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#include <crypto/algapi.h>
  21
  22#include "ieee80211_i.h"
  23#include "michael.h"
  24#include "tkip.h"
  25#include "aes_ccm.h"
  26#include "aes_cmac.h"
  27#include "aes_gmac.h"
  28#include "aes_gcm.h"
  29#include "wpa.h"
  30
  31ieee80211_tx_result
  32ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
  33{
  34        u8 *data, *key, *mic;
  35        size_t data_len;
  36        unsigned int hdrlen;
  37        struct ieee80211_hdr *hdr;
  38        struct sk_buff *skb = tx->skb;
  39        struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  40        int tail;
  41
  42        hdr = (struct ieee80211_hdr *)skb->data;
  43        if (!tx->key || tx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
  44            skb->len < 24 || !ieee80211_is_data_present(hdr->frame_control))
  45                return TX_CONTINUE;
  46
  47        hdrlen = ieee80211_hdrlen(hdr->frame_control);
  48        if (skb->len < hdrlen)
  49                return TX_DROP;
  50
  51        data = skb->data + hdrlen;
  52        data_len = skb->len - hdrlen;
  53
  54        if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) {
  55                /* Need to use software crypto for the test */
  56                info->control.hw_key = NULL;
  57        }
  58
  59        if (info->control.hw_key &&
  60            (info->flags & IEEE80211_TX_CTL_DONTFRAG ||
  61             ieee80211_hw_check(&tx->local->hw, SUPPORTS_TX_FRAG)) &&
  62            !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) {
  63                /* hwaccel - with no need for SW-generated MMIC */
  64                return TX_CONTINUE;
  65        }
  66
  67        tail = MICHAEL_MIC_LEN;
  68        if (!info->control.hw_key)
  69                tail += IEEE80211_TKIP_ICV_LEN;
  70
  71        if (WARN(skb_tailroom(skb) < tail ||
  72                 skb_headroom(skb) < IEEE80211_TKIP_IV_LEN,
  73                 "mmic: not enough head/tail (%d/%d,%d/%d)\n",
  74                 skb_headroom(skb), IEEE80211_TKIP_IV_LEN,
  75                 skb_tailroom(skb), tail))
  76                return TX_DROP;
  77
  78        key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY];
  79        mic = skb_put(skb, MICHAEL_MIC_LEN);
  80        michael_mic(key, hdr, data, data_len, mic);
  81        if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE))
  82                mic[0]++;
  83
  84        return TX_CONTINUE;
  85}
  86
  87
  88ieee80211_rx_result
  89ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
  90{
  91        u8 *data, *key = NULL;
  92        size_t data_len;
  93        unsigned int hdrlen;
  94        u8 mic[MICHAEL_MIC_LEN];
  95        struct sk_buff *skb = rx->skb;
  96        struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  97        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  98
  99        /*
 100         * it makes no sense to check for MIC errors on anything other
 101         * than data frames.
 102         */
 103        if (!ieee80211_is_data_present(hdr->frame_control))
 104                return RX_CONTINUE;
 105
 106        /*
 107         * No way to verify the MIC if the hardware stripped it or
 108         * the IV with the key index. In this case we have solely rely
 109         * on the driver to set RX_FLAG_MMIC_ERROR in the event of a
 110         * MIC failure report.
 111         */
 112        if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) {
 113                if (status->flag & RX_FLAG_MMIC_ERROR)
 114                        goto mic_fail_no_key;
 115
 116                if (!(status->flag & RX_FLAG_IV_STRIPPED) && rx->key &&
 117                    rx->key->conf.cipher == WLAN_CIPHER_SUITE_TKIP)
 118                        goto update_iv;
 119
 120                return RX_CONTINUE;
 121        }
 122
 123        /*
 124         * Some hardware seems to generate Michael MIC failure reports; even
 125         * though, the frame was not encrypted with TKIP and therefore has no
 126         * MIC. Ignore the flag them to avoid triggering countermeasures.
 127         */
 128        if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
 129            !(status->flag & RX_FLAG_DECRYPTED))
 130                return RX_CONTINUE;
 131
 132        if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) {
 133                /*
 134                 * APs with pairwise keys should never receive Michael MIC
 135                 * errors for non-zero keyidx because these are reserved for
 136                 * group keys and only the AP is sending real multicast
 137                 * frames in the BSS.
