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 __FBSDID("$FreeBSD: releng/6.2/sys/net80211/ieee80211_crypto_ccmp.c 153653 2005-12-22 19:02:08Z sam $");
34
35 /*
36 * IEEE 802.11i AES-CCMP crypto support.
37 *
38 * Part of this module is derived from similar code in the Host
39 * AP driver. The code is used with the consent of the author and
40 * it's license is included below.
41 */
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/mbuf.h>
45 #include <sys/malloc.h>
46 #include <sys/kernel.h>
47 #include <sys/module.h>
48
49 #include <sys/socket.h>
50
51 #include <net/if.h>
52 #include <net/if_media.h>
53 #include <net/ethernet.h>
54
55 #include <net80211/ieee80211_var.h>
56
57 #include <crypto/rijndael/rijndael.h>
58
59 #define AES_BLOCK_LEN 16
60
61 struct ccmp_ctx {
62 struct ieee80211com *cc_ic; /* for diagnostics */
63 rijndael_ctx cc_aes;
64 };
65
66 static void *ccmp_attach(struct ieee80211com *, struct ieee80211_key *);
67 static void ccmp_detach(struct ieee80211_key *);
68 static int ccmp_setkey(struct ieee80211_key *);
69 static int ccmp_encap(struct ieee80211_key *k, struct mbuf *, u_int8_t keyid);
70 static int ccmp_decap(struct ieee80211_key *, struct mbuf *, int);
71 static int ccmp_enmic(struct ieee80211_key *, struct mbuf *, int);
72 static int ccmp_demic(struct ieee80211_key *, struct mbuf *, int);
73
74 static const struct ieee80211_cipher ccmp = {
75 .ic_name = "AES-CCM",
76 .ic_cipher = IEEE80211_CIPHER_AES_CCM,
77 .ic_header = IEEE80211_WEP_IVLEN + IEEE80211_WEP_KIDLEN +
78 IEEE80211_WEP_EXTIVLEN,
79 .ic_trailer = IEEE80211_WEP_MICLEN,
80 .ic_miclen = 0,
81 .ic_attach = ccmp_attach,
82 .ic_detach = ccmp_detach,
83 .ic_setkey = ccmp_setkey,
84 .ic_encap = ccmp_encap,
85 .ic_decap = ccmp_decap,
86 .ic_enmic = ccmp_enmic,
87 .ic_demic = ccmp_demic,
88 };
89
90 static int ccmp_encrypt(struct ieee80211_key *, struct mbuf *, int hdrlen);
91 static int ccmp_decrypt(struct ieee80211_key *, u_int64_t pn,
92 struct mbuf *, int hdrlen);
93
94 /* number of references from net80211 layer */
95 static int nrefs = 0;
96
97 static void *
98 ccmp_attach(struct ieee80211com *ic, struct ieee80211_key *k)
99 {
100 struct ccmp_ctx *ctx;
101
102 MALLOC(ctx, struct ccmp_ctx *, sizeof(struct ccmp_ctx),
103 M_DEVBUF, M_NOWAIT | M_ZERO);
104 if (ctx == NULL) {
105 ic->ic_stats.is_crypto_nomem++;
106 return NULL;
107 }
108 ctx->cc_ic = ic;
109 nrefs++; /* NB: we assume caller locking */
110 return ctx;
111 }
112
113 static void
114 ccmp_detach(struct ieee80211_key *k)
115 {
116 struct ccmp_ctx *ctx = k->wk_private;
117
118 FREE(ctx, M_DEVBUF);
119 KASSERT(nrefs > 0, ("imbalanced attach/detach"));
120 nrefs--; /* NB: we assume caller locking */
121 }
122
123 static int
124 ccmp_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 */
142 static int
143 ccmp_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 */
185 static int
186 ccmp_enmic(struct ieee80211_key *k, struct mbuf *m, int force)
187 {
188
189 return 1;
190 }
191
192 static __inline uint64_t
193 READ_6(uint8_t b0, uint8_t b1, uint8_t b2, uint8_t b3, uint8_t b4, uint8_t b5)
194 {
195 uint32_t iv32 = (b0 << 0) | (b1 << 8) | (b2 << 16) | (b3 << 24);
196 uint16_t iv16 = (b4 << 0) | (b5 << 8);
197 return (((uint64_t)iv16) << 32) | iv32;
198 }
199
200 /*
201 * Validate and strip privacy headers (and trailer) for a
202 * received frame. The specified key should be correct but
203 * is also verified.
