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 "led.h"
  23 #include "mesh.h"
  24 #include "wep.h"
  25 #include "wpa.h"
  26 #include "tkip.h"
  27 #include "wme.h"
  28
  29 u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
  30                                 struct tid_ampdu_rx *tid_agg_rx,
  31                                 struct sk_buff *skb, u16 mpdu_seq_num,
  32                                 int bar_req);
  33 /*
  34  * monitor mode reception
  35  *
  36  * This function cleans up the SKB, i.e. it removes all the stuff
  37  * only useful for monitoring.
  38  */
  39 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
  40                                            struct sk_buff *skb,
  41                                            int rtap_len)
  42 {
  43         skb_pull(skb, rtap_len);
  44
  45         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
  46                 if (likely(skb->len > FCS_LEN))
  47                         skb_trim(skb, skb->len - FCS_LEN);
  48                 else {
  49                         /* driver bug */
  50                         WARN_ON(1);
  51                         dev_kfree_skb(skb);
  52                         skb = NULL;
  53                 }
  54         }
  55
  56         return skb;
  57 }
  58
  59 static inline int should_drop_frame(struct ieee80211_rx_status *status,
  60                                     struct sk_buff *skb,
  61                                     int present_fcs_len,
  62                                     int radiotap_len)
  63 {
  64         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  65
  66         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
  67                 return 1;
  68         if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len))
  69                 return 1;
  70         if (ieee80211_is_ctl(hdr->frame_control) &&
  71             !ieee80211_is_pspoll(hdr->frame_control) &&
  72             !ieee80211_is_back_req(hdr->frame_control))
  73                 return 1;
  74         return 0;
  75 }
  76
  77 static int
  78 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
  79                           struct ieee80211_rx_status *status)
  80 {
  81         int len;
  82
  83         /* always present fields */
  84         len = sizeof(struct ieee80211_radiotap_header) + 9;
  85
  86         if (status->flag & RX_FLAG_TSFT)
  87                 len += 8;
  88         if (local->hw.flags & IEEE80211_HW_SIGNAL_DB ||
  89             local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
  90                 len += 1;
  91         if (local->hw.flags & IEEE80211_HW_NOISE_DBM)
  92                 len += 1;
  93
  94         if (len & 1) /* padding for RX_FLAGS if necessary */
  95                 len++;
  96
  97         /* make sure radiotap starts at a naturally aligned address */
  98         if (len % 8)
  99                 len = roundup(len, 8);
 100
 101         return len;
 102 }
 103
 104 /**
 105  * ieee80211_add_rx_radiotap_header - add radiotap header
 106  *
 107  * add a radiotap header containing all the fields which the hardware provided.
 108  */
 109 static void
 110 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
 111                                  struct sk_buff *skb,
 112                                  struct ieee80211_rx_status *status,
 113                                  struct ieee80211_rate *rate,
 114                                  int rtap_len)
 115 {
 116         struct ieee80211_radiotap_header *rthdr;
 117         unsigned char *pos;
 118
 119         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
 120         memset(rthdr, 0, rtap_len);
 121
 122         /* radiotap header, set always present flags */
 123         rthdr->it_present =
 124                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 125                             (1 << IEEE80211_RADIOTAP_RATE) |
 126                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
 127                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
 128                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
 129         rthdr->it_len = cpu_to_le16(rtap_len);
 130
 131         pos = (unsigned char *)(rthdr+1);
 132
 133         /* the order of the following fields is important */
 134
 135         /* IEEE80211_RADIOTAP_TSFT */
 136         if (status->flag & RX_FLAG_TSFT) {
 137                 *(__le64 *)pos = cpu_to_le64(status->mactime);
 138                 rthdr->it_present |=
 139                         cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
 140                 pos += 8;
 141         }
 142
 143         /* IEEE80211_RADIOTAP_FLAGS */
 144         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 145                 *pos |= IEEE80211_RADIOTAP_F_FCS;
 146         if (status->flag & RX_FLAG_SHORTPRE)
 147                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
 148         pos++;
 149
 150         /* IEEE80211_RADIOTAP_RATE */
 151         *pos = rate->bitrate / 5;
 152         pos++;
 153
 154         /* IEEE80211_RADIOTAP_CHANNEL */
 155         *(__le16 *)pos = cpu_to_le16(status->freq);
 156         pos += 2;
 157         if (status->band == IEEE80211_BAND_5GHZ)
 158                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
 159                                              IEEE80211_CHAN_5GHZ);
 160         else if (rate->flags & IEEE80211_RATE_ERP_G)
 161                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
 162                                              IEEE80211_CHAN_2GHZ);
 163         else
 164                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_CCK |
 165                                              IEEE80211_CHAN_2GHZ);
 166         pos += 2;
 167
 168         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
 169         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
 170                 *pos = status->signal;
 171                 rthdr->it_present |=
 172                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
 173                 pos++;
 174         }
 175
 176         /* IEEE80211_RADIOTAP_DBM_ANTNOISE */
 177         if (local->hw.flags & IEEE80211_HW_NOISE_DBM) {
 178                 *pos = status->noise;
 179                 rthdr->it_present |=
 180                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE);
 181                 pos++;
 182         }
 183
 184         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
 185
 186         /* IEEE80211_RADIOTAP_ANTENNA */
 187         *pos = status->antenna;
 188         pos++;
 189
 190         /* IEEE80211_RADIOTAP_DB_ANTSIGNAL */
 191         if (local->hw.flags & IEEE80211_HW_SIGNAL_DB) {
 192                 *pos = status->signal;
 193                 rthdr->it_present |=
 194                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL);
 195                 pos++;
 196         }
 197
 198         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
 199
 200         /* IEEE80211_RADIOTAP_RX_FLAGS */
 201         /* ensure 2 byte alignment for the 2 byte field as required */
 202         if ((pos - (unsigned char *)rthdr) & 1)
 203                 pos++;
 204         /* FIXME: when radiotap gets a 'bad PLCP' flag use it here */
 205         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 206                 *(__le16 *)pos |= cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS);
 207         pos += 2;
 208 }
 209
 210 /*
 211  * This function copies a received frame to all monitor interfaces and
 212  * returns a cleaned-up SKB that no longer includes the FCS nor the
 213  * radiotap header the driver might have added.
 214  */
 215 static struct sk_buff *
 216 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
 217                      struct ieee80211_rx_status *status,
 218                      struct ieee80211_rate *rate)
 219 {
 220         struct ieee80211_sub_if_data *sdata;
 221         int needed_headroom = 0;
 222         struct sk_buff *skb, *skb2;
 223         struct net_device *prev_dev = NULL;
 224         int present_fcs_len = 0;
 225         int rtap_len = 0;
 226
 227         /*
 228          * First, we may need to make a copy of the skb because
 229          *  (1) we need to modify it for radiotap (if not present), and
 230          *  (2) the other RX handlers will modify the skb we got.
 231          *
 232          * We don't need to, of course, if we aren't going to return
 233          * the SKB because it has a bad FCS/PLCP checksum.
 234          */
 235         if (status->flag & RX_FLAG_RADIOTAP)
 236                 rtap_len = ieee80211_get_radiotap_len(origskb->data);
 237         else
 238                 /* room for the radiotap header based on driver features */
 239                 needed_headroom = ieee80211_rx_radiotap_len(local, status);
 240
 241         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 242                 present_fcs_len = FCS_LEN;
 243
 244         if (!local->monitors) {
 245                 if (should_drop_frame(status, origskb, present_fcs_len,
 246                                       rtap_len)) {
 247                         dev_kfree_skb(origskb);
 248                         return NULL;
 249                 }
 250
 251                 return remove_monitor_info(local, origskb, rtap_len);
 252         }
 253
 254         if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) {
 255                 /* only need to expand headroom if necessary */
 256                 skb = origskb;
 257                 origskb = NULL;
 258
 259                 /*
 260                  * This shouldn't trigger often because most devices have an
 261                  * RX header they pull before we get here, and that should
 262                  * be big enough for our radiotap information. We should
 263                  * probably export the length to drivers so that we can have
 264                  * them allocate enough headroom to start with.
 265                  */
 266                 if (skb_headroom(skb) < needed_headroom &&
 267                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
 268                         dev_kfree_skb(skb);
 269                         return NULL;
 270                 }
 271         } else {
 272                 /*
 273                  * Need to make a copy and possibly remove radiotap header
 274                  * and FCS from the original.