 138                 */
 139                return RX_DROP_UNUSABLE;
 140        }
 141
 142        if (status->flag & RX_FLAG_MMIC_ERROR)
 143                goto mic_fail;
 144
 145        hdrlen = ieee80211_hdrlen(hdr->frame_control);
 146        if (skb->len < hdrlen + MICHAEL_MIC_LEN)
 147                return RX_DROP_UNUSABLE;
 148
 149        if (skb_linearize(rx->skb))
 150                return RX_DROP_UNUSABLE;
 151        hdr = (void *)skb->data;
 152
 153        data = skb->data + hdrlen;
 154        data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;
 155        key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY];
 156        michael_mic(key, hdr, data, data_len, mic);
 157        if (crypto_memneq(mic, data + data_len, MICHAEL_MIC_LEN))
 158                goto mic_fail;
 159
 160        /* remove Michael MIC from payload */
 161        skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
 162
 163update_iv:
 164        /* update IV in key information to be able to detect replays */
 165        rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip_iv32;
 166        rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip_iv16;
 167
 168        return RX_CONTINUE;
 169
 170mic_fail:
 171        rx->key->u.tkip.mic_failures++;
 172
 173mic_fail_no_key:
 174        /*
 175         * In some cases the key can be unset - e.g. a multicast packet, in
 176         * a driver that supports HW encryption. Send up the key idx only if
 177         * the key is set.
 178         */
 179        cfg80211_michael_mic_failure(rx->sdata->dev, hdr->addr2,
 180                                     is_multicast_ether_addr(hdr->addr1) ?
 181                                     NL80211_KEYTYPE_GROUP :
 182                                     NL80211_KEYTYPE_PAIRWISE,
 183                                     rx->key ? rx->key->conf.keyidx : -1,
 184                                     NULL, GFP_ATOMIC);
 185        return RX_DROP_UNUSABLE;
 186}
 187
 188static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
 189{
 190        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 191        struct ieee80211_key *key = tx->key;
 192        struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 193        unsigned int hdrlen;
 194        int len, tail;
 195        u64 pn;
 196        u8 *pos;
 197
 198        if (info->control.hw_key &&
 199            !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 200            !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
 201                /* hwaccel - with no need for software-generated IV */
 202                return 0;
 203        }
 204
 205        hdrlen = ieee80211_hdrlen(hdr->frame_control);
 206        len = skb->len - hdrlen;
 207
 208        if (info->control.hw_key)
 209                tail = 0;
 210        else
 211                tail = IEEE80211_TKIP_ICV_LEN;
 212
 213        if (WARN_ON(skb_tailroom(skb) < tail ||
 214                    skb_headroom(skb) < IEEE80211_TKIP_IV_LEN))
 215                return -1;
 216
 217        pos = skb_push(skb, IEEE80211_TKIP_IV_LEN);
 218        memmove(pos, pos + IEEE80211_TKIP_IV_LEN, hdrlen);
 219        pos += hdrlen;
 220
 221        /* the HW only needs room for the IV, but not the actual IV */
 222        if (info->control.hw_key &&
 223            (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 224                return 0;
 225
 226        /* Increase IV for the frame */
 227        pn = atomic64_inc_return(&key->conf.tx_pn);
 228        pos = ieee80211_tkip_add_iv(pos, &key->conf, pn);
 229
 230        /* hwaccel - with software IV */
 231        if (info->control.hw_key)
 232                return 0;
 233
 234        /* Add room for ICV */
 235        skb_put(skb, IEEE80211_TKIP_ICV_LEN);
 236
 237        return ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,
 238                                           key, skb, pos, len);
 239}
 240
 241
 242ieee80211_tx_result
 243ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
 244{
 245        struct sk_buff *skb;
 246
 247        ieee80211_tx_set_protected(tx);
 248
 249        skb_queue_walk(&tx->skbs, skb) {
 250                if (tkip_encrypt_skb(tx, skb) < 0)
 251                        return TX_DROP;
 252        }
 253
 254        return TX_CONTINUE;
 255}
 256
 257
 258ieee80211_rx_result
 259ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
 260{
 261        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 262        int hdrlen, res, hwaccel = 0;
 263        struct ieee80211_key *key = rx->key;
 264        struct sk_buff *skb = rx->skb;
 265        struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 266
 267        hdrlen = ieee80211_hdrlen(hdr->frame_control);
 268
 269        if (!ieee80211_is_data(hdr->frame_control))
 270                return RX_CONTINUE;
 271
 272        if (!rx->sta || skb->len - hdrlen < 12)
 273                return RX_DROP_UNUSABLE;
 274
 275        /* it may be possible to optimize this a bit more */
 276        if (skb_linearize(rx->skb))
 277                return RX_DROP_UNUSABLE;
 278        hdr = (void *)skb->data;
 279
 280        /*
 281         * Let TKIP code verify IV, but skip decryption.
