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
  21 #include "ieee80211_i.h"
  22 #include "michael.h"
  23 #include "tkip.h"
  24 #include "aes_ccm.h"
  25 #include "aes_cmac.h"
  26 #include "aes_gmac.h"
  27 #include "aes_gcm.h"
  28 #include "wpa.h"
  29
  30 ieee80211_tx_result
  31 ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
  32 {
  33         u8 *data, *key, *mic;
  34         size_t data_len;
  35         unsigned int hdrlen;
  36         struct ieee80211_hdr *hdr;
  37         struct sk_buff *skb = tx->skb;
  38         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  39         int tail;
  40
  41         hdr = (struct ieee80211_hdr *)skb->data;
  42         if (!tx->key || tx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
  43             skb->len < 24 || !ieee80211_is_data_present(hdr->frame_control))
  44                 return TX_CONTINUE;
  45
  46         hdrlen = ieee80211_hdrlen(hdr->frame_control);
  47         if (skb->len < hdrlen)
  48                 return TX_DROP;
  49
  50         data = skb->data + hdrlen;
  51         data_len = skb->len - hdrlen;
  52
  53         if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) {
  54                 /* Need to use software crypto for the test */
  55                 info->control.hw_key = NULL;
  56         }
  57
  58         if (info->control.hw_key &&
  59             (info->flags & IEEE80211_TX_CTL_DONTFRAG ||
  60              tx->local->ops->set_frag_threshold) &&
  61             !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) {
  62                 /* hwaccel - with no need for SW-generated MMIC */
  63                 return TX_CONTINUE;
  64         }
  65
  66         tail = MICHAEL_MIC_LEN;
  67         if (!info->control.hw_key)
  68                 tail += IEEE80211_TKIP_ICV_LEN;
  69
  70         if (WARN(skb_tailroom(skb) < tail ||
  71                  skb_headroom(skb) < IEEE80211_TKIP_IV_LEN,
  72                  "mmic: not enough head/tail (%d/%d,%d/%d)\n",
  73                  skb_headroom(skb), IEEE80211_TKIP_IV_LEN,
  74                  skb_tailroom(skb), tail))
  75                 return TX_DROP;
  76
  77         key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY];
  78         mic = skb_put(skb, MICHAEL_MIC_LEN);
  79         michael_mic(key, hdr, data, data_len, mic);
  80         if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE))
  81                 mic[0]++;
  82
  83         return TX_CONTINUE;
  84 }
  85
  86
  87 ieee80211_rx_result
  88 ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
  89 {
  90         u8 *data, *key = NULL;
  91         size_t data_len;
  92         unsigned int hdrlen;
  93         u8 mic[MICHAEL_MIC_LEN];
  94         struct sk_buff *skb = rx->skb;
  95         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  96         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  97
  98         /*
  99          * it makes no sense to check for MIC errors on anything other
 100          * than data frames.
 101          */
 102         if (!ieee80211_is_data_present(hdr->frame_control))
 103                 return RX_CONTINUE;
 104
 105         /*
 106          * No way to verify the MIC if the hardware stripped it or
 107          * the IV with the key index. In this case we have solely rely
 108          * on the driver to set RX_FLAG_MMIC_ERROR in the event of a
 109          * MIC failure report.
 110          */
 111         if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) {
 112                 if (status->flag & RX_FLAG_MMIC_ERROR)
 113                         goto mic_fail_no_key;
 114
 115                 if (!(status->flag & RX_FLAG_IV_STRIPPED) && rx->key &&
 116                     rx->key->conf.cipher == WLAN_CIPHER_SUITE_TKIP)
 117                         goto update_iv;
 118
 119                 return RX_CONTINUE;
 120         }
 121
 122         /*
 123          * Some hardware seems to generate Michael MIC failure reports; even
 124          * though, the frame was not encrypted with TKIP and therefore has no
 125          * MIC. Ignore the flag them to avoid triggering countermeasures.
 126          */
 127         if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
 128             !(status->flag & RX_FLAG_DECRYPTED))
 129                 return RX_CONTINUE;
 130
 131         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) {
 132                 /*
 133                  * APs with pairwise keys should never receive Michael MIC
 134                  * errors for non-zero keyidx because these are reserved for
 135                  * group keys and only the AP is sending real multicast
 136                  * frames in the BSS.
