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         if (status->flag & RX_FLAG_SHORTPRE)
 147                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
 148         pos++;
 149
 150         /* IEEE80211_RADIOTAP_RATE */
 151         *pos = rate->bitrate / 5;
 152         pos++;
 153
 154         /* IEEE80211_RADIOTAP_CHANNEL */
 155         *(__le16 *)pos = cpu_to_le16(status->freq);
 156         pos += 2;
 157         if (status->band == IEEE80211_BAND_5GHZ)
 158                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
 159                                              IEEE80211_CHAN_5GHZ);
 160         else if (rate->flags & IEEE80211_RATE_ERP_G)
 161                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
 162                                              IEEE80211_CHAN_2GHZ);
 163         else
 164                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_CCK |
 165                                              IEEE80211_CHAN_2GHZ);
 166         pos += 2;
 167
 168         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
 169         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
 170                 *pos = status->signal;
 171                 rthdr->it_present |=
 172                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
 173                 pos++;
 174         }
 175
 176         /* IEEE80211_RADIOTAP_DBM_ANTNOISE */
 177         if (local->hw.flags & IEEE80211_HW_NOISE_DBM) {
 178                 *pos = status->noise;
 179                 rthdr->it_present |=
 180                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE);
 181                 pos++;
 182         }
 183
 184         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
 185
 186         /* IEEE80211_RADIOTAP_ANTENNA */
 187         *pos = status->antenna;
 188         pos++;
 189
 190         /* IEEE80211_RADIOTAP_DB_ANTSIGNAL */
 191         if (local->hw.flags & IEEE80211_HW_SIGNAL_DB) {
 192                 *pos = status->signal;
 193                 rthdr->it_present |=
 194                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL);
 195                 pos++;
 196         }
 197
 198         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
 199
 200         /* IEEE80211_RADIOTAP_RX_FLAGS */
 201         /* ensure 2 byte alignment for the 2 byte field as required */
 202         if ((pos - (unsigned char *)rthdr) & 1)
 203                 pos++;
 204         /* FIXME: when radiotap gets a 'bad PLCP' flag use it here */
 205         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 206                 *(__le16 *)pos |= cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS);
 207         pos += 2;
 208 }
 209
 210 /*
 211  * This function copies a received frame to all monitor interfaces and
 212  * returns a cleaned-up SKB that no longer includes the FCS nor the
 213  * radiotap header the driver might have added.
 214  */
 215 static struct sk_buff *
 216 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
 217                      struct ieee80211_rx_status *status,
 218                      struct ieee80211_rate *rate)
 219 {
 220         struct ieee80211_sub_if_data *sdata;
 221         int needed_headroom = 0;
 222         struct sk_buff *skb, *skb2;
 223         struct net_device *prev_dev = NULL;
 224         int present_fcs_len = 0;
 225         int rtap_len = 0;
 226
 227         /*
 228          * First, we may need to make a copy of the skb because
 229          *  (1) we need to modify it for radiotap (if not present), and
 230          *  (2) the other RX handlers will modify the skb we got.
 231          *
 232          * We don't need to, of course, if we aren't going to return
 233          * the SKB because it has a bad FCS/PLCP checksum.
 234          */
 235         if (status->flag & RX_FLAG_RADIOTAP)
 236                 rtap_len = ieee80211_get_radiotap_len(origskb->data);
 237         else
 238                 /* room for the radiotap header based on driver features */
 239                 needed_headroom = ieee80211_rx_radiotap_len(local, status);
 240
 241         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 242                 present_fcs_len = FCS_LEN;
 243
 244         if (!local->monitors) {
 245                 if (should_drop_frame(status, origskb, present_fcs_len,
 246                                       rtap_len)) {
 247                         dev_kfree_skb(origskb);
 248                         return NULL;
 249                 }
 250
 251                 return remove_monitor_info(local, origskb, rtap_len);
 252         }
 253
 254         if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) {
 255                 /* only need to expand headroom if necessary */
 256                 skb = origskb;
 257                 origskb = NULL;
 258
 259                 /*
 260                  * This shouldn't trigger often because most devices have an
 261                  * RX header they pull before we get here, and that should
 262                  * be big enough for our radiotap information. We should
 263                  * probably export the length to drivers so that we can have
 264                  * them allocate enough headroom to start with.
 265                  */
 266                 if (skb_headroom(skb) < needed_headroom &&
 267                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
 268                         dev_kfree_skb(skb);
 269                         return NULL;
 270                 }
 271         } else {
 272                 /*
 273                  * Need to make a copy and possibly remove radiotap header
 274                  * and FCS from the original.
 275                  */
 276                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
 277
 278                 origskb = remove_monitor_info(local, origskb, rtap_len);
 279
 280                 if (!skb)
 281                         return origskb;
 282         }
 283
 284         /* if necessary, prepend radiotap information */
 285         if (!(status->flag & RX_FLAG_RADIOTAP))
 286                 ieee80211_add_rx_radiotap_header(local, skb, status, rate,
 287                                                  needed_headroom);
 288
 289         skb_reset_mac_header(skb);
 290         skb->ip_summed = CHECKSUM_UNNECESSARY;
 291         skb->pkt_type = PACKET_OTHERHOST;
 292         skb->protocol = htons(ETH_P_802_2);
 293
 294         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 295                 if (!netif_running(sdata->dev))
 296                         continue;
 297
 298                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
 299                         continue;
 300
 301                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
 302                         continue;
 303
 304                 if (prev_dev) {
 305                         skb2 = skb_clone(skb, GFP_ATOMIC);
 306                         if (skb2) {
 307                                 skb2->dev = prev_dev;
 308                                 netif_rx(skb2);
 309                         }
 310                 }
 311
 312                 prev_dev = sdata->dev;
 313                 sdata->dev->stats.rx_packets++;
 314                 sdata->dev->stats.rx_bytes += skb->len;
 315         }
 316
 317         if (prev_dev) {
 318                 skb->dev = prev_dev;
 319                 netif_rx(skb);
 320         } else
 321                 dev_kfree_skb(skb);
 322
 323         return origskb;
 324 }
 325
 326
 327 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
 328 {
 329         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 330         int tid;
 331
 332         /* does the frame have a qos control field? */
 333         if (ieee80211_is_data_qos(hdr->frame_control)) {
 334                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 335                 /* frame has qos control */
 336                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
 337                 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
 338                         rx->flags |= IEEE80211_RX_AMSDU;
 339                 else
 340                         rx->flags &= ~IEEE80211_RX_AMSDU;
 341         } else {
 342                 /*
 343                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
 344                  *
 345                  *      Sequence numbers for management frames, QoS data
 346                  *      frames with a broadcast/multicast address in the
 347                  *      Address 1 field, and all non-QoS data frames sent
 348                  *      by QoS STAs are assigned using an additional single
 349                  *      modulo-4096 counter, [...]
 350                  *
 351                  * We also use that counter for non-QoS STAs.
 352                  */
 353                 tid = NUM_RX_DATA_QUEUES - 1;
 354         }
 355
 356         rx->queue = tid;
 357         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 358          * For now, set skb->priority to 0 for other cases. */
 359         rx->skb->priority = (tid > 7) ? 0 : tid;
 360 }
 361
 362 static void ieee80211_verify_ip_alignment(struct ieee80211_rx_data *rx)
 363 {
 364 #ifdef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
 365         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 366         int hdrlen;
 367
 368         if (!ieee80211_is_data_present(hdr->frame_control))
 369                 return;
 370
 371         /*
 372          * Drivers are required to align the payload data in a way that
 373          * guarantees that the contained IP header is aligned to a four-
 374          * byte boundary. In the case of regular frames, this simply means
 375          * aligning the payload to a four-byte boundary (because either
 376          * the IP header is directly contained, or IV/RFC1042 headers that
 377          * have a length divisible by four are in front of it.
 378          *
 379          * With A-MSDU frames, however, the payload data address must
 380          * yield two modulo four because there are 14-byte 802.3 headers
 381          * within the A-MSDU frames that push the IP header further back
 382          * to a multiple of four again. Thankfully, the specs were sane
 383          * enough this time around to require padding each A-MSDU subframe
 384          * to a length that is a multiple of four.
 385          *
 386          * Padding like atheros hardware adds which is inbetween the 802.11
 387          * header and the payload is not supported, the driver is required
 388          * to move the 802.11 header further back in that case.
