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[CCM_AAD_LEN];
 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         return ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, b_0, aad, pos, len,
 465                                          skb_put(skb, mic_len), mic_len);
 466 }
 467
 468
 469 ieee80211_tx_result
 470 ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx,
 471                               unsigned int mic_len)
 472 {
 473         struct sk_buff *skb;
 474
 475         ieee80211_tx_set_protected(tx);
 476
 477         skb_queue_walk(&tx->skbs, skb) {
 478                 if (ccmp_encrypt_skb(tx, skb, mic_len) < 0)
 479                         return TX_DROP;
 480         }
 481
 482         return TX_CONTINUE;
 483 }
 484
 485
 486 ieee80211_rx_result
 487 ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx,
 488                               unsigned int mic_len)
 489 {
 490         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 491         int hdrlen;
 492         struct ieee80211_key *key = rx->key;
 493         struct sk_buff *skb = rx->skb;
 494         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 495         u8 pn[IEEE80211_CCMP_PN_LEN];
 496         int data_len;
 497         int queue;
 498
 499         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 500
 501         if (!ieee80211_is_data(hdr->frame_control) &&
 502             !ieee80211_is_robust_mgmt_frame(skb))
 503                 return RX_CONTINUE;
 504
 505         if (status->flag & RX_FLAG_DECRYPTED) {
 506                 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_CCMP_HDR_LEN))
 507                         return RX_DROP_UNUSABLE;
 508                 if (status->flag & RX_FLAG_MIC_STRIPPED)
 509                         mic_len = 0;
 510         } else {
 511                 if (skb_linearize(rx->skb))
 512                         return RX_DROP_UNUSABLE;
 513         }
 514
 515         data_len = skb->len - hdrlen - IEEE80211_CCMP_HDR_LEN - mic_len;
 516         if (!rx->sta || data_len < 0)
 517                 return RX_DROP_UNUSABLE;
 518
 519         if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
 520                 int res;
 521
 522                 ccmp_hdr2pn(pn, skb->data + hdrlen);
 523
 524                 queue = rx->security_idx;
 525
 526                 res = memcmp(pn, key->u.ccmp.rx_pn[queue],
 527                              IEEE80211_CCMP_PN_LEN);
 528                 if (res < 0 ||
 529                     (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
 530                         key->u.ccmp.replays++;
 531                         return RX_DROP_UNUSABLE;
 532                 }
 533
 534                 if (!(status->flag & RX_FLAG_DECRYPTED)) {
 535                         u8 aad[2 * AES_BLOCK_SIZE];
 536                         u8 b_0[AES_BLOCK_SIZE];
 537                         /* hardware didn't decrypt/verify MIC */
 538                         ccmp_special_blocks(skb, pn, b_0, aad);
 539
 540                         if (ieee80211_aes_ccm_decrypt(
 541                                     key->u.ccmp.tfm, b_0, aad,
 542                                     skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN,
 543                                     data_len,
 544                                     skb->data + skb->len - mic_len, mic_len))
 545                                 return RX_DROP_UNUSABLE;
 546                 }
 547
 548                 memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN);
 549         }
 550
 551         /* Remove CCMP header and MIC */
 552         if (pskb_trim(skb, skb->len - mic_len))
 553                 return RX_DROP_UNUSABLE;
 554         memmove(skb->data + IEEE80211_CCMP_HDR_LEN, skb->data, hdrlen);
 555         skb_pull(skb, IEEE80211_CCMP_HDR_LEN);
 556
 557         return RX_CONTINUE;
 558 }
 559
 560 static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad)
 561 {
 562         __le16 mask_fc;
 563         u8 qos_tid;
 564         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 565
 566         memcpy(j_0, hdr->addr2, ETH_ALEN);
