net/mac80211/wpa.c

   1 /*
   2  * Copyright 2002-2004, Instant802 Networks, Inc.
   3  * Copyright 2008, Jouni Malinen <j@w1.fi>
   4  * Copyright (C) 2016-2017 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 #include <crypto/algapi.h>
  21
  22 #include "ieee80211_i.h"
  23 #include "michael.h"
  24 #include "tkip.h"
  25 #include "aes_ccm.h"
  26 #include "aes_cmac.h"
  27 #include "aes_gmac.h"
  28 #include "aes_gcm.h"
  29 #include "wpa.h"
  30
  31 ieee80211_tx_result
  32 ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
  33 {
  34         u8 *data, *key, *mic;
  35         size_t data_len;
  36         unsigned int hdrlen;
  37         struct ieee80211_hdr *hdr;
  38         struct sk_buff *skb = tx->skb;
  39         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  40         int tail;
  41
  42         hdr = (struct ieee80211_hdr *)skb->data;
  43         if (!tx->key || tx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
  44             skb->len < 24 || !ieee80211_is_data_present(hdr->frame_control))
  45                 return TX_CONTINUE;
  46
  47         hdrlen = ieee80211_hdrlen(hdr->frame_control);
  48         if (skb->len < hdrlen)
  49                 return TX_DROP;
  50
  51         data = skb->data + hdrlen;
  52         data_len = skb->len - hdrlen;
  53
  54         if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) {
  55                 /* Need to use software crypto for the test */
  56                 info->control.hw_key = NULL;
  57         }
  58
  59         if (info->control.hw_key &&
  60             (info->flags & IEEE80211_TX_CTL_DONTFRAG ||
  61              ieee80211_hw_check(&tx->local->hw, SUPPORTS_TX_FRAG)) &&
  62             !(tx->key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
  63                                      IEEE80211_KEY_FLAG_PUT_MIC_SPACE))) {
  64                 /* hwaccel - with no need for SW-generated MMIC or MIC space */
  65                 return TX_CONTINUE;
  66         }
  67
  68         tail = MICHAEL_MIC_LEN;
  69         if (!info->control.hw_key)
  70                 tail += IEEE80211_TKIP_ICV_LEN;
  71
  72         if (WARN(skb_tailroom(skb) < tail ||
  73                  skb_headroom(skb) < IEEE80211_TKIP_IV_LEN,
  74                  "mmic: not enough head/tail (%d/%d,%d/%d)\n",
  75                  skb_headroom(skb), IEEE80211_TKIP_IV_LEN,
  76                  skb_tailroom(skb), tail))
  77                 return TX_DROP;
  78
  79         mic = skb_put(skb, MICHAEL_MIC_LEN);
  80
  81         if (tx->key->conf.flags & IEEE80211_KEY_FLAG_PUT_MIC_SPACE) {
  82                 /* Zeroed MIC can help with debug */
  83                 memset(mic, 0, MICHAEL_MIC_LEN);
  84                 return TX_CONTINUE;
  85         }
  86
  87         key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY];
  88         michael_mic(key, hdr, data, data_len, mic);
  89         if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE))
  90                 mic[0]++;
  91
  92         return TX_CONTINUE;
  93 }
  94
  95
  96 ieee80211_rx_result
  97 ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
  98 {
  99         u8 *data, *key = NULL;
 100         size_t data_len;
 101         unsigned int hdrlen;
 102         u8 mic[MICHAEL_MIC_LEN];
 103         struct sk_buff *skb = rx->skb;
 104         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 105         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 106
 107         /*
 108          * it makes no sense to check for MIC errors on anything other
 109          * than data frames.
 110          */
 111         if (!ieee80211_is_data_present(hdr->frame_control))
 112                 return RX_CONTINUE;
 113
 114         /*
 115          * No way to verify the MIC if the hardware stripped it or
 116          * the IV with the key index. In this case we have solely rely
 117          * on the driver to set RX_FLAG_MMIC_ERROR in the event of a
 118          * MIC failure report.
 119          */
 120         if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) {
 121                 if (status->flag & RX_FLAG_MMIC_ERROR)
 122                         goto mic_fail_no_key;
 123
 124                 if (!(status->flag & RX_FLAG_IV_STRIPPED) && rx->key &&
 125                     rx->key->conf.cipher == WLAN_CIPHER_SUITE_TKIP)
 126                         goto update_iv;
 127
 128                 return RX_CONTINUE;
 129         }
 130
 131         /*
 132          * Some hardware seems to generate Michael MIC failure reports; even
 133          * though, the frame was not encrypted with TKIP and therefore has no
 134          * MIC. Ignore the flag them to avoid triggering countermeasures.
 135          */
 136         if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
 137             !(status->flag & RX_FLAG_DECRYPTED))
 138                 return RX_CONTINUE;
 139
 140         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) {
 141                 /*
 142                  * APs with pairwise keys should never receive Michael MIC
 143                  * errors for non-zero keyidx because these are reserved for
 144                  * group keys and only the AP is sending real multicast
 145                  * frames in the BSS.
