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/jiffies.h>
  13 #include <linux/kernel.h>
  14 #include <linux/skbuff.h>
  15 #include <linux/netdevice.h>
  16 #include <linux/etherdevice.h>
  17 #include <linux/rcupdate.h>
  18 #include <net/mac80211.h>
  19 #include <net/ieee80211_radiotap.h>
  20
  21 #include "ieee80211_i.h"
  22 #include "led.h"
  23 #include "mesh.h"
  24 #include "wep.h"
  25 #include "wpa.h"
  26 #include "tkip.h"
  27 #include "wme.h"
  28
  29 u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
  30                                 struct tid_ampdu_rx *tid_agg_rx,
  31                                 struct sk_buff *skb, u16 mpdu_seq_num,
  32                                 int bar_req);
  33 /*
  34  * monitor mode reception
  35  *
  36  * This function cleans up the SKB, i.e. it removes all the stuff
  37  * only useful for monitoring.
  38  */
  39 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
  40                                            struct sk_buff *skb,
  41                                            int rtap_len)
  42 {
  43         skb_pull(skb, rtap_len);
  44
  45         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
  46                 if (likely(skb->len > FCS_LEN))
  47                         skb_trim(skb, skb->len - FCS_LEN);
  48                 else {
  49                         /* driver bug */
  50                         WARN_ON(1);
  51                         dev_kfree_skb(skb);
  52                         skb = NULL;
  53                 }
  54         }
  55
  56         return skb;
  57 }
  58
  59 static inline int should_drop_frame(struct ieee80211_rx_status *status,
  60                                     struct sk_buff *skb,
  61                                     int present_fcs_len,
  62                                     int radiotap_len)
  63 {
  64         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  65
  66         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
  67                 return 1;
  68         if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len))
  69                 return 1;
  70         if (ieee80211_is_ctl(hdr->frame_control) &&
  71             !ieee80211_is_pspoll(hdr->frame_control) &&
  72             !ieee80211_is_back_req(hdr->frame_control))
  73                 return 1;
  74         return 0;
  75 }
  76
  77 static int
  78 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
  79                           struct ieee80211_rx_status *status)
  80 {
  81         int len;
  82
  83         /* always present fields */
  84         len = sizeof(struct ieee80211_radiotap_header) + 9;
  85
  86         if (status->flag & RX_FLAG_TSFT)
  87                 len += 8;
  88         if (local->hw.flags & IEEE80211_HW_SIGNAL_DB ||
  89             local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
  90                 len += 1;
  91         if (local->hw.flags & IEEE80211_HW_NOISE_DBM)
  92                 len += 1;
  93
  94         if (len & 1) /* padding for RX_FLAGS if necessary */
  95                 len++;
  96
  97         /* make sure radiotap starts at a naturally aligned address */
  98         if (len % 8)
  99                 len = roundup(len, 8);
 100
 101         return len;
 102 }
 103
 104 /**
 105  * ieee80211_add_rx_radiotap_header - add radiotap header
 106  *
 107  * add a radiotap header containing all the fields which the hardware provided.
 108  */
 109 static void
 110 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
 111                                  struct sk_buff *skb,
 112                                  struct ieee80211_rx_status *status,
 113                                  struct ieee80211_rate *rate,
 114                                  int rtap_len)
 115 {
 116         struct ieee80211_radiotap_header *rthdr;
 117         unsigned char *pos;
 118
 119         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
 120         memset(rthdr, 0, rtap_len);
 121
 122         /* radiotap header, set always present flags */
 123         rthdr->it_present =
 124                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 125                             (1 << IEEE80211_RADIOTAP_RATE) |
 126                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
 127                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
 128                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
 129         rthdr->it_len = cpu_to_le16(rtap_len);
 130
 131         pos = (unsigned char *)(rthdr+1);
 132
 133         /* the order of the following fields is important */
 134
 135         /* IEEE80211_RADIOTAP_TSFT */
 136         if (status->flag & RX_FLAG_TSFT) {
 137                 *(__le64 *)pos = cpu_to_le64(status->mactime);
 138                 rthdr->it_present |=
 139                         cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
 140                 pos += 8;
 141         }
 142
 143         /* IEEE80211_RADIOTAP_FLAGS */
 144         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 145                 *pos |= IEEE80211_RADIOTAP_F_FCS;
 146         pos++;
 147
 148         /* IEEE80211_RADIOTAP_RATE */
 149         *pos = rate->bitrate / 5;
 150         pos++;
 151
 152         /* IEEE80211_RADIOTAP_CHANNEL */
 153         *(__le16 *)pos = cpu_to_le16(status->freq);
 154         pos += 2;
 155         if (status->band == IEEE80211_BAND_5GHZ)
 156                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
 157                                              IEEE80211_CHAN_5GHZ);
 158         else
 159                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_DYN |
 160                                              IEEE80211_CHAN_2GHZ);
 161         pos += 2;
 162
 163         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
 164         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
 165                 *pos = status->signal;
 166                 rthdr->it_present |=
 167                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
 168                 pos++;
 169         }
 170
 171         /* IEEE80211_RADIOTAP_DBM_ANTNOISE */
 172         if (local->hw.flags & IEEE80211_HW_NOISE_DBM) {
 173                 *pos = status->noise;
 174                 rthdr->it_present |=
 175                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE);
 176                 pos++;
 177         }
 178
 179         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
 180
 181         /* IEEE80211_RADIOTAP_ANTENNA */
 182         *pos = status->antenna;
 183         pos++;
 184
 185         /* IEEE80211_RADIOTAP_DB_ANTSIGNAL */
 186         if (local->hw.flags & IEEE80211_HW_SIGNAL_DB) {
 187                 *pos = status->signal;
 188                 rthdr->it_present |=
 189                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL);
 190                 pos++;
 191         }
 192
 193         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
 194
 195         /* IEEE80211_RADIOTAP_RX_FLAGS */
 196         /* ensure 2 byte alignment for the 2 byte field as required */
 197         if ((pos - (unsigned char *)rthdr) & 1)
 198                 pos++;
 199         /* FIXME: when radiotap gets a 'bad PLCP' flag use it here */
 200         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 201                 *(__le16 *)pos |= cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS);
 202         pos += 2;
 203 }
 204
 205 /*
 206  * This function copies a received frame to all monitor interfaces and
 207  * returns a cleaned-up SKB that no longer includes the FCS nor the
 208  * radiotap header the driver might have added.
 209  */
 210 static struct sk_buff *
 211 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
 212                      struct ieee80211_rx_status *status,
 213                      struct ieee80211_rate *rate)
 214 {
 215         struct ieee80211_sub_if_data *sdata;
 216         int needed_headroom = 0;
 217         struct sk_buff *skb, *skb2;
 218         struct net_device *prev_dev = NULL;
 219         int present_fcs_len = 0;
 220         int rtap_len = 0;
 221
 222         /*
 223          * First, we may need to make a copy of the skb because
 224          *  (1) we need to modify it for radiotap (if not present), and
 225          *  (2) the other RX handlers will modify the skb we got.
 226          *
 227          * We don't need to, of course, if we aren't going to return
 228          * the SKB because it has a bad FCS/PLCP checksum.
 229          */
 230         if (status->flag & RX_FLAG_RADIOTAP)
 231                 rtap_len = ieee80211_get_radiotap_len(origskb->data);
 232         else
 233                 /* room for the radiotap header based on driver features */
 234                 needed_headroom = ieee80211_rx_radiotap_len(local, status);
 235
 236         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 237                 present_fcs_len = FCS_LEN;
 238
 239         if (!local->monitors) {
 240                 if (should_drop_frame(status, origskb, present_fcs_len,
 241                                       rtap_len)) {
 242                         dev_kfree_skb(origskb);
 243                         return NULL;
 244                 }
 245
 246                 return remove_monitor_info(local, origskb, rtap_len);
 247         }
 248
 249         if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) {
 250                 /* only need to expand headroom if necessary */
 251                 skb = origskb;
 252                 origskb = NULL;
 253
 254                 /*
 255                  * This shouldn't trigger often because most devices have an
 256                  * RX header they pull before we get here, and that should
 257                  * be big enough for our radiotap information. We should
 258                  * probably export the length to drivers so that we can have
 259                  * them allocate enough headroom to start with.
 260                  */
 261                 if (skb_headroom(skb) < needed_headroom &&
 262                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
 263                         dev_kfree_skb(skb);
 264                         return NULL;
 265                 }
 266         } else {
 267                 /*
 268                  * Need to make a copy and possibly remove radiotap header
 269                  * and FCS from the original.
