1 /* 2 * Copyright 2002-2004, Instant802 Networks, Inc. 3 * Copyright 2008, Jouni Malinen <j@w1.fi> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 as 7 * published by the Free Software Foundation. 8 */ 9 10 #include <linux/netdevice.h> 11 #include <linux/types.h> 12 #include <linux/skbuff.h> 13 #include <linux/compiler.h> 14 #include <linux/ieee80211.h> 15 #include <linux/gfp.h> 16 #include <asm/unaligned.h> 17 #include <net/mac80211.h> 18 #include <crypto/aes.h> 19 20 #include "ieee80211_i.h" 21 #include "michael.h" 22 #include "tkip.h" 23 #include "aes_ccm.h" 24 #include "aes_cmac.h" 25 #include "aes_gmac.h" 26 #include "aes_gcm.h" 27 #include "wpa.h" 28 29 ieee80211_tx_result 30 ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx) 31 { 32 u8 *data, *key, *mic; 33 size_t data_len; 34 unsigned int hdrlen; 35 struct ieee80211_hdr *hdr; 36 struct sk_buff *skb = tx->skb; 37 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 38 int tail; 39 40 hdr = (struct ieee80211_hdr *)skb->data; 41 if (!tx->key || tx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP || 42 skb->len < 24 || !ieee80211_is_data_present(hdr->frame_control)) 43 return TX_CONTINUE; 44 45 hdrlen = ieee80211_hdrlen(hdr->frame_control); 46 if (skb->len < hdrlen) 47 return TX_DROP; 48 49 data = skb->data + hdrlen; 50 data_len = skb->len - hdrlen; 51 52 if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) { 53 /* Need to use software crypto for the test */ 54 info->control.hw_key = NULL; 55 } 56 57 if (info->control.hw_key && 58 (info->flags & IEEE80211_TX_CTL_DONTFRAG || 59 tx->local->ops->set_frag_threshold) && 60 !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) { 61 /* hwaccel - with no need for SW-generated MMIC */ 62 return TX_CONTINUE; 63 } 64 65 tail = MICHAEL_MIC_LEN; 66 if (!info->control.hw_key) 67 tail += IEEE80211_TKIP_ICV_LEN; 68 69 if (WARN(skb_tailroom(skb) < tail || 70 skb_headroom(skb) < IEEE80211_TKIP_IV_LEN, 71 "mmic: not enough head/tail (%d/%d,%d/%d)\n", 72 skb_headroom(skb), IEEE80211_TKIP_IV_LEN, 73 skb_tailroom(skb), tail)) 74 return TX_DROP; 75 76 key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY]; 77 mic = skb_put(skb, MICHAEL_MIC_LEN); 78 michael_mic(key, hdr, data, data_len, mic); 79 if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) 80 mic[0]++; 81 82 return TX_CONTINUE; 83 } 84 85 86 ieee80211_rx_result 87 ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx) 88 { 89 u8 *data, *key = NULL; 90 size_t data_len; 91 unsigned int hdrlen; 92 u8 mic[MICHAEL_MIC_LEN]; 93 struct sk_buff *skb = rx->skb; 94 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 95 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 96 97 /* 98 * it makes no sense to check for MIC errors on anything other 99 * than data frames. 100 */ 101 if (!ieee80211_is_data_present(hdr->frame_control)) 102 return RX_CONTINUE; 103 104 /* 105 * No way to verify the MIC if the hardware stripped it or 106 * the IV with the key index. In this case we have solely rely 107 * on the driver to set RX_FLAG_MMIC_ERROR in the event of a 108 * MIC failure report. 109 */ 110 if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) { 111 if (status->flag & RX_FLAG_MMIC_ERROR) 112 goto mic_fail_no_key; 113 114 if (!(status->flag & RX_FLAG_IV_STRIPPED) && rx->key && 115 rx->key->conf.cipher == WLAN_CIPHER_SUITE_TKIP) 116 goto update_iv; 117 118 return RX_CONTINUE; 119 } 120 121 /* 122 * Some hardware seems to generate Michael MIC failure reports; even 123 * though, the frame was not encrypted with TKIP and therefore has no 124 * MIC. Ignore the flag them to avoid triggering countermeasures. 125 */ 126 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP || 127 !(status->flag & RX_FLAG_DECRYPTED)) 128 return RX_CONTINUE; 129 130 if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) { 131 /* 132 * APs with pairwise keys should never receive Michael MIC 133 * errors for non-zero keyidx because these are reserved for 134 * group keys and only the AP is sending real multicast 135 * frames in the BSS. 136 */ 137 return RX_DROP_UNUSABLE; 138 } 139 140 if (status->flag & RX_FLAG_MMIC_ERROR) 141 goto mic_fail; 142 143 hdrlen = ieee80211_hdrlen(hdr->frame_control); 144 if (skb->len < hdrlen + MICHAEL_MIC_LEN) 145 return RX_DROP_UNUSABLE; 146 147 if (skb_linearize(rx->skb)) 148 return RX_DROP_UNUSABLE; 149 hdr = (void *)skb->data; 