git.oblomov.eu Git - linux-2.6/blob - 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       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/kernel.h>
  14 #include <linux/skbuff.h>
  15 #include <linux/netdevice.h>
  16 #include <linux/etherdevice.h>
  17 #include <linux/rcupdate.h>
  18 #include <net/mac80211.h>
  19 #include <net/ieee80211_radiotap.h>
  20
  21 #include "ieee80211_i.h"
  22 #include "driver-ops.h"
  23 #include "led.h"
  24 #include "mesh.h"
  25 #include "wep.h"
  26 #include "wpa.h"
  27 #include "tkip.h"
  28 #include "wme.h"
  29
  30 static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
  31                                            struct tid_ampdu_rx *tid_agg_rx,
  32                                            struct sk_buff *skb,
  33                                            struct ieee80211_rx_status *status,
  34                                            u16 mpdu_seq_num,
  35                                            int bar_req);
  36 /*
  37  * monitor mode reception
  38  *
  39  * This function cleans up the SKB, i.e. it removes all the stuff
  40  * only useful for monitoring.
  41  */
  42 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
  43                                            struct sk_buff *skb,
  44                                            int rtap_len)
  45 {
  46         skb_pull(skb, rtap_len);
  47
  48         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
  49                 if (likely(skb->len > FCS_LEN))
  50                         skb_trim(skb, skb->len - FCS_LEN);
  51                 else {
  52                         /* driver bug */
  53                         WARN_ON(1);
  54                         dev_kfree_skb(skb);
  55                         skb = NULL;
  56                 }
  57         }
  58
  59         return skb;
  60 }
  61
  62 static inline int should_drop_frame(struct ieee80211_rx_status *status,
  63                                     struct sk_buff *skb,
  64                                     int present_fcs_len,
  65                                     int radiotap_len)
  66 {
  67         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  68
  69         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
  70                 return 1;
  71         if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len))
  72                 return 1;
  73         if (ieee80211_is_ctl(hdr->frame_control) &&
  74             !ieee80211_is_pspoll(hdr->frame_control) &&
  75             !ieee80211_is_back_req(hdr->frame_control))
  76                 return 1;
  77         return 0;
  78 }
  79
  80 static int
  81 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
  82                           struct ieee80211_rx_status *status)
  83 {
  84         int len;
  85
  86         /* always present fields */
  87         len = sizeof(struct ieee80211_radiotap_header) + 9;
  88
  89         if (status->flag & RX_FLAG_TSFT)
  90                 len += 8;
  91         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
  92                 len += 1;
  93         if (local->hw.flags & IEEE80211_HW_NOISE_DBM)
  94                 len += 1;
  95
  96         if (len & 1) /* padding for RX_FLAGS if necessary */
  97                 len++;
  98
  99         /* make sure radiotap starts at a naturally aligned address */
 100         if (len % 8)
 101                 len = roundup(len, 8);
 102
 103         return len;
 104 }
 105
 106 /*
 107  * ieee80211_add_rx_radiotap_header - add radiotap header
 108  *
 109  * add a radiotap header containing all the fields which the hardware provided.
 110  */
 111 static void
 112 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
 113                                  struct sk_buff *skb,
 114                                  struct ieee80211_rx_status *status,
 115                                  struct ieee80211_rate *rate,
 116                                  int rtap_len)
 117 {
 118         struct ieee80211_radiotap_header *rthdr;
 119         unsigned char *pos;
 120
 121         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
 122         memset(rthdr, 0, rtap_len);
 123
 124         /* radiotap header, set always present flags */
 125         rthdr->it_present =
 126                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 127                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
 128                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
 129                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
 130         rthdr->it_len = cpu_to_le16(rtap_len);
 131
 132         pos = (unsigned char *)(rthdr+1);
 133
 134         /* the order of the following fields is important */
 135
 136         /* IEEE80211_RADIOTAP_TSFT */
 137         if (status->flag & RX_FLAG_TSFT) {
 138                 *(__le64 *)pos = cpu_to_le64(status->mactime);
 139                 rthdr->it_present |=
 140                         cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
 141                 pos += 8;
 142         }
 143
 144         /* IEEE80211_RADIOTAP_FLAGS */
 145         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 146                 *pos |= IEEE80211_RADIOTAP_F_FCS;
 147         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 148                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
 149         if (status->flag & RX_FLAG_SHORTPRE)
 150                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
 151         pos++;
 152
 153         /* IEEE80211_RADIOTAP_RATE */
 154         if (status->flag & RX_FLAG_HT) {
 155                 /*
 156                  * TODO: add following information into radiotap header once
 157                  * suitable fields are defined for it:
 158                  * - MCS index (status->rate_idx)
 159                  * - HT40 (status->flag & RX_FLAG_40MHZ)
 160                  * - short-GI (status->flag & RX_FLAG_SHORT_GI)
 161                  */
 162                 *pos = 0;
 163         } else {
 164                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
 165                 *pos = rate->bitrate / 5;
 166         }
 167         pos++;
 168
 169         /* IEEE80211_RADIOTAP_CHANNEL */
 170         *(__le16 *)pos = cpu_to_le16(status->freq);
 171         pos += 2;
 172         if (status->band == IEEE80211_BAND_5GHZ)
 173                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
 174                                              IEEE80211_CHAN_5GHZ);
 175         else if (rate->flags & IEEE80211_RATE_ERP_G)
 176                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
 177                                              IEEE80211_CHAN_2GHZ);
 178         else
 179                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_CCK |
 180                                              IEEE80211_CHAN_2GHZ);
 181         pos += 2;
 182
 183         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
 184         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
 185                 *pos = status->signal;
 186                 rthdr->it_present |=
 187                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
 188                 pos++;
 189         }
 190
 191         /* IEEE80211_RADIOTAP_DBM_ANTNOISE */
 192         if (local->hw.flags & IEEE80211_HW_NOISE_DBM) {
 193                 *pos = status->noise;
 194                 rthdr->it_present |=
 195                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE);
 196                 pos++;
 197         }
 198
 199         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
 200
 201         /* IEEE80211_RADIOTAP_ANTENNA */
 202         *pos = status->antenna;
 203         pos++;
 204
 205         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
 206
 207         /* IEEE80211_RADIOTAP_RX_FLAGS */
 208         /* ensure 2 byte alignment for the 2 byte field as required */
 209         if ((pos - (unsigned char *)rthdr) & 1)
 210                 pos++;
 211         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
 212                 *(__le16 *)pos |= cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADPLCP);
 213         pos += 2;
 214 }
 215
 216 /*
 217  * This function copies a received frame to all monitor interfaces and
 218  * returns a cleaned-up SKB that no longer includes the FCS nor the
 219  * radiotap header the driver might have added.
 220  */
 221 static struct sk_buff *
 222 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
 223                      struct ieee80211_rx_status *status,
 224                      struct ieee80211_rate *rate)
 225 {
 226         struct ieee80211_sub_if_data *sdata;
 227         int needed_headroom = 0;
 228         struct sk_buff *skb, *skb2;
 229         struct net_device *prev_dev = NULL;
 230         int present_fcs_len = 0;
 231         int rtap_len = 0;
 232
 233         /*
 234          * First, we may need to make a copy of the skb because
 235          *  (1) we need to modify it for radiotap (if not present), and
 236          *  (2) the other RX handlers will modify the skb we got.
 237          *
 238          * We don't need to, of course, if we aren't going to return
 239          * the SKB because it has a bad FCS/PLCP checksum.
 240          */
 241         if (status->flag & RX_FLAG_RADIOTAP)
 242                 rtap_len = ieee80211_get_radiotap_len(origskb->data);
 243         else
 244                 /* room for the radiotap header based on driver features */
 245                 needed_headroom = ieee80211_rx_radiotap_len(local, status);
 246
 247         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 248                 present_fcs_len = FCS_LEN;
 249
 250         if (!local->monitors) {
 251                 if (should_drop_frame(status, origskb, present_fcs_len,
 252                                       rtap_len)) {
 253                         dev_kfree_skb(origskb);
 254                         return NULL;
 255                 }
 256
 257                 return remove_monitor_info(local, origskb, rtap_len);
 258         }
 259
 260         if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) {
 261                 /* only need to expand headroom if necessary */
 262                 skb = origskb;
 263                 origskb = NULL;
 264
 265                 /*
 266                  * This shouldn't trigger often because most devices have an
 267                  * RX header they pull before we get here, and that should
 268                  * be big enough for our radiotap information. We should
 269                  * probably export the length to drivers so that we can have
 270                  * them allocate enough headroom to start with.
 271                  */
 272                 if (skb_headroom(skb) < needed_headroom &&
 273                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
 274                         dev_kfree_skb(skb);
 275                         return NULL;
 276                 }
 277         } else {
 278                 /*
 279                  * Need to make a copy and possibly remove radiotap header
 280                  * and FCS from the original.
 281                  */
 282                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
 283
 284                 origskb = remove_monitor_info(local, origskb, rtap_len);
 285
 286                 if (!skb)
 287                         return origskb;
 288         }
 289
 290         /* if necessary, prepend radiotap information */
 291         if (!(status->flag & RX_FLAG_RADIOTAP))
 292                 ieee80211_add_rx_radiotap_header(local, skb, status, rate,
 293                                                  needed_headroom);
 294
 295         skb_reset_mac_header(skb);
 296         skb->ip_summed = CHECKSUM_UNNECESSARY;
 297         skb->pkt_type = PACKET_OTHERHOST;
 298         skb->protocol = htons(ETH_P_802_2);
 299
 300         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 301                 if (!netif_running(sdata->dev))
 302                         continue;
 303
 304                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
 305                         continue;
 306
 307                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
 308                         continue;
 309
 310                 if (prev_dev) {
 311                         skb2 = skb_clone(skb, GFP_ATOMIC);
 312                         if (skb2) {
 313                                 skb2->dev = prev_dev;
 314                                 netif_rx(skb2);
 315                         }
 316                 }
 317
 318                 prev_dev = sdata->dev;
 319                 sdata->dev->stats.rx_packets++;
 320                 sdata->dev->stats.rx_bytes += skb->len;
 321         }
 322
 323         if (prev_dev) {
 324                 skb->dev = prev_dev;
 325                 netif_rx(skb);
 326         } else
 327                 dev_kfree_skb(skb);
 328
 329         return origskb;
 330 }
 331
 332
 333 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
 334 {
 335         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 336         int tid;
 337
 338         /* does the frame have a qos control field? */
 339         if (ieee80211_is_data_qos(hdr->frame_control)) {
 340                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 341                 /* frame has qos control */
 342                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
 343                 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
 344                         rx->flags |= IEEE80211_RX_AMSDU;
 345                 else
 346                         rx->flags &= ~IEEE80211_RX_AMSDU;
 347         } else {
 348                 /*
 349                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
 350                  *
 351                  *      Sequence numbers for management frames, QoS data
 352                  *      frames with a broadcast/multicast address in the
 353                  *      Address 1 field, and all non-QoS data frames sent
 354                  *      by QoS STAs are assigned using an additional single
 355                  *      modulo-4096 counter, [...]
