git.oblomov.eu Git - linux-2.6/blob - net/mac80211/rx.c

   1 /*
   2  * Copyright 2002-2005, Instant802 Networks, Inc.
   3  * Copyright 2005-2006, Devicescape Software, Inc.
   4  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   5  * Copyright 2007       Johannes Berg <johannes@sipsolutions.net>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/skbuff.h>
  14 #include <linux/netdevice.h>
  15 #include <linux/etherdevice.h>
  16 #include <linux/rcupdate.h>
  17 #include <net/mac80211.h>
  18 #include <net/ieee80211_radiotap.h>
  19
  20 #include "ieee80211_i.h"
  21 #include "ieee80211_led.h"
  22 #include "wep.h"
  23 #include "wpa.h"
  24 #include "tkip.h"
  25 #include "wme.h"
  26
  27 u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
  28                                 struct tid_ampdu_rx *tid_agg_rx,
  29                                 struct sk_buff *skb, u16 mpdu_seq_num,
  30                                 int bar_req);
  31 /*
  32  * monitor mode reception
  33  *
  34  * This function cleans up the SKB, i.e. it removes all the stuff
  35  * only useful for monitoring.
  36  */
  37 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
  38                                            struct sk_buff *skb,
  39                                            int rtap_len)
  40 {
  41         skb_pull(skb, rtap_len);
  42
  43         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
  44                 if (likely(skb->len > FCS_LEN))
  45                         skb_trim(skb, skb->len - FCS_LEN);
  46                 else {
  47                         /* driver bug */
  48                         WARN_ON(1);
  49                         dev_kfree_skb(skb);
  50                         skb = NULL;
  51                 }
  52         }
  53
  54         return skb;
  55 }
  56
  57 static inline int should_drop_frame(struct ieee80211_rx_status *status,
  58                                     struct sk_buff *skb,
  59                                     int present_fcs_len,
  60                                     int radiotap_len)
  61 {
  62         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
  63
  64         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
  65                 return 1;
  66         if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len))
  67                 return 1;
  68         if (((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_FTYPE)) ==
  69                         cpu_to_le16(IEEE80211_FTYPE_CTL)) &&
  70             ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE)) !=
  71                         cpu_to_le16(IEEE80211_STYPE_PSPOLL)) &&
  72             ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE)) !=
  73                         cpu_to_le16(IEEE80211_STYPE_BACK_REQ)))
  74                 return 1;
  75         return 0;
  76 }
  77
  78 /*
  79  * This function copies a received frame to all monitor interfaces and
  80  * returns a cleaned-up SKB that no longer includes the FCS nor the
  81  * radiotap header the driver might have added.
  82  */
  83 static struct sk_buff *
  84 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
  85                      struct ieee80211_rx_status *status)
  86 {
  87         struct ieee80211_sub_if_data *sdata;
  88         struct ieee80211_rate *rate;
  89         int needed_headroom = 0;
  90         struct ieee80211_radiotap_header *rthdr;
  91         __le64 *rttsft = NULL;
  92         struct ieee80211_rtap_fixed_data {
  93                 u8 flags;
  94                 u8 rate;
  95                 __le16 chan_freq;
  96                 __le16 chan_flags;
  97                 u8 antsignal;
  98                 u8 padding_for_rxflags;
  99                 __le16 rx_flags;
 100         } __attribute__ ((packed)) *rtfixed;
 101         struct sk_buff *skb, *skb2;
 102         struct net_device *prev_dev = NULL;
 103         int present_fcs_len = 0;
 104         int rtap_len = 0;
 105
 106         /*
 107          * First, we may need to make a copy of the skb because
 108          *  (1) we need to modify it for radiotap (if not present), and
 109          *  (2) the other RX handlers will modify the skb we got.
 110          *
 111          * We don't need to, of course, if we aren't going to return
 112          * the SKB because it has a bad FCS/PLCP checksum.
 113          */
 114         if (status->flag & RX_FLAG_RADIOTAP)
 115                 rtap_len = ieee80211_get_radiotap_len(origskb->data);
 116         else
 117                 /* room for radiotap header, always present fields and TSFT */
 118                 needed_headroom = sizeof(*rthdr) + sizeof(*rtfixed) + 8;
 119
 120         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 121                 present_fcs_len = FCS_LEN;
 122
 123         if (!local->monitors) {
 124                 if (should_drop_frame(status, origskb, present_fcs_len,
 125                                       rtap_len)) {
 126                         dev_kfree_skb(origskb);
 127                         return NULL;
 128                 }
 129
 130                 return remove_monitor_info(local, origskb, rtap_len);
 131         }
 132
 133         if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) {
 134                 /* only need to expand headroom if necessary */
 135                 skb = origskb;
 136                 origskb = NULL;
 137
 138                 /*
 139                  * This shouldn't trigger often because most devices have an
 140                  * RX header they pull before we get here, and that should
 141                  * be big enough for our radiotap information. We should
 142                  * probably export the length to drivers so that we can have
 143                  * them allocate enough headroom to start with.
 144                  */
 145                 if (skb_headroom(skb) < needed_headroom &&
 146                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
 147                         dev_kfree_skb(skb);
 148                         return NULL;
 149                 }
 150         } else {
 151                 /*
 152                  * Need to make a copy and possibly remove radiotap header
 153                  * and FCS from the original.
 154                  */
 155                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
 156
 157                 origskb = remove_monitor_info(local, origskb, rtap_len);
 158
 159                 if (!skb)
 160                         return origskb;
 161         }
 162
 163         /* if necessary, prepend radiotap information */
 164         if (!(status->flag & RX_FLAG_RADIOTAP)) {
 165                 rtfixed = (void *) skb_push(skb, sizeof(*rtfixed));
 166                 rtap_len = sizeof(*rthdr) + sizeof(*rtfixed);
 167                 if (status->flag & RX_FLAG_TSFT) {
 168                         rttsft = (void *) skb_push(skb, sizeof(*rttsft));
 169                         rtap_len += 8;
 170                 }
 171                 rthdr = (void *) skb_push(skb, sizeof(*rthdr));
 172                 memset(rthdr, 0, sizeof(*rthdr));
 173                 memset(rtfixed, 0, sizeof(*rtfixed));
 174                 rthdr->it_present =
 175                         cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 176                                     (1 << IEEE80211_RADIOTAP_RATE) |
 177                                     (1 << IEEE80211_RADIOTAP_CHANNEL) |
 178                                     (1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL) |
 179                                     (1 << IEEE80211_RADIOTAP_RX_FLAGS));
 180                 rtfixed->flags = 0;
 181                 if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 182                         rtfixed->flags |= IEEE80211_RADIOTAP_F_FCS;
 183
 184                 if (rttsft) {
 185                         *rttsft = cpu_to_le64(status->mactime);
 186                         rthdr->it_present |=
 187                                 cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
 188                 }
 189
 190                 /* FIXME: when radiotap gets a 'bad PLCP' flag use it here */
 191                 rtfixed->rx_flags = 0;
 192                 if (status->flag &
 193                     (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 194                         rtfixed->rx_flags |=
 195                                 cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS);
 196
 197                 rate = ieee80211_get_rate(local, status->phymode,
 198                                           status->rate);
 199                 if (rate)
 200                         rtfixed->rate = rate->rate / 5;
 201
 202                 rtfixed->chan_freq = cpu_to_le16(status->freq);
 203
 204                 if (status->phymode == MODE_IEEE80211A)
 205                         rtfixed->chan_flags =
 206                                 cpu_to_le16(IEEE80211_CHAN_OFDM |
 207                                             IEEE80211_CHAN_5GHZ);
 208                 else
 209                         rtfixed->chan_flags =
 210                                 cpu_to_le16(IEEE80211_CHAN_DYN |
 211                                             IEEE80211_CHAN_2GHZ);
 212
 213                 rtfixed->antsignal = status->ssi;
 214                 rthdr->it_len = cpu_to_le16(rtap_len);
 215         }
 216
 217         skb_reset_mac_header(skb);
 218         skb->ip_summed = CHECKSUM_UNNECESSARY;
 219         skb->pkt_type = PACKET_OTHERHOST;
 220         skb->protocol = htons(ETH_P_802_2);
 221
 222         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 223                 if (!netif_running(sdata->dev))
 224                         continue;
 225
 226                 if (sdata->vif.type != IEEE80211_IF_TYPE_MNTR)
 227                         continue;
 228
 229                 if (prev_dev) {
 230                         skb2 = skb_clone(skb, GFP_ATOMIC);
 231                         if (skb2) {
 232                                 skb2->dev = prev_dev;
 233                                 netif_rx(skb2);
 234                         }
 235                 }
 236
 237                 prev_dev = sdata->dev;
 238                 sdata->dev->stats.rx_packets++;
 239                 sdata->dev->stats.rx_bytes += skb->len;
 240         }
 241
 242         if (prev_dev) {
 243                 skb->dev = prev_dev;
 244                 netif_rx(skb);
 245         } else
 246                 dev_kfree_skb(skb);
 247
 248         return origskb;
 249 }
 250
 251
 252 /* pre-rx handlers
 253  *
 254  * these don't have dev/sdata fields in the rx data
 255  * The sta value should also not be used because it may
 256  * be NULL even though a STA (in IBSS mode) will be added.
