ISCSI.cpp@ 44232

Last change on this file since 44232 was 44232, checked in by vboxsync, 12 years ago
Storage: Fix regression introduced when adding VD_OPEN_FLAGS_SKIP_CONSISTENCY_CHECKS resulting in non working online merging of snapshots
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File size: 196.7 KB

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1	/* $Id: ISCSI.cpp 44232 2013-01-04 14:30:20Z vboxsync $ */
2	/** @file
3	* iSCSI initiator driver, VD backend.
4	*/
5
6	/*
7	* Copyright (C) 2006-2011 Oracle Corporation
8	*
9	* This file is part of VirtualBox Open Source Edition (OSE), as
10	* available from http://www.virtualbox.org. This file is free software;
11	* you can redistribute it and/or modify it under the terms of the GNU
12	* General Public License (GPL) as published by the Free Software
13	* Foundation, in version 2 as it comes in the "COPYING" file of the
14	* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
15	* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
16	*/
17
18
19	/*******************************************************************************
20	* Header Files *
21	*******************************************************************************/
22	#define LOG_GROUP LOG_GROUP_VD_ISCSI
23	#include <VBox/vd-plugin.h>
24	#include <VBox/err.h>
25
26	#include <VBox/log.h>
27	#include <iprt/alloc.h>
28	#include <iprt/assert.h>
29	#include <iprt/uuid.h>
30	#include <iprt/string.h>
31	#include <iprt/asm.h>
32	#include <iprt/thread.h>
33	#include <iprt/semaphore.h>
34	#include <iprt/md5.h>
35	#include <iprt/tcp.h>
36	#include <iprt/time.h>
37	#include <VBox/scsi.h>
38
39
40	/*******************************************************************************
41	* Defined Constants And Macros *
42	*******************************************************************************/
43
44	/** The maximum number of release log entries per image. */
45	#define MAX_LOG_REL_ERRORS 1024
46
47	/** Default port number to use for iSCSI. */
48	#define ISCSI_DEFAULT_PORT 3260
49
50
51	/** Converts a number in the range of 0 - 15 into the corresponding hex char. */
52	#define NUM_2_HEX(b) ('0' + (b) + (((b) > 9) ? 39 : 0))
53	/** Converts a hex char into the corresponding number in the range 0-15. */
54	#define HEX_2_NUM(c) (((c) <= '9') ? ((c) - '0') : (((c - 'A' + 10) & 0xf)))
55	/* Converts a base64 char into the corresponding number in the range 0-63. */
56	#define B64_2_NUM(c) ((c >= 'A' && c <= 'Z') ? (c - 'A') : (c >= 'a' && c <= 'z') ? (c - 'a' + 26) : (c >= '0' && c <= '9') ? (c - '0' + 52) : (c == '+') ? 62 : (c == '/') ? 63 : -1)
57
58
59	/** Minimum CHAP_MD5 challenge length in bytes. */
60	#define CHAP_MD5_CHALLENGE_MIN 16
61	/** Maximum CHAP_MD5 challenge length in bytes. */
62	#define CHAP_MD5_CHALLENGE_MAX 24
63
64
65	/**
66	* SCSI peripheral device type. */
67	typedef enum SCSIDEVTYPE
68	{
69	/** direct-access device. */
70	SCSI_DEVTYPE_DISK = 0,
71	/** sequential-access device. */
72	SCSI_DEVTYPE_TAPE,
73	/** printer device. */
74	SCSI_DEVTYPE_PRINTER,
75	/** processor device. */
76	SCSI_DEVTYPE_PROCESSOR,
77	/** write-once device. */
78	SCSI_DEVTYPE_WORM,
79	/** CD/DVD device. */
80	SCSI_DEVTYPE_CDROM,
81	/** scanner device. */
82	SCSI_DEVTYPE_SCANNER,
83	/** optical memory device. */
84	SCSI_DEVTYPE_OPTICAL,
85	/** medium changer. */
86	SCSI_DEVTYPE_CHANGER,
87	/** communications device. */
88	SCSI_DEVTYPE_COMMUNICATION,
89	/** storage array controller device. */
90	SCSI_DEVTYPE_RAIDCTL = 0x0c,
91	/** enclosure services device. */
92	SCSI_DEVTYPE_ENCLOSURE,
93	/** simplified direct-access device. */
94	SCSI_DEVTYPE_SIMPLEDISK,
95	/** optical card reader/writer device. */
96	SCSI_DEVTYPE_OCRW,
97	/** bridge controller device. */
98	SCSI_DEVTYPE_BRIDGE,
99	/** object-based storage device. */
100	SCSI_DEVTYPE_OSD
101	} SCSIDEVTYPE;
102
103	/** Mask for extracting the SCSI device type out of the first byte of the INQUIRY response. */
104	#define SCSI_DEVTYPE_MASK 0x1f
105
106	/** Mask to extract the CmdQue bit out of the seventh byte of the INQUIRY response. */
107	#define SCSI_INQUIRY_CMDQUE_MASK 0x02
108
109	/** Maximum PDU payload size we can handle in one piece. Greater or equal than
110	* s_iscsiConfigDefaultWriteSplit. */
111	#define ISCSI_DATA_LENGTH_MAX _256K
112
113	/** Maximum PDU size we can handle in one piece. */
114	#define ISCSI_RECV_PDU_BUFFER_SIZE (ISCSI_DATA_LENGTH_MAX + ISCSI_BHS_SIZE)
115
116
117	/** Version of the iSCSI standard which this initiator driver can handle. */
118	#define ISCSI_MY_VERSION 0
119
120
121	/** Length of ISCSI basic header segment. */
122	#define ISCSI_BHS_SIZE 48
123
124
125	/** Reserved task tag value. */
126	#define ISCSI_TASK_TAG_RSVD 0xffffffff
127
128
129	/**
130	* iSCSI opcodes. */
131	typedef enum ISCSIOPCODE
132	{
133	/** NOP-Out. */
134	ISCSIOP_NOP_OUT = 0x00000000,
135	/** SCSI command. */
136	ISCSIOP_SCSI_CMD = 0x01000000,
137	/** SCSI task management request. */
138	ISCSIOP_SCSI_TASKMGMT_REQ = 0x02000000,
139	/** Login request. */
140	ISCSIOP_LOGIN_REQ = 0x03000000,
141	/** Text request. */
142	ISCSIOP_TEXT_REQ = 0x04000000,
143	/** SCSI Data-Out. */
144	ISCSIOP_SCSI_DATA_OUT = 0x05000000,
145	/** Logout request. */
146	ISCSIOP_LOGOUT_REQ = 0x06000000,
147	/** SNACK request. */
148	ISCSIOP_SNACK_REQ = 0x10000000,
149
150	/** NOP-In. */
151	ISCSIOP_NOP_IN = 0x20000000,
152	/** SCSI response. */
153	ISCSIOP_SCSI_RES = 0x21000000,
154	/** SCSI Task Management response. */
155	ISCSIOP_SCSI_TASKMGMT_RES = 0x22000000,
156	/** Login response. */
157	ISCSIOP_LOGIN_RES = 0x23000000,
158	/** Text response. */
159	ISCSIOP_TEXT_RES = 0x24000000,
160	/** SCSI Data-In. */
161	ISCSIOP_SCSI_DATA_IN = 0x25000000,
162	/** Logout response. */
163	ISCSIOP_LOGOUT_RES = 0x26000000,
164	/** Ready To Transfer (R2T). */
165	ISCSIOP_R2T = 0x31000000,
166	/** Asynchronous message. */
167	ISCSIOP_ASYN_MSG = 0x32000000,
168	/** Reject. */
169	ISCSIOP_REJECT = 0x3f000000
170	} ISCSIOPCODE;
171
172	/** Mask for extracting the iSCSI opcode out of the first header word. */
173	#define ISCSIOP_MASK 0x3f000000
174
175
176	/** ISCSI BHS word 0: Request should be processed immediately. */
177	#define ISCSI_IMMEDIATE_DELIVERY_BIT 0x40000000
178
179	/** ISCSI BHS word 0: This is the final PDU for this request/response. */
180	#define ISCSI_FINAL_BIT 0x00800000
181	/** ISCSI BHS word 0: Mask for extracting the CSG. */
182	#define ISCSI_CSG_MASK 0x000c0000
183	/** ISCSI BHS word 0: Shift offset for extracting the CSG. */
184	#define ISCSI_CSG_SHIFT 18
185	/** ISCSI BHS word 0: Mask for extracting the NSG. */
186	#define ISCSI_NSG_MASK 0x00030000
187	/** ISCSI BHS word 0: Shift offset for extracting the NSG. */
188	#define ISCSI_NSG_SHIFT 16
189
190	/** ISCSI BHS word 0: task attribute untagged */
191	#define ISCSI_TASK_ATTR_UNTAGGED 0x00000000
192	/** ISCSI BHS word 0: task attribute simple */
193	#define ISCSI_TASK_ATTR_SIMPLE 0x00010000
194	/** ISCSI BHS word 0: task attribute ordered */
195	#define ISCSI_TASK_ATTR_ORDERED 0x00020000
196	/** ISCSI BHS word 0: task attribute head of queue */
197	#define ISCSI_TASK_ATTR_HOQ 0x00030000
198	/** ISCSI BHS word 0: task attribute ACA */
199	#define ISCSI_TASK_ATTR_ACA 0x00040000
200
201	/** ISCSI BHS word 0: transit to next login phase. */
202	#define ISCSI_TRANSIT_BIT 0x00800000
203	/** ISCSI BHS word 0: continue with login negotiation. */
204	#define ISCSI_CONTINUE_BIT 0x00400000
205
206	/** ISCSI BHS word 0: residual underflow. */
207	#define ISCSI_RESIDUAL_UNFL_BIT 0x00020000
208	/** ISCSI BHS word 0: residual overflow. */
209	#define ISCSI_RESIDUAL_OVFL_BIT 0x00040000
210	/** ISCSI BHS word 0: Bidirectional read residual underflow. */
211	#define ISCSI_BI_READ_RESIDUAL_UNFL_BIT 0x00080000
212	/** ISCSI BHS word 0: Bidirectional read residual overflow. */
213	#define ISCSI_BI_READ_RESIDUAL_OVFL_BIT 0x00100000
214
215	/** ISCSI BHS word 0: SCSI response mask. */
216	#define ISCSI_SCSI_RESPONSE_MASK 0x0000ff00
217	/** ISCSI BHS word 0: SCSI status mask. */
218	#define ISCSI_SCSI_STATUS_MASK 0x000000ff
219
220	/** ISCSI BHS word 0: response includes status. */
221	#define ISCSI_STATUS_BIT 0x00010000
222
223	/** Maximum number of scatter/gather segments needed to send a PDU. */
224	#define ISCSI_SG_SEGMENTS_MAX 4
225
226	/** Number of entries in the command table. */
227	#define ISCSI_CMD_WAITING_ENTRIES 32
228
229	/**
230	* iSCSI login status class. */
231	typedef enum ISCSILOGINSTATUSCLASS
232	{
233	/** Success. */
234	ISCSI_LOGIN_STATUS_CLASS_SUCCESS = 0,
235	/** Redirection. */
236	ISCSI_LOGIN_STATUS_CLASS_REDIRECTION,
237	/** Initiator error. */
238	ISCSI_LOGIN_STATUS_CLASS_INITIATOR_ERROR,
239	/** Target error. */
240	ISCSI_LOGIN_STATUS_CLASS_TARGET_ERROR
241	} ISCSILOGINSTATUSCLASS;
242
243
244	/**
245	* iSCSI connection state. */
246	typedef enum ISCSISTATE
247	{
248	/** Not having a connection/session at all. */
249	ISCSISTATE_FREE,
250	/** Currently trying to login. */
251	ISCSISTATE_IN_LOGIN,
252	/** Normal operation, corresponds roughly to the Full Feature Phase. */
253	ISCSISTATE_NORMAL,
254	/** Currently trying to logout. */
255	ISCSISTATE_IN_LOGOUT
256	} ISCSISTATE;
257
258	/**
259	* iSCSI PDU send flags (and maybe more in the future). */
260	typedef enum ISCSIPDUFLAGS
261	{
262	/** No special flags */
263	ISCSIPDU_DEFAULT = 0,
264	/** Do not attempt to re-attach to the target if the connection is lost */
265	ISCSIPDU_NO_REATTACH = RT_BIT(1)
266	} ISCSIPDUFLAGS;
267
268
269	/*******************************************************************************
270	* Structures and Typedefs *
271	*******************************************************************************/
272
273	/**
274	* iSCSI login negotiation parameter
275	*/
276	typedef struct ISCSIPARAMETER
277	{
278	/** Name of the parameter. */
279	const char *pszParamName;
280	/** Value of the parameter. */
281	const char *pszParamValue;
282	/** Length of the binary parameter. 0=zero-terminated string. */
283	size_t cbParamValue;
284	} ISCSIPARAMETER;
285
286
287	/**
288	* iSCSI Response PDU buffer (scatter).
289	*/
290	typedef struct ISCSIRES
291	{
292	/** Length of PDU segment. */
293	size_t cbSeg;
294	/** Pointer to PDU segment. */
295	void *pvSeg;
296	} ISCSIRES;
297	/** Pointer to an iSCSI Response PDU buffer. */
298	typedef ISCSIRES *PISCSIRES;
299	/** Pointer to a const iSCSI Response PDU buffer. */
300	typedef ISCSIRES const *PCISCSIRES;
301
302
303	/**
304	* iSCSI Request PDU buffer (gather).
305	*/
306	typedef struct ISCSIREQ
307	{
308	/** Length of PDU segment in bytes. */
309	size_t cbSeg;
310	/** Pointer to PDU segment. */
311	const void *pcvSeg;
312	} ISCSIREQ;
313	/** Pointer to an iSCSI Request PDU buffer. */
314	typedef ISCSIREQ *PISCSIREQ;
315	/** Pointer to a const iSCSI Request PDU buffer. */
316	typedef ISCSIREQ const *PCISCSIREQ;
317
318
319	/**
320	* SCSI transfer directions.
321	*/
322	typedef enum SCSIXFER
323	{
324	SCSIXFER_NONE = 0,
325	SCSIXFER_TO_TARGET,
326	SCSIXFER_FROM_TARGET,
327	SCSIXFER_TO_FROM_TARGET
328	} SCSIXFER, *PSCSIXFER;
329
330	/** Forward declaration. */
331	typedef struct ISCSIIMAGE *PISCSIIMAGE;
332
333	/**
334	* SCSI request structure.
335	*/
336	typedef struct SCSIREQ
337	{
338	/** Transfer direction. */
339	SCSIXFER enmXfer;
340	/** Length of command block. */
341	size_t cbCDB;
342	/** Length of Initiator2Target data buffer. */
343	size_t cbI2TData;
344	/** Length of Target2Initiator data buffer. */
345	size_t cbT2IData;
346	/** Length of sense buffer
347	* This contains the number of sense bytes received upon completion. */
348	size_t cbSense;
349	/** Completion status of the command. */
350	uint8_t status;
351	/** Pointer to command block. */
352	void *pvCDB;
353	/** Pointer to sense buffer. */
354	void *pvSense;
355	/** Pointer to the Initiator2Target S/G list. */
356	PRTSGSEG paI2TSegs;
357	/** Number of entries in the I2T S/G list. */
358	unsigned cI2TSegs;
359	/** Pointer to the Target2Initiator S/G list. */
360	PRTSGSEG paT2ISegs;
361	/** Number of entries in the T2I S/G list. */
362	unsigned cT2ISegs;
363	/** S/G buffer for the target to initiator bits. */
364	RTSGBUF SgBufT2I;
365	} SCSIREQ, *PSCSIREQ;
366
367	/**
368	* Async request structure holding all necessary data for
369	* request processing.
370	*/
371	typedef struct SCSIREQASYNC
372	{
373	/** I/O context associated with this request. */
374	PVDIOCTX pIoCtx;
375	/** Pointer to the SCSI request structure. */
376	PSCSIREQ pScsiReq;
377	/** The CDB. */
378	uint8_t abCDB[16];
379	/** The sense buffer. */
380	uint8_t abSense[96];
381	/** Status code to return if we got sense data. */
382	int rcSense;
383	/** Number of retries if the command completes with sense
384	* data before we return with an error.
385	*/
386	unsigned cSenseRetries;
387	/** The number of entries in the I2T S/G list. */
388	unsigned cI2TSegs;
389	/** The number of entries in the T2I S/G list. */
390	unsigned cT2ISegs;
391	/** The S/G list - variable in size.
392	* This array holds both the I2T and T2I segments.
393	* The I2T segments are first and the T2I are second.
394	*/
395	RTSGSEG aSegs[1];
396	} SCSIREQASYNC, *PSCSIREQASYNC;
397
398	typedef enum ISCSICMDTYPE
399	{
400	/** Process a SCSI request. */
401	ISCSICMDTYPE_REQ = 0,
402	/** Call a function in the I/O thread. */
403	ISCSICMDTYPE_EXEC,
404	/** Usual 32bit hack. */
405	ISCSICMDTYPE_32BIT_HACK = 0x7fffffff
406	} ISCSICMDTYPE;
407
408
409	/** The command completion function. */
410	typedef DECLCALLBACK(void) FNISCSICMDCOMPLETED(PISCSIIMAGE pImage, int rcReq, void *pvUser);
411	/** Pointer to a command completion function. */
412	typedef FNISCSICMDCOMPLETED *PFNISCSICMDCOMPLETED;
413
414	/** The command execution function. */
415	typedef DECLCALLBACK(int) FNISCSIEXEC(void *pvUser);
416	/** Pointer to a command execution function. */
417	typedef FNISCSIEXEC *PFNISCSIEXEC;
418
419	/**
420	* Structure used to complete a synchronous request.
421	*/
422	typedef struct ISCSICMDSYNC
423	{
424	/** Event semaphore to wakeup the waiting thread. */
425	RTSEMEVENT EventSem;
426	/** Status code of the command. */
427	int rcCmd;
428	} ISCSICMDSYNC, *PISCSICMDSYNC;
429
430	/**
431	* iSCSI command.
432	* Used to forward requests to the I/O thread
433	* if existing.
434	*/
435	typedef struct ISCSICMD
436	{
437	/** Next one in the list. */
438	struct ISCSICMD *pNext;
439	/** Assigned ITT. */
440	uint32_t Itt;
441	/** Completion callback. */
442	PFNISCSICMDCOMPLETED pfnComplete;
443	/** Opaque user data. */
444	void *pvUser;
445	/** Command to execute. */
446	ISCSICMDTYPE enmCmdType;
447	/** Command type dependent data. */
448	union
449	{
450	/** Process a SCSI request. */
451	struct
452	{
453	/** The SCSI request to process. */
454	PSCSIREQ pScsiReq;
455	} ScsiReq;
456	/** Call a function in the I/O thread. */
457	struct
458	{
459	/** The method to execute. */
460	PFNISCSIEXEC pfnExec;
461	/** User data. */
462	void *pvUser;
463	} Exec;
464	} CmdType;
465	} ISCSICMD, *PISCSICMD;
466
467	/**
468	* Send iSCSI PDU.
469	* Contains all necessary data to send a PDU.
470	*/
471	typedef struct ISCSIPDUTX
472	{
473	/** Pointer to the next PDu to send. */
474	struct ISCSIPDUTX *pNext;
475	/** The BHS. */
476	uint32_t aBHS[12];
477	/** Assigned CmdSN for this PDU. */
478	uint32_t CmdSN;
479	/** The S/G buffer used for sending. */
480	RTSGBUF SgBuf;
481	/** Number of bytes to send until the PDU completed. */
482	size_t cbSgLeft;
483	/** The iSCSI command this PDU belongs to. */
484	PISCSICMD pIScsiCmd;
485	/** Number of segments in the request segments array. */
486	unsigned cISCSIReq;
487	/** The request segments - variable in size. */
488	RTSGSEG aISCSIReq[1];
489	} ISCSIPDUTX, *PISCSIPDUTX;
490
491	/**
492	* Block driver instance data.
493	*/
494	typedef struct ISCSIIMAGE
495	{
496	/** Pointer to the filename (location). Not really used. */
497	const char *pszFilename;
498	/** Pointer to the initiator name. */
499	char *pszInitiatorName;
500	/** Pointer to the target name. */
501	char *pszTargetName;
502	/** Pointer to the target address. */
503	char *pszTargetAddress;
504	/** Pointer to the user name for authenticating the Initiator. */
505	char *pszInitiatorUsername;
506	/** Pointer to the secret for authenticating the Initiator. */
507	uint8_t *pbInitiatorSecret;
508	/** Length of the secret for authenticating the Initiator. */
509	size_t cbInitiatorSecret;
510	/** Pointer to the user name for authenticating the Target. */
511	char *pszTargetUsername;
512	/** Pointer to the secret for authenticating the Initiator. */
513	uint8_t *pbTargetSecret;
514	/** Length of the secret for authenticating the Initiator. */
515	size_t cbTargetSecret;
516	/** Limit for iSCSI writes, essentially limiting the amount of data
517	* written in a single write. This is negotiated with the target, so
518	* the actual size might be smaller. */
519	uint32_t cbWriteSplit;
520	/** Initiator session identifier. */
521	uint64_t ISID;
522	/** SCSI Logical Unit Number. */
523	uint64_t LUN;
524	/** Pointer to the per-disk VD interface list. */
525	PVDINTERFACE pVDIfsDisk;
526	/** Pointer to the per-image VD interface list. */
527	PVDINTERFACE pVDIfsImage;
528	/** Error interface. */
529	PVDINTERFACEERROR pIfError;
530	/** Config interface. */
531	PVDINTERFACECONFIG pIfConfig;
532	/** I/O interface. */
533	PVDINTERFACEIOINT pIfIo;
534	/** TCP network stack interface. */
535	PVDINTERFACETCPNET pIfNet;
536	/** Image open flags. */
537	unsigned uOpenFlags;
538	/** Number of re-login retries when a connection fails. */
539	uint32_t cISCSIRetries;
540	/** Sector size on volume. */
541	uint32_t cbSector;
542	/** Size of volume in sectors. */
543	uint64_t cVolume;
544	/** Total volume size in bytes. Easier than multiplying the above values all the time. */
545	uint64_t cbSize;
546
547	/** Negotiated maximum data length when sending to target. */
548	uint32_t cbSendDataLength;
549	/** Negotiated maximum data length when receiving from target. */
550	uint32_t cbRecvDataLength;
551
552	/** Current state of the connection/session. */
553	ISCSISTATE state;
554	/** Flag whether the first Login Response PDU has been seen. */
555	bool FirstRecvPDU;
556	/** Initiator Task Tag of the last iSCSI request PDU. */
557	uint32_t ITT;
558	/** Sequence number of the last command. */
559	uint32_t CmdSN;
560	/** Sequence number of the next command expected by the target. */
561	uint32_t ExpCmdSN;
562	/** Maximum sequence number accepted by the target (determines size of window). */
563	uint32_t MaxCmdSN;
564	/** Expected sequence number of next status. */
565	uint32_t ExpStatSN;
566	/** Currently active request. */
567	PISCSIREQ paCurrReq;
568	/** Segment number of currently active request. */
569	uint32_t cnCurrReq;
570	/** Pointer to receive PDU buffer. (Freed by RT) */
571	void *pvRecvPDUBuf;
572	/** Length of receive PDU buffer. */
573	size_t cbRecvPDUBuf;
574	/** Mutex protecting against concurrent use from several threads. */
575	RTSEMMUTEX Mutex;
576
577	/** Pointer to the target hostname. */
578	char *pszHostname;
579	/** Port to use on the target host. */
580	uint32_t uPort;
581	/** Socket handle of the TCP connection. */
582	VDSOCKET Socket;
583	/** Timeout for read operations on the TCP connection (in milliseconds). */
584	uint32_t uReadTimeout;
585	/** Flag whether to automatically generate the initiator name. */
586	bool fAutomaticInitiatorName;
587	/** Flag whether to use the host IP stack or DevINIP. */
588	bool fHostIP;
589
590	/** Head of request queue */
591	PISCSICMD pScsiReqQueue;
592	/** Mutex protecting the request queue from concurrent access. */
593	RTSEMMUTEX MutexReqQueue;
594	/** I/O thread. */
595	RTTHREAD hThreadIo;
596	/** Flag whether the thread should be still running. */
597	volatile bool fRunning;
598	/* Flag whether the target supports command queuing. */
599	bool fCmdQueuingSupported;
600	/** Flag whether extended select is supported. */
601	bool fExtendedSelectSupported;
602	/** Padding used for aligning the PDUs. */
603	uint8_t aPadding[4];
604	/** Socket events to poll for. */
605	uint32_t fPollEvents;
606	/** Number of bytes to read to complete the current PDU. */
607	size_t cbRecvPDUResidual;
608	/** Current position in the PDU buffer. */
609	uint8_t *pbRecvPDUBufCur;
610	/** Flag whether we are currently reading the BHS. */
611	bool fRecvPDUBHS;
612	/** List of PDUs waiting to get transmitted. */
613	PISCSIPDUTX pIScsiPDUTxHead;
614	/** Tail of PDUs waiting to get transmitted. */
615	PISCSIPDUTX pIScsiPDUTxTail;
616	/** PDU we are currently transmitting. */
617	PISCSIPDUTX pIScsiPDUTxCur;
618	/** Number of commands waiting for an answer from the target.
619	* Used for timeout handling for poll.
620	*/
621	unsigned cCmdsWaiting;
622	/** Table of commands waiting for a response from the target. */
623	PISCSICMD aCmdsWaiting[ISCSI_CMD_WAITING_ENTRIES];
624
625	/** Release log counter. */
626	unsigned cLogRelErrors;
627	} ISCSIIMAGE;
628
629
630	/*******************************************************************************
631	* Static Variables *
632	*******************************************************************************/
633
634	/** Default initiator basename. */
635	static const char *s_iscsiDefaultInitiatorBasename = "iqn.2009-08.com.sun.virtualbox.initiator";
636
637	/** Default LUN. */
638	static const char *s_iscsiConfigDefaultLUN = "0";
639
640	/** Default timeout, 10 seconds. */
641	static const char *s_iscsiConfigDefaultTimeout = "10000";
642
643	/** Default write split value, less or equal to ISCSI_DATA_LENGTH_MAX. */
644	static const char *s_iscsiConfigDefaultWriteSplit = "262144";
645
646	/** Default host IP stack. */
647	static const char *s_iscsiConfigDefaultHostIPStack = "1";
648
649	/** Description of all accepted config parameters. */
650	static const VDCONFIGINFO s_iscsiConfigInfo[] =
651	{
652	{ "TargetName", NULL, VDCFGVALUETYPE_STRING, VD_CFGKEY_MANDATORY },
653	/* LUN is defined of string type to handle the "enc" prefix. */
654	{ "LUN", s_iscsiConfigDefaultLUN, VDCFGVALUETYPE_STRING, VD_CFGKEY_MANDATORY },
655	{ "TargetAddress", NULL, VDCFGVALUETYPE_STRING, VD_CFGKEY_MANDATORY },
656	{ "InitiatorName", NULL, VDCFGVALUETYPE_STRING, 0 },
657	{ "InitiatorUsername", NULL, VDCFGVALUETYPE_STRING, 0 },
658	{ "InitiatorSecret", NULL, VDCFGVALUETYPE_BYTES, 0 },
659	{ "TargetUsername", NULL, VDCFGVALUETYPE_STRING, VD_CFGKEY_EXPERT },
660	{ "TargetSecret", NULL, VDCFGVALUETYPE_BYTES, VD_CFGKEY_EXPERT },
661	{ "WriteSplit", s_iscsiConfigDefaultWriteSplit, VDCFGVALUETYPE_INTEGER, VD_CFGKEY_EXPERT },
662	{ "Timeout", s_iscsiConfigDefaultTimeout, VDCFGVALUETYPE_INTEGER, VD_CFGKEY_EXPERT },
663	{ "HostIPStack", s_iscsiConfigDefaultHostIPStack, VDCFGVALUETYPE_INTEGER, VD_CFGKEY_EXPERT },
664	{ NULL, NULL, VDCFGVALUETYPE_INTEGER, 0 }
665	};
666
667	/*******************************************************************************
668	* Internal Functions *
669	*******************************************************************************/
670
671	/* iSCSI low-level functions (only to be used from the iSCSI high-level functions). */
672	static uint32_t iscsiNewITT(PISCSIIMAGE pImage);
673	static int iscsiSendPDU(PISCSIIMAGE pImage, PISCSIREQ paReq, uint32_t cnReq, uint32_t uFlags);
674	static int iscsiRecvPDU(PISCSIIMAGE pImage, uint32_t itt, PISCSIRES paRes, uint32_t cnRes);
675	static int iscsiRecvPDUAsync(PISCSIIMAGE pImage);
676	static int iscsiSendPDUAsync(PISCSIIMAGE pImage);
677	static int iscsiValidatePDU(PISCSIRES paRes, uint32_t cnRes);
678	static int iscsiRecvPDUProcess(PISCSIIMAGE pImage, PISCSIRES paRes, uint32_t cnRes);
679	static int iscsiPDUTxPrepare(PISCSIIMAGE pImage, PISCSICMD pIScsiCmd);
680	static int iscsiRecvPDUUpdateRequest(PISCSIIMAGE pImage, PISCSIRES paRes, uint32_t cnRes);
681	static void iscsiCmdComplete(PISCSIIMAGE pImage, PISCSICMD pIScsiCmd, int rcCmd);
682	static int iscsiTextAddKeyValue(uint8_t pbBuf, size_t cbBuf, size_t pcbBufCurr, const char pcszKey, const char pcszValue, size_t cbValue);
683	static int iscsiTextGetKeyValue(const uint8_t pbBuf, size_t cbBuf, const char pcszKey, const char **ppcszValue);
684	static int iscsiStrToBinary(const char pcszValue, uint8_t pbValue, size_t *pcbValue);
685	static int iscsiUpdateParameters(PISCSIIMAGE pImage, const uint8_t *pbBuf, size_t cbBuf);
686
687	/* Serial number arithmetic comparison. */
688	static bool serial_number_less(uint32_t sn1, uint32_t sn2);
689	static bool serial_number_greater(uint32_t sn1, uint32_t sn2);
690
691	/* CHAP-MD5 functions. */
692	#ifdef IMPLEMENT_TARGET_AUTH
693	static void chap_md5_generate_challenge(uint8_t pbChallenge, size_t pcbChallenge);
694	#endif
695	static void chap_md5_compute_response(uint8_t pbResponse, uint8_t id, const uint8_t pbChallenge, size_t cbChallenge,
696	const uint8_t *pbSecret, size_t cbSecret);
697
698	/**
699	* Internal: release log wrapper limiting the number of entries.
700	*/
701	DECLINLINE(void) iscsiLogRel(PISCSIIMAGE pImage, const char *pcszFormat, ...)
702	{
703	if (pImage->cLogRelErrors++ < MAX_LOG_REL_ERRORS)
704	{
705	va_list va;
706
707	va_start(va, pcszFormat);
708	LogRel(("%N\n", pcszFormat, &va));
709	va_end(va);
710	}
711	}
712
713	DECLINLINE(bool) iscsiIsClientConnected(PISCSIIMAGE pImage)
714	{
715	return pImage->Socket != NIL_VDSOCKET
716	&& pImage->pIfNet->pfnIsClientConnected(pImage->Socket);
717	}
718
719	/**
720	* Calculates the hash for the given ITT used
721	* to look up the command in the table.
