1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 2001-2008, by Cisco Systems, Inc. All rights reserved.
5 * Copyright (c) 2008-2012, by Randall Stewart. All rights reserved.
6 * Copyright (c) 2008-2012, by Michael Tuexen. All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
11 * a) Redistributions of source code must retain the above copyright notice,
12 * this list of conditions and the following disclaimer.
13 *
14 * b) Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the distribution.
17 *
18 * c) Neither the name of Cisco Systems, Inc. nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
24 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
26 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
30 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
31 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
32 * THE POSSIBILITY OF SUCH DAMAGE.
33 */
34
35 #if defined(__FreeBSD__) && !defined(__Userspace__)
36 #include <sys/cdefs.h>
37 __FBSDID("$FreeBSD: head/sys/netinet/sctp_auth.c 362054 2020-06-11 13:34:09Z tuexen $");
38 #endif
39
40 #include <netinet/sctp_os.h>
41 #include <netinet/sctp.h>
42 #include <netinet/sctp_header.h>
43 #include <netinet/sctp_pcb.h>
44 #include <netinet/sctp_var.h>
45 #include <netinet/sctp_sysctl.h>
46 #include <netinet/sctputil.h>
47 #include <netinet/sctp_indata.h>
48 #include <netinet/sctp_output.h>
49 #include <netinet/sctp_auth.h>
50
51 #ifdef SCTP_DEBUG
52 #define SCTP_AUTH_DEBUG (SCTP_BASE_SYSCTL(sctp_debug_on) & SCTP_DEBUG_AUTH1)
53 #define SCTP_AUTH_DEBUG2 (SCTP_BASE_SYSCTL(sctp_debug_on) & SCTP_DEBUG_AUTH2)
54 #endif /* SCTP_DEBUG */
55
56
57 void
sctp_clear_chunklist(sctp_auth_chklist_t * chklist)58 sctp_clear_chunklist(sctp_auth_chklist_t *chklist)
59 {
60 memset(chklist, 0, sizeof(*chklist));
61 /* chklist->num_chunks = 0; */
62 }
63
64 sctp_auth_chklist_t *
sctp_alloc_chunklist(void)65 sctp_alloc_chunklist(void)
66 {
67 sctp_auth_chklist_t *chklist;
68
69 SCTP_MALLOC(chklist, sctp_auth_chklist_t *, sizeof(*chklist),
70 SCTP_M_AUTH_CL);
71 if (chklist == NULL) {
72 SCTPDBG(SCTP_DEBUG_AUTH1, "sctp_alloc_chunklist: failed to get memory!\n");
73 } else {
74 sctp_clear_chunklist(chklist);
75 }
76 return (chklist);
77 }
78
79 void
sctp_free_chunklist(sctp_auth_chklist_t * list)80 sctp_free_chunklist(sctp_auth_chklist_t *list)
81 {
82 if (list != NULL)
83 SCTP_FREE(list, SCTP_M_AUTH_CL);
84 }
85
86 sctp_auth_chklist_t *
sctp_copy_chunklist(sctp_auth_chklist_t * list)87 sctp_copy_chunklist(sctp_auth_chklist_t *list)
88 {
89 sctp_auth_chklist_t *new_list;
90
91 if (list == NULL)
92 return (NULL);
93
94 /* get a new list */
95 new_list = sctp_alloc_chunklist();
96 if (new_list == NULL)
97 return (NULL);
98 /* copy it */
99 memcpy(new_list, list, sizeof(*new_list));
100
101 return (new_list);
102 }
103
104
105 /*
106 * add a chunk to the required chunks list
107 */
108 int
sctp_auth_add_chunk(uint8_t chunk,sctp_auth_chklist_t * list)109 sctp_auth_add_chunk(uint8_t chunk, sctp_auth_chklist_t *list)
110 {
111 if (list == NULL)
112 return (-1);
113
114 /* is chunk restricted? */
115 if ((chunk == SCTP_INITIATION) ||
116 (chunk == SCTP_INITIATION_ACK) ||
117 (chunk == SCTP_SHUTDOWN_COMPLETE) ||
118 (chunk == SCTP_AUTHENTICATION)) {
119 return (-1);
120 }
121 if (list->chunks[chunk] == 0) {
122 list->chunks[chunk] = 1;
123 list->num_chunks++;
124 SCTPDBG(SCTP_DEBUG_AUTH1,
125 "SCTP: added chunk %u (0x%02x) to Auth list\n",
126 chunk, chunk);
127 }
128 return (0);
129 }
130
131 /*
132 * delete a chunk from the required chunks list
133 */
134 int
sctp_auth_delete_chunk(uint8_t chunk,sctp_auth_chklist_t * list)135 sctp_auth_delete_chunk(uint8_t chunk, sctp_auth_chklist_t *list)
136 {
137 if (list == NULL)
138 return (-1);
139
140 if (list->chunks[chunk] == 1) {
141 list->chunks[chunk] = 0;
142 list->num_chunks--;
143 SCTPDBG(SCTP_DEBUG_AUTH1,
144 "SCTP: deleted chunk %u (0x%02x) from Auth list\n",
145 chunk, chunk);
146 }
147 return (0);
148 }
149
150 size_t
sctp_auth_get_chklist_size(const sctp_auth_chklist_t * list)151 sctp_auth_get_chklist_size(const sctp_auth_chklist_t *list)
152 {
153 if (list == NULL)
154 return (0);
155 else
156 return (list->num_chunks);
157 }
158
159 /*
160 * return the current number and list of required chunks caller must
161 * guarantee ptr has space for up to 256 bytes
162 */
163 int
sctp_serialize_auth_chunks(const sctp_auth_chklist_t * list,uint8_t * ptr)164 sctp_serialize_auth_chunks(const sctp_auth_chklist_t *list, uint8_t *ptr)
165 {
166 int i, count = 0;
167
168 if (list == NULL)
169 return (0);
170
171 for (i = 0; i < 256; i++) {
172 if (list->chunks[i] != 0) {
173 *ptr++ = i;
174 count++;
175 }
176 }
177 return (count);
178 }
179
180 int
sctp_pack_auth_chunks(const sctp_auth_chklist_t * list,uint8_t * ptr)181 sctp_pack_auth_chunks(const sctp_auth_chklist_t *list, uint8_t *ptr)
182 {
183 int i, size = 0;
184
185 if (list == NULL)
186 return (0);
187
188 if (list->num_chunks <= 32) {
189 /* just list them, one byte each */
190 for (i = 0; i < 256; i++) {
191 if (list->chunks[i] != 0) {
192 *ptr++ = i;
193 size++;
194 }
195 }
196 } else {
197 int index, offset;
198
199 /* pack into a 32 byte bitfield */
200 for (i = 0; i < 256; i++) {
201 if (list->chunks[i] != 0) {
202 index = i / 8;
203 offset = i % 8;
204 ptr[index] |= (1 << offset);
205 }
206 }
207 size = 32;
208 }
209 return (size);
210 }
211
212 int
sctp_unpack_auth_chunks(const uint8_t * ptr,uint8_t num_chunks,sctp_auth_chklist_t * list)213 sctp_unpack_auth_chunks(const uint8_t *ptr, uint8_t num_chunks,
214 sctp_auth_chklist_t *list)
215 {
216 int i;
217 int size;
218
219 if (list == NULL)
220 return (0);
221
222 if (num_chunks <= 32) {
223 /* just pull them, one byte each */
224 for (i = 0; i < num_chunks; i++) {
225 (void)sctp_auth_add_chunk(*ptr++, list);
226 }
227 size = num_chunks;
228 } else {
229 int index, offset;
230
231 /* unpack from a 32 byte bitfield */
232 for (index = 0; index < 32; index++) {
233 for (offset = 0; offset < 8; offset++) {
234 if (ptr[index] & (1 << offset)) {
235 (void)sctp_auth_add_chunk((index * 8) + offset, list);
236 }
237 }
238 }
239 size = 32;
240 }
241 return (size);
242 }
243
244
245 /*
246 * allocate structure space for a key of length keylen
247 */
248 sctp_key_t *
sctp_alloc_key(uint32_t keylen)249 sctp_alloc_key(uint32_t keylen)
250 {
251 sctp_key_t *new_key;
252
253 SCTP_MALLOC(new_key, sctp_key_t *, sizeof(*new_key) + keylen,
254 SCTP_M_AUTH_KY);
255 if (new_key == NULL) {
256 /* out of memory */
257 return (NULL);
258 }
259 new_key->keylen = keylen;
260 return (new_key);
261 }
262
263 void
sctp_free_key(sctp_key_t * key)264 sctp_free_key(sctp_key_t *key)
265 {
266 if (key != NULL)
267 SCTP_FREE(key,SCTP_M_AUTH_KY);
268 }
269
270 void
sctp_print_key(sctp_key_t * key,const char * str)271 sctp_print_key(sctp_key_t *key, const char *str)
272 {
273 uint32_t i;
274
275 if (key == NULL) {
276 SCTP_PRINTF("%s: [Null key]\n", str);
277 return;
278 }
279 SCTP_PRINTF("%s: len %u, ", str, key->keylen);
280 if (key->keylen) {
281 for (i = 0; i < key->keylen; i++)
282 SCTP_PRINTF("%02x", key->key[i]);
283 SCTP_PRINTF("\n");
284 } else {
285 SCTP_PRINTF("[Null key]\n");
286 }
287 }
288
289 void
sctp_show_key(sctp_key_t * key,const char * str)290 sctp_show_key(sctp_key_t *key, const char *str)
291 {
292 uint32_t i;
293
294 if (key == NULL) {
295 SCTP_PRINTF("%s: [Null key]\n", str);
296 return;
297 }
298 SCTP_PRINTF("%s: len %u, ", str, key->keylen);
299 if (key->keylen) {
300 for (i = 0; i < key->keylen; i++)