 282         * In the case where hardware checks the IV as well,
 283         * we don't even get here, see ieee80211_rx_h_decrypt()
 284         */
 285        if (status->flag & RX_FLAG_DECRYPTED)
 286                hwaccel = 1;
 287
 288        res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm,
 289                                          key, skb->data + hdrlen,
 290                                          skb->len - hdrlen, rx->sta->sta.addr,
 291                                          hdr->addr1, hwaccel, rx->security_idx,
 292                                          &rx->tkip_iv32,
 293                                          &rx->tkip_iv16);
 294        if (res != TKIP_DECRYPT_OK)
 295                return RX_DROP_UNUSABLE;
 296
 297        /* Trim ICV */
 298        if (!(status->flag & RX_FLAG_ICV_STRIPPED))
 299                skb_trim(skb, skb->len - IEEE80211_TKIP_ICV_LEN);
 300
 301        /* Remove IV */
 302        memmove(skb->data + IEEE80211_TKIP_IV_LEN, skb->data, hdrlen);
 303        skb_pull(skb, IEEE80211_TKIP_IV_LEN);
 304
 305        return RX_CONTINUE;
 306}
 307
 308
 309static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad)
 310{
 311        __le16 mask_fc;
 312        int a4_included, mgmt;
 313        u8 qos_tid;
 314        u16 len_a;
 315        unsigned int hdrlen;
 316        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 317
 318        /*
 319         * Mask FC: zero subtype b4 b5 b6 (if not mgmt)
 320         * Retry, PwrMgt, MoreData; set Protected
 321         */
 322        mgmt = ieee80211_is_mgmt(hdr->frame_control);
 323        mask_fc = hdr->frame_control;
 324        mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
 325                                IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
 326        if (!mgmt)
 327                mask_fc &= ~cpu_to_le16(0x0070);
 328        mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
 329
 330        hdrlen = ieee80211_hdrlen(hdr->frame_control);
 331        len_a = hdrlen - 2;
 332        a4_included = ieee80211_has_a4(hdr->frame_control);
 333
 334        if (ieee80211_is_data_qos(hdr->frame_control))
 335                qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
 336        else
 337                qos_tid = 0;
 338
 339        /* In CCM, the initial vectors (IV) used for CTR mode encryption and CBC
 340         * mode authentication are not allowed to collide, yet both are derived
 341         * from this vector b_0. We only set L := 1 here to indicate that the
 342         * data size can be represented in (L+1) bytes. The CCM layer will take
 343         * care of storing the data length in the top (L+1) bytes and setting
 344         * and clearing the other bits as is required to derive the two IVs.
 345         */
 346        b_0[0] = 0x1;
 347
 348        /* Nonce: Nonce Flags | A2 | PN
 349         * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7)
 350         */
 351        b_0[1] = qos_tid | (mgmt << 4);
 352        memcpy(&b_0[2], hdr->addr2, ETH_ALEN);
 353        memcpy(&b_0[8], pn, IEEE80211_CCMP_PN_LEN);
 354
 355        /* AAD (extra authenticate-only data) / masked 802.11 header
 356         * FC | A1 | A2 | A3 | SC | [A4] | [QC] */
 357        put_unaligned_be16(len_a, &aad[0]);
 358        put_unaligned(mask_fc, (__le16 *)&aad[2]);
 359        memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
 360
 361        /* Mask Seq#, leave Frag# */
 362        aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;
 363        aad[23] = 0;
 364
 365        if (a4_included) {
 366                memcpy(&aad[24], hdr->addr4, ETH_ALEN);
 367                aad[30] = qos_tid;
 368                aad[31] = 0;
 369        } else {
 370                memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
 371                aad[24] = qos_tid;
 372        }
 373}
 374
 375
 376static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)
 377{
 378        hdr[0] = pn[5];
 379        hdr[1] = pn[4];
 380        hdr[2] = 0;
 381        hdr[3] = 0x20 | (key_id << 6);
 382        hdr[4] = pn[3];
 383        hdr[5] = pn[2];
 384        hdr[6] = pn[1];
 385        hdr[7] = pn[0];
 386}
 387
 388
 389static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr)
 390{
 391        pn[0] = hdr[7];
 392        pn[1] = hdr[6];
 393        pn[2] = hdr[5];
 394        pn[3] = hdr[4];
 395        pn[4] = hdr[1];
 396        pn[5] = hdr[0];
 397}
 398
 399
 400static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb,
 401                            unsigned int mic_len)
 402{
 403        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 404        struct ieee80211_key *key = tx->key;
 405        struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 406        int hdrlen, len, tail;