 389          */
 390         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 391         if (rx->flags & IEEE80211_RX_AMSDU)
 392                 hdrlen += ETH_HLEN;
 393         WARN_ON_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3);
 394 #endif
 395 }
 396
 397
 398 /* rx handlers */
 399
 400 static ieee80211_rx_result debug_noinline
 401 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
 402 {
 403         struct ieee80211_local *local = rx->local;
 404         struct sk_buff *skb = rx->skb;
 405
 406         if (unlikely(local->hw_scanning))
 407                 return ieee80211_scan_rx(rx->sdata, skb, rx->status);
 408
 409         if (unlikely(local->sw_scanning)) {
 410                 /* drop all the other packets during a software scan anyway */
 411                 if (ieee80211_scan_rx(rx->sdata, skb, rx->status)
 412                     != RX_QUEUED)
 413                         dev_kfree_skb(skb);
 414                 return RX_QUEUED;
 415         }
 416
 417         if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
 418                 /* scanning finished during invoking of handlers */
 419                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
 420                 return RX_DROP_UNUSABLE;
 421         }
 422
 423         return RX_CONTINUE;
 424 }
 425
 426 static ieee80211_rx_result
 427 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
 428 {
 429         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 430         unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
 431
 432         if (ieee80211_is_data(hdr->frame_control)) {
 433                 if (!ieee80211_has_a4(hdr->frame_control))
 434                         return RX_DROP_MONITOR;
 435                 if (memcmp(hdr->addr4, rx->dev->dev_addr, ETH_ALEN) == 0)
 436                         return RX_DROP_MONITOR;
 437         }
 438
 439         /* If there is not an established peer link and this is not a peer link
 440          * establisment frame, beacon or probe, drop the frame.
 441          */
 442
 443         if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
 444                 struct ieee80211_mgmt *mgmt;
 445
 446                 if (!ieee80211_is_mgmt(hdr->frame_control))
 447                         return RX_DROP_MONITOR;
 448
 449                 if (ieee80211_is_action(hdr->frame_control)) {
 450                         mgmt = (struct ieee80211_mgmt *)hdr;
 451                         if (mgmt->u.action.category != PLINK_CATEGORY)
 452                                 return RX_DROP_MONITOR;
 453                         return RX_CONTINUE;
 454                 }
 455
 456                 if (ieee80211_is_probe_req(hdr->frame_control) ||
 457                     ieee80211_is_probe_resp(hdr->frame_control) ||
 458                     ieee80211_is_beacon(hdr->frame_control))
 459                         return RX_CONTINUE;
 460
 461                 return RX_DROP_MONITOR;
 462
 463         }
 464
 465 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
 466
 467         if (ieee80211_is_data(hdr->frame_control) &&
 468             is_multicast_ether_addr(hdr->addr1) &&
 469             mesh_rmc_check(hdr->addr4, msh_h_get(hdr, hdrlen), rx->sdata))
 470                 return RX_DROP_MONITOR;
 471 #undef msh_h_get
 472
 473         return RX_CONTINUE;
 474 }
 475
 476
 477 static ieee80211_rx_result debug_noinline
 478 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
 479 {
 480         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 481
 482         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 483         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 484                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
 485                              rx->sta->last_seq_ctrl[rx->queue] ==
 486                              hdr->seq_ctrl)) {
 487                         if (rx->flags & IEEE80211_RX_RA_MATCH) {
 488                                 rx->local->dot11FrameDuplicateCount++;
 489                                 rx->sta->num_duplicates++;
 490                         }
 491                         return RX_DROP_MONITOR;
 492                 } else
 493                         rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
 494         }
 495
 496         if (unlikely(rx->skb->len < 16)) {
 497                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 498                 return RX_DROP_MONITOR;
 499         }
 500
 501         /* Drop disallowed frame classes based on STA auth/assoc state;
 502          * IEEE 802.11, Chap 5.5.
 503          *
 504          * mac80211 filters only based on association state, i.e. it drops
 505          * Class 3 frames from not associated stations. hostapd sends
 506          * deauth/disassoc frames when needed. In addition, hostapd is
 507          * responsible for filtering on both auth and assoc states.
 508          */
 509
 510         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
 511                 return ieee80211_rx_mesh_check(rx);
 512
 513         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
 514                       ieee80211_is_pspoll(hdr->frame_control)) &&
 515                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
 516                      (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
 517                 if ((!ieee80211_has_fromds(hdr->frame_control) &&
 518                      !ieee80211_has_tods(hdr->frame_control) &&
 519                      ieee80211_is_data(hdr->frame_control)) ||
 520                     !(rx->flags & IEEE80211_RX_RA_MATCH)) {
 521                         /* Drop IBSS frames and frames for other hosts
 522                          * silently. */
 523                         return RX_DROP_MONITOR;
 524                 }
 525
 526                 return RX_DROP_MONITOR;
 527         }
 528
 529         return RX_CONTINUE;
 530 }
 531
 532
 533 static ieee80211_rx_result debug_noinline
 534 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
 535 {
 536         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 537         int keyidx;
 538         int hdrlen;
 539         ieee80211_rx_result result = RX_DROP_UNUSABLE;
 540         struct ieee80211_key *stakey = NULL;
 541
 542         /*
 543          * Key selection 101
 544          *
 545          * There are three types of keys:
 546          *  - GTK (group keys)
 547          *  - PTK (pairwise keys)
 548          *  - STK (station-to-station pairwise keys)
 549          *
 550          * When selecting a key, we have to distinguish between multicast
 551          * (including broadcast) and unicast frames, the latter can only
 552          * use PTKs and STKs while the former always use GTKs. Unless, of
 553          * course, actual WEP keys ("pre-RSNA") are used, then unicast
 554          * frames can also use key indizes like GTKs. Hence, if we don't
 555          * have a PTK/STK we check the key index for a WEP key.
 556          *
 557          * Note that in a regular BSS, multicast frames are sent by the
 558          * AP only, associated stations unicast the frame to the AP first
 559          * which then multicasts it on their behalf.
 560          *
 561          * There is also a slight problem in IBSS mode: GTKs are negotiated
 562          * with each station, that is something we don't currently handle.
 563          * The spec seems to expect that one negotiates the same key with
 564          * every station but there's no such requirement; VLANs could be
 565          * possible.
 566          */
 567
 568         if (!ieee80211_has_protected(hdr->frame_control))
 569                 return RX_CONTINUE;
 570
 571         /*
 572          * No point in finding a key and decrypting if the frame is neither
 573          * addressed to us nor a multicast frame.
 574          */
 575         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
 576                 return RX_CONTINUE;
 577
 578         if (rx->sta)
 579                 stakey = rcu_dereference(rx->sta->key);
 580
 581         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
 582                 rx->key = stakey;
 583         } else {
 584                 /*
 585                  * The device doesn't give us the IV so we won't be
 586                  * able to look up the key. That's ok though, we
 587                  * don't need to decrypt the frame, we just won't
 588                  * be able to keep statistics accurate.
 589                  * Except for key threshold notifications, should
 590                  * we somehow allow the driver to tell us which key
 591                  * the hardware used if this flag is set?
 592                  */
 593                 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
 594                     (rx->status->flag & RX_FLAG_IV_STRIPPED))
 595                         return RX_CONTINUE;
 596
 597                 hdrlen = ieee80211_hdrlen(hdr->frame_control);
 598
 599                 if (rx->skb->len < 8 + hdrlen)
 600                         return RX_DROP_UNUSABLE; /* TODO: count this? */
 601
 602                 /*
 603                  * no need to call ieee80211_wep_get_keyidx,
 604                  * it verifies a bunch of things we've done already
 605                  */
 606                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
 607
 608                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
 609
 610                 /*
 611                  * RSNA-protected unicast frames should always be sent with
 612                  * pairwise or station-to-station keys, but for WEP we allow
 613                  * using a key index as well.
