sctp_auth.c

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    1 /*-
    2  * Copyright (c) 2001-2008, by Cisco Systems, Inc. All rights reserved.
    3  * Copyright (c) 2008-2012, by Randall Stewart. All rights reserved.
    4  * Copyright (c) 2008-2012, by Michael Tuexen. All rights reserved.
    5  *
    6  * Redistribution and use in source and binary forms, with or without
    7  * modification, are permitted provided that the following conditions are met:
    8  *
    9  * a) Redistributions of source code must retain the above copyright notice,
   10  *    this list of conditions and the following disclaimer.
   11  *
   12  * b) Redistributions in binary form must reproduce the above copyright
   13  *    notice, this list of conditions and the following disclaimer in
   14  *    the documentation and/or other materials provided with the distribution.
   15  *
   16  * c) Neither the name of Cisco Systems, Inc. nor the names of its
   17  *    contributors may be used to endorse or promote products derived
   18  *    from this software without specific prior written permission.
   19  *
   20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   21  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
   22  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   23  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
   24  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
   30  * THE POSSIBILITY OF SUCH DAMAGE.
   31  */
   32 
   33 #include <sys/cdefs.h>
   34 __FBSDID("$FreeBSD: releng/11.1/sys/netinet/sctp_auth.c 320457 2017-06-28 21:08:21Z tuexen $");
   35 
   36 #include <netinet/sctp_os.h>
   37 #include <netinet/sctp.h>
   38 #include <netinet/sctp_header.h>
   39 #include <netinet/sctp_pcb.h>
   40 #include <netinet/sctp_var.h>
   41 #include <netinet/sctp_sysctl.h>
   42 #include <netinet/sctputil.h>
   43 #include <netinet/sctp_indata.h>
   44 #include <netinet/sctp_output.h>
   45 #include <netinet/sctp_auth.h>
   46 
   47 #ifdef SCTP_DEBUG
   48 #define SCTP_AUTH_DEBUG         (SCTP_BASE_SYSCTL(sctp_debug_on) & SCTP_DEBUG_AUTH1)
   49 #define SCTP_AUTH_DEBUG2        (SCTP_BASE_SYSCTL(sctp_debug_on) & SCTP_DEBUG_AUTH2)
   50 #endif                          /* SCTP_DEBUG */
   51 
   52 
   53 void
   54 sctp_clear_chunklist(sctp_auth_chklist_t *chklist)
   55 {
   56         bzero(chklist, sizeof(*chklist));
   57         /* chklist->num_chunks = 0; */
   58 }
   59 
   60 sctp_auth_chklist_t *
   61 sctp_alloc_chunklist(void)
   62 {
   63         sctp_auth_chklist_t *chklist;
   64 
   65         SCTP_MALLOC(chklist, sctp_auth_chklist_t *, sizeof(*chklist),
   66             SCTP_M_AUTH_CL);
   67         if (chklist == NULL) {
   68                 SCTPDBG(SCTP_DEBUG_AUTH1, "sctp_alloc_chunklist: failed to get memory!\n");
   69         } else {
   70                 sctp_clear_chunklist(chklist);
   71         }
   72         return (chklist);
   73 }
   74 
   75 void
   76 sctp_free_chunklist(sctp_auth_chklist_t *list)
   77 {
   78         if (list != NULL)
   79                 SCTP_FREE(list, SCTP_M_AUTH_CL);
   80 }
   81 
   82 sctp_auth_chklist_t *
   83 sctp_copy_chunklist(sctp_auth_chklist_t *list)
   84 {
   85         sctp_auth_chklist_t *new_list;
   86 
   87         if (list == NULL)
   88                 return (NULL);
   89 
   90         /* get a new list */
   91         new_list = sctp_alloc_chunklist();
   92         if (new_list == NULL)
   93                 return (NULL);
   94         /* copy it */
   95         bcopy(list, new_list, sizeof(*new_list));
   96 
   97         return (new_list);
   98 }
   99 
  100 
  101 /*
  102  * add a chunk to the required chunks list
  103  */
  104 int
  105 sctp_auth_add_chunk(uint8_t chunk, sctp_auth_chklist_t *list)
  106 {
  107         if (list == NULL)
  108                 return (-1);
  109 
  110         /* is chunk restricted? */
  111         if ((chunk == SCTP_INITIATION) ||
  112             (chunk == SCTP_INITIATION_ACK) ||
  113             (chunk == SCTP_SHUTDOWN_COMPLETE) ||
  114             (chunk == SCTP_AUTHENTICATION)) {
  115                 return (-1);
  116         }
  117         if (list->chunks[chunk] == 0) {
  118                 list->chunks[chunk] = 1;
  119                 list->num_chunks++;
  120                 SCTPDBG(SCTP_DEBUG_AUTH1,
  121                     "SCTP: added chunk %u (0x%02x) to Auth list\n",
  122                     chunk, chunk);
  123         }
  124         return (0);
  125 }
  126 
  127 /*
  128  * delete a chunk from the required chunks list
  129  */
  130 int
  131 sctp_auth_delete_chunk(uint8_t chunk, sctp_auth_chklist_t *list)
  132 {
  133         if (list == NULL)
  134                 return (-1);
  135 
  136         if (list->chunks[chunk] == 1) {
  137                 list->chunks[chunk] = 0;
  138                 list->num_chunks--;
  139                 SCTPDBG(SCTP_DEBUG_AUTH1,
  140                     "SCTP: deleted chunk %u (0x%02x) from Auth list\n",
  141                     chunk, chunk);
  142         }
  143         return (0);
  144 }
  145 
  146 size_t
  147 sctp_auth_get_chklist_size(const sctp_auth_chklist_t *list)
  148 {
  149         if (list == NULL)
  150                 return (0);
  151         else
  152                 return (list->num_chunks);
  153 }
  154 
  155 /*
  156  * return the current number and list of required chunks caller must
  157  * guarantee ptr has space for up to 256 bytes
  158  */
  159 int
  160 sctp_serialize_auth_chunks(const sctp_auth_chklist_t *list, uint8_t *ptr)
  161 {
  162         int i, count = 0;
  163 
  164         if (list == NULL)
  165                 return (0);
  166 
  167         for (i = 0; i < 256; i++) {
  168                 if (list->chunks[i] != 0) {
  169                         *ptr++ = i;
  170                         count++;
  171                 }
  172         }
  173         return (count);
  174 }
  175 
  176 int
  177 sctp_pack_auth_chunks(const sctp_auth_chklist_t *list, uint8_t *ptr)
  178 {
  179         int i, size = 0;
  180 
  181         if (list == NULL)
  182                 return (0);
  183 
  184         if (list->num_chunks <= 32) {
  185                 /* just list them, one byte each */
  186                 for (i = 0; i < 256; i++) {
  187                         if (list->chunks[i] != 0) {
  188                                 *ptr++ = i;
  189                                 size++;
  190                         }
  191                 }
  192         } else {
  193                 int index, offset;
  194 
  195                 /* pack into a 32 byte bitfield */
  196                 for (i = 0; i < 256; i++) {
  197                         if (list->chunks[i] != 0) {
  198                                 index = i / 8;
  199                                 offset = i % 8;
  200                                 ptr[index] |= (1 << offset);
  201                         }
  202                 }
  203                 size = 32;
  204         }
  205         return (size);
  206 }
  207 
  208 int
  209 sctp_unpack_auth_chunks(const uint8_t *ptr, uint8_t num_chunks,
  210     sctp_auth_chklist_t *list)
  211 {
  212         int i;
  213         int size;
  214 
  215         if (list == NULL)
  216                 return (0);
  217 
  218         if (num_chunks <= 32) {
  219                 /* just pull them, one byte each */
  220                 for (i = 0; i < num_chunks; i++) {
  221                         (void)sctp_auth_add_chunk(*ptr++, list);
  222                 }
  223                 size = num_chunks;
  224         } else {
  225                 int index, offset;
  226 
  227                 /* unpack from a 32 byte bitfield */
  228                 for (index = 0; index < 32; index++) {
  229                         for (offset = 0; offset < 8; offset++) {
  230                                 if (ptr[index] & (1 << offset)) {
  231                                         (void)sctp_auth_add_chunk((index * 8) + offset, list);
  232                                 }
  233                         }
  234                 }
  235                 size = 32;
  236         }
  237         return (size);
  238 }
  239 
  240 
  241 /*
  242  * allocate structure space for a key of length keylen
  243  */
  244 sctp_key_t *
  245 sctp_alloc_key(uint32_t keylen)
  246 {
  247         sctp_key_t *new_key;
  248 
  249         SCTP_MALLOC(new_key, sctp_key_t *, sizeof(*new_key) + keylen,
  250             SCTP_M_AUTH_KY);
  251         if (new_key == NULL) {
  252                 /* out of memory */
  253                 return (NULL);
  254         }
  255         new_key->keylen = keylen;
  256         return (new_key);
  257 }
  258 
  259 void
  260 sctp_free_key(sctp_key_t *key)
  261 {
  262         if (key != NULL)
  263                 SCTP_FREE(key, SCTP_M_AUTH_KY);
  264 }
  265 
  266 void
  267 sctp_print_key(sctp_key_t *key, const char *str)
  268 {
  269         uint32_t i;
  270 
  271         if (key == NULL) {
  272                 SCTP_PRINTF("%s: [Null key]\n", str);
  273                 return;
  274         }
  275         SCTP_PRINTF("%s: len %u, ", str, key->keylen);
  276         if (key->keylen) {
  277                 for (i = 0; i < key->keylen; i++)
  278                         SCTP_PRINTF("%02x", key->key[i]);
  279                 SCTP_PRINTF("\n");
  280         } else {
  281                 SCTP_PRINTF("[Null key]\n");
  282         }
  283 }
  284 
  285 void
  286 sctp_show_key(sctp_key_t *key, const char *str)
  287 {
  288         uint32_t i;
  289 
  290         if (key == NULL) {
  291                 SCTP_PRINTF("%s: [Null key]\n", str);
  292                 return;
  293         }
  294         SCTP_PRINTF("%s: len %u, ", str, key->keylen);
  295         if (key->keylen) {
  296                 for (i = 0; i < key->keylen; i++)
  297                         SCTP_PRINTF("%02x", key->key[i]);
  298                 SCTP_PRINTF("\n");
  299         } else {
  300                 SCTP_PRINTF("[Null key]\n");
  301         }
  302 }
  303 
  304 static uint32_t
  305 sctp_get_keylen(sctp_key_t *key)
  306 {
  307         if (key != NULL)
  308                 return (key->keylen);
  309         else
  310                 return (0);
  311 }
  312 
  313 /*
  314  * generate a new random key of length 'keylen'
  315  */
  316 sctp_key_t *
  317 sctp_generate_random_key(uint32_t keylen)
  318 {
  319         sctp_key_t *new_key;
  320 
  321         new_key = sctp_alloc_key(keylen);
  322         if (new_key == NULL) {
  323                 /* out of memory */
  324                 return (NULL);
  325         }
  326         SCTP_READ_RANDOM(new_key->key, keylen);
