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