source: vbox/trunk/src/libs/openssl-3.1.5/CHANGES.md@ 105770

OpenSSL CHANGES
===============

This is a high-level summary of the most important changes.
For a full list of changes, see the [git commit log][log] and
pick the appropriate release branch.

  [log]: https://github.com/openssl/openssl/commits/

OpenSSL Releases
----------------

 - [OpenSSL 3.1](#openssl-31)
 - [OpenSSL 3.0](#openssl-30)
 - [OpenSSL 1.1.1](#openssl-111)
 - [OpenSSL 1.1.0](#openssl-110)
 - [OpenSSL 1.0.2](#openssl-102)
 - [OpenSSL 1.0.1](#openssl-101)
 - [OpenSSL 1.0.0](#openssl-100)
 - [OpenSSL 0.9.x](#openssl-09x)

OpenSSL 3.1
-----------

### Changes between 3.1.4 and 3.1.5 [30 Jan 2024]

 * A file in PKCS12 format can contain certificates and keys and may come from
   an untrusted source. The PKCS12 specification allows certain fields to be
   NULL, but OpenSSL did not correctly check for this case. A fix has been
   applied to prevent a NULL pointer dereference that results in OpenSSL
   crashing. If an application processes PKCS12 files from an untrusted source
   using the OpenSSL APIs then that application will be vulnerable to this
   issue prior to this fix.

   OpenSSL APIs that were vulnerable to this are: PKCS12_parse(),
   PKCS12_unpack_p7data(), PKCS12_unpack_p7encdata(), PKCS12_unpack_authsafes()
   and PKCS12_newpass().

   We have also fixed a similar issue in SMIME_write_PKCS7(). However since this
   function is related to writing data we do not consider it security
   significant.

   ([CVE-2024-0727])

   *Matt Caswell*

 * When function EVP_PKEY_public_check() is called on RSA public keys,
   a computation is done to confirm that the RSA modulus, n, is composite.
   For valid RSA keys, n is a product of two or more large primes and this
   computation completes quickly. However, if n is an overly large prime,
   then this computation would take a long time.

   An application that calls EVP_PKEY_public_check() and supplies an RSA key
   obtained from an untrusted source could be vulnerable to a Denial of Service
   attack.

   The function EVP_PKEY_public_check() is not called from other OpenSSL
   functions however it is called from the OpenSSL pkey command line
   application. For that reason that application is also vulnerable if used
   with the "-pubin" and "-check" options on untrusted data.

   To resolve this issue RSA keys larger than OPENSSL_RSA_MAX_MODULUS_BITS will
   now fail the check immediately with an RSA_R_MODULUS_TOO_LARGE error reason.

   ([CVE-2023-6237])

   *Tomáš Mráz*

 * Restore the encoding of SM2 PrivateKeyInfo and SubjectPublicKeyInfo to
   have the contained AlgorithmIdentifier.algorithm set to id-ecPublicKey
   rather than SM2.

   *Richard Levitte*

 * The POLY1305 MAC (message authentication code) implementation in OpenSSL
   for PowerPC CPUs saves the contents of vector registers in different
   order than they are restored. Thus the contents of some of these vector
   registers is corrupted when returning to the caller. The vulnerable code is
   used only on newer PowerPC processors supporting the PowerISA 2.07
   instructions.

   The consequences of this kind of internal application state corruption can
   be various - from no consequences, if the calling application does not
   depend on the contents of non-volatile XMM registers at all, to the worst
   consequences, where the attacker could get complete control of the
   application process. However unless the compiler uses the vector registers
   for storing pointers, the most likely consequence, if any, would be an
   incorrect result of some application dependent calculations or a crash
   leading to a denial of service.

   ([CVE-2023-6129])

   *Rohan McLure*

 * Fix excessive time spent in DH check / generation with large Q parameter
   value.

   Applications that use the functions DH_generate_key() to generate an
   X9.42 DH key may experience long delays. Likewise, applications that use
   DH_check_pub_key(), DH_check_pub_key_ex() or EVP_PKEY_public_check()
   to check an X9.42 DH key or X9.42 DH parameters may experience long delays.
   Where the key or parameters that are being checked have been obtained from
   an untrusted source this may lead to a Denial of Service.

   ([CVE-2023-5678])

   *Richard Levitte*

### Changes between 3.1.3 and 3.1.4 [24 Oct 2023]

 * Fix incorrect key and IV resizing issues when calling EVP_EncryptInit_ex2(),
   EVP_DecryptInit_ex2() or EVP_CipherInit_ex2() with OSSL_PARAM parameters
   that alter the key or IV length ([CVE-2023-5363]).

   *Paul Dale*

### Changes between 3.1.2 and 3.1.3 [19 Sep 2023]

 * Fix POLY1305 MAC implementation corrupting XMM registers on Windows.

   The POLY1305 MAC (message authentication code) implementation in OpenSSL
   does not save the contents of non-volatile XMM registers on Windows 64
   platform when calculating the MAC of data larger than 64 bytes. Before
   returning to the caller all the XMM registers are set to zero rather than
   restoring their previous content. The vulnerable code is used only on newer
   x86_64 processors supporting the AVX512-IFMA instructions.

   The consequences of this kind of internal application state corruption can
   be various - from no consequences, if the calling application does not
   depend on the contents of non-volatile XMM registers at all, to the worst
   consequences, where the attacker could get complete control of the
   application process. However given the contents of the registers are just
   zeroized so the attacker cannot put arbitrary values inside, the most likely
   consequence, if any, would be an incorrect result of some application
   dependent calculations or a crash leading to a denial of service.

   ([CVE-2023-4807])

   *Bernd Edlinger*

### Changes between 3.1.1 and 3.1.2 [1 Aug 2023]

 * Fix excessive time spent checking DH q parameter value.

   The function DH_check() performs various checks on DH parameters. After
   fixing CVE-2023-3446 it was discovered that a large q parameter value can
   also trigger an overly long computation during some of these checks.
   A correct q value, if present, cannot be larger than the modulus p
   parameter, thus it is unnecessary to perform these checks if q is larger
   than p.

   If DH_check() is called with such q parameter value,
   DH_CHECK_INVALID_Q_VALUE return flag is set and the computationally
   intensive checks are skipped.

   ([CVE-2023-3817])

   *Tomáš Mráz*

 * Fix DH_check() excessive time with over sized modulus.

   The function DH_check() performs various checks on DH parameters. One of
   those checks confirms that the modulus ("p" parameter) is not too large.
   Trying to use a very large modulus is slow and OpenSSL will not normally use
   a modulus which is over 10,000 bits in length.

   However the DH_check() function checks numerous aspects of the key or
   parameters that have been supplied. Some of those checks use the supplied
   modulus value even if it has already been found to be too large.

   A new limit has been added to DH_check of 32,768 bits. Supplying a
   key/parameters with a modulus over this size will simply cause DH_check() to
   fail.

   ([CVE-2023-3446])

   *Matt Caswell*

 * Do not ignore empty associated data entries with AES-SIV.

   The AES-SIV algorithm allows for authentication of multiple associated
   data entries along with the encryption. To authenticate empty data the
   application has to call `EVP_EncryptUpdate()` (or `EVP_CipherUpdate()`)
   with NULL pointer as the output buffer and 0 as the input buffer length.
   The AES-SIV implementation in OpenSSL just returns success for such call
   instead of performing the associated data authentication operation.
   The empty data thus will not be authenticated. ([CVE-2023-2975])

   Thanks to Juerg Wullschleger (Google) for discovering the issue.

   The fix changes the authentication tag value and the ciphertext for
   applications that use empty associated data entries with AES-SIV.
   To decrypt data encrypted with previous versions of OpenSSL the application
   has to skip calls to `EVP_DecryptUpdate()` for empty associated data
   entries.

   *Tomáš Mráz*

 * When building with the `enable-fips` option and using the resulting
   FIPS provider, TLS 1.2 will, by default, mandate the use of an extended
   master secret (FIPS 140-3 IG G.Q) and the Hash and HMAC DRBGs will
   not operate with truncated digests (FIPS 140-3 IG G.R).

   *Paul Dale*

### Changes between 3.1.0 and 3.1.1 [30 May 2023]

 * Mitigate for the time it takes for `OBJ_obj2txt` to translate gigantic
   OBJECT IDENTIFIER sub-identifiers to canonical numeric text form.

   OBJ_obj2txt() would translate any size OBJECT IDENTIFIER to canonical
   numeric text form.  For gigantic sub-identifiers, this would take a very
   long time, the time complexity being O(n^2) where n is the size of that
   sub-identifier.  ([CVE-2023-2650])

   To mitigitate this, `OBJ_obj2txt()` will only translate an OBJECT
   IDENTIFIER to canonical numeric text form if the size of that OBJECT
   IDENTIFIER is 586 bytes or less, and fail otherwise.

   The basis for this restriction is [RFC 2578 (STD 58), section 3.5]. OBJECT
   IDENTIFIER values, which stipulates that OBJECT IDENTIFIERS may have at
   most 128 sub-identifiers, and that the maximum value that each sub-
   identifier may have is 2^32-1 (4294967295 decimal).

   For each byte of every sub-identifier, only the 7 lower bits are part of
   the value, so the maximum amount of bytes that an OBJECT IDENTIFIER with
   these restrictions may occupy is 32 * 128 / 7, which is approximately 586
   bytes.

   *Richard Levitte*

 * Multiple algorithm implementation fixes for ARM BE platforms.

   *Liu-ErMeng*

 * Added a -pedantic option to fipsinstall that adjusts the various
   settings to ensure strict FIPS compliance rather than backwards
   compatibility.

   *Paul Dale*

 * Fixed buffer overread in AES-XTS decryption on ARM 64 bit platforms which
   happens if the buffer size is 4 mod 5 in 16 byte AES blocks. This can
   trigger a crash of an application using AES-XTS decryption if the memory
   just after the buffer being decrypted is not mapped.
   Thanks to Anton Romanov (Amazon) for discovering the issue.
   ([CVE-2023-1255])

   *Nevine Ebeid*

 * Reworked the Fix for the Timing Oracle in RSA Decryption ([CVE-2022-4304]).
   The previous fix for this timing side channel turned out to cause
   a severe 2-3x performance regression in the typical use case
   compared to 3.0.7. The new fix uses existing constant time
   code paths, and restores the previous performance level while
   fully eliminating all existing timing side channels.
   The fix was developed by Bernd Edlinger with testing support
   by Hubert Kario.

   *Bernd Edlinger*

 * Add FIPS provider configuration option to disallow the use of
   truncated digests with Hash and HMAC DRBGs (q.v. FIPS 140-3 IG D.R.).
   The option '-no_drbg_truncated_digests' can optionally be
   supplied to 'openssl fipsinstall'.

   *Paul Dale*

 * Corrected documentation of X509_VERIFY_PARAM_add0_policy() to mention
   that it does not enable policy checking. Thanks to David Benjamin for
   discovering this issue.
   ([CVE-2023-0466])

   *Tomáš Mráz*

 * Fixed an issue where invalid certificate policies in leaf certificates are
   silently ignored by OpenSSL and other certificate policy checks are skipped
   for that certificate. A malicious CA could use this to deliberately assert
   invalid certificate policies in order to circumvent policy checking on the
   certificate altogether.
   ([CVE-2023-0465])

   *Matt Caswell*

 * Limited the number of nodes created in a policy tree to mitigate
   against CVE-2023-0464.  The default limit is set to 1000 nodes, which
   should be sufficient for most installations.  If required, the limit
   can be adjusted by setting the OPENSSL_POLICY_TREE_NODES_MAX build
   time define to a desired maximum number of nodes or zero to allow
   unlimited growth.
   ([CVE-2023-0464])

   *Paul Dale*

### Changes between 3.0 and 3.1.0 [14 Mar 2023]

 * Add FIPS provider configuration option to enforce the
   Extended Master Secret (EMS) check during the TLS1_PRF KDF.
   The option '-ems-check' can optionally be supplied to
   'openssl fipsinstall'.

   *Shane Lontis*

 * The FIPS provider includes a few non-approved algorithms for
   backward compatibility purposes and the "fips=yes" property query
   must be used for all algorithm fetches to ensure FIPS compliance.

   The algorithms that are included but not approved are Triple DES ECB,
   Triple DES CBC and EdDSA.

   *Paul Dale*

 * Added support for KMAC in KBKDF.

   *Shane Lontis*

 * RNDR and RNDRRS support in provider functions to provide
   random number generation for Arm CPUs (aarch64).

   *Orr Toledano*

 * s_client and s_server apps now explicitly say when the TLS version
   does not include the renegotiation mechanism. This avoids confusion
   between that scenario versus when the TLS version includes secure
   renegotiation but the peer lacks support for it.

   *Felipe Gasper*

 * AES-GCM enabled with AVX512 vAES and vPCLMULQDQ.

   *Tomasz Kantecki, Andrey Matyukov*

 * The various OBJ_* functions have been made thread safe.

   *Paul Dale*

 * Parallel dual-prime 1536/2048-bit modular exponentiation for
   AVX512_IFMA capable processors.

   *Sergey Kirillov, Andrey Matyukov (Intel Corp)*

 * The functions `OPENSSL_LH_stats`, `OPENSSL_LH_node_stats`,
   `OPENSSL_LH_node_usage_stats`, `OPENSSL_LH_stats_bio`,
   `OPENSSL_LH_node_stats_bio` and `OPENSSL_LH_node_usage_stats_bio` are now
   marked deprecated from OpenSSL 3.1 onwards and can be disabled by defining
   `OPENSSL_NO_DEPRECATED_3_1`.

   The macro `DEFINE_LHASH_OF` is now deprecated in favour of the macro
   `DEFINE_LHASH_OF_EX`, which omits the corresponding type-specific function
   definitions for these functions regardless of whether
   `OPENSSL_NO_DEPRECATED_3_1` is defined.

   Users of `DEFINE_LHASH_OF` may start receiving deprecation warnings for these
   functions regardless of whether they are using them. It is recommended that
   users transition to the new macro, `DEFINE_LHASH_OF_EX`.

   *Hugo Landau*

 * When generating safe-prime DH parameters set the recommended private key
   length equivalent to minimum key lengths as in RFC 7919.

   *Tomáš Mráz*

 * Change the default salt length for PKCS#1 RSASSA-PSS signatures to the
   maximum size that is smaller or equal to the digest length to comply with
   FIPS 186-4 section 5. This is implemented by a new option
   `OSSL_PKEY_RSA_PSS_SALT_LEN_AUTO_DIGEST_MAX` ("auto-digestmax") for the
   `rsa_pss_saltlen` parameter, which is now the default. Signature
   verification is not affected by this change and continues to work as before.

   *Clemens Lang*

OpenSSL 3.0
-----------

For OpenSSL 3.0 a [Migration guide][] has been added, so the CHANGES entries
listed here are only a brief description.
The migration guide contains more detailed information related to new features,
breaking changes, and mappings for the large list of deprecated functions.

[Migration guide]: https://github.com/openssl/openssl/tree/master/doc/man7/migration_guide.pod

### Changes between 3.0.7 and 3.0.8 [7 Feb 2023]

 * Fixed NULL dereference during PKCS7 data verification.

   A NULL pointer can be dereferenced when signatures are being
   verified on PKCS7 signed or signedAndEnveloped data. In case the hash
   algorithm used for the signature is known to the OpenSSL library but
   the implementation of the hash algorithm is not available the digest
   initialization will fail. There is a missing check for the return
   value from the initialization function which later leads to invalid
   usage of the digest API most likely leading to a crash.
   ([CVE-2023-0401])

   PKCS7 data is processed by the SMIME library calls and also by the
   time stamp (TS) library calls. The TLS implementation in OpenSSL does
   not call these functions however third party applications would be
   affected if they call these functions to verify signatures on untrusted
   data.

   *Tomáš Mráz*

 * Fixed X.400 address type confusion in X.509 GeneralName.

   There is a type confusion vulnerability relating to X.400 address processing
   inside an X.509 GeneralName. X.400 addresses were parsed as an ASN1_STRING
   but the public structure definition for GENERAL_NAME incorrectly specified
   the type of the x400Address field as ASN1_TYPE. This field is subsequently
   interpreted by the OpenSSL function GENERAL_NAME_cmp as an ASN1_TYPE rather
   than an ASN1_STRING.

   When CRL checking is enabled (i.e. the application sets the
   X509_V_FLAG_CRL_CHECK flag), this vulnerability may allow an attacker to
   pass arbitrary pointers to a memcmp call, enabling them to read memory
   contents or enact a denial of service.
   ([CVE-2023-0286])

   *Hugo Landau*

 * Fixed NULL dereference validating DSA public key.

   An invalid pointer dereference on read can be triggered when an
   application tries to check a malformed DSA public key by the
   EVP_PKEY_public_check() function. This will most likely lead
   to an application crash. This function can be called on public
   keys supplied from untrusted sources which could allow an attacker
   to cause a denial of service attack.

   The TLS implementation in OpenSSL does not call this function
   but applications might call the function if there are additional
   security requirements imposed by standards such as FIPS 140-3.
   ([CVE-2023-0217])

   *Shane Lontis, Tomáš Mráz*

 * Fixed Invalid pointer dereference in d2i_PKCS7 functions.

   An invalid pointer dereference on read can be triggered when an
   application tries to load malformed PKCS7 data with the
   d2i_PKCS7(), d2i_PKCS7_bio() or d2i_PKCS7_fp() functions.

   The result of the dereference is an application crash which could
   lead to a denial of service attack. The TLS implementation in OpenSSL
   does not call this function however third party applications might
   call these functions on untrusted data.
   ([CVE-2023-0216])

   *Tomáš Mráz*

 * Fixed Use-after-free following BIO_new_NDEF.

   The public API function BIO_new_NDEF is a helper function used for
   streaming ASN.1 data via a BIO. It is primarily used internally to OpenSSL
   to support the SMIME, CMS and PKCS7 streaming capabilities, but may also
   be called directly by end user applications.

   The function receives a BIO from the caller, prepends a new BIO_f_asn1
   filter BIO onto the front of it to form a BIO chain, and then returns
   the new head of the BIO chain to the caller. Under certain conditions,
   for example if a CMS recipient public key is invalid, the new filter BIO
   is freed and the function returns a NULL result indicating a failure.
   However, in this case, the BIO chain is not properly cleaned up and the
   BIO passed by the caller still retains internal pointers to the previously
   freed filter BIO. If the caller then goes on to call BIO_pop() on the BIO
   then a use-after-free will occur. This will most likely result in a crash.
   ([CVE-2023-0215])

   *Viktor Dukhovni, Matt Caswell*

 * Fixed Double free after calling PEM_read_bio_ex.

   The function PEM_read_bio_ex() reads a PEM file from a BIO and parses and
   decodes the "name" (e.g. "CERTIFICATE"), any header data and the payload
   data. If the function succeeds then the "name_out", "header" and "data"
   arguments are populated with pointers to buffers containing the relevant
   decoded data. The caller is responsible for freeing those buffers. It is
   possible to construct a PEM file that results in 0 bytes of payload data.
   In this case PEM_read_bio_ex() will return a failure code but will populate
   the header argument with a pointer to a buffer that has already been freed.
   If the caller also frees this buffer then a double free will occur. This
   will most likely lead to a crash.

   The functions PEM_read_bio() and PEM_read() are simple wrappers around
   PEM_read_bio_ex() and therefore these functions are also directly affected.

   These functions are also called indirectly by a number of other OpenSSL
   functions including PEM_X509_INFO_read_bio_ex() and
   SSL_CTX_use_serverinfo_file() which are also vulnerable. Some OpenSSL
   internal uses of these functions are not vulnerable because the caller does
   not free the header argument if PEM_read_bio_ex() returns a failure code.
   ([CVE-2022-4450])

   *Kurt Roeckx, Matt Caswell*

 * Fixed Timing Oracle in RSA Decryption.

   A timing based side channel exists in the OpenSSL RSA Decryption
   implementation which could be sufficient to recover a plaintext across
   a network in a Bleichenbacher style attack. To achieve a successful
   decryption an attacker would have to be able to send a very large number
   of trial messages for decryption. The vulnerability affects all RSA padding
   modes: PKCS#1 v1.5, RSA-OEAP and RSASVE.
   ([CVE-2022-4304])

   *Dmitry Belyavsky, Hubert Kario*

 * Fixed X.509 Name Constraints Read Buffer Overflow.

   A read buffer overrun can be triggered in X.509 certificate verification,
   specifically in name constraint checking. The read buffer overrun might
   result in a crash which could lead to a denial of service attack.
   In a TLS client, this can be triggered by connecting to a malicious
   server. In a TLS server, this can be triggered if the server requests
   client authentication and a malicious client connects.
   ([CVE-2022-4203])

   *Viktor Dukhovni*

 * Fixed X.509 Policy Constraints Double Locking security issue.

   If an X.509 certificate contains a malformed policy constraint and
   policy processing is enabled, then a write lock will be taken twice
   recursively.  On some operating systems (most widely: Windows) this
   results in a denial of service when the affected process hangs.  Policy
   processing being enabled on a publicly facing server is not considered
   to be a common setup.
   ([CVE-2022-3996])

   *Paul Dale*

 * Our provider implementations of `OSSL_FUNC_KEYMGMT_EXPORT` and
   `OSSL_FUNC_KEYMGMT_GET_PARAMS` for EC and SM2 keys now honor
   `OSSL_PKEY_PARAM_EC_POINT_CONVERSION_FORMAT` as set (and
   default to `POINT_CONVERSION_UNCOMPRESSED`) when exporting
   `OSSL_PKEY_PARAM_PUB_KEY`, instead of unconditionally using
   `POINT_CONVERSION_COMPRESSED` as in previous 3.x releases.
   For symmetry, our implementation of `EVP_PKEY_ASN1_METHOD->export_to`
   for legacy EC and SM2 keys is also changed similarly to honor the
   equivalent conversion format flag as specified in the underlying
   `EC_KEY` object being exported to a provider, when this function is
   called through `EVP_PKEY_export()`.

   *Nicola Tuveri*

 * Fixed a type confusion vulnerability relating to X.400 address processing
   inside an X.509 GeneralName. X.400 addresses were parsed as an `ASN1_STRING`
   but subsequently interpreted by `GENERAL_NAME_cmp` as an `ASN1_TYPE`. This
   vulnerability may allow an attacker who can provide a certificate chain and
   CRL (neither of which need have a valid signature) to pass arbitrary pointers
   to a `memcmp` call, creating a possible read primitive, subject to some
   constraints. Refer to the advisory for more information. Thanks to David
   Benjamin for discovering this issue. ([CVE-2023-0286])

   This issue has been fixed by changing the public header file definition of
   `GENERAL_NAME` so that `x400Address` reflects the implementation. It was not
   possible for any existing application to successfully use the existing
   definition; however, if any application references the `x400Address` field
   (e.g. in dead code), note that the type of this field has changed. There is
   no ABI change.

   *Hugo Landau*

### Changes between 3.0.6 and 3.0.7 [1 Nov 2022]

 * Fixed two buffer overflows in punycode decoding functions.

   A buffer overrun can be triggered in X.509 certificate verification,
   specifically in name constraint checking. Note that this occurs after
   certificate chain signature verification and requires either a CA to
   have signed the malicious certificate or for the application to continue
   certificate verification despite failure to construct a path to a trusted
   issuer.

   In a TLS client, this can be triggered by connecting to a malicious
   server.  In a TLS server, this can be triggered if the server requests
   client authentication and a malicious client connects.

   An attacker can craft a malicious email address to overflow
   an arbitrary number of bytes containing the `.`  character (decimal 46)
   on the stack.  This buffer overflow could result in a crash (causing a
   denial of service).
   ([CVE-2022-3786])

   An attacker can craft a malicious email address to overflow four
   attacker-controlled bytes on the stack.  This buffer overflow could
   result in a crash (causing a denial of service) or potentially remote code
   execution depending on stack layout for any given platform/compiler.
   ([CVE-2022-3602])

   *Paul Dale*

 * Removed all references to invalid OSSL_PKEY_PARAM_RSA names for CRT
   parameters in OpenSSL code.
   Applications should not use the names OSSL_PKEY_PARAM_RSA_FACTOR,
   OSSL_PKEY_PARAM_RSA_EXPONENT and OSSL_PKEY_PARAM_RSA_COEFFICIENT.
   Use the numbered names such as OSSL_PKEY_PARAM_RSA_FACTOR1 instead.
   Using these invalid names may cause algorithms to use slower methods
   that ignore the CRT parameters.

   *Shane Lontis*

 * Fixed a regression introduced in 3.0.6 version raising errors on some stack
   operations.

   *Tomáš Mráz*

 * Fixed a regression introduced in 3.0.6 version not refreshing the certificate
   data to be signed before signing the certificate.

   *Gibeom Gwon*

 * Added RIPEMD160 to the default provider.

   *Paul Dale*

 * Ensured that the key share group sent or accepted for the key exchange
   is allowed for the protocol version.

   *Matt Caswell*

### Changes between 3.0.5 and 3.0.6 [11 Oct 2022]

 * OpenSSL supports creating a custom cipher via the legacy
   EVP_CIPHER_meth_new() function and associated function calls. This function
   was deprecated in OpenSSL 3.0 and application authors are instead encouraged
   to use the new provider mechanism in order to implement custom ciphers.

   OpenSSL versions 3.0.0 to 3.0.5 incorrectly handle legacy custom ciphers
   passed to the EVP_EncryptInit_ex2(), EVP_DecryptInit_ex2() and
   EVP_CipherInit_ex2() functions (as well as other similarly named encryption
   and decryption initialisation functions). Instead of using the custom cipher
   directly it incorrectly tries to fetch an equivalent cipher from the
   available providers. An equivalent cipher is found based on the NID passed to
   EVP_CIPHER_meth_new(). This NID is supposed to represent the unique NID for a
   given cipher. However it is possible for an application to incorrectly pass
   NID_undef as this value in the call to EVP_CIPHER_meth_new(). When NID_undef
   is used in this way the OpenSSL encryption/decryption initialisation function
   will match the NULL cipher as being equivalent and will fetch this from the
   available providers. This will succeed if the default provider has been
   loaded (or if a third party provider has been loaded that offers this
   cipher). Using the NULL cipher means that the plaintext is emitted as the
   ciphertext.

   Applications are only affected by this issue if they call
   EVP_CIPHER_meth_new() using NID_undef and subsequently use it in a call to an
   encryption/decryption initialisation function. Applications that only use
   SSL/TLS are not impacted by this issue.
   ([CVE-2022-3358])

   *Matt Caswell*

 * Fix LLVM vs Apple LLVM version numbering confusion that caused build failures
   on MacOS 10.11

   *Richard Levitte*

 * Fixed the linux-mips64 Configure target which was missing the
   SIXTY_FOUR_BIT bn_ops flag. This was causing heap corruption on that
   platform.

   *Adam Joseph*

 * Fix handling of a ticket key callback that returns 0 in TLSv1.3 to not send a
   ticket

   *Matt Caswell*

 * Correctly handle a retransmitted ClientHello in DTLS

   *Matt Caswell*

 * Fixed detection of ktls support in cross-compile environment on Linux

   *Tomas Mraz*

 * Fixed some regressions and test failures when running the 3.0.0 FIPS provider
   against 3.0.x

   *Paul Dale*

 * Fixed SSL_pending() and SSL_has_pending() with DTLS which were failing to
   report correct results in some cases

   *Matt Caswell*

 * Fix UWP builds by defining VirtualLock

   *Charles Milette*

 * For known safe primes use the minimum key length according to RFC 7919.
   Longer private key sizes unnecessarily raise the cycles needed to compute the
   shared secret without any increase of the real security. This fixes a
   regression from 1.1.1 where these shorter keys were generated for the known
   safe primes.

   *Tomas Mraz*

 * Added the loongarch64 target

   *Shi Pujin*

 * Fixed EC ASM flag passing. Flags for ASM implementations of EC curves were
   only passed to the FIPS provider and not to the default or legacy provider.

   *Juergen Christ*

 * Fixed reported performance degradation on aarch64. Restored the
   implementation prior to commit 2621751 ("aes/asm/aesv8-armx.pl: avoid
   32-bit lane assignment in CTR mode") for 64bit targets only, since it is
   reportedly 2-17% slower and the silicon errata only affects 32bit targets.
   The new algorithm is still used for 32 bit targets.

   *Bernd Edlinger*

 * Added a missing header for memcmp that caused compilation failure on some
   platforms

   *Gregor Jasny*

### Changes between 3.0.4 and 3.0.5 [5 Jul 2022]

 * The OpenSSL 3.0.4 release introduced a serious bug in the RSA
   implementation for X86_64 CPUs supporting the AVX512IFMA instructions.
   This issue makes the RSA implementation with 2048 bit private keys
   incorrect on such machines and memory corruption will happen during
   the computation. As a consequence of the memory corruption an attacker
   may be able to trigger a remote code execution on the machine performing
   the computation.

   SSL/TLS servers or other servers using 2048 bit RSA private keys running
   on machines supporting AVX512IFMA instructions of the X86_64 architecture
   are affected by this issue.
   ([CVE-2022-2274])

   *Xi Ruoyao*

 * AES OCB mode for 32-bit x86 platforms using the AES-NI assembly optimised
   implementation would not encrypt the entirety of the data under some
   circumstances.  This could reveal sixteen bytes of data that was
   preexisting in the memory that wasn't written.  In the special case of
   "in place" encryption, sixteen bytes of the plaintext would be revealed.

   Since OpenSSL does not support OCB based cipher suites for TLS and DTLS,
   they are both unaffected.
   ([CVE-2022-2097])

   *Alex Chernyakhovsky, David Benjamin, Alejandro Sedeño*

### Changes between 3.0.3 and 3.0.4 [21 Jun 2022]

 * In addition to the c_rehash shell command injection identified in
   CVE-2022-1292, further bugs where the c_rehash script does not
   properly sanitise shell metacharacters to prevent command injection have been
   fixed.

   When the CVE-2022-1292 was fixed it was not discovered that there
   are other places in the script where the file names of certificates
   being hashed were possibly passed to a command executed through the shell.

   This script is distributed by some operating systems in a manner where
   it is automatically executed.  On such operating systems, an attacker
   could execute arbitrary commands with the privileges of the script.

   Use of the c_rehash script is considered obsolete and should be replaced
   by the OpenSSL rehash command line tool.
   (CVE-2022-2068)

   *Daniel Fiala, Tomáš Mráz*

 * Case insensitive string comparison no longer uses locales.  It has instead
   been directly implemented.

   *Paul Dale*

### Changes between 3.0.2 and 3.0.3 [3 May 2022]

 * Case insensitive string comparison is reimplemented via new locale-agnostic
   comparison functions OPENSSL_str[n]casecmp always using the POSIX locale for
   comparison. The previous implementation had problems when the Turkish locale
   was used.

   *Dmitry Belyavskiy*

 * Fixed a bug in the c_rehash script which was not properly sanitising shell
   metacharacters to prevent command injection.  This script is distributed by
   some operating systems in a manner where it is automatically executed.  On
   such operating systems, an attacker could execute arbitrary commands with the
   privileges of the script.

   Use of the c_rehash script is considered obsolete and should be replaced
   by the OpenSSL rehash command line tool.
   (CVE-2022-1292)

   *Tomáš Mráz*

 * Fixed a bug in the function `OCSP_basic_verify` that verifies the signer
   certificate on an OCSP response. The bug caused the function in the case
   where the (non-default) flag OCSP_NOCHECKS is used to return a postivie
   response (meaning a successful verification) even in the case where the
   response signing certificate fails to verify.

   It is anticipated that most users of `OCSP_basic_verify` will not use the
   OCSP_NOCHECKS flag. In this case the `OCSP_basic_verify` function will return
   a negative value (indicating a fatal error) in the case of a certificate
   verification failure. The normal expected return value in this case would be
   0.

   This issue also impacts the command line OpenSSL "ocsp" application. When
   verifying an ocsp response with the "-no_cert_checks" option the command line
   application will report that the verification is successful even though it
   has in fact failed. In this case the incorrect successful response will also
   be accompanied by error messages showing the failure and contradicting the
   apparently successful result.
   ([CVE-2022-1343])

   *Matt Caswell*

 * Fixed a bug where the RC4-MD5 ciphersuite incorrectly used the
   AAD data as the MAC key. This made the MAC key trivially predictable.

   An attacker could exploit this issue by performing a man-in-the-middle attack
   to modify data being sent from one endpoint to an OpenSSL 3.0 recipient such
   that the modified data would still pass the MAC integrity check.

   Note that data sent from an OpenSSL 3.0 endpoint to a non-OpenSSL 3.0
   endpoint will always be rejected by the recipient and the connection will
   fail at that point. Many application protocols require data to be sent from
   the client to the server first. Therefore, in such a case, only an OpenSSL
   3.0 server would be impacted when talking to a non-OpenSSL 3.0 client.

   If both endpoints are OpenSSL 3.0 then the attacker could modify data being
   sent in both directions. In this case both clients and servers could be
   affected, regardless of the application protocol.

   Note that in the absence of an attacker this bug means that an OpenSSL 3.0
   endpoint communicating with a non-OpenSSL 3.0 endpoint will fail to complete
   the handshake when using this ciphersuite.

   The confidentiality of data is not impacted by this issue, i.e. an attacker
   cannot decrypt data that has been encrypted using this ciphersuite - they can
   only modify it.

   In order for this attack to work both endpoints must legitimately negotiate
   the RC4-MD5 ciphersuite. This ciphersuite is not compiled by default in
   OpenSSL 3.0, and is not available within the default provider or the default
   ciphersuite list. This ciphersuite will never be used if TLSv1.3 has been
   negotiated. In order for an OpenSSL 3.0 endpoint to use this ciphersuite the
   following must have occurred:

   1) OpenSSL must have been compiled with the (non-default) compile time option
      enable-weak-ssl-ciphers

   2) OpenSSL must have had the legacy provider explicitly loaded (either
      through application code or via configuration)

   3) The ciphersuite must have been explicitly added to the ciphersuite list

   4) The libssl security level must have been set to 0 (default is 1)

   5) A version of SSL/TLS below TLSv1.3 must have been negotiated

   6) Both endpoints must negotiate the RC4-MD5 ciphersuite in preference to any
      others that both endpoints have in common
   (CVE-2022-1434)

   *Matt Caswell*

 * Fix a bug in the OPENSSL_LH_flush() function that breaks reuse of the memory
   occupied by the removed hash table entries.

   This function is used when decoding certificates or keys. If a long lived
   process periodically decodes certificates or keys its memory usage will
   expand without bounds and the process might be terminated by the operating
   system causing a denial of service. Also traversing the empty hash table
   entries will take increasingly more time.

   Typically such long lived processes might be TLS clients or TLS servers
   configured to accept client certificate authentication.
   (CVE-2022-1473)

   *Hugo Landau, Aliaksei Levin*

 * The functions `OPENSSL_LH_stats` and `OPENSSL_LH_stats_bio` now only report
   the `num_items`, `num_nodes` and `num_alloc_nodes` statistics. All other
   statistics are no longer supported. For compatibility, these statistics are
   still listed in the output but are now always reported as zero.

   *Hugo Landau*

### Changes between 3.0.1 and 3.0.2 [15 Mar 2022]

 * Fixed a bug in the BN_mod_sqrt() function that can cause it to loop forever
   for non-prime moduli.

   Internally this function is used when parsing certificates that contain
   elliptic curve public keys in compressed form or explicit elliptic curve
   parameters with a base point encoded in compressed form.

   It is possible to trigger the infinite loop by crafting a certificate that
   has invalid explicit curve parameters.

   Since certificate parsing happens prior to verification of the certificate
   signature, any process that parses an externally supplied certificate may thus
   be subject to a denial of service attack. The infinite loop can also be
   reached when parsing crafted private keys as they can contain explicit
   elliptic curve parameters.

   Thus vulnerable situations include:

    - TLS clients consuming server certificates
    - TLS servers consuming client certificates
    - Hosting providers taking certificates or private keys from customers
    - Certificate authorities parsing certification requests from subscribers
    - Anything else which parses ASN.1 elliptic curve parameters

   Also any other applications that use the BN_mod_sqrt() where the attacker
   can control the parameter values are vulnerable to this DoS issue.
   ([CVE-2022-0778])

   *Tomáš Mráz*

 * Add ciphersuites based on DHE_PSK (RFC 4279) and ECDHE_PSK (RFC 5489)
   to the list of ciphersuites providing Perfect Forward Secrecy as
   required by SECLEVEL >= 3.

   *Dmitry Belyavskiy, Nicola Tuveri*

 * Made the AES constant time code for no-asm configurations
   optional due to the resulting 95% performance degradation.
   The AES constant time code can be enabled, for no assembly
   builds, with: ./config no-asm -DOPENSSL_AES_CONST_TIME

   *Paul Dale*

 * Fixed PEM_write_bio_PKCS8PrivateKey() to make it possible to use empty
   passphrase strings.

   *Darshan Sen*

 * The negative return value handling of the certificate verification callback
   was reverted. The replacement is to set the verification retry state with
   the SSL_set_retry_verify() function.

   *Tomáš Mráz*

### Changes between 3.0.0 and 3.0.1 [14 Dec 2021]

 * Fixed invalid handling of X509_verify_cert() internal errors in libssl
   Internally libssl in OpenSSL calls X509_verify_cert() on the client side to
   verify a certificate supplied by a server. That function may return a
   negative return value to indicate an internal error (for example out of
   memory). Such a negative return value is mishandled by OpenSSL and will cause
   an IO function (such as SSL_connect() or SSL_do_handshake()) to not indicate
   success and a subsequent call to SSL_get_error() to return the value
   SSL_ERROR_WANT_RETRY_VERIFY. This return value is only supposed to be
   returned by OpenSSL if the application has previously called
   SSL_CTX_set_cert_verify_callback(). Since most applications do not do this
   the SSL_ERROR_WANT_RETRY_VERIFY return value from SSL_get_error() will be
   totally unexpected and applications may not behave correctly as a result. The
   exact behaviour will depend on the application but it could result in
   crashes, infinite loops or other similar incorrect responses.

   This issue is made more serious in combination with a separate bug in OpenSSL
   3.0 that will cause X509_verify_cert() to indicate an internal error when
   processing a certificate chain. This will occur where a certificate does not
   include the Subject Alternative Name extension but where a Certificate
   Authority has enforced name constraints. This issue can occur even with valid
   chains.
   ([CVE-2021-4044])

   *Matt Caswell*

 * Corrected a few file name and file reference bugs in the build,
   installation and setup scripts, which lead to installation verification
   failures.  Slightly enhanced the installation verification script.

   *Richard Levitte*

 * Fixed EVP_PKEY_eq() to make it possible to use it with strictly private
   keys.

   *Richard Levitte*

 * Fixed PVK encoder to properly query for the passphrase.

   *Tomáš Mráz*

 * Multiple fixes in the OSSL_HTTP API functions.

   *David von Oheimb*

 * Allow sign extension in OSSL_PARAM_allocate_from_text() for the
   OSSL_PARAM_INTEGER data type and return error on negative numbers
   used with the OSSL_PARAM_UNSIGNED_INTEGER data type. Make
   OSSL_PARAM_BLD_push_BN{,_pad}() return an error on negative numbers.

   *Richard Levitte*

 * Allow copying uninitialized digest contexts with EVP_MD_CTX_copy_ex.

   *Tomáš Mráz*

 * Fixed detection of ARMv7 and ARM64 CPU features on FreeBSD.

   *Allan Jude*

 * Multiple threading fixes.

   *Matt Caswell*

 * Added NULL digest implementation to keep compatibility with 1.1.1 version.

   *Tomáš Mráz*

 * Allow fetching an operation from the provider that owns an unexportable key
   as a fallback if that is still allowed by the property query.

   *Richard Levitte*

### Changes between 1.1.1 and 3.0.0 [7 sep 2021]

 * TLS_MAX_VERSION, DTLS_MAX_VERSION and DTLS_MIN_VERSION constants are now
   deprecated.

   *Matt Caswell*

 * The `OPENSSL_s390xcap` environment variable can be used to set bits in the
   S390X capability vector to zero. This simplifies testing of different code
   paths on S390X architecture.

   *Patrick Steuer*

 * Encrypting more than 2^64 TLS records with AES-GCM is disallowed
   as per FIPS 140-2 IG A.5 "Key/IV Pair Uniqueness Requirements from
   SP 800-38D". The communication will fail at this point.

   *Paul Dale*

 * The EC_GROUP_clear_free() function is deprecated as there is nothing
   confidential in EC_GROUP data.

   *Nicola Tuveri*

 * The byte order mark (BOM) character is ignored if encountered at the
   beginning of a PEM-formatted file.

   *Dmitry Belyavskiy*

 * Added CMS support for the Russian GOST algorithms.

   *Dmitry Belyavskiy*

 * Due to move of the implementation of cryptographic operations
   to the providers, validation of various operation parameters can
   be postponed until the actual operation is executed where previously
   it happened immediately when an operation parameter was set.

   For example when setting an unsupported curve with
   EVP_PKEY_CTX_set_ec_paramgen_curve_nid() this function call will not
   fail but later keygen operations with the EVP_PKEY_CTX will fail.

   *OpenSSL team members and many third party contributors*

 * The EVP_get_cipherbyname() function will return NULL for algorithms such as
   "AES-128-SIV", "AES-128-CBC-CTS" and "CAMELLIA-128-CBC-CTS" which were
   previously only accessible via low-level interfaces. Use EVP_CIPHER_fetch()
   instead to retrieve these algorithms from a provider.

   *Shane Lontis*

 * On build targets where the multilib postfix is set in the build
   configuration the libdir directory was changing based on whether
   the lib directory with the multilib postfix exists on the system
   or not. This unpredictable behavior was removed and eventual
   multilib postfix is now always added to the default libdir. Use
   `--libdir=lib` to override the libdir if adding the postfix is
   undesirable.

   *Jan Lána*

 * The triple DES key wrap functionality now conforms to RFC 3217 but is
   no longer interoperable with OpenSSL 1.1.1.

   *Paul Dale*

 * The ERR_GET_FUNC() function was removed.  With the loss of meaningful
   function codes, this function can only cause problems for calling
   applications.

   *Paul Dale*

 * Add a configurable flag to output date formats as ISO 8601. Does not
   change the default date format.

   *William Edmisten*

 * Version of MSVC earlier than 1300 could get link warnings, which could
   be suppressed if the undocumented -DI_CAN_LIVE_WITH_LNK4049 was set.
   Support for this flag has been removed.

   *Rich Salz*

 * Rework and make DEBUG macros consistent. Remove unused -DCONF_DEBUG,
   -DBN_CTX_DEBUG, and REF_PRINT. Add a new tracing category and use it for
   printing reference counts. Rename -DDEBUG_UNUSED to -DUNUSED_RESULT_DEBUG
   Fix BN_DEBUG_RAND so it compiles and, when set, force DEBUG_RAND to be set
   also. Rename engine_debug_ref to be ENGINE_REF_PRINT also for consistency.

   *Rich Salz*

 * The signatures of the functions to get and set options on SSL and
   SSL_CTX objects changed from "unsigned long" to "uint64_t" type.
   Some source code changes may be required.

   *Rich Salz*

 * The public definitions of conf_method_st and conf_st have been
   deprecated. They will be made opaque in a future release.

   *Rich Salz and Tomáš Mráz*

 * Client-initiated renegotiation is disabled by default. To allow it, use
   the -client_renegotiation option, the SSL_OP_ALLOW_CLIENT_RENEGOTIATION
   flag, or the "ClientRenegotiation" config parameter as appropriate.

   *Rich Salz*

 * Add "abspath" and "includedir" pragma's to config files, to prevent,
   or modify relative pathname inclusion.

   *Rich Salz*

 * OpenSSL includes a cryptographic module that is intended to be FIPS 140-2
   validated. Please consult the README-FIPS and
   README-PROVIDERS files, as well as the migration guide.

   *OpenSSL team members and many third party contributors*

 * For the key types DH and DHX the allowed settable parameters are now different.

   *Shane Lontis*

 * The openssl commands that read keys, certificates, and CRLs now
   automatically detect the PEM or DER format of the input files.

   *David von Oheimb, Richard Levitte, and Tomáš Mráz*

 * Added enhanced PKCS#12 APIs which accept a library context.

   *Jon Spillett*

 * The default manual page suffix ($MANSUFFIX) has been changed to "ossl"

   *Matt Caswell*

 * Added support for Kernel TLS (KTLS).

   *Boris Pismenny, John Baldwin and Andrew Gallatin*

 * Support for RFC 5746 secure renegotiation is now required by default for
   SSL or TLS connections to succeed.

   *Benjamin Kaduk*

 * The signature of the `copy` functional parameter of the
   EVP_PKEY_meth_set_copy() function has changed so its `src` argument is
   now `const EVP_PKEY_CTX *` instead of `EVP_PKEY_CTX *`. Similarly
   the signature of the `pub_decode` functional parameter of the
   EVP_PKEY_asn1_set_public() function has changed so its `pub` argument is
   now `const X509_PUBKEY *` instead of `X509_PUBKEY *`.

   *David von Oheimb*

 * The error return values from some control calls (ctrl) have changed.

   *Paul Dale*

 * A public key check is now performed during EVP_PKEY_derive_set_peer().

   *Shane Lontis*

 * Many functions in the EVP_ namespace that are getters of values from
   implementations or contexts were renamed to include get or get0 in their
   names. Old names are provided as macro aliases for compatibility and
   are not deprecated.

   *Tomáš Mráz*

 * The EVP_PKEY_CTRL_PKCS7_ENCRYPT, EVP_PKEY_CTRL_PKCS7_DECRYPT,
   EVP_PKEY_CTRL_PKCS7_SIGN, EVP_PKEY_CTRL_CMS_ENCRYPT,
   EVP_PKEY_CTRL_CMS_DECRYPT, and EVP_PKEY_CTRL_CMS_SIGN control operations
   are deprecated.

   *Tomáš Mráz*

 * The EVP_PKEY_public_check() and EVP_PKEY_param_check() functions now work for
   more key types.

 * The output from the command line applications may have minor
   changes.

   *Paul Dale*

 * The output from numerous "printing" may have minor changes.

   *David von Oheimb*

 * Windows thread synchronization uses read/write primitives (SRWLock) when
   supported by the OS, otherwise CriticalSection continues to be used.

   *Vincent Drake*

 * Add filter BIO BIO_f_readbuffer() that allows BIO_tell() and BIO_seek() to
   work on read only BIO source/sinks that do not support these functions.
   This allows piping or redirection of a file BIO using stdin to be buffered
   into memory. This is used internally in OSSL_DECODER_from_bio().

   *Shane Lontis*

 * OSSL_STORE_INFO_get_type() may now return an additional value. In 1.1.1
   this function would return one of the values OSSL_STORE_INFO_NAME,
   OSSL_STORE_INFO_PKEY, OSSL_STORE_INFO_PARAMS, OSSL_STORE_INFO_CERT or
   OSSL_STORE_INFO_CRL. Decoded public keys would previously have been reported
   as type OSSL_STORE_INFO_PKEY in 1.1.1. In 3.0 decoded public keys are now
   reported as having the new type OSSL_STORE_INFO_PUBKEY. Applications
   using this function should be amended to handle the changed return value.

   *Richard Levitte*

 * Improved adherence to Enhanced Security Services (ESS, RFC 2634 and RFC 5035)
   for the TSP and CMS Advanced Electronic Signatures (CAdES) implementations.
   As required by RFC 5035 check both ESSCertID and ESSCertIDv2 if both present.
   Correct the semantics of checking the validation chain in case ESSCertID{,v2}
   contains more than one certificate identifier: This means that all
   certificates referenced there MUST be part of the validation chain.

   *David von Oheimb*

 * The implementation of older EVP ciphers related to CAST, IDEA, SEED, RC2, RC4,
   RC5, DESX and DES have been moved to the legacy provider.

   *Matt Caswell*

 * The implementation of the EVP digests MD2, MD4, MDC2, WHIRLPOOL and
   RIPEMD-160 have been moved to the legacy provider.

   *Matt Caswell*

 * The deprecated function EVP_PKEY_get0() now returns NULL being called for a
   provided key.

   *Dmitry Belyavskiy*

 * The deprecated functions EVP_PKEY_get0_RSA(),
   EVP_PKEY_get0_DSA(), EVP_PKEY_get0_EC_KEY(), EVP_PKEY_get0_DH(),
   EVP_PKEY_get0_hmac(), EVP_PKEY_get0_poly1305() and EVP_PKEY_get0_siphash() as
   well as the similarly named "get1" functions behave differently in
   OpenSSL 3.0.

   *Matt Caswell*

 * A number of functions handling low-level keys or engines were deprecated
   including EVP_PKEY_set1_engine(), EVP_PKEY_get0_engine(), EVP_PKEY_assign(),
   EVP_PKEY_get0(), EVP_PKEY_get0_hmac(), EVP_PKEY_get0_poly1305() and
   EVP_PKEY_get0_siphash().

   *Matt Caswell*

 * PKCS#5 PBKDF1 key derivation has been moved from PKCS5_PBE_keyivgen() into
   the legacy crypto provider as an EVP_KDF. Applications requiring this KDF
   will need to load the legacy crypto provider. This includes these PBE
   algorithms which use this KDF:
   - NID_pbeWithMD2AndDES_CBC
   - NID_pbeWithMD5AndDES_CBC
   - NID_pbeWithSHA1AndRC2_CBC
   - NID_pbeWithMD2AndRC2_CBC
   - NID_pbeWithMD5AndRC2_CBC
   - NID_pbeWithSHA1AndDES_CBC

   *Jon Spillett*

 * Deprecated obsolete BIO_set_callback(), BIO_get_callback(), and
   BIO_debug_callback() functions.

   *Tomáš Mráz*

 * Deprecated obsolete EVP_PKEY_CTX_get0_dh_kdf_ukm() and
   EVP_PKEY_CTX_get0_ecdh_kdf_ukm() functions.

   *Tomáš Mráz*

 * The RAND_METHOD APIs have been deprecated.

   *Paul Dale*

 * The SRP APIs have been deprecated.

   *Matt Caswell*

 * Add a compile time option to prevent the caching of provider fetched
   algorithms.  This is enabled by including the no-cached-fetch option
   at configuration time.

   *Paul Dale*

 * pkcs12 now uses defaults of PBKDF2, AES and SHA-256, with a MAC iteration
   count of PKCS12_DEFAULT_ITER.

   *Tomáš Mráz and Sahana Prasad*

 * The openssl speed command does not use low-level API calls anymore.

   *Tomáš Mráz*

 * Parallel dual-prime 1024-bit modular exponentiation for AVX512_IFMA
   capable processors.

   *Ilya Albrekht, Sergey Kirillov, Andrey Matyukov (Intel Corp)*

 * Combining the Configure options no-ec and no-dh no longer disables TLSv1.3.

   *Matt Caswell*

 * Implemented support for fully "pluggable" TLSv1.3 groups. This means that
   providers may supply their own group implementations (using either the "key
   exchange" or the "key encapsulation" methods) which will automatically be
   detected and used by libssl.

   *Matt Caswell, Nicola Tuveri*

 * The undocumented function X509_certificate_type() has been deprecated;

   *Rich Salz*

 * Deprecated the obsolete BN_pseudo_rand() and BN_pseudo_rand_range().

   *Tomáš Mráz*

 * Removed RSA padding mode for SSLv23 (which was only used for
   SSLv2). This includes the functions RSA_padding_check_SSLv23() and
   RSA_padding_add_SSLv23() and the `-ssl` option in the deprecated
   `rsautl` command.

   *Rich Salz*

 * Deprecated the obsolete X9.31 RSA key generation related functions.

 * While a callback function set via `SSL_CTX_set_cert_verify_callback()`
   is not allowed to return a value > 1, this is no more taken as failure.

   *Viktor Dukhovni and David von Oheimb*

 * Deprecated the obsolete X9.31 RSA key generation related functions
   BN_X931_generate_Xpq(), BN_X931_derive_prime_ex(), and
   BN_X931_generate_prime_ex().

   *Tomáš Mráz*

 * The default key generation method for the regular 2-prime RSA keys was
   changed to the FIPS 186-4 B.3.6 method.

   *Shane Lontis*

 * Deprecated the BN_is_prime_ex() and BN_is_prime_fasttest_ex() functions.

   *Kurt Roeckx*

 * Deprecated EVP_MD_CTX_set_update_fn() and EVP_MD_CTX_update_fn().

   *Rich Salz*

 * Deprecated the type OCSP_REQ_CTX and the functions OCSP_REQ_CTX_*() and
   replaced with OSSL_HTTP_REQ_CTX and the functions OSSL_HTTP_REQ_CTX_*().

   *Rich Salz, Richard Levitte, and David von Oheimb*

 * Deprecated `X509_http_nbio()` and `X509_CRL_http_nbio()`.

   *David von Oheimb*

 * Deprecated `OCSP_parse_url()`.

   *David von Oheimb*

 * Validation of SM2 keys has been separated from the validation of regular EC
   keys.

   *Nicola Tuveri*

 * Behavior of the `pkey` app is changed, when using the `-check` or `-pubcheck`
   switches: a validation failure triggers an early exit, returning a failure
   exit status to the parent process.

   *Nicola Tuveri*

 * Changed behavior of SSL_CTX_set_ciphersuites() and SSL_set_ciphersuites()
   to ignore unknown ciphers.

   *Otto Hollmann*

 * The `-cipher-commands` and `-digest-commands` options
   of the command line utility `list` have been deprecated.
   Instead use the `-cipher-algorithms` and `-digest-algorithms` options.

   *Dmitry Belyavskiy*

 * Added convenience functions for generating asymmetric key pairs:
   The 'quick' one-shot (yet somewhat limited) function L<EVP_PKEY_Q_keygen(3)>
   and macros for the most common cases: <EVP_RSA_gen(3)> and L<EVP_EC_gen(3)>.

   *David von Oheimb*

 * All of the low-level EC_KEY functions have been deprecated.

   *Shane Lontis, Paul Dale, Richard Levitte, and Tomáš Mráz*

 * Deprecated all the libcrypto and libssl error string loading
   functions.

   *Richard Levitte*

 * The functions SSL_CTX_set_tmp_dh_callback and SSL_set_tmp_dh_callback, as
   well as the macros SSL_CTX_set_tmp_dh() and SSL_set_tmp_dh() have been
   deprecated.

   *Matt Caswell*

 * The `-crypt` option to the `passwd` command line tool has been removed.

   *Paul Dale*

 * The -C option to the `x509`, `dhparam`, `dsaparam`, and `ecparam` commands
   were removed.

   *Rich Salz*

 * Add support for AES Key Wrap inverse ciphers to the EVP layer.

   *Shane Lontis*

 * Deprecated EVP_PKEY_set1_tls_encodedpoint() and
   EVP_PKEY_get1_tls_encodedpoint().

   *Matt Caswell*

 * The security callback, which can be customised by application code, supports
   the security operation SSL_SECOP_TMP_DH. One location of the "other" parameter
   was incorrectly passing a DH object. It now passed an EVP_PKEY in all cases.

   *Matt Caswell*

 * Add PKCS7_get_octet_string() and PKCS7_type_is_other() to the public
   interface. Their functionality remains unchanged.

   *Jordan Montgomery*

 * Added new option for 'openssl list', '-providers', which will display the
   list of loaded providers, their names, version and status.  It optionally
   displays their gettable parameters.

   *Paul Dale*

 * Removed EVP_PKEY_set_alias_type().

   *Richard Levitte*

 * Deprecated `EVP_PKEY_CTX_set_rsa_keygen_pubexp()` and introduced
   `EVP_PKEY_CTX_set1_rsa_keygen_pubexp()`, which is now preferred.

   *Jeremy Walch*

 * Changed all "STACK" functions to be macros instead of inline functions. Macro
   parameters are still checked for type safety at compile time via helper
   inline functions.

   *Matt Caswell*

 * Remove the RAND_DRBG API

   *Paul Dale and Matthias St. Pierre*

 * Allow `SSL_set1_host()` and `SSL_add1_host()` to take IP literal addresses
   as well as actual hostnames.

   *David Woodhouse*

 * The 'MinProtocol' and 'MaxProtocol' configuration commands now silently
   ignore TLS protocol version bounds when configuring DTLS-based contexts, and
   conversely, silently ignore DTLS protocol version bounds when configuring
   TLS-based contexts.  The commands can be repeated to set bounds of both
   types.  The same applies with the corresponding "min_protocol" and
   "max_protocol" command-line switches, in case some application uses both TLS
   and DTLS.

   SSL_CTX instances that are created for a fixed protocol version (e.g.
   `TLSv1_server_method()`) also silently ignore version bounds.  Previously
   attempts to apply bounds to these protocol versions would result in an
   error.  Now only the "version-flexible" SSL_CTX instances are subject to
   limits in configuration files in command-line options.

   *Viktor Dukhovni*

 * Deprecated the `ENGINE` API.  Engines should be replaced with providers
   going forward.

   *Paul Dale*

 * Reworked the recorded ERR codes to make better space for system errors.
   To distinguish them, the macro `ERR_SYSTEM_ERROR()` indicates if the
   given code is a system error (true) or an OpenSSL error (false).

   *Richard Levitte*

 * Reworked the test perl framework to better allow parallel testing.

   *Nicola Tuveri and David von Oheimb*

 * Added ciphertext stealing algorithms AES-128-CBC-CTS, AES-192-CBC-CTS and
   AES-256-CBC-CTS to the providers. CS1, CS2 and CS3 variants are supported.

   *Shane Lontis*

 * 'Configure' has been changed to figure out the configuration target if
   none is given on the command line.  Consequently, the 'config' script is
   now only a mere wrapper.  All documentation is changed to only mention
   'Configure'.

   *Rich Salz and Richard Levitte*

 * Added a library context `OSSL_LIB_CTX` that applications as well as
   other libraries can use to form a separate context within which
   libcrypto operations are performed.

   *Richard Levitte*

 * Added various `_ex` functions to the OpenSSL API that support using
   a non-default `OSSL_LIB_CTX`.

   *OpenSSL team*

 * Handshake now fails if Extended Master Secret extension is dropped
   on renegotiation.

   *Tomáš Mráz*

 * Dropped interactive mode from the `openssl` program.

   *Richard Levitte*

 * Deprecated `EVP_PKEY_cmp()` and `EVP_PKEY_cmp_parameters()`.

   *David von Oheimb and Shane Lontis*

 * Deprecated `EC_METHOD_get_field_type()`.

   *Billy Bob Brumley*

 * Deprecated EC_GFp_simple_method(), EC_GFp_mont_method(),
   EC_GF2m_simple_method(), EC_GFp_nist_method(), EC_GFp_nistp224_method()
   EC_GFp_nistp256_method(), and EC_GFp_nistp521_method().

   *Billy Bob Brumley*

 * Deprecated EC_GROUP_new(), EC_GROUP_method_of(), and EC_POINT_method_of().

   *Billy Bob Brumley*

 * Add CAdES-BES signature verification support, mostly derived
   from ESSCertIDv2 TS (RFC 5816) contribution by Marek Klein.

   *Filipe Raimundo da Silva*

 * Add CAdES-BES signature scheme and attributes support (RFC 5126) to CMS API.

   *Antonio Iacono*

 * Added the AuthEnvelopedData content type structure (RFC 5083) with AES-GCM
   parameter (RFC 5084) for the Cryptographic Message Syntax (CMS).

   *Jakub Zelenka*

 * Deprecated EC_POINT_make_affine() and EC_POINTs_make_affine().

   *Billy Bob Brumley*

 * Deprecated EC_GROUP_precompute_mult(), EC_GROUP_have_precompute_mult(), and
   EC_KEY_precompute_mult().

   *Billy Bob Brumley*

 * Deprecated EC_POINTs_mul().

   *Billy Bob Brumley*

 * Removed FIPS_mode() and FIPS_mode_set().

   *Shane Lontis*

 * The SSL option SSL_OP_IGNORE_UNEXPECTED_EOF is introduced.

   *Dmitry Belyavskiy*

 * Deprecated EC_POINT_set_Jprojective_coordinates_GFp() and
   EC_POINT_get_Jprojective_coordinates_GFp().

   *Billy Bob Brumley*

 * Added OSSL_PARAM_BLD to the public interface.  This allows OSSL_PARAM
   arrays to be more easily constructed via a series of utility functions.
   Create a parameter builder using OSSL_PARAM_BLD_new(), add parameters using
   the various push functions and finally convert to a passable OSSL_PARAM
   array using OSSL_PARAM_BLD_to_param().

   *Paul Dale*

 * The security strength of SHA1 and MD5 based signatures in TLS has been
   reduced.

   *Kurt Roeckx*

 * Added EVP_PKEY_set_type_by_keymgmt(), to initialise an EVP_PKEY to
   contain a provider side internal key.

   *Richard Levitte*

 * ASN1_verify(), ASN1_digest() and ASN1_sign() have been deprecated.

   *Richard Levitte*

 * Project text documents not yet having a proper file name extension
   (`HACKING`, `LICENSE`, `NOTES*`, `README*`, `VERSION`) have been renamed to
   `*.md` as far as reasonable, else `*.txt`, for better use with file managers.

   *David von Oheimb*

 * The main project documents (README, NEWS, CHANGES, INSTALL, SUPPORT)
   have been converted to Markdown with the goal to produce documents
   which not only look pretty when viewed online in the browser, but
   remain well readable inside a plain text editor.

   To achieve this goal, a 'minimalistic' Markdown style has been applied
   which avoids formatting elements that interfere too much with the
   reading flow in the text file. For example, it

   * avoids [ATX headings][] and uses [setext headings][] instead
     (which works for `<h1>` and `<h2>` headings only).
   * avoids [inline links][] and uses [reference links][] instead.
   * avoids [fenced code blocks][] and uses [indented code blocks][] instead.

     [ATX headings]:         https://github.github.com/gfm/#atx-headings
     [setext headings]:      https://github.github.com/gfm/#setext-headings
     [inline links]:         https://github.github.com/gfm/#inline-link
     [reference links]:      https://github.github.com/gfm/#reference-link
     [fenced code blocks]:   https://github.github.com/gfm/#fenced-code-blocks
     [indented code blocks]: https://github.github.com/gfm/#indented-code-blocks

   *Matthias St. Pierre*

 * The test suite is changed to preserve results of each test recipe.
   A new directory test-runs/ with subdirectories named like the
   test recipes are created in the build tree for this purpose.

   *Richard Levitte*

 * Added an implementation of CMP and CRMF (RFC 4210, RFC 4211 RFC 6712).
   This adds `crypto/cmp/`, `crpyto/crmf/`, `apps/cmp.c`, and `test/cmp_*`.
   See L<openssl-cmp(1)> and L<OSSL_CMP_exec_IR_ses(3)> as starting points.

   *David von Oheimb, Martin Peylo*

 * Generalized the HTTP client code from `crypto/ocsp/` into `crpyto/http/`.
   It supports arbitrary request and response content types, GET redirection,
   TLS, connections via HTTP(S) proxies, connections and exchange via
   user-defined BIOs (allowing implicit connections), persistent connections,
   and timeout checks.  See L<OSSL_HTTP_transfer(3)> etc. for details.
   The legacy OCSP-focused (and only partly documented) API
   is retained for backward compatibility, while most of it is deprecated.

   *David von Oheimb*

 * Added `util/check-format.pl`, a tool for checking adherence to the
   OpenSSL coding style <https://www.openssl.org/policies/codingstyle.html>.
   The checks performed are incomplete and yield some false positives.
   Still the tool should be useful for detecting most typical glitches.

   *David von Oheimb*

 * `BIO_do_connect()` and `BIO_do_handshake()` have been extended:
   If domain name resolution yields multiple IP addresses all of them are tried
   after `connect()` failures.

   *David von Oheimb*

 * All of the low-level RSA functions have been deprecated.

   *Paul Dale*

 * X509 certificates signed using SHA1 are no longer allowed at security
   level 1 and above.

   *Kurt Roeckx*

 * The command line utilities dhparam, dsa, gendsa and dsaparam have been
   modified to use PKEY APIs.  These commands are now in maintenance mode
   and no new features will be added to them.

   *Paul Dale*

 * The command line utility rsautl has been deprecated.

   *Paul Dale*

 * The command line utilities genrsa and rsa have been modified to use PKEY
   APIs. They now write PKCS#8 keys by default. These commands are now in
   maintenance mode and no new features will be added to them.

   *Paul Dale*

 * All of the low-level DH functions have been deprecated.

   *Paul Dale and Matt Caswell*

 * All of the low-level DSA functions have been deprecated.

   *Paul Dale*

 * Reworked the treatment of EC EVP_PKEYs with the SM2 curve to
   automatically become EVP_PKEY_SM2 rather than EVP_PKEY_EC.

   *Richard Levitte*

 * Deprecated low-level ECDH and ECDSA functions.

   *Paul Dale*

 * Deprecated EVP_PKEY_decrypt_old() and EVP_PKEY_encrypt_old().

   *Richard Levitte*

 * Enhanced the documentation of EVP_PKEY_get_size(), EVP_PKEY_get_bits()
   and EVP_PKEY_get_security_bits().  Especially EVP_PKEY_get_size() needed
   a new formulation to include all the things it can be used for,
   as well as words of caution.

   *Richard Levitte*

 * The SSL_CTX_set_tlsext_ticket_key_cb(3) function has been deprecated.

   *Paul Dale*

 * All of the low-level HMAC functions have been deprecated.

   *Paul Dale and David von Oheimb*

 * Over two thousand fixes were made to the documentation, including:
   - Common options (such as -rand/-writerand, TLS version control, etc)
     were refactored and point to newly-enhanced descriptions in openssl.pod.
   - Added style conformance for all options (with help from Richard Levitte),
     documented all reported missing options, added a CI build to check
     that all options are documented and that no unimplemented options
     are documented.
   - Documented some internals, such as all use of environment variables.
   - Addressed all internal broken L<> references.

   *Rich Salz*

 * All of the low-level CMAC functions have been deprecated.

   *Paul Dale*

 * The low-level MD2, MD4, MD5, MDC2, RIPEMD160 and Whirlpool digest
   functions have been deprecated.

   *Paul Dale and David von Oheimb*

 * Corrected the documentation of the return values from the `EVP_DigestSign*`
   set of functions.  The documentation mentioned negative values for some
   errors, but this was never the case, so the mention of negative values
   was removed.

   Code that followed the documentation and thereby check with something
   like `EVP_DigestSignInit(...) <= 0` will continue to work undisturbed.

   *Richard Levitte*

 * All of the low-level cipher functions have been deprecated.

   *Matt Caswell and Paul Dale*

 * Removed include/openssl/opensslconf.h.in and replaced it with
   include/openssl/configuration.h.in, which differs in not including
   <openssl/macros.h>.  A short header include/openssl/opensslconf.h
   was added to include both.

   This allows internal hacks where one might need to modify the set
   of configured macros, for example this if deprecated symbols are
   still supposed to be available internally:

       #include <openssl/configuration.h>

       #undef OPENSSL_NO_DEPRECATED
       #define OPENSSL_SUPPRESS_DEPRECATED

       #include <openssl/macros.h>

   This should not be used by applications that use the exported
   symbols, as that will lead to linking errors.

   *Richard Levitte*

 * Fixed an overflow bug in the x64_64 Montgomery squaring procedure
   used in exponentiation with 512-bit moduli. No EC algorithms are
   affected. Analysis suggests that attacks against 2-prime RSA1024,
   3-prime RSA1536, and DSA1024 as a result of this defect would be very
   difficult to perform and are not believed likely. Attacks against DH512
   are considered just feasible. However, for an attack the target would
   have to re-use the DH512 private key, which is not recommended anyway.
   Also applications directly using the low-level API BN_mod_exp may be
   affected if they use BN_FLG_CONSTTIME.
   ([CVE-2019-1551])

   *Andy Polyakov*

 * Most memory-debug features have been deprecated, and the functionality
   replaced with no-ops.

   *Rich Salz*

 * Added documentation for the STACK API.

   *Rich Salz*

 * Introduced a new method type and API, OSSL_ENCODER, to represent
   generic encoders.  These do the same sort of job that PEM writers
   and d2i functions do, but with support for methods supplied by
   providers, and the possibility for providers to support other
   formats as well.

   *Richard Levitte*

 * Introduced a new method type and API, OSSL_DECODER, to represent
   generic decoders.  These do the same sort of job that PEM readers
   and i2d functions do, but with support for methods supplied by
   providers, and the possibility for providers to support other
   formats as well.

   *Richard Levitte*

 * Added a .pragma directive to the syntax of configuration files, to
   allow varying behavior in a supported and predictable manner.
   Currently added pragma:

           .pragma dollarid:on

   This allows dollar signs to be a keyword character unless it's
   followed by a opening brace or parenthesis.  This is useful for
   platforms where dollar signs are commonly used in names, such as
   volume names and system directory names on VMS.

   *Richard Levitte*

 * Added functionality to create an EVP_PKEY from user data.

   *Richard Levitte*

 * Change the interpretation of the '--api' configuration option to
   mean that this is a desired API compatibility level with no
   further meaning.  The previous interpretation, that this would
   also mean to remove all deprecated symbols up to and including
   the given version, no requires that 'no-deprecated' is also used
   in the configuration.

   When building applications, the desired API compatibility level
   can be set with the OPENSSL_API_COMPAT macro like before.  For
   API compatibility version below 3.0, the old style numerical
   value is valid as before, such as -DOPENSSL_API_COMPAT=0x10100000L.
   For version 3.0 and on, the value is expected to be the decimal
   value calculated from the major and minor version like this:

           MAJOR * 10000 + MINOR * 100

   Examples:

           -DOPENSSL_API_COMPAT=30000             For 3.0
           -DOPENSSL_API_COMPAT=30200             For 3.2

   To hide declarations that are deprecated up to and including the
   given API compatibility level, -DOPENSSL_NO_DEPRECATED must be
   given when building the application as well.

   *Richard Levitte*

 * Added the X509_LOOKUP_METHOD called X509_LOOKUP_store, to allow
   access to certificate and CRL stores via URIs and OSSL_STORE
   loaders.

   This adds the following functions:

   - X509_LOOKUP_store()
   - X509_STORE_load_file()
   - X509_STORE_load_path()
   - X509_STORE_load_store()
   - SSL_add_store_cert_subjects_to_stack()
   - SSL_CTX_set_default_verify_store()
   - SSL_CTX_load_verify_file()
   - SSL_CTX_load_verify_dir()
   - SSL_CTX_load_verify_store()

   *Richard Levitte*

 * Added a new method to gather entropy on VMS, based on SYS$GET_ENTROPY.
   The presence of this system service is determined at run-time.

   *Richard Levitte*

 * Added functionality to create an EVP_PKEY context based on data
   for methods from providers.  This takes an algorithm name and a
   property query string and simply stores them, with the intent
   that any operation that uses this context will use those strings
   to fetch the needed methods implicitly, thereby making the port
   of application written for pre-3.0 OpenSSL easier.

   *Richard Levitte*

 * The undocumented function NCONF_WIN32() has been deprecated; for
   conversion details see the HISTORY section of doc/man5/config.pod

   *Rich Salz*

 * Introduced the new functions EVP_DigestSignInit_ex() and
   EVP_DigestVerifyInit_ex(). The macros EVP_DigestSignUpdate() and
   EVP_DigestVerifyUpdate() have been converted to functions. See the man
   pages for further details.

   *Matt Caswell*

 * Over two thousand fixes were made to the documentation, including:
   adding missing command flags, better style conformance, documentation
   of internals, etc.

   *Rich Salz, Richard Levitte*

 * s390x assembly pack: add hardware-support for P-256, P-384, P-521,
   X25519, X448, Ed25519 and Ed448.

   *Patrick Steuer*

 * Print all values for a PKCS#12 attribute with 'openssl pkcs12', not just
   the first value.

   *Jon Spillett*

 * Deprecated the public definition of `ERR_STATE` as well as the function
   `ERR_get_state()`.  This is done in preparation of making `ERR_STATE` an
   opaque type.

   *Richard Levitte*

 * Added ERR functionality to give callers access to the stored function
   names that have replaced the older function code based functions.

   New functions are ERR_peek_error_func(), ERR_peek_last_error_func(),
   ERR_peek_error_data(), ERR_peek_last_error_data(), ERR_get_error_all(),
   ERR_peek_error_all() and ERR_peek_last_error_all().

   Deprecate ERR functions ERR_get_error_line(), ERR_get_error_line_data(),
   ERR_peek_error_line_data(), ERR_peek_last_error_line_data() and
   ERR_func_error_string().

   *Richard Levitte*

 * Extended testing to be verbose for failing tests only.  The make variables
   VERBOSE_FAILURE or VF can be used to enable this:

           $ make VF=1 test                           # Unix
           $ mms /macro=(VF=1) test                   ! OpenVMS
           $ nmake VF=1 test                          # Windows

   *Richard Levitte*

 * Added the `-copy_extensions` option to the `x509` command for use with
   `-req` and `-x509toreq`. When given with the `copy` or `copyall` argument,
   all extensions in the request are copied to the certificate or vice versa.

   *David von Oheimb*, *Kirill Stefanenkov <kirill_stefanenkov@rambler.ru>*

 * Added the `-copy_extensions` option to the `req` command for use with
   `-x509`. When given with the `copy` or `copyall` argument,
   all extensions in the certification request are copied to the certificate.

   *David von Oheimb*

 * The `x509`, `req`, and `ca` commands now make sure that X.509v3 certificates
   they generate are by default RFC 5280 compliant in the following sense:
   There is a subjectKeyIdentifier extension with a hash value of the public key
   and for not self-signed certs there is an authorityKeyIdentifier extension
   with a keyIdentifier field or issuer information identifying the signing key.
   This is done unless some configuration overrides the new default behavior,
   such as `subjectKeyIdentifier = none` and `authorityKeyIdentifier = none`.

   *David von Oheimb*

 * Added several checks to `X509_verify_cert()` according to requirements in
   RFC 5280 in case `X509_V_FLAG_X509_STRICT` is set
   (which may be done by using the CLI option `-x509_strict`):
   * The basicConstraints of CA certificates must be marked critical.
   * CA certificates must explicitly include the keyUsage extension.
   * If a pathlenConstraint is given the key usage keyCertSign must be allowed.
   * The issuer name of any certificate must not be empty.
   * The subject name of CA certs, certs with keyUsage crlSign,
     and certs without subjectAlternativeName must not be empty.
   * If a subjectAlternativeName extension is given it must not be empty.
   * The signatureAlgorithm field and the cert signature must be consistent.
   * Any given authorityKeyIdentifier and any given subjectKeyIdentifier
     must not be marked critical.
   * The authorityKeyIdentifier must be given for X.509v3 certs
     unless they are self-signed.
   * The subjectKeyIdentifier must be given for all X.509v3 CA certs.

   *David von Oheimb*

 * Certificate verification using `X509_verify_cert()` meanwhile rejects EC keys
   with explicit curve parameters (specifiedCurve) as required by RFC 5480.

   *Tomáš Mráz*

 * For built-in EC curves, ensure an EC_GROUP built from the curve name is
   used even when parsing explicit parameters, when loading a encoded key
   or calling `EC_GROUP_new_from_ecpkparameters()`/
   `EC_GROUP_new_from_ecparameters()`.
   This prevents bypass of security hardening and performance gains,
   especially for curves with specialized EC_METHODs.
   By default, if a key encoded with explicit parameters is loaded and later
   encoded, the output is still encoded with explicit parameters, even if
   internally a "named" EC_GROUP is used for computation.

   *Nicola Tuveri*

 * Compute ECC cofactors if not provided during EC_GROUP construction. Before
   this change, EC_GROUP_set_generator would accept order and/or cofactor as
   NULL. After this change, only the cofactor parameter can be NULL. It also
   does some minimal sanity checks on the passed order.
   ([CVE-2019-1547])

   *Billy Bob Brumley*

 * Fixed a padding oracle in PKCS7_dataDecode and CMS_decrypt_set1_pkey.
   An attack is simple, if the first CMS_recipientInfo is valid but the
   second CMS_recipientInfo is chosen ciphertext. If the second
   recipientInfo decodes to PKCS #1 v1.5 form plaintext, the correct
   encryption key will be replaced by garbage, and the message cannot be
   decoded, but if the RSA decryption fails, the correct encryption key is
   used and the recipient will not notice the attack.
   As a work around for this potential attack the length of the decrypted
   key must be equal to the cipher default key length, in case the
   certificate is not given and all recipientInfo are tried out.
   The old behaviour can be re-enabled in the CMS code by setting the
   CMS_DEBUG_DECRYPT flag.

   *Bernd Edlinger*

 * Early start up entropy quality from the DEVRANDOM seed source has been
   improved for older Linux systems.  The RAND subsystem will wait for
   /dev/random to be producing output before seeding from /dev/urandom.
   The seeded state is stored for future library initialisations using
   a system global shared memory segment.  The shared memory identifier
   can be configured by defining OPENSSL_RAND_SEED_DEVRANDOM_SHM_ID to
   the desired value.  The default identifier is 114.

   *Paul Dale*

 * Revised BN_generate_prime_ex to not avoid factors 2..17863 in p-1
   when primes for RSA keys are computed.
   Since we previously always generated primes == 2 (mod 3) for RSA keys,
   the 2-prime and 3-prime RSA modules were easy to distinguish, since
   `N = p*q = 1 (mod 3)`, but `N = p*q*r = 2 (mod 3)`. Therefore, fingerprinting
   2-prime vs. 3-prime RSA keys was possible by computing N mod 3.
   This avoids possible fingerprinting of newly generated RSA modules.

   *Bernd Edlinger*

 * Correct the extended master secret constant on EBCDIC systems. Without this
   fix TLS connections between an EBCDIC system and a non-EBCDIC system that
   negotiate EMS will fail. Unfortunately this also means that TLS connections
   between EBCDIC systems with this fix, and EBCDIC systems without this
   fix will fail if they negotiate EMS.

   *Matt Caswell*

 * Changed the library initialisation so that the config file is now loaded
   by default. This was already the case for libssl. It now occurs for both
   libcrypto and libssl. Use the OPENSSL_INIT_NO_LOAD_CONFIG option to
   `OPENSSL_init_crypto()` to suppress automatic loading of a config file.

   *Matt Caswell*

 * Introduced new error raising macros, `ERR_raise()` and `ERR_raise_data()`,
   where the former acts as a replacement for `ERR_put_error()`, and the
   latter replaces the combination `ERR_put_error()` + `ERR_add_error_data()`.
   `ERR_raise_data()` adds more flexibility by taking a format string and
   an arbitrary number of arguments following it, to be processed with
   `BIO_snprintf()`.

   *Richard Levitte*

 * Introduced a new function, `OSSL_PROVIDER_available()`, which can be used
   to check if a named provider is loaded and available.  When called, it
   will also activate all fallback providers if such are still present.

   *Richard Levitte*

 * Enforce a minimum DH modulus size of 512 bits.

   *Bernd Edlinger*

 * Changed DH parameters to generate the order q subgroup instead of 2q.
   Previously generated DH parameters are still accepted by DH_check
   but DH_generate_key works around that by clearing bit 0 of the
   private key for those. This avoids leaking bit 0 of the private key.

   *Bernd Edlinger*

 * Significantly reduce secure memory usage by the randomness pools.

   *Paul Dale*

 * `{CRYPTO,OPENSSL}_mem_debug_{push,pop}` are now no-ops and have been
   deprecated.

   *Rich Salz*

 * A new type, EVP_KEYEXCH, has been introduced to represent key exchange
   algorithms. An implementation of a key exchange algorithm can be obtained
   by using the function EVP_KEYEXCH_fetch(). An EVP_KEYEXCH algorithm can be
   used in a call to EVP_PKEY_derive_init_ex() which works in a similar way to
   the older EVP_PKEY_derive_init() function. See the man pages for the new
   functions for further details.

   *Matt Caswell*

 * The EVP_PKEY_CTX_set_dh_pad() macro has now been converted to a function.

   *Matt Caswell*

 * Removed the function names from error messages and deprecated the
   xxx_F_xxx define's.

   *Richard Levitte*

 * Removed NextStep support and the macro OPENSSL_UNISTD

   *Rich Salz*

 * Removed DES_check_key.  Also removed OPENSSL_IMPLEMENT_GLOBAL,
   OPENSSL_GLOBAL_REF, OPENSSL_DECLARE_GLOBAL.
   Also removed "export var as function" capability; we do not export
   variables, only functions.

   *Rich Salz*

 * RC5_32_set_key has been changed to return an int type, with 0 indicating
   an error and 1 indicating success. In previous versions of OpenSSL this
   was a void type. If a key was set longer than the maximum possible this
   would crash.

   *Matt Caswell*

 * Support SM2 signing and verification schemes with X509 certificate.

   *Paul Yang*

 * Use SHA256 as the default digest for TS query in the `ts` app.

   *Tomáš Mráz*

 * Change PBKDF2 to conform to SP800-132 instead of the older PKCS5 RFC2898.

   *Shane Lontis*

 * Default cipher lists/suites are now available via a function, the
   #defines are deprecated.

   *Todd Short*

 * Add target VC-WIN32-UWP, VC-WIN64A-UWP, VC-WIN32-ARM-UWP and
   VC-WIN64-ARM-UWP in Windows OneCore target for making building libraries
   for Windows Store apps easier. Also, the "no-uplink" option has been added.

   *Kenji Mouri*

 * Join the directories crypto/x509 and crypto/x509v3

   *Richard Levitte*

 * Added command 'openssl kdf' that uses the EVP_KDF API.

   *Shane Lontis*

 * Added command 'openssl mac' that uses the EVP_MAC API.

   *Shane Lontis*

 * Added OPENSSL_info() to get diverse built-in OpenSSL data, such
   as default directories.  Also added the command 'openssl info'
   for scripting purposes.

   *Richard Levitte*

 * The functions AES_ige_encrypt() and AES_bi_ige_encrypt() have been
   deprecated.

   *Matt Caswell*

 * Add prediction resistance to the DRBG reseeding process.

   *Paul Dale*

 * Limit the number of blocks in a data unit for AES-XTS to 2^20 as
   mandated by IEEE Std 1619-2018.

   *Paul Dale*

 * Added newline escaping functionality to a filename when using openssl dgst.
   This output format is to replicate the output format found in the `*sum`
   checksum programs. This aims to preserve backward compatibility.

   *Matt Eaton, Richard Levitte, and Paul Dale*

 * Removed the heartbeat message in DTLS feature, as it has very
   little usage and doesn't seem to fulfill a valuable purpose.
   The configuration option is now deprecated.

   *Richard Levitte*

 * Changed the output of 'openssl {digestname} < file' to display the
   digest name in its output.

   *Richard Levitte*

 * Added a new generic trace API which provides support for enabling
   instrumentation through trace output.

   *Richard Levitte & Matthias St. Pierre*

 * Added build tests for C++.  These are generated files that only do one
   thing, to include one public OpenSSL head file each.  This tests that
   the public header files can be usefully included in a C++ application.

   This test isn't enabled by default.  It can be enabled with the option
   'enable-buildtest-c++'.

   *Richard Levitte*

 * Added KB KDF (EVP_KDF_KB) to EVP_KDF.

   *Robbie Harwood*

 * Added SSH KDF (EVP_KDF_SSHKDF) and KRB5 KDF (EVP_KDF_KRB5KDF) to EVP_KDF.

   *Simo Sorce*

 * Added Single Step KDF (EVP_KDF_SS), X963 KDF, and X942 KDF to EVP_KDF.

   *Shane Lontis*

 * Added KMAC to EVP_MAC.

   *Shane Lontis*

 * Added property based algorithm implementation selection framework to
   the core.

   *Paul Dale*

 * Added SCA hardening for modular field inversion in EC_GROUP through
   a new dedicated field_inv() pointer in EC_METHOD.
   This also addresses a leakage affecting conversions from projective
   to affine coordinates.

   *Billy Bob Brumley, Nicola Tuveri*

 * Added EVP_KDF, an EVP layer KDF API, to simplify adding KDF and PRF
   implementations.  This includes an EVP_PKEY to EVP_KDF bridge for
   those algorithms that were already supported through the EVP_PKEY API
   (scrypt, TLS1 PRF and HKDF).  The low-level KDF functions for PBKDF2
   and scrypt are now wrappers that call EVP_KDF.

   *David Makepeace*

 * Build devcrypto engine as a dynamic engine.

   *Eneas U de Queiroz*

 * Add keyed BLAKE2 to EVP_MAC.

   *Antoine Salon*

 * Fix a bug in the computation of the endpoint-pair shared secret used
   by DTLS over SCTP. This breaks interoperability with older versions
   of OpenSSL like OpenSSL 1.1.0 and OpenSSL 1.0.2. There is a runtime
   switch SSL_MODE_DTLS_SCTP_LABEL_LENGTH_BUG (off by default) enabling
   interoperability with such broken implementations. However, enabling
   this switch breaks interoperability with correct implementations.

 * Fix a use after free bug in d2i_X509_PUBKEY when overwriting a
   re-used X509_PUBKEY object if the second PUBKEY is malformed.

   *Bernd Edlinger*

 * Move strictness check from EVP_PKEY_asn1_new() to EVP_PKEY_asn1_add0().

   *Richard Levitte*

 * Changed the license to the Apache License v2.0.

   *Richard Levitte*

 * Switch to a new version scheme using three numbers MAJOR.MINOR.PATCH.

   - Major releases (indicated by incrementing the MAJOR release number)
     may introduce incompatible API/ABI changes.
   - Minor releases (indicated by incrementing the MINOR release number)
     may introduce new features but retain API/ABI compatibility.
   - Patch releases (indicated by incrementing the PATCH number)
     are intended for bug fixes and other improvements of existing
     features only (like improving performance or adding documentation)
     and retain API/ABI compatibility.

   *Richard Levitte*

 * Add support for RFC5297 SIV mode (siv128), including AES-SIV.

   *Todd Short*

 * Remove the 'dist' target and add a tarball building script.  The
   'dist' target has fallen out of use, and it shouldn't be
   necessary to configure just to create a source distribution.

   *Richard Levitte*

 * Recreate the OS390-Unix config target.  It no longer relies on a
   special script like it did for OpenSSL pre-1.1.0.

   *Richard Levitte*

 * Instead of having the source directories listed in Configure, add
   a 'build.info' keyword SUBDIRS to indicate what sub-directories to
   look into.

   *Richard Levitte*

 * Add GMAC to EVP_MAC.

   *Paul Dale*

 * Ported the HMAC, CMAC and SipHash EVP_PKEY_METHODs to EVP_MAC.

   *Richard Levitte*

 * Added EVP_MAC, an EVP layer MAC API, to simplify adding MAC
   implementations.  This includes a generic EVP_PKEY to EVP_MAC bridge,
   to facilitate the continued use of MACs through raw private keys in
   functionality such as `EVP_DigestSign*` and `EVP_DigestVerify*`.

   *Richard Levitte*

 * Deprecate ECDH_KDF_X9_62().

   *Antoine Salon*

 * Added EVP_PKEY_ECDH_KDF_X9_63 and ecdh_KDF_X9_63() as replacements for
   the EVP_PKEY_ECDH_KDF_X9_62 KDF type and ECDH_KDF_X9_62(). The old names
   are retained for backwards compatibility.

   *Antoine Salon*

 * AES-XTS mode now enforces that its two keys are different to mitigate
   the attacked described in "Efficient Instantiations of Tweakable
   Blockciphers and Refinements to Modes OCB and PMAC" by Phillip Rogaway.
   Details of this attack can be obtained from:
   <http://web.cs.ucdavis.edu/%7Erogaway/papers/offsets.pdf>

   *Paul Dale*

 * Rename the object files, i.e. give them other names than in previous
   versions.  Their names now include the name of the final product, as
   well as its type mnemonic (bin, lib, shlib).

   *Richard Levitte*

 * Added new option for 'openssl list', '-objects', which will display the
   list of built in objects, i.e. OIDs with names.

   *Richard Levitte*

 * Added the options `-crl_lastupdate` and `-crl_nextupdate` to `openssl ca`,
   allowing the `lastUpdate` and `nextUpdate` fields in the generated CRL to
   be set explicitly.

   *Chris Novakovic*

 * Added support for Linux Kernel TLS data-path. The Linux Kernel data-path
   improves application performance by removing data copies and providing
   applications with zero-copy system calls such as sendfile and splice.

   *Boris Pismenny*

 * The SSL option SSL_OP_CLEANSE_PLAINTEXT is introduced.

   *Martin Elshuber*

 * `PKCS12_parse` now maintains the order of the parsed certificates
   when outputting them via `*ca` (rather than reversing it).

   *David von Oheimb*

 * Deprecated pthread fork support methods.

   *Randall S. Becker*

 * Added support for FFDHE key exchange in TLS 1.3.

   *Raja Ashok*

 * Added a new concept for OpenSSL plugability: providers.  This
   functionality is designed to replace the ENGINE API and ENGINE
   implementations, and to be much more dynamic, allowing provider
   authors to introduce new algorithms among other things, as long as
   there's an API that supports the algorithm type.

   With this concept comes a new core API for interaction between
   libcrypto and provider implementations.  Public libcrypto functions
   that want to use providers do so through this core API.

   The main documentation for this core API is found in
   doc/man7/provider.pod, doc/man7/provider-base.pod, and they in turn
   refer to other manuals describing the API specific for supported
   algorithm types (also called operations).

   *The OpenSSL team*

OpenSSL 1.1.1
-------------

### Changes between 1.1.1l and 1.1.1m [xx XXX xxxx]

 * Avoid loading of a dynamic engine twice.

   *Bernd Edlinger*

 * Prioritise DANE TLSA issuer certs over peer certs

   *Viktor Dukhovni*

 * Fixed random API for MacOS prior to 10.12

   These MacOS versions don't support the CommonCrypto APIs

   *Lenny Primak*

### Changes between 1.1.1k and 1.1.1l [24 Aug 2021]

 * Fixed an SM2 Decryption Buffer Overflow.

   In order to decrypt SM2 encrypted data an application is expected to
   call the API function EVP_PKEY_decrypt(). Typically an application will
   call this function twice. The first time, on entry, the "out" parameter
   can be NULL and, on exit, the "outlen" parameter is populated with the
   buffer size required to hold the decrypted plaintext. The application
   can then allocate a sufficiently sized buffer and call EVP_PKEY_decrypt()
   again, but this time passing a non-NULL value for the "out" parameter.

   A bug in the implementation of the SM2 decryption code means that the
   calculation of the buffer size required to hold the plaintext returned
   by the first call to EVP_PKEY_decrypt() can be smaller than the actual
   size required by the second call. This can lead to a buffer overflow
   when EVP_PKEY_decrypt() is called by the application a second time with
   a buffer that is too small.

   A malicious attacker who is able present SM2 content for decryption to
   an application could cause attacker chosen data to overflow the buffer
   by up to a maximum of 62 bytes altering the contents of other data held
   after the buffer, possibly changing application behaviour or causing
   the application to crash. The location of the buffer is application
   dependent but is typically heap allocated.
   ([CVE-2021-3711])

   *Matt Caswell*

 * Fixed various read buffer overruns processing ASN.1 strings

   ASN.1 strings are represented internally within OpenSSL as an ASN1_STRING
   structure which contains a buffer holding the string data and a field
   holding the buffer length. This contrasts with normal C strings which
   are represented as a buffer for the string data which is terminated
   with a NUL (0) byte.

   Although not a strict requirement, ASN.1 strings that are parsed using
   OpenSSL's own "d2i" functions (and other similar parsing functions) as
   well as any string whose value has been set with the ASN1_STRING_set()
   function will additionally NUL terminate the byte array in the
   ASN1_STRING structure.

