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/10.0/sys/netinet/sctp_auth.c 268434 2014-07-08 21:55:27Z delphij $");
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 bzero(chklist, 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 bcopy(list, new_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 /* is chunk restricted? */
137 if ((chunk == SCTP_ASCONF) ||
138 (chunk == SCTP_ASCONF_ACK)) {
139 return (-1);
140 }
141 if (list->chunks[chunk] == 1) {
142 list->chunks[chunk] = 0;
143 list->num_chunks--;
144 SCTPDBG(SCTP_DEBUG_AUTH1,
145 "SCTP: deleted chunk %u (0x%02x) from Auth list\n",
146 chunk, chunk);
147 }
148 return (0);
149 }
150
151 size_t
152 sctp_auth_get_chklist_size(const sctp_auth_chklist_t * list)
153 {
154 if (list == NULL)
155 return (0);
156 else
157 return (list->num_chunks);
158 }
159
160 /*
161 * set the default list of chunks requiring AUTH
162 */
163 void
164 sctp_auth_set_default_chunks(sctp_auth_chklist_t * list)
165 {
166 (void)sctp_auth_add_chunk(SCTP_ASCONF, list);
167 (void)sctp_auth_add_chunk(SCTP_ASCONF_ACK, list);
168 }
169
170 /*
171 * return the current number and list of required chunks caller must
172 * guarantee ptr has space for up to 256 bytes
173 */
174 int
175 sctp_serialize_auth_chunks(const sctp_auth_chklist_t * list, uint8_t * ptr)
176 {
177 int i, count = 0;
178
179 if (list == NULL)
180 return (0);
181
182 for (i = 0; i < 256; i++) {
183 if (list->chunks[i] != 0) {
184 *ptr++ = i;
185 count++;
186 }
187 }
188 return (count);
189 }
190
191 int
192 sctp_pack_auth_chunks(const sctp_auth_chklist_t * list, uint8_t * ptr)
193 {
194 int i, size = 0;
195
196 if (list == NULL)
197 return (0);
198
199 if (list->num_chunks <= 32) {
200 /* just list them, one byte each */
201 for (i = 0; i < 256; i++) {
202 if (list->chunks[i] != 0) {
203 *ptr++ = i;
204 size++;
205 }
206 }
207 } else {
208 int index, offset;
209
210 /* pack into a 32 byte bitfield */
211 for (i = 0; i < 256; i++) {
212 if (list->chunks[i] != 0) {
213 index = i / 8;
214 offset = i % 8;
215 ptr[index] |= (1 << offset);
216 }
217 }
218 size = 32;
219 }
220 return (size);
221 }
222
223 int
224 sctp_unpack_auth_chunks(const uint8_t * ptr, uint8_t num_chunks,
225 sctp_auth_chklist_t * list)
226 {
227 int i;
228 int size;
229
230 if (list == NULL)
231 return (0);
232
233 if (num_chunks <= 32) {
234 /* just pull them, one byte each */
235 for (i = 0; i < num_chunks; i++) {
236 (void)sctp_auth_add_chunk(*ptr++, list);
237 }
238 size = num_chunks;
239 } else {
240 int index, offset;
241
242 /* unpack from a 32 byte bitfield */
243 for (index = 0; index < 32; index++) {
244 for (offset = 0; offset < 8; offset++) {
245 if (ptr[index] & (1 << offset)) {
246 (void)sctp_auth_add_chunk((index * 8) + offset, list);
247 }
248 }
249 }
250 size = 32;
251 }
252 return (size);
253 }
254
255
256 /*
257 * allocate structure space for a key of length keylen
258 */
259 sctp_key_t *
260 sctp_alloc_key(uint32_t keylen)
261 {
262 sctp_key_t *new_key;
263
264 SCTP_MALLOC(new_key, sctp_key_t *, sizeof(*new_key) + keylen,
265 SCTP_M_AUTH_KY);
266 if (new_key == NULL) {
267 /* out of memory */
268 return (NULL);
269 }
270 new_key->keylen = keylen;
271 return (new_key);
272 }
273
274 void
275 sctp_free_key(sctp_key_t * key)
276 {
277 if (key != NULL)
278 SCTP_FREE(key, SCTP_M_AUTH_KY);
279 }
280
281 void
282 sctp_print_key(sctp_key_t * key, const char *str)
283 {
284 uint32_t i;
285
286 if (key == NULL) {
287 SCTP_PRINTF("%s: [Null key]\n", str);
288 return;
289 }
290 SCTP_PRINTF("%s: len %u, ", str, key->keylen);
291 if (key->keylen) {
292 for (i = 0; i < key->keylen; i++)
293 SCTP_PRINTF("%02x", key->key[i]);
294 SCTP_PRINTF("\n");
295 } else {
296 SCTP_PRINTF("[Null key]\n");
297 }
298 }
299
300 void
301 sctp_show_key(sctp_key_t * key, const char *str)
302 {
303 uint32_t i;
304
305 if (key == NULL) {
306 SCTP_PRINTF("%s: [Null key]\n", str);
307 return;
308 }
309 SCTP_PRINTF("%s: len %u, ", str, key->keylen);
310 if (key->keylen) {
311 for (i = 0; i < key->keylen; i++)
312 SCTP_PRINTF("%02x", key->key[i]);
313 SCTP_PRINTF("\n");
314 } else {
315 SCTP_PRINTF("[Null key]\n");
316 }
317 }
318
319 static uint32_t
320 sctp_get_keylen(sctp_key_t * key)
321 {
322 if (key != NULL)
323 return (key->keylen);
324 else
325 return (0);
326 }
327
328 /*
329 * generate a new random key of length 'keylen'
330 */
331 sctp_key_t *
332 sctp_generate_random_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 SCTP_READ_RANDOM(new_key->key, keylen);
342 new_key->keylen = keylen;
343 return (new_key);
344 }
345
346 sctp_key_t *
347 sctp_set_key(uint8_t * key, uint32_t keylen)
348 {
349 sctp_key_t *new_key;
350
351 new_key = sctp_alloc_key(keylen);
352 if (new_key == NULL) {
353 /* out of memory */
354 return (NULL);
355 }
356 bcopy(key, new_key->key, keylen);
357 return (new_key);
358 }
359
360 /*-
361 * given two keys of variable size, compute which key is "larger/smaller"
362 * returns: 1 if key1 > key2
363 * -1 if key1 < key2
364 * 0 if key1 = key2
365 */
366 static int
367 sctp_compare_key(sctp_key_t * key1, sctp_key_t * key2)
368 {
369 uint32_t maxlen;
370 uint32_t i;
371 uint32_t key1len, key2len;
372 uint8_t *key_1, *key_2;
373 uint8_t val1, val2;
374
375 /* sanity/length check */
376 key1len = sctp_get_keylen(key1);
377 key2len = sctp_get_keylen(key2);
378 if ((key1len == 0) && (key2len == 0))
379 return (0);
380 else if (key1len == 0)
381 return (-1);
382 else if (key2len == 0)
383 return (1);
384
385 if (key1len < key2len) {
386 maxlen = key2len;
387 } else {
388 maxlen = key1len;
389 }
390 key_1 = key1->key;
391 key_2 = key2->key;
392 /* check for numeric equality */
393 for (i = 0; i < maxlen; i++) {
394 /* left-pad with zeros */
395 val1 = (i < (maxlen - key1len)) ? 0 : *(key_1++);
396 val2 = (i < (maxlen - key2len)) ? 0 : *(key_2++);
397 if (val1 > val2) {
398 return (1);
399 } else if (val1 < val2) {
400 return (-1);
401 }
402 }
403 /* keys are equal value, so check lengths */
404 if (key1len == key2len)
405 return (0);
406 else if (key1len < key2len)
407 return (-1);
408 else
409 return (1);
410 }
411
412 /*
413 * generate the concatenated keying material based on the two keys and the
414 * shared key (if available). draft-ietf-tsvwg-auth specifies the specific
415 * order for concatenation
416 */
417 sctp_key_t *
418 sctp_compute_hashkey(sctp_key_t * key1, sctp_key_t * key2, sctp_key_t * shared)
419 {
420 uint32_t keylen;
421 sctp_key_t *new_key;
422 uint8_t *key_ptr;
423
424 keylen = sctp_get_keylen(key1) + sctp_get_keylen(key2) +
