SAFE public projects git trees. - safe/jmp/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/kernel.h>
  13 #include <linux/skbuff.h>
  14 #include <linux/netdevice.h>
  15 #include <linux/etherdevice.h>
  16 #include <linux/rcupdate.h>
  17 #include <net/mac80211.h>
  18 #include <net/ieee80211_radiotap.h>
  19
  20 #include "ieee80211_i.h"
  21 #include "ieee80211_led.h"
  22 #include "wep.h"
  23 #include "wpa.h"
  24 #include "tkip.h"
  25 #include "wme.h"
  26
  27 u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
  28                                 struct tid_ampdu_rx *tid_agg_rx,
  29                                 struct sk_buff *skb, u16 mpdu_seq_num,
  30                                 int bar_req);
  31 /*
  32  * monitor mode reception
  33  *
  34  * This function cleans up the SKB, i.e. it removes all the stuff
  35  * only useful for monitoring.
  36  */
  37 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
  38                                            struct sk_buff *skb,
  39                                            int rtap_len)
  40 {
  41         skb_pull(skb, rtap_len);
  42
  43         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
  44                 if (likely(skb->len > FCS_LEN))
  45                         skb_trim(skb, skb->len - FCS_LEN);
  46                 else {
  47                         /* driver bug */
  48                         WARN_ON(1);
  49                         dev_kfree_skb(skb);
  50                         skb = NULL;
  51                 }
  52         }
  53
  54         return skb;
  55 }
  56
  57 static inline int should_drop_frame(struct ieee80211_rx_status *status,
  58                                     struct sk_buff *skb,
  59                                     int present_fcs_len,
  60                                     int radiotap_len)
  61 {
  62         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
  63
  64         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
  65                 return 1;
  66         if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len))
  67                 return 1;
  68         if (((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_FTYPE)) ==
  69                         cpu_to_le16(IEEE80211_FTYPE_CTL)) &&
  70             ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE)) !=
  71                         cpu_to_le16(IEEE80211_STYPE_PSPOLL)) &&
  72             ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE)) !=
  73                         cpu_to_le16(IEEE80211_STYPE_BACK_REQ)))
  74                 return 1;
  75         return 0;
  76 }
  77
  78 /*
  79  * This function copies a received frame to all monitor interfaces and
  80  * returns a cleaned-up SKB that no longer includes the FCS nor the
  81  * radiotap header the driver might have added.
  82  */
  83 static struct sk_buff *
  84 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
  85                      struct ieee80211_rx_status *status,
  86                      struct ieee80211_rate *rate)
  87 {
  88         struct ieee80211_sub_if_data *sdata;
  89         int needed_headroom = 0;
  90         struct ieee80211_radiotap_header *rthdr;
  91         __le64 *rttsft = NULL;
  92         struct ieee80211_rtap_fixed_data {
  93                 u8 flags;
  94                 u8 rate;
  95                 __le16 chan_freq;
  96                 __le16 chan_flags;
  97                 u8 antsignal;
  98                 u8 padding_for_rxflags;
  99                 __le16 rx_flags;
 100         } __attribute__ ((packed)) *rtfixed;
 101         struct sk_buff *skb, *skb2;
 102         struct net_device *prev_dev = NULL;
 103         int present_fcs_len = 0;
 104         int rtap_len = 0;
 105
 106         /*
 107          * First, we may need to make a copy of the skb because
 108          *  (1) we need to modify it for radiotap (if not present), and
 109          *  (2) the other RX handlers will modify the skb we got.
 110          *
 111          * We don't need to, of course, if we aren't going to return
 112          * the SKB because it has a bad FCS/PLCP checksum.
 113          */
 114         if (status->flag & RX_FLAG_RADIOTAP)
 115                 rtap_len = ieee80211_get_radiotap_len(origskb->data);
 116         else
 117                 /* room for radiotap header, always present fields and TSFT */
 118                 needed_headroom = sizeof(*rthdr) + sizeof(*rtfixed) + 8;
 119
 120         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 121                 present_fcs_len = FCS_LEN;
 122
 123         if (!local->monitors) {
 124                 if (should_drop_frame(status, origskb, present_fcs_len,
 125                                       rtap_len)) {
 126                         dev_kfree_skb(origskb);
 127                         return NULL;
 128                 }
 129
 130                 return remove_monitor_info(local, origskb, rtap_len);
 131         }
 132
 133         if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) {
 134                 /* only need to expand headroom if necessary */
 135                 skb = origskb;
 136                 origskb = NULL;
 137
 138                 /*
 139                  * This shouldn't trigger often because most devices have an
 140                  * RX header they pull before we get here, and that should
 141                  * be big enough for our radiotap information. We should
 142                  * probably export the length to drivers so that we can have
 143                  * them allocate enough headroom to start with.
 144                  */
 145                 if (skb_headroom(skb) < needed_headroom &&
 146                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
 147                         dev_kfree_skb(skb);
 148                         return NULL;
 149                 }
 150         } else {
 151                 /*
 152                  * Need to make a copy and possibly remove radiotap header
 153                  * and FCS from the original.
 154                  */
 155                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
 156
 157                 origskb = remove_monitor_info(local, origskb, rtap_len);
 158
 159                 if (!skb)
 160                         return origskb;
 161         }
 162
 163         /* if necessary, prepend radiotap information */
 164         if (!(status->flag & RX_FLAG_RADIOTAP)) {
 165                 rtfixed = (void *) skb_push(skb, sizeof(*rtfixed));
 166                 rtap_len = sizeof(*rthdr) + sizeof(*rtfixed);
 167                 if (status->flag & RX_FLAG_TSFT) {
 168                         rttsft = (void *) skb_push(skb, sizeof(*rttsft));
 169                         rtap_len += 8;
 170                 }
 171                 rthdr = (void *) skb_push(skb, sizeof(*rthdr));
 172                 memset(rthdr, 0, sizeof(*rthdr));
 173                 memset(rtfixed, 0, sizeof(*rtfixed));
 174                 rthdr->it_present =
 175                         cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 176                                     (1 << IEEE80211_RADIOTAP_RATE) |
 177                                     (1 << IEEE80211_RADIOTAP_CHANNEL) |
 178                                     (1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL) |
 179                                     (1 << IEEE80211_RADIOTAP_RX_FLAGS));
 180                 rtfixed->flags = 0;
 181                 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 182                         rtfixed->flags |= IEEE80211_RADIOTAP_F_FCS;
 183
 184                 if (rttsft) {
 185                         *rttsft = cpu_to_le64(status->mactime);
 186                         rthdr->it_present |=
 187                                 cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
 188                 }
 189
 190                 /* FIXME: when radiotap gets a 'bad PLCP' flag use it here */
 191                 rtfixed->rx_flags = 0;
 192                 if (status->flag &
 193                     (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 194                         rtfixed->rx_flags |=
 195                                 cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS);
 196
 197                 rtfixed->rate = rate->bitrate / 5;
 198
 199                 rtfixed->chan_freq = cpu_to_le16(status->freq);
 200
 201                 if (status->band == IEEE80211_BAND_5GHZ)
 202                         rtfixed->chan_flags =
 203                                 cpu_to_le16(IEEE80211_CHAN_OFDM |
 204                                             IEEE80211_CHAN_5GHZ);
 205                 else
 206                         rtfixed->chan_flags =
 207                                 cpu_to_le16(IEEE80211_CHAN_DYN |
 208                                             IEEE80211_CHAN_2GHZ);
 209
 210                 rtfixed->antsignal = status->ssi;
 211                 rthdr->it_len = cpu_to_le16(rtap_len);
 212         }
 213
 214         skb_reset_mac_header(skb);
 215         skb->ip_summed = CHECKSUM_UNNECESSARY;
 216         skb->pkt_type = PACKET_OTHERHOST;
 217         skb->protocol = htons(ETH_P_802_2);
 218
 219         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 220                 if (!netif_running(sdata->dev))
 221                         continue;
 222
 223                 if (sdata->vif.type != IEEE80211_IF_TYPE_MNTR)
 224                         continue;
 225
 226                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
 227                         continue;
 228
 229                 if (prev_dev) {
 230                         skb2 = skb_clone(skb, GFP_ATOMIC);
 231                         if (skb2) {
 232                                 skb2->dev = prev_dev;
 233                                 netif_rx(skb2);
 234                         }
 235                 }
 236
 237                 prev_dev = sdata->dev;
 238                 sdata->dev->stats.rx_packets++;
 239                 sdata->dev->stats.rx_bytes += skb->len;
 240         }
 241
 242         if (prev_dev) {
 243                 skb->dev = prev_dev;
 244                 netif_rx(skb);
 245         } else
 246                 dev_kfree_skb(skb);
 247
 248         return origskb;
 249 }
 250
 251
 252 static void ieee80211_parse_qos(struct ieee80211_txrx_data *rx)
 253 {
 254         u8 *data = rx->skb->data;
 255         int tid;
 256
 257         /* does the frame have a qos control field? */
 258         if (WLAN_FC_IS_QOS_DATA(rx->fc)) {
 259                 u8 *qc = data + ieee80211_get_hdrlen(rx->fc) - QOS_CONTROL_LEN;
 260                 /* frame has qos control */
 261                 tid = qc[0] & QOS_CONTROL_TID_MASK;
 262                 if (qc[0] & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
 263                         rx->flags |= IEEE80211_TXRXD_RX_AMSDU;
 264                 else
 265                         rx->flags &= ~IEEE80211_TXRXD_RX_AMSDU;
 266         } else {
 267                 if (unlikely((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT)) {
 268                         /* Separate TID for management frames */
 269                         tid = NUM_RX_DATA_QUEUES - 1;
 270                 } else {
 271                         /* no qos control present */
 272                         tid = 0; /* 802.1d - Best Effort */
 273                 }
 274         }
 275
 276         I802_DEBUG_INC(rx->local->wme_rx_queue[tid]);
 277         /* only a debug counter, sta might not be assigned properly yet */
 278         if (rx->sta)
 279                 I802_DEBUG_INC(rx->sta->wme_rx_queue[tid]);
 280
 281         rx->u.rx.queue = tid;
 282         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 283          * For now, set skb->priority to 0 for other cases. */
 284         rx->skb->priority = (tid > 7) ? 0 : tid;
 285 }
 286
 287 static void ieee80211_verify_ip_alignment(struct ieee80211_txrx_data *rx)
 288 {
 289 #ifdef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
 290         int hdrlen;
 291
 292         if (!WLAN_FC_DATA_PRESENT(rx->fc))
 293                 return;
 294
 295         /*
 296          * Drivers are required to align the payload data in a way that
 297          * guarantees that the contained IP header is aligned to a four-
 298          * byte boundary. In the case of regular frames, this simply means
 299          * aligning the payload to a four-byte boundary (because either
 300          * the IP header is directly contained, or IV/RFC1042 headers that
 301          * have a length divisible by four are in front of it.
