1 | /*
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2 | * Copyright 2016-2022 The OpenSSL Project Authors. All Rights Reserved.
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3 | *
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4 | * Licensed under the Apache License 2.0 (the "License"). You may not use
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5 | * this file except in compliance with the License. You can obtain a copy
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6 | * in the file LICENSE in the source distribution or at
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7 | * https://www.openssl.org/source/license.html
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8 | */
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9 |
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10 | #include <stdlib.h>
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11 | #include "ssl_local.h"
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12 | #include "internal/ktls.h"
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13 | #include "record/record_local.h"
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14 | #include "internal/cryptlib.h"
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15 | #include <openssl/evp.h>
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16 | #include <openssl/kdf.h>
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17 | #include <openssl/core_names.h>
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18 |
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19 | #define TLS13_MAX_LABEL_LEN 249
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20 |
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21 | /* ASCII: "tls13 ", in hex for EBCDIC compatibility */
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22 | static const unsigned char label_prefix[] = "\x74\x6C\x73\x31\x33\x20";
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23 |
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24 | /*
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25 | * Given a |secret|; a |label| of length |labellen|; and |data| of length
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26 | * |datalen| (e.g. typically a hash of the handshake messages), derive a new
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27 | * secret |outlen| bytes long and store it in the location pointed to be |out|.
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28 | * The |data| value may be zero length. Any errors will be treated as fatal if
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29 | * |fatal| is set. Returns 1 on success 0 on failure.
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30 | */
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31 | int tls13_hkdf_expand(SSL *s, const EVP_MD *md, const unsigned char *secret,
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32 | const unsigned char *label, size_t labellen,
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33 | const unsigned char *data, size_t datalen,
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34 | unsigned char *out, size_t outlen, int fatal)
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35 | {
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36 | EVP_KDF *kdf = EVP_KDF_fetch(s->ctx->libctx, OSSL_KDF_NAME_TLS1_3_KDF,
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37 | s->ctx->propq);
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38 | EVP_KDF_CTX *kctx;
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39 | OSSL_PARAM params[7], *p = params;
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40 | int mode = EVP_PKEY_HKDEF_MODE_EXPAND_ONLY;
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41 | const char *mdname = EVP_MD_get0_name(md);
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42 | int ret;
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43 | size_t hashlen;
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44 |
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45 | kctx = EVP_KDF_CTX_new(kdf);
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46 | EVP_KDF_free(kdf);
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47 | if (kctx == NULL)
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48 | return 0;
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49 |
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50 | if (labellen > TLS13_MAX_LABEL_LEN) {
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51 | if (fatal) {
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52 | SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
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53 | } else {
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54 | /*
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55 | * Probably we have been called from SSL_export_keying_material(),
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56 | * or SSL_export_keying_material_early().
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57 | */
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58 | ERR_raise(ERR_LIB_SSL, SSL_R_TLS_ILLEGAL_EXPORTER_LABEL);
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59 | }
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60 | EVP_KDF_CTX_free(kctx);
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61 | return 0;
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62 | }
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63 |
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64 | if ((ret = EVP_MD_get_size(md)) <= 0) {
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65 | EVP_KDF_CTX_free(kctx);
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66 | if (fatal)
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67 | SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
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68 | else
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69 | ERR_raise(ERR_LIB_SSL, ERR_R_INTERNAL_ERROR);
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70 | return 0;
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71 | }
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72 | hashlen = (size_t)ret;
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73 |
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74 | *p++ = OSSL_PARAM_construct_int(OSSL_KDF_PARAM_MODE, &mode);
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75 | *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,
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76 | (char *)mdname, 0);
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77 | *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY,
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78 | (unsigned char *)secret, hashlen);
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79 | *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_PREFIX,
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80 | (unsigned char *)label_prefix,
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81 | sizeof(label_prefix) - 1);
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82 | *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_LABEL,
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83 | (unsigned char *)label, labellen);
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84 | if (data != NULL)
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85 | *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_DATA,
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86 | (unsigned char *)data,
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87 | datalen);
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88 | *p++ = OSSL_PARAM_construct_end();
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89 |
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90 | ret = EVP_KDF_derive(kctx, out, outlen, params) <= 0;
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91 | EVP_KDF_CTX_free(kctx);
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92 |
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93 | if (ret != 0) {
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94 | if (fatal)
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95 | SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
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96 | else
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97 | ERR_raise(ERR_LIB_SSL, ERR_R_INTERNAL_ERROR);
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98 | }
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99 |
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100 | return ret == 0;
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101 | }
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102 |
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103 | /*
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104 | * Given a |secret| generate a |key| of length |keylen| bytes. Returns 1 on
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105 | * success 0 on failure.
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106 | */
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107 | int tls13_derive_key(SSL *s, const EVP_MD *md, const unsigned char *secret,
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108 | unsigned char *key, size_t keylen)
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109 | {
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110 | /* ASCII: "key", in hex for EBCDIC compatibility */
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111 | static const unsigned char keylabel[] = "\x6B\x65\x79";
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112 |
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113 | return tls13_hkdf_expand(s, md, secret, keylabel, sizeof(keylabel) - 1,
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114 | NULL, 0, key, keylen, 1);
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115 | }
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116 |
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117 | /*
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118 | * Given a |secret| generate an |iv| of length |ivlen| bytes. Returns 1 on
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119 | * success 0 on failure.