 275                  */
 276                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
 277
 278                 origskb = remove_monitor_info(local, origskb, rtap_len);
 279
 280                 if (!skb)
 281                         return origskb;
 282         }
 283
 284         /* if necessary, prepend radiotap information */
 285         if (!(status->flag & RX_FLAG_RADIOTAP))
 286                 ieee80211_add_rx_radiotap_header(local, skb, status, rate,
 287                                                  needed_headroom);
 288
 289         skb_reset_mac_header(skb);
 290         skb->ip_summed = CHECKSUM_UNNECESSARY;
 291         skb->pkt_type = PACKET_OTHERHOST;
 292         skb->protocol = htons(ETH_P_802_2);
 293
 294         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 295                 if (!netif_running(sdata->dev))
 296                         continue;
 297
 298                 if (sdata->vif.type != IEEE80211_IF_TYPE_MNTR)
 299                         continue;
 300
 301                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
 302                         continue;
 303
 304                 if (prev_dev) {
 305                         skb2 = skb_clone(skb, GFP_ATOMIC);
 306                         if (skb2) {
 307                                 skb2->dev = prev_dev;
 308                                 netif_rx(skb2);
 309                         }
 310                 }
 311
 312                 prev_dev = sdata->dev;
 313                 sdata->dev->stats.rx_packets++;
 314                 sdata->dev->stats.rx_bytes += skb->len;
 315         }
 316
 317         if (prev_dev) {
 318                 skb->dev = prev_dev;
 319                 netif_rx(skb);
 320         } else
 321                 dev_kfree_skb(skb);
 322
 323         return origskb;
 324 }
 325
 326
 327 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
 328 {
 329         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 330         int tid;
 331
 332         /* does the frame have a qos control field? */
 333         if (ieee80211_is_data_qos(hdr->frame_control)) {
 334                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 335                 /* frame has qos control */
 336                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
 337                 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
 338                         rx->flags |= IEEE80211_RX_AMSDU;
 339                 else
 340                         rx->flags &= ~IEEE80211_RX_AMSDU;
 341         } else {
 342                 /*
 343                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
 344                  *
 345                  *      Sequence numbers for management frames, QoS data
 346                  *      frames with a broadcast/multicast address in the
 347                  *      Address 1 field, and all non-QoS data frames sent
 348                  *      by QoS STAs are assigned using an additional single
 349                  *      modulo-4096 counter, [...]
 350                  *
 351                  * We also use that counter for non-QoS STAs.
 352                  */
 353                 tid = NUM_RX_DATA_QUEUES - 1;
 354         }
 355
 356         rx->queue = tid;
 357         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 358          * For now, set skb->priority to 0 for other cases. */
 359         rx->skb->priority = (tid > 7) ? 0 : tid;
 360 }
 361
 362 static void ieee80211_verify_ip_alignment(struct ieee80211_rx_data *rx)
 363 {
 364 #ifdef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
 365         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 366         int hdrlen;
 367
 368         if (!ieee80211_is_data_present(hdr->frame_control))
 369                 return;
 370
 371         /*
 372          * Drivers are required to align the payload data in a way that
 373          * guarantees that the contained IP header is aligned to a four-
 374          * byte boundary. In the case of regular frames, this simply means
 375          * aligning the payload to a four-byte boundary (because either
 376          * the IP header is directly contained, or IV/RFC1042 headers that
 377          * have a length divisible by four are in front of it.
 378          *
 379          * With A-MSDU frames, however, the payload data address must
 380          * yield two modulo four because there are 14-byte 802.3 headers
 381          * within the A-MSDU frames that push the IP header further back
 382          * to a multiple of four again. Thankfully, the specs were sane
 383          * enough this time around to require padding each A-MSDU subframe
 384          * to a length that is a multiple of four.
 385          *
 386          * Padding like atheros hardware adds which is inbetween the 802.11
 387          * header and the payload is not supported, the driver is required
 388          * to move the 802.11 header further back in that case.
 389          */
 390         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 391         if (rx->flags & IEEE80211_RX_AMSDU)
 392                 hdrlen += ETH_HLEN;
 393         WARN_ON_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3);
 394 #endif
 395 }
 396
 397
 398 /* rx handlers */
 399
 400 static ieee80211_rx_result debug_noinline
 401 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
 402 {
 403         struct ieee80211_local *local = rx->local;
 404         struct sk_buff *skb = rx->skb;
 405
 406         if (unlikely(local->sta_hw_scanning))
 407                 return ieee80211_sta_rx_scan(rx->dev, skb, rx->status);
 408
 409         if (unlikely(local->sta_sw_scanning)) {
 410                 /* drop all the other packets during a software scan anyway */
 411                 if (ieee80211_sta_rx_scan(rx->dev, skb, rx->status)
 412                     != RX_QUEUED)
 413                         dev_kfree_skb(skb);
 414                 return RX_QUEUED;
 415         }
 416
 417         if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
 418                 /* scanning finished during invoking of handlers */
 419                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
 420                 return RX_DROP_UNUSABLE;
 421         }
 422
 423         return RX_CONTINUE;
 424 }
 425
 426 static ieee80211_rx_result
 427 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
 428 {
 429         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 430         unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
 431
 432         if (ieee80211_is_data(hdr->frame_control)) {
 433                 if (!ieee80211_has_a4(hdr->frame_control))
 434                         return RX_DROP_MONITOR;
 435                 if (memcmp(hdr->addr4, rx->dev->dev_addr, ETH_ALEN) == 0)
 436                         return RX_DROP_MONITOR;
 437         }
 438
 439         /* If there is not an established peer link and this is not a peer link
 440          * establisment frame, beacon or probe, drop the frame.
 441          */
 442
 443         if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
 444                 struct ieee80211_mgmt *mgmt;
 445
 446                 if (!ieee80211_is_mgmt(hdr->frame_control))
 447                         return RX_DROP_MONITOR;
 448
 449                 if (ieee80211_is_action(hdr->frame_control)) {
 450                         mgmt = (struct ieee80211_mgmt *)hdr;
 451                         if (mgmt->u.action.category != PLINK_CATEGORY)
 452                                 return RX_DROP_MONITOR;
 453                         return RX_CONTINUE;
 454                 }
 455
 456                 if (ieee80211_is_probe_req(hdr->frame_control) ||
 457                     ieee80211_is_probe_resp(hdr->frame_control) ||
 458                     ieee80211_is_beacon(hdr->frame_control))
 459                         return RX_CONTINUE;
 460
 461                 return RX_DROP_MONITOR;
 462
 463         }
 464
 465 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
 466
 467         if (ieee80211_is_data(hdr->frame_control) &&
 468             is_multicast_ether_addr(hdr->addr1) &&
 469             mesh_rmc_check(hdr->addr4, msh_h_get(hdr, hdrlen), rx->dev))
 470                 return RX_DROP_MONITOR;
 471 #undef msh_h_get
 472
 473         return RX_CONTINUE;
 474 }
 475
 476
 477 static ieee80211_rx_result debug_noinline
 478 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
 479 {
 480         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 481
 482         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 483         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 484                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
 485                              rx->sta->last_seq_ctrl[rx->queue] ==
 486                              hdr->seq_ctrl)) {
 487                         if (rx->flags & IEEE80211_RX_RA_MATCH) {
 488                                 rx->local->dot11FrameDuplicateCount++;
 489                                 rx->sta->num_duplicates++;
 490                         }
 491                         return RX_DROP_MONITOR;
 492                 } else
 493                         rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
 494         }
 495
 496         if (unlikely(rx->skb->len < 16)) {
 497                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 498                 return RX_DROP_MONITOR;
 499         }
 500
 501         /* Drop disallowed frame classes based on STA auth/assoc state;
 502          * IEEE 802.11, Chap 5.5.
 503          *
 504          * 80211.o does filtering only based on association state, i.e., it
 505          * drops Class 3 frames from not associated stations. hostapd sends
 506          * deauth/disassoc frames when needed. In addition, hostapd is
 507          * responsible for filtering on both auth and assoc states.
 508          */
 509
 510         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
 511                 return ieee80211_rx_mesh_check(rx);
 512
 513         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
 514                       ieee80211_is_pspoll(hdr->frame_control)) &&
 515                      rx->sdata->vif.type != IEEE80211_IF_TYPE_IBSS &&
 516                      (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
 517                 if ((!ieee80211_has_fromds(hdr->frame_control) &&
 518                      !ieee80211_has_tods(hdr->frame_control) &&
 519                      ieee80211_is_data(hdr->frame_control)) ||
 520                     !(rx->flags & IEEE80211_RX_RA_MATCH)) {
 521                         /* Drop IBSS frames and frames for other hosts
 522                          * silently. */
 523                         return RX_DROP_MONITOR;
 524                 }
 525
 526                 return RX_DROP_MONITOR;
 527         }
 528
 529         return RX_CONTINUE;
 530 }
 531
 532
 533 static ieee80211_rx_result debug_noinline
 534 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
 535 {
 536         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 537         int keyidx;
 538         int hdrlen;
 539         ieee80211_rx_result result = RX_DROP_UNUSABLE;
 540         struct ieee80211_key *stakey = NULL;
 541
 542         /*
 543          * Key selection 101
 544          *
 545          * There are three types of keys:
 546          *  - GTK (group keys)
 547          *  - PTK (pairwise keys)
 548          *  - STK (station-to-station pairwise keys)
 549          *
 550          * When selecting a key, we have to distinguish between multicast
 551          * (including broadcast) and unicast frames, the latter can only
 552          * use PTKs and STKs while the former always use GTKs. Unless, of
 553          * course, actual WEP keys ("pre-RSNA") are used, then unicast
 554          * frames can also use key indizes like GTKs. Hence, if we don't
 555          * have a PTK/STK we check the key index for a WEP key.
 556          *
 557          * Note that in a regular BSS, multicast frames are sent by the
 558          * AP only, associated stations unicast the frame to the AP first
 559          * which then multicasts it on their behalf.
 560          *
 561          * There is also a slight problem in IBSS mode: GTKs are negotiated
 562          * with each station, that is something we don't currently handle.
 563          * The spec seems to expect that one negotiates the same key with
 564          * every station but there's no such requirement; VLANs could be
 565          * possible.
 566          */
 567
 568         if (!ieee80211_has_protected(hdr->frame_control))
 569                 return RX_CONTINUE;
 570
 571         /*
 572          * No point in finding a key and decrypting if the frame is neither
 573          * addressed to us nor a multicast frame.
