xref: /spdk/lib/iscsi/param.c (revision 7506a7aa53d239f533af3bc768f0d2af55e735fe)
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  * Data must point to a valid pointer if len > 0.
311  */
312 int
313 iscsi_parse_params(struct iscsi_param **params, const uint8_t *data,
314 		   int len, bool cbit_enabled, char **partial_parameter)
315 {
316 	int rc, offset = 0;
317 	char *p;
318 	int i;
319 
320 	/* Spec does not disallow TEXT PDUs with zero length, just return
321 	 * immediately in that case, since there is no param data to parse
322 	 * and any existing partial parameter would remain as-is.
323 	 */
324 	if (len == 0) {
325 		return 0;
326 	}
327 
328 	assert(data != NULL);
329 
330 	/* strip the partial text parameters if previous PDU have C enabled */
331 	if (partial_parameter && *partial_parameter) {
332 		for (i = 0; i < len && data[i] != '\0'; i++) {
333 			;
334 		}
335 		p = spdk_sprintf_alloc("%s%s", *partial_parameter, (const char *)data);
336 		if (!p) {
337 			return -1;
338 		}
339 		rc = iscsi_parse_param(params, p, i + strlen(*partial_parameter));
340 		free(p);
341 		if (rc < 0) {
342 			return -1;
343 		}
344 		free(*partial_parameter);
345 		*partial_parameter = NULL;
346 
347 		data = data + i + 1;
348 		len = len - (i + 1);
349 	}
350 
351 	/* strip the partial text parameters if C bit is enabled */
352 	if (cbit_enabled) {
353 		if (partial_parameter == NULL) {
354 			SPDK_ERRLOG("C bit set but no partial parameters provided\n");
355 			return -1;
356 		}
357 
358 		/*
359 		 * reverse iterate the string from the tail not including '\0'
360 		 */
361 		for (i = len - 1; data[i] != '\0' && i > 0; i--) {
362 			;
363 		}
364 		if (i != 0) {
365 			/* We found a NULL character - don't copy it into the
366 			 * partial parameter.
367 			 */
368 			i++;
369 		}
370 
371 		*partial_parameter = calloc(1, len - i + 1);
372 		if (*partial_parameter == NULL) {
373 			SPDK_ERRLOG("could not allocate partial parameter\n");
374 			return -1;
375 		}
376 		memcpy(*partial_parameter, &data[i], len - i);
377 		if (i == 0) {
378 			/* No full parameters to parse - so return now. */
379 			return 0;
380 		} else {
381 			len = i - 1;
382 		}
383 	}
384 
385 	while (offset < len && data[offset] != '\0') {
386 		rc = iscsi_parse_param(params, data + offset, len - offset);
387 		if (rc < 0) {
388 			return -1;
389 		}
390 		offset += rc;
391 	}
392 	return 0;
393 }
394 
395 char *
396 iscsi_param_get_val(struct iscsi_param *params, const char *key)
397 {
398 	struct iscsi_param *param;
399 
400 	param = iscsi_param_find(params, key);
401 	if (param == NULL) {
402 		return NULL;
403 	}
404 	return param->val;
405 }
406 
407 int
408 iscsi_param_eq_val(struct iscsi_param *params, const char *key,
409 		   const char *val)
410 {
411 	struct iscsi_param *param;
412 
413 	param = iscsi_param_find(params, key);
414 	if (param == NULL) {
415 		return 0;
416 	}
417 	if (strcasecmp(param->val, val) == 0) {
418 		return 1;
419 	}
420 	return 0;
421 }
422 
423 struct iscsi_param_table {
424 	const char *key;
425 	const char *val;
426 	const char *list;
427 	int type;
428 };
429 
430 static const struct iscsi_param_table conn_param_table[] = {
431 	{ "HeaderDigest", "None", "CRC32C,None", ISPT_LIST },
432 	{ "DataDigest", "None", "CRC32C,None", ISPT_LIST },
433 	{ "MaxRecvDataSegmentLength", "8192", "512,16777215", ISPT_NUMERICAL_DECLARATIVE },
434 	{ "OFMarker", "No", "Yes,No", ISPT_BOOLEAN_AND },