301 SCTP_PRINTF("%02x", key->key[i]);
302 SCTP_PRINTF("\n");
303 } else {
304 SCTP_PRINTF("[Null key]\n");
305 }
306 }
307
308 static uint32_t
sctp_get_keylen(sctp_key_t * key)309 sctp_get_keylen(sctp_key_t *key)
310 {
311 if (key != NULL)
312 return (key->keylen);
313 else
314 return (0);
315 }
316
317 /*
318 * generate a new random key of length 'keylen'
319 */
320 sctp_key_t *
sctp_generate_random_key(uint32_t keylen)321 sctp_generate_random_key(uint32_t keylen)
322 {
323 sctp_key_t *new_key;
324
325 new_key = sctp_alloc_key(keylen);
326 if (new_key == NULL) {
327 /* out of memory */
328 return (NULL);
329 }
330 SCTP_READ_RANDOM(new_key->key, keylen);
331 new_key->keylen = keylen;
332 return (new_key);
333 }
334
335 sctp_key_t *
sctp_set_key(uint8_t * key,uint32_t keylen)336 sctp_set_key(uint8_t *key, uint32_t keylen)
337 {
338 sctp_key_t *new_key;
339
340 new_key = sctp_alloc_key(keylen);
341 if (new_key == NULL) {
342 /* out of memory */
343 return (NULL);
344 }
345 memcpy(new_key->key, key, keylen);
346 return (new_key);
347 }
348
349 /*-
350 * given two keys of variable size, compute which key is "larger/smaller"
351 * returns: 1 if key1 > key2
352 * -1 if key1 < key2
353 * 0 if key1 = key2
354 */
355 static int
sctp_compare_key(sctp_key_t * key1,sctp_key_t * key2)356 sctp_compare_key(sctp_key_t *key1, sctp_key_t *key2)
357 {
358 uint32_t maxlen;
359 uint32_t i;
360 uint32_t key1len, key2len;
361 uint8_t *key_1, *key_2;
362 uint8_t val1, val2;
363
364 /* sanity/length check */
365 key1len = sctp_get_keylen(key1);
366 key2len = sctp_get_keylen(key2);
367 if ((key1len == 0) && (key2len == 0))
368 return (0);
369 else if (key1len == 0)
370 return (-1);
371 else if (key2len == 0)
372 return (1);
373
374 if (key1len < key2len) {
375 maxlen = key2len;
376 } else {
377 maxlen = key1len;
378 }
379 key_1 = key1->key;
380 key_2 = key2->key;
381 /* check for numeric equality */
382 for (i = 0; i < maxlen; i++) {
383 /* left-pad with zeros */
384 val1 = (i < (maxlen - key1len)) ? 0 : *(key_1++);
385 val2 = (i < (maxlen - key2len)) ? 0 : *(key_2++);
386 if (val1 > val2) {
387 return (1);
388 } else if (val1 < val2) {
389 return (-1);
390 }
391 }
392 /* keys are equal value, so check lengths */
393 if (key1len == key2len)
394 return (0);
395 else if (key1len < key2len)
396 return (-1);
397 else
398 return (1);
399 }
400
401 /*
402 * generate the concatenated keying material based on the two keys and the
403 * shared key (if available). draft-ietf-tsvwg-auth specifies the specific
404 * order for concatenation
405 */
406 sctp_key_t *
sctp_compute_hashkey(sctp_key_t * key1,sctp_key_t * key2,sctp_key_t * shared)407 sctp_compute_hashkey(sctp_key_t *key1, sctp_key_t *key2, sctp_key_t *shared)
408 {
409 uint32_t keylen;
410 sctp_key_t *new_key;
411 uint8_t *key_ptr;
412
413 keylen = sctp_get_keylen(key1) + sctp_get_keylen(key2) +
414 sctp_get_keylen(shared);
415
416 if (keylen > 0) {
417 /* get space for the new key */
418 new_key = sctp_alloc_key(keylen);
419 if (new_key == NULL) {
420 /* out of memory */
421 return (NULL);
422 }
423 new_key->keylen = keylen;
424 key_ptr = new_key->key;
425 } else {
426 /* all keys empty/null?! */
427 return (NULL);
428 }
429
430 /* concatenate the keys */
431 if (sctp_compare_key(key1, key2) <= 0) {
432 /* key is shared + key1 + key2 */
433 if (sctp_get_keylen(shared)) {
434 memcpy(key_ptr, shared->key, shared->keylen);
435 key_ptr += shared->keylen;
436 }
437 if (sctp_get_keylen(key1)) {
438 memcpy(key_ptr, key1->key, key1->keylen);
439 key_ptr += key1->keylen;
440 }
441 if (sctp_get_keylen(key2)) {
442 memcpy(key_ptr, key2->key, key2->keylen);
443 }
444 } else {
445 /* key is shared + key2 + key1 */
446 if (sctp_get_keylen(shared)) {
447 memcpy(key_ptr, shared->key, shared->keylen);
448 key_ptr += shared->keylen;
449 }
450 if (sctp_get_keylen(key2)) {
451 memcpy(key_ptr, key2->key, key2->keylen);
452 key_ptr += key2->keylen;
453 }
454 if (sctp_get_keylen(key1)) {
455 memcpy(key_ptr, key1->key, key1->keylen);
456 }
457 }
458 return (new_key);
459 }
460
461
462 sctp_sharedkey_t *
sctp_alloc_sharedkey(void)463 sctp_alloc_sharedkey(void)
464 {
465 sctp_sharedkey_t *new_key;
466
467 SCTP_MALLOC(new_key, sctp_sharedkey_t *, sizeof(*new_key),
468 SCTP_M_AUTH_KY);
469 if (new_key == NULL) {
470 /* out of memory */
471 return (NULL);
472 }
473 new_key->keyid = 0;
474 new_key->key = NULL;
475 new_key->refcount = 1;
476 new_key->deactivated = 0;
477 return (new_key);
478 }
479
480 void
sctp_free_sharedkey(sctp_sharedkey_t * skey)481 sctp_free_sharedkey(sctp_sharedkey_t *skey)
482 {
483 if (skey == NULL)
484 return;
485
486 if (SCTP_DECREMENT_AND_CHECK_REFCOUNT(&skey->refcount)) {
487 if (skey->key != NULL)
488 sctp_free_key(skey->key);
489 SCTP_FREE(skey, SCTP_M_AUTH_KY);
490 }
491 }
492
493 sctp_sharedkey_t *
sctp_find_sharedkey(struct sctp_keyhead * shared_keys,uint16_t key_id)494 sctp_find_sharedkey(struct sctp_keyhead *shared_keys, uint16_t key_id)
495 {
496 sctp_sharedkey_t *skey;
497
498 LIST_FOREACH(skey, shared_keys, next) {
499 if (skey->keyid == key_id)
500 return (skey);
501 }
502 return (NULL);
503 }
504
505 int
sctp_insert_sharedkey(struct sctp_keyhead * shared_keys,sctp_sharedkey_t * new_skey)506 sctp_insert_sharedkey(struct sctp_keyhead *shared_keys,
507 sctp_sharedkey_t *new_skey)
508 {
509 sctp_sharedkey_t *skey;
510
511 if ((shared_keys == NULL) || (new_skey == NULL))
512 return (EINVAL);
513
514 /* insert into an empty list? */
515 if (LIST_EMPTY(shared_keys)) {
516 LIST_INSERT_HEAD(shared_keys, new_skey, next);
517 return (0);
518 }
519 /* insert into the existing list, ordered by key id */
520 LIST_FOREACH(skey, shared_keys, next) {
521 if (new_skey->keyid < skey->keyid) {
522 /* insert it before here */
523 LIST_INSERT_BEFORE(skey, new_skey, next);
524 return (0);
525 } else if (new_skey->keyid == skey->keyid) {
526 /* replace the existing key */
527 /* verify this key *can* be replaced */
528 if ((skey->deactivated) || (skey->refcount > 1)) {
529 SCTPDBG(SCTP_DEBUG_AUTH1,
530 "can't replace shared key id %u\n",
531 new_skey->keyid);
532 return (EBUSY);
533 }
534 SCTPDBG(SCTP_DEBUG_AUTH1,
535 "replacing shared key id %u\n",
536 new_skey->keyid);
537 LIST_INSERT_BEFORE(skey, new_skey, next);
538 LIST_REMOVE(skey, next);
539 sctp_free_sharedkey(skey);
540 return (0);
541 }
542 if (LIST_NEXT(skey, next) == NULL) {
543 /* belongs at the end of the list */
544 LIST_INSERT_AFTER(skey, new_skey, next);
545 return (0);
546 }
547 }
548 /* shouldn't reach here */
549 return (EINVAL);
550 }
551
552 void
sctp_auth_key_acquire(struct sctp_tcb * stcb,uint16_t key_id)553 sctp_auth_key_acquire(struct sctp_tcb *stcb, uint16_t key_id)
554 {
555 sctp_sharedkey_t *skey;
556
557 /* find the shared key */
558 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, key_id);
559
560 /* bump the ref count */
561 if (skey) {
562 atomic_add_int(&skey->refcount, 1);
563 SCTPDBG(SCTP_DEBUG_AUTH2,
564 "%s: stcb %p key %u refcount acquire to %d\n",
565 __func__, (void *)stcb, key_id, skey->refcount);
566 }
567 }
568
569 void
sctp_auth_key_release(struct sctp_tcb * stcb,uint16_t key_id,int so_locked)570 sctp_auth_key_release(struct sctp_tcb *stcb, uint16_t key_id, int so_locked)
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 *
sctp_copy_sharedkey(const sctp_sharedkey_t * skey)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
sctp_copy_skeylist(const struct sctp_keyhead * src,struct sctp_keyhead * dest)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 *