 137                  */
 138                 return RX_DROP_UNUSABLE;
 139         }
 140
 141         if (status->flag & RX_FLAG_MMIC_ERROR)
 142                 goto mic_fail;
 143
 144         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 145         if (skb->len < hdrlen + MICHAEL_MIC_LEN)
 146                 return RX_DROP_UNUSABLE;
 147
 148         if (skb_linearize(rx->skb))
 149                 return RX_DROP_UNUSABLE;
 150         hdr = (void *)skb->data;
 151
 152         data = skb->data + hdrlen;
 153         data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;
 154         key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY];
 155         michael_mic(key, hdr, data, data_len, mic);
 156         if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0)
 157                 goto mic_fail;
 158
 159         /* remove Michael MIC from payload */
 160         skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
 161
 162 update_iv:
 163         /* update IV in key information to be able to detect replays */
 164         rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip_iv32;
 165         rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip_iv16;
 166
 167         return RX_CONTINUE;
 168
 169 mic_fail:
 170         rx->key->u.tkip.mic_failures++;
 171
 172 mic_fail_no_key:
 173         /*
 174          * In some cases the key can be unset - e.g. a multicast packet, in
 175          * a driver that supports HW encryption. Send up the key idx only if
 176          * the key is set.
 177          */
 178         cfg80211_michael_mic_failure(rx->sdata->dev, hdr->addr2,
 179                                      is_multicast_ether_addr(hdr->addr1) ?
 180                                      NL80211_KEYTYPE_GROUP :
 181                                      NL80211_KEYTYPE_PAIRWISE,
 182                                      rx->key ? rx->key->conf.keyidx : -1,
 183                                      NULL, GFP_ATOMIC);
 184         return RX_DROP_UNUSABLE;
 185 }
 186
 187 static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
 188 {
 189         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 190         struct ieee80211_key *key = tx->key;
 191         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 192         unsigned int hdrlen;
 193         int len, tail;
 194         u64 pn;
 195         u8 *pos;
 196
 197         if (info->control.hw_key &&
 198             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 199             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
 200                 /* hwaccel - with no need for software-generated IV */
 201                 return 0;
 202         }
 203
 204         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 205         len = skb->len - hdrlen;
 206
 207         if (info->control.hw_key)
 208                 tail = 0;
 209         else
 210                 tail = IEEE80211_TKIP_ICV_LEN;
 211
 212         if (WARN_ON(skb_tailroom(skb) < tail ||
 213                     skb_headroom(skb) < IEEE80211_TKIP_IV_LEN))
 214                 return -1;
 215
 216         pos = skb_push(skb, IEEE80211_TKIP_IV_LEN);
 217         memmove(pos, pos + IEEE80211_TKIP_IV_LEN, hdrlen);
 218         pos += hdrlen;
 219
 220         /* the HW only needs room for the IV, but not the actual IV */
 221         if (info->control.hw_key &&
 222             (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 223                 return 0;
 224
 225         /* Increase IV for the frame */
 226         pn = atomic64_inc_return(&key->conf.tx_pn);
 227         pos = ieee80211_tkip_add_iv(pos, &key->conf, pn);
 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->conf.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         if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
 520                 ccmp_hdr2pn(pn, skb->data + hdrlen);
 521
 522                 queue = rx->security_idx;
 523
 524                 if (memcmp(pn, key->u.ccmp.rx_pn[queue],
 525                            IEEE80211_CCMP_PN_LEN) <= 0) {
 526                         key->u.ccmp.replays++;
 527                         return RX_DROP_UNUSABLE;
 528                 }
 529
 530                 if (!(status->flag & RX_FLAG_DECRYPTED)) {
 531                         u8 aad[2 * AES_BLOCK_SIZE];