425 sctp_get_keylen(shared);
426
427 if (keylen > 0) {
428 /* get space for the new key */
429 new_key = sctp_alloc_key(keylen);
430 if (new_key == NULL) {
431 /* out of memory */
432 return (NULL);
433 }
434 new_key->keylen = keylen;
435 key_ptr = new_key->key;
436 } else {
437 /* all keys empty/null?! */
438 return (NULL);
439 }
440
441 /* concatenate the keys */
442 if (sctp_compare_key(key1, key2) <= 0) {
443 /* key is shared + key1 + key2 */
444 if (sctp_get_keylen(shared)) {
445 bcopy(shared->key, key_ptr, shared->keylen);
446 key_ptr += shared->keylen;
447 }
448 if (sctp_get_keylen(key1)) {
449 bcopy(key1->key, key_ptr, key1->keylen);
450 key_ptr += key1->keylen;
451 }
452 if (sctp_get_keylen(key2)) {
453 bcopy(key2->key, key_ptr, key2->keylen);
454 }
455 } else {
456 /* key is shared + key2 + key1 */
457 if (sctp_get_keylen(shared)) {
458 bcopy(shared->key, key_ptr, shared->keylen);
459 key_ptr += shared->keylen;
460 }
461 if (sctp_get_keylen(key2)) {
462 bcopy(key2->key, key_ptr, key2->keylen);
463 key_ptr += key2->keylen;
464 }
465 if (sctp_get_keylen(key1)) {
466 bcopy(key1->key, key_ptr, key1->keylen);
467 }
468 }
469 return (new_key);
470 }
471
472
473 sctp_sharedkey_t *
474 sctp_alloc_sharedkey(void)
475 {
476 sctp_sharedkey_t *new_key;
477
478 SCTP_MALLOC(new_key, sctp_sharedkey_t *, sizeof(*new_key),
479 SCTP_M_AUTH_KY);
480 if (new_key == NULL) {
481 /* out of memory */
482 return (NULL);
483 }
484 new_key->keyid = 0;
485 new_key->key = NULL;
486 new_key->refcount = 1;
487 new_key->deactivated = 0;
488 return (new_key);
489 }
490
491 void
492 sctp_free_sharedkey(sctp_sharedkey_t * skey)
493 {
494 if (skey == NULL)
495 return;
496
497 if (SCTP_DECREMENT_AND_CHECK_REFCOUNT(&skey->refcount)) {
498 if (skey->key != NULL)
499 sctp_free_key(skey->key);
500 SCTP_FREE(skey, SCTP_M_AUTH_KY);
501 }
502 }
503
504 sctp_sharedkey_t *
505 sctp_find_sharedkey(struct sctp_keyhead *shared_keys, uint16_t key_id)
506 {
507 sctp_sharedkey_t *skey;
508
509 LIST_FOREACH(skey, shared_keys, next) {
510 if (skey->keyid == key_id)
511 return (skey);
512 }
513 return (NULL);
514 }
515
516 int
517 sctp_insert_sharedkey(struct sctp_keyhead *shared_keys,
518 sctp_sharedkey_t * new_skey)
519 {
520 sctp_sharedkey_t *skey;
521
522 if ((shared_keys == NULL) || (new_skey == NULL))
523 return (EINVAL);
524
525 /* insert into an empty list? */
526 if (LIST_EMPTY(shared_keys)) {
527 LIST_INSERT_HEAD(shared_keys, new_skey, next);
528 return (0);
529 }
530 /* insert into the existing list, ordered by key id */
531 LIST_FOREACH(skey, shared_keys, next) {
532 if (new_skey->keyid < skey->keyid) {
533 /* insert it before here */
534 LIST_INSERT_BEFORE(skey, new_skey, next);
535 return (0);
536 } else if (new_skey->keyid == skey->keyid) {
537 /* replace the existing key */
538 /* verify this key *can* be replaced */
539 if ((skey->deactivated) && (skey->refcount > 1)) {
540 SCTPDBG(SCTP_DEBUG_AUTH1,
541 "can't replace shared key id %u\n",
542 new_skey->keyid);
543 return (EBUSY);
544 }
545 SCTPDBG(SCTP_DEBUG_AUTH1,
546 "replacing shared key id %u\n",
547 new_skey->keyid);
548 LIST_INSERT_BEFORE(skey, new_skey, next);
549 LIST_REMOVE(skey, next);
550 sctp_free_sharedkey(skey);
551 return (0);
552 }
553 if (LIST_NEXT(skey, next) == NULL) {
554 /* belongs at the end of the list */
555 LIST_INSERT_AFTER(skey, new_skey, next);
556 return (0);
557 }
558 }
559 /* shouldn't reach here */
560 return (0);
561 }
562
563 void
564 sctp_auth_key_acquire(struct sctp_tcb *stcb, uint16_t key_id)
565 {
566 sctp_sharedkey_t *skey;
567
568 /* find the shared key */
569 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, key_id);
570
571 /* bump the ref count */
572 if (skey) {
573 atomic_add_int(&skey->refcount, 1);
574 SCTPDBG(SCTP_DEBUG_AUTH2,
575 "%s: stcb %p key %u refcount acquire to %d\n",
576 __FUNCTION__, (void *)stcb, key_id, skey->refcount);
577 }
578 }
579
580 void
581 sctp_auth_key_release(struct sctp_tcb *stcb, uint16_t key_id, int so_locked
582 #if !defined(__APPLE__) && !defined(SCTP_SO_LOCK_TESTING)
583 SCTP_UNUSED
584 #endif
585 )
586 {
587 sctp_sharedkey_t *skey;
588
589 /* find the shared key */
590 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, key_id);
591
592 /* decrement the ref count */
593 if (skey) {
594 sctp_free_sharedkey(skey);
595 SCTPDBG(SCTP_DEBUG_AUTH2,
596 "%s: stcb %p key %u refcount release to %d\n",
597 __FUNCTION__, (void *)stcb, key_id, skey->refcount);
598
599 /* see if a notification should be generated */
600 if ((skey->refcount <= 1) && (skey->deactivated)) {
601 /* notify ULP that key is no longer used */
602 sctp_ulp_notify(SCTP_NOTIFY_AUTH_FREE_KEY, stcb,
603 key_id, 0, so_locked);
604 SCTPDBG(SCTP_DEBUG_AUTH2,
605 "%s: stcb %p key %u no longer used, %d\n",
606 __FUNCTION__, (void *)stcb, key_id, skey->refcount);
607 }
608 }
609 }
610
611 static sctp_sharedkey_t *
612 sctp_copy_sharedkey(const sctp_sharedkey_t * skey)
613 {
614 sctp_sharedkey_t *new_skey;
615
616 if (skey == NULL)
617 return (NULL);
618 new_skey = sctp_alloc_sharedkey();
619 if (new_skey == NULL)
620 return (NULL);
621 if (skey->key != NULL)
622 new_skey->key = sctp_set_key(skey->key->key, skey->key->keylen);
623 else
624 new_skey->key = NULL;
625 new_skey->keyid = skey->keyid;
626 return (new_skey);
627 }
628
629 int
630 sctp_copy_skeylist(const struct sctp_keyhead *src, struct sctp_keyhead *dest)
631 {
632 sctp_sharedkey_t *skey, *new_skey;
633 int count = 0;
634
635 if ((src == NULL) || (dest == NULL))
636 return (0);
637 LIST_FOREACH(skey, src, next) {
638 new_skey = sctp_copy_sharedkey(skey);
639 if (new_skey != NULL) {
640 (void)sctp_insert_sharedkey(dest, new_skey);
641 count++;
642 }
643 }
644 return (count);
645 }
646
647
648 sctp_hmaclist_t *
649 sctp_alloc_hmaclist(uint8_t num_hmacs)
650 {
651 sctp_hmaclist_t *new_list;
652 int alloc_size;
653
654 alloc_size = sizeof(*new_list) + num_hmacs * sizeof(new_list->hmac[0]);
655 SCTP_MALLOC(new_list, sctp_hmaclist_t *, alloc_size,
656 SCTP_M_AUTH_HL);
657 if (new_list == NULL) {
658 /* out of memory */
659 return (NULL);
660 }
661 new_list->max_algo = num_hmacs;
662 new_list->num_algo = 0;
663 return (new_list);
664 }
665
666 void
667 sctp_free_hmaclist(sctp_hmaclist_t * list)
668 {
669 if (list != NULL) {
670 SCTP_FREE(list, SCTP_M_AUTH_HL);
671 list = NULL;
672 }
673 }
674
675 int
676 sctp_auth_add_hmacid(sctp_hmaclist_t * list, uint16_t hmac_id)
677 {
678 int i;
679
680 if (list == NULL)
681 return (-1);
