1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright 2002-2004, Instant802 Networks, Inc. 4 * Copyright 2008, Jouni Malinen <j@w1.fi> 5 * Copyright (C) 2016-2017 Intel Deutschland GmbH 6 * Copyright (C) 2020-2021 Intel Corporation 7 */ 8 9 #include <linux/netdevice.h> 10 #include <linux/types.h> 11 #include <linux/skbuff.h> 12 #include <linux/compiler.h> 13 #include <linux/ieee80211.h> 14 #include <linux/gfp.h> 15 #include <asm/unaligned.h> 16 #include <net/mac80211.h> 17 #include <crypto/aes.h> 18 #include <crypto/algapi.h> 19 20 #include "ieee80211_i.h" 21 #include "michael.h" 22 #include "tkip.h" 23 #include "aes_ccm.h" 24 #include "aes_cmac.h" 25 #include "aes_gmac.h" 26 #include "aes_gcm.h" 27 #include "wpa.h" 28 29 ieee80211_tx_result 30 ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx) 31 { 32 u8 *data, *key, *mic; 33 size_t data_len; 34 unsigned int hdrlen; 35 struct ieee80211_hdr *hdr; 36 struct sk_buff *skb = tx->skb; 37 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 38 int tail; 39 40 hdr = (struct ieee80211_hdr *)skb->data; 41 if (!tx->key || tx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP || 42 skb->len < 24 || !ieee80211_is_data_present(hdr->frame_control)) 43 return TX_CONTINUE; 44 45 hdrlen = ieee80211_hdrlen(hdr->frame_control); 46 if (skb->len < hdrlen) 47 return TX_DROP; 48 49 data = skb->data + hdrlen; 50 data_len = skb->len - hdrlen; 51 52 if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) { 53 /* Need to use software crypto for the test */ 54 info->control.hw_key = NULL; 55 } 56 57 if (info->control.hw_key && 58 (info->flags & IEEE80211_TX_CTL_DONTFRAG || 59 ieee80211_hw_check(&tx->local->hw, SUPPORTS_TX_FRAG)) && 60 !(tx->key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC | 61 IEEE80211_KEY_FLAG_PUT_MIC_SPACE))) { 62 /* hwaccel - with no need for SW-generated MMIC or MIC space */ 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 mic = skb_put(skb, MICHAEL_MIC_LEN); 78 79 if (tx->key->conf.flags & IEEE80211_KEY_FLAG_PUT_MIC_SPACE) { 80 /* Zeroed MIC can help with debug */ 81 memset(mic, 0, MICHAEL_MIC_LEN); 82 return TX_CONTINUE; 83 } 84 85 key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY]; 86 michael_mic(key, hdr, data, data_len, mic); 87 if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) 88 mic[0]++; 89 90 return TX_CONTINUE; 91 } 92 93 94 ieee80211_rx_result 95 ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx) 96 { 97 u8 *data, *key = NULL; 98 size_t data_len; 99 unsigned int hdrlen; 100 u8 mic[MICHAEL_MIC_LEN]; 101 struct sk_buff *skb = rx->skb; 102 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 103 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 104 105 /* 106 * it makes no sense to check for MIC errors on anything other 107 * than data frames. 108 */ 109 if (!ieee80211_is_data_present(hdr->frame_control)) 110 return RX_CONTINUE; 111 112 /* 113 * No way to verify the MIC if the hardware stripped it or 114 * the IV with the key index. In this case we have solely rely 115 * on the driver to set RX_FLAG_MMIC_ERROR in the event of a 116 * MIC failure report. 117 */ 118 if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) { 119 if (status->flag & RX_FLAG_MMIC_ERROR) 120 goto mic_fail_no_key; 121 122 if (!(status->flag & RX_FLAG_IV_STRIPPED) && rx->key && 123 rx->key->conf.cipher == WLAN_CIPHER_SUITE_TKIP) 124 goto update_iv; 125 126 return RX_CONTINUE; 127 } 128 129 /* 130 * Some hardware seems to generate Michael MIC failure reports; even 131 * though, the frame was not encrypted with TKIP and therefore has no 132 * MIC. Ignore the flag them to avoid triggering countermeasures. 133 */ 134 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP || 135 !(status->flag & RX_FLAG_DECRYPTED)) 136 return RX_CONTINUE; 137 138 if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) { 139 /* 140 * APs with pairwise keys should never receive Michael MIC 141 * errors for non-zero keyidx because these are reserved for 142 * group keys and only the AP is sending real multicast 143 * frames in the BSS. 144 */ 145 return RX_DROP_UNUSABLE; 146 } 147 148 if (status->flag & RX_FLAG_MMIC_ERROR) 149 goto mic_fail; 150 151 hdrlen = ieee80211_hdrlen(hdr->frame_control); 152 if (skb->len < hdrlen + MICHAEL_MIC_LEN) 153 return RX_DROP_UNUSABLE; 154 155 if (skb_linearize(rx->skb)) 156 return RX_DROP_UNUSABLE; 157 hdr = (void *)skb->data; 158 159 data = skb->data + hdrlen; 160 data_len = skb->len - hdrlen - MICHAEL_MIC_LEN; 161 key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY]; 162 michael_mic(key, hdr, data, data_len, mic); 163 if (crypto_memneq(mic, data + data_len, MICHAEL_MIC_LEN)) 164 goto mic_fail; 165 166 /* remove Michael MIC from payload */ 167 skb_trim(skb, skb->len - MICHAEL_MIC_LEN); 168 169 update_iv: 170 /* update IV in key information to be able to detect replays */ 171 rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip.iv32; 172 rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip.iv16; 173 174 return RX_CONTINUE; 175 176 mic_fail: 177 rx->key->u.tkip.mic_failures++; 178 179 mic_fail_no_key: 180 /* 181 * In some cases the key can be unset - e.g. a multicast packet, in 182 * a driver that supports HW encryption. Send up the key idx only if 183 * the key is set. 184 */ 185 cfg80211_michael_mic_failure(rx->sdata->dev, hdr->addr2, 186 is_multicast_ether_addr(hdr->addr1) ? 187 NL80211_KEYTYPE_GROUP : 188 NL80211_KEYTYPE_PAIRWISE, 189 rx->key ? rx->key->conf.keyidx : -1, 190 NULL, GFP_ATOMIC); 191 return RX_DROP_UNUSABLE; 192 } 193 194 static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) 195 { 196 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 197 struct ieee80211_key *key = tx->key; 198 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 199 unsigned int hdrlen; 200 int len, tail; 201 u64 pn; 202 u8 *pos; 203 204 if (info->control.hw_key && 205 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) && 206 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) { 207 /* hwaccel - with no need for software-generated IV */ 208 return 0; 209 } 210 211 hdrlen = ieee80211_hdrlen(hdr->frame_control); 212 len = skb->len - hdrlen; 213 214 if (info->control.hw_key) 215 tail = 0; 216 else 217 tail = IEEE80211_TKIP_ICV_LEN; 218 219 if (WARN_ON(skb_tailroom(skb) < tail || 220 skb_headroom(skb) < IEEE80211_TKIP_IV_LEN)) 221 return -1; 222 223 pos = skb_push(skb, IEEE80211_TKIP_IV_LEN); 224 memmove(pos, pos + IEEE80211_TKIP_IV_LEN, hdrlen); 225 pos += hdrlen; 226 227 /* the HW only needs room for the IV, but not the actual IV */ 228 if (info->control.hw_key && 229 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) 230 return 0; 231 232 /* Increase IV for the frame */ 233 pn = atomic64_inc_return(&key->conf.tx_pn); 234 pos = ieee80211_tkip_add_iv(pos, &key->conf, pn); 235 236 /* hwaccel - with software IV */ 237 if (info->control.hw_key) 238 return 0; 239 240 /* Add room for ICV */ 241 skb_put(skb, IEEE80211_TKIP_ICV_LEN); 242 243 return ieee80211_tkip_encrypt_data(&tx->local->wep_tx_ctx, 244 key, skb, pos, len); 245 } 246 247 248 ieee80211_tx_result 249 ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx) 250 { 251 struct sk_buff *skb; 252 253 ieee80211_tx_set_protected(tx); 254 255 skb_queue_walk(&tx->skbs, skb) { 256 if (tkip_encrypt_skb(tx, skb) < 0) 257 return TX_DROP; 258 } 259 260 return TX_CONTINUE; 261 } 262 263 264 ieee80211_rx_result 265 ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx) 266 { 267 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data; 268 int hdrlen, res, hwaccel = 0; 269 struct ieee80211_key *key = rx->key; 270 struct sk_buff *skb = rx->skb; 271 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 272 273 hdrlen = ieee80211_hdrlen(hdr->frame_control); 274 275 if (!ieee80211_is_data(hdr->frame_control)) 276 return RX_CONTINUE; 277 278 if (!rx->sta || skb->len - hdrlen < 12) 279 return RX_DROP_UNUSABLE; 280 281 /* it may be possible to optimize this a bit more */ 282 if (skb_linearize(rx->skb)) 283 return RX_DROP_UNUSABLE; 284 hdr = (void *)skb->data; 285 286 /* 287 * Let TKIP code verify IV, but skip decryption. 288 * In the case where hardware checks the IV as well, 289 * we don't even get here, see ieee80211_rx_h_decrypt() 290 */ 291 if (status->flag & RX_FLAG_DECRYPTED) 292 hwaccel = 1; 293 294 res = ieee80211_tkip_decrypt_data(&rx->local->wep_rx_ctx, 295 key, skb->data + hdrlen, 296 skb->len - hdrlen, rx->sta->sta.addr, 297 hdr->addr1, hwaccel, rx->security_idx, 298 &rx->tkip.iv32, 299 &rx->tkip.iv16); 300 if (res != TKIP_DECRYPT_OK) 301 return RX_DROP_UNUSABLE; 302 303 /* Trim ICV */ 304 if (!