 146                  */
 147                 return RX_DROP_UNUSABLE;
 148         }
 149
 150         if (status->flag & RX_FLAG_MMIC_ERROR)
 151                 goto mic_fail;
 152
 153         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 154         if (skb->len < hdrlen + MICHAEL_MIC_LEN)
 155                 return RX_DROP_UNUSABLE;
 156
 157         if (skb_linearize(rx->skb))
 158                 return RX_DROP_UNUSABLE;
 159         hdr = (void *)skb->data;
 160
 161         data = skb->data + hdrlen;
 162         data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;
 163         key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY];
 164         michael_mic(key, hdr, data, data_len, mic);
 165         if (crypto_memneq(mic, data + data_len, MICHAEL_MIC_LEN))
 166                 goto mic_fail;
 167
 168         /* remove Michael MIC from payload */
 169         skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
 170
 171 update_iv:
 172         /* update IV in key information to be able to detect replays */
 173         rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip_iv32;
 174         rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip_iv16;
 175
 176         return RX_CONTINUE;
 177
 178 mic_fail:
 179         rx->key->u.tkip.mic_failures++;
 180
 181 mic_fail_no_key:
 182         /*
 183          * In some cases the key can be unset - e.g. a multicast packet, in
 184          * a driver that supports HW encryption. Send up the key idx only if
 185          * the key is set.
 186          */
 187         cfg80211_michael_mic_failure(rx->sdata->dev, hdr->addr2,
 188                                      is_multicast_ether_addr(hdr->addr1) ?
 189                                      NL80211_KEYTYPE_GROUP :
 190                                      NL80211_KEYTYPE_PAIRWISE,
 191                                      rx->key ? rx->key->conf.keyidx : -1,
 192                                      NULL, GFP_ATOMIC);
 193         return RX_DROP_UNUSABLE;
 194 }
 195
 196 static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
 197 {
 198         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 199         struct ieee80211_key *key = tx->key;
 200         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 201         unsigned int hdrlen;
 202         int len, tail;
 203         u64 pn;
 204         u8 *pos;
 205
 206         if (info->control.hw_key &&
 207             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 208             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
 209                 /* hwaccel - with no need for software-generated IV */
 210                 return 0;
 211         }
 212
 213         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 214         len = skb->len - hdrlen;
 215
 216         if (info->control.hw_key)
 217                 tail = 0;
 218         else
 219                 tail = IEEE80211_TKIP_ICV_LEN;
 220
 221         if (WARN_ON(skb_tailroom(skb) < tail ||
 222                     skb_headroom(skb) < IEEE80211_TKIP_IV_LEN))
 223                 return -1;
 224
 225         pos = skb_push(skb, IEEE80211_TKIP_IV_LEN);
 226         memmove(pos, pos + IEEE80211_TKIP_IV_LEN, hdrlen);
 227         pos += hdrlen;
 228
 229         /* the HW only needs room for the IV, but not the actual IV */
 230         if (info->control.hw_key &&
 231             (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 232                 return 0;
 233
 234         /* Increase IV for the frame */
 235         pn = atomic64_inc_return(&key->conf.tx_pn);
 236         pos = ieee80211_tkip_add_iv(pos, &key->conf, pn);
 237
 238         /* hwaccel - with software IV */
 239         if (info->control.hw_key)
 240                 return 0;
 241
 242         /* Add room for ICV */
 243         skb_put(skb, IEEE80211_TKIP_ICV_LEN);
 244
 245         return ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,
 246                                            key, skb, pos, len);
 247 }
 248
 249
 250 ieee80211_tx_result
 251 ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
 252 {
 253         struct sk_buff *skb;
 254
 255         ieee80211_tx_set_protected(tx);
 256
 257         skb_queue_walk(&tx->skbs, skb) {
 258                 if (tkip_encrypt_skb(tx, skb) < 0)
 259                         return TX_DROP;
 260         }
 261
 262         return TX_CONTINUE;
 263 }
 264
 265
 266 ieee80211_rx_result
 267 ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
 268 {
 269         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 270         int hdrlen, res, hwaccel = 0;
 271         struct ieee80211_key *key = rx->key;
 272         struct sk_buff *skb = rx->skb;
 273         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 274
 275         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 276
 277         if (!ieee80211_is_data(hdr->frame_control))
 278                 return RX_CONTINUE;
 279
 280         if (!rx->sta || skb->len - hdrlen < 12)
 281                 return RX_DROP_UNUSABLE;
 282
 283         /* it may be possible to optimize this a bit more */
 284         if (skb_linearize(rx->skb))
 285                 return RX_DROP_UNUSABLE;
 286         hdr = (void *)skb->data;
 287
 288         /*
 289          * Let TKIP code verify IV, but skip decryption.
 290          * In the case where hardware checks the IV as well,
 291          * we don't even get here, see ieee80211_rx_h_decrypt()
 292          */
 293         if (status->flag & RX_FLAG_DECRYPTED)
 294                 hwaccel = 1;
 295
 296         res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm,
 297                                           key, skb->data + hdrlen,
 298                                           skb->len - hdrlen, rx->sta->sta.addr,
 299                                           hdr->addr1, hwaccel, rx->security_idx,
 300                                           &rx->tkip_iv32,
 301                                           &rx->tkip_iv16);
 302         if (res != TKIP_DECRYPT_OK)
 303                 return RX_DROP_UNUSABLE;
 304
 305         /* Trim ICV */
 306         if (!(status->flag & RX_FLAG_ICV_STRIPPED))
 307                 skb_trim(skb, skb->len - IEEE80211_TKIP_ICV_LEN);
 308
 309         /* Remove IV */
 310         memmove(skb->data + IEEE80211_TKIP_IV_LEN, skb->data, hdrlen);
 311         skb_pull(skb, IEEE80211_TKIP_IV_LEN);
 312
 313         return RX_CONTINUE;
 314 }
 315
 316
 317 static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad)
 318 {
 319         __le16 mask_fc;
 320         int a4_included, mgmt;
 321         u8 qos_tid;
 322         u16 len_a;
 323         unsigned int hdrlen;
 324         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 325
 326         /*
 327          * Mask FC: zero subtype b4 b5 b6 (if not mgmt)
 328          * Retry, PwrMgt, MoreData; 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         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 339         len_a = hdrlen - 2;
 340         a4_included = ieee80211_has_a4(hdr->frame_control);
 341
 342         if (ieee80211_is_data_qos(hdr->frame_control))
 343                 qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
 344         else
 345                 qos_tid = 0;
 346
 347         /* In CCM, the initial vectors (IV) used for CTR mode encryption and CBC
 348          * mode authentication are not allowed to collide, yet both are derived
 349          * from this vector b_0. We only set L := 1 here to indicate that the
 350          * data size can be represented in (L+1) bytes. The CCM layer will take
 351          * care of storing the data length in the top (L+1) bytes and setting
 352          * and clearing the other bits as is required to derive the two IVs.
