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                                            u16 mpdu_seq_num,
  34                                            int bar_req);
  35 /*
  36  * monitor mode reception
  37  *
  38  * This function cleans up the SKB, i.e. it removes all the stuff
  39  * only useful for monitoring.
  40  */
  41 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
  42                                            struct sk_buff *skb)
  43 {
  44         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
  45                 if (likely(skb->len > FCS_LEN))
  46                         skb_trim(skb, skb->len - FCS_LEN);
  47                 else {
  48                         /* driver bug */
  49                         WARN_ON(1);
  50                         dev_kfree_skb(skb);
  51                         skb = NULL;
  52                 }
  53         }
  54
  55         return skb;
  56 }
  57
  58 static inline int should_drop_frame(struct sk_buff *skb,
  59                                     int present_fcs_len)
  60 {
  61         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  62         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  63
  64         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
  65                 return 1;
  66         if (unlikely(skb->len < 16 + present_fcs_len))
  67                 return 1;
  68         if (ieee80211_is_ctl(hdr->frame_control) &&
  69             !ieee80211_is_pspoll(hdr->frame_control) &&
  70             !ieee80211_is_back_req(hdr->frame_control))
  71                 return 1;
  72         return 0;
  73 }
  74
  75 static int
  76 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
  77                           struct ieee80211_rx_status *status)
  78 {
  79         int len;
  80
  81         /* always present fields */
  82         len = sizeof(struct ieee80211_radiotap_header) + 9;
  83
  84         if (status->flag & RX_FLAG_TSFT)
  85                 len += 8;
  86         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
  87                 len += 1;
  88         if (local->hw.flags & IEEE80211_HW_NOISE_DBM)
  89                 len += 1;
  90
  91         if (len & 1) /* padding for RX_FLAGS if necessary */
  92                 len++;
  93
  94         return len;
  95 }
  96
  97 /*
  98  * ieee80211_add_rx_radiotap_header - add radiotap header
  99  *
 100  * add a radiotap header containing all the fields which the hardware provided.
 101  */
 102 static void
 103 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
 104                                  struct sk_buff *skb,
 105                                  struct ieee80211_rate *rate,
 106                                  int rtap_len)
 107 {
 108         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 109         struct ieee80211_radiotap_header *rthdr;
 110         unsigned char *pos;
 111         u16 rx_flags = 0;
 112
 113         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
 114         memset(rthdr, 0, rtap_len);
 115
 116         /* radiotap header, set always present flags */
 117         rthdr->it_present =
 118                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 119                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
 120                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
 121                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
 122         rthdr->it_len = cpu_to_le16(rtap_len);
 123
 124         pos = (unsigned char *)(rthdr+1);
 125
 126         /* the order of the following fields is important */
 127
 128         /* IEEE80211_RADIOTAP_TSFT */
 129         if (status->flag & RX_FLAG_TSFT) {
 130                 put_unaligned_le64(status->mactime, pos);
 131                 rthdr->it_present |=
 132                         cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
 133                 pos += 8;
 134         }
 135
 136         /* IEEE80211_RADIOTAP_FLAGS */
 137         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 138                 *pos |= IEEE80211_RADIOTAP_F_FCS;
 139         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 140                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
 141         if (status->flag & RX_FLAG_SHORTPRE)
 142                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
 143         pos++;
 144
 145         /* IEEE80211_RADIOTAP_RATE */
 146         if (status->flag & RX_FLAG_HT) {
 147                 /*
 148                  * TODO: add following information into radiotap header once
 149                  * suitable fields are defined for it:
 150                  * - MCS index (status->rate_idx)
 151                  * - HT40 (status->flag & RX_FLAG_40MHZ)
 152                  * - short-GI (status->flag & RX_FLAG_SHORT_GI)
 153                  */
 154                 *pos = 0;
 155         } else {
 156                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
 157                 *pos = rate->bitrate / 5;
 158         }
 159         pos++;
 160
 161         /* IEEE80211_RADIOTAP_CHANNEL */
 162         put_unaligned_le16(status->freq, pos);
 163         pos += 2;
 164         if (status->band == IEEE80211_BAND_5GHZ)
 165                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
 166                                    pos);
 167         else if (rate->flags & IEEE80211_RATE_ERP_G)
 168                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
 169                                    pos);
 170         else
 171                 put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
 172                                    pos);
 173         pos += 2;
 174
 175         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
 176         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
 177                 *pos = status->signal;
 178                 rthdr->it_present |=
 179                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
 180                 pos++;
 181         }
 182
 183         /* IEEE80211_RADIOTAP_DBM_ANTNOISE */
 184         if (local->hw.flags & IEEE80211_HW_NOISE_DBM) {
 185                 *pos = status->noise;
 186                 rthdr->it_present |=
 187                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE);
 188                 pos++;
 189         }
 190
 191         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
 192
 193         /* IEEE80211_RADIOTAP_ANTENNA */
 194         *pos = status->antenna;
 195         pos++;
 196
 197         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
 198
 199         /* IEEE80211_RADIOTAP_RX_FLAGS */
 200         /* ensure 2 byte alignment for the 2 byte field as required */
 201         if ((pos - (u8 *)rthdr) & 1)
 202                 pos++;
 203         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
 204                 rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
 205         put_unaligned_le16(rx_flags, pos);
 206         pos += 2;
 207 }
 208
 209 /*
 210  * This function copies a received frame to all monitor interfaces and
 211  * returns a cleaned-up SKB that no longer includes the FCS nor the
 212  * radiotap header the driver might have added.
