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

   1 /*
   2  * Copyright 2002-2005, Instant802 Networks, Inc.
   3  * Copyright 2005-2006, Devicescape Software, Inc.
   4  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   5  * Copyright 2007       Johannes Berg <johannes@sipsolutions.net>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/skbuff.h>
  14 #include <linux/netdevice.h>
  15 #include <linux/etherdevice.h>
  16 #include <linux/rcupdate.h>
  17 #include <net/mac80211.h>
  18 #include <net/ieee80211_radiotap.h>
  19
  20 #include "ieee80211_i.h"
  21 #include "ieee80211_led.h"
  22 #include "wep.h"
  23 #include "wpa.h"
  24 #include "tkip.h"
  25 #include "wme.h"
  26
  27 u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
  28                                 struct tid_ampdu_rx *tid_agg_rx,
  29                                 struct sk_buff *skb, u16 mpdu_seq_num,
  30                                 int bar_req);
  31 /*
  32  * monitor mode reception
  33  *
  34  * This function cleans up the SKB, i.e. it removes all the stuff
  35  * only useful for monitoring.
  36  */
  37 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
  38                                            struct sk_buff *skb,
  39                                            int rtap_len)
  40 {
  41         skb_pull(skb, rtap_len);
  42
  43         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
  44                 if (likely(skb->len > FCS_LEN))
  45                         skb_trim(skb, skb->len - FCS_LEN);
  46                 else {
  47                         /* driver bug */
  48                         WARN_ON(1);
  49                         dev_kfree_skb(skb);
  50                         skb = NULL;
  51                 }
  52         }
  53
  54         return skb;
  55 }
  56
  57 static inline int should_drop_frame(struct ieee80211_rx_status *status,
  58                                     struct sk_buff *skb,
  59                                     int present_fcs_len,
  60                                     int radiotap_len)
  61 {
  62         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
  63
  64         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
  65                 return 1;
  66         if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len))
  67                 return 1;
  68         if (((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_FTYPE)) ==
  69                         cpu_to_le16(IEEE80211_FTYPE_CTL)) &&
  70             ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE)) !=
  71                         cpu_to_le16(IEEE80211_STYPE_PSPOLL)) &&
  72             ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE)) !=
  73                         cpu_to_le16(IEEE80211_STYPE_BACK_REQ)))
  74                 return 1;
  75         return 0;
  76 }
  77
  78 /*
  79  * This function copies a received frame to all monitor interfaces and
  80  * returns a cleaned-up SKB that no longer includes the FCS nor the
  81  * radiotap header the driver might have added.
  82  */
  83 static struct sk_buff *
  84 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
  85                      struct ieee80211_rx_status *status,
  86                      struct ieee80211_rate *rate)
  87 {
  88         struct ieee80211_sub_if_data *sdata;
  89         int needed_headroom = 0;
  90         struct ieee80211_radiotap_header *rthdr;
  91         __le64 *rttsft = NULL;
  92         struct ieee80211_rtap_fixed_data {
  93                 u8 flags;
  94                 u8 rate;
  95                 __le16 chan_freq;
  96                 __le16 chan_flags;
  97                 u8 antsignal;
  98                 u8 padding_for_rxflags;
  99                 __le16 rx_flags;
 100         } __attribute__ ((packed)) *rtfixed;
 101         struct sk_buff *skb, *skb2;
 102         struct net_device *prev_dev = NULL;
 103         int present_fcs_len = 0;
 104         int rtap_len = 0;
 105
 106         /*
 107          * First, we may need to make a copy of the skb because
 108          *  (1) we need to modify it for radiotap (if not present), and
 109          *  (2) the other RX handlers will modify the skb we got.
 110          *
 111          * We don't need to, of course, if we aren't going to return
 112          * the SKB because it has a bad FCS/PLCP checksum.
 113          */
 114         if (status->flag & RX_FLAG_RADIOTAP)
 115                 rtap_len = ieee80211_get_radiotap_len(origskb->data);
 116         else
 117                 /* room for radiotap header, always present fields and TSFT */
 118                 needed_headroom = sizeof(*rthdr) + sizeof(*rtfixed) + 8;
 119
 120         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 121                 present_fcs_len = FCS_LEN;
 122
 123         if (!local->monitors) {
 124                 if (should_drop_frame(status, origskb, present_fcs_len,
 125                                       rtap_len)) {
 126                         dev_kfree_skb(origskb);
 127                         return NULL;
 128                 }
 129
 130                 return remove_monitor_info(local, origskb, rtap_len);
 131         }
 132
 133         if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) {
 134                 /* only need to expand headroom if necessary */
 135                 skb = origskb;
 136                 origskb = NULL;
 137
 138                 /*
 139                  * This shouldn't trigger often because most devices have an
 140                  * RX header they pull before we get here, and that should
 141                  * be big enough for our radiotap information. We should
 142                  * probably export the length to drivers so that we can have
 143                  * them allocate enough headroom to start with.
 144                  */
 145                 if (skb_headroom(skb) < needed_headroom &&
 146                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
 147                         dev_kfree_skb(skb);
 148                         return NULL;
 149                 }
 150         } else {
 151                 /*
 152                  * Need to make a copy and possibly remove radiotap header
 153                  * and FCS from the original.
 154                  */
 155                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
 156
 157                 origskb = remove_monitor_info(local, origskb, rtap_len);
 158
 159                 if (!skb)
 160                         return origskb;
 161         }
 162
 163         /* if necessary, prepend radiotap information */
 164         if (!(status->flag & RX_FLAG_RADIOTAP)) {
 165                 rtfixed = (void *) skb_push(skb, sizeof(*rtfixed));
 166                 rtap_len = sizeof(*rthdr) + sizeof(*rtfixed);
 167                 if (status->flag & RX_FLAG_TSFT) {
 168                         rttsft = (void *) skb_push(skb, sizeof(*rttsft));
 169                         rtap_len += 8;
 170                 }
 171                 rthdr = (void *) skb_push(skb, sizeof(*rthdr));
 172                 memset(rthdr, 0, sizeof(*rthdr));
 173                 memset(rtfixed, 0, sizeof(*rtfixed));
 174                 rthdr->it_present =
 175                         cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 176                                     (1 << IEEE80211_RADIOTAP_RATE) |
 177                                     (1 << IEEE80211_RADIOTAP_CHANNEL) |
 178                                     (1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL) |
 179                                     (1 << IEEE80211_RADIOTAP_RX_FLAGS));
 180                 rtfixed->flags = 0;
 181                 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 182                         rtfixed->flags |= IEEE80211_RADIOTAP_F_FCS;
 183
 184                 if (rttsft) {
 185                         *rttsft = cpu_to_le64(status->mactime);
 186                         rthdr->it_present |=
 187                                 cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
 188                 }
 189
 190                 /* FIXME: when radiotap gets a 'bad PLCP' flag use it here */
 191                 rtfixed->rx_flags = 0;
 192                 if (status->flag &
 193                     (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 194                         rtfixed->rx_flags |=
 195                                 cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS);
 196
 197                 rtfixed->rate = rate->bitrate / 5;
 198
 199                 rtfixed->chan_freq = cpu_to_le16(status->freq);
 200
 201                 if (status->band == IEEE80211_BAND_5GHZ)
 202                         rtfixed->chan_flags =
 203                                 cpu_to_le16(IEEE80211_CHAN_OFDM |
 204                                             IEEE80211_CHAN_5GHZ);
 205                 else
 206                         rtfixed->chan_flags =
 207                                 cpu_to_le16(IEEE80211_CHAN_DYN |
 208                                             IEEE80211_CHAN_2GHZ);
 209
 210                 rtfixed->antsignal = status->ssi;
 211                 rthdr->it_len = cpu_to_le16(rtap_len);
 212         }
 213
 214         skb_reset_mac_header(skb);
 215         skb->ip_summed = CHECKSUM_UNNECESSARY;
 216         skb->pkt_type = PACKET_OTHERHOST;
 217         skb->protocol = htons(ETH_P_802_2);
 218
 219         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 220                 if (!netif_running(sdata->dev))
 221                         continue;
 222
 223                 if (sdata->vif.type != IEEE80211_IF_TYPE_MNTR)
 224                         continue;
 225
 226                 if (prev_dev) {
 227                         skb2 = skb_clone(skb, GFP_ATOMIC);
 228                         if (skb2) {
 229                                 skb2->dev = prev_dev;
 230                                 netif_rx(skb2);
 231                         }
 232                 }
 233
 234                 prev_dev = sdata->dev;
 235                 sdata->dev->stats.rx_packets++;
 236                 sdata->dev->stats.rx_bytes += skb->len;
 237         }
 238
 239         if (prev_dev) {
 240                 skb->dev = prev_dev;
 241                 netif_rx(skb);
 242         } else
 243                 dev_kfree_skb(skb);
 244
 245         return origskb;
 246 }
 247
 248
 249 static void ieee80211_parse_qos(struct ieee80211_txrx_data *rx)
 250 {
 251         u8 *data = rx->skb->data;
 252         int tid;
 253
 254         /* does the frame have a qos control field? */
 255         if (WLAN_FC_IS_QOS_DATA(rx->fc)) {
 256                 u8 *qc = data + ieee80211_get_hdrlen(rx->fc) - QOS_CONTROL_LEN;
 257                 /* frame has qos control */
 258                 tid = qc[0] & QOS_CONTROL_TID_MASK;
 259                 if (qc[0] & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
 260                         rx->flags |= IEEE80211_TXRXD_RX_AMSDU;
 261                 else
 262                         rx->flags &= ~IEEE80211_TXRXD_RX_AMSDU;
 263         } else {
 264                 if (unlikely((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT)) {
 265                         /* Separate TID for management frames */
 266                         tid = NUM_RX_DATA_QUEUES - 1;
 267                 } else {
 268                         /* no qos control present */
 269                         tid = 0; /* 802.1d - Best Effort */
 270                 }
 271         }
 272
 273         I802_DEBUG_INC(rx->local->wme_rx_queue[tid]);
 274         /* only a debug counter, sta might not be assigned properly yet */
 275         if (rx->sta)
 276                 I802_DEBUG_INC(rx->sta->wme_rx_queue[tid]);
 277
 278         rx->u.rx.queue = tid;
 279         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 280          * For now, set skb->priority to 0 for other cases. */
 281         rx->skb->priority = (tid > 7) ? 0 : tid;
 282 }
 283
 284 static void ieee80211_verify_ip_alignment(struct ieee80211_txrx_data *rx)
 285 {
 286 #ifdef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
 287         int hdrlen;
 288
 289         if (!WLAN_FC_DATA_PRESENT(rx->fc))
 290                 return;
 291
 292         /*
 293          * Drivers are required to align the payload data in a way that
 294          * guarantees that the contained IP header is aligned to a four-
 295          * byte boundary. In the case of regular frames, this simply means
 296          * aligning the payload to a four-byte boundary (because either
 297          * the IP header is directly contained, or IV/RFC1042 headers that
 298          * have a length divisible by four are in front of it.