sctp_alloc_hmaclist(uint16_t num_hmacs)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
sctp_free_hmaclist(sctp_hmaclist_t * list)655 sctp_free_hmaclist(sctp_hmaclist_t *list)
656 {
657 if (list != NULL) {
658 SCTP_FREE(list,SCTP_M_AUTH_HL);
659 }
660 }
661
662 int
sctp_auth_add_hmacid(sctp_hmaclist_t * list,uint16_t hmac_id)663 sctp_auth_add_hmacid(sctp_hmaclist_t *list, uint16_t hmac_id)
664 {
665 int i;
666 if (list == NULL)
667 return (-1);
668 if (list->num_algo == list->max_algo) {
669 SCTPDBG(SCTP_DEBUG_AUTH1,
670 "SCTP: HMAC id list full, ignoring add %u\n", hmac_id);
671 return (-1);
672 }
673 #if defined(SCTP_SUPPORT_HMAC_SHA256)
674 if ((hmac_id != SCTP_AUTH_HMAC_ID_SHA1) &&
675 (hmac_id != SCTP_AUTH_HMAC_ID_SHA256)) {
676 #else
677 if (hmac_id != SCTP_AUTH_HMAC_ID_SHA1) {
678 #endif
679 return (-1);
680 }
681 /* Now is it already in the list */
682 for (i = 0; i < list->num_algo; i++) {
683 if (list->hmac[i] == hmac_id) {
684 /* already in list */
685 return (-1);
686 }
687 }
688 SCTPDBG(SCTP_DEBUG_AUTH1, "SCTP: add HMAC id %u to list\n", hmac_id);
689 list->hmac[list->num_algo++] = hmac_id;
690 return (0);
691 }
692
693 sctp_hmaclist_t *
694 sctp_copy_hmaclist(sctp_hmaclist_t *list)
695 {
696 sctp_hmaclist_t *new_list;
697 int i;
698
699 if (list == NULL)
700 return (NULL);
701 /* get a new list */
702 new_list = sctp_alloc_hmaclist(list->max_algo);
703 if (new_list == NULL)
704 return (NULL);
705 /* copy it */
706 new_list->max_algo = list->max_algo;
707 new_list->num_algo = list->num_algo;
708 for (i = 0; i < list->num_algo; i++)
709 new_list->hmac[i] = list->hmac[i];
710 return (new_list);
711 }
712
713 sctp_hmaclist_t *
714 sctp_default_supported_hmaclist(void)
715 {
716 sctp_hmaclist_t *new_list;
717
718 #if defined(SCTP_SUPPORT_HMAC_SHA256)
719 new_list = sctp_alloc_hmaclist(2);
720 #else
721 new_list = sctp_alloc_hmaclist(1);
722 #endif
723 if (new_list == NULL)
724 return (NULL);
725 #if defined(SCTP_SUPPORT_HMAC_SHA256)
726 /* We prefer SHA256, so list it first */
727 (void)sctp_auth_add_hmacid(new_list, SCTP_AUTH_HMAC_ID_SHA256);
728 #endif
729 (void)sctp_auth_add_hmacid(new_list, SCTP_AUTH_HMAC_ID_SHA1);
730 return (new_list);
731 }
732
733 /*-
734 * HMAC algos are listed in priority/preference order
735 * find the best HMAC id to use for the peer based on local support
736 */
737 uint16_t
738 sctp_negotiate_hmacid(sctp_hmaclist_t *peer, sctp_hmaclist_t *local)
739 {
740 int i, j;
741
742 if ((local == NULL) || (peer == NULL))
743 return (SCTP_AUTH_HMAC_ID_RSVD);
744
745 for (i = 0; i < peer->num_algo; i++) {
746 for (j = 0; j < local->num_algo; j++) {
747 if (peer->hmac[i] == local->hmac[j]) {
748 /* found the "best" one */
749 SCTPDBG(SCTP_DEBUG_AUTH1,
750 "SCTP: negotiated peer HMAC id %u\n",
751 peer->hmac[i]);
752 return (peer->hmac[i]);
753 }
754 }
755 }
756 /* didn't find one! */
757 return (SCTP_AUTH_HMAC_ID_RSVD);
758 }
759
760 /*-
761 * serialize the HMAC algo list and return space used
762 * caller must guarantee ptr has appropriate space
763 */
764 int
765 sctp_serialize_hmaclist(sctp_hmaclist_t *list, uint8_t *ptr)
766 {
767 int i;
768 uint16_t hmac_id;
769
770 if (list == NULL)
771 return (0);
772
773 for (i = 0; i < list->num_algo; i++) {
774 hmac_id = htons(list->hmac[i]);
775 memcpy(ptr, &hmac_id, sizeof(hmac_id));
776 ptr += sizeof(hmac_id);
777 }
778 return (list->num_algo * sizeof(hmac_id));
779 }
780
781 int
782 sctp_verify_hmac_param (struct sctp_auth_hmac_algo *hmacs, uint32_t num_hmacs)
783 {
784 uint32_t i;
785
786 for (i = 0; i < num_hmacs; i++) {
787 if (ntohs(hmacs->hmac_ids[i]) == SCTP_AUTH_HMAC_ID_SHA1) {
788 return (0);
789 }
790 }
791 return (-1);
792 }
793
794 sctp_authinfo_t *
795 sctp_alloc_authinfo(void)
796 {
797 sctp_authinfo_t *new_authinfo;
798
799 SCTP_MALLOC(new_authinfo, sctp_authinfo_t *, sizeof(*new_authinfo),
800 SCTP_M_AUTH_IF);
801
802 if (new_authinfo == NULL) {
803 /* out of memory */
804 return (NULL);
805 }
806 memset(new_authinfo, 0, sizeof(*new_authinfo));
807 return (new_authinfo);
808 }
809
810 void
811 sctp_free_authinfo(sctp_authinfo_t *authinfo)
812 {
813 if (authinfo == NULL)
814 return;
815
816 if (authinfo->random != NULL)
817 sctp_free_key(authinfo->random);
818 if (authinfo->peer_random != NULL)
819 sctp_free_key(authinfo->peer_random);
820 if (authinfo->assoc_key != NULL)
821 sctp_free_key(authinfo->assoc_key);
822 if (authinfo->recv_key != NULL)
823 sctp_free_key(authinfo->recv_key);
824
825 /* We are NOT dynamically allocating authinfo's right now... */
826 /* SCTP_FREE(authinfo, SCTP_M_AUTH_??); */
827 }
828
829
830 uint32_t
831 sctp_get_auth_chunk_len(uint16_t hmac_algo)
832 {
833 int size;
834
835 size = sizeof(struct sctp_auth_chunk) + sctp_get_hmac_digest_len(hmac_algo);
836 return (SCTP_SIZE32(size));
837 }
838
839 uint32_t
840 sctp_get_hmac_digest_len(uint16_t hmac_algo)
841 {
842 switch (hmac_algo) {
843 case SCTP_AUTH_HMAC_ID_SHA1:
844 return (SCTP_AUTH_DIGEST_LEN_SHA1);
845 #if defined(SCTP_SUPPORT_HMAC_SHA256)
846 case SCTP_AUTH_HMAC_ID_SHA256:
847 return (SCTP_AUTH_DIGEST_LEN_SHA256);
848 #endif
849 default:
850 /* unknown HMAC algorithm: can't do anything */
851 return (0);
852 } /* end switch */
853 }
854
855 static inline int
856 sctp_get_hmac_block_len(uint16_t hmac_algo)
857 {
858 switch (hmac_algo) {
859 case SCTP_AUTH_HMAC_ID_SHA1:
860 return (64);
861 #if defined(SCTP_SUPPORT_HMAC_SHA256)
862 case SCTP_AUTH_HMAC_ID_SHA256:
863 return (64);
864 #endif
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 #if defined(__Userspace__)
873 /* __Userspace__ SHA1_Init is defined in libcrypto.a (libssl-dev on Ubuntu) */
874 #endif
875 static void
876 sctp_hmac_init(uint16_t hmac_algo, sctp_hash_context_t *ctx)
877 {
878 switch (hmac_algo) {
879 case SCTP_AUTH_HMAC_ID_SHA1:
880 SCTP_SHA1_INIT(&ctx->sha1);
881 break;
882 #if defined(SCTP_SUPPORT_HMAC_SHA256)
883 case SCTP_AUTH_HMAC_ID_SHA256:
884 SCTP_SHA256_INIT(&ctx->sha256);
885 break;
886 #endif
887 case SCTP_AUTH_HMAC_ID_RSVD:
888 default:
889 /* unknown HMAC algorithm: can't do anything */
890 return;
891 } /* end switch */
892 }
893
894 static void
895 sctp_hmac_update(uint16_t hmac_algo, sctp_hash_context_t *ctx,
896 uint8_t *text, uint32_t textlen)
897 {
898 switch (hmac_algo) {
899 case SCTP_AUTH_HMAC_ID_SHA1:
900 SCTP_SHA1_UPDATE(&ctx->sha1, text, textlen);
901 break;
902 #if defined(SCTP_SUPPORT_HMAC_SHA256)
903 case SCTP_AUTH_HMAC_ID_SHA256:
904 SCTP_SHA256_UPDATE(&ctx->sha256, text, textlen);
905 break;
906 #endif
907 case SCTP_AUTH_HMAC_ID_RSVD:
908 default:
909 /* unknown HMAC algorithm: can't do anything */
910 return;
911 } /* end switch */
912 }
913
914 static void
915 sctp_hmac_final(uint16_t hmac_algo, sctp_hash_context_t *ctx,
916 uint8_t *digest)
917 {
918 switch (hmac_algo) {
919 case SCTP_AUTH_HMAC_ID_SHA1:
920 SCTP_SHA1_FINAL(digest, &ctx->sha1);
921 break;
922 #if defined(SCTP_SUPPORT_HMAC_SHA256)
923 case SCTP_AUTH_HMAC_ID_SHA256:
924 SCTP_SHA256_FINAL(digest, &ctx->sha256);
925 break;
926 #endif
927 case SCTP_AUTH_HMAC_ID_RSVD:
928 default:
929 /* unknown HMAC algorithm: can't do anything */
930 return;
931 } /* end switch */
932 }
933
934 /*-
935 * Keyed-Hashing for Message Authentication: FIPS 198 (RFC 2104)
936 *
937 * Compute the HMAC digest using the desired hash key, text, and HMAC
938 * algorithm. Resulting digest is placed in 'digest' and digest length
939 * is returned, if the HMAC was performed.
940 *
941 * WARNING: it is up to the caller to supply sufficient space to hold the
942 * resultant digest.