150 151 data = skb->data + hdrlen; 152 data_len = skb->len - hdrlen - MICHAEL_MIC_LEN; 153 key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY]; 154 michael_mic(key, hdr, data, data_len, mic); 155 if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0) 156 goto mic_fail; 157 158 /* remove Michael MIC from payload */ 159 skb_trim(skb, skb->len - MICHAEL_MIC_LEN); 160 161 update_iv: 162 /* update IV in key information to be able to detect replays */ 163 rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip_iv32; 164 rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip_iv16; 165 166 return RX_CONTINUE; 167 168 mic_fail: 169 rx->key->u.tkip.mic_failures++; 170 171 mic_fail_no_key: 172 /* 173 * In some cases the key can be unset - e.g. a multicast packet, in 174 * a driver that supports HW encryption. Send up the key idx only if 175 * the key is set. 176 */ 177 cfg80211_michael_mic_failure(rx->sdata->dev, hdr->addr2, 178 is_multicast_ether_addr(hdr->addr1) ? 179 NL80211_KEYTYPE_GROUP : 180 NL80211_KEYTYPE_PAIRWISE, 181 rx->key ? rx->key->conf.keyidx : -1, 182 NULL, GFP_ATOMIC); 183 return RX_DROP_UNUSABLE; 184 } 185 186 187 static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) 188 { 189 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 190 struct ieee80211_key *key = tx->key; 191 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 192 unsigned int hdrlen; 193 int len, tail; 194 u8 *pos; 195 196 if (info->control.hw_key && 197 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) && 198 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) { 199 /* hwaccel - with no need for software-generated IV */ 200 return 0; 201 } 202 203 hdrlen = ieee80211_hdrlen(hdr->frame_control); 204 len = skb->len - hdrlen; 205 206 if (info->control.hw_key) 207 tail = 0; 208 else 209 tail = IEEE80211_TKIP_ICV_LEN; 210 211 if (WARN_ON(skb_tailroom(skb) < tail || 212 skb_headroom(skb) < IEEE80211_TKIP_IV_LEN)) 213 return -1; 214 215 pos = skb_push(skb, IEEE80211_TKIP_IV_LEN); 216 memmove(pos, pos + IEEE80211_TKIP_IV_LEN, hdrlen); 217 pos += hdrlen; 218 219 /* the HW only needs room for the IV, but not the actual IV */ 220 if (info->control.hw_key && 221 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) 222 return 0; 223 224 /* Increase IV for the frame */ 225 spin_lock(&key->u.tkip.txlock); 226 key->u.tkip.tx.iv16++; 227 if (key->u.tkip.tx.iv16 == 0) 228 key->u.tkip.tx.iv32++; 229 pos = ieee80211_tkip_add_iv(pos, key); 230 spin_unlock(&key->u.tkip.txlock); 231 232 /* hwaccel - with software IV */ 233 if (info->control.hw_key) 234 return 0; 235 236 /* Add room for ICV */ 237 skb_put(skb, IEEE80211_TKIP_ICV_LEN); 238 239 return ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm, 240 key, skb, pos, len); 241 } 242 243 244 ieee80211_tx_result 245 ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx) 246 { 247 struct sk_buff *skb; 248 249 ieee80211_tx_set_protected(tx); 250 251 skb_queue_walk(&tx->skbs, skb) { 252 if (tkip_encrypt_skb(tx, skb) < 0) 253 return TX_DROP; 254 } 255 256 return TX_CONTINUE; 257 } 258 259 260 ieee80211_rx_result 261 ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx) 262 { 263 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data; 264 int hdrlen, res, hwaccel = 0; 265 struct ieee80211_key *key = rx->key; 266 struct sk_buff *skb = rx->skb; 267 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 268 269 hdrlen = ieee80211_hdrlen(hdr->frame_control); 270 271 if (!ieee80211_is_data(hdr->frame_control)) 272 return RX_CONTINUE; 273 274 if (!rx->sta || skb->len - hdrlen < 12) 275 return RX_DROP_UNUSABLE; 276 277 /* it may be possible to optimize this a bit more */ 278 if (skb_linearize(rx->skb)) 279 return RX_DROP_UNUSABLE; 280 hdr = (void *)skb->data; 281 282 /* 283 * Let TKIP code verify IV, but skip decryption. 