 407        u8 *pos;
 408        u8 pn[6];
 409        u64 pn64;
 410        u8 aad[CCM_AAD_LEN];
 411        u8 b_0[AES_BLOCK_SIZE];
 412
 413        if (info->control.hw_key &&
 414            !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 415            !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 416            !((info->control.hw_key->flags &
 417               IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
 418              ieee80211_is_mgmt(hdr->frame_control))) {
 419                /*
 420                 * hwaccel has no need for preallocated room for CCMP
 421                 * header or MIC fields
 422                 */
 423                return 0;
 424        }
 425
 426        hdrlen = ieee80211_hdrlen(hdr->frame_control);
 427        len = skb->len - hdrlen;
 428
 429        if (info->control.hw_key)
 430                tail = 0;
 431        else
 432                tail = mic_len;
 433
 434        if (WARN_ON(skb_tailroom(skb) < tail ||
 435                    skb_headroom(skb) < IEEE80211_CCMP_HDR_LEN))
 436                return -1;
 437
 438        pos = skb_push(skb, IEEE80211_CCMP_HDR_LEN);
 439        memmove(pos, pos + IEEE80211_CCMP_HDR_LEN, hdrlen);
 440
 441        /* the HW only needs room for the IV, but not the actual IV */
 442        if (info->control.hw_key &&
 443            (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 444                return 0;
 445
 446        hdr = (struct ieee80211_hdr *) pos;
 447        pos += hdrlen;
 448
 449        pn64 = atomic64_inc_return(&key->conf.tx_pn);
 450
 451        pn[5] = pn64;
 452        pn[4] = pn64 >> 8;
 453        pn[3] = pn64 >> 16;
 454        pn[2] = pn64 >> 24;
 455        pn[1] = pn64 >> 32;
 456        pn[0] = pn64 >> 40;
 457
 458        ccmp_pn2hdr(pos, pn, key->conf.keyidx);
 459
 460        /* hwaccel - with software CCMP header */
 461        if (info->control.hw_key)
 462                return 0;
 463
 464        pos += IEEE80211_CCMP_HDR_LEN;
 465        ccmp_special_blocks(skb, pn, b_0, aad);
 466        return ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, b_0, aad, pos, len,
 467                                         skb_put(skb, mic_len), mic_len);
 468}
 469
 470
 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[GCM_AAD_LEN];
 643        u8 j_0[AES_BLOCK_SIZE];
 644
 645        if (info->control.hw_key &&
 646            !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 647            !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 648            !((info->control.hw_key->flags &
 649               IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
 650              ieee80211_is_mgmt(hdr->frame_control))) {
 651                /* hwaccel has no need for preallocated room for GCMP
 652                 * header or MIC fields
 653                 */
 654                return 0;
 655        }
 656
 657        hdrlen = ieee80211_hdrlen(hdr->frame_control);
 658        len = skb->len - hdrlen;
 659
 660        if (info->control.hw_key)
 661                tail = 0;
 662        else
 663                tail = IEEE80211_GCMP_MIC_LEN;
 664
 665        if (WARN_ON(skb_tailroom(skb) < tail ||
 666                    skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN))
 667                return -1;
 668
 669        pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN);
 670        memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen);
 671        skb_set_network_header(skb, skb_network_offset(skb) +
 672                                    IEEE80211_GCMP_HDR_LEN);
 673
 674        /* the HW only needs room for the IV, but not the actual IV */
 675        if (info->control.hw_key &&
 676            (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 677                return 0;
 678
 679        hdr = (struct ieee80211_hdr *)pos;
 680        pos += hdrlen;
 681
 682        pn64 = atomic64_inc_return(&key->conf.tx_pn);
 683
 684        pn[5] = pn64;
 685        pn[4] = pn64 >> 8;
 686        pn[3] = pn64 >> 16;
 687        pn[2] = pn64 >> 24;
 688        pn[1] = pn64 >> 32;
 689        pn[0] = pn64 >> 40;
 690
 691        gcmp_pn2hdr(pos, pn, key->conf.keyidx);
 692
 693        /* hwaccel - with software GCMP header */
 694        if (info->control.hw_key)
 695                return 0;
 696
 697        pos += IEEE80211_GCMP_HDR_LEN;
 698        gcmp_special_blocks(skb, pn, j_0, aad);
 699        return ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len,
 700                                         skb_put(skb, IEEE80211_GCMP_MIC_LEN));
 701}
 702
 703ieee80211_tx_result
 704ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx)
 705{
 706        struct sk_buff *skb;
 707
 708        ieee80211_tx_set_protected(tx);
 709