 302          *
 303          * With A-MSDU frames, however, the payload data address must
 304          * yield two modulo four because there are 14-byte 802.3 headers
 305          * within the A-MSDU frames that push the IP header further back
 306          * to a multiple of four again. Thankfully, the specs were sane
 307          * enough this time around to require padding each A-MSDU subframe
 308          * to a length that is a multiple of four.
 309          *
 310          * Padding like atheros hardware adds which is inbetween the 802.11
 311          * header and the payload is not supported, the driver is required
 312          * to move the 802.11 header further back in that case.
 313          */
 314         hdrlen = ieee80211_get_hdrlen(rx->fc);
 315         if (rx->flags & IEEE80211_TXRXD_RX_AMSDU)
 316                 hdrlen += ETH_HLEN;
 317         WARN_ON_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3);
 318 #endif
 319 }
 320
 321
 322 static u32 ieee80211_rx_load_stats(struct ieee80211_local *local,
 323                                    struct sk_buff *skb,
 324                                    struct ieee80211_rx_status *status,
 325                                    struct ieee80211_rate *rate)
 326 {
 327         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 328         u32 load = 0, hdrtime;
 329
 330         /* Estimate total channel use caused by this frame */
 331
 332         /* 1 bit at 1 Mbit/s takes 1 usec; in channel_use values,
 333          * 1 usec = 1/8 * (1080 / 10) = 13.5 */
 334
 335         if (status->band == IEEE80211_BAND_5GHZ ||
 336             (status->band == IEEE80211_BAND_5GHZ &&
 337              rate->flags & IEEE80211_RATE_ERP_G))
 338                 hdrtime = CHAN_UTIL_HDR_SHORT;
 339         else
 340                 hdrtime = CHAN_UTIL_HDR_LONG;
 341
 342         load = hdrtime;
 343         if (!is_multicast_ether_addr(hdr->addr1))
 344                 load += hdrtime;
 345
 346         /* TODO: optimise again */
 347         load += skb->len * CHAN_UTIL_RATE_LCM / rate->bitrate;
 348
 349         /* Divide channel_use by 8 to avoid wrapping around the counter */
 350         load >>= CHAN_UTIL_SHIFT;
 351
 352         return load;
 353 }
 354
 355 /* rx handlers */
 356
 357 static ieee80211_rx_result
 358 ieee80211_rx_h_if_stats(struct ieee80211_txrx_data *rx)
 359 {
 360         if (rx->sta)
 361                 rx->sta->channel_use_raw += rx->u.rx.load;
 362         rx->sdata->channel_use_raw += rx->u.rx.load;
 363         return RX_CONTINUE;
 364 }
 365
 366 static ieee80211_rx_result
 367 ieee80211_rx_h_passive_scan(struct ieee80211_txrx_data *rx)
 368 {
 369         struct ieee80211_local *local = rx->local;
 370         struct sk_buff *skb = rx->skb;
 371
 372         if (unlikely(local->sta_hw_scanning))
 373                 return ieee80211_sta_rx_scan(rx->dev, skb, rx->u.rx.status);
 374
 375         if (unlikely(local->sta_sw_scanning)) {
 376                 /* drop all the other packets during a software scan anyway */
 377                 if (ieee80211_sta_rx_scan(rx->dev, skb, rx->u.rx.status)
 378                     != RX_QUEUED)
 379                         dev_kfree_skb(skb);
 380                 return RX_QUEUED;
 381         }
 382
 383         if (unlikely(rx->flags & IEEE80211_TXRXD_RXIN_SCAN)) {
 384                 /* scanning finished during invoking of handlers */
 385                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
 386                 return RX_DROP_UNUSABLE;
 387         }
 388
 389         return RX_CONTINUE;
 390 }
 391
 392 static ieee80211_rx_result
 393 ieee80211_rx_h_check(struct ieee80211_txrx_data *rx)
 394 {
 395         struct ieee80211_hdr *hdr;
 396         hdr = (struct ieee80211_hdr *) rx->skb->data;
 397
 398         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 399         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 400                 if (unlikely(rx->fc & IEEE80211_FCTL_RETRY &&
 401                              rx->sta->last_seq_ctrl[rx->u.rx.queue] ==
 402                              hdr->seq_ctrl)) {
 403                         if (rx->flags & IEEE80211_TXRXD_RXRA_MATCH) {
 404                                 rx->local->dot11FrameDuplicateCount++;
 405                                 rx->sta->num_duplicates++;
 406                         }
 407                         return RX_DROP_MONITOR;
 408                 } else
 409                         rx->sta->last_seq_ctrl[rx->u.rx.queue] = hdr->seq_ctrl;
 410         }
 411
 412         if (unlikely(rx->skb->len < 16)) {
 413                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 414                 return RX_DROP_MONITOR;
 415         }
 416
 417         /* Drop disallowed frame classes based on STA auth/assoc state;
 418          * IEEE 802.11, Chap 5.5.
 419          *
 420          * 80211.o does filtering only based on association state, i.e., it
 421          * drops Class 3 frames from not associated stations. hostapd sends
 422          * deauth/disassoc frames when needed. In addition, hostapd is
 423          * responsible for filtering on both auth and assoc states.
 424          */
 425         if (unlikely(((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA ||
 426                       ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_CTL &&
 427                        (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PSPOLL)) &&
 428                      rx->sdata->vif.type != IEEE80211_IF_TYPE_IBSS &&
 429                      (!rx->sta || !(rx->sta->flags & WLAN_STA_ASSOC)))) {
 430                 if ((!(rx->fc & IEEE80211_FCTL_FROMDS) &&
 431                      !(rx->fc & IEEE80211_FCTL_TODS) &&
 432                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA)
 433                     || !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
 434                         /* Drop IBSS frames and frames for other hosts
 435                          * silently. */
 436                         return RX_DROP_MONITOR;
 437                 }
 438
 439                 return RX_DROP_MONITOR;
 440         }
 441
 442         return RX_CONTINUE;
 443 }
 444
 445
 446 static ieee80211_rx_result
 447 ieee80211_rx_h_decrypt(struct ieee80211_txrx_data *rx)
 448 {
 449         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 450         int keyidx;
 451         int hdrlen;
 452         ieee80211_rx_result result = RX_DROP_UNUSABLE;
 453         struct ieee80211_key *stakey = NULL;
 454
 455         /*
 456          * Key selection 101
 457          *
 458          * There are three types of keys:
 459          *  - GTK (group keys)
 460          *  - PTK (pairwise keys)
 461          *  - STK (station-to-station pairwise keys)
 462          *
 463          * When selecting a key, we have to distinguish between multicast
 464          * (including broadcast) and unicast frames, the latter can only
 465          * use PTKs and STKs while the former always use GTKs. Unless, of
 466          * course, actual WEP keys ("pre-RSNA") are used, then unicast
 467          * frames can also use key indizes like GTKs. Hence, if we don't
 468          * have a PTK/STK we check the key index for a WEP key.
 469          *
 470          * Note that in a regular BSS, multicast frames are sent by the
 471          * AP only, associated stations unicast the frame to the AP first
 472          * which then multicasts it on their behalf.
 473          *
 474          * There is also a slight problem in IBSS mode: GTKs are negotiated
 475          * with each station, that is something we don't currently handle.
 476          * The spec seems to expect that one negotiates the same key with
 477          * every station but there's no such requirement; VLANs could be
 478          * possible.
 479          */
 480
 481         if (!(rx->fc & IEEE80211_FCTL_PROTECTED))
 482                 return RX_CONTINUE;
 483
 484         /*
 485          * No point in finding a key and decrypting if the frame is neither
 486          * addressed to us nor a multicast frame.
 487          */
 488         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 489                 return RX_CONTINUE;
 490
 491         if (rx->sta)
 492                 stakey = rcu_dereference(rx->sta->key);
 493
 494         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
 495                 rx->key = stakey;
 496         } else {
 497                 /*
 498                  * The device doesn't give us the IV so we won't be
 499                  * able to look up the key. That's ok though, we
 500                  * don't need to decrypt the frame, we just won't
 501                  * be able to keep statistics accurate.
 502                  * Except for key threshold notifications, should
 503                  * we somehow allow the driver to tell us which key
 504                  * the hardware used if this flag is set?
 505                  */
 506                 if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) &&
 507                     (rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED))
 508                         return RX_CONTINUE;
 509
 510                 hdrlen = ieee80211_get_hdrlen(rx->fc);
 511
 512                 if (rx->skb->len < 8 + hdrlen)
 513                         return RX_DROP_UNUSABLE; /* TODO: count this? */
 514
 515                 /*
 516                  * no need to call ieee80211_wep_get_keyidx,
 517                  * it verifies a bunch of things we've done already
 518                  */
 519                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
 520
 521                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
 522
 523                 /*
 524                  * RSNA-protected unicast frames should always be sent with
 525                  * pairwise or station-to-station keys, but for WEP we allow
 526                  * using a key index as well.