284 * In the case where hardware checks the IV as well, 285 * we don't even get here, see ieee80211_rx_h_decrypt() 286 */ 287 if (status->flag & RX_FLAG_DECRYPTED) 288 hwaccel = 1; 289 290 res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm, 291 key, skb->data + hdrlen, 292 skb->len - hdrlen, rx->sta->sta.addr, 293 hdr->addr1, hwaccel, rx->security_idx, 294 &rx->tkip_iv32, 295 &rx->tkip_iv16); 296 if (res != TKIP_DECRYPT_OK) 297 return RX_DROP_UNUSABLE; 298 299 /* Trim ICV */ 300 skb_trim(skb, skb->len - IEEE80211_TKIP_ICV_LEN); 301 302 /* Remove IV */ 303 memmove(skb->data + IEEE80211_TKIP_IV_LEN, skb->data, hdrlen); 304 skb_pull(skb, IEEE80211_TKIP_IV_LEN); 305 306 return RX_CONTINUE; 307 } 308 309 310 static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad) 311 { 312 __le16 mask_fc; 313 int a4_included, mgmt; 314 u8 qos_tid; 315 u16 len_a; 316 unsigned int hdrlen; 317 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 318 319 /* 320 * Mask FC: zero subtype b4 b5 b6 (if not mgmt) 321 * Retry, PwrMgt, MoreData; set Protected 322 */ 323 mgmt = ieee80211_is_mgmt(hdr->frame_control); 324 mask_fc = hdr->frame_control; 325 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | 326 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA); 327 if (!mgmt) 328 mask_fc &= ~cpu_to_le16(0x0070); 329 mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); 330 331 hdrlen = ieee80211_hdrlen(hdr->frame_control); 332 len_a = hdrlen - 2; 333 a4_included = ieee80211_has_a4(hdr->frame_control); 334 335 if (ieee80211_is_data_qos(hdr->frame_control)) 336 qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; 337 else 338 qos_tid = 0; 339 340 /* In CCM, the initial vectors (IV) used for CTR mode encryption and CBC 341 * mode authentication are not allowed to collide, yet both are derived 342 * from this vector b_0. We only set L := 1 here to indicate that the 343 * data size can be represented in (L+1) bytes. The CCM layer will take 344 * care of storing the data length in the top (L+1) bytes and setting 345 * and clearing the other bits as is required to derive the two IVs. 346 */ 347 b_0[0] = 0x1; 348 349 /* Nonce: Nonce Flags | A2 | PN 350 * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7) 351 */ 352 b_0[1] = qos_tid | (mgmt << 4); 353 memcpy(&b_0[2], hdr->addr2, ETH_ALEN); 354 memcpy(&b_0[8], pn, IEEE80211_CCMP_PN_LEN); 355 356 /* AAD (extra authenticate-only data) / masked 802.11 header 357 * FC | A1 | A2 | A3 | SC | [A4] | [QC] */ 358 put_unaligned_be16(len_a, &aad[0]); 359 put_unaligned(mask_fc, (__le16 *)&aad[2]); 360 memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN); 361 362 /* Mask Seq#, leave Frag# */ 363 aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f; 364 aad[23] = 0; 365 366 if (a4_included) { 367 memcpy(&aad[24], hdr->addr4, ETH_ALEN); 368 aad[30] = qos_tid; 369 aad[31] = 0; 370 } else { 371 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN); 372 aad[24] = qos_tid; 373 } 374 } 375 376 377 static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id) 378 { 379 hdr[0] = pn[5]; 380 hdr[1] = pn[4]; 381 hdr[2] = 0; 382 hdr[3] = 0x20 | (key_id << 6); 383 hdr[4] = pn[3]; 384 hdr[5] = pn[2]; 385 hdr[6] = pn[1]; 386 hdr[7] = pn[0]; 387 } 388 389 390 static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr) 391 { 392 pn[0] = hdr[7]; 393 pn[1] = hdr[6]; 394 pn[2] = hdr[5]; 395 pn[3] = hdr[4]; 396 pn[4] = hdr[1]; 397 pn[5] = hdr[0]; 398 } 399 400 401 static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb, 402 unsigned int mic_len) 403 { 404 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 405 struct ieee80211_key *key = tx->key; 406 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 407 int hdrlen, len, tail; 408 u8 *pos; 409 u8 pn[6]; 410 u64 pn64; 411 u8 aad[2 * AES_BLOCK_SIZE]; 412 u8 b_0[AES_BLOCK_SIZE]; 413 414 if (info->control.hw_key && 415 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) && 416 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) && 417 !((info->control.hw_key->flags & 418 IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) && 419 ieee80211_is_mgmt(hdr->frame_control))) { 420 /* 421 * hwaccel has no need for preallocated room for CCMP 422 * header or MIC fields 423 */ 424 return 0; 425 } 426 427 hdrlen = ieee80211_hdrlen(hdr->frame_control); 428 len = skb->len - hdrlen; 429 430 if (info->control.hw_key) 431 tail = 0; 432 else 433 tail = mic_len; 434 435 if (WARN_ON(skb_tailroom(skb) < tail || 436 skb_headroom(skb) < IEEE80211_CCMP_HDR_LEN)) 437 return -1; 438 439 pos = skb_push(skb, IEEE80211_CCMP_HDR_LEN); 440 memmove(pos, pos + IEEE80211_CCMP_HDR_LEN, hdrlen); 441 442 /* the HW only needs room for the IV, but not the actual IV */ 443 if (info->control.hw_key && 444 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) 445 return 0; 446 447 hdr = (struct ieee80211_hdr *) pos; 448 pos += hdrlen; 449 450 pn64 = atomic64_inc_return(&key->conf.tx_pn); 451 452 pn[5] = pn64; 