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

   1 /*
   2  * Copyright 2002-2005, Instant802 Networks, Inc.
   3  * Copyright 2005-2006, Devicescape Software, Inc.
   4  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   5  * Copyright 2007       Johannes Berg <johannes@sipsolutions.net>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/skbuff.h>
  14 #include <linux/netdevice.h>
  15 #include <linux/etherdevice.h>
  16 #include <linux/rcupdate.h>
  17 #include <net/mac80211.h>
  18 #include <net/ieee80211_radiotap.h>
  19
  20 #include "ieee80211_i.h"
  21 #include "ieee80211_led.h"
  22 #include "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                 u8 padding_for_rxflags;
 149                 __le16 rx_flags;
 150         } __attribute__ ((packed)) *rthdr;
 151
 152         skb->dev = dev;
 153
 154         if (status->flag & RX_FLAG_RADIOTAP)
 155                 goto out;
 156
 157         if (skb_headroom(skb) < sizeof(*rthdr)) {
 158                 I802_DEBUG_INC(local->rx_expand_skb_head);
 159                 if (pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC)) {
 160                         dev_kfree_skb(skb);
 161                         return;
 162                 }
 163         }
 164
 165         rthdr = (struct ieee80211_rtap_hdr *) skb_push(skb, sizeof(*rthdr));
 166         memset(rthdr, 0, sizeof(*rthdr));
 167         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
 168         rthdr->hdr.it_present =
 169                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 170                             (1 << IEEE80211_RADIOTAP_RATE) |
 171                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
 172                             (1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL) |
 173                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
 174         rthdr->flags = local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS ?
 175                        IEEE80211_RADIOTAP_F_FCS : 0;
 176
 177         /* FIXME: when radiotap gets a 'bad PLCP' flag use it here */
 178         rthdr->rx_flags = 0;
 179         if (status->flag &
 180             (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 181                 rthdr->rx_flags |= cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS);
 182
 183         rate = ieee80211_get_rate(local, status->phymode, status->rate);
 184         if (rate)
 185                 rthdr->rate = rate->rate / 5;
 186
 187         rthdr->chan_freq = cpu_to_le16(status->freq);
 188         rthdr->chan_flags =
 189                 status->phymode == MODE_IEEE80211A ?
 190                 cpu_to_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ) :
 191                 cpu_to_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ);
 192         rthdr->antsignal = status->ssi;
 193
 194  out:
 195         dev->stats.rx_packets++;
 196         dev->stats.rx_bytes += skb->len;
 197
 198         skb_set_mac_header(skb, 0);
 199         skb->ip_summed = CHECKSUM_UNNECESSARY;
 200         skb->pkt_type = PACKET_OTHERHOST;
 201         skb->protocol = htons(ETH_P_802_2);
 202         memset(skb->cb, 0, sizeof(skb->cb));
 203         netif_rx(skb);
 204 }
 205
 206 static ieee80211_txrx_result
 207 ieee80211_rx_h_monitor(struct ieee80211_txrx_data *rx)
 208 {
 209         if (rx->sdata->type == IEEE80211_IF_TYPE_MNTR) {
 210                 ieee80211_rx_monitor(rx->dev, rx->skb, rx->u.rx.status);
 211                 return TXRX_QUEUED;
 212         }
 213
 214         /*
 215          * Drop frames with failed FCS/PLCP checksums here, they are only
 216          * relevant for monitor mode, the rest of the stack should never
 217          * see them.
 218          */
 219         if (rx->u.rx.status->flag &
 220             (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 221                 return TXRX_DROP;
 222
 223         if (rx->u.rx.status->flag & RX_FLAG_RADIOTAP)
 224                 skb_pull(rx->skb, ieee80211_get_radiotap_len(rx->skb->data));
 225
 226         return TXRX_CONTINUE;
 227 }
 228
 229 static ieee80211_txrx_result
 230 ieee80211_rx_h_passive_scan(struct ieee80211_txrx_data *rx)
 231 {
 232         struct ieee80211_local *local = rx->local;
 233         struct sk_buff *skb = rx->skb;
 234
 235         if (unlikely(local->sta_scanning != 0)) {
 236                 ieee80211_sta_rx_scan(rx->dev, skb, rx->u.rx.status);
 237                 return TXRX_QUEUED;
 238         }
 239
 240         if (unlikely(rx->flags & IEEE80211_TXRXD_RXIN_SCAN)) {
 241                 /* scanning finished during invoking of handlers */
 242                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
 243                 return TXRX_DROP;
 244         }
 245
 246         return TXRX_CONTINUE;
 247 }
 248
 249 static ieee80211_txrx_result
 250 ieee80211_rx_h_check(struct ieee80211_txrx_data *rx)
 251 {
 252         struct ieee80211_hdr *hdr;
 253         hdr = (struct ieee80211_hdr *) rx->skb->data;
 254
 255         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 256         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 257                 if (unlikely(rx->fc & IEEE80211_FCTL_RETRY &&
 258                              rx->sta->last_seq_ctrl[rx->u.rx.queue] ==
 259                              hdr->seq_ctrl)) {
 260                         if (rx->flags & IEEE80211_TXRXD_RXRA_MATCH) {
 261                                 rx->local->dot11FrameDuplicateCount++;
 262                                 rx->sta->num_duplicates++;
 263                         }
 264                         return TXRX_DROP;
 265                 } else
 266                         rx->sta->last_seq_ctrl[rx->u.rx.queue] = hdr->seq_ctrl;
 267         }
 268
 269         if ((rx->local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) &&
 270             rx->skb->len > FCS_LEN)
 271                 skb_trim(rx->skb, rx->skb->len - FCS_LEN);
 272
 273         if (unlikely(rx->skb->len < 16)) {
 274                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 275                 return TXRX_DROP;
 276         }
 277
 278         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 279                 rx->skb->pkt_type = PACKET_OTHERHOST;
 280         else if (compare_ether_addr(rx->dev->dev_addr, hdr->addr1) == 0)
 281                 rx->skb->pkt_type = PACKET_HOST;
 282         else if (is_multicast_ether_addr(hdr->addr1)) {
 283                 if (is_broadcast_ether_addr(hdr->addr1))
 284                         rx->skb->pkt_type = PACKET_BROADCAST;
 285                 else
 286                         rx->skb->pkt_type = PACKET_MULTICAST;
 287         } else
 288                 rx->skb->pkt_type = PACKET_OTHERHOST;
 289
 290         /* Drop disallowed frame classes based on STA auth/assoc state;
 291          * IEEE 802.11, Chap 5.5.
 292          *
 293          * 80211.o does filtering only based on association state, i.e., it
 294          * drops Class 3 frames from not associated stations. hostapd sends
 295          * deauth/disassoc frames when needed. In addition, hostapd is
 296          * responsible for filtering on both auth and assoc states.
