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 "ieee80211_common.h"
  23 #include "wep.h"
  24 #include "wpa.h"
  25 #include "tkip.h"
  26 #include "wme.h"
  27
  28 /* pre-rx handlers
  29  *
  30  * these don't have dev/sdata fields in the rx data
  31  * The sta value should also not be used because it may
  32  * be NULL even though a STA (in IBSS mode) will be added.
  33  */
  34
  35 static ieee80211_txrx_result
  36 ieee80211_rx_h_parse_qos(struct ieee80211_txrx_data *rx)
  37 {
  38         u8 *data = rx->skb->data;
  39         int tid;
  40
  41         /* does the frame have a qos control field? */
  42         if (WLAN_FC_IS_QOS_DATA(rx->fc)) {
  43                 u8 *qc = data + ieee80211_get_hdrlen(rx->fc) - QOS_CONTROL_LEN;
  44                 /* frame has qos control */
  45                 tid = qc[0] & QOS_CONTROL_TID_MASK;
  46         } else {
  47                 if (unlikely((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT)) {
  48                         /* Separate TID for management frames */
  49                         tid = NUM_RX_DATA_QUEUES - 1;
  50                 } else {
  51                         /* no qos control present */
  52                         tid = 0; /* 802.1d - Best Effort */
  53                 }
  54         }
  55
  56         I802_DEBUG_INC(rx->local->wme_rx_queue[tid]);
  57         /* only a debug counter, sta might not be assigned properly yet */
  58         if (rx->sta)
  59                 I802_DEBUG_INC(rx->sta->wme_rx_queue[tid]);
  60
  61         rx->u.rx.queue = tid;
  62         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
  63          * For now, set skb->priority to 0 for other cases. */
  64         rx->skb->priority = (tid > 7) ? 0 : tid;
  65
  66         return TXRX_CONTINUE;
  67 }
  68
  69 static ieee80211_txrx_result
  70 ieee80211_rx_h_load_stats(struct ieee80211_txrx_data *rx)
  71 {
  72         struct ieee80211_local *local = rx->local;
  73         struct sk_buff *skb = rx->skb;
  74         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
  75         u32 load = 0, hdrtime;
  76         struct ieee80211_rate *rate;
  77         struct ieee80211_hw_mode *mode = local->hw.conf.mode;
  78         int i;
  79
  80         /* Estimate total channel use caused by this frame */
  81
  82         if (unlikely(mode->num_rates < 0))
  83                 return TXRX_CONTINUE;
  84
  85         rate = &mode->rates[0];
  86         for (i = 0; i < mode->num_rates; i++) {
  87                 if (mode->rates[i].val == rx->u.rx.status->rate) {
  88                         rate = &mode->rates[i];
  89                         break;
  90                 }
  91         }
  92
  93         /* 1 bit at 1 Mbit/s takes 1 usec; in channel_use values,
  94          * 1 usec = 1/8 * (1080 / 10) = 13.5 */
  95
  96         if (mode->mode == MODE_IEEE80211A ||
  97             (mode->mode == MODE_IEEE80211G &&
  98              rate->flags & IEEE80211_RATE_ERP))
  99                 hdrtime = CHAN_UTIL_HDR_SHORT;
 100         else
 101                 hdrtime = CHAN_UTIL_HDR_LONG;
 102
 103         load = hdrtime;
 104         if (!is_multicast_ether_addr(hdr->addr1))
 105                 load += hdrtime;
 106
 107         load += skb->len * rate->rate_inv;
 108
 109         /* Divide channel_use by 8 to avoid wrapping around the counter */
 110         load >>= CHAN_UTIL_SHIFT;
 111         local->channel_use_raw += load;
 112         rx->u.rx.load = load;
 113
 114         return TXRX_CONTINUE;
 115 }
 116
 117 ieee80211_rx_handler ieee80211_rx_pre_handlers[] =
 118 {
 119         ieee80211_rx_h_parse_qos,
 120         ieee80211_rx_h_load_stats,
 121         NULL
 122 };
 123
 124 /* rx handlers */
 125
 126 static ieee80211_txrx_result
 127 ieee80211_rx_h_if_stats(struct ieee80211_txrx_data *rx)
 128 {
 129         if (rx->sta)
 130                 rx->sta->channel_use_raw += rx->u.rx.load;
 131         rx->sdata->channel_use_raw += rx->u.rx.load;
 132         return TXRX_CONTINUE;
 133 }
 134
 135 static void
 136 ieee80211_rx_monitor(struct net_device *dev, struct sk_buff *skb,
 137                      struct ieee80211_rx_status *status)
 138 {
 139         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 140         struct ieee80211_rate *rate;
 141         struct ieee80211_rtap_hdr {
 142                 struct ieee80211_radiotap_header hdr;
 143                 u8 flags;
 144                 u8 rate;
 145                 __le16 chan_freq;
 146                 __le16 chan_flags;
 147                 u8 antsignal;
 148         } __attribute__ ((packed)) *rthdr;
 149
 150         skb->dev = dev;
 151
 152         if (status->flag & RX_FLAG_RADIOTAP)
 153                 goto out;
 154
 155         if (skb_headroom(skb) < sizeof(*rthdr)) {
 156                 I802_DEBUG_INC(local->rx_expand_skb_head);
 157                 if (pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC)) {
 158                         dev_kfree_skb(skb);
 159                         return;
 160                 }
 161         }
 162
 163         rthdr = (struct ieee80211_rtap_hdr *) skb_push(skb, sizeof(*rthdr));
 164         memset(rthdr, 0, sizeof(*rthdr));
 165         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
 166         rthdr->hdr.it_present =
 167                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 168                             (1 << IEEE80211_RADIOTAP_RATE) |
 169                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
 170                             (1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL));
 171         rthdr->flags = local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS ?
 172                        IEEE80211_RADIOTAP_F_FCS : 0;
 173         rate = ieee80211_get_rate(local, status->phymode, status->rate);
 174         if (rate)
 175                 rthdr->rate = rate->rate / 5;
 176         rthdr->chan_freq = cpu_to_le16(status->freq);
 177         rthdr->chan_flags =
 178                 status->phymode == MODE_IEEE80211A ?