453 pn[4] = pn64 >> 8; 454 pn[3] = pn64 >> 16; 455 pn[2] = pn64 >> 24; 456 pn[1] = pn64 >> 32; 457 pn[0] = pn64 >> 40; 458 459 ccmp_pn2hdr(pos, pn, key->conf.keyidx); 460 461 /* hwaccel - with software CCMP header */ 462 if (info->control.hw_key) 463 return 0; 464 465 pos += IEEE80211_CCMP_HDR_LEN; 466 ccmp_special_blocks(skb, pn, b_0, aad); 467 ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, b_0, aad, pos, len, 468 skb_put(skb, mic_len), mic_len); 469 470 return 0; 471 } 472 473 474 ieee80211_tx_result 475 ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx, 476 unsigned int mic_len) 477 { 478 struct sk_buff *skb; 479 480 ieee80211_tx_set_protected(tx); 481 482 skb_queue_walk(&tx->skbs, skb) { 483 if (ccmp_encrypt_skb(tx, skb, mic_len) < 0) 484 return TX_DROP; 485 } 486 487 return TX_CONTINUE; 488 } 489 490 491 ieee80211_rx_result 492 ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx, 493 unsigned int mic_len) 494 { 495 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 496 int hdrlen; 497 struct ieee80211_key *key = rx->key; 498 struct sk_buff *skb = rx->skb; 499 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 500 u8 pn[IEEE80211_CCMP_PN_LEN]; 501 int data_len; 502 int queue; 503 504 hdrlen = ieee80211_hdrlen(hdr->frame_control); 505 506 if (!ieee80211_is_data(hdr->frame_control) && 507 !ieee80211_is_robust_mgmt_frame(skb)) 508 return RX_CONTINUE; 509 510 data_len = skb->len - hdrlen - IEEE80211_CCMP_HDR_LEN - mic_len; 511 if (!rx->sta || data_len < 0) 512 return RX_DROP_UNUSABLE; 513 514 if (status->flag & RX_FLAG_DECRYPTED) { 515 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_CCMP_HDR_LEN)) 516 return RX_DROP_UNUSABLE; 517 } else { 518 if (skb_linearize(rx->skb)) 519 return RX_DROP_UNUSABLE; 520 } 521 522 if (!(status->flag & RX_FLAG_PN_VALIDATED)) { 523 ccmp_hdr2pn(pn, skb->data + hdrlen); 524 525 queue = rx->security_idx; 526 527 if (memcmp(pn, key->u.ccmp.rx_pn[queue], 528 IEEE80211_CCMP_PN_LEN) <= 0) { 529 key->u.ccmp.replays++; 530 return RX_DROP_UNUSABLE; 531 } 532 533 if (!(status->flag & RX_FLAG_DECRYPTED)) { 534 u8 aad[2 * AES_BLOCK_SIZE]; 535 u8 b_0[AES_BLOCK_SIZE]; 536 /* hardware didn't decrypt/verify MIC */ 537 ccmp_special_blocks(skb, pn, b_0, aad); 538 539 if (ieee80211_aes_ccm_decrypt( 540 key->u.ccmp.tfm, b_0, aad, 541 skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN, 542 data_len, 543 skb->data + skb->len - mic_len, mic_len)) 544 return RX_DROP_UNUSABLE; 545 } 546 547 memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN); 548 } 549 550 /* Remove CCMP header and MIC */ 551 if (pskb_trim(skb, skb->len - mic_len)) 552 return RX_DROP_UNUSABLE; 553 memmove(skb->data + IEEE80211_CCMP_HDR_LEN, skb->data, hdrlen); 554 skb_pull(skb, IEEE80211_CCMP_HDR_LEN); 555 556 return RX_CONTINUE; 557 } 558 559 static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad) 560 { 561 __le16 mask_fc; 562 u8 qos_tid; 563 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 564 565 memcpy(j_0, hdr->addr2, ETH_ALEN); 566 memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN); 567 j_0[13] = 0; 568 j_0[14] = 0; 569 j_0[AES_BLOCK_SIZE - 1] = 0x01; 570 571 /* AAD (extra authenticate-only data) / masked 802.11 header 572 * FC | A1 | A2 | A3 | SC | [A4] | [QC] 573 */ 574 put_unaligned_be16(ieee80211_hdrlen(hdr->frame_control) - 2, &aad[0]); 575 /* Mask FC: zero subtype b4 b5 b6 (if not mgmt) 576 * Retry, PwrMgt, MoreData; set Protected 577 */ 578 mask_fc = hdr->frame_control; 579 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | 580 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA); 581 if (!ieee80211_is_mgmt(hdr->frame_control)) 582 mask_fc &= ~cpu_to_le16(0x0070); 583 mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); 584 585 put_unaligned(mask_fc, (__le16 *)&aad[2]); 586 memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN); 587 588 /* Mask Seq#, leave Frag# */ 589 aad[22] = *((u8 *)&hdr->seq_ctrl) & 0x0f; 590 aad[23] = 0; 591 592 if (ieee80211_is_data_qos(hdr->frame_control)) 593 qos_tid = *ieee80211_get_qos_ctl(hdr) & 594 IEEE80211_QOS_CTL_TID_MASK; 595 else 596 qos_tid = 0; 597 598 if (ieee80211_has_a4(hdr->frame_control)) { 599 memcpy(&aad[24], hdr->addr4, ETH_ALEN); 600 aad[30] = qos_tid; 601 aad[31] = 0; 602 } else { 603 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN); 604 aad[24] = qos_tid; 605 } 606 } 607 608 