  327         new_key->keylen = keylen;
  328         return (new_key);
  329 }
  330 
  331 sctp_key_t *
  332 sctp_set_key(uint8_t *key, uint32_t keylen)
  333 {
  334         sctp_key_t *new_key;
  335 
  336         new_key = sctp_alloc_key(keylen);
  337         if (new_key == NULL) {
  338                 /* out of memory */
  339                 return (NULL);
  340         }
  341         bcopy(key, new_key->key, keylen);
  342         return (new_key);
  343 }
  344 
  345 /*-
  346  * given two keys of variable size, compute which key is "larger/smaller"
  347  * returns:  1 if key1 > key2
  348  *          -1 if key1 < key2
  349  *           0 if key1 = key2
  350  */
  351 static int
  352 sctp_compare_key(sctp_key_t *key1, sctp_key_t *key2)
  353 {
  354         uint32_t maxlen;
  355         uint32_t i;
  356         uint32_t key1len, key2len;
  357         uint8_t *key_1, *key_2;
  358         uint8_t val1, val2;
  359 
  360         /* sanity/length check */
  361         key1len = sctp_get_keylen(key1);
  362         key2len = sctp_get_keylen(key2);
  363         if ((key1len == 0) && (key2len == 0))
  364                 return (0);
  365         else if (key1len == 0)
  366                 return (-1);
  367         else if (key2len == 0)
  368                 return (1);
  369 
  370         if (key1len < key2len) {
  371                 maxlen = key2len;
  372         } else {
  373                 maxlen = key1len;
  374         }
  375         key_1 = key1->key;
  376         key_2 = key2->key;
  377         /* check for numeric equality */
  378         for (i = 0; i < maxlen; i++) {
  379                 /* left-pad with zeros */
  380                 val1 = (i < (maxlen - key1len)) ? 0 : *(key_1++);
  381                 val2 = (i < (maxlen - key2len)) ? 0 : *(key_2++);
  382                 if (val1 > val2) {
  383                         return (1);
  384                 } else if (val1 < val2) {
  385                         return (-1);
  386                 }
  387         }
  388         /* keys are equal value, so check lengths */
  389         if (key1len == key2len)
  390                 return (0);
  391         else if (key1len < key2len)
  392                 return (-1);
  393         else
  394                 return (1);
  395 }
  396 
  397 /*
  398  * generate the concatenated keying material based on the two keys and the
  399  * shared key (if available). draft-ietf-tsvwg-auth specifies the specific
  400  * order for concatenation
  401  */
  402 sctp_key_t *
  403 sctp_compute_hashkey(sctp_key_t *key1, sctp_key_t *key2, sctp_key_t *shared)
  404 {
  405         uint32_t keylen;
  406         sctp_key_t *new_key;
  407         uint8_t *key_ptr;
  408 
  409         keylen = sctp_get_keylen(key1) + sctp_get_keylen(key2) +
  410             sctp_get_keylen(shared);
  411 
  412         if (keylen > 0) {
  413                 /* get space for the new key */
  414                 new_key = sctp_alloc_key(keylen);
  415                 if (new_key == NULL) {
  416                         /* out of memory */
  417                         return (NULL);
  418                 }
  419                 new_key->keylen = keylen;
  420                 key_ptr = new_key->key;
  421         } else {
  422                 /* all keys empty/null?! */
  423                 return (NULL);
  424         }
  425 
  426         /* concatenate the keys */
  427         if (sctp_compare_key(key1, key2) <= 0) {
  428                 /* key is shared + key1 + key2 */
  429                 if (sctp_get_keylen(shared)) {
  430                         bcopy(shared->key, key_ptr, shared->keylen);
  431                         key_ptr += shared->keylen;
  432                 }
  433                 if (sctp_get_keylen(key1)) {
  434                         bcopy(key1->key, key_ptr, key1->keylen);
  435                         key_ptr += key1->keylen;
  436                 }
  437                 if (sctp_get_keylen(key2)) {
  438                         bcopy(key2->key, key_ptr, key2->keylen);
  439                 }
  440         } else {
  441                 /* key is shared + key2 + key1 */
  442                 if (sctp_get_keylen(shared)) {
  443                         bcopy(shared->key, key_ptr, shared->keylen);
  444                         key_ptr += shared->keylen;
  445                 }
  446                 if (sctp_get_keylen(key2)) {
  447                         bcopy(key2->key, key_ptr, key2->keylen);
  448                         key_ptr += key2->keylen;
  449                 }
  450                 if (sctp_get_keylen(key1)) {
  451                         bcopy(key1->key, key_ptr, key1->keylen);
  452                 }
  453         }
  454         return (new_key);
  455 }
  456 
  457 
  458 sctp_sharedkey_t *
  459 sctp_alloc_sharedkey(void)
  460 {
  461         sctp_sharedkey_t *new_key;
  462 
  463         SCTP_MALLOC(new_key, sctp_sharedkey_t *, sizeof(*new_key),
  464             SCTP_M_AUTH_KY);
  465         if (new_key == NULL) {
  466                 /* out of memory */
  467                 return (NULL);
  468         }
  469         new_key->keyid = 0;
  470         new_key->key = NULL;
  471         new_key->refcount = 1;
  472         new_key->deactivated = 0;
  473         return (new_key);
  474 }
  475 
  476 void
  477 sctp_free_sharedkey(sctp_sharedkey_t *skey)
  478 {
  479         if (skey == NULL)
  480                 return;
  481 
  482         if (SCTP_DECREMENT_AND_CHECK_REFCOUNT(&skey->refcount)) {
  483                 if (skey->key != NULL)
  484                         sctp_free_key(skey->key);
  485                 SCTP_FREE(skey, SCTP_M_AUTH_KY);
  486         }
  487 }
  488 
  489 sctp_sharedkey_t *
  490 sctp_find_sharedkey(struct sctp_keyhead *shared_keys, uint16_t key_id)
  491 {
  492         sctp_sharedkey_t *skey;
  493 
  494         LIST_FOREACH(skey, shared_keys, next) {
  495                 if (skey->keyid == key_id)
  496                         return (skey);
  497         }
  498         return (NULL);
  499 }
  500 
  501 int
  502 sctp_insert_sharedkey(struct sctp_keyhead *shared_keys,
  503     sctp_sharedkey_t *new_skey)
  504 {
  505         sctp_sharedkey_t *skey;
  506 
  507         if ((shared_keys == NULL) || (new_skey == NULL))
  508                 return (EINVAL);
  509 
  510         /* insert into an empty list? */
  511         if (LIST_EMPTY(shared_keys)) {
  512                 LIST_INSERT_HEAD(shared_keys, new_skey, next);
  513                 return (0);
  514         }
  515         /* insert into the existing list, ordered by key id */
  516         LIST_FOREACH(skey, shared_keys, next) {
  517                 if (new_skey->keyid < skey->keyid) {
  518                         /* insert it before here */
  519                         LIST_INSERT_BEFORE(skey, new_skey, next);
  520                         return (0);
  521                 } else if (new_skey->keyid == skey->keyid) {
  522                         /* replace the existing key */
  523                         /* verify this key *can* be replaced */
  524                         if ((skey->deactivated) && (skey->refcount > 1)) {
  525                                 SCTPDBG(SCTP_DEBUG_AUTH1,
  526                                     "can't replace shared key id %u\n",
  527                                     new_skey->keyid);
  528                                 return (EBUSY);
  529                         }
  530                         SCTPDBG(SCTP_DEBUG_AUTH1,
  531                             "replacing shared key id %u\n",
  532                             new_skey->keyid);
  533                         LIST_INSERT_BEFORE(skey, new_skey, next);
  534                         LIST_REMOVE(skey, next);
  535                         sctp_free_sharedkey(skey);
  536                         return (0);
  537                 }
  538                 if (LIST_NEXT(skey, next) == NULL) {
  539                         /* belongs at the end of the list */
  540                         LIST_INSERT_AFTER(skey, new_skey, next);
  541                         return (0);
  542                 }
  543         }
  544         /* shouldn't reach here */
  545         return (EINVAL);
  546 }
  547 
  548 void
  549 sctp_auth_key_acquire(struct sctp_tcb *stcb, uint16_t key_id)
  550 {
  551         sctp_sharedkey_t *skey;
  552 
  553         /* find the shared key */
  554         skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, key_id);
  555 
  556         /* bump the ref count */
  557         if (skey) {
  558                 atomic_add_int(&skey->refcount, 1);
  559                 SCTPDBG(SCTP_DEBUG_AUTH2,
  560                     "%s: stcb %p key %u refcount acquire to %d\n",
  561                     __func__, (void *)stcb, key_id, skey->refcount);
  562         }
  563 }
  564 
  565 void
  566 sctp_auth_key_release(struct sctp_tcb *stcb, uint16_t key_id, int so_locked
  567 #if !defined(__APPLE__) && !defined(SCTP_SO_LOCK_TESTING)
  568     SCTP_UNUSED
  569 #endif
  570 )
  571 {
  572         sctp_sharedkey_t *skey;
  573 
  574         /* find the shared key */
  575         skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, key_id);
  576 
  577         /* decrement the ref count */
  578         if (skey) {
  579                 SCTPDBG(SCTP_DEBUG_AUTH2,
  580                     "%s: stcb %p key %u refcount release to %d\n",
  581                     __func__, (void *)stcb, key_id, skey->refcount);
  582 
  583                 /* see if a notification should be generated */
  584                 if ((skey->refcount <= 2) && (skey->deactivated)) {
  585                         /* notify ULP that key is no longer used */
  586                         sctp_ulp_notify(SCTP_NOTIFY_AUTH_FREE_KEY, stcb,
  587                             key_id, 0, so_locked);
  588                         SCTPDBG(SCTP_DEBUG_AUTH2,
  589                             "%s: stcb %p key %u no longer used, %d\n",
  590                             __func__, (void *)stcb, key_id, skey->refcount);
  591                 }
  592                 sctp_free_sharedkey(skey);
  593         }
  594 }
  595 
  596 static sctp_sharedkey_t *
  597 sctp_copy_sharedkey(const sctp_sharedkey_t *skey)
  598 {
  599         sctp_sharedkey_t *new_skey;
  600 
  601         if (skey == NULL)
  602                 return (NULL);
  603         new_skey = sctp_alloc_sharedkey();
  604         if (new_skey == NULL)
  605                 return (NULL);
  606         if (skey->key != NULL)
  607                 new_skey->key = sctp_set_key(skey->key->key, skey->key->keylen);
  608         else
  609                 new_skey->key = NULL;