 213  */
 214 static struct sk_buff *
 215 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
 216                      struct ieee80211_rate *rate)
 217 {
 218         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
 219         struct ieee80211_sub_if_data *sdata;
 220         int needed_headroom = 0;
 221         struct sk_buff *skb, *skb2;
 222         struct net_device *prev_dev = NULL;
 223         int present_fcs_len = 0;
 224
 225         /*
 226          * First, we may need to make a copy of the skb because
 227          *  (1) we need to modify it for radiotap (if not present), and
 228          *  (2) the other RX handlers will modify the skb we got.
 229          *
 230          * We don't need to, of course, if we aren't going to return
 231          * the SKB because it has a bad FCS/PLCP checksum.
 232          */
 233
 234         /* room for the radiotap header based on driver features */
 235         needed_headroom = ieee80211_rx_radiotap_len(local, status);
 236
 237         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 238                 present_fcs_len = FCS_LEN;
 239
 240         if (!local->monitors) {
 241                 if (should_drop_frame(origskb, present_fcs_len)) {
 242                         dev_kfree_skb(origskb);
 243                         return NULL;
 244                 }
 245
 246                 return remove_monitor_info(local, origskb);
 247         }
 248
 249         if (should_drop_frame(origskb, present_fcs_len)) {
 250                 /* only need to expand headroom if necessary */
 251                 skb = origskb;
 252                 origskb = NULL;
 253
 254                 /*
 255                  * This shouldn't trigger often because most devices have an
 256                  * RX header they pull before we get here, and that should
 257                  * be big enough for our radiotap information. We should
 258                  * probably export the length to drivers so that we can have
 259                  * them allocate enough headroom to start with.
 260                  */
 261                 if (skb_headroom(skb) < needed_headroom &&
 262                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
 263                         dev_kfree_skb(skb);
 264                         return NULL;
 265                 }
 266         } else {
 267                 /*
 268                  * Need to make a copy and possibly remove radiotap header
 269                  * and FCS from the original.
 270                  */
 271                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
 272
 273                 origskb = remove_monitor_info(local, origskb);
 274
 275                 if (!skb)
 276                         return origskb;
 277         }
 278
 279         /* prepend radiotap information */
 280         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom);
 281
 282         skb_reset_mac_header(skb);
 283         skb->ip_summed = CHECKSUM_UNNECESSARY;
 284         skb->pkt_type = PACKET_OTHERHOST;
 285         skb->protocol = htons(ETH_P_802_2);
 286
 287         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 288                 if (!netif_running(sdata->dev))
 289                         continue;
 290
 291                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
 292                         continue;
 293
 294                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
 295                         continue;
 296
 297                 if (prev_dev) {
 298                         skb2 = skb_clone(skb, GFP_ATOMIC);
 299                         if (skb2) {
 300                                 skb2->dev = prev_dev;
 301                                 netif_rx(skb2);
 302                         }
 303                 }
 304
 305                 prev_dev = sdata->dev;
 306                 sdata->dev->stats.rx_packets++;
 307                 sdata->dev->stats.rx_bytes += skb->len;
 308         }
 309
 310         if (prev_dev) {
 311                 skb->dev = prev_dev;
 312                 netif_rx(skb);
 313         } else
 314                 dev_kfree_skb(skb);
 315
 316         return origskb;
 317 }
 318
 319
 320 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
 321 {
 322         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 323         int tid;
 324
 325         /* does the frame have a qos control field? */
 326         if (ieee80211_is_data_qos(hdr->frame_control)) {
 327                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 328                 /* frame has qos control */
 329                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
 330                 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
 331                         rx->flags |= IEEE80211_RX_AMSDU;
 332                 else
 333                         rx->flags &= ~IEEE80211_RX_AMSDU;
 334         } else {
 335                 /*
 336                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
 337                  *
 338                  *      Sequence numbers for management frames, QoS data
 339                  *      frames with a broadcast/multicast address in the
 340                  *      Address 1 field, and all non-QoS data frames sent
 341                  *      by QoS STAs are assigned using an additional single
 342                  *      modulo-4096 counter, [...]
