net/mac80211/wpa.c

   1 /*
   2  * Copyright 2002-2004, Instant802 Networks, Inc.
   3  * Copyright 2008, Jouni Malinen <j@w1.fi>
   4  * Copyright (C) 2016 Intel Deutschland GmbH
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 #include <linux/netdevice.h>
  12 #include <linux/types.h>
  13 #include <linux/skbuff.h>
  14 #include <linux/compiler.h>
  15 #include <linux/ieee80211.h>
  16 #include <linux/gfp.h>
  17 #include <asm/unaligned.h>
  18 #include <net/mac80211.h>
  19 #include <crypto/aes.h>
  20 #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                 /* hwaccel - with no need for SW-generated MMIC */
  64                 return TX_CONTINUE;
  65         }
  66
  67         tail = MICHAEL_MIC_LEN;
  68         if (!info->control.hw_key)
  69                 tail += IEEE80211_TKIP_ICV_LEN;
  70
  71         if (WARN(skb_tailroom(skb) < tail ||
  72                  skb_headroom(skb) < IEEE80211_TKIP_IV_LEN,
  73                  "mmic: not enough head/tail (%d/%d,%d/%d)\n",
  74                  skb_headroom(skb), IEEE80211_TKIP_IV_LEN,
  75                  skb_tailroom(skb), tail))
  76                 return TX_DROP;
  77
  78         key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY];
  79         mic = skb_put(skb, MICHAEL_MIC_LEN);
  80         michael_mic(key, hdr, data, data_len, mic);
  81         if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE))
  82                 mic[0]++;
  83
  84         return TX_CONTINUE;
  85 }
  86
  87
  88 ieee80211_rx_result
  89 ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
  90 {
  91         u8 *data, *key = NULL;
  92         size_t data_len;
  93         unsigned int hdrlen;
  94         u8 mic[MICHAEL_MIC_LEN];
  95         struct sk_buff *skb = rx->skb;
  96         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  97         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  98
  99         /*
 100          * it makes no sense to check for MIC errors on anything other
 101          * than data frames.
 102          */
 103         if (!ieee80211_is_data_present(hdr->frame_control))
 104                 return RX_CONTINUE;
 105
 106         /*
 107          * No way to verify the MIC if the hardware stripped it or
 108          * the IV with the key index. In this case we have solely rely
 109          * on the driver to set RX_FLAG_MMIC_ERROR in the event of a
 110          * MIC failure report.
 111          */
 112         if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) {
 113                 if (status->flag & RX_FLAG_MMIC_ERROR)
 114                         goto mic_fail_no_key;
 115
 116                 if (!(status->flag & RX_FLAG_IV_STRIPPED) && rx->key &&
 117                     rx->key->conf.cipher == WLAN_CIPHER_SUITE_TKIP)
 118                         goto update_iv;
 119
 120                 return RX_CONTINUE;
 121         }
 122
 123         /*
 124          * Some hardware seems to generate Michael MIC failure reports; even
 125          * though, the frame was not encrypted with TKIP and therefore has no
 126          * MIC. Ignore the flag them to avoid triggering countermeasures.
 127          */
 128         if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
 129             !(status->flag & RX_FLAG_DECRYPTED))
 130                 return RX_CONTINUE;
 131
 132         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) {
 133                 /*
 134                  * APs with pairwise keys should never receive Michael MIC
 135                  * errors for non-zero keyidx because these are reserved for
 136                  * group keys and only the AP is sending real multicast
 137                  * frames in the BSS.
 138                  */
 139                 return RX_DROP_UNUSABLE;
 140         }
 141
 142         if (status->flag & RX_FLAG_MMIC_ERROR)
 143                 goto mic_fail;
 144
 145         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 146         if (skb->len < hdrlen + MICHAEL_MIC_LEN)
 147                 return RX_DROP_UNUSABLE;
 148
 149         if (skb_linearize(rx->skb))
 150                 return RX_DROP_UNUSABLE;
 151         hdr = (void *)skb->data;
 152
 153         data = skb->data + hdrlen;
 154         data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;
 155         key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY];
 156         michael_mic(key, hdr, data, data_len, mic);
 157         if (crypto_memneq(mic, data + data_len, MICHAEL_MIC_LEN))
 158                 goto mic_fail;
 159
 160         /* remove Michael MIC from payload */
 161         skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
 162
 163 update_iv:
 164         /* update IV in key information to be able to detect replays */
 165         rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip_iv32;
 166         rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip_iv16;
 167
 168         return RX_CONTINUE;
 169
 170 mic_fail:
 171         rx->key->u.tkip.mic_failures++;
 172
 173 mic_fail_no_key:
 174         /*
 175          * In some cases the key can be unset - e.g. a multicast packet, in
 176          * a driver that supports HW encryption. Send up the key idx only if
 177          * the key is set.
 178          */
 179         cfg80211_michael_mic_failure(rx->sdata->dev, hdr->addr2,
 180                                      is_multicast_ether_addr(hdr->addr1) ?