204 */
205 static int
206 ccmp_decap(struct ieee80211_key *k, struct mbuf *m, int hdrlen)
207 {
208 struct ccmp_ctx *ctx = k->wk_private;
209 struct ieee80211_frame *wh;
210 uint8_t *ivp;
211 uint64_t pn;
212
213 /*
214 * Header should have extended IV and sequence number;
215 * verify the former and validate the latter.
216 */
217 wh = mtod(m, struct ieee80211_frame *);
218 ivp = mtod(m, uint8_t *) + hdrlen;
219 if ((ivp[IEEE80211_WEP_IVLEN] & IEEE80211_WEP_EXTIV) == 0) {
220 /*
221 * No extended IV; discard frame.
222 */
223 IEEE80211_DPRINTF(ctx->cc_ic, IEEE80211_MSG_CRYPTO,
224 "[%s] Missing ExtIV for AES-CCM cipher\n",
225 ether_sprintf(wh->i_addr2));
226 ctx->cc_ic->ic_stats.is_rx_ccmpformat++;
227 return 0;
228 }
229 pn = READ_6(ivp[0], ivp[1], ivp[4], ivp[5], ivp[6], ivp[7]);
230 if (pn <= k->wk_keyrsc) {
231 /*
232 * Replay violation.
233 */
234 ieee80211_notify_replay_failure(ctx->cc_ic, wh, k, pn);
235 ctx->cc_ic->ic_stats.is_rx_ccmpreplay++;
236 return 0;
237 }
238
239 /*
240 * Check if the device handled the decrypt in hardware.
241 * If so we just strip the header; otherwise we need to
242 * handle the decrypt in software. Note that for the
243 * latter we leave the header in place for use in the
244 * decryption work.
245 */
246 if ((k->wk_flags & IEEE80211_KEY_SWCRYPT) &&
247 !ccmp_decrypt(k, pn, m, hdrlen))
248 return 0;
249
250 /*
251 * Copy up 802.11 header and strip crypto bits.
252 */
253 ovbcopy(mtod(m, void *), mtod(m, u_int8_t *) + ccmp.ic_header, hdrlen);
254 m_adj(m, ccmp.ic_header);
255 m_adj(m, -ccmp.ic_trailer);
256
257 /*
258 * Ok to update rsc now.
259 */
260 k->wk_keyrsc = pn;
261
262 return 1;
263 }
264
265 /*
266 * Verify and strip MIC from the frame.
267 */
268 static int
269 ccmp_demic(struct ieee80211_key *k, struct mbuf *m, int force)
270 {
271 return 1;
272 }
273
274 static __inline void
275 xor_block(uint8_t *b, const uint8_t *a, size_t len)
276 {
277 int i;
278 for (i = 0; i < len; i++)
279 b[i] ^= a[i];
280 }
281
282 /*
283 * Host AP crypt: host-based CCMP encryption implementation for Host AP driver
284 *
285 * Copyright (c) 2003-2004, Jouni Malinen <jkmaline@cc.hut.fi>
286 *
287 * This program is free software; you can redistribute it and/or modify
288 * it under the terms of the GNU General Public License version 2 as
289 * published by the Free Software Foundation. See README and COPYING for
290 * more details.
291 *
292 * Alternatively, this software may be distributed under the terms of BSD
293 * license.
294 */
295
296 static void
297 ccmp_init_blocks(rijndael_ctx *ctx, struct ieee80211_frame *wh,
298 u_int64_t pn, size_t dlen,
299 uint8_t b0[AES_BLOCK_LEN], uint8_t aad[2 * AES_BLOCK_LEN],
300 uint8_t auth[AES_BLOCK_LEN], uint8_t s0[AES_BLOCK_LEN])
301 {
302 #define IS_4ADDRESS(wh) \
303 ((wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) == IEEE80211_FC1_DIR_DSTODS)
304 #define IS_QOS_DATA(wh) IEEE80211_QOS_HAS_SEQ(wh)
305
306 /* CCM Initial Block:
307 * Flag (Include authentication header, M=3 (8-octet MIC),
308 * L=1 (2-octet Dlen))
309 * Nonce: 0x00 | A2 | PN
310 * Dlen */
311 b0[0] = 0x59;
312 /* NB: b0[1] set below */
313 IEEE80211_ADDR_COPY(b0 + 2, wh->i_addr2);
314 b0[8] = pn >> 40;
315 b0[9] = pn >> 32;
316 b0[10] = pn >> 24;
317 b0[11] = pn >> 16;
318 b0[12] = pn >> 8;
319 b0[13] = pn >> 0;
320 b0[14] = (dlen >> 8) & 0xff;
321 b0[15] = dlen & 0xff;
322
323 /* AAD:
324 * FC with bits 4..6 and 11..13 masked to zero; 14 is always one
325 * A1 | A2 | A3
326 * SC with bits 4..15 (seq#) masked to zero
327 * A4 (if present)
328 * QC (if present)
329 */
330 aad[0] = 0; /* AAD length >> 8 */
331 /* NB: aad[1] set below */
332 aad[2] = wh->i_fc[0] & 0x8f; /* XXX magic #s */
333 aad[3] = wh->i_fc[1] & 0xc7; /* XXX magic #s */
334 /* NB: we know 3 addresses are contiguous */
335 memcpy(aad + 4, wh->i_addr1, 3 * IEEE80211_ADDR_LEN);
336 aad[22] = wh->i_seq[0] & IEEE80211_SEQ_FRAG_MASK;
337 aad[23] = 0; /* all bits masked */
338 /*
339 * Construct variable-length portion of AAD based
340 * on whether this is a 4-address frame/QOS frame.
