net/mac80211/wpa.c

   1 /*
   2  * Copyright 2002-2004, Instant802 Networks, Inc.
   3  * Copyright 2008, Jouni Malinen <j@w1.fi>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  */
   9
  10 #include <linux/netdevice.h>
  11 #include <linux/types.h>
  12 #include <linux/skbuff.h>
  13 #include <linux/compiler.h>
  14 #include <linux/ieee80211.h>
  15 #include <linux/gfp.h>
  16 #include <asm/unaligned.h>
  17 #include <net/mac80211.h>
  18 #include <crypto/aes.h>
  19
  20 #include "ieee80211_i.h"
  21 #include "michael.h"
  22 #include "tkip.h"
  23 #include "aes_ccm.h"
  24 #include "aes_cmac.h"
  25 #include "aes_gmac.h"
  26 #include "aes_gcm.h"
  27 #include "wpa.h"
  28
  29 ieee80211_tx_result
  30 ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
  31 {
  32         u8 *data, *key, *mic;
  33         size_t data_len;
  34         unsigned int hdrlen;
  35         struct ieee80211_hdr *hdr;
  36         struct sk_buff *skb = tx->skb;
  37         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  38         int tail;
  39
  40         hdr = (struct ieee80211_hdr *)skb->data;
  41         if (!tx->key || tx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
  42             skb->len < 24 || !ieee80211_is_data_present(hdr->frame_control))
  43                 return TX_CONTINUE;
  44
  45         hdrlen = ieee80211_hdrlen(hdr->frame_control);
  46         if (skb->len < hdrlen)
  47                 return TX_DROP;
  48
  49         data = skb->data + hdrlen;
  50         data_len = skb->len - hdrlen;
  51
  52         if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) {
  53                 /* Need to use software crypto for the test */
  54                 info->control.hw_key = NULL;
  55         }
  56
  57         if (info->control.hw_key &&
  58             (info->flags & IEEE80211_TX_CTL_DONTFRAG ||
  59              tx->local->ops->set_frag_threshold) &&
  60             !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) {
  61                 /* hwaccel - with no need for SW-generated MMIC */
  62                 return TX_CONTINUE;
  63         }
  64
  65         tail = MICHAEL_MIC_LEN;
  66         if (!info->control.hw_key)
  67                 tail += IEEE80211_TKIP_ICV_LEN;
  68
  69         if (WARN(skb_tailroom(skb) < tail ||
  70                  skb_headroom(skb) < IEEE80211_TKIP_IV_LEN,
  71                  "mmic: not enough head/tail (%d/%d,%d/%d)\n",
  72                  skb_headroom(skb), IEEE80211_TKIP_IV_LEN,
  73                  skb_tailroom(skb), tail))
  74                 return TX_DROP;
  75
  76         key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY];
  77         mic = skb_put(skb, MICHAEL_MIC_LEN);
  78         michael_mic(key, hdr, data, data_len, mic);
  79         if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE))
  80                 mic[0]++;
  81
  82         return TX_CONTINUE;
  83 }
  84
  85
  86 ieee80211_rx_result
  87 ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
  88 {
  89         u8 *data, *key = NULL;
  90         size_t data_len;
  91         unsigned int hdrlen;
  92         u8 mic[MICHAEL_MIC_LEN];
  93         struct sk_buff *skb = rx->skb;
  94         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  95         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  96
  97         /*
  98          * it makes no sense to check for MIC errors on anything other
  99          * than data frames.
 100          */
 101         if (!ieee80211_is_data_present(hdr->frame_control))
 102                 return RX_CONTINUE;
 103
 104         /*
 105          * No way to verify the MIC if the hardware stripped it or
 106          * the IV with the key index. In this case we have solely rely
 107          * on the driver to set RX_FLAG_MMIC_ERROR in the event of a
 108          * MIC failure report.
 109          */
 110         if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) {
 111                 if (status->flag & RX_FLAG_MMIC_ERROR)
 112                         goto mic_fail_no_key;
 113
 114                 if (!(status->flag & RX_FLAG_IV_STRIPPED) && rx->key &&
 115                     rx->key->conf.cipher == WLAN_CIPHER_SUITE_TKIP)
 116                         goto update_iv;
 117
 118                 return RX_CONTINUE;
 119         }
 120
 121         /*
 122          * Some hardware seems to generate Michael MIC failure reports; even
 123          * though, the frame was not encrypted with TKIP and therefore has no
 124          * MIC. Ignore the flag them to avoid triggering countermeasures.
 125          */
 126         if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
 127             !(status->flag & RX_FLAG_DECRYPTED))
 128                 return RX_CONTINUE;
 129
 130         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) {
 131                 /*
 132                  * APs with pairwise keys should never receive Michael MIC
 133                  * errors for non-zero keyidx because these are reserved for
 134                  * group keys and only the AP is sending real multicast
 135                  * frames in the BSS.
