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 #ifdef __FreeBSD__
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD: head/sys/netinet/sctp_auth.c 271673 2014-09-16 14:20:33Z tuexen $");
36 #endif
37
38 #include <netinet/sctp_os.h>
39 #include <netinet/sctp.h>
40 #include <netinet/sctp_header.h>
41 #include <netinet/sctp_pcb.h>
42 #include <netinet/sctp_var.h>
43 #include <netinet/sctp_sysctl.h>
44 #include <netinet/sctputil.h>
45 #include <netinet/sctp_indata.h>
46 #include <netinet/sctp_output.h>
47 #include <netinet/sctp_auth.h>
48
49 #ifdef SCTP_DEBUG
50 #define SCTP_AUTH_DEBUG (SCTP_BASE_SYSCTL(sctp_debug_on) & SCTP_DEBUG_AUTH1)
51 #define SCTP_AUTH_DEBUG2 (SCTP_BASE_SYSCTL(sctp_debug_on) & SCTP_DEBUG_AUTH2)
52 #endif /* SCTP_DEBUG */
53
54
55 void
sctp_clear_chunklist(sctp_auth_chklist_t * chklist)56 sctp_clear_chunklist(sctp_auth_chklist_t *chklist)
57 {
58 bzero(chklist, sizeof(*chklist));
59 /* chklist->num_chunks = 0; */
60 }
61
62 sctp_auth_chklist_t *
sctp_alloc_chunklist(void)63 sctp_alloc_chunklist(void)
64 {
65 sctp_auth_chklist_t *chklist;
66
67 SCTP_MALLOC(chklist, sctp_auth_chklist_t *, sizeof(*chklist),
68 SCTP_M_AUTH_CL);
69 if (chklist == NULL) {
70 SCTPDBG(SCTP_DEBUG_AUTH1, "sctp_alloc_chunklist: failed to get memory!\n");
71 } else {
72 sctp_clear_chunklist(chklist);
73 }
74 return (chklist);
75 }
76
77 void
sctp_free_chunklist(sctp_auth_chklist_t * list)78 sctp_free_chunklist(sctp_auth_chklist_t *list)
79 {
80 if (list != NULL)
81 SCTP_FREE(list, SCTP_M_AUTH_CL);
82 }
83
84 sctp_auth_chklist_t *
sctp_copy_chunklist(sctp_auth_chklist_t * list)85 sctp_copy_chunklist(sctp_auth_chklist_t *list)
86 {
87 sctp_auth_chklist_t *new_list;
88
89 if (list == NULL)
90 return (NULL);
91
92 /* get a new list */
93 new_list = sctp_alloc_chunklist();
94 if (new_list == NULL)
95 return (NULL);
96 /* copy it */
97 bcopy(list, new_list, sizeof(*new_list));
98
99 return (new_list);
100 }
101
102
103 /*
104 * add a chunk to the required chunks list
105 */
106 int
sctp_auth_add_chunk(uint8_t chunk,sctp_auth_chklist_t * list)107 sctp_auth_add_chunk(uint8_t chunk, sctp_auth_chklist_t *list)
108 {
109 if (list == NULL)
110 return (-1);
111
112 /* is chunk restricted? */
113 if ((chunk == SCTP_INITIATION) ||
114 (chunk == SCTP_INITIATION_ACK) ||
115 (chunk == SCTP_SHUTDOWN_COMPLETE) ||
116 (chunk == SCTP_AUTHENTICATION)) {
117 return (-1);
118 }
119 if (list->chunks[chunk] == 0) {
120 list->chunks[chunk] = 1;
121 list->num_chunks++;
122 SCTPDBG(SCTP_DEBUG_AUTH1,
123 "SCTP: added chunk %u (0x%02x) to Auth list\n",
124 chunk, chunk);
125 }
126 return (0);
127 }
128
129 /*
130 * delete a chunk from the required chunks list
131 */
132 int
sctp_auth_delete_chunk(uint8_t chunk,sctp_auth_chklist_t * list)133 sctp_auth_delete_chunk(uint8_t chunk, sctp_auth_chklist_t *list)
134 {
135 if (list == NULL)
136 return (-1);
137
138 if (list->chunks[chunk] == 1) {
139 list->chunks[chunk] = 0;
140 list->num_chunks--;
141 SCTPDBG(SCTP_DEBUG_AUTH1,
142 "SCTP: deleted chunk %u (0x%02x) from Auth list\n",
143 chunk, chunk);
144 }
145 return (0);
146 }
147
148 size_t
sctp_auth_get_chklist_size(const sctp_auth_chklist_t * list)149 sctp_auth_get_chklist_size(const sctp_auth_chklist_t *list)
150 {
151 if (list == NULL)
152 return (0);
153 else
154 return (list->num_chunks);
155 }
156
157 /*
158 * return the current number and list of required chunks caller must
159 * guarantee ptr has space for up to 256 bytes
160 */
161 int
sctp_serialize_auth_chunks(const sctp_auth_chklist_t * list,uint8_t * ptr)162 sctp_serialize_auth_chunks(const sctp_auth_chklist_t *list, uint8_t *ptr)
163 {
164 int i, count = 0;
165
166 if (list == NULL)
167 return (0);
168
169 for (i = 0; i < 256; i++) {
170 if (list->chunks[i] != 0) {
171 *ptr++ = i;
172 count++;
173 }
174 }
175 return (count);
176 }
177
178 int
sctp_pack_auth_chunks(const sctp_auth_chklist_t * list,uint8_t * ptr)179 sctp_pack_auth_chunks(const sctp_auth_chklist_t *list, uint8_t *ptr)
180 {
181 int i, size = 0;
182
183 if (list == NULL)
184 return (0);
185
186 if (list->num_chunks <= 32) {
187 /* just list them, one byte each */
188 for (i = 0; i < 256; i++) {
189 if (list->chunks[i] != 0) {
190 *ptr++ = i;
191 size++;
192 }
193 }
194 } else {
195 int index, offset;
196
197 /* pack into a 32 byte bitfield */
198 for (i = 0; i < 256; i++) {
199 if (list->chunks[i] != 0) {
200 index = i / 8;
201 offset = i % 8;
202 ptr[index] |= (1 << offset);
203 }
204 }
205 size = 32;
206 }
207 return (size);
208 }
209
210 int
sctp_unpack_auth_chunks(const uint8_t * ptr,uint8_t num_chunks,sctp_auth_chklist_t * list)211 sctp_unpack_auth_chunks(const uint8_t *ptr, uint8_t num_chunks,
212 sctp_auth_chklist_t *list)
213 {
214 int i;
215 int size;
216
217 if (list == NULL)
218 return (0);
219
220 if (num_chunks <= 32) {
221 /* just pull them, one byte each */
222 for (i = 0; i < num_chunks; i++) {
223 (void)sctp_auth_add_chunk(*ptr++, list);
224 }
225 size = num_chunks;
226 } else {
227 int index, offset;
228
229 /* unpack from a 32 byte bitfield */
230 for (index = 0; index < 32; index++) {
231 for (offset = 0; offset < 8; offset++) {
232 if (ptr[index] & (1 << offset)) {
233 (void)sctp_auth_add_chunk((index * 8) + offset, list);
234 }
235 }
236 }
237 size = 32;
238 }
239 return (size);
240 }
241
242
243 /*
244 * allocate structure space for a key of length keylen
245 */
246 sctp_key_t *
sctp_alloc_key(uint32_t keylen)247 sctp_alloc_key(uint32_t keylen)
248 {
249 sctp_key_t *new_key;
250
251 SCTP_MALLOC(new_key, sctp_key_t *, sizeof(*new_key) + keylen,
252 SCTP_M_AUTH_KY);
253 if (new_key == NULL) {
254 /* out of memory */
255 return (NULL);
256 }
257 new_key->keylen = keylen;
258 return (new_key);
259 }
260
261 void
sctp_free_key(sctp_key_t * key)262 sctp_free_key(sctp_key_t *key)
263 {
264 if (key != NULL)
265 SCTP_FREE(key,SCTP_M_AUTH_KY);
266 }
267
268 void
sctp_print_key(sctp_key_t * key,const char * str)269 sctp_print_key(sctp_key_t *key, const char *str)
270 {
271 uint32_t i;
272
273 if (key == NULL) {
274 SCTP_PRINTF("%s: [Null key]\n", str);
275 return;
276 }
277 SCTP_PRINTF("%s: len %u, ", str, key->keylen);
278 if (key->keylen) {
279 for (i = 0; i < key->keylen; i++)
280 SCTP_PRINTF("%02x", key->key[i]);
281 SCTP_PRINTF("\n");
282 } else {
283 SCTP_PRINTF("[Null key]\n");
284 }
285 }
286
287 void
sctp_show_key(sctp_key_t * key,const char * str)288 sctp_show_key(sctp_key_t *key, const char *str)
289 {
290 uint32_t i;
291
292 if (key == NULL) {
293 SCTP_PRINTF("%s: [Null key]\n", str);
294 return;
295 }
296 SCTP_PRINTF("%s: len %u, ", str, key->keylen);
297 if (key->keylen) {
298 for (i = 0; i < key->keylen; i++)
299 SCTP_PRINTF("%02x", key->key[i]);
300 SCTP_PRINTF("\n");
301 } else {
302 SCTP_PRINTF("[Null key]\n");
303 }
304 }
305
306 static uint32_t
sctp_get_keylen(sctp_key_t * key)307 sctp_get_keylen(sctp_key_t *key)
308 {
309 if (key != NULL)
310 return (key->keylen);
311 else