 297          */
 298         if (unlikely(((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA ||
 299                       ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_CTL &&
 300                        (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PSPOLL)) &&
 301                      rx->sdata->type != IEEE80211_IF_TYPE_IBSS &&
 302                      (!rx->sta || !(rx->sta->flags & WLAN_STA_ASSOC)))) {
 303                 if ((!(rx->fc & IEEE80211_FCTL_FROMDS) &&
 304                      !(rx->fc & IEEE80211_FCTL_TODS) &&
 305                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA)
 306                     || !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
 307                         /* Drop IBSS frames and frames for other hosts
 308                          * silently. */
 309                         return TXRX_DROP;
 310                 }
 311
 312                 if (!rx->local->apdev)
 313                         return TXRX_DROP;
 314
 315                 ieee80211_rx_mgmt(rx->local, rx->skb, rx->u.rx.status,
 316                                   ieee80211_msg_sta_not_assoc);
 317                 return TXRX_QUEUED;
 318         }
 319
 320         return TXRX_CONTINUE;
 321 }
 322
 323
 324 static ieee80211_txrx_result
 325 ieee80211_rx_h_load_key(struct ieee80211_txrx_data *rx)
 326 {
 327         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 328         int keyidx;
 329         int hdrlen;
 330         struct ieee80211_key *stakey = NULL;
 331
 332         /*
 333          * Key selection 101
 334          *
 335          * There are three types of keys:
 336          *  - GTK (group keys)
 337          *  - PTK (pairwise keys)
 338          *  - STK (station-to-station pairwise keys)
 339          *
 340          * When selecting a key, we have to distinguish between multicast
 341          * (including broadcast) and unicast frames, the latter can only
 342          * use PTKs and STKs while the former always use GTKs. Unless, of
 343          * course, actual WEP keys ("pre-RSNA") are used, then unicast
 344          * frames can also use key indizes like GTKs. Hence, if we don't
 345          * have a PTK/STK we check the key index for a WEP key.
 346          *
 347          * Note that in a regular BSS, multicast frames are sent by the
 348          * AP only, associated stations unicast the frame to the AP first
 349          * which then multicasts it on their behalf.
 350          *
 351          * There is also a slight problem in IBSS mode: GTKs are negotiated
 352          * with each station, that is something we don't currently handle.
 353          * The spec seems to expect that one negotiates the same key with
 354          * every station but there's no such requirement; VLANs could be
 355          * possible.
 356          */
 357
 358         if (!(rx->fc & IEEE80211_FCTL_PROTECTED))
 359                 return TXRX_CONTINUE;
 360
 361         /*
 362          * No point in finding a key if the frame is neither
 363          * addressed to us nor a multicast frame.
 364          */
 365         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 366                 return TXRX_CONTINUE;
 367
 368         if (rx->sta)
 369                 stakey = rcu_dereference(rx->sta->key);
 370
 371         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
 372                 rx->key = stakey;
 373         } else {
 374                 /*
 375                  * The device doesn't give us the IV so we won't be
 376                  * able to look up the key. That's ok though, we
 377                  * don't need to decrypt the frame, we just won't
 378                  * be able to keep statistics accurate.
 379                  * Except for key threshold notifications, should
 380                  * we somehow allow the driver to tell us which key
 381                  * the hardware used if this flag is set?
 382                  */
 383                 if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) &&
 384                     (rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED))
 385                         return TXRX_CONTINUE;
 386
 387                 hdrlen = ieee80211_get_hdrlen(rx->fc);
 388
 389                 if (rx->skb->len < 8 + hdrlen)
 390                         return TXRX_DROP; /* TODO: count this? */
 391
 392                 /*
 393                  * no need to call ieee80211_wep_get_keyidx,
 394                  * it verifies a bunch of things we've done already
 395                  */
 396                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
 397
 398                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
 399
 400                 /*
 401                  * RSNA-protected unicast frames should always be sent with
 402                  * pairwise or station-to-station keys, but for WEP we allow
 403                  * using a key index as well.
 404                  */
 405                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
 406                     !is_multicast_ether_addr(hdr->addr1))
 407                         rx->key = NULL;
 408         }
 409
 410         if (rx->key) {
 411                 rx->key->tx_rx_count++;
 412                 /* TODO: add threshold stuff again */
 413         }
 414
 415         return TXRX_CONTINUE;
 416 }
 417
 418 static void ap_sta_ps_start(struct net_device *dev, struct sta_info *sta)
 419 {
 420         struct ieee80211_sub_if_data *sdata;
 421         DECLARE_MAC_BUF(mac);
 422
 423         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 424
 425         if (sdata->bss)
 426                 atomic_inc(&sdata->bss->num_sta_ps);
 427         sta->flags |= WLAN_STA_PS;
 428         sta->pspoll = 0;
 429 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 430         printk(KERN_DEBUG "%s: STA %s aid %d enters power save mode\n",
 431                dev->name, print_mac(mac, sta->addr), sta->aid);
 432 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 433 }
 434
 435 static int ap_sta_ps_end(struct net_device *dev, struct sta_info *sta)
 436 {
 437         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 438         struct sk_buff *skb;
 439         int sent = 0;
 440         struct ieee80211_sub_if_data *sdata;
 441         struct ieee80211_tx_packet_data *pkt_data;
 442         DECLARE_MAC_BUF(mac);
 443
 444         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 445         if (sdata->bss)
 446                 atomic_dec(&sdata->bss->num_sta_ps);
 447         sta->flags &= ~(WLAN_STA_PS | WLAN_STA_TIM);
 448         sta->pspoll = 0;
 449         if (!skb_queue_empty(&sta->ps_tx_buf)) {
 450                 if (local->ops->set_tim)
 451                         local->ops->set_tim(local_to_hw(local), sta->aid, 0);
 452                 if (sdata->bss)
 453                         bss_tim_clear(local, sdata->bss, sta->aid);
 454         }
 455 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 456         printk(KERN_DEBUG "%s: STA %s aid %d exits power save mode\n",
 457                dev->name, print_mac(mac, sta->addr), sta->aid);
 458 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 459         /* Send all buffered frames to the station */
 460         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
 461                 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 462                 sent++;
 463                 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
 464                 dev_queue_xmit(skb);
 465         }
 466         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
 467                 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 468                 local->total_ps_buffered--;
 469                 sent++;
 470 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 471                 printk(KERN_DEBUG "%s: STA %s aid %d send PS frame "
 472                        "since STA not sleeping anymore\n", dev->name,
 473                        print_mac(mac, sta->addr), sta->aid);
 474 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 475                 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
 476                 dev_queue_xmit(skb);
 477         }
 478
 479         return sent;
 480 }
 481
 482 static ieee80211_txrx_result
 483 ieee80211_rx_h_sta_process(struct ieee80211_txrx_data *rx)
 484 {
 485         struct sta_info *sta = rx->sta;
 486         struct net_device *dev = rx->dev;
 487         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 488
 489         if (!sta)
 490                 return TXRX_CONTINUE;
 491
 492         /* Update last_rx only for IBSS packets which are for the current
 493          * BSSID to avoid keeping the current IBSS network alive in cases where
 494          * other STAs are using different BSSID. */
 495         if (rx->sdata->type == IEEE80211_IF_TYPE_IBSS) {
 496                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len);
 497                 if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0)
 498                         sta->last_rx = jiffies;
 499         } else
 500         if (!is_multicast_ether_addr(hdr->addr1) ||
 501             rx->sdata->type == IEEE80211_IF_TYPE_STA) {
 502                 /* Update last_rx only for unicast frames in order to prevent
 503                  * the Probe Request frames (the only broadcast frames from a
 504                  * STA in infrastructure mode) from keeping a connection alive.
