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 <net/mac80211.h>
  17 #include <net/ieee80211_radiotap.h>
  18
  19 #include "ieee80211_i.h"
  20 #include "ieee80211_led.h"
  21 #include "ieee80211_common.h"
  22 #include "wep.h"
  23 #include "wpa.h"
  24 #include "tkip.h"
  25 #include "wme.h"
  26
  27 /* pre-rx handlers
  28  *
  29  * these don't have dev/sdata fields in the rx data
  30  * The sta value should also not be used because it may
  31  * be NULL even though a STA (in IBSS mode) will be added.
  32  */
  33
  34 static ieee80211_txrx_result
  35 ieee80211_rx_h_parse_qos(struct ieee80211_txrx_data *rx)
  36 {
  37         u8 *data = rx->skb->data;
  38         int tid;
  39
  40         /* does the frame have a qos control field? */
  41         if (WLAN_FC_IS_QOS_DATA(rx->fc)) {
  42                 u8 *qc = data + ieee80211_get_hdrlen(rx->fc) - QOS_CONTROL_LEN;
  43                 /* frame has qos control */
  44                 tid = qc[0] & QOS_CONTROL_TID_MASK;
  45         } else {
  46                 if (unlikely((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT)) {
  47                         /* Separate TID for management frames */
  48                         tid = NUM_RX_DATA_QUEUES - 1;
  49                 } else {
  50                         /* no qos control present */
  51                         tid = 0; /* 802.1d - Best Effort */
  52                 }
  53         }
  54
  55         I802_DEBUG_INC(rx->local->wme_rx_queue[tid]);
  56         /* only a debug counter, sta might not be assigned properly yet */
  57         if (rx->sta)
  58                 I802_DEBUG_INC(rx->sta->wme_rx_queue[tid]);
  59
  60         rx->u.rx.queue = tid;
  61         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
  62          * For now, set skb->priority to 0 for other cases. */
  63         rx->skb->priority = (tid > 7) ? 0 : tid;
  64
  65         return TXRX_CONTINUE;
  66 }
  67
  68 static ieee80211_txrx_result
  69 ieee80211_rx_h_load_stats(struct ieee80211_txrx_data *rx)
  70 {
  71         struct ieee80211_local *local = rx->local;
  72         struct sk_buff *skb = rx->skb;
  73         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
  74         u32 load = 0, hdrtime;
  75         struct ieee80211_rate *rate;
  76         struct ieee80211_hw_mode *mode = local->hw.conf.mode;
  77         int i;
  78
  79         /* Estimate total channel use caused by this frame */
  80
  81         if (unlikely(mode->num_rates < 0))
  82                 return TXRX_CONTINUE;
  83
  84         rate = &mode->rates[0];
  85         for (i = 0; i < mode->num_rates; i++) {
  86                 if (mode->rates[i].val == rx->u.rx.status->rate) {
  87                         rate = &mode->rates[i];
  88                         break;
  89                 }
  90         }
  91
  92         /* 1 bit at 1 Mbit/s takes 1 usec; in channel_use values,
  93          * 1 usec = 1/8 * (1080 / 10) = 13.5 */
  94
  95         if (mode->mode == MODE_IEEE80211A ||
  96             mode->mode == MODE_ATHEROS_TURBO ||
  97             mode->mode == MODE_ATHEROS_TURBOG ||
  98             (mode->mode == MODE_IEEE80211G &&
  99              rate->flags & IEEE80211_RATE_ERP))
 100                 hdrtime = CHAN_UTIL_HDR_SHORT;
 101         else
 102                 hdrtime = CHAN_UTIL_HDR_LONG;
 103
 104         load = hdrtime;
 105         if (!is_multicast_ether_addr(hdr->addr1))
 106                 load += hdrtime;
 107
 108         load += skb->len * rate->rate_inv;
 109
 110         /* Divide channel_use by 8 to avoid wrapping around the counter */
 111         load >>= CHAN_UTIL_SHIFT;
 112         local->channel_use_raw += load;
 113         rx->u.rx.load = load;
 114
 115         return TXRX_CONTINUE;
 116 }
 117
 118 ieee80211_rx_handler ieee80211_rx_pre_handlers[] =
 119 {
 120         ieee80211_rx_h_parse_qos,
 121         ieee80211_rx_h_load_stats,
 122         NULL
 123 };
 124
 125 /* rx handlers */
 126
 127 static ieee80211_txrx_result
 128 ieee80211_rx_h_if_stats(struct ieee80211_txrx_data *rx)
 129 {
 130         if (rx->sta)
 131                 rx->sta->channel_use_raw += rx->u.rx.load;
 132         rx->sdata->channel_use_raw += rx->u.rx.load;
 133         return TXRX_CONTINUE;
 134 }
 135
 136 static void
 137 ieee80211_rx_monitor(struct net_device *dev, struct sk_buff *skb,
 138                      struct ieee80211_rx_status *status)
 139 {
 140         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 141         struct ieee80211_sub_if_data *sdata;
 142         struct ieee80211_rate *rate;
 143         struct ieee80211_rtap_hdr {
 144                 struct ieee80211_radiotap_header hdr;
 145                 u8 flags;
 146                 u8 rate;
 147                 __le16 chan_freq;
 148                 __le16 chan_flags;
 149                 u8 antsignal;
 150         } __attribute__ ((packed)) *rthdr;
 151
 152         skb->dev = dev;
 153
 154         sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 155
 156         if (status->flag & RX_FLAG_RADIOTAP)
 157                 goto out;
 158
 159         if (skb_headroom(skb) < sizeof(*rthdr)) {
 160                 I802_DEBUG_INC(local->rx_expand_skb_head);
 161                 if (pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC)) {
 162                         dev_kfree_skb(skb);
 163                         return;
 164                 }
 165         }
 166
 167         rthdr = (struct ieee80211_rtap_hdr *) skb_push(skb, sizeof(*rthdr));
 168         memset(rthdr, 0, sizeof(*rthdr));
 169         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
 170         rthdr->hdr.it_present =
 171                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 172                             (1 << IEEE80211_RADIOTAP_RATE) |
 173                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
 174                             (1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL));
 175         rthdr->flags = local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS ?
 176                        IEEE80211_RADIOTAP_F_FCS : 0;
 177         rate = ieee80211_get_rate(local, status->phymode, status->rate);
 178         if (rate)
 179                 rthdr->rate = rate->rate / 5;
 180         rthdr->chan_freq = cpu_to_le16(status->freq);
 181         rthdr->chan_flags =
 182                 status->phymode == MODE_IEEE80211A ?