 356                  *
 357                  * We also use that counter for non-QoS STAs.
 358                  */
 359                 tid = NUM_RX_DATA_QUEUES - 1;
 360         }
 361
 362         rx->queue = tid;
 363         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 364          * For now, set skb->priority to 0 for other cases. */
 365         rx->skb->priority = (tid > 7) ? 0 : tid;
 366 }
 367
 368 /**
 369  * DOC: Packet alignment
 370  *
 371  * Drivers always need to pass packets that are aligned to two-byte boundaries
 372  * to the stack.
 373  *
 374  * Additionally, should, if possible, align the payload data in a way that
 375  * guarantees that the contained IP header is aligned to a four-byte
 376  * boundary. In the case of regular frames, this simply means aligning the
 377  * payload to a four-byte boundary (because either the IP header is directly
 378  * contained, or IV/RFC1042 headers that have a length divisible by four are
 379  * in front of it).
 380  *
 381  * With A-MSDU frames, however, the payload data address must yield two modulo
 382  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
 383  * push the IP header further back to a multiple of four again. Thankfully, the
 384  * specs were sane enough this time around to require padding each A-MSDU
 385  * subframe to a length that is a multiple of four.
 386  *
 387  * Padding like Atheros hardware adds which is inbetween the 802.11 header and
 388  * the payload is not supported, the driver is required to move the 802.11
 389  * header to be directly in front of the payload in that case.
 390  */
 391 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
 392 {
 393         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 394         int hdrlen;
 395
 396 #ifndef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
 397         return;
 398 #endif
 399
 400         if (WARN_ONCE((unsigned long)rx->skb->data & 1,
 401                       "unaligned packet at 0x%p\n", rx->skb->data))
 402                 return;
 403
 404         if (!ieee80211_is_data_present(hdr->frame_control))
 405                 return;
 406
 407         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 408         if (rx->flags & IEEE80211_RX_AMSDU)
 409                 hdrlen += ETH_HLEN;
 410         WARN_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3,
 411                   "unaligned IP payload at 0x%p\n", rx->skb->data + hdrlen);
 412 }
 413
 414
 415 /* rx handlers */
 416
 417 static ieee80211_rx_result debug_noinline
 418 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
 419 {
 420         struct ieee80211_local *local = rx->local;
 421         struct sk_buff *skb = rx->skb;
 422
 423         if (unlikely(local->hw_scanning))
 424                 return ieee80211_scan_rx(rx->sdata, skb, rx->status);
 425
 426         if (unlikely(local->sw_scanning)) {
 427                 /* drop all the other packets during a software scan anyway */
 428                 if (ieee80211_scan_rx(rx->sdata, skb, rx->status)
 429                     != RX_QUEUED)
 430                         dev_kfree_skb(skb);
 431                 return RX_QUEUED;
 432         }
 433
 434         if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
 435                 /* scanning finished during invoking of handlers */
 436                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
 437                 return RX_DROP_UNUSABLE;
 438         }
 439
 440         return RX_CONTINUE;
 441 }
 442
 443
 444 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
 445 {
 446         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 447
 448         if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
 449                 return 0;
 450
 451         return ieee80211_is_robust_mgmt_frame(hdr);
 452 }
 453
 454
 455 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
 456 {
 457         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 458
 459         if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
 460                 return 0;
 461
 462         return ieee80211_is_robust_mgmt_frame(hdr);
 463 }
 464
 465
 466 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
 467 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
 468 {
 469         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
 470         struct ieee80211_mmie *mmie;
 471
 472         if (skb->len < 24 + sizeof(*mmie) ||
 473             !is_multicast_ether_addr(hdr->da))
 474                 return -1;
 475
 476         if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
 477                 return -1; /* not a robust management frame */
 478
 479         mmie = (struct ieee80211_mmie *)
 480                 (skb->data + skb->len - sizeof(*mmie));
 481         if (mmie->element_id != WLAN_EID_MMIE ||
 482             mmie->length != sizeof(*mmie) - 2)
 483                 return -1;
 484
 485         return le16_to_cpu(mmie->key_id);
 486 }
 487
 488
 489 static ieee80211_rx_result
 490 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
 491 {
 492         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 493         unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
 494
 495         if (ieee80211_is_data(hdr->frame_control)) {
 496                 if (!ieee80211_has_a4(hdr->frame_control))
 497                         return RX_DROP_MONITOR;
 498                 if (memcmp(hdr->addr4, rx->dev->dev_addr, ETH_ALEN) == 0)
 499                         return RX_DROP_MONITOR;
 500         }
 501
 502         /* If there is not an established peer link and this is not a peer link
 503          * establisment frame, beacon or probe, drop the frame.
 504          */
 505
 506         if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
 507                 struct ieee80211_mgmt *mgmt;
 508
 509                 if (!ieee80211_is_mgmt(hdr->frame_control))
 510                         return RX_DROP_MONITOR;
 511
 512                 if (ieee80211_is_action(hdr->frame_control)) {
 513                         mgmt = (struct ieee80211_mgmt *)hdr;
 514                         if (mgmt->u.action.category != PLINK_CATEGORY)
 515                                 return RX_DROP_MONITOR;
 516                         return RX_CONTINUE;
 517                 }
 518
 519                 if (ieee80211_is_probe_req(hdr->frame_control) ||
 520                     ieee80211_is_probe_resp(hdr->frame_control) ||
 521                     ieee80211_is_beacon(hdr->frame_control))
 522                         return RX_CONTINUE;
 523
 524                 return RX_DROP_MONITOR;
 525
 526         }
 527
 528 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
 529
 530         if (ieee80211_is_data(hdr->frame_control) &&
 531             is_multicast_ether_addr(hdr->addr1) &&
 532             mesh_rmc_check(hdr->addr4, msh_h_get(hdr, hdrlen), rx->sdata))
 533                 return RX_DROP_MONITOR;
 534 #undef msh_h_get
 535
 536         return RX_CONTINUE;
 537 }
 538
 539
 540 static ieee80211_rx_result debug_noinline
 541 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
 542 {
 543         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 544
 545         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 546         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 547                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
 548                              rx->sta->last_seq_ctrl[rx->queue] ==
 549                              hdr->seq_ctrl)) {
 550                         if (rx->flags & IEEE80211_RX_RA_MATCH) {
 551                                 rx->local->dot11FrameDuplicateCount++;
 552                                 rx->sta->num_duplicates++;
 553                         }
 554                         return RX_DROP_MONITOR;
 555                 } else
 556                         rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
 557         }
 558
 559         if (unlikely(rx->skb->len < 16)) {
 560                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 561                 return RX_DROP_MONITOR;
 562         }
 563
 564         /* Drop disallowed frame classes based on STA auth/assoc state;
 565          * IEEE 802.11, Chap 5.5.
 566          *
 567          * mac80211 filters only based on association state, i.e. it drops
 568          * Class 3 frames from not associated stations. hostapd sends
 569          * deauth/disassoc frames when needed. In addition, hostapd is
 570          * responsible for filtering on both auth and assoc states.
 571          */
 572
 573         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
 574                 return ieee80211_rx_mesh_check(rx);
 575
 576         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
 577                       ieee80211_is_pspoll(hdr->frame_control)) &&
 578                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
 579                      (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
 580                 if ((!ieee80211_has_fromds(hdr->frame_control) &&
 581                      !ieee80211_has_tods(hdr->frame_control) &&
 582                      ieee80211_is_data(hdr->frame_control)) ||
 583                     !(rx->flags & IEEE80211_RX_RA_MATCH)) {
 584                         /* Drop IBSS frames and frames for other hosts
 585                          * silently. */
 586                         return RX_DROP_MONITOR;
 587                 }
 588
 589                 return RX_DROP_MONITOR;
 590         }
 591
 592         return RX_CONTINUE;
 593 }
 594
 595
 596 static ieee80211_rx_result debug_noinline
 597 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
 598 {
 599         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 600         int keyidx;
 601         int hdrlen;
 602         ieee80211_rx_result result = RX_DROP_UNUSABLE;
 603         struct ieee80211_key *stakey = NULL;
 604         int mmie_keyidx = -1;
 605
 606         /*
 607          * Key selection 101
 608          *
 609          * There are four types of keys:
 610          *  - GTK (group keys)
 611          *  - IGTK (group keys for management frames)
 612          *  - PTK (pairwise keys)
 613          *  - STK (station-to-station pairwise keys)
 614          *
 615          * When selecting a key, we have to distinguish between multicast
 616          * (including broadcast) and unicast frames, the latter can only
 617          * use PTKs and STKs while the former always use GTKs and IGTKs.
 618          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
 619          * unicast frames can also use key indices like GTKs. Hence, if we
 620          * don't have a PTK/STK we check the key index for a WEP key.
 621          *
 622          * Note that in a regular BSS, multicast frames are sent by the
 623          * AP only, associated stations unicast the frame to the AP first
 624          * which then multicasts it on their behalf.
 625          *
 626          * There is also a slight problem in IBSS mode: GTKs are negotiated
 627          * with each station, that is something we don't currently handle.
 628          * The spec seems to expect that one negotiates the same key with
 629          * every station but there's no such requirement; VLANs could be
 630          * possible.
 631          */
 632
 633         /*
 634          * No point in finding a key and decrypting if the frame is neither
 635          * addressed to us nor a multicast frame.
 636          */
 637         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
 638                 return RX_CONTINUE;
 639
 640         if (rx->sta)
 641                 stakey = rcu_dereference(rx->sta->key);
 642
 643         if (!ieee80211_has_protected(hdr->frame_control))
 644                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
 645
 646         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
 647                 rx->key = stakey;
 648                 /* Skip decryption if the frame is not protected. */
 649                 if (!ieee80211_has_protected(hdr->frame_control))
 650                         return RX_CONTINUE;
 651         } else if (mmie_keyidx >= 0) {
 652                 /* Broadcast/multicast robust management frame / BIP */
 653                 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
 654                     (rx->status->flag & RX_FLAG_IV_STRIPPED))
 655                         return RX_CONTINUE;
 656
 657                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
 658                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
 659                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
 660                 rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
 661         } else if (!ieee80211_has_protected(hdr->frame_control)) {
 662                 /*
 663                  * The frame was not protected, so skip decryption. However, we
 664                  * need to set rx->key if there is a key that could have been
 665                  * used so that the frame may be dropped if encryption would
 666                  * have been expected.
 667                  */
 668                 struct ieee80211_key *key = NULL;
 669                 if (ieee80211_is_mgmt(hdr->frame_control) &&
 670                     is_multicast_ether_addr(hdr->addr1) &&
 671                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
 672                         rx->key = key;
 673                 else if ((key = rcu_dereference(rx->sdata->default_key)))
 674                         rx->key = key;
 675                 return RX_CONTINUE;
 676         } else {
 677                 /*
 678                  * The device doesn't give us the IV so we won't be
 679                  * able to look up the key. That's ok though, we
 680                  * don't need to decrypt the frame, we just won't
 681                  * be able to keep statistics accurate.
 682                  * Except for key threshold notifications, should
 683                  * we somehow allow the driver to tell us which key
 684                  * the hardware used if this flag is set?
