1/*-
2 * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. The name of the author may not be used to endorse or promote products
14 * derived from this software without specific prior written permission.
15 *
16 * Alternatively, this software may be distributed under the terms of the
17 * GNU General Public License ("GPL") version 2 as published by the Free
18 * Software Foundation.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
21 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
24 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#include <sys/cdefs.h>
33#ifdef __FreeBSD__
34__FBSDID("$FreeBSD: src/sys/net80211/ieee80211_crypto_ccmp.c,v 1.7 2005/07/11 03:06:23 sam Exp $");
35#endif
36#ifdef __NetBSD__
37__KERNEL_RCSID(0, "$NetBSD: ieee80211_crypto_ccmp.c,v 1.11 2014/10/18 08:33:29 snj Exp $");
38#endif
39
40/*
41 * IEEE 802.11i AES-CCMP crypto support.
42 *
43 * Part of this module is derived from similar code in the Host
44 * AP driver. The code is used with the consent of the author and
45 * its license is included below.
46 */
47#include <sys/param.h>
48#include <sys/systm.h>
49#include <sys/mbuf.h>
50#include <sys/malloc.h>
51#include <sys/kernel.h>
52
53#include <sys/socket.h>
54
55#include <net/if.h>
56#include <net/if_ether.h>
57#include <net/if_media.h>
58
59#include <net80211/ieee80211_var.h>
60
61#include <crypto/rijndael/rijndael.h>
62
63#define AES_BLOCK_LEN 16
64
65struct ccmp_ctx {
66 struct ieee80211com *cc_ic; /* for diagnostics */
67 rijndael_ctx cc_aes;
68};
69
70static void *ccmp_attach(struct ieee80211com *, struct ieee80211_key *);
71static void ccmp_detach(struct ieee80211_key *);
72static int ccmp_setkey(struct ieee80211_key *);
73static int ccmp_encap(struct ieee80211_key *k, struct mbuf *, u_int8_t keyid);
74static int ccmp_decap(struct ieee80211_key *, struct mbuf *, int);
75static int ccmp_enmic(struct ieee80211_key *, struct mbuf *, int);
76static int ccmp_demic(struct ieee80211_key *, struct mbuf *, int);
77
78const struct ieee80211_cipher ieee80211_cipher_ccmp = {
79 .ic_name = "AES-CCM",
80 .ic_cipher = IEEE80211_CIPHER_AES_CCM,
81 .ic_header = IEEE80211_WEP_IVLEN + IEEE80211_WEP_KIDLEN +
82 IEEE80211_WEP_EXTIVLEN,
83 .ic_trailer = IEEE80211_WEP_MICLEN,
84 .ic_miclen = 0,
85 .ic_attach = ccmp_attach,
86 .ic_detach = ccmp_detach,
87 .ic_setkey = ccmp_setkey,
88 .ic_encap = ccmp_encap,
89 .ic_decap = ccmp_decap,
90 .ic_enmic = ccmp_enmic,
91 .ic_demic = ccmp_demic,
92};
93
94#define ccmp ieee80211_cipher_ccmp
95
96static int ccmp_encrypt(struct ieee80211_key *, struct mbuf *, int hdrlen);
97static int ccmp_decrypt(struct ieee80211_key *, u_int64_t pn,
98 struct mbuf *, int hdrlen);
99
100static void *
101ccmp_attach(struct ieee80211com *ic, struct ieee80211_key *k)
102{
103 struct ccmp_ctx *ctx;
104
105 ctx = malloc(sizeof(struct ccmp_ctx),
106 M_DEVBUF, M_NOWAIT | M_ZERO);
107 if (ctx == NULL) {
108 ic->ic_stats.is_crypto_nomem++;
109 return NULL;
110 }
111 ctx->cc_ic = ic;
112 return ctx;
113}
114
115static void
116ccmp_detach(struct ieee80211_key *k)
117{
118 struct ccmp_ctx *ctx = k->wk_private;
119
120 free(ctx, M_DEVBUF);
121}
122
123static int
124ccmp_setkey(struct ieee80211_key *k)
125{
126 struct ccmp_ctx *ctx = k->wk_private;
127
128 if (k->wk_keylen != (128/NBBY)) {
129 IEEE80211_DPRINTF(ctx->cc_ic, IEEE80211_MSG_CRYPTO,
130 "%s: Invalid key length %u, expecting %u\n",
131 __func__, k->wk_keylen, 128/NBBY);
132 return 0;
133 }
134 if (k->wk_flags & IEEE80211_KEY_SWCRYPT)
135 rijndael_set_key(&ctx->cc_aes, k->wk_key, k->wk_keylen*NBBY);
136 return 1;
137}
138
139/*
140 * Add privacy headers appropriate for the specified key.
