1 /*-
2 * Copyright (c) 2001-2008, by Cisco Systems, Inc. All rights reserved.
3 * Copyright (c) 2008-2012, by Randall Stewart. All rights reserved.
4 * Copyright (c) 2008-2012, by Michael Tuexen. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are met:
8 *
9 * a) Redistributions of source code must retain the above copyright notice,
10 * this list of conditions and the following disclaimer.
11 *
12 * b) Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in
14 * the documentation and/or other materials provided with the distribution.
15 *
16 * c) Neither the name of Cisco Systems, Inc. nor the names of its
17 * contributors may be used to endorse or promote products derived
18 * from this software without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
22 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
24 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
30 * THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD: releng/11.2/sys/netinet/sctp_auth.c 334743 2018-06-06 22:34:20Z tuexen $");
35
36 #include <netinet/sctp_os.h>
37 #include <netinet/sctp.h>
38 #include <netinet/sctp_header.h>
39 #include <netinet/sctp_pcb.h>
40 #include <netinet/sctp_var.h>
41 #include <netinet/sctp_sysctl.h>
42 #include <netinet/sctputil.h>
43 #include <netinet/sctp_indata.h>
44 #include <netinet/sctp_output.h>
45 #include <netinet/sctp_auth.h>
46
47 #ifdef SCTP_DEBUG
48 #define SCTP_AUTH_DEBUG (SCTP_BASE_SYSCTL(sctp_debug_on) & SCTP_DEBUG_AUTH1)
49 #define SCTP_AUTH_DEBUG2 (SCTP_BASE_SYSCTL(sctp_debug_on) & SCTP_DEBUG_AUTH2)
50 #endif /* SCTP_DEBUG */
51
52
53 void
54 sctp_clear_chunklist(sctp_auth_chklist_t *chklist)
55 {
56 memset(chklist, 0, sizeof(*chklist));
57 /* chklist->num_chunks = 0; */
58 }
59
60 sctp_auth_chklist_t *
61 sctp_alloc_chunklist(void)
62 {
63 sctp_auth_chklist_t *chklist;
64
65 SCTP_MALLOC(chklist, sctp_auth_chklist_t *, sizeof(*chklist),
66 SCTP_M_AUTH_CL);
67 if (chklist == NULL) {
68 SCTPDBG(SCTP_DEBUG_AUTH1, "sctp_alloc_chunklist: failed to get memory!\n");
69 } else {
70 sctp_clear_chunklist(chklist);
71 }
72 return (chklist);
73 }
74
75 void
76 sctp_free_chunklist(sctp_auth_chklist_t *list)
77 {
78 if (list != NULL)
79 SCTP_FREE(list, SCTP_M_AUTH_CL);
80 }
81
82 sctp_auth_chklist_t *
83 sctp_copy_chunklist(sctp_auth_chklist_t *list)
84 {
85 sctp_auth_chklist_t *new_list;
86
87 if (list == NULL)
88 return (NULL);
89
90 /* get a new list */
91 new_list = sctp_alloc_chunklist();
92 if (new_list == NULL)
93 return (NULL);
94 /* copy it */
95 memcpy(new_list, list, sizeof(*new_list));
96
97 return (new_list);
98 }
99
100
101 /*
102 * add a chunk to the required chunks list
103 */
104 int
105 sctp_auth_add_chunk(uint8_t chunk, sctp_auth_chklist_t *list)
106 {
107 if (list == NULL)
108 return (-1);
109
110 /* is chunk restricted? */
111 if ((chunk == SCTP_INITIATION) ||
112 (chunk == SCTP_INITIATION_ACK) ||
113 (chunk == SCTP_SHUTDOWN_COMPLETE) ||
114 (chunk == SCTP_AUTHENTICATION)) {
115 return (-1);
116 }
117 if (list->chunks[chunk] == 0) {
118 list->chunks[chunk] = 1;
119 list->num_chunks++;
120 SCTPDBG(SCTP_DEBUG_AUTH1,
121 "SCTP: added chunk %u (0x%02x) to Auth list\n",
122 chunk, chunk);
123 }
124 return (0);
125 }
126
127 /*
128 * delete a chunk from the required chunks list
129 */
130 int
131 sctp_auth_delete_chunk(uint8_t chunk, sctp_auth_chklist_t *list)
132 {
133 if (list == NULL)
134 return (-1);
135
136 if (list->chunks[chunk] == 1) {
137 list->chunks[chunk] = 0;
138 list->num_chunks--;
139 SCTPDBG(SCTP_DEBUG_AUTH1,
140 "SCTP: deleted chunk %u (0x%02x) from Auth list\n",
141 chunk, chunk);
142 }
143 return (0);
144 }
145
146 size_t
147 sctp_auth_get_chklist_size(const sctp_auth_chklist_t *list)
148 {
149 if (list == NULL)
150 return (0);
151 else
152 return (list->num_chunks);
153 }
154
155 /*
156 * return the current number and list of required chunks caller must
157 * guarantee ptr has space for up to 256 bytes
158 */
159 int
160 sctp_serialize_auth_chunks(const sctp_auth_chklist_t *list, uint8_t *ptr)
161 {
162 int i, count = 0;
163
164 if (list == NULL)
165 return (0);
166
167 for (i = 0; i < 256; i++) {
168 if (list->chunks[i] != 0) {
169 *ptr++ = i;
170 count++;
171 }
172 }
173 return (count);
174 }
175
176 int
177 sctp_pack_auth_chunks(const sctp_auth_chklist_t *list, uint8_t *ptr)
178 {
179 int i, size = 0;
180
181 if (list == NULL)
182 return (0);
183
184 if (list->num_chunks <= 32) {
185 /* just list them, one byte each */
186 for (i = 0; i < 256; i++) {
187 if (list->chunks[i] != 0) {
188 *ptr++ = i;
189 size++;
190 }
191 }
192 } else {
193 int index, offset;
194
195 /* pack into a 32 byte bitfield */
196 for (i = 0; i < 256; i++) {
197 if (list->chunks[i] != 0) {
198 index = i / 8;
199 offset = i % 8;
200 ptr[index] |= (1 << offset);
201 }
202 }
203 size = 32;
204 }
205 return (size);
206 }
207
208 int
209 sctp_unpack_auth_chunks(const uint8_t *ptr, uint8_t num_chunks,
210 sctp_auth_chklist_t *list)
211 {
212 int i;
213 int size;
214
215 if (list == NULL)
216 return (0);
217
218 if (num_chunks <= 32) {
219 /* just pull them, one byte each */
220 for (i = 0; i < num_chunks; i++) {
221 (void)sctp_auth_add_chunk(*ptr++, list);
222 }
223 size = num_chunks;
224 } else {
225 int index, offset;
226
227 /* unpack from a 32 byte bitfield */
228 for (index = 0; index < 32; index++) {
229 for (offset = 0; offset < 8; offset++) {
230 if (ptr[index] & (1 << offset)) {
231 (void)sctp_auth_add_chunk((index * 8) + offset, list);
232 }
233 }
234 }
235 size = 32;
236 }
237 return (size);
238 }
239
240
241 /*
242 * allocate structure space for a key of length keylen
243 */
244 sctp_key_t *
245 sctp_alloc_key(uint32_t keylen)
246 {
247 sctp_key_t *new_key;
248
249 SCTP_MALLOC(new_key, sctp_key_t *, sizeof(*new_key) + keylen,
250 SCTP_M_AUTH_KY);
251 if (new_key == NULL) {
252 /* out of memory */
253 return (NULL);
254 }
255 new_key->keylen = keylen;
256 return (new_key);
257 }
258
259 void
260 sctp_free_key(sctp_key_t *key)
261 {
262 if (key != NULL)
263 SCTP_FREE(key, SCTP_M_AUTH_KY);
264 }
265
266 void
267 sctp_print_key(sctp_key_t *key, const char *str)
268 {
269 uint32_t i;
270
271 if (key == NULL) {
272 SCTP_PRINTF("%s: [Null key]\n", str);
273 return;
274 }
275 SCTP_PRINTF("%s: len %u, ", str, key->keylen);
276 if (key->keylen) {
277 for (i = 0; i < key->keylen; i++)
278 SCTP_PRINTF("%02x", key->key[i]);
279 SCTP_PRINTF("\n");
280 } else {
281 SCTP_PRINTF("[Null key]\n");
282 }
283 }
284
285 void
286 sctp_show_key(sctp_key_t *key, const char *str)
287 {
288 uint32_t i;
289
290 if (key == NULL) {
291 SCTP_PRINTF("%s: [Null key]\n", str);
292 return;
293 }
294 SCTP_PRINTF("%s: len %u, ", str, key->keylen);
295 if (key->keylen) {
296 for (i = 0; i < key->keylen; i++)
297 SCTP_PRINTF("%02x", key->key[i]);
298 SCTP_PRINTF("\n");
299 } else {
300 SCTP_PRINTF("[Null key]\n");
301 }
302 }
303
304 static uint32_t
305 sctp_get_keylen(sctp_key_t *key)
306 {
307 if (key != NULL)
308 return (key->keylen);
309 else
310 return (0);
311 }
312
313 /*
314 * generate a new random key of length 'keylen'
315 */
316 sctp_key_t *
317 sctp_generate_random_key(uint32_t keylen)
318 {
319 sctp_key_t *new_key;
320
321 new_key = sctp_alloc_key(keylen);
322 if (new_key == NULL) {
323 /* out of memory */
324 return (NULL);
325 }
326 SCTP_READ_RANDOM(new_key->key, keylen);
327 new_key->keylen = keylen;
328 return (new_key);
329 }
330
331 sctp_key_t *
332 sctp_set_key(uint8_t *key, uint32_t keylen)
