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 if (!(status->flag & RX_FLAG_ICV_STRIPPED)) 298 skb_trim(skb, skb->len - IEEE80211_TKIP_ICV_LEN); 299 300 /* Remove IV */ 301 memmove(skb->data + IEEE80211_TKIP_IV_LEN, skb->data, hdrlen); 302 skb_pull(skb, IEEE80211_TKIP_IV_LEN); 303 304 return RX_CONTINUE; 305 } 306 307 308 static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad) 309 { 310 __le16 mask_fc; 311 int a4_included, mgmt; 312 u8 qos_tid; 313 u16 len_a; 314 unsigned int hdrlen; 315 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 316 317 /* 318 * Mask FC: zero subtype b4 b5 b6 (if not mgmt) 319 * Retry, PwrMgt, MoreData; set Protected 320 */ 321 mgmt = ieee80211_is_mgmt(hdr->frame_control); 322 mask_fc = hdr->frame_control; 323 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | 324 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA); 325 if (!mgmt) 326 mask_fc &= ~cpu_to_le16(0x0070); 327 mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); 328 329 hdrlen = ieee80211_hdrlen(hdr->frame_control); 330 len_a = hdrlen - 2; 331 a4_included = ieee80211_has_a4(hdr->frame_control); 332 333 if (ieee80211_is_data_qos(hdr->frame_control)) 334 qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; 335 else 336 qos_tid = 0; 337 338 /* In CCM, the initial vectors (IV) used for CTR mode encryption and CBC 339 * mode authentication are not allowed to collide, yet both are derived 340 * from this vector b_0. We only set L := 1 here to indicate that the 341 * data size can be represented in (L+1) bytes. The CCM layer will take 342 * care of storing the data length in the top (L+1) bytes and setting 343 * and clearing the other bits as is required to derive the two IVs. 344 */ 345 b_0[0] = 0x1; 346 347 /* Nonce: Nonce Flags | A2 | PN 348 * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7) 349 */ 350 b_0[1] = qos_tid | (mgmt << 4); 351 memcpy(&b_0[2], hdr->addr2, ETH_ALEN); 352 memcpy(&b_0[8], pn, IEEE80211_CCMP_PN_LEN); 353 354 /* AAD (extra authenticate-only data) / masked 802.11 header 355 * FC | A1 | A2 | A3 | SC | [A4] | [QC] */ 356 put_unaligned_be16(len_a, &aad[0]); 357 put_unaligned(mask_fc, (__le16 *)&aad[2]); 358 memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN); 359 360 /* Mask Seq#, leave Frag# */ 361 aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f; 362 aad[23] = 0; 363 364 if (a4_included) { 365 memcpy(&aad[24], hdr->addr4, ETH_ALEN); 366 aad[30] = qos_tid; 367 aad[31] = 0; 368 } else { 369 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN); 370 aad[24] = qos_tid; 371 } 372 } 373 374 375 static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id) 376 { 377 hdr[0] = pn[5]; 378 hdr[1] = pn[4]; 379 hdr[2] = 0; 380 hdr[3] = 0x20 | (key_id << 6); 381 hdr[4] = pn[3]; 382 hdr[5] = pn[2]; 383 hdr[6] = pn[1]; 384 hdr[7] = pn[0]; 385 } 386 387 388 static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr) 389 { 390 pn[0] = hdr[7]; 391 pn[1] = hdr[6]; 392 pn[2] = hdr[5]; 393 pn[3] = hdr[4]; 394 pn[4] = hdr[1]; 395 pn[5] = hdr[0]; 396 } 397 398 399 static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb, 400 unsigned int mic_len) 401 { 402 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 403 struct ieee80211_key *key = tx->key; 404 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 405 int hdrlen, len, tail; 406 u8 *pos; 407 u8 pn[6]; 408 u64 pn64; 409 u8 aad[CCM_AAD_LEN]; 410 u8 b_0[AES_BLOCK_SIZE]; 411 412 if (info->control.hw_key && 413 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) && 414 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) && 415 !