 270                  */
 271                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
 272
 273                 origskb = remove_monitor_info(local, origskb, rtap_len);
 274
 275                 if (!skb)
 276                         return origskb;
 277         }
 278
 279         /* if necessary, prepend radiotap information */
 280         if (!(status->flag & RX_FLAG_RADIOTAP))
 281                 ieee80211_add_rx_radiotap_header(local, skb, status, rate,
 282                                                  needed_headroom);
 283
 284         skb_reset_mac_header(skb);
 285         skb->ip_summed = CHECKSUM_UNNECESSARY;
 286         skb->pkt_type = PACKET_OTHERHOST;
 287         skb->protocol = htons(ETH_P_802_2);
 288
 289         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 290                 if (!netif_running(sdata->dev))
 291                         continue;
 292
 293                 if (sdata->vif.type != IEEE80211_IF_TYPE_MNTR)
 294                         continue;
 295
 296                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
 297                         continue;
 298
 299                 if (prev_dev) {
 300                         skb2 = skb_clone(skb, GFP_ATOMIC);
 301                         if (skb2) {
 302                                 skb2->dev = prev_dev;
 303                                 netif_rx(skb2);
 304                         }
 305                 }
 306
 307                 prev_dev = sdata->dev;
 308                 sdata->dev->stats.rx_packets++;
 309                 sdata->dev->stats.rx_bytes += skb->len;
 310         }
 311
 312         if (prev_dev) {
 313                 skb->dev = prev_dev;
 314                 netif_rx(skb);
 315         } else
 316                 dev_kfree_skb(skb);
 317
 318         return origskb;
 319 }
 320
 321
 322 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
 323 {
 324         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 325         int tid;
 326
 327         /* does the frame have a qos control field? */
 328         if (ieee80211_is_data_qos(hdr->frame_control)) {
 329                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 330                 /* frame has qos control */
 331                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
 332                 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
 333                         rx->flags |= IEEE80211_RX_AMSDU;
 334                 else
 335                         rx->flags &= ~IEEE80211_RX_AMSDU;
 336         } else {
 337                 if (unlikely(ieee80211_is_mgmt(hdr->frame_control))) {
 338                         /* Separate TID for management frames */
 339                         tid = NUM_RX_DATA_QUEUES - 1;
 340                 } else {
 341                         /* no qos control present */
 342                         tid = 0; /* 802.1d - Best Effort */
 343                 }
 344         }
 345
 346         rx->queue = tid;
 347         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 348          * For now, set skb->priority to 0 for other cases. */
 349         rx->skb->priority = (tid > 7) ? 0 : tid;
 350 }
 351
 352 static void ieee80211_verify_ip_alignment(struct ieee80211_rx_data *rx)
 353 {
 354 #ifdef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
 355         int hdrlen;
 356
 357         if (!WLAN_FC_DATA_PRESENT(rx->fc))
 358                 return;
 359
 360         /*
 361          * Drivers are required to align the payload data in a way that
 362          * guarantees that the contained IP header is aligned to a four-
 363          * byte boundary. In the case of regular frames, this simply means
 364          * aligning the payload to a four-byte boundary (because either
 365          * the IP header is directly contained, or IV/RFC1042 headers that
 366          * have a length divisible by four are in front of it.
 367          *
 368          * With A-MSDU frames, however, the payload data address must
 369          * yield two modulo four because there are 14-byte 802.3 headers
 370          * within the A-MSDU frames that push the IP header further back
 371          * to a multiple of four again. Thankfully, the specs were sane
 372          * enough this time around to require padding each A-MSDU subframe
 373          * to a length that is a multiple of four.
 374          *
 375          * Padding like atheros hardware adds which is inbetween the 802.11
 376          * header and the payload is not supported, the driver is required
 377          * to move the 802.11 header further back in that case.
 378          */
 379         hdrlen = ieee80211_get_hdrlen(rx->fc);
 380         if (rx->flags & IEEE80211_RX_AMSDU)
 381                 hdrlen += ETH_HLEN;
 382         WARN_ON_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3);
 383 #endif
 384 }
 385
 386
 387 /* rx handlers */
 388
 389 static ieee80211_rx_result debug_noinline
 390 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
 391 {
 392         struct ieee80211_local *local = rx->local;
 393         struct sk_buff *skb = rx->skb;
 394
 395         if (unlikely(local->sta_hw_scanning))
 396                 return ieee80211_sta_rx_scan(rx->dev, skb, rx->status);
 397
 398         if (unlikely(local->sta_sw_scanning)) {
 399                 /* drop all the other packets during a software scan anyway */
 400                 if (ieee80211_sta_rx_scan(rx->dev, skb, rx->status)
 401                     != RX_QUEUED)
 402                         dev_kfree_skb(skb);
 403                 return RX_QUEUED;
 404         }
 405
 406         if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
 407                 /* scanning finished during invoking of handlers */
 408                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
 409                 return RX_DROP_UNUSABLE;
 410         }
 411
 412         return RX_CONTINUE;
 413 }
 414
 415 static ieee80211_rx_result
 416 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
 417 {
 418         int hdrlen = ieee80211_get_hdrlen(rx->fc);
 419         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 420
 421 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
 422
 423         if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) {
 424                 if (!((rx->fc & IEEE80211_FCTL_FROMDS) &&
 425                       (rx->fc & IEEE80211_FCTL_TODS)))
 426                         return RX_DROP_MONITOR;
 427                 if (memcmp(hdr->addr4, rx->dev->dev_addr, ETH_ALEN) == 0)
 428                         return RX_DROP_MONITOR;
 429         }
 430
 431         /* If there is not an established peer link and this is not a peer link
 432          * establisment frame, beacon or probe, drop the frame.
 433          */
 434
 435         if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
 436                 struct ieee80211_mgmt *mgmt;
 437
 438                 if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT)
 439                         return RX_DROP_MONITOR;
 440
 441                 switch (rx->fc & IEEE80211_FCTL_STYPE) {
 442                 case IEEE80211_STYPE_ACTION:
 443                         mgmt = (struct ieee80211_mgmt *)hdr;
 444                         if (mgmt->u.action.category != PLINK_CATEGORY)
 445                                 return RX_DROP_MONITOR;
 446                         /* fall through on else */
 447                 case IEEE80211_STYPE_PROBE_REQ:
 448                 case IEEE80211_STYPE_PROBE_RESP:
 449                 case IEEE80211_STYPE_BEACON:
 450                         return RX_CONTINUE;
 451                         break;
 452                 default:
 453                         return RX_DROP_MONITOR;
 454                 }
 455
 456          } else if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 457                     is_multicast_ether_addr(hdr->addr1) &&
 458                     mesh_rmc_check(hdr->addr4, msh_h_get(hdr, hdrlen), rx->dev))
 459                 return RX_DROP_MONITOR;
 460 #undef msh_h_get
 461
 462         return RX_CONTINUE;
 463 }
 464
 465
 466 static ieee80211_rx_result debug_noinline
 467 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
 468 {
 469         struct ieee80211_hdr *hdr;
 470
 471         hdr = (struct ieee80211_hdr *) rx->skb->data;
 472
 473         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 474         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 475                 if (unlikely(rx->fc & IEEE80211_FCTL_RETRY &&
 476                              rx->sta->last_seq_ctrl[rx->queue] ==
 477                              hdr->seq_ctrl)) {
 478                         if (rx->flags & IEEE80211_RX_RA_MATCH) {
 479                                 rx->local->dot11FrameDuplicateCount++;
 480                                 rx->sta->num_duplicates++;
 481                         }
 482                         return RX_DROP_MONITOR;
 483                 } else
 484                         rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
 485         }
 486
 487         if (unlikely(rx->skb->len < 16)) {
 488                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 489                 return RX_DROP_MONITOR;
 490         }
 491
 492         /* Drop disallowed frame classes based on STA auth/assoc state;
 493          * IEEE 802.11, Chap 5.5.
 494          *
 495          * 80211.o does filtering only based on association state, i.e., it
 496          * drops Class 3 frames from not associated stations. hostapd sends
 497          * deauth/disassoc frames when needed. In addition, hostapd is
 498          * responsible for filtering on both auth and assoc states.
 499          */
 500
 501         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
 502                 return ieee80211_rx_mesh_check(rx);
 503
 504         if (unlikely(((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA ||
 505                       ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_CTL &&
 506                        (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PSPOLL)) &&
 507                      rx->sdata->vif.type != IEEE80211_IF_TYPE_IBSS &&
 508                      (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
 509                 if ((!(rx->fc & IEEE80211_FCTL_FROMDS) &&
 510                      !(rx->fc & IEEE80211_FCTL_TODS) &&
 511                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA)
 512                     || !(rx->flags & IEEE80211_RX_RA_MATCH)) {
 513                         /* Drop IBSS frames and frames for other hosts
 514                          * silently. */
 515                         return RX_DROP_MONITOR;
 516                 }
 517
 518                 return RX_DROP_MONITOR;
 519         }
 520
 521         return RX_CONTINUE;
 522 }
 523
 524
 525 static ieee80211_rx_result debug_noinline
 526 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
 527 {
 528         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 529         int keyidx;
 530         int hdrlen;
 531         ieee80211_rx_result result = RX_DROP_UNUSABLE;
 532         struct ieee80211_key *stakey = NULL;
 533
 534         /*
 535          * Key selection 101
 536          *
 537          * There are three types of keys:
 538          *  - GTK (group keys)
 539          *  - PTK (pairwise keys)
 540          *  - STK (station-to-station pairwise keys)
 541          *
 542          * When selecting a key, we have to distinguish between multicast
 543          * (including broadcast) and unicast frames, the latter can only
 544          * use PTKs and STKs while the former always use GTKs. Unless, of
 545          * course, actual WEP keys ("pre-RSNA") are used, then unicast
 546          * frames can also use key indizes like GTKs. Hence, if we don't
 547          * have a PTK/STK we check the key index for a WEP key.
 548          *
 549          * Note that in a regular BSS, multicast frames are sent by the
 550          * AP only, associated stations unicast the frame to the AP first
 551          * which then multicasts it on their behalf.
 552          *
 553          * There is also a slight problem in IBSS mode: GTKs are negotiated
 554          * with each station, that is something we don't currently handle.
 555          * The spec seems to expect that one negotiates the same key with
 556          * every station but there's no such requirement; VLANs could be
 557          * possible.
 558          */
 559
 560         if (!(rx->fc & IEEE80211_FCTL_PROTECTED))
 561                 return RX_CONTINUE;
 562
 563         /*
 564          * No point in finding a key and decrypting if the frame is neither
 565          * addressed to us nor a multicast frame.
