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