1 /* 2 * Copyright 2002-2004, Instant802 Networks, Inc. 3 * Copyright 2008, Jouni Malinen <j@w1.fi> 4 * Copyright (C) 2016-2017 Intel Deutschland GmbH 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 */ 10 11 #include <linux/netdevice.h> 12 #include <linux/types.h> 13 #include <linux/skbuff.h> 14 #include <linux/compiler.h> 15 #include <linux/ieee80211.h> 16 #include <linux/gfp.h> 17 #include <asm/unaligned.h> 18 #include <net/mac80211.h> 19 #include <crypto/aes.h> 20 #include <crypto/algapi.h> 21 22 #include "ieee80211_i.h" 23 #include "michael.h" 24 #include "tkip.h" 25 #include "aes_ccm.h" 26 #include "aes_cmac.h" 27 #include "aes_gmac.h" 28 #include "aes_gcm.h" 29 #include "wpa.h" 30 31 ieee80211_tx_result 32 ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx) 33 { 34 u8 *data, *key, *mic; 35 size_t data_len; 36 unsigned int hdrlen; 37 struct ieee80211_hdr *hdr; 38 struct sk_buff *skb = tx->skb; 39 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 40 int tail; 41 42 hdr = (struct ieee80211_hdr *)skb->data; 43 if (!tx->key || tx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP || 44 skb->len < 24 || !ieee80211_is_data_present(hdr->frame_control)) 45 return TX_CONTINUE; 46 47 hdrlen = ieee80211_hdrlen(hdr->frame_control); 48 if (skb->len < hdrlen) 49 return TX_DROP; 50 51 data = skb->data + hdrlen; 52 data_len = skb->len - hdrlen; 53 54 if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) { 55 /* Need to use software crypto for the test */ 56 info->control.hw_key = NULL; 57 } 58 59 if (info->control.hw_key && 60 (info->flags & IEEE80211_TX_CTL_DONTFRAG || 61 ieee80211_hw_check(&tx->local->hw, SUPPORTS_TX_FRAG)) && 62 !(tx->key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC | 63 IEEE80211_KEY_FLAG_PUT_MIC_SPACE))) { 64 /* hwaccel - with no need for SW-generated MMIC or MIC space */ 65 return TX_CONTINUE; 66 } 67 68 tail = MICHAEL_MIC_LEN; 69 if (!info->control.hw_key) 70 tail += IEEE80211_TKIP_ICV_LEN; 71 72 if (WARN(skb_tailroom(skb) < tail || 73 skb_headroom(skb) < IEEE80211_TKIP_IV_LEN, 74 "mmic: not enough head/tail (%d/%d,%d/%d)\n", 75 skb_headroom(skb), IEEE80211_TKIP_IV_LEN, 76 skb_tailroom(skb), tail)) 77 return TX_DROP; 78 79 mic = skb_put(skb, MICHAEL_MIC_LEN); 80 81 if (tx->key->conf.flags & IEEE80211_KEY_FLAG_PUT_MIC_SPACE) { 82 /* Zeroed MIC can help with debug */ 83 memset(mic, 0, MICHAEL_MIC_LEN); 84 return TX_CONTINUE; 85 } 86 87 key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY]; 88 michael_mic(key, hdr, data, data_len, mic); 89 if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) 90 mic[0]++; 91 92 return TX_CONTINUE; 93 } 94 95 96 ieee80211_rx_result 97 ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx) 98 { 99 u8 *data, *key = NULL; 100 size_t data_len; 101 unsigned int hdrlen; 102 u8 mic[MICHAEL_MIC_LEN]; 103 struct sk_buff *skb = rx->skb; 104 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 105 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 106 107 /* 108 * it makes no sense to check for MIC errors on anything other 109 * than data frames. 110 */ 111 if (!ieee80211_is_data_present(hdr->frame_control)) 112 return RX_CONTINUE; 113 114 /* 115 * No way to verify the MIC if the hardware stripped it or 116 * the IV with the key index. In this case we have solely rely 117 * on the driver to set RX_FLAG_MMIC_ERROR in the event of a 118 * MIC failure report. 119 */ 120 if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) { 121 if (status->flag & RX_FLAG_MMIC_ERROR) 122 goto mic_fail_no_key; 123 124 if (!(status->flag & RX_FLAG_IV_STRIPPED) && rx->key && 125 rx->key->conf.cipher == WLAN_CIPHER_SUITE_TKIP) 126 goto update_iv; 127 128 return RX_CONTINUE; 129 } 130 131 /* 132 * Some hardware seems to generate Michael MIC failure reports; even 133 * though, the frame was not encrypted with TKIP and therefore has no 134 * MIC. Ignore the flag them to avoid triggering countermeasures. 135 */ 136 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP || 137 !