 685                  */
 686                 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
 687                     (rx->status->flag & RX_FLAG_IV_STRIPPED))
 688                         return RX_CONTINUE;
 689
 690                 hdrlen = ieee80211_hdrlen(hdr->frame_control);
 691
 692                 if (rx->skb->len < 8 + hdrlen)
 693                         return RX_DROP_UNUSABLE; /* TODO: count this? */
 694
 695                 /*
 696                  * no need to call ieee80211_wep_get_keyidx,
 697                  * it verifies a bunch of things we've done already
 698                  */
 699                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
 700
 701                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
 702
 703                 /*
 704                  * RSNA-protected unicast frames should always be sent with
 705                  * pairwise or station-to-station keys, but for WEP we allow
 706                  * using a key index as well.
 707                  */
 708                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
 709                     !is_multicast_ether_addr(hdr->addr1))
 710                         rx->key = NULL;
 711         }
 712
 713         if (rx->key) {
 714                 rx->key->tx_rx_count++;
 715                 /* TODO: add threshold stuff again */
 716         } else {
 717                 return RX_DROP_MONITOR;
 718         }
 719
 720         /* Check for weak IVs if possible */
 721         if (rx->sta && rx->key->conf.alg == ALG_WEP &&
 722             ieee80211_is_data(hdr->frame_control) &&
 723             (!(rx->status->flag & RX_FLAG_IV_STRIPPED) ||
 724              !(rx->status->flag & RX_FLAG_DECRYPTED)) &&
 725             ieee80211_wep_is_weak_iv(rx->skb, rx->key))
 726                 rx->sta->wep_weak_iv_count++;
 727
 728         switch (rx->key->conf.alg) {
 729         case ALG_WEP:
 730                 result = ieee80211_crypto_wep_decrypt(rx);
 731                 break;
 732         case ALG_TKIP:
 733                 result = ieee80211_crypto_tkip_decrypt(rx);
 734                 break;
 735         case ALG_CCMP:
 736                 result = ieee80211_crypto_ccmp_decrypt(rx);
 737                 break;
 738         case ALG_AES_CMAC:
 739                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
 740                 break;
 741         }
 742
 743         /* either the frame has been decrypted or will be dropped */
 744         rx->status->flag |= RX_FLAG_DECRYPTED;
 745
 746         return result;
 747 }
 748
 749 static ieee80211_rx_result debug_noinline
 750 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
 751 {
 752         struct ieee80211_local *local;
 753         struct ieee80211_hdr *hdr;
 754         struct sk_buff *skb;
 755
 756         local = rx->local;
 757         skb = rx->skb;
 758         hdr = (struct ieee80211_hdr *) skb->data;
 759
 760         if (!local->pspolling)
 761                 return RX_CONTINUE;
 762
 763         if (!ieee80211_has_fromds(hdr->frame_control))
 764                 /* this is not from AP */
 765                 return RX_CONTINUE;
 766
 767         if (!ieee80211_is_data(hdr->frame_control))
 768                 return RX_CONTINUE;
 769
 770         if (!ieee80211_has_moredata(hdr->frame_control)) {
 771                 /* AP has no more frames buffered for us */
 772                 local->pspolling = false;
 773                 return RX_CONTINUE;
 774         }
 775
 776         /* more data bit is set, let's request a new frame from the AP */
 777         ieee80211_send_pspoll(local, rx->sdata);
 778
 779         return RX_CONTINUE;
 780 }
 781
 782 static void ap_sta_ps_start(struct sta_info *sta)
 783 {
 784         struct ieee80211_sub_if_data *sdata = sta->sdata;
 785         struct ieee80211_local *local = sdata->local;
 786
 787         atomic_inc(&sdata->bss->num_sta_ps);
 788         set_and_clear_sta_flags(sta, WLAN_STA_PS, WLAN_STA_PSPOLL);
 789         drv_sta_notify(local, &sdata->vif, STA_NOTIFY_SLEEP, &sta->sta);
 790 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 791         printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
 792                sdata->dev->name, sta->sta.addr, sta->sta.aid);
 793 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 794 }
 795
 796 static int ap_sta_ps_end(struct sta_info *sta)
 797 {
 798         struct ieee80211_sub_if_data *sdata = sta->sdata;
 799         struct ieee80211_local *local = sdata->local;
 800         struct sk_buff *skb;
 801         int sent = 0;
 802
 803         atomic_dec(&sdata->bss->num_sta_ps);
 804
 805         clear_sta_flags(sta, WLAN_STA_PS | WLAN_STA_PSPOLL);
 806         drv_sta_notify(local, &sdata->vif, STA_NOTIFY_AWAKE, &sta->sta);
 807
 808         if (!skb_queue_empty(&sta->ps_tx_buf))
 809                 sta_info_clear_tim_bit(sta);
 810
 811 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 812         printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
 813                sdata->dev->name, sta->sta.addr, sta->sta.aid);
 814 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 815
 816         /* Send all buffered frames to the station */
 817         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
 818                 sent++;
 819                 skb->requeue = 1;
 820                 dev_queue_xmit(skb);
 821         }
 822         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
 823                 local->total_ps_buffered--;
 824                 sent++;
 825 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 826                 printk(KERN_DEBUG "%s: STA %pM aid %d send PS frame "
 827                        "since STA not sleeping anymore\n", sdata->dev->name,
 828                        sta->sta.addr, sta->sta.aid);
 829 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 830                 skb->requeue = 1;
 831                 dev_queue_xmit(skb);
 832         }
 833
 834         return sent;
 835 }
 836
 837 static ieee80211_rx_result debug_noinline
 838 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
 839 {
 840         struct sta_info *sta = rx->sta;
 841         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 842
 843         if (!sta)
 844                 return RX_CONTINUE;
 845
 846         /* Update last_rx only for IBSS packets which are for the current
 847          * BSSID to avoid keeping the current IBSS network alive in cases where
 848          * other STAs are using different BSSID. */
 849         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
 850                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
 851                                                 NL80211_IFTYPE_ADHOC);
 852                 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0)
 853                         sta->last_rx = jiffies;
 854         } else
 855         if (!is_multicast_ether_addr(hdr->addr1) ||
 856             rx->sdata->vif.type == NL80211_IFTYPE_STATION) {
 857                 /* Update last_rx only for unicast frames in order to prevent
 858                  * the Probe Request frames (the only broadcast frames from a
 859                  * STA in infrastructure mode) from keeping a connection alive.
 860                  * Mesh beacons will update last_rx when if they are found to
 861                  * match the current local configuration when processed.
 862                  */
 863                 if (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
 864                     ieee80211_is_beacon(hdr->frame_control)) {
 865                         rx->sdata->u.mgd.last_beacon = jiffies;
 866                 } else
 867                         sta->last_rx = jiffies;
 868         }
 869
 870         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
 871                 return RX_CONTINUE;
 872
 873         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
 874                 ieee80211_sta_rx_notify(rx->sdata, hdr);
 875
 876         sta->rx_fragments++;
 877         sta->rx_bytes += rx->skb->len;
 878         sta->last_signal = rx->status->signal;
 879         sta->last_qual = rx->status->qual;
 880         sta->last_noise = rx->status->noise;
 881
 882         /*
 883          * Change STA power saving mode only at the end of a frame
 884          * exchange sequence.
 885          */
 886         if (!ieee80211_has_morefrags(hdr->frame_control) &&
 887             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
 888              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
 889                 if (test_sta_flags(sta, WLAN_STA_PS)) {
 890                         /*
 891                          * Ignore doze->wake transitions that are
 892                          * indicated by non-data frames, the standard
 893                          * is unclear here, but for example going to
 894                          * PS mode and then scanning would cause a
 895                          * doze->wake transition for the probe request,
 896                          * and that is clearly undesirable.
 897                          */
 898                         if (ieee80211_is_data(hdr->frame_control) &&
 899                             !ieee80211_has_pm(hdr->frame_control))
 900                                 rx->sent_ps_buffered += ap_sta_ps_end(sta);
 901                 } else {
 902                         if (ieee80211_has_pm(hdr->frame_control))
 903                                 ap_sta_ps_start(sta);
 904                 }
 905         }
 906
 907         /* Drop data::nullfunc frames silently, since they are used only to
 908          * control station power saving mode. */
 909         if (ieee80211_is_nullfunc(hdr->frame_control)) {
 910                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
 911                 /* Update counter and free packet here to avoid counting this
 912                  * as a dropped packed. */
 913                 sta->rx_packets++;
 914                 dev_kfree_skb(rx->skb);
 915                 return RX_QUEUED;
 916         }
 917
 918         return RX_CONTINUE;
 919 } /* ieee80211_rx_h_sta_process */
 920
 921 static inline struct ieee80211_fragment_entry *
 922 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
 923                          unsigned int frag, unsigned int seq, int rx_queue,
 924                          struct sk_buff **skb)
 925 {
 926         struct ieee80211_fragment_entry *entry;
 927         int idx;
 928
 929         idx = sdata->fragment_next;
 930         entry = &sdata->fragments[sdata->fragment_next++];
 931         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
 932                 sdata->fragment_next = 0;
 933
 934         if (!skb_queue_empty(&entry->skb_list)) {
 935 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 936                 struct ieee80211_hdr *hdr =
 937                         (struct ieee80211_hdr *) entry->skb_list.next->data;
 938                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
 939                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
 940                        "addr1=%pM addr2=%pM\n",
 941                        sdata->dev->name, idx,
 942                        jiffies - entry->first_frag_time, entry->seq,
 943                        entry->last_frag, hdr->addr1, hdr->addr2);
 944 #endif
 945                 __skb_queue_purge(&entry->skb_list);
 946         }
 947
 948         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
 949         *skb = NULL;
 950         entry->first_frag_time = jiffies;
 951         entry->seq = seq;
 952         entry->rx_queue = rx_queue;
 953         entry->last_frag = frag;
 954         entry->ccmp = 0;
 955         entry->extra_len = 0;
 956
 957         return entry;
 958 }
 959
 960 static inline struct ieee80211_fragment_entry *
 961 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
 962                           unsigned int frag, unsigned int seq,
 963                           int rx_queue, struct ieee80211_hdr *hdr)
 964 {
 965         struct ieee80211_fragment_entry *entry;
 966         int i, idx;
 967
 968         idx = sdata->fragment_next;
 969         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
 970                 struct ieee80211_hdr *f_hdr;
 971
 972                 idx--;
 973                 if (idx < 0)
 974                         idx = IEEE80211_FRAGMENT_MAX - 1;
 975
 976                 entry = &sdata->fragments[idx];
 977                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
 978                     entry->rx_queue != rx_queue ||
 979                     entry->last_frag + 1 != frag)
 980                         continue;
 981
 982                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
 983
 984                 /*
 985                  * Check ftype and addresses are equal, else check next fragment
 986                  */
 987                 if (((hdr->frame_control ^ f_hdr->frame_control) &
 988                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
 989                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
 990                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
 991                         continue;
 992
 993                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
 994                         __skb_queue_purge(&entry->skb_list);
 995                         continue;
 996                 }
 997                 return entry;
 998         }
 999
1000         return NULL;
1001 }
1002
1003 static ieee80211_rx_result debug_noinline
1004 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1005 {
1006         struct ieee80211_hdr *hdr;
1007         u16 sc;
1008         __le16 fc;
1009         unsigned int frag, seq;
1010         struct ieee80211_fragment_entry *entry;
1011         struct sk_buff *skb;
1012
1013         hdr = (struct ieee80211_hdr *)rx->skb->data;
1014         fc = hdr->frame_control;
1015         sc = le16_to_cpu(hdr->seq_ctrl);
1016         frag = sc & IEEE80211_SCTL_FRAG;
1017
1018         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1019                    (rx->skb)->len < 24 ||
1020                    is_multicast_ether_addr(hdr->addr1))) {
1021                 /* not fragmented */
1022                 goto out;
1023         }
1024         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1025
1026         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1027
1028         if (frag == 0) {
1029                 /* This is the first fragment of a new frame. */
1030                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1031                                                  rx->queue, &(rx->skb));
1032                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
1033                     ieee80211_has_protected(fc)) {
1034                         /* Store CCMP PN so that we can verify that the next
1035                          * fragment has a sequential PN value. */
1036                         entry->ccmp = 1;
1037                         memcpy(entry->last_pn,
1038                                rx->key->u.ccmp.rx_pn[rx->queue],
1039                                CCMP_PN_LEN);
1040                 }
1041                 return RX_QUEUED;
1042         }
1043
1044         /* This is a fragment for a frame that should already be pending in
1045          * fragment cache. Add this fragment to the end of the pending entry.