722	*/
723	DECLINLINE(uint32_t) iscsiIttHash(uint32_t Itt)
724	{
725	return Itt % ISCSI_CMD_WAITING_ENTRIES;
726	}
727
728	static PISCSICMD iscsiCmdGetFromItt(PISCSIIMAGE pImage, uint32_t Itt)
729	{
730	PISCSICMD pIScsiCmd = NULL;
731
732	pIScsiCmd = pImage->aCmdsWaiting[iscsiIttHash(Itt)];
733
734	while ( pIScsiCmd
735	&& pIScsiCmd->Itt != Itt)
736	pIScsiCmd = pIScsiCmd->pNext;
737
738	return pIScsiCmd;
739	}
740
741	static void iscsiCmdInsert(PISCSIIMAGE pImage, PISCSICMD pIScsiCmd)
742	{
743	PISCSICMD pIScsiCmdOld;
744	uint32_t idx = iscsiIttHash(pIScsiCmd->Itt);
745
746	Assert(!pIScsiCmd->pNext);
747
748	pIScsiCmdOld = pImage->aCmdsWaiting[idx];
749	pIScsiCmd->pNext = pIScsiCmdOld;
750	pImage->aCmdsWaiting[idx] = pIScsiCmd;
751	pImage->cCmdsWaiting++;
752	}
753
754	static PISCSICMD iscsiCmdRemove(PISCSIIMAGE pImage, uint32_t Itt)
755	{
756	PISCSICMD pIScsiCmd = NULL;
757	PISCSICMD pIScsiCmdPrev = NULL;
758	uint32_t idx = iscsiIttHash(Itt);
759
760	pIScsiCmd = pImage->aCmdsWaiting[idx];
761
762	while ( pIScsiCmd
763	&& pIScsiCmd->Itt != Itt)
764	{
765	pIScsiCmdPrev = pIScsiCmd;
766	pIScsiCmd = pIScsiCmd->pNext;
767	}
768
769	if (pIScsiCmd)
770	{
771	if (pIScsiCmdPrev)
772	{
773	Assert(!pIScsiCmd->pNext \|\| VALID_PTR(pIScsiCmd->pNext));
774	pIScsiCmdPrev->pNext = pIScsiCmd->pNext;
775	}
776	else
777	{
778	pImage->aCmdsWaiting[idx] = pIScsiCmd->pNext;
779	Assert(!pImage->aCmdsWaiting[idx] \|\| VALID_PTR(pImage->aCmdsWaiting[idx]));
780	}
781	pImage->cCmdsWaiting--;
782	}
783
784	return pIScsiCmd;
785	}
786
787	/**
788	* Removes all commands from the table and returns the
789	* list head
790	*
791	* @returns Pointer to the head of the command list.
792	* @param pImage iSCSI connection to use.
793	*/
794	static PISCSICMD iscsiCmdRemoveAll(PISCSIIMAGE pImage)
795	{
796	PISCSICMD pIScsiCmdHead = NULL;
797
798	for (unsigned idx = 0; idx < RT_ELEMENTS(pImage->aCmdsWaiting); idx++)
799	{
800	PISCSICMD pHead;
801	PISCSICMD pTail;
802
803	pHead = pImage->aCmdsWaiting[idx];
804	pImage->aCmdsWaiting[idx] = NULL;
805
806	if (pHead)
807	{
808	/* Get the tail. */
809	pTail = pHead;
810	while (pTail->pNext)
811	pTail = pTail->pNext;
812
813	/* Concatenate. */
814	pTail->pNext = pIScsiCmdHead;
815	pIScsiCmdHead = pHead;
816	}
817	}
818	pImage->cCmdsWaiting = 0;
819
820	return pIScsiCmdHead;
821	}
822
823	static int iscsiTransportConnect(PISCSIIMAGE pImage)
824	{
825	int rc;
826	if (!pImage->pszHostname)
827	return VERR_NET_DEST_ADDRESS_REQUIRED;
828
829	rc = pImage->pIfNet->pfnClientConnect(pImage->Socket, pImage->pszHostname, pImage->uPort);
830	if (RT_FAILURE(rc))
831	{
832	if ( rc == VERR_NET_CONNECTION_REFUSED
833	\|\| rc == VERR_NET_CONNECTION_RESET
834	\|\| rc == VERR_NET_UNREACHABLE
835	\|\| rc == VERR_NET_HOST_UNREACHABLE
836	\|\| rc == VERR_NET_CONNECTION_TIMED_OUT)
837	{
838	/* Standardize return value for no connection. */
839	rc = VERR_NET_CONNECTION_REFUSED;
840	}
841	return rc;
842	}
843
844	/* Disable Nagle algorithm, we want things to be sent immediately. */
845	pImage->pIfNet->pfnSetSendCoalescing(pImage->Socket, false);
846
847	/* Make initiator name and ISID unique on this host. */
848	RTNETADDR LocalAddr;
849	rc = pImage->pIfNet->pfnGetLocalAddress(pImage->Socket, &LocalAddr);
850	if (RT_FAILURE(rc))
851	return rc;
852	if ( LocalAddr.uPort == RTNETADDR_PORT_NA
853	\|\| LocalAddr.uPort > 65535)
854	return VERR_NET_ADDRESS_FAMILY_NOT_SUPPORTED;
855	pImage->ISID &= ~65535ULL;
856	pImage->ISID \|= LocalAddr.uPort;
857	/* Eliminate the port so that it isn't included below. */
858	LocalAddr.uPort = RTNETADDR_PORT_NA;
859	if (pImage->fAutomaticInitiatorName)
860	{
861	if (pImage->pszInitiatorName)
862	RTStrFree(pImage->pszInitiatorName);
863	RTStrAPrintf(&pImage->pszInitiatorName, "%s:01:%RTnaddr",
864	s_iscsiDefaultInitiatorBasename, &LocalAddr);
865	if (!pImage->pszInitiatorName)
866	return VERR_NO_MEMORY;
867	}
868	LogRel(("iSCSI: connect from initiator %s with source port %u\n", pImage->pszInitiatorName, pImage->ISID & 65535));
869	return VINF_SUCCESS;
870	}
871
872
873	static int iscsiTransportClose(PISCSIIMAGE pImage)
874	{
875	int rc;
876
877	LogFlowFunc(("(%s:%d)\n", pImage->pszHostname, pImage->uPort));
878	if (iscsiIsClientConnected(pImage))
879	{
880	LogRel(("iSCSI: disconnect from initiator %s with source port %u\n", pImage->pszInitiatorName, pImage->ISID & 65535));
881	rc = pImage->pIfNet->pfnClientClose(pImage->Socket);
882	}
883	else
884	rc = VINF_SUCCESS;
885	LogFlowFunc(("returns %Rrc\n", rc));
886	return rc;
887	}
888
889
890	static int iscsiTransportRead(PISCSIIMAGE pImage, PISCSIRES paResponse, unsigned int cnResponse)
891	{
892	int rc = VINF_SUCCESS;
893	unsigned int i = 0;
894	size_t cbToRead, cbActuallyRead, residual, cbSegActual = 0, cbAHSLength, cbDataLength;
895	char *pDst;
896
897	LogFlowFunc(("cnResponse=%d (%s:%d)\n", cnResponse, pImage->pszHostname, pImage->uPort));
898	if (!iscsiIsClientConnected(pImage))
899	{
900	/* Reconnecting makes no sense in this case, as there will be nothing
901	* to receive. We would just run into a timeout. */
902	rc = VERR_BROKEN_PIPE;
903	}
904
905	if (RT_SUCCESS(rc) && paResponse[0].cbSeg >= ISCSI_BHS_SIZE)
906	{
907	cbToRead = 0;
908	residual = ISCSI_BHS_SIZE; /* Do not read more than the BHS length before the true PDU length is known. */
909	cbSegActual = residual;
910	pDst = (char *)paResponse[i].pvSeg;
911	uint64_t u64Timeout = RTTimeMilliTS() + pImage->uReadTimeout;
912	do
913	{
914	int64_t cMilliesRemaining = u64Timeout - RTTimeMilliTS();
915	if (cMilliesRemaining <= 0)
916	{
917	rc = VERR_TIMEOUT;
918	break;
919	}
920	Assert(cMilliesRemaining < 1000000);
921	rc = pImage->pIfNet->pfnSelectOne(pImage->Socket, cMilliesRemaining);
922	if (RT_FAILURE(rc))
923	break;
924	rc = pImage->pIfNet->pfnRead(pImage->Socket, pDst, residual, &cbActuallyRead);
925	if (RT_FAILURE(rc))
926	break;
927	if (cbActuallyRead == 0)
928	{
929	/* The other end has closed the connection. */
930	iscsiTransportClose(pImage);
931	pImage->state = ISCSISTATE_FREE;
932	rc = VERR_NET_CONNECTION_RESET;
933	break;
934	}
935	if (cbToRead == 0)
936	{
937	/* Currently reading the BHS. */
938	residual -= cbActuallyRead;
939	pDst += cbActuallyRead;
940	if (residual <= 40)
941	{
942	/* Enough data read to figure out the actual PDU size. */
943	uint32_t word1 = RT_N2H_U32(((uint32_t *)(paResponse[0].pvSeg))[1]);
944	cbAHSLength = (word1 & 0xff000000) >> 24;
945	cbAHSLength = ((cbAHSLength - 1) \| 3) + 1; /* Add padding. */
946	cbDataLength = word1 & 0x00ffffff;
947	cbDataLength = ((cbDataLength - 1) \| 3) + 1; /* Add padding. */
948	cbToRead = residual + cbAHSLength + cbDataLength;
949	residual += paResponse[0].cbSeg - ISCSI_BHS_SIZE;
950	if (residual > cbToRead)
951	residual = cbToRead;
952	cbSegActual = ISCSI_BHS_SIZE + cbAHSLength + cbDataLength;
953	/* Check whether we are already done with this PDU (no payload). */
954	if (cbToRead == 0)
955	break;
956	}
957	}
958	else
959	{
960	cbToRead -= cbActuallyRead;
961	if (cbToRead == 0)
962	break;
963	pDst += cbActuallyRead;
964	residual -= cbActuallyRead;
965	}
966	if (residual == 0)
967	{
968	i++;
969	if (i >= cnResponse)
970	{
971	/* No space left in receive buffers. */
972	rc = VERR_BUFFER_OVERFLOW;
973	break;
974	}
975	pDst = (char *)paResponse[i].pvSeg;
976	residual = paResponse[i].cbSeg;
977	if (residual > cbToRead)
978	residual = cbToRead;
979	cbSegActual = residual;
980	}
981	LogFlowFunc(("cbToRead=%u residual=%u cbSegActual=%u cbActuallRead=%u\n",
982	cbToRead, residual, cbSegActual, cbActuallyRead));
983	} while (true);
984	}
985	else
986	{
987	if (RT_SUCCESS(rc))
988	rc = VERR_BUFFER_OVERFLOW;
989	}
990	if (RT_SUCCESS(rc))
991	{
992	paResponse[i].cbSeg = cbSegActual;
993	for (i++; i < cnResponse; i++)
994	paResponse[i].cbSeg = 0;
995	}
996
997	if (RT_UNLIKELY( RT_FAILURE(rc)
998	&& ( rc == VERR_NET_CONNECTION_RESET
999	\|\| rc == VERR_NET_CONNECTION_ABORTED
1000	\|\| rc == VERR_NET_CONNECTION_RESET_BY_PEER
1001	\|\| rc == VERR_NET_CONNECTION_REFUSED
1002	\|\| rc == VERR_BROKEN_PIPE)))
1003	{
1004	/* Standardize return value for broken connection. */
1005	rc = VERR_BROKEN_PIPE;
1006	}
1007
1008	LogFlowFunc(("returns %Rrc\n", rc));
1009	return rc;
1010	}
1011
1012
1013	static int iscsiTransportWrite(PISCSIIMAGE pImage, PISCSIREQ paRequest, unsigned int cnRequest)
1014	{
1015	int rc = VINF_SUCCESS;
1016	uint32_t pad = 0;
1017	unsigned int i;
1018
1019	LogFlowFunc(("cnRequest=%d (%s:%d)\n", cnRequest, pImage->pszHostname, pImage->uPort));
1020	if (!iscsiIsClientConnected(pImage))
1021	{
1022	/* Attempt to reconnect if the connection was previously broken. */
1023	rc = iscsiTransportConnect(pImage);
1024	}
1025
1026	if (RT_SUCCESS(rc))
1027	{
1028	/* Construct scatter/gather buffer for entire request, worst case
1029	* needs twice as many entries to allow for padding. */
1030	unsigned cBuf = 0;
1031	for (i = 0; i < cnRequest; i++)
1032	{
1033	cBuf++;
1034	if (paRequest[i].cbSeg & 3)
1035	cBuf++;
1036	}
1037	Assert(cBuf < ISCSI_SG_SEGMENTS_MAX);
1038	RTSGBUF buf;
1039	RTSGSEG aSeg[ISCSI_SG_SEGMENTS_MAX];
1040	static char aPad[4] = { 0, 0, 0, 0 };
1041	RTSgBufInit(&buf, &aSeg[0], cBuf);
1042	unsigned iBuf = 0;
1043	for (i = 0; i < cnRequest; i++)
1044	{
1045	/* Actual data chunk. */
1046	aSeg[iBuf].pvSeg = (void *)paRequest[i].pcvSeg;
1047	aSeg[iBuf].cbSeg = paRequest[i].cbSeg;
1048	iBuf++;
1049	/* Insert proper padding before the next chunk. */
1050	if (paRequest[i].cbSeg & 3)
1051	{
1052	aSeg[iBuf].pvSeg = &aPad[0];
1053	aSeg[iBuf].cbSeg = 4 - (paRequest[i].cbSeg & 3);
1054	iBuf++;
1055	}
1056	}
1057	/* Send out the request, the socket is set to send data immediately,
1058	* avoiding unnecessary delays. */
1059	rc = pImage->pIfNet->pfnSgWrite(pImage->Socket, &buf);
1060
1061	}
1062
1063	if (RT_UNLIKELY( RT_FAILURE(rc)
1064	&& ( rc == VERR_NET_CONNECTION_RESET
1065	\|\| rc == VERR_NET_CONNECTION_ABORTED
1066	\|\| rc == VERR_NET_CONNECTION_RESET_BY_PEER
1067	\|\| rc == VERR_NET_CONNECTION_REFUSED
1068	\|\| rc == VERR_BROKEN_PIPE)))
1069	{
1070	/* Standardize return value for broken connection. */
1071	rc = VERR_BROKEN_PIPE;
1072	}
1073
1074	LogFlowFunc(("returns %Rrc\n", rc));
1075	return rc;
1076	}
1077
1078
1079	static int iscsiTransportOpen(PISCSIIMAGE pImage)
1080	{
1081	int rc = VINF_SUCCESS;
1082	size_t cbHostname = 0; /* shut up gcc */
1083	const char pcszPort = NULL; / shut up gcc */
1084	char *pszPortEnd;
1085	uint16_t uPort;
1086
1087	/* Clean up previous connection data. */
1088	iscsiTransportClose(pImage);
1089	if (pImage->pszHostname)
1090	{
1091	RTMemFree(pImage->pszHostname);
1092	pImage->pszHostname = NULL;
1093	pImage->uPort = 0;
1094	}
1095
1096	/* Locate the port number via the colon separating the hostname from the port. */
1097	if (*pImage->pszTargetAddress)
1098	{
1099	if (*pImage->pszTargetAddress != '[')
1100	{
1101	/* Normal hostname or IPv4 dotted decimal. */
1102	pcszPort = strchr(pImage->pszTargetAddress, ':');
1103	if (pcszPort != NULL)
1104	{
1105	cbHostname = pcszPort - pImage->pszTargetAddress;
1106	pcszPort++;
1107	}
1108	else
1109	cbHostname = strlen(pImage->pszTargetAddress);
1110	}
1111	else
1112	{
1113	/* IPv6 literal address. Contains colons, so skip to closing square bracket. */
1114	pcszPort = strchr(pImage->pszTargetAddress, ']');
1115	if (pcszPort != NULL)
1116	{
1117	pcszPort++;
1118	cbHostname = pcszPort - pImage->pszTargetAddress;
1119	if (*pcszPort == '\0')
1120	pcszPort = NULL;
1121	else if (*pcszPort != ':')
1122	rc = VERR_PARSE_ERROR;
1123	else
1124	pcszPort++;
1125	}
1126	else
1127	rc = VERR_PARSE_ERROR;
1128	}
1129	}
1130	else
1131	rc = VERR_PARSE_ERROR;
1132
1133	/* Now split address into hostname and port. */
1134	if (RT_SUCCESS(rc))
1135	{
1136	pImage->pszHostname = (char *)RTMemAlloc(cbHostname + 1);
1137	if (!pImage->pszHostname)
1138	rc = VERR_NO_MEMORY;
1139	else
1140	{
1141	if (pImage->pszTargetAddress[0] == '[')
1142	memcpy(pImage->pszHostname, pImage->pszTargetAddress + 1, cbHostname);
1143	else
1144	memcpy(pImage->pszHostname, pImage->pszTargetAddress, cbHostname);
1145	pImage->pszHostname[cbHostname] = '\0';
1146	if (pcszPort != NULL)
1147	{
1148	rc = RTStrToUInt16Ex(pcszPort, &pszPortEnd, 0, &uPort);
1149	/* Note that RT_SUCCESS() macro to check the rc value is not strict enough in this case. */
1150	if (rc == VINF_SUCCESS && *pszPortEnd == '\0' && uPort != 0)
1151	{
1152	pImage->uPort = uPort;
1153	}
1154	else
1155	{
1156	rc = VERR_PARSE_ERROR;
1157	}
1158	}
1159	else
1160	pImage->uPort = ISCSI_DEFAULT_PORT;
1161	}
1162	}
1163
1164	if (RT_SUCCESS(rc))
1165	{
1166	if (!iscsiIsClientConnected(pImage))
1167	rc = iscsiTransportConnect(pImage);
1168	}
1169	else
1170	{
1171	if (pImage->pszHostname)
1172	{
1173	RTMemFree(pImage->pszHostname);
1174	pImage->pszHostname = NULL;
1175	}
1176	pImage->uPort = 0;
1177	}
1178
1179	LogFlowFunc(("returns %Rrc\n", rc));
1180	return rc;
1181	}
1182
1183
1184	/**
1185	* Attach to an iSCSI target. Performs all operations necessary to enter
1186	* Full Feature Phase.
1187	*
1188	* @returns VBox status.
1189	* @param pImage The iSCSI connection state to be used.
1190	*/
1191	static int iscsiAttach(void *pvUser)
1192	{
1193	int rc;
1194	uint32_t itt;
1195	uint32_t csg, nsg, substate;
1196	uint64_t isid_tsih;
1197	uint8_t bBuf[4096]; /* Should be large enough even for large authentication values. */
1198	size_t cbBuf;
1199	bool transit;
1200	uint8_t pbChallenge[1024]; /* RFC3720 specifies this as maximum. */
1201	size_t cbChallenge = 0; /* shut up gcc */
1202	uint8_t bChapIdx;
1203	uint8_t aResponse[RTMD5HASHSIZE];
1204	uint32_t cnISCSIReq;
1205	ISCSIREQ aISCSIReq[4];
1206	uint32_t aReqBHS[12];
1207	uint32_t cnISCSIRes;
1208	ISCSIRES aISCSIRes[2];
1209	uint32_t aResBHS[12];
1210	char *pszNext;
1211	PISCSIIMAGE pImage = (PISCSIIMAGE)pvUser;
1212
1213	bool fParameterNeg = true;;
1214	pImage->cbRecvDataLength = ISCSI_DATA_LENGTH_MAX;
1215	pImage->cbSendDataLength = RT_MIN(ISCSI_DATA_LENGTH_MAX, pImage->cbWriteSplit);
1216	char szMaxDataLength[16];
1217	RTStrPrintf(szMaxDataLength, sizeof(szMaxDataLength), "%u", ISCSI_DATA_LENGTH_MAX);
1218	ISCSIPARAMETER aParameterNeg[] =
1219	{
1220	{ "HeaderDigest", "None", 0 },
1221	{ "DataDigest", "None", 0 },
1222	{ "MaxConnections", "1", 0 },
1223	{ "InitialR2T", "No", 0 },
1224	{ "ImmediateData", "Yes", 0 },
1225	{ "MaxRecvDataSegmentLength", szMaxDataLength, 0 },
1226	{ "MaxBurstLength", szMaxDataLength, 0 },
1227	{ "FirstBurstLength", szMaxDataLength, 0 },
1228	{ "DefaultTime2Wait", "0", 0 },
1229	{ "DefaultTime2Retain", "60", 0 },
1230	{ "DataPDUInOrder", "Yes", 0 },
1231	{ "DataSequenceInOrder", "Yes", 0 },
1232	{ "ErrorRecoveryLevel", "0", 0 },
1233	{ "MaxOutstandingR2T", "1", 0 }
1234	};
1235
1236	LogFlowFunc(("entering\n"));
1237
1238	Assert(pImage->state == ISCSISTATE_FREE);
1239
1240	RTSemMutexRequest(pImage->Mutex, RT_INDEFINITE_WAIT);
1241
1242	/* Make 100% sure the connection isn't reused for a new login. */
1243	iscsiTransportClose(pImage);
1244
1245	restart:
1246	if (!iscsiIsClientConnected(pImage))
1247	{
1248	rc = iscsiTransportOpen(pImage);
1249	if (RT_FAILURE(rc))
1250	goto out;
1251	}
1252
1253	pImage->state = ISCSISTATE_IN_LOGIN;
1254	pImage->ITT = 1;
1255	pImage->FirstRecvPDU = true;
1256	pImage->CmdSN = 1;
1257	pImage->ExpCmdSN = 0;
1258	pImage->MaxCmdSN = 1;
1259	pImage->ExpStatSN = 0;
1260
1261	/*
1262	* Send login request to target.
1263	*/
1264	itt = iscsiNewITT(pImage);
1265	csg = 0;
1266	nsg = 0;
1267	substate = 0;
1268	isid_tsih = pImage->ISID << 16; /* TSIH field currently always 0 */
1269
1270	do {
1271	transit = false;
1272	cbBuf = 0;
1273	/* Handle all cases with a single switch statement. */
1274	switch (csg << 8 \| substate)
1275	{
1276	case 0x0000: /* security negotiation, step 0: propose authentication. */
1277	rc = iscsiTextAddKeyValue(bBuf, sizeof(bBuf), &cbBuf, "SessionType", "Normal", 0);
1278	if (RT_FAILURE(rc))
1279	goto out;
1280	rc = iscsiTextAddKeyValue(bBuf, sizeof(bBuf), &cbBuf, "InitiatorName", pImage->pszInitiatorName, 0);
1281	if (RT_FAILURE(rc))
1282	goto out;
1283	rc = iscsiTextAddKeyValue(bBuf, sizeof(bBuf), &cbBuf, "TargetName", pImage->pszTargetName, 0);
1284	if (RT_FAILURE(rc))
1285	goto out;
1286	if (pImage->pszInitiatorUsername == NULL)
1287	{
1288	/* No authentication. Immediately switch to next phase. */
1289	rc = iscsiTextAddKeyValue(bBuf, sizeof(bBuf), &cbBuf, "AuthMethod", "None", 0);
1290	if (RT_FAILURE(rc))
1291	goto out;
1292	nsg = 1;
1293	transit = true;
1294	}
1295	else
1296	{
1297	rc = iscsiTextAddKeyValue(bBuf, sizeof(bBuf), &cbBuf, "AuthMethod", "CHAP,None", 0);
1298	if (RT_FAILURE(rc))
1299	goto out;
1300	}
1301	break;
1302	case 0x0001: /* security negotiation, step 1: propose CHAP_MD5 variant. */
1303	rc = iscsiTextAddKeyValue(bBuf, sizeof(bBuf), &cbBuf, "CHAP_A", "5", 0);
1304	if (RT_FAILURE(rc))
1305	goto out;
1306	break;
1307	case 0x0002: /* security negotiation, step 2: send authentication info. */
1308	rc = iscsiTextAddKeyValue(bBuf, sizeof(bBuf), &cbBuf, "CHAP_N", pImage->pszInitiatorUsername, 0);
1309	if (RT_FAILURE(rc))
1310	goto out;
1311	chap_md5_compute_response(aResponse, bChapIdx, pbChallenge, cbChallenge,
1312	pImage->pbInitiatorSecret, pImage->cbInitiatorSecret);
1313	rc = iscsiTextAddKeyValue(bBuf, sizeof(bBuf), &cbBuf, "CHAP_R", (const char *)aResponse, RTMD5HASHSIZE);
1314	if (RT_FAILURE(rc))
1315	goto out;
1316	nsg = 1;
1317	transit = true;
1318	break;
1319	case 0x0100: /* login operational negotiation, step 0: set parameters. */
1320	if (fParameterNeg)
1321	{
1322	for (unsigned i = 0; i < RT_ELEMENTS(aParameterNeg); i++)
1323	{
1324	rc = iscsiTextAddKeyValue(bBuf, sizeof(bBuf), &cbBuf,
1325	aParameterNeg[i].pszParamName,
1326	aParameterNeg[i].pszParamValue,
1327	aParameterNeg[i].cbParamValue);
1328	if (RT_FAILURE(rc))
1329	goto out;
1330	}
1331	fParameterNeg = false;
1332	}
1333
1334	nsg = 3;
1335	transit = true;
1336	break;
1337	case 0x0300: /* full feature phase. */
1338	default:
1339	/* Should never come here. */
1340	AssertMsgFailed(("send: Undefined login state %d substate %d\n", csg, substate));
1341	break;
1342	}
1343
1344	aReqBHS[0] = RT_H2N_U32( ISCSI_IMMEDIATE_DELIVERY_BIT
1345	\| (csg << ISCSI_CSG_SHIFT)
1346	\| (transit ? (nsg << ISCSI_NSG_SHIFT \| ISCSI_TRANSIT_BIT) : 0)
1347	\| ISCSI_MY_VERSION /* Minimum version. */
1348	\| (ISCSI_MY_VERSION << 8) /* Maximum version. */
1349	\| ISCSIOP_LOGIN_REQ); /* C=0 */
1350	aReqBHS[1] = RT_H2N_U32((uint32_t)cbBuf); /* TotalAHSLength=0 */
1351	aReqBHS[2] = RT_H2N_U32(isid_tsih >> 32);
1352	aReqBHS[3] = RT_H2N_U32(isid_tsih & 0xffffffff);
1353	aReqBHS[4] = itt;
1354	aReqBHS[5] = RT_H2N_U32(1 << 16); /* CID=1,reserved */
1355	aReqBHS[6] = RT_H2N_U32(pImage->CmdSN);
1356	aReqBHS[7] = RT_H2N_U32(pImage->ExpStatSN);
1357	aReqBHS[8] = 0; /* reserved */
1358	aReqBHS[9] = 0; /* reserved */
1359	aReqBHS[10] = 0; /* reserved */
1360	aReqBHS[11] = 0; /* reserved */
1361
1362	cnISCSIReq = 0;
1363	aISCSIReq[cnISCSIReq].pcvSeg = aReqBHS;
1364	aISCSIReq[cnISCSIReq].cbSeg = sizeof(aReqBHS);
1365	cnISCSIReq++;
1366
1367	aISCSIReq[cnISCSIReq].pcvSeg = bBuf;
1368	aISCSIReq[cnISCSIReq].cbSeg = cbBuf;
1369	cnISCSIReq++;
1370
1371	rc = iscsiSendPDU(pImage, aISCSIReq, cnISCSIReq, ISCSIPDU_NO_REATTACH);
1372	if (RT_SUCCESS(rc))
1373	{
1374	ISCSIOPCODE cmd;
1375	ISCSILOGINSTATUSCLASS loginStatusClass;
1376
1377	cnISCSIRes = 0;
1378	aISCSIRes[cnISCSIRes].pvSeg = aResBHS;
1379	aISCSIRes[cnISCSIRes].cbSeg = sizeof(aResBHS);
1380	cnISCSIRes++;
1381	aISCSIRes[cnISCSIRes].pvSeg = bBuf;
1382	aISCSIRes[cnISCSIRes].cbSeg = sizeof(bBuf);
1383	cnISCSIRes++;
1384
1385	rc = iscsiRecvPDU(pImage, itt, aISCSIRes, cnISCSIRes);
1386	if (RT_FAILURE(rc))
1387	break;
1388	/** @todo collect partial login responses with Continue bit set. */
1389	Assert(aISCSIRes[0].pvSeg == aResBHS);
1390	Assert(aISCSIRes[0].cbSeg >= ISCSI_BHS_SIZE);
1391	Assert((RT_N2H_U32(aResBHS[0]) & ISCSI_CONTINUE_BIT) == 0);
1392
1393	cmd = (ISCSIOPCODE)(RT_N2H_U32(aResBHS[0]) & ISCSIOP_MASK);
1394	if (cmd == ISCSIOP_LOGIN_RES)
1395	{
1396	if ((RT_N2H_U32(aResBHS[0]) & 0xff) != ISCSI_MY_VERSION)
1397	{
1398	iscsiTransportClose(pImage);
1399	rc = VERR_PARSE_ERROR;
1400	break; /* Give up immediately, as a RFC violation in version fields is very serious. */
1401	}
1402
1403	loginStatusClass = (ISCSILOGINSTATUSCLASS)(RT_N2H_U32(aResBHS[9]) >> 24);
1404	switch (loginStatusClass)
1405	{
1406	case ISCSI_LOGIN_STATUS_CLASS_SUCCESS:
1407	uint32_t targetCSG;
1408	uint32_t targetNSG;
1409	bool targetTransit;
1410
1411	if (pImage->FirstRecvPDU)
1412	{
1413	pImage->FirstRecvPDU = false;
1414	pImage->ExpStatSN = RT_N2H_U32(aResBHS[6]) + 1;
1415	}
1416
1417	targetCSG = (RT_N2H_U32(aResBHS[0]) & ISCSI_CSG_MASK) >> ISCSI_CSG_SHIFT;
1418	targetNSG = (RT_N2H_U32(aResBHS[0]) & ISCSI_NSG_MASK) >> ISCSI_NSG_SHIFT;
1419	targetTransit = !!(RT_N2H_U32(aResBHS[0]) & ISCSI_TRANSIT_BIT);
1420
1421	/* Handle all cases with a single switch statement. */
1422	switch (csg << 8 \| substate)
1423	{
1424	case 0x0000: /* security negotiation, step 0: receive final authentication. */
1425	rc = iscsiUpdateParameters(pImage, bBuf, aISCSIRes[1].cbSeg);
1426	if (RT_FAILURE(rc))
1427	break;
1428
1429	const char *pcszAuthMethod;
1430
1431	rc = iscsiTextGetKeyValue(bBuf, aISCSIRes[1].cbSeg, "AuthMethod", &pcszAuthMethod);
1432	if (RT_FAILURE(rc))
1433	{
1434	rc = VERR_PARSE_ERROR;
1435	break;
1436	}
1437	if (strcmp(pcszAuthMethod, "None") == 0)
1438	{
1439	/* Authentication offered, but none required. Skip to operational parameters. */
1440	csg = 1;
1441	nsg = 1;
1442	transit = true;
1443	substate = 0;
1444	break;
1445	}
1446	else if (strcmp(pcszAuthMethod, "CHAP") == 0 && targetNSG == 0 && !targetTransit)
1447	{
1448	/* CHAP authentication required, continue with next substate. */
1449	substate++;
1450	break;
1451	}
1452
1453	/* Unknown auth method or login response PDU headers incorrect. */
1454	rc = VERR_PARSE_ERROR;
1455	break;
1456	case 0x0001: /* security negotiation, step 1: receive final CHAP variant and challenge. */
1457	rc = iscsiUpdateParameters(pImage, bBuf, aISCSIRes[1].cbSeg);
1458	if (RT_FAILURE(rc))
1459	break;
1460
1461	const char *pcszChapAuthMethod;
1462	const char *pcszChapIdxTarget;
1463	const char *pcszChapChallengeStr;
1464
1465	rc = iscsiTextGetKeyValue(bBuf, aISCSIRes[1].cbSeg, "CHAP_A", &pcszChapAuthMethod);
1466	if (RT_FAILURE(rc))
1467	{
1468	rc = VERR_PARSE_ERROR;
1469	break;
1470	}
1471	if (strcmp(pcszChapAuthMethod, "5") != 0)
1472	{
1473	rc = VERR_PARSE_ERROR;
1474	break;
1475	}
1476	rc = iscsiTextGetKeyValue(bBuf, aISCSIRes[1].cbSeg, "CHAP_I", &pcszChapIdxTarget);
1477	if (RT_FAILURE(rc))
1478	{
1479	rc = VERR_PARSE_ERROR;
1480	break;
1481	}
1482	rc = RTStrToUInt8Ex(pcszChapIdxTarget, &pszNext, 0, &bChapIdx);
1483	if ((rc > VINF_SUCCESS) \|\| *pszNext != '\0')
1484	{
1485	rc = VERR_PARSE_ERROR;
1486	break;
1487	}
1488	rc = iscsiTextGetKeyValue(bBuf, aISCSIRes[1].cbSeg, "CHAP_C", &pcszChapChallengeStr);
1489	if (RT_FAILURE(rc))
1490	{
1491	rc = VERR_PARSE_ERROR;
1492	break;
1493	}
1494	cbChallenge = sizeof(pbChallenge);
1495	rc = iscsiStrToBinary(pcszChapChallengeStr, pbChallenge, &cbChallenge);
1496	if (RT_FAILURE(rc))
1497	break;
1498	substate++;
1499	transit = true;
1500	break;
1501	case 0x0002: /* security negotiation, step 2: check authentication success. */
1502	rc = iscsiUpdateParameters(pImage, bBuf, aISCSIRes[1].cbSeg);
1503	if (RT_FAILURE(rc))
1504	break;
1505
1506	if (targetCSG == 0 && targetNSG == 1 && targetTransit)
1507	{
1508	/* Target wants to continue in login operational state, authentication success. */
1509	csg = 1;
1510	nsg = 3;
1511	substate = 0;
1512	break;
1513	}
1514	rc = VERR_PARSE_ERROR;
1515	break;
1516	case 0x0100: /* login operational negotiation, step 0: check results. */
1517	rc = iscsiUpdateParameters(pImage, bBuf, aISCSIRes[1].cbSeg);
1518	if (RT_FAILURE(rc))
1519	break;
1520
1521	if (targetCSG == 1 && targetNSG == 3 && targetTransit)
1522	{
1523	/* Target wants to continue in full feature phase, login finished. */
1524	csg = 3;
1525	nsg = 3;
1526	substate = 0;
1527	break;
1528	}
1529	else if (targetCSG == 1 && targetNSG == 1 && !targetTransit)
1530	{
1531	/* Target wants to negotiate certain parameters and
1532	* stay in login operational negotiation. */
1533	csg = 1;
1534	nsg = 3;
1535	substate = 0;
1536	}
1537	rc = VERR_PARSE_ERROR;
1538	break;
1539	case 0x0300: /* full feature phase. */
1540	default:
1541	AssertMsgFailed(("recv: Undefined login state %d substate %d\n", csg, substate));
1542	rc = VERR_PARSE_ERROR;
1543	break;
1544	}
1545	break;
1546	case ISCSI_LOGIN_STATUS_CLASS_REDIRECTION:
1547	const char *pcszTargetRedir;
1548
1549	/* Target has moved to some other location, as indicated in the TargetAddress key. */
1550	rc = iscsiTextGetKeyValue(bBuf, aISCSIRes[1].cbSeg, "TargetAddress", &pcszTargetRedir);
1551	if (RT_FAILURE(rc))
1552	{
1553	rc = VERR_PARSE_ERROR;
1554	break;
1555	}
1556	if (pImage->pszTargetAddress)
1557	RTMemFree(pImage->pszTargetAddress);
1558	{
1559	size_t cb = strlen(pcszTargetRedir) + 1;
1560	pImage->pszTargetAddress = (char *)RTMemAlloc(cb);
1561	if (!pImage->pszTargetAddress)
1562	{
1563	rc = VERR_NO_MEMORY;
1564	break;
1565	}
1566	memcpy(pImage->pszTargetAddress, pcszTargetRedir, cb);
1567	}
1568	rc = iscsiTransportOpen(pImage);
1569	goto restart;
1570	case ISCSI_LOGIN_STATUS_CLASS_INITIATOR_ERROR:
1571	{
1572	const char *pszDetail = NULL;
1573
1574	switch ((RT_N2H_U32(aResBHS[9]) >> 16) & 0xff)
1575	{
1576	case 0x00:
1577	pszDetail = "Miscelleanous iSCSI intiaitor error";
1578	break;
1579	case 0x01:
1580	pszDetail = "Authentication failure";
1581	break;
1582	case 0x02:
1583	pszDetail = "Authorization failure";
1584	break;
1585	case 0x03:
1586	pszDetail = "Not found";
1587	break;
1588	case 0x04:
1589	pszDetail = "Target removed";
1590	break;
1591	case 0x05:
1592	pszDetail = "Unsupported version";
1593	break;
1594	case 0x06:
1595	pszDetail = "Too many connections";
1596	break;
1597	case 0x07:
1598	pszDetail = "Missing parameter";
1599	break;
1600	case 0x08:
1601	pszDetail = "Can't include in session";
1602	break;
1603	case 0x09:
1604	pszDetail = "Session type not supported";
1605	break;
1606	case 0x0a:
1607	pszDetail = "Session does not exist";
1608	break;
1609	case 0x0b:
1610	pszDetail = "Invalid request type during login";
1611	break;
1612	default:
1613	pszDetail = "Unknown status detail";
1614	}
1615	LogRel(("iSCSI: login to target failed with: %s\n", pszDetail));
1616	iscsiTransportClose(pImage);
1617	rc = VERR_IO_GEN_FAILURE;
1618	goto out;
1619	}
1620	case ISCSI_LOGIN_STATUS_CLASS_TARGET_ERROR:
1621	iscsiTransportClose(pImage);
1622	rc = VINF_EOF;
1623	break;
1624	default:
1625	rc = VERR_PARSE_ERROR;
1626	}
1627
1628	if (csg == 3)
1629	{
1630	/*
1631	* Finished login, continuing with Full Feature Phase.