 299          *
 300          * With A-MSDU frames, however, the payload data address must
 301          * yield two modulo four because there are 14-byte 802.3 headers
 302          * within the A-MSDU frames that push the IP header further back
 303          * to a multiple of four again. Thankfully, the specs were sane
 304          * enough this time around to require padding each A-MSDU subframe
 305          * to a length that is a multiple of four.
 306          *
 307          * Padding like atheros hardware adds which is inbetween the 802.11
 308          * header and the payload is not supported, the driver is required
 309          * to move the 802.11 header further back in that case.
 310          */
 311         hdrlen = ieee80211_get_hdrlen(rx->fc);
 312         if (rx->flags & IEEE80211_TXRXD_RX_AMSDU)
 313                 hdrlen += ETH_HLEN;
 314         WARN_ON_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3);
 315 #endif
 316 }
 317
 318
 319 static u32 ieee80211_rx_load_stats(struct ieee80211_local *local,
 320                                    struct sk_buff *skb,
 321                                    struct ieee80211_rx_status *status,
 322                                    struct ieee80211_rate *rate)
 323 {
 324         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 325         u32 load = 0, hdrtime;
 326
 327         /* Estimate total channel use caused by this frame */
 328
 329         /* 1 bit at 1 Mbit/s takes 1 usec; in channel_use values,
 330          * 1 usec = 1/8 * (1080 / 10) = 13.5 */
 331
 332         if (status->band == IEEE80211_BAND_5GHZ ||
 333             (status->band == IEEE80211_BAND_5GHZ &&
 334              rate->flags & IEEE80211_RATE_ERP_G))
 335                 hdrtime = CHAN_UTIL_HDR_SHORT;
 336         else
 337                 hdrtime = CHAN_UTIL_HDR_LONG;
 338
 339         load = hdrtime;
 340         if (!is_multicast_ether_addr(hdr->addr1))
 341                 load += hdrtime;
 342
 343         /* TODO: optimise again */
 344         load += skb->len * CHAN_UTIL_RATE_LCM / rate->bitrate;
 345
 346         /* Divide channel_use by 8 to avoid wrapping around the counter */
 347         load >>= CHAN_UTIL_SHIFT;
 348
 349         return load;
 350 }
 351
 352 /* rx handlers */
 353
 354 static ieee80211_rx_result
 355 ieee80211_rx_h_if_stats(struct ieee80211_txrx_data *rx)
 356 {
 357         if (rx->sta)
 358                 rx->sta->channel_use_raw += rx->u.rx.load;
 359         rx->sdata->channel_use_raw += rx->u.rx.load;
 360         return RX_CONTINUE;
 361 }
 362
 363 static ieee80211_rx_result
 364 ieee80211_rx_h_passive_scan(struct ieee80211_txrx_data *rx)
 365 {
 366         struct ieee80211_local *local = rx->local;
 367         struct sk_buff *skb = rx->skb;
 368
 369         if (unlikely(local->sta_hw_scanning))
 370                 return ieee80211_sta_rx_scan(rx->dev, skb, rx->u.rx.status);
 371
 372         if (unlikely(local->sta_sw_scanning)) {
 373                 /* drop all the other packets during a software scan anyway */
 374                 if (ieee80211_sta_rx_scan(rx->dev, skb, rx->u.rx.status)
 375                     != RX_QUEUED)
 376                         dev_kfree_skb(skb);
 377                 return RX_QUEUED;
 378         }
 379
 380         if (unlikely(rx->flags & IEEE80211_TXRXD_RXIN_SCAN)) {
 381                 /* scanning finished during invoking of handlers */
 382                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
 383                 return RX_DROP_UNUSABLE;
 384         }
 385
 386         return RX_CONTINUE;
 387 }
 388
 389 static ieee80211_rx_result
 390 ieee80211_rx_h_check(struct ieee80211_txrx_data *rx)
 391 {
 392         struct ieee80211_hdr *hdr;
 393         hdr = (struct ieee80211_hdr *) rx->skb->data;
 394
 395         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 396         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 397                 if (unlikely(rx->fc & IEEE80211_FCTL_RETRY &&
 398                              rx->sta->last_seq_ctrl[rx->u.rx.queue] ==
 399                              hdr->seq_ctrl)) {
 400                         if (rx->flags & IEEE80211_TXRXD_RXRA_MATCH) {
 401                                 rx->local->dot11FrameDuplicateCount++;
 402                                 rx->sta->num_duplicates++;
 403                         }
 404                         return RX_DROP_MONITOR;
 405                 } else
 406                         rx->sta->last_seq_ctrl[rx->u.rx.queue] = hdr->seq_ctrl;
 407         }
 408
 409         if (unlikely(rx->skb->len < 16)) {
 410                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 411                 return RX_DROP_MONITOR;
 412         }
 413
 414         /* Drop disallowed frame classes based on STA auth/assoc state;
 415          * IEEE 802.11, Chap 5.5.
 416          *
 417          * 80211.o does filtering only based on association state, i.e., it
 418          * drops Class 3 frames from not associated stations. hostapd sends
 419          * deauth/disassoc frames when needed. In addition, hostapd is
 420          * responsible for filtering on both auth and assoc states.
 421          */
 422         if (unlikely(((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA ||
 423                       ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_CTL &&
 424                        (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PSPOLL)) &&
 425                      rx->sdata->vif.type != IEEE80211_IF_TYPE_IBSS &&
 426                      (!rx->sta || !(rx->sta->flags & WLAN_STA_ASSOC)))) {
 427                 if ((!(rx->fc & IEEE80211_FCTL_FROMDS) &&
 428                      !(rx->fc & IEEE80211_FCTL_TODS) &&
 429                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA)
 430                     || !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
 431                         /* Drop IBSS frames and frames for other hosts
 432                          * silently. */
 433                         return RX_DROP_MONITOR;
 434                 }
 435
 436                 return RX_DROP_MONITOR;
 437         }
 438
 439         return RX_CONTINUE;
 440 }
 441
 442
 443 static ieee80211_rx_result
 444 ieee80211_rx_h_decrypt(struct ieee80211_txrx_data *rx)
 445 {
 446         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 447         int keyidx;
 448         int hdrlen;
 449         ieee80211_rx_result result = RX_DROP_UNUSABLE;
 450         struct ieee80211_key *stakey = NULL;
 451
 452         /*
 453          * Key selection 101
 454          *
 455          * There are three types of keys:
 456          *  - GTK (group keys)
 457          *  - PTK (pairwise keys)
 458          *  - STK (station-to-station pairwise keys)
 459          *
 460          * When selecting a key, we have to distinguish between multicast
 461          * (including broadcast) and unicast frames, the latter can only
 462          * use PTKs and STKs while the former always use GTKs. Unless, of
 463          * course, actual WEP keys ("pre-RSNA") are used, then unicast
 464          * frames can also use key indizes like GTKs. Hence, if we don't
 465          * have a PTK/STK we check the key index for a WEP key.
 466          *
 467          * Note that in a regular BSS, multicast frames are sent by the
 468          * AP only, associated stations unicast the frame to the AP first
 469          * which then multicasts it on their behalf.
 470          *
 471          * There is also a slight problem in IBSS mode: GTKs are negotiated
 472          * with each station, that is something we don't currently handle.
 473          * The spec seems to expect that one negotiates the same key with
 474          * every station but there's no such requirement; VLANs could be
 475          * possible.
 476          */
 477
 478         if (!(rx->fc & IEEE80211_FCTL_PROTECTED))
 479                 return RX_CONTINUE;
 480
 481         /*
 482          * No point in finding a key and decrypting if the frame is neither
 483          * addressed to us nor a multicast frame.
 484          */
 485         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 486                 return RX_CONTINUE;
 487
 488         if (rx->sta)
 489                 stakey = rcu_dereference(rx->sta->key);
 490
 491         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
 492                 rx->key = stakey;
 493         } else {
 494                 /*
 495                  * The device doesn't give us the IV so we won't be
 496                  * able to look up the key. That's ok though, we
 497                  * don't need to decrypt the frame, we just won't
 498                  * be able to keep statistics accurate.
 499                  * Except for key threshold notifications, should
 500                  * we somehow allow the driver to tell us which key
 501                  * the hardware used if this flag is set?