 257  */
 258
 259 static ieee80211_txrx_result
 260 ieee80211_rx_h_parse_qos(struct ieee80211_txrx_data *rx)
 261 {
 262         u8 *data = rx->skb->data;
 263         int tid;
 264
 265         /* does the frame have a qos control field? */
 266         if (WLAN_FC_IS_QOS_DATA(rx->fc)) {
 267                 u8 *qc = data + ieee80211_get_hdrlen(rx->fc) - QOS_CONTROL_LEN;
 268                 /* frame has qos control */
 269                 tid = qc[0] & QOS_CONTROL_TID_MASK;
 270                 if (qc[0] & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
 271                         rx->flags |= IEEE80211_TXRXD_RX_AMSDU;
 272                 else
 273                         rx->flags &= ~IEEE80211_TXRXD_RX_AMSDU;
 274         } else {
 275                 if (unlikely((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT)) {
 276                         /* Separate TID for management frames */
 277                         tid = NUM_RX_DATA_QUEUES - 1;
 278                 } else {
 279                         /* no qos control present */
 280                         tid = 0; /* 802.1d - Best Effort */
 281                 }
 282         }
 283
 284         I802_DEBUG_INC(rx->local->wme_rx_queue[tid]);
 285         /* only a debug counter, sta might not be assigned properly yet */
 286         if (rx->sta)
 287                 I802_DEBUG_INC(rx->sta->wme_rx_queue[tid]);
 288
 289         rx->u.rx.queue = tid;
 290         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 291          * For now, set skb->priority to 0 for other cases. */
 292         rx->skb->priority = (tid > 7) ? 0 : tid;
 293
 294         return TXRX_CONTINUE;
 295 }
 296
 297
 298 static u32 ieee80211_rx_load_stats(struct ieee80211_local *local,
 299                               struct sk_buff *skb,
 300                               struct ieee80211_rx_status *status)
 301 {
 302         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 303         u32 load = 0, hdrtime;
 304         struct ieee80211_rate *rate;
 305         struct ieee80211_hw_mode *mode = local->hw.conf.mode;
 306         int i;
 307
 308         /* Estimate total channel use caused by this frame */
 309
 310         if (unlikely(mode->num_rates < 0))
 311                 return TXRX_CONTINUE;
 312
 313         rate = &mode->rates[0];
 314         for (i = 0; i < mode->num_rates; i++) {
 315                 if (mode->rates[i].val == status->rate) {
 316                         rate = &mode->rates[i];
 317                         break;
 318                 }
 319         }
 320
 321         /* 1 bit at 1 Mbit/s takes 1 usec; in channel_use values,
 322          * 1 usec = 1/8 * (1080 / 10) = 13.5 */
 323
 324         if (mode->mode == MODE_IEEE80211A ||
 325             (mode->mode == MODE_IEEE80211G &&
 326              rate->flags & IEEE80211_RATE_ERP))
 327                 hdrtime = CHAN_UTIL_HDR_SHORT;
 328         else
 329                 hdrtime = CHAN_UTIL_HDR_LONG;
 330
 331         load = hdrtime;
 332         if (!is_multicast_ether_addr(hdr->addr1))
 333                 load += hdrtime;
 334
 335         load += skb->len * rate->rate_inv;
 336
 337         /* Divide channel_use by 8 to avoid wrapping around the counter */
 338         load >>= CHAN_UTIL_SHIFT;
 339
 340         return load;
 341 }
 342
 343 ieee80211_rx_handler ieee80211_rx_pre_handlers[] =
 344 {
 345         ieee80211_rx_h_parse_qos,
 346         NULL
 347 };
 348
 349 /* rx handlers */
 350
 351 static ieee80211_txrx_result
 352 ieee80211_rx_h_if_stats(struct ieee80211_txrx_data *rx)
 353 {
 354         if (rx->sta)
 355                 rx->sta->channel_use_raw += rx->u.rx.load;
 356         rx->sdata->channel_use_raw += rx->u.rx.load;
 357         return TXRX_CONTINUE;
 358 }
 359
 360 static ieee80211_txrx_result
 361 ieee80211_rx_h_passive_scan(struct ieee80211_txrx_data *rx)
 362 {
 363         struct ieee80211_local *local = rx->local;
 364         struct sk_buff *skb = rx->skb;
 365
 366         if (unlikely(local->sta_hw_scanning))
 367                 return ieee80211_sta_rx_scan(rx->dev, skb, rx->u.rx.status);
 368
 369         if (unlikely(local->sta_sw_scanning)) {
 370                 /* drop all the other packets during a software scan anyway */
 371                 if (ieee80211_sta_rx_scan(rx->dev, skb, rx->u.rx.status)
 372                     != TXRX_QUEUED)
 373                         dev_kfree_skb(skb);
 374                 return TXRX_QUEUED;
 375         }
 376
 377         if (unlikely(rx->flags & IEEE80211_TXRXD_RXIN_SCAN)) {
 378                 /* scanning finished during invoking of handlers */
 379                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
 380                 return TXRX_DROP;
 381         }
 382
 383         return TXRX_CONTINUE;
 384 }
 385
 386 static ieee80211_txrx_result
 387 ieee80211_rx_h_check(struct ieee80211_txrx_data *rx)
 388 {
 389         struct ieee80211_hdr *hdr;
 390         hdr = (struct ieee80211_hdr *) rx->skb->data;
 391
 392         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 393         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 394                 if (unlikely(rx->fc & IEEE80211_FCTL_RETRY &&
 395                              rx->sta->last_seq_ctrl[rx->u.rx.queue] ==
 396                              hdr->seq_ctrl)) {
 397                         if (rx->flags & IEEE80211_TXRXD_RXRA_MATCH) {
 398                                 rx->local->dot11FrameDuplicateCount++;
 399                                 rx->sta->num_duplicates++;
 400                         }
 401                         return TXRX_DROP;
 402                 } else
 403                         rx->sta->last_seq_ctrl[rx->u.rx.queue] = hdr->seq_ctrl;
 404         }
 405
 406         if (unlikely(rx->skb->len < 16)) {
 407                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 408                 return TXRX_DROP;
 409         }
 410
 411         /* Drop disallowed frame classes based on STA auth/assoc state;
 412          * IEEE 802.11, Chap 5.5.
 413          *
 414          * 80211.o does filtering only based on association state, i.e., it
 415          * drops Class 3 frames from not associated stations. hostapd sends
 416          * deauth/disassoc frames when needed. In addition, hostapd is
 417          * responsible for filtering on both auth and assoc states.
 418          */
 419         if (unlikely(((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA ||
 420                       ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_CTL &&
 421                        (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PSPOLL)) &&
 422                      rx->sdata->vif.type != IEEE80211_IF_TYPE_IBSS &&
 423                      (!rx->sta || !(rx->sta->flags & WLAN_STA_ASSOC)))) {
 424                 if ((!(rx->fc & IEEE80211_FCTL_FROMDS) &&
 425                      !(rx->fc & IEEE80211_FCTL_TODS) &&
 426                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA)
 427                     || !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
 428                         /* Drop IBSS frames and frames for other hosts
 429                          * silently. */
 430                         return TXRX_DROP;
 431                 }
 432
 433                 return TXRX_DROP;
 434         }
 435
 436         return TXRX_CONTINUE;
 437 }
 438
 439
 440 static ieee80211_txrx_result
 441 ieee80211_rx_h_decrypt(struct ieee80211_txrx_data *rx)
 442 {
 443         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 444         int keyidx;
 445         int hdrlen;
 446         ieee80211_txrx_result result = TXRX_DROP;
 447         struct ieee80211_key *stakey = NULL;
 448
 449         /*
 450          * Key selection 101
 451          *
 452          * There are three types of keys:
 453          *  - GTK (group keys)
 454          *  - PTK (pairwise keys)
 455          *  - STK (station-to-station pairwise keys)
 456          *
 457          * When selecting a key, we have to distinguish between multicast
 458          * (including broadcast) and unicast frames, the latter can only
 459          * use PTKs and STKs while the former always use GTKs. Unless, of
 460          * course, actual WEP keys ("pre-RSNA") are used, then unicast
 461          * frames can also use key indizes like GTKs. Hence, if we don't
 462          * have a PTK/STK we check the key index for a WEP key.
 463          *
 464          * Note that in a regular BSS, multicast frames are sent by the
 465          * AP only, associated stations unicast the frame to the AP first
 466          * which then multicasts it on their behalf.
 467          *
 468          * There is also a slight problem in IBSS mode: GTKs are negotiated
 469          * with each station, that is something we don't currently handle.
 470          * The spec seems to expect that one negotiates the same key with
 471          * every station but there's no such requirement; VLANs could be
 472          * possible.
 473          */
 474
 475         if (!(rx->fc & IEEE80211_FCTL_PROTECTED))
 476                 return TXRX_CONTINUE;
 477
 478         /*
 479          * No point in finding a key and decrypting if the frame is neither
 480          * addressed to us nor a multicast frame.
 481          */
 482         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 483                 return TXRX_CONTINUE;
 484
 485         if (rx->sta)
 486                 stakey = rcu_dereference(rx->sta->key);
 487
 488         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
 489                 rx->key = stakey;
 490         } else {
 491                 /*
 492                  * The device doesn't give us the IV so we won't be
 493                  * able to look up the key. That's ok though, we
 494                  * don't need to decrypt the frame, we just won't
 495                  * be able to keep statistics accurate.
 496                  * Except for key threshold notifications, should
 497                  * we somehow allow the driver to tell us which key
 498                  * the hardware used if this flag is set?
 499                  */
 500                 if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) &&
 501                     (rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED))
 502                         return TXRX_CONTINUE;
 503
 504                 hdrlen = ieee80211_get_hdrlen(rx->fc);
 505
 506                 if (rx->skb->len < 8 + hdrlen)
 507                         return TXRX_DROP; /* TODO: count this? */
 508
 509                 /*
 510                  * no need to call ieee80211_wep_get_keyidx,
 511                  * it verifies a bunch of things we've done already
 512                  */
 513                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
 514
 515                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
 516
 517                 /*
 518                  * RSNA-protected unicast frames should always be sent with
 519                  * pairwise or station-to-station keys, but for WEP we allow
 520                  * using a key index as well.
