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 "driver-ops.h"
  23 #include "led.h"
  24 #include "mesh.h"
  25 #include "wep.h"
  26 #include "wpa.h"
  27 #include "tkip.h"
  28 #include "wme.h"
  29
  30 static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
  31                                            struct tid_ampdu_rx *tid_agg_rx,
  32                                            struct sk_buff *skb,
  33                                            struct ieee80211_rx_status *status,
  34                                            u16 mpdu_seq_num,
  35                                            int bar_req);
  36 /*
  37  * monitor mode reception
  38  *
  39  * This function cleans up the SKB, i.e. it removes all the stuff
  40  * only useful for monitoring.
  41  */
  42 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
  43                                            struct sk_buff *skb,
  44                                            int rtap_len)
  45 {
  46         skb_pull(skb, rtap_len);
  47
  48         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
  49                 if (likely(skb->len > FCS_LEN))
  50                         skb_trim(skb, skb->len - FCS_LEN);
  51                 else {
  52                         /* driver bug */
  53                         WARN_ON(1);
  54                         dev_kfree_skb(skb);
  55                         skb = NULL;
  56                 }
  57         }
  58
  59         return skb;
  60 }
  61
  62 static inline int should_drop_frame(struct ieee80211_rx_status *status,
  63                                     struct sk_buff *skb,
  64                                     int present_fcs_len,
  65                                     int radiotap_len)
  66 {
  67         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  68
  69         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
  70                 return 1;
  71         if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len))
  72                 return 1;
  73         if (ieee80211_is_ctl(hdr->frame_control) &&
  74             !ieee80211_is_pspoll(hdr->frame_control) &&
  75             !ieee80211_is_back_req(hdr->frame_control))
  76                 return 1;
  77         return 0;
  78 }
  79
  80 static int
  81 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
  82                           struct ieee80211_rx_status *status)
  83 {
  84         int len;
  85
  86         /* always present fields */
  87         len = sizeof(struct ieee80211_radiotap_header) + 9;
  88
  89         if (status->flag & RX_FLAG_TSFT)
  90                 len += 8;
  91         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
  92                 len += 1;
  93         if (local->hw.flags & IEEE80211_HW_NOISE_DBM)
  94                 len += 1;
  95
  96         if (len & 1) /* padding for RX_FLAGS if necessary */
  97                 len++;
  98
  99         /* make sure radiotap starts at a naturally aligned address */
 100         if (len % 8)
 101                 len = roundup(len, 8);
 102
 103         return len;
 104 }
 105
 106 /*
 107  * ieee80211_add_rx_radiotap_header - add radiotap header
 108  *
 109  * add a radiotap header containing all the fields which the hardware provided.
 110  */
 111 static void
 112 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
 113                                  struct sk_buff *skb,
 114                                  struct ieee80211_rx_status *status,
 115                                  struct ieee80211_rate *rate,
 116                                  int rtap_len)
 117 {
 118         struct ieee80211_radiotap_header *rthdr;
 119         unsigned char *pos;
 120
 121         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
 122         memset(rthdr, 0, rtap_len);
 123
 124         /* radiotap header, set always present flags */
 125         rthdr->it_present =
 126                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 127                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
 128                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
 129                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
 130         rthdr->it_len = cpu_to_le16(rtap_len);
 131
 132         pos = (unsigned char *)(rthdr+1);
 133
 134         /* the order of the following fields is important */
 135
 136         /* IEEE80211_RADIOTAP_TSFT */
 137         if (status->flag & RX_FLAG_TSFT) {
 138                 *(__le64 *)pos = cpu_to_le64(status->mactime);
 139                 rthdr->it_present |=
 140                         cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
 141                 pos += 8;
 142         }
 143
 144         /* IEEE80211_RADIOTAP_FLAGS */
 145         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 146                 *pos |= IEEE80211_RADIOTAP_F_FCS;
 147         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 148                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
 149         if (status->flag & RX_FLAG_SHORTPRE)
 150                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
 151         pos++;
 152
 153         /* IEEE80211_RADIOTAP_RATE */
 154         if (status->flag & RX_FLAG_HT) {
 155                 /*
 156                  * TODO: add following information into radiotap header once
 157                  * suitable fields are defined for it:
 158                  * - MCS index (status->rate_idx)
 159                  * - HT40 (status->flag & RX_FLAG_40MHZ)
 160                  * - short-GI (status->flag & RX_FLAG_SHORT_GI)
 161                  */
 162                 *pos = 0;
 163         } else {
 164                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
 165                 *pos = rate->bitrate / 5;
 166         }
 167         pos++;
 168
 169         /* IEEE80211_RADIOTAP_CHANNEL */
 170         *(__le16 *)pos = cpu_to_le16(status->freq);
 171         pos += 2;
 172         if (status->band == IEEE80211_BAND_5GHZ)
 173                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
 174                                              IEEE80211_CHAN_5GHZ);
 175         else if (rate->flags & IEEE80211_RATE_ERP_G)
 176                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
 177                                              IEEE80211_CHAN_2GHZ);
 178         else
 179                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_CCK |
 180                                              IEEE80211_CHAN_2GHZ);
 181         pos += 2;
 182
 183         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
 184         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
 185                 *pos = status->signal;
 186                 rthdr->it_present |=
 187                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
 188                 pos++;
 189         }
 190
 191         /* IEEE80211_RADIOTAP_DBM_ANTNOISE */
 192         if (local->hw.flags & IEEE80211_HW_NOISE_DBM) {
 193                 *pos = status->noise;
 194                 rthdr->it_present |=
 195                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE);
 196                 pos++;
 197         }
 198
 199         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
 200
 201         /* IEEE80211_RADIOTAP_ANTENNA */
 202         *pos = status->antenna;
 203         pos++;
 204
 205         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
 206
 207         /* IEEE80211_RADIOTAP_RX_FLAGS */
 208         /* ensure 2 byte alignment for the 2 byte field as required */
 209         if ((pos - (unsigned char *)rthdr) & 1)
 210                 pos++;
 211         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
 212                 *(__le16 *)pos |= cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADPLCP);
 213         pos += 2;
 214 }
 215
 216 /*
 217  * This function copies a received frame to all monitor interfaces and
 218  * returns a cleaned-up SKB that no longer includes the FCS nor the
 219  * radiotap header the driver might have added.
 220  */
 221 static struct sk_buff *
 222 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
 223                      struct ieee80211_rx_status *status,
 224                      struct ieee80211_rate *rate)
 225 {
 226         struct ieee80211_sub_if_data *sdata;
 227         int needed_headroom = 0;
 228         struct sk_buff *skb, *skb2;
 229         struct net_device *prev_dev = NULL;
 230         int present_fcs_len = 0;
 231         int rtap_len = 0;
 232
 233         /*
 234          * First, we may need to make a copy of the skb because
 235          *  (1) we need to modify it for radiotap (if not present), and
 236          *  (2) the other RX handlers will modify the skb we got.
 237          *
 238          * We don't need to, of course, if we aren't going to return
 239          * the SKB because it has a bad FCS/PLCP checksum.
 240          */
 241         if (status->flag & RX_FLAG_RADIOTAP)
 242                 rtap_len = ieee80211_get_radiotap_len(origskb->data);
 243         else
 244                 /* room for the radiotap header based on driver features */
 245                 needed_headroom = ieee80211_rx_radiotap_len(local, status);
 246
 247         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 248                 present_fcs_len = FCS_LEN;
 249
 250         if (!local->monitors) {
 251                 if (should_drop_frame(status, origskb, present_fcs_len,
 252                                       rtap_len)) {
 253                         dev_kfree_skb(origskb);
 254                         return NULL;
 255                 }
 256
 257                 return remove_monitor_info(local, origskb, rtap_len);
 258         }
 259
 260         if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) {
 261                 /* only need to expand headroom if necessary */
 262                 skb = origskb;
 263                 origskb = NULL;
 264
 265                 /*
 266                  * This shouldn't trigger often because most devices have an
 267                  * RX header they pull before we get here, and that should
 268                  * be big enough for our radiotap information. We should
 269                  * probably export the length to drivers so that we can have
 270                  * them allocate enough headroom to start with.
 271                  */
 272                 if (skb_headroom(skb) < needed_headroom &&
 273                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
 274                         dev_kfree_skb(skb);
 275                         return NULL;
 276                 }
 277         } else {
 278                 /*
 279                  * Need to make a copy and possibly remove radiotap header
 280                  * and FCS from the original.
 281                  */
 282                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
 283
 284                 origskb = remove_monitor_info(local, origskb, rtap_len);
 285
 286                 if (!skb)
 287                         return origskb;
 288         }
 289
 290         /* if necessary, prepend radiotap information */
 291         if (!(status->flag & RX_FLAG_RADIOTAP))
 292                 ieee80211_add_rx_radiotap_header(local, skb, status, rate,
 293                                                  needed_headroom);
 294
 295         skb_reset_mac_header(skb);
 296         skb->ip_summed = CHECKSUM_UNNECESSARY;
 297         skb->pkt_type = PACKET_OTHERHOST;
 298         skb->protocol = htons(ETH_P_802_2);
 299
 300         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 301                 if (!netif_running(sdata->dev))
 302                         continue;
 303
 304                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
 305                         continue;
 306
 307                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
 308                         continue;
 309
 310                 if (prev_dev) {
 311                         skb2 = skb_clone(skb, GFP_ATOMIC);
 312                         if (skb2) {
 313                                 skb2->dev = prev_dev;
 314                                 netif_rx(skb2);
 315                         }
 316                 }
 317
 318                 prev_dev = sdata->dev;
 319                 sdata->dev->stats.rx_packets++;
 320                 sdata->dev->stats.rx_bytes += skb->len;
 321         }
 322
 323         if (prev_dev) {
 324                 skb->dev = prev_dev;
 325                 netif_rx(skb);
 326         } else
 327                 dev_kfree_skb(skb);
 328
 329         return origskb;
 330 }
 331
 332
 333 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
 334 {
 335         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 336         int tid;
 337
 338         /* does the frame have a qos control field? */
 339         if (ieee80211_is_data_qos(hdr->frame_control)) {
 340                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 341                 /* frame has qos control */
 342                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
 343                 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
 344                         rx->flags |= IEEE80211_RX_AMSDU;
 345                 else
 346                         rx->flags &= ~IEEE80211_RX_AMSDU;
 347         } else {
 348                 /*
 349                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
 350                  *
 351                  *      Sequence numbers for management frames, QoS data
 352                  *      frames with a broadcast/multicast address in the
 353                  *      Address 1 field, and all non-QoS data frames sent
 354                  *      by QoS STAs are assigned using an additional single
 355                  *      modulo-4096 counter, [...]
 356                  *
 357                  * We also use that counter for non-QoS STAs.
