package/mac80211/src/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         ieee80211_txrx_result result = TXRX_DROP;
 428         struct ieee80211_key *stakey = NULL;
 429
 430         /*
 431          * Key selection 101
 432          *
 433          * There are three types of keys:
 434          *  - GTK (group keys)
 435          *  - PTK (pairwise keys)
 436          *  - STK (station-to-station pairwise keys)
 437          *
 438          * When selecting a key, we have to distinguish between multicast
 439          * (including broadcast) and unicast frames, the latter can only
 440          * use PTKs and STKs while the former always use GTKs. Unless, of
 441          * course, actual WEP keys ("pre-RSNA") are used, then unicast
 442          * frames can also use key indizes like GTKs. Hence, if we don't
 443          * have a PTK/STK we check the key index for a WEP key.
 444          *
 445          * Note that in a regular BSS, multicast frames are sent by the
 446          * AP only, associated stations unicast the frame to the AP first
 447          * which then multicasts it on their behalf.
 448          *
 449          * There is also a slight problem in IBSS mode: GTKs are negotiated
 450          * with each station, that is something we don't currently handle.
 451          * The spec seems to expect that one negotiates the same key with
 452          * every station but there's no such requirement; VLANs could be
 453          * possible.
 454          */
 455
 456         if (!(rx->fc & IEEE80211_FCTL_PROTECTED))
 457                 return TXRX_CONTINUE;
 458
 459         /*
 460          * No point in finding a key and decrypting if the frame is neither
 461          * addressed to us nor a multicast frame.
 462          */
 463         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 464                 return TXRX_CONTINUE;
 465
 466         if (rx->sta)
 467                 stakey = rcu_dereference(rx->sta->key);
 468
 469         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
 470                 rx->key = stakey;
 471         } else {
 472                 /*
 473                  * The device doesn't give us the IV so we won't be
 474                  * able to look up the key. That's ok though, we
 475                  * don't need to decrypt the frame, we just won't
 476                  * be able to keep statistics accurate.
 477                  * Except for key threshold notifications, should
 478                  * we somehow allow the driver to tell us which key
 479                  * the hardware used if this flag is set?
 480                  */
 481                 if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) &&
 482                     (rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED))
 483                         return TXRX_CONTINUE;
 484
 485                 hdrlen = ieee80211_get_hdrlen(rx->fc);
 486
 487                 if (rx->skb->len < 8 + hdrlen)
 488                         return TXRX_DROP; /* TODO: count this? */
 489
 490                 /*
 491                  * no need to call ieee80211_wep_get_keyidx,
 492                  * it verifies a bunch of things we've done already
 493                  */
 494                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
 495
 496                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
 497
 498                 /*
 499                  * RSNA-protected unicast frames should always be sent with
 500                  * pairwise or station-to-station keys, but for WEP we allow
 501                  * using a key index as well.
 502                  */
 503                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
 504                     !is_multicast_ether_addr(hdr->addr1))
 505                         rx->key = NULL;
 506         }
 507
 508         if (rx->key) {
 509                 rx->key->tx_rx_count++;
 510                 /* TODO: add threshold stuff again */
 511         } else {
 512                 if (net_ratelimit())
 513                         printk(KERN_DEBUG "%s: RX protected frame,"
 514                                " but have no key\n", rx->dev->name);
 515                 return TXRX_DROP;
 516         }
 517
 518         /* Check for weak IVs if possible */
 519         if (rx->sta && rx->key->conf.alg == ALG_WEP &&
 520             ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) &&
 521             (!(rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED) ||
 522              !(rx->u.rx.status->flag & RX_FLAG_DECRYPTED)) &&
 523             ieee80211_wep_is_weak_iv(rx->skb, rx->key))
 524                 rx->sta->wep_weak_iv_count++;
 525
 526         switch (rx->key->conf.alg) {
 527         case ALG_WEP:
 528                 result = ieee80211_crypto_wep_decrypt(rx);
 529                 break;
 530         case ALG_TKIP:
 531                 result = ieee80211_crypto_tkip_decrypt(rx);
 532                 break;
 533         case ALG_CCMP:
 534                 result = ieee80211_crypto_ccmp_decrypt(rx);
 535                 break;
 536         }
 537
 538         /* either the frame has been decrypted or will be dropped */
 539         rx->u.rx.status->flag |= RX_FLAG_DECRYPTED;
 540
 541         return result;
 542 }
 543
 544 static void ap_sta_ps_start(struct net_device *dev, struct sta_info *sta)
 545 {
 546         struct ieee80211_sub_if_data *sdata;
 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 " MAC_FMT " aid %d enters power "
 555                "save mode\n", dev->name, MAC_ARG(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
 567         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 568         if (sdata->bss)
 569                 atomic_dec(&sdata->bss->num_sta_ps);
 570         sta->flags &= ~(WLAN_STA_PS | WLAN_STA_TIM);
 571         sta->pspoll = 0;
 572         if (!skb_queue_empty(&sta->ps_tx_buf)) {
 573                 if (local->ops->set_tim)
 574                         local->ops->set_tim(local_to_hw(local), sta->aid, 0);
 575                 if (sdata->bss)
 576                         bss_tim_clear(local, sdata->bss, sta->aid);
 577         }
 578 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 579         printk(KERN_DEBUG "%s: STA " MAC_FMT " aid %d exits power "
 580                "save mode\n", dev->name, MAC_ARG(sta->addr), sta->aid);
 581 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 582         /* Send all buffered frames to the station */
 583         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
 584                 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 585                 sent++;
 586                 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
 587                 dev_queue_xmit(skb);
 588         }
 589         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
 590                 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 591                 local->total_ps_buffered--;
 592                 sent++;
 593 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 594                 printk(KERN_DEBUG "%s: STA " MAC_FMT " aid %d send PS frame "
 595                        "since STA not sleeping anymore\n", dev->name,
 596                        MAC_ARG(sta->addr), sta->aid);
 597 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 598                 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
 599                 dev_queue_xmit(skb);
 600         }
 601
 602         return sent;
 603 }
 604
 605 static ieee80211_txrx_result
 606 ieee80211_rx_h_sta_process(struct ieee80211_txrx_data *rx)
 607 {
 608         struct sta_info *sta = rx->sta;
 609         struct net_device *dev = rx->dev;
 610         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 611
 612         if (!sta)
 613                 return TXRX_CONTINUE;
 614
 615         /* Update last_rx only for IBSS packets which are for the current
 616          * BSSID to avoid keeping the current IBSS network alive in cases where
 617          * other STAs are using different BSSID. */
 618         if (rx->sdata->type == IEEE80211_IF_TYPE_IBSS) {
 619                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len);
 620                 if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0)
 621                         sta->last_rx = jiffies;
 622         } else
 623         if (!is_multicast_ether_addr(hdr->addr1) ||
 624             rx->sdata->type == IEEE80211_IF_TYPE_STA) {
 625                 /* Update last_rx only for unicast frames in order to prevent
 626                  * the Probe Request frames (the only broadcast frames from a
 627                  * STA in infrastructure mode) from keeping a connection alive.