 136                  */
 137                 return RX_DROP_UNUSABLE;
 138         }
 139
 140         if (status->flag & RX_FLAG_MMIC_ERROR)
 141                 goto mic_fail;
 142
 143         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 144         if (skb->len < hdrlen + MICHAEL_MIC_LEN)
 145                 return RX_DROP_UNUSABLE;
 146
 147         if (skb_linearize(rx->skb))
 148                 return RX_DROP_UNUSABLE;
 149         hdr = (void *)skb->data;
 150
 151         data = skb->data + hdrlen;
 152         data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;
 153         key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY];
 154         michael_mic(key, hdr, data, data_len, mic);
 155         if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0)
 156                 goto mic_fail;
 157
 158         /* remove Michael MIC from payload */
 159         skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
 160
 161 update_iv:
 162         /* update IV in key information to be able to detect replays */
 163         rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip_iv32;
 164         rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip_iv16;
 165
 166         return RX_CONTINUE;
 167
 168 mic_fail:
 169         rx->key->u.tkip.mic_failures++;
 170
 171 mic_fail_no_key:
 172         /*
 173          * In some cases the key can be unset - e.g. a multicast packet, in
 174          * a driver that supports HW encryption. Send up the key idx only if
 175          * the key is set.
 176          */
 177         mac80211_ev_michael_mic_failure(rx->sdata,
 178                                         rx->key ? rx->key->conf.keyidx : -1,
 179                                         (void *) skb->data, NULL, GFP_ATOMIC);
 180         return RX_DROP_UNUSABLE;
 181 }
 182
 183
 184 static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
 185 {
 186         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 187         struct ieee80211_key *key = tx->key;
 188         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 189         unsigned int hdrlen;
 190         int len, tail;
 191         u8 *pos;
 192
 193         if (info->control.hw_key &&
 194             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 195             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
 196                 /* hwaccel - with no need for software-generated IV */
 197                 return 0;
 198         }
 199
 200         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 201         len = skb->len - hdrlen;
 202
 203         if (info->control.hw_key)
 204                 tail = 0;
 205         else
 206                 tail = IEEE80211_TKIP_ICV_LEN;
 207
 208         if (WARN_ON(skb_tailroom(skb) < tail ||
 209                     skb_headroom(skb) < IEEE80211_TKIP_IV_LEN))
 210                 return -1;
 211
 212         pos = skb_push(skb, IEEE80211_TKIP_IV_LEN);
 213         memmove(pos, pos + IEEE80211_TKIP_IV_LEN, hdrlen);
 214         pos += hdrlen;
 215
 216         /* the HW only needs room for the IV, but not the actual IV */
 217         if (info->control.hw_key &&
 218             (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 219                 return 0;
 220
 221         /* Increase IV for the frame */
 222         spin_lock(&key->u.tkip.txlock);
 223         key->u.tkip.tx.iv16++;
 224         if (key->u.tkip.tx.iv16 == 0)
 225                 key->u.tkip.tx.iv32++;
 226         pos = ieee80211_tkip_add_iv(pos, key);
 227         spin_unlock(&key->u.tkip.txlock);
 228
 229         /* hwaccel - with software IV */
 230         if (info->control.hw_key)
 231                 return 0;
 232
 233         /* Add room for ICV */
 234         skb_put(skb, IEEE80211_TKIP_ICV_LEN);
 235
 236         return ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,
 237                                            key, skb, pos, len);
 238 }
 239
 240
 241 ieee80211_tx_result
 242 ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
 243 {
 244         struct sk_buff *skb;
 245
 246         ieee80211_tx_set_protected(tx);
 247
 248         skb_queue_walk(&tx->skbs, skb) {
 249                 if (tkip_encrypt_skb(tx, skb) < 0)
 250                         return TX_DROP;
 251         }
 252
 253         return TX_CONTINUE;
 254 }
 255
 256
 257 ieee80211_rx_result
 258 ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
 259 {
 260         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 261         int hdrlen, res, hwaccel = 0;
 262         struct ieee80211_key *key = rx->key;
 263         struct sk_buff *skb = rx->skb;
 264         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 265
 266         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 267
 268         if (!ieee80211_is_data(hdr->frame_control))
 269                 return RX_CONTINUE;
 270
 271         if (!rx->sta || skb->len - hdrlen < 12)
 272                 return RX_DROP_UNUSABLE;
 273
 274         /* it may be possible to optimize this a bit more */
 275         if (skb_linearize(rx->skb))
 276                 return RX_DROP_UNUSABLE;
 277         hdr = (void *)skb->data;
 278
 279         /*
 280          * Let TKIP code verify IV, but skip decryption.