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120 | */
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121 | int tls13_derive_iv(SSL *s, const EVP_MD *md, const unsigned char *secret,
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122 | unsigned char *iv, size_t ivlen)
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123 | {
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124 | /* ASCII: "iv", in hex for EBCDIC compatibility */
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125 | static const unsigned char ivlabel[] = "\x69\x76";
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126 |
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127 | return tls13_hkdf_expand(s, md, secret, ivlabel, sizeof(ivlabel) - 1,
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128 | NULL, 0, iv, ivlen, 1);
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129 | }
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130 |
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131 | int tls13_derive_finishedkey(SSL *s, const EVP_MD *md,
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132 | const unsigned char *secret,
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133 | unsigned char *fin, size_t finlen)
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134 | {
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135 | /* ASCII: "finished", in hex for EBCDIC compatibility */
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136 | static const unsigned char finishedlabel[] = "\x66\x69\x6E\x69\x73\x68\x65\x64";
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137 |
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138 | return tls13_hkdf_expand(s, md, secret, finishedlabel,
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139 | sizeof(finishedlabel) - 1, NULL, 0, fin, finlen, 1);
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140 | }
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141 |
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142 | /*
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143 | * Given the previous secret |prevsecret| and a new input secret |insecret| of
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144 | * length |insecretlen|, generate a new secret and store it in the location
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145 | * pointed to by |outsecret|. Returns 1 on success 0 on failure.
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146 | */
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147 | int tls13_generate_secret(SSL *s, const EVP_MD *md,
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148 | const unsigned char *prevsecret,
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149 | const unsigned char *insecret,
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150 | size_t insecretlen,
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151 | unsigned char *outsecret)
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152 | {
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153 | size_t mdlen;
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154 | int mdleni;
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155 | int ret;
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156 | EVP_KDF *kdf;
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157 | EVP_KDF_CTX *kctx;
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158 | OSSL_PARAM params[7], *p = params;
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159 | int mode = EVP_PKEY_HKDEF_MODE_EXTRACT_ONLY;
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160 | const char *mdname = EVP_MD_get0_name(md);
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161 | /* ASCII: "derived", in hex for EBCDIC compatibility */
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162 | static const char derived_secret_label[] = "\x64\x65\x72\x69\x76\x65\x64";
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163 |
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164 | kdf = EVP_KDF_fetch(s->ctx->libctx, OSSL_KDF_NAME_TLS1_3_KDF, s->ctx->propq);
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165 | kctx = EVP_KDF_CTX_new(kdf);
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166 | EVP_KDF_free(kdf);
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167 | if (kctx == NULL) {
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168 | SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
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169 | return 0;
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170 | }
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171 |
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172 | mdleni = EVP_MD_get_size(md);
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173 | /* Ensure cast to size_t is safe */
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174 | if (!ossl_assert(mdleni >= 0)) {
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175 | SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
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176 | EVP_KDF_CTX_free(kctx);
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177 | return 0;
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178 | }
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179 | mdlen = (size_t)mdleni;
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180 |
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181 | *p++ = OSSL_PARAM_construct_int(OSSL_KDF_PARAM_MODE, &mode);
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182 | *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,
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183 | (char *)mdname, 0);
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184 | if (insecret != NULL)
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185 | *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY,
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186 | (unsigned char *)insecret,
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187 | insecretlen);
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188 | if (prevsecret != NULL)
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189 | *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_SALT,
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190 | (unsigned char *)prevsecret, mdlen);
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191 | *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_PREFIX,
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192 | (unsigned char *)label_prefix,
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193 | sizeof(label_prefix) - 1);
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194 | *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_LABEL,
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195 | (unsigned char *)derived_secret_label,
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196 | sizeof(derived_secret_label) - 1);
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197 | *p++ = OSSL_PARAM_construct_end();
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198 |
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199 | ret = EVP_KDF_derive(kctx, outsecret, mdlen, params) <= 0;
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200 |
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201 | if (ret != 0)
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202 | SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
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203 |
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204 | EVP_KDF_CTX_free(kctx);
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205 | return ret == 0;
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206 | }
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207 |
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208 | /*
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209 | * Given an input secret |insecret| of length |insecretlen| generate the
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210 | * handshake secret. This requires the early secret to already have been
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211 | * generated. Returns 1 on success 0 on failure.
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212 | */
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213 | int tls13_generate_handshake_secret(SSL *s, const unsigned char *insecret,
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214 | size_t insecretlen)
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215 | {
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216 | /* Calls SSLfatal() if required */
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217 | return tls13_generate_secret(s, ssl_handshake_md(s), s->early_secret,
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218 | insecret, insecretlen,
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219 | (unsigned char *)&s->handshake_secret);
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220 | }
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221 |
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222 | /*
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223 | * Given the handshake secret |prev| of length |prevlen| generate the master
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224 | * secret and store its length in |*secret_size|. Returns 1 on success 0 on
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225 | * failure.
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226 | */
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227 | int tls13_generate_master_secret(SSL *s, unsigned char *out,
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228 | unsigned char *prev, size_t prevlen,
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229 | size_t *secret_size)
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230 | {
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231 | const EVP_MD *md = ssl_handshake_md(s);
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232 |
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233 | *secret_size = EVP_MD_get_size(md);
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234 | /* Calls SSLfatal() if required */
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235 | return tls13_generate_secret(s, md, prev, NULL, 0, out);
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236 | }
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237 |
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238 | /*
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239 | * Generates the mac for the Finished message. Returns the length of the MAC or
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240 | * 0 on error.