 181                                      NL80211_KEYTYPE_GROUP :
 182                                      NL80211_KEYTYPE_PAIRWISE,
 183                                      rx->key ? rx->key->conf.keyidx : -1,
 184                                      NULL, GFP_ATOMIC);
 185         return RX_DROP_UNUSABLE;
 186 }
 187
 188 static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
 189 {
 190         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 191         struct ieee80211_key *key = tx->key;
 192         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 193         unsigned int hdrlen;
 194         int len, tail;
 195         u64 pn;
 196         u8 *pos;
 197
 198         if (info->control.hw_key &&
 199             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 200             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
 201                 /* hwaccel - with no need for software-generated IV */
 202                 return 0;
 203         }
 204
 205         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 206         len = skb->len - hdrlen;
 207
 208         if (info->control.hw_key)
 209                 tail = 0;
 210         else
 211                 tail = IEEE80211_TKIP_ICV_LEN;
 212
 213         if (WARN_ON(skb_tailroom(skb) < tail ||
 214                     skb_headroom(skb) < IEEE80211_TKIP_IV_LEN))
 215                 return -1;
 216
 217         pos = skb_push(skb, IEEE80211_TKIP_IV_LEN);
 218         memmove(pos, pos + IEEE80211_TKIP_IV_LEN, hdrlen);
 219         pos += hdrlen;
 220
 221         /* the HW only needs room for the IV, but not the actual IV */
 222         if (info->control.hw_key &&
 223             (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 224                 return 0;
 225
 226         /* Increase IV for the frame */
 227         pn = atomic64_inc_return(&key->conf.tx_pn);
 228         pos = ieee80211_tkip_add_iv(pos, &key->conf, pn);
 229
 230         /* hwaccel - with software IV */
 231         if (info->control.hw_key)
 232                 return 0;
 233
 234         /* Add room for ICV */
 235         skb_put(skb, IEEE80211_TKIP_ICV_LEN);
 236
 237         return ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,
 238                                            key, skb, pos, len);
 239 }
 240
 241
 242 ieee80211_tx_result
 243 ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
 244 {
 245         struct sk_buff *skb;
 246
 247         ieee80211_tx_set_protected(tx);
 248
 249         skb_queue_walk(&tx->skbs, skb) {
 250                 if (tkip_encrypt_skb(tx, skb) < 0)
 251                         return TX_DROP;
 252         }
 253
 254         return TX_CONTINUE;
 255 }
 256
 257
 258 ieee80211_rx_result
 259 ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
 260 {
 261         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 262         int hdrlen, res, hwaccel = 0;
 263         struct ieee80211_key *key = rx->key;
 264         struct sk_buff *skb = rx->skb;
 265         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 266
 267         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 268
 269         if (!ieee80211_is_data(hdr->frame_control))
 270                 return RX_CONTINUE;
 271
 272         if (!rx->sta || skb->len - hdrlen < 12)
 273                 return RX_DROP_UNUSABLE;
 274
 275         /* it may be possible to optimize this a bit more */
 276         if (skb_linearize(rx->skb))
 277                 return RX_DROP_UNUSABLE;
 278         hdr = (void *)skb->data;
 279
 280         /*
 281          * Let TKIP code verify IV, but skip decryption.
 282          * In the case where hardware checks the IV as well,
 283          * we don't even get here, see ieee80211_rx_h_decrypt()
 284          */
 285         if (status->flag & RX_FLAG_DECRYPTED)
 286                 hwaccel = 1;
 287
 288         res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm,
 289                                           key, skb->data + hdrlen,
 290                                           skb->len - hdrlen, rx->sta->sta.addr,
 291                                           hdr->addr1, hwaccel, rx->security_idx,
 292                                           &rx->tkip_iv32,
 293                                           &rx->tkip_iv16);
 294         if (res != TKIP_DECRYPT_OK)
 295                 return RX_DROP_UNUSABLE;
 296
 297         /* Trim ICV */
 298         if (!(status->flag & RX_FLAG_ICV_STRIPPED))
 299                 skb_trim(skb, skb->len - IEEE80211_TKIP_ICV_LEN);
 300
 301         /* Remove IV */
 302         memmove(skb->data + IEEE80211_TKIP_IV_LEN, skb->data, hdrlen);
 303         skb_pull(skb, IEEE80211_TKIP_IV_LEN);
 304
 305         return RX_CONTINUE;
 306 }
 307
 308
 309 static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad)
 310 {
 311         __le16 mask_fc;
 312         int a4_included, mgmt;
 313         u8 qos_tid;
 314         u16 len_a;
 315         unsigned int hdrlen;
 316         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 317
 318         /*
 319          * Mask FC: zero subtype b4 b5 b6 (if not mgmt)
 320          * Retry, PwrMgt, MoreData; set Protected
 321          */
 322         mgmt = ieee80211_is_mgmt(hdr->frame_control);
 323         mask_fc = hdr->frame_control;
 324         mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
 325                                 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
 326         if (!mgmt)
 327                 mask_fc &= ~cpu_to_le16(0x0070);
 328         mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
 329
 330         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 331         len_a = hdrlen - 2;
 332         a4_included = ieee80211_has_a4(hdr->frame_control);
 333
 334         if (ieee80211_is_data_qos(hdr->frame_control))
 335                 qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
 336         else
 337                 qos_tid = 0;
 338
 339         /* In CCM, the initial vectors (IV) used for CTR mode encryption and CBC
 340          * mode authentication are not allowed to collide, yet both are derived
 341          * from this vector b_0. We only set L := 1 here to indicate that the
 342          * data size can be represented in (L+1) bytes. The CCM layer will take
 343          * care of storing the data length in the top (L+1) bytes and setting
 344          * and clearing the other bits as is required to derive the two IVs.