  610         new_skey->keyid = skey->keyid;
  611         return (new_skey);
  612 }
  613 
  614 int
  615 sctp_copy_skeylist(const struct sctp_keyhead *src, struct sctp_keyhead *dest)
  616 {
  617         sctp_sharedkey_t *skey, *new_skey;
  618         int count = 0;
  619 
  620         if ((src == NULL) || (dest == NULL))
  621                 return (0);
  622         LIST_FOREACH(skey, src, next) {
  623                 new_skey = sctp_copy_sharedkey(skey);
  624                 if (new_skey != NULL) {
  625                         if (sctp_insert_sharedkey(dest, new_skey)) {
  626                                 sctp_free_sharedkey(new_skey);
  627                         } else {
  628                                 count++;
  629                         }
  630                 }
  631         }
  632         return (count);
  633 }
  634 
  635 
  636 sctp_hmaclist_t *
  637 sctp_alloc_hmaclist(uint16_t num_hmacs)
  638 {
  639         sctp_hmaclist_t *new_list;
  640         int alloc_size;
  641 
  642         alloc_size = sizeof(*new_list) + num_hmacs * sizeof(new_list->hmac[0]);
  643         SCTP_MALLOC(new_list, sctp_hmaclist_t *, alloc_size,
  644             SCTP_M_AUTH_HL);
  645         if (new_list == NULL) {
  646                 /* out of memory */
  647                 return (NULL);
  648         }
  649         new_list->max_algo = num_hmacs;
  650         new_list->num_algo = 0;
  651         return (new_list);
  652 }
  653 
  654 void
  655 sctp_free_hmaclist(sctp_hmaclist_t *list)
  656 {
  657         if (list != NULL) {
  658                 SCTP_FREE(list, SCTP_M_AUTH_HL);
  659                 list = NULL;
  660         }
  661 }
  662 
  663 int
  664 sctp_auth_add_hmacid(sctp_hmaclist_t *list, uint16_t hmac_id)
  665 {
  666         int i;
  667 
  668         if (list == NULL)
  669                 return (-1);
  670         if (list->num_algo == list->max_algo) {
  671                 SCTPDBG(SCTP_DEBUG_AUTH1,
  672                     "SCTP: HMAC id list full, ignoring add %u\n", hmac_id);
  673                 return (-1);
  674         }
  675         if ((hmac_id != SCTP_AUTH_HMAC_ID_SHA1) &&
  676             (hmac_id != SCTP_AUTH_HMAC_ID_SHA256)) {
  677                 return (-1);
  678         }
  679         /* Now is it already in the list */
  680         for (i = 0; i < list->num_algo; i++) {
  681                 if (list->hmac[i] == hmac_id) {
  682                         /* already in list */
  683                         return (-1);
  684                 }
  685         }
  686         SCTPDBG(SCTP_DEBUG_AUTH1, "SCTP: add HMAC id %u to list\n", hmac_id);
  687         list->hmac[list->num_algo++] = hmac_id;
  688         return (0);
  689 }
  690 
  691 sctp_hmaclist_t *
  692 sctp_copy_hmaclist(sctp_hmaclist_t *list)
  693 {
  694         sctp_hmaclist_t *new_list;
  695         int i;
  696 
  697         if (list == NULL)
  698                 return (NULL);
  699         /* get a new list */
  700         new_list = sctp_alloc_hmaclist(list->max_algo);
  701         if (new_list == NULL)
  702                 return (NULL);
  703         /* copy it */
  704         new_list->max_algo = list->max_algo;
  705         new_list->num_algo = list->num_algo;
  706         for (i = 0; i < list->num_algo; i++)
  707                 new_list->hmac[i] = list->hmac[i];
  708         return (new_list);
  709 }
  710 
  711 sctp_hmaclist_t *
  712 sctp_default_supported_hmaclist(void)
  713 {
  714         sctp_hmaclist_t *new_list;
  715 
  716         new_list = sctp_alloc_hmaclist(2);
  717         if (new_list == NULL)
  718                 return (NULL);
  719         /* We prefer SHA256, so list it first */
  720         (void)sctp_auth_add_hmacid(new_list, SCTP_AUTH_HMAC_ID_SHA256);
  721         (void)sctp_auth_add_hmacid(new_list, SCTP_AUTH_HMAC_ID_SHA1);
  722         return (new_list);
  723 }
  724 
  725 /*-
  726  * HMAC algos are listed in priority/preference order
  727  * find the best HMAC id to use for the peer based on local support
  728  */
  729 uint16_t
  730 sctp_negotiate_hmacid(sctp_hmaclist_t *peer, sctp_hmaclist_t *local)
  731 {
  732         int i, j;
  733 
  734         if ((local == NULL) || (peer == NULL))
  735                 return (SCTP_AUTH_HMAC_ID_RSVD);
  736 
  737         for (i = 0; i < peer->num_algo; i++) {
  738                 for (j = 0; j < local->num_algo; j++) {
  739                         if (peer->hmac[i] == local->hmac[j]) {
  740                                 /* found the "best" one */
  741                                 SCTPDBG(SCTP_DEBUG_AUTH1,
  742                                     "SCTP: negotiated peer HMAC id %u\n",
  743                                     peer->hmac[i]);
  744                                 return (peer->hmac[i]);
  745                         }
  746                 }
  747         }
  748         /* didn't find one! */
  749         return (SCTP_AUTH_HMAC_ID_RSVD);
  750 }
  751 
  752 /*-
  753  * serialize the HMAC algo list and return space used
  754  * caller must guarantee ptr has appropriate space
  755  */
  756 int
  757 sctp_serialize_hmaclist(sctp_hmaclist_t *list, uint8_t *ptr)
  758 {
  759         int i;
  760         uint16_t hmac_id;
  761 
  762         if (list == NULL)
  763                 return (0);
  764 
  765         for (i = 0; i < list->num_algo; i++) {
  766                 hmac_id = htons(list->hmac[i]);
  767                 bcopy(&hmac_id, ptr, sizeof(hmac_id));
  768                 ptr += sizeof(hmac_id);
  769         }
  770         return (list->num_algo * sizeof(hmac_id));
  771 }
  772 
  773 int
  774 sctp_verify_hmac_param(struct sctp_auth_hmac_algo *hmacs, uint32_t num_hmacs)
  775 {
  776         uint32_t i;
  777 
  778         for (i = 0; i < num_hmacs; i++) {
  779                 if (ntohs(hmacs->hmac_ids[i]) == SCTP_AUTH_HMAC_ID_SHA1) {
  780                         return (0);
  781                 }
  782         }
  783         return (-1);
  784 }
  785 
  786 sctp_authinfo_t *
  787 sctp_alloc_authinfo(void)
  788 {
  789         sctp_authinfo_t *new_authinfo;
  790 
  791         SCTP_MALLOC(new_authinfo, sctp_authinfo_t *, sizeof(*new_authinfo),
  792             SCTP_M_AUTH_IF);
  793 
  794         if (new_authinfo == NULL) {
  795                 /* out of memory */
  796                 return (NULL);
  797         }
  798         bzero(new_authinfo, sizeof(*new_authinfo));
  799         return (new_authinfo);
  800 }
  801 
  802 void
  803 sctp_free_authinfo(sctp_authinfo_t *authinfo)
  804 {
  805         if (authinfo == NULL)
  806                 return;
  807 
  808         if (authinfo->random != NULL)
  809                 sctp_free_key(authinfo->random);
  810         if (authinfo->peer_random != NULL)
  811                 sctp_free_key(authinfo->peer_random);
  812         if (authinfo->assoc_key != NULL)
  813                 sctp_free_key(authinfo->assoc_key);
  814         if (authinfo->recv_key != NULL)
  815                 sctp_free_key(authinfo->recv_key);
  816 
  817         /* We are NOT dynamically allocating authinfo's right now... */
  818         /* SCTP_FREE(authinfo, SCTP_M_AUTH_??); */
  819 }
  820 
  821 
  822 uint32_t
  823 sctp_get_auth_chunk_len(uint16_t hmac_algo)
  824 {
  825         int size;
  826 
  827         size = sizeof(struct sctp_auth_chunk) + sctp_get_hmac_digest_len(hmac_algo);
  828         return (SCTP_SIZE32(size));
  829 }
  830 
  831 uint32_t
  832 sctp_get_hmac_digest_len(uint16_t hmac_algo)
  833 {
  834         switch (hmac_algo) {
  835         case SCTP_AUTH_HMAC_ID_SHA1:
  836                 return (SCTP_AUTH_DIGEST_LEN_SHA1);
  837         case SCTP_AUTH_HMAC_ID_SHA256:
  838                 return (SCTP_AUTH_DIGEST_LEN_SHA256);
  839         default:
  840                 /* unknown HMAC algorithm: can't do anything */
  841                 return (0);
  842         }                       /* end switch */
  843 }
  844 
  845 static inline int
  846 sctp_get_hmac_block_len(uint16_t hmac_algo)
  847 {
  848         switch (hmac_algo) {
  849         case SCTP_AUTH_HMAC_ID_SHA1:
  850                 return (64);
  851         case SCTP_AUTH_HMAC_ID_SHA256:
  852                 return (64);
  853         case SCTP_AUTH_HMAC_ID_RSVD:
  854         default:
  855                 /* unknown HMAC algorithm: can't do anything */
  856                 return (0);
  857         }                       /* end switch */
  858 }
  859 
  860 static void
  861 sctp_hmac_init(uint16_t hmac_algo, sctp_hash_context_t *ctx)
  862 {
  863         switch (hmac_algo) {
  864         case SCTP_AUTH_HMAC_ID_SHA1:
  865                 SCTP_SHA1_INIT(&ctx->sha1);
  866                 break;
  867         case SCTP_AUTH_HMAC_ID_SHA256:
  868                 SCTP_SHA256_INIT(&ctx->sha256);
  869                 break;
  870         case SCTP_AUTH_HMAC_ID_RSVD:
  871         default:
  872                 /* unknown HMAC algorithm: can't do anything */
  873                 return;
  874         }                       /* end switch */
  875 }
  876 
  877 static void
  878 sctp_hmac_update(uint16_t hmac_algo, sctp_hash_context_t *ctx,
  879     uint8_t *text, uint32_t textlen)
  880 {
  881         switch (hmac_algo) {
  882         case SCTP_AUTH_HMAC_ID_SHA1:
  883                 SCTP_SHA1_UPDATE(&ctx->sha1, text, textlen);
  884                 break;
  885         case SCTP_AUTH_HMAC_ID_SHA256:
  886                 SCTP_SHA256_UPDATE(&ctx->sha256, text, textlen);
  887                 break;
  888         case SCTP_AUTH_HMAC_ID_RSVD:
  889         default:
  890                 /* unknown HMAC algorithm: can't do anything */
  891                 return;
  892         }                       /* end switch */
  893 }
  894 
  895 static void
  896 sctp_hmac_final(uint16_t hmac_algo, sctp_hash_context_t *ctx,
  897     uint8_t *digest)
  898 {
  899         switch (hmac_algo) {
  900         case SCTP_AUTH_HMAC_ID_SHA1:
  901                 SCTP_SHA1_FINAL(digest, &ctx->sha1);
  902                 break;
  903         case SCTP_AUTH_HMAC_ID_SHA256:
  904                 SCTP_SHA256_FINAL(digest, &ctx->sha256);
  905                 break;
  906         case SCTP_AUTH_HMAC_ID_RSVD:
  907         default:
  908                 /* unknown HMAC algorithm: can't do anything */
  909                 return;
  910         }                       /* end switch */
  911 }
  912 
  913 /*-
  914  * Keyed-Hashing for Message Authentication: FIPS 198 (RFC 2104)
  915  *
  916  * Compute the HMAC digest using the desired hash key, text, and HMAC
  917  * algorithm.  Resulting digest is placed in 'digest' and digest length
  918  * is returned, if the HMAC was performed.