 566          */
 567         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
 568                 return RX_CONTINUE;
 569
 570         if (rx->sta)
 571                 stakey = rcu_dereference(rx->sta->key);
 572
 573         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
 574                 rx->key = stakey;
 575         } else {
 576                 /*
 577                  * The device doesn't give us the IV so we won't be
 578                  * able to look up the key. That's ok though, we
 579                  * don't need to decrypt the frame, we just won't
 580                  * be able to keep statistics accurate.
 581                  * Except for key threshold notifications, should
 582                  * we somehow allow the driver to tell us which key
 583                  * the hardware used if this flag is set?
 584                  */
 585                 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
 586                     (rx->status->flag & RX_FLAG_IV_STRIPPED))
 587                         return RX_CONTINUE;
 588
 589                 hdrlen = ieee80211_get_hdrlen(rx->fc);
 590
 591                 if (rx->skb->len < 8 + hdrlen)
 592                         return RX_DROP_UNUSABLE; /* TODO: count this? */
 593
 594                 /*
 595                  * no need to call ieee80211_wep_get_keyidx,
 596                  * it verifies a bunch of things we've done already
 597                  */
 598                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
 599
 600                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
 601
 602                 /*
 603                  * RSNA-protected unicast frames should always be sent with
 604                  * pairwise or station-to-station keys, but for WEP we allow
 605                  * using a key index as well.
 606                  */
 607                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
 608                     !is_multicast_ether_addr(hdr->addr1))
 609                         rx->key = NULL;
 610         }
 611
 612         if (rx->key) {
 613                 rx->key->tx_rx_count++;
 614                 /* TODO: add threshold stuff again */
 615         } else {
 616                 return RX_DROP_MONITOR;
 617         }
 618
 619         /* Check for weak IVs if possible */
 620         if (rx->sta && rx->key->conf.alg == ALG_WEP &&
 621             ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) &&
 622             (!(rx->status->flag & RX_FLAG_IV_STRIPPED) ||
 623              !(rx->status->flag & RX_FLAG_DECRYPTED)) &&
 624             ieee80211_wep_is_weak_iv(rx->skb, rx->key))
 625                 rx->sta->wep_weak_iv_count++;
 626
 627         switch (rx->key->conf.alg) {
 628         case ALG_WEP:
 629                 result = ieee80211_crypto_wep_decrypt(rx);
 630                 break;
 631         case ALG_TKIP:
 632                 result = ieee80211_crypto_tkip_decrypt(rx);
 633                 break;
 634         case ALG_CCMP:
 635                 result = ieee80211_crypto_ccmp_decrypt(rx);
 636                 break;
 637         }
 638
 639         /* either the frame has been decrypted or will be dropped */
 640         rx->status->flag |= RX_FLAG_DECRYPTED;
 641
 642         return result;
 643 }
 644
 645 static void ap_sta_ps_start(struct net_device *dev, struct sta_info *sta)
 646 {
 647         struct ieee80211_sub_if_data *sdata;
 648         DECLARE_MAC_BUF(mac);
 649
 650         sdata = sta->sdata;
 651
 652         if (sdata->bss)
 653                 atomic_inc(&sdata->bss->num_sta_ps);
 654         set_and_clear_sta_flags(sta, WLAN_STA_PS, WLAN_STA_PSPOLL);
 655 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 656         printk(KERN_DEBUG "%s: STA %s aid %d enters power save mode\n",
 657                dev->name, print_mac(mac, sta->addr), sta->aid);
 658 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 659 }
 660
 661 static int ap_sta_ps_end(struct net_device *dev, struct sta_info *sta)
 662 {
 663         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 664         struct sk_buff *skb;
 665         int sent = 0;
 666         struct ieee80211_sub_if_data *sdata;
 667         struct ieee80211_tx_info *info;
 668         DECLARE_MAC_BUF(mac);
 669
 670         sdata = sta->sdata;
 671
 672         if (sdata->bss)
 673                 atomic_dec(&sdata->bss->num_sta_ps);
 674
 675         clear_sta_flags(sta, WLAN_STA_PS | WLAN_STA_PSPOLL);
 676
 677         if (!skb_queue_empty(&sta->ps_tx_buf))
 678                 sta_info_clear_tim_bit(sta);
 679
 680 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 681         printk(KERN_DEBUG "%s: STA %s aid %d exits power save mode\n",
 682                dev->name, print_mac(mac, sta->addr), sta->aid);
 683 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 684
 685         /* Send all buffered frames to the station */
 686         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
 687                 info = IEEE80211_SKB_CB(skb);
 688                 sent++;
 689                 info->flags |= IEEE80211_TX_CTL_REQUEUE;
 690                 dev_queue_xmit(skb);
 691         }
 692         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
 693                 info = IEEE80211_SKB_CB(skb);
 694                 local->total_ps_buffered--;
 695                 sent++;
 696 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 697                 printk(KERN_DEBUG "%s: STA %s aid %d send PS frame "
 698                        "since STA not sleeping anymore\n", dev->name,
 699                        print_mac(mac, sta->addr), sta->aid);
 700 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 701                 info->flags |= IEEE80211_TX_CTL_REQUEUE;
 702                 dev_queue_xmit(skb);
 703         }
 704
 705         return sent;
 706 }
 707
 708 static ieee80211_rx_result debug_noinline
 709 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
 710 {
 711         struct sta_info *sta = rx->sta;
 712         struct net_device *dev = rx->dev;
 713         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 714
 715         if (!sta)
 716                 return RX_CONTINUE;
 717
 718         /* Update last_rx only for IBSS packets which are for the current
 719          * BSSID to avoid keeping the current IBSS network alive in cases where
 720          * other STAs are using different BSSID. */
 721         if (rx->sdata->vif.type == IEEE80211_IF_TYPE_IBSS) {
 722                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
 723                                                 IEEE80211_IF_TYPE_IBSS);
 724                 if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0)
 725                         sta->last_rx = jiffies;
 726         } else
 727         if (!is_multicast_ether_addr(hdr->addr1) ||
 728             rx->sdata->vif.type == IEEE80211_IF_TYPE_STA) {
 729                 /* Update last_rx only for unicast frames in order to prevent
 730                  * the Probe Request frames (the only broadcast frames from a
 731                  * STA in infrastructure mode) from keeping a connection alive.
 732                  * Mesh beacons will update last_rx when if they are found to
 733                  * match the current local configuration when processed.
 734                  */
 735                 sta->last_rx = jiffies;
 736         }
 737
 738         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
 739                 return RX_CONTINUE;
 740
 741         sta->rx_fragments++;
 742         sta->rx_bytes += rx->skb->len;
 743         sta->last_signal = rx->status->signal;
 744         sta->last_qual = rx->status->qual;
 745         sta->last_noise = rx->status->noise;
 746
 747         if (!(rx->fc & IEEE80211_FCTL_MOREFRAGS)) {
 748                 /* Change STA power saving mode only in the end of a frame
 749                  * exchange sequence */
 750                 if (test_sta_flags(sta, WLAN_STA_PS) &&
 751                     !(rx->fc & IEEE80211_FCTL_PM))
 752                         rx->sent_ps_buffered += ap_sta_ps_end(dev, sta);
 753                 else if (!test_sta_flags(sta, WLAN_STA_PS) &&
 754                          (rx->fc & IEEE80211_FCTL_PM))
 755                         ap_sta_ps_start(dev, sta);
 756         }
 757
 758         /* Drop data::nullfunc frames silently, since they are used only to
 759          * control station power saving mode. */
 760         if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
 761             (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_NULLFUNC) {
 762                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
 763                 /* Update counter and free packet here to avoid counting this
 764                  * as a dropped packed. */
 765                 sta->rx_packets++;
 766                 dev_kfree_skb(rx->skb);
 767                 return RX_QUEUED;
 768         }
 769
 770         return RX_CONTINUE;
 771 } /* ieee80211_rx_h_sta_process */
 772
 773 static inline struct ieee80211_fragment_entry *
 774 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
 775                          unsigned int frag, unsigned int seq, int rx_queue,
 776                          struct sk_buff **skb)
 777 {
 778         struct ieee80211_fragment_entry *entry;
 779         int idx;
 780
 781         idx = sdata->fragment_next;
 782         entry = &sdata->fragments[sdata->fragment_next++];
 783         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
 784                 sdata->fragment_next = 0;
 785
 786         if (!skb_queue_empty(&entry->skb_list)) {
 787 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 788                 struct ieee80211_hdr *hdr =
 789                         (struct ieee80211_hdr *) entry->skb_list.next->data;
 790                 DECLARE_MAC_BUF(mac);
 791                 DECLARE_MAC_BUF(mac2);
 792                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
 793                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
 794                        "addr1=%s addr2=%s\n",
 795                        sdata->dev->name, idx,
 796                        jiffies - entry->first_frag_time, entry->seq,
 797                        entry->last_frag, print_mac(mac, hdr->addr1),
 798                        print_mac(mac2, hdr->addr2));
 799 #endif
 800                 __skb_queue_purge(&entry->skb_list);
 801         }
 802
 803         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
 804         *skb = NULL;
 805         entry->first_frag_time = jiffies;
 806         entry->seq = seq;
 807         entry->rx_queue = rx_queue;
 808         entry->last_frag = frag;
 809         entry->ccmp = 0;
 810         entry->extra_len = 0;
 811
 812         return entry;
 813 }
 814
 815 static inline struct ieee80211_fragment_entry *
 816 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
 817                           u16 fc, unsigned int frag, unsigned int seq,
 818                           int rx_queue, struct ieee80211_hdr *hdr)
 819 {
 820         struct ieee80211_fragment_entry *entry;
 821         int i, idx;
 822
 823         idx = sdata->fragment_next;
 824         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
 825                 struct ieee80211_hdr *f_hdr;
 826                 u16 f_fc;
 827
 828                 idx--;
 829                 if (idx < 0)
 830                         idx = IEEE80211_FRAGMENT_MAX - 1;
 831
 832                 entry = &sdata->fragments[idx];
 833                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
 834                     entry->rx_queue != rx_queue ||
 835                     entry->last_frag + 1 != frag)
 836                         continue;
 837
 838                 f_hdr = (struct ieee80211_hdr *) entry->skb_list.next->data;
 839                 f_fc = le16_to_cpu(f_hdr->frame_control);
 840
 841                 if ((fc & IEEE80211_FCTL_FTYPE) != (f_fc & IEEE80211_FCTL_FTYPE) ||
 842                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
 843                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
 844                         continue;
 845
 846                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
 847                         __skb_queue_purge(&entry->skb_list);
 848                         continue;
 849                 }
 850                 return entry;
 851         }
 852
 853         return NULL;
 854 }
 855
 856 static ieee80211_rx_result debug_noinline
 857 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
 858 {
 859         struct ieee80211_hdr *hdr;
 860         u16 sc;
 861         unsigned int frag, seq;
 862         struct ieee80211_fragment_entry *entry;
 863         struct sk_buff *skb;
 864         DECLARE_MAC_BUF(mac);
 865
 866         hdr = (struct ieee80211_hdr *) rx->skb->data;
 867         sc = le16_to_cpu(hdr->seq_ctrl);
 868         frag = sc & IEEE80211_SCTL_FRAG;
 869
 870         if (likely((!(rx->fc & IEEE80211_FCTL_MOREFRAGS) && frag == 0) ||
 871                    (rx->skb)->len < 24 ||
 872                    is_multicast_ether_addr(hdr->addr1))) {
 873                 /* not fragmented */
 874                 goto out;
 875         }
 876         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
 877
 878         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
 879
 880         if (frag == 0) {
 881                 /* This is the first fragment of a new frame. */
 882                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
 883                                                  rx->queue, &(rx->skb));
 884                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
 885                     (rx->fc & IEEE80211_FCTL_PROTECTED)) {
 886                         /* Store CCMP PN so that we can verify that the next
 887                          * fragment has a sequential PN value. */
 888                         entry->ccmp = 1;
 889                         memcpy(entry->last_pn,
 890                                rx->key->u.ccmp.rx_pn[rx->queue],
 891                                CCMP_PN_LEN);
 892                 }
 893                 return RX_QUEUED;
 894         }
 895
 896         /* This is a fragment for a frame that should already be pending in
 897          * fragment cache. Add this fragment to the end of the pending entry.