 710        skb_queue_walk(&tx->skbs, skb) {
 711                if (gcmp_encrypt_skb(tx, skb) < 0)
 712                        return TX_DROP;
 713        }
 714
 715        return TX_CONTINUE;
 716}
 717
 718ieee80211_rx_result
 719ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
 720{
 721        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 722        int hdrlen;
 723        struct ieee80211_key *key = rx->key;
 724        struct sk_buff *skb = rx->skb;
 725        struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 726        u8 pn[IEEE80211_GCMP_PN_LEN];
 727        int data_len, queue, mic_len = IEEE80211_GCMP_MIC_LEN;
 728
 729        hdrlen = ieee80211_hdrlen(hdr->frame_control);
 730
 731        if (!ieee80211_is_data(hdr->frame_control) &&
 732            !ieee80211_is_robust_mgmt_frame(skb))
 733                return RX_CONTINUE;
 734
 735        if (status->flag & RX_FLAG_DECRYPTED) {
 736                if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN))
 737                        return RX_DROP_UNUSABLE;
 738                if (status->flag & RX_FLAG_MIC_STRIPPED)
 739                        mic_len = 0;
 740        } else {
 741                if (skb_linearize(rx->skb))
 742                        return RX_DROP_UNUSABLE;
 743        }
 744
 745        data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN - mic_len;
 746        if (!rx->sta || data_len < 0)
 747                return RX_DROP_UNUSABLE;
 748
 749        if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
 750                int res;
 751
 752                gcmp_hdr2pn(pn, skb->data + hdrlen);
 753
 754                queue = rx->security_idx;
 755
 756                res = memcmp(pn, key->u.gcmp.rx_pn[queue],
 757                             IEEE80211_GCMP_PN_LEN);
 758                if (res < 0 ||
 759                    (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
 760                        key->u.gcmp.replays++;
 761                        return RX_DROP_UNUSABLE;
 762                }
 763
 764                if (!(status->flag & RX_FLAG_DECRYPTED)) {
 765                        u8 aad[2 * AES_BLOCK_SIZE];
 766                        u8 j_0[AES_BLOCK_SIZE];
 767                        /* hardware didn't decrypt/verify MIC */
 768                        gcmp_special_blocks(skb, pn, j_0, aad);
 769
 770                        if (ieee80211_aes_gcm_decrypt(
 771                                    key->u.gcmp.tfm, j_0, aad,
 772                                    skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN,
 773                                    data_len,
 774                                    skb->data + skb->len -
 775                                    IEEE80211_GCMP_MIC_LEN))
 776                                return RX_DROP_UNUSABLE;
 777                }
 778
 779                memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN);
 780        }
 781
 782        /* Remove GCMP header and MIC */
 783        if (pskb_trim(skb, skb->len - mic_len))
 784                return RX_DROP_UNUSABLE;
 785        memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen);
 786        skb_pull(skb, IEEE80211_GCMP_HDR_LEN);
 787
 788        return RX_CONTINUE;
 789}
 790
 791static ieee80211_tx_result
 792ieee80211_crypto_cs_encrypt(struct ieee80211_tx_data *tx,
 793                            struct sk_buff *skb)
 794{
 795        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 796        struct ieee80211_key *key = tx->key;
 797        struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 798        int hdrlen;
 799        u8 *pos, iv_len = key->conf.iv_len;
 800
 801        if (info->control.hw_key &&
 802            !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
 803                /* hwaccel has no need for preallocated head room */
 804                return TX_CONTINUE;
 805        }
 806
 807        if (unlikely(skb_headroom(skb) < iv_len &&
 808                     pskb_expand_head(skb, iv_len, 0, GFP_ATOMIC)))
 809                return TX_DROP;
 810
 811        hdrlen = ieee80211_hdrlen(hdr->frame_control);
 812
 813        pos = skb_push(skb, iv_len);
 814        memmove(pos, pos + iv_len, hdrlen);
 815
 816        return TX_CONTINUE;
 817}
 818
 819static inline int ieee80211_crypto_cs_pn_compare(u8 *pn1, u8 *pn2, int len)
 820{
 821        int i;
 822
 823        /* pn is little endian */
 824        for (i = len - 1; i >= 0; i--) {
 825                if (pn1[i] < pn2[i])
 826                        return -1;
 827                else if (pn1[i] > pn2[i])
 828                        return 1;
 829        }
 830
 831        return 0;
 832}
 833
 834static ieee80211_rx_result
 835ieee80211_crypto_cs_decrypt(struct ieee80211_rx_data *rx)
 836{
