err.no 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 "ieee80211_led.h"
  23 #include "wep.h"
  24 #include "wpa.h"
  25 #include "tkip.h"
  26 #include "wme.h"
  27
  28 u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
  29                                 struct tid_ampdu_rx *tid_agg_rx,
  30                                 struct sk_buff *skb, u16 mpdu_seq_num,
  31                                 int bar_req);
  32 /*
  33  * monitor mode reception
  34  *
  35  * This function cleans up the SKB, i.e. it removes all the stuff
  36  * only useful for monitoring.
  37  */
  38 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
  39                                            struct sk_buff *skb,
  40                                            int rtap_len)
  41 {
  42         skb_pull(skb, rtap_len);
  43
  44         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
  45                 if (likely(skb->len > FCS_LEN))
  46                         skb_trim(skb, skb->len - FCS_LEN);
  47                 else {
  48                         /* driver bug */
  49                         WARN_ON(1);
  50                         dev_kfree_skb(skb);
  51                         skb = NULL;
  52                 }
  53         }
  54
  55         return skb;
  56 }
  57
  58 static inline int should_drop_frame(struct ieee80211_rx_status *status,
  59                                     struct sk_buff *skb,
  60                                     int present_fcs_len,
  61                                     int radiotap_len)
  62 {
  63         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
  64
  65         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
  66                 return 1;
  67         if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len))
  68                 return 1;
  69         if (((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_FTYPE)) ==
  70                         cpu_to_le16(IEEE80211_FTYPE_CTL)) &&
  71             ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE)) !=
  72                         cpu_to_le16(IEEE80211_STYPE_PSPOLL)) &&
  73             ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE)) !=
  74                         cpu_to_le16(IEEE80211_STYPE_BACK_REQ)))
  75                 return 1;
  76         return 0;
  77 }
  78
  79 /*
  80  * This function copies a received frame to all monitor interfaces and
  81  * returns a cleaned-up SKB that no longer includes the FCS nor the
  82  * radiotap header the driver might have added.
  83  */
  84 static struct sk_buff *
  85 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
  86                      struct ieee80211_rx_status *status,
  87                      struct ieee80211_rate *rate)
  88 {
  89         struct ieee80211_sub_if_data *sdata;
  90         int needed_headroom = 0;
  91         struct ieee80211_radiotap_header *rthdr;
  92         __le64 *rttsft = NULL;
  93         struct ieee80211_rtap_fixed_data {
  94                 u8 flags;
  95                 u8 rate;
  96                 __le16 chan_freq;
  97                 __le16 chan_flags;
  98                 u8 antsignal;
  99                 u8 padding_for_rxflags;
 100                 __le16 rx_flags;
 101         } __attribute__ ((packed)) *rtfixed;
 102         struct sk_buff *skb, *skb2;
 103         struct net_device *prev_dev = NULL;
 104         int present_fcs_len = 0;
 105         int rtap_len = 0;
 106
 107         /*
 108          * First, we may need to make a copy of the skb because
 109          *  (1) we need to modify it for radiotap (if not present), and
 110          *  (2) the other RX handlers will modify the skb we got.
 111          *
 112          * We don't need to, of course, if we aren't going to return
 113          * the SKB because it has a bad FCS/PLCP checksum.
 114          */
 115         if (status->flag & RX_FLAG_RADIOTAP)
 116                 rtap_len = ieee80211_get_radiotap_len(origskb->data);
 117         else
 118                 /* room for radiotap header, always present fields and TSFT */
 119                 needed_headroom = sizeof(*rthdr) + sizeof(*rtfixed) + 8;
 120
 121         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 122                 present_fcs_len = FCS_LEN;
 123
 124         if (!local->monitors) {
 125                 if (should_drop_frame(status, origskb, present_fcs_len,
 126                                       rtap_len)) {
 127                         dev_kfree_skb(origskb);
 128                         return NULL;
 129                 }
 130
 131                 return remove_monitor_info(local, origskb, rtap_len);
 132         }
 133
 134         if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) {
 135                 /* only need to expand headroom if necessary */
 136                 skb = origskb;
 137                 origskb = NULL;
 138
 139                 /*
 140                  * This shouldn't trigger often because most devices have an
 141                  * RX header they pull before we get here, and that should
 142                  * be big enough for our radiotap information. We should
 143                  * probably export the length to drivers so that we can have
 144                  * them allocate enough headroom to start with.
 145                  */
 146                 if (skb_headroom(skb) < needed_headroom &&
 147                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
 148                         dev_kfree_skb(skb);
 149                         return NULL;
 150                 }
 151         } else {
 152                 /*
 153                  * Need to make a copy and possibly remove radiotap header
 154                  * and FCS from the original.
 155                  */
 156                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
 157
 158                 origskb = remove_monitor_info(local, origskb, rtap_len);
 159
 160                 if (!skb)
 161                         return origskb;
 162         }
 163
 164         /* if necessary, prepend radiotap information */
 165         if (!(status->flag & RX_FLAG_RADIOTAP)) {
 166                 rtfixed = (void *) skb_push(skb, sizeof(*rtfixed));
 167                 rtap_len = sizeof(*rthdr) + sizeof(*rtfixed);
 168                 if (status->flag & RX_FLAG_TSFT) {
 169                         rttsft = (void *) skb_push(skb, sizeof(*rttsft));
 170                         rtap_len += 8;
 171                 }
 172                 rthdr = (void *) skb_push(skb, sizeof(*rthdr));
 173                 memset(rthdr, 0, sizeof(*rthdr));
 174                 memset(rtfixed, 0, sizeof(*rtfixed));
 175                 rthdr->it_present =
 176                         cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 177                                     (1 << IEEE80211_RADIOTAP_RATE) |
 178                                     (1 << IEEE80211_RADIOTAP_CHANNEL) |
 179                                     (1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL) |
 180                                     (1 << IEEE80211_RADIOTAP_RX_FLAGS));
 181                 rtfixed->flags = 0;
 182                 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 183                         rtfixed->flags |= IEEE80211_RADIOTAP_F_FCS;
 184
 185                 if (rttsft) {
 186                         *rttsft = cpu_to_le64(status->mactime);
 187                         rthdr->it_present |=
 188                                 cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
 189                 }
 190
 191                 /* FIXME: when radiotap gets a 'bad PLCP' flag use it here */
 192                 rtfixed->rx_flags = 0;
 193                 if (status->flag &
 194                     (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 195                         rtfixed->rx_flags |=
 196                                 cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS);
 197
 198                 rtfixed->rate = rate->bitrate / 5;
 199
 200                 rtfixed->chan_freq = cpu_to_le16(status->freq);
 201
 202                 if (status->band == IEEE80211_BAND_5GHZ)
 203                         rtfixed->chan_flags =
 204                                 cpu_to_le16(IEEE80211_CHAN_OFDM |
 205                                             IEEE80211_CHAN_5GHZ);
 206                 else
 207                         rtfixed->chan_flags =
 208                                 cpu_to_le16(IEEE80211_CHAN_DYN |
 209                                             IEEE80211_CHAN_2GHZ);
 210
 211                 rtfixed->antsignal = status->ssi;
 212                 rthdr->it_len = cpu_to_le16(rtap_len);
 213         }
 214
 215         skb_reset_mac_header(skb);
 216         skb->ip_summed = CHECKSUM_UNNECESSARY;
 217         skb->pkt_type = PACKET_OTHERHOST;
 218         skb->protocol = htons(ETH_P_802_2);
 219
 220         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 221                 if (!netif_running(sdata->dev))
 222                         continue;
 223
 224                 if (sdata->vif.type != IEEE80211_IF_TYPE_MNTR)
 225                         continue;
 226
 227                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
 228                         continue;
 229
 230                 if (prev_dev) {
 231                         skb2 = skb_clone(skb, GFP_ATOMIC);
 232                         if (skb2) {
 233                                 skb2->dev = prev_dev;
 234                                 netif_rx(skb2);
 235                         }
 236                 }
 237
 238                 prev_dev = sdata->dev;
 239                 sdata->dev->stats.rx_packets++;
 240                 sdata->dev->stats.rx_bytes += skb->len;
 241         }
 242
 243         if (prev_dev) {
 244                 skb->dev = prev_dev;
 245                 netif_rx(skb);
 246         } else
 247                 dev_kfree_skb(skb);
 248
 249         return origskb;
 250 }
 251
 252
 253 static void ieee80211_parse_qos(struct ieee80211_txrx_data *rx)
 254 {
 255         u8 *data = rx->skb->data;
 256         int tid;
 257
 258         /* does the frame have a qos control field? */
 259         if (WLAN_FC_IS_QOS_DATA(rx->fc)) {
 260                 u8 *qc = data + ieee80211_get_hdrlen(rx->fc) - QOS_CONTROL_LEN;
 261                 /* frame has qos control */
 262                 tid = qc[0] & QOS_CONTROL_TID_MASK;
 263                 if (qc[0] & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
 264                         rx->flags |= IEEE80211_TXRXD_RX_AMSDU;
 265                 else
 266                         rx->flags &= ~IEEE80211_TXRXD_RX_AMSDU;
 267         } else {
 268                 if (unlikely((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT)) {
 269                         /* Separate TID for management frames */
 270                         tid = NUM_RX_DATA_QUEUES - 1;
 271                 } else {
 272                         /* no qos control present */
 273                         tid = 0; /* 802.1d - Best Effort */
 274                 }
 275         }
 276
 277         I802_DEBUG_INC(rx->local->wme_rx_queue[tid]);
 278         /* only a debug counter, sta might not be assigned properly yet */
 279         if (rx->sta)
 280                 I802_DEBUG_INC(rx->sta->wme_rx_queue[tid]);
 281
 282         rx->u.rx.queue = tid;
 283         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 284          * For now, set skb->priority to 0 for other cases. */
 285         rx->skb->priority = (tid > 7) ? 0 : tid;
 286 }
 287
 288 static void ieee80211_verify_ip_alignment(struct ieee80211_txrx_data *rx)
 289 {
 290 #ifdef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
 291         int hdrlen;
 292
 293         if (!WLAN_FC_DATA_PRESENT(rx->fc))
 294                 return;
 295
 296         /*
 297          * Drivers are required to align the payload data in a way that
 298          * guarantees that the contained IP header is aligned to a four-
 299          * byte boundary. In the case of regular frames, this simply means
 300          * aligning the payload to a four-byte boundary (because either
 301          * the IP header is directly contained, or IV/RFC1042 headers that
 302          * have a length divisible by four are in front of it.