(status->flag & RX_FLAG_ICV_STRIPPED)) 305 skb_trim(skb, skb->len - IEEE80211_TKIP_ICV_LEN); 306 307 /* Remove IV */ 308 memmove(skb->data + IEEE80211_TKIP_IV_LEN, skb->data, hdrlen); 309 skb_pull(skb, IEEE80211_TKIP_IV_LEN); 310 311 return RX_CONTINUE; 312 } 313 314 315 static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad) 316 { 317 __le16 mask_fc; 318 int a4_included, mgmt; 319 u8 qos_tid; 320 u16 len_a; 321 unsigned int hdrlen; 322 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 323 324 /* 325 * Mask FC: zero subtype b4 b5 b6 (if not mgmt) 326 * Retry, PwrMgt, MoreData; set Protected 327 */ 328 mgmt = ieee80211_is_mgmt(hdr->frame_control); 329 mask_fc = hdr->frame_control; 330 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | 331 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA); 332 if (!mgmt) 333 mask_fc &= ~cpu_to_le16(0x0070); 334 mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); 335 336 hdrlen = ieee80211_hdrlen(hdr->frame_control); 337 len_a = hdrlen - 2; 338 a4_included = ieee80211_has_a4(hdr->frame_control); 339 340 if (ieee80211_is_data_qos(hdr->frame_control)) 341 qos_tid = ieee80211_get_tid(hdr); 342 else 343 qos_tid = 0; 344 345 /* In CCM, the initial vectors (IV) used for CTR mode encryption and CBC 346 * mode authentication are not allowed to collide, yet both are derived 347 * from this vector b_0. We only set L := 1 here to indicate that the 348 * data size can be represented in (L+1) bytes. The CCM layer will take 349 * care of storing the data length in the top (L+1) bytes and setting 350 * and clearing the other bits as is required to derive the two IVs. 351 */ 352 b_0[0] = 0x1; 353 354 /* Nonce: Nonce Flags | A2 | PN 355 * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7) 356 */ 357 b_0[1] = qos_tid | (mgmt << 4); 358 memcpy(&b_0[2], hdr->addr2, ETH_ALEN); 359 memcpy(&b_0[8], pn, IEEE80211_CCMP_PN_LEN); 360 361 /* AAD (extra authenticate-only data) / masked 802.11 header 362 * FC | A1 | A2 | A3 | SC | [A4] | [QC] */ 363 put_unaligned_be16(len_a, &aad[0]); 364 put_unaligned(mask_fc, (__le16 *)&aad[2]); 365 memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN); 366 367 /* Mask Seq#, leave Frag# */ 368 aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f; 369 aad[23] = 0; 370 371 if (a4_included) { 372 memcpy(&aad[24], hdr->addr4, ETH_ALEN); 373 aad[30] = qos_tid; 374 aad[31] = 0; 375 } else { 376 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN); 377 aad[24] = qos_tid; 378 } 379 } 380 381 382 static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id) 383 { 384 hdr[0] = pn[5]; 385 hdr[1] = pn[4]; 386 hdr[2] = 0; 387 hdr[3] = 0x20 | (key_id << 6); 388 hdr[4] = pn[3]; 389 hdr[5] = pn[2]; 390 hdr[6] = pn[1]; 391 hdr[7] = pn[0]; 392 } 393 394 395 static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr) 396 { 397 pn[0] = hdr[7]; 398 pn[1] = hdr[6]; 399 pn[2] = hdr[5]; 400 pn[3] = hdr[4]; 401 pn[4] = hdr[1]; 402 pn[5] = hdr[0]; 403 } 404 405 406 static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb, 407 unsigned int mic_len) 408 { 409 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 410 struct ieee80211_key *key = tx->key; 411 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 412 int hdrlen, len, tail; 413 u8 *pos; 414 u8 pn[6]; 415 u64 pn64; 416 u8 aad[CCM_AAD_LEN]; 417 u8 b_0[AES_BLOCK_SIZE]; 418 419 if (info->control.hw_key && 420 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) && 421 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) && 422 !((info->control.hw_key->flags & 423 IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) && 424 ieee80211_is_mgmt(hdr->frame_control))) { 425 /* 426 * hwaccel has no need for preallocated room for CCMP 427 * header or MIC fields 428 */ 429 return 0; 430 } 431 432 hdrlen = ieee80211_hdrlen(hdr->frame_control); 433 len = skb->len - hdrlen; 434 435 if (info->control.hw_key) 436 tail = 0; 437 else 438 tail = mic_len; 439 440 if (WARN_ON(skb_tailroom(skb) < tail || 441 skb_headroom(skb) < IEEE80211_CCMP_HDR_LEN)) 442 return -1; 443 444 pos = skb_push(skb, IEEE80211_CCMP_HDR_LEN); 445 memmove(pos, pos + IEEE80211_CCMP_HDR_LEN, hdrlen); 446 447 /* the HW only needs room for the IV, but not the actual IV */ 448 if (info->control.hw_key && 449 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) 450 return 0; 451 452 hdr = (struct ieee80211_hdr *) pos; 453 pos += hdrlen; 454 455 pn64 = atomic64_inc_return(&key->conf.tx_pn); 456 457 pn[5] = pn64; 458 pn[4] = pn64 >> 8; 459 pn[3] = pn64 >> 16; 460 pn[2] = pn64 >> 24; 461 pn[1] = pn64 >> 32; 462 pn[0] = pn64 >> 40; 463 464 ccmp_pn2hdr(pos, pn, key->conf.keyidx); 465 466 /* hwaccel - with software CCMP header */ 467 if (info->control.hw_key) 468 return 0; 469 470 pos += IEEE80211_CCMP_HDR_LEN; 471 ccmp_special_blocks(skb, pn, b_0, aad); 