 574          */
 575         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
 576                 return RX_CONTINUE;
 577
 578         if (rx->sta)
 579                 stakey = rcu_dereference(rx->sta->key);
 580
 581         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
 582                 rx->key = stakey;
 583         } else {
 584                 /*
 585                  * The device doesn't give us the IV so we won't be
 586                  * able to look up the key. That's ok though, we
 587                  * don't need to decrypt the frame, we just won't
 588                  * be able to keep statistics accurate.
 589                  * Except for key threshold notifications, should
 590                  * we somehow allow the driver to tell us which key
 591                  * the hardware used if this flag is set?
 592                  */
 593                 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
 594                     (rx->status->flag & RX_FLAG_IV_STRIPPED))
 595                         return RX_CONTINUE;
 596
 597                 hdrlen = ieee80211_hdrlen(hdr->frame_control);
 598
 599                 if (rx->skb->len < 8 + hdrlen)
 600                         return RX_DROP_UNUSABLE; /* TODO: count this? */
 601
 602                 /*
 603                  * no need to call ieee80211_wep_get_keyidx,
 604                  * it verifies a bunch of things we've done already
 605                  */
 606                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
 607
 608                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
 609
 610                 /*
 611                  * RSNA-protected unicast frames should always be sent with
 612                  * pairwise or station-to-station keys, but for WEP we allow
 613                  * using a key index as well.
 614                  */
 615                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
 616                     !is_multicast_ether_addr(hdr->addr1))
 617                         rx->key = NULL;
 618         }
 619
 620         if (rx->key) {
 621                 rx->key->tx_rx_count++;
 622                 /* TODO: add threshold stuff again */
 623         } else {
 624                 return RX_DROP_MONITOR;
 625         }
 626
 627         /* Check for weak IVs if possible */
 628         if (rx->sta && rx->key->conf.alg == ALG_WEP &&
 629             ieee80211_is_data(hdr->frame_control) &&
 630             (!(rx->status->flag & RX_FLAG_IV_STRIPPED) ||
 631              !(rx->status->flag & RX_FLAG_DECRYPTED)) &&
 632             ieee80211_wep_is_weak_iv(rx->skb, rx->key))
 633                 rx->sta->wep_weak_iv_count++;
 634
 635         switch (rx->key->conf.alg) {
 636         case ALG_WEP:
 637                 result = ieee80211_crypto_wep_decrypt(rx);
 638                 break;
 639         case ALG_TKIP:
 640                 result = ieee80211_crypto_tkip_decrypt(rx);
 641                 break;
 642         case ALG_CCMP:
 643                 result = ieee80211_crypto_ccmp_decrypt(rx);
 644                 break;
 645         }
 646
 647         /* either the frame has been decrypted or will be dropped */
 648         rx->status->flag |= RX_FLAG_DECRYPTED;
 649
 650         return result;
 651 }
 652
 653 static void ap_sta_ps_start(struct net_device *dev, struct sta_info *sta)
 654 {
 655         struct ieee80211_sub_if_data *sdata;
 656         DECLARE_MAC_BUF(mac);
 657
 658         sdata = sta->sdata;
 659
 660         atomic_inc(&sdata->bss->num_sta_ps);
 661         set_and_clear_sta_flags(sta, WLAN_STA_PS, WLAN_STA_PSPOLL);
 662 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 663         printk(KERN_DEBUG "%s: STA %s aid %d enters power save mode\n",
 664                dev->name, print_mac(mac, sta->addr), sta->aid);
 665 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 666 }
 667
 668 static int ap_sta_ps_end(struct net_device *dev, struct sta_info *sta)
 669 {
 670         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 671         struct sk_buff *skb;
 672         int sent = 0;
 673         struct ieee80211_sub_if_data *sdata;
 674         struct ieee80211_tx_info *info;
 675         DECLARE_MAC_BUF(mac);
 676
 677         sdata = sta->sdata;
 678
 679         atomic_dec(&sdata->bss->num_sta_ps);
 680
 681         clear_sta_flags(sta, WLAN_STA_PS | WLAN_STA_PSPOLL);
 682
 683         if (!skb_queue_empty(&sta->ps_tx_buf))
 684                 sta_info_clear_tim_bit(sta);
 685
 686 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 687         printk(KERN_DEBUG "%s: STA %s aid %d exits power save mode\n",
 688                dev->name, print_mac(mac, sta->addr), sta->aid);
 689 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 690
 691         /* Send all buffered frames to the station */
 692         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
 693                 info = IEEE80211_SKB_CB(skb);
 694                 sent++;
 695                 info->flags |= IEEE80211_TX_CTL_REQUEUE;
 696                 dev_queue_xmit(skb);
 697         }
 698         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
 699                 info = IEEE80211_SKB_CB(skb);
 700                 local->total_ps_buffered--;
 701                 sent++;
 702 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 703                 printk(KERN_DEBUG "%s: STA %s aid %d send PS frame "
 704                        "since STA not sleeping anymore\n", dev->name,
 705                        print_mac(mac, sta->addr), sta->aid);
 706 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 707                 info->flags |= IEEE80211_TX_CTL_REQUEUE;
 708                 dev_queue_xmit(skb);
 709         }
 710
 711         return sent;
 712 }
 713
 714 static ieee80211_rx_result debug_noinline
 715 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
 716 {
 717         struct sta_info *sta = rx->sta;
 718         struct net_device *dev = rx->dev;
 719         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 720
 721         if (!sta)
 722                 return RX_CONTINUE;
 723
 724         /* Update last_rx only for IBSS packets which are for the current
 725          * BSSID to avoid keeping the current IBSS network alive in cases where
 726          * other STAs are using different BSSID. */
 727         if (rx->sdata->vif.type == IEEE80211_IF_TYPE_IBSS) {
 728                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
 729                                                 IEEE80211_IF_TYPE_IBSS);
 730                 if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0)
 731                         sta->last_rx = jiffies;
 732         } else
 733         if (!is_multicast_ether_addr(hdr->addr1) ||
 734             rx->sdata->vif.type == IEEE80211_IF_TYPE_STA) {
 735                 /* Update last_rx only for unicast frames in order to prevent
 736                  * the Probe Request frames (the only broadcast frames from a
 737                  * STA in infrastructure mode) from keeping a connection alive.
 738                  * Mesh beacons will update last_rx when if they are found to
 739                  * match the current local configuration when processed.
 740                  */
 741                 sta->last_rx = jiffies;
 742         }
 743
 744         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
 745                 return RX_CONTINUE;
 746
 747         sta->rx_fragments++;
 748         sta->rx_bytes += rx->skb->len;
 749         sta->last_signal = rx->status->signal;
 750         sta->last_qual = rx->status->qual;
 751         sta->last_noise = rx->status->noise;
 752
 753         if (!ieee80211_has_morefrags(hdr->frame_control) &&
 754             (rx->sdata->vif.type == IEEE80211_IF_TYPE_AP ||
 755              rx->sdata->vif.type == IEEE80211_IF_TYPE_VLAN)) {
 756                 /* Change STA power saving mode only in the end of a frame
 757                  * exchange sequence */
 758                 if (test_sta_flags(sta, WLAN_STA_PS) &&
 759                     !ieee80211_has_pm(hdr->frame_control))
 760                         rx->sent_ps_buffered += ap_sta_ps_end(dev, sta);
 761                 else if (!test_sta_flags(sta, WLAN_STA_PS) &&
 762                          ieee80211_has_pm(hdr->frame_control))
 763                         ap_sta_ps_start(dev, sta);
 764         }
 765
 766         /* Drop data::nullfunc frames silently, since they are used only to
 767          * control station power saving mode. */
 768         if (ieee80211_is_nullfunc(hdr->frame_control)) {
 769                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
 770                 /* Update counter and free packet here to avoid counting this
 771                  * as a dropped packed. */
 772                 sta->rx_packets++;
 773                 dev_kfree_skb(rx->skb);
 774                 return RX_QUEUED;
 775         }
 776
 777         return RX_CONTINUE;
 778 } /* ieee80211_rx_h_sta_process */
 779
 780 static inline struct ieee80211_fragment_entry *
 781 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
 782                          unsigned int frag, unsigned int seq, int rx_queue,
 783                          struct sk_buff **skb)
 784 {
 785         struct ieee80211_fragment_entry *entry;
 786         int idx;
 787
 788         idx = sdata->fragment_next;
 789         entry = &sdata->fragments[sdata->fragment_next++];
 790         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
 791                 sdata->fragment_next = 0;
 792
 793         if (!skb_queue_empty(&entry->skb_list)) {
 794 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 795                 struct ieee80211_hdr *hdr =
 796                         (struct ieee80211_hdr *) entry->skb_list.next->data;
 797                 DECLARE_MAC_BUF(mac);
 798                 DECLARE_MAC_BUF(mac2);
 799                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
 800                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
 801                        "addr1=%s addr2=%s\n",
 802                        sdata->dev->name, idx,
 803                        jiffies - entry->first_frag_time, entry->seq,
 804                        entry->last_frag, print_mac(mac, hdr->addr1),
 805                        print_mac(mac2, hdr->addr2));
 806 #endif
 807                 __skb_queue_purge(&entry->skb_list);
 808         }
 809
 810         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
 811         *skb = NULL;
 812         entry->first_frag_time = jiffies;
 813         entry->seq = seq;
 814         entry->rx_queue = rx_queue;
 815         entry->last_frag = frag;
 816         entry->ccmp = 0;
 817         entry->extra_len = 0;
 818
 819         return entry;
 820 }
 821
 822 static inline struct ieee80211_fragment_entry *
 823 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
 824                           u16 fc, unsigned int frag, unsigned int seq,
 825                           int rx_queue, struct ieee80211_hdr *hdr)
 826 {
 827         struct ieee80211_fragment_entry *entry;
 828         int i, idx;
 829
 830         idx = sdata->fragment_next;
 831         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
 832                 struct ieee80211_hdr *f_hdr;
 833                 u16 f_fc;
 834
 835                 idx--;
 836                 if (idx < 0)
 837                         idx = IEEE80211_FRAGMENT_MAX - 1;
 838
 839                 entry = &sdata->fragments[idx];
 840                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
 841                     entry->rx_queue != rx_queue ||
 842                     entry->last_frag + 1 != frag)
 843                         continue;
 844
 845                 f_hdr = (struct ieee80211_hdr *) entry->skb_list.next->data;
 846                 f_fc = le16_to_cpu(f_hdr->frame_control);
 847
 848                 if ((fc & IEEE80211_FCTL_FTYPE) != (f_fc & IEEE80211_FCTL_FTYPE) ||
 849                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
 850                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
 851                         continue;
 852
 853                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
 854                         __skb_queue_purge(&entry->skb_list);
 855                         continue;
 856                 }
 857                 return entry;
 858         }
 859
 860         return NULL;
 861 }
 862
 863 static ieee80211_rx_result debug_noinline
 864 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
 865 {
 866         struct ieee80211_hdr *hdr;
 867         u16 sc;
 868         unsigned int frag, seq;
 869         struct ieee80211_fragment_entry *entry;
 870         struct sk_buff *skb;
 871         DECLARE_MAC_BUF(mac);
 872
 873         hdr = (struct ieee80211_hdr *) rx->skb->data;
 874         sc = le16_to_cpu(hdr->seq_ctrl);
 875         frag = sc & IEEE80211_SCTL_FRAG;
 876
 877         if (likely((!(rx->fc & IEEE80211_FCTL_MOREFRAGS) && frag == 0) ||
 878                    (rx->skb)->len < 24 ||
 879                    is_multicast_ether_addr(hdr->addr1))) {
 880                 /* not fragmented */
 881                 goto out;
 882         }
 883         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
 884
 885         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
 886
 887         if (frag == 0) {
 888                 /* This is the first fragment of a new frame. */
 889                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
 890                                                  rx->queue, &(rx->skb));
 891                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
 892                     (rx->fc & IEEE80211_FCTL_PROTECTED)) {
 893                         /* Store CCMP PN so that we can verify that the next
 894                          * fragment has a sequential PN value. */
 895                         entry->ccmp = 1;
 896                         memcpy(entry->last_pn,
 897                                rx->key->u.ccmp.rx_pn[rx->queue],
 898                                CCMP_PN_LEN);
 899                 }
 900                 return RX_QUEUED;
 901         }
 902
 903         /* This is a fragment for a frame that should already be pending in
 904          * fragment cache. Add this fragment to the end of the pending entry.