 303          *
 304          * With A-MSDU frames, however, the payload data address must
 305          * yield two modulo four because there are 14-byte 802.3 headers
 306          * within the A-MSDU frames that push the IP header further back
 307          * to a multiple of four again. Thankfully, the specs were sane
 308          * enough this time around to require padding each A-MSDU subframe
 309          * to a length that is a multiple of four.
 310          *
 311          * Padding like atheros hardware adds which is inbetween the 802.11
 312          * header and the payload is not supported, the driver is required
 313          * to move the 802.11 header further back in that case.
 314          */
 315         hdrlen = ieee80211_get_hdrlen(rx->fc);
 316         if (rx->flags & IEEE80211_TXRXD_RX_AMSDU)
 317                 hdrlen += ETH_HLEN;
 318         WARN_ON_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3);
 319 #endif
 320 }
 321
 322
 323 static u32 ieee80211_rx_load_stats(struct ieee80211_local *local,
 324                                    struct sk_buff *skb,
 325                                    struct ieee80211_rx_status *status,
 326                                    struct ieee80211_rate *rate)
 327 {
 328         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 329         u32 load = 0, hdrtime;
 330
 331         /* Estimate total channel use caused by this frame */
 332
 333         /* 1 bit at 1 Mbit/s takes 1 usec; in channel_use values,
 334          * 1 usec = 1/8 * (1080 / 10) = 13.5 */
 335
 336         if (status->band == IEEE80211_BAND_5GHZ ||
 337             (status->band == IEEE80211_BAND_5GHZ &&
 338              rate->flags & IEEE80211_RATE_ERP_G))
 339                 hdrtime = CHAN_UTIL_HDR_SHORT;
 340         else
 341                 hdrtime = CHAN_UTIL_HDR_LONG;
 342
 343         load = hdrtime;
 344         if (!is_multicast_ether_addr(hdr->addr1))
 345                 load += hdrtime;
 346
 347         /* TODO: optimise again */
 348         load += skb->len * CHAN_UTIL_RATE_LCM / rate->bitrate;
 349
 350         /* Divide channel_use by 8 to avoid wrapping around the counter */
 351         load >>= CHAN_UTIL_SHIFT;
 352
 353         return load;
 354 }
 355
 356 /* rx handlers */
 357
 358 static ieee80211_rx_result
 359 ieee80211_rx_h_if_stats(struct ieee80211_txrx_data *rx)
 360 {
 361         if (rx->sta)
 362                 rx->sta->channel_use_raw += rx->u.rx.load;
 363         rx->sdata->channel_use_raw += rx->u.rx.load;
 364         return RX_CONTINUE;
 365 }
 366
 367 static ieee80211_rx_result
 368 ieee80211_rx_h_passive_scan(struct ieee80211_txrx_data *rx)
 369 {
 370         struct ieee80211_local *local = rx->local;
 371         struct sk_buff *skb = rx->skb;
 372
 373         if (unlikely(local->sta_hw_scanning))
 374                 return ieee80211_sta_rx_scan(rx->dev, skb, rx->u.rx.status);
 375
 376         if (unlikely(local->sta_sw_scanning)) {
 377                 /* drop all the other packets during a software scan anyway */
 378                 if (ieee80211_sta_rx_scan(rx->dev, skb, rx->u.rx.status)
 379                     != RX_QUEUED)
 380                         dev_kfree_skb(skb);
 381                 return RX_QUEUED;
 382         }
 383
 384         if (unlikely(rx->flags & IEEE80211_TXRXD_RXIN_SCAN)) {
 385                 /* scanning finished during invoking of handlers */
 386                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
 387                 return RX_DROP_UNUSABLE;
 388         }
 389
 390         return RX_CONTINUE;
 391 }
 392
 393 static ieee80211_rx_result
 394 ieee80211_rx_h_check(struct ieee80211_txrx_data *rx)
 395 {
 396         struct ieee80211_hdr *hdr;
 397         hdr = (struct ieee80211_hdr *) rx->skb->data;
 398
 399         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 400         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 401                 if (unlikely(rx->fc & IEEE80211_FCTL_RETRY &&
 402                              rx->sta->last_seq_ctrl[rx->u.rx.queue] ==
 403                              hdr->seq_ctrl)) {
 404                         if (rx->flags & IEEE80211_TXRXD_RXRA_MATCH) {
 405                                 rx->local->dot11FrameDuplicateCount++;
 406                                 rx->sta->num_duplicates++;
 407                         }
 408                         return RX_DROP_MONITOR;
 409                 } else
 410                         rx->sta->last_seq_ctrl[rx->u.rx.queue] = hdr->seq_ctrl;
 411         }
 412
 413         if (unlikely(rx->skb->len < 16)) {
 414                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 415                 return RX_DROP_MONITOR;
 416         }
 417
 418         /* Drop disallowed frame classes based on STA auth/assoc state;
 419          * IEEE 802.11, Chap 5.5.
 420          *
 421          * 80211.o does filtering only based on association state, i.e., it
 422          * drops Class 3 frames from not associated stations. hostapd sends
 423          * deauth/disassoc frames when needed. In addition, hostapd is
 424          * responsible for filtering on both auth and assoc states.
 425          */
 426         if (unlikely(((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA ||
 427                       ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_CTL &&
 428                        (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PSPOLL)) &&
 429                      rx->sdata->vif.type != IEEE80211_IF_TYPE_IBSS &&
 430                      (!rx->sta || !(rx->sta->flags & WLAN_STA_ASSOC)))) {
 431                 if ((!(rx->fc & IEEE80211_FCTL_FROMDS) &&
 432                      !(rx->fc & IEEE80211_FCTL_TODS) &&
 433                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA)
 434                     || !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
 435                         /* Drop IBSS frames and frames for other hosts
 436                          * silently. */
 437                         return RX_DROP_MONITOR;
 438                 }
 439
 440                 return RX_DROP_MONITOR;
 441         }
 442
 443         return RX_CONTINUE;
 444 }
 445
 446
 447 static ieee80211_rx_result
 448 ieee80211_rx_h_decrypt(struct ieee80211_txrx_data *rx)
 449 {
 450         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 451         int keyidx;
 452         int hdrlen;
 453         ieee80211_rx_result result = RX_DROP_UNUSABLE;
 454         struct ieee80211_key *stakey = NULL;
 455
 456         /*
 457          * Key selection 101
 458          *
 459          * There are three types of keys:
 460          *  - GTK (group keys)
 461          *  - PTK (pairwise keys)
 462          *  - STK (station-to-station pairwise keys)
 463          *
 464          * When selecting a key, we have to distinguish between multicast
 465          * (including broadcast) and unicast frames, the latter can only
 466          * use PTKs and STKs while the former always use GTKs. Unless, of
 467          * course, actual WEP keys ("pre-RSNA") are used, then unicast
 468          * frames can also use key indizes like GTKs. Hence, if we don't
 469          * have a PTK/STK we check the key index for a WEP key.
 470          *
 471          * Note that in a regular BSS, multicast frames are sent by the
 472          * AP only, associated stations unicast the frame to the AP first
 473          * which then multicasts it on their behalf.
 474          *
 475          * There is also a slight problem in IBSS mode: GTKs are negotiated
 476          * with each station, that is something we don't currently handle.
 477          * The spec seems to expect that one negotiates the same key with
 478          * every station but there's no such requirement; VLANs could be
 479          * possible.
 480          */
 481
 482         if (!(rx->fc & IEEE80211_FCTL_PROTECTED))
 483                 return RX_CONTINUE;
 484
 485         /*
 486          * No point in finding a key and decrypting if the frame is neither
 487          * addressed to us nor a multicast frame.
 488          */
 489         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 490                 return RX_CONTINUE;
 491
 492         if (rx->sta)
 493                 stakey = rcu_dereference(rx->sta->key);
 494
 495         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
 496                 rx->key = stakey;
 497         } else {
 498                 /*
 499                  * The device doesn't give us the IV so we won't be
 500                  * able to look up the key. That's ok though, we
 501                  * don't need to decrypt the frame, we just won't
 502                  * be able to keep statistics accurate.
 503                  * Except for key threshold notifications, should
 504                  * we somehow allow the driver to tell us which key
 505                  * the hardware used if this flag is set?
 506                  */
 507                 if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) &&
 508                     (rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED))
 509                         return RX_CONTINUE;
 510
 511                 hdrlen = ieee80211_get_hdrlen(rx->fc);
 512
 513                 if (rx->skb->len < 8 + hdrlen)
 514                         return RX_DROP_UNUSABLE; /* TODO: count this? */
 515
 516                 /*
 517                  * no need to call ieee80211_wep_get_keyidx,
 518                  * it verifies a bunch of things we've done already
 519                  */
 520                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
 521
 522                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
 523
 524                 /*
 525                  * RSNA-protected unicast frames should always be sent with
 526                  * pairwise or station-to-station keys, but for WEP we allow
 527                  * using a key index as well.