435 	{ "IFMarker", "No", "Yes,No", ISPT_BOOLEAN_AND },
436 	{ "OFMarkInt", "1", "1,65535", ISPT_NUMERICAL_MIN },
437 	{ "IFMarkInt", "1", "1,65535", ISPT_NUMERICAL_MIN },
438 	{ "AuthMethod", "None", "CHAP,None", ISPT_LIST },
439 	{ "CHAP_A", "5", "5", ISPT_LIST },
440 	{ "CHAP_N", "", "", ISPT_DECLARATIVE },
441 	{ "CHAP_R", "", "", ISPT_DECLARATIVE },
442 	{ "CHAP_I", "", "", ISPT_DECLARATIVE },
443 	{ "CHAP_C", "", "", ISPT_DECLARATIVE },
444 	{ NULL, NULL, NULL, ISPT_INVALID },
445 };
446 
447 static const struct iscsi_param_table sess_param_table[] = {
448 	{ "MaxConnections", "1", "1,65535", ISPT_NUMERICAL_MIN },
449 #if 0
450 	/* need special handling */
451 	{ "SendTargets", "", "", ISPT_DECLARATIVE },
452 #endif
453 	{ "TargetName", "", "", ISPT_DECLARATIVE },
454 	{ "InitiatorName", "", "", ISPT_DECLARATIVE },
455 	{ "TargetAlias", "", "", ISPT_DECLARATIVE },
456 	{ "InitiatorAlias", "", "", ISPT_DECLARATIVE },
457 	{ "TargetAddress", "", "", ISPT_DECLARATIVE },
458 	{ "TargetPortalGroupTag", "1", "1,65535", ISPT_NUMERICAL_DECLARATIVE },
459 	{ "InitialR2T", "Yes", "Yes,No", ISPT_BOOLEAN_OR },
460 	{ "ImmediateData", "Yes", "Yes,No", ISPT_BOOLEAN_AND },
461 	{ "MaxBurstLength", "262144", "512,16777215", ISPT_NUMERICAL_MIN },
462 	{ "FirstBurstLength", "65536", "512,16777215", ISPT_NUMERICAL_MIN },
463 	{ "DefaultTime2Wait", "2", "0,3600", ISPT_NUMERICAL_MAX },
464 	{ "DefaultTime2Retain", "20", "0,3600", ISPT_NUMERICAL_MIN },
465 	{ "MaxOutstandingR2T", "1", "1,65536", ISPT_NUMERICAL_MIN },
466 	{ "DataPDUInOrder", "Yes", "Yes,No", ISPT_BOOLEAN_OR },
467 	{ "DataSequenceInOrder", "Yes", "Yes,No", ISPT_BOOLEAN_OR },
468 	{ "ErrorRecoveryLevel", "0", "0,2", ISPT_NUMERICAL_MIN },
469 	{ "SessionType", "Normal", "Normal,Discovery", ISPT_DECLARATIVE },
470 	{ NULL, NULL, NULL, ISPT_INVALID },
471 };
472 
473 static int
474 iscsi_params_init_internal(struct iscsi_param **params,
475 			   const struct iscsi_param_table *table)
476 {
477 	int rc;
478 	int i;
479 	struct iscsi_param *param;
480 
481 	for (i = 0; table[i].key != NULL; i++) {
482 		rc = iscsi_param_add(params, table[i].key, table[i].val,
483 				     table[i].list, table[i].type);
484 		if (rc < 0) {
485 			SPDK_ERRLOG("iscsi_param_add() failed\n");
486 			return -1;
487 		}
488 		param = iscsi_param_find(*params, table[i].key);
489 		if (param != NULL) {
490 			param->state_index = i;
491 		} else {
492 			SPDK_ERRLOG("iscsi_param_find() failed\n");
493 			return -1;
494 		}
495 	}
496 
497 	return 0;
498 }
499 
500 int
501 iscsi_conn_params_init(struct iscsi_param **params)
502 {
503 	return iscsi_params_init_internal(params, &conn_param_table[0]);
504 }
505 
506 int
507 iscsi_sess_params_init(struct iscsi_param **params)
508 {
509 	return iscsi_params_init_internal(params, &sess_param_table[0]);
510 }
511 
512 static const char *chap_type[] = {
513 	"CHAP_A",
514 	"CHAP_N",
515 	"CHAP_R",
516 	"CHAP_I",
517 	"CHAP_C",
518 	NULL,
519 };
520 
521 static const char *discovery_ignored_param[] = {
522 	"MaxConnections",
523 	"InitialR2T",
524 	"ImmediateData",
525 	"MaxBurstLength",
526 	"FirstBurstLength"
527 	"MaxOutstandingR2T",
528 	"DataPDUInOrder",
529 	"DataSequenceInOrder",
530 	NULL,
531 };
532 
533 static const char *multi_negot_conn_params[] = {
534 	"MaxRecvDataSegmentLength",
535 	NULL,
536 };
537 
538 /* The following params should be declared by target */
