SAFE public projects git trees. - safe/jmp/linux-2.6/blob - net/mac80211/rx.c

   1 /*
   2  * Copyright 2002-2005, Instant802 Networks, Inc.
   3  * Copyright 2005-2006, Devicescape Software, Inc.
   4  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   5  * Copyright 2007       Johannes Berg <johannes@sipsolutions.net>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/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         if (sdata->bss)
 600                 atomic_dec(&sdata->bss->num_sta_ps);
 601         sta->flags &= ~(WLAN_STA_PS | WLAN_STA_PSPOLL);
 602         if (!skb_queue_empty(&sta->ps_tx_buf)) {
 603                 if (sdata->bss)
 604                         bss_tim_clear(local, sdata->bss, sta->aid);
 605                 if (local->ops->set_tim)
 606                         local->ops->set_tim(local_to_hw(local), sta->aid, 0);
 607         }
 608 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 609         printk(KERN_DEBUG "%s: STA %s aid %d exits power save mode\n",
 610                dev->name, print_mac(mac, sta->addr), sta->aid);
 611 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 612         /* Send all buffered frames to the station */
 613         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
 614                 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 615                 sent++;
 616                 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
 617                 dev_queue_xmit(skb);
 618         }
 619         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
 620                 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 621                 local->total_ps_buffered--;
 622                 sent++;
 623 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 624                 printk(KERN_DEBUG "%s: STA %s aid %d send PS frame "
 625                        "since STA not sleeping anymore\n", dev->name,
 626                        print_mac(mac, sta->addr), sta->aid);
 627 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 628                 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
 629                 dev_queue_xmit(skb);
 630         }
 631
 632         return sent;
 633 }
 634
 635 static ieee80211_rx_result
 636 ieee80211_rx_h_sta_process(struct ieee80211_txrx_data *rx)
 637 {
 638         struct sta_info *sta = rx->sta;
 639         struct net_device *dev = rx->dev;
 640         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 641
 642         if (!sta)
 643                 return RX_CONTINUE;
 644
 645         /* Update last_rx only for IBSS packets which are for the current
 646          * BSSID to avoid keeping the current IBSS network alive in cases where
 647          * other STAs are using different BSSID. */
 648         if (rx->sdata->vif.type == IEEE80211_IF_TYPE_IBSS) {
 649                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
 650                                                 IEEE80211_IF_TYPE_IBSS);
 651                 if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0)
 652                         sta->last_rx = jiffies;
 653         } else
 654         if (!is_multicast_ether_addr(hdr->addr1) ||
 655             rx->sdata->vif.type == IEEE80211_IF_TYPE_STA) {
 656                 /* Update last_rx only for unicast frames in order to prevent
 657                  * the Probe Request frames (the only broadcast frames from a
 658                  * STA in infrastructure mode) from keeping a connection alive.
 659                  */
 660                 sta->last_rx = jiffies;
 661         }
 662
 663         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 664                 return RX_CONTINUE;
 665
 666         sta->rx_fragments++;
 667         sta->rx_bytes += rx->skb->len;
 668         sta->last_rssi = rx->u.rx.status->ssi;
 669         sta->last_signal = rx->u.rx.status->signal;
 670         sta->last_noise = rx->u.rx.status->noise;
 671
 672         if (!(rx->fc & IEEE80211_FCTL_MOREFRAGS)) {
 673                 /* Change STA power saving mode only in the end of a frame
 674                  * exchange sequence */
 675                 if ((sta->flags & WLAN_STA_PS) && !(rx->fc & IEEE80211_FCTL_PM))
 676                         rx->u.rx.sent_ps_buffered += ap_sta_ps_end(dev, sta);
 677                 else if (!(sta->flags & WLAN_STA_PS) &&
 678                          (rx->fc & IEEE80211_FCTL_PM))
 679                         ap_sta_ps_start(dev, sta);
 680         }
 681
 682         /* Drop data::nullfunc frames silently, since they are used only to
 683          * control station power saving mode. */
 684         if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 685             (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_NULLFUNC) {
 686                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
 687                 /* Update counter and free packet here to avoid counting this
 688                  * as a dropped packed. */
 689                 sta->rx_packets++;
 690                 dev_kfree_skb(rx->skb);
 691                 return RX_QUEUED;
 692         }
 693
 694         return RX_CONTINUE;
 695 } /* ieee80211_rx_h_sta_process */
 696
 697 static inline struct ieee80211_fragment_entry *
 698 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
 699                          unsigned int frag, unsigned int seq, int rx_queue,
 700                          struct sk_buff **skb)
 701 {
 702         struct ieee80211_fragment_entry *entry;
 703         int idx;
 704
 705         idx = sdata->fragment_next;
 706         entry = &sdata->fragments[sdata->fragment_next++];
 707         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
 708                 sdata->fragment_next = 0;
 709
 710         if (!skb_queue_empty(&entry->skb_list)) {
 711 #ifdef CONFIG_MAC80211_DEBUG
 712                 struct ieee80211_hdr *hdr =
 713                         (struct ieee80211_hdr *) entry->skb_list.next->data;
 714                 DECLARE_MAC_BUF(mac);
 715                 DECLARE_MAC_BUF(mac2);
 716                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
 717                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
 718                        "addr1=%s addr2=%s\n",
 719                        sdata->dev->name, idx,
 720                        jiffies - entry->first_frag_time, entry->seq,
 721                        entry->last_frag, print_mac(mac, hdr->addr1),
 722                        print_mac(mac2, hdr->addr2));
 723 #endif /* CONFIG_MAC80211_DEBUG */
 724                 __skb_queue_purge(&entry->skb_list);
 725         }
 726
 727         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
 728         *skb = NULL;
 729         entry->first_frag_time = jiffies;
 730         entry->seq = seq;
 731         entry->rx_queue = rx_queue;
 732         entry->last_frag = frag;
 733         entry->ccmp = 0;
 734         entry->extra_len = 0;
 735
 736         return entry;
 737 }
 738
 739 static inline struct ieee80211_fragment_entry *
 740 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
 741                           u16 fc, unsigned int frag, unsigned int seq,
 742                           int rx_queue, struct ieee80211_hdr *hdr)
 743 {
 744         struct ieee80211_fragment_entry *entry;
 745         int i, idx;
 746
 747         idx = sdata->fragment_next;
 748         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
 749                 struct ieee80211_hdr *f_hdr;
 750                 u16 f_fc;
 751
 752                 idx--;
 753                 if (idx < 0)
 754                         idx = IEEE80211_FRAGMENT_MAX - 1;
 755
 756                 entry = &sdata->fragments[idx];
 757                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
 758                     entry->rx_queue != rx_queue ||
 759                     entry->last_frag + 1 != frag)
 760                         continue;
 761
 762                 f_hdr = (struct ieee80211_hdr *) entry->skb_list.next->data;
 763                 f_fc = le16_to_cpu(f_hdr->frame_control);
 764
 765                 if ((fc & IEEE80211_FCTL_FTYPE) != (f_fc & IEEE80211_FCTL_FTYPE) ||
 766                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
 767                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
 768                         continue;
 769
 770                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
 771                         __skb_queue_purge(&entry->skb_list);
 772                         continue;
 773                 }
 774                 return entry;
 775         }
 776
 777         return NULL;
 778 }
 779
 780 static ieee80211_rx_result
 781 ieee80211_rx_h_defragment(struct ieee80211_txrx_data *rx)
 782 {
 783         struct ieee80211_hdr *hdr;
 784         u16 sc;
 785         unsigned int frag, seq;
 786         struct ieee80211_fragment_entry *entry;
 787         struct sk_buff *skb;
 788         DECLARE_MAC_BUF(mac);
 789
 790         hdr = (struct ieee80211_hdr *) rx->skb->data;
 791         sc = le16_to_cpu(hdr->seq_ctrl);
 792         frag = sc & IEEE80211_SCTL_FRAG;
 793
 794         if (likely((!(rx->fc & IEEE80211_FCTL_MOREFRAGS) && frag == 0) ||
 795                    (rx->skb)->len < 24 ||
 796                    is_multicast_ether_addr(hdr->addr1))) {
 797                 /* not fragmented */
 798                 goto out;
 799         }
 800         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
 801
 802         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
 803
 804         if (frag == 0) {
 805                 /* This is the first fragment of a new frame. */
 806                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
 807                                                  rx->u.rx.queue, &(rx->skb));
 808                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
 809                     (rx->fc & IEEE80211_FCTL_PROTECTED)) {
 810                         /* Store CCMP PN so that we can verify that the next
 811                          * fragment has a sequential PN value. */
 812                         entry->ccmp = 1;
 813                         memcpy(entry->last_pn,
 814                                rx->key->u.ccmp.rx_pn[rx->u.rx.queue],
 815                                CCMP_PN_LEN);
 816                 }
 817                 return RX_QUEUED;
 818         }
 819
 820         /* This is a fragment for a frame that should already be pending in
 821          * fragment cache. Add this fragment to the end of the pending entry.