 567         memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN);
 568         j_0[13] = 0;
 569         j_0[14] = 0;
 570         j_0[AES_BLOCK_SIZE - 1] = 0x01;
 571
 572         /* AAD (extra authenticate-only data) / masked 802.11 header
 573          * FC | A1 | A2 | A3 | SC | [A4] | [QC]
 574          */
 575         put_unaligned_be16(ieee80211_hdrlen(hdr->frame_control) - 2, &aad[0]);
 576         /* Mask FC: zero subtype b4 b5 b6 (if not mgmt)
 577          * Retry, PwrMgt, MoreData; set Protected
 578          */
 579         mask_fc = hdr->frame_control;
 580         mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
 581                                 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
 582         if (!ieee80211_is_mgmt(hdr->frame_control))
 583                 mask_fc &= ~cpu_to_le16(0x0070);
 584         mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
 585
 586         put_unaligned(mask_fc, (__le16 *)&aad[2]);
 587         memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
 588
 589         /* Mask Seq#, leave Frag# */
 590         aad[22] = *((u8 *)&hdr->seq_ctrl) & 0x0f;
 591         aad[23] = 0;
 592
 593         if (ieee80211_is_data_qos(hdr->frame_control))
 594                 qos_tid = *ieee80211_get_qos_ctl(hdr) &
 595                         IEEE80211_QOS_CTL_TID_MASK;
 596         else
 597                 qos_tid = 0;
 598
 599         if (ieee80211_has_a4(hdr->frame_control)) {
 600                 memcpy(&aad[24], hdr->addr4, ETH_ALEN);
 601                 aad[30] = qos_tid;
 602                 aad[31] = 0;
 603         } else {
 604                 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
 605                 aad[24] = qos_tid;
 606         }
 607 }
 608
 609 static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id)
 610 {
 611         hdr[0] = pn[5];
 612         hdr[1] = pn[4];
 613         hdr[2] = 0;
 614         hdr[3] = 0x20 | (key_id << 6);
 615         hdr[4] = pn[3];
 616         hdr[5] = pn[2];
 617         hdr[6] = pn[1];
 618         hdr[7] = pn[0];
 619 }
 620
 621 static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr)
 622 {
 623         pn[0] = hdr[7];
 624         pn[1] = hdr[6];
 625         pn[2] = hdr[5];
 626         pn[3] = hdr[4];
 627         pn[4] = hdr[1];
 628         pn[5] = hdr[0];
 629 }
 630
 631 static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
 632 {
 633         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 634         struct ieee80211_key *key = tx->key;
 635         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 636         int hdrlen, len, tail;
 637         u8 *pos;
 638         u8 pn[6];
 639         u64 pn64;
 640         u8 aad[GCM_AAD_LEN];
 641         u8 j_0[AES_BLOCK_SIZE];
 642
 643         if (info->control.hw_key &&
 644             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 645             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 646             !((info->control.hw_key->flags &
 647                IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
 648               ieee80211_is_mgmt(hdr->frame_control))) {
 649                 /* hwaccel has no need for preallocated room for GCMP
 650                  * header or MIC fields
 651                  */
 652                 return 0;
 653         }
 654
 655         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 656         len = skb->len - hdrlen;
 657
 658         if (info->control.hw_key)
 659                 tail = 0;
 660         else
 661                 tail = IEEE80211_GCMP_MIC_LEN;
 662
 663         if (WARN_ON(skb_tailroom(skb) < tail ||
 664                     skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN))
 665                 return -1;
 666
 667         pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN);
 668         memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen);
 669         skb_set_network_header(skb, skb_network_offset(skb) +
 670                                     IEEE80211_GCMP_HDR_LEN);
 671
 672         /* the HW only needs room for the IV, but not the actual IV */
 673         if (info->control.hw_key &&