1046          */
1047         entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
1048         if (!entry) {
1049                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1050                 return RX_DROP_MONITOR;
1051         }
1052
1053         /* Verify that MPDUs within one MSDU have sequential PN values.
1054          * (IEEE 802.11i, 8.3.3.4.5) */
1055         if (entry->ccmp) {
1056                 int i;
1057                 u8 pn[CCMP_PN_LEN], *rpn;
1058                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
1059                         return RX_DROP_UNUSABLE;
1060                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1061                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1062                         pn[i]++;
1063                         if (pn[i])
1064                                 break;
1065                 }
1066                 rpn = rx->key->u.ccmp.rx_pn[rx->queue];
1067                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1068                         return RX_DROP_UNUSABLE;
1069                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1070         }
1071
1072         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1073         __skb_queue_tail(&entry->skb_list, rx->skb);
1074         entry->last_frag = frag;
1075         entry->extra_len += rx->skb->len;
1076         if (ieee80211_has_morefrags(fc)) {
1077                 rx->skb = NULL;
1078                 return RX_QUEUED;
1079         }
1080
1081         rx->skb = __skb_dequeue(&entry->skb_list);
1082         if (skb_tailroom(rx->skb) < entry->extra_len) {
1083                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1084                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1085                                               GFP_ATOMIC))) {
1086                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1087                         __skb_queue_purge(&entry->skb_list);
1088                         return RX_DROP_UNUSABLE;
1089                 }
1090         }
1091         while ((skb = __skb_dequeue(&entry->skb_list))) {
1092                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1093                 dev_kfree_skb(skb);
1094         }
1095
1096         /* Complete frame has been reassembled - process it now */
1097         rx->flags |= IEEE80211_RX_FRAGMENTED;
1098
1099  out:
1100         if (rx->sta)
1101                 rx->sta->rx_packets++;
1102         if (is_multicast_ether_addr(hdr->addr1))
1103                 rx->local->dot11MulticastReceivedFrameCount++;
1104         else
1105                 ieee80211_led_rx(rx->local);
1106         return RX_CONTINUE;
1107 }
1108
1109 static ieee80211_rx_result debug_noinline
1110 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
1111 {
1112         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1113         struct sk_buff *skb;
1114         int no_pending_pkts;
1115         __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
1116
1117         if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
1118                    !(rx->flags & IEEE80211_RX_RA_MATCH)))
1119                 return RX_CONTINUE;
1120
1121         if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1122             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1123                 return RX_DROP_UNUSABLE;
1124
1125         skb = skb_dequeue(&rx->sta->tx_filtered);
1126         if (!skb) {
1127                 skb = skb_dequeue(&rx->sta->ps_tx_buf);
1128                 if (skb)
1129                         rx->local->total_ps_buffered--;
1130         }
1131         no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
1132                 skb_queue_empty(&rx->sta->ps_tx_buf);
1133
1134         if (skb) {
1135                 struct ieee80211_hdr *hdr =
1136                         (struct ieee80211_hdr *) skb->data;
1137
1138                 /*
1139                  * Tell TX path to send one frame even though the STA may
1140                  * still remain is PS mode after this frame exchange.
1141                  */
1142                 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1143
1144 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1145                 printk(KERN_DEBUG "STA %pM aid %d: PS Poll (entries after %d)\n",
1146                        rx->sta->sta.addr, rx->sta->sta.aid,
1147                        skb_queue_len(&rx->sta->ps_tx_buf));
1148 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1149
1150                 /* Use MoreData flag to indicate whether there are more
1151                  * buffered frames for this STA */
1152                 if (no_pending_pkts)
1153                         hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
1154                 else
1155                         hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1156
1157                 dev_queue_xmit(skb);
1158
1159                 if (no_pending_pkts)
1160                         sta_info_clear_tim_bit(rx->sta);
1161 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1162         } else if (!rx->sent_ps_buffered) {
1163                 /*
1164                  * FIXME: This can be the result of a race condition between
1165                  *        us expiring a frame and the station polling for it.
1166                  *        Should we send it a null-func frame indicating we
1167                  *        have nothing buffered for it?
1168                  */
1169                 printk(KERN_DEBUG "%s: STA %pM sent PS Poll even "
1170                        "though there are no buffered frames for it\n",
1171                        rx->dev->name, rx->sta->sta.addr);
1172 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1173         }
1174
1175         /* Free PS Poll skb here instead of returning RX_DROP that would
1176          * count as an dropped frame. */
1177         dev_kfree_skb(rx->skb);
1178
1179         return RX_QUEUED;
1180 }
1181
1182 static ieee80211_rx_result debug_noinline
1183 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1184 {
1185         u8 *data = rx->skb->data;
1186         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1187
1188         if (!ieee80211_is_data_qos(hdr->frame_control))
1189                 return RX_CONTINUE;
1190
1191         /* remove the qos control field, update frame type and meta-data */
1192         memmove(data + IEEE80211_QOS_CTL_LEN, data,
1193                 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1194         hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1195         /* change frame type to non QOS */
1196         hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1197
1198         return RX_CONTINUE;
1199 }
1200
1201 static int
1202 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1203 {
1204         if (unlikely(!rx->sta ||
1205             !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1206                 return -EACCES;
1207
1208         return 0;
1209 }
1210
1211 static int
1212 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1213 {
1214         /*
1215          * Pass through unencrypted frames if the hardware has
1216          * decrypted them already.
1217          */
1218         if (rx->status->flag & RX_FLAG_DECRYPTED)
1219                 return 0;
1220
1221         /* Drop unencrypted frames if key is set. */
1222         if (unlikely(!ieee80211_has_protected(fc) &&
1223                      !ieee80211_is_nullfunc(fc) &&
1224                      ieee80211_is_data(fc) &&
1225                      (rx->key || rx->sdata->drop_unencrypted)))
1226                 return -EACCES;
1227         if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) {
1228                 if (unlikely(ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1229                              rx->key))
1230                         return -EACCES;
1231                 /* BIP does not use Protected field, so need to check MMIE */
1232                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb)
1233                              && ieee80211_get_mmie_keyidx(rx->skb) < 0 &&
1234                              rx->key))
1235                         return -EACCES;
1236                 /*
1237                  * When using MFP, Action frames are not allowed prior to
1238                  * having configured keys.
1239                  */
1240                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1241                              ieee80211_is_robust_mgmt_frame(
1242                                      (struct ieee80211_hdr *) rx->skb->data)))
1243                         return -EACCES;
1244         }
1245
1246         return 0;
1247 }
1248
1249 static int
1250 ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1251 {
1252         struct net_device *dev = rx->dev;
1253         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
1254         u16 hdrlen, ethertype;
1255         u8 *payload;
1256         u8 dst[ETH_ALEN];
1257         u8 src[ETH_ALEN] __aligned(2);
1258         struct sk_buff *skb = rx->skb;
1259         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1260
1261         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1262                 return -1;
1263
1264         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1265
1266         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
1267          * header
1268          * IEEE 802.11 address fields:
1269          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
1270          *   0     0   DA    SA    BSSID n/a
1271          *   0     1   DA    BSSID SA    n/a
1272          *   1     0   BSSID SA    DA    n/a
1273          *   1     1   RA    TA    DA    SA
1274          */
1275         memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
1276         memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);
1277
1278         switch (hdr->frame_control &
1279                 cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
1280         case cpu_to_le16(IEEE80211_FCTL_TODS):
1281                 if (unlikely(sdata->vif.type != NL80211_IFTYPE_AP &&
1282                              sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1283                         return -1;
1284                 break;
1285         case cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
1286                 if (unlikely(sdata->vif.type != NL80211_IFTYPE_WDS &&
1287                              sdata->vif.type != NL80211_IFTYPE_MESH_POINT))
1288                         return -1;
1289                 if (ieee80211_vif_is_mesh(&sdata->vif)) {
1290                         struct ieee80211s_hdr *meshdr = (struct ieee80211s_hdr *)
1291                                 (skb->data + hdrlen);
1292                         hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
1293                         if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
1294                                 memcpy(dst, meshdr->eaddr1, ETH_ALEN);
1295                                 memcpy(src, meshdr->eaddr2, ETH_ALEN);
1296                         }
1297                 }
1298                 break;
1299         case cpu_to_le16(IEEE80211_FCTL_FROMDS):
1300                 if (sdata->vif.type != NL80211_IFTYPE_STATION ||
1301                     (is_multicast_ether_addr(dst) &&
1302                      !compare_ether_addr(src, dev->dev_addr)))
1303                         return -1;
1304                 break;
1305         case cpu_to_le16(0):
1306                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1307                         return -1;
1308                 break;
1309         }
1310
1311         if (unlikely(skb->len - hdrlen < 8))
1312                 return -1;
1313
1314         payload = skb->data + hdrlen;
1315         ethertype = (payload[6] << 8) | payload[7];
1316
1317         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1318                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1319                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1320                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1321                  * replace EtherType */
1322                 skb_pull(skb, hdrlen + 6);
1323                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1324                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1325         } else {
1326                 struct ethhdr *ehdr;
1327                 __be16 len;
1328
1329                 skb_pull(skb, hdrlen);
1330                 len = htons(skb->len);
1331                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1332                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1333                 memcpy(ehdr->h_source, src, ETH_ALEN);
1334                 ehdr->h_proto = len;
1335         }
1336         return 0;
1337 }
1338
1339 /*
1340  * requires that rx->skb is a frame with ethernet header
1341  */
1342 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1343 {
1344         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1345                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1346         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1347
1348         /*
1349          * Allow EAPOL frames to us/the PAE group address regardless
1350          * of whether the frame was encrypted or not.