 822          */
 823         entry = ieee80211_reassemble_find(rx->sdata, rx->fc, frag, seq,
 824                                           rx->u.rx.queue, hdr);
 825         if (!entry) {
 826                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 827                 return RX_DROP_MONITOR;
 828         }
 829
 830         /* Verify that MPDUs within one MSDU have sequential PN values.
 831          * (IEEE 802.11i, 8.3.3.4.5) */
 832         if (entry->ccmp) {
 833                 int i;
 834                 u8 pn[CCMP_PN_LEN], *rpn;
 835                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
 836                         return RX_DROP_UNUSABLE;
 837                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
 838                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
 839                         pn[i]++;
 840                         if (pn[i])
 841                                 break;
 842                 }
 843                 rpn = rx->key->u.ccmp.rx_pn[rx->u.rx.queue];
 844                 if (memcmp(pn, rpn, CCMP_PN_LEN) != 0) {
 845                         if (net_ratelimit())
 846                                 printk(KERN_DEBUG "%s: defrag: CCMP PN not "
 847                                        "sequential A2=%s"
 848                                        " PN=%02x%02x%02x%02x%02x%02x "
 849                                        "(expected %02x%02x%02x%02x%02x%02x)\n",
 850                                        rx->dev->name, print_mac(mac, hdr->addr2),
 851                                        rpn[0], rpn[1], rpn[2], rpn[3], rpn[4],
 852                                        rpn[5], pn[0], pn[1], pn[2], pn[3],
 853                                        pn[4], pn[5]);
 854                         return RX_DROP_UNUSABLE;
 855                 }
 856                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
 857         }
 858
 859         skb_pull(rx->skb, ieee80211_get_hdrlen(rx->fc));
 860         __skb_queue_tail(&entry->skb_list, rx->skb);
 861         entry->last_frag = frag;
 862         entry->extra_len += rx->skb->len;
 863         if (rx->fc & IEEE80211_FCTL_MOREFRAGS) {
 864                 rx->skb = NULL;
 865                 return RX_QUEUED;
 866         }
 867
 868         rx->skb = __skb_dequeue(&entry->skb_list);
 869         if (skb_tailroom(rx->skb) < entry->extra_len) {
 870                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
 871                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
 872                                               GFP_ATOMIC))) {
 873                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 874                         __skb_queue_purge(&entry->skb_list);
 875                         return RX_DROP_UNUSABLE;
 876                 }
 877         }
 878         while ((skb = __skb_dequeue(&entry->skb_list))) {
 879                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
 880                 dev_kfree_skb(skb);
 881         }
 882
 883         /* Complete frame has been reassembled - process it now */
 884         rx->flags |= IEEE80211_TXRXD_FRAGMENTED;
 885
 886  out:
 887         if (rx->sta)
 888                 rx->sta->rx_packets++;
 889         if (is_multicast_ether_addr(hdr->addr1))
 890                 rx->local->dot11MulticastReceivedFrameCount++;
 891         else
 892                 ieee80211_led_rx(rx->local);
 893         return RX_CONTINUE;
 894 }
 895
 896 static ieee80211_rx_result
 897 ieee80211_rx_h_ps_poll(struct ieee80211_txrx_data *rx)
 898 {
 899         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
 900         struct sk_buff *skb;
 901         int no_pending_pkts;
 902         DECLARE_MAC_BUF(mac);
 903
 904         if (likely(!rx->sta ||
 905                    (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL ||
 906                    (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PSPOLL ||
 907                    !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)))
 908                 return RX_CONTINUE;
 909
 910         if ((sdata->vif.type != IEEE80211_IF_TYPE_AP) &&
 911             (sdata->vif.type != IEEE80211_IF_TYPE_VLAN))
 912                 return RX_DROP_UNUSABLE;
 913
 914         skb = skb_dequeue(&rx->sta->tx_filtered);
 915         if (!skb) {
 916                 skb = skb_dequeue(&rx->sta->ps_tx_buf);
 917                 if (skb)
 918                         rx->local->total_ps_buffered--;
 919         }
 920         no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
 921                 skb_queue_empty(&rx->sta->ps_tx_buf);
 922
 923         if (skb) {
 924                 struct ieee80211_hdr *hdr =
 925                         (struct ieee80211_hdr *) skb->data;
 926
 927                 /*
 928                  * Tell TX path to send one frame even though the STA may
 929                  * still remain is PS mode after this frame exchange.