 345          */
 346         b_0[0] = 0x1;
 347
 348         /* Nonce: Nonce Flags | A2 | PN
 349          * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7)
 350          */
 351         b_0[1] = qos_tid | (mgmt << 4);
 352         memcpy(&b_0[2], hdr->addr2, ETH_ALEN);
 353         memcpy(&b_0[8], pn, IEEE80211_CCMP_PN_LEN);
 354
 355         /* AAD (extra authenticate-only data) / masked 802.11 header
 356          * FC | A1 | A2 | A3 | SC | [A4] | [QC] */
 357         put_unaligned_be16(len_a, &aad[0]);
 358         put_unaligned(mask_fc, (__le16 *)&aad[2]);
 359         memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
 360
 361         /* Mask Seq#, leave Frag# */
 362         aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;
 363         aad[23] = 0;
 364
 365         if (a4_included) {
 366                 memcpy(&aad[24], hdr->addr4, ETH_ALEN);
 367                 aad[30] = qos_tid;
 368                 aad[31] = 0;
 369         } else {
 370                 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
 371                 aad[24] = qos_tid;
 372         }
 373 }
 374
 375
 376 static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)
 377 {
 378         hdr[0] = pn[5];
 379         hdr[1] = pn[4];
 380         hdr[2] = 0;
 381         hdr[3] = 0x20 | (key_id << 6);
 382         hdr[4] = pn[3];
 383         hdr[5] = pn[2];
 384         hdr[6] = pn[1];
 385         hdr[7] = pn[0];
 386 }
 387
 388
 389 static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr)
 390 {
 391         pn[0] = hdr[7];
 392         pn[1] = hdr[6];
 393         pn[2] = hdr[5];
 394         pn[3] = hdr[4];
 395         pn[4] = hdr[1];
 396         pn[5] = hdr[0];
 397 }
 398
 399
 400 static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb,
 401                             unsigned int mic_len)
 402 {
 403         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 404         struct ieee80211_key *key = tx->key;
 405         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 406         int hdrlen, len, tail;
 407         u8 *pos;
 408         u8 pn[6];
 409         u64 pn64;
 410         u8 aad[CCM_AAD_LEN];
 411         u8 b_0[AES_BLOCK_SIZE];
 412
 413         if (info->control.hw_key &&
 414             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 415             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 416             !((info->control.hw_key->flags &
 417                IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
 418               ieee80211_is_mgmt(hdr->frame_control))) {
 419                 /*
 420                  * hwaccel has no need for preallocated room for CCMP
 421                  * header or MIC fields
 422                  */
 423                 return 0;
 424         }
 425
 426         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 427         len = skb->len - hdrlen;
 428
 429         if (info->control.hw_key)
 430                 tail = 0;
 431         else
 432                 tail = mic_len;
 433
 434         if (WARN_ON(skb_tailroom(skb) < tail ||
 435                     skb_headroom(skb) < IEEE80211_CCMP_HDR_LEN))
 436                 return -1;
 437
 438         pos = skb_push(skb, IEEE80211_CCMP_HDR_LEN);
 439         memmove(pos, pos + IEEE80211_CCMP_HDR_LEN, hdrlen);
 440
 441         /* the HW only needs room for the IV, but not the actual IV */
 442         if (info->control.hw_key &&
 443             (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 444                 return 0;
 445
 446         hdr = (struct ieee80211_hdr *) pos;
 447         pos += hdrlen;
 448
 449         pn64 = atomic64_inc_return(&key->conf.tx_pn);
 450
 451         pn[5] = pn64;
 452         pn[4] = pn64 >> 8;
 453         pn[3] = pn64 >> 16;
 454         pn[2] = pn64 >> 24;
 455         pn[1] = pn64 >> 32;
 456         pn[0] = pn64 >> 40;
 457
 458         ccmp_pn2hdr(pos, pn, key->conf.keyidx);
 459
 460         /* hwaccel - with software CCMP header */
 461         if (info->control.hw_key)
 462                 return 0;
 463
 464         pos += IEEE80211_CCMP_HDR_LEN;
 465         ccmp_special_blocks(skb, pn, b_0, aad);
 466         return ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, b_0, aad, pos, len,
 467                                          skb_put(skb, mic_len), mic_len);
 468 }
 469
 470
 471 ieee80211_tx_result
 472 ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx,
 473                               unsigned int mic_len)
 474 {
 475         struct sk_buff *skb;
 476
 477         ieee80211_tx_set_protected(tx);
 478
 479         skb_queue_walk(&tx->skbs, skb) {
 480                 if (ccmp_encrypt_skb(tx, skb, mic_len) < 0)
 481                         return TX_DROP;
 482         }
 483
 484         return TX_CONTINUE;
 485 }
 486
 487
 488 ieee80211_rx_result
 489 ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx,
 490                               unsigned int mic_len)
 491 {
 492         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 493         int hdrlen;
 494         struct ieee80211_key *key = rx->key;
 495         struct sk_buff *skb = rx->skb;
 496         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 497         u8 pn[IEEE80211_CCMP_PN_LEN];
 498         int data_len;
 499         int queue;
 500
 501         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 502
