1 /* 2 * Copyright 2009 Sun Microsystems, Inc. All rights reserved. 3 * Use is subject to license terms. 4 */ 5 6 /* 7 * Copyright (c) 2001 Atsushi Onoe 8 * Copyright (c) 2002-2008 Sam Leffler, Errno Consulting 9 * All rights reserved. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. The name of the author may not be used to endorse or promote products 20 * derived from this software without specific prior written permission. 21 * 22 * Alternatively, this software may be distributed under the terms of the 23 * GNU General Public License ("GPL") version 2 as published by the Free 24 * Software Foundation. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 27 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 28 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 29 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 30 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 31 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 35 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 36 */ 37 38 /* 39 * IEEE 802.11i CCMP crypto support. 40 */ 41 #include <sys/byteorder.h> 42 #include <sys/crypto/common.h> 43 #include <sys/crypto/api.h> 44 #include <sys/crc32.h> 45 #include <sys/random.h> 46 #include <sys/strsun.h> 47 #include "net80211_impl.h" 48 49 struct ccmp_ctx { 50 struct ieee80211com *cc_ic; /* for diagnostics */ 51 }; 52 53 #define AES_BLOCK_LEN 16 54 #define AES_NONCE_LEN 13 55 56 static void *ccmp_attach(struct ieee80211com *, struct ieee80211_key *); 57 static void ccmp_detach(struct ieee80211_key *); 58 static int ccmp_setkey(struct ieee80211_key *); 59 static int ccmp_encap(struct ieee80211_key *k, mblk_t *, uint8_t); 60 static int ccmp_decap(struct ieee80211_key *, mblk_t *, int); 61 static int ccmp_enmic(struct ieee80211_key *, mblk_t *, int); 62 static int ccmp_demic(struct ieee80211_key *, mblk_t *, int); 63 64 static int ccmp_encrypt(struct ieee80211_key *, mblk_t *, int); 65 static int ccmp_decrypt(struct ieee80211_key *, uint64_t pn, mblk_t *, int); 66 67 const struct ieee80211_cipher ccmp = { 68 "AES-CCM", 69 IEEE80211_CIPHER_AES_CCM, 70 IEEE80211_WEP_IVLEN + IEEE80211_WEP_KIDLEN + 71 IEEE80211_WEP_EXTIVLEN, 72 IEEE80211_WEP_MICLEN, 73 0, 74 ccmp_attach, 75 ccmp_detach, 76 ccmp_setkey, 77 ccmp_encap, 78 ccmp_decap, 79 ccmp_enmic, 80 ccmp_demic, 81 }; 82 83 /* ARGSUSED */ 84 static void * 85 ccmp_attach(struct ieee80211com *ic, struct ieee80211_key *k) 86 { 87 struct ccmp_ctx *ctx; 88 89 ctx = kmem_zalloc(sizeof (struct ccmp_ctx), KM_SLEEP); 90 if (ctx == NULL) 91 return (NULL); 92 93 ctx->cc_ic = ic; 94 return (ctx); 95 } 96 97 static void 98 ccmp_detach(struct ieee80211_key *k) 99 { 100 struct ccmp_ctx *ctx = k->wk_private; 101 102 if (ctx != NULL) 103 kmem_free(ctx, sizeof (struct ccmp_ctx)); 104 } 105 106 static int 107 ccmp_setkey(struct ieee80211_key *k) 108 { 109 if (k->wk_keylen != (128/NBBY)) 110 return (0); 111 112 return (1); 113 } 114 115 /* 116 * Add privacy headers appropriate for the specified key. 117 */ 118 static int 119 ccmp_encap(struct ieee80211_key *k, mblk_t *mp, uint8_t keyid) 120 { 121 struct ccmp_ctx *ctx = k->wk_private; 122 uint8_t *ivp; 123 int hdrlen; 124 125 hdrlen = ieee80211_hdrspace(ctx->cc_ic, mp->b_rptr); 126 /* 127 * Copy down 802.11 header and add the IV, KeyID, and ExtIV. 