 502                  */
 503                 if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) &&
 504                     (rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED))
 505                         return RX_CONTINUE;
 506
 507                 hdrlen = ieee80211_get_hdrlen(rx->fc);
 508
 509                 if (rx->skb->len < 8 + hdrlen)
 510                         return RX_DROP_UNUSABLE; /* TODO: count this? */
 511
 512                 /*
 513                  * no need to call ieee80211_wep_get_keyidx,
 514                  * it verifies a bunch of things we've done already
 515                  */
 516                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
 517
 518                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
 519
 520                 /*
 521                  * RSNA-protected unicast frames should always be sent with
 522                  * pairwise or station-to-station keys, but for WEP we allow
 523                  * using a key index as well.
 524                  */
 525                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
 526                     !is_multicast_ether_addr(hdr->addr1))
 527                         rx->key = NULL;
 528         }
 529
 530         if (rx->key) {
 531                 rx->key->tx_rx_count++;
 532                 /* TODO: add threshold stuff again */
 533         } else {
 534 #ifdef CONFIG_MAC80211_DEBUG
 535                 if (net_ratelimit())
 536                         printk(KERN_DEBUG "%s: RX protected frame,"
 537                                " but have no key\n", rx->dev->name);
 538 #endif /* CONFIG_MAC80211_DEBUG */
 539                 return RX_DROP_MONITOR;
 540         }
 541
 542         /* Check for weak IVs if possible */
 543         if (rx->sta && rx->key->conf.alg == ALG_WEP &&
 544             ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) &&
 545             (!(rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED) ||
 546              !(rx->u.rx.status->flag & RX_FLAG_DECRYPTED)) &&
 547             ieee80211_wep_is_weak_iv(rx->skb, rx->key))
 548                 rx->sta->wep_weak_iv_count++;
 549
 550         switch (rx->key->conf.alg) {
 551         case ALG_WEP:
 552                 result = ieee80211_crypto_wep_decrypt(rx);
 553                 break;
 554         case ALG_TKIP:
 555                 result = ieee80211_crypto_tkip_decrypt(rx);
 556                 break;
 557         case ALG_CCMP:
 558                 result = ieee80211_crypto_ccmp_decrypt(rx);
 559                 break;
 560         }
 561
 562         /* either the frame has been decrypted or will be dropped */
 563         rx->u.rx.status->flag |= RX_FLAG_DECRYPTED;
 564
 565         return result;
 566 }
 567
 568 static void ap_sta_ps_start(struct net_device *dev, struct sta_info *sta)
 569 {
 570         struct ieee80211_sub_if_data *sdata;
 571         DECLARE_MAC_BUF(mac);
 572
 573         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 574
 575         if (sdata->bss)
 576                 atomic_inc(&sdata->bss->num_sta_ps);
 577         sta->flags |= WLAN_STA_PS;
 578         sta->pspoll = 0;
 579 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 580         printk(KERN_DEBUG "%s: STA %s aid %d enters power save mode\n",
 581                dev->name, print_mac(mac, sta->addr), sta->aid);
 582 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 583 }
 584
 585 static int ap_sta_ps_end(struct net_device *dev, struct sta_info *sta)
 586 {
 587         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 588         struct sk_buff *skb;
 589         int sent = 0;
 590         struct ieee80211_sub_if_data *sdata;
 591         struct ieee80211_tx_packet_data *pkt_data;
 592         DECLARE_MAC_BUF(mac);
 593
 594         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 595         if (sdata->bss)
 596                 atomic_dec(&sdata->bss->num_sta_ps);
 597         sta->flags &= ~(WLAN_STA_PS | WLAN_STA_TIM);
 598         sta->pspoll = 0;
 599         if (!skb_queue_empty(&sta->ps_tx_buf)) {
 600                 if (local->ops->set_tim)
 601                         local->ops->set_tim(local_to_hw(local), sta->aid, 0);
 602                 if (sdata->bss)
 603                         bss_tim_clear(local, sdata->bss, sta->aid);
 604         }
 605 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 606         printk(KERN_DEBUG "%s: STA %s aid %d exits power save mode\n",
 607                dev->name, print_mac(mac, sta->addr), sta->aid);
 608 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 609         /* Send all buffered frames to the station */
 610         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
 611                 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 612                 sent++;
 613                 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
 614                 dev_queue_xmit(skb);
 615         }
 616         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
 617                 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 618                 local->total_ps_buffered--;
 619                 sent++;
 620 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 621                 printk(KERN_DEBUG "%s: STA %s aid %d send PS frame "
 622                        "since STA not sleeping anymore\n", dev->name,
 623                        print_mac(mac, sta->addr), sta->aid);
 624 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 625                 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
 626                 dev_queue_xmit(skb);
 627         }
 628
 629         return sent;
 630 }
 631
 632 static ieee80211_rx_result
 633 ieee80211_rx_h_sta_process(struct ieee80211_txrx_data *rx)
 634 {
 635         struct sta_info *sta = rx->sta;
 636         struct net_device *dev = rx->dev;
 637         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 638
 639         if (!sta)
 640                 return RX_CONTINUE;
 641
 642         /* Update last_rx only for IBSS packets which are for the current
 643          * BSSID to avoid keeping the current IBSS network alive in cases where
 644          * other STAs are using different BSSID. */
 645         if (rx->sdata->vif.type == IEEE80211_IF_TYPE_IBSS) {
 646                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
 647                                                 IEEE80211_IF_TYPE_IBSS);
 648                 if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0)
 649                         sta->last_rx = jiffies;
 650         } else
 651         if (!is_multicast_ether_addr(hdr->addr1) ||
 652             rx->sdata->vif.type == IEEE80211_IF_TYPE_STA) {
 653                 /* Update last_rx only for unicast frames in order to prevent
 654                  * the Probe Request frames (the only broadcast frames from a
 655                  * STA in infrastructure mode) from keeping a connection alive.
 656                  */
 657                 sta->last_rx = jiffies;
 658         }
 659
 660         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 661                 return RX_CONTINUE;
 662
 663         sta->rx_fragments++;
 664         sta->rx_bytes += rx->skb->len;
 665         sta->last_rssi = rx->u.rx.status->ssi;
 666         sta->last_signal = rx->u.rx.status->signal;
 667         sta->last_noise = rx->u.rx.status->noise;
 668
 669         if (!(rx->fc & IEEE80211_FCTL_MOREFRAGS)) {
 670                 /* Change STA power saving mode only in the end of a frame
 671                  * exchange sequence */
 672                 if ((sta->flags & WLAN_STA_PS) && !(rx->fc & IEEE80211_FCTL_PM))
 673                         rx->u.rx.sent_ps_buffered += ap_sta_ps_end(dev, sta);
 674                 else if (!(sta->flags & WLAN_STA_PS) &&
 675                          (rx->fc & IEEE80211_FCTL_PM))
 676                         ap_sta_ps_start(dev, sta);
 677         }
 678
 679         /* Drop data::nullfunc frames silently, since they are used only to
 680          * control station power saving mode. */
 681         if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 682             (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_NULLFUNC) {
 683                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
 684                 /* Update counter and free packet here to avoid counting this
 685                  * as a dropped packed. */
 686                 sta->rx_packets++;
 687                 dev_kfree_skb(rx->skb);
 688                 return RX_QUEUED;
 689         }
 690
 691         return RX_CONTINUE;
 692 } /* ieee80211_rx_h_sta_process */
 693
 694 static inline struct ieee80211_fragment_entry *
 695 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
 696                          unsigned int frag, unsigned int seq, int rx_queue,
 697                          struct sk_buff **skb)
 698 {
 699         struct ieee80211_fragment_entry *entry;
 700         int idx;
 701
 702         idx = sdata->fragment_next;
 703         entry = &sdata->fragments[sdata->fragment_next++];
 704         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
 705                 sdata->fragment_next = 0;
 706
 707         if (!skb_queue_empty(&entry->skb_list)) {
 708 #ifdef CONFIG_MAC80211_DEBUG
 709                 struct ieee80211_hdr *hdr =
 710                         (struct ieee80211_hdr *) entry->skb_list.next->data;
 711                 DECLARE_MAC_BUF(mac);
 712                 DECLARE_MAC_BUF(mac2);
 713                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
 714                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
 715                        "addr1=%s addr2=%s\n",
 716                        sdata->dev->name, idx,
 717                        jiffies - entry->first_frag_time, entry->seq,
 718                        entry->last_frag, print_mac(mac, hdr->addr1),
 719                        print_mac(mac2, hdr->addr2));
 720 #endif /* CONFIG_MAC80211_DEBUG */
 721                 __skb_queue_purge(&entry->skb_list);
 722         }
 723
 724         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
 725         *skb = NULL;
 726         entry->first_frag_time = jiffies;
 727         entry->seq = seq;
 728         entry->rx_queue = rx_queue;
 729         entry->last_frag = frag;
 730         entry->ccmp = 0;
 731         entry->extra_len = 0;
 732
 733         return entry;
 734 }
 735
 736 static inline struct ieee80211_fragment_entry *
 737 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
 738                           u16 fc, unsigned int frag, unsigned int seq,
 739                           int rx_queue, struct ieee80211_hdr *hdr)
 740 {
 741         struct ieee80211_fragment_entry *entry;
 742         int i, idx;
 743
 744         idx = sdata->fragment_next;
 745         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
 746                 struct ieee80211_hdr *f_hdr;
 747                 u16 f_fc;
 748
 749                 idx--;
 750                 if (idx < 0)
 751                         idx = IEEE80211_FRAGMENT_MAX - 1;
 752
 753                 entry = &sdata->fragments[idx];
 754                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
 755                     entry->rx_queue != rx_queue ||
 756                     entry->last_frag + 1 != frag)
 757                         continue;
 758
 759                 f_hdr = (struct ieee80211_hdr *) entry->skb_list.next->data;
 760                 f_fc = le16_to_cpu(f_hdr->frame_control);
 761
 762                 if ((fc & IEEE80211_FCTL_FTYPE) != (f_fc & IEEE80211_FCTL_FTYPE) ||
 763                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
 764                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
 765                         continue;
 766
 767                 if (entry->first_frag_time + 2 * HZ < jiffies) {
 768                         __skb_queue_purge(&entry->skb_list);
 769                         continue;
 770                 }
 771                 return entry;
 772         }
 773
 774         return NULL;
 775 }
 776
 777 static ieee80211_rx_result
 778 ieee80211_rx_h_defragment(struct ieee80211_txrx_data *rx)
 779 {
 780         struct ieee80211_hdr *hdr;
 781         u16 sc;
 782         unsigned int frag, seq;
 783         struct ieee80211_fragment_entry *entry;
 784         struct sk_buff *skb;
 785         DECLARE_MAC_BUF(mac);
 786
 787         hdr = (struct ieee80211_hdr *) rx->skb->data;
 788         sc = le16_to_cpu(hdr->seq_ctrl);
 789         frag = sc & IEEE80211_SCTL_FRAG;
 790
 791         if (likely((!(rx->fc & IEEE80211_FCTL_MOREFRAGS) && frag == 0) ||
 792                    (rx->skb)->len < 24 ||
 793                    is_multicast_ether_addr(hdr->addr1))) {
 794                 /* not fragmented */
 795                 goto out;
 796         }
 797         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
 798
 799         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
 800
 801         if (frag == 0) {
 802                 /* This is the first fragment of a new frame. */
 803                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
 804                                                  rx->u.rx.queue, &(rx->skb));
 805                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
 806                     (rx->fc & IEEE80211_FCTL_PROTECTED)) {
 807                         /* Store CCMP PN so that we can verify that the next
 808                          * fragment has a sequential PN value. */
 809                         entry->ccmp = 1;
 810                         memcpy(entry->last_pn,
 811                                rx->key->u.ccmp.rx_pn[rx->u.rx.queue],
 812                                CCMP_PN_LEN);
 813                 }
 814                 return RX_QUEUED;
 815         }
 816
 817         /* This is a fragment for a frame that should already be pending in
 818          * fragment cache. Add this fragment to the end of the pending entry.