 503         if (!ieee80211_is_data(hdr->frame_control) &&
 504             !ieee80211_is_robust_mgmt_frame(skb))
 505                 return RX_CONTINUE;
 506
 507         if (status->flag & RX_FLAG_DECRYPTED) {
 508                 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_CCMP_HDR_LEN))
 509                         return RX_DROP_UNUSABLE;
 510                 if (status->flag & RX_FLAG_MIC_STRIPPED)
 511                         mic_len = 0;
 512         } else {
 513                 if (skb_linearize(rx->skb))
 514                         return RX_DROP_UNUSABLE;
 515         }
 516
 517         data_len = skb->len - hdrlen - IEEE80211_CCMP_HDR_LEN - mic_len;
 518         if (!rx->sta || data_len < 0)
 519                 return RX_DROP_UNUSABLE;
 520
 521         if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
 522                 int res;
 523
 524                 ccmp_hdr2pn(pn, skb->data + hdrlen);
 525
 526                 queue = rx->security_idx;
 527
 528                 res = memcmp(pn, key->u.ccmp.rx_pn[queue],
 529                              IEEE80211_CCMP_PN_LEN);
 530                 if (res < 0 ||
 531                     (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
 532                         key->u.ccmp.replays++;
 533                         return RX_DROP_UNUSABLE;
 534                 }
 535
 536                 if (!(status->flag & RX_FLAG_DECRYPTED)) {
 537                         u8 aad[2 * AES_BLOCK_SIZE];
 538                         u8 b_0[AES_BLOCK_SIZE];
 539                         /* hardware didn't decrypt/verify MIC */
 540                         ccmp_special_blocks(skb, pn, b_0, aad);
 541
 542                         if (ieee80211_aes_ccm_decrypt(
 543                                     key->u.ccmp.tfm, b_0, aad,
 544                                     skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN,
 545                                     data_len,
 546                                     skb->data + skb->len - mic_len, mic_len))
 547                                 return RX_DROP_UNUSABLE;
 548                 }
 549
 550                 memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN);
 551         }
 552
 553         /* Remove CCMP header and MIC */
 554         if (pskb_trim(skb, skb->len - mic_len))
 555                 return RX_DROP_UNUSABLE;
 556         memmove(skb->data + IEEE80211_CCMP_HDR_LEN, skb->data, hdrlen);
 557         skb_pull(skb, IEEE80211_CCMP_HDR_LEN);
 558
 559         return RX_CONTINUE;
 560 }
 561
 562 static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad)
 563 {
 564         __le16 mask_fc;
 565         u8 qos_tid;
 566         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 567
 568         memcpy(j_0, hdr->addr2, ETH_ALEN);
 569         memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN);
 570         j_0[13] = 0;
 571         j_0[14] = 0;
 572         j_0[AES_BLOCK_SIZE - 1] = 0x01;
 573
 574         /* AAD (extra authenticate-only data) / masked 802.11 header
 575          * FC | A1 | A2 | A3 | SC | [A4] | [QC]
 576          */
 577         put_unaligned_be16(ieee80211_hdrlen(hdr->frame_control) - 2, &aad[0]);
 578         /* Mask FC: zero subtype b4 b5 b6 (if not mgmt)
 579          * Retry, PwrMgt, MoreData; set Protected
 580          */
 581         mask_fc = hdr->frame_control;
 582         mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
 583                                 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
 584         if (!ieee80211_is_mgmt(hdr->frame_control))
 585                 mask_fc &= ~cpu_to_le16(0x0070);
 586         mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
 587
 588         put_unaligned(mask_fc, (__le16 *)&aad[2]);
 589         memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
 590
 591         /* Mask Seq#, leave Frag# */
 592         aad[22] = *((u8 *)&hdr->seq_ctrl) & 0x0f;
 593         aad[23] = 0;
 594
 595         if (ieee80211_is_data_qos(hdr->frame_control))
 596                 qos_tid = *ieee80211_get_qos_ctl(hdr) &
 597                         IEEE80211_QOS_CTL_TID_MASK;
 598         else
 599                 qos_tid = 0;
 600
 601         if (ieee80211_has_a4(hdr->frame_control)) {
 602                 memcpy(&aad[24], hdr->addr4, ETH_ALEN);
 603                 aad[30] = qos_tid;
 604                 aad[31] = 0;
 605         } else {
 606                 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
 607                 aad[24] = qos_tid;
 608         }
 609 }
 610
 611 static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id)
 612 {
 613         hdr[0] = pn[5];
 614         hdr[1] = pn[4];
 615         hdr[2] = 0;
 616         hdr[3] = 0x20 | (key_id << 6);
 617         hdr[4] = pn[3];
 618         hdr[5] = pn[2];
 619         hdr[6] = pn[1];
 620         hdr[7] = pn[0];
 621 }
 622
 623 static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr)
 624 {
 625         pn[0] = hdr[7];
 626         pn[1] = hdr[6];
 627         pn[2] = hdr[5];
 628         pn[3] = hdr[4];
 629         pn[4] = hdr[1];
 630         pn[5] = hdr[0];
 631 }
 632
 633 static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
 634 {
 635         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 636         struct ieee80211_key *key = tx->key;
