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 257804 2013-11-07 18:50:11Z 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 /* is chunk restricted? */
139 if ((chunk == SCTP_ASCONF) ||
140 (chunk == SCTP_ASCONF_ACK)) {
141 return (-1);
142 }
143 if (list->chunks[chunk] == 1) {
144 list->chunks[chunk] = 0;
145 list->num_chunks--;
146 SCTPDBG(SCTP_DEBUG_AUTH1,
147 "SCTP: deleted chunk %u (0x%02x) from Auth list\n",
148 chunk, chunk);
149 }
150 return (0);
151 }
152
153 size_t
sctp_auth_get_chklist_size(const sctp_auth_chklist_t * list)154 sctp_auth_get_chklist_size(const sctp_auth_chklist_t *list)
155 {
156 if (list == NULL)
157 return (0);
158 else
159 return (list->num_chunks);
160 }
161
162 /*
163 * set the default list of chunks requiring AUTH
164 */
165 void
sctp_auth_set_default_chunks(sctp_auth_chklist_t * list)166 sctp_auth_set_default_chunks(sctp_auth_chklist_t *list)
167 {
168 (void)sctp_auth_add_chunk(SCTP_ASCONF, list);
169 (void)sctp_auth_add_chunk(SCTP_ASCONF_ACK, list);
170 }
171
172 /*
173 * return the current number and list of required chunks caller must
174 * guarantee ptr has space for up to 256 bytes
175 */
176 int
sctp_serialize_auth_chunks(const sctp_auth_chklist_t * list,uint8_t * ptr)177 sctp_serialize_auth_chunks(const sctp_auth_chklist_t *list, uint8_t *ptr)
178 {
179 int i, count = 0;
180
181 if (list == NULL)
182 return (0);
183
184 for (i = 0; i < 256; i++) {
185 if (list->chunks[i] != 0) {
186 *ptr++ = i;
187 count++;
188 }
189 }
190 return (count);
191 }
192
193 int
sctp_pack_auth_chunks(const sctp_auth_chklist_t * list,uint8_t * ptr)194 sctp_pack_auth_chunks(const sctp_auth_chklist_t *list, uint8_t *ptr)
195 {
196 int i, size = 0;
197
198 if (list == NULL)
199 return (0);
200
201 if (list->num_chunks <= 32) {
202 /* just list them, one byte each */
203 for (i = 0; i < 256; i++) {
204 if (list->chunks[i] != 0) {
205 *ptr++ = i;
206 size++;
207 }
208 }
209 } else {
210 int index, offset;
211
212 /* pack into a 32 byte bitfield */
213 for (i = 0; i < 256; i++) {
214 if (list->chunks[i] != 0) {
215 index = i / 8;
216 offset = i % 8;
217 ptr[index] |= (1 << offset);
218 }
219 }
220 size = 32;
221 }
222 return (size);
223 }
224
225 int
sctp_unpack_auth_chunks(const uint8_t * ptr,uint8_t num_chunks,sctp_auth_chklist_t * list)226 sctp_unpack_auth_chunks(const uint8_t *ptr, uint8_t num_chunks,
227 sctp_auth_chklist_t *list)
228 {
229 int i;
230 int size;
231
232 if (list == NULL)
233 return (0);
234
235 if (num_chunks <= 32) {
236 /* just pull them, one byte each */
237 for (i = 0; i < num_chunks; i++) {
238 (void)sctp_auth_add_chunk(*ptr++, list);
239 }
240 size = num_chunks;
241 } else {
242 int index, offset;
243
244 /* unpack from a 32 byte bitfield */
245 for (index = 0; index < 32; index++) {
246 for (offset = 0; offset < 8; offset++) {
247 if (ptr[index] & (1 << offset)) {
248 (void)sctp_auth_add_chunk((index * 8) + offset, list);
249 }
250 }
251 }
252 size = 32;
253 }
254 return (size);
255 }
256
257
258 /*
259 * allocate structure space for a key of length keylen
260 */
261 sctp_key_t *
sctp_alloc_key(uint32_t keylen)262 sctp_alloc_key(uint32_t keylen)
263 {
264 sctp_key_t *new_key;
265
266 SCTP_MALLOC(new_key, sctp_key_t *, sizeof(*new_key) + keylen,
267 SCTP_M_AUTH_KY);
268 if (new_key == NULL) {
269 /* out of memory */
270 return (NULL);
271 }
272 new_key->keylen = keylen;
273 return (new_key);
274 }
275
276 void
sctp_free_key(sctp_key_t * key)277 sctp_free_key(sctp_key_t *key)
278 {
279 if (key != NULL)
280 SCTP_FREE(key,SCTP_M_AUTH_KY);
281 }
282
283 void
sctp_print_key(sctp_key_t * key,const char * str)284 sctp_print_key(sctp_key_t *key, const char *str)
285 {
286 uint32_t i;
287
288 if (key == NULL) {
289 SCTP_PRINTF("%s: [Null key]\n", str);
290 return;
291 }
292 SCTP_PRINTF("%s: len %u, ", str, key->keylen);
293 if (key->keylen) {
294 for (i = 0; i < key->keylen; i++)
295 SCTP_PRINTF("%02x", key->key[i]);
296 SCTP_PRINTF("\n");
297 } else {
298 SCTP_PRINTF("[Null key]\n");
299 }
300 }
301
302 void
sctp_show_key(sctp_key_t * key,const char * str)303 sctp_show_key(sctp_key_t *key, const char *str)
304 {
305 uint32_t i;
306
307 if (key == NULL) {
308 SCTP_PRINTF("%s: [Null key]\n", str);
309 return;
310 }
311 SCTP_PRINTF("%s: len %u, ", str, key->keylen);
312 if (key->keylen) {
313 for (i = 0; i < key->keylen; i++)
314 SCTP_PRINTF("%02x", key->key[i]);
315 SCTP_PRINTF("\n");
316 } else {
317 SCTP_PRINTF("[Null key]\n");
318 }
319 }
320
321 static uint32_t
sctp_get_keylen(sctp_key_t * key)322 sctp_get_keylen(sctp_key_t *key)
323 {
324 if (key != NULL)
325 return (key->keylen);
326 else
327 return (0);
328 }
329
330 /*
331 * generate a new random key of length 'keylen'
332 */
333 sctp_key_t *
sctp_generate_random_key(uint32_t keylen)334 sctp_generate_random_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 SCTP_READ_RANDOM(new_key->key, keylen);
344 new_key->keylen = keylen;
345 return (new_key);
346 }
347
348 sctp_key_t *
sctp_set_key(uint8_t * key,uint32_t keylen)349 sctp_set_key(uint8_t *key, uint32_t keylen)
350 {
351 sctp_key_t *new_key;
352
353 new_key = sctp_alloc_key(keylen);
354 if (new_key == NULL) {
355 /* out of memory */
356 return (NULL);
357 }
358 bcopy(key, new_key->key, keylen);
359 return (new_key);
360 }
361
362 /*-
363 * given two keys of variable size, compute which key is "larger/smaller"
364 * returns: 1 if key1 > key2
365 * -1 if key1 < key2
366 * 0 if key1 = key2
367 */
368 static int
sctp_compare_key(sctp_key_t * key1,sctp_key_t * key2)369 sctp_compare_key(sctp_key_t *key1, sctp_key_t *key2)
370 {
371 uint32_t maxlen;
372 uint32_t i;
373 uint32_t key1len, key2len;
374 uint8_t *key_1, *key_2;
375 uint8_t val1, val2;
376
377 /* sanity/length check */
378 key1len = sctp_get_keylen(key1);
379 key2len = sctp_get_keylen(key2);
380 if ((key1len == 0) && (key2len == 0))
381 return (0);
382 else if (key1len == 0)
383 return (-1);
384 else if (key2len == 0)
385 return (1);
386
387 if (key1len < key2len) {
388 maxlen = key2len;
389 } else {
390 maxlen = key1len;
391 }
392 key_1 = key1->key;
393 key_2 = key2->key;
394 /* check for numeric equality */
395 for (i = 0; i < maxlen; i++) {
396 /* left-pad with zeros */
397 val1 = (i < (maxlen - key1len)) ? 0 : *(key_1++);
398 val2 = (i < (maxlen - key2len)) ? 0 : *(key_2++);
399 if (val1 > val2) {
400 return (1);
401 } else if (val1 < val2) {
402 return (-1);
403 }
404 }
405 /* keys are equal value, so check lengths */
406 if (key1len == key2len)
407 return (0);
408 else if (key1len < key2len)
409 return (-1);
410 else
411 return (1);
412 }
413
414 /*
415 * generate the concatenated keying material based on the two keys and the
416 * shared key (if available). draft-ietf-tsvwg-auth specifies the specific
417 * order for concatenation
418 */
419 sctp_key_t *
sctp_compute_hashkey(sctp_key_t * key1,sctp_key_t * key2,sctp_key_t * shared)420 sctp_compute_hashkey(sctp_key_t *key1, sctp_key_t *key2, sctp_key_t *shared)
421 {
422 uint32_t keylen;
423 sctp_key_t *new_key;
424 uint8_t *key_ptr;
425
426 keylen = sctp_get_keylen(key1) + sctp_get_keylen(key2) +
427 sctp_get_keylen(shared);
428
429 if (keylen > 0) {
430 /* get space for the new key */
431 new_key = sctp_alloc_key(keylen);
432 if (new_key == NULL) {
433 /* out of memory */
434 return (NULL);
435 }
436 new_key->keylen = keylen;
437 key_ptr = new_key->key;
438 } else {
439 /* all keys empty/null?! */
440 return (NULL);
441 }
442
443 /* concatenate the keys */
444 if (sctp_compare_key(key1, key2) <= 0) {
445 /* key is shared + key1 + key2 */
446 if (sctp_get_keylen(shared)) {
447 bcopy(shared->key, key_ptr, shared->keylen);
448 key_ptr += shared->keylen;
449 }
450 if (sctp_get_keylen(key1)) {
451 bcopy(key1->key, key_ptr, key1->keylen);
452 key_ptr += key1->keylen;
453 }
454 if (sctp_get_keylen(key2)) {
455 bcopy(key2->key, key_ptr, key2->keylen);
456 }
457 } else {
458 /* key is shared + key2 + key1 */
459 if (sctp_get_keylen(shared)) {
460 bcopy(shared->key, key_ptr, shared->keylen);
461 key_ptr += shared->keylen;
462 }
463 if (sctp_get_keylen(key2)) {
464 bcopy(key2->key, key_ptr, key2->keylen);
465 key_ptr += key2->keylen;
466 }
467 if (sctp_get_keylen(key1)) {
468 bcopy(key1->key, key_ptr, key1->keylen);
469 }
470 }
471 return (new_key);
472 }
473
474
475 sctp_sharedkey_t *
sctp_alloc_sharedkey(void)476 sctp_alloc_sharedkey(void)
477 {
478 sctp_sharedkey_t *new_key;
479
480 SCTP_MALLOC(new_key, sctp_sharedkey_t *, sizeof(*new_key),
481 SCTP_M_AUTH_KY);
482 if (new_key == NULL) {
483 /* out of memory */
484 return (NULL);
485 }
486 new_key->keyid = 0;
487 new_key->key = NULL;
488 new_key->refcount = 1;
489 new_key->deactivated = 0;
490 return (new_key);
491 }
492
493 void