static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id) 609 { 610 hdr[0] = pn[5]; 611 hdr[1] = pn[4]; 612 hdr[2] = 0; 613 hdr[3] = 0x20 | (key_id << 6); 614 hdr[4] = pn[3]; 615 hdr[5] = pn[2]; 616 hdr[6] = pn[1]; 617 hdr[7] = pn[0]; 618 } 619 620 static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr) 621 { 622 pn[0] = hdr[7]; 623 pn[1] = hdr[6]; 624 pn[2] = hdr[5]; 625 pn[3] = hdr[4]; 626 pn[4] = hdr[1]; 627 pn[5] = hdr[0]; 628 } 629 630 static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) 631 { 632 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 633 struct ieee80211_key *key = tx->key; 634 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 635 int hdrlen, len, tail; 636 u8 *pos; 637 u8 pn[6]; 638 u64 pn64; 639 u8 aad[2 * AES_BLOCK_SIZE]; 640 u8 j_0[AES_BLOCK_SIZE]; 641 642 if (info->control.hw_key && 643 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) && 644 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) && 645 !((info->control.hw_key->flags & 646 IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) && 647 ieee80211_is_mgmt(hdr->frame_control))) { 648 /* hwaccel has no need for preallocated room for GCMP 649 * header or MIC fields 650 */ 651 return 0; 652 } 653 654 hdrlen = ieee80211_hdrlen(hdr->frame_control); 655 len = skb->len - hdrlen; 656 657 if (info->control.hw_key) 658 tail = 0; 659 else 660 tail = IEEE80211_GCMP_MIC_LEN; 661 662 if (WARN_ON(skb_tailroom(skb) < tail || 663 skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN)) 664 return -1; 665 666 pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN); 667 memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen); 668 skb_set_network_header(skb, skb_network_offset(skb) + 669 IEEE80211_GCMP_HDR_LEN); 670 671 /* the HW only needs room for the IV, but not the actual IV */ 672 if (info->control.hw_key && 673 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) 674 return 0; 675 676 hdr = (struct ieee80211_hdr *)pos; 677 pos += hdrlen; 678 679 pn64 = atomic64_inc_return(&key->conf.tx_pn); 680 681 pn[5] = pn64; 682 pn[4] = pn64 >> 8; 683 pn[3] = pn64 >> 16; 684 pn[2] = pn64 >> 24; 685 pn[1] = pn64 >> 32; 686 pn[0] = pn64 >> 40; 687 688 gcmp_pn2hdr(pos, pn, key->conf.keyidx); 689 690 /* hwaccel - with software GCMP header */ 691 if (info->control.hw_key) 692 return 0; 693 694 pos += IEEE80211_GCMP_HDR_LEN; 695 gcmp_special_blocks(skb, pn, j_0, aad); 696 ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len, 697 skb_put(skb, IEEE80211_GCMP_MIC_LEN)); 698 699 return 0; 700 } 701 702 ieee80211_tx_result 703 ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx) 704 { 705 struct sk_buff *skb; 706 707 ieee80211_tx_set_protected(tx); 708 709 skb_queue_walk(&tx->skbs, skb) { 710 if (gcmp_encrypt_skb(tx, skb) < 0) 711 return TX_DROP; 712 } 713 714 return TX_CONTINUE; 715 } 716 717 ieee80211_rx_result 718 ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx) 719 { 720 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 721 int hdrlen; 722 struct ieee80211_key *key = rx->key; 723 struct sk_buff *skb = rx->skb; 724 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 725 u8 pn[IEEE80211_GCMP_PN_LEN]; 726 int data_len; 727 int queue; 728 729 hdrlen = ieee80211_hdrlen(hdr->frame_control); 730 731 if (!ieee80211_is_data(hdr->frame_control) && 732 !ieee80211_is_robust_mgmt_frame(skb)) 733 return RX_CONTINUE; 734 735 data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN - 736 IEEE80211_GCMP_MIC_LEN; 737 if (!rx->sta || data_len < 0) 738 return RX_DROP_UNUSABLE; 739 740 if (status->flag & RX_FLAG_DECRYPTED) { 741 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN)) 742 return RX_DROP_UNUSABLE; 743 } else { 744 if (skb_linearize(rx->skb)) 745 return RX_DROP_UNUSABLE; 746 } 747 748 if (!(status->flag & RX_FLAG_PN_VALIDATED)) { 749 gcmp_hdr2pn(pn, skb->data + hdrlen); 750 751 queue = rx->security_idx; 752 753 if (memcmp(pn, key->u.gcmp.rx_pn[queue], 754 IEEE80211_GCMP_PN_LEN) <= 0) { 755 key->u.gcmp.replays++; 756 return RX_DROP_UNUSABLE; 757 } 758 759 if (!