333 {
334 sctp_key_t *new_key;
335
336 new_key = sctp_alloc_key(keylen);
337 if (new_key == NULL) {
338 /* out of memory */
339 return (NULL);
340 }
341 memcpy(new_key->key, key, keylen);
342 return (new_key);
343 }
344
345 /*-
346 * given two keys of variable size, compute which key is "larger/smaller"
347 * returns: 1 if key1 > key2
348 * -1 if key1 < key2
349 * 0 if key1 = key2
350 */
351 static int
352 sctp_compare_key(sctp_key_t *key1, sctp_key_t *key2)
353 {
354 uint32_t maxlen;
355 uint32_t i;
356 uint32_t key1len, key2len;
357 uint8_t *key_1, *key_2;
358 uint8_t val1, val2;
359
360 /* sanity/length check */
361 key1len = sctp_get_keylen(key1);
362 key2len = sctp_get_keylen(key2);
363 if ((key1len == 0) && (key2len == 0))
364 return (0);
365 else if (key1len == 0)
366 return (-1);
367 else if (key2len == 0)
368 return (1);
369
370 if (key1len < key2len) {
371 maxlen = key2len;
372 } else {
373 maxlen = key1len;
374 }
375 key_1 = key1->key;
376 key_2 = key2->key;
377 /* check for numeric equality */
378 for (i = 0; i < maxlen; i++) {
379 /* left-pad with zeros */
380 val1 = (i < (maxlen - key1len)) ? 0 : *(key_1++);
381 val2 = (i < (maxlen - key2len)) ? 0 : *(key_2++);
382 if (val1 > val2) {
383 return (1);
384 } else if (val1 < val2) {
385 return (-1);
386 }
387 }
388 /* keys are equal value, so check lengths */
389 if (key1len == key2len)
390 return (0);
391 else if (key1len < key2len)
392 return (-1);
393 else
394 return (1);
395 }
396
397 /*
398 * generate the concatenated keying material based on the two keys and the
399 * shared key (if available). draft-ietf-tsvwg-auth specifies the specific
400 * order for concatenation
401 */
402 sctp_key_t *
403 sctp_compute_hashkey(sctp_key_t *key1, sctp_key_t *key2, sctp_key_t *shared)
404 {
405 uint32_t keylen;
406 sctp_key_t *new_key;
407 uint8_t *key_ptr;
408
409 keylen = sctp_get_keylen(key1) + sctp_get_keylen(key2) +
410 sctp_get_keylen(shared);
411
412 if (keylen > 0) {
413 /* get space for the new key */
414 new_key = sctp_alloc_key(keylen);
415 if (new_key == NULL) {
416 /* out of memory */
417 return (NULL);
418 }
419 new_key->keylen = keylen;
420 key_ptr = new_key->key;
421 } else {
422 /* all keys empty/null?! */
423 return (NULL);
424 }
425
426 /* concatenate the keys */
427 if (sctp_compare_key(key1, key2) <= 0) {
428 /* key is shared + key1 + key2 */
429 if (sctp_get_keylen(shared)) {
430 memcpy(key_ptr, shared->key, shared->keylen);
431 key_ptr += shared->keylen;
432 }
433 if (sctp_get_keylen(key1)) {
434 memcpy(key_ptr, key1->key, key1->keylen);
435 key_ptr += key1->keylen;
436 }
437 if (sctp_get_keylen(key2)) {
438 memcpy(key_ptr, key2->key, key2->keylen);
439 }
440 } else {
441 /* key is shared + key2 + key1 */
442 if (sctp_get_keylen(shared)) {
443 memcpy(key_ptr, shared->key, shared->keylen);
444 key_ptr += shared->keylen;
445 }
446 if (sctp_get_keylen(key2)) {
447 memcpy(key_ptr, key2->key, key2->keylen);
448 key_ptr += key2->keylen;
449 }
450 if (sctp_get_keylen(key1)) {
451 memcpy(key_ptr, key1->key, key1->keylen);
452 }
453 }
454 return (new_key);
455 }
456
457
458 sctp_sharedkey_t *
459 sctp_alloc_sharedkey(void)
460 {
461 sctp_sharedkey_t *new_key;
462
463 SCTP_MALLOC(new_key, sctp_sharedkey_t *, sizeof(*new_key),
464 SCTP_M_AUTH_KY);
465 if (new_key == NULL) {
466 /* out of memory */
467 return (NULL);
468 }
469 new_key->keyid = 0;
470 new_key->key = NULL;
471 new_key->refcount = 1;
472 new_key->deactivated = 0;
473 return (new_key);
474 }
475
476 void
477 sctp_free_sharedkey(sctp_sharedkey_t *skey)
478 {
479 if (skey == NULL)
480 return;
481
482 if (SCTP_DECREMENT_AND_CHECK_REFCOUNT(&skey->refcount)) {
483 if (skey->key != NULL)
484 sctp_free_key(skey->key);
485 SCTP_FREE(skey, SCTP_M_AUTH_KY);
486 }
487 }
488
489 sctp_sharedkey_t *
490 sctp_find_sharedkey(struct sctp_keyhead *shared_keys, uint16_t key_id)
491 {
492 sctp_sharedkey_t *skey;
493
494 LIST_FOREACH(skey, shared_keys, next) {
495 if (skey->keyid == key_id)
496 return (skey);
497 }
498 return (NULL);
499 }
500
501 int
502 sctp_insert_sharedkey(struct sctp_keyhead *shared_keys,
503 sctp_sharedkey_t *new_skey)
504 {
505 sctp_sharedkey_t *skey;
506
507 if ((shared_keys == NULL) || (new_skey == NULL))
508 return (EINVAL);
509
510 /* insert into an empty list? */
511 if (LIST_EMPTY(shared_keys)) {
512 LIST_INSERT_HEAD(shared_keys, new_skey, next);
513 return (0);
514 }
515 /* insert into the existing list, ordered by key id */
516 LIST_FOREACH(skey, shared_keys, next) {
517 if (new_skey->keyid < skey->keyid) {
518 /* insert it before here */
519 LIST_INSERT_BEFORE(skey, new_skey, next);
520 return (0);
521 } else if (new_skey->keyid == skey->keyid) {
522 /* replace the existing key */
523 /* verify this key *can* be replaced */
524 if ((skey->deactivated) && (skey->refcount > 1)) {
525 SCTPDBG(SCTP_DEBUG_AUTH1,
526 "can't replace shared key id %u\n",
527 new_skey->keyid);
528 return (EBUSY);
529 }
530 SCTPDBG(SCTP_DEBUG_AUTH1,
531 "replacing shared key id %u\n",
532 new_skey->keyid);
533 LIST_INSERT_BEFORE(skey, new_skey, next);
534 LIST_REMOVE(skey, next);
535 sctp_free_sharedkey(skey);
536 return (0);
537 }
538 if (LIST_NEXT(skey, next) == NULL) {
539 /* belongs at the end of the list */
540 LIST_INSERT_AFTER(skey, new_skey, next);
541 return (0);
542 }
543 }
544 /* shouldn't reach here */
545 return (EINVAL);
546 }
547
548 void
549 sctp_auth_key_acquire(struct sctp_tcb *stcb, uint16_t key_id)
550 {
551 sctp_sharedkey_t *skey;
552
553 /* find the shared key */
554 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, key_id);
555
556 /* bump the ref count */
557 if (skey) {
558 atomic_add_int(&skey->refcount, 1);
559 SCTPDBG(SCTP_DEBUG_AUTH2,
560 "%s: stcb %p key %u refcount acquire to %d\n",
561 __func__, (void *)stcb, key_id, skey->refcount);
562 }
563 }
564
565 void
566 sctp_auth_key_release(struct sctp_tcb *stcb, uint16_t key_id, int so_locked
567 #if !defined(__APPLE__) && !defined(SCTP_SO_LOCK_TESTING)
568 SCTP_UNUSED
569 #endif
570 )
571 {
572 sctp_sharedkey_t *skey;
573
574 /* find the shared key */
575 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, key_id);
576
577 /* decrement the ref count */
578 if (skey) {
579 SCTPDBG(SCTP_DEBUG_AUTH2,
580 "%s: stcb %p key %u refcount release to %d\n",
581 __func__, (void *)stcb, key_id, skey->refcount);
582
583 /* see if a notification should be generated */
584 if ((skey->refcount <= 2) && (skey->deactivated)) {
585 /* notify ULP that key is no longer used */
586 sctp_ulp_notify(SCTP_NOTIFY_AUTH_FREE_KEY, stcb,
587 key_id, 0, so_locked);
588 SCTPDBG(SCTP_DEBUG_AUTH2,
589 "%s: stcb %p key %u no longer used, %d\n",
590 __func__, (void *)stcb, key_id, skey->refcount);
591 }
592 sctp_free_sharedkey(skey);
593 }
594 }
595
596 static sctp_sharedkey_t *
597 sctp_copy_sharedkey(const sctp_sharedkey_t *skey)
598 {
599 sctp_sharedkey_t *new_skey;
600
601 if (skey == NULL)
602 return (NULL);
603 new_skey = sctp_alloc_sharedkey();
604 if (new_skey == NULL)
605 return (NULL);
606 if (skey->key != NULL)
607 new_skey->key = sctp_set_key(skey->key->key, skey->key->keylen);
608 else
609 new_skey->key = NULL;
610 new_skey->keyid = skey->keyid;
611 return (new_skey);
612 }
613
614 int
615 sctp_copy_skeylist(const struct sctp_keyhead *src, struct sctp_keyhead *dest)
616 {
617 sctp_sharedkey_t *skey, *new_skey;
618 int count = 0;
619
620 if ((src == NULL) || (dest == NULL))
621 return (0);
