xref: /openbmc/linux/include/scsi/iscsi_proto.h (revision 9ffc93f2)
1 /*
2  * RFC 3720 (iSCSI) protocol data types
3  *
4  * Copyright (C) 2005 Dmitry Yusupov
5  * Copyright (C) 2005 Alex Aizman
6  * maintained by open-iscsi@googlegroups.com
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published
10  * by the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * General Public License for more details.
17  *
18  * See the file COPYING included with this distribution for more details.
19  */
20 
21 #ifndef ISCSI_PROTO_H
22 #define ISCSI_PROTO_H
23 
24 #include <linux/types.h>
25 #include <scsi/scsi.h>
26 
27 #define ISCSI_DRAFT20_VERSION	0x00
28 
29 /* default iSCSI listen port for incoming connections */
30 #define ISCSI_LISTEN_PORT	3260
31 
32 /* iSCSI header length */
33 #define ISCSI_HDR_LEN		48
34 
35 /* iSCSI CRC32C length */
36 #define ISCSI_CRC_LEN		4
37 
38 /* Padding word length */
39 #define ISCSI_PAD_LEN		4
40 
41 /*
42  * Serial Number Arithmetic, 32 bits, RFC1982
43  */
44 
45 static inline int iscsi_sna_lt(u32 n1, u32 n2)
46 {
47 	return (s32)(n1 - n2) < 0;
48 }
49 
50 static inline int iscsi_sna_lte(u32 n1, u32 n2)
51 {
52 	return (s32)(n1 - n2) <= 0;
53 }
54 
55 static inline int iscsi_sna_gt(u32 n1, u32 n2)
56 {
57 	return (s32)(n1 - n2) > 0;
58 }
59 
60 static inline int iscsi_sna_gte(u32 n1, u32 n2)
61 {
62 	return (s32)(n1 - n2) >= 0;
63 }
64 
65 /*
66  * useful common(control and data pathes) macro
67  */
68 #define ntoh24(p) (((p)[0] << 16) | ((p)[1] << 8) | ((p)[2]))
69 #define hton24(p, v) { \
70         p[0] = (((v) >> 16) & 0xFF); \
71         p[1] = (((v) >> 8) & 0xFF); \
72         p[2] = ((v) & 0xFF); \
73 }
74 #define zero_data(p) {p[0]=0;p[1]=0;p[2]=0;}
75 
76 /* initiator tags; opaque for target */
77 typedef uint32_t __bitwise__ itt_t;
78 /* below makes sense only for initiator that created this tag */
79 #define build_itt(itt, age) ((__force itt_t)\
80 	((itt) | ((age) << ISCSI_AGE_SHIFT)))
81 #define get_itt(itt) ((__force uint32_t)(itt_t)(itt) & ISCSI_ITT_MASK)
82 #define RESERVED_ITT ((__force itt_t)0xffffffff)
83 
84 /*
85  * iSCSI Template Message Header
86  */
87 struct iscsi_hdr {
88 	uint8_t		opcode;
89 	uint8_t		flags;		/* Final bit */
90 	uint8_t		rsvd2[2];
91 	uint8_t		hlength;	/* AHSs total length */
92 	uint8_t		dlength[3];	/* Data length */
93 	struct scsi_lun	lun;
94 	itt_t		itt;		/* Initiator Task Tag, opaque for target */
95 	__be32		ttt;		/* Target Task Tag */
96 	__be32		statsn;
97 	__be32		exp_statsn;
98 	__be32		max_statsn;
99 	uint8_t		other[12];
100 };
101 
102 /************************* RFC 3720 Begin *****************************/
103 
104 #define ISCSI_RESERVED_TAG		0xffffffff