 521                  */
 522                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
 523                     !is_multicast_ether_addr(hdr->addr1))
 524                         rx->key = NULL;
 525         }
 526
 527         if (rx->key) {
 528                 rx->key->tx_rx_count++;
 529                 /* TODO: add threshold stuff again */
 530         } else {
 531 #ifdef CONFIG_MAC80211_DEBUG
 532                 if (net_ratelimit())
 533                         printk(KERN_DEBUG "%s: RX protected frame,"
 534                                " but have no key\n", rx->dev->name);
 535 #endif /* CONFIG_MAC80211_DEBUG */
 536                 return TXRX_DROP;
 537         }
 538
 539         /* Check for weak IVs if possible */
 540         if (rx->sta && rx->key->conf.alg == ALG_WEP &&
 541             ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) &&
 542             (!(rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED) ||
 543              !(rx->u.rx.status->flag & RX_FLAG_DECRYPTED)) &&
 544             ieee80211_wep_is_weak_iv(rx->skb, rx->key))
 545                 rx->sta->wep_weak_iv_count++;
 546
 547         switch (rx->key->conf.alg) {
 548         case ALG_WEP:
 549                 result = ieee80211_crypto_wep_decrypt(rx);
 550                 break;
 551         case ALG_TKIP:
 552                 result = ieee80211_crypto_tkip_decrypt(rx);
 553                 break;
 554         case ALG_CCMP:
 555                 result = ieee80211_crypto_ccmp_decrypt(rx);
 556                 break;
 557         }
 558
 559         /* either the frame has been decrypted or will be dropped */
 560         rx->u.rx.status->flag |= RX_FLAG_DECRYPTED;
 561
 562         return result;
 563 }
 564
 565 static void ap_sta_ps_start(struct net_device *dev, struct sta_info *sta)
 566 {
 567         struct ieee80211_sub_if_data *sdata;
 568         DECLARE_MAC_BUF(mac);
 569
 570         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 571
 572         if (sdata->bss)
 573                 atomic_inc(&sdata->bss->num_sta_ps);
 574         sta->flags |= WLAN_STA_PS;
 575         sta->pspoll = 0;
 576 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 577         printk(KERN_DEBUG "%s: STA %s aid %d enters power save mode\n",
 578                dev->name, print_mac(mac, sta->addr), sta->aid);
 579 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 580 }
 581
 582 static int ap_sta_ps_end(struct net_device *dev, struct sta_info *sta)
 583 {
 584         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 585         struct sk_buff *skb;
 586         int sent = 0;
 587         struct ieee80211_sub_if_data *sdata;
 588         struct ieee80211_tx_packet_data *pkt_data;
 589         DECLARE_MAC_BUF(mac);
 590
 591         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 592         if (sdata->bss)
 593                 atomic_dec(&sdata->bss->num_sta_ps);
 594         sta->flags &= ~(WLAN_STA_PS | WLAN_STA_TIM);
 595         sta->pspoll = 0;
 596         if (!skb_queue_empty(&sta->ps_tx_buf)) {
 597                 if (local->ops->set_tim)
 598                         local->ops->set_tim(local_to_hw(local), sta->aid, 0);
 599                 if (sdata->bss)
 600                         bss_tim_clear(local, sdata->bss, sta->aid);
 601         }
 602 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 603         printk(KERN_DEBUG "%s: STA %s aid %d exits power save mode\n",
 604                dev->name, print_mac(mac, sta->addr), sta->aid);
 605 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 606         /* Send all buffered frames to the station */
 607         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
 608                 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 609                 sent++;
 610                 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
 611                 dev_queue_xmit(skb);
 612         }
 613         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
 614                 pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 615                 local->total_ps_buffered--;
 616                 sent++;
 617 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 618                 printk(KERN_DEBUG "%s: STA %s aid %d send PS frame "
 619                        "since STA not sleeping anymore\n", dev->name,
 620                        print_mac(mac, sta->addr), sta->aid);
 621 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 622                 pkt_data->flags |= IEEE80211_TXPD_REQUEUE;
 623                 dev_queue_xmit(skb);
 624         }
 625
 626         return sent;
 627 }
 628
 629 static ieee80211_txrx_result
 630 ieee80211_rx_h_sta_process(struct ieee80211_txrx_data *rx)
 631 {
 632         struct sta_info *sta = rx->sta;
 633         struct net_device *dev = rx->dev;
 634         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 635
 636         if (!sta)
 637                 return TXRX_CONTINUE;
 638
 639         /* Update last_rx only for IBSS packets which are for the current
 640          * BSSID to avoid keeping the current IBSS network alive in cases where
 641          * other STAs are using different BSSID. */
 642         if (rx->sdata->vif.type == IEEE80211_IF_TYPE_IBSS) {
 643                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
 644                                                 IEEE80211_IF_TYPE_IBSS);
 645                 if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0)
 646                         sta->last_rx = jiffies;
 647         } else
 648         if (!is_multicast_ether_addr(hdr->addr1) ||
 649             rx->sdata->vif.type == IEEE80211_IF_TYPE_STA) {
 650                 /* Update last_rx only for unicast frames in order to prevent
 651                  * the Probe Request frames (the only broadcast frames from a
 652                  * STA in infrastructure mode) from keeping a connection alive.
 653                  */
 654                 sta->last_rx = jiffies;
 655         }
 656
 657         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
 658                 return TXRX_CONTINUE;
 659
 660         sta->rx_fragments++;
 661         sta->rx_bytes += rx->skb->len;
 662         sta->last_rssi = rx->u.rx.status->ssi;
 663         sta->last_signal = rx->u.rx.status->signal;
 664         sta->last_noise = rx->u.rx.status->noise;
 665
 666         if (!(rx->fc & IEEE80211_FCTL_MOREFRAGS)) {
 667                 /* Change STA power saving mode only in the end of a frame
 668                  * exchange sequence */
 669                 if ((sta->flags & WLAN_STA_PS) && !(rx->fc & IEEE80211_FCTL_PM))
 670                         rx->u.rx.sent_ps_buffered += ap_sta_ps_end(dev, sta);
 671                 else if (!(sta->flags & WLAN_STA_PS) &&
 672                          (rx->fc & IEEE80211_FCTL_PM))
 673                         ap_sta_ps_start(dev, sta);
 674         }
 675
 676         /* Drop data::nullfunc frames silently, since they are used only to
 677          * control station power saving mode. */
 678         if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 679             (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_NULLFUNC) {
 680                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
 681                 /* Update counter and free packet here to avoid counting this
 682                  * as a dropped packed. */
 683                 sta->rx_packets++;
 684                 dev_kfree_skb(rx->skb);
 685                 return TXRX_QUEUED;
 686         }
 687
 688         return TXRX_CONTINUE;
 689 } /* ieee80211_rx_h_sta_process */
 690
 691 static inline struct ieee80211_fragment_entry *
 692 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
 693                          unsigned int frag, unsigned int seq, int rx_queue,
 694                          struct sk_buff **skb)
 695 {
 696         struct ieee80211_fragment_entry *entry;
 697         int idx;
 698
 699         idx = sdata->fragment_next;
 700         entry = &sdata->fragments[sdata->fragment_next++];
 701         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
 702                 sdata->fragment_next = 0;
 703
 704         if (!skb_queue_empty(&entry->skb_list)) {
 705 #ifdef CONFIG_MAC80211_DEBUG
 706                 struct ieee80211_hdr *hdr =
 707                         (struct ieee80211_hdr *) entry->skb_list.next->data;
 708                 DECLARE_MAC_BUF(mac);
 709                 DECLARE_MAC_BUF(mac2);
 710                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
 711                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
 712                        "addr1=%s addr2=%s\n",
 713                        sdata->dev->name, idx,
 714                        jiffies - entry->first_frag_time, entry->seq,
 715                        entry->last_frag, print_mac(mac, hdr->addr1),
 716                        print_mac(mac2, hdr->addr2));
 717 #endif /* CONFIG_MAC80211_DEBUG */
 718                 __skb_queue_purge(&entry->skb_list);
 719         }
 720
 721         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
 722         *skb = NULL;
 723         entry->first_frag_time = jiffies;
 724         entry->seq = seq;
 725         entry->rx_queue = rx_queue;
 726         entry->last_frag = frag;
 727         entry->ccmp = 0;
 728         entry->extra_len = 0;
 729
 730         return entry;
 731 }
 732
 733 static inline struct ieee80211_fragment_entry *
 734 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
 735                           u16 fc, unsigned int frag, unsigned int seq,
 736                           int rx_queue, struct ieee80211_hdr *hdr)
 737 {
 738         struct ieee80211_fragment_entry *entry;
 739         int i, idx;
 740
 741         idx = sdata->fragment_next;
 742         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
 743                 struct ieee80211_hdr *f_hdr;
 744                 u16 f_fc;
 745
 746                 idx--;
 747                 if (idx < 0)
 748                         idx = IEEE80211_FRAGMENT_MAX - 1;
 749
 750                 entry = &sdata->fragments[idx];
 751                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
 752                     entry->rx_queue != rx_queue ||
 753                     entry->last_frag + 1 != frag)
 754                         continue;
 755
 756                 f_hdr = (struct ieee80211_hdr *) entry->skb_list.next->data;
 757                 f_fc = le16_to_cpu(f_hdr->frame_control);
 758
 759                 if ((fc & IEEE80211_FCTL_FTYPE) != (f_fc & IEEE80211_FCTL_FTYPE) ||
 760                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
 761                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
 762                         continue;
 763
 764                 if (entry->first_frag_time + 2 * HZ < jiffies) {
 765                         __skb_queue_purge(&entry->skb_list);
 766                         continue;
 767                 }
 768                 return entry;
 769         }
 770
 771         return NULL;
 772 }
 773
 774 static ieee80211_txrx_result
 775 ieee80211_rx_h_defragment(struct ieee80211_txrx_data *rx)
 776 {
 777         struct ieee80211_hdr *hdr;
 778         u16 sc;
 779         unsigned int frag, seq;
 780         struct ieee80211_fragment_entry *entry;
 781         struct sk_buff *skb;
 782         DECLARE_MAC_BUF(mac);
 783
 784         hdr = (struct ieee80211_hdr *) rx->skb->data;
 785         sc = le16_to_cpu(hdr->seq_ctrl);
 786         frag = sc & IEEE80211_SCTL_FRAG;
 787
 788         if (likely((!(rx->fc & IEEE80211_FCTL_MOREFRAGS) && frag == 0) ||
 789                    (rx->skb)->len < 24 ||
 790                    is_multicast_ether_addr(hdr->addr1))) {
 791                 /* not fragmented */
 792                 goto out;
 793         }
 794         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
 795
 796         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
 797
 798         if (frag == 0) {
 799                 /* This is the first fragment of a new frame. */
 800                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
 801                                                  rx->u.rx.queue, &(rx->skb));
 802                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
 803                     (rx->fc & IEEE80211_FCTL_PROTECTED)) {
 804                         /* Store CCMP PN so that we can verify that the next
 805                          * fragment has a sequential PN value. */
 806                         entry->ccmp = 1;
 807                         memcpy(entry->last_pn,
 808                                rx->key->u.ccmp.rx_pn[rx->u.rx.queue],
 809                                CCMP_PN_LEN);
 810                 }
 811                 return TXRX_QUEUED;
 812         }
 813
 814         /* This is a fragment for a frame that should already be pending in
 815          * fragment cache. Add this fragment to the end of the pending entry.