 930                  */
 931                 rx->sta->flags |= WLAN_STA_PSPOLL;
 932
 933 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 934                 printk(KERN_DEBUG "STA %s aid %d: PS Poll (entries after %d)\n",
 935                        print_mac(mac, rx->sta->addr), rx->sta->aid,
 936                        skb_queue_len(&rx->sta->ps_tx_buf));
 937 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 938
 939                 /* Use MoreData flag to indicate whether there are more
 940                  * buffered frames for this STA */
 941                 if (no_pending_pkts)
 942                         hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
 943                 else
 944                         hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
 945
 946                 dev_queue_xmit(skb);
 947
 948                 if (no_pending_pkts) {
 949                         if (rx->sdata->bss)
 950                                 bss_tim_clear(rx->local, rx->sdata->bss, rx->sta->aid);
 951                         if (rx->local->ops->set_tim)
 952                                 rx->local->ops->set_tim(local_to_hw(rx->local),
 953                                                        rx->sta->aid, 0);
 954                 }
 955 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 956         } else if (!rx->u.rx.sent_ps_buffered) {
 957                 printk(KERN_DEBUG "%s: STA %s sent PS Poll even "
 958                        "though there is no buffered frames for it\n",
 959                        rx->dev->name, print_mac(mac, rx->sta->addr));
 960 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 961
 962         }
 963
 964         /* Free PS Poll skb here instead of returning RX_DROP that would
 965          * count as an dropped frame. */
 966         dev_kfree_skb(rx->skb);
 967
 968         return RX_QUEUED;
 969 }
 970
 971 static ieee80211_rx_result
 972 ieee80211_rx_h_remove_qos_control(struct ieee80211_txrx_data *rx)
 973 {
 974         u16 fc = rx->fc;
 975         u8 *data = rx->skb->data;
 976         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) data;
 977
 978         if (!WLAN_FC_IS_QOS_DATA(fc))
 979                 return RX_CONTINUE;
 980
 981         /* remove the qos control field, update frame type and meta-data */
 982         memmove(data + 2, data, ieee80211_get_hdrlen(fc) - 2);
 983         hdr = (struct ieee80211_hdr *) skb_pull(rx->skb, 2);
 984         /* change frame type to non QOS */
 985         rx->fc = fc &= ~IEEE80211_STYPE_QOS_DATA;
 986         hdr->frame_control = cpu_to_le16(fc);
 987
 988         return RX_CONTINUE;
 989 }
 990
 991 static int
 992 ieee80211_802_1x_port_control(struct ieee80211_txrx_data *rx)
 993 {
 994         if (unlikely(!rx->sta || !(rx->sta->flags & WLAN_STA_AUTHORIZED))) {
 995 #ifdef CONFIG_MAC80211_DEBUG
 996                 if (net_ratelimit())
 997                         printk(KERN_DEBUG "%s: dropped frame "
 998                                "(unauthorized port)\n", rx->dev->name);
 999 #endif /* CONFIG_MAC80211_DEBUG */
1000                 return -EACCES;
1001         }
1002
1003         return 0;
1004 }
1005
1006 static int
1007 ieee80211_drop_unencrypted(struct ieee80211_txrx_data *rx)
1008 {
1009         /*
1010          * Pass through unencrypted frames if the hardware has
1011          * decrypted them already.
1012          */
1013         if (rx->u.rx.status->flag & RX_FLAG_DECRYPTED)
1014                 return 0;
1015
1016         /* Drop unencrypted frames if key is set. */
1017         if (unlikely(!(rx->fc & IEEE80211_FCTL_PROTECTED) &&
1018                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
1019                      (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
1020                      (rx->key || rx->sdata->drop_unencrypted))) {
1021                 if (net_ratelimit())
1022                         printk(KERN_DEBUG "%s: RX non-WEP frame, but expected "
1023                                "encryption\n", rx->dev->name);
1024                 return -EACCES;
1025         }
1026         return 0;
1027 }
1028
1029 static int
1030 ieee80211_data_to_8023(struct ieee80211_txrx_data *rx)
1031 {
1032         struct net_device *dev = rx->dev;
1033         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
1034         u16 fc, hdrlen, ethertype;
1035         u8 *payload;
1036         u8 dst[ETH_ALEN];
1037         u8 src[ETH_ALEN];
1038         struct sk_buff *skb = rx->skb;
1039         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1040         DECLARE_MAC_BUF(mac);
1041         DECLARE_MAC_BUF(mac2);
1042         DECLARE_MAC_BUF(mac3);
1043         DECLARE_MAC_BUF(mac4);
1044
1045         fc = rx->fc;
1046
1047         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1048                 return -1;
1049
1050         hdrlen = ieee80211_get_hdrlen(fc);
1051
1052         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
1053          * header
1054          * IEEE 802.11 address fields:
1055          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
1056          *   0     0   DA    SA    BSSID n/a
1057          *   0     1   DA    BSSID SA    n/a
1058          *   1     0   BSSID SA    DA    n/a
1059          *   1     1   RA    TA    DA    SA
1060          */
1061
1062         switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
1063         case IEEE80211_FCTL_TODS:
1064                 /* BSSID SA DA */
1065                 memcpy(dst, hdr->addr3, ETH_ALEN);
1066                 memcpy(src, hdr->addr2, ETH_ALEN);
1067
1068                 if (unlikely(sdata->vif.type != IEEE80211_IF_TYPE_AP &&
1069                              sdata->vif.type != IEEE80211_IF_TYPE_VLAN)) {
1070                         if (net_ratelimit())
1071                                 printk(KERN_DEBUG "%s: dropped ToDS frame "
1072                                        "(BSSID=%s SA=%s DA=%s)\n",
1073                                        dev->name,
1074                                        print_mac(mac, hdr->addr1),
1075                                        print_mac(mac2, hdr->addr2),
1076                                        print_mac(mac3, hdr->addr3));
1077                         return -1;
1078                 }
1079                 break;
1080         case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
1081                 /* RA TA DA SA */
1082                 memcpy(dst, hdr->addr3, ETH_ALEN);
1083                 memcpy(src, hdr->addr4, ETH_ALEN);
1084
1085                 if (unlikely(sdata->vif.type != IEEE80211_IF_TYPE_WDS)) {
1086                         if (net_ratelimit())
1087                                 printk(KERN_DEBUG "%s: dropped FromDS&ToDS "
1088                                        "frame (RA=%s TA=%s DA=%s SA=%s)\n",
1089                                        rx->dev->name,
1090                                        print_mac(mac, hdr->addr1),
1091                                        print_mac(mac2, hdr->addr2),
1092                                        print_mac(mac3, hdr->addr3),
1093                                        print_mac(mac4, hdr->addr4));
1094                         return -1;
1095                 }
1096                 break;
1097         case IEEE80211_FCTL_FROMDS:
1098                 /* DA BSSID SA */
1099                 memcpy(dst, hdr->addr1, ETH_ALEN);
1100                 memcpy(src, hdr->addr3, ETH_ALEN);
1101
1102                 if (sdata->vif.type != IEEE80211_IF_TYPE_STA ||
1103                     (is_multicast_ether_addr(dst) &&
1104                      !compare_ether_addr(src, dev->dev_addr)))
1105                         return -1;
1106                 break;
1107         case 0:
1108                 /* DA SA BSSID */
1109                 memcpy(dst, hdr->addr1, ETH_ALEN);
1110                 memcpy(src, hdr->addr2, ETH_ALEN);
1111
1112                 if (sdata->vif.type != IEEE80211_IF_TYPE_IBSS) {
1113                         if (net_ratelimit()) {
1114                                 printk(KERN_DEBUG "%s: dropped IBSS frame "
1115                                        "(DA=%s SA=%s BSSID=%s)\n",
1116                                        dev->name,
1117                                        print_mac(mac, hdr->addr1),
1118                                        print_mac(mac2, hdr->addr2),
1119                                        print_mac(mac3, hdr->addr3));
1120                         }
1121                         return -1;
1122                 }
1123                 break;
1124         }
1125
1126         if (unlikely(skb->len - hdrlen < 8)) {
1127                 if (net_ratelimit()) {
1128                         printk(KERN_DEBUG "%s: RX too short data frame "
1129                                "payload\n", dev->name);
1130                 }
1131                 return -1;
1132         }
1133
1134         payload = skb->data + hdrlen;
1135         ethertype = (payload[6] << 8) | payload[7];
1136
1137         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1138                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1139                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1140                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1141                  * replace EtherType */
1142                 skb_pull(skb, hdrlen + 6);
1143                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1144                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1145         } else {
1146                 struct ethhdr *ehdr;
1147                 __be16 len;
1148
1149                 skb_pull(skb, hdrlen);
1150                 len = htons(skb->len);
1151                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1152                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1153                 memcpy(ehdr->h_source, src, ETH_ALEN);
1154                 ehdr->h_proto = len;
1155         }
1156         return 0;
1157 }
1158
1159 /*
1160  * requires that rx->skb is a frame with ethernet header
1161  */
1162 static bool ieee80211_frame_allowed(struct ieee80211_txrx_data *rx)
1163 {
1164         static const u8 pae_group_addr[ETH_ALEN]
1165                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1166         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1167
1168         /*
1169          * Allow EAPOL frames to us/the PAE group address regardless
1170          * of whether the frame was encrypted or not.