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241 | */
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242 | size_t tls13_final_finish_mac(SSL *s, const char *str, size_t slen,
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243 | unsigned char *out)
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244 | {
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245 | const EVP_MD *md = ssl_handshake_md(s);
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246 | const char *mdname = EVP_MD_get0_name(md);
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247 | unsigned char hash[EVP_MAX_MD_SIZE];
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248 | unsigned char finsecret[EVP_MAX_MD_SIZE];
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249 | unsigned char *key = NULL;
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250 | size_t len = 0, hashlen;
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251 | OSSL_PARAM params[2], *p = params;
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252 |
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253 | if (md == NULL)
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254 | return 0;
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255 |
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256 | /* Safe to cast away const here since we're not "getting" any data */
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257 | if (s->ctx->propq != NULL)
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258 | *p++ = OSSL_PARAM_construct_utf8_string(OSSL_ALG_PARAM_PROPERTIES,
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259 | (char *)s->ctx->propq,
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260 | 0);
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261 | *p = OSSL_PARAM_construct_end();
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262 |
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263 | if (!ssl_handshake_hash(s, hash, sizeof(hash), &hashlen)) {
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264 | /* SSLfatal() already called */
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265 | goto err;
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266 | }
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267 |
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268 | if (str == s->method->ssl3_enc->server_finished_label) {
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269 | key = s->server_finished_secret;
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270 | } else if (SSL_IS_FIRST_HANDSHAKE(s)) {
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271 | key = s->client_finished_secret;
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272 | } else {
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273 | if (!tls13_derive_finishedkey(s, md,
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274 | s->client_app_traffic_secret,
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275 | finsecret, hashlen))
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276 | goto err;
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277 | key = finsecret;
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278 | }
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279 |
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280 | if (!EVP_Q_mac(s->ctx->libctx, "HMAC", s->ctx->propq, mdname,
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281 | params, key, hashlen, hash, hashlen,
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282 | /* outsize as per sizeof(peer_finish_md) */
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283 | out, EVP_MAX_MD_SIZE * 2, &len)) {
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284 | SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
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285 | goto err;
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286 | }
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287 |
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288 | err:
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289 | OPENSSL_cleanse(finsecret, sizeof(finsecret));
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290 | return len;
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291 | }
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292 |
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293 | /*
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294 | * There isn't really a key block in TLSv1.3, but we still need this function
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295 | * for initialising the cipher and hash. Returns 1 on success or 0 on failure.
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296 | */
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297 | int tls13_setup_key_block(SSL *s)
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298 | {
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299 | const EVP_CIPHER *c;
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300 | const EVP_MD *hash;
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301 |
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302 | s->session->cipher = s->s3.tmp.new_cipher;
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303 | if (!ssl_cipher_get_evp(s->ctx, s->session, &c, &hash, NULL, NULL, NULL,
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304 | 0)) {
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305 | /* Error is already recorded */
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306 | SSLfatal_alert(s, SSL_AD_INTERNAL_ERROR);
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307 | return 0;
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308 | }
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309 |
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310 | ssl_evp_cipher_free(s->s3.tmp.new_sym_enc);
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311 | s->s3.tmp.new_sym_enc = c;
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312 | ssl_evp_md_free(s->s3.tmp.new_hash);
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313 | s->s3.tmp.new_hash = hash;
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314 |
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315 | return 1;
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316 | }
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317 |
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318 | static int derive_secret_key_and_iv(SSL *s, int sending, const EVP_MD *md,
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319 | const EVP_CIPHER *ciph,
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320 | const unsigned char *insecret,
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321 | const unsigned char *hash,
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322 | const unsigned char *label,
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323 | size_t labellen, unsigned char *secret,
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324 | unsigned char *key, unsigned char *iv,
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325 | EVP_CIPHER_CTX *ciph_ctx)
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326 | {
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327 | size_t ivlen, keylen, taglen;
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328 | int hashleni = EVP_MD_get_size(md);
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329 | size_t hashlen;
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330 |
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331 | /* Ensure cast to size_t is safe */
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332 | if (!ossl_assert(hashleni >= 0)) {
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333 | SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
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334 | return 0;
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335 | }
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336 | hashlen = (size_t)hashleni;
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337 |
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338 | if (!tls13_hkdf_expand(s, md, insecret, label, labellen, hash, hashlen,
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339 | secret, hashlen, 1)) {
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340 | /* SSLfatal() already called */
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341 | return 0;
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342 | }
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343 |
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344 | keylen = EVP_CIPHER_get_key_length(ciph);
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345 | if (EVP_CIPHER_get_mode(ciph) == EVP_CIPH_CCM_MODE) {