 353          */
 354         b_0[0] = 0x1;
 355
 356         /* Nonce: Nonce Flags | A2 | PN
 357          * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7)
 358          */
 359         b_0[1] = qos_tid | (mgmt << 4);
 360         memcpy(&b_0[2], hdr->addr2, ETH_ALEN);
 361         memcpy(&b_0[8], pn, IEEE80211_CCMP_PN_LEN);
 362
 363         /* AAD (extra authenticate-only data) / masked 802.11 header
 364          * FC | A1 | A2 | A3 | SC | [A4] | [QC] */
 365         put_unaligned_be16(len_a, &aad[0]);
 366         put_unaligned(mask_fc, (__le16 *)&aad[2]);
 367         memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
 368
 369         /* Mask Seq#, leave Frag# */
 370         aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;
 371         aad[23] = 0;
 372
 373         if (a4_included) {
 374                 memcpy(&aad[24], hdr->addr4, ETH_ALEN);
 375                 aad[30] = qos_tid;
 376                 aad[31] = 0;
 377         } else {
 378                 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
 379                 aad[24] = qos_tid;
 380         }
 381 }
 382
 383
 384 static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)
 385 {
 386         hdr[0] = pn[5];
 387         hdr[1] = pn[4];
 388         hdr[2] = 0;
 389         hdr[3] = 0x20 | (key_id << 6);
 390         hdr[4] = pn[3];
 391         hdr[5] = pn[2];
 392         hdr[6] = pn[1];
 393         hdr[7] = pn[0];
 394 }
 395
 396
 397 static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr)
 398 {
 399         pn[0] = hdr[7];
 400         pn[1] = hdr[6];
 401         pn[2] = hdr[5];
 402         pn[3] = hdr[4];
 403         pn[4] = hdr[1];
 404         pn[5] = hdr[0];
 405 }
 406
 407
 408 static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb,
 409                             unsigned int mic_len)
 410 {
 411         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 412         struct ieee80211_key *key = tx->key;
 413         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 414         int hdrlen, len, tail;
 415         u8 *pos;
 416         u8 pn[6];
 417         u64 pn64;
 418         u8 aad[CCM_AAD_LEN];
 419         u8 b_0[AES_BLOCK_SIZE];
 420
 421         if (info->control.hw_key &&
 422             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 423             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 424             !((info->control.hw_key->flags &
 425                IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
 426               ieee80211_is_mgmt(hdr->frame_control))) {
 427                 /*
 428                  * hwaccel has no need for preallocated room for CCMP
 429                  * header or MIC fields
 430                  */
 431                 return 0;
 432         }
 433
 434         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 435         len = skb->len - hdrlen;
 436
 437         if (info->control.hw_key)
 438                 tail = 0;
 439         else
 440                 tail = mic_len;
 441
 442         if (WARN_ON(skb_tailroom(skb) < tail ||
 443                     skb_headroom(skb) < IEEE80211_CCMP_HDR_LEN))
 444                 return -1;
 445
 446         pos = skb_push(skb, IEEE80211_CCMP_HDR_LEN);
 447         memmove(pos, pos + IEEE80211_CCMP_HDR_LEN, hdrlen);
 448
 449         /* the HW only needs room for the IV, but not the actual IV */
 450         if (info->control.hw_key &&
 451             (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 452                 return 0;
 453
 454         hdr = (struct ieee80211_hdr *) pos;
 455         pos += hdrlen;
 456
 457         pn64 = atomic64_inc_return(&key->conf.tx_pn);
 458
 459         pn[5] = pn64;
 460         pn[4] = pn64 >> 8;
 461         pn[3] = pn64 >> 16;
 462         pn[2] = pn64 >> 24;
 463         pn[1] = pn64 >> 32;
 464         pn[0] = pn64 >> 40;
 465
 466         ccmp_pn2hdr(pos, pn, key->conf.keyidx);
 467
 468         /* hwaccel - with software CCMP header */
 469         if (info->control.hw_key)
 470                 return 0;
 471
 472         pos += IEEE80211_CCMP_HDR_LEN;
 473         ccmp_special_blocks(skb, pn, b_0, aad);
 474         return ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, b_0, aad, pos, len,
 475                                          skb_put(skb, mic_len));
 476 }
 477
 478
 479 ieee80211_tx_result
 480 ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx,
 481                               unsigned int mic_len)
 482 {
 483         struct sk_buff *skb;
 484
 485         ieee80211_tx_set_protected(tx);
 486
 487         skb_queue_walk(&tx->skbs, skb) {
 488                 if (ccmp_encrypt_skb(tx, skb, mic_len) < 0)
 489                         return TX_DROP;
 490         }
 491
 492         return TX_CONTINUE;
 493 }
 494
 495
 496 ieee80211_rx_result
 497 ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx,
 498                               unsigned int mic_len)
 499 {
 500         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 501         int hdrlen;
 502         struct ieee80211_key *key = rx->key;
 503         struct sk_buff *skb = rx->skb;
 504         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 505         u8 pn[IEEE80211_CCMP_PN_LEN];
 506         int data_len;
 507         int queue;
 508
 509         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 510
 511         if (!ieee80211_is_data(hdr->frame_control) &&
 512             !ieee80211_is_robust_mgmt_frame(skb))