472 return ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, b_0, aad, pos, len, 473 skb_put(skb, mic_len)); 474 } 475 476 477 ieee80211_tx_result 478 ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx, 479 unsigned int mic_len) 480 { 481 struct sk_buff *skb; 482 483 ieee80211_tx_set_protected(tx); 484 485 skb_queue_walk(&tx->skbs, skb) { 486 if (ccmp_encrypt_skb(tx, skb, mic_len) < 0) 487 return TX_DROP; 488 } 489 490 return TX_CONTINUE; 491 } 492 493 494 ieee80211_rx_result 495 ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx, 496 unsigned int mic_len) 497 { 498 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 499 int hdrlen; 500 struct ieee80211_key *key = rx->key; 501 struct sk_buff *skb = rx->skb; 502 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 503 u8 pn[IEEE80211_CCMP_PN_LEN]; 504 int data_len; 505 int queue; 506 507 hdrlen = ieee80211_hdrlen(hdr->frame_control); 508 509 if (!ieee80211_is_data(hdr->frame_control) && 510 !ieee80211_is_robust_mgmt_frame(skb)) 511 return RX_CONTINUE; 512 513 if (status->flag & RX_FLAG_DECRYPTED) { 514 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_CCMP_HDR_LEN)) 515 return RX_DROP_UNUSABLE; 516 if (status->flag & RX_FLAG_MIC_STRIPPED) 517 mic_len = 0; 518 } else { 519 if (skb_linearize(rx->skb)) 520 return RX_DROP_UNUSABLE; 521 } 522 523 /* reload hdr - skb might have been reallocated */ 524 hdr = (void *)rx->skb->data; 525 526 data_len = skb->len - hdrlen - IEEE80211_CCMP_HDR_LEN - mic_len; 527 if (!rx->sta || data_len < 0) 528 return RX_DROP_UNUSABLE; 529 530 if (!(status->flag & RX_FLAG_PN_VALIDATED)) { 531 int res; 532 533 ccmp_hdr2pn(pn, skb->data + hdrlen); 534 535 queue = rx->security_idx; 536 537 res = memcmp(pn, key->u.ccmp.rx_pn[queue], 538 IEEE80211_CCMP_PN_LEN); 539 if (res < 0 || 540 (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) { 541 key->u.ccmp.replays++; 542 return RX_DROP_UNUSABLE; 543 } 544 545 if (!(status->flag & RX_FLAG_DECRYPTED)) { 546 u8 aad[2 * AES_BLOCK_SIZE]; 547 u8 b_0[AES_BLOCK_SIZE]; 548 /* hardware didn't decrypt/verify MIC */ 549 ccmp_special_blocks(skb, pn, b_0, aad); 550 551 if (ieee80211_aes_ccm_decrypt( 552 key->u.ccmp.tfm, b_0, aad, 553 skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN, 554 data_len, 555 skb->data + skb->len - mic_len)) 556 return RX_DROP_UNUSABLE; 557 } 558 559 memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN); 560 if (unlikely(ieee80211_is_frag(hdr))) 561 memcpy(rx->ccm_gcm.pn, pn, IEEE80211_CCMP_PN_LEN); 562 } 563 564 /* Remove CCMP header and MIC */ 565 if (pskb_trim(skb, skb->len - mic_len)) 566 return RX_DROP_UNUSABLE; 567 memmove(skb->data + IEEE80211_CCMP_HDR_LEN, skb->data, hdrlen); 568 skb_pull(skb, IEEE80211_CCMP_HDR_LEN); 569 570 return RX_CONTINUE; 571 } 572 573 static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad) 574 { 575 __le16 mask_fc; 576 u8 qos_tid; 577 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 578 579 memcpy(j_0, hdr->addr2, ETH_ALEN); 580 memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN); 581 j_0[13] = 0; 582 j_0[14] = 0; 583 j_0[AES_BLOCK_SIZE - 1] = 0x01; 584 585 /* AAD (extra authenticate-only data) / masked 802.11 header 586 * FC | A1 | A2 | A3 | SC | [A4] | [QC] 587 */ 588 put_unaligned_be16(ieee80211_hdrlen(hdr->frame_control) - 2, &aad[0]); 589 /* Mask FC: zero subtype b4 b5 b6 (if not mgmt) 590 * Retry, PwrMgt, MoreData; set Protected 591 */ 592 mask_fc = hdr->frame_control; 593 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | 594 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA); 595 if (!ieee80211_is_mgmt(hdr->frame_control)) 596 mask_fc &= ~cpu_to_le16(0x0070); 597 mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); 598 599 put_unaligned(mask_fc, (__le16 *)&aad[2]); 600 memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN); 601 602 /* Mask Seq#, leave Frag# */ 603 aad[22] = *((u8 *)&hdr->seq_ctrl) & 0x0f; 604 aad[23] = 0; 605 606 if (ieee80211_is_data_qos(hdr->frame_control)) 607 qos_tid = ieee80211_get_tid(hdr); 608 else 609 qos_tid = 0; 610 611 if (ieee80211_has_a4(hdr->frame_control)) { 612 memcpy(&aad[24], hdr->addr4, ETH_ALEN); 613 aad[30] = qos_tid; 614 aad[31] = 0; 615 } else { 616 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN); 617 aad[24] = qos_tid; 618 } 619 } 620 621 static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id) 622 { 623 hdr[0] = pn[5]; 624 hdr[1] = pn[4]; 625 hdr[2] = 0; 626 hdr[3] = 0x20 | (key_id << 6); 627 