1632	*/
1633	rc = VINF_SUCCESS;
1634	break;
1635	}
1636	}
1637	else
1638	{
1639	AssertMsgFailed(("%s: ignoring unexpected PDU with first word = %#08x\n", __FUNCTION__, RT_N2H_U32(aResBHS[0])));
1640	}
1641	}
1642	else
1643	break;
1644	} while (true);
1645
1646	out:
1647	if (RT_FAILURE(rc))
1648	{
1649	/*
1650	* Close connection to target.
1651	*/
1652	iscsiTransportClose(pImage);
1653	pImage->state = ISCSISTATE_FREE;
1654	}
1655	else
1656	pImage->state = ISCSISTATE_NORMAL;
1657
1658	RTSemMutexRelease(pImage->Mutex);
1659
1660	LogFlowFunc(("returning %Rrc\n", rc));
1661	LogRel(("iSCSI: login to target %s %s\n", pImage->pszTargetName, RT_SUCCESS(rc) ? "successful" : "failed"));
1662	return rc;
1663	}
1664
1665
1666	/**
1667	* Detach from an iSCSI target.
1668	*
1669	* @returns VBox status.
1670	* @param pImage The iSCSI connection state to be used.
1671	*/
1672	static int iscsiDetach(void *pvUser)
1673	{
1674	int rc;
1675	uint32_t itt;
1676	uint32_t cnISCSIReq = 0;
1677	ISCSIREQ aISCSIReq[4];
1678	uint32_t aReqBHS[12];
1679	PISCSIIMAGE pImage = (PISCSIIMAGE)pvUser;
1680
1681	LogFlowFunc(("entering\n"));
1682
1683	RTSemMutexRequest(pImage->Mutex, RT_INDEFINITE_WAIT);
1684
1685	if (pImage->state != ISCSISTATE_FREE && pImage->state != ISCSISTATE_IN_LOGOUT)
1686	{
1687	pImage->state = ISCSISTATE_IN_LOGOUT;
1688
1689	/*
1690	* Send logout request to target.
1691	*/
1692	itt = iscsiNewITT(pImage);
1693	aReqBHS[0] = RT_H2N_U32(ISCSI_FINAL_BIT \| ISCSIOP_LOGOUT_REQ); /* I=0,F=1,Reason=close session */
1694	aReqBHS[1] = RT_H2N_U32(0); /* TotalAHSLength=0,DataSementLength=0 */
1695	aReqBHS[2] = 0; /* reserved */
1696	aReqBHS[3] = 0; /* reserved */
1697	aReqBHS[4] = itt;
1698	aReqBHS[5] = 0; /* reserved */
1699	aReqBHS[6] = RT_H2N_U32(pImage->CmdSN);
1700	aReqBHS[7] = RT_H2N_U32(pImage->ExpStatSN);
1701	aReqBHS[8] = 0; /* reserved */
1702	aReqBHS[9] = 0; /* reserved */
1703	aReqBHS[10] = 0; /* reserved */
1704	aReqBHS[11] = 0; /* reserved */
1705	pImage->CmdSN++;
1706
1707	aISCSIReq[cnISCSIReq].pcvSeg = aReqBHS;
1708	aISCSIReq[cnISCSIReq].cbSeg = sizeof(aReqBHS);
1709	cnISCSIReq++;
1710
1711	rc = iscsiSendPDU(pImage, aISCSIReq, cnISCSIReq, ISCSIPDU_NO_REATTACH);
1712	if (RT_SUCCESS(rc))
1713	{
1714	/*
1715	* Read logout response from target.
1716	*/
1717	ISCSIRES aISCSIRes;
1718	uint32_t aResBHS[12];
1719
1720	aISCSIRes.pvSeg = aResBHS;
1721	aISCSIRes.cbSeg = sizeof(aResBHS);
1722	rc = iscsiRecvPDU(pImage, itt, &aISCSIRes, 1);
1723	if (RT_SUCCESS(rc))
1724	{
1725	if (RT_N2H_U32(aResBHS[0]) != (ISCSI_FINAL_BIT \| ISCSIOP_LOGOUT_RES))
1726	AssertMsgFailed(("iSCSI Logout response invalid\n"));
1727	}
1728	else
1729	AssertMsgFailed(("iSCSI Logout response error, rc=%Rrc\n", rc));
1730	}
1731	else
1732	AssertMsgFailed(("Could not send iSCSI Logout request, rc=%Rrc\n", rc));
1733	}
1734
1735	if (pImage->state != ISCSISTATE_FREE)
1736	{
1737	/*
1738	* Close connection to target.
1739	*/
1740	rc = iscsiTransportClose(pImage);
1741	if (RT_FAILURE(rc))
1742	AssertMsgFailed(("Could not close connection to target, rc=%Rrc\n", rc));
1743	}
1744
1745	pImage->state = ISCSISTATE_FREE;
1746
1747	RTSemMutexRelease(pImage->Mutex);
1748
1749	LogFlowFunc(("leaving\n"));
1750	LogRel(("iSCSI: logout to target %s\n", pImage->pszTargetName));
1751	return VINF_SUCCESS;
1752	}
1753
1754
1755	/**
1756	* Perform a command on an iSCSI target. Target must be already in
1757	* Full Feature Phase.
1758	*
1759	* @returns VBOX status.
1760	* @param pImage The iSCSI connection state to be used.
1761	* @param pRequest Command descriptor. Contains all information about
1762	* the command, its transfer directions and pointers
1763	* to the buffer(s) used for transferring data and
1764	* status information.
1765	*/
1766	static int iscsiCommand(PISCSIIMAGE pImage, PSCSIREQ pRequest)
1767	{
1768	int rc;
1769	uint32_t itt;
1770	uint32_t cbData;
1771	uint32_t cnISCSIReq = 0;
1772	ISCSIREQ aISCSIReq[4];
1773	uint32_t aReqBHS[12];
1774
1775	uint32_t *pDst = NULL;
1776	size_t cbBufLength;
1777	uint32_t aStatus[256]; /*< Plenty of buffer for status information. /
1778	uint32_t ExpDataSN = 0;
1779	bool final = false;
1780
1781
1782	LogFlowFunc(("entering, CmdSN=%d\n", pImage->CmdSN));
1783
1784	Assert(pRequest->enmXfer != SCSIXFER_TO_FROM_TARGET); /*< @todo not yet supported, would require AHS. /
1785	Assert(pRequest->cbI2TData <= 0xffffff); /* larger transfers would require R2T support. */
1786	Assert(pRequest->cbCDB <= 16); /* would cause buffer overrun below. */
1787
1788	/* If not in normal state, then the transport connection was dropped. Try
1789	* to reestablish by logging in, the target might be responsive again. */
1790	if (pImage->state == ISCSISTATE_FREE)
1791	rc = iscsiAttach(pImage);
1792
1793	/* If still not in normal state, then the underlying transport connection
1794	* cannot be established. Get out before bad things happen (and make
1795	* sure the caller suspends the VM again). */
1796	if (pImage->state != ISCSISTATE_NORMAL)
1797	{
1798	rc = VERR_NET_CONNECTION_REFUSED;
1799	goto out;
1800	}
1801
1802	/*
1803	* Send SCSI command to target with all I2T data included.
1804	*/
1805	cbData = 0;
1806	if (pRequest->enmXfer == SCSIXFER_FROM_TARGET)
1807	cbData = (uint32_t)pRequest->cbT2IData;
1808	else
1809	cbData = (uint32_t)pRequest->cbI2TData;
1810
1811	RTSemMutexRequest(pImage->Mutex, RT_INDEFINITE_WAIT);
1812
1813	itt = iscsiNewITT(pImage);
1814	memset(aReqBHS, 0, sizeof(aReqBHS));
1815	aReqBHS[0] = RT_H2N_U32( ISCSI_FINAL_BIT \| ISCSI_TASK_ATTR_SIMPLE \| ISCSIOP_SCSI_CMD
1816	\| (pRequest->enmXfer << 21)); /* I=0,F=1,Attr=Simple */
1817	aReqBHS[1] = RT_H2N_U32(0x00000000 \| ((uint32_t)pRequest->cbI2TData & 0xffffff)); /* TotalAHSLength=0 */
1818	aReqBHS[2] = RT_H2N_U32(pImage->LUN >> 32);
1819	aReqBHS[3] = RT_H2N_U32(pImage->LUN & 0xffffffff);
1820	aReqBHS[4] = itt;
1821	aReqBHS[5] = RT_H2N_U32(cbData);
1822	aReqBHS[6] = RT_H2N_U32(pImage->CmdSN);
1823	aReqBHS[7] = RT_H2N_U32(pImage->ExpStatSN);
1824	memcpy(aReqBHS + 8, pRequest->pvCDB, pRequest->cbCDB);
1825	pImage->CmdSN++;
1826
1827	aISCSIReq[cnISCSIReq].pcvSeg = aReqBHS;
1828	aISCSIReq[cnISCSIReq].cbSeg = sizeof(aReqBHS);
1829	cnISCSIReq++;
1830
1831	if ( pRequest->enmXfer == SCSIXFER_TO_TARGET
1832	\|\| pRequest->enmXfer == SCSIXFER_TO_FROM_TARGET)
1833	{
1834	Assert(pRequest->cI2TSegs == 1);
1835	aISCSIReq[cnISCSIReq].pcvSeg = pRequest->paI2TSegs[0].pvSeg;
1836	aISCSIReq[cnISCSIReq].cbSeg = pRequest->paI2TSegs[0].cbSeg; /* Padding done by transport. */
1837	cnISCSIReq++;
1838	}
1839
1840	rc = iscsiSendPDU(pImage, aISCSIReq, cnISCSIReq, ISCSIPDU_DEFAULT);
1841	if (RT_FAILURE(rc))
1842	goto out_release;
1843
1844	/* Place SCSI request in queue. */
1845	pImage->paCurrReq = aISCSIReq;
1846	pImage->cnCurrReq = cnISCSIReq;
1847
1848	/*
1849	* Read SCSI response/data in PDUs from target.
1850	*/
1851	if ( pRequest->enmXfer == SCSIXFER_FROM_TARGET
1852	\|\| pRequest->enmXfer == SCSIXFER_TO_FROM_TARGET)
1853	{
1854	Assert(pRequest->cT2ISegs == 1);
1855	pDst = (uint32_t *)pRequest->paT2ISegs[0].pvSeg;
1856	cbBufLength = pRequest->paT2ISegs[0].cbSeg;
1857	}
1858	else
1859	cbBufLength = 0;
1860
1861	do {
1862	uint32_t cnISCSIRes = 0;
1863	ISCSIRES aISCSIRes[4];
1864	uint32_t aResBHS[12];
1865
1866	aISCSIRes[cnISCSIRes].pvSeg = aResBHS;
1867	aISCSIRes[cnISCSIRes].cbSeg = sizeof(aResBHS);
1868	cnISCSIRes++;
1869	if (cbBufLength != 0 &&
1870	( pRequest->enmXfer == SCSIXFER_FROM_TARGET
1871	\|\| pRequest->enmXfer == SCSIXFER_TO_FROM_TARGET))
1872	{
1873	aISCSIRes[cnISCSIRes].pvSeg = pDst;
1874	aISCSIRes[cnISCSIRes].cbSeg = cbBufLength;
1875	cnISCSIRes++;
1876	}
1877	/* Always reserve space for the status - it's impossible to tell
1878	* beforehand whether this will be the final PDU or not. */
1879	aISCSIRes[cnISCSIRes].pvSeg = aStatus;
1880	aISCSIRes[cnISCSIRes].cbSeg = sizeof(aStatus);
1881	cnISCSIRes++;
1882
1883	rc = iscsiRecvPDU(pImage, itt, aISCSIRes, cnISCSIRes);
1884	if (RT_FAILURE(rc))
1885	break;
1886
1887	final = !!(RT_N2H_U32(aResBHS[0]) & ISCSI_FINAL_BIT);
1888	ISCSIOPCODE cmd = (ISCSIOPCODE)(RT_N2H_U32(aResBHS[0]) & ISCSIOP_MASK);
1889	if (cmd == ISCSIOP_SCSI_RES)
1890	{
1891	/* This is the final PDU which delivers the status (and may be omitted if
1892	* the last Data-In PDU included successful completion status). Note
1893	* that ExpStatSN has been bumped already in iscsiRecvPDU. */
1894	if (!final \|\| ((RT_N2H_U32(aResBHS[0]) & 0x0000ff00) != 0) \|\| (RT_N2H_U32(aResBHS[6]) != pImage->ExpStatSN - 1))
1895	{
1896	/* SCSI Response in the wrong place or with a (target) failure. */
1897	rc = VERR_PARSE_ERROR;
1898	break;
1899	}
1900	/* The following is a bit tricky, as in error situations we may
1901	* get the status only instead of the result data plus optional
1902	* status. Thus the status may have ended up partially in the
1903	* data area. */
1904	pRequest->status = RT_N2H_U32(aResBHS[0]) & 0x000000ff;
1905	cbData = RT_N2H_U32(aResBHS[1]) & 0x00ffffff;
1906	if (cbData >= 2)
1907	{
1908	uint32_t cbStat = RT_N2H_U32(((uint32_t *)aISCSIRes[1].pvSeg)[0]) >> 16;
1909	if (cbStat + 2 > cbData)
1910	{
1911	rc = VERR_BUFFER_OVERFLOW;
1912	break;
1913	}
1914	/* Truncate sense data if it doesn't fit into the buffer. */
1915	pRequest->cbSense = RT_MIN(cbStat, pRequest->cbSense);
1916	memcpy(pRequest->pvSense,
1917	((const char *)aISCSIRes[1].pvSeg) + 2,
1918	RT_MIN(aISCSIRes[1].cbSeg - 2, pRequest->cbSense));
1919	if ( cnISCSIRes > 2 && aISCSIRes[2].cbSeg
1920	&& (ssize_t)pRequest->cbSense - aISCSIRes[1].cbSeg + 2 > 0)
1921	{
1922	memcpy((char *)pRequest->pvSense + aISCSIRes[1].cbSeg - 2,
1923	aISCSIRes[2].pvSeg,
1924	pRequest->cbSense - aISCSIRes[1].cbSeg + 2);
1925	}
1926	}
1927	else if (cbData == 1)
1928	{
1929	rc = VERR_PARSE_ERROR;
1930	break;
1931	}
1932	else
1933	pRequest->cbSense = 0;
1934	break;
1935	}
1936	else if (cmd == ISCSIOP_SCSI_DATA_IN)
1937	{
1938	/* A Data-In PDU carries some data that needs to be added to the received
1939	* data in response to the command. There may be both partial and complete
1940	* Data-In PDUs, so collect data until the status is included or the status
1941	* is sent in a separate SCSI Result frame (see above). */
1942	if (final && aISCSIRes[2].cbSeg != 0)
1943	{
1944	/* The received PDU is partially stored in the buffer for status.
1945	* Must not happen under normal circumstances and is a target error. */
1946	rc = VERR_BUFFER_OVERFLOW;
1947	break;
1948	}
1949	uint32_t len = RT_N2H_U32(aResBHS[1]) & 0x00ffffff;
1950	pDst = (uint32_t )((char )pDst + len);
1951	cbBufLength -= len;
1952	ExpDataSN++;
1953	if (final && (RT_N2H_U32(aResBHS[0]) & ISCSI_STATUS_BIT) != 0)
1954	{
1955	pRequest->status = RT_N2H_U32(aResBHS[0]) & 0x000000ff;
1956	pRequest->cbSense = 0;
1957	break;
1958	}
1959	}
1960	else
1961	{
1962	rc = VERR_PARSE_ERROR;
1963	break;
1964	}
1965	} while (true);
1966
1967	/* Remove SCSI request from queue. */
1968	pImage->paCurrReq = NULL;
1969	pImage->cnCurrReq = 0;
1970
1971	out_release:
1972	if (rc == VERR_TIMEOUT)
1973	{
1974	/* Drop connection in case the target plays dead. Much better than
1975	* delaying the next requests until the timed out command actually
1976	* finishes. Also keep in mind that command shouldn't take longer than
1977	* about 30-40 seconds, or the guest will lose its patience. */
1978	iscsiTransportClose(pImage);
1979	pImage->state = ISCSISTATE_FREE;
1980	rc = VERR_BROKEN_PIPE;
1981	}
1982	RTSemMutexRelease(pImage->Mutex);
1983
1984	out:
1985	LogFlowFunc(("returns %Rrc\n", rc));
1986	return rc;
1987	}
1988
1989
1990	/**
1991	* Generate a new Initiator Task Tag.
1992	*
1993	* @returns Initiator Task Tag.
1994	* @param pImage The iSCSI connection state to be used.
1995	*/
1996	static uint32_t iscsiNewITT(PISCSIIMAGE pImage)
1997	{
1998	uint32_t next_itt;
1999
2000	next_itt = pImage->ITT++;
2001	if (pImage->ITT == ISCSI_TASK_TAG_RSVD)
2002	pImage->ITT = 0;
2003	return RT_H2N_U32(next_itt);
2004	}
2005
2006
2007	/**
2008	* Send an iSCSI request. The request can consist of several segments, which
2009	* are padded to 4 byte boundaries and concatenated.
2010	*
2011	* @returns VBOX status
2012	* @param pImage The iSCSI connection state to be used.
2013	* @param paReq Pointer to array of iSCSI request sections.
2014	* @param cnReq Number of valid iSCSI request sections in the array.
2015	* @param uFlags Flags controlling the exact send semantics.
2016	*/
2017	static int iscsiSendPDU(PISCSIIMAGE pImage, PISCSIREQ paReq, uint32_t cnReq,
2018	uint32_t uFlags)
2019	{
2020	int rc = VINF_SUCCESS;
2021	/** @todo return VERR_VD_ISCSI_INVALID_STATE in the appropriate situations,
2022	* needs cleaning up of timeout/disconnect handling a bit, as otherwise
2023	* too many incorrect errors are signalled. */
2024	Assert(cnReq >= 1);
2025	Assert(paReq[0].cbSeg >= ISCSI_BHS_SIZE);
2026
2027	for (uint32_t i = 0; i < pImage->cISCSIRetries; i++)
2028	{
2029	rc = iscsiTransportWrite(pImage, paReq, cnReq);
2030	if (RT_SUCCESS(rc))
2031	break;
2032	if ( (uFlags & ISCSIPDU_NO_REATTACH)
2033	\|\| (rc != VERR_BROKEN_PIPE && rc != VERR_NET_CONNECTION_REFUSED))
2034	break;
2035	/* No point in reestablishing the connection for a logout */
2036	if (pImage->state == ISCSISTATE_IN_LOGOUT)
2037	break;
2038	RTThreadSleep(500);
2039	if (pImage->state != ISCSISTATE_IN_LOGIN)
2040	{
2041	/* Attempt to re-login when a connection fails, but only when not
2042	* currently logging in. */
2043	rc = iscsiAttach(pImage);
2044	if (RT_FAILURE(rc))
2045	break;
2046	}
2047	}
2048	return rc;
2049	}
2050
2051
2052	/**
2053	* Wait for an iSCSI response with a matching Initiator Target Tag. The response is
2054	* split into several segments, as requested by the caller-provided buffer specification.
2055	* Remember that the response can be split into several PDUs by the sender, so make
2056	* sure that all parts are collected and processed appropriately by the caller.
2057	*
2058	* @returns VBOX status
2059	* @param pImage The iSCSI connection state to be used.
2060	* @param paRes Pointer to array of iSCSI response sections.
2061	* @param cnRes Number of valid iSCSI response sections in the array.
2062	*/
2063	static int iscsiRecvPDU(PISCSIIMAGE pImage, uint32_t itt, PISCSIRES paRes, uint32_t cnRes)
2064	{
2065	int rc = VINF_SUCCESS;
2066	ISCSIRES aResBuf;
2067
2068	for (uint32_t i = 0; i < pImage->cISCSIRetries; i++)
2069	{
2070	aResBuf.pvSeg = pImage->pvRecvPDUBuf;
2071	aResBuf.cbSeg = pImage->cbRecvPDUBuf;
2072	rc = iscsiTransportRead(pImage, &aResBuf, 1);
2073	if (RT_FAILURE(rc))
2074	{
2075	if (rc == VERR_BROKEN_PIPE \|\| rc == VERR_NET_CONNECTION_REFUSED)
2076	{
2077	/* No point in reestablishing the connection for a logout */
2078	if (pImage->state == ISCSISTATE_IN_LOGOUT)
2079	break;
2080	/* Connection broken while waiting for a response - wait a while and
2081	* try to restart by re-sending the original request (if any).
2082	* This also handles the connection reestablishment (login etc.). */
2083	RTThreadSleep(500);
2084	if (pImage->state != ISCSISTATE_IN_LOGIN)
2085	{
2086	/* Attempt to re-login when a connection fails, but only when not
2087	* currently logging in. */
2088	rc = iscsiAttach(pImage);
2089	if (RT_FAILURE(rc))
2090	break;
2091	}
2092	if (pImage->paCurrReq != NULL)
2093	{
2094	rc = iscsiSendPDU(pImage, pImage->paCurrReq, pImage->cnCurrReq, ISCSIPDU_DEFAULT);
2095	if (RT_FAILURE(rc))
2096	break;
2097	}
2098	}
2099	else
2100	{
2101	/* Signal other errors (VERR_BUFFER_OVERFLOW etc.) to the caller. */
2102	break;
2103	}
2104	}
2105	else
2106	{
2107	ISCSIOPCODE cmd;
2108	const uint32_t pcvResSeg = (const uint32_t )aResBuf.pvSeg;
2109
2110	/* Check whether the received PDU is valid, and update the internal state of
2111	* the iSCSI connection/session. */
2112	rc = iscsiValidatePDU(&aResBuf, 1);
2113	if (RT_FAILURE(rc))
2114	continue;
2115	cmd = (ISCSIOPCODE)(RT_N2H_U32(pcvResSeg[0]) & ISCSIOP_MASK);
2116	switch (cmd)
2117	{
2118	case ISCSIOP_SCSI_RES:
2119	case ISCSIOP_SCSI_TASKMGMT_RES:
2120	case ISCSIOP_SCSI_DATA_IN:
2121	case ISCSIOP_R2T:
2122	case ISCSIOP_ASYN_MSG:
2123	case ISCSIOP_TEXT_RES:
2124	case ISCSIOP_LOGIN_RES:
2125	case ISCSIOP_LOGOUT_RES:
2126	case ISCSIOP_REJECT:
2127	case ISCSIOP_NOP_IN:
2128	if (serial_number_less(pImage->MaxCmdSN, RT_N2H_U32(pcvResSeg[8])))
2129	pImage->MaxCmdSN = RT_N2H_U32(pcvResSeg[8]);
2130	if (serial_number_less(pImage->ExpCmdSN, RT_N2H_U32(pcvResSeg[7])))
2131	pImage->ExpCmdSN = RT_N2H_U32(pcvResSeg[7]);
2132	break;
2133	default:
2134	rc = VERR_PARSE_ERROR;
2135	}
2136	if (RT_FAILURE(rc))
2137	continue;
2138	if ( !pImage->FirstRecvPDU
2139	&& (cmd != ISCSIOP_SCSI_DATA_IN \|\| (RT_N2H_U32(pcvResSeg[0]) & ISCSI_STATUS_BIT))
2140	&& ( cmd != ISCSIOP_LOGIN_RES
2141	\|\| (ISCSILOGINSTATUSCLASS)((RT_N2H_U32(pcvResSeg[9]) >> 24) == ISCSI_LOGIN_STATUS_CLASS_SUCCESS)))
2142	{
2143	if (pImage->ExpStatSN == RT_N2H_U32(pcvResSeg[6]))
2144	{
2145	/* StatSN counter is not advanced on R2T and on a target SN update NOP-In. */
2146	if ( (cmd != ISCSIOP_R2T)
2147	&& ((cmd != ISCSIOP_NOP_IN) \|\| (RT_N2H_U32(pcvResSeg[4]) != ISCSI_TASK_TAG_RSVD)))
2148	pImage->ExpStatSN++;
2149	}
2150	else
2151	{
2152	rc = VERR_PARSE_ERROR;
2153	continue;
2154	}
2155	}
2156	/* Finally check whether the received PDU matches what the caller wants. */
2157	if ( itt == pcvResSeg[4]
2158	&& itt != ISCSI_TASK_TAG_RSVD)
2159	{
2160	/* Copy received PDU (one segment) to caller-provided buffers. */
2161	uint32_t j;
2162	size_t cbSeg;
2163	const uint8_t *pSrc;
2164
2165	pSrc = (const uint8_t *)aResBuf.pvSeg;
2166	cbSeg = aResBuf.cbSeg;
2167	for (j = 0; j < cnRes; j++)
2168	{
2169	if (cbSeg > paRes[j].cbSeg)
2170	{
2171	memcpy(paRes[j].pvSeg, pSrc, paRes[j].cbSeg);
2172	pSrc += paRes[j].cbSeg;
2173	cbSeg -= paRes[j].cbSeg;
2174	}
2175	else
2176	{
2177	memcpy(paRes[j].pvSeg, pSrc, cbSeg);
2178	paRes[j].cbSeg = cbSeg;
2179	cbSeg = 0;
2180	break;
2181	}
2182	}
2183	if (cbSeg != 0)
2184	{
2185	rc = VERR_BUFFER_OVERFLOW;
2186	break;
2187	}
2188	for (j++; j < cnRes; j++)
2189	paRes[j].cbSeg = 0;
2190	break;
2191	}
2192	else if ( cmd == ISCSIOP_NOP_IN
2193	&& RT_N2H_U32(pcvResSeg[5]) != ISCSI_TASK_TAG_RSVD)
2194	{
2195	uint32_t cnISCSIReq;
2196	ISCSIREQ aISCSIReq[4];
2197	uint32_t aReqBHS[12];
2198
2199	aReqBHS[0] = RT_H2N_U32(ISCSI_IMMEDIATE_DELIVERY_BIT \| ISCSI_FINAL_BIT \| ISCSIOP_NOP_OUT);
2200	aReqBHS[1] = RT_H2N_U32(0); /* TotalAHSLength=0,DataSementLength=0 */
2201	aReqBHS[2] = pcvResSeg[2]; /* copy LUN from NOP-In */
2202	aReqBHS[3] = pcvResSeg[3]; /* copy LUN from NOP-In */
2203	aReqBHS[4] = RT_H2N_U32(ISCSI_TASK_TAG_RSVD); /* ITT, reply */
2204	aReqBHS[5] = pcvResSeg[5]; /* copy TTT from NOP-In */
2205	aReqBHS[6] = RT_H2N_U32(pImage->CmdSN);
2206	aReqBHS[7] = RT_H2N_U32(pImage->ExpStatSN);
2207	aReqBHS[8] = 0; /* reserved */
2208	aReqBHS[9] = 0; /* reserved */
2209	aReqBHS[10] = 0; /* reserved */
2210	aReqBHS[11] = 0; /* reserved */
2211
2212	cnISCSIReq = 0;
2213	aISCSIReq[cnISCSIReq].pcvSeg = aReqBHS;
2214	aISCSIReq[cnISCSIReq].cbSeg = sizeof(aReqBHS);
2215	cnISCSIReq++;
2216
2217	iscsiSendPDU(pImage, aISCSIReq, cnISCSIReq, ISCSIPDU_NO_REATTACH);
2218	/* Break if the caller wanted to process the NOP-in only. */
2219	if (itt == ISCSI_TASK_TAG_RSVD)
2220	break;
2221	}
2222	}
2223	}
2224
2225	LogFlowFunc(("returns rc=%Rrc\n"));
2226	return rc;
2227	}
2228
2229
2230	/**
2231	* Reset the PDU buffer
2232	*
2233	* @param pImage The iSCSI connection state to be used.