682 if (list->num_algo == list->max_algo) {
683 SCTPDBG(SCTP_DEBUG_AUTH1,
684 "SCTP: HMAC id list full, ignoring add %u\n", hmac_id);
685 return (-1);
686 }
687 if ((hmac_id != SCTP_AUTH_HMAC_ID_SHA1) &&
688 (hmac_id != SCTP_AUTH_HMAC_ID_SHA256)) {
689 return (-1);
690 }
691 /* Now is it already in the list */
692 for (i = 0; i < list->num_algo; i++) {
693 if (list->hmac[i] == hmac_id) {
694 /* already in list */
695 return (-1);
696 }
697 }
698 SCTPDBG(SCTP_DEBUG_AUTH1, "SCTP: add HMAC id %u to list\n", hmac_id);
699 list->hmac[list->num_algo++] = hmac_id;
700 return (0);
701 }
702
703 sctp_hmaclist_t *
704 sctp_copy_hmaclist(sctp_hmaclist_t * list)
705 {
706 sctp_hmaclist_t *new_list;
707 int i;
708
709 if (list == NULL)
710 return (NULL);
711 /* get a new list */
712 new_list = sctp_alloc_hmaclist(list->max_algo);
713 if (new_list == NULL)
714 return (NULL);
715 /* copy it */
716 new_list->max_algo = list->max_algo;
717 new_list->num_algo = list->num_algo;
718 for (i = 0; i < list->num_algo; i++)
719 new_list->hmac[i] = list->hmac[i];
720 return (new_list);
721 }
722
723 sctp_hmaclist_t *
724 sctp_default_supported_hmaclist(void)
725 {
726 sctp_hmaclist_t *new_list;
727
728 new_list = sctp_alloc_hmaclist(2);
729 if (new_list == NULL)
730 return (NULL);
731 /* We prefer SHA256, so list it first */
732 (void)sctp_auth_add_hmacid(new_list, SCTP_AUTH_HMAC_ID_SHA256);
733 (void)sctp_auth_add_hmacid(new_list, SCTP_AUTH_HMAC_ID_SHA1);
734 return (new_list);
735 }
736
737 /*-
738 * HMAC algos are listed in priority/preference order
739 * find the best HMAC id to use for the peer based on local support
740 */
741 uint16_t
742 sctp_negotiate_hmacid(sctp_hmaclist_t * peer, sctp_hmaclist_t * local)
743 {
744 int i, j;
745
746 if ((local == NULL) || (peer == NULL))
747 return (SCTP_AUTH_HMAC_ID_RSVD);
748
749 for (i = 0; i < peer->num_algo; i++) {
750 for (j = 0; j < local->num_algo; j++) {
751 if (peer->hmac[i] == local->hmac[j]) {
752 /* found the "best" one */
753 SCTPDBG(SCTP_DEBUG_AUTH1,
754 "SCTP: negotiated peer HMAC id %u\n",
755 peer->hmac[i]);
756 return (peer->hmac[i]);
757 }
758 }
759 }
760 /* didn't find one! */
761 return (SCTP_AUTH_HMAC_ID_RSVD);
762 }
763
764 /*-
765 * serialize the HMAC algo list and return space used
766 * caller must guarantee ptr has appropriate space
767 */
768 int
769 sctp_serialize_hmaclist(sctp_hmaclist_t * list, uint8_t * ptr)
770 {
771 int i;
772 uint16_t hmac_id;
773
774 if (list == NULL)
775 return (0);
776
777 for (i = 0; i < list->num_algo; i++) {
778 hmac_id = htons(list->hmac[i]);
779 bcopy(&hmac_id, ptr, sizeof(hmac_id));
780 ptr += sizeof(hmac_id);
781 }
782 return (list->num_algo * sizeof(hmac_id));
783 }
784
785 int
786 sctp_verify_hmac_param(struct sctp_auth_hmac_algo *hmacs, uint32_t num_hmacs)
787 {
788 uint32_t i;
789
790 for (i = 0; i < num_hmacs; i++) {
791 if (ntohs(hmacs->hmac_ids[i]) == SCTP_AUTH_HMAC_ID_SHA1) {
792 return (0);
793 }
794 }
795 return (-1);
796 }
797
798 sctp_authinfo_t *
799 sctp_alloc_authinfo(void)
800 {
801 sctp_authinfo_t *new_authinfo;
802
803 SCTP_MALLOC(new_authinfo, sctp_authinfo_t *, sizeof(*new_authinfo),
804 SCTP_M_AUTH_IF);
805
806 if (new_authinfo == NULL) {
807 /* out of memory */
808 return (NULL);
809 }
810 bzero(new_authinfo, sizeof(*new_authinfo));
811 return (new_authinfo);
812 }
813
814 void
815 sctp_free_authinfo(sctp_authinfo_t * authinfo)
816 {
817 if (authinfo == NULL)
818 return;
819
820 if (authinfo->random != NULL)
821 sctp_free_key(authinfo->random);
822 if (authinfo->peer_random != NULL)
823 sctp_free_key(authinfo->peer_random);
824 if (authinfo->assoc_key != NULL)
825 sctp_free_key(authinfo->assoc_key);
826 if (authinfo->recv_key != NULL)
827 sctp_free_key(authinfo->recv_key);
828
829 /* We are NOT dynamically allocating authinfo's right now... */
830 /* SCTP_FREE(authinfo, SCTP_M_AUTH_??); */
831 }
832
833
834 uint32_t
835 sctp_get_auth_chunk_len(uint16_t hmac_algo)
836 {
837 int size;
838
839 size = sizeof(struct sctp_auth_chunk) + sctp_get_hmac_digest_len(hmac_algo);
840 return (SCTP_SIZE32(size));
841 }
842
843 uint32_t
844 sctp_get_hmac_digest_len(uint16_t hmac_algo)
845 {
846 switch (hmac_algo) {
847 case SCTP_AUTH_HMAC_ID_SHA1:
848 return (SCTP_AUTH_DIGEST_LEN_SHA1);
849 case SCTP_AUTH_HMAC_ID_SHA256:
850 return (SCTP_AUTH_DIGEST_LEN_SHA256);
851 default:
852 /* unknown HMAC algorithm: can't do anything */
853 return (0);
854 } /* end switch */
855 }
856
857 static inline int
858 sctp_get_hmac_block_len(uint16_t hmac_algo)
859 {
860 switch (hmac_algo) {
861 case SCTP_AUTH_HMAC_ID_SHA1:
862 return (64);
863 case SCTP_AUTH_HMAC_ID_SHA256:
864 return (64);
865 case SCTP_AUTH_HMAC_ID_RSVD:
866 default:
867 /* unknown HMAC algorithm: can't do anything */
868 return (0);
869 } /* end switch */
870 }
871
872 static void
873 sctp_hmac_init(uint16_t hmac_algo, sctp_hash_context_t * ctx)
874 {
875 switch (hmac_algo) {
876 case SCTP_AUTH_HMAC_ID_SHA1:
877 SCTP_SHA1_INIT(&ctx->sha1);
878 break;
879 case SCTP_AUTH_HMAC_ID_SHA256:
880 SCTP_SHA256_INIT(&ctx->sha256);
881 break;
882 case SCTP_AUTH_HMAC_ID_RSVD:
883 default:
884 /* unknown HMAC algorithm: can't do anything */
885 return;
886 } /* end switch */
887 }
888
889 static void
890 sctp_hmac_update(uint16_t hmac_algo, sctp_hash_context_t * ctx,
891 uint8_t * text, uint32_t textlen)
892 {
893 switch (hmac_algo) {
894 case SCTP_AUTH_HMAC_ID_SHA1:
895 SCTP_SHA1_UPDATE(&ctx->sha1, text, textlen);
896 break;
897 case SCTP_AUTH_HMAC_ID_SHA256:
898 SCTP_SHA256_UPDATE(&ctx->sha256, text, textlen);
899 break;
900 case SCTP_AUTH_HMAC_ID_RSVD:
901 default:
902 /* unknown HMAC algorithm: can't do anything */
903 return;
904 } /* end switch */
905 }
906
907 static void
908 sctp_hmac_final(uint16_t hmac_algo, sctp_hash_context_t * ctx,
909 uint8_t * digest)
910 {
911 switch (hmac_algo) {
912 case SCTP_AUTH_HMAC_ID_SHA1:
913 SCTP_SHA1_FINAL(digest, &ctx->sha1);
914 break;
915 case SCTP_AUTH_HMAC_ID_SHA256:
916 SCTP_SHA256_FINAL(digest, &ctx->sha256);
917 break;
918 case SCTP_AUTH_HMAC_ID_RSVD:
919 default:
920 /* unknown HMAC algorithm: can't do anything */
921 return;
922 } /* end switch */
923 }
924
925 /*-
926 * Keyed-Hashing for Message Authentication: FIPS 198 (RFC 2104)
927 *
928 * Compute the HMAC digest using the desired hash key, text, and HMAC
929 * algorithm. Resulting digest is placed in 'digest' and digest length
930 * is returned, if the HMAC was performed.
931 *
932 * WARNING: it is up to the caller to supply sufficient space to hold the
933 * resultant digest.