 358                  */
 359                 tid = NUM_RX_DATA_QUEUES - 1;
 360         }
 361
 362         rx->queue = tid;
 363         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 364          * For now, set skb->priority to 0 for other cases. */
 365         rx->skb->priority = (tid > 7) ? 0 : tid;
 366 }
 367
 368 /**
 369  * DOC: Packet alignment
 370  *
 371  * Drivers always need to pass packets that are aligned to two-byte boundaries
 372  * to the stack.
 373  *
 374  * Additionally, should, if possible, align the payload data in a way that
 375  * guarantees that the contained IP header is aligned to a four-byte
 376  * boundary. In the case of regular frames, this simply means aligning the
 377  * payload to a four-byte boundary (because either the IP header is directly
 378  * contained, or IV/RFC1042 headers that have a length divisible by four are
 379  * in front of it).
 380  *
 381  * With A-MSDU frames, however, the payload data address must yield two modulo
 382  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
 383  * push the IP header further back to a multiple of four again. Thankfully, the
 384  * specs were sane enough this time around to require padding each A-MSDU
 385  * subframe to a length that is a multiple of four.
 386  *
 387  * Padding like Atheros hardware adds which is inbetween the 802.11 header and
 388  * the payload is not supported, the driver is required to move the 802.11
 389  * header to be directly in front of the payload in that case.
 390  */
 391 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
 392 {
 393         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 394         int hdrlen;
 395
 396 #ifndef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
 397         return;
 398 #endif
 399
 400         if (WARN_ONCE((unsigned long)rx->skb->data & 1,
 401                       "unaligned packet at 0x%p\n", rx->skb->data))
 402                 return;
 403
 404         if (!ieee80211_is_data_present(hdr->frame_control))
 405                 return;
 406
 407         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 408         if (rx->flags & IEEE80211_RX_AMSDU)
 409                 hdrlen += ETH_HLEN;
 410         WARN_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3,
 411                   "unaligned IP payload at 0x%p\n", rx->skb->data + hdrlen);
 412 }
 413
 414
 415 /* rx handlers */
 416
 417 static ieee80211_rx_result debug_noinline
 418 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
 419 {
 420         struct ieee80211_local *local = rx->local;
 421         struct sk_buff *skb = rx->skb;
 422
 423         if (unlikely(local->hw_scanning))
 424                 return ieee80211_scan_rx(rx->sdata, skb, rx->status);
 425
 426         if (unlikely(local->sw_scanning)) {
 427                 /* drop all the other packets during a software scan anyway */
 428                 if (ieee80211_scan_rx(rx->sdata, skb, rx->status)
 429                     != RX_QUEUED)
 430                         dev_kfree_skb(skb);
 431                 return RX_QUEUED;
 432         }
 433
 434         if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
 435                 /* scanning finished during invoking of handlers */
 436                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
 437                 return RX_DROP_UNUSABLE;
 438         }
 439
 440         return RX_CONTINUE;
 441 }
 442
 443
 444 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
 445 {
 446         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 447
 448         if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
 449                 return 0;
 450
 451         return ieee80211_is_robust_mgmt_frame(hdr);
 452 }
 453
 454
 455 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
 456 {
 457         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 458
 459         if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
 460                 return 0;
 461
 462         return ieee80211_is_robust_mgmt_frame(hdr);
 463 }
 464
 465
 466 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
 467 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
 468 {
 469         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
 470         struct ieee80211_mmie *mmie;
 471
 472         if (skb->len < 24 + sizeof(*mmie) ||
 473             !is_multicast_ether_addr(hdr->da))
 474                 return -1;
 475
 476         if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
 477                 return -1; /* not a robust management frame */
 478
 479         mmie = (struct ieee80211_mmie *)
 480                 (skb->data + skb->len - sizeof(*mmie));
 481         if (mmie->element_id != WLAN_EID_MMIE ||
 482             mmie->length != sizeof(*mmie) - 2)
 483                 return -1;
 484
 485         return le16_to_cpu(mmie->key_id);
 486 }
 487
 488
 489 static ieee80211_rx_result
 490 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
 491 {
 492         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 493         unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
 494
 495         if (ieee80211_is_data(hdr->frame_control)) {
 496                 if (!ieee80211_has_a4(hdr->frame_control))
 497                         return RX_DROP_MONITOR;
 498                 if (memcmp(hdr->addr4, rx->dev->dev_addr, ETH_ALEN) == 0)
 499                         return RX_DROP_MONITOR;
 500         }
 501
 502         /* If there is not an established peer link and this is not a peer link
 503          * establisment frame, beacon or probe, drop the frame.
 504          */
 505
 506         if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
 507                 struct ieee80211_mgmt *mgmt;
 508
 509                 if (!ieee80211_is_mgmt(hdr->frame_control))
 510                         return RX_DROP_MONITOR;
 511
 512                 if (ieee80211_is_action(hdr->frame_control)) {
 513                         mgmt = (struct ieee80211_mgmt *)hdr;
 514                         if (mgmt->u.action.category != PLINK_CATEGORY)
 515                                 return RX_DROP_MONITOR;
 516                         return RX_CONTINUE;
 517                 }
 518
 519                 if (ieee80211_is_probe_req(hdr->frame_control) ||
 520                     ieee80211_is_probe_resp(hdr->frame_control) ||
 521                     ieee80211_is_beacon(hdr->frame_control))
 522                         return RX_CONTINUE;
 523
 524                 return RX_DROP_MONITOR;
 525
 526         }
 527
 528 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
 529
 530         if (ieee80211_is_data(hdr->frame_control) &&
 531             is_multicast_ether_addr(hdr->addr1) &&
 532             mesh_rmc_check(hdr->addr4, msh_h_get(hdr, hdrlen), rx->sdata))
 533                 return RX_DROP_MONITOR;
 534 #undef msh_h_get
 535
 536         return RX_CONTINUE;
 537 }
 538
 539
 540 static ieee80211_rx_result debug_noinline
 541 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
 542 {
 543         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 544
 545         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 546         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 547                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
 548                              rx->sta->last_seq_ctrl[rx->queue] ==
 549                              hdr->seq_ctrl)) {
 550                         if (rx->flags & IEEE80211_RX_RA_MATCH) {
 551                                 rx->local->dot11FrameDuplicateCount++;
 552                                 rx->sta->num_duplicates++;
 553                         }
 554                         return RX_DROP_MONITOR;
 555                 } else
 556                         rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
 557         }
 558
 559         if (unlikely(rx->skb->len < 16)) {
 560                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 561                 return RX_DROP_MONITOR;
 562         }
 563
 564         /* Drop disallowed frame classes based on STA auth/assoc state;
 565          * IEEE 802.11, Chap 5.5.
 566          *
 567          * mac80211 filters only based on association state, i.e. it drops
 568          * Class 3 frames from not associated stations. hostapd sends
 569          * deauth/disassoc frames when needed. In addition, hostapd is
 570          * responsible for filtering on both auth and assoc states.
 571          */
 572
 573         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
 574                 return ieee80211_rx_mesh_check(rx);
 575
 576         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
 577                       ieee80211_is_pspoll(hdr->frame_control)) &&
 578                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
 579                      (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
 580                 if ((!ieee80211_has_fromds(hdr->frame_control) &&
 581                      !ieee80211_has_tods(hdr->frame_control) &&
 582                      ieee80211_is_data(hdr->frame_control)) ||
 583                     !(rx->flags & IEEE80211_RX_RA_MATCH)) {
 584                         /* Drop IBSS frames and frames for other hosts
 585                          * silently. */
 586                         return RX_DROP_MONITOR;
 587                 }
 588
 589                 return RX_DROP_MONITOR;
 590         }
 591
 592         return RX_CONTINUE;
 593 }
 594
 595
 596 static ieee80211_rx_result debug_noinline
 597 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
 598 {
 599         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 600         int keyidx;
 601         int hdrlen;
 602         ieee80211_rx_result result = RX_DROP_UNUSABLE;
 603         struct ieee80211_key *stakey = NULL;
 604         int mmie_keyidx = -1;
 605
 606         /*
 607          * Key selection 101
 608          *
 609          * There are four types of keys:
 610          *  - GTK (group keys)
 611          *  - IGTK (group keys for management frames)
 612          *  - PTK (pairwise keys)
 613          *  - STK (station-to-station pairwise keys)
 614          *
 615          * When selecting a key, we have to distinguish between multicast
 616          * (including broadcast) and unicast frames, the latter can only
 617          * use PTKs and STKs while the former always use GTKs and IGTKs.
 618          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
 619          * unicast frames can also use key indices like GTKs. Hence, if we
 620          * don't have a PTK/STK we check the key index for a WEP key.
 621          *
 622          * Note that in a regular BSS, multicast frames are sent by the
 623          * AP only, associated stations unicast the frame to the AP first
 624          * which then multicasts it on their behalf.
 625          *
 626          * There is also a slight problem in IBSS mode: GTKs are negotiated
 627          * with each station, that is something we don't currently handle.
 628          * The spec seems to expect that one negotiates the same key with
 629          * every station but there's no such requirement; VLANs could be
 630          * possible.
 631          */
 632
 633         if (!ieee80211_has_protected(hdr->frame_control)) {
 634                 if (!ieee80211_is_mgmt(hdr->frame_control) ||
 635                     rx->sta == NULL || !test_sta_flags(rx->sta, WLAN_STA_MFP))
 636                         return RX_CONTINUE;
 637                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
 638                 if (mmie_keyidx < 0)
 639                         return RX_CONTINUE;
 640         }
 641
 642         /*
 643          * No point in finding a key and decrypting if the frame is neither
 644          * addressed to us nor a multicast frame.
 645          */
 646         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
 647                 return RX_CONTINUE;
 648
 649         if (rx->sta)
 650                 stakey = rcu_dereference(rx->sta->key);
 651
 652         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
 653                 rx->key = stakey;
 654         } else if (mmie_keyidx >= 0) {
 655                 /* Broadcast/multicast robust management frame / BIP */
 656                 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
 657                     (rx->status->flag & RX_FLAG_IV_STRIPPED))
 658                         return RX_CONTINUE;
 659
 660                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
 661                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
 662                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
 663                 rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
 664         } else {
 665                 /*
 666                  * The device doesn't give us the IV so we won't be
 667                  * able to look up the key. That's ok though, we
 668                  * don't need to decrypt the frame, we just won't
 669                  * be able to keep statistics accurate.
 670                  * Except for key threshold notifications, should
 671                  * we somehow allow the driver to tell us which key
 672                  * the hardware used if this flag is set?
