xref: /spdk/lib/iscsi/param.c (revision 4c6c794be3caa0668b1019e1371f1c0e4a0c7e7a)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright (C) 2008-2012 Daisuke Aoyama <aoyama@peach.ne.jp>.
5  *   Copyright (c) Intel Corporation.
6  *   All rights reserved.
7  *
8  *   Redistribution and use in source and binary forms, with or without
9  *   modification, are permitted provided that the following conditions
10  *   are met:
11  *
12  *     * Redistributions of source code must retain the above copyright
13  *       notice, this list of conditions and the following disclaimer.
14  *     * Redistributions in binary form must reproduce the above copyright
15  *       notice, this list of conditions and the following disclaimer in
16  *       the documentation and/or other materials provided with the
17  *       distribution.
18  *     * Neither the name of Intel Corporation nor the names of its
19  *       contributors may be used to endorse or promote products derived
20  *       from this software without specific prior written permission.
21  *
22  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
25  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
26  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
27  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
28  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
32  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 #include "spdk/stdinc.h"
36 
37 #include "spdk/string.h"
38 #include "iscsi/iscsi.h"
39 #include "iscsi/param.h"
40 #include "iscsi/conn.h"
41 #include "spdk/string.h"
42 
43 #include "spdk/log.h"
44 
45 #define MAX_TMPBUF 1024
46 
47 /* whose value may be bigger than 255 */
48 static const char *non_simple_value_params[] = {
49 	"CHAP_C",
50 	"CHAP_R",
51 	NULL,
52 };
53 
54 void
55 iscsi_param_free(struct iscsi_param *params)
56 {
57 	struct iscsi_param *param, *next_param;
58 
59 	if (params == NULL) {
60 		return;
61 	}
62 	for (param = params; param != NULL; param = next_param) {
63 		next_param = param->next;
64 		if (param->list) {
65 			free(param->list);
66 		}
67 		free(param->val);
68 		free(param->key);
69 		free(param);
70 	}
71 }
72 
73 static int
74 iscsi_find_key_in_array(const char *key, const char *array[])
75 {
76 	int i;
77 
78 	for (i = 0; array[i] != NULL; i++) {
79 		if (strcasecmp(key, array[i]) == 0) {
80 			return 1;
81 		}
82 	}
83 	return 0;
84 }
85 
86 struct iscsi_param *
87 iscsi_param_find(struct iscsi_param *params, const char *key)
88 {
89 	struct iscsi_param *param;
90 
91 	if (params == NULL || key == NULL) {
92 		return NULL;
93 	}
94 	for (param = params; param != NULL; param = param->next) {
95 		if (param->key != NULL && param->key[0] == key[0]
96 		    && strcasecmp(param->key, key) == 0) {
97 			return param;
98 		}
99 	}
100 	return NULL;
101 }
102 
103 int
104 iscsi_param_del(struct iscsi_param **params, const char *key)
105 {
106 	struct iscsi_param *param, *prev_param = NULL;
107 
108 	SPDK_DEBUGLOG(iscsi, "del %s\n", key);
109 	if (params == NULL || key == NULL) {
110 		return 0;
111 	}
112 	for (param = *params; param != NULL; param = param->next) {
113 		if (param->key != NULL && param->key[0] == key[0]
114 		    && strcasecmp(param->key, key) == 0) {
115 			if (prev_param != NULL) {
116 				prev_param->next = param->next;
117 			} else {
118 				*params = param->next;
119 			}
120 			param->next = NULL;
121 			iscsi_param_free(param);
122 			return 0;
123 		}
124 		prev_param = param;
125 	}
126 	return -1;
127 }
128 
129 int
130 iscsi_param_add(struct iscsi_param **params, const char *key,
131 		const char *val, const char *list, int type)
132 {
133 	struct iscsi_param *param, *last_param;
134 
135 	SPDK_DEBUGLOG(iscsi, "add %s=%s, list=[%s], type=%d\n",
136 		      key, val, list, type);
137 	if (key == NULL) {
138 		return -1;
139 	}
140 
141 	param = iscsi_param_find(*params, key);
142 	if (param != NULL) {
143 		iscsi_param_del(params, key);
144 	}
145 
146 	param = calloc(1, sizeof(*param));
147 	if (!param) {
148 		SPDK_ERRLOG("calloc() failed for parameter\n");
149 		return -ENOMEM;
150 	}
151 
152 	param->next = NULL;
153 	param->key = xstrdup(key);
154 	param->val = xstrdup(val);
155 	param->list = xstrdup(list);
156 	param->type = type;
157 
158 	last_param = *params;
159 	if (last_param != NULL) {
160 		while (last_param->next != NULL) {
161 			last_param = last_param->next;
162 		}
163 		last_param->next = param;
164 	} else {
165 		*params = param;
166 	}
167 
168 	return 0;
169 }
170 
171 int
172 iscsi_param_set(struct iscsi_param *params, const char *key,
173 		const char *val)
174 {
175 	struct iscsi_param *param;
176 
177 	SPDK_DEBUGLOG(iscsi, "set %s=%s\n", key, val);
178 	param = iscsi_param_find(params, key);
179 	if (param == NULL) {
180 		SPDK_ERRLOG("no key %s\n", key);
181 		return -1;