 505                  */
 506                 sta->last_rx = jiffies;
 507         }
 508
 509         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 510                 return TXRX_CONTINUE;
 511
 512         sta->rx_fragments++;
 513         sta->rx_bytes += rx->skb->len;
 514         sta->last_rssi = rx->u.rx.status->ssi;
 515         sta->last_signal = rx->u.rx.status->signal;
 516         sta->last_noise = rx->u.rx.status->noise;
 517
 518         if (!(rx->fc & IEEE80211_FCTL_MOREFRAGS)) {
 519                 /* Change STA power saving mode only in the end of a frame
 520                  * exchange sequence */
 521                 if ((sta->flags & WLAN_STA_PS) && !(rx->fc & IEEE80211_FCTL_PM))
 522                         rx->u.rx.sent_ps_buffered += ap_sta_ps_end(dev, sta);
 523                 else if (!(sta->flags & WLAN_STA_PS) &&
 524                          (rx->fc & IEEE80211_FCTL_PM))
 525                         ap_sta_ps_start(dev, sta);
 526         }
 527
 528         /* Drop data::nullfunc frames silently, since they are used only to
 529          * control station power saving mode. */
 530         if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 531             (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_NULLFUNC) {
 532                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
 533                 /* Update counter and free packet here to avoid counting this
 534                  * as a dropped packed. */
 535                 sta->rx_packets++;
 536                 dev_kfree_skb(rx->skb);
 537                 return TXRX_QUEUED;
 538         }
 539
 540         return TXRX_CONTINUE;
 541 } /* ieee80211_rx_h_sta_process */
 542
 543 static ieee80211_txrx_result
 544 ieee80211_rx_h_wep_weak_iv_detection(struct ieee80211_txrx_data *rx)
 545 {
 546         if (!rx->sta || !(rx->fc & IEEE80211_FCTL_PROTECTED) ||
 547             (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA ||
 548             !rx->key || rx->key->conf.alg != ALG_WEP ||
 549             !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 550                 return TXRX_CONTINUE;
 551
 552         /* Check for weak IVs, if hwaccel did not remove IV from the frame */
 553         if (!(rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED) ||
 554             !(rx->u.rx.status->flag & RX_FLAG_DECRYPTED))
 555                 if (ieee80211_wep_is_weak_iv(rx->skb, rx->key))
 556                         rx->sta->wep_weak_iv_count++;
 557
 558         return TXRX_CONTINUE;
 559 }
 560
 561 static ieee80211_txrx_result
 562 ieee80211_rx_h_wep_decrypt(struct ieee80211_txrx_data *rx)
 563 {
 564         if ((rx->key && rx->key->conf.alg != ALG_WEP) ||
 565             !(rx->fc & IEEE80211_FCTL_PROTECTED) ||
 566             ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
 567              ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
 568               (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)))
 569                 return TXRX_CONTINUE;
 570
 571         if (!rx->key) {
 572                 if (net_ratelimit())
 573                         printk(KERN_DEBUG "%s: RX WEP frame, but no key set\n",
 574                                rx->dev->name);
 575                 return TXRX_DROP;
 576         }
 577
 578         if (!(rx->u.rx.status->flag & RX_FLAG_DECRYPTED)) {
 579                 if (ieee80211_wep_decrypt(rx->local, rx->skb, rx->key)) {
 580                         if (net_ratelimit())
 581                                 printk(KERN_DEBUG "%s: RX WEP frame, decrypt "
 582                                        "failed\n", rx->dev->name);
 583                         return TXRX_DROP;
 584                 }
 585         } else if (!(rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED)) {
 586                 ieee80211_wep_remove_iv(rx->local, rx->skb, rx->key);
 587                 /* remove ICV */
 588                 skb_trim(rx->skb, rx->skb->len - 4);
 589         }
 590
 591         return TXRX_CONTINUE;
 592 }
 593
 594 static inline struct ieee80211_fragment_entry *
 595 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
 596                          unsigned int frag, unsigned int seq, int rx_queue,
 597                          struct sk_buff **skb)
 598 {
 599         struct ieee80211_fragment_entry *entry;
 600         int idx;
 601
 602         idx = sdata->fragment_next;
 603         entry = &sdata->fragments[sdata->fragment_next++];
 604         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
 605                 sdata->fragment_next = 0;
 606
 607         if (!skb_queue_empty(&entry->skb_list)) {
 608 #ifdef CONFIG_MAC80211_DEBUG
 609                 struct ieee80211_hdr *hdr =
 610                         (struct ieee80211_hdr *) entry->skb_list.next->data;
 611                 DECLARE_MAC_BUF(mac);
 612                 DECLARE_MAC_BUF(mac2);
 613                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
 614                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
 615                        "addr1=%s addr2=%s\n",
 616                        sdata->dev->name, idx,
 617                        jiffies - entry->first_frag_time, entry->seq,
 618                        entry->last_frag, print_mac(mac, hdr->addr1),
 619                        print_mac(mac2, hdr->addr2));
 620 #endif /* CONFIG_MAC80211_DEBUG */
 621                 __skb_queue_purge(&entry->skb_list);
 622         }
 623
 624         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
 625         *skb = NULL;
 626         entry->first_frag_time = jiffies;
 627         entry->seq = seq;
 628         entry->rx_queue = rx_queue;
 629         entry->last_frag = frag;
 630         entry->ccmp = 0;
 631         entry->extra_len = 0;
 632
 633         return entry;
 634 }
 635
 636 static inline struct ieee80211_fragment_entry *
 637 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
 638                           u16 fc, unsigned int frag, unsigned int seq,
 639                           int rx_queue, struct ieee80211_hdr *hdr)
 640 {
 641         struct ieee80211_fragment_entry *entry;
 642         int i, idx;
 643
 644         idx = sdata->fragment_next;
 645         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
 646                 struct ieee80211_hdr *f_hdr;
 647                 u16 f_fc;
 648
 649                 idx--;
 650                 if (idx < 0)
 651                         idx = IEEE80211_FRAGMENT_MAX - 1;
 652
 653                 entry = &sdata->fragments[idx];
 654                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
 655                     entry->rx_queue != rx_queue ||
 656                     entry->last_frag + 1 != frag)
 657                         continue;
 658
 659                 f_hdr = (struct ieee80211_hdr *) entry->skb_list.next->data;
 660                 f_fc = le16_to_cpu(f_hdr->frame_control);
 661
 662                 if ((fc & IEEE80211_FCTL_FTYPE) != (f_fc & IEEE80211_FCTL_FTYPE) ||
 663                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
 664                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
 665                         continue;
 666
 667                 if (entry->first_frag_time + 2 * HZ < jiffies) {
 668                         __skb_queue_purge(&entry->skb_list);
 669                         continue;
 670                 }
 671                 return entry;
 672         }
 673
 674         return NULL;
 675 }
 676
 677 static ieee80211_txrx_result
 678 ieee80211_rx_h_defragment(struct ieee80211_txrx_data *rx)
 679 {
 680         struct ieee80211_hdr *hdr;
 681         u16 sc;
 682         unsigned int frag, seq;
 683         struct ieee80211_fragment_entry *entry;
 684         struct sk_buff *skb;
