net/mac80211/rx.c

   1 /*
   2  * Copyright 2002-2005, Instant802 Networks, Inc.
   3  * Copyright 2005-2006, Devicescape Software, Inc.
   4  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   5  * Copyright 2007-2010  Johannes Berg <johannes@sipsolutions.net>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/jiffies.h>
  13 #include <linux/slab.h>
  14 #include <linux/kernel.h>
  15 #include <linux/skbuff.h>
  16 #include <linux/netdevice.h>
  17 #include <linux/etherdevice.h>
  18 #include <linux/rcupdate.h>
  19 #include <net/mac80211.h>
  20 #include <net/ieee80211_radiotap.h>
  21
  22 #include "ieee80211_i.h"
  23 #include "driver-ops.h"
  24 #include "led.h"
  25 #include "mesh.h"
  26 #include "wep.h"
  27 #include "wpa.h"
  28 #include "tkip.h"
  29 #include "wme.h"
  30
  31 /*
  32  * monitor mode reception
  33  *
  34  * This function cleans up the SKB, i.e. it removes all the stuff
  35  * only useful for monitoring.
  36  */
  37 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
  38                                            struct sk_buff *skb)
  39 {
  40         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
  41                 if (likely(skb->len > FCS_LEN))
  42                         __pskb_trim(skb, skb->len - FCS_LEN);
  43                 else {
  44                         /* driver bug */
  45                         WARN_ON(1);
  46                         dev_kfree_skb(skb);
  47                         skb = NULL;
  48                 }
  49         }
  50
  51         return skb;
  52 }
  53
  54 static inline int should_drop_frame(struct sk_buff *skb,
  55                                     int present_fcs_len)
  56 {
  57         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  58         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  59
  60         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
  61                 return 1;
  62         if (unlikely(skb->len < 16 + present_fcs_len))
  63                 return 1;
  64         if (ieee80211_is_ctl(hdr->frame_control) &&
  65             !ieee80211_is_pspoll(hdr->frame_control) &&
  66             !ieee80211_is_back_req(hdr->frame_control))
  67                 return 1;
  68         return 0;
  69 }
  70
  71 static int
  72 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
  73                           struct ieee80211_rx_status *status)
  74 {
  75         int len;
  76
  77         /* always present fields */
  78         len = sizeof(struct ieee80211_radiotap_header) + 9;
  79
  80         if (status->flag & RX_FLAG_TSFT)
  81                 len += 8;
  82         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
  83                 len += 1;
  84
  85         if (len & 1) /* padding for RX_FLAGS if necessary */
  86                 len++;
  87
  88         return len;
  89 }
  90
  91 /*
  92  * ieee80211_add_rx_radiotap_header - add radiotap header
  93  *
  94  * add a radiotap header containing all the fields which the hardware provided.
  95  */
  96 static void
  97 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
  98                                  struct sk_buff *skb,
  99                                  struct ieee80211_rate *rate,
 100                                  int rtap_len)
 101 {
 102         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 103         struct ieee80211_radiotap_header *rthdr;
 104         unsigned char *pos;
 105         u16 rx_flags = 0;
 106
 107         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
 108         memset(rthdr, 0, rtap_len);
 109
 110         /* radiotap header, set always present flags */
 111         rthdr->it_present =
 112                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 113                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
 114                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
 115                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
 116         rthdr->it_len = cpu_to_le16(rtap_len);
 117
 118         pos = (unsigned char *)(rthdr+1);
 119
 120         /* the order of the following fields is important */
 121
 122         /* IEEE80211_RADIOTAP_TSFT */
 123         if (status->flag & RX_FLAG_TSFT) {
 124                 put_unaligned_le64(status->mactime, pos);
 125                 rthdr->it_present |=
 126                         cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
 127                 pos += 8;
 128         }
 129
 130         /* IEEE80211_RADIOTAP_FLAGS */
 131         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 132                 *pos |= IEEE80211_RADIOTAP_F_FCS;
 133         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 134                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
 135         if (status->flag & RX_FLAG_SHORTPRE)
 136                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
 137         pos++;
 138
 139         /* IEEE80211_RADIOTAP_RATE */
 140         if (status->flag & RX_FLAG_HT) {
 141                 /*
 142                  * TODO: add following information into radiotap header once
 143                  * suitable fields are defined for it:
 144                  * - MCS index (status->rate_idx)
 145                  * - HT40 (status->flag & RX_FLAG_40MHZ)
 146                  * - short-GI (status->flag & RX_FLAG_SHORT_GI)
 147                  */
 148                 *pos = 0;
 149         } else {
 150                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
 151                 *pos = rate->bitrate / 5;
 152         }
 153         pos++;
 154
 155         /* IEEE80211_RADIOTAP_CHANNEL */
 156         put_unaligned_le16(status->freq, pos);
 157         pos += 2;
 158         if (status->band == IEEE80211_BAND_5GHZ)
 159                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
 160                                    pos);
 161         else if (status->flag & RX_FLAG_HT)
 162                 put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ,
 163                                    pos);
 164         else if (rate->flags & IEEE80211_RATE_ERP_G)
 165                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
 166                                    pos);
 167         else
 168                 put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
 169                                    pos);
 170         pos += 2;
 171
 172         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
 173         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
 174                 *pos = status->signal;
 175                 rthdr->it_present |=
 176                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
 177                 pos++;
 178         }
 179
 180         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
 181
 182         /* IEEE80211_RADIOTAP_ANTENNA */
 183         *pos = status->antenna;
 184         pos++;
 185
 186         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
 187
 188         /* IEEE80211_RADIOTAP_RX_FLAGS */
 189         /* ensure 2 byte alignment for the 2 byte field as required */
 190         if ((pos - (u8 *)rthdr) & 1)
 191                 pos++;
 192         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
 193                 rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
 194         put_unaligned_le16(rx_flags, pos);
 195         pos += 2;
 196 }
 197
 198 /*
 199  * This function copies a received frame to all monitor interfaces and
 200  * returns a cleaned-up SKB that no longer includes the FCS nor the
 201  * radiotap header the driver might have added.
 202  */
 203 static struct sk_buff *
 204 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
 205                      struct ieee80211_rate *rate)
 206 {
 207         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
 208         struct ieee80211_sub_if_data *sdata;
 209         int needed_headroom = 0;
 210         struct sk_buff *skb, *skb2;
 211         struct net_device *prev_dev = NULL;
 212         int present_fcs_len = 0;
 213
 214         /*
 215          * First, we may need to make a copy of the skb because
 216          *  (1) we need to modify it for radiotap (if not present), and
 217          *  (2) the other RX handlers will modify the skb we got.
 218          *
 219          * We don't need to, of course, if we aren't going to return
 220          * the SKB because it has a bad FCS/PLCP checksum.
 221          */
 222
 223         /* room for the radiotap header based on driver features */
 224         needed_headroom = ieee80211_rx_radiotap_len(local, status);
 225
 226         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 227                 present_fcs_len = FCS_LEN;
 228
 229         /* make sure hdr->frame_control is on the linear part */
 230         if (!pskb_may_pull(origskb, 2)) {
 231                 dev_kfree_skb(origskb);
 232                 return NULL;
 233         }
 234
 235         if (!local->monitors) {
 236                 if (should_drop_frame(origskb, present_fcs_len)) {
 237                         dev_kfree_skb(origskb);
 238                         return NULL;
 239                 }
 240
 241                 return remove_monitor_info(local, origskb);
 242         }
 243
 244         if (should_drop_frame(origskb, present_fcs_len)) {
 245                 /* only need to expand headroom if necessary */
 246                 skb = origskb;
 247                 origskb = NULL;
 248
 249                 /*
 250                  * This shouldn't trigger often because most devices have an
 251                  * RX header they pull before we get here, and that should
 252                  * be big enough for our radiotap information. We should
 253                  * probably export the length to drivers so that we can have
 254                  * them allocate enough headroom to start with.
 255                  */
 256                 if (skb_headroom(skb) < needed_headroom &&
 257                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
 258                         dev_kfree_skb(skb);
 259                         return NULL;
 260                 }
 261         } else {
 262                 /*
 263                  * Need to make a copy and possibly remove radiotap header
 264                  * and FCS from the original.
 265                  */
 266                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
 267
 268                 origskb = remove_monitor_info(local, origskb);
 269
 270                 if (!skb)
 271                         return origskb;
 272         }
 273
 274         /* prepend radiotap information */
 275         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom);
 276
 277         skb_reset_mac_header(skb);
 278         skb->ip_summed = CHECKSUM_UNNECESSARY;
 279         skb->pkt_type = PACKET_OTHERHOST;
 280         skb->protocol = htons(ETH_P_802_2);
 281
 282         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 283                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
 284                         continue;
 285
 286                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
 287                         continue;
 288
 289                 if (!ieee80211_sdata_running(sdata))
 290                         continue;
 291
 292                 if (prev_dev) {
 293                         skb2 = skb_clone(skb, GFP_ATOMIC);
 294                         if (skb2) {
 295                                 skb2->dev = prev_dev;
 296                                 netif_receive_skb(skb2);
 297                         }
 298                 }
 299
 300                 prev_dev = sdata->dev;
 301                 sdata->dev->stats.rx_packets++;
 302                 sdata->dev->stats.rx_bytes += skb->len;
 303         }
 304
 305         if (prev_dev) {
 306                 skb->dev = prev_dev;
 307                 netif_receive_skb(skb);
 308         } else
 309                 dev_kfree_skb(skb);
 310
 311         return origskb;
 312 }
 313
 314
 315 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
 316 {
 317         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 318         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 319         int tid;
 320
 321         /* does the frame have a qos control field? */
 322         if (ieee80211_is_data_qos(hdr->frame_control)) {
 323                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 324                 /* frame has qos control */
 325                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
 326                 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
 327                         status->rx_flags |= IEEE80211_RX_AMSDU;
 328         } else {
 329                 /*
 330                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
 331                  *
 332                  *      Sequence numbers for management frames, QoS data
 333                  *      frames with a broadcast/multicast address in the
 334                  *      Address 1 field, and all non-QoS data frames sent
 335                  *      by QoS STAs are assigned using an additional single
 336                  *      modulo-4096 counter, [...]
 337                  *
 338                  * We also use that counter for non-QoS STAs.
 339                  */
 340                 tid = NUM_RX_DATA_QUEUES - 1;
 341         }
 342
 343         rx->queue = tid;
 344         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 345          * For now, set skb->priority to 0 for other cases. */
 346         rx->skb->priority = (tid > 7) ? 0 : tid;
 347 }
 348
 349 /**
 350  * DOC: Packet alignment
 351  *
 352  * Drivers always need to pass packets that are aligned to two-byte boundaries
 353  * to the stack.
 354  *
 355  * Additionally, should, if possible, align the payload data in a way that
 356  * guarantees that the contained IP header is aligned to a four-byte
 357  * boundary. In the case of regular frames, this simply means aligning the
 358  * payload to a four-byte boundary (because either the IP header is directly
 359  * contained, or IV/RFC1042 headers that have a length divisible by four are
 360  * in front of it).  If the payload data is not properly aligned and the
 361  * architecture doesn't support efficient unaligned operations, mac80211
 362  * will align the data.
 363  *
 364  * With A-MSDU frames, however, the payload data address must yield two modulo
 365  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
 366  * push the IP header further back to a multiple of four again. Thankfully, the
 367  * specs were sane enough this time around to require padding each A-MSDU
 368  * subframe to a length that is a multiple of four.
 369  *
 370  * Padding like Atheros hardware adds which is inbetween the 802.11 header and
 371  * the payload is not supported, the driver is required to move the 802.11
 372  * header to be directly in front of the payload in that case.