hdr[4] = pn[3]; 628 hdr[5] = pn[2]; 629 hdr[6] = pn[1]; 630 hdr[7] = pn[0]; 631 } 632 633 static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr) 634 { 635 pn[0] = hdr[7]; 636 pn[1] = hdr[6]; 637 pn[2] = hdr[5]; 638 pn[3] = hdr[4]; 639 pn[4] = hdr[1]; 640 pn[5] = hdr[0]; 641 } 642 643 static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) 644 { 645 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 646 struct ieee80211_key *key = tx->key; 647 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 648 int hdrlen, len, tail; 649 u8 *pos; 650 u8 pn[6]; 651 u64 pn64; 652 u8 aad[GCM_AAD_LEN]; 653 u8 j_0[AES_BLOCK_SIZE]; 654 655 if (info->control.hw_key && 656 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) && 657 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) && 658 !((info->control.hw_key->flags & 659 IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) && 660 ieee80211_is_mgmt(hdr->frame_control))) { 661 /* hwaccel has no need for preallocated room for GCMP 662 * header or MIC fields 663 */ 664 return 0; 665 } 666 667 hdrlen = ieee80211_hdrlen(hdr->frame_control); 668 len = skb->len - hdrlen; 669 670 if (info->control.hw_key) 671 tail = 0; 672 else 673 tail = IEEE80211_GCMP_MIC_LEN; 674 675 if (WARN_ON(skb_tailroom(skb) < tail || 676 skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN)) 677 return -1; 678 679 pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN); 680 memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen); 681 skb_set_network_header(skb, skb_network_offset(skb) + 682 IEEE80211_GCMP_HDR_LEN); 683 684 /* the HW only needs room for the IV, but not the actual IV */ 685 if (info->control.hw_key && 686 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) 687 return 0; 688 689 hdr = (struct ieee80211_hdr *)pos; 690 pos += hdrlen; 691 692 pn64 = atomic64_inc_return(&key->conf.tx_pn); 693 694 pn[5] = pn64; 695 pn[4] = pn64 >> 8; 696 pn[3] = pn64 >> 16; 697 pn[2] = pn64 >> 24; 698 pn[1] = pn64 >> 32; 699 pn[0] = pn64 >> 40; 700 701 gcmp_pn2hdr(pos, pn, key->conf.keyidx); 702 703 /* hwaccel - with software GCMP header */ 704 if (info->control.hw_key) 705 return 0; 706 707 pos += IEEE80211_GCMP_HDR_LEN; 708 gcmp_special_blocks(skb, pn, j_0, aad); 709 return ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len, 710 skb_put(skb, IEEE80211_GCMP_MIC_LEN)); 711 } 712 713 ieee80211_tx_result 714 ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx) 715 { 716 struct sk_buff *skb; 717 718 ieee80211_tx_set_protected(tx); 719 720 skb_queue_walk(&tx->skbs, skb) { 721 if (gcmp_encrypt_skb(tx, skb) < 0) 722 return TX_DROP; 723 } 724 725 return TX_CONTINUE; 726 } 727 728 ieee80211_rx_result 729 ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx) 730 { 731 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 732 int hdrlen; 733 struct ieee80211_key *key = rx->key; 734 struct sk_buff *skb = rx->skb; 735 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 736 u8 pn[IEEE80211_GCMP_PN_LEN]; 737 int data_len, queue, mic_len = IEEE80211_GCMP_MIC_LEN; 738 739 hdrlen = ieee80211_hdrlen(hdr->frame_control); 740 741 if (!ieee80211_is_data(hdr->frame_control) && 742 !ieee80211_is_robust_mgmt_frame(skb)) 743 return RX_CONTINUE; 744 745 if (status->flag & RX_FLAG_DECRYPTED) { 746 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN)) 747 return RX_DROP_UNUSABLE; 748 if (status->flag & RX_FLAG_MIC_STRIPPED) 749 mic_len = 0; 750 } else { 751 if (skb_linearize(rx->skb)) 752 return RX_DROP_UNUSABLE; 753 } 754 755 /* reload hdr - skb might have been reallocated */ 756 hdr = (void *)rx->skb->data; 757 758 data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN - mic_len; 759 if (!rx->sta || data_len < 0) 760 return RX_DROP_UNUSABLE; 761 762 if (!(status->flag & RX_FLAG_PN_VALIDATED)) { 763 int res; 764 765 gcmp_hdr2pn(pn, skb->data + hdrlen); 766 767 queue = rx->security_idx; 768 769 res = memcmp(pn, key->u.gcmp.rx_pn[queue], 770 IEEE80211_GCMP_PN_LEN); 771 if (res < 0 || 772 (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) { 773 key->u.gcmp.replays++; 774 return RX_DROP_UNUSABLE; 775 } 776 777 if (!