2234	*/
2235	static void iscsiRecvPDUReset(PISCSIIMAGE pImage)
2236	{
2237	pImage->cbRecvPDUResidual = ISCSI_BHS_SIZE;
2238	pImage->fRecvPDUBHS = true;
2239	pImage->pbRecvPDUBufCur = (uint8_t *)pImage->pvRecvPDUBuf;
2240	}
2241
2242	static void iscsiPDUTxAdd(PISCSIIMAGE pImage, PISCSIPDUTX pIScsiPDUTx, bool fFront)
2243	{
2244	if (!fFront)
2245	{
2246	/* Insert PDU at the tail of the list. */
2247	if (!pImage->pIScsiPDUTxHead)
2248	pImage->pIScsiPDUTxHead = pIScsiPDUTx;
2249	else
2250	pImage->pIScsiPDUTxTail->pNext = pIScsiPDUTx;
2251	pImage->pIScsiPDUTxTail = pIScsiPDUTx;
2252	}
2253	else
2254	{
2255	/* Insert PDU at the beginning of the list. */
2256	pIScsiPDUTx->pNext = pImage->pIScsiPDUTxHead;
2257	pImage->pIScsiPDUTxHead = pIScsiPDUTx;
2258	if (!pImage->pIScsiPDUTxTail)
2259	pImage->pIScsiPDUTxTail = pIScsiPDUTx;
2260	}
2261	}
2262
2263	/**
2264	* Receives a PDU in a non blocking way.
2265	*
2266	* @returns VBOX status code.
2267	* @param pImage The iSCSI connection state to be used.
2268	*/
2269	static int iscsiRecvPDUAsync(PISCSIIMAGE pImage)
2270	{
2271	size_t cbActuallyRead = 0;
2272	int rc = VINF_SUCCESS;
2273
2274	LogFlowFunc(("pImage=%#p\n", pImage));
2275
2276	/* Check if we are in the middle of a PDU receive. */
2277	if (pImage->cbRecvPDUResidual == 0)
2278	{
2279	/*
2280	* We are receiving a new PDU, don't read more than the BHS initially
2281	* until we know the real size of the PDU.
2282	*/
2283	iscsiRecvPDUReset(pImage);
2284	LogFlow(("Receiving new PDU\n"));
2285	}
2286
2287	rc = pImage->pIfNet->pfnReadNB(pImage->Socket, pImage->pbRecvPDUBufCur,
2288	pImage->cbRecvPDUResidual, &cbActuallyRead);
2289	if (RT_SUCCESS(rc) && cbActuallyRead == 0)
2290	rc = VERR_BROKEN_PIPE;
2291
2292	if (RT_SUCCESS(rc))
2293	{
2294	LogFlow(("Received %zu bytes\n", cbActuallyRead));
2295	pImage->cbRecvPDUResidual -= cbActuallyRead;
2296	pImage->pbRecvPDUBufCur += cbActuallyRead;
2297
2298	/* Check if we received everything we wanted. */
2299	if ( !pImage->cbRecvPDUResidual
2300	&& pImage->fRecvPDUBHS)
2301	{
2302	size_t cbAHSLength, cbDataLength;
2303
2304	/* If we were reading the BHS first get the actual PDU size now. */
2305	uint32_t word1 = RT_N2H_U32(((uint32_t *)(pImage->pvRecvPDUBuf))[1]);
2306	cbAHSLength = (word1 & 0xff000000) >> 24;
2307	cbAHSLength = ((cbAHSLength - 1) \| 3) + 1; /* Add padding. */
2308	cbDataLength = word1 & 0x00ffffff;
2309	cbDataLength = ((cbDataLength - 1) \| 3) + 1; /* Add padding. */
2310	pImage->cbRecvPDUResidual = cbAHSLength + cbDataLength;
2311	pImage->fRecvPDUBHS = false; /* Start receiving the rest of the PDU. */
2312	}
2313
2314	if (!pImage->cbRecvPDUResidual)
2315	{
2316	/* We received the complete PDU with or without any payload now. */
2317	LogFlow(("Received complete PDU\n"));
2318	ISCSIRES aResBuf;
2319	aResBuf.pvSeg = pImage->pvRecvPDUBuf;
2320	aResBuf.cbSeg = pImage->cbRecvPDUBuf;
2321	rc = iscsiRecvPDUProcess(pImage, &aResBuf, 1);
2322	}
2323	}
2324	else
2325	LogFlowFunc(("Reading from the socket returned with rc=%Rrc\n", rc));
2326
2327	return rc;
2328	}
2329
2330	static int iscsiSendPDUAsync(PISCSIIMAGE pImage)
2331	{
2332	size_t cbSent = 0;
2333	int rc = VINF_SUCCESS;
2334
2335	LogFlowFunc(("pImage=%#p\n", pImage));
2336
2337	do
2338	{
2339	/*
2340	* If there is no PDU active, get the first one from the list.
2341	* Check that we are allowed to transfer the PDU by comparing the
2342	* command sequence number and the maximum sequence number allowed by the target.
2343	*/
2344	if (!pImage->pIScsiPDUTxCur)
2345	{
2346	if ( !pImage->pIScsiPDUTxHead
2347	\|\| serial_number_greater(pImage->pIScsiPDUTxHead->CmdSN, pImage->MaxCmdSN))
2348	break;
2349
2350	pImage->pIScsiPDUTxCur = pImage->pIScsiPDUTxHead;
2351	pImage->pIScsiPDUTxHead = pImage->pIScsiPDUTxCur->pNext;
2352	if (!pImage->pIScsiPDUTxHead)
2353	pImage->pIScsiPDUTxTail = NULL;
2354	}
2355
2356	/* Send as much as we can. */
2357	rc = pImage->pIfNet->pfnSgWriteNB(pImage->Socket, &pImage->pIScsiPDUTxCur->SgBuf, &cbSent);
2358	LogFlow(("SgWriteNB returned rc=%Rrc cbSent=%zu\n", rc, cbSent));
2359	if (RT_SUCCESS(rc))
2360	{
2361	LogFlow(("Sent %zu bytes for PDU %#p\n", cbSent, pImage->pIScsiPDUTxCur));
2362	pImage->pIScsiPDUTxCur->cbSgLeft -= cbSent;
2363	RTSgBufAdvance(&pImage->pIScsiPDUTxCur->SgBuf, cbSent);
2364	if (!pImage->pIScsiPDUTxCur->cbSgLeft)
2365	{
2366	/* PDU completed, free it and place the command on the waiting for response list. */
2367	if (pImage->pIScsiPDUTxCur->pIScsiCmd)
2368	{
2369	LogFlow(("Sent complete PDU, placing on waiting list\n"));
2370	iscsiCmdInsert(pImage, pImage->pIScsiPDUTxCur->pIScsiCmd);
2371	}
2372	RTMemFree(pImage->pIScsiPDUTxCur);
2373	pImage->pIScsiPDUTxCur = NULL;
2374	}
2375	}
2376	} while ( RT_SUCCESS(rc)
2377	&& !pImage->pIScsiPDUTxCur);
2378
2379	if (rc == VERR_TRY_AGAIN)
2380	rc = VINF_SUCCESS;
2381
2382	/* Add the write poll flag if we still have something to send, clear it otherwise. */
2383	if (pImage->pIScsiPDUTxCur)
2384	pImage->fPollEvents \|= VD_INTERFACETCPNET_EVT_WRITE;
2385	else
2386	pImage->fPollEvents &= ~VD_INTERFACETCPNET_EVT_WRITE;
2387
2388	LogFlowFunc(("rc=%Rrc pIScsiPDUTxCur=%#p\n", rc, pImage->pIScsiPDUTxCur));
2389	return rc;
2390	}
2391
2392	/**
2393	* Process a received PDU.
2394	*
2395	* @return VBOX status code.
2396	* @param pImage The iSCSI connection state to be used.
2397	* @param paRes Pointer to the array of iSCSI response sections.
2398	* @param cnRes Number of valid iSCSI response sections in the array.
2399	*/
2400	static int iscsiRecvPDUProcess(PISCSIIMAGE pImage, PISCSIRES paRes, uint32_t cnRes)
2401	{
2402	int rc = VINF_SUCCESS;
2403
2404	LogFlowFunc(("pImage=%#p paRes=%#p cnRes=%u\n", pImage, paRes, cnRes));
2405
2406	/* Validate the PDU first. */
2407	rc = iscsiValidatePDU(paRes, cnRes);
2408	if (RT_SUCCESS(rc))
2409	{
2410	ISCSIOPCODE cmd;
2411	const uint32_t pcvResSeg = (const uint32_t )paRes[0].pvSeg;
2412
2413	Assert(paRes[0].cbSeg > 9 * sizeof(uint32_t));
2414
2415	do
2416	{
2417	cmd = (ISCSIOPCODE)(RT_N2H_U32(pcvResSeg[0]) & ISCSIOP_MASK);
2418	switch (cmd)
2419	{
2420	case ISCSIOP_SCSI_RES:
2421	case ISCSIOP_SCSI_TASKMGMT_RES:
2422	case ISCSIOP_SCSI_DATA_IN:
2423	case ISCSIOP_R2T:
2424	case ISCSIOP_ASYN_MSG:
2425	case ISCSIOP_TEXT_RES:
2426	case ISCSIOP_LOGIN_RES:
2427	case ISCSIOP_LOGOUT_RES:
2428	case ISCSIOP_REJECT:
2429	case ISCSIOP_NOP_IN:
2430	if (serial_number_less(pImage->MaxCmdSN, RT_N2H_U32(pcvResSeg[8])))
2431	pImage->MaxCmdSN = RT_N2H_U32(pcvResSeg[8]);
2432	if (serial_number_less(pImage->ExpCmdSN, RT_N2H_U32(pcvResSeg[7])))
2433	pImage->ExpCmdSN = RT_N2H_U32(pcvResSeg[7]);
2434	break;
2435	default:
2436	rc = VERR_PARSE_ERROR;
2437	}
2438
2439	if (RT_FAILURE(rc))
2440	break;
2441
2442	if ( !pImage->FirstRecvPDU
2443	&& (cmd != ISCSIOP_SCSI_DATA_IN \|\| (RT_N2H_U32(pcvResSeg[0]) & ISCSI_STATUS_BIT)))
2444	{
2445	if (pImage->ExpStatSN == RT_N2H_U32(pcvResSeg[6]))
2446	{
2447	/* StatSN counter is not advanced on R2T and on a target SN update NOP-In. */
2448	if ( (cmd != ISCSIOP_R2T)
2449	&& ((cmd != ISCSIOP_NOP_IN) \|\| (RT_N2H_U32(pcvResSeg[4]) != ISCSI_TASK_TAG_RSVD)))
2450	pImage->ExpStatSN++;
2451	}
2452	else
2453	{
2454	rc = VERR_PARSE_ERROR;
2455	break;
2456	}
2457	}
2458
2459	if (pcvResSeg[4] != ISCSI_TASK_TAG_RSVD)
2460	{
2461	/*
2462	* This is a response from the target for a request from the initiator.
2463	* Get the request and update its state.
2464	*/
2465	rc = iscsiRecvPDUUpdateRequest(pImage, paRes, cnRes);
2466	/* Try to send more PDUs now that we updated the MaxCmdSN field */
2467	if ( RT_SUCCESS(rc)
2468	&& !pImage->pIScsiPDUTxCur)
2469	rc = iscsiSendPDUAsync(pImage);
2470	}
2471	else
2472	{
2473	/* This is a target initiated request (we handle only NOP-In request at the moment). */
2474	if ( cmd == ISCSIOP_NOP_IN
2475	&& RT_N2H_U32(pcvResSeg[5]) != ISCSI_TASK_TAG_RSVD)
2476	{
2477	PISCSIPDUTX pIScsiPDUTx;
2478	uint32_t cnISCSIReq;
2479	uint32_t *paReqBHS;
2480
2481	LogFlowFunc(("Sending NOP-Out\n"));
2482
2483	/* Allocate a new PDU initialize it and put onto the waiting list. */
2484	pIScsiPDUTx = (PISCSIPDUTX)RTMemAllocZ(sizeof(ISCSIPDUTX));
2485	if (!pIScsiPDUTx)
2486	{
2487	rc = VERR_NO_MEMORY;
2488	break;
2489	}
2490	paReqBHS = &pIScsiPDUTx->aBHS[0];
2491	paReqBHS[0] = RT_H2N_U32(ISCSI_IMMEDIATE_DELIVERY_BIT \| ISCSI_FINAL_BIT \| ISCSIOP_NOP_OUT);
2492	paReqBHS[1] = RT_H2N_U32(0); /* TotalAHSLength=0,DataSementLength=0 */
2493	paReqBHS[2] = pcvResSeg[2]; /* copy LUN from NOP-In */
2494	paReqBHS[3] = pcvResSeg[3]; /* copy LUN from NOP-In */
2495	paReqBHS[4] = RT_H2N_U32(ISCSI_TASK_TAG_RSVD); /* ITT, reply */
2496	paReqBHS[5] = pcvResSeg[5]; /* copy TTT from NOP-In */
2497	paReqBHS[6] = RT_H2N_U32(pImage->CmdSN);
2498	paReqBHS[7] = RT_H2N_U32(pImage->ExpStatSN);
2499	paReqBHS[8] = 0; /* reserved */
2500	paReqBHS[9] = 0; /* reserved */
2501	paReqBHS[10] = 0; /* reserved */
2502	paReqBHS[11] = 0; /* reserved */
2503
2504	cnISCSIReq = 0;
2505	pIScsiPDUTx->aISCSIReq[cnISCSIReq].pvSeg = paReqBHS;
2506	pIScsiPDUTx->aISCSIReq[cnISCSIReq].cbSeg = sizeof(pIScsiPDUTx->aBHS);
2507	cnISCSIReq++;
2508	pIScsiPDUTx->cbSgLeft = sizeof(pIScsiPDUTx->aBHS);
2509	RTSgBufInit(&pIScsiPDUTx->SgBuf, pIScsiPDUTx->aISCSIReq, cnISCSIReq);
2510
2511	/*
2512	* Link the PDU to the list.
2513	* Insert at the front of the list to send the response as soon as possible
2514	* to avoid frequent reconnects for a slow connection when there are many PDUs
2515	* waiting.
2516	*/
2517	iscsiPDUTxAdd(pImage, pIScsiPDUTx, true /* fFront */);
2518
2519	/* Start transfer of a PDU if there is no one active at the moment. */
2520	if (!pImage->pIScsiPDUTxCur)
2521	rc = iscsiSendPDUAsync(pImage);
2522	}
2523	}
2524	} while (0);
2525	}
2526
2527	return rc;
2528	}
2529
2530	/**
2531	* Check the static (not dependent on the connection/session state) validity of an iSCSI response PDU.
2532	*
2533	* @returns VBOX status
2534	* @param paRes Pointer to array of iSCSI response sections.
2535	* @param cnRes Number of valid iSCSI response sections in the array.
2536	*/
2537	static int iscsiValidatePDU(PISCSIRES paRes, uint32_t cnRes)
2538	{
2539	const uint32_t *pcrgResBHS;
2540	uint32_t hw0;
2541	Assert(cnRes >= 1);
2542	Assert(paRes[0].cbSeg >= ISCSI_BHS_SIZE);
2543
2544	LogFlowFunc(("paRes=%#p cnRes=%u\n", paRes, cnRes));
2545
2546	pcrgResBHS = (const uint32_t *)(paRes[0].pvSeg);
2547	hw0 = RT_N2H_U32(pcrgResBHS[0]);
2548	switch (hw0 & ISCSIOP_MASK)
2549	{
2550	case ISCSIOP_NOP_IN:
2551	/* NOP-In responses must not be split into several PDUs nor it may contain
2552	* ping data for target-initiated pings nor may both task tags be valid task tags. */
2553	if ( (hw0 & ISCSI_FINAL_BIT) == 0
2554	\|\| ( RT_N2H_U32(pcrgResBHS[4]) == ISCSI_TASK_TAG_RSVD
2555	&& RT_N2H_U32(pcrgResBHS[1]) != 0)
2556	\|\| ( RT_N2H_U32(pcrgResBHS[4]) != ISCSI_TASK_TAG_RSVD
2557	&& RT_N2H_U32(pcrgResBHS[5]) != ISCSI_TASK_TAG_RSVD))
2558	return VERR_PARSE_ERROR;
2559	break;
2560	case ISCSIOP_SCSI_RES:
2561	/* SCSI responses must not be split into several PDUs nor must the residual
2562	* bits be contradicting each other nor may the residual bits be set for PDUs
2563	* containing anything else but a completed command response. Underflow
2564	* is no reason for declaring a PDU as invalid, as the target may choose
2565	* to return less data than we assume to get. */
2566	if ( (hw0 & ISCSI_FINAL_BIT) == 0
2567	\|\| ((hw0 & ISCSI_BI_READ_RESIDUAL_OVFL_BIT) && (hw0 & ISCSI_BI_READ_RESIDUAL_UNFL_BIT))
2568	\|\| ((hw0 & ISCSI_RESIDUAL_OVFL_BIT) && (hw0 & ISCSI_RESIDUAL_UNFL_BIT))
2569	\|\| ( ((hw0 & ISCSI_SCSI_RESPONSE_MASK) == 0)
2570	&& ((hw0 & ISCSI_SCSI_STATUS_MASK) == SCSI_STATUS_OK)
2571	&& (hw0 & ( ISCSI_BI_READ_RESIDUAL_OVFL_BIT \| ISCSI_BI_READ_RESIDUAL_UNFL_BIT
2572	\| ISCSI_RESIDUAL_OVFL_BIT))))
2573	return VERR_PARSE_ERROR;
2574	else
2575	LogFlowFunc(("good SCSI response, first word %#08x\n", RT_N2H_U32(pcrgResBHS[0])));
2576	break;
2577	case ISCSIOP_LOGIN_RES:
2578	/* Login responses must not contain contradicting transit and continue bits. */
2579	if ((hw0 & ISCSI_CONTINUE_BIT) && ((hw0 & ISCSI_TRANSIT_BIT) != 0))
2580	return VERR_PARSE_ERROR;
2581	break;
2582	case ISCSIOP_TEXT_RES:
2583	/* Text responses must not contain contradicting final and continue bits nor
2584	* may the final bit be set for PDUs containing a target transfer tag other than
2585	* the reserved transfer tag (and vice versa). */
2586	if ( (((hw0 & ISCSI_CONTINUE_BIT) && (hw0 & ISCSI_FINAL_BIT) != 0))
2587	\|\| (((hw0 & ISCSI_FINAL_BIT) && (RT_N2H_U32(pcrgResBHS[5]) != ISCSI_TASK_TAG_RSVD)))
2588	\|\| (((hw0 & ISCSI_FINAL_BIT) == 0) && (RT_N2H_U32(pcrgResBHS[5]) == ISCSI_TASK_TAG_RSVD)))
2589	return VERR_PARSE_ERROR;
2590	break;
2591	case ISCSIOP_SCSI_DATA_IN:
2592	/* SCSI Data-in responses must not contain contradicting residual bits when
2593	* status bit is set. */
2594	if ((hw0 & ISCSI_STATUS_BIT) && (hw0 & ISCSI_RESIDUAL_OVFL_BIT) && (hw0 & ISCSI_RESIDUAL_UNFL_BIT))
2595	return VERR_PARSE_ERROR;
2596	break;
2597	case ISCSIOP_LOGOUT_RES:
2598	/* Logout responses must not have the final bit unset and may not contain any
2599	* data or additional header segments. */
2600	if ( ((hw0 & ISCSI_FINAL_BIT) == 0)
2601	\|\| (RT_N2H_U32(pcrgResBHS[1]) != 0))
2602	return VERR_PARSE_ERROR;
2603	break;
2604	case ISCSIOP_ASYN_MSG:
2605	/* Asynchronous Messages must not have the final bit unset and may not contain
2606	* an initiator task tag. */
2607	if ( ((hw0 & ISCSI_FINAL_BIT) == 0)
2608	\|\| (RT_N2H_U32(pcrgResBHS[4]) != ISCSI_TASK_TAG_RSVD))
2609	return VERR_PARSE_ERROR;
2610	break;
2611	case ISCSIOP_SCSI_TASKMGMT_RES:
2612	case ISCSIOP_R2T:
2613	case ISCSIOP_REJECT:
2614	default:
2615	/* Do some logging, ignore PDU. */
2616	LogFlowFunc(("ignore unhandled PDU, first word %#08x\n", RT_N2H_U32(pcrgResBHS[0])));
2617	return VERR_PARSE_ERROR;
2618	}
2619	/* A target must not send PDUs with MaxCmdSN less than ExpCmdSN-1. */
2620
2621	if (serial_number_less(RT_N2H_U32(pcrgResBHS[8]), RT_N2H_U32(pcrgResBHS[7])-1))
2622	return VERR_PARSE_ERROR;
2623
2624	return VINF_SUCCESS;
2625	}
2626
2627
2628	/**
2629	* Prepares a PDU to transfer for the given command and adds it to the list.
2630	*/
2631	static int iscsiPDUTxPrepare(PISCSIIMAGE pImage, PISCSICMD pIScsiCmd)
2632	{
2633	int rc = VINF_SUCCESS;
2634	uint32_t *paReqBHS;
2635	size_t cbData = 0;
2636	size_t cbSegs = 0;
2637	PSCSIREQ pScsiReq;
2638	PISCSIPDUTX pIScsiPDU = NULL;
2639
2640	LogFlowFunc(("pImage=%#p pIScsiCmd=%#p\n", pImage, pIScsiCmd));
2641
2642	Assert(pIScsiCmd->enmCmdType == ISCSICMDTYPE_REQ);
2643
2644	pIScsiCmd->Itt = iscsiNewITT(pImage);
2645	pScsiReq = pIScsiCmd->CmdType.ScsiReq.pScsiReq;
2646
2647	if (pScsiReq->cT2ISegs)
2648	RTSgBufInit(&pScsiReq->SgBufT2I, pScsiReq->paT2ISegs, pScsiReq->cT2ISegs);
2649
2650	/*
2651	* Allocate twice as much entries as required for padding (worst case).
2652	* The additional segment is for the BHS.
2653	*/
2654	size_t cI2TSegs = 2*(pScsiReq->cI2TSegs + 1);
2655	pIScsiPDU = (PISCSIPDUTX)RTMemAllocZ(RT_OFFSETOF(ISCSIPDUTX, aISCSIReq[cI2TSegs]));
2656	if (!pIScsiPDU)
2657	return VERR_NO_MEMORY;
2658
2659	pIScsiPDU->pIScsiCmd = pIScsiCmd;
2660
2661	if (pScsiReq->enmXfer == SCSIXFER_FROM_TARGET)
2662	cbData = (uint32_t)pScsiReq->cbT2IData;
2663	else
2664	cbData = (uint32_t)pScsiReq->cbI2TData;
2665
2666	paReqBHS = pIScsiPDU->aBHS;
2667
2668	/* Setup the BHS. */
2669	paReqBHS[0] = RT_H2N_U32( ISCSI_FINAL_BIT \| ISCSI_TASK_ATTR_SIMPLE \| ISCSIOP_SCSI_CMD
2670	\| (pScsiReq->enmXfer << 21)); /* I=0,F=1,Attr=Simple */
2671	paReqBHS[1] = RT_H2N_U32(0x00000000 \| ((uint32_t)pScsiReq->cbI2TData & 0xffffff)); /* TotalAHSLength=0 */
2672	paReqBHS[2] = RT_H2N_U32(pImage->LUN >> 32);
2673	paReqBHS[3] = RT_H2N_U32(pImage->LUN & 0xffffffff);
2674	paReqBHS[4] = pIScsiCmd->Itt;
2675	paReqBHS[5] = RT_H2N_U32(cbData);
2676	paReqBHS[6] = RT_H2N_U32(pImage->CmdSN);
2677	paReqBHS[7] = RT_H2N_U32(pImage->ExpStatSN);
2678	memcpy(paReqBHS + 8, pScsiReq->pvCDB, pScsiReq->cbCDB);
2679
2680	pIScsiPDU->CmdSN = pImage->CmdSN;
2681	pImage->CmdSN++;
2682
2683	/* Setup the S/G buffers. */
2684	uint32_t cnISCSIReq = 0;
2685	pIScsiPDU->aISCSIReq[cnISCSIReq].cbSeg = sizeof(pIScsiPDU->aBHS);
2686	pIScsiPDU->aISCSIReq[cnISCSIReq].pvSeg = pIScsiPDU->aBHS;
2687	cnISCSIReq++;
2688	cbSegs = sizeof(pIScsiPDU->aBHS);
2689	/* Padding is not necessary for the BHS. */
2690
2691	if (pScsiReq->cbI2TData)
2692	{
2693	for (unsigned cSeg = 0; cSeg < pScsiReq->cI2TSegs; cSeg++)
2694	{
2695	Assert(cnISCSIReq < cI2TSegs);
2696	pIScsiPDU->aISCSIReq[cnISCSIReq].cbSeg = pScsiReq->paI2TSegs[cSeg].cbSeg;
2697	pIScsiPDU->aISCSIReq[cnISCSIReq].pvSeg = pScsiReq->paI2TSegs[cSeg].pvSeg;
2698	cbSegs += pScsiReq->paI2TSegs[cSeg].cbSeg;
2699	cnISCSIReq++;
2700
2701	/* Add padding if necessary. */
2702	if (pScsiReq->paI2TSegs[cSeg].cbSeg & 3)
2703	{
2704	Assert(cnISCSIReq < cI2TSegs);
2705	pIScsiPDU->aISCSIReq[cnISCSIReq].pvSeg = &pImage->aPadding[0];
2706	pIScsiPDU->aISCSIReq[cnISCSIReq].cbSeg = 4 - (pScsiReq->paI2TSegs[cSeg].cbSeg & 3);
2707	cbSegs += pIScsiPDU->aISCSIReq[cnISCSIReq].cbSeg;
2708	cnISCSIReq++;
2709	}
2710	}
2711	}
2712
2713	pIScsiPDU->cISCSIReq = cnISCSIReq;
2714	pIScsiPDU->cbSgLeft = cbSegs;
2715	RTSgBufInit(&pIScsiPDU->SgBuf, pIScsiPDU->aISCSIReq, cnISCSIReq);
2716
2717	/* Link the PDU to the list. */
2718	iscsiPDUTxAdd(pImage, pIScsiPDU, false /* fFront */);
2719
2720	/* Start transfer of a PDU if there is no one active at the moment. */
2721	if (!pImage->pIScsiPDUTxCur)
2722	rc = iscsiSendPDUAsync(pImage);
2723
2724	return rc;
2725	}
2726
2727
2728	/**
2729	* Updates the state of a request from the PDU we received.
2730	*
2731	* @return VBox status code.
2732	* @param pImage iSCSI connection state to use.
2733	* @param paRes Pointer to array of iSCSI response sections.
2734	* @param cnRes Number of valid iSCSI response sections in the array.
2735	*/
2736	static int iscsiRecvPDUUpdateRequest(PISCSIIMAGE pImage, PISCSIRES paRes, uint32_t cnRes)
2737	{
2738	int rc = VINF_SUCCESS;
2739	PISCSICMD pIScsiCmd;
2740	uint32_t *paResBHS;
2741
2742	LogFlowFunc(("pImage=%#p paRes=%#p cnRes=%u\n", pImage, paRes, cnRes));
2743
2744	Assert(cnRes == 1);
2745	Assert(paRes[0].cbSeg >= ISCSI_BHS_SIZE);
2746
2747	paResBHS = (uint32_t *)paRes[0].pvSeg;
2748
2749	pIScsiCmd = iscsiCmdGetFromItt(pImage, paResBHS[4]);
2750
2751	if (pIScsiCmd)
2752	{
2753	bool final = false;
2754	PSCSIREQ pScsiReq;
2755
2756	LogFlow(("Found SCSI command %#p for Itt=%#u\n", pIScsiCmd, paResBHS[4]));
2757
2758	Assert(pIScsiCmd->enmCmdType == ISCSICMDTYPE_REQ);
2759	pScsiReq = pIScsiCmd->CmdType.ScsiReq.pScsiReq;
2760
2761	final = !!(RT_N2H_U32(paResBHS[0]) & ISCSI_FINAL_BIT);
2762	ISCSIOPCODE cmd = (ISCSIOPCODE)(RT_N2H_U32(paResBHS[0]) & ISCSIOP_MASK);
2763	if (cmd == ISCSIOP_SCSI_RES)
2764	{
2765	/* This is the final PDU which delivers the status (and may be omitted if
2766	* the last Data-In PDU included successful completion status). Note
2767	* that ExpStatSN has been bumped already in iscsiRecvPDU. */
2768	if (!final \|\| ((RT_N2H_U32(paResBHS[0]) & 0x0000ff00) != 0) \|\| (RT_N2H_U32(paResBHS[6]) != pImage->ExpStatSN - 1))
2769	{
2770	/* SCSI Response in the wrong place or with a (target) failure. */
2771	LogFlow(("Wrong ExpStatSN value in PDU\n"));
2772	rc = VERR_PARSE_ERROR;
2773	}
2774	else
2775	{
2776	pScsiReq->status = RT_N2H_U32(paResBHS[0]) & 0x000000ff;
2777	size_t cbData = RT_N2H_U32(paResBHS[1]) & 0x00ffffff;
2778	void pvSense = (uint8_t )paRes[0].pvSeg + ISCSI_BHS_SIZE;
2779
2780	if (cbData >= 2)
2781	{
2782	uint32_t cbStat = RT_N2H_U32(((uint32_t *)pvSense)[0]) >> 16;
2783	if (cbStat + 2 > cbData)
2784	{
2785	rc = VERR_BUFFER_OVERFLOW;
2786	}
2787	else
2788	{
2789	/* Truncate sense data if it doesn't fit into the buffer. */
2790	pScsiReq->cbSense = RT_MIN(cbStat, pScsiReq->cbSense);
2791	memcpy(pScsiReq->pvSense, (uint8_t *)pvSense + 2,
2792	RT_MIN(paRes[0].cbSeg - ISCSI_BHS_SIZE - 2, pScsiReq->cbSense));
2793	}
2794	}
2795	else if (cbData == 1)
2796	rc = VERR_PARSE_ERROR;
2797	else
2798	pScsiReq->cbSense = 0;
2799	}
2800	iscsiCmdComplete(pImage, pIScsiCmd, rc);
2801	}
2802	else if (cmd == ISCSIOP_SCSI_DATA_IN)
2803	{
2804	/* A Data-In PDU carries some data that needs to be added to the received
2805	* data in response to the command. There may be both partial and complete
2806	* Data-In PDUs, so collect data until the status is included or the status
2807	* is sent in a separate SCSI Result frame (see above). */
2808	size_t cbData = RT_N2H_U32(paResBHS[1]) & 0x00ffffff;
2809	void pvData = (uint8_t )paRes[0].pvSeg + ISCSI_BHS_SIZE;
2810
2811	if (final && cbData > pScsiReq->cbT2IData)
2812	{
2813	/* The received PDU is bigger than what we requested.