 614                  */
 615                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
 616                     !is_multicast_ether_addr(hdr->addr1))
 617                         rx->key = NULL;
 618         }
 619
 620         if (rx->key) {
 621                 rx->key->tx_rx_count++;
 622                 /* TODO: add threshold stuff again */
 623         } else {
 624                 return RX_DROP_MONITOR;
 625         }
 626
 627         /* Check for weak IVs if possible */
 628         if (rx->sta && rx->key->conf.alg == ALG_WEP &&
 629             ieee80211_is_data(hdr->frame_control) &&
 630             (!(rx->status->flag & RX_FLAG_IV_STRIPPED) ||
 631              !(rx->status->flag & RX_FLAG_DECRYPTED)) &&
 632             ieee80211_wep_is_weak_iv(rx->skb, rx->key))
 633                 rx->sta->wep_weak_iv_count++;
 634
 635         switch (rx->key->conf.alg) {
 636         case ALG_WEP:
 637                 result = ieee80211_crypto_wep_decrypt(rx);
 638                 break;
 639         case ALG_TKIP:
 640                 result = ieee80211_crypto_tkip_decrypt(rx);
 641                 break;
 642         case ALG_CCMP:
 643                 result = ieee80211_crypto_ccmp_decrypt(rx);
 644                 break;
 645         }
 646
 647         /* either the frame has been decrypted or will be dropped */
 648         rx->status->flag |= RX_FLAG_DECRYPTED;
 649
 650         return result;
 651 }
 652
 653 static void ap_sta_ps_start(struct sta_info *sta)
 654 {
 655         struct ieee80211_sub_if_data *sdata = sta->sdata;
 656         DECLARE_MAC_BUF(mac);
 657
 658         atomic_inc(&sdata->bss->num_sta_ps);
 659         set_and_clear_sta_flags(sta, WLAN_STA_PS, WLAN_STA_PSPOLL);
 660 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 661         printk(KERN_DEBUG "%s: STA %s aid %d enters power save mode\n",
 662                sdata->dev->name, print_mac(mac, sta->sta.addr), sta->sta.aid);
 663 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 664 }
 665
 666 static int ap_sta_ps_end(struct sta_info *sta)
 667 {
 668         struct ieee80211_sub_if_data *sdata = sta->sdata;
 669         struct ieee80211_local *local = sdata->local;
 670         struct sk_buff *skb;
 671         int sent = 0;
 672         struct ieee80211_tx_info *info;
 673         DECLARE_MAC_BUF(mac);
 674
 675         atomic_dec(&sdata->bss->num_sta_ps);
 676
 677         clear_sta_flags(sta, WLAN_STA_PS | WLAN_STA_PSPOLL);
 678
 679         if (!skb_queue_empty(&sta->ps_tx_buf))
 680                 sta_info_clear_tim_bit(sta);
 681
 682 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 683         printk(KERN_DEBUG "%s: STA %s aid %d exits power save mode\n",
 684                sdata->dev->name, print_mac(mac, sta->sta.addr), sta->sta.aid);
 685 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 686
 687         /* Send all buffered frames to the station */
 688         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
 689                 info = IEEE80211_SKB_CB(skb);
 690                 sent++;
 691                 info->flags |= IEEE80211_TX_CTL_REQUEUE;
 692                 dev_queue_xmit(skb);
 693         }
 694         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
 695                 info = IEEE80211_SKB_CB(skb);
 696                 local->total_ps_buffered--;
 697                 sent++;
 698 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 699                 printk(KERN_DEBUG "%s: STA %s aid %d send PS frame "
 700                        "since STA not sleeping anymore\n", sdata->dev->name,
 701                        print_mac(mac, sta->sta.addr), sta->sta.aid);
 702 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 703                 info->flags |= IEEE80211_TX_CTL_REQUEUE;
 704                 dev_queue_xmit(skb);
 705         }
 706
 707         return sent;
 708 }
 709
 710 static ieee80211_rx_result debug_noinline
 711 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
 712 {
 713         struct sta_info *sta = rx->sta;
 714         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 715
 716         if (!sta)
 717                 return RX_CONTINUE;
 718
 719         /* Update last_rx only for IBSS packets which are for the current
 720          * BSSID to avoid keeping the current IBSS network alive in cases where
 721          * other STAs are using different BSSID. */
 722         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
 723                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
 724                                                 NL80211_IFTYPE_ADHOC);
 725                 if (compare_ether_addr(bssid, rx->sdata->u.sta.bssid) == 0)
 726                         sta->last_rx = jiffies;
 727         } else
 728         if (!is_multicast_ether_addr(hdr->addr1) ||
 729             rx->sdata->vif.type == NL80211_IFTYPE_STATION) {
 730                 /* Update last_rx only for unicast frames in order to prevent
 731                  * the Probe Request frames (the only broadcast frames from a
 732                  * STA in infrastructure mode) from keeping a connection alive.
 733                  * Mesh beacons will update last_rx when if they are found to
 734                  * match the current local configuration when processed.
 735                  */
 736                 sta->last_rx = jiffies;
 737         }
 738
 739         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
 740                 return RX_CONTINUE;
 741
 742         sta->rx_fragments++;
 743         sta->rx_bytes += rx->skb->len;
 744         sta->last_signal = rx->status->signal;
 745         sta->last_qual = rx->status->qual;
 746         sta->last_noise = rx->status->noise;
 747
 748         if (!ieee80211_has_morefrags(hdr->frame_control) &&
 749             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
 750              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
 751                 /* Change STA power saving mode only in the end of a frame
 752                  * exchange sequence */
 753                 if (test_sta_flags(sta, WLAN_STA_PS) &&
 754                     !ieee80211_has_pm(hdr->frame_control))
 755                         rx->sent_ps_buffered += ap_sta_ps_end(sta);
 756                 else if (!test_sta_flags(sta, WLAN_STA_PS) &&
 757                          ieee80211_has_pm(hdr->frame_control))
 758                         ap_sta_ps_start(sta);
 759         }
 760
 761         /* Drop data::nullfunc frames silently, since they are used only to
 762          * control station power saving mode. */
 763         if (ieee80211_is_nullfunc(hdr->frame_control)) {
 764                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
 765                 /* Update counter and free packet here to avoid counting this
 766                  * as a dropped packed. */
 767                 sta->rx_packets++;
 768                 dev_kfree_skb(rx->skb);
 769                 return RX_QUEUED;
 770         }
 771
 772         return RX_CONTINUE;
 773 } /* ieee80211_rx_h_sta_process */
 774
 775 static inline struct ieee80211_fragment_entry *
 776 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
 777                          unsigned int frag, unsigned int seq, int rx_queue,
 778                          struct sk_buff **skb)
 779 {
 780         struct ieee80211_fragment_entry *entry;
 781         int idx;
 782
 783         idx = sdata->fragment_next;
 784         entry = &sdata->fragments[sdata->fragment_next++];
 785         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
 786                 sdata->fragment_next = 0;
 787
 788         if (!skb_queue_empty(&entry->skb_list)) {
 789 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 790                 struct ieee80211_hdr *hdr =
 791                         (struct ieee80211_hdr *) entry->skb_list.next->data;
 792                 DECLARE_MAC_BUF(mac);
 793                 DECLARE_MAC_BUF(mac2);
 794                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
 795                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
 796                        "addr1=%s addr2=%s\n",
 797                        sdata->dev->name, idx,
 798                        jiffies - entry->first_frag_time, entry->seq,
 799                        entry->last_frag, print_mac(mac, hdr->addr1),
 800                        print_mac(mac2, hdr->addr2));
 801 #endif
 802                 __skb_queue_purge(&entry->skb_list);
 803         }
 804
 805         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
 806         *skb = NULL;
 807         entry->first_frag_time = jiffies;
 808         entry->seq = seq;
 809         entry->rx_queue = rx_queue;
 810         entry->last_frag = frag;
 811         entry->ccmp = 0;
 812         entry->extra_len = 0;
 813
 814         return entry;
 815 }
 816
 817 static inline struct ieee80211_fragment_entry *
 818 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
 819                           unsigned int frag, unsigned int seq,
 820                           int rx_queue, struct ieee80211_hdr *hdr)
 821 {
 822         struct ieee80211_fragment_entry *entry;
 823         int i, idx;
 824
 825         idx = sdata->fragment_next;
 826         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
 827                 struct ieee80211_hdr *f_hdr;
 828
 829                 idx--;
 830                 if (idx < 0)
 831                         idx = IEEE80211_FRAGMENT_MAX - 1;
 832
 833                 entry = &sdata->fragments[idx];
 834                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
 835                     entry->rx_queue != rx_queue ||
 836                     entry->last_frag + 1 != frag)
 837                         continue;
 838
 839                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
 840
 841                 /*
 842                  * Check ftype and addresses are equal, else check next fragment
 843                  */
 844                 if (((hdr->frame_control ^ f_hdr->frame_control) &
 845                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
 846                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
 847                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
 848                         continue;
 849
 850                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
 851                         __skb_queue_purge(&entry->skb_list);
 852                         continue;
 853                 }
 854                 return entry;
 855         }
 856
 857         return NULL;
 858 }
 859
 860 static ieee80211_rx_result debug_noinline
 861 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
 862 {
 863         struct ieee80211_hdr *hdr;
 864         u16 sc;
 865         __le16 fc;
 866         unsigned int frag, seq;
 867         struct ieee80211_fragment_entry *entry;
 868         struct sk_buff *skb;
 869         DECLARE_MAC_BUF(mac);
 870
 871         hdr = (struct ieee80211_hdr *)rx->skb->data;
 872         fc = hdr->frame_control;
 873         sc = le16_to_cpu(hdr->seq_ctrl);
 874         frag = sc & IEEE80211_SCTL_FRAG;
 875
 876         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
 877                    (rx->skb)->len < 24 ||
 878                    is_multicast_ether_addr(hdr->addr1))) {
 879                 /* not fragmented */
 880                 goto out;
 881         }
 882         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
 883
 884         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
 885
 886         if (frag == 0) {
 887                 /* This is the first fragment of a new frame. */
 888                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
 889                                                  rx->queue, &(rx->skb));
 890                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
 891                     ieee80211_has_protected(fc)) {
 892                         /* Store CCMP PN so that we can verify that the next
 893                          * fragment has a sequential PN value. */
 894                         entry->ccmp = 1;
 895                         memcpy(entry->last_pn,
 896                                rx->key->u.ccmp.rx_pn[rx->queue],
 897                                CCMP_PN_LEN);
 898                 }
 899                 return RX_QUEUED;
 900         }
 901
 902         /* This is a fragment for a frame that should already be pending in
 903          * fragment cache. Add this fragment to the end of the pending entry.
 904          */
 905         entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
 906         if (!entry) {
 907                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 908                 return RX_DROP_MONITOR;
 909         }
 910
 911         /* Verify that MPDUs within one MSDU have sequential PN values.