(status->flag & RX_FLAG_DECRYPTED)) 138 return RX_CONTINUE; 139 140 if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) { 141 /* 142 * APs with pairwise keys should never receive Michael MIC 143 * errors for non-zero keyidx because these are reserved for 144 * group keys and only the AP is sending real multicast 145 * frames in the BSS. 146 */ 147 return RX_DROP_UNUSABLE; 148 } 149 150 if (status->flag & RX_FLAG_MMIC_ERROR) 151 goto mic_fail; 152 153 hdrlen = ieee80211_hdrlen(hdr->frame_control); 154 if (skb->len < hdrlen + MICHAEL_MIC_LEN) 155 return RX_DROP_UNUSABLE; 156 157 if (skb_linearize(rx->skb)) 158 return RX_DROP_UNUSABLE; 159 hdr = (void *)skb->data; 160 161 data = skb->data + hdrlen; 162 data_len = skb->len - hdrlen - MICHAEL_MIC_LEN; 163 key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY]; 164 michael_mic(key, hdr, data, data_len, mic); 165 if (crypto_memneq(mic, data + data_len, MICHAEL_MIC_LEN)) 166 goto mic_fail; 167 168 /* remove Michael MIC from payload */ 169 skb_trim(skb, skb->len - MICHAEL_MIC_LEN); 170 171 update_iv: 172 /* update IV in key information to be able to detect replays */ 173 rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip_iv32; 174 rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip_iv16; 175 176 return RX_CONTINUE; 177 178 mic_fail: 179 rx->key->u.tkip.mic_failures++; 180 181 mic_fail_no_key: 182 /* 183 * In some cases the key can be unset - e.g. a multicast packet, in 184 * a driver that supports HW encryption. Send up the key idx only if 185 * the key is set. 186 */ 187 cfg80211_michael_mic_failure(rx->sdata->dev, hdr->addr2, 188 is_multicast_ether_addr(hdr->addr1) ? 189 NL80211_KEYTYPE_GROUP : 190 NL80211_KEYTYPE_PAIRWISE, 191 rx->key ? rx->key->conf.keyidx : -1, 192 NULL, GFP_ATOMIC); 193 return RX_DROP_UNUSABLE; 194 } 195 196 static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) 197 { 198 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 199 struct ieee80211_key *key = tx->key; 200 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 201 unsigned int hdrlen; 202 int len, tail; 203 u64 pn; 204 u8 *pos; 205 206 if (info->control.hw_key && 207 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) && 208 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) { 209 /* hwaccel - with no need for software-generated IV */ 210 return 0; 211 } 212 213 hdrlen = ieee80211_hdrlen(hdr->frame_control); 214 len = skb->len - hdrlen; 215 216 if (info->control.hw_key) 217 tail = 0; 218 else 219 tail = IEEE80211_TKIP_ICV_LEN; 220 221 if (WARN_ON(skb_tailroom(skb) < tail || 222 skb_headroom(skb) < IEEE80211_TKIP_IV_LEN)) 223 return -1; 224 225 pos = skb_push(skb, IEEE80211_TKIP_IV_LEN); 226 memmove(pos, pos + IEEE80211_TKIP_IV_LEN, hdrlen); 227 pos += hdrlen; 228 229 /* the HW only needs room for the IV, but not the actual IV */ 230 if (info->control.hw_key && 231 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) 232 return 0; 233 234 /* Increase IV for the frame */ 235 pn = atomic64_inc_return(&key->conf.tx_pn); 236 pos = ieee80211_tkip_add_iv(pos, &key->conf, pn); 237 238 /* hwaccel - with software IV */ 239 if (info->control.hw_key) 240 return 0; 241 242 /* Add room for ICV */ 243 skb_put(skb, IEEE80211_TKIP_ICV_LEN); 244 245 return ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm, 246 key, skb, pos, len); 247 } 248 249 250 ieee80211_tx_result 251 ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx) 252 { 253 struct sk_buff *skb; 254 255 ieee80211_tx_set_protected(tx); 256 257 skb_queue_walk(&tx->skbs, skb) { 258 if (tkip_encrypt_skb(tx, skb) < 0) 259 return TX_DROP; 260 } 261 262 return TX_CONTINUE; 263 } 264 265 266 ieee80211_rx_result 267 ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx) 268 { 269 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data; 270 int hdrlen, res, hwaccel = 0; 271 struct ieee80211_key *key = rx->key; 272 struct sk_buff *skb = rx->skb; 273 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 274 275 hdrlen = ieee80211_hdrlen(hdr->frame_control); 276 277 if (!ieee80211_is_data(hdr->frame_control)) 278 return RX_CONTINUE; 279 280 if (!rx->sta || skb->len - hdrlen < 12) 281 return RX_DROP_UNUSABLE; 282 283 /* it may be possible to optimize this a bit more */ 284 if (skb_linearize(rx->skb)) 285 return RX_DROP_UNUSABLE; 286 hdr = (void *)skb->data; 287 288 /* 289 * Let TKIP code verify IV, but skip decryption. 290 * In the case where hardware checks the IV as well, 291 * we don't even get here, see ieee80211_rx_h_decrypt() 292 */ 293 if (status->flag & RX_FLAG_DECRYPTED) 294 hwaccel = 1; 295 296 res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm, 297 key, skb->data + hdrlen, 298 skb->len - hdrlen, rx->sta->sta.addr, 299 hdr->addr1, hwaccel, rx->security_idx, 300 &rx->tkip_iv32, 301 &rx->tkip_iv16); 302 if (res != TKIP_DECRYPT_OK) 303 return RX_DROP_UNUSABLE; 304 305 /* Trim ICV */ 306 if (!