539 static const char *target_declarative_params[] = {
540 	"TargetAlias",
541 	"TargetAddress",
542 	"TargetPortalGroupTag",
543 	NULL,
544 };
545 
546 /* This function is used to construct the data from the special param (e.g.,
547  * MaxRecvDataSegmentLength)
548  * return:
549  * normal: the total len of the data
550  * error: -1
551  */
552 static int
553 iscsi_special_param_construction(struct spdk_iscsi_conn *conn,
554 				 struct iscsi_param *param,
555 				 bool FirstBurstLength_flag, char *data,
556 				 int alloc_len, int total)
557 {
558 	int len;
559 	struct iscsi_param *param_first;
560 	struct iscsi_param *param_max;
561 	uint32_t FirstBurstLength;
562 	uint32_t MaxBurstLength;
563 	char *val;
564 
565 	val = malloc(ISCSI_TEXT_MAX_VAL_LEN + 1);
566 	if (!val) {
567 		SPDK_ERRLOG("malloc() failed for temporary buffer\n");
568 		return -ENOMEM;
569 	}
570 
571 	if (strcasecmp(param->key, "MaxRecvDataSegmentLength") == 0) {
572 		/*
573 		 * MaxRecvDataSegmentLength is sent by both
574 		 *      initiator and target, but is declarative - meaning
575 		 *      each direction can have different values.
576 		 * So when MaxRecvDataSegmentLength is found in the
577 		 *      the parameter set sent from the initiator, add SPDK
578 		 *      iscsi target's MaxRecvDataSegmentLength value to
579 		 *      the returned parameter list.
580 		 */
581 		if (alloc_len - total < 1) {
582 			SPDK_ERRLOG("data space small %d\n", alloc_len);
583 			free(val);
584 			return -1;
585 		}
586 
587 		SPDK_DEBUGLOG(iscsi,
588 			      "returning MaxRecvDataSegmentLength=%d\n",
589 			      SPDK_ISCSI_MAX_RECV_DATA_SEGMENT_LENGTH);
590 		len = snprintf((char *)data + total, alloc_len - total,
591 			       "MaxRecvDataSegmentLength=%d",
592 			       SPDK_ISCSI_MAX_RECV_DATA_SEGMENT_LENGTH);
593 		total += len + 1;
594 	}
595 
596 	if (strcasecmp(param->key, "MaxBurstLength") == 0 &&
597 	    !FirstBurstLength_flag) {
598 		if (alloc_len - total < 1) {
599 			SPDK_ERRLOG("data space small %d\n", alloc_len);
600 			free(val);
601 			return -1;
602 		}
603 
604 		param_first = iscsi_param_find(conn->sess->params,
605 					       "FirstBurstLength");
606 		if (param_first != NULL) {
607 			FirstBurstLength = (uint32_t)strtol(param_first->val, NULL, 10);
608 		} else {
609 			FirstBurstLength = SPDK_ISCSI_FIRST_BURST_LENGTH;
610 		}
611 		param_max = iscsi_param_find(conn->sess->params,
612 					     "MaxBurstLength");
613 		if (param_max != NULL) {
614 			MaxBurstLength = (uint32_t)strtol(param_max->val, NULL, 10);
615 		} else {
616 			MaxBurstLength = SPDK_ISCSI_MAX_BURST_LENGTH;
617 		}
618 
619 		if (FirstBurstLength > MaxBurstLength) {
620 			FirstBurstLength = MaxBurstLength;
621 			if (param_first != NULL) {
622 				free(param_first->val);
623 				snprintf(val, ISCSI_TEXT_MAX_VAL_LEN, "%d",
624 					 FirstBurstLength);
625 				param_first->val = xstrdup(val);
626 			}
627 		}
628 		len = snprintf((char *)data + total, alloc_len - total,
629 			       "FirstBurstLength=%d", FirstBurstLength);
630 		total += len + 1;
631 	}
632 
633 	free(val);
634 	return total;
635 
636 }
637 
638 /**
639  * iscsi_construct_data_from_param:
640  * To construct the data which will be returned to the initiator
641  * return: length of the negotiated data, -1 indicates error;
642  */
643 static int
644 iscsi_construct_data_from_param(struct iscsi_param *param, char *new_val,
645 				char *data, int alloc_len, int total)