 527                  */
 528                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
 529                     !is_multicast_ether_addr(hdr->addr1))
 530                         rx->key = NULL;
 531         }
 532
 533         if (rx->key) {
 534                 rx->key->tx_rx_count++;
 535                 /* TODO: add threshold stuff again */
 536         } else {
 537 #ifdef CONFIG_MAC80211_DEBUG
 538                 if (net_ratelimit())
 539                         printk(KERN_DEBUG "%s: RX protected frame,"
 540                                " but have no key\n", rx->dev->name);
 541 #endif /* CONFIG_MAC80211_DEBUG */
 542                 return RX_DROP_MONITOR;
 543         }
 544
 545         /* Check for weak IVs if possible */
 546         if (rx->sta && rx->key->conf.alg == ALG_WEP &&
 547             ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) &&
 548             (!(rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED) ||
 549              !(rx->u.rx.status->flag & RX_FLAG_DECRYPTED)) &&
 550             ieee80211_wep_is_weak_iv(rx->skb, rx->key))
 551                 rx->sta->wep_weak_iv_count++;
 552
 553         switch (rx->key->conf.alg) {
 554         case ALG_WEP:
 555                 result = ieee80211_crypto_wep_decrypt(rx);
 556                 break;
 557         case ALG_TKIP:
 558                 result = ieee80211_crypto_tkip_decrypt(rx);
 559                 break;
 560         case ALG_CCMP:
 561                 result = ieee80211_crypto_ccmp_decrypt(rx);
 562                 break;
 563         }
 564
 565         /* either the frame has been decrypted or will be dropped */
 566         rx->u.rx.status->flag |= RX_FLAG_DECRYPTED;
 567
 568         return result;
 569 }
 570
 571 static void ap_sta_ps_start(struct net_device *dev, struct sta_info *sta)
 572 {
 573         struct ieee80211_sub_if_data *sdata;
 574         DECLARE_MAC_BUF(mac);
 575
 576         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 577
 578         if (sdata->bss)
 579                 atomic_inc(&sdata->bss->num_sta_ps);
 580         sta->flags |= WLAN_STA_PS;
 581         sta->pspoll = 0;
 582 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 583         printk(KERN_DEBUG "%s: STA %s aid %d enters power save mode\n",
 584                dev->name, print_mac(mac, sta->addr), sta->aid);
 585 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 586 }
 587
 588 static int ap_sta_ps_end(struct net_device *dev, struct sta_info *sta)
 589 {
 590         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 591         struct sk_buff *skb;
 592         int sent = 0;
 593         struct ieee80211_sub_if_data *sdata;
 594         struct ieee80211_tx_packet_data *pkt_data;
 595         DECLARE_MAC_BUF(mac);
 596
 597         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 598         if (sdata->bss)
 599                 atomic_dec(&sdata->bss->num_sta_ps);
 600         sta->flags &= ~(WLAN_STA_PS | WLAN_STA_TIM);
 601         sta->pspoll = 0;
 602         if (!skb_queue_empty(&sta->ps_tx_buf)) {
 603                 if (local->ops->set_tim)
 604                         local->ops->set_tim(local_to_hw(local), sta->aid, 0);
 605                 if (sdata->bss)
 606                         bss_tim_clear(local, sdata->bss, sta->aid);
 607         }
 608 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 609         printk(KERN_DEBUG "%s: STA %s aid %d exits power save mode\n",
 610                dev->name, print_mac(mac, sta->addr), sta->aid);
 611 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 612         /* Send all buffered frames to the station */
 613         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
 614                 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 615                 sent++;
 616                 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
 617                 dev_queue_xmit(skb);
 618         }
 619         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
 620                 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 621                 local->total_ps_buffered--;
 622                 sent++;
 623 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 624                 printk(KERN_DEBUG "%s: STA %s aid %d send PS frame "
 625                        "since STA not sleeping anymore\n", dev->name,
 626                        print_mac(mac, sta->addr), sta->aid);
 627 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 628                 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
 629                 dev_queue_xmit(skb);
 630         }
 631
 632         return sent;
 633 }
 634
 635 static ieee80211_rx_result
 636 ieee80211_rx_h_sta_process(struct ieee80211_txrx_data *rx)
 637 {
 638         struct sta_info *sta = rx->sta;
 639         struct net_device *dev = rx->dev;
 640         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 641
 642         if (!sta)
 643                 return RX_CONTINUE;
 644
 645         /* Update last_rx only for IBSS packets which are for the current
 646          * BSSID to avoid keeping the current IBSS network alive in cases where
 647          * other STAs are using different BSSID. */
 648         if (rx->sdata->vif.type == IEEE80211_IF_TYPE_IBSS) {
 649                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
 650                                                 IEEE80211_IF_TYPE_IBSS);
 651                 if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0)
 652                         sta->last_rx = jiffies;
 653         } else
 654         if (!is_multicast_ether_addr(hdr->addr1) ||
 655             rx->sdata->vif.type == IEEE80211_IF_TYPE_STA) {
 656                 /* Update last_rx only for unicast frames in order to prevent
 657                  * the Probe Request frames (the only broadcast frames from a
 658                  * STA in infrastructure mode) from keeping a connection alive.
 659                  */
 660                 sta->last_rx = jiffies;
 661         }
 662
 663         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 664                 return RX_CONTINUE;
 665
 666         sta->rx_fragments++;
 667         sta->rx_bytes += rx->skb->len;
 668         sta->last_rssi = rx->u.rx.status->ssi;
 669         sta->last_signal = rx->u.rx.status->signal;
 670         sta->last_noise = rx->u.rx.status->noise;
 671
 672         if (!(rx->fc & IEEE80211_FCTL_MOREFRAGS)) {
 673                 /* Change STA power saving mode only in the end of a frame
 674                  * exchange sequence */
 675                 if ((sta->flags & WLAN_STA_PS) && !(rx->fc & IEEE80211_FCTL_PM))
 676                         rx->u.rx.sent_ps_buffered += ap_sta_ps_end(dev, sta);
 677                 else if (!(sta->flags & WLAN_STA_PS) &&
 678                          (rx->fc & IEEE80211_FCTL_PM))
 679                         ap_sta_ps_start(dev, sta);
 680         }
 681
 682         /* Drop data::nullfunc frames silently, since they are used only to
 683          * control station power saving mode. */
 684         if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 685             (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_NULLFUNC) {
 686                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
 687                 /* Update counter and free packet here to avoid counting this
 688                  * as a dropped packed. */
 689                 sta->rx_packets++;
 690                 dev_kfree_skb(rx->skb);
 691                 return RX_QUEUED;
 692         }
 693
 694         return RX_CONTINUE;
 695 } /* ieee80211_rx_h_sta_process */
 696
 697 static inline struct ieee80211_fragment_entry *
 698 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
 699                          unsigned int frag, unsigned int seq, int rx_queue,
 700                          struct sk_buff **skb)
 701 {
 702         struct ieee80211_fragment_entry *entry;
 703         int idx;
 704
 705         idx = sdata->fragment_next;
 706         entry = &sdata->fragments[sdata->fragment_next++];
 707         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
 708                 sdata->fragment_next = 0;
 709
 710         if (!skb_queue_empty(&entry->skb_list)) {
 711 #ifdef CONFIG_MAC80211_DEBUG
 712                 struct ieee80211_hdr *hdr =
 713                         (struct ieee80211_hdr *) entry->skb_list.next->data;
 714                 DECLARE_MAC_BUF(mac);
 715                 DECLARE_MAC_BUF(mac2);
 716                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
 717                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
 718                        "addr1=%s addr2=%s\n",
 719                        sdata->dev->name, idx,
 720                        jiffies - entry->first_frag_time, entry->seq,
 721                        entry->last_frag, print_mac(mac, hdr->addr1),
 722                        print_mac(mac2, hdr->addr2));
 723 #endif /* CONFIG_MAC80211_DEBUG */
 724                 __skb_queue_purge(&entry->skb_list);
 725         }
 726
 727         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
 728         *skb = NULL;
 729         entry->first_frag_time = jiffies;
 730         entry->seq = seq;
 731         entry->rx_queue = rx_queue;
 732         entry->last_frag = frag;
 733         entry->ccmp = 0;
 734         entry->extra_len = 0;
 735
 736         return entry;
 737 }
 738
 739 static inline struct ieee80211_fragment_entry *
 740 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
 741                           u16 fc, unsigned int frag, unsigned int seq,
 742                           int rx_queue, struct ieee80211_hdr *hdr)
 743 {
 744         struct ieee80211_fragment_entry *entry;
 745         int i, idx;
 746
 747         idx = sdata->fragment_next;
 748         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
 749                 struct ieee80211_hdr *f_hdr;
 750                 u16 f_fc;
 751
 752                 idx--;
 753                 if (idx < 0)
 754                         idx = IEEE80211_FRAGMENT_MAX - 1;
 755
 756                 entry = &sdata->fragments[idx];
 757                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
 758                     entry->rx_queue != rx_queue ||
 759                     entry->last_frag + 1 != frag)
 760                         continue;
 761
 762                 f_hdr = (struct ieee80211_hdr *) entry->skb_list.next->data;
 763                 f_fc = le16_to_cpu(f_hdr->frame_control);
 764
 765                 if ((fc & IEEE80211_FCTL_FTYPE) != (f_fc & IEEE80211_FCTL_FTYPE) ||
 766                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
 767                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
 768                         continue;
 769
 770                 if (entry->first_frag_time + 2 * HZ < jiffies) {
 771                         __skb_queue_purge(&entry->skb_list);
 772                         continue;
 773                 }
 774                 return entry;
 775         }
 776
 777         return NULL;
 778 }
 779
 780 static ieee80211_rx_result
 781 ieee80211_rx_h_defragment(struct ieee80211_txrx_data *rx)
 782 {
 783         struct ieee80211_hdr *hdr;
 784         u16 sc;
 785         unsigned int frag, seq;
 786         struct ieee80211_fragment_entry *entry;
 787         struct sk_buff *skb;
 788         DECLARE_MAC_BUF(mac);
 789
 790         hdr = (struct ieee80211_hdr *) rx->skb->data;
 791         sc = le16_to_cpu(hdr->seq_ctrl);
 792         frag = sc & IEEE80211_SCTL_FRAG;
 793
 794         if (likely((!(rx->fc & IEEE80211_FCTL_MOREFRAGS) && frag == 0) ||
 795                    (rx->skb)->len < 24 ||
 796                    is_multicast_ether_addr(hdr->addr1))) {
 797                 /* not fragmented */
 798                 goto out;
 799         }
 800         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
 801
 802         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
 803
 804         if (frag == 0) {
 805                 /* This is the first fragment of a new frame. */
 806                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
 807                                                  rx->u.rx.queue, &(rx->skb));
 808                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
 809                     (rx->fc & IEEE80211_FCTL_PROTECTED)) {
 810                         /* Store CCMP PN so that we can verify that the next
 811                          * fragment has a sequential PN value. */
 812                         entry->ccmp = 1;
 813                         memcpy(entry->last_pn,
 814                                rx->key->u.ccmp.rx_pn[rx->u.rx.queue],
 815                                CCMP_PN_LEN);
 816                 }
 817                 return RX_QUEUED;
 818         }
 819
 820         /* This is a fragment for a frame that should already be pending in
 821          * fragment cache. Add this fragment to the end of the pending entry.