141 */
142static int
143ccmp_encap(struct ieee80211_key *k, struct mbuf *m, u_int8_t keyid)
144{
145 struct ccmp_ctx *ctx = k->wk_private;
146 struct ieee80211com *ic = ctx->cc_ic;
147 u_int8_t *ivp;
148 int hdrlen;
149
150 hdrlen = ieee80211_hdrspace(ic, mtod(m, void *));
151
152 /*
153 * Copy down 802.11 header and add the IV, KeyID, and ExtIV.
154 */
155 M_PREPEND(m, ccmp.ic_header, M_NOWAIT);
156 if (m == NULL)
157 return 0;
158 ivp = mtod(m, u_int8_t *);
159 ovbcopy(ivp + ccmp.ic_header, ivp, hdrlen);
160 ivp += hdrlen;
161
162 k->wk_keytsc++; /* XXX wrap at 48 bits */
163 ivp[0] = k->wk_keytsc >> 0; /* PN0 */
164 ivp[1] = k->wk_keytsc >> 8; /* PN1 */
165 ivp[2] = 0; /* Reserved */
166 ivp[3] = keyid | IEEE80211_WEP_EXTIV; /* KeyID | ExtID */
167 ivp[4] = k->wk_keytsc >> 16; /* PN2 */
168 ivp[5] = k->wk_keytsc >> 24; /* PN3 */
169 ivp[6] = k->wk_keytsc >> 32; /* PN4 */
170 ivp[7] = k->wk_keytsc >> 40; /* PN5 */
171
172 /*
173 * Finally, do software encrypt if neeed.
174 */
175 if ((k->wk_flags & IEEE80211_KEY_SWCRYPT) &&
176 !ccmp_encrypt(k, m, hdrlen))
177 return 0;
178
179 return 1;
180}
181
182/*
183 * Add MIC to the frame as needed.
184 */
185static int
186ccmp_enmic(struct ieee80211_key *k, struct mbuf *m,
187 int force)
188{
189
190 return 1;
191}
192
193static __inline uint64_t
194READ_6(uint8_t b0, uint8_t b1, uint8_t b2, uint8_t b3, uint8_t b4, uint8_t b5)
195{
196 uint32_t iv32 = (b0 << 0) | (b1 << 8) | (b2 << 16) | (b3 << 24);
197 uint16_t iv16 = (b4 << 0) | (b5 << 8);
198 return (((uint64_t)iv16) << 32) | iv32;
199}
200
201/*
202 * Validate and strip privacy headers (and trailer) for a
203 * received frame. The specified key should be correct but
204 * is also verified.
205 */
206static int
207ccmp_decap(struct ieee80211_key *k, struct mbuf *m, int hdrlen)
208{
209 struct ccmp_ctx *ctx = k->wk_private;
210 struct ieee80211_frame *wh;
211 uint8_t *ivp;
212 uint64_t pn;
213
214 /*
215 * Header should have extended IV and sequence number;
216 * verify the former and validate the latter.
217 */
218 wh = mtod(m, struct ieee80211_frame *);
219 ivp = mtod(m, uint8_t *) + hdrlen;
220 if ((ivp[IEEE80211_WEP_IVLEN] & IEEE80211_WEP_EXTIV) == 0) {
221 /*
222 * No extended IV; discard frame.