312 return (0);
313 }
314
315 /*
316 * generate a new random key of length 'keylen'
317 */
318 sctp_key_t *
sctp_generate_random_key(uint32_t keylen)319 sctp_generate_random_key(uint32_t keylen)
320 {
321 sctp_key_t *new_key;
322
323 new_key = sctp_alloc_key(keylen);
324 if (new_key == NULL) {
325 /* out of memory */
326 return (NULL);
327 }
328 SCTP_READ_RANDOM(new_key->key, keylen);
329 new_key->keylen = keylen;
330 return (new_key);
331 }
332
333 sctp_key_t *
sctp_set_key(uint8_t * key,uint32_t keylen)334 sctp_set_key(uint8_t *key, uint32_t keylen)
335 {
336 sctp_key_t *new_key;
337
338 new_key = sctp_alloc_key(keylen);
339 if (new_key == NULL) {
340 /* out of memory */
341 return (NULL);
342 }
343 bcopy(key, new_key->key, keylen);
344 return (new_key);
345 }
346
347 /*-
348 * given two keys of variable size, compute which key is "larger/smaller"
349 * returns: 1 if key1 > key2
350 * -1 if key1 < key2
351 * 0 if key1 = key2
352 */
353 static int
sctp_compare_key(sctp_key_t * key1,sctp_key_t * key2)354 sctp_compare_key(sctp_key_t *key1, sctp_key_t *key2)
355 {
356 uint32_t maxlen;
357 uint32_t i;
358 uint32_t key1len, key2len;
359 uint8_t *key_1, *key_2;
360 uint8_t val1, val2;
361
362 /* sanity/length check */
363 key1len = sctp_get_keylen(key1);
364 key2len = sctp_get_keylen(key2);
365 if ((key1len == 0) && (key2len == 0))
366 return (0);
367 else if (key1len == 0)
368 return (-1);
369 else if (key2len == 0)
370 return (1);
371
372 if (key1len < key2len) {
373 maxlen = key2len;
374 } else {
375 maxlen = key1len;
376 }
377 key_1 = key1->key;
378 key_2 = key2->key;
379 /* check for numeric equality */
380 for (i = 0; i < maxlen; i++) {
381 /* left-pad with zeros */
382 val1 = (i < (maxlen - key1len)) ? 0 : *(key_1++);
383 val2 = (i < (maxlen - key2len)) ? 0 : *(key_2++);
384 if (val1 > val2) {
385 return (1);
386 } else if (val1 < val2) {
387 return (-1);
388 }
389 }
390 /* keys are equal value, so check lengths */
391 if (key1len == key2len)
392 return (0);
393 else if (key1len < key2len)
394 return (-1);
395 else
396 return (1);
397 }
398
399 /*
400 * generate the concatenated keying material based on the two keys and the
401 * shared key (if available). draft-ietf-tsvwg-auth specifies the specific
402 * order for concatenation
403 */
404 sctp_key_t *
sctp_compute_hashkey(sctp_key_t * key1,sctp_key_t * key2,sctp_key_t * shared)405 sctp_compute_hashkey(sctp_key_t *key1, sctp_key_t *key2, sctp_key_t *shared)
406 {
407 uint32_t keylen;
408 sctp_key_t *new_key;
409 uint8_t *key_ptr;
410
411 keylen = sctp_get_keylen(key1) + sctp_get_keylen(key2) +
412 sctp_get_keylen(shared);
413
414 if (keylen > 0) {
415 /* get space for the new key */
416 new_key = sctp_alloc_key(keylen);
417 if (new_key == NULL) {
418 /* out of memory */
419 return (NULL);
420 }
421 new_key->keylen = keylen;
422 key_ptr = new_key->key;
423 } else {
424 /* all keys empty/null?! */
425 return (NULL);
426 }
427
428 /* concatenate the keys */
429 if (sctp_compare_key(key1, key2) <= 0) {
430 /* key is shared + key1 + key2 */
431 if (sctp_get_keylen(shared)) {
432 bcopy(shared->key, key_ptr, shared->keylen);
433 key_ptr += shared->keylen;
434 }
435 if (sctp_get_keylen(key1)) {
436 bcopy(key1->key, key_ptr, key1->keylen);
437 key_ptr += key1->keylen;
438 }
439 if (sctp_get_keylen(key2)) {
440 bcopy(key2->key, key_ptr, key2->keylen);
441 }
442 } else {
443 /* key is shared + key2 + key1 */
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(key2)) {
449 bcopy(key2->key, key_ptr, key2->keylen);
450 key_ptr += key2->keylen;
451 }
452 if (sctp_get_keylen(key1)) {
453 bcopy(key1->key, key_ptr, key1->keylen);
454 }
455 }
456 return (new_key);
457 }
458
459
460 sctp_sharedkey_t *
sctp_alloc_sharedkey(void)461 sctp_alloc_sharedkey(void)
462 {
463 sctp_sharedkey_t *new_key;
464
465 SCTP_MALLOC(new_key, sctp_sharedkey_t *, sizeof(*new_key),
466 SCTP_M_AUTH_KY);
467 if (new_key == NULL) {
468 /* out of memory */
469 return (NULL);
470 }
471 new_key->keyid = 0;
472 new_key->key = NULL;
473 new_key->refcount = 1;
474 new_key->deactivated = 0;
475 return (new_key);
476 }
477
478 void
sctp_free_sharedkey(sctp_sharedkey_t * skey)479 sctp_free_sharedkey(sctp_sharedkey_t *skey)
480 {
481 if (skey == NULL)
482 return;
483
484 if (SCTP_DECREMENT_AND_CHECK_REFCOUNT(&skey->refcount)) {
485 if (skey->key != NULL)
486 sctp_free_key(skey->key);
487 SCTP_FREE(skey, SCTP_M_AUTH_KY);
488 }
489 }
490
491 sctp_sharedkey_t *
sctp_find_sharedkey(struct sctp_keyhead * shared_keys,uint16_t key_id)492 sctp_find_sharedkey(struct sctp_keyhead *shared_keys, uint16_t key_id)
493 {
494 sctp_sharedkey_t *skey;
495
496 LIST_FOREACH(skey, shared_keys, next) {
497 if (skey->keyid == key_id)
498 return (skey);
499 }
500 return (NULL);
501 }
502
503 int
sctp_insert_sharedkey(struct sctp_keyhead * shared_keys,sctp_sharedkey_t * new_skey)504 sctp_insert_sharedkey(struct sctp_keyhead *shared_keys,
505 sctp_sharedkey_t *new_skey)
506 {
507 sctp_sharedkey_t *skey;
508
509 if ((shared_keys == NULL) || (new_skey == NULL))
510 return (EINVAL);
511
512 /* insert into an empty list? */
513 if (LIST_EMPTY(shared_keys)) {
514 LIST_INSERT_HEAD(shared_keys, new_skey, next);
515 return (0);
516 }
517 /* insert into the existing list, ordered by key id */
518 LIST_FOREACH(skey, shared_keys, next) {
519 if (new_skey->keyid < skey->keyid) {
520 /* insert it before here */
521 LIST_INSERT_BEFORE(skey, new_skey, next);
522 return (0);
523 } else if (new_skey->keyid == skey->keyid) {
524 /* replace the existing key */
525 /* verify this key *can* be replaced */
526 if ((skey->deactivated) && (skey->refcount > 1)) {
527 SCTPDBG(SCTP_DEBUG_AUTH1,
528 "can't replace shared key id %u\n",
529 new_skey->keyid);
530 return (EBUSY);
531 }
532 SCTPDBG(SCTP_DEBUG_AUTH1,
533 "replacing shared key id %u\n",
534 new_skey->keyid);
535 LIST_INSERT_BEFORE(skey, new_skey, next);
536 LIST_REMOVE(skey, next);
537 sctp_free_sharedkey(skey);
538 return (0);
539 }
540 if (LIST_NEXT(skey, next) == NULL) {
541 /* belongs at the end of the list */
542 LIST_INSERT_AFTER(skey, new_skey, next);
543 return (0);
544 }
545 }
546 /* shouldn't reach here */
547 return (0);
548 }
549
550 void
sctp_auth_key_acquire(struct sctp_tcb * stcb,uint16_t key_id)551 sctp_auth_key_acquire(struct sctp_tcb *stcb, uint16_t key_id)
552 {
553 sctp_sharedkey_t *skey;
554
555 /* find the shared key */
556 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, key_id);
557
558 /* bump the ref count */
559 if (skey) {
560 atomic_add_int(&skey->refcount, 1);
561 SCTPDBG(SCTP_DEBUG_AUTH2,
562 "%s: stcb %p key %u refcount acquire to %d\n",
563 __FUNCTION__, (void *)stcb, key_id, skey->refcount);
564 }
565 }
566
567 void
sctp_auth_key_release(struct sctp_tcb * stcb,uint16_t key_id,int so_locked SCTP_UNUSED)568 sctp_auth_key_release(struct sctp_tcb *stcb, uint16_t key_id, int so_locked
569 #if !defined(__APPLE__) && !defined(SCTP_SO_LOCK_TESTING)