 373  */
 374 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
 375 {
 376 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 377         WARN_ONCE((unsigned long)rx->skb->data & 1,
 378                   "unaligned packet at 0x%p\n", rx->skb->data);
 379 #endif
 380 }
 381
 382
 383 /* rx handlers */
 384
 385 static ieee80211_rx_result debug_noinline
 386 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
 387 {
 388         struct ieee80211_local *local = rx->local;
 389         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 390         struct sk_buff *skb = rx->skb;
 391
 392         if (likely(!(status->rx_flags & IEEE80211_RX_IN_SCAN)))
 393                 return RX_CONTINUE;
 394
 395         if (test_bit(SCAN_HW_SCANNING, &local->scanning))
 396                 return ieee80211_scan_rx(rx->sdata, skb);
 397
 398         if (test_bit(SCAN_SW_SCANNING, &local->scanning)) {
 399                 /* drop all the other packets during a software scan anyway */
 400                 if (ieee80211_scan_rx(rx->sdata, skb) != RX_QUEUED)
 401                         dev_kfree_skb(skb);
 402                 return RX_QUEUED;
 403         }
 404
 405         /* scanning finished during invoking of handlers */
 406         I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
 407         return RX_DROP_UNUSABLE;
 408 }
 409
 410
 411 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
 412 {
 413         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 414
 415         if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
 416                 return 0;
 417
 418         return ieee80211_is_robust_mgmt_frame(hdr);
 419 }
 420
 421
 422 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
 423 {
 424         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 425
 426         if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
 427                 return 0;
 428
 429         return ieee80211_is_robust_mgmt_frame(hdr);
 430 }
 431
 432
 433 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
 434 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
 435 {
 436         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
 437         struct ieee80211_mmie *mmie;
 438
 439         if (skb->len < 24 + sizeof(*mmie) ||
 440             !is_multicast_ether_addr(hdr->da))
 441                 return -1;
 442
 443         if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
 444                 return -1; /* not a robust management frame */
 445
 446         mmie = (struct ieee80211_mmie *)
 447                 (skb->data + skb->len - sizeof(*mmie));
 448         if (mmie->element_id != WLAN_EID_MMIE ||
 449             mmie->length != sizeof(*mmie) - 2)
 450                 return -1;
 451
 452         return le16_to_cpu(mmie->key_id);
 453 }
 454
 455
 456 static ieee80211_rx_result
 457 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
 458 {
 459         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 460         unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
 461         char *dev_addr = rx->sdata->vif.addr;
 462
 463         if (ieee80211_is_data(hdr->frame_control)) {
 464                 if (is_multicast_ether_addr(hdr->addr1)) {
 465                         if (ieee80211_has_tods(hdr->frame_control) ||
 466                                 !ieee80211_has_fromds(hdr->frame_control))
 467                                 return RX_DROP_MONITOR;
 468                         if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0)
 469                                 return RX_DROP_MONITOR;
 470                 } else {
 471                         if (!ieee80211_has_a4(hdr->frame_control))
 472                                 return RX_DROP_MONITOR;
 473                         if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0)
 474                                 return RX_DROP_MONITOR;
 475                 }
 476         }
 477
 478         /* If there is not an established peer link and this is not a peer link
 479          * establisment frame, beacon or probe, drop the frame.
 480          */
 481
 482         if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
 483                 struct ieee80211_mgmt *mgmt;
 484
 485                 if (!ieee80211_is_mgmt(hdr->frame_control))
 486                         return RX_DROP_MONITOR;
 487
 488                 if (ieee80211_is_action(hdr->frame_control)) {
 489                         mgmt = (struct ieee80211_mgmt *)hdr;
 490                         if (mgmt->u.action.category != WLAN_CATEGORY_MESH_PLINK)
 491                                 return RX_DROP_MONITOR;
 492                         return RX_CONTINUE;
 493                 }
 494
 495                 if (ieee80211_is_probe_req(hdr->frame_control) ||
 496                     ieee80211_is_probe_resp(hdr->frame_control) ||
 497                     ieee80211_is_beacon(hdr->frame_control))
 498                         return RX_CONTINUE;
 499
 500                 return RX_DROP_MONITOR;
 501
 502         }
 503
 504 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
 505
 506         if (ieee80211_is_data(hdr->frame_control) &&
 507             is_multicast_ether_addr(hdr->addr1) &&
 508             mesh_rmc_check(hdr->addr3, msh_h_get(hdr, hdrlen), rx->sdata))
 509                 return RX_DROP_MONITOR;
 510 #undef msh_h_get
 511
 512         return RX_CONTINUE;
 513 }
 514
 515 #define SEQ_MODULO 0x1000
 516 #define SEQ_MASK   0xfff
 517
 518 static inline int seq_less(u16 sq1, u16 sq2)
 519 {
 520         return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
 521 }
 522
 523 static inline u16 seq_inc(u16 sq)
 524 {
 525         return (sq + 1) & SEQ_MASK;
 526 }
 527
 528 static inline u16 seq_sub(u16 sq1, u16 sq2)
 529 {
 530         return (sq1 - sq2) & SEQ_MASK;
 531 }
 532
 533
 534 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
 535                                             struct tid_ampdu_rx *tid_agg_rx,
 536                                             int index,
 537                                             struct sk_buff_head *frames)
 538 {
 539         struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
 540
 541         if (!skb)
 542                 goto no_frame;
 543
 544         /* release the frame from the reorder ring buffer */
 545         tid_agg_rx->stored_mpdu_num--;
 546         tid_agg_rx->reorder_buf[index] = NULL;
 547         __skb_queue_tail(frames, skb);
 548
 549 no_frame:
 550         tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
 551 }
 552
 553 static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw,
 554                                              struct tid_ampdu_rx *tid_agg_rx,
 555                                              u16 head_seq_num,
 556                                              struct sk_buff_head *frames)
 557 {
 558         int index;
 559
 560         while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
 561                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
 562                                                         tid_agg_rx->buf_size;
 563                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames);
 564         }
 565 }
 566
 567 /*
 568  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
 569  * the skb was added to the buffer longer than this time ago, the earlier
 570  * frames that have not yet been received are assumed to be lost and the skb
 571  * can be released for processing. This may also release other skb's from the
 572  * reorder buffer if there are no additional gaps between the frames.
 573  *
 574  * Callers must hold tid_agg_rx->reorder_lock.
 575  */
 576 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
 577
 578 static void ieee80211_sta_reorder_release(struct ieee80211_hw *hw,
 579                                           struct tid_ampdu_rx *tid_agg_rx,
 580                                           struct sk_buff_head *frames)
 581 {
 582         int index, j;
 583
 584         /* release the buffer until next missing frame */
 585         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
 586                                                 tid_agg_rx->buf_size;
 587         if (!tid_agg_rx->reorder_buf[index] &&
 588             tid_agg_rx->stored_mpdu_num > 1) {
 589                 /*
 590                  * No buffers ready to be released, but check whether any
 591                  * frames in the reorder buffer have timed out.
 592                  */
 593                 int skipped = 1;
 594                 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
 595                      j = (j + 1) % tid_agg_rx->buf_size) {
 596                         if (!tid_agg_rx->reorder_buf[j]) {
 597                                 skipped++;
 598                                 continue;
 599                         }
 600                         if (!time_after(jiffies, tid_agg_rx->reorder_time[j] +
 601                                         HT_RX_REORDER_BUF_TIMEOUT))
 602                                 goto set_release_timer;
 603
 604 #ifdef CONFIG_MAC80211_HT_DEBUG
 605                         if (net_ratelimit())
 606                                 wiphy_debug(hw->wiphy,
 607                                             "release an RX reorder frame due to timeout on earlier frames\n");
 608 #endif
 609                         ieee80211_release_reorder_frame(hw, tid_agg_rx,
 610                                                         j, frames);
 611
 612                         /*
 613                          * Increment the head seq# also for the skipped slots.
 614                          */
 615                         tid_agg_rx->head_seq_num =
 616                                 (tid_agg_rx->head_seq_num + skipped) & SEQ_MASK;
 617                         skipped = 0;
 618                 }
 619         } else while (tid_agg_rx->reorder_buf[index]) {
 620                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames);
 621                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
 622                                                         tid_agg_rx->buf_size;
 623         }
 624
 625         if (tid_agg_rx->stored_mpdu_num) {
 626                 j = index = seq_sub(tid_agg_rx->head_seq_num,
 627                                     tid_agg_rx->ssn) % tid_agg_rx->buf_size;
 628
 629                 for (; j != (index - 1) % tid_agg_rx->buf_size;
 630                      j = (j + 1) % tid_agg_rx->buf_size) {
 631                         if (tid_agg_rx->reorder_buf[j])
 632                                 break;
 633                 }
 634
 635  set_release_timer:
 636
 637                 mod_timer(&tid_agg_rx->reorder_timer,
 638                           tid_agg_rx->reorder_time[j] +
 639                           HT_RX_REORDER_BUF_TIMEOUT);
 640         } else {
 641                 del_timer(&tid_agg_rx->reorder_timer);
 642         }
 643 }
 644
 645 /*
 646  * As this function belongs to the RX path it must be under
 647  * rcu_read_lock protection. It returns false if the frame
 648  * can be processed immediately, true if it was consumed.
 649  */
 650 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
 651                                              struct tid_ampdu_rx *tid_agg_rx,
 652                                              struct sk_buff *skb,
 653                                              struct sk_buff_head *frames)
 654 {
 655         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 656         u16 sc = le16_to_cpu(hdr->seq_ctrl);
 657         u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
 658         u16 head_seq_num, buf_size;
 659         int index;
 660         bool ret = true;
 661
 662         buf_size = tid_agg_rx->buf_size;
 663         head_seq_num = tid_agg_rx->head_seq_num;
 664
 665         spin_lock(&tid_agg_rx->reorder_lock);
 666         /* frame with out of date sequence number */
 667         if (seq_less(mpdu_seq_num, head_seq_num)) {
 668                 dev_kfree_skb(skb);
 669                 goto out;
 670         }
 671
 672         /*
 673          * If frame the sequence number exceeds our buffering window
 674          * size release some previous frames to make room for this one.
 675          */
 676         if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
 677                 head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
 678                 /* release stored frames up to new head to stack */
 679                 ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num,
 680                                                  frames);
 681         }
 682
 683         /* Now the new frame is always in the range of the reordering buffer */
 684
 685         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size;
 686
 687         /* check if we already stored this frame */
 688         if (tid_agg_rx->reorder_buf[index]) {
 689                 dev_kfree_skb(skb);
 690                 goto out;
 691         }
 692
 693         /*
 694          * If the current MPDU is in the right order and nothing else
 695          * is stored we can process it directly, no need to buffer it.
 696          */
 697         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
 698             tid_agg_rx->stored_mpdu_num == 0) {
 699                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
 700                 ret = false;
 701                 goto out;
 702         }
 703
 704         /* put the frame in the reordering buffer */
 705         tid_agg_rx->reorder_buf[index] = skb;
 706         tid_agg_rx->reorder_time[index] = jiffies;
 707         tid_agg_rx->stored_mpdu_num++;
 708         ieee80211_sta_reorder_release(hw, tid_agg_rx, frames);
 709
 710  out:
 711         spin_unlock(&tid_agg_rx->reorder_lock);
 712         return ret;
 713 }
 714
 715 /*
 716  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
 717  * true if the MPDU was buffered, false if it should be processed.