 513                 return RX_CONTINUE;
 514
 515         if (status->flag & RX_FLAG_DECRYPTED) {
 516                 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_CCMP_HDR_LEN))
 517                         return RX_DROP_UNUSABLE;
 518                 if (status->flag & RX_FLAG_MIC_STRIPPED)
 519                         mic_len = 0;
 520         } else {
 521                 if (skb_linearize(rx->skb))
 522                         return RX_DROP_UNUSABLE;
 523         }
 524
 525         data_len = skb->len - hdrlen - IEEE80211_CCMP_HDR_LEN - mic_len;
 526         if (!rx->sta || data_len < 0)
 527                 return RX_DROP_UNUSABLE;
 528
 529         if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
 530                 int res;
 531
 532                 ccmp_hdr2pn(pn, skb->data + hdrlen);
 533
 534                 queue = rx->security_idx;
 535
 536                 res = memcmp(pn, key->u.ccmp.rx_pn[queue],
 537                              IEEE80211_CCMP_PN_LEN);
 538                 if (res < 0 ||
 539                     (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
 540                         key->u.ccmp.replays++;
 541                         return RX_DROP_UNUSABLE;
 542                 }
 543
 544                 if (!(status->flag & RX_FLAG_DECRYPTED)) {
 545                         u8 aad[2 * AES_BLOCK_SIZE];
 546                         u8 b_0[AES_BLOCK_SIZE];
 547                         /* hardware didn't decrypt/verify MIC */
 548                         ccmp_special_blocks(skb, pn, b_0, aad);
 549
 550                         if (ieee80211_aes_ccm_decrypt(
 551                                     key->u.ccmp.tfm, b_0, aad,
 552                                     skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN,
 553                                     data_len,
 554                                     skb->data + skb->len - mic_len))
 555                                 return RX_DROP_UNUSABLE;
 556                 }
 557
 558                 memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN);
 559         }
 560
 561         /* Remove CCMP header and MIC */
 562         if (pskb_trim(skb, skb->len - mic_len))
 563                 return RX_DROP_UNUSABLE;
 564         memmove(skb->data + IEEE80211_CCMP_HDR_LEN, skb->data, hdrlen);
 565         skb_pull(skb, IEEE80211_CCMP_HDR_LEN);
 566
 567         return RX_CONTINUE;
 568 }
 569
 570 static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad)
 571 {
 572         __le16 mask_fc;
 573         u8 qos_tid;
 574         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 575
 576         memcpy(j_0, hdr->addr2, ETH_ALEN);
 577         memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN);
 578         j_0[13] = 0;
 579         j_0[14] = 0;
 580         j_0[AES_BLOCK_SIZE - 1] = 0x01;
 581
 582         /* AAD (extra authenticate-only data) / masked 802.11 header
 583          * FC | A1 | A2 | A3 | SC | [A4] | [QC]
 584          */
 585         put_unaligned_be16(ieee80211_hdrlen(hdr->frame_control) - 2, &aad[0]);
 586         /* Mask FC: zero subtype b4 b5 b6 (if not mgmt)
 587          * Retry, PwrMgt, MoreData; set Protected
 588          */
 589         mask_fc = hdr->frame_control;
 590         mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
 591                                 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
 592         if (!ieee80211_is_mgmt(hdr->frame_control))
 593                 mask_fc &= ~cpu_to_le16(0x0070);
 594         mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
 595
 596         put_unaligned(mask_fc, (__le16 *)&aad[2]);
 597         memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
 598
 599         /* Mask Seq#, leave Frag# */
 600         aad[22] = *((u8 *)&hdr->seq_ctrl) & 0x0f;
 601         aad[23] = 0;
 602
 603         if (ieee80211_is_data_qos(hdr->frame_control))
 604                 qos_tid = *ieee80211_get_qos_ctl(hdr) &
 605                         IEEE80211_QOS_CTL_TID_MASK;
 606         else
 607                 qos_tid = 0;
 608
 609         if (ieee80211_has_a4(hdr->frame_control)) {
 610                 memcpy(&aad[24], hdr->addr4, ETH_ALEN);
 611                 aad[30] = qos_tid;
 612                 aad[31] = 0;
 613         } else {
 614                 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
 615                 aad[24] = qos_tid;
 616         }
 617 }
 618
 619 static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id)
 620 {
 621         hdr[0] = pn[5];
 622         hdr[1] = pn[4];
 623         hdr[2] = 0;
 624         hdr[3] = 0x20 | (key_id << 6);
 625         hdr[4] = pn[3];
 626         hdr[5] = pn[2];
 627         hdr[6] = pn[1];
 628         hdr[7] = pn[0];
 629 }
 630
 631 static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr)
 632 {
 633         pn[0] = hdr[7];
 634         pn[1] = hdr[6];
 635         pn[2] = hdr[5];
 636         pn[3] = hdr[4];
 637         pn[4] = hdr[1];
 638         pn[5] = hdr[0];
 639 }
 640
 641 static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
 642 {
 643         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 644         struct ieee80211_key *key = tx->key;
 645         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 646         int hdrlen, len, tail;
 647         u8 *pos;
 648         u8 pn[6];
 649         u64 pn64;
 650         u8 aad[GCM_AAD_LEN];
 651         u8 j_0[AES_BLOCK_SIZE];
 652
 653         if (info->control.hw_key &&