 532                         u8 b_0[AES_BLOCK_SIZE];
 533                         /* hardware didn't decrypt/verify MIC */
 534                         ccmp_special_blocks(skb, pn, b_0, aad);
 535
 536                         if (ieee80211_aes_ccm_decrypt(
 537                                     key->u.ccmp.tfm, b_0, aad,
 538                                     skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN,
 539                                     data_len,
 540                                     skb->data + skb->len - mic_len, mic_len))
 541                                 return RX_DROP_UNUSABLE;
 542                 }
 543
 544                 memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN);
 545         }
 546
 547         /* Remove CCMP header and MIC */
 548         if (pskb_trim(skb, skb->len - mic_len))
 549                 return RX_DROP_UNUSABLE;
 550         memmove(skb->data + IEEE80211_CCMP_HDR_LEN, skb->data, hdrlen);
 551         skb_pull(skb, IEEE80211_CCMP_HDR_LEN);
 552
 553         return RX_CONTINUE;
 554 }
 555
 556 static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad)
 557 {
 558         __le16 mask_fc;
 559         u8 qos_tid;
 560         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 561
 562         memcpy(j_0, hdr->addr2, ETH_ALEN);
 563         memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN);
 564         j_0[13] = 0;
 565         j_0[14] = 0;
 566         j_0[AES_BLOCK_SIZE - 1] = 0x01;
 567
 568         /* AAD (extra authenticate-only data) / masked 802.11 header
 569          * FC | A1 | A2 | A3 | SC | [A4] | [QC]
 570          */
 571         put_unaligned_be16(ieee80211_hdrlen(hdr->frame_control) - 2, &aad[0]);
 572         /* Mask FC: zero subtype b4 b5 b6 (if not mgmt)
 573          * Retry, PwrMgt, MoreData; set Protected
 574          */
 575         mask_fc = hdr->frame_control;
 576         mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
 577                                 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
 578         if (!ieee80211_is_mgmt(hdr->frame_control))
 579                 mask_fc &= ~cpu_to_le16(0x0070);
 580         mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
 581
 582         put_unaligned(mask_fc, (__le16 *)&aad[2]);
 583         memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
 584
 585         /* Mask Seq#, leave Frag# */
 586         aad[22] = *((u8 *)&hdr->seq_ctrl) & 0x0f;
 587         aad[23] = 0;
 588
 589         if (ieee80211_is_data_qos(hdr->frame_control))
 590                 qos_tid = *ieee80211_get_qos_ctl(hdr) &
 591                         IEEE80211_QOS_CTL_TID_MASK;
 592         else
 593                 qos_tid = 0;
 594
 595         if (ieee80211_has_a4(hdr->frame_control)) {
 596                 memcpy(&aad[24], hdr->addr4, ETH_ALEN);
 597                 aad[30] = qos_tid;
 598                 aad[31] = 0;
 599         } else {
 600                 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
 601                 aad[24] = qos_tid;
 602         }
 603 }
 604
 605 static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id)
 606 {
 607         hdr[0] = pn[5];
 608         hdr[1] = pn[4];
 609         hdr[2] = 0;
 610         hdr[3] = 0x20 | (key_id << 6);
 611         hdr[4] = pn[3];
 612         hdr[5] = pn[2];
 613         hdr[6] = pn[1];
 614         hdr[7] = pn[0];
 615 }
 616
 617 static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr)
 618 {
 619         pn[0] = hdr[7];
 620         pn[1] = hdr[6];
 621         pn[2] = hdr[5];
 622         pn[3] = hdr[4];
 623         pn[4] = hdr[1];
 624         pn[5] = hdr[0];
 625 }
 626
 627 static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
 628 {
 629         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 630         struct ieee80211_key *key = tx->key;
 631         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 632         int hdrlen, len, tail;
 633         u8 *pos;
 634         u8 pn[6];
 635         u64 pn64;
 636         u8 aad[2 * AES_BLOCK_SIZE];
 637         u8 j_0[AES_BLOCK_SIZE];
 638
 639         if (info->control.hw_key &&
 640             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 641             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 642             !((info->control.hw_key->flags &