sctp_free_sharedkey(sctp_sharedkey_t * skey)494 sctp_free_sharedkey(sctp_sharedkey_t *skey)
495 {
496 if (skey == NULL)
497 return;
498
499 if (SCTP_DECREMENT_AND_CHECK_REFCOUNT(&skey->refcount)) {
500 if (skey->key != NULL)
501 sctp_free_key(skey->key);
502 SCTP_FREE(skey, SCTP_M_AUTH_KY);
503 }
504 }
505
506 sctp_sharedkey_t *
sctp_find_sharedkey(struct sctp_keyhead * shared_keys,uint16_t key_id)507 sctp_find_sharedkey(struct sctp_keyhead *shared_keys, uint16_t key_id)
508 {
509 sctp_sharedkey_t *skey;
510
511 LIST_FOREACH(skey, shared_keys, next) {
512 if (skey->keyid == key_id)
513 return (skey);
514 }
515 return (NULL);
516 }
517
518 int
sctp_insert_sharedkey(struct sctp_keyhead * shared_keys,sctp_sharedkey_t * new_skey)519 sctp_insert_sharedkey(struct sctp_keyhead *shared_keys,
520 sctp_sharedkey_t *new_skey)
521 {
522 sctp_sharedkey_t *skey;
523
524 if ((shared_keys == NULL) || (new_skey == NULL))
525 return (EINVAL);
526
527 /* insert into an empty list? */
528 if (LIST_EMPTY(shared_keys)) {
529 LIST_INSERT_HEAD(shared_keys, new_skey, next);
530 return (0);
531 }
532 /* insert into the existing list, ordered by key id */
533 LIST_FOREACH(skey, shared_keys, next) {
534 if (new_skey->keyid < skey->keyid) {
535 /* insert it before here */
536 LIST_INSERT_BEFORE(skey, new_skey, next);
537 return (0);
538 } else if (new_skey->keyid == skey->keyid) {
539 /* replace the existing key */
540 /* verify this key *can* be replaced */
541 if ((skey->deactivated) && (skey->refcount > 1)) {
542 SCTPDBG(SCTP_DEBUG_AUTH1,
543 "can't replace shared key id %u\n",
544 new_skey->keyid);
545 return (EBUSY);
546 }
547 SCTPDBG(SCTP_DEBUG_AUTH1,
548 "replacing shared key id %u\n",
549 new_skey->keyid);
550 LIST_INSERT_BEFORE(skey, new_skey, next);
551 LIST_REMOVE(skey, next);
552 sctp_free_sharedkey(skey);
553 return (0);
554 }
555 if (LIST_NEXT(skey, next) == NULL) {
556 /* belongs at the end of the list */
557 LIST_INSERT_AFTER(skey, new_skey, next);
558 return (0);
559 }
560 }
561 /* shouldn't reach here */
562 return (0);
563 }
564
565 void
sctp_auth_key_acquire(struct sctp_tcb * stcb,uint16_t key_id)566 sctp_auth_key_acquire(struct sctp_tcb *stcb, uint16_t key_id)
567 {
568 sctp_sharedkey_t *skey;
569
570 /* find the shared key */
571 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, key_id);
572
573 /* bump the ref count */
574 if (skey) {
575 atomic_add_int(&skey->refcount, 1);
576 SCTPDBG(SCTP_DEBUG_AUTH2,
577 "%s: stcb %p key %u refcount acquire to %d\n",
578 __FUNCTION__, (void *)stcb, key_id, skey->refcount);
579 }
580 }
581
582 void
sctp_auth_key_release(struct sctp_tcb * stcb,uint16_t key_id,int so_locked SCTP_UNUSED)583 sctp_auth_key_release(struct sctp_tcb *stcb, uint16_t key_id, int so_locked
584 #if !defined(__APPLE__) && !defined(SCTP_SO_LOCK_TESTING)
585 SCTP_UNUSED
586 #endif
587 )
588 {
589 sctp_sharedkey_t *skey;
590
591 /* find the shared key */
592 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, key_id);
593
594 /* decrement the ref count */
595 if (skey) {
596 sctp_free_sharedkey(skey);
597 SCTPDBG(SCTP_DEBUG_AUTH2,
598 "%s: stcb %p key %u refcount release to %d\n",
599 __FUNCTION__, (void *)stcb, key_id, skey->refcount);
600
601 /* see if a notification should be generated */
602 if ((skey->refcount <= 1) && (skey->deactivated)) {
603 /* notify ULP that key is no longer used */
604 sctp_ulp_notify(SCTP_NOTIFY_AUTH_FREE_KEY, stcb,
605 key_id, 0, so_locked);
606 SCTPDBG(SCTP_DEBUG_AUTH2,
607 "%s: stcb %p key %u no longer used, %d\n",
608 __FUNCTION__, (void *)stcb, key_id, skey->refcount);
609 }
610 }
611 }
612
613 static sctp_sharedkey_t *
sctp_copy_sharedkey(const sctp_sharedkey_t * skey)614 sctp_copy_sharedkey(const sctp_sharedkey_t *skey)
615 {
616 sctp_sharedkey_t *new_skey;
617
618 if (skey == NULL)
619 return (NULL);
620 new_skey = sctp_alloc_sharedkey();
621 if (new_skey == NULL)
622 return (NULL);
623 if (skey->key != NULL)
624 new_skey->key = sctp_set_key(skey->key->key, skey->key->keylen);
625 else
626 new_skey->key = NULL;
627 new_skey->keyid = skey->keyid;
628 return (new_skey);
629 }
630
631 int
sctp_copy_skeylist(const struct sctp_keyhead * src,struct sctp_keyhead * dest)632 sctp_copy_skeylist(const struct sctp_keyhead *src, struct sctp_keyhead *dest)
633 {
634 sctp_sharedkey_t *skey, *new_skey;
635 int count = 0;
636
637 if ((src == NULL) || (dest == NULL))
638 return (0);
639 LIST_FOREACH(skey, src, next) {
640 new_skey = sctp_copy_sharedkey(skey);
641 if (new_skey != NULL) {
642 (void)sctp_insert_sharedkey(dest, new_skey);
643 count++;
644 }
645 }
646 return (count);
647 }
648
649
650 sctp_hmaclist_t *
sctp_alloc_hmaclist(uint8_t num_hmacs)651 sctp_alloc_hmaclist(uint8_t num_hmacs)
652 {
653 sctp_hmaclist_t *new_list;
654 int alloc_size;
655
656 alloc_size = sizeof(*new_list) + num_hmacs * sizeof(new_list->hmac[0]);
657 SCTP_MALLOC(new_list, sctp_hmaclist_t *, alloc_size,
658 SCTP_M_AUTH_HL);
659 if (new_list == NULL) {
660 /* out of memory */
661 return (NULL);
662 }
663 new_list->max_algo = num_hmacs;
664 new_list->num_algo = 0;
665 return (new_list);
666 }
667
668 void
sctp_free_hmaclist(sctp_hmaclist_t * list)669 sctp_free_hmaclist(sctp_hmaclist_t *list)
670 {
671 if (list != NULL) {
672 SCTP_FREE(list,SCTP_M_AUTH_HL);
673 list = NULL;
674 }
675 }
676
677 int
sctp_auth_add_hmacid(sctp_hmaclist_t * list,uint16_t hmac_id)678 sctp_auth_add_hmacid(sctp_hmaclist_t *list, uint16_t hmac_id)
679 {
680 int i;
681 if (list == NULL)
682 return (-1);
683 if (list->num_algo == list->max_algo) {
684 SCTPDBG(SCTP_DEBUG_AUTH1,
685 "SCTP: HMAC id list full, ignoring add %u\n", hmac_id);
686 return (-1);
687 }
688 #if defined(SCTP_SUPPORT_HMAC_SHA256)
689 if ((hmac_id != SCTP_AUTH_HMAC_ID_SHA1) &&
690 (hmac_id != SCTP_AUTH_HMAC_ID_SHA256)) {
691 #else
692 if (hmac_id != SCTP_AUTH_HMAC_ID_SHA1) {
693 #endif
694 return (-1);
695 }
696 /* Now is it already in the list */
697 for (i = 0; i < list->num_algo; i++) {
698 if (list->hmac[i] == hmac_id) {
699 /* already in list */
700 return (-1);
701 }
702 }
703 SCTPDBG(SCTP_DEBUG_AUTH1, "SCTP: add HMAC id %u to list\n", hmac_id);
704 list->hmac[list->num_algo++] = hmac_id;
705 return (0);
706 }
707
708 sctp_hmaclist_t *
709 sctp_copy_hmaclist(sctp_hmaclist_t *list)
710 {
711 sctp_hmaclist_t *new_list;
712 int i;
713
714 if (list == NULL)
715 return (NULL);
716 /* get a new list */
717 new_list = sctp_alloc_hmaclist(list->max_algo);
718 if (new_list == NULL)
719 return (NULL);
720 /* copy it */
721 new_list->max_algo = list->max_algo;
722 new_list->num_algo = list->num_algo;
723 for (i = 0; i < list->num_algo; i++)
724 new_list->hmac[i] = list->hmac[i];
725 return (new_list);
726 }
727
728 sctp_hmaclist_t *
729 sctp_default_supported_hmaclist(void)
730 {
731 sctp_hmaclist_t *new_list;
732
733 #if defined(SCTP_SUPPORT_HMAC_SHA256)
734 new_list = sctp_alloc_hmaclist(2);
735 #else
736 new_list = sctp_alloc_hmaclist(1);
737 #endif
738 if (new_list == NULL)
739 return (NULL);
740 #if defined(SCTP_SUPPORT_HMAC_SHA256)
741 /* We prefer SHA256, so list it first */
742 (void)sctp_auth_add_hmacid(new_list, SCTP_AUTH_HMAC_ID_SHA256);
743 #endif
744 (void)sctp_auth_add_hmacid(new_list, SCTP_AUTH_HMAC_ID_SHA1);
745 return (new_list);
746 }
747
748 /*-
749 * HMAC algos are listed in priority/preference order
750 * find the best HMAC id to use for the peer based on local support
751 */
752 uint16_t
753 sctp_negotiate_hmacid(sctp_hmaclist_t *peer, sctp_hmaclist_t *local)
754 {
755 int i, j;
756
757 if ((local == NULL) || (peer == NULL))
758 return (SCTP_AUTH_HMAC_ID_RSVD);
759
760 for (i = 0; i < peer->num_algo; i++) {
761 for (j = 0; j < local->num_algo; j++) {
762 if (peer->hmac[i] == local->hmac[j]) {
763 /* found the "best" one */
764 SCTPDBG(SCTP_DEBUG_AUTH1,
765 "SCTP: negotiated peer HMAC id %u\n",
766 peer->hmac[i]);
767 return (peer->hmac[i]);
768 }
769 }
770 }
771 /* didn't find one! */
772 return (SCTP_AUTH_HMAC_ID_RSVD);
773 }
774
775 /*-
776 * serialize the HMAC algo list and return space used
777 * caller must guarantee ptr has appropriate space
778 */
779 int
780 sctp_serialize_hmaclist(sctp_hmaclist_t *list, uint8_t *ptr)
781 {
782 int i;
783 uint16_t hmac_id;
784
785 if (list == NULL)
786 return (0);
787
788 for (i = 0; i < list->num_algo; i++) {
789 hmac_id = htons(list->hmac[i]);
790 bcopy(&hmac_id, ptr, sizeof(hmac_id));
791 ptr += sizeof(hmac_id);
792 }
793 return (list->num_algo * sizeof(hmac_id));
794 }
795
796 int
797 sctp_verify_hmac_param (struct sctp_auth_hmac_algo *hmacs, uint32_t num_hmacs)
798 {
799 uint32_t i;
800
801 for (i = 0; i < num_hmacs; i++) {
802 if (ntohs(hmacs->hmac_ids[i]) == SCTP_AUTH_HMAC_ID_SHA1) {
803 return (0);
804 }
805 }
806 return (-1);
807 }
808
809 sctp_authinfo_t *