2814	* Must not happen under normal circumstances and is a target error. */
2815	rc = VERR_BUFFER_OVERFLOW;
2816	}
2817	else
2818	{
2819	/* Copy data from the received PDU into the T2I segments. */
2820	size_t cbCopied = RTSgBufCopyFromBuf(&pScsiReq->SgBufT2I, pvData, cbData);
2821	Assert(cbCopied == cbData);
2822
2823	if (final && (RT_N2H_U32(paResBHS[0]) & ISCSI_STATUS_BIT) != 0)
2824	{
2825	pScsiReq->status = RT_N2H_U32(paResBHS[0]) & 0x000000ff;
2826	pScsiReq->cbSense = 0;
2827	iscsiCmdComplete(pImage, pIScsiCmd, VINF_SUCCESS);
2828	}
2829	}
2830	}
2831	else
2832	rc = VERR_PARSE_ERROR;
2833	}
2834
2835	/* Log any errors here but ignore the PDU. */
2836	if (RT_FAILURE(rc))
2837	{
2838	LogRel(("iSCSI: Received malformed PDU from target %s (rc=%Rrc), ignoring\n", pImage->pszTargetName, rc));
2839	rc = VINF_SUCCESS;
2840	}
2841
2842	return rc;
2843	}
2844
2845	/**
2846	* Appends a key-value pair to the buffer. Normal ASCII strings (cbValue == 0) and large binary values
2847	* of a given length (cbValue > 0) are directly supported. Other value types must be converted to ASCII
2848	* by the caller. Strings must be in UTF-8 encoding.
2849	*
2850	* @returns VBOX status
2851	* @param pbBuf Pointer to the key-value buffer.
2852	* @param cbBuf Length of the key-value buffer.
2853	* @param pcbBufCurr Currently used portion of the key-value buffer.
2854	* @param pszKey Pointer to a string containing the key.
2855	* @param pszValue Pointer to either a string containing the value or to a large binary value.
2856	* @param cbValue Length of the binary value if applicable.
2857	*/
2858	static int iscsiTextAddKeyValue(uint8_t pbBuf, size_t cbBuf, size_t pcbBufCurr, const char *pcszKey,
2859	const char *pcszValue, size_t cbValue)
2860	{
2861	size_t cbBufTmp = *pcbBufCurr;
2862	size_t cbKey = strlen(pcszKey);
2863	size_t cbValueEnc;
2864	uint8_t *pbCurr;
2865
2866	if (cbValue == 0)
2867	cbValueEnc = strlen(pcszValue);
2868	else
2869	cbValueEnc = cbValue * 2 + 2; /* 2 hex bytes per byte, 2 bytes prefix */
2870
2871	if (cbBuf < cbBufTmp + cbKey + 1 + cbValueEnc + 1)
2872	{
2873	/* Buffer would overflow, signal error. */
2874	return VERR_BUFFER_OVERFLOW;
2875	}
2876
2877	/*
2878	* Append a key=value pair (zero terminated string) to the end of the buffer.
2879	*/
2880	pbCurr = pbBuf + cbBufTmp;
2881	memcpy(pbCurr, pcszKey, cbKey);
2882	pbCurr += cbKey;
2883	*pbCurr++ = '=';
2884	if (cbValue == 0)
2885	{
2886	memcpy(pbCurr, pcszValue, cbValueEnc);
2887	pbCurr += cbValueEnc;
2888	}
2889	else
2890	{
2891	*pbCurr++ = '0';
2892	*pbCurr++ = 'x';
2893	for (uint32_t i = 0; i < cbValue; i++)
2894	{
2895	uint8_t b;
2896	b = pcszValue[i];
2897	*pbCurr++ = NUM_2_HEX(b >> 4);
2898	*pbCurr++ = NUM_2_HEX(b & 0xf);
2899	}
2900	}
2901	*pbCurr = '\0';
2902	*pcbBufCurr = cbBufTmp + cbKey + 1 + cbValueEnc + 1;
2903
2904	return VINF_SUCCESS;
2905	}
2906
2907
2908	/**
2909	* Retrieve the value for a given key from the key=value buffer.
2910	*
2911	* @returns VBOX status.
2912	* @param pbBuf Buffer containing key=value pairs.
2913	* @param cbBuf Length of buffer with key=value pairs.
2914	* @param pszKey Pointer to key for which to retrieve the value.
2915	* @param ppszValue Pointer to value string pointer.
2916	*/
2917	static int iscsiTextGetKeyValue(const uint8_t pbBuf, size_t cbBuf, const char pcszKey, const char **ppcszValue)
2918	{
2919	size_t cbKey = strlen(pcszKey);
2920
2921	while (cbBuf != 0)
2922	{
2923	size_t cbKeyValNull = strlen((const char *)pbBuf) + 1;
2924
2925	if (strncmp(pcszKey, (const char *)pbBuf, cbKey) == 0 && pbBuf[cbKey] == '=')
2926	{
2927	ppcszValue = (const char )(pbBuf + cbKey + 1);
2928	return VINF_SUCCESS;
2929	}
2930	pbBuf += cbKeyValNull;
2931	cbBuf -= cbKeyValNull;
2932	}
2933	return VERR_INVALID_NAME;
2934	}
2935
2936
2937	/**
2938	* Convert a long-binary value from a value string to the binary representation.
2939	*
2940	* @returns VBOX status
2941	* @param pszValue Pointer to a string containing the textual value representation.
2942	* @param pbValue Pointer to the value buffer for the binary value.
2943	* @param pcbValue In: length of value buffer, out: actual length of binary value.
2944	*/
2945	static int iscsiStrToBinary(const char pcszValue, uint8_t pbValue, size_t *pcbValue)
2946	{
2947	size_t cbValue = *pcbValue;
2948	char c1, c2, c3, c4;
2949	Assert(cbValue >= 1);
2950
2951	if (strlen(pcszValue) < 3)
2952	return VERR_PARSE_ERROR;
2953	if (*pcszValue++ != '0')
2954	return VERR_PARSE_ERROR;
2955	switch (*pcszValue++)
2956	{
2957	case 'x':
2958	case 'X':
2959	if (strlen(pcszValue) & 1)
2960	{
2961	c1 = *pcszValue++;
2962	*pbValue++ = HEX_2_NUM(c1);
2963	cbValue--;
2964	}
2965	while (*pcszValue != '\0')
2966	{
2967	if (cbValue == 0)
2968	return VERR_BUFFER_OVERFLOW;
2969	c1 = *pcszValue++;
2970	if ((c1 < '0' \|\| c1 > '9') && (c1 < 'a' \|\| c1 > 'f') && (c1 < 'A' \|\| c1 > 'F'))
2971	return VERR_PARSE_ERROR;
2972	c2 = *pcszValue++;
2973	if ((c2 < '0' \|\| c2 > '9') && (c2 < 'a' \|\| c2 > 'f') && (c2 < 'A' \|\| c2 > 'F'))
2974	return VERR_PARSE_ERROR;
2975	*pbValue++ = (HEX_2_NUM(c1) << 4) \| HEX_2_NUM(c2);
2976	cbValue--;
2977	}
2978	*pcbValue -= cbValue;
2979	break;
2980	case 'b':
2981	case 'B':
2982	if ((strlen(pcszValue) & 3) != 0)
2983	return VERR_PARSE_ERROR;
2984	while (*pcszValue != '\0')
2985	{
2986	uint32_t temp;
2987	if (cbValue == 0)
2988	return VERR_BUFFER_OVERFLOW;
2989	c1 = *pcszValue++;
2990	if ((c1 < 'A' \|\| c1 > 'Z') && (c1 < 'a' \|\| c1 >'z') && (c1 < '0' \|\| c1 > '9') && (c1 != '+') && (c1 != '/'))
2991	return VERR_PARSE_ERROR;
2992	c2 = *pcszValue++;
2993	if ((c2 < 'A' \|\| c2 > 'Z') && (c2 < 'a' \|\| c2 >'z') && (c2 < '0' \|\| c2 > '9') && (c2 != '+') && (c2 != '/'))
2994	return VERR_PARSE_ERROR;
2995	c3 = *pcszValue++;
2996	if ((c3 < 'A' \|\| c3 > 'Z') && (c3 < 'a' \|\| c3 >'z') && (c3 < '0' \|\| c3 > '9') && (c3 != '+') && (c3 != '/') && (c3 != '='))
2997	return VERR_PARSE_ERROR;
2998	c4 = *pcszValue++;
2999	if ( (c3 == '=' && c4 != '=')
3000	\|\| ((c4 < 'A' \|\| c4 > 'Z') && (c4 < 'a' \|\| c4 >'z') && (c4 < '0' \|\| c4 > '9') && (c4 != '+') && (c4 != '/') && (c4 != '=')))
3001	return VERR_PARSE_ERROR;
3002	temp = (B64_2_NUM(c1) << 18) \| (B64_2_NUM(c2) << 12);
3003	if (c3 == '=') {
3004	if (*pcszValue != '\0')
3005	return VERR_PARSE_ERROR;
3006	*pbValue++ = temp >> 16;
3007	cbValue--;
3008	} else {
3009	temp \|= B64_2_NUM(c3) << 6;
3010	if (c4 == '=') {
3011	if (*pcszValue != '\0')
3012	return VERR_PARSE_ERROR;
3013	if (cbValue < 2)
3014	return VERR_BUFFER_OVERFLOW;
3015	*pbValue++ = temp >> 16;
3016	*pbValue++ = (temp >> 8) & 0xff;
3017	cbValue -= 2;
3018	}
3019	else
3020	{
3021	temp \|= B64_2_NUM(c4);
3022	if (cbValue < 3)
3023	return VERR_BUFFER_OVERFLOW;
3024	*pbValue++ = temp >> 16;
3025	*pbValue++ = (temp >> 8) & 0xff;
3026	*pbValue++ = temp & 0xff;
3027	cbValue -= 3;
3028	}
3029	}
3030	}
3031	*pcbValue -= cbValue;
3032	break;
3033	default:
3034	return VERR_PARSE_ERROR;
3035	}
3036	return VINF_SUCCESS;
3037	}
3038
3039
3040	/**
3041	* Retrieve the relevant parameter values and update the initiator state.
3042	*
3043	* @returns VBOX status.
3044	* @param pImage Current iSCSI initiator state.
3045	* @param pbBuf Buffer containing key=value pairs.
3046	* @param cbBuf Length of buffer with key=value pairs.
3047	*/
3048	static int iscsiUpdateParameters(PISCSIIMAGE pImage, const uint8_t *pbBuf, size_t cbBuf)
3049	{
3050	int rc;
3051	const char *pcszMaxRecvDataSegmentLength = NULL;
3052	const char *pcszMaxBurstLength = NULL;
3053	const char *pcszFirstBurstLength = NULL;
3054	rc = iscsiTextGetKeyValue(pbBuf, cbBuf, "MaxRecvDataSegmentLength", &pcszMaxRecvDataSegmentLength);
3055	if (rc == VERR_INVALID_NAME)
3056	rc = VINF_SUCCESS;
3057	if (RT_FAILURE(rc))
3058	return VERR_PARSE_ERROR;
3059	rc = iscsiTextGetKeyValue(pbBuf, cbBuf, "MaxBurstLength", &pcszMaxBurstLength);
3060	if (rc == VERR_INVALID_NAME)
3061	rc = VINF_SUCCESS;
3062	if (RT_FAILURE(rc))
3063	return VERR_PARSE_ERROR;
3064	rc = iscsiTextGetKeyValue(pbBuf, cbBuf, "FirstBurstLength", &pcszFirstBurstLength);
3065	if (rc == VERR_INVALID_NAME)
3066	rc = VINF_SUCCESS;
3067	if (RT_FAILURE(rc))
3068	return VERR_PARSE_ERROR;
3069	if (pcszMaxRecvDataSegmentLength)
3070	{
3071	uint32_t cb = pImage->cbSendDataLength;
3072	rc = RTStrToUInt32Full(pcszMaxRecvDataSegmentLength, 0, &cb);
3073	AssertRC(rc);
3074	pImage->cbSendDataLength = RT_MIN(pImage->cbSendDataLength, cb);
3075	}
3076	if (pcszMaxBurstLength)
3077	{
3078	uint32_t cb = pImage->cbSendDataLength;
3079	rc = RTStrToUInt32Full(pcszMaxBurstLength, 0, &cb);
3080	AssertRC(rc);
3081	pImage->cbSendDataLength = RT_MIN(pImage->cbSendDataLength, cb);
3082	}
3083	if (pcszFirstBurstLength)
3084	{
3085	uint32_t cb = pImage->cbSendDataLength;
3086	rc = RTStrToUInt32Full(pcszFirstBurstLength, 0, &cb);
3087	AssertRC(rc);
3088	pImage->cbSendDataLength = RT_MIN(pImage->cbSendDataLength, cb);
3089	}
3090	return VINF_SUCCESS;
3091	}
3092
3093
3094	static bool serial_number_less(uint32_t s1, uint32_t s2)
3095	{
3096	return (s1 < s2 && s2 - s1 < 0x80000000) \|\| (s1 > s2 && s1 - s2 > 0x80000000);
3097	}
3098
3099	static bool serial_number_greater(uint32_t s1, uint32_t s2)
3100	{
3101	return (s1 < s2 && s2 - s1 > 0x80000000) \|\| (s1 > s2 && s1 - s2 < 0x80000000);
3102	}
3103
3104
3105	#ifdef IMPLEMENT_TARGET_AUTH
3106	static void chap_md5_generate_challenge(uint8_t pbChallenge, size_t pcbChallenge)
3107	{
3108	uint8_t cbChallenge;
3109
3110	cbChallenge = RTrand_U8(CHAP_MD5_CHALLENGE_MIN, CHAP_MD5_CHALLENGE_MAX);
3111	RTrand_bytes(pbChallenge, cbChallenge);
3112	*pcbChallenge = cbChallenge;
3113	}
3114	#endif
3115
3116
3117	static void chap_md5_compute_response(uint8_t pbResponse, uint8_t id, const uint8_t pbChallenge, size_t cbChallenge,
3118	const uint8_t *pbSecret, size_t cbSecret)
3119	{
3120	RTMD5CONTEXT ctx;
3121	uint8_t bId;
3122
3123	bId = id;
3124	RTMd5Init(&ctx);
3125	RTMd5Update(&ctx, &bId, 1);
3126	RTMd5Update(&ctx, pbSecret, cbSecret);
3127	RTMd5Update(&ctx, pbChallenge, cbChallenge);
3128	RTMd5Final(pbResponse, &ctx);
3129	}
3130
3131	/**
3132	* Internal. - Wrapper around the extended select callback of the net interface.
3133	*/
3134	DECLINLINE(int) iscsiIoThreadWait(PISCSIIMAGE pImage, RTMSINTERVAL cMillies, uint32_t fEvents, uint32_t *pfEvents)
3135	{
3136	return pImage->pIfNet->pfnSelectOneEx(pImage->Socket, fEvents, pfEvents, cMillies);
3137	}
3138
3139	/**
3140	* Internal. - Pokes a thread waiting for I/O.
3141	*/
3142	DECLINLINE(int) iscsiIoThreadPoke(PISCSIIMAGE pImage)
3143	{
3144	return pImage->pIfNet->pfnPoke(pImage->Socket);
3145	}
3146
3147	/**
3148	* Internal. - Get the next request from the queue.
3149	*/
3150	DECLINLINE(PISCSICMD) iscsiCmdGet(PISCSIIMAGE pImage)
3151	{
3152	int rc;
3153	PISCSICMD pIScsiCmd = NULL;
3154
3155	rc = RTSemMutexRequest(pImage->MutexReqQueue, RT_INDEFINITE_WAIT);
3156	AssertRC(rc);
3157
3158	pIScsiCmd = pImage->pScsiReqQueue;
3159	if (pIScsiCmd)
3160	{
3161	pImage->pScsiReqQueue = pIScsiCmd->pNext;
3162	pIScsiCmd->pNext = NULL;
3163	}
3164
3165	rc = RTSemMutexRelease(pImage->MutexReqQueue);
3166	AssertRC(rc);
3167
3168	return pIScsiCmd;
3169	}
3170
3171
3172	/**
3173	* Internal. - Adds the given command to the queue.
3174	*/
3175	DECLINLINE(int) iscsiCmdPut(PISCSIIMAGE pImage, PISCSICMD pIScsiCmd)
3176	{
3177	int rc = RTSemMutexRequest(pImage->MutexReqQueue, RT_INDEFINITE_WAIT);
3178	AssertRC(rc);
3179
3180	pIScsiCmd->pNext = pImage->pScsiReqQueue;
3181	pImage->pScsiReqQueue = pIScsiCmd;
3182
3183	rc = RTSemMutexRelease(pImage->MutexReqQueue);
3184	AssertRC(rc);
3185
3186	iscsiIoThreadPoke(pImage);
3187
3188	return rc;
3189	}
3190
3191	/**
3192	* Internal. - Completes the request with the appropriate action.
3193	* Synchronous requests are completed with waking up the thread
3194	* and asynchronous ones by continuing the associated I/O context.
3195	*/
3196	static void iscsiCmdComplete(PISCSIIMAGE pImage, PISCSICMD pIScsiCmd, int rcCmd)
3197	{
3198	LogFlowFunc(("pImage=%#p pIScsiCmd=%#p rcCmd=%Rrc\n", pImage, pIScsiCmd, rcCmd));
3199
3200	/* Remove from the table first. */
3201	iscsiCmdRemove(pImage, pIScsiCmd->Itt);
3202
3203	/* Call completion callback. */
3204	pIScsiCmd->pfnComplete(pImage, rcCmd, pIScsiCmd->pvUser);
3205
3206	/* Free command structure. */
3207	#ifdef DEBUG
3208	memset(pIScsiCmd, 0xff, sizeof(ISCSICMD));
3209	#endif
3210	RTMemFree(pIScsiCmd);
3211	}
3212
3213	/**
3214	* Reattaches the to the target after an error aborting
3215	* pending commands and resending them.
3216	*
3217	* @param pImage iSCSI connection state.
3218	*/
3219	static void iscsiReattach(PISCSIIMAGE pImage)
3220	{
3221	int rc = VINF_SUCCESS;
3222	PISCSICMD pIScsiCmdHead = NULL;
3223	PISCSICMD pIScsiCmd = NULL;
3224	PISCSICMD pIScsiCmdCur = NULL;
3225	PISCSIPDUTX pIScsiPDUTx = NULL;
3226
3227	/* Close connection. */
3228	iscsiTransportClose(pImage);
3229	pImage->state = ISCSISTATE_FREE;
3230
3231	/* Reset PDU we are receiving. */
3232	iscsiRecvPDUReset(pImage);
3233
3234	/*
3235	* Abort all PDUs we are about to transmit,
3236	* the command need a new Itt if the relogin is successful.
3237	*/
3238	while (pImage->pIScsiPDUTxHead)
3239	{
3240	pIScsiPDUTx = pImage->pIScsiPDUTxHead;
3241	pImage->pIScsiPDUTxHead = pIScsiPDUTx->pNext;
3242
3243	pIScsiCmd = pIScsiPDUTx->pIScsiCmd;
3244
3245	if (pIScsiCmd)
3246	{
3247	/* Place on command list. */
3248	pIScsiCmd->pNext = pIScsiCmdHead;
3249	pIScsiCmdHead = pIScsiCmd;
3250	}
3251	RTMemFree(pIScsiPDUTx);
3252	}
3253
3254	/* Clear the tail pointer (safety precaution). */
3255	pImage->pIScsiPDUTxTail = NULL;
3256
3257	/* Clear the current PDU too. */
3258	if (pImage->pIScsiPDUTxCur)
3259	{
3260	pIScsiPDUTx = pImage->pIScsiPDUTxCur;
3261
3262	pImage->pIScsiPDUTxCur = NULL;
3263	pIScsiCmd = pIScsiPDUTx->pIScsiCmd;
3264
3265	if (pIScsiCmd)
3266	{
3267	pIScsiCmd->pNext = pIScsiCmdHead;
3268	pIScsiCmdHead = pIScsiCmd;
3269	}
3270	RTMemFree(pIScsiPDUTx);
3271	}
3272
3273	/*
3274	* Get all commands which are waiting for a response
3275	* They need to be resend too after a successful reconnect.
3276	*/
3277	pIScsiCmd = iscsiCmdRemoveAll(pImage);
3278
3279	if (pIScsiCmd)
3280	{
3281	pIScsiCmdCur = pIScsiCmd;
3282	while (pIScsiCmdCur->pNext)
3283	pIScsiCmdCur = pIScsiCmdCur->pNext;
3284
3285	/*
3286	* Place them in front of the list because they are the oldest requests
3287	* and need to be processed first to minimize the risk to time out.
3288	*/
3289	pIScsiCmdCur->pNext = pIScsiCmdHead;
3290	pIScsiCmdHead = pIScsiCmd;
3291	}
3292
3293	/* Try to attach. */
3294	rc = iscsiAttach(pImage);
3295	if (RT_SUCCESS(rc))
3296	{
3297	/* Phew, we have a connection again.
3298	* Prepare new PDUs for the aborted commands.
3299	*/
3300	while (pIScsiCmdHead)
3301	{
3302	pIScsiCmd = pIScsiCmdHead;
3303	pIScsiCmdHead = pIScsiCmdHead->pNext;
3304
3305	pIScsiCmd->pNext = NULL;
3306
3307	rc = iscsiPDUTxPrepare(pImage, pIScsiCmd);
3308	AssertRC(rc);
3309	}
3310	}
3311	else
3312	{
3313	/*
3314	* Still no luck, complete commands with error so the caller
3315	* has a chance to inform the user and maybe resend the command.
3316	*/
3317	while (pIScsiCmdHead)
3318	{
3319	pIScsiCmd = pIScsiCmdHead;
3320	pIScsiCmdHead = pIScsiCmdHead->pNext;
3321
3322	iscsiCmdComplete(pImage, pIScsiCmd, VERR_BROKEN_PIPE);
3323	}
3324	}
3325	}
3326
3327	/**
3328	* Internal. Main iSCSI I/O worker.
3329	*/
3330	static DECLCALLBACK(int) iscsiIoThreadWorker(RTTHREAD ThreadSelf, void *pvUser)
3331	{
3332	PISCSIIMAGE pImage = (PISCSIIMAGE)pvUser;
3333
3334	/* Initialize the initial event mask. */
3335	pImage->fPollEvents = VD_INTERFACETCPNET_EVT_READ \| VD_INTERFACETCPNET_EVT_ERROR;
3336
3337	while (pImage->fRunning)
3338	{
3339	uint32_t fEvents;
3340	int rc;
3341
3342	fEvents = 0;
3343
3344	/* Wait for work or for data from the target. */
3345	RTMSINTERVAL msWait;
3346
3347	if (pImage->cCmdsWaiting)
3348	{
3349	pImage->fPollEvents &= ~VD_INTERFACETCPNET_HINT_INTERRUPT;
3350	msWait = pImage->uReadTimeout;
3351	}
3352	else
3353	{
3354	pImage->fPollEvents \|= VD_INTERFACETCPNET_HINT_INTERRUPT;
3355	msWait = RT_INDEFINITE_WAIT;
3356	}
3357
3358	LogFlow(("Waiting for events fPollEvents=%#x\n", pImage->fPollEvents));
3359	rc = iscsiIoThreadWait(pImage, msWait, pImage->fPollEvents, &fEvents);
3360	if (rc == VERR_INTERRUPTED)
3361	{
3362	/* Check the queue. */
3363	PISCSICMD pIScsiCmd = iscsiCmdGet(pImage);
3364
3365	while (pIScsiCmd)
3366	{
3367	switch (pIScsiCmd->enmCmdType)
3368	{
3369	case ISCSICMDTYPE_REQ:
3370	{
3371	/* If there is no connection complete the command with an error. */
3372	if (RT_LIKELY(iscsiIsClientConnected(pImage)))
3373	{
3374	rc = iscsiPDUTxPrepare(pImage, pIScsiCmd);
3375	AssertRC(rc);
3376	}
3377	else
3378	iscsiCmdComplete(pImage, pIScsiCmd, VERR_NET_CONNECTION_REFUSED);
3379	break;
3380	}
3381	case ISCSICMDTYPE_EXEC:
3382	{
3383	rc = pIScsiCmd->CmdType.Exec.pfnExec(pIScsiCmd->CmdType.Exec.pvUser);
3384	iscsiCmdComplete(pImage, pIScsiCmd, rc);
3385	break;
3386	}
3387	default:
3388	AssertMsgFailed(("Invalid command type %d\n", pIScsiCmd->enmCmdType));
3389	}
3390
3391	pIScsiCmd = iscsiCmdGet(pImage);
3392	}
3393	}
3394	else if (rc == VERR_TIMEOUT && pImage->cCmdsWaiting)
3395	{
3396	/*
3397	* We are waiting for a response from the target but
3398	* it didn't answered yet.
3399	* We assume the connection is broken and try to reconnect.
3400	*/
3401	LogFlow(("Timed out while waiting for an answer from the target, reconnecting\n"));
3402	iscsiReattach(pImage);
3403	}
3404	else if (RT_SUCCESS(rc) \|\| rc == VERR_TIMEOUT)
3405	{
3406	Assert(pImage->state == ISCSISTATE_NORMAL);
3407	LogFlow(("Got socket events %#x\n", fEvents));
3408
3409	if (fEvents & VD_INTERFACETCPNET_EVT_READ)
3410	{
3411	/* Continue or start a new PDU receive task */
3412	LogFlow(("There is data on the socket\n"));
3413	rc = iscsiRecvPDUAsync(pImage);
3414	if (rc == VERR_BROKEN_PIPE)
3415	iscsiReattach(pImage);
3416	else if (RT_FAILURE(rc))
3417	iscsiLogRel(pImage, "iSCSI: Handling incoming request failed %Rrc\n", rc);
3418	}
3419
3420	if (fEvents & VD_INTERFACETCPNET_EVT_WRITE)
3421	{
3422	LogFlow(("The socket is writable\n"));
3423	rc = iscsiSendPDUAsync(pImage);
3424	if (RT_FAILURE(rc))
3425	{
3426	/*
3427	* Something unexpected happened, log the error and try to reset everything
3428	* by reattaching to the target.
3429	*/
3430	iscsiLogRel(pImage, "iSCSI: Sending PDU failed %Rrc\n", rc);
3431	iscsiReattach(pImage);
3432	}
3433	}
3434
3435	if (fEvents & VD_INTERFACETCPNET_EVT_ERROR)
3436	{
3437	LogFlow(("An error ocurred\n"));
3438	iscsiReattach(pImage);
3439	}
3440	}
3441	else
3442	iscsiLogRel(pImage, "iSCSI: Waiting for I/O failed rc=%Rrc\n", rc);
3443	}
3444
3445	return VINF_SUCCESS;
3446	}
3447
3448	/**
3449	* Internal. - Enqueues a request asynchronously.
3450	*/
3451	static int iscsiCommandAsync(PISCSIIMAGE pImage, PSCSIREQ pScsiReq,
3452	PFNISCSICMDCOMPLETED pfnComplete, void *pvUser)
3453	{
3454	int rc;
3455
3456	if (pImage->fExtendedSelectSupported)
3457	{
3458	PISCSICMD pIScsiCmd = (PISCSICMD)RTMemAllocZ(sizeof(ISCSICMD));
3459	if (!pIScsiCmd)
3460	return VERR_NO_MEMORY;
3461
3462	/* Init the command structure. */
3463	pIScsiCmd->pNext = NULL;
3464	pIScsiCmd->enmCmdType = ISCSICMDTYPE_REQ;
3465	pIScsiCmd->pfnComplete = pfnComplete;
3466	pIScsiCmd->pvUser = pvUser;
3467	pIScsiCmd->CmdType.ScsiReq.pScsiReq = pScsiReq;
3468
3469	rc = iscsiCmdPut(pImage, pIScsiCmd);
3470	if (RT_FAILURE(rc))
3471	RTMemFree(pIScsiCmd);
3472	}
3473	else
3474	rc = VERR_NOT_SUPPORTED;
3475
3476	return rc;
3477	}
3478
3479	static void iscsiCommandCompleteSync(PISCSIIMAGE pImage, int rcReq, void *pvUser)
3480	{
3481	PISCSICMDSYNC pIScsiCmdSync = (PISCSICMDSYNC)pvUser;
3482
3483	pIScsiCmdSync->rcCmd = rcReq;
3484	int rc = RTSemEventSignal(pIScsiCmdSync->EventSem);
3485	AssertRC(rc);
3486	}
3487
3488	/**
3489	* Internal. - Enqueues a request in a synchronous fashion
3490	* i.e. returns when the request completed.
3491	*/
3492	static int iscsiCommandSync(PISCSIIMAGE pImage, PSCSIREQ pScsiReq, bool fRetry, int rcSense)
3493	{
3494	int rc;
3495
3496	if (pImage->fExtendedSelectSupported)
3497	{
3498	ISCSICMDSYNC IScsiCmdSync;
3499
3500	/* Create event semaphore. */
3501	rc = RTSemEventCreate(&IScsiCmdSync.EventSem);
3502	if (RT_FAILURE(rc))
3503	return rc;
3504
3505	if (fRetry)
3506	{
3507	for (unsigned i = 0; i < 10; i++)
3508	{
3509	rc = iscsiCommandAsync(pImage, pScsiReq, iscsiCommandCompleteSync, &IScsiCmdSync);
3510	if (RT_FAILURE(rc))
3511	break;
3512
3513	rc = RTSemEventWait(IScsiCmdSync.EventSem, RT_INDEFINITE_WAIT);
3514	AssertRC(rc);
3515	rc = IScsiCmdSync.rcCmd;
3516
3517	if ( (RT_SUCCESS(rc) && !pScsiReq->cbSense)
3518	\|\| RT_FAILURE(rc))
3519	break;
3520	rc = rcSense;
3521	}
3522	}
3523	else
3524	{
3525	rc = iscsiCommandAsync(pImage, pScsiReq, iscsiCommandCompleteSync, &IScsiCmdSync);
3526	if (RT_SUCCESS(rc))
3527	{
3528	rc = RTSemEventWait(IScsiCmdSync.EventSem, RT_INDEFINITE_WAIT);
3529	AssertRC(rc);
3530	rc = IScsiCmdSync.rcCmd;
3531
3532	if (RT_FAILURE(rc) \|\| pScsiReq->cbSense > 0)
3533	rc = rcSense;
3534	}
3535	}
3536
3537	RTSemEventDestroy(IScsiCmdSync.EventSem);
3538	}
3539	else
3540	{
3541	if (fRetry)
3542	{
3543	for (unsigned i = 0; i < 10; i++)
3544	{
3545	rc = iscsiCommand(pImage, pScsiReq);
3546	if ( (RT_SUCCESS(rc) && !pScsiReq->cbSense)
3547	\|\| RT_FAILURE(rc))
3548	break;
3549	rc = rcSense;
3550	}
3551	}
3552	else
3553	{
3554	rc = iscsiCommand(pImage, pScsiReq);
3555	if (RT_SUCCESS(rc) && pScsiReq->cbSense > 0)
3556	rc = rcSense;
3557	}
3558	}
3559
3560	return rc;
3561	}
3562
3563
3564	/**
3565	* Internal. - Executes a given function in a synchronous fashion
3566	* on the I/O thread if available.