1351          */
1352         if (ehdr->h_proto == htons(ETH_P_PAE) &&
1353             (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
1354              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1355                 return true;
1356
1357         if (ieee80211_802_1x_port_control(rx) ||
1358             ieee80211_drop_unencrypted(rx, fc))
1359                 return false;
1360
1361         return true;
1362 }
1363
1364 /*
1365  * requires that rx->skb is a frame with ethernet header
1366  */
1367 static void
1368 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1369 {
1370         struct net_device *dev = rx->dev;
1371         struct ieee80211_local *local = rx->local;
1372         struct sk_buff *skb, *xmit_skb;
1373         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1374         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1375         struct sta_info *dsta;
1376
1377         skb = rx->skb;
1378         xmit_skb = NULL;
1379
1380         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1381              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1382             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1383             (rx->flags & IEEE80211_RX_RA_MATCH)) {
1384                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1385                         /*
1386                          * send multicast frames both to higher layers in
1387                          * local net stack and back to the wireless medium
1388                          */
1389                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1390                         if (!xmit_skb && net_ratelimit())
1391                                 printk(KERN_DEBUG "%s: failed to clone "
1392                                        "multicast frame\n", dev->name);
1393                 } else {
1394                         dsta = sta_info_get(local, skb->data);
1395                         if (dsta && dsta->sdata->dev == dev) {
1396                                 /*
1397                                  * The destination station is associated to
1398                                  * this AP (in this VLAN), so send the frame
1399                                  * directly to it and do not pass it to local
1400                                  * net stack.
1401                                  */
1402                                 xmit_skb = skb;
1403                                 skb = NULL;
1404                         }
1405                 }
1406         }
1407
1408         if (skb) {
1409                 int align __maybe_unused;
1410
1411 #if defined(CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT) || !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
1412                 /*
1413                  * 'align' will only take the values 0 or 2 here
1414                  * since all frames are required to be aligned
1415                  * to 2-byte boundaries when being passed to
1416                  * mac80211. That also explains the __skb_push()
1417                  * below.
1418                  */
1419                 align = (unsigned long)skb->data & 3;
1420                 if (align) {
1421                         if (WARN_ON(skb_headroom(skb) < 3)) {
1422                                 dev_kfree_skb(skb);
1423                                 skb = NULL;
1424                         } else {
1425                                 u8 *data = skb->data;
1426                                 size_t len = skb->len;
1427                                 u8 *new = __skb_push(skb, align);
1428                                 memmove(new, data, len);
1429                                 __skb_trim(skb, len);
1430                         }
1431                 }
1432 #endif
1433
1434                 if (skb) {
1435                         /* deliver to local stack */
1436                         skb->protocol = eth_type_trans(skb, dev);
1437                         memset(skb->cb, 0, sizeof(skb->cb));
1438                         netif_rx(skb);
1439                 }
1440         }
1441
1442         if (xmit_skb) {
1443                 /* send to wireless media */
1444                 xmit_skb->protocol = htons(ETH_P_802_3);
1445                 skb_reset_network_header(xmit_skb);
1446                 skb_reset_mac_header(xmit_skb);
1447                 dev_queue_xmit(xmit_skb);
1448         }
1449 }
1450
1451 static ieee80211_rx_result debug_noinline
1452 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1453 {
1454         struct net_device *dev = rx->dev;
1455         struct ieee80211_local *local = rx->local;
1456         u16 ethertype;
1457         u8 *payload;
1458         struct sk_buff *skb = rx->skb, *frame = NULL;
1459         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1460         __le16 fc = hdr->frame_control;
1461         const struct ethhdr *eth;
1462         int remaining, err;
1463         u8 dst[ETH_ALEN];
1464         u8 src[ETH_ALEN];
1465
1466         if (unlikely(!ieee80211_is_data(fc)))
1467                 return RX_CONTINUE;
1468
1469         if (unlikely(!ieee80211_is_data_present(fc)))
1470                 return RX_DROP_MONITOR;
1471
1472         if (!(rx->flags & IEEE80211_RX_AMSDU))
1473                 return RX_CONTINUE;
1474
1475         err = ieee80211_data_to_8023(rx);
1476         if (unlikely(err))
1477                 return RX_DROP_UNUSABLE;
1478
1479         skb->dev = dev;
1480
1481         dev->stats.rx_packets++;
1482         dev->stats.rx_bytes += skb->len;
1483
1484         /* skip the wrapping header */
1485         eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
1486         if (!eth)
1487                 return RX_DROP_UNUSABLE;
1488
1489         while (skb != frame) {
1490                 u8 padding;
1491                 __be16 len = eth->h_proto;
1492                 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
1493
1494                 remaining = skb->len;
1495                 memcpy(dst, eth->h_dest, ETH_ALEN);
1496                 memcpy(src, eth->h_source, ETH_ALEN);
1497
1498                 padding = ((4 - subframe_len) & 0x3);
1499                 /* the last MSDU has no padding */
1500                 if (subframe_len > remaining)
1501                         return RX_DROP_UNUSABLE;
1502
1503                 skb_pull(skb, sizeof(struct ethhdr));
1504                 /* if last subframe reuse skb */
1505                 if (remaining <= subframe_len + padding)
1506                         frame = skb;
1507                 else {
1508                         /*
1509                          * Allocate and reserve two bytes more for payload
1510                          * alignment since sizeof(struct ethhdr) is 14.
1511                          */
1512                         frame = dev_alloc_skb(
1513                                 ALIGN(local->hw.extra_tx_headroom, 4) +
1514                                 subframe_len + 2);
1515
1516                         if (frame == NULL)
1517                                 return RX_DROP_UNUSABLE;
1518
1519                         skb_reserve(frame,
1520                                     ALIGN(local->hw.extra_tx_headroom, 4) +
1521                                     sizeof(struct ethhdr) + 2);
1522                         memcpy(skb_put(frame, ntohs(len)), skb->data,
1523                                 ntohs(len));
1524
1525                         eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
1526                                                         padding);
1527                         if (!eth) {
1528                                 dev_kfree_skb(frame);
1529                                 return RX_DROP_UNUSABLE;
1530                         }
1531                 }
1532
1533                 skb_reset_network_header(frame);
1534                 frame->dev = dev;
1535                 frame->priority = skb->priority;
1536                 rx->skb = frame;
1537
1538                 payload = frame->data;
1539                 ethertype = (payload[6] << 8) | payload[7];
1540
1541                 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1542                             ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1543                            compare_ether_addr(payload,
1544                                               bridge_tunnel_header) == 0)) {
1545                         /* remove RFC1042 or Bridge-Tunnel
1546                          * encapsulation and replace EtherType */
1547                         skb_pull(frame, 6);
1548                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1549                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1550                 } else {
1551                         memcpy(skb_push(frame, sizeof(__be16)),
1552                                &len, sizeof(__be16));
1553                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1554                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1555                 }
1556
1557                 if (!ieee80211_frame_allowed(rx, fc)) {
1558                         if (skb == frame) /* last frame */
1559                                 return RX_DROP_UNUSABLE;
1560                         dev_kfree_skb(frame);
1561                         continue;
1562                 }
1563
1564                 ieee80211_deliver_skb(rx);
1565         }
1566
1567         return RX_QUEUED;
1568 }
1569
1570 #ifdef CONFIG_MAC80211_MESH
1571 static ieee80211_rx_result
1572 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1573 {
1574         struct ieee80211_hdr *hdr;
1575         struct ieee80211s_hdr *mesh_hdr;
1576         unsigned int hdrlen;
1577         struct sk_buff *skb = rx->skb, *fwd_skb;
1578
1579         hdr = (struct ieee80211_hdr *) skb->data;
1580         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1581         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1582
1583         if (!ieee80211_is_data(hdr->frame_control))
1584                 return RX_CONTINUE;
1585
1586         if (!mesh_hdr->ttl)
1587                 /* illegal frame */
1588                 return RX_DROP_MONITOR;
1589
1590         if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6){
1591                 struct ieee80211_sub_if_data *sdata;
1592                 struct mesh_path *mppath;
1593
1594                 sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1595                 rcu_read_lock();
1596                 mppath = mpp_path_lookup(mesh_hdr->eaddr2, sdata);
1597                 if (!mppath) {
1598                         mpp_path_add(mesh_hdr->eaddr2, hdr->addr4, sdata);
1599                 } else {
1600                         spin_lock_bh(&mppath->state_lock);
1601                         mppath->exp_time = jiffies;
1602                         if (compare_ether_addr(mppath->mpp, hdr->addr4) != 0)
1603                                 memcpy(mppath->mpp, hdr->addr4, ETH_ALEN);
1604                         spin_unlock_bh(&mppath->state_lock);
1605                 }
1606                 rcu_read_unlock();
1607         }
1608
1609         if (compare_ether_addr(rx->dev->dev_addr, hdr->addr3) == 0)
1610                 return RX_CONTINUE;
1611
1612         mesh_hdr->ttl--;
1613
1614         if (rx->flags & IEEE80211_RX_RA_MATCH) {
1615                 if (!mesh_hdr->ttl)
1616                         IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1617                                                      dropped_frames_ttl);
1618                 else {
1619                         struct ieee80211_hdr *fwd_hdr;
1620                         fwd_skb = skb_copy(skb, GFP_ATOMIC);
1621
1622                         if (!fwd_skb && net_ratelimit())
1623                                 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1624                                                    rx->dev->name);
1625
1626                         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1627                         /*
1628                          * Save TA to addr1 to send TA a path error if a
1629                          * suitable next hop is not found
1630                          */
1631                         memcpy(fwd_hdr->addr1, fwd_hdr->addr2, ETH_ALEN);
1632                         memcpy(fwd_hdr->addr2, rx->dev->dev_addr, ETH_ALEN);
1633                         fwd_skb->dev = rx->local->mdev;
1634                         fwd_skb->iif = rx->dev->ifindex;
1635                         dev_queue_xmit(fwd_skb);
1636                 }
1637         }
1638
1639         if (is_multicast_ether_addr(hdr->addr3) ||
1640             rx->dev->flags & IFF_PROMISC)
1641                 return RX_CONTINUE;
1642         else
1643                 return RX_DROP_MONITOR;
1644 }
1645 #endif
1646
1647 static ieee80211_rx_result debug_noinline
1648 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1649 {
1650         struct net_device *dev = rx->dev;
1651         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1652         __le16 fc = hdr->frame_control;