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346 | uint32_t algenc;
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347 |
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348 | ivlen = EVP_CCM_TLS_IV_LEN;
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349 | if (s->s3.tmp.new_cipher != NULL) {
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350 | algenc = s->s3.tmp.new_cipher->algorithm_enc;
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351 | } else if (s->session->cipher != NULL) {
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352 | /* We've not selected a cipher yet - we must be doing early data */
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353 | algenc = s->session->cipher->algorithm_enc;
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354 | } else if (s->psksession != NULL && s->psksession->cipher != NULL) {
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355 | /* We must be doing early data with out-of-band PSK */
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356 | algenc = s->psksession->cipher->algorithm_enc;
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357 | } else {
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358 | SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
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359 | return 0;
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360 | }
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361 | if (algenc & (SSL_AES128CCM8 | SSL_AES256CCM8))
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362 | taglen = EVP_CCM8_TLS_TAG_LEN;
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363 | else
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364 | taglen = EVP_CCM_TLS_TAG_LEN;
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365 | } else {
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366 | ivlen = EVP_CIPHER_get_iv_length(ciph);
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367 | taglen = 0;
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368 | }
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369 |
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370 | if (!tls13_derive_key(s, md, secret, key, keylen)
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371 | || !tls13_derive_iv(s, md, secret, iv, ivlen)) {
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372 | /* SSLfatal() already called */
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373 | return 0;
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374 | }
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375 |
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376 | if (EVP_CipherInit_ex(ciph_ctx, ciph, NULL, NULL, NULL, sending) <= 0
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377 | || EVP_CIPHER_CTX_ctrl(ciph_ctx, EVP_CTRL_AEAD_SET_IVLEN, ivlen, NULL) <= 0
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378 | || (taglen != 0 && EVP_CIPHER_CTX_ctrl(ciph_ctx, EVP_CTRL_AEAD_SET_TAG,
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379 | taglen, NULL) <= 0)
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380 | || EVP_CipherInit_ex(ciph_ctx, NULL, NULL, key, NULL, -1) <= 0) {
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381 | SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
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382 | return 0;
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383 | }
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384 |
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385 | return 1;
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386 | }
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387 |
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388 | int tls13_change_cipher_state(SSL *s, int which)
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389 | {
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390 | /* ASCII: "c e traffic", in hex for EBCDIC compatibility */
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391 | static const unsigned char client_early_traffic[] = "\x63\x20\x65\x20\x74\x72\x61\x66\x66\x69\x63";
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392 | /* ASCII: "c hs traffic", in hex for EBCDIC compatibility */
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393 | static const unsigned char client_handshake_traffic[] = "\x63\x20\x68\x73\x20\x74\x72\x61\x66\x66\x69\x63";
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394 | /* ASCII: "c ap traffic", in hex for EBCDIC compatibility */
|
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395 | static const unsigned char client_application_traffic[] = "\x63\x20\x61\x70\x20\x74\x72\x61\x66\x66\x69\x63";
|
---|
396 | /* ASCII: "s hs traffic", in hex for EBCDIC compatibility */
|
---|
397 | static const unsigned char server_handshake_traffic[] = "\x73\x20\x68\x73\x20\x74\x72\x61\x66\x66\x69\x63";
|
---|
398 | /* ASCII: "s ap traffic", in hex for EBCDIC compatibility */
|
---|
399 | static const unsigned char server_application_traffic[] = "\x73\x20\x61\x70\x20\x74\x72\x61\x66\x66\x69\x63";
|
---|
400 | /* ASCII: "exp master", in hex for EBCDIC compatibility */
|
---|
401 | static const unsigned char exporter_master_secret[] = "\x65\x78\x70\x20\x6D\x61\x73\x74\x65\x72";
|
---|
402 | /* ASCII: "res master", in hex for EBCDIC compatibility */
|
---|
403 | static const unsigned char resumption_master_secret[] = "\x72\x65\x73\x20\x6D\x61\x73\x74\x65\x72";
|
---|
404 | /* ASCII: "e exp master", in hex for EBCDIC compatibility */
|
---|
405 | static const unsigned char early_exporter_master_secret[] = "\x65\x20\x65\x78\x70\x20\x6D\x61\x73\x74\x65\x72";
|
---|
406 | unsigned char *iv;
|
---|
407 | unsigned char key[EVP_MAX_KEY_LENGTH];
|
---|
408 | unsigned char secret[EVP_MAX_MD_SIZE];
|
---|
409 | unsigned char hashval[EVP_MAX_MD_SIZE];
|
---|
410 | unsigned char *hash = hashval;
|
---|
411 | unsigned char *insecret;
|
---|
412 | unsigned char *finsecret = NULL;
|
---|
413 | const char *log_label = NULL;
|
---|
414 | EVP_CIPHER_CTX *ciph_ctx;
|
---|
415 | size_t finsecretlen = 0;
|
---|
416 | const unsigned char *label;
|
---|
417 | size_t labellen, hashlen = 0;
|
---|
418 | int ret = 0;
|
---|
419 | const EVP_MD *md = NULL;
|
---|
420 | const EVP_CIPHER *cipher = NULL;
|
---|
421 | #if !defined(OPENSSL_NO_KTLS) && defined(OPENSSL_KTLS_TLS13)
|
---|
422 | ktls_crypto_info_t crypto_info;
|
---|
423 | BIO *bio;
|
---|
424 | #endif
|
---|
425 |
|
---|
426 | if (which & SSL3_CC_READ) {
|
---|
427 | if (s->enc_read_ctx != NULL) {
|
---|
428 | EVP_CIPHER_CTX_reset(s->enc_read_ctx);
|
---|
429 | } else {
|
---|
430 | s->enc_read_ctx = EVP_CIPHER_CTX_new();
|
---|
431 | if (s->enc_read_ctx == NULL) {
|
---|
432 | SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
|
---|
433 | goto err;
|
---|
434 | }
|
---|
435 | }
|
---|
436 | ciph_ctx = s->enc_read_ctx;
|
---|
437 | iv = s->read_iv;
|
---|
438 |
|
---|
439 | RECORD_LAYER_reset_read_sequence(&s->rlayer);
|
---|
440 | } else {
|
---|
441 | s->statem.enc_write_state = ENC_WRITE_STATE_INVALID;
|
---|
442 | if (s->enc_write_ctx != NULL) {
|
---|
443 | EVP_CIPHER_CTX_reset(s->enc_write_ctx);
|
---|
444 | } else {
|
---|
445 | s->enc_write_ctx = EVP_CIPHER_CTX_new();
|
---|
446 | if (s->enc_write_ctx == NULL) {
|
---|
447 | SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
|
---|
448 | goto err;
|
---|
449 | }
|
---|
450 | }
|
---|
451 | ciph_ctx = s->enc_write_ctx;
|
---|
452 | iv = s->write_iv;
|
---|
453 |
|
---|
454 | RECORD_LAYER_reset_write_sequence(&s->rlayer);
|
---|
455 | }
|
---|
456 |
|
---|
457 | if (((which & SSL3_CC_CLIENT) && (which & SSL3_CC_WRITE))
|
---|
458 | || ((which & SSL3_CC_SERVER) && (which & SSL3_CC_READ))) {
|
---|
459 | if (which & SSL3_CC_EARLY) {
|
---|
460 | EVP_MD_CTX *mdctx = NULL;
|
---|
461 | long handlen;
|
---|
462 | void *hdata;
|
---|
463 | unsigned int hashlenui;
|
---|
464 | const SSL_CIPHER *sslcipher = SSL_SESSION_get0_cipher(s->session);
|
---|
465 |
|
---|
466 | insecret = s->early_secret;
|
---|
467 | label = client_early_traffic;
|
---|
468 | labellen = sizeof(client_early_traffic) - 1;
|
---|
469 | log_label = CLIENT_EARLY_LABEL;
|
---|
470 |
|
---|
471 | handlen = BIO_get_mem_data(s->s3.handshake_buffer, &hdata);
|
---|
472 | if (handlen <= 0) {
|
---|
473 | SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_HANDSHAKE_LENGTH);
|
---|
474 | goto err;
|
---|
475 | }
|
---|
476 |
|
---|
477 | if (s->early_data_state == SSL_EARLY_DATA_CONNECTING
|
---|
478 | && s->max_early_data > 0
|
---|
479 | && s->session->ext.max_early_data == 0) {
|
---|
480 | /*
|
---|
481 | * If we are attempting to send early data, and we've decided to
|
---|
482 | * actually do it but max_early_data in s->session is 0 then we
|
---|
483 | * must be using an external PSK.