 643                IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
 644               ieee80211_is_mgmt(hdr->frame_control))) {
 645                 /* hwaccel has no need for preallocated room for GCMP
 646                  * header or MIC fields
 647                  */
 648                 return 0;
 649         }
 650
 651         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 652         len = skb->len - hdrlen;
 653
 654         if (info->control.hw_key)
 655                 tail = 0;
 656         else
 657                 tail = IEEE80211_GCMP_MIC_LEN;
 658
 659         if (WARN_ON(skb_tailroom(skb) < tail ||
 660                     skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN))
 661                 return -1;
 662
 663         pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN);
 664         memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen);
 665         skb_set_network_header(skb, skb_network_offset(skb) +
 666                                     IEEE80211_GCMP_HDR_LEN);
 667
 668         /* the HW only needs room for the IV, but not the actual IV */
 669         if (info->control.hw_key &&
 670             (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 671                 return 0;
 672
 673         hdr = (struct ieee80211_hdr *)pos;
 674         pos += hdrlen;
 675
 676         pn64 = atomic64_inc_return(&key->conf.tx_pn);
 677
 678         pn[5] = pn64;
 679         pn[4] = pn64 >> 8;
 680         pn[3] = pn64 >> 16;
 681         pn[2] = pn64 >> 24;
 682         pn[1] = pn64 >> 32;
 683         pn[0] = pn64 >> 40;
 684
 685         gcmp_pn2hdr(pos, pn, key->conf.keyidx);
 686
 687         /* hwaccel - with software GCMP header */
 688         if (info->control.hw_key)
 689                 return 0;
 690
 691         pos += IEEE80211_GCMP_HDR_LEN;
 692         gcmp_special_blocks(skb, pn, j_0, aad);
 693         ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len,
 694                                   skb_put(skb, IEEE80211_GCMP_MIC_LEN));
 695
 696         return 0;
 697 }
 698
 699 ieee80211_tx_result
 700 ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx)
 701 {
 702         struct sk_buff *skb;
 703
 704         ieee80211_tx_set_protected(tx);
 705
 706         skb_queue_walk(&tx->skbs, skb) {
 707                 if (gcmp_encrypt_skb(tx, skb) < 0)
 708                         return TX_DROP;
 709         }
 710
 711         return TX_CONTINUE;
 712 }
 713
 714 ieee80211_rx_result
 715 ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
 716 {
 717         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 718         int hdrlen;
 719         struct ieee80211_key *key = rx->key;
 720         struct sk_buff *skb = rx->skb;
 721         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 722         u8 pn[IEEE80211_GCMP_PN_LEN];
 723         int data_len;
 724         int queue;
 725
 726         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 727
 728         if (!ieee80211_is_data(hdr->frame_control) &&
 729             !ieee80211_is_robust_mgmt_frame(skb))
 730                 return RX_CONTINUE;
 731
 732         data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN -
 733                    IEEE80211_GCMP_MIC_LEN;
 734         if (!rx->sta || data_len < 0)
 735                 return RX_DROP_UNUSABLE;
 736
 737         if (status->flag & RX_FLAG_DECRYPTED) {
 738                 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN))
 739                         return RX_DROP_UNUSABLE;
 740         } else {
 741                 if (skb_linearize(rx->skb))
 742                         return RX_DROP_UNUSABLE;
 743         }
 744
 745         if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
 746                 gcmp_hdr2pn(pn, skb->data + hdrlen);
 747
 748                 queue = rx->security_idx;
 749
 750                 if (memcmp(pn, key->u.gcmp.rx_pn[queue],
 751                            IEEE80211_GCMP_PN_LEN) <= 0) {
 752                         key->u.gcmp.replays++;
 753                         return RX_DROP_UNUSABLE;
 754                 }
 755
 756                 if (!(status->flag & RX_FLAG_DECRYPTED)) {
 757                         u8 aad[2 * AES_BLOCK_SIZE];
 758                         u8 j_0[AES_BLOCK_SIZE];
 759                         /* hardware didn't decrypt/verify MIC */