223 */
224 IEEE80211_DPRINTF(ctx->cc_ic, IEEE80211_MSG_CRYPTO,
225 "[%s] Missing ExtIV for AES-CCM cipher\n",
226 ether_sprintf(wh->i_addr2));
227 ctx->cc_ic->ic_stats.is_rx_ccmpformat++;
228 return 0;
229 }
230 pn = READ_6(ivp[0], ivp[1], ivp[4], ivp[5], ivp[6], ivp[7]);
231 if (pn <= k->wk_keyrsc) {
232 /*
233 * Replay violation.
234 */
235 ieee80211_notify_replay_failure(ctx->cc_ic, wh, k, pn);
236 ctx->cc_ic->ic_stats.is_rx_ccmpreplay++;
237 return 0;
238 }
239
240 /*
241 * Check if the device handled the decrypt in hardware.
242 * If so we just strip the header; otherwise we need to
243 * handle the decrypt in software. Note that for the
244 * latter we leave the header in place for use in the
245 * decryption work.
246 */
247 if ((k->wk_flags & IEEE80211_KEY_SWCRYPT) &&
248 !ccmp_decrypt(k, pn, m, hdrlen))
249 return 0;
250
251 /*
252 * Copy up 802.11 header and strip crypto bits.
253 */
254 ovbcopy(mtod(m, void *), mtod(m, u_int8_t *) + ccmp.ic_header, hdrlen);
255 m_adj(m, ccmp.ic_header);
256 m_adj(m, -ccmp.ic_trailer);
257
258 /*
259 * Ok to update rsc now.
260 */
261 k->wk_keyrsc = pn;
262
263 return 1;
264}
265
266/*
267 * Verify and strip MIC from the frame.
268 */
269static int
270ccmp_demic(struct ieee80211_key *k, struct mbuf *m,
271 int force)
272{
273 return 1;
274}
275
276static __inline void
277xor_block(uint8_t *b, const uint8_t *a, size_t len)
278{
279 int i;
280 for (i = 0; i < len; i++)
281 b[i] ^= a[i];
282}
283
284/*
285 * Host AP crypt: host-based CCMP encryption implementation for Host AP driver
286 *
287 * Copyright (c) 2003-2004, Jouni Malinen <jkmaline@cc.hut.fi>
288 *
289 * This program is free software; you can redistribute it and/or modify
290 * it under the terms of the GNU General Public License version 2 as
291 * published by the Free Software Foundation. See README and COPYING for
292 * more details.
293 *
294 * Alternatively, this software may be distributed under the terms of BSD
295 * license.
296 */
297
298static void
299ccmp_init_blocks(rijndael_ctx *ctx, struct ieee80211_frame *wh,
300 u_int64_t pn, size_t dlen,
301 uint8_t b0[AES_BLOCK_LEN], uint8_t aad[2 * AES_BLOCK_LEN],
302 uint8_t auth[AES_BLOCK_LEN], uint8_t s0[AES_BLOCK_LEN])
303{
304#define IS_4ADDRESS(wh) \
305 ((wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) == IEEE80211_FC1_DIR_DSTODS)
306#define IS_QOS_DATA(wh) ieee80211_has_qos(wh)
307
308 /* CCM Initial Block:
309 * Flag (Include authentication header, M=3 (8-octet MIC),
310 * L=1 (2-octet Dlen))
311 * Nonce: 0x00 | A2 | PN
312 * Dlen */
313 b0[0] = 0x59;
314 /* NB: b0[1] set below */
315 IEEE80211_ADDR_COPY(b0 + 2, wh->i_addr2);
316 b0[8] = pn >> 40;
317 b0[9] = pn >> 32;
318 b0[10] = pn >> 24;
319 b0[11] = pn >> 16;
320 b0[12] = pn >> 8;
321 b0[13] = pn >> 0;
322 b0[14] = (dlen >> 8) & 0xff;
323 b0[15] = dlen & 0xff;
324
325 /* AAD:
326 * FC with bits 4..6 and 11..13 masked to zero; 14 is always one
327 * A1 | A2 | A3
328 * SC with bits 4..15 (seq#) masked to zero
329 * A4 (if present)
330 * QC (if present)
331 */
332 aad[0] = 0; /* AAD length >> 8 */
333 /* NB: aad[1] set below */
334 aad[2] = wh->i_fc[0] & 0x8f; /* XXX magic #s */
335 aad[3] = wh->i_fc[1] & 0xc7; /* XXX magic #s */
336 /* NB: we know 3 addresses are contiguous */
337 memcpy(aad + 4, wh->i_addr1, 3 * IEEE80211_ADDR_LEN);
338 aad[22] = wh->i_seq[0] & IEEE80211_SEQ_FRAG_MASK;
339 aad[23] = 0; /* all bits masked */
340 /*
341 * Construct variable-length portion of AAD based
342 * on whether this is a 4-address frame/QOS frame.