810 sctp_alloc_authinfo(void)
811 {
812 sctp_authinfo_t *new_authinfo;
813
814 SCTP_MALLOC(new_authinfo, sctp_authinfo_t *, sizeof(*new_authinfo),
815 SCTP_M_AUTH_IF);
816
817 if (new_authinfo == NULL) {
818 /* out of memory */
819 return (NULL);
820 }
821 bzero(new_authinfo, sizeof(*new_authinfo));
822 return (new_authinfo);
823 }
824
825 void
826 sctp_free_authinfo(sctp_authinfo_t *authinfo)
827 {
828 if (authinfo == NULL)
829 return;
830
831 if (authinfo->random != NULL)
832 sctp_free_key(authinfo->random);
833 if (authinfo->peer_random != NULL)
834 sctp_free_key(authinfo->peer_random);
835 if (authinfo->assoc_key != NULL)
836 sctp_free_key(authinfo->assoc_key);
837 if (authinfo->recv_key != NULL)
838 sctp_free_key(authinfo->recv_key);
839
840 /* We are NOT dynamically allocating authinfo's right now... */
841 /* SCTP_FREE(authinfo, SCTP_M_AUTH_??); */
842 }
843
844
845 uint32_t
846 sctp_get_auth_chunk_len(uint16_t hmac_algo)
847 {
848 int size;
849
850 size = sizeof(struct sctp_auth_chunk) + sctp_get_hmac_digest_len(hmac_algo);
851 return (SCTP_SIZE32(size));
852 }
853
854 uint32_t
855 sctp_get_hmac_digest_len(uint16_t hmac_algo)
856 {
857 switch (hmac_algo) {
858 case SCTP_AUTH_HMAC_ID_SHA1:
859 return (SCTP_AUTH_DIGEST_LEN_SHA1);
860 #if defined(SCTP_SUPPORT_HMAC_SHA256)
861 case SCTP_AUTH_HMAC_ID_SHA256:
862 return (SCTP_AUTH_DIGEST_LEN_SHA256);
863 #endif
864 default:
865 /* unknown HMAC algorithm: can't do anything */
866 return (0);
867 } /* end switch */
868 }
869
870 static inline int
871 sctp_get_hmac_block_len(uint16_t hmac_algo)
872 {
873 switch (hmac_algo) {
874 case SCTP_AUTH_HMAC_ID_SHA1:
875 return (64);
876 #if defined(SCTP_SUPPORT_HMAC_SHA256)
877 case SCTP_AUTH_HMAC_ID_SHA256:
878 return (64);
879 #endif
880 case SCTP_AUTH_HMAC_ID_RSVD:
881 default:
882 /* unknown HMAC algorithm: can't do anything */
883 return (0);
884 } /* end switch */
885 }
886
887 #if defined(__Userspace__)
888 /* __Userspace__ SHA1_Init is defined in libcrypto.a (libssl-dev on Ubuntu) */
889 #endif
890 static void
891 sctp_hmac_init(uint16_t hmac_algo, sctp_hash_context_t *ctx)
892 {
893 switch (hmac_algo) {
894 case SCTP_AUTH_HMAC_ID_SHA1:
895 SCTP_SHA1_INIT(&ctx->sha1);
896 break;
897 #if defined(SCTP_SUPPORT_HMAC_SHA256)
898 case SCTP_AUTH_HMAC_ID_SHA256:
899 SCTP_SHA256_INIT(&ctx->sha256);
900 break;
901 #endif
902 case SCTP_AUTH_HMAC_ID_RSVD:
903 default:
904 /* unknown HMAC algorithm: can't do anything */
905 return;
906 } /* end switch */
907 }
908
909 static void
910 sctp_hmac_update(uint16_t hmac_algo, sctp_hash_context_t *ctx,
911 uint8_t *text, uint32_t textlen)
912 {
913 switch (hmac_algo) {
914 case SCTP_AUTH_HMAC_ID_SHA1:
915 SCTP_SHA1_UPDATE(&ctx->sha1, text, textlen);
916 break;
917 #if defined(SCTP_SUPPORT_HMAC_SHA256)
918 case SCTP_AUTH_HMAC_ID_SHA256:
919 SCTP_SHA256_UPDATE(&ctx->sha256, text, textlen);
920 break;
921 #endif
922 case SCTP_AUTH_HMAC_ID_RSVD:
923 default:
924 /* unknown HMAC algorithm: can't do anything */
925 return;
926 } /* end switch */
927 }
928
929 static void
930 sctp_hmac_final(uint16_t hmac_algo, sctp_hash_context_t *ctx,
931 uint8_t *digest)
932 {
933 switch (hmac_algo) {
934 case SCTP_AUTH_HMAC_ID_SHA1:
935 SCTP_SHA1_FINAL(digest, &ctx->sha1);
936 break;
937 #if defined(SCTP_SUPPORT_HMAC_SHA256)
938 case SCTP_AUTH_HMAC_ID_SHA256:
939 SCTP_SHA256_FINAL(digest, &ctx->sha256);
940 break;
941 #endif
942 case SCTP_AUTH_HMAC_ID_RSVD:
943 default:
944 /* unknown HMAC algorithm: can't do anything */
945 return;
946 } /* end switch */
947 }
948
949 /*-
950 * Keyed-Hashing for Message Authentication: FIPS 198 (RFC 2104)
951 *
952 * Compute the HMAC digest using the desired hash key, text, and HMAC
953 * algorithm. Resulting digest is placed in 'digest' and digest length
954 * is returned, if the HMAC was performed.
955 *
956 * WARNING: it is up to the caller to supply sufficient space to hold the
957 * resultant digest.
958 */
959 uint32_t
960 sctp_hmac(uint16_t hmac_algo, uint8_t *key, uint32_t keylen,
961 uint8_t *text, uint32_t textlen, uint8_t *digest)
962 {
963 uint32_t digestlen;
964 uint32_t blocklen;
965 sctp_hash_context_t ctx;
966 uint8_t ipad[128], opad[128]; /* keyed hash inner/outer pads */
967 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
968 uint32_t i;
969
970 /* sanity check the material and length */
971 if ((key == NULL) || (keylen == 0) || (text == NULL) ||
972 (textlen == 0) || (digest == NULL)) {
973 /* can't do HMAC with empty key or text or digest store */
974 return (0);
975 }
976 /* validate the hmac algo and get the digest length */
977 digestlen = sctp_get_hmac_digest_len(hmac_algo);
978 if (digestlen == 0)
979 return (0);
980
981 /* hash the key if it is longer than the hash block size */
982 blocklen = sctp_get_hmac_block_len(hmac_algo);
983 if (keylen > blocklen) {
984 sctp_hmac_init(hmac_algo, &ctx);
985 sctp_hmac_update(hmac_algo, &ctx, key, keylen);
986 sctp_hmac_final(hmac_algo, &ctx, temp);
987 /* set the hashed key as the key */
988 keylen = digestlen;
989 key = temp;
990 }
991 /* initialize the inner/outer pads with the key and "append" zeroes */
992 bzero(ipad, blocklen);
993 bzero(opad, blocklen);
994 bcopy(key, ipad, keylen);
995 bcopy(key, opad, keylen);
996
997 /* XOR the key with ipad and opad values */
998 for (i = 0; i < blocklen; i++) {
999 ipad[i] ^= 0x36;
1000 opad[i] ^= 0x5c;
1001 }
1002
1003 /* perform inner hash */
1004 sctp_hmac_init(hmac_algo, &ctx);
1005 sctp_hmac_update(hmac_algo, &ctx, ipad, blocklen);
1006 sctp_hmac_update(hmac_algo, &ctx, text, textlen);
1007 sctp_hmac_final(hmac_algo, &ctx, temp);
1008
1009 /* perform outer hash */
1010 sctp_hmac_init(hmac_algo, &ctx);
1011 sctp_hmac_update(hmac_algo, &ctx, opad, blocklen);
1012 sctp_hmac_update(hmac_algo, &ctx, temp, digestlen);
1013 sctp_hmac_final(hmac_algo, &ctx, digest);
1014
1015 return (digestlen);
1016 }
1017
1018 /* mbuf version */
1019 uint32_t
1020 sctp_hmac_m(uint16_t hmac_algo, uint8_t *key, uint32_t keylen,
1021 struct mbuf *m, uint32_t m_offset, uint8_t *digest, uint32_t trailer)
1022 {
1023 uint32_t digestlen;
1024 uint32_t blocklen;
1025 sctp_hash_context_t ctx;
1026 uint8_t ipad[128], opad[128]; /* keyed hash inner/outer pads */
1027 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
1028 uint32_t i;
1029 struct mbuf *m_tmp;
1030
1031 /* sanity check the material and length */
1032 if ((key == NULL) || (keylen == 0) || (m == NULL) || (digest == NULL)) {
1033 /* can't do HMAC with empty key or text or digest store */
1034 return (0);
1035 }
1036 /* validate the hmac algo and get the digest length */
1037 digestlen = sctp_get_hmac_digest_len(hmac_algo);
1038 if (digestlen == 0)
1039 return (0);
1040
1041 /* hash the key if it is longer than the hash block size */
1042 blocklen = sctp_get_hmac_block_len(hmac_algo);
1043 if (keylen > blocklen) {
1044 sctp_hmac_init(hmac_algo, &ctx);
1045 sctp_hmac_update(hmac_algo, &ctx, key, keylen);
1046 sctp_hmac_final(hmac_algo, &ctx, temp);
1047 /* set the hashed key as the key */
1048 keylen = digestlen;
1049 key = temp;
1050 }
1051 /* initialize the inner/outer pads with the key and "append" zeroes */
1052 bzero(ipad, blocklen);
1053 bzero(opad, blocklen);
1054 bcopy(key, ipad, keylen);
1055 bcopy(key, opad, keylen);
1056
1057 /* XOR the key with ipad and opad values */
1058 for (i = 0; i < blocklen; i++) {
1059 ipad[i] ^= 0x36;
1060 opad[i] ^= 0x5c;
1061 }
1062
1063 /* perform inner hash */
1064 sctp_hmac_init(hmac_algo, &ctx);
1065 sctp_hmac_update(hmac_algo, &ctx, ipad, blocklen);
1066 /* find the correct starting mbuf and offset (get start of text) */
1067 m_tmp = m;
1068 while ((m_tmp != NULL) && (m_offset >= (uint32_t) SCTP_BUF_LEN(m_tmp))) {
1069 m_offset -= SCTP_BUF_LEN(m_tmp);
1070 m_tmp = SCTP_BUF_NEXT(m_tmp);
1071 }
1072 /* now use the rest of the mbuf chain for the text */
1073 while (m_tmp != NULL) {
1074 if ((SCTP_BUF_NEXT(m_tmp) == NULL) && trailer) {
1075 sctp_hmac_update(hmac_algo, &ctx, mtod(m_tmp, uint8_t *) + m_offset,
1076 SCTP_BUF_LEN(m_tmp) - (trailer+m_offset));
1077 } else {
1078 sctp_hmac_update(hmac_algo, &ctx, mtod(m_tmp, uint8_t *) + m_offset,
1079 SCTP_BUF_LEN(m_tmp) - m_offset);
1080 }
1081
1082 /* clear the offset since it's only for the first mbuf */
1083 m_offset = 0;
1084 m_tmp = SCTP_BUF_NEXT(m_tmp);
1085 }
1086 sctp_hmac_final(hmac_algo, &ctx, temp);
1087
1088 /* perform outer hash */
1089 sctp_hmac_init(hmac_algo, &ctx);
1090 sctp_hmac_update(hmac_algo, &ctx, opad, blocklen);
1091 sctp_hmac_update(hmac_algo, &ctx, temp, digestlen);
1092 sctp_hmac_final(hmac_algo, &ctx, digest);
1093
1094 return (digestlen);
1095 }
1096
1097 /*-
1098 * verify the HMAC digest using the desired hash key, text, and HMAC
1099 * algorithm.