1171          */
1172         if (ehdr->h_proto == htons(ETH_P_PAE) &&
1173             (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
1174              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1175                 return true;
1176
1177         if (ieee80211_802_1x_port_control(rx) ||
1178             ieee80211_drop_unencrypted(rx))
1179                 return false;
1180
1181         return true;
1182 }
1183
1184 /*
1185  * requires that rx->skb is a frame with ethernet header
1186  */
1187 static void
1188 ieee80211_deliver_skb(struct ieee80211_txrx_data *rx)
1189 {
1190         struct net_device *dev = rx->dev;
1191         struct ieee80211_local *local = rx->local;
1192         struct sk_buff *skb, *xmit_skb;
1193         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1194         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1195         struct sta_info *dsta;
1196
1197         skb = rx->skb;
1198         xmit_skb = NULL;
1199
1200         if (local->bridge_packets && (sdata->vif.type == IEEE80211_IF_TYPE_AP ||
1201                                       sdata->vif.type == IEEE80211_IF_TYPE_VLAN) &&
1202             (rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
1203                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1204                         /*
1205                          * send multicast frames both to higher layers in
1206                          * local net stack and back to the wireless medium
1207                          */
1208                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1209                         if (!xmit_skb && net_ratelimit())
1210                                 printk(KERN_DEBUG "%s: failed to clone "
1211                                        "multicast frame\n", dev->name);
1212                 } else {
1213                         dsta = sta_info_get(local, skb->data);
1214                         if (dsta && dsta->dev == dev) {
1215                                 /*
1216                                  * The destination station is associated to
1217                                  * this AP (in this VLAN), so send the frame
1218                                  * directly to it and do not pass it to local
1219                                  * net stack.
1220                                  */
1221                                 xmit_skb = skb;
1222                                 skb = NULL;
1223                         }
1224                         if (dsta)
1225                                 sta_info_put(dsta);
1226                 }
1227         }
1228
1229         if (skb) {
1230                 /* deliver to local stack */
1231                 skb->protocol = eth_type_trans(skb, dev);
1232                 memset(skb->cb, 0, sizeof(skb->cb));
1233                 netif_rx(skb);
1234         }
1235
1236         if (xmit_skb) {
1237                 /* send to wireless media */
1238                 xmit_skb->protocol = htons(ETH_P_802_3);
1239                 skb_reset_network_header(xmit_skb);
1240                 skb_reset_mac_header(xmit_skb);
1241                 dev_queue_xmit(xmit_skb);
1242         }
1243 }
1244
1245 static ieee80211_rx_result
1246 ieee80211_rx_h_amsdu(struct ieee80211_txrx_data *rx)
1247 {
1248         struct net_device *dev = rx->dev;
1249         struct ieee80211_local *local = rx->local;
1250         u16 fc, ethertype;
1251         u8 *payload;
1252         struct sk_buff *skb = rx->skb, *frame = NULL;
1253         const struct ethhdr *eth;
1254         int remaining, err;
1255         u8 dst[ETH_ALEN];
1256         u8 src[ETH_ALEN];
1257         DECLARE_MAC_BUF(mac);
1258
1259         fc = rx->fc;
1260         if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
1261                 return RX_CONTINUE;
1262
1263         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1264                 return RX_DROP_MONITOR;
1265
1266         if (!(rx->flags & IEEE80211_TXRXD_RX_AMSDU))
1267                 return RX_CONTINUE;
1268
1269         err = ieee80211_data_to_8023(rx);
1270         if (unlikely(err))
1271                 return RX_DROP_UNUSABLE;
1272
1273         skb->dev = dev;
1274
1275         dev->stats.rx_packets++;
1276         dev->stats.rx_bytes += skb->len;
1277
1278         /* skip the wrapping header */
1279         eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
1280         if (!eth)
1281                 return RX_DROP_UNUSABLE;
1282
1283         while (skb != frame) {
1284                 u8 padding;
1285                 __be16 len = eth->h_proto;
1286                 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
1287
1288                 remaining = skb->len;
1289                 memcpy(dst, eth->h_dest, ETH_ALEN);
1290                 memcpy(src, eth->h_source, ETH_ALEN);
1291
1292                 padding = ((4 - subframe_len) & 0x3);
1293                 /* the last MSDU has no padding */
1294                 if (subframe_len > remaining) {
1295                         printk(KERN_DEBUG "%s: wrong buffer size", dev->name);
1296                         return RX_DROP_UNUSABLE;
1297                 }
1298
1299                 skb_pull(skb, sizeof(struct ethhdr));
1300                 /* if last subframe reuse skb */
1301                 if (remaining <= subframe_len + padding)
1302                         frame = skb;
1303                 else {
1304                         frame = dev_alloc_skb(local->hw.extra_tx_headroom +
1305                                               subframe_len);
1306
1307                         if (frame == NULL)
1308                                 return RX_DROP_UNUSABLE;
1309
1310                         skb_reserve(frame, local->hw.extra_tx_headroom +
1311                                     sizeof(struct ethhdr));
1312                         memcpy(skb_put(frame, ntohs(len)), skb->data,
1313                                 ntohs(len));
1314
1315                         eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
1316                                                         padding);
1317                         if (!eth) {
1318                                 printk(KERN_DEBUG "%s: wrong buffer size ",
1319                                        dev->name);
1320                                 dev_kfree_skb(frame);
1321                                 return RX_DROP_UNUSABLE;
1322                         }
1323                 }
1324
1325                 skb_reset_network_header(frame);
1326                 frame->dev = dev;
1327                 frame->priority = skb->priority;
1328                 rx->skb = frame;
1329
1330                 payload = frame->data;
1331                 ethertype = (payload[6] << 8) | payload[7];
1332
1333                 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1334                             ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1335                            compare_ether_addr(payload,