343 * We always zero-pad to 32 bytes before running it
344 * through the cipher.
345 *
346 * We also fill in the priority bits of the CCM
347 * initial block as we know whether or not we have
348 * a QOS frame.
349 */
350 if (IS_4ADDRESS(wh)) {
351 IEEE80211_ADDR_COPY(aad + 24,
352 ((struct ieee80211_frame_addr4 *)wh)->i_addr4);
353 if (IS_QOS_DATA(wh)) {
354 struct ieee80211_qosframe_addr4 *qwh4 =
355 (struct ieee80211_qosframe_addr4 *) wh;
356 aad[30] = qwh4->i_qos[0] & 0x0f;/* just priority bits */
357 aad[31] = 0;
358 b0[1] = aad[30];
359 aad[1] = 22 + IEEE80211_ADDR_LEN + 2;
360 } else {
361 *(u_int16_t *)&aad[30] = 0;
362 b0[1] = 0;
363 aad[1] = 22 + IEEE80211_ADDR_LEN;
364 }
365 } else {
366 if (IS_QOS_DATA(wh)) {
367 struct ieee80211_qosframe *qwh =
368 (struct ieee80211_qosframe*) wh;
369 aad[24] = qwh->i_qos[0] & 0x0f; /* just priority bits */
370 aad[25] = 0;
371 b0[1] = aad[24];
372 aad[1] = 22 + 2;
373 } else {
374 *(u_int16_t *)&aad[24] = 0;
375 b0[1] = 0;
376 aad[1] = 22;
377 }
378 *(u_int16_t *)&aad[26] = 0;
379 *(u_int32_t *)&aad[28] = 0;
380 }
381
382 /* Start with the first block and AAD */
383 rijndael_encrypt(ctx, b0, auth);
384 xor_block(auth, aad, AES_BLOCK_LEN);
385 rijndael_encrypt(ctx, auth, auth);
386 xor_block(auth, &aad[AES_BLOCK_LEN], AES_BLOCK_LEN);
387 rijndael_encrypt(ctx, auth, auth);
388 b0[0] &= 0x07;
389 b0[14] = b0[15] = 0;
390 rijndael_encrypt(ctx, b0, s0);
391#undef IS_QOS_DATA
392#undef IS_4ADDRESS
393}
394
395#define CCMP_ENCRYPT(_i, _b, _b0, _pos, _e, _len) do { \
396 /* Authentication */ \
397 xor_block(_b, _pos, _len); \
398 rijndael_encrypt(&ctx->cc_aes, _b, _b); \
399 /* Encryption, with counter */ \
400 _b0[14] = (_i >> 8) & 0xff; \
401 _b0[15] = _i & 0xff; \
402 rijndael_encrypt(&ctx->cc_aes, _b0, _e); \
403 xor_block(_pos, _e, _len); \
404} while (0)
405
406static int
407ccmp_encrypt(struct ieee80211_key *key, struct mbuf *m0, int hdrlen)
408{
409 struct ccmp_ctx *ctx = key->wk_private;
410 struct ieee80211_frame *wh;
411 struct mbuf *m = m0;
412 int data_len, i, space;
413 uint8_t aad[2 * AES_BLOCK_LEN], b0[AES_BLOCK_LEN], b[AES_BLOCK_LEN],
414 e[AES_BLOCK_LEN], s0[AES_BLOCK_LEN];
415 uint8_t *pos;
416
417 ctx->cc_ic->ic_stats.is_crypto_ccmp++;
418
419 wh = mtod(m, struct ieee80211_frame *);
420 data_len = m->m_pkthdr.len - (hdrlen + ccmp.ic_header);
421 ccmp_init_blocks(&ctx->cc_aes, wh, key->wk_keytsc,
422 data_len, b0, aad, b, s0);
423
424 i = 1;
425 pos = mtod(m, uint8_t *) + hdrlen + ccmp.ic_header;
426 /* NB: assumes header is entirely in first mbuf */
427 space = m->m_len - (hdrlen + ccmp.ic_header);
428 for (;;) {
429 if (space > data_len)
430 space = data_len;
431 /*
432 * Do full blocks.