 822          */
 823         entry = ieee80211_reassemble_find(rx->sdata, rx->fc, frag, seq,
 824                                           rx->u.rx.queue, hdr);
 825         if (!entry) {
 826                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 827                 return RX_DROP_MONITOR;
 828         }
 829
 830         /* Verify that MPDUs within one MSDU have sequential PN values.
 831          * (IEEE 802.11i, 8.3.3.4.5) */
 832         if (entry->ccmp) {
 833                 int i;
 834                 u8 pn[CCMP_PN_LEN], *rpn;
 835                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
 836                         return RX_DROP_UNUSABLE;
 837                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
 838                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
 839                         pn[i]++;
 840                         if (pn[i])
 841                                 break;
 842                 }
 843                 rpn = rx->key->u.ccmp.rx_pn[rx->u.rx.queue];
 844                 if (memcmp(pn, rpn, CCMP_PN_LEN) != 0) {
 845                         if (net_ratelimit())
 846                                 printk(KERN_DEBUG "%s: defrag: CCMP PN not "
 847                                        "sequential A2=%s"
 848                                        " PN=%02x%02x%02x%02x%02x%02x "
 849                                        "(expected %02x%02x%02x%02x%02x%02x)\n",
 850                                        rx->dev->name, print_mac(mac, hdr->addr2),
 851                                        rpn[0], rpn[1], rpn[2], rpn[3], rpn[4],
 852                                        rpn[5], pn[0], pn[1], pn[2], pn[3],
 853                                        pn[4], pn[5]);
 854                         return RX_DROP_UNUSABLE;
 855                 }
 856                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
 857         }
 858
 859         skb_pull(rx->skb, ieee80211_get_hdrlen(rx->fc));
 860         __skb_queue_tail(&entry->skb_list, rx->skb);
 861         entry->last_frag = frag;
 862         entry->extra_len += rx->skb->len;
 863         if (rx->fc & IEEE80211_FCTL_MOREFRAGS) {
 864                 rx->skb = NULL;
 865                 return RX_QUEUED;
 866         }
 867
 868         rx->skb = __skb_dequeue(&entry->skb_list);
 869         if (skb_tailroom(rx->skb) < entry->extra_len) {
 870                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
 871                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
 872                                               GFP_ATOMIC))) {
 873                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 874                         __skb_queue_purge(&entry->skb_list);
 875                         return RX_DROP_UNUSABLE;
 876                 }
 877         }
 878         while ((skb = __skb_dequeue(&entry->skb_list))) {
 879                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
 880                 dev_kfree_skb(skb);
 881         }
 882
 883         /* Complete frame has been reassembled - process it now */
 884         rx->flags |= IEEE80211_TXRXD_FRAGMENTED;
 885
 886  out:
 887         if (rx->sta)
 888                 rx->sta->rx_packets++;
 889         if (is_multicast_ether_addr(hdr->addr1))
 890                 rx->local->dot11MulticastReceivedFrameCount++;
 891         else
 892                 ieee80211_led_rx(rx->local);
 893         return RX_CONTINUE;
 894 }
 895
 896 static ieee80211_rx_result
 897 ieee80211_rx_h_ps_poll(struct ieee80211_txrx_data *rx)
 898 {
 899         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
 900         struct sk_buff *skb;
 901         int no_pending_pkts;
 902         DECLARE_MAC_BUF(mac);
 903
 904         if (likely(!rx->sta ||
 905                    (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL ||
 906                    (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PSPOLL ||
 907                    !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)))
 908                 return RX_CONTINUE;
 909
 910         if ((sdata->vif.type != IEEE80211_IF_TYPE_AP) &&
 911             (sdata->vif.type != IEEE80211_IF_TYPE_VLAN))
 912                 return RX_DROP_UNUSABLE;
 913
 914         skb = skb_dequeue(&rx->sta->tx_filtered);
 915         if (!skb) {
 916                 skb = skb_dequeue(&rx->sta->ps_tx_buf);
 917                 if (skb)
 918                         rx->local->total_ps_buffered--;
 919         }
 920         no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
 921                 skb_queue_empty(&rx->sta->ps_tx_buf);
 922
 923         if (skb) {
 924                 struct ieee80211_hdr *hdr =
 925                         (struct ieee80211_hdr *) skb->data;
 926
 927                 /* tell TX path to send one frame even though the STA may
 928                  * still remain is PS mode after this frame exchange */
 929                 rx->sta->pspoll = 1;
 930
 931 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 932                 printk(KERN_DEBUG "STA %s aid %d: PS Poll (entries after %d)\n",
 933                        print_mac(mac, rx->sta->addr), rx->sta->aid,
 934                        skb_queue_len(&rx->sta->ps_tx_buf));
 935 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 936
 937                 /* Use MoreData flag to indicate whether there are more
 938                  * buffered frames for this STA */
 939                 if (no_pending_pkts) {
 940                         hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
 941                         rx->sta->flags &= ~WLAN_STA_TIM;
 942                 } else
 943                         hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
 944
 945                 dev_queue_xmit(skb);
 946
 947                 if (no_pending_pkts) {
 948                         if (rx->local->ops->set_tim)
 949                                 rx->local->ops->set_tim(local_to_hw(rx->local),
 950                                                        rx->sta->aid, 0);
 951                         if (rx->sdata->bss)
 952                                 bss_tim_clear(rx->local, rx->sdata->bss, rx->sta->aid);
 953                 }
 954 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 955         } else if (!rx->u.rx.sent_ps_buffered) {
 956                 printk(KERN_DEBUG "%s: STA %s sent PS Poll even "
 957                        "though there is no buffered frames for it\n",
 958                        rx->dev->name, print_mac(mac, rx->sta->addr));
 959 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 960
 961         }
 962
 963         /* Free PS Poll skb here instead of returning RX_DROP that would
 964          * count as an dropped frame. */
 965         dev_kfree_skb(rx->skb);
 966
 967         return RX_QUEUED;
 968 }
 969
 970 static ieee80211_rx_result
 971 ieee80211_rx_h_remove_qos_control(struct ieee80211_txrx_data *rx)
 972 {
 973         u16 fc = rx->fc;
 974         u8 *data = rx->skb->data;
 975         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) data;
 976
 977         if (!WLAN_FC_IS_QOS_DATA(fc))
 978                 return RX_CONTINUE;
 979
 980         /* remove the qos control field, update frame type and meta-data */
 981         memmove(data + 2, data, ieee80211_get_hdrlen(fc) - 2);
 982         hdr = (struct ieee80211_hdr *) skb_pull(rx->skb, 2);
 983         /* change frame type to non QOS */
 984         rx->fc = fc &= ~IEEE80211_STYPE_QOS_DATA;
 985         hdr->frame_control = cpu_to_le16(fc);
 986
 987         return RX_CONTINUE;
 988 }
 989
 990 static int
 991 ieee80211_802_1x_port_control(struct ieee80211_txrx_data *rx)
 992 {
 993         if (unlikely(!rx->sta || !(rx->sta->flags & WLAN_STA_AUTHORIZED))) {
 994 #ifdef CONFIG_MAC80211_DEBUG
 995                 if (net_ratelimit())
 996                         printk(KERN_DEBUG "%s: dropped frame "
 997                                "(unauthorized port)\n", rx->dev->name);
 998 #endif /* CONFIG_MAC80211_DEBUG */
 999                 return -EACCES;
1000         }
1001
1002         return 0;
1003 }
1004
1005 static int
1006 ieee80211_drop_unencrypted(struct ieee80211_txrx_data *rx)
1007 {
1008         /*
1009          * Pass through unencrypted frames if the hardware has
1010          * decrypted them already.