105 
106 /* Opcode encoding bits */
107 #define ISCSI_OP_RETRY			0x80
108 #define ISCSI_OP_IMMEDIATE		0x40
109 #define ISCSI_OPCODE_MASK		0x3F
110 
111 /* Initiator Opcode values */
112 #define ISCSI_OP_NOOP_OUT		0x00
113 #define ISCSI_OP_SCSI_CMD		0x01
114 #define ISCSI_OP_SCSI_TMFUNC		0x02
115 #define ISCSI_OP_LOGIN			0x03
116 #define ISCSI_OP_TEXT			0x04
117 #define ISCSI_OP_SCSI_DATA_OUT		0x05
118 #define ISCSI_OP_LOGOUT			0x06
119 #define ISCSI_OP_SNACK			0x10
120 
121 #define ISCSI_OP_VENDOR1_CMD		0x1c
122 #define ISCSI_OP_VENDOR2_CMD		0x1d
123 #define ISCSI_OP_VENDOR3_CMD		0x1e
124 #define ISCSI_OP_VENDOR4_CMD		0x1f
125 
126 /* Target Opcode values */
127 #define ISCSI_OP_NOOP_IN		0x20
128 #define ISCSI_OP_SCSI_CMD_RSP		0x21
129 #define ISCSI_OP_SCSI_TMFUNC_RSP	0x22
130 #define ISCSI_OP_LOGIN_RSP		0x23
131 #define ISCSI_OP_TEXT_RSP		0x24
132 #define ISCSI_OP_SCSI_DATA_IN		0x25
133 #define ISCSI_OP_LOGOUT_RSP		0x26
134 #define ISCSI_OP_R2T			0x31
135 #define ISCSI_OP_ASYNC_EVENT		0x32
136 #define ISCSI_OP_REJECT			0x3f
137 
138 struct iscsi_ahs_hdr {
139 	__be16 ahslength;
140 	uint8_t ahstype;
141 	uint8_t ahspec[5];
142 };
143 
144 #define ISCSI_AHSTYPE_CDB		1
145 #define ISCSI_AHSTYPE_RLENGTH		2
146 #define ISCSI_CDB_SIZE			16
147 
148 /* iSCSI PDU Header */
149 struct iscsi_scsi_req {
150 	uint8_t opcode;
151 	uint8_t flags;
152 	__be16 rsvd2;
153 	uint8_t hlength;
154 	uint8_t dlength[3];
155 	struct scsi_lun lun;
156 	itt_t	 itt;	/* Initiator Task Tag */
157 	__be32 data_length;
158 	__be32 cmdsn;
159 	__be32 exp_statsn;
160 	uint8_t cdb[ISCSI_CDB_SIZE];	/* SCSI Command Block */
161 	/* Additional Data (Command Dependent) */
162 };
163 
164 /* Command PDU flags */
165 #define ISCSI_FLAG_CMD_FINAL		0x80
166 #define ISCSI_FLAG_CMD_READ		0x40
167 #define ISCSI_FLAG_CMD_WRITE		0x20
168 #define ISCSI_FLAG_CMD_ATTR_MASK	0x07	/* 3 bits */
169 
170 /* SCSI Command Attribute values */
171 #define ISCSI_ATTR_UNTAGGED		0
172 #define ISCSI_ATTR_SIMPLE		1
173 #define ISCSI_ATTR_ORDERED		2
174 #define ISCSI_ATTR_HEAD_OF_QUEUE	3
175 #define ISCSI_ATTR_ACA			4
176 
177 struct iscsi_rlength_ahdr {
178 	__be16 ahslength;
179 	uint8_t ahstype;
180 	uint8_t reserved;
181 	__be32 read_length;
182 };
183 
184 /* Extended CDB AHS */
185 struct iscsi_ecdb_ahdr {
186 	__be16 ahslength;	/* CDB length - 15, including reserved byte */
187 	uint8_t ahstype;
188 	uint8_t reserved;
189 	/* 4-byte aligned extended CDB spillover */
190 	uint8_t ecdb[SCSI_MAX_VARLEN_CDB_SIZE - ISCSI_CDB_SIZE];
191 };
192 
193 /* SCSI Response Header */
194 struct iscsi_scsi_rsp {
195 	uint8_t opcode;
196 	uint8_t flags;
197 	uint8_t response;