934 */
935 uint32_t
936 sctp_hmac(uint16_t hmac_algo, uint8_t * key, uint32_t keylen,
937 uint8_t * text, uint32_t textlen, uint8_t * digest)
938 {
939 uint32_t digestlen;
940 uint32_t blocklen;
941 sctp_hash_context_t ctx;
942 uint8_t ipad[128], opad[128]; /* keyed hash inner/outer pads */
943 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
944 uint32_t i;
945
946 /* sanity check the material and length */
947 if ((key == NULL) || (keylen == 0) || (text == NULL) ||
948 (textlen == 0) || (digest == NULL)) {
949 /* can't do HMAC with empty key or text or digest store */
950 return (0);
951 }
952 /* validate the hmac algo and get the digest length */
953 digestlen = sctp_get_hmac_digest_len(hmac_algo);
954 if (digestlen == 0)
955 return (0);
956
957 /* hash the key if it is longer than the hash block size */
958 blocklen = sctp_get_hmac_block_len(hmac_algo);
959 if (keylen > blocklen) {
960 sctp_hmac_init(hmac_algo, &ctx);
961 sctp_hmac_update(hmac_algo, &ctx, key, keylen);
962 sctp_hmac_final(hmac_algo, &ctx, temp);
963 /* set the hashed key as the key */
964 keylen = digestlen;
965 key = temp;
966 }
967 /* initialize the inner/outer pads with the key and "append" zeroes */
968 bzero(ipad, blocklen);
969 bzero(opad, blocklen);
970 bcopy(key, ipad, keylen);
971 bcopy(key, opad, keylen);
972
973 /* XOR the key with ipad and opad values */
974 for (i = 0; i < blocklen; i++) {
975 ipad[i] ^= 0x36;
976 opad[i] ^= 0x5c;
977 }
978
979 /* perform inner hash */
980 sctp_hmac_init(hmac_algo, &ctx);
981 sctp_hmac_update(hmac_algo, &ctx, ipad, blocklen);
982 sctp_hmac_update(hmac_algo, &ctx, text, textlen);
983 sctp_hmac_final(hmac_algo, &ctx, temp);
984
985 /* perform outer hash */
986 sctp_hmac_init(hmac_algo, &ctx);
987 sctp_hmac_update(hmac_algo, &ctx, opad, blocklen);
988 sctp_hmac_update(hmac_algo, &ctx, temp, digestlen);
989 sctp_hmac_final(hmac_algo, &ctx, digest);
990
991 return (digestlen);
992 }
993
994 /* mbuf version */
995 uint32_t
996 sctp_hmac_m(uint16_t hmac_algo, uint8_t * key, uint32_t keylen,
997 struct mbuf *m, uint32_t m_offset, uint8_t * digest, uint32_t trailer)
998 {
999 uint32_t digestlen;
1000 uint32_t blocklen;
1001 sctp_hash_context_t ctx;
1002 uint8_t ipad[128], opad[128]; /* keyed hash inner/outer pads */
1003 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
1004 uint32_t i;
1005 struct mbuf *m_tmp;
1006
1007 /* sanity check the material and length */
1008 if ((key == NULL) || (keylen == 0) || (m == NULL) || (digest == NULL)) {
1009 /* can't do HMAC with empty key or text or digest store */
1010 return (0);
1011 }
1012 /* validate the hmac algo and get the digest length */
1013 digestlen = sctp_get_hmac_digest_len(hmac_algo);
1014 if (digestlen == 0)
1015 return (0);
1016
1017 /* hash the key if it is longer than the hash block size */
1018 blocklen = sctp_get_hmac_block_len(hmac_algo);
1019 if (keylen > blocklen) {
1020 sctp_hmac_init(hmac_algo, &ctx);
1021 sctp_hmac_update(hmac_algo, &ctx, key, keylen);
1022 sctp_hmac_final(hmac_algo, &ctx, temp);
1023 /* set the hashed key as the key */
1024 keylen = digestlen;
1025 key = temp;
1026 }
1027 /* initialize the inner/outer pads with the key and "append" zeroes */
1028 bzero(ipad, blocklen);
1029 bzero(opad, blocklen);
1030 bcopy(key, ipad, keylen);
1031 bcopy(key, opad, keylen);
1032
1033 /* XOR the key with ipad and opad values */
1034 for (i = 0; i < blocklen; i++) {
1035 ipad[i] ^= 0x36;
1036 opad[i] ^= 0x5c;
1037 }
1038
1039 /* perform inner hash */
1040 sctp_hmac_init(hmac_algo, &ctx);
1041 sctp_hmac_update(hmac_algo, &ctx, ipad, blocklen);
1042 /* find the correct starting mbuf and offset (get start of text) */
1043 m_tmp = m;
1044 while ((m_tmp != NULL) && (m_offset >= (uint32_t) SCTP_BUF_LEN(m_tmp))) {
1045 m_offset -= SCTP_BUF_LEN(m_tmp);
1046 m_tmp = SCTP_BUF_NEXT(m_tmp);
1047 }
1048 /* now use the rest of the mbuf chain for the text */
1049 while (m_tmp != NULL) {
1050 if ((SCTP_BUF_NEXT(m_tmp) == NULL) && trailer) {
1051 sctp_hmac_update(hmac_algo, &ctx, mtod(m_tmp, uint8_t *) + m_offset,
1052 SCTP_BUF_LEN(m_tmp) - (trailer + m_offset));
1053 } else {
1054 sctp_hmac_update(hmac_algo, &ctx, mtod(m_tmp, uint8_t *) + m_offset,
1055 SCTP_BUF_LEN(m_tmp) - m_offset);
1056 }
1057
1058 /* clear the offset since it's only for the first mbuf */
1059 m_offset = 0;
1060 m_tmp = SCTP_BUF_NEXT(m_tmp);
1061 }
1062 sctp_hmac_final(hmac_algo, &ctx, temp);
1063
1064 /* perform outer hash */
1065 sctp_hmac_init(hmac_algo, &ctx);
1066 sctp_hmac_update(hmac_algo, &ctx, opad, blocklen);
1067 sctp_hmac_update(hmac_algo, &ctx, temp, digestlen);
1068 sctp_hmac_final(hmac_algo, &ctx, digest);
1069
1070 return (digestlen);
1071 }
1072
1073 /*-
1074 * verify the HMAC digest using the desired hash key, text, and HMAC
1075 * algorithm.
1076 * Returns -1 on error, 0 on success.
1077 */
1078 int
1079 sctp_verify_hmac(uint16_t hmac_algo, uint8_t * key, uint32_t keylen,
1080 uint8_t * text, uint32_t textlen,
1081 uint8_t * digest, uint32_t digestlen)
1082 {
1083 uint32_t len;
1084 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
1085
1086 /* sanity check the material and length */
1087 if ((key == NULL) || (keylen == 0) ||
1088 (text == NULL) || (textlen == 0) || (digest == NULL)) {
1089 /* can't do HMAC with empty key or text or digest */
1090 return (-1);
1091 }
1092 len = sctp_get_hmac_digest_len(hmac_algo);
1093 if ((len == 0) || (digestlen != len))
1094 return (-1);
1095
1096 /* compute the expected hash */
1097 if (sctp_hmac(hmac_algo, key, keylen, text, textlen, temp) != len)
1098 return (-1);
1099
1100 if (memcmp(digest, temp, digestlen) != 0)
1101 return (-1);
1102 else
1103 return (0);
1104 }
1105
1106
1107 /*
1108 * computes the requested HMAC using a key struct (which may be modified if
1109 * the keylen exceeds the HMAC block len).
1110 */
1111 uint32_t
1112 sctp_compute_hmac(uint16_t hmac_algo, sctp_key_t * key, uint8_t * text,
1113 uint32_t textlen, uint8_t * digest)
1114 {
1115 uint32_t digestlen;
1116 uint32_t blocklen;
1117 sctp_hash_context_t ctx;
1118 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
1119
1120 /* sanity check */
1121 if ((key == NULL) || (text == NULL) || (textlen == 0) ||
1122 (digest == NULL)) {
1123 /* can't do HMAC with empty key or text or digest store */
1124 return (0);
1125 }
1126 /* validate the hmac algo and get the digest length */
1127 digestlen = sctp_get_hmac_digest_len(hmac_algo);
1128 if (digestlen == 0)
1129 return (0);
1130
1131 /* hash the key if it is longer than the hash block size */
1132 blocklen = sctp_get_hmac_block_len(hmac_algo);
1133 if (key->keylen > blocklen) {
1134 sctp_hmac_init(hmac_algo, &ctx);
1135 sctp_hmac_update(hmac_algo, &ctx, key->key, key->keylen);
1136 sctp_hmac_final(hmac_algo, &ctx, temp);
1137 /* save the hashed key as the new key */
1138 key->keylen = digestlen;
1139 bcopy(temp, key->key, key->keylen);
1140 }
1141 return (sctp_hmac(hmac_algo, key->key, key->keylen, text, textlen,
1142 digest));
1143 }
1144
1145 /* mbuf version */
1146 uint32_t
1147 sctp_compute_hmac_m(uint16_t hmac_algo, sctp_key_t * key, struct mbuf *m,
1148 uint32_t m_offset, uint8_t * digest)
1149 {
1150 uint32_t digestlen;
1151 uint32_t blocklen;
1152 sctp_hash_context_t ctx;
1153 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
1154
1155 /* sanity check */
1156 if ((key == NULL) || (m == NULL) || (digest == NULL)) {
1157 /* can't do HMAC with empty key or text or digest store */
1158 return (0);
1159 }
1160 /* validate the hmac algo and get the digest length */
1161 digestlen = sctp_get_hmac_digest_len(hmac_algo);
1162 if (digestlen == 0)
1163 return (0);
1164
1165 /* hash the key if it is longer than the hash block size */
1166 blocklen = sctp_get_hmac_block_len(hmac_algo);
1167 if (key->keylen > blocklen) {
1168 sctp_hmac_init(hmac_algo, &ctx);
1169 sctp_hmac_update(hmac_algo, &ctx, key->key, key->keylen);
1170 sctp_hmac_final(hmac_algo, &ctx, temp);
1171 /* save the hashed key as the new key */
1172 key->keylen = digestlen;
1173 bcopy(temp, key->key, key->keylen);
1174 }
1175 return (sctp_hmac_m(hmac_algo, key->key, key->keylen, m, m_offset, digest, 0));
1176 }
1177
1178 int
1179 sctp_auth_is_supported_hmac(sctp_hmaclist_t * list, uint16_t id)
1180 {
1181 int i;
1182
1183 if ((list == NULL) || (id == SCTP_AUTH_HMAC_ID_RSVD))
1184 return (0);
1185
1186 for (i = 0; i < list->num_algo; i++)
1187 if (list->hmac[i] == id)
1188 return (1);
1189
1190 /* not in the list */
1191 return (0);
1192 }
1193
1194
1195 /*-
1196 * clear any cached key(s) if they match the given key id on an association.