 685         DECLARE_MAC_BUF(mac);
 686
 687         hdr = (struct ieee80211_hdr *) rx->skb->data;
 688         sc = le16_to_cpu(hdr->seq_ctrl);
 689         frag = sc & IEEE80211_SCTL_FRAG;
 690
 691         if (likely((!(rx->fc & IEEE80211_FCTL_MOREFRAGS) && frag == 0) ||
 692                    (rx->skb)->len < 24 ||
 693                    is_multicast_ether_addr(hdr->addr1))) {
 694                 /* not fragmented */
 695                 goto out;
 696         }
 697         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
 698
 699         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
 700
 701         if (frag == 0) {
 702                 /* This is the first fragment of a new frame. */
 703                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
 704                                                  rx->u.rx.queue, &(rx->skb));
 705                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
 706                     (rx->fc & IEEE80211_FCTL_PROTECTED)) {
 707                         /* Store CCMP PN so that we can verify that the next
 708                          * fragment has a sequential PN value. */
 709                         entry->ccmp = 1;
 710                         memcpy(entry->last_pn,
 711                                rx->key->u.ccmp.rx_pn[rx->u.rx.queue],
 712                                CCMP_PN_LEN);
 713                 }
 714                 return TXRX_QUEUED;
 715         }
 716
 717         /* This is a fragment for a frame that should already be pending in
 718          * fragment cache. Add this fragment to the end of the pending entry.
 719          */
 720         entry = ieee80211_reassemble_find(rx->sdata, rx->fc, frag, seq,
 721                                           rx->u.rx.queue, hdr);
 722         if (!entry) {
 723                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 724                 return TXRX_DROP;
 725         }
 726
 727         /* Verify that MPDUs within one MSDU have sequential PN values.
 728          * (IEEE 802.11i, 8.3.3.4.5) */
 729         if (entry->ccmp) {
 730                 int i;
 731                 u8 pn[CCMP_PN_LEN], *rpn;
 732                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
 733                         return TXRX_DROP;
 734                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
 735                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
 736                         pn[i]++;
 737                         if (pn[i])
 738                                 break;
 739                 }
 740                 rpn = rx->key->u.ccmp.rx_pn[rx->u.rx.queue];
 741                 if (memcmp(pn, rpn, CCMP_PN_LEN) != 0) {
 742                         if (net_ratelimit())
 743                                 printk(KERN_DEBUG "%s: defrag: CCMP PN not "
 744                                        "sequential A2=%s"
 745                                        " PN=%02x%02x%02x%02x%02x%02x "
 746                                        "(expected %02x%02x%02x%02x%02x%02x)\n",
 747                                        rx->dev->name, print_mac(mac, hdr->addr2),
 748                                        rpn[0], rpn[1], rpn[2], rpn[3], rpn[4],
 749                                        rpn[5], pn[0], pn[1], pn[2], pn[3],
 750                                        pn[4], pn[5]);
 751                         return TXRX_DROP;
 752                 }
 753                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
 754         }
 755
 756         skb_pull(rx->skb, ieee80211_get_hdrlen(rx->fc));
 757         __skb_queue_tail(&entry->skb_list, rx->skb);
 758         entry->last_frag = frag;
 759         entry->extra_len += rx->skb->len;
 760         if (rx->fc & IEEE80211_FCTL_MOREFRAGS) {
 761                 rx->skb = NULL;
 762                 return TXRX_QUEUED;
 763         }
 764
 765         rx->skb = __skb_dequeue(&entry->skb_list);
 766         if (skb_tailroom(rx->skb) < entry->extra_len) {
 767                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
 768                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
 769                                               GFP_ATOMIC))) {
 770                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 771                         __skb_queue_purge(&entry->skb_list);
 772                         return TXRX_DROP;
 773                 }
 774         }
 775         while ((skb = __skb_dequeue(&entry->skb_list))) {
 776                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
 777                 dev_kfree_skb(skb);
 778         }
 779
 780         /* Complete frame has been reassembled - process it now */
 781         rx->flags |= IEEE80211_TXRXD_FRAGMENTED;
 782
 783  out:
 784         if (rx->sta)
 785                 rx->sta->rx_packets++;
 786         if (is_multicast_ether_addr(hdr->addr1))
 787                 rx->local->dot11MulticastReceivedFrameCount++;
 788         else
 789                 ieee80211_led_rx(rx->local);
 790         return TXRX_CONTINUE;
 791 }
 792
 793 static ieee80211_txrx_result
 794 ieee80211_rx_h_ps_poll(struct ieee80211_txrx_data *rx)
 795 {
 796         struct sk_buff *skb;
 797         int no_pending_pkts;
 798         DECLARE_MAC_BUF(mac);
 799
 800         if (likely(!rx->sta ||
 801                    (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL ||
 802                    (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PSPOLL ||
 803                    !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)))
 804                 return TXRX_CONTINUE;
 805
 806         skb = skb_dequeue(&rx->sta->tx_filtered);
 807         if (!skb) {
 808                 skb = skb_dequeue(&rx->sta->ps_tx_buf);
 809                 if (skb)
 810                         rx->local->total_ps_buffered--;
 811         }
 812         no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
 813                 skb_queue_empty(&rx->sta->ps_tx_buf);
 814
 815         if (skb) {
 816                 struct ieee80211_hdr *hdr =
 817                         (struct ieee80211_hdr *) skb->data;
 818
 819                 /* tell TX path to send one frame even though the STA may
 820                  * still remain is PS mode after this frame exchange */
 821                 rx->sta->pspoll = 1;
 822
 823 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 824                 printk(KERN_DEBUG "STA %s aid %d: PS Poll (entries after %d)\n",
 825                        print_mac(mac, rx->sta->addr), rx->sta->aid,
 826                        skb_queue_len(&rx->sta->ps_tx_buf));
 827 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 828
 829                 /* Use MoreData flag to indicate whether there are more
 830                  * buffered frames for this STA */
 831                 if (no_pending_pkts) {
 832                         hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
 833                         rx->sta->flags &= ~WLAN_STA_TIM;
 834                 } else
 835                         hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
 836
 837                 dev_queue_xmit(skb);
 838
 839                 if (no_pending_pkts) {
 840                         if (rx->local->ops->set_tim)
 841                                 rx->local->ops->set_tim(local_to_hw(rx->local),
 842                                                        rx->sta->aid, 0);
 843                         if (rx->sdata->bss)
 844                                 bss_tim_clear(rx->local, rx->sdata->bss, rx->sta->aid);
 845                 }
 846 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 847         } else if (!rx->u.rx.sent_ps_buffered) {
 848                 printk(KERN_DEBUG "%s: STA %s sent PS Poll even "