570 SCTP_UNUSED
571 #endif
572 )
573 {
574 sctp_sharedkey_t *skey;
575
576 /* find the shared key */
577 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, key_id);
578
579 /* decrement the ref count */
580 if (skey) {
581 sctp_free_sharedkey(skey);
582 SCTPDBG(SCTP_DEBUG_AUTH2,
583 "%s: stcb %p key %u refcount release to %d\n",
584 __FUNCTION__, (void *)stcb, key_id, skey->refcount);
585
586 /* see if a notification should be generated */
587 if ((skey->refcount <= 1) && (skey->deactivated)) {
588 /* notify ULP that key is no longer used */
589 sctp_ulp_notify(SCTP_NOTIFY_AUTH_FREE_KEY, stcb,
590 key_id, 0, so_locked);
591 SCTPDBG(SCTP_DEBUG_AUTH2,
592 "%s: stcb %p key %u no longer used, %d\n",
593 __FUNCTION__, (void *)stcb, key_id, skey->refcount);
594 }
595 }
596 }
597
598 static sctp_sharedkey_t *
sctp_copy_sharedkey(const sctp_sharedkey_t * skey)599 sctp_copy_sharedkey(const sctp_sharedkey_t *skey)
600 {
601 sctp_sharedkey_t *new_skey;
602
603 if (skey == NULL)
604 return (NULL);
605 new_skey = sctp_alloc_sharedkey();
606 if (new_skey == NULL)
607 return (NULL);
608 if (skey->key != NULL)
609 new_skey->key = sctp_set_key(skey->key->key, skey->key->keylen);
610 else
611 new_skey->key = NULL;
612 new_skey->keyid = skey->keyid;
613 return (new_skey);
614 }
615
616 int
sctp_copy_skeylist(const struct sctp_keyhead * src,struct sctp_keyhead * dest)617 sctp_copy_skeylist(const struct sctp_keyhead *src, struct sctp_keyhead *dest)
618 {
619 sctp_sharedkey_t *skey, *new_skey;
620 int count = 0;
621
622 if ((src == NULL) || (dest == NULL))
623 return (0);
624 LIST_FOREACH(skey, src, next) {
625 new_skey = sctp_copy_sharedkey(skey);
626 if (new_skey != NULL) {
627 (void)sctp_insert_sharedkey(dest, new_skey);
628 count++;
629 }
630 }
631 return (count);
632 }
633
634
635 sctp_hmaclist_t *
sctp_alloc_hmaclist(uint16_t num_hmacs)636 sctp_alloc_hmaclist(uint16_t num_hmacs)
637 {
638 sctp_hmaclist_t *new_list;
639 int alloc_size;
640
641 alloc_size = sizeof(*new_list) + num_hmacs * sizeof(new_list->hmac[0]);
642 SCTP_MALLOC(new_list, sctp_hmaclist_t *, alloc_size,
643 SCTP_M_AUTH_HL);
644 if (new_list == NULL) {
645 /* out of memory */
646 return (NULL);
647 }
648 new_list->max_algo = num_hmacs;
649 new_list->num_algo = 0;
650 return (new_list);
651 }
652
653 void
sctp_free_hmaclist(sctp_hmaclist_t * list)654 sctp_free_hmaclist(sctp_hmaclist_t *list)
655 {
656 if (list != NULL) {
657 SCTP_FREE(list,SCTP_M_AUTH_HL);
658 list = NULL;
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 bcopy(&hmac_id, ptr, 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 bzero(new_authinfo, 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 bzero(ipad, blocklen);
978 bzero(opad, blocklen);
979 bcopy(key, ipad, keylen);
980 bcopy(key, opad, 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 bzero(ipad, blocklen);
1038 bzero(opad, blocklen);
1039 bcopy(key, ipad, keylen);
1040 bcopy(key, opad, 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 * verify the HMAC digest using the desired hash key, text, and HMAC
1084 * algorithm.
1085 * Returns -1 on error, 0 on success.
1086 */
1087 int
1088 sctp_verify_hmac(uint16_t hmac_algo, uint8_t *key, uint32_t keylen,
1089 uint8_t *text, uint32_t textlen,
1090 uint8_t *digest, uint32_t digestlen)
1091 {
1092 uint32_t len;
1093 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
1094
1095 /* sanity check the material and length */
1096 if ((key == NULL) || (keylen == 0) ||
1097 (text == NULL) || (textlen == 0) || (digest == NULL)) {
1098 /* can't do HMAC with empty key or text or digest */
1099 return (-1);
1100 }
1101 len = sctp_get_hmac_digest_len(hmac_algo);
1102 if ((len == 0) || (digestlen != len))
1103 return (-1);
1104
1105 /* compute the expected hash */
1106 if (sctp_hmac(hmac_algo, key, keylen, text, textlen, temp) != len)
1107 return (-1);
1108
1109 if (memcmp(digest, temp, digestlen) != 0)
1110 return (-1);
1111 else
1112 return (0);
1113 }
1114
1115
1116 /*
1117 * computes the requested HMAC using a key struct (which may be modified if
1118 * the keylen exceeds the HMAC block len).
1119 */
1120 uint32_t
1121 sctp_compute_hmac(uint16_t hmac_algo, sctp_key_t *key, uint8_t *text,
1122 uint32_t textlen, uint8_t *digest)
1123 {
1124 uint32_t digestlen;
1125 uint32_t blocklen;
1126 sctp_hash_context_t ctx;
1127 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
1128
1129 /* sanity check */
1130 if ((key == NULL) || (text == NULL) || (textlen == 0) ||
1131 (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 bcopy(temp, key->key, key->keylen);
1149 }
1150 return (sctp_hmac(hmac_algo, key->key, key->keylen, text, textlen,
1151 digest));
1152 }
1153
1154 /* mbuf version */
1155 uint32_t
1156 sctp_compute_hmac_m(uint16_t hmac_algo, sctp_key_t *key, struct mbuf *m,
1157 uint32_t m_offset, uint8_t *digest)
1158 {
1159 uint32_t digestlen;
1160 uint32_t blocklen;
1161 sctp_hash_context_t ctx;
1162 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
1163
1164 /* sanity check */
1165 if ((key == NULL) || (m == NULL) || (digest == NULL)) {
1166 /* can't do HMAC with empty key or text or digest store */
1167 return (0);
1168 }
1169 /* validate the hmac algo and get the digest length */
1170 digestlen = sctp_get_hmac_digest_len(hmac_algo);
1171 if (digestlen == 0)
1172 return (0);
1173
1174 /* hash the key if it is longer than the hash block size */
1175 blocklen = sctp_get_hmac_block_len(hmac_algo);
1176 if (key->keylen > blocklen) {
1177 sctp_hmac_init(hmac_algo, &ctx);
1178 sctp_hmac_update(hmac_algo, &ctx, key->key, key->keylen);
1179 sctp_hmac_final(hmac_algo, &ctx, temp);
1180 /* save the hashed key as the new key */
1181 key->keylen = digestlen;
1182 bcopy(temp, key->key, key->keylen);
1183 }
1184 return (sctp_hmac_m(hmac_algo, key->key, key->keylen, m, m_offset, digest, 0));
1185 }
1186
1187 int
1188 sctp_auth_is_supported_hmac(sctp_hmaclist_t *list, uint16_t id)
1189 {
1190 int i;
1191
1192 if ((list == NULL) || (id == SCTP_AUTH_HMAC_ID_RSVD))
1193 return (0);
1194
1195 for (i = 0; i < list->num_algo; i++)
1196 if (list->hmac[i] == id)
1197 return (1);
1198
1199 /* not in the list */
1200 return (0);
1201 }
1202
1203
1204 /*-
1205 * clear any cached key(s) if they match the given key id on an association.
1206 * the cached key(s) will be recomputed and re-cached at next use.
1207 * ASSUMES TCB_LOCK is already held
1208 */
1209 void
1210 sctp_clear_cachedkeys(struct sctp_tcb *stcb, uint16_t keyid)
1211 {
1212 if (stcb == NULL)
1213 return;
1214
1215 if (keyid == stcb->asoc.authinfo.assoc_keyid) {
1216 sctp_free_key(stcb->asoc.authinfo.assoc_key);
1217 stcb->asoc.authinfo.assoc_key = NULL;
1218 }
1219 if (keyid == stcb->asoc.authinfo.recv_keyid) {
1220 sctp_free_key(stcb->asoc.authinfo.recv_key);
1221 stcb->asoc.authinfo.recv_key = NULL;
1222 }
1223 }
1224
1225 /*-
1226 * clear any cached key(s) if they match the given key id for all assocs on
1227 * an endpoint.
