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); 601 602 ccmp_gcmp_aad(skb, aad, spp_amsdu); 603 } 604 605 static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id) 606 { 607 hdr[0] = pn[5]; 608 hdr[1] = pn[4]; 609 hdr[2] = 0; 610 hdr[3] = 0x20 | (key_id << 6); 611 hdr[4] = pn[3]; 612 hdr[5] = pn[2]; 613 hdr[6] = pn[1]; 614 hdr[7] = pn[0]; 615 } 616 617 static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr) 618 { 619 pn[0] = hdr[7]; 620 pn[1] = hdr[6]; 621 pn[2] = hdr[5]; 622 pn[3] = hdr[4]; 623 pn[4] = hdr[1]; 624 pn[5] = hdr[0]; 625 } 626 627 static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) 628 { 629 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 630 struct ieee80211_key *key = tx->key; 631 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 632 int hdrlen, len, tail; 633 u8 *pos; 634 u8 pn[6]; 635 u64 pn64; 636 u8 aad[GCM_AAD_LEN]; 637 u8 j_0[AES_BLOCK_SIZE]; 638 639 if (info->control.hw_key && 640 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) && 641 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) && 642 !((info->control.hw_key->flags & 643 IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) && 644 ieee80211_is_mgmt(hdr->frame_control))) { 645 /* hwaccel has no need for preallocated room for GCMP 646 * header or MIC fields 647 */ 648 return 0; 649 } 650 651 hdrlen = ieee80211_hdrlen(hdr->frame_control); 652 len = skb->len - hdrlen; 653 654 if (info->control.hw_key) 655 tail = 0; 656 else 657 tail = IEEE80211_GCMP_MIC_LEN; 658 659 if (WARN_ON(skb_tailroom(skb) < tail || 660 skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN)) 661 return -1; 662 663 pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN); 664 memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen); 665 skb_set_network_header(skb, skb_network_offset(skb) + 666 IEEE80211_GCMP_HDR_LEN); 667 668 /* the HW only needs room for the IV, but not the actual IV */ 669 if (info->control.hw_key && 670 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) 671 return 0; 672 673 pos += hdrlen; 674 675 pn64 = atomic64_inc_return(&key->conf.tx_pn); 676 677 pn[5] = pn64; 678 pn[4] = pn64 >> 8; 679 pn[3] = pn64 >> 16; 680 pn[2] = pn64 >> 24; 681 pn[1] = pn64 >> 32; 682 pn[0] = pn64 >> 40; 683 684 gcmp_pn2hdr(pos, pn, key->conf.keyidx); 685 686 /* hwaccel - with software GCMP header */ 687 if (info->control.hw_key) 688 return 0; 689 690 pos += IEEE80211_GCMP_HDR_LEN; 691 gcmp_special_blocks(skb, pn, j_0, aad, 692 key->conf.flags & IEEE80211_KEY_FLAG_SPP_AMSDU); 693 return ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len, 694 skb_put(skb, IEEE80211_GCMP_MIC_LEN)); 695 } 696 697 ieee80211_tx_result 698 ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx) 699 { 700 struct sk_buff *skb; 701 702 ieee80211_tx_set_protected(tx); 703 704 skb_queue_walk(&tx->skbs, skb) { 705 if (gcmp_encrypt_skb(tx, skb) < 0) 706 return TX_DROP; 707 } 708 709 return TX_CONTINUE; 710 } 711 712 ieee80211_rx_result 713 ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx) 714 { 715 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data; 716 int hdrlen; 717 struct ieee80211_key *key = rx->key; 718 struct sk_buff *skb = rx->skb; 719 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 720 u8 pn[IEEE80211_GCMP_PN_LEN]; 721 int data_len, queue, mic_len = IEEE80211_GCMP_MIC_LEN; 722 723 hdrlen = ieee80211_hdrlen(hdr->frame_control); 724 725 if (!ieee80211_is_data(hdr->frame_control) && 726 !ieee80211_is_robust_mgmt_frame(skb)) 727 return RX_CONTINUE; 728 729 if (status->flag & RX_FLAG_DECRYPTED) { 730 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN)) 731 return RX_DROP_U_SHORT_GCMP; 732 if (status->flag & RX_FLAG_MIC_STRIPPED) 733 mic_len = 0; 734 } else { 735 if (skb_linearize(rx->skb)) 736 return RX_DROP_U_OOM; 737 } 738 739 /* reload hdr - skb might have been reallocated */ 740 hdr = (void *)rx->skb->data; 741 742 data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN - mic_len; 743 if (!rx->sta || data_len < 0) 744 return RX_DROP_U_SHORT_GCMP; 745 746 if (!