 816          */
 817         entry = ieee80211_reassemble_find(rx->sdata, rx->fc, frag, seq,
 818                                           rx->u.rx.queue, hdr);
 819         if (!entry) {
 820                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 821                 return TXRX_DROP;
 822         }
 823
 824         /* Verify that MPDUs within one MSDU have sequential PN values.
 825          * (IEEE 802.11i, 8.3.3.4.5) */
 826         if (entry->ccmp) {
 827                 int i;
 828                 u8 pn[CCMP_PN_LEN], *rpn;
 829                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
 830                         return TXRX_DROP;
 831                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
 832                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
 833                         pn[i]++;
 834                         if (pn[i])
 835                                 break;
 836                 }
 837                 rpn = rx->key->u.ccmp.rx_pn[rx->u.rx.queue];
 838                 if (memcmp(pn, rpn, CCMP_PN_LEN) != 0) {
 839                         if (net_ratelimit())
 840                                 printk(KERN_DEBUG "%s: defrag: CCMP PN not "
 841                                        "sequential A2=%s"
 842                                        " PN=%02x%02x%02x%02x%02x%02x "
 843                                        "(expected %02x%02x%02x%02x%02x%02x)\n",
 844                                        rx->dev->name, print_mac(mac, hdr->addr2),
 845                                        rpn[0], rpn[1], rpn[2], rpn[3], rpn[4],
 846                                        rpn[5], pn[0], pn[1], pn[2], pn[3],
 847                                        pn[4], pn[5]);
 848                         return TXRX_DROP;
 849                 }
 850                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
 851         }
 852
 853         skb_pull(rx->skb, ieee80211_get_hdrlen(rx->fc));
 854         __skb_queue_tail(&entry->skb_list, rx->skb);
 855         entry->last_frag = frag;
 856         entry->extra_len += rx->skb->len;
 857         if (rx->fc & IEEE80211_FCTL_MOREFRAGS) {
 858                 rx->skb = NULL;
 859                 return TXRX_QUEUED;
 860         }
 861
 862         rx->skb = __skb_dequeue(&entry->skb_list);
 863         if (skb_tailroom(rx->skb) < entry->extra_len) {
 864                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
 865                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
 866                                               GFP_ATOMIC))) {
 867                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 868                         __skb_queue_purge(&entry->skb_list);
 869                         return TXRX_DROP;
 870                 }
 871         }
 872         while ((skb = __skb_dequeue(&entry->skb_list))) {
 873                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
 874                 dev_kfree_skb(skb);
 875         }
 876
 877         /* Complete frame has been reassembled - process it now */
 878         rx->flags |= IEEE80211_TXRXD_FRAGMENTED;
 879
 880  out:
 881         if (rx->sta)
 882                 rx->sta->rx_packets++;
 883         if (is_multicast_ether_addr(hdr->addr1))
 884                 rx->local->dot11MulticastReceivedFrameCount++;
 885         else
 886                 ieee80211_led_rx(rx->local);
 887         return TXRX_CONTINUE;
 888 }
 889
 890 static ieee80211_txrx_result
 891 ieee80211_rx_h_ps_poll(struct ieee80211_txrx_data *rx)
 892 {
 893         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
 894         struct sk_buff *skb;
 895         int no_pending_pkts;
 896         DECLARE_MAC_BUF(mac);
 897
 898         if (likely(!rx->sta ||
 899                    (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL ||
 900                    (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PSPOLL ||
 901                    !(rx->flags & IEEE80211_TXRXD_RXRA_MATCH)))
 902                 return TXRX_CONTINUE;
 903
 904         if ((sdata->vif.type != IEEE80211_IF_TYPE_AP) &&
 905             (sdata->vif.type != IEEE80211_IF_TYPE_VLAN))
 906                 return TXRX_DROP;
 907
 908         skb = skb_dequeue(&rx->sta->tx_filtered);
 909         if (!skb) {
 910                 skb = skb_dequeue(&rx->sta->ps_tx_buf);
 911                 if (skb)
 912                         rx->local->total_ps_buffered--;
 913         }
 914         no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
 915                 skb_queue_empty(&rx->sta->ps_tx_buf);
 916
 917         if (skb) {
 918                 struct ieee80211_hdr *hdr =
 919                         (struct ieee80211_hdr *) skb->data;
 920
 921                 /* tell TX path to send one frame even though the STA may
 922                  * still remain is PS mode after this frame exchange */
 923                 rx->sta->pspoll = 1;
 924
 925 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 926                 printk(KERN_DEBUG "STA %s aid %d: PS Poll (entries after %d)\n",
 927                        print_mac(mac, rx->sta->addr), rx->sta->aid,
 928                        skb_queue_len(&rx->sta->ps_tx_buf));
 929 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 930
 931                 /* Use MoreData flag to indicate whether there are more
 932                  * buffered frames for this STA */
 933                 if (no_pending_pkts) {
 934                         hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
 935                         rx->sta->flags &= ~WLAN_STA_TIM;
 936                 } else
 937                         hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
 938
 939                 dev_queue_xmit(skb);
 940
 941                 if (no_pending_pkts) {
 942                         if (rx->local->ops->set_tim)
 943                                 rx->local->ops->set_tim(local_to_hw(rx->local),
 944                                                        rx->sta->aid, 0);
 945                         if (rx->sdata->bss)
 946                                 bss_tim_clear(rx->local, rx->sdata->bss, rx->sta->aid);
 947                 }
 948 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 949         } else if (!rx->u.rx.sent_ps_buffered) {
 950                 printk(KERN_DEBUG "%s: STA %s sent PS Poll even "
 951                        "though there is no buffered frames for it\n",
 952                        rx->dev->name, print_mac(mac, rx->sta->addr));
 953 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 954
 955         }
 956
 957         /* Free PS Poll skb here instead of returning TXRX_DROP that would
 958          * count as an dropped frame. */
 959         dev_kfree_skb(rx->skb);
 960
 961         return TXRX_QUEUED;
 962 }
 963
 964 static ieee80211_txrx_result
 965 ieee80211_rx_h_remove_qos_control(struct ieee80211_txrx_data *rx)
 966 {
 967         u16 fc = rx->fc;
 968         u8 *data = rx->skb->data;
 969         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) data;
 970
 971         if (!WLAN_FC_IS_QOS_DATA(fc))
 972                 return TXRX_CONTINUE;
 973
 974         /* remove the qos control field, update frame type and meta-data */
 975         memmove(data + 2, data, ieee80211_get_hdrlen(fc) - 2);
 976         hdr = (struct ieee80211_hdr *) skb_pull(rx->skb, 2);
 977         /* change frame type to non QOS */
 978         rx->fc = fc &= ~IEEE80211_STYPE_QOS_DATA;
 979         hdr->frame_control = cpu_to_le16(fc);
 980
 981         return TXRX_CONTINUE;
 982 }
 983
 984 static int
 985 ieee80211_802_1x_port_control(struct ieee80211_txrx_data *rx)
 986 {
 987         if (unlikely(rx->sdata->ieee802_1x_pac &&
 988                      (!rx->sta || !(rx->sta->flags & WLAN_STA_AUTHORIZED)))) {
 989 #ifdef CONFIG_MAC80211_DEBUG
 990                 printk(KERN_DEBUG "%s: dropped frame "
 991                        "(unauthorized port)\n", rx->dev->name);
 992 #endif /* CONFIG_MAC80211_DEBUG */
 993                 return -EACCES;
 994         }
 995
 996         return 0;
 997 }
 998
 999 static int
1000 ieee80211_drop_unencrypted(struct ieee80211_txrx_data *rx)
1001 {
1002         /*
1003          * Pass through unencrypted frames if the hardware has
1004          * decrypted them already.