1228 * ASSUMES INP_WLOCK is already held
1229 */
1230 void
1231 sctp_clear_cachedkeys_ep(struct sctp_inpcb *inp, uint16_t keyid)
1232 {
1233 struct sctp_tcb *stcb;
1234
1235 if (inp == NULL)
1236 return;
1237
1238 /* clear the cached keys on all assocs on this instance */
1239 LIST_FOREACH(stcb, &inp->sctp_asoc_list, sctp_tcblist) {
1240 SCTP_TCB_LOCK(stcb);
1241 sctp_clear_cachedkeys(stcb, keyid);
1242 SCTP_TCB_UNLOCK(stcb);
1243 }
1244 }
1245
1246 /*-
1247 * delete a shared key from an association
1248 * ASSUMES TCB_LOCK is already held
1249 */
1250 int
1251 sctp_delete_sharedkey(struct sctp_tcb *stcb, uint16_t keyid)
1252 {
1253 sctp_sharedkey_t *skey;
1254
1255 if (stcb == NULL)
1256 return (-1);
1257
1258 /* is the keyid the assoc active sending key */
1259 if (keyid == stcb->asoc.authinfo.active_keyid)
1260 return (-1);
1261
1262 /* does the key exist? */
1263 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
1264 if (skey == NULL)
1265 return (-1);
1266
1267 /* are there other refcount holders on the key? */
1268 if (skey->refcount > 1)
1269 return (-1);
1270
1271 /* remove it */
1272 LIST_REMOVE(skey, next);
1273 sctp_free_sharedkey(skey); /* frees skey->key as well */
1274
1275 /* clear any cached keys */
1276 sctp_clear_cachedkeys(stcb, keyid);
1277 return (0);
1278 }
1279
1280 /*-
1281 * deletes a shared key from the endpoint
1282 * ASSUMES INP_WLOCK is already held
1283 */
1284 int
1285 sctp_delete_sharedkey_ep(struct sctp_inpcb *inp, uint16_t keyid)
1286 {
1287 sctp_sharedkey_t *skey;
1288
1289 if (inp == NULL)
1290 return (-1);
1291
1292 /* is the keyid the active sending key on the endpoint */
1293 if (keyid == inp->sctp_ep.default_keyid)
1294 return (-1);
1295
1296 /* does the key exist? */
1297 skey = sctp_find_sharedkey(&inp->sctp_ep.shared_keys, keyid);
1298 if (skey == NULL)
1299 return (-1);
1300
1301 /* endpoint keys are not refcounted */
1302
1303 /* remove it */
1304 LIST_REMOVE(skey, next);
1305 sctp_free_sharedkey(skey); /* frees skey->key as well */
1306
1307 /* clear any cached keys */
1308 sctp_clear_cachedkeys_ep(inp, keyid);
1309 return (0);
1310 }
1311
1312 /*-
1313 * set the active key on an association
1314 * ASSUMES TCB_LOCK is already held
1315 */
1316 int
1317 sctp_auth_setactivekey(struct sctp_tcb *stcb, uint16_t keyid)
1318 {
1319 sctp_sharedkey_t *skey = NULL;
1320
1321 /* find the key on the assoc */
1322 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
1323 if (skey == NULL) {
1324 /* that key doesn't exist */
1325 return (-1);
1326 }
1327 if ((skey->deactivated) && (skey->refcount > 1)) {
1328 /* can't reactivate a deactivated key with other refcounts */
1329 return (-1);
1330 }
1331
1332 /* set the (new) active key */
1333 stcb->asoc.authinfo.active_keyid = keyid;
1334 /* reset the deactivated flag */
1335 skey->deactivated = 0;
1336
1337 return (0);
1338 }
1339
1340 /*-
1341 * set the active key on an endpoint
1342 * ASSUMES INP_WLOCK is already held
1343 */
1344 int
1345 sctp_auth_setactivekey_ep(struct sctp_inpcb *inp, uint16_t keyid)
1346 {
1347 sctp_sharedkey_t *skey;
1348
1349 /* find the key */
1350 skey = sctp_find_sharedkey(&inp->sctp_ep.shared_keys, keyid);
1351 if (skey == NULL) {
1352 /* that key doesn't exist */
1353 return (-1);
1354 }
1355 inp->sctp_ep.default_keyid = keyid;
1356 return (0);
1357 }
1358
1359 /*-
1360 * deactivates a shared key from the association
1361 * ASSUMES INP_WLOCK is already held
1362 */
1363 int
1364 sctp_deact_sharedkey(struct sctp_tcb *stcb, uint16_t keyid)
1365 {
1366 sctp_sharedkey_t *skey;
1367
1368 if (stcb == NULL)
1369 return (-1);
1370
1371 /* is the keyid the assoc active sending key */
1372 if (keyid == stcb->asoc.authinfo.active_keyid)
1373 return (-1);
1374
1375 /* does the key exist? */
1376 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
1377 if (skey == NULL)
1378 return (-1);
1379
1380 /* are there other refcount holders on the key? */
1381 if (skey->refcount == 1) {
1382 /* no other users, send a notification for this key */
1383 sctp_ulp_notify(SCTP_NOTIFY_AUTH_FREE_KEY, stcb, keyid, 0,
1384 SCTP_SO_LOCKED);
1385 }
1386
1387 /* mark the key as deactivated */
1388 skey->deactivated = 1;
1389
1390 return (0);
1391 }
1392
1393 /*-
1394 * deactivates a shared key from the endpoint
1395 * ASSUMES INP_WLOCK is already held
1396 */
1397 int
1398 sctp_deact_sharedkey_ep(struct sctp_inpcb *inp, uint16_t keyid)
1399 {
1400 sctp_sharedkey_t *skey;
1401
1402 if (inp == NULL)
1403 return (-1);
1404
1405 /* is the keyid the active sending key on the endpoint */
1406 if (keyid == inp->sctp_ep.default_keyid)
1407 return (-1);
1408
1409 /* does the key exist? */
1410 skey = sctp_find_sharedkey(&inp->sctp_ep.shared_keys, keyid);
1411 if (skey == NULL)
1412 return (-1);
1413
1414 /* endpoint keys are not refcounted */
1415
1416 /* remove it */
1417 LIST_REMOVE(skey, next);
1418 sctp_free_sharedkey(skey); /* frees skey->key as well */
1419
1420 return (0);
1421 }
1422
1423 /*
1424 * get local authentication parameters from cookie (from INIT-ACK)
1425 */
1426 void
1427 sctp_auth_get_cookie_params(struct sctp_tcb *stcb, struct mbuf *m,
1428 uint32_t offset, uint32_t length)
1429 {
1430 struct sctp_paramhdr *phdr, tmp_param;
1431 uint16_t plen, ptype;
1432 uint8_t random_store[SCTP_PARAM_BUFFER_SIZE];
1433 struct sctp_auth_random *p_random = NULL;
1434 uint16_t random_len = 0;
1435 uint8_t hmacs_store[SCTP_PARAM_BUFFER_SIZE];
1436 struct sctp_auth_hmac_algo *hmacs = NULL;
1437 uint16_t hmacs_len = 0;
1438 uint8_t chunks_store[SCTP_PARAM_BUFFER_SIZE];
1439 struct sctp_auth_chunk_list *chunks = NULL;
1440 uint16_t num_chunks = 0;
1441 sctp_key_t *new_key;
1442 uint32_t keylen;
1443
1444 /* convert to upper bound */
1445 length += offset;
1446
1447 phdr = (struct sctp_paramhdr *)sctp_m_getptr(m, offset,
1448 sizeof(struct sctp_paramhdr), (uint8_t *)&tmp_param);
1449 while (phdr != NULL) {
1450 ptype = ntohs(phdr->param_type);
1451 plen = ntohs(phdr->param_length);
1452
1453 if ((plen == 0) || (offset + plen > length))
1454 break;
1455
1456 if (ptype == SCTP_RANDOM) {
1457 if (plen > sizeof(random_store))
1458 break;
1459 phdr = sctp_get_next_param(m, offset,
1460 (struct sctp_paramhdr *)random_store, min(plen, sizeof(random_store)));
1461 if (phdr == NULL)
1462 return;
1463 /* save the random and length for the key */
1464 p_random = (struct sctp_auth_random *)phdr;
1465 random_len = plen - sizeof(*p_random);
1466 } else if (ptype == SCTP_HMAC_LIST) {
1467 uint16_t num_hmacs;
1468 uint16_t i;
1469
1470 if (plen > sizeof(hmacs_store))
1471 break;
1472 phdr = sctp_get_next_param(m, offset,
1473 (struct sctp_paramhdr *)hmacs_store, min(plen,sizeof(hmacs_store)));
1474 if (phdr == NULL)
1475 return;
1476 /* save the hmacs list and num for the key */
1477 hmacs = (struct sctp_auth_hmac_algo *)phdr;
1478 hmacs_len = plen - sizeof(*hmacs);
1479 num_hmacs = hmacs_len / sizeof(hmacs->hmac_ids[0]);
1480 if (stcb->asoc.local_hmacs != NULL)
1481 sctp_free_hmaclist(stcb->asoc.local_hmacs);
1482 stcb->asoc.local_hmacs = sctp_alloc_hmaclist(num_hmacs);
1483 if (stcb->asoc.local_hmacs != NULL) {
1484 for (i = 0; i < num_hmacs; i++) {
1485 (void)sctp_auth_add_hmacid(stcb->asoc.local_hmacs,
1486 ntohs(hmacs->hmac_ids[i]));
1487 }
1488 }
1489 } else if (ptype == SCTP_CHUNK_LIST) {
1490 int i;
1491
1492 if (plen > sizeof(chunks_store))