 819          */
 820         entry = ieee80211_reassemble_find(rx->sdata, rx->fc, frag, seq,
 821                                           rx->u.rx.queue, hdr);
 822         if (!entry) {
 823                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 824                 return RX_DROP_MONITOR;
 825         }
 826
 827         /* Verify that MPDUs within one MSDU have sequential PN values.
 828          * (IEEE 802.11i, 8.3.3.4.5) */
 829         if (entry->ccmp) {
 830                 int i;
 831                 u8 pn[CCMP_PN_LEN], *rpn;
 832                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
 833                         return RX_DROP_UNUSABLE;
 834                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
 835                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
 836                         pn[i]++;
 837                         if (pn[i])
 838                                 break;
 839                 }
 840                 rpn = rx->key->u.ccmp.rx_pn[rx->u.rx.queue];
 841                 if (memcmp(pn, rpn, CCMP_PN_LEN) != 0) {
 842                         if (net_ratelimit())
 843                                 printk(KERN_DEBUG "%s: defrag: CCMP PN not "
 844                                        "sequential A2=%s"
 845                                        " PN=%02x%02x%02x%02x%02x%02x "
 846                                        "(expected %02x%02x%02x%02x%02x%02x)\n",
 847                                        rx->dev->name, print_mac(mac, hdr->addr2),
 848                                        rpn[0], rpn[1], rpn[2], rpn[3], rpn[4],
 849                                        rpn[5], pn[0], pn[1], pn[2], pn[3],
 850                                        pn[4], pn[5]);
 851                         return RX_DROP_UNUSABLE;
 852                 }
 853                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
 854         }
 855
 856         skb_pull(rx->skb, ieee80211_get_hdrlen(rx->fc));
 857         __skb_queue_tail(&entry->skb_list, rx->skb);
 858         entry->last_frag = frag;
 859         entry->extra_len += rx->skb->len;
 860         if (rx->fc & IEEE80211_FCTL_MOREFRAGS) {
 861                 rx->skb = NULL;
 862                 return RX_QUEUED;
 863         }
 864
 865         rx->skb = __skb_dequeue(&entry->skb_list);
 866         if (skb_tailroom(rx->skb) < entry->extra_len) {
 867                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
 868                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
 869                                               GFP_ATOMIC))) {
 870                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 871                         __skb_queue_purge(&entry->skb_list);
 872                         return RX_DROP_UNUSABLE;
 873                 }
 874         }
 875         while ((skb = __skb_dequeue(&entry->skb_list))) {
 876                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
 877                 dev_kfree_skb(skb);
 878         }
 879
 880         /* Complete frame has been reassembled - process it now */
 881         rx->flags |= IEEE80211_TXRXD_FRAGMENTED;
 882
 883  out:
 884         if (rx->sta)
 885                 rx->sta->rx_packets++;
 886         if (is_multicast_ether_addr(hdr->addr1))
 887                 rx->local->dot11MulticastReceivedFrameCount++;
 888         else
 889                 ieee80211_led_rx(rx->local);
 890         return RX_CONTINUE;
 891 }
 892
 893 static ieee80211_rx_result
 894 ieee80211_rx_h_ps_poll(struct ieee80211_txrx_data *rx)
 895 {
 896         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
 897         struct sk_buff *skb;
 898         int no_pending_pkts;
 899         DECLARE_MAC_BUF(mac);
 900
 901         if (likely(!rx->sta ||
 902                    (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL ||
 903                    (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PSPOLL ||
 904                    !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)))
 905                 return RX_CONTINUE;
 906
 907         if ((sdata->vif.type != IEEE80211_IF_TYPE_AP) &&
 908             (sdata->vif.type != IEEE80211_IF_TYPE_VLAN))
 909                 return RX_DROP_UNUSABLE;
 910
 911         skb = skb_dequeue(&rx->sta->tx_filtered);
 912         if (!skb) {
 913                 skb = skb_dequeue(&rx->sta->ps_tx_buf);
 914                 if (skb)
 915                         rx->local->total_ps_buffered--;
 916         }
 917         no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
 918                 skb_queue_empty(&rx->sta->ps_tx_buf);
 919
 920         if (skb) {
 921                 struct ieee80211_hdr *hdr =
 922                         (struct ieee80211_hdr *) skb->data;
 923
 924                 /* tell TX path to send one frame even though the STA may
 925                  * still remain is PS mode after this frame exchange */
 926                 rx->sta->pspoll = 1;
 927
 928 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 929                 printk(KERN_DEBUG "STA %s aid %d: PS Poll (entries after %d)\n",
 930                        print_mac(mac, rx->sta->addr), rx->sta->aid,
 931                        skb_queue_len(&rx->sta->ps_tx_buf));
 932 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 933
 934                 /* Use MoreData flag to indicate whether there are more
 935                  * buffered frames for this STA */
 936                 if (no_pending_pkts) {
 937                         hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
 938                         rx->sta->flags &= ~WLAN_STA_TIM;
 939                 } else
 940                         hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
 941
 942                 dev_queue_xmit(skb);
 943
 944                 if (no_pending_pkts) {
 945                         if (rx->local->ops->set_tim)
 946                                 rx->local->ops->set_tim(local_to_hw(rx->local),
 947                                                        rx->sta->aid, 0);
 948                         if (rx->sdata->bss)
 949                                 bss_tim_clear(rx->local, rx->sdata->bss, rx->sta->aid);
 950                 }
 951 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 952         } else if (!rx->u.rx.sent_ps_buffered) {
 953                 printk(KERN_DEBUG "%s: STA %s sent PS Poll even "
 954                        "though there is no buffered frames for it\n",
 955                        rx->dev->name, print_mac(mac, rx->sta->addr));
 956 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 957
 958         }
 959
 960         /* Free PS Poll skb here instead of returning RX_DROP that would
 961          * count as an dropped frame. */
 962         dev_kfree_skb(rx->skb);
 963
 964         return RX_QUEUED;
 965 }
 966
 967 static ieee80211_rx_result
 968 ieee80211_rx_h_remove_qos_control(struct ieee80211_txrx_data *rx)
 969 {
 970         u16 fc = rx->fc;
 971         u8 *data = rx->skb->data;
 972         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) data;
 973
 974         if (!WLAN_FC_IS_QOS_DATA(fc))
 975                 return RX_CONTINUE;
 976
 977         /* remove the qos control field, update frame type and meta-data */
 978         memmove(data + 2, data, ieee80211_get_hdrlen(fc) - 2);
 979         hdr = (struct ieee80211_hdr *) skb_pull(rx->skb, 2);
 980         /* change frame type to non QOS */
 981         rx->fc = fc &= ~IEEE80211_STYPE_QOS_DATA;
 982         hdr->frame_control = cpu_to_le16(fc);
 983
 984         return RX_CONTINUE;
 985 }
 986
 987 static int
 988 ieee80211_802_1x_port_control(struct ieee80211_txrx_data *rx)
 989 {
 990         if (unlikely(!rx->sta || !(rx->sta->flags & WLAN_STA_AUTHORIZED))) {
 991 #ifdef CONFIG_MAC80211_DEBUG
 992                 if (net_ratelimit())
 993                         printk(KERN_DEBUG "%s: dropped frame "
 994                                "(unauthorized port)\n", rx->dev->name);
 995 #endif /* CONFIG_MAC80211_DEBUG */
 996                 return -EACCES;
 997         }
 998
 999         return 0;
1000 }
1001
1002 static int
1003 ieee80211_drop_unencrypted(struct ieee80211_txrx_data *rx)
1004 {
1005         /*
1006          * Pass through unencrypted frames if the hardware has
1007          * decrypted them already.