 183                 cpu_to_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ) :
 184                 cpu_to_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ);
 185         rthdr->antsignal = status->ssi;
 186
 187  out:
 188         sdata->stats.rx_packets++;
 189         sdata->stats.rx_bytes += skb->len;
 190
 191         skb_set_mac_header(skb, 0);
 192         skb->ip_summed = CHECKSUM_UNNECESSARY;
 193         skb->pkt_type = PACKET_OTHERHOST;
 194         skb->protocol = htons(ETH_P_802_2);
 195         memset(skb->cb, 0, sizeof(skb->cb));
 196         netif_rx(skb);
 197 }
 198
 199 static ieee80211_txrx_result
 200 ieee80211_rx_h_monitor(struct ieee80211_txrx_data *rx)
 201 {
 202         if (rx->sdata->type == IEEE80211_IF_TYPE_MNTR) {
 203                 ieee80211_rx_monitor(rx->dev, rx->skb, rx->u.rx.status);
 204                 return TXRX_QUEUED;
 205         }
 206
 207         if (rx->u.rx.status->flag & RX_FLAG_RADIOTAP)
 208                 skb_pull(rx->skb, ieee80211_get_radiotap_len(rx->skb->data));
 209
 210         return TXRX_CONTINUE;
 211 }
 212
 213 static ieee80211_txrx_result
 214 ieee80211_rx_h_passive_scan(struct ieee80211_txrx_data *rx)
 215 {
 216         struct ieee80211_local *local = rx->local;
 217         struct sk_buff *skb = rx->skb;
 218
 219         if (unlikely(local->sta_scanning != 0)) {
 220                 ieee80211_sta_rx_scan(rx->dev, skb, rx->u.rx.status);
 221                 return TXRX_QUEUED;
 222         }
 223
 224         if (unlikely(rx->u.rx.in_scan)) {
 225                 /* scanning finished during invoking of handlers */
 226                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
 227                 return TXRX_DROP;
 228         }
 229
 230         return TXRX_CONTINUE;
 231 }
 232
 233 static ieee80211_txrx_result
 234 ieee80211_rx_h_check(struct ieee80211_txrx_data *rx)
 235 {
 236         struct ieee80211_hdr *hdr;
 237         hdr = (struct ieee80211_hdr *) rx->skb->data;
 238
 239         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 240         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 241                 if (unlikely(rx->fc & IEEE80211_FCTL_RETRY &&
 242                              rx->sta->last_seq_ctrl[rx->u.rx.queue] ==
 243                              hdr->seq_ctrl)) {
 244                         if (rx->u.rx.ra_match) {
 245                                 rx->local->dot11FrameDuplicateCount++;
 246                                 rx->sta->num_duplicates++;
 247                         }
 248                         return TXRX_DROP;
 249                 } else
 250                         rx->sta->last_seq_ctrl[rx->u.rx.queue] = hdr->seq_ctrl;
 251         }
 252
 253         if ((rx->local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) &&
 254             rx->skb->len > FCS_LEN)
 255                 skb_trim(rx->skb, rx->skb->len - FCS_LEN);
 256
 257         if (unlikely(rx->skb->len < 16)) {
 258                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 259                 return TXRX_DROP;
 260         }
 261
 262         if (!rx->u.rx.ra_match)
 263                 rx->skb->pkt_type = PACKET_OTHERHOST;
 264         else if (compare_ether_addr(rx->dev->dev_addr, hdr->addr1) == 0)
 265                 rx->skb->pkt_type = PACKET_HOST;
 266         else if (is_multicast_ether_addr(hdr->addr1)) {
 267                 if (is_broadcast_ether_addr(hdr->addr1))
 268                         rx->skb->pkt_type = PACKET_BROADCAST;
 269                 else
 270                         rx->skb->pkt_type = PACKET_MULTICAST;
 271         } else
 272                 rx->skb->pkt_type = PACKET_OTHERHOST;
 273
 274         /* Drop disallowed frame classes based on STA auth/assoc state;
 275          * IEEE 802.11, Chap 5.5.
 276          *
 277          * 80211.o does filtering only based on association state, i.e., it
 278          * drops Class 3 frames from not associated stations. hostapd sends
 279          * deauth/disassoc frames when needed. In addition, hostapd is
 280          * responsible for filtering on both auth and assoc states.
 281          */
 282         if (unlikely(((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA ||
 283                       ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_CTL &&
 284                        (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PSPOLL)) &&
 285                      rx->sdata->type != IEEE80211_IF_TYPE_IBSS &&
 286                      (!rx->sta || !(rx->sta->flags & WLAN_STA_ASSOC)))) {
 287                 if ((!(rx->fc & IEEE80211_FCTL_FROMDS) &&
 288                      !(rx->fc & IEEE80211_FCTL_TODS) &&
 289                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA)
 290                     || !rx->u.rx.ra_match) {
 291                         /* Drop IBSS frames and frames for other hosts
 292                          * silently. */
 293                         return TXRX_DROP;
 294                 }
 295
 296                 if (!rx->local->apdev)
 297                         return TXRX_DROP;
 298
 299                 ieee80211_rx_mgmt(rx->local, rx->skb, rx->u.rx.status,
 300                                   ieee80211_msg_sta_not_assoc);
 301                 return TXRX_QUEUED;
 302         }
 303
 304         return TXRX_CONTINUE;
 305 }
 306
 307
 308 static ieee80211_txrx_result
 309 ieee80211_rx_h_load_key(struct ieee80211_txrx_data *rx)
 310 {
 311         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 312         int keyidx;
 313         int hdrlen;
 314
 315         /*
 316          * Key selection 101
 317          *
 318          * There are three types of keys:
 319          *  - GTK (group keys)
 320          *  - PTK (pairwise keys)
 321          *  - STK (station-to-station pairwise keys)
 322          *
 323          * When selecting a key, we have to distinguish between multicast
 324          * (including broadcast) and unicast frames, the latter can only
 325          * use PTKs and STKs while the former always use GTKs. Unless, of
 326          * course, actual WEP keys ("pre-RSNA") are used, then unicast
 327          * frames can also use key indizes like GTKs. Hence, if we don't
 328          * have a PTK/STK we check the key index for a WEP key.
 329          *
 330          * There is also a slight problem in IBSS mode: GTKs are negotiated
 331          * with each station, that is something we don't currently handle.
 332          */
 333
 334         if (!(rx->fc & IEEE80211_FCTL_PROTECTED))
 335                 return TXRX_CONTINUE;
 336
 337         /*
 338          * No point in finding a key if the frame is neither
 339          * addressed to us nor a multicast frame.
 340          */
 341         if (!rx->u.rx.ra_match)
 342                 return TXRX_CONTINUE;
 343
 344         if (!is_multicast_ether_addr(hdr->addr1) && rx->sta && rx->sta->key) {
 345                 rx->key = rx->sta->key;
 346         } else {
 347                 /*
 348                  * The device doesn't give us the IV so we won't be
 349                  * able to look up the key. That's ok though, we
 350                  * don't need to decrypt the frame, we just won't
 351                  * be able to keep statistics accurate.
 352                  * Except for key threshold notifications, should
 353                  * we somehow allow the driver to tell us which key
 354                  * the hardware used if this flag is set?