1653         int err;
1654
1655         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1656                 return RX_CONTINUE;
1657
1658         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1659                 return RX_DROP_MONITOR;
1660
1661         err = ieee80211_data_to_8023(rx);
1662         if (unlikely(err))
1663                 return RX_DROP_UNUSABLE;
1664
1665         if (!ieee80211_frame_allowed(rx, fc))
1666                 return RX_DROP_MONITOR;
1667
1668         rx->skb->dev = dev;
1669
1670         dev->stats.rx_packets++;
1671         dev->stats.rx_bytes += rx->skb->len;
1672
1673         ieee80211_deliver_skb(rx);
1674
1675         return RX_QUEUED;
1676 }
1677
1678 static ieee80211_rx_result debug_noinline
1679 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
1680 {
1681         struct ieee80211_local *local = rx->local;
1682         struct ieee80211_hw *hw = &local->hw;
1683         struct sk_buff *skb = rx->skb;
1684         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1685         struct tid_ampdu_rx *tid_agg_rx;
1686         u16 start_seq_num;
1687         u16 tid;
1688
1689         if (likely(!ieee80211_is_ctl(bar->frame_control)))
1690                 return RX_CONTINUE;
1691
1692         if (ieee80211_is_back_req(bar->frame_control)) {
1693                 if (!rx->sta)
1694                         return RX_CONTINUE;
1695                 tid = le16_to_cpu(bar->control) >> 12;
1696                 if (rx->sta->ampdu_mlme.tid_state_rx[tid]
1697                                         != HT_AGG_STATE_OPERATIONAL)
1698                         return RX_CONTINUE;
1699                 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid];
1700
1701                 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1702
1703                 /* reset session timer */
1704                 if (tid_agg_rx->timeout)
1705                         mod_timer(&tid_agg_rx->session_timer,
1706                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
1707
1708                 /* manage reordering buffer according to requested */
1709                 /* sequence number */
1710                 rcu_read_lock();
1711                 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL, NULL,
1712                                                  start_seq_num, 1);
1713                 rcu_read_unlock();
1714                 return RX_DROP_UNUSABLE;
1715         }
1716
1717         return RX_CONTINUE;
1718 }
1719
1720 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
1721                                            struct ieee80211_mgmt *mgmt,
1722                                            size_t len)
1723 {
1724         struct ieee80211_local *local = sdata->local;
1725         struct sk_buff *skb;
1726         struct ieee80211_mgmt *resp;
1727
1728         if (compare_ether_addr(mgmt->da, sdata->dev->dev_addr) != 0) {
1729                 /* Not to own unicast address */
1730                 return;
1731         }
1732
1733         if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
1734             compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
1735                 /* Not from the current AP. */
1736                 return;
1737         }
1738
1739         if (sdata->u.mgd.state == IEEE80211_STA_MLME_ASSOCIATE) {
1740                 /* Association in progress; ignore SA Query */
1741                 return;
1742         }
1743
1744         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
1745                 /* Too short SA Query request frame */
1746                 return;
1747         }
1748
1749         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
1750         if (skb == NULL)
1751                 return;
1752
1753         skb_reserve(skb, local->hw.extra_tx_headroom);
1754         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
1755         memset(resp, 0, 24);
1756         memcpy(resp->da, mgmt->sa, ETH_ALEN);
1757         memcpy(resp->sa, sdata->dev->dev_addr, ETH_ALEN);
1758         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
1759         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1760                                           IEEE80211_STYPE_ACTION);
1761         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
1762         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
1763         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
1764         memcpy(resp->u.action.u.sa_query.trans_id,
1765                mgmt->u.action.u.sa_query.trans_id,
1766                WLAN_SA_QUERY_TR_ID_LEN);
1767
1768         ieee80211_tx_skb(sdata, skb, 1);
1769 }
1770
1771 static ieee80211_rx_result debug_noinline
1772 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
1773 {
1774         struct ieee80211_local *local = rx->local;
1775         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1776         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1777         struct ieee80211_bss *bss;
1778         int len = rx->skb->len;
1779
1780         if (!ieee80211_is_action(mgmt->frame_control))
1781                 return RX_CONTINUE;
1782
1783         if (!rx->sta)
1784                 return RX_DROP_MONITOR;
1785
1786         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1787                 return RX_DROP_MONITOR;
1788
1789         if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
1790                 return RX_DROP_MONITOR;
1791
1792         /* all categories we currently handle have action_code */
1793         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
1794                 return RX_DROP_MONITOR;
1795
1796         switch (mgmt->u.action.category) {
1797         case WLAN_CATEGORY_BACK:
1798                 /*
1799                  * The aggregation code is not prepared to handle
1800                  * anything but STA/AP due to the BSSID handling;
1801                  * IBSS could work in the code but isn't supported
1802                  * by drivers or the standard.
1803                  */
1804                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
1805                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
1806                     sdata->vif.type != NL80211_IFTYPE_AP)
1807                         return RX_DROP_MONITOR;
1808
1809                 switch (mgmt->u.action.u.addba_req.action_code) {
1810                 case WLAN_ACTION_ADDBA_REQ:
1811                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1812                                    sizeof(mgmt->u.action.u.addba_req)))
1813                                 return RX_DROP_MONITOR;
1814                         ieee80211_process_addba_request(local, rx->sta, mgmt, len);
1815                         break;
1816                 case WLAN_ACTION_ADDBA_RESP:
1817                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1818                                    sizeof(mgmt->u.action.u.addba_resp)))
1819                                 return RX_DROP_MONITOR;
1820                         ieee80211_process_addba_resp(local, rx->sta, mgmt, len);
1821                         break;
1822                 case WLAN_ACTION_DELBA:
1823                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1824                                    sizeof(mgmt->u.action.u.delba)))
1825                                 return RX_DROP_MONITOR;
1826                         ieee80211_process_delba(sdata, rx->sta, mgmt, len);
1827                         break;
1828                 }
1829                 break;
1830         case WLAN_CATEGORY_SPECTRUM_MGMT:
1831                 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
1832                         return RX_DROP_MONITOR;
1833
1834                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
1835                         return RX_DROP_MONITOR;
1836
1837                 switch (mgmt->u.action.u.measurement.action_code) {
1838                 case WLAN_ACTION_SPCT_MSR_REQ:
1839                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1840                                    sizeof(mgmt->u.action.u.measurement)))
1841                                 return RX_DROP_MONITOR;
1842                         ieee80211_process_measurement_req(sdata, mgmt, len);
1843                         break;
1844                 case WLAN_ACTION_SPCT_CHL_SWITCH:
1845                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1846                                    sizeof(mgmt->u.action.u.chan_switch)))
1847                                 return RX_DROP_MONITOR;
1848
1849                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
1850                                 return RX_DROP_MONITOR;
1851
1852                         if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
1853                                 return RX_DROP_MONITOR;
1854
1855                         bss = ieee80211_rx_bss_get(local, sdata->u.mgd.bssid,
1856                                            local->hw.conf.channel->center_freq,
1857                                            sdata->u.mgd.ssid,
1858                                            sdata->u.mgd.ssid_len);
1859                         if (!bss)
1860                                 return RX_DROP_MONITOR;
1861
1862                         ieee80211_sta_process_chanswitch(sdata,
1863                                      &mgmt->u.action.u.chan_switch.sw_elem, bss);
1864                         ieee80211_rx_bss_put(local, bss);
1865                         break;
1866                 }
1867                 break;
1868         case WLAN_CATEGORY_SA_QUERY:
1869                 if (len < (IEEE80211_MIN_ACTION_SIZE +
1870                            sizeof(mgmt->u.action.u.sa_query)))
1871                         return RX_DROP_MONITOR;
1872                 switch (mgmt->u.action.u.sa_query.action) {
1873                 case WLAN_ACTION_SA_QUERY_REQUEST:
1874                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
1875                                 return RX_DROP_MONITOR;
1876                         ieee80211_process_sa_query_req(sdata, mgmt, len);
1877                         break;
1878                 case WLAN_ACTION_SA_QUERY_RESPONSE:
1879                         /*
1880                          * SA Query response is currently only used in AP mode
1881                          * and it is processed in user space.
1882                          */
1883                         return RX_CONTINUE;
1884                 }
1885                 break;
1886         default:
1887                 return RX_CONTINUE;
1888         }
1889
1890         rx->sta->rx_packets++;
1891         dev_kfree_skb(rx->skb);
1892         return RX_QUEUED;
1893 }
1894
1895 static ieee80211_rx_result debug_noinline
1896 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
1897 {
1898         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1899         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1900
1901         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1902                 return RX_DROP_MONITOR;
1903
1904         if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
1905                 return RX_DROP_MONITOR;
1906
1907         if (ieee80211_vif_is_mesh(&sdata->vif))
1908                 return ieee80211_mesh_rx_mgmt(sdata, rx->skb, rx->status);
1909
1910         if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
1911                 return ieee80211_ibss_rx_mgmt(sdata, rx->skb, rx->status);
1912
1913         if (sdata->vif.type == NL80211_IFTYPE_STATION)
1914                 return ieee80211_sta_rx_mgmt(sdata, rx->skb, rx->status);
1915
1916         return RX_DROP_MONITOR;
1917 }
1918
1919 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1920                                             struct ieee80211_hdr *hdr,
1921                                             struct ieee80211_rx_data *rx)
1922 {
1923         int keyidx;
1924         unsigned int hdrlen;
1925
1926         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1927         if (rx->skb->len >= hdrlen + 4)
1928                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1929         else
1930                 keyidx = -1;
1931
1932         if (!rx->sta) {
1933                 /*
1934                  * Some hardware seem to generate incorrect Michael MIC
1935                  * reports; ignore them to avoid triggering countermeasures.
1936                  */
1937                 goto ignore;
1938         }
1939
1940         if (!ieee80211_has_protected(hdr->frame_control))
1941                 goto ignore;
1942
1943         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
1944                 /*
1945                  * APs with pairwise keys should never receive Michael MIC
1946                  * errors for non-zero keyidx because these are reserved for
1947                  * group keys and only the AP is sending real multicast
1948                  * frames in the BSS.