 912          * (IEEE 802.11i, 8.3.3.4.5) */
 913         if (entry->ccmp) {
 914                 int i;
 915                 u8 pn[CCMP_PN_LEN], *rpn;
 916                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
 917                         return RX_DROP_UNUSABLE;
 918                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
 919                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
 920                         pn[i]++;
 921                         if (pn[i])
 922                                 break;
 923                 }
 924                 rpn = rx->key->u.ccmp.rx_pn[rx->queue];
 925                 if (memcmp(pn, rpn, CCMP_PN_LEN))
 926                         return RX_DROP_UNUSABLE;
 927                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
 928         }
 929
 930         skb_pull(rx->skb, ieee80211_hdrlen(fc));
 931         __skb_queue_tail(&entry->skb_list, rx->skb);
 932         entry->last_frag = frag;
 933         entry->extra_len += rx->skb->len;
 934         if (ieee80211_has_morefrags(fc)) {
 935                 rx->skb = NULL;
 936                 return RX_QUEUED;
 937         }
 938
 939         rx->skb = __skb_dequeue(&entry->skb_list);
 940         if (skb_tailroom(rx->skb) < entry->extra_len) {
 941                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
 942                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
 943                                               GFP_ATOMIC))) {
 944                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
 945                         __skb_queue_purge(&entry->skb_list);
 946                         return RX_DROP_UNUSABLE;
 947                 }
 948         }
 949         while ((skb = __skb_dequeue(&entry->skb_list))) {
 950                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
 951                 dev_kfree_skb(skb);
 952         }
 953
 954         /* Complete frame has been reassembled - process it now */
 955         rx->flags |= IEEE80211_RX_FRAGMENTED;
 956
 957  out:
 958         if (rx->sta)
 959                 rx->sta->rx_packets++;
 960         if (is_multicast_ether_addr(hdr->addr1))
 961                 rx->local->dot11MulticastReceivedFrameCount++;
 962         else
 963                 ieee80211_led_rx(rx->local);
 964         return RX_CONTINUE;
 965 }
 966
 967 static ieee80211_rx_result debug_noinline
 968 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
 969 {
 970         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
 971         struct sk_buff *skb;
 972         int no_pending_pkts;
 973         DECLARE_MAC_BUF(mac);
 974         __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
 975
 976         if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
 977                    !(rx->flags & IEEE80211_RX_RA_MATCH)))
 978                 return RX_CONTINUE;
 979
 980         if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
 981             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
 982                 return RX_DROP_UNUSABLE;
 983
 984         skb = skb_dequeue(&rx->sta->tx_filtered);
 985         if (!skb) {
 986                 skb = skb_dequeue(&rx->sta->ps_tx_buf);
 987                 if (skb)
 988                         rx->local->total_ps_buffered--;
 989         }
 990         no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
 991                 skb_queue_empty(&rx->sta->ps_tx_buf);
 992
 993         if (skb) {
 994                 struct ieee80211_hdr *hdr =
 995                         (struct ieee80211_hdr *) skb->data;
 996
 997                 /*
 998                  * Tell TX path to send one frame even though the STA may
 999                  * still remain is PS mode after this frame exchange.
1000                  */
1001                 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1002
1003 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1004                 printk(KERN_DEBUG "STA %s aid %d: PS Poll (entries after %d)\n",
1005                        print_mac(mac, rx->sta->sta.addr), rx->sta->sta.aid,
1006                        skb_queue_len(&rx->sta->ps_tx_buf));
1007 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1008
1009                 /* Use MoreData flag to indicate whether there are more
1010                  * buffered frames for this STA */
1011                 if (no_pending_pkts)
1012                         hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
1013                 else
1014                         hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1015
1016                 dev_queue_xmit(skb);
1017
1018                 if (no_pending_pkts)
1019                         sta_info_clear_tim_bit(rx->sta);
1020 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1021         } else if (!rx->sent_ps_buffered) {
1022                 /*
1023                  * FIXME: This can be the result of a race condition between
1024                  *        us expiring a frame and the station polling for it.
1025                  *        Should we send it a null-func frame indicating we
1026                  *        have nothing buffered for it?
1027                  */
1028                 printk(KERN_DEBUG "%s: STA %s sent PS Poll even "
1029                        "though there are no buffered frames for it\n",
1030                        rx->dev->name, print_mac(mac, rx->sta->sta.addr));
1031 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1032         }
1033
1034         /* Free PS Poll skb here instead of returning RX_DROP that would
1035          * count as an dropped frame. */
1036         dev_kfree_skb(rx->skb);
1037
1038         return RX_QUEUED;
1039 }
1040
1041 static ieee80211_rx_result debug_noinline
1042 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1043 {
1044         u8 *data = rx->skb->data;
1045         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1046
1047         if (!ieee80211_is_data_qos(hdr->frame_control))
1048                 return RX_CONTINUE;
1049
1050         /* remove the qos control field, update frame type and meta-data */
1051         memmove(data + IEEE80211_QOS_CTL_LEN, data,
1052                 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1053         hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1054         /* change frame type to non QOS */
1055         hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1056
1057         return RX_CONTINUE;
1058 }
1059
1060 static int
1061 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1062 {
1063         if (unlikely(!rx->sta ||
1064             !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1065                 return -EACCES;
1066
1067         return 0;
1068 }
1069
1070 static int
1071 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1072 {
1073         /*
1074          * Pass through unencrypted frames if the hardware has
1075          * decrypted them already.
1076          */
1077         if (rx->status->flag & RX_FLAG_DECRYPTED)
1078                 return 0;
1079
1080         /* Drop unencrypted frames if key is set. */
1081         if (unlikely(!ieee80211_has_protected(fc) &&
1082                      !ieee80211_is_nullfunc(fc) &&
1083                      (rx->key || rx->sdata->drop_unencrypted)))
1084                 return -EACCES;
1085
1086         return 0;
1087 }
1088
1089 static int
1090 ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1091 {
1092         struct net_device *dev = rx->dev;
1093         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
1094         u16 hdrlen, ethertype;
1095         u8 *payload;
1096         u8 dst[ETH_ALEN];
1097         u8 src[ETH_ALEN] __aligned(2);
1098         struct sk_buff *skb = rx->skb;
1099         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1100         DECLARE_MAC_BUF(mac);
1101         DECLARE_MAC_BUF(mac2);
1102         DECLARE_MAC_BUF(mac3);
1103         DECLARE_MAC_BUF(mac4);
1104
1105         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1106                 return -1;
1107
1108         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1109
1110         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
1111          * header
1112          * IEEE 802.11 address fields:
1113          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
1114          *   0     0   DA    SA    BSSID n/a
1115          *   0     1   DA    BSSID SA    n/a
1116          *   1     0   BSSID SA    DA    n/a
1117          *   1     1   RA    TA    DA    SA
1118          */
1119         memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
1120         memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);
1121
1122         switch (hdr->frame_control &
1123                 cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
1124         case __constant_cpu_to_le16(IEEE80211_FCTL_TODS):
1125                 if (unlikely(sdata->vif.type != NL80211_IFTYPE_AP &&
1126                              sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1127                         return -1;
1128                 break;
1129         case __constant_cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
1130                 if (unlikely(sdata->vif.type != NL80211_IFTYPE_WDS &&
1131                              sdata->vif.type != NL80211_IFTYPE_MESH_POINT))
1132                         return -1;
1133                 if (ieee80211_vif_is_mesh(&sdata->vif)) {
1134                         struct ieee80211s_hdr *meshdr = (struct ieee80211s_hdr *)
1135                                 (skb->data + hdrlen);
1136                         hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
1137                         if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
1138                                 memcpy(dst, meshdr->eaddr1, ETH_ALEN);
1139                                 memcpy(src, meshdr->eaddr2, ETH_ALEN);
1140                         }
1141                 }
1142                 break;
1143         case __constant_cpu_to_le16(IEEE80211_FCTL_FROMDS):
1144                 if (sdata->vif.type != NL80211_IFTYPE_STATION ||
1145                     (is_multicast_ether_addr(dst) &&
1146                      !compare_ether_addr(src, dev->dev_addr)))
1147                         return -1;
1148                 break;
1149         case __constant_cpu_to_le16(0):
1150                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1151                         return -1;
1152                 break;
1153         }
1154
1155         if (unlikely(skb->len - hdrlen < 8))
1156                 return -1;
1157
1158         payload = skb->data + hdrlen;
1159         ethertype = (payload[6] << 8) | payload[7];
1160
1161         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1162                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1163                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1164                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1165                  * replace EtherType */
1166                 skb_pull(skb, hdrlen + 6);
1167                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1168                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1169         } else {
1170                 struct ethhdr *ehdr;
1171                 __be16 len;
1172
1173                 skb_pull(skb, hdrlen);
1174                 len = htons(skb->len);
1175                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1176                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1177                 memcpy(ehdr->h_source, src, ETH_ALEN);
1178                 ehdr->h_proto = len;
1179         }
1180         return 0;
1181 }
1182
1183 /*
1184  * requires that rx->skb is a frame with ethernet header
1185  */
1186 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1187 {
1188         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1189                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1190         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1191
1192         /*
1193          * Allow EAPOL frames to us/the PAE group address regardless
1194          * of whether the frame was encrypted or not.
