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 /*
  28  * monitor mode reception
  29  *
  30  * This function cleans up the SKB, i.e. it removes all the stuff
  31  * only useful for monitoring.
  32  */
  33 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
  34                                            struct sk_buff *skb,
  35                                            int rtap_len)
  36 {
  37         skb_pull(skb, rtap_len);
  38
  39         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
  40                 if (likely(skb->len > FCS_LEN))
  41                         skb_trim(skb, skb->len - FCS_LEN);
  42                 else {
  43                         /* driver bug */
  44                         WARN_ON(1);
  45                         dev_kfree_skb(skb);
  46                         skb = NULL;
  47                 }
  48         }
  49
  50         return skb;
  51 }
  52
  53 static inline int should_drop_frame(struct ieee80211_rx_status *status,
  54                                     struct sk_buff *skb,
  55                                     int present_fcs_len,
  56                                     int radiotap_len)
  57 {
  58         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
  59
  60         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
  61                 return 1;
  62         if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len))
  63                 return 1;
  64         if ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_FTYPE)) ==
  65                         cpu_to_le16(IEEE80211_FTYPE_CTL))
  66                 return 1;
  67         return 0;
  68 }
  69
  70 /*
  71  * This function copies a received frame to all monitor interfaces and
  72  * returns a cleaned-up SKB that no longer includes the FCS nor the
  73  * radiotap header the driver might have added.
  74  */
  75 static struct sk_buff *
  76 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
  77                      struct ieee80211_rx_status *status)
  78 {
  79         struct ieee80211_sub_if_data *sdata;
  80         struct ieee80211_rate *rate;
  81         int needed_headroom = 0;
  82         struct ieee80211_rtap_hdr {
  83                 struct ieee80211_radiotap_header hdr;
  84                 u8 flags;
  85                 u8 rate;
  86                 __le16 chan_freq;
  87                 __le16 chan_flags;
  88                 u8 antsignal;
  89                 u8 padding_for_rxflags;
  90                 __le16 rx_flags;
  91         } __attribute__ ((packed)) *rthdr;
  92         struct sk_buff *skb, *skb2;
  93         struct net_device *prev_dev = NULL;
  94         int present_fcs_len = 0;
  95         int rtap_len = 0;
  96
  97         /*
  98          * First, we may need to make a copy of the skb because
  99          *  (1) we need to modify it for radiotap (if not present), and
 100          *  (2) the other RX handlers will modify the skb we got.
 101          *
 102          * We don't need to, of course, if we aren't going to return
 103          * the SKB because it has a bad FCS/PLCP checksum.
 104          */
 105         if (status->flag & RX_FLAG_RADIOTAP)
 106                 rtap_len = ieee80211_get_radiotap_len(origskb->data);
 107         else
 108                 needed_headroom = sizeof(*rthdr);
 109
 110         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 111                 present_fcs_len = FCS_LEN;
 112
 113         if (!local->monitors) {
 114                 if (should_drop_frame(status, origskb, present_fcs_len,
 115                                       rtap_len)) {
 116                         dev_kfree_skb(origskb);
 117                         return NULL;
 118                 }
 119
 120                 return remove_monitor_info(local, origskb, rtap_len);
 121         }
 122
 123         if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) {
 124                 /* only need to expand headroom if necessary */
 125                 skb = origskb;
 126                 origskb = NULL;
 127
 128                 /*
 129                  * This shouldn't trigger often because most devices have an
 130                  * RX header they pull before we get here, and that should
 131                  * be big enough for our radiotap information. We should
 132                  * probably export the length to drivers so that we can have
 133                  * them allocate enough headroom to start with.
 134                  */
 135                 if (skb_headroom(skb) < needed_headroom &&
 136                     pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC)) {
 137                         dev_kfree_skb(skb);
 138                         return NULL;
 139                 }
 140         } else {
 141                 /*
 142                  * Need to make a copy and possibly remove radiotap header
 143                  * and FCS from the original.
 144                  */
 145                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
 146
 147                 origskb = remove_monitor_info(local, origskb, rtap_len);
 148
 149                 if (!skb)
 150                         return origskb;
 151         }
 152
 153         /* if necessary, prepend radiotap information */
 154         if (!(status->flag & RX_FLAG_RADIOTAP)) {
 155                 rthdr = (void *) skb_push(skb, sizeof(*rthdr));
 156                 memset(rthdr, 0, sizeof(*rthdr));
 157                 rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
 158                 rthdr->hdr.it_present =
 159                         cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 160                                     (1 << IEEE80211_RADIOTAP_RATE) |
 161                                     (1 << IEEE80211_RADIOTAP_CHANNEL) |
 162                                     (1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL) |
 163                                     (1 << IEEE80211_RADIOTAP_RX_FLAGS));
 164                 rthdr->flags = local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS ?
 165                                IEEE80211_RADIOTAP_F_FCS : 0;
 166
 167                 /* FIXME: when radiotap gets a 'bad PLCP' flag use it here */
 168                 rthdr->rx_flags = 0;
 169                 if (status->flag &
 170                     (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 171                         rthdr->rx_flags |=
 172                                 cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS);
 173
 174                 rate = ieee80211_get_rate(local, status->phymode,
 175                                           status->rate);
 176                 if (rate)
 177                         rthdr->rate = rate->rate / 5;
 178
 179                 rthdr->chan_freq = cpu_to_le16(status->freq);
 180
 181                 if (status->phymode == MODE_IEEE80211A)
 182                         rthdr->chan_flags =
 183                                 cpu_to_le16(IEEE80211_CHAN_OFDM |
 184                                             IEEE80211_CHAN_5GHZ);
 185                 else
 186                         rthdr->chan_flags =
 187                                 cpu_to_le16(IEEE80211_CHAN_DYN |
 188                                             IEEE80211_CHAN_2GHZ);
 189
 190                 rthdr->antsignal = status->ssi;
 191         }
 192
 193         skb_set_mac_header(skb, 0);
 194         skb->ip_summed = CHECKSUM_UNNECESSARY;
 195         skb->pkt_type = PACKET_OTHERHOST;
 196         skb->protocol = htons(ETH_P_802_2);
 197
 198         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 199                 if (!netif_running(sdata->dev))
 200                         continue;
 201
 202                 if (sdata->type != IEEE80211_IF_TYPE_MNTR)
 203                         continue;
 204
 205                 if (prev_dev) {
 206                         skb2 = skb_clone(skb, GFP_ATOMIC);
 207                         if (skb2) {
 208                                 skb2->dev = prev_dev;
 209                                 netif_rx(skb2);
 210                         }
 211                 }
 212
 213                 prev_dev = sdata->dev;
 214                 sdata->dev->stats.rx_packets++;
 215                 sdata->dev->stats.rx_bytes += skb->len;
 216         }
 217
 218         if (prev_dev) {
 219                 skb->dev = prev_dev;
 220                 netif_rx(skb);
 221         } else
 222                 dev_kfree_skb(skb);
 223
 224         return origskb;
 225 }
 226
 227
 228 /* pre-rx handlers
 229  *
 230  * these don't have dev/sdata fields in the rx data
 231  * The sta value should also not be used because it may
 232  * be NULL even though a STA (in IBSS mode) will be added.