 628                  */
 629                 sta->last_rx = jiffies;
 630         }
 631
 632         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 633                 return TXRX_CONTINUE;
 634
 635         sta->rx_fragments++;
 636         sta->rx_bytes += rx->skb->len;
 637         sta->last_rssi = rx->u.rx.status->ssi;
 638         sta->last_signal = rx->u.rx.status->signal;
 639         sta->last_noise = rx->u.rx.status->noise;
 640
 641         if (!(rx->fc & IEEE80211_FCTL_MOREFRAGS)) {
 642                 /* Change STA power saving mode only in the end of a frame
 643                  * exchange sequence */
 644                 if ((sta->flags & WLAN_STA_PS) && !(rx->fc & IEEE80211_FCTL_PM))
 645                         rx->u.rx.sent_ps_buffered += ap_sta_ps_end(dev, sta);
 646                 else if (!(sta->flags & WLAN_STA_PS) &&
 647                          (rx->fc & IEEE80211_FCTL_PM))
 648                         ap_sta_ps_start(dev, sta);
 649         }
 650
 651         /* Drop data::nullfunc frames silently, since they are used only to
 652          * control station power saving mode. */
 653         if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 654             (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_NULLFUNC) {
 655                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
 656                 /* Update counter and free packet here to avoid counting this
 657                  * as a dropped packed. */
 658                 sta->rx_packets++;
 659                 dev_kfree_skb(rx->skb);
 660                 return TXRX_QUEUED;
 661         }
 662
 663         return TXRX_CONTINUE;
 664 } /* ieee80211_rx_h_sta_process */
 665
 666 static inline struct ieee80211_fragment_entry *
 667 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
 668                          unsigned int frag, unsigned int seq, int rx_queue,
 669                          struct sk_buff **skb)
 670 {
 671         struct ieee80211_fragment_entry *entry;
 672         int idx;
 673
 674         idx = sdata->fragment_next;
 675         entry = &sdata->fragments[sdata->fragment_next++];
 676         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
 677                 sdata->fragment_next = 0;
 678
 679         if (!skb_queue_empty(&entry->skb_list)) {
 680 #ifdef CONFIG_MAC80211_DEBUG
 681                 struct ieee80211_hdr *hdr =
 682                         (struct ieee80211_hdr *) entry->skb_list.next->data;
 683                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
 684                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
 685                        "addr1=" MAC_FMT " addr2=" MAC_FMT "\n",
 686                        sdata->dev->name, idx,
 687                        jiffies - entry->first_frag_time, entry->seq,
 688                        entry->last_frag, MAC_ARG(hdr->addr1),
 689                        MAC_ARG(hdr->addr2));
 690 #endif /* CONFIG_MAC80211_DEBUG */
 691                 __skb_queue_purge(&entry->skb_list);
 692         }
 693
 694         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
 695         *skb = NULL;
 696         entry->first_frag_time = jiffies;
 697         entry->seq = seq;
 698         entry->rx_queue = rx_queue;
 699         entry->last_frag = frag;
 700         entry->ccmp = 0;
 701         entry->extra_len = 0;
 702
 703         return entry;
 704 }
 705
 706 static inline struct ieee80211_fragment_entry *
 707 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
 708                           u16 fc, unsigned int frag, unsigned int seq,
 709                           int rx_queue, struct ieee80211_hdr *hdr)
 710 {
 711         struct ieee80211_fragment_entry *entry;
 712         int i, idx;
 713
 714         idx = sdata->fragment_next;
 715         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
 716                 struct ieee80211_hdr *f_hdr;
 717                 u16 f_fc;
 718
 719                 idx--;
 720                 if (idx < 0)
 721                         idx = IEEE80211_FRAGMENT_MAX - 1;
 722
 723                 entry = &sdata->fragments[idx];
 724                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
 725                     entry->rx_queue != rx_queue ||
 726                     entry->last_frag + 1 != frag)
 727                         continue;
 728
 729                 f_hdr = (struct ieee80211_hdr *) entry->skb_list.next->data;
 730                 f_fc = le16_to_cpu(f_hdr->frame_control);
 731
 732                 if ((fc & IEEE80211_FCTL_FTYPE) != (f_fc & IEEE80211_FCTL_FTYPE) ||
 733                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
 734                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
 735                         continue;
 736
 737                 if (entry->first_frag_time + 2 * HZ < jiffies) {
 738                         __skb_queue_purge(&entry->skb_list);
 739                         continue;
 740                 }
 741                 return entry;
 742         }
 743
 744         return NULL;
 745 }
 746
 747 static ieee80211_txrx_result
 748 ieee80211_rx_h_defragment(struct ieee80211_txrx_data *rx)
 749 {
 750         struct ieee80211_hdr *hdr;
 751         u16 sc;