622 LIST_FOREACH(skey, src, next) {
623 new_skey = sctp_copy_sharedkey(skey);
624 if (new_skey != NULL) {
625 if (sctp_insert_sharedkey(dest, new_skey)) {
626 sctp_free_sharedkey(new_skey);
627 } else {
628 count++;
629 }
630 }
631 }
632 return (count);
633 }
634
635
636 sctp_hmaclist_t *
637 sctp_alloc_hmaclist(uint16_t num_hmacs)
638 {
639 sctp_hmaclist_t *new_list;
640 int alloc_size;
641
642 alloc_size = sizeof(*new_list) + num_hmacs * sizeof(new_list->hmac[0]);
643 SCTP_MALLOC(new_list, sctp_hmaclist_t *, alloc_size,
644 SCTP_M_AUTH_HL);
645 if (new_list == NULL) {
646 /* out of memory */
647 return (NULL);
648 }
649 new_list->max_algo = num_hmacs;
650 new_list->num_algo = 0;
651 return (new_list);
652 }
653
654 void
655 sctp_free_hmaclist(sctp_hmaclist_t *list)
656 {
657 if (list != NULL) {
658 SCTP_FREE(list, SCTP_M_AUTH_HL);
659 list = NULL;
660 }
661 }
662
663 int
664 sctp_auth_add_hmacid(sctp_hmaclist_t *list, uint16_t hmac_id)
665 {
666 int i;
667
668 if (list == NULL)
669 return (-1);
670 if (list->num_algo == list->max_algo) {
671 SCTPDBG(SCTP_DEBUG_AUTH1,
672 "SCTP: HMAC id list full, ignoring add %u\n", hmac_id);
673 return (-1);
674 }
675 if ((hmac_id != SCTP_AUTH_HMAC_ID_SHA1) &&
676 (hmac_id != SCTP_AUTH_HMAC_ID_SHA256)) {
677 return (-1);
678 }
679 /* Now is it already in the list */
680 for (i = 0; i < list->num_algo; i++) {
681 if (list->hmac[i] == hmac_id) {
682 /* already in list */
683 return (-1);
684 }
685 }
686 SCTPDBG(SCTP_DEBUG_AUTH1, "SCTP: add HMAC id %u to list\n", hmac_id);
687 list->hmac[list->num_algo++] = hmac_id;
688 return (0);
689 }
690
691 sctp_hmaclist_t *
692 sctp_copy_hmaclist(sctp_hmaclist_t *list)
693 {
694 sctp_hmaclist_t *new_list;
695 int i;
696
697 if (list == NULL)
698 return (NULL);
699 /* get a new list */
700 new_list = sctp_alloc_hmaclist(list->max_algo);
701 if (new_list == NULL)
702 return (NULL);
703 /* copy it */
704 new_list->max_algo = list->max_algo;
705 new_list->num_algo = list->num_algo;
706 for (i = 0; i < list->num_algo; i++)
707 new_list->hmac[i] = list->hmac[i];
708 return (new_list);
709 }
710
711 sctp_hmaclist_t *
712 sctp_default_supported_hmaclist(void)
713 {
714 sctp_hmaclist_t *new_list;
715
716 new_list = sctp_alloc_hmaclist(2);
717 if (new_list == NULL)
718 return (NULL);
719 /* We prefer SHA256, so list it first */
720 (void)sctp_auth_add_hmacid(new_list, SCTP_AUTH_HMAC_ID_SHA256);
721 (void)sctp_auth_add_hmacid(new_list, SCTP_AUTH_HMAC_ID_SHA1);
722 return (new_list);
723 }
724
725 /*-
726 * HMAC algos are listed in priority/preference order
727 * find the best HMAC id to use for the peer based on local support
728 */
729 uint16_t
730 sctp_negotiate_hmacid(sctp_hmaclist_t *peer, sctp_hmaclist_t *local)
731 {
732 int i, j;
733
734 if ((local == NULL) || (peer == NULL))
735 return (SCTP_AUTH_HMAC_ID_RSVD);
736
737 for (i = 0; i < peer->num_algo; i++) {
738 for (j = 0; j < local->num_algo; j++) {
739 if (peer->hmac[i] == local->hmac[j]) {
740 /* found the "best" one */
741 SCTPDBG(SCTP_DEBUG_AUTH1,
742 "SCTP: negotiated peer HMAC id %u\n",
743 peer->hmac[i]);
744 return (peer->hmac[i]);
745 }
746 }
747 }
748 /* didn't find one! */
749 return (SCTP_AUTH_HMAC_ID_RSVD);
750 }
751
752 /*-
753 * serialize the HMAC algo list and return space used
754 * caller must guarantee ptr has appropriate space
755 */
756 int
757 sctp_serialize_hmaclist(sctp_hmaclist_t *list, uint8_t *ptr)
758 {
759 int i;
760 uint16_t hmac_id;
761
762 if (list == NULL)
763 return (0);
764
765 for (i = 0; i < list->num_algo; i++) {
766 hmac_id = htons(list->hmac[i]);
767 memcpy(ptr, &hmac_id, sizeof(hmac_id));
768 ptr += sizeof(hmac_id);
769 }
770 return (list->num_algo * sizeof(hmac_id));
771 }
772
773 int
774 sctp_verify_hmac_param(struct sctp_auth_hmac_algo *hmacs, uint32_t num_hmacs)
775 {
776 uint32_t i;
777
778 for (i = 0; i < num_hmacs; i++) {
779 if (ntohs(hmacs->hmac_ids[i]) == SCTP_AUTH_HMAC_ID_SHA1) {
780 return (0);
781 }
782 }
783 return (-1);
784 }
785
786 sctp_authinfo_t *
787 sctp_alloc_authinfo(void)
788 {
789 sctp_authinfo_t *new_authinfo;
790
791 SCTP_MALLOC(new_authinfo, sctp_authinfo_t *, sizeof(*new_authinfo),
792 SCTP_M_AUTH_IF);
793
794 if (new_authinfo == NULL) {
795 /* out of memory */
796 return (NULL);
797 }
798 memset(new_authinfo, 0, sizeof(*new_authinfo));
799 return (new_authinfo);
800 }
801
802 void
803 sctp_free_authinfo(sctp_authinfo_t *authinfo)
804 {
805 if (authinfo == NULL)
806 return;
807
808 if (authinfo->random != NULL)
809 sctp_free_key(authinfo->random);
810 if (authinfo->peer_random != NULL)
811 sctp_free_key(authinfo->peer_random);
812 if (authinfo->assoc_key != NULL)
813 sctp_free_key(authinfo->assoc_key);
814 if (authinfo->recv_key != NULL)
815 sctp_free_key(authinfo->recv_key);
816
817 /* We are NOT dynamically allocating authinfo's right now... */
818 /* SCTP_FREE(authinfo, SCTP_M_AUTH_??); */
819 }
820
821
822 uint32_t
823 sctp_get_auth_chunk_len(uint16_t hmac_algo)
824 {
825 int size;
826
827 size = sizeof(struct sctp_auth_chunk) + sctp_get_hmac_digest_len(hmac_algo);
828 return (SCTP_SIZE32(size));
829 }
830
831 uint32_t
832 sctp_get_hmac_digest_len(uint16_t hmac_algo)
833 {
834 switch (hmac_algo) {
835 case SCTP_AUTH_HMAC_ID_SHA1:
836 return (SCTP_AUTH_DIGEST_LEN_SHA1);
837 case SCTP_AUTH_HMAC_ID_SHA256:
838 return (SCTP_AUTH_DIGEST_LEN_SHA256);
839 default:
840 /* unknown HMAC algorithm: can't do anything */
841 return (0);
842 } /* end switch */
843 }
844
845 static inline int
846 sctp_get_hmac_block_len(uint16_t hmac_algo)
847 {
848 switch (hmac_algo) {
849 case SCTP_AUTH_HMAC_ID_SHA1:
850 return (64);
851 case SCTP_AUTH_HMAC_ID_SHA256:
852 return (64);
853 case SCTP_AUTH_HMAC_ID_RSVD:
854 default:
855 /* unknown HMAC algorithm: can't do anything */
856 return (0);
857 } /* end switch */
858 }
859
860 static void
861 sctp_hmac_init(uint16_t hmac_algo, sctp_hash_context_t *ctx)
862 {
863 switch (hmac_algo) {
864 case SCTP_AUTH_HMAC_ID_SHA1:
865 SCTP_SHA1_INIT(&ctx->sha1);
866 break;
867 case SCTP_AUTH_HMAC_ID_SHA256:
868 SCTP_SHA256_INIT(&ctx->sha256);
869 break;
870 case SCTP_AUTH_HMAC_ID_RSVD:
871 default:
872 /* unknown HMAC algorithm: can't do anything */
873 return;
874 } /* end switch */
875 }
876
877 static void
878 sctp_hmac_update(uint16_t hmac_algo, sctp_hash_context_t *ctx,
879 uint8_t *text, uint32_t textlen)
880 {
881 switch (hmac_algo) {
882 case SCTP_AUTH_HMAC_ID_SHA1:
883 SCTP_SHA1_UPDATE(&ctx->sha1, text, textlen);
884 break;
885 case SCTP_AUTH_HMAC_ID_SHA256:
886 SCTP_SHA256_UPDATE(&ctx->sha256, text, textlen);
887 break;
888 case SCTP_AUTH_HMAC_ID_RSVD:
889 default:
890 /* unknown HMAC algorithm: can't do anything */
891 return;
892 } /* end switch */
893 }
894
895 static void
896 sctp_hmac_final(uint16_t hmac_algo, sctp_hash_context_t *ctx,
897 uint8_t *digest)
898 {
899 switch (hmac_algo) {
900 case SCTP_AUTH_HMAC_ID_SHA1:
901 SCTP_SHA1_FINAL(digest, &ctx->sha1);
902 break;
903 case SCTP_AUTH_HMAC_ID_SHA256:
904 SCTP_SHA256_FINAL(digest, &ctx->sha256);
905 break;
906 case SCTP_AUTH_HMAC_ID_RSVD:
907 default:
908 /* unknown HMAC algorithm: can't do anything */
909 return;
910 } /* end switch */
911 }
912
913 /*-
914 * Keyed-Hashing for Message Authentication: FIPS 198 (RFC 2104)
915 *
916 * Compute the HMAC digest using the desired hash key, text, and HMAC
917 * algorithm. Resulting digest is placed in 'digest' and digest length
918 * is returned, if the HMAC was performed.