182 	}
183 
184 	free(param->val);
185 
186 	param->val = xstrdup(val);
187 
188 	return 0;
189 }
190 
191 int
192 iscsi_param_set_int(struct iscsi_param *params, const char *key, uint32_t val)
193 {
194 	char buf[MAX_TMPBUF];
195 	struct iscsi_param *param;
196 
197 	SPDK_DEBUGLOG(iscsi, "set %s=%d\n", key, val);
198 	param = iscsi_param_find(params, key);
199 	if (param == NULL) {
200 		SPDK_ERRLOG("no key %s\n", key);
201 		return -1;
202 	}
203 
204 	free(param->val);
205 	snprintf(buf, sizeof buf, "%d", val);
206 
207 	param->val = strdup(buf);
208 
209 	return 0;
210 }
211 
212 /**
213  * Parse a single KEY=VAL pair
214  *
215  * data = "KEY=VAL<NUL>"
216  */
217 static int
218 iscsi_parse_param(struct iscsi_param **params, const uint8_t *data, uint32_t data_len)
219 {
220 	int rc;
221 	uint8_t *key_copy, *val_copy;
222 	const uint8_t *key_end;
223 	int key_len, val_len;
224 	int max_len;
225 
226 	data_len = strnlen(data, data_len);
227 	/* No such thing as strnchr so use memchr instead. */
228 	key_end = memchr(data, '=', data_len);
229 	if (!key_end) {
230 		SPDK_ERRLOG("'=' not found\n");
231 		return -1;
232 	}
233 
234 	key_len = key_end - data;
235 	if (key_len == 0) {
236 		SPDK_ERRLOG("Empty key\n");
237 		return -1;
238 	}
239 	/*
240 	 * RFC 7143 6.1
241 	 */
242 	if (key_len > ISCSI_TEXT_MAX_KEY_LEN) {
243 		SPDK_ERRLOG("Key name length is bigger than 63\n");
244 		return -1;
245 	}
246 
247 	key_copy = malloc(key_len + 1);
248 	if (!key_copy) {
249 		SPDK_ERRLOG("malloc() failed for key_copy\n");
250 		return -ENOMEM;
251 	}
252 
253 	memcpy(key_copy, data, key_len);
254 	key_copy[key_len] = '\0';
255 	/* check whether this key is duplicated */
256 	if (NULL != iscsi_param_find(*params, key_copy)) {
257 		SPDK_ERRLOG("Duplicated Key %s\n", key_copy);
258 		free(key_copy);
259 		return -1;
260 	}
261 
262 	val_len = strnlen(key_end + 1, data_len - key_len - 1);
263 	/*
264 	 * RFC 3720 5.1
265 	 * If not otherwise specified, the maximum length of a simple-value
266 	 * (not its encoded representation) is 255 bytes, not including the delimiter
267 	 * (comma or zero byte).
268 	 */
269 	/*
270 	 * comma or zero is counted in, otherwise we need to iterate each parameter
271 	 * value
272 	 */
273 	max_len = iscsi_find_key_in_array(key_copy, non_simple_value_params) ?
274 		  ISCSI_TEXT_MAX_VAL_LEN : ISCSI_TEXT_MAX_SIMPLE_VAL_LEN;
275 	if (val_len > max_len) {
276 		SPDK_ERRLOG("Overflow Val %d\n", val_len);
277 		free(key_copy);
278 		return -1;
279 	}
280 
281 	val_copy = calloc(1, val_len + 1);
282 	if (val_copy == NULL) {
283 		SPDK_ERRLOG("Could not allocate value string\n");
284 		free(key_copy);
285 		return -1;
286 	}
287 
288 	memcpy(val_copy, key_end + 1, val_len);
289 
290 	rc = iscsi_param_add(params, key_copy, val_copy, NULL, 0);
291 	free(val_copy);
292 	free(key_copy);
293 	if (rc < 0) {
294 		SPDK_ERRLOG("iscsi_param_add() failed\n");
295 		return -1;
296 	}
297 
298 	/* return number of bytes consumed
299 	 * +1 for '=' and +1 for NUL
300 	 */
301 	return key_len + 1 + val_len + 1;
302 }
303 
304 /**
305  * Parse a sequence of KEY=VAL pairs.
306  *
307  * \param data "KEY=VAL<NUL>KEY=VAL<NUL>..."
308  * \param len length of data in bytes
309  */
310 int
311 iscsi_parse_params(struct iscsi_param **params, const uint8_t *data,
312 		   int len, bool cbit_enabled, char **partial_parameter)
313 {
314 	int rc, offset = 0;
315 	char *p;
316 	int i;
317 
318 	/* Spec does not disallow TEXT PDUs with zero length, just return
319 	 * immediately in that case, since there is no param data to parse
320 	 * and any existing partial parameter would remain as-is.
321 	 */
322 	if (len == 0) {
323 		return 0;
324 	}
325 
326 	assert(data != NULL);
327 
328 	/* strip the partial text parameters if previous PDU have C enabled */
329 	if (partial_parameter && *partial_parameter) {
330 		for (i = 0; i < len && data[i] != '\0'; i++) {
331 			;
332 		}
333 		p = spdk_sprintf_alloc("%s%s", *partial_parameter, (const char *)data);
334 		if (!p) {
335 			return -1;
336 		}
337 		rc = iscsi_parse_param(params, p, i + strlen(*partial_parameter));
338 		free(p);
339 		if (rc < 0) {
340 			return -1;
341 		}
342 		free(*partial_parameter);
343 		*partial_parameter = NULL;
344 
345 		data = data + i + 1;
346 		len = len - (i + 1);
347 	}
348 
349 	/* strip the partial text parameters if C bit is enabled */
350 	if (cbit_enabled) {
351 		if (partial_parameter == NULL) {
352 			SPDK_ERRLOG("C bit set but no partial parameters provided\n");
353 			return -1;
354 		}
355 
356 		/*
357 		 * reverse iterate the string from the tail not including '\0'
358 		 */
359 		for (i = len - 1; data[i] != '\0' && i > 0; i--) {
360 			;
361 		}
362 		if (i != 0) {
363 			/* We found a NULL character - don't copy it into the
364 			 * partial parameter.