 752         unsigned int frag, seq;
 753         struct ieee80211_fragment_entry *entry;
 754         struct sk_buff *skb;
 755
 756         hdr = (struct ieee80211_hdr *) rx->skb->data;
 757         sc = le16_to_cpu(hdr->seq_ctrl);
 758         frag = sc & IEEE80211_SCTL_FRAG;
 759
 760         if (likely((!(rx->fc & IEEE80211_FCTL_MOREFRAGS) && frag == 0) ||
 761                    (rx->skb)->len < 24 ||
 762                    is_multicast_ether_addr(hdr->addr1))) {
 763                 /* not fragmented */
 764                 goto out;
 765         }
 766         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
 767
 768         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
 769
 770         if (frag == 0) {
 771                 /* This is the first fragment of a new frame. */
 772                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
 773                                                  rx->u.rx.queue, &(rx->skb));
 774                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
 775                     (rx->fc & IEEE80211_FCTL_PROTECTED)) {
 776                         /* Store CCMP PN so that we can verify that the next
 777                          * fragment has a sequential PN value. */
 778                         entry->ccmp = 1;
 779                         memcpy(entry->last_pn,
 780                                rx->key->u.ccmp.rx_pn[rx->u.rx.queue],
 781                                CCMP_PN_LEN);
 782                 }
 783                 return TXRX_QUEUED;
 784         }
 785
 786         /* This is a fragment for a frame that should already be pending in
 787          * fragment cache. Add this fragment to the end of the pending entry.
 788          */
 789         entry = ieee80211_reassemble_find(rx->sdata, rx->fc, frag, seq,
 790                                           rx->u.rx.queue, hdr);
 791         if (!entry) {
 792                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 793                 return TXRX_DROP;
 794         }
 795
 796         /* Verify that MPDUs within one MSDU have sequential PN values.
 797          * (IEEE 802.11i, 8.3.3.4.5) */
 798         if (entry->ccmp) {
 799                 int i;
 800                 u8 pn[CCMP_PN_LEN], *rpn;
 801                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
 802                         return TXRX_DROP;
 803                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
 804                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
 805                         pn[i]++;
 806                         if (pn[i])
 807                                 break;
 808                 }
 809                 rpn = rx->key->u.ccmp.rx_pn[rx->u.rx.queue];
 810                 if (memcmp(pn, rpn, CCMP_PN_LEN) != 0) {
 811                         if (net_ratelimit())
 812                                 printk(KERN_DEBUG "%s: defrag: CCMP PN not "
 813                                        "sequential A2=" MAC_FMT
 814                                        " PN=%02x%02x%02x%02x%02x%02x "
 815                                        "(expected %02x%02x%02x%02x%02x%02x)\n",
 816                                        rx->dev->name, MAC_ARG(hdr->addr2),
 817                                        rpn[0], rpn[1], rpn[2], rpn[3], rpn[4],
 818                                        rpn[5], pn[0], pn[1], pn[2], pn[3],
 819                                        pn[4], pn[5]);
 820                         return TXRX_DROP;
 821                 }
 822                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
 823         }
 824
 825         skb_pull(rx->skb, ieee80211_get_hdrlen(rx->fc));
 826         __skb_queue_tail(&entry->skb_list, rx->skb);
 827         entry->last_frag = frag;
 828         entry->extra_len += rx->skb->len;
 829         if (rx->fc & IEEE80211_FCTL_MOREFRAGS) {
 830                 rx->skb = NULL;
 831                 return TXRX_QUEUED;
 832         }
 833
 834         rx->skb = __skb_dequeue(&entry->skb_list);
 835         if (skb_tailroom(rx->skb) < entry->extra_len) {
 836                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
 837                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
 838                                               GFP_ATOMIC))) {
 839                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 840                         __skb_queue_purge(&entry->skb_list);
 841                         return TXRX_DROP;
 842                 }
 843         }
 844         while ((skb = __skb_dequeue(&entry->skb_list))) {
 845                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
 846                 dev_kfree_skb(skb);
 847         }
 848
 849         /* Complete frame has been reassembled - process it now */
 850         rx->flags |= IEEE80211_TXRXD_FRAGMENTED;
 851
 852  out:
 853         if (rx->sta)
 854                 rx->sta->rx_packets++;
 855         if (is_multicast_ether_addr(hdr->addr1))
 856                 rx->local->dot11MulticastReceivedFrameCount++;
 857         else
 858                 ieee80211_led_rx(rx->local);
 859         return TXRX_CONTINUE;
 860 }
 861
 862 static ieee80211_txrx_result
 863 ieee80211_rx_h_ps_poll(struct ieee80211_txrx_data *rx)