   However, it is possible for applications to directly construct valid
   ASN1_STRING structures which do not NUL terminate the byte array by
   directly setting the "data" and "length" fields in the ASN1_STRING
   array. This can also happen by using the ASN1_STRING_set0() function.

   Numerous OpenSSL functions that print ASN.1 data have been found to
   assume that the ASN1_STRING byte array will be NUL terminated, even
   though this is not guaranteed for strings that have been directly
   constructed. Where an application requests an ASN.1 structure to be
   printed, and where that ASN.1 structure contains ASN1_STRINGs that have
   been directly constructed by the application without NUL terminating
   the "data" field, then a read buffer overrun can occur.

   The same thing can also occur during name constraints processing
   of certificates (for example if a certificate has been directly
   constructed by the application instead of loading it via the OpenSSL
   parsing functions, and the certificate contains non NUL terminated
   ASN1_STRING structures). It can also occur in the X509_get1_email(),
   X509_REQ_get1_email() and X509_get1_ocsp() functions.

   If a malicious actor can cause an application to directly construct an
   ASN1_STRING and then process it through one of the affected OpenSSL
   functions then this issue could be hit. This might result in a crash
   (causing a Denial of Service attack). It could also result in the
   disclosure of private memory contents (such as private keys, or
   sensitive plaintext).
   ([CVE-2021-3712])

   *Matt Caswell*

### Changes between 1.1.1j and 1.1.1k [25 Mar 2021]

 * Fixed a problem with verifying a certificate chain when using the
   X509_V_FLAG_X509_STRICT flag. This flag enables additional security checks of
   the certificates present in a certificate chain. It is not set by default.

   Starting from OpenSSL version 1.1.1h a check to disallow certificates in
   the chain that have explicitly encoded elliptic curve parameters was added
   as an additional strict check.

   An error in the implementation of this check meant that the result of a
   previous check to confirm that certificates in the chain are valid CA
   certificates was overwritten. This effectively bypasses the check
   that non-CA certificates must not be able to issue other certificates.

   If a "purpose" has been configured then there is a subsequent opportunity
   for checks that the certificate is a valid CA.  All of the named "purpose"
   values implemented in libcrypto perform this check.  Therefore, where
   a purpose is set the certificate chain will still be rejected even when the
   strict flag has been used. A purpose is set by default in libssl client and
   server certificate verification routines, but it can be overridden or
   removed by an application.

   In order to be affected, an application must explicitly set the
   X509_V_FLAG_X509_STRICT verification flag and either not set a purpose
   for the certificate verification or, in the case of TLS client or server
   applications, override the default purpose.
   ([CVE-2021-3450])

   *Tomáš Mráz*

 * Fixed an issue where an OpenSSL TLS server may crash if sent a maliciously
   crafted renegotiation ClientHello message from a client. If a TLSv1.2
   renegotiation ClientHello omits the signature_algorithms extension (where it
   was present in the initial ClientHello), but includes a
   signature_algorithms_cert extension then a NULL pointer dereference will
   result, leading to a crash and a denial of service attack.

   A server is only vulnerable if it has TLSv1.2 and renegotiation enabled
   (which is the default configuration). OpenSSL TLS clients are not impacted by
   this issue.
   ([CVE-2021-3449])

   *Peter Kästle and Samuel Sapalski*

### Changes between 1.1.1i and 1.1.1j [16 Feb 2021]

 * Fixed the X509_issuer_and_serial_hash() function. It attempts to
   create a unique hash value based on the issuer and serial number data
   contained within an X509 certificate. However, it was failing to correctly
   handle any errors that may occur while parsing the issuer field (which might
   occur if the issuer field is maliciously constructed). This may subsequently
   result in a NULL pointer deref and a crash leading to a potential denial of
   service attack.
   ([CVE-2021-23841])

   *Matt Caswell*

 * Fixed the RSA_padding_check_SSLv23() function and the RSA_SSLV23_PADDING
   padding mode to correctly check for rollback attacks. This is considered a
   bug in OpenSSL 1.1.1 because it does not support SSLv2. In 1.0.2 this is
   CVE-2021-23839.

   *Matt Caswell*

   Fixed the EVP_CipherUpdate, EVP_EncryptUpdate and EVP_DecryptUpdate
   functions. Previously they could overflow the output length argument in some
   cases where the input length is close to the maximum permissible length for
   an integer on the platform. In such cases the return value from the function
   call would be 1 (indicating success), but the output length value would be
   negative. This could cause applications to behave incorrectly or crash.
   ([CVE-2021-23840])

   *Matt Caswell*

 * Fixed SRP_Calc_client_key so that it runs in constant time. The previous
   implementation called BN_mod_exp without setting BN_FLG_CONSTTIME. This
   could be exploited in a side channel attack to recover the password. Since
   the attack is local host only this is outside of the current OpenSSL
   threat model and therefore no CVE is assigned.

   Thanks to Mohammed Sabt and Daniel De Almeida Braga for reporting this
   issue.

   *Matt Caswell*

### Changes between 1.1.1h and 1.1.1i [8 Dec 2020]

 * Fixed NULL pointer deref in the GENERAL_NAME_cmp function
   This function could crash if both GENERAL_NAMEs contain an EDIPARTYNAME.
    If an attacker can control both items being compared  then this could lead
    to a possible denial of service attack. OpenSSL itself uses the
    GENERAL_NAME_cmp function for two purposes:
    1) Comparing CRL distribution point names between an available CRL and a
       CRL distribution point embedded in an X509 certificate
    2) When verifying that a timestamp response token signer matches the
       timestamp authority name (exposed via the API functions
       TS_RESP_verify_response and TS_RESP_verify_token)
   ([CVE-2020-1971])

   *Matt Caswell*

### Changes between 1.1.1g and 1.1.1h [22 Sep 2020]

 * Certificates with explicit curve parameters are now disallowed in
   verification chains if the X509_V_FLAG_X509_STRICT flag is used.

   *Tomáš Mráz*

 * The 'MinProtocol' and 'MaxProtocol' configuration commands now silently
   ignore TLS protocol version bounds when configuring DTLS-based contexts, and
   conversely, silently ignore DTLS protocol version bounds when configuring
   TLS-based contexts.  The commands can be repeated to set bounds of both
   types.  The same applies with the corresponding "min_protocol" and
   "max_protocol" command-line switches, in case some application uses both TLS
   and DTLS.

   SSL_CTX instances that are created for a fixed protocol version (e.g.
   TLSv1_server_method()) also silently ignore version bounds.  Previously
   attempts to apply bounds to these protocol versions would result in an
   error.  Now only the "version-flexible" SSL_CTX instances are subject to
   limits in configuration files in command-line options.

   *Viktor Dukhovni*

 * Handshake now fails if Extended Master Secret extension is dropped
   on renegotiation.

   *Tomáš Mráz*

 * The Oracle Developer Studio compiler will start reporting deprecated APIs

### Changes between 1.1.1f and 1.1.1g [21 Apr 2020]

 * Fixed segmentation fault in SSL_check_chain()
   Server or client applications that call the SSL_check_chain() function
   during or after a TLS 1.3 handshake may crash due to a NULL pointer
   dereference as a result of incorrect handling of the
   "signature_algorithms_cert" TLS extension. The crash occurs if an invalid
   or unrecognised signature algorithm is received from the peer. This could
   be exploited by a malicious peer in a Denial of Service attack.
   ([CVE-2020-1967])

   *Benjamin Kaduk*

 * Added AES consttime code for no-asm configurations
   an optional constant time support for AES was added
   when building openssl for no-asm.
   Enable with: ./config no-asm -DOPENSSL_AES_CONST_TIME
   Disable with: ./config no-asm -DOPENSSL_NO_AES_CONST_TIME
   At this time this feature is by default disabled.
   It will be enabled by default in 3.0.

   *Bernd Edlinger*

### Changes between 1.1.1e and 1.1.1f [31 Mar 2020]

 * Revert the change of EOF detection while reading in libssl to avoid
   regressions in applications depending on the current way of reporting
   the EOF. As the existing method is not fully accurate the change to
   reporting the EOF via SSL_ERROR_SSL is kept on the current development
   branch and will be present in the 3.0 release.

   *Tomáš Mráz*

 * Revised BN_generate_prime_ex to not avoid factors 3..17863 in p-1
   when primes for RSA keys are computed.
   Since we previously always generated primes == 2 (mod 3) for RSA keys,
   the 2-prime and 3-prime RSA modules were easy to distinguish, since
   N = p*q = 1 (mod 3), but N = p*q*r = 2 (mod 3). Therefore, fingerprinting
   2-prime vs. 3-prime RSA keys was possible by computing N mod 3.
   This avoids possible fingerprinting of newly generated RSA modules.

   *Bernd Edlinger*

### Changes between 1.1.1d and 1.1.1e [17 Mar 2020]

 * Properly detect EOF while reading in libssl. Previously if we hit an EOF
   while reading in libssl then we would report an error back to the
   application (SSL_ERROR_SYSCALL) but errno would be 0. We now add
   an error to the stack (which means we instead return SSL_ERROR_SSL) and
   therefore give a hint as to what went wrong.

   *Matt Caswell*

 * Check that ed25519 and ed448 are allowed by the security level. Previously
   signature algorithms not using an MD were not being checked that they were
   allowed by the security level.

   *Kurt Roeckx*

 * Fixed SSL_get_servername() behaviour. The behaviour of SSL_get_servername()
   was not quite right. The behaviour was not consistent between resumption
   and normal handshakes, and also not quite consistent with historical
   behaviour. The behaviour in various scenarios has been clarified and
   it has been updated to make it match historical behaviour as closely as
   possible.

   *Matt Caswell*

 * *[VMS only]* The header files that the VMS compilers include automatically,
   `__DECC_INCLUDE_PROLOGUE.H` and `__DECC_INCLUDE_EPILOGUE.H`, use pragmas
   that the C++ compiler doesn't understand.  This is a shortcoming in the
   compiler, but can be worked around with `__cplusplus` guards.

   C++ applications that use OpenSSL libraries must be compiled using the
   qualifier `/NAMES=(AS_IS,SHORTENED)` to be able to use all the OpenSSL
   functions.  Otherwise, only functions with symbols of less than 31
   characters can be used, as the linker will not be able to successfully
   resolve symbols with longer names.

   *Richard Levitte*

 * Added a new method to gather entropy on VMS, based on SYS$GET_ENTROPY.
   The presence of this system service is determined at run-time.

   *Richard Levitte*

 * Print all values for a PKCS#12 attribute with 'openssl pkcs12', not just
   the first value.

   *Jon Spillett*

### Changes between 1.1.1c and 1.1.1d [10 Sep 2019]

 * Fixed a fork protection issue. OpenSSL 1.1.1 introduced a rewritten random
   number generator (RNG). This was intended to include protection in the
   event of a fork() system call in order to ensure that the parent and child
   processes did not share the same RNG state. However, this protection was not
   being used in the default case.

   A partial mitigation for this issue is that the output from a high
   precision timer is mixed into the RNG state so the likelihood of a parent
   and child process sharing state is significantly reduced.

   If an application already calls OPENSSL_init_crypto() explicitly using
   OPENSSL_INIT_ATFORK then this problem does not occur at all.
   ([CVE-2019-1549])

   *Matthias St. Pierre*

 * For built-in EC curves, ensure an EC_GROUP built from the curve name is
   used even when parsing explicit parameters, when loading a encoded key
   or calling `EC_GROUP_new_from_ecpkparameters()`/
   `EC_GROUP_new_from_ecparameters()`.
   This prevents bypass of security hardening and performance gains,
   especially for curves with specialized EC_METHODs.
   By default, if a key encoded with explicit parameters is loaded and later
   encoded, the output is still encoded with explicit parameters, even if
   internally a "named" EC_GROUP is used for computation.

   *Nicola Tuveri*

 * Compute ECC cofactors if not provided during EC_GROUP construction. Before
   this change, EC_GROUP_set_generator would accept order and/or cofactor as
   NULL. After this change, only the cofactor parameter can be NULL. It also
   does some minimal sanity checks on the passed order.
   ([CVE-2019-1547])

   *Billy Bob Brumley*

 * Fixed a padding oracle in PKCS7_dataDecode and CMS_decrypt_set1_pkey.
   An attack is simple, if the first CMS_recipientInfo is valid but the
   second CMS_recipientInfo is chosen ciphertext. If the second
   recipientInfo decodes to PKCS #1 v1.5 form plaintext, the correct
   encryption key will be replaced by garbage, and the message cannot be
   decoded, but if the RSA decryption fails, the correct encryption key is
   used and the recipient will not notice the attack.
   As a work around for this potential attack the length of the decrypted
   key must be equal to the cipher default key length, in case the
   certificate is not given and all recipientInfo are tried out.
   The old behaviour can be re-enabled in the CMS code by setting the
   CMS_DEBUG_DECRYPT flag.
   ([CVE-2019-1563])

   *Bernd Edlinger*

 * Early start up entropy quality from the DEVRANDOM seed source has been
   improved for older Linux systems.  The RAND subsystem will wait for
   /dev/random to be producing output before seeding from /dev/urandom.
   The seeded state is stored for future library initialisations using
   a system global shared memory segment.  The shared memory identifier
   can be configured by defining OPENSSL_RAND_SEED_DEVRANDOM_SHM_ID to
   the desired value.  The default identifier is 114.

   *Paul Dale*

 * Correct the extended master secret constant on EBCDIC systems. Without this
   fix TLS connections between an EBCDIC system and a non-EBCDIC system that
   negotiate EMS will fail. Unfortunately this also means that TLS connections
   between EBCDIC systems with this fix, and EBCDIC systems without this
   fix will fail if they negotiate EMS.

   *Matt Caswell*

 * Use Windows installation paths in the mingw builds

   Mingw isn't a POSIX environment per se, which means that Windows
   paths should be used for installation.
   ([CVE-2019-1552])

   *Richard Levitte*

 * Changed DH_check to accept parameters with order q and 2q subgroups.
   With order 2q subgroups the bit 0 of the private key is not secret
   but DH_generate_key works around that by clearing bit 0 of the
   private key for those. This avoids leaking bit 0 of the private key.

   *Bernd Edlinger*

 * Significantly reduce secure memory usage by the randomness pools.

   *Paul Dale*

 * Revert the DEVRANDOM_WAIT feature for Linux systems

   The DEVRANDOM_WAIT feature added a select() call to wait for the
   /dev/random device to become readable before reading from the
   /dev/urandom device.

   It turned out that this change had negative side effects on
   performance which were not acceptable. After some discussion it
   was decided to revert this feature and leave it up to the OS
   resp. the platform maintainer to ensure a proper initialization
   during early boot time.

   *Matthias St. Pierre*

### Changes between 1.1.1b and 1.1.1c [28 May 2019]

 * Add build tests for C++.  These are generated files that only do one
   thing, to include one public OpenSSL head file each.  This tests that
   the public header files can be usefully included in a C++ application.

   This test isn't enabled by default.  It can be enabled with the option
   'enable-buildtest-c++'.

   *Richard Levitte*

 * Enable SHA3 pre-hashing for ECDSA and DSA.

   *Patrick Steuer*

 * Change the default RSA, DSA and DH size to 2048 bit instead of 1024.
   This changes the size when using the `genpkey` command when no size is given.
   It fixes an omission in earlier changes that changed all RSA, DSA and DH
   generation commands to use 2048 bits by default.

   *Kurt Roeckx*

 * Reorganize the manual pages to consistently have RETURN VALUES,
   EXAMPLES, SEE ALSO and HISTORY come in that order, and adjust
   util/fix-doc-nits accordingly.

   *Paul Yang, Joshua Lock*

 * Add the missing accessor EVP_PKEY_get0_engine()

   *Matt Caswell*

 * Have commands like `s_client` and `s_server` output the signature scheme
   along with other cipher suite parameters when debugging.

   *Lorinczy Zsigmond*

 * Make OPENSSL_config() error agnostic again.

   *Richard Levitte*

 * Do the error handling in RSA decryption constant time.

   *Bernd Edlinger*

 * Prevent over long nonces in ChaCha20-Poly1305.

   ChaCha20-Poly1305 is an AEAD cipher, and requires a unique nonce input
   for every encryption operation. RFC 7539 specifies that the nonce value
   (IV) should be 96 bits (12 bytes). OpenSSL allows a variable nonce length
   and front pads the nonce with 0 bytes if it is less than 12
   bytes. However it also incorrectly allows a nonce to be set of up to 16
   bytes. In this case only the last 12 bytes are significant and any
   additional leading bytes are ignored.

   It is a requirement of using this cipher that nonce values are
   unique. Messages encrypted using a reused nonce value are susceptible to
   serious confidentiality and integrity attacks. If an application changes
   the default nonce length to be longer than 12 bytes and then makes a
   change to the leading bytes of the nonce expecting the new value to be a
   new unique nonce then such an application could inadvertently encrypt
   messages with a reused nonce.

   Additionally the ignored bytes in a long nonce are not covered by the
   integrity guarantee of this cipher. Any application that relies on the
   integrity of these ignored leading bytes of a long nonce may be further
   affected. Any OpenSSL internal use of this cipher, including in SSL/TLS,
   is safe because no such use sets such a long nonce value. However user
   applications that use this cipher directly and set a non-default nonce
   length to be longer than 12 bytes may be vulnerable.

   This issue was reported to OpenSSL on 16th of March 2019 by Joran Dirk
   Greef of Ronomon.
   ([CVE-2019-1543])

   *Matt Caswell*

 * Add DEVRANDOM_WAIT feature for Linux systems

   On older Linux systems where the getrandom() system call is not available,
   OpenSSL normally uses the /dev/urandom device for seeding its CSPRNG.
   Contrary to getrandom(), the /dev/urandom device will not block during
   early boot when the kernel CSPRNG has not been seeded yet.

   To mitigate this known weakness, use select() to wait for /dev/random to
   become readable before reading from /dev/urandom.

 * Ensure that SM2 only uses SM3 as digest algorithm

   *Paul Yang*

### Changes between 1.1.1a and 1.1.1b [26 Feb 2019]

 * Change the info callback signals for the start and end of a post-handshake
   message exchange in TLSv1.3. In 1.1.1/1.1.1a we used SSL_CB_HANDSHAKE_START
   and SSL_CB_HANDSHAKE_DONE. Experience has shown that many applications get
   confused by this and assume that a TLSv1.2 renegotiation has started. This
   can break KeyUpdate handling. Instead we no longer signal the start and end
   of a post handshake message exchange (although the messages themselves are
   still signalled). This could break some applications that were expecting
   the old signals. However without this KeyUpdate is not usable for many
   applications.

   *Matt Caswell*

### Changes between 1.1.1 and 1.1.1a [20 Nov 2018]

 * Timing vulnerability in DSA signature generation

   The OpenSSL DSA signature algorithm has been shown to be vulnerable to a
   timing side channel attack. An attacker could use variations in the signing
   algorithm to recover the private key.

   This issue was reported to OpenSSL on 16th October 2018 by Samuel Weiser.
   ([CVE-2018-0734])

   *Paul Dale*

 * Timing vulnerability in ECDSA signature generation

   The OpenSSL ECDSA signature algorithm has been shown to be vulnerable to a
   timing side channel attack. An attacker could use variations in the signing
   algorithm to recover the private key.

   This issue was reported to OpenSSL on 25th October 2018 by Samuel Weiser.
   ([CVE-2018-0735])

   *Paul Dale*

 * Fixed the issue that RAND_add()/RAND_seed() silently discards random input
   if its length exceeds 4096 bytes. The limit has been raised to a buffer size
   of two gigabytes and the error handling improved.

   This issue was reported to OpenSSL by Dr. Falko Strenzke. It has been
   categorized as a normal bug, not a security issue, because the DRBG reseeds
   automatically and is fully functional even without additional randomness
   provided by the application.

### Changes between 1.1.0i and 1.1.1 [11 Sep 2018]

 * Add a new ClientHello callback. Provides a callback interface that gives
   the application the ability to adjust the nascent SSL object at the
   earliest stage of ClientHello processing, immediately after extensions have
   been collected but before they have been processed. In particular, this
   callback can adjust the supported TLS versions in response to the contents
   of the ClientHello

   *Benjamin Kaduk*

 * Add SM2 base algorithm support.

   *Jack Lloyd*

 * s390x assembly pack: add (improved) hardware-support for the following
   cryptographic primitives: sha3, shake, aes-gcm, aes-ccm, aes-ctr, aes-ofb,
   aes-cfb/cfb8, aes-ecb.

   *Patrick Steuer*

 * Make EVP_PKEY_asn1_new() a bit stricter about its input.  A NULL pem_str
   parameter is no longer accepted, as it leads to a corrupt table.  NULL
   pem_str is reserved for alias entries only.

   *Richard Levitte*

 * Use the new ec_scalar_mul_ladder scaffold to implement a specialized ladder
   step for prime curves. The new implementation is based on formulae from
   differential addition-and-doubling in homogeneous projective coordinates
   from Izu-Takagi "A fast parallel elliptic curve multiplication resistant
   against side channel attacks" and Brier-Joye "Weierstrass Elliptic Curves
   and Side-Channel Attacks" Eq. (8) for y-coordinate recovery, modified
   to work in projective coordinates.

   *Billy Bob Brumley, Nicola Tuveri*

 * Change generating and checking of primes so that the error rate of not
   being prime depends on the intended use based on the size of the input.
   For larger primes this will result in more rounds of Miller-Rabin.
   The maximal error rate for primes with more than 1080 bits is lowered
   to 2^-128.

   *Kurt Roeckx, Annie Yousar*

 * Increase the number of Miller-Rabin rounds for DSA key generating to 64.

   *Kurt Roeckx*

 * The 'tsget' script is renamed to 'tsget.pl', to avoid confusion when
   moving between systems, and to avoid confusion when a Windows build is
   done with mingw vs with MSVC.  For POSIX installs, there's still a
   symlink or copy named 'tsget' to avoid that confusion as well.

   *Richard Levitte*

 * Revert blinding in ECDSA sign and instead make problematic addition
   length-invariant. Switch even to fixed-length Montgomery multiplication.

   *Andy Polyakov*

 * Use the new ec_scalar_mul_ladder scaffold to implement a specialized ladder
   step for binary curves. The new implementation is based on formulae from
   differential addition-and-doubling in mixed Lopez-Dahab projective
   coordinates, modified to independently blind the operands.

   *Billy Bob Brumley, Sohaib ul Hassan, Nicola Tuveri*

 * Add a scaffold to optionally enhance the Montgomery ladder implementation
   for `ec_scalar_mul_ladder` (formerly `ec_mul_consttime`) allowing
   EC_METHODs to implement their own specialized "ladder step", to take
   advantage of more favorable coordinate systems or more efficient
   differential addition-and-doubling algorithms.

   *Billy Bob Brumley, Sohaib ul Hassan, Nicola Tuveri*

 * Modified the random device based seed sources to keep the relevant
   file descriptors open rather than reopening them on each access.
   This allows such sources to operate in a chroot() jail without
   the associated device nodes being available. This behaviour can be
   controlled using RAND_keep_random_devices_open().

   *Paul Dale*

 * Numerous side-channel attack mitigations have been applied. This may have
   performance impacts for some algorithms for the benefit of improved
   security. Specific changes are noted in this change log by their respective
   authors.

   *Matt Caswell*

 * AIX shared library support overhaul. Switch to AIX "natural" way of
   handling shared libraries, which means collecting shared objects of
   different versions and bitnesses in one common archive. This allows to
   mitigate conflict between 1.0 and 1.1 side-by-side installations. It
   doesn't affect the way 3rd party applications are linked, only how
   multi-version installation is managed.

   *Andy Polyakov*

 * Make ec_group_do_inverse_ord() more robust and available to other
   EC cryptosystems, so that irrespective of BN_FLG_CONSTTIME, SCA
   mitigations are applied to the fallback BN_mod_inverse().
   When using this function rather than BN_mod_inverse() directly, new
   EC cryptosystem implementations are then safer-by-default.

   *Billy Bob Brumley*

 * Add coordinate blinding for EC_POINT and implement projective
   coordinate blinding for generic prime curves as a countermeasure to
   chosen point SCA attacks.

   *Sohaib ul Hassan, Nicola Tuveri, Billy Bob Brumley*

 * Add blinding to ECDSA and DSA signatures to protect against side channel
   attacks discovered by Keegan Ryan (NCC Group).

   *Matt Caswell*

 * Enforce checking in the `pkeyutl` command to ensure that the input
   length does not exceed the maximum supported digest length when performing
   a sign, verify or verifyrecover operation.

   *Matt Caswell*

 * SSL_MODE_AUTO_RETRY is enabled by default. Applications that use blocking
   I/O in combination with something like select() or poll() will hang. This
   can be turned off again using SSL_CTX_clear_mode().
   Many applications do not properly handle non-application data records, and
   TLS 1.3 sends more of such records. Setting SSL_MODE_AUTO_RETRY works
   around the problems in those applications, but can also break some.
   It's recommended to read the manpages about SSL_read(), SSL_write(),
   SSL_get_error(), SSL_shutdown(), SSL_CTX_set_mode() and
   SSL_CTX_set_read_ahead() again.

   *Kurt Roeckx*

 * When unlocking a pass phrase protected PEM file or PKCS#8 container, we
   now allow empty (zero character) pass phrases.

   *Richard Levitte*

 * Apply blinding to binary field modular inversion and remove patent
   pending (OPENSSL_SUN_GF2M_DIV) BN_GF2m_mod_div implementation.

   *Billy Bob Brumley*

 * Deprecate ec2_mult.c and unify scalar multiplication code paths for
   binary and prime elliptic curves.

   *Billy Bob Brumley*

 * Remove ECDSA nonce padding: EC_POINT_mul is now responsible for
   constant time fixed point multiplication.

   *Billy Bob Brumley*

 * Revise elliptic curve scalar multiplication with timing attack
   defenses: ec_wNAF_mul redirects to a constant time implementation
   when computing fixed point and variable point multiplication (which
   in OpenSSL are mostly used with secret scalars in keygen, sign,
   ECDH derive operations).
   *Billy Bob Brumley, Nicola Tuveri, Cesar Pereida García,
    Sohaib ul Hassan*

 * Updated CONTRIBUTING

   *Rich Salz*

 * Updated DRBG / RAND to request nonce and additional low entropy
   randomness from the system.

   *Matthias St. Pierre*

 * Updated 'openssl rehash' to use OpenSSL consistent default.

   *Richard Levitte*

 * Moved the load of the ssl_conf module to libcrypto, which helps
   loading engines that libssl uses before libssl is initialised.

   *Matt Caswell*

 * Added EVP_PKEY_sign() and EVP_PKEY_verify() for EdDSA

   *Matt Caswell*

 * Fixed X509_NAME_ENTRY_set to get multi-valued RDNs right in all cases.

   *Ingo Schwarze, Rich Salz*

 * Added output of accepting IP address and port for 'openssl s_server'

   *Richard Levitte*

 * Added a new API for TLSv1.3 ciphersuites:
      SSL_CTX_set_ciphersuites()
      SSL_set_ciphersuites()

   *Matt Caswell*

 * Memory allocation failures consistently add an error to the error
   stack.

   *Rich Salz*

 * Don't use OPENSSL_ENGINES and OPENSSL_CONF environment values
   in libcrypto when run as setuid/setgid.

   *Bernd Edlinger*

 * Load any config file by default when libssl is used.

   *Matt Caswell*

 * Added new public header file <openssl/rand_drbg.h> and documentation
   for the RAND_DRBG API. See manual page RAND_DRBG(7) for an overview.

   *Matthias St. Pierre*

 * QNX support removed (cannot find contributors to get their approval
   for the license change).

   *Rich Salz*

 * TLSv1.3 replay protection for early data has been implemented. See the
   SSL_read_early_data() man page for further details.

   *Matt Caswell*

 * Separated TLSv1.3 ciphersuite configuration out from TLSv1.2 ciphersuite
   configuration. TLSv1.3 ciphersuites are not compatible with TLSv1.2 and
   below. Similarly TLSv1.2 ciphersuites are not compatible with TLSv1.3.
   In order to avoid issues where legacy TLSv1.2 ciphersuite configuration
   would otherwise inadvertently disable all TLSv1.3 ciphersuites the
   configuration has been separated out. See the ciphers man page or the
   SSL_CTX_set_ciphersuites() man page for more information.

   *Matt Caswell*

 * On POSIX (BSD, Linux, ...) systems the ocsp(1) command running
   in responder mode now supports the new "-multi" option, which
   spawns the specified number of child processes to handle OCSP
   requests.  The "-timeout" option now also limits the OCSP
   responder's patience to wait to receive the full client request
   on a newly accepted connection. Child processes are respawned
   as needed, and the CA index file is automatically reloaded
   when changed.  This makes it possible to run the "ocsp" responder
   as a long-running service, making the OpenSSL CA somewhat more
   feature-complete.  In this mode, most diagnostic messages logged
   after entering the event loop are logged via syslog(3) rather than
   written to stderr.

   *Viktor Dukhovni*

 * Added support for X448 and Ed448. Heavily based on original work by
   Mike Hamburg.

   *Matt Caswell*

 * Extend OSSL_STORE with capabilities to search and to narrow the set of
   objects loaded.  This adds the functions OSSL_STORE_expect() and
   OSSL_STORE_find() as well as needed tools to construct searches and
   get the search data out of them.

   *Richard Levitte*

 * Support for TLSv1.3 added. Note that users upgrading from an earlier
   version of OpenSSL should review their configuration settings to ensure
   that they are still appropriate for TLSv1.3. For further information see:
   <https://wiki.openssl.org/index.php/TLS1.3>

   *Matt Caswell*

 * Grand redesign of the OpenSSL random generator

   The default RAND method now utilizes an AES-CTR DRBG according to
   NIST standard SP 800-90Ar1. The new random generator is essentially
   a port of the default random generator from the OpenSSL FIPS 2.0
   object module. It is a hybrid deterministic random bit generator
   using an AES-CTR bit stream and which seeds and reseeds itself
   automatically using trusted system entropy sources.

   Some of its new features are:
    - Support for multiple DRBG instances with seed chaining.
    - The default RAND method makes use of a DRBG.
    - There is a public and private DRBG instance.
    - The DRBG instances are fork-safe.
    - Keep all global DRBG instances on the secure heap if it is enabled.
    - The public and private DRBG instance are per thread for lock free
      operation

   *Paul Dale, Benjamin Kaduk, Kurt Roeckx, Rich Salz, Matthias St. Pierre*

 * Changed Configure so it only says what it does and doesn't dump
   so much data.  Instead, ./configdata.pm should be used as a script
   to display all sorts of configuration data.

   *Richard Levitte*

 * Added processing of "make variables" to Configure.

   *Richard Levitte*

 * Added SHA512/224 and SHA512/256 algorithm support.

   *Paul Dale*

 * The last traces of Netware support, first removed in 1.1.0, have
   now been removed.

   *Rich Salz*

 * Get rid of Makefile.shared, and in the process, make the processing
   of certain files (rc.obj, or the .def/.map/.opt files produced from
   the ordinal files) more visible and hopefully easier to trace and
   debug (or make silent).

   *Richard Levitte*

 * Make it possible to have environment variable assignments as
   arguments to config / Configure.

   *Richard Levitte*

 * Add multi-prime RSA (RFC 8017) support.

   *Paul Yang*

 * Add SM3 implemented according to GB/T 32905-2016
   *Jack Lloyd <jack.lloyd@ribose.com>,*
   *Ronald Tse <ronald.tse@ribose.com>,*
   *Erick Borsboom <erick.borsboom@ribose.com>*

 * Add 'Maximum Fragment Length' TLS extension negotiation and support
   as documented in RFC6066.
   Based on a patch from Tomasz Moń

   *Filipe Raimundo da Silva*

 * Add SM4 implemented according to GB/T 32907-2016.
   *Jack Lloyd <jack.lloyd@ribose.com>,*
   *Ronald Tse <ronald.tse@ribose.com>,*
   *Erick Borsboom <erick.borsboom@ribose.com>*

 * Reimplement -newreq-nodes and ERR_error_string_n; the
   original author does not agree with the license change.

   *Rich Salz*

 * Add ARIA AEAD TLS support.

   *Jon Spillett*

 * Some macro definitions to support VS6 have been removed.  Visual
   Studio 6 has not worked since 1.1.0

   *Rich Salz*

 * Add ERR_clear_last_mark(), to allow callers to clear the last mark
   without clearing the errors.

   *Richard Levitte*

 * Add "atfork" functions.  If building on a system that without
   pthreads, see doc/man3/OPENSSL_fork_prepare.pod for application
   requirements.  The RAND facility now uses/requires this.

   *Rich Salz*

 * Add SHA3.

   *Andy Polyakov*

 * The UI API becomes a permanent and integral part of libcrypto, i.e.
   not possible to disable entirely.  However, it's still possible to
   disable the console reading UI method, UI_OpenSSL() (use UI_null()
   as a fallback).

   To disable, configure with 'no-ui-console'.  'no-ui' is still
   possible to use as an alias.  Check at compile time with the
   macro OPENSSL_NO_UI_CONSOLE.  The macro OPENSSL_NO_UI is still
   possible to check and is an alias for OPENSSL_NO_UI_CONSOLE.

   *Richard Levitte*

 * Add a STORE module, which implements a uniform and URI based reader of
   stores that can contain keys, certificates, CRLs and numerous other
   objects.  The main API is loosely based on a few stdio functions,
   and includes OSSL_STORE_open, OSSL_STORE_load, OSSL_STORE_eof,
   OSSL_STORE_error and OSSL_STORE_close.
   The implementation uses backends called "loaders" to implement arbitrary
   URI schemes.  There is one built in "loader" for the 'file' scheme.

   *Richard Levitte*

 * Add devcrypto engine.  This has been implemented against cryptodev-linux,
   then adjusted to work on FreeBSD 8.4 as well.
   Enable by configuring with 'enable-devcryptoeng'.  This is done by default
   on BSD implementations, as cryptodev.h is assumed to exist on all of them.

   *Richard Levitte*

 * Module names can prefixed with OSSL_ or OPENSSL_.  This affects
   util/mkerr.pl, which is adapted to allow those prefixes, leading to
   error code calls like this:

           OSSL_FOOerr(OSSL_FOO_F_SOMETHING, OSSL_FOO_R_WHATEVER);

   With this change, we claim the namespaces OSSL and OPENSSL in a manner
   that can be encoded in C.  For the foreseeable future, this will only
   affect new modules.

   *Richard Levitte and Tim Hudson*

 * Removed BSD cryptodev engine.

   *Rich Salz*

 * Add a build target 'build_all_generated', to build all generated files
   and only that.  This can be used to prepare everything that requires
   things like perl for a system that lacks perl and then move everything
   to that system and do the rest of the build there.

   *Richard Levitte*

 * In the UI interface, make it possible to duplicate the user data.  This
   can be used by engines that need to retain the data for a longer time
   than just the call where this user data is passed.

   *Richard Levitte*

 * Ignore the '-named_curve auto' value for compatibility of applications
   with OpenSSL 1.0.2.

   *Tomáš Mráz <tmraz@fedoraproject.org>*

 * Fragmented SSL/TLS alerts are no longer accepted. An alert message is 2
   bytes long. In theory it is permissible in SSLv3 - TLSv1.2 to fragment such
   alerts across multiple records (some of which could be empty). In practice
   it make no sense to send an empty alert record, or to fragment one. TLSv1.3
   prohibits this altogether and other libraries (BoringSSL, NSS) do not
   support this at all. Supporting it adds significant complexity to the
   record layer, and its removal is unlikely to cause interoperability
   issues.

   *Matt Caswell*

 * Add the ASN.1 types INT32, UINT32, INT64, UINT64 and variants prefixed
   with Z.  These are meant to replace LONG and ZLONG and to be size safe.
   The use of LONG and ZLONG is discouraged and scheduled for deprecation
   in OpenSSL 1.2.0.

   *Richard Levitte*

 * Add the 'z' and 'j' modifiers to BIO_printf() et al formatting string,
   'z' is to be used for [s]size_t, and 'j' - with [u]int64_t.

   *Richard Levitte, Andy Polyakov*

 * Add EC_KEY_get0_engine(), which does for EC_KEY what RSA_get0_engine()
   does for RSA, etc.

   *Richard Levitte*

 * Have 'config' recognise 64-bit mingw and choose 'mingw64' as the target
   platform rather than 'mingw'.

   *Richard Levitte*

 * The functions X509_STORE_add_cert and X509_STORE_add_crl return
   success if they are asked to add an object which already exists
   in the store. This change cascades to other functions which load
   certificates and CRLs.

   *Paul Dale*

 * x86_64 assembly pack: annotate code with DWARF CFI directives to
   facilitate stack unwinding even from assembly subroutines.

   *Andy Polyakov*

 * Remove VAX C specific definitions of OPENSSL_EXPORT, OPENSSL_EXTERN.
   Also remove OPENSSL_GLOBAL entirely, as it became a no-op.

   *Richard Levitte*

 * Remove the VMS-specific reimplementation of gmtime from crypto/o_times.c.
   VMS C's RTL has a fully up to date gmtime() and gmtime_r() since V7.1,
   which is the minimum version we support.

   *Richard Levitte*

 * Certificate time validation (X509_cmp_time) enforces stricter
   compliance with RFC 5280. Fractional seconds and timezone offsets
   are no longer allowed.

   *Emilia Käsper*

 * Add support for ARIA

   *Paul Dale*

 * s_client will now send the Server Name Indication (SNI) extension by
   default unless the new "-noservername" option is used. The server name is
   based on the host provided to the "-connect" option unless overridden by
   using "-servername".

   *Matt Caswell*

 * Add support for SipHash

   *Todd Short*

 * OpenSSL now fails if it receives an unrecognised record type in TLS1.0
   or TLS1.1. Previously this only happened in SSLv3 and TLS1.2. This is to
   prevent issues where no progress is being made and the peer continually
   sends unrecognised record types, using up resources processing them.

   *Matt Caswell*

 * 'openssl passwd' can now produce SHA256 and SHA512 based output,
   using the algorithm defined in
   <https://www.akkadia.org/drepper/SHA-crypt.txt>

   *Richard Levitte*

 * Heartbeat support has been removed; the ABI is changed for now.

   *Richard Levitte, Rich Salz*

 * Support for SSL_OP_NO_ENCRYPT_THEN_MAC in SSL_CONF_cmd.

   *Emilia Käsper*

 * The RSA "null" method, which was partially supported to avoid patent
   issues, has been replaced to always returns NULL.

   *Rich Salz*

OpenSSL 1.1.0
-------------

### Changes between 1.1.0k and 1.1.0l [10 Sep 2019]

 * For built-in EC curves, ensure an EC_GROUP built from the curve name is
   used even when parsing explicit parameters, when loading a encoded key
   or calling `EC_GROUP_new_from_ecpkparameters()`/
   `EC_GROUP_new_from_ecparameters()`.
   This prevents bypass of security hardening and performance gains,
   especially for curves with specialized EC_METHODs.
   By default, if a key encoded with explicit parameters is loaded and later
   encoded, the output is still encoded with explicit parameters, even if
   internally a "named" EC_GROUP is used for computation.

   *Nicola Tuveri*

 * Compute ECC cofactors if not provided during EC_GROUP construction. Before
   this change, EC_GROUP_set_generator would accept order and/or cofactor as
   NULL. After this change, only the cofactor parameter can be NULL. It also
   does some minimal sanity checks on the passed order.
   ([CVE-2019-1547])

   *Billy Bob Brumley*

 * Fixed a padding oracle in PKCS7_dataDecode and CMS_decrypt_set1_pkey.
   An attack is simple, if the first CMS_recipientInfo is valid but the
   second CMS_recipientInfo is chosen ciphertext. If the second
   recipientInfo decodes to PKCS #1 v1.5 form plaintext, the correct
   encryption key will be replaced by garbage, and the message cannot be
   decoded, but if the RSA decryption fails, the correct encryption key is
   used and the recipient will not notice the attack.
   As a work around for this potential attack the length of the decrypted
   key must be equal to the cipher default key length, in case the
   certificate is not given and all recipientInfo are tried out.
   The old behaviour can be re-enabled in the CMS code by setting the
   CMS_DEBUG_DECRYPT flag.
   ([CVE-2019-1563])

   *Bernd Edlinger*

 * Use Windows installation paths in the mingw builds

   Mingw isn't a POSIX environment per se, which means that Windows
   paths should be used for installation.
   ([CVE-2019-1552])

   *Richard Levitte*

### Changes between 1.1.0j and 1.1.0k [28 May 2019]

 * Change the default RSA, DSA and DH size to 2048 bit instead of 1024.
   This changes the size when using the `genpkey` command when no size is given.
   It fixes an omission in earlier changes that changed all RSA, DSA and DH
   generation commands to use 2048 bits by default.

   *Kurt Roeckx*

 * Prevent over long nonces in ChaCha20-Poly1305.

   ChaCha20-Poly1305 is an AEAD cipher, and requires a unique nonce input
   for every encryption operation. RFC 7539 specifies that the nonce value
   (IV) should be 96 bits (12 bytes). OpenSSL allows a variable nonce length
   and front pads the nonce with 0 bytes if it is less than 12
   bytes. However it also incorrectly allows a nonce to be set of up to 16
   bytes. In this case only the last 12 bytes are significant and any
   additional leading bytes are ignored.

   It is a requirement of using this cipher that nonce values are
   unique. Messages encrypted using a reused nonce value are susceptible to
   serious confidentiality and integrity attacks. If an application changes
   the default nonce length to be longer than 12 bytes and then makes a
   change to the leading bytes of the nonce expecting the new value to be a
   new unique nonce then such an application could inadvertently encrypt
   messages with a reused nonce.

   Additionally the ignored bytes in a long nonce are not covered by the
   integrity guarantee of this cipher. Any application that relies on the
   integrity of these ignored leading bytes of a long nonce may be further
   affected. Any OpenSSL internal use of this cipher, including in SSL/TLS,
   is safe because no such use sets such a long nonce value. However user
   applications that use this cipher directly and set a non-default nonce
   length to be longer than 12 bytes may be vulnerable.

   This issue was reported to OpenSSL on 16th of March 2019 by Joran Dirk
   Greef of Ronomon.
   ([CVE-2019-1543])

   *Matt Caswell*

 * Added SCA hardening for modular field inversion in EC_GROUP through
   a new dedicated field_inv() pointer in EC_METHOD.
   This also addresses a leakage affecting conversions from projective
   to affine coordinates.

   *Billy Bob Brumley, Nicola Tuveri*

 * Fix a use after free bug in d2i_X509_PUBKEY when overwriting a
   re-used X509_PUBKEY object if the second PUBKEY is malformed.

   *Bernd Edlinger*

 * Move strictness check from EVP_PKEY_asn1_new() to EVP_PKEY_asn1_add0().

   *Richard Levitte*

 * Remove the 'dist' target and add a tarball building script.  The
   'dist' target has fallen out of use, and it shouldn't be
   necessary to configure just to create a source distribution.

   *Richard Levitte*

### Changes between 1.1.0i and 1.1.0j [20 Nov 2018]

 * Timing vulnerability in DSA signature generation

   The OpenSSL DSA signature algorithm has been shown to be vulnerable to a
   timing side channel attack. An attacker could use variations in the signing
   algorithm to recover the private key.

   This issue was reported to OpenSSL on 16th October 2018 by Samuel Weiser.
   ([CVE-2018-0734])

   *Paul Dale*

 * Timing vulnerability in ECDSA signature generation

   The OpenSSL ECDSA signature algorithm has been shown to be vulnerable to a
   timing side channel attack. An attacker could use variations in the signing
   algorithm to recover the private key.

   This issue was reported to OpenSSL on 25th October 2018 by Samuel Weiser.
   ([CVE-2018-0735])

   *Paul Dale*

 * Add coordinate blinding for EC_POINT and implement projective
   coordinate blinding for generic prime curves as a countermeasure to
   chosen point SCA attacks.

   *Sohaib ul Hassan, Nicola Tuveri, Billy Bob Brumley*

### Changes between 1.1.0h and 1.1.0i [14 Aug 2018]

 * Client DoS due to large DH parameter

   During key agreement in a TLS handshake using a DH(E) based ciphersuite a
   malicious server can send a very large prime value to the client. This will
   cause the client to spend an unreasonably long period of time generating a
   key for this prime resulting in a hang until the client has finished. This
   could be exploited in a Denial Of Service attack.

   This issue was reported to OpenSSL on 5th June 2018 by Guido Vranken
   ([CVE-2018-0732])

   *Guido Vranken*

 * Cache timing vulnerability in RSA Key Generation

   The OpenSSL RSA Key generation algorithm has been shown to be vulnerable to
   a cache timing side channel attack. An attacker with sufficient access to
   mount cache timing attacks during the RSA key generation process could
   recover the private key.

   This issue was reported to OpenSSL on 4th April 2018 by Alejandro Cabrera
   Aldaya, Billy Brumley, Cesar Pereida Garcia and Luis Manuel Alvarez Tapia.
   ([CVE-2018-0737])

   *Billy Brumley*

 * Make EVP_PKEY_asn1_new() a bit stricter about its input.  A NULL pem_str
   parameter is no longer accepted, as it leads to a corrupt table.  NULL
   pem_str is reserved for alias entries only.

   *Richard Levitte*

 * Revert blinding in ECDSA sign and instead make problematic addition
   length-invariant. Switch even to fixed-length Montgomery multiplication.

   *Andy Polyakov*

 * Change generating and checking of primes so that the error rate of not
   being prime depends on the intended use based on the size of the input.
   For larger primes this will result in more rounds of Miller-Rabin.
   The maximal error rate for primes with more than 1080 bits is lowered
   to 2^-128.

   *Kurt Roeckx, Annie Yousar*

 * Increase the number of Miller-Rabin rounds for DSA key generating to 64.

   *Kurt Roeckx*

 * Add blinding to ECDSA and DSA signatures to protect against side channel
   attacks discovered by Keegan Ryan (NCC Group).

   *Matt Caswell*

 * When unlocking a pass phrase protected PEM file or PKCS#8 container, we
   now allow empty (zero character) pass phrases.

   *Richard Levitte*

 * Certificate time validation (X509_cmp_time) enforces stricter
   compliance with RFC 5280. Fractional seconds and timezone offsets
   are no longer allowed.

   *Emilia Käsper*

 * Fixed a text canonicalisation bug in CMS

   Where a CMS detached signature is used with text content the text goes
   through a canonicalisation process first prior to signing or verifying a
   signature. This process strips trailing space at the end of lines, converts
   line terminators to CRLF and removes additional trailing line terminators
   at the end of a file. A bug in the canonicalisation process meant that
   some characters, such as form-feed, were incorrectly treated as whitespace
   and removed. This is contrary to the specification (RFC5485). This fix
   could mean that detached text data signed with an earlier version of
   OpenSSL 1.1.0 may fail to verify using the fixed version, or text data
   signed with a fixed OpenSSL may fail to verify with an earlier version of
   OpenSSL 1.1.0. A workaround is to only verify the canonicalised text data
   and use the "-binary" flag (for the "cms" command line application) or set
   the SMIME_BINARY/PKCS7_BINARY/CMS_BINARY flags (if using CMS_verify()).

   *Matt Caswell*

### Changes between 1.1.0g and 1.1.0h [27 Mar 2018]

 * Constructed ASN.1 types with a recursive definition could exceed the stack

   Constructed ASN.1 types with a recursive definition (such as can be found
   in PKCS7) could eventually exceed the stack given malicious input with
   excessive recursion. This could result in a Denial Of Service attack. There
   are no such structures used within SSL/TLS that come from untrusted sources
   so this is considered safe.

   This issue was reported to OpenSSL on 4th January 2018 by the OSS-fuzz
   project.
   ([CVE-2018-0739])

   *Matt Caswell*

 * Incorrect CRYPTO_memcmp on HP-UX PA-RISC

   Because of an implementation bug the PA-RISC CRYPTO_memcmp function is
   effectively reduced to only comparing the least significant bit of each
   byte. This allows an attacker to forge messages that would be considered as
   authenticated in an amount of tries lower than that guaranteed by the
   security claims of the scheme. The module can only be compiled by the
   HP-UX assembler, so that only HP-UX PA-RISC targets are affected.

   This issue was reported to OpenSSL on 2nd March 2018 by Peter Waltenberg
   (IBM).
   ([CVE-2018-0733])

   *Andy Polyakov*

 * Add a build target 'build_all_generated', to build all generated files
   and only that.  This can be used to prepare everything that requires
   things like perl for a system that lacks perl and then move everything
   to that system and do the rest of the build there.

   *Richard Levitte*

 * Backport SSL_OP_NO_RENGOTIATION

   OpenSSL 1.0.2 and below had the ability to disable renegotiation using the
   (undocumented) SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS flag. Due to the opacity
   changes this is no longer possible in 1.1.0. Therefore, the new
   SSL_OP_NO_RENEGOTIATION option from 1.1.1-dev has been backported to
   1.1.0 to provide equivalent functionality.

   Note that if an application built against 1.1.0h headers (or above) is run
   using an older version of 1.1.0 (prior to 1.1.0h) then the option will be
   accepted but nothing will happen, i.e. renegotiation will not be prevented.

   *Matt Caswell*

 * Removed the OS390-Unix config target.  It relied on a script that doesn't
   exist.

   *Rich Salz*

 * rsaz_1024_mul_avx2 overflow bug on x86_64

   There is an overflow bug in the AVX2 Montgomery multiplication procedure
   used in exponentiation with 1024-bit moduli. No EC algorithms are affected.
   Analysis suggests that attacks against RSA and DSA as a result of this
   defect would be very difficult to perform and are not believed likely.
   Attacks against DH1024 are considered just feasible, because most of the
   work necessary to deduce information about a private key may be performed
   offline. The amount of resources required for such an attack would be
   significant. However, for an attack on TLS to be meaningful, the server
   would have to share the DH1024 private key among multiple clients, which is
   no longer an option since CVE-2016-0701.

   This only affects processors that support the AVX2 but not ADX extensions
   like Intel Haswell (4th generation).

   This issue was reported to OpenSSL by David Benjamin (Google). The issue
   was originally found via the OSS-Fuzz project.
   ([CVE-2017-3738])

   *Andy Polyakov*

### Changes between 1.1.0f and 1.1.0g [2 Nov 2017]

 * bn_sqrx8x_internal carry bug on x86_64

   There is a carry propagating bug in the x86_64 Montgomery squaring
   procedure. No EC algorithms are affected. Analysis suggests that attacks
   against RSA and DSA as a result of this defect would be very difficult to
   perform and are not believed likely. Attacks against DH are considered just
   feasible (although very difficult) because most of the work necessary to
   deduce information about a private key may be performed offline. The amount
   of resources required for such an attack would be very significant and
   likely only accessible to a limited number of attackers. An attacker would
   additionally need online access to an unpatched system using the target
   private key in a scenario with persistent DH parameters and a private
   key that is shared between multiple clients.

   This only affects processors that support the BMI1, BMI2 and ADX extensions
   like Intel Broadwell (5th generation) and later or AMD Ryzen.

   This issue was reported to OpenSSL by the OSS-Fuzz project.
   ([CVE-2017-3736])

   *Andy Polyakov*

 * Malformed X.509 IPAddressFamily could cause OOB read

   If an X.509 certificate has a malformed IPAddressFamily extension,
   OpenSSL could do a one-byte buffer overread. The most likely result
   would be an erroneous display of the certificate in text format.

   This issue was reported to OpenSSL by the OSS-Fuzz project.
   ([CVE-2017-3735])

   *Rich Salz*

### Changes between 1.1.0e and 1.1.0f [25 May 2017]

 * Have 'config' recognise 64-bit mingw and choose 'mingw64' as the target
   platform rather than 'mingw'.

   *Richard Levitte*

 * Remove the VMS-specific reimplementation of gmtime from crypto/o_times.c.
   VMS C's RTL has a fully up to date gmtime() and gmtime_r() since V7.1,
   which is the minimum version we support.

   *Richard Levitte*

### Changes between 1.1.0d and 1.1.0e [16 Feb 2017]

 * Encrypt-Then-Mac renegotiation crash

   During a renegotiation handshake if the Encrypt-Then-Mac extension is
   negotiated where it was not in the original handshake (or vice-versa) then
   this can cause OpenSSL to crash (dependent on ciphersuite). Both clients
   and servers are affected.

   This issue was reported to OpenSSL by Joe Orton (Red Hat).
   ([CVE-2017-3733])

   *Matt Caswell*

### Changes between 1.1.0c and 1.1.0d [26 Jan 2017]

 * Truncated packet could crash via OOB read

   If one side of an SSL/TLS path is running on a 32-bit host and a specific
   cipher is being used, then a truncated packet can cause that host to
   perform an out-of-bounds read, usually resulting in a crash.

   This issue was reported to OpenSSL by Robert Święcki of Google.
   ([CVE-2017-3731])

   *Andy Polyakov*

 * Bad (EC)DHE parameters cause a client crash

   If a malicious server supplies bad parameters for a DHE or ECDHE key
   exchange then this can result in the client attempting to dereference a
   NULL pointer leading to a client crash. This could be exploited in a Denial
   of Service attack.

   This issue was reported to OpenSSL by Guido Vranken.
   ([CVE-2017-3730])

   *Matt Caswell*

 * BN_mod_exp may produce incorrect results on x86_64

   There is a carry propagating bug in the x86_64 Montgomery squaring
   procedure. No EC algorithms are affected. Analysis suggests that attacks
   against RSA and DSA as a result of this defect would be very difficult to
   perform and are not believed likely. Attacks against DH are considered just
   feasible (although very difficult) because most of the work necessary to
   deduce information about a private key may be performed offline. The amount
   of resources required for such an attack would be very significant and
   likely only accessible to a limited number of attackers. An attacker would
   additionally need online access to an unpatched system using the target
   private key in a scenario with persistent DH parameters and a private
   key that is shared between multiple clients. For example this can occur by
   default in OpenSSL DHE based SSL/TLS ciphersuites. Note: This issue is very
   similar to CVE-2015-3193 but must be treated as a separate problem.

   This issue was reported to OpenSSL by the OSS-Fuzz project.
   ([CVE-2017-3732])

   *Andy Polyakov*

### Changes between 1.1.0b and 1.1.0c [10 Nov 2016]

 * ChaCha20/Poly1305 heap-buffer-overflow

   TLS connections using `*-CHACHA20-POLY1305` ciphersuites are susceptible to
   a DoS attack by corrupting larger payloads. This can result in an OpenSSL
   crash. This issue is not considered to be exploitable beyond a DoS.

   This issue was reported to OpenSSL by Robert Święcki (Google Security Team)
   ([CVE-2016-7054])

   *Richard Levitte*

 * CMS Null dereference

   Applications parsing invalid CMS structures can crash with a NULL pointer
   dereference. This is caused by a bug in the handling of the ASN.1 CHOICE
   type in OpenSSL 1.1.0 which can result in a NULL value being passed to the
   structure callback if an attempt is made to free certain invalid encodings.
   Only CHOICE structures using a callback which do not handle NULL value are
   affected.

   This issue was reported to OpenSSL by Tyler Nighswander of ForAllSecure.
   ([CVE-2016-7053])

   *Stephen Henson*

 * Montgomery multiplication may produce incorrect results

   There is a carry propagating bug in the Broadwell-specific Montgomery
   multiplication procedure that handles input lengths divisible by, but
   longer than 256 bits. Analysis suggests that attacks against RSA, DSA
   and DH private keys are impossible. This is because the subroutine in
   question is not used in operations with the private key itself and an input
   of the attacker's direct choice. Otherwise the bug can manifest itself as
   transient authentication and key negotiation failures or reproducible
   erroneous outcome of public-key operations with specially crafted input.
   Among EC algorithms only Brainpool P-512 curves are affected and one
   presumably can attack ECDH key negotiation. Impact was not analyzed in
   detail, because pre-requisites for attack are considered unlikely. Namely
   multiple clients have to choose the curve in question and the server has to
   share the private key among them, neither of which is default behaviour.
   Even then only clients that chose the curve will be affected.

   This issue was publicly reported as transient failures and was not
   initially recognized as a security issue. Thanks to Richard Morgan for
   providing reproducible case.
   ([CVE-2016-7055])

   *Andy Polyakov*

 * Removed automatic addition of RPATH in shared libraries and executables,
   as this was a remainder from OpenSSL 1.0.x and isn't needed any more.

   *Richard Levitte*

### Changes between 1.1.0a and 1.1.0b [26 Sep 2016]

 * Fix Use After Free for large message sizes

   The patch applied to address CVE-2016-6307 resulted in an issue where if a
   message larger than approx 16k is received then the underlying buffer to
   store the incoming message is reallocated and moved. Unfortunately a
   dangling pointer to the old location is left which results in an attempt to
   write to the previously freed location. This is likely to result in a
   crash, however it could potentially lead to execution of arbitrary code.

   This issue only affects OpenSSL 1.1.0a.

   This issue was reported to OpenSSL by Robert Święcki.
   ([CVE-2016-6309])

   *Matt Caswell*

### Changes between 1.1.0 and 1.1.0a [22 Sep 2016]

 * OCSP Status Request extension unbounded memory growth

   A malicious client can send an excessively large OCSP Status Request
   extension. If that client continually requests renegotiation, sending a
   large OCSP Status Request extension each time, then there will be unbounded
   memory growth on the server. This will eventually lead to a Denial Of
   Service attack through memory exhaustion. Servers with a default
   configuration are vulnerable even if they do not support OCSP. Builds using
   the "no-ocsp" build time option are not affected.

   This issue was reported to OpenSSL by Shi Lei (Gear Team, Qihoo 360 Inc.)
   ([CVE-2016-6304])

   *Matt Caswell*

 * SSL_peek() hang on empty record

   OpenSSL 1.1.0 SSL/TLS will hang during a call to SSL_peek() if the peer
   sends an empty record. This could be exploited by a malicious peer in a
   Denial Of Service attack.

   This issue was reported to OpenSSL by Alex Gaynor.
   ([CVE-2016-6305])

   *Matt Caswell*

 * Excessive allocation of memory in tls_get_message_header() and
   dtls1_preprocess_fragment()

   A (D)TLS message includes 3 bytes for its length in the header for the
   message. This would allow for messages up to 16Mb in length. Messages of
   this length are excessive and OpenSSL includes a check to ensure that a
   peer is sending reasonably sized messages in order to avoid too much memory
   being consumed to service a connection. A flaw in the logic of version
   1.1.0 means that memory for the message is allocated too early, prior to
   the excessive message length check. Due to way memory is allocated in
   OpenSSL this could mean an attacker could force up to 21Mb to be allocated
   to service a connection. This could lead to a Denial of Service through
   memory exhaustion. However, the excessive message length check still takes
   place, and this would cause the connection to immediately fail. Assuming
   that the application calls SSL_free() on the failed connection in a timely
   manner then the 21Mb of allocated memory will then be immediately freed
   again. Therefore, the excessive memory allocation will be transitory in
   nature. This then means that there is only a security impact if:

   1) The application does not call SSL_free() in a timely manner in the event
   that the connection fails
   or
   2) The application is working in a constrained environment where there is
   very little free memory
   or
   3) The attacker initiates multiple connection attempts such that there are
   multiple connections in a state where memory has been allocated for the
   connection; SSL_free() has not yet been called; and there is insufficient
   memory to service the multiple requests.

   Except in the instance of (1) above any Denial Of Service is likely to be
   transitory because as soon as the connection fails the memory is
   subsequently freed again in the SSL_free() call. However there is an
   increased risk during this period of application crashes due to the lack of
   memory - which would then mean a more serious Denial of Service.

   This issue was reported to OpenSSL by Shi Lei (Gear Team, Qihoo 360 Inc.)
   (CVE-2016-6307 and CVE-2016-6308)

   *Matt Caswell*

 * solaris-x86-cc, i.e. 32-bit configuration with vendor compiler,
   had to be removed. Primary reason is that vendor assembler can't
   assemble our modules with -KPIC flag. As result it, assembly
   support, was not even available as option. But its lack means
   lack of side-channel resistant code, which is incompatible with
   security by todays standards. Fortunately gcc is readily available
   prepackaged option, which we firmly point at...

   *Andy Polyakov*

### Changes between 1.0.2h and 1.1.0  [25 Aug 2016]

 * Windows command-line tool supports UTF-8 opt-in option for arguments
   and console input. Setting OPENSSL_WIN32_UTF8 environment variable
   (to any value) allows Windows user to access PKCS#12 file generated
   with Windows CryptoAPI and protected with non-ASCII password, as well
   as files generated under UTF-8 locale on Linux also protected with
   non-ASCII password.

   *Andy Polyakov*

 * To mitigate the SWEET32 attack ([CVE-2016-2183]), 3DES cipher suites
   have been disabled by default and removed from DEFAULT, just like RC4.
   See the RC4 item below to re-enable both.

   *Rich Salz*

 * The method for finding the storage location for the Windows RAND seed file
   has changed. First we check %RANDFILE%. If that is not set then we check
   the directories %HOME%, %USERPROFILE% and %SYSTEMROOT% in that order. If
   all else fails we fall back to C:\.

   *Matt Caswell*

 * The EVP_EncryptUpdate() function has had its return type changed from void
   to int. A return of 0 indicates and error while a return of 1 indicates
   success.

   *Matt Caswell*

 * The flags RSA_FLAG_NO_CONSTTIME, DSA_FLAG_NO_EXP_CONSTTIME and
   DH_FLAG_NO_EXP_CONSTTIME which previously provided the ability to switch
   off the constant time implementation for RSA, DSA and DH have been made
   no-ops and deprecated.

   *Matt Caswell*

 * Windows RAND implementation was simplified to only get entropy by
   calling CryptGenRandom(). Various other RAND-related tickets
   were also closed.

   *Joseph Wylie Yandle, Rich Salz*

 * The stack and lhash API's were renamed to start with `OPENSSL_SK_`
   and `OPENSSL_LH_`, respectively.  The old names are available
   with API compatibility.  They new names are now completely documented.

   *Rich Salz*

 * Unify TYPE_up_ref(obj) methods signature.
   SSL_CTX_up_ref(), SSL_up_ref(), X509_up_ref(), EVP_PKEY_up_ref(),
   X509_CRL_up_ref(), X509_OBJECT_up_ref_count() methods are now returning an
   int (instead of void) like all others TYPE_up_ref() methods.
   So now these methods also check the return value of CRYPTO_atomic_add(),
   and the validity of object reference counter.

   *fdasilvayy@gmail.com*

 * With Windows Visual Studio builds, the .pdb files are installed
   alongside the installed libraries and executables.  For a static
   library installation, ossl_static.pdb is the associate compiler
   generated .pdb file to be used when linking programs.

   *Richard Levitte*

 * Remove openssl.spec.  Packaging files belong with the packagers.

   *Richard Levitte*

 * Automatic Darwin/OSX configuration has had a refresh, it will now
   recognise x86_64 architectures automatically.  You can still decide
   to build for a different bitness with the environment variable
   KERNEL_BITS (can be 32 or 64), for example:

           KERNEL_BITS=32 ./config

   *Richard Levitte*

 * Change default algorithms in pkcs8 utility to use PKCS#5 v2.0,
   256 bit AES and HMAC with SHA256.

   *Steve Henson*

 * Remove support for MIPS o32 ABI on IRIX (and IRIX only).

   *Andy Polyakov*

 * Triple-DES ciphers have been moved from HIGH to MEDIUM.

   *Rich Salz*

 * To enable users to have their own config files and build file templates,
   Configure looks in the directory indicated by the environment variable
   OPENSSL_LOCAL_CONFIG_DIR as well as the in-source Configurations/
   directory.  On VMS, OPENSSL_LOCAL_CONFIG_DIR is expected to be a logical
   name and is used as is.

   *Richard Levitte*

 * The following datatypes were made opaque: X509_OBJECT, X509_STORE_CTX,
   X509_STORE, X509_LOOKUP, and X509_LOOKUP_METHOD.  The unused type
   X509_CERT_FILE_CTX was removed.

   *Rich Salz*

 * "shared" builds are now the default. To create only static libraries use
   the "no-shared" Configure option.

   *Matt Caswell*

 * Remove the no-aes, no-hmac, no-rsa, no-sha and no-md5 Configure options.
   All of these option have not worked for some while and are fundamental
   algorithms.

   *Matt Caswell*

 * Make various cleanup routines no-ops and mark them as deprecated. Most
   global cleanup functions are no longer required because they are handled
   via auto-deinit (see OPENSSL_init_crypto and OPENSSL_init_ssl man pages).
   Explicitly de-initing can cause problems (e.g. where a library that uses
   OpenSSL de-inits, but an application is still using it). The affected
   functions are CONF_modules_free(), ENGINE_cleanup(), OBJ_cleanup(),
   EVP_cleanup(), BIO_sock_cleanup(), CRYPTO_cleanup_all_ex_data(),
   RAND_cleanup(), SSL_COMP_free_compression_methods(), ERR_free_strings() and
   COMP_zlib_cleanup().

   *Matt Caswell*

 * --strict-warnings no longer enables runtime debugging options
   such as REF_DEBUG. Instead, debug options are automatically
   enabled with '--debug' builds.

   *Andy Polyakov, Emilia Käsper*

 * Made DH and DH_METHOD opaque. The structures for managing DH objects
   have been moved out of the public header files. New functions for managing
   these have been added.

   *Matt Caswell*

 * Made RSA and RSA_METHOD opaque. The structures for managing RSA
   objects have been moved out of the public header files. New
   functions for managing these have been added.

   *Richard Levitte*

 * Made DSA and DSA_METHOD opaque. The structures for managing DSA objects
   have been moved out of the public header files. New functions for managing
   these have been added.

   *Matt Caswell*

 * Made BIO and BIO_METHOD opaque. The structures for managing BIOs have been
   moved out of the public header files. New functions for managing these
   have been added.

   *Matt Caswell*

 * Removed no-rijndael as a config option. Rijndael is an old name for AES.

   *Matt Caswell*

 * Removed the mk1mf build scripts.

   *Richard Levitte*

 * Headers are now wrapped, if necessary, with OPENSSL_NO_xxx, so
   it is always safe to #include a header now.

   *Rich Salz*

 * Removed the aged BC-32 config and all its supporting scripts

   *Richard Levitte*

 * Removed support for Ultrix, Netware, and OS/2.

   *Rich Salz*

 * Add support for HKDF.

   *Alessandro Ghedini*

 * Add support for blake2b and blake2s

   *Bill Cox*

 * Added support for "pipelining". Ciphers that have the
   EVP_CIPH_FLAG_PIPELINE flag set have a capability to process multiple
   encryptions/decryptions simultaneously. There are currently no built-in
   ciphers with this property but the expectation is that engines will be able
   to offer it to significantly improve throughput. Support has been extended
   into libssl so that multiple records for a single connection can be
   processed in one go (for >=TLS 1.1).

   *Matt Caswell*

 * Added the AFALG engine. This is an async capable engine which is able to
   offload work to the Linux kernel. In this initial version it only supports
   AES128-CBC. The kernel must be version 4.1.0 or greater.

   *Catriona Lucey*

 * OpenSSL now uses a new threading API. It is no longer necessary to
   set locking callbacks to use OpenSSL in a multi-threaded environment. There
   are two supported threading models: pthreads and windows threads. It is
   also possible to configure OpenSSL at compile time for "no-threads". The
   old threading API should no longer be used. The functions have been
   replaced with "no-op" compatibility macros.

   *Alessandro Ghedini, Matt Caswell*

 * Modify behavior of ALPN to invoke callback after SNI/servername
   callback, such that updates to the SSL_CTX affect ALPN.

   *Todd Short*

 * Add SSL_CIPHER queries for authentication and key-exchange.

   *Todd Short*

 * Changes to the DEFAULT cipherlist:
   - Prefer (EC)DHE handshakes over plain RSA.
   - Prefer AEAD ciphers over legacy ciphers.
   - Prefer ECDSA over RSA when both certificates are available.
   - Prefer TLSv1.2 ciphers/PRF.
   - Remove DSS, SEED, IDEA, CAMELLIA, and AES-CCM from the
     default cipherlist.

   *Emilia Käsper*

 * Change the ECC default curve list to be this, in order: x25519,
   secp256r1, secp521r1, secp384r1.

   *Rich Salz*

 * RC4 based libssl ciphersuites are now classed as "weak" ciphers and are
   disabled by default. They can be re-enabled using the
   enable-weak-ssl-ciphers option to Configure.

   *Matt Caswell*

 * If the server has ALPN configured, but supports no protocols that the
   client advertises, send a fatal "no_application_protocol" alert.
   This behaviour is SHALL in RFC 7301, though it isn't universally
   implemented by other servers.

   *Emilia Käsper*

 * Add X25519 support.
   Add ASN.1 and EVP_PKEY methods for X25519. This includes support
   for public and private key encoding using the format documented in
   draft-ietf-curdle-pkix-02. The corresponding EVP_PKEY method supports
   key generation and key derivation.

   TLS support complies with draft-ietf-tls-rfc4492bis-08 and uses
   X25519(29).

   *Steve Henson*

 * Deprecate SRP_VBASE_get_by_user.
   SRP_VBASE_get_by_user had inconsistent memory management behaviour.
   In order to fix an unavoidable memory leak ([CVE-2016-0798]),
   SRP_VBASE_get_by_user was changed to ignore the "fake user" SRP
   seed, even if the seed is configured.

   Users should use SRP_VBASE_get1_by_user instead. Note that in
   SRP_VBASE_get1_by_user, caller must free the returned value. Note
   also that even though configuring the SRP seed attempts to hide
   invalid usernames by continuing the handshake with fake
   credentials, this behaviour is not constant time and no strong
   guarantees are made that the handshake is indistinguishable from
   that of a valid user.

   *Emilia Käsper*

 * Configuration change; it's now possible to build dynamic engines
   without having to build shared libraries and vice versa.  This
   only applies to the engines in `engines/`, those in `crypto/engine/`
   will always be built into libcrypto (i.e. "static").

   Building dynamic engines is enabled by default; to disable, use
   the configuration option "disable-dynamic-engine".

   The only requirements for building dynamic engines are the
   presence of the DSO module and building with position independent
   code, so they will also automatically be disabled if configuring
   with "disable-dso" or "disable-pic".

   The macros OPENSSL_NO_STATIC_ENGINE and OPENSSL_NO_DYNAMIC_ENGINE
   are also taken away from openssl/opensslconf.h, as they are
   irrelevant.

   *Richard Levitte*

 * Configuration change; if there is a known flag to compile
   position independent code, it will always be applied on the
   libcrypto and libssl object files, and never on the application
   object files.  This means other libraries that use routines from
   libcrypto / libssl can be made into shared libraries regardless
   of how OpenSSL was configured.

   If this isn't desirable, the configuration options "disable-pic"
   or "no-pic" can be used to disable the use of PIC.  This will
   also disable building shared libraries and dynamic engines.

   *Richard Levitte*

 * Removed JPAKE code.  It was experimental and has no wide use.

   *Rich Salz*

 * The INSTALL_PREFIX Makefile variable has been renamed to
   DESTDIR.  That makes for less confusion on what this variable
   is for.  Also, the configuration option --install_prefix is
   removed.

   *Richard Levitte*

 * Heartbeat for TLS has been removed and is disabled by default
   for DTLS; configure with enable-heartbeats.  Code that uses the
   old #define's might need to be updated.

   *Emilia Käsper, Rich Salz*

 * Rename REF_CHECK to REF_DEBUG.

   *Rich Salz*

 * New "unified" build system

   The "unified" build system is aimed to be a common system for all
   platforms we support.  With it comes new support for VMS.

   This system builds supports building in a different directory tree
   than the source tree.  It produces one Makefile (for unix family
   or lookalikes), or one descrip.mms (for VMS).

   The source of information to make the Makefile / descrip.mms is
   small files called 'build.info', holding the necessary
   information for each directory with source to compile, and a
   template in Configurations, like unix-Makefile.tmpl or
   descrip.mms.tmpl.

   With this change, the library names were also renamed on Windows
   and on VMS.  They now have names that are closer to the standard
   on Unix, and include the major version number, and in certain
   cases, the architecture they are built for.  See "Notes on shared
   libraries" in INSTALL.

   We rely heavily on the perl module Text::Template.

   *Richard Levitte*

 * Added support for auto-initialisation and de-initialisation of the library.
   OpenSSL no longer requires explicit init or deinit routines to be called,
   except in certain circumstances. See the OPENSSL_init_crypto() and
   OPENSSL_init_ssl() man pages for further information.

   *Matt Caswell*

 * The arguments to the DTLSv1_listen function have changed. Specifically the
   "peer" argument is now expected to be a BIO_ADDR object.

 * Rewrite of BIO networking library. The BIO library lacked consistent
   support of IPv6, and adding it required some more extensive
   modifications.  This introduces the BIO_ADDR and BIO_ADDRINFO types,
   which hold all types of addresses and chains of address information.
   It also introduces a new API, with functions like BIO_socket,
   BIO_connect, BIO_listen, BIO_lookup and a rewrite of BIO_accept.
   The source/sink BIOs BIO_s_connect, BIO_s_accept and BIO_s_datagram
   have been adapted accordingly.

   *Richard Levitte*

 * RSA_padding_check_PKCS1_type_1 now accepts inputs with and without
   the leading 0-byte.

   *Emilia Käsper*

 * CRIME protection: disable compression by default, even if OpenSSL is
   compiled with zlib enabled. Applications can still enable compression
   by calling SSL_CTX_clear_options(ctx, SSL_OP_NO_COMPRESSION), or by
   using the SSL_CONF library to configure compression.

   *Emilia Käsper*

 * The signature of the session callback configured with
   SSL_CTX_sess_set_get_cb was changed. The read-only input buffer
   was explicitly marked as `const unsigned char*` instead of
   `unsigned char*`.

   *Emilia Käsper*

 * Always DPURIFY. Remove the use of uninitialized memory in the
   RNG, and other conditional uses of DPURIFY. This makes -DPURIFY a no-op.

   *Emilia Käsper*

 * Removed many obsolete configuration items, including
      DES_PTR, DES_RISC1, DES_RISC2, DES_INT
      MD2_CHAR, MD2_INT, MD2_LONG
      BF_PTR, BF_PTR2
      IDEA_SHORT, IDEA_LONG
      RC2_SHORT, RC2_LONG, RC4_LONG, RC4_CHUNK, RC4_INDEX

   *Rich Salz, with advice from Andy Polyakov*

 * Many BN internals have been moved to an internal header file.

   *Rich Salz with help from Andy Polyakov*

 * Configuration and writing out the results from it has changed.
   Files such as Makefile include/openssl/opensslconf.h and are now
   produced through general templates, such as Makefile.in and
   crypto/opensslconf.h.in and some help from the perl module
   Text::Template.

   Also, the center of configuration information is no longer
   Makefile.  Instead, Configure produces a perl module in
   configdata.pm which holds most of the config data (in the hash
   table %config), the target data that comes from the target
   configuration in one of the `Configurations/*.conf` files (in
   %target).

   *Richard Levitte*

 * To clarify their intended purposes, the Configure options
   --prefix and --openssldir change their semantics, and become more
   straightforward and less interdependent.

   --prefix shall be used exclusively to give the location INSTALLTOP
   where programs, scripts, libraries, include files and manuals are
   going to be installed.  The default is now /usr/local.

   --openssldir shall be used exclusively to give the default
   location OPENSSLDIR where certificates, private keys, CRLs are
   managed.  This is also where the default openssl.cnf gets
   installed.
   If the directory given with this option is a relative path, the
   values of both the --prefix value and the --openssldir value will
   be combined to become OPENSSLDIR.
   The default for --openssldir is INSTALLTOP/ssl.

   Anyone who uses --openssldir to specify where OpenSSL is to be
   installed MUST change to use --prefix instead.

   *Richard Levitte*

 * The GOST engine was out of date and therefore it has been removed. An up
   to date GOST engine is now being maintained in an external repository.
   See: <https://wiki.openssl.org/index.php/Binaries>. Libssl still retains
   support for GOST ciphersuites (these are only activated if a GOST engine
   is present).

   *Matt Caswell*

 * EGD is no longer supported by default; use enable-egd when
   configuring.

   *Ben Kaduk and Rich Salz*

 * The distribution now has Makefile.in files, which are used to
   create Makefile's when Configure is run.  *Configure must be run
   before trying to build now.*

   *Rich Salz*

 * The return value for SSL_CIPHER_description() for error conditions
   has changed.

   *Rich Salz*

 * Support for RFC6698/RFC7671 DANE TLSA peer authentication.

   Obtaining and performing DNSSEC validation of TLSA records is
   the application's responsibility.  The application provides
   the TLSA records of its choice to OpenSSL, and these are then
   used to authenticate the peer.

   The TLSA records need not even come from DNS.  They can, for
   example, be used to implement local end-entity certificate or
   trust-anchor "pinning", where the "pin" data takes the form
   of TLSA records, which can augment or replace verification
   based on the usual WebPKI public certification authorities.

   *Viktor Dukhovni*

 * Revert default OPENSSL_NO_DEPRECATED setting.  Instead OpenSSL
   continues to support deprecated interfaces in default builds.
   However, applications are strongly advised to compile their
   source files with -DOPENSSL_API_COMPAT=0x10100000L, which hides
   the declarations of all interfaces deprecated in 0.9.8, 1.0.0
   or the 1.1.0 releases.

   In environments in which all applications have been ported to
   not use any deprecated interfaces OpenSSL's Configure script
   should be used with the --api=1.1.0 option to entirely remove
   support for the deprecated features from the library and
   unconditionally disable them in the installed headers.
   Essentially the same effect can be achieved with the "no-deprecated"
   argument to Configure, except that this will always restrict
   the build to just the latest API, rather than a fixed API
   version.

   As applications are ported to future revisions of the API,
   they should update their compile-time OPENSSL_API_COMPAT define
   accordingly, but in most cases should be able to continue to
   compile with later releases.

   The OPENSSL_API_COMPAT versions for 1.0.0, and 0.9.8 are
   0x10000000L and 0x00908000L, respectively.  However those
   versions did not support the OPENSSL_API_COMPAT feature, and
   so applications are not typically tested for explicit support
   of just the undeprecated features of either release.

   *Viktor Dukhovni*

 * Add support for setting the minimum and maximum supported protocol.
   It can bet set via the SSL_set_min_proto_version() and
   SSL_set_max_proto_version(), or via the SSL_CONF's MinProtocol and
   MaxProtocol.  It's recommended to use the new APIs to disable
   protocols instead of disabling individual protocols using
   SSL_set_options() or SSL_CONF's Protocol.  This change also
   removes support for disabling TLS 1.2 in the OpenSSL TLS
   client at compile time by defining OPENSSL_NO_TLS1_2_CLIENT.

   *Kurt Roeckx*

 * Support for ChaCha20 and Poly1305 added to libcrypto and libssl.

   *Andy Polyakov*

 * New EC_KEY_METHOD, this replaces the older ECDSA_METHOD and ECDH_METHOD
   and integrates ECDSA and ECDH functionality into EC. Implementations can
   now redirect key generation and no longer need to convert to or from
   ECDSA_SIG format.

   Note: the ecdsa.h and ecdh.h headers are now no longer needed and just
   include the ec.h header file instead.

   *Steve Henson*

 * Remove support for all 40 and 56 bit ciphers.  This includes all the export
   ciphers who are no longer supported and drops support the ephemeral RSA key
   exchange. The LOW ciphers currently doesn't have any ciphers in it.

   *Kurt Roeckx*

 * Made EVP_MD_CTX, EVP_MD, EVP_CIPHER_CTX, EVP_CIPHER and HMAC_CTX
   opaque.  For HMAC_CTX, the following constructors and destructors
   were added:

       HMAC_CTX *HMAC_CTX_new(void);
       void HMAC_CTX_free(HMAC_CTX *ctx);

   For EVP_MD and EVP_CIPHER, complete APIs to create, fill and
   destroy such methods has been added.  See EVP_MD_meth_new(3) and
   EVP_CIPHER_meth_new(3) for documentation.

   Additional changes:
   1) `EVP_MD_CTX_cleanup()`, `EVP_CIPHER_CTX_cleanup()` and
      `HMAC_CTX_cleanup()` were removed. `HMAC_CTX_reset()` and
      `EVP_MD_CTX_reset()` should be called instead to reinitialise
      an already created structure.
   2) For consistency with the majority of our object creators and
      destructors, `EVP_MD_CTX_(create|destroy)` were renamed to
      `EVP_MD_CTX_(new|free)`.  The old names are retained as macros
      for deprecated builds.

   *Richard Levitte*

 * Added ASYNC support. Libcrypto now includes the async sub-library to enable
   cryptographic operations to be performed asynchronously as long as an
   asynchronous capable engine is used. See the ASYNC_start_job() man page for
   further details. Libssl has also had this capability integrated with the
   introduction of the new mode SSL_MODE_ASYNC and associated error
   SSL_ERROR_WANT_ASYNC. See the SSL_CTX_set_mode() and SSL_get_error() man
   pages. This work was developed in partnership with Intel Corp.

   *Matt Caswell*

 * SSL_{CTX_}set_ecdh_auto() has been removed and ECDH is support is
   always enabled now.  If you want to disable the support you should
   exclude it using the list of supported ciphers. This also means that the
   "-no_ecdhe" option has been removed from s_server.

   *Kurt Roeckx*

 * SSL_{CTX}_set_tmp_ecdh() which can set 1 EC curve now internally calls
   SSL_{CTX_}set1_curves() which can set a list.

   *Kurt Roeckx*

 * Remove support for SSL_{CTX_}set_tmp_ecdh_callback().  You should set the
   curve you want to support using SSL_{CTX_}set1_curves().

   *Kurt Roeckx*

 * State machine rewrite. The state machine code has been significantly
   refactored in order to remove much duplication of code and solve issues
   with the old code (see [ssl/statem/README.md](ssl/statem/README.md) for
   further details). This change does have some associated API changes.
   Notably the SSL_state() function has been removed and replaced by
   SSL_get_state which now returns an "OSSL_HANDSHAKE_STATE" instead of an int.
   SSL_set_state() has been removed altogether. The previous handshake states
   defined in ssl.h and ssl3.h have also been removed.

   *Matt Caswell*

 * All instances of the string "ssleay" in the public API were replaced
   with OpenSSL (case-matching; e.g., OPENSSL_VERSION for #define's)
   Some error codes related to internal RSA_eay API's were renamed.

   *Rich Salz*

 * The demo files in crypto/threads were moved to demo/threads.

   *Rich Salz*

 * Removed obsolete engines: 4758cca, aep, atalla, cswift, nuron, gmp,
   sureware and ubsec.

   *Matt Caswell, Rich Salz*

 * New ASN.1 embed macro.

   New ASN.1 macro ASN1_EMBED. This is the same as ASN1_SIMPLE except the
   structure is not allocated: it is part of the parent. That is instead of

           FOO *x;

   it must be:

           FOO x;

   This reduces memory fragmentation and make it impossible to accidentally
   set a mandatory field to NULL.

   This currently only works for some fields specifically a SEQUENCE, CHOICE,
   or ASN1_STRING type which is part of a parent SEQUENCE. Since it is
   equivalent to ASN1_SIMPLE it cannot be tagged, OPTIONAL, SET OF or
   SEQUENCE OF.

   *Steve Henson*

 * Remove EVP_CHECK_DES_KEY, a compile-time option that never compiled.

   *Emilia Käsper*

 * Removed DES and RC4 ciphersuites from DEFAULT. Also removed RC2 although
   in 1.0.2 EXPORT was already removed and the only RC2 ciphersuite is also
   an EXPORT one. COMPLEMENTOFDEFAULT has been updated accordingly to add
   DES and RC4 ciphersuites.

   *Matt Caswell*

 * Rewrite EVP_DecodeUpdate (base64 decoding) to fix several bugs.
   This changes the decoding behaviour for some invalid messages,
   though the change is mostly in the more lenient direction, and
   legacy behaviour is preserved as much as possible.

   *Emilia Käsper*

 * Fix no-stdio build.
   *David Woodhouse <David.Woodhouse@intel.com> and also*
   *Ivan Nestlerode <ivan.nestlerode@sonos.com>*

 * New testing framework
   The testing framework has been largely rewritten and is now using
   perl and the perl modules Test::Harness and an extended variant of
   Test::More called OpenSSL::Test to do its work.  All test scripts in
   test/ have been rewritten into test recipes, and all direct calls to
   executables in test/Makefile have become individual recipes using the
   simplified testing OpenSSL::Test::Simple.

   For documentation on our testing modules, do:

           perldoc test/testlib/OpenSSL/Test/Simple.pm
           perldoc test/testlib/OpenSSL/Test.pm

   *Richard Levitte*

 * Revamped memory debug; only -DCRYPTO_MDEBUG and -DCRYPTO_MDEBUG_ABORT
   are used; the latter aborts on memory leaks (usually checked on exit).
   Some undocumented "set malloc, etc., hooks" functions were removed
   and others were changed.  All are now documented.

   *Rich Salz*

 * In DSA_generate_parameters_ex, if the provided seed is too short,
   return an error

   *Rich Salz and Ismo Puustinen <ismo.puustinen@intel.com>*

 * Rewrite PSK to support ECDHE_PSK, DHE_PSK and RSA_PSK. Add ciphersuites
   from RFC4279, RFC4785, RFC5487, RFC5489.

   Thanks to Christian J. Dietrich and Giuseppe D'Angelo for the
   original RSA_PSK patch.

   *Steve Henson*

 * Dropped support for the SSL3_FLAGS_DELAY_CLIENT_FINISHED flag. This SSLeay
   era flag was never set throughout the codebase (only read). Also removed
   SSL3_FLAGS_POP_BUFFER which was only used if
   SSL3_FLAGS_DELAY_CLIENT_FINISHED was also set.

   *Matt Caswell*

 * Changed the default name options in the "ca", "crl", "req" and "x509"
   to be "oneline" instead of "compat".

   *Richard Levitte*

 * Remove SSL_OP_TLS_BLOCK_PADDING_BUG. This is SSLeay legacy, we're
   not aware of clients that still exhibit this bug, and the workaround
   hasn't been working properly for a while.

   *Emilia Käsper*

 * The return type of BIO_number_read() and BIO_number_written() as well as
   the corresponding num_read and num_write members in the BIO structure has
   changed from unsigned long to uint64_t. On platforms where an unsigned
   long is 32 bits (e.g. Windows) these counters could overflow if >4Gb is
   transferred.

   *Matt Caswell*

 * Given the pervasive nature of TLS extensions it is inadvisable to run
   OpenSSL without support for them. It also means that maintaining
   the OPENSSL_NO_TLSEXT option within the code is very invasive (and probably
   not well tested). Therefore, the OPENSSL_NO_TLSEXT option has been removed.

   *Matt Caswell*

 * Removed support for the two export grade static DH ciphersuites
   EXP-DH-RSA-DES-CBC-SHA and EXP-DH-DSS-DES-CBC-SHA. These two ciphersuites
   were newly added (along with a number of other static DH ciphersuites) to
   1.0.2. However the two export ones have *never* worked since they were
   introduced. It seems strange in any case to be adding new export
   ciphersuites, and given "logjam" it also does not seem correct to fix them.

   *Matt Caswell*

 * Version negotiation has been rewritten. In particular SSLv23_method(),
   SSLv23_client_method() and SSLv23_server_method() have been deprecated,
   and turned into macros which simply call the new preferred function names
   TLS_method(), TLS_client_method() and TLS_server_method(). All new code
   should use the new names instead. Also as part of this change the ssl23.h
   header file has been removed.

   *Matt Caswell*

 * Support for Kerberos ciphersuites in TLS (RFC2712) has been removed. This
   code and the associated standard is no longer considered fit-for-purpose.

   *Matt Caswell*

 * RT2547 was closed.  When generating a private key, try to make the
   output file readable only by the owner.  This behavior change might
   be noticeable when interacting with other software.

 * Documented all exdata functions.  Added CRYPTO_free_ex_index.
   Added a test.

   *Rich Salz*

 * Added HTTP GET support to the ocsp command.

   *Rich Salz*

 * Changed default digest for the dgst and enc commands from MD5 to
   sha256

   *Rich Salz*

 * RAND_pseudo_bytes has been deprecated. Users should use RAND_bytes instead.

   *Matt Caswell*

 * Added support for TLS extended master secret from
   draft-ietf-tls-session-hash-03.txt. Thanks for Alfredo Pironti for an
   initial patch which was a great help during development.

   *Steve Henson*

 * All libssl internal structures have been removed from the public header
   files, and the OPENSSL_NO_SSL_INTERN option has been removed (since it is
   now redundant). Users should not attempt to access internal structures
   directly. Instead they should use the provided API functions.

   *Matt Caswell*

 * config has been changed so that by default OPENSSL_NO_DEPRECATED is used.
   Access to deprecated functions can be re-enabled by running config with
   "enable-deprecated". In addition applications wishing to use deprecated
   functions must define OPENSSL_USE_DEPRECATED. Note that this new behaviour
   will, by default, disable some transitive includes that previously existed
   in the header files (e.g. ec.h will no longer, by default, include bn.h)

   *Matt Caswell*

 * Added support for OCB mode. OpenSSL has been granted a patent license
   compatible with the OpenSSL license for use of OCB. Details are available
   at <https://www.openssl.org/source/OCB-patent-grant-OpenSSL.pdf>. Support
   for OCB can be removed by calling config with no-ocb.

   *Matt Caswell*

 * SSLv2 support has been removed.  It still supports receiving an SSLv2
   compatible client hello.

   *Kurt Roeckx*

 * Increased the minimal RSA keysize from 256 to 512 bits [Rich Salz],
   done while fixing the error code for the key-too-small case.

   *Annie Yousar <a.yousar@informatik.hu-berlin.de>*

 * CA.sh has been removed; use CA.pl instead.

   *Rich Salz*

 * Removed old DES API.

   *Rich Salz*

 * Remove various unsupported platforms:
      Sony NEWS4
      BEOS and BEOS_R5
      NeXT
      SUNOS
      MPE/iX
      Sinix/ReliantUNIX RM400
      DGUX
      NCR
      Tandem
      Cray
      16-bit platforms such as WIN16

   *Rich Salz*

 * Clean up OPENSSL_NO_xxx #define's
   - Use setbuf() and remove OPENSSL_NO_SETVBUF_IONBF
   - Rename OPENSSL_SYSNAME_xxx to OPENSSL_SYS_xxx
   - OPENSSL_NO_EC{DH,DSA} merged into OPENSSL_NO_EC
   - OPENSSL_NO_RIPEMD160, OPENSSL_NO_RIPEMD merged into OPENSSL_NO_RMD160
   - OPENSSL_NO_FP_API merged into OPENSSL_NO_STDIO
   - Remove OPENSSL_NO_BIO OPENSSL_NO_BUFFER OPENSSL_NO_CHAIN_VERIFY
     OPENSSL_NO_EVP OPENSSL_NO_FIPS_ERR OPENSSL_NO_HASH_COMP
     OPENSSL_NO_LHASH OPENSSL_NO_OBJECT OPENSSL_NO_SPEED OPENSSL_NO_STACK
     OPENSSL_NO_X509 OPENSSL_NO_X509_VERIFY
   - Remove MS_STATIC; it's a relic from platforms <32 bits.

   *Rich Salz*

 * Cleaned up dead code
     Remove all but one '#ifdef undef' which is to be looked at.

   *Rich Salz*

 * Clean up calling of xxx_free routines.
      Just like free(), fix most of the xxx_free routines to accept
      NULL.  Remove the non-null checks from callers.  Save much code.

   *Rich Salz*

 * Add secure heap for storage of private keys (when possible).
   Add BIO_s_secmem(), CBIGNUM, etc.
   Contributed by Akamai Technologies under our Corporate CLA.