 674             (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 675                 return 0;
 676
 677         hdr = (struct ieee80211_hdr *)pos;
 678         pos += hdrlen;
 679
 680         pn64 = atomic64_inc_return(&key->conf.tx_pn);
 681
 682         pn[5] = pn64;
 683         pn[4] = pn64 >> 8;
 684         pn[3] = pn64 >> 16;
 685         pn[2] = pn64 >> 24;
 686         pn[1] = pn64 >> 32;
 687         pn[0] = pn64 >> 40;
 688
 689         gcmp_pn2hdr(pos, pn, key->conf.keyidx);
 690
 691         /* hwaccel - with software GCMP header */
 692         if (info->control.hw_key)
 693                 return 0;
 694
 695         pos += IEEE80211_GCMP_HDR_LEN;
 696         gcmp_special_blocks(skb, pn, j_0, aad);
 697         return ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len,
 698                                          skb_put(skb, IEEE80211_GCMP_MIC_LEN));
 699 }
 700
 701 ieee80211_tx_result
 702 ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx)
 703 {
 704         struct sk_buff *skb;
 705
 706         ieee80211_tx_set_protected(tx);
 707
 708         skb_queue_walk(&tx->skbs, skb) {
 709                 if (gcmp_encrypt_skb(tx, skb) < 0)
 710                         return TX_DROP;
 711         }
 712
 713         return TX_CONTINUE;
 714 }
 715
 716 ieee80211_rx_result
 717 ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
 718 {
 719         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 720         int hdrlen;
 721         struct ieee80211_key *key = rx->key;
 722         struct sk_buff *skb = rx->skb;
 723         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 724         u8 pn[IEEE80211_GCMP_PN_LEN];
 725         int data_len, queue, mic_len = IEEE80211_GCMP_MIC_LEN;
 726
 727         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 728
 729         if (!ieee80211_is_data(hdr->frame_control) &&
 730             !ieee80211_is_robust_mgmt_frame(skb))
 731                 return RX_CONTINUE;
 732
 733         if (status->flag & RX_FLAG_DECRYPTED) {
 734                 if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN))
 735                         return RX_DROP_UNUSABLE;
 736                 if (status->flag & RX_FLAG_MIC_STRIPPED)
 737                         mic_len = 0;
 738         } else {
 739                 if (skb_linearize(rx->skb))
 740                         return RX_DROP_UNUSABLE;
 741         }
 742
 743         data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN - mic_len;
 744         if (!rx->sta || data_len < 0)
 745                 return RX_DROP_UNUSABLE;
 746
 747         if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
 748                 int res;
 749
 750                 gcmp_hdr2pn(pn, skb->data + hdrlen);
 751
 752                 queue = rx->security_idx;
 753
 754                 res = memcmp(pn, key->u.gcmp.rx_pn[queue],
 755                              IEEE80211_GCMP_PN_LEN);
 756                 if (res < 0 ||
 757                     (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
 758                         key->u.gcmp.replays++;
 759                         return RX_DROP_UNUSABLE;
 760                 }
 761
 762                 if (!(status->flag & RX_FLAG_DECRYPTED)) {
 763                         u8 aad[2 * AES_BLOCK_SIZE];
 764                         u8 j_0[AES_BLOCK_SIZE];
 765                         /* hardware didn't decrypt/verify MIC */
 766                         gcmp_special_blocks(skb, pn, j_0, aad);
 767
 768                         if (ieee80211_aes_gcm_decrypt(
 769                                     key->u.gcmp.tfm, j_0, aad,
 770                                     skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN,
 771                                     data_len,
 772                                     skb->data + skb->len -
 773                                     IEEE80211_GCMP_MIC_LEN))
 774                                 return RX_DROP_UNUSABLE;
 775                 }
 776
 777                 memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN);
 778         }
 779
 780         /* Remove GCMP header and MIC */