3567	*/
3568	static int iscsiExecSync(PISCSIIMAGE pImage, PFNISCSIEXEC pfnExec, void *pvUser)
3569	{
3570	int rc;
3571
3572	if (pImage->fExtendedSelectSupported)
3573	{
3574	ISCSICMDSYNC IScsiCmdSync;
3575	PISCSICMD pIScsiCmd = (PISCSICMD)RTMemAllocZ(sizeof(ISCSICMD));
3576	if (!pIScsiCmd)
3577	return VERR_NO_MEMORY;
3578
3579	/* Create event semaphore. */
3580	rc = RTSemEventCreate(&IScsiCmdSync.EventSem);
3581	if (RT_FAILURE(rc))
3582	{
3583	RTMemFree(pIScsiCmd);
3584	return rc;
3585	}
3586
3587	/* Init the command structure. */
3588	pIScsiCmd->pNext = NULL;
3589	pIScsiCmd->enmCmdType = ISCSICMDTYPE_EXEC;
3590	pIScsiCmd->pfnComplete = iscsiCommandCompleteSync;
3591	pIScsiCmd->pvUser = &IScsiCmdSync;
3592	pIScsiCmd->CmdType.Exec.pfnExec = pfnExec;
3593	pIScsiCmd->CmdType.Exec.pvUser = pvUser;
3594
3595	rc = iscsiCmdPut(pImage, pIScsiCmd);
3596	if (RT_FAILURE(rc))
3597	RTMemFree(pIScsiCmd);
3598	else
3599	{
3600	rc = RTSemEventWait(IScsiCmdSync.EventSem, RT_INDEFINITE_WAIT);
3601	AssertRC(rc);
3602	rc = IScsiCmdSync.rcCmd;
3603	}
3604
3605	RTSemEventDestroy(IScsiCmdSync.EventSem);
3606	}
3607	else
3608	{
3609	/* No I/O thread, execute in the current thread. */
3610	rc = pfnExec(pvUser);
3611	}
3612
3613	return rc;
3614	}
3615
3616
3617	static void iscsiCommandAsyncComplete(PISCSIIMAGE pImage, int rcReq, void *pvUser)
3618	{
3619	bool fComplete = true;
3620	size_t cbTransfered = 0;
3621	PSCSIREQASYNC pReqAsync = (PSCSIREQASYNC)pvUser;
3622	PSCSIREQ pScsiReq = pReqAsync->pScsiReq;
3623
3624	if ( RT_SUCCESS(rcReq)
3625	&& pScsiReq->cbSense > 0)
3626	{
3627	/* Try again if possible. */
3628	if (pReqAsync->cSenseRetries > 0)
3629	{
3630	pReqAsync->cSenseRetries--;
3631	pScsiReq->cbSense = sizeof(pReqAsync->abSense);
3632	int rc = iscsiCommandAsync(pImage, pScsiReq, iscsiCommandAsyncComplete, pReqAsync);
3633	if (RT_SUCCESS(rc))
3634	fComplete = false;
3635	else
3636	rcReq = pReqAsync->rcSense;
3637	}
3638	else
3639	rcReq = pReqAsync->rcSense;
3640	}
3641
3642	if (fComplete)
3643	{
3644	if (pScsiReq->enmXfer == SCSIXFER_FROM_TARGET)
3645	cbTransfered = pScsiReq->cbT2IData;
3646	else if (pScsiReq->enmXfer == SCSIXFER_TO_TARGET)
3647	cbTransfered = pScsiReq->cbI2TData;
3648	else
3649	AssertMsg(pScsiReq->enmXfer == SCSIXFER_NONE, ("To/From transfers are not supported yet\n"));
3650
3651	/* Continue I/O context. */
3652	pImage->pIfIo->pfnIoCtxCompleted(pImage->pIfIo->Core.pvUser,
3653	pReqAsync->pIoCtx, rcReq,
3654	cbTransfered);
3655
3656	RTMemFree(pScsiReq);
3657	RTMemFree(pReqAsync);
3658	}
3659	}
3660
3661
3662	/**
3663	* Internal. Free all allocated space for representing an image, and optionally
3664	* delete the image from disk.
3665	*/
3666	static int iscsiFreeImage(PISCSIIMAGE pImage, bool fDelete)
3667	{
3668	int rc = VINF_SUCCESS;
3669	Assert(!fDelete); /* This MUST be false, the flag isn't supported. */
3670
3671	/* Freeing a never allocated image (e.g. because the open failed) is
3672	* not signalled as an error. After all nothing bad happens. */
3673	if (pImage)
3674	{
3675	if (pImage->Mutex != NIL_RTSEMMUTEX)
3676	{
3677	/* Detaching only makes sense when the mutex is there. Otherwise the
3678	* failure happened long before we could attach to the target. */
3679	iscsiExecSync(pImage, iscsiDetach, pImage);
3680	RTSemMutexDestroy(pImage->Mutex);
3681	pImage->Mutex = NIL_RTSEMMUTEX;
3682	}
3683	if (pImage->hThreadIo != NIL_RTTHREAD)
3684	{
3685	ASMAtomicXchgBool(&pImage->fRunning, false);
3686	rc = iscsiIoThreadPoke(pImage);
3687	AssertRC(rc);
3688
3689	/* Wait for the thread to terminate. */
3690	rc = RTThreadWait(pImage->hThreadIo, RT_INDEFINITE_WAIT, NULL);
3691	AssertRC(rc);
3692	}
3693	/* Destroy the socket. */
3694	if (pImage->Socket != NIL_VDSOCKET)
3695	{
3696	pImage->pIfNet->pfnSocketDestroy(pImage->Socket);
3697	}
3698	if (pImage->MutexReqQueue != NIL_RTSEMMUTEX)
3699	{
3700	RTSemMutexDestroy(pImage->MutexReqQueue);
3701	pImage->MutexReqQueue = NIL_RTSEMMUTEX;
3702	}
3703	if (pImage->pszTargetName)
3704	{
3705	RTMemFree(pImage->pszTargetName);
3706	pImage->pszTargetName = NULL;
3707	}
3708	if (pImage->pszInitiatorName)
3709	{
3710	if (pImage->fAutomaticInitiatorName)
3711	RTStrFree(pImage->pszInitiatorName);
3712	else
3713	RTMemFree(pImage->pszInitiatorName);
3714	pImage->pszInitiatorName = NULL;
3715	}
3716	if (pImage->pszInitiatorUsername)
3717	{
3718	RTMemFree(pImage->pszInitiatorUsername);
3719	pImage->pszInitiatorUsername = NULL;
3720	}
3721	if (pImage->pbInitiatorSecret)
3722	{
3723	RTMemFree(pImage->pbInitiatorSecret);
3724	pImage->pbInitiatorSecret = NULL;
3725	}
3726	if (pImage->pszTargetUsername)
3727	{
3728	RTMemFree(pImage->pszTargetUsername);
3729	pImage->pszTargetUsername = NULL;
3730	}
3731	if (pImage->pbTargetSecret)
3732	{
3733	RTMemFree(pImage->pbTargetSecret);
3734	pImage->pbTargetSecret = NULL;
3735	}
3736	if (pImage->pvRecvPDUBuf)
3737	{
3738	RTMemFree(pImage->pvRecvPDUBuf);
3739	pImage->pvRecvPDUBuf = NULL;
3740	}
3741
3742	pImage->cbRecvPDUResidual = 0;
3743	}
3744
3745	LogFlowFunc(("returns %Rrc\n", rc));
3746	return rc;
3747	}
3748
3749	/**
3750	* Internal: Open an image, constructing all necessary data structures.
3751	*/
3752	static int iscsiOpenImage(PISCSIIMAGE pImage, unsigned uOpenFlags)
3753	{
3754	int rc;
3755	char pszLUN = NULL, pszLUNInitial = NULL;
3756	bool fLunEncoded = false;
3757	uint32_t uWriteSplitDef = 0;
3758	uint32_t uTimeoutDef = 0;
3759	uint64_t uHostIPTmp = 0;
3760	bool fHostIPDef = 0;
3761	rc = RTStrToUInt32Full(s_iscsiConfigDefaultWriteSplit, 0, &uWriteSplitDef);
3762	AssertRC(rc);
3763	rc = RTStrToUInt32Full(s_iscsiConfigDefaultTimeout, 0, &uTimeoutDef);
3764	AssertRC(rc);
3765	rc = RTStrToUInt64Full(s_iscsiConfigDefaultHostIPStack, 0, &uHostIPTmp);
3766	AssertRC(rc);
3767	fHostIPDef = !!uHostIPTmp;
3768
3769	pImage->uOpenFlags = uOpenFlags;
3770
3771	/* Get error signalling interface. */
3772	pImage->pIfError = VDIfErrorGet(pImage->pVDIfsDisk);
3773
3774	/* Get TCP network stack interface. */
3775	pImage->pIfNet = VDIfTcpNetGet(pImage->pVDIfsImage);
3776	if (!pImage->pIfNet)
3777	{
3778	rc = vdIfError(pImage->pIfError, VERR_VD_ISCSI_UNKNOWN_INTERFACE,
3779	RT_SRC_POS, N_("iSCSI: TCP network stack interface missing"));
3780	goto out;
3781	}
3782
3783	/* Get configuration interface. */
3784	pImage->pIfConfig = VDIfConfigGet(pImage->pVDIfsImage);
3785	if (!pImage->pIfConfig)
3786	{
3787	rc = vdIfError(pImage->pIfError, VERR_VD_ISCSI_UNKNOWN_INTERFACE,
3788	RT_SRC_POS, N_("iSCSI: configuration interface missing"));
3789	goto out;
3790	}
3791
3792	/* Get I/O interface. */
3793	pImage->pIfIo = VDIfIoIntGet(pImage->pVDIfsImage);
3794	if (!pImage->pIfIo)
3795	{
3796	rc = vdIfError(pImage->pIfError, VERR_VD_ISCSI_UNKNOWN_INTERFACE,
3797	RT_SRC_POS, N_("iSCSI: I/O interface missing"));
3798	goto out;
3799	}
3800
3801	/* This ISID will be adjusted later to make it unique on this host. */
3802	pImage->ISID = 0x800000000000ULL \| 0x001234560000ULL;
3803	pImage->cISCSIRetries = 10;
3804	pImage->state = ISCSISTATE_FREE;
3805	pImage->pvRecvPDUBuf = RTMemAlloc(ISCSI_RECV_PDU_BUFFER_SIZE);
3806	pImage->cbRecvPDUBuf = ISCSI_RECV_PDU_BUFFER_SIZE;
3807	if (pImage->pvRecvPDUBuf == NULL)
3808	{
3809	rc = VERR_NO_MEMORY;
3810	goto out;
3811	}
3812	pImage->Mutex = NIL_RTSEMMUTEX;
3813	pImage->MutexReqQueue = NIL_RTSEMMUTEX;
3814	rc = RTSemMutexCreate(&pImage->Mutex);
3815	if (RT_FAILURE(rc))
3816	goto out;
3817
3818	rc = RTSemMutexCreate(&pImage->MutexReqQueue);
3819	if (RT_FAILURE(rc))
3820	goto out;
3821
3822	/* Validate configuration, detect unknown keys. */
3823	if (!VDCFGAreKeysValid(pImage->pIfConfig,
3824	"TargetName\0"
3825	"InitiatorName\0"
3826	"LUN\0"
3827	"TargetAddress\0"
3828	"InitiatorUsername\0"
3829	"InitiatorSecret\0"
3830	"InitiatorSecretEncrypted\0"
3831	"TargetUsername\0"
3832	"TargetSecret\0"
3833	"WriteSplit\0"
3834	"Timeout\0"
3835	"HostIPStack\0"))
3836	{
3837	rc = vdIfError(pImage->pIfError, VERR_VD_ISCSI_UNKNOWN_CFG_VALUES, RT_SRC_POS, N_("iSCSI: configuration error: unknown configuration keys present"));
3838	goto out;
3839	}
3840
3841	/* Query the iSCSI upper level configuration. */
3842	rc = VDCFGQueryStringAlloc(pImage->pIfConfig,
3843	"TargetName", &pImage->pszTargetName);
3844	if (RT_FAILURE(rc))
3845	{
3846	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("iSCSI: configuration error: failed to read TargetName as string"));
3847	goto out;
3848	}
3849	rc = VDCFGQueryStringAlloc(pImage->pIfConfig,
3850	"InitiatorName", &pImage->pszInitiatorName);
3851	if (rc == VERR_CFGM_VALUE_NOT_FOUND \|\| rc == VERR_CFGM_NO_PARENT)
3852	{
3853	pImage->fAutomaticInitiatorName = true;
3854	rc = VINF_SUCCESS;
3855	}
3856	if (RT_FAILURE(rc))
3857	{
3858	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("iSCSI: configuration error: failed to read InitiatorName as string"));
3859	goto out;
3860	}
3861	rc = VDCFGQueryStringAllocDef(pImage->pIfConfig,
3862	"LUN", &pszLUN, s_iscsiConfigDefaultLUN);
3863	if (RT_FAILURE(rc))
3864	{
3865	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("iSCSI: configuration error: failed to read LUN as string"));
3866	goto out;
3867	}
3868	pszLUNInitial = pszLUN;
3869	if (!strncmp(pszLUN, "enc", 3))
3870	{
3871	fLunEncoded = true;
3872	pszLUN += 3;
3873	}
3874	rc = RTStrToUInt64Full(pszLUN, 0, &pImage->LUN);
3875	if (RT_FAILURE(rc))
3876	{
3877	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("iSCSI: configuration error: failed to convert LUN to integer"));
3878	goto out;
3879	}
3880	if (!fLunEncoded)
3881	{
3882	if (pImage->LUN <= 255)
3883	{
3884	pImage->LUN = pImage->LUN << 48; /* uses peripheral device addressing method */
3885	}
3886	else if (pImage->LUN <= 16383)
3887	{
3888	pImage->LUN = (pImage->LUN << 48) \| RT_BIT_64(62); /* uses flat space addressing method */
3889	}
3890	else
3891	{
3892	rc = VERR_OUT_OF_RANGE;
3893	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("iSCSI: configuration error: LUN number out of range (0-16383)"));
3894	goto out;
3895	}
3896	}
3897	rc = VDCFGQueryStringAlloc(pImage->pIfConfig,
3898	"TargetAddress", &pImage->pszTargetAddress);
3899	if (RT_FAILURE(rc))
3900	{
3901	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("iSCSI: configuration error: failed to read TargetAddress as string"));
3902	goto out;
3903	}
3904	pImage->pszInitiatorUsername = NULL;
3905	rc = VDCFGQueryStringAlloc(pImage->pIfConfig,
3906	"InitiatorUsername",
3907	&pImage->pszInitiatorUsername);
3908	if (rc == VERR_CFGM_VALUE_NOT_FOUND \|\| rc == VERR_CFGM_NO_PARENT)
3909	rc = VINF_SUCCESS;
3910	if (RT_FAILURE(rc))
3911	{
3912	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("iSCSI: configuration error: failed to read InitiatorUsername as string"));
3913	goto out;
3914	}
3915	pImage->pbInitiatorSecret = NULL;
3916	pImage->cbInitiatorSecret = 0;
3917	rc = VDCFGQueryBytesAlloc(pImage->pIfConfig,
3918	"InitiatorSecret",
3919	(void **)&pImage->pbInitiatorSecret,
3920	&pImage->cbInitiatorSecret);
3921	if (rc == VERR_CFGM_VALUE_NOT_FOUND \|\| rc == VERR_CFGM_NO_PARENT)
3922	rc = VINF_SUCCESS;
3923	if (RT_FAILURE(rc))
3924	{
3925	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("iSCSI: configuration error: failed to read InitiatorSecret as byte string"));
3926	goto out;
3927	}
3928	void *pvInitiatorSecretEncrypted;
3929	size_t cbInitiatorSecretEncrypted;
3930	rc = VDCFGQueryBytesAlloc(pImage->pIfConfig,
3931	"InitiatorSecretEncrypted",
3932	&pvInitiatorSecretEncrypted,
3933	&cbInitiatorSecretEncrypted);
3934	if (RT_SUCCESS(rc))
3935	{
3936	RTMemFree(pvInitiatorSecretEncrypted);
3937	if (!pImage->pbInitiatorSecret)
3938	{
3939	/* we have an encrypted initiator secret but not an unencrypted one */
3940	rc = vdIfError(pImage->pIfError, VERR_VD_ISCSI_SECRET_ENCRYPTED, RT_SRC_POS, N_("iSCSI: initiator secret not decrypted"));
3941	goto out;
3942	}
3943	}
3944	pImage->pszTargetUsername = NULL;
3945	rc = VDCFGQueryStringAlloc(pImage->pIfConfig,
3946	"TargetUsername",
3947	&pImage->pszTargetUsername);
3948	if (rc == VERR_CFGM_VALUE_NOT_FOUND \|\| rc == VERR_CFGM_NO_PARENT)
3949	rc = VINF_SUCCESS;
3950	if (RT_FAILURE(rc))
3951	{
3952	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("iSCSI: configuration error: failed to read TargetUsername as string"));
3953	goto out;
3954	}
3955	pImage->pbTargetSecret = NULL;
3956	pImage->cbTargetSecret = 0;
3957	rc = VDCFGQueryBytesAlloc(pImage->pIfConfig,
3958	"TargetSecret", (void **)&pImage->pbTargetSecret,
3959	&pImage->cbTargetSecret);
3960	if (rc == VERR_CFGM_VALUE_NOT_FOUND \|\| rc == VERR_CFGM_NO_PARENT)
3961	rc = VINF_SUCCESS;
3962	if (RT_FAILURE(rc))
3963	{
3964	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("iSCSI: configuration error: failed to read TargetSecret as byte string"));
3965	goto out;
3966	}
3967	rc = VDCFGQueryU32Def(pImage->pIfConfig,
3968	"WriteSplit", &pImage->cbWriteSplit,
3969	uWriteSplitDef);
3970	if (RT_FAILURE(rc))
3971	{
3972	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("iSCSI: configuration error: failed to read WriteSplit as U32"));
3973	goto out;
3974	}
3975
3976	pImage->pszHostname = NULL;
3977	pImage->uPort = 0;
3978	pImage->Socket = NIL_VDSOCKET;
3979	/* Query the iSCSI lower level configuration. */
3980	rc = VDCFGQueryU32Def(pImage->pIfConfig,
3981	"Timeout", &pImage->uReadTimeout,
3982	uTimeoutDef);
3983	if (RT_FAILURE(rc))
3984	{
3985	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("iSCSI: configuration error: failed to read Timeout as U32"));
3986	goto out;
3987	}
3988	rc = VDCFGQueryBoolDef(pImage->pIfConfig,
3989	"HostIPStack", &pImage->fHostIP,
3990	fHostIPDef);
3991	if (RT_FAILURE(rc))
3992	{
3993	rc = vdIfError(pImage->pIfError, rc, RT_SRC_POS, N_("iSCSI: configuration error: failed to read HostIPStack as boolean"));
3994	goto out;
3995	}
3996
3997	/* Don't actually establish iSCSI transport connection if this is just an
3998	* open to query the image information and the host IP stack isn't used.
3999	* Even trying is rather useless, as in this context the InTnet IP stack
4000	* isn't present. Returning dummies is the best possible result anyway. */
4001	if ((uOpenFlags & VD_OPEN_FLAGS_INFO) && !pImage->fHostIP)
4002	{
4003	LogFunc(("Not opening the transport connection as IntNet IP stack is not available. Will return dummies\n"));
4004	goto out;
4005	}
4006
4007	memset(pImage->aCmdsWaiting, 0, sizeof(pImage->aCmdsWaiting));
4008	pImage->cbRecvPDUResidual = 0;
4009
4010	/* Create the socket structure. */
4011	rc = pImage->pIfNet->pfnSocketCreate(VD_INTERFACETCPNET_CONNECT_EXTENDED_SELECT,
4012	&pImage->Socket);
4013	if (RT_SUCCESS(rc))
4014	{
4015	pImage->fExtendedSelectSupported = true;
4016	pImage->fRunning = true;
4017	rc = RTThreadCreate(&pImage->hThreadIo, iscsiIoThreadWorker, pImage, 0,
4018	RTTHREADTYPE_IO, RTTHREADFLAGS_WAITABLE, "iSCSI-Io");
4019	if (RT_FAILURE(rc))
4020	{
4021	LogFunc(("Creating iSCSI I/O thread failed rc=%Rrc\n", rc));
4022	goto out;
4023	}
4024	}
4025	else if (rc == VERR_NOT_SUPPORTED)
4026	{
4027	/* Async I/O is not supported without extended select. */
4028	if ((uOpenFlags & VD_OPEN_FLAGS_ASYNC_IO))
4029	{
4030	LogFunc(("Extended select is not supported by the interface but async I/O is requested -> %Rrc\n", rc));
4031	goto out;
4032	}
4033	else
4034	{
4035	pImage->fExtendedSelectSupported = false;
4036	rc = pImage->pIfNet->pfnSocketCreate(0, &pImage->Socket);
4037	if (RT_FAILURE(rc))
4038	{
4039	LogFunc(("Creating socket failed -> %Rrc\n", rc));
4040	goto out;
4041	}
4042	}
4043	}
4044	else
4045	{
4046	LogFunc(("Creating socket failed -> %Rrc\n", rc));
4047	goto out;
4048	}
4049
4050	/*
4051	* Attach to the iSCSI target. This implicitly establishes the iSCSI
4052	* transport connection.
4053	*/
4054	rc = iscsiExecSync(pImage, iscsiAttach, pImage);
4055	if (RT_FAILURE(rc))
4056	{
4057	LogRel(("iSCSI: could not open target %s, rc=%Rrc\n", pImage->pszTargetName, rc));
4058	goto out;
4059	}
4060	LogFlowFunc(("target '%s' opened successfully\n", pImage->pszTargetName));
4061
4062	SCSIREQ sr;
4063	RTSGSEG DataSeg;
4064	uint8_t sense[96];
4065	uint8_t data8[8];
4066	uint8_t data12[12];
4067
4068	/*
4069	* Inquire available LUNs - purely dummy request.
4070	*/
4071	uint8_t CDB_rlun[12];
4072	uint8_t rlundata[16];
4073	CDB_rlun[0] = SCSI_REPORT_LUNS;
4074	CDB_rlun[1] = 0; /* reserved */
4075	CDB_rlun[2] = 0; /* reserved */
4076	CDB_rlun[3] = 0; /* reserved */
4077	CDB_rlun[4] = 0; /* reserved */
4078	CDB_rlun[5] = 0; /* reserved */
4079	CDB_rlun[6] = sizeof(rlundata) >> 24;
4080	CDB_rlun[7] = (sizeof(rlundata) >> 16) & 0xff;
4081	CDB_rlun[8] = (sizeof(rlundata) >> 8) & 0xff;
4082	CDB_rlun[9] = sizeof(rlundata) & 0xff;
4083	CDB_rlun[10] = 0; /* reserved */
4084	CDB_rlun[11] = 0; /* control */
4085
4086	DataSeg.pvSeg = rlundata;
4087	DataSeg.cbSeg = sizeof(rlundata);
4088
4089	sr.enmXfer = SCSIXFER_FROM_TARGET;
4090	sr.cbCDB = sizeof(CDB_rlun);
4091	sr.pvCDB = CDB_rlun;
4092	sr.cbI2TData = 0;
4093	sr.paI2TSegs = NULL;
4094	sr.cI2TSegs = 0;
4095	sr.cbT2IData = DataSeg.cbSeg;
4096	sr.paT2ISegs = &DataSeg;
4097	sr.cT2ISegs = 1;
4098	sr.cbSense = sizeof(sense);
4099	sr.pvSense = sense;
4100
4101	rc = iscsiCommandSync(pImage, &sr, false, VERR_INVALID_STATE);
4102	if (RT_FAILURE(rc))
4103	{
4104	LogRel(("iSCSI: Could not get LUN info for target %s, rc=%Rrc\n", pImage->pszTargetName, rc));
4105	return rc;
4106	}
4107
4108	/*
4109	* Inquire device characteristics - no tapes, scanners etc., please.
4110	*/
4111	uint8_t CDB_inq[6];
4112	CDB_inq[0] = SCSI_INQUIRY;
4113	CDB_inq[1] = 0; /* reserved */
4114	CDB_inq[2] = 0; /* reserved */
4115	CDB_inq[3] = 0; /* reserved */
4116	CDB_inq[4] = sizeof(data8);
4117	CDB_inq[5] = 0; /* control */
4118
4119	DataSeg.pvSeg = data8;
4120	DataSeg.cbSeg = sizeof(data8);
4121
4122	sr.enmXfer = SCSIXFER_FROM_TARGET;
4123	sr.cbCDB = sizeof(CDB_inq);
4124	sr.pvCDB = CDB_inq;
4125	sr.cbI2TData = 0;
4126	sr.paI2TSegs = NULL;
4127	sr.cI2TSegs = 0;
4128	sr.cbT2IData = DataSeg.cbSeg;
4129	sr.paT2ISegs = &DataSeg;
4130	sr.cT2ISegs = 1;
4131	sr.cbSense = sizeof(sense);
4132	sr.pvSense = sense;
4133
4134	rc = iscsiCommandSync(pImage, &sr, true /* fRetry */, VERR_INVALID_STATE);
4135	if (RT_SUCCESS(rc))
4136	{
4137	uint8_t devType = (sr.cbT2IData > 0) ? data8[0] & SCSI_DEVTYPE_MASK : 255;
4138	if (devType != SCSI_DEVTYPE_DISK)
4139	{
4140	rc = vdIfError(pImage->pIfError, VERR_VD_ISCSI_INVALID_TYPE,
4141	RT_SRC_POS, N_("iSCSI: target address %s, target name %s, SCSI LUN %lld reports device type=%u"),
4142	pImage->pszTargetAddress, pImage->pszTargetName,
4143	pImage->LUN, devType);
4144	LogRel(("iSCSI: Unsupported SCSI peripheral device type %d for target %s\n", devType & SCSI_DEVTYPE_MASK, pImage->pszTargetName));
4145	goto out;
4146	}
4147	uint8_t uCmdQueue = (sr.cbT2IData >= 8) ? data8[7] & SCSI_INQUIRY_CMDQUE_MASK : 0;
4148	if (uCmdQueue > 0)
4149	pImage->fCmdQueuingSupported = true;
4150	else if (uOpenFlags & VD_OPEN_FLAGS_ASYNC_IO)
4151	{
4152	rc = VERR_NOT_SUPPORTED;
4153	goto out;
4154	}
4155
4156	LogRel(("iSCSI: target address %s, target name %s, %s command queuing\n",
4157	pImage->pszTargetAddress, pImage->pszTargetName,
4158	pImage->fCmdQueuingSupported ? "supports" : "doesn't support"));
4159	}
4160	else
4161	{
4162	LogRel(("iSCSI: Could not get INQUIRY info for target %s, rc=%Rrc\n", pImage->pszTargetName, rc));
4163	goto out;
4164	}
4165
4166	/*
4167	* Query write disable bit in the device specific parameter entry in the
4168	* mode parameter header. Refuse read/write opening of read only disks.
4169	*/
4170
4171	uint8_t CDB_ms[6];
4172	uint8_t data4[4];
4173	CDB_ms[0] = SCSI_MODE_SENSE_6;
4174	CDB_ms[1] = 0; /* dbd=0/reserved */
4175	CDB_ms[2] = 0x3f; /* pc=0/page code=0x3f, ask for all pages */
4176	CDB_ms[3] = 0; /* subpage code=0, return everything in page_0 format */
4177	CDB_ms[4] = sizeof(data4); /* allocation length=4 */
4178	CDB_ms[5] = 0; /* control */
4179
4180	DataSeg.pvSeg = data4;
4181	DataSeg.cbSeg = sizeof(data4);
4182
4183	sr.enmXfer = SCSIXFER_FROM_TARGET;
4184	sr.cbCDB = sizeof(CDB_ms);
4185	sr.pvCDB = CDB_ms;
4186	sr.cbI2TData = 0;
4187	sr.paI2TSegs = NULL;
4188	sr.cI2TSegs = 0;
4189	sr.cbT2IData = DataSeg.cbSeg;
4190	sr.paT2ISegs = &DataSeg;
4191	sr.cT2ISegs = 1;
4192	sr.cbSense = sizeof(sense);
4193	sr.pvSense = sense;
4194
4195	rc = iscsiCommandSync(pImage, &sr, true /* fRetry */, VERR_INVALID_STATE);
4196	if (RT_SUCCESS(rc))
4197	{
4198	if (!(uOpenFlags & VD_OPEN_FLAGS_READONLY) && data4[2] & 0x80)
4199	{
4200	rc = VERR_VD_IMAGE_READ_ONLY;
4201	goto out;
4202	}
4203	}
4204	else
4205	{
4206	LogRel(("iSCSI: Could not get MODE SENSE info for target %s, rc=%Rrc\n", pImage->pszTargetName, rc));
4207	goto out;
4208	}
4209
4210	/*
4211	* Determine sector size and capacity of the volume immediately.