 281          * In the case where hardware checks the IV as well,
 282          * we don't even get here, see ieee80211_rx_h_decrypt()
 283          */
 284         if (status->flag & RX_FLAG_DECRYPTED)
 285                 hwaccel = 1;
 286
 287         res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm,
 288                                           key, skb->data + hdrlen,
 289                                           skb->len - hdrlen, rx->sta->sta.addr,
 290                                           hdr->addr1, hwaccel, rx->security_idx,
 291                                           &rx->tkip_iv32,
 292                                           &rx->tkip_iv16);
 293         if (res != TKIP_DECRYPT_OK)
 294                 return RX_DROP_UNUSABLE;
 295
 296         /* Trim ICV */
 297         skb_trim(skb, skb->len - IEEE80211_TKIP_ICV_LEN);
 298
 299         /* Remove IV */
 300         memmove(skb->data + IEEE80211_TKIP_IV_LEN, skb->data, hdrlen);
 301         skb_pull(skb, IEEE80211_TKIP_IV_LEN);
 302
 303         return RX_CONTINUE;
 304 }
 305
 306
 307 static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad)
 308 {
 309         __le16 mask_fc;
 310         int a4_included, mgmt;
 311         u8 qos_tid;
 312         u16 len_a;
 313         unsigned int hdrlen;
 314         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 315
 316         /*
 317          * Mask FC: zero subtype b4 b5 b6 (if not mgmt)
 318          * Retry, PwrMgt, MoreData; set Protected
 319          */
 320         mgmt = ieee80211_is_mgmt(hdr->frame_control);
 321         mask_fc = hdr->frame_control;
 322         mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
 323                                 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
 324         if (!mgmt)
 325                 mask_fc &= ~cpu_to_le16(0x0070);
 326         mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
 327
 328         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 329         len_a = hdrlen - 2;
 330         a4_included = ieee80211_has_a4(hdr->frame_control);
 331
 332         if (ieee80211_is_data_qos(hdr->frame_control))
 333                 qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
 334         else
 335                 qos_tid = 0;
 336
 337         /* In CCM, the initial vectors (IV) used for CTR mode encryption and CBC
 338          * mode authentication are not allowed to collide, yet both are derived
 339          * from this vector b_0. We only set L := 1 here to indicate that the
 340          * data size can be represented in (L+1) bytes. The CCM layer will take
 341          * care of storing the data length in the top (L+1) bytes and setting
 342          * and clearing the other bits as is required to derive the two IVs.
 343          */
 344         b_0[0] = 0x1;
 345
 346         /* Nonce: Nonce Flags | A2 | PN
 347          * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7)
 348          */
 349         b_0[1] = qos_tid | (mgmt << 4);
 350         memcpy(&b_0[2], hdr->addr2, ETH_ALEN);
 351         memcpy(&b_0[8], pn, IEEE80211_CCMP_PN_LEN);
 352
 353         /* AAD (extra authenticate-only data) / masked 802.11 header
 354          * FC | A1 | A2 | A3 | SC | [A4] | [QC] */
 355         put_unaligned_be16(len_a, &aad[0]);
 356         put_unaligned(mask_fc, (__le16 *)&aad[2]);
 357         memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
 358
 359         /* Mask Seq#, leave Frag# */
 360         aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;
 361         aad[23] = 0;
 362
 363         if (a4_included) {
 364                 memcpy(&aad[24], hdr->addr4, ETH_ALEN);
 365                 aad[30] = qos_tid;
 366                 aad[31] = 0;
 367         } else {
 368                 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
 369                 aad[24] = qos_tid;
 370         }
 371 }
 372
 373
 374 static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)
 375 {
 376         hdr[0] = pn[5];
 377         hdr[1] = pn[4];
 378         hdr[2] = 0;
 379         hdr[3] = 0x20 | (key_id << 6);
 380         hdr[4] = pn[3];
 381         hdr[5] = pn[2];
 382         hdr[6] = pn[1];
 383         hdr[7] = pn[0];
 384 }
 385
 386
 387 static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr)
 388 {
 389         pn[0] = hdr[7];
 390         pn[1] = hdr[6];
 391         pn[2] = hdr[5];
 392         pn[3] = hdr[4];
 393         pn[4] = hdr[1];
 394         pn[5] = hdr[0];
 395 }
 396
 397
 398 static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb,
 399                             unsigned int mic_len)
 400 {
 401         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 402         struct ieee80211_key *key = tx->key;
 403         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 404         int hdrlen, len, tail;
 405         u8 *pos;
 406         u8 pn[6];
 407         u64 pn64;
 408         u8 aad[2 * AES_BLOCK_SIZE];
 409         u8 b_0[AES_BLOCK_SIZE];
 410
 411         if (info->control.hw_key &&
 412             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 413             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 414             !((info->control.hw_key->flags &
 415                IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
 416               ieee80211_is_mgmt(hdr->frame_control))) {
 417                 /*
 418                  * hwaccel has no need for preallocated room for CCMP
 419                  * header or MIC fields
 420                  */
 421                 return 0;
 422         }
 423