(status->flag & RX_FLAG_ICV_STRIPPED)) 307 skb_trim(skb, skb->len - IEEE80211_TKIP_ICV_LEN); 308 309 /* Remove IV */ 310 memmove(skb->data + IEEE80211_TKIP_IV_LEN, skb->data, hdrlen); 311 skb_pull(skb, IEEE80211_TKIP_IV_LEN); 312 313 return RX_CONTINUE; 314 } 315 316 317 static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad) 318 { 319 __le16 mask_fc; 320 int a4_included, mgmt; 321 u8 qos_tid; 322 u16 len_a; 323 unsigned int hdrlen; 324 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 325 326 /* 327 * Mask FC: zero subtype b4 b5 b6 (if not mgmt) 328 * Retry, PwrMgt, MoreData; set Protected 329 */ 330 mgmt = ieee80211_is_mgmt(hdr->frame_control); 331 mask_fc = hdr->frame_control; 332 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | 333 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA); 334 if (!mgmt) 335 mask_fc &= ~cpu_to_le16(0x0070); 336 mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); 337 338 hdrlen = ieee80211_hdrlen(hdr->frame_control); 339 len_a = hdrlen - 2; 340 a4_included = ieee80211_has_a4(hdr->frame_control); 341 342 if (ieee80211_is_data_qos(hdr->frame_control)) 343 qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; 344 else 345 qos_tid = 0; 346 347 /* In CCM, the initial vectors (IV) used for CTR mode encryption and CBC 348 * mode authentication are not allowed to collide, yet both are derived 349 * from this vector b_0. We only set L := 1 here to indicate that the 350 * data size can be represented in (L+1) bytes. The CCM layer will take 351 * care of storing the data length in the top (L+1) bytes and setting 352 * and clearing the other bits as is required to derive the two IVs. 353 */ 354 b_0[0] = 0x1; 355 356 /* Nonce: Nonce Flags | A2 | PN 357 * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7) 358 */ 359 b_0[1] = qos_tid | (mgmt << 4); 360 memcpy(&b_0[2], hdr->addr2, ETH_ALEN); 361 memcpy(&b_0[8], pn, IEEE80211_CCMP_PN_LEN); 362 363 /* AAD (extra authenticate-only data) / masked 802.11 header 364 * FC | A1 | A2 | A3 | SC | [A4] | [QC] */ 365 put_unaligned_be16(len_a, &aad[0]); 366 put_unaligned(mask_fc, (__le16 *)&aad[2]); 367 memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN); 368 369 /* Mask Seq#, leave Frag# */ 370 aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f; 371 aad[23] = 0; 372 373 if (a4_included) { 374 memcpy(&aad[24], hdr->addr4, ETH_ALEN); 375 aad[30] = qos_tid; 376 aad[31] = 0; 377 } else { 378 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN); 379 aad[24] = qos_tid; 380 } 381 } 382 383 384 static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id) 385 { 386 hdr[0] = pn[5]; 387 hdr[1] = pn[4]; 388 hdr[2] = 0; 389 hdr[3] = 0x20 | (key_id << 6); 390 hdr[4] = pn[3]; 391 hdr[5] = pn[2]; 392 hdr[6] = pn[1]; 393 hdr[7] = pn[0]; 394 } 395 396 397 static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr) 398 { 399 pn[0] = hdr[7]; 400 pn[1] = hdr[6]; 401 pn[2] = hdr[5]; 402 pn[3] = hdr[4]; 403 pn[4] = hdr[1]; 404 pn[5] = hdr[0]; 405 } 406 407 408 static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb, 409 unsigned int mic_len) 410 { 411 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 412 struct ieee80211_key *key = tx->key; 413 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 414 int hdrlen, len, tail; 415 u8 *pos; 416 u8 pn[6]; 417 u64 pn64; 418 u8 aad[CCM_AAD_LEN]; 419 u8 b_0[AES_BLOCK_SIZE]; 420 421 if (info->control.hw_key && 422 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) && 423 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) && 424 !((info->control.hw_key->flags & 425 IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) && 426 ieee80211_is_mgmt(hdr->frame_control))) { 427 /* 428 * hwaccel has no need for preallocated room for CCMP 429 * header or MIC fields 430 */ 431 return 0; 432 } 433 434 hdrlen = ieee80211_hdrlen(hdr->frame_control); 435 len = skb->len - hdrlen; 436 437 if (info->control.hw_key) 438 tail = 0; 439 else 440 tail = mic_len; 441 442 if (WARN_ON(skb_tailroom(skb) < tail || 443 skb_headroom(skb) < IEEE80211_CCMP_HDR_LEN)) 444 return -1; 445 446 pos = skb_push(skb, IEEE80211_CCMP_HDR_LEN); 447 memmove(pos, pos + IEEE80211_CCMP_HDR_LEN, hdrlen); 448 449 /* the HW only needs room for the IV, but not the actual IV */ 450 if (info->control.hw_key && 451 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) 452 return 0; 453 454 hdr = (struct ieee80211_hdr *) pos; 455 pos += hdrlen; 456 457 pn64 = atomic64_inc_return(&key->conf.tx_pn); 458 459 pn[5] = pn64; 460 pn[4] = pn64 >> 8; 461 pn[3] = pn64 >> 16; 462 pn[2] = pn64 >> 24; 463 pn[1] = pn64 >> 32; 464 pn[0] = pn64 >> 40; 465 466 ccmp_pn2hdr(pos, pn, key->conf.keyidx); 467 468 /* hwaccel - with software CCMP header */ 469 if (info->control.hw_key) 470 return 0; 471 472 pos += IEEE80211_CCMP_HDR_LEN; 473 ccmp_special_blocks(skb, pn, b_0, aad); 474 return ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, b_0, aad, pos, len, 475 skb_put(skb, mic_len)); 476 } 477 478 479 ieee80211_tx_result 480 ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx, 481 unsigned int mic_len) 482 { 483 struct sk_buff *skb; 484 485 ieee80211_tx_set_protected(tx); 486 487 skb_queue_walk(&tx->skbs, skb) { 488 if (ccmp_encrypt_skb(tx, skb, mic_len) < 0) 489 return TX_DROP; 490 } 491 492 return TX_CONTINUE; 493 } 494 495 496 ieee80211_rx_result 497 ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx, 498 unsigned int mic_len) 499 { 500 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 501 int hdrlen; 502 struct ieee80211_key *key = rx->key; 503 struct sk_buff *skb = rx->skb; 504 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 505 u8 pn[IEEE80211_CCMP_PN_LEN]; 506 int data_len; 507 int queue; 508 509 hdrlen = ieee80211_hdrlen(hdr->frame_control); 510 511 if (!ieee80211_is_data(hdr->frame_control) && 512 !ieee80211_is_robust_mgmt_frame(skb)) 513 return RX_CONTINUE; 514 515 if (status->flag & RX_FLAG_DECRYPTED) { 516 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_CCMP_HDR_LEN)) 517 return RX_DROP_UNUSABLE; 518 if (status->flag & RX_FLAG_MIC_STRIPPED) 519 mic_len = 0; 520 } else { 521 if (skb_linearize(rx->skb)) 522 return RX_DROP_UNUSABLE; 523 } 524 525 data_len = skb->len - hdrlen - IEEE80211_CCMP_HDR_LEN - mic_len; 526 if (!rx->sta || data_len < 0) 527 return RX_DROP_UNUSABLE; 528 529 if (!(status->flag & RX_FLAG_PN_VALIDATED)) { 530 int res; 531 532 ccmp_hdr2pn(pn, skb->data + hdrlen); 533 534 queue = rx->security_idx; 535 536 res = memcmp(pn, key->u.ccmp.rx_pn[queue], 537 IEEE80211_CCMP_PN_LEN); 538 if (res < 0 || 539 (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) { 540 key->u.ccmp.replays++; 541 return RX_DROP_UNUSABLE; 542 } 543 544 if (!(status->flag & RX_FLAG_DECRYPTED)) { 545 u8 aad[2 * AES_BLOCK_SIZE]; 546 u8 b_0[AES_BLOCK_SIZE]; 547 /* hardware didn't decrypt/verify MIC */ 548 ccmp_special_blocks(skb, pn, b_0, aad); 549 550 if (ieee80211_aes_ccm_decrypt( 551 key->u.ccmp.tfm, b_0, aad, 552 skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN, 553 data_len, 554 skb->data + skb->len - mic_len)) 555 return RX_DROP_UNUSABLE; 556 } 557 558 memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN); 559 } 560 561 /* Remove CCMP header and MIC */ 562 if (pskb_trim(skb, skb->len - mic_len)) 563 return RX_DROP_UNUSABLE; 564 memmove(skb->data + IEEE80211_CCMP_HDR_LEN, skb->data, hdrlen); 565 skb_pull(skb, IEEE80211_CCMP_HDR_LEN); 566 567 return RX_CONTINUE; 568 } 569 570 static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad) 571 { 572 __le16 mask_fc; 573 u8 qos_tid; 574 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 575 576 memcpy(j_0, hdr->addr2, ETH_ALEN); 577 memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN); 578 j_0[13] = 0; 579 j_0[14] = 0; 580 j_0[AES_BLOCK_SIZE - 1] = 0x01; 581 582 /* AAD (extra authenticate-only data) / masked 802.11 header 583 * FC | A1 | A2 | A3 | SC | [A4] | [QC] 584 */ 585 put_unaligned_be16(ieee80211_hdrlen(hdr->frame_control) - 2, &aad[0]); 586 /* Mask FC: zero subtype b4 b5 b6 (if not mgmt) 587 * Retry, PwrMgt, MoreData; set Protected 588 */ 589 mask_fc = hdr->frame_control; 590 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | 591 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA); 592 if (!ieee80211_is_mgmt(hdr->frame_control)) 593 mask_fc &= ~cpu_to_le16(0x0070); 594 mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); 595 596 put_unaligned(mask_fc, (__le16 *)&aad[2]); 597 memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN); 598 599 /* Mask Seq#, leave Frag# */ 600 aad[22] = *((u8 *)&hdr->seq_ctrl) & 0x0f; 601 aad[23] = 0; 602 603 if (ieee80211_is_data_qos(hdr->frame_control)) 604 qos_tid = *ieee80211_get_qos_ctl(hdr) & 605 IEEE80211_QOS_CTL_TID_MASK; 606 else 607 qos_tid = 0; 608 609 if (ieee80211_has_a4(hdr->frame_control)) { 610 memcpy(&aad[24], hdr->addr4, ETH_ALEN); 611 aad[30] = qos_tid; 612 aad[31] = 0; 613 } else { 614 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN); 615 aad[24] = qos_tid; 616 } 617 } 618 619 static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id) 620 { 621 hdr[0] = pn[5]; 622 hdr[1] = pn[4]; 623 hdr[2] = 0; 624 hdr[3] = 0x20 | (key_id << 6); 625 hdr[4] = pn[3]; 626 hdr[5] = pn[2]; 627 hdr[6] = pn[1]; 628 hdr[7] = pn[0]; 629 } 630 631 static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr) 632 { 633 pn[0] = hdr[7]; 634 pn[1] = hdr[6]; 635 pn[2] = hdr[5]; 636 pn[3] = hdr[4]; 637 pn[4] = hdr[1]; 638 pn[5] = hdr[0]; 639 } 640 641 static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) 642 { 643 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 644 struct ieee80211_key *key = tx->key; 645 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 646 int hdrlen, len, tail; 647 u8 *pos; 648 u8 pn[6]; 649 u64 pn64; 650 u8 aad[GCM_AAD_LEN]; 651 u8 j_0[AES_BLOCK_SIZE]; 652 653 if (info->control.hw_key && 654 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) && 655 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) && 656 !((info->control.hw_key->flags & 657 IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) && 658 ieee80211_is_mgmt(hdr->frame_control))) { 659 /* hwaccel has no need for preallocated room for GCMP 660 * header or MIC fields 661 */ 662 return 0; 663 } 664 665 hdrlen = ieee80211_hdrlen(hdr->frame_control); 666 len = skb->len - hdrlen; 667 668 if (info->control.hw_key) 669 tail = 0; 670 else 671 tail = IEEE80211_GCMP_MIC_LEN; 672 673 if (WARN_ON(skb_tailroom(skb) < tail || 674 skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN)) 675 return -1; 676 677 pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN); 678 memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen); 679 skb_set_network_header(skb, skb_network_offset(skb) + 680 IEEE80211_GCMP_HDR_LEN); 681 682 /* the HW only needs room for the IV, but not the actual IV */ 683 if (info->control.hw_key && 684 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) 685 return 0; 686 687 hdr = (struct ieee80211_hdr *)pos; 688 pos += hdrlen; 689 690 pn64 = atomic64_inc_return(&key->conf.tx_pn); 691 692 pn[5] = pn64; 693 pn[4] = pn64 >> 8; 694 pn[3] = pn64 >> 16; 695 pn[2] = pn64 >> 24; 696 pn[1] = pn64 >> 32; 697 pn[0] = pn64 >> 40; 698 699 gcmp_pn2hdr(pos, pn, key->conf.keyidx); 700 701 /* hwaccel - with software GCMP header */ 702 if (info->control.hw_key) 703 return 0; 704 705 pos += IEEE80211_GCMP_HDR_LEN; 706 gcmp_special_blocks(skb, pn, j_0, aad); 707 return ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len, 708 skb_put(skb, IEEE80211_GCMP_MIC_LEN)); 709 } 710 711 ieee80211_tx_result 712 ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx) 713 { 714 struct sk_buff *skb; 715 716 ieee80211_tx_set_protected(tx); 717 718 skb_queue_walk(&tx->skbs, skb) { 719 if (gcmp_encrypt_skb(tx, skb) < 0) 720 return TX_DROP; 721 } 722 723 return TX_CONTINUE; 724 } 725 726 ieee80211_rx_result 727 ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx) 728 { 729 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 730 int hdrlen; 731 struct ieee80211_key *key = rx->key; 732 struct sk_buff *skb = rx->skb; 733 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 734 u8 pn[IEEE80211_GCMP_PN_LEN]; 735 int data_len, queue, mic_len = IEEE80211_GCMP_MIC_LEN; 736 737 hdrlen = ieee80211_hdrlen(hdr->frame_control); 738 739 if (!ieee80211_is_data(hdr->frame_control) && 740 !ieee80211_is_robust_mgmt_frame(skb)) 741 return RX_CONTINUE; 742 743 if (status->flag & RX_FLAG_DECRYPTED) { 744 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN)) 745 return RX_DROP_UNUSABLE; 746 if (status->flag & RX_FLAG_MIC_STRIPPED) 747 mic_len = 0; 748 } else { 749 if (skb_linearize(rx->skb)) 750 return RX_DROP_UNUSABLE; 751 } 752 753 data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN - mic_len; 754 if (!rx->sta || data_len < 0) 755 return RX_DROP_UNUSABLE; 756 757 if (!(status->flag & RX_FLAG_PN_VALIDATED)) { 758 int res; 759 760 gcmp_hdr2pn(pn, skb->data + hdrlen); 761 762 queue = rx->security_idx; 763 764 res = memcmp(pn, key->u.gcmp.rx_pn[queue], 765 IEEE80211_GCMP_PN_LEN); 766 if (res < 0 || 767 (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) { 768 key->u.gcmp.replays++; 769 return RX_DROP_UNUSABLE; 770 } 771 772 if (!