   *Rich Salz*

 * Experimental support for a new, fast, unbiased prime candidate generator,
   bn_probable_prime_dh_coprime(). Not currently used by any prime generator.

   *Felix Laurie von Massenbach <felix@erbridge.co.uk>*

 * New output format NSS in the sess_id command line tool. This allows
   exporting the session id and the master key in NSS keylog format.

   *Martin Kaiser <martin@kaiser.cx>*

 * Harmonize version and its documentation. -f flag is used to display
   compilation flags.

   *mancha <mancha1@zoho.com>*

 * Fix eckey_priv_encode so it immediately returns an error upon a failure
   in i2d_ECPrivateKey.  Thanks to Ted Unangst for feedback on this issue.

   *mancha <mancha1@zoho.com>*

 * Fix some double frees. These are not thought to be exploitable.

   *mancha <mancha1@zoho.com>*

 * A missing bounds check in the handling of the TLS heartbeat extension
   can be used to reveal up to 64k of memory to a connected client or
   server.

   Thanks for Neel Mehta of Google Security for discovering this bug and to
   Adam Langley <agl@chromium.org> and Bodo Moeller <bmoeller@acm.org> for
   preparing the fix ([CVE-2014-0160])

   *Adam Langley, Bodo Moeller*

 * Fix for the attack described in the paper "Recovering OpenSSL
   ECDSA Nonces Using the FLUSH+RELOAD Cache Side-channel Attack"
   by Yuval Yarom and Naomi Benger. Details can be obtained from:
   <http://eprint.iacr.org/2014/140>

   Thanks to Yuval Yarom and Naomi Benger for discovering this
   flaw and to Yuval Yarom for supplying a fix ([CVE-2014-0076])

   *Yuval Yarom and Naomi Benger*

 * Use algorithm specific chains in SSL_CTX_use_certificate_chain_file():
   this fixes a limitation in previous versions of OpenSSL.

   *Steve Henson*

 * Experimental encrypt-then-mac support.

   Experimental support for encrypt then mac from
   draft-gutmann-tls-encrypt-then-mac-02.txt

   To enable it set the appropriate extension number (0x42 for the test
   server) using e.g. -DTLSEXT_TYPE_encrypt_then_mac=0x42

   For non-compliant peers (i.e. just about everything) this should have no
   effect.

   WARNING: EXPERIMENTAL, SUBJECT TO CHANGE.

   *Steve Henson*

 * Add EVP support for key wrapping algorithms, to avoid problems with
   existing code the flag EVP_CIPHER_CTX_WRAP_ALLOW has to be set in
   the EVP_CIPHER_CTX or an error is returned. Add AES and DES3 wrap
   algorithms and include tests cases.

   *Steve Henson*

 * Extend CMS code to support RSA-PSS signatures and RSA-OAEP for
   enveloped data.

   *Steve Henson*

 * Extended RSA OAEP support via EVP_PKEY API. Options to specify digest,
   MGF1 digest and OAEP label.

   *Steve Henson*

 * Make openssl verify return errors.

   *Chris Palmer <palmer@google.com> and Ben Laurie*

 * New function ASN1_TIME_diff to calculate the difference between two
   ASN1_TIME structures or one structure and the current time.

   *Steve Henson*

 * Update fips_test_suite to support multiple command line options. New
   test to induce all self test errors in sequence and check expected
   failures.

   *Steve Henson*

 * Add FIPS_{rsa,dsa,ecdsa}_{sign,verify} functions which digest and
   sign or verify all in one operation.

   *Steve Henson*

 * Add fips_algvs: a multicall fips utility incorporating all the algorithm
   test programs and fips_test_suite. Includes functionality to parse
   the minimal script output of fipsalgest.pl directly.

   *Steve Henson*

 * Add authorisation parameter to FIPS_module_mode_set().

   *Steve Henson*

 * Add FIPS selftest for ECDH algorithm using P-224 and B-233 curves.

   *Steve Henson*

 * Use separate DRBG fields for internal and external flags. New function
   FIPS_drbg_health_check() to perform on demand health checking. Add
   generation tests to fips_test_suite with reduced health check interval to
   demonstrate periodic health checking. Add "nodh" option to
   fips_test_suite to skip very slow DH test.

   *Steve Henson*

 * New function FIPS_get_cipherbynid() to lookup FIPS supported ciphers
   based on NID.

   *Steve Henson*

 * More extensive health check for DRBG checking many more failure modes.
   New function FIPS_selftest_drbg_all() to handle every possible DRBG
   combination: call this in fips_test_suite.

   *Steve Henson*

 * Add support for canonical generation of DSA parameter 'g'. See
   FIPS 186-3 A.2.3.

 * Add support for HMAC DRBG from SP800-90. Update DRBG algorithm test and
   POST to handle HMAC cases.

   *Steve Henson*

 * Add functions FIPS_module_version() and FIPS_module_version_text()
   to return numerical and string versions of the FIPS module number.

   *Steve Henson*

 * Rename FIPS_mode_set and FIPS_mode to FIPS_module_mode_set and
   FIPS_module_mode. FIPS_mode and FIPS_mode_set will be implemented
   outside the validated module in the FIPS capable OpenSSL.

   *Steve Henson*

 * Minor change to DRBG entropy callback semantics. In some cases
   there is no multiple of the block length between min_len and
   max_len. Allow the callback to return more than max_len bytes
   of entropy but discard any extra: it is the callback's responsibility
   to ensure that the extra data discarded does not impact the
   requested amount of entropy.

   *Steve Henson*

 * Add PRNG security strength checks to RSA, DSA and ECDSA using
   information in FIPS186-3, SP800-57 and SP800-131A.

   *Steve Henson*

 * CCM support via EVP. Interface is very similar to GCM case except we
   must supply all data in one chunk (i.e. no update, final) and the
   message length must be supplied if AAD is used. Add algorithm test
   support.

   *Steve Henson*

 * Initial version of POST overhaul. Add POST callback to allow the status
   of POST to be monitored and/or failures induced. Modify fips_test_suite
   to use callback. Always run all selftests even if one fails.

   *Steve Henson*

 * XTS support including algorithm test driver in the fips_gcmtest program.
   Note: this does increase the maximum key length from 32 to 64 bytes but
   there should be no binary compatibility issues as existing applications
   will never use XTS mode.

   *Steve Henson*

 * Extensive reorganisation of FIPS PRNG behaviour. Remove all dependencies
   to OpenSSL RAND code and replace with a tiny FIPS RAND API which also
   performs algorithm blocking for unapproved PRNG types. Also do not
   set PRNG type in FIPS_mode_set(): leave this to the application.
   Add default OpenSSL DRBG handling: sets up FIPS PRNG and seeds with
   the standard OpenSSL PRNG: set additional data to a date time vector.

   *Steve Henson*

 * Rename old X9.31 PRNG functions of the form `FIPS_rand*` to `FIPS_x931*`.
   This shouldn't present any incompatibility problems because applications
   shouldn't be using these directly and any that are will need to rethink
   anyway as the X9.31 PRNG is now deprecated by FIPS 140-2

   *Steve Henson*

 * Extensive self tests and health checking required by SP800-90 DRBG.
   Remove strength parameter from FIPS_drbg_instantiate and always
   instantiate at maximum supported strength.

   *Steve Henson*

 * Add ECDH code to fips module and fips_ecdhvs for primitives only testing.

   *Steve Henson*

 * New algorithm test program fips_dhvs to handle DH primitives only testing.

   *Steve Henson*

 * New function DH_compute_key_padded() to compute a DH key and pad with
   leading zeroes if needed: this complies with SP800-56A et al.

   *Steve Henson*

 * Initial implementation of SP800-90 DRBGs for Hash and CTR. Not used by
   anything, incomplete, subject to change and largely untested at present.

   *Steve Henson*

 * Modify fipscanisteronly build option to only build the necessary object
   files by filtering FIPS_EX_OBJ through a perl script in crypto/Makefile.

   *Steve Henson*

 * Add experimental option FIPSSYMS to give all symbols in
   fipscanister.o and FIPS or fips prefix. This will avoid
   conflicts with future versions of OpenSSL. Add perl script
   util/fipsas.pl to preprocess assembly language source files
   and rename any affected symbols.

   *Steve Henson*

 * Add selftest checks and algorithm block of non-fips algorithms in
   FIPS mode. Remove DES2 from selftests.

   *Steve Henson*

 * Add ECDSA code to fips module. Add tiny fips_ecdsa_check to just
   return internal method without any ENGINE dependencies. Add new
   tiny fips sign and verify functions.

   *Steve Henson*

 * New build option no-ec2m to disable characteristic 2 code.

   *Steve Henson*

 * New build option "fipscanisteronly". This only builds fipscanister.o
   and (currently) associated fips utilities. Uses the file Makefile.fips
   instead of Makefile.org as the prototype.

   *Steve Henson*

 * Add some FIPS mode restrictions to GCM. Add internal IV generator.
   Update fips_gcmtest to use IV generator.

   *Steve Henson*

 * Initial, experimental EVP support for AES-GCM. AAD can be input by
   setting output buffer to NULL. The `*Final` function must be
   called although it will not retrieve any additional data. The tag
   can be set or retrieved with a ctrl. The IV length is by default 12
   bytes (96 bits) but can be set to an alternative value. If the IV
   length exceeds the maximum IV length (currently 16 bytes) it cannot be
   set before the key.

   *Steve Henson*

 * New flag in ciphers: EVP_CIPH_FLAG_CUSTOM_CIPHER. This means the
   underlying do_cipher function handles all cipher semantics itself
   including padding and finalisation. This is useful if (for example)
   an ENGINE cipher handles block padding itself. The behaviour of
   do_cipher is subtly changed if this flag is set: the return value
   is the number of characters written to the output buffer (zero is
   no longer an error code) or a negative error code. Also if the
   input buffer is NULL and length 0 finalisation should be performed.

   *Steve Henson*

 * If a candidate issuer certificate is already part of the constructed
   path ignore it: new debug notification X509_V_ERR_PATH_LOOP for this case.

   *Steve Henson*

 * Improve forward-security support: add functions

           void SSL_CTX_set_not_resumable_session_callback(
                    SSL_CTX *ctx, int (*cb)(SSL *ssl, int is_forward_secure))
           void SSL_set_not_resumable_session_callback(
                    SSL *ssl, int (*cb)(SSL *ssl, int is_forward_secure))

   for use by SSL/TLS servers; the callback function will be called whenever a
   new session is created, and gets to decide whether the session may be
   cached to make it resumable (return 0) or not (return 1).  (As by the
   SSL/TLS protocol specifications, the session_id sent by the server will be
   empty to indicate that the session is not resumable; also, the server will
   not generate RFC 4507 (RFC 5077) session tickets.)

   A simple reasonable callback implementation is to return is_forward_secure.
   This parameter will be set to 1 or 0 depending on the ciphersuite selected
   by the SSL/TLS server library, indicating whether it can provide forward
   security.

   *Emilia Käsper <emilia.kasper@esat.kuleuven.be> (Google)*

 * New -verify_name option in command line utilities to set verification
   parameters by name.

   *Steve Henson*

 * Initial CMAC implementation. WARNING: EXPERIMENTAL, API MAY CHANGE.
   Add CMAC pkey methods.

   *Steve Henson*

 * Experimental renegotiation in s_server -www mode. If the client
   browses /reneg connection is renegotiated. If /renegcert it is
   renegotiated requesting a certificate.

   *Steve Henson*

 * Add an "external" session cache for debugging purposes to s_server. This
   should help trace issues which normally are only apparent in deployed
   multi-process servers.

   *Steve Henson*

 * Extensive audit of libcrypto with DEBUG_UNUSED. Fix many cases where
   return value is ignored. NB. The functions RAND_add(), RAND_seed(),
   BIO_set_cipher() and some obscure PEM functions were changed so they
   can now return an error. The RAND changes required a change to the
   RAND_METHOD structure.

   *Steve Henson*

 * New macro `__owur` for "OpenSSL Warn Unused Result". This makes use of
   a gcc attribute to warn if the result of a function is ignored. This
   is enable if DEBUG_UNUSED is set. Add to several functions in evp.h
   whose return value is often ignored.

   *Steve Henson*

 * New -noct, -requestct, -requirect and -ctlogfile options for s_client.
   These allow SCTs (signed certificate timestamps) to be requested and
   validated when establishing a connection.

   *Rob Percival <robpercival@google.com>*

OpenSSL 1.0.2
-------------

### Changes between 1.0.2s and 1.0.2t [10 Sep 2019]

 * For built-in EC curves, ensure an EC_GROUP built from the curve name is
   used even when parsing explicit parameters, when loading a encoded key
   or calling `EC_GROUP_new_from_ecpkparameters()`/
   `EC_GROUP_new_from_ecparameters()`.
   This prevents bypass of security hardening and performance gains,
   especially for curves with specialized EC_METHODs.
   By default, if a key encoded with explicit parameters is loaded and later
   encoded, the output is still encoded with explicit parameters, even if
   internally a "named" EC_GROUP is used for computation.

   *Nicola Tuveri*

 * Compute ECC cofactors if not provided during EC_GROUP construction. Before
   this change, EC_GROUP_set_generator would accept order and/or cofactor as
   NULL. After this change, only the cofactor parameter can be NULL. It also
   does some minimal sanity checks on the passed order.
   ([CVE-2019-1547])

   *Billy Bob Brumley*

 * Fixed a padding oracle in PKCS7_dataDecode and CMS_decrypt_set1_pkey.
   An attack is simple, if the first CMS_recipientInfo is valid but the
   second CMS_recipientInfo is chosen ciphertext. If the second
   recipientInfo decodes to PKCS #1 v1.5 form plaintext, the correct
   encryption key will be replaced by garbage, and the message cannot be
   decoded, but if the RSA decryption fails, the correct encryption key is
   used and the recipient will not notice the attack.
   As a work around for this potential attack the length of the decrypted
   key must be equal to the cipher default key length, in case the
   certificate is not given and all recipientInfo are tried out.
   The old behaviour can be re-enabled in the CMS code by setting the
   CMS_DEBUG_DECRYPT flag.
   ([CVE-2019-1563])

   *Bernd Edlinger*

 * Document issue with installation paths in diverse Windows builds

   '/usr/local/ssl' is an unsafe prefix for location to install OpenSSL
   binaries and run-time config file.
   ([CVE-2019-1552])

   *Richard Levitte*

### Changes between 1.0.2r and 1.0.2s [28 May 2019]

 * Change the default RSA, DSA and DH size to 2048 bit instead of 1024.
   This changes the size when using the `genpkey` command when no size is given.
   It fixes an omission in earlier changes that changed all RSA, DSA and DH
   generation commands to use 2048 bits by default.

   *Kurt Roeckx*

 * Add FIPS support for Android Arm 64-bit

   Support for Android Arm 64-bit was added to the OpenSSL FIPS Object
   Module in Version 2.0.10. For some reason, the corresponding target
   'android64-aarch64' was missing OpenSSL 1.0.2, whence it could not be
   built with FIPS support on Android Arm 64-bit. This omission has been
   fixed.

   *Matthias St. Pierre*

### Changes between 1.0.2q and 1.0.2r [26 Feb 2019]

 * 0-byte record padding oracle

   If an application encounters a fatal protocol error and then calls
   SSL_shutdown() twice (once to send a close_notify, and once to receive one)
   then OpenSSL can respond differently to the calling application if a 0 byte
   record is received with invalid padding compared to if a 0 byte record is
   received with an invalid MAC. If the application then behaves differently
   based on that in a way that is detectable to the remote peer, then this
   amounts to a padding oracle that could be used to decrypt data.

   In order for this to be exploitable "non-stitched" ciphersuites must be in
   use. Stitched ciphersuites are optimised implementations of certain
   commonly used ciphersuites. Also the application must call SSL_shutdown()
   twice even if a protocol error has occurred (applications should not do
   this but some do anyway).

   This issue was discovered by Juraj Somorovsky, Robert Merget and Nimrod
   Aviram, with additional investigation by Steven Collison and Andrew
   Hourselt. It was reported to OpenSSL on 10th December 2018.
   ([CVE-2019-1559])

   *Matt Caswell*

 * Move strictness check from EVP_PKEY_asn1_new() to EVP_PKEY_asn1_add0().

   *Richard Levitte*

### Changes between 1.0.2p and 1.0.2q [20 Nov 2018]

 * Microarchitecture timing vulnerability in ECC scalar multiplication

   OpenSSL ECC scalar multiplication, used in e.g. ECDSA and ECDH, has been
   shown to be vulnerable to a microarchitecture timing side channel attack.
   An attacker with sufficient access to mount local timing attacks during
   ECDSA signature generation could recover the private key.

   This issue was reported to OpenSSL on 26th October 2018 by Alejandro
   Cabrera Aldaya, Billy Brumley, Sohaib ul Hassan, Cesar Pereida Garcia and
   Nicola Tuveri.
   ([CVE-2018-5407])

   *Billy Brumley*

 * Timing vulnerability in DSA signature generation

   The OpenSSL DSA signature algorithm has been shown to be vulnerable to a
   timing side channel attack. An attacker could use variations in the signing
   algorithm to recover the private key.

   This issue was reported to OpenSSL on 16th October 2018 by Samuel Weiser.
   ([CVE-2018-0734])

   *Paul Dale*

 * Resolve a compatibility issue in EC_GROUP handling with the FIPS Object
   Module, accidentally introduced while backporting security fixes from the
   development branch and hindering the use of ECC in FIPS mode.

   *Nicola Tuveri*

### Changes between 1.0.2o and 1.0.2p [14 Aug 2018]

 * Client DoS due to large DH parameter

   During key agreement in a TLS handshake using a DH(E) based ciphersuite a
   malicious server can send a very large prime value to the client. This will
   cause the client to spend an unreasonably long period of time generating a
   key for this prime resulting in a hang until the client has finished. This
   could be exploited in a Denial Of Service attack.

   This issue was reported to OpenSSL on 5th June 2018 by Guido Vranken
   ([CVE-2018-0732])

   *Guido Vranken*

 * Cache timing vulnerability in RSA Key Generation

   The OpenSSL RSA Key generation algorithm has been shown to be vulnerable to
   a cache timing side channel attack. An attacker with sufficient access to
   mount cache timing attacks during the RSA key generation process could
   recover the private key.

   This issue was reported to OpenSSL on 4th April 2018 by Alejandro Cabrera
   Aldaya, Billy Brumley, Cesar Pereida Garcia and Luis Manuel Alvarez Tapia.
   ([CVE-2018-0737])

   *Billy Brumley*

 * Make EVP_PKEY_asn1_new() a bit stricter about its input.  A NULL pem_str
   parameter is no longer accepted, as it leads to a corrupt table.  NULL
   pem_str is reserved for alias entries only.

   *Richard Levitte*

 * Revert blinding in ECDSA sign and instead make problematic addition
   length-invariant. Switch even to fixed-length Montgomery multiplication.

   *Andy Polyakov*

 * Change generating and checking of primes so that the error rate of not
   being prime depends on the intended use based on the size of the input.
   For larger primes this will result in more rounds of Miller-Rabin.
   The maximal error rate for primes with more than 1080 bits is lowered
   to 2^-128.

   *Kurt Roeckx, Annie Yousar*

 * Increase the number of Miller-Rabin rounds for DSA key generating to 64.

   *Kurt Roeckx*

 * Add blinding to ECDSA and DSA signatures to protect against side channel
   attacks discovered by Keegan Ryan (NCC Group).

   *Matt Caswell*

 * When unlocking a pass phrase protected PEM file or PKCS#8 container, we
   now allow empty (zero character) pass phrases.

   *Richard Levitte*

 * Certificate time validation (X509_cmp_time) enforces stricter
   compliance with RFC 5280. Fractional seconds and timezone offsets
   are no longer allowed.

   *Emilia Käsper*

### Changes between 1.0.2n and 1.0.2o [27 Mar 2018]

 * Constructed ASN.1 types with a recursive definition could exceed the stack

   Constructed ASN.1 types with a recursive definition (such as can be found
   in PKCS7) could eventually exceed the stack given malicious input with
   excessive recursion. This could result in a Denial Of Service attack. There
   are no such structures used within SSL/TLS that come from untrusted sources
   so this is considered safe.

   This issue was reported to OpenSSL on 4th January 2018 by the OSS-fuzz
   project.
   ([CVE-2018-0739])

   *Matt Caswell*

### Changes between 1.0.2m and 1.0.2n [7 Dec 2017]

 * Read/write after SSL object in error state

   OpenSSL 1.0.2 (starting from version 1.0.2b) introduced an "error state"
   mechanism. The intent was that if a fatal error occurred during a handshake
   then OpenSSL would move into the error state and would immediately fail if
   you attempted to continue the handshake. This works as designed for the
   explicit handshake functions (SSL_do_handshake(), SSL_accept() and
   SSL_connect()), however due to a bug it does not work correctly if
   SSL_read() or SSL_write() is called directly. In that scenario, if the
   handshake fails then a fatal error will be returned in the initial function
   call. If SSL_read()/SSL_write() is subsequently called by the application
   for the same SSL object then it will succeed and the data is passed without
   being decrypted/encrypted directly from the SSL/TLS record layer.

   In order to exploit this issue an application bug would have to be present
   that resulted in a call to SSL_read()/SSL_write() being issued after having
   already received a fatal error.

   This issue was reported to OpenSSL by David Benjamin (Google).
   ([CVE-2017-3737])

   *Matt Caswell*

 * rsaz_1024_mul_avx2 overflow bug on x86_64

   There is an overflow bug in the AVX2 Montgomery multiplication procedure
   used in exponentiation with 1024-bit moduli. No EC algorithms are affected.
   Analysis suggests that attacks against RSA and DSA as a result of this
   defect would be very difficult to perform and are not believed likely.
   Attacks against DH1024 are considered just feasible, because most of the
   work necessary to deduce information about a private key may be performed
   offline. The amount of resources required for such an attack would be
   significant. However, for an attack on TLS to be meaningful, the server
   would have to share the DH1024 private key among multiple clients, which is
   no longer an option since CVE-2016-0701.

   This only affects processors that support the AVX2 but not ADX extensions
   like Intel Haswell (4th generation).

   This issue was reported to OpenSSL by David Benjamin (Google). The issue
   was originally found via the OSS-Fuzz project.
   ([CVE-2017-3738])

   *Andy Polyakov*

### Changes between 1.0.2l and 1.0.2m [2 Nov 2017]

 * bn_sqrx8x_internal carry bug on x86_64

   There is a carry propagating bug in the x86_64 Montgomery squaring
   procedure. No EC algorithms are affected. Analysis suggests that attacks
   against RSA and DSA as a result of this defect would be very difficult to
   perform and are not believed likely. Attacks against DH are considered just
   feasible (although very difficult) because most of the work necessary to
   deduce information about a private key may be performed offline. The amount
   of resources required for such an attack would be very significant and
   likely only accessible to a limited number of attackers. An attacker would
   additionally need online access to an unpatched system using the target
   private key in a scenario with persistent DH parameters and a private
   key that is shared between multiple clients.

   This only affects processors that support the BMI1, BMI2 and ADX extensions
   like Intel Broadwell (5th generation) and later or AMD Ryzen.

   This issue was reported to OpenSSL by the OSS-Fuzz project.
   ([CVE-2017-3736])

   *Andy Polyakov*

 * Malformed X.509 IPAddressFamily could cause OOB read

   If an X.509 certificate has a malformed IPAddressFamily extension,
   OpenSSL could do a one-byte buffer overread. The most likely result
   would be an erroneous display of the certificate in text format.

   This issue was reported to OpenSSL by the OSS-Fuzz project.

   *Rich Salz*

### Changes between 1.0.2k and 1.0.2l [25 May 2017]

 * Have 'config' recognise 64-bit mingw and choose 'mingw64' as the target
   platform rather than 'mingw'.

   *Richard Levitte*

### Changes between 1.0.2j and 1.0.2k [26 Jan 2017]

 * Truncated packet could crash via OOB read

   If one side of an SSL/TLS path is running on a 32-bit host and a specific
   cipher is being used, then a truncated packet can cause that host to
   perform an out-of-bounds read, usually resulting in a crash.

   This issue was reported to OpenSSL by Robert Święcki of Google.
   ([CVE-2017-3731])

   *Andy Polyakov*

 * BN_mod_exp may produce incorrect results on x86_64

   There is a carry propagating bug in the x86_64 Montgomery squaring
   procedure. No EC algorithms are affected. Analysis suggests that attacks
   against RSA and DSA as a result of this defect would be very difficult to
   perform and are not believed likely. Attacks against DH are considered just
   feasible (although very difficult) because most of the work necessary to
   deduce information about a private key may be performed offline. The amount
   of resources required for such an attack would be very significant and
   likely only accessible to a limited number of attackers. An attacker would
   additionally need online access to an unpatched system using the target
   private key in a scenario with persistent DH parameters and a private
   key that is shared between multiple clients. For example this can occur by
   default in OpenSSL DHE based SSL/TLS ciphersuites. Note: This issue is very
   similar to CVE-2015-3193 but must be treated as a separate problem.

   This issue was reported to OpenSSL by the OSS-Fuzz project.
   ([CVE-2017-3732])

   *Andy Polyakov*

 * Montgomery multiplication may produce incorrect results

   There is a carry propagating bug in the Broadwell-specific Montgomery
   multiplication procedure that handles input lengths divisible by, but
   longer than 256 bits. Analysis suggests that attacks against RSA, DSA
   and DH private keys are impossible. This is because the subroutine in
   question is not used in operations with the private key itself and an input
   of the attacker's direct choice. Otherwise the bug can manifest itself as
   transient authentication and key negotiation failures or reproducible
   erroneous outcome of public-key operations with specially crafted input.
   Among EC algorithms only Brainpool P-512 curves are affected and one
   presumably can attack ECDH key negotiation. Impact was not analyzed in
   detail, because pre-requisites for attack are considered unlikely. Namely
   multiple clients have to choose the curve in question and the server has to
   share the private key among them, neither of which is default behaviour.
   Even then only clients that chose the curve will be affected.

   This issue was publicly reported as transient failures and was not
   initially recognized as a security issue. Thanks to Richard Morgan for
   providing reproducible case.
   ([CVE-2016-7055])

   *Andy Polyakov*

 * OpenSSL now fails if it receives an unrecognised record type in TLS1.0
   or TLS1.1. Previously this only happened in SSLv3 and TLS1.2. This is to
   prevent issues where no progress is being made and the peer continually
   sends unrecognised record types, using up resources processing them.

   *Matt Caswell*

### Changes between 1.0.2i and 1.0.2j [26 Sep 2016]

 * Missing CRL sanity check

   A bug fix which included a CRL sanity check was added to OpenSSL 1.1.0
   but was omitted from OpenSSL 1.0.2i. As a result any attempt to use
   CRLs in OpenSSL 1.0.2i will crash with a null pointer exception.

   This issue only affects the OpenSSL 1.0.2i
   ([CVE-2016-7052])

   *Matt Caswell*

### Changes between 1.0.2h and 1.0.2i [22 Sep 2016]

 * OCSP Status Request extension unbounded memory growth

   A malicious client can send an excessively large OCSP Status Request
   extension. If that client continually requests renegotiation, sending a
   large OCSP Status Request extension each time, then there will be unbounded
   memory growth on the server. This will eventually lead to a Denial Of
   Service attack through memory exhaustion. Servers with a default
   configuration are vulnerable even if they do not support OCSP. Builds using
   the "no-ocsp" build time option are not affected.

   This issue was reported to OpenSSL by Shi Lei (Gear Team, Qihoo 360 Inc.)
   ([CVE-2016-6304])

   *Matt Caswell*

 * In order to mitigate the SWEET32 attack, the DES ciphers were moved from
   HIGH to MEDIUM.

   This issue was reported to OpenSSL Karthikeyan Bhargavan and Gaetan
   Leurent (INRIA)
   ([CVE-2016-2183])

   *Rich Salz*

 * OOB write in MDC2_Update()

   An overflow can occur in MDC2_Update() either if called directly or
   through the EVP_DigestUpdate() function using MDC2. If an attacker
   is able to supply very large amounts of input data after a previous
   call to EVP_EncryptUpdate() with a partial block then a length check
   can overflow resulting in a heap corruption.

   The amount of data needed is comparable to SIZE_MAX which is impractical
   on most platforms.

   This issue was reported to OpenSSL by Shi Lei (Gear Team, Qihoo 360 Inc.)
   ([CVE-2016-6303])

   *Stephen Henson*

 * Malformed SHA512 ticket DoS

   If a server uses SHA512 for TLS session ticket HMAC it is vulnerable to a
   DoS attack where a malformed ticket will result in an OOB read which will
   ultimately crash.

   The use of SHA512 in TLS session tickets is comparatively rare as it requires
   a custom server callback and ticket lookup mechanism.

   This issue was reported to OpenSSL by Shi Lei (Gear Team, Qihoo 360 Inc.)
   ([CVE-2016-6302])

   *Stephen Henson*

 * OOB write in BN_bn2dec()

   The function BN_bn2dec() does not check the return value of BN_div_word().
   This can cause an OOB write if an application uses this function with an
   overly large BIGNUM. This could be a problem if an overly large certificate
   or CRL is printed out from an untrusted source. TLS is not affected because
   record limits will reject an oversized certificate before it is parsed.

   This issue was reported to OpenSSL by Shi Lei (Gear Team, Qihoo 360 Inc.)
   ([CVE-2016-2182])

   *Stephen Henson*

 * OOB read in TS_OBJ_print_bio()

   The function TS_OBJ_print_bio() misuses OBJ_obj2txt(): the return value is
   the total length the OID text representation would use and not the amount
   of data written. This will result in OOB reads when large OIDs are
   presented.

   This issue was reported to OpenSSL by Shi Lei (Gear Team, Qihoo 360 Inc.)
   ([CVE-2016-2180])

   *Stephen Henson*

 * Pointer arithmetic undefined behaviour

   Avoid some undefined pointer arithmetic

   A common idiom in the codebase is to check limits in the following manner:
   "p + len > limit"

   Where "p" points to some malloc'd data of SIZE bytes and
   limit == p + SIZE

   "len" here could be from some externally supplied data (e.g. from a TLS
   message).

   The rules of C pointer arithmetic are such that "p + len" is only well
   defined where len <= SIZE. Therefore the above idiom is actually
   undefined behaviour.

   For example this could cause problems if some malloc implementation
   provides an address for "p" such that "p + len" actually overflows for
   values of len that are too big and therefore p + len < limit.

   This issue was reported to OpenSSL by Guido Vranken
   ([CVE-2016-2177])

   *Matt Caswell*

 * Constant time flag not preserved in DSA signing

   Operations in the DSA signing algorithm should run in constant time in
   order to avoid side channel attacks. A flaw in the OpenSSL DSA
   implementation means that a non-constant time codepath is followed for
   certain operations. This has been demonstrated through a cache-timing
   attack to be sufficient for an attacker to recover the private DSA key.

   This issue was reported by César Pereida (Aalto University), Billy Brumley
   (Tampere University of Technology), and Yuval Yarom (The University of
   Adelaide and NICTA).
   ([CVE-2016-2178])

   *César Pereida*

 * DTLS buffered message DoS

   In a DTLS connection where handshake messages are delivered out-of-order
   those messages that OpenSSL is not yet ready to process will be buffered
   for later use. Under certain circumstances, a flaw in the logic means that
   those messages do not get removed from the buffer even though the handshake
   has been completed. An attacker could force up to approx. 15 messages to
   remain in the buffer when they are no longer required. These messages will
   be cleared when the DTLS connection is closed. The default maximum size for
   a message is 100k. Therefore, the attacker could force an additional 1500k
   to be consumed per connection. By opening many simultaneous connections an
   attacker could cause a DoS attack through memory exhaustion.

   This issue was reported to OpenSSL by Quan Luo.
   ([CVE-2016-2179])

   *Matt Caswell*

 * DTLS replay protection DoS

   A flaw in the DTLS replay attack protection mechanism means that records
   that arrive for future epochs update the replay protection "window" before
   the MAC for the record has been validated. This could be exploited by an
   attacker by sending a record for the next epoch (which does not have to
   decrypt or have a valid MAC), with a very large sequence number. This means
   that all subsequent legitimate packets are dropped causing a denial of
   service for a specific DTLS connection.

   This issue was reported to OpenSSL by the OCAP audit team.
   ([CVE-2016-2181])

   *Matt Caswell*

 * Certificate message OOB reads

   In OpenSSL 1.0.2 and earlier some missing message length checks can result
   in OOB reads of up to 2 bytes beyond an allocated buffer. There is a
   theoretical DoS risk but this has not been observed in practice on common
   platforms.

   The messages affected are client certificate, client certificate request
   and server certificate. As a result the attack can only be performed
   against a client or a server which enables client authentication.

   This issue was reported to OpenSSL by Shi Lei (Gear Team, Qihoo 360 Inc.)
   ([CVE-2016-6306])

   *Stephen Henson*

### Changes between 1.0.2g and 1.0.2h [3 May 2016]

 * Prevent padding oracle in AES-NI CBC MAC check

   A MITM attacker can use a padding oracle attack to decrypt traffic
   when the connection uses an AES CBC cipher and the server support
   AES-NI.

   This issue was introduced as part of the fix for Lucky 13 padding
   attack ([CVE-2013-0169]). The padding check was rewritten to be in
   constant time by making sure that always the same bytes are read and
   compared against either the MAC or padding bytes. But it no longer
   checked that there was enough data to have both the MAC and padding
   bytes.

   This issue was reported by Juraj Somorovsky using TLS-Attacker.

   *Kurt Roeckx*

 * Fix EVP_EncodeUpdate overflow

   An overflow can occur in the EVP_EncodeUpdate() function which is used for
   Base64 encoding of binary data. If an attacker is able to supply very large
   amounts of input data then a length check can overflow resulting in a heap
   corruption.

   Internally to OpenSSL the EVP_EncodeUpdate() function is primarily used by
   the `PEM_write_bio*` family of functions. These are mainly used within the
   OpenSSL command line applications, so any application which processes data
   from an untrusted source and outputs it as a PEM file should be considered
   vulnerable to this issue. User applications that call these APIs directly
   with large amounts of untrusted data may also be vulnerable.

   This issue was reported by Guido Vranken.
   ([CVE-2016-2105])

   *Matt Caswell*

 * Fix EVP_EncryptUpdate overflow

   An overflow can occur in the EVP_EncryptUpdate() function. If an attacker
   is able to supply very large amounts of input data after a previous call to
   EVP_EncryptUpdate() with a partial block then a length check can overflow
   resulting in a heap corruption. Following an analysis of all OpenSSL
   internal usage of the EVP_EncryptUpdate() function all usage is one of two
   forms. The first form is where the EVP_EncryptUpdate() call is known to be
   the first called function after an EVP_EncryptInit(), and therefore that
   specific call must be safe. The second form is where the length passed to
   EVP_EncryptUpdate() can be seen from the code to be some small value and
   therefore there is no possibility of an overflow. Since all instances are
   one of these two forms, it is believed that there can be no overflows in
   internal code due to this problem. It should be noted that
   EVP_DecryptUpdate() can call EVP_EncryptUpdate() in certain code paths.
   Also EVP_CipherUpdate() is a synonym for EVP_EncryptUpdate(). All instances
   of these calls have also been analysed too and it is believed there are no
   instances in internal usage where an overflow could occur.

   This issue was reported by Guido Vranken.
   ([CVE-2016-2106])

   *Matt Caswell*

 * Prevent ASN.1 BIO excessive memory allocation

   When ASN.1 data is read from a BIO using functions such as d2i_CMS_bio()
   a short invalid encoding can cause allocation of large amounts of memory
   potentially consuming excessive resources or exhausting memory.

   Any application parsing untrusted data through d2i BIO functions is
   affected. The memory based functions such as d2i_X509() are *not* affected.
   Since the memory based functions are used by the TLS library, TLS
   applications are not affected.

   This issue was reported by Brian Carpenter.
   ([CVE-2016-2109])

   *Stephen Henson*

 * EBCDIC overread

   ASN1 Strings that are over 1024 bytes can cause an overread in applications
   using the X509_NAME_oneline() function on EBCDIC systems. This could result
   in arbitrary stack data being returned in the buffer.

   This issue was reported by Guido Vranken.
   ([CVE-2016-2176])

   *Matt Caswell*

 * Modify behavior of ALPN to invoke callback after SNI/servername
   callback, such that updates to the SSL_CTX affect ALPN.

   *Todd Short*

 * Remove LOW from the DEFAULT cipher list.  This removes singles DES from the
   default.

   *Kurt Roeckx*

 * Only remove the SSLv2 methods with the no-ssl2-method option. When the
   methods are enabled and ssl2 is disabled the methods return NULL.

   *Kurt Roeckx*

### Changes between 1.0.2f and 1.0.2g [1 Mar 2016]

* Disable weak ciphers in SSLv3 and up in default builds of OpenSSL.
  Builds that are not configured with "enable-weak-ssl-ciphers" will not
  provide any "EXPORT" or "LOW" strength ciphers.

  *Viktor Dukhovni*

* Disable SSLv2 default build, default negotiation and weak ciphers.  SSLv2
  is by default disabled at build-time.  Builds that are not configured with
  "enable-ssl2" will not support SSLv2.  Even if "enable-ssl2" is used,
  users who want to negotiate SSLv2 via the version-flexible SSLv23_method()
  will need to explicitly call either of:

      SSL_CTX_clear_options(ctx, SSL_OP_NO_SSLv2);
  or
      SSL_clear_options(ssl, SSL_OP_NO_SSLv2);

  as appropriate.  Even if either of those is used, or the application
  explicitly uses the version-specific SSLv2_method() or its client and
  server variants, SSLv2 ciphers vulnerable to exhaustive search key
  recovery have been removed.  Specifically, the SSLv2 40-bit EXPORT
  ciphers, and SSLv2 56-bit DES are no longer available.
  ([CVE-2016-0800])

   *Viktor Dukhovni*

 * Fix a double-free in DSA code

   A double free bug was discovered when OpenSSL parses malformed DSA private
   keys and could lead to a DoS attack or memory corruption for applications
   that receive DSA private keys from untrusted sources.  This scenario is
   considered rare.

   This issue was reported to OpenSSL by Adam Langley(Google/BoringSSL) using
   libFuzzer.
   ([CVE-2016-0705])

   *Stephen Henson*

 * Disable SRP fake user seed to address a server memory leak.

   Add a new method SRP_VBASE_get1_by_user that handles the seed properly.

   SRP_VBASE_get_by_user had inconsistent memory management behaviour.
   In order to fix an unavoidable memory leak, SRP_VBASE_get_by_user
   was changed to ignore the "fake user" SRP seed, even if the seed
   is configured.

   Users should use SRP_VBASE_get1_by_user instead. Note that in
   SRP_VBASE_get1_by_user, caller must free the returned value. Note
   also that even though configuring the SRP seed attempts to hide
   invalid usernames by continuing the handshake with fake
   credentials, this behaviour is not constant time and no strong
   guarantees are made that the handshake is indistinguishable from
   that of a valid user.
   ([CVE-2016-0798])

   *Emilia Käsper*

 * Fix BN_hex2bn/BN_dec2bn NULL pointer deref/heap corruption

   In the BN_hex2bn function the number of hex digits is calculated using an
   int value `i`. Later `bn_expand` is called with a value of `i * 4`. For
   large values of `i` this can result in `bn_expand` not allocating any
   memory because `i * 4` is negative. This can leave the internal BIGNUM data
   field as NULL leading to a subsequent NULL ptr deref. For very large values
   of `i`, the calculation `i * 4` could be a positive value smaller than `i`.
   In this case memory is allocated to the internal BIGNUM data field, but it
   is insufficiently sized leading to heap corruption. A similar issue exists
   in BN_dec2bn. This could have security consequences if BN_hex2bn/BN_dec2bn
   is ever called by user applications with very large untrusted hex/dec data.
   This is anticipated to be a rare occurrence.

   All OpenSSL internal usage of these functions use data that is not expected
   to be untrusted, e.g. config file data or application command line
   arguments. If user developed applications generate config file data based
   on untrusted data then it is possible that this could also lead to security
   consequences. This is also anticipated to be rare.

   This issue was reported to OpenSSL by Guido Vranken.
   ([CVE-2016-0797])

   *Matt Caswell*

 * Fix memory issues in `BIO_*printf` functions

   The internal `fmtstr` function used in processing a "%s" format string in
   the `BIO_*printf` functions could overflow while calculating the length of a
   string and cause an OOB read when printing very long strings.

   Additionally the internal `doapr_outch` function can attempt to write to an
   OOB memory location (at an offset from the NULL pointer) in the event of a
   memory allocation failure. In 1.0.2 and below this could be caused where
   the size of a buffer to be allocated is greater than INT_MAX. E.g. this
   could be in processing a very long "%s" format string. Memory leaks can
   also occur.

   The first issue may mask the second issue dependent on compiler behaviour.
   These problems could enable attacks where large amounts of untrusted data
   is passed to the `BIO_*printf` functions. If applications use these functions
   in this way then they could be vulnerable. OpenSSL itself uses these
   functions when printing out human-readable dumps of ASN.1 data. Therefore
   applications that print this data could be vulnerable if the data is from
   untrusted sources. OpenSSL command line applications could also be
   vulnerable where they print out ASN.1 data, or if untrusted data is passed
   as command line arguments.

   Libssl is not considered directly vulnerable. Additionally certificates etc
   received via remote connections via libssl are also unlikely to be able to
   trigger these issues because of message size limits enforced within libssl.

   This issue was reported to OpenSSL Guido Vranken.
   ([CVE-2016-0799])

   *Matt Caswell*

 * Side channel attack on modular exponentiation

   A side-channel attack was found which makes use of cache-bank conflicts on
   the Intel Sandy-Bridge microarchitecture which could lead to the recovery
   of RSA keys.  The ability to exploit this issue is limited as it relies on
   an attacker who has control of code in a thread running on the same
   hyper-threaded core as the victim thread which is performing decryptions.

   This issue was reported to OpenSSL by Yuval Yarom, The University of
   Adelaide and NICTA, Daniel Genkin, Technion and Tel Aviv University, and
   Nadia Heninger, University of Pennsylvania with more information at
   <http://cachebleed.info>.
   ([CVE-2016-0702])

   *Andy Polyakov*

 * Change the `req` command to generate a 2048-bit RSA/DSA key by default,
   if no keysize is specified with default_bits. This fixes an
   omission in an earlier change that changed all RSA/DSA key generation
   commands to use 2048 bits by default.

   *Emilia Käsper*

### Changes between 1.0.2e and 1.0.2f [28 Jan 2016]

 * DH small subgroups

   Historically OpenSSL only ever generated DH parameters based on "safe"
   primes. More recently (in version 1.0.2) support was provided for
   generating X9.42 style parameter files such as those required for RFC 5114
   support. The primes used in such files may not be "safe". Where an
   application is using DH configured with parameters based on primes that are
   not "safe" then an attacker could use this fact to find a peer's private
   DH exponent. This attack requires that the attacker complete multiple
   handshakes in which the peer uses the same private DH exponent. For example
   this could be used to discover a TLS server's private DH exponent if it's
   reusing the private DH exponent or it's using a static DH ciphersuite.

   OpenSSL provides the option SSL_OP_SINGLE_DH_USE for ephemeral DH (DHE) in
   TLS. It is not on by default. If the option is not set then the server
   reuses the same private DH exponent for the life of the server process and
   would be vulnerable to this attack. It is believed that many popular
   applications do set this option and would therefore not be at risk.

   The fix for this issue adds an additional check where a "q" parameter is
   available (as is the case in X9.42 based parameters). This detects the
   only known attack, and is the only possible defense for static DH
   ciphersuites. This could have some performance impact.

   Additionally the SSL_OP_SINGLE_DH_USE option has been switched on by
   default and cannot be disabled. This could have some performance impact.

   This issue was reported to OpenSSL by Antonio Sanso (Adobe).
   ([CVE-2016-0701])

   *Matt Caswell*

 * SSLv2 doesn't block disabled ciphers

   A malicious client can negotiate SSLv2 ciphers that have been disabled on
   the server and complete SSLv2 handshakes even if all SSLv2 ciphers have
   been disabled, provided that the SSLv2 protocol was not also disabled via
   SSL_OP_NO_SSLv2.

   This issue was reported to OpenSSL on 26th December 2015 by Nimrod Aviram
   and Sebastian Schinzel.
   ([CVE-2015-3197])

   *Viktor Dukhovni*

### Changes between 1.0.2d and 1.0.2e [3 Dec 2015]

 * BN_mod_exp may produce incorrect results on x86_64

   There is a carry propagating bug in the x86_64 Montgomery squaring
   procedure. No EC algorithms are affected. Analysis suggests that attacks
   against RSA and DSA as a result of this defect would be very difficult to
   perform and are not believed likely. Attacks against DH are considered just
   feasible (although very difficult) because most of the work necessary to
   deduce information about a private key may be performed offline. The amount
   of resources required for such an attack would be very significant and
   likely only accessible to a limited number of attackers. An attacker would
   additionally need online access to an unpatched system using the target
   private key in a scenario with persistent DH parameters and a private
   key that is shared between multiple clients. For example this can occur by
   default in OpenSSL DHE based SSL/TLS ciphersuites.

   This issue was reported to OpenSSL by Hanno Böck.
   ([CVE-2015-3193])

   *Andy Polyakov*

 * Certificate verify crash with missing PSS parameter

   The signature verification routines will crash with a NULL pointer
   dereference if presented with an ASN.1 signature using the RSA PSS
   algorithm and absent mask generation function parameter. Since these
   routines are used to verify certificate signature algorithms this can be
   used to crash any certificate verification operation and exploited in a
   DoS attack. Any application which performs certificate verification is
   vulnerable including OpenSSL clients and servers which enable client
   authentication.

   This issue was reported to OpenSSL by Loïc Jonas Etienne (Qnective AG).
   ([CVE-2015-3194])

   *Stephen Henson*

 * X509_ATTRIBUTE memory leak

   When presented with a malformed X509_ATTRIBUTE structure OpenSSL will leak
   memory. This structure is used by the PKCS#7 and CMS routines so any
   application which reads PKCS#7 or CMS data from untrusted sources is
   affected. SSL/TLS is not affected.

   This issue was reported to OpenSSL by Adam Langley (Google/BoringSSL) using
   libFuzzer.
   ([CVE-2015-3195])

   *Stephen Henson*

 * Rewrite EVP_DecodeUpdate (base64 decoding) to fix several bugs.
   This changes the decoding behaviour for some invalid messages,
   though the change is mostly in the more lenient direction, and
   legacy behaviour is preserved as much as possible.

   *Emilia Käsper*

 * In DSA_generate_parameters_ex, if the provided seed is too short,
   return an error

   *Rich Salz and Ismo Puustinen <ismo.puustinen@intel.com>*

### Changes between 1.0.2c and 1.0.2d [9 Jul 2015]

 * Alternate chains certificate forgery

   During certificate verification, OpenSSL will attempt to find an
   alternative certificate chain if the first attempt to build such a chain
   fails. An error in the implementation of this logic can mean that an
   attacker could cause certain checks on untrusted certificates to be
   bypassed, such as the CA flag, enabling them to use a valid leaf
   certificate to act as a CA and "issue" an invalid certificate.

   This issue was reported to OpenSSL by Adam Langley/David Benjamin
   (Google/BoringSSL).

   *Matt Caswell*

### Changes between 1.0.2b and 1.0.2c [12 Jun 2015]

 * Fix HMAC ABI incompatibility. The previous version introduced an ABI
   incompatibility in the handling of HMAC. The previous ABI has now been
   restored.

   *Matt Caswell*

### Changes between 1.0.2a and 1.0.2b [11 Jun 2015]

 * Malformed ECParameters causes infinite loop

   When processing an ECParameters structure OpenSSL enters an infinite loop
   if the curve specified is over a specially malformed binary polynomial
   field.

   This can be used to perform denial of service against any
   system which processes public keys, certificate requests or
   certificates.  This includes TLS clients and TLS servers with
   client authentication enabled.

   This issue was reported to OpenSSL by Joseph Barr-Pixton.
   ([CVE-2015-1788])

   *Andy Polyakov*

 * Exploitable out-of-bounds read in X509_cmp_time

   X509_cmp_time does not properly check the length of the ASN1_TIME
   string and can read a few bytes out of bounds. In addition,
   X509_cmp_time accepts an arbitrary number of fractional seconds in the
   time string.

   An attacker can use this to craft malformed certificates and CRLs of
   various sizes and potentially cause a segmentation fault, resulting in
   a DoS on applications that verify certificates or CRLs. TLS clients
   that verify CRLs are affected. TLS clients and servers with client
   authentication enabled may be affected if they use custom verification
   callbacks.

   This issue was reported to OpenSSL by Robert Swiecki (Google), and
   independently by Hanno Böck.
   ([CVE-2015-1789])

   *Emilia Käsper*

 * PKCS7 crash with missing EnvelopedContent

   The PKCS#7 parsing code does not handle missing inner EncryptedContent
   correctly. An attacker can craft malformed ASN.1-encoded PKCS#7 blobs
   with missing content and trigger a NULL pointer dereference on parsing.

   Applications that decrypt PKCS#7 data or otherwise parse PKCS#7
   structures from untrusted sources are affected. OpenSSL clients and
   servers are not affected.

   This issue was reported to OpenSSL by Michal Zalewski (Google).
   ([CVE-2015-1790])

   *Emilia Käsper*

 * CMS verify infinite loop with unknown hash function

   When verifying a signedData message the CMS code can enter an infinite loop
   if presented with an unknown hash function OID. This can be used to perform
   denial of service against any system which verifies signedData messages using
   the CMS code.
   This issue was reported to OpenSSL by Johannes Bauer.
   ([CVE-2015-1792])

   *Stephen Henson*

 * Race condition handling NewSessionTicket

   If a NewSessionTicket is received by a multi-threaded client when attempting to
   reuse a previous ticket then a race condition can occur potentially leading to
   a double free of the ticket data.
   ([CVE-2015-1791])

   *Matt Caswell*

 * Only support 256-bit or stronger elliptic curves with the
   'ecdh_auto' setting (server) or by default (client). Of supported
   curves, prefer P-256 (both).

   *Emilia Kasper*

### Changes between 1.0.2 and 1.0.2a [19 Mar 2015]

 * ClientHello sigalgs DoS fix

   If a client connects to an OpenSSL 1.0.2 server and renegotiates with an
   invalid signature algorithms extension a NULL pointer dereference will
   occur. This can be exploited in a DoS attack against the server.

   This issue was was reported to OpenSSL by David Ramos of Stanford
   University.
   ([CVE-2015-0291])

   *Stephen Henson and Matt Caswell*

 * Multiblock corrupted pointer fix

   OpenSSL 1.0.2 introduced the "multiblock" performance improvement. This
   feature only applies on 64 bit x86 architecture platforms that support AES
   NI instructions. A defect in the implementation of "multiblock" can cause
   OpenSSL's internal write buffer to become incorrectly set to NULL when
   using non-blocking IO. Typically, when the user application is using a
   socket BIO for writing, this will only result in a failed connection.
   However if some other BIO is used then it is likely that a segmentation
   fault will be triggered, thus enabling a potential DoS attack.

   This issue was reported to OpenSSL by Daniel Danner and Rainer Mueller.
   ([CVE-2015-0290])

   *Matt Caswell*

 * Segmentation fault in DTLSv1_listen fix

   The DTLSv1_listen function is intended to be stateless and processes the
   initial ClientHello from many peers. It is common for user code to loop
   over the call to DTLSv1_listen until a valid ClientHello is received with
   an associated cookie. A defect in the implementation of DTLSv1_listen means
   that state is preserved in the SSL object from one invocation to the next
   that can lead to a segmentation fault. Errors processing the initial
   ClientHello can trigger this scenario. An example of such an error could be
   that a DTLS1.0 only client is attempting to connect to a DTLS1.2 only
   server.

   This issue was reported to OpenSSL by Per Allansson.
   ([CVE-2015-0207])

   *Matt Caswell*

 * Segmentation fault in ASN1_TYPE_cmp fix

   The function ASN1_TYPE_cmp will crash with an invalid read if an attempt is
   made to compare ASN.1 boolean types. Since ASN1_TYPE_cmp is used to check
   certificate signature algorithm consistency this can be used to crash any
   certificate verification operation and exploited in a DoS attack. Any
   application which performs certificate verification is vulnerable including
   OpenSSL clients and servers which enable client authentication.
   ([CVE-2015-0286])

   *Stephen Henson*

 * Segmentation fault for invalid PSS parameters fix

   The signature verification routines will crash with a NULL pointer
   dereference if presented with an ASN.1 signature using the RSA PSS
   algorithm and invalid parameters. Since these routines are used to verify
   certificate signature algorithms this can be used to crash any
   certificate verification operation and exploited in a DoS attack. Any
   application which performs certificate verification is vulnerable including
   OpenSSL clients and servers which enable client authentication.

   This issue was was reported to OpenSSL by Brian Carpenter.
   ([CVE-2015-0208])

   *Stephen Henson*

 * ASN.1 structure reuse memory corruption fix

   Reusing a structure in ASN.1 parsing may allow an attacker to cause
   memory corruption via an invalid write. Such reuse is and has been
   strongly discouraged and is believed to be rare.

   Applications that parse structures containing CHOICE or ANY DEFINED BY
   components may be affected. Certificate parsing (d2i_X509 and related
   functions) are however not affected. OpenSSL clients and servers are
   not affected.
   ([CVE-2015-0287])

   *Stephen Henson*

 * PKCS7 NULL pointer dereferences fix

   The PKCS#7 parsing code does not handle missing outer ContentInfo
   correctly. An attacker can craft malformed ASN.1-encoded PKCS#7 blobs with
   missing content and trigger a NULL pointer dereference on parsing.

   Applications that verify PKCS#7 signatures, decrypt PKCS#7 data or
   otherwise parse PKCS#7 structures from untrusted sources are
   affected. OpenSSL clients and servers are not affected.

   This issue was reported to OpenSSL by Michal Zalewski (Google).
   ([CVE-2015-0289])

   *Emilia Käsper*

 * DoS via reachable assert in SSLv2 servers fix

   A malicious client can trigger an OPENSSL_assert (i.e., an abort) in
   servers that both support SSLv2 and enable export cipher suites by sending
   a specially crafted SSLv2 CLIENT-MASTER-KEY message.

   This issue was discovered by Sean Burford (Google) and Emilia Käsper
   (OpenSSL development team).
   ([CVE-2015-0293])

   *Emilia Käsper*

 * Empty CKE with client auth and DHE fix

   If client auth is used then a server can seg fault in the event of a DHE
   ciphersuite being selected and a zero length ClientKeyExchange message
   being sent by the client. This could be exploited in a DoS attack.
   ([CVE-2015-1787])

   *Matt Caswell*

 * Handshake with unseeded PRNG fix

   Under certain conditions an OpenSSL 1.0.2 client can complete a handshake
   with an unseeded PRNG. The conditions are:
   - The client is on a platform where the PRNG has not been seeded
   automatically, and the user has not seeded manually
   - A protocol specific client method version has been used (i.e. not
   SSL_client_methodv23)
   - A ciphersuite is used that does not require additional random data from
   the PRNG beyond the initial ClientHello client random (e.g. PSK-RC4-SHA).

   If the handshake succeeds then the client random that has been used will
   have been generated from a PRNG with insufficient entropy and therefore the
   output may be predictable.

   For example using the following command with an unseeded openssl will
   succeed on an unpatched platform:

   openssl s_client -psk 1a2b3c4d -tls1_2 -cipher PSK-RC4-SHA
   ([CVE-2015-0285])

   *Matt Caswell*

 * Use After Free following d2i_ECPrivatekey error fix

   A malformed EC private key file consumed via the d2i_ECPrivateKey function
   could cause a use after free condition. This, in turn, could cause a double
   free in several private key parsing functions (such as d2i_PrivateKey
   or EVP_PKCS82PKEY) and could lead to a DoS attack or memory corruption
   for applications that receive EC private keys from untrusted
   sources. This scenario is considered rare.

   This issue was discovered by the BoringSSL project and fixed in their
   commit 517073cd4b.
   ([CVE-2015-0209])

   *Matt Caswell*

 * X509_to_X509_REQ NULL pointer deref fix

   The function X509_to_X509_REQ will crash with a NULL pointer dereference if
   the certificate key is invalid. This function is rarely used in practice.

   This issue was discovered by Brian Carpenter.
   ([CVE-2015-0288])

   *Stephen Henson*

 * Removed the export ciphers from the DEFAULT ciphers

   *Kurt Roeckx*

### Changes between 1.0.1l and 1.0.2 [22 Jan 2015]

 * Facilitate "universal" ARM builds targeting range of ARM ISAs, e.g.
   ARMv5 through ARMv8, as opposite to "locking" it to single one.
   So far those who have to target multiple platforms would compromise
   and argue that binary targeting say ARMv5 would still execute on
   ARMv8. "Universal" build resolves this compromise by providing
   near-optimal performance even on newer platforms.

   *Andy Polyakov*

 * Accelerated NIST P-256 elliptic curve implementation for x86_64
   (other platforms pending).

   *Shay Gueron & Vlad Krasnov (Intel Corp), Andy Polyakov*

 * Add support for the SignedCertificateTimestampList certificate and
   OCSP response extensions from RFC6962.

   *Rob Stradling*

 * Fix ec_GFp_simple_points_make_affine (thus, EC_POINTs_mul etc.)
   for corner cases. (Certain input points at infinity could lead to
   bogus results, with non-infinity inputs mapped to infinity too.)

   *Bodo Moeller*

 * Initial support for PowerISA 2.0.7, first implemented in POWER8.
   This covers AES, SHA256/512 and GHASH. "Initial" means that most
   common cases are optimized and there still is room for further
   improvements. Vector Permutation AES for Altivec is also added.

   *Andy Polyakov*

 * Add support for little-endian ppc64 Linux target.

   *Marcelo Cerri (IBM)*

 * Initial support for AMRv8 ISA crypto extensions. This covers AES,
   SHA1, SHA256 and GHASH. "Initial" means that most common cases
   are optimized and there still is room for further improvements.
   Both 32- and 64-bit modes are supported.

   *Andy Polyakov, Ard Biesheuvel (Linaro)*

 * Improved ARMv7 NEON support.

   *Andy Polyakov*

 * Support for SPARC Architecture 2011 crypto extensions, first
   implemented in SPARC T4. This covers AES, DES, Camellia, SHA1,
   SHA256/512, MD5, GHASH and modular exponentiation.

   *Andy Polyakov, David Miller*

 * Accelerated modular exponentiation for Intel processors, a.k.a.
   RSAZ.

   *Shay Gueron & Vlad Krasnov (Intel Corp)*

 * Support for new and upcoming Intel processors, including AVX2,
   BMI and SHA ISA extensions. This includes additional "stitched"
   implementations, AESNI-SHA256 and GCM, and multi-buffer support
   for TLS encrypt.

   This work was sponsored by Intel Corp.

   *Andy Polyakov*

 * Support for DTLS 1.2. This adds two sets of DTLS methods: DTLS_*_method()
   supports both DTLS 1.2 and 1.0 and should use whatever version the peer
   supports and DTLSv1_2_*_method() which supports DTLS 1.2 only.

   *Steve Henson*

 * Use algorithm specific chains in SSL_CTX_use_certificate_chain_file():
   this fixes a limitation in previous versions of OpenSSL.

   *Steve Henson*

 * Extended RSA OAEP support via EVP_PKEY API. Options to specify digest,
   MGF1 digest and OAEP label.

   *Steve Henson*

 * Add EVP support for key wrapping algorithms, to avoid problems with
   existing code the flag EVP_CIPHER_CTX_WRAP_ALLOW has to be set in
   the EVP_CIPHER_CTX or an error is returned. Add AES and DES3 wrap
   algorithms and include tests cases.

   *Steve Henson*

 * Add functions to allocate and set the fields of an ECDSA_METHOD
   structure.

   *Douglas E. Engert, Steve Henson*

 * New functions OPENSSL_gmtime_diff and ASN1_TIME_diff to find the
   difference in days and seconds between two tm or ASN1_TIME structures.

   *Steve Henson*

 * Add -rev test option to s_server to just reverse order of characters
   received by client and send back to server. Also prints an abbreviated
   summary of the connection parameters.

   *Steve Henson*

 * New option -brief for s_client and s_server to print out a brief summary
   of connection parameters.

   *Steve Henson*

 * Add callbacks for arbitrary TLS extensions.

   *Trevor Perrin <trevp@trevp.net> and Ben Laurie*

 * New option -crl_download in several openssl utilities to download CRLs
   from CRLDP extension in certificates.

   *Steve Henson*

 * New options -CRL and -CRLform for s_client and s_server for CRLs.

   *Steve Henson*

 * New function X509_CRL_diff to generate a delta CRL from the difference
   of two full CRLs. Add support to "crl" utility.

   *Steve Henson*

 * New functions to set lookup_crls function and to retrieve
   X509_STORE from X509_STORE_CTX.

   *Steve Henson*

 * Print out deprecated issuer and subject unique ID fields in
   certificates.

   *Steve Henson*

 * Extend OCSP I/O functions so they can be used for simple general purpose
   HTTP as well as OCSP. New wrapper function which can be used to download
   CRLs using the OCSP API.

   *Steve Henson*

 * Delegate command line handling in s_client/s_server to SSL_CONF APIs.

   *Steve Henson*

 * `SSL_CONF*` functions. These provide a common framework for application
   configuration using configuration files or command lines.

   *Steve Henson*

 * SSL/TLS tracing code. This parses out SSL/TLS records using the
   message callback and prints the results. Needs compile time option
   "enable-ssl-trace". New options to s_client and s_server to enable
   tracing.

   *Steve Henson*

 * New ctrl and macro to retrieve supported points extensions.
   Print out extension in s_server and s_client.

   *Steve Henson*

 * New functions to retrieve certificate signature and signature
   OID NID.

   *Steve Henson*

 * Add functions to retrieve and manipulate the raw cipherlist sent by a
   client to OpenSSL.

   *Steve Henson*

 * New Suite B modes for TLS code. These use and enforce the requirements
   of RFC6460: restrict ciphersuites, only permit Suite B algorithms and
   only use Suite B curves. The Suite B modes can be set by using the
   strings "SUITEB128", "SUITEB192" or "SUITEB128ONLY" for the cipherstring.

   *Steve Henson*

 * New chain verification flags for Suite B levels of security. Check
   algorithms are acceptable when flags are set in X509_verify_cert.

   *Steve Henson*

 * Make tls1_check_chain return a set of flags indicating checks passed
   by a certificate chain. Add additional tests to handle client
   certificates: checks for matching certificate type and issuer name
   comparison.

   *Steve Henson*

 * If an attempt is made to use a signature algorithm not in the peer
   preference list abort the handshake. If client has no suitable
   signature algorithms in response to a certificate request do not
   use the certificate.

   *Steve Henson*

 * If server EC tmp key is not in client preference list abort handshake.

   *Steve Henson*

 * Add support for certificate stores in CERT structure. This makes it
   possible to have different stores per SSL structure or one store in
   the parent SSL_CTX. Include distinct stores for certificate chain
   verification and chain building. New ctrl SSL_CTRL_BUILD_CERT_CHAIN
   to build and store a certificate chain in CERT structure: returning
   an error if the chain cannot be built: this will allow applications
   to test if a chain is correctly configured.

   Note: if the CERT based stores are not set then the parent SSL_CTX
   store is used to retain compatibility with existing behaviour.

   *Steve Henson*

 * New function ssl_set_client_disabled to set a ciphersuite disabled
   mask based on the current session, check mask when sending client
   hello and checking the requested ciphersuite.

   *Steve Henson*

 * New ctrls to retrieve and set certificate types in a certificate
   request message. Print out received values in s_client. If certificate
   types is not set with custom values set sensible values based on
   supported signature algorithms.

   *Steve Henson*

 * Support for distinct client and server supported signature algorithms.

   *Steve Henson*

 * Add certificate callback. If set this is called whenever a certificate
   is required by client or server. An application can decide which
   certificate chain to present based on arbitrary criteria: for example
   supported signature algorithms. Add very simple example to s_server.
   This fixes many of the problems and restrictions of the existing client
   certificate callback: for example you can now clear an existing
   certificate and specify the whole chain.

   *Steve Henson*

 * Add new "valid_flags" field to CERT_PKEY structure which determines what
   the certificate can be used for (if anything). Set valid_flags field
   in new tls1_check_chain function. Simplify ssl_set_cert_masks which used
   to have similar checks in it.

   Add new "cert_flags" field to CERT structure and include a "strict mode".
   This enforces some TLS certificate requirements (such as only permitting
   certificate signature algorithms contained in the supported algorithms
   extension) which some implementations ignore: this option should be used
   with caution as it could cause interoperability issues.

   *Steve Henson*

 * Update and tidy signature algorithm extension processing. Work out
   shared signature algorithms based on preferences and peer algorithms
   and print them out in s_client and s_server. Abort handshake if no
   shared signature algorithms.

   *Steve Henson*

 * Add new functions to allow customised supported signature algorithms
   for SSL and SSL_CTX structures. Add options to s_client and s_server
   to support them.

   *Steve Henson*

 * New function SSL_certs_clear() to delete all references to certificates
   from an SSL structure. Before this once a certificate had been added
   it couldn't be removed.

   *Steve Henson*

 * Integrate hostname, email address and IP address checking with certificate
   verification. New verify options supporting checking in openssl utility.

   *Steve Henson*

 * Fixes and wildcard matching support to hostname and email checking
   functions. Add manual page.

   *Florian Weimer (Red Hat Product Security Team)*

 * New functions to check a hostname email or IP address against a
   certificate. Add options x509 utility to print results of checks against
   a certificate.

   *Steve Henson*

 * Fix OCSP checking.

   *Rob Stradling <rob.stradling@comodo.com> and Ben Laurie*

 * Initial experimental support for explicitly trusted non-root CAs.
   OpenSSL still tries to build a complete chain to a root but if an
   intermediate CA has a trust setting included that is used. The first
   setting is used: whether to trust (e.g., -addtrust option to the x509
   utility) or reject.

   *Steve Henson*

 * Add -trusted_first option which attempts to find certificates in the
   trusted store even if an untrusted chain is also supplied.

   *Steve Henson*

 * MIPS assembly pack updates: support for MIPS32r2 and SmartMIPS ASE,
   platform support for Linux and Android.

   *Andy Polyakov*

 * Support for linux-x32, ILP32 environment in x86_64 framework.

   *Andy Polyakov*

 * Experimental multi-implementation support for FIPS capable OpenSSL.
   When in FIPS mode the approved implementations are used as normal,
   when not in FIPS mode the internal unapproved versions are used instead.
   This means that the FIPS capable OpenSSL isn't forced to use the
   (often lower performance) FIPS implementations outside FIPS mode.

   *Steve Henson*

 * Transparently support X9.42 DH parameters when calling
   PEM_read_bio_DHparameters. This means existing applications can handle
   the new parameter format automatically.

   *Steve Henson*

 * Initial experimental support for X9.42 DH parameter format: mainly
   to support use of 'q' parameter for RFC5114 parameters.

   *Steve Henson*

 * Add DH parameters from RFC5114 including test data to dhtest.

   *Steve Henson*

 * Support for automatic EC temporary key parameter selection. If enabled
   the most preferred EC parameters are automatically used instead of
   hardcoded fixed parameters. Now a server just has to call:
   SSL_CTX_set_ecdh_auto(ctx, 1) and the server will automatically
   support ECDH and use the most appropriate parameters.

   *Steve Henson*

 * Enhance and tidy EC curve and point format TLS extension code. Use
   static structures instead of allocation if default values are used.
   New ctrls to set curves we wish to support and to retrieve shared curves.
   Print out shared curves in s_server. New options to s_server and s_client
   to set list of supported curves.

   *Steve Henson*

 * New ctrls to retrieve supported signature algorithms and
   supported curve values as an array of NIDs. Extend openssl utility
   to print out received values.

   *Steve Henson*

 * Add new APIs EC_curve_nist2nid and EC_curve_nid2nist which convert
   between NIDs and the more common NIST names such as "P-256". Enhance
   ecparam utility and ECC method to recognise the NIST names for curves.

   *Steve Henson*

 * Enhance SSL/TLS certificate chain handling to support different
   chains for each certificate instead of one chain in the parent SSL_CTX.

   *Steve Henson*

 * Support for fixed DH ciphersuite client authentication: where both
   server and client use DH certificates with common parameters.

   *Steve Henson*

 * Support for fixed DH ciphersuites: those requiring DH server
   certificates.

   *Steve Henson*

 * New function i2d_re_X509_tbs for re-encoding the TBS portion of
   the certificate.
   Note: Related 1.0.2-beta specific macros X509_get_cert_info,
   X509_CINF_set_modified, X509_CINF_get_issuer, X509_CINF_get_extensions and
   X509_CINF_get_signature were reverted post internal team review.

OpenSSL 1.0.1
-------------

### Changes between 1.0.1t and 1.0.1u [22 Sep 2016]

 * OCSP Status Request extension unbounded memory growth

   A malicious client can send an excessively large OCSP Status Request
   extension. If that client continually requests renegotiation, sending a
   large OCSP Status Request extension each time, then there will be unbounded
   memory growth on the server. This will eventually lead to a Denial Of
   Service attack through memory exhaustion. Servers with a default
   configuration are vulnerable even if they do not support OCSP. Builds using
   the "no-ocsp" build time option are not affected.

   This issue was reported to OpenSSL by Shi Lei (Gear Team, Qihoo 360 Inc.)
   ([CVE-2016-6304])

   *Matt Caswell*

 * In order to mitigate the SWEET32 attack, the DES ciphers were moved from
   HIGH to MEDIUM.

   This issue was reported to OpenSSL Karthikeyan Bhargavan and Gaetan
   Leurent (INRIA)
   ([CVE-2016-2183])

   *Rich Salz*

 * OOB write in MDC2_Update()

   An overflow can occur in MDC2_Update() either if called directly or
   through the EVP_DigestUpdate() function using MDC2. If an attacker
   is able to supply very large amounts of input data after a previous
   call to EVP_EncryptUpdate() with a partial block then a length check
   can overflow resulting in a heap corruption.

   The amount of data needed is comparable to SIZE_MAX which is impractical
   on most platforms.

   This issue was reported to OpenSSL by Shi Lei (Gear Team, Qihoo 360 Inc.)
   ([CVE-2016-6303])

   *Stephen Henson*

 * Malformed SHA512 ticket DoS

   If a server uses SHA512 for TLS session ticket HMAC it is vulnerable to a
   DoS attack where a malformed ticket will result in an OOB read which will
   ultimately crash.

   The use of SHA512 in TLS session tickets is comparatively rare as it requires
   a custom server callback and ticket lookup mechanism.

   This issue was reported to OpenSSL by Shi Lei (Gear Team, Qihoo 360 Inc.)
   ([CVE-2016-6302])

   *Stephen Henson*

 * OOB write in BN_bn2dec()

   The function BN_bn2dec() does not check the return value of BN_div_word().
   This can cause an OOB write if an application uses this function with an
   overly large BIGNUM. This could be a problem if an overly large certificate
   or CRL is printed out from an untrusted source. TLS is not affected because
   record limits will reject an oversized certificate before it is parsed.

   This issue was reported to OpenSSL by Shi Lei (Gear Team, Qihoo 360 Inc.)
   ([CVE-2016-2182])

   *Stephen Henson*

 * OOB read in TS_OBJ_print_bio()

   The function TS_OBJ_print_bio() misuses OBJ_obj2txt(): the return value is
   the total length the OID text representation would use and not the amount
   of data written. This will result in OOB reads when large OIDs are
   presented.

   This issue was reported to OpenSSL by Shi Lei (Gear Team, Qihoo 360 Inc.)
   ([CVE-2016-2180])

   *Stephen Henson*

 * Pointer arithmetic undefined behaviour

   Avoid some undefined pointer arithmetic

   A common idiom in the codebase is to check limits in the following manner:
   "p + len > limit"

   Where "p" points to some malloc'd data of SIZE bytes and
   limit == p + SIZE

   "len" here could be from some externally supplied data (e.g. from a TLS
   message).

   The rules of C pointer arithmetic are such that "p + len" is only well
   defined where len <= SIZE. Therefore, the above idiom is actually
   undefined behaviour.

   For example this could cause problems if some malloc implementation
   provides an address for "p" such that "p + len" actually overflows for
   values of len that are too big and therefore p + len < limit.

   This issue was reported to OpenSSL by Guido Vranken
   ([CVE-2016-2177])

   *Matt Caswell*

 * Constant time flag not preserved in DSA signing

   Operations in the DSA signing algorithm should run in constant time in
   order to avoid side channel attacks. A flaw in the OpenSSL DSA
   implementation means that a non-constant time codepath is followed for
   certain operations. This has been demonstrated through a cache-timing
   attack to be sufficient for an attacker to recover the private DSA key.

   This issue was reported by César Pereida (Aalto University), Billy Brumley
   (Tampere University of Technology), and Yuval Yarom (The University of
   Adelaide and NICTA).
   ([CVE-2016-2178])

   *César Pereida*

 * DTLS buffered message DoS

   In a DTLS connection where handshake messages are delivered out-of-order
   those messages that OpenSSL is not yet ready to process will be buffered
   for later use. Under certain circumstances, a flaw in the logic means that
   those messages do not get removed from the buffer even though the handshake
   has been completed. An attacker could force up to approx. 15 messages to
   remain in the buffer when they are no longer required. These messages will
   be cleared when the DTLS connection is closed. The default maximum size for
   a message is 100k. Therefore, the attacker could force an additional 1500k
   to be consumed per connection. By opening many simultaneous connections an
   attacker could cause a DoS attack through memory exhaustion.

   This issue was reported to OpenSSL by Quan Luo.
   ([CVE-2016-2179])

   *Matt Caswell*

 * DTLS replay protection DoS

   A flaw in the DTLS replay attack protection mechanism means that records
   that arrive for future epochs update the replay protection "window" before
   the MAC for the record has been validated. This could be exploited by an
   attacker by sending a record for the next epoch (which does not have to
   decrypt or have a valid MAC), with a very large sequence number. This means
   that all subsequent legitimate packets are dropped causing a denial of
   service for a specific DTLS connection.

   This issue was reported to OpenSSL by the OCAP audit team.
   ([CVE-2016-2181])

   *Matt Caswell*

 * Certificate message OOB reads

   In OpenSSL 1.0.2 and earlier some missing message length checks can result
   in OOB reads of up to 2 bytes beyond an allocated buffer. There is a
   theoretical DoS risk but this has not been observed in practice on common
   platforms.

   The messages affected are client certificate, client certificate request
   and server certificate. As a result the attack can only be performed
   against a client or a server which enables client authentication.

   This issue was reported to OpenSSL by Shi Lei (Gear Team, Qihoo 360 Inc.)
   ([CVE-2016-6306])

   *Stephen Henson*

### Changes between 1.0.1s and 1.0.1t [3 May 2016]

 * Prevent padding oracle in AES-NI CBC MAC check

   A MITM attacker can use a padding oracle attack to decrypt traffic
   when the connection uses an AES CBC cipher and the server support
   AES-NI.

   This issue was introduced as part of the fix for Lucky 13 padding
   attack ([CVE-2013-0169]). The padding check was rewritten to be in
   constant time by making sure that always the same bytes are read and
   compared against either the MAC or padding bytes. But it no longer
   checked that there was enough data to have both the MAC and padding
   bytes.

   This issue was reported by Juraj Somorovsky using TLS-Attacker.
   ([CVE-2016-2107])

   *Kurt Roeckx*

 * Fix EVP_EncodeUpdate overflow

   An overflow can occur in the EVP_EncodeUpdate() function which is used for
   Base64 encoding of binary data. If an attacker is able to supply very large
   amounts of input data then a length check can overflow resulting in a heap
   corruption.

   Internally to OpenSSL the EVP_EncodeUpdate() function is primarily used by
   the `PEM_write_bio*` family of functions. These are mainly used within the
   OpenSSL command line applications, so any application which processes data
   from an untrusted source and outputs it as a PEM file should be considered
   vulnerable to this issue. User applications that call these APIs directly
   with large amounts of untrusted data may also be vulnerable.

   This issue was reported by Guido Vranken.
   ([CVE-2016-2105])

   *Matt Caswell*

 * Fix EVP_EncryptUpdate overflow

   An overflow can occur in the EVP_EncryptUpdate() function. If an attacker
   is able to supply very large amounts of input data after a previous call to
   EVP_EncryptUpdate() with a partial block then a length check can overflow
   resulting in a heap corruption. Following an analysis of all OpenSSL
   internal usage of the EVP_EncryptUpdate() function all usage is one of two
   forms. The first form is where the EVP_EncryptUpdate() call is known to be
   the first called function after an EVP_EncryptInit(), and therefore that
   specific call must be safe. The second form is where the length passed to
   EVP_EncryptUpdate() can be seen from the code to be some small value and
   therefore there is no possibility of an overflow. Since all instances are
   one of these two forms, it is believed that there can be no overflows in
   internal code due to this problem. It should be noted that
   EVP_DecryptUpdate() can call EVP_EncryptUpdate() in certain code paths.
   Also EVP_CipherUpdate() is a synonym for EVP_EncryptUpdate(). All instances
   of these calls have also been analysed too and it is believed there are no
   instances in internal usage where an overflow could occur.

   This issue was reported by Guido Vranken.
   ([CVE-2016-2106])

   *Matt Caswell*

 * Prevent ASN.1 BIO excessive memory allocation

   When ASN.1 data is read from a BIO using functions such as d2i_CMS_bio()
   a short invalid encoding can casuse allocation of large amounts of memory
   potentially consuming excessive resources or exhausting memory.

   Any application parsing untrusted data through d2i BIO functions is
   affected. The memory based functions such as d2i_X509() are *not* affected.
   Since the memory based functions are used by the TLS library, TLS
   applications are not affected.

   This issue was reported by Brian Carpenter.
   ([CVE-2016-2109])

   *Stephen Henson*

 * EBCDIC overread

   ASN1 Strings that are over 1024 bytes can cause an overread in applications
   using the X509_NAME_oneline() function on EBCDIC systems. This could result
   in arbitrary stack data being returned in the buffer.

   This issue was reported by Guido Vranken.
   ([CVE-2016-2176])

   *Matt Caswell*

 * Modify behavior of ALPN to invoke callback after SNI/servername
   callback, such that updates to the SSL_CTX affect ALPN.

   *Todd Short*

 * Remove LOW from the DEFAULT cipher list.  This removes singles DES from the
   default.

   *Kurt Roeckx*

 * Only remove the SSLv2 methods with the no-ssl2-method option. When the
   methods are enabled and ssl2 is disabled the methods return NULL.

   *Kurt Roeckx*

### Changes between 1.0.1r and 1.0.1s [1 Mar 2016]

* Disable weak ciphers in SSLv3 and up in default builds of OpenSSL.
  Builds that are not configured with "enable-weak-ssl-ciphers" will not
  provide any "EXPORT" or "LOW" strength ciphers.

  *Viktor Dukhovni*

* Disable SSLv2 default build, default negotiation and weak ciphers.  SSLv2
  is by default disabled at build-time.  Builds that are not configured with
  "enable-ssl2" will not support SSLv2.  Even if "enable-ssl2" is used,
  users who want to negotiate SSLv2 via the version-flexible SSLv23_method()
  will need to explicitly call either of:

      SSL_CTX_clear_options(ctx, SSL_OP_NO_SSLv2);
  or
      SSL_clear_options(ssl, SSL_OP_NO_SSLv2);

  as appropriate.  Even if either of those is used, or the application
  explicitly uses the version-specific SSLv2_method() or its client and
  server variants, SSLv2 ciphers vulnerable to exhaustive search key
  recovery have been removed.  Specifically, the SSLv2 40-bit EXPORT
  ciphers, and SSLv2 56-bit DES are no longer available.
  ([CVE-2016-0800])

  *Viktor Dukhovni*

 * Fix a double-free in DSA code

   A double free bug was discovered when OpenSSL parses malformed DSA private
   keys and could lead to a DoS attack or memory corruption for applications
   that receive DSA private keys from untrusted sources.  This scenario is
   considered rare.

   This issue was reported to OpenSSL by Adam Langley(Google/BoringSSL) using
   libFuzzer.
   ([CVE-2016-0705])

   *Stephen Henson*

 * Disable SRP fake user seed to address a server memory leak.

   Add a new method SRP_VBASE_get1_by_user that handles the seed properly.

   SRP_VBASE_get_by_user had inconsistent memory management behaviour.
   In order to fix an unavoidable memory leak, SRP_VBASE_get_by_user
   was changed to ignore the "fake user" SRP seed, even if the seed
   is configured.

   Users should use SRP_VBASE_get1_by_user instead. Note that in
   SRP_VBASE_get1_by_user, caller must free the returned value. Note
   also that even though configuring the SRP seed attempts to hide
   invalid usernames by continuing the handshake with fake
   credentials, this behaviour is not constant time and no strong
   guarantees are made that the handshake is indistinguishable from
   that of a valid user.
   ([CVE-2016-0798])

   *Emilia Käsper*

 * Fix BN_hex2bn/BN_dec2bn NULL pointer deref/heap corruption

   In the BN_hex2bn function the number of hex digits is calculated using an
   int value `i`. Later `bn_expand` is called with a value of `i * 4`. For
   large values of `i` this can result in `bn_expand` not allocating any
   memory because `i * 4` is negative. This can leave the internal BIGNUM data
   field as NULL leading to a subsequent NULL ptr deref. For very large values
   of `i`, the calculation `i * 4` could be a positive value smaller than `i`.
   In this case memory is allocated to the internal BIGNUM data field, but it
   is insufficiently sized leading to heap corruption. A similar issue exists
   in BN_dec2bn. This could have security consequences if BN_hex2bn/BN_dec2bn
   is ever called by user applications with very large untrusted hex/dec data.
   This is anticipated to be a rare occurrence.

   All OpenSSL internal usage of these functions use data that is not expected
   to be untrusted, e.g. config file data or application command line
   arguments. If user developed applications generate config file data based
   on untrusted data then it is possible that this could also lead to security
   consequences. This is also anticipated to be rare.

   This issue was reported to OpenSSL by Guido Vranken.
   ([CVE-2016-0797])

   *Matt Caswell*

 * Fix memory issues in `BIO_*printf` functions

   The internal `fmtstr` function used in processing a "%s" format string in
   the `BIO_*printf` functions could overflow while calculating the length of a
   string and cause an OOB read when printing very long strings.

   Additionally the internal `doapr_outch` function can attempt to write to an
   OOB memory location (at an offset from the NULL pointer) in the event of a
   memory allocation failure. In 1.0.2 and below this could be caused where
   the size of a buffer to be allocated is greater than INT_MAX. E.g. this
   could be in processing a very long "%s" format string. Memory leaks can
   also occur.

   The first issue may mask the second issue dependent on compiler behaviour.
   These problems could enable attacks where large amounts of untrusted data
   is passed to the `BIO_*printf` functions. If applications use these functions
   in this way then they could be vulnerable. OpenSSL itself uses these
   functions when printing out human-readable dumps of ASN.1 data. Therefore
   applications that print this data could be vulnerable if the data is from
   untrusted sources. OpenSSL command line applications could also be
   vulnerable where they print out ASN.1 data, or if untrusted data is passed
   as command line arguments.

   Libssl is not considered directly vulnerable. Additionally certificates etc
   received via remote connections via libssl are also unlikely to be able to
   trigger these issues because of message size limits enforced within libssl.

   This issue was reported to OpenSSL Guido Vranken.
   ([CVE-2016-0799])

   *Matt Caswell*

 * Side channel attack on modular exponentiation

   A side-channel attack was found which makes use of cache-bank conflicts on
   the Intel Sandy-Bridge microarchitecture which could lead to the recovery
   of RSA keys.  The ability to exploit this issue is limited as it relies on
   an attacker who has control of code in a thread running on the same
   hyper-threaded core as the victim thread which is performing decryptions.

   This issue was reported to OpenSSL by Yuval Yarom, The University of
   Adelaide and NICTA, Daniel Genkin, Technion and Tel Aviv University, and
   Nadia Heninger, University of Pennsylvania with more information at
   <http://cachebleed.info>.
   ([CVE-2016-0702])

   *Andy Polyakov*

 * Change the req command to generate a 2048-bit RSA/DSA key by default,
   if no keysize is specified with default_bits. This fixes an
   omission in an earlier change that changed all RSA/DSA key generation
   commands to use 2048 bits by default.

   *Emilia Käsper*

### Changes between 1.0.1q and 1.0.1r [28 Jan 2016]

 * Protection for DH small subgroup attacks

   As a precautionary measure the SSL_OP_SINGLE_DH_USE option has been
   switched on by default and cannot be disabled. This could have some
   performance impact.

   *Matt Caswell*

 * SSLv2 doesn't block disabled ciphers

   A malicious client can negotiate SSLv2 ciphers that have been disabled on
   the server and complete SSLv2 handshakes even if all SSLv2 ciphers have
   been disabled, provided that the SSLv2 protocol was not also disabled via
   SSL_OP_NO_SSLv2.

   This issue was reported to OpenSSL on 26th December 2015 by Nimrod Aviram
   and Sebastian Schinzel.
   ([CVE-2015-3197])

   *Viktor Dukhovni*

 * Reject DH handshakes with parameters shorter than 1024 bits.

   *Kurt Roeckx*

### Changes between 1.0.1p and 1.0.1q [3 Dec 2015]

 * Certificate verify crash with missing PSS parameter

   The signature verification routines will crash with a NULL pointer
   dereference if presented with an ASN.1 signature using the RSA PSS
   algorithm and absent mask generation function parameter. Since these
   routines are used to verify certificate signature algorithms this can be
   used to crash any certificate verification operation and exploited in a
   DoS attack. Any application which performs certificate verification is
   vulnerable including OpenSSL clients and servers which enable client
   authentication.

   This issue was reported to OpenSSL by Loïc Jonas Etienne (Qnective AG).
   ([CVE-2015-3194])

   *Stephen Henson*

 * X509_ATTRIBUTE memory leak

   When presented with a malformed X509_ATTRIBUTE structure OpenSSL will leak
   memory. This structure is used by the PKCS#7 and CMS routines so any
   application which reads PKCS#7 or CMS data from untrusted sources is
   affected. SSL/TLS is not affected.

   This issue was reported to OpenSSL by Adam Langley (Google/BoringSSL) using
   libFuzzer.
   ([CVE-2015-3195])

   *Stephen Henson*

 * Rewrite EVP_DecodeUpdate (base64 decoding) to fix several bugs.
   This changes the decoding behaviour for some invalid messages,
   though the change is mostly in the more lenient direction, and
   legacy behaviour is preserved as much as possible.

   *Emilia Käsper*

 * In DSA_generate_parameters_ex, if the provided seed is too short,
   use a random seed, as already documented.

   *Rich Salz and Ismo Puustinen <ismo.puustinen@intel.com>*

### Changes between 1.0.1o and 1.0.1p [9 Jul 2015]

 * Alternate chains certificate forgery

   During certificate verfification, OpenSSL will attempt to find an
   alternative certificate chain if the first attempt to build such a chain
   fails. An error in the implementation of this logic can mean that an
   attacker could cause certain checks on untrusted certificates to be
   bypassed, such as the CA flag, enabling them to use a valid leaf
   certificate to act as a CA and "issue" an invalid certificate.

   This issue was reported to OpenSSL by Adam Langley/David Benjamin
   (Google/BoringSSL).
   ([CVE-2015-1793])

   *Matt Caswell*

 * Race condition handling PSK identify hint

   If PSK identity hints are received by a multi-threaded client then
   the values are wrongly updated in the parent SSL_CTX structure. This can
   result in a race condition potentially leading to a double free of the
   identify hint data.
   ([CVE-2015-3196])

   *Stephen Henson*

### Changes between 1.0.1n and 1.0.1o [12 Jun 2015]

 * Fix HMAC ABI incompatibility. The previous version introduced an ABI
   incompatibility in the handling of HMAC. The previous ABI has now been
   restored.

### Changes between 1.0.1m and 1.0.1n [11 Jun 2015]

 * Malformed ECParameters causes infinite loop

   When processing an ECParameters structure OpenSSL enters an infinite loop
   if the curve specified is over a specially malformed binary polynomial
   field.

   This can be used to perform denial of service against any
   system which processes public keys, certificate requests or
   certificates.  This includes TLS clients and TLS servers with
   client authentication enabled.

   This issue was reported to OpenSSL by Joseph Barr-Pixton.
   ([CVE-2015-1788])

   *Andy Polyakov*

 * Exploitable out-of-bounds read in X509_cmp_time

   X509_cmp_time does not properly check the length of the ASN1_TIME
   string and can read a few bytes out of bounds. In addition,
   X509_cmp_time accepts an arbitrary number of fractional seconds in the
   time string.

   An attacker can use this to craft malformed certificates and CRLs of
   various sizes and potentially cause a segmentation fault, resulting in
   a DoS on applications that verify certificates or CRLs. TLS clients
   that verify CRLs are affected. TLS clients and servers with client
   authentication enabled may be affected if they use custom verification
   callbacks.

   This issue was reported to OpenSSL by Robert Swiecki (Google), and
   independently by Hanno Böck.
   ([CVE-2015-1789])

   *Emilia Käsper*

 * PKCS7 crash with missing EnvelopedContent

   The PKCS#7 parsing code does not handle missing inner EncryptedContent
   correctly. An attacker can craft malformed ASN.1-encoded PKCS#7 blobs
   with missing content and trigger a NULL pointer dereference on parsing.

   Applications that decrypt PKCS#7 data or otherwise parse PKCS#7
   structures from untrusted sources are affected. OpenSSL clients and
   servers are not affected.

   This issue was reported to OpenSSL by Michal Zalewski (Google).
   ([CVE-2015-1790])

   *Emilia Käsper*

 * CMS verify infinite loop with unknown hash function

   When verifying a signedData message the CMS code can enter an infinite loop
   if presented with an unknown hash function OID. This can be used to perform
   denial of service against any system which verifies signedData messages using
   the CMS code.
   This issue was reported to OpenSSL by Johannes Bauer.
   ([CVE-2015-1792])

   *Stephen Henson*

 * Race condition handling NewSessionTicket

   If a NewSessionTicket is received by a multi-threaded client when attempting to
   reuse a previous ticket then a race condition can occur potentially leading to
   a double free of the ticket data.
   ([CVE-2015-1791])

   *Matt Caswell*

 * Reject DH handshakes with parameters shorter than 768 bits.

   *Kurt Roeckx and Emilia Kasper*

 * dhparam: generate 2048-bit parameters by default.

   *Kurt Roeckx and Emilia Kasper*

### Changes between 1.0.1l and 1.0.1m [19 Mar 2015]

 * Segmentation fault in ASN1_TYPE_cmp fix

   The function ASN1_TYPE_cmp will crash with an invalid read if an attempt is
   made to compare ASN.1 boolean types. Since ASN1_TYPE_cmp is used to check
   certificate signature algorithm consistency this can be used to crash any
   certificate verification operation and exploited in a DoS attack. Any
   application which performs certificate verification is vulnerable including
   OpenSSL clients and servers which enable client authentication.
   ([CVE-2015-0286])

   *Stephen Henson*

 * ASN.1 structure reuse memory corruption fix

   Reusing a structure in ASN.1 parsing may allow an attacker to cause
   memory corruption via an invalid write. Such reuse is and has been
   strongly discouraged and is believed to be rare.