  919  *
  920  * WARNING: it is up to the caller to supply sufficient space to hold the
  921  * resultant digest.
  922  */
  923 uint32_t
  924 sctp_hmac(uint16_t hmac_algo, uint8_t *key, uint32_t keylen,
  925     uint8_t *text, uint32_t textlen, uint8_t *digest)
  926 {
  927         uint32_t digestlen;
  928         uint32_t blocklen;
  929         sctp_hash_context_t ctx;
  930         uint8_t ipad[128], opad[128];   /* keyed hash inner/outer pads */
  931         uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
  932         uint32_t i;
  933 
  934         /* sanity check the material and length */
  935         if ((key == NULL) || (keylen == 0) || (text == NULL) ||
  936             (textlen == 0) || (digest == NULL)) {
  937                 /* can't do HMAC with empty key or text or digest store */
  938                 return (0);
  939         }
  940         /* validate the hmac algo and get the digest length */
  941         digestlen = sctp_get_hmac_digest_len(hmac_algo);
  942         if (digestlen == 0)
  943                 return (0);
  944 
  945         /* hash the key if it is longer than the hash block size */
  946         blocklen = sctp_get_hmac_block_len(hmac_algo);
  947         if (keylen > blocklen) {
  948                 sctp_hmac_init(hmac_algo, &ctx);
  949                 sctp_hmac_update(hmac_algo, &ctx, key, keylen);
  950                 sctp_hmac_final(hmac_algo, &ctx, temp);
  951                 /* set the hashed key as the key */
  952                 keylen = digestlen;
  953                 key = temp;
  954         }
  955         /* initialize the inner/outer pads with the key and "append" zeroes */
  956         bzero(ipad, blocklen);
  957         bzero(opad, blocklen);
  958         bcopy(key, ipad, keylen);
  959         bcopy(key, opad, keylen);
  960 
  961         /* XOR the key with ipad and opad values */
  962         for (i = 0; i < blocklen; i++) {
  963                 ipad[i] ^= 0x36;
  964                 opad[i] ^= 0x5c;
  965         }
  966 
  967         /* perform inner hash */
  968         sctp_hmac_init(hmac_algo, &ctx);
  969         sctp_hmac_update(hmac_algo, &ctx, ipad, blocklen);
  970         sctp_hmac_update(hmac_algo, &ctx, text, textlen);
  971         sctp_hmac_final(hmac_algo, &ctx, temp);
  972 
  973         /* perform outer hash */
  974         sctp_hmac_init(hmac_algo, &ctx);
  975         sctp_hmac_update(hmac_algo, &ctx, opad, blocklen);
  976         sctp_hmac_update(hmac_algo, &ctx, temp, digestlen);
  977         sctp_hmac_final(hmac_algo, &ctx, digest);
  978 
  979         return (digestlen);
  980 }
  981 
  982 /* mbuf version */
  983 uint32_t
  984 sctp_hmac_m(uint16_t hmac_algo, uint8_t *key, uint32_t keylen,
  985     struct mbuf *m, uint32_t m_offset, uint8_t *digest, uint32_t trailer)
  986 {
  987         uint32_t digestlen;
  988         uint32_t blocklen;
  989         sctp_hash_context_t ctx;
  990         uint8_t ipad[128], opad[128];   /* keyed hash inner/outer pads */
  991         uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
  992         uint32_t i;
  993         struct mbuf *m_tmp;
  994 
  995         /* sanity check the material and length */
  996         if ((key == NULL) || (keylen == 0) || (m == NULL) || (digest == NULL)) {
  997                 /* can't do HMAC with empty key or text or digest store */
  998                 return (0);
  999         }
 1000         /* validate the hmac algo and get the digest length */
 1001         digestlen = sctp_get_hmac_digest_len(hmac_algo);
 1002         if (digestlen == 0)
 1003                 return (0);
 1004 
 1005         /* hash the key if it is longer than the hash block size */
 1006         blocklen = sctp_get_hmac_block_len(hmac_algo);
 1007         if (keylen > blocklen) {
 1008                 sctp_hmac_init(hmac_algo, &ctx);
 1009                 sctp_hmac_update(hmac_algo, &ctx, key, keylen);
 1010                 sctp_hmac_final(hmac_algo, &ctx, temp);
 1011                 /* set the hashed key as the key */
 1012                 keylen = digestlen;
 1013                 key = temp;
 1014         }
 1015         /* initialize the inner/outer pads with the key and "append" zeroes */
 1016         bzero(ipad, blocklen);
 1017         bzero(opad, blocklen);
 1018         bcopy(key, ipad, keylen);
 1019         bcopy(key, opad, keylen);
 1020 
 1021         /* XOR the key with ipad and opad values */
 1022         for (i = 0; i < blocklen; i++) {
 1023                 ipad[i] ^= 0x36;
 1024                 opad[i] ^= 0x5c;
 1025         }
 1026 
 1027         /* perform inner hash */
 1028         sctp_hmac_init(hmac_algo, &ctx);
 1029         sctp_hmac_update(hmac_algo, &ctx, ipad, blocklen);
 1030         /* find the correct starting mbuf and offset (get start of text) */
 1031         m_tmp = m;
 1032         while ((m_tmp != NULL) && (m_offset >= (uint32_t)SCTP_BUF_LEN(m_tmp))) {
 1033                 m_offset -= SCTP_BUF_LEN(m_tmp);
 1034                 m_tmp = SCTP_BUF_NEXT(m_tmp);
 1035         }
 1036         /* now use the rest of the mbuf chain for the text */
 1037         while (m_tmp != NULL) {
 1038                 if ((SCTP_BUF_NEXT(m_tmp) == NULL) && trailer) {
 1039                         sctp_hmac_update(hmac_algo, &ctx, mtod(m_tmp, uint8_t *)+m_offset,
 1040                             SCTP_BUF_LEN(m_tmp) - (trailer + m_offset));
 1041                 } else {
 1042                         sctp_hmac_update(hmac_algo, &ctx, mtod(m_tmp, uint8_t *)+m_offset,
 1043                             SCTP_BUF_LEN(m_tmp) - m_offset);
 1044                 }
 1045 
 1046                 /* clear the offset since it's only for the first mbuf */
 1047                 m_offset = 0;
 1048                 m_tmp = SCTP_BUF_NEXT(m_tmp);
 1049         }
 1050         sctp_hmac_final(hmac_algo, &ctx, temp);
 1051 
 1052         /* perform outer hash */
 1053         sctp_hmac_init(hmac_algo, &ctx);
 1054         sctp_hmac_update(hmac_algo, &ctx, opad, blocklen);
 1055         sctp_hmac_update(hmac_algo, &ctx, temp, digestlen);
 1056         sctp_hmac_final(hmac_algo, &ctx, digest);
 1057 
 1058         return (digestlen);
 1059 }
 1060 
 1061 /*-
 1062  * verify the HMAC digest using the desired hash key, text, and HMAC
 1063  * algorithm.
 1064  * Returns -1 on error, 0 on success.
 1065  */
 1066 int
 1067 sctp_verify_hmac(uint16_t hmac_algo, uint8_t *key, uint32_t keylen,
 1068     uint8_t *text, uint32_t textlen,
 1069     uint8_t *digest, uint32_t digestlen)
 1070 {
 1071         uint32_t len;
 1072         uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
 1073 
 1074         /* sanity check the material and length */
 1075         if ((key == NULL) || (keylen == 0) ||
 1076             (text == NULL) || (textlen == 0) || (digest == NULL)) {
 1077                 /* can't do HMAC with empty key or text or digest */
 1078                 return (-1);
 1079         }
 1080         len = sctp_get_hmac_digest_len(hmac_algo);
 1081         if ((len == 0) || (digestlen != len))
 1082                 return (-1);
 1083 
 1084         /* compute the expected hash */
 1085         if (sctp_hmac(hmac_algo, key, keylen, text, textlen, temp) != len)
 1086                 return (-1);
 1087 
 1088         if (memcmp(digest, temp, digestlen) != 0)
 1089                 return (-1);
 1090         else
 1091                 return (0);
 1092 }
 1093 
 1094 
 1095 /*
 1096  * computes the requested HMAC using a key struct (which may be modified if
 1097  * the keylen exceeds the HMAC block len).
