linux/net/mac80211/wpa.c
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   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
  30ieee80211_tx_result
  31ieee80211_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
  87ieee80211_rx_result
  88ieee80211_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
 162update_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
 169mic_fail:
 170        rx->key->u.tkip.mic_failures++;
 171
 172mic_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
 187static 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
 241ieee80211_tx_result
 242ieee80211_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
 257ieee80211_rx_result
 258ieee80211_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
 307static 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
 374static 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
 387static 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
 398static 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
 471ieee80211_tx_result
 472ieee80211_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
 488ieee80211_rx_result
 489ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx,
 490                              unsigned int mic_len)
 491{
 492        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 493        int hdrlen;
 494        struct ieee80211_key *key = rx->key;
 495        struct sk_buff *skb = rx->skb;
 496        struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 497        u8 pn[IEEE80211_CCMP_PN_LEN];
 498        int data_len;
 499        int queue;
 500
 501        hdrlen = ieee80211_hdrlen(hdr->frame_control);
 502
 503        if (!ieee80211_is_data(hdr->frame_control) &&
 504            !ieee80211_is_robust_mgmt_frame(skb))
 505                return RX_CONTINUE;
 506
 507        if (status->flag & RX_FLAG_DECRYPTED) {
 508                if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_CCMP_HDR_LEN))
 509                        return RX_DROP_UNUSABLE;
 510                if (status->flag & RX_FLAG_MIC_STRIPPED)
 511                        mic_len = 0;
 512        } else {
 513                if (skb_linearize(rx->skb))
 514                        return RX_DROP_UNUSABLE;
 515        }
 516
 517        data_len = skb->len - hdrlen - IEEE80211_CCMP_HDR_LEN - mic_len;
 518        if (!rx->sta || data_len < 0)
 519                return RX_DROP_UNUSABLE;
 520
 521        if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
 522                int res;
 523
 524                ccmp_hdr2pn(pn, skb->data + hdrlen);
 525
 526                queue = rx->security_idx;
 527
 528                res = memcmp(pn, key->u.ccmp.rx_pn[queue],
 529                             IEEE80211_CCMP_PN_LEN);
 530                if (res < 0 ||
 531                    (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
 532                        key->u.ccmp.replays++;
 533                        return RX_DROP_UNUSABLE;
 534                }
 535
 536                if (!(status->flag & RX_FLAG_DECRYPTED)) {
 537                        u8 aad[2 * AES_BLOCK_SIZE];
 538                        u8 b_0[AES_BLOCK_SIZE];
 539                        /* hardware didn't decrypt/verify MIC */
 540                        ccmp_special_blocks(skb, pn, b_0, aad);
 541
 542                        if (ieee80211_aes_ccm_decrypt(
 543                                    key->u.ccmp.tfm, b_0, aad,
 544                                    skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN,
 545                                    data_len,
 546                                    skb->data + skb->len - mic_len, mic_len))
 547                                return RX_DROP_UNUSABLE;
 548                }
 549
 550                memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN);
 551        }
 552
 553        /* Remove CCMP header and MIC */
 554        if (pskb_trim(skb, skb->len - mic_len))
 555                return RX_DROP_UNUSABLE;
 556        memmove(skb->data + IEEE80211_CCMP_HDR_LEN, skb->data, hdrlen);