1005          */
1006         if (rx->u.rx.status->flag & RX_FLAG_DECRYPTED)
1007                 return 0;
1008
1009         /* Drop unencrypted frames if key is set. */
1010         if (unlikely(!(rx->fc & IEEE80211_FCTL_PROTECTED) &&
1011                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
1012                      (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
1013                      (rx->key || rx->sdata->drop_unencrypted))) {
1014                 if (net_ratelimit())
1015                         printk(KERN_DEBUG "%s: RX non-WEP frame, but expected "
1016                                "encryption\n", rx->dev->name);
1017                 return -EACCES;
1018         }
1019         return 0;
1020 }
1021
1022 static int
1023 ieee80211_data_to_8023(struct ieee80211_txrx_data *rx)
1024 {
1025         struct net_device *dev = rx->dev;
1026         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
1027         u16 fc, hdrlen, ethertype;
1028         u8 *payload;
1029         u8 dst[ETH_ALEN];
1030         u8 src[ETH_ALEN];
1031         struct sk_buff *skb = rx->skb;
1032         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1033         DECLARE_MAC_BUF(mac);
1034         DECLARE_MAC_BUF(mac2);
1035         DECLARE_MAC_BUF(mac3);
1036         DECLARE_MAC_BUF(mac4);
1037
1038         fc = rx->fc;
1039
1040         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1041                 return -1;
1042
1043         hdrlen = ieee80211_get_hdrlen(fc);
1044
1045         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
1046          * header
1047          * IEEE 802.11 address fields:
1048          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
1049          *   0     0   DA    SA    BSSID n/a
1050          *   0     1   DA    BSSID SA    n/a
1051          *   1     0   BSSID SA    DA    n/a
1052          *   1     1   RA    TA    DA    SA
1053          */
1054
1055         switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
1056         case IEEE80211_FCTL_TODS:
1057                 /* BSSID SA DA */
1058                 memcpy(dst, hdr->addr3, ETH_ALEN);
1059                 memcpy(src, hdr->addr2, ETH_ALEN);
1060
1061                 if (unlikely(sdata->vif.type != IEEE80211_IF_TYPE_AP &&
1062                              sdata->vif.type != IEEE80211_IF_TYPE_VLAN)) {
1063                         if (net_ratelimit())
1064                                 printk(KERN_DEBUG "%s: dropped ToDS frame "
1065                                        "(BSSID=%s SA=%s DA=%s)\n",
1066                                        dev->name,
1067                                        print_mac(mac, hdr->addr1),
1068                                        print_mac(mac2, hdr->addr2),
1069                                        print_mac(mac3, hdr->addr3));
1070                         return -1;
1071                 }
1072                 break;
1073         case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
1074                 /* RA TA DA SA */
1075                 memcpy(dst, hdr->addr3, ETH_ALEN);
1076                 memcpy(src, hdr->addr4, ETH_ALEN);
1077
1078                 if (unlikely(sdata->vif.type != IEEE80211_IF_TYPE_WDS)) {
1079                         if (net_ratelimit())
1080                                 printk(KERN_DEBUG "%s: dropped FromDS&ToDS "
1081                                        "frame (RA=%s TA=%s DA=%s SA=%s)\n",
1082                                        rx->dev->name,
1083                                        print_mac(mac, hdr->addr1),
1084                                        print_mac(mac2, hdr->addr2),
1085                                        print_mac(mac3, hdr->addr3),
1086                                        print_mac(mac4, hdr->addr4));
1087                         return -1;
1088                 }
1089                 break;
1090         case IEEE80211_FCTL_FROMDS:
1091                 /* DA BSSID SA */
1092                 memcpy(dst, hdr->addr1, ETH_ALEN);
1093                 memcpy(src, hdr->addr3, ETH_ALEN);
1094
1095                 if (sdata->vif.type != IEEE80211_IF_TYPE_STA ||
1096                     (is_multicast_ether_addr(dst) &&
1097                      !compare_ether_addr(src, dev->dev_addr)))
1098                         return -1;
1099                 break;
1100         case 0:
1101                 /* DA SA BSSID */
1102                 memcpy(dst, hdr->addr1, ETH_ALEN);
1103                 memcpy(src, hdr->addr2, ETH_ALEN);
1104
1105                 if (sdata->vif.type != IEEE80211_IF_TYPE_IBSS) {
1106                         if (net_ratelimit()) {
1107                                 printk(KERN_DEBUG "%s: dropped IBSS frame "
1108                                        "(DA=%s SA=%s BSSID=%s)\n",
1109                                        dev->name,
1110                                        print_mac(mac, hdr->addr1),
1111                                        print_mac(mac2, hdr->addr2),
1112                                        print_mac(mac3, hdr->addr3));
1113                         }
1114                         return -1;
1115                 }
1116                 break;
1117         }
1118
1119         if (unlikely(skb->len - hdrlen < 8)) {
1120                 if (net_ratelimit()) {
1121                         printk(KERN_DEBUG "%s: RX too short data frame "
1122                                "payload\n", dev->name);
1123                 }
1124                 return -1;
1125         }
1126
1127         payload = skb->data + hdrlen;
1128         ethertype = (payload[6] << 8) | payload[7];
1129
1130         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1131                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1132                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1133                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1134                  * replace EtherType */
1135                 skb_pull(skb, hdrlen + 6);
1136                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1137                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1138         } else {
1139                 struct ethhdr *ehdr;
1140                 __be16 len;
1141
1142                 skb_pull(skb, hdrlen);
1143                 len = htons(skb->len);
1144                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1145                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1146                 memcpy(ehdr->h_source, src, ETH_ALEN);
1147                 ehdr->h_proto = len;
1148         }
1149         return 0;
1150 }
1151
1152 /*
1153  * requires that rx->skb is a frame with ethernet header
1154  */
1155 static bool ieee80211_frame_allowed(struct ieee80211_txrx_data *rx)
1156 {
1157         static const u8 pae_group_addr[ETH_ALEN]
1158                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1159         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1160
1161         /*
1162          * Allow EAPOL frames to us/the PAE group address regardless
1163          * of whether the frame was encrypted or not.
1164          */
1165         if (ehdr->h_proto == htons(ETH_P_PAE) &&
1166             (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
1167              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1168                 return true;
1169
1170         if (ieee80211_802_1x_port_control(rx) ||
1171             ieee80211_drop_unencrypted(rx))
1172                 return false;
1173
1174         return true;
1175 }
1176
1177 /*
1178  * requires that rx->skb is a frame with ethernet header
1179  */
1180 static void
1181 ieee80211_deliver_skb(struct ieee80211_txrx_data *rx)
1182 {
1183         struct net_device *dev = rx->dev;
1184         struct ieee80211_local *local = rx->local;
1185         struct sk_buff *skb, *xmit_skb;
1186         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1187         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1188         struct sta_info *dsta;
1189
1190         skb = rx->skb;
1191         xmit_skb = NULL;
1192
1193         if (local->bridge_packets && (sdata->vif.type == IEEE80211_IF_TYPE_AP ||
1194                                       sdata->vif.type == IEEE80211_IF_TYPE_VLAN) &&
1195             (rx->flags & IEEE80211_TXRXD_RXRA_MATCH)) {
1196                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1197                         /*
1198                          * send multicast frames both to higher layers in
1199                          * local net stack and back to the wireless medium
1200                          */
1201                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1202                         if (!xmit_skb && net_ratelimit())
1203                                 printk(KERN_DEBUG "%s: failed to clone "
1204                                        "multicast frame\n", dev->name);
1205                 } else {
1206                         dsta = sta_info_get(local, skb->data);
1207                         if (dsta && dsta->dev == dev) {
1208                                 /*
1209                                  * The destination station is associated to
1210                                  * this AP (in this VLAN), so send the frame
1211                                  * directly to it and do not pass it to local
1212                                  * net stack.