365 			 */
366 			i++;
367 		}
368 
369 		*partial_parameter = calloc(1, len - i + 1);
370 		if (*partial_parameter == NULL) {
371 			SPDK_ERRLOG("could not allocate partial parameter\n");
372 			return -1;
373 		}
374 		memcpy(*partial_parameter, &data[i], len - i);
375 		if (i == 0) {
376 			/* No full parameters to parse - so return now. */
377 			return 0;
378 		} else {
379 			len = i - 1;
380 		}
381 	}
382 
383 	while (offset < len && data[offset] != '\0') {
384 		rc = iscsi_parse_param(params, data + offset, len - offset);
385 		if (rc < 0) {
386 			return -1;
387 		}
388 		offset += rc;
389 	}
390 	return 0;
391 }
392 
393 char *
394 iscsi_param_get_val(struct iscsi_param *params, const char *key)
395 {
396 	struct iscsi_param *param;
397 
398 	param = iscsi_param_find(params, key);
399 	if (param == NULL) {
400 		return NULL;
401 	}
402 	return param->val;
403 }
404 
405 int
406 iscsi_param_eq_val(struct iscsi_param *params, const char *key,
407 		   const char *val)
408 {
409 	struct iscsi_param *param;
410 
411 	param = iscsi_param_find(params, key);
412 	if (param == NULL) {
413 		return 0;
414 	}
415 	if (strcasecmp(param->val, val) == 0) {
416 		return 1;
417 	}
418 	return 0;
419 }
420 
421 struct iscsi_param_table {
422 	const char *key;
423 	const char *val;
424 	const char *list;
425 	int type;
426 };
427 
428 static const struct iscsi_param_table conn_param_table[] = {
429 	{ "HeaderDigest", "None", "CRC32C,None", ISPT_LIST },
430 	{ "DataDigest", "None", "CRC32C,None", ISPT_LIST },
431 	{ "MaxRecvDataSegmentLength", "8192", "512,16777215", ISPT_NUMERICAL_DECLARATIVE },
432 	{ "OFMarker", "No", "Yes,No", ISPT_BOOLEAN_AND },
433 	{ "IFMarker", "No", "Yes,No", ISPT_BOOLEAN_AND },
434 	{ "OFMarkInt", "1", "1,65535", ISPT_NUMERICAL_MIN },
435 	{ "IFMarkInt", "1", "1,65535", ISPT_NUMERICAL_MIN },
436 	{ "AuthMethod", "None", "CHAP,None", ISPT_LIST },
437 	{ "CHAP_A", "5", "5", ISPT_LIST },
438 	{ "CHAP_N", "", "", ISPT_DECLARATIVE },
439 	{ "CHAP_R", "", "", ISPT_DECLARATIVE },
440 	{ "CHAP_I", "", "", ISPT_DECLARATIVE },
441 	{ "CHAP_C", "", "", ISPT_DECLARATIVE },
442 	{ NULL, NULL, NULL, ISPT_INVALID },
443 };
444 
445 static const struct iscsi_param_table sess_param_table[] = {
446 	{ "MaxConnections", "1", "1,65535", ISPT_NUMERICAL_MIN },
447 #if 0
448 	/* need special handling */
449 	{ "SendTargets", "", "", ISPT_DECLARATIVE },
450 #endif
451 	{ "TargetName", "", "", ISPT_DECLARATIVE },
452 	{ "InitiatorName", "", "", ISPT_DECLARATIVE },
453 	{ "TargetAlias", "", "", ISPT_DECLARATIVE },
454 	{ "InitiatorAlias", "", "", ISPT_DECLARATIVE },
455 	{ "TargetAddress", "", "", ISPT_DECLARATIVE },
456 	{ "TargetPortalGroupTag", "1", "1,65535", ISPT_NUMERICAL_DECLARATIVE },
457 	{ "InitialR2T", "Yes", "Yes,No", ISPT_BOOLEAN_OR },
458 	{ "ImmediateData", "Yes", "Yes,No", ISPT_BOOLEAN_AND },
459 	{ "MaxBurstLength", "262144", "512,16777215", ISPT_NUMERICAL_MIN },
460 	{ "FirstBurstLength", "65536", "512,16777215", ISPT_NUMERICAL_MIN },
461 	{ "DefaultTime2Wait", "2", "0,3600", ISPT_NUMERICAL_MAX },
462 	{ "DefaultTime2Retain", "20", "0,3600", ISPT_NUMERICAL_MIN },
463 	{ "MaxOutstandingR2T", "1", "1,65536", ISPT_NUMERICAL_MIN },
464 	{ "DataPDUInOrder", "Yes", "Yes,No", ISPT_BOOLEAN_OR },
465 	{ "DataSequenceInOrder", "Yes", "Yes,No", ISPT_BOOLEAN_OR },
466 	{ "ErrorRecoveryLevel", "0", "0,2", ISPT_NUMERICAL_MIN },
467 	{ "SessionType", "Normal", "Normal,Discovery", ISPT_DECLARATIVE },
468 	{ NULL, NULL, NULL, ISPT_INVALID },
469 };
470 
471 static int
472 iscsi_params_init_internal(struct iscsi_param **params,
473 			   const struct iscsi_param_table *table)
474 {
475 	int rc;
476 	int i;
477 	struct iscsi_param *param;
478 
479 	for (i = 0; table[i].key != NULL; i++) {
480 		rc = iscsi_param_add(params, table[i].key, table[i].val,
481 				     table[i].list, table[i].type);
482 		if (rc < 0) {
483 			SPDK_ERRLOG("iscsi_param_add() failed\n");
484 			return -1;
485 		}
486 		param = iscsi_param_find(*params, table[i].key);
487 		if (param != NULL) {
488 			param->state_index = i;
489 		} else {
490 			SPDK_ERRLOG("iscsi_param_find() failed\n");
491 			return -1;
492 		}
493 	}
494 
495 	return 0;
496 }
497 
498 int
499 iscsi_conn_params_init(struct iscsi_param **params)
500 {