   Applications that parse structures containing CHOICE or ANY DEFINED BY
   components may be affected. Certificate parsing (d2i_X509 and related
   functions) are however not affected. OpenSSL clients and servers are
   not affected.
   ([CVE-2015-0287])

   *Stephen Henson*

 * PKCS7 NULL pointer dereferences fix

   The PKCS#7 parsing code does not handle missing outer ContentInfo
   correctly. An attacker can craft malformed ASN.1-encoded PKCS#7 blobs with
   missing content and trigger a NULL pointer dereference on parsing.

   Applications that verify PKCS#7 signatures, decrypt PKCS#7 data or
   otherwise parse PKCS#7 structures from untrusted sources are
   affected. OpenSSL clients and servers are not affected.

   This issue was reported to OpenSSL by Michal Zalewski (Google).
   ([CVE-2015-0289])

   *Emilia Käsper*

 * DoS via reachable assert in SSLv2 servers fix

   A malicious client can trigger an OPENSSL_assert (i.e., an abort) in
   servers that both support SSLv2 and enable export cipher suites by sending
   a specially crafted SSLv2 CLIENT-MASTER-KEY message.

   This issue was discovered by Sean Burford (Google) and Emilia Käsper
   (OpenSSL development team).
   ([CVE-2015-0293])

   *Emilia Käsper*

 * Use After Free following d2i_ECPrivatekey error fix

   A malformed EC private key file consumed via the d2i_ECPrivateKey function
   could cause a use after free condition. This, in turn, could cause a double
   free in several private key parsing functions (such as d2i_PrivateKey
   or EVP_PKCS82PKEY) and could lead to a DoS attack or memory corruption
   for applications that receive EC private keys from untrusted
   sources. This scenario is considered rare.

   This issue was discovered by the BoringSSL project and fixed in their
   commit 517073cd4b.
   ([CVE-2015-0209])

   *Matt Caswell*

 * X509_to_X509_REQ NULL pointer deref fix

   The function X509_to_X509_REQ will crash with a NULL pointer dereference if
   the certificate key is invalid. This function is rarely used in practice.

   This issue was discovered by Brian Carpenter.
   ([CVE-2015-0288])

   *Stephen Henson*

 * Removed the export ciphers from the DEFAULT ciphers

   *Kurt Roeckx*

### Changes between 1.0.1k and 1.0.1l [15 Jan 2015]

 * Build fixes for the Windows and OpenVMS platforms

   *Matt Caswell and Richard Levitte*

### Changes between 1.0.1j and 1.0.1k [8 Jan 2015]

 * Fix DTLS segmentation fault in dtls1_get_record. A carefully crafted DTLS
   message can cause a segmentation fault in OpenSSL due to a NULL pointer
   dereference. This could lead to a Denial Of Service attack. Thanks to
   Markus Stenberg of Cisco Systems, Inc. for reporting this issue.
   ([CVE-2014-3571])

   *Steve Henson*

 * Fix DTLS memory leak in dtls1_buffer_record. A memory leak can occur in the
   dtls1_buffer_record function under certain conditions. In particular this
   could occur if an attacker sent repeated DTLS records with the same
   sequence number but for the next epoch. The memory leak could be exploited
   by an attacker in a Denial of Service attack through memory exhaustion.
   Thanks to Chris Mueller for reporting this issue.
   ([CVE-2015-0206])

   *Matt Caswell*

 * Fix issue where no-ssl3 configuration sets method to NULL. When openssl is
   built with the no-ssl3 option and a SSL v3 ClientHello is received the ssl
   method would be set to NULL which could later result in a NULL pointer
   dereference. Thanks to Frank Schmirler for reporting this issue.
   ([CVE-2014-3569])

   *Kurt Roeckx*

 * Abort handshake if server key exchange message is omitted for ephemeral
   ECDH ciphersuites.

   Thanks to Karthikeyan Bhargavan of the PROSECCO team at INRIA for
   reporting this issue.
   ([CVE-2014-3572])

   *Steve Henson*

 * Remove non-export ephemeral RSA code on client and server. This code
   violated the TLS standard by allowing the use of temporary RSA keys in
   non-export ciphersuites and could be used by a server to effectively
   downgrade the RSA key length used to a value smaller than the server
   certificate. Thanks for Karthikeyan Bhargavan of the PROSECCO team at
   INRIA or reporting this issue.
   ([CVE-2015-0204])

   *Steve Henson*

 * Fixed issue where DH client certificates are accepted without verification.
   An OpenSSL server will accept a DH certificate for client authentication
   without the certificate verify message. This effectively allows a client to
   authenticate without the use of a private key. This only affects servers
   which trust a client certificate authority which issues certificates
   containing DH keys: these are extremely rare and hardly ever encountered.
   Thanks for Karthikeyan Bhargavan of the PROSECCO team at INRIA or reporting
   this issue.
   ([CVE-2015-0205])

   *Steve Henson*

 * Ensure that the session ID context of an SSL is updated when its
   SSL_CTX is updated via SSL_set_SSL_CTX.

   The session ID context is typically set from the parent SSL_CTX,
   and can vary with the CTX.

   *Adam Langley*

 * Fix various certificate fingerprint issues.

   By using non-DER or invalid encodings outside the signed portion of a
   certificate the fingerprint can be changed without breaking the signature.
   Although no details of the signed portion of the certificate can be changed
   this can cause problems with some applications: e.g. those using the
   certificate fingerprint for blacklists.

   1. Reject signatures with non zero unused bits.

   If the BIT STRING containing the signature has non zero unused bits reject
   the signature. All current signature algorithms require zero unused bits.

   2. Check certificate algorithm consistency.

   Check the AlgorithmIdentifier inside TBS matches the one in the
   certificate signature. NB: this will result in signature failure
   errors for some broken certificates.

   Thanks to Konrad Kraszewski from Google for reporting this issue.

   3. Check DSA/ECDSA signatures use DER.

   Re-encode DSA/ECDSA signatures and compare with the original received
   signature. Return an error if there is a mismatch.

   This will reject various cases including garbage after signature
   (thanks to Antti Karjalainen and Tuomo Untinen from the Codenomicon CROSS
   program for discovering this case) and use of BER or invalid ASN.1 INTEGERs
   (negative or with leading zeroes).

   Further analysis was conducted and fixes were developed by Stephen Henson
   of the OpenSSL core team.

   ([CVE-2014-8275])

   *Steve Henson*

 * Correct Bignum squaring. Bignum squaring (BN_sqr) may produce incorrect
   results on some platforms, including x86_64. This bug occurs at random
   with a very low probability, and is not known to be exploitable in any
   way, though its exact impact is difficult to determine. Thanks to Pieter
   Wuille (Blockstream) who reported this issue and also suggested an initial
   fix. Further analysis was conducted by the OpenSSL development team and
   Adam Langley of Google. The final fix was developed by Andy Polyakov of
   the OpenSSL core team.
   ([CVE-2014-3570])

   *Andy Polyakov*

 * Do not resume sessions on the server if the negotiated protocol
   version does not match the session's version. Resuming with a different
   version, while not strictly forbidden by the RFC, is of questionable
   sanity and breaks all known clients.

   *David Benjamin, Emilia Käsper*

 * Tighten handling of the ChangeCipherSpec (CCS) message: reject
   early CCS messages during renegotiation. (Note that because
   renegotiation is encrypted, this early CCS was not exploitable.)

   *Emilia Käsper*

 * Tighten client-side session ticket handling during renegotiation:
   ensure that the client only accepts a session ticket if the server sends
   the extension anew in the ServerHello. Previously, a TLS client would
   reuse the old extension state and thus accept a session ticket if one was
   announced in the initial ServerHello.

   Similarly, ensure that the client requires a session ticket if one
   was advertised in the ServerHello. Previously, a TLS client would
   ignore a missing NewSessionTicket message.

   *Emilia Käsper*

### Changes between 1.0.1i and 1.0.1j [15 Oct 2014]

 * SRTP Memory Leak.

   A flaw in the DTLS SRTP extension parsing code allows an attacker, who
   sends a carefully crafted handshake message, to cause OpenSSL to fail
   to free up to 64k of memory causing a memory leak. This could be
   exploited in a Denial Of Service attack. This issue affects OpenSSL
   1.0.1 server implementations for both SSL/TLS and DTLS regardless of
   whether SRTP is used or configured. Implementations of OpenSSL that
   have been compiled with OPENSSL_NO_SRTP defined are not affected.

   The fix was developed by the OpenSSL team.
   ([CVE-2014-3513])

   *OpenSSL team*

 * Session Ticket Memory Leak.

   When an OpenSSL SSL/TLS/DTLS server receives a session ticket the
   integrity of that ticket is first verified. In the event of a session
   ticket integrity check failing, OpenSSL will fail to free memory
   causing a memory leak. By sending a large number of invalid session
   tickets an attacker could exploit this issue in a Denial Of Service
   attack.
   ([CVE-2014-3567])

   *Steve Henson*

 * Build option no-ssl3 is incomplete.

   When OpenSSL is configured with "no-ssl3" as a build option, servers
   could accept and complete an SSL 3.0 handshake, and clients could be
   configured to send them.
   ([CVE-2014-3568])

   *Akamai and the OpenSSL team*

 * Add support for TLS_FALLBACK_SCSV.
   Client applications doing fallback retries should call
   SSL_set_mode(s, SSL_MODE_SEND_FALLBACK_SCSV).
   ([CVE-2014-3566])

   *Adam Langley, Bodo Moeller*

 * Add additional DigestInfo checks.

   Re-encode DigestInto in DER and check against the original when
   verifying RSA signature: this will reject any improperly encoded
   DigestInfo structures.

   Note: this is a precautionary measure and no attacks are currently known.

   *Steve Henson*

### Changes between 1.0.1h and 1.0.1i [6 Aug 2014]

 * Fix SRP buffer overrun vulnerability. Invalid parameters passed to the
   SRP code can be overrun an internal buffer. Add sanity check that
   g, A, B < N to SRP code.

   Thanks to Sean Devlin and Watson Ladd of Cryptography Services, NCC
   Group for discovering this issue.
   ([CVE-2014-3512])

   *Steve Henson*

 * A flaw in the OpenSSL SSL/TLS server code causes the server to negotiate
   TLS 1.0 instead of higher protocol versions when the ClientHello message
   is badly fragmented. This allows a man-in-the-middle attacker to force a
   downgrade to TLS 1.0 even if both the server and the client support a
   higher protocol version, by modifying the client's TLS records.

   Thanks to David Benjamin and Adam Langley (Google) for discovering and
   researching this issue.
   ([CVE-2014-3511])

   *David Benjamin*

 * OpenSSL DTLS clients enabling anonymous (EC)DH ciphersuites are subject
   to a denial of service attack. A malicious server can crash the client
   with a null pointer dereference (read) by specifying an anonymous (EC)DH
   ciphersuite and sending carefully crafted handshake messages.

   Thanks to Felix Gröbert (Google) for discovering and researching this
   issue.
   ([CVE-2014-3510])

   *Emilia Käsper*

 * By sending carefully crafted DTLS packets an attacker could cause openssl
   to leak memory. This can be exploited through a Denial of Service attack.
   Thanks to Adam Langley for discovering and researching this issue.
   ([CVE-2014-3507])

   *Adam Langley*

 * An attacker can force openssl to consume large amounts of memory whilst
   processing DTLS handshake messages. This can be exploited through a
   Denial of Service attack.
   Thanks to Adam Langley for discovering and researching this issue.
   ([CVE-2014-3506])

   *Adam Langley*

 * An attacker can force an error condition which causes openssl to crash
   whilst processing DTLS packets due to memory being freed twice. This
   can be exploited through a Denial of Service attack.
   Thanks to Adam Langley and Wan-Teh Chang for discovering and researching
   this issue.
   ([CVE-2014-3505])

   *Adam Langley*

 * If a multithreaded client connects to a malicious server using a resumed
   session and the server sends an ec point format extension it could write
   up to 255 bytes to freed memory.

   Thanks to Gabor Tyukasz (LogMeIn Inc) for discovering and researching this
   issue.
   ([CVE-2014-3509])

   *Gabor Tyukasz*

 * A malicious server can crash an OpenSSL client with a null pointer
   dereference (read) by specifying an SRP ciphersuite even though it was not
   properly negotiated with the client. This can be exploited through a
   Denial of Service attack.

   Thanks to Joonas Kuorilehto and Riku Hietamäki (Codenomicon) for
   discovering and researching this issue.
   ([CVE-2014-5139])

   *Steve Henson*

 * A flaw in OBJ_obj2txt may cause pretty printing functions such as
   X509_name_oneline, X509_name_print_ex et al. to leak some information
   from the stack. Applications may be affected if they echo pretty printing
   output to the attacker.

   Thanks to Ivan Fratric (Google) for discovering this issue.
   ([CVE-2014-3508])

   *Emilia Käsper, and Steve Henson*

 * Fix ec_GFp_simple_points_make_affine (thus, EC_POINTs_mul etc.)
   for corner cases. (Certain input points at infinity could lead to
   bogus results, with non-infinity inputs mapped to infinity too.)

   *Bodo Moeller*

### Changes between 1.0.1g and 1.0.1h [5 Jun 2014]

 * Fix for SSL/TLS MITM flaw. An attacker using a carefully crafted
   handshake can force the use of weak keying material in OpenSSL
   SSL/TLS clients and servers.

   Thanks to KIKUCHI Masashi (Lepidum Co. Ltd.) for discovering and
   researching this issue. ([CVE-2014-0224])

   *KIKUCHI Masashi, Steve Henson*

 * Fix DTLS recursion flaw. By sending an invalid DTLS handshake to an
   OpenSSL DTLS client the code can be made to recurse eventually crashing
   in a DoS attack.

   Thanks to Imre Rad (Search-Lab Ltd.) for discovering this issue.
   ([CVE-2014-0221])

   *Imre Rad, Steve Henson*

 * Fix DTLS invalid fragment vulnerability. A buffer overrun attack can
   be triggered by sending invalid DTLS fragments to an OpenSSL DTLS
   client or server. This is potentially exploitable to run arbitrary
   code on a vulnerable client or server.

   Thanks to Jüri Aedla for reporting this issue. ([CVE-2014-0195])

   *Jüri Aedla, Steve Henson*

 * Fix bug in TLS code where clients enable anonymous ECDH ciphersuites
   are subject to a denial of service attack.

   Thanks to Felix Gröbert and Ivan Fratric at Google for discovering
   this issue. ([CVE-2014-3470])

   *Felix Gröbert, Ivan Fratric, Steve Henson*

 * Harmonize version and its documentation. -f flag is used to display
   compilation flags.

   *mancha <mancha1@zoho.com>*

 * Fix eckey_priv_encode so it immediately returns an error upon a failure
   in i2d_ECPrivateKey.

   *mancha <mancha1@zoho.com>*

 * Fix some double frees. These are not thought to be exploitable.

   *mancha <mancha1@zoho.com>*

### Changes between 1.0.1f and 1.0.1g [7 Apr 2014]

 * A missing bounds check in the handling of the TLS heartbeat extension
   can be used to reveal up to 64k of memory to a connected client or
   server.

   Thanks for Neel Mehta of Google Security for discovering this bug and to
   Adam Langley <agl@chromium.org> and Bodo Moeller <bmoeller@acm.org> for
   preparing the fix ([CVE-2014-0160])

   *Adam Langley, Bodo Moeller*

 * Fix for the attack described in the paper "Recovering OpenSSL
   ECDSA Nonces Using the FLUSH+RELOAD Cache Side-channel Attack"
   by Yuval Yarom and Naomi Benger. Details can be obtained from:
   <http://eprint.iacr.org/2014/140>

   Thanks to Yuval Yarom and Naomi Benger for discovering this
   flaw and to Yuval Yarom for supplying a fix ([CVE-2014-0076])

   *Yuval Yarom and Naomi Benger*

 * TLS pad extension: draft-agl-tls-padding-03

   Workaround for the "TLS hang bug" (see FAQ and PR#2771): if the
   TLS client Hello record length value would otherwise be > 255 and
   less that 512 pad with a dummy extension containing zeroes so it
   is at least 512 bytes long.

   *Adam Langley, Steve Henson*

### Changes between 1.0.1e and 1.0.1f [6 Jan 2014]

 * Fix for TLS record tampering bug. A carefully crafted invalid
   handshake could crash OpenSSL with a NULL pointer exception.
   Thanks to Anton Johansson for reporting this issues.
   ([CVE-2013-4353])

 * Keep original DTLS digest and encryption contexts in retransmission
   structures so we can use the previous session parameters if they need
   to be resent. ([CVE-2013-6450])

   *Steve Henson*

 * Add option SSL_OP_SAFARI_ECDHE_ECDSA_BUG (part of SSL_OP_ALL) which
   avoids preferring ECDHE-ECDSA ciphers when the client appears to be
   Safari on OS X.  Safari on OS X 10.8..10.8.3 advertises support for
   several ECDHE-ECDSA ciphers, but fails to negotiate them.  The bug
   is fixed in OS X 10.8.4, but Apple have ruled out both hot fixing
   10.8..10.8.3 and forcing users to upgrade to 10.8.4 or newer.

   *Rob Stradling, Adam Langley*

### Changes between 1.0.1d and 1.0.1e [11 Feb 2013]

 * Correct fix for CVE-2013-0169. The original didn't work on AES-NI
   supporting platforms or when small records were transferred.

   *Andy Polyakov, Steve Henson*

### Changes between 1.0.1c and 1.0.1d [5 Feb 2013]

 * Make the decoding of SSLv3, TLS and DTLS CBC records constant time.

   This addresses the flaw in CBC record processing discovered by
   Nadhem Alfardan and Kenny Paterson. Details of this attack can be found
   at: <http://www.isg.rhul.ac.uk/tls/>

   Thanks go to Nadhem Alfardan and Kenny Paterson of the Information
   Security Group at Royal Holloway, University of London
   (www.isg.rhul.ac.uk) for discovering this flaw and Adam Langley and
   Emilia Käsper for the initial patch.
   ([CVE-2013-0169])

   *Emilia Käsper, Adam Langley, Ben Laurie, Andy Polyakov, Steve Henson*

 * Fix flaw in AESNI handling of TLS 1.2 and 1.1 records for CBC mode
   ciphersuites which can be exploited in a denial of service attack.
   Thanks go to and to Adam Langley <agl@chromium.org> for discovering
   and detecting this bug and to Wolfgang Ettlinger
   <wolfgang.ettlinger@gmail.com> for independently discovering this issue.
   ([CVE-2012-2686])

   *Adam Langley*

 * Return an error when checking OCSP signatures when key is NULL.
   This fixes a DoS attack. ([CVE-2013-0166])

   *Steve Henson*

 * Make openssl verify return errors.

   *Chris Palmer <palmer@google.com> and Ben Laurie*

 * Call OCSP Stapling callback after ciphersuite has been chosen, so
   the right response is stapled. Also change SSL_get_certificate()
   so it returns the certificate actually sent.
   See <http://rt.openssl.org/Ticket/Display.html?id=2836>.

   *Rob Stradling <rob.stradling@comodo.com>*

 * Fix possible deadlock when decoding public keys.

   *Steve Henson*

 * Don't use TLS 1.0 record version number in initial client hello
   if renegotiating.

   *Steve Henson*

### Changes between 1.0.1b and 1.0.1c [10 May 2012]

 * Sanity check record length before skipping explicit IV in TLS
   1.2, 1.1 and DTLS to fix DoS attack.

   Thanks to Codenomicon for discovering this issue using Fuzz-o-Matic
   fuzzing as a service testing platform.
   ([CVE-2012-2333])

   *Steve Henson*

 * Initialise tkeylen properly when encrypting CMS messages.
   Thanks to Solar Designer of Openwall for reporting this issue.

   *Steve Henson*

 * In FIPS mode don't try to use composite ciphers as they are not
   approved.

   *Steve Henson*

### Changes between 1.0.1a and 1.0.1b [26 Apr 2012]

 * OpenSSL 1.0.0 sets SSL_OP_ALL to 0x80000FFFL and OpenSSL 1.0.1 and
   1.0.1a set SSL_OP_NO_TLSv1_1 to 0x00000400L which would unfortunately
   mean any application compiled against OpenSSL 1.0.0 headers setting
   SSL_OP_ALL would also set SSL_OP_NO_TLSv1_1, unintentionally disabling
   TLS 1.1 also. Fix this by changing the value of SSL_OP_NO_TLSv1_1 to
   0x10000000L Any application which was previously compiled against
   OpenSSL 1.0.1 or 1.0.1a headers and which cares about SSL_OP_NO_TLSv1_1
   will need to be recompiled as a result. Letting be results in
   inability to disable specifically TLS 1.1 and in client context,
   in unlike event, limit maximum offered version to TLS 1.0 [see below].

   *Steve Henson*

 * In order to ensure interoperability SSL_OP_NO_protocolX does not
   disable just protocol X, but all protocols above X *if* there are
   protocols *below* X still enabled. In more practical terms it means
   that if application wants to disable TLS1.0 in favor of TLS1.1 and
   above, it's not sufficient to pass `SSL_OP_NO_TLSv1`, one has to pass
   `SSL_OP_NO_TLSv1|SSL_OP_NO_SSLv3|SSL_OP_NO_SSLv2`. This applies to
   client side.

   *Andy Polyakov*

### Changes between 1.0.1 and 1.0.1a [19 Apr 2012]

 * Check for potentially exploitable overflows in asn1_d2i_read_bio
   BUF_mem_grow and BUF_mem_grow_clean. Refuse attempts to shrink buffer
   in CRYPTO_realloc_clean.

   Thanks to Tavis Ormandy, Google Security Team, for discovering this
   issue and to Adam Langley <agl@chromium.org> for fixing it.
   ([CVE-2012-2110])

   *Adam Langley (Google), Tavis Ormandy, Google Security Team*

 * Don't allow TLS 1.2 SHA-256 ciphersuites in TLS 1.0, 1.1 connections.

   *Adam Langley*

 * Workarounds for some broken servers that "hang" if a client hello
   record length exceeds 255 bytes.

   1. Do not use record version number > TLS 1.0 in initial client
      hello: some (but not all) hanging servers will now work.
   2. If we set OPENSSL_MAX_TLS1_2_CIPHER_LENGTH this will truncate
      the number of ciphers sent in the client hello. This should be
      set to an even number, such as 50, for example by passing:
      -DOPENSSL_MAX_TLS1_2_CIPHER_LENGTH=50 to config or Configure.
      Most broken servers should now work.
   3. If all else fails setting OPENSSL_NO_TLS1_2_CLIENT will disable
      TLS 1.2 client support entirely.

   *Steve Henson*

 * Fix SEGV in Vector Permutation AES module observed in OpenSSH.

   *Andy Polyakov*

### Changes between 1.0.0h and 1.0.1  [14 Mar 2012]

 * Add compatibility with old MDC2 signatures which use an ASN1 OCTET
   STRING form instead of a DigestInfo.

   *Steve Henson*

 * The format used for MDC2 RSA signatures is inconsistent between EVP
   and the RSA_sign/RSA_verify functions. This was made more apparent when
   OpenSSL used RSA_sign/RSA_verify for some RSA signatures in particular
   those which went through EVP_PKEY_METHOD in 1.0.0 and later. Detect
   the correct format in RSA_verify so both forms transparently work.

   *Steve Henson*

 * Some servers which support TLS 1.0 can choke if we initially indicate
   support for TLS 1.2 and later renegotiate using TLS 1.0 in the RSA
   encrypted premaster secret. As a workaround use the maximum permitted
   client version in client hello, this should keep such servers happy
   and still work with previous versions of OpenSSL.

   *Steve Henson*

 * Add support for TLS/DTLS heartbeats.

   *Robin Seggelmann <seggelmann@fh-muenster.de>*

 * Add support for SCTP.

   *Robin Seggelmann <seggelmann@fh-muenster.de>*

 * Improved PRNG seeding for VOS.

   *Paul Green <Paul.Green@stratus.com>*

 * Extensive assembler packs updates, most notably:

   - x86[_64]:     AES-NI, PCLMULQDQ, RDRAND support;
   - x86[_64]:     SSSE3 support (SHA1, vector-permutation AES);
   - x86_64:       bit-sliced AES implementation;
   - ARM:          NEON support, contemporary platforms optimizations;
   - s390x:        z196 support;
   - `*`:            GHASH and GF(2^m) multiplication implementations;

   *Andy Polyakov*

 * Make TLS-SRP code conformant with RFC 5054 API cleanup
   (removal of unnecessary code)

   *Peter Sylvester <peter.sylvester@edelweb.fr>*

 * Add TLS key material exporter from RFC 5705.

   *Eric Rescorla*

 * Add DTLS-SRTP negotiation from RFC 5764.

   *Eric Rescorla*

 * Add Next Protocol Negotiation,
   <http://tools.ietf.org/html/draft-agl-tls-nextprotoneg-00>. Can be
   disabled with a no-npn flag to config or Configure. Code donated
   by Google.

   *Adam Langley <agl@google.com> and Ben Laurie*

 * Add optional 64-bit optimized implementations of elliptic curves NIST-P224,
   NIST-P256, NIST-P521, with constant-time single point multiplication on
   typical inputs. Compiler support for the nonstandard type `__uint128_t` is
   required to use this (present in gcc 4.4 and later, for 64-bit builds).
   Code made available under Apache License version 2.0.

   Specify "enable-ec_nistp_64_gcc_128" on the Configure (or config) command
   line to include this in your build of OpenSSL, and run "make depend" (or
   "make update"). This enables the following EC_METHODs:

           EC_GFp_nistp224_method()
           EC_GFp_nistp256_method()
           EC_GFp_nistp521_method()

   EC_GROUP_new_by_curve_name() will automatically use these (while
   EC_GROUP_new_curve_GFp() currently prefers the more flexible
   implementations).

   *Emilia Käsper, Adam Langley, Bodo Moeller (Google)*

 * Use type ossl_ssize_t instead of ssize_t which isn't available on
   all platforms. Move ssize_t definition from e_os.h to the public
   header file e_os2.h as it now appears in public header file cms.h

   *Steve Henson*

 * New -sigopt option to the ca, req and x509 utilities. Additional
   signature parameters can be passed using this option and in
   particular PSS.

   *Steve Henson*

 * Add RSA PSS signing function. This will generate and set the
   appropriate AlgorithmIdentifiers for PSS based on those in the
   corresponding EVP_MD_CTX structure. No application support yet.

   *Steve Henson*

 * Support for companion algorithm specific ASN1 signing routines.
   New function ASN1_item_sign_ctx() signs a pre-initialised
   EVP_MD_CTX structure and sets AlgorithmIdentifiers based on
   the appropriate parameters.

   *Steve Henson*

 * Add new algorithm specific ASN1 verification initialisation function
   to EVP_PKEY_ASN1_METHOD: this is not in EVP_PKEY_METHOD since the ASN1
   handling will be the same no matter what EVP_PKEY_METHOD is used.
   Add a PSS handler to support verification of PSS signatures: checked
   against a number of sample certificates.

   *Steve Henson*

 * Add signature printing for PSS. Add PSS OIDs.

   *Steve Henson, Martin Kaiser <lists@kaiser.cx>*

 * Add algorithm specific signature printing. An individual ASN1 method
   can now print out signatures instead of the standard hex dump.

   More complex signatures (e.g. PSS) can print out more meaningful
   information. Include DSA version that prints out the signature
   parameters r, s.

   *Steve Henson*

 * Password based recipient info support for CMS library: implementing
   RFC3211.

   *Steve Henson*

 * Split password based encryption into PBES2 and PBKDF2 functions. This
   neatly separates the code into cipher and PBE sections and is required
   for some algorithms that split PBES2 into separate pieces (such as
   password based CMS).

   *Steve Henson*

 * Session-handling fixes:
   - Fix handling of connections that are resuming with a session ID,
     but also support Session Tickets.
   - Fix a bug that suppressed issuing of a new ticket if the client
     presented a ticket with an expired session.
   - Try to set the ticket lifetime hint to something reasonable.
   - Make tickets shorter by excluding irrelevant information.
   - On the client side, don't ignore renewed tickets.

   *Adam Langley, Bodo Moeller (Google)*

 * Fix PSK session representation.

   *Bodo Moeller*

 * Add RC4-MD5 and AESNI-SHA1 "stitched" implementations.

   This work was sponsored by Intel.

   *Andy Polyakov*

 * Add GCM support to TLS library. Some custom code is needed to split
   the IV between the fixed (from PRF) and explicit (from TLS record)
   portions. This adds all GCM ciphersuites supported by RFC5288 and
   RFC5289. Generalise some `AES*` cipherstrings to include GCM and
   add a special AESGCM string for GCM only.

   *Steve Henson*

 * Expand range of ctrls for AES GCM. Permit setting invocation
   field on decrypt and retrieval of invocation field only on encrypt.

   *Steve Henson*

 * Add HMAC ECC ciphersuites from RFC5289. Include SHA384 PRF support.
   As required by RFC5289 these ciphersuites cannot be used if for
   versions of TLS earlier than 1.2.

   *Steve Henson*

 * For FIPS capable OpenSSL interpret a NULL default public key method
   as unset and return the appropriate default but do *not* set the default.
   This means we can return the appropriate method in applications that
   switch between FIPS and non-FIPS modes.

   *Steve Henson*

 * Redirect HMAC and CMAC operations to FIPS module in FIPS mode. If an
   ENGINE is used then we cannot handle that in the FIPS module so we
   keep original code iff non-FIPS operations are allowed.

   *Steve Henson*

 * Add -attime option to openssl utilities.

   *Peter Eckersley <pde@eff.org>, Ben Laurie and Steve Henson*

 * Redirect DSA and DH operations to FIPS module in FIPS mode.

   *Steve Henson*

 * Redirect ECDSA and ECDH operations to FIPS module in FIPS mode. Also use
   FIPS EC methods unconditionally for now.

   *Steve Henson*

 * New build option no-ec2m to disable characteristic 2 code.

   *Steve Henson*

 * Backport libcrypto audit of return value checking from 1.1.0-dev; not
   all cases can be covered as some introduce binary incompatibilities.

   *Steve Henson*

 * Redirect RSA operations to FIPS module including keygen,
   encrypt, decrypt, sign and verify. Block use of non FIPS RSA methods.

   *Steve Henson*

 * Add similar low-level API blocking to ciphers.

   *Steve Henson*

 * low-level digest APIs are not approved in FIPS mode: any attempt
   to use these will cause a fatal error. Applications that *really* want
   to use them can use the `private_*` version instead.

   *Steve Henson*

 * Redirect cipher operations to FIPS module for FIPS builds.

   *Steve Henson*

 * Redirect digest operations to FIPS module for FIPS builds.

   *Steve Henson*

 * Update build system to add "fips" flag which will link in fipscanister.o
   for static and shared library builds embedding a signature if needed.

   *Steve Henson*

 * Output TLS supported curves in preference order instead of numerical
   order. This is currently hardcoded for the highest order curves first.
   This should be configurable so applications can judge speed vs strength.

   *Steve Henson*

 * Add TLS v1.2 server support for client authentication.

   *Steve Henson*

 * Add support for FIPS mode in ssl library: disable SSLv3, non-FIPS ciphers
   and enable MD5.

   *Steve Henson*

 * Functions FIPS_mode_set() and FIPS_mode() which call the underlying
   FIPS modules versions.

   *Steve Henson*

 * Add TLS v1.2 client side support for client authentication. Keep cache
   of handshake records longer as we don't know the hash algorithm to use
   until after the certificate request message is received.

   *Steve Henson*

 * Initial TLS v1.2 client support. Add a default signature algorithms
   extension including all the algorithms we support. Parse new signature
   format in client key exchange. Relax some ECC signing restrictions for
   TLS v1.2 as indicated in RFC5246.

   *Steve Henson*

 * Add server support for TLS v1.2 signature algorithms extension. Switch
   to new signature format when needed using client digest preference.
   All server ciphersuites should now work correctly in TLS v1.2. No client
   support yet and no support for client certificates.

   *Steve Henson*

 * Initial TLS v1.2 support. Add new SHA256 digest to ssl code, switch
   to SHA256 for PRF when using TLS v1.2 and later. Add new SHA256 based
   ciphersuites. At present only RSA key exchange ciphersuites work with
   TLS v1.2. Add new option for TLS v1.2 replacing the old and obsolete
   SSL_OP_PKCS1_CHECK flags with SSL_OP_NO_TLSv1_2. New TLSv1.2 methods
   and version checking.

   *Steve Henson*

 * New option OPENSSL_NO_SSL_INTERN. If an application can be compiled
   with this defined it will not be affected by any changes to ssl internal
   structures. Add several utility functions to allow openssl application
   to work with OPENSSL_NO_SSL_INTERN defined.

   *Steve Henson*

 * A long standing patch to add support for SRP from EdelWeb (Peter
   Sylvester and Christophe Renou) was integrated.
   *Christophe Renou <christophe.renou@edelweb.fr>, Peter Sylvester
   <peter.sylvester@edelweb.fr>, Tom Wu <tjw@cs.stanford.edu>, and
   Ben Laurie*

 * Add functions to copy EVP_PKEY_METHOD and retrieve flags and id.

   *Steve Henson*

 * Permit abbreviated handshakes when renegotiating using the function
   SSL_renegotiate_abbreviated().

   *Robin Seggelmann <seggelmann@fh-muenster.de>*

 * Add call to ENGINE_register_all_complete() to
   ENGINE_load_builtin_engines(), so some implementations get used
   automatically instead of needing explicit application support.

   *Steve Henson*

 * Add support for TLS key exporter as described in RFC5705.

   *Robin Seggelmann <seggelmann@fh-muenster.de>, Steve Henson*

 * Initial TLSv1.1 support. Since TLSv1.1 is very similar to TLS v1.0 only
   a few changes are required:

     Add SSL_OP_NO_TLSv1_1 flag.
     Add TLSv1_1 methods.
     Update version checking logic to handle version 1.1.
     Add explicit IV handling (ported from DTLS code).
     Add command line options to s_client/s_server.

   *Steve Henson*

OpenSSL 1.0.0
-------------

### Changes between 1.0.0s and 1.0.0t [3 Dec 2015]

 * X509_ATTRIBUTE memory leak

   When presented with a malformed X509_ATTRIBUTE structure OpenSSL will leak
   memory. This structure is used by the PKCS#7 and CMS routines so any
   application which reads PKCS#7 or CMS data from untrusted sources is
   affected. SSL/TLS is not affected.

   This issue was reported to OpenSSL by Adam Langley (Google/BoringSSL) using
   libFuzzer.
   ([CVE-2015-3195])

   *Stephen Henson*

 * Race condition handling PSK identify hint

   If PSK identity hints are received by a multi-threaded client then
   the values are wrongly updated in the parent SSL_CTX structure. This can
   result in a race condition potentially leading to a double free of the
   identify hint data.
   ([CVE-2015-3196])

   *Stephen Henson*

### Changes between 1.0.0r and 1.0.0s [11 Jun 2015]

 * Malformed ECParameters causes infinite loop

   When processing an ECParameters structure OpenSSL enters an infinite loop
   if the curve specified is over a specially malformed binary polynomial
   field.

   This can be used to perform denial of service against any
   system which processes public keys, certificate requests or
   certificates.  This includes TLS clients and TLS servers with
   client authentication enabled.

   This issue was reported to OpenSSL by Joseph Barr-Pixton.
   ([CVE-2015-1788])

   *Andy Polyakov*

 * Exploitable out-of-bounds read in X509_cmp_time

   X509_cmp_time does not properly check the length of the ASN1_TIME
   string and can read a few bytes out of bounds. In addition,
   X509_cmp_time accepts an arbitrary number of fractional seconds in the
   time string.

   An attacker can use this to craft malformed certificates and CRLs of
   various sizes and potentially cause a segmentation fault, resulting in
   a DoS on applications that verify certificates or CRLs. TLS clients
   that verify CRLs are affected. TLS clients and servers with client
   authentication enabled may be affected if they use custom verification
   callbacks.

   This issue was reported to OpenSSL by Robert Swiecki (Google), and
   independently by Hanno Böck.
   ([CVE-2015-1789])

   *Emilia Käsper*

 * PKCS7 crash with missing EnvelopedContent

   The PKCS#7 parsing code does not handle missing inner EncryptedContent
   correctly. An attacker can craft malformed ASN.1-encoded PKCS#7 blobs
   with missing content and trigger a NULL pointer dereference on parsing.

   Applications that decrypt PKCS#7 data or otherwise parse PKCS#7
   structures from untrusted sources are affected. OpenSSL clients and
   servers are not affected.

   This issue was reported to OpenSSL by Michal Zalewski (Google).
   ([CVE-2015-1790])

   *Emilia Käsper*

 * CMS verify infinite loop with unknown hash function

   When verifying a signedData message the CMS code can enter an infinite loop
   if presented with an unknown hash function OID. This can be used to perform
   denial of service against any system which verifies signedData messages using
   the CMS code.
   This issue was reported to OpenSSL by Johannes Bauer.
   ([CVE-2015-1792])

   *Stephen Henson*

 * Race condition handling NewSessionTicket

   If a NewSessionTicket is received by a multi-threaded client when attempting to
   reuse a previous ticket then a race condition can occur potentially leading to
   a double free of the ticket data.
   ([CVE-2015-1791])

   *Matt Caswell*

### Changes between 1.0.0q and 1.0.0r [19 Mar 2015]

 * Segmentation fault in ASN1_TYPE_cmp fix

   The function ASN1_TYPE_cmp will crash with an invalid read if an attempt is
   made to compare ASN.1 boolean types. Since ASN1_TYPE_cmp is used to check
   certificate signature algorithm consistency this can be used to crash any
   certificate verification operation and exploited in a DoS attack. Any
   application which performs certificate verification is vulnerable including
   OpenSSL clients and servers which enable client authentication.
   ([CVE-2015-0286])

   *Stephen Henson*

 * ASN.1 structure reuse memory corruption fix

   Reusing a structure in ASN.1 parsing may allow an attacker to cause
   memory corruption via an invalid write. Such reuse is and has been
   strongly discouraged and is believed to be rare.

   Applications that parse structures containing CHOICE or ANY DEFINED BY
   components may be affected. Certificate parsing (d2i_X509 and related
   functions) are however not affected. OpenSSL clients and servers are
   not affected.
   ([CVE-2015-0287])

   *Stephen Henson*

 * PKCS7 NULL pointer dereferences fix

   The PKCS#7 parsing code does not handle missing outer ContentInfo
   correctly. An attacker can craft malformed ASN.1-encoded PKCS#7 blobs with
   missing content and trigger a NULL pointer dereference on parsing.

   Applications that verify PKCS#7 signatures, decrypt PKCS#7 data or
   otherwise parse PKCS#7 structures from untrusted sources are
   affected. OpenSSL clients and servers are not affected.

   This issue was reported to OpenSSL by Michal Zalewski (Google).
   ([CVE-2015-0289])

   *Emilia Käsper*

 * DoS via reachable assert in SSLv2 servers fix

   A malicious client can trigger an OPENSSL_assert (i.e., an abort) in
   servers that both support SSLv2 and enable export cipher suites by sending
   a specially crafted SSLv2 CLIENT-MASTER-KEY message.

   This issue was discovered by Sean Burford (Google) and Emilia Käsper
   (OpenSSL development team).
   ([CVE-2015-0293])

   *Emilia Käsper*

 * Use After Free following d2i_ECPrivatekey error fix

   A malformed EC private key file consumed via the d2i_ECPrivateKey function
   could cause a use after free condition. This, in turn, could cause a double
   free in several private key parsing functions (such as d2i_PrivateKey
   or EVP_PKCS82PKEY) and could lead to a DoS attack or memory corruption
   for applications that receive EC private keys from untrusted
   sources. This scenario is considered rare.

   This issue was discovered by the BoringSSL project and fixed in their
   commit 517073cd4b.
   ([CVE-2015-0209])

   *Matt Caswell*

 * X509_to_X509_REQ NULL pointer deref fix

   The function X509_to_X509_REQ will crash with a NULL pointer dereference if
   the certificate key is invalid. This function is rarely used in practice.

   This issue was discovered by Brian Carpenter.
   ([CVE-2015-0288])

   *Stephen Henson*

 * Removed the export ciphers from the DEFAULT ciphers

   *Kurt Roeckx*

### Changes between 1.0.0p and 1.0.0q [15 Jan 2015]

 * Build fixes for the Windows and OpenVMS platforms

   *Matt Caswell and Richard Levitte*

### Changes between 1.0.0o and 1.0.0p [8 Jan 2015]

 * Fix DTLS segmentation fault in dtls1_get_record. A carefully crafted DTLS
   message can cause a segmentation fault in OpenSSL due to a NULL pointer
   dereference. This could lead to a Denial Of Service attack. Thanks to
   Markus Stenberg of Cisco Systems, Inc. for reporting this issue.
   ([CVE-2014-3571])

   *Steve Henson*

 * Fix DTLS memory leak in dtls1_buffer_record. A memory leak can occur in the
   dtls1_buffer_record function under certain conditions. In particular this
   could occur if an attacker sent repeated DTLS records with the same
   sequence number but for the next epoch. The memory leak could be exploited
   by an attacker in a Denial of Service attack through memory exhaustion.
   Thanks to Chris Mueller for reporting this issue.
   ([CVE-2015-0206])

   *Matt Caswell*

 * Fix issue where no-ssl3 configuration sets method to NULL. When openssl is
   built with the no-ssl3 option and a SSL v3 ClientHello is received the ssl
   method would be set to NULL which could later result in a NULL pointer
   dereference. Thanks to Frank Schmirler for reporting this issue.
   ([CVE-2014-3569])

   *Kurt Roeckx*

 * Abort handshake if server key exchange message is omitted for ephemeral
   ECDH ciphersuites.

   Thanks to Karthikeyan Bhargavan of the PROSECCO team at INRIA for
   reporting this issue.
   ([CVE-2014-3572])

   *Steve Henson*

 * Remove non-export ephemeral RSA code on client and server. This code
   violated the TLS standard by allowing the use of temporary RSA keys in
   non-export ciphersuites and could be used by a server to effectively
   downgrade the RSA key length used to a value smaller than the server
   certificate. Thanks for Karthikeyan Bhargavan of the PROSECCO team at
   INRIA or reporting this issue.
   ([CVE-2015-0204])

   *Steve Henson*

 * Fixed issue where DH client certificates are accepted without verification.
   An OpenSSL server will accept a DH certificate for client authentication
   without the certificate verify message. This effectively allows a client to
   authenticate without the use of a private key. This only affects servers
   which trust a client certificate authority which issues certificates
   containing DH keys: these are extremely rare and hardly ever encountered.
   Thanks for Karthikeyan Bhargavan of the PROSECCO team at INRIA or reporting
   this issue.
   ([CVE-2015-0205])

   *Steve Henson*

 * Correct Bignum squaring. Bignum squaring (BN_sqr) may produce incorrect
   results on some platforms, including x86_64. This bug occurs at random
   with a very low probability, and is not known to be exploitable in any
   way, though its exact impact is difficult to determine. Thanks to Pieter
   Wuille (Blockstream) who reported this issue and also suggested an initial
   fix. Further analysis was conducted by the OpenSSL development team and
   Adam Langley of Google. The final fix was developed by Andy Polyakov of
   the OpenSSL core team.
   ([CVE-2014-3570])

   *Andy Polyakov*

 * Fix various certificate fingerprint issues.

   By using non-DER or invalid encodings outside the signed portion of a
   certificate the fingerprint can be changed without breaking the signature.
   Although no details of the signed portion of the certificate can be changed
   this can cause problems with some applications: e.g. those using the
   certificate fingerprint for blacklists.

   1. Reject signatures with non zero unused bits.

   If the BIT STRING containing the signature has non zero unused bits reject
   the signature. All current signature algorithms require zero unused bits.

   2. Check certificate algorithm consistency.

   Check the AlgorithmIdentifier inside TBS matches the one in the
   certificate signature. NB: this will result in signature failure
   errors for some broken certificates.

   Thanks to Konrad Kraszewski from Google for reporting this issue.

   3. Check DSA/ECDSA signatures use DER.

   Reencode DSA/ECDSA signatures and compare with the original received
   signature. Return an error if there is a mismatch.

   This will reject various cases including garbage after signature
   (thanks to Antti Karjalainen and Tuomo Untinen from the Codenomicon CROSS
   program for discovering this case) and use of BER or invalid ASN.1 INTEGERs
   (negative or with leading zeroes).

   Further analysis was conducted and fixes were developed by Stephen Henson
   of the OpenSSL core team.

   ([CVE-2014-8275])

   *Steve Henson*

### Changes between 1.0.0n and 1.0.0o [15 Oct 2014]

 * Session Ticket Memory Leak.

   When an OpenSSL SSL/TLS/DTLS server receives a session ticket the
   integrity of that ticket is first verified. In the event of a session
   ticket integrity check failing, OpenSSL will fail to free memory
   causing a memory leak. By sending a large number of invalid session
   tickets an attacker could exploit this issue in a Denial Of Service
   attack.
   ([CVE-2014-3567])

   *Steve Henson*

 * Build option no-ssl3 is incomplete.

   When OpenSSL is configured with "no-ssl3" as a build option, servers
   could accept and complete an SSL 3.0 handshake, and clients could be
   configured to send them.
   ([CVE-2014-3568])

   *Akamai and the OpenSSL team*

 * Add support for TLS_FALLBACK_SCSV.
   Client applications doing fallback retries should call
   SSL_set_mode(s, SSL_MODE_SEND_FALLBACK_SCSV).
   ([CVE-2014-3566])

   *Adam Langley, Bodo Moeller*

 * Add additional DigestInfo checks.

   Reencode DigestInto in DER and check against the original when
   verifying RSA signature: this will reject any improperly encoded
   DigestInfo structures.

   Note: this is a precautionary measure and no attacks are currently known.

   *Steve Henson*

### Changes between 1.0.0m and 1.0.0n [6 Aug 2014]

 * OpenSSL DTLS clients enabling anonymous (EC)DH ciphersuites are subject
   to a denial of service attack. A malicious server can crash the client
   with a null pointer dereference (read) by specifying an anonymous (EC)DH
   ciphersuite and sending carefully crafted handshake messages.

   Thanks to Felix Gröbert (Google) for discovering and researching this
   issue.
   ([CVE-2014-3510])

   *Emilia Käsper*

 * By sending carefully crafted DTLS packets an attacker could cause openssl
   to leak memory. This can be exploited through a Denial of Service attack.
   Thanks to Adam Langley for discovering and researching this issue.
   ([CVE-2014-3507])

   *Adam Langley*

 * An attacker can force openssl to consume large amounts of memory whilst
   processing DTLS handshake messages. This can be exploited through a
   Denial of Service attack.
   Thanks to Adam Langley for discovering and researching this issue.
   ([CVE-2014-3506])

   *Adam Langley*

 * An attacker can force an error condition which causes openssl to crash
   whilst processing DTLS packets due to memory being freed twice. This
   can be exploited through a Denial of Service attack.
   Thanks to Adam Langley and Wan-Teh Chang for discovering and researching
   this issue.
   ([CVE-2014-3505])

   *Adam Langley*

 * If a multithreaded client connects to a malicious server using a resumed
   session and the server sends an ec point format extension it could write
   up to 255 bytes to freed memory.

   Thanks to Gabor Tyukasz (LogMeIn Inc) for discovering and researching this
   issue.
   ([CVE-2014-3509])

   *Gabor Tyukasz*

 * A flaw in OBJ_obj2txt may cause pretty printing functions such as
   X509_name_oneline, X509_name_print_ex et al. to leak some information
   from the stack. Applications may be affected if they echo pretty printing
   output to the attacker.

   Thanks to Ivan Fratric (Google) for discovering this issue.
   ([CVE-2014-3508])

   *Emilia Käsper, and Steve Henson*

 * Fix ec_GFp_simple_points_make_affine (thus, EC_POINTs_mul etc.)
   for corner cases. (Certain input points at infinity could lead to
   bogus results, with non-infinity inputs mapped to infinity too.)

   *Bodo Moeller*

### Changes between 1.0.0l and 1.0.0m [5 Jun 2014]

 * Fix for SSL/TLS MITM flaw. An attacker using a carefully crafted
   handshake can force the use of weak keying material in OpenSSL
   SSL/TLS clients and servers.

   Thanks to KIKUCHI Masashi (Lepidum Co. Ltd.) for discovering and
   researching this issue. ([CVE-2014-0224])

   *KIKUCHI Masashi, Steve Henson*

 * Fix DTLS recursion flaw. By sending an invalid DTLS handshake to an
   OpenSSL DTLS client the code can be made to recurse eventually crashing
   in a DoS attack.

   Thanks to Imre Rad (Search-Lab Ltd.) for discovering this issue.
   ([CVE-2014-0221])

   *Imre Rad, Steve Henson*

 * Fix DTLS invalid fragment vulnerability. A buffer overrun attack can
   be triggered by sending invalid DTLS fragments to an OpenSSL DTLS
   client or server. This is potentially exploitable to run arbitrary
   code on a vulnerable client or server.

   Thanks to Jüri Aedla for reporting this issue. ([CVE-2014-0195])

   *Jüri Aedla, Steve Henson*

 * Fix bug in TLS code where clients enable anonymous ECDH ciphersuites
   are subject to a denial of service attack.

   Thanks to Felix Gröbert and Ivan Fratric at Google for discovering
   this issue. ([CVE-2014-3470])

   *Felix Gröbert, Ivan Fratric, Steve Henson*

 * Harmonize version and its documentation. -f flag is used to display
   compilation flags.

   *mancha <mancha1@zoho.com>*

 * Fix eckey_priv_encode so it immediately returns an error upon a failure
   in i2d_ECPrivateKey.

   *mancha <mancha1@zoho.com>*

 * Fix some double frees. These are not thought to be exploitable.

   *mancha <mancha1@zoho.com>*

 * Fix for the attack described in the paper "Recovering OpenSSL
   ECDSA Nonces Using the FLUSH+RELOAD Cache Side-channel Attack"
   by Yuval Yarom and Naomi Benger. Details can be obtained from:
   <http://eprint.iacr.org/2014/140>

   Thanks to Yuval Yarom and Naomi Benger for discovering this
   flaw and to Yuval Yarom for supplying a fix ([CVE-2014-0076])

   *Yuval Yarom and Naomi Benger*

### Changes between 1.0.0k and 1.0.0l [6 Jan 2014]

 * Keep original DTLS digest and encryption contexts in retransmission
   structures so we can use the previous session parameters if they need
   to be resent. ([CVE-2013-6450])

   *Steve Henson*

 * Add option SSL_OP_SAFARI_ECDHE_ECDSA_BUG (part of SSL_OP_ALL) which
   avoids preferring ECDHE-ECDSA ciphers when the client appears to be
   Safari on OS X.  Safari on OS X 10.8..10.8.3 advertises support for
   several ECDHE-ECDSA ciphers, but fails to negotiate them.  The bug
   is fixed in OS X 10.8.4, but Apple have ruled out both hot fixing
   10.8..10.8.3 and forcing users to upgrade to 10.8.4 or newer.

   *Rob Stradling, Adam Langley*

### Changes between 1.0.0j and 1.0.0k [5 Feb 2013]

 * Make the decoding of SSLv3, TLS and DTLS CBC records constant time.

   This addresses the flaw in CBC record processing discovered by
   Nadhem Alfardan and Kenny Paterson. Details of this attack can be found
   at: <http://www.isg.rhul.ac.uk/tls/>

   Thanks go to Nadhem Alfardan and Kenny Paterson of the Information
   Security Group at Royal Holloway, University of London
   (www.isg.rhul.ac.uk) for discovering this flaw and Adam Langley and
   Emilia Käsper for the initial patch.
   ([CVE-2013-0169])

   *Emilia Käsper, Adam Langley, Ben Laurie, Andy Polyakov, Steve Henson*

 * Return an error when checking OCSP signatures when key is NULL.
   This fixes a DoS attack. ([CVE-2013-0166])

   *Steve Henson*

 * Call OCSP Stapling callback after ciphersuite has been chosen, so
   the right response is stapled. Also change SSL_get_certificate()
   so it returns the certificate actually sent.
   See <http://rt.openssl.org/Ticket/Display.html?id=2836>.
   (This is a backport)

   *Rob Stradling <rob.stradling@comodo.com>*

 * Fix possible deadlock when decoding public keys.

   *Steve Henson*

### Changes between 1.0.0i and 1.0.0j [10 May 2012]

[NB: OpenSSL 1.0.0i and later 1.0.0 patch levels were released after
OpenSSL 1.0.1.]

 * Sanity check record length before skipping explicit IV in DTLS
   to fix DoS attack.

   Thanks to Codenomicon for discovering this issue using Fuzz-o-Matic
   fuzzing as a service testing platform.
   ([CVE-2012-2333])

   *Steve Henson*

 * Initialise tkeylen properly when encrypting CMS messages.
   Thanks to Solar Designer of Openwall for reporting this issue.

   *Steve Henson*

### Changes between 1.0.0h and 1.0.0i [19 Apr 2012]

 * Check for potentially exploitable overflows in asn1_d2i_read_bio
   BUF_mem_grow and BUF_mem_grow_clean. Refuse attempts to shrink buffer
   in CRYPTO_realloc_clean.

   Thanks to Tavis Ormandy, Google Security Team, for discovering this
   issue and to Adam Langley <agl@chromium.org> for fixing it.
   ([CVE-2012-2110])

   *Adam Langley (Google), Tavis Ormandy, Google Security Team*

### Changes between 1.0.0g and 1.0.0h [12 Mar 2012]

 * Fix MMA (Bleichenbacher's attack on PKCS #1 v1.5 RSA padding) weakness
   in CMS and PKCS7 code. When RSA decryption fails use a random key for
   content decryption and always return the same error. Note: this attack
   needs on average 2^20 messages so it only affects automated senders. The
   old behaviour can be re-enabled in the CMS code by setting the
   CMS_DEBUG_DECRYPT flag: this is useful for debugging and testing where
   an MMA defence is not necessary.
   Thanks to Ivan Nestlerode <inestlerode@us.ibm.com> for discovering
   this issue. ([CVE-2012-0884])

   *Steve Henson*

 * Fix CVE-2011-4619: make sure we really are receiving a
   client hello before rejecting multiple SGC restarts. Thanks to
   Ivan Nestlerode <inestlerode@us.ibm.com> for discovering this bug.

   *Steve Henson*

### Changes between 1.0.0f and 1.0.0g [18 Jan 2012]

 * Fix for DTLS DoS issue introduced by fix for CVE-2011-4109.
   Thanks to Antonio Martin, Enterprise Secure Access Research and
   Development, Cisco Systems, Inc. for discovering this bug and
   preparing a fix. ([CVE-2012-0050])

   *Antonio Martin*

### Changes between 1.0.0e and 1.0.0f [4 Jan 2012]

 * Nadhem Alfardan and Kenny Paterson have discovered an extension
   of the Vaudenay padding oracle attack on CBC mode encryption
   which enables an efficient plaintext recovery attack against
   the OpenSSL implementation of DTLS. Their attack exploits timing
   differences arising during decryption processing. A research
   paper describing this attack can be found at:
   <http://www.isg.rhul.ac.uk/~kp/dtls.pdf>
   Thanks go to Nadhem Alfardan and Kenny Paterson of the Information
   Security Group at Royal Holloway, University of London
   (www.isg.rhul.ac.uk) for discovering this flaw and to Robin Seggelmann
   <seggelmann@fh-muenster.de> and Michael Tuexen <tuexen@fh-muenster.de>
   for preparing the fix. ([CVE-2011-4108])

   *Robin Seggelmann, Michael Tuexen*

 * Clear bytes used for block padding of SSL 3.0 records.
   ([CVE-2011-4576])

   *Adam Langley (Google)*

 * Only allow one SGC handshake restart for SSL/TLS. Thanks to George
   Kadianakis <desnacked@gmail.com> for discovering this issue and
   Adam Langley for preparing the fix. ([CVE-2011-4619])

   *Adam Langley (Google)*

 * Check parameters are not NULL in GOST ENGINE. ([CVE-2012-0027])

   *Andrey Kulikov <amdeich@gmail.com>*

 * Prevent malformed RFC3779 data triggering an assertion failure.
   Thanks to Andrew Chi, BBN Technologies, for discovering the flaw
   and Rob Austein <sra@hactrn.net> for fixing it. ([CVE-2011-4577])

   *Rob Austein <sra@hactrn.net>*

 * Improved PRNG seeding for VOS.

   *Paul Green <Paul.Green@stratus.com>*

 * Fix ssl_ciph.c set-up race.

   *Adam Langley (Google)*

 * Fix spurious failures in ecdsatest.c.

   *Emilia Käsper (Google)*

 * Fix the BIO_f_buffer() implementation (which was mixing different
   interpretations of the `..._len` fields).

   *Adam Langley (Google)*

 * Fix handling of BN_BLINDING: now BN_BLINDING_invert_ex (rather than
   BN_BLINDING_invert_ex) calls BN_BLINDING_update, ensuring that concurrent
   threads won't reuse the same blinding coefficients.

   This also avoids the need to obtain the CRYPTO_LOCK_RSA_BLINDING
   lock to call BN_BLINDING_invert_ex, and avoids one use of
   BN_BLINDING_update for each BN_BLINDING structure (previously,
   the last update always remained unused).

   *Emilia Käsper (Google)*

 * In ssl3_clear, preserve s3->init_extra along with s3->rbuf.

   *Bob Buckholz (Google)*

### Changes between 1.0.0d and 1.0.0e [6 Sep 2011]

 * Fix bug where CRLs with nextUpdate in the past are sometimes accepted
   by initialising X509_STORE_CTX properly. ([CVE-2011-3207])

   *Kaspar Brand <ossl@velox.ch>*

 * Fix SSL memory handling for (EC)DH ciphersuites, in particular
   for multi-threaded use of ECDH. ([CVE-2011-3210])

   *Adam Langley (Google)*

 * Fix x509_name_ex_d2i memory leak on bad inputs.

   *Bodo Moeller*

 * Remove hard coded ecdsaWithSHA1 signature tests in ssl code and check
   signature public key algorithm by using OID xref utilities instead.
   Before this you could only use some ECC ciphersuites with SHA1 only.

   *Steve Henson*

 * Add protection against ECDSA timing attacks as mentioned in the paper
   by Billy Bob Brumley and Nicola Tuveri, see:
   <http://eprint.iacr.org/2011/232.pdf>

   *Billy Bob Brumley and Nicola Tuveri*

### Changes between 1.0.0c and 1.0.0d [8 Feb 2011]

 * Fix parsing of OCSP stapling ClientHello extension. CVE-2011-0014

   *Neel Mehta, Adam Langley, Bodo Moeller (Google)*

 * Fix bug in string printing code: if *any* escaping is enabled we must
   escape the escape character (backslash) or the resulting string is
   ambiguous.

   *Steve Henson*

### Changes between 1.0.0b and 1.0.0c  [2 Dec 2010]

 * Disable code workaround for ancient and obsolete Netscape browsers
   and servers: an attacker can use it in a ciphersuite downgrade attack.
   Thanks to Martin Rex for discovering this bug. CVE-2010-4180

   *Steve Henson*

 * Fixed J-PAKE implementation error, originally discovered by
   Sebastien Martini, further info and confirmation from Stefan
   Arentz and Feng Hao. Note that this fix is a security fix. CVE-2010-4252

   *Ben Laurie*

### Changes between 1.0.0a and 1.0.0b  [16 Nov 2010]

 * Fix extension code to avoid race conditions which can result in a buffer
   overrun vulnerability: resumed sessions must not be modified as they can
   be shared by multiple threads. CVE-2010-3864

   *Steve Henson*

 * Fix WIN32 build system to correctly link an ENGINE directory into
   a DLL.

   *Steve Henson*

### Changes between 1.0.0 and 1.0.0a  [01 Jun 2010]

 * Check return value of int_rsa_verify in pkey_rsa_verifyrecover
   ([CVE-2010-1633])

   *Steve Henson, Peter-Michael Hager <hager@dortmund.net>*

### Changes between 0.9.8n and 1.0.0  [29 Mar 2010]

 * Add "missing" function EVP_CIPHER_CTX_copy(). This copies a cipher
   context. The operation can be customised via the ctrl mechanism in
   case ENGINEs want to include additional functionality.

   *Steve Henson*

 * Tolerate yet another broken PKCS#8 key format: private key value negative.

   *Steve Henson*

 * Add new -subject_hash_old and -issuer_hash_old options to x509 utility to
   output hashes compatible with older versions of OpenSSL.

   *Willy Weisz <weisz@vcpc.univie.ac.at>*

 * Fix compression algorithm handling: if resuming a session use the
   compression algorithm of the resumed session instead of determining
   it from client hello again. Don't allow server to change algorithm.

   *Steve Henson*

 * Add load_crls() function to commands tidying load_certs() too. Add option
   to verify utility to allow additional CRLs to be included.

   *Steve Henson*

 * Update OCSP request code to permit adding custom headers to the request:
   some responders need this.

   *Steve Henson*

 * The function EVP_PKEY_sign() returns <=0 on error: check return code
   correctly.

   *Julia Lawall <julia@diku.dk>*

 * Update verify callback code in `apps/s_cb.c` and `apps/verify.c`, it
   needlessly dereferenced structures, used obsolete functions and
   didn't handle all updated verify codes correctly.

   *Steve Henson*

 * Disable MD2 in the default configuration.

   *Steve Henson*

 * In BIO_pop() and BIO_push() use the ctrl argument (which was NULL) to
   indicate the initial BIO being pushed or popped. This makes it possible
   to determine whether the BIO is the one explicitly called or as a result
   of the ctrl being passed down the chain. Fix BIO_pop() and SSL BIOs so
   it handles reference counts correctly and doesn't zero out the I/O bio
   when it is not being explicitly popped. WARNING: applications which
   included workarounds for the old buggy behaviour will need to be modified
   or they could free up already freed BIOs.

   *Steve Henson*

 * Extend the uni2asc/asc2uni => OPENSSL_uni2asc/OPENSSL_asc2uni
   renaming to all platforms (within the 0.9.8 branch, this was
   done conditionally on Netware platforms to avoid a name clash).

   *Guenter <lists@gknw.net>*

 * Add ECDHE and PSK support to DTLS.

   *Michael Tuexen <tuexen@fh-muenster.de>*

 * Add CHECKED_STACK_OF macro to safestack.h, otherwise safestack can't
   be used on C++.

   *Steve Henson*

 * Add "missing" function EVP_MD_flags() (without this the only way to
   retrieve a digest flags is by accessing the structure directly. Update
   `EVP_MD_do_all*()` and `EVP_CIPHER_do_all*()` to include the name a digest
   or cipher is registered as in the "from" argument. Print out all
   registered digests in the dgst usage message instead of manually
   attempting to work them out.

   *Steve Henson*

 * If no SSLv2 ciphers are used don't use an SSLv2 compatible client hello:
   this allows the use of compression and extensions. Change default cipher
   string to remove SSLv2 ciphersuites. This effectively avoids ancient SSLv2
   by default unless an application cipher string requests it.

   *Steve Henson*

 * Alter match criteria in PKCS12_parse(). It used to try to use local
   key ids to find matching certificates and keys but some PKCS#12 files
   don't follow the (somewhat unwritten) rules and this strategy fails.
   Now just gather all certificates together and the first private key
   then look for the first certificate that matches the key.

   *Steve Henson*

 * Support use of registered digest and cipher names for dgst and cipher
   commands instead of having to add each one as a special case. So now
   you can do:

           openssl sha256 foo

   as well as:

           openssl dgst -sha256 foo

   and this works for ENGINE based algorithms too.

   *Steve Henson*

 * Update Gost ENGINE to support parameter files.

   *Victor B. Wagner <vitus@cryptocom.ru>*

 * Support GeneralizedTime in ca utility.

   *Oliver Martin <oliver@volatilevoid.net>, Steve Henson*

 * Enhance the hash format used for certificate directory links. The new
   form uses the canonical encoding (meaning equivalent names will work
   even if they aren't identical) and uses SHA1 instead of MD5. This form
   is incompatible with the older format and as a result c_rehash should
   be used to rebuild symbolic links.

   *Steve Henson*

 * Make PKCS#8 the default write format for private keys, replacing the
   traditional format. This form is standardised, more secure and doesn't
   include an implicit MD5 dependency.

   *Steve Henson*

 * Add a $gcc_devteam_warn option to Configure. The idea is that any code
   committed to OpenSSL should pass this lot as a minimum.

   *Steve Henson*

 * Add session ticket override functionality for use by EAP-FAST.

   *Jouni Malinen <j@w1.fi>*

 * Modify HMAC functions to return a value. Since these can be implemented
   in an ENGINE errors can occur.

   *Steve Henson*

 * Type-checked OBJ_bsearch_ex.

   *Ben Laurie*

 * Type-checked OBJ_bsearch. Also some constification necessitated
   by type-checking.  Still to come: TXT_DB, bsearch(?),
   OBJ_bsearch_ex, qsort, CRYPTO_EX_DATA, ASN1_VALUE, ASN1_STRING,
   CONF_VALUE.

   *Ben Laurie*

 * New function OPENSSL_gmtime_adj() to add a specific number of days and
   seconds to a tm structure directly, instead of going through OS
   specific date routines. This avoids any issues with OS routines such
   as the year 2038 bug. New `*_adj()` functions for ASN1 time structures
   and X509_time_adj_ex() to cover the extended range. The existing
   X509_time_adj() is still usable and will no longer have any date issues.

   *Steve Henson*

 * Delta CRL support. New use deltas option which will attempt to locate
   and search any appropriate delta CRLs available.

   This work was sponsored by Google.

   *Steve Henson*

 * Support for CRLs partitioned by reason code. Reorganise CRL processing
   code and add additional score elements. Validate alternate CRL paths
   as part of the CRL checking and indicate a new error "CRL path validation
   error" in this case. Applications wanting additional details can use
   the verify callback and check the new "parent" field. If this is not
   NULL CRL path validation is taking place. Existing applications won't
   see this because it requires extended CRL support which is off by
   default.

   This work was sponsored by Google.

   *Steve Henson*

 * Support for freshest CRL extension.

   This work was sponsored by Google.

   *Steve Henson*

 * Initial indirect CRL support. Currently only supported in the CRLs
   passed directly and not via lookup. Process certificate issuer
   CRL entry extension and lookup CRL entries by bother issuer name
   and serial number. Check and process CRL issuer entry in IDP extension.

   This work was sponsored by Google.

   *Steve Henson*

 * Add support for distinct certificate and CRL paths. The CRL issuer
   certificate is validated separately in this case. Only enabled if
   an extended CRL support flag is set: this flag will enable additional
   CRL functionality in future.

   This work was sponsored by Google.

   *Steve Henson*

 * Add support for policy mappings extension.

   This work was sponsored by Google.

   *Steve Henson*

 * Fixes to pathlength constraint, self issued certificate handling,
   policy processing to align with RFC3280 and PKITS tests.

   This work was sponsored by Google.

   *Steve Henson*

 * Support for name constraints certificate extension. DN, email, DNS
   and URI types are currently supported.

   This work was sponsored by Google.

   *Steve Henson*

 * To cater for systems that provide a pointer-based thread ID rather
   than numeric, deprecate the current numeric thread ID mechanism and
   replace it with a structure and associated callback type. This
   mechanism allows a numeric "hash" to be extracted from a thread ID in
   either case, and on platforms where pointers are larger than 'long',
   mixing is done to help ensure the numeric 'hash' is usable even if it
   can't be guaranteed unique. The default mechanism is to use "&errno"
   as a pointer-based thread ID to distinguish between threads.

   Applications that want to provide their own thread IDs should now use
   CRYPTO_THREADID_set_callback() to register a callback that will call
   either CRYPTO_THREADID_set_numeric() or CRYPTO_THREADID_set_pointer().

   Note that ERR_remove_state() is now deprecated, because it is tied
   to the assumption that thread IDs are numeric.  ERR_remove_state(0)
   to free the current thread's error state should be replaced by
   ERR_remove_thread_state(NULL).

   (This new approach replaces the functions CRYPTO_set_idptr_callback(),
   CRYPTO_get_idptr_callback(), and CRYPTO_thread_idptr() that existed in
   OpenSSL 0.9.9-dev between June 2006 and August 2008. Also, if an
   application was previously providing a numeric thread callback that
   was inappropriate for distinguishing threads, then uniqueness might
   have been obtained with &errno that happened immediately in the
   intermediate development versions of OpenSSL; this is no longer the
   case, the numeric thread callback will now override the automatic use
   of &errno.)

   *Geoff Thorpe, with help from Bodo Moeller*

 * Initial support for different CRL issuing certificates. This covers a
   simple case where the self issued certificates in the chain exist and
   the real CRL issuer is higher in the existing chain.

   This work was sponsored by Google.

   *Steve Henson*

 * Removed effectively defunct crypto/store from the build.

   *Ben Laurie*

 * Revamp of STACK to provide stronger type-checking. Still to come:
   TXT_DB, bsearch(?), OBJ_bsearch, qsort, CRYPTO_EX_DATA, ASN1_VALUE,
   ASN1_STRING, CONF_VALUE.

   *Ben Laurie*

 * Add a new SSL_MODE_RELEASE_BUFFERS mode flag to release unused buffer
   RAM on SSL connections.  This option can save about 34k per idle SSL.

   *Nick Mathewson*

 * Revamp of LHASH to provide stronger type-checking. Still to come:
   STACK, TXT_DB, bsearch, qsort.

   *Ben Laurie*

 * Initial support for Cryptographic Message Syntax (aka CMS) based
   on RFC3850, RFC3851 and RFC3852. New cms directory and cms utility,
   support for data, signedData, compressedData, digestedData and
   encryptedData, envelopedData types included. Scripts to check against
   RFC4134 examples draft and interop and consistency checks of many
   content types and variants.

   *Steve Henson*

 * Add options to enc utility to support use of zlib compression BIO.

   *Steve Henson*

 * Extend mk1mf to support importing of options and assembly language
   files from Configure script, currently only included in VC-WIN32.
   The assembly language rules can now optionally generate the source
   files from the associated perl scripts.

   *Steve Henson*

 * Implement remaining functionality needed to support GOST ciphersuites.
   Interop testing has been performed using CryptoPro implementations.

   *Victor B. Wagner <vitus@cryptocom.ru>*

 * s390x assembler pack.

   *Andy Polyakov*

 * ARMv4 assembler pack. ARMv4 refers to v4 and later ISA, not CPU
   "family."

   *Andy Polyakov*

 * Implement Opaque PRF Input TLS extension as specified in
   draft-rescorla-tls-opaque-prf-input-00.txt.  Since this is not an
   official specification yet and no extension type assignment by
   IANA exists, this extension (for now) will have to be explicitly
   enabled when building OpenSSL by providing the extension number
   to use.  For example, specify an option

           -DTLSEXT_TYPE_opaque_prf_input=0x9527

   to the "config" or "Configure" script to enable the extension,
   assuming extension number 0x9527 (which is a completely arbitrary
   and unofficial assignment based on the MD5 hash of the Internet
   Draft).  Note that by doing so, you potentially lose
   interoperability with other TLS implementations since these might
   be using the same extension number for other purposes.

   SSL_set_tlsext_opaque_prf_input(ssl, src, len) is used to set the
   opaque PRF input value to use in the handshake.  This will create
   an internal copy of the length-'len' string at 'src', and will
   return non-zero for success.

   To get more control and flexibility, provide a callback function
   by using

           SSL_CTX_set_tlsext_opaque_prf_input_callback(ctx, cb)
           SSL_CTX_set_tlsext_opaque_prf_input_callback_arg(ctx, arg)

   where

           int (*cb)(SSL *, void *peerinput, size_t len, void *arg);
           void *arg;

   Callback function 'cb' will be called in handshakes, and is
   expected to use SSL_set_tlsext_opaque_prf_input() as appropriate.
   Argument 'arg' is for application purposes (the value as given to
   SSL_CTX_set_tlsext_opaque_prf_input_callback_arg() will directly
   be provided to the callback function).  The callback function
   has to return non-zero to report success: usually 1 to use opaque
   PRF input just if possible, or 2 to enforce use of the opaque PRF
   input.  In the latter case, the library will abort the handshake
   if opaque PRF input is not successfully negotiated.

   Arguments 'peerinput' and 'len' given to the callback function
   will always be NULL and 0 in the case of a client.  A server will
   see the client's opaque PRF input through these variables if
   available (NULL and 0 otherwise).  Note that if the server
   provides an opaque PRF input, the length must be the same as the
   length of the client's opaque PRF input.

   Note that the callback function will only be called when creating
   a new session (session resumption can resume whatever was
   previously negotiated), and will not be called in SSL 2.0
   handshakes; thus, SSL_CTX_set_options(ctx, SSL_OP_NO_SSLv2) or
   SSL_set_options(ssl, SSL_OP_NO_SSLv2) is especially recommended
   for applications that need to enforce opaque PRF input.

   *Bodo Moeller*

 * Update ssl code to support digests other than SHA1+MD5 for handshake
   MAC.

   *Victor B. Wagner <vitus@cryptocom.ru>*

 * Add RFC4507 support to OpenSSL. This includes the corrections in
   RFC4507bis. The encrypted ticket format is an encrypted encoded
   SSL_SESSION structure, that way new session features are automatically
   supported.

   If a client application caches session in an SSL_SESSION structure
   support is transparent because tickets are now stored in the encoded
   SSL_SESSION.

   The SSL_CTX structure automatically generates keys for ticket
   protection in servers so again support should be possible
   with no application modification.

   If a client or server wishes to disable RFC4507 support then the option
   SSL_OP_NO_TICKET can be set.

   Add a TLS extension debugging callback to allow the contents of any client
   or server extensions to be examined.

   This work was sponsored by Google.

   *Steve Henson*

 * Final changes to avoid use of pointer pointer casts in OpenSSL.
   OpenSSL should now compile cleanly on gcc 4.2

   *Peter Hartley <pdh@utter.chaos.org.uk>, Steve Henson*

 * Update SSL library to use new EVP_PKEY MAC API. Include generic MAC
   support including streaming MAC support: this is required for GOST
   ciphersuite support.

   *Victor B. Wagner <vitus@cryptocom.ru>, Steve Henson*

 * Add option -stream to use PKCS#7 streaming in smime utility. New
   function i2d_PKCS7_bio_stream() and PEM_write_PKCS7_bio_stream()
   to output in BER and PEM format.

   *Steve Henson*

 * Experimental support for use of HMAC via EVP_PKEY interface. This
   allows HMAC to be handled via the `EVP_DigestSign*()` interface. The
   EVP_PKEY "key" in this case is the HMAC key, potentially allowing
   ENGINE support for HMAC keys which are unextractable. New -mac and
   -macopt options to dgst utility.

   *Steve Henson*

 * New option -sigopt to dgst utility. Update dgst to use
   `EVP_Digest{Sign,Verify}*`. These two changes make it possible to use
   alternative signing parameters such as X9.31 or PSS in the dgst
   utility.

   *Steve Henson*

 * Change ssl_cipher_apply_rule(), the internal function that does
   the work each time a ciphersuite string requests enabling
   ("foo+bar"), moving ("+foo+bar"), disabling ("-foo+bar", or
   removing ("!foo+bar") a class of ciphersuites: Now it maintains
   the order of disabled ciphersuites such that those ciphersuites
   that most recently went from enabled to disabled not only stay
   in order with respect to each other, but also have higher priority
   than other disabled ciphersuites the next time ciphersuites are
   enabled again.

   This means that you can now say, e.g., "PSK:-PSK:HIGH" to enable
   the same ciphersuites as with "HIGH" alone, but in a specific
   order where the PSK ciphersuites come first (since they are the
   most recently disabled ciphersuites when "HIGH" is parsed).

   Also, change ssl_create_cipher_list() (using this new
   functionality) such that between otherwise identical
   ciphersuites, ephemeral ECDH is preferred over ephemeral DH in
   the default order.

   *Bodo Moeller*

 * Change ssl_create_cipher_list() so that it automatically
   arranges the ciphersuites in reasonable order before starting
   to process the rule string.  Thus, the definition for "DEFAULT"
   (SSL_DEFAULT_CIPHER_LIST) now is just "ALL:!aNULL:!eNULL", but
   remains equivalent to `"AES:ALL:!aNULL:!eNULL:+aECDH:+kRSA:+RC4:@STRENGTH"`.
   This makes it much easier to arrive at a reasonable default order
   in applications for which anonymous ciphers are OK (meaning
   that you can't actually use DEFAULT).

   *Bodo Moeller; suggested by Victor Duchovni*

 * Split the SSL/TLS algorithm mask (as used for ciphersuite string
   processing) into multiple integers instead of setting
   "SSL_MKEY_MASK" bits, "SSL_AUTH_MASK" bits, "SSL_ENC_MASK",
   "SSL_MAC_MASK", and "SSL_SSL_MASK" bits all in a single integer.
   (These masks as well as the individual bit definitions are hidden
   away into the non-exported interface ssl/ssl_locl.h, so this
   change to the definition of the SSL_CIPHER structure shouldn't
   affect applications.)  This give us more bits for each of these
   categories, so there is no longer a need to coagulate AES128 and
   AES256 into a single algorithm bit, and to coagulate Camellia128
   and Camellia256 into a single algorithm bit, which has led to all
   kinds of kludges.

   Thus, among other things, the kludge introduced in 0.9.7m and
   0.9.8e for masking out AES256 independently of AES128 or masking
   out Camellia256 independently of AES256 is not needed here in 0.9.9.

   With the change, we also introduce new ciphersuite aliases that
   so far were missing: "AES128", "AES256", "CAMELLIA128", and
   "CAMELLIA256".

   *Bodo Moeller*

 * Add support for dsa-with-SHA224 and dsa-with-SHA256.
   Use the leftmost N bytes of the signature input if the input is
   larger than the prime q (with N being the size in bytes of q).

   *Nils Larsch*

 * Very *very* experimental PKCS#7 streaming encoder support. Nothing uses
   it yet and it is largely untested.

   *Steve Henson*

 * Add support for the ecdsa-with-SHA224/256/384/512 signature types.

   *Nils Larsch*

 * Initial incomplete changes to avoid need for function casts in OpenSSL
   some compilers (gcc 4.2 and later) reject their use. Safestack is
   reimplemented.  Update ASN1 to avoid use of legacy functions.

   *Steve Henson*

 * Win32/64 targets are linked with Winsock2.

   *Andy Polyakov*

 * Add an X509_CRL_METHOD structure to allow CRL processing to be redirected
   to external functions. This can be used to increase CRL handling
   efficiency especially when CRLs are very large by (for example) storing
   the CRL revoked certificates in a database.

   *Steve Henson*

 * Overhaul of by_dir code. Add support for dynamic loading of CRLs so
   new CRLs added to a directory can be used. New command line option
   -verify_return_error to s_client and s_server. This causes real errors
   to be returned by the verify callback instead of carrying on no matter
   what. This reflects the way a "real world" verify callback would behave.

   *Steve Henson*

 * GOST engine, supporting several GOST algorithms and public key formats.
   Kindly donated by Cryptocom.

   *Cryptocom*

 * Partial support for Issuing Distribution Point CRL extension. CRLs
   partitioned by DP are handled but no indirect CRL or reason partitioning
   (yet). Complete overhaul of CRL handling: now the most suitable CRL is
   selected via a scoring technique which handles IDP and AKID in CRLs.

   *Steve Henson*

 * New X509_STORE_CTX callbacks lookup_crls() and lookup_certs() which
   will ultimately be used for all verify operations: this will remove the
   X509_STORE dependency on certificate verification and allow alternative
   lookup methods.  X509_STORE based implementations of these two callbacks.

   *Steve Henson*

 * Allow multiple CRLs to exist in an X509_STORE with matching issuer names.
   Modify get_crl() to find a valid (unexpired) CRL if possible.

   *Steve Henson*

 * New function X509_CRL_match() to check if two CRLs are identical. Normally
   this would be called X509_CRL_cmp() but that name is already used by
   a function that just compares CRL issuer names. Cache several CRL
   extensions in X509_CRL structure and cache CRLDP in X509.

   *Steve Henson*

 * Store a "canonical" representation of X509_NAME structure (ASN1 Name)
   this maps equivalent X509_NAME structures into a consistent structure.
   Name comparison can then be performed rapidly using memcmp().

   *Steve Henson*

 * Non-blocking OCSP request processing. Add -timeout option to ocsp
   utility.

   *Steve Henson*

 * Allow digests to supply their own micalg string for S/MIME type using
   the ctrl EVP_MD_CTRL_MICALG.

   *Steve Henson*

 * During PKCS7 signing pass the PKCS7 SignerInfo structure to the
   EVP_PKEY_METHOD before and after signing via the EVP_PKEY_CTRL_PKCS7_SIGN
   ctrl. It can then customise the structure before and/or after signing
   if necessary.

   *Steve Henson*

 * New function OBJ_add_sigid() to allow application defined signature OIDs
   to be added to OpenSSLs internal tables. New function OBJ_sigid_free()
   to free up any added signature OIDs.

   *Steve Henson*

 * New functions EVP_CIPHER_do_all(), EVP_CIPHER_do_all_sorted(),
   EVP_MD_do_all() and EVP_MD_do_all_sorted() to enumerate internal
   digest and cipher tables. New options added to openssl utility:
   list-message-digest-algorithms and list-cipher-algorithms.

   *Steve Henson*

 * Change the array representation of binary polynomials: the list
   of degrees of non-zero coefficients is now terminated with -1.
   Previously it was terminated with 0, which was also part of the
   value; thus, the array representation was not applicable to
   polynomials where t^0 has coefficient zero.  This change makes
   the array representation useful in a more general context.

   *Douglas Stebila*

 * Various modifications and fixes to SSL/TLS cipher string
   handling.  For ECC, the code now distinguishes between fixed ECDH
   with RSA certificates on the one hand and with ECDSA certificates
   on the other hand, since these are separate ciphersuites.  The
   unused code for Fortezza ciphersuites has been removed.

   For consistency with EDH, ephemeral ECDH is now called "EECDH"
   (not "ECDHE").  For consistency with the code for DH
   certificates, use of ECDH certificates is now considered ECDH
   authentication, not RSA or ECDSA authentication (the latter is
   merely the CA's signing algorithm and not actively used in the
   protocol).

   The temporary ciphersuite alias "ECCdraft" is no longer
   available, and ECC ciphersuites are no longer excluded from "ALL"
   and "DEFAULT".  The following aliases now exist for RFC 4492
   ciphersuites, most of these by analogy with the DH case:

           kECDHr   - ECDH cert, signed with RSA
           kECDHe   - ECDH cert, signed with ECDSA
           kECDH    - ECDH cert (signed with either RSA or ECDSA)
           kEECDH   - ephemeral ECDH
           ECDH     - ECDH cert or ephemeral ECDH

           aECDH    - ECDH cert
           aECDSA   - ECDSA cert
           ECDSA    - ECDSA cert

           AECDH    - anonymous ECDH
           EECDH    - non-anonymous ephemeral ECDH (equivalent to "kEECDH:-AECDH")

   *Bodo Moeller*

 * Add additional S/MIME capabilities for AES and GOST ciphers if supported.
   Use correct micalg parameters depending on digest(s) in signed message.

   *Steve Henson*

 * Add engine support for EVP_PKEY_ASN1_METHOD. Add functions to process
   an ENGINE asn1 method. Support ENGINE lookups in the ASN1 code.

   *Steve Henson*

 * Initial engine support for EVP_PKEY_METHOD. New functions to permit
   an engine to register a method. Add ENGINE lookups for methods and
   functional reference processing.

   *Steve Henson*

 * New functions `EVP_Digest{Sign,Verify)*`. These are enhanced versions of
   `EVP_{Sign,Verify}*` which allow an application to customise the signature
   process.

   *Steve Henson*

 * New -resign option to smime utility. This adds one or more signers
   to an existing PKCS#7 signedData structure. Also -md option to use an
   alternative message digest algorithm for signing.

   *Steve Henson*

 * Tidy up PKCS#7 routines and add new functions to make it easier to
   create PKCS7 structures containing multiple signers. Update smime
   application to support multiple signers.

   *Steve Henson*

 * New -macalg option to pkcs12 utility to allow setting of an alternative
   digest MAC.

   *Steve Henson*

 * Initial support for PKCS#5 v2.0 PRFs other than default SHA1 HMAC.
   Reorganize PBE internals to lookup from a static table using NIDs,
   add support for HMAC PBE OID translation. Add a EVP_CIPHER ctrl:
   EVP_CTRL_PBE_PRF_NID this allows a cipher to specify an alternative
   PRF which will be automatically used with PBES2.

   *Steve Henson*

 * Replace the algorithm specific calls to generate keys in "req" with the
   new API.

   *Steve Henson*

 * Update PKCS#7 enveloped data routines to use new API. This is now
   supported by any public key method supporting the encrypt operation. A
   ctrl is added to allow the public key algorithm to examine or modify
   the PKCS#7 RecipientInfo structure if it needs to: for RSA this is
   a no op.

   *Steve Henson*

 * Add a ctrl to asn1 method to allow a public key algorithm to express
   a default digest type to use. In most cases this will be SHA1 but some
   algorithms (such as GOST) need to specify an alternative digest. The
   return value indicates how strong the preference is 1 means optional and
   2 is mandatory (that is it is the only supported type). Modify
   ASN1_item_sign() to accept a NULL digest argument to indicate it should
   use the default md. Update openssl utilities to use the default digest
   type for signing if it is not explicitly indicated.

   *Steve Henson*

 * Use OID cross reference table in ASN1_sign() and ASN1_verify(). New
   EVP_MD flag EVP_MD_FLAG_PKEY_METHOD_SIGNATURE. This uses the relevant
   signing method from the key type. This effectively removes the link
   between digests and public key types.

   *Steve Henson*

 * Add an OID cross reference table and utility functions. Its purpose is to
   translate between signature OIDs such as SHA1WithrsaEncryption and SHA1,
   rsaEncryption. This will allow some of the algorithm specific hackery
   needed to use the correct OID to be removed.

   *Steve Henson*

 * Remove algorithm specific dependencies when setting PKCS7_SIGNER_INFO
   structures for PKCS7_sign(). They are now set up by the relevant public
   key ASN1 method.

   *Steve Henson*

 * Add provisional EC pkey method with support for ECDSA and ECDH.

   *Steve Henson*

 * Add support for key derivation (agreement) in the API, DH method and
   pkeyutl.

   *Steve Henson*

 * Add DSA pkey method and DH pkey methods, extend DH ASN1 method to support
   public and private key formats. As a side effect these add additional
   command line functionality not previously available: DSA signatures can be
   generated and verified using pkeyutl and DH key support and generation in
   pkey, genpkey.

   *Steve Henson*

 * BeOS support.

   *Oliver Tappe <zooey@hirschkaefer.de>*

 * New make target "install_html_docs" installs HTML renditions of the
   manual pages.

   *Oliver Tappe <zooey@hirschkaefer.de>*

 * New utility "genpkey" this is analogous to "genrsa" etc except it can
   generate keys for any algorithm. Extend and update EVP_PKEY_METHOD to
   support key and parameter generation and add initial key generation
   functionality for RSA.

   *Steve Henson*

 * Add functions for main EVP_PKEY_method operations. The undocumented
   functions `EVP_PKEY_{encrypt,decrypt}` have been renamed to
   `EVP_PKEY_{encrypt,decrypt}_old`.

   *Steve Henson*

 * Initial definitions for EVP_PKEY_METHOD. This will be a high level public
   key API, doesn't do much yet.

   *Steve Henson*

 * New function EVP_PKEY_asn1_get0_info() to retrieve information about
   public key algorithms. New option to openssl utility:
   "list-public-key-algorithms" to print out info.

   *Steve Henson*

 * Implement the Supported Elliptic Curves Extension for
   ECC ciphersuites from draft-ietf-tls-ecc-12.txt.

   *Douglas Stebila*

 * Don't free up OIDs in OBJ_cleanup() if they are in use by EVP_MD or
   EVP_CIPHER structures to avoid later problems in EVP_cleanup().

   *Steve Henson*

 * New utilities pkey and pkeyparam. These are similar to algorithm specific
   utilities such as rsa, dsa, dsaparam etc except they process any key
   type.

   *Steve Henson*

 * Transfer public key printing routines to EVP_PKEY_ASN1_METHOD. New
   functions EVP_PKEY_print_public(), EVP_PKEY_print_private(),
   EVP_PKEY_print_param() to print public key data from an EVP_PKEY
   structure.

   *Steve Henson*

 * Initial support for pluggable public key ASN1.
   De-spaghettify the public key ASN1 handling. Move public and private
   key ASN1 handling to a new EVP_PKEY_ASN1_METHOD structure. Relocate
   algorithm specific handling to a single module within the relevant
   algorithm directory. Add functions to allow (near) opaque processing
   of public and private key structures.

   *Steve Henson*

 * Implement the Supported Point Formats Extension for
   ECC ciphersuites from draft-ietf-tls-ecc-12.txt.

   *Douglas Stebila*

 * Add initial support for RFC 4279 PSK TLS ciphersuites. Add members
   for the psk identity [hint] and the psk callback functions to the
   SSL_SESSION, SSL and SSL_CTX structure.

   New ciphersuites:
           PSK-RC4-SHA, PSK-3DES-EDE-CBC-SHA, PSK-AES128-CBC-SHA,
           PSK-AES256-CBC-SHA

   New functions:
           SSL_CTX_use_psk_identity_hint
           SSL_get_psk_identity_hint
           SSL_get_psk_identity
           SSL_use_psk_identity_hint

   *Mika Kousa and Pasi Eronen of Nokia Corporation*

 * Add RFC 3161 compliant time stamp request creation, response generation
   and response verification functionality.

   *Zoltán Glózik <zglozik@opentsa.org>, The OpenTSA Project*

 * Add initial support for TLS extensions, specifically for the server_name
   extension so far.  The SSL_SESSION, SSL_CTX, and SSL data structures now
   have new members for a hostname.  The SSL data structure has an
   additional member `SSL_CTX *initial_ctx` so that new sessions can be
   stored in that context to allow for session resumption, even after the
   SSL has been switched to a new SSL_CTX in reaction to a client's
   server_name extension.

   New functions (subject to change):

           SSL_get_servername()
           SSL_get_servername_type()
           SSL_set_SSL_CTX()

   New CTRL codes and macros (subject to change):

           SSL_CTRL_SET_TLSEXT_SERVERNAME_CB
                               - SSL_CTX_set_tlsext_servername_callback()
           SSL_CTRL_SET_TLSEXT_SERVERNAME_ARG
                                    - SSL_CTX_set_tlsext_servername_arg()
           SSL_CTRL_SET_TLSEXT_HOSTNAME           - SSL_set_tlsext_host_name()

   openssl s_client has a new '-servername ...' option.

   openssl s_server has new options '-servername_host ...', '-cert2 ...',
   '-key2 ...', '-servername_fatal' (subject to change).  This allows
   testing the HostName extension for a specific single hostname ('-cert'
   and '-key' remain fallbacks for handshakes without HostName
   negotiation).  If the unrecognized_name alert has to be sent, this by
   default is a warning; it becomes fatal with the '-servername_fatal'
   option.

   *Peter Sylvester,  Remy Allais, Christophe Renou*

 * Whirlpool hash implementation is added.

   *Andy Polyakov*

 * BIGNUM code on 64-bit SPARCv9 targets is switched from bn(64,64) to
   bn(64,32). Because of instruction set limitations it doesn't have
   any negative impact on performance. This was done mostly in order
   to make it possible to share assembler modules, such as bn_mul_mont
   implementations, between 32- and 64-bit builds without hassle.

   *Andy Polyakov*

 * Move code previously exiled into file crypto/ec/ec2_smpt.c
   to ec2_smpl.c, and no longer require the OPENSSL_EC_BIN_PT_COMP
   macro.