1213                                  */
1214                                 xmit_skb = skb;
1215                                 skb = NULL;
1216                         }
1217                         if (dsta)
1218                                 sta_info_put(dsta);
1219                 }
1220         }
1221
1222         if (skb) {
1223                 /* deliver to local stack */
1224                 skb->protocol = eth_type_trans(skb, dev);
1225                 memset(skb->cb, 0, sizeof(skb->cb));
1226                 netif_rx(skb);
1227         }
1228
1229         if (xmit_skb) {
1230                 /* send to wireless media */
1231                 xmit_skb->protocol = htons(ETH_P_802_3);
1232                 skb_reset_network_header(xmit_skb);
1233                 skb_reset_mac_header(xmit_skb);
1234                 dev_queue_xmit(xmit_skb);
1235         }
1236 }
1237
1238 static ieee80211_txrx_result
1239 ieee80211_rx_h_amsdu(struct ieee80211_txrx_data *rx)
1240 {
1241         struct net_device *dev = rx->dev;
1242         struct ieee80211_local *local = rx->local;
1243         u16 fc, ethertype;
1244         u8 *payload;
1245         struct sk_buff *skb = rx->skb, *frame = NULL;
1246         const struct ethhdr *eth;
1247         int remaining, err;
1248         u8 dst[ETH_ALEN];
1249         u8 src[ETH_ALEN];
1250         DECLARE_MAC_BUF(mac);
1251
1252         fc = rx->fc;
1253         if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
1254                 return TXRX_CONTINUE;
1255
1256         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1257                 return TXRX_DROP;
1258
1259         if (!(rx->flags & IEEE80211_TXRXD_RX_AMSDU))
1260                 return TXRX_CONTINUE;
1261
1262         err = ieee80211_data_to_8023(rx);
1263         if (unlikely(err))
1264                 return TXRX_DROP;
1265
1266         skb->dev = dev;
1267
1268         dev->stats.rx_packets++;
1269         dev->stats.rx_bytes += skb->len;
1270
1271         /* skip the wrapping header */
1272         eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
1273         if (!eth)
1274                 return TXRX_DROP;
1275
1276         while (skb != frame) {
1277                 u8 padding;
1278                 __be16 len = eth->h_proto;
1279                 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
1280
1281                 remaining = skb->len;
1282                 memcpy(dst, eth->h_dest, ETH_ALEN);
1283                 memcpy(src, eth->h_source, ETH_ALEN);
1284
1285                 padding = ((4 - subframe_len) & 0x3);
1286                 /* the last MSDU has no padding */
1287                 if (subframe_len > remaining) {
1288                         printk(KERN_DEBUG "%s: wrong buffer size", dev->name);
1289                         return TXRX_DROP;
1290                 }
1291
1292                 skb_pull(skb, sizeof(struct ethhdr));
1293                 /* if last subframe reuse skb */
1294                 if (remaining <= subframe_len + padding)
1295                         frame = skb;
1296                 else {
1297                         frame = dev_alloc_skb(local->hw.extra_tx_headroom +
1298                                               subframe_len);
1299
1300                         if (frame == NULL)
1301                                 return TXRX_DROP;
1302
1303                         skb_reserve(frame, local->hw.extra_tx_headroom +
1304                                     sizeof(struct ethhdr));
1305                         memcpy(skb_put(frame, ntohs(len)), skb->data,
1306                                 ntohs(len));
1307
1308                         eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
1309                                                         padding);
1310                         if (!eth) {
1311                                 printk(KERN_DEBUG "%s: wrong buffer size ",
1312                                        dev->name);
1313                                 dev_kfree_skb(frame);
1314                                 return TXRX_DROP;
1315                         }
1316                 }
1317
1318                 skb_reset_network_header(frame);
1319                 frame->dev = dev;
1320                 frame->priority = skb->priority;
1321                 rx->skb = frame;
1322
1323                 payload = frame->data;
1324                 ethertype = (payload[6] << 8) | payload[7];
1325
1326                 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1327                             ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1328                            compare_ether_addr(payload,
1329                                               bridge_tunnel_header) == 0)) {
1330                         /* remove RFC1042 or Bridge-Tunnel
1331                          * encapsulation and replace EtherType */
1332                         skb_pull(frame, 6);
1333                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1334                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1335                 } else {
1336                         memcpy(skb_push(frame, sizeof(__be16)),
1337                                &len, sizeof(__be16));
1338                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1339                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1340                 }
1341
1342                 if (!ieee80211_frame_allowed(rx)) {
1343                         if (skb == frame) /* last frame */
1344                                 return TXRX_DROP;
1345                         dev_kfree_skb(frame);
1346                         continue;
1347                 }
1348
1349                 ieee80211_deliver_skb(rx);
1350         }
1351
1352         return TXRX_QUEUED;
1353 }
1354
1355 static ieee80211_txrx_result
1356 ieee80211_rx_h_data(struct ieee80211_txrx_data *rx)
1357 {
1358         struct net_device *dev = rx->dev;
1359         u16 fc;
1360         int err;
1361
1362         fc = rx->fc;
1363         if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
1364                 return TXRX_CONTINUE;
1365
1366         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1367                 return TXRX_DROP;
1368
1369         err = ieee80211_data_to_8023(rx);
1370         if (unlikely(err))
1371                 return TXRX_DROP;
1372
1373         if (!ieee80211_frame_allowed(rx))
1374                 return TXRX_DROP;
1375
1376         rx->skb->dev = dev;
1377
1378         dev->stats.rx_packets++;
1379         dev->stats.rx_bytes += rx->skb->len;
1380
1381         ieee80211_deliver_skb(rx);
1382
1383         return TXRX_QUEUED;
1384 }
1385
1386 static ieee80211_txrx_result
1387 ieee80211_rx_h_ctrl(struct ieee80211_txrx_data *rx)
1388 {
1389         struct ieee80211_local *local = rx->local;
1390         struct ieee80211_hw *hw = &local->hw;
1391         struct sk_buff *skb = rx->skb;
1392         struct ieee80211_bar *bar = (struct ieee80211_bar *) skb->data;
1393         struct tid_ampdu_rx *tid_agg_rx;
1394         u16 start_seq_num;
1395         u16 tid;
1396
1397         if (likely((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL))
1398                 return TXRX_CONTINUE;
1399
1400         if ((rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_BACK_REQ) {
1401                 if (!rx->sta)
1402                         return TXRX_CONTINUE;
1403                 tid = le16_to_cpu(bar->control) >> 12;
1404                 tid_agg_rx = &(rx->sta->ampdu_mlme.tid_rx[tid]);
1405                 if (tid_agg_rx->state != HT_AGG_STATE_OPERATIONAL)
1406                         return TXRX_CONTINUE;
1407
1408                 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1409
1410                 /* reset session timer */
1411                 if (tid_agg_rx->timeout) {
1412                         unsigned long expires =
1413                                 jiffies + (tid_agg_rx->timeout / 1000) * HZ;
1414                         mod_timer(&tid_agg_rx->session_timer, expires);
1415                 }
1416
1417                 /* manage reordering buffer according to requested */
1418                 /* sequence number */
1419                 rcu_read_lock();
1420                 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL,
1421                                                  start_seq_num, 1);
1422                 rcu_read_unlock();
1423                 return TXRX_DROP;
1424         }
1425
1426         return TXRX_CONTINUE;
1427 }
1428
1429 static ieee80211_txrx_result
1430 ieee80211_rx_h_mgmt(struct ieee80211_txrx_data *rx)
1431 {
1432         struct ieee80211_sub_if_data *sdata;
1433
1434         if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))
1435                 return TXRX_DROP;
1436
1437         sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1438         if ((sdata->vif.type == IEEE80211_IF_TYPE_STA ||
1439              sdata->vif.type == IEEE80211_IF_TYPE_IBSS) &&
1440             !(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME))
1441                 ieee80211_sta_rx_mgmt(rx->dev, rx->skb, rx->u.rx.status);
1442         else
1443                 return TXRX_DROP;
1444
1445         return TXRX_QUEUED;
1446 }
1447
1448 static inline ieee80211_txrx_result __ieee80211_invoke_rx_handlers(
1449                                 struct ieee80211_local *local,
1450                                 ieee80211_rx_handler *handlers,
1451                                 struct ieee80211_txrx_data *rx,
1452                                 struct sta_info *sta)
1453 {
1454         ieee80211_rx_handler *handler;
1455         ieee80211_txrx_result res = TXRX_DROP;
1456
1457         for (handler = handlers; *handler != NULL; handler++) {
1458                 res = (*handler)(rx);
1459
1460                 switch (res) {
1461                 case TXRX_CONTINUE:
1462                         continue;
1463                 case TXRX_DROP:
1464                         I802_DEBUG_INC(local->rx_handlers_drop);
1465                         if (sta)
1466                                 sta->rx_dropped++;
1467                         break;
1468                 case TXRX_QUEUED:
1469                         I802_DEBUG_INC(local->rx_handlers_queued);
1470                         break;
1471                 }
1472                 break;
1473         }
1474
1475         if (res == TXRX_DROP)
1476                 dev_kfree_skb(rx->skb);
1477         return res;
1478 }
1479
1480 static inline void ieee80211_invoke_rx_handlers(struct ieee80211_local *local,
1481                                                 ieee80211_rx_handler *handlers,
1482                                                 struct ieee80211_txrx_data *rx,
1483                                                 struct sta_info *sta)
1484 {
1485         if (__ieee80211_invoke_rx_handlers(local, handlers, rx, sta) ==
1486             TXRX_CONTINUE)
1487                 dev_kfree_skb(rx->skb);
1488 }
1489
1490 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1491                                             struct ieee80211_hdr *hdr,
1492                                             struct sta_info *sta,
1493                                             struct ieee80211_txrx_data *rx)
1494 {
1495         int keyidx, hdrlen;
1496         DECLARE_MAC_BUF(mac);
1497         DECLARE_MAC_BUF(mac2);
1498
1499         hdrlen = ieee80211_get_hdrlen_from_skb(rx->skb);
1500         if (rx->skb->len >= hdrlen + 4)
1501                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1502         else
1503                 keyidx = -1;
1504
1505         if (net_ratelimit())
1506                 printk(KERN_DEBUG "%s: TKIP hwaccel reported Michael MIC "
1507                        "failure from %s to %s keyidx=%d\n",
1508                        dev->name, print_mac(mac, hdr->addr2),
1509                        print_mac(mac2, hdr->addr1), keyidx);
1510
1511         if (!sta) {
1512                 /*
1513                  * Some hardware seem to generate incorrect Michael MIC
1514                  * reports; ignore them to avoid triggering countermeasures.
1515                  */
1516                 if (net_ratelimit())
1517                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1518                                "error for unknown address %s\n",
1519                                dev->name, print_mac(mac, hdr->addr2));
1520                 goto ignore;
1521         }
1522
1523         if (!(rx->fc & IEEE80211_FCTL_PROTECTED)) {
1524                 if (net_ratelimit())
1525                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1526                                "error for a frame with no PROTECTED flag (src "
1527                                "%s)\n", dev->name, print_mac(mac, hdr->addr2));
1528                 goto ignore;
1529         }
1530
1531         if (rx->sdata->vif.type == IEEE80211_IF_TYPE_AP && keyidx) {
1532                 /*
1533                  * APs with pairwise keys should never receive Michael MIC
1534                  * errors for non-zero keyidx because these are reserved for
1535                  * group keys and only the AP is sending real multicast
1536                  * frames in the BSS.