 1098  */
 1099 uint32_t
 1100 sctp_compute_hmac(uint16_t hmac_algo, sctp_key_t *key, uint8_t *text,
 1101     uint32_t textlen, uint8_t *digest)
 1102 {
 1103         uint32_t digestlen;
 1104         uint32_t blocklen;
 1105         sctp_hash_context_t ctx;
 1106         uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
 1107 
 1108         /* sanity check */
 1109         if ((key == NULL) || (text == NULL) || (textlen == 0) ||
 1110             (digest == NULL)) {
 1111                 /* can't do HMAC with empty key or text or digest store */
 1112                 return (0);
 1113         }
 1114         /* validate the hmac algo and get the digest length */
 1115         digestlen = sctp_get_hmac_digest_len(hmac_algo);
 1116         if (digestlen == 0)
 1117                 return (0);
 1118 
 1119         /* hash the key if it is longer than the hash block size */
 1120         blocklen = sctp_get_hmac_block_len(hmac_algo);
 1121         if (key->keylen > blocklen) {
 1122                 sctp_hmac_init(hmac_algo, &ctx);
 1123                 sctp_hmac_update(hmac_algo, &ctx, key->key, key->keylen);
 1124                 sctp_hmac_final(hmac_algo, &ctx, temp);
 1125                 /* save the hashed key as the new key */
 1126                 key->keylen = digestlen;
 1127                 bcopy(temp, key->key, key->keylen);
 1128         }
 1129         return (sctp_hmac(hmac_algo, key->key, key->keylen, text, textlen,
 1130             digest));
 1131 }
 1132 
 1133 /* mbuf version */
 1134 uint32_t
 1135 sctp_compute_hmac_m(uint16_t hmac_algo, sctp_key_t *key, struct mbuf *m,
 1136     uint32_t m_offset, uint8_t *digest)
 1137 {
 1138         uint32_t digestlen;
 1139         uint32_t blocklen;
 1140         sctp_hash_context_t ctx;
 1141         uint8_t temp[SCTP_AUTH_DIGEST_LEN_MAX];
 1142 
 1143         /* sanity check */
 1144         if ((key == NULL) || (m == NULL) || (digest == NULL)) {
 1145                 /* can't do HMAC with empty key or text or digest store */
 1146                 return (0);
 1147         }
 1148         /* validate the hmac algo and get the digest length */
 1149         digestlen = sctp_get_hmac_digest_len(hmac_algo);
 1150         if (digestlen == 0)
 1151                 return (0);
 1152 
 1153         /* hash the key if it is longer than the hash block size */
 1154         blocklen = sctp_get_hmac_block_len(hmac_algo);
 1155         if (key->keylen > blocklen) {
 1156                 sctp_hmac_init(hmac_algo, &ctx);
 1157                 sctp_hmac_update(hmac_algo, &ctx, key->key, key->keylen);
 1158                 sctp_hmac_final(hmac_algo, &ctx, temp);
 1159                 /* save the hashed key as the new key */
 1160                 key->keylen = digestlen;
 1161                 bcopy(temp, key->key, key->keylen);
 1162         }
 1163         return (sctp_hmac_m(hmac_algo, key->key, key->keylen, m, m_offset, digest, 0));
 1164 }
 1165 
 1166 int
 1167 sctp_auth_is_supported_hmac(sctp_hmaclist_t *list, uint16_t id)
 1168 {
 1169         int i;
 1170 
 1171         if ((list == NULL) || (id == SCTP_AUTH_HMAC_ID_RSVD))
 1172                 return (0);
 1173 
 1174         for (i = 0; i < list->num_algo; i++)
 1175                 if (list->hmac[i] == id)
 1176                         return (1);
 1177 
 1178         /* not in the list */
 1179         return (0);
 1180 }
 1181 
 1182 
 1183 /*-
 1184  * clear any cached key(s) if they match the given key id on an association.
 1185  * the cached key(s) will be recomputed and re-cached at next use.
 1186  * ASSUMES TCB_LOCK is already held
 1187  */
 1188 void
 1189 sctp_clear_cachedkeys(struct sctp_tcb *stcb, uint16_t keyid)
 1190 {
 1191         if (stcb == NULL)
 1192                 return;
 1193 
 1194         if (keyid == stcb->asoc.authinfo.assoc_keyid) {
 1195                 sctp_free_key(stcb->asoc.authinfo.assoc_key);
 1196                 stcb->asoc.authinfo.assoc_key = NULL;
 1197         }
 1198         if (keyid == stcb->asoc.authinfo.recv_keyid) {
 1199                 sctp_free_key(stcb->asoc.authinfo.recv_key);
 1200                 stcb->asoc.authinfo.recv_key = NULL;
 1201         }
 1202 }
 1203 
 1204 /*-
 1205  * clear any cached key(s) if they match the given key id for all assocs on
 1206  * an endpoint.
 1207  * ASSUMES INP_WLOCK is already held
 1208  */
 1209 void
 1210 sctp_clear_cachedkeys_ep(struct sctp_inpcb *inp, uint16_t keyid)
 1211 {
 1212         struct sctp_tcb *stcb;
 1213 
 1214         if (inp == NULL)
 1215                 return;
 1216 
 1217         /* clear the cached keys on all assocs on this instance */
 1218         LIST_FOREACH(stcb, &inp->sctp_asoc_list, sctp_tcblist) {
 1219                 SCTP_TCB_LOCK(stcb);
 1220                 sctp_clear_cachedkeys(stcb, keyid);
 1221                 SCTP_TCB_UNLOCK(stcb);
 1222         }
 1223 }
 1224 
 1225 /*-
 1226  * delete a shared key from an association
 1227  * ASSUMES TCB_LOCK is already held
 1228  */
 1229 int
 1230 sctp_delete_sharedkey(struct sctp_tcb *stcb, uint16_t keyid)
 1231 {
 1232         sctp_sharedkey_t *skey;
 1233 
 1234         if (stcb == NULL)
 1235                 return (-1);
 1236 
 1237         /* is the keyid the assoc active sending key */
 1238         if (keyid == stcb->asoc.authinfo.active_keyid)
 1239                 return (-1);
 1240 
 1241         /* does the key exist? */
 1242         skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
 1243         if (skey == NULL)
 1244                 return (-1);
 1245 
 1246         /* are there other refcount holders on the key? */
 1247         if (skey->refcount > 1)
 1248                 return (-1);
 1249 
 1250         /* remove it */
 1251         LIST_REMOVE(skey, next);
 1252         sctp_free_sharedkey(skey);      /* frees skey->key as well */
 1253 
 1254         /* clear any cached keys */
 1255         sctp_clear_cachedkeys(stcb, keyid);
 1256         return (0);
 1257 }
 1258 
 1259 /*-
 1260  * deletes a shared key from the endpoint
 1261  * ASSUMES INP_WLOCK is already held
 1262  */
 1263 int
 1264 sctp_delete_sharedkey_ep(struct sctp_inpcb *inp, uint16_t keyid)
 1265 {
 1266         sctp_sharedkey_t *skey;
 1267 
 1268         if (inp == NULL)
 1269                 return (-1);
 1270 
 1271         /* is the keyid the active sending key on the endpoint */
 1272         if (keyid == inp->sctp_ep.default_keyid)
 1273                 return (-1);
 1274 
 1275         /* does the key exist? */
 1276         skey = sctp_find_sharedkey(&inp->sctp_ep.shared_keys, keyid);
 1277         if (skey == NULL)
 1278                 return (-1);
 1279 
 1280         /* endpoint keys are not refcounted */
 1281 
 1282         /* remove it */
 1283         LIST_REMOVE(skey, next);
 1284         sctp_free_sharedkey(skey);      /* frees skey->key as well */
 1285 
 1286         /* clear any cached keys */
 1287         sctp_clear_cachedkeys_ep(inp, keyid);
 1288         return (0);
 1289 }
 1290 
 1291 /*-
 1292  * set the active key on an association
 1293  * ASSUMES TCB_LOCK is already held
 1294  */
 1295 int
 1296 sctp_auth_setactivekey(struct sctp_tcb *stcb, uint16_t keyid)
 1297 {
 1298         sctp_sharedkey_t *skey = NULL;
 1299 
 1300         /* find the key on the assoc */
 1301         skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
 1302         if (skey == NULL) {
 1303                 /* that key doesn't exist */
 1304                 return (-1);
 1305         }
 1306         if ((skey->deactivated) && (skey->refcount > 1)) {
 1307                 /* can't reactivate a deactivated key with other refcounts */
 1308                 return (-1);
 1309         }
 1310         /* set the (new) active key */
 1311         stcb->asoc.authinfo.active_keyid = keyid;
 1312         /* reset the deactivated flag */
 1313         skey->deactivated = 0;
 1314 
 1315         return (0);
 1316 }
 1317 
 1318 /*-
 1319  * set the active key on an endpoint
 1320  * ASSUMES INP_WLOCK is already held
 1321  */
 1322 int
 1323 sctp_auth_setactivekey_ep(struct sctp_inpcb *inp, uint16_t keyid)
 1324 {
 1325         sctp_sharedkey_t *skey;
 1326 
 1327         /* find the key */
 1328         skey = sctp_find_sharedkey(&inp->sctp_ep.shared_keys, keyid);
 1329         if (skey == NULL) {
 1330                 /* that key doesn't exist */
 1331                 return (-1);
 1332         }
 1333         inp->sctp_ep.default_keyid = keyid;
 1334         return (0);
 1335 }
 1336 
 1337 /*-
 1338  * deactivates a shared key from the association
 1339  * ASSUMES INP_WLOCK is already held
 1340  */
 1341 int
 1342 sctp_deact_sharedkey(struct sctp_tcb *stcb, uint16_t keyid)
 1343 {
 1344         sctp_sharedkey_t *skey;
 1345 
 1346         if (stcb == NULL)
 1347                 return (-1);
 1348 
 1349         /* is the keyid the assoc active sending key */
 1350         if (keyid == stcb->asoc.authinfo.active_keyid)
 1351                 return (-1);
 1352 
 1353         /* does the key exist? */
 1354         skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
 1355         if (skey == NULL)
 1356                 return (-1);
 1357 
 1358         /* are there other refcount holders on the key? */
 1359         if (skey->refcount == 1) {
 1360                 /* no other users, send a notification for this key */
 1361                 sctp_ulp_notify(SCTP_NOTIFY_AUTH_FREE_KEY, stcb, keyid, 0,
 1362                     SCTP_SO_LOCKED);
 1363         }
 1364         /* mark the key as deactivated */
 1365         skey->deactivated = 1;
 1366 
 1367         return (0);
 1368 }
 1369 
 1370 /*-
 1371  * deactivates a shared key from the endpoint
 1372  * ASSUMES INP_WLOCK is already held
 1373  */
 1374 int
 1375 sctp_deact_sharedkey_ep(struct sctp_inpcb *inp, uint16_t keyid)
 1376 {
 1377         sctp_sharedkey_t *skey;
 1378 
 1379         if (inp == NULL)
 1380                 return (-1);
 1381 
 1382         /* is the keyid the active sending key on the endpoint */
 1383         if (keyid == inp->sctp_ep.default_keyid)
 1384                 return (-1);
 1385 
 1386         /* does the key exist? */
 1387         skey = sctp_find_sharedkey(&inp->sctp_ep.shared_keys, keyid);
 1388         if (skey == NULL)
 1389                 return (-1);
 1390 
 1391         /* endpoint keys are not refcounted */
 1392 
 1393         /* remove it */