   *Bodo Moeller*

 * New candidate for BIGNUM assembler implementation, bn_mul_mont,
   dedicated Montgomery multiplication procedure, is introduced.
   BN_MONT_CTX is modified to allow bn_mul_mont to reach for higher
   "64-bit" performance on certain 32-bit targets.

   *Andy Polyakov*

 * New option SSL_OP_NO_COMP to disable use of compression selectively
   in SSL structures. New SSL ctrl to set maximum send fragment size.
   Save memory by setting the I/O buffer sizes dynamically instead of
   using the maximum available value.

   *Steve Henson*

 * New option -V for 'openssl ciphers'. This prints the ciphersuite code
   in addition to the text details.

   *Bodo Moeller*

 * Very, very preliminary EXPERIMENTAL support for printing of general
   ASN1 structures. This currently produces rather ugly output and doesn't
   handle several customised structures at all.

   *Steve Henson*

 * Integrated support for PVK file format and some related formats such
   as MS PUBLICKEYBLOB and PRIVATEKEYBLOB. Command line switches to support
   these in the 'rsa' and 'dsa' utilities.

   *Steve Henson*

 * Support for PKCS#1 RSAPublicKey format on rsa utility command line.

   *Steve Henson*

 * Remove the ancient ASN1_METHOD code. This was only ever used in one
   place for the (very old) "NETSCAPE" format certificates which are now
   handled using new ASN1 code equivalents.

   *Steve Henson*

 * Let the TLSv1_method() etc. functions return a 'const' SSL_METHOD
   pointer and make the SSL_METHOD parameter in SSL_CTX_new,
   SSL_CTX_set_ssl_version and SSL_set_ssl_method 'const'.

   *Nils Larsch*

 * Modify CRL distribution points extension code to print out previously
   unsupported fields. Enhance extension setting code to allow setting of
   all fields.

   *Steve Henson*

 * Add print and set support for Issuing Distribution Point CRL extension.

   *Steve Henson*

 * Change 'Configure' script to enable Camellia by default.

   *NTT*

OpenSSL 0.9.x
-------------

### Changes between 0.9.8m and 0.9.8n [24 Mar 2010]

 * When rejecting SSL/TLS records due to an incorrect version number, never
   update s->server with a new major version number.  As of
   - OpenSSL 0.9.8m if 'short' is a 16-bit type,
   - OpenSSL 0.9.8f if 'short' is longer than 16 bits,
   the previous behavior could result in a read attempt at NULL when
   receiving specific incorrect SSL/TLS records once record payload
   protection is active.  ([CVE-2010-0740])

   *Bodo Moeller, Adam Langley <agl@chromium.org>*

 * Fix for CVE-2010-0433 where some kerberos enabled versions of OpenSSL
   could be crashed if the relevant tables were not present (e.g. chrooted).

   *Tomas Hoger <thoger@redhat.com>*

### Changes between 0.9.8l and 0.9.8m [25 Feb 2010]

 * Always check bn_wexpand() return values for failure.  ([CVE-2009-3245])

   *Martin Olsson, Neel Mehta*

 * Fix X509_STORE locking: Every 'objs' access requires a lock (to
   accommodate for stack sorting, always a write lock!).

   *Bodo Moeller*

 * On some versions of WIN32 Heap32Next is very slow. This can cause
   excessive delays in the RAND_poll(): over a minute. As a workaround
   include a time check in the inner Heap32Next loop too.

   *Steve Henson*

 * The code that handled flushing of data in SSL/TLS originally used the
   BIO_CTRL_INFO ctrl to see if any data was pending first. This caused
   the problem outlined in PR#1949. The fix suggested there however can
   trigger problems with buggy BIO_CTRL_WPENDING (e.g. some versions
   of Apache). So instead simplify the code to flush unconditionally.
   This should be fine since flushing with no data to flush is a no op.

   *Steve Henson*

 * Handle TLS versions 2.0 and later properly and correctly use the
   highest version of TLS/SSL supported. Although TLS >= 2.0 is some way
   off ancient servers have a habit of sticking around for a while...

   *Steve Henson*

 * Modify compression code so it frees up structures without using the
   ex_data callbacks. This works around a problem where some applications
   call CRYPTO_cleanup_all_ex_data() before application exit (e.g. when
   restarting) then use compression (e.g. SSL with compression) later.
   This results in significant per-connection memory leaks and
   has caused some security issues including CVE-2008-1678 and
   CVE-2009-4355.

   *Steve Henson*

 * Constify crypto/cast (i.e., <openssl/cast.h>): a CAST_KEY doesn't
   change when encrypting or decrypting.

   *Bodo Moeller*

 * Add option SSL_OP_LEGACY_SERVER_CONNECT which will allow clients to
   connect and renegotiate with servers which do not support RI.
   Until RI is more widely deployed this option is enabled by default.

   *Steve Henson*

 * Add "missing" ssl ctrls to clear options and mode.

   *Steve Henson*

 * If client attempts to renegotiate and doesn't support RI respond with
   a no_renegotiation alert as required by RFC5746.  Some renegotiating
   TLS clients will continue a connection gracefully when they receive
   the alert. Unfortunately OpenSSL mishandled this alert and would hang
   waiting for a server hello which it will never receive. Now we treat a
   received no_renegotiation alert as a fatal error. This is because
   applications requesting a renegotiation might well expect it to succeed
   and would have no code in place to handle the server denying it so the
   only safe thing to do is to terminate the connection.

   *Steve Henson*

 * Add ctrl macro SSL_get_secure_renegotiation_support() which returns 1 if
   peer supports secure renegotiation and 0 otherwise. Print out peer
   renegotiation support in s_client/s_server.

   *Steve Henson*

 * Replace the highly broken and deprecated SPKAC certification method with
   the updated NID creation version. This should correctly handle UTF8.

   *Steve Henson*

 * Implement RFC5746. Re-enable renegotiation but require the extension
   as needed. Unfortunately, SSL3_FLAGS_ALLOW_UNSAFE_LEGACY_RENEGOTIATION
   turns out to be a bad idea. It has been replaced by
   SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION which can be set with
   SSL_CTX_set_options(). This is really not recommended unless you
   know what you are doing.

   *Eric Rescorla <ekr@networkresonance.com>, Ben Laurie, Steve Henson*

 * Fixes to stateless session resumption handling. Use initial_ctx when
   issuing and attempting to decrypt tickets in case it has changed during
   servername handling. Use a non-zero length session ID when attempting
   stateless session resumption: this makes it possible to determine if
   a resumption has occurred immediately after receiving server hello
   (several places in OpenSSL subtly assume this) instead of later in
   the handshake.

   *Steve Henson*

 * The functions ENGINE_ctrl(), OPENSSL_isservice(),
   CMS_get1_RecipientRequest() and RAND_bytes() can return <=0 on error
   fixes for a few places where the return code is not checked
   correctly.

   *Julia Lawall <julia@diku.dk>*

 * Add --strict-warnings option to Configure script to include devteam
   warnings in other configurations.

   *Steve Henson*

 * Add support for --libdir option and LIBDIR variable in makefiles. This
   makes it possible to install openssl libraries in locations which
   have names other than "lib", for example "/usr/lib64" which some
   systems need.

   *Steve Henson, based on patch from Jeremy Utley*

 * Don't allow the use of leading 0x80 in OIDs. This is a violation of
   X690 8.9.12 and can produce some misleading textual output of OIDs.

   *Steve Henson, reported by Dan Kaminsky*

 * Delete MD2 from algorithm tables. This follows the recommendation in
   several standards that it is not used in new applications due to
   several cryptographic weaknesses. For binary compatibility reasons
   the MD2 API is still compiled in by default.

   *Steve Henson*

 * Add compression id to {d2i,i2d}_SSL_SESSION so it is correctly saved
   and restored.

   *Steve Henson*

 * Rename uni2asc and asc2uni functions to OPENSSL_uni2asc and
   OPENSSL_asc2uni conditionally on Netware platforms to avoid a name
   clash.

   *Guenter <lists@gknw.net>*

 * Fix the server certificate chain building code to use X509_verify_cert(),
   it used to have an ad-hoc builder which was unable to cope with anything
   other than a simple chain.

   *David Woodhouse <dwmw2@infradead.org>, Steve Henson*

 * Don't check self signed certificate signatures in X509_verify_cert()
   by default (a flag can override this): it just wastes time without
   adding any security. As a useful side effect self signed root CAs
   with non-FIPS digests are now usable in FIPS mode.

   *Steve Henson*

 * In dtls1_process_out_of_seq_message() the check if the current message
   is already buffered was missing. For every new message was memory
   allocated, allowing an attacker to perform an denial of service attack
   with sending out of seq handshake messages until there is no memory
   left. Additionally every future message was buffered, even if the
   sequence number made no sense and would be part of another handshake.
   So only messages with sequence numbers less than 10 in advance will be
   buffered.  ([CVE-2009-1378])

   *Robin Seggelmann, discovered by Daniel Mentz*

 * Records are buffered if they arrive with a future epoch to be
   processed after finishing the corresponding handshake. There is
   currently no limitation to this buffer allowing an attacker to perform
   a DOS attack with sending records with future epochs until there is no
   memory left. This patch adds the pqueue_size() function to determine
   the size of a buffer and limits the record buffer to 100 entries.
   ([CVE-2009-1377])

   *Robin Seggelmann, discovered by Daniel Mentz*

 * Keep a copy of frag->msg_header.frag_len so it can be used after the
   parent structure is freed.  ([CVE-2009-1379])

   *Daniel Mentz*

 * Handle non-blocking I/O properly in SSL_shutdown() call.

   *Darryl Miles <darryl-mailinglists@netbauds.net>*

 * Add `2.5.4.*` OIDs

   *Ilya O. <vrghost@gmail.com>*

### Changes between 0.9.8k and 0.9.8l  [5 Nov 2009]

 * Disable renegotiation completely - this fixes a severe security
   problem ([CVE-2009-3555]) at the cost of breaking all
   renegotiation. Renegotiation can be re-enabled by setting
   SSL3_FLAGS_ALLOW_UNSAFE_LEGACY_RENEGOTIATION in s3->flags at
   run-time. This is really not recommended unless you know what
   you're doing.

   *Ben Laurie*

### Changes between 0.9.8j and 0.9.8k  [25 Mar 2009]

 * Don't set val to NULL when freeing up structures, it is freed up by
   underlying code. If `sizeof(void *) > sizeof(long)` this can result in
   zeroing past the valid field. ([CVE-2009-0789])

   *Paolo Ganci <Paolo.Ganci@AdNovum.CH>*

 * Fix bug where return value of CMS_SignerInfo_verify_content() was not
   checked correctly. This would allow some invalid signed attributes to
   appear to verify correctly. ([CVE-2009-0591])

   *Ivan Nestlerode <inestlerode@us.ibm.com>*

 * Reject UniversalString and BMPString types with invalid lengths. This
   prevents a crash in ASN1_STRING_print_ex() which assumes the strings have
   a legal length. ([CVE-2009-0590])

   *Steve Henson*

 * Set S/MIME signing as the default purpose rather than setting it
   unconditionally. This allows applications to override it at the store
   level.

   *Steve Henson*

 * Permit restricted recursion of ASN1 strings. This is needed in practice
   to handle some structures.

   *Steve Henson*

 * Improve efficiency of mem_gets: don't search whole buffer each time
   for a '\n'

   *Jeremy Shapiro <jnshapir@us.ibm.com>*

 * New -hex option for openssl rand.

   *Matthieu Herrb*

 * Print out UTF8String and NumericString when parsing ASN1.

   *Steve Henson*

 * Support NumericString type for name components.

   *Steve Henson*

 * Allow CC in the environment to override the automatically chosen
   compiler. Note that nothing is done to ensure flags work with the
   chosen compiler.

   *Ben Laurie*

### Changes between 0.9.8i and 0.9.8j  [07 Jan 2009]

 * Properly check EVP_VerifyFinal() and similar return values
   ([CVE-2008-5077]).

   *Ben Laurie, Bodo Moeller, Google Security Team*

 * Enable TLS extensions by default.

   *Ben Laurie*

 * Allow the CHIL engine to be loaded, whether the application is
   multithreaded or not. (This does not release the developer from the
   obligation to set up the dynamic locking callbacks.)

   *Sander Temme <sander@temme.net>*

 * Use correct exit code if there is an error in dgst command.

   *Steve Henson; problem pointed out by Roland Dirlewanger*

 * Tweak Configure so that you need to say "experimental-jpake" to enable
   JPAKE, and need to use -DOPENSSL_EXPERIMENTAL_JPAKE in applications.

   *Bodo Moeller*

 * Add experimental JPAKE support, including demo authentication in
   s_client and s_server.

   *Ben Laurie*

 * Set the comparison function in v3_addr_canonize().

   *Rob Austein <sra@hactrn.net>*

 * Add support for XMPP STARTTLS in s_client.

   *Philip Paeps <philip@freebsd.org>*

 * Change the server-side SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG behavior
   to ensure that even with this option, only ciphersuites in the
   server's preference list will be accepted.  (Note that the option
   applies only when resuming a session, so the earlier behavior was
   just about the algorithm choice for symmetric cryptography.)

   *Bodo Moeller*

### Changes between 0.9.8h and 0.9.8i  [15 Sep 2008]

 * Fix NULL pointer dereference if a DTLS server received
   ChangeCipherSpec as first record ([CVE-2009-1386]).

   *PR #1679*

 * Fix a state transition in s3_srvr.c and d1_srvr.c
   (was using SSL3_ST_CW_CLNT_HELLO_B, should be `..._ST_SW_SRVR_...`).

   *Nagendra Modadugu*

 * The fix in 0.9.8c that supposedly got rid of unsafe
   double-checked locking was incomplete for RSA blinding,
   addressing just one layer of what turns out to have been
   doubly unsafe triple-checked locking.

   So now fix this for real by retiring the MONT_HELPER macro
   in crypto/rsa/rsa_eay.c.

   *Bodo Moeller; problem pointed out by Marius Schilder*

 * Various precautionary measures:

   - Avoid size_t integer overflow in HASH_UPDATE (md32_common.h).

   - Avoid a buffer overflow in d2i_SSL_SESSION() (ssl_asn1.c).
     (NB: This would require knowledge of the secret session ticket key
     to exploit, in which case you'd be SOL either way.)

   - Change bn_nist.c so that it will properly handle input BIGNUMs
     outside the expected range.

   - Enforce the 'num' check in BN_div() (bn_div.c) for non-BN_DEBUG
     builds.

   *Neel Mehta, Bodo Moeller*

 * Allow engines to be "soft loaded" - i.e. optionally don't die if
   the load fails. Useful for distros.

   *Ben Laurie and the FreeBSD team*

 * Add support for Local Machine Keyset attribute in PKCS#12 files.

   *Steve Henson*

 * Fix BN_GF2m_mod_arr() top-bit cleanup code.

   *Huang Ying*

 * Expand ENGINE to support engine supplied SSL client certificate functions.

   This work was sponsored by Logica.

   *Steve Henson*

 * Add CryptoAPI ENGINE to support use of RSA and DSA keys held in Windows
   keystores. Support for SSL/TLS client authentication too.
   Not compiled unless enable-capieng specified to Configure.

   This work was sponsored by Logica.

   *Steve Henson*

 * Fix bug in X509_ATTRIBUTE creation: don't set attribute using
   ASN1_TYPE_set1 if MBSTRING flag set. This bug would crash certain
   attribute creation routines such as certificate requests and PKCS#12
   files.

   *Steve Henson*

### Changes between 0.9.8g and 0.9.8h  [28 May 2008]

 * Fix flaw if 'Server Key exchange message' is omitted from a TLS
   handshake which could lead to a client crash as found using the
   Codenomicon TLS test suite ([CVE-2008-1672])

   *Steve Henson, Mark Cox*

 * Fix double free in TLS server name extensions which could lead to
   a remote crash found by Codenomicon TLS test suite ([CVE-2008-0891])

   *Joe Orton*

 * Clear error queue in SSL_CTX_use_certificate_chain_file()

   Clear the error queue to ensure that error entries left from
   older function calls do not interfere with the correct operation.

   *Lutz Jaenicke, Erik de Castro Lopo*

 * Remove root CA certificates of commercial CAs:

   The OpenSSL project does not recommend any specific CA and does not
   have any policy with respect to including or excluding any CA.
   Therefore, it does not make any sense to ship an arbitrary selection
   of root CA certificates with the OpenSSL software.

   *Lutz Jaenicke*

 * RSA OAEP patches to fix two separate invalid memory reads.
   The first one involves inputs when 'lzero' is greater than
   'SHA_DIGEST_LENGTH' (it would read about SHA_DIGEST_LENGTH bytes
   before the beginning of from). The second one involves inputs where
   the 'db' section contains nothing but zeroes (there is a one-byte
   invalid read after the end of 'db').

   *Ivan Nestlerode <inestlerode@us.ibm.com>*

 * Partial backport from 0.9.9-dev:

   Introduce bn_mul_mont (dedicated Montgomery multiplication
   procedure) as a candidate for BIGNUM assembler implementation.
   While 0.9.9-dev uses assembler for various architectures, only
   x86_64 is available by default here in the 0.9.8 branch, and
   32-bit x86 is available through a compile-time setting.

   To try the 32-bit x86 assembler implementation, use Configure
   option "enable-montasm" (which exists only for this backport).

   As "enable-montasm" for 32-bit x86 disclaims code stability
   anyway, in this constellation we activate additional code
   backported from 0.9.9-dev for further performance improvements,
   namely BN_from_montgomery_word.  (To enable this otherwise,
   e.g. x86_64, try `-DMONT_FROM_WORD___NON_DEFAULT_0_9_8_BUILD`.)

   *Andy Polyakov (backport partially by Bodo Moeller)*

 * Add TLS session ticket callback. This allows an application to set
   TLS ticket cipher and HMAC keys rather than relying on hardcoded fixed
   values. This is useful for key rollover for example where several key
   sets may exist with different names.

   *Steve Henson*

 * Reverse ENGINE-internal logic for caching default ENGINE handles.
   This was broken until now in 0.9.8 releases, such that the only way
   a registered ENGINE could be used (assuming it initialises
   successfully on the host) was to explicitly set it as the default
   for the relevant algorithms. This is in contradiction with 0.9.7
   behaviour and the documentation. With this fix, when an ENGINE is
   registered into a given algorithm's table of implementations, the
   'uptodate' flag is reset so that auto-discovery will be used next
   time a new context for that algorithm attempts to select an
   implementation.

   *Ian Lister (tweaked by Geoff Thorpe)*

 * Backport of CMS code to OpenSSL 0.9.8. This differs from the 0.9.9
   implementation in the following ways:

   Lack of EVP_PKEY_ASN1_METHOD means algorithm parameters have to be
   hard coded.

   Lack of BER streaming support means one pass streaming processing is
   only supported if data is detached: setting the streaming flag is
   ignored for embedded content.

   CMS support is disabled by default and must be explicitly enabled
   with the enable-cms configuration option.

   *Steve Henson*

 * Update the GMP engine glue to do direct copies between BIGNUM and
   mpz_t when openssl and GMP use the same limb size. Otherwise the
   existing "conversion via a text string export" trick is still used.

   *Paul Sheer <paulsheer@gmail.com>*

 * Zlib compression BIO. This is a filter BIO which compressed and
   uncompresses any data passed through it.

   *Steve Henson*

 * Add AES_wrap_key() and AES_unwrap_key() functions to implement
   RFC3394 compatible AES key wrapping.

   *Steve Henson*

 * Add utility functions to handle ASN1 structures. ASN1_STRING_set0():
   sets string data without copying. X509_ALGOR_set0() and
   X509_ALGOR_get0(): set and retrieve X509_ALGOR (AlgorithmIdentifier)
   data. Attribute function X509at_get0_data_by_OBJ(): retrieves data
   from an X509_ATTRIBUTE structure optionally checking it occurs only
   once. ASN1_TYPE_set1(): set and ASN1_TYPE structure copying supplied
   data.

   *Steve Henson*

 * Fix BN flag handling in RSA_eay_mod_exp() and BN_MONT_CTX_set()
   to get the expected BN_FLG_CONSTTIME behavior.

   *Bodo Moeller (Google)*

 * Netware support:

   - fixed wrong usage of ioctlsocket() when build for LIBC BSD sockets
   - fixed do_tests.pl to run the test suite with CLIB builds too (CLIB_OPT)
   - added some more tests to do_tests.pl
   - fixed RunningProcess usage so that it works with newer LIBC NDKs too
   - removed usage of BN_LLONG for CLIB builds to avoid runtime dependency
   - added new Configure targets netware-clib-bsdsock, netware-clib-gcc,
     netware-clib-bsdsock-gcc, netware-libc-bsdsock-gcc
   - various changes to netware.pl to enable gcc-cross builds on Win32
     platform
   - changed crypto/bio/b_sock.c to work with macro functions (CLIB BSD)
   - various changes to fix missing prototype warnings
   - fixed x86nasm.pl to create correct asm files for NASM COFF output
   - added AES, WHIRLPOOL and CPUID assembler code to build files
   - added missing AES assembler make rules to mk1mf.pl
   - fixed order of includes in `apps/ocsp.c` so that `e_os.h` settings apply

   *Guenter Knauf <eflash@gmx.net>*

 * Implement certificate status request TLS extension defined in RFC3546.
   A client can set the appropriate parameters and receive the encoded
   OCSP response via a callback. A server can query the supplied parameters
   and set the encoded OCSP response in the callback. Add simplified examples
   to s_client and s_server.

   *Steve Henson*

### Changes between 0.9.8f and 0.9.8g  [19 Oct 2007]

 * Fix various bugs:
   + Binary incompatibility of ssl_ctx_st structure
   + DTLS interoperation with non-compliant servers
   + Don't call get_session_cb() without proposed session
   + Fix ia64 assembler code

   *Andy Polyakov, Steve Henson*

### Changes between 0.9.8e and 0.9.8f  [11 Oct 2007]

 * DTLS Handshake overhaul. There were longstanding issues with
   OpenSSL DTLS implementation, which were making it impossible for
   RFC 4347 compliant client to communicate with OpenSSL server.
   Unfortunately just fixing these incompatibilities would "cut off"
   pre-0.9.8f clients. To allow for hassle free upgrade post-0.9.8e
   server keeps tolerating non RFC compliant syntax. The opposite is
   not true, 0.9.8f client can not communicate with earlier server.
   This update even addresses CVE-2007-4995.

   *Andy Polyakov*

 * Changes to avoid need for function casts in OpenSSL: some compilers
   (gcc 4.2 and later) reject their use.
   *Kurt Roeckx <kurt@roeckx.be>, Peter Hartley <pdh@utter.chaos.org.uk>,
    Steve Henson*

 * Add RFC4507 support to OpenSSL. This includes the corrections in
   RFC4507bis. The encrypted ticket format is an encrypted encoded
   SSL_SESSION structure, that way new session features are automatically
   supported.

   If a client application caches session in an SSL_SESSION structure
   support is transparent because tickets are now stored in the encoded
   SSL_SESSION.

   The SSL_CTX structure automatically generates keys for ticket
   protection in servers so again support should be possible
   with no application modification.

   If a client or server wishes to disable RFC4507 support then the option
   SSL_OP_NO_TICKET can be set.

   Add a TLS extension debugging callback to allow the contents of any client
   or server extensions to be examined.

   This work was sponsored by Google.

   *Steve Henson*

 * Add initial support for TLS extensions, specifically for the server_name
   extension so far.  The SSL_SESSION, SSL_CTX, and SSL data structures now
   have new members for a hostname.  The SSL data structure has an
   additional member `SSL_CTX *initial_ctx` so that new sessions can be
   stored in that context to allow for session resumption, even after the
   SSL has been switched to a new SSL_CTX in reaction to a client's
   server_name extension.

   New functions (subject to change):

           SSL_get_servername()
           SSL_get_servername_type()
           SSL_set_SSL_CTX()

   New CTRL codes and macros (subject to change):

           SSL_CTRL_SET_TLSEXT_SERVERNAME_CB
                               - SSL_CTX_set_tlsext_servername_callback()
           SSL_CTRL_SET_TLSEXT_SERVERNAME_ARG
                                    - SSL_CTX_set_tlsext_servername_arg()
           SSL_CTRL_SET_TLSEXT_HOSTNAME           - SSL_set_tlsext_host_name()

   openssl s_client has a new '-servername ...' option.

   openssl s_server has new options '-servername_host ...', '-cert2 ...',
   '-key2 ...', '-servername_fatal' (subject to change).  This allows
   testing the HostName extension for a specific single hostname ('-cert'
   and '-key' remain fallbacks for handshakes without HostName
   negotiation).  If the unrecognized_name alert has to be sent, this by
   default is a warning; it becomes fatal with the '-servername_fatal'
   option.

   *Peter Sylvester,  Remy Allais, Christophe Renou, Steve Henson*

 * Add AES and SSE2 assembly language support to VC++ build.

   *Steve Henson*

 * Mitigate attack on final subtraction in Montgomery reduction.

   *Andy Polyakov*

 * Fix crypto/ec/ec_mult.c to work properly with scalars of value 0
   (which previously caused an internal error).

   *Bodo Moeller*

 * Squeeze another 10% out of IGE mode when in != out.

   *Ben Laurie*

 * AES IGE mode speedup.

   *Dean Gaudet (Google)*

 * Add the Korean symmetric 128-bit cipher SEED (see
   <http://www.kisa.or.kr/kisa/seed/jsp/seed_eng.jsp>) and
   add SEED ciphersuites from RFC 4162:

           TLS_RSA_WITH_SEED_CBC_SHA      =  "SEED-SHA"
           TLS_DHE_DSS_WITH_SEED_CBC_SHA  =  "DHE-DSS-SEED-SHA"
           TLS_DHE_RSA_WITH_SEED_CBC_SHA  =  "DHE-RSA-SEED-SHA"
           TLS_DH_anon_WITH_SEED_CBC_SHA  =  "ADH-SEED-SHA"

   To minimize changes between patchlevels in the OpenSSL 0.9.8
   series, SEED remains excluded from compilation unless OpenSSL
   is configured with 'enable-seed'.

   *KISA, Bodo Moeller*

 * Mitigate branch prediction attacks, which can be practical if a
   single processor is shared, allowing a spy process to extract
   information.  For detailed background information, see
   <http://eprint.iacr.org/2007/039> (O. Aciicmez, S. Gueron,
   J.-P. Seifert, "New Branch Prediction Vulnerabilities in OpenSSL
   and Necessary Software Countermeasures").  The core of the change
   are new versions BN_div_no_branch() and
   BN_mod_inverse_no_branch() of BN_div() and BN_mod_inverse(),
   respectively, which are slower, but avoid the security-relevant
   conditional branches.  These are automatically called by BN_div()
   and BN_mod_inverse() if the flag BN_FLG_CONSTTIME is set for one
   of the input BIGNUMs.  Also, BN_is_bit_set() has been changed to
   remove a conditional branch.

   BN_FLG_CONSTTIME is the new name for the previous
   BN_FLG_EXP_CONSTTIME flag, since it now affects more than just
   modular exponentiation.  (Since OpenSSL 0.9.7h, setting this flag
   in the exponent causes BN_mod_exp_mont() to use the alternative
   implementation in BN_mod_exp_mont_consttime().)  The old name
   remains as a deprecated alias.

   Similarly, RSA_FLAG_NO_EXP_CONSTTIME is replaced by a more general
   RSA_FLAG_NO_CONSTTIME flag since the RSA implementation now uses
   constant-time implementations for more than just exponentiation.
   Here too the old name is kept as a deprecated alias.

   BN_BLINDING_new() will now use BN_dup() for the modulus so that
   the BN_BLINDING structure gets an independent copy of the
   modulus.  This means that the previous `BIGNUM *m` argument to
   BN_BLINDING_new() and to BN_BLINDING_create_param() now
   essentially becomes `const BIGNUM *m`, although we can't actually
   change this in the header file before 0.9.9.  It allows
   RSA_setup_blinding() to use BN_with_flags() on the modulus to
   enable BN_FLG_CONSTTIME.

   *Matthew D Wood (Intel Corp)*

 * In the SSL/TLS server implementation, be strict about session ID
   context matching (which matters if an application uses a single
   external cache for different purposes).  Previously,
   out-of-context reuse was forbidden only if SSL_VERIFY_PEER was
   set.  This did ensure strict client verification, but meant that,
   with applications using a single external cache for quite
   different requirements, clients could circumvent ciphersuite
   restrictions for a given session ID context by starting a session
   in a different context.

   *Bodo Moeller*

 * Include "!eNULL" in SSL_DEFAULT_CIPHER_LIST to make sure that
   a ciphersuite string such as "DEFAULT:RSA" cannot enable
   authentication-only ciphersuites.

   *Bodo Moeller*

 * Update the SSL_get_shared_ciphers() fix CVE-2006-3738 which was
   not complete and could lead to a possible single byte overflow
   ([CVE-2007-5135]) [Ben Laurie]

### Changes between 0.9.8d and 0.9.8e  [23 Feb 2007]

 * Since AES128 and AES256 (and similarly Camellia128 and
   Camellia256) share a single mask bit in the logic of
   ssl/ssl_ciph.c, the code for masking out disabled ciphers needs a
   kludge to work properly if AES128 is available and AES256 isn't
   (or if Camellia128 is available and Camellia256 isn't).

   *Victor Duchovni*

 * Fix the BIT STRING encoding generated by crypto/ec/ec_asn1.c
   (within i2d_ECPrivateKey, i2d_ECPKParameters, i2d_ECParameters):
   When a point or a seed is encoded in a BIT STRING, we need to
   prevent the removal of trailing zero bits to get the proper DER
   encoding.  (By default, crypto/asn1/a_bitstr.c assumes the case
   of a NamedBitList, for which trailing 0 bits need to be removed.)

   *Bodo Moeller*

 * Have SSL/TLS server implementation tolerate "mismatched" record
   protocol version while receiving ClientHello even if the
   ClientHello is fragmented.  (The server can't insist on the
   particular protocol version it has chosen before the ServerHello
   message has informed the client about his choice.)

   *Bodo Moeller*

 * Add RFC 3779 support.

   *Rob Austein for ARIN, Ben Laurie*

 * Load error codes if they are not already present instead of using a
   static variable. This allows them to be cleanly unloaded and reloaded.
   Improve header file function name parsing.

   *Steve Henson*

 * extend SMTP and IMAP protocol emulation in s_client to use EHLO
   or CAPABILITY handshake as required by RFCs.

   *Goetz Babin-Ebell*

### Changes between 0.9.8c and 0.9.8d  [28 Sep 2006]

 * Introduce limits to prevent malicious keys being able to
   cause a denial of service.  ([CVE-2006-2940])

   *Steve Henson, Bodo Moeller*

 * Fix ASN.1 parsing of certain invalid structures that can result
   in a denial of service.  ([CVE-2006-2937])  [Steve Henson]

 * Fix buffer overflow in SSL_get_shared_ciphers() function.
   ([CVE-2006-3738]) [Tavis Ormandy and Will Drewry, Google Security Team]

 * Fix SSL client code which could crash if connecting to a
   malicious SSLv2 server.  ([CVE-2006-4343])

   *Tavis Ormandy and Will Drewry, Google Security Team*

 * Since 0.9.8b, ciphersuite strings naming explicit ciphersuites
   match only those.  Before that, "AES256-SHA" would be interpreted
   as a pattern and match "AES128-SHA" too (since AES128-SHA got
   the same strength classification in 0.9.7h) as we currently only
   have a single AES bit in the ciphersuite description bitmap.
   That change, however, also applied to ciphersuite strings such as
   "RC4-MD5" that intentionally matched multiple ciphersuites --
   namely, SSL 2.0 ciphersuites in addition to the more common ones
   from SSL 3.0/TLS 1.0.

   So we change the selection algorithm again: Naming an explicit
   ciphersuite selects this one ciphersuite, and any other similar
   ciphersuite (same bitmap) from *other* protocol versions.
   Thus, "RC4-MD5" again will properly select both the SSL 2.0
   ciphersuite and the SSL 3.0/TLS 1.0 ciphersuite.

   Since SSL 2.0 does not have any ciphersuites for which the
   128/256 bit distinction would be relevant, this works for now.
   The proper fix will be to use different bits for AES128 and
   AES256, which would have avoided the problems from the beginning;
   however, bits are scarce, so we can only do this in a new release
   (not just a patchlevel) when we can change the SSL_CIPHER
   definition to split the single 'unsigned long mask' bitmap into
   multiple values to extend the available space.

   *Bodo Moeller*

### Changes between 0.9.8b and 0.9.8c  [05 Sep 2006]

 * Avoid PKCS #1 v1.5 signature attack discovered by Daniel Bleichenbacher
   ([CVE-2006-4339])  [Ben Laurie and Google Security Team]

 * Add AES IGE and biIGE modes.

   *Ben Laurie*

 * Change the Unix randomness entropy gathering to use poll() when
   possible instead of select(), since the latter has some
   undesirable limitations.

   *Darryl Miles via Richard Levitte and Bodo Moeller*

 * Disable "ECCdraft" ciphersuites more thoroughly.  Now special
   treatment in ssl/ssl_ciph.s makes sure that these ciphersuites
   cannot be implicitly activated as part of, e.g., the "AES" alias.
   However, please upgrade to OpenSSL 0.9.9[-dev] for
   non-experimental use of the ECC ciphersuites to get TLS extension
   support, which is required for curve and point format negotiation
   to avoid potential handshake problems.

   *Bodo Moeller*

 * Disable rogue ciphersuites:

   - SSLv2 0x08 0x00 0x80 ("RC4-64-MD5")
   - SSLv3/TLSv1 0x00 0x61 ("EXP1024-RC2-CBC-MD5")
   - SSLv3/TLSv1 0x00 0x60 ("EXP1024-RC4-MD5")

   The latter two were purportedly from
   draft-ietf-tls-56-bit-ciphersuites-0[01].txt, but do not really
   appear there.

   Also deactivate the remaining ciphersuites from
   draft-ietf-tls-56-bit-ciphersuites-01.txt.  These are just as
   unofficial, and the ID has long expired.

   *Bodo Moeller*

 * Fix RSA blinding Heisenbug (problems sometimes occurred on
   dual-core machines) and other potential thread-safety issues.

   *Bodo Moeller*

 * Add the symmetric cipher Camellia (128-bit, 192-bit, 256-bit key
   versions), which is now available for royalty-free use
   (see <http://info.isl.ntt.co.jp/crypt/eng/info/chiteki.html>).
   Also, add Camellia TLS ciphersuites from RFC 4132.

   To minimize changes between patchlevels in the OpenSSL 0.9.8
   series, Camellia remains excluded from compilation unless OpenSSL
   is configured with 'enable-camellia'.

   *NTT*

 * Disable the padding bug check when compression is in use. The padding
   bug check assumes the first packet is of even length, this is not
   necessarily true if compression is enabled and can result in false
   positives causing handshake failure. The actual bug test is ancient
   code so it is hoped that implementations will either have fixed it by
   now or any which still have the bug do not support compression.

   *Steve Henson*

### Changes between 0.9.8a and 0.9.8b  [04 May 2006]

 * When applying a cipher rule check to see if string match is an explicit
   cipher suite and only match that one cipher suite if it is.

   *Steve Henson*

 * Link in manifests for VC++ if needed.

   *Austin Ziegler <halostatue@gmail.com>*

 * Update support for ECC-based TLS ciphersuites according to
   draft-ietf-tls-ecc-12.txt with proposed changes (but without
   TLS extensions, which are supported starting with the 0.9.9
   branch, not in the OpenSSL 0.9.8 branch).

   *Douglas Stebila*

 * New functions EVP_CIPHER_CTX_new() and EVP_CIPHER_CTX_free() to support
   opaque EVP_CIPHER_CTX handling.

   *Steve Henson*

 * Fixes and enhancements to zlib compression code. We now only use
   "zlib1.dll" and use the default `__cdecl` calling convention on Win32
   to conform with the standards mentioned here:
   <http://www.zlib.net/DLL_FAQ.txt>
   Static zlib linking now works on Windows and the new --with-zlib-include
   --with-zlib-lib options to Configure can be used to supply the location
   of the headers and library. Gracefully handle case where zlib library
   can't be loaded.

   *Steve Henson*

 * Several fixes and enhancements to the OID generation code. The old code
   sometimes allowed invalid OIDs (1.X for X >= 40 for example), couldn't
   handle numbers larger than ULONG_MAX, truncated printing and had a
   non standard OBJ_obj2txt() behaviour.

   *Steve Henson*

 * Add support for building of engines under engine/ as shared libraries
   under VC++ build system.

   *Steve Henson*

 * Corrected the numerous bugs in the Win32 path splitter in DSO.
   Hopefully, we will not see any false combination of paths any more.

   *Richard Levitte*

### Changes between 0.9.8 and 0.9.8a  [11 Oct 2005]

 * Remove the functionality of SSL_OP_MSIE_SSLV2_RSA_PADDING
   (part of SSL_OP_ALL).  This option used to disable the
   countermeasure against man-in-the-middle protocol-version
   rollback in the SSL 2.0 server implementation, which is a bad
   idea.  ([CVE-2005-2969])

   *Bodo Moeller; problem pointed out by Yutaka Oiwa (Research Center
   for Information Security, National Institute of Advanced Industrial
   Science and Technology [AIST], Japan)*

 * Add two function to clear and return the verify parameter flags.

   *Steve Henson*

 * Keep cipherlists sorted in the source instead of sorting them at
   runtime, thus removing the need for a lock.

   *Nils Larsch*

 * Avoid some small subgroup attacks in Diffie-Hellman.

   *Nick Mathewson and Ben Laurie*

 * Add functions for well-known primes.

   *Nick Mathewson*

 * Extended Windows CE support.

   *Satoshi Nakamura and Andy Polyakov*

 * Initialize SSL_METHOD structures at compile time instead of during
   runtime, thus removing the need for a lock.

   *Steve Henson*

 * Make PKCS7_decrypt() work even if no certificate is supplied by
   attempting to decrypt each encrypted key in turn. Add support to
   smime utility.

   *Steve Henson*

### Changes between 0.9.7h and 0.9.8  [05 Jul 2005]

[NB: OpenSSL 0.9.7i and later 0.9.7 patch levels were released after
OpenSSL 0.9.8.]

 * Add libcrypto.pc and libssl.pc for those who feel they need them.

   *Richard Levitte*

 * Change CA.sh and CA.pl so they don't bundle the CSR and the private
   key into the same file any more.

   *Richard Levitte*

 * Add initial support for Win64, both IA64 and AMD64/x64 flavors.

   *Andy Polyakov*

 * Add -utf8 command line and config file option to 'ca'.

   *Stefan <stf@udoma.org*

 * Removed the macro des_crypt(), as it seems to conflict with some
   libraries.  Use DES_crypt().

   *Richard Levitte*

 * Correct naming of the 'chil' and '4758cca' ENGINEs. This
   involves renaming the source and generated shared-libs for
   both. The engines will accept the corrected or legacy ids
   ('ncipher' and '4758_cca' respectively) when binding. NB,
   this only applies when building 'shared'.

   *Corinna Vinschen <vinschen@redhat.com> and Geoff Thorpe*

 * Add attribute functions to EVP_PKEY structure. Modify
   PKCS12_create() to recognize a CSP name attribute and
   use it. Make -CSP option work again in pkcs12 utility.

   *Steve Henson*

 * Add new functionality to the bn blinding code:
   - automatic re-creation of the BN_BLINDING parameters after
     a fixed number of uses (currently 32)
   - add new function for parameter creation
   - introduce flags to control the update behaviour of the
     BN_BLINDING parameters
   - hide BN_BLINDING structure
   Add a second BN_BLINDING slot to the RSA structure to improve
   performance when a single RSA object is shared among several
   threads.

   *Nils Larsch*

 * Add support for DTLS.

   *Nagendra Modadugu <nagendra@cs.stanford.edu> and Ben Laurie*

 * Add support for DER encoded private keys (SSL_FILETYPE_ASN1)
   to SSL_CTX_use_PrivateKey_file() and SSL_use_PrivateKey_file()

   *Walter Goulet*

 * Remove buggy and incomplete DH cert support from
   ssl/ssl_rsa.c and ssl/s3_both.c

   *Nils Larsch*

 * Use SHA-1 instead of MD5 as the default digest algorithm for
   the `apps/openssl` commands.

   *Nils Larsch*

 * Compile clean with "-Wall -Wmissing-prototypes
   -Wstrict-prototypes -Wmissing-declarations -Werror". Currently
   DEBUG_SAFESTACK must also be set.

   *Ben Laurie*

 * Change ./Configure so that certain algorithms can be disabled by default.
   The new counterpiece to "no-xxx" is "enable-xxx".

   The patented RC5 and MDC2 algorithms will now be disabled unless
   "enable-rc5" and "enable-mdc2", respectively, are specified.

   (IDEA remains enabled despite being patented.  This is because IDEA
   is frequently required for interoperability, and there is no license
   fee for non-commercial use.  As before, "no-idea" can be used to
   avoid this algorithm.)

   *Bodo Moeller*

 * Add processing of proxy certificates (see RFC 3820).  This work was
   sponsored by KTH (The Royal Institute of Technology in Stockholm) and
   EGEE (Enabling Grids for E-science in Europe).

   *Richard Levitte*

 * RC4 performance overhaul on modern architectures/implementations, such
   as Intel P4, IA-64 and AMD64.

   *Andy Polyakov*

 * New utility extract-section.pl. This can be used specify an alternative
   section number in a pod file instead of having to treat each file as
   a separate case in Makefile. This can be done by adding two lines to the
   pod file:

   =for comment openssl_section:XXX

   The blank line is mandatory.

   *Steve Henson*

 * New arguments -certform, -keyform and -pass for s_client and s_server
   to allow alternative format key and certificate files and passphrase
   sources.

   *Steve Henson*

 * New structure X509_VERIFY_PARAM which combines current verify parameters,
   update associated structures and add various utility functions.

   Add new policy related verify parameters, include policy checking in
   standard verify code. Enhance 'smime' application with extra parameters
   to support policy checking and print out.

   *Steve Henson*

 * Add a new engine to support VIA PadLock ACE extensions in the VIA C3
   Nehemiah processors. These extensions support AES encryption in hardware
   as well as RNG (though RNG support is currently disabled).

   *Michal Ludvig <michal@logix.cz>, with help from Andy Polyakov*

 * Deprecate `BN_[get|set]_params()` functions (they were ignored internally).

   *Geoff Thorpe*

 * New FIPS 180-2 algorithms, SHA-224/-256/-384/-512 are implemented.

   *Andy Polyakov and a number of other people*

 * Improved PowerPC platform support. Most notably BIGNUM assembler
   implementation contributed by IBM.

   *Suresh Chari, Peter Waltenberg, Andy Polyakov*

 * The new 'RSA_generate_key_ex' function now takes a BIGNUM for the public
   exponent rather than 'unsigned long'. There is a corresponding change to
   the new 'rsa_keygen' element of the RSA_METHOD structure.

   *Jelte Jansen, Geoff Thorpe*

 * Functionality for creating the initial serial number file is now
   moved from CA.pl to the 'ca' utility with a new option -create_serial.

   (Before OpenSSL 0.9.7e, CA.pl used to initialize the serial
   number file to 1, which is bound to cause problems.  To avoid
   the problems while respecting compatibility between different 0.9.7
   patchlevels, 0.9.7e  employed 'openssl x509 -next_serial' in
   CA.pl for serial number initialization.  With the new release 0.9.8,
   we can fix the problem directly in the 'ca' utility.)

   *Steve Henson*

 * Reduced header interdependencies by declaring more opaque objects in
   ossl_typ.h. As a consequence, including some headers (eg. engine.h) will
   give fewer recursive includes, which could break lazy source code - so
   this change is covered by the OPENSSL_NO_DEPRECATED symbol. As always,
   developers should define this symbol when building and using openssl to
   ensure they track the recommended behaviour, interfaces, [etc], but
   backwards-compatible behaviour prevails when this isn't defined.

   *Geoff Thorpe*

 * New function X509_POLICY_NODE_print() which prints out policy nodes.

   *Steve Henson*

 * Add new EVP function EVP_CIPHER_CTX_rand_key and associated functionality.
   This will generate a random key of the appropriate length based on the
   cipher context. The EVP_CIPHER can provide its own random key generation
   routine to support keys of a specific form. This is used in the des and
   3des routines to generate a key of the correct parity. Update S/MIME
   code to use new functions and hence generate correct parity DES keys.
   Add EVP_CHECK_DES_KEY #define to return an error if the key is not
   valid (weak or incorrect parity).

   *Steve Henson*

 * Add a local set of CRLs that can be used by X509_verify_cert() as well
   as looking them up. This is useful when the verified structure may contain
   CRLs, for example PKCS#7 signedData. Modify PKCS7_verify() to use any CRLs
   present unless the new PKCS7_NO_CRL flag is asserted.

   *Steve Henson*

 * Extend ASN1 oid configuration module. It now additionally accepts the
   syntax:

   shortName = some long name, 1.2.3.4

   *Steve Henson*

 * Reimplemented the BN_CTX implementation. There is now no more static
   limitation on the number of variables it can handle nor the depth of the
   "stack" handling for BN_CTX_start()/BN_CTX_end() pairs. The stack
   information can now expand as required, and rather than having a single
   static array of bignums, BN_CTX now uses a linked-list of such arrays
   allowing it to expand on demand whilst maintaining the usefulness of
   BN_CTX's "bundling".

   *Geoff Thorpe*

 * Add a missing BN_CTX parameter to the 'rsa_mod_exp' callback in RSA_METHOD
   to allow all RSA operations to function using a single BN_CTX.

   *Geoff Thorpe*

 * Preliminary support for certificate policy evaluation and checking. This
   is initially intended to pass the tests outlined in "Conformance Testing
   of Relying Party Client Certificate Path Processing Logic" v1.07.

   *Steve Henson*

 * bn_dup_expand() has been deprecated, it was introduced in 0.9.7 and
   remained unused and not that useful. A variety of other little bignum
   tweaks and fixes have also been made continuing on from the audit (see
   below).

   *Geoff Thorpe*

 * Constify all or almost all d2i, c2i, s2i and r2i functions, along with
   associated ASN1, EVP and SSL functions and old ASN1 macros.

   *Richard Levitte*

 * BN_zero() only needs to set 'top' and 'neg' to zero for correct results,
   and this should never fail. So the return value from the use of
   BN_set_word() (which can fail due to needless expansion) is now deprecated;
   if OPENSSL_NO_DEPRECATED is defined, BN_zero() is a void macro.

   *Geoff Thorpe*

 * BN_CTX_get() should return zero-valued bignums, providing the same
   initialised value as BN_new().

   *Geoff Thorpe, suggested by Ulf Möller*

 * Support for inhibitAnyPolicy certificate extension.

   *Steve Henson*

 * An audit of the BIGNUM code is underway, for which debugging code is
   enabled when BN_DEBUG is defined. This makes stricter enforcements on what
   is considered valid when processing BIGNUMs, and causes execution to
   assert() when a problem is discovered. If BN_DEBUG_RAND is defined,
   further steps are taken to deliberately pollute unused data in BIGNUM
   structures to try and expose faulty code further on. For now, openssl will
   (in its default mode of operation) continue to tolerate the inconsistent
   forms that it has tolerated in the past, but authors and packagers should
   consider trying openssl and their own applications when compiled with
   these debugging symbols defined. It will help highlight potential bugs in
   their own code, and will improve the test coverage for OpenSSL itself. At
   some point, these tighter rules will become openssl's default to improve
   maintainability, though the assert()s and other overheads will remain only
   in debugging configurations. See bn.h for more details.

   *Geoff Thorpe, Nils Larsch, Ulf Möller*

 * BN_CTX_init() has been deprecated, as BN_CTX is an opaque structure
   that can only be obtained through BN_CTX_new() (which implicitly
   initialises it). The presence of this function only made it possible
   to overwrite an existing structure (and cause memory leaks).

   *Geoff Thorpe*

 * Because of the callback-based approach for implementing LHASH as a
   template type, lh_insert() adds opaque objects to hash-tables and
   lh_doall() or lh_doall_arg() are typically used with a destructor callback
   to clean up those corresponding objects before destroying the hash table
   (and losing the object pointers). So some over-zealous constifications in
   LHASH have been relaxed so that lh_insert() does not take (nor store) the
   objects as "const" and the `lh_doall[_arg]` callback wrappers are not
   prototyped to have "const" restrictions on the object pointers they are
   given (and so aren't required to cast them away any more).

   *Geoff Thorpe*

 * The tmdiff.h API was so ugly and minimal that our own timing utility
   (speed) prefers to use its own implementation. The two implementations
   haven't been consolidated as yet (volunteers?) but the tmdiff API has had
   its object type properly exposed (MS_TM) instead of casting to/from
   `char *`. This may still change yet if someone realises MS_TM and
   `ms_time_***`
   aren't necessarily the greatest nomenclatures - but this is what was used
   internally to the implementation so I've used that for now.

   *Geoff Thorpe*

 * Ensure that deprecated functions do not get compiled when
   OPENSSL_NO_DEPRECATED is defined. Some "openssl" subcommands and a few of
   the self-tests were still using deprecated key-generation functions so
   these have been updated also.

   *Geoff Thorpe*

 * Reorganise PKCS#7 code to separate the digest location functionality
   into PKCS7_find_digest(), digest addition into PKCS7_bio_add_digest().
   New function PKCS7_set_digest() to set the digest type for PKCS#7
   digestedData type. Add additional code to correctly generate the
   digestedData type and add support for this type in PKCS7 initialization
   functions.

   *Steve Henson*

 * New function PKCS7_set0_type_other() this initializes a PKCS7
   structure of type "other".

   *Steve Henson*

 * Fix prime generation loop in crypto/bn/bn_prime.pl by making
   sure the loop does correctly stop and breaking ("division by zero")
   modulus operations are not performed. The (pre-generated) prime
   table crypto/bn/bn_prime.h was already correct, but it could not be
   re-generated on some platforms because of the "division by zero"
   situation in the script.

   *Ralf S. Engelschall*

 * Update support for ECC-based TLS ciphersuites according to
   draft-ietf-tls-ecc-03.txt: the KDF1 key derivation function with
   SHA-1 now is only used for "small" curves (where the
   representation of a field element takes up to 24 bytes); for
   larger curves, the field element resulting from ECDH is directly
   used as premaster secret.

   *Douglas Stebila (Sun Microsystems Laboratories)*

 * Add code for kP+lQ timings to crypto/ec/ectest.c, and add SEC2
   curve secp160r1 to the tests.

   *Douglas Stebila (Sun Microsystems Laboratories)*

 * Add the possibility to load symbols globally with DSO.

   *Götz Babin-Ebell <babin-ebell@trustcenter.de> via Richard Levitte*

 * Add the functions ERR_set_mark() and ERR_pop_to_mark() for better
   control of the error stack.

   *Richard Levitte*

 * Add support for STORE in ENGINE.

   *Richard Levitte*

 * Add the STORE type.  The intention is to provide a common interface
   to certificate and key stores, be they simple file-based stores, or
   HSM-type store, or LDAP stores, or...
   NOTE: The code is currently UNTESTED and isn't really used anywhere.

   *Richard Levitte*

 * Add a generic structure called OPENSSL_ITEM.  This can be used to
   pass a list of arguments to any function as well as provide a way
   for a function to pass data back to the caller.

   *Richard Levitte*

 * Add the functions BUF_strndup() and BUF_memdup().  BUF_strndup()
   works like BUF_strdup() but can be used to duplicate a portion of
   a string.  The copy gets NUL-terminated.  BUF_memdup() duplicates
   a memory area.

   *Richard Levitte*

 * Add the function sk_find_ex() which works like sk_find(), but will
   return an index to an element even if an exact match couldn't be
   found.  The index is guaranteed to point at the element where the
   searched-for key would be inserted to preserve sorting order.

   *Richard Levitte*

 * Add the function OBJ_bsearch_ex() which works like OBJ_bsearch() but
   takes an extra flags argument for optional functionality.  Currently,
   the following flags are defined:

      OBJ_BSEARCH_VALUE_ON_NOMATCH
      This one gets OBJ_bsearch_ex() to return a pointer to the first
      element where the comparing function returns a negative or zero
      number.

      OBJ_BSEARCH_FIRST_VALUE_ON_MATCH
      This one gets OBJ_bsearch_ex() to return a pointer to the first
      element where the comparing function returns zero.  This is useful
      if there are more than one element where the comparing function
      returns zero.

   *Richard Levitte*

 * Make it possible to create self-signed certificates with 'openssl ca'
   in such a way that the self-signed certificate becomes part of the
   CA database and uses the same mechanisms for serial number generation
   as all other certificate signing.  The new flag '-selfsign' enables
   this functionality.  Adapt CA.sh and CA.pl.in.

   *Richard Levitte*

 * Add functionality to check the public key of a certificate request
   against a given private.  This is useful to check that a certificate
   request can be signed by that key (self-signing).

   *Richard Levitte*

 * Make it possible to have multiple active certificates with the same
   subject in the CA index file.  This is done only if the keyword
   'unique_subject' is set to 'no' in the main CA section (default
   if 'CA_default') of the configuration file.  The value is saved
   with the database itself in a separate index attribute file,
   named like the index file with '.attr' appended to the name.

   *Richard Levitte*

 * Generate multi-valued AVAs using '+' notation in config files for
   req and dirName.

   *Steve Henson*

 * Support for nameConstraints certificate extension.

   *Steve Henson*

 * Support for policyConstraints certificate extension.

   *Steve Henson*

 * Support for policyMappings certificate extension.

   *Steve Henson*

 * Make sure the default DSA_METHOD implementation only uses its
   dsa_mod_exp() and/or bn_mod_exp() handlers if they are non-NULL,
   and change its own handlers to be NULL so as to remove unnecessary
   indirection. This lets alternative implementations fallback to the
   default implementation more easily.

   *Geoff Thorpe*

 * Support for directoryName in GeneralName related extensions
   in config files.

   *Steve Henson*

 * Make it possible to link applications using Makefile.shared.
   Make that possible even when linking against static libraries!

   *Richard Levitte*

 * Support for single pass processing for S/MIME signing. This now
   means that S/MIME signing can be done from a pipe, in addition
   cleartext signing (multipart/signed type) is effectively streaming
   and the signed data does not need to be all held in memory.

   This is done with a new flag PKCS7_STREAM. When this flag is set
   PKCS7_sign() only initializes the PKCS7 structure and the actual signing
   is done after the data is output (and digests calculated) in
   SMIME_write_PKCS7().

   *Steve Henson*

 * Add full support for -rpath/-R, both in shared libraries and
   applications, at least on the platforms where it's known how
   to do it.

   *Richard Levitte*

 * In crypto/ec/ec_mult.c, implement fast point multiplication with
   precomputation, based on wNAF splitting: EC_GROUP_precompute_mult()
   will now compute a table of multiples of the generator that
   makes subsequent invocations of EC_POINTs_mul() or EC_POINT_mul()
   faster (notably in the case of a single point multiplication,
   scalar * generator).

   *Nils Larsch, Bodo Moeller*

 * IPv6 support for certificate extensions. The various extensions
   which use the IP:a.b.c.d can now take IPv6 addresses using the
   formats of RFC1884 2.2 . IPv6 addresses are now also displayed
   correctly.

   *Steve Henson*

 * Added an ENGINE that implements RSA by performing private key
   exponentiations with the GMP library. The conversions to and from
   GMP's mpz_t format aren't optimised nor are any montgomery forms
   cached, and on x86 it appears OpenSSL's own performance has caught up.
   However there are likely to be other architectures where GMP could
   provide a boost. This ENGINE is not built in by default, but it can be
   specified at Configure time and should be accompanied by the necessary
   linker additions, eg;
           ./config -DOPENSSL_USE_GMP -lgmp

   *Geoff Thorpe*

 * "openssl engine" will not display ENGINE/DSO load failure errors when
   testing availability of engines with "-t" - the old behaviour is
   produced by increasing the feature's verbosity with "-tt".

   *Geoff Thorpe*

 * ECDSA routines: under certain error conditions uninitialized BN objects
   could be freed. Solution: make sure initialization is performed early
   enough. (Reported and fix supplied by Nils Larsch <nla@trustcenter.de>
   via PR#459)

   *Lutz Jaenicke*

 * Key-generation can now be implemented in RSA_METHOD, DSA_METHOD
   and DH_METHOD (eg. by ENGINE implementations) to override the normal
   software implementations. For DSA and DH, parameter generation can
   also be overridden by providing the appropriate method callbacks.

   *Geoff Thorpe*

 * Change the "progress" mechanism used in key-generation and
   primality testing to functions that take a new BN_GENCB pointer in
   place of callback/argument pairs. The new API functions have `_ex`
   postfixes and the older functions are reimplemented as wrappers for
   the new ones. The OPENSSL_NO_DEPRECATED symbol can be used to hide
   declarations of the old functions to help (graceful) attempts to
   migrate to the new functions. Also, the new key-generation API
   functions operate on a caller-supplied key-structure and return
   success/failure rather than returning a key or NULL - this is to
   help make "keygen" another member function of RSA_METHOD etc.

   Example for using the new callback interface:

           int (*my_callback)(int a, int b, BN_GENCB *cb) = ...;
           void *my_arg = ...;
           BN_GENCB my_cb;

           BN_GENCB_set(&my_cb, my_callback, my_arg);

           return BN_is_prime_ex(some_bignum, BN_prime_checks, NULL, &cb);
           /* For the meaning of a, b in calls to my_callback(), see the
            * documentation of the function that calls the callback.
            * cb will point to my_cb; my_arg can be retrieved as cb->arg.
            * my_callback should return 1 if it wants BN_is_prime_ex()
            * to continue, or 0 to stop.
            */

   *Geoff Thorpe*

 * Change the ZLIB compression method to be stateful, and make it
   available to TLS with the number defined in
   draft-ietf-tls-compression-04.txt.

   *Richard Levitte*

 * Add the ASN.1 structures and functions for CertificatePair, which
   is defined as follows (according to X.509_4thEditionDraftV6.pdf):

           CertificatePair ::= SEQUENCE {
              forward         [0]     Certificate OPTIONAL,
              reverse         [1]     Certificate OPTIONAL,
              -- at least one of the pair shall be present -- }

   Also implement the PEM functions to read and write certificate
   pairs, and defined the PEM tag as "CERTIFICATE PAIR".

   This needed to be defined, mostly for the sake of the LDAP
   attribute crossCertificatePair, but may prove useful elsewhere as
   well.

   *Richard Levitte*

 * Make it possible to inhibit symlinking of shared libraries in
   Makefile.shared, for Cygwin's sake.

   *Richard Levitte*

 * Extend the BIGNUM API by creating a function
           void BN_set_negative(BIGNUM *a, int neg);
   and a macro that behave like
           int  BN_is_negative(const BIGNUM *a);

   to avoid the need to access 'a->neg' directly in applications.

   *Nils Larsch*

 * Implement fast modular reduction for pseudo-Mersenne primes
   used in NIST curves (crypto/bn/bn_nist.c, crypto/ec/ecp_nist.c).
   EC_GROUP_new_curve_GFp() will now automatically use this
   if applicable.

   *Nils Larsch <nla@trustcenter.de>*

 * Add new lock type (CRYPTO_LOCK_BN).

   *Bodo Moeller*

 * Change the ENGINE framework to automatically load engines
   dynamically from specific directories unless they could be
   found to already be built in or loaded.  Move all the
   current engines except for the cryptodev one to a new
   directory engines/.
   The engines in engines/ are built as shared libraries if
   the "shared" options was given to ./Configure or ./config.
   Otherwise, they are inserted in libcrypto.a.
   /usr/local/ssl/engines is the default directory for dynamic
   engines, but that can be overridden at configure time through
   the usual use of --prefix and/or --openssldir, and at run
   time with the environment variable OPENSSL_ENGINES.

   *Geoff Thorpe and Richard Levitte*

 * Add Makefile.shared, a helper makefile to build shared
   libraries.  Adapt Makefile.org.

   *Richard Levitte*

 * Add version info to Win32 DLLs.

   *Peter 'Luna' Runestig" <peter@runestig.com>*

 * Add new 'medium level' PKCS#12 API. Certificates and keys
   can be added using this API to created arbitrary PKCS#12
   files while avoiding the low-level API.

   New options to PKCS12_create(), key or cert can be NULL and
   will then be omitted from the output file. The encryption
   algorithm NIDs can be set to -1 for no encryption, the mac
   iteration count can be set to 0 to omit the mac.

   Enhance pkcs12 utility by making the -nokeys and -nocerts
   options work when creating a PKCS#12 file. New option -nomac
   to omit the mac, NONE can be set for an encryption algorithm.
   New code is modified to use the enhanced PKCS12_create()
   instead of the low-level API.

   *Steve Henson*

 * Extend ASN1 encoder to support indefinite length constructed
   encoding. This can output sequences tags and octet strings in
   this form. Modify pk7_asn1.c to support indefinite length
   encoding. This is experimental and needs additional code to
   be useful, such as an ASN1 bio and some enhanced streaming
   PKCS#7 code.

   Extend template encode functionality so that tagging is passed
   down to the template encoder.

   *Steve Henson*

 * Let 'openssl req' fail if an argument to '-newkey' is not
   recognized instead of using RSA as a default.

   *Bodo Moeller*

 * Add support for ECC-based ciphersuites from draft-ietf-tls-ecc-01.txt.
   As these are not official, they are not included in "ALL";
   the "ECCdraft" ciphersuite group alias can be used to select them.

   *Vipul Gupta and Sumit Gupta (Sun Microsystems Laboratories)*

 * Add ECDH engine support.

   *Nils Gura and Douglas Stebila (Sun Microsystems Laboratories)*

 * Add ECDH in new directory crypto/ecdh/.

   *Douglas Stebila (Sun Microsystems Laboratories)*

 * Let BN_rand_range() abort with an error after 100 iterations
   without success (which indicates a broken PRNG).

   *Bodo Moeller*

 * Change BN_mod_sqrt() so that it verifies that the input value
   is really the square of the return value.  (Previously,
   BN_mod_sqrt would show GIGO behaviour.)

   *Bodo Moeller*

 * Add named elliptic curves over binary fields from X9.62, SECG,
   and WAP/WTLS; add OIDs that were still missing.

   *Sheueling Chang Shantz and Douglas Stebila (Sun Microsystems Laboratories)*

 * Extend the EC library for elliptic curves over binary fields
   (new files ec2_smpl.c, ec2_smpt.c, ec2_mult.c in crypto/ec/).
   New EC_METHOD:

           EC_GF2m_simple_method

   New API functions:

           EC_GROUP_new_curve_GF2m
           EC_GROUP_set_curve_GF2m
           EC_GROUP_get_curve_GF2m
           EC_POINT_set_affine_coordinates_GF2m
           EC_POINT_get_affine_coordinates_GF2m
           EC_POINT_set_compressed_coordinates_GF2m

   Point compression for binary fields is disabled by default for
   patent reasons (compile with OPENSSL_EC_BIN_PT_COMP defined to
   enable it).

   As binary polynomials are represented as BIGNUMs, various members
   of the EC_GROUP and EC_POINT data structures can be shared
   between the implementations for prime fields and binary fields;
   the above `..._GF2m functions` (except for EX_GROUP_new_curve_GF2m)
   are essentially identical to their `..._GFp` counterparts.
   (For simplicity, the `..._GFp` prefix has been dropped from
   various internal method names.)

   An internal 'field_div' method (similar to 'field_mul' and
   'field_sqr') has been added; this is used only for binary fields.

   *Sheueling Chang Shantz and Douglas Stebila (Sun Microsystems Laboratories)*

 * Optionally dispatch EC_POINT_mul(), EC_POINT_precompute_mult()
   through methods ('mul', 'precompute_mult').

   The generic implementations (now internally called 'ec_wNAF_mul'
   and 'ec_wNAF_precomputed_mult') remain the default if these
   methods are undefined.

   *Sheueling Chang Shantz and Douglas Stebila (Sun Microsystems Laboratories)*

 * New function EC_GROUP_get_degree, which is defined through
   EC_METHOD.  For curves over prime fields, this returns the bit
   length of the modulus.

   *Sheueling Chang Shantz and Douglas Stebila (Sun Microsystems Laboratories)*

 * New functions EC_GROUP_dup, EC_POINT_dup.
   (These simply call ..._new  and ..._copy).

   *Sheueling Chang Shantz and Douglas Stebila (Sun Microsystems Laboratories)*

 * Add binary polynomial arithmetic software in crypto/bn/bn_gf2m.c.
   Polynomials are represented as BIGNUMs (where the sign bit is not
   used) in the following functions [macros]:

           BN_GF2m_add
           BN_GF2m_sub             [= BN_GF2m_add]
           BN_GF2m_mod             [wrapper for BN_GF2m_mod_arr]
           BN_GF2m_mod_mul         [wrapper for BN_GF2m_mod_mul_arr]
           BN_GF2m_mod_sqr         [wrapper for BN_GF2m_mod_sqr_arr]
           BN_GF2m_mod_inv
           BN_GF2m_mod_exp         [wrapper for BN_GF2m_mod_exp_arr]
           BN_GF2m_mod_sqrt        [wrapper for BN_GF2m_mod_sqrt_arr]
           BN_GF2m_mod_solve_quad  [wrapper for BN_GF2m_mod_solve_quad_arr]
           BN_GF2m_cmp             [= BN_ucmp]

   (Note that only the 'mod' functions are actually for fields GF(2^m).
   BN_GF2m_add() is misnomer, but this is for the sake of consistency.)

   For some functions, an the irreducible polynomial defining a
   field can be given as an 'unsigned int[]' with strictly
   decreasing elements giving the indices of those bits that are set;
   i.e., p[] represents the polynomial
           f(t) = t^p[0] + t^p[1] + ... + t^p[k]
   where
           p[0] > p[1] > ... > p[k] = 0.
   This applies to the following functions:

           BN_GF2m_mod_arr
           BN_GF2m_mod_mul_arr
           BN_GF2m_mod_sqr_arr
           BN_GF2m_mod_inv_arr        [wrapper for BN_GF2m_mod_inv]
           BN_GF2m_mod_div_arr        [wrapper for BN_GF2m_mod_div]
           BN_GF2m_mod_exp_arr
           BN_GF2m_mod_sqrt_arr
           BN_GF2m_mod_solve_quad_arr
           BN_GF2m_poly2arr
           BN_GF2m_arr2poly

   Conversion can be performed by the following functions:

           BN_GF2m_poly2arr
           BN_GF2m_arr2poly

   bntest.c has additional tests for binary polynomial arithmetic.

   Two implementations for BN_GF2m_mod_div() are available.
   The default algorithm simply uses BN_GF2m_mod_inv() and
   BN_GF2m_mod_mul().  The alternative algorithm is compiled in only
   if OPENSSL_SUN_GF2M_DIV is defined (patent pending; read the
   copyright notice in crypto/bn/bn_gf2m.c before enabling it).

   *Sheueling Chang Shantz and Douglas Stebila (Sun Microsystems Laboratories)*

 * Add new error code 'ERR_R_DISABLED' that can be used when some
   functionality is disabled at compile-time.

   *Douglas Stebila <douglas.stebila@sun.com>*

 * Change default behaviour of 'openssl asn1parse' so that more
   information is visible when viewing, e.g., a certificate:

   Modify asn1_parse2 (crypto/asn1/asn1_par.c) so that in non-'dump'
   mode the content of non-printable OCTET STRINGs is output in a
   style similar to INTEGERs, but with '[HEX DUMP]' prepended to
   avoid the appearance of a printable string.

   *Nils Larsch <nla@trustcenter.de>*

 * Add 'asn1_flag' and 'asn1_form' member to EC_GROUP with access
   functions
           EC_GROUP_set_asn1_flag()
           EC_GROUP_get_asn1_flag()
           EC_GROUP_set_point_conversion_form()
           EC_GROUP_get_point_conversion_form()
   These control ASN1 encoding details:
   - Curves (i.e., groups) are encoded explicitly unless asn1_flag
     has been set to OPENSSL_EC_NAMED_CURVE.
   - Points are encoded in uncompressed form by default; options for
     asn1_for are as for point2oct, namely
           POINT_CONVERSION_COMPRESSED
           POINT_CONVERSION_UNCOMPRESSED
           POINT_CONVERSION_HYBRID

   Also add 'seed' and 'seed_len' members to EC_GROUP with access
   functions
           EC_GROUP_set_seed()
           EC_GROUP_get0_seed()
           EC_GROUP_get_seed_len()
   This is used only for ASN1 purposes (so far).

   *Nils Larsch <nla@trustcenter.de>*

 * Add 'field_type' member to EC_METHOD, which holds the NID
   of the appropriate field type OID.  The new function
   EC_METHOD_get_field_type() returns this value.

   *Nils Larsch <nla@trustcenter.de>*

 * Add functions
           EC_POINT_point2bn()
           EC_POINT_bn2point()
           EC_POINT_point2hex()
           EC_POINT_hex2point()
   providing useful interfaces to EC_POINT_point2oct() and
   EC_POINT_oct2point().

   *Nils Larsch <nla@trustcenter.de>*

 * Change internals of the EC library so that the functions
           EC_GROUP_set_generator()
           EC_GROUP_get_generator()
           EC_GROUP_get_order()
           EC_GROUP_get_cofactor()
   are implemented directly in crypto/ec/ec_lib.c and not dispatched
   to methods, which would lead to unnecessary code duplication when
   adding different types of curves.

   *Nils Larsch <nla@trustcenter.de> with input by Bodo Moeller*

 * Implement compute_wNAF (crypto/ec/ec_mult.c) without BIGNUM
   arithmetic, and such that modified wNAFs are generated
   (which avoid length expansion in many cases).

   *Bodo Moeller*

 * Add a function EC_GROUP_check_discriminant() (defined via
   EC_METHOD) that verifies that the curve discriminant is non-zero.

   Add a function EC_GROUP_check() that makes some sanity tests
   on a EC_GROUP, its generator and order.  This includes
   EC_GROUP_check_discriminant().

   *Nils Larsch <nla@trustcenter.de>*

 * Add ECDSA in new directory crypto/ecdsa/.

   Add applications 'openssl ecparam' and 'openssl ecdsa'
   (these are based on 'openssl dsaparam' and 'openssl dsa').

   ECDSA support is also included in various other files across the
   library.  Most notably,
   - 'openssl req' now has a '-newkey ecdsa:file' option;
   - EVP_PKCS82PKEY (crypto/evp/evp_pkey.c) now can handle ECDSA;
   - X509_PUBKEY_get (crypto/asn1/x_pubkey.c) and
     d2i_PublicKey (crypto/asn1/d2i_pu.c) have been modified to make
     them suitable for ECDSA where domain parameters must be
     extracted before the specific public key;
   - ECDSA engine support has been added.

   *Nils Larsch <nla@trustcenter.de>*

 * Include some named elliptic curves, and add OIDs from X9.62,
   SECG, and WAP/WTLS.  Each curve can be obtained from the new
   function
           EC_GROUP_new_by_curve_name(),
   and the list of available named curves can be obtained with
           EC_get_builtin_curves().
   Also add a 'curve_name' member to EC_GROUP objects, which can be
   accessed via
           EC_GROUP_set_curve_name()
           EC_GROUP_get_curve_name()

   *Nils Larsch <larsch@trustcenter.de, Bodo Moeller*

 * Remove a few calls to bn_wexpand() in BN_sqr() (the one in there
   was actually never needed) and in BN_mul().  The removal in BN_mul()
   required a small change in bn_mul_part_recursive() and the addition
   of the functions bn_cmp_part_words(), bn_sub_part_words() and
   bn_add_part_words(), which do the same thing as bn_cmp_words(),
   bn_sub_words() and bn_add_words() except they take arrays with
   differing sizes.

   *Richard Levitte*

### Changes between 0.9.7l and 0.9.7m  [23 Feb 2007]

 * Cleanse PEM buffers before freeing them since they may contain
   sensitive data.

   *Benjamin Bennett <ben@psc.edu>*

 * Include "!eNULL" in SSL_DEFAULT_CIPHER_LIST to make sure that
   a ciphersuite string such as "DEFAULT:RSA" cannot enable
   authentication-only ciphersuites.

   *Bodo Moeller*

 * Since AES128 and AES256 share a single mask bit in the logic of
   ssl/ssl_ciph.c, the code for masking out disabled ciphers needs a
   kludge to work properly if AES128 is available and AES256 isn't.

   *Victor Duchovni*

 * Expand security boundary to match 1.1.1 module.

   *Steve Henson*

 * Remove redundant features: hash file source, editing of test vectors
   modify fipsld to use external fips_premain.c signature.

   *Steve Henson*

 * New perl script mkfipsscr.pl to create shell scripts or batch files to
   run algorithm test programs.

   *Steve Henson*

 * Make algorithm test programs more tolerant of whitespace.

   *Steve Henson*

 * Have SSL/TLS server implementation tolerate "mismatched" record
   protocol version while receiving ClientHello even if the
   ClientHello is fragmented.  (The server can't insist on the
   particular protocol version it has chosen before the ServerHello
   message has informed the client about his choice.)

   *Bodo Moeller*

 * Load error codes if they are not already present instead of using a
   static variable. This allows them to be cleanly unloaded and reloaded.

   *Steve Henson*

### Changes between 0.9.7k and 0.9.7l  [28 Sep 2006]

 * Introduce limits to prevent malicious keys being able to
   cause a denial of service.  ([CVE-2006-2940])

   *Steve Henson, Bodo Moeller*

 * Fix ASN.1 parsing of certain invalid structures that can result
   in a denial of service.  ([CVE-2006-2937])  [Steve Henson]

 * Fix buffer overflow in SSL_get_shared_ciphers() function.
   ([CVE-2006-3738]) [Tavis Ormandy and Will Drewry, Google Security Team]

 * Fix SSL client code which could crash if connecting to a
   malicious SSLv2 server.  ([CVE-2006-4343])

   *Tavis Ormandy and Will Drewry, Google Security Team*

 * Change ciphersuite string processing so that an explicit
   ciphersuite selects this one ciphersuite (so that "AES256-SHA"
   will no longer include "AES128-SHA"), and any other similar
   ciphersuite (same bitmap) from *other* protocol versions (so that
   "RC4-MD5" will still include both the SSL 2.0 ciphersuite and the
   SSL 3.0/TLS 1.0 ciphersuite).  This is a backport combining
   changes from 0.9.8b and 0.9.8d.

   *Bodo Moeller*

### Changes between 0.9.7j and 0.9.7k  [05 Sep 2006]

 * Avoid PKCS #1 v1.5 signature attack discovered by Daniel Bleichenbacher
   ([CVE-2006-4339])  [Ben Laurie and Google Security Team]

 * Change the Unix randomness entropy gathering to use poll() when
   possible instead of select(), since the latter has some
   undesirable limitations.

   *Darryl Miles via Richard Levitte and Bodo Moeller*

 * Disable rogue ciphersuites:

   - SSLv2 0x08 0x00 0x80 ("RC4-64-MD5")
   - SSLv3/TLSv1 0x00 0x61 ("EXP1024-RC2-CBC-MD5")
   - SSLv3/TLSv1 0x00 0x60 ("EXP1024-RC4-MD5")

   The latter two were purportedly from
   draft-ietf-tls-56-bit-ciphersuites-0[01].txt, but do not really
   appear there.

   Also deactivate the remaining ciphersuites from
   draft-ietf-tls-56-bit-ciphersuites-01.txt.  These are just as
   unofficial, and the ID has long expired.

   *Bodo Moeller*

 * Fix RSA blinding Heisenbug (problems sometimes occurred on
   dual-core machines) and other potential thread-safety issues.

   *Bodo Moeller*

### Changes between 0.9.7i and 0.9.7j  [04 May 2006]

 * Adapt fipsld and the build system to link against the validated FIPS
   module in FIPS mode.

   *Steve Henson*

 * Fixes for VC++ 2005 build under Windows.

   *Steve Henson*

 * Add new Windows build target VC-32-GMAKE for VC++. This uses GNU make
   from a Windows bash shell such as MSYS. It is autodetected from the
   "config" script when run from a VC++ environment. Modify standard VC++
   build to use fipscanister.o from the GNU make build.

   *Steve Henson*

### Changes between 0.9.7h and 0.9.7i  [14 Oct 2005]

 * Wrapped the definition of EVP_MAX_MD_SIZE in a #ifdef OPENSSL_FIPS.
   The value now differs depending on if you build for FIPS or not.
   BEWARE!  A program linked with a shared FIPSed libcrypto can't be
   safely run with a non-FIPSed libcrypto, as it may crash because of
   the difference induced by this change.

   *Andy Polyakov*

### Changes between 0.9.7g and 0.9.7h  [11 Oct 2005]

 * Remove the functionality of SSL_OP_MSIE_SSLV2_RSA_PADDING
   (part of SSL_OP_ALL).  This option used to disable the
   countermeasure against man-in-the-middle protocol-version
   rollback in the SSL 2.0 server implementation, which is a bad
   idea.  ([CVE-2005-2969])

   *Bodo Moeller; problem pointed out by Yutaka Oiwa (Research Center
   for Information Security, National Institute of Advanced Industrial
   Science and Technology [AIST, Japan)]*

 * Minimal support for X9.31 signatures and PSS padding modes. This is
   mainly for FIPS compliance and not fully integrated at this stage.

   *Steve Henson*

 * For DSA signing, unless DSA_FLAG_NO_EXP_CONSTTIME is set, perform
   the exponentiation using a fixed-length exponent.  (Otherwise,
   the information leaked through timing could expose the secret key
   after many signatures; cf. Bleichenbacher's attack on DSA with
   biased k.)

   *Bodo Moeller*

 * Make a new fixed-window mod_exp implementation the default for
   RSA, DSA, and DH private-key operations so that the sequence of
   squares and multiplies and the memory access pattern are
   independent of the particular secret key.  This will mitigate
   cache-timing and potential related attacks.

   BN_mod_exp_mont_consttime() is the new exponentiation implementation,
   and this is automatically used by BN_mod_exp_mont() if the new flag
   BN_FLG_EXP_CONSTTIME is set for the exponent.  RSA, DSA, and DH
   will use this BN flag for private exponents unless the flag
   RSA_FLAG_NO_EXP_CONSTTIME, DSA_FLAG_NO_EXP_CONSTTIME, or
   DH_FLAG_NO_EXP_CONSTTIME, respectively, is set.

   *Matthew D Wood (Intel Corp), with some changes by Bodo Moeller*

 * Change the client implementation for SSLv23_method() and
   SSLv23_client_method() so that is uses the SSL 3.0/TLS 1.0
   Client Hello message format if the SSL_OP_NO_SSLv2 option is set.
   (Previously, the SSL 2.0 backwards compatible Client Hello
   message format would be used even with SSL_OP_NO_SSLv2.)

   *Bodo Moeller*

 * Add support for smime-type MIME parameter in S/MIME messages which some
   clients need.

   *Steve Henson*

 * New function BN_MONT_CTX_set_locked() to set montgomery parameters in
   a threadsafe manner. Modify rsa code to use new function and add calls
   to dsa and dh code (which had race conditions before).

   *Steve Henson*

 * Include the fixed error library code in the C error file definitions
   instead of fixing them up at runtime. This keeps the error code
   structures constant.

   *Steve Henson*

### Changes between 0.9.7f and 0.9.7g  [11 Apr 2005]

[NB: OpenSSL 0.9.7h and later 0.9.7 patch levels were released after
OpenSSL 0.9.8.]

 * Fixes for newer kerberos headers. NB: the casts are needed because
   the 'length' field is signed on one version and unsigned on another
   with no (?) obvious way to tell the difference, without these VC++
   complains. Also the "definition" of FAR (blank) is no longer included
   nor is the error ENOMEM. KRB5_PRIVATE has to be set to 1 to pick up
   some needed definitions.

   *Steve Henson*

 * Undo Cygwin change.

   *Ulf Möller*

 * Added support for proxy certificates according to RFC 3820.
   Because they may be a security thread to unaware applications,
   they must be explicitly allowed in run-time.  See
   docs/HOWTO/proxy_certificates.txt for further information.

   *Richard Levitte*

### Changes between 0.9.7e and 0.9.7f  [22 Mar 2005]

 * Use (SSL_RANDOM_VALUE - 4) bytes of pseudo random data when generating
   server and client random values. Previously
   (SSL_RANDOM_VALUE - sizeof(time_t)) would be used which would result in
   less random data when sizeof(time_t) > 4 (some 64 bit platforms).

   This change has negligible security impact because:

   1. Server and client random values still have 24 bytes of pseudo random
      data.

   2. Server and client random values are sent in the clear in the initial
      handshake.

   3. The master secret is derived using the premaster secret (48 bytes in
      size for static RSA ciphersuites) as well as client server and random
      values.

   The OpenSSL team would like to thank the UK NISCC for bringing this issue
   to our attention.

   *Stephen Henson, reported by UK NISCC*

 * Use Windows randomness collection on Cygwin.

   *Ulf Möller*

 * Fix hang in EGD/PRNGD query when communication socket is closed
   prematurely by EGD/PRNGD.

   *Darren Tucker <dtucker@zip.com.au> via Lutz Jänicke, resolves #1014*

 * Prompt for pass phrases when appropriate for PKCS12 input format.

   *Steve Henson*

 * Back-port of selected performance improvements from development
   branch, as well as improved support for PowerPC platforms.

   *Andy Polyakov*

 * Add lots of checks for memory allocation failure, error codes to indicate
   failure and freeing up memory if a failure occurs.

   *Nauticus Networks SSL Team <openssl@nauticusnet.com>, Steve Henson*

 * Add new -passin argument to dgst.

   *Steve Henson*

 * Perform some character comparisons of different types in X509_NAME_cmp:
   this is needed for some certificates that re-encode DNs into UTF8Strings
   (in violation of RFC3280) and can't or won't issue name rollover
   certificates.

   *Steve Henson*

 * Make an explicit check during certificate validation to see that
   the CA setting in each certificate on the chain is correct.  As a
   side effect always do the following basic checks on extensions,
   not just when there's an associated purpose to the check:

   - if there is an unhandled critical extension (unless the user
     has chosen to ignore this fault)
   - if the path length has been exceeded (if one is set at all)
   - that certain extensions fit the associated purpose (if one has
     been given)

   *Richard Levitte*

### Changes between 0.9.7d and 0.9.7e  [25 Oct 2004]

 * Avoid a race condition when CRLs are checked in a multi threaded
   environment. This would happen due to the reordering of the revoked
   entries during signature checking and serial number lookup. Now the
   encoding is cached and the serial number sort performed under a lock.
   Add new STACK function sk_is_sorted().

   *Steve Henson*

 * Add Delta CRL to the extension code.

   *Steve Henson*

 * Various fixes to s3_pkt.c so alerts are sent properly.

   *David Holmes <d.holmes@f5.com>*

 * Reduce the chances of duplicate issuer name and serial numbers (in
   violation of RFC3280) using the OpenSSL certificate creation utilities.
   This is done by creating a random 64 bit value for the initial serial
   number when a serial number file is created or when a self signed
   certificate is created using 'openssl req -x509'. The initial serial
   number file is created using 'openssl x509 -next_serial' in CA.pl
   rather than being initialized to 1.

   *Steve Henson*

### Changes between 0.9.7c and 0.9.7d  [17 Mar 2004]

 * Fix null-pointer assignment in do_change_cipher_spec() revealed
   by using the Codenomicon TLS Test Tool ([CVE-2004-0079])

   *Joe Orton, Steve Henson*

 * Fix flaw in SSL/TLS handshaking when using Kerberos ciphersuites
   ([CVE-2004-0112])

   *Joe Orton, Steve Henson*

 * Make it possible to have multiple active certificates with the same
   subject in the CA index file.  This is done only if the keyword
   'unique_subject' is set to 'no' in the main CA section (default
   if 'CA_default') of the configuration file.  The value is saved
   with the database itself in a separate index attribute file,
   named like the index file with '.attr' appended to the name.

   *Richard Levitte*

 * X509 verify fixes. Disable broken certificate workarounds when
   X509_V_FLAGS_X509_STRICT is set. Check CRL issuer has cRLSign set if
   keyUsage extension present. Don't accept CRLs with unhandled critical
   extensions: since verify currently doesn't process CRL extensions this
   rejects a CRL with *any* critical extensions. Add new verify error codes
   for these cases.

   *Steve Henson*

 * When creating an OCSP nonce use an OCTET STRING inside the extnValue.
   A clarification of RFC2560 will require the use of OCTET STRINGs and
   some implementations cannot handle the current raw format. Since OpenSSL
   copies and compares OCSP nonces as opaque blobs without any attempt at
   parsing them this should not create any compatibility issues.

   *Steve Henson*

 * New md flag EVP_MD_CTX_FLAG_REUSE this allows md_data to be reused when
   calling EVP_MD_CTX_copy_ex() to avoid calling OPENSSL_malloc(). Without
   this HMAC (and other) operations are several times slower than OpenSSL
   < 0.9.7.

   *Steve Henson*

 * Print out GeneralizedTime and UTCTime in ASN1_STRING_print_ex().

   *Peter Sylvester <Peter.Sylvester@EdelWeb.fr>*

 * Use the correct content when signing type "other".

   *Steve Henson*

### Changes between 0.9.7b and 0.9.7c  [30 Sep 2003]

 * Fix various bugs revealed by running the NISCC test suite:

   Stop out of bounds reads in the ASN1 code when presented with
   invalid tags (CVE-2003-0543 and CVE-2003-0544).

   Free up ASN1_TYPE correctly if ANY type is invalid ([CVE-2003-0545]).

   If verify callback ignores invalid public key errors don't try to check
   certificate signature with the NULL public key.

   *Steve Henson*

 * New -ignore_err option in ocsp application to stop the server
   exiting on the first error in a request.

   *Steve Henson*

 * In ssl3_accept() (ssl/s3_srvr.c) only accept a client certificate
   if the server requested one: as stated in TLS 1.0 and SSL 3.0
   specifications.

   *Steve Henson*

 * In ssl3_get_client_hello() (ssl/s3_srvr.c), tolerate additional
   extra data after the compression methods not only for TLS 1.0
   but also for SSL 3.0 (as required by the specification).

   *Bodo Moeller; problem pointed out by Matthias Loepfe*

 * Change X509_certificate_type() to mark the key as exported/exportable
   when it's 512 *bits* long, not 512 bytes.

   *Richard Levitte*

 * Change AES_cbc_encrypt() so it outputs exact multiple of
   blocks during encryption.

   *Richard Levitte*

 * Various fixes to base64 BIO and non blocking I/O. On write
   flushes were not handled properly if the BIO retried. On read
   data was not being buffered properly and had various logic bugs.
   This also affects blocking I/O when the data being decoded is a
   certain size.

   *Steve Henson*

 * Various S/MIME bugfixes and compatibility changes:
   output correct application/pkcs7 MIME type if
   PKCS7_NOOLDMIMETYPE is set. Tolerate some broken signatures.
   Output CR+LF for EOL if PKCS7_CRLFEOL is set (this makes opening
   of files as .eml work). Correctly handle very long lines in MIME
   parser.

   *Steve Henson*

### Changes between 0.9.7a and 0.9.7b  [10 Apr 2003]

 * Countermeasure against the Klima-Pokorny-Rosa extension of
   Bleichbacher's attack on PKCS #1 v1.5 padding: treat
   a protocol version number mismatch like a decryption error
   in ssl3_get_client_key_exchange (ssl/s3_srvr.c).

   *Bodo Moeller*

 * Turn on RSA blinding by default in the default implementation
   to avoid a timing attack. Applications that don't want it can call
   RSA_blinding_off() or use the new flag RSA_FLAG_NO_BLINDING.
   They would be ill-advised to do so in most cases.

   *Ben Laurie, Steve Henson, Geoff Thorpe, Bodo Moeller*

 * Change RSA blinding code so that it works when the PRNG is not
   seeded (in this case, the secret RSA exponent is abused as
   an unpredictable seed -- if it is not unpredictable, there
   is no point in blinding anyway).  Make RSA blinding thread-safe
   by remembering the creator's thread ID in rsa->blinding and
   having all other threads use local one-time blinding factors
   (this requires more computation than sharing rsa->blinding, but
   avoids excessive locking; and if an RSA object is not shared
   between threads, blinding will still be very fast).

   *Bodo Moeller*

 * Fixed a typo bug that would cause ENGINE_set_default() to set an
   ENGINE as defaults for all supported algorithms irrespective of
   the 'flags' parameter. 'flags' is now honoured, so applications
   should make sure they are passing it correctly.

   *Geoff Thorpe*

 * Target "mingw" now allows native Windows code to be generated in
   the Cygwin environment as well as with the MinGW compiler.

   *Ulf Moeller*

### Changes between 0.9.7 and 0.9.7a  [19 Feb 2003]

 * In ssl3_get_record (ssl/s3_pkt.c), minimize information leaked
   via timing by performing a MAC computation even if incorrect
   block cipher padding has been found.  This is a countermeasure
   against active attacks where the attacker has to distinguish
   between bad padding and a MAC verification error. ([CVE-2003-0078])

   *Bodo Moeller; problem pointed out by Brice Canvel (EPFL),
   Alain Hiltgen (UBS), Serge Vaudenay (EPFL), and
   Martin Vuagnoux (EPFL, Ilion)*

 * Make the no-err option work as intended.  The intention with no-err
   is not to have the whole error stack handling routines removed from
   libcrypto, it's only intended to remove all the function name and
   reason texts, thereby removing some of the footprint that may not
   be interesting if those errors aren't displayed anyway.

   NOTE: it's still possible for any application or module to have its
   own set of error texts inserted.  The routines are there, just not
   used by default when no-err is given.

   *Richard Levitte*

 * Add support for FreeBSD on IA64.

   *dirk.meyer@dinoex.sub.org via Richard Levitte, resolves #454*

 * Adjust DES_cbc_cksum() so it returns the same value as the MIT
   Kerberos function mit_des_cbc_cksum().  Before this change,
   the value returned by DES_cbc_cksum() was like the one from
   mit_des_cbc_cksum(), except the bytes were swapped.

   *Kevin Greaney <Kevin.Greaney@hp.com> and Richard Levitte*

 * Allow an application to disable the automatic SSL chain building.
   Before this a rather primitive chain build was always performed in
   ssl3_output_cert_chain(): an application had no way to send the
   correct chain if the automatic operation produced an incorrect result.

   Now the chain builder is disabled if either:

   1. Extra certificates are added via SSL_CTX_add_extra_chain_cert().

   2. The mode flag SSL_MODE_NO_AUTO_CHAIN is set.

   The reasoning behind this is that an application would not want the
   auto chain building to take place if extra chain certificates are
   present and it might also want a means of sending no additional
   certificates (for example the chain has two certificates and the
   root is omitted).

   *Steve Henson*

 * Add the possibility to build without the ENGINE framework.

   *Steven Reddie <smr@essemer.com.au> via Richard Levitte*

 * Under Win32 gmtime() can return NULL: check return value in
   OPENSSL_gmtime(). Add error code for case where gmtime() fails.

   *Steve Henson*

 * DSA routines: under certain error conditions uninitialized BN objects
   could be freed. Solution: make sure initialization is performed early
   enough. (Reported and fix supplied by Ivan D Nestlerode <nestler@MIT.EDU>,
   Nils Larsch <nla@trustcenter.de> via PR#459)

   *Lutz Jaenicke*

 * Another fix for SSLv2 session ID handling: the session ID was incorrectly
   checked on reconnect on the client side, therefore session resumption
   could still fail with a "ssl session id is different" error. This
   behaviour is masked when SSL_OP_ALL is used due to
   SSL_OP_MICROSOFT_SESS_ID_BUG being set.
   Behaviour observed by Crispin Flowerday <crispin@flowerday.cx> as
   followup to PR #377.