1100 * Returns -1 on error, 0 on success.
1101 */
1102 int
1103 sctp_verify_hmac(uint16_t hmac_algo, uint8_t *key, uint32_t keylen,
1104 uint8_t *text, uint32_t textlen,
1105 uint8_t *digest, uint32_t digestlen)
1106 {
1107 uint32_t len;
1108 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
1109
1110 /* sanity check the material and length */
1111 if ((key == NULL) || (keylen == 0) ||
1112 (text == NULL) || (textlen == 0) || (digest == NULL)) {
1113 /* can't do HMAC with empty key or text or digest */
1114 return (-1);
1115 }
1116 len = sctp_get_hmac_digest_len(hmac_algo);
1117 if ((len == 0) || (digestlen != len))
1118 return (-1);
1119
1120 /* compute the expected hash */
1121 if (sctp_hmac(hmac_algo, key, keylen, text, textlen, temp) != len)
1122 return (-1);
1123
1124 if (memcmp(digest, temp, digestlen) != 0)
1125 return (-1);
1126 else
1127 return (0);
1128 }
1129
1130
1131 /*
1132 * computes the requested HMAC using a key struct (which may be modified if
1133 * the keylen exceeds the HMAC block len).
1134 */
1135 uint32_t
1136 sctp_compute_hmac(uint16_t hmac_algo, sctp_key_t *key, uint8_t *text,
1137 uint32_t textlen, uint8_t *digest)
1138 {
1139 uint32_t digestlen;
1140 uint32_t blocklen;
1141 sctp_hash_context_t ctx;
1142 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
1143
1144 /* sanity check */
1145 if ((key == NULL) || (text == NULL) || (textlen == 0) ||
1146 (digest == NULL)) {
1147 /* can't do HMAC with empty key or text or digest store */
1148 return (0);
1149 }
1150 /* validate the hmac algo and get the digest length */
1151 digestlen = sctp_get_hmac_digest_len(hmac_algo);
1152 if (digestlen == 0)
1153 return (0);
1154
1155 /* hash the key if it is longer than the hash block size */
1156 blocklen = sctp_get_hmac_block_len(hmac_algo);
1157 if (key->keylen > blocklen) {
1158 sctp_hmac_init(hmac_algo, &ctx);
1159 sctp_hmac_update(hmac_algo, &ctx, key->key, key->keylen);
1160 sctp_hmac_final(hmac_algo, &ctx, temp);
1161 /* save the hashed key as the new key */
1162 key->keylen = digestlen;
1163 bcopy(temp, key->key, key->keylen);
1164 }
1165 return (sctp_hmac(hmac_algo, key->key, key->keylen, text, textlen,
1166 digest));
1167 }
1168
1169 /* mbuf version */
1170 uint32_t
1171 sctp_compute_hmac_m(uint16_t hmac_algo, sctp_key_t *key, struct mbuf *m,
1172 uint32_t m_offset, uint8_t *digest)
1173 {
1174 uint32_t digestlen;
1175 uint32_t blocklen;
1176 sctp_hash_context_t ctx;
1177 uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
1178
1179 /* sanity check */
1180 if ((key == NULL) || (m == NULL) || (digest == NULL)) {
1181 /* can't do HMAC with empty key or text or digest store */
1182 return (0);
1183 }
1184 /* validate the hmac algo and get the digest length */
1185 digestlen = sctp_get_hmac_digest_len(hmac_algo);
1186 if (digestlen == 0)
1187 return (0);
1188
1189 /* hash the key if it is longer than the hash block size */
1190 blocklen = sctp_get_hmac_block_len(hmac_algo);
1191 if (key->keylen > blocklen) {
1192 sctp_hmac_init(hmac_algo, &ctx);
1193 sctp_hmac_update(hmac_algo, &ctx, key->key, key->keylen);
1194 sctp_hmac_final(hmac_algo, &ctx, temp);
1195 /* save the hashed key as the new key */
1196 key->keylen = digestlen;
1197 bcopy(temp, key->key, key->keylen);
1198 }
1199 return (sctp_hmac_m(hmac_algo, key->key, key->keylen, m, m_offset, digest, 0));
1200 }
1201
1202 int
1203 sctp_auth_is_supported_hmac(sctp_hmaclist_t *list, uint16_t id)
1204 {
1205 int i;
1206
1207 if ((list == NULL) || (id == SCTP_AUTH_HMAC_ID_RSVD))
1208 return (0);
1209
1210 for (i = 0; i < list->num_algo; i++)
1211 if (list->hmac[i] == id)
1212 return (1);
1213
1214 /* not in the list */
1215 return (0);
1216 }
1217
1218
1219 /*-
1220 * clear any cached key(s) if they match the given key id on an association.
1221 * the cached key(s) will be recomputed and re-cached at next use.
1222 * ASSUMES TCB_LOCK is already held
1223 */
1224 void
1225 sctp_clear_cachedkeys(struct sctp_tcb *stcb, uint16_t keyid)
1226 {
1227 if (stcb == NULL)
1228 return;
1229
1230 if (keyid == stcb->asoc.authinfo.assoc_keyid) {
1231 sctp_free_key(stcb->asoc.authinfo.assoc_key);
1232 stcb->asoc.authinfo.assoc_key = NULL;
1233 }
1234 if (keyid == stcb->asoc.authinfo.recv_keyid) {
1235 sctp_free_key(stcb->asoc.authinfo.recv_key);
1236 stcb->asoc.authinfo.recv_key = NULL;
1237 }
1238 }
1239
1240 /*-
1241 * clear any cached key(s) if they match the given key id for all assocs on
1242 * an endpoint.