1537                  */
1538                 if (net_ratelimit())
1539                         printk(KERN_DEBUG "%s: ignored Michael MIC error for "
1540                                "a frame with non-zero keyidx (%d)"
1541                                " (src %s)\n", dev->name, keyidx,
1542                                print_mac(mac, hdr->addr2));
1543                 goto ignore;
1544         }
1545
1546         if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
1547             ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
1548              (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)) {
1549                 if (net_ratelimit())
1550                         printk(KERN_DEBUG "%s: ignored spurious Michael MIC "
1551                                "error for a frame that cannot be encrypted "
1552                                "(fc=0x%04x) (src %s)\n",
1553                                dev->name, rx->fc, print_mac(mac, hdr->addr2));
1554                 goto ignore;
1555         }
1556
1557         mac80211_ev_michael_mic_failure(rx->dev, keyidx, hdr);
1558  ignore:
1559         dev_kfree_skb(rx->skb);
1560         rx->skb = NULL;
1561 }
1562
1563 ieee80211_rx_handler ieee80211_rx_handlers[] =
1564 {
1565         ieee80211_rx_h_if_stats,
1566         ieee80211_rx_h_passive_scan,
1567         ieee80211_rx_h_check,
1568         ieee80211_rx_h_decrypt,
1569         ieee80211_rx_h_sta_process,
1570         ieee80211_rx_h_defragment,
1571         ieee80211_rx_h_ps_poll,
1572         ieee80211_rx_h_michael_mic_verify,
1573         /* this must be after decryption - so header is counted in MPDU mic
1574          * must be before pae and data, so QOS_DATA format frames
1575          * are not passed to user space by these functions
1576          */
1577         ieee80211_rx_h_remove_qos_control,
1578         ieee80211_rx_h_amsdu,
1579         ieee80211_rx_h_data,
1580         ieee80211_rx_h_ctrl,
1581         ieee80211_rx_h_mgmt,
1582         NULL
1583 };
1584
1585 /* main receive path */
1586
1587 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
1588                                 u8 *bssid, struct ieee80211_txrx_data *rx,
1589                                 struct ieee80211_hdr *hdr)
1590 {
1591         int multicast = is_multicast_ether_addr(hdr->addr1);
1592
1593         switch (sdata->vif.type) {
1594         case IEEE80211_IF_TYPE_STA:
1595                 if (!bssid)
1596                         return 0;
1597                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1598                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1599                                 return 0;
1600                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1601                 } else if (!multicast &&
1602                            compare_ether_addr(sdata->dev->dev_addr,
1603                                               hdr->addr1) != 0) {
1604                         if (!(sdata->dev->flags & IFF_PROMISC))
1605                                 return 0;
1606                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1607                 }
1608                 break;
1609         case IEEE80211_IF_TYPE_IBSS:
1610                 if (!bssid)
1611                         return 0;
1612                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1613                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1614                                 return 0;
1615                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1616                 } else if (!multicast &&
1617                            compare_ether_addr(sdata->dev->dev_addr,
1618                                               hdr->addr1) != 0) {
1619                         if (!(sdata->dev->flags & IFF_PROMISC))
1620                                 return 0;
1621                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1622                 } else if (!rx->sta)
1623                         rx->sta = ieee80211_ibss_add_sta(sdata->dev, rx->skb,
1624                                                          bssid, hdr->addr2);
1625                 break;
1626         case IEEE80211_IF_TYPE_VLAN:
1627         case IEEE80211_IF_TYPE_AP:
1628                 if (!bssid) {
1629                         if (compare_ether_addr(sdata->dev->dev_addr,
1630                                                hdr->addr1))
1631                                 return 0;
1632                 } else if (!ieee80211_bssid_match(bssid,
1633                                         sdata->dev->dev_addr)) {
1634                         if (!(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1635                                 return 0;
1636                         rx->flags &= ~IEEE80211_TXRXD_RXRA_MATCH;
1637                 }
1638                 if (sdata->dev == sdata->local->mdev &&
1639                     !(rx->flags & IEEE80211_TXRXD_RXIN_SCAN))
1640                         /* do not receive anything via
1641                          * master device when not scanning */
1642                         return 0;
1643                 break;
1644         case IEEE80211_IF_TYPE_WDS:
1645                 if (bssid ||
1646                     (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
1647                         return 0;
1648                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
1649                         return 0;
1650                 break;
1651         case IEEE80211_IF_TYPE_MNTR:
1652                 /* take everything */
1653                 break;
1654         case IEEE80211_IF_TYPE_INVALID:
1655                 /* should never get here */
1656                 WARN_ON(1);
1657                 break;
1658         }
1659
1660         return 1;
1661 }
1662
1663 /*
1664  * This is the actual Rx frames handler. as it blongs to Rx path it must
1665  * be called with rcu_read_lock protection.
1666  */
1667 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
1668                                          struct sk_buff *skb,
1669                                          struct ieee80211_rx_status *status,
1670                                          u32 load)
1671 {
1672         struct ieee80211_local *local = hw_to_local(hw);
1673         struct ieee80211_sub_if_data *sdata;
1674         struct sta_info *sta;
1675         struct ieee80211_hdr *hdr;
1676         struct ieee80211_txrx_data rx;
1677         u16 type;
1678         int prepares;
1679         struct ieee80211_sub_if_data *prev = NULL;
1680         struct sk_buff *skb_new;
1681         u8 *bssid;
1682         int hdrlen;
1683
1684         hdr = (struct ieee80211_hdr *) skb->data;
1685         memset(&rx, 0, sizeof(rx));
1686         rx.skb = skb;
1687         rx.local = local;
1688
1689         rx.u.rx.status = status;
1690         rx.u.rx.load = load;
1691         rx.fc = le16_to_cpu(hdr->frame_control);
1692         type = rx.fc & IEEE80211_FCTL_FTYPE;
1693
1694         /*
1695          * Drivers are required to align the payload data to a four-byte
1696          * boundary, so the last two bits of the address where it starts
1697          * may not be set. The header is required to be directly before
1698          * the payload data, padding like atheros hardware adds which is
1699          * inbetween the 802.11 header and the payload is not supported,
1700          * the driver is required to move the 802.11 header further back
1701          * in that case.
1702          */
1703         hdrlen = ieee80211_get_hdrlen(rx.fc);
1704         WARN_ON_ONCE(((unsigned long)(skb->data + hdrlen)) & 3);
1705
1706         if (type == IEEE80211_FTYPE_DATA || type == IEEE80211_FTYPE_MGMT)
1707                 local->dot11ReceivedFragmentCount++;
1708
1709         sta = rx.sta = sta_info_get(local, hdr->addr2);
1710         if (sta) {
1711                 rx.dev = rx.sta->dev;
1712                 rx.sdata = IEEE80211_DEV_TO_SUB_IF(rx.dev);
1713         }
1714
1715         if ((status->flag & RX_FLAG_MMIC_ERROR)) {
1716                 ieee80211_rx_michael_mic_report(local->mdev, hdr, sta, &rx);
1717                 goto end;
1718         }
1719
1720         if (unlikely(local->sta_sw_scanning || local->sta_hw_scanning))
1721                 rx.flags |= IEEE80211_TXRXD_RXIN_SCAN;
1722
1723         if (__ieee80211_invoke_rx_handlers(local, local->rx_pre_handlers, &rx,
1724                                            sta) != TXRX_CONTINUE)
1725                 goto end;
1726         skb = rx.skb;
1727
1728         if (sta && !(sta->flags & (WLAN_STA_WDS | WLAN_STA_ASSOC_AP)) &&
1729             !atomic_read(&local->iff_promiscs) &&
1730             !is_multicast_ether_addr(hdr->addr1)) {
1731                 rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
1732                 ieee80211_invoke_rx_handlers(local, local->rx_handlers, &rx,
1733                                              rx.sta);
1734                 sta_info_put(sta);
1735                 return;
1736         }
1737
1738         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1739                 if (!netif_running(sdata->dev))
1740                         continue;
1741
1742                 if (sdata->vif.type == IEEE80211_IF_TYPE_MNTR)
1743                         continue;
1744
1745                 bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
1746                 rx.flags |= IEEE80211_TXRXD_RXRA_MATCH;
1747                 prepares = prepare_for_handlers(sdata, bssid, &rx, hdr);
1748                 /* prepare_for_handlers can change sta */
1749                 sta = rx.sta;
1750
1751                 if (!prepares)
1752                         continue;
1753
1754                 /*
1755                  * frame is destined for this interface, but if it's not
1756                  * also for the previous one we handle that after the
1757                  * loop to avoid copying the SKB once too much
1758                  */
1759
1760                 if (!prev) {
1761                         prev = sdata;
1762                         continue;
1763                 }
1764
1765                 /*
1766                  * frame was destined for the previous interface
1767                  * so invoke RX handlers for it
1768                  */
1769
1770                 skb_new = skb_copy(skb, GFP_ATOMIC);
1771                 if (!skb_new) {
1772                         if (net_ratelimit())
1773                                 printk(KERN_DEBUG "%s: failed to copy "
1774                                        "multicast frame for %s",
1775                                        wiphy_name(local->hw.wiphy),
1776                                        prev->dev->name);
1777                         continue;
1778                 }
1779                 rx.fc = le16_to_cpu(hdr->frame_control);
1780                 rx.skb = skb_new;
1781                 rx.dev = prev->dev;
1782                 rx.sdata = prev;
1783                 ieee80211_invoke_rx_handlers(local, local->rx_handlers,
1784                                              &rx, sta);
1785                 prev = sdata;
1786         }
1787         if (prev) {
1788                 rx.fc = le16_to_cpu(hdr->frame_control);
1789                 rx.skb = skb;
1790                 rx.dev = prev->dev;
1791                 rx.sdata = prev;
1792                 ieee80211_invoke_rx_handlers(local, local->rx_handlers,
1793                                              &rx, sta);
1794         } else
1795                 dev_kfree_skb(skb);
1796
1797  end:
1798         if (sta)
1799                 sta_info_put(sta);
1800 }
1801
1802 #define SEQ_MODULO 0x1000
1803 #define SEQ_MASK   0xfff
1804
1805 static inline int seq_less(u16 sq1, u16 sq2)
1806 {
1807         return (((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1));
1808 }
1809
1810 static inline u16 seq_inc(u16 sq)
1811 {
1812         return ((sq + 1) & SEQ_MASK);
1813 }
1814
1815 static inline u16 seq_sub(u16 sq1, u16 sq2)
1816 {
1817         return ((sq1 - sq2) & SEQ_MASK);
1818 }
1819
1820
1821 /*
1822  * As it function blongs to Rx path it must be called with
1823  * the proper rcu_read_lock protection for its flow.