1336                                               bridge_tunnel_header) == 0)) {
1337                         /* remove RFC1042 or Bridge-Tunnel
1338                          * encapsulation and replace EtherType */
1339                         skb_pull(frame, 6);
1340                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1341                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1342                 } else {
1343                         memcpy(skb_push(frame, sizeof(__be16)),
1344                                &len, sizeof(__be16));
1345                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1346                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1347                 }
1348
1349                 if (!ieee80211_frame_allowed(rx)) {
1350                         if (skb == frame) /* last frame */
1351                                 return RX_DROP_UNUSABLE;
1352                         dev_kfree_skb(frame);
1353                         continue;
1354                 }
1355
1356                 ieee80211_deliver_skb(rx);
1357         }
1358
1359         return RX_QUEUED;
1360 }
1361
1362 static ieee80211_rx_result
1363 ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
1364 {
1365         struct net_device *dev = rx->dev;
1366         u16 fc;
1367         int err;
1368
1369         fc = rx->fc;
1370         if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
1371                 return RX_CONTINUE;
1372
1373         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1374                 return RX_DROP_MONITOR;
1375
1376         err = ieee80211_data_to_8023(rx);
1377         if (unlikely(err))
1378                 return RX_DROP_UNUSABLE;
1379
1380         if (!ieee80211_frame_allowed(rx))
1381                 return RX_DROP_MONITOR;
1382
1383         rx->skb->dev = dev;
1384
1385         dev->stats.rx_packets++;
1386         dev->stats.rx_bytes += rx->skb->len;
1387
1388         ieee80211_deliver_skb(rx);
1389
1390         return RX_QUEUED;
1391 }
1392
1393 static ieee80211_rx_result
1394 ieee80211_rx_h_ctrl(struct ieee80211_txrx_data *rx)
1395 {
1396         struct ieee80211_local *local = rx->local;
1397         struct ieee80211_hw *hw = &local->hw;
1398         struct sk_buff *skb = rx->skb;
1399         struct ieee80211_bar *bar = (struct ieee80211_bar *) skb->data;
1400         struct tid_ampdu_rx *tid_agg_rx;
1401         u16 start_seq_num;
1402         u16 tid;
1403
1404         if (likely((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL))
1405                 return RX_CONTINUE;
1406
1407         if ((rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_BACK_REQ) {
1408                 if (!rx->sta)
1409                         return RX_CONTINUE;
1410                 tid = le16_to_cpu(bar->control) >> 12;
1411                 tid_agg_rx = &(rx->sta->ampdu_mlme.tid_rx[tid]);
1412                 if (tid_agg_rx->state != HT_AGG_STATE_OPERATIONAL)
1413                         return RX_CONTINUE;
1414
1415                 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1416
1417                 /* reset session timer */
1418                 if (tid_agg_rx->timeout) {
1419                         unsigned long expires =
1420                                 jiffies + (tid_agg_rx->timeout / 1000) * HZ;
1421                         mod_timer(&tid_agg_rx->session_timer, expires);
1422                 }
1423
1424                 /* manage reordering buffer according to requested */
1425                 /* sequence number */
1426                 rcu_read_lock();
1427                 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL,
1428                                                  start_seq_num, 1);
1429                 rcu_read_unlock();
1430                 return RX_DROP_UNUSABLE;
1431         }
1432
1433         return RX_CONTINUE;
1434 }
1435
1436 static ieee80211_rx_result
1437 ieee80211_rx_h_mgmt(struct ieee80211_txrx_data *rx)
1438 {
1439         struct ieee80211_sub_if_data *sdata;
1440
1441         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
1442                 return RX_DROP_MONITOR;
1443
1444         sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1445         if ((sdata->vif.type == IEEE80211_IF_TYPE_STA ||
1446              sdata->vif.type == IEEE80211_IF_TYPE_IBSS) &&
1447             !(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME))
1448                 ieee80211_sta_rx_mgmt(rx->dev, rx->skb, rx->u.rx.status);
1449         else
1450                 return RX_DROP_MONITOR;
1451
1452         return RX_QUEUED;
1453 }
1454
1455 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1456                                             struct ieee80211_hdr *hdr,
1457                                             struct ieee80211_txrx_data *rx)
1458 {
1459         int keyidx, hdrlen;
1460         DECLARE_MAC_BUF(mac);
1461         DECLARE_MAC_BUF(mac2);
1462
1463         hdrlen = ieee80211_get_hdrlen_from_skb(rx->skb);
1464         if (rx->skb->len >= hdrlen + 4)
1465                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1466         else
1467                 keyidx = -1;
1468
1469         if (net_ratelimit())
1470                 printk(KERN_DEBUG "%s: TKIP hwaccel reported Michael MIC "
1471                        "failure from %s to %s keyidx=%d\n",
1472                        dev->name, print_mac(mac, hdr->addr2),
1473                        print_mac(mac2, hdr->addr1), keyidx);
1474
1475         if (!rx->sta) {
1476                 /*
1477                  * Some hardware seem to generate incorrect Michael MIC
1478                  * reports; ignore them to avoid triggering countermeasures.
1479                  */
1480                 if (net_ratelimit())
1481                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1482                                "error for unknown address %s\n",
1483                                dev->name, print_mac(mac, hdr->addr2));
1484                 goto ignore;
1485         }
1486
1487         if (!(rx->fc & IEEE80211_FCTL_PROTECTED)) {
1488                 if (net_ratelimit())
1489                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1490                                "error for a frame with no PROTECTED flag (src "
1491                                "%s)\n", dev->name, print_mac(mac, hdr->addr2));
1492                 goto ignore;
1493         }
1494
1495         if (rx->sdata->vif.type == IEEE80211_IF_TYPE_AP && keyidx) {
1496                 /*
1497                  * APs with pairwise keys should never receive Michael MIC
1498                  * errors for non-zero keyidx because these are reserved for
1499                  * group keys and only the AP is sending real multicast
1500                  * frames in the BSS.