 528                  */
 529                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
 530                     !is_multicast_ether_addr(hdr->addr1))
 531                         rx->key = NULL;
 532         }
 533
 534         if (rx->key) {
 535                 rx->key->tx_rx_count++;
 536                 /* TODO: add threshold stuff again */
 537         } else {
 538 #ifdef CONFIG_MAC80211_DEBUG
 539                 if (net_ratelimit())
 540                         printk(KERN_DEBUG "%s: RX protected frame,"
 541                                " but have no key\n", rx->dev->name);
 542 #endif /* CONFIG_MAC80211_DEBUG */
 543                 return RX_DROP_MONITOR;
 544         }
 545
 546         /* Check for weak IVs if possible */
 547         if (rx->sta && rx->key->conf.alg == ALG_WEP &&
 548             ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) &&
 549             (!(rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED) ||
 550              !(rx->u.rx.status->flag & RX_FLAG_DECRYPTED)) &&
 551             ieee80211_wep_is_weak_iv(rx->skb, rx->key))
 552                 rx->sta->wep_weak_iv_count++;
 553
 554         switch (rx->key->conf.alg) {
 555         case ALG_WEP:
 556                 result = ieee80211_crypto_wep_decrypt(rx);
 557                 break;
 558         case ALG_TKIP:
 559                 result = ieee80211_crypto_tkip_decrypt(rx);
 560                 break;
 561         case ALG_CCMP:
 562                 result = ieee80211_crypto_ccmp_decrypt(rx);
 563                 break;
 564         }
 565
 566         /* either the frame has been decrypted or will be dropped */
 567         rx->u.rx.status->flag |= RX_FLAG_DECRYPTED;
 568
 569         return result;
 570 }
 571
 572 static void ap_sta_ps_start(struct net_device *dev, struct sta_info *sta)
 573 {
 574         struct ieee80211_sub_if_data *sdata;
 575         DECLARE_MAC_BUF(mac);
 576
 577         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 578
 579         if (sdata->bss)
 580                 atomic_inc(&sdata->bss->num_sta_ps);
 581         sta->flags |= WLAN_STA_PS;
 582         sta->flags &= ~WLAN_STA_PSPOLL;
 583 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 584         printk(KERN_DEBUG "%s: STA %s aid %d enters power save mode\n",
 585                dev->name, print_mac(mac, sta->addr), sta->aid);
 586 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 587 }
 588
 589 static int ap_sta_ps_end(struct net_device *dev, struct sta_info *sta)
 590 {
 591         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 592         struct sk_buff *skb;
 593         int sent = 0;
 594         struct ieee80211_sub_if_data *sdata;
 595         struct ieee80211_tx_packet_data *pkt_data;
 596         DECLARE_MAC_BUF(mac);
 597
 598         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 599
 600         if (sdata->bss)
 601                 atomic_dec(&sdata->bss->num_sta_ps);
 602
 603         sta->flags &= ~(WLAN_STA_PS | WLAN_STA_PSPOLL);
 604
 605         if (!skb_queue_empty(&sta->ps_tx_buf))
 606                 sta_info_clear_tim_bit(sta);
 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
 613         /* Send all buffered frames to the station */
 614         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
 615                 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 616                 sent++;
 617                 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
 618                 dev_queue_xmit(skb);
 619         }
 620         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
 621                 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 622                 local->total_ps_buffered--;
 623                 sent++;
 624 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 625                 printk(KERN_DEBUG "%s: STA %s aid %d send PS frame "
 626                        "since STA not sleeping anymore\n", dev->name,
 627                        print_mac(mac, sta->addr), sta->aid);
 628 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 629                 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
 630                 dev_queue_xmit(skb);
 631         }
 632
 633         return sent;
 634 }
 635
 636 static ieee80211_rx_result
 637 ieee80211_rx_h_sta_process(struct ieee80211_txrx_data *rx)
 638 {
 639         struct sta_info *sta = rx->sta;
 640         struct net_device *dev = rx->dev;
 641         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 642
 643         if (!sta)
 644                 return RX_CONTINUE;
 645
 646         /* Update last_rx only for IBSS packets which are for the current
 647          * BSSID to avoid keeping the current IBSS network alive in cases where
 648          * other STAs are using different BSSID. */
 649         if (rx->sdata->vif.type == IEEE80211_IF_TYPE_IBSS) {
 650                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
 651                                                 IEEE80211_IF_TYPE_IBSS);
 652                 if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0)
 653                         sta->last_rx = jiffies;
 654         } else
 655         if (!is_multicast_ether_addr(hdr->addr1) ||
 656             rx->sdata->vif.type == IEEE80211_IF_TYPE_STA) {
 657                 /* Update last_rx only for unicast frames in order to prevent
 658                  * the Probe Request frames (the only broadcast frames from a
 659                  * STA in infrastructure mode) from keeping a connection alive.
 660                  */
 661                 sta->last_rx = jiffies;
 662         }
 663
 664         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 665                 return RX_CONTINUE;
 666
 667         sta->rx_fragments++;
 668         sta->rx_bytes += rx->skb->len;
 669         sta->last_rssi = rx->u.rx.status->ssi;
 670         sta->last_signal = rx->u.rx.status->signal;
 671         sta->last_noise = rx->u.rx.status->noise;
 672
 673         if (!(rx->fc & IEEE80211_FCTL_MOREFRAGS)) {
 674                 /* Change STA power saving mode only in the end of a frame
 675                  * exchange sequence */
 676                 if ((sta->flags & WLAN_STA_PS) && !(rx->fc & IEEE80211_FCTL_PM))
 677                         rx->u.rx.sent_ps_buffered += ap_sta_ps_end(dev, sta);
 678                 else if (!(sta->flags & WLAN_STA_PS) &&
 679                          (rx->fc & IEEE80211_FCTL_PM))
 680                         ap_sta_ps_start(dev, sta);
 681         }
 682
 683         /* Drop data::nullfunc frames silently, since they are used only to
 684          * control station power saving mode. */
 685         if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 686             (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_NULLFUNC) {
 687                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
 688                 /* Update counter and free packet here to avoid counting this
 689                  * as a dropped packed. */
 690                 sta->rx_packets++;
 691                 dev_kfree_skb(rx->skb);
 692                 return RX_QUEUED;
 693         }
 694
 695         return RX_CONTINUE;
 696 } /* ieee80211_rx_h_sta_process */
 697
 698 static inline struct ieee80211_fragment_entry *
 699 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
 700                          unsigned int frag, unsigned int seq, int rx_queue,
 701                          struct sk_buff **skb)
 702 {
 703         struct ieee80211_fragment_entry *entry;
 704         int idx;
 705
 706         idx = sdata->fragment_next;
 707         entry = &sdata->fragments[sdata->fragment_next++];
 708         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
 709                 sdata->fragment_next = 0;
 710
 711         if (!skb_queue_empty(&entry->skb_list)) {
 712 #ifdef CONFIG_MAC80211_DEBUG
 713                 struct ieee80211_hdr *hdr =
 714                         (struct ieee80211_hdr *) entry->skb_list.next->data;
 715                 DECLARE_MAC_BUF(mac);
 716                 DECLARE_MAC_BUF(mac2);
 717                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
 718                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
 719                        "addr1=%s addr2=%s\n",
 720                        sdata->dev->name, idx,
 721                        jiffies - entry->first_frag_time, entry->seq,
 722                        entry->last_frag, print_mac(mac, hdr->addr1),
 723                        print_mac(mac2, hdr->addr2));
 724 #endif /* CONFIG_MAC80211_DEBUG */
 725                 __skb_queue_purge(&entry->skb_list);
 726         }
 727
 728         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
 729         *skb = NULL;
 730         entry->first_frag_time = jiffies;
 731         entry->seq = seq;
 732         entry->rx_queue = rx_queue;
 733         entry->last_frag = frag;
 734         entry->ccmp = 0;
 735         entry->extra_len = 0;
 736
 737         return entry;
 738 }
 739
 740 static inline struct ieee80211_fragment_entry *
 741 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
 742                           u16 fc, unsigned int frag, unsigned int seq,
 743                           int rx_queue, struct ieee80211_hdr *hdr)
 744 {
 745         struct ieee80211_fragment_entry *entry;
 746         int i, idx;
 747
 748         idx = sdata->fragment_next;
 749         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
 750                 struct ieee80211_hdr *f_hdr;
 751                 u16 f_fc;
 752
 753                 idx--;
 754                 if (idx < 0)
 755                         idx = IEEE80211_FRAGMENT_MAX - 1;
 756
 757                 entry = &sdata->fragments[idx];
 758                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
 759                     entry->rx_queue != rx_queue ||
 760                     entry->last_frag + 1 != frag)
 761                         continue;
 762
 763                 f_hdr = (struct ieee80211_hdr *) entry->skb_list.next->data;
 764                 f_fc = le16_to_cpu(f_hdr->frame_control);
 765
 766                 if ((fc & IEEE80211_FCTL_FTYPE) != (f_fc & IEEE80211_FCTL_FTYPE) ||
 767                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
 768                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
 769                         continue;
 770
 771                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
 772                         __skb_queue_purge(&entry->skb_list);
 773                         continue;
 774                 }
 775                 return entry;
 776         }
 777
 778         return NULL;
 779 }
 780
 781 static ieee80211_rx_result
 782 ieee80211_rx_h_defragment(struct ieee80211_txrx_data *rx)
 783 {
 784         struct ieee80211_hdr *hdr;
 785         u16 sc;
 786         unsigned int frag, seq;
 787         struct ieee80211_fragment_entry *entry;
 788         struct sk_buff *skb;
 789         DECLARE_MAC_BUF(mac);
 790
 791         hdr = (struct ieee80211_hdr *) rx->skb->data;
 792         sc = le16_to_cpu(hdr->seq_ctrl);
 793         frag = sc & IEEE80211_SCTL_FRAG;
 794
 795         if (likely((!(rx->fc & IEEE80211_FCTL_MOREFRAGS) && frag == 0) ||
 796                    (rx->skb)->len < 24 ||
 797                    is_multicast_ether_addr(hdr->addr1))) {
 798                 /* not fragmented */
 799                 goto out;
 800         }
 801         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
 802
 803         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
 804
 805         if (frag == 0) {
 806                 /* This is the first fragment of a new frame. */
 807                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
 808                                                  rx->u.rx.queue, &(rx->skb));
 809                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
 810                     (rx->fc & IEEE80211_FCTL_PROTECTED)) {
 811                         /* Store CCMP PN so that we can verify that the next
 812                          * fragment has a sequential PN value. */
 813                         entry->ccmp = 1;
 814                         memcpy(entry->last_pn,
 815                                rx->key->u.ccmp.rx_pn[rx->u.rx.queue],
 816                                CCMP_PN_LEN);
 817                 }
 818                 return RX_QUEUED;
 819         }
 820
 821         /* This is a fragment for a frame that should already be pending in
 822          * fragment cache. Add this fragment to the end of the pending entry.