 233  */
 234
 235 static ieee80211_txrx_result
 236 ieee80211_rx_h_parse_qos(struct ieee80211_txrx_data *rx)
 237 {
 238         u8 *data = rx->skb->data;
 239         int tid;
 240
 241         /* does the frame have a qos control field? */
 242         if (WLAN_FC_IS_QOS_DATA(rx->fc)) {
 243                 u8 *qc = data + ieee80211_get_hdrlen(rx->fc) - QOS_CONTROL_LEN;
 244                 /* frame has qos control */
 245                 tid = qc[0] & QOS_CONTROL_TID_MASK;
 246         } else {
 247                 if (unlikely((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT)) {
 248                         /* Separate TID for management frames */
 249                         tid = NUM_RX_DATA_QUEUES - 1;
 250                 } else {
 251                         /* no qos control present */
 252                         tid = 0; /* 802.1d - Best Effort */
 253                 }
 254         }
 255
 256         I802_DEBUG_INC(rx->local->wme_rx_queue[tid]);
 257         /* only a debug counter, sta might not be assigned properly yet */
 258         if (rx->sta)
 259                 I802_DEBUG_INC(rx->sta->wme_rx_queue[tid]);
 260
 261         rx->u.rx.queue = tid;
 262         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 263          * For now, set skb->priority to 0 for other cases. */
 264         rx->skb->priority = (tid > 7) ? 0 : tid;
 265
 266         return TXRX_CONTINUE;
 267 }
 268
 269 static ieee80211_txrx_result
 270 ieee80211_rx_h_load_stats(struct ieee80211_txrx_data *rx)
 271 {
 272         struct ieee80211_local *local = rx->local;
 273         struct sk_buff *skb = rx->skb;
 274         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 275         u32 load = 0, hdrtime;
 276         struct ieee80211_rate *rate;
 277         struct ieee80211_hw_mode *mode = local->hw.conf.mode;
 278         int i;
 279
 280         /* Estimate total channel use caused by this frame */
 281
 282         if (unlikely(mode->num_rates < 0))
 283                 return TXRX_CONTINUE;
 284
 285         rate = &mode->rates[0];
 286         for (i = 0; i < mode->num_rates; i++) {
 287                 if (mode->rates[i].val == rx->u.rx.status->rate) {
 288                         rate = &mode->rates[i];
 289                         break;
 290                 }
 291         }
 292
 293         /* 1 bit at 1 Mbit/s takes 1 usec; in channel_use values,
 294          * 1 usec = 1/8 * (1080 / 10) = 13.5 */
 295
 296         if (mode->mode == MODE_IEEE80211A ||
 297             (mode->mode == MODE_IEEE80211G &&
 298              rate->flags & IEEE80211_RATE_ERP))
 299                 hdrtime = CHAN_UTIL_HDR_SHORT;
 300         else
 301                 hdrtime = CHAN_UTIL_HDR_LONG;
 302
 303         load = hdrtime;
 304         if (!is_multicast_ether_addr(hdr->addr1))
 305                 load += hdrtime;
 306
 307         load += skb->len * rate->rate_inv;
 308
 309         /* Divide channel_use by 8 to avoid wrapping around the counter */
 310         load >>= CHAN_UTIL_SHIFT;
 311         local->channel_use_raw += load;
 312         rx->u.rx.load = load;
 313
 314         return TXRX_CONTINUE;
 315 }
 316
 317 ieee80211_rx_handler ieee80211_rx_pre_handlers[] =
 318 {
 319         ieee80211_rx_h_parse_qos,
 320         ieee80211_rx_h_load_stats,
 321         NULL
 322 };
 323
 324 /* rx handlers */
 325
 326 static ieee80211_txrx_result
 327 ieee80211_rx_h_if_stats(struct ieee80211_txrx_data *rx)
 328 {
 329         if (rx->sta)
 330                 rx->sta->channel_use_raw += rx->u.rx.load;
 331         rx->sdata->channel_use_raw += rx->u.rx.load;
 332         return TXRX_CONTINUE;
 333 }
 334
 335 static ieee80211_txrx_result
 336 ieee80211_rx_h_passive_scan(struct ieee80211_txrx_data *rx)
 337 {
 338         struct ieee80211_local *local = rx->local;
 339         struct sk_buff *skb = rx->skb;
 340
 341         if (unlikely(local->sta_scanning != 0)) {
 342                 ieee80211_sta_rx_scan(rx->dev, skb, rx->u.rx.status);
 343                 return TXRX_QUEUED;
 344         }
 345
 346         if (unlikely(rx->flags & IEEE80211_TXRXD_RXIN_SCAN)) {
 347                 /* scanning finished during invoking of handlers */
 348                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
 349                 return TXRX_DROP;
 350         }
 351
 352         return TXRX_CONTINUE;
 353 }
 354
 355 static ieee80211_txrx_result
 356 ieee80211_rx_h_check(struct ieee80211_txrx_data *rx)
 357 {
 358         struct ieee80211_hdr *hdr;
 359         hdr = (struct ieee80211_hdr *) rx->skb->data;
 360
 361         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 362         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 363                 if (unlikely(rx->fc & IEEE80211_FCTL_RETRY &&
 364                              rx->sta->last_seq_ctrl[rx->u.rx.queue] ==
 365                              hdr->seq_ctrl)) {
 366                         if (rx->flags & IEEE80211_TXRXD_RXRA_MATCH) {
 367                                 rx->local->dot11FrameDuplicateCount++;
 368                                 rx->sta->num_duplicates++;
 369                         }
 370                         return TXRX_DROP;
 371                 } else
 372                         rx->sta->last_seq_ctrl[rx->u.rx.queue] = hdr->seq_ctrl;
 373         }
 374
 375         if (unlikely(rx->skb->len < 16)) {
 376                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 377                 return TXRX_DROP;
 378         }
 379
 380         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 381                 rx->skb->pkt_type = PACKET_OTHERHOST;
 382         else if (compare_ether_addr(rx->dev->dev_addr, hdr->addr1) == 0)
 383                 rx->skb->pkt_type = PACKET_HOST;
 384         else if (is_multicast_ether_addr(hdr->addr1)) {
 385                 if (is_broadcast_ether_addr(hdr->addr1))
 386                         rx->skb->pkt_type = PACKET_BROADCAST;
 387                 else
 388                         rx->skb->pkt_type = PACKET_MULTICAST;
 389         } else
 390                 rx->skb->pkt_type = PACKET_OTHERHOST;
 391
 392         /* Drop disallowed frame classes based on STA auth/assoc state;
 393          * IEEE 802.11, Chap 5.5.
 394          *
 395          * 80211.o does filtering only based on association state, i.e., it
 396          * drops Class 3 frames from not associated stations. hostapd sends
 397          * deauth/disassoc frames when needed. In addition, hostapd is
 398          * responsible for filtering on both auth and assoc states.
 399          */
 400         if (unlikely(((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA ||
 401                       ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_CTL &&
 402                        (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PSPOLL)) &&
 403                      rx->sdata->type != IEEE80211_IF_TYPE_IBSS &&
 404                      (!rx->sta || !(rx->sta->flags & WLAN_STA_ASSOC)))) {
 405                 if ((!(rx->fc & IEEE80211_FCTL_FROMDS) &&
 406                      !(rx->fc & IEEE80211_FCTL_TODS) &&
 407                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA)
 408                     || !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
 409                         /* Drop IBSS frames and frames for other hosts
 410                          * silently. */
 411                         return TXRX_DROP;
 412                 }
 413
 414                 return TXRX_DROP;
 415         }
 416
 417         return TXRX_CONTINUE;
 418 }
 419
 420
 421 static ieee80211_txrx_result
 422 ieee80211_rx_h_decrypt(struct ieee80211_txrx_data *rx)
 423 {
 424         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 425         int keyidx;
 426         int hdrlen;
 427         struct ieee80211_key *stakey = NULL;
 428
 429         /*
 430          * Key selection 101
 431          *
 432          * There are three types of keys:
 433          *  - GTK (group keys)
 434          *  - PTK (pairwise keys)
 435          *  - STK (station-to-station pairwise keys)
 436          *
 437          * When selecting a key, we have to distinguish between multicast
 438          * (including broadcast) and unicast frames, the latter can only
 439          * use PTKs and STKs while the former always use GTKs. Unless, of
 440          * course, actual WEP keys ("pre-RSNA") are used, then unicast
 441          * frames can also use key indizes like GTKs. Hence, if we don't
 442          * have a PTK/STK we check the key index for a WEP key.