943 */
944 uint32_t
945 sctp_hmac(uint16_t hmac_algo, uint8_t *key, uint32_t keylen,
946 uint8_t *text, uint32_t textlen, uint8_t *digest)
947 {
948 uint32_t digestlen;
949 uint32_t blocklen;
950 sctp_hash_context_t ctx;
951 uint8_t ipad[128], opad[128]; /* keyed hash inner/outer pads */
952 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
953 uint32_t i;
954
955 /* sanity check the material and length */
956 if ((key == NULL) || (keylen == 0) || (text == NULL) ||
957 (textlen == 0) || (digest == NULL)) {
958 /* can't do HMAC with empty key or text or digest store */
959 return (0);
960 }
961 /* validate the hmac algo and get the digest length */
962 digestlen = sctp_get_hmac_digest_len(hmac_algo);
963 if (digestlen == 0)
964 return (0);
965
966 /* hash the key if it is longer than the hash block size */
967 blocklen = sctp_get_hmac_block_len(hmac_algo);
968 if (keylen > blocklen) {
969 sctp_hmac_init(hmac_algo, &ctx);
970 sctp_hmac_update(hmac_algo, &ctx, key, keylen);
971 sctp_hmac_final(hmac_algo, &ctx, temp);
972 /* set the hashed key as the key */
973 keylen = digestlen;
974 key = temp;
975 }
976 /* initialize the inner/outer pads with the key and "append" zeroes */
977 memset(ipad, 0, blocklen);
978 memset(opad, 0, blocklen);
979 memcpy(ipad, key, keylen);
980 memcpy(opad, key, keylen);
981
982 /* XOR the key with ipad and opad values */
983 for (i = 0; i < blocklen; i++) {
984 ipad[i] ^= 0x36;
985 opad[i] ^= 0x5c;
986 }
987
988 /* perform inner hash */
989 sctp_hmac_init(hmac_algo, &ctx);
990 sctp_hmac_update(hmac_algo, &ctx, ipad, blocklen);
991 sctp_hmac_update(hmac_algo, &ctx, text, textlen);
992 sctp_hmac_final(hmac_algo, &ctx, temp);
993
994 /* perform outer hash */
995 sctp_hmac_init(hmac_algo, &ctx);
996 sctp_hmac_update(hmac_algo, &ctx, opad, blocklen);
997 sctp_hmac_update(hmac_algo, &ctx, temp, digestlen);
998 sctp_hmac_final(hmac_algo, &ctx, digest);
999
1000 return (digestlen);
1001 }
1002
1003 /* mbuf version */
1004 uint32_t
1005 sctp_hmac_m(uint16_t hmac_algo, uint8_t *key, uint32_t keylen,
1006 struct mbuf *m, uint32_t m_offset, uint8_t *digest, uint32_t trailer)
1007 {
1008 uint32_t digestlen;
1009 uint32_t blocklen;
1010 sctp_hash_context_t ctx;
1011 uint8_t ipad[128], opad[128]; /* keyed hash inner/outer pads */
1012 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
1013 uint32_t i;
1014 struct mbuf *m_tmp;
1015
1016 /* sanity check the material and length */
1017 if ((key == NULL) || (keylen == 0) || (m == NULL) || (digest == NULL)) {
1018 /* can't do HMAC with empty key or text or digest store */
1019 return (0);
1020 }
1021 /* validate the hmac algo and get the digest length */
1022 digestlen = sctp_get_hmac_digest_len(hmac_algo);
1023 if (digestlen == 0)
1024 return (0);
1025
1026 /* hash the key if it is longer than the hash block size */
1027 blocklen = sctp_get_hmac_block_len(hmac_algo);
1028 if (keylen > blocklen) {
1029 sctp_hmac_init(hmac_algo, &ctx);
1030 sctp_hmac_update(hmac_algo, &ctx, key, keylen);
1031 sctp_hmac_final(hmac_algo, &ctx, temp);
1032 /* set the hashed key as the key */
1033 keylen = digestlen;
1034 key = temp;
1035 }
1036 /* initialize the inner/outer pads with the key and "append" zeroes */
1037 memset(ipad, 0, blocklen);
1038 memset(opad, 0, blocklen);
1039 memcpy(ipad, key, keylen);
1040 memcpy(opad, key, keylen);
1041
1042 /* XOR the key with ipad and opad values */
1043 for (i = 0; i < blocklen; i++) {
1044 ipad[i] ^= 0x36;
1045 opad[i] ^= 0x5c;
1046 }
1047
1048 /* perform inner hash */
1049 sctp_hmac_init(hmac_algo, &ctx);
1050 sctp_hmac_update(hmac_algo, &ctx, ipad, blocklen);
1051 /* find the correct starting mbuf and offset (get start of text) */
1052 m_tmp = m;
1053 while ((m_tmp != NULL) && (m_offset >= (uint32_t) SCTP_BUF_LEN(m_tmp))) {
1054 m_offset -= SCTP_BUF_LEN(m_tmp);
1055 m_tmp = SCTP_BUF_NEXT(m_tmp);
1056 }
1057 /* now use the rest of the mbuf chain for the text */
1058 while (m_tmp != NULL) {
1059 if ((SCTP_BUF_NEXT(m_tmp) == NULL) && trailer) {
1060 sctp_hmac_update(hmac_algo, &ctx, mtod(m_tmp, uint8_t *) + m_offset,
1061 SCTP_BUF_LEN(m_tmp) - (trailer+m_offset));
1062 } else {
1063 sctp_hmac_update(hmac_algo, &ctx, mtod(m_tmp, uint8_t *) + m_offset,
1064 SCTP_BUF_LEN(m_tmp) - m_offset);
1065 }
1066
1067 /* clear the offset since it's only for the first mbuf */
1068 m_offset = 0;
1069 m_tmp = SCTP_BUF_NEXT(m_tmp);
1070 }
1071 sctp_hmac_final(hmac_algo, &ctx, temp);
1072
1073 /* perform outer hash */
1074 sctp_hmac_init(hmac_algo, &ctx);
1075 sctp_hmac_update(hmac_algo, &ctx, opad, blocklen);
1076 sctp_hmac_update(hmac_algo, &ctx, temp, digestlen);
1077 sctp_hmac_final(hmac_algo, &ctx, digest);
1078
1079 return (digestlen);
1080 }
1081
1082 /*
1083 * computes the requested HMAC using a key struct (which may be modified if
1084 * the keylen exceeds the HMAC block len).
1085 */
1086 uint32_t
1087 sctp_compute_hmac(uint16_t hmac_algo, sctp_key_t *key, uint8_t *text,
1088 uint32_t textlen, uint8_t *digest)
1089 {
1090 uint32_t digestlen;
1091 uint32_t blocklen;
1092 sctp_hash_context_t ctx;
1093 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
1094
1095 /* sanity check */
1096 if ((key == NULL) || (text == NULL) || (textlen == 0) ||
1097 (digest == NULL)) {
1098 /* can't do HMAC with empty key or text or digest store */
1099 return (0);
1100 }
1101 /* validate the hmac algo and get the digest length */
1102 digestlen = sctp_get_hmac_digest_len(hmac_algo);
1103 if (digestlen == 0)
1104 return (0);
1105
1106 /* hash the key if it is longer than the hash block size */
1107 blocklen = sctp_get_hmac_block_len(hmac_algo);
1108 if (key->keylen > blocklen) {
1109 sctp_hmac_init(hmac_algo, &ctx);
1110 sctp_hmac_update(hmac_algo, &ctx, key->key, key->keylen);
1111 sctp_hmac_final(hmac_algo, &ctx, temp);
1112 /* save the hashed key as the new key */
1113 key->keylen = digestlen;
1114 memcpy(key->key, temp, key->keylen);
1115 }
1116 return (sctp_hmac(hmac_algo, key->key, key->keylen, text, textlen,
1117 digest));
1118 }
1119
1120 /* mbuf version */
1121 uint32_t
1122 sctp_compute_hmac_m(uint16_t hmac_algo, sctp_key_t *key, struct mbuf *m,
1123 uint32_t m_offset, uint8_t *digest)
1124 {
1125 uint32_t digestlen;
1126 uint32_t blocklen;
1127 sctp_hash_context_t ctx;
1128 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
1129
1130 /* sanity check */
1131 if ((key == NULL) || (m == NULL) || (digest == NULL)) {
1132 /* can't do HMAC with empty key or text or digest store */
1133 return (0);
1134 }
1135 /* validate the hmac algo and get the digest length */
1136 digestlen = sctp_get_hmac_digest_len(hmac_algo);
1137 if (digestlen == 0)
1138 return (0);
1139
1140 /* hash the key if it is longer than the hash block size */
1141 blocklen = sctp_get_hmac_block_len(hmac_algo);
1142 if (key->keylen > blocklen) {
1143 sctp_hmac_init(hmac_algo, &ctx);
1144 sctp_hmac_update(hmac_algo, &ctx, key->key, key->keylen);
1145 sctp_hmac_final(hmac_algo, &ctx, temp);
1146 /* save the hashed key as the new key */
1147 key->keylen = digestlen;
1148 memcpy(key->key, temp, key->keylen);
1149 }
1150 return (sctp_hmac_m(hmac_algo, key->key, key->keylen, m, m_offset, digest, 0));
1151 }
1152
1153 int
1154 sctp_auth_is_supported_hmac(sctp_hmaclist_t *list, uint16_t id)
1155 {
1156 int i;
1157
1158 if ((list == NULL) || (id == SCTP_AUTH_HMAC_ID_RSVD))
1159 return (0);
1160
1161 for (i = 0; i < list->num_algo; i++)
1162 if (list->hmac[i] == id)
1163 return (1);
1164
1165 /* not in the list */
1166 return (0);
1167 }
1168
1169
1170 /*-
1171 * clear any cached key(s) if they match the given key id on an association.
1172 * the cached key(s) will be recomputed and re-cached at next use.
1173 * ASSUMES TCB_LOCK is already held
1174 */
1175 void
1176 sctp_clear_cachedkeys(struct sctp_tcb *stcb, uint16_t keyid)
1177 {
1178 if (stcb == NULL)
1179 return;
1180
1181 if (keyid == stcb->asoc.authinfo.assoc_keyid) {
1182 sctp_free_key(stcb->asoc.authinfo.assoc_key);
1183 stcb->asoc.authinfo.assoc_key = NULL;
1184 }
1185 if (keyid == stcb->asoc.authinfo.recv_keyid) {
1186 sctp_free_key(stcb->asoc.authinfo.recv_key);
1187 stcb->asoc.authinfo.recv_key = NULL;
1188 }
1189 }
1190
1191 /*-
1192 * clear any cached key(s) if they match the given key id for all assocs on
1193 * an endpoint.
1194 * ASSUMES INP_WLOCK is already held
1195 */
1196 void
1197 sctp_clear_cachedkeys_ep(struct sctp_inpcb *inp, uint16_t keyid)
1198 {
1199 struct sctp_tcb *stcb;
1200
1201 if (inp == NULL)
1202 return;
1203
1204 /* clear the cached keys on all assocs on this instance */
1205 LIST_FOREACH(stcb, &inp->sctp_asoc_list, sctp_tcblist) {
1206 SCTP_TCB_LOCK(stcb);
1207 sctp_clear_cachedkeys(stcb, keyid);
1208 SCTP_TCB_UNLOCK(stcb);
1209 }
1210 }
1211
1212 /*-
1213 * delete a shared key from an association
1214 * ASSUMES TCB_LOCK is already held
1215 */
1216 int
1217 sctp_delete_sharedkey(struct sctp_tcb *stcb, uint16_t keyid)
1218 {
1219 sctp_sharedkey_t *skey;
1220
1221 if (stcb == NULL)
1222 return (-1);
1223
1224 /* is the keyid the assoc active sending key */
1225 if (keyid == stcb->asoc.authinfo.active_keyid)
1226 return (-1);
1227