(status->flag & RX_FLAG_DECRYPTED)) { 773 u8 aad[2 * AES_BLOCK_SIZE]; 774 u8 j_0[AES_BLOCK_SIZE]; 775 /* hardware didn't decrypt/verify MIC */ 776 gcmp_special_blocks(skb, pn, j_0, aad); 777 778 if (ieee80211_aes_gcm_decrypt( 779 key->u.gcmp.tfm, j_0, aad, 780 skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN, 781 data_len, 782 skb->data + skb->len - 783 IEEE80211_GCMP_MIC_LEN)) 784 return RX_DROP_UNUSABLE; 785 } 786 787 memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN); 788 } 789 790 /* Remove GCMP header and MIC */ 791 if (pskb_trim(skb, skb->len - mic_len)) 792 return RX_DROP_UNUSABLE; 793 memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen); 794 skb_pull(skb, IEEE80211_GCMP_HDR_LEN); 795 796 return RX_CONTINUE; 797 } 798 799 static ieee80211_tx_result 800 ieee80211_crypto_cs_encrypt(struct ieee80211_tx_data *tx, 801 struct sk_buff *skb) 802 { 803 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 804 struct ieee80211_key *key = tx->key; 805 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 806 int hdrlen; 807 u8 *pos, iv_len = key->conf.iv_len; 808 809 if (info->control.hw_key && 810 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) { 811 /* hwaccel has no need for preallocated head room */ 812 return TX_CONTINUE; 813 } 814 815 if (unlikely(skb_headroom(skb) < iv_len && 816 pskb_expand_head(skb, iv_len, 0, GFP_ATOMIC))) 817 return TX_DROP; 818 819 hdrlen = ieee80211_hdrlen(hdr->frame_control); 820 821 pos = skb_push(skb, iv_len); 822 memmove(pos, pos + iv_len, hdrlen); 823 824 return TX_CONTINUE; 825 } 826 827 static inline int ieee80211_crypto_cs_pn_compare(u8 *pn1, u8 *pn2, int len) 828 { 829 int i; 830 831 /* pn is little endian */ 832 for (i = len - 1; i >= 0; i--) { 833 if (pn1[i] < pn2[i]) 834 return -1; 835 else if (pn1[i] > pn2[i]) 836 return 1; 837 } 838 839 return 0; 840 } 841 842 static ieee80211_rx_result 843 ieee80211_crypto_cs_decrypt(struct ieee80211_rx_data *rx) 844 { 845 struct ieee80211_key *key = rx->key; 846 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 847 const struct ieee80211_cipher_scheme *cs = NULL; 848 int hdrlen = ieee80211_hdrlen(hdr->frame_control); 849 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 850 int data_len; 851 u8 *rx_pn; 852 u8 *skb_pn; 853 u8 qos_tid; 854 855 if (!rx->sta || !rx->sta->cipher_scheme || 856 !(status->flag & RX_FLAG_DECRYPTED)) 857 return RX_DROP_UNUSABLE; 858 859 if (!ieee80211_is_data(hdr->frame_control)) 860 return RX_CONTINUE; 861 862 cs = rx->sta->cipher_scheme; 863 864 data_len = rx->skb->len - hdrlen - cs->hdr_len; 865 866 if (data_len < 0) 867 return RX_DROP_UNUSABLE; 868 869 if (ieee80211_is_data_qos(hdr->frame_control)) 870 qos_tid = *ieee80211_get_qos_ctl(hdr) & 871 IEEE80211_QOS_CTL_TID_MASK; 872 else 873 qos_tid = 0; 874 875 if (skb_linearize(rx->skb)) 876 return RX_DROP_UNUSABLE; 877 878 hdr = (struct ieee80211_hdr *)rx->skb->data; 879 880 rx_pn = key->u.gen.rx_pn[qos_tid]; 881 skb_pn = rx->skb->data + hdrlen + cs->pn_off; 882 883 if (ieee80211_crypto_cs_pn_compare(skb_pn, rx_pn, cs->pn_len) <= 0) 884 return RX_DROP_UNUSABLE; 885 886 memcpy(rx_pn, skb_pn, cs->pn_len); 887 888 /* remove security header and MIC */ 889 if (pskb_trim(rx->skb, rx->skb->len - cs->mic_len)) 890 return RX_DROP_UNUSABLE; 891 892 memmove(rx->skb->data + cs->hdr_len, rx->skb->data, hdrlen); 893 skb_pull(rx->skb, cs->hdr_len); 894 895 return RX_CONTINUE; 896 } 897 898 static void bip_aad(struct sk_buff *skb, u8 *aad) 899 { 900 __le16 mask_fc; 901 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 902 903 /* BIP AAD: FC(masked) || A1 || A2 || A3 */ 904 905 /* FC type/subtype */ 906 /* Mask FC Retry, PwrMgt, MoreData flags to zero */ 907 mask_fc = hdr->frame_control; 908 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM | 909 IEEE80211_FCTL_MOREDATA); 910 put_unaligned(mask_fc, (__le16 *) &aad[0]); 911 /* A1 || A2 || A3 */ 912 memcpy(aad + 2, &hdr->addr1, 3 * ETH_ALEN); 913 } 914 915 916 static inline void bip_ipn_set64(u8 *d, u64 pn) 917 { 918 *d++ = pn; 919 *d++ = pn >> 8; 920 *d++ = pn >> 16; 921 *d++ = pn >> 24; 922 *d++ = pn >> 32; 923 *d = pn >> 40; 924 } 925 926 static inline void bip_ipn_swap(u8 *d, const u8 *s) 927 { 928 *d++ = s[5]; 929 *d++ = s[4]; 930 *d++ = s[3]; 931 *d++ = s[2]; 932 *d++ = s[1]; 933 *d = s[0]; 934 } 935 936 937 ieee80211_tx_result 938 ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx) 939 { 940 struct sk_buff *skb; 941 struct ieee80211_tx_info *info; 942 struct ieee80211_key *key = tx->key; 943 struct ieee80211_mmie *mmie; 944 u8 aad[20]; 945 u64 pn64; 946 947 