(status->flag & RX_FLAG_PN_VALIDATED)) { 747 int res; 748 749 gcmp_hdr2pn(pn, skb->data + hdrlen); 750 751 queue = rx->security_idx; 752 753 res = memcmp(pn, key->u.gcmp.rx_pn[queue], 754 IEEE80211_GCMP_PN_LEN); 755 if (res < 0 || 756 (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) { 757 key->u.gcmp.replays++; 758 return RX_DROP_U_REPLAY; 759 } 760 761 if (!(status->flag & RX_FLAG_DECRYPTED)) { 762 u8 aad[2 * AES_BLOCK_SIZE]; 763 u8 j_0[AES_BLOCK_SIZE]; 764 /* hardware didn't decrypt/verify MIC */ 765 gcmp_special_blocks(skb, pn, j_0, aad, 766 key->conf.flags & IEEE80211_KEY_FLAG_SPP_AMSDU); 767 768 if (ieee80211_aes_gcm_decrypt( 769 key->u.gcmp.tfm, j_0, aad, 770 skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN, 771 data_len, 772 skb->data + skb->len - 773 IEEE80211_GCMP_MIC_LEN)) 774 return RX_DROP_U_MIC_FAIL; 775 } 776 777 memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN); 778 if (unlikely(ieee80211_is_frag(hdr))) 779 memcpy(rx->ccm_gcm.pn, pn, IEEE80211_CCMP_PN_LEN); 780 } 781 782 /* Remove GCMP header and MIC */ 783 if (pskb_trim(skb, skb->len - mic_len)) 784 return RX_DROP_U_SHORT_GCMP_MIC; 785 memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen); 786 skb_pull(skb, IEEE80211_GCMP_HDR_LEN); 787 788 return RX_CONTINUE; 789 } 790 791 static void bip_aad(struct sk_buff *skb, u8 *aad) 792 { 793 __le16 mask_fc; 794 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 795 796 /* BIP AAD: FC(masked) || A1 || A2 || A3 */ 797 798 /* FC type/subtype */ 799 /* Mask FC Retry, PwrMgt, MoreData flags to zero */ 800 mask_fc = hdr->frame_control; 801 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM | 802 IEEE80211_FCTL_MOREDATA); 803 put_unaligned(mask_fc, (__le16 *) &aad[0]); 804 /* A1 || A2 || A3 */ 805 memcpy(aad + 2, &hdr->addrs, 3 * ETH_ALEN); 806 } 807 808 809 static inline void bip_ipn_set64(u8 *d, u64 pn) 810 { 811 *d++ = pn; 812 *d++ = pn >> 8; 813 *d++ = pn >> 16; 814 *d++ = pn >> 24; 815 *d++ = pn >> 32; 816 *d = pn >> 40; 817 } 818 819 static inline void bip_ipn_swap(u8 *d, const u8 *s) 820 { 821 *d++ = s[5]; 822 *d++ = s[4]; 823 *d++ = s[3]; 824 *d++ = s[2]; 825 *d++ = s[1]; 826 *d = s[0]; 827 } 828 829 830 ieee80211_tx_result 831 ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx) 832 { 833 struct sk_buff *skb; 834 struct ieee80211_tx_info *info; 835 struct ieee80211_key *key = tx->key; 836 struct ieee80211_mmie *mmie; 837 u8 aad[20]; 838 u64 pn64; 839 840 if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) 841 return TX_DROP; 842 843 skb = skb_peek(&tx->skbs); 844 845 info = IEEE80211_SKB_CB(skb); 846 847 if (info->control.hw_key && 848 !(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIE)) 849 return TX_CONTINUE; 850 851 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) 852 return TX_DROP; 853 854 mmie = skb_put(skb, sizeof(*mmie)); 855 mmie->element_id = WLAN_EID_MMIE; 856 mmie->length = sizeof(*mmie) - 2; 857 mmie->key_id = cpu_to_le16(key->conf.keyidx); 858 859 /* PN = PN + 1 */ 860 pn64 = atomic64_inc_return(&key->conf.tx_pn); 861 862 bip_ipn_set64(mmie->sequence_number, pn64); 863 864 if (info->control.hw_key) 865 return TX_CONTINUE; 866 867 bip_aad(skb, aad); 868 869 /* 870 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64) 871 */ 872 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad, 873 skb->data + 24, skb->len - 24, mmie->mic); 874 875 return TX_CONTINUE; 876 } 877 878 ieee80211_tx_result 879 ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx) 880 { 881 struct sk_buff *skb; 882 struct ieee80211_tx_info *info; 883 struct ieee80211_key *key = tx->key; 884 struct ieee80211_mmie_16 *mmie; 885 u8 aad[20]; 886 u64 pn64; 887 888 if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) 889 return TX_DROP; 890 891 skb = skb_peek(&tx->skbs); 892 893 info = IEEE80211_SKB_CB(skb); 894 895 if (info->control.hw_key && 896 !