 443          *
 444          * Note that in a regular BSS, multicast frames are sent by the
 445          * AP only, associated stations unicast the frame to the AP first
 446          * which then multicasts it on their behalf.
 447          *
 448          * There is also a slight problem in IBSS mode: GTKs are negotiated
 449          * with each station, that is something we don't currently handle.
 450          * The spec seems to expect that one negotiates the same key with
 451          * every station but there's no such requirement; VLANs could be
 452          * possible.
 453          */
 454
 455         if (!(rx->fc & IEEE80211_FCTL_PROTECTED))
 456                 return TXRX_CONTINUE;
 457
 458         /*
 459          * No point in finding a key and decrypting if the frame is neither
 460          * addressed to us nor a multicast frame.
 461          */
 462         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 463                 return TXRX_CONTINUE;
 464
 465         if (rx->sta)
 466                 stakey = rcu_dereference(rx->sta->key);
 467
 468         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
 469                 rx->key = stakey;
 470         } else {
 471                 /*
 472                  * The device doesn't give us the IV so we won't be
 473                  * able to look up the key. That's ok though, we
 474                  * don't need to decrypt the frame, we just won't
 475                  * be able to keep statistics accurate.
 476                  * Except for key threshold notifications, should
 477                  * we somehow allow the driver to tell us which key
 478                  * the hardware used if this flag is set?
 479                  */
 480                 if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) &&
 481                     (rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED))
 482                         return TXRX_CONTINUE;
 483
 484                 hdrlen = ieee80211_get_hdrlen(rx->fc);
 485
 486                 if (rx->skb->len < 8 + hdrlen)
 487                         return TXRX_DROP; /* TODO: count this? */
 488
 489                 /*
 490                  * no need to call ieee80211_wep_get_keyidx,
 491                  * it verifies a bunch of things we've done already
 492                  */
 493                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
 494
 495                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
 496
 497                 /*
 498                  * RSNA-protected unicast frames should always be sent with
 499                  * pairwise or station-to-station keys, but for WEP we allow
 500                  * using a key index as well.
 501                  */
 502                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
 503                     !is_multicast_ether_addr(hdr->addr1))
 504                         rx->key = NULL;
 505         }
 506
 507         if (rx->key) {
 508                 rx->key->tx_rx_count++;
 509                 /* TODO: add threshold stuff again */
 510         } else {
 511                 if (net_ratelimit())
 512                         printk(KERN_DEBUG "%s: RX protected frame,"
 513                                " but have no key\n", rx->dev->name);
 514                 return TXRX_DROP;
 515         }
 516
 517         /* Check for weak IVs if possible */
 518         if (rx->sta && rx->key->conf.alg == ALG_WEP &&
 519             ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) &&
 520             (!(rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED) ||
 521              !(rx->u.rx.status->flag & RX_FLAG_DECRYPTED)) &&
 522             ieee80211_wep_is_weak_iv(rx->skb, rx->key))
 523                 rx->sta->wep_weak_iv_count++;
 524
 525         switch (rx->key->conf.alg) {
 526         case ALG_WEP:
 527                 return ieee80211_crypto_wep_decrypt(rx);
 528         case ALG_TKIP:
 529                 return ieee80211_crypto_tkip_decrypt(rx);
 530         case ALG_CCMP:
 531                 return ieee80211_crypto_ccmp_decrypt(rx);
 532         case ALG_NONE:
 533                 WARN_ON(1);
 534                 return TXRX_CONTINUE;
 535         }
 536
 537         /* not reached */
 538         WARN_ON(1);
 539         return TXRX_DROP;
 540 }
 541
 542 static void ap_sta_ps_start(struct net_device *dev, struct sta_info *sta)
 543 {
 544         struct ieee80211_sub_if_data *sdata;
 545         DECLARE_MAC_BUF(mac);
 546
 547         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 548
 549         if (sdata->bss)
 550                 atomic_inc(&sdata->bss->num_sta_ps);
 551         sta->flags |= WLAN_STA_PS;
 552         sta->pspoll = 0;
 553 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 554         printk(KERN_DEBUG "%s: STA %s aid %d enters power save mode\n",
 555                dev->name, print_mac(mac, sta->addr), sta->aid);
 556 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 557 }
 558
 559 static int ap_sta_ps_end(struct net_device *dev, struct sta_info *sta)
 560 {
 561         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 562         struct sk_buff *skb;
 563         int sent = 0;
 564         struct ieee80211_sub_if_data *sdata;
 565         struct ieee80211_tx_packet_data *pkt_data;
 566         DECLARE_MAC_BUF(mac);
 567
 568         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 569         if (sdata->bss)
 570                 atomic_dec(&sdata->bss->num_sta_ps);
 571         sta->flags &= ~(WLAN_STA_PS | WLAN_STA_TIM);
 572         sta->pspoll = 0;
 573         if (!skb_queue_empty(&sta->ps_tx_buf)) {
 574                 if (local->ops->set_tim)
 575                         local->ops->set_tim(local_to_hw(local), sta->aid, 0);
 576                 if (sdata->bss)
 577                         bss_tim_clear(local, sdata->bss, sta->aid);
 578         }
 579 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 580         printk(KERN_DEBUG "%s: STA %s aid %d exits power save mode\n",
 581                dev->name, print_mac(mac, sta->addr), sta->aid);
 582 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 583         /* Send all buffered frames to the station */
 584         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
 585                 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 586                 sent++;
 587                 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
 588                 dev_queue_xmit(skb);
 589         }
 590         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
 591                 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 592                 local->total_ps_buffered--;
 593                 sent++;
 594 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 595                 printk(KERN_DEBUG "%s: STA %s aid %d send PS frame "
 596                        "since STA not sleeping anymore\n", dev->name,
 597                        print_mac(mac, sta->addr), sta->aid);
 598 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 599                 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
 600                 dev_queue_xmit(skb);
 601         }
 602
 603         return sent;
 604 }
 605
 606 static ieee80211_txrx_result
 607 ieee80211_rx_h_sta_process(struct ieee80211_txrx_data *rx)
 608 {
 609         struct sta_info *sta = rx->sta;
 610         struct net_device *dev = rx->dev;
 611         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 612
 613         if (!sta)
 614                 return TXRX_CONTINUE;
 615
 616         /* Update last_rx only for IBSS packets which are for the current
 617          * BSSID to avoid keeping the current IBSS network alive in cases where
 618          * other STAs are using different BSSID. */
 619         if (rx->sdata->type == IEEE80211_IF_TYPE_IBSS) {
 620                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len);
 621                 if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0)
 622                         sta->last_rx = jiffies;
 623         } else
 624         if (!is_multicast_ether_addr(hdr->addr1) ||
 625             rx->sdata->type == IEEE80211_IF_TYPE_STA) {
 626                 /* Update last_rx only for unicast frames in order to prevent
 627                  * the Probe Request frames (the only broadcast frames from a
 628                  * STA in infrastructure mode) from keeping a connection alive.