 760                         gcmp_special_blocks(skb, pn, j_0, aad);
 761
 762                         if (ieee80211_aes_gcm_decrypt(
 763                                     key->u.gcmp.tfm, j_0, aad,
 764                                     skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN,
 765                                     data_len,
 766                                     skb->data + skb->len -
 767                                     IEEE80211_GCMP_MIC_LEN))
 768                                 return RX_DROP_UNUSABLE;
 769                 }
 770
 771                 memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN);
 772         }
 773
 774         /* Remove GCMP header and MIC */
 775         if (pskb_trim(skb, skb->len - IEEE80211_GCMP_MIC_LEN))
 776                 return RX_DROP_UNUSABLE;
 777         memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen);
 778         skb_pull(skb, IEEE80211_GCMP_HDR_LEN);
 779
 780         return RX_CONTINUE;
 781 }
 782
 783 static ieee80211_tx_result
 784 ieee80211_crypto_cs_encrypt(struct ieee80211_tx_data *tx,
 785                             struct sk_buff *skb)
 786 {
 787         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 788         struct ieee80211_key *key = tx->key;
 789         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 790         int hdrlen;
 791         u8 *pos, iv_len = key->conf.iv_len;
 792
 793         if (info->control.hw_key &&
 794             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
 795                 /* hwaccel has no need for preallocated head room */
 796                 return TX_CONTINUE;
 797         }
 798
 799         if (unlikely(skb_headroom(skb) < iv_len &&
 800                      pskb_expand_head(skb, iv_len, 0, GFP_ATOMIC)))
 801                 return TX_DROP;
 802
 803         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 804
 805         pos = skb_push(skb, iv_len);
 806         memmove(pos, pos + iv_len, hdrlen);
 807
 808         return TX_CONTINUE;
 809 }
 810
 811 static inline int ieee80211_crypto_cs_pn_compare(u8 *pn1, u8 *pn2, int len)
 812 {
 813         int i;
 814
 815         /* pn is little endian */
 816         for (i = len - 1; i >= 0; i--) {
 817                 if (pn1[i] < pn2[i])
 818                         return -1;
 819                 else if (pn1[i] > pn2[i])
 820                         return 1;
 821         }
 822
 823         return 0;
 824 }
 825
 826 static ieee80211_rx_result
 827 ieee80211_crypto_cs_decrypt(struct ieee80211_rx_data *rx)
 828 {
 829         struct ieee80211_key *key = rx->key;
 830         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 831         const struct ieee80211_cipher_scheme *cs = NULL;
 832         int hdrlen = ieee80211_hdrlen(hdr->frame_control);
 833         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 834         int data_len;
 835         u8 *rx_pn;
 836         u8 *skb_pn;
 837         u8 qos_tid;
 838
 839         if (!rx->sta || !rx->sta->cipher_scheme ||
 840             !(status->flag & RX_FLAG_DECRYPTED))
 841                 return RX_DROP_UNUSABLE;
 842
 843         if (!ieee80211_is_data(hdr->frame_control))
 844                 return RX_CONTINUE;
 845
 846         cs = rx->sta->cipher_scheme;
 847
 848         data_len = rx->skb->len - hdrlen - cs->hdr_len;
 849
 850         if (data_len < 0)
 851                 return RX_DROP_UNUSABLE;
 852
 853         if (ieee80211_is_data_qos(hdr->frame_control))
 854                 qos_tid = *ieee80211_get_qos_ctl(hdr) &
 855                                 IEEE80211_QOS_CTL_TID_MASK;
 856         else
 857                 qos_tid = 0;
 858
 859         if (skb_linearize(rx->skb))
 860                 return RX_DROP_UNUSABLE;
 861
 862         hdr = (struct ieee80211_hdr *)rx->skb->data;
 863
 864         rx_pn = key->u.gen.rx_pn[qos_tid];
 865         skb_pn = rx->skb->data + hdrlen + cs->pn_off;
 866
 867         if (ieee80211_crypto_cs_pn_compare(skb_pn, rx_pn, cs->pn_len) <= 0)
 868                 return RX_DROP_UNUSABLE;
 869
 870         memcpy(rx_pn, skb_pn, cs->pn_len);
 871
 872         /* remove security header and MIC */
 873         if (pskb_trim(rx->skb, rx->skb->len - cs->mic_len))
 874                 return RX_DROP_UNUSABLE;
 875