1197 * the cached key(s) will be recomputed and re-cached at next use.
1198 * ASSUMES TCB_LOCK is already held
1199 */
1200 void
1201 sctp_clear_cachedkeys(struct sctp_tcb *stcb, uint16_t keyid)
1202 {
1203 if (stcb == NULL)
1204 return;
1205
1206 if (keyid == stcb->asoc.authinfo.assoc_keyid) {
1207 sctp_free_key(stcb->asoc.authinfo.assoc_key);
1208 stcb->asoc.authinfo.assoc_key = NULL;
1209 }
1210 if (keyid == stcb->asoc.authinfo.recv_keyid) {
1211 sctp_free_key(stcb->asoc.authinfo.recv_key);
1212 stcb->asoc.authinfo.recv_key = NULL;
1213 }
1214 }
1215
1216 /*-
1217 * clear any cached key(s) if they match the given key id for all assocs on
1218 * an endpoint.
1219 * ASSUMES INP_WLOCK is already held
1220 */
1221 void
1222 sctp_clear_cachedkeys_ep(struct sctp_inpcb *inp, uint16_t keyid)
1223 {
1224 struct sctp_tcb *stcb;
1225
1226 if (inp == NULL)
1227 return;
1228
1229 /* clear the cached keys on all assocs on this instance */
1230 LIST_FOREACH(stcb, &inp->sctp_asoc_list, sctp_tcblist) {
1231 SCTP_TCB_LOCK(stcb);
1232 sctp_clear_cachedkeys(stcb, keyid);
1233 SCTP_TCB_UNLOCK(stcb);
1234 }
1235 }
1236
1237 /*-
1238 * delete a shared key from an association
1239 * ASSUMES TCB_LOCK is already held
1240 */
1241 int
1242 sctp_delete_sharedkey(struct sctp_tcb *stcb, uint16_t keyid)
1243 {
1244 sctp_sharedkey_t *skey;
1245
1246 if (stcb == NULL)
1247 return (-1);
1248
1249 /* is the keyid the assoc active sending key */
1250 if (keyid == stcb->asoc.authinfo.active_keyid)
1251 return (-1);
1252
1253 /* does the key exist? */
1254 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
1255 if (skey == NULL)
1256 return (-1);
1257
1258 /* are there other refcount holders on the key? */
1259 if (skey->refcount > 1)
1260 return (-1);
1261
1262 /* remove it */
1263 LIST_REMOVE(skey, next);
1264 sctp_free_sharedkey(skey); /* frees skey->key as well */
1265
1266 /* clear any cached keys */
1267 sctp_clear_cachedkeys(stcb, keyid);
1268 return (0);
1269 }
1270
1271 /*-
1272 * deletes a shared key from the endpoint
1273 * ASSUMES INP_WLOCK is already held
1274 */
1275 int
1276 sctp_delete_sharedkey_ep(struct sctp_inpcb *inp, uint16_t keyid)
1277 {
1278 sctp_sharedkey_t *skey;
1279
1280 if (inp == NULL)
1281 return (-1);
1282
1283 /* is the keyid the active sending key on the endpoint */
1284 if (keyid == inp->sctp_ep.default_keyid)
1285 return (-1);
1286
1287 /* does the key exist? */
1288 skey = sctp_find_sharedkey(&inp->sctp_ep.shared_keys, keyid);
1289 if (skey == NULL)
1290 return (-1);
1291
1292 /* endpoint keys are not refcounted */
1293
1294 /* remove it */
1295 LIST_REMOVE(skey, next);
1296 sctp_free_sharedkey(skey); /* frees skey->key as well */
1297
1298 /* clear any cached keys */
1299 sctp_clear_cachedkeys_ep(inp, keyid);
1300 return (0);
1301 }
1302
1303 /*-
1304 * set the active key on an association
1305 * ASSUMES TCB_LOCK is already held
1306 */
1307 int
1308 sctp_auth_setactivekey(struct sctp_tcb *stcb, uint16_t keyid)
1309 {
1310 sctp_sharedkey_t *skey = NULL;
1311
1312 /* find the key on the assoc */
1313 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
1314 if (skey == NULL) {
1315 /* that key doesn't exist */
1316 return (-1);
1317 }
1318 if ((skey->deactivated) && (skey->refcount > 1)) {
1319 /* can't reactivate a deactivated key with other refcounts */
1320 return (-1);
1321 }
1322 /* set the (new) active key */
1323 stcb->asoc.authinfo.active_keyid = keyid;
1324 /* reset the deactivated flag */
1325 skey->deactivated = 0;
1326
1327 return (0);
1328 }
1329
1330 /*-
1331 * set the active key on an endpoint
1332 * ASSUMES INP_WLOCK is already held
1333 */
1334 int
1335 sctp_auth_setactivekey_ep(struct sctp_inpcb *inp, uint16_t keyid)
1336 {
1337 sctp_sharedkey_t *skey;
1338
1339 /* find the key */
1340 skey = sctp_find_sharedkey(&inp->sctp_ep.shared_keys, keyid);
1341 if (skey == NULL) {
1342 /* that key doesn't exist */
1343 return (-1);
1344 }
1345 inp->sctp_ep.default_keyid = keyid;
1346 return (0);
1347 }
1348
1349 /*-
1350 * deactivates a shared key from the association
1351 * ASSUMES INP_WLOCK is already held
1352 */
1353 int
1354 sctp_deact_sharedkey(struct sctp_tcb *stcb, uint16_t keyid)
1355 {
1356 sctp_sharedkey_t *skey;
1357
1358 if (stcb == NULL)
1359 return (-1);
1360
1361 /* is the keyid the assoc active sending key */
1362 if (keyid == stcb->asoc.authinfo.active_keyid)
1363 return (-1);
1364
1365 /* does the key exist? */
1366 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
1367 if (skey == NULL)
1368 return (-1);
1369
1370 /* are there other refcount holders on the key? */
1371 if (skey->refcount == 1) {
1372 /* no other users, send a notification for this key */
1373 sctp_ulp_notify(SCTP_NOTIFY_AUTH_FREE_KEY, stcb, keyid, 0,
1374 SCTP_SO_LOCKED);
1375 }
1376 /* mark the key as deactivated */
1377 skey->deactivated = 1;
1378
1379 return (0);
1380 }
1381
1382 /*-
1383 * deactivates a shared key from the endpoint
1384 * ASSUMES INP_WLOCK is already held
1385 */
1386 int
1387 sctp_deact_sharedkey_ep(struct sctp_inpcb *inp, uint16_t keyid)
1388 {
1389 sctp_sharedkey_t *skey;
1390
1391 if (inp == NULL)
1392 return (-1);
1393
1394 /* is the keyid the active sending key on the endpoint */
1395 if (keyid == inp->sctp_ep.default_keyid)
1396 return (-1);
1397
1398 /* does the key exist? */
1399 skey = sctp_find_sharedkey(&inp->sctp_ep.shared_keys, keyid);
1400 if (skey == NULL)
1401 return (-1);
1402
1403 /* endpoint keys are not refcounted */
1404
1405 /* remove it */
1406 LIST_REMOVE(skey, next);
1407 sctp_free_sharedkey(skey); /* frees skey->key as well */
1408
1409 return (0);
1410 }
1411
1412 /*
1413 * get local authentication parameters from cookie (from INIT-ACK)
1414 */
1415 void
1416 sctp_auth_get_cookie_params(struct sctp_tcb *stcb, struct mbuf *m,
1417 uint32_t offset, uint32_t length)
1418 {
1419 struct sctp_paramhdr *phdr, tmp_param;
1420 uint16_t plen, ptype;
1421 uint8_t random_store[SCTP_PARAM_BUFFER_SIZE];
1422 struct sctp_auth_random *p_random = NULL;
1423 uint16_t random_len = 0;
1424 uint8_t hmacs_store[SCTP_PARAM_BUFFER_SIZE];
1425 struct sctp_auth_hmac_algo *hmacs = NULL;
1426 uint16_t hmacs_len = 0;
1427 uint8_t chunks_store[SCTP_PARAM_BUFFER_SIZE];
1428 struct sctp_auth_chunk_list *chunks = NULL;
1429 uint16_t num_chunks = 0;
1430 sctp_key_t *new_key;
1431 uint32_t keylen;
1432
1433 /* convert to upper bound */
1434 length += offset;
1435
1436 phdr = (struct sctp_paramhdr *)sctp_m_getptr(m, offset,
1437 sizeof(struct sctp_paramhdr), (uint8_t *) & tmp_param);
1438 while (phdr != NULL) {
1439 ptype = ntohs(phdr->param_type);
1440 plen = ntohs(phdr->param_length);
1441
1442 if ((plen == 0) || (offset + plen > length))
1443 break;
1444