 629                  */
 630                 sta->last_rx = jiffies;
 631         }
 632
 633         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 634                 return TXRX_CONTINUE;
 635
 636         sta->rx_fragments++;
 637         sta->rx_bytes += rx->skb->len;
 638         sta->last_rssi = rx->u.rx.status->ssi;
 639         sta->last_signal = rx->u.rx.status->signal;
 640         sta->last_noise = rx->u.rx.status->noise;
 641
 642         if (!(rx->fc & IEEE80211_FCTL_MOREFRAGS)) {
 643                 /* Change STA power saving mode only in the end of a frame
 644                  * exchange sequence */
 645                 if ((sta->flags & WLAN_STA_PS) && !(rx->fc & IEEE80211_FCTL_PM))
 646                         rx->u.rx.sent_ps_buffered += ap_sta_ps_end(dev, sta);
 647                 else if (!(sta->flags & WLAN_STA_PS) &&
 648                          (rx->fc & IEEE80211_FCTL_PM))
 649                         ap_sta_ps_start(dev, sta);
 650         }
 651
 652         /* Drop data::nullfunc frames silently, since they are used only to
 653          * control station power saving mode. */
 654         if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 655             (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_NULLFUNC) {
 656                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
 657                 /* Update counter and free packet here to avoid counting this
 658                  * as a dropped packed. */
 659                 sta->rx_packets++;
 660                 dev_kfree_skb(rx->skb);
 661                 return TXRX_QUEUED;
 662         }
 663
 664         return TXRX_CONTINUE;
 665 } /* ieee80211_rx_h_sta_process */
 666
 667 static inline struct ieee80211_fragment_entry *
 668 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
 669                          unsigned int frag, unsigned int seq, int rx_queue,
 670                          struct sk_buff **skb)
 671 {
 672         struct ieee80211_fragment_entry *entry;
 673         int idx;
 674
 675         idx = sdata->fragment_next;
 676         entry = &sdata->fragments[sdata->fragment_next++];
 677         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
 678                 sdata->fragment_next = 0;
 679
 680         if (!skb_queue_empty(&entry->skb_list)) {
 681 #ifdef CONFIG_MAC80211_DEBUG
 682                 struct ieee80211_hdr *hdr =
 683                         (struct ieee80211_hdr *) entry->skb_list.next->data;
 684                 DECLARE_MAC_BUF(mac);
 685                 DECLARE_MAC_BUF(mac2);
 686                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
 687                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
 688                        "addr1=%s addr2=%s\n",
 689                        sdata->dev->name, idx,
 690                        jiffies - entry->first_frag_time, entry->seq,
 691                        entry->last_frag, print_mac(mac, hdr->addr1),
 692                        print_mac(mac2, hdr->addr2));
 693 #endif /* CONFIG_MAC80211_DEBUG */
 694                 __skb_queue_purge(&entry->skb_list);
 695         }
 696
 697         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
 698         *skb = NULL;
 699         entry->first_frag_time = jiffies;
 700         entry->seq = seq;
 701         entry->rx_queue = rx_queue;
 702         entry->last_frag = frag;
 703         entry->ccmp = 0;
 704         entry->extra_len = 0;
 705
 706         return entry;
 707 }
 708
 709 static inline struct ieee80211_fragment_entry *
 710 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
 711                           u16 fc, unsigned int frag, unsigned int seq,
 712                           int rx_queue, struct ieee80211_hdr *hdr)
 713 {
 714         struct ieee80211_fragment_entry *entry;
 715         int i, idx;
 716
 717         idx = sdata->fragment_next;
 718         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
 719                 struct ieee80211_hdr *f_hdr;
 720                 u16 f_fc;
 721
 722                 idx--;
 723                 if (idx < 0)
 724                         idx = IEEE80211_FRAGMENT_MAX - 1;
 725
 726                 entry = &sdata->fragments[idx];
 727                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
 728                     entry->rx_queue != rx_queue ||
 729                     entry->last_frag + 1 != frag)
 730                         continue;
 731
 732                 f_hdr = (struct ieee80211_hdr *) entry->skb_list.next->data;
 733                 f_fc = le16_to_cpu(f_hdr->frame_control);
 734
 735                 if ((fc & IEEE80211_FCTL_FTYPE) != (f_fc & IEEE80211_FCTL_FTYPE) ||
 736                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
 737                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
 738                         continue;
 739
 740                 if (entry->first_frag_time + 2 * HZ < jiffies) {
 741                         __skb_queue_purge(&entry->skb_list);
 742                         continue;
 743                 }
 744                 return entry;
 745         }
 746
 747         return NULL;
 748 }
 749
 750 static ieee80211_txrx_result
 751 ieee80211_rx_h_defragment(struct ieee80211_txrx_data *rx)
 752 {
 753         struct ieee80211_hdr *hdr;
 754         u16 sc;
 755         unsigned int frag, seq;
 756         struct ieee80211_fragment_entry *entry;
 757         struct sk_buff *skb;
 758         DECLARE_MAC_BUF(mac);
 759
 760         hdr = (struct ieee80211_hdr *) rx->skb->data;
 761         sc = le16_to_cpu(hdr->seq_ctrl);
 762         frag = sc & IEEE80211_SCTL_FRAG;
 763
 764         if (likely((!(rx->fc & IEEE80211_FCTL_MOREFRAGS) && frag == 0) ||
 765                    (rx->skb)->len < 24 ||
 766                    is_multicast_ether_addr(hdr->addr1))) {
 767                 /* not fragmented */
 768                 goto out;
 769         }
 770         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
 771
 772         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
 773
 774         if (frag == 0) {
 775                 /* This is the first fragment of a new frame. */
 776                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
 777                                                  rx->u.rx.queue, &(rx->skb));
 778                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
 779                     (rx->fc & IEEE80211_FCTL_PROTECTED)) {
 780                         /* Store CCMP PN so that we can verify that the next
 781                          * fragment has a sequential PN value. */
 782                         entry->ccmp = 1;
 783                         memcpy(entry->last_pn,
 784                                rx->key->u.ccmp.rx_pn[rx->u.rx.queue],
 785                                CCMP_PN_LEN);
 786                 }
 787                 return TXRX_QUEUED;
 788         }
 789
 790         /* This is a fragment for a frame that should already be pending in
 791          * fragment cache. Add this fragment to the end of the pending entry.
 792          */
 793         entry = ieee80211_reassemble_find(rx->sdata, rx->fc, frag, seq,
 794                                           rx->u.rx.queue, hdr);
 795         if (!entry) {
 796                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 797                 return TXRX_DROP;
 798         }
 799
 800         /* Verify that MPDUs within one MSDU have sequential PN values.