 781         if (pskb_trim(skb, skb->len - mic_len))
 782                 return RX_DROP_UNUSABLE;
 783         memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen);
 784         skb_pull(skb, IEEE80211_GCMP_HDR_LEN);
 785
 786         return RX_CONTINUE;
 787 }
 788
 789 static ieee80211_tx_result
 790 ieee80211_crypto_cs_encrypt(struct ieee80211_tx_data *tx,
 791                             struct sk_buff *skb)
 792 {
 793         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 794         struct ieee80211_key *key = tx->key;
 795         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 796         int hdrlen;
 797         u8 *pos, iv_len = key->conf.iv_len;
 798
 799         if (info->control.hw_key &&
 800             !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
 801                 /* hwaccel has no need for preallocated head room */
 802                 return TX_CONTINUE;
 803         }
 804
 805         if (unlikely(skb_headroom(skb) < iv_len &&
 806                      pskb_expand_head(skb, iv_len, 0, GFP_ATOMIC)))
 807                 return TX_DROP;
 808
 809         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 810
 811         pos = skb_push(skb, iv_len);
 812         memmove(pos, pos + iv_len, hdrlen);
 813
 814         return TX_CONTINUE;
 815 }
 816
 817 static inline int ieee80211_crypto_cs_pn_compare(u8 *pn1, u8 *pn2, int len)
 818 {
 819         int i;
 820
 821         /* pn is little endian */
 822         for (i = len - 1; i >= 0; i--) {
 823                 if (pn1[i] < pn2[i])
 824                         return -1;
 825                 else if (pn1[i] > pn2[i])
 826                         return 1;
 827         }
 828
 829         return 0;
 830 }
 831
 832 static ieee80211_rx_result
 833 ieee80211_crypto_cs_decrypt(struct ieee80211_rx_data *rx)
 834 {
 835         struct ieee80211_key *key = rx->key;
 836         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 837         const struct ieee80211_cipher_scheme *cs = NULL;
 838         int hdrlen = ieee80211_hdrlen(hdr->frame_control);
 839         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 840         int data_len;
 841         u8 *rx_pn;
 842         u8 *skb_pn;
 843         u8 qos_tid;
 844
 845         if (!rx->sta || !rx->sta->cipher_scheme ||
 846             !(status->flag & RX_FLAG_DECRYPTED))
 847                 return RX_DROP_UNUSABLE;
 848
 849         if (!ieee80211_is_data(hdr->frame_control))
 850                 return RX_CONTINUE;
 851
 852         cs = rx->sta->cipher_scheme;
 853
 854         data_len = rx->skb->len - hdrlen - cs->hdr_len;
 855
 856         if (data_len < 0)
 857                 return RX_DROP_UNUSABLE;
 858
 859         if (ieee80211_is_data_qos(hdr->frame_control))
 860                 qos_tid = *ieee80211_get_qos_ctl(hdr) &
 861                                 IEEE80211_QOS_CTL_TID_MASK;
 862         else
 863                 qos_tid = 0;
 864
 865         if (skb_linearize(rx->skb))
 866                 return RX_DROP_UNUSABLE;
 867
 868         hdr = (struct ieee80211_hdr *)rx->skb->data;
 869
 870         rx_pn = key->u.gen.rx_pn[qos_tid];
 871         skb_pn = rx->skb->data + hdrlen + cs->pn_off;
 872
 873         if (ieee80211_crypto_cs_pn_compare(skb_pn, rx_pn, cs->pn_len) <= 0)
 874                 return RX_DROP_UNUSABLE;
 875
 876         memcpy(rx_pn, skb_pn, cs->pn_len);
 877
 878         /* remove security header and MIC */
 879         if (pskb_trim(rx->skb, rx->skb->len - cs->mic_len))
 880                 return RX_DROP_UNUSABLE;
 881
 882         memmove(rx->skb->data + cs->hdr_len, rx->skb->data, hdrlen);
 883         skb_pull(rx->skb, cs->hdr_len);
 884
 885         return RX_CONTINUE;
 886 }
 887
 888 static void bip_aad(struct sk_buff *skb, u8 *aad)
 889 {
 890         __le16 mask_fc;
 891         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 892
 893         /* BIP AAD: FC(masked) || A1 || A2 || A3 */
 894
 895         /* FC type/subtype */
 896         /* Mask FC Retry, PwrMgt, MoreData flags to zero */
 897         mask_fc = hdr->frame_control;
 898         mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM |
 899                                 IEEE80211_FCTL_MOREDATA);
 900         put_unaligned(mask_fc, (__le16 *) &aad[0]);
 901         /* A1 || A2 || A3 */
 902         memcpy(aad + 2, &hdr->addr1, 3 * ETH_ALEN);
 903 }
 904
 905
 906 static inline void bip_ipn_set64(u8 *d, u64 pn)
 907 {
 908         *d++ = pn;
 909         *d++ = pn >> 8;
 910         *d++ = pn >> 16;
 911         *d++ = pn >> 24;
 912         *d++ = pn >> 32;
 913         *d = pn >> 40;
 914 }
 915
 916 static inline void bip_ipn_swap(u8 *d, const u8 *s)
 917 {
 918         *d++ = s[5];
 919         *d++ = s[4];
 920         *d++ = s[3];
 921         *d++ = s[2];
 922         *d++ = s[1];
 923         *d = s[0];
 924 }
 925
 926
 927 ieee80211_tx_result
 928 ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
 929 {
 930         struct sk_buff *skb;
 931         struct ieee80211_tx_info *info;
 932         struct ieee80211_key *key = tx->key;
 933         struct ieee80211_mmie *mmie;
 934         u8 aad[20];
 935         u64 pn64;
 936
 937         if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
 938                 return TX_DROP;
 939
 940         skb = skb_peek(&tx->skbs);
 941
 942         info = IEEE80211_SKB_CB(skb);
 943
 944         if (info->control.hw_key)
 945                 return TX_CONTINUE;
 946
 947         if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
 948                 return TX_DROP;
 949
 950         mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie));
 951         mmie->element_id = WLAN_EID_MMIE;
 952         mmie->length = sizeof(*mmie) - 2;
 953         mmie->key_id = cpu_to_le16(key->conf.keyidx);
 954
 955         /* PN = PN + 1 */
 956         pn64 = atomic64_inc_return(&key->conf.tx_pn);
 957
 958         bip_ipn_set64(mmie->sequence_number, pn64);
 959
 960         bip_aad(skb, aad);
 961
 962         /*
 963          * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
 964          */
 965         ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
 966                            skb->data + 24, skb->len - 24, mmie->mic);
 967
 968         return TX_CONTINUE;
 969 }
 970
 971 ieee80211_tx_result
 972 ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx)
 973 {
 974         struct sk_buff *skb;
 975         struct ieee80211_tx_info *info;
 976         struct ieee80211_key *key = tx->key;
 977         struct ieee80211_mmie_16 *mmie;
 978         u8 aad[20];
 979         u64 pn64;
 980
 981         if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
 982                 return TX_DROP;
 983
 984         skb = skb_peek(&tx->skbs);
 985
 986         info = IEEE80211_SKB_CB(skb);
 987
 988         if (info->control.hw_key)
 989                 return TX_CONTINUE;
 990
 991         if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
 992                 return TX_DROP;
 993
 994         mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie));
 995         mmie->element_id = WLAN_EID_MMIE;
 996         mmie->length = sizeof(*mmie) - 2;
 997         mmie->key_id = cpu_to_le16(key->conf.keyidx);
 998
 999         /* PN = PN + 1 */
1000         pn64 = atomic64_inc_return(&key->conf.tx_pn);
1001
1002         bip_ipn_set64(mmie->sequence_number, pn64);
1003
1004         bip_aad(skb, aad);
1005
1006         /* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128)
1007          */
1008         ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1009                                skb->data + 24, skb->len - 24, mmie->mic);
1010
1011         return TX_CONTINUE;
1012 }
1013
1014 ieee80211_rx_result
1015 ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
1016 {
1017         struct sk_buff *skb = rx->skb;
1018         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1019         struct ieee80211_key *key = rx->key;
1020         struct ieee80211_mmie *mmie;
1021         u8 aad[20], mic[8], ipn[6];
1022         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1023
1024         if (!ieee80211_is_mgmt(hdr->frame_control))
1025                 return RX_CONTINUE;
1026
1027         /* management frames are already linear */
1028