if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) 948 return TX_DROP; 949 950 skb = skb_peek(&tx->skbs); 951 952 info = IEEE80211_SKB_CB(skb); 953 954 if (info->control.hw_key) 955 return TX_CONTINUE; 956 957 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) 958 return TX_DROP; 959 960 mmie = skb_put(skb, sizeof(*mmie)); 961 mmie->element_id = WLAN_EID_MMIE; 962 mmie->length = sizeof(*mmie) - 2; 963 mmie->key_id = cpu_to_le16(key->conf.keyidx); 964 965 /* PN = PN + 1 */ 966 pn64 = atomic64_inc_return(&key->conf.tx_pn); 967 968 bip_ipn_set64(mmie->sequence_number, pn64); 969 970 bip_aad(skb, aad); 971 972 /* 973 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64) 974 */ 975 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad, 976 skb->data + 24, skb->len - 24, mmie->mic); 977 978 return TX_CONTINUE; 979 } 980 981 ieee80211_tx_result 982 ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx) 983 { 984 struct sk_buff *skb; 985 struct ieee80211_tx_info *info; 986 struct ieee80211_key *key = tx->key; 987 struct ieee80211_mmie_16 *mmie; 988 u8 aad[20]; 989 u64 pn64; 990 991 if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) 992 return TX_DROP; 993 994 skb = skb_peek(&tx->skbs); 995 996 info = IEEE80211_SKB_CB(skb); 997 998 if (info->control.hw_key) 999 return TX_CONTINUE; 1000 1001 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) 1002 return TX_DROP; 1003 1004 mmie = skb_put(skb, sizeof(*mmie)); 1005 mmie->element_id = WLAN_EID_MMIE; 1006 mmie->length = sizeof(*mmie) - 2; 1007 mmie->key_id = cpu_to_le16(key->conf.keyidx); 1008 1009 /* PN = PN + 1 */ 1010 pn64 = atomic64_inc_return(&key->conf.tx_pn); 1011 1012 bip_ipn_set64(mmie->sequence_number, pn64); 1013 1014 bip_aad(skb, aad); 1015 1016 /* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128) 1017 */ 1018 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad, 1019 skb->data + 24, skb->len - 24, mmie->mic); 1020 1021 return TX_CONTINUE; 1022 } 1023 1024 ieee80211_rx_result 1025 ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx) 1026 { 1027 struct sk_buff *skb = rx->skb; 1028 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1029 struct ieee80211_key *key = rx->key; 1030 struct ieee80211_mmie *mmie; 1031 u8 aad[20], mic[8], ipn[6]; 1032 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1033 1034 if (!ieee80211_is_mgmt(hdr->frame_control)) 1035 return RX_CONTINUE; 1036 1037 /* management frames are already linear */ 1038 1039 if (skb->len < 24 + sizeof(*mmie)) 1040 return RX_DROP_UNUSABLE; 1041 1042 mmie = (struct ieee80211_mmie *) 1043 (skb->data + skb->len - sizeof(*mmie)); 1044 if (mmie->element_id != WLAN_EID_MMIE || 1045 mmie->length != sizeof(*mmie) - 2) 1046 return RX_DROP_UNUSABLE; /* Invalid MMIE */ 1047 1048 bip_ipn_swap(ipn, mmie->sequence_number); 1049 1050 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) { 1051 key->u.aes_cmac.replays++; 1052 return RX_DROP_UNUSABLE; 1053 } 1054 1055 if (!(status->flag & RX_FLAG_DECRYPTED)) { 1056 /* hardware didn't decrypt/verify MIC */ 1057 bip_aad(skb, aad); 1058 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad, 1059 skb->data + 24, skb->len - 24, mic); 1060 if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) { 1061 key->u.aes_cmac.icverrors++; 1062 return RX_DROP_UNUSABLE; 1063 } 1064 } 1065 1066 memcpy(key->u.aes_cmac.rx_pn, ipn, 6); 1067 1068 /* Remove MMIE */ 1069 skb_trim(skb, skb->len - sizeof(*mmie)); 1070 1071 return RX_CONTINUE; 1072 } 1073 1074 ieee80211_rx_result 1075 ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx) 1076 { 1077 struct sk_buff *skb = rx->skb; 1078 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1079 struct ieee80211_key *key = rx->key; 1080 struct ieee80211_mmie_16 *mmie; 1081 u8 aad[20], mic[16], ipn[6]; 1082 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1083 1084 if (!ieee80211_is_mgmt(hdr->frame_control)) 1085 return RX_CONTINUE; 1086 1087 /* management frames are already linear */ 1088 1089 if (skb->len < 24 + sizeof(*mmie)) 1090 return RX_DROP_UNUSABLE; 1091 1092 mmie = (struct ieee80211_mmie_16 *) 1093 (skb->data + skb->len - sizeof(*mmie)); 1094 if (mmie->element_id != WLAN_EID_MMIE || 1095 mmie->length != sizeof(*mmie) - 2) 1096 return RX_DROP_UNUSABLE; /* Invalid MMIE */ 1097 1098 bip_ipn_swap(ipn, mmie->sequence_number); 1099 1100 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) { 1101 key->u.aes_cmac.replays++; 1102 return RX_DROP_UNUSABLE; 1103 } 1104 1105 if (!