 837        struct ieee80211_key *key = rx->key;
 838        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 839        const struct ieee80211_cipher_scheme *cs = NULL;
 840        int hdrlen = ieee80211_hdrlen(hdr->frame_control);
 841        struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 842        int data_len;
 843        u8 *rx_pn;
 844        u8 *skb_pn;
 845        u8 qos_tid;
 846
 847        if (!rx->sta || !rx->sta->cipher_scheme ||
 848            !(status->flag & RX_FLAG_DECRYPTED))
 849                return RX_DROP_UNUSABLE;
 850
 851        if (!ieee80211_is_data(hdr->frame_control))
 852                return RX_CONTINUE;
 853
 854        cs = rx->sta->cipher_scheme;
 855
 856        data_len = rx->skb->len - hdrlen - cs->hdr_len;
 857
 858        if (data_len < 0)
 859                return RX_DROP_UNUSABLE;
 860
 861        if (ieee80211_is_data_qos(hdr->frame_control))
 862                qos_tid = *ieee80211_get_qos_ctl(hdr) &
 863                                IEEE80211_QOS_CTL_TID_MASK;
 864        else
 865                qos_tid = 0;
 866
 867        if (skb_linearize(rx->skb))
 868                return RX_DROP_UNUSABLE;
 869
 870        hdr = (struct ieee80211_hdr *)rx->skb->data;
 871
 872        rx_pn = key->u.gen.rx_pn[qos_tid];
 873        skb_pn = rx->skb->data + hdrlen + cs->pn_off;
 874
 875        if (ieee80211_crypto_cs_pn_compare(skb_pn, rx_pn, cs->pn_len) <= 0)
 876                return RX_DROP_UNUSABLE;
 877
 878        memcpy(rx_pn, skb_pn, cs->pn_len);
 879
 880        /* remove security header and MIC */
 881        if (pskb_trim(rx->skb, rx->skb->len - cs->mic_len))
 882                return RX_DROP_UNUSABLE;
 883
 884        memmove(rx->skb->data + cs->hdr_len, rx->skb->data, hdrlen);
 885        skb_pull(rx->skb, cs->hdr_len);
 886
 887        return RX_CONTINUE;
 888}
 889
 890static void bip_aad(struct sk_buff *skb, u8 *aad)
 891{
 892        __le16 mask_fc;
 893        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 894
 895        /* BIP AAD: FC(masked) || A1 || A2 || A3 */
 896
 897        /* FC type/subtype */
 898        /* Mask FC Retry, PwrMgt, MoreData flags to zero */
 899        mask_fc = hdr->frame_control;
 900        mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM |
 901                                IEEE80211_FCTL_MOREDATA);
 902        put_unaligned(mask_fc, (__le16 *) &aad[0]);
 903        /* A1 || A2 || A3 */
 904        memcpy(aad + 2, &hdr->addr1, 3 * ETH_ALEN);
 905}
 906
 907
 908static inline void bip_ipn_set64(u8 *d, u64 pn)
 909{
 910        *d++ = pn;
 911        *d++ = pn >> 8;
 912        *d++ = pn >> 16;
 913        *d++ = pn >> 24;
 914        *d++ = pn >> 32;
 915        *d = pn >> 40;
 916}
 917
 918static inline void bip_ipn_swap(u8 *d, const u8 *s)
 919{
 920        *d++ = s[5];
 921        *d++ = s[4];
 922        *d++ = s[3];
 923        *d++ = s[2];
 924        *d++ = s[1];
 925        *d = s[0];
 926}
 927
 928
 929ieee80211_tx_result
 930ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
 931{
 932        struct sk_buff *skb;
 933        struct ieee80211_tx_info *info;
 934        struct ieee80211_key *key = tx->key;
 935        struct ieee80211_mmie *mmie;
 936        u8 aad[20];
 937        u64 pn64;
 938
 939        if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
 940                return TX_DROP;
 941
 942        skb = skb_peek(&tx->skbs);
 943
 944        info = IEEE80211_SKB_CB(skb);
 945
 946        if (info->control.hw_key)
 947                return TX_CONTINUE;
 948
 949        if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
 950                return TX_DROP;
 951
 952        mmie = skb_put(skb, sizeof(*mmie));
 953        mmie->element_id = WLAN_EID_MMIE;
 954        mmie->length = sizeof(*mmie) - 2;
 955        mmie->key_id = cpu_to_le16(key->conf.keyidx);
 956
 957        /* PN = PN + 1 */
 958        pn64 = atomic64_inc_return(&key->conf.tx_pn);
 959
 960        bip_ipn_set64(mmie->sequence_number, pn64);
 961
 962        bip_aad(skb, aad);
 963
 964        /*
 965         * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
 966         */
 967        ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
 968                           skb->data + 24, skb->len - 24, mmie->mic);
 969
 970        return TX_CONTINUE;
 971}
 972
 973ieee80211_tx_result
 974ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx)
 975{
 976        struct sk_buff *skb;
 977        struct ieee80211_tx_info *info;
 978        struct ieee80211_key *key = tx->key;
 979        struct ieee80211_mmie_16 *mmie;
 980        u8 aad[20];
 981        u64 pn64;
 982
 983        if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
 984                return TX_DROP;
 985
 986        skb = skb_peek(&tx->skbs);
 987