 179                 cpu_to_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ) :
 180                 cpu_to_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ);
 181         rthdr->antsignal = status->ssi;
 182
 183  out:
 184         dev->stats.rx_packets++;
 185         dev->stats.rx_bytes += skb->len;
 186
 187         skb_set_mac_header(skb, 0);
 188         skb->ip_summed = CHECKSUM_UNNECESSARY;
 189         skb->pkt_type = PACKET_OTHERHOST;
 190         skb->protocol = htons(ETH_P_802_2);
 191         memset(skb->cb, 0, sizeof(skb->cb));
 192         netif_rx(skb);
 193 }
 194
 195 static ieee80211_txrx_result
 196 ieee80211_rx_h_monitor(struct ieee80211_txrx_data *rx)
 197 {
 198         if (rx->sdata->type == IEEE80211_IF_TYPE_MNTR) {
 199                 ieee80211_rx_monitor(rx->dev, rx->skb, rx->u.rx.status);
 200                 return TXRX_QUEUED;
 201         }
 202
 203         if (rx->u.rx.status->flag & RX_FLAG_RADIOTAP)
 204                 skb_pull(rx->skb, ieee80211_get_radiotap_len(rx->skb->data));
 205
 206         return TXRX_CONTINUE;
 207 }
 208
 209 static ieee80211_txrx_result
 210 ieee80211_rx_h_passive_scan(struct ieee80211_txrx_data *rx)
 211 {
 212         struct ieee80211_local *local = rx->local;
 213         struct sk_buff *skb = rx->skb;
 214
 215         if (unlikely(local->sta_scanning != 0)) {
 216                 ieee80211_sta_rx_scan(rx->dev, skb, rx->u.rx.status);
 217                 return TXRX_QUEUED;
 218         }
 219
 220         if (unlikely(rx->flags & IEEE80211_TXRXD_RXIN_SCAN)) {
 221                 /* scanning finished during invoking of handlers */
 222                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
 223                 return TXRX_DROP;
 224         }
 225
 226         return TXRX_CONTINUE;
 227 }
 228
 229 static ieee80211_txrx_result
 230 ieee80211_rx_h_check(struct ieee80211_txrx_data *rx)
 231 {
 232         struct ieee80211_hdr *hdr;
 233         hdr = (struct ieee80211_hdr *) rx->skb->data;
 234
 235         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 236         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 237                 if (unlikely(rx->fc & IEEE80211_FCTL_RETRY &&
 238                              rx->sta->last_seq_ctrl[rx->u.rx.queue] ==
 239                              hdr->seq_ctrl)) {
 240                         if (rx->flags & IEEE80211_TXRXD_RXRA_MATCH) {
 241                                 rx->local->dot11FrameDuplicateCount++;
 242                                 rx->sta->num_duplicates++;
 243                         }
 244                         return TXRX_DROP;
 245                 } else
 246                         rx->sta->last_seq_ctrl[rx->u.rx.queue] = hdr->seq_ctrl;
 247         }
 248
 249         if ((rx->local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) &&
 250             rx->skb->len > FCS_LEN)
 251                 skb_trim(rx->skb, rx->skb->len - FCS_LEN);
 252
 253         if (unlikely(rx->skb->len < 16)) {
 254                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 255                 return TXRX_DROP;
 256         }
 257
 258         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 259                 rx->skb->pkt_type = PACKET_OTHERHOST;
 260         else if (compare_ether_addr(rx->dev->dev_addr, hdr->addr1) == 0)
 261                 rx->skb->pkt_type = PACKET_HOST;
 262         else if (is_multicast_ether_addr(hdr->addr1)) {
 263                 if (is_broadcast_ether_addr(hdr->addr1))
 264                         rx->skb->pkt_type = PACKET_BROADCAST;
 265                 else
 266                         rx->skb->pkt_type = PACKET_MULTICAST;
 267         } else
 268                 rx->skb->pkt_type = PACKET_OTHERHOST;
 269
 270         /* Drop disallowed frame classes based on STA auth/assoc state;
 271          * IEEE 802.11, Chap 5.5.
 272          *
 273          * 80211.o does filtering only based on association state, i.e., it
 274          * drops Class 3 frames from not associated stations. hostapd sends
 275          * deauth/disassoc frames when needed. In addition, hostapd is
 276          * responsible for filtering on both auth and assoc states.
 277          */
 278         if (unlikely(((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA ||
 279                       ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_CTL &&
 280                        (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PSPOLL)) &&
 281                      rx->sdata->type != IEEE80211_IF_TYPE_IBSS &&
 282                      (!rx->sta || !(rx->sta->flags & WLAN_STA_ASSOC)))) {
 283                 if ((!(rx->fc & IEEE80211_FCTL_FROMDS) &&
 284                      !(rx->fc & IEEE80211_FCTL_TODS) &&
 285                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA)
 286                     || !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
 287                         /* Drop IBSS frames and frames for other hosts
 288                          * silently. */
 289                         return TXRX_DROP;
 290                 }
 291
 292                 if (!rx->local->apdev)
 293                         return TXRX_DROP;
 294
 295                 ieee80211_rx_mgmt(rx->local, rx->skb, rx->u.rx.status,
 296                                   ieee80211_msg_sta_not_assoc);
 297                 return TXRX_QUEUED;
 298         }
 299
 300         return TXRX_CONTINUE;
 301 }
 302
 303
 304 static ieee80211_txrx_result
 305 ieee80211_rx_h_load_key(struct ieee80211_txrx_data *rx)
 306 {
 307         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 308         int keyidx;
 309         int hdrlen;
 310         struct ieee80211_key *stakey = NULL;
 311
 312         /*
 313          * Key selection 101
 314          *
 315          * There are three types of keys:
 316          *  - GTK (group keys)
 317          *  - PTK (pairwise keys)
 318          *  - STK (station-to-station pairwise keys)
 319          *
 320          * When selecting a key, we have to distinguish between multicast
 321          * (including broadcast) and unicast frames, the latter can only
 322          * use PTKs and STKs while the former always use GTKs. Unless, of
 323          * course, actual WEP keys ("pre-RSNA") are used, then unicast
 324          * frames can also use key indizes like GTKs. Hence, if we don't
 325          * have a PTK/STK we check the key index for a WEP key.
 326          *
 327          * Note that in a regular BSS, multicast frames are sent by the
 328          * AP only, associated stations unicast the frame to the AP first
 329          * which then multicasts it on their behalf.
 330          *
 331          * There is also a slight problem in IBSS mode: GTKs are negotiated
 332          * with each station, that is something we don't currently handle.
 333          * The spec seems to expect that one negotiates the same key with
 334          * every station but there's no such requirement; VLANs could be
 335          * possible.
 336          */
 337
 338         if (!(rx->fc & IEEE80211_FCTL_PROTECTED))
 339                 return TXRX_CONTINUE;
 340
 341         /*
 342          * No point in finding a key if the frame is neither
 343          * addressed to us nor a multicast frame.
 344          */
 345         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 346                 return TXRX_CONTINUE;
 347
 348         if (rx->sta)
 349                 stakey = rcu_dereference(rx->sta->key);
 350
 351         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
 352                 rx->key = stakey;
 353         } else {
 354                 /*
 355                  * The device doesn't give us the IV so we won't be
 356                  * able to look up the key. That's ok though, we
 357                  * don't need to decrypt the frame, we just won't
 358                  * be able to keep statistics accurate.
 359                  * Except for key threshold notifications, should
 360                  * we somehow allow the driver to tell us which key
 361                  * the hardware used if this flag is set?
 362                  */
 363                 if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) &&
 364                     (rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED))
 365                         return TXRX_CONTINUE;
 366
 367                 hdrlen = ieee80211_get_hdrlen(rx->fc);
 368
 369                 if (rx->skb->len < 8 + hdrlen)
 370                         return TXRX_DROP; /* TODO: count this? */
 371
 372                 /*
 373                  * no need to call ieee80211_wep_get_keyidx,
 374                  * it verifies a bunch of things we've done already
 375                  */
 376                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
 377
 378                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
 379
 380                 /*
 381                  * RSNA-protected unicast frames should always be sent with
 382                  * pairwise or station-to-station keys, but for WEP we allow
 383                  * using a key index as well.