 654             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 655             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 656             !((info->control.hw_key->flags &
 657                IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
 658               ieee80211_is_mgmt(hdr->frame_control))) {
 659                 /* hwaccel has no need for preallocated room for GCMP
 660                  * header or MIC fields
 661                  */
 662                 return 0;
 663         }
 664
 665         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 666         len = skb->len - hdrlen;
 667
 668         if (info->control.hw_key)
 669                 tail = 0;
 670         else
 671                 tail = IEEE80211_GCMP_MIC_LEN;
 672
 673         if (WARN_ON(skb_tailroom(skb) < tail ||
 674                     skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN))
 675                 return -1;
 676
 677         pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN);
 678         memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen);
 679         skb_set_network_header(skb, skb_network_offset(skb) +
 680                                     IEEE80211_GCMP_HDR_LEN);
 681
 682         /* the HW only needs room for the IV, but not the actual IV */
 683         if (info->control.hw_key &&
 684             (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 685                 return 0;
 686
 687         hdr = (struct ieee80211_hdr *)pos;
 688         pos += hdrlen;
 689
 690         pn64 = atomic64_inc_return(&key->conf.tx_pn);
 691
 692         pn[5] = pn64;
 693         pn[4] = pn64 >> 8;
 694         pn[3] = pn64 >> 16;
 695         pn[2] = pn64 >> 24;
 696         pn[1] = pn64 >> 32;
 697         pn[0] = pn64 >> 40;
 698
 699         gcmp_pn2hdr(pos, pn, key->conf.keyidx);
 700
 701         /* hwaccel - with software GCMP header */
 702         if (info->control.hw_key)
 703                 return 0;
 704
 705         pos += IEEE80211_GCMP_HDR_LEN;
 706         gcmp_special_blocks(skb, pn, j_0, aad);
 707         return ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len,
 708                                          skb_put(skb, IEEE80211_GCMP_MIC_LEN));
 709 }
 710
 711 ieee80211_tx_result
 712 ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx)
 713 {
 714         struct sk_buff *skb;
 715
 716         ieee80211_tx_set_protected(tx);
 717
 718         skb_queue_walk(&tx->skbs, skb) {
 719                 if (gcmp_encrypt_skb(tx, skb) < 0)
 720                         return TX_DROP;
 721         }
 722
 723         return TX_CONTINUE;
 724 }
 725
 726 ieee80211_rx_result
 727 ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
 728 {
 729         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 730         int hdrlen;
 731         struct ieee80211_key *key = rx->key;
 732         struct sk_buff *skb = rx->skb;
 733         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 734         u8 pn[IEEE80211_GCMP_PN_LEN];
 735         int data_len, queue, mic_len = IEEE80211_GCMP_MIC_LEN;
 736
 737         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 738
 739         if (!ieee80211_is_data(hdr->frame_control) &&
 740             !ieee80211_is_robust_mgmt_frame(skb))
 741                 return RX_CONTINUE;
 742
 743         if (status->flag & RX_FLAG_DECRYPTED) {
 744                 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN))
 745                         return RX_DROP_UNUSABLE;
 746                 if (status->flag & RX_FLAG_MIC_STRIPPED)
 747                         mic_len = 0;
 748         } else {
 749                 if (skb_linearize(rx->skb))
 750                         return RX_DROP_UNUSABLE;
 751         }
 752
 753         data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN - mic_len;
 754         if (!rx->sta || data_len < 0)
 755                 return RX_DROP_UNUSABLE;
 756
 757         if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
 758                 int res;
 759
 760                 gcmp_hdr2pn(pn, skb->data + hdrlen);
 761
 762                 queue = rx->security_idx;
 763
 764                 res = memcmp(pn, key->u.gcmp.rx_pn[queue],
 765                              IEEE80211_GCMP_PN_LEN);
 766                 if (res < 0 ||
 767                     (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
 768                         key->u.gcmp.replays++;
 769                         return RX_DROP_UNUSABLE;
 770                 }
 771
 772                 if (!(status->flag & RX_FLAG_DECRYPTED)) {
 773                         u8 aad[2 * AES_BLOCK_SIZE];
 774                         u8 j_0[AES_BLOCK_SIZE];
 775                         /* hardware didn't decrypt/verify MIC */
 776                         gcmp_special_blocks(skb, pn, j_0, aad);
 777
 778                         if (ieee80211_aes_gcm_decrypt(
 779                                     key->u.gcmp.tfm, j_0, aad,
 780                                     skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN,
 781                                     data_len,
 782                                     skb->data + skb->len -
 783                                     IEEE80211_GCMP_MIC_LEN))
 784                                 return RX_DROP_UNUSABLE;
 785                 }
 786
 787                 memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN);
 788         }
 789
 790         /* Remove GCMP header and MIC */
 791         if (pskb_trim(skb, skb->len - mic_len))