1445 if (ptype == SCTP_RANDOM) {
1446 if (plen > sizeof(random_store))
1447 break;
1448 phdr = sctp_get_next_param(m, offset,
1449 (struct sctp_paramhdr *)random_store, min(plen, sizeof(random_store)));
1450 if (phdr == NULL)
1451 return;
1452 /* save the random and length for the key */
1453 p_random = (struct sctp_auth_random *)phdr;
1454 random_len = plen - sizeof(*p_random);
1455 } else if (ptype == SCTP_HMAC_LIST) {
1456 int num_hmacs;
1457 int i;
1458
1459 if (plen > sizeof(hmacs_store))
1460 break;
1461 phdr = sctp_get_next_param(m, offset,
1462 (struct sctp_paramhdr *)hmacs_store, min(plen, sizeof(hmacs_store)));
1463 if (phdr == NULL)
1464 return;
1465 /* save the hmacs list and num for the key */
1466 hmacs = (struct sctp_auth_hmac_algo *)phdr;
1467 hmacs_len = plen - sizeof(*hmacs);
1468 num_hmacs = hmacs_len / sizeof(hmacs->hmac_ids[0]);
1469 if (stcb->asoc.local_hmacs != NULL)
1470 sctp_free_hmaclist(stcb->asoc.local_hmacs);
1471 stcb->asoc.local_hmacs = sctp_alloc_hmaclist(num_hmacs);
1472 if (stcb->asoc.local_hmacs != NULL) {
1473 for (i = 0; i < num_hmacs; i++) {
1474 (void)sctp_auth_add_hmacid(stcb->asoc.local_hmacs,
1475 ntohs(hmacs->hmac_ids[i]));
1476 }
1477 }
1478 } else if (ptype == SCTP_CHUNK_LIST) {
1479 int i;
1480
1481 if (plen > sizeof(chunks_store))
1482 break;
1483 phdr = sctp_get_next_param(m, offset,
1484 (struct sctp_paramhdr *)chunks_store, min(plen, sizeof(chunks_store)));
1485 if (phdr == NULL)
1486 return;
1487 chunks = (struct sctp_auth_chunk_list *)phdr;
1488 num_chunks = plen - sizeof(*chunks);
1489 /* save chunks list and num for the key */
1490 if (stcb->asoc.local_auth_chunks != NULL)
1491 sctp_clear_chunklist(stcb->asoc.local_auth_chunks);
1492 else
1493 stcb->asoc.local_auth_chunks = sctp_alloc_chunklist();
1494 for (i = 0; i < num_chunks; i++) {
1495 (void)sctp_auth_add_chunk(chunks->chunk_types[i],
1496 stcb->asoc.local_auth_chunks);
1497 }
1498 }
1499 /* get next parameter */
1500 offset += SCTP_SIZE32(plen);
1501 if (offset + sizeof(struct sctp_paramhdr) > length)
1502 break;
1503 phdr = (struct sctp_paramhdr *)sctp_m_getptr(m, offset, sizeof(struct sctp_paramhdr),
1504 (uint8_t *) & tmp_param);
1505 }
1506 /* concatenate the full random key */
1507 keylen = sizeof(*p_random) + random_len + sizeof(*hmacs) + hmacs_len;
1508 if (chunks != NULL) {
1509 keylen += sizeof(*chunks) + num_chunks;
1510 }
1511 new_key = sctp_alloc_key(keylen);
1512 if (new_key != NULL) {
1513 /* copy in the RANDOM */
1514 if (p_random != NULL) {
1515 keylen = sizeof(*p_random) + random_len;
1516 bcopy(p_random, new_key->key, keylen);
1517 }
1518 /* append in the AUTH chunks */
1519 if (chunks != NULL) {
1520 bcopy(chunks, new_key->key + keylen,
1521 sizeof(*chunks) + num_chunks);
1522 keylen += sizeof(*chunks) + num_chunks;
1523 }
1524 /* append in the HMACs */
1525 if (hmacs != NULL) {
1526 bcopy(hmacs, new_key->key + keylen,
1527 sizeof(*hmacs) + hmacs_len);
1528 }
1529 }
1530 if (stcb->asoc.authinfo.random != NULL)
1531 sctp_free_key(stcb->asoc.authinfo.random);
1532 stcb->asoc.authinfo.random = new_key;
1533 stcb->asoc.authinfo.random_len = random_len;
1534 sctp_clear_cachedkeys(stcb, stcb->asoc.authinfo.assoc_keyid);
1535 sctp_clear_cachedkeys(stcb, stcb->asoc.authinfo.recv_keyid);
1536
1537 /* negotiate what HMAC to use for the peer */
1538 stcb->asoc.peer_hmac_id = sctp_negotiate_hmacid(stcb->asoc.peer_hmacs,
1539 stcb->asoc.local_hmacs);
1540
1541 /* copy defaults from the endpoint */
1542 /* FIX ME: put in cookie? */
1543 stcb->asoc.authinfo.active_keyid = stcb->sctp_ep->sctp_ep.default_keyid;
1544 /* copy out the shared key list (by reference) from the endpoint */
1545 (void)sctp_copy_skeylist(&stcb->sctp_ep->sctp_ep.shared_keys,
1546 &stcb->asoc.shared_keys);
1547 }
1548
1549 /*
1550 * compute and fill in the HMAC digest for a packet
1551 */
1552 void
1553 sctp_fill_hmac_digest_m(struct mbuf *m, uint32_t auth_offset,
1554 struct sctp_auth_chunk *auth, struct sctp_tcb *stcb, uint16_t keyid)
1555 {
1556 uint32_t digestlen;
1557 sctp_sharedkey_t *skey;
1558 sctp_key_t *key;
1559
1560 if ((stcb == NULL) || (auth == NULL))
1561 return;
1562
1563 /* zero the digest + chunk padding */
1564 digestlen = sctp_get_hmac_digest_len(stcb->asoc.peer_hmac_id);
1565 bzero(auth->hmac, SCTP_SIZE32(digestlen));
1566
1567 /* is the desired key cached? */
1568 if ((keyid != stcb->asoc.authinfo.assoc_keyid) ||
1569 (stcb->asoc.authinfo.assoc_key == NULL)) {
1570 if (stcb->asoc.authinfo.assoc_key != NULL) {
1571 /* free the old cached key */
1572 sctp_free_key(stcb->asoc.authinfo.assoc_key);
1573 }
1574 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
1575 /* the only way skey is NULL is if null key id 0 is used */
1576 if (skey != NULL)
1577 key = skey->key;
1578 else
1579 key = NULL;
1580 /* compute a new assoc key and cache it */
1581 stcb->asoc.authinfo.assoc_key =
1582 sctp_compute_hashkey(stcb->asoc.authinfo.random,
1583 stcb->asoc.authinfo.peer_random, key);
1584 stcb->asoc.authinfo.assoc_keyid = keyid;
1585 SCTPDBG(SCTP_DEBUG_AUTH1, "caching key id %u\n",
1586 stcb->asoc.authinfo.assoc_keyid);
1587 #ifdef SCTP_DEBUG
1588 if (SCTP_AUTH_DEBUG)
1589 sctp_print_key(stcb->asoc.authinfo.assoc_key,
1590 "Assoc Key");
1591 #endif
1592 }
1593 /* set in the active key id */
1594 auth->shared_key_id = htons(keyid);
1595
1596 /* compute and fill in the digest */
1597 (void)sctp_compute_hmac_m(stcb->asoc.peer_hmac_id, stcb->asoc.authinfo.assoc_key,
1598 m, auth_offset, auth->hmac);
1599 }
1600
1601
1602 static void
1603 sctp_bzero_m(struct mbuf *m, uint32_t m_offset, uint32_t size)
1604 {
1605 struct mbuf *m_tmp;
1606 uint8_t *data;
1607
1608 /* sanity check */
1609 if (m == NULL)
1610 return;
1611
1612 /* find the correct starting mbuf and offset (get start position) */
1613 m_tmp = m;
1614 while ((m_tmp != NULL) && (m_offset >= (uint32_t) SCTP_BUF_LEN(m_tmp))) {
1615 m_offset -= SCTP_BUF_LEN(m_tmp);
1616 m_tmp = SCTP_BUF_NEXT(m_tmp);
1617 }
1618 /* now use the rest of the mbuf chain */
1619 while ((m_tmp != NULL) && (size > 0)) {
1620 data = mtod(m_tmp, uint8_t *) + m_offset;
1621 if (size > (uint32_t) SCTP_BUF_LEN(m_tmp)) {
1622 bzero(data, SCTP_BUF_LEN(m_tmp));
1623 size -= SCTP_BUF_LEN(m_tmp);
1624 } else {
1625 bzero(data, size);
1626 size = 0;
1627 }
1628 /* clear the offset since it's only for the first mbuf */
1629 m_offset = 0;
1630 m_tmp = SCTP_BUF_NEXT(m_tmp);
1631 }
1632 }
1633
1634 /*-
1635 * process the incoming Authentication chunk
1636 * return codes:
1637 * -1 on any authentication error
1638 * 0 on authentication verification
1639 */
1640 int
1641 sctp_handle_auth(struct sctp_tcb *stcb, struct sctp_auth_chunk *auth,
1642 struct mbuf *m, uint32_t offset)