(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIE)) 897 return TX_CONTINUE; 898 899 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) 900 return TX_DROP; 901 902 mmie = skb_put(skb, sizeof(*mmie)); 903 mmie->element_id = WLAN_EID_MMIE; 904 mmie->length = sizeof(*mmie) - 2; 905 mmie->key_id = cpu_to_le16(key->conf.keyidx); 906 907 /* PN = PN + 1 */ 908 pn64 = atomic64_inc_return(&key->conf.tx_pn); 909 910 bip_ipn_set64(mmie->sequence_number, pn64); 911 912 if (info->control.hw_key) 913 return TX_CONTINUE; 914 915 bip_aad(skb, aad); 916 917 /* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128) 918 */ 919 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad, 920 skb->data + 24, skb->len - 24, mmie->mic); 921 922 return TX_CONTINUE; 923 } 924 925 ieee80211_rx_result 926 ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx) 927 { 928 struct sk_buff *skb = rx->skb; 929 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 930 struct ieee80211_key *key = rx->key; 931 struct ieee80211_mmie *mmie; 932 u8 aad[20], mic[8], ipn[6]; 933 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 934 935 if (!ieee80211_is_mgmt(hdr->frame_control)) 936 return RX_CONTINUE; 937 938 /* management frames are already linear */ 939 940 if (skb->len < 24 + sizeof(*mmie)) 941 return RX_DROP_U_SHORT_CMAC; 942 943 mmie = (struct ieee80211_mmie *) 944 (skb->data + skb->len - sizeof(*mmie)); 945 if (mmie->element_id != WLAN_EID_MMIE || 946 mmie->length != sizeof(*mmie) - 2) 947 return RX_DROP_U_BAD_MMIE; /* Invalid MMIE */ 948 949 bip_ipn_swap(ipn, mmie->sequence_number); 950 951 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) { 952 key->u.aes_cmac.replays++; 953 return RX_DROP_U_REPLAY; 954 } 955 956 if (!(status->flag & RX_FLAG_DECRYPTED)) { 957 /* hardware didn't decrypt/verify MIC */ 958 bip_aad(skb, aad); 959 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad, 960 skb->data + 24, skb->len - 24, mic); 961 if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) { 962 key->u.aes_cmac.icverrors++; 963 return RX_DROP_U_MIC_FAIL; 964 } 965 } 966 967 memcpy(key->u.aes_cmac.rx_pn, ipn, 6); 968 969 /* Remove MMIE */ 970 skb_trim(skb, skb->len - sizeof(*mmie)); 971 972 return RX_CONTINUE; 973 } 974 975 ieee80211_rx_result 976 ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx) 977 { 978 struct sk_buff *skb = rx->skb; 979 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 980 struct ieee80211_key *key = rx->key; 981 struct ieee80211_mmie_16 *mmie; 982 u8 aad[20], mic[16], ipn[6]; 983 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 984 985 if (!ieee80211_is_mgmt(hdr->frame_control)) 986 return RX_CONTINUE; 987 988 /* management frames are already linear */ 989 990 if (skb->len < 24 + sizeof(*mmie)) 991 return RX_DROP_U_SHORT_CMAC256; 992 993 mmie = (struct ieee80211_mmie_16 *) 994 (skb->data + skb->len - sizeof(*mmie)); 995 if (mmie->element_id != WLAN_EID_MMIE || 996 mmie->length != sizeof(*mmie) - 2) 997 return RX_DROP_U_BAD_MMIE; /* Invalid MMIE */ 998 999 bip_ipn_swap(ipn, mmie->sequence_number); 1000 1001 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) { 1002 key->u.aes_cmac.replays++; 1003 return RX_DROP_U_REPLAY; 1004 } 1005 1006 if (!