((info->control.hw_key->flags & 416 IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) && 417 ieee80211_is_mgmt(hdr->frame_control))) { 418 /* 419 * hwaccel has no need for preallocated room for CCMP 420 * header or MIC fields 421 */ 422 return 0; 423 } 424 425 hdrlen = ieee80211_hdrlen(hdr->frame_control); 426 len = skb->len - hdrlen; 427 428 if (info->control.hw_key) 429 tail = 0; 430 else 431 tail = mic_len; 432 433 if (WARN_ON(skb_tailroom(skb) < tail || 434 skb_headroom(skb) < IEEE80211_CCMP_HDR_LEN)) 435 return -1; 436 437 pos = skb_push(skb, IEEE80211_CCMP_HDR_LEN); 438 memmove(pos, pos + IEEE80211_CCMP_HDR_LEN, hdrlen); 439 440 /* the HW only needs room for the IV, but not the actual IV */ 441 if (info->control.hw_key && 442 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) 443 return 0; 444 445 hdr = (struct ieee80211_hdr *) pos; 446 pos += hdrlen; 447 448 pn64 = atomic64_inc_return(&key->conf.tx_pn); 449 450 pn[5] = pn64; 451 pn[4] = pn64 >> 8; 452 pn[3] = pn64 >> 16; 453 pn[2] = pn64 >> 24; 454 pn[1] = pn64 >> 32; 455 pn[0] = pn64 >> 40; 456 457 ccmp_pn2hdr(pos, pn, key->conf.keyidx); 458 459 /* hwaccel - with software CCMP header */ 460 if (info->control.hw_key) 461 return 0; 462 463 pos += IEEE80211_CCMP_HDR_LEN; 464 ccmp_special_blocks(skb, pn, b_0, aad); 465 return ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, b_0, aad, pos, len, 466 skb_put(skb, mic_len), mic_len); 467 } 468 469 470 ieee80211_tx_result 471 ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx, 472 unsigned int mic_len) 473 { 474 struct sk_buff *skb; 475 476 ieee80211_tx_set_protected(tx); 477 478 skb_queue_walk(&tx->skbs, skb) { 479 if (ccmp_encrypt_skb(tx, skb, mic_len) < 0) 480 return TX_DROP; 481 } 482 483 return TX_CONTINUE; 484 } 485 486 487 ieee80211_rx_result 488 ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx, 489 unsigned int mic_len) 490 { 491 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 492 int hdrlen; 493 struct ieee80211_key *key = rx->key; 494 struct sk_buff *skb = rx->skb; 495 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 496 u8 pn[IEEE80211_CCMP_PN_LEN]; 497 int data_len; 498 int queue; 499 500 hdrlen = ieee80211_hdrlen(hdr->frame_control); 501 502 if (!ieee80211_is_data(hdr->frame_control) && 503 !ieee80211_is_robust_mgmt_frame(skb)) 504 return RX_CONTINUE; 505 506 if (status->flag & RX_FLAG_DECRYPTED) { 507 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_CCMP_HDR_LEN)) 508 return RX_DROP_UNUSABLE; 509 if (status->flag & RX_FLAG_MIC_STRIPPED) 510 mic_len = 0; 511 } else { 512 if (skb_linearize(rx->skb)) 513 return RX_DROP_UNUSABLE; 514 } 515 516 data_len = skb->len - hdrlen - IEEE80211_CCMP_HDR_LEN - mic_len; 517 if (!rx->sta || data_len < 0) 518 return RX_DROP_UNUSABLE; 519 520 if (!(status->flag & RX_FLAG_PN_VALIDATED)) { 521 int res; 522 523 ccmp_hdr2pn(pn, skb->data + hdrlen); 524 525 queue = rx->security_idx; 526 527 res = memcmp(pn, key->u.ccmp.rx_pn[queue], 528 IEEE80211_CCMP_PN_LEN); 529 if (res < 0 || 530 (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) { 531 key->u.ccmp.replays++; 532 return RX_DROP_UNUSABLE; 533 } 534 535 if (!