433 */
434 while (space >= AES_BLOCK_LEN) {
435 CCMP_ENCRYPT(i, b, b0, pos, e, AES_BLOCK_LEN);
436 pos += AES_BLOCK_LEN, space -= AES_BLOCK_LEN;
437 data_len -= AES_BLOCK_LEN;
438 i++;
439 }
440 if (data_len <= 0) /* no more data */
441 break;
442 m = m->m_next;
443 if (m == NULL) { /* last buffer */
444 if (space != 0) {
445 /*
446 * Short last block.
447 */
448 CCMP_ENCRYPT(i, b, b0, pos, e, space);
449 }
450 break;
451 }
452 if (space != 0) {
453 uint8_t *pos_next;
454 int space_next;
455 int len, dl, sp;
456 struct mbuf *n;
457
458 /*
459 * Block straddles one or more mbufs, gather data
460 * into the block buffer b, apply the cipher, then
461 * scatter the results back into the mbuf chain.
462 * The buffer will automatically get space bytes
463 * of data at offset 0 copied in+out by the
464 * CCMP_ENCRYPT request so we must take care of
465 * the remaining data.
466 */
467 n = m;
468 dl = data_len;
469 sp = space;
470 for (;;) {
471 pos_next = mtod(n, uint8_t *);
472 len = min(dl, AES_BLOCK_LEN);
473 space_next = len > sp ? len - sp : 0;
474 if (n->m_len >= space_next) {
475 /*
476 * This mbuf has enough data; just grab
477 * what we need and stop.
478 */
479 xor_block(b+sp, pos_next, space_next);
480 break;
481 }
482 /*
483 * This mbuf's contents are insufficient,
484 * take 'em all and prepare to advance to
485 * the next mbuf.
486 */
487 xor_block(b+sp, pos_next, n->m_len);
488 sp += n->m_len, dl -= n->m_len;
489 n = n->m_next;
490 if (n == NULL)
491 break;
492 }
493
494 CCMP_ENCRYPT(i, b, b0, pos, e, space);
495
496 /* NB: just like above, but scatter data to mbufs */
497 dl = data_len;
498 sp = space;
499 for (;;) {
500 pos_next = mtod(m, uint8_t *);
501 len = min(dl, AES_BLOCK_LEN);
502 space_next = len > sp ? len - sp : 0;
503 if (m->m_len >= space_next) {
504 xor_block(pos_next, e+sp, space_next);
505 break;
506 }
507 xor_block(pos_next, e+sp, m->m_len);
508 sp += m->m_len, dl -= m->m_len;
509 m = m->m_next;
510 if (m == NULL)
511 goto done;
512 }
513 /*
514 * Do bookkeeping. m now points to the last mbuf
515 * we grabbed data from. We know we consumed a
516 * full block of data as otherwise we'd have hit
517 * the end of the mbuf chain, so deduct from data_len.
518 * Otherwise advance the block number (i) and setup
519 * pos+space to reflect contents of the new mbuf.
520 */
521 data_len -= AES_BLOCK_LEN;
522 i++;
523 pos = pos_next + space_next;
524 space = m->m_len - space_next;
525 } else {
526 /*
527 * Setup for next buffer.