 988        info = IEEE80211_SKB_CB(skb);
 989
 990        if (info->control.hw_key)
 991                return TX_CONTINUE;
 992
 993        if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
 994                return TX_DROP;
 995
 996        mmie = skb_put(skb, sizeof(*mmie));
 997        mmie->element_id = WLAN_EID_MMIE;
 998        mmie->length = sizeof(*mmie) - 2;
 999        mmie->key_id = cpu_to_le16(key->conf.keyidx);
1000
1001        /* PN = PN + 1 */
1002        pn64 = atomic64_inc_return(&key->conf.tx_pn);
1003
1004        bip_ipn_set64(mmie->sequence_number, pn64);
1005
1006        bip_aad(skb, aad);
1007
1008        /* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128)
1009         */
1010        ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1011                               skb->data + 24, skb->len - 24, mmie->mic);
1012
1013        return TX_CONTINUE;
1014}
1015
1016ieee80211_rx_result
1017ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
1018{
1019        struct sk_buff *skb = rx->skb;
1020        struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1021        struct ieee80211_key *key = rx->key;
1022        struct ieee80211_mmie *mmie;
1023        u8 aad[20], mic[8], ipn[6];
1024        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1025
1026        if (!ieee80211_is_mgmt(hdr->frame_control))
1027                return RX_CONTINUE;
1028
1029        /* management frames are already linear */
1030
1031        if (skb->len < 24 + sizeof(*mmie))
1032                return RX_DROP_UNUSABLE;
1033
1034        mmie = (struct ieee80211_mmie *)
1035                (skb->data + skb->len - sizeof(*mmie));
1036        if (mmie->element_id != WLAN_EID_MMIE ||
1037            mmie->length != sizeof(*mmie) - 2)
1038                return RX_DROP_UNUSABLE; /* Invalid MMIE */
1039
1040        bip_ipn_swap(ipn, mmie->sequence_number);
1041
1042        if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1043                key->u.aes_cmac.replays++;
1044                return RX_DROP_UNUSABLE;
1045        }
1046
1047        if (!(status->flag & RX_FLAG_DECRYPTED)) {
1048                /* hardware didn't decrypt/verify MIC */
1049                bip_aad(skb, aad);
1050                ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
1051                                   skb->data + 24, skb->len - 24, mic);
1052                if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
1053                        key->u.aes_cmac.icverrors++;
1054                        return RX_DROP_UNUSABLE;
1055                }
1056        }
1057
1058        memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1059
1060        /* Remove MMIE */
1061        skb_trim(skb, skb->len - sizeof(*mmie));
1062
1063        return RX_CONTINUE;
1064}
1065
1066ieee80211_rx_result
1067ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx)
1068{
1069        struct sk_buff *skb = rx->skb;
1070        struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1071        struct ieee80211_key *key = rx->key;
1072        struct ieee80211_mmie_16 *mmie;
1073        u8 aad[20], mic[16], ipn[6];
1074        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1075
1076        if (!ieee80211_is_mgmt(hdr->frame_control))
1077                return RX_CONTINUE;
1078
1079        /* management frames are already linear */
1080
1081        if (skb->len < 24 + sizeof(*mmie))
1082                return RX_DROP_UNUSABLE;
1083
1084        mmie = (struct ieee80211_mmie_16 *)
1085                (skb->data + skb->len - sizeof(*mmie));
1086        if (mmie->element_id != WLAN_EID_MMIE ||
1087            mmie->length != sizeof(*mmie) - 2)
1088                return RX_DROP_UNUSABLE; /* Invalid MMIE */
1089
1090        bip_ipn_swap(ipn, mmie->sequence_number);
1091
1092        if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1093                key->u.aes_cmac.replays++;
1094                return RX_DROP_UNUSABLE;
1095        }
1096
1097        if (!(status->flag & RX_FLAG_DECRYPTED)) {
1098                /* hardware didn't decrypt/verify MIC */
1099                bip_aad(skb, aad);
1100                ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1101                                       skb->data + 24, skb->len - 24, mic);
1102                if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
1103                        key->u.aes_cmac.icverrors++;
1104                        return RX_DROP_UNUSABLE;
1105                }
1106        }
1107
1108        memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1109
1110        /* Remove MMIE */
1111        skb_trim(skb, skb->len - sizeof(*mmie));
1112
1113        return RX_CONTINUE;
1114}
1115
1116ieee80211_tx_result
1117ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx)