919 *
920 * WARNING: it is up to the caller to supply sufficient space to hold the
921 * resultant digest.
922 */
923 uint32_t
924 sctp_hmac(uint16_t hmac_algo, uint8_t *key, uint32_t keylen,
925 uint8_t *text, uint32_t textlen, uint8_t *digest)
926 {
927 uint32_t digestlen;
928 uint32_t blocklen;
929 sctp_hash_context_t ctx;
930 uint8_t ipad[128], opad[128]; /* keyed hash inner/outer pads */
931 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
932 uint32_t i;
933
934 /* sanity check the material and length */
935 if ((key == NULL) || (keylen == 0) || (text == NULL) ||
936 (textlen == 0) || (digest == NULL)) {
937 /* can't do HMAC with empty key or text or digest store */
938 return (0);
939 }
940 /* validate the hmac algo and get the digest length */
941 digestlen = sctp_get_hmac_digest_len(hmac_algo);
942 if (digestlen == 0)
943 return (0);
944
945 /* hash the key if it is longer than the hash block size */
946 blocklen = sctp_get_hmac_block_len(hmac_algo);
947 if (keylen > blocklen) {
948 sctp_hmac_init(hmac_algo, &ctx);
949 sctp_hmac_update(hmac_algo, &ctx, key, keylen);
950 sctp_hmac_final(hmac_algo, &ctx, temp);
951 /* set the hashed key as the key */
952 keylen = digestlen;
953 key = temp;
954 }
955 /* initialize the inner/outer pads with the key and "append" zeroes */
956 memset(ipad, 0, blocklen);
957 memset(opad, 0, blocklen);
958 memcpy(ipad, key, keylen);
959 memcpy(opad, key, keylen);
960
961 /* XOR the key with ipad and opad values */
962 for (i = 0; i < blocklen; i++) {
963 ipad[i] ^= 0x36;
964 opad[i] ^= 0x5c;
965 }
966
967 /* perform inner hash */
968 sctp_hmac_init(hmac_algo, &ctx);
969 sctp_hmac_update(hmac_algo, &ctx, ipad, blocklen);
970 sctp_hmac_update(hmac_algo, &ctx, text, textlen);
971 sctp_hmac_final(hmac_algo, &ctx, temp);
972
973 /* perform outer hash */
974 sctp_hmac_init(hmac_algo, &ctx);
975 sctp_hmac_update(hmac_algo, &ctx, opad, blocklen);
976 sctp_hmac_update(hmac_algo, &ctx, temp, digestlen);
977 sctp_hmac_final(hmac_algo, &ctx, digest);
978
979 return (digestlen);
980 }
981
982 /* mbuf version */
983 uint32_t
984 sctp_hmac_m(uint16_t hmac_algo, uint8_t *key, uint32_t keylen,
985 struct mbuf *m, uint32_t m_offset, uint8_t *digest, uint32_t trailer)
986 {
987 uint32_t digestlen;
988 uint32_t blocklen;
989 sctp_hash_context_t ctx;
990 uint8_t ipad[128], opad[128]; /* keyed hash inner/outer pads */
991 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
992 uint32_t i;
993 struct mbuf *m_tmp;
994
995 /* sanity check the material and length */
996 if ((key == NULL) || (keylen == 0) || (m == NULL) || (digest == NULL)) {
997 /* can't do HMAC with empty key or text or digest store */
998 return (0);
999 }
1000 /* validate the hmac algo and get the digest length */
1001 digestlen = sctp_get_hmac_digest_len(hmac_algo);
1002 if (digestlen == 0)
1003 return (0);
1004
1005 /* hash the key if it is longer than the hash block size */
1006 blocklen = sctp_get_hmac_block_len(hmac_algo);
1007 if (keylen > blocklen) {
1008 sctp_hmac_init(hmac_algo, &ctx);
1009 sctp_hmac_update(hmac_algo, &ctx, key, keylen);
1010 sctp_hmac_final(hmac_algo, &ctx, temp);
1011 /* set the hashed key as the key */
1012 keylen = digestlen;
1013 key = temp;
1014 }
1015 /* initialize the inner/outer pads with the key and "append" zeroes */
1016 memset(ipad, 0, blocklen);
1017 memset(opad, 0, blocklen);
1018 memcpy(ipad, key, keylen);
1019 memcpy(opad, key, keylen);
1020
1021 /* XOR the key with ipad and opad values */
1022 for (i = 0; i < blocklen; i++) {
1023 ipad[i] ^= 0x36;
1024 opad[i] ^= 0x5c;
1025 }
1026
1027 /* perform inner hash */
1028 sctp_hmac_init(hmac_algo, &ctx);
1029 sctp_hmac_update(hmac_algo, &ctx, ipad, blocklen);
1030 /* find the correct starting mbuf and offset (get start of text) */
1031 m_tmp = m;
1032 while ((m_tmp != NULL) && (m_offset >= (uint32_t)SCTP_BUF_LEN(m_tmp))) {
1033 m_offset -= SCTP_BUF_LEN(m_tmp);
1034 m_tmp = SCTP_BUF_NEXT(m_tmp);
1035 }
1036 /* now use the rest of the mbuf chain for the text */
1037 while (m_tmp != NULL) {
1038 if ((SCTP_BUF_NEXT(m_tmp) == NULL) && trailer) {
1039 sctp_hmac_update(hmac_algo, &ctx, mtod(m_tmp, uint8_t *)+m_offset,
1040 SCTP_BUF_LEN(m_tmp) - (trailer + m_offset));
1041 } else {
1042 sctp_hmac_update(hmac_algo, &ctx, mtod(m_tmp, uint8_t *)+m_offset,
1043 SCTP_BUF_LEN(m_tmp) - m_offset);
1044 }
1045
1046 /* clear the offset since it's only for the first mbuf */
1047 m_offset = 0;
1048 m_tmp = SCTP_BUF_NEXT(m_tmp);
1049 }
1050 sctp_hmac_final(hmac_algo, &ctx, temp);
1051
1052 /* perform outer hash */
1053 sctp_hmac_init(hmac_algo, &ctx);
1054 sctp_hmac_update(hmac_algo, &ctx, opad, blocklen);
1055 sctp_hmac_update(hmac_algo, &ctx, temp, digestlen);
1056 sctp_hmac_final(hmac_algo, &ctx, digest);
1057
1058 return (digestlen);
1059 }
1060
1061 /*-
1062 * verify the HMAC digest using the desired hash key, text, and HMAC
1063 * algorithm.
1064 * Returns -1 on error, 0 on success.
1065 */
1066 int
1067 sctp_verify_hmac(uint16_t hmac_algo, uint8_t *key, uint32_t keylen,
1068 uint8_t *text, uint32_t textlen,
1069 uint8_t *digest, uint32_t digestlen)
1070 {
1071 uint32_t len;
1072 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
1073
1074 /* sanity check the material and length */
1075 if ((key == NULL) || (keylen == 0) ||
1076 (text == NULL) || (textlen == 0) || (digest == NULL)) {
1077 /* can't do HMAC with empty key or text or digest */
1078 return (-1);
1079 }
1080 len = sctp_get_hmac_digest_len(hmac_algo);
1081 if ((len == 0) || (digestlen != len))
1082 return (-1);
1083
1084 /* compute the expected hash */
1085 if (sctp_hmac(hmac_algo, key, keylen, text, textlen, temp) != len)
1086 return (-1);
1087
1088 if (memcmp(digest, temp, digestlen) != 0)
1089 return (-1);
1090 else
1091 return (0);
1092 }
1093
1094
1095 /*
1096 * computes the requested HMAC using a key struct (which may be modified if
1097 * the keylen exceeds the HMAC block len).