 424         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 425         len = skb->len - hdrlen;
 426
 427         if (info->control.hw_key)
 428                 tail = 0;
 429         else
 430                 tail = mic_len;
 431
 432         if (WARN_ON(skb_tailroom(skb) < tail ||
 433                     skb_headroom(skb) < IEEE80211_CCMP_HDR_LEN))
 434                 return -1;
 435
 436         pos = skb_push(skb, IEEE80211_CCMP_HDR_LEN);
 437         memmove(pos, pos + IEEE80211_CCMP_HDR_LEN, hdrlen);
 438
 439         /* the HW only needs room for the IV, but not the actual IV */
 440         if (info->control.hw_key &&
 441             (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 442                 return 0;
 443
 444         hdr = (struct ieee80211_hdr *) pos;
 445         pos += hdrlen;
 446
 447         pn64 = atomic64_inc_return(&key->u.ccmp.tx_pn);
 448
 449         pn[5] = pn64;
 450         pn[4] = pn64 >> 8;
 451         pn[3] = pn64 >> 16;
 452         pn[2] = pn64 >> 24;
 453         pn[1] = pn64 >> 32;
 454         pn[0] = pn64 >> 40;
 455
 456         ccmp_pn2hdr(pos, pn, key->conf.keyidx);
 457
 458         /* hwaccel - with software CCMP header */
 459         if (info->control.hw_key)
 460                 return 0;
 461
 462         pos += IEEE80211_CCMP_HDR_LEN;
 463         ccmp_special_blocks(skb, pn, b_0, aad);
 464         ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, b_0, aad, pos, len,
 465                                   skb_put(skb, mic_len), mic_len);
 466
 467         return 0;
 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         data_len = skb->len - hdrlen - IEEE80211_CCMP_HDR_LEN - mic_len;
 508         if (!rx->sta || data_len < 0)
 509                 return RX_DROP_UNUSABLE;
 510
 511         if (status->flag & RX_FLAG_DECRYPTED) {
 512                 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_CCMP_HDR_LEN))
 513                         return RX_DROP_UNUSABLE;
 514         } else {
 515                 if (skb_linearize(rx->skb))
 516                         return RX_DROP_UNUSABLE;
 517         }
 518
 519         ccmp_hdr2pn(pn, skb->data + hdrlen);
 520
 521         queue = rx->security_idx;
 522
 523         if (memcmp(pn, key->u.ccmp.rx_pn[queue], IEEE80211_CCMP_PN_LEN) <= 0) {
 524                 key->u.ccmp.replays++;
 525                 return RX_DROP_UNUSABLE;
 526         }
 527
 528         if (!(status->flag & RX_FLAG_DECRYPTED)) {
 529                 u8 aad[2 * AES_BLOCK_SIZE];
 530                 u8 b_0[AES_BLOCK_SIZE];
 531                 /* hardware didn't decrypt/verify MIC */
 532                 ccmp_special_blocks(skb, pn, b_0, aad);
 533
 534                 if (ieee80211_aes_ccm_decrypt(
 535                             key->u.ccmp.tfm, b_0, aad,
 536                             skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN,
 537                             data_len,
 538                             skb->data + skb->len - mic_len, mic_len))
 539                         return RX_DROP_UNUSABLE;
 540         }
 541
 542         memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN);
 543
 544         /* Remove CCMP header and MIC */
 545         if (pskb_trim(skb, skb->len - mic_len))
 546                 return RX_DROP_UNUSABLE;
 547         memmove(skb->data + IEEE80211_CCMP_HDR_LEN, skb->data, hdrlen);
 548         skb_pull(skb, IEEE80211_CCMP_HDR_LEN);
 549
 550         return RX_CONTINUE;
 551 }
 552
 553 static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad)
 554 {
 555         __le16 mask_fc;
 556         u8 qos_tid;
 557         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 558
 559         memcpy(j_0, hdr->addr2, ETH_ALEN);
 560         memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN);
 561         j_0[13] = 0;
 562         j_0[14] = 0;
 563         j_0[AES_BLOCK_SIZE - 1] = 0x01;
 564
 565         /* AAD (extra authenticate-only data) / masked 802.11 header
 566          * FC | A1 | A2 | A3 | SC | [A4] | [QC]
 567          */
 568         put_unaligned_be16(ieee80211_hdrlen(hdr->frame_control) - 2, &aad[0]);
 569         /* Mask FC: zero subtype b4 b5 b6 (if not mgmt)
 570          * Retry, PwrMgt, MoreData; set Protected
 571          */
 572         mask_fc = hdr->frame_control;
 573         mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
 574                                 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
 575         if (!ieee80211_is_mgmt(hdr->frame_control))
 576                 mask_fc &= ~cpu_to_le16(0x0070);
 577         mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
 578
 579         put_unaligned(mask_fc, (__le16 *)&aad[2]);
 580         memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
 581
 582         /* Mask Seq#, leave Frag# */
 583         aad[22] = *((u8 *)&hdr->seq_ctrl) & 0x0f;
 584         aad[23] = 0;
 585
 586         if (ieee80211_is_data_qos(hdr->frame_control))
 587                 qos_tid = *ieee80211_get_qos_ctl(hdr) &
 588                         IEEE80211_QOS_CTL_TID_MASK;
 589         else
 590                 qos_tid = 0;
 591
 592         if (ieee80211_has_a4(hdr->frame_control)) {
 593                 memcpy(&aad[24], hdr->addr4, ETH_ALEN);
 594                 aad[30] = qos_tid;
 595                 aad[31] = 0;
 596         } else {
 597                 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
 598                 aad[24] = qos_tid;
 599         }
 600 }
 601
 602 static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id)
 603 {
 604         hdr[0] = pn[5];
 605         hdr[1] = pn[4];
 606         hdr[2] = 0;
