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) 2020-2023 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 <linux/unaligned.h> 16 #include <net/mac80211.h> 17 #include <crypto/aes.h> 18 #include <crypto/utils.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_U_AP_RX_GROUPCAST; 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_U_SHORT_MMIC; 154 155 if (skb_linearize(rx->skb)) 156 return RX_DROP_U_OOM; 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_U_MMIC_FAIL; 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_U_SHORT_TKIP; 280 281 /* it may be possible to optimize this a bit more */ 282 if (skb_linearize(rx->skb)) 283 return RX_DROP_U_OOM; 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_U_TKIP_FAIL; 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 * Calculate AAD for CCMP/GCMP, returning qos_tid since we 316 * need that in CCMP also for b_0. 317 */ 318 static u8 ccmp_gcmp_aad(struct sk_buff *skb, u8 *aad, bool spp_amsdu) 319 { 320 struct ieee80211_hdr *hdr = (void *)skb->data; 321 __le16 mask_fc; 322 int a4_included, mgmt; 323 u8 qos_tid; 324 u16 len_a = 22; 325 326 /* 327 * Mask FC: zero subtype b4 b5 b6 (if not mgmt) 328 * Retry, PwrMgt, MoreData, Order (if Qos Data); set Protected 329 */ 330 mgmt = ieee80211_is_mgmt(hdr->frame_control); 331 mask_fc = hdr->frame_control; 332 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | 333 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA); 334 if (!mgmt) 335 mask_fc &= ~cpu_to_le16(0x0070); 336 mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); 337 338 a4_included = ieee80211_has_a4(hdr->frame_control); 339 if (a4_included) 340 len_a += 6; 341 342 if (ieee80211_is_data_qos(hdr->frame_control)) { 343 qos_tid = *ieee80211_get_qos_ctl(hdr); 344 345 if (spp_amsdu) 346 qos_tid &= IEEE80211_QOS_CTL_TID_MASK | 347 IEEE80211_QOS_CTL_A_MSDU_PRESENT; 348 else 349 qos_tid &= IEEE80211_QOS_CTL_TID_MASK; 350 351 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_ORDER); 352 len_a += 2; 353 } else { 354 qos_tid = 0; 355 } 356 357 /* AAD (extra authenticate-only data) / masked 802.11 header 358 * FC | A1 | A2 | A3 | SC | [A4] | [QC] */ 359 put_unaligned_be16(len_a, &aad[0]); 360 put_unaligned(mask_fc, (__le16 *)&aad[2]); 361 memcpy(&aad[4], &hdr->addrs, 3 * ETH_ALEN); 362 363 /* Mask Seq#, leave Frag# */ 364 aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f; 365 aad[23] = 0; 366 367 if (a4_included) { 368 memcpy(&aad[24], hdr->addr4, ETH_ALEN); 369 aad[30] = qos_tid; 370 aad[31] = 0; 371 } else { 372 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN); 373 aad[24] = qos_tid; 374 } 375 376 return qos_tid; 377 } 378 379 static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad, 380 bool spp_amsdu) 381 { 382 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 383 u8 qos_tid = ccmp_gcmp_aad(skb, aad, spp_amsdu); 384 385 /* In CCM, the initial vectors (IV) used for CTR mode encryption and CBC 386 * mode authentication are not allowed to collide, yet both are derived 387 * from this vector b_0. We only set L := 1 here to indicate that the 388 * data size can be represented in (L+1) bytes. The CCM layer will take 389 * care of storing the data length in the top (L+1) bytes and setting 390 * and clearing the other bits as is required to derive the two IVs. 391 */ 392 b_0[0] = 0x1; 393 394 /* Nonce: Nonce Flags | A2 | PN 395 * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7) 