646 {
647 	int len;
648 
649 	if (param->type != ISPT_DECLARATIVE &&
650 	    param->type != ISPT_NUMERICAL_DECLARATIVE) {
651 		if (alloc_len - total < 1) {
652 			SPDK_ERRLOG("data space small %d\n", alloc_len);
653 			return -1;
654 		}
655 
656 		SPDK_DEBUGLOG(iscsi, "negotiated %s=%s\n",
657 			      param->key, new_val);
658 		len = snprintf((char *)data + total, alloc_len - total, "%s=%s",
659 			       param->key, new_val);
660 		total += len + 1;
661 	}
662 	return total;
663 }
664 
665 /**
666  * To negotiate param with
667  * type = ISPT_LIST
668  * return: the negotiated value of the key
669  */
670 static char *
671 iscsi_negotiate_param_list(int *add_param_value,
672 			   struct iscsi_param *param,
673 			   char *valid_list, char *in_val,
674 			   char *cur_val)
675 {
676 	char *val_start, *val_end;
677 	char *in_start, *in_end;
678 	int flag = 0;
679 
680 	if (add_param_value == NULL) {
681 		return NULL;
682 	}
683 
684 	in_start = in_val;
685 	do {
686 		if ((in_end = strchr(in_start, (int)',')) != NULL) {
687 			*in_end = '\0';
688 		}
689 		val_start = valid_list;
690 		do {
691 			if ((val_end = strchr(val_start, (int)',')) != NULL) {
692 				*val_end = '\0';
693 			}
694 			if (strcasecmp(in_start, val_start) == 0) {
695 				SPDK_DEBUGLOG(iscsi, "match %s\n",
696 					      val_start);
697 				flag = 1;
698 				break;
699 			}
700 			if (val_end) {
701 				*val_end = ',';
702 				val_start = val_end + 1;
703 			}
704 		} while (val_end);
705 		if (flag) {
706 			break;
707 		}
708 		if (in_end) {
709 			*in_end = ',';
710 			in_start = in_end + 1;
711 		}
712 	} while (in_end);
713 
714 	return flag ? val_start : NULL;
715 }
716 
717 /**
718  * To negotiate param with
719  * type = ISPT_NUMERICAL_MIN/MAX, ISPT_NUMERICAL_DECLARATIVE
720  * return: the negotiated value of the key
721  */
722 static char *
723 iscsi_negotiate_param_numerical(int *add_param_value,
724 				struct iscsi_param *param,
725 				char *valid_list, char *in_val,
726 				char *cur_val)
727 {
728 	char *valid_next;
729 	char *new_val = NULL;
730 	char *min_val, *max_val;
731 	int val_i, cur_val_i;
732 	int min_i, max_i;
733 
734 	if (add_param_value == NULL) {
735 		return NULL;
736 	}
737 
738 	val_i = (int)strtol(param->val, NULL, 10);
739 	/* check whether the key is FirstBurstLength, if that we use in_val */
740 	if (strcasecmp(param->key, "FirstBurstLength") == 0) {
741 		val_i = (int)strtol(in_val, NULL, 10);
742 	}
743 
744 	cur_val_i = (int)strtol(cur_val, NULL, 10);
745 	valid_next = valid_list;
746 	min_val = spdk_strsepq(&valid_next, ",");
747 	max_val = spdk_strsepq(&valid_next, ",");
748 	min_i = (min_val != NULL) ? (int)strtol(min_val, NULL, 10) : 0;
749 	max_i = (max_val != NULL) ? (int)strtol(max_val, NULL, 10) : 0;
750 	if (val_i < min_i || val_i > max_i) {
751 		SPDK_DEBUGLOG(iscsi, "key %.64s reject\n", param->key);
752 		new_val = NULL;
753 	} else {
754 		switch (param->type) {
755 		case ISPT_NUMERICAL_MIN:
756 			if (val_i > cur_val_i) {
757 				val_i = cur_val_i;
758 			}
759 			break;
760 		case ISPT_NUMERICAL_MAX:
761 			if (val_i < cur_val_i) {
762 				val_i = cur_val_i;
763 			}
764 			break;
765 		default:
766 			break;
767 		}
768 		snprintf(in_val, ISCSI_TEXT_MAX_VAL_LEN, "%d", val_i);
769 		new_val = in_val;
770 	}
771 
772 	return new_val;
773 }
774 
775 /**
776  * To negotiate param with
777  * type = ISPT_BOOLEAN_OR, ISPT_BOOLEAN_AND