 823          */
 824         entry = ieee80211_reassemble_find(rx->sdata, rx->fc, frag, seq,
 825                                           rx->u.rx.queue, hdr);
 826         if (!entry) {
 827                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 828                 return RX_DROP_MONITOR;
 829         }
 830
 831         /* Verify that MPDUs within one MSDU have sequential PN values.
 832          * (IEEE 802.11i, 8.3.3.4.5) */
 833         if (entry->ccmp) {
 834                 int i;
 835                 u8 pn[CCMP_PN_LEN], *rpn;
 836                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
 837                         return RX_DROP_UNUSABLE;
 838                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
 839                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
 840                         pn[i]++;
 841                         if (pn[i])
 842                                 break;
 843                 }
 844                 rpn = rx->key->u.ccmp.rx_pn[rx->u.rx.queue];
 845                 if (memcmp(pn, rpn, CCMP_PN_LEN) != 0) {
 846                         if (net_ratelimit())
 847                                 printk(KERN_DEBUG "%s: defrag: CCMP PN not "
 848                                        "sequential A2=%s"
 849                                        " PN=%02x%02x%02x%02x%02x%02x "
 850                                        "(expected %02x%02x%02x%02x%02x%02x)\n",
 851                                        rx->dev->name, print_mac(mac, hdr->addr2),
 852                                        rpn[0], rpn[1], rpn[2], rpn[3], rpn[4],
 853                                        rpn[5], pn[0], pn[1], pn[2], pn[3],
 854                                        pn[4], pn[5]);
 855                         return RX_DROP_UNUSABLE;
 856                 }
 857                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
 858         }
 859
 860         skb_pull(rx->skb, ieee80211_get_hdrlen(rx->fc));
 861         __skb_queue_tail(&entry->skb_list, rx->skb);
 862         entry->last_frag = frag;
 863         entry->extra_len += rx->skb->len;
 864         if (rx->fc & IEEE80211_FCTL_MOREFRAGS) {
 865                 rx->skb = NULL;
 866                 return RX_QUEUED;
 867         }
 868
 869         rx->skb = __skb_dequeue(&entry->skb_list);
 870         if (skb_tailroom(rx->skb) < entry->extra_len) {
 871                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
 872                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
 873                                               GFP_ATOMIC))) {
 874                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 875                         __skb_queue_purge(&entry->skb_list);
 876                         return RX_DROP_UNUSABLE;
 877                 }
 878         }
 879         while ((skb = __skb_dequeue(&entry->skb_list))) {
 880                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
 881                 dev_kfree_skb(skb);
 882         }
 883
 884         /* Complete frame has been reassembled - process it now */
 885         rx->flags |= IEEE80211_TXRXD_FRAGMENTED;
 886
 887  out:
 888         if (rx->sta)
 889                 rx->sta->rx_packets++;
 890         if (is_multicast_ether_addr(hdr->addr1))
 891                 rx->local->dot11MulticastReceivedFrameCount++;
 892         else
 893                 ieee80211_led_rx(rx->local);
 894         return RX_CONTINUE;
 895 }
 896
 897 static ieee80211_rx_result
 898 ieee80211_rx_h_ps_poll(struct ieee80211_txrx_data *rx)
 899 {
 900         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
 901         struct sk_buff *skb;
 902         int no_pending_pkts;
 903         DECLARE_MAC_BUF(mac);
 904
 905         if (likely(!rx->sta ||
 906                    (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL ||
 907                    (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PSPOLL ||
 908                    !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)))
 909                 return RX_CONTINUE;
 910
 911         if ((sdata->vif.type != IEEE80211_IF_TYPE_AP) &&
 912             (sdata->vif.type != IEEE80211_IF_TYPE_VLAN))
 913                 return RX_DROP_UNUSABLE;
 914
 915         skb = skb_dequeue(&rx->sta->tx_filtered);
 916         if (!skb) {
 917                 skb = skb_dequeue(&rx->sta->ps_tx_buf);
 918                 if (skb)
 919                         rx->local->total_ps_buffered--;
 920         }
 921         no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
 922                 skb_queue_empty(&rx->sta->ps_tx_buf);
 923
 924         if (skb) {
 925                 struct ieee80211_hdr *hdr =
 926                         (struct ieee80211_hdr *) skb->data;
 927
 928                 /*
 929                  * Tell TX path to send one frame even though the STA may
 930                  * still remain is PS mode after this frame exchange.
 931                  */
 932                 rx->sta->flags |= WLAN_STA_PSPOLL;
 933
 934 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 935                 printk(KERN_DEBUG "STA %s aid %d: PS Poll (entries after %d)\n",
 936                        print_mac(mac, rx->sta->addr), rx->sta->aid,
 937                        skb_queue_len(&rx->sta->ps_tx_buf));
 938 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 939
 940                 /* Use MoreData flag to indicate whether there are more
 941                  * buffered frames for this STA */
 942                 if (no_pending_pkts)
 943                         hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
 944                 else
 945                         hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
 946
 947                 dev_queue_xmit(skb);
 948
 949                 if (no_pending_pkts)
 950                         sta_info_clear_tim_bit(rx->sta);
 951 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 952         } else if (!rx->u.rx.sent_ps_buffered) {
 953                 /*
 954                  * FIXME: This can be the result of a race condition between
 955                  *        us expiring a frame and the station polling for it.
 956                  *        Should we send it a null-func frame indicating we
 957                  *        have nothing buffered for it?
 958                  */
 959                 printk(KERN_DEBUG "%s: STA %s sent PS Poll even "
 960                        "though there is no buffered frames for it\n",
 961                        rx->dev->name, print_mac(mac, rx->sta->addr));
 962 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 963         }
 964
 965         /* Free PS Poll skb here instead of returning RX_DROP that would
 966          * count as an dropped frame. */
 967         dev_kfree_skb(rx->skb);
 968
 969         return RX_QUEUED;
 970 }
 971
 972 static ieee80211_rx_result
 973 ieee80211_rx_h_remove_qos_control(struct ieee80211_txrx_data *rx)
 974 {
 975         u16 fc = rx->fc;
 976         u8 *data = rx->skb->data;
 977         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) data;
 978
 979         if (!WLAN_FC_IS_QOS_DATA(fc))
 980                 return RX_CONTINUE;
 981
 982         /* remove the qos control field, update frame type and meta-data */
 983         memmove(data + 2, data, ieee80211_get_hdrlen(fc) - 2);
 984         hdr = (struct ieee80211_hdr *) skb_pull(rx->skb, 2);
 985         /* change frame type to non QOS */
 986         rx->fc = fc &= ~IEEE80211_STYPE_QOS_DATA;
 987         hdr->frame_control = cpu_to_le16(fc);
 988
 989         return RX_CONTINUE;
 990 }
 991
 992 static int
 993 ieee80211_802_1x_port_control(struct ieee80211_txrx_data *rx)
 994 {
 995         if (unlikely(!rx->sta || !(rx->sta->flags & WLAN_STA_AUTHORIZED))) {
 996 #ifdef CONFIG_MAC80211_DEBUG
 997                 if (net_ratelimit())
 998                         printk(KERN_DEBUG "%s: dropped frame "
 999                                "(unauthorized port)\n", rx->dev->name);
1000 #endif /* CONFIG_MAC80211_DEBUG */
1001                 return -EACCES;
1002         }
1003
1004         return 0;
1005 }
1006
1007 static int
1008 ieee80211_drop_unencrypted(struct ieee80211_txrx_data *rx)
1009 {
1010         /*
1011          * Pass through unencrypted frames if the hardware has
1012          * decrypted them already.