 343                  *
 344                  * We also use that counter for non-QoS STAs.
 345                  */
 346                 tid = NUM_RX_DATA_QUEUES - 1;
 347         }
 348
 349         rx->queue = tid;
 350         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 351          * For now, set skb->priority to 0 for other cases. */
 352         rx->skb->priority = (tid > 7) ? 0 : tid;
 353 }
 354
 355 /**
 356  * DOC: Packet alignment
 357  *
 358  * Drivers always need to pass packets that are aligned to two-byte boundaries
 359  * to the stack.
 360  *
 361  * Additionally, should, if possible, align the payload data in a way that
 362  * guarantees that the contained IP header is aligned to a four-byte
 363  * boundary. In the case of regular frames, this simply means aligning the
 364  * payload to a four-byte boundary (because either the IP header is directly
 365  * contained, or IV/RFC1042 headers that have a length divisible by four are
 366  * in front of it).
 367  *
 368  * With A-MSDU frames, however, the payload data address must yield two modulo
 369  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
 370  * push the IP header further back to a multiple of four again. Thankfully, the
 371  * specs were sane enough this time around to require padding each A-MSDU
 372  * subframe to a length that is a multiple of four.
 373  *
 374  * Padding like Atheros hardware adds which is inbetween the 802.11 header and
 375  * the payload is not supported, the driver is required to move the 802.11
 376  * header to be directly in front of the payload in that case.
 377  */
 378 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
 379 {
 380         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 381         int hdrlen;
 382
 383 #ifndef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
 384         return;
 385 #endif
 386
 387         if (WARN_ONCE((unsigned long)rx->skb->data & 1,
 388                       "unaligned packet at 0x%p\n", rx->skb->data))
 389                 return;
 390
 391         if (!ieee80211_is_data_present(hdr->frame_control))
 392                 return;
 393
 394         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 395         if (rx->flags & IEEE80211_RX_AMSDU)
 396                 hdrlen += ETH_HLEN;
 397         WARN_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3,
 398                   "unaligned IP payload at 0x%p\n", rx->skb->data + hdrlen);
 399 }
 400
 401
 402 /* rx handlers */
 403
 404 static ieee80211_rx_result debug_noinline
 405 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
 406 {
 407         struct ieee80211_local *local = rx->local;
 408         struct sk_buff *skb = rx->skb;
 409
 410         if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning)))
 411                 return ieee80211_scan_rx(rx->sdata, skb);
 412
 413         if (unlikely(test_bit(SCAN_SW_SCANNING, &local->scanning) &&
 414                      (rx->flags & IEEE80211_RX_IN_SCAN))) {
 415                 /* drop all the other packets during a software scan anyway */
 416                 if (ieee80211_scan_rx(rx->sdata, skb) != RX_QUEUED)
 417                         dev_kfree_skb(skb);
 418                 return RX_QUEUED;
 419         }
 420
 421         if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
 422                 /* scanning finished during invoking of handlers */
 423                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
 424                 return RX_DROP_UNUSABLE;
 425         }
 426
 427         return RX_CONTINUE;
 428 }
 429
 430
 431 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
 432 {
 433         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 434
 435         if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
 436                 return 0;
 437
 438         return ieee80211_is_robust_mgmt_frame(hdr);
 439 }
 440
 441
 442 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
 443 {
 444         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 445
 446         if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
 447                 return 0;
 448
 449         return ieee80211_is_robust_mgmt_frame(hdr);
 450 }
 451
 452
 453 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
 454 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
 455 {
 456         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
 457         struct ieee80211_mmie *mmie;
 458
 459         if (skb->len < 24 + sizeof(*mmie) ||
 460             !is_multicast_ether_addr(hdr->da))
 461                 return -1;
 462
 463         if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
 464                 return -1; /* not a robust management frame */
 465
 466         mmie = (struct ieee80211_mmie *)
 467                 (skb->data + skb->len - sizeof(*mmie));
 468         if (mmie->element_id != WLAN_EID_MMIE ||
 469             mmie->length != sizeof(*mmie) - 2)
 470                 return -1;
 471
 472         return le16_to_cpu(mmie->key_id);
 473 }
 474
 475
 476 static ieee80211_rx_result
 477 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
 478 {
 479         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 480         unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
 481         char *dev_addr = rx->dev->dev_addr;
 482
 483         if (ieee80211_is_data(hdr->frame_control)) {
 484                 if (is_multicast_ether_addr(hdr->addr1)) {
 485                         if (ieee80211_has_tods(hdr->frame_control) ||
 486                                 !ieee80211_has_fromds(hdr->frame_control))
 487                                 return RX_DROP_MONITOR;
 488                         if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0)
 489                                 return RX_DROP_MONITOR;
 490                 } else {
 491                         if (!ieee80211_has_a4(hdr->frame_control))
 492                                 return RX_DROP_MONITOR;
 493                         if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0)
 494                                 return RX_DROP_MONITOR;
 495                 }
 496         }
 497
 498         /* If there is not an established peer link and this is not a peer link
 499          * establisment frame, beacon or probe, drop the frame.