778  * return: the negotiated value of the key
779  */
780 static char *
781 iscsi_negotiate_param_boolean(int *add_param_value,
782 			      struct iscsi_param *param,
783 			      char *in_val, char *cur_val,
784 			      const char *value)
785 {
786 	char *new_val = NULL;
787 
788 	if (add_param_value == NULL) {
789 		return NULL;
790 	}
791 
792 	/* Make sure the val is Yes or No */
793 	if (!((strcasecmp(in_val, "Yes") == 0) ||
794 	      (strcasecmp(in_val, "No") == 0))) {
795 		/* unknown value */
796 		snprintf(in_val, ISCSI_TEXT_MAX_VAL_LEN + 1, "%s", "Reject");
797 		new_val = in_val;
798 		*add_param_value = 1;
799 		return new_val;
800 	}
801 
802 	if (strcasecmp(cur_val, value) == 0) {
803 		snprintf(in_val, ISCSI_TEXT_MAX_VAL_LEN + 1, "%s", value);
804 		new_val = in_val;
805 	} else {
806 		new_val = param->val;
807 	}
808 
809 	return new_val;
810 }
811 
812 /**
813  * The entry function to handle each type of the param
814  * return value: the new negotiated value
815  */
816 static char *
817 iscsi_negotiate_param_all(int *add_param_value, struct iscsi_param *param,
818 			  char *valid_list, char *in_val, char *cur_val)
819 {
820 	char *new_val;
821 	switch (param->type) {
822 	case ISPT_LIST:
823 		new_val = iscsi_negotiate_param_list(add_param_value,
824 						     param,
825 						     valid_list,
826 						     in_val,
827 						     cur_val);
828 		break;
829 
830 	case ISPT_NUMERICAL_MIN:
831 	case ISPT_NUMERICAL_MAX:
832 	case ISPT_NUMERICAL_DECLARATIVE:
833 		new_val = iscsi_negotiate_param_numerical(add_param_value,
834 				param,
835 				valid_list,
836 				in_val,
837 				cur_val);
838 		break;
839 
840 	case ISPT_BOOLEAN_OR:
841 		new_val = iscsi_negotiate_param_boolean(add_param_value,
842 							param,
843 							in_val,
844 							cur_val,
845 							"Yes");
846 		break;
847 	case ISPT_BOOLEAN_AND:
848 		new_val = iscsi_negotiate_param_boolean(add_param_value,
849 							param,
850 							in_val,
851 							cur_val,
852 							"No");
853 		break;
854 
855 	default:
856 		snprintf(in_val, ISCSI_TEXT_MAX_VAL_LEN + 1, "%s", param->val);
857 		new_val = in_val;
858 		break;
859 	}
860 
861 	return new_val;
862 }
863 
864 /**
865  * This function is used to judge whether the param is in session's params or
866  * connection's params
867  */
868 static int
869 iscsi_negotiate_param_init(struct spdk_iscsi_conn *conn,
870 			   struct iscsi_param **cur_param_p,
871 			   struct iscsi_param **params_dst_p,
872 			   struct iscsi_param *param)
873 {
874 	int index;
875 
876 	*cur_param_p = iscsi_param_find(*params_dst_p, param->key);
877 	if (*cur_param_p == NULL) {
878 		*params_dst_p = conn->sess->params;
879 		*cur_param_p = iscsi_param_find(*params_dst_p, param->key);
880 		if (*cur_param_p == NULL) {
881 			if ((strncasecmp(param->key, "X-", 2) == 0) ||
882 			    (strncasecmp(param->key, "X#", 2) == 0)) {
883 				/* Extension Key */
884 				SPDK_DEBUGLOG(iscsi,
885 					      "extension key %.64s\n",
886 					      param->key);
887 			} else {
888 				SPDK_ERRLOG("unknown key %.64s\n", param->key);
889 			}
890 			return 1;
891 		} else {
892 			index = (*cur_param_p)->state_index;
893 			if (conn->sess_param_state_negotiated[index] &&
894 			    !iscsi_find_key_in_array(param->key,
895 						     target_declarative_params)) {
896 				return SPDK_ISCSI_PARAMETER_EXCHANGE_NOT_ONCE;
897 			}
898 			conn->sess_param_state_negotiated[index] = true;