 607         hdr[3] = 0x20 | (key_id << 6);
 608         hdr[4] = pn[3];
 609         hdr[5] = pn[2];
 610         hdr[6] = pn[1];
 611         hdr[7] = pn[0];
 612 }
 613
 614 static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr)
 615 {
 616         pn[0] = hdr[7];
 617         pn[1] = hdr[6];
 618         pn[2] = hdr[5];
 619         pn[3] = hdr[4];
 620         pn[4] = hdr[1];
 621         pn[5] = hdr[0];
 622 }
 623
 624 static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
 625 {
 626         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 627         struct ieee80211_key *key = tx->key;
 628         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 629         int hdrlen, len, tail;
 630         u8 *pos;
 631         u8 pn[6];
 632         u64 pn64;
 633         u8 aad[2 * AES_BLOCK_SIZE];
 634         u8 j_0[AES_BLOCK_SIZE];
 635
 636         if (info->control.hw_key &&
 637             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 638             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 639             !((info->control.hw_key->flags &
 640                IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
 641               ieee80211_is_mgmt(hdr->frame_control))) {
 642                 /* hwaccel has no need for preallocated room for GCMP
 643                  * header or MIC fields
 644                  */
 645                 return 0;
 646         }
 647
 648         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 649         len = skb->len - hdrlen;
 650
 651         if (info->control.hw_key)
 652                 tail = 0;
 653         else
 654                 tail = IEEE80211_GCMP_MIC_LEN;
 655
 656         if (WARN_ON(skb_tailroom(skb) < tail ||
 657                     skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN))
 658                 return -1;
 659
 660         pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN);
 661         memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen);
 662         skb_set_network_header(skb, skb_network_offset(skb) +
 663                                     IEEE80211_GCMP_HDR_LEN);
 664
 665         /* the HW only needs room for the IV, but not the actual IV */
 666         if (info->control.hw_key &&
 667             (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 668                 return 0;
 669
 670         hdr = (struct ieee80211_hdr *)pos;
 671         pos += hdrlen;
 672
 673         pn64 = atomic64_inc_return(&key->u.gcmp.tx_pn);
 674
 675         pn[5] = pn64;
 676         pn[4] = pn64 >> 8;
 677         pn[3] = pn64 >> 16;
 678         pn[2] = pn64 >> 24;
 679         pn[1] = pn64 >> 32;
 680         pn[0] = pn64 >> 40;
 681
 682         gcmp_pn2hdr(pos, pn, key->conf.keyidx);
 683
 684         /* hwaccel - with software GCMP header */
 685         if (info->control.hw_key)
 686                 return 0;
 687
 688         pos += IEEE80211_GCMP_HDR_LEN;
 689         gcmp_special_blocks(skb, pn, j_0, aad);
 690         ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len,
 691                                   skb_put(skb, IEEE80211_GCMP_MIC_LEN));
 692
 693         return 0;
 694 }
 695
 696 ieee80211_tx_result
 697 ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx)
 698 {
 699         struct sk_buff *skb;
 700
 701         ieee80211_tx_set_protected(tx);
 702
 703         skb_queue_walk(&tx->skbs, skb) {
 704                 if (gcmp_encrypt_skb(tx, skb) < 0)
 705                         return TX_DROP;
 706         }
 707
 708         return TX_CONTINUE;
 709 }
 710
 711 ieee80211_rx_result
 712 ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
 713 {
 714         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 715         int hdrlen;
 716         struct ieee80211_key *key = rx->key;
 717         struct sk_buff *skb = rx->skb;
 718         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 719         u8 pn[IEEE80211_GCMP_PN_LEN];
 720         int data_len;
 721         int queue;
 722
 723         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 724
 725         if (!ieee80211_is_data(hdr->frame_control) &&
 726             !ieee80211_is_robust_mgmt_frame(skb))
 727                 return RX_CONTINUE;
 728
 729         data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN -
 730                    IEEE80211_GCMP_MIC_LEN;
 731         if (!rx->sta || data_len < 0)
 732                 return RX_DROP_UNUSABLE;
 733
 734         if (status->flag & RX_FLAG_DECRYPTED) {
 735                 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN))
 736                         return RX_DROP_UNUSABLE;
 737         } else {
 738                 if (skb_linearize(rx->skb))
 739                         return RX_DROP_UNUSABLE;
 740         }
 741
 742         gcmp_hdr2pn(pn, skb->data + hdrlen);
 743
 744         queue = rx->security_idx;
 745
 746         if (memcmp(pn, key->u.gcmp.rx_pn[queue], IEEE80211_GCMP_PN_LEN) <= 0) {
 747                 key->u.gcmp.replays++;
 748                 return RX_DROP_UNUSABLE;
 749         }
 750
 751         if (!(status->flag & RX_FLAG_DECRYPTED)) {
 752                 u8 aad[2 * AES_BLOCK_SIZE];
 753                 u8 j_0[AES_BLOCK_SIZE];
 754                 /* hardware didn't decrypt/verify MIC */
 755                 gcmp_special_blocks(skb, pn, j_0, aad);
 756
 757                 if (ieee80211_aes_gcm_decrypt(
 758                             key->u.gcmp.tfm, j_0, aad,
 759                             skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN,
 760                             data_len,