198 	uint8_t cmd_status;
199 	uint8_t hlength;
200 	uint8_t dlength[3];
201 	uint8_t rsvd[8];
202 	itt_t	 itt;	/* Initiator Task Tag */
203 	__be32	rsvd1;
204 	__be32	statsn;
205 	__be32	exp_cmdsn;
206 	__be32	max_cmdsn;
207 	__be32	exp_datasn;
208 	__be32	bi_residual_count;
209 	__be32	residual_count;
210 	/* Response or Sense Data (optional) */
211 };
212 
213 /* Command Response PDU flags */
214 #define ISCSI_FLAG_CMD_BIDI_OVERFLOW	0x10
215 #define ISCSI_FLAG_CMD_BIDI_UNDERFLOW	0x08
216 #define ISCSI_FLAG_CMD_OVERFLOW		0x04
217 #define ISCSI_FLAG_CMD_UNDERFLOW	0x02
218 
219 /* iSCSI Status values. Valid if Rsp Selector bit is not set */
220 #define ISCSI_STATUS_CMD_COMPLETED	0
221 #define ISCSI_STATUS_TARGET_FAILURE	1
222 #define ISCSI_STATUS_SUBSYS_FAILURE	2
223 
224 /* Asynchronous Event Header */
225 struct iscsi_async {
226 	uint8_t opcode;
227 	uint8_t flags;
228 	uint8_t rsvd2[2];
229 	uint8_t rsvd3;
230 	uint8_t dlength[3];
231 	struct scsi_lun	lun;
232 	uint8_t rsvd4[8];
233 	__be32	statsn;
234 	__be32	exp_cmdsn;
235 	__be32	max_cmdsn;
236 	uint8_t async_event;
237 	uint8_t async_vcode;
238 	__be16	param1;
239 	__be16	param2;
240 	__be16	param3;
241 	uint8_t rsvd5[4];
242 };
243 
244 /* iSCSI Event Codes */
245 #define ISCSI_ASYNC_MSG_SCSI_EVENT			0
246 #define ISCSI_ASYNC_MSG_REQUEST_LOGOUT			1
247 #define ISCSI_ASYNC_MSG_DROPPING_CONNECTION		2
248 #define ISCSI_ASYNC_MSG_DROPPING_ALL_CONNECTIONS	3
249 #define ISCSI_ASYNC_MSG_PARAM_NEGOTIATION		4
250 #define ISCSI_ASYNC_MSG_VENDOR_SPECIFIC			255
251 
252 /* NOP-Out Message */
253 struct iscsi_nopout {
254 	uint8_t opcode;
255 	uint8_t flags;
256 	__be16	rsvd2;
257 	uint8_t rsvd3;
258 	uint8_t dlength[3];
259 	struct scsi_lun	lun;
260 	itt_t	 itt;	/* Initiator Task Tag */
261 	__be32	ttt;	/* Target Transfer Tag */
262 	__be32	cmdsn;
263 	__be32	exp_statsn;
264 	uint8_t rsvd4[16];
265 };
266 
267 /* NOP-In Message */
268 struct iscsi_nopin {
269 	uint8_t opcode;
270 	uint8_t flags;
271 	__be16	rsvd2;
272 	uint8_t rsvd3;
273 	uint8_t dlength[3];
274 	struct scsi_lun	lun;
275 	itt_t	 itt;	/* Initiator Task Tag */
276 	__be32	ttt;	/* Target Transfer Tag */
277 	__be32	statsn;
278 	__be32	exp_cmdsn;
279 	__be32	max_cmdsn;
280 	uint8_t rsvd4[12];
281 };
282 
283 /* SCSI Task Management Message Header */
284 struct iscsi_tm {
285 	uint8_t opcode;
286 	uint8_t flags;
287 	uint8_t rsvd1[2];
288 	uint8_t hlength;
289 	uint8_t dlength[3];
290 	struct scsi_lun lun;
291 	itt_t	 itt;	/* Initiator Task Tag */
292 	itt_t	 rtt;	/* Reference Task Tag */
293 	__be32	cmdsn;
294 	__be32	exp_statsn;
295 	__be32	refcmdsn;
296 	__be32	exp_datasn;
297 	uint8_t rsvd2[8];
298 };
299 