 673                  */
 674                 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
 675                     (rx->status->flag & RX_FLAG_IV_STRIPPED))
 676                         return RX_CONTINUE;
 677
 678                 hdrlen = ieee80211_hdrlen(hdr->frame_control);
 679
 680                 if (rx->skb->len < 8 + hdrlen)
 681                         return RX_DROP_UNUSABLE; /* TODO: count this? */
 682
 683                 /*
 684                  * no need to call ieee80211_wep_get_keyidx,
 685                  * it verifies a bunch of things we've done already
 686                  */
 687                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
 688
 689                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
 690
 691                 /*
 692                  * RSNA-protected unicast frames should always be sent with
 693                  * pairwise or station-to-station keys, but for WEP we allow
 694                  * using a key index as well.
 695                  */
 696                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
 697                     !is_multicast_ether_addr(hdr->addr1))
 698                         rx->key = NULL;
 699         }
 700
 701         if (rx->key) {
 702                 rx->key->tx_rx_count++;
 703                 /* TODO: add threshold stuff again */
 704         } else {
 705                 return RX_DROP_MONITOR;
 706         }
 707
 708         /* Check for weak IVs if possible */
 709         if (rx->sta && rx->key->conf.alg == ALG_WEP &&
 710             ieee80211_is_data(hdr->frame_control) &&
 711             (!(rx->status->flag & RX_FLAG_IV_STRIPPED) ||
 712              !(rx->status->flag & RX_FLAG_DECRYPTED)) &&
 713             ieee80211_wep_is_weak_iv(rx->skb, rx->key))
 714                 rx->sta->wep_weak_iv_count++;
 715
 716         switch (rx->key->conf.alg) {
 717         case ALG_WEP:
 718                 result = ieee80211_crypto_wep_decrypt(rx);
 719                 break;
 720         case ALG_TKIP:
 721                 result = ieee80211_crypto_tkip_decrypt(rx);
 722                 break;
 723         case ALG_CCMP:
 724                 result = ieee80211_crypto_ccmp_decrypt(rx);
 725                 break;
 726         case ALG_AES_CMAC:
 727                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
 728                 break;
 729         }
 730
 731         /* either the frame has been decrypted or will be dropped */
 732         rx->status->flag |= RX_FLAG_DECRYPTED;
 733
 734         return result;
 735 }
 736
 737 static ieee80211_rx_result debug_noinline
 738 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
 739 {
 740         struct ieee80211_local *local;
 741         struct ieee80211_hdr *hdr;
 742         struct sk_buff *skb;
 743
 744         local = rx->local;
 745         skb = rx->skb;
 746         hdr = (struct ieee80211_hdr *) skb->data;
 747
 748         if (!local->pspolling)
 749                 return RX_CONTINUE;
 750
 751         if (!ieee80211_has_fromds(hdr->frame_control))
 752                 /* this is not from AP */
 753                 return RX_CONTINUE;
 754
 755         if (!ieee80211_is_data(hdr->frame_control))
 756                 return RX_CONTINUE;
 757
 758         if (!ieee80211_has_moredata(hdr->frame_control)) {
 759                 /* AP has no more frames buffered for us */
 760                 local->pspolling = false;
 761                 return RX_CONTINUE;
 762         }
 763
 764         /* more data bit is set, let's request a new frame from the AP */
 765         ieee80211_send_pspoll(local, rx->sdata);
 766
 767         return RX_CONTINUE;
 768 }
 769
 770 static void ap_sta_ps_start(struct sta_info *sta)
 771 {
 772         struct ieee80211_sub_if_data *sdata = sta->sdata;
 773         struct ieee80211_local *local = sdata->local;
 774
 775         atomic_inc(&sdata->bss->num_sta_ps);
 776         set_and_clear_sta_flags(sta, WLAN_STA_PS, WLAN_STA_PSPOLL);
 777         drv_sta_notify(local, &sdata->vif, STA_NOTIFY_SLEEP, &sta->sta);
 778 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 779         printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
 780                sdata->dev->name, sta->sta.addr, sta->sta.aid);
 781 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 782 }
 783
 784 static int ap_sta_ps_end(struct sta_info *sta)
 785 {
 786         struct ieee80211_sub_if_data *sdata = sta->sdata;
 787         struct ieee80211_local *local = sdata->local;
 788         struct sk_buff *skb;
 789         int sent = 0;
 790
 791         atomic_dec(&sdata->bss->num_sta_ps);
 792
 793         clear_sta_flags(sta, WLAN_STA_PS | WLAN_STA_PSPOLL);
 794         drv_sta_notify(local, &sdata->vif, STA_NOTIFY_AWAKE, &sta->sta);
 795
 796         if (!skb_queue_empty(&sta->ps_tx_buf))
 797                 sta_info_clear_tim_bit(sta);
 798
 799 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 800         printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
 801                sdata->dev->name, sta->sta.addr, sta->sta.aid);
 802 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 803
 804         /* Send all buffered frames to the station */
 805         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
 806                 sent++;
 807                 skb->requeue = 1;
 808                 dev_queue_xmit(skb);
 809         }
 810         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
 811                 local->total_ps_buffered--;
 812                 sent++;
 813 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 814                 printk(KERN_DEBUG "%s: STA %pM aid %d send PS frame "
 815                        "since STA not sleeping anymore\n", sdata->dev->name,
 816                        sta->sta.addr, sta->sta.aid);
 817 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 818                 skb->requeue = 1;
 819                 dev_queue_xmit(skb);
 820         }
 821
 822         return sent;
 823 }
 824
 825 static ieee80211_rx_result debug_noinline
 826 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
 827 {
 828         struct sta_info *sta = rx->sta;
 829         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 830
 831         if (!sta)
 832                 return RX_CONTINUE;
 833
 834         /* Update last_rx only for IBSS packets which are for the current
 835          * BSSID to avoid keeping the current IBSS network alive in cases where
 836          * other STAs are using different BSSID. */
 837         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
 838                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
 839                                                 NL80211_IFTYPE_ADHOC);
 840                 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0)
 841                         sta->last_rx = jiffies;
 842         } else
 843         if (!is_multicast_ether_addr(hdr->addr1) ||
 844             rx->sdata->vif.type == NL80211_IFTYPE_STATION) {
 845                 /* Update last_rx only for unicast frames in order to prevent
 846                  * the Probe Request frames (the only broadcast frames from a
 847                  * STA in infrastructure mode) from keeping a connection alive.
 848                  * Mesh beacons will update last_rx when if they are found to
 849                  * match the current local configuration when processed.
 850                  */
 851                 if (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
 852                     ieee80211_is_beacon(hdr->frame_control)) {
 853                         rx->sdata->u.mgd.last_beacon = jiffies;
 854                 } else
 855                         sta->last_rx = jiffies;
 856         }
 857
 858         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
 859                 return RX_CONTINUE;
 860
 861         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
 862                 ieee80211_sta_rx_notify(rx->sdata, hdr);
 863
 864         sta->rx_fragments++;
 865         sta->rx_bytes += rx->skb->len;
 866         sta->last_signal = rx->status->signal;
 867         sta->last_qual = rx->status->qual;
 868         sta->last_noise = rx->status->noise;
 869
 870         /*
 871          * Change STA power saving mode only at the end of a frame
 872          * exchange sequence.
 873          */
 874         if (!ieee80211_has_morefrags(hdr->frame_control) &&
 875             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
 876              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
 877                 if (test_sta_flags(sta, WLAN_STA_PS)) {
 878                         /*
 879                          * Ignore doze->wake transitions that are
 880                          * indicated by non-data frames, the standard
 881                          * is unclear here, but for example going to
 882                          * PS mode and then scanning would cause a
 883                          * doze->wake transition for the probe request,
 884                          * and that is clearly undesirable.
 885                          */
 886                         if (ieee80211_is_data(hdr->frame_control) &&
 887                             !ieee80211_has_pm(hdr->frame_control))
 888                                 rx->sent_ps_buffered += ap_sta_ps_end(sta);
 889                 } else {
 890                         if (ieee80211_has_pm(hdr->frame_control))
 891                                 ap_sta_ps_start(sta);
 892                 }
 893         }
 894
 895         /* Drop data::nullfunc frames silently, since they are used only to
 896          * control station power saving mode. */
 897         if (ieee80211_is_nullfunc(hdr->frame_control)) {
 898                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
 899                 /* Update counter and free packet here to avoid counting this
 900                  * as a dropped packed. */
 901                 sta->rx_packets++;
 902                 dev_kfree_skb(rx->skb);
 903                 return RX_QUEUED;
 904         }
 905
 906         return RX_CONTINUE;
 907 } /* ieee80211_rx_h_sta_process */
 908
 909 static inline struct ieee80211_fragment_entry *
 910 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
 911                          unsigned int frag, unsigned int seq, int rx_queue,
 912                          struct sk_buff **skb)
 913 {
 914         struct ieee80211_fragment_entry *entry;
 915         int idx;
 916
 917         idx = sdata->fragment_next;
 918         entry = &sdata->fragments[sdata->fragment_next++];
 919         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
 920                 sdata->fragment_next = 0;
 921
 922         if (!skb_queue_empty(&entry->skb_list)) {
 923 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 924                 struct ieee80211_hdr *hdr =
 925                         (struct ieee80211_hdr *) entry->skb_list.next->data;
 926                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
 927                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
 928                        "addr1=%pM addr2=%pM\n",
 929                        sdata->dev->name, idx,
 930                        jiffies - entry->first_frag_time, entry->seq,
 931                        entry->last_frag, hdr->addr1, hdr->addr2);
 932 #endif
 933                 __skb_queue_purge(&entry->skb_list);
 934         }
 935
 936         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
 937         *skb = NULL;
 938         entry->first_frag_time = jiffies;
 939         entry->seq = seq;
 940         entry->rx_queue = rx_queue;
 941         entry->last_frag = frag;
 942         entry->ccmp = 0;
 943         entry->extra_len = 0;
 944
 945         return entry;
 946 }
 947
 948 static inline struct ieee80211_fragment_entry *
 949 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
 950                           unsigned int frag, unsigned int seq,
 951                           int rx_queue, struct ieee80211_hdr *hdr)
 952 {
 953         struct ieee80211_fragment_entry *entry;
 954         int i, idx;
 955
 956         idx = sdata->fragment_next;
 957         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
 958                 struct ieee80211_hdr *f_hdr;
 959
 960                 idx--;
 961                 if (idx < 0)
 962                         idx = IEEE80211_FRAGMENT_MAX - 1;
 963
 964                 entry = &sdata->fragments[idx];
 965                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
 966                     entry->rx_queue != rx_queue ||
 967                     entry->last_frag + 1 != frag)
 968                         continue;
 969
 970                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
 971
 972                 /*
 973                  * Check ftype and addresses are equal, else check next fragment
 974                  */
 975                 if (((hdr->frame_control ^ f_hdr->frame_control) &
 976                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
 977                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
 978                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
 979                         continue;
 980
 981                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
 982                         __skb_queue_purge(&entry->skb_list);
 983                         continue;
 984                 }
 985                 return entry;
 986         }
 987
 988         return NULL;
 989 }
 990
 991 static ieee80211_rx_result debug_noinline
 992 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
 993 {
 994         struct ieee80211_hdr *hdr;
 995         u16 sc;
 996         __le16 fc;
 997         unsigned int frag, seq;
 998         struct ieee80211_fragment_entry *entry;
 999         struct sk_buff *skb;
1000
1001         hdr = (struct ieee80211_hdr *)rx->skb->data;
1002         fc = hdr->frame_control;
1003         sc = le16_to_cpu(hdr->seq_ctrl);
1004         frag = sc & IEEE80211_SCTL_FRAG;
1005
1006         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1007                    (rx->skb)->len < 24 ||
1008                    is_multicast_ether_addr(hdr->addr1))) {
1009                 /* not fragmented */
1010                 goto out;
1011         }
1012         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1013
1014         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1015
1016         if (frag == 0) {
1017                 /* This is the first fragment of a new frame. */
1018                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1019                                                  rx->queue, &(rx->skb));
1020                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
1021                     ieee80211_has_protected(fc)) {
1022                         /* Store CCMP PN so that we can verify that the next
1023                          * fragment has a sequential PN value. */
1024                         entry->ccmp = 1;
1025                         memcpy(entry->last_pn,
1026                                rx->key->u.ccmp.rx_pn[rx->queue],
1027                                CCMP_PN_LEN);
1028                 }
1029                 return RX_QUEUED;
1030         }
1031
1032         /* This is a fragment for a frame that should already be pending in
1033          * fragment cache. Add this fragment to the end of the pending entry.