341 * We always zero-pad to 32 bytes before running it
342 * through the cipher.
343 *
344 * We also fill in the priority bits of the CCM
345 * initial block as we know whether or not we have
346 * a QOS frame.
347 */
348 if (IS_4ADDRESS(wh)) {
349 IEEE80211_ADDR_COPY(aad + 24,
350 ((struct ieee80211_frame_addr4 *)wh)->i_addr4);
351 if (IS_QOS_DATA(wh)) {
352 struct ieee80211_qosframe_addr4 *qwh4 =
353 (struct ieee80211_qosframe_addr4 *) wh;
354 aad[30] = qwh4->i_qos[0] & 0x0f;/* just priority bits */
355 aad[31] = 0;
356 b0[1] = aad[30];
357 aad[1] = 22 + IEEE80211_ADDR_LEN + 2;
358 } else {
359 *(u_int16_t *)&aad[30] = 0;
360 b0[1] = 0;
361 aad[1] = 22 + IEEE80211_ADDR_LEN;
362 }
363 } else {
364 if (IS_QOS_DATA(wh)) {
365 struct ieee80211_qosframe *qwh =
366 (struct ieee80211_qosframe*) wh;
367 aad[24] = qwh->i_qos[0] & 0x0f; /* just priority bits */
368 aad[25] = 0;
369 b0[1] = aad[24];
370 aad[1] = 22 + 2;
371 } else {
372 *(u_int16_t *)&aad[24] = 0;
373 b0[1] = 0;
374 aad[1] = 22;
375 }
376 *(u_int16_t *)&aad[26] = 0;
377 *(u_int32_t *)&aad[28] = 0;
378 }
379
380 /* Start with the first block and AAD */
381 rijndael_encrypt(ctx, b0, auth);
382 xor_block(auth, aad, AES_BLOCK_LEN);
383 rijndael_encrypt(ctx, auth, auth);
384 xor_block(auth, &aad[AES_BLOCK_LEN], AES_BLOCK_LEN);
385 rijndael_encrypt(ctx, auth, auth);
386 b0[0] &= 0x07;
387 b0[14] = b0[15] = 0;
388 rijndael_encrypt(ctx, b0, s0);
389 #undef IS_QOS_DATA
390 #undef IS_4ADDRESS
391 }
392
393 #define CCMP_ENCRYPT(_i, _b, _b0, _pos, _e, _len) do { \
394 /* Authentication */ \
395 xor_block(_b, _pos, _len); \
396 rijndael_encrypt(&ctx->cc_aes, _b, _b); \
397 /* Encryption, with counter */ \
398 _b0[14] = (_i >> 8) & 0xff; \
399 _b0[15] = _i & 0xff; \
400 rijndael_encrypt(&ctx->cc_aes, _b0, _e); \
401 xor_block(_pos, _e, _len); \
402 } while (0)
403
404 static int
405 ccmp_encrypt(struct ieee80211_key *key, struct mbuf *m0, int hdrlen)
406 {
407 struct ccmp_ctx *ctx = key->wk_private;
408 struct ieee80211_frame *wh;
409 struct mbuf *m = m0;
410 int data_len, i, space;
411 uint8_t aad[2 * AES_BLOCK_LEN], b0[AES_BLOCK_LEN], b[AES_BLOCK_LEN],
412 e[AES_BLOCK_LEN], s0[AES_BLOCK_LEN];
413 uint8_t *pos;
414
415 ctx->cc_ic->ic_stats.is_crypto_ccmp++;
416
417 wh = mtod(m, struct ieee80211_frame *);
418 data_len = m->m_pkthdr.len - (hdrlen + ccmp.ic_header);
419 ccmp_init_blocks(&ctx->cc_aes, wh, key->wk_keytsc,
420 data_len, b0, aad, b, s0);
421
422 i = 1;
423 pos = mtod(m, uint8_t *) + hdrlen + ccmp.ic_header;
424 /* NB: assumes header is entirely in first mbuf */
425 space = m->m_len - (hdrlen + ccmp.ic_header);
426 for (;;) {
427 if (space > data_len)
428 space = data_len;
429 /*
430 * Do full blocks.