 801          * (IEEE 802.11i, 8.3.3.4.5) */
 802         if (entry->ccmp) {
 803                 int i;
 804                 u8 pn[CCMP_PN_LEN], *rpn;
 805                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
 806                         return TXRX_DROP;
 807                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
 808                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
 809                         pn[i]++;
 810                         if (pn[i])
 811                                 break;
 812                 }
 813                 rpn = rx->key->u.ccmp.rx_pn[rx->u.rx.queue];
 814                 if (memcmp(pn, rpn, CCMP_PN_LEN) != 0) {
 815                         if (net_ratelimit())
 816                                 printk(KERN_DEBUG "%s: defrag: CCMP PN not "
 817                                        "sequential A2=%s"
 818                                        " PN=%02x%02x%02x%02x%02x%02x "
 819                                        "(expected %02x%02x%02x%02x%02x%02x)\n",
 820                                        rx->dev->name, print_mac(mac, hdr->addr2),
 821                                        rpn[0], rpn[1], rpn[2], rpn[3], rpn[4],
 822                                        rpn[5], pn[0], pn[1], pn[2], pn[3],
 823                                        pn[4], pn[5]);
 824                         return TXRX_DROP;
 825                 }
 826                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
 827         }
 828
 829         skb_pull(rx->skb, ieee80211_get_hdrlen(rx->fc));
 830         __skb_queue_tail(&entry->skb_list, rx->skb);
 831         entry->last_frag = frag;
 832         entry->extra_len += rx->skb->len;
 833         if (rx->fc & IEEE80211_FCTL_MOREFRAGS) {
 834                 rx->skb = NULL;
 835                 return TXRX_QUEUED;
 836         }
 837
 838         rx->skb = __skb_dequeue(&entry->skb_list);
 839         if (skb_tailroom(rx->skb) < entry->extra_len) {
 840                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
 841                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
 842                                               GFP_ATOMIC))) {
 843                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 844                         __skb_queue_purge(&entry->skb_list);
 845                         return TXRX_DROP;
 846                 }
 847         }
 848         while ((skb = __skb_dequeue(&entry->skb_list))) {
 849                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
 850                 dev_kfree_skb(skb);
 851         }
 852
 853         /* Complete frame has been reassembled - process it now */
 854         rx->flags |= IEEE80211_TXRXD_FRAGMENTED;
 855
 856  out:
 857         if (rx->sta)
 858                 rx->sta->rx_packets++;
 859         if (is_multicast_ether_addr(hdr->addr1))
 860                 rx->local->dot11MulticastReceivedFrameCount++;
 861         else
 862                 ieee80211_led_rx(rx->local);
 863         return TXRX_CONTINUE;
 864 }
 865
 866 static ieee80211_txrx_result
 867 ieee80211_rx_h_ps_poll(struct ieee80211_txrx_data *rx)
 868 {
 869         struct sk_buff *skb;
 870         int no_pending_pkts;
 871         DECLARE_MAC_BUF(mac);
 872
 873         if (likely(!rx->sta ||
 874                    (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL ||
 875                    (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PSPOLL ||
 876                    !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)))
 877                 return TXRX_CONTINUE;
 878
 879         skb = skb_dequeue(&rx->sta->tx_filtered);
 880         if (!skb) {
 881                 skb = skb_dequeue(&rx->sta->ps_tx_buf);
 882                 if (skb)
 883                         rx->local->total_ps_buffered--;
 884         }
 885         no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
 886                 skb_queue_empty(&rx->sta->ps_tx_buf);
 887
 888         if (skb) {
 889                 struct ieee80211_hdr *hdr =
 890                         (struct ieee80211_hdr *) skb->data;
 891
 892                 /* tell TX path to send one frame even though the STA may
 893                  * still remain is PS mode after this frame exchange */
 894                 rx->sta->pspoll = 1;
 895
 896 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 897                 printk(KERN_DEBUG "STA %s aid %d: PS Poll (entries after %d)\n",
 898                        print_mac(mac, rx->sta->addr), rx->sta->aid,
 899                        skb_queue_len(&rx->sta->ps_tx_buf));
 900 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 901
 902                 /* Use MoreData flag to indicate whether there are more
 903                  * buffered frames for this STA */
 904                 if (no_pending_pkts) {
 905                         hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
 906                         rx->sta->flags &= ~WLAN_STA_TIM;
 907                 } else
 908                         hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
 909
 910                 dev_queue_xmit(skb);
 911
 912                 if (no_pending_pkts) {
 913                         if (rx->local->ops->set_tim)
 914                                 rx->local->ops->set_tim(local_to_hw(rx->local),
 915                                                        rx->sta->aid, 0);
 916                         if (rx->sdata->bss)
 917                                 bss_tim_clear(rx->local, rx->sdata->bss, rx->sta->aid);
 918                 }
 919 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 920         } else if (!rx->u.rx.sent_ps_buffered) {
 921                 printk(KERN_DEBUG "%s: STA %s sent PS Poll even "
 922                        "though there is no buffered frames for it\n",
 923                        rx->dev->name, print_mac(mac, rx->sta->addr));
 924 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 925
 926         }
 927
 928         /* Free PS Poll skb here instead of returning TXRX_DROP that would
 929          * count as an dropped frame. */
 930         dev_kfree_skb(rx->skb);
 931
 932         return TXRX_QUEUED;
 933 }
 934
 935 static ieee80211_txrx_result
 936 ieee80211_rx_h_remove_qos_control(struct ieee80211_txrx_data *rx)
 937 {
 938         u16 fc = rx->fc;
 939         u8 *data = rx->skb->data;
 940         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) data;
 941
 942         if (!WLAN_FC_IS_QOS_DATA(fc))
 943                 return TXRX_CONTINUE;
 944
 945         /* remove the qos control field, update frame type and meta-data */
 946         memmove(data + 2, data, ieee80211_get_hdrlen(fc) - 2);
 947         hdr = (struct ieee80211_hdr *) skb_pull(rx->skb, 2);
 948         /* change frame type to non QOS */
 949         rx->fc = fc &= ~IEEE80211_STYPE_QOS_DATA;
 950         hdr->frame_control = cpu_to_le16(fc);
 951
 952         return TXRX_CONTINUE;
 953 }
 954
 955 static ieee80211_txrx_result
 956 ieee80211_rx_h_802_1x_pae(struct ieee80211_txrx_data *rx)
 957 {
 958         if (rx->sdata->eapol && ieee80211_is_eapol(rx->skb) &&
 959             rx->sdata->type != IEEE80211_IF_TYPE_STA &&
 960             (rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 961                 return TXRX_CONTINUE;
 962
 963         if (unlikely(rx->sdata->ieee802_1x &&
 964                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 965                      (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
 966                      (!rx->sta || !(rx->sta->flags & WLAN_STA_AUTHORIZED)) &&
 967                      !ieee80211_is_eapol(rx->skb))) {
 968 #ifdef CONFIG_MAC80211_DEBUG
 969                 struct ieee80211_hdr *hdr =
 970                         (struct ieee80211_hdr *) rx->skb->data;
 971                 DECLARE_MAC_BUF(mac);
 972                 printk(KERN_DEBUG "%s: dropped frame from %s"
 973                        " (unauthorized port)\n", rx->dev->name,
 974                        print_mac(mac, hdr->addr2));
 975 #endif /* CONFIG_MAC80211_DEBUG */
 976                 return TXRX_DROP;
 977         }
 978
 979         return TXRX_CONTINUE;
 980 }
 981
 982 static ieee80211_txrx_result
 983 ieee80211_rx_h_drop_unencrypted(struct ieee80211_txrx_data *rx)
 984 {
 985         /*
 986          * Pass through unencrypted frames if the hardware has
 987          * decrypted them already.