1118{
1119        struct sk_buff *skb;
1120        struct ieee80211_tx_info *info;
1121        struct ieee80211_key *key = tx->key;
1122        struct ieee80211_mmie_16 *mmie;
1123        struct ieee80211_hdr *hdr;
1124        u8 aad[GMAC_AAD_LEN];
1125        u64 pn64;
1126        u8 nonce[GMAC_NONCE_LEN];
1127
1128        if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
1129                return TX_DROP;
1130
1131        skb = skb_peek(&tx->skbs);
1132
1133        info = IEEE80211_SKB_CB(skb);
1134
1135        if (info->control.hw_key)
1136                return TX_CONTINUE;
1137
1138        if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
1139                return TX_DROP;
1140
1141        mmie = skb_put(skb, sizeof(*mmie));
1142        mmie->element_id = WLAN_EID_MMIE;
1143        mmie->length = sizeof(*mmie) - 2;
1144        mmie->key_id = cpu_to_le16(key->conf.keyidx);
1145
1146        /* PN = PN + 1 */
1147        pn64 = atomic64_inc_return(&key->conf.tx_pn);
1148
1149        bip_ipn_set64(mmie->sequence_number, pn64);
1150
1151        bip_aad(skb, aad);
1152
1153        hdr = (struct ieee80211_hdr *)skb->data;
1154        memcpy(nonce, hdr->addr2, ETH_ALEN);
1155        bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number);
1156
1157        /* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */
1158        if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1159                               skb->data + 24, skb->len - 24, mmie->mic) < 0)
1160                return TX_DROP;
1161
1162        return TX_CONTINUE;
1163}
1164
1165ieee80211_rx_result
1166ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx)
1167{
1168        struct sk_buff *skb = rx->skb;
1169        struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1170        struct ieee80211_key *key = rx->key;
1171        struct ieee80211_mmie_16 *mmie;
1172        u8 aad[GMAC_AAD_LEN], mic[GMAC_MIC_LEN], ipn[6], nonce[GMAC_NONCE_LEN];
1173        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1174
1175        if (!ieee80211_is_mgmt(hdr->frame_control))
1176                return RX_CONTINUE;
1177
1178        /* management frames are already linear */
1179
1180        if (skb->len < 24 + sizeof(*mmie))
1181                return RX_DROP_UNUSABLE;
1182
1183        mmie = (struct ieee80211_mmie_16 *)
1184                (skb->data + skb->len - sizeof(*mmie));
1185        if (mmie->element_id != WLAN_EID_MMIE ||
1186            mmie->length != sizeof(*mmie) - 2)
1187                return RX_DROP_UNUSABLE; /* Invalid MMIE */
1188
1189        bip_ipn_swap(ipn, mmie->sequence_number);
1190
1191        if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) {
1192                key->u.aes_gmac.replays++;
1193                return RX_DROP_UNUSABLE;
1194        }
1195
1196        if (!(status->flag & RX_FLAG_DECRYPTED)) {
1197                /* hardware didn't decrypt/verify MIC */
1198                bip_aad(skb, aad);
1199
1200                memcpy(nonce, hdr->addr2, ETH_ALEN);
1201                memcpy(nonce + ETH_ALEN, ipn, 6);
1202
1203                if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1204                                       skb->data + 24, skb->len - 24,
1205                                       mic) < 0 ||
1206                    crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
1207                        key->u.aes_gmac.icverrors++;
1208                        return RX_DROP_UNUSABLE;
1209                }
1210        }
1211
1212        memcpy(key->u.aes_gmac.rx_pn, ipn, 6);
1213
1214        /* Remove MMIE */
1215        skb_trim(skb, skb->len - sizeof(*mmie));
1216
1217        return RX_CONTINUE;
1218}
1219
1220ieee80211_tx_result
1221ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx)
1222{
1223        struct sk_buff *skb;
1224        struct ieee80211_tx_info *info = NULL;
1225        ieee80211_tx_result res;
1226
1227        skb_queue_walk(&tx->skbs, skb) {
1228                info  = IEEE80211_SKB_CB(skb);
1229
1230                /* handle hw-only algorithm */
1231                if (!info->control.hw_key)
1232                        return TX_DROP;
1233
1234                if (tx->key->flags & KEY_FLAG_CIPHER_SCHEME) {
1235                        res = ieee80211_crypto_cs_encrypt(tx, skb);
1236                        if (res != TX_CONTINUE)
1237                                return res;
1238                }
1239        }
1240
1241        ieee80211_tx_set_protected(tx);
1242
1243        return TX_CONTINUE;
1244}
1245
1246ieee80211_rx_result
1247ieee80211_crypto_hw_decrypt(struct ieee80211_rx_data *rx)
1248{
1249        if (rx->sta && rx->sta->cipher_scheme)
1250                return ieee80211_crypto_cs_decrypt(rx);
1251
1252        return RX_DROP_UNUSABLE;
1253}
1254