 898          */
 899         entry = ieee80211_reassemble_find(rx->sdata, rx->fc, frag, seq,
 900                                           rx->queue, hdr);
 901         if (!entry) {
 902                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 903                 return RX_DROP_MONITOR;
 904         }
 905
 906         /* Verify that MPDUs within one MSDU have sequential PN values.
 907          * (IEEE 802.11i, 8.3.3.4.5) */
 908         if (entry->ccmp) {
 909                 int i;
 910                 u8 pn[CCMP_PN_LEN], *rpn;
 911                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
 912                         return RX_DROP_UNUSABLE;
 913                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
 914                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
 915                         pn[i]++;
 916                         if (pn[i])
 917                                 break;
 918                 }
 919                 rpn = rx->key->u.ccmp.rx_pn[rx->queue];
 920                 if (memcmp(pn, rpn, CCMP_PN_LEN))
 921                         return RX_DROP_UNUSABLE;
 922                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
 923         }
 924
 925         skb_pull(rx->skb, ieee80211_get_hdrlen(rx->fc));
 926         __skb_queue_tail(&entry->skb_list, rx->skb);
 927         entry->last_frag = frag;
 928         entry->extra_len += rx->skb->len;
 929         if (rx->fc & IEEE80211_FCTL_MOREFRAGS) {
 930                 rx->skb = NULL;
 931                 return RX_QUEUED;
 932         }
 933
 934         rx->skb = __skb_dequeue(&entry->skb_list);
 935         if (skb_tailroom(rx->skb) < entry->extra_len) {
 936                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
 937                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
 938                                               GFP_ATOMIC))) {
 939                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 940                         __skb_queue_purge(&entry->skb_list);
 941                         return RX_DROP_UNUSABLE;
 942                 }
 943         }
 944         while ((skb = __skb_dequeue(&entry->skb_list))) {
 945                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
 946                 dev_kfree_skb(skb);
 947         }
 948
 949         /* Complete frame has been reassembled - process it now */
 950         rx->flags |= IEEE80211_RX_FRAGMENTED;
 951
 952  out:
 953         if (rx->sta)
 954                 rx->sta->rx_packets++;
 955         if (is_multicast_ether_addr(hdr->addr1))
 956                 rx->local->dot11MulticastReceivedFrameCount++;
 957         else
 958                 ieee80211_led_rx(rx->local);
 959         return RX_CONTINUE;
 960 }
 961
 962 static ieee80211_rx_result debug_noinline
 963 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
 964 {
 965         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
 966         struct sk_buff *skb;
 967         int no_pending_pkts;
 968         DECLARE_MAC_BUF(mac);
 969
 970         if (likely(!rx->sta ||
 971                    (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL ||
 972                    (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_PSPOLL ||
 973                    !(rx->flags & IEEE80211_RX_RA_MATCH)))
 974                 return RX_CONTINUE;
 975
 976         if ((sdata->vif.type != IEEE80211_IF_TYPE_AP) &&
 977             (sdata->vif.type != IEEE80211_IF_TYPE_VLAN))
 978                 return RX_DROP_UNUSABLE;
 979
 980         skb = skb_dequeue(&rx->sta->tx_filtered);
 981         if (!skb) {
 982                 skb = skb_dequeue(&rx->sta->ps_tx_buf);
 983                 if (skb)
 984                         rx->local->total_ps_buffered--;
 985         }
 986         no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
 987                 skb_queue_empty(&rx->sta->ps_tx_buf);
 988
 989         if (skb) {
 990                 struct ieee80211_hdr *hdr =
 991                         (struct ieee80211_hdr *) skb->data;
 992
 993                 /*
 994                  * Tell TX path to send one frame even though the STA may
 995                  * still remain is PS mode after this frame exchange.
 996                  */
 997                 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
 998
 999 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1000                 printk(KERN_DEBUG "STA %s aid %d: PS Poll (entries after %d)\n",
1001                        print_mac(mac, rx->sta->addr), rx->sta->aid,
1002                        skb_queue_len(&rx->sta->ps_tx_buf));
1003 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1004
1005                 /* Use MoreData flag to indicate whether there are more
1006                  * buffered frames for this STA */
1007                 if (no_pending_pkts)
1008                         hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
1009                 else
1010                         hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1011
1012                 dev_queue_xmit(skb);
1013
1014                 if (no_pending_pkts)
1015                         sta_info_clear_tim_bit(rx->sta);
1016 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1017         } else if (!rx->sent_ps_buffered) {
1018                 /*
1019                  * FIXME: This can be the result of a race condition between
1020                  *        us expiring a frame and the station polling for it.
1021                  *        Should we send it a null-func frame indicating we
1022                  *        have nothing buffered for it?
1023                  */
1024                 printk(KERN_DEBUG "%s: STA %s sent PS Poll even "
1025                        "though there are no buffered frames for it\n",
1026                        rx->dev->name, print_mac(mac, rx->sta->addr));
1027 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1028         }
1029
1030         /* Free PS Poll skb here instead of returning RX_DROP that would
1031          * count as an dropped frame. */
1032         dev_kfree_skb(rx->skb);
1033
1034         return RX_QUEUED;
1035 }
1036
1037 static ieee80211_rx_result debug_noinline
1038 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1039 {
1040         u8 *data = rx->skb->data;
1041         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1042
1043         if (!ieee80211_is_data_qos(hdr->frame_control))
1044                 return RX_CONTINUE;
1045
1046         /* remove the qos control field, update frame type and meta-data */
1047         memmove(data + IEEE80211_QOS_CTL_LEN, data,
1048                 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1049         hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1050         /* change frame type to non QOS */
1051         rx->fc &= ~IEEE80211_STYPE_QOS_DATA;
1052         hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1053
1054         return RX_CONTINUE;
1055 }
1056
1057 static int
1058 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1059 {
1060         if (unlikely(!rx->sta ||
1061             !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1062                 return -EACCES;
1063
1064         return 0;
1065 }
1066
1067 static int
1068 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx)
1069 {
1070         /*
1071          * Pass through unencrypted frames if the hardware has
1072          * decrypted them already.