 718  */
 719 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
 720                                        struct sk_buff_head *frames)
 721 {
 722         struct sk_buff *skb = rx->skb;
 723         struct ieee80211_local *local = rx->local;
 724         struct ieee80211_hw *hw = &local->hw;
 725         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 726         struct sta_info *sta = rx->sta;
 727         struct tid_ampdu_rx *tid_agg_rx;
 728         u16 sc;
 729         int tid;
 730
 731         if (!ieee80211_is_data_qos(hdr->frame_control))
 732                 goto dont_reorder;
 733
 734         /*
 735          * filter the QoS data rx stream according to
 736          * STA/TID and check if this STA/TID is on aggregation
 737          */
 738
 739         if (!sta)
 740                 goto dont_reorder;
 741
 742         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
 743
 744         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
 745         if (!tid_agg_rx)
 746                 goto dont_reorder;
 747
 748         /* qos null data frames are excluded */
 749         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
 750                 goto dont_reorder;
 751
 752         /* new, potentially un-ordered, ampdu frame - process it */
 753
 754         /* reset session timer */
 755         if (tid_agg_rx->timeout)
 756                 mod_timer(&tid_agg_rx->session_timer,
 757                           TU_TO_EXP_TIME(tid_agg_rx->timeout));
 758
 759         /* if this mpdu is fragmented - terminate rx aggregation session */
 760         sc = le16_to_cpu(hdr->seq_ctrl);
 761         if (sc & IEEE80211_SCTL_FRAG) {
 762                 skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
 763                 skb_queue_tail(&rx->sdata->skb_queue, skb);
 764                 ieee80211_queue_work(&local->hw, &rx->sdata->work);
 765                 return;
 766         }
 767
 768         /*
 769          * No locking needed -- we will only ever process one
 770          * RX packet at a time, and thus own tid_agg_rx. All
 771          * other code manipulating it needs to (and does) make
 772          * sure that we cannot get to it any more before doing
 773          * anything with it.
 774          */
 775         if (ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb, frames))
 776                 return;
 777
 778  dont_reorder:
 779         __skb_queue_tail(frames, skb);
 780 }
 781
 782 static ieee80211_rx_result debug_noinline
 783 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
 784 {
 785         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 786         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 787
 788         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 789         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 790                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
 791                              rx->sta->last_seq_ctrl[rx->queue] ==
 792                              hdr->seq_ctrl)) {
 793                         if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
 794                                 rx->local->dot11FrameDuplicateCount++;
 795                                 rx->sta->num_duplicates++;
 796                         }
 797                         return RX_DROP_MONITOR;
 798                 } else
 799                         rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
 800         }
 801
 802         if (unlikely(rx->skb->len < 16)) {
 803                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 804                 return RX_DROP_MONITOR;
 805         }
 806
 807         /* Drop disallowed frame classes based on STA auth/assoc state;
 808          * IEEE 802.11, Chap 5.5.
 809          *
 810          * mac80211 filters only based on association state, i.e. it drops
 811          * Class 3 frames from not associated stations. hostapd sends
 812          * deauth/disassoc frames when needed. In addition, hostapd is
 813          * responsible for filtering on both auth and assoc states.
 814          */
 815
 816         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
 817                 return ieee80211_rx_mesh_check(rx);
 818
 819         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
 820                       ieee80211_is_pspoll(hdr->frame_control)) &&
 821                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
 822                      rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
 823                      (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
 824                 if ((!ieee80211_has_fromds(hdr->frame_control) &&
 825                      !ieee80211_has_tods(hdr->frame_control) &&
 826                      ieee80211_is_data(hdr->frame_control)) ||
 827                     !(status->rx_flags & IEEE80211_RX_RA_MATCH)) {
 828                         /* Drop IBSS frames and frames for other hosts
 829                          * silently. */
 830                         return RX_DROP_MONITOR;
 831                 }
 832
 833                 return RX_DROP_MONITOR;
 834         }
 835
 836         return RX_CONTINUE;
 837 }
 838
 839
 840 static ieee80211_rx_result debug_noinline
 841 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
 842 {
 843         struct sk_buff *skb = rx->skb;
 844         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 845         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 846         int keyidx;
 847         int hdrlen;
 848         ieee80211_rx_result result = RX_DROP_UNUSABLE;
 849         struct ieee80211_key *sta_ptk = NULL;
 850         int mmie_keyidx = -1;
 851         __le16 fc;
 852
 853         /*
 854          * Key selection 101
 855          *
 856          * There are four types of keys:
 857          *  - GTK (group keys)
 858          *  - IGTK (group keys for management frames)
 859          *  - PTK (pairwise keys)
 860          *  - STK (station-to-station pairwise keys)
 861          *
 862          * When selecting a key, we have to distinguish between multicast
 863          * (including broadcast) and unicast frames, the latter can only
 864          * use PTKs and STKs while the former always use GTKs and IGTKs.
 865          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
 866          * unicast frames can also use key indices like GTKs. Hence, if we
 867          * don't have a PTK/STK we check the key index for a WEP key.
 868          *
 869          * Note that in a regular BSS, multicast frames are sent by the
 870          * AP only, associated stations unicast the frame to the AP first
 871          * which then multicasts it on their behalf.
 872          *
 873          * There is also a slight problem in IBSS mode: GTKs are negotiated
 874          * with each station, that is something we don't currently handle.
 875          * The spec seems to expect that one negotiates the same key with
 876          * every station but there's no such requirement; VLANs could be
 877          * possible.
 878          */
 879
 880         /*
 881          * No point in finding a key and decrypting if the frame is neither
 882          * addressed to us nor a multicast frame.
 883          */
 884         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
 885                 return RX_CONTINUE;
 886
 887         /* start without a key */
 888         rx->key = NULL;
 889
 890         if (rx->sta)
 891                 sta_ptk = rcu_dereference(rx->sta->ptk);
 892
 893         fc = hdr->frame_control;
 894
 895         if (!ieee80211_has_protected(fc))
 896                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
 897
 898         if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
 899                 rx->key = sta_ptk;
 900                 if ((status->flag & RX_FLAG_DECRYPTED) &&
 901                     (status->flag & RX_FLAG_IV_STRIPPED))
 902                         return RX_CONTINUE;
 903                 /* Skip decryption if the frame is not protected. */
 904                 if (!ieee80211_has_protected(fc))
 905                         return RX_CONTINUE;
 906         } else if (mmie_keyidx >= 0) {
 907                 /* Broadcast/multicast robust management frame / BIP */
 908                 if ((status->flag & RX_FLAG_DECRYPTED) &&
 909                     (status->flag & RX_FLAG_IV_STRIPPED))
 910                         return RX_CONTINUE;
 911
 912                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
 913                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
 914                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
 915                 if (rx->sta)
 916                         rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
 917                 if (!rx->key)
 918                         rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
 919         } else if (!ieee80211_has_protected(fc)) {
 920                 /*
 921                  * The frame was not protected, so skip decryption. However, we
 922                  * need to set rx->key if there is a key that could have been
 923                  * used so that the frame may be dropped if encryption would
 924                  * have been expected.
 925                  */
 926                 struct ieee80211_key *key = NULL;
 927                 if (ieee80211_is_mgmt(fc) &&
 928                     is_multicast_ether_addr(hdr->addr1) &&
 929                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
 930                         rx->key = key;
 931                 else if ((key = rcu_dereference(rx->sdata->default_key)))
 932                         rx->key = key;
 933                 return RX_CONTINUE;
 934         } else {
 935                 u8 keyid;
 936                 /*
 937                  * The device doesn't give us the IV so we won't be
 938                  * able to look up the key. That's ok though, we
 939                  * don't need to decrypt the frame, we just won't
 940                  * be able to keep statistics accurate.
 941                  * Except for key threshold notifications, should
 942                  * we somehow allow the driver to tell us which key
 943                  * the hardware used if this flag is set?
 944                  */
 945                 if ((status->flag & RX_FLAG_DECRYPTED) &&
 946                     (status->flag & RX_FLAG_IV_STRIPPED))
 947                         return RX_CONTINUE;
 948
 949                 hdrlen = ieee80211_hdrlen(fc);
 950
 951                 if (rx->skb->len < 8 + hdrlen)
 952                         return RX_DROP_UNUSABLE; /* TODO: count this? */
 953
 954                 /*
 955                  * no need to call ieee80211_wep_get_keyidx,
 956                  * it verifies a bunch of things we've done already
 957                  */
 958                 skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
 959                 keyidx = keyid >> 6;
 960
 961                 /* check per-station GTK first, if multicast packet */
 962                 if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
 963                         rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
 964
 965                 /* if not found, try default key */
 966                 if (!rx->key) {
 967                         rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
 968
 969                         /*
 970                          * RSNA-protected unicast frames should always be
 971                          * sent with pairwise or station-to-station keys,
 972                          * but for WEP we allow using a key index as well.
 973                          */
 974                         if (rx->key &&
 975                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
 976                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
 977                             !is_multicast_ether_addr(hdr->addr1))
 978                                 rx->key = NULL;
 979                 }
 980         }
 981
 982         if (rx->key) {
 983                 rx->key->tx_rx_count++;
 984                 /* TODO: add threshold stuff again */
 985         } else {
 986                 return RX_DROP_MONITOR;
 987         }
 988
 989         if (skb_linearize(rx->skb))
 990                 return RX_DROP_UNUSABLE;
 991         /* the hdr variable is invalid now! */
 992
 993         switch (rx->key->conf.cipher) {
 994         case WLAN_CIPHER_SUITE_WEP40:
 995         case WLAN_CIPHER_SUITE_WEP104:
 996                 /* Check for weak IVs if possible */
 997                 if (rx->sta && ieee80211_is_data(fc) &&
 998                     (!(status->flag & RX_FLAG_IV_STRIPPED) ||
 999                      !(status->flag & RX_FLAG_DECRYPTED)) &&
1000                     ieee80211_wep_is_weak_iv(rx->skb, rx->key))
1001                         rx->sta->wep_weak_iv_count++;
1002
1003                 result = ieee80211_crypto_wep_decrypt(rx);
1004                 break;
1005         case WLAN_CIPHER_SUITE_TKIP:
1006                 result = ieee80211_crypto_tkip_decrypt(rx);
1007                 break;
1008         case WLAN_CIPHER_SUITE_CCMP:
1009                 result = ieee80211_crypto_ccmp_decrypt(rx);
1010                 break;
1011         case WLAN_CIPHER_SUITE_AES_CMAC:
1012                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
1013                 break;
1014         default:
1015                 /*
1016                  * We can reach here only with HW-only algorithms
1017                  * but why didn't it decrypt the frame?!
1018                  */
1019                 return RX_DROP_UNUSABLE;
1020         }
1021
1022         /* either the frame has been decrypted or will be dropped */
1023         status->flag |= RX_FLAG_DECRYPTED;
1024
1025         return result;
1026 }
1027
1028 static ieee80211_rx_result debug_noinline
1029 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1030 {
1031         struct ieee80211_local *local;
1032         struct ieee80211_hdr *hdr;
1033         struct sk_buff *skb;
1034
1035         local = rx->local;
1036         skb = rx->skb;
1037         hdr = (struct ieee80211_hdr *) skb->data;
1038
1039         if (!local->pspolling)
1040                 return RX_CONTINUE;
1041
1042         if (!ieee80211_has_fromds(hdr->frame_control))
1043                 /* this is not from AP */
1044                 return RX_CONTINUE;
1045
1046         if (!ieee80211_is_data(hdr->frame_control))
1047                 return RX_CONTINUE;
1048
1049         if (!ieee80211_has_moredata(hdr->frame_control)) {
1050                 /* AP has no more frames buffered for us */
1051                 local->pspolling = false;
1052                 return RX_CONTINUE;
1053         }
1054
1055         /* more data bit is set, let's request a new frame from the AP */
1056         ieee80211_send_pspoll(local, rx->sdata);
1057
1058         return RX_CONTINUE;
1059 }
1060
1061 static void ap_sta_ps_start(struct sta_info *sta)
1062 {
1063         struct ieee80211_sub_if_data *sdata = sta->sdata;
1064         struct ieee80211_local *local = sdata->local;
1065
1066         atomic_inc(&sdata->bss->num_sta_ps);
1067         set_sta_flags(sta, WLAN_STA_PS_STA);
1068         drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1069 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1070         printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
1071                sdata->name, sta->sta.addr, sta->sta.aid);
1072 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1073 }
1074
1075 static void ap_sta_ps_end(struct sta_info *sta)
1076 {
1077         struct ieee80211_sub_if_data *sdata = sta->sdata;
1078
1079         atomic_dec(&sdata->bss->num_sta_ps);
1080
1081         clear_sta_flags(sta, WLAN_STA_PS_STA);
1082
1083 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1084         printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
1085                sdata->name, sta->sta.addr, sta->sta.aid);
1086 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1087
1088         if (test_sta_flags(sta, WLAN_STA_PS_DRIVER)) {
1089 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1090                 printk(KERN_DEBUG "%s: STA %pM aid %d driver-ps-blocked\n",
1091                        sdata->name, sta->sta.addr, sta->sta.aid);
1092 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1093                 return;
1094         }
1095
1096         ieee80211_sta_ps_deliver_wakeup(sta);
1097 }
1098
1099 static ieee80211_rx_result debug_noinline
1100 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1101 {
1102         struct sta_info *sta = rx->sta;
1103         struct sk_buff *skb = rx->skb;
1104         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1105         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1106
1107         if (!sta)
1108                 return RX_CONTINUE;
1109
1110         /*
1111          * Update last_rx only for IBSS packets which are for the current
1112          * BSSID to avoid keeping the current IBSS network alive in cases
1113          * where other STAs start using different BSSID.