1098 */
1099 uint32_t
1100 sctp_compute_hmac(uint16_t hmac_algo, sctp_key_t *key, uint8_t *text,
1101 uint32_t textlen, uint8_t *digest)
1102 {
1103 uint32_t digestlen;
1104 uint32_t blocklen;
1105 sctp_hash_context_t ctx;
1106 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
1107
1108 /* sanity check */
1109 if ((key == NULL) || (text == NULL) || (textlen == 0) ||
1110 (digest == NULL)) {
1111 /* can't do HMAC with empty key or text or digest store */
1112 return (0);
1113 }
1114 /* validate the hmac algo and get the digest length */
1115 digestlen = sctp_get_hmac_digest_len(hmac_algo);
1116 if (digestlen == 0)
1117 return (0);
1118
1119 /* hash the key if it is longer than the hash block size */
1120 blocklen = sctp_get_hmac_block_len(hmac_algo);
1121 if (key->keylen > blocklen) {
1122 sctp_hmac_init(hmac_algo, &ctx);
1123 sctp_hmac_update(hmac_algo, &ctx, key->key, key->keylen);
1124 sctp_hmac_final(hmac_algo, &ctx, temp);
1125 /* save the hashed key as the new key */
1126 key->keylen = digestlen;
1127 memcpy(key->key, temp, key->keylen);
1128 }
1129 return (sctp_hmac(hmac_algo, key->key, key->keylen, text, textlen,
1130 digest));
1131 }
1132
1133 /* mbuf version */
1134 uint32_t
1135 sctp_compute_hmac_m(uint16_t hmac_algo, sctp_key_t *key, struct mbuf *m,
1136 uint32_t m_offset, uint8_t *digest)
1137 {
1138 uint32_t digestlen;
1139 uint32_t blocklen;
1140 sctp_hash_context_t ctx;
1141 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
1142
1143 /* sanity check */
1144 if ((key == NULL) || (m == NULL) || (digest == NULL)) {
1145 /* can't do HMAC with empty key or text or digest store */
1146 return (0);
1147 }
1148 /* validate the hmac algo and get the digest length */
1149 digestlen = sctp_get_hmac_digest_len(hmac_algo);
1150 if (digestlen == 0)
1151 return (0);
1152
1153 /* hash the key if it is longer than the hash block size */
1154 blocklen = sctp_get_hmac_block_len(hmac_algo);
1155 if (key->keylen > blocklen) {
1156 sctp_hmac_init(hmac_algo, &ctx);
1157 sctp_hmac_update(hmac_algo, &ctx, key->key, key->keylen);
1158 sctp_hmac_final(hmac_algo, &ctx, temp);
1159 /* save the hashed key as the new key */
1160 key->keylen = digestlen;
1161 memcpy(key->key, temp, key->keylen);
1162 }
1163 return (sctp_hmac_m(hmac_algo, key->key, key->keylen, m, m_offset, digest, 0));
1164 }
1165
1166 int
1167 sctp_auth_is_supported_hmac(sctp_hmaclist_t *list, uint16_t id)
1168 {
1169 int i;
1170
1171 if ((list == NULL) || (id == SCTP_AUTH_HMAC_ID_RSVD))
1172 return (0);
1173
1174 for (i = 0; i < list->num_algo; i++)
1175 if (list->hmac[i] == id)
1176 return (1);
1177
1178 /* not in the list */
1179 return (0);
1180 }
1181
1182
1183 /*-
1184 * clear any cached key(s) if they match the given key id on an association.
1185 * the cached key(s) will be recomputed and re-cached at next use.
1186 * ASSUMES TCB_LOCK is already held
1187 */
1188 void
1189 sctp_clear_cachedkeys(struct sctp_tcb *stcb, uint16_t keyid)
1190 {
1191 if (stcb == NULL)
1192 return;
1193
1194 if (keyid == stcb->asoc.authinfo.assoc_keyid) {
1195 sctp_free_key(stcb->asoc.authinfo.assoc_key);
1196 stcb->asoc.authinfo.assoc_key = NULL;
1197 }
1198 if (keyid == stcb->asoc.authinfo.recv_keyid) {
1199 sctp_free_key(stcb->asoc.authinfo.recv_key);
1200 stcb->asoc.authinfo.recv_key = NULL;
1201 }
1202 }
1203
1204 /*-
1205 * clear any cached key(s) if they match the given key id for all assocs on
1206 * an endpoint.
1207 * ASSUMES INP_WLOCK is already held
1208 */
1209 void
1210 sctp_clear_cachedkeys_ep(struct sctp_inpcb *inp, uint16_t keyid)
1211 {
1212 struct sctp_tcb *stcb;
1213
1214 if (inp == NULL)
1215 return;
1216
1217 /* clear the cached keys on all assocs on this instance */
1218 LIST_FOREACH(stcb, &inp->sctp_asoc_list, sctp_tcblist) {
1219 SCTP_TCB_LOCK(stcb);
1220 sctp_clear_cachedkeys(stcb, keyid);
1221 SCTP_TCB_UNLOCK(stcb);
1222 }
1223 }
1224
1225 /*-
1226 * delete a shared key from an association
1227 * ASSUMES TCB_LOCK is already held
1228 */
1229 int
1230 sctp_delete_sharedkey(struct sctp_tcb *stcb, uint16_t keyid)
1231 {
1232 sctp_sharedkey_t *skey;
1233
1234 if (stcb == NULL)
1235 return (-1);
1236
1237 /* is the keyid the assoc active sending key */
1238 if (keyid == stcb->asoc.authinfo.active_keyid)
1239 return (-1);
1240
1241 /* does the key exist? */
1242 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
1243 if (skey == NULL)
1244 return (-1);
1245
1246 /* are there other refcount holders on the key? */
1247 if (skey->refcount > 1)
1248 return (-1);
1249
1250 /* remove it */
1251 LIST_REMOVE(skey, next);
1252 sctp_free_sharedkey(skey); /* frees skey->key as well */
1253
1254 /* clear any cached keys */
1255 sctp_clear_cachedkeys(stcb, keyid);
1256 return (0);
1257 }
1258
1259 /*-
1260 * deletes a shared key from the endpoint
1261 * ASSUMES INP_WLOCK is already held
1262 */
1263 int
1264 sctp_delete_sharedkey_ep(struct sctp_inpcb *inp, uint16_t keyid)
1265 {
1266 sctp_sharedkey_t *skey;
1267
1268 if (inp == NULL)
1269 return (-1);
1270
1271 /* is the keyid the active sending key on the endpoint */
1272 if (keyid == inp->sctp_ep.default_keyid)
1273 return (-1);
1274
1275 /* does the key exist? */
1276 skey = sctp_find_sharedkey(&inp->sctp_ep.shared_keys, keyid);
1277 if (skey == NULL)
1278 return (-1);
1279
1280 /* endpoint keys are not refcounted */
1281
1282 /* remove it */
1283 LIST_REMOVE(skey, next);
1284 sctp_free_sharedkey(skey); /* frees skey->key as well */
1285
1286 /* clear any cached keys */
1287 sctp_clear_cachedkeys_ep(inp, keyid);
1288 return (0);
1289 }
1290
1291 /*-
1292 * set the active key on an association
1293 * ASSUMES TCB_LOCK is already held
1294 */
1295 int
1296 sctp_auth_setactivekey(struct sctp_tcb *stcb, uint16_t keyid)
1297 {
1298 sctp_sharedkey_t *skey = NULL;
1299
1300 /* find the key on the assoc */
1301 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
1302 if (skey == NULL) {
1303 /* that key doesn't exist */
1304 return (-1);
1305 }
1306 if ((skey->deactivated) && (skey->refcount > 1)) {
1307 /* can't reactivate a deactivated key with other refcounts */
1308 return (-1);
1309 }
1310 /* set the (new) active key */
1311 stcb->asoc.authinfo.active_keyid = keyid;
1312 /* reset the deactivated flag */
1313 skey->deactivated = 0;
1314
1315 return (0);
1316 }
1317
1318 /*-
1319 * set the active key on an endpoint
1320 * ASSUMES INP_WLOCK is already held
1321 */
1322 int
1323 sctp_auth_setactivekey_ep(struct sctp_inpcb *inp, uint16_t keyid)
1324 {
1325 sctp_sharedkey_t *skey;
1326
1327 /* find the key */
1328 skey = sctp_find_sharedkey(&inp->sctp_ep.shared_keys, keyid);
1329 if (skey == NULL) {
1330 /* that key doesn't exist */
1331 return (-1);
1332 }
1333 inp->sctp_ep.default_keyid = keyid;
1334 return (0);
1335 }
1336
1337 /*-
1338 * deactivates a shared key from the association
1339 * ASSUMES INP_WLOCK is already held
1340 */
1341 int
1342 sctp_deact_sharedkey(struct sctp_tcb *stcb, uint16_t keyid)
1343 {
1344 sctp_sharedkey_t *skey;
1345
1346 if (stcb == NULL)
1347 return (-1);
1348
1349 /* is the keyid the assoc active sending key */
1350 if (keyid == stcb->asoc.authinfo.active_keyid)
1351 return (-1);
1352
1353 /* does the key exist? */
1354 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
1355 if (skey == NULL)
1356 return (-1);
1357
1358 /* are there other refcount holders on the key? */
1359 if (skey->refcount == 1) {