 905          */
 906         entry = ieee80211_reassemble_find(rx->sdata, rx->fc, frag, seq,
 907                                           rx->queue, hdr);
 908         if (!entry) {
 909                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 910                 return RX_DROP_MONITOR;
 911         }
 912
 913         /* Verify that MPDUs within one MSDU have sequential PN values.
 914          * (IEEE 802.11i, 8.3.3.4.5) */
 915         if (entry->ccmp) {
 916                 int i;
 917                 u8 pn[CCMP_PN_LEN], *rpn;
 918                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
 919                         return RX_DROP_UNUSABLE;
 920                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
 921                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
 922                         pn[i]++;
 923                         if (pn[i])
 924                                 break;
 925                 }
 926                 rpn = rx->key->u.ccmp.rx_pn[rx->queue];
 927                 if (memcmp(pn, rpn, CCMP_PN_LEN))
 928                         return RX_DROP_UNUSABLE;
 929                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
 930         }
 931
 932         skb_pull(rx->skb, ieee80211_get_hdrlen(rx->fc));
 933         __skb_queue_tail(&entry->skb_list, rx->skb);
 934         entry->last_frag = frag;
 935         entry->extra_len += rx->skb->len;
 936         if (rx->fc & IEEE80211_FCTL_MOREFRAGS) {
 937                 rx->skb = NULL;
 938                 return RX_QUEUED;
 939         }
 940
 941         rx->skb = __skb_dequeue(&entry->skb_list);
 942         if (skb_tailroom(rx->skb) < entry->extra_len) {
 943                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
 944                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
 945                                               GFP_ATOMIC))) {
 946                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 947                         __skb_queue_purge(&entry->skb_list);
 948                         return RX_DROP_UNUSABLE;
 949                 }
 950         }
 951         while ((skb = __skb_dequeue(&entry->skb_list))) {
 952                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
 953                 dev_kfree_skb(skb);
 954         }
 955
 956         /* Complete frame has been reassembled - process it now */
 957         rx->flags |= IEEE80211_RX_FRAGMENTED;
 958
 959  out:
 960         if (rx->sta)
 961                 rx->sta->rx_packets++;
 962         if (is_multicast_ether_addr(hdr->addr1))
 963                 rx->local->dot11MulticastReceivedFrameCount++;
 964         else
 965                 ieee80211_led_rx(rx->local);
 966         return RX_CONTINUE;
 967 }
 968
 969 static ieee80211_rx_result debug_noinline
 970 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
 971 {
 972         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
 973         struct sk_buff *skb;
 974         int no_pending_pkts;
 975         DECLARE_MAC_BUF(mac);
 976
 977         if (likely(!rx->sta ||
 978                    (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL ||
 979                    (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PSPOLL ||
 980                    !(rx->flags & IEEE80211_RX_RA_MATCH)))
 981                 return RX_CONTINUE;
 982
 983         if ((sdata->vif.type != IEEE80211_IF_TYPE_AP) &&
 984             (sdata->vif.type != IEEE80211_IF_TYPE_VLAN))
 985                 return RX_DROP_UNUSABLE;
 986
 987         skb = skb_dequeue(&rx->sta->tx_filtered);
 988         if (!skb) {
 989                 skb = skb_dequeue(&rx->sta->ps_tx_buf);
 990                 if (skb)
 991                         rx->local->total_ps_buffered--;
 992         }
 993         no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
 994                 skb_queue_empty(&rx->sta->ps_tx_buf);
 995
 996         if (skb) {
 997                 struct ieee80211_hdr *hdr =
 998                         (struct ieee80211_hdr *) skb->data;
 999
1000                 /*
1001                  * Tell TX path to send one frame even though the STA may
1002                  * still remain is PS mode after this frame exchange.
1003                  */
1004                 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1005
1006 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1007                 printk(KERN_DEBUG "STA %s aid %d: PS Poll (entries after %d)\n",
1008                        print_mac(mac, rx->sta->addr), rx->sta->aid,
1009                        skb_queue_len(&rx->sta->ps_tx_buf));
1010 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1011
1012                 /* Use MoreData flag to indicate whether there are more
1013                  * buffered frames for this STA */
1014                 if (no_pending_pkts)
1015                         hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
1016                 else
1017                         hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1018
1019                 dev_queue_xmit(skb);
1020
1021                 if (no_pending_pkts)
1022                         sta_info_clear_tim_bit(rx->sta);
1023 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1024         } else if (!rx->sent_ps_buffered) {
1025                 /*
1026                  * FIXME: This can be the result of a race condition between
1027                  *        us expiring a frame and the station polling for it.
1028                  *        Should we send it a null-func frame indicating we
1029                  *        have nothing buffered for it?
1030                  */
1031                 printk(KERN_DEBUG "%s: STA %s sent PS Poll even "
1032                        "though there are no buffered frames for it\n",
1033                        rx->dev->name, print_mac(mac, rx->sta->addr));
1034 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1035         }
1036
1037         /* Free PS Poll skb here instead of returning RX_DROP that would
1038          * count as an dropped frame. */
1039         dev_kfree_skb(rx->skb);
1040
1041         return RX_QUEUED;
1042 }
1043
1044 static ieee80211_rx_result debug_noinline
1045 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1046 {
1047         u8 *data = rx->skb->data;
1048         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1049
1050         if (!ieee80211_is_data_qos(hdr->frame_control))
1051                 return RX_CONTINUE;
1052
1053         /* remove the qos control field, update frame type and meta-data */
1054         memmove(data + IEEE80211_QOS_CTL_LEN, data,
1055                 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1056         hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1057         /* change frame type to non QOS */
1058         rx->fc &= ~IEEE80211_STYPE_QOS_DATA;
1059         hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1060
1061         return RX_CONTINUE;
1062 }
1063
1064 static int
1065 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1066 {
1067         if (unlikely(!rx->sta ||
1068             !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1069                 return -EACCES;
1070
1071         return 0;
1072 }
1073
1074 static int
1075 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx)
1076 {
1077         /*
1078          * Pass through unencrypted frames if the hardware has
1079          * decrypted them already.