1493 break;
1494 phdr = sctp_get_next_param(m, offset,
1495 (struct sctp_paramhdr *)chunks_store, min(plen,sizeof(chunks_store)));
1496 if (phdr == NULL)
1497 return;
1498 chunks = (struct sctp_auth_chunk_list *)phdr;
1499 num_chunks = plen - sizeof(*chunks);
1500 /* save chunks list and num for the key */
1501 if (stcb->asoc.local_auth_chunks != NULL)
1502 sctp_clear_chunklist(stcb->asoc.local_auth_chunks);
1503 else
1504 stcb->asoc.local_auth_chunks = sctp_alloc_chunklist();
1505 for (i = 0; i < num_chunks; i++) {
1506 (void)sctp_auth_add_chunk(chunks->chunk_types[i],
1507 stcb->asoc.local_auth_chunks);
1508 }
1509 }
1510 /* get next parameter */
1511 offset += SCTP_SIZE32(plen);
1512 if (offset + sizeof(struct sctp_paramhdr) > length)
1513 break;
1514 phdr = (struct sctp_paramhdr *)sctp_m_getptr(m, offset, sizeof(struct sctp_paramhdr),
1515 (uint8_t *)&tmp_param);
1516 }
1517 /* concatenate the full random key */
1518 keylen = sizeof(*p_random) + random_len + sizeof(*hmacs) + hmacs_len;
1519 if (chunks != NULL) {
1520 keylen += sizeof(*chunks) + num_chunks;
1521 }
1522 new_key = sctp_alloc_key(keylen);
1523 if (new_key != NULL) {
1524 /* copy in the RANDOM */
1525 if (p_random != NULL) {
1526 keylen = sizeof(*p_random) + random_len;
1527 bcopy(p_random, new_key->key, keylen);
1528 }
1529 /* append in the AUTH chunks */
1530 if (chunks != NULL) {
1531 bcopy(chunks, new_key->key + keylen,
1532 sizeof(*chunks) + num_chunks);
1533 keylen += sizeof(*chunks) + num_chunks;
1534 }
1535 /* append in the HMACs */
1536 if (hmacs != NULL) {
1537 bcopy(hmacs, new_key->key + keylen,
1538 sizeof(*hmacs) + hmacs_len);
1539 }
1540 }
1541 if (stcb->asoc.authinfo.random != NULL)
1542 sctp_free_key(stcb->asoc.authinfo.random);
1543 stcb->asoc.authinfo.random = new_key;
1544 stcb->asoc.authinfo.random_len = random_len;
1545 sctp_clear_cachedkeys(stcb, stcb->asoc.authinfo.assoc_keyid);
1546 sctp_clear_cachedkeys(stcb, stcb->asoc.authinfo.recv_keyid);
1547
1548 /* negotiate what HMAC to use for the peer */
1549 stcb->asoc.peer_hmac_id = sctp_negotiate_hmacid(stcb->asoc.peer_hmacs,
1550 stcb->asoc.local_hmacs);
1551
1552 /* copy defaults from the endpoint */
1553 /* FIX ME: put in cookie? */
1554 stcb->asoc.authinfo.active_keyid = stcb->sctp_ep->sctp_ep.default_keyid;
1555 /* copy out the shared key list (by reference) from the endpoint */
1556 (void)sctp_copy_skeylist(&stcb->sctp_ep->sctp_ep.shared_keys,
1557 &stcb->asoc.shared_keys);
1558 }
1559
1560 /*
1561 * compute and fill in the HMAC digest for a packet
1562 */
1563 void
1564 sctp_fill_hmac_digest_m(struct mbuf *m, uint32_t auth_offset,
1565 struct sctp_auth_chunk *auth, struct sctp_tcb *stcb, uint16_t keyid)
1566 {
1567 uint32_t digestlen;
1568 sctp_sharedkey_t *skey;
1569 sctp_key_t *key;
1570
1571 if ((stcb == NULL) || (auth == NULL))
1572 return;
1573
1574 /* zero the digest + chunk padding */
1575 digestlen = sctp_get_hmac_digest_len(stcb->asoc.peer_hmac_id);
1576 bzero(auth->hmac, SCTP_SIZE32(digestlen));
1577
1578 /* is the desired key cached? */
1579 if ((keyid != stcb->asoc.authinfo.assoc_keyid) ||
1580 (stcb->asoc.authinfo.assoc_key == NULL)) {
1581 if (stcb->asoc.authinfo.assoc_key != NULL) {
1582 /* free the old cached key */
1583 sctp_free_key(stcb->asoc.authinfo.assoc_key);
1584 }
1585 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
1586 /* the only way skey is NULL is if null key id 0 is used */
1587 if (skey != NULL)
1588 key = skey->key;
1589 else
1590 key = NULL;
1591 /* compute a new assoc key and cache it */
1592 stcb->asoc.authinfo.assoc_key =
1593 sctp_compute_hashkey(stcb->asoc.authinfo.random,
1594 stcb->asoc.authinfo.peer_random, key);
1595 stcb->asoc.authinfo.assoc_keyid = keyid;
1596 SCTPDBG(SCTP_DEBUG_AUTH1, "caching key id %u\n",
1597 stcb->asoc.authinfo.assoc_keyid);
1598 #ifdef SCTP_DEBUG
1599 if (SCTP_AUTH_DEBUG)
1600 sctp_print_key(stcb->asoc.authinfo.assoc_key,
1601 "Assoc Key");
1602 #endif
1603 }
1604
1605 /* set in the active key id */
1606 auth->shared_key_id = htons(keyid);
1607
1608 /* compute and fill in the digest */
1609 (void)sctp_compute_hmac_m(stcb->asoc.peer_hmac_id, stcb->asoc.authinfo.assoc_key,
1610 m, auth_offset, auth->hmac);
1611 }
1612
1613
1614 static void
1615 sctp_bzero_m(struct mbuf *m, uint32_t m_offset, uint32_t size)
1616 {
1617 struct mbuf *m_tmp;
1618 uint8_t *data;
1619
1620 /* sanity check */
1621 if (m == NULL)
1622 return;
1623
1624 /* find the correct starting mbuf and offset (get start position) */
1625 m_tmp = m;
1626 while ((m_tmp != NULL) && (m_offset >= (uint32_t) SCTP_BUF_LEN(m_tmp))) {
1627 m_offset -= SCTP_BUF_LEN(m_tmp);
1628 m_tmp = SCTP_BUF_NEXT(m_tmp);
1629 }
1630 /* now use the rest of the mbuf chain */
1631 while ((m_tmp != NULL) && (size > 0)) {
1632 data = mtod(m_tmp, uint8_t *) + m_offset;
1633 if (size > (uint32_t) SCTP_BUF_LEN(m_tmp)) {
1634 bzero(data, SCTP_BUF_LEN(m_tmp));
1635 size -= SCTP_BUF_LEN(m_tmp);
1636 } else {
1637 bzero(data, size);
1638 size = 0;
1639 }
1640 /* clear the offset since it's only for the first mbuf */
1641 m_offset = 0;
1642 m_tmp = SCTP_BUF_NEXT(m_tmp);
1643 }
1644 }
1645
1646 /*-
1647 * process the incoming Authentication chunk
1648 * return codes:
1649 * -1 on any authentication error
1650 * 0 on authentication verification
1651 */
1652 int
1653 sctp_handle_auth(struct sctp_tcb *stcb, struct sctp_auth_chunk *auth,
1654 struct mbuf *m, uint32_t offset)
1655 {
1656 uint16_t chunklen;
1657 uint16_t shared_key_id;
1658 uint16_t hmac_id;
1659 sctp_sharedkey_t *skey;
1660 uint32_t digestlen;
1661 uint8_t digest[SCTP_AUTH_DIGEST_LEN_MAX];
1662 uint8_t computed_digest[SCTP_AUTH_DIGEST_LEN_MAX];
1663
1664 /* auth is checked for NULL by caller */
1665 chunklen = ntohs(auth->ch.chunk_length);
1666 if (chunklen < sizeof(*auth)) {
1667 SCTP_STAT_INCR(sctps_recvauthfailed);
1668 return (-1);
1669 }
1670 SCTP_STAT_INCR(sctps_recvauth);
1671
1672 /* get the auth params */
1673 shared_key_id = ntohs(auth->shared_key_id);
1674 hmac_id = ntohs(auth->hmac_id);
1675 SCTPDBG(SCTP_DEBUG_AUTH1,
1676 "SCTP AUTH Chunk: shared key %u, HMAC id %u\n",
1677 shared_key_id, hmac_id);
1678
1679 /* is the indicated HMAC supported? */
1680 if (!sctp_auth_is_supported_hmac(stcb->asoc.local_hmacs, hmac_id)) {
1681 struct mbuf *m_err;
1682 struct sctp_auth_invalid_hmac *err;
1683
1684 SCTP_STAT_INCR(sctps_recvivalhmacid);
1685 SCTPDBG(SCTP_DEBUG_AUTH1,
1686 "SCTP Auth: unsupported HMAC id %u\n",
1687 hmac_id);
1688 /*
1689 * report this in an Error Chunk: Unsupported HMAC
1690 * Identifier
1691 */
1692 m_err = sctp_get_mbuf_for_msg(sizeof(*err), 0, M_NOWAIT,
1693 1, MT_HEADER);
1694 if (m_err != NULL) {
1695 /* pre-reserve some space */
1696 SCTP_BUF_RESV_UF(m_err, sizeof(struct sctp_chunkhdr));
1697 /* fill in the error */
1698 err = mtod(m_err, struct sctp_auth_invalid_hmac *);
1699 bzero(err, sizeof(*err));
1700 err->ph.param_type = htons(SCTP_CAUSE_UNSUPPORTED_HMACID);
1701 err->ph.param_length = htons(sizeof(*err));
1702 err->hmac_id = ntohs(hmac_id);
1703 SCTP_BUF_LEN(m_err) = sizeof(*err);
1704 /* queue it */
1705 sctp_queue_op_err(stcb, m_err);
1706 }
1707 return (-1);
1708 }
1709 /* get the indicated shared key, if available */
1710 if ((stcb->asoc.authinfo.recv_key == NULL) ||
1711 (stcb->asoc.authinfo.recv_keyid != shared_key_id)) {