899 		}
900 	} else {
901 		index = (*cur_param_p)->state_index;
902 		if (conn->conn_param_state_negotiated[index] &&
903 		    !iscsi_find_key_in_array(param->key,
904 					     multi_negot_conn_params)) {
905 			return SPDK_ISCSI_PARAMETER_EXCHANGE_NOT_ONCE;
906 		}
907 		conn->conn_param_state_negotiated[index] = true;
908 	}
909 
910 	return 0;
911 }
912 
913 int
914 iscsi_negotiate_params(struct spdk_iscsi_conn *conn,
915 		       struct iscsi_param **params, uint8_t *data, int alloc_len,
916 		       int data_len)
917 {
918 	struct iscsi_param *param;
919 	struct iscsi_param *cur_param;
920 	char *valid_list, *in_val;
921 	char *cur_val;
922 	char *new_val;
923 	int discovery;
924 	int total;
925 	int rc;
926 	uint32_t FirstBurstLength;
927 	uint32_t MaxBurstLength;
928 	bool FirstBurstLength_flag = false;
929 	int type;
930 
931 	total = data_len;
932 	if (data_len < 0) {
933 		assert(false);
934 		return -EINVAL;
935 	}
936 	if (alloc_len < 1) {
937 		return 0;
938 	}
939 	if (total > alloc_len) {
940 		total = alloc_len;
941 		data[total - 1] = '\0';
942 		return total;
943 	}
944 
945 	if (*params == NULL) {
946 		/* no input */
947 		return total;
948 	}
949 
950 	/* discovery? */
951 	discovery = 0;
952 	cur_param = iscsi_param_find(*params, "SessionType");
953 	if (cur_param == NULL) {
954 		cur_param = iscsi_param_find(conn->sess->params, "SessionType");
955 		if (cur_param == NULL) {
956 			/* no session type */
957 		} else {
958 			if (strcasecmp(cur_param->val, "Discovery") == 0) {
959 				discovery = 1;
960 			}
961 		}
962 	} else {
963 		if (strcasecmp(cur_param->val, "Discovery") == 0) {
964 			discovery = 1;
965 		}
966 	}
967 
968 	/* for temporary store */
969 	valid_list = malloc(ISCSI_TEXT_MAX_VAL_LEN + 1);
970 	if (!valid_list) {
971 		SPDK_ERRLOG("malloc() failed for valid_list\n");
972 		return -ENOMEM;
973 	}
974 
975 	in_val = malloc(ISCSI_TEXT_MAX_VAL_LEN + 1);
976 	if (!in_val) {
977 		SPDK_ERRLOG("malloc() failed for in_val\n");
978 		free(valid_list);
979 		return -ENOMEM;
980 	}
981 
982 	cur_val = malloc(ISCSI_TEXT_MAX_VAL_LEN + 1);
983 	if (!cur_val) {
984 		SPDK_ERRLOG("malloc() failed for cur_val\n");
985 		free(valid_list);
986 		free(in_val);
987 		return -ENOMEM;
988 	}
989 
990 	/* To adjust the location of FirstBurstLength location and put it to
991 	 *  the end, then we can always firstly determine the MaxBurstLength
992 	 */
993 	param = iscsi_param_find(*params, "MaxBurstLength");
994 	if (param != NULL) {
995 		param = iscsi_param_find(*params, "FirstBurstLength");
996 
997 		/* check the existence of FirstBurstLength */
998 		if (param != NULL) {
999 			FirstBurstLength_flag = true;
1000 			if (param->next != NULL) {
1001 				snprintf(in_val, ISCSI_TEXT_MAX_VAL_LEN + 1, "%s", param->val);
1002 				type = param->type;
1003 				iscsi_param_add(params, "FirstBurstLength",
1004 						in_val, NULL, type);
1005 			}
1006 		}
1007 	}
1008 
1009 	for (param = *params; param != NULL; param = param->next) {
1010 		struct iscsi_param *params_dst = conn->params;
1011 		int add_param_value = 0;
1012 		new_val = NULL;
1013 		param->type = ISPT_INVALID;
1014 
1015 		/* sendtargets is special */
1016 		if (strcasecmp(param->key, "SendTargets") == 0) {
1017 			continue;
1018 		}
1019 		/* CHAP keys */
1020 		if (iscsi_find_key_in_array(param->key, chap_type)) {
1021 			continue;
1022 		}
1023 