1228 /* does the key exist? */
1229 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
1230 if (skey == NULL)
1231 return (-1);
1232
1233 /* are there other refcount holders on the key? */
1234 if (skey->refcount > 1)
1235 return (-1);
1236
1237 /* remove it */
1238 LIST_REMOVE(skey, next);
1239 sctp_free_sharedkey(skey); /* frees skey->key as well */
1240
1241 /* clear any cached keys */
1242 sctp_clear_cachedkeys(stcb, keyid);
1243 return (0);
1244 }
1245
1246 /*-
1247 * deletes a shared key from the endpoint
1248 * ASSUMES INP_WLOCK is already held
1249 */
1250 int
1251 sctp_delete_sharedkey_ep(struct sctp_inpcb *inp, uint16_t keyid)
1252 {
1253 sctp_sharedkey_t *skey;
1254
1255 if (inp == NULL)
1256 return (-1);
1257
1258 /* is the keyid the active sending key on the endpoint */
1259 if (keyid == inp->sctp_ep.default_keyid)
1260 return (-1);
1261
1262 /* does the key exist? */
1263 skey = sctp_find_sharedkey(&inp->sctp_ep.shared_keys, keyid);
1264 if (skey == NULL)
1265 return (-1);
1266
1267 /* endpoint keys are not refcounted */
1268
1269 /* remove it */
1270 LIST_REMOVE(skey, next);
1271 sctp_free_sharedkey(skey); /* frees skey->key as well */
1272
1273 /* clear any cached keys */
1274 sctp_clear_cachedkeys_ep(inp, keyid);
1275 return (0);
1276 }
1277
1278 /*-
1279 * set the active key on an association
1280 * ASSUMES TCB_LOCK is already held
1281 */
1282 int
1283 sctp_auth_setactivekey(struct sctp_tcb *stcb, uint16_t keyid)
1284 {
1285 sctp_sharedkey_t *skey = NULL;
1286
1287 /* find the key on the assoc */
1288 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
1289 if (skey == NULL) {
1290 /* that key doesn't exist */
1291 return (-1);
1292 }
1293 if ((skey->deactivated) && (skey->refcount > 1)) {
1294 /* can't reactivate a deactivated key with other refcounts */
1295 return (-1);
1296 }
1297
1298 /* set the (new) active key */
1299 stcb->asoc.authinfo.active_keyid = keyid;
1300 /* reset the deactivated flag */
1301 skey->deactivated = 0;
1302
1303 return (0);
1304 }
1305
1306 /*-
1307 * set the active key on an endpoint
1308 * ASSUMES INP_WLOCK is already held
1309 */
1310 int
1311 sctp_auth_setactivekey_ep(struct sctp_inpcb *inp, uint16_t keyid)
1312 {
1313 sctp_sharedkey_t *skey;
1314
1315 /* find the key */
1316 skey = sctp_find_sharedkey(&inp->sctp_ep.shared_keys, keyid);
1317 if (skey == NULL) {
1318 /* that key doesn't exist */
1319 return (-1);
1320 }
1321 inp->sctp_ep.default_keyid = keyid;
1322 return (0);
1323 }
1324
1325 /*-
1326 * deactivates a shared key from the association
1327 * ASSUMES INP_WLOCK is already held
1328 */
1329 int
1330 sctp_deact_sharedkey(struct sctp_tcb *stcb, uint16_t keyid)
1331 {
1332 sctp_sharedkey_t *skey;
1333
1334 if (stcb == NULL)
1335 return (-1);
1336
1337 /* is the keyid the assoc active sending key */
1338 if (keyid == stcb->asoc.authinfo.active_keyid)
1339 return (-1);
1340
1341 /* does the key exist? */
1342 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
1343 if (skey == NULL)
1344 return (-1);
1345
1346 /* are there other refcount holders on the key? */
1347 if (skey->refcount == 1) {
1348 /* no other users, send a notification for this key */
1349 sctp_ulp_notify(SCTP_NOTIFY_AUTH_FREE_KEY, stcb, keyid, 0,
1350 SCTP_SO_LOCKED);
1351 }
1352
1353 /* mark the key as deactivated */
1354 skey->deactivated = 1;
1355
1356 return (0);
1357 }
1358
1359 /*-
1360 * deactivates a shared key from the endpoint
1361 * ASSUMES INP_WLOCK is already held
1362 */
1363 int
1364 sctp_deact_sharedkey_ep(struct sctp_inpcb *inp, uint16_t keyid)
1365 {
1366 sctp_sharedkey_t *skey;
1367
1368 if (inp == NULL)
1369 return (-1);
1370
1371 /* is the keyid the active sending key on the endpoint */
1372 if (keyid == inp->sctp_ep.default_keyid)
1373 return (-1);
1374
1375 /* does the key exist? */
1376 skey = sctp_find_sharedkey(&inp->sctp_ep.shared_keys, keyid);
1377 if (skey == NULL)
1378 return (-1);
1379
1380 /* endpoint keys are not refcounted */
1381
1382 /* remove it */
1383 LIST_REMOVE(skey, next);
1384 sctp_free_sharedkey(skey); /* frees skey->key as well */
1385
1386 return (0);
1387 }
1388
1389 /*
1390 * get local authentication parameters from cookie (from INIT-ACK)
1391 */
1392 void
1393 sctp_auth_get_cookie_params(struct sctp_tcb *stcb, struct mbuf *m,
1394 uint32_t offset, uint32_t length)
1395 {
1396 struct sctp_paramhdr *phdr, tmp_param;
1397 uint16_t plen, ptype;
1398 uint8_t random_store[SCTP_PARAM_BUFFER_SIZE];
1399 struct sctp_auth_random *p_random = NULL;
1400 uint16_t random_len = 0;
1401 uint8_t hmacs_store[SCTP_PARAM_BUFFER_SIZE];
1402 struct sctp_auth_hmac_algo *hmacs = NULL;
1403 uint16_t hmacs_len = 0;
1404 uint8_t chunks_store[SCTP_PARAM_BUFFER_SIZE];
1405 struct sctp_auth_chunk_list *chunks = NULL;
1406 uint16_t num_chunks = 0;
1407 sctp_key_t *new_key;
1408 uint32_t keylen;
1409
1410 /* convert to upper bound */
1411 length += offset;
1412
1413 phdr = (struct sctp_paramhdr *)sctp_m_getptr(m, offset,
1414 sizeof(struct sctp_paramhdr), (uint8_t *)&tmp_param);
1415 while (phdr != NULL) {
1416 ptype = ntohs(phdr->param_type);
1417 plen = ntohs(phdr->param_length);
1418
1419 if ((plen < sizeof(struct sctp_paramhdr)) ||
1420 (offset + plen > length))
1421 break;
1422
1423 if (ptype == SCTP_RANDOM) {
1424 if (plen > sizeof(random_store))
1425 break;
1426 phdr = sctp_get_next_param(m, offset,
1427 (struct sctp_paramhdr *)random_store, plen);
1428 if (phdr == NULL)
1429 return;
1430 /* save the random and length for the key */
1431 p_random = (struct sctp_auth_random *)phdr;
1432 random_len = plen - sizeof(*p_random);
1433 } else if (ptype == SCTP_HMAC_LIST) {
1434 uint16_t num_hmacs;
1435 uint16_t i;
1436
1437 if (plen > sizeof(hmacs_store))
1438 break;
1439 phdr = sctp_get_next_param(m, offset,
1440 (struct sctp_paramhdr *)hmacs_store, plen);
1441 if (phdr == NULL)
1442 return;
1443 /* save the hmacs list and num for the key */
1444 hmacs = (struct sctp_auth_hmac_algo *)phdr;
1445 hmacs_len = plen - sizeof(*hmacs);
1446 num_hmacs = hmacs_len / sizeof(hmacs->hmac_ids[0]);
1447 if (stcb->asoc.local_hmacs != NULL)
1448 sctp_free_hmaclist(stcb->asoc.local_hmacs);
1449 stcb->asoc.local_hmacs = sctp_alloc_hmaclist(num_hmacs);
1450 if (stcb->asoc.local_hmacs != NULL) {
1451 for (i = 0; i < num_hmacs; i++) {
1452 (void)sctp_auth_add_hmacid(stcb->asoc.local_hmacs,
1453 ntohs(hmacs->hmac_ids[i]));
1454 }
1455 }
1456 } else if (ptype == SCTP_CHUNK_LIST) {
1457 int i;
1458
1459 if (plen > sizeof(chunks_store))
1460 break;
1461 phdr = sctp_get_next_param(m, offset,
1462 (struct sctp_paramhdr *)chunks_store, plen);
1463 if (phdr == NULL)
1464 return;
1465 chunks = (struct sctp_auth_chunk_list *)phdr;
1466 num_chunks = plen - sizeof(*chunks);
1467 /* save chunks list and num for the key */
1468 if (stcb->asoc.local_auth_chunks != NULL)
1469 sctp_clear_chunklist(stcb->asoc.local_auth_chunks);
1470 else
1471 stcb->asoc.local_auth_chunks = sctp_alloc_chunklist();
1472 for (i = 0; i < num_chunks; i++) {
1473 (void)sctp_auth_add_chunk(chunks->chunk_types[i],
1474 stcb->asoc.local_auth_chunks);
1475 }
1476 }
1477 /* get next parameter */
1478 offset += SCTP_SIZE32(plen);
1479 if (offset + sizeof(struct sctp_paramhdr) > length)
1480 break;
1481 phdr = (struct sctp_paramhdr *)sctp_m_getptr(m, offset, sizeof(struct sctp_paramhdr),
1482 (uint8_t *)&tmp_param);
1483 }
1484 /* concatenate the full random key */
1485 keylen = sizeof(*p_random) + random_len + sizeof(*hmacs) + hmacs_len;
1486 if (chunks != NULL) {
1487 keylen += sizeof(*chunks) + num_chunks;
1488 }
1489 new_key = sctp_alloc_key(keylen);
1490 if (new_key != NULL) {
1491 /* copy in the RANDOM */
1492 if (p_random != NULL) {
1493 keylen = sizeof(*p_random) + random_len;
1494 memcpy(new_key->key, p_random, keylen);
1495 } else {
1496 keylen = 0;
1497 }
1498 /* append in the AUTH chunks */
1499 if (chunks != NULL) {
1500 memcpy(new_key->key + keylen, chunks,
1501 sizeof(*chunks) + num_chunks);
1502 keylen += sizeof(*chunks) + num_chunks;
1503 }
1504 /* append in the HMACs */
1505 if (hmacs != NULL) {
1506 memcpy(new_key->key + keylen, hmacs,
1507 sizeof(*hmacs) + hmacs_len);
1508 }
1509 }
1510 if (stcb->asoc.authinfo.random != NULL)
1511 sctp_free_key(stcb->asoc.authinfo.random);
1512 stcb->asoc.authinfo.random = new_key;
1513 stcb->asoc.authinfo.random_len = random_len;
1514 sctp_clear_cachedkeys(stcb, stcb->asoc.authinfo.assoc_keyid);
1515 sctp_clear_cachedkeys(stcb, stcb->asoc.authinfo.recv_keyid);
1516
1517 /* negotiate what HMAC to use for the peer */
1518 stcb->asoc.peer_hmac_id = sctp_negotiate_hmacid(stcb->asoc.peer_hmacs,
1519 stcb->asoc.local_hmacs);
1520
1521 /* copy defaults from the endpoint */
1522 /* FIX ME: put in cookie? */
1523 stcb->asoc.authinfo.active_keyid = stcb->sctp_ep->sctp_ep.default_keyid;
1524 /* copy out the shared key list (by reference) from the endpoint */
1525 (void)sctp_copy_skeylist(&stcb->sctp_ep->sctp_ep.shared_keys,
1526 &stcb->asoc.shared_keys);
1527 }
1528
1529 /*
1530 * compute and fill in the HMAC digest for a packet
1531 */
1532 void
1533 sctp_fill_hmac_digest_m(struct mbuf *m, uint32_t auth_offset,