1011          */
1012         if (rx->u.rx.status->flag & RX_FLAG_DECRYPTED)
1013                 return 0;
1014
1015         /* Drop unencrypted frames if key is set. */
1016         if (unlikely(!(rx->fc & IEEE80211_FCTL_PROTECTED) &&
1017                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
1018                      (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
1019                      (rx->key || rx->sdata->drop_unencrypted))) {
1020                 if (net_ratelimit())
1021                         printk(KERN_DEBUG "%s: RX non-WEP frame, but expected "
1022                                "encryption\n", rx->dev->name);
1023                 return -EACCES;
1024         }
1025         return 0;
1026 }
1027
1028 static int
1029 ieee80211_data_to_8023(struct ieee80211_txrx_data *rx)
1030 {
1031         struct net_device *dev = rx->dev;
1032         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
1033         u16 fc, hdrlen, ethertype;
1034         u8 *payload;
1035         u8 dst[ETH_ALEN];
1036         u8 src[ETH_ALEN];
1037         struct sk_buff *skb = rx->skb;
1038         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1039         DECLARE_MAC_BUF(mac);
1040         DECLARE_MAC_BUF(mac2);
1041         DECLARE_MAC_BUF(mac3);
1042         DECLARE_MAC_BUF(mac4);
1043
1044         fc = rx->fc;
1045
1046         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1047                 return -1;
1048
1049         hdrlen = ieee80211_get_hdrlen(fc);
1050
1051         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
1052          * header
1053          * IEEE 802.11 address fields:
1054          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
1055          *   0     0   DA    SA    BSSID n/a
1056          *   0     1   DA    BSSID SA    n/a
1057          *   1     0   BSSID SA    DA    n/a
1058          *   1     1   RA    TA    DA    SA
1059          */
1060
1061         switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
1062         case IEEE80211_FCTL_TODS:
1063                 /* BSSID SA DA */
1064                 memcpy(dst, hdr->addr3, ETH_ALEN);
1065                 memcpy(src, hdr->addr2, ETH_ALEN);
1066
1067                 if (unlikely(sdata->vif.type != IEEE80211_IF_TYPE_AP &&
1068                              sdata->vif.type != IEEE80211_IF_TYPE_VLAN)) {
1069                         if (net_ratelimit())
1070                                 printk(KERN_DEBUG "%s: dropped ToDS frame "
1071                                        "(BSSID=%s SA=%s DA=%s)\n",
1072                                        dev->name,
1073                                        print_mac(mac, hdr->addr1),
1074                                        print_mac(mac2, hdr->addr2),
1075                                        print_mac(mac3, hdr->addr3));
1076                         return -1;
1077                 }
1078                 break;
1079         case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
1080                 /* RA TA DA SA */
1081                 memcpy(dst, hdr->addr3, ETH_ALEN);
1082                 memcpy(src, hdr->addr4, ETH_ALEN);
1083
1084                 if (unlikely(sdata->vif.type != IEEE80211_IF_TYPE_WDS)) {
1085                         if (net_ratelimit())
1086                                 printk(KERN_DEBUG "%s: dropped FromDS&ToDS "
1087                                        "frame (RA=%s TA=%s DA=%s SA=%s)\n",
1088                                        rx->dev->name,
1089                                        print_mac(mac, hdr->addr1),
1090                                        print_mac(mac2, hdr->addr2),
1091                                        print_mac(mac3, hdr->addr3),
1092                                        print_mac(mac4, hdr->addr4));
1093                         return -1;
1094                 }
1095                 break;
1096         case IEEE80211_FCTL_FROMDS:
1097                 /* DA BSSID SA */
1098                 memcpy(dst, hdr->addr1, ETH_ALEN);
1099                 memcpy(src, hdr->addr3, ETH_ALEN);
1100
1101                 if (sdata->vif.type != IEEE80211_IF_TYPE_STA ||
1102                     (is_multicast_ether_addr(dst) &&
1103                      !compare_ether_addr(src, dev->dev_addr)))
1104                         return -1;
1105                 break;
1106         case 0:
1107                 /* DA SA BSSID */
1108                 memcpy(dst, hdr->addr1, ETH_ALEN);
1109                 memcpy(src, hdr->addr2, ETH_ALEN);
1110
1111                 if (sdata->vif.type != IEEE80211_IF_TYPE_IBSS) {
1112                         if (net_ratelimit()) {
1113                                 printk(KERN_DEBUG "%s: dropped IBSS frame "
1114                                        "(DA=%s SA=%s BSSID=%s)\n",
1115                                        dev->name,
1116                                        print_mac(mac, hdr->addr1),
1117                                        print_mac(mac2, hdr->addr2),
1118                                        print_mac(mac3, hdr->addr3));
1119                         }
1120                         return -1;
1121                 }
1122                 break;
1123         }
1124
1125         if (unlikely(skb->len - hdrlen < 8)) {
1126                 if (net_ratelimit()) {
1127                         printk(KERN_DEBUG "%s: RX too short data frame "
1128                                "payload\n", dev->name);
1129                 }
1130                 return -1;
1131         }
1132
1133         payload = skb->data + hdrlen;
1134         ethertype = (payload[6] << 8) | payload[7];
1135
1136         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1137                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1138                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1139                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1140                  * replace EtherType */
1141                 skb_pull(skb, hdrlen + 6);
1142                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1143                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1144         } else {
1145                 struct ethhdr *ehdr;
1146                 __be16 len;
1147
1148                 skb_pull(skb, hdrlen);
1149                 len = htons(skb->len);
1150                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1151                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1152                 memcpy(ehdr->h_source, src, ETH_ALEN);
1153                 ehdr->h_proto = len;
1154         }
1155         return 0;
1156 }
1157
1158 /*
1159  * requires that rx->skb is a frame with ethernet header
1160  */
1161 static bool ieee80211_frame_allowed(struct ieee80211_txrx_data *rx)
1162 {
1163         static const u8 pae_group_addr[ETH_ALEN]
1164                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1165         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1166
1167         /*
1168          * Allow EAPOL frames to us/the PAE group address regardless
1169          * of whether the frame was encrypted or not.
1170          */
1171         if (ehdr->h_proto == htons(ETH_P_PAE) &&
1172             (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
1173              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1174                 return true;
1175
1176         if (ieee80211_802_1x_port_control(rx) ||
1177             ieee80211_drop_unencrypted(rx))
1178                 return false;
1179
1180         return true;
1181 }
1182
1183 /*
1184  * requires that rx->skb is a frame with ethernet header
1185  */
1186 static void
1187 ieee80211_deliver_skb(struct ieee80211_txrx_data *rx)
1188 {
1189         struct net_device *dev = rx->dev;
1190         struct ieee80211_local *local = rx->local;
1191         struct sk_buff *skb, *xmit_skb;
1192         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1193         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1194         struct sta_info *dsta;
1195
1196         skb = rx->skb;
1197         xmit_skb = NULL;
1198
1199         if (local->bridge_packets && (sdata->vif.type == IEEE80211_IF_TYPE_AP ||
1200                                       sdata->vif.type == IEEE80211_IF_TYPE_VLAN) &&
1201             (rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
1202                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1203                         /*
1204                          * send multicast frames both to higher layers in
1205                          * local net stack and back to the wireless medium
1206                          */
1207                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1208                         if (!xmit_skb && net_ratelimit())
1209                                 printk(KERN_DEBUG "%s: failed to clone "
1210                                        "multicast frame\n", dev->name);
1211                 } else {
1212                         dsta = sta_info_get(local, skb->data);
1213                         if (dsta && dsta->dev == dev) {
1214                                 /*
1215                                  * The destination station is associated to
1216                                  * this AP (in this VLAN), so send the frame
1217                                  * directly to it and do not pass it to local
1218                                  * net stack.
1219                                  */
1220                                 xmit_skb = skb;
1221                                 skb = NULL;
1222                         }
1223                         if (dsta)
1224                                 sta_info_put(dsta);
1225                 }
1226         }
1227
1228         if (skb) {
1229                 /* deliver to local stack */
1230                 skb->protocol = eth_type_trans(skb, dev);
1231                 memset(skb->cb, 0, sizeof(skb->cb));
1232                 netif_rx(skb);
1233         }
1234
1235         if (xmit_skb) {
1236                 /* send to wireless media */
1237                 xmit_skb->protocol = htons(ETH_P_802_3);
1238                 skb_reset_network_header(xmit_skb);
1239                 skb_reset_mac_header(xmit_skb);
1240                 dev_queue_xmit(xmit_skb);
1241         }
1242 }
1243
1244 static ieee80211_rx_result
1245 ieee80211_rx_h_amsdu(struct ieee80211_txrx_data *rx)
1246 {
1247         struct net_device *dev = rx->dev;
1248         struct ieee80211_local *local = rx->local;
1249         u16 fc, ethertype;
1250         u8 *payload;
1251         struct sk_buff *skb = rx->skb, *frame = NULL;
1252         const struct ethhdr *eth;
1253         int remaining, err;
1254         u8 dst[ETH_ALEN];
1255         u8 src[ETH_ALEN];
1256         DECLARE_MAC_BUF(mac);
1257
1258         fc = rx->fc;
1259         if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
1260                 return RX_CONTINUE;
1261
1262         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1263                 return RX_DROP_MONITOR;
1264
1265         if (!(rx->flags & IEEE80211_TXRXD_RX_AMSDU))
1266                 return RX_CONTINUE;
1267
1268         err = ieee80211_data_to_8023(rx);
1269         if (unlikely(err))
1270                 return RX_DROP_UNUSABLE;
1271
1272         skb->dev = dev;
1273
1274         dev->stats.rx_packets++;
1275         dev->stats.rx_bytes += skb->len;
1276
1277         /* skip the wrapping header */
1278         eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
1279         if (!eth)
1280                 return RX_DROP_UNUSABLE;
1281
1282         while (skb != frame) {
1283                 u8 padding;
1284                 __be16 len = eth->h_proto;
1285                 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
1286
1287                 remaining = skb->len;
1288                 memcpy(dst, eth->h_dest, ETH_ALEN);
1289                 memcpy(src, eth->h_source, ETH_ALEN);
1290
1291                 padding = ((4 - subframe_len) & 0x3);
1292                 /* the last MSDU has no padding */