1360 /* no other users, send a notification for this key */
1361 sctp_ulp_notify(SCTP_NOTIFY_AUTH_FREE_KEY, stcb, keyid, 0,
1362 SCTP_SO_LOCKED);
1363 }
1364 /* mark the key as deactivated */
1365 skey->deactivated = 1;
1366
1367 return (0);
1368 }
1369
1370 /*-
1371 * deactivates a shared key from the endpoint
1372 * ASSUMES INP_WLOCK is already held
1373 */
1374 int
1375 sctp_deact_sharedkey_ep(struct sctp_inpcb *inp, uint16_t keyid)
1376 {
1377 sctp_sharedkey_t *skey;
1378
1379 if (inp == NULL)
1380 return (-1);
1381
1382 /* is the keyid the active sending key on the endpoint */
1383 if (keyid == inp->sctp_ep.default_keyid)
1384 return (-1);
1385
1386 /* does the key exist? */
1387 skey = sctp_find_sharedkey(&inp->sctp_ep.shared_keys, keyid);
1388 if (skey == NULL)
1389 return (-1);
1390
1391 /* endpoint keys are not refcounted */
1392
1393 /* remove it */
1394 LIST_REMOVE(skey, next);
1395 sctp_free_sharedkey(skey); /* frees skey->key as well */
1396
1397 return (0);
1398 }
1399
1400 /*
1401 * get local authentication parameters from cookie (from INIT-ACK)
1402 */
1403 void
1404 sctp_auth_get_cookie_params(struct sctp_tcb *stcb, struct mbuf *m,
1405 uint32_t offset, uint32_t length)
1406 {
1407 struct sctp_paramhdr *phdr, tmp_param;
1408 uint16_t plen, ptype;
1409 uint8_t random_store[SCTP_PARAM_BUFFER_SIZE];
1410 struct sctp_auth_random *p_random = NULL;
1411 uint16_t random_len = 0;
1412 uint8_t hmacs_store[SCTP_PARAM_BUFFER_SIZE];
1413 struct sctp_auth_hmac_algo *hmacs = NULL;
1414 uint16_t hmacs_len = 0;
1415 uint8_t chunks_store[SCTP_PARAM_BUFFER_SIZE];
1416 struct sctp_auth_chunk_list *chunks = NULL;
1417 uint16_t num_chunks = 0;
1418 sctp_key_t *new_key;
1419 uint32_t keylen;
1420
1421 /* convert to upper bound */
1422 length += offset;
1423
1424 phdr = (struct sctp_paramhdr *)sctp_m_getptr(m, offset,
1425 sizeof(struct sctp_paramhdr), (uint8_t *)&tmp_param);
1426 while (phdr != NULL) {
1427 ptype = ntohs(phdr->param_type);
1428 plen = ntohs(phdr->param_length);
1429
1430 if ((plen == 0) || (offset + plen > length))
1431 break;
1432
1433 if (ptype == SCTP_RANDOM) {
1434 if (plen > sizeof(random_store))
1435 break;
1436 phdr = sctp_get_next_param(m, offset,
1437 (struct sctp_paramhdr *)random_store, plen);
1438 if (phdr == NULL)
1439 return;
1440 /* save the random and length for the key */
1441 p_random = (struct sctp_auth_random *)phdr;
1442 random_len = plen - sizeof(*p_random);
1443 } else if (ptype == SCTP_HMAC_LIST) {
1444 uint16_t num_hmacs;
1445 uint16_t i;
1446
1447 if (plen > sizeof(hmacs_store))
1448 break;
1449 phdr = sctp_get_next_param(m, offset,
1450 (struct sctp_paramhdr *)hmacs_store, plen);
1451 if (phdr == NULL)
1452 return;
1453 /* save the hmacs list and num for the key */
1454 hmacs = (struct sctp_auth_hmac_algo *)phdr;
1455 hmacs_len = plen - sizeof(*hmacs);
1456 num_hmacs = hmacs_len / sizeof(hmacs->hmac_ids[0]);
1457 if (stcb->asoc.local_hmacs != NULL)
1458 sctp_free_hmaclist(stcb->asoc.local_hmacs);
1459 stcb->asoc.local_hmacs = sctp_alloc_hmaclist(num_hmacs);
1460 if (stcb->asoc.local_hmacs != NULL) {
1461 for (i = 0; i < num_hmacs; i++) {
1462 (void)sctp_auth_add_hmacid(stcb->asoc.local_hmacs,
1463 ntohs(hmacs->hmac_ids[i]));
1464 }
1465 }
1466 } else if (ptype == SCTP_CHUNK_LIST) {
1467 int i;
1468
1469 if (plen > sizeof(chunks_store))
1470 break;
1471 phdr = sctp_get_next_param(m, offset,
1472 (struct sctp_paramhdr *)chunks_store, plen);
1473 if (phdr == NULL)
1474 return;
1475 chunks = (struct sctp_auth_chunk_list *)phdr;
1476 num_chunks = plen - sizeof(*chunks);
1477 /* save chunks list and num for the key */
1478 if (stcb->asoc.local_auth_chunks != NULL)
1479 sctp_clear_chunklist(stcb->asoc.local_auth_chunks);
1480 else
1481 stcb->asoc.local_auth_chunks = sctp_alloc_chunklist();
1482 for (i = 0; i < num_chunks; i++) {
1483 (void)sctp_auth_add_chunk(chunks->chunk_types[i],
1484 stcb->asoc.local_auth_chunks);
1485 }
1486 }
1487 /* get next parameter */
1488 offset += SCTP_SIZE32(plen);
1489 if (offset + sizeof(struct sctp_paramhdr) > length)
1490 break;
1491 phdr = (struct sctp_paramhdr *)sctp_m_getptr(m, offset, sizeof(struct sctp_paramhdr),
1492 (uint8_t *)&tmp_param);
1493 }
1494 /* concatenate the full random key */
1495 keylen = sizeof(*p_random) + random_len + sizeof(*hmacs) + hmacs_len;
1496 if (chunks != NULL) {
1497 keylen += sizeof(*chunks) + num_chunks;
1498 }
1499 new_key = sctp_alloc_key(keylen);
1500 if (new_key != NULL) {
1501 /* copy in the RANDOM */
1502 if (p_random != NULL) {
1503 keylen = sizeof(*p_random) + random_len;
1504 memcpy(new_key->key, p_random, keylen);
1505 } else {
1506 keylen = 0;
1507 }
1508 /* append in the AUTH chunks */
1509 if (chunks != NULL) {
1510 memcpy(new_key->key + keylen, chunks,
1511 sizeof(*chunks) + num_chunks);
1512 keylen += sizeof(*chunks) + num_chunks;
1513 }
1514 /* append in the HMACs */
1515 if (hmacs != NULL) {
1516 memcpy(new_key->key + keylen, hmacs,
1517 sizeof(*hmacs) + hmacs_len);
1518 }
1519 }
1520 if (stcb->asoc.authinfo.random != NULL)
1521 sctp_free_key(stcb->asoc.authinfo.random);
1522 stcb->asoc.authinfo.random = new_key;
1523 stcb->asoc.authinfo.random_len = random_len;
1524 sctp_clear_cachedkeys(stcb, stcb->asoc.authinfo.assoc_keyid);
1525 sctp_clear_cachedkeys(stcb, stcb->asoc.authinfo.recv_keyid);
1526
1527 /* negotiate what HMAC to use for the peer */
1528 stcb->asoc.peer_hmac_id = sctp_negotiate_hmacid(stcb->asoc.peer_hmacs,
1529 stcb->asoc.local_hmacs);
1530
1531 /* copy defaults from the endpoint */
1532 /* FIX ME: put in cookie? */
1533 stcb->asoc.authinfo.active_keyid = stcb->sctp_ep->sctp_ep.default_keyid;
1534 /* copy out the shared key list (by reference) from the endpoint */
1535 (void)sctp_copy_skeylist(&stcb->sctp_ep->sctp_ep.shared_keys,
1536 &stcb->asoc.shared_keys);
1537 }
1538
1539 /*
1540 * compute and fill in the HMAC digest for a packet
1541 */
1542 void
1543 sctp_fill_hmac_digest_m(struct mbuf *m, uint32_t auth_offset,
1544 struct sctp_auth_chunk *auth, struct sctp_tcb *stcb, uint16_t keyid)
1545 {
1546 uint32_t digestlen;
1547 sctp_sharedkey_t *skey;
1548 sctp_key_t *key;
1549
1550 if ((stcb == NULL) || (auth == NULL))
1551 return;
1552
1553 /* zero the digest + chunk padding */
1554 digestlen = sctp_get_hmac_digest_len(stcb->asoc.peer_hmac_id);
1555 memset(auth->hmac, 0, SCTP_SIZE32(digestlen));
1556
1557 /* is the desired key cached? */
1558 if ((keyid != stcb->asoc.authinfo.assoc_keyid) ||
1559 (stcb->asoc.authinfo.assoc_key == NULL)) {
1560 if (stcb->asoc.authinfo.assoc_key != NULL) {
1561 /* free the old cached key */
1562 sctp_free_key(stcb->asoc.authinfo.assoc_key);
1563 }
1564 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
1565 /* the only way skey is NULL is if null key id 0 is used */
1566 if (skey != NULL)
1567 key = skey->key;
1568 else
1569 key = NULL;
1570 /* compute a new assoc key and cache it */
1571 stcb->asoc.authinfo.assoc_key =
1572 sctp_compute_hashkey(stcb->asoc.authinfo.random,
1573 stcb->asoc.authinfo.peer_random, key);
1574 stcb->asoc.authinfo.assoc_keyid = keyid;
1575 SCTPDBG(SCTP_DEBUG_AUTH1, "caching key id %u\n",
1576 stcb->asoc.authinfo.assoc_keyid);
1577 #ifdef SCTP_DEBUG
1578 if (SCTP_AUTH_DEBUG)
1579 sctp_print_key(stcb->asoc.authinfo.assoc_key,
1580 "Assoc Key");
1581 #endif
1582 }
1583 /* set in the active key id */
1584 auth->shared_key_id = htons(keyid);
1585
1586 /* compute and fill in the digest */