 864 {
 865         struct sk_buff *skb;
 866         int no_pending_pkts;
 867
 868         if (likely(!rx->sta ||
 869                    (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL ||
 870                    (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PSPOLL ||
 871                    !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)))
 872                 return TXRX_CONTINUE;
 873
 874         skb = skb_dequeue(&rx->sta->tx_filtered);
 875         if (!skb) {
 876                 skb = skb_dequeue(&rx->sta->ps_tx_buf);
 877                 if (skb)
 878                         rx->local->total_ps_buffered--;
 879         }
 880         no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
 881                 skb_queue_empty(&rx->sta->ps_tx_buf);
 882
 883         if (skb) {
 884                 struct ieee80211_hdr *hdr =
 885                         (struct ieee80211_hdr *) skb->data;
 886
 887                 /* tell TX path to send one frame even though the STA may
 888                  * still remain is PS mode after this frame exchange */
 889                 rx->sta->pspoll = 1;
 890
 891 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 892                 printk(KERN_DEBUG "STA " MAC_FMT " aid %d: PS Poll (entries "
 893                        "after %d)\n",
 894                        MAC_ARG(rx->sta->addr), rx->sta->aid,
 895                        skb_queue_len(&rx->sta->ps_tx_buf));
 896 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 897
 898                 /* Use MoreData flag to indicate whether there are more
 899                  * buffered frames for this STA */
 900                 if (no_pending_pkts) {
 901                         hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
 902                         rx->sta->flags &= ~WLAN_STA_TIM;
 903                 } else
 904                         hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
 905
 906                 dev_queue_xmit(skb);
 907
 908                 if (no_pending_pkts) {
 909                         if (rx->local->ops->set_tim)
 910                                 rx->local->ops->set_tim(local_to_hw(rx->local),
 911                                                        rx->sta->aid, 0);
 912                         if (rx->sdata->bss)
 913                                 bss_tim_clear(rx->local, rx->sdata->bss, rx->sta->aid);
 914                 }
 915 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 916         } else if (!rx->u.rx.sent_ps_buffered) {
 917                 printk(KERN_DEBUG "%s: STA " MAC_FMT " sent PS Poll even "
 918                        "though there is no buffered frames for it\n",
 919                        rx->dev->name, MAC_ARG(rx->sta->addr));
 920 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 921
 922         }
 923
 924         /* Free PS Poll skb here instead of returning TXRX_DROP that would
 925          * count as an dropped frame. */
 926         dev_kfree_skb(rx->skb);
 927
 928         return TXRX_QUEUED;
 929 }
 930
 931 static ieee80211_txrx_result
 932 ieee80211_rx_h_remove_qos_control(struct ieee80211_txrx_data *rx)
 933 {
 934         u16 fc = rx->fc;
 935         u8 *data = rx->skb->data;
 936         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) data;
 937
 938         if (!WLAN_FC_IS_QOS_DATA(fc))
 939                 return TXRX_CONTINUE;
 940
 941         /* remove the qos control field, update frame type and meta-data */
 942         memmove(data + 2, data, ieee80211_get_hdrlen(fc) - 2);
 943         hdr = (struct ieee80211_hdr *) skb_pull(rx->skb, 2);
 944         /* change frame type to non QOS */
 945         rx->fc = fc &= ~IEEE80211_STYPE_QOS_DATA;
 946         hdr->frame_control = cpu_to_le16(fc);
 947
 948         return TXRX_CONTINUE;
 949 }
 950
 951 static ieee80211_txrx_result
 952 ieee80211_rx_h_802_1x_pae(struct ieee80211_txrx_data *rx)
 953 {
 954         if (rx->sdata->eapol && ieee80211_is_eapol(rx->skb) &&
 955             rx->sdata->type != IEEE80211_IF_TYPE_STA &&
 956             (rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 957                 return TXRX_CONTINUE;
 958
 959         if (unlikely(rx->sdata->ieee802_1x &&
 960                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 961                      (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
 962                      (!rx->sta || !(rx->sta->flags & WLAN_STA_AUTHORIZED)) &&
 963                      !ieee80211_is_eapol(rx->skb))) {
 964 #ifdef CONFIG_MAC80211_DEBUG
 965                 struct ieee80211_hdr *hdr =
 966                         (struct ieee80211_hdr *) rx->skb->data;
 967                 printk(KERN_DEBUG "%s: dropped frame from " MAC_FMT
 968                        " (unauthorized port)\n", rx->dev->name,
 969                        MAC_ARG(hdr->addr2));
 970 #endif /* CONFIG_MAC80211_DEBUG */
 971                 return TXRX_DROP;
 972         }
 973
 974         return TXRX_CONTINUE;
 975 }
 976
 977 static ieee80211_txrx_result
 978 ieee80211_rx_h_drop_unencrypted(struct ieee80211_txrx_data *rx)
 979 {
 980         /*
 981          * Pass through unencrypted frames if the hardware has
 982          * decrypted them already.