1114          */
1115         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1116                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1117                                                 NL80211_IFTYPE_ADHOC);
1118                 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0)
1119                         sta->last_rx = jiffies;
1120         } else if (!is_multicast_ether_addr(hdr->addr1)) {
1121                 /*
1122                  * Mesh beacons will update last_rx when if they are found to
1123                  * match the current local configuration when processed.
1124                  */
1125                 sta->last_rx = jiffies;
1126         }
1127
1128         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1129                 return RX_CONTINUE;
1130
1131         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1132                 ieee80211_sta_rx_notify(rx->sdata, hdr);
1133
1134         sta->rx_fragments++;
1135         sta->rx_bytes += rx->skb->len;
1136         sta->last_signal = status->signal;
1137
1138         /*
1139          * Change STA power saving mode only at the end of a frame
1140          * exchange sequence.
1141          */
1142         if (!ieee80211_has_morefrags(hdr->frame_control) &&
1143             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1144              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1145                 if (test_sta_flags(sta, WLAN_STA_PS_STA)) {
1146                         /*
1147                          * Ignore doze->wake transitions that are
1148                          * indicated by non-data frames, the standard
1149                          * is unclear here, but for example going to
1150                          * PS mode and then scanning would cause a
1151                          * doze->wake transition for the probe request,
1152                          * and that is clearly undesirable.
1153                          */
1154                         if (ieee80211_is_data(hdr->frame_control) &&
1155                             !ieee80211_has_pm(hdr->frame_control))
1156                                 ap_sta_ps_end(sta);
1157                 } else {
1158                         if (ieee80211_has_pm(hdr->frame_control))
1159                                 ap_sta_ps_start(sta);
1160                 }
1161         }
1162
1163         /*
1164          * Drop (qos-)data::nullfunc frames silently, since they
1165          * are used only to control station power saving mode.
1166          */
1167         if (ieee80211_is_nullfunc(hdr->frame_control) ||
1168             ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1169                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1170
1171                 /*
1172                  * If we receive a 4-addr nullfunc frame from a STA
1173                  * that was not moved to a 4-addr STA vlan yet, drop
1174                  * the frame to the monitor interface, to make sure
1175                  * that hostapd sees it
1176                  */
1177                 if (ieee80211_has_a4(hdr->frame_control) &&
1178                     (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1179                      (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1180                       !rx->sdata->u.vlan.sta)))
1181                         return RX_DROP_MONITOR;
1182                 /*
1183                  * Update counter and free packet here to avoid
1184                  * counting this as a dropped packed.
1185                  */
1186                 sta->rx_packets++;
1187                 dev_kfree_skb(rx->skb);
1188                 return RX_QUEUED;
1189         }
1190
1191         return RX_CONTINUE;
1192 } /* ieee80211_rx_h_sta_process */
1193
1194 static inline struct ieee80211_fragment_entry *
1195 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1196                          unsigned int frag, unsigned int seq, int rx_queue,
1197                          struct sk_buff **skb)
1198 {
1199         struct ieee80211_fragment_entry *entry;
1200         int idx;
1201
1202         idx = sdata->fragment_next;
1203         entry = &sdata->fragments[sdata->fragment_next++];
1204         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1205                 sdata->fragment_next = 0;
1206
1207         if (!skb_queue_empty(&entry->skb_list)) {
1208 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1209                 struct ieee80211_hdr *hdr =
1210                         (struct ieee80211_hdr *) entry->skb_list.next->data;
1211                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
1212                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
1213                        "addr1=%pM addr2=%pM\n",
1214                        sdata->name, idx,
1215                        jiffies - entry->first_frag_time, entry->seq,
1216                        entry->last_frag, hdr->addr1, hdr->addr2);
1217 #endif
1218                 __skb_queue_purge(&entry->skb_list);
1219         }
1220
1221         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1222         *skb = NULL;
1223         entry->first_frag_time = jiffies;
1224         entry->seq = seq;
1225         entry->rx_queue = rx_queue;
1226         entry->last_frag = frag;
1227         entry->ccmp = 0;
1228         entry->extra_len = 0;
1229
1230         return entry;
1231 }
1232
1233 static inline struct ieee80211_fragment_entry *
1234 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1235                           unsigned int frag, unsigned int seq,
1236                           int rx_queue, struct ieee80211_hdr *hdr)
1237 {
1238         struct ieee80211_fragment_entry *entry;
1239         int i, idx;
1240
1241         idx = sdata->fragment_next;
1242         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1243                 struct ieee80211_hdr *f_hdr;
1244
1245                 idx--;
1246                 if (idx < 0)
1247                         idx = IEEE80211_FRAGMENT_MAX - 1;
1248
1249                 entry = &sdata->fragments[idx];
1250                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1251                     entry->rx_queue != rx_queue ||
1252                     entry->last_frag + 1 != frag)
1253                         continue;
1254
1255                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1256
1257                 /*
1258                  * Check ftype and addresses are equal, else check next fragment
1259                  */
1260                 if (((hdr->frame_control ^ f_hdr->frame_control) &
1261                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1262                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
1263                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
1264                         continue;
1265
1266                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1267                         __skb_queue_purge(&entry->skb_list);
1268                         continue;
1269                 }
1270                 return entry;
1271         }
1272
1273         return NULL;
1274 }
1275
1276 static ieee80211_rx_result debug_noinline
1277 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1278 {
1279         struct ieee80211_hdr *hdr;
1280         u16 sc;
1281         __le16 fc;
1282         unsigned int frag, seq;
1283         struct ieee80211_fragment_entry *entry;
1284         struct sk_buff *skb;
1285         struct ieee80211_rx_status *status;
1286
1287         hdr = (struct ieee80211_hdr *)rx->skb->data;
1288         fc = hdr->frame_control;
1289         sc = le16_to_cpu(hdr->seq_ctrl);
1290         frag = sc & IEEE80211_SCTL_FRAG;
1291
1292         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1293                    (rx->skb)->len < 24 ||
1294                    is_multicast_ether_addr(hdr->addr1))) {
1295                 /* not fragmented */
1296                 goto out;
1297         }
1298         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1299
1300         if (skb_linearize(rx->skb))
1301                 return RX_DROP_UNUSABLE;
1302
1303         /*
1304          *  skb_linearize() might change the skb->data and
1305          *  previously cached variables (in this case, hdr) need to
1306          *  be refreshed with the new data.
1307          */
1308         hdr = (struct ieee80211_hdr *)rx->skb->data;
1309         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1310
1311         if (frag == 0) {
1312                 /* This is the first fragment of a new frame. */
1313                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1314                                                  rx->queue, &(rx->skb));
1315                 if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP &&
1316                     ieee80211_has_protected(fc)) {
1317                         int queue = ieee80211_is_mgmt(fc) ?
1318                                 NUM_RX_DATA_QUEUES : rx->queue;
1319                         /* Store CCMP PN so that we can verify that the next
1320                          * fragment has a sequential PN value. */
1321                         entry->ccmp = 1;
1322                         memcpy(entry->last_pn,
1323                                rx->key->u.ccmp.rx_pn[queue],
1324                                CCMP_PN_LEN);
1325                 }
1326                 return RX_QUEUED;
1327         }
1328
1329         /* This is a fragment for a frame that should already be pending in
1330          * fragment cache. Add this fragment to the end of the pending entry.
1331          */
1332         entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
1333         if (!entry) {
1334                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1335                 return RX_DROP_MONITOR;
1336         }
1337
1338         /* Verify that MPDUs within one MSDU have sequential PN values.
1339          * (IEEE 802.11i, 8.3.3.4.5) */
1340         if (entry->ccmp) {
1341                 int i;
1342                 u8 pn[CCMP_PN_LEN], *rpn;
1343                 int queue;
1344                 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP)
1345                         return RX_DROP_UNUSABLE;
1346                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1347                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1348                         pn[i]++;
1349                         if (pn[i])
1350                                 break;
1351                 }
1352                 queue = ieee80211_is_mgmt(fc) ?
1353                         NUM_RX_DATA_QUEUES : rx->queue;
1354                 rpn = rx->key->u.ccmp.rx_pn[queue];
1355                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1356                         return RX_DROP_UNUSABLE;
1357                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1358         }
1359
1360         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1361         __skb_queue_tail(&entry->skb_list, rx->skb);
1362         entry->last_frag = frag;
1363         entry->extra_len += rx->skb->len;
1364         if (ieee80211_has_morefrags(fc)) {
1365                 rx->skb = NULL;
1366                 return RX_QUEUED;
1367         }
1368
1369         rx->skb = __skb_dequeue(&entry->skb_list);
1370         if (skb_tailroom(rx->skb) < entry->extra_len) {
1371                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1372                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1373                                               GFP_ATOMIC))) {
1374                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1375                         __skb_queue_purge(&entry->skb_list);
1376                         return RX_DROP_UNUSABLE;
1377                 }
1378         }
1379         while ((skb = __skb_dequeue(&entry->skb_list))) {
1380                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1381                 dev_kfree_skb(skb);
1382         }
1383
1384         /* Complete frame has been reassembled - process it now */
1385         status = IEEE80211_SKB_RXCB(rx->skb);
1386         status->rx_flags |= IEEE80211_RX_FRAGMENTED;
1387
1388  out:
1389         if (rx->sta)
1390                 rx->sta->rx_packets++;
1391         if (is_multicast_ether_addr(hdr->addr1))
1392                 rx->local->dot11MulticastReceivedFrameCount++;
1393         else
1394                 ieee80211_led_rx(rx->local);
1395         return RX_CONTINUE;
1396 }
1397
1398 static ieee80211_rx_result debug_noinline
1399 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
1400 {
1401         struct ieee80211_sub_if_data *sdata = rx->sdata;
1402         __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
1403         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1404
1405         if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
1406                    !(status->rx_flags & IEEE80211_RX_RA_MATCH)))
1407                 return RX_CONTINUE;
1408
1409         if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1410             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1411                 return RX_DROP_UNUSABLE;
1412
1413         if (!test_sta_flags(rx->sta, WLAN_STA_PS_DRIVER))
1414                 ieee80211_sta_ps_deliver_poll_response(rx->sta);
1415         else
1416                 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1417
1418         /* Free PS Poll skb here instead of returning RX_DROP that would
1419          * count as an dropped frame. */
1420         dev_kfree_skb(rx->skb);
1421
1422         return RX_QUEUED;
1423 }
1424
1425 static ieee80211_rx_result debug_noinline
1426 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1427 {
1428         u8 *data = rx->skb->data;
1429         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1430
1431         if (!ieee80211_is_data_qos(hdr->frame_control))
1432                 return RX_CONTINUE;
1433
1434         /* remove the qos control field, update frame type and meta-data */
1435         memmove(data + IEEE80211_QOS_CTL_LEN, data,
1436                 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1437         hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1438         /* change frame type to non QOS */
1439         hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1440
1441         return RX_CONTINUE;
1442 }
1443
1444 static int
1445 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1446 {
1447         if (unlikely(!rx->sta ||
1448             !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1449                 return -EACCES;
1450
1451         return 0;
1452 }
1453
1454 static int
1455 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1456 {
1457         struct sk_buff *skb = rx->skb;
1458         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1459
1460         /*
1461          * Pass through unencrypted frames if the hardware has
1462          * decrypted them already.