431 */
432 while (space >= AES_BLOCK_LEN) {
433 CCMP_ENCRYPT(i, b, b0, pos, e, AES_BLOCK_LEN);
434 pos += AES_BLOCK_LEN, space -= AES_BLOCK_LEN;
435 data_len -= AES_BLOCK_LEN;
436 i++;
437 }
438 if (data_len <= 0) /* no more data */
439 break;
440 m = m->m_next;
441 if (m == NULL) { /* last buffer */
442 if (space != 0) {
443 /*
444 * Short last block.
445 */
446 CCMP_ENCRYPT(i, b, b0, pos, e, space);
447 }
448 break;
449 }
450 if (space != 0) {
451 uint8_t *pos_next;
452 int space_next;
453 int len, dl, sp;
454 struct mbuf *n;
455
456 /*
457 * Block straddles one or more mbufs, gather data
458 * into the block buffer b, apply the cipher, then
459 * scatter the results back into the mbuf chain.
460 * The buffer will automatically get space bytes
461 * of data at offset 0 copied in+out by the
462 * CCMP_ENCRYPT request so we must take care of
463 * the remaining data.
464 */
465 n = m;
466 dl = data_len;
467 sp = space;
468 for (;;) {
469 pos_next = mtod(n, uint8_t *);
470 len = min(dl, AES_BLOCK_LEN);
471 space_next = len > sp ? len - sp : 0;
472 if (n->m_len >= space_next) {
473 /*
474 * This mbuf has enough data; just grab
475 * what we need and stop.
476 */
477 xor_block(b+sp, pos_next, space_next);
478 break;
479 }
480 /*
481 * This mbuf's contents are insufficient,
482 * take 'em all and prepare to advance to
483 * the next mbuf.
484 */
485 xor_block(b+sp, pos_next, n->m_len);
486 sp += n->m_len, dl -= n->m_len;
487 n = n->m_next;
488 if (n == NULL)
489 break;
490 }
491
492 CCMP_ENCRYPT(i, b, b0, pos, e, space);
493
494 /* NB: just like above, but scatter data to mbufs */
495 dl = data_len;
496 sp = space;
497 for (;;) {
498 pos_next = mtod(m, uint8_t *);
499 len = min(dl, AES_BLOCK_LEN);
500 space_next = len > sp ? len - sp : 0;
501 if (m->m_len >= space_next) {
502 xor_block(pos_next, e+sp, space_next);
503 break;
504 }
505 xor_block(pos_next, e+sp, m->m_len);
506 sp += m->m_len, dl -= m->m_len;
507 m = m->m_next;
508 if (m == NULL)
509 goto done;
510 }
511 /*
512 * Do bookkeeping. m now points to the last mbuf
513 * we grabbed data from. We know we consumed a
514 * full block of data as otherwise we'd have hit
515 * the end of the mbuf chain, so deduct from data_len.
516 * Otherwise advance the block number (i) and setup
517 * pos+space to reflect contents of the new mbuf.
518 */
519 data_len -= AES_BLOCK_LEN;
520 i++;
521 pos = pos_next + space_next;
522 space = m->m_len - space_next;
523 } else {
524 /*
525 * Setup for next buffer.