 355                  */
 356                 if (!(rx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV))
 357                         return TXRX_CONTINUE;
 358
 359                 hdrlen = ieee80211_get_hdrlen(rx->fc);
 360
 361                 if (rx->skb->len < 8 + hdrlen)
 362                         return TXRX_DROP; /* TODO: count this? */
 363
 364                 /*
 365                  * no need to call ieee80211_wep_get_keyidx,
 366                  * it verifies a bunch of things we've done already
 367                  */
 368                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
 369
 370                 rx->key = rx->sdata->keys[keyidx];
 371
 372                 /*
 373                  * RSNA-protected unicast frames should always be sent with
 374                  * pairwise or station-to-station keys, but for WEP we allow
 375                  * using a key index as well.
 376                  */
 377                 if (rx->key && rx->key->alg != ALG_WEP &&
 378                     !is_multicast_ether_addr(hdr->addr1))
 379                         rx->key = NULL;
 380         }
 381
 382         if (rx->key) {
 383                 rx->key->tx_rx_count++;
 384                 if (unlikely(rx->local->key_tx_rx_threshold &&
 385                              rx->key->tx_rx_count >
 386                              rx->local->key_tx_rx_threshold)) {
 387                         ieee80211_key_threshold_notify(rx->dev, rx->key,
 388                                                        rx->sta);
 389                 }
 390         }
 391
 392         return TXRX_CONTINUE;
 393 }
 394
 395 static void ap_sta_ps_start(struct net_device *dev, struct sta_info *sta)
 396 {
 397         struct ieee80211_sub_if_data *sdata;
 398         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 399
 400         if (sdata->bss)
 401                 atomic_inc(&sdata->bss->num_sta_ps);
 402         sta->flags |= WLAN_STA_PS;
 403         sta->pspoll = 0;
 404 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 405         printk(KERN_DEBUG "%s: STA " MAC_FMT " aid %d enters power "
 406                "save mode\n", dev->name, MAC_ARG(sta->addr), sta->aid);
 407 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 408 }
 409
 410 static int ap_sta_ps_end(struct net_device *dev, struct sta_info *sta)
 411 {
 412         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 413         struct sk_buff *skb;
 414         int sent = 0;
 415         struct ieee80211_sub_if_data *sdata;
 416         struct ieee80211_tx_packet_data *pkt_data;
 417
 418         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 419         if (sdata->bss)
 420                 atomic_dec(&sdata->bss->num_sta_ps);
 421         sta->flags &= ~(WLAN_STA_PS | WLAN_STA_TIM);
 422         sta->pspoll = 0;
 423         if (!skb_queue_empty(&sta->ps_tx_buf)) {
 424                 if (local->ops->set_tim)
 425                         local->ops->set_tim(local_to_hw(local), sta->aid, 0);
 426                 if (sdata->bss)
 427                         bss_tim_clear(local, sdata->bss, sta->aid);
 428         }
 429 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 430         printk(KERN_DEBUG "%s: STA " MAC_FMT " aid %d exits power "
 431                "save mode\n", dev->name, MAC_ARG(sta->addr), sta->aid);
 432 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 433         /* Send all buffered frames to the station */
 434         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
 435                 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 436                 sent++;
 437                 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
 438                 dev_queue_xmit(skb);
 439         }
 440         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
 441                 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 442                 local->total_ps_buffered--;
 443                 sent++;
 444 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 445                 printk(KERN_DEBUG "%s: STA " MAC_FMT " aid %d send PS frame "
 446                        "since STA not sleeping anymore\n", dev->name,
 447                        MAC_ARG(sta->addr), sta->aid);
 448 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 449                 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
 450                 dev_queue_xmit(skb);
 451         }
 452
 453         return sent;
 454 }
 455
 456 static ieee80211_txrx_result
 457 ieee80211_rx_h_sta_process(struct ieee80211_txrx_data *rx)
 458 {
 459         struct sta_info *sta = rx->sta;
 460         struct net_device *dev = rx->dev;
 461         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 462
 463         if (!sta)
 464                 return TXRX_CONTINUE;
 465
 466         /* Update last_rx only for IBSS packets which are for the current
 467          * BSSID to avoid keeping the current IBSS network alive in cases where
 468          * other STAs are using different BSSID. */
 469         if (rx->sdata->type == IEEE80211_IF_TYPE_IBSS) {
 470                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len);
 471                 if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0)
 472                         sta->last_rx = jiffies;
 473         } else
 474         if (!is_multicast_ether_addr(hdr->addr1) ||
 475             rx->sdata->type == IEEE80211_IF_TYPE_STA) {
 476                 /* Update last_rx only for unicast frames in order to prevent
 477                  * the Probe Request frames (the only broadcast frames from a
 478                  * STA in infrastructure mode) from keeping a connection alive.