(status->flag & RX_FLAG_DECRYPTED)) { 778 u8 aad[2 * AES_BLOCK_SIZE]; 779 u8 j_0[AES_BLOCK_SIZE]; 780 /* hardware didn't decrypt/verify MIC */ 781 gcmp_special_blocks(skb, pn, j_0, aad); 782 783 if (ieee80211_aes_gcm_decrypt( 784 key->u.gcmp.tfm, j_0, aad, 785 skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN, 786 data_len, 787 skb->data + skb->len - 788 IEEE80211_GCMP_MIC_LEN)) 789 return RX_DROP_UNUSABLE; 790 } 791 792 memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN); 793 if (unlikely(ieee80211_is_frag(hdr))) 794 memcpy(rx->ccm_gcm.pn, pn, IEEE80211_CCMP_PN_LEN); 795 } 796 797 /* Remove GCMP header and MIC */ 798 if (pskb_trim(skb, skb->len - mic_len)) 799 return RX_DROP_UNUSABLE; 800 memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen); 801 skb_pull(skb, IEEE80211_GCMP_HDR_LEN); 802 803 return RX_CONTINUE; 804 } 805 806 static ieee80211_tx_result 807 ieee80211_crypto_cs_encrypt(struct ieee80211_tx_data *tx, 808 struct sk_buff *skb) 809 { 810 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 811 struct ieee80211_key *key = tx->key; 812 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 813 int hdrlen; 814 u8 *pos, iv_len = key->conf.iv_len; 815 816 if (info->control.hw_key && 817 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) { 818 /* hwaccel has no need for preallocated head room */ 819 return TX_CONTINUE; 820 } 821 822 if (unlikely(skb_headroom(skb) < iv_len && 823 pskb_expand_head(skb, iv_len, 0, GFP_ATOMIC))) 824 return TX_DROP; 825 826 hdrlen = ieee80211_hdrlen(hdr->frame_control); 827 828 pos = skb_push(skb, iv_len); 829 memmove(pos, pos + iv_len, hdrlen); 830 831 return TX_CONTINUE; 832 } 833 834 static inline int ieee80211_crypto_cs_pn_compare(u8 *pn1, u8 *pn2, int len) 835 { 836 int i; 837 838 /* pn is little endian */ 839 for (i = len - 1; i >= 0; i--) { 840 if (pn1[i] < pn2[i]) 841 return -1; 842 else if (pn1[i] > pn2[i]) 843 return 1; 844 } 845 846 return 0; 847 } 848 849 static ieee80211_rx_result 850 ieee80211_crypto_cs_decrypt(struct ieee80211_rx_data *rx) 851 { 852 struct ieee80211_key *key = rx->key; 853 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 854 const struct ieee80211_cipher_scheme *cs = NULL; 855 int hdrlen = ieee80211_hdrlen(hdr->frame_control); 856 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 857 int data_len; 858 u8 *rx_pn; 859 u8 *skb_pn; 860 u8 qos_tid; 861 862 if (!rx->sta || !rx->sta->cipher_scheme || 863 !(status->flag & RX_FLAG_DECRYPTED)) 864 return RX_DROP_UNUSABLE; 865 866 if (!ieee80211_is_data(hdr->frame_control)) 867 return RX_CONTINUE; 868 869 cs = rx->sta->cipher_scheme; 870 871 data_len = rx->skb->len - hdrlen - cs->hdr_len; 872 873 if (data_len < 0) 874 return RX_DROP_UNUSABLE; 875 876 if (ieee80211_is_data_qos(hdr->frame_control)) 877 qos_tid = ieee80211_get_tid(hdr); 878 else 879 qos_tid = 0; 880 881 if (skb_linearize(rx->skb)) 882 return RX_DROP_UNUSABLE; 883 884 hdr = (struct ieee80211_hdr *)rx->skb->data; 885 886 rx_pn = key->u.gen.rx_pn[qos_tid]; 887 skb_pn = rx->skb->data + hdrlen + cs->pn_off; 888 889 if (ieee80211_crypto_cs_pn_compare(skb_pn, rx_pn, cs->pn_len) <= 0) 890 return RX_DROP_UNUSABLE; 891 892 memcpy(rx_pn, skb_pn, cs->pn_len); 893 894 /* remove security header and MIC */ 895 if (pskb_trim(rx->skb, rx->skb->len - cs->mic_len)) 896 return RX_DROP_UNUSABLE; 897 898 memmove(rx->skb->data + cs->hdr_len, rx->skb->data, hdrlen); 899 skb_pull(rx->skb, cs->hdr_len); 900 901 return RX_CONTINUE; 902 } 903 904 static void bip_aad(struct sk_buff *skb, u8 *aad) 905 { 906 __le16 mask_fc; 907 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 908 909 /* BIP AAD: FC(masked) || A1 || A2 || A3 */ 910 911 /* FC type/subtype */ 912 /* Mask FC Retry, PwrMgt, MoreData flags to zero */ 913 mask_fc = hdr->frame_control; 914 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM | 915 IEEE80211_FCTL_MOREDATA); 916 put_unaligned(mask_fc, (__le16 *) &aad[0]); 917 /* A1 || A2 || A3 */ 918 memcpy(aad + 2, &hdr->addr1, 3 * ETH_ALEN); 919 } 920 921 922 static inline void bip_ipn_set64(u8 *d, u64 pn) 923 { 924 *d++ = pn; 925 *d++ = pn >> 8; 926 *d++ = pn >> 16; 927 *d++ = pn >> 24; 928 *d++ = pn >> 32; 929 *d = pn >> 40; 930 } 931 932 static inline void bip_ipn_swap(u8 *d, const u8 *s) 933 { 934 *d++ = s[5]; 935 *d++ = s[4]; 936 *d++ = s[3]; 937 *d++ = s[2]; 938 *d++ = s[1]; 939 *d = s[0]; 940 } 941 942 943 ieee80211_tx_result 944 ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx) 945 { 946 struct sk_buff *skb; 947 struct ieee80211_tx_info *info; 948 struct ieee80211_key *key = tx->key; 949 struct ieee80211_mmie *mmie; 950 u8 aad[20]; 951 u64 pn64; 952 953 if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) 954 return TX_DROP; 955 956 skb = skb_peek(&tx->skbs); 957 958 info = IEEE80211_SKB_CB(skb); 959 960 if (info->control.hw_key && 961 !