1073          */
1074         if (rx->status->flag & RX_FLAG_DECRYPTED)
1075                 return 0;
1076
1077         /* Drop unencrypted frames if key is set. */
1078         if (unlikely(!(rx->fc & IEEE80211_FCTL_PROTECTED) &&
1079                      (rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
1080                      (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_NULLFUNC &&
1081                      (rx->key || rx->sdata->drop_unencrypted)))
1082                 return -EACCES;
1083
1084         return 0;
1085 }
1086
1087 static int
1088 ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1089 {
1090         struct net_device *dev = rx->dev;
1091         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
1092         u16 fc, hdrlen, ethertype;
1093         u8 *payload;
1094         u8 dst[ETH_ALEN];
1095         u8 src[ETH_ALEN] __aligned(2);
1096         struct sk_buff *skb = rx->skb;
1097         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1098         DECLARE_MAC_BUF(mac);
1099         DECLARE_MAC_BUF(mac2);
1100         DECLARE_MAC_BUF(mac3);
1101         DECLARE_MAC_BUF(mac4);
1102
1103         fc = rx->fc;
1104
1105         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1106                 return -1;
1107
1108         hdrlen = ieee80211_get_hdrlen(fc);
1109
1110         if (ieee80211_vif_is_mesh(&sdata->vif)) {
1111                 int meshhdrlen = ieee80211_get_mesh_hdrlen(
1112                                 (struct ieee80211s_hdr *) (skb->data + hdrlen));
1113                 /* Copy on cb:
1114                  *  - mesh header: to be used for mesh forwarding
1115                  * decision. It will also be used as mesh header template at
1116                  * tx.c:ieee80211_subif_start_xmit() if interface
1117                  * type is mesh and skb->pkt_type == PACKET_OTHERHOST
1118                  *  - ta: to be used if a RERR needs to be sent.
1119                  */
1120                 memcpy(skb->cb, skb->data + hdrlen, meshhdrlen);
1121                 memcpy(MESH_PREQ(skb), hdr->addr2, ETH_ALEN);
1122                 hdrlen += meshhdrlen;
1123         }
1124
1125         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
1126          * header
1127          * IEEE 802.11 address fields:
1128          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
1129          *   0     0   DA    SA    BSSID n/a
1130          *   0     1   DA    BSSID SA    n/a
1131          *   1     0   BSSID SA    DA    n/a
1132          *   1     1   RA    TA    DA    SA
1133          */
1134
1135         switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
1136         case IEEE80211_FCTL_TODS:
1137                 /* BSSID SA DA */
1138                 memcpy(dst, hdr->addr3, ETH_ALEN);
1139                 memcpy(src, hdr->addr2, ETH_ALEN);
1140
1141                 if (unlikely(sdata->vif.type != IEEE80211_IF_TYPE_AP &&
1142                              sdata->vif.type != IEEE80211_IF_TYPE_VLAN))
1143                         return -1;
1144                 break;
1145         case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
1146                 /* RA TA DA SA */
1147                 memcpy(dst, hdr->addr3, ETH_ALEN);
1148                 memcpy(src, hdr->addr4, ETH_ALEN);
1149
1150                  if (unlikely(sdata->vif.type != IEEE80211_IF_TYPE_WDS &&
1151                              sdata->vif.type != IEEE80211_IF_TYPE_MESH_POINT))
1152                         return -1;
1153                 break;
1154         case IEEE80211_FCTL_FROMDS:
1155                 /* DA BSSID SA */
1156                 memcpy(dst, hdr->addr1, ETH_ALEN);
1157                 memcpy(src, hdr->addr3, ETH_ALEN);
1158
1159                 if (sdata->vif.type != IEEE80211_IF_TYPE_STA ||
1160                     (is_multicast_ether_addr(dst) &&
1161                      !compare_ether_addr(src, dev->dev_addr)))
1162                         return -1;
1163                 break;
1164         case 0:
1165                 /* DA SA BSSID */
1166                 memcpy(dst, hdr->addr1, ETH_ALEN);
1167                 memcpy(src, hdr->addr2, ETH_ALEN);
1168
1169                 if (sdata->vif.type != IEEE80211_IF_TYPE_IBSS)
1170                         return -1;
1171                 break;
1172         }
1173
1174         if (unlikely(skb->len - hdrlen < 8))
1175                 return -1;
1176
1177         payload = skb->data + hdrlen;
1178         ethertype = (payload[6] << 8) | payload[7];
1179
1180         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1181                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1182                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1183                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1184                  * replace EtherType */
1185                 skb_pull(skb, hdrlen + 6);
1186                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1187                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1188         } else {
1189                 struct ethhdr *ehdr;
1190                 __be16 len;
1191
1192                 skb_pull(skb, hdrlen);
1193                 len = htons(skb->len);
1194                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1195                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1196                 memcpy(ehdr->h_source, src, ETH_ALEN);
1197                 ehdr->h_proto = len;
1198         }
1199         return 0;
1200 }
1201
1202 /*
1203  * requires that rx->skb is a frame with ethernet header
1204  */
1205 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx)
1206 {
1207         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1208                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1209         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1210
1211         /*
1212          * Allow EAPOL frames to us/the PAE group address regardless
1213          * of whether the frame was encrypted or not.
1214          */
1215         if (ehdr->h_proto == htons(ETH_P_PAE) &&
1216             (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
1217              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1218                 return true;
1219
1220         if (ieee80211_802_1x_port_control(rx) ||
1221             ieee80211_drop_unencrypted(rx))
1222                 return false;
1223
1224         return true;
1225 }
1226
1227 /*
1228  * requires that rx->skb is a frame with ethernet header
1229  */
1230 static void
1231 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1232 {
1233         struct net_device *dev = rx->dev;
1234         struct ieee80211_local *local = rx->local;
1235         struct sk_buff *skb, *xmit_skb;
1236         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1237         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1238         struct sta_info *dsta;
1239
1240         skb = rx->skb;
1241         xmit_skb = NULL;
1242
1243         if (local->bridge_packets && (sdata->vif.type == IEEE80211_IF_TYPE_AP ||
1244                                       sdata->vif.type == IEEE80211_IF_TYPE_VLAN) &&
1245             (rx->flags & IEEE80211_RX_RA_MATCH)) {
1246                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1247                         /*
1248                          * send multicast frames both to higher layers in
1249                          * local net stack and back to the wireless medium
1250                          */
1251                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1252                         if (!xmit_skb && net_ratelimit())
1253                                 printk(KERN_DEBUG "%s: failed to clone "
1254                                        "multicast frame\n", dev->name);
1255                 } else {
1256                         dsta = sta_info_get(local, skb->data);
1257                         if (dsta && dsta->sdata->dev == dev) {
1258                                 /*
1259                                  * The destination station is associated to
1260                                  * this AP (in this VLAN), so send the frame
1261                                  * directly to it and do not pass it to local
1262                                  * net stack.
1263                                  */
1264                                 xmit_skb = skb;
1265                                 skb = NULL;
1266                         }
1267                 }
1268         }
1269
1270         /* Mesh forwarding */
1271         if (ieee80211_vif_is_mesh(&sdata->vif)) {
1272                 u8 *mesh_ttl = &((struct ieee80211s_hdr *)skb->cb)->ttl;
1273                 (*mesh_ttl)--;
1274
1275                 if (is_multicast_ether_addr(skb->data)) {
1276                         if (*mesh_ttl > 0) {
1277                                 xmit_skb = skb_copy(skb, GFP_ATOMIC);
1278                                 if (xmit_skb)
1279                                         xmit_skb->pkt_type = PACKET_OTHERHOST;
1280                                 else if (net_ratelimit())
1281                                         printk(KERN_DEBUG "%s: failed to clone "
1282                                                "multicast frame\n", dev->name);
1283                         } else
1284                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.sta,
1285                                                              dropped_frames_ttl);
1286                 } else if (skb->pkt_type != PACKET_OTHERHOST &&
1287                         compare_ether_addr(dev->dev_addr, skb->data) != 0) {
1288                         if (*mesh_ttl == 0) {
1289                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.sta,
1290                                                              dropped_frames_ttl);
1291                                 dev_kfree_skb(skb);
1292                                 skb = NULL;
1293                         } else {
1294                                 xmit_skb = skb;
1295                                 xmit_skb->pkt_type = PACKET_OTHERHOST;
1296                                 if (!(dev->flags & IFF_PROMISC))
1297                                         skb  = NULL;
1298                         }