 557        skb_pull(skb, IEEE80211_CCMP_HDR_LEN);
 558
 559        return RX_CONTINUE;
 560}
 561
 562static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad)
 563{
 564        __le16 mask_fc;
 565        u8 qos_tid;
 566        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 567
 568        memcpy(j_0, hdr->addr2, ETH_ALEN);
 569        memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN);
 570        j_0[13] = 0;
 571        j_0[14] = 0;
 572        j_0[AES_BLOCK_SIZE - 1] = 0x01;
 573
 574        /* AAD (extra authenticate-only data) / masked 802.11 header
 575         * FC | A1 | A2 | A3 | SC | [A4] | [QC]
 576         */
 577        put_unaligned_be16(ieee80211_hdrlen(hdr->frame_control) - 2, &aad[0]);
 578        /* Mask FC: zero subtype b4 b5 b6 (if not mgmt)
 579         * Retry, PwrMgt, MoreData; set Protected
 580         */
 581        mask_fc = hdr->frame_control;
 582        mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
 583                                IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
 584        if (!ieee80211_is_mgmt(hdr->frame_control))
 585                mask_fc &= ~cpu_to_le16(0x0070);
 586        mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
 587
 588        put_unaligned(mask_fc, (__le16 *)&aad[2]);
 589        memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
 590
 591        /* Mask Seq#, leave Frag# */
 592        aad[22] = *((u8 *)&hdr->seq_ctrl) & 0x0f;
 593        aad[23] = 0;
 594
 595        if (ieee80211_is_data_qos(hdr->frame_control))
 596                qos_tid = *ieee80211_get_qos_ctl(hdr) &
 597                        IEEE80211_QOS_CTL_TID_MASK;
 598        else
 599                qos_tid = 0;
 600
 601        if (ieee80211_has_a4(hdr->frame_control)) {
 602                memcpy(&aad[24], hdr->addr4, ETH_ALEN);
 603                aad[30] = qos_tid;
 604                aad[31] = 0;
 605        } else {
 606                memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
 607                aad[24] = qos_tid;
 608        }
 609}
 610
 611static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id)
 612{
 613        hdr[0] = pn[5];
 614        hdr[1] = pn[4];
 615        hdr[2] = 0;
 616        hdr[3] = 0x20 | (key_id << 6);
 617        hdr[4] = pn[3];
 618        hdr[5] = pn[2];
 619        hdr[6] = pn[1];
 620        hdr[7] = pn[0];
 621}
 622
 623static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr)
 624{
 625        pn[0] = hdr[7];
 626        pn[1] = hdr[6];
 627        pn[2] = hdr[5];
 628        pn[3] = hdr[4];
 629        pn[4] = hdr[1];
 630        pn[5] = hdr[0];
 631}
 632
 633static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
 634{
 635        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 636        struct ieee80211_key *key = tx->key;
 637        struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 638        int hdrlen, len, tail;
 639        u8 *pos;
 640        u8 pn[6];
 641        u64 pn64;
 642        u8 aad[2 * AES_BLOCK_SIZE];
 643        u8 j_0[AES_BLOCK_SIZE];
 644
 645        if (info->control.hw_key &&
 646            !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 647            !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 648            !((info->control.hw_key->flags &
 649               IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
 650              ieee80211_is_mgmt(hdr->frame_control))) {
 651                /* hwaccel has no need for preallocated room for GCMP
 652                 * header or MIC fields
 653                 */
 654                return 0;
 655        }
 656
 657        hdrlen = ieee80211_hdrlen(hdr->frame_control);
 658        len = skb->len - hdrlen;
 659
 660        if (info->control.hw_key)
 661                tail = 0;
 662        else
 663                tail = IEEE80211_GCMP_MIC_LEN;
 664
 665        if (WARN_ON(skb_tailroom(skb) < tail ||
 666                    skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN))
 667                return -1;
 668
 669        pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN);