 988          */
 989         if (rx->u.rx.status->flag & RX_FLAG_DECRYPTED)
 990                 return TXRX_CONTINUE;
 991
 992         /* Drop unencrypted frames if key is set. */
 993         if (unlikely(!(rx->fc & IEEE80211_FCTL_PROTECTED) &&
 994                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 995                      (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
 996                      (rx->key || rx->sdata->drop_unencrypted) &&
 997                      (rx->sdata->eapol == 0 ||
 998                       !ieee80211_is_eapol(rx->skb)))) {
 999                 if (net_ratelimit())
1000                         printk(KERN_DEBUG "%s: RX non-WEP frame, but expected "
1001                                "encryption\n", rx->dev->name);
1002                 return TXRX_DROP;
1003         }
1004         return TXRX_CONTINUE;
1005 }
1006
1007 static ieee80211_txrx_result
1008 ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
1009 {
1010         struct net_device *dev = rx->dev;
1011         struct ieee80211_local *local = rx->local;
1012         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
1013         u16 fc, hdrlen, ethertype;
1014         u8 *payload;
1015         u8 dst[ETH_ALEN];
1016         u8 src[ETH_ALEN];
1017         struct sk_buff *skb = rx->skb, *skb2;
1018         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1019         DECLARE_MAC_BUF(mac);
1020         DECLARE_MAC_BUF(mac2);
1021         DECLARE_MAC_BUF(mac3);
1022         DECLARE_MAC_BUF(mac4);
1023
1024         fc = rx->fc;
1025         if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
1026                 return TXRX_CONTINUE;
1027
1028         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1029                 return TXRX_DROP;
1030
1031         hdrlen = ieee80211_get_hdrlen(fc);
1032
1033         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
1034          * header
1035          * IEEE 802.11 address fields:
1036          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
1037          *   0     0   DA    SA    BSSID n/a
1038          *   0     1   DA    BSSID SA    n/a
1039          *   1     0   BSSID SA    DA    n/a
1040          *   1     1   RA    TA    DA    SA
1041          */
1042
1043         switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
1044         case IEEE80211_FCTL_TODS:
1045                 /* BSSID SA DA */
1046                 memcpy(dst, hdr->addr3, ETH_ALEN);
1047                 memcpy(src, hdr->addr2, ETH_ALEN);
1048
1049                 if (unlikely(sdata->type != IEEE80211_IF_TYPE_AP &&
1050                              sdata->type != IEEE80211_IF_TYPE_VLAN)) {
1051                         if (net_ratelimit())
1052                                 printk(KERN_DEBUG "%s: dropped ToDS frame "
1053                                        "(BSSID=%s SA=%s DA=%s)\n",
1054                                        dev->name,
1055                                        print_mac(mac, hdr->addr1),
1056                                        print_mac(mac2, hdr->addr2),
1057                                        print_mac(mac3, hdr->addr3));
1058                         return TXRX_DROP;
1059                 }
1060                 break;
1061         case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
1062                 /* RA TA DA SA */
1063                 memcpy(dst, hdr->addr3, ETH_ALEN);
1064                 memcpy(src, hdr->addr4, ETH_ALEN);
1065
1066                 if (unlikely(sdata->type != IEEE80211_IF_TYPE_WDS)) {
1067                         if (net_ratelimit())
1068                                 printk(KERN_DEBUG "%s: dropped FromDS&ToDS "
1069                                        "frame (RA=%s TA=%s DA=%s SA=%s)\n",
1070                                        rx->dev->name,
1071                                        print_mac(mac, hdr->addr1),
1072                                        print_mac(mac2, hdr->addr2),
1073                                        print_mac(mac3, hdr->addr3),
1074                                        print_mac(mac4, hdr->addr4));
1075                         return TXRX_DROP;
1076                 }
1077                 break;
1078         case IEEE80211_FCTL_FROMDS:
1079                 /* DA BSSID SA */
1080                 memcpy(dst, hdr->addr1, ETH_ALEN);
1081                 memcpy(src, hdr->addr3, ETH_ALEN);
1082
1083                 if (sdata->type != IEEE80211_IF_TYPE_STA ||
1084                     (is_multicast_ether_addr(dst) &&
1085                      !compare_ether_addr(src, dev->dev_addr)))
1086                         return TXRX_DROP;
1087                 break;
1088         case 0:
1089                 /* DA SA BSSID */
1090                 memcpy(dst, hdr->addr1, ETH_ALEN);
1091                 memcpy(src, hdr->addr2, ETH_ALEN);
1092
1093                 if (sdata->type != IEEE80211_IF_TYPE_IBSS) {
1094                         if (net_ratelimit()) {
1095                                 printk(KERN_DEBUG "%s: dropped IBSS frame "
1096                                        "(DA=%s SA=%s BSSID=%s)\n",
1097                                        dev->name,
1098                                        print_mac(mac, hdr->addr1),
1099                                        print_mac(mac2, hdr->addr2),
1100                                        print_mac(mac3, hdr->addr3));
1101                         }
1102                         return TXRX_DROP;
1103                 }
1104                 break;
1105         }
1106
1107         payload = skb->data + hdrlen;
1108
1109         if (unlikely(skb->len - hdrlen < 8)) {
1110                 if (net_ratelimit()) {
1111                         printk(KERN_DEBUG "%s: RX too short data frame "
1112                                "payload\n", dev->name);
1113                 }
1114                 return TXRX_DROP;
1115         }
1116
1117         ethertype = (payload[6] << 8) | payload[7];
1118
1119         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1120                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1121                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1122                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1123                  * replace EtherType */
1124                 skb_pull(skb, hdrlen + 6);
1125                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1126                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1127         } else {
1128                 struct ethhdr *ehdr;
1129                 __be16 len;
1130                 skb_pull(skb, hdrlen);
1131                 len = htons(skb->len);
1132                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1133                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1134                 memcpy(ehdr->h_source, src, ETH_ALEN);
1135                 ehdr->h_proto = len;
1136         }
1137         skb->dev = dev;
1138
1139         skb2 = NULL;
1140
1141         dev->stats.rx_packets++;
1142         dev->stats.rx_bytes += skb->len;
1143
1144         if (local->bridge_packets && (sdata->type == IEEE80211_IF_TYPE_AP
1145             || sdata->type == IEEE80211_IF_TYPE_VLAN) &&
1146             (rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
1147                 if (is_multicast_ether_addr(skb->data)) {
1148                         /* send multicast frames both to higher layers in
1149                          * local net stack and back to the wireless media */
1150                         skb2 = skb_copy(skb, GFP_ATOMIC);
1151                         if (!skb2 && net_ratelimit())
1152                                 printk(KERN_DEBUG "%s: failed to clone "
1153                                        "multicast frame\n", dev->name);
1154                 } else {
1155                         struct sta_info *dsta;
1156                         dsta = sta_info_get(local, skb->data);
1157                         if (dsta && !dsta->dev) {
1158                                 if (net_ratelimit())
1159                                         printk(KERN_DEBUG "Station with null "
1160                                                "dev structure!\n");
1161                         } else if (dsta && dsta->dev == dev) {
1162                                 /* Destination station is associated to this
1163                                  * AP, so send the frame directly to it and
1164                                  * do not pass the frame to local net stack.