1008          */
1009         if (rx->u.rx.status->flag & RX_FLAG_DECRYPTED)
1010                 return 0;
1011
1012         /* Drop unencrypted frames if key is set. */
1013         if (unlikely(!(rx->fc & IEEE80211_FCTL_PROTECTED) &&
1014                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
1015                      (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
1016                      (rx->key || rx->sdata->drop_unencrypted))) {
1017                 if (net_ratelimit())
1018                         printk(KERN_DEBUG "%s: RX non-WEP frame, but expected "
1019                                "encryption\n", rx->dev->name);
1020                 return -EACCES;
1021         }
1022         return 0;
1023 }
1024
1025 static int
1026 ieee80211_data_to_8023(struct ieee80211_txrx_data *rx)
1027 {
1028         struct net_device *dev = rx->dev;
1029         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
1030         u16 fc, hdrlen, ethertype;
1031         u8 *payload;
1032         u8 dst[ETH_ALEN];
1033         u8 src[ETH_ALEN];
1034         struct sk_buff *skb = rx->skb;
1035         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1036         DECLARE_MAC_BUF(mac);
1037         DECLARE_MAC_BUF(mac2);
1038         DECLARE_MAC_BUF(mac3);
1039         DECLARE_MAC_BUF(mac4);
1040
1041         fc = rx->fc;
1042
1043         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1044                 return -1;
1045
1046         hdrlen = ieee80211_get_hdrlen(fc);
1047
1048         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
1049          * header
1050          * IEEE 802.11 address fields:
1051          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
1052          *   0     0   DA    SA    BSSID n/a
1053          *   0     1   DA    BSSID SA    n/a
1054          *   1     0   BSSID SA    DA    n/a
1055          *   1     1   RA    TA    DA    SA
1056          */
1057
1058         switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
1059         case IEEE80211_FCTL_TODS:
1060                 /* BSSID SA DA */
1061                 memcpy(dst, hdr->addr3, ETH_ALEN);
1062                 memcpy(src, hdr->addr2, ETH_ALEN);
1063
1064                 if (unlikely(sdata->vif.type != IEEE80211_IF_TYPE_AP &&
1065                              sdata->vif.type != IEEE80211_IF_TYPE_VLAN)) {
1066                         if (net_ratelimit())
1067                                 printk(KERN_DEBUG "%s: dropped ToDS frame "
1068                                        "(BSSID=%s SA=%s DA=%s)\n",
1069                                        dev->name,
1070                                        print_mac(mac, hdr->addr1),
1071                                        print_mac(mac2, hdr->addr2),
1072                                        print_mac(mac3, hdr->addr3));
1073                         return -1;
1074                 }
1075                 break;
1076         case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
1077                 /* RA TA DA SA */
1078                 memcpy(dst, hdr->addr3, ETH_ALEN);
1079                 memcpy(src, hdr->addr4, ETH_ALEN);
1080
1081                 if (unlikely(sdata->vif.type != IEEE80211_IF_TYPE_WDS)) {
1082                         if (net_ratelimit())
1083                                 printk(KERN_DEBUG "%s: dropped FromDS&ToDS "
1084                                        "frame (RA=%s TA=%s DA=%s SA=%s)\n",
1085                                        rx->dev->name,
1086                                        print_mac(mac, hdr->addr1),
1087                                        print_mac(mac2, hdr->addr2),
1088                                        print_mac(mac3, hdr->addr3),
1089                                        print_mac(mac4, hdr->addr4));
1090                         return -1;
1091                 }
1092                 break;
1093         case IEEE80211_FCTL_FROMDS:
1094                 /* DA BSSID SA */
1095                 memcpy(dst, hdr->addr1, ETH_ALEN);
1096                 memcpy(src, hdr->addr3, ETH_ALEN);
1097
1098                 if (sdata->vif.type != IEEE80211_IF_TYPE_STA ||
1099                     (is_multicast_ether_addr(dst) &&
1100                      !compare_ether_addr(src, dev->dev_addr)))
1101                         return -1;
1102                 break;
1103         case 0:
1104                 /* DA SA BSSID */
1105                 memcpy(dst, hdr->addr1, ETH_ALEN);
1106                 memcpy(src, hdr->addr2, ETH_ALEN);
1107
1108                 if (sdata->vif.type != IEEE80211_IF_TYPE_IBSS) {
1109                         if (net_ratelimit()) {
1110                                 printk(KERN_DEBUG "%s: dropped IBSS frame "
1111                                        "(DA=%s SA=%s BSSID=%s)\n",
1112                                        dev->name,
1113                                        print_mac(mac, hdr->addr1),
1114                                        print_mac(mac2, hdr->addr2),
1115                                        print_mac(mac3, hdr->addr3));
1116                         }
1117                         return -1;
1118                 }
1119                 break;
1120         }
1121
1122         if (unlikely(skb->len - hdrlen < 8)) {
1123                 if (net_ratelimit()) {
1124                         printk(KERN_DEBUG "%s: RX too short data frame "
1125                                "payload\n", dev->name);
1126                 }
1127                 return -1;
1128         }
1129
1130         payload = skb->data + hdrlen;
1131         ethertype = (payload[6] << 8) | payload[7];
1132
1133         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1134                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1135                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1136                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1137                  * replace EtherType */
1138                 skb_pull(skb, hdrlen + 6);
1139                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1140                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1141         } else {
1142                 struct ethhdr *ehdr;
1143                 __be16 len;
1144
1145                 skb_pull(skb, hdrlen);
1146                 len = htons(skb->len);
1147                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1148                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1149                 memcpy(ehdr->h_source, src, ETH_ALEN);
1150                 ehdr->h_proto = len;
1151         }
1152         return 0;
1153 }
1154
1155 /*
1156  * requires that rx->skb is a frame with ethernet header
1157  */
1158 static bool ieee80211_frame_allowed(struct ieee80211_txrx_data *rx)
1159 {
1160         static const u8 pae_group_addr[ETH_ALEN]
1161                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1162         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1163
1164         /*
1165          * Allow EAPOL frames to us/the PAE group address regardless
1166          * of whether the frame was encrypted or not.
1167          */
1168         if (ehdr->h_proto == htons(ETH_P_PAE) &&
1169             (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
1170              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1171                 return true;
1172
1173         if (ieee80211_802_1x_port_control(rx) ||
1174             ieee80211_drop_unencrypted(rx))
1175                 return false;
1176
1177         return true;
1178 }
1179
1180 /*
1181  * requires that rx->skb is a frame with ethernet header
1182  */
1183 static void
1184 ieee80211_deliver_skb(struct ieee80211_txrx_data *rx)
1185 {
1186         struct net_device *dev = rx->dev;
1187         struct ieee80211_local *local = rx->local;
1188         struct sk_buff *skb, *xmit_skb;
1189         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1190         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1191         struct sta_info *dsta;
1192
1193         skb = rx->skb;
1194         xmit_skb = NULL;
1195
1196         if (local->bridge_packets && (sdata->vif.type == IEEE80211_IF_TYPE_AP ||
1197                                       sdata->vif.type == IEEE80211_IF_TYPE_VLAN) &&
1198             (rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
1199                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1200                         /*
1201                          * send multicast frames both to higher layers in
1202                          * local net stack and back to the wireless medium
1203                          */
1204                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1205                         if (!xmit_skb && net_ratelimit())
1206                                 printk(KERN_DEBUG "%s: failed to clone "
1207                                        "multicast frame\n", dev->name);
1208                 } else {
1209                         dsta = sta_info_get(local, skb->data);
1210                         if (dsta && dsta->dev == dev) {
1211                                 /*
1212                                  * The destination station is associated to
1213                                  * this AP (in this VLAN), so send the frame
1214                                  * directly to it and do not pass it to local
1215                                  * net stack.