1501                  */
1502                 if (net_ratelimit())
1503                         printk(KERN_DEBUG "%s: ignored Michael MIC error for "
1504                                "a frame with non-zero keyidx (%d)"
1505                                " (src %s)\n", dev->name, keyidx,
1506                                print_mac(mac, hdr->addr2));
1507                 goto ignore;
1508         }
1509
1510         if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
1511             ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
1512              (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)) {
1513                 if (net_ratelimit())
1514                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1515                                "error for a frame that cannot be encrypted "
1516                                "(fc=0x%04x) (src %s)\n",
1517                                dev->name, rx->fc, print_mac(mac, hdr->addr2));
1518                 goto ignore;
1519         }
1520
1521         mac80211_ev_michael_mic_failure(rx->dev, keyidx, hdr);
1522  ignore:
1523         dev_kfree_skb(rx->skb);
1524         rx->skb = NULL;
1525 }
1526
1527 static void ieee80211_rx_cooked_monitor(struct ieee80211_txrx_data *rx)
1528 {
1529         struct ieee80211_sub_if_data *sdata;
1530         struct ieee80211_local *local = rx->local;
1531         struct ieee80211_rtap_hdr {
1532                 struct ieee80211_radiotap_header hdr;
1533                 u8 flags;
1534                 u8 rate;
1535                 __le16 chan_freq;
1536                 __le16 chan_flags;
1537         } __attribute__ ((packed)) *rthdr;
1538         struct sk_buff *skb = rx->skb, *skb2;
1539         struct net_device *prev_dev = NULL;
1540         struct ieee80211_rx_status *status = rx->u.rx.status;
1541
1542         if (rx->flags & IEEE80211_TXRXD_RX_CMNTR_REPORTED)
1543                 goto out_free_skb;
1544
1545         if (skb_headroom(skb) < sizeof(*rthdr) &&
1546             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
1547                 goto out_free_skb;
1548
1549         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
1550         memset(rthdr, 0, sizeof(*rthdr));
1551         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
1552         rthdr->hdr.it_present =
1553                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
1554                             (1 << IEEE80211_RADIOTAP_RATE) |
1555                             (1 << IEEE80211_RADIOTAP_CHANNEL));
1556
1557         rthdr->rate = rx->u.rx.rate->bitrate / 5;
1558         rthdr->chan_freq = cpu_to_le16(status->freq);
1559
1560         if (status->band == IEEE80211_BAND_5GHZ)
1561                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
1562                                                 IEEE80211_CHAN_5GHZ);
1563         else
1564                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
1565                                                 IEEE80211_CHAN_2GHZ);
1566
1567         skb_set_mac_header(skb, 0);
1568         skb->ip_summed = CHECKSUM_UNNECESSARY;
1569         skb->pkt_type = PACKET_OTHERHOST;
1570         skb->protocol = htons(ETH_P_802_2);
1571
1572         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1573                 if (!netif_running(sdata->dev))
1574                         continue;
1575
1576                 if (sdata->vif.type != IEEE80211_IF_TYPE_MNTR ||
1577                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
1578                         continue;
1579
1580                 if (prev_dev) {
1581                         skb2 = skb_clone(skb, GFP_ATOMIC);
1582                         if (skb2) {
1583                                 skb2->dev = prev_dev;
1584                                 netif_rx(skb2);
1585                         }
1586                 }
1587
1588                 prev_dev = sdata->dev;
1589                 sdata->dev->stats.rx_packets++;
1590                 sdata->dev->stats.rx_bytes += skb->len;
1591         }
1592
1593         if (prev_dev) {
1594                 skb->dev = prev_dev;
1595                 netif_rx(skb);
1596                 skb = NULL;
1597         } else
1598                 goto out_free_skb;
1599
1600         rx->flags |= IEEE80211_TXRXD_RX_CMNTR_REPORTED;
1601         return;
1602
1603  out_free_skb:
1604         dev_kfree_skb(skb);
1605 }
1606
1607 typedef ieee80211_rx_result (*ieee80211_rx_handler)(struct ieee80211_txrx_data *);
1608 static ieee80211_rx_handler ieee80211_rx_handlers[] =
1609 {
1610         ieee80211_rx_h_if_stats,
1611         ieee80211_rx_h_passive_scan,
1612         ieee80211_rx_h_check,
1613         ieee80211_rx_h_decrypt,
1614         ieee80211_rx_h_sta_process,
1615         ieee80211_rx_h_defragment,
1616         ieee80211_rx_h_ps_poll,
1617         ieee80211_rx_h_michael_mic_verify,
1618         /* this must be after decryption - so header is counted in MPDU mic
1619          * must be before pae and data, so QOS_DATA format frames
1620          * are not passed to user space by these functions
1621          */
1622         ieee80211_rx_h_remove_qos_control,
1623         ieee80211_rx_h_amsdu,
1624         ieee80211_rx_h_data,
1625         ieee80211_rx_h_ctrl,
1626         ieee80211_rx_h_mgmt,
1627         NULL
1628 };
1629
1630 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
1631                                          struct ieee80211_txrx_data *rx,
1632                                          struct sk_buff *skb)
1633 {
1634         ieee80211_rx_handler *handler;
1635         ieee80211_rx_result res = RX_DROP_MONITOR;
1636
1637         rx->skb = skb;
1638         rx->sdata = sdata;
1639         rx->dev = sdata->dev;
1640
1641         for (handler = ieee80211_rx_handlers; *handler != NULL; handler++) {
1642                 res = (*handler)(rx);
1643
1644                 switch (res) {
1645                 case RX_CONTINUE:
1646                         continue;
1647                 case RX_DROP_UNUSABLE:
1648                 case RX_DROP_MONITOR:
1649                         I802_DEBUG_INC(sdata->local->rx_handlers_drop);
1650                         if (rx->sta)
1651                                 rx->sta->rx_dropped++;
1652                         break;
1653                 case RX_QUEUED:
1654                         I802_DEBUG_INC(sdata->local->rx_handlers_queued);
1655                         break;
1656                 }
1657                 break;
1658         }
1659
1660         switch (res) {
1661         case RX_CONTINUE:
1662         case RX_DROP_MONITOR:
1663                 ieee80211_rx_cooked_monitor(rx);
1664                 break;
1665         case RX_DROP_UNUSABLE:
1666                 dev_kfree_skb(rx->skb);
1667                 break;
1668         }
1669 }
1670
1671 /* main receive path */
1672
1673 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
1674                                 u8 *bssid, struct ieee80211_txrx_data *rx,
1675                                 struct ieee80211_hdr *hdr)
1676 {
1677         int multicast = is_multicast_ether_addr(hdr->addr1);
1678
1679         switch (sdata->vif.type) {
1680         case IEEE80211_IF_TYPE_STA:
1681                 if (!bssid)
1682                         return 0;
1683                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1684                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1685                                 return 0;
1686                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1687                 } else if (!multicast &&
1688                            compare_ether_addr(sdata->dev->dev_addr,
1689                                               hdr->addr1) != 0) {
1690                         if (!(sdata->dev->flags & IFF_PROMISC))
1691                                 return 0;
1692                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1693                 }
1694                 break;
1695         case IEEE80211_IF_TYPE_IBSS:
1696                 if (!bssid)
1697                         return 0;
1698                 if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT &&
1699                     (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_BEACON)
1700                         return 1;
1701                 else if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1702                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1703                                 return 0;
1704                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1705                 } else if (!multicast &&
1706                            compare_ether_addr(sdata->dev->dev_addr,
1707                                               hdr->addr1) != 0) {
1708                         if (!(sdata->dev->flags & IFF_PROMISC))
1709                                 return 0;
1710                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1711                 } else if (!rx->sta)
1712                         rx->sta = ieee80211_ibss_add_sta(sdata->dev, rx->skb,
1713                                                          bssid, hdr->addr2);
1714                 break;
1715         case IEEE80211_IF_TYPE_VLAN:
1716         case IEEE80211_IF_TYPE_AP:
1717                 if (!bssid) {
1718                         if (compare_ether_addr(sdata->dev->dev_addr,
1719                                                hdr->addr1))
1720                                 return 0;
1721                 } else if (!ieee80211_bssid_match(bssid,
1722                                         sdata->dev->dev_addr)) {
1723                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1724                                 return 0;
1725                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1726                 }
1727                 if (sdata->dev == sdata->local->mdev &&
1728                     !(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1729                         /* do not receive anything via
1730                          * master device when not scanning */
1731                         return 0;
1732                 break;
1733         case IEEE80211_IF_TYPE_WDS:
1734                 if (bssid ||
1735                     (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
1736                         return 0;
1737                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
1738                         return 0;
1739                 break;
1740         case IEEE80211_IF_TYPE_MNTR:
1741                 /* take everything */
1742                 break;
1743         case IEEE80211_IF_TYPE_INVALID:
1744                 /* should never get here */
1745                 WARN_ON(1);
1746                 break;
1747         }
1748
1749         return 1;
1750 }
1751
1752 /*
1753  * This is the actual Rx frames handler. as it blongs to Rx path it must
1754  * be called with rcu_read_lock protection.
