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("$FreeBSD$"); 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); 667