1643 {
1644 uint16_t chunklen;
1645 uint16_t shared_key_id;
1646 uint16_t hmac_id;
1647 sctp_sharedkey_t *skey;
1648 uint32_t digestlen;
1649 uint8_t digest[SCTP_AUTH_DIGEST_LEN_MAX];
1650 uint8_t computed_digest[SCTP_AUTH_DIGEST_LEN_MAX];
1651
1652 /* auth is checked for NULL by caller */
1653 chunklen = ntohs(auth->ch.chunk_length);
1654 if (chunklen < sizeof(*auth)) {
1655 SCTP_STAT_INCR(sctps_recvauthfailed);
1656 return (-1);
1657 }
1658 SCTP_STAT_INCR(sctps_recvauth);
1659
1660 /* get the auth params */
1661 shared_key_id = ntohs(auth->shared_key_id);
1662 hmac_id = ntohs(auth->hmac_id);
1663 SCTPDBG(SCTP_DEBUG_AUTH1,
1664 "SCTP AUTH Chunk: shared key %u, HMAC id %u\n",
1665 shared_key_id, hmac_id);
1666
1667 /* is the indicated HMAC supported? */
1668 if (!sctp_auth_is_supported_hmac(stcb->asoc.local_hmacs, hmac_id)) {
1669 struct mbuf *m_err;
1670 struct sctp_auth_invalid_hmac *err;
1671
1672 SCTP_STAT_INCR(sctps_recvivalhmacid);
1673 SCTPDBG(SCTP_DEBUG_AUTH1,
1674 "SCTP Auth: unsupported HMAC id %u\n",
1675 hmac_id);
1676 /*
1677 * report this in an Error Chunk: Unsupported HMAC
1678 * Identifier
1679 */
1680 m_err = sctp_get_mbuf_for_msg(sizeof(*err), 0, M_NOWAIT,
1681 1, MT_HEADER);
1682 if (m_err != NULL) {
1683 /* pre-reserve some space */
1684 SCTP_BUF_RESV_UF(m_err, sizeof(struct sctp_chunkhdr));
1685 /* fill in the error */
1686 err = mtod(m_err, struct sctp_auth_invalid_hmac *);
1687 bzero(err, sizeof(*err));
1688 err->ph.param_type = htons(SCTP_CAUSE_UNSUPPORTED_HMACID);
1689 err->ph.param_length = htons(sizeof(*err));
1690 err->hmac_id = ntohs(hmac_id);
1691 SCTP_BUF_LEN(m_err) = sizeof(*err);
1692 /* queue it */
1693 sctp_queue_op_err(stcb, m_err);
1694 }
1695 return (-1);
1696 }
1697 /* get the indicated shared key, if available */
1698 if ((stcb->asoc.authinfo.recv_key == NULL) ||
1699 (stcb->asoc.authinfo.recv_keyid != shared_key_id)) {
1700 /* find the shared key on the assoc first */
1701 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys,
1702 shared_key_id);
1703 /* if the shared key isn't found, discard the chunk */
1704 if (skey == NULL) {
1705 SCTP_STAT_INCR(sctps_recvivalkeyid);
1706 SCTPDBG(SCTP_DEBUG_AUTH1,
1707 "SCTP Auth: unknown key id %u\n",
1708 shared_key_id);
1709 return (-1);
1710 }
1711 /* generate a notification if this is a new key id */
1712 if (stcb->asoc.authinfo.recv_keyid != shared_key_id)
1713 /*
1714 * sctp_ulp_notify(SCTP_NOTIFY_AUTH_NEW_KEY, stcb,
1715 * shared_key_id, (void
1716 * *)stcb->asoc.authinfo.recv_keyid);
1717 */
1718 sctp_notify_authentication(stcb, SCTP_AUTH_NEW_KEY,
1719 shared_key_id, stcb->asoc.authinfo.recv_keyid,
1720 SCTP_SO_NOT_LOCKED);
1721 /* compute a new recv assoc key and cache it */
1722 if (stcb->asoc.authinfo.recv_key != NULL)
1723 sctp_free_key(stcb->asoc.authinfo.recv_key);
1724 stcb->asoc.authinfo.recv_key =
1725 sctp_compute_hashkey(stcb->asoc.authinfo.random,
1726 stcb->asoc.authinfo.peer_random, skey->key);
1727 stcb->asoc.authinfo.recv_keyid = shared_key_id;
1728 #ifdef SCTP_DEBUG
1729 if (SCTP_AUTH_DEBUG)
1730 sctp_print_key(stcb->asoc.authinfo.recv_key, "Recv Key");
1731 #endif
1732 }
1733 /* validate the digest length */
1734 digestlen = sctp_get_hmac_digest_len(hmac_id);
1735 if (chunklen < (sizeof(*auth) + digestlen)) {
1736 /* invalid digest length */
1737 SCTP_STAT_INCR(sctps_recvauthfailed);
1738 SCTPDBG(SCTP_DEBUG_AUTH1,
1739 "SCTP Auth: chunk too short for HMAC\n");
1740 return (-1);
1741 }
1742 /* save a copy of the digest, zero the pseudo header, and validate */
1743 bcopy(auth->hmac, digest, digestlen);
1744 sctp_bzero_m(m, offset + sizeof(*auth), SCTP_SIZE32(digestlen));
1745 (void)sctp_compute_hmac_m(hmac_id, stcb->asoc.authinfo.recv_key,
1746 m, offset, computed_digest);
1747
1748 /* compare the computed digest with the one in the AUTH chunk */
1749 if (memcmp(digest, computed_digest, digestlen) != 0) {
1750 SCTP_STAT_INCR(sctps_recvauthfailed);
1751 SCTPDBG(SCTP_DEBUG_AUTH1,
1752 "SCTP Auth: HMAC digest check failed\n");
1753 return (-1);
1754 }
1755 return (0);
1756 }
1757
1758 /*
1759 * Generate NOTIFICATION
1760 */
1761 void
1762 sctp_notify_authentication(struct sctp_tcb *stcb, uint32_t indication,
1763 uint16_t keyid, uint16_t alt_keyid, int so_locked
1764 #if !defined(__APPLE__) && !defined(SCTP_SO_LOCK_TESTING)
1765 SCTP_UNUSED
1766 #endif
1767 )
1768 {
1769 struct mbuf *m_notify;
1770 struct sctp_authkey_event *auth;
1771 struct sctp_queued_to_read *control;
1772
1773 if ((stcb == NULL) ||
1774 (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) ||
1775 (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_ALLGONE) ||
1776 (stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET)
1777 ) {
1778 /* If the socket is gone we are out of here */
1779 return;
1780 }
1781 if (sctp_stcb_is_feature_off(stcb->sctp_ep, stcb, SCTP_PCB_FLAGS_AUTHEVNT))
1782 /* event not enabled */
1783 return;
1784
1785 m_notify = sctp_get_mbuf_for_msg(sizeof(struct sctp_authkey_event),
1786 0, M_NOWAIT, 1, MT_HEADER);
1787 if (m_notify == NULL)
1788 /* no space left */
1789 return;
1790
1791 SCTP_BUF_LEN(m_notify) = 0;
1792 auth = mtod(m_notify, struct sctp_authkey_event *);
1793 memset(auth, 0, sizeof(struct sctp_authkey_event));
1794 auth->auth_type = SCTP_AUTHENTICATION_EVENT;
1795 auth->auth_flags = 0;
1796 auth->auth_length = sizeof(*auth);
1797 auth->auth_keynumber = keyid;
1798 auth->auth_altkeynumber = alt_keyid;
1799 auth->auth_indication = indication;
1800 auth->auth_assoc_id = sctp_get_associd(stcb);
1801
1802 SCTP_BUF_LEN(m_notify) = sizeof(*auth);
1803 SCTP_BUF_NEXT(m_notify) = NULL;
1804
1805 /* append to socket */
1806 control = sctp_build_readq_entry(stcb, stcb->asoc.primary_destination,
1807 0, 0, stcb->asoc.context, 0, 0, 0, m_notify);
1808 if (control == NULL) {
1809 /* no memory */
1810 sctp_m_freem(m_notify);
1811 return;
1812 }
1813 control->spec_flags = M_NOTIFICATION;
1814 control->length = SCTP_BUF_LEN(m_notify);
1815 /* not that we need this */
1816 control->tail_mbuf = m_notify;
1817 sctp_add_to_readq(stcb->sctp_ep, stcb, control,
1818 &stcb->sctp_socket->so_rcv, 1, SCTP_READ_LOCK_NOT_HELD, so_locked);
1819 }
1820
1821
1822 /*-
1823 * validates the AUTHentication related parameters in an INIT/INIT-ACK
1824 * Note: currently only used for INIT as INIT-ACK is handled inline
1825 * with sctp_load_addresses_from_init()
1826 */
1827 int
1828 sctp_validate_init_auth_params(struct mbuf *m, int offset, int limit)
1829 {
1830 struct sctp_paramhdr *phdr, parm_buf;
1831 uint16_t ptype, plen;
1832 int peer_supports_asconf = 0;
1833 int peer_supports_auth = 0;
1834 int got_random = 0, got_hmacs = 0, got_chklist = 0;
1835 uint8_t saw_asconf = 0;
1836 uint8_t saw_asconf_ack = 0;