 1394         LIST_REMOVE(skey, next);
 1395         sctp_free_sharedkey(skey);      /* frees skey->key as well */
 1396 
 1397         return (0);
 1398 }
 1399 
 1400 /*
 1401  * get local authentication parameters from cookie (from INIT-ACK)
 1402  */
 1403 void
 1404 sctp_auth_get_cookie_params(struct sctp_tcb *stcb, struct mbuf *m,
 1405     uint32_t offset, uint32_t length)
 1406 {
 1407         struct sctp_paramhdr *phdr, tmp_param;
 1408         uint16_t plen, ptype;
 1409         uint8_t random_store[SCTP_PARAM_BUFFER_SIZE];
 1410         struct sctp_auth_random *p_random = NULL;
 1411         uint16_t random_len = 0;
 1412         uint8_t hmacs_store[SCTP_PARAM_BUFFER_SIZE];
 1413         struct sctp_auth_hmac_algo *hmacs = NULL;
 1414         uint16_t hmacs_len = 0;
 1415         uint8_t chunks_store[SCTP_PARAM_BUFFER_SIZE];
 1416         struct sctp_auth_chunk_list *chunks = NULL;
 1417         uint16_t num_chunks = 0;
 1418         sctp_key_t *new_key;
 1419         uint32_t keylen;
 1420 
 1421         /* convert to upper bound */
 1422         length += offset;
 1423 
 1424         phdr = (struct sctp_paramhdr *)sctp_m_getptr(m, offset,
 1425             sizeof(struct sctp_paramhdr), (uint8_t *)&tmp_param);
 1426         while (phdr != NULL) {
 1427                 ptype = ntohs(phdr->param_type);
 1428                 plen = ntohs(phdr->param_length);
 1429 
 1430                 if ((plen == 0) || (offset + plen > length))
 1431                         break;
 1432 
 1433                 if (ptype == SCTP_RANDOM) {
 1434                         if (plen > sizeof(random_store))
 1435                                 break;
 1436                         phdr = sctp_get_next_param(m, offset,
 1437                             (struct sctp_paramhdr *)random_store, plen);
 1438                         if (phdr == NULL)
 1439                                 return;
 1440                         /* save the random and length for the key */
 1441                         p_random = (struct sctp_auth_random *)phdr;
 1442                         random_len = plen - sizeof(*p_random);
 1443                 } else if (ptype == SCTP_HMAC_LIST) {
 1444                         uint16_t num_hmacs;
 1445                         uint16_t i;
 1446 
 1447                         if (plen > sizeof(hmacs_store))
 1448                                 break;
 1449                         phdr = sctp_get_next_param(m, offset,
 1450                             (struct sctp_paramhdr *)hmacs_store, plen);
 1451                         if (phdr == NULL)
 1452                                 return;
 1453                         /* save the hmacs list and num for the key */
 1454                         hmacs = (struct sctp_auth_hmac_algo *)phdr;
 1455                         hmacs_len = plen - sizeof(*hmacs);
 1456                         num_hmacs = hmacs_len / sizeof(hmacs->hmac_ids[0]);
 1457                         if (stcb->asoc.local_hmacs != NULL)
 1458                                 sctp_free_hmaclist(stcb->asoc.local_hmacs);
 1459                         stcb->asoc.local_hmacs = sctp_alloc_hmaclist(num_hmacs);
 1460                         if (stcb->asoc.local_hmacs != NULL) {
 1461                                 for (i = 0; i < num_hmacs; i++) {
 1462                                         (void)sctp_auth_add_hmacid(stcb->asoc.local_hmacs,
 1463                                             ntohs(hmacs->hmac_ids[i]));
 1464                                 }
 1465                         }
 1466                 } else if (ptype == SCTP_CHUNK_LIST) {
 1467                         int i;
 1468 
 1469                         if (plen > sizeof(chunks_store))
 1470                                 break;
 1471                         phdr = sctp_get_next_param(m, offset,
 1472                             (struct sctp_paramhdr *)chunks_store, plen);
 1473                         if (phdr == NULL)
 1474                                 return;
 1475                         chunks = (struct sctp_auth_chunk_list *)phdr;
 1476                         num_chunks = plen - sizeof(*chunks);
 1477                         /* save chunks list and num for the key */
 1478                         if (stcb->asoc.local_auth_chunks != NULL)
 1479                                 sctp_clear_chunklist(stcb->asoc.local_auth_chunks);
 1480                         else
 1481                                 stcb->asoc.local_auth_chunks = sctp_alloc_chunklist();
 1482                         for (i = 0; i < num_chunks; i++) {
 1483                                 (void)sctp_auth_add_chunk(chunks->chunk_types[i],
 1484                                     stcb->asoc.local_auth_chunks);
 1485                         }
 1486                 }
 1487                 /* get next parameter */
 1488                 offset += SCTP_SIZE32(plen);
 1489                 if (offset + sizeof(struct sctp_paramhdr) > length)
 1490                         break;
 1491                 phdr = (struct sctp_paramhdr *)sctp_m_getptr(m, offset, sizeof(struct sctp_paramhdr),
 1492                     (uint8_t *)&tmp_param);
 1493         }
 1494         /* concatenate the full random key */
 1495         keylen = sizeof(*p_random) + random_len + sizeof(*hmacs) + hmacs_len;
 1496         if (chunks != NULL) {
 1497                 keylen += sizeof(*chunks) + num_chunks;
 1498         }
 1499         new_key = sctp_alloc_key(keylen);
 1500         if (new_key != NULL) {
 1501                 /* copy in the RANDOM */
 1502                 if (p_random != NULL) {
 1503                         keylen = sizeof(*p_random) + random_len;
 1504                         bcopy(p_random, new_key->key, keylen);
 1505                 }
 1506                 /* append in the AUTH chunks */
 1507                 if (chunks != NULL) {
 1508                         bcopy(chunks, new_key->key + keylen,
 1509                             sizeof(*chunks) + num_chunks);
 1510                         keylen += sizeof(*chunks) + num_chunks;
 1511                 }
 1512                 /* append in the HMACs */
 1513                 if (hmacs != NULL) {
 1514                         bcopy(hmacs, new_key->key + keylen,
 1515                             sizeof(*hmacs) + hmacs_len);
 1516                 }
 1517         }
 1518         if (stcb->asoc.authinfo.random != NULL)
 1519                 sctp_free_key(stcb->asoc.authinfo.random);
 1520         stcb->asoc.authinfo.random = new_key;
 1521         stcb->asoc.authinfo.random_len = random_len;
 1522         sctp_clear_cachedkeys(stcb, stcb->asoc.authinfo.assoc_keyid);
 1523         sctp_clear_cachedkeys(stcb, stcb->asoc.authinfo.recv_keyid);
 1524 
 1525         /* negotiate what HMAC to use for the peer */
 1526         stcb->asoc.peer_hmac_id = sctp_negotiate_hmacid(stcb->asoc.peer_hmacs,
 1527             stcb->asoc.local_hmacs);
 1528 
 1529         /* copy defaults from the endpoint */
 1530         /* FIX ME: put in cookie? */
 1531         stcb->asoc.authinfo.active_keyid = stcb->sctp_ep->sctp_ep.default_keyid;
 1532         /* copy out the shared key list (by reference) from the endpoint */
 1533         (void)sctp_copy_skeylist(&stcb->sctp_ep->sctp_ep.shared_keys,
 1534             &stcb->asoc.shared_keys);
 1535 }
 1536 
 1537 /*
 1538  * compute and fill in the HMAC digest for a packet
 1539  */
 1540 void
 1541 sctp_fill_hmac_digest_m(struct mbuf *m, uint32_t auth_offset,
 1542     struct sctp_auth_chunk *auth, struct sctp_tcb *stcb, uint16_t keyid)
 1543 {
 1544         uint32_t digestlen;
 1545         sctp_sharedkey_t *skey;
 1546         sctp_key_t *key;
 1547 
 1548         if ((stcb == NULL) || (auth == NULL))
 1549                 return;
 1550 
 1551         /* zero the digest + chunk padding */
 1552         digestlen = sctp_get_hmac_digest_len(stcb->asoc.peer_hmac_id);
 1553         bzero(auth->hmac, SCTP_SIZE32(digestlen));
 1554 
 1555         /* is the desired key cached? */
 1556         if ((keyid != stcb->asoc.authinfo.assoc_keyid) ||
 1557             (stcb->asoc.authinfo.assoc_key == NULL)) {
 1558                 if (stcb->asoc.authinfo.assoc_key != NULL) {
 1559                         /* free the old cached key */
 1560                         sctp_free_key(stcb->asoc.authinfo.assoc_key);
 1561                 }
 1562                 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys, keyid);
 1563                 /* the only way skey is NULL is if null key id 0 is used */
 1564                 if (skey != NULL)
 1565                         key = skey->key;
 1566                 else
 1567                         key = NULL;
 1568                 /* compute a new assoc key and cache it */
 1569                 stcb->asoc.authinfo.assoc_key =
 1570                     sctp_compute_hashkey(stcb->asoc.authinfo.random,
 1571                     stcb->asoc.authinfo.peer_random, key);
 1572                 stcb->asoc.authinfo.assoc_keyid = keyid;
 1573                 SCTPDBG(SCTP_DEBUG_AUTH1, "caching key id %u\n",
 1574                     stcb->asoc.authinfo.assoc_keyid);
 1575 #ifdef SCTP_DEBUG
 1576                 if (SCTP_AUTH_DEBUG)
 1577                         sctp_print_key(stcb->asoc.authinfo.assoc_key,
 1578                             "Assoc Key");
 1579 #endif
 1580         }
 1581         /* set in the active key id */
 1582         auth->shared_key_id = htons(keyid);
 1583 
 1584         /* compute and fill in the digest */
 1585         (void)sctp_compute_hmac_m(stcb->asoc.peer_hmac_id, stcb->asoc.authinfo.assoc_key,
 1586             m, auth_offset, auth->hmac);
 1587 }
 1588 
 1589 
 1590 static void
 1591 sctp_bzero_m(struct mbuf *m, uint32_t m_offset, uint32_t size)
 1592 {
 1593         struct mbuf *m_tmp;
 1594         uint8_t *data;
 1595 
 1596         /* sanity check */
 1597         if (m == NULL)
 1598                 return;
 1599 
 1600         /* find the correct starting mbuf and offset (get start position) */
 1601         m_tmp = m;
 1602         while ((m_tmp != NULL) && (m_offset >= (uint32_t)SCTP_BUF_LEN(m_tmp))) {
 1603                 m_offset -= SCTP_BUF_LEN(m_tmp);
 1604                 m_tmp = SCTP_BUF_NEXT(m_tmp);
 1605         }
 1606         /* now use the rest of the mbuf chain */
 1607         while ((m_tmp != NULL) && (size > 0)) {
 1608                 data = mtod(m_tmp, uint8_t *)+m_offset;