 384                  */
 385                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
 386                     !is_multicast_ether_addr(hdr->addr1))
 387                         rx->key = NULL;
 388         }
 389
 390         if (rx->key) {
 391                 rx->key->tx_rx_count++;
 392                 if (unlikely(rx->local->key_tx_rx_threshold &&
 393                              rx->key->tx_rx_count >
 394                              rx->local->key_tx_rx_threshold)) {
 395                         ieee80211_key_threshold_notify(rx->dev, rx->key,
 396                                                        rx->sta);
 397                 }
 398         }
 399
 400         return TXRX_CONTINUE;
 401 }
 402
 403 static void ap_sta_ps_start(struct net_device *dev, struct sta_info *sta)
 404 {
 405         struct ieee80211_sub_if_data *sdata;
 406         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 407
 408         if (sdata->bss)
 409                 atomic_inc(&sdata->bss->num_sta_ps);
 410         sta->flags |= WLAN_STA_PS;
 411         sta->pspoll = 0;
 412 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 413         printk(KERN_DEBUG "%s: STA " MAC_FMT " aid %d enters power "
 414                "save mode\n", dev->name, MAC_ARG(sta->addr), sta->aid);
 415 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 416 }
 417
 418 static int ap_sta_ps_end(struct net_device *dev, struct sta_info *sta)
 419 {
 420         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 421         struct sk_buff *skb;
 422         int sent = 0;
 423         struct ieee80211_sub_if_data *sdata;
 424         struct ieee80211_tx_packet_data *pkt_data;
 425
 426         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 427         if (sdata->bss)
 428                 atomic_dec(&sdata->bss->num_sta_ps);
 429         sta->flags &= ~(WLAN_STA_PS | WLAN_STA_TIM);
 430         sta->pspoll = 0;
 431         if (!skb_queue_empty(&sta->ps_tx_buf)) {
 432                 if (local->ops->set_tim)
 433                         local->ops->set_tim(local_to_hw(local), sta->aid, 0);
 434                 if (sdata->bss)
 435                         bss_tim_clear(local, sdata->bss, sta->aid);
 436         }
 437 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 438         printk(KERN_DEBUG "%s: STA " MAC_FMT " aid %d exits power "
 439                "save mode\n", dev->name, MAC_ARG(sta->addr), sta->aid);
 440 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 441         /* Send all buffered frames to the station */
 442         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
 443                 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 444                 sent++;
 445                 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
 446                 dev_queue_xmit(skb);
 447         }
 448         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
 449                 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 450                 local->total_ps_buffered--;
 451                 sent++;
 452 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 453                 printk(KERN_DEBUG "%s: STA " MAC_FMT " aid %d send PS frame "
 454                        "since STA not sleeping anymore\n", dev->name,
 455                        MAC_ARG(sta->addr), sta->aid);
 456 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 457                 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
 458                 dev_queue_xmit(skb);
 459         }
 460
 461         return sent;
 462 }
 463
 464 static ieee80211_txrx_result
 465 ieee80211_rx_h_sta_process(struct ieee80211_txrx_data *rx)
 466 {
 467         struct sta_info *sta = rx->sta;
 468         struct net_device *dev = rx->dev;
 469         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 470
 471         if (!sta)
 472                 return TXRX_CONTINUE;
 473
 474         /* Update last_rx only for IBSS packets which are for the current
 475          * BSSID to avoid keeping the current IBSS network alive in cases where
 476          * other STAs are using different BSSID. */
 477         if (rx->sdata->type == IEEE80211_IF_TYPE_IBSS) {
 478                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len);
 479                 if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0)
 480                         sta->last_rx = jiffies;
 481         } else
 482         if (!is_multicast_ether_addr(hdr->addr1) ||
 483             rx->sdata->type == IEEE80211_IF_TYPE_STA) {
 484                 /* Update last_rx only for unicast frames in order to prevent
 485                  * the Probe Request frames (the only broadcast frames from a
 486                  * STA in infrastructure mode) from keeping a connection alive.
 487                  */
 488                 sta->last_rx = jiffies;
 489         }
 490
 491         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 492                 return TXRX_CONTINUE;
 493
 494         sta->rx_fragments++;
 495         sta->rx_bytes += rx->skb->len;
 496         sta->last_rssi = rx->u.rx.status->ssi;
 497         sta->last_signal = rx->u.rx.status->signal;
 498         sta->last_noise = rx->u.rx.status->noise;
 499
 500         if (!(rx->fc & IEEE80211_FCTL_MOREFRAGS)) {
 501                 /* Change STA power saving mode only in the end of a frame
 502                  * exchange sequence */
 503                 if ((sta->flags & WLAN_STA_PS) && !(rx->fc & IEEE80211_FCTL_PM))
 504                         rx->u.rx.sent_ps_buffered += ap_sta_ps_end(dev, sta);
 505                 else if (!(sta->flags & WLAN_STA_PS) &&
 506                          (rx->fc & IEEE80211_FCTL_PM))
 507                         ap_sta_ps_start(dev, sta);
 508         }
 509
 510         /* Drop data::nullfunc frames silently, since they are used only to
 511          * control station power saving mode. */
 512         if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 513             (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_NULLFUNC) {
 514                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
 515                 /* Update counter and free packet here to avoid counting this
 516                  * as a dropped packed. */
 517                 sta->rx_packets++;
 518                 dev_kfree_skb(rx->skb);
 519                 return TXRX_QUEUED;
 520         }
 521
 522         return TXRX_CONTINUE;
 523 } /* ieee80211_rx_h_sta_process */
 524
 525 static ieee80211_txrx_result
 526 ieee80211_rx_h_wep_weak_iv_detection(struct ieee80211_txrx_data *rx)
 527 {
 528         if (!rx->sta || !(rx->fc & IEEE80211_FCTL_PROTECTED) ||
 529             (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA ||
 530             !rx->key || rx->key->conf.alg != ALG_WEP ||
 531             !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 532                 return TXRX_CONTINUE;
 533
 534         /* Check for weak IVs, if hwaccel did not remove IV from the frame */
 535         if (!(rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED) ||
 536             !(rx->u.rx.status->flag & RX_FLAG_DECRYPTED))
 537                 if (ieee80211_wep_is_weak_iv(rx->skb, rx->key))