1463          */
1464         if (status->flag & RX_FLAG_DECRYPTED)
1465                 return 0;
1466
1467         /* Drop unencrypted frames if key is set. */
1468         if (unlikely(!ieee80211_has_protected(fc) &&
1469                      !ieee80211_is_nullfunc(fc) &&
1470                      ieee80211_is_data(fc) &&
1471                      (rx->key || rx->sdata->drop_unencrypted)))
1472                 return -EACCES;
1473
1474         return 0;
1475 }
1476
1477 static int
1478 ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1479 {
1480         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1481         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1482         __le16 fc = hdr->frame_control;
1483
1484         /*
1485          * Pass through unencrypted frames if the hardware has
1486          * decrypted them already.
1487          */
1488         if (status->flag & RX_FLAG_DECRYPTED)
1489                 return 0;
1490
1491         if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) {
1492                 if (unlikely(!ieee80211_has_protected(fc) &&
1493                              ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1494                              rx->key))
1495                         return -EACCES;
1496                 /* BIP does not use Protected field, so need to check MMIE */
1497                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1498                              ieee80211_get_mmie_keyidx(rx->skb) < 0))
1499                         return -EACCES;
1500                 /*
1501                  * When using MFP, Action frames are not allowed prior to
1502                  * having configured keys.
1503                  */
1504                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1505                              ieee80211_is_robust_mgmt_frame(
1506                                      (struct ieee80211_hdr *) rx->skb->data)))
1507                         return -EACCES;
1508         }
1509
1510         return 0;
1511 }
1512
1513 static int
1514 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1515 {
1516         struct ieee80211_sub_if_data *sdata = rx->sdata;
1517         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1518
1519         if (ieee80211_has_a4(hdr->frame_control) &&
1520             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1521                 return -1;
1522
1523         if (is_multicast_ether_addr(hdr->addr1) &&
1524             ((sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta) ||
1525              (sdata->vif.type == NL80211_IFTYPE_STATION && sdata->u.mgd.use_4addr)))
1526                 return -1;
1527
1528         return ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1529 }
1530
1531 /*
1532  * requires that rx->skb is a frame with ethernet header
1533  */
1534 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1535 {
1536         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1537                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1538         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1539
1540         /*
1541          * Allow EAPOL frames to us/the PAE group address regardless
1542          * of whether the frame was encrypted or not.
1543          */
1544         if (ehdr->h_proto == rx->sdata->control_port_protocol &&
1545             (compare_ether_addr(ehdr->h_dest, rx->sdata->vif.addr) == 0 ||
1546              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1547                 return true;
1548
1549         if (ieee80211_802_1x_port_control(rx) ||
1550             ieee80211_drop_unencrypted(rx, fc))
1551                 return false;
1552
1553         return true;
1554 }
1555
1556 /*
1557  * requires that rx->skb is a frame with ethernet header
1558  */
1559 static void
1560 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1561 {
1562         struct ieee80211_sub_if_data *sdata = rx->sdata;
1563         struct net_device *dev = sdata->dev;
1564         struct sk_buff *skb, *xmit_skb;
1565         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1566         struct sta_info *dsta;
1567         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1568
1569         skb = rx->skb;
1570         xmit_skb = NULL;
1571
1572         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1573              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1574             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1575             (status->rx_flags & IEEE80211_RX_RA_MATCH) &&
1576             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1577                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1578                         /*
1579                          * send multicast frames both to higher layers in
1580                          * local net stack and back to the wireless medium
1581                          */
1582                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1583                         if (!xmit_skb && net_ratelimit())
1584                                 printk(KERN_DEBUG "%s: failed to clone "
1585                                        "multicast frame\n", dev->name);
1586                 } else {
1587                         dsta = sta_info_get(sdata, skb->data);
1588                         if (dsta) {
1589                                 /*
1590                                  * The destination station is associated to
1591                                  * this AP (in this VLAN), so send the frame
1592                                  * directly to it and do not pass it to local
1593                                  * net stack.
1594                                  */
1595                                 xmit_skb = skb;
1596                                 skb = NULL;
1597                         }
1598                 }
1599         }
1600
1601         if (skb) {
1602                 int align __maybe_unused;
1603
1604 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1605                 /*
1606                  * 'align' will only take the values 0 or 2 here
1607                  * since all frames are required to be aligned
1608                  * to 2-byte boundaries when being passed to
1609                  * mac80211. That also explains the __skb_push()
1610                  * below.
1611                  */
1612                 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1613                 if (align) {
1614                         if (WARN_ON(skb_headroom(skb) < 3)) {
1615                                 dev_kfree_skb(skb);
1616                                 skb = NULL;
1617                         } else {
1618                                 u8 *data = skb->data;
1619                                 size_t len = skb_headlen(skb);
1620                                 skb->data -= align;
1621                                 memmove(skb->data, data, len);
1622                                 skb_set_tail_pointer(skb, len);
1623                         }
1624                 }
1625 #endif
1626
1627                 if (skb) {
1628                         /* deliver to local stack */
1629                         skb->protocol = eth_type_trans(skb, dev);
1630                         memset(skb->cb, 0, sizeof(skb->cb));
1631                         netif_receive_skb(skb);
1632                 }
1633         }
1634
1635         if (xmit_skb) {
1636                 /* send to wireless media */
1637                 xmit_skb->protocol = htons(ETH_P_802_3);
1638                 skb_reset_network_header(xmit_skb);
1639                 skb_reset_mac_header(xmit_skb);
1640                 dev_queue_xmit(xmit_skb);
1641         }
1642 }
1643
1644 static ieee80211_rx_result debug_noinline
1645 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1646 {
1647         struct net_device *dev = rx->sdata->dev;
1648         struct sk_buff *skb = rx->skb;
1649         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1650         __le16 fc = hdr->frame_control;
1651         struct sk_buff_head frame_list;
1652         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1653
1654         if (unlikely(!ieee80211_is_data(fc)))
1655                 return RX_CONTINUE;
1656
1657         if (unlikely(!ieee80211_is_data_present(fc)))
1658                 return RX_DROP_MONITOR;
1659
1660         if (!(status->rx_flags & IEEE80211_RX_AMSDU))
1661                 return RX_CONTINUE;
1662
1663         if (ieee80211_has_a4(hdr->frame_control) &&
1664             rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1665             !rx->sdata->u.vlan.sta)
1666                 return RX_DROP_UNUSABLE;
1667
1668         if (is_multicast_ether_addr(hdr->addr1) &&
1669             ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1670               rx->sdata->u.vlan.sta) ||
1671              (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1672               rx->sdata->u.mgd.use_4addr)))
1673                 return RX_DROP_UNUSABLE;
1674
1675         skb->dev = dev;
1676         __skb_queue_head_init(&frame_list);
1677
1678         if (skb_linearize(skb))
1679                 return RX_DROP_UNUSABLE;
1680
1681         ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1682                                  rx->sdata->vif.type,
1683                                  rx->local->hw.extra_tx_headroom);
1684
1685         while (!skb_queue_empty(&frame_list)) {
1686                 rx->skb = __skb_dequeue(&frame_list);
1687
1688                 if (!ieee80211_frame_allowed(rx, fc)) {
1689                         dev_kfree_skb(rx->skb);
1690                         continue;
1691                 }
1692                 dev->stats.rx_packets++;
1693                 dev->stats.rx_bytes += rx->skb->len;
1694
1695                 ieee80211_deliver_skb(rx);
1696         }
1697
1698         return RX_QUEUED;
1699 }
1700
1701 #ifdef CONFIG_MAC80211_MESH
1702 static ieee80211_rx_result
1703 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1704 {
1705         struct ieee80211_hdr *hdr;
1706         struct ieee80211s_hdr *mesh_hdr;
1707         unsigned int hdrlen;
1708         struct sk_buff *skb = rx->skb, *fwd_skb;
1709         struct ieee80211_local *local = rx->local;
1710         struct ieee80211_sub_if_data *sdata = rx->sdata;
1711         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1712
1713         hdr = (struct ieee80211_hdr *) skb->data;
1714         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1715         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1716
1717         if (!ieee80211_is_data(hdr->frame_control))
1718                 return RX_CONTINUE;
1719
1720         if (!mesh_hdr->ttl)
1721                 /* illegal frame */
1722                 return RX_DROP_MONITOR;
1723
1724         if (mesh_hdr->flags & MESH_FLAGS_AE) {
1725                 struct mesh_path *mppath;
1726                 char *proxied_addr;
1727                 char *mpp_addr;
1728
1729                 if (is_multicast_ether_addr(hdr->addr1)) {
1730                         mpp_addr = hdr->addr3;
1731                         proxied_addr = mesh_hdr->eaddr1;
1732                 } else {
1733                         mpp_addr = hdr->addr4;
1734                         proxied_addr = mesh_hdr->eaddr2;
1735                 }
1736
1737                 rcu_read_lock();
1738                 mppath = mpp_path_lookup(proxied_addr, sdata);
1739                 if (!mppath) {
1740                         mpp_path_add(proxied_addr, mpp_addr, sdata);
1741                 } else {
1742                         spin_lock_bh(&mppath->state_lock);
1743                         if (compare_ether_addr(mppath->mpp, mpp_addr) != 0)
1744                                 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
1745                         spin_unlock_bh(&mppath->state_lock);
1746                 }
1747                 rcu_read_unlock();
1748         }
1749
1750         /* Frame has reached destination.  Don't forward */
1751         if (!is_multicast_ether_addr(hdr->addr1) &&
1752             compare_ether_addr(sdata->vif.addr, hdr->addr3) == 0)
1753                 return RX_CONTINUE;
1754
1755         mesh_hdr->ttl--;
1756
1757         if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
1758                 if (!mesh_hdr->ttl)
1759                         IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1760                                                      dropped_frames_ttl);
1761                 else {
1762                         struct ieee80211_hdr *fwd_hdr;
1763                         struct ieee80211_tx_info *info;
1764
1765                         fwd_skb = skb_copy(skb, GFP_ATOMIC);
1766
1767                         if (!fwd_skb && net_ratelimit())
1768                                 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1769                                                    sdata->name);
1770
1771                         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1772                         memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
1773                         info = IEEE80211_SKB_CB(fwd_skb);
1774                         memset(info, 0, sizeof(*info));
1775                         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1776                         info->control.vif = &rx->sdata->vif;
1777                         skb_set_queue_mapping(skb,
1778                                 ieee80211_select_queue(rx->sdata, fwd_skb));
1779                         ieee80211_set_qos_hdr(local, skb);
1780                         if (is_multicast_ether_addr(fwd_hdr->addr1))
1781                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1782                                                                 fwded_mcast);
1783                         else {
1784                                 int err;
1785                                 /*
1786                                  * Save TA to addr1 to send TA a path error if a
1787                                  * suitable next hop is not found
1788                                  */
1789                                 memcpy(fwd_hdr->addr1, fwd_hdr->addr2,
1790                                                 ETH_ALEN);
1791                                 err = mesh_nexthop_lookup(fwd_skb, sdata);
1792                                 /* Failed to immediately resolve next hop:
1793                                  * fwded frame was dropped or will be added
1794                                  * later to the pending skb queue.  */
1795                                 if (err)
1796                                         return RX_DROP_MONITOR;
1797
1798                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1799                                                                 fwded_unicast);
1800                         }
1801                         IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1802                                                      fwded_frames);