1216                                  */
1217                                 xmit_skb = skb;
1218                                 skb = NULL;
1219                         }
1220                         if (dsta)
1221                                 sta_info_put(dsta);
1222                 }
1223         }
1224
1225         if (skb) {
1226                 /* deliver to local stack */
1227                 skb->protocol = eth_type_trans(skb, dev);
1228                 memset(skb->cb, 0, sizeof(skb->cb));
1229                 netif_rx(skb);
1230         }
1231
1232         if (xmit_skb) {
1233                 /* send to wireless media */
1234                 xmit_skb->protocol = htons(ETH_P_802_3);
1235                 skb_reset_network_header(xmit_skb);
1236                 skb_reset_mac_header(xmit_skb);
1237                 dev_queue_xmit(xmit_skb);
1238         }
1239 }
1240
1241 static ieee80211_rx_result
1242 ieee80211_rx_h_amsdu(struct ieee80211_txrx_data *rx)
1243 {
1244         struct net_device *dev = rx->dev;
1245         struct ieee80211_local *local = rx->local;
1246         u16 fc, ethertype;
1247         u8 *payload;
1248         struct sk_buff *skb = rx->skb, *frame = NULL;
1249         const struct ethhdr *eth;
1250         int remaining, err;
1251         u8 dst[ETH_ALEN];
1252         u8 src[ETH_ALEN];
1253         DECLARE_MAC_BUF(mac);
1254
1255         fc = rx->fc;
1256         if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
1257                 return RX_CONTINUE;
1258
1259         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1260                 return RX_DROP_MONITOR;
1261
1262         if (!(rx->flags & IEEE80211_TXRXD_RX_AMSDU))
1263                 return RX_CONTINUE;
1264
1265         err = ieee80211_data_to_8023(rx);
1266         if (unlikely(err))
1267                 return RX_DROP_UNUSABLE;
1268
1269         skb->dev = dev;
1270
1271         dev->stats.rx_packets++;
1272         dev->stats.rx_bytes += skb->len;
1273
1274         /* skip the wrapping header */
1275         eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
1276         if (!eth)
1277                 return RX_DROP_UNUSABLE;
1278
1279         while (skb != frame) {
1280                 u8 padding;
1281                 __be16 len = eth->h_proto;
1282                 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
1283
1284                 remaining = skb->len;
1285                 memcpy(dst, eth->h_dest, ETH_ALEN);
1286                 memcpy(src, eth->h_source, ETH_ALEN);
1287
1288                 padding = ((4 - subframe_len) & 0x3);
1289                 /* the last MSDU has no padding */
1290                 if (subframe_len > remaining) {
1291                         printk(KERN_DEBUG "%s: wrong buffer size", dev->name);
1292                         return RX_DROP_UNUSABLE;
1293                 }
1294
1295                 skb_pull(skb, sizeof(struct ethhdr));
1296                 /* if last subframe reuse skb */
1297                 if (remaining <= subframe_len + padding)
1298                         frame = skb;
1299                 else {
1300                         frame = dev_alloc_skb(local->hw.extra_tx_headroom +
1301                                               subframe_len);
1302
1303                         if (frame == NULL)
1304                                 return RX_DROP_UNUSABLE;
1305
1306                         skb_reserve(frame, local->hw.extra_tx_headroom +
1307                                     sizeof(struct ethhdr));
1308                         memcpy(skb_put(frame, ntohs(len)), skb->data,
1309                                 ntohs(len));
1310
1311                         eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
1312                                                         padding);
1313                         if (!eth) {
1314                                 printk(KERN_DEBUG "%s: wrong buffer size ",
1315                                        dev->name);
1316                                 dev_kfree_skb(frame);
1317                                 return RX_DROP_UNUSABLE;
1318                         }
1319                 }
1320
1321                 skb_reset_network_header(frame);
1322                 frame->dev = dev;
1323                 frame->priority = skb->priority;
1324                 rx->skb = frame;
1325
1326                 payload = frame->data;
1327                 ethertype = (payload[6] << 8) | payload[7];
1328
1329                 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1330                             ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1331                            compare_ether_addr(payload,
1332                                               bridge_tunnel_header) == 0)) {
1333                         /* remove RFC1042 or Bridge-Tunnel
1334                          * encapsulation and replace EtherType */
1335                         skb_pull(frame, 6);
1336                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1337                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1338                 } else {
1339                         memcpy(skb_push(frame, sizeof(__be16)),
1340                                &len, sizeof(__be16));
1341                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1342                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1343                 }
1344
1345                 if (!ieee80211_frame_allowed(rx)) {
1346                         if (skb == frame) /* last frame */
1347                                 return RX_DROP_UNUSABLE;
1348                         dev_kfree_skb(frame);
1349                         continue;
1350                 }
1351
1352                 ieee80211_deliver_skb(rx);
1353         }
1354
1355         return RX_QUEUED;
1356 }
1357
1358 static ieee80211_rx_result
1359 ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
1360 {
1361         struct net_device *dev = rx->dev;
1362         u16 fc;
1363         int err;
1364
1365         fc = rx->fc;
1366         if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
1367                 return RX_CONTINUE;
1368
1369         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1370                 return RX_DROP_MONITOR;
1371
1372         err = ieee80211_data_to_8023(rx);
1373         if (unlikely(err))
1374                 return RX_DROP_UNUSABLE;
1375
1376         if (!ieee80211_frame_allowed(rx))
1377                 return RX_DROP_MONITOR;
1378
1379         rx->skb->dev = dev;
1380
1381         dev->stats.rx_packets++;
1382         dev->stats.rx_bytes += rx->skb->len;
1383
1384         ieee80211_deliver_skb(rx);
1385
1386         return RX_QUEUED;
1387 }
1388
1389 static ieee80211_rx_result
1390 ieee80211_rx_h_ctrl(struct ieee80211_txrx_data *rx)
1391 {
1392         struct ieee80211_local *local = rx->local;
1393         struct ieee80211_hw *hw = &local->hw;
1394         struct sk_buff *skb = rx->skb;
1395         struct ieee80211_bar *bar = (struct ieee80211_bar *) skb->data;
1396         struct tid_ampdu_rx *tid_agg_rx;
1397         u16 start_seq_num;
1398         u16 tid;
1399
1400         if (likely((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL))
1401                 return RX_CONTINUE;
1402
1403         if ((rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_BACK_REQ) {
1404                 if (!rx->sta)
1405                         return RX_CONTINUE;
1406                 tid = le16_to_cpu(bar->control) >> 12;
1407                 tid_agg_rx = &(rx->sta->ampdu_mlme.tid_rx[tid]);
1408                 if (tid_agg_rx->state != HT_AGG_STATE_OPERATIONAL)
1409                         return RX_CONTINUE;
1410
1411                 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1412
1413                 /* reset session timer */
1414                 if (tid_agg_rx->timeout) {
1415                         unsigned long expires =
1416                                 jiffies + (tid_agg_rx->timeout / 1000) * HZ;
1417                         mod_timer(&tid_agg_rx->session_timer, expires);
1418                 }
1419
1420                 /* manage reordering buffer according to requested */
1421                 /* sequence number */
1422                 rcu_read_lock();
1423                 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL,
1424                                                  start_seq_num, 1);
1425                 rcu_read_unlock();
1426                 return RX_DROP_UNUSABLE;
1427         }
1428
1429         return RX_CONTINUE;
1430 }
1431
1432 static ieee80211_rx_result
1433 ieee80211_rx_h_mgmt(struct ieee80211_txrx_data *rx)
1434 {
1435         struct ieee80211_sub_if_data *sdata;
1436
1437         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
1438                 return RX_DROP_MONITOR;
1439
1440         sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1441         if ((sdata->vif.type == IEEE80211_IF_TYPE_STA ||
1442              sdata->vif.type == IEEE80211_IF_TYPE_IBSS) &&
1443             !(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME))
1444                 ieee80211_sta_rx_mgmt(rx->dev, rx->skb, rx->u.rx.status);
1445         else
1446                 return RX_DROP_MONITOR;
1447
1448         return RX_QUEUED;
1449 }
1450
1451 static inline ieee80211_rx_result __ieee80211_invoke_rx_handlers(
1452                                 struct ieee80211_local *local,
1453                                 ieee80211_rx_handler *handlers,
1454                                 struct ieee80211_txrx_data *rx,
1455                                 struct sta_info *sta)
1456 {
1457         ieee80211_rx_handler *handler;
1458         ieee80211_rx_result res = RX_DROP_MONITOR;
1459
1460         for (handler = handlers; *handler != NULL; handler++) {
1461                 res = (*handler)(rx);
1462
1463                 switch (res) {
1464                 case RX_CONTINUE:
1465                         continue;
1466                 case RX_DROP_UNUSABLE:
1467                 case RX_DROP_MONITOR:
1468                         I802_DEBUG_INC(local->rx_handlers_drop);
1469                         if (sta)
1470                                 sta->rx_dropped++;
1471                         break;
1472                 case RX_QUEUED:
1473                         I802_DEBUG_INC(local->rx_handlers_queued);
1474                         break;
1475                 }
1476                 break;
1477         }
1478
1479         if (res == RX_DROP_UNUSABLE || res == RX_DROP_MONITOR)
1480                 dev_kfree_skb(rx->skb);
1481         return res;
1482 }
1483
1484 static inline void ieee80211_invoke_rx_handlers(struct ieee80211_local *local,
1485                                                 ieee80211_rx_handler *handlers,
1486                                                 struct ieee80211_txrx_data *rx,
1487                                                 struct sta_info *sta)
1488 {
1489         if (__ieee80211_invoke_rx_handlers(local, handlers, rx, sta) ==
1490             RX_CONTINUE)
1491                 dev_kfree_skb(rx->skb);
1492 }
1493
1494 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1495                                             struct ieee80211_hdr *hdr,
1496                                             struct sta_info *sta,
1497                                             struct ieee80211_txrx_data *rx)
1498 {
1499         int keyidx, hdrlen;
1500         DECLARE_MAC_BUF(mac);
1501         DECLARE_MAC_BUF(mac2);
1502
1503         hdrlen = ieee80211_get_hdrlen_from_skb(rx->skb);
1504         if (rx->skb->len >= hdrlen + 4)
1505                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1506         else
1507                 keyidx = -1;
1508
1509         if (net_ratelimit())
1510                 printk(KERN_DEBUG "%s: TKIP hwaccel reported Michael MIC "
1511                        "failure from %s to %s keyidx=%d\n",
1512                        dev->name, print_mac(mac, hdr->addr2),
1513                        print_mac(mac2, hdr->addr1), keyidx);
1514
1515         if (!sta) {
1516                 /*
1517                  * Some hardware seem to generate incorrect Michael MIC
1518                  * reports; ignore them to avoid triggering countermeasures.
1519                  */
1520                 if (net_ratelimit())
1521                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1522                                "error for unknown address %s\n",
1523                                dev->name, print_mac(mac, hdr->addr2));
1524                 goto ignore;
1525         }
1526
1527         if (!(rx->fc & IEEE80211_FCTL_PROTECTED)) {
1528                 if (net_ratelimit())
1529                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1530                                "error for a frame with no PROTECTED flag (src "
1531                                "%s)\n", dev->name, print_mac(mac, hdr->addr2));
1532                 goto ignore;
1533         }
1534
1535         if (rx->sdata->vif.type == IEEE80211_IF_TYPE_AP && keyidx) {
1536                 /*
1537                  * APs with pairwise keys should never receive Michael MIC
1538                  * errors for non-zero keyidx because these are reserved for
1539                  * group keys and only the AP is sending real multicast
1540                  * frames in the BSS.