 876         memmove(rx->skb->data + cs->hdr_len, rx->skb->data, hdrlen);
 877         skb_pull(rx->skb, cs->hdr_len);
 878
 879         return RX_CONTINUE;
 880 }
 881
 882 static void bip_aad(struct sk_buff *skb, u8 *aad)
 883 {
 884         __le16 mask_fc;
 885         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 886
 887         /* BIP AAD: FC(masked) || A1 || A2 || A3 */
 888
 889         /* FC type/subtype */
 890         /* Mask FC Retry, PwrMgt, MoreData flags to zero */
 891         mask_fc = hdr->frame_control;
 892         mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM |
 893                                 IEEE80211_FCTL_MOREDATA);
 894         put_unaligned(mask_fc, (__le16 *) &aad[0]);
 895         /* A1 || A2 || A3 */
 896         memcpy(aad + 2, &hdr->addr1, 3 * ETH_ALEN);
 897 }
 898
 899
 900 static inline void bip_ipn_set64(u8 *d, u64 pn)
 901 {
 902         *d++ = pn;
 903         *d++ = pn >> 8;
 904         *d++ = pn >> 16;
 905         *d++ = pn >> 24;
 906         *d++ = pn >> 32;
 907         *d = pn >> 40;
 908 }
 909
 910 static inline void bip_ipn_swap(u8 *d, const u8 *s)
 911 {
 912         *d++ = s[5];
 913         *d++ = s[4];
 914         *d++ = s[3];
 915         *d++ = s[2];
 916         *d++ = s[1];
 917         *d = s[0];
 918 }
 919
 920
 921 ieee80211_tx_result
 922 ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
 923 {
 924         struct sk_buff *skb;
 925         struct ieee80211_tx_info *info;
 926         struct ieee80211_key *key = tx->key;
 927         struct ieee80211_mmie *mmie;
 928         u8 aad[20];
 929         u64 pn64;
 930
 931         if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
 932                 return TX_DROP;
 933
 934         skb = skb_peek(&tx->skbs);
 935
 936         info = IEEE80211_SKB_CB(skb);
 937
 938         if (info->control.hw_key)
 939                 return TX_CONTINUE;
 940
 941         if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
 942                 return TX_DROP;
 943
 944         mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie));
 945         mmie->element_id = WLAN_EID_MMIE;
 946         mmie->length = sizeof(*mmie) - 2;
 947         mmie->key_id = cpu_to_le16(key->conf.keyidx);
 948
 949         /* PN = PN + 1 */
 950         pn64 = atomic64_inc_return(&key->conf.tx_pn);
 951
 952         bip_ipn_set64(mmie->sequence_number, pn64);
 953
 954         bip_aad(skb, aad);
 955
 956         /*
 957          * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
 958          */
 959         ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
 960                            skb->data + 24, skb->len - 24, mmie->mic);
 961
 962         return TX_CONTINUE;
 963 }
 964
 965 ieee80211_tx_result
 966 ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx)
 967 {
 968         struct sk_buff *skb;
 969         struct ieee80211_tx_info *info;
 970         struct ieee80211_key *key = tx->key;
 971         struct ieee80211_mmie_16 *mmie;
 972         u8 aad[20];
 973         u64 pn64;
 974
 975         if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
 976                 return TX_DROP;
 977
 978         skb = skb_peek(&tx->skbs);
 979
 980         info = IEEE80211_SKB_CB(skb);
 981
 982         if (info->control.hw_key)
 983                 return TX_CONTINUE;
 984
 985         if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
 986                 return TX_DROP;
 987
 988         mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie));
 989         mmie->element_id = WLAN_EID_MMIE;
 990         mmie->length = sizeof(*mmie) - 2;
 991         mmie->key_id = cpu_to_le16(key->conf.keyidx);
 992
 993         /* PN = PN + 1 */
 994         pn64 = atomic64_inc_return(&key->conf.tx_pn);
 995
 996         bip_ipn_set64(mmie->sequence_number, pn64);
 997
 998         bip_aad(skb, aad);
 999
1000         /* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128)
1001          */
1002         ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1003                                skb->data + 24, skb->len - 24, mmie->mic);
1004
1005         return TX_CONTINUE;
1006 }
1007
1008 ieee80211_rx_result
1009 ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
1010 {
1011         struct sk_buff *skb = rx->skb;