1013          */
1014         if (rx->u.rx.status->flag & RX_FLAG_DECRYPTED)
1015                 return 0;
1016
1017         /* Drop unencrypted frames if key is set. */
1018         if (unlikely(!(rx->fc & IEEE80211_FCTL_PROTECTED) &&
1019                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
1020                      (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
1021                      (rx->key || rx->sdata->drop_unencrypted))) {
1022                 if (net_ratelimit())
1023                         printk(KERN_DEBUG "%s: RX non-WEP frame, but expected "
1024                                "encryption\n", rx->dev->name);
1025                 return -EACCES;
1026         }
1027         return 0;
1028 }
1029
1030 static int
1031 ieee80211_data_to_8023(struct ieee80211_txrx_data *rx)
1032 {
1033         struct net_device *dev = rx->dev;
1034         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
1035         u16 fc, hdrlen, ethertype;
1036         u8 *payload;
1037         u8 dst[ETH_ALEN];
1038         u8 src[ETH_ALEN];
1039         struct sk_buff *skb = rx->skb;
1040         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1041         DECLARE_MAC_BUF(mac);
1042         DECLARE_MAC_BUF(mac2);
1043         DECLARE_MAC_BUF(mac3);
1044         DECLARE_MAC_BUF(mac4);
1045
1046         fc = rx->fc;
1047
1048         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1049                 return -1;
1050
1051         hdrlen = ieee80211_get_hdrlen(fc);
1052
1053         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
1054          * header
1055          * IEEE 802.11 address fields:
1056          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
1057          *   0     0   DA    SA    BSSID n/a
1058          *   0     1   DA    BSSID SA    n/a
1059          *   1     0   BSSID SA    DA    n/a
1060          *   1     1   RA    TA    DA    SA
1061          */
1062
1063         switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
1064         case IEEE80211_FCTL_TODS:
1065                 /* BSSID SA DA */
1066                 memcpy(dst, hdr->addr3, ETH_ALEN);
1067                 memcpy(src, hdr->addr2, ETH_ALEN);
1068
1069                 if (unlikely(sdata->vif.type != IEEE80211_IF_TYPE_AP &&
1070                              sdata->vif.type != IEEE80211_IF_TYPE_VLAN)) {
1071                         if (net_ratelimit())
1072                                 printk(KERN_DEBUG "%s: dropped ToDS frame "
1073                                        "(BSSID=%s SA=%s DA=%s)\n",
1074                                        dev->name,
1075                                        print_mac(mac, hdr->addr1),
1076                                        print_mac(mac2, hdr->addr2),
1077                                        print_mac(mac3, hdr->addr3));
1078                         return -1;
1079                 }
1080                 break;
1081         case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
1082                 /* RA TA DA SA */
1083                 memcpy(dst, hdr->addr3, ETH_ALEN);
1084                 memcpy(src, hdr->addr4, ETH_ALEN);
1085
1086                 if (unlikely(sdata->vif.type != IEEE80211_IF_TYPE_WDS)) {
1087                         if (net_ratelimit())
1088                                 printk(KERN_DEBUG "%s: dropped FromDS&ToDS "
1089                                        "frame (RA=%s TA=%s DA=%s SA=%s)\n",
1090                                        rx->dev->name,
1091                                        print_mac(mac, hdr->addr1),
1092                                        print_mac(mac2, hdr->addr2),
1093                                        print_mac(mac3, hdr->addr3),
1094                                        print_mac(mac4, hdr->addr4));
1095                         return -1;
1096                 }
1097                 break;
1098         case IEEE80211_FCTL_FROMDS:
1099                 /* DA BSSID SA */
1100                 memcpy(dst, hdr->addr1, ETH_ALEN);
1101                 memcpy(src, hdr->addr3, ETH_ALEN);
1102
1103                 if (sdata->vif.type != IEEE80211_IF_TYPE_STA ||
1104                     (is_multicast_ether_addr(dst) &&
1105                      !compare_ether_addr(src, dev->dev_addr)))
1106                         return -1;
1107                 break;
1108         case 0:
1109                 /* DA SA BSSID */
1110                 memcpy(dst, hdr->addr1, ETH_ALEN);
1111                 memcpy(src, hdr->addr2, ETH_ALEN);
1112
1113                 if (sdata->vif.type != IEEE80211_IF_TYPE_IBSS) {
1114                         if (net_ratelimit()) {
1115                                 printk(KERN_DEBUG "%s: dropped IBSS frame "
1116                                        "(DA=%s SA=%s BSSID=%s)\n",
1117                                        dev->name,
1118                                        print_mac(mac, hdr->addr1),
1119                                        print_mac(mac2, hdr->addr2),
1120                                        print_mac(mac3, hdr->addr3));
1121                         }
1122                         return -1;
1123                 }
1124                 break;
1125         }
1126
1127         if (unlikely(skb->len - hdrlen < 8)) {
1128                 if (net_ratelimit()) {
1129                         printk(KERN_DEBUG "%s: RX too short data frame "
1130                                "payload\n", dev->name);
1131                 }
1132                 return -1;
1133         }
1134
1135         payload = skb->data + hdrlen;
1136         ethertype = (payload[6] << 8) | payload[7];
1137
1138         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1139                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1140                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1141                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1142                  * replace EtherType */
1143                 skb_pull(skb, hdrlen + 6);
1144                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1145                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1146         } else {
1147                 struct ethhdr *ehdr;
1148                 __be16 len;
1149
1150                 skb_pull(skb, hdrlen);
1151                 len = htons(skb->len);
1152                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1153                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1154                 memcpy(ehdr->h_source, src, ETH_ALEN);
1155                 ehdr->h_proto = len;
1156         }
1157         return 0;
1158 }
1159
1160 /*
1161  * requires that rx->skb is a frame with ethernet header
1162  */
1163 static bool ieee80211_frame_allowed(struct ieee80211_txrx_data *rx)
1164 {
1165         static const u8 pae_group_addr[ETH_ALEN]
1166                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1167         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1168
1169         /*
1170          * Allow EAPOL frames to us/the PAE group address regardless
1171          * of whether the frame was encrypted or not.
1172          */
1173         if (ehdr->h_proto == htons(ETH_P_PAE) &&
1174             (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
1175              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1176                 return true;
1177
1178         if (ieee80211_802_1x_port_control(rx) ||
1179             ieee80211_drop_unencrypted(rx))
1180                 return false;
1181
1182         return true;
1183 }
1184
1185 /*
1186  * requires that rx->skb is a frame with ethernet header
1187  */
1188 static void
1189 ieee80211_deliver_skb(struct ieee80211_txrx_data *rx)
1190 {
1191         struct net_device *dev = rx->dev;
1192         struct ieee80211_local *local = rx->local;
1193         struct sk_buff *skb, *xmit_skb;
1194         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1195         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1196         struct sta_info *dsta;
1197
1198         skb = rx->skb;
1199         xmit_skb = NULL;
1200
1201         if (local->bridge_packets && (sdata->vif.type == IEEE80211_IF_TYPE_AP ||
1202                                       sdata->vif.type == IEEE80211_IF_TYPE_VLAN) &&
1203             (rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
1204                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1205                         /*
1206                          * send multicast frames both to higher layers in
1207                          * local net stack and back to the wireless medium
1208                          */
1209                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1210                         if (!xmit_skb && net_ratelimit())
1211                                 printk(KERN_DEBUG "%s: failed to clone "
1212                                        "multicast frame\n", dev->name);
1213                 } else {
1214                         dsta = sta_info_get(local, skb->data);
1215                         if (dsta && dsta->dev == dev) {
1216                                 /*
1217                                  * The destination station is associated to
1218                                  * this AP (in this VLAN), so send the frame
1219                                  * directly to it and do not pass it to local
1220                                  * net stack.
1221                                  */
1222                                 xmit_skb = skb;
1223                                 skb = NULL;
1224                         }
1225                         if (dsta)
1226                                 sta_info_put(dsta);
1227                 }
1228         }
1229
1230         if (skb) {
1231                 /* deliver to local stack */
1232                 skb->protocol = eth_type_trans(skb, dev);
1233                 memset(skb->cb, 0, sizeof(skb->cb));
1234                 netif_rx(skb);
1235         }
1236
1237         if (xmit_skb) {
1238                 /* send to wireless media */
1239                 xmit_skb->protocol = htons(ETH_P_802_3);
1240                 skb_reset_network_header(xmit_skb);
1241                 skb_reset_mac_header(xmit_skb);
1242                 dev_queue_xmit(xmit_skb);
1243         }
1244 }
1245
1246 static ieee80211_rx_result
1247 ieee80211_rx_h_amsdu(struct ieee80211_txrx_data *rx)
1248 {
1249         struct net_device *dev = rx->dev;
1250         struct ieee80211_local *local = rx->local;
1251         u16 fc, ethertype;
1252         u8 *payload;
1253         struct sk_buff *skb = rx->skb, *frame = NULL;
1254         const struct ethhdr *eth;
1255         int remaining, err;
1256         u8 dst[ETH_ALEN];
1257         u8 src[ETH_ALEN];
1258         DECLARE_MAC_BUF(mac);
1259
1260         fc = rx->fc;
1261         if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
1262                 return RX_CONTINUE;
1263
1264         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1265                 return RX_DROP_MONITOR;
1266
1267         if (!(rx->flags & IEEE80211_TXRXD_RX_AMSDU))
1268                 return RX_CONTINUE;
1269
1270         err = ieee80211_data_to_8023(rx);
1271         if (unlikely(err))
1272                 return RX_DROP_UNUSABLE;
1273
1274         skb->dev = dev;
1275
1276         dev->stats.rx_packets++;
1277         dev->stats.rx_bytes += skb->len;
1278
1279         /* skip the wrapping header */
1280         eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
1281         if (!eth)
1282                 return RX_DROP_UNUSABLE;
1283
1284         while (skb != frame) {
1285                 u8 padding;
1286                 __be16 len = eth->h_proto;
1287                 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
1288
1289                 remaining = skb->len;
1290                 memcpy(dst, eth->h_dest, ETH_ALEN);
1291                 memcpy(src, eth->h_source, ETH_ALEN);
1292
1293                 padding = ((4 - subframe_len) & 0x3);
1294                 /* the last MSDU has no padding */
1295                 if (subframe_len > remaining) {
1296                         printk(KERN_DEBUG "%s: wrong buffer size", dev->name);
1297                         return RX_DROP_UNUSABLE;
1298                 }
1299
1300                 skb_pull(skb, sizeof(struct ethhdr));