300 #define ISCSI_FLAG_TM_FUNC_MASK			0x7F
301 
302 /* Function values */
303 #define ISCSI_TM_FUNC_ABORT_TASK		1
304 #define ISCSI_TM_FUNC_ABORT_TASK_SET		2
305 #define ISCSI_TM_FUNC_CLEAR_ACA			3
306 #define ISCSI_TM_FUNC_CLEAR_TASK_SET		4
307 #define ISCSI_TM_FUNC_LOGICAL_UNIT_RESET	5
308 #define ISCSI_TM_FUNC_TARGET_WARM_RESET		6
309 #define ISCSI_TM_FUNC_TARGET_COLD_RESET		7
310 #define ISCSI_TM_FUNC_TASK_REASSIGN		8
311 
312 #define ISCSI_TM_FUNC_VALUE(hdr) ((hdr)->flags & ISCSI_FLAG_TM_FUNC_MASK)
313 
314 /* SCSI Task Management Response Header */
315 struct iscsi_tm_rsp {
316 	uint8_t opcode;
317 	uint8_t flags;
318 	uint8_t response;	/* see Response values below */
319 	uint8_t qualifier;
320 	uint8_t hlength;
321 	uint8_t dlength[3];
322 	uint8_t rsvd2[8];
323 	itt_t	 itt;	/* Initiator Task Tag */
324 	itt_t	 rtt;	/* Reference Task Tag */
325 	__be32	statsn;
326 	__be32	exp_cmdsn;
327 	__be32	max_cmdsn;
328 	uint8_t rsvd3[12];
329 };
330 
331 /* Response values */
332 #define ISCSI_TMF_RSP_COMPLETE		0x00
333 #define ISCSI_TMF_RSP_NO_TASK		0x01
334 #define ISCSI_TMF_RSP_NO_LUN		0x02
335 #define ISCSI_TMF_RSP_TASK_ALLEGIANT	0x03
336 #define ISCSI_TMF_RSP_NO_FAILOVER	0x04
337 #define ISCSI_TMF_RSP_NOT_SUPPORTED	0x05
338 #define ISCSI_TMF_RSP_AUTH_FAILED	0x06
339 #define ISCSI_TMF_RSP_REJECTED		0xff
340 
341 /* Ready To Transfer Header */
342 struct iscsi_r2t_rsp {
343 	uint8_t opcode;
344 	uint8_t flags;
345 	uint8_t rsvd2[2];
346 	uint8_t	hlength;
347 	uint8_t	dlength[3];
348 	struct scsi_lun	lun;
349 	itt_t	 itt;	/* Initiator Task Tag */
350 	__be32	ttt;	/* Target Transfer Tag */
351 	__be32	statsn;
352 	__be32	exp_cmdsn;
353 	__be32	max_cmdsn;
354 	__be32	r2tsn;
355 	__be32	data_offset;
356 	__be32	data_length;
357 };
358 
359 /* SCSI Data Hdr */
360 struct iscsi_data {
361 	uint8_t opcode;
362 	uint8_t flags;
363 	uint8_t rsvd2[2];
364 	uint8_t rsvd3;
365 	uint8_t dlength[3];
366 	struct scsi_lun lun;
367 	itt_t	 itt;
368 	__be32	ttt;
369 	__be32	rsvd4;
370 	__be32	exp_statsn;
371 	__be32	rsvd5;
372 	__be32	datasn;
373 	__be32	offset;
374 	__be32	rsvd6;
375 	/* Payload */
376 };
377 
378 /* SCSI Data Response Hdr */
379 struct iscsi_data_rsp {
380 	uint8_t opcode;
381 	uint8_t flags;
382 	uint8_t rsvd2;
383 	uint8_t cmd_status;
384 	uint8_t hlength;
385 	uint8_t dlength[3];
386 	struct scsi_lun	lun;
387 	itt_t	 itt;
388 	__be32	ttt;
389 	__be32	statsn;
390 	__be32	exp_cmdsn;
391 	__be32	max_cmdsn;
392 	__be32	datasn;
393 	__be32	offset;
394 	__be32	residual_count;
395 };
396 
397 /* Data Response PDU flags */
398 #define ISCSI_FLAG_DATA_ACK		0x40
399 #define ISCSI_FLAG_DATA_OVERFLOW	0x04
400 #define ISCSI_FLAG_DATA_UNDERFLOW	0x02