396 */ 397 b_0[1] = qos_tid | (ieee80211_is_mgmt(hdr->frame_control) << 4); 398 memcpy(&b_0[2], hdr->addr2, ETH_ALEN); 399 memcpy(&b_0[8], pn, IEEE80211_CCMP_PN_LEN); 400 } 401 402 static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id) 403 { 404 hdr[0] = pn[5]; 405 hdr[1] = pn[4]; 406 hdr[2] = 0; 407 hdr[3] = 0x20 | (key_id << 6); 408 hdr[4] = pn[3]; 409 hdr[5] = pn[2]; 410 hdr[6] = pn[1]; 411 hdr[7] = pn[0]; 412 } 413 414 415 static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr) 416 { 417 pn[0] = hdr[7]; 418 pn[1] = hdr[6]; 419 pn[2] = hdr[5]; 420 pn[3] = hdr[4]; 421 pn[4] = hdr[1]; 422 pn[5] = hdr[0]; 423 } 424 425 426 static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb, 427 unsigned int mic_len) 428 { 429 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 430 struct ieee80211_key *key = tx->key; 431 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 432 int hdrlen, len, tail; 433 u8 *pos; 434 u8 pn[6]; 435 u64 pn64; 436 u8 aad[CCM_AAD_LEN]; 437 u8 b_0[AES_BLOCK_SIZE]; 438 439 if (info->control.hw_key && 440 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) && 441 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) && 442 !((info->control.hw_key->flags & 443 IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) && 444 ieee80211_is_mgmt(hdr->frame_control))) { 445 /* 446 * hwaccel has no need for preallocated room for CCMP 447 * header or MIC fields 448 */ 449 return 0; 450 } 451 452 hdrlen = ieee80211_hdrlen(hdr->frame_control); 453 len = skb->len - hdrlen; 454 455 if (info->control.hw_key) 456 tail = 0; 457 else 458 tail = mic_len; 459 460 if (WARN_ON(skb_tailroom(skb) < tail || 461 skb_headroom(skb) < IEEE80211_CCMP_HDR_LEN)) 462 return -1; 463 464 pos = skb_push(skb, IEEE80211_CCMP_HDR_LEN); 465 memmove(pos, pos + IEEE80211_CCMP_HDR_LEN, hdrlen); 466 467 /* the HW only needs room for the IV, but not the actual IV */ 468 if (info->control.hw_key && 469 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) 470 return 0; 471 472 pos += hdrlen; 473 474 pn64 = atomic64_inc_return(&key->conf.tx_pn); 475 476 pn[5] = pn64; 477 pn[4] = pn64 >> 8; 478 pn[3] = pn64 >> 16; 479 pn[2] = pn64 >> 24; 480 pn[1] = pn64 >> 32; 481 pn[0] = pn64 >> 40; 482 483 ccmp_pn2hdr(pos, pn, key->conf.keyidx); 484 485 /* hwaccel - with software CCMP header */ 486 if (info->control.hw_key) 487 return 0; 488 489 pos += IEEE80211_CCMP_HDR_LEN; 490 ccmp_special_blocks(skb, pn, b_0, aad, 491 key->conf.flags & IEEE80211_KEY_FLAG_SPP_AMSDU); 492 return ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, b_0, aad, pos, len, 493 skb_put(skb, mic_len)); 494 } 495 496 497 ieee80211_tx_result 498 ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx, 499 unsigned int mic_len) 500 { 501 struct sk_buff *skb; 502 503 ieee80211_tx_set_protected(tx); 504 505 skb_queue_walk(&tx->skbs, skb) { 506 if (ccmp_encrypt_skb(tx, skb, mic_len) < 0) 507 return TX_DROP; 508 } 509 510 return TX_CONTINUE; 511 } 512 513 514 ieee80211_rx_result 515 ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx, 516 unsigned int mic_len) 517 { 518 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 519 int hdrlen; 520 struct ieee80211_key *key = rx->key; 521 struct sk_buff *skb = rx->skb; 522 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 523 u8 pn[IEEE80211_CCMP_PN_LEN]; 524 int data_len; 525 int queue; 526 527 hdrlen = ieee80211_hdrlen(hdr->frame_control); 528 529 if (!ieee80211_is_data(hdr->frame_control) && 530 !ieee80211_is_robust_mgmt_frame(skb)) 531 return RX_CONTINUE; 532 533 if (status->flag & RX_FLAG_DECRYPTED) { 534 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_CCMP_HDR_LEN)) 535 return RX_DROP_U_SHORT_CCMP; 536 if (status->flag & RX_FLAG_MIC_STRIPPED) 537 mic_len = 0; 538 } else { 539 if (skb_linearize(rx->skb)) 540 return RX_DROP_U_OOM; 541 } 542 543 /* reload hdr - skb might have been reallocated */ 544 hdr = (void *)rx->skb->data; 545 546 data_len = skb->len - hdrlen - IEEE80211_CCMP_HDR_LEN - mic_len; 547 if (!rx->sta || data_len < 0) 548 return RX_DROP_U_SHORT_CCMP; 549 550 if (!(status->flag & RX_FLAG_PN_VALIDATED)) { 551 int res; 552 553 ccmp_hdr2pn(pn, skb->data + hdrlen); 554 555 queue = rx->security_idx; 556 557 res = memcmp(pn, key->u.ccmp.rx_pn[queue], 558 IEEE80211_CCMP_PN_LEN); 559 if (res < 0 || 560 (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) { 561 key->u.ccmp.replays++; 562 return RX_DROP_U_REPLAY; 563 } 564 565 if (!(status->flag & RX_FLAG_DECRYPTED)) { 566 u8 aad[2 * AES_BLOCK_SIZE]; 567 u8 b_0[AES_BLOCK_SIZE]; 568 /* hardware didn't decrypt/verify MIC */ 569 ccmp_special_blocks(skb, pn, b_0, aad, 570 key->conf.flags & IEEE80211_KEY_FLAG_SPP_AMSDU); 571 572 if (ieee80211_aes_ccm_decrypt( 573 key->u.ccmp.tfm, b_0, aad, 574 skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN, 575 data_len, 576 skb->data + skb->len - mic_len)) 577 return RX_DROP_U_MIC_FAIL; 578 } 579 580 memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN); 581 if (unlikely(ieee80211_is_frag(hdr))) 582 memcpy(rx->ccm_gcm.pn, pn, IEEE80211_CCMP_PN_LEN); 583 } 584 585 /* Remove CCMP header and MIC */ 586 if (pskb_trim(skb, skb->len - mic_len)) 587 return RX_DROP_U_SHORT_CCMP_MIC; 588 memmove(skb->data + IEEE80211_CCMP_HDR_LEN, skb->data, hdrlen); 589 skb_pull(skb, IEEE80211_CCMP_HDR_LEN); 590 591 return RX_CONTINUE; 592 } 593 594 static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad, 595 bool spp_amsdu) 596 { 597 struct ieee80211_hdr *hdr = (void *)skb->data; 598 599 memcpy(j_0, hdr->addr2, ETH_ALEN); 600 memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN); 601 j_0[13] = 0; 602 j_0[14] = 0; 603 j_0[AES_BLOCK_SIZE - 1] = 0x01; 604 605 ccmp_gcmp_aad(skb, aad, spp_amsdu); 606 } 607 608 static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id) 609 { 610 hdr[0] = pn[5]; 611 hdr[1] = pn[4]; 612 hdr[2] = 0; 613 hdr[3] = 0x20 | (key_id << 6); 614 hdr[4] = pn[3]; 615 hdr[5] = pn[2]; 616 hdr[6] = pn[1]; 617 hdr[7] = pn[0]; 618 } 619 620 static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr) 621 { 622 pn[0] = hdr[7]; 623 pn[1] = hdr[6]; 624 pn[2] = hdr[5]; 625 pn[3] = hdr[4]; 626 pn[4] = hdr[1]; 627 pn[5] = hdr[0]; 628 } 629 630 static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) 631 { 632 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 633 struct ieee80211_key *key = tx->key; 634 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 635 int hdrlen, len, tail; 636 u8 *pos; 637 u8 pn[6]; 638 u64 pn64; 639 u8 aad[GCM_AAD_LEN]; 640 u8 j_0[AES_BLOCK_SIZE]; 641 642 if (info->control.hw_key && 643 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) && 644 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) && 645 !