1024 		/* 12.2, 12.10, 12.11, 12.13, 12.14, 12.17, 12.18, 12.19 */
1025 		if (discovery &&
1026 		    iscsi_find_key_in_array(param->key, discovery_ignored_param)) {
1027 			snprintf(in_val, ISCSI_TEXT_MAX_VAL_LEN + 1, "%s", "Irrelevant");
1028 			new_val = in_val;
1029 			add_param_value = 1;
1030 		} else {
1031 			rc = iscsi_negotiate_param_init(conn,
1032 							&cur_param,
1033 							&params_dst,
1034 							param);
1035 			if (rc < 0) {
1036 				free(valid_list);
1037 				free(in_val);
1038 				free(cur_val);
1039 				return rc;
1040 			} else if (rc > 0) {
1041 				snprintf(in_val, ISCSI_TEXT_MAX_VAL_LEN + 1, "%s", "NotUnderstood");
1042 				new_val = in_val;
1043 				add_param_value = 1;
1044 			} else {
1045 				snprintf(valid_list, ISCSI_TEXT_MAX_VAL_LEN + 1, "%s", cur_param->list);
1046 				snprintf(cur_val, ISCSI_TEXT_MAX_VAL_LEN + 1, "%s", cur_param->val);
1047 				param->type = cur_param->type;
1048 			}
1049 		}
1050 
1051 		if (param->type > 0) {
1052 			snprintf(in_val, ISCSI_TEXT_MAX_VAL_LEN + 1, "%s", param->val);
1053 
1054 			/* "NotUnderstood" value shouldn't be assigned to "Understood" key */
1055 			if (strcasecmp(in_val, "NotUnderstood") == 0) {
1056 				free(in_val);
1057 				free(valid_list);
1058 				free(cur_val);
1059 				return SPDK_ISCSI_LOGIN_ERROR_PARAMETER;
1060 			}
1061 
1062 			if (strcasecmp(param->key, "FirstBurstLength") == 0) {
1063 				FirstBurstLength = (uint32_t)strtol(param->val, NULL,
1064 								    10);
1065 				new_val = iscsi_param_get_val(conn->sess->params,
1066 							      "MaxBurstLength");
1067 				if (new_val != NULL) {
1068 					MaxBurstLength = (uint32_t) strtol(new_val, NULL,
1069 									   10);
1070 				} else {
1071 					MaxBurstLength = SPDK_ISCSI_MAX_BURST_LENGTH;
1072 				}
1073 				if (FirstBurstLength < SPDK_ISCSI_MAX_FIRST_BURST_LENGTH &&
1074 				    FirstBurstLength > MaxBurstLength) {
1075 					FirstBurstLength = MaxBurstLength;
1076 					snprintf(in_val, ISCSI_TEXT_MAX_VAL_LEN, "%d",
1077 						 FirstBurstLength);
1078 				}
1079 			}
1080 
1081 			/* prevent target's declarative params from being changed by initiator */
1082 			if (iscsi_find_key_in_array(param->key, target_declarative_params)) {
1083 				add_param_value = 1;
1084 			}
1085 
1086 			new_val = iscsi_negotiate_param_all(&add_param_value,
1087 							    param,
1088 							    valid_list,
1089 							    in_val,
1090 							    cur_val);
1091 		}
1092 
1093 		/* check the negotiated value of the key */
1094 		if (new_val != NULL) {
1095 			/* add_param_value = 0 means updating the value of
1096 			 *      existed key in the connection's parameters
1097 			 */
1098 			if (add_param_value == 0) {
1099 				iscsi_param_set(params_dst, param->key, new_val);
1100 			}
1101 			total = iscsi_construct_data_from_param(param,
1102 								new_val,
1103 								data,
1104 								alloc_len,
1105 								total);
1106 			if (total < 0) {
1107 				goto final_return;
1108 			}
1109 
1110 			total = iscsi_special_param_construction(conn,
1111 					param,
1112 					FirstBurstLength_flag,
1113 					data,
1114 					alloc_len,
1115 					total);
1116 			if (total < 0) {
1117 				goto final_return;
1118 			}
1119 		} else {
1120 			total = -1;
1121 			break;
1122 		}
1123 	}
1124 
1125 final_return:
1126 	free(valid_list);
1127 	free(in_val);
1128 	free(cur_val);
1129 
1130 	return total;
1131 }
1132 
1133 int
1134 iscsi_copy_param2var(struct spdk_iscsi_conn *conn)
1135 {