1824  */
1825 u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
1826                                 struct tid_ampdu_rx *tid_agg_rx,
1827                                 struct sk_buff *skb, u16 mpdu_seq_num,
1828                                 int bar_req)
1829 {
1830         struct ieee80211_local *local = hw_to_local(hw);
1831         struct ieee80211_rx_status status;
1832         u16 head_seq_num, buf_size;
1833         int index;
1834         u32 pkt_load;
1835
1836         buf_size = tid_agg_rx->buf_size;
1837         head_seq_num = tid_agg_rx->head_seq_num;
1838
1839         /* frame with out of date sequence number */
1840         if (seq_less(mpdu_seq_num, head_seq_num)) {
1841                 dev_kfree_skb(skb);
1842                 return 1;
1843         }
1844
1845         /* if frame sequence number exceeds our buffering window size or
1846          * block Ack Request arrived - release stored frames */
1847         if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
1848                 /* new head to the ordering buffer */
1849                 if (bar_req)
1850                         head_seq_num = mpdu_seq_num;
1851                 else
1852                         head_seq_num =
1853                                 seq_inc(seq_sub(mpdu_seq_num, buf_size));
1854                 /* release stored frames up to new head to stack */
1855                 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
1856                         index = seq_sub(tid_agg_rx->head_seq_num,
1857                                 tid_agg_rx->ssn)
1858                                 % tid_agg_rx->buf_size;
1859
1860                         if (tid_agg_rx->reorder_buf[index]) {
1861                                 /* release the reordered frames to stack */
1862                                 memcpy(&status,
1863                                         tid_agg_rx->reorder_buf[index]->cb,
1864                                         sizeof(status));
1865                                 pkt_load = ieee80211_rx_load_stats(local,
1866                                                 tid_agg_rx->reorder_buf[index],
1867                                                 &status);
1868                                 __ieee80211_rx_handle_packet(hw,
1869                                         tid_agg_rx->reorder_buf[index],
1870                                         &status, pkt_load);
1871                                 tid_agg_rx->stored_mpdu_num--;
1872                                 tid_agg_rx->reorder_buf[index] = NULL;
1873                         }
1874                         tid_agg_rx->head_seq_num =
1875                                 seq_inc(tid_agg_rx->head_seq_num);
1876                 }
1877                 if (bar_req)
1878                         return 1;
1879         }
1880
1881         /* now the new frame is always in the range of the reordering */
1882         /* buffer window */
1883         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
1884                                 % tid_agg_rx->buf_size;
1885         /* check if we already stored this frame */
1886         if (tid_agg_rx->reorder_buf[index]) {
1887                 dev_kfree_skb(skb);
1888                 return 1;
1889         }
1890
1891         /* if arrived mpdu is in the right order and nothing else stored */
1892         /* release it immediately */
1893         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
1894                         tid_agg_rx->stored_mpdu_num == 0) {
1895                 tid_agg_rx->head_seq_num =
1896                         seq_inc(tid_agg_rx->head_seq_num);
1897                 return 0;
1898         }
1899
1900         /* put the frame in the reordering buffer */
1901         tid_agg_rx->reorder_buf[index] = skb;
1902         tid_agg_rx->stored_mpdu_num++;
1903         /* release the buffer until next missing frame */
1904         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
1905                                                 % tid_agg_rx->buf_size;
1906         while (tid_agg_rx->reorder_buf[index]) {
1907                 /* release the reordered frame back to stack */
1908                 memcpy(&status, tid_agg_rx->reorder_buf[index]->cb,
1909                         sizeof(status));
1910                 pkt_load = ieee80211_rx_load_stats(local,
1911                                         tid_agg_rx->reorder_buf[index],
1912                                         &status);
1913                 __ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index],
1914                                                 &status, pkt_load);
1915                 tid_agg_rx->stored_mpdu_num--;
1916                 tid_agg_rx->reorder_buf[index] = NULL;
1917                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
1918                 index = seq_sub(tid_agg_rx->head_seq_num,
1919                         tid_agg_rx->ssn) % tid_agg_rx->buf_size;
1920         }
1921         return 1;
1922 }
1923
1924 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
1925                                      struct sk_buff *skb)
1926 {
1927         struct ieee80211_hw *hw = &local->hw;
1928         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1929         struct sta_info *sta;
1930         struct tid_ampdu_rx *tid_agg_rx;
1931         u16 fc, sc;
1932         u16 mpdu_seq_num;
1933         u8 ret = 0, *qc;
1934         int tid;
1935
1936         sta = sta_info_get(local, hdr->addr2);
1937         if (!sta)
1938                 return ret;
1939
1940         fc = le16_to_cpu(hdr->frame_control);
1941
1942         /* filter the QoS data rx stream according to
1943          * STA/TID and check if this STA/TID is on aggregation */
1944         if (!WLAN_FC_IS_QOS_DATA(fc))
1945                 goto end_reorder;
1946
1947         qc = skb->data + ieee80211_get_hdrlen(fc) - QOS_CONTROL_LEN;
1948         tid = qc[0] & QOS_CONTROL_TID_MASK;
1949         tid_agg_rx = &(sta->ampdu_mlme.tid_rx[tid]);
1950
1951         if (tid_agg_rx->state != HT_AGG_STATE_OPERATIONAL)
1952                 goto end_reorder;
1953
1954         /* null data frames are excluded */
1955         if (unlikely(fc & IEEE80211_STYPE_QOS_NULLFUNC))
1956                 goto end_reorder;
1957
1958         /* new un-ordered ampdu frame - process it */
1959
1960         /* reset session timer */
1961         if (tid_agg_rx->timeout) {
1962                 unsigned long expires =
1963                         jiffies + (tid_agg_rx->timeout / 1000) * HZ;
1964                 mod_timer(&tid_agg_rx->session_timer, expires);
1965         }
1966
1967         /* if this mpdu is fragmented - terminate rx aggregation session */
1968         sc = le16_to_cpu(hdr->seq_ctrl);
1969         if (sc & IEEE80211_SCTL_FRAG) {
1970                 ieee80211_sta_stop_rx_ba_session(sta->dev, sta->addr,
1971                         tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
1972                 ret = 1;
1973                 goto end_reorder;
1974         }
1975
1976         /* according to mpdu sequence number deal with reordering buffer */
1977         mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
1978         ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb,
1979                                                 mpdu_seq_num, 0);
1980 end_reorder:
1981         if (sta)
1982                 sta_info_put(sta);
1983         return ret;
1984 }
1985
1986 /*
1987  * This is the receive path handler. It is called by a low level driver when an
1988  * 802.11 MPDU is received from the hardware.
1989  */
1990 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
1991                     struct ieee80211_rx_status *status)
1992 {
1993         struct ieee80211_local *local = hw_to_local(hw);
1994         u32 pkt_load;
1995
1996         /*
1997          * key references and virtual interfaces are protected using RCU
1998          * and this requires that we are in a read-side RCU section during
1999          * receive processing
2000          */
2001         rcu_read_lock();
2002
2003         /*
2004          * Frames with failed FCS/PLCP checksum are not returned,
2005          * all other frames are returned without radiotap header
2006          * if it was previously present.
2007          * Also, frames with less than 16 bytes are dropped.
2008          */
2009         skb = ieee80211_rx_monitor(local, skb, status);
2010         if (!skb) {
2011                 rcu_read_unlock();
2012                 return;
2013         }
2014
2015         pkt_load = ieee80211_rx_load_stats(local, skb, status);
2016         local->channel_use_raw += pkt_load;
2017
2018         if (!ieee80211_rx_reorder_ampdu(local, skb))
2019                 __ieee80211_rx_handle_packet(hw, skb, status, pkt_load);
2020
2021         rcu_read_unlock();
2022 }
2023 EXPORT_SYMBOL(__ieee80211_rx);
2024
2025 /* This is a version of the rx handler that can be called from hard irq
2026  * context. Post the skb on the queue and schedule the tasklet */
2027 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
2028                           struct ieee80211_rx_status *status)
2029 {
2030         struct ieee80211_local *local = hw_to_local(hw);
2031
2032         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2033
2034         skb->dev = local->mdev;
2035         /* copy status into skb->cb for use by tasklet */
2036         memcpy(skb->cb, status, sizeof(*status));
2037         skb->pkt_type = IEEE80211_RX_MSG;
2038         skb_queue_tail(&local->skb_queue, skb);
2039         tasklet_schedule(&local->tasklet);
2040 }
2041 EXPORT_SYMBOL(ieee80211_rx_irqsafe);