501 	return iscsi_params_init_internal(params, &conn_param_table[0]);
502 }
503 
504 int
505 iscsi_sess_params_init(struct iscsi_param **params)
506 {
507 	return iscsi_params_init_internal(params, &sess_param_table[0]);
508 }
509 
510 static const char *chap_type[] = {
511 	"CHAP_A",
512 	"CHAP_N",
513 	"CHAP_R",
514 	"CHAP_I",
515 	"CHAP_C",
516 	NULL,
517 };
518 
519 static const char *discovery_ignored_param[] = {
520 	"MaxConnections",
521 	"InitialR2T",
522 	"ImmediateData",
523 	"MaxBurstLength",
524 	"FirstBurstLength"
525 	"MaxOutstandingR2T",
526 	"DataPDUInOrder",
527 	"DataSequenceInOrder",
528 	NULL,
529 };
530 
531 static const char *multi_negot_conn_params[] = {
532 	"MaxRecvDataSegmentLength",
533 	NULL,
534 };
535 
536 /* The following params should be declared by target */
537 static const char *target_declarative_params[] = {
538 	"TargetAlias",
539 	"TargetAddress",
540 	"TargetPortalGroupTag",
541 	NULL,
542 };
543 
544 /* This function is used to construct the data from the special param (e.g.,
545  * MaxRecvDataSegmentLength)
546  * return:
547  * normal: the total len of the data
548  * error: -1
549  */
550 static int
551 iscsi_special_param_construction(struct spdk_iscsi_conn *conn,
552 				 struct iscsi_param *param,
553 				 bool FirstBurstLength_flag, char *data,
554 				 int alloc_len, int total)
555 {
556 	int len;
557 	struct iscsi_param *param_first;
558 	struct iscsi_param *param_max;
559 	uint32_t FirstBurstLength;
560 	uint32_t MaxBurstLength;
561 	char *val;
562 
563 	val = malloc(ISCSI_TEXT_MAX_VAL_LEN + 1);
564 	if (!val) {
565 		SPDK_ERRLOG("malloc() failed for temporary buffer\n");
566 		return -ENOMEM;
567 	}
568 
569 	if (strcasecmp(param->key, "MaxRecvDataSegmentLength") == 0) {
570 		/*
571 		 * MaxRecvDataSegmentLength is sent by both
572 		 *      initiator and target, but is declarative - meaning
573 		 *      each direction can have different values.
574 		 * So when MaxRecvDataSegmentLength is found in the
575 		 *      the parameter set sent from the initiator, add SPDK
576 		 *      iscsi target's MaxRecvDataSegmentLength value to
577 		 *      the returned parameter list.
578 		 */
579 		if (alloc_len - total < 1) {
580 			SPDK_ERRLOG("data space small %d\n", alloc_len);
581 			free(val);
582 			return -1;
583 		}
584 
585 		SPDK_DEBUGLOG(iscsi,
586 			      "returning MaxRecvDataSegmentLength=%d\n",
587 			      SPDK_ISCSI_MAX_RECV_DATA_SEGMENT_LENGTH);
588 		len = snprintf((char *)data + total, alloc_len - total,
589 			       "MaxRecvDataSegmentLength=%d",
590 			       SPDK_ISCSI_MAX_RECV_DATA_SEGMENT_LENGTH);
591 		total += len + 1;
592 	}
593 
594 	if (strcasecmp(param->key, "MaxBurstLength") == 0 &&
595 	    !FirstBurstLength_flag) {
596 		if (alloc_len - total < 1) {
597 			SPDK_ERRLOG("data space small %d\n", alloc_len);
598 			free(val);
599 			return -1;
600 		}
601 
602 		param_first = iscsi_param_find(conn->sess->params,
603 					       "FirstBurstLength");
604 		if (param_first != NULL) {
605 			FirstBurstLength = (uint32_t)strtol(param_first->val, NULL, 10);
606 		} else {
607 			FirstBurstLength = SPDK_ISCSI_FIRST_BURST_LENGTH;
608 		}
609 		param_max = iscsi_param_find(conn->sess->params,
610 					     "MaxBurstLength");
611 		if (param_max != NULL) {
612 			MaxBurstLength = (uint32_t)strtol(param_max->val, NULL, 10);
613 		} else {
614 			MaxBurstLength = SPDK_ISCSI_MAX_BURST_LENGTH;
615 		}
616 
617 		if (FirstBurstLength > MaxBurstLength) {
618 			FirstBurstLength = MaxBurstLength;
619 			if (param_first != NULL) {
620 				free(param_first->val);
621 				snprintf(val, ISCSI_TEXT_MAX_VAL_LEN, "%d",
622 					 FirstBurstLength);
623 				param_first->val = xstrdup(val);
624 			}
625 		}
626 		len = snprintf((char *)data + total, alloc_len - total,
627 			       "FirstBurstLength=%d", FirstBurstLength);
628 		total += len + 1;
629 	}
630 
631 	free(val);
632 	return total;
633 
634 }
635 
636 /**
637  * iscsi_construct_data_from_param:
638  * To construct the data which will be returned to the initiator
639  * return: length of the negotiated data, -1 indicates error;
640  */
641 static int
642 iscsi_construct_data_from_param(struct iscsi_param *param, char *new_val,
643 				char *data, int alloc_len, int total)
644 {
645 	int len;
646 