1949                  */
1950                 goto ignore;
1951         }
1952
1953         if (!ieee80211_is_data(hdr->frame_control) &&
1954             !ieee80211_is_auth(hdr->frame_control))
1955                 goto ignore;
1956
1957         mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL);
1958  ignore:
1959         dev_kfree_skb(rx->skb);
1960         rx->skb = NULL;
1961 }
1962
1963 /* TODO: use IEEE80211_RX_FRAGMENTED */
1964 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx)
1965 {
1966         struct ieee80211_sub_if_data *sdata;
1967         struct ieee80211_local *local = rx->local;
1968         struct ieee80211_rtap_hdr {
1969                 struct ieee80211_radiotap_header hdr;
1970                 u8 flags;
1971                 u8 rate;
1972                 __le16 chan_freq;
1973                 __le16 chan_flags;
1974         } __attribute__ ((packed)) *rthdr;
1975         struct sk_buff *skb = rx->skb, *skb2;
1976         struct net_device *prev_dev = NULL;
1977         struct ieee80211_rx_status *status = rx->status;
1978
1979         if (rx->flags & IEEE80211_RX_CMNTR_REPORTED)
1980                 goto out_free_skb;
1981
1982         if (skb_headroom(skb) < sizeof(*rthdr) &&
1983             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
1984                 goto out_free_skb;
1985
1986         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
1987         memset(rthdr, 0, sizeof(*rthdr));
1988         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
1989         rthdr->hdr.it_present =
1990                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
1991                             (1 << IEEE80211_RADIOTAP_RATE) |
1992                             (1 << IEEE80211_RADIOTAP_CHANNEL));
1993
1994         rthdr->rate = rx->rate->bitrate / 5;
1995         rthdr->chan_freq = cpu_to_le16(status->freq);
1996
1997         if (status->band == IEEE80211_BAND_5GHZ)
1998                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
1999                                                 IEEE80211_CHAN_5GHZ);
2000         else
2001                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
2002                                                 IEEE80211_CHAN_2GHZ);
2003
2004         skb_set_mac_header(skb, 0);
2005         skb->ip_summed = CHECKSUM_UNNECESSARY;
2006         skb->pkt_type = PACKET_OTHERHOST;
2007         skb->protocol = htons(ETH_P_802_2);
2008
2009         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2010                 if (!netif_running(sdata->dev))
2011                         continue;
2012
2013                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2014                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2015                         continue;
2016
2017                 if (prev_dev) {
2018                         skb2 = skb_clone(skb, GFP_ATOMIC);
2019                         if (skb2) {
2020                                 skb2->dev = prev_dev;
2021                                 netif_rx(skb2);
2022                         }
2023                 }
2024
2025                 prev_dev = sdata->dev;
2026                 sdata->dev->stats.rx_packets++;
2027                 sdata->dev->stats.rx_bytes += skb->len;
2028         }
2029
2030         if (prev_dev) {
2031                 skb->dev = prev_dev;
2032                 netif_rx(skb);
2033                 skb = NULL;
2034         } else
2035                 goto out_free_skb;
2036
2037         rx->flags |= IEEE80211_RX_CMNTR_REPORTED;
2038         return;
2039
2040  out_free_skb:
2041         dev_kfree_skb(skb);
2042 }
2043
2044
2045 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
2046                                          struct ieee80211_rx_data *rx,
2047                                          struct sk_buff *skb)
2048 {
2049         ieee80211_rx_result res = RX_DROP_MONITOR;
2050
2051         rx->skb = skb;
2052         rx->sdata = sdata;
2053         rx->dev = sdata->dev;
2054
2055 #define CALL_RXH(rxh)                   \
2056         do {                            \
2057                 res = rxh(rx);          \
2058                 if (res != RX_CONTINUE) \
2059                         goto rxh_done;  \
2060         } while (0);
2061
2062         CALL_RXH(ieee80211_rx_h_passive_scan)
2063         CALL_RXH(ieee80211_rx_h_check)
2064         CALL_RXH(ieee80211_rx_h_decrypt)
2065         CALL_RXH(ieee80211_rx_h_check_more_data)
2066         CALL_RXH(ieee80211_rx_h_sta_process)
2067         CALL_RXH(ieee80211_rx_h_defragment)
2068         CALL_RXH(ieee80211_rx_h_ps_poll)
2069         CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2070         /* must be after MMIC verify so header is counted in MPDU mic */
2071         CALL_RXH(ieee80211_rx_h_remove_qos_control)
2072         CALL_RXH(ieee80211_rx_h_amsdu)
2073 #ifdef CONFIG_MAC80211_MESH
2074         if (ieee80211_vif_is_mesh(&sdata->vif))
2075                 CALL_RXH(ieee80211_rx_h_mesh_fwding);
2076 #endif
2077         CALL_RXH(ieee80211_rx_h_data)
2078         CALL_RXH(ieee80211_rx_h_ctrl)
2079         CALL_RXH(ieee80211_rx_h_action)
2080         CALL_RXH(ieee80211_rx_h_mgmt)
2081
2082 #undef CALL_RXH
2083
2084  rxh_done:
2085         switch (res) {
2086         case RX_DROP_MONITOR:
2087                 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2088                 if (rx->sta)
2089                         rx->sta->rx_dropped++;
2090                 /* fall through */
2091         case RX_CONTINUE:
2092                 ieee80211_rx_cooked_monitor(rx);
2093                 break;
2094         case RX_DROP_UNUSABLE:
2095                 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2096                 if (rx->sta)
2097                         rx->sta->rx_dropped++;
2098                 dev_kfree_skb(rx->skb);
2099                 break;
2100         case RX_QUEUED:
2101                 I802_DEBUG_INC(sdata->local->rx_handlers_queued);
2102                 break;
2103         }
2104 }
2105
2106 /* main receive path */
2107
2108 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
2109                                 struct ieee80211_rx_data *rx,
2110                                 struct ieee80211_hdr *hdr)
2111 {
2112         u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, sdata->vif.type);
2113         int multicast = is_multicast_ether_addr(hdr->addr1);
2114
2115         switch (sdata->vif.type) {
2116         case NL80211_IFTYPE_STATION:
2117                 if (!bssid)
2118                         return 0;
2119                 if (!ieee80211_bssid_match(bssid, sdata->u.mgd.bssid)) {
2120                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2121                                 return 0;
2122                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2123                 } else if (!multicast &&
2124                            compare_ether_addr(sdata->dev->dev_addr,
2125                                               hdr->addr1) != 0) {
2126                         if (!(sdata->dev->flags & IFF_PROMISC))
2127                                 return 0;
2128                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2129                 }
2130                 break;
2131         case NL80211_IFTYPE_ADHOC:
2132                 if (!bssid)
2133                         return 0;
2134                 if (ieee80211_is_beacon(hdr->frame_control)) {
2135                         return 1;
2136                 }
2137                 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2138                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2139                                 return 0;
2140                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2141                 } else if (!multicast &&
2142                            compare_ether_addr(sdata->dev->dev_addr,
2143                                               hdr->addr1) != 0) {
2144                         if (!(sdata->dev->flags & IFF_PROMISC))
2145                                 return 0;
2146                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2147                 } else if (!rx->sta) {
2148                         int rate_idx;
2149                         if (rx->status->flag & RX_FLAG_HT)
2150                                 rate_idx = 0; /* TODO: HT rates */
2151                         else
2152                                 rate_idx = rx->status->rate_idx;
2153                         rx->sta = ieee80211_ibss_add_sta(sdata, bssid, hdr->addr2,
2154                                 BIT(rate_idx));
2155                 }
2156                 break;
2157         case NL80211_IFTYPE_MESH_POINT:
2158                 if (!multicast &&
2159                     compare_ether_addr(sdata->dev->dev_addr,
2160                                        hdr->addr1) != 0) {
2161                         if (!(sdata->dev->flags & IFF_PROMISC))
2162                                 return 0;
2163
2164                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2165                 }
2166                 break;
2167         case NL80211_IFTYPE_AP_VLAN:
2168         case NL80211_IFTYPE_AP:
2169                 if (!bssid) {
2170                         if (compare_ether_addr(sdata->dev->dev_addr,
2171                                                hdr->addr1))
2172                                 return 0;
2173                 } else if (!ieee80211_bssid_match(bssid,
2174                                         sdata->dev->dev_addr)) {
2175                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2176                                 return 0;
2177                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2178                 }
2179                 break;
2180         case NL80211_IFTYPE_WDS:
2181                 if (bssid || !ieee80211_is_data(hdr->frame_control))
2182                         return 0;
2183                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2184                         return 0;
2185                 break;
2186         case NL80211_IFTYPE_MONITOR:
2187                 /* take everything */
2188                 break;
2189         case NL80211_IFTYPE_UNSPECIFIED:
2190         case __NL80211_IFTYPE_AFTER_LAST:
2191                 /* should never get here */
2192                 WARN_ON(1);
2193                 break;
2194         }
2195
2196         return 1;
2197 }
2198
2199 /*
2200  * This is the actual Rx frames handler. as it blongs to Rx path it must
2201  * be called with rcu_read_lock protection.
2202  */
2203 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2204                                          struct sk_buff *skb,
2205                                          struct ieee80211_rx_status *status,
2206                                          struct ieee80211_rate *rate)
2207 {
2208         struct ieee80211_local *local = hw_to_local(hw);
2209         struct ieee80211_sub_if_data *sdata;
2210         struct ieee80211_hdr *hdr;
2211         struct ieee80211_rx_data rx;
2212         int prepares;
2213         struct ieee80211_sub_if_data *prev = NULL;
2214         struct sk_buff *skb_new;
2215
2216         hdr = (struct ieee80211_hdr *)skb->data;
2217         memset(&rx, 0, sizeof(rx));
2218         rx.skb = skb;
2219         rx.local = local;
2220
2221         rx.status = status;
2222         rx.rate = rate;
2223
2224         if (ieee80211_is_data(hdr->frame_control) || ieee80211_is_mgmt(hdr->frame_control))
2225                 local->dot11ReceivedFragmentCount++;
2226
2227         rx.sta = sta_info_get(local, hdr->addr2);
2228         if (rx.sta) {
2229                 rx.sdata = rx.sta->sdata;
2230                 rx.dev = rx.sta->sdata->dev;
2231         }
2232
2233         if ((status->flag & RX_FLAG_MMIC_ERROR)) {
2234                 ieee80211_rx_michael_mic_report(local->mdev, hdr, &rx);
2235                 return;
2236         }
2237
2238         if (unlikely(local->sw_scanning || local->hw_scanning))
2239                 rx.flags |= IEEE80211_RX_IN_SCAN;
2240
2241         ieee80211_parse_qos(&rx);
2242         ieee80211_verify_alignment(&rx);
2243
2244         skb = rx.skb;
2245
2246         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2247                 if (!netif_running(sdata->dev))
2248                         continue;
2249
2250                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR)
2251                         continue;
2252
2253                 rx.flags |= IEEE80211_RX_RA_MATCH;
2254                 prepares = prepare_for_handlers(sdata, &rx, hdr);
2255
2256                 if (!prepares)
2257                         continue;
2258
2259                 /*
2260                  * frame is destined for this interface, but if it's not
2261                  * also for the previous one we handle that after the
2262                  * loop to avoid copying the SKB once too much
2263                  */
2264
2265                 if (!prev) {
2266                         prev = sdata;
2267                         continue;
2268                 }
2269
2270                 /*
2271                  * frame was destined for the previous interface
2272                  * so invoke RX handlers for it
2273                  */
2274
2275                 skb_new = skb_copy(skb, GFP_ATOMIC);
2276                 if (!skb_new) {
2277                         if (net_ratelimit())
2278                                 printk(KERN_DEBUG "%s: failed to copy "
2279                                        "multicast frame for %s\n",
2280                                        wiphy_name(local->hw.wiphy),
2281                                        prev->dev->name);
2282                         continue;
2283                 }
2284                 ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
2285                 prev = sdata;
2286         }
2287         if (prev)
2288                 ieee80211_invoke_rx_handlers(prev, &rx, skb);
2289         else
2290                 dev_kfree_skb(skb);
2291 }
2292
2293 #define SEQ_MODULO 0x1000
2294 #define SEQ_MASK   0xfff
2295
2296 static inline int seq_less(u16 sq1, u16 sq2)
2297 {
2298         return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
2299 }
2300
2301 static inline u16 seq_inc(u16 sq)
2302 {
2303         return (sq + 1) & SEQ_MASK;
2304 }
2305
2306 static inline u16 seq_sub(u16 sq1, u16 sq2)
2307 {
2308         return (sq1 - sq2) & SEQ_MASK;
2309 }
2310
2311
2312 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
2313                                             struct tid_ampdu_rx *tid_agg_rx,
2314                                             int index)
2315 {
2316         struct ieee80211_supported_band *sband;
2317         struct ieee80211_rate *rate;
2318         struct ieee80211_rx_status status;
2319
2320         if (!tid_agg_rx->reorder_buf[index])
2321                 goto no_frame;
2322
2323         /* release the reordered frames to stack */
2324         memcpy(&status, tid_agg_rx->reorder_buf[index]->cb, sizeof(status));
2325         sband = hw->wiphy->bands[status.band];
2326         if (status.flag & RX_FLAG_HT)
2327                 rate = sband->bitrates; /* TODO: HT rates */
2328         else
2329                 rate = &sband->bitrates[status.rate_idx];
2330         __ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index],
2331                                      &status, rate);
2332         tid_agg_rx->stored_mpdu_num--;
2333         tid_agg_rx->reorder_buf[index] = NULL;
2334
2335 no_frame:
2336         tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
2337 }
2338
2339
2340 /*
2341  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
2342  * the skb was added to the buffer longer than this time ago, the earlier
2343  * frames that have not yet been received are assumed to be lost and the skb
2344  * can be released for processing. This may also release other skb's from the
2345  * reorder buffer if there are no additional gaps between the frames.