   *Lutz Jaenicke*

 * IA-32 assembler support enhancements: unified ELF targets, support
   for SCO/Caldera platforms, fix for Cygwin shared build.

   *Andy Polyakov*

 * Add support for FreeBSD on sparc64.  As a consequence, support for
   FreeBSD on non-x86 processors is separate from x86 processors on
   the config script, much like the NetBSD support.

   *Richard Levitte & Kris Kennaway <kris@obsecurity.org>*

### Changes between 0.9.6h and 0.9.7  [31 Dec 2002]

[NB: OpenSSL 0.9.6i and later 0.9.6 patch levels were released after
OpenSSL 0.9.7.]

 * Fix session ID handling in SSLv2 client code: the SERVER FINISHED
   code (06) was taken as the first octet of the session ID and the last
   octet was ignored consequently. As a result SSLv2 client side session
   caching could not have worked due to the session ID mismatch between
   client and server.
   Behaviour observed by Crispin Flowerday <crispin@flowerday.cx> as
   PR #377.

   *Lutz Jaenicke*

 * Change the declaration of needed Kerberos libraries to use EX_LIBS
   instead of the special (and badly supported) LIBKRB5.  LIBKRB5 is
   removed entirely.

   *Richard Levitte*

 * The hw_ncipher.c engine requires dynamic locks.  Unfortunately, it
   seems that in spite of existing for more than a year, many application
   author have done nothing to provide the necessary callbacks, which
   means that this particular engine will not work properly anywhere.
   This is a very unfortunate situation which forces us, in the name
   of usability, to give the hw_ncipher.c a static lock, which is part
   of libcrypto.
   NOTE: This is for the 0.9.7 series ONLY.  This hack will never
   appear in 0.9.8 or later.  We EXPECT application authors to have
   dealt properly with this when 0.9.8 is released (unless we actually
   make such changes in the libcrypto locking code that changes will
   have to be made anyway).

   *Richard Levitte*

 * In asn1_d2i_read_bio() repeatedly call BIO_read() until all content
   octets have been read, EOF or an error occurs. Without this change
   some truncated ASN1 structures will not produce an error.

   *Steve Henson*

 * Disable Heimdal support, since it hasn't been fully implemented.
   Still give the possibility to force the use of Heimdal, but with
   warnings and a request that patches get sent to openssl-dev.

   *Richard Levitte*

 * Add the VC-CE target, introduce the WINCE sysname, and add
   INSTALL.WCE and appropriate conditionals to make it build.

   *Steven Reddie <smr@essemer.com.au> via Richard Levitte*

 * Change the DLL names for Cygwin to cygcrypto-x.y.z.dll and
   cygssl-x.y.z.dll, where x, y and z are the major, minor and
   edit numbers of the version.

   *Corinna Vinschen <vinschen@redhat.com> and Richard Levitte*

 * Introduce safe string copy and catenation functions
   (BUF_strlcpy() and BUF_strlcat()).

   *Ben Laurie (CHATS) and Richard Levitte*

 * Avoid using fixed-size buffers for one-line DNs.

   *Ben Laurie (CHATS)*

 * Add BUF_MEM_grow_clean() to avoid information leakage when
   resizing buffers containing secrets, and use where appropriate.

   *Ben Laurie (CHATS)*

 * Avoid using fixed size buffers for configuration file location.

   *Ben Laurie (CHATS)*

 * Avoid filename truncation for various CA files.

   *Ben Laurie (CHATS)*

 * Use sizeof in preference to magic numbers.

   *Ben Laurie (CHATS)*

 * Avoid filename truncation in cert requests.

   *Ben Laurie (CHATS)*

 * Add assertions to check for (supposedly impossible) buffer
   overflows.

   *Ben Laurie (CHATS)*

 * Don't cache truncated DNS entries in the local cache (this could
   potentially lead to a spoofing attack).

   *Ben Laurie (CHATS)*

 * Fix various buffers to be large enough for hex/decimal
   representations in a platform independent manner.

   *Ben Laurie (CHATS)*

 * Add CRYPTO_realloc_clean() to avoid information leakage when
   resizing buffers containing secrets, and use where appropriate.

   *Ben Laurie (CHATS)*

 * Add BIO_indent() to avoid much slightly worrying code to do
   indents.

   *Ben Laurie (CHATS)*

 * Convert sprintf()/BIO_puts() to BIO_printf().

   *Ben Laurie (CHATS)*

 * buffer_gets() could terminate with the buffer only half
   full. Fixed.

   *Ben Laurie (CHATS)*

 * Add assertions to prevent user-supplied crypto functions from
   overflowing internal buffers by having large block sizes, etc.

   *Ben Laurie (CHATS)*

 * New OPENSSL_assert() macro (similar to assert(), but enabled
   unconditionally).

   *Ben Laurie (CHATS)*

 * Eliminate unused copy of key in RC4.

   *Ben Laurie (CHATS)*

 * Eliminate unused and incorrectly sized buffers for IV in pem.h.

   *Ben Laurie (CHATS)*

 * Fix off-by-one error in EGD path.

   *Ben Laurie (CHATS)*

 * If RANDFILE path is too long, ignore instead of truncating.

   *Ben Laurie (CHATS)*

 * Eliminate unused and incorrectly sized X.509 structure
   CBCParameter.

   *Ben Laurie (CHATS)*

 * Eliminate unused and dangerous function knumber().

   *Ben Laurie (CHATS)*

 * Eliminate unused and dangerous structure, KSSL_ERR.

   *Ben Laurie (CHATS)*

 * Protect against overlong session ID context length in an encoded
   session object. Since these are local, this does not appear to be
   exploitable.

   *Ben Laurie (CHATS)*

 * Change from security patch (see 0.9.6e below) that did not affect
   the 0.9.6 release series:

   Remote buffer overflow in SSL3 protocol - an attacker could
   supply an oversized master key in Kerberos-enabled versions.
   ([CVE-2002-0657])

   *Ben Laurie (CHATS)*

 * Change the SSL kerb5 codes to match RFC 2712.

   *Richard Levitte*

 * Make -nameopt work fully for req and add -reqopt switch.

   *Michael Bell <michael.bell@rz.hu-berlin.de>, Steve Henson*

 * The "block size" for block ciphers in CFB and OFB mode should be 1.

   *Steve Henson, reported by Yngve Nysaeter Pettersen <yngve@opera.com>*

 * Make sure tests can be performed even if the corresponding algorithms
   have been removed entirely.  This was also the last step to make
   OpenSSL compilable with DJGPP under all reasonable conditions.

   *Richard Levitte, Doug Kaufman <dkaufman@rahul.net>*

 * Add cipher selection rules COMPLEMENTOFALL and COMPLEMENTOFDEFAULT
   to allow version independent disabling of normally unselected ciphers,
   which may be activated as a side-effect of selecting a single cipher.

   (E.g., cipher list string "RSA" enables ciphersuites that are left
   out of "ALL" because they do not provide symmetric encryption.
   "RSA:!COMPLEMEMENTOFALL" avoids these unsafe ciphersuites.)

   *Lutz Jaenicke, Bodo Moeller*

 * Add appropriate support for separate platform-dependent build
   directories.  The recommended way to make a platform-dependent
   build directory is the following (tested on Linux), maybe with
   some local tweaks:

           # Place yourself outside of the OpenSSL source tree.  In
           # this example, the environment variable OPENSSL_SOURCE
           # is assumed to contain the absolute OpenSSL source directory.
           mkdir -p objtree/"`uname -s`-`uname -r`-`uname -m`"
           cd objtree/"`uname -s`-`uname -r`-`uname -m`"
           (cd $OPENSSL_SOURCE; find . -type f) | while read F; do
                   mkdir -p `dirname $F`
                   ln -s $OPENSSL_SOURCE/$F $F
           done

   To be absolutely sure not to disturb the source tree, a "make clean"
   is a good thing.  If it isn't successful, don't worry about it,
   it probably means the source directory is very clean.

   *Richard Levitte*

 * Make sure any ENGINE control commands make local copies of string
   pointers passed to them whenever necessary. Otherwise it is possible
   the caller may have overwritten (or deallocated) the original string
   data when a later ENGINE operation tries to use the stored values.

   *Götz Babin-Ebell <babinebell@trustcenter.de>*

 * Improve diagnostics in file reading and command-line digests.

   *Ben Laurie aided and abetted by Solar Designer <solar@openwall.com>*

 * Add AES modes CFB and OFB to the object database.  Correct an
   error in AES-CFB decryption.

   *Richard Levitte*

 * Remove most calls to EVP_CIPHER_CTX_cleanup() in evp_enc.c, this
   allows existing EVP_CIPHER_CTX structures to be reused after
   calling `EVP_*Final()`. This behaviour is used by encryption
   BIOs and some applications. This has the side effect that
   applications must explicitly clean up cipher contexts with
   EVP_CIPHER_CTX_cleanup() or they will leak memory.

   *Steve Henson*

 * Check the values of dna and dnb in bn_mul_recursive before calling
   bn_mul_comba (a non zero value means the a or b arrays do not contain
   n2 elements) and fallback to bn_mul_normal if either is not zero.

   *Steve Henson*

 * Fix escaping of non-ASCII characters when using the -subj option
   of the "openssl req" command line tool. (Robert Joop <joop@fokus.gmd.de>)

   *Lutz Jaenicke*

 * Make object definitions compliant to LDAP (RFC2256): SN is the short
   form for "surname", serialNumber has no short form.
   Use "mail" as the short name for "rfc822Mailbox" according to RFC2798;
   therefore remove "mail" short name for "internet 7".
   The OID for unique identifiers in X509 certificates is
   x500UniqueIdentifier, not uniqueIdentifier.
   Some more OID additions. (Michael Bell <michael.bell@rz.hu-berlin.de>)

   *Lutz Jaenicke*

 * Add an "init" command to the ENGINE config module and auto initialize
   ENGINEs. Without any "init" command the ENGINE will be initialized
   after all ctrl commands have been executed on it. If init=1 the
   ENGINE is initialized at that point (ctrls before that point are run
   on the uninitialized ENGINE and after on the initialized one). If
   init=0 then the ENGINE will not be initialized at all.

   *Steve Henson*

 * Fix the 'app_verify_callback' interface so that the user-defined
   argument is actually passed to the callback: In the
   SSL_CTX_set_cert_verify_callback() prototype, the callback
   declaration has been changed from
           int (*cb)()
   into
           int (*cb)(X509_STORE_CTX *,void *);
   in ssl_verify_cert_chain (ssl/ssl_cert.c), the call
           i=s->ctx->app_verify_callback(&ctx)
   has been changed into
           i=s->ctx->app_verify_callback(&ctx, s->ctx->app_verify_arg).

   To update applications using SSL_CTX_set_cert_verify_callback(),
   a dummy argument can be added to their callback functions.

   *D. K. Smetters <smetters@parc.xerox.com>*

 * Added the '4758cca' ENGINE to support IBM 4758 cards.

   *Maurice Gittens <maurice@gittens.nl>, touchups by Geoff Thorpe*

 * Add and OPENSSL_LOAD_CONF define which will cause
   OpenSSL_add_all_algorithms() to load the openssl.cnf config file.
   This allows older applications to transparently support certain
   OpenSSL features: such as crypto acceleration and dynamic ENGINE loading.
   Two new functions OPENSSL_add_all_algorithms_noconf() which will never
   load the config file and OPENSSL_add_all_algorithms_conf() which will
   always load it have also been added.

   *Steve Henson*

 * Add the OFB, CFB and CTR (all with 128 bit feedback) to AES.
   Adjust NIDs and EVP layer.

   *Stephen Sprunk <stephen@sprunk.org> and Richard Levitte*

 * Config modules support in openssl utility.

   Most commands now load modules from the config file,
   though in a few (such as version) this isn't done
   because it couldn't be used for anything.

   In the case of ca and req the config file used is
   the same as the utility itself: that is the -config
   command line option can be used to specify an
   alternative file.

   *Steve Henson*

 * Move default behaviour from OPENSSL_config(). If appname is NULL
   use "openssl_conf" if filename is NULL use default openssl config file.

   *Steve Henson*

 * Add an argument to OPENSSL_config() to allow the use of an alternative
   config section name. Add a new flag to tolerate a missing config file
   and move code to CONF_modules_load_file().

   *Steve Henson*

 * Support for crypto accelerator cards from Accelerated Encryption
   Processing, www.aep.ie.  (Use engine 'aep')
   The support was copied from 0.9.6c [engine] and adapted/corrected
   to work with the new engine framework.

   *AEP Inc. and Richard Levitte*

 * Support for SureWare crypto accelerator cards from Baltimore
   Technologies.  (Use engine 'sureware')
   The support was copied from 0.9.6c [engine] and adapted
   to work with the new engine framework.

   *Richard Levitte*

 * Have the CHIL engine fork-safe (as defined by nCipher) and actually
   make the newer ENGINE framework commands for the CHIL engine work.

   *Toomas Kiisk <vix@cyber.ee> and Richard Levitte*

 * Make it possible to produce shared libraries on ReliantUNIX.

   *Robert Dahlem <Robert.Dahlem@ffm2.siemens.de> via Richard Levitte*

 * Add the configuration target debug-linux-ppro.
   Make 'openssl rsa' use the general key loading routines
   implemented in `apps.c`, and make those routines able to
   handle the key format FORMAT_NETSCAPE and the variant
   FORMAT_IISSGC.

   *Toomas Kiisk <vix@cyber.ee> via Richard Levitte*

 * Fix a crashbug and a logic bug in hwcrhk_load_pubkey().

   *Toomas Kiisk <vix@cyber.ee> via Richard Levitte*

 * Add -keyform to rsautl, and document -engine.

   *Richard Levitte, inspired by Toomas Kiisk <vix@cyber.ee>*

 * Change BIO_new_file (crypto/bio/bss_file.c) to use new
   BIO_R_NO_SUCH_FILE error code rather than the generic
   ERR_R_SYS_LIB error code if fopen() fails with ENOENT.

   *Ben Laurie*

 * Add new functions
           ERR_peek_last_error
           ERR_peek_last_error_line
           ERR_peek_last_error_line_data.
   These are similar to
           ERR_peek_error
           ERR_peek_error_line
           ERR_peek_error_line_data,
   but report on the latest error recorded rather than the first one
   still in the error queue.

   *Ben Laurie, Bodo Moeller*

 * default_algorithms option in ENGINE config module. This allows things
   like:
   default_algorithms = ALL
   default_algorithms = RSA, DSA, RAND, CIPHERS, DIGESTS

   *Steve Henson*

 * Preliminary ENGINE config module.

   *Steve Henson*

 * New experimental application configuration code.

   *Steve Henson*

 * Change the AES code to follow the same name structure as all other
   symmetric ciphers, and behave the same way.  Move everything to
   the directory crypto/aes, thereby obsoleting crypto/rijndael.

   *Stephen Sprunk <stephen@sprunk.org> and Richard Levitte*

 * SECURITY: remove unsafe setjmp/signal interaction from ui_openssl.c.

   *Ben Laurie and Theo de Raadt*

 * Add option to output public keys in req command.

   *Massimiliano Pala madwolf@openca.org*

 * Use wNAFs in EC_POINTs_mul() for improved efficiency
   (up to about 10% better than before for P-192 and P-224).

   *Bodo Moeller*

 * New functions/macros

           SSL_CTX_set_msg_callback(ctx, cb)
           SSL_CTX_set_msg_callback_arg(ctx, arg)
           SSL_set_msg_callback(ssl, cb)
           SSL_set_msg_callback_arg(ssl, arg)

   to request calling a callback function

           void cb(int write_p, int version, int content_type,
                   const void *buf, size_t len, SSL *ssl, void *arg)

   whenever a protocol message has been completely received
   (write_p == 0) or sent (write_p == 1).  Here 'version' is the
   protocol version  according to which the SSL library interprets
   the current protocol message (SSL2_VERSION, SSL3_VERSION, or
   TLS1_VERSION).  'content_type' is 0 in the case of SSL 2.0, or
   the content type as defined in the SSL 3.0/TLS 1.0 protocol
   specification (change_cipher_spec(20), alert(21), handshake(22)).
   'buf' and 'len' point to the actual message, 'ssl' to the
   SSL object, and 'arg' is the application-defined value set by
   SSL[_CTX]_set_msg_callback_arg().

   'openssl s_client' and 'openssl s_server' have new '-msg' options
   to enable a callback that displays all protocol messages.

   *Bodo Moeller*

 * Change the shared library support so shared libraries are built as
   soon as the corresponding static library is finished, and thereby get
   openssl and the test programs linked against the shared library.
   This still only happens when the keyword "shard" has been given to
   the configuration scripts.

   NOTE: shared library support is still an experimental thing, and
   backward binary compatibility is still not guaranteed.

   *"Maciej W. Rozycki" <macro@ds2.pg.gda.pl> and Richard Levitte*

 * Add support for Subject Information Access extension.

   *Peter Sylvester <Peter.Sylvester@EdelWeb.fr>*

 * Make BUF_MEM_grow() behaviour more consistent: Initialise to zero
   additional bytes when new memory had to be allocated, not just
   when reusing an existing buffer.

   *Bodo Moeller*

 * New command line and configuration option 'utf8' for the req command.
   This allows field values to be specified as UTF8 strings.

   *Steve Henson*

 * Add -multi and -mr options to "openssl speed" - giving multiple parallel
   runs for the former and machine-readable output for the latter.

   *Ben Laurie*

 * Add '-noemailDN' option to 'openssl ca'.  This prevents inclusion
   of the e-mail address in the DN (i.e., it will go into a certificate
   extension only).  The new configuration file option 'email_in_dn = no'
   has the same effect.

   *Massimiliano Pala madwolf@openca.org*

 * Change all functions with names starting with `des_` to be starting
   with `DES_` instead.  Add wrappers that are compatible with libdes,
   but are named `_ossl_old_des_*`.  Finally, add macros that map the
   `des_*` symbols to the corresponding `_ossl_old_des_*` if libdes
   compatibility is desired.  If OpenSSL 0.9.6c compatibility is
   desired, the `des_*` symbols will be mapped to `DES_*`, with one
   exception.

   Since we provide two compatibility mappings, the user needs to
   define the macro OPENSSL_DES_LIBDES_COMPATIBILITY if libdes
   compatibility is desired.  The default (i.e., when that macro
   isn't defined) is OpenSSL 0.9.6c compatibility.

   There are also macros that enable and disable the support of old
   des functions altogether.  Those are OPENSSL_ENABLE_OLD_DES_SUPPORT
   and OPENSSL_DISABLE_OLD_DES_SUPPORT.  If none or both of those
   are defined, the default will apply: to support the old des routines.

   In either case, one must include openssl/des.h to get the correct
   definitions.  Do not try to just include openssl/des_old.h, that
   won't work.

   NOTE: This is a major break of an old API into a new one.  Software
   authors are encouraged to switch to the `DES_` style functions.  Some
   time in the future, des_old.h and the libdes compatibility functions
   will be disable (i.e. OPENSSL_DISABLE_OLD_DES_SUPPORT will be the
   default), and then completely removed.

   *Richard Levitte*

 * Test for certificates which contain unsupported critical extensions.
   If such a certificate is found during a verify operation it is
   rejected by default: this behaviour can be overridden by either
   handling the new error X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION or
   by setting the verify flag X509_V_FLAG_IGNORE_CRITICAL. A new function
   X509_supported_extension() has also been added which returns 1 if a
   particular extension is supported.

   *Steve Henson*

 * Modify the behaviour of EVP cipher functions in similar way to digests
   to retain compatibility with existing code.

   *Steve Henson*

 * Modify the behaviour of EVP_DigestInit() and EVP_DigestFinal() to retain
   compatibility with existing code. In particular the 'ctx' parameter does
   not have to be to be initialized before the call to EVP_DigestInit() and
   it is tidied up after a call to EVP_DigestFinal(). New function
   EVP_DigestFinal_ex() which does not tidy up the ctx. Similarly function
   EVP_MD_CTX_copy() changed to not require the destination to be
   initialized valid and new function EVP_MD_CTX_copy_ex() added which
   requires the destination to be valid.

   Modify all the OpenSSL digest calls to use EVP_DigestInit_ex(),
   EVP_DigestFinal_ex() and EVP_MD_CTX_copy_ex().

   *Steve Henson*

 * Change ssl3_get_message (ssl/s3_both.c) and the functions using it
   so that complete 'Handshake' protocol structures are kept in memory
   instead of overwriting 'msg_type' and 'length' with 'body' data.

   *Bodo Moeller*

 * Add an implementation of SSL_add_dir_cert_subjects_to_stack for Win32.

   *Massimo Santin via Richard Levitte*

 * Major restructuring to the underlying ENGINE code. This includes
   reduction of linker bloat, separation of pure "ENGINE" manipulation
   (initialisation, etc) from functionality dealing with implementations
   of specific crypto interfaces. This change also introduces integrated
   support for symmetric ciphers and digest implementations - so ENGINEs
   can now accelerate these by providing EVP_CIPHER and EVP_MD
   implementations of their own. This is detailed in
   [crypto/engine/README.md](crypto/engine/README.md)
   as it couldn't be adequately described here. However, there are a few
   API changes worth noting - some RSA, DSA, DH, and RAND functions that
   were changed in the original introduction of ENGINE code have now
   reverted back - the hooking from this code to ENGINE is now a good
   deal more passive and at run-time, operations deal directly with
   RSA_METHODs, DSA_METHODs (etc) as they did before, rather than
   dereferencing through an ENGINE pointer any more. Also, the ENGINE
   functions dealing with `BN_MOD_EXP[_CRT]` handlers have been removed -
   they were not being used by the framework as there is no concept of a
   BIGNUM_METHOD and they could not be generalised to the new
   'ENGINE_TABLE' mechanism that underlies the new code. Similarly,
   ENGINE_cpy() has been removed as it cannot be consistently defined in
   the new code.

   *Geoff Thorpe*

 * Change ASN1_GENERALIZEDTIME_check() to allow fractional seconds.

   *Steve Henson*

 * Change mkdef.pl to sort symbols that get the same entry number,
   and make sure the automatically generated functions `ERR_load_*`
   become part of libeay.num as well.

   *Richard Levitte*

 * New function SSL_renegotiate_pending().  This returns true once
   renegotiation has been requested (either SSL_renegotiate() call
   or HelloRequest/ClientHello received from the peer) and becomes
   false once a handshake has been completed.
   (For servers, SSL_renegotiate() followed by SSL_do_handshake()
   sends a HelloRequest, but does not ensure that a handshake takes
   place.  SSL_renegotiate_pending() is useful for checking if the
   client has followed the request.)

   *Bodo Moeller*

 * New SSL option SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION.
   By default, clients may request session resumption even during
   renegotiation (if session ID contexts permit); with this option,
   session resumption is possible only in the first handshake.

   SSL_OP_ALL is now 0x00000FFFL instead of 0x000FFFFFL.  This makes
   more bits available for options that should not be part of
   SSL_OP_ALL (such as SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION).

   *Bodo Moeller*

 * Add some demos for certificate and certificate request creation.

   *Steve Henson*

 * Make maximum certificate chain size accepted from the peer application
   settable (`SSL*_get/set_max_cert_list()`), as proposed by
   "Douglas E. Engert" <deengert@anl.gov>.

   *Lutz Jaenicke*

 * Add support for shared libraries for Unixware-7
   (Boyd Lynn Gerber <gerberb@zenez.com>).

   *Lutz Jaenicke*

 * Add a "destroy" handler to ENGINEs that allows structural cleanup to
   be done prior to destruction. Use this to unload error strings from
   ENGINEs that load their own error strings. NB: This adds two new API
   functions to "get" and "set" this destroy handler in an ENGINE.

   *Geoff Thorpe*

 * Alter all existing ENGINE implementations (except "openssl" and
   "openbsd") to dynamically instantiate their own error strings. This
   makes them more flexible to be built both as statically-linked ENGINEs
   and self-contained shared-libraries loadable via the "dynamic" ENGINE.
   Also, add stub code to each that makes building them as self-contained
   shared-libraries easier (see [README-Engine.md](README-Engine.md)).

   *Geoff Thorpe*

 * Add a "dynamic" ENGINE that provides a mechanism for binding ENGINE
   implementations into applications that are completely implemented in
   self-contained shared-libraries. The "dynamic" ENGINE exposes control
   commands that can be used to configure what shared-library to load and
   to control aspects of the way it is handled. Also, made an update to
   the [README-Engine.md](README-Engine.md) file
   that brings its information up-to-date and
   provides some information and instructions on the "dynamic" ENGINE
   (ie. how to use it, how to build "dynamic"-loadable ENGINEs, etc).

   *Geoff Thorpe*

 * Make it possible to unload ranges of ERR strings with a new
   "ERR_unload_strings" function.

   *Geoff Thorpe*

 * Add a copy() function to EVP_MD.

   *Ben Laurie*

 * Make EVP_MD routines take a context pointer instead of just the
   md_data void pointer.

   *Ben Laurie*

 * Add flags to EVP_MD and EVP_MD_CTX. EVP_MD_FLAG_ONESHOT indicates
   that the digest can only process a single chunk of data
   (typically because it is provided by a piece of
   hardware). EVP_MD_CTX_FLAG_ONESHOT indicates that the application
   is only going to provide a single chunk of data, and hence the
   framework needn't accumulate the data for oneshot drivers.

   *Ben Laurie*

 * As with "ERR", make it possible to replace the underlying "ex_data"
   functions. This change also alters the storage and management of global
   ex_data state - it's now all inside ex_data.c and all "class" code (eg.
   RSA, BIO, SSL_CTX, etc) no longer stores its own STACKS and per-class
   index counters. The API functions that use this state have been changed
   to take a "class_index" rather than pointers to the class's local STACK
   and counter, and there is now an API function to dynamically create new
   classes. This centralisation allows us to (a) plug a lot of the
   thread-safety problems that existed, and (b) makes it possible to clean
   up all allocated state using "CRYPTO_cleanup_all_ex_data()". W.r.t. (b)
   such data would previously have always leaked in application code and
   workarounds were in place to make the memory debugging turn a blind eye
   to it. Application code that doesn't use this new function will still
   leak as before, but their memory debugging output will announce it now
   rather than letting it slide.

   Besides the addition of CRYPTO_cleanup_all_ex_data(), another API change
   induced by the "ex_data" overhaul is that X509_STORE_CTX_init() now
   has a return value to indicate success or failure.

   *Geoff Thorpe*

 * Make it possible to replace the underlying "ERR" functions such that the
   global state (2 LHASH tables and 2 locks) is only used by the "default"
   implementation. This change also adds two functions to "get" and "set"
   the implementation prior to it being automatically set the first time
   any other ERR function takes place. Ie. an application can call "get",
   pass the return value to a module it has just loaded, and that module
   can call its own "set" function using that value. This means the
   module's "ERR" operations will use (and modify) the error state in the
   application and not in its own statically linked copy of OpenSSL code.

   *Geoff Thorpe*

 * Give DH, DSA, and RSA types their own `*_up_ref()` function to increment
   reference counts. This performs normal REF_PRINT/REF_CHECK macros on
   the operation, and provides a more encapsulated way for external code
   (crypto/evp/ and ssl/) to do this. Also changed the evp and ssl code
   to use these functions rather than manually incrementing the counts.

   Also rename "DSO_up()" function to more descriptive "DSO_up_ref()".

   *Geoff Thorpe*

 * Add EVP test program.

   *Ben Laurie*

 * Add symmetric cipher support to ENGINE. Expect the API to change!

   *Ben Laurie*

 * New CRL functions: X509_CRL_set_version(), X509_CRL_set_issuer_name()
   X509_CRL_set_lastUpdate(), X509_CRL_set_nextUpdate(), X509_CRL_sort(),
   X509_REVOKED_set_serialNumber(), and X509_REVOKED_set_revocationDate().
   These allow a CRL to be built without having to access X509_CRL fields
   directly. Modify 'ca' application to use new functions.

   *Steve Henson*

 * Move SSL_OP_TLS_ROLLBACK_BUG out of the SSL_OP_ALL list of recommended
   bug workarounds. Rollback attack detection is a security feature.
   The problem will only arise on OpenSSL servers when TLSv1 is not
   available (sslv3_server_method() or SSL_OP_NO_TLSv1).
   Software authors not wanting to support TLSv1 will have special reasons
   for their choice and can explicitly enable this option.

   *Bodo Moeller, Lutz Jaenicke*

 * Rationalise EVP so it can be extended: don't include a union of
   cipher/digest structures, add init/cleanup functions for EVP_MD_CTX
   (similar to those existing for EVP_CIPHER_CTX).
   Usage example:

           EVP_MD_CTX md;

           EVP_MD_CTX_init(&md);             /* new function call */
           EVP_DigestInit(&md, EVP_sha1());
           EVP_DigestUpdate(&md, in, len);
           EVP_DigestFinal(&md, out, NULL);
           EVP_MD_CTX_cleanup(&md);          /* new function call */

   *Ben Laurie*

 * Make DES key schedule conform to the usual scheme, as well as
   correcting its structure. This means that calls to DES functions
   now have to pass a pointer to a des_key_schedule instead of a
   plain des_key_schedule (which was actually always a pointer
   anyway): E.g.,

           des_key_schedule ks;

           des_set_key_checked(..., &ks);
           des_ncbc_encrypt(..., &ks, ...);

   (Note that a later change renames 'des_...' into 'DES_...'.)

   *Ben Laurie*

 * Initial reduction of linker bloat: the use of some functions, such as
   PEM causes large amounts of unused functions to be linked in due to
   poor organisation. For example pem_all.c contains every PEM function
   which has a knock on effect of linking in large amounts of (unused)
   ASN1 code. Grouping together similar functions and splitting unrelated
   functions prevents this.

   *Steve Henson*

 * Cleanup of EVP macros.

   *Ben Laurie*

 * Change historical references to `{NID,SN,LN}_des_ede` and ede3 to add the
   correct `_ecb suffix`.

   *Ben Laurie*

 * Add initial OCSP responder support to ocsp application. The
   revocation information is handled using the text based index
   use by the ca application. The responder can either handle
   requests generated internally, supplied in files (for example
   via a CGI script) or using an internal minimal server.

   *Steve Henson*

 * Add configuration choices to get zlib compression for TLS.

   *Richard Levitte*

 * Changes to Kerberos SSL for RFC 2712 compliance:
   1. Implemented real KerberosWrapper, instead of just using
      KRB5 AP_REQ message.  [Thanks to Simon Wilkinson <sxw@sxw.org.uk>]
   2. Implemented optional authenticator field of KerberosWrapper.

   Added openssl-style ASN.1 macros for Kerberos ticket, ap_req,
   and authenticator structs; see crypto/krb5/.

   Generalized Kerberos calls to support multiple Kerberos libraries.
   *Vern Staats <staatsvr@asc.hpc.mil>, Jeffrey Altman <jaltman@columbia.edu>
   via Richard Levitte*

 * Cause 'openssl speed' to use fully hard-coded DSA keys as it
   already does with RSA. testdsa.h now has 'priv_key/pub_key'
   values for each of the key sizes rather than having just
   parameters (and 'speed' generating keys each time).

   *Geoff Thorpe*

 * Speed up EVP routines.
   Before:
crypt
pe              8 bytes     64 bytes    256 bytes   1024 bytes   8192 bytes
s-cbc           4408.85k     5560.51k     5778.46k     5862.20k     5825.16k
s-cbc           4389.55k     5571.17k     5792.23k     5846.91k     5832.11k
s-cbc           4394.32k     5575.92k     5807.44k     5848.37k     5841.30k
crypt
s-cbc           3482.66k     5069.49k     5496.39k     5614.16k     5639.28k
s-cbc           3480.74k     5068.76k     5510.34k     5609.87k     5635.52k
s-cbc           3483.72k     5067.62k     5504.60k     5708.01k     5724.80k
   After:
crypt
s-cbc           4660.16k     5650.19k     5807.19k     5827.13k     5783.32k
crypt
s-cbc           3624.96k     5258.21k     5530.91k     5624.30k     5628.26k

   *Ben Laurie*

 * Added the OS2-EMX target.

   *"Brian Havard" <brianh@kheldar.apana.org.au> and Richard Levitte*

 * Rewrite commands to use `NCONF` routines instead of the old `CONF`.
   New functions to support `NCONF` routines in extension code.
   New function `CONF_set_nconf()`
   to allow functions which take an `NCONF` to also handle the old `LHASH`
   structure: this means that the old `CONF` compatible routines can be
   retained (in particular w.rt. extensions) without having to duplicate the
   code. New function `X509V3_add_ext_nconf_sk()` to add extensions to a stack.

   *Steve Henson*

 * Enhance the general user interface with mechanisms for inner control
   and with possibilities to have yes/no kind of prompts.

   *Richard Levitte*

 * Change all calls to low-level digest routines in the library and
   applications to use EVP. Add missing calls to HMAC_cleanup() and
   don't assume HMAC_CTX can be copied using memcpy().

   *Verdon Walker <VWalker@novell.com>, Steve Henson*

 * Add the possibility to control engines through control names but with
   arbitrary arguments instead of just a string.
   Change the key loaders to take a UI_METHOD instead of a callback
   function pointer.  NOTE: this breaks binary compatibility with earlier
   versions of OpenSSL [engine].
   Adapt the nCipher code for these new conditions and add a card insertion
   callback.

   *Richard Levitte*

 * Enhance the general user interface with mechanisms to better support
   dialog box interfaces, application-defined prompts, the possibility
   to use defaults (for example default passwords from somewhere else)
   and interrupts/cancellations.

   *Richard Levitte*

 * Tidy up PKCS#12 attribute handling. Add support for the CSP name
   attribute in PKCS#12 files, add new -CSP option to pkcs12 utility.

   *Steve Henson*

 * Fix a memory leak in 'sk_dup()' in the case reallocation fails. (Also
   tidy up some unnecessarily weird code in 'sk_new()').

   *Geoff, reported by Diego Tartara <dtartara@novamens.com>*

 * Change the key loading routines for ENGINEs to use the same kind
   callback (pem_password_cb) as all other routines that need this
   kind of callback.

   *Richard Levitte*

 * Increase ENTROPY_NEEDED to 32 bytes, as Rijndael can operate with
   256 bit (=32 byte) keys. Of course seeding with more entropy bytes
   than this minimum value is recommended.

   *Lutz Jaenicke*

 * New random seeder for OpenVMS, using the system process statistics
   that are easily reachable.

   *Richard Levitte*

 * Windows apparently can't transparently handle global
   variables defined in DLLs. Initialisations such as:

           const ASN1_ITEM *it = &ASN1_INTEGER_it;

   won't compile. This is used by the any applications that need to
   declare their own ASN1 modules. This was fixed by adding the option
   EXPORT_VAR_AS_FN to all Win32 platforms, although this isn't strictly
   needed for static libraries under Win32.

   *Steve Henson*

 * New functions X509_PURPOSE_set() and X509_TRUST_set() to handle
   setting of purpose and trust fields. New X509_STORE trust and
   purpose functions and tidy up setting in other SSL functions.

   *Steve Henson*

 * Add copies of X509_STORE_CTX fields and callbacks to X509_STORE
   structure. These are inherited by X509_STORE_CTX when it is
   initialised. This allows various defaults to be set in the
   X509_STORE structure (such as flags for CRL checking and custom
   purpose or trust settings) for functions which only use X509_STORE_CTX
   internally such as S/MIME.

   Modify X509_STORE_CTX_purpose_inherit() so it only sets purposes and
   trust settings if they are not set in X509_STORE. This allows X509_STORE
   purposes and trust (in S/MIME for example) to override any set by default.

   Add command line options for CRL checking to smime, s_client and s_server
   applications.

   *Steve Henson*

 * Initial CRL based revocation checking. If the CRL checking flag(s)
   are set then the CRL is looked up in the X509_STORE structure and
   its validity and signature checked, then if the certificate is found
   in the CRL the verify fails with a revoked error.

   Various new CRL related callbacks added to X509_STORE_CTX structure.

   Command line options added to 'verify' application to support this.

   This needs some additional work, such as being able to handle multiple
   CRLs with different times, extension based lookup (rather than just
   by subject name) and ultimately more complete V2 CRL extension
   handling.

   *Steve Henson*

 * Add a general user interface API (crypto/ui/).  This is designed
   to replace things like des_read_password and friends (backward
   compatibility functions using this new API are provided).
   The purpose is to remove prompting functions from the DES code
   section as well as provide for prompting through dialog boxes in
   a window system and the like.

   *Richard Levitte*

 * Add "ex_data" support to ENGINE so implementations can add state at a
   per-structure level rather than having to store it globally.

   *Geoff*

 * Make it possible for ENGINE structures to be copied when retrieved by
   ENGINE_by_id() if the ENGINE specifies a new flag: ENGINE_FLAGS_BY_ID_COPY.
   This causes the "original" ENGINE structure to act like a template,
   analogous to the RSA vs. RSA_METHOD type of separation. Because of this
   operational state can be localised to each ENGINE structure, despite the
   fact they all share the same "methods". New ENGINE structures returned in
   this case have no functional references and the return value is the single
   structural reference. This matches the single structural reference returned
   by ENGINE_by_id() normally, when it is incremented on the pre-existing
   ENGINE structure.

   *Geoff*

 * Fix ASN1 decoder when decoding type ANY and V_ASN1_OTHER: since this
   needs to match any other type at all we need to manually clear the
   tag cache.

   *Steve Henson*

 * Changes to the "openssl engine" utility to include;
   - verbosity levels ('-v', '-vv', and '-vvv') that provide information
     about an ENGINE's available control commands.
   - executing control commands from command line arguments using the
     '-pre' and '-post' switches. '-post' is only used if '-t' is
     specified and the ENGINE is successfully initialised. The syntax for
     the individual commands are colon-separated, for example;
           openssl engine chil -pre FORK_CHECK:0 -pre SO_PATH:/lib/test.so

   *Geoff*

 * New dynamic control command support for ENGINEs. ENGINEs can now
   declare their own commands (numbers), names (strings), descriptions,
   and input types for run-time discovery by calling applications. A
   subset of these commands are implicitly classed as "executable"
   depending on their input type, and only these can be invoked through
   the new string-based API function ENGINE_ctrl_cmd_string(). (Eg. this
   can be based on user input, config files, etc). The distinction is
   that "executable" commands cannot return anything other than a boolean
   result and can only support numeric or string input, whereas some
   discoverable commands may only be for direct use through
   ENGINE_ctrl(), eg. supporting the exchange of binary data, function
   pointers, or other custom uses. The "executable" commands are to
   support parameterisations of ENGINE behaviour that can be
   unambiguously defined by ENGINEs and used consistently across any
   OpenSSL-based application. Commands have been added to all the
   existing hardware-supporting ENGINEs, noticeably "SO_PATH" to allow
   control over shared-library paths without source code alterations.

   *Geoff*

 * Changed all ENGINE implementations to dynamically allocate their
   ENGINEs rather than declaring them statically. Apart from this being
   necessary with the removal of the ENGINE_FLAGS_MALLOCED distinction,
   this also allows the implementations to compile without using the
   internal engine_int.h header.

   *Geoff*

 * Minor adjustment to "rand" code. RAND_get_rand_method() now returns a
   'const' value. Any code that should be able to modify a RAND_METHOD
   should already have non-const pointers to it (ie. they should only
   modify their own ones).

   *Geoff*

 * Made a variety of little tweaks to the ENGINE code.
   - "atalla" and "ubsec" string definitions were moved from header files
     to C code. "nuron" string definitions were placed in variables
     rather than hard-coded - allowing parameterisation of these values
     later on via ctrl() commands.
   - Removed unused "#if 0"'d code.
   - Fixed engine list iteration code so it uses ENGINE_free() to release
     structural references.
   - Constified the RAND_METHOD element of ENGINE structures.
   - Constified various get/set functions as appropriate and added
     missing functions (including a catch-all ENGINE_cpy that duplicates
     all ENGINE values onto a new ENGINE except reference counts/state).
   - Removed NULL parameter checks in get/set functions. Setting a method
     or function to NULL is a way of cancelling out a previously set
     value.  Passing a NULL ENGINE parameter is just plain stupid anyway
     and doesn't justify the extra error symbols and code.
   - Deprecate the ENGINE_FLAGS_MALLOCED define and move the area for
     flags from engine_int.h to engine.h.
   - Changed prototypes for ENGINE handler functions (init(), finish(),
     ctrl(), key-load functions, etc) to take an (ENGINE*) parameter.

   *Geoff*

 * Implement binary inversion algorithm for BN_mod_inverse in addition
   to the algorithm using long division.  The binary algorithm can be
   used only if the modulus is odd.  On 32-bit systems, it is faster
   only for relatively small moduli (roughly 20-30% for 128-bit moduli,
   roughly 5-15% for 256-bit moduli), so we use it only for moduli
   up to 450 bits.  In 64-bit environments, the binary algorithm
   appears to be advantageous for much longer moduli; here we use it
   for moduli up to 2048 bits.

   *Bodo Moeller*

 * Rewrite CHOICE field setting in ASN1_item_ex_d2i(). The old code
   could not support the combine flag in choice fields.

   *Steve Henson*

 * Add a 'copy_extensions' option to the 'ca' utility. This copies
   extensions from a certificate request to the certificate.

   *Steve Henson*

 * Allow multiple 'certopt' and 'nameopt' options to be separated
   by commas. Add 'namopt' and 'certopt' options to the 'ca' config
   file: this allows the display of the certificate about to be
   signed to be customised, to allow certain fields to be included
   or excluded and extension details. The old system didn't display
   multicharacter strings properly, omitted fields not in the policy
   and couldn't display additional details such as extensions.

   *Steve Henson*

 * Function EC_POINTs_mul for multiple scalar multiplication
   of an arbitrary number of elliptic curve points
           \sum scalars[i]*points[i],
   optionally including the generator defined for the EC_GROUP:
           scalar*generator +  \sum scalars[i]*points[i].

   EC_POINT_mul is a simple wrapper function for the typical case
   that the point list has just one item (besides the optional
   generator).

   *Bodo Moeller*

 * First EC_METHODs for curves over GF(p):

   EC_GFp_simple_method() uses the basic BN_mod_mul and BN_mod_sqr
   operations and provides various method functions that can also
   operate with faster implementations of modular arithmetic.

   EC_GFp_mont_method() reuses most functions that are part of
   EC_GFp_simple_method, but uses Montgomery arithmetic.

   *Bodo Moeller; point addition and point doubling
   implementation directly derived from source code provided by
   Lenka Fibikova <fibikova@exp-math.uni-essen.de>*

 * Framework for elliptic curves (crypto/ec/ec.h, crypto/ec/ec_lcl.h,
   crypto/ec/ec_lib.c):

   Curves are EC_GROUP objects (with an optional group generator)
   based on EC_METHODs that are built into the library.

   Points are EC_POINT objects based on EC_GROUP objects.

   Most of the framework would be able to handle curves over arbitrary
   finite fields, but as there are no obvious types for fields other
   than GF(p), some functions are limited to that for now.

   *Bodo Moeller*

 * Add the -HTTP option to s_server.  It is similar to -WWW, but requires
   that the file contains a complete HTTP response.

   *Richard Levitte*

 * Add the ec directory to mkdef.pl and mkfiles.pl. In mkdef.pl
   change the def and num file printf format specifier from "%-40sXXX"
   to "%-39s XXX". The latter will always guarantee a space after the
   field while the former will cause them to run together if the field
   is 40 of more characters long.

   *Steve Henson*

 * Constify the cipher and digest 'method' functions and structures
   and modify related functions to take constant EVP_MD and EVP_CIPHER
   pointers.

   *Steve Henson*

 * Hide BN_CTX structure details in bn_lcl.h instead of publishing them
   in <openssl/bn.h>.  Also further increase BN_CTX_NUM to 32.

   *Bodo Moeller*

 * Modify `EVP_Digest*()` routines so they now return values. Although the
   internal software routines can never fail additional hardware versions
   might.

   *Steve Henson*

 * Clean up crypto/err/err.h and change some error codes to avoid conflicts:

   Previously ERR_R_FATAL was too small and coincided with ERR_LIB_PKCS7
   (= ERR_R_PKCS7_LIB); it is now 64 instead of 32.

   ASN1 error codes
           ERR_R_NESTED_ASN1_ERROR
           ...
           ERR_R_MISSING_ASN1_EOS
   were 4 .. 9, conflicting with
           ERR_LIB_RSA (= ERR_R_RSA_LIB)
           ...
           ERR_LIB_PEM (= ERR_R_PEM_LIB).
   They are now 58 .. 63 (i.e., just below ERR_R_FATAL).

   Add new error code 'ERR_R_INTERNAL_ERROR'.

   *Bodo Moeller*

 * Don't overuse locks in crypto/err/err.c: For data retrieval, CRYPTO_r_lock
   suffices.

   *Bodo Moeller*

 * New option '-subj arg' for 'openssl req' and 'openssl ca'.  This
   sets the subject name for a new request or supersedes the
   subject name in a given request. Formats that can be parsed are
           'CN=Some Name, OU=myOU, C=IT'
   and
           'CN=Some Name/OU=myOU/C=IT'.

   Add options '-batch' and '-verbose' to 'openssl req'.

   *Massimiliano Pala <madwolf@hackmasters.net>*

 * Introduce the possibility to access global variables through
   functions on platform were that's the best way to handle exporting
   global variables in shared libraries.  To enable this functionality,
   one must configure with "EXPORT_VAR_AS_FN" or defined the C macro
   "OPENSSL_EXPORT_VAR_AS_FUNCTION" in crypto/opensslconf.h (the latter
   is normally done by Configure or something similar).

   To implement a global variable, use the macro OPENSSL_IMPLEMENT_GLOBAL
   in the source file (foo.c) like this:

           OPENSSL_IMPLEMENT_GLOBAL(int,foo)=1;
           OPENSSL_IMPLEMENT_GLOBAL(double,bar);

   To declare a global variable, use the macros OPENSSL_DECLARE_GLOBAL
   and OPENSSL_GLOBAL_REF in the header file (foo.h) like this:

           OPENSSL_DECLARE_GLOBAL(int,foo);
           #define foo OPENSSL_GLOBAL_REF(foo)
           OPENSSL_DECLARE_GLOBAL(double,bar);
           #define bar OPENSSL_GLOBAL_REF(bar)

   The #defines are very important, and therefore so is including the
   header file everywhere where the defined globals are used.

   The macro OPENSSL_EXPORT_VAR_AS_FUNCTION also affects the definition
   of ASN.1 items, but that structure is a bit different.

   The largest change is in util/mkdef.pl which has been enhanced with
   better and easier to understand logic to choose which symbols should
   go into the Windows .def files as well as a number of fixes and code
   cleanup (among others, algorithm keywords are now sorted
   lexicographically to avoid constant rewrites).

   *Richard Levitte*

 * In BN_div() keep a copy of the sign of 'num' before writing the
   result to 'rm' because if rm==num the value will be overwritten
   and produce the wrong result if 'num' is negative: this caused
   problems with BN_mod() and BN_nnmod().

   *Steve Henson*

 * Function OCSP_request_verify(). This checks the signature on an
   OCSP request and verifies the signer certificate. The signer
   certificate is just checked for a generic purpose and OCSP request
   trust settings.

   *Steve Henson*

 * Add OCSP_check_validity() function to check the validity of OCSP
   responses. OCSP responses are prepared in real time and may only
   be a few seconds old. Simply checking that the current time lies
   between thisUpdate and nextUpdate max reject otherwise valid responses
   caused by either OCSP responder or client clock inaccuracy. Instead
   we allow thisUpdate and nextUpdate to fall within a certain period of
   the current time. The age of the response can also optionally be
   checked. Two new options -validity_period and -status_age added to
   ocsp utility.

   *Steve Henson*

 * If signature or public key algorithm is unrecognized print out its
   OID rather that just UNKNOWN.

   *Steve Henson*

 * Change OCSP_cert_to_id() to tolerate a NULL subject certificate and
   OCSP_cert_id_new() a NULL serialNumber. This allows a partial certificate
   ID to be generated from the issuer certificate alone which can then be
   passed to OCSP_id_issuer_cmp().

   *Steve Henson*

 * New compilation option ASN1_ITEM_FUNCTIONS. This causes the new
   ASN1 modules to export functions returning ASN1_ITEM pointers
   instead of the ASN1_ITEM structures themselves. This adds several
   new macros which allow the underlying ASN1 function/structure to
   be accessed transparently. As a result code should not use ASN1_ITEM
   references directly (such as &X509_it) but instead use the relevant
   macros (such as ASN1_ITEM_rptr(X509)). This option is to allow
   use of the new ASN1 code on platforms where exporting structures
   is problematical (for example in shared libraries) but exporting
   functions returning pointers to structures is not.

   *Steve Henson*

 * Add support for overriding the generation of SSL/TLS session IDs.
   These callbacks can be registered either in an SSL_CTX or per SSL.
   The purpose of this is to allow applications to control, if they wish,
   the arbitrary values chosen for use as session IDs, particularly as it
   can be useful for session caching in multiple-server environments. A
   command-line switch for testing this (and any client code that wishes
   to use such a feature) has been added to "s_server".

   *Geoff Thorpe, Lutz Jaenicke*

 * Modify mkdef.pl to recognise and parse preprocessor conditionals
   of the form `#if defined(...) || defined(...) || ...` and
   `#if !defined(...) && !defined(...) && ...`.  This also avoids
   the growing number of special cases it was previously handling.

   *Richard Levitte*

 * Make all configuration macros available for application by making
   sure they are available in opensslconf.h, by giving them names starting
   with `OPENSSL_` to avoid conflicts with other packages and by making
   sure e_os2.h will cover all platform-specific cases together with
   opensslconf.h.
   Additionally, it is now possible to define configuration/platform-
   specific names (called "system identities").  In the C code, these
   are prefixed with `OPENSSL_SYSNAME_`.  e_os2.h will create another
   macro with the name beginning with `OPENSSL_SYS_`, which is determined
   from `OPENSSL_SYSNAME_*` or compiler-specific macros depending on
   what is available.

   *Richard Levitte*

 * New option -set_serial to 'req' and 'x509' this allows the serial
   number to use to be specified on the command line. Previously self
   signed certificates were hard coded with serial number 0 and the
   CA options of 'x509' had to use a serial number in a file which was
   auto incremented.

   *Steve Henson*

 * New options to 'ca' utility to support V2 CRL entry extensions.
   Currently CRL reason, invalidity date and hold instruction are
   supported. Add new CRL extensions to V3 code and some new objects.

   *Steve Henson*

 * New function EVP_CIPHER_CTX_set_padding() this is used to
   disable standard block padding (aka PKCS#5 padding) in the EVP
   API, which was previously mandatory. This means that the data is
   not padded in any way and so the total length much be a multiple
   of the block size, otherwise an error occurs.

   *Steve Henson*

 * Initial (incomplete) OCSP SSL support.

   *Steve Henson*

 * New function OCSP_parse_url(). This splits up a URL into its host,
   port and path components: primarily to parse OCSP URLs. New -url
   option to ocsp utility.

   *Steve Henson*

 * New nonce behavior. The return value of OCSP_check_nonce() now
   reflects the various checks performed. Applications can decide
   whether to tolerate certain situations such as an absent nonce
   in a response when one was present in a request: the ocsp application
   just prints out a warning. New function OCSP_add1_basic_nonce()
   this is to allow responders to include a nonce in a response even if
   the request is nonce-less.

   *Steve Henson*

 * Disable stdin buffering in `load_cert()` (`apps/apps.c`) so that no certs are
   skipped when using openssl x509 multiple times on a single input file,
   e.g. `(openssl x509 -out cert1; openssl x509 -out cert2) <certs`.

   *Bodo Moeller*

 * Make ASN1_UTCTIME_set_string() and ASN1_GENERALIZEDTIME_set_string()
   set string type: to handle setting ASN1_TIME structures. Fix ca
   utility to correctly initialize revocation date of CRLs.

   *Steve Henson*

 * New option SSL_OP_CIPHER_SERVER_PREFERENCE allows the server to override
   the clients preferred ciphersuites and rather use its own preferences.
   Should help to work around M$ SGC (Server Gated Cryptography) bug in
   Internet Explorer by ensuring unchanged hash method during stepup.
   (Also replaces the broken/deactivated SSL_OP_NON_EXPORT_FIRST option.)

   *Lutz Jaenicke*

 * Make mkdef.pl recognise all DECLARE_ASN1 macros, change rijndael
   to aes and add a new 'exist' option to print out symbols that don't
   appear to exist.

   *Steve Henson*

 * Additional options to ocsp utility to allow flags to be set and
   additional certificates supplied.

   *Steve Henson*

 * Add the option -VAfile to 'openssl ocsp', so the user can give the
   OCSP client a number of certificate to only verify the response
   signature against.

   *Richard Levitte*

 * Update Rijndael code to version 3.0 and change EVP AES ciphers to
   handle the new API. Currently only ECB, CBC modes supported. Add new
   AES OIDs.

   Add TLS AES ciphersuites as described in RFC3268, "Advanced
   Encryption Standard (AES) Ciphersuites for Transport Layer
   Security (TLS)".  (In beta versions of OpenSSL 0.9.7, these were
   not enabled by default and were not part of the "ALL" ciphersuite
   alias because they were not yet official; they could be
   explicitly requested by specifying the "AESdraft" ciphersuite
   group alias.  In the final release of OpenSSL 0.9.7, the group
   alias is called "AES" and is part of "ALL".)

   *Ben Laurie, Steve  Henson, Bodo Moeller*

 * New function OCSP_copy_nonce() to copy nonce value (if present) from
   request to response.

   *Steve Henson*

 * Functions for OCSP responders. OCSP_request_onereq_count(),
   OCSP_request_onereq_get0(), OCSP_onereq_get0_id() and OCSP_id_get0_info()
   extract information from a certificate request. OCSP_response_create()
   creates a response and optionally adds a basic response structure.
   OCSP_basic_add1_status() adds a complete single response to a basic
   response and returns the OCSP_SINGLERESP structure just added (to allow
   extensions to be included for example). OCSP_basic_add1_cert() adds a
   certificate to a basic response and OCSP_basic_sign() signs a basic
   response with various flags. New helper functions ASN1_TIME_check()
   (checks validity of ASN1_TIME structure) and ASN1_TIME_to_generalizedtime()
   (converts ASN1_TIME to GeneralizedTime).

   *Steve Henson*

 * Various new functions. EVP_Digest() combines EVP_Digest{Init,Update,Final}()
   in a single operation. X509_get0_pubkey_bitstr() extracts the public_key
   structure from a certificate. X509_pubkey_digest() digests the public_key
   contents: this is used in various key identifiers.

   *Steve Henson*

 * Make sk_sort() tolerate a NULL argument.

   *Steve Henson reported by Massimiliano Pala <madwolf@comune.modena.it>*

 * New OCSP verify flag OCSP_TRUSTOTHER. When set the "other" certificates
   passed by the function are trusted implicitly. If any of them signed the
   response then it is assumed to be valid and is not verified.

   *Steve Henson*

 * In PKCS7_set_type() initialise content_type in PKCS7_ENC_CONTENT
   to data. This was previously part of the PKCS7 ASN1 code. This
   was causing problems with OpenSSL created PKCS#12 and PKCS#7 structures.
   *Steve Henson, reported by Kenneth R. Robinette
                              <support@securenetterm.com>*

 * Add CRYPTO_push_info() and CRYPTO_pop_info() calls to new ASN1
   routines: without these tracing memory leaks is very painful.
   Fix leaks in PKCS12 and PKCS7 routines.

   *Steve Henson*

 * Make X509_time_adj() cope with the new behaviour of ASN1_TIME_new().
   Previously it initialised the 'type' argument to V_ASN1_UTCTIME which
   effectively meant GeneralizedTime would never be used. Now it
   is initialised to -1 but X509_time_adj() now has to check the value
   and use ASN1_TIME_set() if the value is not V_ASN1_UTCTIME or
   V_ASN1_GENERALIZEDTIME, without this it always uses GeneralizedTime.
   *Steve Henson, reported by Kenneth R. Robinette
                              <support@securenetterm.com>*

 * Fixes to BN_to_ASN1_INTEGER when bn is zero. This would previously
   result in a zero length in the ASN1_INTEGER structure which was
   not consistent with the structure when d2i_ASN1_INTEGER() was used
   and would cause ASN1_INTEGER_cmp() to fail. Enhance s2i_ASN1_INTEGER()
   to cope with hex and negative integers. Fix bug in i2a_ASN1_INTEGER()
   where it did not print out a minus for negative ASN1_INTEGER.

   *Steve Henson*

 * Add summary printout to ocsp utility. The various functions which
   convert status values to strings have been renamed to:
   OCSP_response_status_str(), OCSP_cert_status_str() and
   OCSP_crl_reason_str() and are no longer static. New options
   to verify nonce values and to disable verification. OCSP response
   printout format cleaned up.

   *Steve Henson*

 * Add additional OCSP certificate checks. These are those specified
   in RFC2560. This consists of two separate checks: the CA of the
   certificate being checked must either be the OCSP signer certificate
   or the issuer of the OCSP signer certificate. In the latter case the
   OCSP signer certificate must contain the OCSP signing extended key
   usage. This check is performed by attempting to match the OCSP
   signer or the OCSP signer CA to the issuerNameHash and issuerKeyHash
   in the OCSP_CERTID structures of the response.

   *Steve Henson*

 * Initial OCSP certificate verification added to OCSP_basic_verify()
   and related routines. This uses the standard OpenSSL certificate
   verify routines to perform initial checks (just CA validity) and
   to obtain the certificate chain. Then additional checks will be
   performed on the chain. Currently the root CA is checked to see
   if it is explicitly trusted for OCSP signing. This is used to set
   a root CA as a global signing root: that is any certificate that
   chains to that CA is an acceptable OCSP signing certificate.

   *Steve Henson*

 * New '-extfile ...' option to 'openssl ca' for reading X.509v3
   extensions from a separate configuration file.
   As when reading extensions from the main configuration file,
   the '-extensions ...' option may be used for specifying the
   section to use.

   *Massimiliano Pala <madwolf@comune.modena.it>*

 * New OCSP utility. Allows OCSP requests to be generated or
   read. The request can be sent to a responder and the output
   parsed, outputted or printed in text form. Not complete yet:
   still needs to check the OCSP response validity.

   *Steve Henson*

 * New subcommands for 'openssl ca':
   `openssl ca -status <serial>` prints the status of the cert with
   the given serial number (according to the index file).
   `openssl ca -updatedb` updates the expiry status of certificates
   in the index file.

   *Massimiliano Pala <madwolf@comune.modena.it>*

 * New '-newreq-nodes' command option to CA.pl.  This is like
   '-newreq', but calls 'openssl req' with the '-nodes' option
   so that the resulting key is not encrypted.

   *Damien Miller <djm@mindrot.org>*

 * New configuration for the GNU Hurd.

   *Jonathan Bartlett <johnnyb@wolfram.com> via Richard Levitte*

 * Initial code to implement OCSP basic response verify. This
   is currently incomplete. Currently just finds the signer's
   certificate and verifies the signature on the response.

   *Steve Henson*

 * New SSLeay_version code SSLEAY_DIR to determine the compiled-in
   value of OPENSSLDIR.  This is available via the new '-d' option
   to 'openssl version', and is also included in 'openssl version -a'.

   *Bodo Moeller*

 * Allowing defining memory allocation callbacks that will be given
   file name and line number information in additional arguments
   (a `const char*` and an int).  The basic functionality remains, as
   well as the original possibility to just replace malloc(),
   realloc() and free() by functions that do not know about these
   additional arguments.  To register and find out the current
   settings for extended allocation functions, the following
   functions are provided:

           CRYPTO_set_mem_ex_functions
           CRYPTO_set_locked_mem_ex_functions
           CRYPTO_get_mem_ex_functions
           CRYPTO_get_locked_mem_ex_functions

   These work the same way as CRYPTO_set_mem_functions and friends.
   `CRYPTO_get_[locked_]mem_functions` now writes 0 where such an
   extended allocation function is enabled.
   Similarly, `CRYPTO_get_[locked_]mem_ex_functions` writes 0 where
   a conventional allocation function is enabled.

   *Richard Levitte, Bodo Moeller*

 * Finish off removing the remaining LHASH function pointer casts.
   There should no longer be any prototype-casting required when using
   the LHASH abstraction, and any casts that remain are "bugs". See
   the callback types and macros at the head of lhash.h for details
   (and "OBJ_cleanup" in crypto/objects/obj_dat.c as an example).

   *Geoff Thorpe*

 * Add automatic query of EGD sockets in RAND_poll() for the unix variant.
   If /dev/[u]random devices are not available or do not return enough
   entropy, EGD style sockets (served by EGD or PRNGD) will automatically
   be queried.
   The locations /var/run/egd-pool, /dev/egd-pool, /etc/egd-pool, and
   /etc/entropy will be queried once each in this sequence, querying stops
   when enough entropy was collected without querying more sockets.

   *Lutz Jaenicke*

 * Change the Unix RAND_poll() variant to be able to poll several
   random devices, as specified by DEVRANDOM, until a sufficient amount
   of data has been collected.   We spend at most 10 ms on each file
   (select timeout) and read in non-blocking mode.  DEVRANDOM now
   defaults to the list "/dev/urandom", "/dev/random", "/dev/srandom"
   (previously it was just the string "/dev/urandom"), so on typical
   platforms the 10 ms delay will never occur.
   Also separate out the Unix variant to its own file, rand_unix.c.
   For VMS, there's a currently-empty rand_vms.c.

   *Richard Levitte*

 * Move OCSP client related routines to ocsp_cl.c. These
   provide utility functions which an application needing
   to issue a request to an OCSP responder and analyse the
   response will typically need: as opposed to those which an
   OCSP responder itself would need which will be added later.

   OCSP_request_sign() signs an OCSP request with an API similar
   to PKCS7_sign(). OCSP_response_status() returns status of OCSP
   response. OCSP_response_get1_basic() extracts basic response
   from response. OCSP_resp_find_status(): finds and extracts status
   information from an OCSP_CERTID structure (which will be created
   when the request structure is built). These are built from lower
   level functions which work on OCSP_SINGLERESP structures but
   won't normally be used unless the application wishes to examine
   extensions in the OCSP response for example.

   Replace nonce routines with a pair of functions.
   OCSP_request_add1_nonce() adds a nonce value and optionally
   generates a random value. OCSP_check_nonce() checks the
   validity of the nonce in an OCSP response.

   *Steve Henson*

 * Change function OCSP_request_add() to OCSP_request_add0_id().
   This doesn't copy the supplied OCSP_CERTID and avoids the
   need to free up the newly created id. Change return type
   to OCSP_ONEREQ to return the internal OCSP_ONEREQ structure.
   This can then be used to add extensions to the request.
   Deleted OCSP_request_new(), since most of its functionality
   is now in OCSP_REQUEST_new() (and the case insensitive name
   clash) apart from the ability to set the request name which
   will be added elsewhere.

   *Steve Henson*

 * Update OCSP API. Remove obsolete extensions argument from
   various functions. Extensions are now handled using the new
   OCSP extension code. New simple OCSP HTTP function which
   can be used to send requests and parse the response.

   *Steve Henson*

 * Fix the PKCS#7 (S/MIME) code to work with new ASN1. Two new
   ASN1_ITEM structures help with sign and verify. PKCS7_ATTR_SIGN
   uses the special reorder version of SET OF to sort the attributes
   and reorder them to match the encoded order. This resolves a long
   standing problem: a verify on a PKCS7 structure just after signing
   it used to fail because the attribute order did not match the
   encoded order. PKCS7_ATTR_VERIFY does not reorder the attributes:
   it uses the received order. This is necessary to tolerate some broken
   software that does not order SET OF. This is handled by encoding
   as a SEQUENCE OF but using implicit tagging (with UNIVERSAL class)
   to produce the required SET OF.

   *Steve Henson*

 * Have mk1mf.pl generate the macros OPENSSL_BUILD_SHLIBCRYPTO and
   OPENSSL_BUILD_SHLIBSSL and use them appropriately in the header
   files to get correct declarations of the ASN.1 item variables.

   *Richard Levitte*

 * Rewrite of PKCS#12 code to use new ASN1 functionality. Replace many
   PKCS#12 macros with real functions. Fix two unrelated ASN1 bugs:
   asn1_check_tlen() would sometimes attempt to use 'ctx' when it was
   NULL and ASN1_TYPE was not dereferenced properly in asn1_ex_c2i().
   New ASN1 macro: DECLARE_ASN1_ITEM() which just declares the relevant
   ASN1_ITEM and no wrapper functions.

   *Steve Henson*

 * New functions or ASN1_item_d2i_fp() and ASN1_item_d2i_bio(). These
   replace the old function pointer based I/O routines. Change most of
   the `*_d2i_bio()` and `*_d2i_fp()` functions to use these.

   *Steve Henson*

 * Enhance mkdef.pl to be more accepting about spacing in C preprocessor
   lines, recognize more "algorithms" that can be deselected, and make
   it complain about algorithm deselection that isn't recognised.

   *Richard Levitte*

 * New ASN1 functions to handle dup, sign, verify, digest, pack and
   unpack operations in terms of ASN1_ITEM. Modify existing wrappers
   to use new functions. Add NO_ASN1_OLD which can be set to remove
   some old style ASN1 functions: this can be used to determine if old
   code will still work when these eventually go away.

   *Steve Henson*

 * New extension functions for OCSP structures, these follow the
   same conventions as certificates and CRLs.

   *Steve Henson*

 * New function X509V3_add1_i2d(). This automatically encodes and
   adds an extension. Its behaviour can be customised with various
   flags to append, replace or delete. Various wrappers added for
   certificates and CRLs.

   *Steve Henson*

 * Fix to avoid calling the underlying ASN1 print routine when
   an extension cannot be parsed. Correct a typo in the
   OCSP_SERVICELOC extension. Tidy up print OCSP format.

   *Steve Henson*

 * Make mkdef.pl parse some of the ASN1 macros and add appropriate
   entries for variables.

   *Steve Henson*

 * Add functionality to `apps/openssl.c` for detecting locking
   problems: As the program is single-threaded, all we have
   to do is register a locking callback using an array for
   storing which locks are currently held by the program.

   *Bodo Moeller*

 * Use a lock around the call to CRYPTO_get_ex_new_index() in
   SSL_get_ex_data_X509_STORE_idx(), which is used in
   ssl_verify_cert_chain() and thus can be called at any time
   during TLS/SSL handshakes so that thread-safety is essential.
   Unfortunately, the ex_data design is not at all suited
   for multi-threaded use, so it probably should be abolished.

   *Bodo Moeller*

 * Added Broadcom "ubsec" ENGINE to OpenSSL.

   *Broadcom, tweaked and integrated by Geoff Thorpe*

 * Move common extension printing code to new function
   X509V3_print_extensions(). Reorganise OCSP print routines and
   implement some needed OCSP ASN1 functions. Add OCSP extensions.

   *Steve Henson*

 * New function X509_signature_print() to remove duplication in some
   print routines.

   *Steve Henson*

 * Add a special meaning when SET OF and SEQUENCE OF flags are both
   set (this was treated exactly the same as SET OF previously). This
   is used to reorder the STACK representing the structure to match the
   encoding. This will be used to get round a problem where a PKCS7
   structure which was signed could not be verified because the STACK
   order did not reflect the encoded order.

   *Steve Henson*

 * Reimplement the OCSP ASN1 module using the new code.

   *Steve Henson*

 * Update the X509V3 code to permit the use of an ASN1_ITEM structure
   for its ASN1 operations. The old style function pointers still exist
   for now but they will eventually go away.

   *Steve Henson*

 * Merge in replacement ASN1 code from the ASN1 branch. This almost
   completely replaces the old ASN1 functionality with a table driven
   encoder and decoder which interprets an ASN1_ITEM structure describing
   the ASN1 module. Compatibility with the existing ASN1 API (i2d,d2i) is
   largely maintained. Almost all of the old asn1_mac.h macro based ASN1
   has also been converted to the new form.

   *Steve Henson*

 * Change BN_mod_exp_recp so that negative moduli are tolerated
   (the sign is ignored).  Similarly, ignore the sign in BN_MONT_CTX_set
   so that BN_mod_exp_mont and BN_mod_exp_mont_word work
   for negative moduli.

   *Bodo Moeller*

 * Fix BN_uadd and BN_usub: Always return non-negative results instead
   of not touching the result's sign bit.

   *Bodo Moeller*

 * BN_div bugfix: If the result is 0, the sign (res->neg) must not be
   set.

   *Bodo Moeller*

 * Changed the LHASH code to use prototypes for callbacks, and created
   macros to declare and implement thin (optionally static) functions
   that provide type-safety and avoid function pointer casting for the
   type-specific callbacks.

   *Geoff Thorpe*

 * Added Kerberos Cipher Suites to be used with TLS, as written in
   RFC 2712.
   *Veers Staats <staatsvr@asc.hpc.mil>,
   Jeffrey Altman <jaltman@columbia.edu>, via Richard Levitte*

 * Reformat the FAQ so the different questions and answers can be divided
   in sections depending on the subject.

   *Richard Levitte*

 * Have the zlib compression code load ZLIB.DLL dynamically under
   Windows.

   *Richard Levitte*

 * New function BN_mod_sqrt for computing square roots modulo a prime
   (using the probabilistic Tonelli-Shanks algorithm unless
   p == 3 (mod 4)  or  p == 5 (mod 8),  which are cases that can
   be handled deterministically).

   *Lenka Fibikova <fibikova@exp-math.uni-essen.de>, Bodo Moeller*

 * Make BN_mod_inverse faster by explicitly handling small quotients
   in the Euclid loop. (Speed gain about 20% for small moduli [256 or
   512 bits], about 30% for larger ones [1024 or 2048 bits].)

   *Bodo Moeller*

 * New function BN_kronecker.

   *Bodo Moeller*

 * Fix BN_gcd so that it works on negative inputs; the result is
   positive unless both parameters are zero.
   Previously something reasonably close to an infinite loop was
   possible because numbers could be growing instead of shrinking
   in the implementation of Euclid's algorithm.

   *Bodo Moeller*

 * Fix BN_is_word() and BN_is_one() macros to take into account the
   sign of the number in question.

   Fix BN_is_word(a,w) to work correctly for w == 0.

   The old BN_is_word(a,w) macro is now called BN_abs_is_word(a,w)
   because its test if the absolute value of 'a' equals 'w'.
   Note that BN_abs_is_word does *not* handle w == 0 reliably;
   it exists mostly for use in the implementations of BN_is_zero(),
   BN_is_one(), and BN_is_word().

   *Bodo Moeller*

 * New function BN_swap.

   *Bodo Moeller*

 * Use BN_nnmod instead of BN_mod in crypto/bn/bn_exp.c so that
   the exponentiation functions are more likely to produce reasonable
   results on negative inputs.

   *Bodo Moeller*

 * Change BN_mod_mul so that the result is always non-negative.
   Previously, it could be negative if one of the factors was negative;
   I don't think anyone really wanted that behaviour.

   *Bodo Moeller*

 * Move `BN_mod_...` functions into new file `crypto/bn/bn_mod.c`
   (except for exponentiation, which stays in `crypto/bn/bn_exp.c`,
   and `BN_mod_mul_reciprocal`, which stays in `crypto/bn/bn_recp.c`)
   and add new functions:

           BN_nnmod
           BN_mod_sqr
           BN_mod_add
           BN_mod_add_quick
           BN_mod_sub
           BN_mod_sub_quick
           BN_mod_lshift1
           BN_mod_lshift1_quick
           BN_mod_lshift
           BN_mod_lshift_quick

   These functions always generate non-negative results.

   `BN_nnmod` otherwise is `like BN_mod` (if `BN_mod` computes a remainder `r`
   such that `|m| < r < 0`, `BN_nnmod` will output `rem + |m|` instead).

   `BN_mod_XXX_quick(r, a, [b,] m)` generates the same result as
   `BN_mod_XXX(r, a, [b,] m, ctx)`, but requires that `a` [and  `b`]
   be reduced modulo `m`.

   *Lenka Fibikova <fibikova@exp-math.uni-essen.de>, Bodo Moeller*

<!--
   The following entry accidentally appeared in the CHANGES file
   distributed with OpenSSL 0.9.7.  The modifications described in
   it do *not* apply to OpenSSL 0.9.7.

 * Remove a few calls to bn_wexpand() in BN_sqr() (the one in there
   was actually never needed) and in BN_mul().  The removal in BN_mul()
   required a small change in bn_mul_part_recursive() and the addition
   of the functions bn_cmp_part_words(), bn_sub_part_words() and
   bn_add_part_words(), which do the same thing as bn_cmp_words(),
   bn_sub_words() and bn_add_words() except they take arrays with
   differing sizes.

   *Richard Levitte*
-->

 * In 'openssl passwd', verify passwords read from the terminal
   unless the '-salt' option is used (which usually means that
   verification would just waste user's time since the resulting
   hash is going to be compared with some given password hash)
   or the new '-noverify' option is used.

   This is an incompatible change, but it does not affect
   non-interactive use of 'openssl passwd' (passwords on the command
   line, '-stdin' option, '-in ...' option) and thus should not
   cause any problems.

   *Bodo Moeller*

 * Remove all references to RSAref, since there's no more need for it.

   *Richard Levitte*

 * Make DSO load along a path given through an environment variable
   (SHLIB_PATH) with shl_load().

   *Richard Levitte*

 * Constify the ENGINE code as a result of BIGNUM constification.
   Also constify the RSA code and most things related to it.  In a
   few places, most notable in the depth of the ASN.1 code, ugly
   casts back to non-const were required (to be solved at a later
   time)

   *Richard Levitte*

 * Make it so the openssl application has all engines loaded by default.

   *Richard Levitte*

 * Constify the BIGNUM routines a little more.

   *Richard Levitte*

 * Add the following functions:

           ENGINE_load_cswift()
           ENGINE_load_chil()
           ENGINE_load_atalla()
           ENGINE_load_nuron()
           ENGINE_load_builtin_engines()

   That way, an application can itself choose if external engines that
   are built-in in OpenSSL shall ever be used or not.  The benefit is
   that applications won't have to be linked with libdl or other dso
   libraries unless it's really needed.

   Changed 'openssl engine' to load all engines on demand.
   Changed the engine header files to avoid the duplication of some
   declarations (they differed!).

   *Richard Levitte*

 * 'openssl engine' can now list capabilities.

   *Richard Levitte*

 * Better error reporting in 'openssl engine'.

   *Richard Levitte*

 * Never call load_dh_param(NULL) in s_server.

   *Bodo Moeller*

 * Add engine application.  It can currently list engines by name and
   identity, and test if they are actually available.

   *Richard Levitte*

 * Improve RPM specification file by forcing symbolic linking and making
   sure the installed documentation is also owned by root.root.

   *Damien Miller <djm@mindrot.org>*

 * Give the OpenSSL applications more possibilities to make use of
   keys (public as well as private) handled by engines.

   *Richard Levitte*

 * Add OCSP code that comes from CertCo.

   *Richard Levitte*

 * Add VMS support for the Rijndael code.

   *Richard Levitte*

 * Added untested support for Nuron crypto accelerator.

   *Ben Laurie*

 * Add support for external cryptographic devices.  This code was
   previously distributed separately as the "engine" branch.

   *Geoff Thorpe, Richard Levitte*

 * Rework the filename-translation in the DSO code. It is now possible to
   have far greater control over how a "name" is turned into a filename
   depending on the operating environment and any oddities about the
   different shared library filenames on each system.

   *Geoff Thorpe*

 * Support threads on FreeBSD-elf in Configure.

   *Richard Levitte*

 * Fix for SHA1 assembly problem with MASM: it produces
   warnings about corrupt line number information when assembling
   with debugging information. This is caused by the overlapping
   of two sections.

   *Bernd Matthes <mainbug@celocom.de>, Steve Henson*

 * NCONF changes.
   NCONF_get_number() has no error checking at all.  As a replacement,
   NCONF_get_number_e() is defined (`_e` for "error checking") and is
   promoted strongly.  The old NCONF_get_number is kept around for
   binary backward compatibility.
   Make it possible for methods to load from something other than a BIO,
   by providing a function pointer that is given a name instead of a BIO.
   For example, this could be used to load configuration data from an
   LDAP server.

   *Richard Levitte*

 * Fix for non blocking accept BIOs. Added new I/O special reason
   BIO_RR_ACCEPT to cover this case. Previously use of accept BIOs
   with non blocking I/O was not possible because no retry code was
   implemented. Also added new SSL code SSL_WANT_ACCEPT to cover
   this case.

   *Steve Henson*

 * Added the beginnings of Rijndael support.

   *Ben Laurie*

 * Fix for bug in DirectoryString mask setting. Add support for
   X509_NAME_print_ex() in 'req' and X509_print_ex() function
   to allow certificate printing to more controllable, additional
   'certopt' option to 'x509' to allow new printing options to be
   set.

   *Steve Henson*

 * Clean old EAY MD5 hack from e_os.h.

   *Richard Levitte*

### Changes between 0.9.6l and 0.9.6m  [17 Mar 2004]

 * Fix null-pointer assignment in do_change_cipher_spec() revealed
   by using the Codenomicon TLS Test Tool ([CVE-2004-0079])

   *Joe Orton, Steve Henson*

### Changes between 0.9.6k and 0.9.6l  [04 Nov 2003]

 * Fix additional bug revealed by the NISCC test suite:

   Stop bug triggering large recursion when presented with
   certain ASN.1 tags ([CVE-2003-0851])

   *Steve Henson*

### Changes between 0.9.6j and 0.9.6k  [30 Sep 2003]

 * Fix various bugs revealed by running the NISCC test suite:

   Stop out of bounds reads in the ASN1 code when presented with
   invalid tags (CVE-2003-0543 and CVE-2003-0544).

   If verify callback ignores invalid public key errors don't try to check
   certificate signature with the NULL public key.

   *Steve Henson*

 * In ssl3_accept() (ssl/s3_srvr.c) only accept a client certificate
   if the server requested one: as stated in TLS 1.0 and SSL 3.0
   specifications.

   *Steve Henson*

 * In ssl3_get_client_hello() (ssl/s3_srvr.c), tolerate additional
   extra data after the compression methods not only for TLS 1.0
   but also for SSL 3.0 (as required by the specification).

   *Bodo Moeller; problem pointed out by Matthias Loepfe*

 * Change X509_certificate_type() to mark the key as exported/exportable
   when it's 512 *bits* long, not 512 bytes.

   *Richard Levitte*

### Changes between 0.9.6i and 0.9.6j  [10 Apr 2003]

 * Countermeasure against the Klima-Pokorny-Rosa extension of
   Bleichbacher's attack on PKCS #1 v1.5 padding: treat
   a protocol version number mismatch like a decryption error
   in ssl3_get_client_key_exchange (ssl/s3_srvr.c).

   *Bodo Moeller*

 * Turn on RSA blinding by default in the default implementation
   to avoid a timing attack. Applications that don't want it can call
   RSA_blinding_off() or use the new flag RSA_FLAG_NO_BLINDING.
   They would be ill-advised to do so in most cases.

   *Ben Laurie, Steve Henson, Geoff Thorpe, Bodo Moeller*

 * Change RSA blinding code so that it works when the PRNG is not
   seeded (in this case, the secret RSA exponent is abused as
   an unpredictable seed -- if it is not unpredictable, there
   is no point in blinding anyway).  Make RSA blinding thread-safe
   by remembering the creator's thread ID in rsa->blinding and
   having all other threads use local one-time blinding factors
   (this requires more computation than sharing rsa->blinding, but
   avoids excessive locking; and if an RSA object is not shared
   between threads, blinding will still be very fast).

   *Bodo Moeller*

### Changes between 0.9.6h and 0.9.6i  [19 Feb 2003]

 * In ssl3_get_record (ssl/s3_pkt.c), minimize information leaked
   via timing by performing a MAC computation even if incorrect
   block cipher padding has been found.  This is a countermeasure
   against active attacks where the attacker has to distinguish
   between bad padding and a MAC verification error. ([CVE-2003-0078])

   *Bodo Moeller; problem pointed out by Brice Canvel (EPFL),
   Alain Hiltgen (UBS), Serge Vaudenay (EPFL), and
   Martin Vuagnoux (EPFL, Ilion)*

### Changes between 0.9.6g and 0.9.6h  [5 Dec 2002]

 * New function OPENSSL_cleanse(), which is used to cleanse a section of
   memory from its contents.  This is done with a counter that will
   place alternating values in each byte.  This can be used to solve
   two issues: 1) the removal of calls to memset() by highly optimizing
   compilers, and 2) cleansing with other values than 0, since those can
   be read through on certain media, for example a swap space on disk.

   *Geoff Thorpe*

 * Bugfix: client side session caching did not work with external caching,
   because the session->cipher setting was not restored when reloading
   from the external cache. This problem was masked, when
   SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG (part of SSL_OP_ALL) was set.
   (Found by Steve Haslam <steve@araqnid.ddts.net>.)

   *Lutz Jaenicke*

 * Fix client_certificate (ssl/s2_clnt.c): The permissible total
   length of the REQUEST-CERTIFICATE message is 18 .. 34, not 17 .. 33.

   *Zeev Lieber <zeev-l@yahoo.com>*

 * Undo an undocumented change introduced in 0.9.6e which caused
   repeated calls to OpenSSL_add_all_ciphers() and
   OpenSSL_add_all_digests() to be ignored, even after calling
   EVP_cleanup().

   *Richard Levitte*

 * Change the default configuration reader to deal with last line not
   being properly terminated.

   *Richard Levitte*

 * Change X509_NAME_cmp() so it applies the special rules on handling
   DN values that are of type PrintableString, as well as RDNs of type
   emailAddress where the value has the type ia5String.

   *stefank@valicert.com via Richard Levitte*

 * Add a SSL_SESS_CACHE_NO_INTERNAL_STORE flag to take over half
   the job SSL_SESS_CACHE_NO_INTERNAL_LOOKUP was inconsistently
   doing, define a new flag (SSL_SESS_CACHE_NO_INTERNAL) to be
   the bitwise-OR of the two for use by the majority of applications
   wanting this behaviour, and update the docs. The documented
   behaviour and actual behaviour were inconsistent and had been
   changing anyway, so this is more a bug-fix than a behavioural
   change.

   *Geoff Thorpe, diagnosed by Nadav Har'El*

 * Don't impose a 16-byte length minimum on session IDs in ssl/s3_clnt.c
   (the SSL 3.0 and TLS 1.0 specifications allow any length up to 32 bytes).

   *Bodo Moeller*

 * Fix initialization code race conditions in
           SSLv23_method(),  SSLv23_client_method(),   SSLv23_server_method(),
           SSLv2_method(),   SSLv2_client_method(),    SSLv2_server_method(),
           SSLv3_method(),   SSLv3_client_method(),    SSLv3_server_method(),
           TLSv1_method(),   TLSv1_client_method(),    TLSv1_server_method(),
           ssl2_get_cipher_by_char(),
           ssl3_get_cipher_by_char().

   *Patrick McCormick <patrick@tellme.com>, Bodo Moeller*

 * Reorder cleanup sequence in SSL_CTX_free(): only remove the ex_data after
   the cached sessions are flushed, as the remove_cb() might use ex_data
   contents. Bug found by Sam Varshavchik <mrsam@courier-mta.com>
   (see [openssl.org #212]).

   *Geoff Thorpe, Lutz Jaenicke*

 * Fix typo in OBJ_txt2obj which incorrectly passed the content
   length, instead of the encoding length to d2i_ASN1_OBJECT.

   *Steve Henson*

### Changes between 0.9.6f and 0.9.6g  [9 Aug 2002]

 * [In 0.9.6g-engine release:]
   Fix crypto/engine/vendor_defns/cswift.h for WIN32 (use `_stdcall`).

   *Lynn Gazis <lgazis@rainbow.com>*

### Changes between 0.9.6e and 0.9.6f  [8 Aug 2002]

 * Fix ASN1 checks. Check for overflow by comparing with LONG_MAX
   and get fix the header length calculation.
   *Florian Weimer <Weimer@CERT.Uni-Stuttgart.DE>,
   Alon Kantor <alonk@checkpoint.com> (and others), Steve Henson*

 * Use proper error handling instead of 'assertions' in buffer
   overflow checks added in 0.9.6e.  This prevents DoS (the
   assertions could call abort()).

   *Arne Ansper <arne@ats.cyber.ee>, Bodo Moeller*

### Changes between 0.9.6d and 0.9.6e  [30 Jul 2002]

 * Add various sanity checks to asn1_get_length() to reject
   the ASN1 length bytes if they exceed sizeof(long), will appear
   negative or the content length exceeds the length of the
   supplied buffer.

   *Steve Henson, Adi Stav <stav@mercury.co.il>, James Yonan <jim@ntlp.com>*

 * Fix cipher selection routines: ciphers without encryption had no flags
   for the cipher strength set and where therefore not handled correctly
   by the selection routines (PR #130).

   *Lutz Jaenicke*

 * Fix EVP_dsa_sha macro.

   *Nils Larsch*

 * New option
        SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS
   for disabling the SSL 3.0/TLS 1.0 CBC vulnerability countermeasure
   that was added in OpenSSL 0.9.6d.

   As the countermeasure turned out to be incompatible with some
   broken SSL implementations, the new option is part of SSL_OP_ALL.
   SSL_OP_ALL is usually employed when compatibility with weird SSL
   implementations is desired (e.g. '-bugs' option to 's_client' and
   's_server'), so the new option is automatically set in many
   applications.

   *Bodo Moeller*

 * Changes in security patch:

   Changes marked "(CHATS)" were sponsored by the Defense Advanced
   Research Projects Agency (DARPA) and Air Force Research Laboratory,
   Air Force Materiel Command, USAF, under agreement number
   F30602-01-2-0537.

 * Add various sanity checks to asn1_get_length() to reject
   the ASN1 length bytes if they exceed sizeof(long), will appear
   negative or the content length exceeds the length of the
   supplied buffer. ([CVE-2002-0659])

   *Steve Henson, Adi Stav <stav@mercury.co.il>, James Yonan <jim@ntlp.com>*

 * Assertions for various potential buffer overflows, not known to
   happen in practice.

   *Ben Laurie (CHATS)*

 * Various temporary buffers to hold ASCII versions of integers were
   too small for 64 bit platforms. ([CVE-2002-0655])
   *Matthew Byng-Maddick <mbm@aldigital.co.uk> and Ben Laurie (CHATS)>*

 * Remote buffer overflow in SSL3 protocol - an attacker could
   supply an oversized session ID to a client. ([CVE-2002-0656])

   *Ben Laurie (CHATS)*

 * Remote buffer overflow in SSL2 protocol - an attacker could
   supply an oversized client master key. ([CVE-2002-0656])

   *Ben Laurie (CHATS)*

### Changes between 0.9.6c and 0.9.6d  [9 May 2002]

 * Fix crypto/asn1/a_sign.c so that 'parameters' is omitted (not
   encoded as NULL) with id-dsa-with-sha1.

   *Nils Larsch <nla@trustcenter.de>; problem pointed out by Bodo Moeller*

 * Check various `X509_...()` return values in `apps/req.c`.

   *Nils Larsch <nla@trustcenter.de>*

 * Fix BASE64 decode (EVP_DecodeUpdate) for data with CR/LF ended lines:
   an end-of-file condition would erroneously be flagged, when the CRLF
   was just at the end of a processed block. The bug was discovered when
   processing data through a buffering memory BIO handing the data to a
   BASE64-decoding BIO. Bug fund and patch submitted by Pavel Tsekov
   <ptsekov@syntrex.com> and Nedelcho Stanev.

   *Lutz Jaenicke*

 * Implement a countermeasure against a vulnerability recently found
   in CBC ciphersuites in SSL 3.0/TLS 1.0: Send an empty fragment
   before application data chunks to avoid the use of known IVs
   with data potentially chosen by the attacker.

   *Bodo Moeller*

 * Fix length checks in ssl3_get_client_hello().

   *Bodo Moeller*

 * TLS/SSL library bugfix: use s->s3->in_read_app_data differently
   to prevent ssl3_read_internal() from incorrectly assuming that
   ssl3_read_bytes() found application data while handshake
   processing was enabled when in fact s->s3->in_read_app_data was
   merely automatically cleared during the initial handshake.

   *Bodo Moeller; problem pointed out by Arne Ansper <arne@ats.cyber.ee>*

 * Fix object definitions for Private and Enterprise: they were not
   recognized in their shortname (=lowercase) representation. Extend
   obj_dat.pl to issue an error when using undefined keywords instead
   of silently ignoring the problem (Svenning Sorensen
   <sss@sss.dnsalias.net>).

   *Lutz Jaenicke*

 * Fix DH_generate_parameters() so that it works for 'non-standard'
   generators, i.e. generators other than 2 and 5.  (Previously, the
   code did not properly initialise the 'add' and 'rem' values to
   BN_generate_prime().)

   In the new general case, we do not insist that 'generator' is
   actually a primitive root: This requirement is rather pointless;
   a generator of the order-q subgroup is just as good, if not
   better.

   *Bodo Moeller*

 * Map new X509 verification errors to alerts. Discovered and submitted by
   Tom Wu <tom@arcot.com>.

   *Lutz Jaenicke*

 * Fix ssl3_pending() (ssl/s3_lib.c) to prevent SSL_pending() from
   returning non-zero before the data has been completely received
   when using non-blocking I/O.

   *Bodo Moeller; problem pointed out by John Hughes*

 * Some of the ciphers missed the strength entry (SSL_LOW etc).

   *Ben Laurie, Lutz Jaenicke*

 * Fix bug in SSL_clear(): bad sessions were not removed (found by
   Yoram Zahavi <YoramZ@gilian.com>).

   *Lutz Jaenicke*

 * Add information about CygWin 1.3 and on, and preserve proper
   configuration for the versions before that.

   *Corinna Vinschen <vinschen@redhat.com> and Richard Levitte*

 * Make removal from session cache (SSL_CTX_remove_session()) more robust:
   check whether we deal with a copy of a session and do not delete from
   the cache in this case. Problem reported by "Izhar Shoshani Levi"
   <izhar@checkpoint.com>.

   *Lutz Jaenicke*

 * Do not store session data into the internal session cache, if it
   is never intended to be looked up (SSL_SESS_CACHE_NO_INTERNAL_LOOKUP
   flag is set). Proposed by Aslam <aslam@funk.com>.

   *Lutz Jaenicke*

 * Have ASN1_BIT_STRING_set_bit() really clear a bit when the requested
   value is 0.

   *Richard Levitte*

 * [In 0.9.6d-engine release:]
   Fix a crashbug and a logic bug in hwcrhk_load_pubkey().

   *Toomas Kiisk <vix@cyber.ee> via Richard Levitte*

 * Add the configuration target linux-s390x.

   *Neale Ferguson <Neale.Ferguson@SoftwareAG-USA.com> via Richard Levitte*

 * The earlier bugfix for the SSL3_ST_SW_HELLO_REQ_C case of
   ssl3_accept (ssl/s3_srvr.c) incorrectly used a local flag
   variable as an indication that a ClientHello message has been
   received.  As the flag value will be lost between multiple
   invocations of ssl3_accept when using non-blocking I/O, the
   function may not be aware that a handshake has actually taken
   place, thus preventing a new session from being added to the
   session cache.

   To avoid this problem, we now set s->new_session to 2 instead of
   using a local variable.

   *Lutz Jaenicke, Bodo Moeller*

 * Bugfix: Return -1 from ssl3_get_server_done (ssl3/s3_clnt.c)
   if the SSL_R_LENGTH_MISMATCH error is detected.

   *Geoff Thorpe, Bodo Moeller*

 * New 'shared_ldflag' column in Configure platform table.