|
---|
484 | */
|
---|
485 | if (!ossl_assert(s->psksession != NULL
|
---|
486 | && s->max_early_data ==
|
---|
487 | s->psksession->ext.max_early_data)) {
|
---|
488 | SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
|
---|
489 | goto err;
|
---|
490 | }
|
---|
491 | sslcipher = SSL_SESSION_get0_cipher(s->psksession);
|
---|
492 | }
|
---|
493 | if (sslcipher == NULL) {
|
---|
494 | SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_PSK);
|
---|
495 | goto err;
|
---|
496 | }
|
---|
497 |
|
---|
498 | /*
|
---|
499 | * We need to calculate the handshake digest using the digest from
|
---|
500 | * the session. We haven't yet selected our ciphersuite so we can't
|
---|
501 | * use ssl_handshake_md().
|
---|
502 | */
|
---|
503 | mdctx = EVP_MD_CTX_new();
|
---|
504 | if (mdctx == NULL) {
|
---|
505 | SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
|
---|
506 | goto err;
|
---|
507 | }
|
---|
508 |
|
---|
509 | /*
|
---|
510 | * This ups the ref count on cipher so we better make sure we free
|
---|
511 | * it again
|
---|
512 | */
|
---|
513 | if (!ssl_cipher_get_evp_cipher(s->ctx, sslcipher, &cipher)) {
|
---|
514 | /* Error is already recorded */
|
---|
515 | SSLfatal_alert(s, SSL_AD_INTERNAL_ERROR);
|
---|
516 | EVP_MD_CTX_free(mdctx);
|
---|
517 | goto err;
|
---|
518 | }
|
---|
519 |
|
---|
520 | md = ssl_md(s->ctx, sslcipher->algorithm2);
|
---|
521 | if (md == NULL || !EVP_DigestInit_ex(mdctx, md, NULL)
|
---|
522 | || !EVP_DigestUpdate(mdctx, hdata, handlen)
|
---|
523 | || !EVP_DigestFinal_ex(mdctx, hashval, &hashlenui)) {
|
---|
524 | SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
|
---|
525 | EVP_MD_CTX_free(mdctx);
|
---|
526 | goto err;
|
---|
527 | }
|
---|
528 | hashlen = hashlenui;
|
---|
529 | EVP_MD_CTX_free(mdctx);
|
---|
530 |
|
---|
531 | if (!tls13_hkdf_expand(s, md, insecret,
|
---|
532 | early_exporter_master_secret,
|
---|
533 | sizeof(early_exporter_master_secret) - 1,
|
---|
534 | hashval, hashlen,
|
---|
535 | s->early_exporter_master_secret, hashlen,
|
---|
536 | 1)) {
|
---|
537 | SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
|
---|
538 | goto err;
|
---|
539 | }
|
---|
540 |
|
---|
541 | if (!ssl_log_secret(s, EARLY_EXPORTER_SECRET_LABEL,
|
---|
542 | s->early_exporter_master_secret, hashlen)) {
|
---|
543 | /* SSLfatal() already called */
|
---|
544 | goto err;
|
---|
545 | }
|
---|
546 | } else if (which & SSL3_CC_HANDSHAKE) {
|
---|
547 | insecret = s->handshake_secret;
|
---|
548 | finsecret = s->client_finished_secret;
|
---|
549 | finsecretlen = EVP_MD_get_size(ssl_handshake_md(s));
|
---|
550 | label = client_handshake_traffic;
|
---|
551 | labellen = sizeof(client_handshake_traffic) - 1;
|
---|
552 | log_label = CLIENT_HANDSHAKE_LABEL;
|
---|
553 | /*
|
---|
554 | * The handshake hash used for the server read/client write handshake
|
---|
555 | * traffic secret is the same as the hash for the server
|
---|
556 | * write/client read handshake traffic secret. However, if we
|
---|
557 | * processed early data then we delay changing the server
|
---|
558 | * read/client write cipher state until later, and the handshake
|
---|
559 | * hashes have moved on. Therefore we use the value saved earlier
|
---|
560 | * when we did the server write/client read change cipher state.
|
---|
561 | */
|
---|
562 | hash = s->handshake_traffic_hash;
|
---|
563 | } else {
|
---|
564 | insecret = s->master_secret;
|
---|
565 | label = client_application_traffic;
|
---|
566 | labellen = sizeof(client_application_traffic) - 1;
|
---|
567 | log_label = CLIENT_APPLICATION_LABEL;
|
---|
568 | /*
|
---|
569 | * For this we only use the handshake hashes up until the server
|
---|
570 | * Finished hash. We do not include the client's Finished, which is
|
---|
571 | * what ssl_handshake_hash() would give us. Instead we use the
|
---|
572 | * previously saved value.