 1609                 if (size > (uint32_t)SCTP_BUF_LEN(m_tmp)) {
 1610                         bzero(data, SCTP_BUF_LEN(m_tmp));
 1611                         size -= SCTP_BUF_LEN(m_tmp);
 1612                 } else {
 1613                         bzero(data, size);
 1614                         size = 0;
 1615                 }
 1616                 /* clear the offset since it's only for the first mbuf */
 1617                 m_offset = 0;
 1618                 m_tmp = SCTP_BUF_NEXT(m_tmp);
 1619         }
 1620 }
 1621 
 1622 /*-
 1623  * process the incoming Authentication chunk
 1624  * return codes:
 1625  *   -1 on any authentication error
 1626  *    0 on authentication verification
 1627  */
 1628 int
 1629 sctp_handle_auth(struct sctp_tcb *stcb, struct sctp_auth_chunk *auth,
 1630     struct mbuf *m, uint32_t offset)
 1631 {
 1632         uint16_t chunklen;
 1633         uint16_t shared_key_id;
 1634         uint16_t hmac_id;
 1635         sctp_sharedkey_t *skey;
 1636         uint32_t digestlen;
 1637         uint8_t digest[SCTP_AUTH_DIGEST_LEN_MAX];
 1638         uint8_t computed_digest[SCTP_AUTH_DIGEST_LEN_MAX];
 1639 
 1640         /* auth is checked for NULL by caller */
 1641         chunklen = ntohs(auth->ch.chunk_length);
 1642         if (chunklen < sizeof(*auth)) {
 1643                 SCTP_STAT_INCR(sctps_recvauthfailed);
 1644                 return (-1);
 1645         }
 1646         SCTP_STAT_INCR(sctps_recvauth);
 1647 
 1648         /* get the auth params */
 1649         shared_key_id = ntohs(auth->shared_key_id);
 1650         hmac_id = ntohs(auth->hmac_id);
 1651         SCTPDBG(SCTP_DEBUG_AUTH1,
 1652             "SCTP AUTH Chunk: shared key %u, HMAC id %u\n",
 1653             shared_key_id, hmac_id);
 1654 
 1655         /* is the indicated HMAC supported? */
 1656         if (!sctp_auth_is_supported_hmac(stcb->asoc.local_hmacs, hmac_id)) {
 1657                 struct mbuf *op_err;
 1658                 struct sctp_error_auth_invalid_hmac *cause;
 1659 
 1660                 SCTP_STAT_INCR(sctps_recvivalhmacid);
 1661                 SCTPDBG(SCTP_DEBUG_AUTH1,
 1662                     "SCTP Auth: unsupported HMAC id %u\n",
 1663                     hmac_id);
 1664                 /*
 1665                  * report this in an Error Chunk: Unsupported HMAC
 1666                  * Identifier
 1667                  */
 1668                 op_err = sctp_get_mbuf_for_msg(sizeof(struct sctp_error_auth_invalid_hmac),
 1669                     0, M_NOWAIT, 1, MT_HEADER);
 1670                 if (op_err != NULL) {
 1671                         /* pre-reserve some space */
 1672                         SCTP_BUF_RESV_UF(op_err, sizeof(struct sctp_chunkhdr));
 1673                         /* fill in the error */
 1674                         cause = mtod(op_err, struct sctp_error_auth_invalid_hmac *);
 1675                         cause->cause.code = htons(SCTP_CAUSE_UNSUPPORTED_HMACID);
 1676                         cause->cause.length = htons(sizeof(struct sctp_error_auth_invalid_hmac));
 1677                         cause->hmac_id = ntohs(hmac_id);
 1678                         SCTP_BUF_LEN(op_err) = sizeof(struct sctp_error_auth_invalid_hmac);
 1679                         /* queue it */
 1680                         sctp_queue_op_err(stcb, op_err);
 1681                 }
 1682                 return (-1);
 1683         }
 1684         /* get the indicated shared key, if available */
 1685         if ((stcb->asoc.authinfo.recv_key == NULL) ||
 1686             (stcb->asoc.authinfo.recv_keyid != shared_key_id)) {
 1687                 /* find the shared key on the assoc first */
 1688                 skey = sctp_find_sharedkey(&stcb->asoc.shared_keys,
 1689                     shared_key_id);
 1690                 /* if the shared key isn't found, discard the chunk */
 1691                 if (skey == NULL) {
 1692                         SCTP_STAT_INCR(sctps_recvivalkeyid);
 1693                         SCTPDBG(SCTP_DEBUG_AUTH1,
 1694                             "SCTP Auth: unknown key id %u\n",
 1695                             shared_key_id);
 1696                         return (-1);
 1697                 }
 1698                 /* generate a notification if this is a new key id */
 1699                 if (stcb->asoc.authinfo.recv_keyid != shared_key_id)
 1700                         /*
 1701                          * sctp_ulp_notify(SCTP_NOTIFY_AUTH_NEW_KEY, stcb,
 1702                          * shared_key_id, (void
 1703                          * *)stcb->asoc.authinfo.recv_keyid);
 1704                          */
 1705                         sctp_notify_authentication(stcb, SCTP_AUTH_NEW_KEY,
 1706                             shared_key_id, stcb->asoc.authinfo.recv_keyid,
 1707                             SCTP_SO_NOT_LOCKED);
 1708                 /* compute a new recv assoc key and cache it */
 1709                 if (stcb->asoc.authinfo.recv_key != NULL)
 1710                         sctp_free_key(stcb->asoc.authinfo.recv_key);
 1711                 stcb->asoc.authinfo.recv_key =
 1712                     sctp_compute_hashkey(stcb->asoc.authinfo.random,
 1713                     stcb->asoc.authinfo.peer_random, skey->key);
 1714                 stcb->asoc.authinfo.recv_keyid = shared_key_id;
 1715 #ifdef SCTP_DEBUG
 1716                 if (SCTP_AUTH_DEBUG)
 1717                         sctp_print_key(stcb->asoc.authinfo.recv_key, "Recv Key");
 1718 #endif
 1719         }
 1720         /* validate the digest length */
 1721         digestlen = sctp_get_hmac_digest_len(hmac_id);
 1722         if (chunklen < (sizeof(*auth) + digestlen)) {
 1723                 /* invalid digest length */
 1724                 SCTP_STAT_INCR(sctps_recvauthfailed);
 1725                 SCTPDBG(SCTP_DEBUG_AUTH1,
 1726                     "SCTP Auth: chunk too short for HMAC\n");
 1727                 return (-1);
 1728         }
 1729         /* save a copy of the digest, zero the pseudo header, and validate */
 1730         bcopy(auth->hmac, digest, digestlen);
 1731         sctp_bzero_m(m, offset + sizeof(*auth), SCTP_SIZE32(digestlen));
 1732         (void)sctp_compute_hmac_m(hmac_id, stcb->asoc.authinfo.recv_key,
 1733             m, offset, computed_digest);
 1734 
 1735         /* compare the computed digest with the one in the AUTH chunk */
 1736         if (memcmp(digest, computed_digest, digestlen) != 0) {
 1737                 SCTP_STAT_INCR(sctps_recvauthfailed);
 1738                 SCTPDBG(SCTP_DEBUG_AUTH1,
 1739                     "SCTP Auth: HMAC digest check failed\n");
 1740                 return (-1);
 1741         }
 1742         return (0);
 1743 }
 1744 
 1745 /*
 1746  * Generate NOTIFICATION
 1747  */
 1748 void
 1749 sctp_notify_authentication(struct sctp_tcb *stcb, uint32_t indication,
 1750     uint16_t keyid, uint16_t alt_keyid, int so_locked
 1751 #if !defined(__APPLE__) && !defined(SCTP_SO_LOCK_TESTING)
 1752     SCTP_UNUSED
 1753 #endif
 1754 )
 1755 {
 1756         struct mbuf *m_notify;
 1757         struct sctp_authkey_event *auth;
 1758         struct sctp_queued_to_read *control;
 1759 
 1760         if ((stcb == NULL) ||
 1761             (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) ||
 1762             (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_ALLGONE) ||
 1763             (stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET)
 1764             ) {
 1765                 /* If the socket is gone we are out of here */
 1766                 return;
 1767         }
 1768         if (sctp_stcb_is_feature_off(stcb->sctp_ep, stcb, SCTP_PCB_FLAGS_AUTHEVNT))
 1769                 /* event not enabled */
 1770                 return;
 1771 
 1772         m_notify = sctp_get_mbuf_for_msg(sizeof(struct sctp_authkey_event),
 1773             0, M_NOWAIT, 1, MT_HEADER);
 1774         if (m_notify == NULL)
 1775                 /* no space left */
 1776                 return;
 1777 
 1778         SCTP_BUF_LEN(m_notify) = 0;
 1779         auth = mtod(m_notify, struct sctp_authkey_event *);
 1780         memset(auth, 0, sizeof(struct sctp_authkey_event));
 1781         auth->auth_type = SCTP_AUTHENTICATION_EVENT;
 1782         auth->auth_flags = 0;
 1783         auth->auth_length = sizeof(*auth);
 1784         auth->auth_keynumber = keyid;
 1785         auth->auth_altkeynumber = alt_keyid;
 1786         auth->auth_indication = indication;
 1787         auth->auth_assoc_id = sctp_get_associd(stcb);
 1788 
 1789         SCTP_BUF_LEN(m_notify) = sizeof(*auth);
 1790         SCTP_BUF_NEXT(m_notify) = NULL;
 1791 
 1792         /* append to socket */
 1793         control = sctp_build_readq_entry(stcb, stcb->asoc.primary_destination,
 1794             0, 0, stcb->asoc.context, 0, 0, 0, m_notify);
 1795         if (control == NULL) {
 1796                 /* no memory */
 1797                 sctp_m_freem(m_notify);
 1798                 return;
 1799         }
 1800         control->spec_flags = M_NOTIFICATION;
 1801         control->length = SCTP_BUF_LEN(m_notify);
 1802         /* not that we need this */
 1803         control->tail_mbuf = m_notify;
 1804         sctp_add_to_readq(stcb->sctp_ep, stcb, control,
 1805             &stcb->sctp_socket->so_rcv, 1, SCTP_READ_LOCK_NOT_HELD, so_locked);
 1806 }
 1807 
 1808 
 1809 /*-
 1810  * validates the AUTHentication related parameters in an INIT/INIT-ACK
 1811  * Note: currently only used for INIT as INIT-ACK is handled inline
 1812  * with sctp_load_addresses_from_init()
 1813  */
 1814 int
 1815 sctp_validate_init_auth_params(struct mbuf *m, int offset, int limit)
 1816 {
 1817         struct sctp_paramhdr *phdr, param_buf;
 1818         uint16_t ptype, plen;
 1819         int peer_supports_asconf = 0;
 1820         int peer_supports_auth = 0;
 1821         int got_random = 0, got_hmacs = 0, got_chklist = 0;
 1822         uint8_t saw_asconf = 0;
 1823         uint8_t saw_asconf_ack = 0;
 1824 
 1825         /* go through each of the params. */
 1826         phdr = sctp_get_next_param(m, offset, &param_buf, sizeof(param_buf));
 1827         while (phdr) {
 1828                 ptype = ntohs(phdr->param_type);
 1829                 plen = ntohs(phdr->param_length);
 1830 
 1831                 if (offset + plen > limit) {
 1832                         break;