   *Richard Levitte*

 * Fix EVP_CIPHER_mode macro.

   *"Dan S. Camper" <dan@bti.net>*

 * Fix ssl3_read_bytes (ssl/s3_pkt.c): To ignore messages of unknown
   type, we must throw them away by setting rr->length to 0.

   *D P Chang <dpc@qualys.com>*

### Changes between 0.9.6b and 0.9.6c  [21 dec 2001]

 * Fix BN_rand_range bug pointed out by Dominikus Scherkl
   <Dominikus.Scherkl@biodata.com>.  (The previous implementation
   worked incorrectly for those cases where range = `10..._2`  and
   `3*range`  is two bits longer than  range.)

   *Bodo Moeller*

 * Only add signing time to PKCS7 structures if it is not already
   present.

   *Steve Henson*

 * Fix crypto/objects/objects.h: "ld-ce" should be "id-ce",
   OBJ_ld_ce should be OBJ_id_ce.
   Also some ip-pda OIDs in crypto/objects/objects.txt were
   incorrect (cf. RFC 3039).

   *Matt Cooper, Frederic Giudicelli, Bodo Moeller*

 * Release CRYPTO_LOCK_DYNLOCK when CRYPTO_destroy_dynlockid()
   returns early because it has nothing to do.

   *Andy Schneider <andy.schneider@bjss.co.uk>*

 * [In 0.9.6c-engine release:]
   Fix mutex callback return values in crypto/engine/hw_ncipher.c.

   *Andy Schneider <andy.schneider@bjss.co.uk>*

 * [In 0.9.6c-engine release:]
   Add support for Cryptographic Appliance's keyserver technology.
   (Use engine 'keyclient')

   *Cryptographic Appliances and Geoff Thorpe*

 * Add a configuration entry for OS/390 Unix.  The C compiler 'c89'
   is called via tools/c89.sh because arguments have to be
   rearranged (all '-L' options must appear before the first object
   modules).

   *Richard Shapiro <rshapiro@abinitio.com>*

 * [In 0.9.6c-engine release:]
   Add support for Broadcom crypto accelerator cards, backported
   from 0.9.7.

   *Broadcom, Nalin Dahyabhai <nalin@redhat.com>, Mark Cox*

 * [In 0.9.6c-engine release:]
   Add support for SureWare crypto accelerator cards from
   Baltimore Technologies.  (Use engine 'sureware')

   *Baltimore Technologies and Mark Cox*

 * [In 0.9.6c-engine release:]
   Add support for crypto accelerator cards from Accelerated
   Encryption Processing, www.aep.ie.  (Use engine 'aep')

   *AEP Inc. and Mark Cox*

 * Add a configuration entry for gcc on UnixWare.

   *Gary Benson <gbenson@redhat.com>*

 * Change ssl/s2_clnt.c and ssl/s2_srvr.c so that received handshake
   messages are stored in a single piece (fixed-length part and
   variable-length part combined) and fix various bugs found on the way.

   *Bodo Moeller*

 * Disable caching in BIO_gethostbyname(), directly use gethostbyname()
   instead.  BIO_gethostbyname() does not know what timeouts are
   appropriate, so entries would stay in cache even when they have
   become invalid.
   *Bodo Moeller; problem pointed out by Rich Salz <rsalz@zolera.com>*

 * Change ssl23_get_client_hello (ssl/s23_srvr.c) behaviour when
   faced with a pathologically small ClientHello fragment that does
   not contain client_version: Instead of aborting with an error,
   simply choose the highest available protocol version (i.e.,
   TLS 1.0 unless it is disabled).  In practice, ClientHello
   messages are never sent like this, but this change gives us
   strictly correct behaviour at least for TLS.

   *Bodo Moeller*

 * Fix SSL handshake functions and SSL_clear() such that SSL_clear()
   never resets s->method to s->ctx->method when called from within
   one of the SSL handshake functions.

   *Bodo Moeller; problem pointed out by Niko Baric*

 * In ssl3_get_client_hello (ssl/s3_srvr.c), generate a fatal alert
   (sent using the client's version number) if client_version is
   smaller than the protocol version in use.  Also change
   ssl23_get_client_hello (ssl/s23_srvr.c) to select TLS 1.0 if
   the client demanded SSL 3.0 but only TLS 1.0 is enabled; then
   the client will at least see that alert.

   *Bodo Moeller*

 * Fix ssl3_get_message (ssl/s3_both.c) to handle message fragmentation
   correctly.

   *Bodo Moeller*

 * Avoid infinite loop in ssl3_get_message (ssl/s3_both.c) if a
   client receives HelloRequest while in a handshake.

   *Bodo Moeller; bug noticed by Andy Schneider <andy.schneider@bjss.co.uk>*

 * Bugfix in ssl3_accept (ssl/s3_srvr.c): Case SSL3_ST_SW_HELLO_REQ_C
   should end in 'break', not 'goto end' which circumvents various
   cleanups done in state SSL_ST_OK.   But session related stuff
   must be disabled for SSL_ST_OK in the case that we just sent a
   HelloRequest.

   Also avoid some overhead by not calling ssl_init_wbio_buffer()
   before just sending a HelloRequest.

   *Bodo Moeller, Eric Rescorla <ekr@rtfm.com>*

 * Fix ssl/s3_enc.c, ssl/t1_enc.c and ssl/s3_pkt.c so that we don't
   reveal whether illegal block cipher padding was found or a MAC
   verification error occurred.  (Neither SSLerr() codes nor alerts
   are directly visible to potential attackers, but the information
   may leak via logfiles.)

   Similar changes are not required for the SSL 2.0 implementation
   because the number of padding bytes is sent in clear for SSL 2.0,
   and the extra bytes are just ignored.  However ssl/s2_pkt.c
   failed to verify that the purported number of padding bytes is in
   the legal range.

   *Bodo Moeller*

 * Add OpenUNIX-8 support including shared libraries
   (Boyd Lynn Gerber <gerberb@zenez.com>).

   *Lutz Jaenicke*

 * Improve RSA_padding_check_PKCS1_OAEP() check again to avoid
   'wristwatch attack' using huge encoding parameters (cf.
   James H. Manger's CRYPTO 2001 paper).  Note that the
   RSA_PKCS1_OAEP_PADDING case of RSA_private_decrypt() does not use
   encoding parameters and hence was not vulnerable.

   *Bodo Moeller*

 * BN_sqr() bug fix.

   *Ulf Möller, reported by Jim Ellis <jim.ellis@cavium.com>*

 * Rabin-Miller test analyses assume uniformly distributed witnesses,
   so use BN_pseudo_rand_range() instead of using BN_pseudo_rand()
   followed by modular reduction.

   *Bodo Moeller; pointed out by Adam Young <AYoung1@NCSUS.JNJ.COM>*

 * Add BN_pseudo_rand_range() with obvious functionality: BN_rand_range()
   equivalent based on BN_pseudo_rand() instead of BN_rand().

   *Bodo Moeller*

 * s3_srvr.c: allow sending of large client certificate lists (> 16 kB).
   This function was broken, as the check for a new client hello message
   to handle SGC did not allow these large messages.
   (Tracked down by "Douglas E. Engert" <deengert@anl.gov>.)

   *Lutz Jaenicke*

 * Add alert descriptions for TLSv1 to `SSL_alert_desc_string[_long]()`.

   *Lutz Jaenicke*

 * Fix buggy behaviour of BIO_get_num_renegotiates() and BIO_ctrl()
   for BIO_C_GET_WRITE_BUF_SIZE ("Stephen Hinton" <shinton@netopia.com>).

   *Lutz Jaenicke*

 * Rework the configuration and shared library support for Tru64 Unix.
   The configuration part makes use of modern compiler features and
   still retains old compiler behavior for those that run older versions
   of the OS.  The shared library support part includes a variant that
   uses the RPATH feature, and is available through the special
   configuration target "alpha-cc-rpath", which will never be selected
   automatically.

   *Tim Mooney <mooney@dogbert.cc.ndsu.NoDak.edu> via Richard Levitte*

 * In ssl3_get_key_exchange (ssl/s3_clnt.c), call ssl3_get_message()
   with the same message size as in ssl3_get_certificate_request().
   Otherwise, if no ServerKeyExchange message occurs, CertificateRequest
   messages might inadvertently be reject as too long.

   *Petr Lampa <lampa@fee.vutbr.cz>*

 * Enhanced support for IA-64 Unix platforms (well, Linux and HP-UX).

   *Andy Polyakov*

 * Modified SSL library such that the verify_callback that has been set
   specifically for an SSL object with SSL_set_verify() is actually being
   used. Before the change, a verify_callback set with this function was
   ignored and the verify_callback() set in the SSL_CTX at the time of
   the call was used. New function X509_STORE_CTX_set_verify_cb() introduced
   to allow the necessary settings.

   *Lutz Jaenicke*

 * Initialize static variable in crypto/dsa/dsa_lib.c and crypto/dh/dh_lib.c
   explicitly to NULL, as at least on Solaris 8 this seems not always to be
   done automatically (in contradiction to the requirements of the C
   standard). This made problems when used from OpenSSH.

   *Lutz Jaenicke*

 * In OpenSSL 0.9.6a and 0.9.6b, crypto/dh/dh_key.c ignored
   dh->length and always used

           BN_rand_range(priv_key, dh->p).

   BN_rand_range() is not necessary for Diffie-Hellman, and this
   specific range makes Diffie-Hellman unnecessarily inefficient if
   dh->length (recommended exponent length) is much smaller than the
   length of dh->p.  We could use BN_rand_range() if the order of
   the subgroup was stored in the DH structure, but we only have
   dh->length.

   So switch back to

           BN_rand(priv_key, l, ...)

   where 'l' is dh->length if this is defined, or BN_num_bits(dh->p)-1
   otherwise.

   *Bodo Moeller*

 * In

           RSA_eay_public_encrypt
           RSA_eay_private_decrypt
           RSA_eay_private_encrypt (signing)
           RSA_eay_public_decrypt (signature verification)

   (default implementations for RSA_public_encrypt,
   RSA_private_decrypt, RSA_private_encrypt, RSA_public_decrypt),
   always reject numbers >= n.

   *Bodo Moeller*

 * In crypto/rand/md_rand.c, use a new short-time lock CRYPTO_LOCK_RAND2
   to synchronize access to 'locking_thread'.  This is necessary on
   systems where access to 'locking_thread' (an 'unsigned long'
   variable) is not atomic.

   *Bodo Moeller*

 * In crypto/rand/md_rand.c, set 'locking_thread' to current thread's ID
   *before* setting the 'crypto_lock_rand' flag.  The previous code had
   a race condition if 0 is a valid thread ID.

   *Travis Vitek <vitek@roguewave.com>*

 * Add support for shared libraries under Irix.

   *Albert Chin-A-Young <china@thewrittenword.com>*

 * Add configuration option to build on Linux on both big-endian and
   little-endian MIPS.

   *Ralf Baechle <ralf@uni-koblenz.de>*

 * Add the possibility to create shared libraries on HP-UX.

   *Richard Levitte*

### Changes between 0.9.6a and 0.9.6b  [9 Jul 2001]

 * Change ssleay_rand_bytes (crypto/rand/md_rand.c)
   to avoid a SSLeay/OpenSSL PRNG weakness pointed out by
   Markku-Juhani O. Saarinen <markku-juhani.saarinen@nokia.com>:
   PRNG state recovery was possible based on the output of
   one PRNG request appropriately sized to gain knowledge on
   'md' followed by enough consecutive 1-byte PRNG requests
   to traverse all of 'state'.

   1. When updating 'md_local' (the current thread's copy of 'md')
      during PRNG output generation, hash all of the previous
      'md_local' value, not just the half used for PRNG output.

   2. Make the number of bytes from 'state' included into the hash
      independent from the number of PRNG bytes requested.

   The first measure alone would be sufficient to avoid
   Markku-Juhani's attack.  (Actually it had never occurred
   to me that the half of 'md_local' used for chaining was the
   half from which PRNG output bytes were taken -- I had always
   assumed that the secret half would be used.)  The second
   measure makes sure that additional data from 'state' is never
   mixed into 'md_local' in small portions; this heuristically
   further strengthens the PRNG.

   *Bodo Moeller*

 * Fix crypto/bn/asm/mips3.s.

   *Andy Polyakov*

 * When only the key is given to "enc", the IV is undefined. Print out
   an error message in this case.

   *Lutz Jaenicke*

 * Handle special case when X509_NAME is empty in X509 printing routines.

   *Steve Henson*

 * In dsa_do_verify (crypto/dsa/dsa_ossl.c), verify that r and s are
   positive and less than q.

   *Bodo Moeller*

 * Don't change `*pointer` in CRYPTO_add_lock() is add_lock_callback is
   used: it isn't thread safe and the add_lock_callback should handle
   that itself.

   *Paul Rose <Paul.Rose@bridge.com>*

 * Verify that incoming data obeys the block size in
   ssl3_enc (ssl/s3_enc.c) and tls1_enc (ssl/t1_enc.c).

   *Bodo Moeller*

 * Fix OAEP check.

   *Ulf Möller, Bodo Möller*

 * The countermeasure against Bleichbacher's attack on PKCS #1 v1.5
   RSA encryption was accidentally removed in s3_srvr.c in OpenSSL 0.9.5
   when fixing the server behaviour for backwards-compatible 'client
   hello' messages.  (Note that the attack is impractical against
   SSL 3.0 and TLS 1.0 anyway because length and version checking
   means that the probability of guessing a valid ciphertext is
   around 2^-40; see section 5 in Bleichenbacher's CRYPTO '98
   paper.)

   Before 0.9.5, the countermeasure (hide the error by generating a
   random 'decryption result') did not work properly because
   ERR_clear_error() was missing, meaning that SSL_get_error() would
   detect the supposedly ignored error.

   Both problems are now fixed.

   *Bodo Moeller*

 * In crypto/bio/bf_buff.c, increase DEFAULT_BUFFER_SIZE to 4096
   (previously it was 1024).

   *Bodo Moeller*

 * Fix for compatibility mode trust settings: ignore trust settings
   unless some valid trust or reject settings are present.

   *Steve Henson*

 * Fix for blowfish EVP: its a variable length cipher.

   *Steve Henson*

 * Fix various bugs related to DSA S/MIME verification. Handle missing
   parameters in DSA public key structures and return an error in the
   DSA routines if parameters are absent.

   *Steve Henson*

 * In versions up to 0.9.6, RAND_file_name() resorted to file ".rnd"
   in the current directory if neither $RANDFILE nor $HOME was set.
   RAND_file_name() in 0.9.6a returned NULL in this case.  This has
   caused some confusion to Windows users who haven't defined $HOME.
   Thus RAND_file_name() is changed again: e_os.h can define a
   DEFAULT_HOME, which will be used if $HOME is not set.
   For Windows, we use "C:"; on other platforms, we still require
   environment variables.

 * Move 'if (!initialized) RAND_poll()' into regions protected by
   CRYPTO_LOCK_RAND.  This is not strictly necessary, but avoids
   having multiple threads call RAND_poll() concurrently.

   *Bodo Moeller*

 * In crypto/rand/md_rand.c, replace 'add_do_not_lock' flag by a
   combination of a flag and a thread ID variable.
   Otherwise while one thread is in ssleay_rand_bytes (which sets the
   flag), *other* threads can enter ssleay_add_bytes without obeying
   the CRYPTO_LOCK_RAND lock (and may even illegally release the lock
   that they do not hold after the first thread unsets add_do_not_lock).

   *Bodo Moeller*

 * Change bctest again: '-x' expressions are not available in all
   versions of 'test'.

   *Bodo Moeller*

### Changes between 0.9.6 and 0.9.6a  [5 Apr 2001]

 * Fix a couple of memory leaks in PKCS7_dataDecode()

   *Steve Henson, reported by Heyun Zheng <hzheng@atdsprint.com>*

 * Change Configure and Makefiles to provide EXE_EXT, which will contain
   the default extension for executables, if any.  Also, make the perl
   scripts that use symlink() to test if it really exists and use "cp"
   if it doesn't.  All this made OpenSSL compilable and installable in
   CygWin.

   *Richard Levitte*

 * Fix for asn1_GetSequence() for indefinite length constructed data.
   If SEQUENCE is length is indefinite just set c->slen to the total
   amount of data available.

   *Steve Henson, reported by shige@FreeBSD.org*

   *This change does not apply to 0.9.7.*

 * Change bctest to avoid here-documents inside command substitution
   (workaround for FreeBSD /bin/sh bug).
   For compatibility with Ultrix, avoid shell functions (introduced
   in the bctest version that searches along $PATH).

   *Bodo Moeller*

 * Rename 'des_encrypt' to 'des_encrypt1'.  This avoids the clashes
   with des_encrypt() defined on some operating systems, like Solaris
   and UnixWare.

   *Richard Levitte*

 * Check the result of RSA-CRT (see D. Boneh, R. DeMillo, R. Lipton:
   On the Importance of Eliminating Errors in Cryptographic
   Computations, J. Cryptology 14 (2001) 2, 101-119,
   <http://theory.stanford.edu/~dabo/papers/faults.ps.gz>).

   *Ulf Moeller*

 * MIPS assembler BIGNUM division bug fix.

   *Andy Polyakov*

 * Disabled incorrect Alpha assembler code.

   *Richard Levitte*

 * Fix PKCS#7 decode routines so they correctly update the length
   after reading an EOC for the EXPLICIT tag.

   *Steve Henson*

   *This change does not apply to 0.9.7.*

 * Fix bug in PKCS#12 key generation routines. This was triggered
   if a 3DES key was generated with a 0 initial byte. Include
   PKCS12_BROKEN_KEYGEN compilation option to retain the old
   (but broken) behaviour.

   *Steve Henson*

 * Enhance bctest to search for a working bc along $PATH and print
   it when found.

   *Tim Rice <tim@multitalents.net> via Richard Levitte*

 * Fix memory leaks in err.c: free err_data string if necessary;
   don't write to the wrong index in ERR_set_error_data.

   *Bodo Moeller*

 * Implement ssl23_peek (analogous to ssl23_read), which previously
   did not exist.

   *Bodo Moeller*

 * Replace rdtsc with `_emit` statements for VC++ version 5.

   *Jeremy Cooper <jeremy@baymoo.org>*

 * Make it possible to reuse SSLv2 sessions.

   *Richard Levitte*

 * In copy_email() check for >= 0 as a return value for
   X509_NAME_get_index_by_NID() since 0 is a valid index.

   *Steve Henson reported by Massimiliano Pala <madwolf@opensca.org>*

 * Avoid coredump with unsupported or invalid public keys by checking if
   X509_get_pubkey() fails in PKCS7_verify(). Fix memory leak when
   PKCS7_verify() fails with non detached data.

   *Steve Henson*

 * Don't use getenv in library functions when run as setuid/setgid.
   New function OPENSSL_issetugid().

   *Ulf Moeller*

 * Avoid false positives in memory leak detection code (crypto/mem_dbg.c)
   due to incorrect handling of multi-threading:

   1. Fix timing glitch in the MemCheck_off() portion of CRYPTO_mem_ctrl().

   2. Fix logical glitch in is_MemCheck_on() aka CRYPTO_is_mem_check_on().

   3. Count how many times MemCheck_off() has been called so that
      nested use can be treated correctly.  This also avoids
      inband-signalling in the previous code (which relied on the
      assumption that thread ID 0 is impossible).

   *Bodo Moeller*

 * Add "-rand" option also to s_client and s_server.

   *Lutz Jaenicke*

 * Fix CPU detection on Irix 6.x.
   *Kurt Hockenbury <khockenb@stevens-tech.edu> and
   "Bruce W. Forsberg" <bruce.forsberg@baesystems.com>*

 * Fix X509_NAME bug which produced incorrect encoding if X509_NAME
   was empty.

   *Steve Henson*

   *This change does not apply to 0.9.7.*

 * Use the cached encoding of an X509_NAME structure rather than
   copying it. This is apparently the reason for the libsafe "errors"
   but the code is actually correct.

   *Steve Henson*

 * Add new function BN_rand_range(), and fix DSA_sign_setup() to prevent
   Bleichenbacher's DSA attack.
   Extend BN_[pseudo_]rand: As before, top=1 forces the highest two bits
   to be set and top=0 forces the highest bit to be set; top=-1 is new
   and leaves the highest bit random.

   *Ulf Moeller, Bodo Moeller*

 * In the `NCONF_...`-based implementations for `CONF_...` queries
   (crypto/conf/conf_lib.c), if the input LHASH is NULL, avoid using
   a temporary CONF structure with the data component set to NULL
   (which gives segmentation faults in lh_retrieve).
   Instead, use NULL for the CONF pointer in CONF_get_string and
   CONF_get_number (which may use environment variables) and directly
   return NULL from CONF_get_section.

   *Bodo Moeller*

 * Fix potential buffer overrun for EBCDIC.

   *Ulf Moeller*

 * Tolerate nonRepudiation as being valid for S/MIME signing and certSign
   keyUsage if basicConstraints absent for a CA.

   *Steve Henson*

 * Make SMIME_write_PKCS7() write mail header values with a format that
   is more generally accepted (no spaces before the semicolon), since
   some programs can't parse those values properly otherwise.  Also make
   sure BIO's that break lines after each write do not create invalid
   headers.

   *Richard Levitte*

 * Make the CRL encoding routines work with empty SEQUENCE OF. The
   macros previously used would not encode an empty SEQUENCE OF
   and break the signature.

   *Steve Henson*

   *This change does not apply to 0.9.7.*

 * Zero the premaster secret after deriving the master secret in
   DH ciphersuites.

   *Steve Henson*

 * Add some EVP_add_digest_alias registrations (as found in
   OpenSSL_add_all_digests()) to SSL_library_init()
   aka OpenSSL_add_ssl_algorithms().  This provides improved
   compatibility with peers using X.509 certificates
   with unconventional AlgorithmIdentifier OIDs.

   *Bodo Moeller*

 * Fix for Irix with NO_ASM.

   *"Bruce W. Forsberg" <bruce.forsberg@baesystems.com>*

 * ./config script fixes.

   *Ulf Moeller, Richard Levitte*

 * Fix 'openssl passwd -1'.

   *Bodo Moeller*

 * Change PKCS12_key_gen_asc() so it can cope with non null
   terminated strings whose length is passed in the passlen
   parameter, for example from PEM callbacks. This was done
   by adding an extra length parameter to asc2uni().

   *Steve Henson, reported by <oddissey@samsung.co.kr>*

 * Fix C code generated by 'openssl dsaparam -C': If a BN_bin2bn
   call failed, free the DSA structure.

   *Bodo Moeller*

 * Fix to uni2asc() to cope with zero length Unicode strings.
   These are present in some PKCS#12 files.

   *Steve Henson*

 * Increase s2->wbuf allocation by one byte in ssl2_new (ssl/s2_lib.c).
   Otherwise do_ssl_write (ssl/s2_pkt.c) will write beyond buffer limits
   when writing a 32767 byte record.

   *Bodo Moeller; problem reported by Eric Day <eday@concentric.net>*

 * In `RSA_eay_public_{en,ed}crypt` and RSA_eay_mod_exp (rsa_eay.c),
   obtain lock CRYPTO_LOCK_RSA before setting `rsa->_method_mod_{n,p,q}`.

   (RSA objects have a reference count access to which is protected
   by CRYPTO_LOCK_RSA [see rsa_lib.c, s3_srvr.c, ssl_cert.c, ssl_rsa.c],
   so they are meant to be shared between threads.)
   *Bodo Moeller, Geoff Thorpe; original patch submitted by
   "Reddie, Steven" <Steven.Reddie@ca.com>*

 * Fix a deadlock in CRYPTO_mem_leaks().

   *Bodo Moeller*

 * Use better test patterns in bntest.

   *Ulf Möller*

 * rand_win.c fix for Borland C.

   *Ulf Möller*

 * BN_rshift bugfix for n == 0.

   *Bodo Moeller*

 * Add a 'bctest' script that checks for some known 'bc' bugs
   so that 'make test' does not abort just because 'bc' is broken.

   *Bodo Moeller*

 * Store verify_result within SSL_SESSION also for client side to
   avoid potential security hole. (Re-used sessions on the client side
   always resulted in verify_result==X509_V_OK, not using the original
   result of the server certificate verification.)

   *Lutz Jaenicke*

 * Fix ssl3_pending: If the record in s->s3->rrec is not of type
   SSL3_RT_APPLICATION_DATA, return 0.
   Similarly, change ssl2_pending to return 0 if SSL_in_init(s) is true.

   *Bodo Moeller*

 * Fix SSL_peek:
   Both ssl2_peek and ssl3_peek, which were totally broken in earlier
   releases, have been re-implemented by renaming the previous
   implementations of ssl2_read and ssl3_read to ssl2_read_internal
   and ssl3_read_internal, respectively, and adding 'peek' parameters
   to them.  The new ssl[23]_{read,peek} functions are calls to
   ssl[23]_read_internal with the 'peek' flag set appropriately.
   A 'peek' parameter has also been added to ssl3_read_bytes, which
   does the actual work for ssl3_read_internal.

   *Bodo Moeller*

 * Initialise "ex_data" member of RSA/DSA/DH structures prior to calling
   the method-specific "init()" handler. Also clean up ex_data after
   calling the method-specific "finish()" handler. Previously, this was
   happening the other way round.

   *Geoff Thorpe*

 * Increase BN_CTX_NUM (the number of BIGNUMs in a BN_CTX) to 16.
   The previous value, 12, was not always sufficient for BN_mod_exp().

   *Bodo Moeller*

 * Make sure that shared libraries get the internal name engine with
   the full version number and not just 0.  This should mark the
   shared libraries as not backward compatible.  Of course, this should
   be changed again when we can guarantee backward binary compatibility.

   *Richard Levitte*

 * Fix typo in get_cert_by_subject() in by_dir.c

   *Jean-Marc Desperrier <jean-marc.desperrier@certplus.com>*

 * Rework the system to generate shared libraries:

   - Make note of the expected extension for the shared libraries and
     if there is a need for symbolic links from for example libcrypto.so.0
     to libcrypto.so.0.9.7.  There is extended info in Configure for
     that.

   - Make as few rebuilds of the shared libraries as possible.

   - Still avoid linking the OpenSSL programs with the shared libraries.

   - When installing, install the shared libraries separately from the
     static ones.

   *Richard Levitte*

 * Fix SSL_CTX_set_read_ahead macro to actually use its argument.

   Copy SSL_CTX's read_ahead flag to SSL object directly in SSL_new
   and not in SSL_clear because the latter is also used by the
   accept/connect functions; previously, the settings made by
   SSL_set_read_ahead would be lost during the handshake.

   *Bodo Moeller; problems reported by Anders Gertz <gertz@epact.se>*

 * Correct util/mkdef.pl to be selective about disabled algorithms.
   Previously, it would create entries for disabled algorithms no
   matter what.

   *Richard Levitte*

 * Added several new manual pages for SSL_* function.

   *Lutz Jaenicke*

### Changes between 0.9.5a and 0.9.6  [24 Sep 2000]

 * In ssl23_get_client_hello, generate an error message when faced
   with an initial SSL 3.0/TLS record that is too small to contain the
   first two bytes of the ClientHello message, i.e. client_version.
   (Note that this is a pathologic case that probably has never happened
   in real life.)  The previous approach was to use the version number
   from the record header as a substitute; but our protocol choice
   should not depend on that one because it is not authenticated
   by the Finished messages.

   *Bodo Moeller*

 * More robust randomness gathering functions for Windows.

   *Jeffrey Altman <jaltman@columbia.edu>*

 * For compatibility reasons if the flag X509_V_FLAG_ISSUER_CHECK is
   not set then we don't setup the error code for issuer check errors
   to avoid possibly overwriting other errors which the callback does
   handle. If an application does set the flag then we assume it knows
   what it is doing and can handle the new informational codes
   appropriately.

   *Steve Henson*

 * Fix for a nasty bug in ASN1_TYPE handling. ASN1_TYPE is used for
   a general "ANY" type, as such it should be able to decode anything
   including tagged types. However it didn't check the class so it would
   wrongly interpret tagged types in the same way as their universal
   counterpart and unknown types were just rejected. Changed so that the
   tagged and unknown types are handled in the same way as a SEQUENCE:
   that is the encoding is stored intact. There is also a new type
   "V_ASN1_OTHER" which is used when the class is not universal, in this
   case we have no idea what the actual type is so we just lump them all
   together.

   *Steve Henson*

 * On VMS, stdout may very well lead to a file that is written to
   in a record-oriented fashion.  That means that every write() will
   write a separate record, which will be read separately by the
   programs trying to read from it.  This can be very confusing.

   The solution is to put a BIO filter in the way that will buffer
   text until a linefeed is reached, and then write everything a
   line at a time, so every record written will be an actual line,
   not chunks of lines and not (usually doesn't happen, but I've
   seen it once) several lines in one record.  BIO_f_linebuffer() is
   the answer.

   Currently, it's a VMS-only method, because that's where it has
   been tested well enough.

   *Richard Levitte*

 * Remove 'optimized' squaring variant in BN_mod_mul_montgomery,
   it can return incorrect results.
   (Note: The buggy variant was not enabled in OpenSSL 0.9.5a,
   but it was in 0.9.6-beta[12].)

   *Bodo Moeller*

 * Disable the check for content being present when verifying detached
   signatures in pk7_smime.c. Some versions of Netscape (wrongly)
   include zero length content when signing messages.

   *Steve Henson*

 * New BIO_shutdown_wr macro, which invokes the BIO_C_SHUTDOWN_WR
   BIO_ctrl (for BIO pairs).

   *Bodo Möller*

 * Add DSO method for VMS.

   *Richard Levitte*

 * Bug fix: Montgomery multiplication could produce results with the
   wrong sign.

   *Ulf Möller*

 * Add RPM specification openssl.spec and modify it to build three
   packages.  The default package contains applications, application
   documentation and run-time libraries.  The devel package contains
   include files, static libraries and function documentation.  The
   doc package contains the contents of the doc directory.  The original
   openssl.spec was provided by Damien Miller <djm@mindrot.org>.

   *Richard Levitte*

 * Add a large number of documentation files for many SSL routines.

   *Lutz Jaenicke <Lutz.Jaenicke@aet.TU-Cottbus.DE>*

 * Add a configuration entry for Sony News 4.

   *NAKAJI Hiroyuki <nakaji@tutrp.tut.ac.jp>*

 * Don't set the two most significant bits to one when generating a
   random number < q in the DSA library.

   *Ulf Möller*

 * New SSL API mode 'SSL_MODE_AUTO_RETRY'.  This disables the default
   behaviour that SSL_read may result in SSL_ERROR_WANT_READ (even if
   the underlying transport is blocking) if a handshake took place.
   (The default behaviour is needed by applications such as s_client
   and s_server that use select() to determine when to use SSL_read;
   but for applications that know in advance when to expect data, it
   just makes things more complicated.)

   *Bodo Moeller*

 * Add RAND_egd_bytes(), which gives control over the number of bytes read
   from EGD.

   *Ben Laurie*

 * Add a few more EBCDIC conditionals that make `req` and `x509`
   work better on such systems.

   *Martin Kraemer <Martin.Kraemer@MchP.Siemens.De>*

 * Add two demo programs for PKCS12_parse() and PKCS12_create().
   Update PKCS12_parse() so it copies the friendlyName and the
   keyid to the certificates aux info.

   *Steve Henson*

 * Fix bug in PKCS7_verify() which caused an infinite loop
   if there was more than one signature.

   *Sven Uszpelkat <su@celocom.de>*

 * Major change in util/mkdef.pl to include extra information
   about each symbol, as well as presenting variables as well
   as functions.  This change means that there's n more need
   to rebuild the .num files when some algorithms are excluded.

   *Richard Levitte*

 * Allow the verify time to be set by an application,
   rather than always using the current time.

   *Steve Henson*

 * Phase 2 verify code reorganisation. The certificate
   verify code now looks up an issuer certificate by a
   number of criteria: subject name, authority key id
   and key usage. It also verifies self signed certificates
   by the same criteria. The main comparison function is
   X509_check_issued() which performs these checks.

   Lot of changes were necessary in order to support this
   without completely rewriting the lookup code.

   Authority and subject key identifier are now cached.

   The LHASH 'certs' is X509_STORE has now been replaced
   by a STACK_OF(X509_OBJECT). This is mainly because an
   LHASH can't store or retrieve multiple objects with
   the same hash value.

   As a result various functions (which were all internal
   use only) have changed to handle the new X509_STORE
   structure. This will break anything that messed round
   with X509_STORE internally.

   The functions X509_STORE_add_cert() now checks for an
   exact match, rather than just subject name.

   The X509_STORE API doesn't directly support the retrieval
   of multiple certificates matching a given criteria, however
   this can be worked round by performing a lookup first
   (which will fill the cache with candidate certificates)
   and then examining the cache for matches. This is probably
   the best we can do without throwing out X509_LOOKUP
   entirely (maybe later...).

   The X509_VERIFY_CTX structure has been enhanced considerably.

   All certificate lookup operations now go via a get_issuer()
   callback. Although this currently uses an X509_STORE it
   can be replaced by custom lookups. This is a simple way
   to bypass the X509_STORE hackery necessary to make this
   work and makes it possible to use more efficient techniques
   in future. A very simple version which uses a simple
   STACK for its trusted certificate store is also provided
   using X509_STORE_CTX_trusted_stack().

   The verify_cb() and verify() callbacks now have equivalents
   in the X509_STORE_CTX structure.

   X509_STORE_CTX also has a 'flags' field which can be used
   to customise the verify behaviour.

   *Steve Henson*

 * Add new PKCS#7 signing option PKCS7_NOSMIMECAP which
   excludes S/MIME capabilities.

   *Steve Henson*

 * When a certificate request is read in keep a copy of the
   original encoding of the signed data and use it when outputting
   again. Signatures then use the original encoding rather than
   a decoded, encoded version which may cause problems if the
   request is improperly encoded.

   *Steve Henson*

 * For consistency with other BIO_puts implementations, call
   buffer_write(b, ...) directly in buffer_puts instead of calling
   BIO_write(b, ...).

   In BIO_puts, increment b->num_write as in BIO_write.

   *Peter.Sylvester@EdelWeb.fr*

 * Fix BN_mul_word for the case where the word is 0. (We have to use
   BN_zero, we may not return a BIGNUM with an array consisting of
   words set to zero.)

   *Bodo Moeller*

 * Avoid calling abort() from within the library when problems are
   detected, except if preprocessor symbols have been defined
   (such as REF_CHECK, BN_DEBUG etc.).

   *Bodo Moeller*

 * New openssl application 'rsautl'. This utility can be
   used for low-level RSA operations. DER public key
   BIO/fp routines also added.

   *Steve Henson*

 * New Configure entry and patches for compiling on QNX 4.

   *Andreas Schneider <andreas@ds3.etech.fh-hamburg.de>*

 * A demo state-machine implementation was sponsored by
   Nuron (<http://www.nuron.com/>) and is now available in
   demos/state_machine.

   *Ben Laurie*

 * New options added to the 'dgst' utility for signature
   generation and verification.

   *Steve Henson*

 * Unrecognized PKCS#7 content types are now handled via a
   catch all ASN1_TYPE structure. This allows unsupported
   types to be stored as a "blob" and an application can
   encode and decode it manually.

   *Steve Henson*

 * Fix various signed/unsigned issues to make a_strex.c
   compile under VC++.

   *Oscar Jacobsson <oscar.jacobsson@celocom.com>*

 * ASN1 fixes. i2d_ASN1_OBJECT was not returning the correct
   length if passed a buffer. ASN1_INTEGER_to_BN failed
   if passed a NULL BN and its argument was negative.

   *Steve Henson, pointed out by Sven Heiberg <sven@tartu.cyber.ee>*

 * Modification to PKCS#7 encoding routines to output definite
   length encoding. Since currently the whole structures are in
   memory there's not real point in using indefinite length
   constructed encoding. However if OpenSSL is compiled with
   the flag PKCS7_INDEFINITE_ENCODING the old form is used.

   *Steve Henson*

 * Added BIO_vprintf() and BIO_vsnprintf().

   *Richard Levitte*

 * Added more prefixes to parse for in the strings written
   through a logging bio, to cover all the levels that are available
   through syslog.  The prefixes are now:

           PANIC, EMERG, EMR       =>      LOG_EMERG
           ALERT, ALR              =>      LOG_ALERT
           CRIT, CRI               =>      LOG_CRIT
           ERROR, ERR              =>      LOG_ERR
           WARNING, WARN, WAR      =>      LOG_WARNING
           NOTICE, NOTE, NOT       =>      LOG_NOTICE
           INFO, INF               =>      LOG_INFO
           DEBUG, DBG              =>      LOG_DEBUG

   and as before, if none of those prefixes are present at the
   beginning of the string, LOG_ERR is chosen.

   On Win32, the `LOG_*` levels are mapped according to this:

           LOG_EMERG, LOG_ALERT, LOG_CRIT, LOG_ERR => EVENTLOG_ERROR_TYPE
           LOG_WARNING                             => EVENTLOG_WARNING_TYPE
           LOG_NOTICE, LOG_INFO, LOG_DEBUG         => EVENTLOG_INFORMATION_TYPE

   *Richard Levitte*

 * Made it possible to reconfigure with just the configuration
   argument "reconf" or "reconfigure".  The command line arguments
   are stored in Makefile.ssl in the variable CONFIGURE_ARGS,
   and are retrieved from there when reconfiguring.

   *Richard Levitte*

 * MD4 implemented.

   *Assar Westerlund <assar@sics.se>, Richard Levitte*

 * Add the arguments -CAfile and -CApath to the pkcs12 utility.

   *Richard Levitte*

 * The obj_dat.pl script was messing up the sorting of object
   names. The reason was that it compared the quoted version
   of strings as a result "OCSP" > "OCSP Signing" because
   " > SPACE. Changed script to store unquoted versions of
   names and add quotes on output. It was also omitting some
   names from the lookup table if they were given a default
   value (that is if SN is missing it is given the same
   value as LN and vice versa), these are now added on the
   grounds that if an object has a name we should be able to
   look it up. Finally added warning output when duplicate
   short or long names are found.

   *Steve Henson*

 * Changes needed for Tandem NSK.

   *Scott Uroff <scott@xypro.com>*

 * Fix SSL 2.0 rollback checking: Due to an off-by-one error in
   RSA_padding_check_SSLv23(), special padding was never detected
   and thus the SSL 3.0/TLS 1.0 countermeasure against protocol
   version rollback attacks was not effective.

   In s23_clnt.c, don't use special rollback-attack detection padding
   (RSA_SSLV23_PADDING) if SSL 2.0 is the only protocol enabled in the
   client; similarly, in s23_srvr.c, don't do the rollback check if
   SSL 2.0 is the only protocol enabled in the server.

   *Bodo Moeller*

 * Make it possible to get hexdumps of unprintable data with 'openssl
   asn1parse'.  By implication, the functions ASN1_parse_dump() and
   BIO_dump_indent() are added.

   *Richard Levitte*

 * New functions ASN1_STRING_print_ex() and X509_NAME_print_ex()
   these print out strings and name structures based on various
   flags including RFC2253 support and proper handling of
   multibyte characters. Added options to the 'x509' utility
   to allow the various flags to be set.

   *Steve Henson*

 * Various fixes to use ASN1_TIME instead of ASN1_UTCTIME.
   Also change the functions X509_cmp_current_time() and
   X509_gmtime_adj() work with an ASN1_TIME structure,
   this will enable certificates using GeneralizedTime in validity
   dates to be checked.

   *Steve Henson*

 * Make the NEG_PUBKEY_BUG code (which tolerates invalid
   negative public key encodings) on by default,
   NO_NEG_PUBKEY_BUG can be set to disable it.

   *Steve Henson*

 * New function c2i_ASN1_OBJECT() which acts on ASN1_OBJECT
   content octets. An i2c_ASN1_OBJECT is unnecessary because
   the encoding can be trivially obtained from the structure.

   *Steve Henson*

 * crypto/err.c locking bugfix: Use write locks (`CRYPTO_w_[un]lock`),
   not read locks (`CRYPTO_r_[un]lock`).

   *Bodo Moeller*

 * A first attempt at creating official support for shared
   libraries through configuration.  I've kept it so the
   default is static libraries only, and the OpenSSL programs
   are always statically linked for now, but there are
   preparations for dynamic linking in place.
   This has been tested on Linux and Tru64.

   *Richard Levitte*

 * Randomness polling function for Win9x, as described in:
   Peter Gutmann, Software Generation of Practically Strong
   Random Numbers.

   *Ulf Möller*

 * Fix so PRNG is seeded in req if using an already existing
   DSA key.

   *Steve Henson*

 * New options to smime application. -inform and -outform
   allow alternative formats for the S/MIME message including
   PEM and DER. The -content option allows the content to be
   specified separately. This should allow things like Netscape
   form signing output easier to verify.

   *Steve Henson*

 * Fix the ASN1 encoding of tags using the 'long form'.

   *Steve Henson*

 * New ASN1 functions, `i2c_*` and `c2i_*` for INTEGER and BIT
   STRING types. These convert content octets to and from the
   underlying type. The actual tag and length octets are
   already assumed to have been read in and checked. These
   are needed because all other string types have virtually
   identical handling apart from the tag. By having versions
   of the ASN1 functions that just operate on content octets
   IMPLICIT tagging can be handled properly. It also allows
   the ASN1_ENUMERATED code to be cut down because ASN1_ENUMERATED
   and ASN1_INTEGER are identical apart from the tag.

   *Steve Henson*

 * Change the handling of OID objects as follows:

   - New object identifiers are inserted in objects.txt, following
     the syntax given in [crypto/objects/README.md](crypto/objects/README.md).
   - objects.pl is used to process obj_mac.num and create a new
     obj_mac.h.
   - obj_dat.pl is used to create a new obj_dat.h, using the data in
     obj_mac.h.

   This is currently kind of a hack, and the perl code in objects.pl
   isn't very elegant, but it works as I intended.  The simplest way
   to check that it worked correctly is to look in obj_dat.h and
   check the array nid_objs and make sure the objects haven't moved
   around (this is important!).  Additions are OK, as well as
   consistent name changes.

   *Richard Levitte*

 * Add BSD-style MD5-based passwords to 'openssl passwd' (option '-1').

   *Bodo Moeller*

 * Addition of the command line parameter '-rand file' to 'openssl req'.
   The given file adds to whatever has already been seeded into the
   random pool through the RANDFILE configuration file option or
   environment variable, or the default random state file.

   *Richard Levitte*

 * mkstack.pl now sorts each macro group into lexical order.
   Previously the output order depended on the order the files
   appeared in the directory, resulting in needless rewriting
   of safestack.h .

   *Steve Henson*

 * Patches to make OpenSSL compile under Win32 again. Mostly
   work arounds for the VC++ problem that it treats func() as
   func(void). Also stripped out the parts of mkdef.pl that
   added extra typesafe functions: these no longer exist.

   *Steve Henson*

 * Reorganisation of the stack code. The macros are now all
   collected in safestack.h . Each macro is defined in terms of
   a "stack macro" of the form `SKM_<name>(type, a, b)`. The
   DEBUG_SAFESTACK is now handled in terms of function casts,
   this has the advantage of retaining type safety without the
   use of additional functions. If DEBUG_SAFESTACK is not defined
   then the non typesafe macros are used instead. Also modified the
   mkstack.pl script to handle the new form. Needs testing to see
   if which (if any) compilers it chokes and maybe make DEBUG_SAFESTACK
   the default if no major problems. Similar behaviour for ASN1_SET_OF
   and PKCS12_STACK_OF.

   *Steve Henson*

 * When some versions of IIS use the 'NET' form of private key the
   key derivation algorithm is different. Normally MD5(password) is
   used as a 128 bit RC4 key. In the modified case
   MD5(MD5(password) + "SGCKEYSALT")  is used instead. Added some
   new functions i2d_RSA_NET(), d2i_RSA_NET() etc which are the same
   as the old Netscape_RSA functions except they have an additional
   'sgckey' parameter which uses the modified algorithm. Also added
   an -sgckey command line option to the rsa utility. Thanks to
   Adrian Peck <bertie@ncipher.com> for posting details of the modified
   algorithm to openssl-dev.

   *Steve Henson*

 * The evp_local.h macros were using 'c.##kname' which resulted in
   invalid expansion on some systems (SCO 5.0.5 for example).
   Corrected to 'c.kname'.

   *Phillip Porch <root@theporch.com>*

 * New X509_get1_email() and X509_REQ_get1_email() functions that return
   a STACK of email addresses from a certificate or request, these look
   in the subject name and the subject alternative name extensions and
   omit any duplicate addresses.

   *Steve Henson*

 * Re-implement BN_mod_exp2_mont using independent (and larger) windows.
   This makes DSA verification about 2 % faster.

   *Bodo Moeller*

 * Increase maximum window size in `BN_mod_exp_...` to 6 bits instead of 5
   (meaning that now 2^5 values will be precomputed, which is only 4 KB
   plus overhead for 1024 bit moduli).
   This makes exponentiations about 0.5 % faster for 1024 bit
   exponents (as measured by "openssl speed rsa2048").

   *Bodo Moeller*

 * Rename memory handling macros to avoid conflicts with other
   software:
           Malloc         =>  OPENSSL_malloc
           Malloc_locked  =>  OPENSSL_malloc_locked
           Realloc        =>  OPENSSL_realloc
           Free           =>  OPENSSL_free

   *Richard Levitte*

 * New function BN_mod_exp_mont_word for small bases (roughly 15%
   faster than BN_mod_exp_mont, i.e. 7% for a full DH exchange).

   *Bodo Moeller*

 * CygWin32 support.

   *John Jarvie <jjarvie@newsguy.com>*

 * The type-safe stack code has been rejigged. It is now only compiled
   in when OpenSSL is configured with the DEBUG_SAFESTACK option and
   by default all type-specific stack functions are "#define"d back to
   standard stack functions. This results in more streamlined output
   but retains the type-safety checking possibilities of the original
   approach.

   *Geoff Thorpe*

 * The STACK code has been cleaned up, and certain type declarations
   that didn't make a lot of sense have been brought in line. This has
   also involved a cleanup of sorts in safestack.h to more correctly
   map type-safe stack functions onto their plain stack counterparts.
   This work has also resulted in a variety of "const"ifications of
   lots of the code, especially `_cmp` operations which should normally
   be prototyped with "const" parameters anyway.

   *Geoff Thorpe*

 * When generating bytes for the first time in md_rand.c, 'stir the pool'
   by seeding with STATE_SIZE dummy bytes (with zero entropy count).
   (The PRNG state consists of two parts, the large pool 'state' and 'md',
   where all of 'md' is used each time the PRNG is used, but 'state'
   is used only indexed by a cyclic counter. As entropy may not be
   well distributed from the beginning, 'md' is important as a
   chaining variable. However, the output function chains only half
   of 'md', i.e. 80 bits.  ssleay_rand_add, on the other hand, chains
   all of 'md', and seeding with STATE_SIZE dummy bytes will result
   in all of 'state' being rewritten, with the new values depending
   on virtually all of 'md'.  This overcomes the 80 bit limitation.)

   *Bodo Moeller*

 * In ssl/s2_clnt.c and ssl/s3_clnt.c, call ERR_clear_error() when
   the handshake is continued after ssl_verify_cert_chain();
   otherwise, if SSL_VERIFY_NONE is set, remaining error codes
   can lead to 'unexplainable' connection aborts later.

   *Bodo Moeller; problem tracked down by Lutz Jaenicke*

 * Major EVP API cipher revision.
   Add hooks for extra EVP features. This allows various cipher
   parameters to be set in the EVP interface. Support added for variable
   key length ciphers via the EVP_CIPHER_CTX_set_key_length() function and
   setting of RC2 and RC5 parameters.

   Modify EVP_OpenInit() and EVP_SealInit() to cope with variable key length
   ciphers.

   Remove lots of duplicated code from the EVP library. For example *every*
   cipher init() function handles the 'iv' in the same way according to the
   cipher mode. They also all do nothing if the 'key' parameter is NULL and
   for CFB and OFB modes they zero ctx->num.

   New functionality allows removal of S/MIME code RC2 hack.

   Most of the routines have the same form and so can be declared in terms
   of macros.

   By shifting this to the top level EVP_CipherInit() it can be removed from
   all individual ciphers. If the cipher wants to handle IVs or keys
   differently it can set the EVP_CIPH_CUSTOM_IV or EVP_CIPH_ALWAYS_CALL_INIT
   flags.

   Change lots of functions like EVP_EncryptUpdate() to now return a
   value: although software versions of the algorithms cannot fail
   any installed hardware versions can.

   *Steve Henson*

 * Implement SSL_OP_TLS_ROLLBACK_BUG: In ssl3_get_client_key_exchange, if
   this option is set, tolerate broken clients that send the negotiated
   protocol version number instead of the requested protocol version
   number.

   *Bodo Moeller*

 * Call dh_tmp_cb (set by `..._TMP_DH_CB`) with correct 'is_export' flag;
   i.e. non-zero for export ciphersuites, zero otherwise.
   Previous versions had this flag inverted, inconsistent with
   rsa_tmp_cb (..._TMP_RSA_CB).

   *Bodo Moeller; problem reported by Amit Chopra*

 * Add missing DSA library text string. Work around for some IIS
   key files with invalid SEQUENCE encoding.

   *Steve Henson*

 * Add a document (doc/standards.txt) that list all kinds of standards
   and so on that are implemented in OpenSSL.

   *Richard Levitte*

 * Enhance c_rehash script. Old version would mishandle certificates
   with the same subject name hash and wouldn't handle CRLs at all.
   Added -fingerprint option to crl utility, to support new c_rehash
   features.

   *Steve Henson*

 * Eliminate non-ANSI declarations in crypto.h and stack.h.

   *Ulf Möller*

 * Fix for SSL server purpose checking. Server checking was
   rejecting certificates which had extended key usage present
   but no ssl client purpose.

   *Steve Henson, reported by Rene Grosser <grosser@hisolutions.com>*

 * Make PKCS#12 code work with no password. The PKCS#12 spec
   is a little unclear about how a blank password is handled.
   Since the password in encoded as a BMPString with terminating
   double NULL a zero length password would end up as just the
   double NULL. However no password at all is different and is
   handled differently in the PKCS#12 key generation code. NS
   treats a blank password as zero length. MSIE treats it as no
   password on export: but it will try both on import. We now do
   the same: PKCS12_parse() tries zero length and no password if
   the password is set to "" or NULL (NULL is now a valid password:
   it wasn't before) as does the pkcs12 application.

   *Steve Henson*

 * Bugfixes in `apps/x509.c`: Avoid a memory leak; and don't use
   perror when PEM_read_bio_X509_REQ fails, the error message must
   be obtained from the error queue.

   *Bodo Moeller*

 * Avoid 'thread_hash' memory leak in crypto/err/err.c by freeing
   it in ERR_remove_state if appropriate, and change ERR_get_state
   accordingly to avoid race conditions (this is necessary because
   thread_hash is no longer constant once set).

   *Bodo Moeller*

 * Bugfix for linux-elf makefile.one.

   *Ulf Möller*

 * RSA_get_default_method() will now cause a default
   RSA_METHOD to be chosen if one doesn't exist already.
   Previously this was only set during a call to RSA_new()
   or RSA_new_method(NULL) meaning it was possible for
   RSA_get_default_method() to return NULL.

   *Geoff Thorpe*

 * Added native name translation to the existing DSO code
   that will convert (if the flag to do so is set) filenames
   that are sufficiently small and have no path information
   into a canonical native form. Eg. "blah" converted to
   "libblah.so" or "blah.dll" etc.

   *Geoff Thorpe*

 * New function ERR_error_string_n(e, buf, len) which is like
   ERR_error_string(e, buf), but writes at most 'len' bytes
   including the 0 terminator.  For ERR_error_string_n, 'buf'
   may not be NULL.

   *Damien Miller <djm@mindrot.org>, Bodo Moeller*

 * CONF library reworked to become more general.  A new CONF
   configuration file reader "class" is implemented as well as a
   new functions (`NCONF_*`, for "New CONF") to handle it.  The now
   old `CONF_*` functions are still there, but are reimplemented to
   work in terms of the new functions.  Also, a set of functions
   to handle the internal storage of the configuration data is
   provided to make it easier to write new configuration file
   reader "classes" (I can definitely see something reading a
   configuration file in XML format, for example), called `_CONF_*`,
   or "the configuration storage API"...

   The new configuration file reading functions are:

           NCONF_new, NCONF_free, NCONF_load, NCONF_load_fp, NCONF_load_bio,
           NCONF_get_section, NCONF_get_string, NCONF_get_numbre

           NCONF_default, NCONF_WIN32

           NCONF_dump_fp, NCONF_dump_bio

   NCONF_default and NCONF_WIN32 are method (or "class") choosers,
   NCONF_new creates a new CONF object.  This works in the same way
   as other interfaces in OpenSSL, like the BIO interface.
   `NCONF_dump_*` dump the internal storage of the configuration file,
   which is useful for debugging.  All other functions take the same
   arguments as the old `CONF_*` functions with the exception of the
   first that must be a `CONF *` instead of a `LHASH *`.

   To make it easier to use the new classes with the old `CONF_*` functions,
   the function CONF_set_default_method is provided.

   *Richard Levitte*

 * Add '-tls1' option to 'openssl ciphers', which was already
   mentioned in the documentation but had not been implemented.
   (This option is not yet really useful because even the additional
   experimental TLS 1.0 ciphers are currently treated as SSL 3.0 ciphers.)

   *Bodo Moeller*

 * Initial DSO code added into libcrypto for letting OpenSSL (and
   OpenSSL-based applications) load shared libraries and bind to
   them in a portable way.

   *Geoff Thorpe, with contributions from Richard Levitte*

### Changes between 0.9.5 and 0.9.5a  [1 Apr 2000]

 * Make sure _lrotl and _lrotr are only used with MSVC.

 * Use lock CRYPTO_LOCK_RAND correctly in ssleay_rand_status
   (the default implementation of RAND_status).

 * Rename openssl x509 option '-crlext', which was added in 0.9.5,
   to '-clrext' (= clear extensions), as intended and documented.
   *Bodo Moeller; inconsistency pointed out by Michael Attili
   <attili@amaxo.com>*

 * Fix for HMAC. It wasn't zeroing the rest of the block if the key length
   was larger than the MD block size.

   *Steve Henson, pointed out by Yost William <YostW@tce.com>*

 * Modernise PKCS12_parse() so it uses STACK_OF(X509) for its ca argument
   fix a leak when the ca argument was passed as NULL. Stop X509_PUBKEY_set()
   using the passed key: if the passed key was a private key the result
   of X509_print(), for example, would be to print out all the private key
   components.

   *Steve Henson*

 * des_quad_cksum() byte order bug fix.
   *Ulf Möller, using the problem description in krb4-0.9.7, where
   the solution is attributed to Derrick J Brashear <shadow@DEMENTIA.ORG>*

 * Fix so V_ASN1_APP_CHOOSE works again: however its use is strongly
   discouraged.

   *Steve Henson, pointed out by Brian Korver <briank@cs.stanford.edu>*

 * For easily testing in shell scripts whether some command
   'openssl XXX' exists, the new pseudo-command 'openssl no-XXX'
   returns with exit code 0 iff no command of the given name is available.
   'no-XXX' is printed in this case, 'XXX' otherwise.  In both cases,
   the output goes to stdout and nothing is printed to stderr.
   Additional arguments are always ignored.

   Since for each cipher there is a command of the same name,
   the 'no-cipher' compilation switches can be tested this way.

   ('openssl no-XXX' is not able to detect pseudo-commands such
   as 'quit', 'list-XXX-commands', or 'no-XXX' itself.)

   *Bodo Moeller*

 * Update test suite so that 'make test' succeeds in 'no-rsa' configuration.

   *Bodo Moeller*

 * For SSL_[CTX_]set_tmp_dh, don't create a DH key if SSL_OP_SINGLE_DH_USE
   is set; it will be thrown away anyway because each handshake creates
   its own key.
   ssl_cert_dup, which is used by SSL_new, now copies DH keys in addition
   to parameters -- in previous versions (since OpenSSL 0.9.3) the
   'default key' from SSL_CTX_set_tmp_dh would always be lost, meaning
   you effectively got SSL_OP_SINGLE_DH_USE when using this macro.

   *Bodo Moeller*

 * New s_client option -ign_eof: EOF at stdin is ignored, and
   'Q' and 'R' lose their special meanings (quit/renegotiate).
   This is part of what -quiet does; unlike -quiet, -ign_eof
   does not suppress any output.

   *Richard Levitte*

 * Add compatibility options to the purpose and trust code. The
   purpose X509_PURPOSE_ANY is "any purpose" which automatically
   accepts a certificate or CA, this was the previous behaviour,
   with all the associated security issues.

   X509_TRUST_COMPAT is the old trust behaviour: only and
   automatically trust self signed roots in certificate store. A
   new trust setting X509_TRUST_DEFAULT is used to specify that
   a purpose has no associated trust setting and it should instead
   use the value in the default purpose.

   *Steve Henson*

 * Fix the PKCS#8 DSA private key code so it decodes keys again
   and fix a memory leak.

   *Steve Henson*

 * In util/mkerr.pl (which implements 'make errors'), preserve
   reason strings from the previous version of the .c file, as
   the default to have only downcase letters (and digits) in
   automatically generated reasons codes is not always appropriate.

   *Bodo Moeller*

 * In ERR_load_ERR_strings(), build an ERR_LIB_SYS error reason table
   using strerror.  Previously, ERR_reason_error_string() returned
   library names as reason strings for SYSerr; but SYSerr is a special
   case where small numbers are errno values, not library numbers.

   *Bodo Moeller*

 * Add '-dsaparam' option to 'openssl dhparam' application.  This
   converts DSA parameters into DH parameters. (When creating parameters,
   DSA_generate_parameters is used.)

   *Bodo Moeller*

 * Include 'length' (recommended exponent length) in C code generated
   by 'openssl dhparam -C'.

   *Bodo Moeller*

 * The second argument to set_label in perlasm was already being used
   so couldn't be used as a "file scope" flag. Moved to third argument
   which was free.

   *Steve Henson*

 * In PEM_ASN1_write_bio and some other functions, use RAND_pseudo_bytes
   instead of RAND_bytes for encryption IVs and salts.

   *Bodo Moeller*

 * Include RAND_status() into RAND_METHOD instead of implementing
   it only for md_rand.c  Otherwise replacing the PRNG by calling
   RAND_set_rand_method would be impossible.

   *Bodo Moeller*

 * Don't let DSA_generate_key() enter an infinite loop if the random
   number generation fails.

   *Bodo Moeller*

 * New 'rand' application for creating pseudo-random output.

   *Bodo Moeller*

 * Added configuration support for Linux/IA64

   *Rolf Haberrecker <rolf@suse.de>*

 * Assembler module support for Mingw32.

   *Ulf Möller*

 * Shared library support for HPUX (in shlib/).

   *Lutz Jaenicke <Lutz.Jaenicke@aet.TU-Cottbus.DE> and Anonymous*

 * Shared library support for Solaris gcc.

   *Lutz Behnke <behnke@trustcenter.de>*

### Changes between 0.9.4 and 0.9.5  [28 Feb 2000]

 * PKCS7_encrypt() was adding text MIME headers twice because they
   were added manually and by SMIME_crlf_copy().

   *Steve Henson*

 * In bntest.c don't call BN_rand with zero bits argument.

   *Steve Henson, pointed out by Andrew W. Gray <agray@iconsinc.com>*

 * BN_mul bugfix: In bn_mul_part_recursion() only the a>a[n] && b>b[n]
   case was implemented. This caused BN_div_recp() to fail occasionally.

   *Ulf Möller*

 * Add an optional second argument to the set_label() in the perl
   assembly language builder. If this argument exists and is set
   to 1 it signals that the assembler should use a symbol whose
   scope is the entire file, not just the current function. This
   is needed with MASM which uses the format label:: for this scope.

   *Steve Henson, pointed out by Peter Runestig <peter@runestig.com>*

 * Change the ASN1 types so they are typedefs by default. Before
   almost all types were #define'd to ASN1_STRING which was causing
   STACK_OF() problems: you couldn't declare STACK_OF(ASN1_UTF8STRING)
   for example.

   *Steve Henson*

 * Change names of new functions to the new get1/get0 naming
   convention: After 'get1', the caller owns a reference count
   and has to call `..._free`; 'get0' returns a pointer to some
   data structure without incrementing reference counters.
   (Some of the existing 'get' functions increment a reference
   counter, some don't.)
   Similarly, 'set1' and 'add1' functions increase reference
   counters or duplicate objects.

   *Steve Henson*

 * Allow for the possibility of temp RSA key generation failure:
   the code used to assume it always worked and crashed on failure.

   *Steve Henson*

 * Fix potential buffer overrun problem in BIO_printf().
   *Ulf Möller, using public domain code by Patrick Powell; problem
   pointed out by David Sacerdote <das33@cornell.edu>*

 * Support EGD <http://www.lothar.com/tech/crypto/>.  New functions
   RAND_egd() and RAND_status().  In the command line application,
   the EGD socket can be specified like a seed file using RANDFILE
   or -rand.

   *Ulf Möller*

 * Allow the string CERTIFICATE to be tolerated in PKCS#7 structures.
   Some CAs (e.g. Verisign) distribute certificates in this form.

   *Steve Henson*

 * Remove the SSL_ALLOW_ADH compile option and set the default cipher
   list to exclude them. This means that no special compilation option
   is needed to use anonymous DH: it just needs to be included in the
   cipher list.

   *Steve Henson*

 * Change the EVP_MD_CTX_type macro so its meaning consistent with
   EVP_MD_type. The old functionality is available in a new macro called
   EVP_MD_md(). Change code that uses it and update docs.

   *Steve Henson*

 * `..._ctrl` functions now have corresponding `..._callback_ctrl` functions
   where the `void *` argument is replaced by a function pointer argument.
   Previously `void *` was abused to point to functions, which works on
   many platforms, but is not correct.  As these functions are usually
   called by macros defined in OpenSSL header files, most source code
   should work without changes.

   *Richard Levitte*

 * `<openssl/opensslconf.h>` (which is created by Configure) now contains
   sections with information on -D... compiler switches used for
   compiling the library so that applications can see them.  To enable
   one of these sections, a pre-processor symbol `OPENSSL_..._DEFINES`
   must be defined.  E.g.,
           #define OPENSSL_ALGORITHM_DEFINES
           #include <openssl/opensslconf.h>
   defines all pertinent `NO_<algo>` symbols, such as NO_IDEA, NO_RSA, etc.

   *Richard Levitte, Ulf and Bodo Möller*

 * Bugfix: Tolerate fragmentation and interleaving in the SSL 3/TLS
   record layer.

   *Bodo Moeller*

 * Change the 'other' type in certificate aux info to a STACK_OF
   X509_ALGOR. Although not an AlgorithmIdentifier as such it has
   the required ASN1 format: arbitrary types determined by an OID.

   *Steve Henson*

 * Add some PEM_write_X509_REQ_NEW() functions and a command line
   argument to 'req'. This is not because the function is newer or
   better than others it just uses the work 'NEW' in the certificate
   request header lines. Some software needs this.

   *Steve Henson*

 * Reorganise password command line arguments: now passwords can be
   obtained from various sources. Delete the PEM_cb function and make
   it the default behaviour: i.e. if the callback is NULL and the
   usrdata argument is not NULL interpret it as a null terminated pass
   phrase. If usrdata and the callback are NULL then the pass phrase
   is prompted for as usual.

   *Steve Henson*

 * Add support for the Compaq Atalla crypto accelerator. If it is installed,
   the support is automatically enabled. The resulting binaries will
   autodetect the card and use it if present.

   *Ben Laurie and Compaq Inc.*

 * Work around for Netscape hang bug. This sends certificate request
   and server done in one record. Since this is perfectly legal in the
   SSL/TLS protocol it isn't a "bug" option and is on by default. See
   the bugs/SSLv3 entry for more info.

   *Steve Henson*

 * HP-UX tune-up: new unified configs, HP C compiler bug workaround.

   *Andy Polyakov*

 * Add -rand argument to smime and pkcs12 applications and read/write
   of seed file.

   *Steve Henson*

 * New 'passwd' tool for crypt(3) and apr1 password hashes.

   *Bodo Moeller*

 * Add command line password options to the remaining applications.

   *Steve Henson*

 * Bug fix for BN_div_recp() for numerators with an even number of
   bits.

   *Ulf Möller*

 * More tests in bntest.c, and changed test_bn output.

   *Ulf Möller*

 * ./config recognizes MacOS X now.

   *Andy Polyakov*

 * Bug fix for BN_div() when the first words of num and divisor are
   equal (it gave wrong results if `(rem=(n1-q*d0)&BN_MASK2) < d0)`.

   *Ulf Möller*

 * Add support for various broken PKCS#8 formats, and command line
   options to produce them.

   *Steve Henson*

 * New functions BN_CTX_start(), BN_CTX_get() and BT_CTX_end() to
   get temporary BIGNUMs from a BN_CTX.

   *Ulf Möller*

 * Correct return values in BN_mod_exp_mont() and BN_mod_exp2_mont()
   for p == 0.

   *Ulf Möller*

 * Change the `SSLeay_add_all_*()` functions to `OpenSSL_add_all_*()` and
   include a #define from the old name to the new. The original intent
   was that statically linked binaries could for example just call
   SSLeay_add_all_ciphers() to just add ciphers to the table and not
   link with digests. This never worked because SSLeay_add_all_digests()
   and SSLeay_add_all_ciphers() were in the same source file so calling
   one would link with the other. They are now in separate source files.

   *Steve Henson*

 * Add a new -notext option to 'ca' and a -pubkey option to 'spkac'.

   *Steve Henson*

 * Use a less unusual form of the Miller-Rabin primality test (it used
   a binary algorithm for exponentiation integrated into the Miller-Rabin
   loop, our standard modexp algorithms are faster).

   *Bodo Moeller*

 * Support for the EBCDIC character set completed.

   *Martin Kraemer <Martin.Kraemer@Mch.SNI.De>*

 * Source code cleanups: use const where appropriate, eliminate casts,
   use `void *` instead of `char *` in lhash.

   *Ulf Möller*

 * Bugfix: ssl3_send_server_key_exchange was not restartable
   (the state was not changed to SSL3_ST_SW_KEY_EXCH_B, and because of
   this the server could overwrite ephemeral keys that the client
   has already seen).

   *Bodo Moeller*

 * Turn DSA_is_prime into a macro that calls BN_is_prime,
   using 50 iterations of the Rabin-Miller test.

   DSA_generate_parameters now uses BN_is_prime_fasttest (with 50
   iterations of the Rabin-Miller test as required by the appendix
   to FIPS PUB 186[-1]) instead of DSA_is_prime.
   As BN_is_prime_fasttest includes trial division, DSA parameter
   generation becomes much faster.

   This implies a change for the callback functions in DSA_is_prime
   and DSA_generate_parameters: The callback function is called once
   for each positive witness in the Rabin-Miller test, not just
   occasionally in the inner loop; and the parameters to the
   callback function now provide an iteration count for the outer
   loop rather than for the current invocation of the inner loop.
   DSA_generate_parameters additionally can call the callback
   function with an 'iteration count' of -1, meaning that a
   candidate has passed the trial division test (when q is generated
   from an application-provided seed, trial division is skipped).

   *Bodo Moeller*

 * New function BN_is_prime_fasttest that optionally does trial
   division before starting the Rabin-Miller test and has
   an additional BN_CTX * argument (whereas BN_is_prime always
   has to allocate at least one BN_CTX).
   'callback(1, -1, cb_arg)' is called when a number has passed the
   trial division stage.

   *Bodo Moeller*

 * Fix for bug in CRL encoding. The validity dates weren't being handled
   as ASN1_TIME.

   *Steve Henson*

 * New -pkcs12 option to CA.pl script to write out a PKCS#12 file.

   *Steve Henson*

 * New function BN_pseudo_rand().

   *Ulf Möller*

 * Clean up BN_mod_mul_montgomery(): replace the broken (and unreadable)
   bignum version of BN_from_montgomery() with the working code from
   SSLeay 0.9.0 (the word based version is faster anyway), and clean up
   the comments.

   *Ulf Möller*

 * Avoid a race condition in s2_clnt.c (function get_server_hello) that
   made it impossible to use the same SSL_SESSION data structure in
   SSL2 clients in multiple threads.

   *Bodo Moeller*

 * The return value of RAND_load_file() no longer counts bytes obtained
   by stat().  RAND_load_file(..., -1) is new and uses the complete file
   to seed the PRNG (previously an explicit byte count was required).

   *Ulf Möller, Bodo Möller*

 * Clean up CRYPTO_EX_DATA functions, some of these didn't have prototypes
   used `char *` instead of `void *` and had casts all over the place.

   *Steve Henson*

 * Make BN_generate_prime() return NULL on error if ret!=NULL.

   *Ulf Möller*

 * Retain source code compatibility for BN_prime_checks macro:
   BN_is_prime(..., BN_prime_checks, ...) now uses
   BN_prime_checks_for_size to determine the appropriate number of
   Rabin-Miller iterations.

   *Ulf Möller*

 * Diffie-Hellman uses "safe" primes: DH_check() return code renamed to
   DH_CHECK_P_NOT_SAFE_PRIME.
   (Check if this is true? OpenPGP calls them "strong".)

   *Ulf Möller*

 * Merge the functionality of "dh" and "gendh" programs into a new program
   "dhparam". The old programs are retained for now but will handle DH keys
   (instead of parameters) in future.

   *Steve Henson*

 * Make the ciphers, s_server and s_client programs check the return values
   when a new cipher list is set.

   *Steve Henson*

 * Enhance the SSL/TLS cipher mechanism to correctly handle the TLS 56bit
   ciphers. Before when the 56bit ciphers were enabled the sorting was
   wrong.

   The syntax for the cipher sorting has been extended to support sorting by
   cipher-strength (using the strength_bits hard coded in the tables).
   The new command is `@STRENGTH` (see also `doc/apps/ciphers.pod`).

   Fix a bug in the cipher-command parser: when supplying a cipher command
   string with an "undefined" symbol (neither command nor alphanumeric
   *A-Za-z0-9*, ssl_set_cipher_list used to hang in an endless loop. Now
   an error is flagged.

   Due to the strength-sorting extension, the code of the
   ssl_create_cipher_list() function was completely rearranged. I hope that
   the readability was also increased :-)

   *Lutz Jaenicke <Lutz.Jaenicke@aet.TU-Cottbus.DE>*

 * Minor change to 'x509' utility. The -CAcreateserial option now uses 1
   for the first serial number and places 2 in the serial number file. This
   avoids problems when the root CA is created with serial number zero and
   the first user certificate has the same issuer name and serial number
   as the root CA.

   *Steve Henson*

 * Fixes to X509_ATTRIBUTE utilities, change the 'req' program so it uses
   the new code. Add documentation for this stuff.

   *Steve Henson*

 * Changes to X509_ATTRIBUTE utilities. These have been renamed from
   `X509_*()` to `X509at_*()` on the grounds that they don't handle X509
   structures and behave in an analogous way to the X509v3 functions:
   they shouldn't be called directly but wrapper functions should be used
   instead.

   So we also now have some wrapper functions that call the X509at functions
   when passed certificate requests. (TO DO: similar things can be done with
   PKCS#7 signed and unsigned attributes, PKCS#12 attributes and a few other
   things. Some of these need some d2i or i2d and print functionality
   because they handle more complex structures.)

   *Steve Henson*

 * Add missing #ifndefs that caused missing symbols when building libssl
   as a shared library without RSA.  Use #ifndef NO_SSL2 instead of
   NO_RSA in `ssl/s2*.c`.

   *Kris Kennaway <kris@hub.freebsd.org>, modified by Ulf Möller*

 * Precautions against using the PRNG uninitialized: RAND_bytes() now
   has a return value which indicates the quality of the random data
   (1 = ok, 0 = not seeded).  Also an error is recorded on the thread's
   error queue. New function RAND_pseudo_bytes() generates output that is
   guaranteed to be unique but not unpredictable. RAND_add is like
   RAND_seed, but takes an extra argument for an entropy estimate
   (RAND_seed always assumes full entropy).

   *Ulf Möller*

 * Do more iterations of Rabin-Miller probable prime test (specifically,
   3 for 1024-bit primes, 6 for 512-bit primes, 12 for 256-bit primes
   instead of only 2 for all lengths; see BN_prime_checks_for_size definition
   in crypto/bn/bn_prime.c for the complete table).  This guarantees a
   false-positive rate of at most 2^-80 for random input.

   *Bodo Moeller*

 * Rewrite ssl3_read_n (ssl/s3_pkt.c) avoiding a couple of bugs.

   *Bodo Moeller*

 * New function X509_CTX_rget_chain() (renamed to X509_CTX_get1_chain
   in the 0.9.5 release), this returns the chain
   from an X509_CTX structure with a dup of the stack and all
   the X509 reference counts upped: so the stack will exist
   after X509_CTX_cleanup() has been called. Modify pkcs12.c
   to use this.

   Also make SSL_SESSION_print() print out the verify return
   code.

   *Steve Henson*

 * Add manpage for the pkcs12 command. Also change the default
   behaviour so MAC iteration counts are used unless the new
   -nomaciter option is used. This improves file security and
   only older versions of MSIE (4.0 for example) need it.

   *Steve Henson*

 * Honor the no-xxx Configure options when creating .DEF files.

   *Ulf Möller*

 * Add PKCS#10 attributes to field table: challengePassword,
   unstructuredName and unstructuredAddress. These are taken from
   draft PKCS#9 v2.0 but are compatible with v1.2 provided no
   international characters are used.

   More changes to X509_ATTRIBUTE code: allow the setting of types
   based on strings. Remove the 'loc' parameter when adding
   attributes because these will be a SET OF encoding which is sorted
   in ASN1 order.

   *Steve Henson*

 * Initial changes to the 'req' utility to allow request generation
   automation. This will allow an application to just generate a template
   file containing all the field values and have req construct the
   request.

   Initial support for X509_ATTRIBUTE handling. Stacks of these are
   used all over the place including certificate requests and PKCS#7
   structures. They are currently handled manually where necessary with
   some primitive wrappers for PKCS#7. The new functions behave in a
   manner analogous to the X509 extension functions: they allow
   attributes to be looked up by NID and added.

   Later something similar to the X509V3 code would be desirable to
   automatically handle the encoding, decoding and printing of the
   more complex types. The string types like challengePassword can
   be handled by the string table functions.

   Also modified the multi byte string table handling. Now there is
   a 'global mask' which masks out certain types. The table itself
   can use the flag STABLE_NO_MASK to ignore the mask setting: this
   is useful when for example there is only one permissible type
   (as in countryName) and using the mask might result in no valid
   types at all.

   *Steve Henson*

 * Clean up 'Finished' handling, and add functions SSL_get_finished and
   SSL_get_peer_finished to allow applications to obtain the latest
   Finished messages sent to the peer or expected from the peer,
   respectively.  (SSL_get_peer_finished is usually the Finished message
   actually received from the peer, otherwise the protocol will be aborted.)

   As the Finished message are message digests of the complete handshake
   (with a total of 192 bits for TLS 1.0 and more for SSL 3.0), they can
   be used for external authentication procedures when the authentication
   provided by SSL/TLS is not desired or is not enough.

   *Bodo Moeller*

 * Enhanced support for Alpha Linux is added. Now ./config checks if
   the host supports BWX extension and if Compaq C is present on the
   $PATH. Just exploiting of the BWX extension results in 20-30%
   performance kick for some algorithms, e.g. DES and RC4 to mention
   a couple. Compaq C in turn generates ~20% faster code for MD5 and
   SHA1.

   *Andy Polyakov*

 * Add support for MS "fast SGC". This is arguably a violation of the
   SSL3/TLS protocol. Netscape SGC does two handshakes: the first with
   weak crypto and after checking the certificate is SGC a second one
   with strong crypto. MS SGC stops the first handshake after receiving
   the server certificate message and sends a second client hello. Since
   a server will typically do all the time consuming operations before
   expecting any further messages from the client (server key exchange
   is the most expensive) there is little difference between the two.

   To get OpenSSL to support MS SGC we have to permit a second client
   hello message after we have sent server done. In addition we have to
   reset the MAC if we do get this second client hello.

   *Steve Henson*

 * Add a function 'd2i_AutoPrivateKey()' this will automatically decide
   if a DER encoded private key is RSA or DSA traditional format. Changed
   d2i_PrivateKey_bio() to use it. This is only needed for the "traditional"
   format DER encoded private key. Newer code should use PKCS#8 format which
   has the key type encoded in the ASN1 structure. Added DER private key
   support to pkcs8 application.

   *Steve Henson*

 * SSL 3/TLS 1 servers now don't request certificates when an anonymous
   ciphersuites has been selected (as required by the SSL 3/TLS 1
   specifications).  Exception: When SSL_VERIFY_FAIL_IF_NO_PEER_CERT
   is set, we interpret this as a request to violate the specification
   (the worst that can happen is a handshake failure, and 'correct'
   behaviour would result in a handshake failure anyway).

   *Bodo Moeller*

 * In SSL_CTX_add_session, take into account that there might be multiple
   SSL_SESSION structures with the same session ID (e.g. when two threads
   concurrently obtain them from an external cache).
   The internal cache can handle only one SSL_SESSION with a given ID,
   so if there's a conflict, we now throw out the old one to achieve
   consistency.

   *Bodo Moeller*

 * Add OIDs for idea and blowfish in CBC mode. This will allow both
   to be used in PKCS#5 v2.0 and S/MIME.  Also add checking to
   some routines that use cipher OIDs: some ciphers do not have OIDs
   defined and so they cannot be used for S/MIME and PKCS#5 v2.0 for
   example.

   *Steve Henson*

 * Simplify the trust setting structure and code. Now we just have
   two sequences of OIDs for trusted and rejected settings. These will
   typically have values the same as the extended key usage extension
   and any application specific purposes.

   The trust checking code now has a default behaviour: it will just
   check for an object with the same NID as the passed id. Functions can
   be provided to override either the default behaviour or the behaviour
   for a given id. SSL client, server and email already have functions
   in place for compatibility: they check the NID and also return "trusted"
   if the certificate is self signed.

   *Steve Henson*

 * Add d2i,i2d bio/fp functions for PrivateKey: these convert the
   traditional format into an EVP_PKEY structure.

   *Steve Henson*

 * Add a password callback function PEM_cb() which either prompts for
   a password if usr_data is NULL or otherwise assumes it is a null
   terminated password. Allow passwords to be passed on command line
   environment or config files in a few more utilities.

   *Steve Henson*

 * Add a bunch of DER and PEM functions to handle PKCS#8 format private
   keys. Add some short names for PKCS#8 PBE algorithms and allow them
   to be specified on the command line for the pkcs8 and pkcs12 utilities.
   Update documentation.

   *Steve Henson*

 * Support for ASN1 "NULL" type. This could be handled before by using
   ASN1_TYPE but there wasn't any function that would try to read a NULL
   and produce an error if it couldn't. For compatibility we also have
   ASN1_NULL_new() and ASN1_NULL_free() functions but these are faked and
   don't allocate anything because they don't need to.

   *Steve Henson*

 * Initial support for MacOS is now provided. Examine INSTALL.MacOS
   for details.

   *Andy Polyakov, Roy Woods <roy@centicsystems.ca>*

 * Rebuild of the memory allocation routines used by OpenSSL code and
   possibly others as well.  The purpose is to make an interface that
   provide hooks so anyone can build a separate set of allocation and
   deallocation routines to be used by OpenSSL, for example memory
   pool implementations, or something else, which was previously hard
   since Malloc(), Realloc() and Free() were defined as macros having
   the values malloc, realloc and free, respectively (except for Win32
   compilations).  The same is provided for memory debugging code.
   OpenSSL already comes with functionality to find memory leaks, but
   this gives people a chance to debug other memory problems.

   With these changes, a new set of functions and macros have appeared:

     CRYPTO_set_mem_debug_functions()         [F]
     CRYPTO_get_mem_debug_functions()         [F]
     CRYPTO_dbg_set_options()                 [F]
     CRYPTO_dbg_get_options()                 [F]
     CRYPTO_malloc_debug_init()               [M]

   The memory debug functions are NULL by default, unless the library
   is compiled with CRYPTO_MDEBUG or friends is defined.  If someone
   wants to debug memory anyway, CRYPTO_malloc_debug_init() (which
   gives the standard debugging functions that come with OpenSSL) or
   CRYPTO_set_mem_debug_functions() (tells OpenSSL to use functions
   provided by the library user) must be used.  When the standard
   debugging functions are used, CRYPTO_dbg_set_options can be used to
   request additional information:
   CRYPTO_dbg_set_options(V_CYRPTO_MDEBUG_xxx) corresponds to setting
   the CRYPTO_MDEBUG_xxx macro when compiling the library.

   Also, things like CRYPTO_set_mem_functions will always give the
   expected result (the new set of functions is used for allocation
   and deallocation) at all times, regardless of platform and compiler
   options.

   To finish it up, some functions that were never use in any other
   way than through macros have a new API and new semantic:

     CRYPTO_dbg_malloc()
     CRYPTO_dbg_realloc()
     CRYPTO_dbg_free()

   All macros of value have retained their old syntax.

   *Richard Levitte and Bodo Moeller*

 * Some S/MIME fixes. The OID for SMIMECapabilities was wrong, the
   ordering of SMIMECapabilities wasn't in "strength order" and there
   was a missing NULL in the AlgorithmIdentifier for the SHA1 signature
   algorithm.

   *Steve Henson*

 * Some ASN1 types with illegal zero length encoding (INTEGER,
   ENUMERATED and OBJECT IDENTIFIER) choked the ASN1 routines.

   *Frans Heymans <fheymans@isaserver.be>, modified by Steve Henson*

 * Merge in my S/MIME library for OpenSSL. This provides a simple
   S/MIME API on top of the PKCS#7 code, a MIME parser (with enough
   functionality to handle multipart/signed properly) and a utility
   called 'smime' to call all this stuff. This is based on code I
   originally wrote for Celo who have kindly allowed it to be
   included in OpenSSL.

   *Steve Henson*

 * Add variants des_set_key_checked and des_set_key_unchecked of
   des_set_key (aka des_key_sched).  Global variable des_check_key
   decides which of these is called by des_set_key; this way
   des_check_key behaves as it always did, but applications and
   the library itself, which was buggy for des_check_key == 1,
   have a cleaner way to pick the version they need.

   *Bodo Moeller*

 * New function PKCS12_newpass() which changes the password of a
   PKCS12 structure.

   *Steve Henson*

 * Modify X509_TRUST and X509_PURPOSE so it also uses a static and
   dynamic mix. In both cases the ids can be used as an index into the
   table. Also modified the X509_TRUST_add() and X509_PURPOSE_add()
   functions so they accept a list of the field values and the
   application doesn't need to directly manipulate the X509_TRUST
   structure.

   *Steve Henson*

 * Modify the ASN1_STRING_TABLE stuff so it also uses bsearch and doesn't
   need initialising.

   *Steve Henson*

 * Modify the way the V3 extension code looks up extensions. This now
   works in a similar way to the object code: we have some "standard"
   extensions in a static table which is searched with OBJ_bsearch()
   and the application can add dynamic ones if needed. The file
   crypto/x509v3/ext_dat.h now has the info: this file needs to be
   updated whenever a new extension is added to the core code and kept
   in ext_nid order. There is a simple program 'tabtest.c' which checks
   this. New extensions are not added too often so this file can readily
   be maintained manually.

   There are two big advantages in doing things this way. The extensions
   can be looked up immediately and no longer need to be "added" using
   X509V3_add_standard_extensions(): this function now does nothing.
   Side note: I get *lots* of email saying the extension code doesn't
   work because people forget to call this function.
   Also no dynamic allocation is done unless new extensions are added:
   so if we don't add custom extensions there is no need to call
   X509V3_EXT_cleanup().

   *Steve Henson*

 * Modify enc utility's salting as follows: make salting the default. Add a
   magic header, so unsalted files fail gracefully instead of just decrypting
   to garbage. This is because not salting is a big security hole, so people
   should be discouraged from doing it.

   *Ben Laurie*

 * Fixes and enhancements to the 'x509' utility. It allowed a message
   digest to be passed on the command line but it only used this
   parameter when signing a certificate. Modified so all relevant
   operations are affected by the digest parameter including the
   -fingerprint and -x509toreq options. Also -x509toreq choked if a
   DSA key was used because it didn't fix the digest.

   *Steve Henson*

 * Initial certificate chain verify code. Currently tests the untrusted
   certificates for consistency with the verify purpose (which is set
   when the X509_STORE_CTX structure is set up) and checks the pathlength.

   There is a NO_CHAIN_VERIFY compilation option to keep the old behaviour:
   this is because it will reject chains with invalid extensions whereas
   every previous version of OpenSSL and SSLeay made no checks at all.

   Trust code: checks the root CA for the relevant trust settings. Trust
   settings have an initial value consistent with the verify purpose: e.g.
   if the verify purpose is for SSL client use it expects the CA to be
   trusted for SSL client use. However the default value can be changed to
   permit custom trust settings: one example of this would be to only trust
   certificates from a specific "secure" set of CAs.

   Also added X509_STORE_CTX_new() and X509_STORE_CTX_free() functions
   which should be used for version portability: especially since the
   verify structure is likely to change more often now.

   SSL integration. Add purpose and trust to SSL_CTX and SSL and functions
   to set them. If not set then assume SSL clients will verify SSL servers
   and vice versa.

   Two new options to the verify program: -untrusted allows a set of
   untrusted certificates to be passed in and -purpose which sets the
   intended purpose of the certificate. If a purpose is set then the
   new chain verify code is used to check extension consistency.

   *Steve Henson*

 * Support for the authority information access extension.

   *Steve Henson*

 * Modify RSA and DSA PEM read routines to transparently handle
   PKCS#8 format private keys. New *_PUBKEY_* functions that handle
   public keys in a format compatible with certificate
   SubjectPublicKeyInfo structures. Unfortunately there were already
   functions called *_PublicKey_* which used various odd formats so
   these are retained for compatibility: however the DSA variants were
   never in a public release so they have been deleted. Changed dsa/rsa
   utilities to handle the new format: note no releases ever handled public
   keys so we should be OK.

   The primary motivation for this change is to avoid the same fiasco
   that dogs private keys: there are several incompatible private key
   formats some of which are standard and some OpenSSL specific and
   require various evil hacks to allow partial transparent handling and
   even then it doesn't work with DER formats. Given the option anything
   other than PKCS#8 should be dumped: but the other formats have to
   stay in the name of compatibility.

   With public keys and the benefit of hindsight one standard format
   is used which works with EVP_PKEY, RSA or DSA structures: though
   it clearly returns an error if you try to read the wrong kind of key.

   Added a -pubkey option to the 'x509' utility to output the public key.
   Also rename the `EVP_PKEY_get_*()` to `EVP_PKEY_rget_*()`
   (renamed to `EVP_PKEY_get1_*()` in the OpenSSL 0.9.5 release) and add
   `EVP_PKEY_rset_*()` functions (renamed to `EVP_PKEY_set1_*()`)
   that do the same as the `EVP_PKEY_assign_*()` except they up the
   reference count of the added key (they don't "swallow" the
   supplied key).

   *Steve Henson*

 * Fixes to crypto/x509/by_file.c the code to read in certificates and
   CRLs would fail if the file contained no certificates or no CRLs:
   added a new function to read in both types and return the number
   read: this means that if none are read it will be an error. The
   DER versions of the certificate and CRL reader would always fail
   because it isn't possible to mix certificates and CRLs in DER format
   without choking one or the other routine. Changed this to just read
   a certificate: this is the best we can do. Also modified the code
   in `apps/verify.c` to take notice of return codes: it was previously
   attempting to read in certificates from NULL pointers and ignoring
   any errors: this is one reason why the cert and CRL reader seemed
   to work. It doesn't check return codes from the default certificate
   routines: these may well fail if the certificates aren't installed.

   *Steve Henson*

 * Code to support otherName option in GeneralName.

   *Steve Henson*

 * First update to verify code. Change the verify utility
   so it warns if it is passed a self signed certificate:
   for consistency with the normal behaviour. X509_verify
   has been modified to it will now verify a self signed
   certificate if *exactly* the same certificate appears
   in the store: it was previously impossible to trust a
   single self signed certificate. This means that:
   openssl verify ss.pem
   now gives a warning about a self signed certificate but
   openssl verify -CAfile ss.pem ss.pem
   is OK.

   *Steve Henson*

 * For servers, store verify_result in SSL_SESSION data structure
   (and add it to external session representation).
   This is needed when client certificate verifications fails,
   but an application-provided verification callback (set by
   SSL_CTX_set_cert_verify_callback) allows accepting the session
   anyway (i.e. leaves x509_store_ctx->error != X509_V_OK
   but returns 1): When the session is reused, we have to set
   ssl->verify_result to the appropriate error code to avoid
   security holes.

   *Bodo Moeller, problem pointed out by Lutz Jaenicke*

 * Fix a bug in the new PKCS#7 code: it didn't consider the
   case in PKCS7_dataInit() where the signed PKCS7 structure
   didn't contain any existing data because it was being created.

   *Po-Cheng Chen <pocheng@nst.com.tw>, slightly modified by Steve Henson*

 * Add a salt to the key derivation routines in enc.c. This
   forms the first 8 bytes of the encrypted file. Also add a
   -S option to allow a salt to be input on the command line.

   *Steve Henson*

 * New function X509_cmp(). Oddly enough there wasn't a function
   to compare two certificates. We do this by working out the SHA1
   hash and comparing that. X509_cmp() will be needed by the trust
   code.

   *Steve Henson*

 * SSL_get1_session() is like SSL_get_session(), but increments
   the reference count in the SSL_SESSION returned.

   *Geoff Thorpe <geoff@eu.c2.net>*

 * Fix for 'req': it was adding a null to request attributes.
   Also change the X509_LOOKUP and X509_INFO code to handle
   certificate auxiliary information.

   *Steve Henson*

 * Add support for 40 and 64 bit RC2 and RC4 algorithms: document
   the 'enc' command.

   *Steve Henson*

 * Add the possibility to add extra information to the memory leak
   detecting output, to form tracebacks, showing from where each
   allocation was originated: CRYPTO_push_info("constant string") adds
   the string plus current file name and line number to a per-thread
   stack, CRYPTO_pop_info() does the obvious, CRYPTO_remove_all_info()
   is like calling CYRPTO_pop_info() until the stack is empty.
   Also updated memory leak detection code to be multi-thread-safe.

   *Richard Levitte*

 * Add options -text and -noout to pkcs7 utility and delete the
   encryption options which never did anything. Update docs.

   *Steve Henson*

 * Add options to some of the utilities to allow the pass phrase
   to be included on either the command line (not recommended on
   OSes like Unix) or read from the environment. Update the
   manpages and fix a few bugs.

   *Steve Henson*

 * Add a few manpages for some of the openssl commands.

   *Steve Henson*

 * Fix the -revoke option in ca. It was freeing up memory twice,
   leaking and not finding already revoked certificates.

   *Steve Henson*

 * Extensive changes to support certificate auxiliary information.
   This involves the use of X509_CERT_AUX structure and X509_AUX
   functions. An X509_AUX function such as PEM_read_X509_AUX()
   can still read in a certificate file in the usual way but it
   will also read in any additional "auxiliary information". By
   doing things this way a fair degree of compatibility can be
   retained: existing certificates can have this information added
   using the new 'x509' options.

   Current auxiliary information includes an "alias" and some trust
   settings. The trust settings will ultimately be used in enhanced
   certificate chain verification routines: currently a certificate
   can only be trusted if it is self signed and then it is trusted
   for all purposes.