 637         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 638         int hdrlen, len, tail;
 639         u8 *pos;
 640         u8 pn[6];
 641         u64 pn64;
 642         u8 aad[GCM_AAD_LEN];
 643         u8 j_0[AES_BLOCK_SIZE];
 644
 645         if (info->control.hw_key &&
 646             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 647             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 648             !((info->control.hw_key->flags &
 649                IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
 650               ieee80211_is_mgmt(hdr->frame_control))) {
 651                 /* hwaccel has no need for preallocated room for GCMP
 652                  * header or MIC fields
 653                  */
 654                 return 0;
 655         }
 656
 657         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 658         len = skb->len - hdrlen;
 659
 660         if (info->control.hw_key)
 661                 tail = 0;
 662         else
 663                 tail = IEEE80211_GCMP_MIC_LEN;
 664
 665         if (WARN_ON(skb_tailroom(skb) < tail ||
 666                     skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN))
 667                 return -1;
 668
 669         pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN);
 670         memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen);
 671         skb_set_network_header(skb, skb_network_offset(skb) +
 672                                     IEEE80211_GCMP_HDR_LEN);
 673
 674         /* the HW only needs room for the IV, but not the actual IV */
 675         if (info->control.hw_key &&
 676             (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 677                 return 0;
 678
 679         hdr = (struct ieee80211_hdr *)pos;
 680         pos += hdrlen;
 681
 682         pn64 = atomic64_inc_return(&key->conf.tx_pn);
 683
 684         pn[5] = pn64;
 685         pn[4] = pn64 >> 8;
 686         pn[3] = pn64 >> 16;
 687         pn[2] = pn64 >> 24;
 688         pn[1] = pn64 >> 32;
 689         pn[0] = pn64 >> 40;
 690
 691         gcmp_pn2hdr(pos, pn, key->conf.keyidx);
 692
 693         /* hwaccel - with software GCMP header */
 694         if (info->control.hw_key)
 695                 return 0;
 696
 697         pos += IEEE80211_GCMP_HDR_LEN;
 698         gcmp_special_blocks(skb, pn, j_0, aad);
 699         return ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len,
 700                                          skb_put(skb, IEEE80211_GCMP_MIC_LEN));
 701 }
 702
 703 ieee80211_tx_result
 704 ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx)
 705 {
 706         struct sk_buff *skb;
 707
 708         ieee80211_tx_set_protected(tx);
 709
 710         skb_queue_walk(&tx->skbs, skb) {
 711                 if (gcmp_encrypt_skb(tx, skb) < 0)
 712                         return TX_DROP;
 713         }
 714
 715         return TX_CONTINUE;
 716 }
 717
 718 ieee80211_rx_result
 719 ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
 720 {
 721         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 722         int hdrlen;
 723         struct ieee80211_key *key = rx->key;
 724         struct sk_buff *skb = rx->skb;
 725         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 726         u8 pn[IEEE80211_GCMP_PN_LEN];
 727         int data_len, queue, mic_len = IEEE80211_GCMP_MIC_LEN;
 728
 729         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 730
 731         if (!ieee80211_is_data(hdr->frame_control) &&
 732             !ieee80211_is_robust_mgmt_frame(skb))
 733                 return RX_CONTINUE;
 734
 735         if (status->flag & RX_FLAG_DECRYPTED) {
 736                 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN))
 737                         return RX_DROP_UNUSABLE;
 738                 if (status->flag & RX_FLAG_MIC_STRIPPED)
 739                         mic_len = 0;
 740         } else {
 741                 if (skb_linearize(rx->skb))
 742                         return RX_DROP_UNUSABLE;
 743         }
 744
 745         data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN - mic_len;
 746         if (!rx->sta || data_len < 0)
 747                 return RX_DROP_UNUSABLE;
 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_UNUSABLE;
 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
 770                         if (ieee80211_aes_gcm_decrypt(
 771                                     key->u.gcmp.tfm, j_0, aad,
 772                                     skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN,
 773                                     data_len,
 774                                     skb->data + skb->len -
 775                                     IEEE80211_GCMP_MIC_LEN))
 776                                 return RX_DROP_UNUSABLE;
 777                 }
 778
 779                 memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN);
 780         }
 781
 782         /* Remove GCMP header and MIC */
 783         if (pskb_trim(skb, skb->len - mic_len))
 784                 return RX_DROP_UNUSABLE;
 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 ieee80211_tx_result
 792 ieee80211_crypto_cs_encrypt(struct ieee80211_tx_data *tx,
 793                             struct sk_buff *skb)
 794 {