 538                         rx->sta->wep_weak_iv_count++;
 539
 540         return TXRX_CONTINUE;
 541 }
 542
 543 static ieee80211_txrx_result
 544 ieee80211_rx_h_wep_decrypt(struct ieee80211_txrx_data *rx)
 545 {
 546         if ((rx->key && rx->key->conf.alg != ALG_WEP) ||
 547             !(rx->fc & IEEE80211_FCTL_PROTECTED) ||
 548             ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
 549              ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
 550               (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)))
 551                 return TXRX_CONTINUE;
 552
 553         if (!rx->key) {
 554                 if (net_ratelimit())
 555                         printk(KERN_DEBUG "%s: RX WEP frame, but no key set\n",
 556                                rx->dev->name);
 557                 return TXRX_DROP;
 558         }
 559
 560         if (!(rx->u.rx.status->flag & RX_FLAG_DECRYPTED)) {
 561                 if (ieee80211_wep_decrypt(rx->local, rx->skb, rx->key)) {
 562                         if (net_ratelimit())
 563                                 printk(KERN_DEBUG "%s: RX WEP frame, decrypt "
 564                                        "failed\n", rx->dev->name);
 565                         return TXRX_DROP;
 566                 }
 567         } else if (!(rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED)) {
 568                 ieee80211_wep_remove_iv(rx->local, rx->skb, rx->key);
 569                 /* remove ICV */
 570                 skb_trim(rx->skb, rx->skb->len - 4);
 571         }
 572
 573         return TXRX_CONTINUE;
 574 }
 575
 576 static inline struct ieee80211_fragment_entry *
 577 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
 578                          unsigned int frag, unsigned int seq, int rx_queue,
 579                          struct sk_buff **skb)
 580 {
 581         struct ieee80211_fragment_entry *entry;
 582         int idx;
 583
 584         idx = sdata->fragment_next;
 585         entry = &sdata->fragments[sdata->fragment_next++];
 586         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
 587                 sdata->fragment_next = 0;
 588
 589         if (!skb_queue_empty(&entry->skb_list)) {
 590 #ifdef CONFIG_MAC80211_DEBUG
 591                 struct ieee80211_hdr *hdr =
 592                         (struct ieee80211_hdr *) entry->skb_list.next->data;
 593                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
 594                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
 595                        "addr1=" MAC_FMT " addr2=" MAC_FMT "\n",
 596                        sdata->dev->name, idx,
 597                        jiffies - entry->first_frag_time, entry->seq,
 598                        entry->last_frag, MAC_ARG(hdr->addr1),
 599                        MAC_ARG(hdr->addr2));
 600 #endif /* CONFIG_MAC80211_DEBUG */
 601                 __skb_queue_purge(&entry->skb_list);
 602         }
 603
 604         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
 605         *skb = NULL;
 606         entry->first_frag_time = jiffies;
 607         entry->seq = seq;
 608         entry->rx_queue = rx_queue;
 609         entry->last_frag = frag;
 610         entry->ccmp = 0;
 611         entry->extra_len = 0;
 612
 613         return entry;
 614 }
 615
 616 static inline struct ieee80211_fragment_entry *
 617 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
 618                           u16 fc, unsigned int frag, unsigned int seq,
 619                           int rx_queue, struct ieee80211_hdr *hdr)
 620 {
 621         struct ieee80211_fragment_entry *entry;
 622         int i, idx;
 623
 624         idx = sdata->fragment_next;
 625         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
 626                 struct ieee80211_hdr *f_hdr;
 627                 u16 f_fc;
 628
 629                 idx--;
 630                 if (idx < 0)
 631                         idx = IEEE80211_FRAGMENT_MAX - 1;
 632
 633                 entry = &sdata->fragments[idx];
 634                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
 635                     entry->rx_queue != rx_queue ||
 636                     entry->last_frag + 1 != frag)
 637                         continue;
 638
 639                 f_hdr = (struct ieee80211_hdr *) entry->skb_list.next->data;
 640                 f_fc = le16_to_cpu(f_hdr->frame_control);
 641
 642                 if ((fc & IEEE80211_FCTL_FTYPE) != (f_fc & IEEE80211_FCTL_FTYPE) ||
 643                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
 644                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
 645                         continue;
 646
 647                 if (entry->first_frag_time + 2 * HZ < jiffies) {
 648                         __skb_queue_purge(&entry->skb_list);
 649                         continue;
 650                 }
 651                 return entry;
 652         }
 653
 654         return NULL;
 655 }
 656
 657 static ieee80211_txrx_result
 658 ieee80211_rx_h_defragment(struct ieee80211_txrx_data *rx)
 659 {
 660         struct ieee80211_hdr *hdr;
 661         u16 sc;
 662         unsigned int frag, seq;
 663         struct ieee80211_fragment_entry *entry;
 664         struct sk_buff *skb;
 665
 666         hdr = (struct ieee80211_hdr *) rx->skb->data;
 667         sc = le16_to_cpu(hdr->seq_ctrl);
 668         frag = sc & IEEE80211_SCTL_FRAG;
 669
 670         if (likely((!(rx->fc & IEEE80211_FCTL_MOREFRAGS) && frag == 0) ||
 671                    (rx->skb)->len < 24 ||
 672                    is_multicast_ether_addr(hdr->addr1))) {
 673                 /* not fragmented */
 674                 goto out;
 675         }
 676         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
 677
 678         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
 679
 680         if (frag == 0) {
 681                 /* This is the first fragment of a new frame. */
 682                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
 683                                                  rx->u.rx.queue, &(rx->skb));
 684                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
 685                     (rx->fc & IEEE80211_FCTL_PROTECTED)) {
 686                         /* Store CCMP PN so that we can verify that the next
 687                          * fragment has a sequential PN value. */
 688                         entry->ccmp = 1;
 689                         memcpy(entry->last_pn,
 690                                rx->key->u.ccmp.rx_pn[rx->u.rx.queue],
 691                                CCMP_PN_LEN);
 692                 }
 693                 return TXRX_QUEUED;
 694         }
 695
 696         /* This is a fragment for a frame that should already be pending in
 697          * fragment cache. Add this fragment to the end of the pending entry.
 698          */
 699         entry = ieee80211_reassemble_find(rx->sdata, rx->fc, frag, seq,
 700                                           rx->u.rx.queue, hdr);
 701         if (!entry) {
 702                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 703                 return TXRX_DROP;
 704         }
 705
 706         /* Verify that MPDUs within one MSDU have sequential PN values.