1034          */
1035         entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
1036         if (!entry) {
1037                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1038                 return RX_DROP_MONITOR;
1039         }
1040
1041         /* Verify that MPDUs within one MSDU have sequential PN values.
1042          * (IEEE 802.11i, 8.3.3.4.5) */
1043         if (entry->ccmp) {
1044                 int i;
1045                 u8 pn[CCMP_PN_LEN], *rpn;
1046                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
1047                         return RX_DROP_UNUSABLE;
1048                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1049                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1050                         pn[i]++;
1051                         if (pn[i])
1052                                 break;
1053                 }
1054                 rpn = rx->key->u.ccmp.rx_pn[rx->queue];
1055                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1056                         return RX_DROP_UNUSABLE;
1057                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1058         }
1059
1060         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1061         __skb_queue_tail(&entry->skb_list, rx->skb);
1062         entry->last_frag = frag;
1063         entry->extra_len += rx->skb->len;
1064         if (ieee80211_has_morefrags(fc)) {
1065                 rx->skb = NULL;
1066                 return RX_QUEUED;
1067         }
1068
1069         rx->skb = __skb_dequeue(&entry->skb_list);
1070         if (skb_tailroom(rx->skb) < entry->extra_len) {
1071                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1072                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1073                                               GFP_ATOMIC))) {
1074                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1075                         __skb_queue_purge(&entry->skb_list);
1076                         return RX_DROP_UNUSABLE;
1077                 }
1078         }
1079         while ((skb = __skb_dequeue(&entry->skb_list))) {
1080                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1081                 dev_kfree_skb(skb);
1082         }
1083
1084         /* Complete frame has been reassembled - process it now */
1085         rx->flags |= IEEE80211_RX_FRAGMENTED;
1086
1087  out:
1088         if (rx->sta)
1089                 rx->sta->rx_packets++;
1090         if (is_multicast_ether_addr(hdr->addr1))
1091                 rx->local->dot11MulticastReceivedFrameCount++;
1092         else
1093                 ieee80211_led_rx(rx->local);
1094         return RX_CONTINUE;
1095 }
1096
1097 static ieee80211_rx_result debug_noinline
1098 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
1099 {
1100         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1101         struct sk_buff *skb;
1102         int no_pending_pkts;
1103         __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
1104
1105         if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
1106                    !(rx->flags & IEEE80211_RX_RA_MATCH)))
1107                 return RX_CONTINUE;
1108
1109         if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1110             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1111                 return RX_DROP_UNUSABLE;
1112
1113         skb = skb_dequeue(&rx->sta->tx_filtered);
1114         if (!skb) {
1115                 skb = skb_dequeue(&rx->sta->ps_tx_buf);
1116                 if (skb)
1117                         rx->local->total_ps_buffered--;
1118         }
1119         no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
1120                 skb_queue_empty(&rx->sta->ps_tx_buf);
1121
1122         if (skb) {
1123                 struct ieee80211_hdr *hdr =
1124                         (struct ieee80211_hdr *) skb->data;
1125
1126                 /*
1127                  * Tell TX path to send one frame even though the STA may
1128                  * still remain is PS mode after this frame exchange.
1129                  */
1130                 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1131
1132 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1133                 printk(KERN_DEBUG "STA %pM aid %d: PS Poll (entries after %d)\n",
1134                        rx->sta->sta.addr, rx->sta->sta.aid,
1135                        skb_queue_len(&rx->sta->ps_tx_buf));
1136 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1137
1138                 /* Use MoreData flag to indicate whether there are more
1139                  * buffered frames for this STA */
1140                 if (no_pending_pkts)
1141                         hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
1142                 else
1143                         hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1144
1145                 dev_queue_xmit(skb);
1146
1147                 if (no_pending_pkts)
1148                         sta_info_clear_tim_bit(rx->sta);
1149 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1150         } else if (!rx->sent_ps_buffered) {
1151                 /*
1152                  * FIXME: This can be the result of a race condition between
1153                  *        us expiring a frame and the station polling for it.
1154                  *        Should we send it a null-func frame indicating we
1155                  *        have nothing buffered for it?
1156                  */
1157                 printk(KERN_DEBUG "%s: STA %pM sent PS Poll even "
1158                        "though there are no buffered frames for it\n",
1159                        rx->dev->name, rx->sta->sta.addr);
1160 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1161         }
1162
1163         /* Free PS Poll skb here instead of returning RX_DROP that would
1164          * count as an dropped frame. */
1165         dev_kfree_skb(rx->skb);
1166
1167         return RX_QUEUED;
1168 }
1169
1170 static ieee80211_rx_result debug_noinline
1171 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1172 {
1173         u8 *data = rx->skb->data;
1174         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1175
1176         if (!ieee80211_is_data_qos(hdr->frame_control))
1177                 return RX_CONTINUE;
1178
1179         /* remove the qos control field, update frame type and meta-data */
1180         memmove(data + IEEE80211_QOS_CTL_LEN, data,
1181                 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1182         hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1183         /* change frame type to non QOS */
1184         hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1185
1186         return RX_CONTINUE;
1187 }
1188
1189 static int
1190 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1191 {
1192         if (unlikely(!rx->sta ||
1193             !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1194                 return -EACCES;
1195
1196         return 0;
1197 }
1198
1199 static int
1200 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1201 {
1202         /*
1203          * Pass through unencrypted frames if the hardware has
1204          * decrypted them already.
1205          */
1206         if (rx->status->flag & RX_FLAG_DECRYPTED)
1207                 return 0;
1208
1209         /* Drop unencrypted frames if key is set. */
1210         if (unlikely(!ieee80211_has_protected(fc) &&
1211                      !ieee80211_is_nullfunc(fc) &&
1212                      (!ieee80211_is_mgmt(fc) ||
1213                       (ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1214                        rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP))) &&
1215                      (rx->key || rx->sdata->drop_unencrypted)))
1216                 return -EACCES;
1217         /* BIP does not use Protected field, so need to check MMIE */
1218         if (unlikely(rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP) &&
1219                      ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1220                      ieee80211_get_mmie_keyidx(rx->skb) < 0 &&
1221                      (rx->key || rx->sdata->drop_unencrypted)))
1222                 return -EACCES;
1223
1224         return 0;
1225 }
1226
1227 static int
1228 ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1229 {
1230         struct net_device *dev = rx->dev;
1231         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
1232         u16 hdrlen, ethertype;
1233         u8 *payload;
1234         u8 dst[ETH_ALEN];
1235         u8 src[ETH_ALEN] __aligned(2);
1236         struct sk_buff *skb = rx->skb;
1237         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1238
1239         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1240                 return -1;
1241
1242         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1243
1244         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
1245          * header
1246          * IEEE 802.11 address fields:
1247          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
1248          *   0     0   DA    SA    BSSID n/a
1249          *   0     1   DA    BSSID SA    n/a
1250          *   1     0   BSSID SA    DA    n/a
1251          *   1     1   RA    TA    DA    SA
1252          */
1253         memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
1254         memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);
1255
1256         switch (hdr->frame_control &
1257                 cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
1258         case cpu_to_le16(IEEE80211_FCTL_TODS):
1259                 if (unlikely(sdata->vif.type != NL80211_IFTYPE_AP &&
1260                              sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1261                         return -1;
1262                 break;
1263         case cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
1264                 if (unlikely(sdata->vif.type != NL80211_IFTYPE_WDS &&
1265                              sdata->vif.type != NL80211_IFTYPE_MESH_POINT))
1266                         return -1;
1267                 if (ieee80211_vif_is_mesh(&sdata->vif)) {
1268                         struct ieee80211s_hdr *meshdr = (struct ieee80211s_hdr *)
1269                                 (skb->data + hdrlen);
1270                         hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
1271                         if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
1272                                 memcpy(dst, meshdr->eaddr1, ETH_ALEN);
1273                                 memcpy(src, meshdr->eaddr2, ETH_ALEN);
1274                         }
1275                 }
1276                 break;
1277         case cpu_to_le16(IEEE80211_FCTL_FROMDS):
1278                 if (sdata->vif.type != NL80211_IFTYPE_STATION ||
1279                     (is_multicast_ether_addr(dst) &&
1280                      !compare_ether_addr(src, dev->dev_addr)))
1281                         return -1;
1282                 break;
1283         case cpu_to_le16(0):
1284                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1285                         return -1;
1286                 break;
1287         }
1288
1289         if (unlikely(skb->len - hdrlen < 8))
1290                 return -1;
1291
1292         payload = skb->data + hdrlen;
1293         ethertype = (payload[6] << 8) | payload[7];
1294
1295         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1296                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1297                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1298                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1299                  * replace EtherType */
1300                 skb_pull(skb, hdrlen + 6);
1301                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1302                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1303         } else {
1304                 struct ethhdr *ehdr;
1305                 __be16 len;
1306
1307                 skb_pull(skb, hdrlen);
1308                 len = htons(skb->len);
1309                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1310                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1311                 memcpy(ehdr->h_source, src, ETH_ALEN);
1312                 ehdr->h_proto = len;
1313         }
1314         return 0;
1315 }
1316
1317 /*
1318  * requires that rx->skb is a frame with ethernet header
1319  */
1320 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1321 {
1322         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1323                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1324         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1325
1326         /*
1327          * Allow EAPOL frames to us/the PAE group address regardless
1328          * of whether the frame was encrypted or not.