 479                  */
 480                 sta->last_rx = jiffies;
 481         }
 482
 483         if (!rx->u.rx.ra_match)
 484                 return TXRX_CONTINUE;
 485
 486         sta->rx_fragments++;
 487         sta->rx_bytes += rx->skb->len;
 488         sta->last_rssi = (sta->last_rssi * 15 +
 489                           rx->u.rx.status->ssi) / 16;
 490         sta->last_signal = (sta->last_signal * 15 +
 491                             rx->u.rx.status->signal) / 16;
 492         sta->last_noise = (sta->last_noise * 15 +
 493                            rx->u.rx.status->noise) / 16;
 494
 495         if (!(rx->fc & IEEE80211_FCTL_MOREFRAGS)) {
 496                 /* Change STA power saving mode only in the end of a frame
 497                  * exchange sequence */
 498                 if ((sta->flags & WLAN_STA_PS) && !(rx->fc & IEEE80211_FCTL_PM))
 499                         rx->u.rx.sent_ps_buffered += ap_sta_ps_end(dev, sta);
 500                 else if (!(sta->flags & WLAN_STA_PS) &&
 501                          (rx->fc & IEEE80211_FCTL_PM))
 502                         ap_sta_ps_start(dev, sta);
 503         }
 504
 505         /* Drop data::nullfunc frames silently, since they are used only to
 506          * control station power saving mode. */
 507         if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 508             (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_NULLFUNC) {
 509                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
 510                 /* Update counter and free packet here to avoid counting this
 511                  * as a dropped packed. */
 512                 sta->rx_packets++;
 513                 dev_kfree_skb(rx->skb);
 514                 return TXRX_QUEUED;
 515         }
 516
 517         return TXRX_CONTINUE;
 518 } /* ieee80211_rx_h_sta_process */
 519
 520 static ieee80211_txrx_result
 521 ieee80211_rx_h_wep_weak_iv_detection(struct ieee80211_txrx_data *rx)
 522 {
 523         if (!rx->sta || !(rx->fc & IEEE80211_FCTL_PROTECTED) ||
 524             (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA ||
 525             !rx->key || rx->key->alg != ALG_WEP || !rx->u.rx.ra_match)
 526                 return TXRX_CONTINUE;
 527
 528         /* Check for weak IVs, if hwaccel did not remove IV from the frame */
 529         if ((rx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV) ||
 530             rx->key->force_sw_encrypt) {
 531                 u8 *iv = ieee80211_wep_is_weak_iv(rx->skb, rx->key);
 532                 if (iv) {
 533                         rx->sta->wep_weak_iv_count++;
 534                 }
 535         }
 536
 537         return TXRX_CONTINUE;
 538 }
 539
 540 static ieee80211_txrx_result
 541 ieee80211_rx_h_wep_decrypt(struct ieee80211_txrx_data *rx)
 542 {
 543         if ((rx->key && rx->key->alg != ALG_WEP) ||
 544             !(rx->fc & IEEE80211_FCTL_PROTECTED) ||
 545             ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
 546              ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
 547               (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)))
 548                 return TXRX_CONTINUE;
 549
 550         if (!rx->key) {
 551                 if (net_ratelimit())
 552                         printk(KERN_DEBUG "%s: RX WEP frame, but no key set\n",
 553                                rx->dev->name);
 554                 return TXRX_DROP;
 555         }
 556
 557         if (!(rx->u.rx.status->flag & RX_FLAG_DECRYPTED) ||
 558             rx->key->force_sw_encrypt) {
 559                 if (ieee80211_wep_decrypt(rx->local, rx->skb, rx->key)) {
 560                         if (net_ratelimit())
 561                                 printk(KERN_DEBUG "%s: RX WEP frame, decrypt "
 562                                        "failed\n", rx->dev->name);
 563                         return TXRX_DROP;
 564                 }
 565         } else if (rx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV) {
 566                 ieee80211_wep_remove_iv(rx->local, rx->skb, rx->key);
 567                 /* remove ICV */
 568                 skb_trim(rx->skb, rx->skb->len - 4);
 569         }
 570
 571         return TXRX_CONTINUE;
 572 }
 573
 574 static inline struct ieee80211_fragment_entry *
 575 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
 576                          unsigned int frag, unsigned int seq, int rx_queue,
 577                          struct sk_buff **skb)
 578 {
 579         struct ieee80211_fragment_entry *entry;
 580         int idx;
 581
 582         idx = sdata->fragment_next;
 583         entry = &sdata->fragments[sdata->fragment_next++];
 584         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
 585                 sdata->fragment_next = 0;
 586
 587         if (!skb_queue_empty(&entry->skb_list)) {
 588 #ifdef CONFIG_MAC80211_DEBUG
 589                 struct ieee80211_hdr *hdr =
 590                         (struct ieee80211_hdr *) entry->skb_list.next->data;
 591                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
 592                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
 593                        "addr1=" MAC_FMT " addr2=" MAC_FMT "\n",
 594                        sdata->dev->name, idx,
 595                        jiffies - entry->first_frag_time, entry->seq,
 596                        entry->last_frag, MAC_ARG(hdr->addr1),
 597                        MAC_ARG(hdr->addr2));
 598 #endif /* CONFIG_MAC80211_DEBUG */
 599                 __skb_queue_purge(&entry->skb_list);
 600         }
 601
 602         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
 603         *skb = NULL;
 604         entry->first_frag_time = jiffies;
 605         entry->seq = seq;
 606         entry->rx_queue = rx_queue;
 607         entry->last_frag = frag;
 608         entry->ccmp = 0;
 609         entry->extra_len = 0;
 610
 611         return entry;
 612 }
 613
 614 static inline struct ieee80211_fragment_entry *
 615 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
 616                           u16 fc, unsigned int frag, unsigned int seq,
 617                           int rx_queue, struct ieee80211_hdr *hdr)
 618 {
 619         struct ieee80211_fragment_entry *entry;
 620         int i, idx;
 621
 622         idx = sdata->fragment_next;
 623         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
 624                 struct ieee80211_hdr *f_hdr;
 625                 u16 f_fc;
 626
 627                 idx--;
 628                 if (idx < 0)
 629                         idx = IEEE80211_FRAGMENT_MAX - 1;
 630
 631                 entry = &sdata->fragments[idx];
 632                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
 633                     entry->rx_queue != rx_queue ||
 634                     entry->last_frag + 1 != frag)
 635                         continue;
 636
 637                 f_hdr = (struct ieee80211_hdr *) entry->skb_list.next->data;
 638                 f_fc = le16_to_cpu(f_hdr->frame_control);
 639
 640                 if ((fc & IEEE80211_FCTL_FTYPE) != (f_fc & IEEE80211_FCTL_FTYPE) ||
 641                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
 642                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
 643                         continue;
 644
 645                 if (entry->first_frag_time + 2 * HZ < jiffies) {
 646                         __skb_queue_purge(&entry->skb_list);
 647                         continue;
 648                 }
 649                 return entry;
 650         }
 651
 652         return NULL;
 653 }
 654
 655 static ieee80211_txrx_result
 656 ieee80211_rx_h_defragment(struct ieee80211_txrx_data *rx)
 657 {
 658         struct ieee80211_hdr *hdr;
 659         u16 sc;
 660         unsigned int frag, seq;
 661         struct ieee80211_fragment_entry *entry;
 662         struct sk_buff *skb;
 663
 664         hdr = (struct ieee80211_hdr *) rx->skb->data;
 665         sc = le16_to_cpu(hdr->seq_ctrl);
 666         frag = sc & IEEE80211_SCTL_FRAG;
 667
 668         if (likely((!(rx->fc & IEEE80211_FCTL_MOREFRAGS) && frag == 0) ||
 669                    (rx->skb)->len < 24 ||
 670                    is_multicast_ether_addr(hdr->addr1))) {
 671                 /* not fragmented */
 672                 goto out;
 673         }
 674         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
 675
 676         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
 677
 678         if (frag == 0) {
 679                 /* This is the first fragment of a new frame. */
 680                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
 681                                                  rx->u.rx.queue, &(rx->skb));
 682                 if (rx->key && rx->key->alg == ALG_CCMP &&
 683                     (rx->fc & IEEE80211_FCTL_PROTECTED)) {
 684                         /* Store CCMP PN so that we can verify that the next
 685                          * fragment has a sequential PN value. */
 686                         entry->ccmp = 1;
 687                         memcpy(entry->last_pn,
 688                                rx->key->u.ccmp.rx_pn[rx->u.rx.queue],
 689                                CCMP_PN_LEN);
 690                 }
 691                 return TXRX_QUEUED;
 692         }
 693
 694         /* This is a fragment for a frame that should already be pending in
 695          * fragment cache. Add this fragment to the end of the pending entry.