 707          * (IEEE 802.11i, 8.3.3.4.5) */
 708         if (entry->ccmp) {
 709                 int i;
 710                 u8 pn[CCMP_PN_LEN], *rpn;
 711                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
 712                         return TXRX_DROP;
 713                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
 714                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
 715                         pn[i]++;
 716                         if (pn[i])
 717                                 break;
 718                 }
 719                 rpn = rx->key->u.ccmp.rx_pn[rx->u.rx.queue];
 720                 if (memcmp(pn, rpn, CCMP_PN_LEN) != 0) {
 721                         if (net_ratelimit())
 722                                 printk(KERN_DEBUG "%s: defrag: CCMP PN not "
 723                                        "sequential A2=" MAC_FMT
 724                                        " PN=%02x%02x%02x%02x%02x%02x "
 725                                        "(expected %02x%02x%02x%02x%02x%02x)\n",
 726                                        rx->dev->name, MAC_ARG(hdr->addr2),
 727                                        rpn[0], rpn[1], rpn[2], rpn[3], rpn[4],
 728                                        rpn[5], pn[0], pn[1], pn[2], pn[3],
 729                                        pn[4], pn[5]);
 730                         return TXRX_DROP;
 731                 }
 732                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
 733         }
 734
 735         skb_pull(rx->skb, ieee80211_get_hdrlen(rx->fc));
 736         __skb_queue_tail(&entry->skb_list, rx->skb);
 737         entry->last_frag = frag;
 738         entry->extra_len += rx->skb->len;
 739         if (rx->fc & IEEE80211_FCTL_MOREFRAGS) {
 740                 rx->skb = NULL;
 741                 return TXRX_QUEUED;
 742         }
 743
 744         rx->skb = __skb_dequeue(&entry->skb_list);
 745         if (skb_tailroom(rx->skb) < entry->extra_len) {
 746                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
 747                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
 748                                               GFP_ATOMIC))) {
 749                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 750                         __skb_queue_purge(&entry->skb_list);
 751                         return TXRX_DROP;
 752                 }
 753         }
 754         while ((skb = __skb_dequeue(&entry->skb_list))) {
 755                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
 756                 dev_kfree_skb(skb);
 757         }
 758
 759         /* Complete frame has been reassembled - process it now */
 760         rx->flags |= IEEE80211_TXRXD_FRAGMENTED;
 761
 762  out:
 763         if (rx->sta)
 764                 rx->sta->rx_packets++;
 765         if (is_multicast_ether_addr(hdr->addr1))
 766                 rx->local->dot11MulticastReceivedFrameCount++;
 767         else
 768                 ieee80211_led_rx(rx->local);
 769         return TXRX_CONTINUE;
 770 }
 771
 772 static ieee80211_txrx_result
 773 ieee80211_rx_h_ps_poll(struct ieee80211_txrx_data *rx)
 774 {
 775         struct sk_buff *skb;
 776         int no_pending_pkts;
 777
 778         if (likely(!rx->sta ||
 779                    (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL ||
 780                    (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PSPOLL ||
 781                    !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)))
 782                 return TXRX_CONTINUE;
 783
 784         skb = skb_dequeue(&rx->sta->tx_filtered);
 785         if (!skb) {
 786                 skb = skb_dequeue(&rx->sta->ps_tx_buf);
 787                 if (skb)
 788                         rx->local->total_ps_buffered--;
 789         }
 790         no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
 791                 skb_queue_empty(&rx->sta->ps_tx_buf);
 792
 793         if (skb) {
 794                 struct ieee80211_hdr *hdr =
 795                         (struct ieee80211_hdr *) skb->data;
 796
 797                 /* tell TX path to send one frame even though the STA may
 798                  * still remain is PS mode after this frame exchange */
 799                 rx->sta->pspoll = 1;
 800
 801 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 802                 printk(KERN_DEBUG "STA " MAC_FMT " aid %d: PS Poll (entries "
 803                        "after %d)\n",
 804                        MAC_ARG(rx->sta->addr), rx->sta->aid,
 805                        skb_queue_len(&rx->sta->ps_tx_buf));
 806 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 807
 808                 /* Use MoreData flag to indicate whether there are more
 809                  * buffered frames for this STA */
 810                 if (no_pending_pkts) {
 811                         hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
 812                         rx->sta->flags &= ~WLAN_STA_TIM;
 813                 } else
 814                         hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
 815
 816                 dev_queue_xmit(skb);
 817
 818                 if (no_pending_pkts) {
 819                         if (rx->local->ops->set_tim)
 820                                 rx->local->ops->set_tim(local_to_hw(rx->local),
 821                                                        rx->sta->aid, 0);
 822                         if (rx->sdata->bss)
 823                                 bss_tim_clear(rx->local, rx->sdata->bss, rx->sta->aid);
 824                 }
 825 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 826         } else if (!rx->u.rx.sent_ps_buffered) {
 827                 printk(KERN_DEBUG "%s: STA " MAC_FMT " sent PS Poll even "
 828                        "though there is no buffered frames for it\n",
 829                        rx->dev->name, MAC_ARG(rx->sta->addr));
 830 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 831
 832         }
 833
 834         /* Free PS Poll skb here instead of returning TXRX_DROP that would
 835          * count as an dropped frame. */
 836         dev_kfree_skb(rx->skb);
 837
 838         return TXRX_QUEUED;
 839 }
 840
 841 static ieee80211_txrx_result
 842 ieee80211_rx_h_remove_qos_control(struct ieee80211_txrx_data *rx)
 843 {
 844         u16 fc = rx->fc;
 845         u8 *data = rx->skb->data;
 846         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) data;
 847
 848         if (!WLAN_FC_IS_QOS_DATA(fc))
 849                 return TXRX_CONTINUE;
 850
 851         /* remove the qos control field, update frame type and meta-data */
 852         memmove(data + 2, data, ieee80211_get_hdrlen(fc) - 2);
 853         hdr = (struct ieee80211_hdr *) skb_pull(rx->skb, 2);
 854         /* change frame type to non QOS */
 855         rx->fc = fc &= ~IEEE80211_STYPE_QOS_DATA;
 856         hdr->frame_control = cpu_to_le16(fc);
 857
 858         return TXRX_CONTINUE;
 859 }
 860
 861 static ieee80211_txrx_result
 862 ieee80211_rx_h_802_1x_pae(struct ieee80211_txrx_data *rx)
 863 {
 864         if (rx->sdata->eapol && ieee80211_is_eapol(rx->skb) &&
 865             rx->sdata->type != IEEE80211_IF_TYPE_STA &&
 866             (rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
 867                 /* Pass both encrypted and unencrypted EAPOL frames to user
 868                  * space for processing. */
 869                 if (!rx->local->apdev)
 870                         return TXRX_DROP;
 871                 ieee80211_rx_mgmt(rx->local, rx->skb, rx->u.rx.status,
 872                                   ieee80211_msg_normal);
 873                 return TXRX_QUEUED;
 874         }
 875
 876         if (unlikely(rx->sdata->ieee802_1x &&
 877                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 878                      (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
 879                      (!rx->sta || !(rx->sta->flags & WLAN_STA_AUTHORIZED)) &&
 880                      !ieee80211_is_eapol(rx->skb))) {
 881 #ifdef CONFIG_MAC80211_DEBUG
 882                 struct ieee80211_hdr *hdr =
 883                         (struct ieee80211_hdr *) rx->skb->data;
 884                 printk(KERN_DEBUG "%s: dropped frame from " MAC_FMT
 885                        " (unauthorized port)\n", rx->dev->name,
 886                        MAC_ARG(hdr->addr2));
 887 #endif /* CONFIG_MAC80211_DEBUG */
 888                 return TXRX_DROP;
 889         }
 890
 891         return TXRX_CONTINUE;
 892 }
 893
 894 static ieee80211_txrx_result
 895 ieee80211_rx_h_drop_unencrypted(struct ieee80211_txrx_data *rx)
 896 {
 897         /*
 898          * Pass through unencrypted frames if the hardware has
 899          * decrypted them already.