401 #define ISCSI_FLAG_DATA_STATUS		0x01
402 
403 /* Text Header */
404 struct iscsi_text {
405 	uint8_t opcode;
406 	uint8_t flags;
407 	uint8_t rsvd2[2];
408 	uint8_t hlength;
409 	uint8_t dlength[3];
410 	uint8_t rsvd4[8];
411 	itt_t	 itt;
412 	__be32	ttt;
413 	__be32	cmdsn;
414 	__be32	exp_statsn;
415 	uint8_t rsvd5[16];
416 	/* Text - key=value pairs */
417 };
418 
419 #define ISCSI_FLAG_TEXT_CONTINUE	0x40
420 
421 /* Text Response Header */
422 struct iscsi_text_rsp {
423 	uint8_t opcode;
424 	uint8_t flags;
425 	uint8_t rsvd2[2];
426 	uint8_t hlength;
427 	uint8_t dlength[3];
428 	uint8_t rsvd4[8];
429 	itt_t	 itt;
430 	__be32	ttt;
431 	__be32	statsn;
432 	__be32	exp_cmdsn;
433 	__be32	max_cmdsn;
434 	uint8_t rsvd5[12];
435 	/* Text Response - key:value pairs */
436 };
437 
438 /* Login Header */
439 struct iscsi_login_req {
440 	uint8_t opcode;
441 	uint8_t flags;
442 	uint8_t max_version;	/* Max. version supported */
443 	uint8_t min_version;	/* Min. version supported */
444 	uint8_t hlength;
445 	uint8_t dlength[3];
446 	uint8_t isid[6];	/* Initiator Session ID */
447 	__be16	tsih;	/* Target Session Handle */
448 	itt_t	 itt;	/* Initiator Task Tag */
449 	__be16	cid;
450 	__be16	rsvd3;
451 	__be32	cmdsn;
452 	__be32	exp_statsn;
453 	uint8_t rsvd5[16];
454 };
455 
456 /* Login PDU flags */
457 #define ISCSI_FLAG_LOGIN_TRANSIT		0x80
458 #define ISCSI_FLAG_LOGIN_CONTINUE		0x40
459 #define ISCSI_FLAG_LOGIN_CURRENT_STAGE_MASK	0x0C	/* 2 bits */
460 #define ISCSI_FLAG_LOGIN_CURRENT_STAGE1		0x04
461 #define ISCSI_FLAG_LOGIN_CURRENT_STAGE2		0x08
462 #define ISCSI_FLAG_LOGIN_CURRENT_STAGE3		0x0C
463 #define ISCSI_FLAG_LOGIN_NEXT_STAGE_MASK	0x03	/* 2 bits */
464 #define ISCSI_FLAG_LOGIN_NEXT_STAGE1		0x01
465 #define ISCSI_FLAG_LOGIN_NEXT_STAGE2		0x02
466 #define ISCSI_FLAG_LOGIN_NEXT_STAGE3		0x03
467 
468 #define ISCSI_LOGIN_CURRENT_STAGE(flags) \
469 	((flags & ISCSI_FLAG_LOGIN_CURRENT_STAGE_MASK) >> 2)
470 #define ISCSI_LOGIN_NEXT_STAGE(flags) \
471 	(flags & ISCSI_FLAG_LOGIN_NEXT_STAGE_MASK)
472 
473 /* Login Response Header */
474 struct iscsi_login_rsp {
475 	uint8_t opcode;
476 	uint8_t flags;
477 	uint8_t max_version;	/* Max. version supported */
478 	uint8_t active_version;	/* Active version */
479 	uint8_t hlength;
480 	uint8_t dlength[3];
481 	uint8_t isid[6];	/* Initiator Session ID */
482 	__be16	tsih;	/* Target Session Handle */
483 	itt_t	 itt;	/* Initiator Task Tag */
484 	__be32	rsvd3;
485 	__be32	statsn;
486 	__be32	exp_cmdsn;
487 	__be32	max_cmdsn;
488 	uint8_t status_class;	/* see Login RSP ststus classes below */
489 	uint8_t status_detail;	/* see Login RSP Status details below */
490 	uint8_t rsvd4[10];