1329          */
1330         if (ehdr->h_proto == htons(ETH_P_PAE) &&
1331             (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
1332              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1333                 return true;
1334
1335         if (ieee80211_802_1x_port_control(rx) ||
1336             ieee80211_drop_unencrypted(rx, fc))
1337                 return false;
1338
1339         return true;
1340 }
1341
1342 /*
1343  * requires that rx->skb is a frame with ethernet header
1344  */
1345 static void
1346 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1347 {
1348         struct net_device *dev = rx->dev;
1349         struct ieee80211_local *local = rx->local;
1350         struct sk_buff *skb, *xmit_skb;
1351         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1352         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1353         struct sta_info *dsta;
1354
1355         skb = rx->skb;
1356         xmit_skb = NULL;
1357
1358         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1359              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1360             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1361             (rx->flags & IEEE80211_RX_RA_MATCH)) {
1362                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1363                         /*
1364                          * send multicast frames both to higher layers in
1365                          * local net stack and back to the wireless medium
1366                          */
1367                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1368                         if (!xmit_skb && net_ratelimit())
1369                                 printk(KERN_DEBUG "%s: failed to clone "
1370                                        "multicast frame\n", dev->name);
1371                 } else {
1372                         dsta = sta_info_get(local, skb->data);
1373                         if (dsta && dsta->sdata->dev == dev) {
1374                                 /*
1375                                  * The destination station is associated to
1376                                  * this AP (in this VLAN), so send the frame
1377                                  * directly to it and do not pass it to local
1378                                  * net stack.
1379                                  */
1380                                 xmit_skb = skb;
1381                                 skb = NULL;
1382                         }
1383                 }
1384         }
1385
1386         if (skb) {
1387                 int align __maybe_unused;
1388
1389 #if defined(CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT) || !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
1390                 /*
1391                  * 'align' will only take the values 0 or 2 here
1392                  * since all frames are required to be aligned
1393                  * to 2-byte boundaries when being passed to
1394                  * mac80211. That also explains the __skb_push()
1395                  * below.
1396                  */
1397                 align = (unsigned long)skb->data & 3;
1398                 if (align) {
1399                         if (WARN_ON(skb_headroom(skb) < 3)) {
1400                                 dev_kfree_skb(skb);
1401                                 skb = NULL;
1402                         } else {
1403                                 u8 *data = skb->data;
1404                                 size_t len = skb->len;
1405                                 u8 *new = __skb_push(skb, align);
1406                                 memmove(new, data, len);
1407                                 __skb_trim(skb, len);
1408                         }
1409                 }
1410 #endif
1411
1412                 if (skb) {
1413                         /* deliver to local stack */
1414                         skb->protocol = eth_type_trans(skb, dev);
1415                         memset(skb->cb, 0, sizeof(skb->cb));
1416                         netif_rx(skb);
1417                 }
1418         }
1419
1420         if (xmit_skb) {
1421                 /* send to wireless media */
1422                 xmit_skb->protocol = htons(ETH_P_802_3);
1423                 skb_reset_network_header(xmit_skb);
1424                 skb_reset_mac_header(xmit_skb);
1425                 dev_queue_xmit(xmit_skb);
1426         }
1427 }
1428
1429 static ieee80211_rx_result debug_noinline
1430 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1431 {
1432         struct net_device *dev = rx->dev;
1433         struct ieee80211_local *local = rx->local;
1434         u16 ethertype;
1435         u8 *payload;
1436         struct sk_buff *skb = rx->skb, *frame = NULL;
1437         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1438         __le16 fc = hdr->frame_control;
1439         const struct ethhdr *eth;
1440         int remaining, err;
1441         u8 dst[ETH_ALEN];
1442         u8 src[ETH_ALEN];
1443
1444         if (unlikely(!ieee80211_is_data(fc)))
1445                 return RX_CONTINUE;
1446
1447         if (unlikely(!ieee80211_is_data_present(fc)))
1448                 return RX_DROP_MONITOR;
1449
1450         if (!(rx->flags & IEEE80211_RX_AMSDU))
1451                 return RX_CONTINUE;
1452
1453         err = ieee80211_data_to_8023(rx);
1454         if (unlikely(err))
1455                 return RX_DROP_UNUSABLE;
1456
1457         skb->dev = dev;
1458
1459         dev->stats.rx_packets++;
1460         dev->stats.rx_bytes += skb->len;
1461
1462         /* skip the wrapping header */
1463         eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
1464         if (!eth)
1465                 return RX_DROP_UNUSABLE;
1466
1467         while (skb != frame) {
1468                 u8 padding;
1469                 __be16 len = eth->h_proto;
1470                 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
1471
1472                 remaining = skb->len;
1473                 memcpy(dst, eth->h_dest, ETH_ALEN);
1474                 memcpy(src, eth->h_source, ETH_ALEN);
1475
1476                 padding = ((4 - subframe_len) & 0x3);
1477                 /* the last MSDU has no padding */
1478                 if (subframe_len > remaining)
1479                         return RX_DROP_UNUSABLE;
1480
1481                 skb_pull(skb, sizeof(struct ethhdr));
1482                 /* if last subframe reuse skb */
1483                 if (remaining <= subframe_len + padding)
1484                         frame = skb;
1485                 else {
1486                         /*
1487                          * Allocate and reserve two bytes more for payload
1488                          * alignment since sizeof(struct ethhdr) is 14.
1489                          */
1490                         frame = dev_alloc_skb(
1491                                 ALIGN(local->hw.extra_tx_headroom, 4) +
1492                                 subframe_len + 2);
1493
1494                         if (frame == NULL)
1495                                 return RX_DROP_UNUSABLE;
1496
1497                         skb_reserve(frame,
1498                                     ALIGN(local->hw.extra_tx_headroom, 4) +
1499                                     sizeof(struct ethhdr) + 2);
1500                         memcpy(skb_put(frame, ntohs(len)), skb->data,
1501                                 ntohs(len));
1502
1503                         eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
1504                                                         padding);
1505                         if (!eth) {
1506                                 dev_kfree_skb(frame);
1507                                 return RX_DROP_UNUSABLE;
1508                         }
1509                 }
1510
1511                 skb_reset_network_header(frame);
1512                 frame->dev = dev;
1513                 frame->priority = skb->priority;
1514                 rx->skb = frame;
1515
1516                 payload = frame->data;
1517                 ethertype = (payload[6] << 8) | payload[7];
1518
1519                 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1520                             ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1521                            compare_ether_addr(payload,
1522                                               bridge_tunnel_header) == 0)) {
1523                         /* remove RFC1042 or Bridge-Tunnel
1524                          * encapsulation and replace EtherType */
1525                         skb_pull(frame, 6);
1526                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1527                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1528                 } else {
1529                         memcpy(skb_push(frame, sizeof(__be16)),
1530                                &len, sizeof(__be16));
1531                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1532                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1533                 }
1534
1535                 if (!ieee80211_frame_allowed(rx, fc)) {
1536                         if (skb == frame) /* last frame */
1537                                 return RX_DROP_UNUSABLE;
1538                         dev_kfree_skb(frame);
1539                         continue;
1540                 }
1541
1542                 ieee80211_deliver_skb(rx);
1543         }
1544
1545         return RX_QUEUED;
1546 }
1547
1548 #ifdef CONFIG_MAC80211_MESH
1549 static ieee80211_rx_result
1550 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1551 {
1552         struct ieee80211_hdr *hdr;
1553         struct ieee80211s_hdr *mesh_hdr;
1554         unsigned int hdrlen;
1555         struct sk_buff *skb = rx->skb, *fwd_skb;
1556
1557         hdr = (struct ieee80211_hdr *) skb->data;
1558         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1559         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1560
1561         if (!ieee80211_is_data(hdr->frame_control))
1562                 return RX_CONTINUE;
1563
1564         if (!mesh_hdr->ttl)
1565                 /* illegal frame */
1566                 return RX_DROP_MONITOR;
1567
1568         if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6){
1569                 struct ieee80211_sub_if_data *sdata;
1570                 struct mesh_path *mppath;
1571
1572                 sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1573                 rcu_read_lock();
1574                 mppath = mpp_path_lookup(mesh_hdr->eaddr2, sdata);
1575                 if (!mppath) {
1576                         mpp_path_add(mesh_hdr->eaddr2, hdr->addr4, sdata);
1577                 } else {
1578                         spin_lock_bh(&mppath->state_lock);
1579                         mppath->exp_time = jiffies;
1580                         if (compare_ether_addr(mppath->mpp, hdr->addr4) != 0)
1581                                 memcpy(mppath->mpp, hdr->addr4, ETH_ALEN);
1582                         spin_unlock_bh(&mppath->state_lock);
1583                 }
1584                 rcu_read_unlock();
1585         }
1586
1587         if (compare_ether_addr(rx->dev->dev_addr, hdr->addr3) == 0)
1588                 return RX_CONTINUE;
1589
1590         mesh_hdr->ttl--;
1591
1592         if (rx->flags & IEEE80211_RX_RA_MATCH) {
1593                 if (!mesh_hdr->ttl)
1594                         IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1595                                                      dropped_frames_ttl);
1596                 else {
1597                         struct ieee80211_hdr *fwd_hdr;
1598                         fwd_skb = skb_copy(skb, GFP_ATOMIC);
1599
1600                         if (!fwd_skb && net_ratelimit())
1601                                 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1602                                                    rx->dev->name);
1603
1604                         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1605                         /*
1606                          * Save TA to addr1 to send TA a path error if a
1607                          * suitable next hop is not found
1608                          */
1609                         memcpy(fwd_hdr->addr1, fwd_hdr->addr2, ETH_ALEN);
1610                         memcpy(fwd_hdr->addr2, rx->dev->dev_addr, ETH_ALEN);
1611                         fwd_skb->dev = rx->local->mdev;
1612                         fwd_skb->iif = rx->dev->ifindex;
1613                         dev_queue_xmit(fwd_skb);
1614                 }
1615         }
1616
1617         if (is_multicast_ether_addr(hdr->addr3) ||
1618             rx->dev->flags & IFF_PROMISC)
1619                 return RX_CONTINUE;
1620         else
1621                 return RX_DROP_MONITOR;
1622 }
1623 #endif
1624
1625 static ieee80211_rx_result debug_noinline
1626 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1627 {
1628         struct net_device *dev = rx->dev;