(status->flag & RX_FLAG_DECRYPTED)) { 536 u8 aad[2 * AES_BLOCK_SIZE]; 537 u8 b_0[AES_BLOCK_SIZE]; 538 /* hardware didn't decrypt/verify MIC */ 539 ccmp_special_blocks(skb, pn, b_0, aad); 540 541 if (ieee80211_aes_ccm_decrypt( 542 key->u.ccmp.tfm, b_0, aad, 543 skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN, 544 data_len, 545 skb->data + skb->len - mic_len, mic_len)) 546 return RX_DROP_UNUSABLE; 547 } 548 549 memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN); 550 } 551 552 /* Remove CCMP header and MIC */ 553 if (pskb_trim(skb, skb->len - mic_len)) 554 return RX_DROP_UNUSABLE; 555 memmove(skb->data + IEEE80211_CCMP_HDR_LEN, skb->data, hdrlen); 556 skb_pull(skb, IEEE80211_CCMP_HDR_LEN); 557 558 return RX_CONTINUE; 559 } 560 561 static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad) 562 { 563 __le16 mask_fc; 564 u8 qos_tid; 565 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 566 567 memcpy(j_0, hdr->addr2, ETH_ALEN); 568 memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN); 569 j_0[13] = 0; 570 j_0[14] = 0; 571 j_0[AES_BLOCK_SIZE - 1] = 0x01; 572 573 /* AAD (extra authenticate-only data) / masked 802.11 header 574 * FC | A1 | A2 | A3 | SC | [A4] | [QC] 575 */ 576 put_unaligned_be16(ieee80211_hdrlen(hdr->frame_control) - 2, &aad[0]); 577 /* Mask FC: zero subtype b4 b5 b6 (if not mgmt) 578 * Retry, PwrMgt, MoreData; set Protected 579 */ 580 mask_fc = hdr->frame_control; 581 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | 582 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA); 583 if (!ieee80211_is_mgmt(hdr->frame_control)) 584 mask_fc &= ~cpu_to_le16(0x0070); 585 mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); 586 587 put_unaligned(mask_fc, (__le16 *)&aad[2]); 588 memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN); 589 590 /* Mask Seq#, leave Frag# */ 591 aad[22] = *((u8 *)&hdr->seq_ctrl) & 0x0f; 592 aad[23] = 0; 593 594 if (ieee80211_is_data_qos(hdr->frame_control)) 595 qos_tid = *ieee80211_get_qos_ctl(hdr) & 596 IEEE80211_QOS_CTL_TID_MASK; 597 else 598 qos_tid = 0; 599 600 if (ieee80211_has_a4(hdr->frame_control)) { 601 memcpy(&aad[24], hdr->addr4, ETH_ALEN); 602 aad[30] = qos_tid; 603 aad[31] = 0; 604 } else { 605 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN); 606 aad[24] = qos_tid; 607 } 608 } 609 610 static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id) 611 { 612 hdr[0] = pn[5]; 613 hdr[1] = pn[4]; 614 hdr[2] = 0; 615 hdr[3] = 0x20 | (key_id << 6); 616 hdr[4] = pn[3]; 617 hdr[5] = pn[2]; 618 hdr[6] = pn[1]; 619 hdr[7] = pn[0]; 620 } 621 622 static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr) 623 { 624 pn[0] = hdr[7]; 625 pn[1] = hdr[6]; 626 pn[2] = hdr[5]; 627 pn[3] = hdr[4]; 628 pn[4] = hdr[1]; 629 pn[5] = hdr[0]; 630 } 631 632 static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) 633 { 634 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 635 struct ieee80211_key *key = tx->key; 636 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 637 int hdrlen, len, tail; 638 u8 *pos; 639 u8 pn[6]; 640 u64 pn64; 641 u8 aad[GCM_AAD_LEN]; 642 u8 j_0[AES_BLOCK_SIZE]; 643 644 if (info->control.hw_key && 645 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) && 646 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) && 647 !