 792                 return RX_DROP_UNUSABLE;
 793         memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen);
 794         skb_pull(skb, IEEE80211_GCMP_HDR_LEN);
 795
 796         return RX_CONTINUE;
 797 }
 798
 799 static ieee80211_tx_result
 800 ieee80211_crypto_cs_encrypt(struct ieee80211_tx_data *tx,
 801                             struct sk_buff *skb)
 802 {
 803         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 804         struct ieee80211_key *key = tx->key;
 805         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 806         int hdrlen;
 807         u8 *pos, iv_len = key->conf.iv_len;
 808
 809         if (info->control.hw_key &&
 810             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
 811                 /* hwaccel has no need for preallocated head room */
 812                 return TX_CONTINUE;
 813         }
 814
 815         if (unlikely(skb_headroom(skb) < iv_len &&
 816                      pskb_expand_head(skb, iv_len, 0, GFP_ATOMIC)))
 817                 return TX_DROP;
 818
 819         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 820
 821         pos = skb_push(skb, iv_len);
 822         memmove(pos, pos + iv_len, hdrlen);
 823
 824         return TX_CONTINUE;
 825 }
 826
 827 static inline int ieee80211_crypto_cs_pn_compare(u8 *pn1, u8 *pn2, int len)
 828 {
 829         int i;
 830
 831         /* pn is little endian */
 832         for (i = len - 1; i >= 0; i--) {
 833                 if (pn1[i] < pn2[i])
 834                         return -1;
 835                 else if (pn1[i] > pn2[i])
 836                         return 1;
 837         }
 838
 839         return 0;
 840 }
 841
 842 static ieee80211_rx_result
 843 ieee80211_crypto_cs_decrypt(struct ieee80211_rx_data *rx)
 844 {
 845         struct ieee80211_key *key = rx->key;
 846         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 847         const struct ieee80211_cipher_scheme *cs = NULL;
 848         int hdrlen = ieee80211_hdrlen(hdr->frame_control);
 849         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 850         int data_len;
 851         u8 *rx_pn;
 852         u8 *skb_pn;
 853         u8 qos_tid;
 854
 855         if (!rx->sta || !rx->sta->cipher_scheme ||
 856             !(status->flag & RX_FLAG_DECRYPTED))
 857                 return RX_DROP_UNUSABLE;
 858
 859         if (!ieee80211_is_data(hdr->frame_control))
 860                 return RX_CONTINUE;
 861
 862         cs = rx->sta->cipher_scheme;
 863
 864         data_len = rx->skb->len - hdrlen - cs->hdr_len;
 865
 866         if (data_len < 0)
 867                 return RX_DROP_UNUSABLE;
 868
 869         if (ieee80211_is_data_qos(hdr->frame_control))
 870                 qos_tid = *ieee80211_get_qos_ctl(hdr) &
 871                                 IEEE80211_QOS_CTL_TID_MASK;
 872         else
 873                 qos_tid = 0;
 874
 875         if (skb_linearize(rx->skb))
 876                 return RX_DROP_UNUSABLE;
 877
 878         hdr = (struct ieee80211_hdr *)rx->skb->data;
 879
 880         rx_pn = key->u.gen.rx_pn[qos_tid];
 881         skb_pn = rx->skb->data + hdrlen + cs->pn_off;
 882
 883         if (ieee80211_crypto_cs_pn_compare(skb_pn, rx_pn, cs->pn_len) <= 0)
 884                 return RX_DROP_UNUSABLE;
 885
 886         memcpy(rx_pn, skb_pn, cs->pn_len);
 887
 888         /* remove security header and MIC */
 889         if (pskb_trim(rx->skb, rx->skb->len - cs->mic_len))
 890                 return RX_DROP_UNUSABLE;
 891
 892         memmove(rx->skb->data + cs->hdr_len, rx->skb->data, hdrlen);
 893         skb_pull(rx->skb, cs->hdr_len);
 894
 895         return RX_CONTINUE;
 896 }
 897
 898 static void bip_aad(struct sk_buff *skb, u8 *aad)
 899 {
 900         __le16 mask_fc;
 901         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 902
 903         /* BIP AAD: FC(masked) || A1 || A2 || A3 */
 904
 905         /* FC type/subtype */
 906         /* Mask FC Retry, PwrMgt, MoreData flags to zero */
 907         mask_fc = hdr->frame_control;
 908         mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM |
 909                                 IEEE80211_FCTL_MOREDATA);
 910         put_unaligned(mask_fc, (__le16 *) &aad[0]);
 911         /* A1 || A2 || A3 */
 912         memcpy(aad + 2, &hdr->addr1, 3 * ETH_ALEN);
 913 }
 914
 915
 916 static inline void bip_ipn_set64(u8 *d, u64 pn)
 917 {
 918         *d++ = pn;
 919         *d++ = pn >> 8;
 920         *d++ = pn >> 16;
 921         *d++ = pn >> 24;
 922         *d++ = pn >> 32;
 923         *d = pn >> 40;
 924 }
 925
 926 static inline void bip_ipn_swap(u8 *d, const u8 *s)
 927 {
 928         *d++ = s[5];
 929         *d++ = s[4];
 930         *d++ = s[3];
 931         *d++ = s[2];
 932         *d++ = s[1];
 933         *d = s[0];
 934 }
 935
 936
 937 ieee80211_tx_result
 938 ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
 939 {
 940         struct sk_buff *skb;
 941         struct ieee80211_tx_info *info;
 942         struct ieee80211_key *key = tx->key;
 943         struct ieee80211_mmie *mmie;
 944         u8 aad[20];
 945         u64 pn64;
 946
 947         if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
 948                 return TX_DROP;
 949
 950         skb = skb_peek(&tx->skbs);
 951
 952         info = IEEE80211_SKB_CB(skb);
 953
 954         if (info->control.hw_key)
 955                 return TX_CONTINUE;
 956
 957         if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