1195          */
1196         if (ehdr->h_proto == htons(ETH_P_PAE) &&
1197             (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
1198              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1199                 return true;
1200
1201         if (ieee80211_802_1x_port_control(rx) ||
1202             ieee80211_drop_unencrypted(rx, fc))
1203                 return false;
1204
1205         return true;
1206 }
1207
1208 /*
1209  * requires that rx->skb is a frame with ethernet header
1210  */
1211 static void
1212 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1213 {
1214         struct net_device *dev = rx->dev;
1215         struct ieee80211_local *local = rx->local;
1216         struct sk_buff *skb, *xmit_skb;
1217         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1218         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1219         struct sta_info *dsta;
1220
1221         skb = rx->skb;
1222         xmit_skb = NULL;
1223
1224         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1225              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1226             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1227             (rx->flags & IEEE80211_RX_RA_MATCH)) {
1228                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1229                         /*
1230                          * send multicast frames both to higher layers in
1231                          * local net stack and back to the wireless medium
1232                          */
1233                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1234                         if (!xmit_skb && net_ratelimit())
1235                                 printk(KERN_DEBUG "%s: failed to clone "
1236                                        "multicast frame\n", dev->name);
1237                 } else {
1238                         dsta = sta_info_get(local, skb->data);
1239                         if (dsta && dsta->sdata->dev == dev) {
1240                                 /*
1241                                  * The destination station is associated to
1242                                  * this AP (in this VLAN), so send the frame
1243                                  * directly to it and do not pass it to local
1244                                  * net stack.
1245                                  */
1246                                 xmit_skb = skb;
1247                                 skb = NULL;
1248                         }
1249                 }
1250         }
1251
1252         if (skb) {
1253                 /* deliver to local stack */
1254                 skb->protocol = eth_type_trans(skb, dev);
1255                 memset(skb->cb, 0, sizeof(skb->cb));
1256                 netif_rx(skb);
1257         }
1258
1259         if (xmit_skb) {
1260                 /* send to wireless media */
1261                 xmit_skb->protocol = htons(ETH_P_802_3);
1262                 skb_reset_network_header(xmit_skb);
1263                 skb_reset_mac_header(xmit_skb);
1264                 dev_queue_xmit(xmit_skb);
1265         }
1266 }
1267
1268 static ieee80211_rx_result debug_noinline
1269 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1270 {
1271         struct net_device *dev = rx->dev;
1272         struct ieee80211_local *local = rx->local;
1273         u16 ethertype;
1274         u8 *payload;
1275         struct sk_buff *skb = rx->skb, *frame = NULL;
1276         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1277         __le16 fc = hdr->frame_control;
1278         const struct ethhdr *eth;
1279         int remaining, err;
1280         u8 dst[ETH_ALEN];
1281         u8 src[ETH_ALEN];
1282         DECLARE_MAC_BUF(mac);
1283
1284         if (unlikely(!ieee80211_is_data(fc)))
1285                 return RX_CONTINUE;
1286
1287         if (unlikely(!ieee80211_is_data_present(fc)))
1288                 return RX_DROP_MONITOR;
1289
1290         if (!(rx->flags & IEEE80211_RX_AMSDU))
1291                 return RX_CONTINUE;
1292
1293         err = ieee80211_data_to_8023(rx);
1294         if (unlikely(err))
1295                 return RX_DROP_UNUSABLE;
1296
1297         skb->dev = dev;
1298
1299         dev->stats.rx_packets++;
1300         dev->stats.rx_bytes += skb->len;
1301
1302         /* skip the wrapping header */
1303         eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
1304         if (!eth)
1305                 return RX_DROP_UNUSABLE;
1306
1307         while (skb != frame) {
1308                 u8 padding;
1309                 __be16 len = eth->h_proto;
1310                 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
1311
1312                 remaining = skb->len;
1313                 memcpy(dst, eth->h_dest, ETH_ALEN);
1314                 memcpy(src, eth->h_source, ETH_ALEN);
1315
1316                 padding = ((4 - subframe_len) & 0x3);
1317                 /* the last MSDU has no padding */
1318                 if (subframe_len > remaining)
1319                         return RX_DROP_UNUSABLE;
1320
1321                 skb_pull(skb, sizeof(struct ethhdr));
1322                 /* if last subframe reuse skb */
1323                 if (remaining <= subframe_len + padding)
1324                         frame = skb;
1325                 else {
1326                         frame = dev_alloc_skb(local->hw.extra_tx_headroom +
1327                                               subframe_len);
1328
1329                         if (frame == NULL)
1330                                 return RX_DROP_UNUSABLE;
1331
1332                         skb_reserve(frame, local->hw.extra_tx_headroom +
1333                                     sizeof(struct ethhdr));
1334                         memcpy(skb_put(frame, ntohs(len)), skb->data,
1335                                 ntohs(len));
1336
1337                         eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
1338                                                         padding);
1339                         if (!eth) {
1340                                 dev_kfree_skb(frame);
1341                                 return RX_DROP_UNUSABLE;
1342                         }
1343                 }
1344
1345                 skb_reset_network_header(frame);
1346                 frame->dev = dev;
1347                 frame->priority = skb->priority;
1348                 rx->skb = frame;
1349
1350                 payload = frame->data;
1351                 ethertype = (payload[6] << 8) | payload[7];
1352
1353                 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1354                             ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1355                            compare_ether_addr(payload,
1356                                               bridge_tunnel_header) == 0)) {
1357                         /* remove RFC1042 or Bridge-Tunnel
1358                          * encapsulation and replace EtherType */
1359                         skb_pull(frame, 6);
1360                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1361                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1362                 } else {
1363                         memcpy(skb_push(frame, sizeof(__be16)),
1364                                &len, sizeof(__be16));
1365                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1366                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1367                 }
1368
1369                 if (!ieee80211_frame_allowed(rx, fc)) {
1370                         if (skb == frame) /* last frame */
1371                                 return RX_DROP_UNUSABLE;
1372                         dev_kfree_skb(frame);
1373                         continue;
1374                 }
1375
1376                 ieee80211_deliver_skb(rx);
1377         }
1378
1379         return RX_QUEUED;
1380 }
1381
1382 static ieee80211_rx_result debug_noinline
1383 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1384 {
1385         struct ieee80211_hdr *hdr;
1386         struct ieee80211s_hdr *mesh_hdr;
1387         unsigned int hdrlen;
1388         struct sk_buff *skb = rx->skb, *fwd_skb;
1389
1390         hdr = (struct ieee80211_hdr *) skb->data;
1391         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1392         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1393
1394         if (!ieee80211_is_data(hdr->frame_control))
1395                 return RX_CONTINUE;
1396
1397         if (!mesh_hdr->ttl)
1398                 /* illegal frame */
1399                 return RX_DROP_MONITOR;
1400
1401         if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6){
1402                 struct ieee80211_sub_if_data *sdata;
1403                 struct mesh_path *mppath;
1404
1405                 sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1406                 rcu_read_lock();
1407                 mppath = mpp_path_lookup(mesh_hdr->eaddr2, sdata);
1408                 if (!mppath) {
1409                         mpp_path_add(mesh_hdr->eaddr2, hdr->addr4, sdata);
1410                 } else {
1411                         spin_lock_bh(&mppath->state_lock);
1412                         mppath->exp_time = jiffies;
1413                         if (compare_ether_addr(mppath->mpp, hdr->addr4) != 0)
1414                                 memcpy(mppath->mpp, hdr->addr4, ETH_ALEN);
1415                         spin_unlock_bh(&mppath->state_lock);
1416                 }
1417                 rcu_read_unlock();
1418         }
1419
1420         if (compare_ether_addr(rx->dev->dev_addr, hdr->addr3) == 0)
1421                 return RX_CONTINUE;
1422
1423         mesh_hdr->ttl--;
1424
1425         if (rx->flags & IEEE80211_RX_RA_MATCH) {
1426                 if (!mesh_hdr->ttl)
1427                         IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1428                                                      dropped_frames_ttl);
1429                 else {
1430                         struct ieee80211_hdr *fwd_hdr;
1431                         fwd_skb = skb_copy(skb, GFP_ATOMIC);
1432
1433                         if (!fwd_skb && net_ratelimit())
1434                                 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1435                                                    rx->dev->name);
1436
1437                         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1438                         /*
1439                          * Save TA to addr1 to send TA a path error if a
1440                          * suitable next hop is not found
1441                          */
1442                         memcpy(fwd_hdr->addr1, fwd_hdr->addr2, ETH_ALEN);
1443                         memcpy(fwd_hdr->addr2, rx->dev->dev_addr, ETH_ALEN);
1444                         fwd_skb->dev = rx->local->mdev;
1445                         fwd_skb->iif = rx->dev->ifindex;
1446                         dev_queue_xmit(fwd_skb);
1447                 }
1448         }
1449
1450         if (is_multicast_ether_addr(hdr->addr3) ||
1451             rx->dev->flags & IFF_PROMISC)
1452                 return RX_CONTINUE;
1453         else
1454                 return RX_DROP_MONITOR;
1455 }
1456
1457
1458 static ieee80211_rx_result debug_noinline
1459 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1460 {
1461         struct net_device *dev = rx->dev;
1462         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1463         __le16 fc = hdr->frame_control;
1464         int err;
1465
1466         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1467                 return RX_CONTINUE;
1468
1469         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1470                 return RX_DROP_MONITOR;
1471
1472         err = ieee80211_data_to_8023(rx);
1473         if (unlikely(err))
1474                 return RX_DROP_UNUSABLE;
1475
1476         if (!ieee80211_frame_allowed(rx, fc))
1477                 return RX_DROP_MONITOR;
1478
1479         rx->skb->dev = dev;
1480
1481         dev->stats.rx_packets++;
1482         dev->stats.rx_bytes += rx->skb->len;
1483
1484         ieee80211_deliver_skb(rx);
1485
1486         return RX_QUEUED;
1487 }
1488
1489 static ieee80211_rx_result debug_noinline
1490 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
1491 {
1492         struct ieee80211_local *local = rx->local;
1493         struct ieee80211_hw *hw = &local->hw;
1494         struct sk_buff *skb = rx->skb;
1495         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1496         struct tid_ampdu_rx *tid_agg_rx;
1497         u16 start_seq_num;
1498         u16 tid;
1499
1500         if (likely(!ieee80211_is_ctl(bar->frame_control)))
1501                 return RX_CONTINUE;
1502
1503         if (ieee80211_is_back_req(bar->frame_control)) {
1504                 if (!rx->sta)
1505                         return RX_CONTINUE;
1506                 tid = le16_to_cpu(bar->control) >> 12;
1507                 if (rx->sta->ampdu_mlme.tid_state_rx[tid]
1508                                         != HT_AGG_STATE_OPERATIONAL)
1509                         return RX_CONTINUE;
1510                 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid];
1511
1512                 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1513
1514                 /* reset session timer */
1515                 if (tid_agg_rx->timeout) {
1516                         unsigned long expires =
1517                                 jiffies + (tid_agg_rx->timeout / 1000) * HZ;
1518                         mod_timer(&tid_agg_rx->session_timer, expires);
1519                 }
1520
1521                 /* manage reordering buffer according to requested */
1522                 /* sequence number */
1523                 rcu_read_lock();
1524                 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL,
1525                                                  start_seq_num, 1);
1526                 rcu_read_unlock();
1527                 return RX_DROP_UNUSABLE;
1528         }
1529
1530         return RX_CONTINUE;
1531 }
1532
1533 static ieee80211_rx_result debug_noinline
1534 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
1535 {
1536         struct ieee80211_local *local = rx->local;
1537         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1538         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1539         int len = rx->skb->len;
1540
1541         if (!ieee80211_is_action(mgmt->frame_control))
1542                 return RX_CONTINUE;
1543
1544         if (!rx->sta)
1545                 return RX_DROP_MONITOR;
1546
1547         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1548                 return RX_DROP_MONITOR;
1549
1550         /* all categories we currently handle have action_code */
1551         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
1552                 return RX_DROP_MONITOR;
1553
1554         /*
1555          * FIXME: revisit this, I'm sure we should handle most
1556          *        of these frames in other modes as well!