1080          */
1081         if (rx->status->flag & RX_FLAG_DECRYPTED)
1082                 return 0;
1083
1084         /* Drop unencrypted frames if key is set. */
1085         if (unlikely(!(rx->fc & IEEE80211_FCTL_PROTECTED) &&
1086                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
1087                      (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
1088                      (rx->key || rx->sdata->drop_unencrypted)))
1089                 return -EACCES;
1090
1091         return 0;
1092 }
1093
1094 static int
1095 ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1096 {
1097         struct net_device *dev = rx->dev;
1098         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
1099         u16 fc, hdrlen, ethertype;
1100         u8 *payload;
1101         u8 dst[ETH_ALEN];
1102         u8 src[ETH_ALEN] __aligned(2);
1103         struct sk_buff *skb = rx->skb;
1104         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1105         DECLARE_MAC_BUF(mac);
1106         DECLARE_MAC_BUF(mac2);
1107         DECLARE_MAC_BUF(mac3);
1108         DECLARE_MAC_BUF(mac4);
1109
1110         fc = rx->fc;
1111
1112         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1113                 return -1;
1114
1115         hdrlen = ieee80211_get_hdrlen(fc);
1116
1117         if (ieee80211_vif_is_mesh(&sdata->vif))
1118                 hdrlen += ieee80211_get_mesh_hdrlen(
1119                                 (struct ieee80211s_hdr *) (skb->data + hdrlen));
1120
1121         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
1122          * header
1123          * IEEE 802.11 address fields:
1124          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
1125          *   0     0   DA    SA    BSSID n/a
1126          *   0     1   DA    BSSID SA    n/a
1127          *   1     0   BSSID SA    DA    n/a
1128          *   1     1   RA    TA    DA    SA
1129          */
1130
1131         switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
1132         case IEEE80211_FCTL_TODS:
1133                 /* BSSID SA DA */
1134                 memcpy(dst, hdr->addr3, ETH_ALEN);
1135                 memcpy(src, hdr->addr2, ETH_ALEN);
1136
1137                 if (unlikely(sdata->vif.type != IEEE80211_IF_TYPE_AP &&
1138                              sdata->vif.type != IEEE80211_IF_TYPE_VLAN))
1139                         return -1;
1140                 break;
1141         case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
1142                 /* RA TA DA SA */
1143                 memcpy(dst, hdr->addr3, ETH_ALEN);
1144                 memcpy(src, hdr->addr4, ETH_ALEN);
1145
1146                  if (unlikely(sdata->vif.type != IEEE80211_IF_TYPE_WDS &&
1147                              sdata->vif.type != IEEE80211_IF_TYPE_MESH_POINT))
1148                         return -1;
1149                 break;
1150         case IEEE80211_FCTL_FROMDS:
1151                 /* DA BSSID SA */
1152                 memcpy(dst, hdr->addr1, ETH_ALEN);
1153                 memcpy(src, hdr->addr3, ETH_ALEN);
1154
1155                 if (sdata->vif.type != IEEE80211_IF_TYPE_STA ||
1156                     (is_multicast_ether_addr(dst) &&
1157                      !compare_ether_addr(src, dev->dev_addr)))
1158                         return -1;
1159                 break;
1160         case 0:
1161                 /* DA SA BSSID */
1162                 memcpy(dst, hdr->addr1, ETH_ALEN);
1163                 memcpy(src, hdr->addr2, ETH_ALEN);
1164
1165                 if (sdata->vif.type != IEEE80211_IF_TYPE_IBSS)
1166                         return -1;
1167                 break;
1168         }
1169
1170         if (unlikely(skb->len - hdrlen < 8))
1171                 return -1;
1172
1173         payload = skb->data + hdrlen;
1174         ethertype = (payload[6] << 8) | payload[7];
1175
1176         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1177                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1178                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1179                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1180                  * replace EtherType */
1181                 skb_pull(skb, hdrlen + 6);
1182                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1183                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1184         } else {
1185                 struct ethhdr *ehdr;
1186                 __be16 len;
1187
1188                 skb_pull(skb, hdrlen);
1189                 len = htons(skb->len);
1190                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1191                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1192                 memcpy(ehdr->h_source, src, ETH_ALEN);
1193                 ehdr->h_proto = len;
1194         }
1195         return 0;
1196 }
1197
1198 /*
1199  * requires that rx->skb is a frame with ethernet header
1200  */
1201 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx)
1202 {
1203         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1204                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1205         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1206
1207         /*
1208          * Allow EAPOL frames to us/the PAE group address regardless
1209          * of whether the frame was encrypted or not.
1210          */
1211         if (ehdr->h_proto == htons(ETH_P_PAE) &&
1212             (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
1213              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1214                 return true;
1215
1216         if (ieee80211_802_1x_port_control(rx) ||
1217             ieee80211_drop_unencrypted(rx))
1218                 return false;
1219
1220         return true;
1221 }
1222
1223 /*
1224  * requires that rx->skb is a frame with ethernet header
1225  */
1226 static void
1227 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1228 {
1229         struct net_device *dev = rx->dev;
1230         struct ieee80211_local *local = rx->local;
1231         struct sk_buff *skb, *xmit_skb;
1232         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1233         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1234         struct sta_info *dsta;
1235
1236         skb = rx->skb;
1237         xmit_skb = NULL;
1238
1239         if (local->bridge_packets && (sdata->vif.type == IEEE80211_IF_TYPE_AP ||
1240                                       sdata->vif.type == IEEE80211_IF_TYPE_VLAN) &&
1241             (rx->flags & IEEE80211_RX_RA_MATCH)) {
1242                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1243                         /*
1244                          * send multicast frames both to higher layers in
1245                          * local net stack and back to the wireless medium
1246                          */
1247                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1248                         if (!xmit_skb && net_ratelimit())
1249                                 printk(KERN_DEBUG "%s: failed to clone "
1250                                        "multicast frame\n", dev->name);
1251                 } else {
1252                         dsta = sta_info_get(local, skb->data);
1253                         if (dsta && dsta->sdata->dev == dev) {
1254                                 /*
1255                                  * The destination station is associated to
1256                                  * this AP (in this VLAN), so send the frame
1257                                  * directly to it and do not pass it to local
1258                                  * net stack.
1259                                  */
1260                                 xmit_skb = skb;
1261                                 skb = NULL;
1262                         }
1263                 }
1264         }
1265
1266         if (skb) {
1267                 /* deliver to local stack */
1268                 skb->protocol = eth_type_trans(skb, dev);
1269                 memset(skb->cb, 0, sizeof(skb->cb));
1270                 netif_rx(skb);
1271         }
1272
1273         if (xmit_skb) {
1274                 /* send to wireless media */
1275                 xmit_skb->protocol = htons(ETH_P_802_3);
1276                 skb_reset_network_header(xmit_skb);
1277                 skb_reset_mac_header(xmit_skb);
1278                 dev_queue_xmit(xmit_skb);
1279         }
1280 }
1281
1282 static ieee80211_rx_result debug_noinline
1283 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1284 {
1285         struct net_device *dev = rx->dev;
1286         struct ieee80211_local *local = rx->local;
1287         u16 fc, ethertype;
1288         u8 *payload;
1289         struct sk_buff *skb = rx->skb, *frame = NULL;
1290         const struct ethhdr *eth;
1291         int remaining, err;
1292         u8 dst[ETH_ALEN];
1293         u8 src[ETH_ALEN];
1294         DECLARE_MAC_BUF(mac);
1295
1296         fc = rx->fc;
1297         if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
1298                 return RX_CONTINUE;
1299
1300         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1301                 return RX_DROP_MONITOR;
1302
1303         if (!(rx->flags & IEEE80211_RX_AMSDU))
1304                 return RX_CONTINUE;
1305
1306         err = ieee80211_data_to_8023(rx);
1307         if (unlikely(err))
1308                 return RX_DROP_UNUSABLE;
1309
1310         skb->dev = dev;
1311
1312         dev->stats.rx_packets++;
1313         dev->stats.rx_bytes += skb->len;
1314
1315         /* skip the wrapping header */
1316         eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
1317         if (!eth)
1318                 return RX_DROP_UNUSABLE;
1319
1320         while (skb != frame) {
1321                 u8 padding;
1322                 __be16 len = eth->h_proto;
1323                 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
1324
1325                 remaining = skb->len;
1326                 memcpy(dst, eth->h_dest, ETH_ALEN);
1327                 memcpy(src, eth->h_source, ETH_ALEN);
1328
1329                 padding = ((4 - subframe_len) & 0x3);
1330                 /* the last MSDU has no padding */
1331                 if (subframe_len > remaining)