(status->flag & RX_FLAG_DECRYPTED)) { 1106 /* hardware didn't decrypt/verify MIC */ 1107 bip_aad(skb, aad); 1108 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad, 1109 skb->data + 24, skb->len - 24, mic); 1110 if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) { 1111 key->u.aes_cmac.icverrors++; 1112 return RX_DROP_UNUSABLE; 1113 } 1114 } 1115 1116 memcpy(key->u.aes_cmac.rx_pn, ipn, 6); 1117 1118 /* Remove MMIE */ 1119 skb_trim(skb, skb->len - sizeof(*mmie)); 1120 1121 return RX_CONTINUE; 1122 } 1123 1124 ieee80211_tx_result 1125 ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx) 1126 { 1127 struct sk_buff *skb; 1128 struct ieee80211_tx_info *info; 1129 struct ieee80211_key *key = tx->key; 1130 struct ieee80211_mmie_16 *mmie; 1131 struct ieee80211_hdr *hdr; 1132 u8 aad[GMAC_AAD_LEN]; 1133 u64 pn64; 1134 u8 nonce[GMAC_NONCE_LEN]; 1135 1136 if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) 1137 return TX_DROP; 1138 1139 skb = skb_peek(&tx->skbs); 1140 1141 info = IEEE80211_SKB_CB(skb); 1142 1143 if (info->control.hw_key) 1144 return TX_CONTINUE; 1145 1146 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) 1147 return TX_DROP; 1148 1149 mmie = skb_put(skb, sizeof(*mmie)); 1150 mmie->element_id = WLAN_EID_MMIE; 1151 mmie->length = sizeof(*mmie) - 2; 1152 mmie->key_id = cpu_to_le16(key->conf.keyidx); 1153 1154 /* PN = PN + 1 */ 1155 pn64 = atomic64_inc_return(&key->conf.tx_pn); 1156 1157 bip_ipn_set64(mmie->sequence_number, pn64); 1158 1159 bip_aad(skb, aad); 1160 1161 hdr = (struct ieee80211_hdr *)skb->data; 1162 memcpy(nonce, hdr->addr2, ETH_ALEN); 1163 bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number); 1164 1165 /* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */ 1166 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce, 1167 skb->data + 24, skb->len - 24, mmie->mic) < 0) 1168 return TX_DROP; 1169 1170 return TX_CONTINUE; 1171 } 1172 1173 ieee80211_rx_result 1174 ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx) 1175 { 1176 struct sk_buff *skb = rx->skb; 1177 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1178 struct ieee80211_key *key = rx->key; 1179 struct ieee80211_mmie_16 *mmie; 1180 u8 aad[GMAC_AAD_LEN], mic[GMAC_MIC_LEN], ipn[6], nonce[GMAC_NONCE_LEN]; 1181 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1182 1183 if (!ieee80211_is_mgmt(hdr->frame_control)) 1184 return RX_CONTINUE; 1185 1186 /* management frames are already linear */ 1187 1188 if (skb->len < 24 + sizeof(*mmie)) 1189 return RX_DROP_UNUSABLE; 1190 1191 mmie = (struct ieee80211_mmie_16 *) 1192 (skb->data + skb->len - sizeof(*mmie)); 1193 if (mmie->element_id != WLAN_EID_MMIE || 1194 mmie->length != sizeof(*mmie) - 2) 1195 return RX_DROP_UNUSABLE; /* Invalid MMIE */ 1196 1197 bip_ipn_swap(ipn, mmie->sequence_number); 1198 1199 if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) { 1200 key->u.aes_gmac.replays++; 1201 return RX_DROP_UNUSABLE; 1202 } 1203 1204 if (!(status->flag & RX_FLAG_DECRYPTED)) { 1205 /* hardware didn't decrypt/verify MIC */ 1206 bip_aad(skb, aad); 1207 1208 memcpy(nonce, hdr->addr2, ETH_ALEN); 1209 memcpy(nonce + ETH_ALEN, ipn, 6); 1210 1211 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce, 1212 skb->data + 24, skb->len - 24, 1213 mic) < 0 || 1214 crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) { 1215 key->u.aes_gmac.icverrors++; 1216 return RX_DROP_UNUSABLE; 1217 } 1218 } 1219 1220 memcpy(key->u.aes_gmac.rx_pn, ipn, 6); 1221 1222 /* Remove MMIE */ 1223 skb_trim(skb, skb->len - sizeof(*mmie)); 1224 1225 return RX_CONTINUE; 1226 } 1227 1228 ieee80211_tx_result 1229 ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx) 1230 { 1231 struct sk_buff *skb; 1232 struct ieee80211_tx_info *info = NULL; 1233 ieee80211_tx_result res; 1234 1235 skb_queue_walk(&tx->skbs, skb) { 1236 info = IEEE80211_SKB_CB(skb); 1237 1238 /* handle hw-only algorithm */ 1239 if (!info->control.hw_key) 1240 return TX_DROP; 1241 1242 if (tx->key->flags & KEY_FLAG_CIPHER_SCHEME) { 1243 res = ieee80211_crypto_cs_encrypt(tx, skb); 1244 if (res != TX_CONTINUE) 1245 return res; 1246 } 1247 } 1248 1249 ieee80211_tx_set_protected(tx); 1250 1251 return TX_CONTINUE; 1252 } 1253 1254 ieee80211_rx_result 1255 ieee80211_crypto_hw_decrypt(struct ieee80211_rx_data *rx) 1256 { 1257 if (rx->sta && rx->sta->cipher_scheme) 1258 return ieee80211_crypto_cs_decrypt(rx); 1259 1260 return RX_DROP_UNUSABLE; 1261 } 1262