1803                         ieee80211_add_pending_skb(local, fwd_skb);
1804                 }
1805         }
1806
1807         if (is_multicast_ether_addr(hdr->addr1) ||
1808             sdata->dev->flags & IFF_PROMISC)
1809                 return RX_CONTINUE;
1810         else
1811                 return RX_DROP_MONITOR;
1812 }
1813 #endif
1814
1815 static ieee80211_rx_result debug_noinline
1816 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1817 {
1818         struct ieee80211_sub_if_data *sdata = rx->sdata;
1819         struct ieee80211_local *local = rx->local;
1820         struct net_device *dev = sdata->dev;
1821         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1822         __le16 fc = hdr->frame_control;
1823         int err;
1824
1825         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1826                 return RX_CONTINUE;
1827
1828         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1829                 return RX_DROP_MONITOR;
1830
1831         /*
1832          * Allow the cooked monitor interface of an AP to see 4-addr frames so
1833          * that a 4-addr station can be detected and moved into a separate VLAN
1834          */
1835         if (ieee80211_has_a4(hdr->frame_control) &&
1836             sdata->vif.type == NL80211_IFTYPE_AP)
1837                 return RX_DROP_MONITOR;
1838
1839         err = __ieee80211_data_to_8023(rx);
1840         if (unlikely(err))
1841                 return RX_DROP_UNUSABLE;
1842
1843         if (!ieee80211_frame_allowed(rx, fc))
1844                 return RX_DROP_MONITOR;
1845
1846         rx->skb->dev = dev;
1847
1848         dev->stats.rx_packets++;
1849         dev->stats.rx_bytes += rx->skb->len;
1850
1851         if (ieee80211_is_data(hdr->frame_control) &&
1852             !is_multicast_ether_addr(hdr->addr1) &&
1853             local->hw.conf.dynamic_ps_timeout > 0 && local->ps_sdata) {
1854                         mod_timer(&local->dynamic_ps_timer, jiffies +
1855                          msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
1856         }
1857
1858         ieee80211_deliver_skb(rx);
1859
1860         return RX_QUEUED;
1861 }
1862
1863 static ieee80211_rx_result debug_noinline
1864 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
1865 {
1866         struct ieee80211_local *local = rx->local;
1867         struct ieee80211_hw *hw = &local->hw;
1868         struct sk_buff *skb = rx->skb;
1869         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1870         struct tid_ampdu_rx *tid_agg_rx;
1871         u16 start_seq_num;
1872         u16 tid;
1873
1874         if (likely(!ieee80211_is_ctl(bar->frame_control)))
1875                 return RX_CONTINUE;
1876
1877         if (ieee80211_is_back_req(bar->frame_control)) {
1878                 struct {
1879                         __le16 control, start_seq_num;
1880                 } __packed bar_data;
1881
1882                 if (!rx->sta)
1883                         return RX_DROP_MONITOR;
1884
1885                 if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
1886                                   &bar_data, sizeof(bar_data)))
1887                         return RX_DROP_MONITOR;
1888
1889                 tid = le16_to_cpu(bar_data.control) >> 12;
1890
1891                 tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
1892                 if (!tid_agg_rx)
1893                         return RX_DROP_MONITOR;
1894
1895                 start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
1896
1897                 /* reset session timer */
1898                 if (tid_agg_rx->timeout)
1899                         mod_timer(&tid_agg_rx->session_timer,
1900                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
1901
1902                 /* release stored frames up to start of BAR */
1903                 ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num,
1904                                                  frames);
1905                 kfree_skb(skb);
1906                 return RX_QUEUED;
1907         }
1908
1909         /*
1910          * After this point, we only want management frames,
1911          * so we can drop all remaining control frames to
1912          * cooked monitor interfaces.
1913          */
1914         return RX_DROP_MONITOR;
1915 }
1916
1917 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
1918                                            struct ieee80211_mgmt *mgmt,
1919                                            size_t len)
1920 {
1921         struct ieee80211_local *local = sdata->local;
1922         struct sk_buff *skb;
1923         struct ieee80211_mgmt *resp;
1924
1925         if (compare_ether_addr(mgmt->da, sdata->vif.addr) != 0) {
1926                 /* Not to own unicast address */
1927                 return;
1928         }
1929
1930         if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
1931             compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
1932                 /* Not from the current AP or not associated yet. */
1933                 return;
1934         }
1935
1936         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
1937                 /* Too short SA Query request frame */
1938                 return;
1939         }
1940
1941         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
1942         if (skb == NULL)
1943                 return;
1944
1945         skb_reserve(skb, local->hw.extra_tx_headroom);
1946         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
1947         memset(resp, 0, 24);
1948         memcpy(resp->da, mgmt->sa, ETH_ALEN);
1949         memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
1950         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
1951         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1952                                           IEEE80211_STYPE_ACTION);
1953         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
1954         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
1955         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
1956         memcpy(resp->u.action.u.sa_query.trans_id,
1957                mgmt->u.action.u.sa_query.trans_id,
1958                WLAN_SA_QUERY_TR_ID_LEN);
1959
1960         ieee80211_tx_skb(sdata, skb);
1961 }
1962
1963 static ieee80211_rx_result debug_noinline
1964 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
1965 {
1966         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1967         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1968
1969         /*
1970          * From here on, look only at management frames.
1971          * Data and control frames are already handled,
1972          * and unknown (reserved) frames are useless.
1973          */
1974         if (rx->skb->len < 24)
1975                 return RX_DROP_MONITOR;
1976
1977         if (!ieee80211_is_mgmt(mgmt->frame_control))
1978                 return RX_DROP_MONITOR;
1979
1980         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1981                 return RX_DROP_MONITOR;
1982
1983         if (ieee80211_drop_unencrypted_mgmt(rx))
1984                 return RX_DROP_UNUSABLE;
1985
1986         return RX_CONTINUE;
1987 }
1988
1989 static ieee80211_rx_result debug_noinline
1990 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
1991 {
1992         struct ieee80211_local *local = rx->local;
1993         struct ieee80211_sub_if_data *sdata = rx->sdata;
1994         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1995         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1996         int len = rx->skb->len;
1997
1998         if (!ieee80211_is_action(mgmt->frame_control))
1999                 return RX_CONTINUE;
2000
2001         /* drop too small frames */
2002         if (len < IEEE80211_MIN_ACTION_SIZE)
2003                 return RX_DROP_UNUSABLE;
2004
2005         if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC)
2006                 return RX_DROP_UNUSABLE;
2007
2008         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2009                 return RX_DROP_UNUSABLE;
2010
2011         switch (mgmt->u.action.category) {
2012         case WLAN_CATEGORY_BACK:
2013                 /*
2014                  * The aggregation code is not prepared to handle
2015                  * anything but STA/AP due to the BSSID handling;
2016                  * IBSS could work in the code but isn't supported
2017                  * by drivers or the standard.
2018                  */
2019                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2020                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2021                     sdata->vif.type != NL80211_IFTYPE_AP)
2022                         break;
2023
2024                 /* verify action_code is present */
2025                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2026                         break;
2027
2028                 switch (mgmt->u.action.u.addba_req.action_code) {
2029                 case WLAN_ACTION_ADDBA_REQ:
2030                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2031                                    sizeof(mgmt->u.action.u.addba_req)))
2032                                 goto invalid;
2033                         break;
2034                 case WLAN_ACTION_ADDBA_RESP:
2035                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2036                                    sizeof(mgmt->u.action.u.addba_resp)))
2037                                 goto invalid;
2038                         break;
2039                 case WLAN_ACTION_DELBA:
2040                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2041                                    sizeof(mgmt->u.action.u.delba)))
2042                                 goto invalid;
2043                         break;
2044                 default:
2045                         goto invalid;
2046                 }
2047
2048                 goto queue;
2049         case WLAN_CATEGORY_SPECTRUM_MGMT:
2050                 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
2051                         break;
2052
2053                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2054                         break;
2055
2056                 /* verify action_code is present */
2057                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2058                         break;
2059
2060                 switch (mgmt->u.action.u.measurement.action_code) {
2061                 case WLAN_ACTION_SPCT_MSR_REQ:
2062                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2063                                    sizeof(mgmt->u.action.u.measurement)))
2064                                 break;
2065                         ieee80211_process_measurement_req(sdata, mgmt, len);
2066                         goto handled;
2067                 case WLAN_ACTION_SPCT_CHL_SWITCH:
2068                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2069                                    sizeof(mgmt->u.action.u.chan_switch)))
2070                                 break;
2071
2072                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2073                                 break;
2074
2075                         if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
2076                                 break;
2077
2078                         goto queue;
2079                 }
2080                 break;
2081         case WLAN_CATEGORY_SA_QUERY:
2082                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2083                            sizeof(mgmt->u.action.u.sa_query)))
2084                         break;
2085
2086                 switch (mgmt->u.action.u.sa_query.action) {
2087                 case WLAN_ACTION_SA_QUERY_REQUEST:
2088                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2089                                 break;
2090                         ieee80211_process_sa_query_req(sdata, mgmt, len);
2091                         goto handled;
2092                 }
2093                 break;
2094         case WLAN_CATEGORY_MESH_PLINK:
2095         case WLAN_CATEGORY_MESH_PATH_SEL:
2096                 if (!ieee80211_vif_is_mesh(&sdata->vif))
2097                         break;
2098                 goto queue;
2099         }
2100
2101         return RX_CONTINUE;
2102
2103  invalid:
2104         status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
2105         /* will return in the next handlers */
2106         return RX_CONTINUE;
2107
2108  handled:
2109         if (rx->sta)
2110                 rx->sta->rx_packets++;
2111         dev_kfree_skb(rx->skb);
2112         return RX_QUEUED;
2113
2114  queue:
2115         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2116         skb_queue_tail(&sdata->skb_queue, rx->skb);
2117         ieee80211_queue_work(&local->hw, &sdata->work);
2118         if (rx->sta)
2119                 rx->sta->rx_packets++;
2120         return RX_QUEUED;
2121 }
2122
2123 static ieee80211_rx_result debug_noinline
2124 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
2125 {
2126         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2127
2128         /* skip known-bad action frames and return them in the next handler */
2129         if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
2130                 return RX_CONTINUE;
2131
2132         /*
2133          * Getting here means the kernel doesn't know how to handle
2134          * it, but maybe userspace does ... include returned frames
2135          * so userspace can register for those to know whether ones
2136          * it transmitted were processed or returned.
2137          */
2138
2139         if (cfg80211_rx_mgmt(rx->sdata->dev, status->freq,
2140                              rx->skb->data, rx->skb->len,
2141                              GFP_ATOMIC)) {
2142                 if (rx->sta)
2143                         rx->sta->rx_packets++;
2144                 dev_kfree_skb(rx->skb);
2145                 return RX_QUEUED;
2146         }
2147
2148
2149         return RX_CONTINUE;
2150 }
2151
2152 static ieee80211_rx_result debug_noinline
2153 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
2154 {
2155         struct ieee80211_local *local = rx->local;
2156         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2157         struct sk_buff *nskb;
2158         struct ieee80211_sub_if_data *sdata = rx->sdata;
2159         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2160
2161         if (!ieee80211_is_action(mgmt->frame_control))
2162                 return RX_CONTINUE;
2163
2164         /*
2165          * For AP mode, hostapd is responsible for handling any action
2166          * frames that we didn't handle, including returning unknown
2167          * ones. For all other modes we will return them to the sender,
2168          * setting the 0x80 bit in the action category, as required by
2169          * 802.11-2007 7.3.1.11.