1299                 }
1300         }
1301
1302         if (skb) {
1303                 /* deliver to local stack */
1304                 skb->protocol = eth_type_trans(skb, dev);
1305                 memset(skb->cb, 0, sizeof(skb->cb));
1306                 netif_rx(skb);
1307         }
1308
1309         if (xmit_skb) {
1310                 /* send to wireless media */
1311                 xmit_skb->protocol = htons(ETH_P_802_3);
1312                 skb_reset_network_header(xmit_skb);
1313                 skb_reset_mac_header(xmit_skb);
1314                 dev_queue_xmit(xmit_skb);
1315         }
1316 }
1317
1318 static ieee80211_rx_result debug_noinline
1319 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1320 {
1321         struct net_device *dev = rx->dev;
1322         struct ieee80211_local *local = rx->local;
1323         u16 fc, ethertype;
1324         u8 *payload;
1325         struct sk_buff *skb = rx->skb, *frame = NULL;
1326         const struct ethhdr *eth;
1327         int remaining, err;
1328         u8 dst[ETH_ALEN];
1329         u8 src[ETH_ALEN];
1330         DECLARE_MAC_BUF(mac);
1331
1332         fc = rx->fc;
1333         if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
1334                 return RX_CONTINUE;
1335
1336         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1337                 return RX_DROP_MONITOR;
1338
1339         if (!(rx->flags & IEEE80211_RX_AMSDU))
1340                 return RX_CONTINUE;
1341
1342         err = ieee80211_data_to_8023(rx);
1343         if (unlikely(err))
1344                 return RX_DROP_UNUSABLE;
1345
1346         skb->dev = dev;
1347
1348         dev->stats.rx_packets++;
1349         dev->stats.rx_bytes += skb->len;
1350
1351         /* skip the wrapping header */
1352         eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
1353         if (!eth)
1354                 return RX_DROP_UNUSABLE;
1355
1356         while (skb != frame) {
1357                 u8 padding;
1358                 __be16 len = eth->h_proto;
1359                 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
1360
1361                 remaining = skb->len;
1362                 memcpy(dst, eth->h_dest, ETH_ALEN);
1363                 memcpy(src, eth->h_source, ETH_ALEN);
1364
1365                 padding = ((4 - subframe_len) & 0x3);
1366                 /* the last MSDU has no padding */
1367                 if (subframe_len > remaining)
1368                         return RX_DROP_UNUSABLE;
1369
1370                 skb_pull(skb, sizeof(struct ethhdr));
1371                 /* if last subframe reuse skb */
1372                 if (remaining <= subframe_len + padding)
1373                         frame = skb;
1374                 else {
1375                         frame = dev_alloc_skb(local->hw.extra_tx_headroom +
1376                                               subframe_len);
1377
1378                         if (frame == NULL)
1379                                 return RX_DROP_UNUSABLE;
1380
1381                         skb_reserve(frame, local->hw.extra_tx_headroom +
1382                                     sizeof(struct ethhdr));
1383                         memcpy(skb_put(frame, ntohs(len)), skb->data,
1384                                 ntohs(len));
1385
1386                         eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
1387                                                         padding);
1388                         if (!eth) {
1389                                 dev_kfree_skb(frame);
1390                                 return RX_DROP_UNUSABLE;
1391                         }
1392                 }
1393
1394                 skb_reset_network_header(frame);
1395                 frame->dev = dev;
1396                 frame->priority = skb->priority;
1397                 rx->skb = frame;
1398
1399                 payload = frame->data;
1400                 ethertype = (payload[6] << 8) | payload[7];
1401
1402                 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1403                             ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1404                            compare_ether_addr(payload,
1405                                               bridge_tunnel_header) == 0)) {
1406                         /* remove RFC1042 or Bridge-Tunnel
1407                          * encapsulation and replace EtherType */
1408                         skb_pull(frame, 6);
1409                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1410                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1411                 } else {
1412                         memcpy(skb_push(frame, sizeof(__be16)),
1413                                &len, sizeof(__be16));
1414                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1415                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1416                 }
1417
1418                 if (!ieee80211_frame_allowed(rx)) {
1419                         if (skb == frame) /* last frame */
1420                                 return RX_DROP_UNUSABLE;
1421                         dev_kfree_skb(frame);
1422                         continue;
1423                 }
1424
1425                 ieee80211_deliver_skb(rx);
1426         }
1427
1428         return RX_QUEUED;
1429 }
1430
1431 static ieee80211_rx_result debug_noinline
1432 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1433 {
1434         struct net_device *dev = rx->dev;
1435         u16 fc;
1436         int err;
1437
1438         fc = rx->fc;
1439         if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA))
1440                 return RX_CONTINUE;
1441
1442         if (unlikely(!WLAN_FC_DATA_PRESENT(fc)))
1443                 return RX_DROP_MONITOR;
1444
1445         err = ieee80211_data_to_8023(rx);
1446         if (unlikely(err))
1447                 return RX_DROP_UNUSABLE;
1448
1449         if (!ieee80211_frame_allowed(rx))
1450                 return RX_DROP_MONITOR;
1451
1452         rx->skb->dev = dev;
1453
1454         dev->stats.rx_packets++;
1455         dev->stats.rx_bytes += rx->skb->len;
1456
1457         ieee80211_deliver_skb(rx);
1458
1459         return RX_QUEUED;
1460 }
1461
1462 static ieee80211_rx_result debug_noinline
1463 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
1464 {
1465         struct ieee80211_local *local = rx->local;
1466         struct ieee80211_hw *hw = &local->hw;
1467         struct sk_buff *skb = rx->skb;
1468         struct ieee80211_bar *bar = (struct ieee80211_bar *) skb->data;
1469         struct tid_ampdu_rx *tid_agg_rx;
1470         u16 start_seq_num;
1471         u16 tid;
1472
1473         if (likely((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_CTL))
1474                 return RX_CONTINUE;
1475
1476         if ((rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_BACK_REQ) {
1477                 if (!rx->sta)
1478                         return RX_CONTINUE;
1479                 tid = le16_to_cpu(bar->control) >> 12;
1480                 if (rx->sta->ampdu_mlme.tid_state_rx[tid]
1481                                         != HT_AGG_STATE_OPERATIONAL)
1482                         return RX_CONTINUE;
1483                 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid];
1484
1485                 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1486
1487                 /* reset session timer */
1488                 if (tid_agg_rx->timeout) {
1489                         unsigned long expires =
1490                                 jiffies + (tid_agg_rx->timeout / 1000) * HZ;
1491                         mod_timer(&tid_agg_rx->session_timer, expires);
1492                 }
1493
1494                 /* manage reordering buffer according to requested */
1495                 /* sequence number */
1496                 rcu_read_lock();
1497                 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL,
1498                                                  start_seq_num, 1);
1499                 rcu_read_unlock();
1500                 return RX_DROP_UNUSABLE;
1501         }
1502
1503         return RX_CONTINUE;
1504 }
1505
1506 static ieee80211_rx_result debug_noinline
1507 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
1508 {
1509         struct ieee80211_sub_if_data *sdata;
1510
1511         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1512                 return RX_DROP_MONITOR;
1513
1514         sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1515         if ((sdata->vif.type == IEEE80211_IF_TYPE_STA ||
1516              sdata->vif.type == IEEE80211_IF_TYPE_IBSS ||
1517              sdata->vif.type == IEEE80211_IF_TYPE_MESH_POINT) &&
1518             !(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME))
1519                 ieee80211_sta_rx_mgmt(rx->dev, rx->skb, rx->status);
1520         else
1521                 return RX_DROP_MONITOR;
1522
1523         return RX_QUEUED;
1524 }
1525
1526 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1527                                             struct ieee80211_hdr *hdr,
1528                                             struct ieee80211_rx_data *rx)
1529 {
1530         int keyidx, hdrlen;
1531         DECLARE_MAC_BUF(mac);
1532         DECLARE_MAC_BUF(mac2);
1533
1534         hdrlen = ieee80211_get_hdrlen_from_skb(rx->skb);
1535         if (rx->skb->len >= hdrlen + 4)
1536                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1537         else
1538                 keyidx = -1;
1539
1540         if (!rx->sta) {
1541                 /*
1542                  * Some hardware seem to generate incorrect Michael MIC
1543                  * reports; ignore them to avoid triggering countermeasures.
1544                  */
1545                 goto ignore;
1546         }
1547
1548         if (!(rx->fc & IEEE80211_FCTL_PROTECTED))
1549                 goto ignore;
1550
1551         if (rx->sdata->vif.type == IEEE80211_IF_TYPE_AP && keyidx) {
1552                 /*
1553                  * APs with pairwise keys should never receive Michael MIC
1554                  * errors for non-zero keyidx because these are reserved for
1555                  * group keys and only the AP is sending real multicast
1556                  * frames in the BSS.