647 	if (param->type != ISPT_DECLARATIVE &&
648 	    param->type != ISPT_NUMERICAL_DECLARATIVE) {
649 		if (alloc_len - total < 1) {
650 			SPDK_ERRLOG("data space small %d\n", alloc_len);
651 			return -1;
652 		}
653 
654 		SPDK_DEBUGLOG(iscsi, "negotiated %s=%s\n",
655 			      param->key, new_val);
656 		len = snprintf((char *)data + total, alloc_len - total, "%s=%s",
657 			       param->key, new_val);
658 		total += len + 1;
659 	}
660 	return total;
661 }
662 
663 /**
664  * To negotiate param with
665  * type = ISPT_LIST
666  * return: the negotiated value of the key
667  */
668 static char *
669 iscsi_negotiate_param_list(int *add_param_value,
670 			   struct iscsi_param *param,
671 			   char *valid_list, char *in_val,
672 			   char *cur_val)
673 {
674 	char *val_start, *val_end;
675 	char *in_start, *in_end;
676 	int flag = 0;
677 
678 	if (add_param_value == NULL) {
679 		return NULL;
680 	}
681 
682 	in_start = in_val;
683 	do {
684 		if ((in_end = strchr(in_start, (int)',')) != NULL) {
685 			*in_end = '\0';
686 		}
687 		val_start = valid_list;
688 		do {
689 			if ((val_end = strchr(val_start, (int)',')) != NULL) {
690 				*val_end = '\0';
691 			}
692 			if (strcasecmp(in_start, val_start) == 0) {
693 				SPDK_DEBUGLOG(iscsi, "match %s\n",
694 					      val_start);
695 				flag = 1;
696 				break;
697 			}
698 			if (val_end) {
699 				*val_end = ',';
700 				val_start = val_end + 1;
701 			}
702 		} while (val_end);
703 		if (flag) {
704 			break;
705 		}
706 		if (in_end) {
707 			*in_end = ',';
708 			in_start = in_end + 1;
709 		}
710 	} while (in_end);
711 
712 	return flag ? val_start : NULL;
713 }
714 
715 /**
716  * To negotiate param with
717  * type = ISPT_NUMERICAL_MIN/MAX, ISPT_NUMERICAL_DECLARATIVE
718  * return: the negotiated value of the key
719  */
720 static char *
721 iscsi_negotiate_param_numerical(int *add_param_value,
722 				struct iscsi_param *param,
723 				char *valid_list, char *in_val,
724 				char *cur_val)
725 {
726 	char *valid_next;
727 	char *new_val = NULL;
728 	char *min_val, *max_val;
729 	int val_i, cur_val_i;
730 	int min_i, max_i;
731 
732 	if (add_param_value == NULL) {
733 		return NULL;
734 	}
735 
736 	val_i = (int)strtol(param->val, NULL, 10);
737 	/* check whether the key is FirstBurstLength, if that we use in_val */
738 	if (strcasecmp(param->key, "FirstBurstLength") == 0) {
739 		val_i = (int)strtol(in_val, NULL, 10);
740 	}
741 
742 	cur_val_i = (int)strtol(cur_val, NULL, 10);
743 	valid_next = valid_list;
744 	min_val = spdk_strsepq(&valid_next, ",");
745 	max_val = spdk_strsepq(&valid_next, ",");
746 	min_i = (min_val != NULL) ? (int)strtol(min_val, NULL, 10) : 0;
747 	max_i = (max_val != NULL) ? (int)strtol(max_val, NULL, 10) : 0;
748 	if (val_i < min_i || val_i > max_i) {
749 		SPDK_DEBUGLOG(iscsi, "key %.64s reject\n", param->key);
750 		new_val = NULL;
751 	} else {
752 		switch (param->type) {
753 		case ISPT_NUMERICAL_MIN:
754 			if (val_i > cur_val_i) {
755 				val_i = cur_val_i;
756 			}
757 			break;
758 		case ISPT_NUMERICAL_MAX:
759 			if (val_i < cur_val_i) {
760 				val_i = cur_val_i;
761 			}
762 			break;
763 		default:
764 			break;
765 		}
766 		snprintf(in_val, ISCSI_TEXT_MAX_VAL_LEN, "%d", val_i);
767 		new_val = in_val;
768 	}
769 
770 	return new_val;
771 }
772 
773 /**
774  * To negotiate param with
775  * type = ISPT_BOOLEAN_OR, ISPT_BOOLEAN_AND
776  * return: the negotiated value of the key
777  */
778 static char *
779 iscsi_negotiate_param_boolean(int *add_param_value,
780 			      struct iscsi_param *param,
781 			      char *in_val, char *cur_val,
782 			      const char *value)
783 {
784 	char *new_val = NULL;
785 
786 	if (add_param_value == NULL) {
787 		return NULL;
788 	}
789 
790 	/* Make sure the val is Yes or No */
791 	if (!((strcasecmp(in_val, "Yes") == 0) ||
792 	      (strcasecmp(in_val, "No") == 0))) {
793 		/* unknown value */
794 		snprintf(in_val, ISCSI_TEXT_MAX_VAL_LEN + 1, "%s", "Reject");
795 		new_val = in_val;
796 		*add_param_value = 1;
797 		return new_val;
798 	}
799 
800 	if (strcasecmp(cur_val, value) == 0) {
801 		snprintf(in_val, ISCSI_TEXT_MAX_VAL_LEN + 1, "%s", value);
802 		new_val = in_val;
803 	} else {
804 		new_val = param->val;
805 	}
806 
807 	return new_val;
808 }
809 