 696          */
 697         entry = ieee80211_reassemble_find(rx->sdata, rx->fc, frag, seq,
 698                                           rx->u.rx.queue, hdr);
 699         if (!entry) {
 700                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 701                 return TXRX_DROP;
 702         }
 703
 704         /* Verify that MPDUs within one MSDU have sequential PN values.
 705          * (IEEE 802.11i, 8.3.3.4.5) */
 706         if (entry->ccmp) {
 707                 int i;
 708                 u8 pn[CCMP_PN_LEN], *rpn;
 709                 if (!rx->key || rx->key->alg != ALG_CCMP)
 710                         return TXRX_DROP;
 711                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
 712                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
 713                         pn[i]++;
 714                         if (pn[i])
 715                                 break;
 716                 }
 717                 rpn = rx->key->u.ccmp.rx_pn[rx->u.rx.queue];
 718                 if (memcmp(pn, rpn, CCMP_PN_LEN) != 0) {
 719                         if (net_ratelimit())
 720                                 printk(KERN_DEBUG "%s: defrag: CCMP PN not "
 721                                        "sequential A2=" MAC_FMT
 722                                        " PN=%02x%02x%02x%02x%02x%02x "
 723                                        "(expected %02x%02x%02x%02x%02x%02x)\n",
 724                                        rx->dev->name, MAC_ARG(hdr->addr2),
 725                                        rpn[0], rpn[1], rpn[2], rpn[3], rpn[4],
 726                                        rpn[5], pn[0], pn[1], pn[2], pn[3],
 727                                        pn[4], pn[5]);
 728                         return TXRX_DROP;
 729                 }
 730                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
 731         }
 732
 733         skb_pull(rx->skb, ieee80211_get_hdrlen(rx->fc));
 734         __skb_queue_tail(&entry->skb_list, rx->skb);
 735         entry->last_frag = frag;
 736         entry->extra_len += rx->skb->len;
 737         if (rx->fc & IEEE80211_FCTL_MOREFRAGS) {
 738                 rx->skb = NULL;
 739                 return TXRX_QUEUED;
 740         }
 741
 742         rx->skb = __skb_dequeue(&entry->skb_list);
 743         if (skb_tailroom(rx->skb) < entry->extra_len) {
 744                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
 745                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
 746                                               GFP_ATOMIC))) {
 747                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 748                         __skb_queue_purge(&entry->skb_list);
 749                         return TXRX_DROP;
 750                 }
 751         }
 752         while ((skb = __skb_dequeue(&entry->skb_list))) {
 753                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
 754                 dev_kfree_skb(skb);
 755         }
 756
 757         /* Complete frame has been reassembled - process it now */
 758         rx->fragmented = 1;
 759
 760  out:
 761         if (rx->sta)
 762                 rx->sta->rx_packets++;
 763         if (is_multicast_ether_addr(hdr->addr1))
 764                 rx->local->dot11MulticastReceivedFrameCount++;
 765         else
 766                 ieee80211_led_rx(rx->local);
 767         return TXRX_CONTINUE;
 768 }
 769
 770 static ieee80211_txrx_result
 771 ieee80211_rx_h_ps_poll(struct ieee80211_txrx_data *rx)
 772 {
 773         struct sk_buff *skb;
 774         int no_pending_pkts;
 775
 776         if (likely(!rx->sta ||
 777                    (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL ||
 778                    (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PSPOLL ||
 779                    !rx->u.rx.ra_match))
 780                 return TXRX_CONTINUE;
 781
 782         skb = skb_dequeue(&rx->sta->tx_filtered);
 783         if (!skb) {
 784                 skb = skb_dequeue(&rx->sta->ps_tx_buf);
 785                 if (skb)
 786                         rx->local->total_ps_buffered--;
 787         }
 788         no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
 789                 skb_queue_empty(&rx->sta->ps_tx_buf);
 790
 791         if (skb) {
 792                 struct ieee80211_hdr *hdr =
 793                         (struct ieee80211_hdr *) skb->data;
 794
 795                 /* tell TX path to send one frame even though the STA may
 796                  * still remain is PS mode after this frame exchange */
 797                 rx->sta->pspoll = 1;
 798
 799 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 800                 printk(KERN_DEBUG "STA " MAC_FMT " aid %d: PS Poll (entries "
 801                        "after %d)\n",
 802                        MAC_ARG(rx->sta->addr), rx->sta->aid,
 803                        skb_queue_len(&rx->sta->ps_tx_buf));
 804 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 805
 806                 /* Use MoreData flag to indicate whether there are more
 807                  * buffered frames for this STA */
 808                 if (no_pending_pkts) {
 809                         hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
 810                         rx->sta->flags &= ~WLAN_STA_TIM;
 811                 } else
 812                         hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
 813
 814                 dev_queue_xmit(skb);
 815
 816                 if (no_pending_pkts) {
 817                         if (rx->local->ops->set_tim)
 818                                 rx->local->ops->set_tim(local_to_hw(rx->local),
 819                                                        rx->sta->aid, 0);
 820                         if (rx->sdata->bss)
 821                                 bss_tim_clear(rx->local, rx->sdata->bss, rx->sta->aid);
 822                 }
 823 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 824         } else if (!rx->u.rx.sent_ps_buffered) {
 825                 printk(KERN_DEBUG "%s: STA " MAC_FMT " sent PS Poll even "
 826                        "though there is no buffered frames for it\n",
 827                        rx->dev->name, MAC_ARG(rx->sta->addr));
 828 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 829
 830         }
 831
 832         /* Free PS Poll skb here instead of returning TXRX_DROP that would
 833          * count as an dropped frame. */
 834         dev_kfree_skb(rx->skb);
 835
 836         return TXRX_QUEUED;
 837 }
 838
 839 static ieee80211_txrx_result
 840 ieee80211_rx_h_remove_qos_control(struct ieee80211_txrx_data *rx)
 841 {
 842         u16 fc = rx->fc;
 843         u8 *data = rx->skb->data;
 844         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) data;
 845
 846         if (!WLAN_FC_IS_QOS_DATA(fc))
 847                 return TXRX_CONTINUE;
 848
 849         /* remove the qos control field, update frame type and meta-data */
 850         memmove(data + 2, data, ieee80211_get_hdrlen(fc) - 2);
 851         hdr = (struct ieee80211_hdr *) skb_pull(rx->skb, 2);
 852         /* change frame type to non QOS */
 853         rx->fc = fc &= ~IEEE80211_STYPE_QOS_DATA;
 854         hdr->frame_control = cpu_to_le16(fc);
 855
 856         return TXRX_CONTINUE;
 857 }
 858
 859 static ieee80211_txrx_result
 860 ieee80211_rx_h_802_1x_pae(struct ieee80211_txrx_data *rx)
 861 {
 862         if (rx->sdata->eapol && ieee80211_is_eapol(rx->skb) &&
 863             rx->sdata->type != IEEE80211_IF_TYPE_STA && rx->u.rx.ra_match) {
 864                 /* Pass both encrypted and unencrypted EAPOL frames to user
 865                  * space for processing. */
 866                 if (!rx->local->apdev)
 867                         return TXRX_DROP;
 868                 ieee80211_rx_mgmt(rx->local, rx->skb, rx->u.rx.status,
 869                                   ieee80211_msg_normal);
 870                 return TXRX_QUEUED;
 871         }
 872
 873         if (unlikely(rx->sdata->ieee802_1x &&
 874                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 875                      (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
 876                      (!rx->sta || !(rx->sta->flags & WLAN_STA_AUTHORIZED)) &&
 877                      !ieee80211_is_eapol(rx->skb))) {
 878 #ifdef CONFIG_MAC80211_DEBUG
 879                 struct ieee80211_hdr *hdr =
 880                         (struct ieee80211_hdr *) rx->skb->data;
 881                 printk(KERN_DEBUG "%s: dropped frame from " MAC_FMT
 882                        " (unauthorized port)\n", rx->dev->name,
 883                        MAC_ARG(hdr->addr2));
 884 #endif /* CONFIG_MAC80211_DEBUG */
 885                 return TXRX_DROP;
 886         }
 887
 888         return TXRX_CONTINUE;
 889 }
 890
 891 static ieee80211_txrx_result
 892 ieee80211_rx_h_drop_unencrypted(struct ieee80211_txrx_data *rx)
 893 {
 894         /*
 895          * Pass through unencrypted frames if the hardware might have
 896          * decrypted them already without telling us, but that can only
 897          * be true if we either didn't find a key or the found key is
 898          * uploaded to the hardware.