 670        memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen);
 671        skb_set_network_header(skb, skb_network_offset(skb) +
 672                                    IEEE80211_GCMP_HDR_LEN);
 673
 674        /* the HW only needs room for the IV, but not the actual IV */
 675        if (info->control.hw_key &&
 676            (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 677                return 0;
 678
 679        hdr = (struct ieee80211_hdr *)pos;
 680        pos += hdrlen;
 681
 682        pn64 = atomic64_inc_return(&key->conf.tx_pn);
 683
 684        pn[5] = pn64;
 685        pn[4] = pn64 >> 8;
 686        pn[3] = pn64 >> 16;
 687        pn[2] = pn64 >> 24;
 688        pn[1] = pn64 >> 32;
 689        pn[0] = pn64 >> 40;
 690
 691        gcmp_pn2hdr(pos, pn, key->conf.keyidx);
 692
 693        /* hwaccel - with software GCMP header */
 694        if (info->control.hw_key)
 695                return 0;
 696
 697        pos += IEEE80211_GCMP_HDR_LEN;
 698        gcmp_special_blocks(skb, pn, j_0, aad);
 699        ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len,
 700                                  skb_put(skb, IEEE80211_GCMP_MIC_LEN));
 701
 702        return 0;
 703}
 704
 705ieee80211_tx_result
 706ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx)
 707{
 708        struct sk_buff *skb;
 709
 710        ieee80211_tx_set_protected(tx);
 711
 712        skb_queue_walk(&tx->skbs, skb) {
 713                if (gcmp_encrypt_skb(tx, skb) < 0)
 714                        return TX_DROP;
 715        }
 716
 717        return TX_CONTINUE;
 718}
 719
 720ieee80211_rx_result
 721ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
 722{
 723        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 724        int hdrlen;
 725        struct ieee80211_key *key = rx->key;
 726        struct sk_buff *skb = rx->skb;
 727        struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 728        u8 pn[IEEE80211_GCMP_PN_LEN];
 729        int data_len, queue, mic_len = IEEE80211_GCMP_MIC_LEN;
 730
 731        hdrlen = ieee80211_hdrlen(hdr->frame_control);
 732
 733        if (!ieee80211_is_data(hdr->frame_control) &&
 734            !ieee80211_is_robust_mgmt_frame(skb))
 735                return RX_CONTINUE;
 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                if (status->flag & RX_FLAG_MIC_STRIPPED)
 741                        mic_len = 0;
 742        } else {
 743                if (skb_linearize(rx->skb))
 744                        return RX_DROP_UNUSABLE;
 745        }
 746
 747        data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN - mic_len;
 748        if (!rx->sta || data_len < 0)
 749                return RX_DROP_UNUSABLE;
 750
 751        if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
 752                int res;
 753
 754                gcmp_hdr2pn(pn, skb->data + hdrlen);
 755
 756                queue = rx->security_idx;
 757
 758                res = memcmp(pn, key->u.gcmp.rx_pn[queue],
 759                             IEEE80211_GCMP_PN_LEN);
 760                if (res < 0 ||
 761                    (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
 762                        key->u.gcmp.replays++;
 763                        return RX_DROP_UNUSABLE;
 764                }
 765
 766                if (!(status->flag & RX_FLAG_DECRYPTED)) {
 767                        u8 aad[2 * AES_BLOCK_SIZE];
 768                        u8 j_0[AES_BLOCK_SIZE];
 769                        /* hardware didn't decrypt/verify MIC */
 770                        gcmp_special_blocks(skb, pn, j_0, aad);
 771
 772                        if (ieee80211_aes_gcm_decrypt(
 773                                    key->u.gcmp.tfm, j_0, aad,
 774                                    skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN,
 775                                    data_len,
 776                                    skb->data + skb->len -
 777                                    IEEE80211_GCMP_MIC_LEN))
 778                                return RX_DROP_UNUSABLE;
 779                }