1557                  */
1558                 goto ignore;
1559         }
1560
1561         if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
1562             ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
1563              (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH))
1564                 goto ignore;
1565
1566         mac80211_ev_michael_mic_failure(rx->dev, keyidx, hdr);
1567  ignore:
1568         dev_kfree_skb(rx->skb);
1569         rx->skb = NULL;
1570 }
1571
1572 /* TODO: use IEEE80211_RX_FRAGMENTED */
1573 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx)
1574 {
1575         struct ieee80211_sub_if_data *sdata;
1576         struct ieee80211_local *local = rx->local;
1577         struct ieee80211_rtap_hdr {
1578                 struct ieee80211_radiotap_header hdr;
1579                 u8 flags;
1580                 u8 rate;
1581                 __le16 chan_freq;
1582                 __le16 chan_flags;
1583         } __attribute__ ((packed)) *rthdr;
1584         struct sk_buff *skb = rx->skb, *skb2;
1585         struct net_device *prev_dev = NULL;
1586         struct ieee80211_rx_status *status = rx->status;
1587
1588         if (rx->flags & IEEE80211_RX_CMNTR_REPORTED)
1589                 goto out_free_skb;
1590
1591         if (skb_headroom(skb) < sizeof(*rthdr) &&
1592             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
1593                 goto out_free_skb;
1594
1595         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
1596         memset(rthdr, 0, sizeof(*rthdr));
1597         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
1598         rthdr->hdr.it_present =
1599                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
1600                             (1 << IEEE80211_RADIOTAP_RATE) |
1601                             (1 << IEEE80211_RADIOTAP_CHANNEL));
1602
1603         rthdr->rate = rx->rate->bitrate / 5;
1604         rthdr->chan_freq = cpu_to_le16(status->freq);
1605
1606         if (status->band == IEEE80211_BAND_5GHZ)
1607                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
1608                                                 IEEE80211_CHAN_5GHZ);
1609         else
1610                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
1611                                                 IEEE80211_CHAN_2GHZ);
1612
1613         skb_set_mac_header(skb, 0);
1614         skb->ip_summed = CHECKSUM_UNNECESSARY;
1615         skb->pkt_type = PACKET_OTHERHOST;
1616         skb->protocol = htons(ETH_P_802_2);
1617
1618         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1619                 if (!netif_running(sdata->dev))
1620                         continue;
1621
1622                 if (sdata->vif.type != IEEE80211_IF_TYPE_MNTR ||
1623                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
1624                         continue;
1625
1626                 if (prev_dev) {
1627                         skb2 = skb_clone(skb, GFP_ATOMIC);
1628                         if (skb2) {
1629                                 skb2->dev = prev_dev;
1630                                 netif_rx(skb2);
1631                         }
1632                 }
1633
1634                 prev_dev = sdata->dev;
1635                 sdata->dev->stats.rx_packets++;
1636                 sdata->dev->stats.rx_bytes += skb->len;
1637         }
1638
1639         if (prev_dev) {
1640                 skb->dev = prev_dev;
1641                 netif_rx(skb);
1642                 skb = NULL;
1643         } else
1644                 goto out_free_skb;
1645
1646         rx->flags |= IEEE80211_RX_CMNTR_REPORTED;
1647         return;
1648
1649  out_free_skb:
1650         dev_kfree_skb(skb);
1651 }
1652
1653
1654 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
1655                                          struct ieee80211_rx_data *rx,
1656                                          struct sk_buff *skb)
1657 {
1658         ieee80211_rx_result res = RX_DROP_MONITOR;
1659
1660         rx->skb = skb;
1661         rx->sdata = sdata;
1662         rx->dev = sdata->dev;
1663
1664 #define CALL_RXH(rxh)           \
1665         res = rxh(rx);          \
1666         if (res != RX_CONTINUE) \
1667                 goto rxh_done;
1668
1669         CALL_RXH(ieee80211_rx_h_passive_scan)
1670         CALL_RXH(ieee80211_rx_h_check)
1671         CALL_RXH(ieee80211_rx_h_decrypt)
1672         CALL_RXH(ieee80211_rx_h_sta_process)
1673         CALL_RXH(ieee80211_rx_h_defragment)
1674         CALL_RXH(ieee80211_rx_h_ps_poll)
1675         CALL_RXH(ieee80211_rx_h_michael_mic_verify)
1676         /* must be after MMIC verify so header is counted in MPDU mic */
1677         CALL_RXH(ieee80211_rx_h_remove_qos_control)
1678         CALL_RXH(ieee80211_rx_h_amsdu)
1679         CALL_RXH(ieee80211_rx_h_data)
1680         CALL_RXH(ieee80211_rx_h_ctrl)
1681         CALL_RXH(ieee80211_rx_h_mgmt)
1682
1683 #undef CALL_RXH
1684
1685  rxh_done:
1686         switch (res) {
1687         case RX_DROP_MONITOR:
1688                 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
1689                 if (rx->sta)
1690                         rx->sta->rx_dropped++;
1691                 /* fall through */
1692         case RX_CONTINUE:
1693                 ieee80211_rx_cooked_monitor(rx);
1694                 break;
1695         case RX_DROP_UNUSABLE:
1696                 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
1697                 if (rx->sta)
1698                         rx->sta->rx_dropped++;
1699                 dev_kfree_skb(rx->skb);
1700                 break;
1701         case RX_QUEUED:
1702                 I802_DEBUG_INC(sdata->local->rx_handlers_queued);
1703                 break;
1704         }
1705 }
1706
1707 /* main receive path */
1708
1709 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
1710                                 u8 *bssid, struct ieee80211_rx_data *rx,
1711                                 struct ieee80211_hdr *hdr)
1712 {
1713         int multicast = is_multicast_ether_addr(hdr->addr1);
1714
1715         switch (sdata->vif.type) {
1716         case IEEE80211_IF_TYPE_STA:
1717                 if (!bssid)
1718                         return 0;
1719                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1720                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
1721                                 return 0;
1722                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1723                 } else if (!multicast &&
1724                            compare_ether_addr(sdata->dev->dev_addr,
1725                                               hdr->addr1) != 0) {
1726                         if (!(sdata->dev->flags & IFF_PROMISC))
1727                                 return 0;
1728                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1729                 }
1730                 break;
1731         case IEEE80211_IF_TYPE_IBSS:
1732                 if (!bssid)
1733                         return 0;
1734                 if ((rx->fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_MGMT &&
1735                     (rx->fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_BEACON) {
1736                         if (!rx->sta)
1737                                 rx->sta = ieee80211_ibss_add_sta(sdata->dev,
1738                                                 rx->skb, bssid, hdr->addr2,
1739                                                 BIT(rx->status->rate_idx));
1740                         return 1;
1741                 }
1742                 else if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1743                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
1744                                 return 0;
1745                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1746                 } else if (!multicast &&
1747                            compare_ether_addr(sdata->dev->dev_addr,
1748                                               hdr->addr1) != 0) {
1749                         if (!(sdata->dev->flags & IFF_PROMISC))
1750                                 return 0;
1751                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1752                 } else if (!rx->sta)
1753                         rx->sta = ieee80211_ibss_add_sta(sdata->dev, rx->skb,
1754                                                 bssid, hdr->addr2,
1755                                                 BIT(rx->status->rate_idx));
1756                 break;
1757         case IEEE80211_IF_TYPE_MESH_POINT:
1758                 if (!multicast &&
1759                     compare_ether_addr(sdata->dev->dev_addr,
1760                                        hdr->addr1) != 0) {
1761                         if (!(sdata->dev->flags & IFF_PROMISC))
1762                                 return 0;
1763
1764                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1765                 }
1766                 break;
1767         case IEEE80211_IF_TYPE_VLAN:
1768         case IEEE80211_IF_TYPE_AP:
1769                 if (!bssid) {
1770                         if (compare_ether_addr(sdata->dev->dev_addr,
1771                                                hdr->addr1))
1772                                 return 0;
1773                 } else if (!ieee80211_bssid_match(bssid,
1774                                         sdata->dev->dev_addr)) {
1775                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
1776                                 return 0;
1777                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1778                 }
1779                 if (sdata->dev == sdata->local->mdev &&
1780                     !(rx->flags & IEEE80211_RX_IN_SCAN))
1781                         /* do not receive anything via
1782                          * master device when not scanning */
1783                         return 0;
1784                 break;
1785         case IEEE80211_IF_TYPE_WDS:
1786                 if (bssid ||
1787                     (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
1788                         return 0;
1789                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
1790                         return 0;
1791                 break;
1792         case IEEE80211_IF_TYPE_MNTR:
1793                 /* take everything */
1794                 break;
1795         case IEEE80211_IF_TYPE_INVALID:
1796                 /* should never get here */
1797                 WARN_ON(1);
1798                 break;
1799         }
1800
1801         return 1;
1802 }
1803
1804 /*
1805  * This is the actual Rx frames handler. as it blongs to Rx path it must
1806  * be called with rcu_read_lock protection.
1807  */
1808 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
1809                                          struct sk_buff *skb,
1810                                          struct ieee80211_rx_status *status,
1811                                          struct ieee80211_rate *rate)
1812 {
1813         struct ieee80211_local *local = hw_to_local(hw);
1814         struct ieee80211_sub_if_data *sdata;
1815         struct ieee80211_hdr *hdr;
1816         struct ieee80211_rx_data rx;
1817         u16 type;
1818         int prepares;
1819         struct ieee80211_sub_if_data *prev = NULL;
1820         struct sk_buff *skb_new;
1821         u8 *bssid;
1822
1823         hdr = (struct ieee80211_hdr *) skb->data;
1824         memset(&rx, 0, sizeof(rx));
1825         rx.skb = skb;
1826         rx.local = local;
1827
1828         rx.status = status;
1829         rx.rate = rate;
1830         rx.fc = le16_to_cpu(hdr->frame_control);
1831         type = rx.fc & IEEE80211_FCTL_FTYPE;
1832
1833         if (type == IEEE80211_FTYPE_DATA || type == IEEE80211_FTYPE_MGMT)
1834                 local->dot11ReceivedFragmentCount++;
1835
1836         rx.sta = sta_info_get(local, hdr->addr2);
1837         if (rx.sta) {
1838                 rx.sdata = rx.sta->sdata;
1839                 rx.dev = rx.sta->sdata->dev;
1840         }
1841
1842         if ((status->flag & RX_FLAG_MMIC_ERROR)) {
1843                 ieee80211_rx_michael_mic_report(local->mdev, hdr, &rx);
1844                 return;
1845         }
1846
1847         if (unlikely(local->sta_sw_scanning || local->sta_hw_scanning))
1848                 rx.flags |= IEEE80211_RX_IN_SCAN;
1849
1850         ieee80211_parse_qos(&rx);
1851         ieee80211_verify_ip_alignment(&rx);
1852
1853         skb = rx.skb;
1854
1855         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1856                 if (!netif_running(sdata->dev))
1857                         continue;
1858
1859                 if (sdata->vif.type == IEEE80211_IF_TYPE_MNTR)
1860                         continue;
1861
1862                 bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
1863                 rx.flags |= IEEE80211_RX_RA_MATCH;
1864                 prepares = prepare_for_handlers(sdata, bssid, &rx, hdr);
1865
1866                 if (!prepares)
1867                         continue;
1868
1869                 /*
1870                  * frame is destined for this interface, but if it's not
1871                  * also for the previous one we handle that after the
1872                  * loop to avoid copying the SKB once too much
1873                  */
1874
1875                 if (!prev) {
1876                         prev = sdata;
1877                         continue;
1878                 }
1879
1880                 /*
1881                  * frame was destined for the previous interface
1882                  * so invoke RX handlers for it
1883                  */
1884
1885                 skb_new = skb_copy(skb, GFP_ATOMIC);
1886                 if (!skb_new) {
1887                         if (net_ratelimit())
1888                                 printk(KERN_DEBUG "%s: failed to copy "
1889                                        "multicast frame for %s\n",
1890                                        wiphy_name(local->hw.wiphy),
1891                                        prev->dev->name);
1892                         continue;
1893                 }
1894                 rx.fc = le16_to_cpu(hdr->frame_control);
1895                 ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
1896                 prev = sdata;
1897         }
1898         if (prev) {
1899                 rx.fc = le16_to_cpu(hdr->frame_control);
1900                 ieee80211_invoke_rx_handlers(prev, &rx, skb);
1901         } else
1902                 dev_kfree_skb(skb);
1903 }
1904
1905 #define SEQ_MODULO 0x1000
1906 #define SEQ_MASK   0xfff
1907
1908 static inline int seq_less(u16 sq1, u16 sq2)
1909 {
1910         return (((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1));
1911 }
1912
1913 static inline u16 seq_inc(u16 sq)
1914 {
1915         return ((sq + 1) & SEQ_MASK);
1916 }
1917
1918 static inline u16 seq_sub(u16 sq1, u16 sq2)
1919 {
1920         return ((sq1 - sq2) & SEQ_MASK);
1921 }
1922
1923
1924 /*
1925  * As it function blongs to Rx path it must be called with
1926  * the proper rcu_read_lock protection for its flow.