1029         if (skb->len < 24 + sizeof(*mmie))
1030                 return RX_DROP_UNUSABLE;
1031
1032         mmie = (struct ieee80211_mmie *)
1033                 (skb->data + skb->len - sizeof(*mmie));
1034         if (mmie->element_id != WLAN_EID_MMIE ||
1035             mmie->length != sizeof(*mmie) - 2)
1036                 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1037
1038         bip_ipn_swap(ipn, mmie->sequence_number);
1039
1040         if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1041                 key->u.aes_cmac.replays++;
1042                 return RX_DROP_UNUSABLE;
1043         }
1044
1045         if (!(status->flag & RX_FLAG_DECRYPTED)) {
1046                 /* hardware didn't decrypt/verify MIC */
1047                 bip_aad(skb, aad);
1048                 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
1049                                    skb->data + 24, skb->len - 24, mic);
1050                 if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1051                         key->u.aes_cmac.icverrors++;
1052                         return RX_DROP_UNUSABLE;
1053                 }
1054         }
1055
1056         memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1057
1058         /* Remove MMIE */
1059         skb_trim(skb, skb->len - sizeof(*mmie));
1060
1061         return RX_CONTINUE;
1062 }
1063
1064 ieee80211_rx_result
1065 ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx)
1066 {
1067         struct sk_buff *skb = rx->skb;
1068         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1069         struct ieee80211_key *key = rx->key;
1070         struct ieee80211_mmie_16 *mmie;
1071         u8 aad[20], mic[16], ipn[6];
1072         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1073
1074         if (!ieee80211_is_mgmt(hdr->frame_control))
1075                 return RX_CONTINUE;
1076
1077         /* management frames are already linear */
1078
1079         if (skb->len < 24 + sizeof(*mmie))
1080                 return RX_DROP_UNUSABLE;
1081
1082         mmie = (struct ieee80211_mmie_16 *)
1083                 (skb->data + skb->len - sizeof(*mmie));
1084         if (mmie->element_id != WLAN_EID_MMIE ||
1085             mmie->length != sizeof(*mmie) - 2)
1086                 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1087
1088         bip_ipn_swap(ipn, mmie->sequence_number);
1089
1090         if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1091                 key->u.aes_cmac.replays++;
1092                 return RX_DROP_UNUSABLE;
1093         }
1094
1095         if (!(status->flag & RX_FLAG_DECRYPTED)) {
1096                 /* hardware didn't decrypt/verify MIC */
1097                 bip_aad(skb, aad);
1098                 ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1099                                        skb->data + 24, skb->len - 24, mic);
1100                 if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1101                         key->u.aes_cmac.icverrors++;
1102                         return RX_DROP_UNUSABLE;
1103                 }
1104         }
1105
1106         memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1107
1108         /* Remove MMIE */
1109         skb_trim(skb, skb->len - sizeof(*mmie));
1110
1111         return RX_CONTINUE;
1112 }
1113
1114 ieee80211_tx_result
1115 ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx)
1116 {
1117         struct sk_buff *skb;
1118         struct ieee80211_tx_info *info;
1119         struct ieee80211_key *key = tx->key;
1120         struct ieee80211_mmie_16 *mmie;
1121         struct ieee80211_hdr *hdr;
1122         u8 aad[GMAC_AAD_LEN];
1123         u64 pn64;
1124         u8 nonce[GMAC_NONCE_LEN];
1125
1126         if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
1127                 return TX_DROP;
1128
1129         skb = skb_peek(&tx->skbs);
1130
1131         info = IEEE80211_SKB_CB(skb);
1132
1133         if (info->control.hw_key)
1134                 return TX_CONTINUE;
1135
1136         if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
1137                 return TX_DROP;
1138