 780
 781                memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN);
 782        }
 783
 784        /* Remove GCMP header and MIC */
 785        if (pskb_trim(skb, skb->len - mic_len))
 786                return RX_DROP_UNUSABLE;
 787        memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen);
 788        skb_pull(skb, IEEE80211_GCMP_HDR_LEN);
 789
 790        return RX_CONTINUE;
 791}
 792
 793static ieee80211_tx_result
 794ieee80211_crypto_cs_encrypt(struct ieee80211_tx_data *tx,
 795                            struct sk_buff *skb)
 796{
 797        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 798        struct ieee80211_key *key = tx->key;
 799        struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 800        int hdrlen;
 801        u8 *pos, iv_len = key->conf.iv_len;
 802
 803        if (info->control.hw_key &&
 804            !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
 805                /* hwaccel has no need for preallocated head room */
 806                return TX_CONTINUE;
 807        }
 808
 809        if (unlikely(skb_headroom(skb) < iv_len &&
 810                     pskb_expand_head(skb, iv_len, 0, GFP_ATOMIC)))
 811                return TX_DROP;
 812
 813        hdrlen = ieee80211_hdrlen(hdr->frame_control);
 814
 815        pos = skb_push(skb, iv_len);
 816        memmove(pos, pos + iv_len, hdrlen);
 817
 818        return TX_CONTINUE;
 819}
 820
 821static inline int ieee80211_crypto_cs_pn_compare(u8 *pn1, u8 *pn2, int len)
 822{
 823        int i;
 824
 825        /* pn is little endian */
 826        for (i = len - 1; i >= 0; i--) {
 827                if (pn1[i] < pn2[i])
 828                        return -1;
 829                else if (pn1[i] > pn2[i])
 830                        return 1;
 831        }
 832
 833        return 0;
 834}
 835
 836static ieee80211_rx_result
 837ieee80211_crypto_cs_decrypt(struct ieee80211_rx_data *rx)
 838{
 839        struct ieee80211_key *key = rx->key;
 840        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 841        const struct ieee80211_cipher_scheme *cs = NULL;
 842        int hdrlen = ieee80211_hdrlen(hdr->frame_control);
 843        struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 844        int data_len;
 845        u8 *rx_pn;
 846        u8 *skb_pn;
 847        u8 qos_tid;
 848
 849        if (!rx->sta || !rx->sta->cipher_scheme ||
 850            !(status->flag & RX_FLAG_DECRYPTED))
 851                return RX_DROP_UNUSABLE;
 852
 853        if (!ieee80211_is_data(hdr->frame_control))
 854                return RX_CONTINUE;
 855
 856        cs = rx->sta->cipher_scheme;
 857
 858        data_len = rx->skb->len - hdrlen - cs->hdr_len;
 859
 860        if (data_len < 0)
 861                return RX_DROP_UNUSABLE;
 862
 863        if (ieee80211_is_data_qos(hdr->frame_control))
 864                qos_tid = *ieee80211_get_qos_ctl(hdr) &
 865                                IEEE80211_QOS_CTL_TID_MASK;
 866        else
 867                qos_tid = 0;
 868
 869        if (skb_linearize(rx->skb))
 870                return RX_DROP_UNUSABLE;
 871
 872        hdr = (struct ieee80211_hdr *)rx->skb->data;
 873
 874        rx_pn = key->u.gen.rx_pn[qos_tid];
 875        skb_pn = rx->skb->data + hdrlen + cs->pn_off;
 876
 877        if (ieee80211_crypto_cs_pn_compare(skb_pn, rx_pn, cs->pn_len) <= 0)
 878                return RX_DROP_UNUSABLE;
 879
 880        memcpy(rx_pn, skb_pn, cs->pn_len);
 881
 882        /* remove security header and MIC */
 883        if (pskb_trim(rx->skb, rx->skb->len - cs->mic_len))
 884                return RX_DROP_UNUSABLE;
 885
 886        memmove(rx->skb->data + cs->hdr_len, rx->skb->data, hdrlen);
 887        skb_pull(rx->skb, cs->hdr_len);
 888
 889        return RX_CONTINUE;
 890}
 891
 892static void bip_aad(struct sk_buff *skb, u8 *aad)
 893{
 894        __le16 mask_fc;
 895        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 896
 897        /* BIP AAD: FC(masked) || A1 || A2 || A3 */
 898
 899        /* FC type/subtype */