1301                 /* if last subframe reuse skb */
1302                 if (remaining <= subframe_len + padding)
1303                         frame = skb;
1304                 else {
1305                         frame = dev_alloc_skb(local->hw.extra_tx_headroom +
1306                                               subframe_len);
1307
1308                         if (frame == NULL)
1309                                 return RX_DROP_UNUSABLE;
1310
1311                         skb_reserve(frame, local->hw.extra_tx_headroom +
1312                                     sizeof(struct ethhdr));
1313                         memcpy(skb_put(frame, ntohs(len)), skb->data,
1314                                 ntohs(len));
1315
1316                         eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
1317                                                         padding);
1318                         if (!eth) {
1319                                 printk(KERN_DEBUG "%s: wrong buffer size ",
1320                                        dev->name);
1321                                 dev_kfree_skb(frame);
1322                                 return RX_DROP_UNUSABLE;
1323                         }
1324                 }
1325
1326                 skb_reset_network_header(frame);
1327                 frame->dev = dev;
1328                 frame->priority = skb->priority;
1329                 rx->skb = frame;
1330
1331                 payload = frame->data;
1332                 ethertype = (payload[6] << 8) | payload[7];
1333
1334                 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1335                             ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1336                            compare_ether_addr(payload,
1337                                               bridge_tunnel_header) == 0)) {
1338                         /* remove RFC1042 or Bridge-Tunnel
1339                          * encapsulation and replace EtherType */
1340                         skb_pull(frame, 6);
1341                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1342                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1343                 } else {
1344                         memcpy(skb_push(frame, sizeof(__be16)),
1345                                &len, sizeof(__be16));
1346                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1347                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1348                 }
1349
1350                 if (!ieee80211_frame_allowed(rx)) {
1351                         if (skb == frame) /* last frame */
1352                                 return RX_DROP_UNUSABLE;
1353                         dev_kfree_skb(frame);
1354                         continue;
1355                 }
1356
1357                 ieee80211_deliver_skb(rx);
1358         }
1359
1360         return RX_QUEUED;
1361 }
1362
1363 static ieee80211_rx_result
1364 ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
1365 {
1366         struct net_device *dev = rx->dev;
1367         u16 fc;
1368         int err;
1369
1370         fc = rx->fc;
1371         if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
1372                 return RX_CONTINUE;
1373
1374         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1375                 return RX_DROP_MONITOR;
1376
1377         err = ieee80211_data_to_8023(rx);
1378         if (unlikely(err))
1379                 return RX_DROP_UNUSABLE;
1380
1381         if (!ieee80211_frame_allowed(rx))
1382                 return RX_DROP_MONITOR;
1383
1384         rx->skb->dev = dev;
1385
1386         dev->stats.rx_packets++;
1387         dev->stats.rx_bytes += rx->skb->len;
1388
1389         ieee80211_deliver_skb(rx);
1390
1391         return RX_QUEUED;
1392 }
1393
1394 static ieee80211_rx_result
1395 ieee80211_rx_h_ctrl(struct ieee80211_txrx_data *rx)
1396 {
1397         struct ieee80211_local *local = rx->local;
1398         struct ieee80211_hw *hw = &local->hw;
1399         struct sk_buff *skb = rx->skb;
1400         struct ieee80211_bar *bar = (struct ieee80211_bar *) skb->data;
1401         struct tid_ampdu_rx *tid_agg_rx;
1402         u16 start_seq_num;
1403         u16 tid;
1404
1405         if (likely((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL))
1406                 return RX_CONTINUE;
1407
1408         if ((rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_BACK_REQ) {
1409                 if (!rx->sta)
1410                         return RX_CONTINUE;
1411                 tid = le16_to_cpu(bar->control) >> 12;
1412                 tid_agg_rx = &(rx->sta->ampdu_mlme.tid_rx[tid]);
1413                 if (tid_agg_rx->state != HT_AGG_STATE_OPERATIONAL)
1414                         return RX_CONTINUE;
1415
1416                 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1417
1418                 /* reset session timer */
1419                 if (tid_agg_rx->timeout) {
1420                         unsigned long expires =
1421                                 jiffies + (tid_agg_rx->timeout / 1000) * HZ;
1422                         mod_timer(&tid_agg_rx->session_timer, expires);
1423                 }
1424
1425                 /* manage reordering buffer according to requested */
1426                 /* sequence number */
1427                 rcu_read_lock();
1428                 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL,
1429                                                  start_seq_num, 1);
1430                 rcu_read_unlock();
1431                 return RX_DROP_UNUSABLE;
1432         }
1433
1434         return RX_CONTINUE;
1435 }
1436
1437 static ieee80211_rx_result
1438 ieee80211_rx_h_mgmt(struct ieee80211_txrx_data *rx)
1439 {
1440         struct ieee80211_sub_if_data *sdata;
1441
1442         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
1443                 return RX_DROP_MONITOR;
1444
1445         sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1446         if ((sdata->vif.type == IEEE80211_IF_TYPE_STA ||
1447              sdata->vif.type == IEEE80211_IF_TYPE_IBSS) &&
1448             !(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME))
1449                 ieee80211_sta_rx_mgmt(rx->dev, rx->skb, rx->u.rx.status);
1450         else
1451                 return RX_DROP_MONITOR;
1452
1453         return RX_QUEUED;
1454 }
1455
1456 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1457                                             struct ieee80211_hdr *hdr,
1458                                             struct ieee80211_txrx_data *rx)
1459 {
1460         int keyidx, hdrlen;
1461         DECLARE_MAC_BUF(mac);
1462         DECLARE_MAC_BUF(mac2);
1463
1464         hdrlen = ieee80211_get_hdrlen_from_skb(rx->skb);
1465         if (rx->skb->len >= hdrlen + 4)
1466                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1467         else
1468                 keyidx = -1;
1469
1470         if (net_ratelimit())
1471                 printk(KERN_DEBUG "%s: TKIP hwaccel reported Michael MIC "
1472                        "failure from %s to %s keyidx=%d\n",
1473                        dev->name, print_mac(mac, hdr->addr2),
1474                        print_mac(mac2, hdr->addr1), keyidx);
1475
1476         if (!rx->sta) {
1477                 /*
1478                  * Some hardware seem to generate incorrect Michael MIC
1479                  * reports; ignore them to avoid triggering countermeasures.
1480                  */
1481                 if (net_ratelimit())
1482                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1483                                "error for unknown address %s\n",
1484                                dev->name, print_mac(mac, hdr->addr2));
1485                 goto ignore;
1486         }
1487
1488         if (!(rx->fc & IEEE80211_FCTL_PROTECTED)) {
1489                 if (net_ratelimit())
1490                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1491                                "error for a frame with no PROTECTED flag (src "
1492                                "%s)\n", dev->name, print_mac(mac, hdr->addr2));
1493                 goto ignore;
1494         }
1495
1496         if (rx->sdata->vif.type == IEEE80211_IF_TYPE_AP && keyidx) {
1497                 /*
1498                  * APs with pairwise keys should never receive Michael MIC
1499                  * errors for non-zero keyidx because these are reserved for
1500                  * group keys and only the AP is sending real multicast
1501                  * frames in the BSS.
1502                  */
1503                 if (net_ratelimit())
1504                         printk(KERN_DEBUG "%s: ignored Michael MIC error for "
1505                                "a frame with non-zero keyidx (%d)"
1506                                " (src %s)\n", dev->name, keyidx,
1507                                print_mac(mac, hdr->addr2));
1508                 goto ignore;
1509         }
1510
1511         if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
1512             ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
1513              (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)) {
1514                 if (net_ratelimit())
1515                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1516                                "error for a frame that cannot be encrypted "
1517                                "(fc=0x%04x) (src %s)\n",
1518                                dev->name, rx->fc, print_mac(mac, hdr->addr2));
1519                 goto ignore;
1520         }
1521
1522         mac80211_ev_michael_mic_failure(rx->dev, keyidx, hdr);
1523  ignore:
1524         dev_kfree_skb(rx->skb);
1525         rx->skb = NULL;
1526 }
1527
1528 static void ieee80211_rx_cooked_monitor(struct ieee80211_txrx_data *rx)
1529 {
1530         struct ieee80211_sub_if_data *sdata;
1531         struct ieee80211_local *local = rx->local;
1532         struct ieee80211_rtap_hdr {
1533                 struct ieee80211_radiotap_header hdr;
1534                 u8 flags;
1535                 u8 rate;
1536                 __le16 chan_freq;
1537                 __le16 chan_flags;
1538         } __attribute__ ((packed)) *rthdr;
1539         struct sk_buff *skb = rx->skb, *skb2;
1540         struct net_device *prev_dev = NULL;
1541         struct ieee80211_rx_status *status = rx->u.rx.status;
1542
1543         if (rx->flags & IEEE80211_TXRXD_RX_CMNTR_REPORTED)
1544                 goto out_free_skb;
1545
1546         if (skb_headroom(skb) < sizeof(*rthdr) &&
1547             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
1548                 goto out_free_skb;
1549
1550         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
1551         memset(rthdr, 0, sizeof(*rthdr));
1552         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
1553         rthdr->hdr.it_present =
1554                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
1555                             (1 << IEEE80211_RADIOTAP_RATE) |
1556                             (1 << IEEE80211_RADIOTAP_CHANNEL));
1557
1558         rthdr->rate = rx->u.rx.rate->bitrate / 5;
1559         rthdr->chan_freq = cpu_to_le16(status->freq);
1560
1561         if (status->band == IEEE80211_BAND_5GHZ)
1562                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
1563                                                 IEEE80211_CHAN_5GHZ);
1564         else
1565                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
1566                                                 IEEE80211_CHAN_2GHZ);
1567
1568         skb_set_mac_header(skb, 0);
1569         skb->ip_summed = CHECKSUM_UNNECESSARY;
1570         skb->pkt_type = PACKET_OTHERHOST;
1571         skb->protocol = htons(ETH_P_802_2);
1572
1573         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1574                 if (!netif_running(sdata->dev))
1575                         continue;
1576
1577                 if (sdata->vif.type != IEEE80211_IF_TYPE_MNTR ||
1578                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
1579                         continue;
1580
1581                 if (prev_dev) {
1582                         skb2 = skb_clone(skb, GFP_ATOMIC);
1583                         if (skb2) {