 761                             skb->data + skb->len - IEEE80211_GCMP_MIC_LEN))
 762                         return RX_DROP_UNUSABLE;
 763         }
 764
 765         memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN);
 766
 767         /* Remove GCMP header and MIC */
 768         if (pskb_trim(skb, skb->len - IEEE80211_GCMP_MIC_LEN))
 769                 return RX_DROP_UNUSABLE;
 770         memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen);
 771         skb_pull(skb, IEEE80211_GCMP_HDR_LEN);
 772
 773         return RX_CONTINUE;
 774 }
 775
 776 static ieee80211_tx_result
 777 ieee80211_crypto_cs_encrypt(struct ieee80211_tx_data *tx,
 778                             struct sk_buff *skb)
 779 {
 780         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 781         struct ieee80211_key *key = tx->key;
 782         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 783         int hdrlen;
 784         u8 *pos, iv_len = key->conf.iv_len;
 785
 786         if (info->control.hw_key &&
 787             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
 788                 /* hwaccel has no need for preallocated head room */
 789                 return TX_CONTINUE;
 790         }
 791
 792         if (unlikely(skb_headroom(skb) < iv_len &&
 793                      pskb_expand_head(skb, iv_len, 0, GFP_ATOMIC)))
 794                 return TX_DROP;
 795
 796         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 797
 798         pos = skb_push(skb, iv_len);
 799         memmove(pos, pos + iv_len, hdrlen);
 800
 801         return TX_CONTINUE;
 802 }
 803
 804 static inline int ieee80211_crypto_cs_pn_compare(u8 *pn1, u8 *pn2, int len)
 805 {
 806         int i;
 807
 808         /* pn is little endian */
 809         for (i = len - 1; i >= 0; i--) {
 810                 if (pn1[i] < pn2[i])
 811                         return -1;
 812                 else if (pn1[i] > pn2[i])
 813                         return 1;
 814         }
 815
 816         return 0;
 817 }
 818
 819 static ieee80211_rx_result
 820 ieee80211_crypto_cs_decrypt(struct ieee80211_rx_data *rx)
 821 {
 822         struct ieee80211_key *key = rx->key;
 823         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 824         const struct ieee80211_cipher_scheme *cs = NULL;
 825         int hdrlen = ieee80211_hdrlen(hdr->frame_control);
 826         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 827         int data_len;
 828         u8 *rx_pn;
 829         u8 *skb_pn;
 830         u8 qos_tid;
 831
 832         if (!rx->sta || !rx->sta->cipher_scheme ||
 833             !(status->flag & RX_FLAG_DECRYPTED))
 834                 return RX_DROP_UNUSABLE;
 835
 836         if (!ieee80211_is_data(hdr->frame_control))
 837                 return RX_CONTINUE;
 838
 839         cs = rx->sta->cipher_scheme;
 840
 841         data_len = rx->skb->len - hdrlen - cs->hdr_len;
 842
 843         if (data_len < 0)
 844                 return RX_DROP_UNUSABLE;
 845
 846         if (ieee80211_is_data_qos(hdr->frame_control))
 847                 qos_tid = *ieee80211_get_qos_ctl(hdr) &
 848                                 IEEE80211_QOS_CTL_TID_MASK;
 849         else
 850                 qos_tid = 0;
 851
 852         if (skb_linearize(rx->skb))
 853                 return RX_DROP_UNUSABLE;
 854
 855         hdr = (struct ieee80211_hdr *)rx->skb->data;
 856
 857         rx_pn = key->u.gen.rx_pn[qos_tid];
 858         skb_pn = rx->skb->data + hdrlen + cs->pn_off;
 859
 860         if (ieee80211_crypto_cs_pn_compare(skb_pn, rx_pn, cs->pn_len) <= 0)
 861                 return RX_DROP_UNUSABLE;
 862
 863         memcpy(rx_pn, skb_pn, cs->pn_len);
 864
 865         /* remove security header and MIC */
 866         if (pskb_trim(rx->skb, rx->skb->len - cs->mic_len))
 867                 return RX_DROP_UNUSABLE;
 868
 869         memmove(rx->skb->data + cs->hdr_len, rx->skb->data, hdrlen);
 870         skb_pull(rx->skb, cs->hdr_len);
 871
 872         return RX_CONTINUE;
 873 }
 874
 875 static void bip_aad(struct sk_buff *skb, u8 *aad)
 876 {
 877         __le16 mask_fc;
 878         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 879
 880         /* BIP AAD: FC(masked) || A1 || A2 || A3 */
 881
 882         /* FC type/subtype */
 883         /* Mask FC Retry, PwrMgt, MoreData flags to zero */
 884         mask_fc = hdr->frame_control;
 885         mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM |
 886                                 IEEE80211_FCTL_MOREDATA);
 887         put_unaligned(mask_fc, (__le16 *) &aad[0]);
 888         /* A1 || A2 || A3 */
 889         memcpy(aad + 2, &hdr->addr1, 3 * ETH_ALEN);
 890 }
 891
 892
 893 static inline void bip_ipn_set64(u8 *d, u64 pn)
 894 {
 895         *d++ = pn;
 896         *d++ = pn >> 8;
 897         *d++ = pn >> 16;
 898         *d++ = pn >> 24;
 899         *d++ = pn >> 32;
 900         *d = pn >> 40;
 901 }
 902
 903 static inline void bip_ipn_swap(u8 *d, const u8 *s)
 904 {
 905         *d++ = s[5];
 906         *d++ = s[4];
 907         *d++ = s[3];
 908         *d++ = s[2];
 909         *d++ = s[1];
 910         *d = s[0];
 911 }
 912
 913
 914 ieee80211_tx_result
 915 ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
 916 {
 917         struct sk_buff *skb;
 918         struct ieee80211_tx_info *info;
 919         struct ieee80211_key *key = tx->key;
 920         struct ieee80211_mmie *mmie;
 921         u8 aad[20];
 922         u64 pn64;
 923
 924         if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
 925                 return TX_DROP;
 926
 927         skb = skb_peek(&tx->skbs);
 928