|
---|
573 | */
|
---|
574 | hash = s->server_finished_hash;
|
---|
575 | }
|
---|
576 | } else {
|
---|
577 | /* Early data never applies to client-read/server-write */
|
---|
578 | if (which & SSL3_CC_HANDSHAKE) {
|
---|
579 | insecret = s->handshake_secret;
|
---|
580 | finsecret = s->server_finished_secret;
|
---|
581 | finsecretlen = EVP_MD_get_size(ssl_handshake_md(s));
|
---|
582 | label = server_handshake_traffic;
|
---|
583 | labellen = sizeof(server_handshake_traffic) - 1;
|
---|
584 | log_label = SERVER_HANDSHAKE_LABEL;
|
---|
585 | } else {
|
---|
586 | insecret = s->master_secret;
|
---|
587 | label = server_application_traffic;
|
---|
588 | labellen = sizeof(server_application_traffic) - 1;
|
---|
589 | log_label = SERVER_APPLICATION_LABEL;
|
---|
590 | }
|
---|
591 | }
|
---|
592 |
|
---|
593 | if (!(which & SSL3_CC_EARLY)) {
|
---|
594 | md = ssl_handshake_md(s);
|
---|
595 | cipher = s->s3.tmp.new_sym_enc;
|
---|
596 | if (!ssl3_digest_cached_records(s, 1)
|
---|
597 | || !ssl_handshake_hash(s, hashval, sizeof(hashval), &hashlen)) {
|
---|
598 | /* SSLfatal() already called */;
|
---|
599 | goto err;
|
---|
600 | }
|
---|
601 | }
|
---|
602 |
|
---|
603 | /*
|
---|
604 | * Save the hash of handshakes up to now for use when we calculate the
|
---|
605 | * client application traffic secret
|
---|
606 | */
|
---|
607 | if (label == server_application_traffic)
|
---|
608 | memcpy(s->server_finished_hash, hashval, hashlen);
|
---|
609 |
|
---|
610 | if (label == server_handshake_traffic)
|
---|
611 | memcpy(s->handshake_traffic_hash, hashval, hashlen);
|
---|
612 |
|
---|
613 | if (label == client_application_traffic) {
|
---|
614 | /*
|
---|
615 | * We also create the resumption master secret, but this time use the
|
---|
616 | * hash for the whole handshake including the Client Finished
|
---|
617 | */
|
---|
618 | if (!tls13_hkdf_expand(s, ssl_handshake_md(s), insecret,
|
---|
619 | resumption_master_secret,
|
---|
620 | sizeof(resumption_master_secret) - 1,
|
---|
621 | hashval, hashlen, s->resumption_master_secret,
|
---|
622 | hashlen, 1)) {
|
---|
623 | /* SSLfatal() already called */
|
---|
624 | goto err;
|
---|
625 | }
|
---|
626 | }
|
---|
627 |
|
---|
628 | /* check whether cipher is known */
|
---|
629 | if(!ossl_assert(cipher != NULL))
|
---|
630 | goto err;
|
---|
631 |
|
---|
632 | if (!derive_secret_key_and_iv(s, which & SSL3_CC_WRITE, md, cipher,
|
---|
633 | insecret, hash, label, labellen, secret, key,
|
---|
634 | iv, ciph_ctx)) {
|
---|
635 | /* SSLfatal() already called */
|
---|
636 | goto err;
|
---|
637 | }
|
---|
638 |
|
---|
639 | if (label == server_application_traffic) {
|
---|
640 | memcpy(s->server_app_traffic_secret, secret, hashlen);
|
---|
641 | /* Now we create the exporter master secret */
|
---|
642 | if (!tls13_hkdf_expand(s, ssl_handshake_md(s), insecret,
|
---|
643 | exporter_master_secret,
|
---|
644 | sizeof(exporter_master_secret) - 1,
|
---|
645 | hash, hashlen, s->exporter_master_secret,
|
---|
646 | hashlen, 1)) {
|
---|
647 | /* SSLfatal() already called */
|
---|
648 | goto err;
|
---|
649 | }
|
---|
650 |
|
---|
651 | if (!ssl_log_secret(s, EXPORTER_SECRET_LABEL, s->exporter_master_secret,
|
---|
652 | hashlen)) {
|
---|
653 | /* SSLfatal() already called */
|
---|
654 | goto err;
|
---|
655 | }
|
---|
656 | } else if (label == client_application_traffic)
|
---|
657 | memcpy(s->client_app_traffic_secret, secret, hashlen);
|
---|
658 |
|
---|
659 | if (!ssl_log_secret(s, log_label, secret, hashlen)) {
|
---|
660 | /* SSLfatal() already called */
|
---|
661 | goto err;
|
---|
662 | }
|
---|
663 |
|
---|
664 | if (finsecret != NULL
|
---|
665 | && !tls13_derive_finishedkey(s, ssl_handshake_md(s), secret,
|
---|
666 | finsecret, finsecretlen)) {
|
---|
667 | /* SSLfatal() already called */
|
---|
668 | goto err;
|
---|
669 | }
|
---|
670 |
|
---|
671 | if (!s->server && label == client_early_traffic)
|
---|
672 | s->statem.enc_write_state = ENC_WRITE_STATE_WRITE_PLAIN_ALERTS;
|
---|
673 | else
|
---|
674 | s->statem.enc_write_state = ENC_WRITE_STATE_VALID;
|
---|
675 | #ifndef OPENSSL_NO_KTLS
|
---|
676 | # if defined(OPENSSL_KTLS_TLS13)
|
---|
677 | if (!(which & SSL3_CC_WRITE)
|
---|
678 | || !(which & SSL3_CC_APPLICATION)
|
---|
679 | || (s->options & SSL_OP_ENABLE_KTLS) == 0)
|
---|
680 | goto skip_ktls;
|
---|
681 |
|
---|