2170          * Newer versions of hostapd shall also use the management frame
2171          * registration mechanisms, but older ones still use cooked
2172          * monitor interfaces so push all frames there.
2173          */
2174         if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
2175             (sdata->vif.type == NL80211_IFTYPE_AP ||
2176              sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
2177                 return RX_DROP_MONITOR;
2178
2179         /* do not return rejected action frames */
2180         if (mgmt->u.action.category & 0x80)
2181                 return RX_DROP_UNUSABLE;
2182
2183         nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2184                                GFP_ATOMIC);
2185         if (nskb) {
2186                 struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
2187
2188                 nmgmt->u.action.category |= 0x80;
2189                 memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
2190                 memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2191
2192                 memset(nskb->cb, 0, sizeof(nskb->cb));
2193
2194                 ieee80211_tx_skb(rx->sdata, nskb);
2195         }
2196         dev_kfree_skb(rx->skb);
2197         return RX_QUEUED;
2198 }
2199
2200 static ieee80211_rx_result debug_noinline
2201 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2202 {
2203         struct ieee80211_sub_if_data *sdata = rx->sdata;
2204         ieee80211_rx_result rxs;
2205         struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2206         __le16 stype;
2207
2208         rxs = ieee80211_work_rx_mgmt(rx->sdata, rx->skb);
2209         if (rxs != RX_CONTINUE)
2210                 return rxs;
2211
2212         stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2213
2214         if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2215             sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2216             sdata->vif.type != NL80211_IFTYPE_STATION)
2217                 return RX_DROP_MONITOR;
2218
2219         switch (stype) {
2220         case cpu_to_le16(IEEE80211_STYPE_BEACON):
2221         case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2222                 /* process for all: mesh, mlme, ibss */
2223                 break;
2224         case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2225         case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2226                 /* process only for station */
2227                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2228                         return RX_DROP_MONITOR;
2229                 break;
2230         case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2231         case cpu_to_le16(IEEE80211_STYPE_AUTH):
2232                 /* process only for ibss */
2233                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
2234                         return RX_DROP_MONITOR;
2235                 break;
2236         default:
2237                 return RX_DROP_MONITOR;
2238         }
2239
2240         /* queue up frame and kick off work to process it */
2241         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2242         skb_queue_tail(&sdata->skb_queue, rx->skb);
2243         ieee80211_queue_work(&rx->local->hw, &sdata->work);
2244         if (rx->sta)
2245                 rx->sta->rx_packets++;
2246
2247         return RX_QUEUED;
2248 }
2249
2250 static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr,
2251                                             struct ieee80211_rx_data *rx)
2252 {
2253         int keyidx;
2254         unsigned int hdrlen;
2255
2256         hdrlen = ieee80211_hdrlen(hdr->frame_control);
2257         if (rx->skb->len >= hdrlen + 4)
2258                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
2259         else
2260                 keyidx = -1;
2261
2262         if (!rx->sta) {
2263                 /*
2264                  * Some hardware seem to generate incorrect Michael MIC
2265                  * reports; ignore them to avoid triggering countermeasures.
2266                  */
2267                 return;
2268         }
2269
2270         if (!ieee80211_has_protected(hdr->frame_control))
2271                 return;
2272
2273         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
2274                 /*
2275                  * APs with pairwise keys should never receive Michael MIC
2276                  * errors for non-zero keyidx because these are reserved for
2277                  * group keys and only the AP is sending real multicast
2278                  * frames in the BSS.
2279                  */
2280                 return;
2281         }
2282
2283         if (!ieee80211_is_data(hdr->frame_control) &&
2284             !ieee80211_is_auth(hdr->frame_control))
2285                 return;
2286
2287         mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL,
2288                                         GFP_ATOMIC);
2289 }
2290
2291 /* TODO: use IEEE80211_RX_FRAGMENTED */
2292 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2293                                         struct ieee80211_rate *rate)
2294 {
2295         struct ieee80211_sub_if_data *sdata;
2296         struct ieee80211_local *local = rx->local;
2297         struct ieee80211_rtap_hdr {
2298                 struct ieee80211_radiotap_header hdr;
2299                 u8 flags;
2300                 u8 rate_or_pad;
2301                 __le16 chan_freq;
2302                 __le16 chan_flags;
2303         } __packed *rthdr;
2304         struct sk_buff *skb = rx->skb, *skb2;
2305         struct net_device *prev_dev = NULL;
2306         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2307
2308         /*
2309          * If cooked monitor has been processed already, then
2310          * don't do it again. If not, set the flag.
2311          */
2312         if (rx->flags & IEEE80211_RX_CMNTR)
2313                 goto out_free_skb;
2314         rx->flags |= IEEE80211_RX_CMNTR;
2315
2316         if (skb_headroom(skb) < sizeof(*rthdr) &&
2317             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
2318                 goto out_free_skb;
2319
2320         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
2321         memset(rthdr, 0, sizeof(*rthdr));
2322         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
2323         rthdr->hdr.it_present =
2324                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
2325                             (1 << IEEE80211_RADIOTAP_CHANNEL));
2326
2327         if (rate) {
2328                 rthdr->rate_or_pad = rate->bitrate / 5;
2329                 rthdr->hdr.it_present |=
2330                         cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
2331         }
2332         rthdr->chan_freq = cpu_to_le16(status->freq);
2333
2334         if (status->band == IEEE80211_BAND_5GHZ)
2335                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
2336                                                 IEEE80211_CHAN_5GHZ);
2337         else
2338                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
2339                                                 IEEE80211_CHAN_2GHZ);
2340
2341         skb_set_mac_header(skb, 0);
2342         skb->ip_summed = CHECKSUM_UNNECESSARY;
2343         skb->pkt_type = PACKET_OTHERHOST;
2344         skb->protocol = htons(ETH_P_802_2);
2345
2346         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2347                 if (!ieee80211_sdata_running(sdata))
2348                         continue;
2349
2350                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2351                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2352                         continue;
2353
2354                 if (prev_dev) {
2355                         skb2 = skb_clone(skb, GFP_ATOMIC);
2356                         if (skb2) {
2357                                 skb2->dev = prev_dev;
2358                                 netif_receive_skb(skb2);
2359                         }
2360                 }
2361
2362                 prev_dev = sdata->dev;
2363                 sdata->dev->stats.rx_packets++;
2364                 sdata->dev->stats.rx_bytes += skb->len;
2365         }
2366
2367         if (prev_dev) {
2368                 skb->dev = prev_dev;
2369                 netif_receive_skb(skb);
2370                 return;
2371         }
2372
2373  out_free_skb:
2374         dev_kfree_skb(skb);
2375 }
2376
2377 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
2378                                          ieee80211_rx_result res)
2379 {
2380         switch (res) {
2381         case RX_DROP_MONITOR:
2382                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2383                 if (rx->sta)
2384                         rx->sta->rx_dropped++;
2385                 /* fall through */
2386         case RX_CONTINUE: {
2387                 struct ieee80211_rate *rate = NULL;
2388                 struct ieee80211_supported_band *sband;
2389                 struct ieee80211_rx_status *status;
2390
2391                 status = IEEE80211_SKB_RXCB((rx->skb));
2392
2393                 sband = rx->local->hw.wiphy->bands[status->band];
2394                 if (!(status->flag & RX_FLAG_HT))
2395                         rate = &sband->bitrates[status->rate_idx];
2396
2397                 ieee80211_rx_cooked_monitor(rx, rate);
2398                 break;
2399                 }
2400         case RX_DROP_UNUSABLE:
2401                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2402                 if (rx->sta)
2403                         rx->sta->rx_dropped++;
2404                 dev_kfree_skb(rx->skb);
2405                 break;
2406         case RX_QUEUED:
2407                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
2408                 break;
2409         }
2410 }
2411
2412 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
2413                                   struct sk_buff_head *frames)
2414 {
2415         ieee80211_rx_result res = RX_DROP_MONITOR;
2416         struct sk_buff *skb;
2417
2418 #define CALL_RXH(rxh)                   \
2419         do {                            \
2420                 res = rxh(rx);          \
2421                 if (res != RX_CONTINUE) \
2422                         goto rxh_next;  \
2423         } while (0);
2424
2425         while ((skb = __skb_dequeue(frames))) {
2426                 /*
2427                  * all the other fields are valid across frames
2428                  * that belong to an aMPDU since they are on the
2429                  * same TID from the same station
2430                  */
2431                 rx->skb = skb;
2432                 rx->flags = 0;
2433
2434                 CALL_RXH(ieee80211_rx_h_decrypt)
2435                 CALL_RXH(ieee80211_rx_h_check_more_data)
2436                 CALL_RXH(ieee80211_rx_h_sta_process)
2437                 CALL_RXH(ieee80211_rx_h_defragment)
2438                 CALL_RXH(ieee80211_rx_h_ps_poll)
2439                 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2440                 /* must be after MMIC verify so header is counted in MPDU mic */
2441                 CALL_RXH(ieee80211_rx_h_remove_qos_control)
2442                 CALL_RXH(ieee80211_rx_h_amsdu)
2443 #ifdef CONFIG_MAC80211_MESH
2444                 if (ieee80211_vif_is_mesh(&rx->sdata->vif))
2445                         CALL_RXH(ieee80211_rx_h_mesh_fwding);
2446 #endif
2447                 CALL_RXH(ieee80211_rx_h_data)
2448
2449                 /* special treatment -- needs the queue */
2450                 res = ieee80211_rx_h_ctrl(rx, frames);
2451                 if (res != RX_CONTINUE)
2452                         goto rxh_next;
2453
2454                 CALL_RXH(ieee80211_rx_h_mgmt_check)
2455                 CALL_RXH(ieee80211_rx_h_action)
2456                 CALL_RXH(ieee80211_rx_h_userspace_mgmt)
2457                 CALL_RXH(ieee80211_rx_h_action_return)
2458                 CALL_RXH(ieee80211_rx_h_mgmt)
2459
2460  rxh_next:
2461                 ieee80211_rx_handlers_result(rx, res);
2462
2463 #undef CALL_RXH
2464         }
2465 }
2466
2467 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
2468 {
2469         struct sk_buff_head reorder_release;
2470         ieee80211_rx_result res = RX_DROP_MONITOR;
2471
2472         __skb_queue_head_init(&reorder_release);
2473
2474 #define CALL_RXH(rxh)                   \
2475         do {                            \
2476                 res = rxh(rx);          \
2477                 if (res != RX_CONTINUE) \
2478                         goto rxh_next;  \
2479         } while (0);
2480
2481         CALL_RXH(ieee80211_rx_h_passive_scan)
2482         CALL_RXH(ieee80211_rx_h_check)
2483
2484         ieee80211_rx_reorder_ampdu(rx, &reorder_release);
2485
2486         ieee80211_rx_handlers(rx, &reorder_release);
2487         return;
2488
2489  rxh_next:
2490         ieee80211_rx_handlers_result(rx, res);
2491
2492 #undef CALL_RXH
2493 }
2494
2495 /*
2496  * This function makes calls into the RX path. Therefore the
2497  * caller must hold the sta_info->lock and everything has to
2498  * be under rcu_read_lock protection as well.