 983          */
 984         if (rx->u.rx.status->flag & RX_FLAG_DECRYPTED)
 985                 return TXRX_CONTINUE;
 986
 987         /* Drop unencrypted frames if key is set. */
 988         if (unlikely(!(rx->fc & IEEE80211_FCTL_PROTECTED) &&
 989                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 990                      (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
 991                      rx->sdata->drop_unencrypted &&
 992                      (rx->sdata->eapol == 0 || !ieee80211_is_eapol(rx->skb)))) {
 993                 if (net_ratelimit())
 994                         printk(KERN_DEBUG "%s: RX non-WEP frame, but expected "
 995                                "encryption\n", rx->dev->name);
 996                 return TXRX_DROP;
 997         }
 998         return TXRX_CONTINUE;
 999 }
1000
1001 static ieee80211_txrx_result
1002 ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
1003 {
1004         struct net_device *dev = rx->dev;
1005         struct ieee80211_local *local = rx->local;
1006         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
1007         u16 fc, hdrlen, ethertype;
1008         u8 *payload;
1009         u8 dst[ETH_ALEN];
1010         u8 src[ETH_ALEN];
1011         struct sk_buff *skb = rx->skb, *skb2;
1012         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1013
1014         fc = rx->fc;
1015         if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
1016                 return TXRX_CONTINUE;
1017
1018         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1019                 return TXRX_DROP;
1020
1021         hdrlen = ieee80211_get_hdrlen(fc);
1022
1023         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
1024          * header
1025          * IEEE 802.11 address fields:
1026          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
1027          *   0     0   DA    SA    BSSID n/a
1028          *   0     1   DA    BSSID SA    n/a
1029          *   1     0   BSSID SA    DA    n/a
1030          *   1     1   RA    TA    DA    SA
1031          */
1032
1033         switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
1034         case IEEE80211_FCTL_TODS:
1035                 /* BSSID SA DA */
1036                 memcpy(dst, hdr->addr3, ETH_ALEN);
1037                 memcpy(src, hdr->addr2, ETH_ALEN);
1038
1039                 if (unlikely(sdata->type != IEEE80211_IF_TYPE_AP &&
1040                              sdata->type != IEEE80211_IF_TYPE_VLAN)) {
1041                         if (net_ratelimit())
1042                                 printk(KERN_DEBUG "%s: dropped ToDS frame "
1043                                        "(BSSID=" MAC_FMT
1044                                        " SA=" MAC_FMT
1045                                        " DA=" MAC_FMT ")\n",
1046                                        dev->name,
1047                                        MAC_ARG(hdr->addr1),
1048                                        MAC_ARG(hdr->addr2),
1049                                        MAC_ARG(hdr->addr3));
1050                         return TXRX_DROP;
1051                 }
1052                 break;
1053         case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
1054                 /* RA TA DA SA */
1055                 memcpy(dst, hdr->addr3, ETH_ALEN);
1056                 memcpy(src, hdr->addr4, ETH_ALEN);
1057
1058                 if (unlikely(sdata->type != IEEE80211_IF_TYPE_WDS)) {
1059                         if (net_ratelimit())
1060                                 printk(KERN_DEBUG "%s: dropped FromDS&ToDS "
1061                                        "frame (RA=" MAC_FMT
1062                                        " TA=" MAC_FMT " DA=" MAC_FMT
1063                                        " SA=" MAC_FMT ")\n",
1064                                        rx->dev->name,
1065                                        MAC_ARG(hdr->addr1),
1066                                        MAC_ARG(hdr->addr2),
1067                                        MAC_ARG(hdr->addr3),
1068                                        MAC_ARG(hdr->addr4));
1069                         return TXRX_DROP;
1070                 }
1071                 break;
1072         case IEEE80211_FCTL_FROMDS:
1073                 /* DA BSSID SA */
1074                 memcpy(dst, hdr->addr1, ETH_ALEN);
1075                 memcpy(src, hdr->addr3, ETH_ALEN);
1076
1077                 if (sdata->type != IEEE80211_IF_TYPE_STA ||
1078                     (is_multicast_ether_addr(dst) &&
1079                      !compare_ether_addr(src, dev->dev_addr)))
1080                         return TXRX_DROP;
1081                 break;
1082         case 0:
1083                 /* DA SA BSSID */
1084                 memcpy(dst, hdr->addr1, ETH_ALEN);
1085                 memcpy(src, hdr->addr2, ETH_ALEN);
1086
1087                 if (sdata->type != IEEE80211_IF_TYPE_IBSS) {
1088                         if (net_ratelimit()) {
1089                                 printk(KERN_DEBUG "%s: dropped IBSS frame (DA="
1090                                        MAC_FMT " SA=" MAC_FMT " BSSID=" MAC_FMT
1091                                        ")\n",
1092                                        dev->name, MAC_ARG(hdr->addr1),
1093                                        MAC_ARG(hdr->addr2),
1094                                        MAC_ARG(hdr->addr3));
1095                         }
1096                         return TXRX_DROP;
1097                 }
1098                 break;
1099         }
1100
1101         payload = skb->data + hdrlen;
1102
1103         if (unlikely(skb->len - hdrlen < 8)) {
1104                 if (net_ratelimit()) {
1105                         printk(KERN_DEBUG "%s: RX too short data frame "
1106                                "payload\n", dev->name);
1107                 }
1108                 return TXRX_DROP;
1109         }
1110
1111         ethertype = (payload[6] << 8) | payload[7];
1112
1113         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1114                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1115                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1116                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1117                  * replace EtherType */
1118                 skb_pull(skb, hdrlen + 6);
1119                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1120                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1121         } else {
1122                 struct ethhdr *ehdr;
1123                 __be16 len;
1124                 skb_pull(skb, hdrlen);
1125                 len = htons(skb->len);
1126                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1127                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1128                 memcpy(ehdr->h_source, src, ETH_ALEN);
1129                 ehdr->h_proto = len;
1130         }
1131         skb->dev = dev;
1132
1133         skb2 = NULL;
1134
1135         dev->stats.rx_packets++;
1136         dev->stats.rx_bytes += skb->len;
1137
1138         if (local->bridge_packets && (sdata->type == IEEE80211_IF_TYPE_AP
1139             || sdata->type == IEEE80211_IF_TYPE_VLAN) &&
1140             (rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
1141                 if (is_multicast_ether_addr(skb->data)) {
1142                         /* send multicast frames both to higher layers in
1143                          * local net stack and back to the wireless media */
1144                         skb2 = skb_copy(skb, GFP_ATOMIC);
1145                         if (!skb2 && net_ratelimit())
1146                                 printk(KERN_DEBUG "%s: failed to clone "
1147                                        "multicast frame\n", dev->name);
1148                 } else {
1149                         struct sta_info *dsta;
1150                         dsta = sta_info_get(local, skb->data);
1151                         if (dsta && !dsta->dev) {
1152                                 if (net_ratelimit())
1153                                         printk(KERN_DEBUG "Station with null "
1154                                                "dev structure!\n");
1155                         } else if (dsta && dsta->dev == dev) {
1156                                 /* Destination station is associated to this
1157                                  * AP, so send the frame directly to it and
1158                                  * do not pass the frame to local net stack.