810 /**
811  * The entry function to handle each type of the param
812  * return value: the new negotiated value
813  */
814 static char *
815 iscsi_negotiate_param_all(int *add_param_value, struct iscsi_param *param,
816 			  char *valid_list, char *in_val, char *cur_val)
817 {
818 	char *new_val;
819 	switch (param->type) {
820 	case ISPT_LIST:
821 		new_val = iscsi_negotiate_param_list(add_param_value,
822 						     param,
823 						     valid_list,
824 						     in_val,
825 						     cur_val);
826 		break;
827 
828 	case ISPT_NUMERICAL_MIN:
829 	case ISPT_NUMERICAL_MAX:
830 	case ISPT_NUMERICAL_DECLARATIVE:
831 		new_val = iscsi_negotiate_param_numerical(add_param_value,
832 				param,
833 				valid_list,
834 				in_val,
835 				cur_val);
836 		break;
837 
838 	case ISPT_BOOLEAN_OR:
839 		new_val = iscsi_negotiate_param_boolean(add_param_value,
840 							param,
841 							in_val,
842 							cur_val,
843 							"Yes");
844 		break;
845 	case ISPT_BOOLEAN_AND:
846 		new_val = iscsi_negotiate_param_boolean(add_param_value,
847 							param,
848 							in_val,
849 							cur_val,
850 							"No");
851 		break;
852 
853 	default:
854 		snprintf(in_val, ISCSI_TEXT_MAX_VAL_LEN + 1, "%s", param->val);
855 		new_val = in_val;
856 		break;
857 	}
858 
859 	return new_val;
860 }
861 
862 /**
863  * This function is used to judge whether the param is in session's params or
864  * connection's params
865  */
866 static int
867 iscsi_negotiate_param_init(struct spdk_iscsi_conn *conn,
868 			   struct iscsi_param **cur_param_p,
869 			   struct iscsi_param **params_dst_p,
870 			   struct iscsi_param *param)
871 {
872 	int index;
873 
874 	*cur_param_p = iscsi_param_find(*params_dst_p, param->key);
875 	if (*cur_param_p == NULL) {
876 		*params_dst_p = conn->sess->params;
877 		*cur_param_p = iscsi_param_find(*params_dst_p, param->key);
878 		if (*cur_param_p == NULL) {
879 			if ((strncasecmp(param->key, "X-", 2) == 0) ||
880 			    (strncasecmp(param->key, "X#", 2) == 0)) {
881 				/* Extension Key */
882 				SPDK_DEBUGLOG(iscsi,
883 					      "extension key %.64s\n",
884 					      param->key);
885 			} else {
886 				SPDK_ERRLOG("unknown key %.64s\n", param->key);
887 			}
888 			return 1;
889 		} else {
890 			index = (*cur_param_p)->state_index;
891 			if (conn->sess_param_state_negotiated[index] &&
892 			    !iscsi_find_key_in_array(param->key,
893 						     target_declarative_params)) {
894 				return SPDK_ISCSI_PARAMETER_EXCHANGE_NOT_ONCE;
895 			}
896 			conn->sess_param_state_negotiated[index] = true;
897 		}
898 	} else {
899 		index = (*cur_param_p)->state_index;
900 		if (conn->conn_param_state_negotiated[index] &&
901 		    !iscsi_find_key_in_array(param->key,
902 					     multi_negot_conn_params)) {
903 			return SPDK_ISCSI_PARAMETER_EXCHANGE_NOT_ONCE;
904 		}
905 		conn->conn_param_state_negotiated[index] = true;
906 	}
907 
908 	return 0;
909 }
910 
911 int
912 iscsi_negotiate_params(struct spdk_iscsi_conn *conn,
913 		       struct iscsi_param **params, uint8_t *data, int alloc_len,
914 		       int data_len)
915 {
916 	struct iscsi_param *param;
917 	struct iscsi_param *cur_param;
918 	char *valid_list, *in_val;
919 	char *cur_val;
920 	char *new_val;
921 	int discovery;
922 	int total;
923 	int rc;
924 	uint32_t FirstBurstLength;
925 	uint32_t MaxBurstLength;
926 	bool FirstBurstLength_flag = false;
927 	int type;
928 
929 	total = data_len;
930 	if (data_len < 0) {
931 		assert(false);
932 		return -EINVAL;
933 	}
934 	if (alloc_len < 1) {
935 		return 0;
936 	}
937 	if (total > alloc_len) {
938 		total = alloc_len;
939 		data[total - 1] = '\0';
940 		return total;
941 	}
942 
943 	if (*params == NULL) {
944 		/* no input */
945 		return total;
946 	}
947 
948 	/* discovery? */
949 	discovery = 0;
950 	cur_param = iscsi_param_find(*params, "SessionType");
951 	if (cur_param == NULL) {
952 		cur_param = iscsi_param_find(conn->sess->params, "SessionType");
953 		if (cur_param == NULL) {
954 			/* no session type */
955 		} else {
956 			if (strcasecmp(cur_param->val, "Discovery") == 0) {
957 				discovery = 1;
958 			}
959 		}
960 	} else {
961 		if (strcasecmp(cur_param->val, "Discovery") == 0) {
962 			discovery = 1;
963 		}
964 	}
965 
966 	/* for temporary store */