528 */
529 pos = mtod(m, uint8_t *);
530 space = m->m_len;
531 }
532 }
533done:
534 /* tack on MIC */
535 xor_block(b, s0, ccmp.ic_trailer);
536 return m_append(m0, ccmp.ic_trailer, b);
537}
538#undef CCMP_ENCRYPT
539
540#define CCMP_DECRYPT(_i, _b, _b0, _pos, _a, _len) do { \
541 /* Decrypt, with counter */ \
542 _b0[14] = (_i >> 8) & 0xff; \
543 _b0[15] = _i & 0xff; \
544 rijndael_encrypt(&ctx->cc_aes, _b0, _b); \
545 xor_block(_pos, _b, _len); \
546 /* Authentication */ \
547 xor_block(_a, _pos, _len); \
548 rijndael_encrypt(&ctx->cc_aes, _a, _a); \
549} while (0)
550
551static int
552ccmp_decrypt(struct ieee80211_key *key, u_int64_t pn, struct mbuf *m, int hdrlen)
553{
554 struct ccmp_ctx *ctx = key->wk_private;
555 struct ieee80211_frame *wh;
556 uint8_t aad[2 * AES_BLOCK_LEN];
557 uint8_t b0[AES_BLOCK_LEN], b[AES_BLOCK_LEN], a[AES_BLOCK_LEN];
558 uint8_t mic[AES_BLOCK_LEN];
559 size_t data_len;
560 int i;
561 uint8_t *pos;
562 u_int space;
563
564 ctx->cc_ic->ic_stats.is_crypto_ccmp++;
565
566 wh = mtod(m, struct ieee80211_frame *);
567 data_len = m->m_pkthdr.len - (hdrlen + ccmp.ic_header + ccmp.ic_trailer);
568 ccmp_init_blocks(&ctx->cc_aes, wh, pn, data_len, b0, aad, a, b);
569 m_copydata(m, m->m_pkthdr.len - ccmp.ic_trailer, ccmp.ic_trailer, mic);
570 xor_block(mic, b, ccmp.ic_trailer);
571
572 i = 1;
573 pos = mtod(m, uint8_t *) + hdrlen + ccmp.ic_header;
574 space = m->m_len - (hdrlen + ccmp.ic_header);
575 for (;;) {
576 if (space > data_len)
577 space = data_len;
578 while (space >= AES_BLOCK_LEN) {
579 CCMP_DECRYPT(i, b, b0, pos, a, AES_BLOCK_LEN);
580 pos += AES_BLOCK_LEN, space -= AES_BLOCK_LEN;
581 data_len -= AES_BLOCK_LEN;
582 i++;
583 }
584 if (data_len <= 0) /* no more data */
585 break;
586 m = m->m_next;
587 if (m == NULL) { /* last buffer */
588 if (space != 0) /* short last block */
589 CCMP_DECRYPT(i, b, b0, pos, a, space);
590 break;
591 }
592 if (space != 0) {
593 uint8_t *pos_next;
594 u_int space_next;
595 u_int len;
596
597 /*
598 * Block straddles buffers, split references. We
599 * do not handle splits that require >2 buffers
600 * since rx'd frames are never badly fragmented
601 * because drivers typically recv in clusters.
602 */
603 pos_next = mtod(m, uint8_t *);
604 len = min(data_len, AES_BLOCK_LEN);
605 space_next = len > space ? len - space : 0;
606 IASSERT(m->m_len >= space_next,
607 ("not enough data in following buffer, "
608 "m_len %u need %u\n", m->m_len, space_next));
609
610 xor_block(b+space, pos_next, space_next);
611 CCMP_DECRYPT(i, b, b0, pos, a, space);
612 xor_block(pos_next, b+space, space_next);
613 data_len -= len;
614 i++;
615
616 pos = pos_next + space_next;
617 space = m->m_len - space_next;
618 } else {
619 /*
620 * Setup for next buffer.
621 */
622 pos = mtod(m, uint8_t *);
623 space = m->m_len;
624 }
625 }
626 if (memcmp(mic, a, ccmp.ic_trailer) != 0) {
627 IEEE80211_DPRINTF(ctx->cc_ic, IEEE80211_MSG_CRYPTO,
628 "[%s] AES-CCM decrypt failed; MIC mismatch\n",
629 ether_sprintf(wh->i_addr2));
630 ctx->cc_ic->ic_stats.is_rx_ccmpmic++;
631 return 0;
632 }
633 return 1;
634}
635#undef CCMP_DECRYPT
636
637IEEE80211_CRYPTO_SETUP(ccmp_register)
638{
639 ieee80211_crypto_register(&ccmp);
640}
641