1293                 if (subframe_len > remaining) {
1294                         printk(KERN_DEBUG "%s: wrong buffer size", dev->name);
1295                         return RX_DROP_UNUSABLE;
1296                 }
1297
1298                 skb_pull(skb, sizeof(struct ethhdr));
1299                 /* if last subframe reuse skb */
1300                 if (remaining <= subframe_len + padding)
1301                         frame = skb;
1302                 else {
1303                         frame = dev_alloc_skb(local->hw.extra_tx_headroom +
1304                                               subframe_len);
1305
1306                         if (frame == NULL)
1307                                 return RX_DROP_UNUSABLE;
1308
1309                         skb_reserve(frame, local->hw.extra_tx_headroom +
1310                                     sizeof(struct ethhdr));
1311                         memcpy(skb_put(frame, ntohs(len)), skb->data,
1312                                 ntohs(len));
1313
1314                         eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
1315                                                         padding);
1316                         if (!eth) {
1317                                 printk(KERN_DEBUG "%s: wrong buffer size ",
1318                                        dev->name);
1319                                 dev_kfree_skb(frame);
1320                                 return RX_DROP_UNUSABLE;
1321                         }
1322                 }
1323
1324                 skb_reset_network_header(frame);
1325                 frame->dev = dev;
1326                 frame->priority = skb->priority;
1327                 rx->skb = frame;
1328
1329                 payload = frame->data;
1330                 ethertype = (payload[6] << 8) | payload[7];
1331
1332                 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1333                             ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1334                            compare_ether_addr(payload,
1335                                               bridge_tunnel_header) == 0)) {
1336                         /* remove RFC1042 or Bridge-Tunnel
1337                          * encapsulation and replace EtherType */
1338                         skb_pull(frame, 6);
1339                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1340                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1341                 } else {
1342                         memcpy(skb_push(frame, sizeof(__be16)),
1343                                &len, sizeof(__be16));
1344                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1345                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1346                 }
1347
1348                 if (!ieee80211_frame_allowed(rx)) {
1349                         if (skb == frame) /* last frame */
1350                                 return RX_DROP_UNUSABLE;
1351                         dev_kfree_skb(frame);
1352                         continue;
1353                 }
1354
1355                 ieee80211_deliver_skb(rx);
1356         }
1357
1358         return RX_QUEUED;
1359 }
1360
1361 static ieee80211_rx_result
1362 ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
1363 {
1364         struct net_device *dev = rx->dev;
1365         u16 fc;
1366         int err;
1367
1368         fc = rx->fc;
1369         if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
1370                 return RX_CONTINUE;
1371
1372         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1373                 return RX_DROP_MONITOR;
1374
1375         err = ieee80211_data_to_8023(rx);
1376         if (unlikely(err))
1377                 return RX_DROP_UNUSABLE;
1378
1379         if (!ieee80211_frame_allowed(rx))
1380                 return RX_DROP_MONITOR;
1381
1382         rx->skb->dev = dev;
1383
1384         dev->stats.rx_packets++;
1385         dev->stats.rx_bytes += rx->skb->len;
1386
1387         ieee80211_deliver_skb(rx);
1388
1389         return RX_QUEUED;
1390 }
1391
1392 static ieee80211_rx_result
1393 ieee80211_rx_h_ctrl(struct ieee80211_txrx_data *rx)
1394 {
1395         struct ieee80211_local *local = rx->local;
1396         struct ieee80211_hw *hw = &local->hw;
1397         struct sk_buff *skb = rx->skb;
1398         struct ieee80211_bar *bar = (struct ieee80211_bar *) skb->data;
1399         struct tid_ampdu_rx *tid_agg_rx;
1400         u16 start_seq_num;
1401         u16 tid;
1402
1403         if (likely((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL))
1404                 return RX_CONTINUE;
1405
1406         if ((rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_BACK_REQ) {
1407                 if (!rx->sta)
1408                         return RX_CONTINUE;
1409                 tid = le16_to_cpu(bar->control) >> 12;
1410                 tid_agg_rx = &(rx->sta->ampdu_mlme.tid_rx[tid]);
1411                 if (tid_agg_rx->state != HT_AGG_STATE_OPERATIONAL)
1412                         return RX_CONTINUE;
1413
1414                 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1415
1416                 /* reset session timer */
1417                 if (tid_agg_rx->timeout) {
1418                         unsigned long expires =
1419                                 jiffies + (tid_agg_rx->timeout / 1000) * HZ;
1420                         mod_timer(&tid_agg_rx->session_timer, expires);
1421                 }
1422
1423                 /* manage reordering buffer according to requested */
1424                 /* sequence number */
1425                 rcu_read_lock();
1426                 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL,
1427                                                  start_seq_num, 1);
1428                 rcu_read_unlock();
1429                 return RX_DROP_UNUSABLE;
1430         }
1431
1432         return RX_CONTINUE;
1433 }
1434
1435 static ieee80211_rx_result
1436 ieee80211_rx_h_mgmt(struct ieee80211_txrx_data *rx)
1437 {
1438         struct ieee80211_sub_if_data *sdata;
1439
1440         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
1441                 return RX_DROP_MONITOR;
1442
1443         sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1444         if ((sdata->vif.type == IEEE80211_IF_TYPE_STA ||
1445              sdata->vif.type == IEEE80211_IF_TYPE_IBSS) &&
1446             !(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME))
1447                 ieee80211_sta_rx_mgmt(rx->dev, rx->skb, rx->u.rx.status);
1448         else
1449                 return RX_DROP_MONITOR;
1450
1451         return RX_QUEUED;
1452 }
1453
1454 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1455                                             struct ieee80211_hdr *hdr,
1456                                             struct ieee80211_txrx_data *rx)
1457 {
1458         int keyidx, hdrlen;
1459         DECLARE_MAC_BUF(mac);
1460         DECLARE_MAC_BUF(mac2);
1461
1462         hdrlen = ieee80211_get_hdrlen_from_skb(rx->skb);
1463         if (rx->skb->len >= hdrlen + 4)
1464                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1465         else
1466                 keyidx = -1;
1467
1468         if (net_ratelimit())
1469                 printk(KERN_DEBUG "%s: TKIP hwaccel reported Michael MIC "
1470                        "failure from %s to %s keyidx=%d\n",
1471                        dev->name, print_mac(mac, hdr->addr2),
1472                        print_mac(mac2, hdr->addr1), keyidx);
1473
1474         if (!rx->sta) {
1475                 /*
1476                  * Some hardware seem to generate incorrect Michael MIC
1477                  * reports; ignore them to avoid triggering countermeasures.
1478                  */
1479                 if (net_ratelimit())
1480                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1481                                "error for unknown address %s\n",
1482                                dev->name, print_mac(mac, hdr->addr2));
1483                 goto ignore;
1484         }
1485
1486         if (!(rx->fc & IEEE80211_FCTL_PROTECTED)) {
1487                 if (net_ratelimit())
1488                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1489                                "error for a frame with no PROTECTED flag (src "
1490                                "%s)\n", dev->name, print_mac(mac, hdr->addr2));
1491                 goto ignore;
1492         }
1493
1494         if (rx->sdata->vif.type == IEEE80211_IF_TYPE_AP && keyidx) {
1495                 /*
1496                  * APs with pairwise keys should never receive Michael MIC
1497                  * errors for non-zero keyidx because these are reserved for
1498                  * group keys and only the AP is sending real multicast
1499                  * frames in the BSS.
1500                  */
1501                 if (net_ratelimit())
1502                         printk(KERN_DEBUG "%s: ignored Michael MIC error for "
1503                                "a frame with non-zero keyidx (%d)"
1504                                " (src %s)\n", dev->name, keyidx,
1505                                print_mac(mac, hdr->addr2));
1506                 goto ignore;
1507         }
1508
1509         if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
1510             ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
1511              (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)) {
1512                 if (net_ratelimit())
1513                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1514                                "error for a frame that cannot be encrypted "
1515                                "(fc=0x%04x) (src %s)\n",
1516                                dev->name, rx->fc, print_mac(mac, hdr->addr2));
1517                 goto ignore;
1518         }
1519
1520         mac80211_ev_michael_mic_failure(rx->dev, keyidx, hdr);
1521  ignore:
1522         dev_kfree_skb(rx->skb);
1523         rx->skb = NULL;
1524 }
1525
1526 static void ieee80211_rx_cooked_monitor(struct ieee80211_txrx_data *rx)
1527 {
1528         struct ieee80211_sub_if_data *sdata;
1529         struct ieee80211_local *local = rx->local;
1530         struct ieee80211_rtap_hdr {
1531                 struct ieee80211_radiotap_header hdr;
1532                 u8 flags;
1533                 u8 rate;
1534                 __le16 chan_freq;
1535                 __le16 chan_flags;
1536         } __attribute__ ((packed)) *rthdr;
1537         struct sk_buff *skb = rx->skb, *skb2;
1538         struct net_device *prev_dev = NULL;
1539         struct ieee80211_rx_status *status = rx->u.rx.status;
1540
1541         if (rx->flags & IEEE80211_TXRXD_RX_CMNTR_REPORTED)
1542                 goto out_free_skb;
1543
1544         if (skb_headroom(skb) < sizeof(*rthdr) &&
1545             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
1546                 goto out_free_skb;
1547
1548         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
1549         memset(rthdr, 0, sizeof(*rthdr));
1550         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
1551         rthdr->hdr.it_present =
1552                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
1553                             (1 << IEEE80211_RADIOTAP_RATE) |
1554                             (1 << IEEE80211_RADIOTAP_CHANNEL));
1555
1556         rthdr->rate = rx->u.rx.rate->bitrate / 5;
1557         rthdr->chan_freq = cpu_to_le16(status->freq);
1558
1559         if (status->band == IEEE80211_BAND_5GHZ)
1560                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
1561                                                 IEEE80211_CHAN_5GHZ);
1562         else
1563                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
1564                                                 IEEE80211_CHAN_2GHZ);
1565
1566         skb_set_mac_header(skb, 0);
1567         skb->ip_summed = CHECKSUM_UNNECESSARY;
1568         skb->pkt_type = PACKET_OTHERHOST;
1569         skb->protocol = htons(ETH_P_802_2);
1570