 899          */
 900         if ((rx->local->hw.flags & IEEE80211_HW_DEVICE_HIDES_WEP) &&
 901             (!rx->key || !rx->key->force_sw_encrypt))
 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                         return TXRX_DROP;
 997                 }
 998                 break;
 999         case 0:
1000                 /* DA SA BSSID */
1001                 memcpy(dst, hdr->addr1, ETH_ALEN);
1002                 memcpy(src, hdr->addr2, ETH_ALEN);
1003
1004                 if (sdata->type != IEEE80211_IF_TYPE_IBSS) {
1005                         if (net_ratelimit()) {
1006                                 printk(KERN_DEBUG "%s: dropped IBSS frame (DA="
1007                                        MAC_FMT " SA=" MAC_FMT " BSSID=" MAC_FMT
1008                                        ")\n",
1009                                        dev->name, MAC_ARG(hdr->addr1),
1010                                        MAC_ARG(hdr->addr2),
1011                                        MAC_ARG(hdr->addr3));
1012                         }
1013                         return TXRX_DROP;
1014                 }
1015                 break;
1016         }
1017
1018         payload = skb->data + hdrlen;
1019
1020         if (unlikely(skb->len - hdrlen < 8)) {
1021                 if (net_ratelimit()) {
1022                         printk(KERN_DEBUG "%s: RX too short data frame "
1023                                "payload\n", dev->name);
1024                 }
1025                 return TXRX_DROP;
1026         }
1027
1028         ethertype = (payload[6] << 8) | payload[7];
1029
1030         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1031                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1032                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1033                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1034                  * replace EtherType */
1035                 skb_pull(skb, hdrlen + 6);
1036                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1037                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1038         } else {
1039                 struct ethhdr *ehdr;
1040                 __be16 len;
1041                 skb_pull(skb, hdrlen);
1042                 len = htons(skb->len);
1043                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1044                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1045                 memcpy(ehdr->h_source, src, ETH_ALEN);
1046                 ehdr->h_proto = len;
1047         }
1048         skb->dev = dev;
1049
1050         skb2 = NULL;
1051
1052         sdata->stats.rx_packets++;
1053         sdata->stats.rx_bytes += skb->len;
1054
1055         if (local->bridge_packets && (sdata->type == IEEE80211_IF_TYPE_AP
1056             || sdata->type == IEEE80211_IF_TYPE_VLAN) && rx->u.rx.ra_match) {
1057                 if (is_multicast_ether_addr(skb->data)) {
1058                         /* send multicast frames both to higher layers in
1059                          * local net stack and back to the wireless media */
1060                         skb2 = skb_copy(skb, GFP_ATOMIC);
1061                         if (!skb2 && net_ratelimit())
1062                                 printk(KERN_DEBUG "%s: failed to clone "
1063                                        "multicast frame\n", dev->name);
1064                 } else {
1065                         struct sta_info *dsta;
1066                         dsta = sta_info_get(local, skb->data);
1067                         if (dsta && !dsta->dev) {
1068                                 if (net_ratelimit())
1069                                         printk(KERN_DEBUG "Station with null "
1070                                                "dev structure!\n");
1071                         } else if (dsta && dsta->dev == dev) {
1072                                 /* Destination station is associated to this
1073                                  * AP, so send the frame directly to it and
1074                                  * do not pass the frame to local net stack.