491 };
492 
493 /* Login stage (phase) codes for CSG, NSG */
494 #define ISCSI_INITIAL_LOGIN_STAGE		-1
495 #define ISCSI_SECURITY_NEGOTIATION_STAGE	0
496 #define ISCSI_OP_PARMS_NEGOTIATION_STAGE	1
497 #define ISCSI_FULL_FEATURE_PHASE		3
498 
499 /* Login Status response classes */
500 #define ISCSI_STATUS_CLS_SUCCESS		0x00
501 #define ISCSI_STATUS_CLS_REDIRECT		0x01
502 #define ISCSI_STATUS_CLS_INITIATOR_ERR		0x02
503 #define ISCSI_STATUS_CLS_TARGET_ERR		0x03
504 
505 /* Login Status response detail codes */
506 /* Class-0 (Success) */
507 #define ISCSI_LOGIN_STATUS_ACCEPT		0x00
508 
509 /* Class-1 (Redirection) */
510 #define ISCSI_LOGIN_STATUS_TGT_MOVED_TEMP	0x01
511 #define ISCSI_LOGIN_STATUS_TGT_MOVED_PERM	0x02
512 
513 /* Class-2 (Initiator Error) */
514 #define ISCSI_LOGIN_STATUS_INIT_ERR		0x00
515 #define ISCSI_LOGIN_STATUS_AUTH_FAILED		0x01
516 #define ISCSI_LOGIN_STATUS_TGT_FORBIDDEN	0x02
517 #define ISCSI_LOGIN_STATUS_TGT_NOT_FOUND	0x03
518 #define ISCSI_LOGIN_STATUS_TGT_REMOVED		0x04
519 #define ISCSI_LOGIN_STATUS_NO_VERSION		0x05
520 #define ISCSI_LOGIN_STATUS_ISID_ERROR		0x06
521 #define ISCSI_LOGIN_STATUS_MISSING_FIELDS	0x07
522 #define ISCSI_LOGIN_STATUS_CONN_ADD_FAILED	0x08
523 #define ISCSI_LOGIN_STATUS_NO_SESSION_TYPE	0x09
524 #define ISCSI_LOGIN_STATUS_NO_SESSION		0x0a
525 #define ISCSI_LOGIN_STATUS_INVALID_REQUEST	0x0b
526 
527 /* Class-3 (Target Error) */
528 #define ISCSI_LOGIN_STATUS_TARGET_ERROR		0x00
529 #define ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE	0x01
530 #define ISCSI_LOGIN_STATUS_NO_RESOURCES		0x02
531 
532 /* Logout Header */
533 struct iscsi_logout {
534 	uint8_t opcode;
535 	uint8_t flags;
536 	uint8_t rsvd1[2];
537 	uint8_t hlength;
538 	uint8_t dlength[3];
539 	uint8_t rsvd2[8];
540 	itt_t	 itt;	/* Initiator Task Tag */
541 	__be16	cid;
542 	uint8_t rsvd3[2];
543 	__be32	cmdsn;
544 	__be32	exp_statsn;
545 	uint8_t rsvd4[16];
546 };
547 
548 /* Logout PDU flags */
549 #define ISCSI_FLAG_LOGOUT_REASON_MASK	0x7F
550 
551 /* logout reason_code values */
552 
553 #define ISCSI_LOGOUT_REASON_CLOSE_SESSION	0
554 #define ISCSI_LOGOUT_REASON_CLOSE_CONNECTION	1
555 #define ISCSI_LOGOUT_REASON_RECOVERY		2
556 #define ISCSI_LOGOUT_REASON_AEN_REQUEST		3
557 
558 /* Logout Response Header */
559 struct iscsi_logout_rsp {
560 	uint8_t opcode;
561 	uint8_t flags;
562 	uint8_t response;	/* see Logout response values below */
563 	uint8_t rsvd2;
564 	uint8_t hlength;
565 	uint8_t dlength[3];
566 	uint8_t rsvd3[8];
567 	itt_t	 itt;	/* Initiator Task Tag */
568 	__be32	rsvd4;
569 	__be32	statsn;
570 	__be32	exp_cmdsn;
571 	__be32	max_cmdsn;
572 	__be32	rsvd5;
573 	__be16	t2wait;