1243 * ASSUMES INP_WLOCK is already held
1244 */
1245 void
1246 sctp_clear_cachedkeys_ep(struct sctp_inpcb *inp, uint16_t keyid)
1247 {
1248 struct sctp_tcb *stcb;
1249
1250 if (inp == NULL)
1251 return;
1252
1253 /* clear the cached keys on all assocs on this instance */
1254 LIST_FOREACH(stcb, &inp->sctp_asoc_list, sctp_tcblist) {
1255 SCTP_TCB_LOCK(stcb);
1256 sctp_clear_cachedkeys(stcb, keyid);
1257 SCTP_TCB_UNLOCK(stcb);
1258 }
1259 }
1260
1261 /*-
1262 * delete a shared key from an association
1263 * ASSUMES TCB_LOCK is already held
1264 */
1265 int
1266 sctp_delete_sharedkey(struct sctp_tcb *stcb, uint16_t keyid)
1267 {
1268 sctp_sharedkey_t *skey;
1269
1270 if (stcb == NULL)
1271 return (-1);
1272
1273 /* is the keyid the assoc active sending key */
1274 if (keyid == stcb->asoc.authinfo.active_keyid)
1275 return (-1);
1276
1277 /* does the key exist? */
1278 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
1279 if (skey == NULL)
1280 return (-1);
1281
1282 /* are there other refcount holders on the key? */
1283 if (skey->refcount > 1)
1284 return (-1);
1285
1286 /* remove it */
1287 LIST_REMOVE(skey, next);
1288 sctp_free_sharedkey(skey); /* frees skey->key as well */
1289
1290 /* clear any cached keys */
1291 sctp_clear_cachedkeys(stcb, keyid);
1292 return (0);
1293 }
1294
1295 /*-
1296 * deletes a shared key from the endpoint
1297 * ASSUMES INP_WLOCK is already held
1298 */
1299 int
1300 sctp_delete_sharedkey_ep(struct sctp_inpcb *inp, uint16_t keyid)
1301 {
1302 sctp_sharedkey_t *skey;
1303
1304 if (inp == NULL)
1305 return (-1);
1306
1307 /* is the keyid the active sending key on the endpoint */
1308 if (keyid == inp->sctp_ep.default_keyid)
1309 return (-1);
1310
1311 /* does the key exist? */
1312 skey = sctp_find_sharedkey(&inp->sctp_ep.shared_keys, keyid);
1313 if (skey == NULL)
1314 return (-1);
1315
1316 /* endpoint keys are not refcounted */
1317
1318 /* remove it */
1319 LIST_REMOVE(skey, next);
1320 sctp_free_sharedkey(skey); /* frees skey->key as well */
1321
1322 /* clear any cached keys */
1323 sctp_clear_cachedkeys_ep(inp, keyid);
1324 return (0);
1325 }
1326
1327 /*-
1328 * set the active key on an association
1329 * ASSUMES TCB_LOCK is already held
1330 */
1331 int
1332 sctp_auth_setactivekey(struct sctp_tcb *stcb, uint16_t keyid)
1333 {
1334 sctp_sharedkey_t *skey = NULL;
1335
1336 /* find the key on the assoc */
1337 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
1338 if (skey == NULL) {
1339 /* that key doesn't exist */
1340 return (-1);
1341 }
1342 if ((skey->deactivated) && (skey->refcount > 1)) {
1343 /* can't reactivate a deactivated key with other refcounts */
1344 return (-1);
1345 }
1346
1347 /* set the (new) active key */
1348 stcb->asoc.authinfo.active_keyid = keyid;
1349 /* reset the deactivated flag */
1350 skey->deactivated = 0;
1351
1352 return (0);
1353 }
1354
1355 /*-
1356 * set the active key on an endpoint
1357 * ASSUMES INP_WLOCK is already held
1358 */
1359 int
1360 sctp_auth_setactivekey_ep(struct sctp_inpcb *inp, uint16_t keyid)
1361 {
1362 sctp_sharedkey_t *skey;
1363
1364 /* find the key */
1365 skey = sctp_find_sharedkey(&inp->sctp_ep.shared_keys, keyid);
1366 if (skey == NULL) {
1367 /* that key doesn't exist */
1368 return (-1);
1369 }
1370 inp->sctp_ep.default_keyid = keyid;
1371 return (0);
1372 }
1373
1374 /*-
1375 * deactivates a shared key from the association
1376 * ASSUMES INP_WLOCK is already held
1377 */
1378 int
1379 sctp_deact_sharedkey(struct sctp_tcb *stcb, uint16_t keyid)
1380 {
1381 sctp_sharedkey_t *skey;
1382
1383 if (stcb == NULL)
1384 return (-1);
1385
1386 /* is the keyid the assoc active sending key */
1387 if (keyid == stcb->asoc.authinfo.active_keyid)
1388 return (-1);
1389
1390 /* does the key exist? */
1391 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
1392 if (skey == NULL)
1393 return (-1);
1394
1395 /* are there other refcount holders on the key? */
1396 if (skey->refcount == 1) {
1397 /* no other users, send a notification for this key */
1398 sctp_ulp_notify(SCTP_NOTIFY_AUTH_FREE_KEY, stcb, keyid, 0,
1399 SCTP_SO_LOCKED);
1400 }
1401
1402 /* mark the key as deactivated */
1403 skey->deactivated = 1;
1404
1405 return (0);
1406 }
1407
1408 /*-
1409 * deactivates a shared key from the endpoint
1410 * ASSUMES INP_WLOCK is already held
1411 */
1412 int
1413 sctp_deact_sharedkey_ep(struct sctp_inpcb *inp, uint16_t keyid)
1414 {
1415 sctp_sharedkey_t *skey;
1416
1417 if (inp == NULL)
1418 return (-1);
1419
1420 /* is the keyid the active sending key on the endpoint */
1421 if (keyid == inp->sctp_ep.default_keyid)
1422 return (-1);
1423
1424 /* does the key exist? */
1425 skey = sctp_find_sharedkey(&inp->sctp_ep.shared_keys, keyid);
1426 if (skey == NULL)
1427 return (-1);
1428
1429 /* endpoint keys are not refcounted */
1430
1431 /* remove it */
1432 LIST_REMOVE(skey, next);
1433 sctp_free_sharedkey(skey); /* frees skey->key as well */
1434
1435 return (0);
1436 }
1437
1438 /*
1439 * get local authentication parameters from cookie (from INIT-ACK)
1440 */
1441 void
1442 sctp_auth_get_cookie_params(struct sctp_tcb *stcb, struct mbuf *m,
1443 uint32_t offset, uint32_t length)
1444 {
1445 struct sctp_paramhdr *phdr, tmp_param;
1446 uint16_t plen, ptype;
1447 uint8_t random_store[SCTP_PARAM_BUFFER_SIZE];
1448 struct sctp_auth_random *p_random = NULL;
1449 uint16_t random_len = 0;
1450 uint8_t hmacs_store[SCTP_PARAM_BUFFER_SIZE];
1451 struct sctp_auth_hmac_algo *hmacs = NULL;
1452 uint16_t hmacs_len = 0;
1453 uint8_t chunks_store[SCTP_PARAM_BUFFER_SIZE];
1454 struct sctp_auth_chunk_list *chunks = NULL;
1455 uint16_t num_chunks = 0;
1456 sctp_key_t *new_key;
1457 uint32_t keylen;
1458
1459 /* convert to upper bound */
1460 length += offset;
1461
1462 phdr = (struct sctp_paramhdr *)sctp_m_getptr(m, offset,
1463 sizeof(struct sctp_paramhdr), (uint8_t *)&tmp_param);
1464 while (phdr != NULL) {
1465 ptype = ntohs(phdr->param_type);
1466 plen = ntohs(phdr->param_length);
1467
1468 if ((plen == 0) || (offset + plen > length))
1469 break;
1470
1471 if (ptype == SCTP_RANDOM) {
1472 if (plen > sizeof(random_store))
1473 break;
1474 phdr = sctp_get_next_param(m, offset,
1475 (struct sctp_paramhdr *)random_store, min(plen, sizeof(random_store)));
1476 if (phdr == NULL)
1477 return;
1478 /* save the random and length for the key */
1479 p_random = (struct sctp_auth_random *)phdr;
1480 random_len = plen - sizeof(*p_random);
1481 } else if (ptype == SCTP_HMAC_LIST) {
1482 int num_hmacs;
1483 int i;
1484
1485 if (plen > sizeof(hmacs_store))
1486 break;
1487 phdr = sctp_get_next_param(m, offset,
1488 (struct sctp_paramhdr *)hmacs_store, min(plen,sizeof(hmacs_store)));
1489 if (phdr == NULL)
1490 return;
1491 /* save the hmacs list and num for the key */
1492 hmacs = (struct sctp_auth_hmac_algo *)phdr;
1493 hmacs_len = plen - sizeof(*hmacs);
1494 num_hmacs = hmacs_len / sizeof(hmacs->hmac_ids[0]);
1495 if (stcb->asoc.local_hmacs != NULL)
1496 sctp_free_hmaclist(stcb->asoc.local_hmacs);
1497 stcb->asoc.local_hmacs = sctp_alloc_hmaclist(num_hmacs);
1498 if (stcb->asoc.local_hmacs != NULL) {
1499 for (i = 0; i < num_hmacs; i++) {
1500 (void)sctp_auth_add_hmacid(stcb->asoc.local_hmacs,
1501 ntohs(hmacs->hmac_ids[i]));
1502 }
1503 }
1504 } else if (ptype == SCTP_CHUNK_LIST) {
1505 int i;
1506
1507 if (plen > sizeof(chunks_store))
1508 break;
1509 phdr = sctp_get_next_param(m, offset,
1510 (struct sctp_paramhdr *)chunks_store, min(plen,sizeof(chunks_store)));
1511 if (phdr == NULL)
1512 return;
1513 chunks = (struct sctp_auth_chunk_list *)phdr;
1514 num_chunks = plen - sizeof(*chunks);
1515 /* save chunks list and num for the key */
1516 if (stcb->asoc.local_auth_chunks != NULL)
1517 sctp_clear_chunklist(stcb->asoc.local_auth_chunks);
1518 else
1519 stcb->asoc.local_auth_chunks = sctp_alloc_chunklist();
1520 for (i = 0; i < num_chunks; i++) {
1521 (void)sctp_auth_add_chunk(chunks->chunk_types[i],
1522 stcb->asoc.local_auth_chunks);
1523 }
1524 }
1525 /* get next parameter */
1526 offset += SCTP_SIZE32(plen);
1527 if (offset + sizeof(struct sctp_paramhdr) > length)
1528 break;
1529 phdr = (struct sctp_paramhdr *)sctp_m_getptr(m, offset, sizeof(struct sctp_paramhdr),
1530 (uint8_t *)&tmp_param);
1531 }
1532 /* concatenate the full random key */
1533 keylen = sizeof(*p_random) + random_len + sizeof(*hmacs) + hmacs_len;
1534 if (chunks != NULL) {
1535 keylen += sizeof(*chunks) + num_chunks;
1536 }
1537 new_key = sctp_alloc_key(keylen);
1538 if (new_key != NULL) {
1539 /* copy in the RANDOM */
1540 if (p_random != NULL) {
1541 keylen = sizeof(*p_random) + random_len;
1542 bcopy(p_random, new_key->key, keylen);
1543 }
1544 /* append in the AUTH chunks */
1545 if (chunks != NULL) {
1546 bcopy(chunks, new_key->key + keylen,
1547 sizeof(*chunks) + num_chunks);
1548 keylen += sizeof(*chunks) + num_chunks;
1549 }
1550 /* append in the HMACs */
1551 if (hmacs != NULL) {
1552 bcopy(hmacs, new_key->key + keylen,
1553 sizeof(*hmacs) + hmacs_len);
1554 }
1555 }
1556 if (stcb->asoc.authinfo.random != NULL)
1557 sctp_free_key(stcb->asoc.authinfo.random);
1558 stcb->asoc.authinfo.random = new_key;
1559 stcb->asoc.authinfo.random_len = random_len;
1560 sctp_clear_cachedkeys(stcb, stcb->asoc.authinfo.assoc_keyid);
1561 sctp_clear_cachedkeys(stcb, stcb->asoc.authinfo.recv_keyid);
1562
1563 /* negotiate what HMAC to use for the peer */