1534 struct sctp_auth_chunk *auth, struct sctp_tcb *stcb, uint16_t keyid)
1535 {
1536 uint32_t digestlen;
1537 sctp_sharedkey_t *skey;
1538 sctp_key_t *key;
1539
1540 if ((stcb == NULL) || (auth == NULL))
1541 return;
1542
1543 /* zero the digest + chunk padding */
1544 digestlen = sctp_get_hmac_digest_len(stcb->asoc.peer_hmac_id);
1545 memset(auth->hmac, 0, SCTP_SIZE32(digestlen));
1546
1547 /* is the desired key cached? */
1548 if ((keyid != stcb->asoc.authinfo.assoc_keyid) ||
1549 (stcb->asoc.authinfo.assoc_key == NULL)) {
1550 if (stcb->asoc.authinfo.assoc_key != NULL) {
1551 /* free the old cached key */
1552 sctp_free_key(stcb->asoc.authinfo.assoc_key);
1553 }
1554 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
1555 /* the only way skey is NULL is if null key id 0 is used */
1556 if (skey != NULL)
1557 key = skey->key;
1558 else
1559 key = NULL;
1560 /* compute a new assoc key and cache it */
1561 stcb->asoc.authinfo.assoc_key =
1562 sctp_compute_hashkey(stcb->asoc.authinfo.random,
1563 stcb->asoc.authinfo.peer_random, key);
1564 stcb->asoc.authinfo.assoc_keyid = keyid;
1565 SCTPDBG(SCTP_DEBUG_AUTH1, "caching key id %u\n",
1566 stcb->asoc.authinfo.assoc_keyid);
1567 #ifdef SCTP_DEBUG
1568 if (SCTP_AUTH_DEBUG)
1569 sctp_print_key(stcb->asoc.authinfo.assoc_key,
1570 "Assoc Key");
1571 #endif
1572 }
1573
1574 /* set in the active key id */
1575 auth->shared_key_id = htons(keyid);
1576
1577 /* compute and fill in the digest */
1578 (void)sctp_compute_hmac_m(stcb->asoc.peer_hmac_id, stcb->asoc.authinfo.assoc_key,
1579 m, auth_offset, auth->hmac);
1580 }
1581
1582
1583 static void
1584 sctp_zero_m(struct mbuf *m, uint32_t m_offset, uint32_t size)
1585 {
1586 struct mbuf *m_tmp;
1587 uint8_t *data;
1588
1589 /* sanity check */
1590 if (m == NULL)
1591 return;
1592
1593 /* find the correct starting mbuf and offset (get start position) */
1594 m_tmp = m;
1595 while ((m_tmp != NULL) && (m_offset >= (uint32_t) SCTP_BUF_LEN(m_tmp))) {
1596 m_offset -= SCTP_BUF_LEN(m_tmp);
1597 m_tmp = SCTP_BUF_NEXT(m_tmp);
1598 }
1599 /* now use the rest of the mbuf chain */
1600 while ((m_tmp != NULL) && (size > 0)) {
1601 data = mtod(m_tmp, uint8_t *) + m_offset;
1602 if (size > (uint32_t)(SCTP_BUF_LEN(m_tmp) - m_offset)) {
1603 memset(data, 0, SCTP_BUF_LEN(m_tmp) - m_offset);
1604 size -= SCTP_BUF_LEN(m_tmp) - m_offset;
1605 } else {
1606 memset(data, 0, size);
1607 size = 0;
1608 }
1609 /* clear the offset since it's only for the first mbuf */
1610 m_offset = 0;
1611 m_tmp = SCTP_BUF_NEXT(m_tmp);
1612 }
1613 }
1614
1615 /*-
1616 * process the incoming Authentication chunk
1617 * return codes:
1618 * -1 on any authentication error
1619 * 0 on authentication verification
1620 */
1621 int
1622 sctp_handle_auth(struct sctp_tcb *stcb, struct sctp_auth_chunk *auth,
1623 struct mbuf *m, uint32_t offset)
1624 {
1625 uint16_t chunklen;
1626 uint16_t shared_key_id;
1627 uint16_t hmac_id;
1628 sctp_sharedkey_t *skey;
1629 uint32_t digestlen;
1630 uint8_t digest[SCTP_AUTH_DIGEST_LEN_MAX];
1631 uint8_t computed_digest[SCTP_AUTH_DIGEST_LEN_MAX];
1632
1633 /* auth is checked for NULL by caller */
1634 chunklen = ntohs(auth->ch.chunk_length);
1635 if (chunklen < sizeof(*auth)) {
1636 SCTP_STAT_INCR(sctps_recvauthfailed);
1637 return (-1);
1638 }
1639 SCTP_STAT_INCR(sctps_recvauth);
1640
1641 /* get the auth params */
1642 shared_key_id = ntohs(auth->shared_key_id);
1643 hmac_id = ntohs(auth->hmac_id);
1644 SCTPDBG(SCTP_DEBUG_AUTH1,
1645 "SCTP AUTH Chunk: shared key %u, HMAC id %u\n",
1646 shared_key_id, hmac_id);
1647
1648 #if defined(__Userspace__)
1649 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
1650 return (0);
1651 #endif
1652 #endif
1653 /* is the indicated HMAC supported? */
1654 if (!sctp_auth_is_supported_hmac(stcb->asoc.local_hmacs, hmac_id)) {
1655 struct mbuf *op_err;
1656 struct sctp_error_auth_invalid_hmac *cause;
1657
1658 SCTP_STAT_INCR(sctps_recvivalhmacid);
1659 SCTPDBG(SCTP_DEBUG_AUTH1,
1660 "SCTP Auth: unsupported HMAC id %u\n",
1661 hmac_id);
1662 /*
1663 * report this in an Error Chunk: Unsupported HMAC
1664 * Identifier
1665 */
1666 op_err = sctp_get_mbuf_for_msg(sizeof(struct sctp_error_auth_invalid_hmac),
1667 0, M_NOWAIT, 1, MT_HEADER);
1668 if (op_err != NULL) {
1669 /* pre-reserve some space */
1670 SCTP_BUF_RESV_UF(op_err, sizeof(struct sctp_chunkhdr));
1671 /* fill in the error */
1672 cause = mtod(op_err, struct sctp_error_auth_invalid_hmac *);
1673 cause->cause.code = htons(SCTP_CAUSE_UNSUPPORTED_HMACID);
1674 cause->cause.length = htons(sizeof(struct sctp_error_auth_invalid_hmac));
1675 cause->hmac_id = ntohs(hmac_id);
1676 SCTP_BUF_LEN(op_err) = sizeof(struct sctp_error_auth_invalid_hmac);
1677 /* queue it */
1678 sctp_queue_op_err(stcb, op_err);
1679 }
1680 return (-1);
1681 }
1682 /* get the indicated shared key, if available */
1683 if ((stcb->asoc.authinfo.recv_key == NULL) ||
1684 (stcb->asoc.authinfo.recv_keyid != shared_key_id)) {
1685 /* find the shared key on the assoc first */
1686 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys,
1687 shared_key_id);
1688 /* if the shared key isn't found, discard the chunk */
1689 if (skey == NULL) {
1690 SCTP_STAT_INCR(sctps_recvivalkeyid);
1691 SCTPDBG(SCTP_DEBUG_AUTH1,
1692 "SCTP Auth: unknown key id %u\n",
1693 shared_key_id);
1694 return (-1);
1695 }
1696 /* generate a notification if this is a new key id */
1697 if (stcb->asoc.authinfo.recv_keyid != shared_key_id)
1698 /*
1699 * sctp_ulp_notify(SCTP_NOTIFY_AUTH_NEW_KEY, stcb,
1700 * shared_key_id, (void
1701 * *)stcb->asoc.authinfo.recv_keyid);
1702 */
1703 sctp_notify_authentication(stcb, SCTP_AUTH_NEW_KEY,
1704 shared_key_id, stcb->asoc.authinfo.recv_keyid,
1705 SCTP_SO_NOT_LOCKED);
1706 /* compute a new recv assoc key and cache it */
1707 if (stcb->asoc.authinfo.recv_key != NULL)
1708 sctp_free_key(stcb->asoc.authinfo.recv_key);
1709 stcb->asoc.authinfo.recv_key =
1710 sctp_compute_hashkey(stcb->asoc.authinfo.random,
1711 stcb->asoc.authinfo.peer_random, skey->key);
1712 stcb->asoc.authinfo.recv_keyid = shared_key_id;
1713 #ifdef SCTP_DEBUG
1714 if (SCTP_AUTH_DEBUG)
1715 sctp_print_key(stcb->asoc.authinfo.recv_key, "Recv Key");
1716 #endif
1717 }
1718 /* validate the digest length */
1719 digestlen = sctp_get_hmac_digest_len(hmac_id);
1720 if (chunklen < (sizeof(*auth) + digestlen)) {
1721 /* invalid digest length */
1722 SCTP_STAT_INCR(sctps_recvauthfailed);
1723 SCTPDBG(SCTP_DEBUG_AUTH1,
1724 "SCTP Auth: chunk too short for HMAC\n");
1725 return (-1);
1726 }
1727 /* save a copy of the digest, zero the pseudo header, and validate */
1728 memcpy(digest, auth->hmac, digestlen);
1729 sctp_zero_m(m, offset + sizeof(*auth), SCTP_SIZE32(digestlen));
1730 (void)sctp_compute_hmac_m(hmac_id, stcb->asoc.authinfo.recv_key,
1731 m, offset, computed_digest);
1732
1733 /* compare the computed digest with the one in the AUTH chunk */
1734 if (timingsafe_bcmp(digest, computed_digest, digestlen) != 0) {
1735 SCTP_STAT_INCR(sctps_recvauthfailed);
1736 SCTPDBG(SCTP_DEBUG_AUTH1,
1737 "SCTP Auth: HMAC digest check failed\n");
1738 return (-1);
1739 }
1740 return (0);
1741 }
1742
1743 /*
1744 * Generate NOTIFICATION
1745 */
1746 void
1747 sctp_notify_authentication(struct sctp_tcb *stcb, uint32_t indication,
1748 uint16_t keyid, uint16_t alt_keyid, int so_locked)
1749 {
1750 struct mbuf *m_notify;
1751 struct sctp_authkey_event *auth;
1752 struct sctp_queued_to_read *control;
1753
1754 if ((stcb == NULL) ||
1755 (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) ||
1756 (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_ALLGONE) ||
1757 (stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET)
1758 ) {
1759 /* If the socket is gone we are out of here */
1760 return;
1761 }
1762
1763 if (sctp_stcb_is_feature_off(stcb->sctp_ep, stcb, SCTP_PCB_FLAGS_AUTHEVNT))
1764 /* event not enabled */
1765 return;
1766
1767 m_notify = sctp_get_mbuf_for_msg(sizeof(struct sctp_authkey_event),
1768 0, M_NOWAIT, 1, MT_HEADER);
1769 if (m_notify == NULL)
1770 /* no space left */
1771 return;
1772
1773 SCTP_BUF_LEN(m_notify) = 0;
1774 auth = mtod(m_notify, struct sctp_authkey_event *);
1775 memset(auth, 0, sizeof(struct sctp_authkey_event));
1776 auth->auth_type = SCTP_AUTHENTICATION_EVENT;
1777 auth->auth_flags = 0;
1778 auth->auth_length = sizeof(*auth);
1779 auth->auth_keynumber = keyid;
1780 auth->auth_altkeynumber = alt_keyid;
1781 auth->auth_indication = indication;
1782 auth->auth_assoc_id = sctp_get_associd(stcb);
1783
1784 SCTP_BUF_LEN(m_notify) = sizeof(*auth);
1785 SCTP_BUF_NEXT(m_notify) = NULL;
1786
1787 /* append to socket */
1788 control = sctp_build_readq_entry(stcb, stcb->asoc.primary_destination,
1789 0, 0, stcb->asoc.context, 0, 0, 0, m_notify);
1790 if (control == NULL) {
1791 /* no memory */
1792 sctp_m_freem(m_notify);
1793 return;
1794 }
1795 control->length = SCTP_BUF_LEN(m_notify);
1796 control->spec_flags = M_NOTIFICATION;
1797 /* not that we need this */
1798 control->tail_mbuf = m_notify;
1799 sctp_add_to_readq(stcb->sctp_ep, stcb, control,
1800 &stcb->sctp_socket->so_rcv, 1, SCTP_READ_LOCK_NOT_HELD, so_locked);
1801 }
1802
1803
1804 /*-