 900        /* Mask FC Retry, PwrMgt, MoreData flags to zero */
 901        mask_fc = hdr->frame_control;
 902        mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM |
 903                                IEEE80211_FCTL_MOREDATA);
 904        put_unaligned(mask_fc, (__le16 *) &aad[0]);
 905        /* A1 || A2 || A3 */
 906        memcpy(aad + 2, &hdr->addr1, 3 * ETH_ALEN);
 907}
 908
 909
 910static inline void bip_ipn_set64(u8 *d, u64 pn)
 911{
 912        *d++ = pn;
 913        *d++ = pn >> 8;
 914        *d++ = pn >> 16;
 915        *d++ = pn >> 24;
 916        *d++ = pn >> 32;
 917        *d = pn >> 40;
 918}
 919
 920static inline void bip_ipn_swap(u8 *d, const u8 *s)
 921{
 922        *d++ = s[5];
 923        *d++ = s[4];
 924        *d++ = s[3];
 925        *d++ = s[2];
 926        *d++ = s[1];
 927        *d = s[0];
 928}
 929
 930
 931ieee80211_tx_result
 932ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
 933{
 934        struct sk_buff *skb;
 935        struct ieee80211_tx_info *info;
 936        struct ieee80211_key *key = tx->key;
 937        struct ieee80211_mmie *mmie;
 938        u8 aad[20];
 939        u64 pn64;
 940
 941        if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
 942                return TX_DROP;
 943
 944        skb = skb_peek(&tx->skbs);
 945
 946        info = IEEE80211_SKB_CB(skb);
 947
 948        if (info->control.hw_key)
 949                return TX_CONTINUE;
 950
 951        if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
 952                return TX_DROP;
 953
 954        mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie));
 955        mmie->element_id = WLAN_EID_MMIE;
 956        mmie->length = sizeof(*mmie) - 2;
 957        mmie->key_id = cpu_to_le16(key->conf.keyidx);
 958
 959        /* PN = PN + 1 */
 960        pn64 = atomic64_inc_return(&key->conf.tx_pn);
 961
 962        bip_ipn_set64(mmie->sequence_number, pn64);
 963
 964        bip_aad(skb, aad);
 965
 966        /*
 967         * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
 968         */
 969        ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
 970                           skb->data + 24, skb->len - 24, mmie->mic);
 971
 972        return TX_CONTINUE;
 973}
 974
 975ieee80211_tx_result
 976ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx)
 977{
 978        struct sk_buff *skb;
 979        struct ieee80211_tx_info *info;
 980        struct ieee80211_key *key = tx->key;
 981        struct ieee80211_mmie_16 *mmie;
 982        u8 aad[20];
 983        u64 pn64;
 984
 985        if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
 986                return TX_DROP;
 987
 988        skb = skb_peek(&tx->skbs);
 989
 990        info = IEEE80211_SKB_CB(skb);
 991
 992        if (info->control.hw_key)
 993                return TX_CONTINUE;
 994
 995        if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
 996                return TX_DROP;
 997
 998        mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie));
 999        mmie->element_id = WLAN_EID_MMIE;
1000        mmie->length = sizeof(*mmie) - 2;
1001        mmie->key_id = cpu_to_le16(key->conf.keyidx);
1002
1003        /* PN = PN + 1 */
1004        pn64 = atomic64_inc_return(&key->conf.tx_pn);
1005
1006        bip_ipn_set64(mmie->sequence_number, pn64);
1007
1008        bip_aad(skb, aad);
1009
1010        /* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128)
1011         */
1012        ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1013                               skb->data + 24, skb->len - 24, mmie->mic);
1014
1015        return TX_CONTINUE;
1016}
1017
1018ieee80211_rx_result
1019ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
1020{
1021        struct sk_buff *skb = rx->skb;
1022        struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1023        struct ieee80211_key *key = rx->key;
1024        struct ieee80211_mmie *mmie;
1025        u8 aad[20], mic[8], ipn[6];
1026        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1027
1028        if (!ieee80211_is_mgmt(hdr->frame_control))