1571         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1572                 if (!netif_running(sdata->dev))
1573                         continue;
1574
1575                 if (sdata->vif.type != IEEE80211_IF_TYPE_MNTR ||
1576                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
1577                         continue;
1578
1579                 if (prev_dev) {
1580                         skb2 = skb_clone(skb, GFP_ATOMIC);
1581                         if (skb2) {
1582                                 skb2->dev = prev_dev;
1583                                 netif_rx(skb2);
1584                         }
1585                 }
1586
1587                 prev_dev = sdata->dev;
1588                 sdata->dev->stats.rx_packets++;
1589                 sdata->dev->stats.rx_bytes += skb->len;
1590         }
1591
1592         if (prev_dev) {
1593                 skb->dev = prev_dev;
1594                 netif_rx(skb);
1595                 skb = NULL;
1596         } else
1597                 goto out_free_skb;
1598
1599         rx->flags |= IEEE80211_TXRXD_RX_CMNTR_REPORTED;
1600         return;
1601
1602  out_free_skb:
1603         dev_kfree_skb(skb);
1604 }
1605
1606 typedef ieee80211_rx_result (*ieee80211_rx_handler)(struct ieee80211_txrx_data *);
1607 static ieee80211_rx_handler ieee80211_rx_handlers[] =
1608 {
1609         ieee80211_rx_h_if_stats,
1610         ieee80211_rx_h_passive_scan,
1611         ieee80211_rx_h_check,
1612         ieee80211_rx_h_decrypt,
1613         ieee80211_rx_h_sta_process,
1614         ieee80211_rx_h_defragment,
1615         ieee80211_rx_h_ps_poll,
1616         ieee80211_rx_h_michael_mic_verify,
1617         /* this must be after decryption - so header is counted in MPDU mic
1618          * must be before pae and data, so QOS_DATA format frames
1619          * are not passed to user space by these functions
1620          */
1621         ieee80211_rx_h_remove_qos_control,
1622         ieee80211_rx_h_amsdu,
1623         ieee80211_rx_h_data,
1624         ieee80211_rx_h_ctrl,
1625         ieee80211_rx_h_mgmt,
1626         NULL
1627 };
1628
1629 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
1630                                          struct ieee80211_txrx_data *rx,
1631                                          struct sk_buff *skb)
1632 {
1633         ieee80211_rx_handler *handler;
1634         ieee80211_rx_result res = RX_DROP_MONITOR;
1635
1636         rx->skb = skb;
1637         rx->sdata = sdata;
1638         rx->dev = sdata->dev;
1639
1640         for (handler = ieee80211_rx_handlers; *handler != NULL; handler++) {
1641                 res = (*handler)(rx);
1642
1643                 switch (res) {
1644                 case RX_CONTINUE:
1645                         continue;
1646                 case RX_DROP_UNUSABLE:
1647                 case RX_DROP_MONITOR:
1648                         I802_DEBUG_INC(sdata->local->rx_handlers_drop);
1649                         if (rx->sta)
1650                                 rx->sta->rx_dropped++;
1651                         break;
1652                 case RX_QUEUED:
1653                         I802_DEBUG_INC(sdata->local->rx_handlers_queued);
1654                         break;
1655                 }
1656                 break;
1657         }
1658
1659         switch (res) {
1660         case RX_CONTINUE:
1661         case RX_DROP_MONITOR:
1662                 ieee80211_rx_cooked_monitor(rx);
1663                 break;
1664         case RX_DROP_UNUSABLE:
1665                 dev_kfree_skb(rx->skb);
1666                 break;
1667         }
1668 }
1669
1670 /* main receive path */
1671
1672 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
1673                                 u8 *bssid, struct ieee80211_txrx_data *rx,
1674                                 struct ieee80211_hdr *hdr)
1675 {
1676         int multicast = is_multicast_ether_addr(hdr->addr1);
1677
1678         switch (sdata->vif.type) {
1679         case IEEE80211_IF_TYPE_STA:
1680                 if (!bssid)
1681                         return 0;
1682                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1683                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1684                                 return 0;
1685                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1686                 } else if (!multicast &&
1687                            compare_ether_addr(sdata->dev->dev_addr,
1688                                               hdr->addr1) != 0) {
1689                         if (!(sdata->dev->flags & IFF_PROMISC))
1690                                 return 0;
1691                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1692                 }
1693                 break;
1694         case IEEE80211_IF_TYPE_IBSS:
1695                 if (!bssid)
1696                         return 0;
1697                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1698                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1699                                 return 0;
1700                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1701                 } else if (!multicast &&
1702                            compare_ether_addr(sdata->dev->dev_addr,
1703                                               hdr->addr1) != 0) {
1704                         if (!(sdata->dev->flags & IFF_PROMISC))
1705                                 return 0;
1706                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1707                 } else if (!rx->sta)
1708                         rx->sta = ieee80211_ibss_add_sta(sdata->dev, rx->skb,
1709                                                          bssid, hdr->addr2);
1710                 break;
1711         case IEEE80211_IF_TYPE_VLAN:
1712         case IEEE80211_IF_TYPE_AP:
1713                 if (!bssid) {
1714                         if (compare_ether_addr(sdata->dev->dev_addr,
1715                                                hdr->addr1))
1716                                 return 0;
1717                 } else if (!ieee80211_bssid_match(bssid,
1718                                         sdata->dev->dev_addr)) {
1719                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1720                                 return 0;
1721                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1722                 }
1723                 if (sdata->dev == sdata->local->mdev &&
1724                     !(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1725                         /* do not receive anything via
1726                          * master device when not scanning */
1727                         return 0;
1728                 break;
1729         case IEEE80211_IF_TYPE_WDS:
1730                 if (bssid ||
1731                     (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
1732                         return 0;
1733                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
1734                         return 0;
1735                 break;
1736         case IEEE80211_IF_TYPE_MNTR:
1737                 /* take everything */
1738                 break;
1739         case IEEE80211_IF_TYPE_INVALID:
1740                 /* should never get here */
1741                 WARN_ON(1);
1742                 break;
1743         }
1744
1745         return 1;
1746 }
1747
1748 /*
1749  * This is the actual Rx frames handler. as it blongs to Rx path it must
1750  * be called with rcu_read_lock protection.
1751  */
1752 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
1753                                          struct sk_buff *skb,
1754                                          struct ieee80211_rx_status *status,
1755                                          u32 load,
1756                                          struct ieee80211_rate *rate)
1757 {
1758         struct ieee80211_local *local = hw_to_local(hw);
1759         struct ieee80211_sub_if_data *sdata;
1760         struct ieee80211_hdr *hdr;
1761         struct ieee80211_txrx_data rx;
1762         u16 type;
1763         int prepares;
1764         struct ieee80211_sub_if_data *prev = NULL;
1765         struct sk_buff *skb_new;
1766         u8 *bssid;
1767
1768         hdr = (struct ieee80211_hdr *) skb->data;
1769         memset(&rx, 0, sizeof(rx));
1770         rx.skb = skb;
1771         rx.local = local;
1772
1773         rx.u.rx.status = status;
1774         rx.u.rx.load = load;
1775         rx.u.rx.rate = rate;
1776         rx.fc = le16_to_cpu(hdr->frame_control);
1777         type = rx.fc & IEEE80211_FCTL_FTYPE;
1778
1779         if (type == IEEE80211_FTYPE_DATA || type == IEEE80211_FTYPE_MGMT)
1780                 local->dot11ReceivedFragmentCount++;
1781
1782         rx.sta = sta_info_get(local, hdr->addr2);
1783         if (rx.sta) {
1784                 rx.dev = rx.sta->dev;
1785                 rx.sdata = IEEE80211_DEV_TO_SUB_IF(rx.dev);
1786         }
1787
1788         if ((status->flag & RX_FLAG_MMIC_ERROR)) {
1789                 ieee80211_rx_michael_mic_report(local->mdev, hdr, &rx);
1790                 goto end;
1791         }
1792
1793         if (unlikely(local->sta_sw_scanning || local->sta_hw_scanning))
1794                 rx.flags |= IEEE80211_TXRXD_RXIN_SCAN;
1795
1796         ieee80211_parse_qos(&rx);
1797         ieee80211_verify_ip_alignment(&rx);
1798
1799         skb = rx.skb;
1800
1801         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1802                 if (!netif_running(sdata->dev))
1803                         continue;
1804
1805                 if (sdata->vif.type == IEEE80211_IF_TYPE_MNTR)
1806                         continue;
1807
1808                 bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
1809                 rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
1810                 prepares = prepare_for_handlers(sdata, bssid, &rx, hdr);
1811
1812                 if (!prepares)
1813                         continue;
1814
1815                 /*
1816                  * frame is destined for this interface, but if it's not
1817                  * also for the previous one we handle that after the
1818                  * loop to avoid copying the SKB once too much
1819                  */
1820
1821                 if (!prev) {
1822                         prev = sdata;
1823                         continue;
1824                 }
1825
1826                 /*
1827                  * frame was destined for the previous interface
1828                  * so invoke RX handlers for it
1829                  */
1830
1831                 skb_new = skb_copy(skb, GFP_ATOMIC);
1832                 if (!skb_new) {
1833                         if (net_ratelimit())
1834                                 printk(KERN_DEBUG "%s: failed to copy "
1835                                        "multicast frame for %s",
1836                                        wiphy_name(local->hw.wiphy),
1837                                        prev->dev->name);
1838                         continue;
1839                 }
1840                 rx.fc = le16_to_cpu(hdr->frame_control);
1841                 ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
1842                 prev = sdata;
1843         }
1844         if (prev) {
1845                 rx.fc = le16_to_cpu(hdr->frame_control);
1846                 ieee80211_invoke_rx_handlers(prev, &rx, skb);
1847         } else
1848                 dev_kfree_skb(skb);
1849
1850  end:
1851         if (rx.sta)
1852                 sta_info_put(rx.sta);
1853 }
1854
1855 #define SEQ_MODULO 0x1000
1856 #define SEQ_MASK   0xfff
1857
1858 static inline int seq_less(u16 sq1, u16 sq2)
1859 {
1860         return (((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1));
1861 }
1862
1863 static inline u16 seq_inc(u16 sq)
1864 {
1865         return ((sq + 1) & SEQ_MASK);
1866 }
1867
1868 static inline u16 seq_sub(u16 sq1, u16 sq2)
1869 {
1870         return ((sq1 - sq2) & SEQ_MASK);
1871 }
1872
1873
1874 /*
1875  * As it function blongs to Rx path it must be called with
1876  * the proper rcu_read_lock protection for its flow.