 900          */
 901         if (rx->u.rx.status->flag & RX_FLAG_DECRYPTED)
 902                 return TXRX_CONTINUE;
 903
 904         /* Drop unencrypted frames if key is set. */
 905         if (unlikely(!(rx->fc & IEEE80211_FCTL_PROTECTED) &&
 906                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 907                      (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
 908                      (rx->key || rx->sdata->drop_unencrypted) &&
 909                      (rx->sdata->eapol == 0 ||
 910                       !ieee80211_is_eapol(rx->skb)))) {
 911                 if (net_ratelimit())
 912                         printk(KERN_DEBUG "%s: RX non-WEP frame, but expected "
 913                                "encryption\n", rx->dev->name);
 914                 return TXRX_DROP;
 915         }
 916         return TXRX_CONTINUE;
 917 }
 918
 919 static ieee80211_txrx_result
 920 ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
 921 {
 922         struct net_device *dev = rx->dev;
 923         struct ieee80211_local *local = rx->local;
 924         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 925         u16 fc, hdrlen, ethertype;
 926         u8 *payload;
 927         u8 dst[ETH_ALEN];
 928         u8 src[ETH_ALEN];
 929         struct sk_buff *skb = rx->skb, *skb2;
 930         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 931
 932         fc = rx->fc;
 933         if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
 934                 return TXRX_CONTINUE;
 935
 936         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
 937                 return TXRX_DROP;
 938
 939         hdrlen = ieee80211_get_hdrlen(fc);
 940
 941         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
 942          * header
 943          * IEEE 802.11 address fields:
 944          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
 945          *   0     0   DA    SA    BSSID n/a
 946          *   0     1   DA    BSSID SA    n/a
 947          *   1     0   BSSID SA    DA    n/a
 948          *   1     1   RA    TA    DA    SA
 949          */
 950
 951         switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
 952         case IEEE80211_FCTL_TODS:
 953                 /* BSSID SA DA */
 954                 memcpy(dst, hdr->addr3, ETH_ALEN);
 955                 memcpy(src, hdr->addr2, ETH_ALEN);
 956
 957                 if (unlikely(sdata->type != IEEE80211_IF_TYPE_AP &&
 958                              sdata->type != IEEE80211_IF_TYPE_VLAN)) {
 959                         if (net_ratelimit())
 960                                 printk(KERN_DEBUG "%s: dropped ToDS frame "
 961                                        "(BSSID=" MAC_FMT
 962                                        " SA=" MAC_FMT
 963                                        " DA=" MAC_FMT ")\n",
 964                                        dev->name,
 965                                        MAC_ARG(hdr->addr1),
 966                                        MAC_ARG(hdr->addr2),
 967                                        MAC_ARG(hdr->addr3));
 968                         return TXRX_DROP;
 969                 }
 970                 break;
 971         case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
 972                 /* RA TA DA SA */
 973                 memcpy(dst, hdr->addr3, ETH_ALEN);
 974                 memcpy(src, hdr->addr4, ETH_ALEN);
 975
 976                 if (unlikely(sdata->type != IEEE80211_IF_TYPE_WDS)) {
 977                         if (net_ratelimit())
 978                                 printk(KERN_DEBUG "%s: dropped FromDS&ToDS "
 979                                        "frame (RA=" MAC_FMT
 980                                        " TA=" MAC_FMT " DA=" MAC_FMT
 981                                        " SA=" MAC_FMT ")\n",
 982                                        rx->dev->name,
 983                                        MAC_ARG(hdr->addr1),
 984                                        MAC_ARG(hdr->addr2),
 985                                        MAC_ARG(hdr->addr3),
 986                                        MAC_ARG(hdr->addr4));
 987                         return TXRX_DROP;
 988                 }
 989                 break;
 990         case IEEE80211_FCTL_FROMDS:
 991                 /* DA BSSID SA */
 992                 memcpy(dst, hdr->addr1, ETH_ALEN);
 993                 memcpy(src, hdr->addr3, ETH_ALEN);
 994
 995                 if (sdata->type != IEEE80211_IF_TYPE_STA ||
 996                     (is_multicast_ether_addr(dst) &&
 997                      !compare_ether_addr(src, dev->dev_addr)))
 998                         return TXRX_DROP;
 999                 break;
1000         case 0:
1001                 /* DA SA BSSID */
1002                 memcpy(dst, hdr->addr1, ETH_ALEN);
1003                 memcpy(src, hdr->addr2, ETH_ALEN);
1004
1005                 if (sdata->type != IEEE80211_IF_TYPE_IBSS) {
1006                         if (net_ratelimit()) {
1007                                 printk(KERN_DEBUG "%s: dropped IBSS frame (DA="
1008                                        MAC_FMT " SA=" MAC_FMT " BSSID=" MAC_FMT
1009                                        ")\n",
1010                                        dev->name, MAC_ARG(hdr->addr1),
1011                                        MAC_ARG(hdr->addr2),
1012                                        MAC_ARG(hdr->addr3));
1013                         }
1014                         return TXRX_DROP;
1015                 }
1016                 break;
1017         }
1018
1019         payload = skb->data + hdrlen;
1020
1021         if (unlikely(skb->len - hdrlen < 8)) {
1022                 if (net_ratelimit()) {
1023                         printk(KERN_DEBUG "%s: RX too short data frame "
1024                                "payload\n", dev->name);
1025                 }
1026                 return TXRX_DROP;
1027         }
1028
1029         ethertype = (payload[6] << 8) | payload[7];
1030
1031         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1032                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1033                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1034                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1035                  * replace EtherType */
1036                 skb_pull(skb, hdrlen + 6);
1037                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1038                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1039         } else {
1040                 struct ethhdr *ehdr;
1041                 __be16 len;
1042                 skb_pull(skb, hdrlen);
1043                 len = htons(skb->len);
1044                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1045                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1046                 memcpy(ehdr->h_source, src, ETH_ALEN);
1047                 ehdr->h_proto = len;
1048         }
1049         skb->dev = dev;
1050
1051         skb2 = NULL;
1052
1053         dev->stats.rx_packets++;
1054         dev->stats.rx_bytes += skb->len;
1055
1056         if (local->bridge_packets && (sdata->type == IEEE80211_IF_TYPE_AP
1057             || sdata->type == IEEE80211_IF_TYPE_VLAN) &&
1058             (rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
1059                 if (is_multicast_ether_addr(skb->data)) {
1060                         /* send multicast frames both to higher layers in
1061                          * local net stack and back to the wireless media */
1062                         skb2 = skb_copy(skb, GFP_ATOMIC);
1063                         if (!skb2 && net_ratelimit())
1064                                 printk(KERN_DEBUG "%s: failed to clone "
1065                                        "multicast frame\n", dev->name);
1066                 } else {
1067                         struct sta_info *dsta;
1068                         dsta = sta_info_get(local, skb->data);
1069                         if (dsta && !dsta->dev) {
1070                                 if (net_ratelimit())
1071                                         printk(KERN_DEBUG "Station with null "
1072                                                "dev structure!\n");
1073                         } else if (dsta && dsta->dev == dev) {
1074                                 /* Destination station is associated to this
1075                                  * AP, so send the frame directly to it and
1076                                  * do not pass the frame to local net stack.