1587 (void)sctp_compute_hmac_m(stcb->asoc.peer_hmac_id, stcb->asoc.authinfo.assoc_key,
1588 m, auth_offset, auth->hmac);
1589 }
1590
1591
1592 static void
1593 sctp_zero_m(struct mbuf *m, uint32_t m_offset, uint32_t size)
1594 {
1595 struct mbuf *m_tmp;
1596 uint8_t *data;
1597
1598 /* sanity check */
1599 if (m == NULL)
1600 return;
1601
1602 /* find the correct starting mbuf and offset (get start position) */
1603 m_tmp = m;
1604 while ((m_tmp != NULL) && (m_offset >= (uint32_t)SCTP_BUF_LEN(m_tmp))) {
1605 m_offset -= SCTP_BUF_LEN(m_tmp);
1606 m_tmp = SCTP_BUF_NEXT(m_tmp);
1607 }
1608 /* now use the rest of the mbuf chain */
1609 while ((m_tmp != NULL) && (size > 0)) {
1610 data = mtod(m_tmp, uint8_t *)+m_offset;
1611 if (size > (uint32_t)(SCTP_BUF_LEN(m_tmp) - m_offset)) {
1612 memset(data, 0, SCTP_BUF_LEN(m_tmp) - m_offset);
1613 size -= SCTP_BUF_LEN(m_tmp) - m_offset;
1614 } else {
1615 memset(data, 0, size);
1616 size = 0;
1617 }
1618 /* clear the offset since it's only for the first mbuf */
1619 m_offset = 0;
1620 m_tmp = SCTP_BUF_NEXT(m_tmp);
1621 }
1622 }
1623
1624 /*-
1625 * process the incoming Authentication chunk
1626 * return codes:
1627 * -1 on any authentication error
1628 * 0 on authentication verification
1629 */
1630 int
1631 sctp_handle_auth(struct sctp_tcb *stcb, struct sctp_auth_chunk *auth,
1632 struct mbuf *m, uint32_t offset)
1633 {
1634 uint16_t chunklen;
1635 uint16_t shared_key_id;
1636 uint16_t hmac_id;
1637 sctp_sharedkey_t *skey;
1638 uint32_t digestlen;
1639 uint8_t digest[SCTP_AUTH_DIGEST_LEN_MAX];
1640 uint8_t computed_digest[SCTP_AUTH_DIGEST_LEN_MAX];
1641
1642 /* auth is checked for NULL by caller */
1643 chunklen = ntohs(auth->ch.chunk_length);
1644 if (chunklen < sizeof(*auth)) {
1645 SCTP_STAT_INCR(sctps_recvauthfailed);
1646 return (-1);
1647 }
1648 SCTP_STAT_INCR(sctps_recvauth);
1649
1650 /* get the auth params */
1651 shared_key_id = ntohs(auth->shared_key_id);
1652 hmac_id = ntohs(auth->hmac_id);
1653 SCTPDBG(SCTP_DEBUG_AUTH1,
1654 "SCTP AUTH Chunk: shared key %u, HMAC id %u\n",
1655 shared_key_id, hmac_id);
1656
1657 /* is the indicated HMAC supported? */
1658 if (!sctp_auth_is_supported_hmac(stcb->asoc.local_hmacs, hmac_id)) {
1659 struct mbuf *op_err;
1660 struct sctp_error_auth_invalid_hmac *cause;
1661
1662 SCTP_STAT_INCR(sctps_recvivalhmacid);
1663 SCTPDBG(SCTP_DEBUG_AUTH1,
1664 "SCTP Auth: unsupported HMAC id %u\n",
1665 hmac_id);
1666 /*
1667 * report this in an Error Chunk: Unsupported HMAC
1668 * Identifier
1669 */
1670 op_err = sctp_get_mbuf_for_msg(sizeof(struct sctp_error_auth_invalid_hmac),
1671 0, M_NOWAIT, 1, MT_HEADER);
1672 if (op_err != NULL) {
1673 /* pre-reserve some space */
1674 SCTP_BUF_RESV_UF(op_err, sizeof(struct sctp_chunkhdr));
1675 /* fill in the error */
1676 cause = mtod(op_err, struct sctp_error_auth_invalid_hmac *);
1677 cause->cause.code = htons(SCTP_CAUSE_UNSUPPORTED_HMACID);
1678 cause->cause.length = htons(sizeof(struct sctp_error_auth_invalid_hmac));
1679 cause->hmac_id = ntohs(hmac_id);
1680 SCTP_BUF_LEN(op_err) = sizeof(struct sctp_error_auth_invalid_hmac);
1681 /* queue it */
1682 sctp_queue_op_err(stcb, op_err);
1683 }
1684 return (-1);
1685 }
1686 /* get the indicated shared key, if available */
1687 if ((stcb->asoc.authinfo.recv_key == NULL) ||
1688 (stcb->asoc.authinfo.recv_keyid != shared_key_id)) {
1689 /* find the shared key on the assoc first */
1690 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys,
1691 shared_key_id);
1692 /* if the shared key isn't found, discard the chunk */
1693 if (skey == NULL) {
1694 SCTP_STAT_INCR(sctps_recvivalkeyid);
1695 SCTPDBG(SCTP_DEBUG_AUTH1,
1696 "SCTP Auth: unknown key id %u\n",
1697 shared_key_id);
1698 return (-1);
1699 }
1700 /* generate a notification if this is a new key id */
1701 if (stcb->asoc.authinfo.recv_keyid != shared_key_id)
1702 /*
1703 * sctp_ulp_notify(SCTP_NOTIFY_AUTH_NEW_KEY, stcb,
1704 * shared_key_id, (void
1705 * *)stcb->asoc.authinfo.recv_keyid);
1706 */
1707 sctp_notify_authentication(stcb, SCTP_AUTH_NEW_KEY,
1708 shared_key_id, stcb->asoc.authinfo.recv_keyid,
1709 SCTP_SO_NOT_LOCKED);
1710 /* compute a new recv assoc key and cache it */
1711 if (stcb->asoc.authinfo.recv_key != NULL)
1712 sctp_free_key(stcb->asoc.authinfo.recv_key);
1713 stcb->asoc.authinfo.recv_key =
1714 sctp_compute_hashkey(stcb->asoc.authinfo.random,
1715 stcb->asoc.authinfo.peer_random, skey->key);
1716 stcb->asoc.authinfo.recv_keyid = shared_key_id;
1717 #ifdef SCTP_DEBUG
1718 if (SCTP_AUTH_DEBUG)
1719 sctp_print_key(stcb->asoc.authinfo.recv_key, "Recv Key");
1720 #endif
1721 }
1722 /* validate the digest length */
1723 digestlen = sctp_get_hmac_digest_len(hmac_id);
1724 if (chunklen < (sizeof(*auth) + digestlen)) {
1725 /* invalid digest length */
1726 SCTP_STAT_INCR(sctps_recvauthfailed);
1727 SCTPDBG(SCTP_DEBUG_AUTH1,
1728 "SCTP Auth: chunk too short for HMAC\n");
1729 return (-1);
1730 }
1731 /* save a copy of the digest, zero the pseudo header, and validate */
1732 memcpy(digest, auth->hmac, digestlen);
1733 sctp_zero_m(m, offset + sizeof(*auth), SCTP_SIZE32(digestlen));
1734 (void)sctp_compute_hmac_m(hmac_id, stcb->asoc.authinfo.recv_key,
1735 m, offset, computed_digest);
1736
1737 /* compare the computed digest with the one in the AUTH chunk */
1738 if (memcmp(digest, computed_digest, digestlen) != 0) {
1739 SCTP_STAT_INCR(sctps_recvauthfailed);
1740 SCTPDBG(SCTP_DEBUG_AUTH1,
1741 "SCTP Auth: HMAC digest check failed\n");
1742 return (-1);
1743 }
1744 return (0);
1745 }
1746
1747 /*
1748 * Generate NOTIFICATION
1749 */
1750 void
1751 sctp_notify_authentication(struct sctp_tcb *stcb, uint32_t indication,
1752 uint16_t keyid, uint16_t alt_keyid, int so_locked
1753 #if !defined(__APPLE__) && !defined(SCTP_SO_LOCK_TESTING)
1754 SCTP_UNUSED
1755 #endif
1756 )
1757 {
1758 struct mbuf *m_notify;
1759 struct sctp_authkey_event *auth;
1760 struct sctp_queued_to_read *control;
1761
1762 if ((stcb == NULL) ||
1763 (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) ||
1764 (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_ALLGONE) ||
1765 (stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET)
1766 ) {
1767 /* If the socket is gone we are out of here */
1768 return;
1769 }
1770 if (sctp_stcb_is_feature_off(stcb->sctp_ep, stcb, SCTP_PCB_FLAGS_AUTHEVNT))
1771 /* event not enabled */
1772 return;
1773
1774 m_notify = sctp_get_mbuf_for_msg(sizeof(struct sctp_authkey_event),
1775 0, M_NOWAIT, 1, MT_HEADER);
1776 if (m_notify == NULL)
1777 /* no space left */
1778 return;
1779
1780 SCTP_BUF_LEN(m_notify) = 0;
1781 auth = mtod(m_notify, struct sctp_authkey_event *);
1782 memset(auth, 0, sizeof(struct sctp_authkey_event));
1783 auth->auth_type = SCTP_AUTHENTICATION_EVENT;
1784 auth->auth_flags = 0;
1785 auth->auth_length = sizeof(*auth);
1786 auth->auth_keynumber = keyid;
1787 auth->auth_altkeynumber = alt_keyid;
1788 auth->auth_indication = indication;
1789 auth->auth_assoc_id = sctp_get_associd(stcb);
1790
1791 SCTP_BUF_LEN(m_notify) = sizeof(*auth);
1792 SCTP_BUF_NEXT(m_notify) = NULL;
1793
1794 /* append to socket */
1795 control = sctp_build_readq_entry(stcb, stcb->asoc.primary_destination,
1796 0, 0, stcb->asoc.context, 0, 0, 0, m_notify);
1797 if (control == NULL) {
1798 /* no memory */
1799 sctp_m_freem(m_notify);
1800 return;
1801 }
1802 control->length = SCTP_BUF_LEN(m_notify);
1803 control->spec_flags = M_NOTIFICATION;