1712 /* find the shared key on the assoc first */
1713 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys,
1714 shared_key_id);
1715 /* if the shared key isn't found, discard the chunk */
1716 if (skey == NULL) {
1717 SCTP_STAT_INCR(sctps_recvivalkeyid);
1718 SCTPDBG(SCTP_DEBUG_AUTH1,
1719 "SCTP Auth: unknown key id %u\n",
1720 shared_key_id);
1721 return (-1);
1722 }
1723 /* generate a notification if this is a new key id */
1724 if (stcb->asoc.authinfo.recv_keyid != shared_key_id)
1725 /*
1726 * sctp_ulp_notify(SCTP_NOTIFY_AUTH_NEW_KEY, stcb,
1727 * shared_key_id, (void
1728 * *)stcb->asoc.authinfo.recv_keyid);
1729 */
1730 sctp_notify_authentication(stcb, SCTP_AUTH_NEW_KEY,
1731 shared_key_id, stcb->asoc.authinfo.recv_keyid,
1732 SCTP_SO_NOT_LOCKED);
1733 /* compute a new recv assoc key and cache it */
1734 if (stcb->asoc.authinfo.recv_key != NULL)
1735 sctp_free_key(stcb->asoc.authinfo.recv_key);
1736 stcb->asoc.authinfo.recv_key =
1737 sctp_compute_hashkey(stcb->asoc.authinfo.random,
1738 stcb->asoc.authinfo.peer_random, skey->key);
1739 stcb->asoc.authinfo.recv_keyid = shared_key_id;
1740 #ifdef SCTP_DEBUG
1741 if (SCTP_AUTH_DEBUG)
1742 sctp_print_key(stcb->asoc.authinfo.recv_key, "Recv Key");
1743 #endif
1744 }
1745 /* validate the digest length */
1746 digestlen = sctp_get_hmac_digest_len(hmac_id);
1747 if (chunklen < (sizeof(*auth) + digestlen)) {
1748 /* invalid digest length */
1749 SCTP_STAT_INCR(sctps_recvauthfailed);
1750 SCTPDBG(SCTP_DEBUG_AUTH1,
1751 "SCTP Auth: chunk too short for HMAC\n");
1752 return (-1);
1753 }
1754 /* save a copy of the digest, zero the pseudo header, and validate */
1755 bcopy(auth->hmac, digest, digestlen);
1756 sctp_bzero_m(m, offset + sizeof(*auth), SCTP_SIZE32(digestlen));
1757 (void)sctp_compute_hmac_m(hmac_id, stcb->asoc.authinfo.recv_key,
1758 m, offset, computed_digest);
1759
1760 /* compare the computed digest with the one in the AUTH chunk */
1761 if (memcmp(digest, computed_digest, digestlen) != 0) {
1762 SCTP_STAT_INCR(sctps_recvauthfailed);
1763 SCTPDBG(SCTP_DEBUG_AUTH1,
1764 "SCTP Auth: HMAC digest check failed\n");
1765 return (-1);
1766 }
1767 return (0);
1768 }
1769
1770 /*
1771 * Generate NOTIFICATION
1772 */
1773 void
1774 sctp_notify_authentication(struct sctp_tcb *stcb, uint32_t indication,
1775 uint16_t keyid, uint16_t alt_keyid, int so_locked
1776 #if !defined(__APPLE__) && !defined(SCTP_SO_LOCK_TESTING)
1777 SCTP_UNUSED
1778 #endif
1779 )
1780 {
1781 struct mbuf *m_notify;
1782 struct sctp_authkey_event *auth;
1783 struct sctp_queued_to_read *control;
1784
1785 if ((stcb == NULL) ||
1786 (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) ||
1787 (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_ALLGONE) ||
1788 (stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET)
1789 ) {
1790 /* If the socket is gone we are out of here */
1791 return;
1792 }
1793
1794 if (sctp_stcb_is_feature_off(stcb->sctp_ep, stcb, SCTP_PCB_FLAGS_AUTHEVNT))
1795 /* event not enabled */
1796 return;
1797
1798 m_notify = sctp_get_mbuf_for_msg(sizeof(struct sctp_authkey_event),
1799 0, M_NOWAIT, 1, MT_HEADER);
1800 if (m_notify == NULL)
1801 /* no space left */
1802 return;
1803
1804 SCTP_BUF_LEN(m_notify) = 0;
1805 auth = mtod(m_notify, struct sctp_authkey_event *);
1806 memset(auth, 0, sizeof(struct sctp_authkey_event));
1807 auth->auth_type = SCTP_AUTHENTICATION_EVENT;
1808 auth->auth_flags = 0;
1809 auth->auth_length = sizeof(*auth);
1810 auth->auth_keynumber = keyid;
1811 auth->auth_altkeynumber = alt_keyid;
1812 auth->auth_indication = indication;
1813 auth->auth_assoc_id = sctp_get_associd(stcb);
1814
1815 SCTP_BUF_LEN(m_notify) = sizeof(*auth);
1816 SCTP_BUF_NEXT(m_notify) = NULL;
1817
1818 /* append to socket */
1819 control = sctp_build_readq_entry(stcb, stcb->asoc.primary_destination,
1820 0, 0, stcb->asoc.context, 0, 0, 0, m_notify);
1821 if (control == NULL) {
1822 /* no memory */
1823 sctp_m_freem(m_notify);
1824 return;
1825 }
1826 control->spec_flags = M_NOTIFICATION;
1827 control->length = SCTP_BUF_LEN(m_notify);
1828 /* not that we need this */
1829 control->tail_mbuf = m_notify;
1830 sctp_add_to_readq(stcb->sctp_ep, stcb, control,
1831 &stcb->sctp_socket->so_rcv, 1, SCTP_READ_LOCK_NOT_HELD, so_locked);
1832 }
1833
1834
1835 /*-
1836 * validates the AUTHentication related parameters in an INIT/INIT-ACK
1837 * Note: currently only used for INIT as INIT-ACK is handled inline
1838 * with sctp_load_addresses_from_init()
1839 */
1840 int
1841 sctp_validate_init_auth_params(struct mbuf *m, int offset, int limit)
1842 {
1843 struct sctp_paramhdr *phdr, parm_buf;
1844 uint16_t ptype, plen;
1845 int peer_supports_asconf = 0;
1846 int peer_supports_auth = 0;
1847 int got_random = 0, got_hmacs = 0, got_chklist = 0;
1848 uint8_t saw_asconf = 0;
1849 uint8_t saw_asconf_ack = 0;
1850
1851 /* go through each of the params. */
1852 phdr = sctp_get_next_param(m, offset, &parm_buf, sizeof(parm_buf));
1853 while (phdr) {
1854 ptype = ntohs(phdr->param_type);
1855 plen = ntohs(phdr->param_length);
1856
1857 if (offset + plen > limit) {
1858 break;
1859 }
1860 if (plen < sizeof(struct sctp_paramhdr)) {
1861 break;
1862 }
1863 if (ptype == SCTP_SUPPORTED_CHUNK_EXT) {
1864 /* A supported extension chunk */
1865 struct sctp_supported_chunk_types_param *pr_supported;
1866 uint8_t local_store[SCTP_PARAM_BUFFER_SIZE];
1867 int num_ent, i;
1868
1869 phdr = sctp_get_next_param(m, offset,
1870 (struct sctp_paramhdr *)&local_store, min(plen,sizeof(local_store)));
1871 if (phdr == NULL) {
1872 return (-1);
1873 }
1874 pr_supported = (struct sctp_supported_chunk_types_param *)phdr;
1875 num_ent = plen - sizeof(struct sctp_paramhdr);
1876 for (i = 0; i < num_ent; i++) {
1877 switch (pr_supported->chunk_types[i]) {
1878 case SCTP_ASCONF:
1879 case SCTP_ASCONF_ACK:
1880 peer_supports_asconf = 1;
1881 break;
1882 default:
1883 /* one we don't care about */
1884 break;
1885 }
1886 }
1887 } else if (ptype == SCTP_RANDOM) {
1888 got_random = 1;
1889 /* enforce the random length */
1890 if (plen != (sizeof(struct sctp_auth_random) +
1891 SCTP_AUTH_RANDOM_SIZE_REQUIRED)) {
1892 SCTPDBG(SCTP_DEBUG_AUTH1,
1893 "SCTP: invalid RANDOM len\n");
1894 return (-1);
1895 }
1896 } else if (ptype == SCTP_HMAC_LIST) {
1897 uint8_t store[SCTP_PARAM_BUFFER_SIZE];
1898 struct sctp_auth_hmac_algo *hmacs;
1899 int num_hmacs;
1900
1901 if (plen > sizeof(store))
1902 break;
1903 phdr = sctp_get_next_param(m, offset,
1904 (struct sctp_paramhdr *)store, min(plen,sizeof(store)));
1905 if (phdr == NULL)
1906 return (-1);
1907 hmacs = (struct sctp_auth_hmac_algo *)phdr;
1908 num_hmacs = (plen - sizeof(*hmacs)) /
1909 sizeof(hmacs->hmac_ids[0]);
1910 /* validate the hmac list */
1911 if (sctp_verify_hmac_param(hmacs, num_hmacs)) {
1912 SCTPDBG(SCTP_DEBUG_AUTH1,
1913 "SCTP: invalid HMAC param\n");
1914 return (-1);
1915 }
1916 got_hmacs = 1;
1917 } else if (ptype == SCTP_CHUNK_LIST) {
1918 int i, num_chunks;
1919 uint8_t chunks_store[SCTP_SMALL_CHUNK_STORE];
1920 /* did the peer send a non-empty chunk list? */
1921 struct sctp_auth_chunk_list *chunks = NULL;
1922 phdr = sctp_get_next_param(m, offset,
1923 (struct sctp_paramhdr *)chunks_store,
1924 min(plen,sizeof(chunks_store)));
1925 if (phdr == NULL)
1926 return (-1);
1927
1928 /*-
1929 * Flip through the list and mark that the
1930 * peer supports asconf/asconf_ack.