967 	valid_list = malloc(ISCSI_TEXT_MAX_VAL_LEN + 1);
968 	if (!valid_list) {
969 		SPDK_ERRLOG("malloc() failed for valid_list\n");
970 		return -ENOMEM;
971 	}
972 
973 	in_val = malloc(ISCSI_TEXT_MAX_VAL_LEN + 1);
974 	if (!in_val) {
975 		SPDK_ERRLOG("malloc() failed for in_val\n");
976 		free(valid_list);
977 		return -ENOMEM;
978 	}
979 
980 	cur_val = malloc(ISCSI_TEXT_MAX_VAL_LEN + 1);
981 	if (!cur_val) {
982 		SPDK_ERRLOG("malloc() failed for cur_val\n");
983 		free(valid_list);
984 		free(in_val);
985 		return -ENOMEM;
986 	}
987 
988 	/* To adjust the location of FirstBurstLength location and put it to
989 	 *  the end, then we can always firstly determine the MaxBurstLength
990 	 */
991 	param = iscsi_param_find(*params, "MaxBurstLength");
992 	if (param != NULL) {
993 		param = iscsi_param_find(*params, "FirstBurstLength");
994 
995 		/* check the existence of FirstBurstLength */
996 		if (param != NULL) {
997 			FirstBurstLength_flag = true;
998 			if (param->next != NULL) {
999 				snprintf(in_val, ISCSI_TEXT_MAX_VAL_LEN + 1, "%s", param->val);
1000 				type = param->type;
1001 				iscsi_param_add(params, "FirstBurstLength",
1002 						in_val, NULL, type);
1003 			}
1004 		}
1005 	}
1006 
1007 	for (param = *params; param != NULL; param = param->next) {
1008 		struct iscsi_param *params_dst = conn->params;
1009 		int add_param_value = 0;
1010 		new_val = NULL;
1011 		param->type = ISPT_INVALID;
1012 
1013 		/* sendtargets is special */
1014 		if (strcasecmp(param->key, "SendTargets") == 0) {
1015 			continue;
1016 		}
1017 		/* CHAP keys */
1018 		if (iscsi_find_key_in_array(param->key, chap_type)) {
1019 			continue;
1020 		}
1021 
1022 		/* 12.2, 12.10, 12.11, 12.13, 12.14, 12.17, 12.18, 12.19 */
1023 		if (discovery &&
1024 		    iscsi_find_key_in_array(param->key, discovery_ignored_param)) {
1025 			snprintf(in_val, ISCSI_TEXT_MAX_VAL_LEN + 1, "%s", "Irrelevant");
1026 			new_val = in_val;
1027 			add_param_value = 1;
1028 		} else {
1029 			rc = iscsi_negotiate_param_init(conn,
1030 							&cur_param,
1031 							&params_dst,
1032 							param);
1033 			if (rc < 0) {
1034 				free(valid_list);
1035 				free(in_val);
1036 				free(cur_val);
1037 				return rc;
1038 			} else if (rc > 0) {
1039 				snprintf(in_val, ISCSI_TEXT_MAX_VAL_LEN + 1, "%s", "NotUnderstood");
1040 				new_val = in_val;
1041 				add_param_value = 1;
1042 			} else {
1043 				snprintf(valid_list, ISCSI_TEXT_MAX_VAL_LEN + 1, "%s", cur_param->list);
1044 				snprintf(cur_val, ISCSI_TEXT_MAX_VAL_LEN + 1, "%s", cur_param->val);
1045 				param->type = cur_param->type;
1046 			}
1047 		}
1048 
1049 		if (param->type > 0) {
1050 			snprintf(in_val, ISCSI_TEXT_MAX_VAL_LEN + 1, "%s", param->val);
1051 
1052 			/* "NotUnderstood" value shouldn't be assigned to "Understood" key */
1053 			if (strcasecmp(in_val, "NotUnderstood") == 0) {
1054 				free(in_val);
1055 				free(valid_list);
1056 				free(cur_val);
1057 				return SPDK_ISCSI_LOGIN_ERROR_PARAMETER;
1058 			}
1059 
1060 			if (strcasecmp(param->key, "FirstBurstLength") == 0) {
1061 				FirstBurstLength = (uint32_t)strtol(param->val, NULL,
1062 								    10);
1063 				new_val = iscsi_param_get_val(conn->sess->params,
1064 							      "MaxBurstLength");
1065 				if (new_val != NULL) {
1066 					MaxBurstLength = (uint32_t) strtol(new_val, NULL,
1067 									   10);
1068 				} else {
1069 					MaxBurstLength = SPDK_ISCSI_MAX_BURST_LENGTH;
1070 				}
1071 				if (FirstBurstLength < SPDK_ISCSI_MAX_FIRST_BURST_LENGTH &&
1072 				    FirstBurstLength > MaxBurstLength) {
1073 					FirstBurstLength = MaxBurstLength;
1074 					snprintf(in_val, ISCSI_TEXT_MAX_VAL_LEN, "%d",
1075 						 FirstBurstLength);
1076 				}
1077 			}
1078 
1079 			/* prevent target's declarative params from being changed by initiator */
1080 			if (iscsi_find_key_in_array(param->key, target_declarative_params)) {
1081 				add_param_value = 1;
1082 			}
1083 
1084 			new_val = iscsi_negotiate_param_all(&add_param_value,
1085 							    param,
1086 							    valid_list,
1087 							    in_val,
1088 							    cur_val);
1089 		}
1090 
1091 		/* check the negotiated value of the key */
1092 		if (new_val != NULL) {
1093 			/* add_param_value = 0 means updating the value of
1094 			 *      existed key in the connection's parameters