128 */ 129 ivp = mp->b_rptr; 130 ivp += hdrlen; 131 132 k->wk_keytsc++; /* wrap at 48 bits */ 133 ivp[0] = k->wk_keytsc >> 0; /* PN0 */ 134 ivp[1] = k->wk_keytsc >> 8; /* PN1 */ 135 ivp[2] = 0; /* Reserved */ 136 ivp[3] = keyid | IEEE80211_WEP_EXTIV; /* KeyID | ExtID */ 137 ivp[4] = k->wk_keytsc >> 16; /* PN2 */ 138 ivp[5] = k->wk_keytsc >> 24; /* PN3 */ 139 ivp[6] = k->wk_keytsc >> 32; /* PN4 */ 140 ivp[7] = k->wk_keytsc >> 40; /* PN5 */ 141 142 /* 143 * Finally, do software encrypt if neeed. 144 */ 145 if ((k->wk_flags & IEEE80211_KEY_SWCRYPT) && 146 !ccmp_encrypt(k, mp, hdrlen)) 147 return (0); 148 149 return (1); 150 } 151 152 /* 153 * Validate and strip privacy headers (and trailer) for a 154 * received frame. The specified key should be correct but 155 * is also verified. 156 */ 157 static int 158 ccmp_decap(struct ieee80211_key *k, mblk_t *mp, int hdrlen) 159 { 160 uint8_t *ivp; 161 uint64_t pn; 162 163 /* 164 * Header should have extended IV and sequence number; 165 * verify the former and validate the latter. 166 */ 167 ivp = mp->b_rptr + hdrlen; 168 if ((ivp[IEEE80211_WEP_IVLEN] & IEEE80211_WEP_EXTIV) == 0) { 169 /* 170 * No extended IV; discard frame. 171 */ 172 return (0); 173 } 174 175 pn = ieee80211_read_6(ivp[0], ivp[1], ivp[4], ivp[5], ivp[6], ivp[7]); 176 if (pn <= k->wk_keyrsc) { 177 /* 178 * Replay violation. 179 */ 180 return (0); 181 } 182 183 /* 184 * Check if the device handled the decrypt in hardware. 185 * If so we just strip the header; otherwise we need to 186 * handle the decrypt in software. Note that for the 187 * latter we leave the header in place for use in the 188 * decryption work. 189 */ 190 if ((k->wk_flags & IEEE80211_KEY_SWCRYPT) && 191 !ccmp_decrypt(k, pn, mp, hdrlen)) 192 return (0); 193 194 /* 195 * Copy up 802.11 header and strip crypto bits. 196 */ 197 (void) memmove(mp->b_rptr + ccmp.ic_header, mp->b_rptr, hdrlen); 198 mp->b_rptr += ccmp.ic_header; 199 mp->b_wptr -= ccmp.ic_trailer; 200 201 /* 202 * Ok to update rsc now. 203 */ 204 k->wk_keyrsc = pn; 205 206 return (1); 207 } 208 209 /* 210 * Add MIC to the frame as needed. 211 */ 212 /* ARGSUSED */ 213 static int 214 ccmp_enmic(struct ieee80211_key *k, mblk_t *mp, int force) 215 { 216 return (1); 217 } 218 219 /* 220 * Verify and strip MIC from the frame. 221 */ 222 /* ARGSUSED */ 223 static int 224 ccmp_demic(struct ieee80211_key *k, mblk_t *mp, int force) 225 { 226 return (1); 227 } 228 229 static int 230 aes_ccm_encrypt(CK_AES_CCM_PARAMS *cmparam, const uint8_t *key, int keylen, 231 const uint8_t *plaintext, int plain_len, 232 uint8_t *ciphertext, int cipher_len) 233 { 234 crypto_mechanism_t mech; 235 crypto_key_t crkey; 236 crypto_data_t d1, d2; 237 238 int rv; 239 240 ieee80211_dbg(IEEE80211_MSG_CRYPTO, 241 "aes_ccm_encrypt(len=%d, keylen=%d)", plain_len, keylen); 242 243 bzero(&crkey, sizeof (crkey)); 244 245 crkey.ck_format = CRYPTO_KEY_RAW; 246 crkey.ck_data = (char *)key; 247 /* keys are measured in bits, not bytes, so multiply by 8 */ 248 crkey.ck_length = keylen * 8; 249 250 mech.cm_type = crypto_mech2id(SUN_CKM_AES_CCM); 251 mech.cm_param = (caddr_t)cmparam; 252 mech.cm_param_len = sizeof (CK_AES_CCM_PARAMS); 253 254 #if defined(_LP64) 255 ieee80211_dbg(IEEE80211_MSG_CRYPTO, "cm_type=%lx", mech.cm_type); 256 #else 257 ieee80211_dbg(IEEE80211_MSG_CRYPTO, "cm_type=%llx", mech.cm_type); 258 #endif 259 260 bzero(&d1, sizeof (d1)); 261 bzero(&d2, sizeof (d2)); 262 263 d1.cd_format = CRYPTO_DATA_RAW; 264 d1.cd_offset = 0; 265 d1.cd_length = plain_len; 266 d1.cd_raw.iov_base = (char *)plaintext; 267 d1.cd_raw.iov_len = plain_len; 268 269 d2.cd_format = CRYPTO_DATA_RAW; 270 d2.cd_offset = 0; 271 d2.cd_length = cipher_len; 272 d2.cd_raw.iov_base = (char *)ciphertext; 273 d2.cd_raw.iov_len = cipher_len; 274 275 276 rv = crypto_encrypt(&mech, &d1, &crkey, NULL, &d2, NULL); 277 if (rv != CRYPTO_SUCCESS) 278 ieee80211_err("aes_ccm_encrypt failed (%x)", rv); 279 return (rv); 280 } 281 282 static int 283 aes_ccm_decrypt(CK_AES_CCM_PARAMS *cmparam, const uint8_t *key, int keylen, 284 const uint8_t *ciphertext, int cipher_len, 285 uint8_t *plaintext, int plain_len) 286 { 287 crypto_mechanism_t mech; 288 crypto_key_t crkey; 289 crypto_data_t d1, d2; 290 291 int rv; 292 293 ieee80211_dbg(IEEE80211_MSG_CRYPTO, 294 "aes_ccm_decrypt(len=%d, keylen=%d)", cipher_len, keylen); 295 296 bzero(&crkey, sizeof (crkey)); 297 298 crkey.ck_format = CRYPTO_KEY_RAW; 299 crkey.ck_data = (char *)key; 300 /* keys are measured in bits, not bytes, so multiply by 8 */ 301 crkey.ck_length = keylen * 8; 302 303 mech.cm_type = crypto_mech2id(SUN_CKM_AES_CCM); 304 mech.cm_param = (caddr_t)cmparam; 305 mech.cm_param_len = sizeof (CK_AES_CCM_PARAMS); 306 307 #if defined(_LP64) 308 ieee80211_dbg(IEEE80211_MSG_CRYPTO, "cm_type=%lx", mech.cm_type); 309 #else 310 ieee80211_dbg(IEEE80211_MSG_CRYPTO, "cm_type=%llx", mech.cm_type); 311 #endif 312 313 bzero(&d1, sizeof (d1)); 314 bzero(&d2, sizeof (d2)); 315 316 d1.cd_format = CRYPTO_DATA_RAW; 317 d1.cd_offset = 0; 318 d1.cd_length = cipher_len; 319 d1.cd_raw.iov_base = (char *)ciphertext; 320 d1.cd_raw.iov_len = cipher_len; 321 322 d2.cd_format = CRYPTO_DATA_RAW; 323 d2.cd_offset = 0; 324 d2.cd_length = plain_len; 325 d2.cd_raw.iov_base = (char *)plaintext; 326 d2.cd_raw.iov_len = plain_len; 327 328 329 rv = crypto_decrypt(&mech, &d1, &crkey, NULL, &d2, NULL); 330 if (rv != CRYPTO_SUCCESS) 331 ieee80211_err("aes_ccm_decrypt failed (%x)", rv); 332 return (rv); 333 } 334 335 /* 336 * For the avoidance of doubt, except that if any license choice other 337 * than GPL or LGPL is available it will apply instead, Sun elects to 338 * use only the General Public License version 2 (GPLv2) at this time 339 * for any software where a choice of GPL license versions is made 340 * available with the language indicating that GPLv2 or any later 341 * version may be used, or where a choice of which version of the GPL 342 * is applied is otherwise unspecified. 343 */ 344 345 /* 346 * Host AP crypt: host-based CCMP encryption implementation for Host AP driver 347 * 348 * Copyright (c) 2003-2004, Jouni Malinen <jkmaline@cc.hut.fi> 349 * 350 * This program is free software; you can redistribute it and/or modify 351 * it under the terms of the GNU General Public License version 2 as 352 * published by the Free Software Foundation. See README and COPYING for 353 * more details. 354 * 355 * Alternatively, this software may be distributed under the terms of BSD 356 * license. 