1165                                  */
1166                                 skb2 = skb;
1167                                 skb = NULL;
1168                         }
1169                         if (dsta)
1170                                 sta_info_put(dsta);
1171                 }
1172         }
1173
1174         if (skb) {
1175                 /* deliver to local stack */
1176                 skb->protocol = eth_type_trans(skb, dev);
1177                 memset(skb->cb, 0, sizeof(skb->cb));
1178                 netif_rx(skb);
1179         }
1180
1181         if (skb2) {
1182                 /* send to wireless media */
1183                 skb2->protocol = __constant_htons(ETH_P_802_3);
1184                 skb_set_network_header(skb2, 0);
1185                 skb_set_mac_header(skb2, 0);
1186                 dev_queue_xmit(skb2);
1187         }
1188
1189         return TXRX_QUEUED;
1190 }
1191
1192 static ieee80211_txrx_result
1193 ieee80211_rx_h_mgmt(struct ieee80211_txrx_data *rx)
1194 {
1195         struct ieee80211_sub_if_data *sdata;
1196
1197         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
1198                 return TXRX_DROP;
1199
1200         sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1201         if ((sdata->type == IEEE80211_IF_TYPE_STA ||
1202              sdata->type == IEEE80211_IF_TYPE_IBSS) &&
1203             !rx->local->user_space_mlme)
1204                 ieee80211_sta_rx_mgmt(rx->dev, rx->skb, rx->u.rx.status);
1205         else
1206                 return TXRX_DROP;
1207
1208         return TXRX_QUEUED;
1209 }
1210
1211 static inline ieee80211_txrx_result __ieee80211_invoke_rx_handlers(
1212                                 struct ieee80211_local *local,
1213                                 ieee80211_rx_handler *handlers,
1214                                 struct ieee80211_txrx_data *rx,
1215                                 struct sta_info *sta)
1216 {
1217         ieee80211_rx_handler *handler;
1218         ieee80211_txrx_result res = TXRX_DROP;
1219
1220         for (handler = handlers; *handler != NULL; handler++) {
1221                 res = (*handler)(rx);
1222
1223                 switch (res) {
1224                 case TXRX_CONTINUE:
1225                         continue;
1226                 case TXRX_DROP:
1227                         I802_DEBUG_INC(local->rx_handlers_drop);
1228                         if (sta)
1229                                 sta->rx_dropped++;
1230                         break;
1231                 case TXRX_QUEUED:
1232                         I802_DEBUG_INC(local->rx_handlers_queued);
1233                         break;
1234                 }
1235                 break;
1236         }
1237
1238         if (res == TXRX_DROP)
1239                 dev_kfree_skb(rx->skb);
1240         return res;
1241 }
1242
1243 static inline void ieee80211_invoke_rx_handlers(struct ieee80211_local *local,
1244                                                 ieee80211_rx_handler *handlers,
1245                                                 struct ieee80211_txrx_data *rx,
1246                                                 struct sta_info *sta)
1247 {
1248         if (__ieee80211_invoke_rx_handlers(local, handlers, rx, sta) ==
1249             TXRX_CONTINUE)
1250                 dev_kfree_skb(rx->skb);
1251 }
1252
1253 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1254                                             struct ieee80211_hdr *hdr,
1255                                             struct sta_info *sta,
1256                                             struct ieee80211_txrx_data *rx)
1257 {
1258         int keyidx, hdrlen;
1259         DECLARE_MAC_BUF(mac);
1260         DECLARE_MAC_BUF(mac2);
1261
1262         hdrlen = ieee80211_get_hdrlen_from_skb(rx->skb);
1263         if (rx->skb->len >= hdrlen + 4)
1264                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1265         else
1266                 keyidx = -1;
1267
1268         if (net_ratelimit())
1269                 printk(KERN_DEBUG "%s: TKIP hwaccel reported Michael MIC "
1270                        "failure from %s to %s keyidx=%d\n",
1271                        dev->name, print_mac(mac, hdr->addr2),
1272                        print_mac(mac2, hdr->addr1), keyidx);
1273
1274         if (!sta) {
1275                 /*
1276                  * Some hardware seem to generate incorrect Michael MIC
1277                  * reports; ignore them to avoid triggering countermeasures.
1278                  */
1279                 if (net_ratelimit())
1280                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1281                                "error for unknown address %s\n",
1282                                dev->name, print_mac(mac, hdr->addr2));
1283                 goto ignore;
1284         }
1285
1286         if (!(rx->fc & IEEE80211_FCTL_PROTECTED)) {
1287                 if (net_ratelimit())
1288                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1289                                "error for a frame with no PROTECTED flag (src "
1290                                "%s)\n", dev->name, print_mac(mac, hdr->addr2));
1291                 goto ignore;
1292         }
1293
1294         if (rx->sdata->type == IEEE80211_IF_TYPE_AP && keyidx) {
1295                 /*
1296                  * APs with pairwise keys should never receive Michael MIC
1297                  * errors for non-zero keyidx because these are reserved for
1298                  * group keys and only the AP is sending real multicast
1299                  * frames in the BSS.
1300                  */
1301                 if (net_ratelimit())
1302                         printk(KERN_DEBUG "%s: ignored Michael MIC error for "
1303                                "a frame with non-zero keyidx (%d)"
1304                                " (src %s)\n", dev->name, keyidx,
1305                                print_mac(mac, hdr->addr2));
1306                 goto ignore;
1307         }
1308
1309         if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
1310             ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
1311              (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)) {
1312                 if (net_ratelimit())
1313                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1314                                "error for a frame that cannot be encrypted "
1315                                "(fc=0x%04x) (src %s)\n",
1316                                dev->name, rx->fc, print_mac(mac, hdr->addr2));
1317                 goto ignore;
1318         }
1319
1320         mac80211_ev_michael_mic_failure(rx->dev, keyidx, hdr);
1321  ignore:
1322         dev_kfree_skb(rx->skb);
1323         rx->skb = NULL;
1324 }
1325
1326 ieee80211_rx_handler ieee80211_rx_handlers[] =
1327 {
1328         ieee80211_rx_h_if_stats,
1329         ieee80211_rx_h_passive_scan,
1330         ieee80211_rx_h_check,
1331         ieee80211_rx_h_decrypt,
1332         ieee80211_rx_h_sta_process,
1333         ieee80211_rx_h_defragment,
1334         ieee80211_rx_h_ps_poll,
1335         ieee80211_rx_h_michael_mic_verify,
1336         /* this must be after decryption - so header is counted in MPDU mic
1337          * must be before pae and data, so QOS_DATA format frames
1338          * are not passed to user space by these functions
1339          */
1340         ieee80211_rx_h_remove_qos_control,
1341         ieee80211_rx_h_802_1x_pae,
1342         ieee80211_rx_h_drop_unencrypted,
1343         ieee80211_rx_h_data,
1344         ieee80211_rx_h_mgmt,
1345         NULL
1346 };
1347
1348 /* main receive path */
1349
1350 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
1351                                 u8 *bssid, struct ieee80211_txrx_data *rx,
1352                                 struct ieee80211_hdr *hdr)
1353 {
1354         int multicast = is_multicast_ether_addr(hdr->addr1);
1355
1356         switch (sdata->type) {
1357         case IEEE80211_IF_TYPE_STA:
1358                 if (!bssid)
1359                         return 0;
1360                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1361                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1362                                 return 0;
1363                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1364                 } else if (!multicast &&
1365                            compare_ether_addr(sdata->dev->dev_addr,
1366                                               hdr->addr1) != 0) {
1367                         if (!(sdata->dev->flags & IFF_PROMISC))
1368                                 return 0;
1369                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1370                 }
1371                 break;
1372         case IEEE80211_IF_TYPE_IBSS:
1373                 if (!bssid)
1374                         return 0;
1375                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1376                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1377                                 return 0;
1378                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1379                 } else if (!multicast &&
1380                            compare_ether_addr(sdata->dev->dev_addr,
1381                                               hdr->addr1) != 0) {
1382                         if (!(sdata->dev->flags & IFF_PROMISC))
1383                                 return 0;
1384                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1385                 } else if (!rx->sta)
1386                         rx->sta = ieee80211_ibss_add_sta(sdata->dev, rx->skb,
1387                                                          bssid, hdr->addr2);
1388                 break;
1389         case IEEE80211_IF_TYPE_VLAN:
1390         case IEEE80211_IF_TYPE_AP:
1391                 if (!bssid) {
1392                         if (compare_ether_addr(sdata->dev->dev_addr,
1393                                                hdr->addr1))
1394                                 return 0;
1395                 } else if (!ieee80211_bssid_match(bssid,
1396                                         sdata->dev->dev_addr)) {
1397                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1398                                 return 0;
1399                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1400                 }
1401                 if (sdata->dev == sdata->local->mdev &&
1402                     !(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1403                         /* do not receive anything via
1404                          * master device when not scanning */
1405                         return 0;
1406                 break;
1407         case IEEE80211_IF_TYPE_WDS:
1408                 if (bssid ||
1409                     (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
1410                         return 0;
1411                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
1412                         return 0;
1413                 break;
1414         case IEEE80211_IF_TYPE_MNTR:
1415                 /* take everything */
1416                 break;
1417         case IEEE80211_IF_TYPE_INVALID:
1418                 /* should never get here */
1419                 WARN_ON(1);
1420                 break;
1421         }
1422
1423         return 1;
1424 }
1425
1426 /*
1427  * This is the receive path handler. It is called by a low level driver when an
1428  * 802.11 MPDU is received from the hardware.