682 | /* ktls supports only the maximum fragment size */
|
---|
683 | if (ssl_get_max_send_fragment(s) != SSL3_RT_MAX_PLAIN_LENGTH)
|
---|
684 | goto skip_ktls;
|
---|
685 |
|
---|
686 | /* ktls does not support record padding */
|
---|
687 | if (s->record_padding_cb != NULL)
|
---|
688 | goto skip_ktls;
|
---|
689 |
|
---|
690 | /* check that cipher is supported */
|
---|
691 | if (!ktls_check_supported_cipher(s, cipher, ciph_ctx))
|
---|
692 | goto skip_ktls;
|
---|
693 |
|
---|
694 | bio = s->wbio;
|
---|
695 |
|
---|
696 | if (!ossl_assert(bio != NULL)) {
|
---|
697 | SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
|
---|
698 | goto err;
|
---|
699 | }
|
---|
700 |
|
---|
701 | /* All future data will get encrypted by ktls. Flush the BIO or skip ktls */
|
---|
702 | if (BIO_flush(bio) <= 0)
|
---|
703 | goto skip_ktls;
|
---|
704 |
|
---|
705 | /* configure kernel crypto structure */
|
---|
706 | if (!ktls_configure_crypto(s, cipher, ciph_ctx,
|
---|
707 | RECORD_LAYER_get_write_sequence(&s->rlayer),
|
---|
708 | &crypto_info, NULL, iv, key, NULL, 0))
|
---|
709 | goto skip_ktls;
|
---|
710 |
|
---|
711 | /* ktls works with user provided buffers directly */
|
---|
712 | if (BIO_set_ktls(bio, &crypto_info, which & SSL3_CC_WRITE))
|
---|
713 | ssl3_release_write_buffer(s);
|
---|
714 | skip_ktls:
|
---|
715 | # endif
|
---|
716 | #endif
|
---|
717 | ret = 1;
|
---|
718 | err:
|
---|
719 | if ((which & SSL3_CC_EARLY) != 0) {
|
---|
720 | /* We up-refed this so now we need to down ref */
|
---|
721 | ssl_evp_cipher_free(cipher);
|
---|
722 | }
|
---|
723 | OPENSSL_cleanse(key, sizeof(key));
|
---|
724 | OPENSSL_cleanse(secret, sizeof(secret));
|
---|
725 | return ret;
|
---|
726 | }
|
---|
727 |
|
---|
728 | int tls13_update_key(SSL *s, int sending)
|
---|
729 | {
|
---|
730 | /* ASCII: "traffic upd", in hex for EBCDIC compatibility */
|
---|
731 | static const unsigned char application_traffic[] = "\x74\x72\x61\x66\x66\x69\x63\x20\x75\x70\x64";
|
---|
732 | const EVP_MD *md = ssl_handshake_md(s);
|
---|
733 | size_t hashlen;
|
---|
734 | unsigned char key[EVP_MAX_KEY_LENGTH];
|
---|
735 | unsigned char *insecret, *iv;
|
---|
736 | unsigned char secret[EVP_MAX_MD_SIZE];
|
---|
737 | char *log_label;
|
---|
738 | EVP_CIPHER_CTX *ciph_ctx;
|
---|
739 | int ret = 0, l;
|
---|
740 |
|
---|
741 | if ((l = EVP_MD_get_size(md)) <= 0) {
|
---|
742 | SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
|
---|
743 | return 0;
|
---|
744 | }
|
---|
745 | hashlen = (size_t)l;
|
---|
746 |
|
---|
747 | if (s->server == sending)
|
---|
748 | insecret = s->server_app_traffic_secret;
|
---|
749 | else
|
---|
750 | insecret = s->client_app_traffic_secret;
|
---|
751 |
|
---|
752 | if (sending) {
|
---|
753 | s->statem.enc_write_state = ENC_WRITE_STATE_INVALID;
|
---|
754 | iv = s->write_iv;
|
---|
755 | ciph_ctx = s->enc_write_ctx;
|
---|
756 | RECORD_LAYER_reset_write_sequence(&s->rlayer);
|
---|
757 | } else {
|
---|
758 | iv = s->read_iv;
|
---|
759 | ciph_ctx = s->enc_read_ctx;
|
---|
760 | RECORD_LAYER_reset_read_sequence(&s->rlayer);
|
---|
761 | }
|
---|
762 |
|
---|
763 | if (!derive_secret_key_and_iv(s, sending, md,
|
---|
764 | s->s3.tmp.new_sym_enc, insecret, NULL,
|
---|
765 | application_traffic,
|
---|
766 | sizeof(application_traffic) - 1, secret, key,
|
---|
767 | iv, ciph_ctx)) {
|
---|
768 | /* SSLfatal() already called */
|
---|
769 | goto err;
|
---|
770 | }
|
---|
771 |
|
---|
772 | memcpy(insecret, secret, hashlen);
|
---|
773 |
|
---|
774 | /* Call Key log on successful traffic secret update */
|
---|
775 | log_label = s->server == sending ? SERVER_APPLICATION_N_LABEL : CLIENT_APPLICATION_N_LABEL;
|
---|
776 | if (!ssl_log_secret(s, log_label, secret, hashlen)) {
|
---|
777 | /* SSLfatal() already called */
|
---|
778 | goto err;
|
---|
779 | }
|
---|
780 |
|
---|
781 | s->statem.enc_write_state = ENC_WRITE_STATE_VALID;
|
---|
782 | ret = 1;
|
---|
783 | err:
|
---|
784 | OPENSSL_cleanse(key, sizeof(key));
|
---|
785 | OPENSSL_cleanse(secret, sizeof(secret));
|
---|
786 | return ret;
|
---|
787 | }
|
---|
788 |
|
---|
789 | int tls13_alert_code(int code)
|
---|
790 | {
|
---|
791 | /* There are 2 additional alerts in TLSv1.3 compared to TLSv1.2 */
|
---|
792 | if (code == SSL_AD_MISSING_EXTENSION || code == SSL_AD_CERTIFICATE_REQUIRED)
|
---|
793 | return code;
|
---|
794 |
|
---|
795 | return tls1_alert_code(code);
|