1584                                 skb2->dev = prev_dev;
1585                                 netif_rx(skb2);
1586                         }
1587                 }
1588
1589                 prev_dev = sdata->dev;
1590                 sdata->dev->stats.rx_packets++;
1591                 sdata->dev->stats.rx_bytes += skb->len;
1592         }
1593
1594         if (prev_dev) {
1595                 skb->dev = prev_dev;
1596                 netif_rx(skb);
1597                 skb = NULL;
1598         } else
1599                 goto out_free_skb;
1600
1601         rx->flags |= IEEE80211_TXRXD_RX_CMNTR_REPORTED;
1602         return;
1603
1604  out_free_skb:
1605         dev_kfree_skb(skb);
1606 }
1607
1608 typedef ieee80211_rx_result (*ieee80211_rx_handler)(struct ieee80211_txrx_data *);
1609 static ieee80211_rx_handler ieee80211_rx_handlers[] =
1610 {
1611         ieee80211_rx_h_if_stats,
1612         ieee80211_rx_h_passive_scan,
1613         ieee80211_rx_h_check,
1614         ieee80211_rx_h_decrypt,
1615         ieee80211_rx_h_sta_process,
1616         ieee80211_rx_h_defragment,
1617         ieee80211_rx_h_ps_poll,
1618         ieee80211_rx_h_michael_mic_verify,
1619         /* this must be after decryption - so header is counted in MPDU mic
1620          * must be before pae and data, so QOS_DATA format frames
1621          * are not passed to user space by these functions
1622          */
1623         ieee80211_rx_h_remove_qos_control,
1624         ieee80211_rx_h_amsdu,
1625         ieee80211_rx_h_data,
1626         ieee80211_rx_h_ctrl,
1627         ieee80211_rx_h_mgmt,
1628         NULL
1629 };
1630
1631 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
1632                                          struct ieee80211_txrx_data *rx,
1633                                          struct sk_buff *skb)
1634 {
1635         ieee80211_rx_handler *handler;
1636         ieee80211_rx_result res = RX_DROP_MONITOR;
1637
1638         rx->skb = skb;
1639         rx->sdata = sdata;
1640         rx->dev = sdata->dev;
1641
1642         for (handler = ieee80211_rx_handlers; *handler != NULL; handler++) {
1643                 res = (*handler)(rx);
1644
1645                 switch (res) {
1646                 case RX_CONTINUE:
1647                         continue;
1648                 case RX_DROP_UNUSABLE:
1649                 case RX_DROP_MONITOR:
1650                         I802_DEBUG_INC(sdata->local->rx_handlers_drop);
1651                         if (rx->sta)
1652                                 rx->sta->rx_dropped++;
1653                         break;
1654                 case RX_QUEUED:
1655                         I802_DEBUG_INC(sdata->local->rx_handlers_queued);
1656                         break;
1657                 }
1658                 break;
1659         }
1660
1661         switch (res) {
1662         case RX_CONTINUE:
1663         case RX_DROP_MONITOR:
1664                 ieee80211_rx_cooked_monitor(rx);
1665                 break;
1666         case RX_DROP_UNUSABLE:
1667                 dev_kfree_skb(rx->skb);
1668                 break;
1669         }
1670 }
1671
1672 /* main receive path */
1673
1674 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
1675                                 u8 *bssid, struct ieee80211_txrx_data *rx,
1676                                 struct ieee80211_hdr *hdr)
1677 {
1678         int multicast = is_multicast_ether_addr(hdr->addr1);
1679
1680         switch (sdata->vif.type) {
1681         case IEEE80211_IF_TYPE_STA:
1682                 if (!bssid)
1683                         return 0;
1684                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1685                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1686                                 return 0;
1687                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1688                 } else if (!multicast &&
1689                            compare_ether_addr(sdata->dev->dev_addr,
1690                                               hdr->addr1) != 0) {
1691                         if (!(sdata->dev->flags & IFF_PROMISC))
1692                                 return 0;
1693                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1694                 }
1695                 break;
1696         case IEEE80211_IF_TYPE_IBSS:
1697                 if (!bssid)
1698                         return 0;
1699                 if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT &&
1700                     (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_BEACON)
1701                         return 1;
1702                 else if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1703                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1704                                 return 0;
1705                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1706                 } else if (!multicast &&
1707                            compare_ether_addr(sdata->dev->dev_addr,
1708                                               hdr->addr1) != 0) {
1709                         if (!(sdata->dev->flags & IFF_PROMISC))
1710                                 return 0;
1711                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1712                 } else if (!rx->sta)
1713                         rx->sta = ieee80211_ibss_add_sta(sdata->dev, rx->skb,
1714                                                          bssid, hdr->addr2);
1715                 break;
1716         case IEEE80211_IF_TYPE_MESH_POINT:
1717                 if (!multicast &&
1718                     compare_ether_addr(sdata->dev->dev_addr,
1719                                        hdr->addr1) != 0) {
1720                         if (!(sdata->dev->flags & IFF_PROMISC))
1721                                 return 0;
1722
1723                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1724                 }
1725                 break;
1726         case IEEE80211_IF_TYPE_VLAN:
1727         case IEEE80211_IF_TYPE_AP:
1728                 if (!bssid) {
1729                         if (compare_ether_addr(sdata->dev->dev_addr,
1730                                                hdr->addr1))
1731                                 return 0;
1732                 } else if (!ieee80211_bssid_match(bssid,
1733                                         sdata->dev->dev_addr)) {
1734                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1735                                 return 0;
1736                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1737                 }
1738                 if (sdata->dev == sdata->local->mdev &&
1739                     !(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1740                         /* do not receive anything via
1741                          * master device when not scanning */
1742                         return 0;
1743                 break;
1744         case IEEE80211_IF_TYPE_WDS:
1745                 if (bssid ||
1746                     (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
1747                         return 0;
1748                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
1749                         return 0;
1750                 break;
1751         case IEEE80211_IF_TYPE_MNTR:
1752                 /* take everything */
1753                 break;
1754         case IEEE80211_IF_TYPE_INVALID:
1755                 /* should never get here */
1756                 WARN_ON(1);
1757                 break;
1758         }
1759
1760         return 1;
1761 }
1762
1763 /*
1764  * This is the actual Rx frames handler. as it blongs to Rx path it must
1765  * be called with rcu_read_lock protection.
1766  */
1767 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
1768                                          struct sk_buff *skb,
1769                                          struct ieee80211_rx_status *status,
1770                                          u32 load,
1771                                          struct ieee80211_rate *rate)
1772 {
1773         struct ieee80211_local *local = hw_to_local(hw);
1774         struct ieee80211_sub_if_data *sdata;
1775         struct ieee80211_hdr *hdr;
1776         struct ieee80211_txrx_data rx;
1777         u16 type;
1778         int prepares;
1779         struct ieee80211_sub_if_data *prev = NULL;
1780         struct sk_buff *skb_new;
1781         u8 *bssid;
1782
1783         hdr = (struct ieee80211_hdr *) skb->data;
1784         memset(&rx, 0, sizeof(rx));
1785         rx.skb = skb;
1786         rx.local = local;
1787
1788         rx.u.rx.status = status;
1789         rx.u.rx.load = load;
1790         rx.u.rx.rate = rate;
1791         rx.fc = le16_to_cpu(hdr->frame_control);
1792         type = rx.fc & IEEE80211_FCTL_FTYPE;
1793
1794         if (type == IEEE80211_FTYPE_DATA || type == IEEE80211_FTYPE_MGMT)
1795                 local->dot11ReceivedFragmentCount++;
1796
1797         rx.sta = sta_info_get(local, hdr->addr2);
1798         if (rx.sta) {
1799                 rx.dev = rx.sta->dev;
1800                 rx.sdata = IEEE80211_DEV_TO_SUB_IF(rx.dev);
1801         }
1802
1803         if ((status->flag & RX_FLAG_MMIC_ERROR)) {
1804                 ieee80211_rx_michael_mic_report(local->mdev, hdr, &rx);
1805                 goto end;
1806         }
1807
1808         if (unlikely(local->sta_sw_scanning || local->sta_hw_scanning))
1809                 rx.flags |= IEEE80211_TXRXD_RXIN_SCAN;
1810
1811         ieee80211_parse_qos(&rx);
1812         ieee80211_verify_ip_alignment(&rx);
1813
1814         skb = rx.skb;
1815
1816         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1817                 if (!netif_running(sdata->dev))
1818                         continue;
1819
1820                 if (sdata->vif.type == IEEE80211_IF_TYPE_MNTR)
1821                         continue;
1822
1823                 bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
1824                 rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
1825                 prepares = prepare_for_handlers(sdata, bssid, &rx, hdr);
1826
1827                 if (!prepares)
1828                         continue;
1829
1830                 /*
1831                  * frame is destined for this interface, but if it's not
1832                  * also for the previous one we handle that after the
1833                  * loop to avoid copying the SKB once too much
1834                  */
1835
1836                 if (!prev) {
1837                         prev = sdata;
1838                         continue;
1839                 }
1840
1841                 /*
1842                  * frame was destined for the previous interface
1843                  * so invoke RX handlers for it
1844                  */
1845
1846                 skb_new = skb_copy(skb, GFP_ATOMIC);
1847                 if (!skb_new) {
1848                         if (net_ratelimit())
1849                                 printk(KERN_DEBUG "%s: failed to copy "
1850                                        "multicast frame for %s",
1851                                        wiphy_name(local->hw.wiphy),
1852                                        prev->dev->name);
1853                         continue;
1854                 }
1855                 rx.fc = le16_to_cpu(hdr->frame_control);
1856                 ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
1857                 prev = sdata;
1858         }
1859         if (prev) {
1860                 rx.fc = le16_to_cpu(hdr->frame_control);
1861                 ieee80211_invoke_rx_handlers(prev, &rx, skb);
1862         } else
1863                 dev_kfree_skb(skb);
1864
1865  end:
1866         if (rx.sta)
1867                 sta_info_put(rx.sta);
1868 }
1869
1870 #define SEQ_MODULO 0x1000
1871 #define SEQ_MASK   0xfff
1872
1873 static inline int seq_less(u16 sq1, u16 sq2)
1874 {
1875         return (((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1));
1876 }
1877
1878 static inline u16 seq_inc(u16 sq)
1879 {
1880         return ((sq + 1) & SEQ_MASK);
1881 }
1882
1883 static inline u16 seq_sub(u16 sq1, u16 sq2)
1884 {
1885         return ((sq1 - sq2) & SEQ_MASK);
1886 }
1887
1888
1889 /*
1890  * As it function blongs to Rx path it must be called with
1891  * the proper rcu_read_lock protection for its flow.