 849                        "though there is no buffered frames for it\n",
 850                        rx->dev->name, print_mac(mac, rx->sta->addr));
 851 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 852
 853         }
 854
 855         /* Free PS Poll skb here instead of returning TXRX_DROP that would
 856          * count as an dropped frame. */
 857         dev_kfree_skb(rx->skb);
 858
 859         return TXRX_QUEUED;
 860 }
 861
 862 static ieee80211_txrx_result
 863 ieee80211_rx_h_remove_qos_control(struct ieee80211_txrx_data *rx)
 864 {
 865         u16 fc = rx->fc;
 866         u8 *data = rx->skb->data;
 867         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) data;
 868
 869         if (!WLAN_FC_IS_QOS_DATA(fc))
 870                 return TXRX_CONTINUE;
 871
 872         /* remove the qos control field, update frame type and meta-data */
 873         memmove(data + 2, data, ieee80211_get_hdrlen(fc) - 2);
 874         hdr = (struct ieee80211_hdr *) skb_pull(rx->skb, 2);
 875         /* change frame type to non QOS */
 876         rx->fc = fc &= ~IEEE80211_STYPE_QOS_DATA;
 877         hdr->frame_control = cpu_to_le16(fc);
 878
 879         return TXRX_CONTINUE;
 880 }
 881
 882 static ieee80211_txrx_result
 883 ieee80211_rx_h_802_1x_pae(struct ieee80211_txrx_data *rx)
 884 {
 885         if (rx->sdata->eapol && ieee80211_is_eapol(rx->skb) &&
 886             rx->sdata->type != IEEE80211_IF_TYPE_STA &&
 887             (rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
 888                 /* Pass both encrypted and unencrypted EAPOL frames to user
 889                  * space for processing. */
 890                 if (!rx->local->apdev)
 891                         return TXRX_DROP;
 892                 ieee80211_rx_mgmt(rx->local, rx->skb, rx->u.rx.status,
 893                                   ieee80211_msg_normal);
 894                 return TXRX_QUEUED;
 895         }
 896
 897         if (unlikely(rx->sdata->ieee802_1x &&
 898                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 899                      (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
 900                      (!rx->sta || !(rx->sta->flags & WLAN_STA_AUTHORIZED)) &&
 901                      !ieee80211_is_eapol(rx->skb))) {
 902 #ifdef CONFIG_MAC80211_DEBUG
 903                 struct ieee80211_hdr *hdr =
 904                         (struct ieee80211_hdr *) rx->skb->data;
 905                 DECLARE_MAC_BUF(mac);
 906                 printk(KERN_DEBUG "%s: dropped frame from %s"
 907                        " (unauthorized port)\n", rx->dev->name,
 908                        print_mac(mac, hdr->addr2));
 909 #endif /* CONFIG_MAC80211_DEBUG */
 910                 return TXRX_DROP;
 911         }
 912
 913         return TXRX_CONTINUE;
 914 }
 915
 916 static ieee80211_txrx_result
 917 ieee80211_rx_h_drop_unencrypted(struct ieee80211_txrx_data *rx)
 918 {
 919         /*
 920          * Pass through unencrypted frames if the hardware has
 921          * decrypted them already.
 922          */
 923         if (rx->u.rx.status->flag & RX_FLAG_DECRYPTED)
 924                 return TXRX_CONTINUE;
 925
 926         /* Drop unencrypted frames if key is set. */
 927         if (unlikely(!(rx->fc & IEEE80211_FCTL_PROTECTED) &&
 928                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 929                      (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
 930                      (rx->key || rx->sdata->drop_unencrypted) &&
 931                      (rx->sdata->eapol == 0 ||
 932                       !ieee80211_is_eapol(rx->skb)))) {
 933                 if (net_ratelimit())
 934                         printk(KERN_DEBUG "%s: RX non-WEP frame, but expected "
 935                                "encryption\n", rx->dev->name);
 936                 return TXRX_DROP;
 937         }
 938         return TXRX_CONTINUE;
 939 }
 940
 941 static ieee80211_txrx_result
 942 ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
 943 {
 944         struct net_device *dev = rx->dev;
 945         struct ieee80211_local *local = rx->local;
 946         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 947         u16 fc, hdrlen, ethertype;
 948         u8 *payload;
 949         u8 dst[ETH_ALEN];
 950         u8 src[ETH_ALEN];
 951         struct sk_buff *skb = rx->skb, *skb2;
 952         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 953         DECLARE_MAC_BUF(mac);
 954         DECLARE_MAC_BUF(mac2);
 955         DECLARE_MAC_BUF(mac3);
 956         DECLARE_MAC_BUF(mac4);
 957
 958         fc = rx->fc;
 959         if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
 960                 return TXRX_CONTINUE;
 961
 962         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
 963                 return TXRX_DROP;
 964
 965         hdrlen = ieee80211_get_hdrlen(fc);
 966
 967         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
 968          * header
 969          * IEEE 802.11 address fields:
 970          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
 971          *   0     0   DA    SA    BSSID n/a
 972          *   0     1   DA    BSSID SA    n/a
 973          *   1     0   BSSID SA    DA    n/a
 974          *   1     1   RA    TA    DA    SA
 975          */
 976
 977         switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
 978         case IEEE80211_FCTL_TODS:
 979                 /* BSSID SA DA */
 980                 memcpy(dst, hdr->addr3, ETH_ALEN);
 981                 memcpy(src, hdr->addr2, ETH_ALEN);
 982
 983                 if (unlikely(sdata->type != IEEE80211_IF_TYPE_AP &&
 984                              sdata->type != IEEE80211_IF_TYPE_VLAN)) {
 985                         if (net_ratelimit())
 986                                 printk(KERN_DEBUG "%s: dropped ToDS frame "
 987                                        "(BSSID=%s SA=%s DA=%s)\n",
 988                                        dev->name,
 989                                        print_mac(mac, hdr->addr1),
 990                                        print_mac(mac2, hdr->addr2),
 991                                        print_mac(mac3, hdr->addr3));
 992                         return TXRX_DROP;
 993                 }
 994                 break;
 995         case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
 996                 /* RA TA DA SA */
 997                 memcpy(dst, hdr->addr3, ETH_ALEN);
 998                 memcpy(src, hdr->addr4, ETH_ALEN);
 999
1000                 if (unlikely(sdata->type != IEEE80211_IF_TYPE_WDS)) {
1001                         if (net_ratelimit())
1002                                 printk(KERN_DEBUG "%s: dropped FromDS&ToDS "
1003                                        "frame (RA=%s TA=%s DA=%s SA=%s)\n",
1004                                        rx->dev->name,
1005                                        print_mac(mac, hdr->addr1),
1006                                        print_mac(mac2, hdr->addr2),
1007                                        print_mac(mac3, hdr->addr3),
1008                                        print_mac(mac4, hdr->addr4));
1009                         return TXRX_DROP;
1010                 }
1011                 break;
1012         case IEEE80211_FCTL_FROMDS:
1013                 /* DA BSSID SA */
1014                 memcpy(dst, hdr->addr1, ETH_ALEN);
1015                 memcpy(src, hdr->addr3, ETH_ALEN);
1016
1017                 if (sdata->type != IEEE80211_IF_TYPE_STA ||
1018                     (is_multicast_ether_addr(dst) &&
1019                      !compare_ether_addr(src, dev->dev_addr)))
1020                         return TXRX_DROP;
1021                 break;
1022         case 0:
1023                 /* DA SA BSSID */
1024                 memcpy(dst, hdr->addr1, ETH_ALEN);
1025                 memcpy(src, hdr->addr2, ETH_ALEN);
1026
1027                 if (sdata->type != IEEE80211_IF_TYPE_IBSS) {
1028                         if (net_ratelimit()) {
1029                                 printk(KERN_DEBUG "%s: dropped IBSS frame "
1030                                        "(DA=%s SA=%s BSSID=%s)\n",
1031                                        dev->name,
1032                                        print_mac(mac, hdr->addr1),
1033                                        print_mac(mac2, hdr->addr2),
1034                                        print_mac(mac3, hdr->addr3));
1035                         }
1036                         return TXRX_DROP;
1037                 }
1038                 break;
1039         }
1040
1041         payload = skb->data + hdrlen;
1042
1043         if (unlikely(skb->len - hdrlen < 8)) {
1044                 if (net_ratelimit()) {
1045                         printk(KERN_DEBUG "%s: RX too short data frame "
1046                                "payload\n", dev->name);
1047                 }
1048                 return TXRX_DROP;
1049         }
1050
1051         ethertype = (payload[6] << 8) | payload[7];
1052
1053         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1054                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1055                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1056                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1057                  * replace EtherType */
1058                 skb_pull(skb, hdrlen + 6);
1059                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1060                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1061         } else {
1062                 struct ethhdr *ehdr;
1063                 __be16 len;
1064                 skb_pull(skb, hdrlen);
1065                 len = htons(skb->len);
1066                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1067                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1068                 memcpy(ehdr->h_source, src, ETH_ALEN);
1069                 ehdr->h_proto = len;
1070         }
1071         skb->dev = dev;
1072
1073         skb2 = NULL;
1074
1075         dev->stats.rx_packets++;
1076         dev->stats.rx_bytes += skb->len;
1077
1078         if (local->bridge_packets && (sdata->type == IEEE80211_IF_TYPE_AP
1079             || sdata->type == IEEE80211_IF_TYPE_VLAN) &&
1080             (rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
1081                 if (is_multicast_ether_addr(skb->data)) {
1082                         /* send multicast frames both to higher layers in
1083                          * local net stack and back to the wireless media */
1084                         skb2 = skb_copy(skb, GFP_ATOMIC);
1085                         if (!skb2 && net_ratelimit())
1086                                 printk(KERN_DEBUG "%s: failed to clone "
1087                                        "multicast frame\n", dev->name);
1088                 } else {
1089                         struct sta_info *dsta;
1090                         dsta = sta_info_get(local, skb->data);
1091                         if (dsta && !dsta->dev) {
1092                                 if (net_ratelimit())
1093                                         printk(KERN_DEBUG "Station with null "
1094                                                "dev structure!\n");
1095                         } else if (dsta && dsta->dev == dev) {
1096                                 /* Destination station is associated to this
1097                                  * AP, so send the frame directly to it and
1098                                  * do not pass the frame to local net stack.
1099                                  */
1100                                 skb2 = skb;
1101                                 skb = NULL;
1102                         }
1103                         if (dsta)
1104                                 sta_info_put(dsta);
1105                 }
1106         }
1107
1108         if (skb) {
1109                 /* deliver to local stack */
1110                 skb->protocol = eth_type_trans(skb, dev);
1111                 memset(skb->cb, 0, sizeof(skb->cb));
1112                 netif_rx(skb);
1113         }
1114
1115         if (skb2) {
1116                 /* send to wireless media */
1117                 skb2->protocol = __constant_htons(ETH_P_802_3);
1118                 skb_set_network_header(skb2, 0);
1119                 skb_set_mac_header(skb2, 0);
1120                 dev_queue_xmit(skb2);
1121         }
1122
1123         return TXRX_QUEUED;
1124 }
1125
1126 static ieee80211_txrx_result
1127 ieee80211_rx_h_mgmt(struct ieee80211_txrx_data *rx)
1128 {
1129         struct ieee80211_sub_if_data *sdata;
1130
1131         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
1132                 return TXRX_DROP;
1133
1134         sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1135         if ((sdata->type == IEEE80211_IF_TYPE_STA ||
1136              sdata->type == IEEE80211_IF_TYPE_IBSS) &&
1137             !rx->local->user_space_mlme) {
1138                 ieee80211_sta_rx_mgmt(rx->dev, rx->skb, rx->u.rx.status);
1139         } else {
1140                 /* Management frames are sent to hostapd for processing */
1141                 if (!rx->local->apdev)
1142                         return TXRX_DROP;
1143                 ieee80211_rx_mgmt(rx->local, rx->skb, rx->u.rx.status,
1144                                   ieee80211_msg_normal);
1145         }
1146         return TXRX_QUEUED;
1147 }
1148
1149 static inline ieee80211_txrx_result __ieee80211_invoke_rx_handlers(
1150                                 struct ieee80211_local *local,
1151                                 ieee80211_rx_handler *handlers,
1152                                 struct ieee80211_txrx_data *rx,
1153                                 struct sta_info *sta)
1154 {
1155         ieee80211_rx_handler *handler;
1156         ieee80211_txrx_result res = TXRX_DROP;
1157
1158         for (handler = handlers; *handler != NULL; handler++) {
1159                 res = (*handler)(rx);
1160
1161                 switch (res) {
1162                 case TXRX_CONTINUE:
1163                         continue;
1164                 case TXRX_DROP:
1165                         I802_DEBUG_INC(local->rx_handlers_drop);
1166                         if (sta)
1167                                 sta->rx_dropped++;
1168                         break;
1169                 case TXRX_QUEUED:
1170                         I802_DEBUG_INC(local->rx_handlers_queued);
1171                         break;
1172                 }
1173                 break;
1174         }
1175
1176         if (res == TXRX_DROP)
1177                 dev_kfree_skb(rx->skb);
1178         return res;
1179 }
1180
1181 static inline void ieee80211_invoke_rx_handlers(struct ieee80211_local *local,
1182                                                 ieee80211_rx_handler *handlers,
1183                                                 struct ieee80211_txrx_data *rx,
1184                                                 struct sta_info *sta)
1185 {
1186         if (__ieee80211_invoke_rx_handlers(local, handlers, rx, sta) ==
1187             TXRX_CONTINUE)
1188                 dev_kfree_skb(rx->skb);
1189 }
1190
1191 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1192                                             struct ieee80211_hdr *hdr,
1193                                             struct sta_info *sta,
1194                                             struct ieee80211_txrx_data *rx)
1195 {
1196         int keyidx, hdrlen;
1197         DECLARE_MAC_BUF(mac);