 929         info = IEEE80211_SKB_CB(skb);
 930
 931         if (info->control.hw_key)
 932                 return TX_CONTINUE;
 933
 934         if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
 935                 return TX_DROP;
 936
 937         mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie));
 938         mmie->element_id = WLAN_EID_MMIE;
 939         mmie->length = sizeof(*mmie) - 2;
 940         mmie->key_id = cpu_to_le16(key->conf.keyidx);
 941
 942         /* PN = PN + 1 */
 943         pn64 = atomic64_inc_return(&key->u.aes_cmac.tx_pn);
 944
 945         bip_ipn_set64(mmie->sequence_number, pn64);
 946
 947         bip_aad(skb, aad);
 948
 949         /*
 950          * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
 951          */
 952         ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
 953                            skb->data + 24, skb->len - 24, mmie->mic);
 954
 955         return TX_CONTINUE;
 956 }
 957
 958 ieee80211_tx_result
 959 ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx)
 960 {
 961         struct sk_buff *skb;
 962         struct ieee80211_tx_info *info;
 963         struct ieee80211_key *key = tx->key;
 964         struct ieee80211_mmie_16 *mmie;
 965         u8 aad[20];
 966         u64 pn64;
 967
 968         if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
 969                 return TX_DROP;
 970
 971         skb = skb_peek(&tx->skbs);
 972
 973         info = IEEE80211_SKB_CB(skb);
 974
 975         if (info->control.hw_key)
 976                 return TX_CONTINUE;
 977
 978         if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
 979                 return TX_DROP;
 980
 981         mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie));
 982         mmie->element_id = WLAN_EID_MMIE;
 983         mmie->length = sizeof(*mmie) - 2;
 984         mmie->key_id = cpu_to_le16(key->conf.keyidx);
 985
 986         /* PN = PN + 1 */
 987         pn64 = atomic64_inc_return(&key->u.aes_cmac.tx_pn);
 988
 989         bip_ipn_set64(mmie->sequence_number, pn64);
 990
 991         bip_aad(skb, aad);
 992
 993         /* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128)
 994          */
 995         ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
 996                                skb->data + 24, skb->len - 24, mmie->mic);
 997
 998         return TX_CONTINUE;
 999 }
1000
1001 ieee80211_rx_result
1002 ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
1003 {
1004         struct sk_buff *skb = rx->skb;
1005         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1006         struct ieee80211_key *key = rx->key;
1007         struct ieee80211_mmie *mmie;
1008         u8 aad[20], mic[8], ipn[6];
1009         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1010
1011         if (!ieee80211_is_mgmt(hdr->frame_control))
1012                 return RX_CONTINUE;
1013
1014         /* management frames are already linear */
1015
1016         if (skb->len < 24 + sizeof(*mmie))
1017                 return RX_DROP_UNUSABLE;
1018
1019         mmie = (struct ieee80211_mmie *)
1020                 (skb->data + skb->len - sizeof(*mmie));
1021         if (mmie->element_id != WLAN_EID_MMIE ||
1022             mmie->length != sizeof(*mmie) - 2)
1023                 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1024
1025         bip_ipn_swap(ipn, mmie->sequence_number);
1026
1027         if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1028                 key->u.aes_cmac.replays++;
1029                 return RX_DROP_UNUSABLE;
1030         }
1031
1032         if (!(status->flag & RX_FLAG_DECRYPTED)) {
1033                 /* hardware didn't decrypt/verify MIC */
1034                 bip_aad(skb, aad);
1035                 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
1036                                    skb->data + 24, skb->len - 24, mic);
1037                 if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1038                         key->u.aes_cmac.icverrors++;
1039                         return RX_DROP_UNUSABLE;
1040                 }
1041         }
1042
1043         memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1044
1045         /* Remove MMIE */
1046         skb_trim(skb, skb->len - sizeof(*mmie));
1047
1048         return RX_CONTINUE;
1049 }
1050
1051 ieee80211_rx_result
1052 ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx)
1053 {
1054         struct sk_buff *skb = rx->skb;
1055         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1056         struct ieee80211_key *key = rx->key;
1057         struct ieee80211_mmie_16 *mmie;
1058         u8 aad[20], mic[16], ipn[6];
1059         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1060
1061         if (!ieee80211_is_mgmt(hdr->frame_control))
1062                 return RX_CONTINUE;
1063
1064         /* management frames are already linear */
1065
1066         if (skb->len < 24 + sizeof(*mmie))
1067                 return RX_DROP_UNUSABLE;
1068
1069         mmie = (struct ieee80211_mmie_16 *)
1070                 (skb->data + skb->len - sizeof(*mmie));
1071         if (mmie->element_id != WLAN_EID_MMIE ||
1072             mmie->length != sizeof(*mmie) - 2)
1073                 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1074
1075         bip_ipn_swap(ipn, mmie->sequence_number);
1076
1077         if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1078                 key->u.aes_cmac.replays++;
1079                 return RX_DROP_UNUSABLE;
1080         }
1081
1082         if (!(status->flag & RX_FLAG_DECRYPTED)) {