((info->control.hw_key->flags & 646 IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) && 647 ieee80211_is_mgmt(hdr->frame_control))) { 648 /* hwaccel has no need for preallocated room for GCMP 649 * header or MIC fields 650 */ 651 return 0; 652 } 653 654 hdrlen = ieee80211_hdrlen(hdr->frame_control); 655 len = skb->len - hdrlen; 656 657 if (info->control.hw_key) 658 tail = 0; 659 else 660 tail = IEEE80211_GCMP_MIC_LEN; 661 662 if (WARN_ON(skb_tailroom(skb) < tail || 663 skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN)) 664 return -1; 665 666 pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN); 667 memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen); 668 skb_set_network_header(skb, skb_network_offset(skb) + 669 IEEE80211_GCMP_HDR_LEN); 670 671 /* the HW only needs room for the IV, but not the actual IV */ 672 if (info->control.hw_key && 673 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) 674 return 0; 675 676 pos += hdrlen; 677 678 pn64 = atomic64_inc_return(&key->conf.tx_pn); 679 680 pn[5] = pn64; 681 pn[4] = pn64 >> 8; 682 pn[3] = pn64 >> 16; 683 pn[2] = pn64 >> 24; 684 pn[1] = pn64 >> 32; 685 pn[0] = pn64 >> 40; 686 687 gcmp_pn2hdr(pos, pn, key->conf.keyidx); 688 689 /* hwaccel - with software GCMP header */ 690 if (info->control.hw_key) 691 return 0; 692 693 pos += IEEE80211_GCMP_HDR_LEN; 694 gcmp_special_blocks(skb, pn, j_0, aad, 695 key->conf.flags & IEEE80211_KEY_FLAG_SPP_AMSDU); 696 return ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len, 697 skb_put(skb, IEEE80211_GCMP_MIC_LEN)); 698 } 699 700 ieee80211_tx_result 701 ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx) 702 { 703 struct sk_buff *skb; 704 705 ieee80211_tx_set_protected(tx); 706 707 skb_queue_walk(&tx->skbs, skb) { 708 if (gcmp_encrypt_skb(tx, skb) < 0) 709 return TX_DROP; 710 } 711 712 return TX_CONTINUE; 713 } 714 715 ieee80211_rx_result 716 ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx) 717 { 718 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 719 int hdrlen; 720 struct ieee80211_key *key = rx->key; 721 struct sk_buff *skb = rx->skb; 722 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 723 u8 pn[IEEE80211_GCMP_PN_LEN]; 724 int data_len, queue, mic_len = IEEE80211_GCMP_MIC_LEN; 725 726 hdrlen = ieee80211_hdrlen(hdr->frame_control); 727 728 if (!ieee80211_is_data(hdr->frame_control) && 729 !ieee80211_is_robust_mgmt_frame(skb)) 730 return RX_CONTINUE; 731 732 if (status->flag & RX_FLAG_DECRYPTED) { 733 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN)) 734 return RX_DROP_U_SHORT_GCMP; 735 if (status->flag & RX_FLAG_MIC_STRIPPED) 736 mic_len = 0; 737 } else { 738 if (skb_linearize(rx->skb)) 739 return RX_DROP_U_OOM; 740 } 741 742 /* reload hdr - skb might have been reallocated */ 743 hdr = (void *)rx->skb->data; 744 745 data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN - mic_len; 746 if (!rx->sta || data_len < 0) 747 return RX_DROP_U_SHORT_GCMP; 748 749 if (!(status->flag & RX_FLAG_PN_VALIDATED)) { 750 int res; 751 752 gcmp_hdr2pn(pn, skb->data + hdrlen); 753 754 queue = rx->security_idx; 755 756 res = memcmp(pn, key->u.gcmp.rx_pn[queue], 757 IEEE80211_GCMP_PN_LEN); 758 if (res < 0 || 759 (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) { 760 key->u.gcmp.replays++; 761 return RX_DROP_U_REPLAY; 762 } 763 764 if (!