1755  */
1756 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
1757                                          struct sk_buff *skb,
1758                                          struct ieee80211_rx_status *status,
1759                                          u32 load,
1760                                          struct ieee80211_rate *rate)
1761 {
1762         struct ieee80211_local *local = hw_to_local(hw);
1763         struct ieee80211_sub_if_data *sdata;
1764         struct ieee80211_hdr *hdr;
1765         struct ieee80211_txrx_data rx;
1766         u16 type;
1767         int prepares;
1768         struct ieee80211_sub_if_data *prev = NULL;
1769         struct sk_buff *skb_new;
1770         u8 *bssid;
1771
1772         hdr = (struct ieee80211_hdr *) skb->data;
1773         memset(&rx, 0, sizeof(rx));
1774         rx.skb = skb;
1775         rx.local = local;
1776
1777         rx.u.rx.status = status;
1778         rx.u.rx.load = load;
1779         rx.u.rx.rate = rate;
1780         rx.fc = le16_to_cpu(hdr->frame_control);
1781         type = rx.fc & IEEE80211_FCTL_FTYPE;
1782
1783         if (type == IEEE80211_FTYPE_DATA || type == IEEE80211_FTYPE_MGMT)
1784                 local->dot11ReceivedFragmentCount++;
1785
1786         rx.sta = sta_info_get(local, hdr->addr2);
1787         if (rx.sta) {
1788                 rx.dev = rx.sta->dev;
1789                 rx.sdata = IEEE80211_DEV_TO_SUB_IF(rx.dev);
1790         }
1791
1792         if ((status->flag & RX_FLAG_MMIC_ERROR)) {
1793                 ieee80211_rx_michael_mic_report(local->mdev, hdr, &rx);
1794                 goto end;
1795         }
1796
1797         if (unlikely(local->sta_sw_scanning || local->sta_hw_scanning))
1798                 rx.flags |= IEEE80211_TXRXD_RXIN_SCAN;
1799
1800         ieee80211_parse_qos(&rx);
1801         ieee80211_verify_ip_alignment(&rx);
1802
1803         skb = rx.skb;
1804
1805         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1806                 if (!netif_running(sdata->dev))
1807                         continue;
1808
1809                 if (sdata->vif.type == IEEE80211_IF_TYPE_MNTR)
1810                         continue;
1811
1812                 bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
1813                 rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
1814                 prepares = prepare_for_handlers(sdata, bssid, &rx, hdr);
1815
1816                 if (!prepares)
1817                         continue;
1818
1819                 /*
1820                  * frame is destined for this interface, but if it's not
1821                  * also for the previous one we handle that after the
1822                  * loop to avoid copying the SKB once too much
1823                  */
1824
1825                 if (!prev) {
1826                         prev = sdata;
1827                         continue;
1828                 }
1829
1830                 /*
1831                  * frame was destined for the previous interface
1832                  * so invoke RX handlers for it
1833                  */
1834
1835                 skb_new = skb_copy(skb, GFP_ATOMIC);
1836                 if (!skb_new) {
1837                         if (net_ratelimit())
1838                                 printk(KERN_DEBUG "%s: failed to copy "
1839                                        "multicast frame for %s",
1840                                        wiphy_name(local->hw.wiphy),
1841                                        prev->dev->name);
1842                         continue;
1843                 }
1844                 rx.fc = le16_to_cpu(hdr->frame_control);
1845                 ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
1846                 prev = sdata;
1847         }
1848         if (prev) {
1849                 rx.fc = le16_to_cpu(hdr->frame_control);
1850                 ieee80211_invoke_rx_handlers(prev, &rx, skb);
1851         } else
1852                 dev_kfree_skb(skb);
1853
1854  end:
1855         if (rx.sta)
1856                 sta_info_put(rx.sta);
1857 }
1858
1859 #define SEQ_MODULO 0x1000
1860 #define SEQ_MASK   0xfff
1861
1862 static inline int seq_less(u16 sq1, u16 sq2)
1863 {
1864         return (((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1));
1865 }
1866
1867 static inline u16 seq_inc(u16 sq)
1868 {
1869         return ((sq + 1) & SEQ_MASK);
1870 }
1871
1872 static inline u16 seq_sub(u16 sq1, u16 sq2)
1873 {
1874         return ((sq1 - sq2) & SEQ_MASK);
1875 }
1876
1877
1878 /*
1879  * As it function blongs to Rx path it must be called with
1880  * the proper rcu_read_lock protection for its flow.
1881  */
1882 u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
1883                                 struct tid_ampdu_rx *tid_agg_rx,
1884                                 struct sk_buff *skb, u16 mpdu_seq_num,
1885                                 int bar_req)
1886 {
1887         struct ieee80211_local *local = hw_to_local(hw);
1888         struct ieee80211_rx_status status;
1889         u16 head_seq_num, buf_size;
1890         int index;
1891         u32 pkt_load;
1892         struct ieee80211_supported_band *sband;
1893         struct ieee80211_rate *rate;
1894
1895         buf_size = tid_agg_rx->buf_size;
1896         head_seq_num = tid_agg_rx->head_seq_num;
1897
1898         /* frame with out of date sequence number */
1899         if (seq_less(mpdu_seq_num, head_seq_num)) {
1900                 dev_kfree_skb(skb);
1901                 return 1;
1902         }
1903
1904         /* if frame sequence number exceeds our buffering window size or
1905          * block Ack Request arrived - release stored frames */
1906         if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
1907                 /* new head to the ordering buffer */
1908                 if (bar_req)
1909                         head_seq_num = mpdu_seq_num;
1910                 else
1911                         head_seq_num =
1912                                 seq_inc(seq_sub(mpdu_seq_num, buf_size));
1913                 /* release stored frames up to new head to stack */
1914                 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
1915                         index = seq_sub(tid_agg_rx->head_seq_num,
1916                                 tid_agg_rx->ssn)
1917                                 % tid_agg_rx->buf_size;
1918
1919                         if (tid_agg_rx->reorder_buf[index]) {
1920                                 /* release the reordered frames to stack */
1921                                 memcpy(&status,
1922                                         tid_agg_rx->reorder_buf[index]->cb,
1923                                         sizeof(status));
1924                                 sband = local->hw.wiphy->bands[status.band];
1925                                 rate = &sband->bitrates[status.rate_idx];
1926                                 pkt_load = ieee80211_rx_load_stats(local,
1927                                                 tid_agg_rx->reorder_buf[index],
1928                                                 &status, rate);
1929                                 __ieee80211_rx_handle_packet(hw,
1930                                         tid_agg_rx->reorder_buf[index],
1931                                         &status, pkt_load, rate);
1932                                 tid_agg_rx->stored_mpdu_num--;
1933                                 tid_agg_rx->reorder_buf[index] = NULL;
1934                         }
1935                         tid_agg_rx->head_seq_num =
1936                                 seq_inc(tid_agg_rx->head_seq_num);
1937                 }