1029                return RX_CONTINUE;
1030
1031        /* management frames are already linear */
1032
1033        if (skb->len < 24 + sizeof(*mmie))
1034                return RX_DROP_UNUSABLE;
1035
1036        mmie = (struct ieee80211_mmie *)
1037                (skb->data + skb->len - sizeof(*mmie));
1038        if (mmie->element_id != WLAN_EID_MMIE ||
1039            mmie->length != sizeof(*mmie) - 2)
1040                return RX_DROP_UNUSABLE; /* Invalid MMIE */
1041
1042        bip_ipn_swap(ipn, mmie->sequence_number);
1043
1044        if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1045                key->u.aes_cmac.replays++;
1046                return RX_DROP_UNUSABLE;
1047        }
1048
1049        if (!(status->flag & RX_FLAG_DECRYPTED)) {
1050                /* hardware didn't decrypt/verify MIC */
1051                bip_aad(skb, aad);
1052                ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
1053                                   skb->data + 24, skb->len - 24, mic);
1054                if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1055                        key->u.aes_cmac.icverrors++;
1056                        return RX_DROP_UNUSABLE;
1057                }
1058        }
1059
1060        memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1061
1062        /* Remove MMIE */
1063        skb_trim(skb, skb->len - sizeof(*mmie));
1064
1065        return RX_CONTINUE;
1066}
1067
1068ieee80211_rx_result
1069ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx)
1070{
1071        struct sk_buff *skb = rx->skb;
1072        struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1073        struct ieee80211_key *key = rx->key;
1074        struct ieee80211_mmie_16 *mmie;
1075        u8 aad[20], mic[16], ipn[6];
1076        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1077
1078        if (!ieee80211_is_mgmt(hdr->frame_control))
1079                return RX_CONTINUE;
1080
1081        /* management frames are already linear */
1082
1083        if (skb->len < 24 + sizeof(*mmie))
1084                return RX_DROP_UNUSABLE;
1085
1086        mmie = (struct ieee80211_mmie_16 *)
1087                (skb->data + skb->len - sizeof(*mmie));
1088        if (mmie->element_id != WLAN_EID_MMIE ||
1089            mmie->length != sizeof(*mmie) - 2)
1090                return RX_DROP_UNUSABLE; /* Invalid MMIE */
1091
1092        bip_ipn_swap(ipn, mmie->sequence_number);
1093
1094        if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1095                key->u.aes_cmac.replays++;
1096                return RX_DROP_UNUSABLE;
1097        }
1098
1099        if (!(status->flag & RX_FLAG_DECRYPTED)) {
1100                /* hardware didn't decrypt/verify MIC */
1101                bip_aad(skb, aad);
1102                ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1103                                       skb->data + 24, skb->len - 24, mic);
1104                if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1105                        key->u.aes_cmac.icverrors++;
1106                        return RX_DROP_UNUSABLE;
1107                }
1108        }
1109
1110        memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1111
1112        /* Remove MMIE */
1113        skb_trim(skb, skb->len - sizeof(*mmie));
1114
1115        return RX_CONTINUE;
1116}
1117
1118ieee80211_tx_result
1119ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx)
1120{
1121        struct sk_buff *skb;
1122        struct ieee80211_tx_info *info;
1123        struct ieee80211_key *key = tx->key;
1124        struct ieee80211_mmie_16 *mmie;
1125        struct ieee80211_hdr *hdr;
1126        u8 aad[20];
1127        u64 pn64;
1128        u8 nonce[12];
1129
1130        if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
1131                return TX_DROP;
1132
1133        skb = skb_peek(&tx->skbs);
1134
1135        info = IEEE80211_SKB_CB(skb);
1136
1137        if (info->control.hw_key)
1138                return TX_CONTINUE;
1139
1140        if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
1141                return TX_DROP;