1429  */
1430 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
1431                     struct ieee80211_rx_status *status)
1432 {
1433         struct ieee80211_local *local = hw_to_local(hw);
1434         struct ieee80211_sub_if_data *sdata;
1435         struct sta_info *sta;
1436         struct ieee80211_hdr *hdr;
1437         struct ieee80211_txrx_data rx;
1438         u16 type;
1439         int prepres;
1440         struct ieee80211_sub_if_data *prev = NULL;
1441         struct sk_buff *skb_new;
1442         u8 *bssid;
1443
1444         /*
1445          * key references and virtual interfaces are protected using RCU
1446          * and this requires that we are in a read-side RCU section during
1447          * receive processing
1448          */
1449         rcu_read_lock();
1450
1451         /*
1452          * Frames with failed FCS/PLCP checksum are not returned,
1453          * all other frames are returned without radiotap header
1454          * if it was previously present.
1455          * Also, frames with less than 16 bytes are dropped.
1456          */
1457         skb = ieee80211_rx_monitor(local, skb, status);
1458         if (!skb) {
1459                 rcu_read_unlock();
1460                 return;
1461         }
1462
1463         hdr = (struct ieee80211_hdr *) skb->data;
1464         memset(&rx, 0, sizeof(rx));
1465         rx.skb = skb;
1466         rx.local = local;
1467
1468         rx.u.rx.status = status;
1469         rx.fc = le16_to_cpu(hdr->frame_control);
1470         type = rx.fc & IEEE80211_FCTL_FTYPE;
1471
1472         if (type == IEEE80211_FTYPE_DATA || type == IEEE80211_FTYPE_MGMT)
1473                 local->dot11ReceivedFragmentCount++;
1474
1475         sta = rx.sta = sta_info_get(local, hdr->addr2);
1476         if (sta) {
1477                 rx.dev = rx.sta->dev;
1478                 rx.sdata = IEEE80211_DEV_TO_SUB_IF(rx.dev);
1479         }
1480
1481         if ((status->flag & RX_FLAG_MMIC_ERROR)) {
1482                 ieee80211_rx_michael_mic_report(local->mdev, hdr, sta, &rx);
1483                 goto end;
1484         }
1485
1486         if (unlikely(local->sta_scanning))
1487                 rx.flags |= IEEE80211_TXRXD_RXIN_SCAN;
1488
1489         if (__ieee80211_invoke_rx_handlers(local, local->rx_pre_handlers, &rx,
1490                                            sta) != TXRX_CONTINUE)
1491                 goto end;
1492         skb = rx.skb;
1493
1494         if (sta && !(sta->flags & (WLAN_STA_WDS | WLAN_STA_ASSOC_AP)) &&
1495             !atomic_read(&local->iff_promiscs) &&
1496             !is_multicast_ether_addr(hdr->addr1)) {
1497                 rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
1498                 ieee80211_invoke_rx_handlers(local, local->rx_handlers, &rx,
1499                                              rx.sta);
1500                 sta_info_put(sta);
1501                 rcu_read_unlock();
1502                 return;
1503         }
1504
1505         bssid = ieee80211_get_bssid(hdr, skb->len);
1506
1507         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1508                 if (!netif_running(sdata->dev))
1509                         continue;
1510
1511                 if (sdata->type == IEEE80211_IF_TYPE_MNTR)
1512                         continue;
1513
1514                 rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
1515                 prepres = prepare_for_handlers(sdata, bssid, &rx, hdr);
1516                 /* prepare_for_handlers can change sta */
1517                 sta = rx.sta;
1518
1519                 if (!prepres)
1520                         continue;
1521
1522                 /*
1523                  * frame is destined for this interface, but if it's not
1524                  * also for the previous one we handle that after the
1525                  * loop to avoid copying the SKB once too much
1526                  */
1527
1528                 if (!prev) {
1529                         prev = sdata;
1530                         continue;
1531                 }
1532
1533                 /*
1534                  * frame was destined for the previous interface
1535                  * so invoke RX handlers for it
1536                  */
1537
1538                 skb_new = skb_copy(skb, GFP_ATOMIC);
1539                 if (!skb_new) {
1540                         if (net_ratelimit())
1541                                 printk(KERN_DEBUG "%s: failed to copy "
1542                                        "multicast frame for %s",
1543                                        wiphy_name(local->hw.wiphy),
1544                                        prev->dev->name);
1545                         continue;
1546                 }
1547                 rx.skb = skb_new;
1548                 rx.dev = prev->dev;
1549                 rx.sdata = prev;
1550                 ieee80211_invoke_rx_handlers(local, local->rx_handlers,
1551                                              &rx, sta);
1552                 prev = sdata;
1553         }
1554         if (prev) {
1555                 rx.skb = skb;
1556                 rx.dev = prev->dev;
1557                 rx.sdata = prev;
1558                 ieee80211_invoke_rx_handlers(local, local->rx_handlers,
1559                                              &rx, sta);
1560         } else
1561                 dev_kfree_skb(skb);
1562
1563  end:
1564         rcu_read_unlock();
1565
1566         if (sta)
1567                 sta_info_put(sta);
1568 }
1569 EXPORT_SYMBOL(__ieee80211_rx);
1570
1571 /* This is a version of the rx handler that can be called from hard irq
1572  * context. Post the skb on the queue and schedule the tasklet */
1573 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
1574                           struct ieee80211_rx_status *status)
1575 {
1576         struct ieee80211_local *local = hw_to_local(hw);
1577
1578         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
1579
1580         skb->dev = local->mdev;
1581         /* copy status into skb->cb for use by tasklet */
1582         memcpy(skb->cb, status, sizeof(*status));
1583         skb->pkt_type = IEEE80211_RX_MSG;
1584         skb_queue_tail(&local->skb_queue, skb);
1585         tasklet_schedule(&local->tasklet);
1586 }
1587 EXPORT_SYMBOL(ieee80211_rx_irqsafe);