1805 * validates the AUTHentication related parameters in an INIT/INIT-ACK
1806 * Note: currently only used for INIT as INIT-ACK is handled inline
1807 * with sctp_load_addresses_from_init()
1808 */
1809 int
1810 sctp_validate_init_auth_params(struct mbuf *m, int offset, int limit)
1811 {
1812 struct sctp_paramhdr *phdr, param_buf;
1813 uint16_t ptype, plen;
1814 int peer_supports_asconf = 0;
1815 int peer_supports_auth = 0;
1816 int got_random = 0, got_hmacs = 0, got_chklist = 0;
1817 uint8_t saw_asconf = 0;
1818 uint8_t saw_asconf_ack = 0;
1819
1820 /* go through each of the params. */
1821 phdr = sctp_get_next_param(m, offset, ¶m_buf, sizeof(param_buf));
1822 while (phdr) {
1823 ptype = ntohs(phdr->param_type);
1824 plen = ntohs(phdr->param_length);
1825
1826 if (offset + plen > limit) {
1827 break;
1828 }
1829 if (plen < sizeof(struct sctp_paramhdr)) {
1830 break;
1831 }
1832 if (ptype == SCTP_SUPPORTED_CHUNK_EXT) {
1833 /* A supported extension chunk */
1834 struct sctp_supported_chunk_types_param *pr_supported;
1835 uint8_t local_store[SCTP_SMALL_CHUNK_STORE];
1836 int num_ent, i;
1837
1838 if (plen > sizeof(local_store)) {
1839 break;
1840 }
1841 phdr = sctp_get_next_param(m, offset,
1842 (struct sctp_paramhdr *)&local_store,
1843 plen);
1844 if (phdr == NULL) {
1845 return (-1);
1846 }
1847 pr_supported = (struct sctp_supported_chunk_types_param *)phdr;
1848 num_ent = plen - sizeof(struct sctp_paramhdr);
1849 for (i = 0; i < num_ent; i++) {
1850 switch (pr_supported->chunk_types[i]) {
1851 case SCTP_ASCONF:
1852 case SCTP_ASCONF_ACK:
1853 peer_supports_asconf = 1;
1854 break;
1855 default:
1856 /* one we don't care about */
1857 break;
1858 }
1859 }
1860 } else if (ptype == SCTP_RANDOM) {
1861 /* enforce the random length */
1862 if (plen != (sizeof(struct sctp_auth_random) +
1863 SCTP_AUTH_RANDOM_SIZE_REQUIRED)) {
1864 SCTPDBG(SCTP_DEBUG_AUTH1,
1865 "SCTP: invalid RANDOM len\n");
1866 return (-1);
1867 }
1868 got_random = 1;
1869 } else if (ptype == SCTP_HMAC_LIST) {
1870 struct sctp_auth_hmac_algo *hmacs;
1871 uint8_t store[SCTP_PARAM_BUFFER_SIZE];
1872 int num_hmacs;
1873
1874 if (plen > sizeof(store)) {
1875 break;
1876 }
1877 phdr = sctp_get_next_param(m, offset,
1878 (struct sctp_paramhdr *)store,
1879 plen);
1880 if (phdr == NULL) {
1881 return (-1);
1882 }
1883 hmacs = (struct sctp_auth_hmac_algo *)phdr;
1884 num_hmacs = (plen - sizeof(*hmacs)) / sizeof(hmacs->hmac_ids[0]);
1885 /* validate the hmac list */
1886 if (sctp_verify_hmac_param(hmacs, num_hmacs)) {
1887 SCTPDBG(SCTP_DEBUG_AUTH1,
1888 "SCTP: invalid HMAC param\n");
1889 return (-1);
1890 }
1891 got_hmacs = 1;
1892 } else if (ptype == SCTP_CHUNK_LIST) {
1893 struct sctp_auth_chunk_list *chunks;
1894 uint8_t chunks_store[SCTP_SMALL_CHUNK_STORE];
1895 int i, num_chunks;
1896
1897 if (plen > sizeof(chunks_store)) {
1898 break;
1899 }
1900 phdr = sctp_get_next_param(m, offset,
1901 (struct sctp_paramhdr *)chunks_store,
1902 plen);
1903 if (phdr == NULL) {
1904 return (-1);
1905 }
1906 /*-
1907 * Flip through the list and mark that the
1908 * peer supports asconf/asconf_ack.
1909 */
1910 chunks = (struct sctp_auth_chunk_list *)phdr;
1911 num_chunks = plen - sizeof(*chunks);
1912 for (i = 0; i < num_chunks; i++) {
1913 /* record asconf/asconf-ack if listed */
1914 if (chunks->chunk_types[i] == SCTP_ASCONF)
1915 saw_asconf = 1;
1916 if (chunks->chunk_types[i] == SCTP_ASCONF_ACK)
1917 saw_asconf_ack = 1;
1918
1919 }
1920 if (num_chunks)
1921 got_chklist = 1;
1922 }
1923
1924 offset += SCTP_SIZE32(plen);
1925 if (offset >= limit) {
1926 break;
1927 }
1928 phdr = sctp_get_next_param(m, offset, ¶m_buf,
1929 sizeof(param_buf));
1930 }
1931 /* validate authentication required parameters */
1932 if (got_random && got_hmacs) {
1933 peer_supports_auth = 1;
1934 } else {
1935 peer_supports_auth = 0;
1936 }
1937 if (!peer_supports_auth && got_chklist) {
1938 SCTPDBG(SCTP_DEBUG_AUTH1,
1939 "SCTP: peer sent chunk list w/o AUTH\n");
1940 return (-1);
1941 }
1942 if (peer_supports_asconf && !peer_supports_auth) {
1943 SCTPDBG(SCTP_DEBUG_AUTH1,
1944 "SCTP: peer supports ASCONF but not AUTH\n");
1945 return (-1);
1946 } else if ((peer_supports_asconf) && (peer_supports_auth) &&
1947 ((saw_asconf == 0) || (saw_asconf_ack == 0))) {
1948 return (-2);
1949 }
1950 return (0);
1951 }
1952
1953 void
1954 sctp_initialize_auth_params(struct sctp_inpcb *inp, struct sctp_tcb *stcb)
1955 {
1956 uint16_t chunks_len = 0;
1957 uint16_t hmacs_len = 0;
1958 uint16_t random_len = SCTP_AUTH_RANDOM_SIZE_DEFAULT;
1959 sctp_key_t *new_key;
1960 uint16_t keylen;
1961
1962 /* initialize hmac list from endpoint */
1963 stcb->asoc.local_hmacs = sctp_copy_hmaclist(inp->sctp_ep.local_hmacs);
1964 if (stcb->asoc.local_hmacs != NULL) {
1965 hmacs_len = stcb->asoc.local_hmacs->num_algo *
1966 sizeof(stcb->asoc.local_hmacs->hmac[0]);
1967 }
1968 /* initialize auth chunks list from endpoint */
1969 stcb->asoc.local_auth_chunks =
1970 sctp_copy_chunklist(inp->sctp_ep.local_auth_chunks);
1971 if (stcb->asoc.local_auth_chunks != NULL) {
1972 int i;
1973 for (i = 0; i < 256; i++) {
1974 if (stcb->asoc.local_auth_chunks->chunks[i])
1975 chunks_len++;
1976 }
1977 }
1978 /* copy defaults from the endpoint */
1979 stcb->asoc.authinfo.active_keyid = inp->sctp_ep.default_keyid;
1980
1981 /* copy out the shared key list (by reference) from the endpoint */
1982 (void)sctp_copy_skeylist(&inp->sctp_ep.shared_keys,
1983 &stcb->asoc.shared_keys);
1984
1985 /* now set the concatenated key (random + chunks + hmacs) */
1986 /* key includes parameter headers */
1987 keylen = (3 * sizeof(struct sctp_paramhdr)) + random_len + chunks_len +
1988 hmacs_len;
1989 new_key = sctp_alloc_key(keylen);
1990 if (new_key != NULL) {
1991 struct sctp_paramhdr *ph;
1992 int plen;
1993 /* generate and copy in the RANDOM */
1994 ph = (struct sctp_paramhdr *)new_key->key;
1995 ph->param_type = htons(SCTP_RANDOM);
1996 plen = sizeof(*ph) + random_len;
1997 ph->param_length = htons(plen);
1998 SCTP_READ_RANDOM(new_key->key + sizeof(*ph), random_len);
1999 keylen = plen;
2000
2001 /* append in the AUTH chunks */
2002 /* NOTE: currently we always have chunks to list */
2003 ph = (struct sctp_paramhdr *)(new_key->key + keylen);
2004 ph->param_type = htons(SCTP_CHUNK_LIST);
2005 plen = sizeof(*ph) + chunks_len;
2006 ph->param_length = htons(plen);
2007 keylen += sizeof(*ph);
2008 if (stcb->asoc.local_auth_chunks) {
2009 int i;
2010 for (i = 0; i < 256; i++) {
2011 if (stcb->asoc.local_auth_chunks->chunks[i])
2012 new_key->key[keylen++] = i;
2013 }
2014 }
2015
2016 /* append in the HMACs */
2017 ph = (struct sctp_paramhdr *)(new_key->key + keylen);
2018 ph->param_type = htons(SCTP_HMAC_LIST);
2019 plen = sizeof(*ph) + hmacs_len;
2020 ph->param_length = htons(plen);
2021 keylen += sizeof(*ph);
2022 (void)sctp_serialize_hmaclist(stcb->asoc.local_hmacs,
2023 new_key->key + keylen);
2024 }
2025 if (stcb->asoc.authinfo.random != NULL)
2026 sctp_free_key(stcb->asoc.authinfo.random);
2027 stcb->asoc.authinfo.random = new_key;
2028 stcb->asoc.authinfo.random_len = random_len;
2029 }
2030
2031
2032 #ifdef SCTP_HMAC_TEST
2033 /*
2034 * HMAC and key concatenation tests
2035 */
2036 static void
2037 sctp_print_digest(uint8_t *digest, uint32_t digestlen, const char *str)
2038 {
2039 uint32_t i;
2040
2041 SCTP_PRINTF("\n%s: 0x", str);
2042 if (digest == NULL)
2043 return;
2044
2045 for (i = 0; i < digestlen; i++)
2046 SCTP_PRINTF("%02x", digest[i]);
2047 }
2048
2049 static int
2050 sctp_test_hmac(const char *str, uint16_t hmac_id, uint8_t *key,
2051 uint32_t keylen, uint8_t *text, uint32_t textlen,
2052 uint8_t *digest, uint32_t digestlen)
2053 {
2054 uint8_t computed_digest[SCTP_AUTH_DIGEST_LEN_MAX];
2055
2056 SCTP_PRINTF("\n%s:", str);
2057 sctp_hmac(hmac_id, key, keylen, text, textlen, computed_digest);
2058 sctp_print_digest(digest, digestlen, "Expected digest");
2059 sctp_print_digest(computed_digest, digestlen, "Computed digest");
2060 if (memcmp(digest, computed_digest, digestlen) != 0) {
2061 SCTP_PRINTF("\nFAILED");
2062 return (-1);
2063 } else {
2064 SCTP_PRINTF("\nPASSED");
2065 return (0);
2066 }
2067 }
2068
2069
2070 /*
2071 * RFC 2202: HMAC-SHA1 test cases
2072 */
2073 void
2074 sctp_test_hmac_sha1(void)
2075 {
2076 uint8_t *digest;
2077 uint8_t key[128];
2078 uint32_t keylen;
2079 uint8_t text[128];
2080 uint32_t textlen;
2081 uint32_t digestlen = 20;
2082 int failed = 0;
2083
2084 /*-
2085 * test_case = 1
2086 * key = 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b
2087 * key_len = 20
2088 * data = "Hi There"
2089 * data_len = 8
2090 * digest = 0xb617318655057264e28bc0b6fb378c8ef146be00
2091 */
2092 keylen = 20;
2093 memset(key, 0x0b, keylen);
2094 textlen = 8;
2095 strcpy(text, "Hi There");
2096 digest = "\xb6\x17\x31\x86\x55\x05\x72\x64\xe2\x8b\xc0\xb6\xfb\x37\x8c\x8e\xf1\x46\xbe\x00";
2097 if (sctp_test_hmac("SHA1 test case 1", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2098 text, textlen, digest, digestlen) < 0)
2099 failed++;
2100
2101 /*-
2102 * test_case = 2
2103 * key = "Jefe"
2104 * key_len = 4
2105 * data = "what do ya want for nothing?"