((info->control.hw_key->flags & 648 IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) && 649 ieee80211_is_mgmt(hdr->frame_control))) { 650 /* hwaccel has no need for preallocated room for GCMP 651 * header or MIC fields 652 */ 653 return 0; 654 } 655 656 hdrlen = ieee80211_hdrlen(hdr->frame_control); 657 len = skb->len - hdrlen; 658 659 if (info->control.hw_key) 660 tail = 0; 661 else 662 tail = IEEE80211_GCMP_MIC_LEN; 663 664 if (WARN_ON(skb_tailroom(skb) < tail || 665 skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN)) 666 return -1; 667 668 pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN); 669 memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen); 670 skb_set_network_header(skb, skb_network_offset(skb) + 671 IEEE80211_GCMP_HDR_LEN); 672 673 /* the HW only needs room for the IV, but not the actual IV */ 674 if (info->control.hw_key && 675 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) 676 return 0; 677 678 hdr = (struct ieee80211_hdr *)pos; 679 pos += hdrlen; 680 681 pn64 = atomic64_inc_return(&key->conf.tx_pn); 682 683 pn[5] = pn64; 684 pn[4] = pn64 >> 8; 685 pn[3] = pn64 >> 16; 686 pn[2] = pn64 >> 24; 687 pn[1] = pn64 >> 32; 688 pn[0] = pn64 >> 40; 689 690 gcmp_pn2hdr(pos, pn, key->conf.keyidx); 691 692 /* hwaccel - with software GCMP header */ 693 if (info->control.hw_key) 694 return 0; 695 696 pos += IEEE80211_GCMP_HDR_LEN; 697 gcmp_special_blocks(skb, pn, j_0, aad); 698 return ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len, 699 skb_put(skb, IEEE80211_GCMP_MIC_LEN)); 700 } 701 702 ieee80211_tx_result 703 ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx) 704 { 705 struct sk_buff *skb; 706 707 ieee80211_tx_set_protected(tx); 708 709 skb_queue_walk(&tx->skbs, skb) { 710 if (gcmp_encrypt_skb(tx, skb) < 0) 711 return TX_DROP; 712 } 713 714 return TX_CONTINUE; 715 } 716 717 ieee80211_rx_result 718 ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx) 719 { 720 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 721 int hdrlen; 722 struct ieee80211_key *key = rx->key; 723 struct sk_buff *skb = rx->skb; 724 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 725 u8 pn[IEEE80211_GCMP_PN_LEN]; 726 int data_len, queue, mic_len = IEEE80211_GCMP_MIC_LEN; 727 728 hdrlen = ieee80211_hdrlen(hdr->frame_control); 729 730 if (!ieee80211_is_data(hdr->frame_control) && 731 !ieee80211_is_robust_mgmt_frame(skb)) 732 return RX_CONTINUE; 733 734 if (status->flag & RX_FLAG_DECRYPTED) { 735 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN)) 736 return RX_DROP_UNUSABLE; 737 if (status->flag & RX_FLAG_MIC_STRIPPED) 738 mic_len = 0; 739 } else { 740 if (skb_linearize(rx->skb)) 741 return RX_DROP_UNUSABLE; 742 } 743 744 data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN - mic_len; 745 if (!rx->sta || data_len < 0) 746 return RX_DROP_UNUSABLE; 747 748 if (!(status->flag & RX_FLAG_PN_VALIDATED)) { 749 int res; 750 751 gcmp_hdr2pn(pn, skb->data + hdrlen); 752 753 queue = rx->security_idx; 754 755 res = memcmp(pn, key->u.gcmp.rx_pn[queue], 756 IEEE80211_GCMP_PN_LEN); 757 if (res < 0 || 758 (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) { 759 key->u.gcmp.replays++; 760 return RX_DROP_UNUSABLE; 761 } 762 763 if (!