---|
796 | }
|
---|
797 |
|
---|
798 | int tls13_export_keying_material(SSL *s, unsigned char *out, size_t olen,
|
---|
799 | const char *label, size_t llen,
|
---|
800 | const unsigned char *context,
|
---|
801 | size_t contextlen, int use_context)
|
---|
802 | {
|
---|
803 | unsigned char exportsecret[EVP_MAX_MD_SIZE];
|
---|
804 | /* ASCII: "exporter", in hex for EBCDIC compatibility */
|
---|
805 | static const unsigned char exporterlabel[] = "\x65\x78\x70\x6F\x72\x74\x65\x72";
|
---|
806 | unsigned char hash[EVP_MAX_MD_SIZE], data[EVP_MAX_MD_SIZE];
|
---|
807 | const EVP_MD *md = ssl_handshake_md(s);
|
---|
808 | EVP_MD_CTX *ctx = EVP_MD_CTX_new();
|
---|
809 | unsigned int hashsize, datalen;
|
---|
810 | int ret = 0;
|
---|
811 |
|
---|
812 | if (ctx == NULL || md == NULL || !ossl_statem_export_allowed(s))
|
---|
813 | goto err;
|
---|
814 |
|
---|
815 | if (!use_context)
|
---|
816 | contextlen = 0;
|
---|
817 |
|
---|
818 | if (EVP_DigestInit_ex(ctx, md, NULL) <= 0
|
---|
819 | || EVP_DigestUpdate(ctx, context, contextlen) <= 0
|
---|
820 | || EVP_DigestFinal_ex(ctx, hash, &hashsize) <= 0
|
---|
821 | || EVP_DigestInit_ex(ctx, md, NULL) <= 0
|
---|
822 | || EVP_DigestFinal_ex(ctx, data, &datalen) <= 0
|
---|
823 | || !tls13_hkdf_expand(s, md, s->exporter_master_secret,
|
---|
824 | (const unsigned char *)label, llen,
|
---|
825 | data, datalen, exportsecret, hashsize, 0)
|
---|
826 | || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel,
|
---|
827 | sizeof(exporterlabel) - 1, hash, hashsize,
|
---|
828 | out, olen, 0))
|
---|
829 | goto err;
|
---|
830 |
|
---|
831 | ret = 1;
|
---|
832 | err:
|
---|
833 | EVP_MD_CTX_free(ctx);
|
---|
834 | return ret;
|
---|
835 | }
|
---|
836 |
|
---|
837 | int tls13_export_keying_material_early(SSL *s, unsigned char *out, size_t olen,
|
---|
838 | const char *label, size_t llen,
|
---|
839 | const unsigned char *context,
|
---|
840 | size_t contextlen)
|
---|
841 | {
|
---|
842 | /* ASCII: "exporter", in hex for EBCDIC compatibility */
|
---|
843 | static const unsigned char exporterlabel[] = "\x65\x78\x70\x6F\x72\x74\x65\x72";
|
---|
844 | unsigned char exportsecret[EVP_MAX_MD_SIZE];
|
---|
845 | unsigned char hash[EVP_MAX_MD_SIZE], data[EVP_MAX_MD_SIZE];
|
---|
846 | const EVP_MD *md;
|
---|
847 | EVP_MD_CTX *ctx = EVP_MD_CTX_new();
|
---|
848 | unsigned int hashsize, datalen;
|
---|
849 | int ret = 0;
|
---|
850 | const SSL_CIPHER *sslcipher;
|
---|
851 |
|
---|
852 | if (ctx == NULL || !ossl_statem_export_early_allowed(s))
|
---|
853 | goto err;
|
---|
854 |
|
---|
855 | if (!s->server && s->max_early_data > 0
|
---|
856 | && s->session->ext.max_early_data == 0)
|
---|
857 | sslcipher = SSL_SESSION_get0_cipher(s->psksession);
|
---|
858 | else
|
---|
859 | sslcipher = SSL_SESSION_get0_cipher(s->session);
|
---|
860 |
|
---|
861 | md = ssl_md(s->ctx, sslcipher->algorithm2);
|
---|
862 |
|
---|
863 | /*
|
---|
864 | * Calculate the hash value and store it in |data|. The reason why
|
---|
865 | * the empty string is used is that the definition of TLS-Exporter
|
---|
866 | * is like so:
|
---|
867 | *
|
---|
868 | * TLS-Exporter(label, context_value, key_length) =
|
---|
869 | * HKDF-Expand-Label(Derive-Secret(Secret, label, ""),
|
---|
870 | * "exporter", Hash(context_value), key_length)
|
---|
871 | *
|
---|
872 | * Derive-Secret(Secret, Label, Messages) =
|
---|
873 | * HKDF-Expand-Label(Secret, Label,
|
---|
874 | * Transcript-Hash(Messages), Hash.length)
|
---|
875 | *
|
---|
876 | * Here Transcript-Hash is the cipher suite hash algorithm.
|
---|
877 | */
|
---|
878 | if (md == NULL
|
---|
879 | || EVP_DigestInit_ex(ctx, md, NULL) <= 0
|
---|
880 | || EVP_DigestUpdate(ctx, context, contextlen) <= 0
|
---|
881 | || EVP_DigestFinal_ex(ctx, hash, &hashsize) <= 0
|
---|
882 | || EVP_DigestInit_ex(ctx, md, NULL) <= 0
|
---|
883 | || EVP_DigestFinal_ex(ctx, data, &datalen) <= 0
|
---|
884 | || !tls13_hkdf_expand(s, md, s->early_exporter_master_secret,
|
---|
885 | (const unsigned char *)label, llen,
|
---|
886 | data, datalen, exportsecret, hashsize, 0)
|
---|
887 | || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel,
|
---|
888 | sizeof(exporterlabel) - 1, hash, hashsize,
|
---|
889 | out, olen, 0))
|
---|
890 | goto err;
|
---|
891 |
|
---|
892 | ret = 1;
|
---|
893 | err:
|
---|
894 | EVP_MD_CTX_free(ctx);
|
---|
895 | return ret;
|
---|
896 | }
|
---|