4212	*/
4213	uint8_t CDB_cap[16];
4214
4215	RT_ZERO(data12);
4216	RT_ZERO(CDB_cap);
4217	CDB_cap[0] = SCSI_SERVICE_ACTION_IN_16;
4218	CDB_cap[1] = SCSI_SVC_ACTION_IN_READ_CAPACITY_16; /* subcommand */
4219	CDB_cap[10+3] = sizeof(data12); /* allocation length (dword) */
4220
4221	DataSeg.pvSeg = data12;
4222	DataSeg.cbSeg = sizeof(data12);
4223
4224	sr.enmXfer = SCSIXFER_FROM_TARGET;
4225	sr.cbCDB = sizeof(CDB_cap);
4226	sr.pvCDB = CDB_cap;
4227	sr.cbI2TData = 0;
4228	sr.paI2TSegs = NULL;
4229	sr.cI2TSegs = 0;
4230	sr.cbT2IData = DataSeg.cbSeg;
4231	sr.paT2ISegs = &DataSeg;
4232	sr.cT2ISegs = 1;
4233	sr.cbSense = sizeof(sense);
4234	sr.pvSense = sense;
4235
4236	rc = iscsiCommandSync(pImage, &sr, false /* fRetry */, VINF_SUCCESS);
4237	if (RT_SUCCESS(rc))
4238	{
4239	bool b_end = false;
4240	uint8_t max_counter = 10;
4241	do
4242	{
4243	switch (sr.status)
4244	{
4245	case SCSI_STATUS_OK:
4246	{
4247	pImage->cVolume = RT_BE2H_U64((uint64_t )&data12[0]);
4248	pImage->cVolume++;
4249	pImage->cbSector = RT_BE2H_U32((uint32_t )&data12[8]);
4250	pImage->cbSize = pImage->cVolume * pImage->cbSector;
4251	if (pImage->cVolume == 0 \|\| pImage->cbSector != 512 \|\| pImage->cbSize < pImage->cVolume)
4252	{
4253	rc = vdIfError(pImage->pIfError, VERR_VD_ISCSI_INVALID_TYPE,
4254	RT_SRC_POS, N_("iSCSI: target address %s, target name %s, SCSI LUN %lld reports media sector count=%llu sector size=%u"),
4255	pImage->pszTargetAddress, pImage->pszTargetName,
4256	pImage->LUN, pImage->cVolume, pImage->cbSector);
4257	}
4258	b_end = true;
4259	break;
4260	}
4261	case SCSI_STATUS_CHECK_CONDITION:
4262	{
4263	if((sense[2]&0x0F)==SCSI_SENSE_UNIT_ATTENTION)
4264	{
4265	if(sense[12]==SCSI_ASC_POWER_ON_RESET_BUS_DEVICE_RESET_OCCURRED &&
4266	sense[13]==SCSI_ASCQ_POWER_ON_RESET_BUS_DEVICE_RESET_OCCURRED)
4267	{
4268	/** @todo for future: prepare and send command "REQUEST SENSE" which will
4269	return the status of target and will clear any unit attention condition that it reports */
4270	rc = iscsiCommandSync(pImage, &sr, false /* fRetry */, VINF_SUCCESS);
4271	if (RT_FAILURE(rc))
4272	b_end = true;
4273	--max_counter;
4274	break;
4275
4276	}
4277	}
4278	break;
4279	}
4280	default:
4281	{
4282	rc = iscsiCommandSync(pImage, &sr, false /* fRetry */, VINF_SUCCESS);
4283	if (RT_FAILURE(rc))
4284	b_end = true;
4285	--max_counter;
4286	break;
4287	}
4288	}
4289	if (max_counter==0)
4290	b_end=true;
4291	}while(!b_end);
4292	}
4293	else
4294	{
4295	uint8_t CDB_capfb[10];
4296
4297	RT_ZERO(data8);
4298	CDB_capfb[0] = SCSI_READ_CAPACITY;
4299	CDB_capfb[1] = 0; /* reserved */
4300	CDB_capfb[2] = 0; /* reserved */
4301	CDB_capfb[3] = 0; /* reserved */
4302	CDB_capfb[4] = 0; /* reserved */
4303	CDB_capfb[5] = 0; /* reserved */
4304	CDB_capfb[6] = 0; /* reserved */
4305	CDB_capfb[7] = 0; /* reserved */
4306	CDB_capfb[8] = 0; /* reserved */
4307	CDB_capfb[9] = 0; /* control */
4308
4309	DataSeg.pvSeg = data8;
4310	DataSeg.cbSeg = sizeof(data8);
4311
4312	sr.enmXfer = SCSIXFER_FROM_TARGET;
4313	sr.cbCDB = sizeof(CDB_capfb);
4314	sr.pvCDB = CDB_capfb;
4315	sr.cbI2TData = 0;
4316	sr.paI2TSegs = NULL;
4317	sr.cI2TSegs = 0;
4318	sr.cbT2IData = DataSeg.cbSeg;
4319	sr.paT2ISegs = &DataSeg;
4320	sr.cT2ISegs = 1;
4321	sr.cbSense = sizeof(sense);
4322	sr.pvSense = sense;
4323
4324	rc = iscsiCommandSync(pImage, &sr, false /* fRetry */, VINF_SUCCESS);
4325	if (RT_SUCCESS(rc))
4326	{
4327	bool b_end = false;
4328	uint8_t max_counter = 10;
4329	do
4330	{
4331	switch (sr.status)
4332	{
4333	case SCSI_STATUS_OK:
4334	{
4335	pImage->cVolume = (data8[0] << 24) \| (data8[1] << 16) \| (data8[2] << 8) \| data8[3];
4336	pImage->cVolume++;
4337	pImage->cbSector = (data8[4] << 24) \| (data8[5] << 16) \| (data8[6] << 8) \| data8[7];
4338	pImage->cbSize = pImage->cVolume * pImage->cbSector;
4339	if (pImage->cVolume == 0 \|\| pImage->cbSector != 512)
4340	{
4341	rc = vdIfError(pImage->pIfError, VERR_VD_ISCSI_INVALID_TYPE,
4342	RT_SRC_POS, N_("iSCSI: fallback capacity detectio for target address %s, target name %s, SCSI LUN %lld reports media sector count=%llu sector size=%u"),
4343	pImage->pszTargetAddress, pImage->pszTargetName,
4344	pImage->LUN, pImage->cVolume, pImage->cbSector);
4345	}
4346
4347	b_end = true;
4348	break;
4349	}
4350	case SCSI_STATUS_CHECK_CONDITION:
4351	{
4352	if((sense[2]&0x0F)==SCSI_SENSE_UNIT_ATTENTION)
4353	{
4354	if(sense[12]==SCSI_ASC_POWER_ON_RESET_BUS_DEVICE_RESET_OCCURRED &&
4355	sense[13]==SCSI_ASCQ_POWER_ON_RESET_BUS_DEVICE_RESET_OCCURRED)
4356	{
4357	/** @todo for future: prepare and send command "REQUEST SENSE" which will
4358	return the status of target and will clear any unit attention condition that it reports */
4359	rc = iscsiCommandSync(pImage, &sr, false /* fRetry */, VINF_SUCCESS);
4360	if (RT_FAILURE(rc))
4361	b_end = true;
4362	--max_counter;
4363	break;
4364
4365	}
4366	}
4367	break;
4368	}
4369	default:
4370	{
4371	rc = iscsiCommandSync(pImage, &sr, false /* fRetry */, VINF_SUCCESS);
4372	if (RT_FAILURE(rc))
4373	b_end = true;
4374	--max_counter;
4375	break;
4376	}
4377	}
4378	if (max_counter==0)
4379	b_end=true;
4380	}while(!b_end);
4381	}
4382	else
4383	{
4384	LogRel(("iSCSI: Could not determine capacity of target %s, rc=%Rrc\n", pImage->pszTargetName, rc));
4385	goto out;
4386	}
4387	}
4388
4389	/*
4390	* Check the read and write cache bits.
4391	* Try to enable the cache if it is disabled.
4392	*
4393	* We already checked that this is a block access device. No need
4394	* to do it again.
4395	*/
4396	uint8_t aCachingModePage[32];
4397	uint8_t aCDBModeSense6[6];
4398
4399	memset(aCachingModePage, '\0', sizeof(aCachingModePage));
4400	aCDBModeSense6[0] = SCSI_MODE_SENSE_6;
4401	aCDBModeSense6[1] = 0;
4402	aCDBModeSense6[2] = (0x00 << 6) \| (0x08 & 0x3f); /* Current values and caching mode page */
4403	aCDBModeSense6[3] = 0; /* Sub page code. */
4404	aCDBModeSense6[4] = sizeof(aCachingModePage) & 0xff;
4405	aCDBModeSense6[5] = 0;
4406
4407	DataSeg.pvSeg = aCachingModePage;
4408	DataSeg.cbSeg = sizeof(aCachingModePage);
4409
4410	sr.enmXfer = SCSIXFER_FROM_TARGET;
4411	sr.cbCDB = sizeof(aCDBModeSense6);
4412	sr.pvCDB = aCDBModeSense6;
4413	sr.cbI2TData = 0;
4414	sr.paI2TSegs = NULL;
4415	sr.cI2TSegs = 0;
4416	sr.cbT2IData = DataSeg.cbSeg;
4417	sr.paT2ISegs = &DataSeg;
4418	sr.cT2ISegs = 1;
4419	sr.cbSense = sizeof(sense);
4420	sr.pvSense = sense;
4421	rc = iscsiCommandSync(pImage, &sr, false /* fRetry */, VINF_SUCCESS);
4422	if ( RT_SUCCESS(rc)
4423	&& (sr.status == SCSI_STATUS_OK)
4424	&& (aCachingModePage[0] >= 15)
4425	&& (aCachingModePage[4 + aCachingModePage[3]] & 0x3f) == 0x08
4426	&& (aCachingModePage[4 + aCachingModePage[3] + 1] > 3))
4427	{
4428	uint32_t Offset = 4 + aCachingModePage[3];
4429	/*
4430	* Check if the read and/or the write cache is disabled.
4431	* The write cache is disabled if bit 2 (WCE) is zero and
4432	* the read cache is disabled if bit 0 (RCD) is set.
4433	*/
4434	if (!ASMBitTest(&aCachingModePage[Offset + 2], 2) \|\| ASMBitTest(&aCachingModePage[Offset + 2], 0))
4435	{
4436	/*
4437	* Write Cache Enable (WCE) bit is zero or the Read Cache Disable (RCD) is one
4438	* So one of the caches is disabled. Enable both caches.
4439	* The rest is unchanged.
4440	*/
4441	ASMBitSet(&aCachingModePage[Offset + 2], 2);
4442	ASMBitClear(&aCachingModePage[Offset + 2], 0);
4443
4444	uint8_t aCDBCaching[6];
4445	aCDBCaching[0] = SCSI_MODE_SELECT_6;
4446	aCDBCaching[1] = 0; /* Don't write the page into NV RAM. */
4447	aCDBCaching[2] = 0;
4448	aCDBCaching[3] = 0;
4449	aCDBCaching[4] = sizeof(aCachingModePage) & 0xff;
4450	aCDBCaching[5] = 0;
4451
4452	DataSeg.pvSeg = aCachingModePage;
4453	DataSeg.cbSeg = sizeof(aCachingModePage);
4454
4455	sr.enmXfer = SCSIXFER_TO_TARGET;
4456	sr.cbCDB = sizeof(aCDBCaching);
4457	sr.pvCDB = aCDBCaching;
4458	sr.cbI2TData = DataSeg.cbSeg;
4459	sr.paI2TSegs = &DataSeg;
4460	sr.cI2TSegs = 1;
4461	sr.cbT2IData = 0;
4462	sr.paT2ISegs = NULL;
4463	sr.cT2ISegs = 0;
4464	sr.cbSense = sizeof(sense);
4465	sr.pvSense = sense;
4466	sr.status = 0;
4467	rc = iscsiCommandSync(pImage, &sr, false /* fRetry */, VINF_SUCCESS);
4468	if ( RT_SUCCESS(rc)
4469	&& (sr.status == SCSI_STATUS_OK))
4470	{
4471	LogRel(("iSCSI: Enabled read and write cache of target %s\n", pImage->pszTargetName));
4472	}
4473	else
4474	{
4475	/* Log failures but continue. */
4476	LogRel(("iSCSI: Could not enable read and write cache of target %s, rc=%Rrc status=%#x\n",
4477	pImage->pszTargetName, rc, sr.status));
4478	LogRel(("iSCSI: Sense:\n%.*Rhxd\n", sr.cbSense, sense));
4479	rc = VINF_SUCCESS;
4480	}
4481	}
4482	}
4483	else
4484	{
4485	/* Log errors but continue. */
4486	LogRel(("iSCSI: Could not check write cache of target %s, rc=%Rrc, got mode page %#x\n", pImage->pszTargetName, rc,aCachingModePage[0] & 0x3f));
4487	LogRel(("iSCSI: Sense:\n%.*Rhxd\n", sr.cbSense, sense));
4488	rc = VINF_SUCCESS;
4489	}
4490
4491	out:
4492	if (RT_FAILURE(rc))
4493	iscsiFreeImage(pImage, false);
4494	return rc;
4495	}
4496
4497
4498	/** @copydoc VBOXHDDBACKEND::pfnCheckIfValid */
4499	static int iscsiCheckIfValid(const char *pszFilename, PVDINTERFACE pVDIfsDisk,
4500	PVDINTERFACE pVDIfsImage, VDTYPE *penmType)
4501	{
4502	LogFlowFunc(("pszFilename=\"%s\"\n", pszFilename));
4503
4504	/* iSCSI images can't be checked for validity this way, as the filename
4505	* just can't supply enough configuration information. */
4506	int rc = VERR_VD_ISCSI_INVALID_HEADER;
4507
4508	LogFlowFunc(("returns %Rrc\n", rc));
4509	return rc;
4510	}
4511
4512	/** @copydoc VBOXHDDBACKEND::pfnOpen */
4513	static int iscsiOpen(const char *pszFilename, unsigned uOpenFlags,
4514	PVDINTERFACE pVDIfsDisk, PVDINTERFACE pVDIfsImage,
4515	VDTYPE enmType, void **ppBackendData)
4516	{
4517	LogFlowFunc(("pszFilename=\"%s\" uOpenFlags=%#x pVDIfsDisk=%#p pVDIfsImage=%#p ppBackendData=%#p\n", pszFilename, uOpenFlags, pVDIfsDisk, pVDIfsImage, ppBackendData));
4518	int rc;
4519	PISCSIIMAGE pImage;
4520
4521	/* Check open flags. All valid flags are supported. */
4522	if (uOpenFlags & ~VD_OPEN_FLAGS_MASK)
4523	{
4524	rc = VERR_INVALID_PARAMETER;
4525	goto out;
4526	}
4527
4528	/* Check remaining arguments. */
4529	if ( !VALID_PTR(pszFilename)
4530	\|\| !*pszFilename
4531	\|\| strchr(pszFilename, '"'))
4532	{
4533	rc = VERR_INVALID_PARAMETER;
4534	goto out;
4535	}
4536
4537	pImage = (PISCSIIMAGE)RTMemAllocZ(sizeof(ISCSIIMAGE));
4538	if (!pImage)
4539	{
4540	rc = VERR_NO_MEMORY;
4541	goto out;
4542	}
4543
4544	pImage->pszFilename = pszFilename;
4545	pImage->pszInitiatorName = NULL;
4546	pImage->pszTargetName = NULL;
4547	pImage->pszTargetAddress = NULL;
4548	pImage->pszInitiatorUsername = NULL;
4549	pImage->pbInitiatorSecret = NULL;
4550	pImage->pszTargetUsername = NULL;
4551	pImage->pbTargetSecret = NULL;
4552	pImage->paCurrReq = NULL;
4553	pImage->pvRecvPDUBuf = NULL;
4554	pImage->pszHostname = NULL;
4555	pImage->pVDIfsDisk = pVDIfsDisk;
4556	pImage->pVDIfsImage = pVDIfsImage;
4557	pImage->cLogRelErrors = 0;
4558
4559	rc = iscsiOpenImage(pImage, uOpenFlags);
4560	if (RT_SUCCESS(rc))
4561	{
4562	LogFlowFunc(("target %s cVolume %d, cbSector %d\n", pImage->pszTargetName, pImage->cVolume, pImage->cbSector));
4563	LogRel(("iSCSI: target address %s, target name %s, SCSI LUN %lld\n", pImage->pszTargetAddress, pImage->pszTargetName, pImage->LUN));
4564	*ppBackendData = pImage;
4565	}
4566	else
4567	RTMemFree(pImage);
4568
4569	out:
4570	LogFlowFunc(("returns %Rrc (pBackendData=%#p)\n", rc, *ppBackendData));
4571	return rc;
4572	}
4573
4574	/** @copydoc VBOXHDDBACKEND::pfnCreate */
4575	static int iscsiCreate(const char *pszFilename, uint64_t cbSize,
4576	unsigned uImageFlags, const char *pszComment,
4577	PCVDGEOMETRY pPCHSGeometry, PCVDGEOMETRY pLCHSGeometry,
4578	PCRTUUID pUuid, unsigned uOpenFlags,
4579	unsigned uPercentStart, unsigned uPercentSpan,
4580	PVDINTERFACE pVDIfsDisk, PVDINTERFACE pVDIfsImage,
4581	PVDINTERFACE pVDIfsOperation, void **ppBackendData)
4582	{
4583	LogFlowFunc(("pszFilename=\"%s\" cbSize=%llu uImageFlags=%#x pszComment=\"%s\" pPCHSGeometry=%#p pLCHSGeometry=%#p Uuid=%RTuuid uOpenFlags=%#x uPercentStart=%u uPercentSpan=%u pVDIfsDisk=%#p pVDIfsImage=%#p pVDIfsOperation=%#p ppBackendData=%#p", pszFilename, cbSize, uImageFlags, pszComment, pPCHSGeometry, pLCHSGeometry, pUuid, uOpenFlags, uPercentStart, uPercentSpan, pVDIfsDisk, pVDIfsImage, pVDIfsOperation, ppBackendData));
4584	int rc = VERR_NOT_SUPPORTED;
4585
4586	LogFlowFunc(("returns %Rrc (pBackendData=%#p)\n", rc, *ppBackendData));
4587	return rc;
4588	}
4589
4590	/** @copydoc VBOXHDDBACKEND::pfnClose */
4591	static int iscsiClose(void *pBackendData, bool fDelete)
4592	{
4593	LogFlowFunc(("pBackendData=%#p fDelete=%d\n", pBackendData, fDelete));
4594	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
4595	int rc;
4596
4597	Assert(!fDelete); /* This flag is unsupported. */
4598
4599	rc = iscsiFreeImage(pImage, fDelete);
4600	RTMemFree(pImage);
4601
4602	LogFlowFunc(("returns %Rrc\n", rc));
4603	return rc;
4604	}
4605
4606	/** @copydoc VBOXHDDBACKEND::pfnRead */
4607	static int iscsiRead(void pBackendData, uint64_t uOffset, void pvBuf,
4608	size_t cbToRead, size_t *pcbActuallyRead)
4609	{
4610	/** @todo reinstate logging of the target everywhere - dropped temporarily */
4611	LogFlowFunc(("pBackendData=%#p uOffset=%llu pvBuf=%#p cbToRead=%zu pcbActuallyRead=%#p\n", pBackendData, uOffset, pvBuf, cbToRead, pcbActuallyRead));
4612	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
4613	uint64_t lba;
4614	uint16_t tls;
4615	int rc;
4616
4617	Assert(pImage);
4618	Assert(uOffset % 512 == 0);
4619	Assert(cbToRead % 512 == 0);
4620
4621	Assert(pImage->cbSector);
4622	AssertPtr(pvBuf);
4623
4624	if ( uOffset + cbToRead > pImage->cbSize
4625	\|\| cbToRead == 0)
4626	{
4627	rc = VERR_INVALID_PARAMETER;
4628	goto out;
4629	}
4630
4631	/*
4632	* Clip read size to a value which is supported by the target.
4633	*/
4634	cbToRead = RT_MIN(cbToRead, pImage->cbRecvDataLength);
4635
4636	lba = uOffset / pImage->cbSector;
4637	tls = (uint16_t)(cbToRead / pImage->cbSector);
4638	SCSIREQ sr;
4639	RTSGSEG T2ISeg;
4640	size_t cbCDB;
4641	uint8_t abCDB[16];
4642	uint8_t sense[96];
4643
4644	if (pImage->cVolume < _4G)
4645	{
4646	cbCDB = 10;
4647	abCDB[0] = SCSI_READ_10;
4648	abCDB[1] = 0; /* reserved */
4649	abCDB[2] = (lba >> 24) & 0xff;
4650	abCDB[3] = (lba >> 16) & 0xff;
4651	abCDB[4] = (lba >> 8) & 0xff;
4652	abCDB[5] = lba & 0xff;
4653	abCDB[6] = 0; /* reserved */
4654	abCDB[7] = (tls >> 8) & 0xff;
4655	abCDB[8] = tls & 0xff;
4656	abCDB[9] = 0; /* control */
4657	}
4658	else
4659	{
4660	cbCDB = 16;
4661	abCDB[0] = SCSI_READ_16;
4662	abCDB[1] = 0; /* reserved */
4663	abCDB[2] = (lba >> 56) & 0xff;
4664	abCDB[3] = (lba >> 48) & 0xff;
4665	abCDB[4] = (lba >> 40) & 0xff;
4666	abCDB[5] = (lba >> 32) & 0xff;
4667	abCDB[6] = (lba >> 24) & 0xff;
4668	abCDB[7] = (lba >> 16) & 0xff;
4669	abCDB[8] = (lba >> 8) & 0xff;
4670	abCDB[9] = lba & 0xff;
4671	abCDB[10] = 0; /* tls unused */
4672	abCDB[11] = 0; /* tls unused */
4673	abCDB[12] = (tls >> 8) & 0xff;
4674	abCDB[13] = tls & 0xff;
4675	abCDB[14] = 0; /* reserved */
4676	abCDB[15] = 0; /* reserved */
4677	}
4678
4679	T2ISeg.pvSeg = pvBuf;
4680	T2ISeg.cbSeg = cbToRead;
4681
4682	sr.enmXfer = SCSIXFER_FROM_TARGET;
4683	sr.cbCDB = cbCDB;
4684	sr.pvCDB = abCDB;
4685	sr.cbI2TData = 0;
4686	sr.paI2TSegs = NULL;
4687	sr.cI2TSegs = 0;
4688	sr.cbT2IData = cbToRead;
4689	sr.paT2ISegs = &T2ISeg;
4690	sr.cT2ISegs = 1;
4691	sr.cbSense = sizeof(sense);
4692	sr.pvSense = sense;
4693
4694	rc = iscsiCommandSync(pImage, &sr, true, VERR_READ_ERROR);
4695	if (RT_FAILURE(rc))
4696	{
4697	LogFlow(("iscsiCommandSync(%s, %#llx) -> %Rrc\n", pImage->pszTargetName, uOffset, rc));
4698	*pcbActuallyRead = 0;
4699	}
4700	else
4701	*pcbActuallyRead = sr.cbT2IData;
4702
4703	out:
4704	LogFlowFunc(("returns %Rrc\n", rc));
4705	return rc;
4706	}
4707
4708	/** @copydoc VBOXHDDBACKEND::pfnWrite */
4709	static int iscsiWrite(void pBackendData, uint64_t uOffset, const void pvBuf,
4710	size_t cbToWrite, size_t *pcbWriteProcess,
4711	size_t pcbPreRead, size_t pcbPostRead, unsigned fWrite)
4712	{
4713	LogFlowFunc(("pBackendData=%#p uOffset=%llu pvBuf=%#p cbToWrite=%zu pcbWriteProcess=%#p pcbPreRead=%#p pcbPostRead=%#p\n", pBackendData, uOffset, pvBuf, cbToWrite, pcbWriteProcess, pcbPreRead, pcbPostRead));
4714	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
4715	uint64_t lba;
4716	uint16_t tls;
4717	int rc;
4718
4719	Assert(pImage);
4720	Assert(uOffset % 512 == 0);
4721	Assert(cbToWrite % 512 == 0);
4722
4723	Assert(pImage->cbSector);
4724	Assert(pvBuf);
4725
4726	if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
4727	{
4728	rc = VERR_VD_IMAGE_READ_ONLY;
4729	goto out;
4730	}
4731
4732	*pcbPreRead = 0;
4733	*pcbPostRead = 0;
4734
4735	/*
4736	* Clip write size to a value which is supported by the target.
4737	*/
4738	cbToWrite = RT_MIN(cbToWrite, pImage->cbSendDataLength);
4739
4740	lba = uOffset / pImage->cbSector;
4741	tls = (uint16_t)(cbToWrite / pImage->cbSector);
4742	SCSIREQ sr;
4743	RTSGSEG I2TSeg;
4744	size_t cbCDB;
4745	uint8_t abCDB[16];
4746	uint8_t sense[96];
4747
4748	if (pImage->cVolume < _4G)
4749	{
4750	cbCDB = 10;
4751	abCDB[0] = SCSI_WRITE_10;
4752	abCDB[1] = 0; /* reserved */
4753	abCDB[2] = (lba >> 24) & 0xff;
4754	abCDB[3] = (lba >> 16) & 0xff;
4755	abCDB[4] = (lba >> 8) & 0xff;
4756	abCDB[5] = lba & 0xff;
4757	abCDB[6] = 0; /* reserved */
4758	abCDB[7] = (tls >> 8) & 0xff;
4759	abCDB[8] = tls & 0xff;
4760	abCDB[9] = 0; /* control */
4761	}
4762	else
4763	{
4764	cbCDB = 16;
4765	abCDB[0] = SCSI_WRITE_16;
4766	abCDB[1] = 0; /* reserved */
4767	abCDB[2] = (lba >> 56) & 0xff;
4768	abCDB[3] = (lba >> 48) & 0xff;
4769	abCDB[4] = (lba >> 40) & 0xff;
4770	abCDB[5] = (lba >> 32) & 0xff;
4771	abCDB[6] = (lba >> 24) & 0xff;
4772	abCDB[7] = (lba >> 16) & 0xff;
4773	abCDB[8] = (lba >> 8) & 0xff;
4774	abCDB[9] = lba & 0xff;
4775	abCDB[10] = 0; /* tls unused */
4776	abCDB[11] = 0; /* tls unused */
4777	abCDB[12] = (tls >> 8) & 0xff;
4778	abCDB[13] = tls & 0xff;
4779	abCDB[14] = 0; /* reserved */
4780	abCDB[15] = 0; /* reserved */
4781	}
4782
4783	I2TSeg.pvSeg = (void *)pvBuf;
4784	I2TSeg.cbSeg = cbToWrite;
4785
4786	sr.enmXfer = SCSIXFER_TO_TARGET;
4787	sr.cbCDB = cbCDB;
4788	sr.pvCDB = abCDB;
4789	sr.cbI2TData = cbToWrite;
4790	sr.paI2TSegs = &I2TSeg;
4791	sr.cI2TSegs = 1;
4792	sr.cbT2IData = 0;
4793	sr.paT2ISegs = NULL;
4794	sr.cT2ISegs = 0;
4795	sr.cbSense = sizeof(sense);
4796	sr.pvSense = sense;
4797
4798	rc = iscsiCommandSync(pImage, &sr, true, VERR_WRITE_ERROR);
4799	if (RT_FAILURE(rc))
4800	{
4801	LogFlow(("iscsiCommandSync(%s, %#llx) -> %Rrc\n", pImage->pszTargetName, uOffset, rc));
4802	*pcbWriteProcess = 0;
4803	}
4804	else
4805	*pcbWriteProcess = cbToWrite;
4806
4807	out:
4808	LogFlowFunc(("returns %Rrc\n", rc));
4809	return rc;
4810	}
4811
4812	/** @copydoc VBOXHDDBACKEND::pfnFlush */
4813	static int iscsiFlush(void *pBackendData)
4814	{
4815	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
4816	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
4817	int rc;
4818
4819	Assert(pImage);
4820
4821	SCSIREQ sr;
4822	uint8_t abCDB[10];
4823	uint8_t sense[96];
4824
4825	abCDB[0] = SCSI_SYNCHRONIZE_CACHE;
4826	abCDB[1] = 0; /* reserved */
4827	abCDB[2] = 0; /* LBA 0 */
4828	abCDB[3] = 0; /* LBA 0 */
4829	abCDB[4] = 0; /* LBA 0 */
4830	abCDB[5] = 0; /* LBA 0 */
4831	abCDB[6] = 0; /* reserved */
4832	abCDB[7] = 0; /* transfer everything to disk */
4833	abCDB[8] = 0; /* transfer everything to disk */
4834	abCDB[9] = 0; /* control */
4835
4836	sr.enmXfer = SCSIXFER_NONE;
4837	sr.cbCDB = sizeof(abCDB);
4838	sr.pvCDB = abCDB;
4839	sr.cbI2TData = 0;
4840	sr.paI2TSegs = NULL;
4841	sr.cI2TSegs = 0;
4842	sr.cbT2IData = 0;
4843	sr.paT2ISegs = NULL;
4844	sr.cT2ISegs = 0;
4845	sr.cbSense = sizeof(sense);
4846	sr.pvSense = sense;
4847
4848	rc = iscsiCommandSync(pImage, &sr, false, VINF_SUCCESS);
4849	if (RT_FAILURE(rc))
4850	AssertMsgFailed(("iscsiCommand(%s) -> %Rrc\n", pImage->pszTargetName, rc));
4851	LogFlowFunc(("returns %Rrc\n", rc));
4852	return rc;
4853	}
4854
4855	/** @copydoc VBOXHDDBACKEND::pfnGetVersion */
4856	static unsigned iscsiGetVersion(void *pBackendData)
4857	{
4858	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
4859	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
4860
4861	Assert(pImage);
4862	NOREF(pImage);
4863
4864	return 0;
4865	}
4866
4867	/** @copydoc VBOXHDDBACKEND::pfnGetSize */
4868	static uint64_t iscsiGetSize(void *pBackendData)
4869	{
4870	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
4871	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
4872
4873	Assert(pImage);
4874
4875	if (pImage)
4876	return pImage->cbSize;
4877	else
4878	return 0;
4879	}
4880
4881	/** @copydoc VBOXHDDBACKEND::pfnGetFileSize */
4882	static uint64_t iscsiGetFileSize(void *pBackendData)
4883	{
4884	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
4885	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
4886
4887	Assert(pImage);
4888	NOREF(pImage);
4889
4890	if (pImage)
4891	return pImage->cbSize;
4892	else
4893	return 0;
4894	}
4895
4896	/** @copydoc VBOXHDDBACKEND::pfnGetPCHSGeometry */
4897	static int iscsiGetPCHSGeometry(void *pBackendData, PVDGEOMETRY pPCHSGeometry)
4898	{
4899	LogFlowFunc(("pBackendData=%#p pPCHSGeometry=%#p\n", pBackendData, pPCHSGeometry));
4900	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
4901	int rc;
4902
4903	Assert(pImage);
4904
4905	if (pImage)
4906	rc = VERR_VD_GEOMETRY_NOT_SET;
4907	else
4908	rc = VERR_VD_NOT_OPENED;
4909
4910	LogFlowFunc(("returns %Rrc (PCHS=%u/%u/%u)\n", rc, pPCHSGeometry->cCylinders, pPCHSGeometry->cHeads, pPCHSGeometry->cSectors));
4911	return rc;
4912	}
4913
4914	/** @copydoc VBOXHDDBACKEND::pfnSetPCHSGeometry */
4915	static int iscsiSetPCHSGeometry(void *pBackendData, PCVDGEOMETRY pPCHSGeometry)
4916	{
4917	LogFlowFunc(("pBackendData=%#p pPCHSGeometry=%#p PCHS=%u/%u/%u\n", pBackendData, pPCHSGeometry, pPCHSGeometry->cCylinders, pPCHSGeometry->cHeads, pPCHSGeometry->cSectors));
4918	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
4919	int rc;
4920
4921	Assert(pImage);
4922
4923	if (pImage)
4924	{
4925	if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
4926	{
4927	rc = VERR_VD_IMAGE_READ_ONLY;
4928	goto out;
4929	}
4930	rc = VERR_VD_GEOMETRY_NOT_SET;
4931	}
4932	else
4933	rc = VERR_VD_NOT_OPENED;
4934
4935	out:
4936	LogFlowFunc(("returns %Rrc\n", rc));
4937	return rc;
4938	}
4939
4940	/** @copydoc VBOXHDDBACKEND::pfnGetLCHSGeometry */
4941	static int iscsiGetLCHSGeometry(void *pBackendData, PVDGEOMETRY pLCHSGeometry)
4942	{
4943	LogFlowFunc(("pBackendData=%#p pLCHSGeometry=%#p\n", pBackendData, pLCHSGeometry));
4944	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
4945	int rc;
4946
4947	Assert(pImage);
4948
4949	if (pImage)
4950	rc = VERR_VD_GEOMETRY_NOT_SET;
4951	else
4952	rc = VERR_VD_NOT_OPENED;
4953
4954	LogFlowFunc(("returns %Rrc (LCHS=%u/%u/%u)\n", rc, pLCHSGeometry->cCylinders, pLCHSGeometry->cHeads, pLCHSGeometry->cSectors));