1012         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1013         struct ieee80211_key *key = rx->key;
1014         struct ieee80211_mmie *mmie;
1015         u8 aad[20], mic[8], ipn[6];
1016         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1017
1018         if (!ieee80211_is_mgmt(hdr->frame_control))
1019                 return RX_CONTINUE;
1020
1021         /* management frames are already linear */
1022
1023         if (skb->len < 24 + sizeof(*mmie))
1024                 return RX_DROP_UNUSABLE;
1025
1026         mmie = (struct ieee80211_mmie *)
1027                 (skb->data + skb->len - sizeof(*mmie));
1028         if (mmie->element_id != WLAN_EID_MMIE ||
1029             mmie->length != sizeof(*mmie) - 2)
1030                 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1031
1032         bip_ipn_swap(ipn, mmie->sequence_number);
1033
1034         if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1035                 key->u.aes_cmac.replays++;
1036                 return RX_DROP_UNUSABLE;
1037         }
1038
1039         if (!(status->flag & RX_FLAG_DECRYPTED)) {
1040                 /* hardware didn't decrypt/verify MIC */
1041                 bip_aad(skb, aad);
1042                 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
1043                                    skb->data + 24, skb->len - 24, mic);
1044                 if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1045                         key->u.aes_cmac.icverrors++;
1046                         return RX_DROP_UNUSABLE;
1047                 }
1048         }
1049
1050         memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1051
1052         /* Remove MMIE */
1053         skb_trim(skb, skb->len - sizeof(*mmie));
1054
1055         return RX_CONTINUE;
1056 }
1057
1058 ieee80211_rx_result
1059 ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx)
1060 {
1061         struct sk_buff *skb = rx->skb;
1062         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1063         struct ieee80211_key *key = rx->key;
1064         struct ieee80211_mmie_16 *mmie;
1065         u8 aad[20], mic[16], ipn[6];
1066         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1067
1068         if (!ieee80211_is_mgmt(hdr->frame_control))
1069                 return RX_CONTINUE;
1070
1071         /* management frames are already linear */
1072
1073         if (skb->len < 24 + sizeof(*mmie))
1074                 return RX_DROP_UNUSABLE;
1075
1076         mmie = (struct ieee80211_mmie_16 *)
1077                 (skb->data + skb->len - sizeof(*mmie));
1078         if (mmie->element_id != WLAN_EID_MMIE ||
1079             mmie->length != sizeof(*mmie) - 2)
1080                 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1081
1082         bip_ipn_swap(ipn, mmie->sequence_number);
1083
1084         if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1085                 key->u.aes_cmac.replays++;
1086                 return RX_DROP_UNUSABLE;
1087         }
1088
1089         if (!(status->flag & RX_FLAG_DECRYPTED)) {
1090                 /* hardware didn't decrypt/verify MIC */
1091                 bip_aad(skb, aad);
1092                 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1093                                        skb->data + 24, skb->len - 24, mic);
1094                 if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1095                         key->u.aes_cmac.icverrors++;
1096                         return RX_DROP_UNUSABLE;
1097                 }
1098         }
1099
1100         memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1101
1102         /* Remove MMIE */
1103         skb_trim(skb, skb->len - sizeof(*mmie));
1104
1105         return RX_CONTINUE;
1106 }
1107
1108 ieee80211_tx_result
1109 ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx)
1110 {
1111         struct sk_buff *skb;
1112         struct ieee80211_tx_info *info;
1113         struct ieee80211_key *key = tx->key;
1114         struct ieee80211_mmie_16 *mmie;
1115         struct ieee80211_hdr *hdr;
1116         u8 aad[20];
1117         u64 pn64;
1118         u8 nonce[12];
1119
1120         if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
1121                 return TX_DROP;
1122
1123         skb = skb_peek(&tx->skbs);
1124
1125         info = IEEE80211_SKB_CB(skb);
1126