1332                         return RX_DROP_UNUSABLE;
1333
1334                 skb_pull(skb, sizeof(struct ethhdr));
1335                 /* if last subframe reuse skb */
1336                 if (remaining <= subframe_len + padding)
1337                         frame = skb;
1338                 else {
1339                         frame = dev_alloc_skb(local->hw.extra_tx_headroom +
1340                                               subframe_len);
1341
1342                         if (frame == NULL)
1343                                 return RX_DROP_UNUSABLE;
1344
1345                         skb_reserve(frame, local->hw.extra_tx_headroom +
1346                                     sizeof(struct ethhdr));
1347                         memcpy(skb_put(frame, ntohs(len)), skb->data,
1348                                 ntohs(len));
1349
1350                         eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
1351                                                         padding);
1352                         if (!eth) {
1353                                 dev_kfree_skb(frame);
1354                                 return RX_DROP_UNUSABLE;
1355                         }
1356                 }
1357
1358                 skb_reset_network_header(frame);
1359                 frame->dev = dev;
1360                 frame->priority = skb->priority;
1361                 rx->skb = frame;
1362
1363                 payload = frame->data;
1364                 ethertype = (payload[6] << 8) | payload[7];
1365
1366                 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1367                             ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1368                            compare_ether_addr(payload,
1369                                               bridge_tunnel_header) == 0)) {
1370                         /* remove RFC1042 or Bridge-Tunnel
1371                          * encapsulation and replace EtherType */
1372                         skb_pull(frame, 6);
1373                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1374                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1375                 } else {
1376                         memcpy(skb_push(frame, sizeof(__be16)),
1377                                &len, sizeof(__be16));
1378                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1379                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1380                 }
1381
1382                 if (!ieee80211_frame_allowed(rx)) {
1383                         if (skb == frame) /* last frame */
1384                                 return RX_DROP_UNUSABLE;
1385                         dev_kfree_skb(frame);
1386                         continue;
1387                 }
1388
1389                 ieee80211_deliver_skb(rx);
1390         }
1391
1392         return RX_QUEUED;
1393 }
1394
1395 static ieee80211_rx_result debug_noinline
1396 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1397 {
1398         struct ieee80211_hdr *hdr;
1399         struct ieee80211s_hdr *mesh_hdr;
1400         unsigned int hdrlen;
1401         struct sk_buff *skb = rx->skb, *fwd_skb;
1402
1403         hdr = (struct ieee80211_hdr *) skb->data;
1404         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1405         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1406
1407         if (!ieee80211_is_data(hdr->frame_control))
1408                 return RX_CONTINUE;
1409
1410         if (!mesh_hdr->ttl)
1411                 /* illegal frame */
1412                 return RX_DROP_MONITOR;
1413
1414         if (compare_ether_addr(rx->dev->dev_addr, hdr->addr3) == 0)
1415                 return RX_CONTINUE;
1416
1417         mesh_hdr->ttl--;
1418
1419         if (rx->flags & IEEE80211_RX_RA_MATCH) {
1420                 if (!mesh_hdr->ttl)
1421                         IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.sta,
1422                                                      dropped_frames_ttl);
1423                 else {
1424                         struct ieee80211_hdr *fwd_hdr;
1425                         fwd_skb = skb_copy(skb, GFP_ATOMIC);
1426
1427                         if (!fwd_skb && net_ratelimit())
1428                                 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1429                                                    rx->dev->name);
1430
1431                         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1432                         /*
1433                          * Save TA to addr1 to send TA a path error if a
1434                          * suitable next hop is not found
1435                          */
1436                         memcpy(fwd_hdr->addr1, fwd_hdr->addr2, ETH_ALEN);
1437                         memcpy(fwd_hdr->addr2, rx->dev->dev_addr, ETH_ALEN);
1438                         fwd_skb->dev = rx->local->mdev;
1439                         fwd_skb->iif = rx->dev->ifindex;
1440                         dev_queue_xmit(fwd_skb);
1441                 }
1442         }
1443
1444         if (is_multicast_ether_addr(hdr->addr3) ||
1445             rx->dev->flags & IFF_PROMISC)
1446                 return RX_CONTINUE;
1447         else
1448                 return RX_DROP_MONITOR;
1449 }
1450
1451
1452 static ieee80211_rx_result debug_noinline
1453 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1454 {
1455         struct net_device *dev = rx->dev;
1456         u16 fc;
1457         int err;
1458
1459         fc = rx->fc;
1460         if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
1461                 return RX_CONTINUE;
1462
1463         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1464                 return RX_DROP_MONITOR;
1465
1466         err = ieee80211_data_to_8023(rx);
1467         if (unlikely(err))
1468                 return RX_DROP_UNUSABLE;
1469
1470         if (!ieee80211_frame_allowed(rx))
1471                 return RX_DROP_MONITOR;
1472
1473         rx->skb->dev = dev;
1474
1475         dev->stats.rx_packets++;
1476         dev->stats.rx_bytes += rx->skb->len;
1477
1478         ieee80211_deliver_skb(rx);
1479
1480         return RX_QUEUED;
1481 }
1482
1483 static ieee80211_rx_result debug_noinline
1484 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
1485 {
1486         struct ieee80211_local *local = rx->local;
1487         struct ieee80211_hw *hw = &local->hw;
1488         struct sk_buff *skb = rx->skb;
1489         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1490         struct tid_ampdu_rx *tid_agg_rx;
1491         u16 start_seq_num;
1492         u16 tid;
1493
1494         if (likely(!ieee80211_is_ctl(bar->frame_control)))
1495                 return RX_CONTINUE;
1496
1497         if (ieee80211_is_back_req(bar->frame_control)) {
1498                 if (!rx->sta)
1499                         return RX_CONTINUE;
1500                 tid = le16_to_cpu(bar->control) >> 12;
1501                 if (rx->sta->ampdu_mlme.tid_state_rx[tid]
1502                                         != HT_AGG_STATE_OPERATIONAL)
1503                         return RX_CONTINUE;
1504                 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid];
1505
1506                 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1507
1508                 /* reset session timer */
1509                 if (tid_agg_rx->timeout) {
1510                         unsigned long expires =
1511                                 jiffies + (tid_agg_rx->timeout / 1000) * HZ;
1512                         mod_timer(&tid_agg_rx->session_timer, expires);
1513                 }
1514
1515                 /* manage reordering buffer according to requested */
1516                 /* sequence number */
1517                 rcu_read_lock();
1518                 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL,
1519                                                  start_seq_num, 1);
1520                 rcu_read_unlock();
1521                 return RX_DROP_UNUSABLE;
1522         }
1523
1524         return RX_CONTINUE;
1525 }
1526
1527 static ieee80211_rx_result debug_noinline
1528 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
1529 {
1530         struct ieee80211_sub_if_data *sdata;
1531
1532         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1533                 return RX_DROP_MONITOR;
1534
1535         sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1536         if ((sdata->vif.type == IEEE80211_IF_TYPE_STA ||
1537              sdata->vif.type == IEEE80211_IF_TYPE_IBSS ||
1538              sdata->vif.type == IEEE80211_IF_TYPE_MESH_POINT) &&
1539             !(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME))
1540                 ieee80211_sta_rx_mgmt(rx->dev, rx->skb, rx->status);
1541         else
1542                 return RX_DROP_MONITOR;
1543
1544         return RX_QUEUED;
1545 }
1546
1547 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1548                                             struct ieee80211_hdr *hdr,
1549                                             struct ieee80211_rx_data *rx)
1550 {
1551         int keyidx;
1552         unsigned int hdrlen;
1553         DECLARE_MAC_BUF(mac);
1554         DECLARE_MAC_BUF(mac2);
1555
1556         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1557         if (rx->skb->len >= hdrlen + 4)
1558                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1559         else
1560                 keyidx = -1;
1561
1562         if (!rx->sta) {
1563                 /*
1564                  * Some hardware seem to generate incorrect Michael MIC
1565                  * reports; ignore them to avoid triggering countermeasures.
1566                  */
1567                 goto ignore;
1568         }
1569
1570         if (!ieee80211_has_protected(hdr->frame_control))
1571                 goto ignore;
1572
1573         if (rx->sdata->vif.type == IEEE80211_IF_TYPE_AP && keyidx) {
1574                 /*
1575                  * APs with pairwise keys should never receive Michael MIC
1576                  * errors for non-zero keyidx because these are reserved for
1577                  * group keys and only the AP is sending real multicast
1578                  * frames in the BSS.