4955	return rc;
4956	}
4957
4958	/** @copydoc VBOXHDDBACKEND::pfnSetLCHSGeometry */
4959	static int iscsiSetLCHSGeometry(void *pBackendData, PCVDGEOMETRY pLCHSGeometry)
4960	{
4961	LogFlowFunc(("pBackendData=%#p pLCHSGeometry=%#p LCHS=%u/%u/%u\n", pBackendData, pLCHSGeometry, pLCHSGeometry->cCylinders, pLCHSGeometry->cHeads, pLCHSGeometry->cSectors));
4962	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
4963	int rc;
4964
4965	Assert(pImage);
4966
4967	if (pImage)
4968	{
4969	if (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY)
4970	{
4971	rc = VERR_VD_IMAGE_READ_ONLY;
4972	goto out;
4973	}
4974	rc = VERR_VD_GEOMETRY_NOT_SET;
4975	}
4976	else
4977	rc = VERR_VD_NOT_OPENED;
4978
4979	out:
4980	LogFlowFunc(("returns %Rrc\n", rc));
4981	return rc;
4982	}
4983
4984	/** @copydoc VBOXHDDBACKEND::pfnGetImageFlags */
4985	static unsigned iscsiGetImageFlags(void *pBackendData)
4986	{
4987	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
4988	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
4989	unsigned uImageFlags;
4990
4991	Assert(pImage);
4992	NOREF(pImage);
4993
4994	uImageFlags = VD_IMAGE_FLAGS_FIXED;
4995
4996	LogFlowFunc(("returns %#x\n", uImageFlags));
4997	return uImageFlags;
4998	}
4999
5000	/** @copydoc VBOXHDDBACKEND::pfnGetOpenFlags */
5001	static unsigned iscsiGetOpenFlags(void *pBackendData)
5002	{
5003	LogFlowFunc(("pBackendData=%#p\n", pBackendData));
5004	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
5005	unsigned uOpenFlags;
5006
5007	Assert(pImage);
5008
5009	if (pImage)
5010	uOpenFlags = pImage->uOpenFlags;
5011	else
5012	uOpenFlags = 0;
5013
5014	LogFlowFunc(("returns %#x\n", uOpenFlags));
5015	return uOpenFlags;
5016	}
5017
5018	/** @copydoc VBOXHDDBACKEND::pfnSetOpenFlags */
5019	static int iscsiSetOpenFlags(void *pBackendData, unsigned uOpenFlags)
5020	{
5021	LogFlowFunc(("pBackendData=%#p\n uOpenFlags=%#x", pBackendData, uOpenFlags));
5022	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
5023	int rc;
5024
5025	/* Image must be opened and the new flags must be valid. */
5026	if (!pImage \|\| (uOpenFlags & ~( VD_OPEN_FLAGS_READONLY \| VD_OPEN_FLAGS_INFO
5027	\| VD_OPEN_FLAGS_ASYNC_IO \| VD_OPEN_FLAGS_SHAREABLE
5028	\| VD_OPEN_FLAGS_SEQUENTIAL \| VD_OPEN_FLAGS_SKIP_CONSISTENCY_CHECKS)))
5029	{
5030	rc = VERR_INVALID_PARAMETER;
5031	goto out;
5032	}
5033
5034	/* Implement this operation via reopening the image if we actually need
5035	* to do something. A read/write -> readonly transition doesn't need a
5036	* reopen. In the other direction we don't have the necessary information
5037	* as the "disk is readonly" flag is thrown away. Can be optimized too,
5038	* but it's not worth the effort at the moment. */
5039	if ( !(uOpenFlags & VD_OPEN_FLAGS_READONLY)
5040	&& (pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY))
5041	{
5042	iscsiFreeImage(pImage, false);
5043	rc = iscsiOpenImage(pImage, uOpenFlags);
5044	}
5045	else
5046	{
5047	pImage->uOpenFlags = uOpenFlags;
5048	rc = VINF_SUCCESS;
5049	}
5050	out:
5051	LogFlowFunc(("returns %Rrc\n", rc));
5052	return rc;
5053	}
5054
5055	/** @copydoc VBOXHDDBACKEND::pfnGetComment */
5056	static int iscsiGetComment(void pBackendData, char pszComment,
5057	size_t cbComment)
5058	{
5059	LogFlowFunc(("pBackendData=%#p pszComment=%#p cbComment=%zu\n", pBackendData, pszComment, cbComment));
5060	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
5061	int rc;
5062
5063	Assert(pImage);
5064
5065	if (pImage)
5066	rc = VERR_NOT_SUPPORTED;
5067	else
5068	rc = VERR_VD_NOT_OPENED;
5069
5070	LogFlowFunc(("returns %Rrc comment='%s'\n", rc, pszComment));
5071	return rc;
5072	}
5073
5074	/** @copydoc VBOXHDDBACKEND::pfnSetComment */
5075	static int iscsiSetComment(void pBackendData, const char pszComment)
5076	{
5077	LogFlowFunc(("pBackendData=%#p pszComment=\"%s\"\n", pBackendData, pszComment));
5078	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
5079	int rc;
5080
5081	Assert(pImage);
5082
5083	if (pImage)
5084	{
5085	if (!(pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY))
5086	rc = VERR_NOT_SUPPORTED;
5087	else
5088	rc = VERR_VD_IMAGE_READ_ONLY;
5089	}
5090	else
5091	rc = VERR_VD_NOT_OPENED;
5092
5093	LogFlowFunc(("returns %Rrc\n", rc));
5094	return rc;
5095	}
5096
5097	/** @copydoc VBOXHDDBACKEND::pfnGetUuid */
5098	static int iscsiGetUuid(void *pBackendData, PRTUUID pUuid)
5099	{
5100	LogFlowFunc(("pBackendData=%#p pUuid=%#p\n", pBackendData, pUuid));
5101	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
5102	int rc;
5103
5104	Assert(pImage);
5105
5106	if (pImage)
5107	rc = VERR_NOT_SUPPORTED;
5108	else
5109	rc = VERR_VD_NOT_OPENED;
5110
5111	LogFlowFunc(("returns %Rrc (%RTuuid)\n", rc, pUuid));
5112	return rc;
5113	}
5114
5115	/** @copydoc VBOXHDDBACKEND::pfnSetUuid */
5116	static int iscsiSetUuid(void *pBackendData, PCRTUUID pUuid)
5117	{
5118	LogFlowFunc(("pBackendData=%#p Uuid=%RTuuid\n", pBackendData, pUuid));
5119	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
5120	int rc;
5121
5122	LogFlowFunc(("%RTuuid\n", pUuid));
5123	Assert(pImage);
5124
5125	if (pImage)
5126	{
5127	if (!(pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY))
5128	rc = VERR_NOT_SUPPORTED;
5129	else
5130	rc = VERR_VD_IMAGE_READ_ONLY;
5131	}
5132	else
5133	rc = VERR_VD_NOT_OPENED;
5134
5135	LogFlowFunc(("returns %Rrc\n", rc));
5136	return rc;
5137	}
5138
5139	/** @copydoc VBOXHDDBACKEND::pfnGetModificationUuid */
5140	static int iscsiGetModificationUuid(void *pBackendData, PRTUUID pUuid)
5141	{
5142	LogFlowFunc(("pBackendData=%#p pUuid=%#p\n", pBackendData, pUuid));
5143	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
5144	int rc;
5145
5146	Assert(pImage);
5147
5148	if (pImage)
5149	rc = VERR_NOT_SUPPORTED;
5150	else
5151	rc = VERR_VD_NOT_OPENED;
5152
5153	LogFlowFunc(("returns %Rrc (%RTuuid)\n", rc, pUuid));
5154	return rc;
5155	}
5156
5157	/** @copydoc VBOXHDDBACKEND::pfnSetModificationUuid */
5158	static int iscsiSetModificationUuid(void *pBackendData, PCRTUUID pUuid)
5159	{
5160	LogFlowFunc(("pBackendData=%#p Uuid=%RTuuid\n", pBackendData, pUuid));
5161	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
5162	int rc;
5163
5164	LogFlowFunc(("%RTuuid\n", pUuid));
5165	Assert(pImage);
5166
5167	if (pImage)
5168	{
5169	if (!(pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY))
5170	rc = VERR_NOT_SUPPORTED;
5171	else
5172	rc = VERR_VD_IMAGE_READ_ONLY;
5173	}
5174	else
5175	rc = VERR_VD_NOT_OPENED;
5176
5177	LogFlowFunc(("returns %Rrc\n", rc));
5178	return rc;
5179	}
5180
5181	/** @copydoc VBOXHDDBACKEND::pfnGetParentUuid */
5182	static int iscsiGetParentUuid(void *pBackendData, PRTUUID pUuid)
5183	{
5184	LogFlowFunc(("pBackendData=%#p pUuid=%#p\n", pBackendData, pUuid));
5185	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
5186	int rc;
5187
5188	Assert(pImage);
5189
5190	if (pImage)
5191	rc = VERR_NOT_SUPPORTED;
5192	else
5193	rc = VERR_VD_NOT_OPENED;
5194
5195	LogFlowFunc(("returns %Rrc (%RTuuid)\n", rc, pUuid));
5196	return rc;
5197	}
5198
5199	/** @copydoc VBOXHDDBACKEND::pfnSetParentUuid */
5200	static int iscsiSetParentUuid(void *pBackendData, PCRTUUID pUuid)
5201	{
5202	LogFlowFunc(("pBackendData=%#p Uuid=%RTuuid\n", pBackendData, pUuid));
5203	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
5204	int rc;
5205
5206	LogFlowFunc(("%RTuuid\n", pUuid));
5207	Assert(pImage);
5208
5209	if (pImage)
5210	{
5211	if (!(pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY))
5212	rc = VERR_NOT_SUPPORTED;
5213	else
5214	rc = VERR_VD_IMAGE_READ_ONLY;
5215	}
5216	else
5217	rc = VERR_VD_NOT_OPENED;
5218
5219	LogFlowFunc(("returns %Rrc\n", rc));
5220	return rc;
5221	}
5222
5223	/** @copydoc VBOXHDDBACKEND::pfnGetParentModificationUuid */
5224	static int iscsiGetParentModificationUuid(void *pBackendData, PRTUUID pUuid)
5225	{
5226	LogFlowFunc(("pBackendData=%#p pUuid=%#p\n", pBackendData, pUuid));
5227	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
5228	int rc;
5229
5230	Assert(pImage);
5231
5232	if (pImage)
5233	rc = VERR_NOT_SUPPORTED;
5234	else
5235	rc = VERR_VD_NOT_OPENED;
5236
5237	LogFlowFunc(("returns %Rrc (%RTuuid)\n", rc, pUuid));
5238	return rc;
5239	}
5240
5241	/** @copydoc VBOXHDDBACKEND::pfnSetParentModificationUuid */
5242	static int iscsiSetParentModificationUuid(void *pBackendData, PCRTUUID pUuid)
5243	{
5244	LogFlowFunc(("pBackendData=%#p Uuid=%RTuuid\n", pBackendData, pUuid));
5245	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
5246	int rc;
5247
5248	LogFlowFunc(("%RTuuid\n", pUuid));
5249	Assert(pImage);
5250
5251	if (pImage)
5252	{
5253	if (!(pImage->uOpenFlags & VD_OPEN_FLAGS_READONLY))
5254	rc = VERR_NOT_SUPPORTED;
5255	else
5256	rc = VERR_VD_IMAGE_READ_ONLY;
5257	}
5258	else
5259	rc = VERR_VD_NOT_OPENED;
5260
5261	LogFlowFunc(("returns %Rrc\n", rc));
5262	return rc;
5263	}
5264
5265	/** @copydoc VBOXHDDBACKEND::pfnDump */
5266	static void iscsiDump(void *pBackendData)
5267	{
5268	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
5269
5270	Assert(pImage);
5271	if (pImage)
5272	{
5273	/** @todo put something useful here */
5274	vdIfErrorMessage(pImage->pIfError, "Header: cVolume=%u\n", pImage->cVolume);
5275	}
5276	}
5277
5278	/** @copydoc VBOXHDDBACKEND::pfnAsyncRead */
5279	static int iscsiAsyncRead(void *pBackendData, uint64_t uOffset, size_t cbToRead,
5280	PVDIOCTX pIoCtx, size_t *pcbActuallyRead)
5281	{
5282	LogFlowFunc(("pBackendData=%p uOffset=%#llx pIoCtx=%#p cbToRead=%u pcbActuallyRead=%p\n",
5283	pBackendData, uOffset, pIoCtx, cbToRead, pcbActuallyRead));
5284	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
5285	int rc = VINF_SUCCESS;
5286
5287	if (uOffset + cbToRead > pImage->cbSize)
5288	return VERR_INVALID_PARAMETER;
5289
5290	/*
5291	* Clip read size to a value which is supported by the target.
5292	*/
5293	cbToRead = RT_MIN(cbToRead, pImage->cbRecvDataLength);
5294
5295	unsigned cT2ISegs = 0;
5296	size_t cbSegs = 0;
5297
5298	/* Get the number of segments. */
5299	cbSegs = pImage->pIfIo->pfnIoCtxSegArrayCreate(pImage->pIfIo->Core.pvUser, pIoCtx,
5300	NULL, &cT2ISegs, cbToRead);
5301	Assert(cbSegs == cbToRead);
5302
5303	PSCSIREQASYNC pReqAsync = (PSCSIREQASYNC)RTMemAllocZ(RT_OFFSETOF(SCSIREQASYNC, aSegs[cT2ISegs]));
5304	if (RT_LIKELY(pReqAsync))
5305	{
5306	PSCSIREQ pReq = (PSCSIREQ)RTMemAllocZ(sizeof(SCSIREQ));
5307	if (pReq)
5308	{
5309	uint64_t lba;
5310	uint16_t tls;
5311	uint8_t *pbCDB = &pReqAsync->abCDB[0];
5312	size_t cbCDB;
5313
5314	lba = uOffset / pImage->cbSector;
5315	tls = (uint16_t)(cbToRead / pImage->cbSector);
5316
5317	cbSegs = pImage->pIfIo->pfnIoCtxSegArrayCreate(pImage->pIfIo->Core.pvUser, pIoCtx,
5318	&pReqAsync->aSegs[0],
5319	&cT2ISegs, cbToRead);
5320	Assert(cbSegs == cbToRead);
5321	pReqAsync->cT2ISegs = cT2ISegs;
5322	pReqAsync->pIoCtx = pIoCtx;
5323	pReqAsync->pScsiReq = pReq;
5324	pReqAsync->cSenseRetries = 10;
5325	pReqAsync->rcSense = VERR_READ_ERROR;
5326
5327	if (pImage->cVolume < _4G)
5328	{
5329	cbCDB = 10;
5330	pbCDB[0] = SCSI_READ_10;
5331	pbCDB[1] = 0; /* reserved */
5332	pbCDB[2] = (lba >> 24) & 0xff;
5333	pbCDB[3] = (lba >> 16) & 0xff;
5334	pbCDB[4] = (lba >> 8) & 0xff;
5335	pbCDB[5] = lba & 0xff;
5336	pbCDB[6] = 0; /* reserved */
5337	pbCDB[7] = (tls >> 8) & 0xff;
5338	pbCDB[8] = tls & 0xff;
5339	pbCDB[9] = 0; /* control */
5340	}
5341	else
5342	{
5343	cbCDB = 16;
5344	pbCDB[0] = SCSI_READ_16;
5345	pbCDB[1] = 0; /* reserved */
5346	pbCDB[2] = (lba >> 56) & 0xff;
5347	pbCDB[3] = (lba >> 48) & 0xff;
5348	pbCDB[4] = (lba >> 40) & 0xff;
5349	pbCDB[5] = (lba >> 32) & 0xff;
5350	pbCDB[6] = (lba >> 24) & 0xff;
5351	pbCDB[7] = (lba >> 16) & 0xff;
5352	pbCDB[8] = (lba >> 8) & 0xff;
5353	pbCDB[9] = lba & 0xff;
5354	pbCDB[10] = 0; /* tls unused */
5355	pbCDB[11] = 0; /* tls unused */
5356	pbCDB[12] = (tls >> 8) & 0xff;
5357	pbCDB[13] = tls & 0xff;
5358	pbCDB[14] = 0; /* reserved */
5359	pbCDB[15] = 0; /* reserved */
5360	}
5361
5362	pReq->enmXfer = SCSIXFER_FROM_TARGET;
5363	pReq->cbCDB = cbCDB;
5364	pReq->pvCDB = pReqAsync->abCDB;
5365	pReq->cbI2TData = 0;
5366	pReq->paI2TSegs = NULL;
5367	pReq->cI2TSegs = 0;
5368	pReq->cbT2IData = cbToRead;
5369	pReq->paT2ISegs = &pReqAsync->aSegs[pReqAsync->cI2TSegs];
5370	pReq->cT2ISegs = pReqAsync->cT2ISegs;
5371	pReq->cbSense = sizeof(pReqAsync->abSense);
5372	pReq->pvSense = pReqAsync->abSense;
5373
5374	rc = iscsiCommandAsync(pImage, pReq, iscsiCommandAsyncComplete, pReqAsync);
5375	if (RT_FAILURE(rc))
5376	AssertMsgFailed(("iscsiCommand(%s, %#llx) -> %Rrc\n", pImage->pszTargetName, uOffset, rc));
5377	else
5378	{
5379	*pcbActuallyRead = cbToRead;
5380	return VERR_VD_IOCTX_HALT; /* Halt the I/O context until further notification from the I/O thread. */
5381	}
5382
5383	RTMemFree(pReq);
5384	}
5385	else
5386	rc = VERR_NO_MEMORY;
5387
5388	RTMemFree(pReqAsync);
5389	}
5390	else
5391	rc = VERR_NO_MEMORY;
5392
5393	LogFlowFunc(("returns rc=%Rrc\n", rc));
5394	return rc;
5395	}
5396
5397	/** @copydoc VBOXHDDBACKEND::pfnAsyncWrite */
5398	static int iscsiAsyncWrite(void *pBackendData, uint64_t uOffset, size_t cbToWrite,
5399	PVDIOCTX pIoCtx,
5400	size_t pcbWriteProcess, size_t pcbPreRead,
5401	size_t *pcbPostRead, unsigned fWrite)
5402	{
5403	LogFlowFunc(("pBackendData=%p uOffset=%llu pIoCtx=%#p cbToWrite=%u pcbWriteProcess=%p pcbPreRead=%p pcbPostRead=%p fWrite=%u\n",
5404	pBackendData, uOffset, pIoCtx, cbToWrite, pcbWriteProcess, pcbPreRead, pcbPostRead, fWrite));
5405	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
5406	int rc = VINF_SUCCESS;
5407
5408	AssertPtr(pImage);
5409	Assert(uOffset % 512 == 0);
5410	Assert(cbToWrite % 512 == 0);
5411
5412	if (uOffset + cbToWrite > pImage->cbSize)
5413	return VERR_INVALID_PARAMETER;
5414
5415	/*
5416	* Clip read size to a value which is supported by the target.
5417	*/
5418	cbToWrite = RT_MIN(cbToWrite, pImage->cbSendDataLength);
5419
5420	unsigned cI2TSegs = 0;
5421	size_t cbSegs = 0;
5422
5423	/* Get the number of segments. */
5424	cbSegs = pImage->pIfIo->pfnIoCtxSegArrayCreate(pImage->pIfIo->Core.pvUser, pIoCtx,
5425	NULL, &cI2TSegs, cbToWrite);
5426	Assert(cbSegs == cbToWrite);
5427
5428	PSCSIREQASYNC pReqAsync = (PSCSIREQASYNC)RTMemAllocZ(RT_OFFSETOF(SCSIREQASYNC, aSegs[cI2TSegs]));
5429	if (RT_LIKELY(pReqAsync))
5430	{
5431	PSCSIREQ pReq = (PSCSIREQ)RTMemAllocZ(sizeof(SCSIREQ));
5432	if (pReq)
5433	{
5434	uint64_t lba;
5435	uint16_t tls;
5436	uint8_t *pbCDB = &pReqAsync->abCDB[0];
5437	size_t cbCDB;
5438
5439	lba = uOffset / pImage->cbSector;
5440	tls = (uint16_t)(cbToWrite / pImage->cbSector);
5441
5442	cbSegs = pImage->pIfIo->pfnIoCtxSegArrayCreate(pImage->pIfIo->Core.pvUser, pIoCtx,
5443	&pReqAsync->aSegs[0],
5444	&cI2TSegs, cbToWrite);
5445	Assert(cbSegs == cbToWrite);
5446	pReqAsync->cI2TSegs = cI2TSegs;
5447	pReqAsync->pIoCtx = pIoCtx;
5448	pReqAsync->pScsiReq = pReq;
5449	pReqAsync->cSenseRetries = 10;
5450	pReqAsync->rcSense = VERR_WRITE_ERROR;
5451
5452	if (pImage->cVolume < _4G)
5453	{
5454	cbCDB = 10;
5455	pbCDB[0] = SCSI_WRITE_10;
5456	pbCDB[1] = 0; /* reserved */
5457	pbCDB[2] = (lba >> 24) & 0xff;
5458	pbCDB[3] = (lba >> 16) & 0xff;
5459	pbCDB[4] = (lba >> 8) & 0xff;
5460	pbCDB[5] = lba & 0xff;
5461	pbCDB[6] = 0; /* reserved */
5462	pbCDB[7] = (tls >> 8) & 0xff;
5463	pbCDB[8] = tls & 0xff;
5464	pbCDB[9] = 0; /* control */
5465	}
5466	else
5467	{
5468	cbCDB = 16;
5469	pbCDB[0] = SCSI_WRITE_16;
5470	pbCDB[1] = 0; /* reserved */
5471	pbCDB[2] = (lba >> 56) & 0xff;
5472	pbCDB[3] = (lba >> 48) & 0xff;
5473	pbCDB[4] = (lba >> 40) & 0xff;
5474	pbCDB[5] = (lba >> 32) & 0xff;
5475	pbCDB[6] = (lba >> 24) & 0xff;
5476	pbCDB[7] = (lba >> 16) & 0xff;
5477	pbCDB[8] = (lba >> 8) & 0xff;
5478	pbCDB[9] = lba & 0xff;
5479	pbCDB[10] = 0; /* tls unused */
5480	pbCDB[11] = 0; /* tls unused */
5481	pbCDB[12] = (tls >> 8) & 0xff;
5482	pbCDB[13] = tls & 0xff;
5483	pbCDB[14] = 0; /* reserved */
5484	pbCDB[15] = 0; /* reserved */
5485	}
5486
5487	pReq->enmXfer = SCSIXFER_TO_TARGET;
5488	pReq->cbCDB = cbCDB;
5489	pReq->pvCDB = pReqAsync->abCDB;
5490	pReq->cbI2TData = cbToWrite;
5491	pReq->paI2TSegs = &pReqAsync->aSegs[0];
5492	pReq->cI2TSegs = pReqAsync->cI2TSegs;
5493	pReq->cbT2IData = 0;
5494	pReq->paT2ISegs = NULL;
5495	pReq->cT2ISegs = 0;
5496	pReq->cbSense = sizeof(pReqAsync->abSense);
5497	pReq->pvSense = pReqAsync->abSense;
5498
5499	rc = iscsiCommandAsync(pImage, pReq, iscsiCommandAsyncComplete, pReqAsync);
5500	if (RT_FAILURE(rc))
5501	AssertMsgFailed(("iscsiCommand(%s, %#llx) -> %Rrc\n", pImage->pszTargetName, uOffset, rc));
5502	else
5503	{
5504	*pcbWriteProcess = cbToWrite;
5505	return VERR_VD_IOCTX_HALT; /* Halt the I/O context until further notification from the I/O thread. */
5506	}
5507
5508	RTMemFree(pReq);
5509	}
5510	else
5511	rc = VERR_NO_MEMORY;
5512
5513	RTMemFree(pReqAsync);
5514	}
5515	else
5516	rc = VERR_NO_MEMORY;
5517
5518	LogFlowFunc(("returns rc=%Rrc\n", rc));
5519	return rc;
5520	}
5521
5522	/** @copydoc VBOXHDDBACKEND::pfnAsyncFlush */
5523	static int iscsiAsyncFlush(void *pBackendData, PVDIOCTX pIoCtx)
5524	{
5525	LogFlowFunc(("pBackendData=%p pIoCtx=%#p\n", pBackendData, pIoCtx));
5526	PISCSIIMAGE pImage = (PISCSIIMAGE)pBackendData;
5527	int rc = VINF_SUCCESS;
5528
5529	PSCSIREQASYNC pReqAsync = (PSCSIREQASYNC)RTMemAllocZ(sizeof(SCSIREQASYNC));
5530	if (RT_LIKELY(pReqAsync))
5531	{
5532	PSCSIREQ pReq = (PSCSIREQ)RTMemAllocZ(sizeof(SCSIREQ));
5533	if (pReq)
5534	{
5535	uint8_t *pbCDB = &pReqAsync->abCDB[0];
5536
5537	pReqAsync->pIoCtx = pIoCtx;
5538	pReqAsync->pScsiReq = pReq;
5539	pReqAsync->cSenseRetries = 0;
5540	pReqAsync->rcSense = VINF_SUCCESS;
5541
5542	pbCDB[0] = SCSI_SYNCHRONIZE_CACHE;
5543	pbCDB[1] = 0; /* reserved */
5544	pbCDB[2] = 0; /* reserved */
5545	pbCDB[3] = 0; /* reserved */
5546	pbCDB[4] = 0; /* reserved */
5547	pbCDB[5] = 0; /* reserved */
5548	pbCDB[6] = 0; /* reserved */
5549	pbCDB[7] = 0; /* reserved */
5550	pbCDB[8] = 0; /* reserved */
5551	pbCDB[9] = 0; /* control */
5552
5553	pReq->enmXfer = SCSIXFER_NONE;
5554	pReq->cbCDB = 10;
5555	pReq->pvCDB = pReqAsync->abCDB;
5556	pReq->cbI2TData = 0;
5557	pReq->paI2TSegs = NULL;
5558	pReq->cI2TSegs = 0;
5559	pReq->cbT2IData = 0;
5560	pReq->paT2ISegs = NULL;
5561	pReq->cT2ISegs = 0;
5562	pReq->cbSense = sizeof(pReqAsync->abSense);
5563	pReq->pvSense = pReqAsync->abSense;
5564
5565	rc = iscsiCommandAsync(pImage, pReq, iscsiCommandAsyncComplete, pReqAsync);
5566	if (RT_FAILURE(rc))
5567	AssertMsgFailed(("iscsiCommand(%s) -> %Rrc\n", pImage->pszTargetName, rc));
5568	else
5569	return VERR_VD_IOCTX_HALT; /* Halt the I/O context until further notification from the I/O thread. */
5570
5571	RTMemFree(pReq);
5572	}
5573	else
5574	rc = VERR_NO_MEMORY;
5575
5576	RTMemFree(pReqAsync);
5577	}
5578	else
5579	rc = VERR_NO_MEMORY;
5580
5581	LogFlowFunc(("returns rc=%Rrc\n", rc));
5582	return rc;
5583	}
5584
5585	/** @copydoc VBOXHDDBACKEND::pfnComposeLocation */
5586	static int iscsiComposeLocation(PVDINTERFACE pConfig, char **pszLocation)
5587	{
5588	char *pszTarget = NULL;
5589	char *pszLUN = NULL;
5590	char *pszAddress = NULL;
5591	int rc = VDCFGQueryStringAlloc(VDIfConfigGet(pConfig), "TargetName", &pszTarget);
5592	if (RT_SUCCESS(rc))
5593	{
5594	rc = VDCFGQueryStringAlloc(VDIfConfigGet(pConfig), "LUN", &pszLUN);
5595	if (RT_SUCCESS(rc))
5596	{
5597	rc = VDCFGQueryStringAlloc(VDIfConfigGet(pConfig), "TargetAddress", &pszAddress);
5598	if (RT_SUCCESS(rc))
5599	{
5600	if (RTStrAPrintf(pszLocation, "iscsi://%s/%s/%s",
5601	pszAddress, pszTarget, pszLUN) < 0)
5602	rc = VERR_NO_MEMORY;
5603	}
5604	}
5605	}
5606	RTMemFree(pszTarget);
5607	RTMemFree(pszLUN);
5608	RTMemFree(pszAddress);
5609	return rc;
5610	}
5611
5612	/** @copydoc VBOXHDDBACKEND::pfnComposeName */
5613	static int iscsiComposeName(PVDINTERFACE pConfig, char **pszName)
5614	{
5615	char *pszTarget = NULL;
5616	char *pszLUN = NULL;
5617	char *pszAddress = NULL;
5618	int rc = VDCFGQueryStringAlloc(VDIfConfigGet(pConfig), "TargetName", &pszTarget);
5619	if (RT_SUCCESS(rc))
5620	{
5621	rc = VDCFGQueryStringAlloc(VDIfConfigGet(pConfig), "LUN", &pszLUN);
5622	if (RT_SUCCESS(rc))
5623	{
5624	rc = VDCFGQueryStringAlloc(VDIfConfigGet(pConfig), "TargetAddress", &pszAddress);
5625	if (RT_SUCCESS(rc))
5626	{
5627	/** @todo think about a nicer looking location scheme for iSCSI */
5628	if (RTStrAPrintf(pszName, "%s/%s/%s",
5629	pszAddress, pszTarget, pszLUN) < 0)
5630	rc = VERR_NO_MEMORY;
5631	}
5632	}
5633	}
5634	RTMemFree(pszTarget);
5635	RTMemFree(pszLUN);
5636	RTMemFree(pszAddress);
5637
5638	return rc;
5639	}
5640
5641
5642	VBOXHDDBACKEND g_ISCSIBackend =
5643	{
5644	/* pszBackendName */
5645	"iSCSI",
5646	/* cbSize */
5647	sizeof(VBOXHDDBACKEND),
5648	/* uBackendCaps */
5649	VD_CAP_CONFIG \| VD_CAP_TCPNET \| VD_CAP_ASYNC,
5650	/* papszFileExtensions */
5651	NULL,
5652	/* paConfigInfo */
5653	s_iscsiConfigInfo,
5654	/* hPlugin */
5655	NIL_RTLDRMOD,
5656	/* pfnCheckIfValid */
5657	iscsiCheckIfValid,
5658	/* pfnOpen */
5659	iscsiOpen,
5660	/* pfnCreate */
5661	iscsiCreate,
5662	/* pfnRename */
5663	NULL,
5664	/* pfnClose */
5665	iscsiClose,
5666	/* pfnRead */
5667	iscsiRead,
5668	/* pfnWrite */
5669	iscsiWrite,
5670	/* pfnFlush */
5671	iscsiFlush,
5672	/* pfnGetVersion */
5673	iscsiGetVersion,
5674	/* pfnGetSize */
5675	iscsiGetSize,
5676	/* pfnGetFileSize */
5677	iscsiGetFileSize,
5678	/* pfnGetPCHSGeometry */
5679	iscsiGetPCHSGeometry,
5680	/* pfnSetPCHSGeometry */
5681	iscsiSetPCHSGeometry,
5682	/* pfnGetLCHSGeometry */
5683	iscsiGetLCHSGeometry,
5684	/* pfnSetLCHSGeometry */
5685	iscsiSetLCHSGeometry,
5686	/* pfnGetImageFlags */
5687	iscsiGetImageFlags,
5688	/* pfnGetOpenFlags */
5689	iscsiGetOpenFlags,
5690	/* pfnSetOpenFlags */
5691	iscsiSetOpenFlags,
5692	/* pfnGetComment */
5693	iscsiGetComment,
5694	/* pfnSetComment */
5695	iscsiSetComment,
5696	/* pfnGetUuid */
5697	iscsiGetUuid,
5698	/* pfnSetUuid */
5699	iscsiSetUuid,
5700	/* pfnGetModificationUuid */
5701	iscsiGetModificationUuid,
5702	/* pfnSetModificationUuid */
5703	iscsiSetModificationUuid,
5704	/* pfnGetParentUuid */
5705	iscsiGetParentUuid,
5706	/* pfnSetParentUuid */
5707	iscsiSetParentUuid,
5708	/* pfnGetParentModificationUuid */
5709	iscsiGetParentModificationUuid,
5710	/* pfnSetParentModificationUuid */
5711	iscsiSetParentModificationUuid,
5712	/* pfnDump */
5713	iscsiDump,
5714	/* pfnGetTimeStamp */
5715	NULL,
5716	/* pfnGetParentTimeStamp */
5717	NULL,
5718	/* pfnSetParentTimeStamp */
5719	NULL,
5720	/* pfnGetParentFilename */
5721	NULL,
5722	/* pfnSetParentFilename */
5723	NULL,
5724	/* pfnAsyncRead */
5725	iscsiAsyncRead,
5726	/* pfnAsyncWrite */
5727	iscsiAsyncWrite,
5728	/* pfnAsyncFlush */
5729	iscsiAsyncFlush,
5730	/* pfnComposeLocation */
5731	iscsiComposeLocation,
5732	/* pfnComposeName */
5733	iscsiComposeName,
5734	/* pfnCompact */
5735	NULL,
5736	/* pfnResize */
5737	NULL,
5738	/* pfnDiscard */
5739	NULL,
5740	/* pfnAsyncDiscard */
5741	NULL,
5742	/* pfnRepair */
5743	NULL
5744	};

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source: vbox/trunk/src/VBox/Storage/ISCSI.cpp@ 44232

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