1931 */
1932 chunks = (struct sctp_auth_chunk_list *)phdr;
1933 num_chunks = plen - sizeof(*chunks);
1934 for (i = 0; i < num_chunks; i++) {
1935 /* record asconf/asconf-ack if listed */
1936 if (chunks->chunk_types[i] == SCTP_ASCONF)
1937 saw_asconf = 1;
1938 if (chunks->chunk_types[i] == SCTP_ASCONF_ACK)
1939 saw_asconf_ack = 1;
1940
1941 }
1942 if (num_chunks)
1943 got_chklist = 1;
1944 }
1945
1946 offset += SCTP_SIZE32(plen);
1947 if (offset >= limit) {
1948 break;
1949 }
1950 phdr = sctp_get_next_param(m, offset, &parm_buf,
1951 sizeof(parm_buf));
1952 }
1953 /* validate authentication required parameters */
1954 if (got_random && got_hmacs) {
1955 peer_supports_auth = 1;
1956 } else {
1957 peer_supports_auth = 0;
1958 }
1959 if (!peer_supports_auth && got_chklist) {
1960 SCTPDBG(SCTP_DEBUG_AUTH1,
1961 "SCTP: peer sent chunk list w/o AUTH\n");
1962 return (-1);
1963 }
1964 if (peer_supports_asconf && !peer_supports_auth) {
1965 SCTPDBG(SCTP_DEBUG_AUTH1,
1966 "SCTP: peer supports ASCONF but not AUTH\n");
1967 return (-1);
1968 } else if ((peer_supports_asconf) && (peer_supports_auth) &&
1969 ((saw_asconf == 0) || (saw_asconf_ack == 0))) {
1970 return (-2);
1971 }
1972 return (0);
1973 }
1974
1975 void
1976 sctp_initialize_auth_params(struct sctp_inpcb *inp, struct sctp_tcb *stcb)
1977 {
1978 uint16_t chunks_len = 0;
1979 uint16_t hmacs_len = 0;
1980 uint16_t random_len = SCTP_AUTH_RANDOM_SIZE_DEFAULT;
1981 sctp_key_t *new_key;
1982 uint16_t keylen;
1983
1984 /* initialize hmac list from endpoint */
1985 stcb->asoc.local_hmacs = sctp_copy_hmaclist(inp->sctp_ep.local_hmacs);
1986 if (stcb->asoc.local_hmacs != NULL) {
1987 hmacs_len = stcb->asoc.local_hmacs->num_algo *
1988 sizeof(stcb->asoc.local_hmacs->hmac[0]);
1989 }
1990 /* initialize auth chunks list from endpoint */
1991 stcb->asoc.local_auth_chunks =
1992 sctp_copy_chunklist(inp->sctp_ep.local_auth_chunks);
1993 if (stcb->asoc.local_auth_chunks != NULL) {
1994 int i;
1995 for (i = 0; i < 256; i++) {
1996 if (stcb->asoc.local_auth_chunks->chunks[i])
1997 chunks_len++;
1998 }
1999 }
2000 /* copy defaults from the endpoint */
2001 stcb->asoc.authinfo.active_keyid = inp->sctp_ep.default_keyid;
2002
2003 /* copy out the shared key list (by reference) from the endpoint */
2004 (void)sctp_copy_skeylist(&inp->sctp_ep.shared_keys,
2005 &stcb->asoc.shared_keys);
2006
2007 /* now set the concatenated key (random + chunks + hmacs) */
2008 /* key includes parameter headers */
2009 keylen = (3 * sizeof(struct sctp_paramhdr)) + random_len + chunks_len +
2010 hmacs_len;
2011 new_key = sctp_alloc_key(keylen);
2012 if (new_key != NULL) {
2013 struct sctp_paramhdr *ph;
2014 int plen;
2015 /* generate and copy in the RANDOM */
2016 ph = (struct sctp_paramhdr *)new_key->key;
2017 ph->param_type = htons(SCTP_RANDOM);
2018 plen = sizeof(*ph) + random_len;
2019 ph->param_length = htons(plen);
2020 SCTP_READ_RANDOM(new_key->key + sizeof(*ph), random_len);
2021 keylen = plen;
2022
2023 /* append in the AUTH chunks */
2024 /* NOTE: currently we always have chunks to list */
2025 ph = (struct sctp_paramhdr *)(new_key->key + keylen);
2026 ph->param_type = htons(SCTP_CHUNK_LIST);
2027 plen = sizeof(*ph) + chunks_len;
2028 ph->param_length = htons(plen);
2029 keylen += sizeof(*ph);
2030 if (stcb->asoc.local_auth_chunks) {
2031 int i;
2032 for (i = 0; i < 256; i++) {
2033 if (stcb->asoc.local_auth_chunks->chunks[i])
2034 new_key->key[keylen++] = i;
2035 }
2036 }
2037
2038 /* append in the HMACs */
2039 ph = (struct sctp_paramhdr *)(new_key->key + keylen);
2040 ph->param_type = htons(SCTP_HMAC_LIST);
2041 plen = sizeof(*ph) + hmacs_len;
2042 ph->param_length = htons(plen);
2043 keylen += sizeof(*ph);
2044 (void)sctp_serialize_hmaclist(stcb->asoc.local_hmacs,
2045 new_key->key + keylen);
2046 }
2047 if (stcb->asoc.authinfo.random != NULL)
2048 sctp_free_key(stcb->asoc.authinfo.random);
2049 stcb->asoc.authinfo.random = new_key;
2050 stcb->asoc.authinfo.random_len = random_len;
2051 }
2052
2053
2054 #ifdef SCTP_HMAC_TEST
2055 /*
2056 * HMAC and key concatenation tests
2057 */
2058 static void
2059 sctp_print_digest(uint8_t *digest, uint32_t digestlen, const char *str)
2060 {
2061 uint32_t i;
2062
2063 SCTP_PRINTF("\n%s: 0x", str);
2064 if (digest == NULL)
2065 return;
2066
2067 for (i = 0; i < digestlen; i++)
2068 SCTP_PRINTF("%02x", digest[i]);
2069 }
2070
2071 static int
2072 sctp_test_hmac(const char *str, uint16_t hmac_id, uint8_t *key,
2073 uint32_t keylen, uint8_t *text, uint32_t textlen,
2074 uint8_t *digest, uint32_t digestlen)
2075 {
2076 uint8_t computed_digest[SCTP_AUTH_DIGEST_LEN_MAX];
2077
2078 SCTP_PRINTF("\n%s:", str);
2079 sctp_hmac(hmac_id, key, keylen, text, textlen, computed_digest);
2080 sctp_print_digest(digest, digestlen, "Expected digest");
2081 sctp_print_digest(computed_digest, digestlen, "Computed digest");
2082 if (memcmp(digest, computed_digest, digestlen) != 0) {
2083 SCTP_PRINTF("\nFAILED");
2084 return (-1);
2085 } else {
2086 SCTP_PRINTF("\nPASSED");
2087 return (0);
2088 }
2089 }
2090
2091
2092 /*
2093 * RFC 2202: HMAC-SHA1 test cases
2094 */
2095 void
2096 sctp_test_hmac_sha1(void)
2097 {
2098 uint8_t *digest;
2099 uint8_t key[128];
2100 uint32_t keylen;
2101 uint8_t text[128];
2102 uint32_t textlen;
2103 uint32_t digestlen = 20;
2104 int failed = 0;
2105
2106 /*-
2107 * test_case = 1
2108 * key = 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b
2109 * key_len = 20
2110 * data = "Hi There"
2111 * data_len = 8
2112 * digest = 0xb617318655057264e28bc0b6fb378c8ef146be00
2113 */
2114 keylen = 20;
2115 memset(key, 0x0b, keylen);
2116 textlen = 8;
2117 strcpy(text, "Hi There");
2118 digest = "\xb6\x17\x31\x86\x55\x05\x72\x64\xe2\x8b\xc0\xb6\xfb\x37\x8c\x8e\xf1\x46\xbe\x00";
2119 if (sctp_test_hmac("SHA1 test case 1", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2120 text, textlen, digest, digestlen) < 0)
2121 failed++;
2122
2123 /*-
2124 * test_case = 2
2125 * key = "Jefe"
2126 * key_len = 4
2127 * data = "what do ya want for nothing?"