 958                 return TX_DROP;
 959
 960         mmie = skb_put(skb, sizeof(*mmie));
 961         mmie->element_id = WLAN_EID_MMIE;
 962         mmie->length = sizeof(*mmie) - 2;
 963         mmie->key_id = cpu_to_le16(key->conf.keyidx);
 964
 965         /* PN = PN + 1 */
 966         pn64 = atomic64_inc_return(&key->conf.tx_pn);
 967
 968         bip_ipn_set64(mmie->sequence_number, pn64);
 969
 970         bip_aad(skb, aad);
 971
 972         /*
 973          * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
 974          */
 975         ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
 976                            skb->data + 24, skb->len - 24, mmie->mic);
 977
 978         return TX_CONTINUE;
 979 }
 980
 981 ieee80211_tx_result
 982 ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx)
 983 {
 984         struct sk_buff *skb;
 985         struct ieee80211_tx_info *info;
 986         struct ieee80211_key *key = tx->key;
 987         struct ieee80211_mmie_16 *mmie;
 988         u8 aad[20];
 989         u64 pn64;
 990
 991         if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
 992                 return TX_DROP;
 993
 994         skb = skb_peek(&tx->skbs);
 995
 996         info = IEEE80211_SKB_CB(skb);
 997
 998         if (info->control.hw_key)
 999                 return TX_CONTINUE;
1000
1001         if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
1002                 return TX_DROP;
1003
1004         mmie = skb_put(skb, sizeof(*mmie));
1005         mmie->element_id = WLAN_EID_MMIE;
1006         mmie->length = sizeof(*mmie) - 2;
1007         mmie->key_id = cpu_to_le16(key->conf.keyidx);
1008
1009         /* PN = PN + 1 */
1010         pn64 = atomic64_inc_return(&key->conf.tx_pn);
1011
1012         bip_ipn_set64(mmie->sequence_number, pn64);
1013
1014         bip_aad(skb, aad);
1015
1016         /* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128)
1017          */
1018         ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1019                                skb->data + 24, skb->len - 24, mmie->mic);
1020
1021         return TX_CONTINUE;
1022 }
1023
1024 ieee80211_rx_result
1025 ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
1026 {
1027         struct sk_buff *skb = rx->skb;
1028         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1029         struct ieee80211_key *key = rx->key;
1030         struct ieee80211_mmie *mmie;
1031         u8 aad[20], mic[8], ipn[6];
1032         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1033
1034         if (!ieee80211_is_mgmt(hdr->frame_control))
1035                 return RX_CONTINUE;
1036
1037         /* management frames are already linear */
1038
1039         if (skb->len < 24 + sizeof(*mmie))
1040                 return RX_DROP_UNUSABLE;
1041
1042         mmie = (struct ieee80211_mmie *)
1043                 (skb->data + skb->len - sizeof(*mmie));
1044         if (mmie->element_id != WLAN_EID_MMIE ||
1045             mmie->length != sizeof(*mmie) - 2)
1046                 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1047
1048         bip_ipn_swap(ipn, mmie->sequence_number);
1049
1050         if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1051                 key->u.aes_cmac.replays++;
1052                 return RX_DROP_UNUSABLE;
1053         }
1054
1055         if (!(status->flag & RX_FLAG_DECRYPTED)) {
1056                 /* hardware didn't decrypt/verify MIC */
1057                 bip_aad(skb, aad);
1058                 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
1059                                    skb->data + 24, skb->len - 24, mic);
1060                 if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
1061                         key->u.aes_cmac.icverrors++;
1062                         return RX_DROP_UNUSABLE;
1063                 }
1064         }
1065
1066         memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1067
1068         /* Remove MMIE */
1069         skb_trim(skb, skb->len - sizeof(*mmie));
1070
1071         return RX_CONTINUE;
1072 }
1073
1074 ieee80211_rx_result
1075 ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx)
1076 {
1077         struct sk_buff *skb = rx->skb;
1078         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1079         struct ieee80211_key *key = rx->key;
1080         struct ieee80211_mmie_16 *mmie;
1081         u8 aad[20], mic[16], ipn[6];
1082         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1083
1084         if (!ieee80211_is_mgmt(hdr->frame_control))
1085                 return RX_CONTINUE;
1086
1087         /* management frames are already linear */
1088
1089         if (skb->len < 24 + sizeof(*mmie))
1090                 return RX_DROP_UNUSABLE;
1091
1092         mmie = (struct ieee80211_mmie_16 *)
1093                 (skb->data + skb->len - sizeof(*mmie));
1094         if (mmie->element_id != WLAN_EID_MMIE ||
1095             mmie->length != sizeof(*mmie) - 2)
1096                 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1097
1098         bip_ipn_swap(ipn, mmie->sequence_number);
1099
1100         if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1101                 key->u.aes_cmac.replays++;
1102                 return RX_DROP_UNUSABLE;
1103         }
1104
1105         if (!(status->flag & RX_FLAG_DECRYPTED)) {
1106                 /* hardware didn't decrypt/verify MIC */
1107                 bip_aad(skb, aad);