(status->flag & RX_FLAG_DECRYPTED)) { 760 u8 aad[2 * AES_BLOCK_SIZE]; 761 u8 j_0[AES_BLOCK_SIZE]; 762 /* hardware didn't decrypt/verify MIC */ 763 gcmp_special_blocks(skb, pn, j_0, aad); 764 765 if (ieee80211_aes_gcm_decrypt( 766 key->u.gcmp.tfm, j_0, aad, 767 skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN, 768 data_len, 769 skb->data + skb->len - 770 IEEE80211_GCMP_MIC_LEN)) 771 return RX_DROP_UNUSABLE; 772 } 773 774 memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN); 775 } 776 777 /* Remove GCMP header and MIC */ 778 if (pskb_trim(skb, skb->len - IEEE80211_GCMP_MIC_LEN)) 779 return RX_DROP_UNUSABLE; 780 memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen); 781 skb_pull(skb, IEEE80211_GCMP_HDR_LEN); 782 783 return RX_CONTINUE; 784 } 785 786 static ieee80211_tx_result 787 ieee80211_crypto_cs_encrypt(struct ieee80211_tx_data *tx, 788 struct sk_buff *skb) 789 { 790 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 791 struct ieee80211_key *key = tx->key; 792 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 793 int hdrlen; 794 u8 *pos, iv_len = key->conf.iv_len; 795 796 if (info->control.hw_key && 797 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) { 798 /* hwaccel has no need for preallocated head room */ 799 return TX_CONTINUE; 800 } 801 802 if (unlikely(skb_headroom(skb) < iv_len && 803 pskb_expand_head(skb, iv_len, 0, GFP_ATOMIC))) 804 return TX_DROP; 805 806 hdrlen = ieee80211_hdrlen(hdr->frame_control); 807 808 pos = skb_push(skb, iv_len); 809 memmove(pos, pos + iv_len, hdrlen); 810 811 return TX_CONTINUE; 812 } 813 814 static inline int ieee80211_crypto_cs_pn_compare(u8 *pn1, u8 *pn2, int len) 815 { 816 int i; 817 818 /* pn is little endian */ 819 for (i = len - 1; i >= 0; i--) { 820 if (pn1[i] < pn2[i]) 821 return -1; 822 else if (pn1[i] > pn2[i]) 823 return 1; 824 } 825 826 return 0; 827 } 828 829 static ieee80211_rx_result 830 ieee80211_crypto_cs_decrypt(struct ieee80211_rx_data *rx) 831 { 832 struct ieee80211_key *key = rx->key; 833 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 834 const struct ieee80211_cipher_scheme *cs = NULL; 835 int hdrlen = ieee80211_hdrlen(hdr->frame_control); 836 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 837 int data_len; 838 u8 *rx_pn; 839 u8 *skb_pn; 840 u8 qos_tid; 841 842 if (!rx->sta || !rx->sta->cipher_scheme || 843 !(status->flag & RX_FLAG_DECRYPTED)) 844 return RX_DROP_UNUSABLE; 845 846 if (!ieee80211_is_data(hdr->frame_control)) 847 return RX_CONTINUE; 848 849 cs = rx->sta->cipher_scheme; 850 851 data_len = rx->skb->len - hdrlen - cs->hdr_len; 852 853 if (data_len < 0) 854 return RX_DROP_UNUSABLE; 855 856 if (ieee80211_is_data_qos(hdr->frame_control)) 857 qos_tid = *ieee80211_get_qos_ctl(hdr) & 858 IEEE80211_QOS_CTL_TID_MASK; 859 else 860 qos_tid = 0; 861 862 if (skb_linearize(rx->skb)) 863 return RX_DROP_UNUSABLE; 864 865 hdr = (struct ieee80211_hdr *)rx->skb->data; 866 867 rx_pn = key->u.gen.rx_pn[qos_tid]; 868 skb_pn = rx->skb->data + hdrlen + cs->pn_off; 869 870 if (ieee80211_crypto_cs_pn_compare(skb_pn, rx_pn, cs->pn_len) <= 0) 871 return RX_DROP_UNUSABLE; 872 873 memcpy(rx_pn, skb_pn, cs->pn_len); 874 875 /* remove security header and MIC */ 876 if (pskb_trim(rx->skb, rx->skb->len - cs->mic_len)) 877 return RX_DROP_UNUSABLE; 878 879 memmove(rx->skb->data + cs->hdr_len, rx->skb->data, hdrlen); 880 skb_pull(rx->skb, cs->hdr_len); 881 882 return RX_CONTINUE; 883 } 884 885 static void bip_aad(struct sk_buff *skb, u8 *aad) 886 { 887 __le16 mask_fc; 888 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 889 890 /* BIP AAD: FC(masked) || A1 || A2 || A3 */ 891 892 /* FC type/subtype */ 893 /* Mask FC Retry, PwrMgt, MoreData flags to zero */ 894 mask_fc = hdr->frame_control; 895 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM | 896 IEEE80211_FCTL_MOREDATA); 897 put_unaligned(mask_fc, (__le16 *) &aad[0]); 898 /* A1 || A2 || A3 */ 899 memcpy(aad + 2, &hdr->addr1, 3 * ETH_ALEN); 900 } 901 902 903 static inline void bip_ipn_set64(u8 *d, u64 pn) 904 { 905 *d++ = pn; 906 *d++ = pn >> 8; 907 *d++ = pn >> 16; 908 *d++ = pn >> 24; 909 *d++ = pn >> 32; 910 *d = pn >> 40; 911 } 912 913 static inline void bip_ipn_swap(u8 *d, const u8 *s) 914 { 915 *d++ = s[5]; 916 *d++ = s[4]; 917 *d++ = s[3]; 918 *d++ = s[2]; 919 *d++ = s[1]; 920 *d = s[0]; 921 } 922 923 924 ieee80211_tx_result 925 ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx) 926 { 927 struct sk_buff *skb; 928 struct ieee80211_tx_info *info; 929 struct ieee80211_key *key = tx->key; 930 struct ieee80211_mmie *mmie; 931 u8 aad[20]; 932 u64 pn64; 933 934 if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) 935 return TX_DROP; 936 937 skb = skb_peek(&tx->skbs); 938 939 info = IEEE80211_SKB_CB(skb); 940 941 if (info->control.hw_key) 942 return TX_CONTINUE; 943 944 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) 945 return TX_DROP; 946 947 mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie)); 948 mmie->element_id = WLAN_EID_MMIE; 949 mmie->length = sizeof(*mmie) - 2; 950 mmie->key_id = cpu_to_le16(key->conf.keyidx); 951 952 /* PN = PN + 1 */ 953 pn64 = atomic64_inc_return(&key->conf.tx_pn); 954 955 bip_ipn_set64(mmie->sequence_number, pn64); 956 957 bip_aad(skb, aad); 958 959 /* 960 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64) 961 */ 962 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad, 963 skb->data + 24, skb->len - 24, mmie->mic); 964 965 return TX_CONTINUE; 966 } 967 968 ieee80211_tx_result 969 ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx) 970 { 971 struct sk_buff *skb; 972 struct ieee80211_tx_info *info; 973 struct ieee80211_key *key = tx->key; 974 struct ieee80211_mmie_16 *mmie; 975 u8 aad[20]; 976 u64 pn64; 977 978 if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) 979 return TX_DROP; 980 981 skb = skb_peek(&tx->skbs); 982 983 info = IEEE80211_SKB_CB(skb); 984 985 if (info->control.hw_key) 986 return TX_CONTINUE; 987 988 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) 989 return TX_DROP; 990 991 mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie)); 992 mmie->element_id = WLAN_EID_MMIE; 993 mmie->length = sizeof(*mmie) - 2; 994 mmie->key_id = cpu_to_le16(key->conf.keyidx); 995 996 /* PN = PN + 1 */ 997 pn64 = atomic64_inc_return(&key->conf.tx_pn); 998 999 bip_ipn_set64(mmie->sequence_number, pn64); 1000 1001 bip_aad(skb, aad); 1002 1003 /* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128) 1004 */ 1005 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad, 1006 skb->data + 24, skb->len - 24, mmie->mic); 1007 1008 return TX_CONTINUE; 1009 } 1010 1011 ieee80211_rx_result 1012 ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx) 1013 { 1014 struct sk_buff *skb = rx->skb; 1015 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1016 struct ieee80211_key *key = rx->key; 1017 struct ieee80211_mmie *mmie; 1018 u8 aad[20], mic[8], ipn[6]; 1019 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1020 1021 if (!ieee80211_is_mgmt(hdr->frame_control)) 1022 return RX_CONTINUE; 1023 1024 /* management frames are already linear */ 1025 1026 if (skb->len < 24 + sizeof(*mmie)) 1027 return RX_DROP_UNUSABLE; 1028 1029 mmie = (struct ieee80211_mmie *) 1030 (skb->data + skb->len - sizeof(*mmie)); 1031 if (mmie->element_id != WLAN_EID_MMIE || 1032 mmie->length != sizeof(*mmie) - 2) 1033 return RX_DROP_UNUSABLE; /* Invalid MMIE */ 1034 1035 bip_ipn_swap(ipn, mmie->sequence_number); 1036 1037 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) { 1038 key->u.aes_cmac.replays++; 1039 return RX_DROP_UNUSABLE; 1040 } 1041 1042 if (!(status->flag & RX_FLAG_DECRYPTED)) { 1043 /* hardware didn't decrypt/verify MIC */ 1044 bip_aad(skb, aad); 1045 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad, 1046 skb->data + 24, skb->len - 24, mic); 1047 if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) { 1048 key->u.aes_cmac.icverrors++; 1049 return RX_DROP_UNUSABLE; 1050 } 1051 } 1052 1053 memcpy(key->u.aes_cmac.rx_pn, ipn, 6); 1054 1055 /* Remove MMIE */ 1056 skb_trim(skb, skb->len - sizeof(*mmie)); 1057 1058 return RX_CONTINUE; 1059 } 1060 1061 ieee80211_rx_result 1062 ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx) 1063 { 1064 struct sk_buff *skb = rx->skb; 1065 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1066 struct ieee80211_key *key = rx->key; 1067 struct ieee80211_mmie_16 *mmie; 1068 u8 aad[20], mic[16], ipn[6]; 1069 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1070 1071 if (!ieee80211_is_mgmt(hdr->frame_control)) 1072 return RX_CONTINUE; 1073 1074 /* management frames are already linear */ 1075 1076 if (skb->len < 24 + sizeof(*mmie)) 1077 return RX_DROP_UNUSABLE; 1078 1079 mmie = (struct ieee80211_mmie_16 *) 1080 (skb->data + skb->len - sizeof(*mmie)); 1081 if (mmie->element_id != WLAN_EID_MMIE || 1082 mmie->length != sizeof(*mmie) - 2) 1083 return RX_DROP_UNUSABLE; /* Invalid MMIE */ 1084 1085 bip_ipn_swap(ipn, mmie->sequence_number); 1086 1087 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) { 1088 key->u.aes_cmac.replays++; 1089 return RX_DROP_UNUSABLE; 1090 } 1091 1092 if (!