1136 	const char *val;
1137 
1138 	val = iscsi_param_get_val(conn->params, "MaxRecvDataSegmentLength");
1139 	if (val == NULL) {
1140 		SPDK_ERRLOG("Getval MaxRecvDataSegmentLength failed\n");
1141 		return -1;
1142 	}
1143 	SPDK_DEBUGLOG(iscsi,
1144 		      "copy MaxRecvDataSegmentLength=%s\n", val);
1145 	conn->MaxRecvDataSegmentLength = (int)strtol(val, NULL, 10);
1146 	if (conn->MaxRecvDataSegmentLength > SPDK_BDEV_LARGE_BUF_MAX_SIZE) {
1147 		conn->MaxRecvDataSegmentLength = SPDK_BDEV_LARGE_BUF_MAX_SIZE;
1148 	}
1149 
1150 	val = iscsi_param_get_val(conn->params, "HeaderDigest");
1151 	if (val == NULL) {
1152 		SPDK_ERRLOG("Getval HeaderDigest failed\n");
1153 		return -1;
1154 	}
1155 	if (strcasecmp(val, "CRC32C") == 0) {
1156 		SPDK_DEBUGLOG(iscsi, "set HeaderDigest=1\n");
1157 		conn->header_digest = 1;
1158 	} else {
1159 		SPDK_DEBUGLOG(iscsi, "set HeaderDigest=0\n");
1160 		conn->header_digest = 0;
1161 	}
1162 	val = iscsi_param_get_val(conn->params, "DataDigest");
1163 	if (val == NULL) {
1164 		SPDK_ERRLOG("Getval DataDigest failed\n");
1165 		return -1;
1166 	}
1167 	if (strcasecmp(val, "CRC32C") == 0) {
1168 		SPDK_DEBUGLOG(iscsi, "set DataDigest=1\n");
1169 		conn->data_digest = 1;
1170 	} else {
1171 		SPDK_DEBUGLOG(iscsi, "set DataDigest=0\n");
1172 		conn->data_digest = 0;
1173 	}
1174 
1175 	val = iscsi_param_get_val(conn->sess->params, "MaxConnections");
1176 	if (val == NULL) {
1177 		SPDK_ERRLOG("Getval MaxConnections failed\n");
1178 		return -1;
1179 	}
1180 	SPDK_DEBUGLOG(iscsi, "copy MaxConnections=%s\n", val);
1181 	conn->sess->MaxConnections = (uint32_t) strtol(val, NULL, 10);
1182 	val = iscsi_param_get_val(conn->sess->params, "MaxOutstandingR2T");
1183 	if (val == NULL) {
1184 		SPDK_ERRLOG("Getval MaxOutstandingR2T failed\n");
1185 		return -1;
1186 	}
1187 	SPDK_DEBUGLOG(iscsi, "copy MaxOutstandingR2T=%s\n", val);
1188 	conn->sess->MaxOutstandingR2T = (uint32_t) strtol(val, NULL, 10);
1189 	val = iscsi_param_get_val(conn->sess->params, "FirstBurstLength");
1190 	if (val == NULL) {
1191 		SPDK_ERRLOG("Getval FirstBurstLength failed\n");
1192 		return -1;
1193 	}
1194 	SPDK_DEBUGLOG(iscsi, "copy FirstBurstLength=%s\n", val);
1195 	conn->sess->FirstBurstLength = (uint32_t) strtol(val, NULL, 10);
1196 	val = iscsi_param_get_val(conn->sess->params, "MaxBurstLength");
1197 	if (val == NULL) {
1198 		SPDK_ERRLOG("Getval MaxBurstLength failed\n");
1199 		return -1;
1200 	}
1201 	SPDK_DEBUGLOG(iscsi, "copy MaxBurstLength=%s\n", val);
1202 	conn->sess->MaxBurstLength = (uint32_t) strtol(val, NULL, 10);
1203 	val = iscsi_param_get_val(conn->sess->params, "InitialR2T");
1204 	if (val == NULL) {
1205 		SPDK_ERRLOG("Getval InitialR2T failed\n");
1206 		return -1;
1207 	}
1208 	if (strcasecmp(val, "Yes") == 0) {
1209 		SPDK_DEBUGLOG(iscsi, "set InitialR2T=1\n");
1210 		conn->sess->InitialR2T = true;
1211 	} else {
1212 		SPDK_DEBUGLOG(iscsi, "set InitialR2T=0\n");
1213 		conn->sess->InitialR2T = false;
1214 	}
1215 	val = iscsi_param_get_val(conn->sess->params, "ImmediateData");
1216 	if (val == NULL) {
1217 		SPDK_ERRLOG("Getval ImmediateData failed\n");
1218 		return -1;
1219 	}
1220 	if (strcasecmp(val, "Yes") == 0) {
1221 		SPDK_DEBUGLOG(iscsi, "set ImmediateData=1\n");
1222 		conn->sess->ImmediateData = true;
1223 	} else {
1224 		SPDK_DEBUGLOG(iscsi, "set ImmediateData=0\n");
1225 		conn->sess->ImmediateData = false;
1226 	}
1227 	return 0;
1228 }
1229