1564 stcb->asoc.peer_hmac_id = sctp_negotiate_hmacid(stcb->asoc.peer_hmacs,
1565 stcb->asoc.local_hmacs);
1566
1567 /* copy defaults from the endpoint */
1568 /* FIX ME: put in cookie? */
1569 stcb->asoc.authinfo.active_keyid = stcb->sctp_ep->sctp_ep.default_keyid;
1570 /* copy out the shared key list (by reference) from the endpoint */
1571 (void)sctp_copy_skeylist(&stcb->sctp_ep->sctp_ep.shared_keys,
1572 &stcb->asoc.shared_keys);
1573 }
1574
1575 /*
1576 * compute and fill in the HMAC digest for a packet
1577 */
1578 void
1579 sctp_fill_hmac_digest_m(struct mbuf *m, uint32_t auth_offset,
1580 struct sctp_auth_chunk *auth, struct sctp_tcb *stcb, uint16_t keyid)
1581 {
1582 uint32_t digestlen;
1583 sctp_sharedkey_t *skey;
1584 sctp_key_t *key;
1585
1586 if ((stcb == NULL) || (auth == NULL))
1587 return;
1588
1589 /* zero the digest + chunk padding */
1590 digestlen = sctp_get_hmac_digest_len(stcb->asoc.peer_hmac_id);
1591 bzero(auth->hmac, SCTP_SIZE32(digestlen));
1592
1593 /* is the desired key cached? */
1594 if ((keyid != stcb->asoc.authinfo.assoc_keyid) ||
1595 (stcb->asoc.authinfo.assoc_key == NULL)) {
1596 if (stcb->asoc.authinfo.assoc_key != NULL) {
1597 /* free the old cached key */
1598 sctp_free_key(stcb->asoc.authinfo.assoc_key);
1599 }
1600 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
1601 /* the only way skey is NULL is if null key id 0 is used */
1602 if (skey != NULL)
1603 key = skey->key;
1604 else
1605 key = NULL;
1606 /* compute a new assoc key and cache it */
1607 stcb->asoc.authinfo.assoc_key =
1608 sctp_compute_hashkey(stcb->asoc.authinfo.random,
1609 stcb->asoc.authinfo.peer_random, key);
1610 stcb->asoc.authinfo.assoc_keyid = keyid;
1611 SCTPDBG(SCTP_DEBUG_AUTH1, "caching key id %u\n",
1612 stcb->asoc.authinfo.assoc_keyid);
1613 #ifdef SCTP_DEBUG
1614 if (SCTP_AUTH_DEBUG)
1615 sctp_print_key(stcb->asoc.authinfo.assoc_key,
1616 "Assoc Key");
1617 #endif
1618 }
1619
1620 /* set in the active key id */
1621 auth->shared_key_id = htons(keyid);
1622
1623 /* compute and fill in the digest */
1624 (void)sctp_compute_hmac_m(stcb->asoc.peer_hmac_id, stcb->asoc.authinfo.assoc_key,
1625 m, auth_offset, auth->hmac);
1626 }
1627
1628
1629 static void
1630 sctp_bzero_m(struct mbuf *m, uint32_t m_offset, uint32_t size)
1631 {
1632 struct mbuf *m_tmp;
1633 uint8_t *data;
1634
1635 /* sanity check */
1636 if (m == NULL)
1637 return;
1638
1639 /* find the correct starting mbuf and offset (get start position) */
1640 m_tmp = m;
1641 while ((m_tmp != NULL) && (m_offset >= (uint32_t) SCTP_BUF_LEN(m_tmp))) {
1642 m_offset -= SCTP_BUF_LEN(m_tmp);
1643 m_tmp = SCTP_BUF_NEXT(m_tmp);
1644 }
1645 /* now use the rest of the mbuf chain */
1646 while ((m_tmp != NULL) && (size > 0)) {
1647 data = mtod(m_tmp, uint8_t *) + m_offset;
1648 if (size > (uint32_t) SCTP_BUF_LEN(m_tmp)) {
1649 bzero(data, SCTP_BUF_LEN(m_tmp));
1650 size -= SCTP_BUF_LEN(m_tmp);
1651 } else {
1652 bzero(data, size);
1653 size = 0;
1654 }
1655 /* clear the offset since it's only for the first mbuf */
1656 m_offset = 0;
1657 m_tmp = SCTP_BUF_NEXT(m_tmp);
1658 }
1659 }
1660
1661 /*-
1662 * process the incoming Authentication chunk
1663 * return codes:
1664 * -1 on any authentication error
1665 * 0 on authentication verification
1666 */
1667 int
1668 sctp_handle_auth(struct sctp_tcb *stcb, struct sctp_auth_chunk *auth,
1669 struct mbuf *m, uint32_t offset)
1670 {
1671 uint16_t chunklen;
1672 uint16_t shared_key_id;
1673 uint16_t hmac_id;
1674 sctp_sharedkey_t *skey;
1675 uint32_t digestlen;
1676 uint8_t digest[SCTP_AUTH_DIGEST_LEN_MAX];
1677 uint8_t computed_digest[SCTP_AUTH_DIGEST_LEN_MAX];
1678
1679 /* auth is checked for NULL by caller */
1680 chunklen = ntohs(auth->ch.chunk_length);
1681 if (chunklen < sizeof(*auth)) {
1682 SCTP_STAT_INCR(sctps_recvauthfailed);
1683 return (-1);
1684 }
1685 SCTP_STAT_INCR(sctps_recvauth);
1686
1687 /* get the auth params */
1688 shared_key_id = ntohs(auth->shared_key_id);
1689 hmac_id = ntohs(auth->hmac_id);
1690 SCTPDBG(SCTP_DEBUG_AUTH1,
1691 "SCTP AUTH Chunk: shared key %u, HMAC id %u\n",
1692 shared_key_id, hmac_id);
1693
1694 /* is the indicated HMAC supported? */
1695 if (!sctp_auth_is_supported_hmac(stcb->asoc.local_hmacs, hmac_id)) {
1696 struct mbuf *m_err;
1697 struct sctp_auth_invalid_hmac *err;
1698
1699 SCTP_STAT_INCR(sctps_recvivalhmacid);
1700 SCTPDBG(SCTP_DEBUG_AUTH1,
1701 "SCTP Auth: unsupported HMAC id %u\n",
1702 hmac_id);
1703 /*
1704 * report this in an Error Chunk: Unsupported HMAC
1705 * Identifier
1706 */
1707 m_err = sctp_get_mbuf_for_msg(sizeof(*err), 0, M_NOWAIT,
1708 1, MT_HEADER);
1709 if (m_err != NULL) {
1710 /* pre-reserve some space */
1711 SCTP_BUF_RESV_UF(m_err, sizeof(struct sctp_chunkhdr));
1712 /* fill in the error */
1713 err = mtod(m_err, struct sctp_auth_invalid_hmac *);
1714 bzero(err, sizeof(*err));
1715 err->ph.param_type = htons(SCTP_CAUSE_UNSUPPORTED_HMACID);
1716 err->ph.param_length = htons(sizeof(*err));
1717 err->hmac_id = ntohs(hmac_id);
1718 SCTP_BUF_LEN(m_err) = sizeof(*err);
1719 /* queue it */
1720 sctp_queue_op_err(stcb, m_err);
1721 }
1722 return (-1);
1723 }
1724 /* get the indicated shared key, if available */
1725 if ((stcb->asoc.authinfo.recv_key == NULL) ||
1726 (stcb->asoc.authinfo.recv_keyid != shared_key_id)) {
1727 /* find the shared key on the assoc first */
1728 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys,
1729 shared_key_id);
1730 /* if the shared key isn't found, discard the chunk */
1731 if (skey == NULL) {
1732 SCTP_STAT_INCR(sctps_recvivalkeyid);
1733 SCTPDBG(SCTP_DEBUG_AUTH1,
1734 "SCTP Auth: unknown key id %u\n",
1735 shared_key_id);
1736 return (-1);
1737 }
1738 /* generate a notification if this is a new key id */
1739 if (stcb->asoc.authinfo.recv_keyid != shared_key_id)
1740 /*
1741 * sctp_ulp_notify(SCTP_NOTIFY_AUTH_NEW_KEY, stcb,
1742 * shared_key_id, (void
1743 * *)stcb->asoc.authinfo.recv_keyid);
1744 */
1745 sctp_notify_authentication(stcb, SCTP_AUTH_NEW_KEY,
1746 shared_key_id, stcb->asoc.authinfo.recv_keyid,
1747 SCTP_SO_NOT_LOCKED);
1748 /* compute a new recv assoc key and cache it */
1749 if (stcb->asoc.authinfo.recv_key != NULL)
1750 sctp_free_key(stcb->asoc.authinfo.recv_key);
1751 stcb->asoc.authinfo.recv_key =
1752 sctp_compute_hashkey(stcb->asoc.authinfo.random,
1753 stcb->asoc.authinfo.peer_random, skey->key);
1754 stcb->asoc.authinfo.recv_keyid = shared_key_id;
1755 #ifdef SCTP_DEBUG
1756 if (SCTP_AUTH_DEBUG)
1757 sctp_print_key(stcb->asoc.authinfo.recv_key, "Recv Key");
1758 #endif
1759 }
1760 /* validate the digest length */
1761 digestlen = sctp_get_hmac_digest_len(hmac_id);
1762 if (chunklen < (sizeof(*auth) + digestlen)) {
1763 /* invalid digest length */
1764 SCTP_STAT_INCR(sctps_recvauthfailed);
1765 SCTPDBG(SCTP_DEBUG_AUTH1,
1766 "SCTP Auth: chunk too short for HMAC\n");
1767 return (-1);
1768 }
1769 /* save a copy of the digest, zero the pseudo header, and validate */
1770 bcopy(auth->hmac, digest, digestlen);
1771 sctp_bzero_m(m, offset + sizeof(*auth), SCTP_SIZE32(digestlen));
1772 (void)sctp_compute_hmac_m(hmac_id, stcb->asoc.authinfo.recv_key,
1773 m, offset, computed_digest);
1774
1775 /* compare the computed digest with the one in the AUTH chunk */
1776 if (memcmp(digest, computed_digest, digestlen) != 0) {
1777 SCTP_STAT_INCR(sctps_recvauthfailed);
1778 SCTPDBG(SCTP_DEBUG_AUTH1,
1779 "SCTP Auth: HMAC digest check failed\n");
1780 return (-1);
1781 }
1782 return (0);
1783 }
1784
1785 /*
1786 * Generate NOTIFICATION
1787 */
1788 void
1789 sctp_notify_authentication(struct sctp_tcb *stcb, uint32_t indication,
1790 uint16_t keyid, uint16_t alt_keyid, int so_locked
1791 #if !defined(__APPLE__) && !defined(SCTP_SO_LOCK_TESTING)
1792 SCTP_UNUSED
1793 #endif
1794 )
1795 {
1796 struct mbuf *m_notify;
1797 struct sctp_authkey_event *auth;
1798 struct sctp_queued_to_read *control;
1799
1800 if ((stcb == NULL) ||
1801 (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) ||
1802 (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_ALLGONE) ||
1803 (stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET)
1804 ) {
1805 /* If the socket is gone we are out of here */
1806 return;
1807 }
1808
1809 if (sctp_stcb_is_feature_off(stcb->sctp_ep, stcb, SCTP_PCB_FLAGS_AUTHEVNT))
1810 /* event not enabled */
1811 return;
1812
1813 m_notify = sctp_get_mbuf_for_msg(sizeof(struct sctp_authkey_event),
1814 0, M_NOWAIT, 1, MT_HEADER);
1815 if (m_notify == NULL)
1816 /* no space left */
1817 return;
1818
1819 SCTP_BUF_LEN(m_notify) = 0;
1820 auth = mtod(m_notify, struct sctp_authkey_event *);
1821 auth->auth_type = SCTP_AUTHENTICATION_EVENT;
1822 auth->auth_flags = 0;
1823 auth->auth_length = sizeof(*auth);
1824 auth->auth_keynumber = keyid;
1825 auth->auth_altkeynumber = alt_keyid;
1826 auth->auth_indication = indication;
1827 auth->auth_assoc_id = sctp_get_associd(stcb);
1828
1829 SCTP_BUF_LEN(m_notify) = sizeof(*auth);
1830 SCTP_BUF_NEXT(m_notify) = NULL;
1831
1832 /* append to socket */
1833 control = sctp_build_readq_entry(stcb, stcb->asoc.primary_destination,
1834 0, 0, stcb->asoc.context, 0, 0, 0, m_notify);
1835 if (control == NULL) {
1836 /* no memory */
1837 sctp_m_freem(m_notify);
1838 return;
1839 }
1840 control->spec_flags = M_NOTIFICATION;
1841 control->length = SCTP_BUF_LEN(m_notify);
1842 /* not that we need this */