1927  */
1928 u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
1929                                 struct tid_ampdu_rx *tid_agg_rx,
1930                                 struct sk_buff *skb, u16 mpdu_seq_num,
1931                                 int bar_req)
1932 {
1933         struct ieee80211_local *local = hw_to_local(hw);
1934         struct ieee80211_rx_status status;
1935         u16 head_seq_num, buf_size;
1936         int index;
1937         struct ieee80211_supported_band *sband;
1938         struct ieee80211_rate *rate;
1939
1940         buf_size = tid_agg_rx->buf_size;
1941         head_seq_num = tid_agg_rx->head_seq_num;
1942
1943         /* frame with out of date sequence number */
1944         if (seq_less(mpdu_seq_num, head_seq_num)) {
1945                 dev_kfree_skb(skb);
1946                 return 1;
1947         }
1948
1949         /* if frame sequence number exceeds our buffering window size or
1950          * block Ack Request arrived - release stored frames */
1951         if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
1952                 /* new head to the ordering buffer */
1953                 if (bar_req)
1954                         head_seq_num = mpdu_seq_num;
1955                 else
1956                         head_seq_num =
1957                                 seq_inc(seq_sub(mpdu_seq_num, buf_size));
1958                 /* release stored frames up to new head to stack */
1959                 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
1960                         index = seq_sub(tid_agg_rx->head_seq_num,
1961                                 tid_agg_rx->ssn)
1962                                 % tid_agg_rx->buf_size;
1963
1964                         if (tid_agg_rx->reorder_buf[index]) {
1965                                 /* release the reordered frames to stack */
1966                                 memcpy(&status,
1967                                         tid_agg_rx->reorder_buf[index]->cb,
1968                                         sizeof(status));
1969                                 sband = local->hw.wiphy->bands[status.band];
1970                                 rate = &sband->bitrates[status.rate_idx];
1971                                 __ieee80211_rx_handle_packet(hw,
1972                                         tid_agg_rx->reorder_buf[index],
1973                                         &status, rate);
1974                                 tid_agg_rx->stored_mpdu_num--;
1975                                 tid_agg_rx->reorder_buf[index] = NULL;
1976                         }
1977                         tid_agg_rx->head_seq_num =
1978                                 seq_inc(tid_agg_rx->head_seq_num);
1979                 }
1980                 if (bar_req)
1981                         return 1;
1982         }
1983
1984         /* now the new frame is always in the range of the reordering */
1985         /* buffer window */
1986         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
1987                                 % tid_agg_rx->buf_size;
1988         /* check if we already stored this frame */
1989         if (tid_agg_rx->reorder_buf[index]) {
1990                 dev_kfree_skb(skb);
1991                 return 1;
1992         }
1993
1994         /* if arrived mpdu is in the right order and nothing else stored */
1995         /* release it immediately */
1996         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
1997                         tid_agg_rx->stored_mpdu_num == 0) {
1998                 tid_agg_rx->head_seq_num =
1999                         seq_inc(tid_agg_rx->head_seq_num);
2000                 return 0;
2001         }
2002
2003         /* put the frame in the reordering buffer */
2004         tid_agg_rx->reorder_buf[index] = skb;
2005         tid_agg_rx->stored_mpdu_num++;
2006         /* release the buffer until next missing frame */
2007         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
2008                                                 % tid_agg_rx->buf_size;
2009         while (tid_agg_rx->reorder_buf[index]) {
2010                 /* release the reordered frame back to stack */
2011                 memcpy(&status, tid_agg_rx->reorder_buf[index]->cb,
2012                         sizeof(status));
2013                 sband = local->hw.wiphy->bands[status.band];
2014                 rate = &sband->bitrates[status.rate_idx];
2015                 __ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index],
2016                                              &status, rate);
2017                 tid_agg_rx->stored_mpdu_num--;
2018                 tid_agg_rx->reorder_buf[index] = NULL;
2019                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
2020                 index = seq_sub(tid_agg_rx->head_seq_num,
2021                         tid_agg_rx->ssn) % tid_agg_rx->buf_size;
2022         }
2023         return 1;
2024 }
2025
2026 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
2027                                      struct sk_buff *skb)
2028 {
2029         struct ieee80211_hw *hw = &local->hw;
2030         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
2031         struct sta_info *sta;
2032         struct tid_ampdu_rx *tid_agg_rx;
2033         u16 sc;
2034         u16 mpdu_seq_num;
2035         u8 ret = 0;
2036         int tid;
2037
2038         sta = sta_info_get(local, hdr->addr2);
2039         if (!sta)
2040                 return ret;
2041
2042         /* filter the QoS data rx stream according to
2043          * STA/TID and check if this STA/TID is on aggregation */
2044         if (!ieee80211_is_data_qos(hdr->frame_control))
2045                 goto end_reorder;
2046
2047         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
2048
2049         if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
2050                 goto end_reorder;
2051
2052         tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
2053
2054         /* null data frames are excluded */
2055         if (unlikely(ieee80211_is_nullfunc(hdr->frame_control)))
2056                 goto end_reorder;
2057
2058         /* new un-ordered ampdu frame - process it */
2059
2060         /* reset session timer */
2061         if (tid_agg_rx->timeout) {
2062                 unsigned long expires =
2063                         jiffies + (tid_agg_rx->timeout / 1000) * HZ;
2064                 mod_timer(&tid_agg_rx->session_timer, expires);
2065         }
2066
2067         /* if this mpdu is fragmented - terminate rx aggregation session */
2068         sc = le16_to_cpu(hdr->seq_ctrl);
2069         if (sc & IEEE80211_SCTL_FRAG) {
2070                 ieee80211_sta_stop_rx_ba_session(sta->sdata->dev, sta->addr,
2071                         tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
2072                 ret = 1;
2073                 goto end_reorder;
2074         }
2075
2076         /* according to mpdu sequence number deal with reordering buffer */
2077         mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
2078         ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb,
2079                                                 mpdu_seq_num, 0);
2080  end_reorder:
2081         return ret;
2082 }
2083
2084 /*
2085  * This is the receive path handler. It is called by a low level driver when an
2086  * 802.11 MPDU is received from the hardware.
2087  */
2088 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
2089                     struct ieee80211_rx_status *status)
2090 {
2091         struct ieee80211_local *local = hw_to_local(hw);
2092         struct ieee80211_rate *rate = NULL;
2093         struct ieee80211_supported_band *sband;
2094
2095         if (status->band < 0 ||
2096             status->band >= IEEE80211_NUM_BANDS) {
2097                 WARN_ON(1);
2098                 return;
2099         }
2100
2101         sband = local->hw.wiphy->bands[status->band];
2102
2103         if (!sband ||
2104             status->rate_idx < 0 ||
2105             status->rate_idx >= sband->n_bitrates) {
2106                 WARN_ON(1);
2107                 return;
2108         }
2109
2110         rate = &sband->bitrates[status->rate_idx];
2111
2112         /*
2113          * key references and virtual interfaces are protected using RCU
2114          * and this requires that we are in a read-side RCU section during
2115          * receive processing
2116          */
2117         rcu_read_lock();
2118
2119         /*
2120          * Frames with failed FCS/PLCP checksum are not returned,
2121          * all other frames are returned without radiotap header
2122          * if it was previously present.
2123          * Also, frames with less than 16 bytes are dropped.
2124          */
2125         skb = ieee80211_rx_monitor(local, skb, status, rate);
2126         if (!skb) {
2127                 rcu_read_unlock();
2128                 return;
2129         }
2130
2131         if (!ieee80211_rx_reorder_ampdu(local, skb))
2132                 __ieee80211_rx_handle_packet(hw, skb, status, rate);
2133
2134         rcu_read_unlock();
2135 }
2136 EXPORT_SYMBOL(__ieee80211_rx);
2137
2138 /* This is a version of the rx handler that can be called from hard irq
2139  * context. Post the skb on the queue and schedule the tasklet */
2140 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
2141                           struct ieee80211_rx_status *status)
2142 {
2143         struct ieee80211_local *local = hw_to_local(hw);
2144
2145         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2146
2147         skb->dev = local->mdev;
2148         /* copy status into skb->cb for use by tasklet */
2149         memcpy(skb->cb, status, sizeof(*status));
2150         skb->pkt_type = IEEE80211_RX_MSG;
2151         skb_queue_tail(&local->skb_queue, skb);
2152         tasklet_schedule(&local->tasklet);
2153 }
2154 EXPORT_SYMBOL(ieee80211_rx_irqsafe);