1198         DECLARE_MAC_BUF(mac2);
1199
1200         hdrlen = ieee80211_get_hdrlen_from_skb(rx->skb);
1201         if (rx->skb->len >= hdrlen + 4)
1202                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1203         else
1204                 keyidx = -1;
1205
1206         if (net_ratelimit())
1207                 printk(KERN_DEBUG "%s: TKIP hwaccel reported Michael MIC "
1208                        "failure from %s to %s keyidx=%d\n",
1209                        dev->name, print_mac(mac, hdr->addr2),
1210                        print_mac(mac2, hdr->addr1), keyidx);
1211
1212         if (!sta) {
1213                 /*
1214                  * Some hardware seem to generate incorrect Michael MIC
1215                  * reports; ignore them to avoid triggering countermeasures.
1216                  */
1217                 if (net_ratelimit())
1218                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1219                                "error for unknown address %s\n",
1220                                dev->name, print_mac(mac, hdr->addr2));
1221                 goto ignore;
1222         }
1223
1224         if (!(rx->fc & IEEE80211_FCTL_PROTECTED)) {
1225                 if (net_ratelimit())
1226                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1227                                "error for a frame with no PROTECTED flag (src "
1228                                "%s)\n", dev->name, print_mac(mac, hdr->addr2));
1229                 goto ignore;
1230         }
1231
1232         if (rx->sdata->type == IEEE80211_IF_TYPE_AP && keyidx) {
1233                 /*
1234                  * APs with pairwise keys should never receive Michael MIC
1235                  * errors for non-zero keyidx because these are reserved for
1236                  * group keys and only the AP is sending real multicast
1237                  * frames in the BSS.
1238                  */
1239                 if (net_ratelimit())
1240                         printk(KERN_DEBUG "%s: ignored Michael MIC error for "
1241                                "a frame with non-zero keyidx (%d)"
1242                                " (src %s)\n", dev->name, keyidx,
1243                                print_mac(mac, hdr->addr2));
1244                 goto ignore;
1245         }
1246
1247         if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
1248             ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
1249              (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)) {
1250                 if (net_ratelimit())
1251                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1252                                "error for a frame that cannot be encrypted "
1253                                "(fc=0x%04x) (src %s)\n",
1254                                dev->name, rx->fc, print_mac(mac, hdr->addr2));
1255                 goto ignore;
1256         }
1257
1258         mac80211_ev_michael_mic_failure(rx->dev, keyidx, hdr);
1259  ignore:
1260         dev_kfree_skb(rx->skb);
1261         rx->skb = NULL;
1262 }
1263
1264 ieee80211_rx_handler ieee80211_rx_handlers[] =
1265 {
1266         ieee80211_rx_h_if_stats,
1267         ieee80211_rx_h_monitor,
1268         ieee80211_rx_h_passive_scan,
1269         ieee80211_rx_h_check,
1270         ieee80211_rx_h_load_key,
1271         ieee80211_rx_h_sta_process,
1272         ieee80211_rx_h_ccmp_decrypt,
1273         ieee80211_rx_h_tkip_decrypt,
1274         ieee80211_rx_h_wep_weak_iv_detection,
1275         ieee80211_rx_h_wep_decrypt,
1276         ieee80211_rx_h_defragment,
1277         ieee80211_rx_h_ps_poll,
1278         ieee80211_rx_h_michael_mic_verify,
1279         /* this must be after decryption - so header is counted in MPDU mic
1280          * must be before pae and data, so QOS_DATA format frames
1281          * are not passed to user space by these functions
1282          */
1283         ieee80211_rx_h_remove_qos_control,
1284         ieee80211_rx_h_802_1x_pae,
1285         ieee80211_rx_h_drop_unencrypted,
1286         ieee80211_rx_h_data,
1287         ieee80211_rx_h_mgmt,
1288         NULL
1289 };
1290
1291 /* main receive path */
1292
1293 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
1294                                 u8 *bssid, struct ieee80211_txrx_data *rx,
1295                                 struct ieee80211_hdr *hdr)
1296 {
1297         int multicast = is_multicast_ether_addr(hdr->addr1);
1298
1299         switch (sdata->type) {
1300         case IEEE80211_IF_TYPE_STA:
1301                 if (!bssid)
1302                         return 0;
1303                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1304                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1305                                 return 0;
1306                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1307                 } else if (!multicast &&
1308                            compare_ether_addr(sdata->dev->dev_addr,
1309                                               hdr->addr1) != 0) {
1310                         if (!(sdata->flags & IEEE80211_SDATA_PROMISC))
1311                                 return 0;
1312                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1313                 }
1314                 break;
1315         case IEEE80211_IF_TYPE_IBSS:
1316                 if (!bssid)
1317                         return 0;
1318                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1319                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1320                                 return 0;
1321                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1322                 } else if (!multicast &&
1323                            compare_ether_addr(sdata->dev->dev_addr,
1324                                               hdr->addr1) != 0) {
1325                         if (!(sdata->flags & IEEE80211_SDATA_PROMISC))
1326                                 return 0;
1327                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1328                 } else if (!rx->sta)
1329                         rx->sta = ieee80211_ibss_add_sta(sdata->dev, rx->skb,
1330                                                          bssid, hdr->addr2);
1331                 break;
1332         case IEEE80211_IF_TYPE_AP:
1333                 if (!bssid) {
1334                         if (compare_ether_addr(sdata->dev->dev_addr,
1335                                                hdr->addr1))
1336                                 return 0;
1337                 } else if (!ieee80211_bssid_match(bssid,
1338                                         sdata->dev->dev_addr)) {
1339                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1340                                 return 0;
1341                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1342                 }
1343                 if (sdata->dev == sdata->local->mdev &&
1344                     !(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1345                         /* do not receive anything via
1346                          * master device when not scanning */
1347                         return 0;
1348                 break;
1349         case IEEE80211_IF_TYPE_WDS:
1350                 if (bssid ||
1351                     (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
1352                         return 0;
1353                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
1354                         return 0;
1355                 break;
1356         }
1357
1358         return 1;
1359 }
1360
1361 /*
1362  * This is the receive path handler. It is called by a low level driver when an
1363  * 802.11 MPDU is received from the hardware.