1557          */
1558         if (sdata->vif.type != NL80211_IFTYPE_STATION &&
1559             sdata->vif.type != NL80211_IFTYPE_ADHOC)
1560                 return RX_DROP_MONITOR;
1561
1562         switch (mgmt->u.action.category) {
1563         case WLAN_CATEGORY_BACK:
1564                 switch (mgmt->u.action.u.addba_req.action_code) {
1565                 case WLAN_ACTION_ADDBA_REQ:
1566                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1567                                    sizeof(mgmt->u.action.u.addba_req)))
1568                                 return RX_DROP_MONITOR;
1569                         ieee80211_process_addba_request(local, rx->sta, mgmt, len);
1570                         break;
1571                 case WLAN_ACTION_ADDBA_RESP:
1572                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1573                                    sizeof(mgmt->u.action.u.addba_resp)))
1574                                 return RX_DROP_MONITOR;
1575                         ieee80211_process_addba_resp(local, rx->sta, mgmt, len);
1576                         break;
1577                 case WLAN_ACTION_DELBA:
1578                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1579                                    sizeof(mgmt->u.action.u.delba)))
1580                                 return RX_DROP_MONITOR;
1581                         ieee80211_process_delba(sdata, rx->sta, mgmt, len);
1582                         break;
1583                 }
1584                 break;
1585         case WLAN_CATEGORY_SPECTRUM_MGMT:
1586                 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
1587                         return RX_DROP_MONITOR;
1588                 switch (mgmt->u.action.u.measurement.action_code) {
1589                 case WLAN_ACTION_SPCT_MSR_REQ:
1590                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1591                                    sizeof(mgmt->u.action.u.measurement)))
1592                                 return RX_DROP_MONITOR;
1593                         ieee80211_process_measurement_req(sdata, mgmt, len);
1594                         break;
1595                 }
1596                 break;
1597         default:
1598                 return RX_CONTINUE;
1599         }
1600
1601         rx->sta->rx_packets++;
1602         dev_kfree_skb(rx->skb);
1603         return RX_QUEUED;
1604 }
1605
1606 static ieee80211_rx_result debug_noinline
1607 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
1608 {
1609         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1610
1611         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1612                 return RX_DROP_MONITOR;
1613
1614         if (ieee80211_vif_is_mesh(&sdata->vif))
1615                 return ieee80211_mesh_rx_mgmt(sdata, rx->skb, rx->status);
1616
1617         if (sdata->vif.type != NL80211_IFTYPE_STATION &&
1618             sdata->vif.type != NL80211_IFTYPE_ADHOC)
1619                 return RX_DROP_MONITOR;
1620
1621         if (sdata->flags & IEEE80211_SDATA_USERSPACE_MLME)
1622                 return RX_DROP_MONITOR;
1623
1624         ieee80211_sta_rx_mgmt(sdata, rx->skb, rx->status);
1625         return RX_QUEUED;
1626 }
1627
1628 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1629                                             struct ieee80211_hdr *hdr,
1630                                             struct ieee80211_rx_data *rx)
1631 {
1632         int keyidx;
1633         unsigned int hdrlen;
1634         DECLARE_MAC_BUF(mac);
1635         DECLARE_MAC_BUF(mac2);
1636
1637         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1638         if (rx->skb->len >= hdrlen + 4)
1639                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1640         else
1641                 keyidx = -1;
1642
1643         if (!rx->sta) {
1644                 /*
1645                  * Some hardware seem to generate incorrect Michael MIC
1646                  * reports; ignore them to avoid triggering countermeasures.
1647                  */
1648                 goto ignore;
1649         }
1650
1651         if (!ieee80211_has_protected(hdr->frame_control))
1652                 goto ignore;
1653
1654         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
1655                 /*
1656                  * APs with pairwise keys should never receive Michael MIC
1657                  * errors for non-zero keyidx because these are reserved for
1658                  * group keys and only the AP is sending real multicast
1659                  * frames in the BSS.