 795         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 796         struct ieee80211_key *key = tx->key;
 797         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 798         int hdrlen;
 799         u8 *pos, iv_len = key->conf.iv_len;
 800
 801         if (info->control.hw_key &&
 802             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
 803                 /* hwaccel has no need for preallocated head room */
 804                 return TX_CONTINUE;
 805         }
 806
 807         if (unlikely(skb_headroom(skb) < iv_len &&
 808                      pskb_expand_head(skb, iv_len, 0, GFP_ATOMIC)))
 809                 return TX_DROP;
 810
 811         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 812
 813         pos = skb_push(skb, iv_len);
 814         memmove(pos, pos + iv_len, hdrlen);
 815
 816         return TX_CONTINUE;
 817 }
 818
 819 static inline int ieee80211_crypto_cs_pn_compare(u8 *pn1, u8 *pn2, int len)
 820 {
 821         int i;
 822
 823         /* pn is little endian */
 824         for (i = len - 1; i >= 0; i--) {
 825                 if (pn1[i] < pn2[i])
 826                         return -1;
 827                 else if (pn1[i] > pn2[i])
 828                         return 1;
 829         }
 830
 831         return 0;
 832 }
 833
 834 static ieee80211_rx_result
 835 ieee80211_crypto_cs_decrypt(struct ieee80211_rx_data *rx)
 836 {
 837         struct ieee80211_key *key = rx->key;
 838         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 839         const struct ieee80211_cipher_scheme *cs = NULL;
 840         int hdrlen = ieee80211_hdrlen(hdr->frame_control);
 841         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 842         int data_len;
 843         u8 *rx_pn;
 844         u8 *skb_pn;
 845         u8 qos_tid;
 846
 847         if (!rx->sta || !rx->sta->cipher_scheme ||
 848             !(status->flag & RX_FLAG_DECRYPTED))
 849                 return RX_DROP_UNUSABLE;
 850
 851         if (!ieee80211_is_data(hdr->frame_control))
 852                 return RX_CONTINUE;
 853
 854         cs = rx->sta->cipher_scheme;
 855
 856         data_len = rx->skb->len - hdrlen - cs->hdr_len;
 857
 858         if (data_len < 0)
 859                 return RX_DROP_UNUSABLE;
 860
 861         if (ieee80211_is_data_qos(hdr->frame_control))
 862                 qos_tid = *ieee80211_get_qos_ctl(hdr) &
 863                                 IEEE80211_QOS_CTL_TID_MASK;
 864         else
 865                 qos_tid = 0;
 866
 867         if (skb_linearize(rx->skb))
 868                 return RX_DROP_UNUSABLE;
 869
 870         hdr = (struct ieee80211_hdr *)rx->skb->data;
 871
 872         rx_pn = key->u.gen.rx_pn[qos_tid];
 873         skb_pn = rx->skb->data + hdrlen + cs->pn_off;
 874
 875         if (ieee80211_crypto_cs_pn_compare(skb_pn, rx_pn, cs->pn_len) <= 0)
 876                 return RX_DROP_UNUSABLE;
 877
 878         memcpy(rx_pn, skb_pn, cs->pn_len);
 879
 880         /* remove security header and MIC */
 881         if (pskb_trim(rx->skb, rx->skb->len - cs->mic_len))
 882                 return RX_DROP_UNUSABLE;
 883
 884         memmove(rx->skb->data + cs->hdr_len, rx->skb->data, hdrlen);
 885         skb_pull(rx->skb, cs->hdr_len);
 886
 887         return RX_CONTINUE;
 888 }
 889
 890 static void bip_aad(struct sk_buff *skb, u8 *aad)
 891 {
 892         __le16 mask_fc;
 893         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 894
 895         /* BIP AAD: FC(masked) || A1 || A2 || A3 */
 896
 897         /* FC type/subtype */
 898         /* Mask FC Retry, PwrMgt, MoreData flags to zero */
 899         mask_fc = hdr->frame_control;
 900         mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM |
 901                                 IEEE80211_FCTL_MOREDATA);
 902         put_unaligned(mask_fc, (__le16 *) &aad[0]);
 903         /* A1 || A2 || A3 */
 904         memcpy(aad + 2, &hdr->addr1, 3 * ETH_ALEN);
 905 }
 906
 907
 908 static inline void bip_ipn_set64(u8 *d, u64 pn)
 909 {
 910         *d++ = pn;
 911         *d++ = pn >> 8;
 912         *d++ = pn >> 16;
 913         *d++ = pn >> 24;
 914         *d++ = pn >> 32;
 915         *d = pn >> 40;
 916 }
 917
 918 static inline void bip_ipn_swap(u8 *d, const u8 *s)
 919 {
 920         *d++ = s[5];
 921         *d++ = s[4];
 922         *d++ = s[3];
 923         *d++ = s[2];
 924         *d++ = s[1];
 925         *d = s[0];
 926 }
 927
 928
 929 ieee80211_tx_result
 930 ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
 931 {
 932         struct sk_buff *skb;
 933         struct ieee80211_tx_info *info;
 934         struct ieee80211_key *key = tx->key;
 935         struct ieee80211_mmie *mmie;
 936         u8 aad[20];
 937         u64 pn64;
 938
 939         if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
 940                 return TX_DROP;
 941
 942         skb = skb_peek(&tx->skbs);
 943
 944         info = IEEE80211_SKB_CB(skb);
 945
 946         if (info->control.hw_key)
 947                 return TX_CONTINUE;
 948
 949         if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
 950                 return TX_DROP;
 951
 952         mmie = skb_put(skb, sizeof(*mmie));
 953         mmie->element_id = WLAN_EID_MMIE;
 954         mmie->length = sizeof(*mmie) - 2;
 955         mmie->key_id = cpu_to_le16(key->conf.keyidx);
 956
 957         /* PN = PN + 1 */