(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIE)) 962 return TX_CONTINUE; 963 964 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) 965 return TX_DROP; 966 967 mmie = skb_put(skb, sizeof(*mmie)); 968 mmie->element_id = WLAN_EID_MMIE; 969 mmie->length = sizeof(*mmie) - 2; 970 mmie->key_id = cpu_to_le16(key->conf.keyidx); 971 972 /* PN = PN + 1 */ 973 pn64 = atomic64_inc_return(&key->conf.tx_pn); 974 975 bip_ipn_set64(mmie->sequence_number, pn64); 976 977 if (info->control.hw_key) 978 return TX_CONTINUE; 979 980 bip_aad(skb, aad); 981 982 /* 983 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64) 984 */ 985 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad, 986 skb->data + 24, skb->len - 24, mmie->mic); 987 988 return TX_CONTINUE; 989 } 990 991 ieee80211_tx_result 992 ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx) 993 { 994 struct sk_buff *skb; 995 struct ieee80211_tx_info *info; 996 struct ieee80211_key *key = tx->key; 997 struct ieee80211_mmie_16 *mmie; 998 u8 aad[20]; 999 u64 pn64; 1000 1001 if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) 1002 return TX_DROP; 1003 1004 skb = skb_peek(&tx->skbs); 1005 1006 info = IEEE80211_SKB_CB(skb); 1007 1008 if (info->control.hw_key) 1009 return TX_CONTINUE; 1010 1011 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) 1012 return TX_DROP; 1013 1014 mmie = skb_put(skb, sizeof(*mmie)); 1015 mmie->element_id = WLAN_EID_MMIE; 1016 mmie->length = sizeof(*mmie) - 2; 1017 mmie->key_id = cpu_to_le16(key->conf.keyidx); 1018 1019 /* PN = PN + 1 */ 1020 pn64 = atomic64_inc_return(&key->conf.tx_pn); 1021 1022 bip_ipn_set64(mmie->sequence_number, pn64); 1023 1024 bip_aad(skb, aad); 1025 1026 /* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128) 1027 */ 1028 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad, 1029 skb->data + 24, skb->len - 24, mmie->mic); 1030 1031 return TX_CONTINUE; 1032 } 1033 1034 ieee80211_rx_result 1035 ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx) 1036 { 1037 struct sk_buff *skb = rx->skb; 1038 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1039 struct ieee80211_key *key = rx->key; 1040 struct ieee80211_mmie *mmie; 1041 u8 aad[20], mic[8], ipn[6]; 1042 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1043 1044 if (!ieee80211_is_mgmt(hdr->frame_control)) 1045 return RX_CONTINUE; 1046 1047 /* management frames are already linear */ 1048 1049 if (skb->len < 24 + sizeof(*mmie)) 1050 return RX_DROP_UNUSABLE; 1051 1052 mmie = (struct ieee80211_mmie *) 1053 (skb->data + skb->len - sizeof(*mmie)); 1054 if (mmie->element_id != WLAN_EID_MMIE || 1055 mmie->length != sizeof(*mmie) - 2) 1056 return RX_DROP_UNUSABLE; /* Invalid MMIE */ 1057 1058 bip_ipn_swap(ipn, mmie->sequence_number); 1059 1060 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) { 1061 key->u.aes_cmac.replays++; 1062 return RX_DROP_UNUSABLE; 1063 } 1064 1065 if (!(status->flag & RX_FLAG_DECRYPTED)) { 1066 /* hardware didn't decrypt/verify MIC */ 1067 bip_aad(skb, aad); 1068 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad, 1069 skb->data + 24, skb->len - 24, mic); 1070 if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) { 1071 key->u.aes_cmac.icverrors++; 1072 return RX_DROP_UNUSABLE; 1073 } 1074 } 1075 1076 memcpy(key->u.aes_cmac.rx_pn, ipn, 6); 1077 1078 /* Remove MMIE */ 1079 skb_trim(skb, skb->len - sizeof(*mmie)); 1080 1081 return RX_CONTINUE; 1082 } 1083 1084 ieee80211_rx_result 1085 ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx) 1086 { 1087 struct sk_buff *skb = rx->skb; 1088 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1089 struct ieee80211_key *key = rx->key; 1090 struct ieee80211_mmie_16 *mmie; 1091 u8 aad[20], mic[16], ipn[6]; 1092 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1093 1094 if (!ieee80211_is_mgmt(hdr->frame_control)) 1095 return RX_CONTINUE; 1096 1097 /* management frames are already linear */ 1098 1099 if (skb->len < 24 + sizeof(*mmie)) 1100 return RX_DROP_UNUSABLE; 1101 1102 mmie = (struct ieee80211_mmie_16 *) 1103 (skb->data + skb->len - sizeof(*mmie)); 1104 if (mmie->element_id != WLAN_EID_MMIE || 1105 mmie->length != sizeof(*mmie) - 2) 1106 return RX_DROP_UNUSABLE; /* Invalid MMIE */ 1107 1108 bip_ipn_swap(ipn, mmie->sequence_number); 1109 1110 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) { 1111 key->u.aes_cmac.replays++; 1112 return RX_DROP_UNUSABLE; 1113 } 1114 1115 if (!