1804 /* not that we need this */
1805 control->tail_mbuf = m_notify;
1806 sctp_add_to_readq(stcb->sctp_ep, stcb, control,
1807 &stcb->sctp_socket->so_rcv, 1, SCTP_READ_LOCK_NOT_HELD, so_locked);
1808 }
1809
1810
1811 /*-
1812 * validates the AUTHentication related parameters in an INIT/INIT-ACK
1813 * Note: currently only used for INIT as INIT-ACK is handled inline
1814 * with sctp_load_addresses_from_init()
1815 */
1816 int
1817 sctp_validate_init_auth_params(struct mbuf *m, int offset, int limit)
1818 {
1819 struct sctp_paramhdr *phdr, param_buf;
1820 uint16_t ptype, plen;
1821 int peer_supports_asconf = 0;
1822 int peer_supports_auth = 0;
1823 int got_random = 0, got_hmacs = 0, got_chklist = 0;
1824 uint8_t saw_asconf = 0;
1825 uint8_t saw_asconf_ack = 0;
1826
1827 /* go through each of the params. */
1828 phdr = sctp_get_next_param(m, offset, ¶m_buf, sizeof(param_buf));
1829 while (phdr) {
1830 ptype = ntohs(phdr->param_type);
1831 plen = ntohs(phdr->param_length);
1832
1833 if (offset + plen > limit) {
1834 break;
1835 }
1836 if (plen < sizeof(struct sctp_paramhdr)) {
1837 break;
1838 }
1839 if (ptype == SCTP_SUPPORTED_CHUNK_EXT) {
1840 /* A supported extension chunk */
1841 struct sctp_supported_chunk_types_param *pr_supported;
1842 uint8_t local_store[SCTP_SMALL_CHUNK_STORE];
1843 int num_ent, i;
1844
1845 if (plen > sizeof(local_store)) {
1846 break;
1847 }
1848 phdr = sctp_get_next_param(m, offset,
1849 (struct sctp_paramhdr *)&local_store,
1850 plen);
1851 if (phdr == NULL) {
1852 return (-1);
1853 }
1854 pr_supported = (struct sctp_supported_chunk_types_param *)phdr;
1855 num_ent = plen - sizeof(struct sctp_paramhdr);
1856 for (i = 0; i < num_ent; i++) {
1857 switch (pr_supported->chunk_types[i]) {
1858 case SCTP_ASCONF:
1859 case SCTP_ASCONF_ACK:
1860 peer_supports_asconf = 1;
1861 break;
1862 default:
1863 /* one we don't care about */
1864 break;
1865 }
1866 }
1867 } else if (ptype == SCTP_RANDOM) {
1868 /* enforce the random length */
1869 if (plen != (sizeof(struct sctp_auth_random) +
1870 SCTP_AUTH_RANDOM_SIZE_REQUIRED)) {
1871 SCTPDBG(SCTP_DEBUG_AUTH1,
1872 "SCTP: invalid RANDOM len\n");
1873 return (-1);
1874 }
1875 got_random = 1;
1876 } else if (ptype == SCTP_HMAC_LIST) {
1877 struct sctp_auth_hmac_algo *hmacs;
1878 uint8_t store[SCTP_PARAM_BUFFER_SIZE];
1879 int num_hmacs;
1880
1881 if (plen > sizeof(store)) {
1882 break;
1883 }
1884 phdr = sctp_get_next_param(m, offset,
1885 (struct sctp_paramhdr *)store,
1886 plen);
1887 if (phdr == NULL) {
1888 return (-1);
1889 }
1890 hmacs = (struct sctp_auth_hmac_algo *)phdr;
1891 num_hmacs = (plen - sizeof(*hmacs)) / sizeof(hmacs->hmac_ids[0]);
1892 /* validate the hmac list */
1893 if (sctp_verify_hmac_param(hmacs, num_hmacs)) {
1894 SCTPDBG(SCTP_DEBUG_AUTH1,
1895 "SCTP: invalid HMAC param\n");
1896 return (-1);
1897 }
1898 got_hmacs = 1;
1899 } else if (ptype == SCTP_CHUNK_LIST) {
1900 struct sctp_auth_chunk_list *chunks;
1901 uint8_t chunks_store[SCTP_SMALL_CHUNK_STORE];
1902 int i, num_chunks;
1903
1904 if (plen > sizeof(chunks_store)) {
1905 break;
1906 }
1907 phdr = sctp_get_next_param(m, offset,
1908 (struct sctp_paramhdr *)chunks_store,
1909 plen);
1910 if (phdr == NULL) {
1911 return (-1);
1912 }
1913 /*-
1914 * Flip through the list and mark that the
1915 * peer supports asconf/asconf_ack.
1916 */
1917 chunks = (struct sctp_auth_chunk_list *)phdr;
1918 num_chunks = plen - sizeof(*chunks);
1919 for (i = 0; i < num_chunks; i++) {
1920 /* record asconf/asconf-ack if listed */
1921 if (chunks->chunk_types[i] == SCTP_ASCONF)
1922 saw_asconf = 1;
1923 if (chunks->chunk_types[i] == SCTP_ASCONF_ACK)
1924 saw_asconf_ack = 1;
1925
1926 }
1927 if (num_chunks)
1928 got_chklist = 1;
1929 }
1930 offset += SCTP_SIZE32(plen);
1931 if (offset >= limit) {
1932 break;
1933 }
1934 phdr = sctp_get_next_param(m, offset, ¶m_buf,
1935 sizeof(param_buf));
1936 }
1937 /* validate authentication required parameters */
1938 if (got_random && got_hmacs) {
1939 peer_supports_auth = 1;
1940 } else {
1941 peer_supports_auth = 0;
1942 }
1943 if (!peer_supports_auth && got_chklist) {
1944 SCTPDBG(SCTP_DEBUG_AUTH1,
1945 "SCTP: peer sent chunk list w/o AUTH\n");
1946 return (-1);
1947 }
1948 if (peer_supports_asconf && !peer_supports_auth) {
1949 SCTPDBG(SCTP_DEBUG_AUTH1,
1950 "SCTP: peer supports ASCONF but not AUTH\n");
1951 return (-1);
1952 } else if ((peer_supports_asconf) && (peer_supports_auth) &&
1953 ((saw_asconf == 0) || (saw_asconf_ack == 0))) {
1954 return (-2);
1955 }
1956 return (0);
1957 }
1958
1959 void
1960 sctp_initialize_auth_params(struct sctp_inpcb *inp, struct sctp_tcb *stcb)
1961 {
1962 uint16_t chunks_len = 0;
1963 uint16_t hmacs_len = 0;
1964 uint16_t random_len = SCTP_AUTH_RANDOM_SIZE_DEFAULT;
1965 sctp_key_t *new_key;
1966 uint16_t keylen;
1967
1968 /* initialize hmac list from endpoint */
1969 stcb->asoc.local_hmacs = sctp_copy_hmaclist(inp->sctp_ep.local_hmacs);
1970 if (stcb->asoc.local_hmacs != NULL) {
1971 hmacs_len = stcb->asoc.local_hmacs->num_algo *
1972 sizeof(stcb->asoc.local_hmacs->hmac[0]);
1973 }
1974 /* initialize auth chunks list from endpoint */
1975 stcb->asoc.local_auth_chunks =
1976 sctp_copy_chunklist(inp->sctp_ep.local_auth_chunks);
1977 if (stcb->asoc.local_auth_chunks != NULL) {
1978 int i;
1979
1980 for (i = 0; i < 256; i++) {
1981 if (stcb->asoc.local_auth_chunks->chunks[i])
1982 chunks_len++;
1983 }
1984 }
1985 /* copy defaults from the endpoint */
1986 stcb->asoc.authinfo.active_keyid = inp->sctp_ep.default_keyid;
1987
1988 /* copy out the shared key list (by reference) from the endpoint */
1989 (void)sctp_copy_skeylist(&inp->sctp_ep.shared_keys,
1990 &stcb->asoc.shared_keys);
1991
1992 /* now set the concatenated key (random + chunks + hmacs) */
1993 /* key includes parameter headers */
1994 keylen = (3 * sizeof(struct sctp_paramhdr)) + random_len + chunks_len +
1995 hmacs_len;
1996 new_key = sctp_alloc_key(keylen);
1997 if (new_key != NULL) {
1998 struct sctp_paramhdr *ph;
1999 int plen;
2000
2001 /* generate and copy in the RANDOM */
2002 ph = (struct sctp_paramhdr *)new_key->key;
2003 ph->param_type = htons(SCTP_RANDOM);
2004 plen = sizeof(*ph) + random_len;
2005 ph->param_length = htons(plen);
2006 SCTP_READ_RANDOM(new_key->key + sizeof(*ph), random_len);
2007 keylen = plen;
2008
2009 /* append in the AUTH chunks */
2010 /* NOTE: currently we always have chunks to list */
2011 ph = (struct sctp_paramhdr *)(new_key->key + keylen);
2012 ph->param_type = htons(SCTP_CHUNK_LIST);
2013 plen = sizeof(*ph) + chunks_len;
2014 ph->param_length = htons(plen);
2015 keylen += sizeof(*ph);
2016 if (stcb->asoc.local_auth_chunks) {
2017 int i;
2018
2019 for (i = 0; i < 256; i++) {
2020 if (stcb->asoc.local_auth_chunks->chunks[i])
2021 new_key->key[keylen++] = i;
2022 }
2023 }
2024 /* append in the HMACs */
2025 ph = (struct sctp_paramhdr *)(new_key->key + keylen);
2026 ph->param_type = htons(SCTP_HMAC_LIST);
2027 plen = sizeof(*ph) + hmacs_len;
2028 ph->param_length = htons(plen);
2029 keylen += sizeof(*ph);
2030 (void)sctp_serialize_hmaclist(stcb->asoc.local_hmacs,
2031 new_key->key + keylen);
2032 }
2033 if (stcb->asoc.authinfo.random != NULL)
2034 sctp_free_key(stcb->asoc.authinfo.random);
2035 stcb->asoc.authinfo.random = new_key;
2036 stcb->asoc.authinfo.random_len = random_len;
2037 }
Cache object: 4a9e15159081f6ee713856f9fb841dbf
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