1579                  */
1580                 goto ignore;
1581         }
1582
1583         if (!ieee80211_is_data(hdr->frame_control) &&
1584             !ieee80211_is_auth(hdr->frame_control))
1585                 goto ignore;
1586
1587         mac80211_ev_michael_mic_failure(rx->dev, keyidx, hdr);
1588  ignore:
1589         dev_kfree_skb(rx->skb);
1590         rx->skb = NULL;
1591 }
1592
1593 /* TODO: use IEEE80211_RX_FRAGMENTED */
1594 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx)
1595 {
1596         struct ieee80211_sub_if_data *sdata;
1597         struct ieee80211_local *local = rx->local;
1598         struct ieee80211_rtap_hdr {
1599                 struct ieee80211_radiotap_header hdr;
1600                 u8 flags;
1601                 u8 rate;
1602                 __le16 chan_freq;
1603                 __le16 chan_flags;
1604         } __attribute__ ((packed)) *rthdr;
1605         struct sk_buff *skb = rx->skb, *skb2;
1606         struct net_device *prev_dev = NULL;
1607         struct ieee80211_rx_status *status = rx->status;
1608
1609         if (rx->flags & IEEE80211_RX_CMNTR_REPORTED)
1610                 goto out_free_skb;
1611
1612         if (skb_headroom(skb) < sizeof(*rthdr) &&
1613             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
1614                 goto out_free_skb;
1615
1616         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
1617         memset(rthdr, 0, sizeof(*rthdr));
1618         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
1619         rthdr->hdr.it_present =
1620                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
1621                             (1 << IEEE80211_RADIOTAP_RATE) |
1622                             (1 << IEEE80211_RADIOTAP_CHANNEL));
1623
1624         rthdr->rate = rx->rate->bitrate / 5;
1625         rthdr->chan_freq = cpu_to_le16(status->freq);
1626
1627         if (status->band == IEEE80211_BAND_5GHZ)
1628                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
1629                                                 IEEE80211_CHAN_5GHZ);
1630         else
1631                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
1632                                                 IEEE80211_CHAN_2GHZ);
1633
1634         skb_set_mac_header(skb, 0);
1635         skb->ip_summed = CHECKSUM_UNNECESSARY;
1636         skb->pkt_type = PACKET_OTHERHOST;
1637         skb->protocol = htons(ETH_P_802_2);
1638
1639         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1640                 if (!netif_running(sdata->dev))
1641                         continue;
1642
1643                 if (sdata->vif.type != IEEE80211_IF_TYPE_MNTR ||
1644                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
1645                         continue;
1646
1647                 if (prev_dev) {
1648                         skb2 = skb_clone(skb, GFP_ATOMIC);
1649                         if (skb2) {
1650                                 skb2->dev = prev_dev;
1651                                 netif_rx(skb2);
1652                         }
1653                 }
1654
1655                 prev_dev = sdata->dev;
1656                 sdata->dev->stats.rx_packets++;
1657                 sdata->dev->stats.rx_bytes += skb->len;
1658         }
1659
1660         if (prev_dev) {
1661                 skb->dev = prev_dev;
1662                 netif_rx(skb);
1663                 skb = NULL;
1664         } else
1665                 goto out_free_skb;
1666
1667         rx->flags |= IEEE80211_RX_CMNTR_REPORTED;
1668         return;
1669
1670  out_free_skb:
1671         dev_kfree_skb(skb);
1672 }
1673
1674
1675 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
1676                                          struct ieee80211_rx_data *rx,
1677                                          struct sk_buff *skb)
1678 {
1679         ieee80211_rx_result res = RX_DROP_MONITOR;
1680
1681         rx->skb = skb;
1682         rx->sdata = sdata;
1683         rx->dev = sdata->dev;
1684
1685 #define CALL_RXH(rxh)                   \
1686         do {                            \
1687                 res = rxh(rx);          \
1688                 if (res != RX_CONTINUE) \
1689                         goto rxh_done;  \
1690         } while (0);
1691
1692         CALL_RXH(ieee80211_rx_h_passive_scan)
1693         CALL_RXH(ieee80211_rx_h_check)
1694         CALL_RXH(ieee80211_rx_h_decrypt)
1695         CALL_RXH(ieee80211_rx_h_sta_process)
1696         CALL_RXH(ieee80211_rx_h_defragment)
1697         CALL_RXH(ieee80211_rx_h_ps_poll)
1698         CALL_RXH(ieee80211_rx_h_michael_mic_verify)
1699         /* must be after MMIC verify so header is counted in MPDU mic */
1700         CALL_RXH(ieee80211_rx_h_remove_qos_control)
1701         CALL_RXH(ieee80211_rx_h_amsdu)
1702         if (ieee80211_vif_is_mesh(&sdata->vif))
1703                 CALL_RXH(ieee80211_rx_h_mesh_fwding);
1704         CALL_RXH(ieee80211_rx_h_data)
1705         CALL_RXH(ieee80211_rx_h_ctrl)
1706         CALL_RXH(ieee80211_rx_h_mgmt)
1707
1708 #undef CALL_RXH
1709
1710  rxh_done:
1711         switch (res) {
1712         case RX_DROP_MONITOR:
1713                 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
1714                 if (rx->sta)
1715                         rx->sta->rx_dropped++;
1716                 /* fall through */
1717         case RX_CONTINUE:
1718                 ieee80211_rx_cooked_monitor(rx);
1719                 break;
1720         case RX_DROP_UNUSABLE:
1721                 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
1722                 if (rx->sta)
1723                         rx->sta->rx_dropped++;
1724                 dev_kfree_skb(rx->skb);
1725                 break;
1726         case RX_QUEUED:
1727                 I802_DEBUG_INC(sdata->local->rx_handlers_queued);
1728                 break;
1729         }
1730 }
1731
1732 /* main receive path */
1733
1734 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
1735                                 u8 *bssid, struct ieee80211_rx_data *rx,
1736                                 struct ieee80211_hdr *hdr)
1737 {
1738         int multicast = is_multicast_ether_addr(hdr->addr1);
1739
1740         switch (sdata->vif.type) {
1741         case IEEE80211_IF_TYPE_STA:
1742                 if (!bssid)
1743                         return 0;
1744                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1745                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
1746                                 return 0;
1747                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1748                 } else if (!multicast &&
1749                            compare_ether_addr(sdata->dev->dev_addr,
1750                                               hdr->addr1) != 0) {
1751                         if (!(sdata->dev->flags & IFF_PROMISC))
1752                                 return 0;
1753                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1754                 }
1755                 break;
1756         case IEEE80211_IF_TYPE_IBSS:
1757                 if (!bssid)
1758                         return 0;
1759                 if (ieee80211_is_beacon(hdr->frame_control)) {
1760                         if (!rx->sta)
1761                                 rx->sta = ieee80211_ibss_add_sta(sdata->dev,
1762                                                 rx->skb, bssid, hdr->addr2,
1763                                                 BIT(rx->status->rate_idx));
1764                         return 1;
1765                 }
1766                 else if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1767                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
1768                                 return 0;
1769                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1770                 } else if (!multicast &&
1771                            compare_ether_addr(sdata->dev->dev_addr,
1772                                               hdr->addr1) != 0) {
1773                         if (!(sdata->dev->flags & IFF_PROMISC))
1774                                 return 0;
1775                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1776                 } else if (!rx->sta)
1777                         rx->sta = ieee80211_ibss_add_sta(sdata->dev, rx->skb,
1778                                                 bssid, hdr->addr2,
1779                                                 BIT(rx->status->rate_idx));
1780                 break;
1781         case IEEE80211_IF_TYPE_MESH_POINT:
1782                 if (!multicast &&
1783                     compare_ether_addr(sdata->dev->dev_addr,
1784                                        hdr->addr1) != 0) {
1785                         if (!(sdata->dev->flags & IFF_PROMISC))
1786                                 return 0;
1787
1788                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1789                 }
1790                 break;
1791         case IEEE80211_IF_TYPE_VLAN:
1792         case IEEE80211_IF_TYPE_AP:
1793                 if (!bssid) {
1794                         if (compare_ether_addr(sdata->dev->dev_addr,
1795                                                hdr->addr1))
1796                                 return 0;
1797                 } else if (!ieee80211_bssid_match(bssid,
1798                                         sdata->dev->dev_addr)) {
1799                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
1800                                 return 0;
1801                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1802                 }
1803                 break;
1804         case IEEE80211_IF_TYPE_WDS:
1805                 if (bssid || !ieee80211_is_data(hdr->frame_control))
1806                         return 0;
1807                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
1808                         return 0;
1809                 break;
1810         case IEEE80211_IF_TYPE_MNTR:
1811                 /* take everything */
1812                 break;
1813         case IEEE80211_IF_TYPE_INVALID:
1814                 /* should never get here */
1815                 WARN_ON(1);
1816                 break;
1817         }
1818
1819         return 1;
1820 }
1821
1822 /*
1823  * This is the actual Rx frames handler. as it blongs to Rx path it must
1824  * be called with rcu_read_lock protection.
1825  */
1826 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
1827                                          struct sk_buff *skb,
1828                                          struct ieee80211_rx_status *status,
1829                                          struct ieee80211_rate *rate)
1830 {
1831         struct ieee80211_local *local = hw_to_local(hw);
1832         struct ieee80211_sub_if_data *sdata;
1833         struct ieee80211_hdr *hdr;
1834         struct ieee80211_rx_data rx;
1835         u16 type;
1836         int prepares;
1837         struct ieee80211_sub_if_data *prev = NULL;
1838         struct sk_buff *skb_new;
1839         u8 *bssid;
1840
1841         hdr = (struct ieee80211_hdr *) skb->data;
1842         memset(&rx, 0, sizeof(rx));
1843         rx.skb = skb;
1844         rx.local = local;
1845
1846         rx.status = status;
1847         rx.rate = rate;
1848         rx.fc = le16_to_cpu(hdr->frame_control);
1849         type = rx.fc & IEEE80211_FCTL_FTYPE;
1850
1851         if (type == IEEE80211_FTYPE_DATA || type == IEEE80211_FTYPE_MGMT)
1852                 local->dot11ReceivedFragmentCount++;
1853
1854         rx.sta = sta_info_get(local, hdr->addr2);
1855         if (rx.sta) {
1856                 rx.sdata = rx.sta->sdata;
1857                 rx.dev = rx.sta->sdata->dev;
1858         }
1859
1860         if ((status->flag & RX_FLAG_MMIC_ERROR)) {
1861                 ieee80211_rx_michael_mic_report(local->mdev, hdr, &rx);
1862                 return;
1863         }
1864
1865         if (unlikely(local->sta_sw_scanning || local->sta_hw_scanning))
1866                 rx.flags |= IEEE80211_RX_IN_SCAN;
1867
1868         ieee80211_parse_qos(&rx);
1869         ieee80211_verify_ip_alignment(&rx);
1870
1871         skb = rx.skb;
1872
1873         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1874                 if (!netif_running(sdata->dev))
1875                         continue;
1876
1877                 if (sdata->vif.type == IEEE80211_IF_TYPE_MNTR)
1878                         continue;
1879
1880                 bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
1881                 rx.flags |= IEEE80211_RX_RA_MATCH;
1882                 prepares = prepare_for_handlers(sdata, bssid, &rx, hdr);
1883
1884                 if (!prepares)
1885                         continue;
1886
1887                 /*
1888                  * frame is destined for this interface, but if it's not
1889                  * also for the previous one we handle that after the
1890                  * loop to avoid copying the SKB once too much
1891                  */
1892
1893                 if (!prev) {
1894                         prev = sdata;
1895                         continue;
1896                 }
1897
1898                 /*
1899                  * frame was destined for the previous interface
1900                  * so invoke RX handlers for it
1901                  */
1902
1903                 skb_new = skb_copy(skb, GFP_ATOMIC);
1904                 if (!skb_new) {
1905                         if (net_ratelimit())
1906                                 printk(KERN_DEBUG "%s: failed to copy "
1907                                        "multicast frame for %s\n",
1908                                        wiphy_name(local->hw.wiphy),
1909                                        prev->dev->name);
1910                         continue;
1911                 }
1912                 rx.fc = le16_to_cpu(hdr->frame_control);
1913                 ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
1914                 prev = sdata;
1915         }
1916         if (prev) {
1917                 rx.fc = le16_to_cpu(hdr->frame_control);
1918                 ieee80211_invoke_rx_handlers(prev, &rx, skb);
1919         } else
1920                 dev_kfree_skb(skb);
1921 }
1922
1923 #define SEQ_MODULO 0x1000
1924 #define SEQ_MASK   0xfff
1925
1926 static inline int seq_less(u16 sq1, u16 sq2)
1927 {
1928         return (((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1));
1929 }
1930
1931 static inline u16 seq_inc(u16 sq)
1932 {
1933         return ((sq + 1) & SEQ_MASK);
1934 }
1935
1936 static inline u16 seq_sub(u16 sq1, u16 sq2)
1937 {
1938         return ((sq1 - sq2) & SEQ_MASK);
1939 }
1940
1941
1942 /*
1943  * As it function blongs to Rx path it must be called with
1944  * the proper rcu_read_lock protection for its flow.