1629         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1630         __le16 fc = hdr->frame_control;
1631         int err;
1632
1633         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1634                 return RX_CONTINUE;
1635
1636         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1637                 return RX_DROP_MONITOR;
1638
1639         err = ieee80211_data_to_8023(rx);
1640         if (unlikely(err))
1641                 return RX_DROP_UNUSABLE;
1642
1643         if (!ieee80211_frame_allowed(rx, fc))
1644                 return RX_DROP_MONITOR;
1645
1646         rx->skb->dev = dev;
1647
1648         dev->stats.rx_packets++;
1649         dev->stats.rx_bytes += rx->skb->len;
1650
1651         ieee80211_deliver_skb(rx);
1652
1653         return RX_QUEUED;
1654 }
1655
1656 static ieee80211_rx_result debug_noinline
1657 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
1658 {
1659         struct ieee80211_local *local = rx->local;
1660         struct ieee80211_hw *hw = &local->hw;
1661         struct sk_buff *skb = rx->skb;
1662         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1663         struct tid_ampdu_rx *tid_agg_rx;
1664         u16 start_seq_num;
1665         u16 tid;
1666
1667         if (likely(!ieee80211_is_ctl(bar->frame_control)))
1668                 return RX_CONTINUE;
1669
1670         if (ieee80211_is_back_req(bar->frame_control)) {
1671                 if (!rx->sta)
1672                         return RX_CONTINUE;
1673                 tid = le16_to_cpu(bar->control) >> 12;
1674                 if (rx->sta->ampdu_mlme.tid_state_rx[tid]
1675                                         != HT_AGG_STATE_OPERATIONAL)
1676                         return RX_CONTINUE;
1677                 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid];
1678
1679                 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1680
1681                 /* reset session timer */
1682                 if (tid_agg_rx->timeout)
1683                         mod_timer(&tid_agg_rx->session_timer,
1684                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
1685
1686                 /* manage reordering buffer according to requested */
1687                 /* sequence number */
1688                 rcu_read_lock();
1689                 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL, NULL,
1690                                                  start_seq_num, 1);
1691                 rcu_read_unlock();
1692                 return RX_DROP_UNUSABLE;
1693         }
1694
1695         return RX_CONTINUE;
1696 }
1697
1698 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
1699                                            struct ieee80211_mgmt *mgmt,
1700                                            size_t len)
1701 {
1702         struct ieee80211_local *local = sdata->local;
1703         struct sk_buff *skb;
1704         struct ieee80211_mgmt *resp;
1705
1706         if (compare_ether_addr(mgmt->da, sdata->dev->dev_addr) != 0) {
1707                 /* Not to own unicast address */
1708                 return;
1709         }
1710
1711         if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
1712             compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
1713                 /* Not from the current AP. */
1714                 return;
1715         }
1716
1717         if (sdata->u.mgd.state == IEEE80211_STA_MLME_ASSOCIATE) {
1718                 /* Association in progress; ignore SA Query */
1719                 return;
1720         }
1721
1722         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
1723                 /* Too short SA Query request frame */
1724                 return;
1725         }
1726
1727         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
1728         if (skb == NULL)
1729                 return;
1730
1731         skb_reserve(skb, local->hw.extra_tx_headroom);
1732         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
1733         memset(resp, 0, 24);
1734         memcpy(resp->da, mgmt->sa, ETH_ALEN);
1735         memcpy(resp->sa, sdata->dev->dev_addr, ETH_ALEN);
1736         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
1737         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1738                                           IEEE80211_STYPE_ACTION);
1739         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
1740         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
1741         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
1742         memcpy(resp->u.action.u.sa_query.trans_id,
1743                mgmt->u.action.u.sa_query.trans_id,
1744                WLAN_SA_QUERY_TR_ID_LEN);
1745
1746         ieee80211_tx_skb(sdata, skb, 1);
1747 }
1748
1749 static ieee80211_rx_result debug_noinline
1750 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
1751 {
1752         struct ieee80211_local *local = rx->local;
1753         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1754         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1755         struct ieee80211_bss *bss;
1756         int len = rx->skb->len;
1757
1758         if (!ieee80211_is_action(mgmt->frame_control))
1759                 return RX_CONTINUE;
1760
1761         if (!rx->sta)
1762                 return RX_DROP_MONITOR;
1763
1764         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1765                 return RX_DROP_MONITOR;
1766
1767         if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
1768                 return RX_DROP_MONITOR;
1769
1770         /* all categories we currently handle have action_code */
1771         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
1772                 return RX_DROP_MONITOR;
1773
1774         switch (mgmt->u.action.category) {
1775         case WLAN_CATEGORY_BACK:
1776                 /*
1777                  * The aggregation code is not prepared to handle
1778                  * anything but STA/AP due to the BSSID handling;
1779                  * IBSS could work in the code but isn't supported
1780                  * by drivers or the standard.
1781                  */
1782                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
1783                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
1784                     sdata->vif.type != NL80211_IFTYPE_AP)
1785                         return RX_DROP_MONITOR;
1786
1787                 switch (mgmt->u.action.u.addba_req.action_code) {
1788                 case WLAN_ACTION_ADDBA_REQ:
1789                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1790                                    sizeof(mgmt->u.action.u.addba_req)))
1791                                 return RX_DROP_MONITOR;
1792                         ieee80211_process_addba_request(local, rx->sta, mgmt, len);
1793                         break;
1794                 case WLAN_ACTION_ADDBA_RESP:
1795                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1796                                    sizeof(mgmt->u.action.u.addba_resp)))
1797                                 return RX_DROP_MONITOR;
1798                         ieee80211_process_addba_resp(local, rx->sta, mgmt, len);
1799                         break;
1800                 case WLAN_ACTION_DELBA:
1801                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1802                                    sizeof(mgmt->u.action.u.delba)))
1803                                 return RX_DROP_MONITOR;
1804                         ieee80211_process_delba(sdata, rx->sta, mgmt, len);
1805                         break;
1806                 }
1807                 break;
1808         case WLAN_CATEGORY_SPECTRUM_MGMT:
1809                 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
1810                         return RX_DROP_MONITOR;
1811
1812                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
1813                         return RX_DROP_MONITOR;
1814
1815                 switch (mgmt->u.action.u.measurement.action_code) {
1816                 case WLAN_ACTION_SPCT_MSR_REQ:
1817                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1818                                    sizeof(mgmt->u.action.u.measurement)))
1819                                 return RX_DROP_MONITOR;
1820                         ieee80211_process_measurement_req(sdata, mgmt, len);
1821                         break;
1822                 case WLAN_ACTION_SPCT_CHL_SWITCH:
1823                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1824                                    sizeof(mgmt->u.action.u.chan_switch)))
1825                                 return RX_DROP_MONITOR;
1826
1827                         if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
1828                                 return RX_DROP_MONITOR;
1829
1830                         bss = ieee80211_rx_bss_get(local, sdata->u.mgd.bssid,
1831                                            local->hw.conf.channel->center_freq,
1832                                            sdata->u.mgd.ssid,
1833                                            sdata->u.mgd.ssid_len);
1834                         if (!bss)
1835                                 return RX_DROP_MONITOR;
1836
1837                         ieee80211_process_chanswitch(sdata,
1838                                      &mgmt->u.action.u.chan_switch.sw_elem, bss);
1839                         ieee80211_rx_bss_put(local, bss);
1840                         break;
1841                 }
1842                 break;
1843         case WLAN_CATEGORY_SA_QUERY:
1844                 if (len < (IEEE80211_MIN_ACTION_SIZE +
1845                            sizeof(mgmt->u.action.u.sa_query)))
1846                         return RX_DROP_MONITOR;
1847                 switch (mgmt->u.action.u.sa_query.action) {
1848                 case WLAN_ACTION_SA_QUERY_REQUEST:
1849                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
1850                                 return RX_DROP_MONITOR;
1851                         ieee80211_process_sa_query_req(sdata, mgmt, len);
1852                         break;
1853                 case WLAN_ACTION_SA_QUERY_RESPONSE:
1854                         /*
1855                          * SA Query response is currently only used in AP mode
1856                          * and it is processed in user space.
1857                          */
1858                         return RX_CONTINUE;
1859                 }
1860                 break;
1861         default:
1862                 return RX_CONTINUE;
1863         }
1864
1865         rx->sta->rx_packets++;
1866         dev_kfree_skb(rx->skb);
1867         return RX_QUEUED;
1868 }
1869
1870 static ieee80211_rx_result debug_noinline
1871 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
1872 {
1873         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1874         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1875
1876         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1877                 return RX_DROP_MONITOR;
1878
1879         if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
1880                 return RX_DROP_MONITOR;
1881
1882         if (ieee80211_vif_is_mesh(&sdata->vif))
1883                 return ieee80211_mesh_rx_mgmt(sdata, rx->skb, rx->status);
1884
1885         if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
1886                 return ieee80211_ibss_rx_mgmt(sdata, rx->skb, rx->status);
1887
1888         if (sdata->vif.type == NL80211_IFTYPE_STATION)
1889                 return ieee80211_sta_rx_mgmt(sdata, rx->skb, rx->status);
1890
1891         return RX_DROP_MONITOR;
1892 }
1893
1894 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1895                                             struct ieee80211_hdr *hdr,
1896                                             struct ieee80211_rx_data *rx)
1897 {
1898         int keyidx;
1899         unsigned int hdrlen;
1900
1901         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1902         if (rx->skb->len >= hdrlen + 4)
1903                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1904         else
1905                 keyidx = -1;
1906
1907         if (!rx->sta) {
1908                 /*
1909                  * Some hardware seem to generate incorrect Michael MIC
1910                  * reports; ignore them to avoid triggering countermeasures.
1911                  */
1912                 goto ignore;
1913         }
1914
1915         if (!ieee80211_has_protected(hdr->frame_control))
1916                 goto ignore;
1917
1918         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
1919                 /*
1920                  * APs with pairwise keys should never receive Michael MIC
1921                  * errors for non-zero keyidx because these are reserved for
1922                  * group keys and only the AP is sending real multicast
1923                  * frames in the BSS.