1159                                  */
1160                                 skb2 = skb;
1161                                 skb = NULL;
1162                         }
1163                         if (dsta)
1164                                 sta_info_put(dsta);
1165                 }
1166         }
1167
1168         if (skb) {
1169                 /* deliver to local stack */
1170                 skb->protocol = eth_type_trans(skb, dev);
1171                 memset(skb->cb, 0, sizeof(skb->cb));
1172                 netif_rx(skb);
1173         }
1174
1175         if (skb2) {
1176                 /* send to wireless media */
1177                 skb2->protocol = __constant_htons(ETH_P_802_3);
1178                 skb_set_network_header(skb2, 0);
1179                 skb_set_mac_header(skb2, 0);
1180                 dev_queue_xmit(skb2);
1181         }
1182
1183         return TXRX_QUEUED;
1184 }
1185
1186 static ieee80211_txrx_result
1187 ieee80211_rx_h_mgmt(struct ieee80211_txrx_data *rx)
1188 {
1189         struct ieee80211_sub_if_data *sdata;
1190
1191         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
1192                 return TXRX_DROP;
1193
1194         sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1195         if ((sdata->type == IEEE80211_IF_TYPE_STA ||
1196              sdata->type == IEEE80211_IF_TYPE_IBSS) &&
1197             !(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME))
1198                 ieee80211_sta_rx_mgmt(rx->dev, rx->skb, rx->u.rx.status);
1199         else
1200                 return TXRX_DROP;
1201
1202         return TXRX_QUEUED;
1203 }
1204
1205 static inline ieee80211_txrx_result __ieee80211_invoke_rx_handlers(
1206                                 struct ieee80211_local *local,
1207                                 ieee80211_rx_handler *handlers,
1208                                 struct ieee80211_txrx_data *rx,
1209                                 struct sta_info *sta)
1210 {
1211         ieee80211_rx_handler *handler;
1212         ieee80211_txrx_result res = TXRX_DROP;
1213
1214         for (handler = handlers; *handler != NULL; handler++) {
1215                 res = (*handler)(rx);
1216
1217                 switch (res) {
1218                 case TXRX_CONTINUE:
1219                         continue;
1220                 case TXRX_DROP:
1221                         I802_DEBUG_INC(local->rx_handlers_drop);
1222                         if (sta)
1223                                 sta->rx_dropped++;
1224                         break;
1225                 case TXRX_QUEUED:
1226                         I802_DEBUG_INC(local->rx_handlers_queued);
1227                         break;
1228                 }
1229                 break;
1230         }
1231
1232         if (res == TXRX_DROP)
1233                 dev_kfree_skb(rx->skb);
1234         return res;
1235 }
1236
1237 static inline void ieee80211_invoke_rx_handlers(struct ieee80211_local *local,
1238                                                 ieee80211_rx_handler *handlers,
1239                                                 struct ieee80211_txrx_data *rx,
1240                                                 struct sta_info *sta)
1241 {
1242         if (__ieee80211_invoke_rx_handlers(local, handlers, rx, sta) ==
1243             TXRX_CONTINUE)
1244                 dev_kfree_skb(rx->skb);
1245 }
1246
1247 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1248                                             struct ieee80211_hdr *hdr,
1249                                             struct sta_info *sta,
1250                                             struct ieee80211_txrx_data *rx)
1251 {
1252         int keyidx, hdrlen;
1253
1254         hdrlen = ieee80211_get_hdrlen_from_skb(rx->skb);
1255         if (rx->skb->len >= hdrlen + 4)
1256                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1257         else
1258                 keyidx = -1;
1259
1260         if (net_ratelimit())
1261                 printk(KERN_DEBUG "%s: TKIP hwaccel reported Michael MIC "
1262                        "failure from " MAC_FMT " to " MAC_FMT " keyidx=%d\n",
1263                        dev->name, MAC_ARG(hdr->addr2), MAC_ARG(hdr->addr1),
1264                        keyidx);
1265
1266         if (!sta) {
1267                 /*
1268                  * Some hardware seem to generate incorrect Michael MIC
1269                  * reports; ignore them to avoid triggering countermeasures.