(status->flag & RX_FLAG_DECRYPTED)) { 765 u8 aad[2 * AES_BLOCK_SIZE]; 766 u8 j_0[AES_BLOCK_SIZE]; 767 /* hardware didn't decrypt/verify MIC */ 768 gcmp_special_blocks(skb, pn, j_0, aad, 769 key->conf.flags & IEEE80211_KEY_FLAG_SPP_AMSDU); 770 771 if (ieee80211_aes_gcm_decrypt( 772 key->u.gcmp.tfm, j_0, aad, 773 skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN, 774 data_len, 775 skb->data + skb->len - 776 IEEE80211_GCMP_MIC_LEN)) 777 return RX_DROP_U_MIC_FAIL; 778 } 779 780 memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN); 781 if (unlikely(ieee80211_is_frag(hdr))) 782 memcpy(rx->ccm_gcm.pn, pn, IEEE80211_CCMP_PN_LEN); 783 } 784 785 /* Remove GCMP header and MIC */ 786 if (pskb_trim(skb, skb->len - mic_len)) 787 return RX_DROP_U_SHORT_GCMP_MIC; 788 memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen); 789 skb_pull(skb, IEEE80211_GCMP_HDR_LEN); 790 791 return RX_CONTINUE; 792 } 793 794 static void bip_aad(struct sk_buff *skb, u8 *aad) 795 { 796 __le16 mask_fc; 797 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 798 799 /* BIP AAD: FC(masked) || A1 || A2 || A3 */ 800 801 /* FC type/subtype */ 802 /* Mask FC Retry, PwrMgt, MoreData flags to zero */ 803 mask_fc = hdr->frame_control; 804 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM | 805 IEEE80211_FCTL_MOREDATA); 806 put_unaligned(mask_fc, (__le16 *) &aad[0]); 807 /* A1 || A2 || A3 */ 808 memcpy(aad + 2, &hdr->addrs, 3 * ETH_ALEN); 809 } 810 811 812 static inline void bip_ipn_set64(u8 *d, u64 pn) 813 { 814 *d++ = pn; 815 *d++ = pn >> 8; 816 *d++ = pn >> 16; 817 *d++ = pn >> 24; 818 *d++ = pn >> 32; 819 *d = pn >> 40; 820 } 821 822 static inline void bip_ipn_swap(u8 *d, const u8 *s) 823 { 824 *d++ = s[5]; 825 *d++ = s[4]; 826 *d++ = s[3]; 827 *d++ = s[2]; 828 *d++ = s[1]; 829 *d = s[0]; 830 } 831 832 833 ieee80211_tx_result 834 ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx) 835 { 836 struct sk_buff *skb; 837 struct ieee80211_tx_info *info; 838 struct ieee80211_key *key = tx->key; 839 struct ieee80211_mmie *mmie; 840 u8 aad[20]; 841 u64 pn64; 842 843 if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) 844 return TX_DROP; 845 846 skb = skb_peek(&tx->skbs); 847 848 info = IEEE80211_SKB_CB(skb); 849 850 if (info->control.hw_key && 851 !(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIE)) 852 return TX_CONTINUE; 853 854 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) 855 return TX_DROP; 856 857 mmie = skb_put(skb, sizeof(*mmie)); 858 mmie->element_id = WLAN_EID_MMIE; 859 mmie->length = sizeof(*mmie) - 2; 860 mmie->key_id = cpu_to_le16(key->conf.keyidx); 861 862 /* PN = PN + 1 */ 863 pn64 = atomic64_inc_return(&key->conf.tx_pn); 864 865 bip_ipn_set64(mmie->sequence_number, pn64); 866 867 if (info->control.hw_key) 868 return TX_CONTINUE; 869 870 bip_aad(skb, aad); 871 872 /* 873 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64) 874 */ 875 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad, 876 skb->data + 24, skb->len - 24, mmie->mic); 877 878 return TX_CONTINUE; 879 } 880 881 ieee80211_tx_result 882 ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx) 883 { 884 struct sk_buff *skb; 885 struct ieee80211_tx_info *info; 886 struct ieee80211_key *key = tx->key; 887 struct ieee80211_mmie_16 *mmie; 888 u8 aad[20]; 889 u64 pn64; 890 891 if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) 892 return TX_DROP; 893 894 skb = skb_peek(&tx->skbs); 895 896 info = IEEE80211_SKB_CB(skb); 897 898 if (info->control.hw_key && 899 !