(status->flag & RX_FLAG_DECRYPTED)) { 1007 /* hardware didn't decrypt/verify MIC */ 1008 bip_aad(skb, aad); 1009 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad, 1010 skb->data + 24, skb->len - 24, mic); 1011 if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) { 1012 key->u.aes_cmac.icverrors++; 1013 return RX_DROP_U_MIC_FAIL; 1014 } 1015 } 1016 1017 memcpy(key->u.aes_cmac.rx_pn, ipn, 6); 1018 1019 /* Remove MMIE */ 1020 skb_trim(skb, skb->len - sizeof(*mmie)); 1021 1022 return RX_CONTINUE; 1023 } 1024 1025 ieee80211_tx_result 1026 ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx) 1027 { 1028 struct sk_buff *skb; 1029 struct ieee80211_tx_info *info; 1030 struct ieee80211_key *key = tx->key; 1031 struct ieee80211_mmie_16 *mmie; 1032 struct ieee80211_hdr *hdr; 1033 u8 aad[GMAC_AAD_LEN]; 1034 u64 pn64; 1035 u8 nonce[GMAC_NONCE_LEN]; 1036 1037 if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) 1038 return TX_DROP; 1039 1040 skb = skb_peek(&tx->skbs); 1041 1042 info = IEEE80211_SKB_CB(skb); 1043 1044 if (info->control.hw_key && 1045 !(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIE)) 1046 return TX_CONTINUE; 1047 1048 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) 1049 return TX_DROP; 1050 1051 mmie = skb_put(skb, sizeof(*mmie)); 1052 mmie->element_id = WLAN_EID_MMIE; 1053 mmie->length = sizeof(*mmie) - 2; 1054 mmie->key_id = cpu_to_le16(key->conf.keyidx); 1055 1056 /* PN = PN + 1 */ 1057 pn64 = atomic64_inc_return(&key->conf.tx_pn); 1058 1059 bip_ipn_set64(mmie->sequence_number, pn64); 1060 1061 if (info->control.hw_key) 1062 return TX_CONTINUE; 1063 1064 bip_aad(skb, aad); 1065 1066 hdr = (struct ieee80211_hdr *)skb->data; 1067 memcpy(nonce, hdr->addr2, ETH_ALEN); 1068 bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number); 1069 1070 /* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */ 1071 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce, 1072 skb->data + 24, skb->len - 24, mmie->mic) < 0) 1073 return TX_DROP; 1074 1075 return TX_CONTINUE; 1076 } 1077 1078 ieee80211_rx_result 1079 ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx) 1080 { 1081 struct sk_buff *skb = rx->skb; 1082 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); 1083 struct ieee80211_key *key = rx->key; 1084 struct ieee80211_mmie_16 *mmie; 1085 u8 aad[GMAC_AAD_LEN], *mic, ipn[6], nonce[GMAC_NONCE_LEN]; 1086 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; 1087 1088 if (!ieee80211_is_mgmt(hdr->frame_control)) 1089 return RX_CONTINUE; 1090 1091 /* management frames are already linear */ 1092 1093 if (skb->len < 24 + sizeof(*mmie)) 1094 return RX_DROP_U_SHORT_GMAC; 1095 1096 mmie = (struct ieee80211_mmie_16 *) 1097 (skb->data + skb->len - sizeof(*mmie)); 1098 if (mmie->element_id != WLAN_EID_MMIE || 1099 mmie->length != sizeof(*mmie) - 2) 1100 return RX_DROP_U_BAD_MMIE; /* Invalid MMIE */ 1101 1102 bip_ipn_swap(ipn, mmie->sequence_number); 1103 1104 if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) { 1105 key->u.aes_gmac.replays++; 1106 return RX_DROP_U_REPLAY; 1107 } 1108 1109 if (!(status->flag & RX_FLAG_DECRYPTED)) { 1110 /* hardware didn't decrypt/verify MIC */ 1111 bip_aad(skb, aad); 1112 1113 memcpy(nonce, hdr->addr2, ETH_ALEN); 1114 memcpy(nonce + ETH_ALEN, ipn, 6); 1115 1116 mic = kmalloc(GMAC_MIC_LEN, GFP_ATOMIC); 1117 if (!mic) 1118 return RX_DROP_U_OOM; 1119 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce, 1120 skb->data + 24, skb->len - 24, 1121 mic) < 0 || 1122 crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) { 1123 key->u.aes_gmac.icverrors++; 1124 kfree(mic); 1125 return RX_DROP_U_MIC_FAIL; 1126 } 1127 kfree(mic); 1128 } 1129 1130 memcpy(key->u.aes_gmac.rx_pn, ipn, 6); 1131 1132 /* Remove MMIE */ 1133 skb_trim(skb, skb->len - sizeof(*mmie)); 1134 1135 return RX_CONTINUE; 1136 } 1137