1924                  */
1925                 goto ignore;
1926         }
1927
1928         if (!ieee80211_is_data(hdr->frame_control) &&
1929             !ieee80211_is_auth(hdr->frame_control))
1930                 goto ignore;
1931
1932         mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL);
1933  ignore:
1934         dev_kfree_skb(rx->skb);
1935         rx->skb = NULL;
1936 }
1937
1938 /* TODO: use IEEE80211_RX_FRAGMENTED */
1939 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx)
1940 {
1941         struct ieee80211_sub_if_data *sdata;
1942         struct ieee80211_local *local = rx->local;
1943         struct ieee80211_rtap_hdr {
1944                 struct ieee80211_radiotap_header hdr;
1945                 u8 flags;
1946                 u8 rate;
1947                 __le16 chan_freq;
1948                 __le16 chan_flags;
1949         } __attribute__ ((packed)) *rthdr;
1950         struct sk_buff *skb = rx->skb, *skb2;
1951         struct net_device *prev_dev = NULL;
1952         struct ieee80211_rx_status *status = rx->status;
1953
1954         if (rx->flags & IEEE80211_RX_CMNTR_REPORTED)
1955                 goto out_free_skb;
1956
1957         if (skb_headroom(skb) < sizeof(*rthdr) &&
1958             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
1959                 goto out_free_skb;
1960
1961         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
1962         memset(rthdr, 0, sizeof(*rthdr));
1963         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
1964         rthdr->hdr.it_present =
1965                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
1966                             (1 << IEEE80211_RADIOTAP_RATE) |
1967                             (1 << IEEE80211_RADIOTAP_CHANNEL));
1968
1969         rthdr->rate = rx->rate->bitrate / 5;
1970         rthdr->chan_freq = cpu_to_le16(status->freq);
1971
1972         if (status->band == IEEE80211_BAND_5GHZ)
1973                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
1974                                                 IEEE80211_CHAN_5GHZ);
1975         else
1976                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
1977                                                 IEEE80211_CHAN_2GHZ);
1978
1979         skb_set_mac_header(skb, 0);
1980         skb->ip_summed = CHECKSUM_UNNECESSARY;
1981         skb->pkt_type = PACKET_OTHERHOST;
1982         skb->protocol = htons(ETH_P_802_2);
1983
1984         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1985                 if (!netif_running(sdata->dev))
1986                         continue;
1987
1988                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
1989                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
1990                         continue;
1991
1992                 if (prev_dev) {
1993                         skb2 = skb_clone(skb, GFP_ATOMIC);
1994                         if (skb2) {
1995                                 skb2->dev = prev_dev;
1996                                 netif_rx(skb2);
1997                         }
1998                 }
1999
2000                 prev_dev = sdata->dev;
2001                 sdata->dev->stats.rx_packets++;
2002                 sdata->dev->stats.rx_bytes += skb->len;
2003         }
2004
2005         if (prev_dev) {
2006                 skb->dev = prev_dev;
2007                 netif_rx(skb);
2008                 skb = NULL;
2009         } else
2010                 goto out_free_skb;
2011
2012         rx->flags |= IEEE80211_RX_CMNTR_REPORTED;
2013         return;
2014
2015  out_free_skb:
2016         dev_kfree_skb(skb);
2017 }
2018
2019
2020 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
2021                                          struct ieee80211_rx_data *rx,
2022                                          struct sk_buff *skb)
2023 {
2024         ieee80211_rx_result res = RX_DROP_MONITOR;
2025
2026         rx->skb = skb;
2027         rx->sdata = sdata;
2028         rx->dev = sdata->dev;
2029
2030 #define CALL_RXH(rxh)                   \
2031         do {                            \
2032                 res = rxh(rx);          \
2033                 if (res != RX_CONTINUE) \
2034                         goto rxh_done;  \
2035         } while (0);
2036
2037         CALL_RXH(ieee80211_rx_h_passive_scan)
2038         CALL_RXH(ieee80211_rx_h_check)
2039         CALL_RXH(ieee80211_rx_h_decrypt)
2040         CALL_RXH(ieee80211_rx_h_check_more_data)
2041         CALL_RXH(ieee80211_rx_h_sta_process)
2042         CALL_RXH(ieee80211_rx_h_defragment)
2043         CALL_RXH(ieee80211_rx_h_ps_poll)
2044         CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2045         /* must be after MMIC verify so header is counted in MPDU mic */
2046         CALL_RXH(ieee80211_rx_h_remove_qos_control)
2047         CALL_RXH(ieee80211_rx_h_amsdu)
2048 #ifdef CONFIG_MAC80211_MESH
2049         if (ieee80211_vif_is_mesh(&sdata->vif))
2050                 CALL_RXH(ieee80211_rx_h_mesh_fwding);
2051 #endif
2052         CALL_RXH(ieee80211_rx_h_data)
2053         CALL_RXH(ieee80211_rx_h_ctrl)
2054         CALL_RXH(ieee80211_rx_h_action)
2055         CALL_RXH(ieee80211_rx_h_mgmt)
2056
2057 #undef CALL_RXH
2058
2059  rxh_done:
2060         switch (res) {
2061         case RX_DROP_MONITOR:
2062                 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2063                 if (rx->sta)
2064                         rx->sta->rx_dropped++;
2065                 /* fall through */
2066         case RX_CONTINUE:
2067                 ieee80211_rx_cooked_monitor(rx);
2068                 break;
2069         case RX_DROP_UNUSABLE:
2070                 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2071                 if (rx->sta)
2072                         rx->sta->rx_dropped++;
2073                 dev_kfree_skb(rx->skb);
2074                 break;
2075         case RX_QUEUED:
2076                 I802_DEBUG_INC(sdata->local->rx_handlers_queued);
2077                 break;
2078         }
2079 }
2080
2081 /* main receive path */
2082
2083 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
2084                                 struct ieee80211_rx_data *rx,
2085                                 struct ieee80211_hdr *hdr)
2086 {
2087         u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, sdata->vif.type);
2088         int multicast = is_multicast_ether_addr(hdr->addr1);
2089
2090         switch (sdata->vif.type) {
2091         case NL80211_IFTYPE_STATION:
2092                 if (!bssid)
2093                         return 0;
2094                 if (!ieee80211_bssid_match(bssid, sdata->u.mgd.bssid)) {
2095                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2096                                 return 0;
2097                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2098                 } else if (!multicast &&
2099                            compare_ether_addr(sdata->dev->dev_addr,
2100                                               hdr->addr1) != 0) {
2101                         if (!(sdata->dev->flags & IFF_PROMISC))
2102                                 return 0;
2103                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2104                 }
2105                 break;
2106         case NL80211_IFTYPE_ADHOC:
2107                 if (!bssid)
2108                         return 0;
2109                 if (ieee80211_is_beacon(hdr->frame_control)) {
2110                         return 1;
2111                 }
2112                 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2113                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2114                                 return 0;
2115                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2116                 } else if (!multicast &&
2117                            compare_ether_addr(sdata->dev->dev_addr,
2118                                               hdr->addr1) != 0) {
2119                         if (!(sdata->dev->flags & IFF_PROMISC))
2120                                 return 0;
2121                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2122                 } else if (!rx->sta) {
2123                         int rate_idx;
2124                         if (rx->status->flag & RX_FLAG_HT)
2125                                 rate_idx = 0; /* TODO: HT rates */
2126                         else
2127                                 rate_idx = rx->status->rate_idx;
2128                         rx->sta = ieee80211_ibss_add_sta(sdata, bssid, hdr->addr2,
2129                                 BIT(rate_idx));
2130                 }
2131                 break;
2132         case NL80211_IFTYPE_MESH_POINT:
2133                 if (!multicast &&
2134                     compare_ether_addr(sdata->dev->dev_addr,
2135                                        hdr->addr1) != 0) {
2136                         if (!(sdata->dev->flags & IFF_PROMISC))
2137                                 return 0;
2138
2139                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2140                 }
2141                 break;
2142         case NL80211_IFTYPE_AP_VLAN:
2143         case NL80211_IFTYPE_AP:
2144                 if (!bssid) {
2145                         if (compare_ether_addr(sdata->dev->dev_addr,
2146                                                hdr->addr1))
2147                                 return 0;
2148                 } else if (!ieee80211_bssid_match(bssid,
2149                                         sdata->dev->dev_addr)) {
2150                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2151                                 return 0;
2152                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2153                 }
2154                 break;
2155         case NL80211_IFTYPE_WDS:
2156                 if (bssid || !ieee80211_is_data(hdr->frame_control))
2157                         return 0;
2158                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2159                         return 0;
2160                 break;
2161         case NL80211_IFTYPE_MONITOR:
2162                 /* take everything */
2163                 break;
2164         case NL80211_IFTYPE_UNSPECIFIED:
2165         case __NL80211_IFTYPE_AFTER_LAST:
2166                 /* should never get here */
2167                 WARN_ON(1);
2168                 break;
2169         }
2170
2171         return 1;
2172 }
2173
2174 /*
2175  * This is the actual Rx frames handler. as it blongs to Rx path it must
2176  * be called with rcu_read_lock protection.
2177  */
2178 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2179                                          struct sk_buff *skb,
2180                                          struct ieee80211_rx_status *status,
2181                                          struct ieee80211_rate *rate)
2182 {
2183         struct ieee80211_local *local = hw_to_local(hw);
2184         struct ieee80211_sub_if_data *sdata;
2185         struct ieee80211_hdr *hdr;
2186         struct ieee80211_rx_data rx;
2187         int prepares;
2188         struct ieee80211_sub_if_data *prev = NULL;
2189         struct sk_buff *skb_new;
2190
2191         hdr = (struct ieee80211_hdr *)skb->data;
2192         memset(&rx, 0, sizeof(rx));
2193         rx.skb = skb;
2194         rx.local = local;
2195
2196         rx.status = status;
2197         rx.rate = rate;
2198
2199         if (ieee80211_is_data(hdr->frame_control) || ieee80211_is_mgmt(hdr->frame_control))
2200                 local->dot11ReceivedFragmentCount++;
2201
2202         rx.sta = sta_info_get(local, hdr->addr2);
2203         if (rx.sta) {
2204                 rx.sdata = rx.sta->sdata;
2205                 rx.dev = rx.sta->sdata->dev;
2206         }
2207
2208         if ((status->flag & RX_FLAG_MMIC_ERROR)) {
2209                 ieee80211_rx_michael_mic_report(local->mdev, hdr, &rx);
2210                 return;
2211         }
2212
2213         if (unlikely(local->sw_scanning || local->hw_scanning))
2214                 rx.flags |= IEEE80211_RX_IN_SCAN;
2215
2216         ieee80211_parse_qos(&rx);
2217         ieee80211_verify_alignment(&rx);
2218
2219         skb = rx.skb;
2220
2221         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2222                 if (!netif_running(sdata->dev))
2223                         continue;
2224
2225                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR)
2226                         continue;
2227
2228                 rx.flags |= IEEE80211_RX_RA_MATCH;
2229                 prepares = prepare_for_handlers(sdata, &rx, hdr);
2230
2231                 if (!prepares)
2232                         continue;
2233
2234                 /*
2235                  * frame is destined for this interface, but if it's not
2236                  * also for the previous one we handle that after the
2237                  * loop to avoid copying the SKB once too much
2238                  */
2239
2240                 if (!prev) {
2241                         prev = sdata;
2242                         continue;
2243                 }
2244
2245                 /*
2246                  * frame was destined for the previous interface
2247                  * so invoke RX handlers for it
2248                  */
2249
2250                 skb_new = skb_copy(skb, GFP_ATOMIC);
2251                 if (!skb_new) {
2252                         if (net_ratelimit())
2253                                 printk(KERN_DEBUG "%s: failed to copy "
2254                                        "multicast frame for %s\n",
2255                                        wiphy_name(local->hw.wiphy),
2256                                        prev->dev->name);
2257                         continue;
2258                 }
2259                 ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
2260                 prev = sdata;
2261         }
2262         if (prev)
2263                 ieee80211_invoke_rx_handlers(prev, &rx, skb);
2264         else
2265                 dev_kfree_skb(skb);
2266 }
2267
2268 #define SEQ_MODULO 0x1000
2269 #define SEQ_MASK   0xfff
2270
2271 static inline int seq_less(u16 sq1, u16 sq2)
2272 {
2273         return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
2274 }
2275
2276 static inline u16 seq_inc(u16 sq)
2277 {
2278         return (sq + 1) & SEQ_MASK;
2279 }
2280
2281 static inline u16 seq_sub(u16 sq1, u16 sq2)
2282 {
2283         return (sq1 - sq2) & SEQ_MASK;
2284 }
2285
2286
2287 /*
2288  * As it function blongs to Rx path it must be called with
2289  * the proper rcu_read_lock protection for its flow.