   *Steve Henson*

 * Fix assembler for Alpha (tested only on DEC OSF not Linux or `*BSD`).
   The problem was that one of the replacement routines had not been working
   since SSLeay releases.  For now the offending routine has been replaced
   with non-optimised assembler.  Even so, this now gives around 95%
   performance improvement for 1024 bit RSA signs.

   *Mark Cox*

 * Hack to fix PKCS#7 decryption when used with some unorthodox RC2
   handling. Most clients have the effective key size in bits equal to
   the key length in bits: so a 40 bit RC2 key uses a 40 bit (5 byte) key.
   A few however don't do this and instead use the size of the decrypted key
   to determine the RC2 key length and the AlgorithmIdentifier to determine
   the effective key length. In this case the effective key length can still
   be 40 bits but the key length can be 168 bits for example. This is fixed
   by manually forcing an RC2 key into the EVP_PKEY structure because the
   EVP code can't currently handle unusual RC2 key sizes: it always assumes
   the key length and effective key length are equal.

   *Steve Henson*

 * Add a bunch of functions that should simplify the creation of
   X509_NAME structures. Now you should be able to do:
   X509_NAME_add_entry_by_txt(nm, "CN", MBSTRING_ASC, "Steve", -1, -1, 0);
   and have it automatically work out the correct field type and fill in
   the structures. The more adventurous can try:
   X509_NAME_add_entry_by_txt(nm, field, MBSTRING_UTF8, str, -1, -1, 0);
   and it will (hopefully) work out the correct multibyte encoding.

   *Steve Henson*

 * Change the 'req' utility to use the new field handling and multibyte
   copy routines. Before the DN field creation was handled in an ad hoc
   way in req, ca, and x509 which was rather broken and didn't support
   BMPStrings or UTF8Strings. Since some software doesn't implement
   BMPStrings or UTF8Strings yet, they can be enabled using the config file
   using the dirstring_type option. See the new comment in the default
   openssl.cnf for more info.

   *Steve Henson*

 * Make crypto/rand/md_rand.c more robust:
   - Assure unique random numbers after fork().
   - Make sure that concurrent threads access the global counter and
     md serializably so that we never lose entropy in them
     or use exactly the same state in multiple threads.
     Access to the large state is not always serializable because
     the additional locking could be a performance killer, and
     md should be large enough anyway.

   *Bodo Moeller*

 * New file `apps/app_rand.c` with commonly needed functionality
   for handling the random seed file.

   Use the random seed file in some applications that previously did not:
           ca,
           dsaparam -genkey (which also ignored its '-rand' option),
           s_client,
           s_server,
           x509 (when signing).
   Except on systems with /dev/urandom, it is crucial to have a random
   seed file at least for key creation, DSA signing, and for DH exchanges;
   for RSA signatures we could do without one.

   gendh and gendsa (unlike genrsa) used to read only the first byte
   of each file listed in the '-rand' option.  The function as previously
   found in genrsa is now in app_rand.c and is used by all programs
   that support '-rand'.

   *Bodo Moeller*

 * In RAND_write_file, use mode 0600 for creating files;
   don't just chmod when it may be too late.

   *Bodo Moeller*

 * Report an error from X509_STORE_load_locations
   when X509_LOOKUP_load_file or X509_LOOKUP_add_dir failed.

   *Bill Perry*

 * New function ASN1_mbstring_copy() this copies a string in either
   ASCII, Unicode, Universal (4 bytes per character) or UTF8 format
   into an ASN1_STRING type. A mask of permissible types is passed
   and it chooses the "minimal" type to use or an error if not type
   is suitable.

   *Steve Henson*

 * Add function equivalents to the various macros in asn1.h. The old
   macros are retained with an `M_` prefix. Code inside the library can
   use the `M_` macros. External code (including the openssl utility)
   should *NOT* in order to be "shared library friendly".

   *Steve Henson*

 * Add various functions that can check a certificate's extensions
   to see if it usable for various purposes such as SSL client,
   server or S/MIME and CAs of these types. This is currently
   VERY EXPERIMENTAL but will ultimately be used for certificate chain
   verification. Also added a -purpose flag to x509 utility to
   print out all the purposes.

   *Steve Henson*

 * Add a CRYPTO_EX_DATA to X509 certificate structure and associated
   functions.

   *Steve Henson*

 * New `X509V3_{X509,CRL,REVOKED}_get_d2i()` functions. These will search
   for, obtain and decode and extension and obtain its critical flag.
   This allows all the necessary extension code to be handled in a
   single function call.

   *Steve Henson*

 * RC4 tune-up featuring 30-40% performance improvement on most RISC
   platforms. See crypto/rc4/rc4_enc.c for further details.

   *Andy Polyakov*

 * New -noout option to asn1parse. This causes no output to be produced
   its main use is when combined with -strparse and -out to extract data
   from a file (which may not be in ASN.1 format).

   *Steve Henson*

 * Fix for pkcs12 program. It was hashing an invalid certificate pointer
   when producing the local key id.

   *Richard Levitte <levitte@stacken.kth.se>*

 * New option -dhparam in s_server. This allows a DH parameter file to be
   stated explicitly. If it is not stated then it tries the first server
   certificate file. The previous behaviour hard coded the filename
   "server.pem".

   *Steve Henson*

 * Add -pubin and -pubout options to the rsa and dsa commands. These allow
   a public key to be input or output. For example:
   openssl rsa -in key.pem -pubout -out pubkey.pem
   Also added necessary DSA public key functions to handle this.

   *Steve Henson*

 * Fix so PKCS7_dataVerify() doesn't crash if no certificates are contained
   in the message. This was handled by allowing
   X509_find_by_issuer_and_serial() to tolerate a NULL passed to it.

   *Steve Henson, reported by Sampo Kellomaki <sampo@mail.neuronio.pt>*

 * Fix for bug in d2i_ASN1_bytes(): other ASN1 functions add an extra null
   to the end of the strings whereas this didn't. This would cause problems
   if strings read with d2i_ASN1_bytes() were later modified.

   *Steve Henson, reported by Arne Ansper <arne@ats.cyber.ee>*

 * Fix for base64 decode bug. When a base64 bio reads only one line of
   data and it contains EOF it will end up returning an error. This is
   caused by input 46 bytes long. The cause is due to the way base64
   BIOs find the start of base64 encoded data. They do this by trying a
   trial decode on each line until they find one that works. When they
   do a flag is set and it starts again knowing it can pass all the
   data directly through the decoder. Unfortunately it doesn't reset
   the context it uses. This means that if EOF is reached an attempt
   is made to pass two EOFs through the context and this causes the
   resulting error. This can also cause other problems as well. As is
   usual with these problems it takes *ages* to find and the fix is
   trivial: move one line.

   *Steve Henson, reported by ian@uns.ns.ac.yu (Ivan Nejgebauer)*

 * Ugly workaround to get s_client and s_server working under Windows. The
   old code wouldn't work because it needed to select() on sockets and the
   tty (for keypresses and to see if data could be written). Win32 only
   supports select() on sockets so we select() with a 1s timeout on the
   sockets and then see if any characters are waiting to be read, if none
   are present then we retry, we also assume we can always write data to
   the tty. This isn't nice because the code then blocks until we've
   received a complete line of data and it is effectively polling the
   keyboard at 1s intervals: however it's quite a bit better than not
   working at all :-) A dedicated Windows application might handle this
   with an event loop for example.

   *Steve Henson*

 * Enhance RSA_METHOD structure. Now there are two extra methods, rsa_sign
   and rsa_verify. When the RSA_FLAGS_SIGN_VER option is set these functions
   will be called when RSA_sign() and RSA_verify() are used. This is useful
   if rsa_pub_dec() and rsa_priv_enc() equivalents are not available.
   For this to work properly RSA_public_decrypt() and RSA_private_encrypt()
   should *not* be used: RSA_sign() and RSA_verify() must be used instead.
   This necessitated the support of an extra signature type NID_md5_sha1
   for SSL signatures and modifications to the SSL library to use it instead
   of calling RSA_public_decrypt() and RSA_private_encrypt().

   *Steve Henson*

 * Add new -verify -CAfile and -CApath options to the crl program, these
   will lookup a CRL issuers certificate and verify the signature in a
   similar way to the verify program. Tidy up the crl program so it
   no longer accesses structures directly. Make the ASN1 CRL parsing a bit
   less strict. It will now permit CRL extensions even if it is not
   a V2 CRL: this will allow it to tolerate some broken CRLs.

   *Steve Henson*

 * Initialize all non-automatic variables each time one of the openssl
   sub-programs is started (this is necessary as they may be started
   multiple times from the "OpenSSL>" prompt).

   *Lennart Bang, Bodo Moeller*

 * Preliminary compilation option RSA_NULL which disables RSA crypto without
   removing all other RSA functionality (this is what NO_RSA does). This
   is so (for example) those in the US can disable those operations covered
   by the RSA patent while allowing storage and parsing of RSA keys and RSA
   key generation.

   *Steve Henson*

 * Non-copying interface to BIO pairs.
   (still largely untested)

   *Bodo Moeller*

 * New function ASN1_tag2str() to convert an ASN1 tag to a descriptive
   ASCII string. This was handled independently in various places before.

   *Steve Henson*

 * New functions UTF8_getc() and UTF8_putc() that parse and generate
   UTF8 strings a character at a time.

   *Steve Henson*

 * Use client_version from client hello to select the protocol
   (s23_srvr.c) and for RSA client key exchange verification
   (s3_srvr.c), as required by the SSL 3.0/TLS 1.0 specifications.

   *Bodo Moeller*

 * Add various utility functions to handle SPKACs, these were previously
   handled by poking round in the structure internals. Added new function
   NETSCAPE_SPKI_print() to print out SPKAC and a new utility 'spkac' to
   print, verify and generate SPKACs. Based on an original idea from
   Massimiliano Pala <madwolf@comune.modena.it> but extensively modified.

   *Steve Henson*

 * RIPEMD160 is operational on all platforms and is back in 'make test'.

   *Andy Polyakov*

 * Allow the config file extension section to be overwritten on the
   command line. Based on an original idea from Massimiliano Pala
   <madwolf@comune.modena.it>. The new option is called -extensions
   and can be applied to ca, req and x509. Also -reqexts to override
   the request extensions in req and -crlexts to override the crl extensions
   in ca.

   *Steve Henson*

 * Add new feature to the SPKAC handling in ca.  Now you can include
   the same field multiple times by preceding it by "XXXX." for example:
   1.OU="Unit name 1"
   2.OU="Unit name 2"
   this is the same syntax as used in the req config file.

   *Steve Henson*

 * Allow certificate extensions to be added to certificate requests. These
   are specified in a 'req_extensions' option of the req section of the
   config file. They can be printed out with the -text option to req but
   are otherwise ignored at present.

   *Steve Henson*

 * Fix a horrible bug in enc_read() in crypto/evp/bio_enc.c: if the first
   data read consists of only the final block it would not decrypted because
   EVP_CipherUpdate() would correctly report zero bytes had been decrypted.
   A misplaced 'break' also meant the decrypted final block might not be
   copied until the next read.

   *Steve Henson*

 * Initial support for DH_METHOD. Again based on RSA_METHOD. Also added
   a few extra parameters to the DH structure: these will be useful if
   for example we want the value of 'q' or implement X9.42 DH.

   *Steve Henson*

 * Initial support for DSA_METHOD. This is based on the RSA_METHOD and
   provides hooks that allow the default DSA functions or functions on a
   "per key" basis to be replaced. This allows hardware acceleration and
   hardware key storage to be handled without major modification to the
   library. Also added low-level modexp hooks and CRYPTO_EX structure and
   associated functions.

   *Steve Henson*

 * Add a new flag to memory BIOs, BIO_FLAG_MEM_RDONLY. This marks the BIO
   as "read only": it can't be written to and the buffer it points to will
   not be freed. Reading from a read only BIO is much more efficient than
   a normal memory BIO. This was added because there are several times when
   an area of memory needs to be read from a BIO. The previous method was
   to create a memory BIO and write the data to it, this results in two
   copies of the data and an O(n^2) reading algorithm. There is a new
   function BIO_new_mem_buf() which creates a read only memory BIO from
   an area of memory. Also modified the PKCS#7 routines to use read only
   memory BIOs.

   *Steve Henson*

 * Bugfix: ssl23_get_client_hello did not work properly when called in
   state SSL23_ST_SR_CLNT_HELLO_B, i.e. when the first 7 bytes of
   a SSLv2-compatible client hello for SSLv3 or TLSv1 could be read,
   but a retry condition occurred while trying to read the rest.

   *Bodo Moeller*

 * The PKCS7_ENC_CONTENT_new() function was setting the content type as
   NID_pkcs7_encrypted by default: this was wrong since this should almost
   always be NID_pkcs7_data. Also modified the PKCS7_set_type() to handle
   the encrypted data type: this is a more sensible place to put it and it
   allows the PKCS#12 code to be tidied up that duplicated this
   functionality.

   *Steve Henson*

 * Changed obj_dat.pl script so it takes its input and output files on
   the command line. This should avoid shell escape redirection problems
   under Win32.

   *Steve Henson*

 * Initial support for certificate extension requests, these are included
   in things like Xenroll certificate requests. Included functions to allow
   extensions to be obtained and added.

   *Steve Henson*

 * -crlf option to s_client and s_server for sending newlines as
   CRLF (as required by many protocols).

   *Bodo Moeller*

### Changes between 0.9.3a and 0.9.4  [09 Aug 1999]

 * Install libRSAglue.a when OpenSSL is built with RSAref.

   *Ralf S. Engelschall*

 * A few more `#ifndef NO_FP_API / #endif` pairs for consistency.

   *Andrija Antonijevic <TheAntony2@bigfoot.com>*

 * Fix -startdate and -enddate (which was missing) arguments to 'ca'
   program.

   *Steve Henson*

 * New function DSA_dup_DH, which duplicates DSA parameters/keys as
   DH parameters/keys (q is lost during that conversion, but the resulting
   DH parameters contain its length).

   For 1024-bit p, DSA_generate_parameters followed by DSA_dup_DH is
   much faster than DH_generate_parameters (which creates parameters
   where `p = 2*q + 1`), and also the smaller q makes DH computations
   much more efficient (160-bit exponentiation instead of 1024-bit
   exponentiation); so this provides a convenient way to support DHE
   ciphersuites in SSL/TLS servers (see ssl/ssltest.c).  It is of
   utter importance to use
           SSL_CTX_set_options(s_ctx, SSL_OP_SINGLE_DH_USE);
   or
           SSL_set_options(s_ctx, SSL_OP_SINGLE_DH_USE);
   when such DH parameters are used, because otherwise small subgroup
   attacks may become possible!

   *Bodo Moeller*

 * Avoid memory leak in i2d_DHparams.

   *Bodo Moeller*

 * Allow the -k option to be used more than once in the enc program:
   this allows the same encrypted message to be read by multiple recipients.

   *Steve Henson*

 * New function OBJ_obj2txt(buf, buf_len, a, no_name), this converts
   an ASN1_OBJECT to a text string. If the "no_name" parameter is set then
   it will always use the numerical form of the OID, even if it has a short
   or long name.

   *Steve Henson*

 * Added an extra RSA flag: RSA_FLAG_EXT_PKEY. Previously the rsa_mod_exp
   method only got called if p,q,dmp1,dmq1,iqmp components were present,
   otherwise bn_mod_exp was called. In the case of hardware keys for example
   no private key components need be present and it might store extra data
   in the RSA structure, which cannot be accessed from bn_mod_exp.
   By setting RSA_FLAG_EXT_PKEY rsa_mod_exp will always be called for
   private key operations.

   *Steve Henson*

 * Added support for SPARC Linux.

   *Andy Polyakov*

 * pem_password_cb function type incompatibly changed from
           typedef int pem_password_cb(char *buf, int size, int rwflag);
   to
           ....(char *buf, int size, int rwflag, void *userdata);
   so that applications can pass data to their callbacks:
   The `PEM[_ASN1]_{read,write}...` functions and macros now take an
   additional void * argument, which is just handed through whenever
   the password callback is called.

   *Damien Miller <dmiller@ilogic.com.au>; tiny changes by Bodo Moeller*

   New function SSL_CTX_set_default_passwd_cb_userdata.

   Compatibility note: As many C implementations push function arguments
   onto the stack in reverse order, the new library version is likely to
   interoperate with programs that have been compiled with the old
   pem_password_cb definition (PEM_whatever takes some data that
   happens to be on the stack as its last argument, and the callback
   just ignores this garbage); but there is no guarantee whatsoever that
   this will work.

 * The -DPLATFORM="\"$(PLATFORM)\"" definition and the similar -DCFLAGS=...
   (both in crypto/Makefile.ssl for use by crypto/cversion.c) caused
   problems not only on Windows, but also on some Unix platforms.
   To avoid problematic command lines, these definitions are now in an
   auto-generated file crypto/buildinf.h (created by crypto/Makefile.ssl
   for standard "make" builds, by util/mk1mf.pl for "mk1mf" builds).

   *Bodo Moeller*

 * MIPS III/IV assembler module is reimplemented.

   *Andy Polyakov*

 * More DES library cleanups: remove references to srand/rand and
   delete an unused file.

   *Ulf Möller*

 * Add support for the free Netwide assembler (NASM) under Win32,
   since not many people have MASM (ml) and it can be hard to obtain.
   This is currently experimental but it seems to work OK and pass all
   the tests. Check out INSTALL.W32 for info.

   *Steve Henson*

 * Fix memory leaks in s3_clnt.c: All non-anonymous SSL3/TLS1 connections
   without temporary keys kept an extra copy of the server key,
   and connections with temporary keys did not free everything in case
   of an error.

   *Bodo Moeller*

 * New function RSA_check_key and new openssl rsa option -check
   for verifying the consistency of RSA keys.

   *Ulf Moeller, Bodo Moeller*

 * Various changes to make Win32 compile work:
   1. Casts to avoid "loss of data" warnings in p5_crpt2.c
   2. Change unsigned int to int in b_dump.c to avoid "signed/unsigned
      comparison" warnings.
   3. Add `sk_<TYPE>_sort` to DEF file generator and do make update.

   *Steve Henson*

 * Add a debugging option to PKCS#5 v2 key generation function: when
   you #define DEBUG_PKCS5V2 passwords, salts, iteration counts and
   derived keys are printed to stderr.

   *Steve Henson*

 * Copy the flags in ASN1_STRING_dup().

   *Roman E. Pavlov <pre@mo.msk.ru>*

 * The x509 application mishandled signing requests containing DSA
   keys when the signing key was also DSA and the parameters didn't match.

   It was supposed to omit the parameters when they matched the signing key:
   the verifying software was then supposed to automatically use the CA's
   parameters if they were absent from the end user certificate.

   Omitting parameters is no longer recommended. The test was also
   the wrong way round! This was probably due to unusual behaviour in
   EVP_cmp_parameters() which returns 1 if the parameters match.
   This meant that parameters were omitted when they *didn't* match and
   the certificate was useless. Certificates signed with 'ca' didn't have
   this bug.

   *Steve Henson, reported by Doug Erickson <Doug.Erickson@Part.NET>*

 * Memory leak checking (-DCRYPTO_MDEBUG) had some problems.
   The interface is as follows:
   Applications can use
           CRYPTO_mem_ctrl(CRYPTO_MEM_CHECK_ON) aka MemCheck_start(),
           CRYPTO_mem_ctrl(CRYPTO_MEM_CHECK_OFF) aka MemCheck_stop();
   "off" is now the default.
   The library internally uses
           CRYPTO_mem_ctrl(CRYPTO_MEM_CHECK_DISABLE) aka MemCheck_off(),
           CRYPTO_mem_ctrl(CRYPTO_MEM_CHECK_ENABLE) aka MemCheck_on()
   to disable memory-checking temporarily.

   Some inconsistent states that previously were possible (and were
   even the default) are now avoided.

   -DCRYPTO_MDEBUG_TIME is new and additionally stores the current time
   with each memory chunk allocated; this is occasionally more helpful
   than just having a counter.

   -DCRYPTO_MDEBUG_THREAD is also new and adds the thread ID.

   -DCRYPTO_MDEBUG_ALL enables all of the above, plus any future
   extensions.

   *Bodo Moeller*

 * Introduce "mode" for SSL structures (with defaults in SSL_CTX),
   which largely parallels "options", but is for changing API behaviour,
   whereas "options" are about protocol behaviour.
   Initial "mode" flags are:

   SSL_MODE_ENABLE_PARTIAL_WRITE   Allow SSL_write to report success when
                                   a single record has been written.
   SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER  Don't insist that SSL_write
                                   retries use the same buffer location.
                                   (But all of the contents must be
                                   copied!)

   *Bodo Moeller*

 * Bugfix: SSL_set_options ignored its parameter, only SSL_CTX_set_options
   worked.

 * Fix problems with no-hmac etc.

   *Ulf Möller, pointed out by Brian Wellington <bwelling@tislabs.com>*

 * New functions RSA_get_default_method(), RSA_set_method() and
   RSA_get_method(). These allows replacement of RSA_METHODs without having
   to mess around with the internals of an RSA structure.

   *Steve Henson*

 * Fix memory leaks in DSA_do_sign and DSA_is_prime.
   Also really enable memory leak checks in openssl.c and in some
   test programs.

   *Chad C. Mulligan, Bodo Moeller*

 * Fix a bug in d2i_ASN1_INTEGER() and i2d_ASN1_INTEGER() which can mess
   up the length of negative integers. This has now been simplified to just
   store the length when it is first determined and use it later, rather
   than trying to keep track of where data is copied and updating it to
   point to the end.
   *Steve Henson, reported by Brien Wheeler <bwheeler@authentica-security.com>*

 * Add a new function PKCS7_signatureVerify. This allows the verification
   of a PKCS#7 signature but with the signing certificate passed to the
   function itself. This contrasts with PKCS7_dataVerify which assumes the
   certificate is present in the PKCS#7 structure. This isn't always the
   case: certificates can be omitted from a PKCS#7 structure and be
   distributed by "out of band" means (such as a certificate database).

   *Steve Henson*

 * Complete the `PEM_*` macros with DECLARE_PEM versions to replace the
   function prototypes in pem.h, also change util/mkdef.pl to add the
   necessary function names.

   *Steve Henson*

 * mk1mf.pl (used by Windows builds) did not properly read the
   options set by Configure in the top level Makefile, and Configure
   was not even able to write more than one option correctly.
   Fixed, now "no-idea no-rc5 -DCRYPTO_MDEBUG" etc. works as intended.

   *Bodo Moeller*

 * New functions CONF_load_bio() and CONF_load_fp() to allow a config
   file to be loaded from a BIO or FILE pointer. The BIO version will
   for example allow memory BIOs to contain config info.

   *Steve Henson*

 * New function "CRYPTO_num_locks" that returns CRYPTO_NUM_LOCKS.
   Whoever hopes to achieve shared-library compatibility across versions
   must use this, not the compile-time macro.
   (Exercise 0.9.4: Which is the minimum library version required by
   such programs?)
   Note: All this applies only to multi-threaded programs, others don't
   need locks.

   *Bodo Moeller*

 * Add missing case to s3_clnt.c state machine -- one of the new SSL tests
   through a BIO pair triggered the default case, i.e.
   SSLerr(...,SSL_R_UNKNOWN_STATE).

   *Bodo Moeller*

 * New "BIO pair" concept (crypto/bio/bss_bio.c) so that applications
   can use the SSL library even if none of the specific BIOs is
   appropriate.

   *Bodo Moeller*

 * Fix a bug in i2d_DSAPublicKey() which meant it returned the wrong value
   for the encoded length.

   *Jeon KyoungHo <khjeon@sds.samsung.co.kr>*

 * Add initial documentation of the X509V3 functions.

   *Steve Henson*

 * Add a new pair of functions PEM_write_PKCS8PrivateKey() and
   PEM_write_bio_PKCS8PrivateKey() that are equivalent to
   PEM_write_PrivateKey() and PEM_write_bio_PrivateKey() but use the more
   secure PKCS#8 private key format with a high iteration count.

   *Steve Henson*

 * Fix determination of Perl interpreter: A perl or perl5
   *directory* in $PATH was also accepted as the interpreter.

   *Ralf S. Engelschall*

 * Fix demos/sign/sign.c: well there wasn't anything strictly speaking
   wrong with it but it was very old and did things like calling
   PEM_ASN1_read() directly and used MD5 for the hash not to mention some
   unusual formatting.

   *Steve Henson*

 * Fix demos/selfsign.c: it used obsolete and deleted functions, changed
   to use the new extension code.

   *Steve Henson*

 * Implement the PEM_read/PEM_write functions in crypto/pem/pem_all.c
   with macros. This should make it easier to change their form, add extra
   arguments etc. Fix a few PEM prototypes which didn't have cipher as a
   constant.

   *Steve Henson*

 * Add to configuration table a new entry that can specify an alternative
   name for unistd.h (for pre-POSIX systems); we need this for NeXTstep,
   according to Mark Crispin <MRC@Panda.COM>.

   *Bodo Moeller*

 * DES CBC did not update the IV. Weird.

   *Ben Laurie*
lse
   des_cbc_encrypt does not update the IV, but des_ncbc_encrypt does.
   Changing the behaviour of the former might break existing programs --
   where IV updating is needed, des_ncbc_encrypt can be used.
ndif

 * When bntest is run from "make test" it drives bc to check its
   calculations, as well as internally checking them. If an internal check
   fails, it needs to cause bc to give a non-zero result or make test carries
   on without noticing the failure. Fixed.

   *Ben Laurie*

 * DES library cleanups.

   *Ulf Möller*

 * Add support for PKCS#5 v2.0 PBE algorithms. This will permit PKCS#8 to be
   used with any cipher unlike PKCS#5 v1.5 which can at most handle 64 bit
   ciphers. NOTE: although the key derivation function has been verified
   against some published test vectors it has not been extensively tested
   yet. Added a -v2 "cipher" option to pkcs8 application to allow the use
   of v2.0.

   *Steve Henson*

 * Instead of "mkdir -p", which is not fully portable, use new
   Perl script "util/mkdir-p.pl".

   *Bodo Moeller*

 * Rewrite the way password based encryption (PBE) is handled. It used to
   assume that the ASN1 AlgorithmIdentifier parameter was a PBEParameter
   structure. This was true for the PKCS#5 v1.5 and PKCS#12 PBE algorithms
   but doesn't apply to PKCS#5 v2.0 where it can be something else. Now
   the 'parameter' field of the AlgorithmIdentifier is passed to the
   underlying key generation function so it must do its own ASN1 parsing.
   This has also changed the EVP_PBE_CipherInit() function which now has a
   'parameter' argument instead of literal salt and iteration count values
   and the function EVP_PBE_ALGOR_CipherInit() has been deleted.

   *Steve Henson*

 * Support for PKCS#5 v1.5 compatible password based encryption algorithms
   and PKCS#8 functionality. New 'pkcs8' application linked to openssl.
   Needed to change the PEM_STRING_EVP_PKEY value which was just "PRIVATE
   KEY" because this clashed with PKCS#8 unencrypted string. Since this
   value was just used as a "magic string" and not used directly its
   value doesn't matter.

   *Steve Henson*

 * Introduce some semblance of const correctness to BN. Shame C doesn't
   support mutable.

   *Ben Laurie*

 * "linux-sparc64" configuration (ultrapenguin).

   *Ray Miller <ray.miller@oucs.ox.ac.uk>*
   "linux-sparc" configuration.

   *Christian Forster <fo@hawo.stw.uni-erlangen.de>*

 * config now generates no-xxx options for missing ciphers.

   *Ulf Möller*

 * Support the EBCDIC character set (work in progress).
   File ebcdic.c not yet included because it has a different license.

   *Martin Kraemer <Martin.Kraemer@MchP.Siemens.De>*

 * Support BS2000/OSD-POSIX.

   *Martin Kraemer <Martin.Kraemer@MchP.Siemens.De>*

 * Make callbacks for key generation use `void *` instead of `char *`.

   *Ben Laurie*

 * Make S/MIME samples compile (not yet tested).

   *Ben Laurie*

 * Additional typesafe stacks.

   *Ben Laurie*

 * New configuration variants "bsdi-elf-gcc" (BSD/OS 4.x).

   *Bodo Moeller*

### Changes between 0.9.3 and 0.9.3a  [29 May 1999]

 * New configuration variant "sco5-gcc".

 * Updated some demos.

   *Sean O Riordain, Wade Scholine*

 * Add missing BIO_free at exit of pkcs12 application.

   *Wu Zhigang*

 * Fix memory leak in conf.c.

   *Steve Henson*

 * Updates for Win32 to assembler version of MD5.

   *Steve Henson*

 * Set #! path to perl in `apps/der_chop` to where we found it
   instead of using a fixed path.

   *Bodo Moeller*

 * SHA library changes for irix64-mips4-cc.

   *Andy Polyakov*

 * Improvements for VMS support.

   *Richard Levitte*

### Changes between 0.9.2b and 0.9.3  [24 May 1999]

 * Bignum library bug fix. IRIX 6 passes "make test" now!
   This also avoids the problems with SC4.2 and unpatched SC5.

   *Andy Polyakov <appro@fy.chalmers.se>*

 * New functions sk_num, sk_value and sk_set to replace the previous macros.
   These are required because of the typesafe stack would otherwise break
   existing code. If old code used a structure member which used to be STACK
   and is now STACK_OF (for example cert in a PKCS7_SIGNED structure) with
   sk_num or sk_value it would produce an error because the num, data members
   are not present in STACK_OF. Now it just produces a warning. sk_set
   replaces the old method of assigning a value to sk_value
   (e.g. sk_value(x, i) = y) which the library used in a few cases. Any code
   that does this will no longer work (and should use sk_set instead) but
   this could be regarded as a "questionable" behaviour anyway.

   *Steve Henson*

 * Fix most of the other PKCS#7 bugs. The "experimental" code can now
   correctly handle encrypted S/MIME data.

   *Steve Henson*

 * Change type of various DES function arguments from des_cblock
   (which means, in function argument declarations, pointer to char)
   to des_cblock * (meaning pointer to array with 8 char elements),
   which allows the compiler to do more typechecking; it was like
   that back in SSLeay, but with lots of ugly casts.

   Introduce new type const_des_cblock.

   *Bodo Moeller*

 * Reorganise the PKCS#7 library and get rid of some of the more obvious
   problems: find RecipientInfo structure that matches recipient certificate
   and initialise the ASN1 structures properly based on passed cipher.

   *Steve Henson*

 * Belatedly make the BN tests actually check the results.

   *Ben Laurie*

 * Fix the encoding and decoding of negative ASN1 INTEGERS and conversion
   to and from BNs: it was completely broken. New compilation option
   NEG_PUBKEY_BUG to allow for some broken certificates that encode public
   key elements as negative integers.

   *Steve Henson*

 * Reorganize and speed up MD5.

   *Andy Polyakov <appro@fy.chalmers.se>*

 * VMS support.

   *Richard Levitte <richard@levitte.org>*

 * New option -out to asn1parse to allow the parsed structure to be
   output to a file. This is most useful when combined with the -strparse
   option to examine the output of things like OCTET STRINGS.

   *Steve Henson*

 * Make SSL library a little more fool-proof by not requiring any longer
   that `SSL_set_{accept,connect}_state` be called before
   `SSL_{accept,connect}` may be used (`SSL_set_..._state` is omitted
   in many applications because usually everything *appeared* to work as
   intended anyway -- now it really works as intended).

   *Bodo Moeller*

 * Move openssl.cnf out of lib/.

   *Ulf Möller*

 * Fix various things to let OpenSSL even pass "egcc -pipe -O2 -Wall
   -Wshadow -Wpointer-arith -Wcast-align -Wmissing-prototypes
   -Wmissing-declarations -Wnested-externs -Winline" with EGCS 1.1.2+

   *Ralf S. Engelschall*

 * Various fixes to the EVP and PKCS#7 code. It may now be able to
   handle PKCS#7 enveloped data properly.

   *Sebastian Akerman <sak@parallelconsulting.com>, modified by Steve*

 * Create a duplicate of the SSL_CTX's CERT in SSL_new instead of
   copying pointers.  The cert_st handling is changed by this in
   various ways (and thus what used to be known as ctx->default_cert
   is now called ctx->cert, since we don't resort to `s->ctx->[default_]cert`
   any longer when s->cert does not give us what we need).
   ssl_cert_instantiate becomes obsolete by this change.
   As soon as we've got the new code right (possibly it already is?),
   we have solved a couple of bugs of the earlier code where s->cert
   was used as if it could not have been shared with other SSL structures.

   Note that using the SSL API in certain dirty ways now will result
   in different behaviour than observed with earlier library versions:
   Changing settings for an `SSL_CTX *ctx` after having done s = SSL_new(ctx)
   does not influence s as it used to.

   In order to clean up things more thoroughly, inside SSL_SESSION
   we don't use CERT any longer, but a new structure SESS_CERT
   that holds per-session data (if available); currently, this is
   the peer's certificate chain and, for clients, the server's certificate
   and temporary key.  CERT holds only those values that can have
   meaningful defaults in an SSL_CTX.

   *Bodo Moeller*

 * New function X509V3_EXT_i2d() to create an X509_EXTENSION structure
   from the internal representation. Various PKCS#7 fixes: remove some
   evil casts and set the enc_dig_alg field properly based on the signing
   key type.

   *Steve Henson*

 * Allow PKCS#12 password to be set from the command line or the
   environment. Let 'ca' get its config file name from the environment
   variables "OPENSSL_CONF" or "SSLEAY_CONF" (for consistency with 'req'
   and 'x509').

   *Steve Henson*

 * Allow certificate policies extension to use an IA5STRING for the
   organization field. This is contrary to the PKIX definition but
   VeriSign uses it and IE5 only recognises this form. Document 'x509'
   extension option.

   *Steve Henson*

 * Add PEDANTIC compiler flag to allow compilation with gcc -pedantic,
   without disallowing inline assembler and the like for non-pedantic builds.

   *Ben Laurie*

 * Support Borland C++ builder.

   *Janez Jere <jj@void.si>, modified by Ulf Möller*

 * Support Mingw32.

   *Ulf Möller*

 * SHA-1 cleanups and performance enhancements.

   *Andy Polyakov <appro@fy.chalmers.se>*

 * Sparc v8plus assembler for the bignum library.

   *Andy Polyakov <appro@fy.chalmers.se>*

 * Accept any -xxx and +xxx compiler options in Configure.

   *Ulf Möller*

 * Update HPUX configuration.

   *Anonymous*

 * Add missing `sk_<type>_unshift()` function to safestack.h

   *Ralf S. Engelschall*

 * New function SSL_CTX_use_certificate_chain_file that sets the
   "extra_cert"s in addition to the certificate.  (This makes sense
   only for "PEM" format files, as chains as a whole are not
   DER-encoded.)

   *Bodo Moeller*

 * Support verify_depth from the SSL API.
   x509_vfy.c had what can be considered an off-by-one-error:
   Its depth (which was not part of the external interface)
   was actually counting the number of certificates in a chain;
   now it really counts the depth.

   *Bodo Moeller*

 * Bugfix in crypto/x509/x509_cmp.c: The SSLerr macro was used
   instead of X509err, which often resulted in confusing error
   messages since the error codes are not globally unique
   (e.g. an alleged error in ssl3_accept when a certificate
   didn't match the private key).

 * New function SSL_CTX_set_session_id_context that allows to set a default
   value (so that you don't need SSL_set_session_id_context for each
   connection using the SSL_CTX).

   *Bodo Moeller*

 * OAEP decoding bug fix.

   *Ulf Möller*

 * Support INSTALL_PREFIX for package builders, as proposed by
   David Harris.

   *Bodo Moeller*

 * New Configure options "threads" and "no-threads".  For systems
   where the proper compiler options are known (currently Solaris
   and Linux), "threads" is the default.

   *Bodo Moeller*

 * New script util/mklink.pl as a faster substitute for util/mklink.sh.

   *Bodo Moeller*

 * Install various scripts to $(OPENSSLDIR)/misc, not to
   $(INSTALLTOP)/bin -- they shouldn't clutter directories
   such as /usr/local/bin.

   *Bodo Moeller*

 * "make linux-shared" to build shared libraries.

   *Niels Poppe <niels@netbox.org>*

 * New Configure option `no-<cipher>` (rsa, idea, rc5, ...).

   *Ulf Möller*

 * Add the PKCS#12 API documentation to openssl.txt. Preliminary support for
   extension adding in x509 utility.

   *Steve Henson*

 * Remove NOPROTO sections and error code comments.

   *Ulf Möller*

 * Partial rewrite of the DEF file generator to now parse the ANSI
   prototypes.

   *Steve Henson*

 * New Configure options --prefix=DIR and --openssldir=DIR.

   *Ulf Möller*

 * Complete rewrite of the error code script(s). It is all now handled
   by one script at the top level which handles error code gathering,
   header rewriting and C source file generation. It should be much better
   than the old method: it now uses a modified version of Ulf's parser to
   read the ANSI prototypes in all header files (thus the old K&R definitions
   aren't needed for error creation any more) and do a better job of
   translating function codes into names. The old 'ASN1 error code embedded
   in a comment' is no longer necessary and it doesn't use .err files which
   have now been deleted. Also the error code call doesn't have to appear all
   on one line (which resulted in some large lines...).

   *Steve Henson*

 * Change #include filenames from `<foo.h>` to `<openssl/foo.h>`.

   *Bodo Moeller*

 * Change behaviour of ssl2_read when facing length-0 packets: Don't return
   0 (which usually indicates a closed connection), but continue reading.

   *Bodo Moeller*

 * Fix some race conditions.

   *Bodo Moeller*

 * Add support for CRL distribution points extension. Add Certificate
   Policies and CRL distribution points documentation.

   *Steve Henson*

 * Move the autogenerated header file parts to crypto/opensslconf.h.

   *Ulf Möller*

 * Fix new 56-bit DES export ciphersuites: they were using 7 bytes instead of
   8 of keying material. Merlin has also confirmed interop with this fix
   between OpenSSL and Baltimore C/SSL 2.0 and J/SSL 2.0.

   *Merlin Hughes <merlin@baltimore.ie>*

 * Fix lots of warnings.

   *Richard Levitte <levitte@stacken.kth.se>*

 * In add_cert_dir() in crypto/x509/by_dir.c, break out of the loop if
   the directory spec didn't end with a LIST_SEPARATOR_CHAR.

   *Richard Levitte <levitte@stacken.kth.se>*

 * Fix problems with sizeof(long) == 8.

   *Andy Polyakov <appro@fy.chalmers.se>*

 * Change functions to ANSI C.

   *Ulf Möller*

 * Fix typos in error codes.

   *Martin Kraemer <Martin.Kraemer@MchP.Siemens.De>, Ulf Möller*

 * Remove defunct assembler files from Configure.

   *Ulf Möller*

 * SPARC v8 assembler BIGNUM implementation.

   *Andy Polyakov <appro@fy.chalmers.se>*

 * Support for Certificate Policies extension: both print and set.
   Various additions to support the r2i method this uses.

   *Steve Henson*

 * A lot of constification, and fix a bug in X509_NAME_oneline() that could
   return a const string when you are expecting an allocated buffer.

   *Ben Laurie*

 * Add support for ASN1 types UTF8String and VISIBLESTRING, also the CHOICE
   types DirectoryString and DisplayText.

   *Steve Henson*

 * Add code to allow r2i extensions to access the configuration database,
   add an LHASH database driver and add several ctx helper functions.

   *Steve Henson*

 * Fix an evil bug in bn_expand2() which caused various BN functions to
   fail when they extended the size of a BIGNUM.

   *Steve Henson*

 * Various utility functions to handle SXNet extension. Modify mkdef.pl to
   support typesafe stack.

   *Steve Henson*

 * Fix typo in SSL_[gs]et_options().

   *Nils Frostberg <nils@medcom.se>*

 * Delete various functions and files that belonged to the (now obsolete)
   old X509V3 handling code.

   *Steve Henson*

 * New Configure option "rsaref".

   *Ulf Möller*

 * Don't auto-generate pem.h.

   *Bodo Moeller*

 * Introduce type-safe ASN.1 SETs.

   *Ben Laurie*

 * Convert various additional casted stacks to type-safe STACK_OF() variants.

   *Ben Laurie, Ralf S. Engelschall, Steve Henson*

 * Introduce type-safe STACKs. This will almost certainly break lots of code
   that links with OpenSSL (well at least cause lots of warnings), but fear
   not: the conversion is trivial, and it eliminates loads of evil casts. A
   few STACKed things have been converted already. Feel free to convert more.
   In the fullness of time, I'll do away with the STACK type altogether.

   *Ben Laurie*

 * Add `openssl ca -revoke <certfile>` facility which revokes a certificate
   specified in `<certfile>` by updating the entry in the index.txt file.
   This way one no longer has to edit the index.txt file manually for
   revoking a certificate. The -revoke option does the gory details now.

   *Massimiliano Pala <madwolf@openca.org>, Ralf S. Engelschall*

 * Fix `openssl crl -noout -text` combination where `-noout` killed the
   `-text` option at all and this way the `-noout -text` combination was
   inconsistent in `openssl crl` with the friends in `openssl x509|rsa|dsa`.

   *Ralf S. Engelschall*

 * Make sure a corresponding plain text error message exists for the
   X509_V_ERR_CERT_REVOKED/23 error number which can occur when a
   verify callback function determined that a certificate was revoked.

   *Ralf S. Engelschall*

 * Bugfix: In test/testenc, don't test `openssl <cipher>` for
   ciphers that were excluded, e.g. by -DNO_IDEA.  Also, test
   all available ciphers including rc5, which was forgotten until now.
   In order to let the testing shell script know which algorithms
   are available, a new (up to now undocumented) command
   `openssl list-cipher-commands` is used.

   *Bodo Moeller*

 * Bugfix: s_client occasionally would sleep in select() when
   it should have checked SSL_pending() first.

   *Bodo Moeller*

 * New functions DSA_do_sign and DSA_do_verify to provide access to
   the raw DSA values prior to ASN.1 encoding.

   *Ulf Möller*

 * Tweaks to Configure

   *Niels Poppe <niels@netbox.org>*

 * Add support for PKCS#5 v2.0 ASN1 PBES2 structures. No other support,
   yet...

   *Steve Henson*

 * New variables $(RANLIB) and $(PERL) in the Makefiles.

   *Ulf Möller*

 * New config option to avoid instructions that are illegal on the 80386.
   The default code is faster, but requires at least a 486.

   *Ulf Möller*

 * Got rid of old SSL2_CLIENT_VERSION (inconsistently used) and
   SSL2_SERVER_VERSION (not used at all) macros, which are now the
   same as SSL2_VERSION anyway.

   *Bodo Moeller*

 * New "-showcerts" option for s_client.

   *Bodo Moeller*

 * Still more PKCS#12 integration. Add pkcs12 application to openssl
   application. Various cleanups and fixes.

   *Steve Henson*

 * More PKCS#12 integration. Add new pkcs12 directory with Makefile.ssl and
   modify error routines to work internally. Add error codes and PBE init
   to library startup routines.

   *Steve Henson*

 * Further PKCS#12 integration. Added password based encryption, PKCS#8 and
   packing functions to asn1 and evp. Changed function names and error
   codes along the way.

   *Steve Henson*

 * PKCS12 integration: and so it begins... First of several patches to
   slowly integrate PKCS#12 functionality into OpenSSL. Add PKCS#12
   objects to objects.h

   *Steve Henson*

 * Add a new 'indent' option to some X509V3 extension code. Initial ASN1
   and display support for Thawte strong extranet extension.

   *Steve Henson*

 * Add LinuxPPC support.

   *Jeff Dubrule <igor@pobox.org>*

 * Get rid of redundant BN file bn_mulw.c, and rename bn_div64 to
   bn_div_words in alpha.s.

   *Hannes Reinecke <H.Reinecke@hw.ac.uk> and Ben Laurie*

 * Make sure the RSA OAEP test is skipped under -DRSAref because
   OAEP isn't supported when OpenSSL is built with RSAref.

   *Ulf Moeller <ulf@fitug.de>*

 * Move definitions of IS_SET/IS_SEQUENCE inside crypto/asn1/asn1.h
   so they no longer are missing under -DNOPROTO.

   *Soren S. Jorvang <soren@t.dk>*

### Changes between 0.9.1c and 0.9.2b  [22 Mar 1999]

 * Make SSL_get_peer_cert_chain() work in servers. Unfortunately, it still
   doesn't work when the session is reused. Coming soon!

   *Ben Laurie*

 * Fix a security hole, that allows sessions to be reused in the wrong
   context thus bypassing client cert protection! All software that uses
   client certs and session caches in multiple contexts NEEDS PATCHING to
   allow session reuse! A fuller solution is in the works.

   *Ben Laurie, problem pointed out by Holger Reif, Bodo Moeller (and ???)*

 * Some more source tree cleanups (removed obsolete files
   crypto/bf/asm/bf586.pl, test/test.txt and crypto/sha/asm/f.s; changed
   permission on "config" script to be executable) and a fix for the INSTALL
   document.

   *Ulf Moeller <ulf@fitug.de>*

 * Remove some legacy and erroneous uses of malloc, free instead of
   Malloc, Free.

   *Lennart Bang <lob@netstream.se>, with minor changes by Steve*

 * Make rsa_oaep_test return non-zero on error.

   *Ulf Moeller <ulf@fitug.de>*

 * Add support for native Solaris shared libraries. Configure
   solaris-sparc-sc4-pic, make, then run shlib/solaris-sc4.sh. It'd be nice
   if someone would make that last step automatic.

   *Matthias Loepfe <Matthias.Loepfe@AdNovum.CH>*

 * ctx_size was not built with the right compiler during "make links". Fixed.

   *Ben Laurie*

 * Change the meaning of 'ALL' in the cipher list. It now means "everything
   except NULL ciphers". This means the default cipher list will no longer
   enable NULL ciphers. They need to be specifically enabled e.g. with
   the string "DEFAULT:eNULL".

   *Steve Henson*

 * Fix to RSA private encryption routines: if p < q then it would
   occasionally produce an invalid result. This will only happen with
   externally generated keys because OpenSSL (and SSLeay) ensure p > q.

   *Steve Henson*

 * Be less restrictive and allow also `perl util/perlpath.pl
   /path/to/bin/perl` in addition to `perl util/perlpath.pl /path/to/bin`,
   because this way one can also use an interpreter named `perl5` (which is
   usually the name of Perl 5.xxx on platforms where an Perl 4.x is still
   installed as `perl`).

   *Matthias Loepfe <Matthias.Loepfe@adnovum.ch>*

 * Let util/clean-depend.pl work also with older Perl 5.00x versions.

   *Matthias Loepfe <Matthias.Loepfe@adnovum.ch>*

 * Fix Makefile.org so CC,CFLAG etc are passed to 'make links' add
   advapi32.lib to Win32 build and change the pem test comparison
   to fc.exe (thanks to Ulrich Kroener <kroneru@yahoo.com> for the
   suggestion). Fix misplaced ASNI prototypes and declarations in evp.h
   and crypto/des/ede_cbcm_enc.c.

   *Steve Henson*

 * DES quad checksum was broken on big-endian architectures. Fixed.

   *Ben Laurie*

 * Comment out two functions in bio.h that aren't implemented. Fix up the
   Win32 test batch file so it (might) work again. The Win32 test batch file
   is horrible: I feel ill....

   *Steve Henson*

 * Move various #ifdefs around so NO_SYSLOG, NO_DIRENT etc are now selected
   in e_os.h. Audit of header files to check ANSI and non ANSI
   sections: 10 functions were absent from non ANSI section and not exported
   from Windows DLLs. Fixed up libeay.num for new functions.

   *Steve Henson*

 * Make `openssl version` output lines consistent.

   *Ralf S. Engelschall*

 * Fix Win32 symbol export lists for BIO functions: Added
   BIO_get_ex_new_index, BIO_get_ex_num, BIO_get_ex_data and BIO_set_ex_data
   to ms/libeay{16,32}.def.

   *Ralf S. Engelschall*

 * Second round of fixing the OpenSSL perl/ stuff. It now at least compiled
   fine under Unix and passes some trivial tests I've now added. But the
   whole stuff is horribly incomplete, so a README.1ST with a disclaimer was
   added to make sure no one expects that this stuff really works in the
   OpenSSL 0.9.2 release.  Additionally I've started to clean the XS sources
   up and fixed a few little bugs and inconsistencies in OpenSSL.{pm,xs} and
   openssl_bio.xs.

   *Ralf S. Engelschall*

 * Fix the generation of two part addresses in perl.

   *Kenji Miyake <kenji@miyake.org>, integrated by Ben Laurie*

 * Add config entry for Linux on MIPS.

   *John Tobey <jtobey@channel1.com>*

 * Make links whenever Configure is run, unless we are on Windoze.

   *Ben Laurie*

 * Permit extensions to be added to CRLs using crl_section in openssl.cnf.
   Currently only issuerAltName and AuthorityKeyIdentifier make any sense
   in CRLs.

   *Steve Henson*

 * Add a useful kludge to allow package maintainers to specify compiler and
   other platforms details on the command line without having to patch the
   Configure script every time: One now can use
   `perl Configure <id>:<details>`,
   i.e. platform ids are allowed to have details appended
   to them (separated by colons). This is treated as there would be a static
   pre-configured entry in Configure's %table under key `<id>` with value
   `<details>` and `perl Configure <id>` is called.  So, when you want to
   perform a quick test-compile under FreeBSD 3.1 with pgcc and without
   assembler stuff you can use `perl Configure "FreeBSD-elf:pgcc:-O6:::"`
   now, which overrides the FreeBSD-elf entry on-the-fly.

   *Ralf S. Engelschall*

 * Disable new TLS1 ciphersuites by default: they aren't official yet.

   *Ben Laurie*

 * Allow DSO flags like -fpic, -fPIC, -KPIC etc. to be specified
   on the `perl Configure ...` command line. This way one can compile
   OpenSSL libraries with Position Independent Code (PIC) which is needed
   for linking it into DSOs.

   *Ralf S. Engelschall*

 * Remarkably, export ciphers were totally broken and no-one had noticed!
   Fixed.

   *Ben Laurie*

 * Cleaned up the LICENSE document: The official contact for any license
   questions now is the OpenSSL core team under openssl-core@openssl.org.
   And add a paragraph about the dual-license situation to make sure people
   recognize that _BOTH_ the OpenSSL license _AND_ the SSLeay license apply
   to the OpenSSL toolkit.

   *Ralf S. Engelschall*

 * General source tree makefile cleanups: Made `making xxx in yyy...`
   display consistent in the source tree and replaced `/bin/rm` by `rm`.
   Additionally cleaned up the `make links` target: Remove unnecessary
   semicolons, subsequent redundant removes, inline point.sh into mklink.sh
   to speed processing and no longer clutter the display with confusing
   stuff. Instead only the actually done links are displayed.

   *Ralf S. Engelschall*

 * Permit null encryption ciphersuites, used for authentication only. It used
   to be necessary to set the preprocessor define SSL_ALLOW_ENULL to do this.
   It is now necessary to set SSL_FORBID_ENULL to prevent the use of null
   encryption.

   *Ben Laurie*

 * Add a bunch of fixes to the PKCS#7 stuff. It used to sometimes reorder
   signed attributes when verifying signatures (this would break them),
   the detached data encoding was wrong and public keys obtained using
   X509_get_pubkey() weren't freed.

   *Steve Henson*

 * Add text documentation for the BUFFER functions. Also added a work around
   to a Win95 console bug. This was triggered by the password read stuff: the
   last character typed gets carried over to the next fread(). If you were
   generating a new cert request using 'req' for example then the last
   character of the passphrase would be CR which would then enter the first
   field as blank.

   *Steve Henson*

 * Added the new 'Includes OpenSSL Cryptography Software' button as
   doc/openssl_button.{gif,html} which is similar in style to the old SSLeay
   button and can be used by applications based on OpenSSL to show the
   relationship to the OpenSSL project.

   *Ralf S. Engelschall*

 * Remove confusing variables in function signatures in files
   ssl/ssl_lib.c and ssl/ssl.h.

   *Lennart Bong <lob@kulthea.stacken.kth.se>*

 * Don't install bss_file.c under PREFIX/include/

   *Lennart Bong <lob@kulthea.stacken.kth.se>*

 * Get the Win32 compile working again. Modify mkdef.pl so it can handle
   functions that return function pointers and has support for NT specific
   stuff. Fix mk1mf.pl and VC-32.pl to support NT differences also. Various
   #ifdef WIN32 and WINNTs sprinkled about the place and some changes from
   unsigned to signed types: this was killing the Win32 compile.

   *Steve Henson*

 * Add new certificate file to stack functions,
   SSL_add_dir_cert_subjects_to_stack() and
   SSL_add_file_cert_subjects_to_stack().  These largely supplant
   SSL_load_client_CA_file(), and can be used to add multiple certs easily
   to a stack (usually this is then handed to SSL_CTX_set_client_CA_list()).
   This means that Apache-SSL and similar packages don't have to mess around
   to add as many CAs as they want to the preferred list.

   *Ben Laurie*

 * Experiment with doxygen documentation. Currently only partially applied to
   ssl/ssl_lib.c.
   See <http://www.stack.nl/~dimitri/doxygen/index.html>, and run doxygen with
   openssl.doxy as the configuration file.

   *Ben Laurie*

 * Get rid of remaining C++-style comments which strict C compilers hate.

   *Ralf S. Engelschall, pointed out by Carlos Amengual*

 * Changed BN_RECURSION in bn_mont.c to BN_RECURSION_MONT so it is not
   compiled in by default: it has problems with large keys.

   *Steve Henson*

 * Add a bunch of SSL_xxx() functions for configuring the temporary RSA and
   DH private keys and/or callback functions which directly correspond to
   their SSL_CTX_xxx() counterparts but work on a per-connection basis. This
   is needed for applications which have to configure certificates on a
   per-connection basis (e.g. Apache+mod_ssl) instead of a per-context basis
   (e.g. s_server).
      For the RSA certificate situation is makes no difference, but
   for the DSA certificate situation this fixes the "no shared cipher"
   problem where the OpenSSL cipher selection procedure failed because the
   temporary keys were not overtaken from the context and the API provided
   no way to reconfigure them.
      The new functions now let applications reconfigure the stuff and they
   are in detail: SSL_need_tmp_RSA, SSL_set_tmp_rsa, SSL_set_tmp_dh,
   SSL_set_tmp_rsa_callback and SSL_set_tmp_dh_callback.  Additionally a new
   non-public-API function ssl_cert_instantiate() is used as a helper
   function and also to reduce code redundancy inside ssl_rsa.c.

   *Ralf S. Engelschall*

 * Move s_server -dcert and -dkey options out of the undocumented feature
   area because they are useful for the DSA situation and should be
   recognized by the users.

   *Ralf S. Engelschall*

 * Fix the cipher decision scheme for export ciphers: the export bits are
   *not* within SSL_MKEY_MASK or SSL_AUTH_MASK, they are within
   SSL_EXP_MASK.  So, the original variable has to be used instead of the
   already masked variable.

   *Richard Levitte <levitte@stacken.kth.se>*

 * Fix `port` variable from `int` to `unsigned int` in crypto/bio/b_sock.c

   *Richard Levitte <levitte@stacken.kth.se>*

 * Change type of another md_len variable in pk7_doit.c:PKCS7_dataFinal()
   from `int` to `unsigned int` because it is a length and initialized by
   EVP_DigestFinal() which expects an `unsigned int *`.

   *Richard Levitte <levitte@stacken.kth.se>*

 * Don't hard-code path to Perl interpreter on shebang line of Configure
   script. Instead use the usual Shell->Perl transition trick.

   *Ralf S. Engelschall*

 * Make `openssl x509 -noout -modulus`' functional also for DSA certificates
   (in addition to RSA certificates) to match the behaviour of `openssl dsa
   -noout -modulus` as it's already the case for `openssl rsa -noout
   -modulus`.  For RSA the -modulus is the real "modulus" while for DSA
   currently the public key is printed (a decision which was already done by
   `openssl dsa -modulus` in the past) which serves a similar purpose.
   Additionally the NO_RSA no longer completely removes the whole -modulus
   option; it now only avoids using the RSA stuff. Same applies to NO_DSA
   now, too.

   *Ralf S.  Engelschall*

 * Add Arne Ansper's reliable BIO - this is an encrypted, block-digested
   BIO. See the source (crypto/evp/bio_ok.c) for more info.

   *Arne Ansper <arne@ats.cyber.ee>*

 * Dump the old yucky req code that tried (and failed) to allow raw OIDs
   to be added. Now both 'req' and 'ca' can use new objects defined in the
   config file.

   *Steve Henson*

 * Add cool BIO that does syslog (or event log on NT).

   *Arne Ansper <arne@ats.cyber.ee>, integrated by Ben Laurie*

 * Add support for new TLS ciphersuites, TLS_RSA_EXPORT56_WITH_RC4_56_MD5,
   TLS_RSA_EXPORT56_WITH_RC2_CBC_56_MD5 and
   TLS_RSA_EXPORT56_WITH_DES_CBC_SHA, as specified in "56-bit Export Cipher
   Suites For TLS", draft-ietf-tls-56-bit-ciphersuites-00.txt.

   *Ben Laurie*

 * Add preliminary config info for new extension code.

   *Steve Henson*

 * Make RSA_NO_PADDING really use no padding.

   *Ulf Moeller <ulf@fitug.de>*

 * Generate errors when private/public key check is done.

   *Ben Laurie*

 * Overhaul for 'crl' utility. New function X509_CRL_print. Partial support
   for some CRL extensions and new objects added.

   *Steve Henson*

 * Really fix the ASN1 IMPLICIT bug this time... Partial support for private
   key usage extension and fuller support for authority key id.

   *Steve Henson*

 * Add OAEP encryption for the OpenSSL crypto library. OAEP is the improved
   padding method for RSA, which is recommended for new applications in PKCS
   #1 v2.0 (RFC 2437, October 1998).
   OAEP (Optimal Asymmetric Encryption Padding) has better theoretical
   foundations than the ad-hoc padding used in PKCS #1 v1.5. It is secure
   against Bleichbacher's attack on RSA.
   *Ulf Moeller <ulf@fitug.de>, reformatted, corrected and integrated by
   Ben Laurie*

 * Updates to the new SSL compression code

   *Eric A. Young, (from changes to C2Net SSLeay, integrated by Mark Cox)*

 * Fix so that the version number in the master secret, when passed
   via RSA, checks that if TLS was proposed, but we roll back to SSLv3
   (because the server will not accept higher), that the version number
   is 0x03,0x01, not 0x03,0x00

   *Eric A. Young, (from changes to C2Net SSLeay, integrated by Mark Cox)*

 * Run extensive memory leak checks on SSL commands. Fixed *lots* of memory
   leaks in `ssl/` relating to new `X509_get_pubkey()` behaviour. Also fixes
   in `apps/` and an unrelated leak in `crypto/dsa/dsa_vrf.c`.

   *Steve Henson*

 * Support for RAW extensions where an arbitrary extension can be
   created by including its DER encoding. See `apps/openssl.cnf` for
   an example.

   *Steve Henson*

 * Make sure latest Perl versions don't interpret some generated C array
   code as Perl array code in the crypto/err/err_genc.pl script.

   *Lars Weber <3weber@informatik.uni-hamburg.de>*

 * Modify ms/do_ms.bat to not generate assembly language makefiles since
   not many people have the assembler. Various Win32 compilation fixes and
   update to the INSTALL.W32 file with (hopefully) more accurate Win32
   build instructions.

   *Steve Henson*

 * Modify configure script 'Configure' to automatically create crypto/date.h
   file under Win32 and also build pem.h from pem.org. New script
   util/mkfiles.pl to create the MINFO file on environments that can't do a
   'make files': perl util/mkfiles.pl >MINFO should work.

   *Steve Henson*

 * Major rework of DES function declarations, in the pursuit of correctness
   and purity. As a result, many evil casts evaporated, and some weirdness,
   too. You may find this causes warnings in your code. Zapping your evil
   casts will probably fix them. Mostly.

   *Ben Laurie*

 * Fix for a typo in asn1.h. Bug fix to object creation script
   obj_dat.pl. It considered a zero in an object definition to mean
   "end of object": none of the objects in objects.h have any zeros
   so it wasn't spotted.

   *Steve Henson, reported by Erwann ABALEA <eabalea@certplus.com>*

 * Add support for Triple DES Cipher Block Chaining with Output Feedback
   Masking (CBCM). In the absence of test vectors, the best I have been able
   to do is check that the decrypt undoes the encrypt, so far. Send me test
   vectors if you have them.

   *Ben Laurie*

 * Correct calculation of key length for export ciphers (too much space was
   allocated for null ciphers). This has not been tested!

   *Ben Laurie*

 * Modifications to the mkdef.pl for Win32 DEF file creation. The usage
   message is now correct (it understands "crypto" and "ssl" on its
   command line). There is also now an "update" option. This will update
   the util/ssleay.num and util/libeay.num files with any new functions.
   If you do a:
   perl util/mkdef.pl crypto ssl update
   it will update them.

   *Steve Henson*

 * Overhauled the Perl interface:
   - ported BN stuff to OpenSSL's different BN library
   - made the perl/ source tree CVS-aware
   - renamed the package from SSLeay to OpenSSL (the files still contain
     their history because I've copied them in the repository)
   - removed obsolete files (the test scripts will be replaced
     by better Test::Harness variants in the future)

   *Ralf S. Engelschall*

 * First cut for a very conservative source tree cleanup:
   1. merge various obsolete readme texts into doc/ssleay.txt
   where we collect the old documents and readme texts.
   2. remove the first part of files where I'm already sure that we no
   longer need them because of three reasons: either they are just temporary
   files which were left by Eric or they are preserved original files where
   I've verified that the diff is also available in the CVS via "cvs diff
   -rSSLeay_0_8_1b" or they were renamed (as it was definitely the case for
   the crypto/md/ stuff).

   *Ralf S. Engelschall*

 * More extension code. Incomplete support for subject and issuer alt
   name, issuer and authority key id. Change the i2v function parameters
   and add an extra 'crl' parameter in the X509V3_CTX structure: guess
   what that's for :-) Fix to ASN1 macro which messed up
   IMPLICIT tag and add f_enum.c which adds a2i, i2a for ENUMERATED.

   *Steve Henson*

 * Preliminary support for ENUMERATED type. This is largely copied from the
   INTEGER code.

   *Steve Henson*

 * Add new function, EVP_MD_CTX_copy() to replace frequent use of memcpy.

   *Eric A. Young, (from changes to C2Net SSLeay, integrated by Mark Cox)*

 * Make sure `make rehash` target really finds the `openssl` program.

   *Ralf S. Engelschall, Matthias Loepfe <Matthias.Loepfe@adnovum.ch>*

 * Squeeze another 7% of speed out of MD5 assembler, at least on a P2. I'd
   like to hear about it if this slows down other processors.

   *Ben Laurie*

 * Add CygWin32 platform information to Configure script.

   *Alan Batie <batie@aahz.jf.intel.com>*

 * Fixed ms/32all.bat script: `no_asm` -> `no-asm`

   *Rainer W. Gerling <gerling@mpg-gv.mpg.de>*

 * New program nseq to manipulate netscape certificate sequences

   *Steve Henson*

 * Modify crl2pkcs7 so it supports multiple -certfile arguments. Fix a
   few typos.

   *Steve Henson*

 * Fixes to BN code.  Previously the default was to define BN_RECURSION
   but the BN code had some problems that would cause failures when
   doing certificate verification and some other functions.

   *Eric A. Young, (from changes to C2Net SSLeay, integrated by Mark Cox)*

 * Add ASN1 and PEM code to support netscape certificate sequences.

   *Steve Henson*

 * Add ASN1 and PEM code to support netscape certificate sequences.

   *Steve Henson*

 * Add several PKIX and private extended key usage OIDs.

   *Steve Henson*

 * Modify the 'ca' program to handle the new extension code. Modify
   openssl.cnf for new extension format, add comments.

   *Steve Henson*

 * More X509 V3 changes. Fix typo in v3_bitstr.c. Add support to 'req'
   and add a sample to openssl.cnf so req -x509 now adds appropriate
   CA extensions.

   *Steve Henson*

 * Continued X509 V3 changes. Add to other makefiles, integrate with the
   error code, add initial support to X509_print() and x509 application.

   *Steve Henson*

 * Takes a deep breath and start adding X509 V3 extension support code. Add
   files in crypto/x509v3. Move original stuff to crypto/x509v3/old. All this
   stuff is currently isolated and isn't even compiled yet.

   *Steve Henson*

 * Continuing patches for GeneralizedTime. Fix up certificate and CRL
   ASN1 to use ASN1_TIME and modify print routines to use ASN1_TIME_print.
   Removed the versions check from X509 routines when loading extensions:
   this allows certain broken certificates that don't set the version
   properly to be processed.

   *Steve Henson*

 * Deal with irritating shit to do with dependencies, in YAAHW (Yet Another
   Ad Hoc Way) - Makefile.ssls now all contain local dependencies, which
   can still be regenerated with "make depend".

   *Ben Laurie*

 * Spelling mistake in C version of CAST-128.

   *Ben Laurie, reported by Jeremy Hylton <jeremy@cnri.reston.va.us>*

 * Changes to the error generation code. The perl script err-code.pl
   now reads in the old error codes and retains the old numbers, only
   adding new ones if necessary. It also only changes the .err files if new
   codes are added. The makefiles have been modified to only insert errors
   when needed (to avoid needlessly modifying header files). This is done
   by only inserting errors if the .err file is newer than the auto generated
   C file. To rebuild all the error codes from scratch (the old behaviour)
   either modify crypto/Makefile.ssl to pass the -regen flag to err_code.pl
   or delete all the .err files.

   *Steve Henson*

 * CAST-128 was incorrectly implemented for short keys. The C version has
   been fixed, but is untested. The assembler versions are also fixed, but
   new assembler HAS NOT BEEN GENERATED FOR WIN32 - the Makefile needs fixing
   to regenerate it if needed.
   *Ben Laurie, reported (with fix for C version) by Jun-ichiro itojun
    Hagino <itojun@kame.net>*

 * File was opened incorrectly in randfile.c.

   *Ulf Möller <ulf@fitug.de>*

 * Beginning of support for GeneralizedTime. d2i, i2d, check and print
   functions. Also ASN1_TIME suite which is a CHOICE of UTCTime or
   GeneralizedTime. ASN1_TIME is the proper type used in certificates et
   al: it's just almost always a UTCTime. Note this patch adds new error
   codes so do a "make errors" if there are problems.

   *Steve Henson*

 * Correct Linux 1 recognition in config.

   *Ulf Möller <ulf@fitug.de>*

 * Remove pointless MD5 hash when using DSA keys in ca.

   *Anonymous <nobody@replay.com>*

 * Generate an error if given an empty string as a cert directory. Also
   generate an error if handed NULL (previously returned 0 to indicate an
   error, but didn't set one).

   *Ben Laurie, reported by Anonymous <nobody@replay.com>*

 * Add prototypes to SSL methods. Make SSL_write's buffer const, at last.

   *Ben Laurie*

 * Fix the dummy function BN_ref_mod_exp() in rsaref.c to have the correct
   parameters. This was causing a warning which killed off the Win32 compile.

   *Steve Henson*

 * Remove C++ style comments from crypto/bn/bn_local.h.

   *Neil Costigan <neil.costigan@celocom.com>*

 * The function OBJ_txt2nid was broken. It was supposed to return a nid
   based on a text string, looking up short and long names and finally
   "dot" format. The "dot" format stuff didn't work. Added new function
   OBJ_txt2obj to do the same but return an ASN1_OBJECT and rewrote
   OBJ_txt2nid to use it. OBJ_txt2obj can also return objects even if the
   OID is not part of the table.

   *Steve Henson*

 * Add prototypes to X509 lookup/verify methods, fixing a bug in
   X509_LOOKUP_by_alias().

   *Ben Laurie*

 * Sort openssl functions by name.

   *Ben Laurie*

 * Get the `gendsa` command working and add it to the `list` command. Remove
   encryption from sample DSA keys (in case anyone is interested the password
   was "1234").

   *Steve Henson*

 * Make *all* `*_free` functions accept a NULL pointer.

   *Frans Heymans <fheymans@isaserver.be>*

 * If a DH key is generated in s3_srvr.c, don't blow it by trying to use
   NULL pointers.

   *Anonymous <nobody@replay.com>*

 * s_server should send the CAfile as acceptable CAs, not its own cert.

   *Bodo Moeller <3moeller@informatik.uni-hamburg.de>*

 * Don't blow it for numeric `-newkey` arguments to `apps/req`.

   *Bodo Moeller <3moeller@informatik.uni-hamburg.de>*

 * Temp key "for export" tests were wrong in s3_srvr.c.

   *Anonymous <nobody@replay.com>*

 * Add prototype for temp key callback functions
   SSL_CTX_set_tmp_{rsa,dh}_callback().

   *Ben Laurie*

 * Make DH_free() tolerate being passed a NULL pointer (like RSA_free() and
   DSA_free()). Make X509_PUBKEY_set() check for errors in d2i_PublicKey().

   *Steve Henson*

 * X509_name_add_entry() freed the wrong thing after an error.

   *Arne Ansper <arne@ats.cyber.ee>*

 * rsa_eay.c would attempt to free a NULL context.

   *Arne Ansper <arne@ats.cyber.ee>*

 * BIO_s_socket() had a broken should_retry() on Windoze.

   *Arne Ansper <arne@ats.cyber.ee>*

 * BIO_f_buffer() didn't pass on BIO_CTRL_FLUSH.

   *Arne Ansper <arne@ats.cyber.ee>*

 * Make sure the already existing X509_STORE->depth variable is initialized
   in X509_STORE_new(), but document the fact that this variable is still
   unused in the certificate verification process.

   *Ralf S. Engelschall*

 * Fix the various library and `apps/` files to free up pkeys obtained from
   X509_PUBKEY_get() et al. Also allow x509.c to handle netscape extensions.

   *Steve Henson*

 * Fix reference counting in X509_PUBKEY_get(). This makes
   demos/maurice/example2.c work, amongst others, probably.

   *Steve Henson and Ben Laurie*

 * First cut of a cleanup for `apps/`. First the `ssleay` program is now named
   `openssl` and second, the shortcut symlinks for the `openssl <command>`
   are no longer created. This way we have a single and consistent command
   line interface `openssl <command>`, similar to `cvs <command>`.

   *Ralf S. Engelschall, Paul Sutton and Ben Laurie*

 * ca.c: move test for DSA keys inside #ifndef NO_DSA. Make pubkey
   BIT STRING wrapper always have zero unused bits.

   *Steve Henson*

 * Add CA.pl, perl version of CA.sh, add extended key usage OID.

   *Steve Henson*

 * Make the top-level INSTALL documentation easier to understand.

   *Paul Sutton*

 * Makefiles updated to exit if an error occurs in a sub-directory
   make (including if user presses ^C) [Paul Sutton]

 * Make Montgomery context stuff explicit in RSA data structure.

   *Ben Laurie*

 * Fix build order of pem and err to allow for generated pem.h.

   *Ben Laurie*

 * Fix renumbering bug in X509_NAME_delete_entry().

   *Ben Laurie*

 * Enhanced the err-ins.pl script so it makes the error library number
   global and can add a library name. This is needed for external ASN1 and
   other error libraries.

   *Steve Henson*

 * Fixed sk_insert which never worked properly.

   *Steve Henson*

 * Fix ASN1 macros so they can handle indefinite length constructed
   EXPLICIT tags. Some non standard certificates use these: they can now
   be read in.

   *Steve Henson*

 * Merged the various old/obsolete SSLeay documentation files (doc/xxx.doc)
   into a single doc/ssleay.txt bundle. This way the information is still
   preserved but no longer messes up this directory. Now it's new room for
   the new set of documentation files.

   *Ralf S. Engelschall*

 * SETs were incorrectly DER encoded. This was a major pain, because they
   shared code with SEQUENCEs, which aren't coded the same. This means that
   almost everything to do with SETs or SEQUENCEs has either changed name or
   number of arguments.

   *Ben Laurie, based on a partial fix by GP Jayan <gp@nsj.co.jp>*

 * Fix test data to work with the above.

   *Ben Laurie*

 * Fix the RSA header declarations that hid a bug I fixed in 0.9.0b but
   was already fixed by Eric for 0.9.1 it seems.

   *Ben Laurie - pointed out by Ulf Möller <ulf@fitug.de>*

 * Autodetect FreeBSD3.

   *Ben Laurie*

 * Fix various bugs in Configure. This affects the following platforms:
   nextstep
   ncr-scde
   unixware-2.0
   unixware-2.0-pentium
   sco5-cc.

   *Ben Laurie*

 * Eliminate generated files from CVS. Reorder tests to regenerate files
   before they are needed.

   *Ben Laurie*

 * Generate Makefile.ssl from Makefile.org (to keep CVS happy).

   *Ben Laurie*

### Changes between 0.9.1b and 0.9.1c  [23-Dec-1998]

 * Added OPENSSL_VERSION_NUMBER to crypto/crypto.h and
   changed SSLeay to OpenSSL in version strings.

   *Ralf S. Engelschall*

 * Some fixups to the top-level documents.

   *Paul Sutton*

 * Fixed the nasty bug where rsaref.h was not found under compile-time
   because the symlink to include/ was missing.

   *Ralf S. Engelschall*

 * Incorporated the popular no-RSA/DSA-only patches
   which allow to compile an RSA-free SSLeay.

   *Andrew Cooke / Interrader Ldt., Ralf S. Engelschall*

 * Fixed nasty rehash problem under `make -f Makefile.ssl links`
   when "ssleay" is still not found.

   *Ralf S. Engelschall*

 * Added more platforms to Configure: Cray T3E, HPUX 11,

   *Ralf S. Engelschall, Beckmann <beckman@acl.lanl.gov>*

 * Updated the README file.

   *Ralf S. Engelschall*

 * Added various .cvsignore files in the CVS repository subdirs
   to make a "cvs update" really silent.

   *Ralf S. Engelschall*

 * Recompiled the error-definition header files and added
   missing symbols to the Win32 linker tables.

   *Ralf S. Engelschall*

 * Cleaned up the top-level documents;
   o new files: CHANGES and LICENSE
   o merged VERSION, HISTORY* and README* files a CHANGES.SSLeay
   o merged COPYRIGHT into LICENSE
   o removed obsolete TODO file
   o renamed MICROSOFT to INSTALL.W32

   *Ralf S. Engelschall*

 * Removed dummy files from the 0.9.1b source tree:
   crypto/asn1/x crypto/bio/cd crypto/bio/fg crypto/bio/grep crypto/bio/vi
   crypto/bn/asm/......add.c crypto/bn/asm/a.out crypto/dsa/f crypto/md5/f
   crypto/pem/gmon.out crypto/perlasm/f crypto/pkcs7/build crypto/rsa/f
   crypto/sha/asm/f crypto/threads/f ms/zzz ssl/f ssl/f.mak test/f
   util/f.mak util/pl/f util/pl/f.mak crypto/bf/bf_locl.old apps/f

   *Ralf S. Engelschall*

 * Added various platform portability fixes.

   *Mark J. Cox*

 * The Genesis of the OpenSSL rpject:
   We start with the latest (unreleased) SSLeay version 0.9.1b which Eric A.
   Young and Tim J. Hudson created while they were working for C2Net until
   summer 1998.

   *The OpenSSL Project*

### Changes between 0.9.0b and 0.9.1b  [not released]

 * Updated a few CA certificates under certs/

   *Eric A. Young*

 * Changed some BIGNUM api stuff.

   *Eric A. Young*

 * Various platform ports: OpenBSD, Ultrix, IRIX 64bit, NetBSD,
   DGUX x86, Linux Alpha, etc.

   *Eric A. Young*

 * New COMP library [crypto/comp/] for SSL Record Layer Compression:
   RLE (dummy implemented) and ZLIB (really implemented when ZLIB is
   available).

   *Eric A. Young*

 * Add -strparse option to asn1pars program which parses nested
   binary structures

   *Dr Stephen Henson <shenson@bigfoot.com>*

 * Added "oid_file" to ssleay.cnf for "ca" and "req" programs.

   *Eric A. Young*

 * DSA fix for "ca" program.

   *Eric A. Young*

 * Added "-genkey" option to "dsaparam" program.

   *Eric A. Young*

 * Added RIPE MD160 (rmd160) message digest.

   *Eric A. Young*

 * Added -a (all) option to "ssleay version" command.

   *Eric A. Young*

 * Added PLATFORM define which is the id given to Configure.

   *Eric A. Young*

 * Added MemCheck_XXXX functions to crypto/mem.c for memory checking.

   *Eric A. Young*

 * Extended the ASN.1 parser routines.

   *Eric A. Young*

 * Extended BIO routines to support REUSEADDR, seek, tell, etc.

   *Eric A. Young*

 * Added a BN_CTX to the BN library.

   *Eric A. Young*

 * Fixed the weak key values in DES library

   *Eric A. Young*

 * Changed API in EVP library for cipher aliases.

   *Eric A. Young*

 * Added support for RC2/64bit cipher.

   *Eric A. Young*

 * Converted the lhash library to the crypto/mem.c functions.

   *Eric A. Young*

 * Added more recognized ASN.1 object ids.

   *Eric A. Young*

 * Added more RSA padding checks for SSL/TLS.

   *Eric A. Young*

 * Added BIO proxy/filter functionality.

   *Eric A. Young*

 * Added extra_certs to SSL_CTX which can be used
   send extra CA certificates to the client in the CA cert chain sending
   process. It can be configured with SSL_CTX_add_extra_chain_cert().

   *Eric A. Young*

 * Now Fortezza is denied in the authentication phase because
   this is key exchange mechanism is not supported by SSLeay at all.

   *Eric A. Young*

 * Additional PKCS1 checks.

   *Eric A. Young*

 * Support the string "TLSv1" for all TLS v1 ciphers.

   *Eric A. Young*

 * Added function SSL_get_ex_data_X509_STORE_CTX_idx() which gives the
   ex_data index of the SSL context in the X509_STORE_CTX ex_data.

   *Eric A. Young*

 * Fixed a few memory leaks.

   *Eric A. Young*

 * Fixed various code and comment typos.

   *Eric A. Young*

 * A minor bug in ssl/s3_clnt.c where there would always be 4 0
   bytes sent in the client random.

   *Edward Bishop <ebishop@spyglass.com>*

<!-- Links -->

[CVE-2024-0727]: https://www.openssl.org/news/vulnerabilities.html#CVE-2024-0727
[CVE-2023-6237]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-6237
[CVE-2023-6129]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-6129
[CVE-2023-5678]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-5678
[CVE-2023-5363]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-5363
[CVE-2023-4807]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-4807
[CVE-2023-3817]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-3817
[CVE-2023-3446]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-3446
[CVE-2023-2975]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-2975
[RFC 2578 (STD 58), section 3.5]: https://datatracker.ietf.org/doc/html/rfc2578#section-3.5
[CVE-2023-2650]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-2650
[CVE-2023-1255]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-1255
[CVE-2023-0466]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0466
[CVE-2023-0465]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0465
[CVE-2023-0464]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0464
[CVE-2023-0401]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0401
[CVE-2023-0286]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0286
[CVE-2023-0217]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0217
[CVE-2023-0216]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0216
[CVE-2023-0215]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0215
[CVE-2022-4450]: https://www.openssl.org/news/vulnerabilities.html#CVE-2022-4450
[CVE-2022-4304]: https://www.openssl.org/news/vulnerabilities.html#CVE-2022-4304
[CVE-2022-4203]: https://www.openssl.org/news/vulnerabilities.html#CVE-2022-4203
[CVE-2022-3996]: https://www.openssl.org/news/vulnerabilities.html#CVE-2022-3996
[CVE-2022-2274]: https://www.openssl.org/news/vulnerabilities.html#CVE-2022-2274
[CVE-2022-2097]: https://www.openssl.org/news/vulnerabilities.html#CVE-2022-2097
[CVE-2020-1971]: https://www.openssl.org/news/vulnerabilities.html#CVE-2020-1971
[CVE-2020-1967]: https://www.openssl.org/news/vulnerabilities.html#CVE-2020-1967
[CVE-2019-1563]: https://www.openssl.org/news/vulnerabilities.html#CVE-2019-1563
[CVE-2019-1559]: https://www.openssl.org/news/vulnerabilities.html#CVE-2019-1559
[CVE-2019-1552]: https://www.openssl.org/news/vulnerabilities.html#CVE-2019-1552
[CVE-2019-1551]: https://www.openssl.org/news/vulnerabilities.html#CVE-2019-1551
[CVE-2019-1549]: https://www.openssl.org/news/vulnerabilities.html#CVE-2019-1549
[CVE-2019-1547]: https://www.openssl.org/news/vulnerabilities.html#CVE-2019-1547
[CVE-2019-1543]: https://www.openssl.org/news/vulnerabilities.html#CVE-2019-1543
[CVE-2018-5407]: https://www.openssl.org/news/vulnerabilities.html#CVE-2018-5407
[CVE-2018-0739]: https://www.openssl.org/news/vulnerabilities.html#CVE-2018-0739
[CVE-2018-0737]: https://www.openssl.org/news/vulnerabilities.html#CVE-2018-0737
[CVE-2018-0735]: https://www.openssl.org/news/vulnerabilities.html#CVE-2018-0735
[CVE-2018-0734]: https://www.openssl.org/news/vulnerabilities.html#CVE-2018-0734
[CVE-2018-0733]: https://www.openssl.org/news/vulnerabilities.html#CVE-2018-0733
[CVE-2018-0732]: https://www.openssl.org/news/vulnerabilities.html#CVE-2018-0732
[CVE-2017-3738]: https://www.openssl.org/news/vulnerabilities.html#CVE-2017-3738
[CVE-2017-3737]: https://www.openssl.org/news/vulnerabilities.html#CVE-2017-3737
[CVE-2017-3736]: https://www.openssl.org/news/vulnerabilities.html#CVE-2017-3736
[CVE-2017-3735]: https://www.openssl.org/news/vulnerabilities.html#CVE-2017-3735
[CVE-2017-3733]: https://www.openssl.org/news/vulnerabilities.html#CVE-2017-3733
[CVE-2017-3732]: https://www.openssl.org/news/vulnerabilities.html#CVE-2017-3732
[CVE-2017-3731]: https://www.openssl.org/news/vulnerabilities.html#CVE-2017-3731
[CVE-2017-3730]: https://www.openssl.org/news/vulnerabilities.html#CVE-2017-3730
[CVE-2016-7055]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-7055
[CVE-2016-7054]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-7054
[CVE-2016-7053]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-7053
[CVE-2016-7052]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-7052
[CVE-2016-6309]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-6309
[CVE-2016-6308]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-6308
[CVE-2016-6307]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-6307
[CVE-2016-6306]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-6306
[CVE-2016-6305]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-6305
[CVE-2016-6304]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-6304
[CVE-2016-6303]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-6303
[CVE-2016-6302]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-6302
[CVE-2016-2183]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2183
[CVE-2016-2182]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2182
[CVE-2016-2181]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2181
[CVE-2016-2180]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2180
[CVE-2016-2179]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2179
[CVE-2016-2178]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2178
[CVE-2016-2177]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2177
[CVE-2016-2176]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2176
[CVE-2016-2109]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2109
[CVE-2016-2107]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2107
[CVE-2016-2106]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2106
[CVE-2016-2105]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2105
[CVE-2016-0800]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-0800
[CVE-2016-0799]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-0799
[CVE-2016-0798]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-0798
[CVE-2016-0797]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-0797
[CVE-2016-0705]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-0705
[CVE-2016-0702]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-0702
[CVE-2016-0701]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-0701
[CVE-2015-3197]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-3197
[CVE-2015-3196]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-3196
[CVE-2015-3195]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-3195
[CVE-2015-3194]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-3194
[CVE-2015-3193]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-3193
[CVE-2015-1793]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-1793
[CVE-2015-1792]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-1792
[CVE-2015-1791]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-1791
[CVE-2015-1790]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-1790
[CVE-2015-1789]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-1789
[CVE-2015-1788]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-1788
[CVE-2015-1787]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-1787
[CVE-2015-0293]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0293
[CVE-2015-0291]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0291
[CVE-2015-0290]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0290
[CVE-2015-0289]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0289
[CVE-2015-0288]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0288
[CVE-2015-0287]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0287
[CVE-2015-0286]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0286
[CVE-2015-0285]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0285
[CVE-2015-0209]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0209
[CVE-2015-0208]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0208
[CVE-2015-0207]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0207
[CVE-2015-0206]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0206
[CVE-2015-0205]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0205
[CVE-2015-0204]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0204
[CVE-2014-8275]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-8275
[CVE-2014-5139]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-5139
[CVE-2014-3572]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3572
[CVE-2014-3571]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3571
[CVE-2014-3570]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3570
[CVE-2014-3569]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3569
[CVE-2014-3568]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3568
[CVE-2014-3567]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3567
[CVE-2014-3566]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3566
[CVE-2014-3513]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3513
[CVE-2014-3512]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3512
[CVE-2014-3511]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3511
[CVE-2014-3510]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3510
[CVE-2014-3509]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3509
[CVE-2014-3508]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3508
[CVE-2014-3507]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3507
[CVE-2014-3506]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3506
[CVE-2014-3505]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3505
[CVE-2014-3470]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3470
[CVE-2014-0224]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-0224
[CVE-2014-0221]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-0221
[CVE-2014-0195]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-0195
[CVE-2014-0160]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-0160
[CVE-2014-0076]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-0076
[CVE-2013-6450]: https://www.openssl.org/news/vulnerabilities.html#CVE-2013-6450
[CVE-2013-4353]: https://www.openssl.org/news/vulnerabilities.html#CVE-2013-4353
[CVE-2013-0169]: https://www.openssl.org/news/vulnerabilities.html#CVE-2013-0169
[CVE-2013-0166]: https://www.openssl.org/news/vulnerabilities.html#CVE-2013-0166
[CVE-2012-2686]: https://www.openssl.org/news/vulnerabilities.html#CVE-2012-2686
[CVE-2012-2333]: https://www.openssl.org/news/vulnerabilities.html#CVE-2012-2333
[CVE-2012-2110]: https://www.openssl.org/news/vulnerabilities.html#CVE-2012-2110
[CVE-2012-0884]: https://www.openssl.org/news/vulnerabilities.html#CVE-2012-0884
[CVE-2012-0050]: https://www.openssl.org/news/vulnerabilities.html#CVE-2012-0050
[CVE-2012-0027]: https://www.openssl.org/news/vulnerabilities.html#CVE-2012-0027
[CVE-2011-4619]: https://www.openssl.org/news/vulnerabilities.html#CVE-2011-4619
[CVE-2011-4577]: https://www.openssl.org/news/vulnerabilities.html#CVE-2011-4577
[CVE-2011-4576]: https://www.openssl.org/news/vulnerabilities.html#CVE-2011-4576
[CVE-2011-4109]: https://www.openssl.org/news/vulnerabilities.html#CVE-2011-4109
[CVE-2011-4108]: https://www.openssl.org/news/vulnerabilities.html#CVE-2011-4108
[CVE-2011-3210]: https://www.openssl.org/news/vulnerabilities.html#CVE-2011-3210
[CVE-2011-3207]: https://www.openssl.org/news/vulnerabilities.html#CVE-2011-3207
[CVE-2011-0014]: https://www.openssl.org/news/vulnerabilities.html#CVE-2011-0014
[CVE-2010-4252]: https://www.openssl.org/news/vulnerabilities.html#CVE-2010-4252
[CVE-2010-4180]: https://www.openssl.org/news/vulnerabilities.html#CVE-2010-4180
[CVE-2010-3864]: https://www.openssl.org/news/vulnerabilities.html#CVE-2010-3864
[CVE-2010-1633]: https://www.openssl.org/news/vulnerabilities.html#CVE-2010-1633
[CVE-2010-0740]: https://www.openssl.org/news/vulnerabilities.html#CVE-2010-0740
[CVE-2010-0433]: https://www.openssl.org/news/vulnerabilities.html#CVE-2010-0433
[CVE-2009-4355]: https://www.openssl.org/news/vulnerabilities.html#CVE-2009-4355
[CVE-2009-3555]: https://www.openssl.org/news/vulnerabilities.html#CVE-2009-3555
[CVE-2009-3245]: https://www.openssl.org/news/vulnerabilities.html#CVE-2009-3245
[CVE-2009-1386]: https://www.openssl.org/news/vulnerabilities.html#CVE-2009-1386
[CVE-2009-1379]: https://www.openssl.org/news/vulnerabilities.html#CVE-2009-1379
[CVE-2009-1378]: https://www.openssl.org/news/vulnerabilities.html#CVE-2009-1378
[CVE-2009-1377]: https://www.openssl.org/news/vulnerabilities.html#CVE-2009-1377
[CVE-2009-0789]: https://www.openssl.org/news/vulnerabilities.html#CVE-2009-0789
[CVE-2009-0591]: https://www.openssl.org/news/vulnerabilities.html#CVE-2009-0591
[CVE-2009-0590]: https://www.openssl.org/news/vulnerabilities.html#CVE-2009-0590
[CVE-2008-5077]: https://www.openssl.org/news/vulnerabilities.html#CVE-2008-5077
[CVE-2008-1678]: https://www.openssl.org/news/vulnerabilities.html#CVE-2008-1678
[CVE-2008-1672]: https://www.openssl.org/news/vulnerabilities.html#CVE-2008-1672
[CVE-2008-0891]: https://www.openssl.org/news/vulnerabilities.html#CVE-2008-0891
[CVE-2007-5135]: https://www.openssl.org/news/vulnerabilities.html#CVE-2007-5135
[CVE-2007-4995]: https://www.openssl.org/news/vulnerabilities.html#CVE-2007-4995
[CVE-2006-4343]: https://www.openssl.org/news/vulnerabilities.html#CVE-2006-4343
[CVE-2006-4339]: https://www.openssl.org/news/vulnerabilities.html#CVE-2006-4339
[CVE-2006-3738]: https://www.openssl.org/news/vulnerabilities.html#CVE-2006-3738
[CVE-2006-2940]: https://www.openssl.org/news/vulnerabilities.html#CVE-2006-2940
[CVE-2006-2937]: https://www.openssl.org/news/vulnerabilities.html#CVE-2006-2937
[CVE-2005-2969]: https://www.openssl.org/news/vulnerabilities.html#CVE-2005-2969
[CVE-2004-0112]: https://www.openssl.org/news/vulnerabilities.html#CVE-2004-0112
[CVE-2004-0079]: https://www.openssl.org/news/vulnerabilities.html#CVE-2004-0079
[CVE-2003-0851]: https://www.openssl.org/news/vulnerabilities.html#CVE-2003-0851
[CVE-2003-0545]: https://www.openssl.org/news/vulnerabilities.html#CVE-2003-0545
[CVE-2003-0544]: https://www.openssl.org/news/vulnerabilities.html#CVE-2003-0544
[CVE-2003-0543]: https://www.openssl.org/news/vulnerabilities.html#CVE-2003-0543
[CVE-2003-0078]: https://www.openssl.org/news/vulnerabilities.html#CVE-2003-0078
[CVE-2002-0659]: https://www.openssl.org/news/vulnerabilities.html#CVE-2002-0659
[CVE-2002-0657]: https://www.openssl.org/news/vulnerabilities.html#CVE-2002-0657
[CVE-2002-0656]: https://www.openssl.org/news/vulnerabilities.html#CVE-2002-0656
[CVE-2002-0655]: https://www.openssl.org/news/vulnerabilities.html#CVE-2002-0655