2128 * data_len = 28
2129 * digest = 0xeffcdf6ae5eb2fa2d27416d5f184df9c259a7c79
2130 */
2131 keylen = 4;
2132 strcpy(key, "Jefe");
2133 textlen = 28;
2134 strcpy(text, "what do ya want for nothing?");
2135 digest = "\xef\xfc\xdf\x6a\xe5\xeb\x2f\xa2\xd2\x74\x16\xd5\xf1\x84\xdf\x9c\x25\x9a\x7c\x79";
2136 if (sctp_test_hmac("SHA1 test case 2", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2137 text, textlen, digest, digestlen) < 0)
2138 failed++;
2139
2140 /*-
2141 * test_case = 3
2142 * key = 0xaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
2143 * key_len = 20
2144 * data = 0xdd repeated 50 times
2145 * data_len = 50
2146 * digest = 0x125d7342b9ac11cd91a39af48aa17b4f63f175d3
2147 */
2148 keylen = 20;
2149 memset(key, 0xaa, keylen);
2150 textlen = 50;
2151 memset(text, 0xdd, textlen);
2152 digest = "\x12\x5d\x73\x42\xb9\xac\x11\xcd\x91\xa3\x9a\xf4\x8a\xa1\x7b\x4f\x63\xf1\x75\xd3";
2153 if (sctp_test_hmac("SHA1 test case 3", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2154 text, textlen, digest, digestlen) < 0)
2155 failed++;
2156
2157 /*-
2158 * test_case = 4
2159 * key = 0x0102030405060708090a0b0c0d0e0f10111213141516171819
2160 * key_len = 25
2161 * data = 0xcd repeated 50 times
2162 * data_len = 50
2163 * digest = 0x4c9007f4026250c6bc8414f9bf50c86c2d7235da
2164 */
2165 keylen = 25;
2166 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);
2167 textlen = 50;
2168 memset(text, 0xcd, textlen);
2169 digest = "\x4c\x90\x07\xf4\x02\x62\x50\xc6\xbc\x84\x14\xf9\xbf\x50\xc8\x6c\x2d\x72\x35\xda";
2170 if (sctp_test_hmac("SHA1 test case 4", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2171 text, textlen, digest, digestlen) < 0)
2172 failed++;
2173
2174 /*-
2175 * test_case = 5
2176 * key = 0x0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c
2177 * key_len = 20
2178 * data = "Test With Truncation"
2179 * data_len = 20
2180 * digest = 0x4c1a03424b55e07fe7f27be1d58bb9324a9a5a04
2181 * digest-96 = 0x4c1a03424b55e07fe7f27be1
2182 */
2183 keylen = 20;
2184 memset(key, 0x0c, keylen);
2185 textlen = 20;
2186 strcpy(text, "Test With Truncation");
2187 digest = "\x4c\x1a\x03\x42\x4b\x55\xe0\x7f\xe7\xf2\x7b\xe1\xd5\x8b\xb9\x32\x4a\x9a\x5a\x04";
2188 if (sctp_test_hmac("SHA1 test case 5", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2189 text, textlen, digest, digestlen) < 0)
2190 failed++;
2191
2192 /*-
2193 * test_case = 6
2194 * key = 0xaa repeated 80 times
2195 * key_len = 80
2196 * data = "Test Using Larger Than Block-Size Key - Hash Key First"
2197 * data_len = 54
2198 * digest = 0xaa4ae5e15272d00e95705637ce8a3b55ed402112
2199 */
2200 keylen = 80;
2201 memset(key, 0xaa, keylen);
2202 textlen = 54;
2203 strcpy(text, "Test Using Larger Than Block-Size Key - Hash Key First");
2204 digest = "\xaa\x4a\xe5\xe1\x52\x72\xd0\x0e\x95\x70\x56\x37\xce\x8a\x3b\x55\xed\x40\x21\x12";
2205 if (sctp_test_hmac("SHA1 test case 6", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2206 text, textlen, digest, digestlen) < 0)
2207 failed++;
2208
2209 /*-
2210 * test_case = 7
2211 * key = 0xaa repeated 80 times
2212 * key_len = 80
2213 * data = "Test Using Larger Than Block-Size Key and Larger Than One Block-Size Data"
2214 * data_len = 73
2215 * digest = 0xe8e99d0f45237d786d6bbaa7965c7808bbff1a91
2216 */
2217 keylen = 80;
2218 memset(key, 0xaa, keylen);
2219 textlen = 73;
2220 strcpy(text, "Test Using Larger Than Block-Size Key and Larger Than One Block-Size Data");
2221 digest = "\xe8\xe9\x9d\x0f\x45\x23\x7d\x78\x6d\x6b\xba\xa7\x96\x5c\x78\x08\xbb\xff\x1a\x91";
2222 if (sctp_test_hmac("SHA1 test case 7", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2223 text, textlen, digest, digestlen) < 0)
2224 failed++;
2225
2226 /* done with all tests */
2227 if (failed)
2228 SCTP_PRINTF("\nSHA1 test results: %d cases failed", failed);
2229 else
2230 SCTP_PRINTF("\nSHA1 test results: all test cases passed");
2231 }
2232
2233 /*
2234 * test assoc key concatenation
2235 */
2236 static int
2237 sctp_test_key_concatenation(sctp_key_t *key1, sctp_key_t *key2,
2238 sctp_key_t *expected_key)
2239 {
2240 sctp_key_t *key;
2241 int ret_val;
2242
2243 sctp_show_key(key1, "\nkey1");
2244 sctp_show_key(key2, "\nkey2");
2245 key = sctp_compute_hashkey(key1, key2, NULL);
2246 sctp_show_key(expected_key, "\nExpected");
2247 sctp_show_key(key, "\nComputed");
2248 if (memcmp(key, expected_key, expected_key->keylen) != 0) {
2249 SCTP_PRINTF("\nFAILED");
2250 ret_val = -1;
2251 } else {
2252 SCTP_PRINTF("\nPASSED");
2253 ret_val = 0;
2254 }
2255 sctp_free_key(key1);
2256 sctp_free_key(key2);
2257 sctp_free_key(expected_key);
2258 sctp_free_key(key);
2259 return (ret_val);
2260 }
2261
2262
2263 void
2264 sctp_test_authkey(void)
2265 {
2266 sctp_key_t *key1, *key2, *expected_key;
2267 int failed = 0;
2268
2269 /* test case 1 */
2270 key1 = sctp_set_key("\x01\x01\x01\x01", 4);
2271 key2 = sctp_set_key("\x01\x02\x03\x04", 4);
2272 expected_key = sctp_set_key("\x01\x01\x01\x01\x01\x02\x03\x04", 8);
2273 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2274 failed++;
2275
2276 /* test case 2 */
2277 key1 = sctp_set_key("\x00\x00\x00\x01", 4);
2278 key2 = sctp_set_key("\x02", 1);
2279 expected_key = sctp_set_key("\x00\x00\x00\x01\x02", 5);
2280 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2281 failed++;
2282
2283 /* test case 3 */
2284 key1 = sctp_set_key("\x01", 1);
2285 key2 = sctp_set_key("\x00\x00\x00\x02", 4);
2286 expected_key = sctp_set_key("\x01\x00\x00\x00\x02", 5);
2287 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2288 failed++;
2289
2290 /* test case 4 */
2291 key1 = sctp_set_key("\x00\x00\x00\x01", 4);
2292 key2 = sctp_set_key("\x01", 1);
2293 expected_key = sctp_set_key("\x01\x00\x00\x00\x01", 5);
2294 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2295 failed++;
2296
2297 /* test case 5 */
2298 key1 = sctp_set_key("\x01", 1);
2299 key2 = sctp_set_key("\x00\x00\x00\x01", 4);
2300 expected_key = sctp_set_key("\x01\x00\x00\x00\x01", 5);
2301 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2302 failed++;
2303
2304 /* test case 6 */
2305 key1 = sctp_set_key("\x00\x00\x00\x00\x01\x02\x03\x04\x05\x06\x07", 11);
2306 key2 = sctp_set_key("\x00\x00\x00\x00\x01\x02\x03\x04\x05\x06\x08", 11);
2307 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);
2308 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2309 failed++;
2310
2311 /* test case 7 */
2312 key1 = sctp_set_key("\x00\x00\x00\x00\x01\x02\x03\x04\x05\x06\x08", 11);
2313 key2 = sctp_set_key("\x00\x00\x00\x00\x01\x02\x03\x04\x05\x06\x07", 11);
2314 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);
2315 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2316 failed++;
2317
2318 /* done with all tests */
2319 if (failed)
2320 SCTP_PRINTF("\nKey concatenation test results: %d cases failed", failed);
2321 else
2322 SCTP_PRINTF("\nKey concatenation test results: all test cases passed");
2323 }
2324
2325
2326 #if defined(STANDALONE_HMAC_TEST)
2327 int
2328 main(void)
2329 {
2330 sctp_test_hmac_sha1();
2331 sctp_test_authkey();
2332 }
2333
2334 #endif /* STANDALONE_HMAC_TEST */
2335
2336 #endif /* SCTP_HMAC_TEST */
2337