1083                 /* hardware didn't decrypt/verify MIC */
1084                 bip_aad(skb, aad);
1085                 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1086                                        skb->data + 24, skb->len - 24, mic);
1087                 if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1088                         key->u.aes_cmac.icverrors++;
1089                         return RX_DROP_UNUSABLE;
1090                 }
1091         }
1092
1093         memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1094
1095         /* Remove MMIE */
1096         skb_trim(skb, skb->len - sizeof(*mmie));
1097
1098         return RX_CONTINUE;
1099 }
1100
1101 ieee80211_tx_result
1102 ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx)
1103 {
1104         struct sk_buff *skb;
1105         struct ieee80211_tx_info *info;
1106         struct ieee80211_key *key = tx->key;
1107         struct ieee80211_mmie_16 *mmie;
1108         struct ieee80211_hdr *hdr;
1109         u8 aad[20];
1110         u64 pn64;
1111         u8 nonce[12];
1112
1113         if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
1114                 return TX_DROP;
1115
1116         skb = skb_peek(&tx->skbs);
1117
1118         info = IEEE80211_SKB_CB(skb);
1119
1120         if (info->control.hw_key)
1121                 return TX_CONTINUE;
1122
1123         if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
1124                 return TX_DROP;
1125
1126         mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie));
1127         mmie->element_id = WLAN_EID_MMIE;
1128         mmie->length = sizeof(*mmie) - 2;
1129         mmie->key_id = cpu_to_le16(key->conf.keyidx);
1130
1131         /* PN = PN + 1 */
1132         pn64 = atomic64_inc_return(&key->u.aes_gmac.tx_pn);
1133
1134         bip_ipn_set64(mmie->sequence_number, pn64);
1135
1136         bip_aad(skb, aad);
1137
1138         hdr = (struct ieee80211_hdr *)skb->data;
1139         memcpy(nonce, hdr->addr2, ETH_ALEN);
1140         bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number);
1141
1142         /* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */
1143         if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1144                                skb->data + 24, skb->len - 24, mmie->mic) < 0)
1145                 return TX_DROP;
1146
1147         return TX_CONTINUE;
1148 }
1149
1150 ieee80211_rx_result
1151 ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx)
1152 {
1153         struct sk_buff *skb = rx->skb;
1154         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1155         struct ieee80211_key *key = rx->key;
1156         struct ieee80211_mmie_16 *mmie;
1157         u8 aad[20], mic[16], ipn[6], nonce[12];
1158         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1159
1160         if (!ieee80211_is_mgmt(hdr->frame_control))
1161                 return RX_CONTINUE;
1162
1163         /* management frames are already linear */
1164
1165         if (skb->len < 24 + sizeof(*mmie))
1166                 return RX_DROP_UNUSABLE;
1167
1168         mmie = (struct ieee80211_mmie_16 *)
1169                 (skb->data + skb->len - sizeof(*mmie));
1170         if (mmie->element_id != WLAN_EID_MMIE ||
1171             mmie->length != sizeof(*mmie) - 2)
1172                 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1173
1174         bip_ipn_swap(ipn, mmie->sequence_number);
1175
1176         if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) {
1177                 key->u.aes_gmac.replays++;
1178                 return RX_DROP_UNUSABLE;
1179         }
1180
1181         if (!(status->flag & RX_FLAG_DECRYPTED)) {
1182                 /* hardware didn't decrypt/verify MIC */
1183                 bip_aad(skb, aad);
1184
1185                 memcpy(nonce, hdr->addr2, ETH_ALEN);
1186                 memcpy(nonce + ETH_ALEN, ipn, 6);
1187
1188                 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1189                                        skb->data + 24, skb->len - 24,
1190                                        mic) < 0 ||
1191                     memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1192                         key->u.aes_gmac.icverrors++;
1193                         return RX_DROP_UNUSABLE;
1194                 }
1195         }
1196
1197         memcpy(key->u.aes_gmac.rx_pn, ipn, 6);
1198
1199         /* Remove MMIE */
1200         skb_trim(skb, skb->len - sizeof(*mmie));
1201
1202         return RX_CONTINUE;
1203 }
1204
1205 ieee80211_tx_result
1206 ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx)
1207 {
1208         struct sk_buff *skb;
1209         struct ieee80211_tx_info *info = NULL;
1210         ieee80211_tx_result res;
1211
1212         skb_queue_walk(&tx->skbs, skb) {
1213                 info  = IEEE80211_SKB_CB(skb);
1214
1215                 /* handle hw-only algorithm */
1216                 if (!info->control.hw_key)
1217                         return TX_DROP;
1218
1219                 if (tx->key->flags & KEY_FLAG_CIPHER_SCHEME) {
1220                         res = ieee80211_crypto_cs_encrypt(tx, skb);
1221                         if (res != TX_CONTINUE)
1222                                 return res;
1223                 }
1224         }
1225
1226         ieee80211_tx_set_protected(tx);
1227
1228         return TX_CONTINUE;
1229 }
1230
1231 ieee80211_rx_result
1232 ieee80211_crypto_hw_decrypt(struct ieee80211_rx_data *rx)
1233 {
1234         if (rx->sta && rx->sta->cipher_scheme)
1235                 return ieee80211_crypto_cs_decrypt(rx);
1236
1237         return RX_DROP_UNUSABLE;
1238 }