(status->flag & RX_FLAG_DECRYPTED)) { 1116 /* hardware didn't decrypt/verify MIC */ 1117 bip_aad(skb, aad); 1118 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad, 1119 skb->data + 24, skb->len - 24, mic); 1120 if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) { 1121 key->u.aes_cmac.icverrors++; 1122 return RX_DROP_UNUSABLE; 1123 } 1124 } 1125 1126 memcpy(key->u.aes_cmac.rx_pn, ipn, 6); 1127 1128 /* Remove MMIE */ 1129 skb_trim(skb, skb->len - sizeof(*mmie)); 1130 1131 return RX_CONTINUE; 1132 } 1133 1134 ieee80211_tx_result 1135 ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx) 1136 { 1137 struct sk_buff *skb; 1138 struct ieee80211_tx_info *info; 1139 struct ieee80211_key *key = tx->key; 1140 struct ieee80211_mmie_16 *mmie; 1141 struct ieee80211_hdr *hdr; 1142 u8 aad[GMAC_AAD_LEN]; 1143 u64 pn64; 1144 u8 nonce[GMAC_NONCE_LEN]; 1145 1146 if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) 1147 return TX_DROP; 1148 1149 skb = skb_peek(&tx->skbs); 1150 1151 info = IEEE80211_SKB_CB(skb); 1152 1153 if (info->control.hw_key) 1154 return TX_CONTINUE; 1155 1156 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) 1157 return TX_DROP; 1158 1159 mmie = skb_put(skb, sizeof(*mmie)); 1160 mmie->element_id = WLAN_EID_MMIE; 1161 mmie->length = sizeof(*mmie) - 2; 1162 mmie->key_id = cpu_to_le16(key->conf.keyidx); 1163 1164 /* PN = PN + 1 */ 1165 pn64 = atomic64_inc_return(&key->conf.tx_pn); 1166 1167 bip_ipn_set64(mmie->sequence_number, pn64); 1168 1169 bip_aad(skb, aad); 1170 1171 hdr = (struct ieee80211_hdr *)skb->data; 1172 memcpy(nonce, hdr->addr2, ETH_ALEN); 1173 bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number); 1174 1175 /* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */ 1176 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce, 1177 skb->data + 24, skb->len - 24, mmie->mic) < 0) 1178 return TX_DROP; 1179 1180 return TX_CONTINUE; 1181 } 1182 1183 ieee80211_rx_result 1184 ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx) 1185 { 1186 struct sk_buff *skb = rx->skb; 1187 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1188 struct ieee80211_key *key = rx->key; 1189 struct ieee80211_mmie_16 *mmie; 1190 u8 aad[GMAC_AAD_LEN], *mic, ipn[6], nonce[GMAC_NONCE_LEN]; 1191 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1192 1193 if (!ieee80211_is_mgmt(hdr->frame_control)) 1194 return RX_CONTINUE; 1195 1196 /* management frames are already linear */ 1197 1198 if (skb->len < 24 + sizeof(*mmie)) 1199 return RX_DROP_UNUSABLE; 1200 1201 mmie = (struct ieee80211_mmie_16 *) 1202 (skb->data + skb->len - sizeof(*mmie)); 1203 if (mmie->element_id != WLAN_EID_MMIE || 1204 mmie->length != sizeof(*mmie) - 2) 1205 return RX_DROP_UNUSABLE; /* Invalid MMIE */ 1206 1207 bip_ipn_swap(ipn, mmie->sequence_number); 1208 1209 if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) { 1210 key->u.aes_gmac.replays++; 1211 return RX_DROP_UNUSABLE; 1212 } 1213 1214 if (!(status->flag & RX_FLAG_DECRYPTED)) { 1215 /* hardware didn't decrypt/verify MIC */ 1216 bip_aad(skb, aad); 1217 1218 memcpy(nonce, hdr->addr2, ETH_ALEN); 1219 memcpy(nonce + ETH_ALEN, ipn, 6); 1220 1221 mic = kmalloc(GMAC_MIC_LEN, GFP_ATOMIC); 1222 if (!mic) 1223 return RX_DROP_UNUSABLE; 1224 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce, 1225 skb->data + 24, skb->len - 24, 1226 mic) < 0 || 1227 crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) { 1228 key->u.aes_gmac.icverrors++; 1229 kfree(mic); 1230 return RX_DROP_UNUSABLE; 1231 } 1232 kfree(mic); 1233 } 1234 1235 memcpy(key->u.aes_gmac.rx_pn, ipn, 6); 1236 1237 /* Remove MMIE */ 1238 skb_trim(skb, skb->len - sizeof(*mmie)); 1239 1240 return RX_CONTINUE; 1241 } 1242 1243 ieee80211_tx_result 1244 ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx) 1245 { 1246 struct sk_buff *skb; 1247 struct ieee80211_tx_info *info = NULL; 1248 ieee80211_tx_result res; 1249 1250 skb_queue_walk(&tx->skbs, skb) { 1251 info = IEEE80211_SKB_CB(skb); 1252 1253 /* handle hw-only algorithm */ 1254 if (!info->control.hw_key) 1255 return TX_DROP; 1256 1257 if (tx->key->flags & KEY_FLAG_CIPHER_SCHEME) { 1258 res = ieee80211_crypto_cs_encrypt(tx, skb); 1259 if (res != TX_CONTINUE) 1260 return res; 1261 } 1262 } 1263 1264 ieee80211_tx_set_protected(tx); 1265 1266 return TX_CONTINUE; 1267 } 1268 1269 ieee80211_rx_result 1270 ieee80211_crypto_hw_decrypt(struct ieee80211_rx_data *rx) 1271 { 1272 if (rx->sta && rx->sta->cipher_scheme) 1273 return ieee80211_crypto_cs_decrypt(rx); 1274 1275 return RX_DROP_UNUSABLE; 1276 } 1277