1142
1143        mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie));
1144        mmie->element_id = WLAN_EID_MMIE;
1145        mmie->length = sizeof(*mmie) - 2;
1146        mmie->key_id = cpu_to_le16(key->conf.keyidx);
1147
1148        /* PN = PN + 1 */
1149        pn64 = atomic64_inc_return(&key->conf.tx_pn);
1150
1151        bip_ipn_set64(mmie->sequence_number, pn64);
1152
1153        bip_aad(skb, aad);
1154
1155        hdr = (struct ieee80211_hdr *)skb->data;
1156        memcpy(nonce, hdr->addr2, ETH_ALEN);
1157        bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number);
1158
1159        /* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */
1160        if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1161                               skb->data + 24, skb->len - 24, mmie->mic) < 0)
1162                return TX_DROP;
1163
1164        return TX_CONTINUE;
1165}
1166
1167ieee80211_rx_result
1168ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx)
1169{
1170        struct sk_buff *skb = rx->skb;
1171        struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1172        struct ieee80211_key *key = rx->key;
1173        struct ieee80211_mmie_16 *mmie;
1174        u8 aad[20], mic[16], ipn[6], nonce[12];
1175        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1176
1177        if (!ieee80211_is_mgmt(hdr->frame_control))
1178                return RX_CONTINUE;
1179
1180        /* management frames are already linear */
1181
1182        if (skb->len < 24 + sizeof(*mmie))
1183                return RX_DROP_UNUSABLE;
1184
1185        mmie = (struct ieee80211_mmie_16 *)
1186                (skb->data + skb->len - sizeof(*mmie));
1187        if (mmie->element_id != WLAN_EID_MMIE ||
1188            mmie->length != sizeof(*mmie) - 2)
1189                return RX_DROP_UNUSABLE; /* Invalid MMIE */
1190
1191        bip_ipn_swap(ipn, mmie->sequence_number);
1192
1193        if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) {
1194                key->u.aes_gmac.replays++;
1195                return RX_DROP_UNUSABLE;
1196        }
1197
1198        if (!(status->flag & RX_FLAG_DECRYPTED)) {
1199                /* hardware didn't decrypt/verify MIC */
1200                bip_aad(skb, aad);
1201
1202                memcpy(nonce, hdr->addr2, ETH_ALEN);
1203                memcpy(nonce + ETH_ALEN, ipn, 6);
1204
1205                if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1206                                       skb->data + 24, skb->len - 24,
1207                                       mic) < 0 ||
1208                    memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1209                        key->u.aes_gmac.icverrors++;
1210                        return RX_DROP_UNUSABLE;
1211                }
1212        }
1213
1214        memcpy(key->u.aes_gmac.rx_pn, ipn, 6);
1215
1216        /* Remove MMIE */
1217        skb_trim(skb, skb->len - sizeof(*mmie));
1218
1219        return RX_CONTINUE;
1220}
1221
1222ieee80211_tx_result
1223ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx)
1224{
1225        struct sk_buff *skb;
1226        struct ieee80211_tx_info *info = NULL;
1227        ieee80211_tx_result res;
1228
1229        skb_queue_walk(&tx->skbs, skb) {
1230                info  = IEEE80211_SKB_CB(skb);
1231
1232                /* handle hw-only algorithm */
1233                if (!info->control.hw_key)
1234                        return TX_DROP;
1235
1236                if (tx->key->flags & KEY_FLAG_CIPHER_SCHEME) {
1237                        res = ieee80211_crypto_cs_encrypt(tx, skb);
1238                        if (res != TX_CONTINUE)
1239                                return res;
1240                }
1241        }
1242
1243        ieee80211_tx_set_protected(tx);
1244
1245        return TX_CONTINUE;
1246}
1247
1248ieee80211_rx_result
1249ieee80211_crypto_hw_decrypt(struct ieee80211_rx_data *rx)
1250{
1251        if (rx->sta && rx->sta->cipher_scheme)
1252                return ieee80211_crypto_cs_decrypt(rx);
1253
1254        return RX_DROP_UNUSABLE;
1255}
1256