1075                                  */
1076                                 skb2 = skb;
1077                                 skb = NULL;
1078                         }
1079                         if (dsta)
1080                                 sta_info_put(dsta);
1081                 }
1082         }
1083
1084         if (skb) {
1085                 /* deliver to local stack */
1086                 skb->protocol = eth_type_trans(skb, dev);
1087                 memset(skb->cb, 0, sizeof(skb->cb));
1088                 netif_rx(skb);
1089         }
1090
1091         if (skb2) {
1092                 /* send to wireless media */
1093                 skb2->protocol = __constant_htons(ETH_P_802_3);
1094                 skb_set_network_header(skb2, 0);
1095                 skb_set_mac_header(skb2, 0);
1096                 dev_queue_xmit(skb2);
1097         }
1098
1099         return TXRX_QUEUED;
1100 }
1101
1102 static ieee80211_txrx_result
1103 ieee80211_rx_h_mgmt(struct ieee80211_txrx_data *rx)
1104 {
1105         struct ieee80211_sub_if_data *sdata;
1106
1107         if (!rx->u.rx.ra_match)
1108                 return TXRX_DROP;
1109
1110         sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1111         if ((sdata->type == IEEE80211_IF_TYPE_STA ||
1112              sdata->type == IEEE80211_IF_TYPE_IBSS) &&
1113             !rx->local->user_space_mlme) {
1114                 ieee80211_sta_rx_mgmt(rx->dev, rx->skb, rx->u.rx.status);
1115         } else {
1116                 /* Management frames are sent to hostapd for processing */
1117                 if (!rx->local->apdev)
1118                         return TXRX_DROP;
1119                 ieee80211_rx_mgmt(rx->local, rx->skb, rx->u.rx.status,
1120                                   ieee80211_msg_normal);
1121         }
1122         return TXRX_QUEUED;
1123 }
1124
1125 static inline ieee80211_txrx_result __ieee80211_invoke_rx_handlers(
1126                                 struct ieee80211_local *local,
1127                                 ieee80211_rx_handler *handlers,
1128                                 struct ieee80211_txrx_data *rx,
1129                                 struct sta_info *sta)
1130 {
1131         ieee80211_rx_handler *handler;
1132         ieee80211_txrx_result res = TXRX_DROP;
1133
1134         for (handler = handlers; *handler != NULL; handler++) {
1135                 res = (*handler)(rx);
1136
1137                 switch (res) {
1138                 case TXRX_CONTINUE:
1139                         continue;
1140                 case TXRX_DROP:
1141                         I802_DEBUG_INC(local->rx_handlers_drop);
1142                         if (sta)
1143                                 sta->rx_dropped++;
1144                         break;
1145                 case TXRX_QUEUED:
1146                         I802_DEBUG_INC(local->rx_handlers_queued);
1147                         break;
1148                 }
1149                 break;
1150         }
1151
1152         if (res == TXRX_DROP)
1153                 dev_kfree_skb(rx->skb);
1154         return res;
1155 }
1156
1157 static inline void ieee80211_invoke_rx_handlers(struct ieee80211_local *local,
1158                                                 ieee80211_rx_handler *handlers,
1159                                                 struct ieee80211_txrx_data *rx,
1160                                                 struct sta_info *sta)
1161 {
1162         if (__ieee80211_invoke_rx_handlers(local, handlers, rx, sta) ==
1163             TXRX_CONTINUE)
1164                 dev_kfree_skb(rx->skb);
1165 }
1166
1167 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1168                                             struct ieee80211_hdr *hdr,
1169                                             struct sta_info *sta,
1170                                             struct ieee80211_txrx_data *rx)
1171 {
1172         int keyidx, hdrlen;
1173
1174         hdrlen = ieee80211_get_hdrlen_from_skb(rx->skb);
1175         if (rx->skb->len >= hdrlen + 4)
1176                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1177         else
1178                 keyidx = -1;
1179
1180         /* TODO: verify that this is not triggered by fragmented
1181          * frames (hw does not verify MIC for them). */
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                 /* Some hardware versions seem to generate incorrect
1190                  * Michael MIC reports; ignore them to avoid triggering
1191                  * countermeasures. */
1192                 if (net_ratelimit())
1193                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1194                                "error for unknown address " MAC_FMT "\n",
1195                                dev->name, MAC_ARG(hdr->addr2));
1196                 goto ignore;
1197         }
1198
1199         if (!(rx->fc & IEEE80211_FCTL_PROTECTED)) {
1200                 if (net_ratelimit())
1201                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1202                                "error for a frame with no ISWEP flag (src "
1203                                MAC_FMT ")\n", dev->name, MAC_ARG(hdr->addr2));
1204                 goto ignore;
1205         }
1206
1207         if ((rx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV) &&
1208             rx->sdata->type == IEEE80211_IF_TYPE_AP && keyidx) {
1209                 /* AP with Pairwise keys support should never receive Michael
1210                  * MIC errors for non-zero keyidx because these are reserved
1211                  * for group keys and only the AP is sending real multicast
1212                  * frames in BSS. */
1213                 if (net_ratelimit())
1214                         printk(KERN_DEBUG "%s: ignored Michael MIC error for "
1215                                "a frame with non-zero keyidx (%d)"
1216                                " (src " MAC_FMT ")\n", dev->name, keyidx,
1217                                MAC_ARG(hdr->addr2));
1218                 goto ignore;
1219         }
1220
1221         if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
1222             ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
1223              (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)) {
1224                 if (net_ratelimit())
1225                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1226                                "error for a frame that cannot be encrypted "
1227                                "(fc=0x%04x) (src " MAC_FMT ")\n",
1228                                dev->name, rx->fc, MAC_ARG(hdr->addr2));
1229                 goto ignore;
1230         }
1231
1232         /* TODO: consider verifying the MIC error report with software
1233          * implementation if we get too many spurious reports from the
1234          * hardware. */
1235
1236         mac80211_ev_michael_mic_failure(rx->dev, keyidx, hdr);
1237  ignore:
1238         dev_kfree_skb(rx->skb);
1239         rx->skb = NULL;
1240 }
1241
1242 ieee80211_rx_handler ieee80211_rx_handlers[] =
1243 {
1244         ieee80211_rx_h_if_stats,
1245         ieee80211_rx_h_monitor,
1246         ieee80211_rx_h_passive_scan,
1247         ieee80211_rx_h_check,
1248         ieee80211_rx_h_load_key,
1249         ieee80211_rx_h_sta_process,
1250         ieee80211_rx_h_ccmp_decrypt,
1251         ieee80211_rx_h_tkip_decrypt,
1252         ieee80211_rx_h_wep_weak_iv_detection,
1253         ieee80211_rx_h_wep_decrypt,
1254         ieee80211_rx_h_defragment,
1255         ieee80211_rx_h_ps_poll,
1256         ieee80211_rx_h_michael_mic_verify,
1257         /* this must be after decryption - so header is counted in MPDU mic
1258          * must be before pae and data, so QOS_DATA format frames
1259          * are not passed to user space by these functions
1260          */
1261         ieee80211_rx_h_remove_qos_control,
1262         ieee80211_rx_h_802_1x_pae,
1263         ieee80211_rx_h_drop_unencrypted,
1264         ieee80211_rx_h_data,
1265         ieee80211_rx_h_mgmt,
1266         NULL
1267 };
1268
1269 /* main receive path */
1270
1271 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
1272                                 u8 *bssid, struct ieee80211_txrx_data *rx,
1273                                 struct ieee80211_hdr *hdr)
1274 {
1275         int multicast = is_multicast_ether_addr(hdr->addr1);
1276
1277         switch (sdata->type) {
1278         case IEEE80211_IF_TYPE_STA:
1279                 if (!bssid)
1280                         return 0;
1281                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1282                         if (!rx->u.rx.in_scan)
1283                                 return 0;
1284                         rx->u.rx.ra_match = 0;
1285                 } else if (!multicast &&
1286                            compare_ether_addr(sdata->dev->dev_addr,
1287                                               hdr->addr1) != 0) {
1288                         if (!sdata->promisc)
1289                                 return 0;
1290                         rx->u.rx.ra_match = 0;
1291                 }
1292                 break;
1293         case IEEE80211_IF_TYPE_IBSS:
1294                 if (!bssid)
1295                         return 0;
1296                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1297                         if (!rx->u.rx.in_scan)
1298                                 return 0;
1299                         rx->u.rx.ra_match = 0;
1300                 } else if (!multicast &&
1301                            compare_ether_addr(sdata->dev->dev_addr,
1302                                               hdr->addr1) != 0) {
1303                         if (!sdata->promisc)
1304                                 return 0;
1305                         rx->u.rx.ra_match = 0;
1306                 } else if (!rx->sta)
1307                         rx->sta = ieee80211_ibss_add_sta(sdata->dev, rx->skb,
1308                                                          bssid, hdr->addr2);
1309                 break;
1310         case IEEE80211_IF_TYPE_AP:
1311                 if (!bssid) {
1312                         if (compare_ether_addr(sdata->dev->dev_addr,
1313                                                hdr->addr1))
1314                                 return 0;
1315                 } else if (!ieee80211_bssid_match(bssid,
1316                                         sdata->dev->dev_addr)) {
1317                         if (!rx->u.rx.in_scan)
1318                                 return 0;
1319                         rx->u.rx.ra_match = 0;
1320                 }
1321                 if (sdata->dev == sdata->local->mdev && !rx->u.rx.in_scan)
1322                         /* do not receive anything via
1323                          * master device when not scanning */
1324                         return 0;
1325                 break;
1326         case IEEE80211_IF_TYPE_WDS:
1327                 if (bssid ||
1328                     (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
1329                         return 0;
1330                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
1331                         return 0;
1332                 break;
1333         }
1334
1335         return 1;
1336 }
1337
1338 /*
1339  * This is the receive path handler. It is called by a low level driver when an
1340  * 802.11 MPDU is received from the hardware.