(status->flag & RX_FLAG_DECRYPTED)) { 764 u8 aad[2 * AES_BLOCK_SIZE]; 765 u8 j_0[AES_BLOCK_SIZE]; 766 /* hardware didn't decrypt/verify MIC */ 767 gcmp_special_blocks(skb, pn, j_0, aad); 768 769 if (ieee80211_aes_gcm_decrypt( 770 key->u.gcmp.tfm, j_0, aad, 771 skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN, 772 data_len, 773 skb->data + skb->len - 774 IEEE80211_GCMP_MIC_LEN)) 775 return RX_DROP_UNUSABLE; 776 } 777 778 memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN); 779 } 780 781 /* Remove GCMP header and MIC */ 782 if (pskb_trim(skb, skb->len - mic_len)) 783 return RX_DROP_UNUSABLE; 784 memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen); 785 skb_pull(skb, IEEE80211_GCMP_HDR_LEN); 786 787 return RX_CONTINUE; 788 } 789 790 static ieee80211_tx_result 791 ieee80211_crypto_cs_encrypt(struct ieee80211_tx_data *tx, 792 struct sk_buff *skb) 793 { 794 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 795 struct ieee80211_key *key = tx->key; 796 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 797 int hdrlen; 798 u8 *pos, iv_len = key->conf.iv_len; 799 800 if (info->control.hw_key && 801 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) { 802 /* hwaccel has no need for preallocated head room */ 803 return TX_CONTINUE; 804 } 805 806 if (unlikely(skb_headroom(skb) < iv_len && 807 pskb_expand_head(skb, iv_len, 0, GFP_ATOMIC))) 808 return TX_DROP; 809 810 hdrlen = ieee80211_hdrlen(hdr->frame_control); 811 812 pos = skb_push(skb, iv_len); 813 memmove(pos, pos + iv_len, hdrlen); 814 815 return TX_CONTINUE; 816 } 817 818 static inline int ieee80211_crypto_cs_pn_compare(u8 *pn1, u8 *pn2, int len) 819 { 820 int i; 821 822 /* pn is little endian */ 823 for (i = len - 1; i >= 0; i--) { 824 if (pn1[i] < pn2[i]) 825 return -1; 826 else if (pn1[i] > pn2[i]) 827 return 1; 828 } 829 830 return 0; 831 } 832 833 static ieee80211_rx_result 834 ieee80211_crypto_cs_decrypt(struct ieee80211_rx_data *rx) 835 { 836 struct ieee80211_key *key = rx->key; 837 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 838 const struct ieee80211_cipher_scheme *cs = NULL; 839 int hdrlen = ieee80211_hdrlen(hdr->frame_control); 840 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb); 841 int data_len; 842 u8 *rx_pn; 843 u8 *skb_pn; 844 u8 qos_tid; 845 846 if (!rx->sta || !rx->sta->cipher_scheme || 847 !(status->flag & RX_FLAG_DECRYPTED)) 848 return RX_DROP_UNUSABLE; 849 850 if (!ieee80211_is_data(hdr->frame_control)) 851 return RX_CONTINUE; 852 853 cs = rx->sta->cipher_scheme; 854 855 data_len = rx->skb->len - hdrlen - cs->hdr_len; 856 857 if (data_len < 0) 858 return RX_DROP_UNUSABLE; 859 860 if (ieee80211_is_data_qos(hdr->frame_control)) 861 qos_tid = *ieee80211_get_qos_ctl(hdr) & 862 IEEE80211_QOS_CTL_TID_MASK; 863 else 864 qos_tid = 0; 865 866 if (skb_linearize(rx->skb)) 867 return RX_DROP_UNUSABLE; 868 869 hdr = (struct ieee80211_hdr *)rx->skb->data; 870 871 rx_pn = key->u.gen.rx_pn[qos_tid]; 872 skb_pn = rx->skb->data + hdrlen + cs->pn_off; 873 874 if (ieee80211_crypto_cs_pn_compare(skb_pn, rx_pn, cs->pn_len) <= 0) 875 return RX_DROP_UNUSABLE; 876 877 memcpy(rx_pn, skb_pn, cs->pn_len); 878 879 /* remove security header and MIC */ 880 if (pskb_trim(rx->skb, rx->skb->len - cs->mic_len)) 881 return RX_DROP_UNUSABLE; 882 883 memmove(rx->skb->data + cs->hdr_len, rx->skb->data, hdrlen); 884 skb_pull(rx->skb, cs->hdr_len); 885 886 return RX_CONTINUE; 887 } 888 889 static void bip_aad(struct sk_buff *skb, u8 *aad) 890 { 891 __le16 