(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIE)) 900 return TX_CONTINUE; 901 902 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) 903 return TX_DROP; 904 905 mmie = skb_put(skb, sizeof(*mmie)); 906 mmie->element_id = WLAN_EID_MMIE; 907 mmie->length = sizeof(*mmie) - 2; 908 mmie->key_id = cpu_to_le16(key->conf.keyidx); 909 910 /* PN = PN + 1 */ 911 pn64 = atomic64_inc_return(&key->conf.tx_pn); 912 913 bip_ipn_set64(mmie->sequence_number, pn64); 914 915 if (info->control.hw_key) 916 return TX_CONTINUE; 917 918 bip_aad(skb, aad); 919 920 /* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128) 921 */ 922 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad, 923 skb->data + 24, skb->len - 24, mmie->mic); 924 925 return TX_CONTINUE; 926 } 927 928 ieee80211_rx_result 929 ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx) 930 { 931 struct sk_buff *skb = rx->skb; 932 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 933 struct ieee80211_key *key = rx->key; 934 struct ieee80211_mmie *mmie; 935 u8 aad[20], mic[8], ipn[6]; 936 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 937 938 if (!ieee80211_is_mgmt(hdr->frame_control)) 939 return RX_CONTINUE; 940 941 /* management frames are already linear */ 942 943 if (skb->len < 24 + sizeof(*mmie)) 944 return RX_DROP_U_SHORT_CMAC; 945 946 mmie = (struct ieee80211_mmie *) 947 (skb->data + skb->len - sizeof(*mmie)); 948 if (mmie->element_id != WLAN_EID_MMIE || 949 mmie->length != sizeof(*mmie) - 2) 950 return RX_DROP_U_BAD_MMIE; /* Invalid MMIE */ 951 952 bip_ipn_swap(ipn, mmie->sequence_number); 953 954 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) { 955 key->u.aes_cmac.replays++; 956 return RX_DROP_U_REPLAY; 957 } 958 959 if (!(status->flag & RX_FLAG_DECRYPTED)) { 960 /* hardware didn't decrypt/verify MIC */ 961 bip_aad(skb, aad); 962 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad, 963 skb->data + 24, skb->len - 24, mic); 964 if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) { 965 key->u.aes_cmac.icverrors++; 966 return RX_DROP_U_MIC_FAIL; 967 } 968 } 969 970 memcpy(key->u.aes_cmac.rx_pn, ipn, 6); 971 972 /* Remove MMIE */ 973 skb_trim(skb, skb->len - sizeof(*mmie)); 974 975 return RX_CONTINUE; 976 } 977 978 ieee80211_rx_result 979 ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx) 980 { 981 struct sk_buff *skb = rx->skb; 982 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 983 struct ieee80211_key *key = rx->key; 984 struct ieee80211_mmie_16 *mmie; 985 u8 aad[20], mic[16], ipn[6]; 986 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 987 988 if (!ieee80211_is_mgmt(hdr->frame_control)) 989 return RX_CONTINUE; 990 991 /* management frames are already linear */ 992 993 if (skb->len < 24 + sizeof(*mmie)) 994 return RX_DROP_U_SHORT_CMAC256; 995 996 mmie = (struct ieee80211_mmie_16 *) 997 (skb->data + skb->len - sizeof(*mmie)); 998 if (mmie->element_id != WLAN_EID_MMIE || 999 mmie->length != sizeof(*mmie) - 2) 1000 return RX_DROP_U_BAD_MMIE; /* Invalid MMIE */ 1001 1002 bip_ipn_swap(ipn, mmie->sequence_number); 1003 1004 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) { 1005 key->u.aes_cmac.replays++; 1006 return RX_DROP_U_REPLAY; 1007 } 1008 1009 if (!