1843 control->tail_mbuf = m_notify;
1844 sctp_add_to_readq(stcb->sctp_ep, stcb, control,
1845 &stcb->sctp_socket->so_rcv, 1, SCTP_READ_LOCK_NOT_HELD, so_locked);
1846 }
1847
1848
1849 /*-
1850 * validates the AUTHentication related parameters in an INIT/INIT-ACK
1851 * Note: currently only used for INIT as INIT-ACK is handled inline
1852 * with sctp_load_addresses_from_init()
1853 */
1854 int
1855 sctp_validate_init_auth_params(struct mbuf *m, int offset, int limit)
1856 {
1857 struct sctp_paramhdr *phdr, parm_buf;
1858 uint16_t ptype, plen;
1859 int peer_supports_asconf = 0;
1860 int peer_supports_auth = 0;
1861 int got_random = 0, got_hmacs = 0, got_chklist = 0;
1862 uint8_t saw_asconf = 0;
1863 uint8_t saw_asconf_ack = 0;
1864
1865 /* go through each of the params. */
1866 phdr = sctp_get_next_param(m, offset, &parm_buf, sizeof(parm_buf));
1867 while (phdr) {
1868 ptype = ntohs(phdr->param_type);
1869 plen = ntohs(phdr->param_length);
1870
1871 if (offset + plen > limit) {
1872 break;
1873 }
1874 if (plen < sizeof(struct sctp_paramhdr)) {
1875 break;
1876 }
1877 if (ptype == SCTP_SUPPORTED_CHUNK_EXT) {
1878 /* A supported extension chunk */
1879 struct sctp_supported_chunk_types_param *pr_supported;
1880 uint8_t local_store[SCTP_PARAM_BUFFER_SIZE];
1881 int num_ent, i;
1882
1883 phdr = sctp_get_next_param(m, offset,
1884 (struct sctp_paramhdr *)&local_store, min(plen,sizeof(local_store)));
1885 if (phdr == NULL) {
1886 return (-1);
1887 }
1888 pr_supported = (struct sctp_supported_chunk_types_param *)phdr;
1889 num_ent = plen - sizeof(struct sctp_paramhdr);
1890 for (i = 0; i < num_ent; i++) {
1891 switch (pr_supported->chunk_types[i]) {
1892 case SCTP_ASCONF:
1893 case SCTP_ASCONF_ACK:
1894 peer_supports_asconf = 1;
1895 break;
1896 default:
1897 /* one we don't care about */
1898 break;
1899 }
1900 }
1901 } else if (ptype == SCTP_RANDOM) {
1902 got_random = 1;
1903 /* enforce the random length */
1904 if (plen != (sizeof(struct sctp_auth_random) +
1905 SCTP_AUTH_RANDOM_SIZE_REQUIRED)) {
1906 SCTPDBG(SCTP_DEBUG_AUTH1,
1907 "SCTP: invalid RANDOM len\n");
1908 return (-1);
1909 }
1910 } else if (ptype == SCTP_HMAC_LIST) {
1911 uint8_t store[SCTP_PARAM_BUFFER_SIZE];
1912 struct sctp_auth_hmac_algo *hmacs;
1913 int num_hmacs;
1914
1915 if (plen > sizeof(store))
1916 break;
1917 phdr = sctp_get_next_param(m, offset,
1918 (struct sctp_paramhdr *)store, min(plen,sizeof(store)));
1919 if (phdr == NULL)
1920 return (-1);
1921 hmacs = (struct sctp_auth_hmac_algo *)phdr;
1922 num_hmacs = (plen - sizeof(*hmacs)) /
1923 sizeof(hmacs->hmac_ids[0]);
1924 /* validate the hmac list */
1925 if (sctp_verify_hmac_param(hmacs, num_hmacs)) {
1926 SCTPDBG(SCTP_DEBUG_AUTH1,
1927 "SCTP: invalid HMAC param\n");
1928 return (-1);
1929 }
1930 got_hmacs = 1;
1931 } else if (ptype == SCTP_CHUNK_LIST) {
1932 int i, num_chunks;
1933 uint8_t chunks_store[SCTP_SMALL_CHUNK_STORE];
1934 /* did the peer send a non-empty chunk list? */
1935 struct sctp_auth_chunk_list *chunks = NULL;
1936 phdr = sctp_get_next_param(m, offset,
1937 (struct sctp_paramhdr *)chunks_store,
1938 min(plen,sizeof(chunks_store)));
1939 if (phdr == NULL)
1940 return (-1);
1941
1942 /*-
1943 * Flip through the list and mark that the
1944 * peer supports asconf/asconf_ack.
1945 */
1946 chunks = (struct sctp_auth_chunk_list *)phdr;
1947 num_chunks = plen - sizeof(*chunks);
1948 for (i = 0; i < num_chunks; i++) {
1949 /* record asconf/asconf-ack if listed */
1950 if (chunks->chunk_types[i] == SCTP_ASCONF)
1951 saw_asconf = 1;
1952 if (chunks->chunk_types[i] == SCTP_ASCONF_ACK)
1953 saw_asconf_ack = 1;
1954
1955 }
1956 if (num_chunks)
1957 got_chklist = 1;
1958 }
1959
1960 offset += SCTP_SIZE32(plen);
1961 if (offset >= limit) {
1962 break;
1963 }
1964 phdr = sctp_get_next_param(m, offset, &parm_buf,
1965 sizeof(parm_buf));
1966 }
1967 /* validate authentication required parameters */
1968 if (got_random && got_hmacs) {
1969 peer_supports_auth = 1;
1970 } else {
1971 peer_supports_auth = 0;
1972 }
1973 if (!peer_supports_auth && got_chklist) {
1974 SCTPDBG(SCTP_DEBUG_AUTH1,
1975 "SCTP: peer sent chunk list w/o AUTH\n");
1976 return (-1);
1977 }
1978 if (!SCTP_BASE_SYSCTL(sctp_asconf_auth_nochk) && peer_supports_asconf &&
1979 !peer_supports_auth) {
1980 SCTPDBG(SCTP_DEBUG_AUTH1,
1981 "SCTP: peer supports ASCONF but not AUTH\n");
1982 return (-1);
1983 } else if ((peer_supports_asconf) && (peer_supports_auth) &&
1984 ((saw_asconf == 0) || (saw_asconf_ack == 0))) {
1985 return (-2);
1986 }
1987 return (0);
1988 }
1989
1990 void
1991 sctp_initialize_auth_params(struct sctp_inpcb *inp, struct sctp_tcb *stcb)
1992 {
1993 uint16_t chunks_len = 0;
1994 uint16_t hmacs_len = 0;
1995 uint16_t random_len = SCTP_AUTH_RANDOM_SIZE_DEFAULT;
1996 sctp_key_t *new_key;
1997 uint16_t keylen;
1998
1999 /* initialize hmac list from endpoint */
2000 stcb->asoc.local_hmacs = sctp_copy_hmaclist(inp->sctp_ep.local_hmacs);
2001 if (stcb->asoc.local_hmacs != NULL) {
2002 hmacs_len = stcb->asoc.local_hmacs->num_algo *
2003 sizeof(stcb->asoc.local_hmacs->hmac[0]);
2004 }
2005 /* initialize auth chunks list from endpoint */
2006 stcb->asoc.local_auth_chunks =
2007 sctp_copy_chunklist(inp->sctp_ep.local_auth_chunks);
2008 if (stcb->asoc.local_auth_chunks != NULL) {
2009 int i;
2010 for (i = 0; i < 256; i++) {
2011 if (stcb->asoc.local_auth_chunks->chunks[i])
2012 chunks_len++;
2013 }
2014 }
2015 /* copy defaults from the endpoint */
2016 stcb->asoc.authinfo.active_keyid = inp->sctp_ep.default_keyid;
2017
2018 /* copy out the shared key list (by reference) from the endpoint */
2019 (void)sctp_copy_skeylist(&inp->sctp_ep.shared_keys,
2020 &stcb->asoc.shared_keys);
2021
2022 /* now set the concatenated key (random + chunks + hmacs) */
2023 /* key includes parameter headers */
2024 keylen = (3 * sizeof(struct sctp_paramhdr)) + random_len + chunks_len +
2025 hmacs_len;
2026 new_key = sctp_alloc_key(keylen);
2027 if (new_key != NULL) {
2028 struct sctp_paramhdr *ph;
2029 int plen;
2030 /* generate and copy in the RANDOM */
2031 ph = (struct sctp_paramhdr *)new_key->key;
2032 ph->param_type = htons(SCTP_RANDOM);
2033 plen = sizeof(*ph) + random_len;
2034 ph->param_length = htons(plen);
2035 SCTP_READ_RANDOM(new_key->key + sizeof(*ph), random_len);
2036 keylen = plen;
2037
2038 /* append in the AUTH chunks */
2039 /* NOTE: currently we always have chunks to list */
2040 ph = (struct sctp_paramhdr *)(new_key->key + keylen);
2041 ph->param_type = htons(SCTP_CHUNK_LIST);
2042 plen = sizeof(*ph) + chunks_len;
2043 ph->param_length = htons(plen);
2044 keylen += sizeof(*ph);
2045 if (stcb->asoc.local_auth_chunks) {
2046 int i;
2047 for (i = 0; i < 256; i++) {
2048 if (stcb->asoc.local_auth_chunks->chunks[i])
2049 new_key->key[keylen++] = i;
2050 }
2051 }
2052
2053 /* append in the HMACs */
2054 ph = (struct sctp_paramhdr *)(new_key->key + keylen);
2055 ph->param_type = htons(SCTP_HMAC_LIST);
2056 plen = sizeof(*ph) + hmacs_len;
2057 ph->param_length = htons(plen);
2058 keylen += sizeof(*ph);
2059 (void)sctp_serialize_hmaclist(stcb->asoc.local_hmacs,
2060 new_key->key + keylen);
2061 }
2062 if (stcb->asoc.authinfo.random != NULL)
2063 sctp_free_key(stcb->asoc.authinfo.random);
2064 stcb->asoc.authinfo.random = new_key;
2065 stcb->asoc.authinfo.random_len = random_len;
2066 }
2067
2068
2069 #ifdef SCTP_HMAC_TEST
2070 /*
2071 * HMAC and key concatenation tests
2072 */
2073 static void
2074 sctp_print_digest(uint8_t *digest, uint32_t digestlen, const char *str)
2075 {
2076 uint32_t i;
2077
2078 SCTP_PRINTF("\n%s: 0x", str);
2079 if (digest == NULL)
2080 return;
2081
2082 for (i = 0; i < digestlen; i++)
2083 SCTP_PRINTF("%02x", digest[i]);
2084 }
2085
2086 static int
2087 sctp_test_hmac(const char *str, uint16_t hmac_id, uint8_t *key,
2088 uint32_t keylen, uint8_t *text, uint32_t textlen,
2089 uint8_t *digest, uint32_t digestlen)
2090 {
2091 uint8_t computed_digest[SCTP_AUTH_DIGEST_LEN_MAX];
2092
2093 SCTP_PRINTF("\n%s:", str);
2094 sctp_hmac(hmac_id, key, keylen, text, textlen, computed_digest);
2095 sctp_print_digest(digest, digestlen, "Expected digest");
2096 sctp_print_digest(computed_digest, digestlen, "Computed digest");
2097 if (memcmp(digest, computed_digest, digestlen) != 0) {
2098 SCTP_PRINTF("\nFAILED");
2099 return (-1);
2100 } else {
2101 SCTP_PRINTF("\nPASSED");
2102 return (0);
2103 }
2104 }
2105
2106
2107 /*
2108 * RFC 2202: HMAC-SHA1 test cases
2109 */
2110 void
2111 sctp_test_hmac_sha1(void)
2112 {
2113 uint8_t *digest;
2114 uint8_t key[128];
2115 uint32_t keylen;
2116 uint8_t text[128];
2117 uint32_t textlen;
2118 uint32_t digestlen = 20;
2119 int failed = 0;
2120
2121 /*-
2122 * test_case = 1
2123 * key = 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b
2124 * key_len = 20
2125 * data = "Hi There"
2126 * data_len = 8
2127 * digest = 0xb617318655057264e28bc0b6fb378c8ef146be00
2128 */
2129 keylen = 20;
2130 memset(key, 0x0b, keylen);
2131 textlen = 8;
2132 strcpy(text, "Hi There");
2133 digest = "\xb6\x17\x31\x86\x55\x05\x72\x64\xe2\x8b\xc0\xb6\xfb\x37\x8c\x8e\xf1\x46\xbe\x00";
2134 if (sctp_test_hmac("SHA1 test case 1", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2135 text, textlen, digest, digestlen) < 0)
2136 failed++;
2137
2138 /*-
2139 * test_case = 2
2140 * key = "Jefe"
2141 * key_len = 4
2142 * data = "what do ya want for nothing?"