1077                                  */
1078                                 skb2 = skb;
1079                                 skb = NULL;
1080                         }
1081                         if (dsta)
1082                                 sta_info_put(dsta);
1083                 }
1084         }
1085
1086         if (skb) {
1087                 /* deliver to local stack */
1088                 skb->protocol = eth_type_trans(skb, dev);
1089                 memset(skb->cb, 0, sizeof(skb->cb));
1090                 netif_rx(skb);
1091         }
1092
1093         if (skb2) {
1094                 /* send to wireless media */
1095                 skb2->protocol = __constant_htons(ETH_P_802_3);
1096                 skb_set_network_header(skb2, 0);
1097                 skb_set_mac_header(skb2, 0);
1098                 dev_queue_xmit(skb2);
1099         }
1100
1101         return TXRX_QUEUED;
1102 }
1103
1104 static ieee80211_txrx_result
1105 ieee80211_rx_h_mgmt(struct ieee80211_txrx_data *rx)
1106 {
1107         struct ieee80211_sub_if_data *sdata;
1108
1109         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
1110                 return TXRX_DROP;
1111
1112         sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1113         if ((sdata->type == IEEE80211_IF_TYPE_STA ||
1114              sdata->type == IEEE80211_IF_TYPE_IBSS) &&
1115             !rx->local->user_space_mlme) {
1116                 ieee80211_sta_rx_mgmt(rx->dev, rx->skb, rx->u.rx.status);
1117         } else {
1118                 /* Management frames are sent to hostapd for processing */
1119                 if (!rx->local->apdev)
1120                         return TXRX_DROP;
1121                 ieee80211_rx_mgmt(rx->local, rx->skb, rx->u.rx.status,
1122                                   ieee80211_msg_normal);
1123         }
1124         return TXRX_QUEUED;
1125 }
1126
1127 static inline ieee80211_txrx_result __ieee80211_invoke_rx_handlers(
1128                                 struct ieee80211_local *local,
1129                                 ieee80211_rx_handler *handlers,
1130                                 struct ieee80211_txrx_data *rx,
1131                                 struct sta_info *sta)
1132 {
1133         ieee80211_rx_handler *handler;
1134         ieee80211_txrx_result res = TXRX_DROP;
1135
1136         for (handler = handlers; *handler != NULL; handler++) {
1137                 res = (*handler)(rx);
1138
1139                 switch (res) {
1140                 case TXRX_CONTINUE:
1141                         continue;
1142                 case TXRX_DROP:
1143                         I802_DEBUG_INC(local->rx_handlers_drop);
1144                         if (sta)
1145                                 sta->rx_dropped++;
1146                         break;
1147                 case TXRX_QUEUED:
1148                         I802_DEBUG_INC(local->rx_handlers_queued);
1149                         break;
1150                 }
1151                 break;
1152         }
1153
1154         if (res == TXRX_DROP)
1155                 dev_kfree_skb(rx->skb);
1156         return res;
1157 }
1158
1159 static inline void ieee80211_invoke_rx_handlers(struct ieee80211_local *local,
1160                                                 ieee80211_rx_handler *handlers,
1161                                                 struct ieee80211_txrx_data *rx,
1162                                                 struct sta_info *sta)
1163 {
1164         if (__ieee80211_invoke_rx_handlers(local, handlers, rx, sta) ==
1165             TXRX_CONTINUE)
1166                 dev_kfree_skb(rx->skb);
1167 }
1168
1169 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1170                                             struct ieee80211_hdr *hdr,
1171                                             struct sta_info *sta,
1172                                             struct ieee80211_txrx_data *rx)
1173 {
1174         int keyidx, hdrlen;
1175
1176         hdrlen = ieee80211_get_hdrlen_from_skb(rx->skb);
1177         if (rx->skb->len >= hdrlen + 4)
1178                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1179         else
1180                 keyidx = -1;
1181
1182         if (net_ratelimit())
1183                 printk(KERN_DEBUG "%s: TKIP hwaccel reported Michael MIC "
1184                        "failure from " MAC_FMT " to " MAC_FMT " keyidx=%d\n",
1185                        dev->name, MAC_ARG(hdr->addr2), MAC_ARG(hdr->addr1),
1186                        keyidx);
1187
1188         if (!sta) {
1189                 /*
1190                  * Some hardware seem to generate incorrect Michael MIC
1191                  * reports; ignore them to avoid triggering countermeasures.
1192                  */
1193                 if (net_ratelimit())
1194                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1195                                "error for unknown address " MAC_FMT "\n",
1196                                dev->name, MAC_ARG(hdr->addr2));
1197                 goto ignore;
1198         }
1199
1200         if (!(rx->fc & IEEE80211_FCTL_PROTECTED)) {
1201                 if (net_ratelimit())
1202                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1203                                "error for a frame with no PROTECTED flag (src "
1204                                MAC_FMT ")\n", dev->name, MAC_ARG(hdr->addr2));
1205                 goto ignore;
1206         }
1207
1208         if (rx->sdata->type == IEEE80211_IF_TYPE_AP && keyidx) {
1209                 /*
1210                  * APs with pairwise keys should never receive Michael MIC
1211                  * errors for non-zero keyidx because these are reserved for
1212                  * group keys and only the AP is sending real multicast
1213                  * frames in the BSS.
1214                  */
1215                 if (net_ratelimit())
1216                         printk(KERN_DEBUG "%s: ignored Michael MIC error for "
1217                                "a frame with non-zero keyidx (%d)"
1218                                " (src " MAC_FMT ")\n", dev->name, keyidx,
1219                                MAC_ARG(hdr->addr2));
1220                 goto ignore;
1221         }
1222
1223         if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
1224             ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
1225              (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)) {
1226                 if (net_ratelimit())
1227                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1228                                "error for a frame that cannot be encrypted "
1229                                "(fc=0x%04x) (src " MAC_FMT ")\n",
1230                                dev->name, rx->fc, MAC_ARG(hdr->addr2));
1231                 goto ignore;
1232         }
1233
1234         mac80211_ev_michael_mic_failure(rx->dev, keyidx, hdr);
1235  ignore:
1236         dev_kfree_skb(rx->skb);
1237         rx->skb = NULL;
1238 }
1239
1240 ieee80211_rx_handler ieee80211_rx_handlers[] =
1241 {
1242         ieee80211_rx_h_if_stats,
1243         ieee80211_rx_h_monitor,
1244         ieee80211_rx_h_passive_scan,
1245         ieee80211_rx_h_check,
1246         ieee80211_rx_h_load_key,
1247         ieee80211_rx_h_sta_process,
1248         ieee80211_rx_h_ccmp_decrypt,
1249         ieee80211_rx_h_tkip_decrypt,
1250         ieee80211_rx_h_wep_weak_iv_detection,
1251         ieee80211_rx_h_wep_decrypt,
1252         ieee80211_rx_h_defragment,
1253         ieee80211_rx_h_ps_poll,
1254         ieee80211_rx_h_michael_mic_verify,
1255         /* this must be after decryption - so header is counted in MPDU mic
1256          * must be before pae and data, so QOS_DATA format frames
1257          * are not passed to user space by these functions
1258          */
1259         ieee80211_rx_h_remove_qos_control,
1260         ieee80211_rx_h_802_1x_pae,
1261         ieee80211_rx_h_drop_unencrypted,
1262         ieee80211_rx_h_data,
1263         ieee80211_rx_h_mgmt,
1264         NULL
1265 };
1266
1267 /* main receive path */
1268
1269 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
1270                                 u8 *bssid, struct ieee80211_txrx_data *rx,
1271                                 struct ieee80211_hdr *hdr)
1272 {
1273         int multicast = is_multicast_ether_addr(hdr->addr1);
1274
1275         switch (sdata->type) {
1276         case IEEE80211_IF_TYPE_STA:
1277                 if (!bssid)
1278                         return 0;
1279                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1280                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1281                                 return 0;
1282                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1283                 } else if (!multicast &&
1284                            compare_ether_addr(sdata->dev->dev_addr,
1285                                               hdr->addr1) != 0) {
1286                         if (!(sdata->flags & IEEE80211_SDATA_PROMISC))
1287                                 return 0;
1288                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1289                 }
1290                 break;
1291         case IEEE80211_IF_TYPE_IBSS:
1292                 if (!bssid)
1293                         return 0;
1294                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1295                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1296                                 return 0;
1297                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1298                 } else if (!multicast &&
1299                            compare_ether_addr(sdata->dev->dev_addr,
1300                                               hdr->addr1) != 0) {
1301                         if (!(sdata->flags & IEEE80211_SDATA_PROMISC))
1302                                 return 0;
1303                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1304                 } else if (!rx->sta)
1305                         rx->sta = ieee80211_ibss_add_sta(sdata->dev, rx->skb,
1306                                                          bssid, hdr->addr2);
1307                 break;
1308         case IEEE80211_IF_TYPE_AP:
1309                 if (!bssid) {
1310                         if (compare_ether_addr(sdata->dev->dev_addr,
1311                                                hdr->addr1))
1312                                 return 0;
1313                 } else if (!ieee80211_bssid_match(bssid,
1314                                         sdata->dev->dev_addr)) {
1315                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1316                                 return 0;
1317                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1318                 }
1319                 if (sdata->dev == sdata->local->mdev &&
1320                     !(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1321                         /* do not receive anything via
1322                          * master device when not scanning */
1323                         return 0;
1324                 break;
1325         case IEEE80211_IF_TYPE_WDS:
1326                 if (bssid ||
1327                     (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
1328                         return 0;
1329                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
1330                         return 0;
1331                 break;
1332         }
1333
1334         return 1;
1335 }
1336
1337 /*
1338  * This is the receive path handler. It is called by a low level driver when an
1339  * 802.11 MPDU is received from the hardware.