2290  */
2291 static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
2292                                            struct tid_ampdu_rx *tid_agg_rx,
2293                                            struct sk_buff *skb,
2294                                            struct ieee80211_rx_status *rxstatus,
2295                                            u16 mpdu_seq_num,
2296                                            int bar_req)
2297 {
2298         struct ieee80211_local *local = hw_to_local(hw);
2299         struct ieee80211_rx_status status;
2300         u16 head_seq_num, buf_size;
2301         int index;
2302         struct ieee80211_supported_band *sband;
2303         struct ieee80211_rate *rate;
2304
2305         buf_size = tid_agg_rx->buf_size;
2306         head_seq_num = tid_agg_rx->head_seq_num;
2307
2308         /* frame with out of date sequence number */
2309         if (seq_less(mpdu_seq_num, head_seq_num)) {
2310                 dev_kfree_skb(skb);
2311                 return 1;
2312         }
2313
2314         /* if frame sequence number exceeds our buffering window size or
2315          * block Ack Request arrived - release stored frames */
2316         if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
2317                 /* new head to the ordering buffer */
2318                 if (bar_req)
2319                         head_seq_num = mpdu_seq_num;
2320                 else
2321                         head_seq_num =
2322                                 seq_inc(seq_sub(mpdu_seq_num, buf_size));
2323                 /* release stored frames up to new head to stack */
2324                 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
2325                         index = seq_sub(tid_agg_rx->head_seq_num,
2326                                 tid_agg_rx->ssn)
2327                                 % tid_agg_rx->buf_size;
2328
2329                         if (tid_agg_rx->reorder_buf[index]) {
2330                                 /* release the reordered frames to stack */
2331                                 memcpy(&status,
2332                                         tid_agg_rx->reorder_buf[index]->cb,
2333                                         sizeof(status));
2334                                 sband = local->hw.wiphy->bands[status.band];
2335                                 if (status.flag & RX_FLAG_HT) {
2336                                         /* TODO: HT rates */
2337                                         rate = sband->bitrates;
2338                                 } else {
2339                                         rate = &sband->bitrates
2340                                                 [status.rate_idx];
2341                                 }
2342                                 __ieee80211_rx_handle_packet(hw,
2343                                         tid_agg_rx->reorder_buf[index],
2344                                         &status, rate);
2345                                 tid_agg_rx->stored_mpdu_num--;
2346                                 tid_agg_rx->reorder_buf[index] = NULL;
2347                         }
2348                         tid_agg_rx->head_seq_num =
2349                                 seq_inc(tid_agg_rx->head_seq_num);
2350                 }
2351                 if (bar_req)
2352                         return 1;
2353         }
2354
2355         /* now the new frame is always in the range of the reordering */
2356         /* buffer window */
2357         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
2358                                 % tid_agg_rx->buf_size;
2359         /* check if we already stored this frame */
2360         if (tid_agg_rx->reorder_buf[index]) {
2361                 dev_kfree_skb(skb);
2362                 return 1;
2363         }
2364
2365         /* if arrived mpdu is in the right order and nothing else stored */
2366         /* release it immediately */
2367         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
2368                         tid_agg_rx->stored_mpdu_num == 0) {
2369                 tid_agg_rx->head_seq_num =
2370                         seq_inc(tid_agg_rx->head_seq_num);
2371                 return 0;
2372         }
2373
2374         /* put the frame in the reordering buffer */
2375         tid_agg_rx->reorder_buf[index] = skb;
2376         memcpy(tid_agg_rx->reorder_buf[index]->cb, rxstatus,
2377                sizeof(*rxstatus));
2378         tid_agg_rx->stored_mpdu_num++;
2379         /* release the buffer until next missing frame */
2380         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
2381                                                 % tid_agg_rx->buf_size;
2382         while (tid_agg_rx->reorder_buf[index]) {
2383                 /* release the reordered frame back to stack */
2384                 memcpy(&status, tid_agg_rx->reorder_buf[index]->cb,
2385                         sizeof(status));
2386                 sband = local->hw.wiphy->bands[status.band];
2387                 if (status.flag & RX_FLAG_HT)
2388                         rate = sband->bitrates; /* TODO: HT rates */
2389                 else
2390                         rate = &sband->bitrates[status.rate_idx];
2391                 __ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index],
2392                                              &status, rate);
2393                 tid_agg_rx->stored_mpdu_num--;
2394                 tid_agg_rx->reorder_buf[index] = NULL;
2395                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
2396                 index = seq_sub(tid_agg_rx->head_seq_num,
2397                         tid_agg_rx->ssn) % tid_agg_rx->buf_size;
2398         }
2399         return 1;
2400 }
2401
2402 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
2403                                      struct sk_buff *skb,
2404                                      struct ieee80211_rx_status *status)
2405 {
2406         struct ieee80211_hw *hw = &local->hw;
2407         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
2408         struct sta_info *sta;
2409         struct tid_ampdu_rx *tid_agg_rx;
2410         u16 sc;
2411         u16 mpdu_seq_num;
2412         u8 ret = 0;
2413         int tid;
2414
2415         sta = sta_info_get(local, hdr->addr2);
2416         if (!sta)
2417                 return ret;
2418
2419         /* filter the QoS data rx stream according to
2420          * STA/TID and check if this STA/TID is on aggregation */
2421         if (!ieee80211_is_data_qos(hdr->frame_control))
2422                 goto end_reorder;
2423
2424         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
2425
2426         if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
2427                 goto end_reorder;
2428
2429         tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
2430
2431         /* qos null data frames are excluded */
2432         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
2433                 goto end_reorder;
2434
2435         /* new un-ordered ampdu frame - process it */
2436
2437         /* reset session timer */
2438         if (tid_agg_rx->timeout)
2439                 mod_timer(&tid_agg_rx->session_timer,
2440                           TU_TO_EXP_TIME(tid_agg_rx->timeout));
2441
2442         /* if this mpdu is fragmented - terminate rx aggregation session */
2443         sc = le16_to_cpu(hdr->seq_ctrl);
2444         if (sc & IEEE80211_SCTL_FRAG) {
2445                 ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
2446                         tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
2447                 ret = 1;
2448                 goto end_reorder;
2449         }
2450
2451         /* according to mpdu sequence number deal with reordering buffer */
2452         mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
2453         ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb, status,
2454                                                 mpdu_seq_num, 0);
2455  end_reorder:
2456         return ret;
2457 }
2458
2459 /*
2460  * This is the receive path handler. It is called by a low level driver when an
2461  * 802.11 MPDU is received from the hardware.
2462  */
2463 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
2464                     struct ieee80211_rx_status *status)
2465 {
2466         struct ieee80211_local *local = hw_to_local(hw);
2467         struct ieee80211_rate *rate = NULL;
2468         struct ieee80211_supported_band *sband;
2469
2470         if (status->band < 0 ||
2471             status->band >= IEEE80211_NUM_BANDS) {
2472                 WARN_ON(1);
2473                 return;
2474         }
2475
2476         sband = local->hw.wiphy->bands[status->band];
2477         if (!sband) {
2478                 WARN_ON(1);
2479                 return;
2480         }
2481
2482         if (status->flag & RX_FLAG_HT) {
2483                 /* rate_idx is MCS index */
2484                 if (WARN_ON(status->rate_idx < 0 ||
2485                             status->rate_idx >= 76))
2486                         return;
2487                 /* HT rates are not in the table - use the highest legacy rate
2488                  * for now since other parts of mac80211 may not yet be fully
2489                  * MCS aware. */
2490                 rate = &sband->bitrates[sband->n_bitrates - 1];
2491         } else {
2492                 if (WARN_ON(status->rate_idx < 0 ||
2493                             status->rate_idx >= sband->n_bitrates))
2494                         return;
2495                 rate = &sband->bitrates[status->rate_idx];
2496         }
2497
2498         /*
2499          * key references and virtual interfaces are protected using RCU
2500          * and this requires that we are in a read-side RCU section during
2501          * receive processing
2502          */
2503         rcu_read_lock();
2504
2505         /*
2506          * Frames with failed FCS/PLCP checksum are not returned,
2507          * all other frames are returned without radiotap header
2508          * if it was previously present.
2509          * Also, frames with less than 16 bytes are dropped.
2510          */
2511         skb = ieee80211_rx_monitor(local, skb, status, rate);
2512         if (!skb) {
2513                 rcu_read_unlock();
2514                 return;
2515         }
2516
2517         if (!ieee80211_rx_reorder_ampdu(local, skb, status))
2518                 __ieee80211_rx_handle_packet(hw, skb, status, rate);
2519
2520         rcu_read_unlock();
2521 }
2522 EXPORT_SYMBOL(__ieee80211_rx);
2523
2524 /* This is a version of the rx handler that can be called from hard irq
2525  * context. Post the skb on the queue and schedule the tasklet */
2526 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
2527                           struct ieee80211_rx_status *status)
2528 {
2529         struct ieee80211_local *local = hw_to_local(hw);
2530
2531         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2532
2533         skb->dev = local->mdev;
2534         /* copy status into skb->cb for use by tasklet */
2535         memcpy(skb->cb, status, sizeof(*status));
2536         skb->pkt_type = IEEE80211_RX_MSG;
2537         skb_queue_tail(&local->skb_queue, skb);
2538         tasklet_schedule(&local->tasklet);
2539 }
2540 EXPORT_SYMBOL(ieee80211_rx_irqsafe);