357 */ 358 359 static void 360 ccmp_init(struct ieee80211_frame *wh, uint64_t pn, size_t dlen, 361 uint8_t b0[AES_BLOCK_LEN], uint8_t aad[2 * AES_BLOCK_LEN]) 362 { 363 /* 364 * CCM Initial Block: 365 * Flag (Include authentication header, M=3 (8-octet MIC), 366 * L=1 (2-octet Dlen)) 367 * Nonce: 0x00 | A2 | PN 368 * Dlen 369 */ 370 b0[0] = 0x59; 371 /* b0[1] set below */ 372 IEEE80211_ADDR_COPY(b0 + 2, wh->i_addr2); 373 b0[8] = pn >> 40; 374 b0[9] = pn >> 32; 375 b0[10] = pn >> 24; 376 b0[11] = pn >> 16; 377 b0[12] = pn >> 8; 378 b0[13] = (uint8_t)(pn >> 0); 379 b0[14] = (dlen >> 8) & 0xff; 380 b0[15] = dlen & 0xff; 381 382 /* 383 * AAD: 384 * FC with bits 4..6 and 11..13 masked to zero; 14 is always one 385 * A1 | A2 | A3 386 * SC with bits 4..15 (seq#) masked to zero 387 * A4 (if present) 388 * QC (if present) 389 */ 390 aad[0] = 0; /* AAD length >> 8 */ 391 /* aad[1] set below */ 392 aad[2] = wh->i_fc[0] & 0x8f; /* magic #s */ 393 aad[3] = wh->i_fc[1] & 0xc7; /* magic #s */ 394 /* we know 3 addresses are contiguous */ 395 (void) memcpy(aad + 4, wh->i_addr1, 3 * IEEE80211_ADDR_LEN); 396 aad[22] = wh->i_seq[0] & IEEE80211_SEQ_FRAG_MASK; 397 aad[23] = 0; /* all bits masked */ 398 /* 399 * Construct variable-length portion of AAD based 400 * on whether this is a 4-address frame/QOS frame. 401 * We always zero-pad to 32 bytes before running it 402 * through the cipher. 403 * 404 * We also fill in the priority bits of the CCM 405 * initial block as we know whether or not we have 406 * a QOS frame. 407 */ 408 if (IEEE80211_QOS_HAS_SEQ(wh)) { 409 struct ieee80211_qosframe *qwh = 410 (struct ieee80211_qosframe *)wh; 411 aad[24] = qwh->i_qos[0] & 0x0f; /* just priority bits */ 412 aad[25] = 0; 413 b0[1] = aad[24]; 414 aad[1] = 22 + 2; 415 } else { 416 *(uint16_t *)&aad[24] = 0; 417 b0[1] = 0; 418 aad[1] = 22; 419 } 420 *(uint16_t *)&aad[26] = 0; 421 *(uint32_t *)&aad[28] = 0; 422 } 423 424 static int 425 ccmp_encrypt(struct ieee80211_key *key, mblk_t *mp, int hdrlen) 426 { 427 struct ieee80211_frame *wh; 428 int rv, data_len; 429 uint8_t aad[2 * AES_BLOCK_LEN], b0[AES_BLOCK_LEN]; 430 uint8_t *pos; 431 CK_AES_CCM_PARAMS cmparam; 432 433 wh = (struct ieee80211_frame *)mp->b_rptr; 434 data_len = MBLKL(mp) - (hdrlen + ccmp.ic_header); 435 pos = mp->b_rptr + hdrlen + ccmp.ic_header; 436 437 ccmp_init(wh, key->wk_keytsc, data_len, b0, aad); 438 439 cmparam.ulMACSize = IEEE80211_WEP_MICLEN; 440 cmparam.ulNonceSize = AES_NONCE_LEN; /* N size */ 441 cmparam.ulAuthDataSize = aad[1]; /* A size */ 442 cmparam.ulDataSize = data_len; /* data length; */ 443 cmparam.nonce = &b0[1]; /* N */ 444 cmparam.authData = &aad[2]; /* A */ 445 446 rv = aes_ccm_encrypt(&cmparam, 447 key->wk_key, key->wk_keylen, 448 pos, data_len, pos, data_len + IEEE80211_WEP_MICLEN); 449 450 mp->b_wptr += ccmp.ic_trailer; 451 452 return ((rv == CRYPTO_SUCCESS)? 1 : 0); 453 } 454 455 static int 456 ccmp_decrypt(struct ieee80211_key *key, uint64_t pn, mblk_t *mp, int hdrlen) 457 { 458 struct ieee80211_frame *wh; 459 int rv, data_len; 460 uint8_t aad[2 * AES_BLOCK_LEN], b0[AES_BLOCK_LEN]; 461 uint8_t *pos; 462 CK_AES_CCM_PARAMS cmparam; 463 464 wh = (struct ieee80211_frame *)mp->b_rptr; 465 data_len = MBLKL(mp) - (hdrlen + ccmp.ic_header); 466 pos = mp->b_rptr + hdrlen + ccmp.ic_header; 467 468 ccmp_init(wh, pn, data_len, b0, aad); 469 470 cmparam.ulMACSize = IEEE80211_WEP_MICLEN; /* MIC = 8 */ 471 cmparam.ulNonceSize = AES_NONCE_LEN; /* N size */ 472 cmparam.ulAuthDataSize = aad[1]; /* A size */ 473 cmparam.ulDataSize = data_len; 474 cmparam.nonce = &b0[1]; /* N */ 475 cmparam.authData = &aad[2]; /* A */ 476 477 rv = aes_ccm_decrypt(&cmparam, 478 key->wk_key, key->wk_keylen, pos, data_len, pos, data_len); 479 480 return ((rv == CRYPTO_SUCCESS)? 1 : 0); 481 } 482