526 */
527 pos = mtod(m, uint8_t *);
528 space = m->m_len;
529 }
530 }
531 done:
532 /* tack on MIC */
533 xor_block(b, s0, ccmp.ic_trailer);
534 return m_append(m0, ccmp.ic_trailer, b);
535 }
536 #undef CCMP_ENCRYPT
537
538 #define CCMP_DECRYPT(_i, _b, _b0, _pos, _a, _len) do { \
539 /* Decrypt, with counter */ \
540 _b0[14] = (_i >> 8) & 0xff; \
541 _b0[15] = _i & 0xff; \
542 rijndael_encrypt(&ctx->cc_aes, _b0, _b); \
543 xor_block(_pos, _b, _len); \
544 /* Authentication */ \
545 xor_block(_a, _pos, _len); \
546 rijndael_encrypt(&ctx->cc_aes, _a, _a); \
547 } while (0)
548
549 static int
550 ccmp_decrypt(struct ieee80211_key *key, u_int64_t pn, struct mbuf *m, int hdrlen)
551 {
552 struct ccmp_ctx *ctx = key->wk_private;
553 struct ieee80211_frame *wh;
554 uint8_t aad[2 * AES_BLOCK_LEN];
555 uint8_t b0[AES_BLOCK_LEN], b[AES_BLOCK_LEN], a[AES_BLOCK_LEN];
556 uint8_t mic[AES_BLOCK_LEN];
557 size_t data_len;
558 int i;
559 uint8_t *pos;
560 u_int space;
561
562 ctx->cc_ic->ic_stats.is_crypto_ccmp++;
563
564 wh = mtod(m, struct ieee80211_frame *);
565 data_len = m->m_pkthdr.len - (hdrlen + ccmp.ic_header + ccmp.ic_trailer);
566 ccmp_init_blocks(&ctx->cc_aes, wh, pn, data_len, b0, aad, a, b);
567 m_copydata(m, m->m_pkthdr.len - ccmp.ic_trailer, ccmp.ic_trailer, mic);
568 xor_block(mic, b, ccmp.ic_trailer);
569
570 i = 1;
571 pos = mtod(m, uint8_t *) + hdrlen + ccmp.ic_header;
572 space = m->m_len - (hdrlen + ccmp.ic_header);
573 for (;;) {
574 if (space > data_len)
575 space = data_len;
576 while (space >= AES_BLOCK_LEN) {
577 CCMP_DECRYPT(i, b, b0, pos, a, AES_BLOCK_LEN);
578 pos += AES_BLOCK_LEN, space -= AES_BLOCK_LEN;
579 data_len -= AES_BLOCK_LEN;
580 i++;
581 }
582 if (data_len <= 0) /* no more data */
583 break;
584 m = m->m_next;
585 if (m == NULL) { /* last buffer */
586 if (space != 0) /* short last block */
587 CCMP_DECRYPT(i, b, b0, pos, a, space);
588 break;
589 }
590 if (space != 0) {
591 uint8_t *pos_next;
592 u_int space_next;
593 u_int len;
594
595 /*
596 * Block straddles buffers, split references. We
597 * do not handle splits that require >2 buffers
598 * since rx'd frames are never badly fragmented
599 * because drivers typically recv in clusters.
600 */
601 pos_next = mtod(m, uint8_t *);
602 len = min(data_len, AES_BLOCK_LEN);
603 space_next = len > space ? len - space : 0;
604 KASSERT(m->m_len >= space_next,
605 ("not enough data in following buffer, "
606 "m_len %u need %u\n", m->m_len, space_next));
607
608 xor_block(b+space, pos_next, space_next);
609 CCMP_DECRYPT(i, b, b0, pos, a, space);
610 xor_block(pos_next, b+space, space_next);
611 data_len -= len;
612 i++;
613
614 pos = pos_next + space_next;
615 space = m->m_len - space_next;
616 } else {
617 /*
618 * Setup for next buffer.
619 */
620 pos = mtod(m, uint8_t *);
621 space = m->m_len;
622 }
623 }
624 if (memcmp(mic, a, ccmp.ic_trailer) != 0) {
625 IEEE80211_DPRINTF(ctx->cc_ic, IEEE80211_MSG_CRYPTO,
626 "[%s] AES-CCM decrypt failed; MIC mismatch\n",
627 ether_sprintf(wh->i_addr2));
628 ctx->cc_ic->ic_stats.is_rx_ccmpmic++;
629 return 0;
630 }
631 return 1;
632 }
633 #undef CCMP_DECRYPT
634
635 /*
636 * Module glue.
637 */
638 static int
639 ccmp_modevent(module_t mod, int type, void *unused)
640 {
641 switch (type) {
642 case MOD_LOAD:
643 ieee80211_crypto_register(&ccmp);
644 return 0;
645 case MOD_UNLOAD:
646 case MOD_QUIESCE:
647 if (nrefs) {
648 printf("wlan_ccmp: still in use (%u dynamic refs)\n",
649 nrefs);
650 return EBUSY;
651 }
652 if (type == MOD_UNLOAD)
653 ieee80211_crypto_unregister(&ccmp);
654 return 0;
655 }
656 return EINVAL;
657 }
658
659 static moduledata_t ccmp_mod = {
660 "wlan_ccmp",
661 ccmp_modevent,
662 0
663 };
664 DECLARE_MODULE(wlan_ccmp, ccmp_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
665 MODULE_VERSION(wlan_ccmp, 1);
666 MODULE_DEPEND(wlan_ccmp, wlan, 1, 1, 1);
Cache object: a8d44e9b49c034be5385ed2b25ec71e1
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