1541                  */
1542                 if (net_ratelimit())
1543                         printk(KERN_DEBUG "%s: ignored Michael MIC error for "
1544                                "a frame with non-zero keyidx (%d)"
1545                                " (src %s)\n", dev->name, keyidx,
1546                                print_mac(mac, hdr->addr2));
1547                 goto ignore;
1548         }
1549
1550         if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
1551             ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
1552              (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)) {
1553                 if (net_ratelimit())
1554                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1555                                "error for a frame that cannot be encrypted "
1556                                "(fc=0x%04x) (src %s)\n",
1557                                dev->name, rx->fc, print_mac(mac, hdr->addr2));
1558                 goto ignore;
1559         }
1560
1561         mac80211_ev_michael_mic_failure(rx->dev, keyidx, hdr);
1562  ignore:
1563         dev_kfree_skb(rx->skb);
1564         rx->skb = NULL;
1565 }
1566
1567 ieee80211_rx_handler ieee80211_rx_handlers[] =
1568 {
1569         ieee80211_rx_h_if_stats,
1570         ieee80211_rx_h_passive_scan,
1571         ieee80211_rx_h_check,
1572         ieee80211_rx_h_decrypt,
1573         ieee80211_rx_h_sta_process,
1574         ieee80211_rx_h_defragment,
1575         ieee80211_rx_h_ps_poll,
1576         ieee80211_rx_h_michael_mic_verify,
1577         /* this must be after decryption - so header is counted in MPDU mic
1578          * must be before pae and data, so QOS_DATA format frames
1579          * are not passed to user space by these functions
1580          */
1581         ieee80211_rx_h_remove_qos_control,
1582         ieee80211_rx_h_amsdu,
1583         ieee80211_rx_h_data,
1584         ieee80211_rx_h_ctrl,
1585         ieee80211_rx_h_mgmt,
1586         NULL
1587 };
1588
1589 /* main receive path */
1590
1591 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
1592                                 u8 *bssid, struct ieee80211_txrx_data *rx,
1593                                 struct ieee80211_hdr *hdr)
1594 {
1595         int multicast = is_multicast_ether_addr(hdr->addr1);
1596
1597         switch (sdata->vif.type) {
1598         case IEEE80211_IF_TYPE_STA:
1599                 if (!bssid)
1600                         return 0;
1601                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1602                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1603                                 return 0;
1604                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1605                 } else if (!multicast &&
1606                            compare_ether_addr(sdata->dev->dev_addr,
1607                                               hdr->addr1) != 0) {
1608                         if (!(sdata->dev->flags & IFF_PROMISC))
1609                                 return 0;
1610                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1611                 }
1612                 break;
1613         case IEEE80211_IF_TYPE_IBSS:
1614                 if (!bssid)
1615                         return 0;
1616                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1617                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1618                                 return 0;
1619                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1620                 } else if (!multicast &&
1621                            compare_ether_addr(sdata->dev->dev_addr,
1622                                               hdr->addr1) != 0) {
1623                         if (!(sdata->dev->flags & IFF_PROMISC))
1624                                 return 0;
1625                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1626                 } else if (!rx->sta)
1627                         rx->sta = ieee80211_ibss_add_sta(sdata->dev, rx->skb,
1628                                                          bssid, hdr->addr2);
1629                 break;
1630         case IEEE80211_IF_TYPE_VLAN:
1631         case IEEE80211_IF_TYPE_AP:
1632                 if (!bssid) {
1633                         if (compare_ether_addr(sdata->dev->dev_addr,
1634                                                hdr->addr1))
1635                                 return 0;
1636                 } else if (!ieee80211_bssid_match(bssid,
1637                                         sdata->dev->dev_addr)) {
1638                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1639                                 return 0;
1640                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1641                 }
1642                 if (sdata->dev == sdata->local->mdev &&
1643                     !(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1644                         /* do not receive anything via
1645                          * master device when not scanning */
1646                         return 0;
1647                 break;
1648         case IEEE80211_IF_TYPE_WDS:
1649                 if (bssid ||
1650                     (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
1651                         return 0;
1652                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
1653                         return 0;
1654                 break;
1655         case IEEE80211_IF_TYPE_MNTR:
1656                 /* take everything */
1657                 break;
1658         case IEEE80211_IF_TYPE_INVALID:
1659                 /* should never get here */
1660                 WARN_ON(1);
1661                 break;
1662         }
1663
1664         return 1;
1665 }
1666
1667 /*
1668  * This is the actual Rx frames handler. as it blongs to Rx path it must
1669  * be called with rcu_read_lock protection.
1670  */
1671 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
1672                                          struct sk_buff *skb,
1673                                          struct ieee80211_rx_status *status,
1674                                          u32 load,
1675                                          struct ieee80211_rate *rate)
1676 {
1677         struct ieee80211_local *local = hw_to_local(hw);
1678         struct ieee80211_sub_if_data *sdata;
1679         struct sta_info *sta;
1680         struct ieee80211_hdr *hdr;
1681         struct ieee80211_txrx_data rx;
1682         u16 type;
1683         int prepares;
1684         struct ieee80211_sub_if_data *prev = NULL;
1685         struct sk_buff *skb_new;
1686         u8 *bssid;
1687
1688         hdr = (struct ieee80211_hdr *) skb->data;
1689         memset(&rx, 0, sizeof(rx));
1690         rx.skb = skb;
1691         rx.local = local;
1692
1693         rx.u.rx.status = status;
1694         rx.u.rx.load = load;
1695         rx.u.rx.rate = rate;
1696         rx.fc = le16_to_cpu(hdr->frame_control);
1697         type = rx.fc & IEEE80211_FCTL_FTYPE;
1698
1699         if (type == IEEE80211_FTYPE_DATA || type == IEEE80211_FTYPE_MGMT)
1700                 local->dot11ReceivedFragmentCount++;
1701
1702         sta = rx.sta = sta_info_get(local, hdr->addr2);
1703         if (sta) {
1704                 rx.dev = rx.sta->dev;
1705                 rx.sdata = IEEE80211_DEV_TO_SUB_IF(rx.dev);
1706         }
1707
1708         if ((status->flag & RX_FLAG_MMIC_ERROR)) {
1709                 ieee80211_rx_michael_mic_report(local->mdev, hdr, sta, &rx);
1710                 goto end;
1711         }
1712
1713         if (unlikely(local->sta_sw_scanning || local->sta_hw_scanning))
1714                 rx.flags |= IEEE80211_TXRXD_RXIN_SCAN;
1715
1716         ieee80211_parse_qos(&rx);
1717         ieee80211_verify_ip_alignment(&rx);
1718
1719         skb = rx.skb;
1720
1721         if (sta && !(sta->flags & (WLAN_STA_WDS | WLAN_STA_ASSOC_AP)) &&
1722             !atomic_read(&local->iff_promiscs) &&
1723             !is_multicast_ether_addr(hdr->addr1)) {
1724                 rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
1725                 ieee80211_invoke_rx_handlers(local, local->rx_handlers, &rx,
1726                                              rx.sta);
1727                 sta_info_put(sta);
1728                 return;
1729         }
1730
1731         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1732                 if (!netif_running(sdata->dev))
1733                         continue;
1734
1735                 if (sdata->vif.type == IEEE80211_IF_TYPE_MNTR)
1736                         continue;
1737
1738                 bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
1739                 rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
1740                 prepares = prepare_for_handlers(sdata, bssid, &rx, hdr);
1741                 /* prepare_for_handlers can change sta */
1742                 sta = rx.sta;
1743
1744                 if (!prepares)
1745                         continue;
1746
1747                 /*
1748                  * frame is destined for this interface, but if it's not
1749                  * also for the previous one we handle that after the
1750                  * loop to avoid copying the SKB once too much
1751                  */
1752
1753                 if (!prev) {
1754                         prev = sdata;
1755                         continue;
1756                 }
1757
1758                 /*
1759                  * frame was destined for the previous interface
1760                  * so invoke RX handlers for it
1761                  */
1762
1763                 skb_new = skb_copy(skb, GFP_ATOMIC);
1764                 if (!skb_new) {
1765                         if (net_ratelimit())
1766                                 printk(KERN_DEBUG "%s: failed to copy "
1767                                        "multicast frame for %s",
1768                                        wiphy_name(local->hw.wiphy),
1769                                        prev->dev->name);
1770                         continue;
1771                 }
1772                 rx.fc = le16_to_cpu(hdr->frame_control);
1773                 rx.skb = skb_new;
1774                 rx.dev = prev->dev;
1775                 rx.sdata = prev;
1776                 ieee80211_invoke_rx_handlers(local, local->rx_handlers,
1777                                              &rx, sta);
1778                 prev = sdata;
1779         }
1780         if (prev) {
1781                 rx.fc = le16_to_cpu(hdr->frame_control);
1782                 rx.skb = skb;
1783                 rx.dev = prev->dev;
1784                 rx.sdata = prev;
1785                 ieee80211_invoke_rx_handlers(local, local->rx_handlers,
1786                                              &rx, sta);
1787         } else
1788                 dev_kfree_skb(skb);
1789
1790  end:
1791         if (sta)
1792                 sta_info_put(sta);
1793 }
1794
1795 #define SEQ_MODULO 0x1000
1796 #define SEQ_MASK   0xfff
1797
1798 static inline int seq_less(u16 sq1, u16 sq2)
1799 {
1800         return (((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1));
1801 }
1802
1803 static inline u16 seq_inc(u16 sq)
1804 {
1805         return ((sq + 1) & SEQ_MASK);
1806 }
1807
1808 static inline u16 seq_sub(u16 sq1, u16 sq2)
1809 {
1810         return ((sq1 - sq2) & SEQ_MASK);
1811 }
1812
1813
1814 /*
1815  * As it function blongs to Rx path it must be called with
1816  * the proper rcu_read_lock protection for its flow.