1139         mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie));
1140         mmie->element_id = WLAN_EID_MMIE;
1141         mmie->length = sizeof(*mmie) - 2;
1142         mmie->key_id = cpu_to_le16(key->conf.keyidx);
1143
1144         /* PN = PN + 1 */
1145         pn64 = atomic64_inc_return(&key->conf.tx_pn);
1146
1147         bip_ipn_set64(mmie->sequence_number, pn64);
1148
1149         bip_aad(skb, aad);
1150
1151         hdr = (struct ieee80211_hdr *)skb->data;
1152         memcpy(nonce, hdr->addr2, ETH_ALEN);
1153         bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number);
1154
1155         /* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */
1156         if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1157                                skb->data + 24, skb->len - 24, mmie->mic) < 0)
1158                 return TX_DROP;
1159
1160         return TX_CONTINUE;
1161 }
1162
1163 ieee80211_rx_result
1164 ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx)
1165 {
1166         struct sk_buff *skb = rx->skb;
1167         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1168         struct ieee80211_key *key = rx->key;
1169         struct ieee80211_mmie_16 *mmie;
1170         u8 aad[GMAC_AAD_LEN], mic[GMAC_MIC_LEN], ipn[6], nonce[GMAC_NONCE_LEN];
1171         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1172
1173         if (!ieee80211_is_mgmt(hdr->frame_control))
1174                 return RX_CONTINUE;
1175
1176         /* management frames are already linear */
1177
1178         if (skb->len < 24 + sizeof(*mmie))
1179                 return RX_DROP_UNUSABLE;
1180
1181         mmie = (struct ieee80211_mmie_16 *)
1182                 (skb->data + skb->len - sizeof(*mmie));
1183         if (mmie->element_id != WLAN_EID_MMIE ||
1184             mmie->length != sizeof(*mmie) - 2)
1185                 return RX_DROP_UNUSABLE; /* Invalid MMIE */
1186
1187         bip_ipn_swap(ipn, mmie->sequence_number);
1188
1189         if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) {
1190                 key->u.aes_gmac.replays++;
1191                 return RX_DROP_UNUSABLE;
1192         }
1193
1194         if (!(status->flag & RX_FLAG_DECRYPTED)) {
1195                 /* hardware didn't decrypt/verify MIC */
1196                 bip_aad(skb, aad);
1197
1198                 memcpy(nonce, hdr->addr2, ETH_ALEN);
1199                 memcpy(nonce + ETH_ALEN, ipn, 6);
1200
1201                 if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1202                                        skb->data + 24, skb->len - 24,
1203                                        mic) < 0 ||
1204                     memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1205                         key->u.aes_gmac.icverrors++;
1206                         return RX_DROP_UNUSABLE;
1207                 }
1208         }
1209
1210         memcpy(key->u.aes_gmac.rx_pn, ipn, 6);
1211
1212         /* Remove MMIE */
1213         skb_trim(skb, skb->len - sizeof(*mmie));
1214
1215         return RX_CONTINUE;
1216 }
1217
1218 ieee80211_tx_result
1219 ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx)
1220 {
1221         struct sk_buff *skb;
1222         struct ieee80211_tx_info *info = NULL;
1223         ieee80211_tx_result res;
1224
1225         skb_queue_walk(&tx->skbs, skb) {
1226                 info  = IEEE80211_SKB_CB(skb);
1227
1228                 /* handle hw-only algorithm */
1229                 if (!info->control.hw_key)
1230                         return TX_DROP;
1231
1232                 if (tx->key->flags & KEY_FLAG_CIPHER_SCHEME) {
1233                         res = ieee80211_crypto_cs_encrypt(tx, skb);
1234                         if (res != TX_CONTINUE)
1235                                 return res;
1236                 }
1237         }
1238
1239         ieee80211_tx_set_protected(tx);
1240
1241         return TX_CONTINUE;
1242 }
1243
1244 ieee80211_rx_result
1245 ieee80211_crypto_hw_decrypt(struct ieee80211_rx_data *rx)
1246 {
1247         if (rx->sta && rx->sta->cipher_scheme)
1248                 return ieee80211_crypto_cs_decrypt(rx);
1249
1250         return RX_DROP_UNUSABLE;
1251 }