1945  */
1946 u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
1947                                 struct tid_ampdu_rx *tid_agg_rx,
1948                                 struct sk_buff *skb, u16 mpdu_seq_num,
1949                                 int bar_req)
1950 {
1951         struct ieee80211_local *local = hw_to_local(hw);
1952         struct ieee80211_rx_status status;
1953         u16 head_seq_num, buf_size;
1954         int index;
1955         struct ieee80211_supported_band *sband;
1956         struct ieee80211_rate *rate;
1957
1958         buf_size = tid_agg_rx->buf_size;
1959         head_seq_num = tid_agg_rx->head_seq_num;
1960
1961         /* frame with out of date sequence number */
1962         if (seq_less(mpdu_seq_num, head_seq_num)) {
1963                 dev_kfree_skb(skb);
1964                 return 1;
1965         }
1966
1967         /* if frame sequence number exceeds our buffering window size or
1968          * block Ack Request arrived - release stored frames */
1969         if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
1970                 /* new head to the ordering buffer */
1971                 if (bar_req)
1972                         head_seq_num = mpdu_seq_num;
1973                 else
1974                         head_seq_num =
1975                                 seq_inc(seq_sub(mpdu_seq_num, buf_size));
1976                 /* release stored frames up to new head to stack */
1977                 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
1978                         index = seq_sub(tid_agg_rx->head_seq_num,
1979                                 tid_agg_rx->ssn)
1980                                 % tid_agg_rx->buf_size;
1981
1982                         if (tid_agg_rx->reorder_buf[index]) {
1983                                 /* release the reordered frames to stack */
1984                                 memcpy(&status,
1985                                         tid_agg_rx->reorder_buf[index]->cb,
1986                                         sizeof(status));
1987                                 sband = local->hw.wiphy->bands[status.band];
1988                                 rate = &sband->bitrates[status.rate_idx];
1989                                 __ieee80211_rx_handle_packet(hw,
1990                                         tid_agg_rx->reorder_buf[index],
1991                                         &status, rate);
1992                                 tid_agg_rx->stored_mpdu_num--;
1993                                 tid_agg_rx->reorder_buf[index] = NULL;
1994                         }
1995                         tid_agg_rx->head_seq_num =
1996                                 seq_inc(tid_agg_rx->head_seq_num);
1997                 }
1998                 if (bar_req)
1999                         return 1;
2000         }
2001
2002         /* now the new frame is always in the range of the reordering */
2003         /* buffer window */
2004         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
2005                                 % tid_agg_rx->buf_size;
2006         /* check if we already stored this frame */
2007         if (tid_agg_rx->reorder_buf[index]) {
2008                 dev_kfree_skb(skb);
2009                 return 1;
2010         }
2011
2012         /* if arrived mpdu is in the right order and nothing else stored */
2013         /* release it immediately */
2014         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
2015                         tid_agg_rx->stored_mpdu_num == 0) {
2016                 tid_agg_rx->head_seq_num =
2017                         seq_inc(tid_agg_rx->head_seq_num);
2018                 return 0;
2019         }
2020
2021         /* put the frame in the reordering buffer */
2022         tid_agg_rx->reorder_buf[index] = skb;
2023         tid_agg_rx->stored_mpdu_num++;
2024         /* release the buffer until next missing frame */
2025         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
2026                                                 % tid_agg_rx->buf_size;
2027         while (tid_agg_rx->reorder_buf[index]) {
2028                 /* release the reordered frame back to stack */
2029                 memcpy(&status, tid_agg_rx->reorder_buf[index]->cb,
2030                         sizeof(status));
2031                 sband = local->hw.wiphy->bands[status.band];
2032                 rate = &sband->bitrates[status.rate_idx];
2033                 __ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index],
2034                                              &status, rate);
2035                 tid_agg_rx->stored_mpdu_num--;
2036                 tid_agg_rx->reorder_buf[index] = NULL;
2037                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
2038                 index = seq_sub(tid_agg_rx->head_seq_num,
2039                         tid_agg_rx->ssn) % tid_agg_rx->buf_size;
2040         }
2041         return 1;
2042 }
2043
2044 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
2045                                      struct sk_buff *skb)
2046 {
2047         struct ieee80211_hw *hw = &local->hw;
2048         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
2049         struct sta_info *sta;
2050         struct tid_ampdu_rx *tid_agg_rx;
2051         u16 sc;
2052         u16 mpdu_seq_num;
2053         u8 ret = 0;
2054         int tid;
2055
2056         sta = sta_info_get(local, hdr->addr2);
2057         if (!sta)
2058                 return ret;
2059
2060         /* filter the QoS data rx stream according to
2061          * STA/TID and check if this STA/TID is on aggregation */
2062         if (!ieee80211_is_data_qos(hdr->frame_control))
2063                 goto end_reorder;
2064
2065         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
2066
2067         if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
2068                 goto end_reorder;
2069
2070         tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
2071
2072         /* qos null data frames are excluded */
2073         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
2074                 goto end_reorder;
2075
2076         /* new un-ordered ampdu frame - process it */
2077
2078         /* reset session timer */
2079         if (tid_agg_rx->timeout) {
2080                 unsigned long expires =
2081                         jiffies + (tid_agg_rx->timeout / 1000) * HZ;
2082                 mod_timer(&tid_agg_rx->session_timer, expires);
2083         }
2084
2085         /* if this mpdu is fragmented - terminate rx aggregation session */
2086         sc = le16_to_cpu(hdr->seq_ctrl);
2087         if (sc & IEEE80211_SCTL_FRAG) {
2088                 ieee80211_sta_stop_rx_ba_session(sta->sdata->dev, sta->addr,
2089                         tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
2090                 ret = 1;
2091                 goto end_reorder;
2092         }
2093
2094         /* according to mpdu sequence number deal with reordering buffer */
2095         mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
2096         ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb,
2097                                                 mpdu_seq_num, 0);
2098  end_reorder:
2099         return ret;
2100 }
2101
2102 /*
2103  * This is the receive path handler. It is called by a low level driver when an
2104  * 802.11 MPDU is received from the hardware.
2105  */
2106 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
2107                     struct ieee80211_rx_status *status)
2108 {
2109         struct ieee80211_local *local = hw_to_local(hw);
2110         struct ieee80211_rate *rate = NULL;
2111         struct ieee80211_supported_band *sband;
2112
2113         if (status->band < 0 ||
2114             status->band >= IEEE80211_NUM_BANDS) {
2115                 WARN_ON(1);
2116                 return;
2117         }
2118
2119         sband = local->hw.wiphy->bands[status->band];
2120
2121         if (!sband ||
2122             status->rate_idx < 0 ||
2123             status->rate_idx >= sband->n_bitrates) {
2124                 WARN_ON(1);
2125                 return;
2126         }
2127
2128         rate = &sband->bitrates[status->rate_idx];
2129
2130         /*
2131          * key references and virtual interfaces are protected using RCU
2132          * and this requires that we are in a read-side RCU section during
2133          * receive processing
2134          */
2135         rcu_read_lock();
2136
2137         /*
2138          * Frames with failed FCS/PLCP checksum are not returned,
2139          * all other frames are returned without radiotap header
2140          * if it was previously present.
2141          * Also, frames with less than 16 bytes are dropped.
2142          */
2143         skb = ieee80211_rx_monitor(local, skb, status, rate);
2144         if (!skb) {
2145                 rcu_read_unlock();
2146                 return;
2147         }
2148
2149         if (!ieee80211_rx_reorder_ampdu(local, skb))
2150                 __ieee80211_rx_handle_packet(hw, skb, status, rate);
2151
2152         rcu_read_unlock();
2153 }
2154 EXPORT_SYMBOL(__ieee80211_rx);
2155
2156 /* This is a version of the rx handler that can be called from hard irq
2157  * context. Post the skb on the queue and schedule the tasklet */
2158 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
2159                           struct ieee80211_rx_status *status)
2160 {
2161         struct ieee80211_local *local = hw_to_local(hw);
2162
2163         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2164
2165         skb->dev = local->mdev;
2166         /* copy status into skb->cb for use by tasklet */
2167         memcpy(skb->cb, status, sizeof(*status));
2168         skb->pkt_type = IEEE80211_RX_MSG;
2169         skb_queue_tail(&local->skb_queue, skb);
2170         tasklet_schedule(&local->tasklet);
2171 }
2172 EXPORT_SYMBOL(ieee80211_rx_irqsafe);