1660                  */
1661                 goto ignore;
1662         }
1663
1664         if (!ieee80211_is_data(hdr->frame_control) &&
1665             !ieee80211_is_auth(hdr->frame_control))
1666                 goto ignore;
1667
1668         mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr);
1669  ignore:
1670         dev_kfree_skb(rx->skb);
1671         rx->skb = NULL;
1672 }
1673
1674 /* TODO: use IEEE80211_RX_FRAGMENTED */
1675 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx)
1676 {
1677         struct ieee80211_sub_if_data *sdata;
1678         struct ieee80211_local *local = rx->local;
1679         struct ieee80211_rtap_hdr {
1680                 struct ieee80211_radiotap_header hdr;
1681                 u8 flags;
1682                 u8 rate;
1683                 __le16 chan_freq;
1684                 __le16 chan_flags;
1685         } __attribute__ ((packed)) *rthdr;
1686         struct sk_buff *skb = rx->skb, *skb2;
1687         struct net_device *prev_dev = NULL;
1688         struct ieee80211_rx_status *status = rx->status;
1689
1690         if (rx->flags & IEEE80211_RX_CMNTR_REPORTED)
1691                 goto out_free_skb;
1692
1693         if (skb_headroom(skb) < sizeof(*rthdr) &&
1694             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
1695                 goto out_free_skb;
1696
1697         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
1698         memset(rthdr, 0, sizeof(*rthdr));
1699         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
1700         rthdr->hdr.it_present =
1701                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
1702                             (1 << IEEE80211_RADIOTAP_RATE) |
1703                             (1 << IEEE80211_RADIOTAP_CHANNEL));
1704
1705         rthdr->rate = rx->rate->bitrate / 5;
1706         rthdr->chan_freq = cpu_to_le16(status->freq);
1707
1708         if (status->band == IEEE80211_BAND_5GHZ)
1709                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
1710                                                 IEEE80211_CHAN_5GHZ);
1711         else
1712                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
1713                                                 IEEE80211_CHAN_2GHZ);
1714
1715         skb_set_mac_header(skb, 0);
1716         skb->ip_summed = CHECKSUM_UNNECESSARY;
1717         skb->pkt_type = PACKET_OTHERHOST;
1718         skb->protocol = htons(ETH_P_802_2);
1719
1720         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1721                 if (!netif_running(sdata->dev))
1722                         continue;
1723
1724                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
1725                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
1726                         continue;
1727
1728                 if (prev_dev) {
1729                         skb2 = skb_clone(skb, GFP_ATOMIC);
1730                         if (skb2) {
1731                                 skb2->dev = prev_dev;
1732                                 netif_rx(skb2);
1733                         }
1734                 }
1735
1736                 prev_dev = sdata->dev;
1737                 sdata->dev->stats.rx_packets++;
1738                 sdata->dev->stats.rx_bytes += skb->len;
1739         }
1740
1741         if (prev_dev) {
1742                 skb->dev = prev_dev;
1743                 netif_rx(skb);
1744                 skb = NULL;
1745         } else
1746                 goto out_free_skb;
1747
1748         rx->flags |= IEEE80211_RX_CMNTR_REPORTED;
1749         return;
1750
1751  out_free_skb:
1752         dev_kfree_skb(skb);
1753 }
1754
1755
1756 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
1757                                          struct ieee80211_rx_data *rx,
1758                                          struct sk_buff *skb)
1759 {
1760         ieee80211_rx_result res = RX_DROP_MONITOR;
1761
1762         rx->skb = skb;
1763         rx->sdata = sdata;
1764         rx->dev = sdata->dev;
1765
1766 #define CALL_RXH(rxh)                   \
1767         do {                            \
1768                 res = rxh(rx);          \
1769                 if (res != RX_CONTINUE) \
1770                         goto rxh_done;  \
1771         } while (0);
1772
1773         CALL_RXH(ieee80211_rx_h_passive_scan)
1774         CALL_RXH(ieee80211_rx_h_check)
1775         CALL_RXH(ieee80211_rx_h_decrypt)
1776         CALL_RXH(ieee80211_rx_h_sta_process)
1777         CALL_RXH(ieee80211_rx_h_defragment)
1778         CALL_RXH(ieee80211_rx_h_ps_poll)
1779         CALL_RXH(ieee80211_rx_h_michael_mic_verify)
1780         /* must be after MMIC verify so header is counted in MPDU mic */
1781         CALL_RXH(ieee80211_rx_h_remove_qos_control)
1782         CALL_RXH(ieee80211_rx_h_amsdu)
1783         if (ieee80211_vif_is_mesh(&sdata->vif))
1784                 CALL_RXH(ieee80211_rx_h_mesh_fwding);
1785         CALL_RXH(ieee80211_rx_h_data)
1786         CALL_RXH(ieee80211_rx_h_ctrl)
1787         CALL_RXH(ieee80211_rx_h_action)
1788         CALL_RXH(ieee80211_rx_h_mgmt)
1789
1790 #undef CALL_RXH
1791
1792  rxh_done:
1793         switch (res) {
1794         case RX_DROP_MONITOR:
1795                 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
1796                 if (rx->sta)
1797                         rx->sta->rx_dropped++;
1798                 /* fall through */
1799         case RX_CONTINUE:
1800                 ieee80211_rx_cooked_monitor(rx);
1801                 break;
1802         case RX_DROP_UNUSABLE:
1803                 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
1804                 if (rx->sta)
1805                         rx->sta->rx_dropped++;
1806                 dev_kfree_skb(rx->skb);
1807                 break;
1808         case RX_QUEUED:
1809                 I802_DEBUG_INC(sdata->local->rx_handlers_queued);
1810                 break;
1811         }
1812 }
1813
1814 /* main receive path */
1815
1816 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
1817                                 u8 *bssid, struct ieee80211_rx_data *rx,
1818                                 struct ieee80211_hdr *hdr)
1819 {
1820         int multicast = is_multicast_ether_addr(hdr->addr1);
1821
1822         switch (sdata->vif.type) {
1823         case NL80211_IFTYPE_STATION:
1824                 if (!bssid)
1825                         return 0;
1826                 if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1827                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
1828                                 return 0;
1829                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1830                 } else if (!multicast &&
1831                            compare_ether_addr(sdata->dev->dev_addr,
1832                                               hdr->addr1) != 0) {
1833                         if (!(sdata->dev->flags & IFF_PROMISC))
1834                                 return 0;
1835                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1836                 }
1837                 break;
1838         case NL80211_IFTYPE_ADHOC:
1839                 if (!bssid)
1840                         return 0;
1841                 if (ieee80211_is_beacon(hdr->frame_control)) {
1842                         return 1;
1843                 }
1844                 else if (!ieee80211_bssid_match(bssid, sdata->u.sta.bssid)) {
1845                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
1846                                 return 0;
1847                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1848                 } else if (!multicast &&
1849                            compare_ether_addr(sdata->dev->dev_addr,
1850                                               hdr->addr1) != 0) {
1851                         if (!(sdata->dev->flags & IFF_PROMISC))
1852                                 return 0;
1853                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1854                 } else if (!rx->sta)
1855                         rx->sta = ieee80211_ibss_add_sta(sdata, rx->skb,
1856                                                 bssid, hdr->addr2,
1857                                                 BIT(rx->status->rate_idx));
1858                 break;
1859         case NL80211_IFTYPE_MESH_POINT:
1860                 if (!multicast &&
1861                     compare_ether_addr(sdata->dev->dev_addr,
1862                                        hdr->addr1) != 0) {
1863                         if (!(sdata->dev->flags & IFF_PROMISC))
1864                                 return 0;
1865
1866                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1867                 }
1868                 break;
1869         case NL80211_IFTYPE_AP_VLAN:
1870         case NL80211_IFTYPE_AP:
1871                 if (!bssid) {
1872                         if (compare_ether_addr(sdata->dev->dev_addr,
1873                                                hdr->addr1))
1874                                 return 0;
1875                 } else if (!ieee80211_bssid_match(bssid,
1876                                         sdata->dev->dev_addr)) {
1877                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
1878                                 return 0;
1879                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
1880                 }
1881                 break;
1882         case NL80211_IFTYPE_WDS:
1883                 if (bssid || !ieee80211_is_data(hdr->frame_control))
1884                         return 0;
1885                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
1886                         return 0;
1887                 break;
1888         case NL80211_IFTYPE_MONITOR:
1889                 /* take everything */
1890                 break;
1891         case NL80211_IFTYPE_UNSPECIFIED:
1892         case __NL80211_IFTYPE_AFTER_LAST:
1893                 /* should never get here */
1894                 WARN_ON(1);
1895                 break;
1896         }
1897
1898         return 1;
1899 }
1900
1901 /*
1902  * This is the actual Rx frames handler. as it blongs to Rx path it must
1903  * be called with rcu_read_lock protection.
1904  */
1905 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
1906                                          struct sk_buff *skb,
1907                                          struct ieee80211_rx_status *status,
1908                                          struct ieee80211_rate *rate)
1909 {
1910         struct ieee80211_local *local = hw_to_local(hw);
1911         struct ieee80211_sub_if_data *sdata;
1912         struct ieee80211_hdr *hdr;
1913         struct ieee80211_rx_data rx;
1914         int prepares;
1915         struct ieee80211_sub_if_data *prev = NULL;
1916         struct sk_buff *skb_new;
1917         u8 *bssid;
1918
1919         hdr = (struct ieee80211_hdr *)skb->data;
1920         memset(&rx, 0, sizeof(rx));
1921         rx.skb = skb;
1922         rx.local = local;
1923
1924         rx.status = status;
1925         rx.rate = rate;
1926
1927         if (ieee80211_is_data(hdr->frame_control) || ieee80211_is_mgmt(hdr->frame_control))
1928                 local->dot11ReceivedFragmentCount++;
1929
1930         rx.sta = sta_info_get(local, hdr->addr2);
1931         if (rx.sta) {
1932                 rx.sdata = rx.sta->sdata;
1933                 rx.dev = rx.sta->sdata->dev;
1934         }
1935
1936         if ((status->flag & RX_FLAG_MMIC_ERROR)) {
1937                 ieee80211_rx_michael_mic_report(local->mdev, hdr, &rx);
1938                 return;
1939         }
1940
1941         if (unlikely(local->sw_scanning || local->hw_scanning))
1942                 rx.flags |= IEEE80211_RX_IN_SCAN;
1943
1944         ieee80211_parse_qos(&rx);
1945         ieee80211_verify_ip_alignment(&rx);
1946
1947         skb = rx.skb;
1948
1949         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1950                 if (!netif_running(sdata->dev))
1951                         continue;
1952
1953                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR)
1954                         continue;
1955
1956                 bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
1957                 rx.flags |= IEEE80211_RX_RA_MATCH;
1958                 prepares = prepare_for_handlers(sdata, bssid, &rx, hdr);
1959
1960                 if (!prepares)
1961                         continue;
1962
1963                 /*
1964                  * frame is destined for this interface, but if it's not
1965                  * also for the previous one we handle that after the
1966                  * loop to avoid copying the SKB once too much
1967                  */
1968
1969                 if (!prev) {
1970                         prev = sdata;
1971                         continue;
1972                 }
1973
1974                 /*
1975                  * frame was destined for the previous interface
1976                  * so invoke RX handlers for it
1977                  */
1978
1979                 skb_new = skb_copy(skb, GFP_ATOMIC);
1980                 if (!skb_new) {
1981                         if (net_ratelimit())
1982                                 printk(KERN_DEBUG "%s: failed to copy "
1983                                        "multicast frame for %s\n",
1984                                        wiphy_name(local->hw.wiphy),
1985                                        prev->dev->name);
1986                         continue;
1987                 }
1988                 ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
1989                 prev = sdata;
1990         }
1991         if (prev)
1992                 ieee80211_invoke_rx_handlers(prev, &rx, skb);
1993         else
1994                 dev_kfree_skb(skb);
1995 }
1996
1997 #define SEQ_MODULO 0x1000
1998 #define SEQ_MASK   0xfff
1999
2000 static inline int seq_less(u16 sq1, u16 sq2)
2001 {
2002         return (((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1));
2003 }
2004
2005 static inline u16 seq_inc(u16 sq)
2006 {
2007         return ((sq + 1) & SEQ_MASK);
2008 }
2009
2010 static inline u16 seq_sub(u16 sq1, u16 sq2)
2011 {
2012         return ((sq1 - sq2) & SEQ_MASK);
2013 }
2014
2015
2016 /*
2017  * As it function blongs to Rx path it must be called with
2018  * the proper rcu_read_lock protection for its flow.