2106 * data_len = 28
2107 * digest = 0xeffcdf6ae5eb2fa2d27416d5f184df9c259a7c79
2108 */
2109 keylen = 4;
2110 strcpy(key, "Jefe");
2111 textlen = 28;
2112 strcpy(text, "what do ya want for nothing?");
2113 digest = "\xef\xfc\xdf\x6a\xe5\xeb\x2f\xa2\xd2\x74\x16\xd5\xf1\x84\xdf\x9c\x25\x9a\x7c\x79";
2114 if (sctp_test_hmac("SHA1 test case 2", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2115 text, textlen, digest, digestlen) < 0)
2116 failed++;
2117
2118 /*-
2119 * test_case = 3
2120 * key = 0xaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
2121 * key_len = 20
2122 * data = 0xdd repeated 50 times
2123 * data_len = 50
2124 * digest = 0x125d7342b9ac11cd91a39af48aa17b4f63f175d3
2125 */
2126 keylen = 20;
2127 memset(key, 0xaa, keylen);
2128 textlen = 50;
2129 memset(text, 0xdd, textlen);
2130 digest = "\x12\x5d\x73\x42\xb9\xac\x11\xcd\x91\xa3\x9a\xf4\x8a\xa1\x7b\x4f\x63\xf1\x75\xd3";
2131 if (sctp_test_hmac("SHA1 test case 3", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2132 text, textlen, digest, digestlen) < 0)
2133 failed++;
2134
2135 /*-
2136 * test_case = 4
2137 * key = 0x0102030405060708090a0b0c0d0e0f10111213141516171819
2138 * key_len = 25
2139 * data = 0xcd repeated 50 times
2140 * data_len = 50
2141 * digest = 0x4c9007f4026250c6bc8414f9bf50c86c2d7235da
2142 */
2143 keylen = 25;
2144 memcpy(key, "\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19", keylen);
2145 textlen = 50;
2146 memset(text, 0xcd, textlen);
2147 digest = "\x4c\x90\x07\xf4\x02\x62\x50\xc6\xbc\x84\x14\xf9\xbf\x50\xc8\x6c\x2d\x72\x35\xda";
2148 if (sctp_test_hmac("SHA1 test case 4", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2149 text, textlen, digest, digestlen) < 0)
2150 failed++;
2151
2152 /*-
2153 * test_case = 5
2154 * key = 0x0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c
2155 * key_len = 20
2156 * data = "Test With Truncation"
2157 * data_len = 20
2158 * digest = 0x4c1a03424b55e07fe7f27be1d58bb9324a9a5a04
2159 * digest-96 = 0x4c1a03424b55e07fe7f27be1
2160 */
2161 keylen = 20;
2162 memset(key, 0x0c, keylen);
2163 textlen = 20;
2164 strcpy(text, "Test With Truncation");
2165 digest = "\x4c\x1a\x03\x42\x4b\x55\xe0\x7f\xe7\xf2\x7b\xe1\xd5\x8b\xb9\x32\x4a\x9a\x5a\x04";
2166 if (sctp_test_hmac("SHA1 test case 5", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2167 text, textlen, digest, digestlen) < 0)
2168 failed++;
2169
2170 /*-
2171 * test_case = 6
2172 * key = 0xaa repeated 80 times
2173 * key_len = 80
2174 * data = "Test Using Larger Than Block-Size Key - Hash Key First"
2175 * data_len = 54
2176 * digest = 0xaa4ae5e15272d00e95705637ce8a3b55ed402112
2177 */
2178 keylen = 80;
2179 memset(key, 0xaa, keylen);
2180 textlen = 54;
2181 strcpy(text, "Test Using Larger Than Block-Size Key - Hash Key First");
2182 digest = "\xaa\x4a\xe5\xe1\x52\x72\xd0\x0e\x95\x70\x56\x37\xce\x8a\x3b\x55\xed\x40\x21\x12";
2183 if (sctp_test_hmac("SHA1 test case 6", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2184 text, textlen, digest, digestlen) < 0)
2185 failed++;
2186
2187 /*-
2188 * test_case = 7
2189 * key = 0xaa repeated 80 times
2190 * key_len = 80
2191 * data = "Test Using Larger Than Block-Size Key and Larger Than One Block-Size Data"
2192 * data_len = 73
2193 * digest = 0xe8e99d0f45237d786d6bbaa7965c7808bbff1a91
2194 */
2195 keylen = 80;
2196 memset(key, 0xaa, keylen);
2197 textlen = 73;
2198 strcpy(text, "Test Using Larger Than Block-Size Key and Larger Than One Block-Size Data");
2199 digest = "\xe8\xe9\x9d\x0f\x45\x23\x7d\x78\x6d\x6b\xba\xa7\x96\x5c\x78\x08\xbb\xff\x1a\x91";
2200 if (sctp_test_hmac("SHA1 test case 7", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2201 text, textlen, digest, digestlen) < 0)
2202 failed++;
2203
2204 /* done with all tests */
2205 if (failed)
2206 SCTP_PRINTF("\nSHA1 test results: %d cases failed", failed);
2207 else
2208 SCTP_PRINTF("\nSHA1 test results: all test cases passed");
2209 }
2210
2211 /*
2212 * test assoc key concatenation
2213 */
2214 static int
2215 sctp_test_key_concatenation(sctp_key_t *key1, sctp_key_t *key2,
2216 sctp_key_t *expected_key)
2217 {
2218 sctp_key_t *key;
2219 int ret_val;
2220
2221 sctp_show_key(key1, "\nkey1");
2222 sctp_show_key(key2, "\nkey2");
2223 key = sctp_compute_hashkey(key1, key2, NULL);
2224 sctp_show_key(expected_key, "\nExpected");
2225 sctp_show_key(key, "\nComputed");
2226 if (memcmp(key, expected_key, expected_key->keylen) != 0) {
2227 SCTP_PRINTF("\nFAILED");
2228 ret_val = -1;
2229 } else {
2230 SCTP_PRINTF("\nPASSED");
2231 ret_val = 0;
2232 }
2233 sctp_free_key(key1);
2234 sctp_free_key(key2);
2235 sctp_free_key(expected_key);
2236 sctp_free_key(key);
2237 return (ret_val);
2238 }
2239
2240
2241 void
2242 sctp_test_authkey(void)
2243 {
2244 sctp_key_t *key1, *key2, *expected_key;
2245 int failed = 0;
2246
2247 /* test case 1 */
2248 key1 = sctp_set_key("\x01\x01\x01\x01", 4);
2249 key2 = sctp_set_key("\x01\x02\x03\x04", 4);
2250 expected_key = sctp_set_key("\x01\x01\x01\x01\x01\x02\x03\x04", 8);
2251 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2252 failed++;
2253
2254 /* test case 2 */
2255 key1 = sctp_set_key("\x00\x00\x00\x01", 4);
2256 key2 = sctp_set_key("\x02", 1);
2257 expected_key = sctp_set_key("\x00\x00\x00\x01\x02", 5);
2258 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2259 failed++;
2260
2261 /* test case 3 */
2262 key1 = sctp_set_key("\x01", 1);
2263 key2 = sctp_set_key("\x00\x00\x00\x02", 4);
2264 expected_key = sctp_set_key("\x01\x00\x00\x00\x02", 5);
2265 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2266 failed++;
2267
2268 /* test case 4 */
2269 key1 = sctp_set_key("\x00\x00\x00\x01", 4);
2270 key2 = sctp_set_key("\x01", 1);
2271 expected_key = sctp_set_key("\x01\x00\x00\x00\x01", 5);
2272 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2273 failed++;
2274
2275 /* test case 5 */
2276 key1 = sctp_set_key("\x01", 1);
2277 key2 = sctp_set_key("\x00\x00\x00\x01", 4);
2278 expected_key = sctp_set_key("\x01\x00\x00\x00\x01", 5);
2279 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2280 failed++;
2281
2282 /* test case 6 */
2283 key1 = sctp_set_key("\x00\x00\x00\x00\x01\x02\x03\x04\x05\x06\x07", 11);
2284 key2 = sctp_set_key("\x00\x00\x00\x00\x01\x02\x03\x04\x05\x06\x08", 11);
2285 expected_key = sctp_set_key("\x00\x00\x00\x00\x01\x02\x03\x04\x05\x06\x07\x00\x00\x00\x00\x01\x02\x03\x04\x05\x06\x08", 22);
2286 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2287 failed++;
2288
2289 /* test case 7 */
2290 key1 = sctp_set_key("\x00\x00\x00\x00\x01\x02\x03\x04\x05\x06\x08", 11);
2291 key2 = sctp_set_key("\x00\x00\x00\x00\x01\x02\x03\x04\x05\x06\x07", 11);
2292 expected_key = sctp_set_key("\x00\x00\x00\x00\x01\x02\x03\x04\x05\x06\x07\x00\x00\x00\x00\x01\x02\x03\x04\x05\x06\x08", 22);
2293 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2294 failed++;
2295
2296 /* done with all tests */
2297 if (failed)
2298 SCTP_PRINTF("\nKey concatenation test results: %d cases failed", failed);
2299 else
2300 SCTP_PRINTF("\nKey concatenation test results: all test cases passed");
2301 }
2302
2303
2304 #if defined(STANDALONE_HMAC_TEST)
2305 int
2306 main(void)
2307 {
2308 sctp_test_hmac_sha1();
2309 sctp_test_authkey();
2310 }
2311
2312 #endif /* STANDALONE_HMAC_TEST */
2313
2314 #endif /* SCTP_HMAC_TEST */
2315