1938                 if (bar_req)
1939                         return 1;
1940         }
1941
1942         /* now the new frame is always in the range of the reordering */
1943         /* buffer window */
1944         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
1945                                 % tid_agg_rx->buf_size;
1946         /* check if we already stored this frame */
1947         if (tid_agg_rx->reorder_buf[index]) {
1948                 dev_kfree_skb(skb);
1949                 return 1;
1950         }
1951
1952         /* if arrived mpdu is in the right order and nothing else stored */
1953         /* release it immediately */
1954         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
1955                         tid_agg_rx->stored_mpdu_num == 0) {
1956                 tid_agg_rx->head_seq_num =
1957                         seq_inc(tid_agg_rx->head_seq_num);
1958                 return 0;
1959         }
1960
1961         /* put the frame in the reordering buffer */
1962         tid_agg_rx->reorder_buf[index] = skb;
1963         tid_agg_rx->stored_mpdu_num++;
1964         /* release the buffer until next missing frame */
1965         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
1966                                                 % tid_agg_rx->buf_size;
1967         while (tid_agg_rx->reorder_buf[index]) {
1968                 /* release the reordered frame back to stack */
1969                 memcpy(&status, tid_agg_rx->reorder_buf[index]->cb,
1970                         sizeof(status));
1971                 sband = local->hw.wiphy->bands[status.band];
1972                 rate = &sband->bitrates[status.rate_idx];
1973                 pkt_load = ieee80211_rx_load_stats(local,
1974                                         tid_agg_rx->reorder_buf[index],
1975                                         &status, rate);
1976                 __ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index],
1977                                              &status, pkt_load, rate);
1978                 tid_agg_rx->stored_mpdu_num--;
1979                 tid_agg_rx->reorder_buf[index] = NULL;
1980                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
1981                 index = seq_sub(tid_agg_rx->head_seq_num,
1982                         tid_agg_rx->ssn) % tid_agg_rx->buf_size;
1983         }
1984         return 1;
1985 }
1986
1987 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
1988                                      struct sk_buff *skb)
1989 {
1990         struct ieee80211_hw *hw = &local->hw;
1991         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1992         struct sta_info *sta;
1993         struct tid_ampdu_rx *tid_agg_rx;
1994         u16 fc, sc;
1995         u16 mpdu_seq_num;
1996         u8 ret = 0, *qc;
1997         int tid;
1998
1999         sta = sta_info_get(local, hdr->addr2);
2000         if (!sta)
2001                 return ret;
2002
2003         fc = le16_to_cpu(hdr->frame_control);
2004
2005         /* filter the QoS data rx stream according to
2006          * STA/TID and check if this STA/TID is on aggregation */
2007         if (!WLAN_FC_IS_QOS_DATA(fc))
2008                 goto end_reorder;
2009
2010         qc = skb->data + ieee80211_get_hdrlen(fc) - QOS_CONTROL_LEN;
2011         tid = qc[0] & QOS_CONTROL_TID_MASK;
2012         tid_agg_rx = &(sta->ampdu_mlme.tid_rx[tid]);
2013
2014         if (tid_agg_rx->state != HT_AGG_STATE_OPERATIONAL)
2015                 goto end_reorder;
2016
2017         /* null data frames are excluded */
2018         if (unlikely(fc & IEEE80211_STYPE_NULLFUNC))
2019                 goto end_reorder;
2020
2021         /* new un-ordered ampdu frame - process it */
2022
2023         /* reset session timer */
2024         if (tid_agg_rx->timeout) {
2025                 unsigned long expires =
2026                         jiffies + (tid_agg_rx->timeout / 1000) * HZ;
2027                 mod_timer(&tid_agg_rx->session_timer, expires);
2028         }
2029
2030         /* if this mpdu is fragmented - terminate rx aggregation session */
2031         sc = le16_to_cpu(hdr->seq_ctrl);
2032         if (sc & IEEE80211_SCTL_FRAG) {
2033                 ieee80211_sta_stop_rx_ba_session(sta->dev, sta->addr,
2034                         tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
2035                 ret = 1;
2036                 goto end_reorder;
2037         }
2038
2039         /* according to mpdu sequence number deal with reordering buffer */
2040         mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
2041         ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb,
2042                                                 mpdu_seq_num, 0);
2043 end_reorder:
2044         if (sta)
2045                 sta_info_put(sta);
2046         return ret;
2047 }
2048
2049 /*
2050  * This is the receive path handler. It is called by a low level driver when an
2051  * 802.11 MPDU is received from the hardware.
2052  */
2053 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
2054                     struct ieee80211_rx_status *status)
2055 {
2056         struct ieee80211_local *local = hw_to_local(hw);
2057         u32 pkt_load;
2058         struct ieee80211_rate *rate = NULL;
2059         struct ieee80211_supported_band *sband;
2060
2061         if (status->band < 0 ||
2062             status->band > IEEE80211_NUM_BANDS) {
2063                 WARN_ON(1);
2064                 return;
2065         }
2066
2067         sband = local->hw.wiphy->bands[status->band];
2068
2069         if (!sband ||
2070             status->rate_idx < 0 ||
2071             status->rate_idx >= sband->n_bitrates) {
2072                 WARN_ON(1);
2073                 return;
2074         }
2075
2076         rate = &sband->bitrates[status->rate_idx];
2077
2078         /*
2079          * key references and virtual interfaces are protected using RCU
2080          * and this requires that we are in a read-side RCU section during
2081          * receive processing
2082          */
2083         rcu_read_lock();
2084
2085         /*
2086          * Frames with failed FCS/PLCP checksum are not returned,
2087          * all other frames are returned without radiotap header
2088          * if it was previously present.
2089          * Also, frames with less than 16 bytes are dropped.
2090          */
2091         skb = ieee80211_rx_monitor(local, skb, status, rate);
2092         if (!skb) {
2093                 rcu_read_unlock();
2094                 return;
2095         }
2096
2097         pkt_load = ieee80211_rx_load_stats(local, skb, status, rate);
2098         local->channel_use_raw += pkt_load;
2099
2100         if (!ieee80211_rx_reorder_ampdu(local, skb))
2101                 __ieee80211_rx_handle_packet(hw, skb, status, pkt_load, rate);
2102
2103         rcu_read_unlock();
2104 }
2105 EXPORT_SYMBOL(__ieee80211_rx);
2106
2107 /* This is a version of the rx handler that can be called from hard irq
2108  * context. Post the skb on the queue and schedule the tasklet */
2109 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
2110                           struct ieee80211_rx_status *status)
2111 {
2112         struct ieee80211_local *local = hw_to_local(hw);
2113
2114         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2115
2116         skb->dev = local->mdev;
2117         /* copy status into skb->cb for use by tasklet */
2118         memcpy(skb->cb, status, sizeof(*status));
2119         skb->pkt_type = IEEE80211_RX_MSG;
2120         skb_queue_tail(&local->skb_queue, skb);
2121         tasklet_schedule(&local->tasklet);
2122 }
2123 EXPORT_SYMBOL(ieee80211_rx_irqsafe);