mask_fc; 892 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 893 894 /* BIP AAD: FC(masked) || A1 || A2 || A3 */ 895 896 /* FC type/subtype */ 897 /* Mask FC Retry, PwrMgt, MoreData flags to zero */ 898 mask_fc = hdr->frame_control; 899 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM | 900 IEEE80211_FCTL_MOREDATA); 901 put_unaligned(mask_fc, (__le16 *) &aad[0]); 902 /* A1 || A2 || A3 */ 903 memcpy(aad + 2, &hdr->addr1, 3 * ETH_ALEN); 904 } 905 906 907 static inline void bip_ipn_set64(u8 *d, u64 pn) 908 { 909 *d++ = pn; 910 *d++ = pn >> 8; 911 *d++ = pn >> 16; 912 *d++ = pn >> 24; 913 *d++ = pn >> 32; 914 *d = pn >> 40; 915 } 916 917 static inline void bip_ipn_swap(u8 *d, const u8 *s) 918 { 919 *d++ = s[5]; 920 *d++ = s[4]; 921 *d++ = s[3]; 922 *d++ = s[2]; 923 *d++ = s[1]; 924 *d = s[0]; 925 } 926 927 928 ieee80211_tx_result 929 ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx) 930 { 931 struct sk_buff *skb; 932 struct ieee80211_tx_info *info; 933 struct ieee80211_key *key = tx->key; 934 struct ieee80211_mmie *mmie; 935 u8 aad[20]; 936 u64 pn64; 937 938 if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) 939 return TX_DROP; 940 941 skb = skb_peek(&tx->skbs); 942 943 info = IEEE80211_SKB_CB(skb); 944 945 if (info->control.hw_key) 946 return TX_CONTINUE; 947 948 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) 949 return TX_DROP; 950 951 mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie)); 952 mmie->element_id = WLAN_EID_MMIE; 953 mmie->length = sizeof(*mmie) - 2; 954 mmie->key_id = cpu_to_le16(key->conf.keyidx); 955 956 /* PN = PN + 1 */ 957 pn64 = atomic64_inc_return(&key->conf.tx_pn); 958 959 bip_ipn_set64(mmie->sequence_number, pn64); 960 961 bip_aad(skb, aad); 962 963 /* 964 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64) 965 */ 966 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad, 967 skb->data + 24, skb->len - 24, mmie->mic); 968 969 return TX_CONTINUE; 970 } 971 972 ieee80211_tx_result 973 ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx) 974 { 975 struct sk_buff *skb; 976 struct ieee80211_tx_info *info; 977 struct ieee80211_key *key = tx->key; 978 struct ieee80211_mmie_16 *mmie; 979 u8 aad[20]; 980 u64 pn64; 981 982 if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) 983 return TX_DROP; 984 985 skb = skb_peek(&tx->skbs); 986 987 info = IEEE80211_SKB_CB(skb); 988 989 if (info->control.hw_key) 990 return TX_CONTINUE; 991 992 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) 993 return TX_DROP; 994 995 mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie)); 996 mmie->element_id = WLAN_EID_MMIE; 997 mmie->length = sizeof(*mmie) - 2; 998 mmie->key_id = cpu_to_le16(key->conf.keyidx); 999 1000 /* PN = PN + 1 */ 1001 pn64 = atomic64_inc_return(&key->conf.tx_pn); 1002 1003 bip_ipn_set64(mmie->sequence_number, pn64); 1004 1005 bip_aad(skb, aad); 1006 1007 /* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128) 1008 */ 1009 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad, 1010 skb->data + 24, skb->len - 24, mmie->mic); 1011 1012 return TX_CONTINUE; 1013 } 1014 1015 ieee80211_rx_result 1016 ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx) 1017 { 1018 struct sk_buff *skb = rx->skb; 1019 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1020 struct ieee80211_key *key = rx->key; 1021 struct ieee80211_mmie *mmie; 1022 u8 aad[20], mic[8], ipn[6]; 1023 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1024 1025 if (!ieee80211_is_mgmt(hdr->frame_control)) 1026 return RX_CONTINUE; 1027 1028 /* management frames are already linear */ 1029 1030 if (skb->len < 24 + sizeof(*mmie)) 1031 return RX_DROP_UNUSABLE; 1032 1033 mmie = (struct ieee80211_mmie *) 1034 (skb->data + skb->len - sizeof(*mmie)); 1035 if (mmie->element_id != WLAN_EID_MMIE || 1036 mmie->length != sizeof(*mmie) - 2) 1037 return RX_DROP_UNUSABLE; /* Invalid MMIE */ 1038 1039 bip_ipn_swap(ipn, mmie->sequence_number); 1040 1041 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) { 1042 key->u.aes_cmac.replays++; 1043 return RX_DROP_UNUSABLE; 1044 } 1045 1046 if (!(status->flag & RX_FLAG_DECRYPTED)) { 1047 /* hardware didn't decrypt/verify MIC */ 1048 bip_aad(skb, aad); 1049 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad, 1050 skb->data + 24, skb->len - 24, mic); 1051 if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) { 1052 key->u.aes_cmac.icverrors++; 1053 return RX_DROP_UNUSABLE; 1054 } 1055 } 1056 1057 memcpy(key->u.aes_cmac.rx_pn, ipn, 6); 1058 1059 /* Remove MMIE */ 1060 skb_trim(skb, skb->len - sizeof(*mmie)); 1061 1062 return RX_CONTINUE; 1063 } 1064 1065 ieee80211_rx_result 1066 ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx) 1067 { 1068 struct sk_buff *skb = rx->skb; 1069 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1070 struct ieee80211_key *key = rx->key; 1071 struct ieee80211_mmie_16 *mmie; 1072 u8 aad[20], mic[16], ipn[6]; 1073 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1074 1075 if (!ieee80211_is_mgmt(hdr->frame_control)) 1076 return RX_CONTINUE; 1077 1078 /* management frames are already linear */ 1079 1080 if (skb->len < 24 + sizeof(*mmie)) 1081 return RX_DROP_UNUSABLE; 1082 1083 mmie = (struct ieee80211_mmie_16 *) 1084 (skb->data + skb->len - sizeof(*mmie)); 1085 if (mmie->element_id != WLAN_EID_MMIE || 1086 mmie->length != sizeof(*mmie) - 2) 1087 return RX_DROP_UNUSABLE; /* Invalid MMIE */ 1088 1089 bip_ipn_swap(ipn, mmie->sequence_number); 1090 1091 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) { 1092 key->u.aes_cmac.replays++; 1093 return RX_DROP_UNUSABLE; 1094 } 1095 1096 if (!(status->flag & RX_FLAG_DECRYPTED)) { 1097 /* hardware didn't decrypt/verify MIC */ 1098 bip_aad(skb, aad); 1099 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad, 1100 skb->data + 24, skb->len - 24, mic); 1101 if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) { 1102 key->u.aes_cmac.icverrors++; 1103 return RX_DROP_UNUSABLE; 1104 } 1105 } 1106 1107 memcpy(key->u.aes_cmac.rx_pn, ipn, 6); 1108 1109 /* Remove MMIE */ 1110 skb_trim(skb, skb->len - sizeof(*mmie)); 1111 1112 return RX_CONTINUE; 1113 } 1114 1115 ieee80211_tx_result 1116 ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx) 1117 { 1118 struct sk_buff *skb; 1119 struct ieee80211_tx_info *info; 1120 struct ieee80211_key *key = tx->key; 1121 struct ieee80211_mmie_16 *mmie; 1122 struct ieee80211_hdr *hdr; 1123 u8 aad[GMAC_AAD_LEN]; 1124 u64 pn64; 1125 u8 nonce[GMAC_NONCE_LEN]; 1126 1127 if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) 1128 return TX_DROP; 1129 1130 skb = skb_peek(&tx->skbs); 1131 1132 info = IEEE80211_SKB_CB(skb); 1133 1134 if (info->control.hw_key) 1135 return TX_CONTINUE; 1136 1137 