(status->flag & RX_FLAG_DECRYPTED)) { 1093 /* hardware didn't decrypt/verify MIC */ 1094 bip_aad(skb, aad); 1095 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad, 1096 skb->data + 24, skb->len - 24, mic); 1097 if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) { 1098 key->u.aes_cmac.icverrors++; 1099 return RX_DROP_UNUSABLE; 1100 } 1101 } 1102 1103 memcpy(key->u.aes_cmac.rx_pn, ipn, 6); 1104 1105 /* Remove MMIE */ 1106 skb_trim(skb, skb->len - sizeof(*mmie)); 1107 1108 return RX_CONTINUE; 1109 } 1110 1111 ieee80211_tx_result 1112 ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx) 1113 { 1114 struct sk_buff *skb; 1115 struct ieee80211_tx_info *info; 1116 struct ieee80211_key *key = tx->key; 1117 struct ieee80211_mmie_16 *mmie; 1118 struct ieee80211_hdr *hdr; 1119 u8 aad[20]; 1120 u64 pn64; 1121 u8 nonce[12]; 1122 1123 if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) 1124 return TX_DROP; 1125 1126 skb = skb_peek(&tx->skbs); 1127 1128 info = IEEE80211_SKB_CB(skb); 1129 1130 if (info->control.hw_key) 1131 return TX_CONTINUE; 1132 1133 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) 1134 return TX_DROP; 1135 1136 mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie)); 1137 mmie->element_id = WLAN_EID_MMIE; 1138 mmie->length = sizeof(*mmie) - 2; 1139 mmie->key_id = cpu_to_le16(key->conf.keyidx); 1140 1141 /* PN = PN + 1 */ 1142 pn64 = atomic64_inc_return(&key->conf.tx_pn); 1143 1144 bip_ipn_set64(mmie->sequence_number, pn64); 1145 1146 bip_aad(skb, aad); 1147 1148 hdr = (struct ieee80211_hdr *)skb->data; 1149 memcpy(nonce, hdr->addr2, ETH_ALEN); 1150 bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number); 1151 1152 /* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */ 1153 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce, 1154 skb->data + 24, skb->len - 24, mmie->mic) < 0) 1155 return TX_DROP; 1156 1157 return TX_CONTINUE; 1158 } 1159 1160 ieee80211_rx_result 1161 ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx) 1162 { 1163 struct sk_buff *skb = rx->skb; 1164 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1165 struct ieee80211_key *key = rx->key; 1166 struct ieee80211_mmie_16 *mmie; 1167 u8 aad[20], mic[16], ipn[6], nonce[12]; 1168 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1169 1170 if (!ieee80211_is_mgmt(hdr->frame_control)) 1171 return RX_CONTINUE; 1172 1173 /* management frames are already linear */ 1174 1175 if (skb->len < 24 + sizeof(*mmie)) 1176 return RX_DROP_UNUSABLE; 1177 1178 mmie = (struct ieee80211_mmie_16 *) 1179 (skb->data + skb->len - sizeof(*mmie)); 1180 if (mmie->element_id != WLAN_EID_MMIE || 1181 mmie->length != sizeof(*mmie) - 2) 1182 return RX_DROP_UNUSABLE; /* Invalid MMIE */ 1183 1184 bip_ipn_swap(ipn, mmie->sequence_number); 1185 1186 if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) { 1187 key->u.aes_gmac.replays++; 1188 return RX_DROP_UNUSABLE; 1189 } 1190 1191 if (!(status->flag & RX_FLAG_DECRYPTED)) { 1192 /* hardware didn't decrypt/verify MIC */ 1193 bip_aad(skb, aad); 1194 1195 memcpy(nonce, hdr->addr2, ETH_ALEN); 1196 memcpy(nonce + ETH_ALEN, ipn, 6); 1197 1198 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce, 1199 skb->data + 24, skb->len - 24, 1200 mic) < 0 || 1201 memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) { 1202 key->u.aes_gmac.icverrors++; 1203 return RX_DROP_UNUSABLE; 1204 } 1205 } 1206 1207 memcpy(key->u.aes_gmac.rx_pn, ipn, 6); 1208 1209 /* Remove MMIE */ 1210 skb_trim(skb, skb->len - sizeof(*mmie)); 1211 1212 return RX_CONTINUE; 1213 } 1214 1215 ieee80211_tx_result 1216 ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx) 1217 { 1218 struct sk_buff *skb; 1219 struct ieee80211_tx_info *info = NULL; 1220 ieee80211_tx_result res; 1221 1222 skb_queue_walk(&tx->skbs, skb) { 1223 info = IEEE80211_SKB_CB(skb); 1224 1225 /* handle hw-only algorithm */ 1226 if (!info->control.hw_key) 1227 return TX_DROP; 1228 1229 if (tx->key->flags & KEY_FLAG_CIPHER_SCHEME) { 1230 res = ieee80211_crypto_cs_encrypt(tx, skb); 1231 if (res != TX_CONTINUE) 1232 return res; 1233 } 1234 } 1235 1236 ieee80211_tx_set_protected(tx); 1237 1238 return TX_CONTINUE; 1239 } 1240 1241 ieee80211_rx_result 1242 ieee80211_crypto_hw_decrypt(struct ieee80211_rx_data *rx) 1243 { 1244 if (rx->sta && rx->sta->cipher_scheme) 1245 return ieee80211_crypto_cs_decrypt(rx); 1246 1247 return RX_DROP_UNUSABLE; 1248 } 1249