 958         pn64 = atomic64_inc_return(&key->conf.tx_pn);
 959
 960         bip_ipn_set64(mmie->sequence_number, pn64);
 961
 962         bip_aad(skb, aad);
 963
 964         /*
 965          * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
 966          */
 967         ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
 968                            skb->data + 24, skb->len - 24, mmie->mic);
 969
 970         return TX_CONTINUE;
 971 }
 972
 973 ieee80211_tx_result
 974 ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx)
 975 {
 976         struct sk_buff *skb;
 977         struct ieee80211_tx_info *info;
 978         struct ieee80211_key *key = tx->key;
 979         struct ieee80211_mmie_16 *mmie;
 980         u8 aad[20];
 981         u64 pn64;
 982
 983         if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
 984                 return TX_DROP;
 985
 986         skb = skb_peek(&tx->skbs);
 987
 988         info = IEEE80211_SKB_CB(skb);
 989
 990         if (info->control.hw_key)
 991                 return TX_CONTINUE;
 992
 993         if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
 994                 return TX_DROP;
 995
 996         mmie = skb_put(skb, sizeof(*mmie));
 997         mmie->element_id = WLAN_EID_MMIE;
 998         mmie->length = sizeof(*mmie) - 2;
 999         mmie->key_id = cpu_to_le16(key->conf.keyidx);
1000
1001         /* PN = PN + 1 */
1002         pn64 = atomic64_inc_return(&key->conf.tx_pn);
1003
1004         bip_ipn_set64(mmie->sequence_number, pn64);
1005
1006         bip_aad(skb, aad);
1007
1008         /* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128)
1009          */
1010         ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1011                                skb->data + 24, skb->len - 24, mmie->mic);
1012
1013         return TX_CONTINUE;
1014 }
1015
1016 ieee80211_rx_result
1017 ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
1018 {
1019         struct sk_buff *skb = rx->skb;
1020         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1021         struct ieee80211_key *key = rx->key;
1022         struct ieee80211_mmie *mmie;
1023         u8 aad[20], mic[8], ipn[6];
1024         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1025
1026         if (!ieee80211_is_mgmt(hdr->frame_control))
1027                 return RX_CONTINUE;
1028
1029         /* management frames are already linear */
1030
1031         if (skb->len < 24 + sizeof(*mmie))
1032                 return RX_DROP_UNUSABLE;
1033
1034         mmie = (struct ieee80211_mmie *)
1035                 (skb->data + skb->len - sizeof(*mmie));
1036         if (mmie->element_id != WLAN_EID_MMIE ||
1037             mmie->length != sizeof(*mmie) - 2)
1038                 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1039
1040         bip_ipn_swap(ipn, mmie->sequence_number);
1041
1042         if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1043                 key->u.aes_cmac.replays++;
1044                 return RX_DROP_UNUSABLE;
1045         }
1046
1047         if (!(status->flag & RX_FLAG_DECRYPTED)) {
1048                 /* hardware didn't decrypt/verify MIC */
1049                 bip_aad(skb, aad);
1050                 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
1051                                    skb->data + 24, skb->len - 24, mic);
1052                 if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
1053                         key->u.aes_cmac.icverrors++;
1054                         return RX_DROP_UNUSABLE;
1055                 }
1056         }
1057
1058         memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1059
1060         /* Remove MMIE */
1061         skb_trim(skb, skb->len - sizeof(*mmie));
1062
1063         return RX_CONTINUE;
1064 }
1065
1066 ieee80211_rx_result
1067 ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx)
1068 {
1069         struct sk_buff *skb = rx->skb;
1070         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1071         struct ieee80211_key *key = rx->key;
1072         struct ieee80211_mmie_16 *mmie;
1073         u8 aad[20], mic[16], ipn[6];
1074         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1075
1076         if (!ieee80211_is_mgmt(hdr->frame_control))
1077                 return RX_CONTINUE;
1078
1079         /* management frames are already linear */
1080
1081         if (skb->len < 24 + sizeof(*mmie))
1082                 return RX_DROP_UNUSABLE;
1083
1084         mmie = (struct ieee80211_mmie_16 *)
1085                 (skb->data + skb->len - sizeof(*mmie));
1086         if (mmie->element_id != WLAN_EID_MMIE ||
1087             mmie->length != sizeof(*mmie) - 2)
1088                 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1089
1090         bip_ipn_swap(ipn, mmie->sequence_number);
1091
1092         if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1093                 key->u.aes_cmac.replays++;
1094                 return RX_DROP_UNUSABLE;
1095         }
1096
1097         if (!(status->flag & RX_FLAG_DECRYPTED)) {
1098                 /* hardware didn't decrypt/verify MIC */
1099                 bip_aad(skb, aad);
1100                 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1101                                        skb->data + 24, skb->len - 24, mic);
1102                 if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