(status->flag & RX_FLAG_DECRYPTED)) { 1010 /* hardware didn't decrypt/verify MIC */ 1011 bip_aad(skb, aad); 1012 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad, 1013 skb->data + 24, skb->len - 24, mic); 1014 if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) { 1015 key->u.aes_cmac.icverrors++; 1016 return RX_DROP_U_MIC_FAIL; 1017 } 1018 } 1019 1020 memcpy(key->u.aes_cmac.rx_pn, ipn, 6); 1021 1022 /* Remove MMIE */ 1023 skb_trim(skb, skb->len - sizeof(*mmie)); 1024 1025 return RX_CONTINUE; 1026 } 1027 1028 ieee80211_tx_result 1029 ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx) 1030 { 1031 struct sk_buff *skb; 1032 struct ieee80211_tx_info *info; 1033 struct ieee80211_key *key = tx->key; 1034 struct ieee80211_mmie_16 *mmie; 1035 struct ieee80211_hdr *hdr; 1036 u8 aad[GMAC_AAD_LEN]; 1037 u64 pn64; 1038 u8 nonce[GMAC_NONCE_LEN]; 1039 1040 if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) 1041 return TX_DROP; 1042 1043 skb = skb_peek(&tx->skbs); 1044 1045 info = IEEE80211_SKB_CB(skb); 1046 1047 if (info->control.hw_key && 1048 !(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIE)) 1049 return TX_CONTINUE; 1050 1051 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) 1052 return TX_DROP; 1053 1054 mmie = skb_put(skb, sizeof(*mmie)); 1055 mmie->element_id = WLAN_EID_MMIE; 1056 mmie->length = sizeof(*mmie) - 2; 1057 mmie->key_id = cpu_to_le16(key->conf.keyidx); 1058 1059 /* PN = PN + 1 */ 1060 pn64 = atomic64_inc_return(&key->conf.tx_pn); 1061 1062 bip_ipn_set64(mmie->sequence_number, pn64); 1063 1064 if (info->control.hw_key) 1065 return TX_CONTINUE; 1066 1067 bip_aad(skb, aad); 1068 1069 hdr = (struct ieee80211_hdr *)skb->data; 1070 memcpy(nonce, hdr->addr2, ETH_ALEN); 1071 bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number); 1072 1073 /* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */ 1074 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce, 1075 skb->data + 24, skb->len - 24, mmie->mic) < 0) 1076 return TX_DROP; 1077 1078 return TX_CONTINUE; 1079 } 1080 1081 ieee80211_rx_result 1082 ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx) 1083 { 1084 struct sk_buff *skb = rx->skb; 1085 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1086 struct ieee80211_key *key = rx->key; 1087 struct ieee80211_mmie_16 *mmie; 1088 u8 aad[GMAC_AAD_LEN], *mic, ipn[6], nonce[GMAC_NONCE_LEN]; 1089 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1090 1091 if (!ieee80211_is_mgmt(hdr->frame_control)) 1092 return RX_CONTINUE; 1093 1094 /* management frames are already linear */ 1095 1096 if (skb->len < 24 + sizeof(*mmie)) 1097 return RX_DROP_U_SHORT_GMAC; 1098 1099 mmie = (struct ieee80211_mmie_16 *) 1100 (skb->data + skb->len - sizeof(*mmie)); 1101 if (mmie->element_id != WLAN_EID_MMIE || 1102 mmie->length != sizeof(*mmie) - 2) 1103 return RX_DROP_U_BAD_MMIE; /* Invalid MMIE */ 1104 1105 bip_ipn_swap(ipn, mmie->sequence_number); 1106 1107 if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) { 1108 key->u.aes_gmac.replays++; 1109 return RX_DROP_U_REPLAY; 1110 } 1111 1112 if (!(status->flag & RX_FLAG_DECRYPTED)) { 1113 /* hardware didn't decrypt/verify MIC */ 1114 bip_aad(skb, aad); 1115 1116 memcpy(nonce, hdr->addr2, ETH_ALEN); 1117 memcpy(nonce + ETH_ALEN, ipn, 6); 1118 1119 mic = kmalloc(GMAC_MIC_LEN, GFP_ATOMIC); 1120 if (!mic) 1121 return RX_DROP_U_OOM; 1122 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce, 1123 skb->data + 24, skb->len - 24, 1124 mic) < 0 || 1125 crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) { 1126 key->u.aes_gmac.icverrors++; 1127 kfree(mic); 1128 return RX_DROP_U_MIC_FAIL; 1129 } 1130 kfree(mic); 1131 } 1132 1133 memcpy(key->u.aes_gmac.rx_pn, ipn, 6); 1134 1135 /* Remove MMIE */ 1136 skb_trim(skb, skb->len - sizeof(*mmie)); 1137 1138 return RX_CONTINUE; 1139 } 1140