1892  */
1893 u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
1894                                 struct tid_ampdu_rx *tid_agg_rx,
1895                                 struct sk_buff *skb, u16 mpdu_seq_num,
1896                                 int bar_req)
1897 {
1898         struct ieee80211_local *local = hw_to_local(hw);
1899         struct ieee80211_rx_status status;
1900         u16 head_seq_num, buf_size;
1901         int index;
1902         u32 pkt_load;
1903         struct ieee80211_supported_band *sband;
1904         struct ieee80211_rate *rate;
1905
1906         buf_size = tid_agg_rx->buf_size;
1907         head_seq_num = tid_agg_rx->head_seq_num;
1908
1909         /* frame with out of date sequence number */
1910         if (seq_less(mpdu_seq_num, head_seq_num)) {
1911                 dev_kfree_skb(skb);
1912                 return 1;
1913         }
1914
1915         /* if frame sequence number exceeds our buffering window size or
1916          * block Ack Request arrived - release stored frames */
1917         if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
1918                 /* new head to the ordering buffer */
1919                 if (bar_req)
1920                         head_seq_num = mpdu_seq_num;
1921                 else
1922                         head_seq_num =
1923                                 seq_inc(seq_sub(mpdu_seq_num, buf_size));
1924                 /* release stored frames up to new head to stack */
1925                 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
1926                         index = seq_sub(tid_agg_rx->head_seq_num,
1927                                 tid_agg_rx->ssn)
1928                                 % tid_agg_rx->buf_size;
1929
1930                         if (tid_agg_rx->reorder_buf[index]) {
1931                                 /* release the reordered frames to stack */
1932                                 memcpy(&status,
1933                                         tid_agg_rx->reorder_buf[index]->cb,
1934                                         sizeof(status));
1935                                 sband = local->hw.wiphy->bands[status.band];
1936                                 rate = &sband->bitrates[status.rate_idx];
1937                                 pkt_load = ieee80211_rx_load_stats(local,
1938                                                 tid_agg_rx->reorder_buf[index],
1939                                                 &status, rate);
1940                                 __ieee80211_rx_handle_packet(hw,
1941                                         tid_agg_rx->reorder_buf[index],
1942                                         &status, pkt_load, rate);
1943                                 tid_agg_rx->stored_mpdu_num--;
1944                                 tid_agg_rx->reorder_buf[index] = NULL;
1945                         }
1946                         tid_agg_rx->head_seq_num =
1947                                 seq_inc(tid_agg_rx->head_seq_num);
1948                 }
1949                 if (bar_req)
1950                         return 1;
1951         }
1952
1953         /* now the new frame is always in the range of the reordering */
1954         /* buffer window */
1955         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
1956                                 % tid_agg_rx->buf_size;
1957         /* check if we already stored this frame */
1958         if (tid_agg_rx->reorder_buf[index]) {
1959                 dev_kfree_skb(skb);
1960                 return 1;
1961         }
1962
1963         /* if arrived mpdu is in the right order and nothing else stored */
1964         /* release it immediately */
1965         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
1966                         tid_agg_rx->stored_mpdu_num == 0) {
1967                 tid_agg_rx->head_seq_num =
1968                         seq_inc(tid_agg_rx->head_seq_num);
1969                 return 0;
1970         }
1971
1972         /* put the frame in the reordering buffer */
1973         tid_agg_rx->reorder_buf[index] = skb;
1974         tid_agg_rx->stored_mpdu_num++;
1975         /* release the buffer until next missing frame */
1976         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
1977                                                 % tid_agg_rx->buf_size;
1978         while (tid_agg_rx->reorder_buf[index]) {
1979                 /* release the reordered frame back to stack */
1980                 memcpy(&status, tid_agg_rx->reorder_buf[index]->cb,
1981                         sizeof(status));
1982                 sband = local->hw.wiphy->bands[status.band];
1983                 rate = &sband->bitrates[status.rate_idx];
1984                 pkt_load = ieee80211_rx_load_stats(local,
1985                                         tid_agg_rx->reorder_buf[index],
1986                                         &status, rate);
1987                 __ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index],
1988                                              &status, pkt_load, rate);
1989                 tid_agg_rx->stored_mpdu_num--;
1990                 tid_agg_rx->reorder_buf[index] = NULL;
1991                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
1992                 index = seq_sub(tid_agg_rx->head_seq_num,
1993                         tid_agg_rx->ssn) % tid_agg_rx->buf_size;
1994         }
1995         return 1;
1996 }
1997
1998 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
1999                                      struct sk_buff *skb)
2000 {
2001         struct ieee80211_hw *hw = &local->hw;
2002         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
2003         struct sta_info *sta;
2004         struct tid_ampdu_rx *tid_agg_rx;
2005         u16 fc, sc;
2006         u16 mpdu_seq_num;
2007         u8 ret = 0, *qc;
2008         int tid;
2009
2010         sta = sta_info_get(local, hdr->addr2);
2011         if (!sta)
2012                 return ret;
2013
2014         fc = le16_to_cpu(hdr->frame_control);
2015
2016         /* filter the QoS data rx stream according to
2017          * STA/TID and check if this STA/TID is on aggregation */
2018         if (!WLAN_FC_IS_QOS_DATA(fc))
2019                 goto end_reorder;
2020
2021         qc = skb->data + ieee80211_get_hdrlen(fc) - QOS_CONTROL_LEN;
2022         tid = qc[0] & QOS_CONTROL_TID_MASK;
2023         tid_agg_rx = &(sta->ampdu_mlme.tid_rx[tid]);
2024
2025         if (tid_agg_rx->state != HT_AGG_STATE_OPERATIONAL)
2026                 goto end_reorder;
2027
2028         /* null data frames are excluded */
2029         if (unlikely(fc & IEEE80211_STYPE_NULLFUNC))
2030                 goto end_reorder;
2031
2032         /* new un-ordered ampdu frame - process it */
2033
2034         /* reset session timer */
2035         if (tid_agg_rx->timeout) {
2036                 unsigned long expires =
2037                         jiffies + (tid_agg_rx->timeout / 1000) * HZ;
2038                 mod_timer(&tid_agg_rx->session_timer, expires);
2039         }
2040
2041         /* if this mpdu is fragmented - terminate rx aggregation session */
2042         sc = le16_to_cpu(hdr->seq_ctrl);
2043         if (sc & IEEE80211_SCTL_FRAG) {
2044                 ieee80211_sta_stop_rx_ba_session(sta->dev, sta->addr,
2045                         tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
2046                 ret = 1;
2047                 goto end_reorder;
2048         }
2049
2050         /* according to mpdu sequence number deal with reordering buffer */
2051         mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
2052         ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb,
2053                                                 mpdu_seq_num, 0);
2054 end_reorder:
2055         if (sta)
2056                 sta_info_put(sta);
2057         return ret;
2058 }
2059
2060 /*
2061  * This is the receive path handler. It is called by a low level driver when an
2062  * 802.11 MPDU is received from the hardware.
2063  */
2064 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
2065                     struct ieee80211_rx_status *status)
2066 {
2067         struct ieee80211_local *local = hw_to_local(hw);
2068         u32 pkt_load;
2069         struct ieee80211_rate *rate = NULL;
2070         struct ieee80211_supported_band *sband;
2071
2072         if (status->band < 0 ||
2073             status->band > IEEE80211_NUM_BANDS) {
2074                 WARN_ON(1);
2075                 return;
2076         }
2077
2078         sband = local->hw.wiphy->bands[status->band];
2079
2080         if (!sband ||
2081             status->rate_idx < 0 ||
2082             status->rate_idx >= sband->n_bitrates) {
2083                 WARN_ON(1);
2084                 return;
2085         }
2086
2087         rate = &sband->bitrates[status->rate_idx];
2088
2089         /*
2090          * key references and virtual interfaces are protected using RCU
2091          * and this requires that we are in a read-side RCU section during
2092          * receive processing
2093          */
2094         rcu_read_lock();
2095
2096         /*
2097          * Frames with failed FCS/PLCP checksum are not returned,
2098          * all other frames are returned without radiotap header
2099          * if it was previously present.
2100          * Also, frames with less than 16 bytes are dropped.
2101          */
2102         skb = ieee80211_rx_monitor(local, skb, status, rate);
2103         if (!skb) {
2104                 rcu_read_unlock();
2105                 return;
2106         }
2107
2108         pkt_load = ieee80211_rx_load_stats(local, skb, status, rate);
2109         local->channel_use_raw += pkt_load;
2110
2111         if (!ieee80211_rx_reorder_ampdu(local, skb))
2112                 __ieee80211_rx_handle_packet(hw, skb, status, pkt_load, rate);
2113
2114         rcu_read_unlock();
2115 }
2116 EXPORT_SYMBOL(__ieee80211_rx);
2117
2118 /* This is a version of the rx handler that can be called from hard irq
2119  * context. Post the skb on the queue and schedule the tasklet */
2120 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
2121                           struct ieee80211_rx_status *status)
2122 {
2123         struct ieee80211_local *local = hw_to_local(hw);
2124
2125         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2126
2127         skb->dev = local->mdev;
2128         /* copy status into skb->cb for use by tasklet */
2129         memcpy(skb->cb, status, sizeof(*status));
2130         skb->pkt_type = IEEE80211_RX_MSG;
2131         skb_queue_tail(&local->skb_queue, skb);
2132         tasklet_schedule(&local->tasklet);
2133 }
2134 EXPORT_SYMBOL(ieee80211_rx_irqsafe);