2019  */
2020 u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
2021                                 struct tid_ampdu_rx *tid_agg_rx,
2022                                 struct sk_buff *skb, u16 mpdu_seq_num,
2023                                 int bar_req)
2024 {
2025         struct ieee80211_local *local = hw_to_local(hw);
2026         struct ieee80211_rx_status status;
2027         u16 head_seq_num, buf_size;
2028         int index;
2029         struct ieee80211_supported_band *sband;
2030         struct ieee80211_rate *rate;
2031
2032         buf_size = tid_agg_rx->buf_size;
2033         head_seq_num = tid_agg_rx->head_seq_num;
2034
2035         /* frame with out of date sequence number */
2036         if (seq_less(mpdu_seq_num, head_seq_num)) {
2037                 dev_kfree_skb(skb);
2038                 return 1;
2039         }
2040
2041         /* if frame sequence number exceeds our buffering window size or
2042          * block Ack Request arrived - release stored frames */
2043         if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
2044                 /* new head to the ordering buffer */
2045                 if (bar_req)
2046                         head_seq_num = mpdu_seq_num;
2047                 else
2048                         head_seq_num =
2049                                 seq_inc(seq_sub(mpdu_seq_num, buf_size));
2050                 /* release stored frames up to new head to stack */
2051                 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
2052                         index = seq_sub(tid_agg_rx->head_seq_num,
2053                                 tid_agg_rx->ssn)
2054                                 % tid_agg_rx->buf_size;
2055
2056                         if (tid_agg_rx->reorder_buf[index]) {
2057                                 /* release the reordered frames to stack */
2058                                 memcpy(&status,
2059                                         tid_agg_rx->reorder_buf[index]->cb,
2060                                         sizeof(status));
2061                                 sband = local->hw.wiphy->bands[status.band];
2062                                 rate = &sband->bitrates[status.rate_idx];
2063                                 __ieee80211_rx_handle_packet(hw,
2064                                         tid_agg_rx->reorder_buf[index],
2065                                         &status, rate);
2066                                 tid_agg_rx->stored_mpdu_num--;
2067                                 tid_agg_rx->reorder_buf[index] = NULL;
2068                         }
2069                         tid_agg_rx->head_seq_num =
2070                                 seq_inc(tid_agg_rx->head_seq_num);
2071                 }
2072                 if (bar_req)
2073                         return 1;
2074         }
2075
2076         /* now the new frame is always in the range of the reordering */
2077         /* buffer window */
2078         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
2079                                 % tid_agg_rx->buf_size;
2080         /* check if we already stored this frame */
2081         if (tid_agg_rx->reorder_buf[index]) {
2082                 dev_kfree_skb(skb);
2083                 return 1;
2084         }
2085
2086         /* if arrived mpdu is in the right order and nothing else stored */
2087         /* release it immediately */
2088         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
2089                         tid_agg_rx->stored_mpdu_num == 0) {
2090                 tid_agg_rx->head_seq_num =
2091                         seq_inc(tid_agg_rx->head_seq_num);
2092                 return 0;
2093         }
2094
2095         /* put the frame in the reordering buffer */
2096         tid_agg_rx->reorder_buf[index] = skb;
2097         tid_agg_rx->stored_mpdu_num++;
2098         /* release the buffer until next missing frame */
2099         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
2100                                                 % tid_agg_rx->buf_size;
2101         while (tid_agg_rx->reorder_buf[index]) {
2102                 /* release the reordered frame back to stack */
2103                 memcpy(&status, tid_agg_rx->reorder_buf[index]->cb,
2104                         sizeof(status));
2105                 sband = local->hw.wiphy->bands[status.band];
2106                 rate = &sband->bitrates[status.rate_idx];
2107                 __ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index],
2108                                              &status, rate);
2109                 tid_agg_rx->stored_mpdu_num--;
2110                 tid_agg_rx->reorder_buf[index] = NULL;
2111                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
2112                 index = seq_sub(tid_agg_rx->head_seq_num,
2113                         tid_agg_rx->ssn) % tid_agg_rx->buf_size;
2114         }
2115         return 1;
2116 }
2117
2118 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
2119                                      struct sk_buff *skb)
2120 {
2121         struct ieee80211_hw *hw = &local->hw;
2122         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
2123         struct sta_info *sta;
2124         struct tid_ampdu_rx *tid_agg_rx;
2125         u16 sc;
2126         u16 mpdu_seq_num;
2127         u8 ret = 0;
2128         int tid;
2129
2130         sta = sta_info_get(local, hdr->addr2);
2131         if (!sta)
2132                 return ret;
2133
2134         /* filter the QoS data rx stream according to
2135          * STA/TID and check if this STA/TID is on aggregation */
2136         if (!ieee80211_is_data_qos(hdr->frame_control))
2137                 goto end_reorder;
2138
2139         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
2140
2141         if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
2142                 goto end_reorder;
2143
2144         tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
2145
2146         /* qos null data frames are excluded */
2147         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
2148                 goto end_reorder;
2149
2150         /* new un-ordered ampdu frame - process it */
2151
2152         /* reset session timer */
2153         if (tid_agg_rx->timeout) {
2154                 unsigned long expires =
2155                         jiffies + (tid_agg_rx->timeout / 1000) * HZ;
2156                 mod_timer(&tid_agg_rx->session_timer, expires);
2157         }
2158
2159         /* if this mpdu is fragmented - terminate rx aggregation session */
2160         sc = le16_to_cpu(hdr->seq_ctrl);
2161         if (sc & IEEE80211_SCTL_FRAG) {
2162                 ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
2163                         tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
2164                 ret = 1;
2165                 goto end_reorder;
2166         }
2167
2168         /* according to mpdu sequence number deal with reordering buffer */
2169         mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
2170         ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb,
2171                                                 mpdu_seq_num, 0);
2172  end_reorder:
2173         return ret;
2174 }
2175
2176 /*
2177  * This is the receive path handler. It is called by a low level driver when an
2178  * 802.11 MPDU is received from the hardware.
2179  */
2180 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
2181                     struct ieee80211_rx_status *status)
2182 {
2183         struct ieee80211_local *local = hw_to_local(hw);
2184         struct ieee80211_rate *rate = NULL;
2185         struct ieee80211_supported_band *sband;
2186
2187         if (status->band < 0 ||
2188             status->band >= IEEE80211_NUM_BANDS) {
2189                 WARN_ON(1);
2190                 return;
2191         }
2192
2193         sband = local->hw.wiphy->bands[status->band];
2194
2195         if (!sband ||
2196             status->rate_idx < 0 ||
2197             status->rate_idx >= sband->n_bitrates) {
2198                 WARN_ON(1);
2199                 return;
2200         }
2201
2202         rate = &sband->bitrates[status->rate_idx];
2203
2204         /*
2205          * key references and virtual interfaces are protected using RCU
2206          * and this requires that we are in a read-side RCU section during
2207          * receive processing
2208          */
2209         rcu_read_lock();
2210
2211         /*
2212          * Frames with failed FCS/PLCP checksum are not returned,
2213          * all other frames are returned without radiotap header
2214          * if it was previously present.
2215          * Also, frames with less than 16 bytes are dropped.
2216          */
2217         skb = ieee80211_rx_monitor(local, skb, status, rate);
2218         if (!skb) {
2219                 rcu_read_unlock();
2220                 return;
2221         }
2222
2223         if (!ieee80211_rx_reorder_ampdu(local, skb))
2224                 __ieee80211_rx_handle_packet(hw, skb, status, rate);
2225
2226         rcu_read_unlock();
2227 }
2228 EXPORT_SYMBOL(__ieee80211_rx);
2229
2230 /* This is a version of the rx handler that can be called from hard irq
2231  * context. Post the skb on the queue and schedule the tasklet */
2232 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
2233                           struct ieee80211_rx_status *status)
2234 {
2235         struct ieee80211_local *local = hw_to_local(hw);
2236
2237         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2238
2239         skb->dev = local->mdev;
2240         /* copy status into skb->cb for use by tasklet */
2241         memcpy(skb->cb, status, sizeof(*status));
2242         skb->pkt_type = IEEE80211_RX_MSG;
2243         skb_queue_tail(&local->skb_queue, skb);
2244         tasklet_schedule(&local->tasklet);
2245 }
2246 EXPORT_SYMBOL(ieee80211_rx_irqsafe);