1108                 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1109                                        skb->data + 24, skb->len - 24, mic);
1110                 if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
1111                         key->u.aes_cmac.icverrors++;
1112                         return RX_DROP_UNUSABLE;
1113                 }
1114         }
1115
1116         memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1117
1118         /* Remove MMIE */
1119         skb_trim(skb, skb->len - sizeof(*mmie));
1120
1121         return RX_CONTINUE;
1122 }
1123
1124 ieee80211_tx_result
1125 ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx)
1126 {
1127         struct sk_buff *skb;
1128         struct ieee80211_tx_info *info;
1129         struct ieee80211_key *key = tx->key;
1130         struct ieee80211_mmie_16 *mmie;
1131         struct ieee80211_hdr *hdr;
1132         u8 aad[GMAC_AAD_LEN];
1133         u64 pn64;
1134         u8 nonce[GMAC_NONCE_LEN];
1135
1136         if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
1137                 return TX_DROP;
1138
1139         skb = skb_peek(&tx->skbs);
1140
1141         info = IEEE80211_SKB_CB(skb);
1142
1143         if (info->control.hw_key)
1144                 return TX_CONTINUE;
1145
1146         if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
1147                 return TX_DROP;
1148
1149         mmie = skb_put(skb, sizeof(*mmie));
1150         mmie->element_id = WLAN_EID_MMIE;
1151         mmie->length = sizeof(*mmie) - 2;
1152         mmie->key_id = cpu_to_le16(key->conf.keyidx);
1153
1154         /* PN = PN + 1 */
1155         pn64 = atomic64_inc_return(&key->conf.tx_pn);
1156
1157         bip_ipn_set64(mmie->sequence_number, pn64);
1158
1159         bip_aad(skb, aad);
1160
1161         hdr = (struct ieee80211_hdr *)skb->data;
1162         memcpy(nonce, hdr->addr2, ETH_ALEN);
1163         bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number);
1164
1165         /* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */
1166         if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1167                                skb->data + 24, skb->len - 24, mmie->mic) < 0)
1168                 return TX_DROP;
1169
1170         return TX_CONTINUE;
1171 }
1172
1173 ieee80211_rx_result
1174 ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx)
1175 {
1176         struct sk_buff *skb = rx->skb;
1177         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1178         struct ieee80211_key *key = rx->key;
1179         struct ieee80211_mmie_16 *mmie;
1180         u8 aad[GMAC_AAD_LEN], mic[GMAC_MIC_LEN], ipn[6], nonce[GMAC_NONCE_LEN];
1181         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1182
1183         if (!ieee80211_is_mgmt(hdr->frame_control))
1184                 return RX_CONTINUE;
1185
1186         /* management frames are already linear */
1187
1188         if (skb->len < 24 + sizeof(*mmie))
1189                 return RX_DROP_UNUSABLE;
1190
1191         mmie = (struct ieee80211_mmie_16 *)
1192                 (skb->data + skb->len - sizeof(*mmie));
1193         if (mmie->element_id != WLAN_EID_MMIE ||
1194             mmie->length != sizeof(*mmie) - 2)
1195                 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1196
1197         bip_ipn_swap(ipn, mmie->sequence_number);
1198
1199         if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) {
1200                 key->u.aes_gmac.replays++;
1201                 return RX_DROP_UNUSABLE;
1202         }
1203
1204         if (!(status->flag & RX_FLAG_DECRYPTED)) {
1205                 /* hardware didn't decrypt/verify MIC */
1206                 bip_aad(skb, aad);
1207
1208                 memcpy(nonce, hdr->addr2, ETH_ALEN);
1209                 memcpy(nonce + ETH_ALEN, ipn, 6);
1210
1211                 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1212                                        skb->data + 24, skb->len - 24,
1213                                        mic) < 0 ||
1214                     crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
1215                         key->u.aes_gmac.icverrors++;
1216                         return RX_DROP_UNUSABLE;
1217                 }
1218         }
1219
1220         memcpy(key->u.aes_gmac.rx_pn, ipn, 6);
1221
1222         /* Remove MMIE */
1223         skb_trim(skb, skb->len - sizeof(*mmie));
1224
1225         return RX_CONTINUE;
1226 }
1227
1228 ieee80211_tx_result
1229 ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx)
1230 {
1231         struct sk_buff *skb;
1232         struct ieee80211_tx_info *info = NULL;
1233         ieee80211_tx_result res;
1234
1235         skb_queue_walk(&tx->skbs, skb) {
1236                 info  = IEEE80211_SKB_CB(skb);
1237
1238                 /* handle hw-only algorithm */
1239                 if (!info->control.hw_key)
1240                         return TX_DROP;
1241
1242                 if (tx->key->flags & KEY_FLAG_CIPHER_SCHEME) {
1243                         res = ieee80211_crypto_cs_encrypt(tx, skb);
1244                         if (res != TX_CONTINUE)
1245                                 return res;
1246                 }
1247         }
1248
1249         ieee80211_tx_set_protected(tx);
1250
1251         return TX_CONTINUE;
1252 }
1253
1254 ieee80211_rx_result
1255 ieee80211_crypto_hw_decrypt(struct ieee80211_rx_data *rx)
1256 {
1257         if (rx->sta && rx->sta->cipher_scheme)
1258                 return ieee80211_crypto_cs_decrypt(rx);
1259
1260         return RX_DROP_UNUSABLE;
1261 }