1341  */
1342 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
1343                     struct ieee80211_rx_status *status)
1344 {
1345         struct ieee80211_local *local = hw_to_local(hw);
1346         struct ieee80211_sub_if_data *sdata;
1347         struct sta_info *sta;
1348         struct ieee80211_hdr *hdr;
1349         struct ieee80211_txrx_data rx;
1350         u16 type;
1351         int radiotap_len = 0, prepres;
1352         struct ieee80211_sub_if_data *prev = NULL;
1353         struct sk_buff *skb_new;
1354         u8 *bssid;
1355
1356         if (status->flag & RX_FLAG_RADIOTAP) {
1357                 radiotap_len = ieee80211_get_radiotap_len(skb->data);
1358                 skb_pull(skb, radiotap_len);
1359         }
1360
1361         hdr = (struct ieee80211_hdr *) skb->data;
1362         memset(&rx, 0, sizeof(rx));
1363         rx.skb = skb;
1364         rx.local = local;
1365
1366         rx.u.rx.status = status;
1367         rx.fc = skb->len >= 2 ? le16_to_cpu(hdr->frame_control) : 0;
1368         type = rx.fc & IEEE80211_FCTL_FTYPE;
1369         if (type == IEEE80211_FTYPE_DATA || type == IEEE80211_FTYPE_MGMT)
1370                 local->dot11ReceivedFragmentCount++;
1371
1372         if (skb->len >= 16) {
1373                 sta = rx.sta = sta_info_get(local, hdr->addr2);
1374                 if (sta) {
1375                         rx.dev = rx.sta->dev;
1376                         rx.sdata = IEEE80211_DEV_TO_SUB_IF(rx.dev);
1377                 }
1378         } else
1379                 sta = rx.sta = NULL;
1380
1381         if ((status->flag & RX_FLAG_MMIC_ERROR)) {
1382                 ieee80211_rx_michael_mic_report(local->mdev, hdr, sta, &rx);
1383                 goto end;
1384         }
1385
1386         if (unlikely(local->sta_scanning))
1387                 rx.u.rx.in_scan = 1;
1388
1389         if (__ieee80211_invoke_rx_handlers(local, local->rx_pre_handlers, &rx,
1390                                            sta) != TXRX_CONTINUE)
1391                 goto end;
1392         skb = rx.skb;
1393
1394         skb_push(skb, radiotap_len);
1395         if (sta && !sta->assoc_ap && !(sta->flags & WLAN_STA_WDS) &&
1396             !local->iff_promiscs && !is_multicast_ether_addr(hdr->addr1)) {
1397                 rx.u.rx.ra_match = 1;
1398                 ieee80211_invoke_rx_handlers(local, local->rx_handlers, &rx,
1399                                              rx.sta);
1400                 sta_info_put(sta);
1401                 return;
1402         }
1403
1404         bssid = ieee80211_get_bssid(hdr, skb->len - radiotap_len);
1405
1406         read_lock(&local->sub_if_lock);
1407         list_for_each_entry(sdata, &local->sub_if_list, list) {
1408                 rx.u.rx.ra_match = 1;
1409
1410                 if (!netif_running(sdata->dev))
1411                         continue;
1412
1413                 prepres = prepare_for_handlers(sdata, bssid, &rx, hdr);
1414                 /* prepare_for_handlers can change sta */
1415                 sta = rx.sta;
1416
1417                 if (!prepres)
1418                         continue;
1419
1420                 /*
1421                  * frame is destined for this interface, but if it's not
1422                  * also for the previous one we handle that after the
1423                  * loop to avoid copying the SKB once too much
1424                  */
1425
1426                 if (!prev) {
1427                         prev = sdata;
1428                         continue;
1429                 }
1430
1431                 /*
1432                  * frame was destined for the previous interface
1433                  * so invoke RX handlers for it
1434                  */
1435
1436                 skb_new = skb_copy(skb, GFP_ATOMIC);
1437                 if (!skb_new) {
1438                         if (net_ratelimit())
1439                                 printk(KERN_DEBUG "%s: failed to copy "
1440                                        "multicast frame for %s",
1441                                        local->mdev->name, prev->dev->name);
1442                         continue;
1443                 }
1444                 rx.skb = skb_new;
1445                 rx.dev = prev->dev;
1446                 rx.sdata = prev;
1447                 ieee80211_invoke_rx_handlers(local, local->rx_handlers,
1448                                              &rx, sta);
1449                 prev = sdata;
1450         }
1451         if (prev) {
1452                 rx.skb = skb;
1453                 rx.dev = prev->dev;
1454                 rx.sdata = prev;
1455                 ieee80211_invoke_rx_handlers(local, local->rx_handlers,
1456                                              &rx, sta);
1457         } else
1458                 dev_kfree_skb(skb);
1459         read_unlock(&local->sub_if_lock);
1460
1461  end:
1462         if (sta)
1463                 sta_info_put(sta);
1464 }
1465 EXPORT_SYMBOL(__ieee80211_rx);
1466
1467 /* This is a version of the rx handler that can be called from hard irq
1468  * context. Post the skb on the queue and schedule the tasklet */
1469 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
1470                           struct ieee80211_rx_status *status)
1471 {
1472         struct ieee80211_local *local = hw_to_local(hw);
1473
1474         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
1475
1476         skb->dev = local->mdev;
1477         /* copy status into skb->cb for use by tasklet */
1478         memcpy(skb->cb, status, sizeof(*status));
1479         skb->pkt_type = IEEE80211_RX_MSG;
1480         skb_queue_tail(&local->skb_queue, skb);
1481         tasklet_schedule(&local->tasklet);
1482 }
1483 EXPORT_SYMBOL(ieee80211_rx_irqsafe);