1270                  */
1271                 if (net_ratelimit())
1272                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1273                                "error for unknown address " MAC_FMT "\n",
1274                                dev->name, MAC_ARG(hdr->addr2));
1275                 goto ignore;
1276         }
1277
1278         if (!(rx->fc & IEEE80211_FCTL_PROTECTED)) {
1279                 if (net_ratelimit())
1280                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1281                                "error for a frame with no PROTECTED flag (src "
1282                                MAC_FMT ")\n", dev->name, MAC_ARG(hdr->addr2));
1283                 goto ignore;
1284         }
1285
1286         if (rx->sdata->type == IEEE80211_IF_TYPE_AP && keyidx) {
1287                 /*
1288                  * APs with pairwise keys should never receive Michael MIC
1289                  * errors for non-zero keyidx because these are reserved for
1290                  * group keys and only the AP is sending real multicast
1291                  * frames in the BSS.
1292                  */
1293                 if (net_ratelimit())
1294                         printk(KERN_DEBUG "%s: ignored Michael MIC error for "
1295                                "a frame with non-zero keyidx (%d)"
1296                                " (src " MAC_FMT ")\n", dev->name, keyidx,
1297                                MAC_ARG(hdr->addr2));
1298                 goto ignore;
1299         }
1300
1301         if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
1302             ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
1303              (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)) {
1304                 if (net_ratelimit())
1305                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1306                                "error for a frame that cannot be encrypted "
1307                                "(fc=0x%04x) (src " MAC_FMT ")\n",
1308                                dev->name, rx->fc, MAC_ARG(hdr->addr2));
1309                 goto ignore;
1310         }
1311
1312         mac80211_ev_michael_mic_failure(rx->dev, keyidx, hdr);
1313  ignore:
1314         dev_kfree_skb(rx->skb);
1315         rx->skb = NULL;
1316 }
1317
1318 ieee80211_rx_handler ieee80211_rx_handlers[] =
1319 {
1320         ieee80211_rx_h_if_stats,
1321         ieee80211_rx_h_passive_scan,
1322         ieee80211_rx_h_check,
1323         ieee80211_rx_h_decrypt,
1324         ieee80211_rx_h_sta_process,
1325         ieee80211_rx_h_defragment,
1326         ieee80211_rx_h_ps_poll,
1327         ieee80211_rx_h_michael_mic_verify,
1328         /* this must be after decryption - so header is counted in MPDU mic
1329          * must be before pae and data, so QOS_DATA format frames
1330          * are not passed to user space by these functions
1331          */
1332         ieee80211_rx_h_remove_qos_control,
1333         ieee80211_rx_h_802_1x_pae,
1334         ieee80211_rx_h_drop_unencrypted,
1335         ieee80211_rx_h_data,
1336         ieee80211_rx_h_mgmt,
1337         NULL
1338 };
1339
1340 /* main receive path */
1341
1342 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
1343                                 u8 *bssid, struct ieee80211_txrx_data *rx,
1344                                 struct ieee80211_hdr *hdr)
1345 {
1346         int multicast = is_multicast_ether_addr(hdr->addr1);
1347
1348         switch (sdata->type) {
1349         case IEEE80211_IF_TYPE_STA:
1350                 if (!bssid)
1351                         return 0;
1352                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1353                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1354                                 return 0;
1355                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1356                 } else if (!multicast &&
1357                            compare_ether_addr(sdata->dev->dev_addr,
1358                                               hdr->addr1) != 0) {
1359                         if (!(sdata->dev->flags & IFF_PROMISC))
1360                                 return 0;
1361                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1362                 }
1363                 break;
1364         case IEEE80211_IF_TYPE_IBSS:
1365                 if (!bssid)
1366                         return 0;
1367                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1368                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1369                                 return 0;
1370                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1371                 } else if (!multicast &&
1372                            compare_ether_addr(sdata->dev->dev_addr,
1373                                               hdr->addr1) != 0) {
1374                         if (!(sdata->dev->flags & IFF_PROMISC))
1375                                 return 0;
1376                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1377                 } else if (!rx->sta)
1378                         rx->sta = ieee80211_ibss_add_sta(sdata->dev, rx->skb,
1379                                                          bssid, hdr->addr2);
1380                 break;
1381         case IEEE80211_IF_TYPE_VLAN:
1382         case IEEE80211_IF_TYPE_AP:
1383                 if (!bssid) {
1384                         if (compare_ether_addr(sdata->dev->dev_addr,
1385                                                hdr->addr1))
1386                                 return 0;
1387                 } else if (!ieee80211_bssid_match(bssid,
1388                                         sdata->dev->dev_addr)) {
1389                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1390                                 return 0;
1391                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1392                 }
1393                 if (sdata->dev == sdata->local->mdev &&
1394                     !(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1395                         /* do not receive anything via
1396                          * master device when not scanning */
1397                         return 0;
1398                 break;
1399         case IEEE80211_IF_TYPE_WDS:
1400                 if (bssid ||
1401                     (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
1402                         return 0;
1403                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
1404                         return 0;
1405                 break;
1406         case IEEE80211_IF_TYPE_MNTR:
1407                 /* take everything */
1408                 break;
1409         case IEEE80211_IF_TYPE_INVALID:
1410                 /* should never get here */
1411                 WARN_ON(1);
1412                 break;
1413         }
1414
1415         return 1;
1416 }
1417
1418 /*
1419  * This is the receive path handler. It is called by a low level driver when an
1420  * 802.11 MPDU is received from the hardware.