1817  */
1818 u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
1819                                 struct tid_ampdu_rx *tid_agg_rx,
1820                                 struct sk_buff *skb, u16 mpdu_seq_num,
1821                                 int bar_req)
1822 {
1823         struct ieee80211_local *local = hw_to_local(hw);
1824         struct ieee80211_rx_status status;
1825         u16 head_seq_num, buf_size;
1826         int index;
1827         u32 pkt_load;
1828         struct ieee80211_supported_band *sband;
1829         struct ieee80211_rate *rate;
1830
1831         buf_size = tid_agg_rx->buf_size;
1832         head_seq_num = tid_agg_rx->head_seq_num;
1833
1834         /* frame with out of date sequence number */
1835         if (seq_less(mpdu_seq_num, head_seq_num)) {
1836                 dev_kfree_skb(skb);
1837                 return 1;
1838         }
1839
1840         /* if frame sequence number exceeds our buffering window size or
1841          * block Ack Request arrived - release stored frames */
1842         if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
1843                 /* new head to the ordering buffer */
1844                 if (bar_req)
1845                         head_seq_num = mpdu_seq_num;
1846                 else
1847                         head_seq_num =
1848                                 seq_inc(seq_sub(mpdu_seq_num, buf_size));
1849                 /* release stored frames up to new head to stack */
1850                 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
1851                         index = seq_sub(tid_agg_rx->head_seq_num,
1852                                 tid_agg_rx->ssn)
1853                                 % tid_agg_rx->buf_size;
1854
1855                         if (tid_agg_rx->reorder_buf[index]) {
1856                                 /* release the reordered frames to stack */
1857                                 memcpy(&status,
1858                                         tid_agg_rx->reorder_buf[index]->cb,
1859                                         sizeof(status));
1860                                 sband = local->hw.wiphy->bands[status.band];
1861                                 rate = &sband->bitrates[status.rate_idx];
1862                                 pkt_load = ieee80211_rx_load_stats(local,
1863                                                 tid_agg_rx->reorder_buf[index],
1864                                                 &status, rate);
1865                                 __ieee80211_rx_handle_packet(hw,
1866                                         tid_agg_rx->reorder_buf[index],
1867                                         &status, pkt_load, rate);
1868                                 tid_agg_rx->stored_mpdu_num--;
1869                                 tid_agg_rx->reorder_buf[index] = NULL;
1870                         }
1871                         tid_agg_rx->head_seq_num =
1872                                 seq_inc(tid_agg_rx->head_seq_num);
1873                 }
1874                 if (bar_req)
1875                         return 1;
1876         }
1877
1878         /* now the new frame is always in the range of the reordering */
1879         /* buffer window */
1880         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
1881                                 % tid_agg_rx->buf_size;
1882         /* check if we already stored this frame */
1883         if (tid_agg_rx->reorder_buf[index]) {
1884                 dev_kfree_skb(skb);
1885                 return 1;
1886         }
1887
1888         /* if arrived mpdu is in the right order and nothing else stored */
1889         /* release it immediately */
1890         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
1891                         tid_agg_rx->stored_mpdu_num == 0) {
1892                 tid_agg_rx->head_seq_num =
1893                         seq_inc(tid_agg_rx->head_seq_num);
1894                 return 0;
1895         }
1896
1897         /* put the frame in the reordering buffer */
1898         tid_agg_rx->reorder_buf[index] = skb;
1899         tid_agg_rx->stored_mpdu_num++;
1900         /* release the buffer until next missing frame */
1901         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
1902                                                 % tid_agg_rx->buf_size;
1903         while (tid_agg_rx->reorder_buf[index]) {
1904                 /* release the reordered frame back to stack */
1905                 memcpy(&status, tid_agg_rx->reorder_buf[index]->cb,
1906                         sizeof(status));
1907                 sband = local->hw.wiphy->bands[status.band];
1908                 rate = &sband->bitrates[status.rate_idx];
1909                 pkt_load = ieee80211_rx_load_stats(local,
1910                                         tid_agg_rx->reorder_buf[index],
1911                                         &status, rate);
1912                 __ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index],
1913                                              &status, pkt_load, rate);
1914                 tid_agg_rx->stored_mpdu_num--;
1915                 tid_agg_rx->reorder_buf[index] = NULL;
1916                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
1917                 index = seq_sub(tid_agg_rx->head_seq_num,
1918                         tid_agg_rx->ssn) % tid_agg_rx->buf_size;
1919         }
1920         return 1;
1921 }
1922
1923 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
1924                                      struct sk_buff *skb)
1925 {
1926         struct ieee80211_hw *hw = &local->hw;
1927         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1928         struct sta_info *sta;
1929         struct tid_ampdu_rx *tid_agg_rx;
1930         u16 fc, sc;
1931         u16 mpdu_seq_num;
1932         u8 ret = 0, *qc;
1933         int tid;
1934
1935         sta = sta_info_get(local, hdr->addr2);
1936         if (!sta)
1937                 return ret;
1938
1939         fc = le16_to_cpu(hdr->frame_control);
1940
1941         /* filter the QoS data rx stream according to
1942          * STA/TID and check if this STA/TID is on aggregation */
1943         if (!WLAN_FC_IS_QOS_DATA(fc))
1944                 goto end_reorder;
1945
1946         qc = skb->data + ieee80211_get_hdrlen(fc) - QOS_CONTROL_LEN;
1947         tid = qc[0] & QOS_CONTROL_TID_MASK;
1948         tid_agg_rx = &(sta->ampdu_mlme.tid_rx[tid]);
1949
1950         if (tid_agg_rx->state != HT_AGG_STATE_OPERATIONAL)
1951                 goto end_reorder;
1952
1953         /* null data frames are excluded */
1954         if (unlikely(fc & IEEE80211_STYPE_NULLFUNC))
1955                 goto end_reorder;
1956
1957         /* new un-ordered ampdu frame - process it */
1958
1959         /* reset session timer */
1960         if (tid_agg_rx->timeout) {
1961                 unsigned long expires =
1962                         jiffies + (tid_agg_rx->timeout / 1000) * HZ;
1963                 mod_timer(&tid_agg_rx->session_timer, expires);
1964         }
1965
1966         /* if this mpdu is fragmented - terminate rx aggregation session */
1967         sc = le16_to_cpu(hdr->seq_ctrl);
1968         if (sc & IEEE80211_SCTL_FRAG) {
1969                 ieee80211_sta_stop_rx_ba_session(sta->dev, sta->addr,
1970                         tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
1971                 ret = 1;
1972                 goto end_reorder;
1973         }
1974
1975         /* according to mpdu sequence number deal with reordering buffer */
1976         mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
1977         ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb,
1978                                                 mpdu_seq_num, 0);
1979 end_reorder:
1980         if (sta)
1981                 sta_info_put(sta);
1982         return ret;
1983 }
1984
1985 /*
1986  * This is the receive path handler. It is called by a low level driver when an
1987  * 802.11 MPDU is received from the hardware.
1988  */
1989 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
1990                     struct ieee80211_rx_status *status)
1991 {
1992         struct ieee80211_local *local = hw_to_local(hw);
1993         u32 pkt_load;
1994         struct ieee80211_rate *rate = NULL;
1995         struct ieee80211_supported_band *sband;
1996
1997         if (status->band < 0 ||
1998             status->band > IEEE80211_NUM_BANDS) {
1999                 WARN_ON(1);
2000                 return;
2001         }
2002
2003         sband = local->hw.wiphy->bands[status->band];
2004
2005         if (!sband ||
2006             status->rate_idx < 0 ||
2007             status->rate_idx >= sband->n_bitrates) {
2008                 WARN_ON(1);
2009                 return;
2010         }
2011
2012         rate = &sband->bitrates[status->rate_idx];
2013
2014         /*
2015          * key references and virtual interfaces are protected using RCU
2016          * and this requires that we are in a read-side RCU section during
2017          * receive processing
2018          */
2019         rcu_read_lock();
2020
2021         /*
2022          * Frames with failed FCS/PLCP checksum are not returned,
2023          * all other frames are returned without radiotap header
2024          * if it was previously present.
2025          * Also, frames with less than 16 bytes are dropped.
2026          */
2027         skb = ieee80211_rx_monitor(local, skb, status, rate);
2028         if (!skb) {
2029                 rcu_read_unlock();
2030                 return;
2031         }
2032
2033         pkt_load = ieee80211_rx_load_stats(local, skb, status, rate);
2034         local->channel_use_raw += pkt_load;
2035
2036         if (!ieee80211_rx_reorder_ampdu(local, skb))
2037                 __ieee80211_rx_handle_packet(hw, skb, status, pkt_load, rate);
2038
2039         rcu_read_unlock();
2040 }
2041 EXPORT_SYMBOL(__ieee80211_rx);
2042
2043 /* This is a version of the rx handler that can be called from hard irq
2044  * context. Post the skb on the queue and schedule the tasklet */
2045 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
2046                           struct ieee80211_rx_status *status)
2047 {
2048         struct ieee80211_local *local = hw_to_local(hw);
2049
2050         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2051
2052         skb->dev = local->mdev;
2053         /* copy status into skb->cb for use by tasklet */
2054         memcpy(skb->cb, status, sizeof(*status));
2055         skb->pkt_type = IEEE80211_RX_MSG;
2056         skb_queue_tail(&local->skb_queue, skb);
2057         tasklet_schedule(&local->tasklet);
2058 }
2059 EXPORT_SYMBOL(ieee80211_rx_irqsafe);