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) 1138 return TX_DROP; 1139 1140 mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie)); 1141 mmie->element_id = WLAN_EID_MMIE; 1142 mmie->length = sizeof(*mmie) - 2; 1143 mmie->key_id = cpu_to_le16(key->conf.keyidx); 1144 1145 /* PN = PN + 1 */ 1146 pn64 = atomic64_inc_return(&key->conf.tx_pn); 1147 1148 bip_ipn_set64(mmie->sequence_number, pn64); 1149 1150 bip_aad(skb, aad); 1151 1152 hdr = (struct ieee80211_hdr *)skb->data; 1153 memcpy(nonce, hdr->addr2, ETH_ALEN); 1154 bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number); 1155 1156 /* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */ 1157 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce, 1158 skb->data + 24, skb->len - 24, mmie->mic) < 0) 1159 return TX_DROP; 1160 1161 return TX_CONTINUE; 1162 } 1163 1164 ieee80211_rx_result 1165 ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx) 1166 { 1167 struct sk_buff *skb = rx->skb; 1168 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1169 struct ieee80211_key *key = rx->key; 1170 struct ieee80211_mmie_16 *mmie; 1171 u8 aad[GMAC_AAD_LEN], mic[GMAC_MIC_LEN], ipn[6], nonce[GMAC_NONCE_LEN]; 1172 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1173 1174 if (!ieee80211_is_mgmt(hdr->frame_control)) 1175 return RX_CONTINUE; 1176 1177 /* management frames are already linear */ 1178 1179 if (skb->len < 24 + sizeof(*mmie)) 1180 return RX_DROP_UNUSABLE; 1181 1182 mmie = (struct ieee80211_mmie_16 *) 1183 (skb->data + skb->len - sizeof(*mmie)); 1184 if (mmie->element_id != WLAN_EID_MMIE || 1185 mmie->length != sizeof(*mmie) - 2) 1186 return RX_DROP_UNUSABLE; /* Invalid MMIE */ 1187 1188 bip_ipn_swap(ipn, mmie->sequence_number); 1189 1190 if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) { 1191 key->u.aes_gmac.replays++; 1192 return RX_DROP_UNUSABLE; 1193 } 1194 1195 if (!(status->flag & RX_FLAG_DECRYPTED)) { 1196 /* hardware didn't decrypt/verify MIC */ 1197 bip_aad(skb, aad); 1198 1199 memcpy(nonce, hdr->addr2, ETH_ALEN); 1200 memcpy(nonce + ETH_ALEN, ipn, 6); 1201 1202 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce, 1203 skb->data + 24, skb->len - 24, 1204 mic) < 0 || 1205 memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) { 1206 key->u.aes_gmac.icverrors++; 1207 return RX_DROP_UNUSABLE; 1208 } 1209 } 1210 1211 memcpy(key->u.aes_gmac.rx_pn, ipn, 6); 1212 1213 /* Remove MMIE */ 1214 skb_trim(skb, skb->len - sizeof(*mmie)); 1215 1216 return RX_CONTINUE; 1217 } 1218 1219 ieee80211_tx_result 1220 ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx) 1221 { 1222 struct sk_buff *skb; 1223 struct ieee80211_tx_info *info = NULL; 1224 ieee80211_tx_result res; 1225 1226 skb_queue_walk(&tx->skbs, skb) { 1227 info = IEEE80211_SKB_CB(skb); 1228 1229 /* handle hw-only algorithm */ 1230 if (!info->control.hw_key) 1231 return TX_DROP; 1232 1233 if (tx->key->flags & KEY_FLAG_CIPHER_SCHEME) { 1234 res = ieee80211_crypto_cs_encrypt(tx, skb); 1235 if (res != TX_CONTINUE) 1236 return res; 1237 } 1238 } 1239 1240 ieee80211_tx_set_protected(tx); 1241 1242 return TX_CONTINUE; 1243 } 1244 1245 ieee80211_rx_result 1246 ieee80211_crypto_hw_decrypt(struct ieee80211_rx_data *rx) 1247 { 1248 if (rx->sta && rx->sta->cipher_scheme) 1249 return ieee80211_crypto_cs_decrypt(rx); 1250 1251 return RX_DROP_UNUSABLE; 1252 } 1253