2499  */
2500 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
2501 {
2502         struct sk_buff_head frames;
2503         struct ieee80211_rx_data rx = {
2504                 .sta = sta,
2505                 .sdata = sta->sdata,
2506                 .local = sta->local,
2507                 .queue = tid,
2508         };
2509         struct tid_ampdu_rx *tid_agg_rx;
2510
2511         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
2512         if (!tid_agg_rx)
2513                 return;
2514
2515         __skb_queue_head_init(&frames);
2516
2517         spin_lock(&tid_agg_rx->reorder_lock);
2518         ieee80211_sta_reorder_release(&sta->local->hw, tid_agg_rx, &frames);
2519         spin_unlock(&tid_agg_rx->reorder_lock);
2520
2521         ieee80211_rx_handlers(&rx, &frames);
2522 }
2523
2524 /* main receive path */
2525
2526 static int prepare_for_handlers(struct ieee80211_rx_data *rx,
2527                                 struct ieee80211_hdr *hdr)
2528 {
2529         struct ieee80211_sub_if_data *sdata = rx->sdata;
2530         struct sk_buff *skb = rx->skb;
2531         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2532         u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2533         int multicast = is_multicast_ether_addr(hdr->addr1);
2534
2535         switch (sdata->vif.type) {
2536         case NL80211_IFTYPE_STATION:
2537                 if (!bssid && !sdata->u.mgd.use_4addr)
2538                         return 0;
2539                 if (!multicast &&
2540                     compare_ether_addr(sdata->vif.addr, hdr->addr1) != 0) {
2541                         if (!(sdata->dev->flags & IFF_PROMISC))
2542                                 return 0;
2543                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2544                 }
2545                 break;
2546         case NL80211_IFTYPE_ADHOC:
2547                 if (!bssid)
2548                         return 0;
2549                 if (ieee80211_is_beacon(hdr->frame_control)) {
2550                         return 1;
2551                 }
2552                 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2553                         if (!(status->rx_flags & IEEE80211_RX_IN_SCAN))
2554                                 return 0;
2555                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2556                 } else if (!multicast &&
2557                            compare_ether_addr(sdata->vif.addr,
2558                                               hdr->addr1) != 0) {
2559                         if (!(sdata->dev->flags & IFF_PROMISC))
2560                                 return 0;
2561                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2562                 } else if (!rx->sta) {
2563                         int rate_idx;
2564                         if (status->flag & RX_FLAG_HT)
2565                                 rate_idx = 0; /* TODO: HT rates */
2566                         else
2567                                 rate_idx = status->rate_idx;
2568                         rx->sta = ieee80211_ibss_add_sta(sdata, bssid,
2569                                         hdr->addr2, BIT(rate_idx), GFP_ATOMIC);
2570                 }
2571                 break;
2572         case NL80211_IFTYPE_MESH_POINT:
2573                 if (!multicast &&
2574                     compare_ether_addr(sdata->vif.addr,
2575                                        hdr->addr1) != 0) {
2576                         if (!(sdata->dev->flags & IFF_PROMISC))
2577                                 return 0;
2578
2579                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2580                 }
2581                 break;
2582         case NL80211_IFTYPE_AP_VLAN:
2583         case NL80211_IFTYPE_AP:
2584                 if (!bssid) {
2585                         if (compare_ether_addr(sdata->vif.addr,
2586                                                hdr->addr1))
2587                                 return 0;
2588                 } else if (!ieee80211_bssid_match(bssid,
2589                                         sdata->vif.addr)) {
2590                         if (!(status->rx_flags & IEEE80211_RX_IN_SCAN))
2591                                 return 0;
2592                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2593                 }
2594                 break;
2595         case NL80211_IFTYPE_WDS:
2596                 if (bssid || !ieee80211_is_data(hdr->frame_control))
2597                         return 0;
2598                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2599                         return 0;
2600                 break;
2601         default:
2602                 /* should never get here */
2603                 WARN_ON(1);
2604                 break;
2605         }
2606
2607         return 1;
2608 }
2609
2610 /*
2611  * This function returns whether or not the SKB
2612  * was destined for RX processing or not, which,
2613  * if consume is true, is equivalent to whether
2614  * or not the skb was consumed.
2615  */
2616 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
2617                                             struct sk_buff *skb, bool consume)
2618 {
2619         struct ieee80211_local *local = rx->local;
2620         struct ieee80211_sub_if_data *sdata = rx->sdata;
2621         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2622         struct ieee80211_hdr *hdr = (void *)skb->data;
2623         int prepares;
2624
2625         rx->skb = skb;
2626         status->rx_flags |= IEEE80211_RX_RA_MATCH;
2627         prepares = prepare_for_handlers(rx, hdr);
2628
2629         if (!prepares)
2630                 return false;
2631
2632         if (status->flag & RX_FLAG_MMIC_ERROR) {
2633                 if (status->rx_flags & IEEE80211_RX_RA_MATCH)
2634                         ieee80211_rx_michael_mic_report(hdr, rx);
2635                 return false;
2636         }
2637
2638         if (!consume) {
2639                 skb = skb_copy(skb, GFP_ATOMIC);
2640                 if (!skb) {
2641                         if (net_ratelimit())
2642                                 wiphy_debug(local->hw.wiphy,
2643                                         "failed to copy multicast frame for %s\n",
2644                                         sdata->name);
2645                         return true;
2646                 }
2647
2648                 rx->skb = skb;
2649         }
2650
2651         ieee80211_invoke_rx_handlers(rx);
2652         return true;
2653 }
2654
2655 /*
2656  * This is the actual Rx frames handler. as it blongs to Rx path it must
2657  * be called with rcu_read_lock protection.
2658  */
2659 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2660                                          struct sk_buff *skb)
2661 {
2662         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2663         struct ieee80211_local *local = hw_to_local(hw);
2664         struct ieee80211_sub_if_data *sdata;
2665         struct ieee80211_hdr *hdr;
2666         __le16 fc;
2667         struct ieee80211_rx_data rx;
2668         struct ieee80211_sub_if_data *prev;
2669         struct sta_info *sta, *tmp, *prev_sta;
2670         int err = 0;
2671
2672         fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
2673         memset(&rx, 0, sizeof(rx));
2674         rx.skb = skb;
2675         rx.local = local;
2676
2677         if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
2678                 local->dot11ReceivedFragmentCount++;
2679
2680         if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) ||
2681                      test_bit(SCAN_OFF_CHANNEL, &local->scanning)))
2682                 status->rx_flags |= IEEE80211_RX_IN_SCAN;
2683
2684         if (ieee80211_is_mgmt(fc))
2685                 err = skb_linearize(skb);
2686         else
2687                 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
2688
2689         if (err) {
2690                 dev_kfree_skb(skb);
2691                 return;
2692         }
2693
2694         hdr = (struct ieee80211_hdr *)skb->data;
2695         ieee80211_parse_qos(&rx);
2696         ieee80211_verify_alignment(&rx);
2697
2698         if (ieee80211_is_data(fc)) {
2699                 prev_sta = NULL;
2700
2701                 for_each_sta_info(local, hdr->addr2, sta, tmp) {
2702                         if (!prev_sta) {
2703                                 prev_sta = sta;
2704                                 continue;
2705                         }
2706
2707                         rx.sta = prev_sta;
2708                         rx.sdata = prev_sta->sdata;
2709                         ieee80211_prepare_and_rx_handle(&rx, skb, false);
2710
2711                         prev_sta = sta;
2712                 }
2713
2714                 if (prev_sta) {
2715                         rx.sta = prev_sta;
2716                         rx.sdata = prev_sta->sdata;
2717
2718                         if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
2719                                 return;
2720                 }
2721         }
2722
2723         prev = NULL;
2724
2725         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2726                 if (!ieee80211_sdata_running(sdata))
2727                         continue;
2728
2729                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
2730                     sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2731                         continue;
2732
2733                 /*
2734                  * frame is destined for this interface, but if it's
2735                  * not also for the previous one we handle that after
2736                  * the loop to avoid copying the SKB once too much
2737                  */
2738
2739                 if (!prev) {
2740                         prev = sdata;
2741                         continue;
2742                 }
2743
2744                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
2745                 rx.sdata = prev;
2746                 ieee80211_prepare_and_rx_handle(&rx, skb, false);
2747
2748                 prev = sdata;
2749         }
2750
2751         if (prev) {
2752                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
2753                 rx.sdata = prev;
2754
2755                 if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
2756                         return;
2757         }
2758
2759         dev_kfree_skb(skb);
2760 }
2761
2762 /*
2763  * This is the receive path handler. It is called by a low level driver when an
2764  * 802.11 MPDU is received from the hardware.
2765  */
2766 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
2767 {
2768         struct ieee80211_local *local = hw_to_local(hw);
2769         struct ieee80211_rate *rate = NULL;
2770         struct ieee80211_supported_band *sband;
2771         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2772
2773         WARN_ON_ONCE(softirq_count() == 0);
2774
2775         if (WARN_ON(status->band < 0 ||
2776                     status->band >= IEEE80211_NUM_BANDS))
2777                 goto drop;
2778
2779         sband = local->hw.wiphy->bands[status->band];
2780         if (WARN_ON(!sband))
2781                 goto drop;
2782
2783         /*
2784          * If we're suspending, it is possible although not too likely
2785          * that we'd be receiving frames after having already partially
2786          * quiesced the stack. We can't process such frames then since
2787          * that might, for example, cause stations to be added or other
2788          * driver callbacks be invoked.
2789          */
2790         if (unlikely(local->quiescing || local->suspended))
2791                 goto drop;
2792
2793         /*
2794          * The same happens when we're not even started,
2795          * but that's worth a warning.
2796          */
2797         if (WARN_ON(!local->started))
2798                 goto drop;
2799
2800         if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
2801                 /*
2802                  * Validate the rate, unless a PLCP error means that
2803                  * we probably can't have a valid rate here anyway.
2804                  */
2805
2806                 if (status->flag & RX_FLAG_HT) {
2807                         /*
2808                          * rate_idx is MCS index, which can be [0-76]
2809                          * as documented on:
2810                          *
2811                          * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
2812                          *
2813                          * Anything else would be some sort of driver or
2814                          * hardware error. The driver should catch hardware
2815                          * errors.
2816                          */
2817                         if (WARN((status->rate_idx < 0 ||
2818                                  status->rate_idx > 76),
2819                                  "Rate marked as an HT rate but passed "
2820                                  "status->rate_idx is not "
2821                                  "an MCS index [0-76]: %d (0x%02x)\n",
2822                                  status->rate_idx,
2823                                  status->rate_idx))
2824                                 goto drop;
2825                 } else {
2826                         if (WARN_ON(status->rate_idx < 0 ||
2827                                     status->rate_idx >= sband->n_bitrates))
2828                                 goto drop;
2829                         rate = &sband->bitrates[status->rate_idx];
2830                 }
2831         }
2832
2833         status->rx_flags = 0;
2834
2835         /*
2836          * key references and virtual interfaces are protected using RCU
2837          * and this requires that we are in a read-side RCU section during
2838          * receive processing
2839          */
2840         rcu_read_lock();
2841
2842         /*
2843          * Frames with failed FCS/PLCP checksum are not returned,
2844          * all other frames are returned without radiotap header
2845          * if it was previously present.
2846          * Also, frames with less than 16 bytes are dropped.
2847          */
2848         skb = ieee80211_rx_monitor(local, skb, rate);
2849         if (!skb) {
2850                 rcu_read_unlock();
2851                 return;
2852         }
2853
2854         __ieee80211_rx_handle_packet(hw, skb);
2855
2856         rcu_read_unlock();
2857
2858         return;
2859  drop:
2860         kfree_skb(skb);
2861 }
2862 EXPORT_SYMBOL(ieee80211_rx);
2863
2864 /* This is a version of the rx handler that can be called from hard irq
2865  * context. Post the skb on the queue and schedule the tasklet */
2866 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
2867 {
2868         struct ieee80211_local *local = hw_to_local(hw);
2869
2870         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2871
2872         skb->pkt_type = IEEE80211_RX_MSG;
2873         skb_queue_tail(&local->skb_queue, skb);
2874         tasklet_schedule(&local->tasklet);
2875 }
2876 EXPORT_SYMBOL(ieee80211_rx_irqsafe);