2143 * data_len = 28
2144 * digest = 0xeffcdf6ae5eb2fa2d27416d5f184df9c259a7c79
2145 */
2146 keylen = 4;
2147 strcpy(key, "Jefe");
2148 textlen = 28;
2149 strcpy(text, "what do ya want for nothing?");
2150 digest = "\xef\xfc\xdf\x6a\xe5\xeb\x2f\xa2\xd2\x74\x16\xd5\xf1\x84\xdf\x9c\x25\x9a\x7c\x79";
2151 if (sctp_test_hmac("SHA1 test case 2", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2152 text, textlen, digest, digestlen) < 0)
2153 failed++;
2154
2155 /*-
2156 * test_case = 3
2157 * key = 0xaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
2158 * key_len = 20
2159 * data = 0xdd repeated 50 times
2160 * data_len = 50
2161 * digest = 0x125d7342b9ac11cd91a39af48aa17b4f63f175d3
2162 */
2163 keylen = 20;
2164 memset(key, 0xaa, keylen);
2165 textlen = 50;
2166 memset(text, 0xdd, textlen);
2167 digest = "\x12\x5d\x73\x42\xb9\xac\x11\xcd\x91\xa3\x9a\xf4\x8a\xa1\x7b\x4f\x63\xf1\x75\xd3";
2168 if (sctp_test_hmac("SHA1 test case 3", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2169 text, textlen, digest, digestlen) < 0)
2170 failed++;
2171
2172 /*-
2173 * test_case = 4
2174 * key = 0x0102030405060708090a0b0c0d0e0f10111213141516171819
2175 * key_len = 25
2176 * data = 0xcd repeated 50 times
2177 * data_len = 50
2178 * digest = 0x4c9007f4026250c6bc8414f9bf50c86c2d7235da
2179 */
2180 keylen = 25;
2181 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);
2182 textlen = 50;
2183 memset(text, 0xcd, textlen);
2184 digest = "\x4c\x90\x07\xf4\x02\x62\x50\xc6\xbc\x84\x14\xf9\xbf\x50\xc8\x6c\x2d\x72\x35\xda";
2185 if (sctp_test_hmac("SHA1 test case 4", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2186 text, textlen, digest, digestlen) < 0)
2187 failed++;
2188
2189 /*-
2190 * test_case = 5
2191 * key = 0x0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c0c
2192 * key_len = 20
2193 * data = "Test With Truncation"
2194 * data_len = 20
2195 * digest = 0x4c1a03424b55e07fe7f27be1d58bb9324a9a5a04
2196 * digest-96 = 0x4c1a03424b55e07fe7f27be1
2197 */
2198 keylen = 20;
2199 memset(key, 0x0c, keylen);
2200 textlen = 20;
2201 strcpy(text, "Test With Truncation");
2202 digest = "\x4c\x1a\x03\x42\x4b\x55\xe0\x7f\xe7\xf2\x7b\xe1\xd5\x8b\xb9\x32\x4a\x9a\x5a\x04";
2203 if (sctp_test_hmac("SHA1 test case 5", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2204 text, textlen, digest, digestlen) < 0)
2205 failed++;
2206
2207 /*-
2208 * test_case = 6
2209 * key = 0xaa repeated 80 times
2210 * key_len = 80
2211 * data = "Test Using Larger Than Block-Size Key - Hash Key First"
2212 * data_len = 54
2213 * digest = 0xaa4ae5e15272d00e95705637ce8a3b55ed402112
2214 */
2215 keylen = 80;
2216 memset(key, 0xaa, keylen);
2217 textlen = 54;
2218 strcpy(text, "Test Using Larger Than Block-Size Key - Hash Key First");
2219 digest = "\xaa\x4a\xe5\xe1\x52\x72\xd0\x0e\x95\x70\x56\x37\xce\x8a\x3b\x55\xed\x40\x21\x12";
2220 if (sctp_test_hmac("SHA1 test case 6", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2221 text, textlen, digest, digestlen) < 0)
2222 failed++;
2223
2224 /*-
2225 * test_case = 7
2226 * key = 0xaa repeated 80 times
2227 * key_len = 80
2228 * data = "Test Using Larger Than Block-Size Key and Larger Than One Block-Size Data"
2229 * data_len = 73
2230 * digest = 0xe8e99d0f45237d786d6bbaa7965c7808bbff1a91
2231 */
2232 keylen = 80;
2233 memset(key, 0xaa, keylen);
2234 textlen = 73;
2235 strcpy(text, "Test Using Larger Than Block-Size Key and Larger Than One Block-Size Data");
2236 digest = "\xe8\xe9\x9d\x0f\x45\x23\x7d\x78\x6d\x6b\xba\xa7\x96\x5c\x78\x08\xbb\xff\x1a\x91";
2237 if (sctp_test_hmac("SHA1 test case 7", SCTP_AUTH_HMAC_ID_SHA1, key, keylen,
2238 text, textlen, digest, digestlen) < 0)
2239 failed++;
2240
2241 /* done with all tests */
2242 if (failed)
2243 SCTP_PRINTF("\nSHA1 test results: %d cases failed", failed);
2244 else
2245 SCTP_PRINTF("\nSHA1 test results: all test cases passed");
2246 }
2247
2248 /*
2249 * test assoc key concatenation
2250 */
2251 static int
2252 sctp_test_key_concatenation(sctp_key_t *key1, sctp_key_t *key2,
2253 sctp_key_t *expected_key)
2254 {
2255 sctp_key_t *key;
2256 int ret_val;
2257
2258 sctp_show_key(key1, "\nkey1");
2259 sctp_show_key(key2, "\nkey2");
2260 key = sctp_compute_hashkey(key1, key2, NULL);
2261 sctp_show_key(expected_key, "\nExpected");
2262 sctp_show_key(key, "\nComputed");
2263 if (memcmp(key, expected_key, expected_key->keylen) != 0) {
2264 SCTP_PRINTF("\nFAILED");
2265 ret_val = -1;
2266 } else {
2267 SCTP_PRINTF("\nPASSED");
2268 ret_val = 0;
2269 }
2270 sctp_free_key(key1);
2271 sctp_free_key(key2);
2272 sctp_free_key(expected_key);
2273 sctp_free_key(key);
2274 return (ret_val);
2275 }
2276
2277
2278 void
2279 sctp_test_authkey(void)
2280 {
2281 sctp_key_t *key1, *key2, *expected_key;
2282 int failed = 0;
2283
2284 /* test case 1 */
2285 key1 = sctp_set_key("\x01\x01\x01\x01", 4);
2286 key2 = sctp_set_key("\x01\x02\x03\x04", 4);
2287 expected_key = sctp_set_key("\x01\x01\x01\x01\x01\x02\x03\x04", 8);
2288 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2289 failed++;
2290
2291 /* test case 2 */
2292 key1 = sctp_set_key("\x00\x00\x00\x01", 4);
2293 key2 = sctp_set_key("\x02", 1);
2294 expected_key = sctp_set_key("\x00\x00\x00\x01\x02", 5);
2295 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2296 failed++;
2297
2298 /* test case 3 */
2299 key1 = sctp_set_key("\x01", 1);
2300 key2 = sctp_set_key("\x00\x00\x00\x02", 4);
2301 expected_key = sctp_set_key("\x01\x00\x00\x00\x02", 5);
2302 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2303 failed++;
2304
2305 /* test case 4 */
2306 key1 = sctp_set_key("\x00\x00\x00\x01", 4);
2307 key2 = sctp_set_key("\x01", 1);
2308 expected_key = sctp_set_key("\x01\x00\x00\x00\x01", 5);
2309 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2310 failed++;
2311
2312 /* test case 5 */
2313 key1 = sctp_set_key("\x01", 1);
2314 key2 = sctp_set_key("\x00\x00\x00\x01", 4);
2315 expected_key = sctp_set_key("\x01\x00\x00\x00\x01", 5);
2316 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2317 failed++;
2318
2319 /* test case 6 */
2320 key1 = sctp_set_key("\x00\x00\x00\x00\x01\x02\x03\x04\x05\x06\x07", 11);
2321 key2 = sctp_set_key("\x00\x00\x00\x00\x01\x02\x03\x04\x05\x06\x08", 11);
2322 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);
2323 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2324 failed++;
2325
2326 /* test case 7 */
2327 key1 = sctp_set_key("\x00\x00\x00\x00\x01\x02\x03\x04\x05\x06\x08", 11);
2328 key2 = sctp_set_key("\x00\x00\x00\x00\x01\x02\x03\x04\x05\x06\x07", 11);
2329 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);
2330 if (sctp_test_key_concatenation(key1, key2, expected_key) < 0)
2331 failed++;
2332
2333 /* done with all tests */
2334 if (failed)
2335 SCTP_PRINTF("\nKey concatenation test results: %d cases failed", failed);
2336 else
2337 SCTP_PRINTF("\nKey concatenation test results: all test cases passed");
2338 }
2339
2340
2341 #if defined(STANDALONE_HMAC_TEST)
2342 int
2343 main(void)
2344 {
2345 sctp_test_hmac_sha1();
2346 sctp_test_authkey();
2347 }
2348
2349 #endif /* STANDALONE_HMAC_TEST */
2350
2351 #endif /* SCTP_HMAC_TEST */
2352