1421  */
1422 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
1423                     struct ieee80211_rx_status *status)
1424 {
1425         struct ieee80211_local *local = hw_to_local(hw);
1426         struct ieee80211_sub_if_data *sdata;
1427         struct sta_info *sta;
1428         struct ieee80211_hdr *hdr;
1429         struct ieee80211_txrx_data rx;
1430         u16 type;
1431         int prepres;
1432         struct ieee80211_sub_if_data *prev = NULL;
1433         struct sk_buff *skb_new;
1434         u8 *bssid;
1435
1436         /*
1437          * key references and virtual interfaces are protected using RCU
1438          * and this requires that we are in a read-side RCU section during
1439          * receive processing
1440          */
1441         rcu_read_lock();
1442
1443         /*
1444          * Frames with failed FCS/PLCP checksum are not returned,
1445          * all other frames are returned without radiotap header
1446          * if it was previously present.
1447          * Also, frames with less than 16 bytes are dropped.
1448          */
1449         skb = ieee80211_rx_monitor(local, skb, status);
1450         if (!skb) {
1451                 rcu_read_unlock();
1452                 return;
1453         }
1454
1455         hdr = (struct ieee80211_hdr *) skb->data;
1456         memset(&rx, 0, sizeof(rx));
1457         rx.skb = skb;
1458         rx.local = local;
1459
1460         rx.u.rx.status = status;
1461         rx.fc = le16_to_cpu(hdr->frame_control);
1462         type = rx.fc & IEEE80211_FCTL_FTYPE;
1463
1464         if (type == IEEE80211_FTYPE_DATA || type == IEEE80211_FTYPE_MGMT)
1465                 local->dot11ReceivedFragmentCount++;
1466
1467         sta = rx.sta = sta_info_get(local, hdr->addr2);
1468         if (sta) {
1469                 rx.dev = rx.sta->dev;
1470                 rx.sdata = IEEE80211_DEV_TO_SUB_IF(rx.dev);
1471         }
1472
1473         if ((status->flag & RX_FLAG_MMIC_ERROR)) {
1474                 ieee80211_rx_michael_mic_report(local->mdev, hdr, sta, &rx);
1475                 goto end;
1476         }
1477
1478         if (unlikely(local->sta_scanning))
1479                 rx.flags |= IEEE80211_TXRXD_RXIN_SCAN;
1480
1481         if (__ieee80211_invoke_rx_handlers(local, local->rx_pre_handlers, &rx,
1482                                            sta) != TXRX_CONTINUE)
1483                 goto end;
1484         skb = rx.skb;
1485
1486         if (sta && !(sta->flags & (WLAN_STA_WDS | WLAN_STA_ASSOC_AP)) &&
1487             !atomic_read(&local->iff_promiscs) &&
1488             !is_multicast_ether_addr(hdr->addr1)) {
1489                 rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
1490                 ieee80211_invoke_rx_handlers(local, local->rx_handlers, &rx,
1491                                              rx.sta);
1492                 sta_info_put(sta);
1493                 rcu_read_unlock();
1494                 return;
1495         }
1496
1497         bssid = ieee80211_get_bssid(hdr, skb->len);
1498
1499         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1500                 if (!netif_running(sdata->dev))
1501                         continue;
1502
1503                 if (sdata->type == IEEE80211_IF_TYPE_MNTR)
1504                         continue;
1505
1506                 rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
1507                 prepres = prepare_for_handlers(sdata, bssid, &rx, hdr);
1508                 /* prepare_for_handlers can change sta */
1509                 sta = rx.sta;
1510
1511                 if (!prepres)
1512                         continue;
1513
1514                 /*
1515                  * frame is destined for this interface, but if it's not
1516                  * also for the previous one we handle that after the
1517                  * loop to avoid copying the SKB once too much
1518                  */
1519
1520                 if (!prev) {
1521                         prev = sdata;
1522                         continue;
1523                 }
1524
1525                 /*
1526                  * frame was destined for the previous interface
1527                  * so invoke RX handlers for it
1528                  */
1529
1530                 skb_new = skb_copy(skb, GFP_ATOMIC);
1531                 if (!skb_new) {
1532                         if (net_ratelimit())
1533                                 printk(KERN_DEBUG "%s: failed to copy "
1534                                        "multicast frame for %s",
1535                                        wiphy_name(local->hw.wiphy),
1536                                        prev->dev->name);
1537                         continue;
1538                 }
1539                 rx.skb = skb_new;
1540                 rx.dev = prev->dev;
1541                 rx.sdata = prev;
1542                 ieee80211_invoke_rx_handlers(local, local->rx_handlers,
1543                                              &rx, sta);
1544                 prev = sdata;
1545         }
1546         if (prev) {
1547                 rx.skb = skb;
1548                 rx.dev = prev->dev;
1549                 rx.sdata = prev;
1550                 ieee80211_invoke_rx_handlers(local, local->rx_handlers,
1551                                              &rx, sta);
1552         } else
1553                 dev_kfree_skb(skb);
1554
1555  end:
1556         rcu_read_unlock();
1557
1558         if (sta)
1559                 sta_info_put(sta);
1560 }
1561 EXPORT_SYMBOL(__ieee80211_rx);
1562
1563 /* This is a version of the rx handler that can be called from hard irq
1564  * context. Post the skb on the queue and schedule the tasklet */
1565 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
1566                           struct ieee80211_rx_status *status)
1567 {
1568         struct ieee80211_local *local = hw_to_local(hw);
1569
1570         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
1571
1572         skb->dev = local->mdev;
1573         /* copy status into skb->cb for use by tasklet */
1574         memcpy(skb->cb, status, sizeof(*status));
1575         skb->pkt_type = IEEE80211_RX_MSG;
1576         skb_queue_tail(&local->skb_queue, skb);
1577         tasklet_schedule(&local->tasklet);
1578 }
1579 EXPORT_SYMBOL(ieee80211_rx_irqsafe);