1340  */
1341 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
1342                     struct ieee80211_rx_status *status)
1343 {
1344         struct ieee80211_local *local = hw_to_local(hw);
1345         struct ieee80211_sub_if_data *sdata;
1346         struct sta_info *sta;
1347         struct ieee80211_hdr *hdr;
1348         struct ieee80211_txrx_data rx;
1349         u16 type;
1350         int radiotap_len = 0, prepres;
1351         struct ieee80211_sub_if_data *prev = NULL;
1352         struct sk_buff *skb_new;
1353         u8 *bssid;
1354
1355         if (status->flag & RX_FLAG_RADIOTAP) {
1356                 radiotap_len = ieee80211_get_radiotap_len(skb->data);
1357                 skb_pull(skb, radiotap_len);
1358         }
1359
1360         /*
1361          * key references are protected using RCU and this requires that
1362          * we are in a read-site RCU section during receive processing
1363          */
1364         rcu_read_lock();
1365
1366         hdr = (struct ieee80211_hdr *) skb->data;
1367         memset(&rx, 0, sizeof(rx));
1368         rx.skb = skb;
1369         rx.local = local;
1370
1371         rx.u.rx.status = status;
1372         rx.fc = skb->len >= 2 ? le16_to_cpu(hdr->frame_control) : 0;
1373         type = rx.fc & IEEE80211_FCTL_FTYPE;
1374         if (type == IEEE80211_FTYPE_DATA || type == IEEE80211_FTYPE_MGMT)
1375                 local->dot11ReceivedFragmentCount++;
1376
1377         if (skb->len >= 16) {
1378                 sta = rx.sta = sta_info_get(local, hdr->addr2);
1379                 if (sta) {
1380                         rx.dev = rx.sta->dev;
1381                         rx.sdata = IEEE80211_DEV_TO_SUB_IF(rx.dev);
1382                 }
1383         } else
1384                 sta = rx.sta = NULL;
1385
1386         if ((status->flag & RX_FLAG_MMIC_ERROR)) {
1387                 ieee80211_rx_michael_mic_report(local->mdev, hdr, sta, &rx);
1388                 goto end;
1389         }
1390
1391         if (unlikely(local->sta_scanning))
1392                 rx.flags |= IEEE80211_TXRXD_RXIN_SCAN;
1393
1394         if (__ieee80211_invoke_rx_handlers(local, local->rx_pre_handlers, &rx,
1395                                            sta) != TXRX_CONTINUE)
1396                 goto end;
1397         skb = rx.skb;
1398
1399         skb_push(skb, radiotap_len);
1400         if (sta && !(sta->flags & (WLAN_STA_WDS | WLAN_STA_ASSOC_AP)) &&
1401             !local->iff_promiscs && !is_multicast_ether_addr(hdr->addr1)) {
1402                 rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
1403                 ieee80211_invoke_rx_handlers(local, local->rx_handlers, &rx,
1404                                              rx.sta);
1405                 sta_info_put(sta);
1406                 rcu_read_unlock();
1407                 return;
1408         }
1409
1410         bssid = ieee80211_get_bssid(hdr, skb->len - radiotap_len);
1411
1412         read_lock(&local->sub_if_lock);
1413         list_for_each_entry(sdata, &local->sub_if_list, list) {
1414                 rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
1415
1416                 if (!netif_running(sdata->dev))
1417                         continue;
1418
1419                 prepres = prepare_for_handlers(sdata, bssid, &rx, hdr);
1420                 /* prepare_for_handlers can change sta */
1421                 sta = rx.sta;
1422
1423                 if (!prepres)
1424                         continue;
1425
1426                 /*
1427                  * frame is destined for this interface, but if it's not
1428                  * also for the previous one we handle that after the
1429                  * loop to avoid copying the SKB once too much
1430                  */
1431
1432                 if (!prev) {
1433                         prev = sdata;
1434                         continue;
1435                 }
1436
1437                 /*
1438                  * frame was destined for the previous interface
1439                  * so invoke RX handlers for it
1440                  */
1441
1442                 skb_new = skb_copy(skb, GFP_ATOMIC);
1443                 if (!skb_new) {
1444                         if (net_ratelimit())
1445                                 printk(KERN_DEBUG "%s: failed to copy "
1446                                        "multicast frame for %s",
1447                                        local->mdev->name, prev->dev->name);
1448                         continue;
1449                 }
1450                 rx.skb = skb_new;
1451                 rx.dev = prev->dev;
1452                 rx.sdata = prev;
1453                 ieee80211_invoke_rx_handlers(local, local->rx_handlers,
1454                                              &rx, sta);
1455                 prev = sdata;
1456         }
1457         if (prev) {
1458                 rx.skb = skb;
1459                 rx.dev = prev->dev;
1460                 rx.sdata = prev;
1461                 ieee80211_invoke_rx_handlers(local, local->rx_handlers,
1462                                              &rx, sta);
1463         } else
1464                 dev_kfree_skb(skb);
1465         read_unlock(&local->sub_if_lock);
1466
1467  end:
1468         rcu_read_unlock();
1469
1470         if (sta)
1471                 sta_info_put(sta);
1472 }
1473 EXPORT_SYMBOL(__ieee80211_rx);
1474
1475 /* This is a version of the rx handler that can be called from hard irq
1476  * context. Post the skb on the queue and schedule the tasklet */
1477 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
1478                           struct ieee80211_rx_status *status)
1479 {
1480         struct ieee80211_local *local = hw_to_local(hw);
1481
1482         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
1483
1484         skb->dev = local->mdev;
1485         /* copy status into skb->cb for use by tasklet */
1486         memcpy(skb->cb, status, sizeof(*status));
1487         skb->pkt_type = IEEE80211_RX_MSG;
1488         skb_queue_tail(&local->skb_queue, skb);
1489         tasklet_schedule(&local->tasklet);
1490 }
1491 EXPORT_SYMBOL(ieee80211_rx_irqsafe);