1837
1838 /* go through each of the params. */
1839 phdr = sctp_get_next_param(m, offset, &parm_buf, sizeof(parm_buf));
1840 while (phdr) {
1841 ptype = ntohs(phdr->param_type);
1842 plen = ntohs(phdr->param_length);
1843
1844 if (offset + plen > limit) {
1845 break;
1846 }
1847 if (plen < sizeof(struct sctp_paramhdr)) {
1848 break;
1849 }
1850 if (ptype == SCTP_SUPPORTED_CHUNK_EXT) {
1851 /* A supported extension chunk */
1852 struct sctp_supported_chunk_types_param *pr_supported;
1853 uint8_t local_store[SCTP_PARAM_BUFFER_SIZE];
1854 int num_ent, i;
1855
1856 phdr = sctp_get_next_param(m, offset,
1857 (struct sctp_paramhdr *)&local_store, min(plen, sizeof(local_store)));
1858 if (phdr == NULL) {
1859 return (-1);
1860 }
1861 pr_supported = (struct sctp_supported_chunk_types_param *)phdr;
1862 num_ent = plen - sizeof(struct sctp_paramhdr);
1863 for (i = 0; i < num_ent; i++) {
1864 switch (pr_supported->chunk_types[i]) {
1865 case SCTP_ASCONF:
1866 case SCTP_ASCONF_ACK:
1867 peer_supports_asconf = 1;
1868 break;
1869 default:
1870 /* one we don't care about */
1871 break;
1872 }
1873 }
1874 } else if (ptype == SCTP_RANDOM) {
1875 got_random = 1;
1876 /* enforce the random length */
1877 if (plen != (sizeof(struct sctp_auth_random) +
1878 SCTP_AUTH_RANDOM_SIZE_REQUIRED)) {
1879 SCTPDBG(SCTP_DEBUG_AUTH1,
1880 "SCTP: invalid RANDOM len\n");
1881 return (-1);
1882 }
1883 } else if (ptype == SCTP_HMAC_LIST) {
1884 uint8_t store[SCTP_PARAM_BUFFER_SIZE];
1885 struct sctp_auth_hmac_algo *hmacs;
1886 int num_hmacs;
1887
1888 if (plen > sizeof(store))
1889 break;
1890 phdr = sctp_get_next_param(m, offset,
1891 (struct sctp_paramhdr *)store, min(plen, sizeof(store)));
1892 if (phdr == NULL)
1893 return (-1);
1894 hmacs = (struct sctp_auth_hmac_algo *)phdr;
1895 num_hmacs = (plen - sizeof(*hmacs)) /
1896 sizeof(hmacs->hmac_ids[0]);
1897 /* validate the hmac list */
1898 if (sctp_verify_hmac_param(hmacs, num_hmacs)) {
1899 SCTPDBG(SCTP_DEBUG_AUTH1,
1900 "SCTP: invalid HMAC param\n");
1901 return (-1);
1902 }
1903 got_hmacs = 1;
1904 } else if (ptype == SCTP_CHUNK_LIST) {
1905 int i, num_chunks;
1906 uint8_t chunks_store[SCTP_SMALL_CHUNK_STORE];
1907
1908 /* did the peer send a non-empty chunk list? */
1909 struct sctp_auth_chunk_list *chunks = NULL;
1910
1911 phdr = sctp_get_next_param(m, offset,
1912 (struct sctp_paramhdr *)chunks_store,
1913 min(plen, sizeof(chunks_store)));
1914 if (phdr == NULL)
1915 return (-1);
1916
1917 /*-
1918 * Flip through the list and mark that the
1919 * peer supports asconf/asconf_ack.
1920 */
1921 chunks = (struct sctp_auth_chunk_list *)phdr;
1922 num_chunks = plen - sizeof(*chunks);
1923 for (i = 0; i < num_chunks; i++) {
1924 /* record asconf/asconf-ack if listed */
1925 if (chunks->chunk_types[i] == SCTP_ASCONF)
1926 saw_asconf = 1;
1927 if (chunks->chunk_types[i] == SCTP_ASCONF_ACK)
1928 saw_asconf_ack = 1;
1929
1930 }
1931 if (num_chunks)
1932 got_chklist = 1;
1933 }
1934 offset += SCTP_SIZE32(plen);
1935 if (offset >= limit) {
1936 break;
1937 }
1938 phdr = sctp_get_next_param(m, offset, &parm_buf,
1939 sizeof(parm_buf));
1940 }
1941 /* validate authentication required parameters */
1942 if (got_random && got_hmacs) {
1943 peer_supports_auth = 1;
1944 } else {
1945 peer_supports_auth = 0;
1946 }
1947 if (!peer_supports_auth && got_chklist) {
1948 SCTPDBG(SCTP_DEBUG_AUTH1,
1949 "SCTP: peer sent chunk list w/o AUTH\n");
1950 return (-1);
1951 }
1952 if (!SCTP_BASE_SYSCTL(sctp_asconf_auth_nochk) && peer_supports_asconf &&
1953 !peer_supports_auth) {
1954 SCTPDBG(SCTP_DEBUG_AUTH1,
1955 "SCTP: peer supports ASCONF but not AUTH\n");
1956 return (-1);
1957 } else if ((peer_supports_asconf) && (peer_supports_auth) &&
1958 ((saw_asconf == 0) || (saw_asconf_ack == 0))) {
1959 return (-2);
1960 }
1961 return (0);
1962 }
1963
1964 void
1965 sctp_initialize_auth_params(struct sctp_inpcb *inp, struct sctp_tcb *stcb)
1966 {
1967 uint16_t chunks_len = 0;
1968 uint16_t hmacs_len = 0;
1969 uint16_t random_len = SCTP_AUTH_RANDOM_SIZE_DEFAULT;
1970 sctp_key_t *new_key;
1971 uint16_t keylen;
1972
1973 /* initialize hmac list from endpoint */
1974 stcb->asoc.local_hmacs = sctp_copy_hmaclist(inp->sctp_ep.local_hmacs);
1975 if (stcb->asoc.local_hmacs != NULL) {
1976 hmacs_len = stcb->asoc.local_hmacs->num_algo *
1977 sizeof(stcb->asoc.local_hmacs->hmac[0]);
1978 }
1979 /* initialize auth chunks list from endpoint */
1980 stcb->asoc.local_auth_chunks =
1981 sctp_copy_chunklist(inp->sctp_ep.local_auth_chunks);
1982 if (stcb->asoc.local_auth_chunks != NULL) {
1983 int i;
1984
1985 for (i = 0; i < 256; i++) {
1986 if (stcb->asoc.local_auth_chunks->chunks[i])
1987 chunks_len++;
1988 }
1989 }
1990 /* copy defaults from the endpoint */
1991 stcb->asoc.authinfo.active_keyid = inp->sctp_ep.default_keyid;
1992
1993 /* copy out the shared key list (by reference) from the endpoint */
1994 (void)sctp_copy_skeylist(&inp->sctp_ep.shared_keys,
1995 &stcb->asoc.shared_keys);
1996
1997 /* now set the concatenated key (random + chunks + hmacs) */
1998 /* key includes parameter headers */
1999 keylen = (3 * sizeof(struct sctp_paramhdr)) + random_len + chunks_len +
2000 hmacs_len;
2001 new_key = sctp_alloc_key(keylen);
2002 if (new_key != NULL) {
2003 struct sctp_paramhdr *ph;
2004 int plen;
2005
2006 /* generate and copy in the RANDOM */
2007 ph = (struct sctp_paramhdr *)new_key->key;
2008 ph->param_type = htons(SCTP_RANDOM);
2009 plen = sizeof(*ph) + random_len;
2010 ph->param_length = htons(plen);
2011 SCTP_READ_RANDOM(new_key->key + sizeof(*ph), random_len);
2012 keylen = plen;
2013
2014 /* append in the AUTH chunks */
2015 /* NOTE: currently we always have chunks to list */
2016 ph = (struct sctp_paramhdr *)(new_key->key + keylen);
2017 ph->param_type = htons(SCTP_CHUNK_LIST);
2018 plen = sizeof(*ph) + chunks_len;
2019 ph->param_length = htons(plen);
2020 keylen += sizeof(*ph);
2021 if (stcb->asoc.local_auth_chunks) {
2022 int i;
2023
2024 for (i = 0; i < 256; i++) {
2025 if (stcb->asoc.local_auth_chunks->chunks[i])
2026 new_key->key[keylen++] = i;
2027 }
2028 }
2029 /* append in the HMACs */
2030 ph = (struct sctp_paramhdr *)(new_key->key + keylen);
2031 ph->param_type = htons(SCTP_HMAC_LIST);
2032 plen = sizeof(*ph) + hmacs_len;
2033 ph->param_length = htons(plen);
2034 keylen += sizeof(*ph);
2035 (void)sctp_serialize_hmaclist(stcb->asoc.local_hmacs,
2036 new_key->key + keylen);
2037 }
2038 if (stcb->asoc.authinfo.random != NULL)
2039 sctp_free_key(stcb->asoc.authinfo.random);
2040 stcb->asoc.authinfo.random = new_key;
2041 stcb->asoc.authinfo.random_len = random_len;
2042 }
Cache object: d17c850071e1d92a3b3e0476404909fe
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