 1833                 }
 1834                 if (plen < sizeof(struct sctp_paramhdr)) {
 1835                         break;
 1836                 }
 1837                 if (ptype == SCTP_SUPPORTED_CHUNK_EXT) {
 1838                         /* A supported extension chunk */
 1839                         struct sctp_supported_chunk_types_param *pr_supported;
 1840                         uint8_t local_store[SCTP_SMALL_CHUNK_STORE];
 1841                         int num_ent, i;
 1842 
 1843                         if (plen > sizeof(local_store)) {
 1844                                 break;
 1845                         }
 1846                         phdr = sctp_get_next_param(m, offset,
 1847                             (struct sctp_paramhdr *)&local_store,
 1848                             plen);
 1849                         if (phdr == NULL) {
 1850                                 return (-1);
 1851                         }
 1852                         pr_supported = (struct sctp_supported_chunk_types_param *)phdr;
 1853                         num_ent = plen - sizeof(struct sctp_paramhdr);
 1854                         for (i = 0; i < num_ent; i++) {
 1855                                 switch (pr_supported->chunk_types[i]) {
 1856                                 case SCTP_ASCONF:
 1857                                 case SCTP_ASCONF_ACK:
 1858                                         peer_supports_asconf = 1;
 1859                                         break;
 1860                                 default:
 1861                                         /* one we don't care about */
 1862                                         break;
 1863                                 }
 1864                         }
 1865                 } else if (ptype == SCTP_RANDOM) {
 1866                         /* enforce the random length */
 1867                         if (plen != (sizeof(struct sctp_auth_random) +
 1868                             SCTP_AUTH_RANDOM_SIZE_REQUIRED)) {
 1869                                 SCTPDBG(SCTP_DEBUG_AUTH1,
 1870                                     "SCTP: invalid RANDOM len\n");
 1871                                 return (-1);
 1872                         }
 1873                         got_random = 1;
 1874                 } else if (ptype == SCTP_HMAC_LIST) {
 1875                         struct sctp_auth_hmac_algo *hmacs;
 1876                         uint8_t store[SCTP_PARAM_BUFFER_SIZE];
 1877                         int num_hmacs;
 1878 
 1879                         if (plen > sizeof(store)) {
 1880                                 break;
 1881                         }
 1882                         phdr = sctp_get_next_param(m, offset,
 1883                             (struct sctp_paramhdr *)store,
 1884                             plen);
 1885                         if (phdr == NULL) {
 1886                                 return (-1);
 1887                         }
 1888                         hmacs = (struct sctp_auth_hmac_algo *)phdr;
 1889                         num_hmacs = (plen - sizeof(*hmacs)) / sizeof(hmacs->hmac_ids[0]);
 1890                         /* validate the hmac list */
 1891                         if (sctp_verify_hmac_param(hmacs, num_hmacs)) {
 1892                                 SCTPDBG(SCTP_DEBUG_AUTH1,
 1893                                     "SCTP: invalid HMAC param\n");
 1894                                 return (-1);
 1895                         }
 1896                         got_hmacs = 1;
 1897                 } else if (ptype == SCTP_CHUNK_LIST) {
 1898                         struct sctp_auth_chunk_list *chunks;
 1899                         uint8_t chunks_store[SCTP_SMALL_CHUNK_STORE];
 1900                         int i, num_chunks;
 1901 
 1902                         if (plen > sizeof(chunks_store)) {
 1903                                 break;
 1904                         }
 1905                         phdr = sctp_get_next_param(m, offset,
 1906                             (struct sctp_paramhdr *)chunks_store,
 1907                             plen);
 1908                         if (phdr == NULL) {
 1909                                 return (-1);
 1910                         }
 1911                         /*-
 1912                          * Flip through the list and mark that the
 1913                          * peer supports asconf/asconf_ack.
 1914                          */
 1915                         chunks = (struct sctp_auth_chunk_list *)phdr;
 1916                         num_chunks = plen - sizeof(*chunks);
 1917                         for (i = 0; i < num_chunks; i++) {
 1918                                 /* record asconf/asconf-ack if listed */
 1919                                 if (chunks->chunk_types[i] == SCTP_ASCONF)
 1920                                         saw_asconf = 1;
 1921                                 if (chunks->chunk_types[i] == SCTP_ASCONF_ACK)
 1922                                         saw_asconf_ack = 1;
 1923 
 1924                         }
 1925                         if (num_chunks)
 1926                                 got_chklist = 1;
 1927                 }
 1928                 offset += SCTP_SIZE32(plen);
 1929                 if (offset >= limit) {
 1930                         break;
 1931                 }
 1932                 phdr = sctp_get_next_param(m, offset, &param_buf,
 1933                     sizeof(param_buf));
 1934         }
 1935         /* validate authentication required parameters */
 1936         if (got_random && got_hmacs) {
 1937                 peer_supports_auth = 1;
 1938         } else {
 1939                 peer_supports_auth = 0;
 1940         }
 1941         if (!peer_supports_auth && got_chklist) {
 1942                 SCTPDBG(SCTP_DEBUG_AUTH1,
 1943                     "SCTP: peer sent chunk list w/o AUTH\n");
 1944                 return (-1);
 1945         }
 1946         if (peer_supports_asconf && !peer_supports_auth) {
 1947                 SCTPDBG(SCTP_DEBUG_AUTH1,
 1948                     "SCTP: peer supports ASCONF but not AUTH\n");
 1949                 return (-1);
 1950         } else if ((peer_supports_asconf) && (peer_supports_auth) &&
 1951             ((saw_asconf == 0) || (saw_asconf_ack == 0))) {
 1952                 return (-2);
 1953         }
 1954         return (0);
 1955 }
 1956 
 1957 void
 1958 sctp_initialize_auth_params(struct sctp_inpcb *inp, struct sctp_tcb *stcb)
 1959 {
 1960         uint16_t chunks_len = 0;
 1961         uint16_t hmacs_len = 0;
 1962         uint16_t random_len = SCTP_AUTH_RANDOM_SIZE_DEFAULT;
 1963         sctp_key_t *new_key;
 1964         uint16_t keylen;
 1965 
 1966         /* initialize hmac list from endpoint */
 1967         stcb->asoc.local_hmacs = sctp_copy_hmaclist(inp->sctp_ep.local_hmacs);
 1968         if (stcb->asoc.local_hmacs != NULL) {
 1969                 hmacs_len = stcb->asoc.local_hmacs->num_algo *
 1970                     sizeof(stcb->asoc.local_hmacs->hmac[0]);
 1971         }
 1972         /* initialize auth chunks list from endpoint */
 1973         stcb->asoc.local_auth_chunks =
 1974             sctp_copy_chunklist(inp->sctp_ep.local_auth_chunks);
 1975         if (stcb->asoc.local_auth_chunks != NULL) {
 1976                 int i;
 1977 
 1978                 for (i = 0; i < 256; i++) {
 1979                         if (stcb->asoc.local_auth_chunks->chunks[i])
 1980                                 chunks_len++;
 1981                 }
 1982         }
 1983         /* copy defaults from the endpoint */
 1984         stcb->asoc.authinfo.active_keyid = inp->sctp_ep.default_keyid;
 1985 
 1986         /* copy out the shared key list (by reference) from the endpoint */
 1987         (void)sctp_copy_skeylist(&inp->sctp_ep.shared_keys,
 1988             &stcb->asoc.shared_keys);
 1989 
 1990         /* now set the concatenated key (random + chunks + hmacs) */
 1991         /* key includes parameter headers */
 1992         keylen = (3 * sizeof(struct sctp_paramhdr)) + random_len + chunks_len +
 1993             hmacs_len;
 1994         new_key = sctp_alloc_key(keylen);
 1995         if (new_key != NULL) {
 1996                 struct sctp_paramhdr *ph;
 1997                 int plen;
 1998 
 1999                 /* generate and copy in the RANDOM */
 2000                 ph = (struct sctp_paramhdr *)new_key->key;
 2001                 ph->param_type = htons(SCTP_RANDOM);
 2002                 plen = sizeof(*ph) + random_len;
 2003                 ph->param_length = htons(plen);
 2004                 SCTP_READ_RANDOM(new_key->key + sizeof(*ph), random_len);
 2005                 keylen = plen;
 2006 
 2007                 /* append in the AUTH chunks */
 2008                 /* NOTE: currently we always have chunks to list */
 2009                 ph = (struct sctp_paramhdr *)(new_key->key + keylen);
 2010                 ph->param_type = htons(SCTP_CHUNK_LIST);
 2011                 plen = sizeof(*ph) + chunks_len;
 2012                 ph->param_length = htons(plen);
 2013                 keylen += sizeof(*ph);
 2014                 if (stcb->asoc.local_auth_chunks) {
 2015                         int i;
 2016 
 2017                         for (i = 0; i < 256; i++) {
 2018                                 if (stcb->asoc.local_auth_chunks->chunks[i])
 2019                                         new_key->key[keylen++] = i;
 2020                         }
 2021                 }
 2022                 /* append in the HMACs */
 2023                 ph = (struct sctp_paramhdr *)(new_key->key + keylen);
 2024                 ph->param_type = htons(SCTP_HMAC_LIST);
 2025                 plen = sizeof(*ph) + hmacs_len;
 2026                 ph->param_length = htons(plen);
 2027                 keylen += sizeof(*ph);
 2028                 (void)sctp_serialize_hmaclist(stcb->asoc.local_hmacs,
 2029                     new_key->key + keylen);
 2030         }
 2031         if (stcb->asoc.authinfo.random != NULL)
 2032                 sctp_free_key(stcb->asoc.authinfo.random);
 2033         stcb->asoc.authinfo.random = new_key;
 2034         stcb->asoc.authinfo.random_len = random_len;
 2035 }
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FreeBSD/Linux Kernel Cross Reference sys/netinet/sctp_auth.c

FreeBSD/Linux Kernel Cross Reference
sys/netinet/sctp_auth.c