2346  */
2347 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
2348
2349 /*
2350  * As it function blongs to Rx path it must be called with
2351  * the proper rcu_read_lock protection for its flow.
2352  */
2353 static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
2354                                            struct tid_ampdu_rx *tid_agg_rx,
2355                                            struct sk_buff *skb,
2356                                            struct ieee80211_rx_status *rxstatus,
2357                                            u16 mpdu_seq_num,
2358                                            int bar_req)
2359 {
2360         u16 head_seq_num, buf_size;
2361         int index;
2362
2363         buf_size = tid_agg_rx->buf_size;
2364         head_seq_num = tid_agg_rx->head_seq_num;
2365
2366         /* frame with out of date sequence number */
2367         if (seq_less(mpdu_seq_num, head_seq_num)) {
2368                 dev_kfree_skb(skb);
2369                 return 1;
2370         }
2371
2372         /* if frame sequence number exceeds our buffering window size or
2373          * block Ack Request arrived - release stored frames */
2374         if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
2375                 /* new head to the ordering buffer */
2376                 if (bar_req)
2377                         head_seq_num = mpdu_seq_num;
2378                 else
2379                         head_seq_num =
2380                                 seq_inc(seq_sub(mpdu_seq_num, buf_size));
2381                 /* release stored frames up to new head to stack */
2382                 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
2383                         index = seq_sub(tid_agg_rx->head_seq_num,
2384                                 tid_agg_rx->ssn)
2385                                 % tid_agg_rx->buf_size;
2386                         ieee80211_release_reorder_frame(hw, tid_agg_rx,
2387                                                         index);
2388                 }
2389                 if (bar_req)
2390                         return 1;
2391         }
2392
2393         /* now the new frame is always in the range of the reordering */
2394         /* buffer window */
2395         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
2396                                 % tid_agg_rx->buf_size;
2397         /* check if we already stored this frame */
2398         if (tid_agg_rx->reorder_buf[index]) {
2399                 dev_kfree_skb(skb);
2400                 return 1;
2401         }
2402
2403         /* if arrived mpdu is in the right order and nothing else stored */
2404         /* release it immediately */
2405         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
2406                         tid_agg_rx->stored_mpdu_num == 0) {
2407                 tid_agg_rx->head_seq_num =
2408                         seq_inc(tid_agg_rx->head_seq_num);
2409                 return 0;
2410         }
2411
2412         /* put the frame in the reordering buffer */
2413         tid_agg_rx->reorder_buf[index] = skb;
2414         tid_agg_rx->reorder_time[index] = jiffies;
2415         memcpy(tid_agg_rx->reorder_buf[index]->cb, rxstatus,
2416                sizeof(*rxstatus));
2417         tid_agg_rx->stored_mpdu_num++;
2418         /* release the buffer until next missing frame */
2419         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
2420                                                 % tid_agg_rx->buf_size;
2421         if (!tid_agg_rx->reorder_buf[index] &&
2422             tid_agg_rx->stored_mpdu_num > 1) {
2423                 /*
2424                  * No buffers ready to be released, but check whether any
2425                  * frames in the reorder buffer have timed out.
2426                  */
2427                 int j;
2428                 int skipped = 1;
2429                 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
2430                      j = (j + 1) % tid_agg_rx->buf_size) {
2431                         if (tid_agg_rx->reorder_buf[j] == NULL) {
2432                                 skipped++;
2433                                 continue;
2434                         }
2435                         if (!time_after(jiffies, tid_agg_rx->reorder_time[j] +
2436                                         HZ / 10))
2437                                 break;
2438
2439 #ifdef CONFIG_MAC80211_HT_DEBUG
2440                         if (net_ratelimit())
2441                                 printk(KERN_DEBUG "%s: release an RX reorder "
2442                                        "frame due to timeout on earlier "
2443                                        "frames\n",
2444                                        wiphy_name(hw->wiphy));
2445 #endif
2446                         ieee80211_release_reorder_frame(hw, tid_agg_rx, j);
2447
2448                         /*
2449                          * Increment the head seq# also for the skipped slots.
2450                          */
2451                         tid_agg_rx->head_seq_num =
2452                                 (tid_agg_rx->head_seq_num + skipped) &
2453                                 SEQ_MASK;
2454                         skipped = 0;
2455                 }
2456         } else while (tid_agg_rx->reorder_buf[index]) {
2457                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
2458                 index = seq_sub(tid_agg_rx->head_seq_num,
2459                         tid_agg_rx->ssn) % tid_agg_rx->buf_size;
2460         }
2461         return 1;
2462 }
2463
2464 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
2465                                      struct sk_buff *skb,
2466                                      struct ieee80211_rx_status *status)
2467 {
2468         struct ieee80211_hw *hw = &local->hw;
2469         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
2470         struct sta_info *sta;
2471         struct tid_ampdu_rx *tid_agg_rx;
2472         u16 sc;
2473         u16 mpdu_seq_num;
2474         u8 ret = 0;
2475         int tid;
2476
2477         sta = sta_info_get(local, hdr->addr2);
2478         if (!sta)
2479                 return ret;
2480
2481         /* filter the QoS data rx stream according to
2482          * STA/TID and check if this STA/TID is on aggregation */
2483         if (!ieee80211_is_data_qos(hdr->frame_control))
2484                 goto end_reorder;
2485
2486         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
2487
2488         if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
2489                 goto end_reorder;
2490
2491         tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
2492
2493         /* qos null data frames are excluded */
2494         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
2495                 goto end_reorder;
2496
2497         /* new un-ordered ampdu frame - process it */
2498
2499         /* reset session timer */
2500         if (tid_agg_rx->timeout)
2501                 mod_timer(&tid_agg_rx->session_timer,
2502                           TU_TO_EXP_TIME(tid_agg_rx->timeout));
2503
2504         /* if this mpdu is fragmented - terminate rx aggregation session */
2505         sc = le16_to_cpu(hdr->seq_ctrl);
2506         if (sc & IEEE80211_SCTL_FRAG) {
2507                 ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
2508                         tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
2509                 ret = 1;
2510                 goto end_reorder;
2511         }
2512
2513         /* according to mpdu sequence number deal with reordering buffer */
2514         mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
2515         ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb, status,
2516                                                 mpdu_seq_num, 0);
2517  end_reorder:
2518         return ret;
2519 }
2520
2521 /*
2522  * This is the receive path handler. It is called by a low level driver when an
2523  * 802.11 MPDU is received from the hardware.
2524  */
2525 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
2526                     struct ieee80211_rx_status *status)
2527 {
2528         struct ieee80211_local *local = hw_to_local(hw);
2529         struct ieee80211_rate *rate = NULL;
2530         struct ieee80211_supported_band *sband;
2531
2532         if (status->band < 0 ||
2533             status->band >= IEEE80211_NUM_BANDS) {
2534                 WARN_ON(1);
2535                 return;
2536         }
2537
2538         sband = local->hw.wiphy->bands[status->band];
2539         if (!sband) {
2540                 WARN_ON(1);
2541                 return;
2542         }
2543
2544         if (status->flag & RX_FLAG_HT) {
2545                 /* rate_idx is MCS index */
2546                 if (WARN_ON(status->rate_idx < 0 ||
2547                             status->rate_idx >= 76))
2548                         return;
2549                 /* HT rates are not in the table - use the highest legacy rate
2550                  * for now since other parts of mac80211 may not yet be fully
2551                  * MCS aware. */
2552                 rate = &sband->bitrates[sband->n_bitrates - 1];
2553         } else {
2554                 if (WARN_ON(status->rate_idx < 0 ||
2555                             status->rate_idx >= sband->n_bitrates))
2556                         return;
2557                 rate = &sband->bitrates[status->rate_idx];
2558         }
2559
2560         /*
2561          * key references and virtual interfaces are protected using RCU
2562          * and this requires that we are in a read-side RCU section during
2563          * receive processing
2564          */
2565         rcu_read_lock();
2566
2567         /*
2568          * Frames with failed FCS/PLCP checksum are not returned,
2569          * all other frames are returned without radiotap header
2570          * if it was previously present.
2571          * Also, frames with less than 16 bytes are dropped.
2572          */
2573         skb = ieee80211_rx_monitor(local, skb, status, rate);
2574         if (!skb) {
2575                 rcu_read_unlock();
2576                 return;
2577         }
2578
2579         /*
2580          * In theory, the block ack reordering should happen after duplicate
2581          * removal (ieee80211_rx_h_check(), which is an RX handler). As such,
2582          * the call to ieee80211_rx_reorder_ampdu() should really be moved to
2583          * happen as a new RX handler between ieee80211_rx_h_check and
2584          * ieee80211_rx_h_decrypt. This cleanup may eventually happen, but for
2585          * the time being, the call can be here since RX reorder buf processing
2586          * will implicitly skip duplicates. We could, in theory at least,
2587          * process frames that ieee80211_rx_h_passive_scan would drop (e.g.,
2588          * frames from other than operational channel), but that should not
2589          * happen in normal networks.
2590          */
2591         if (!ieee80211_rx_reorder_ampdu(local, skb, status))
2592                 __ieee80211_rx_handle_packet(hw, skb, status, rate);
2593
2594         rcu_read_unlock();
2595 }
2596 EXPORT_SYMBOL(__ieee80211_rx);
2597
2598 /* This is a version of the rx handler that can be called from hard irq
2599  * context. Post the skb on the queue and schedule the tasklet */
2600 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
2601                           struct ieee80211_rx_status *status)
2602 {
2603         struct ieee80211_local *local = hw_to_local(hw);
2604
2605         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2606
2607         skb->dev = local->mdev;
2608         /* copy status into skb->cb for use by tasklet */
2609         memcpy(skb->cb, status, sizeof(*status));
2610         skb->pkt_type = IEEE80211_RX_MSG;
2611         skb_queue_tail(&local->skb_queue, skb);
2612         tasklet_schedule(&local->tasklet);
2613 }
2614 EXPORT_SYMBOL(ieee80211_rx_irqsafe);