1364  */
1365 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
1366                     struct ieee80211_rx_status *status)
1367 {
1368         struct ieee80211_local *local = hw_to_local(hw);
1369         struct ieee80211_sub_if_data *sdata;
1370         struct sta_info *sta;
1371         struct ieee80211_hdr *hdr;
1372         struct ieee80211_txrx_data rx;
1373         u16 type;
1374         int radiotap_len = 0, prepres;
1375         struct ieee80211_sub_if_data *prev = NULL;
1376         struct sk_buff *skb_new;
1377         u8 *bssid;
1378         int bogon;
1379
1380         if (status->flag & RX_FLAG_RADIOTAP) {
1381                 radiotap_len = ieee80211_get_radiotap_len(skb->data);
1382                 skb_pull(skb, radiotap_len);
1383         }
1384
1385         /*
1386          * key references are protected using RCU and this requires that
1387          * we are in a read-site RCU section during receive processing
1388          */
1389         rcu_read_lock();
1390
1391         hdr = (struct ieee80211_hdr *) skb->data;
1392         memset(&rx, 0, sizeof(rx));
1393         rx.skb = skb;
1394         rx.local = local;
1395
1396         rx.u.rx.status = status;
1397         rx.fc = skb->len >= 2 ? le16_to_cpu(hdr->frame_control) : 0;
1398         type = rx.fc & IEEE80211_FCTL_FTYPE;
1399
1400         bogon = status->flag & (RX_FLAG_FAILED_FCS_CRC |
1401                                 RX_FLAG_FAILED_PLCP_CRC);
1402
1403         if (!bogon && (type == IEEE80211_FTYPE_DATA ||
1404                        type == IEEE80211_FTYPE_MGMT))
1405                 local->dot11ReceivedFragmentCount++;
1406
1407         if (!bogon && skb->len >= 16) {
1408                 sta = rx.sta = sta_info_get(local, hdr->addr2);
1409                 if (sta) {
1410                         rx.dev = rx.sta->dev;
1411                         rx.sdata = IEEE80211_DEV_TO_SUB_IF(rx.dev);
1412                 }
1413         } else
1414                 sta = rx.sta = NULL;
1415
1416         if ((status->flag & RX_FLAG_MMIC_ERROR)) {
1417                 ieee80211_rx_michael_mic_report(local->mdev, hdr, sta, &rx);
1418                 goto end;
1419         }
1420
1421         if (unlikely(local->sta_scanning))
1422                 rx.flags |= IEEE80211_TXRXD_RXIN_SCAN;
1423
1424         if (__ieee80211_invoke_rx_handlers(local, local->rx_pre_handlers, &rx,
1425                                            sta) != TXRX_CONTINUE)
1426                 goto end;
1427         skb = rx.skb;
1428
1429         skb_push(skb, radiotap_len);
1430         if (sta && !(sta->flags & (WLAN_STA_WDS | WLAN_STA_ASSOC_AP)) &&
1431             !local->iff_promiscs && !is_multicast_ether_addr(hdr->addr1)) {
1432                 rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
1433                 ieee80211_invoke_rx_handlers(local, local->rx_handlers, &rx,
1434                                              rx.sta);
1435                 sta_info_put(sta);
1436                 rcu_read_unlock();
1437                 return;
1438         }
1439
1440         bssid = ieee80211_get_bssid(hdr, skb->len - radiotap_len);
1441
1442         read_lock(&local->sub_if_lock);
1443         list_for_each_entry(sdata, &local->sub_if_list, list) {
1444                 rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
1445
1446                 if (!netif_running(sdata->dev))
1447                         continue;
1448
1449                 prepres = prepare_for_handlers(sdata, bssid, &rx, hdr);
1450                 /* prepare_for_handlers can change sta */
1451                 sta = rx.sta;
1452
1453                 if (!prepres)
1454                         continue;
1455
1456                 /*
1457                  * frame is destined for this interface, but if it's not
1458                  * also for the previous one we handle that after the
1459                  * loop to avoid copying the SKB once too much
1460                  */
1461
1462                 if (!prev) {
1463                         prev = sdata;
1464                         continue;
1465                 }
1466
1467                 /*
1468                  * frame was destined for the previous interface
1469                  * so invoke RX handlers for it
1470                  */
1471
1472                 skb_new = skb_copy(skb, GFP_ATOMIC);
1473                 if (!skb_new) {
1474                         if (net_ratelimit())
1475                                 printk(KERN_DEBUG "%s: failed to copy "
1476                                        "multicast frame for %s",
1477                                        wiphy_name(local->hw.wiphy),
1478                                        prev->dev->name);
1479                         continue;
1480                 }
1481                 rx.skb = skb_new;
1482                 rx.dev = prev->dev;
1483                 rx.sdata = prev;
1484                 ieee80211_invoke_rx_handlers(local, local->rx_handlers,
1485                                              &rx, sta);
1486                 prev = sdata;
1487         }
1488         if (prev) {
1489                 rx.skb = skb;
1490                 rx.dev = prev->dev;
1491                 rx.sdata = prev;
1492                 ieee80211_invoke_rx_handlers(local, local->rx_handlers,
1493                                              &rx, sta);
1494         } else
1495                 dev_kfree_skb(skb);
1496         read_unlock(&local->sub_if_lock);
1497
1498  end:
1499         rcu_read_unlock();
1500
1501         if (sta)
1502                 sta_info_put(sta);
1503 }
1504 EXPORT_SYMBOL(__ieee80211_rx);
1505
1506 /* This is a version of the rx handler that can be called from hard irq
1507  * context. Post the skb on the queue and schedule the tasklet */
1508 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
1509                           struct ieee80211_rx_status *status)
1510 {
1511         struct ieee80211_local *local = hw_to_local(hw);
1512
1513         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
1514
1515         skb->dev = local->mdev;
1516         /* copy status into skb->cb for use by tasklet */
1517         memcpy(skb->cb, status, sizeof(*status));
1518         skb->pkt_type = IEEE80211_RX_MSG;
1519         skb_queue_tail(&local->skb_queue, skb);
1520         tasklet_schedule(&local->tasklet);
1521 }
1522 EXPORT_SYMBOL(ieee80211_rx_irqsafe);