1127         if (info->control.hw_key)
1128                 return TX_CONTINUE;
1129
1130         if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
1131                 return TX_DROP;
1132
1133         mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie));
1134         mmie->element_id = WLAN_EID_MMIE;
1135         mmie->length = sizeof(*mmie) - 2;
1136         mmie->key_id = cpu_to_le16(key->conf.keyidx);
1137
1138         /* PN = PN + 1 */
1139         pn64 = atomic64_inc_return(&key->conf.tx_pn);
1140
1141         bip_ipn_set64(mmie->sequence_number, pn64);
1142
1143         bip_aad(skb, aad);
1144
1145         hdr = (struct ieee80211_hdr *)skb->data;
1146         memcpy(nonce, hdr->addr2, ETH_ALEN);
1147         bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number);
1148
1149         /* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */
1150         if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1151                                skb->data + 24, skb->len - 24, mmie->mic) < 0)
1152                 return TX_DROP;
1153
1154         return TX_CONTINUE;
1155 }
1156
1157 ieee80211_rx_result
1158 ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx)
1159 {
1160         struct sk_buff *skb = rx->skb;
1161         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1162         struct ieee80211_key *key = rx->key;
1163         struct ieee80211_mmie_16 *mmie;
1164         u8 aad[20], mic[16], ipn[6], nonce[12];
1165         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1166
1167         if (!ieee80211_is_mgmt(hdr->frame_control))
1168                 return RX_CONTINUE;
1169
1170         /* management frames are already linear */
1171
1172         if (skb->len < 24 + sizeof(*mmie))
1173                 return RX_DROP_UNUSABLE;
1174
1175         mmie = (struct ieee80211_mmie_16 *)
1176                 (skb->data + skb->len - sizeof(*mmie));
1177         if (mmie->element_id != WLAN_EID_MMIE ||
1178             mmie->length != sizeof(*mmie) - 2)
1179                 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1180
1181         bip_ipn_swap(ipn, mmie->sequence_number);
1182
1183         if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) {
1184                 key->u.aes_gmac.replays++;
1185                 return RX_DROP_UNUSABLE;
1186         }
1187
1188         if (!(status->flag & RX_FLAG_DECRYPTED)) {
1189                 /* hardware didn't decrypt/verify MIC */
1190                 bip_aad(skb, aad);
1191
1192                 memcpy(nonce, hdr->addr2, ETH_ALEN);
1193                 memcpy(nonce + ETH_ALEN, ipn, 6);
1194
1195                 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1196                                        skb->data + 24, skb->len - 24,
1197                                        mic) < 0 ||
1198                     memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1199                         key->u.aes_gmac.icverrors++;
1200                         return RX_DROP_UNUSABLE;
1201                 }
1202         }
1203
1204         memcpy(key->u.aes_gmac.rx_pn, ipn, 6);
1205
1206         /* Remove MMIE */
1207         skb_trim(skb, skb->len - sizeof(*mmie));
1208
1209         return RX_CONTINUE;
1210 }
1211
1212 ieee80211_tx_result
1213 ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx)
1214 {
1215         struct sk_buff *skb;
1216         struct ieee80211_tx_info *info = NULL;
1217         ieee80211_tx_result res;
1218
1219         skb_queue_walk(&tx->skbs, skb) {
1220                 info  = IEEE80211_SKB_CB(skb);
1221
1222                 /* handle hw-only algorithm */
1223                 if (!info->control.hw_key)
1224                         return TX_DROP;
1225
1226                 if (tx->key->flags & KEY_FLAG_CIPHER_SCHEME) {
1227                         res = ieee80211_crypto_cs_encrypt(tx, skb);
1228                         if (res != TX_CONTINUE)
1229                                 return res;
1230                 }
1231         }
1232
1233         ieee80211_tx_set_protected(tx);
1234
1235         return TX_CONTINUE;
1236 }
1237
1238 ieee80211_rx_result
1239 ieee80211_crypto_hw_decrypt(struct ieee80211_rx_data *rx)
1240 {
1241         if (rx->sta && rx->sta->cipher_scheme)
1242                 return ieee80211_crypto_cs_decrypt(rx);
1243
1244         return RX_DROP_UNUSABLE;
1245 }