574 	__be16	t2retain;
575 	__be32	rsvd6;
576 };
577 
578 /* logout response status values */
579 
580 #define ISCSI_LOGOUT_SUCCESS			0
581 #define ISCSI_LOGOUT_CID_NOT_FOUND		1
582 #define ISCSI_LOGOUT_RECOVERY_UNSUPPORTED	2
583 #define ISCSI_LOGOUT_CLEANUP_FAILED		3
584 
585 /* SNACK Header */
586 struct iscsi_snack {
587 	uint8_t opcode;
588 	uint8_t flags;
589 	uint8_t rsvd2[2];
590 	uint8_t hlength;
591 	uint8_t dlength[3];
592 	uint8_t lun[8];
593 	itt_t	 itt;
594 	__be32  ttt;
595 	uint8_t rsvd3[4];
596 	__be32  exp_statsn;
597 	uint8_t rsvd4[8];
598 	__be32	begrun;
599 	__be32	runlength;
600 };
601 
602 /* SNACK PDU flags */
603 #define ISCSI_FLAG_SNACK_TYPE_DATA		0
604 #define ISCSI_FLAG_SNACK_TYPE_R2T		0
605 #define ISCSI_FLAG_SNACK_TYPE_STATUS		1
606 #define ISCSI_FLAG_SNACK_TYPE_DATA_ACK		2
607 #define ISCSI_FLAG_SNACK_TYPE_RDATA		3
608 #define ISCSI_FLAG_SNACK_TYPE_MASK	0x0F	/* 4 bits */
609 
610 /* Reject Message Header */
611 struct iscsi_reject {
612 	uint8_t opcode;
613 	uint8_t flags;
614 	uint8_t reason;
615 	uint8_t rsvd2;
616 	uint8_t hlength;
617 	uint8_t dlength[3];
618 	uint8_t rsvd3[8];
619 	__be32  ffffffff;
620 	uint8_t rsvd4[4];
621 	__be32	statsn;
622 	__be32	exp_cmdsn;
623 	__be32	max_cmdsn;
624 	__be32	datasn;
625 	uint8_t rsvd5[8];
626 	/* Text - Rejected hdr */
627 };
628 
629 /* Reason for Reject */
630 #define ISCSI_REASON_CMD_BEFORE_LOGIN	1
631 #define ISCSI_REASON_DATA_DIGEST_ERROR	2
632 #define ISCSI_REASON_DATA_SNACK_REJECT	3
633 #define ISCSI_REASON_PROTOCOL_ERROR	4
634 #define ISCSI_REASON_CMD_NOT_SUPPORTED	5
635 #define ISCSI_REASON_IMM_CMD_REJECT		6
636 #define ISCSI_REASON_TASK_IN_PROGRESS	7
637 #define ISCSI_REASON_INVALID_SNACK		8
638 #define ISCSI_REASON_BOOKMARK_INVALID	9
639 #define ISCSI_REASON_BOOKMARK_NO_RESOURCES	10
640 #define ISCSI_REASON_NEGOTIATION_RESET	11
641 
642 /* Max. number of Key=Value pairs in a text message */
643 #define MAX_KEY_VALUE_PAIRS	8192
644 
645 /* maximum length for text keys/values */
646 #define KEY_MAXLEN		64
647 #define VALUE_MAXLEN		255
648 #define TARGET_NAME_MAXLEN	VALUE_MAXLEN
649 
650 #define ISCSI_DEF_MAX_RECV_SEG_LEN		8192
651 #define ISCSI_MIN_MAX_RECV_SEG_LEN		512
652 #define ISCSI_MAX_MAX_RECV_SEG_LEN		16777215
653 
654 #define ISCSI_DEF_FIRST_BURST_LEN		65536
655 #define ISCSI_MIN_FIRST_BURST_LEN		512
656 #define ISCSI_MAX_FIRST_BURST_LEN		16777215
657 
658 #define ISCSI_DEF_MAX_BURST_LEN			262144
659 #define ISCSI_MIN_MAX_BURST_LEN			512
660 #define ISCSI_MAX_MAX_BURST_LEN			16777215
661 
662 #define ISCSI_DEF_TIME2WAIT			2
663 
664 /************************* RFC 3720 End *****************************/
665 
666 #endif /* ISCSI_PROTO_H */
667