1095 			 */
1096 			if (add_param_value == 0) {
1097 				iscsi_param_set(params_dst, param->key, new_val);
1098 			}
1099 			total = iscsi_construct_data_from_param(param,
1100 								new_val,
1101 								data,
1102 								alloc_len,
1103 								total);
1104 			if (total < 0) {
1105 				goto final_return;
1106 			}
1107 
1108 			total = iscsi_special_param_construction(conn,
1109 					param,
1110 					FirstBurstLength_flag,
1111 					data,
1112 					alloc_len,
1113 					total);
1114 			if (total < 0) {
1115 				goto final_return;
1116 			}
1117 		} else {
1118 			total = -1;
1119 			break;
1120 		}
1121 	}
1122 
1123 final_return:
1124 	free(valid_list);
1125 	free(in_val);
1126 	free(cur_val);
1127 
1128 	return total;
1129 }
1130 
1131 int
1132 iscsi_copy_param2var(struct spdk_iscsi_conn *conn)
1133 {
1134 	const char *val;
1135 
1136 	val = iscsi_param_get_val(conn->params, "MaxRecvDataSegmentLength");
1137 	if (val == NULL) {
1138 		SPDK_ERRLOG("Getval MaxRecvDataSegmentLength failed\n");
1139 		return -1;
1140 	}
1141 	SPDK_DEBUGLOG(iscsi,
1142 		      "copy MaxRecvDataSegmentLength=%s\n", val);
1143 	conn->MaxRecvDataSegmentLength = (int)strtol(val, NULL, 10);
1144 	if (conn->MaxRecvDataSegmentLength > SPDK_BDEV_LARGE_BUF_MAX_SIZE) {
1145 		conn->MaxRecvDataSegmentLength = SPDK_BDEV_LARGE_BUF_MAX_SIZE;
1146 	}
1147 
1148 	val = iscsi_param_get_val(conn->params, "HeaderDigest");
1149 	if (val == NULL) {
1150 		SPDK_ERRLOG("Getval HeaderDigest failed\n");
1151 		return -1;
1152 	}
1153 	if (strcasecmp(val, "CRC32C") == 0) {
1154 		SPDK_DEBUGLOG(iscsi, "set HeaderDigest=1\n");
1155 		conn->header_digest = 1;
1156 	} else {
1157 		SPDK_DEBUGLOG(iscsi, "set HeaderDigest=0\n");
1158 		conn->header_digest = 0;
1159 	}
1160 	val = iscsi_param_get_val(conn->params, "DataDigest");
1161 	if (val == NULL) {
1162 		SPDK_ERRLOG("Getval DataDigest failed\n");
1163 		return -1;
1164 	}
1165 	if (strcasecmp(val, "CRC32C") == 0) {
1166 		SPDK_DEBUGLOG(iscsi, "set DataDigest=1\n");
1167 		conn->data_digest = 1;
1168 	} else {
1169 		SPDK_DEBUGLOG(iscsi, "set DataDigest=0\n");
1170 		conn->data_digest = 0;
1171 	}
1172 
1173 	val = iscsi_param_get_val(conn->sess->params, "MaxConnections");
1174 	if (val == NULL) {
1175 		SPDK_ERRLOG("Getval MaxConnections failed\n");
1176 		return -1;
1177 	}
1178 	SPDK_DEBUGLOG(iscsi, "copy MaxConnections=%s\n", val);
1179 	conn->sess->MaxConnections = (uint32_t) strtol(val, NULL, 10);
1180 	val = iscsi_param_get_val(conn->sess->params, "MaxOutstandingR2T");
1181 	if (val == NULL) {
1182 		SPDK_ERRLOG("Getval MaxOutstandingR2T failed\n");
1183 		return -1;
1184 	}
1185 	SPDK_DEBUGLOG(iscsi, "copy MaxOutstandingR2T=%s\n", val);
1186 	conn->sess->MaxOutstandingR2T = (uint32_t) strtol(val, NULL, 10);
1187 	val = iscsi_param_get_val(conn->sess->params, "FirstBurstLength");
1188 	if (val == NULL) {
1189 		SPDK_ERRLOG("Getval FirstBurstLength failed\n");
1190 		return -1;
1191 	}
1192 	SPDK_DEBUGLOG(iscsi, "copy FirstBurstLength=%s\n", val);
1193 	conn->sess->FirstBurstLength = (uint32_t) strtol(val, NULL, 10);
1194 	val = iscsi_param_get_val(conn->sess->params, "MaxBurstLength");
1195 	if (val == NULL) {
1196 		SPDK_ERRLOG("Getval MaxBurstLength failed\n");
1197 		return -1;
1198 	}
1199 	SPDK_DEBUGLOG(iscsi, "copy MaxBurstLength=%s\n", val);
1200 	conn->sess->MaxBurstLength = (uint32_t) strtol(val, NULL, 10);
1201 	val = iscsi_param_get_val(conn->sess->params, "InitialR2T");
1202 	if (val == NULL) {
1203 		SPDK_ERRLOG("Getval InitialR2T failed\n");
1204 		return -1;
1205 	}
1206 	if (strcasecmp(val, "Yes") == 0) {
1207 		SPDK_DEBUGLOG(iscsi, "set InitialR2T=1\n");
1208 		conn->sess->InitialR2T = true;
1209 	} else {
1210 		SPDK_DEBUGLOG(iscsi, "set InitialR2T=0\n");
1211 		conn->sess->InitialR2T = false;
1212 	}
1213 	val = iscsi_param_get_val(conn->sess->params, "ImmediateData");
1214 	if (val == NULL) {
1215 		SPDK_ERRLOG("Getval ImmediateData failed\n");
1216 		return -1;
1217 	}
1218 	if (strcasecmp(val, "Yes") == 0) {
1219 		SPDK_DEBUGLOG(iscsi, "set ImmediateData=1\n");
1220 		conn->sess->ImmediateData = true;
1221 	} else {
1222 		SPDK_DEBUGLOG(iscsi, "set ImmediateData=0\n");
1223 		conn->sess->ImmediateData = false;
1224 	}
1225 	return 0;
1226 }
1227