1103                         key->u.aes_cmac.icverrors++;
1104                         return RX_DROP_UNUSABLE;
1105                 }
1106         }
1107
1108         memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1109
1110         /* Remove MMIE */
1111         skb_trim(skb, skb->len - sizeof(*mmie));
1112
1113         return RX_CONTINUE;
1114 }
1115
1116 ieee80211_tx_result
1117 ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx)
1118 {
1119         struct sk_buff *skb;
1120         struct ieee80211_tx_info *info;
1121         struct ieee80211_key *key = tx->key;
1122         struct ieee80211_mmie_16 *mmie;
1123         struct ieee80211_hdr *hdr;
1124         u8 aad[GMAC_AAD_LEN];
1125         u64 pn64;
1126         u8 nonce[GMAC_NONCE_LEN];
1127
1128         if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
1129                 return TX_DROP;
1130
1131         skb = skb_peek(&tx->skbs);
1132
1133         info = IEEE80211_SKB_CB(skb);
1134
1135         if (info->control.hw_key)
1136                 return TX_CONTINUE;
1137
1138         if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
1139                 return TX_DROP;
1140
1141         mmie = skb_put(skb, sizeof(*mmie));
1142         mmie->element_id = WLAN_EID_MMIE;
1143         mmie->length = sizeof(*mmie) - 2;
1144         mmie->key_id = cpu_to_le16(key->conf.keyidx);
1145
1146         /* PN = PN + 1 */
1147         pn64 = atomic64_inc_return(&key->conf.tx_pn);
1148
1149         bip_ipn_set64(mmie->sequence_number, pn64);
1150
1151         bip_aad(skb, aad);
1152
1153         hdr = (struct ieee80211_hdr *)skb->data;
1154         memcpy(nonce, hdr->addr2, ETH_ALEN);
1155         bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number);
1156
1157         /* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */
1158         if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1159                                skb->data + 24, skb->len - 24, mmie->mic) < 0)
1160                 return TX_DROP;
1161
1162         return TX_CONTINUE;
1163 }
1164
1165 ieee80211_rx_result
1166 ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx)
1167 {
1168         struct sk_buff *skb = rx->skb;
1169         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1170         struct ieee80211_key *key = rx->key;
1171         struct ieee80211_mmie_16 *mmie;
1172         u8 aad[GMAC_AAD_LEN], mic[GMAC_MIC_LEN], ipn[6], nonce[GMAC_NONCE_LEN];
1173         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1174
1175         if (!ieee80211_is_mgmt(hdr->frame_control))
1176                 return RX_CONTINUE;
1177
1178         /* management frames are already linear */
1179
1180         if (skb->len < 24 + sizeof(*mmie))
1181                 return RX_DROP_UNUSABLE;
1182
1183         mmie = (struct ieee80211_mmie_16 *)
1184                 (skb->data + skb->len - sizeof(*mmie));
1185         if (mmie->element_id != WLAN_EID_MMIE ||
1186             mmie->length != sizeof(*mmie) - 2)
1187                 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1188
1189         bip_ipn_swap(ipn, mmie->sequence_number);
1190
1191         if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) {
1192                 key->u.aes_gmac.replays++;
1193                 return RX_DROP_UNUSABLE;
1194         }
1195
1196         if (!(status->flag & RX_FLAG_DECRYPTED)) {
1197                 /* hardware didn't decrypt/verify MIC */
1198                 bip_aad(skb, aad);
1199
1200                 memcpy(nonce, hdr->addr2, ETH_ALEN);
1201                 memcpy(nonce + ETH_ALEN, ipn, 6);
1202
1203                 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1204                                        skb->data + 24, skb->len - 24,
1205                                        mic) < 0 ||
1206                     crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
1207                         key->u.aes_gmac.icverrors++;
1208                         return RX_DROP_UNUSABLE;
1209                 }
1210         }
1211
1212         memcpy(key->u.aes_gmac.rx_pn, ipn, 6);
1213
1214         /* Remove MMIE */
1215         skb_trim(skb, skb->len - sizeof(*mmie));
1216
1217         return RX_CONTINUE;
1218 }
1219
1220 ieee80211_tx_result
1221 ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx)
1222 {
1223         struct sk_buff *skb;
1224         struct ieee80211_tx_info *info = NULL;
1225         ieee80211_tx_result res;
1226
1227         skb_queue_walk(&tx->skbs, skb) {
1228                 info  = IEEE80211_SKB_CB(skb);
1229
1230                 /* handle hw-only algorithm */
1231                 if (!info->control.hw_key)
1232                         return TX_DROP;
1233
1234                 if (tx->key->flags & KEY_FLAG_CIPHER_SCHEME) {
1235                         res = ieee80211_crypto_cs_encrypt(tx, skb);
1236                         if (res != TX_CONTINUE)
1237                                 return res;
1238                 }
1239         }
1240
1241         ieee80211_tx_set_protected(tx);
1242
1243         return TX_CONTINUE;
1244 }
1245
1246 ieee80211_rx_result
1247 ieee80211_crypto_hw_decrypt(struct ieee80211_rx_data *rx)
1248 {
1249         if (rx->sta && rx->sta->cipher_scheme)
1250                 return ieee80211_crypto_cs_decrypt(rx);
1251
1252         return RX_DROP_UNUSABLE;
1253 }