1877  */
1878 u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
1879                                 struct tid_ampdu_rx *tid_agg_rx,
1880                                 struct sk_buff *skb, u16 mpdu_seq_num,
1881                                 int bar_req)
1882 {
1883         struct ieee80211_local *local = hw_to_local(hw);
1884         struct ieee80211_rx_status status;
1885         u16 head_seq_num, buf_size;
1886         int index;
1887         u32 pkt_load;
1888         struct ieee80211_supported_band *sband;
1889         struct ieee80211_rate *rate;
1890
1891         buf_size = tid_agg_rx->buf_size;
1892         head_seq_num = tid_agg_rx->head_seq_num;
1893
1894         /* frame with out of date sequence number */
1895         if (seq_less(mpdu_seq_num, head_seq_num)) {
1896                 dev_kfree_skb(skb);
1897                 return 1;
1898         }
1899
1900         /* if frame sequence number exceeds our buffering window size or
1901          * block Ack Request arrived - release stored frames */
1902         if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
1903                 /* new head to the ordering buffer */
1904                 if (bar_req)
1905                         head_seq_num = mpdu_seq_num;
1906                 else
1907                         head_seq_num =
1908                                 seq_inc(seq_sub(mpdu_seq_num, buf_size));
1909                 /* release stored frames up to new head to stack */
1910                 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
1911                         index = seq_sub(tid_agg_rx->head_seq_num,
1912                                 tid_agg_rx->ssn)
1913                                 % tid_agg_rx->buf_size;
1914
1915                         if (tid_agg_rx->reorder_buf[index]) {
1916                                 /* release the reordered frames to stack */
1917                                 memcpy(&status,
1918                                         tid_agg_rx->reorder_buf[index]->cb,
1919                                         sizeof(status));
1920                                 sband = local->hw.wiphy->bands[status.band];
1921                                 rate = &sband->bitrates[status.rate_idx];
1922                                 pkt_load = ieee80211_rx_load_stats(local,
1923                                                 tid_agg_rx->reorder_buf[index],
1924                                                 &status, rate);
1925                                 __ieee80211_rx_handle_packet(hw,
1926                                         tid_agg_rx->reorder_buf[index],
1927                                         &status, pkt_load, rate);
1928                                 tid_agg_rx->stored_mpdu_num--;
1929                                 tid_agg_rx->reorder_buf[index] = NULL;
1930                         }
1931                         tid_agg_rx->head_seq_num =
1932                                 seq_inc(tid_agg_rx->head_seq_num);
1933                 }
1934                 if (bar_req)
1935                         return 1;
1936         }
1937
1938         /* now the new frame is always in the range of the reordering */
1939         /* buffer window */
1940         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
1941                                 % tid_agg_rx->buf_size;
1942         /* check if we already stored this frame */
1943         if (tid_agg_rx->reorder_buf[index]) {
1944                 dev_kfree_skb(skb);
1945                 return 1;
1946         }
1947
1948         /* if arrived mpdu is in the right order and nothing else stored */
1949         /* release it immediately */
1950         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
1951                         tid_agg_rx->stored_mpdu_num == 0) {
1952                 tid_agg_rx->head_seq_num =
1953                         seq_inc(tid_agg_rx->head_seq_num);
1954                 return 0;
1955         }
1956
1957         /* put the frame in the reordering buffer */
1958         tid_agg_rx->reorder_buf[index] = skb;
1959         tid_agg_rx->stored_mpdu_num++;
1960         /* release the buffer until next missing frame */
1961         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
1962                                                 % tid_agg_rx->buf_size;
1963         while (tid_agg_rx->reorder_buf[index]) {
1964                 /* release the reordered frame back to stack */
1965                 memcpy(&status, tid_agg_rx->reorder_buf[index]->cb,
1966                         sizeof(status));
1967                 sband = local->hw.wiphy->bands[status.band];
1968                 rate = &sband->bitrates[status.rate_idx];
1969                 pkt_load = ieee80211_rx_load_stats(local,
1970                                         tid_agg_rx->reorder_buf[index],
1971                                         &status, rate);
1972                 __ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index],
1973                                              &status, pkt_load, rate);
1974                 tid_agg_rx->stored_mpdu_num--;
1975                 tid_agg_rx->reorder_buf[index] = NULL;
1976                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
1977                 index = seq_sub(tid_agg_rx->head_seq_num,
1978                         tid_agg_rx->ssn) % tid_agg_rx->buf_size;
1979         }
1980         return 1;
1981 }
1982
1983 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
1984                                      struct sk_buff *skb)
1985 {
1986         struct ieee80211_hw *hw = &local->hw;
1987         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1988         struct sta_info *sta;
1989         struct tid_ampdu_rx *tid_agg_rx;
1990         u16 fc, sc;
1991         u16 mpdu_seq_num;
1992         u8 ret = 0, *qc;
1993         int tid;
1994
1995         sta = sta_info_get(local, hdr->addr2);
1996         if (!sta)
1997                 return ret;
1998
1999         fc = le16_to_cpu(hdr->frame_control);
2000
2001         /* filter the QoS data rx stream according to
2002          * STA/TID and check if this STA/TID is on aggregation */
2003         if (!WLAN_FC_IS_QOS_DATA(fc))
2004                 goto end_reorder;
2005
2006         qc = skb->data + ieee80211_get_hdrlen(fc) - QOS_CONTROL_LEN;
2007         tid = qc[0] & QOS_CONTROL_TID_MASK;
2008         tid_agg_rx = &(sta->ampdu_mlme.tid_rx[tid]);
2009
2010         if (tid_agg_rx->state != HT_AGG_STATE_OPERATIONAL)
2011                 goto end_reorder;
2012
2013         /* null data frames are excluded */
2014         if (unlikely(fc & IEEE80211_STYPE_NULLFUNC))
2015                 goto end_reorder;
2016
2017         /* new un-ordered ampdu frame - process it */
2018
2019         /* reset session timer */
2020         if (tid_agg_rx->timeout) {
2021                 unsigned long expires =
2022                         jiffies + (tid_agg_rx->timeout / 1000) * HZ;
2023                 mod_timer(&tid_agg_rx->session_timer, expires);
2024         }
2025
2026         /* if this mpdu is fragmented - terminate rx aggregation session */
2027         sc = le16_to_cpu(hdr->seq_ctrl);
2028         if (sc & IEEE80211_SCTL_FRAG) {
2029                 ieee80211_sta_stop_rx_ba_session(sta->dev, sta->addr,
2030                         tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
2031                 ret = 1;
2032                 goto end_reorder;
2033         }
2034
2035         /* according to mpdu sequence number deal with reordering buffer */
2036         mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
2037         ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb,
2038                                                 mpdu_seq_num, 0);
2039 end_reorder:
2040         if (sta)
2041                 sta_info_put(sta);
2042         return ret;
2043 }
2044
2045 /*
2046  * This is the receive path handler. It is called by a low level driver when an
2047  * 802.11 MPDU is received from the hardware.
2048  */
2049 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
2050                     struct ieee80211_rx_status *status)
2051 {
2052         struct ieee80211_local *local = hw_to_local(hw);
2053         u32 pkt_load;
2054         struct ieee80211_rate *rate = NULL;
2055         struct ieee80211_supported_band *sband;
2056
2057         if (status->band < 0 ||
2058             status->band > IEEE80211_NUM_BANDS) {
2059                 WARN_ON(1);
2060                 return;
2061         }
2062
2063         sband = local->hw.wiphy->bands[status->band];
2064
2065         if (!sband ||
2066             status->rate_idx < 0 ||
2067             status->rate_idx >= sband->n_bitrates) {
2068                 WARN_ON(1);
2069                 return;
2070         }
2071
2072         rate = &sband->bitrates[status->rate_idx];
2073
2074         /*
2075          * key references and virtual interfaces are protected using RCU
2076          * and this requires that we are in a read-side RCU section during
2077          * receive processing
2078          */
2079         rcu_read_lock();
2080
2081         /*
2082          * Frames with failed FCS/PLCP checksum are not returned,
2083          * all other frames are returned without radiotap header
2084          * if it was previously present.
2085          * Also, frames with less than 16 bytes are dropped.
2086          */
2087         skb = ieee80211_rx_monitor(local, skb, status, rate);
2088         if (!skb) {
2089                 rcu_read_unlock();
2090                 return;
2091         }
2092
2093         pkt_load = ieee80211_rx_load_stats(local, skb, status, rate);
2094         local->channel_use_raw += pkt_load;
2095
2096         if (!ieee80211_rx_reorder_ampdu(local, skb))
2097                 __ieee80211_rx_handle_packet(hw, skb, status, pkt_load, rate);
2098
2099         rcu_read_unlock();
2100 }
2101 EXPORT_SYMBOL(__ieee80211_rx);
2102
2103 /* This is a version of the rx handler that can be called from hard irq
2104  * context. Post the skb on the queue and schedule the tasklet */
2105 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
2106                           struct ieee80211_rx_status *status)
2107 {
2108         struct ieee80211_local *local = hw_to_local(hw);
2109
2110         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2111
2112         skb->dev = local->mdev;
2113         /* copy status into skb->cb for use by tasklet */
2114         memcpy(skb->cb, status, sizeof(*status));
2115         skb->pkt_type = IEEE80211_RX_MSG;
2116         skb_queue_tail(&local->skb_queue, skb);
2117         tasklet_schedule(&local->tasklet);
2118 }
2119 EXPORT_SYMBOL(ieee80211_rx_irqsafe);