 500          */
 501
 502         if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
 503                 struct ieee80211_mgmt *mgmt;
 504
 505                 if (!ieee80211_is_mgmt(hdr->frame_control))
 506                         return RX_DROP_MONITOR;
 507
 508                 if (ieee80211_is_action(hdr->frame_control)) {
 509                         mgmt = (struct ieee80211_mgmt *)hdr;
 510                         if (mgmt->u.action.category != MESH_PLINK_CATEGORY)
 511                                 return RX_DROP_MONITOR;
 512                         return RX_CONTINUE;
 513                 }
 514
 515                 if (ieee80211_is_probe_req(hdr->frame_control) ||
 516                     ieee80211_is_probe_resp(hdr->frame_control) ||
 517                     ieee80211_is_beacon(hdr->frame_control))
 518                         return RX_CONTINUE;
 519
 520                 return RX_DROP_MONITOR;
 521
 522         }
 523
 524 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
 525
 526         if (ieee80211_is_data(hdr->frame_control) &&
 527             is_multicast_ether_addr(hdr->addr1) &&
 528             mesh_rmc_check(hdr->addr3, msh_h_get(hdr, hdrlen), rx->sdata))
 529                 return RX_DROP_MONITOR;
 530 #undef msh_h_get
 531
 532         return RX_CONTINUE;
 533 }
 534
 535
 536 static ieee80211_rx_result debug_noinline
 537 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
 538 {
 539         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 540
 541         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 542         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 543                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
 544                              rx->sta->last_seq_ctrl[rx->queue] ==
 545                              hdr->seq_ctrl)) {
 546                         if (rx->flags & IEEE80211_RX_RA_MATCH) {
 547                                 rx->local->dot11FrameDuplicateCount++;
 548                                 rx->sta->num_duplicates++;
 549                         }
 550                         return RX_DROP_MONITOR;
 551                 } else
 552                         rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
 553         }
 554
 555         if (unlikely(rx->skb->len < 16)) {
 556                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 557                 return RX_DROP_MONITOR;
 558         }
 559
 560         /* Drop disallowed frame classes based on STA auth/assoc state;
 561          * IEEE 802.11, Chap 5.5.
 562          *
 563          * mac80211 filters only based on association state, i.e. it drops
 564          * Class 3 frames from not associated stations. hostapd sends
 565          * deauth/disassoc frames when needed. In addition, hostapd is
 566          * responsible for filtering on both auth and assoc states.
 567          */
 568
 569         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
 570                 return ieee80211_rx_mesh_check(rx);
 571
 572         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
 573                       ieee80211_is_pspoll(hdr->frame_control)) &&
 574                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
 575                      (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
 576                 if ((!ieee80211_has_fromds(hdr->frame_control) &&
 577                      !ieee80211_has_tods(hdr->frame_control) &&
 578                      ieee80211_is_data(hdr->frame_control)) ||
 579                     !(rx->flags & IEEE80211_RX_RA_MATCH)) {
 580                         /* Drop IBSS frames and frames for other hosts
 581                          * silently. */
 582                         return RX_DROP_MONITOR;
 583                 }
 584
 585                 return RX_DROP_MONITOR;
 586         }
 587
 588         return RX_CONTINUE;
 589 }
 590
 591
 592 static ieee80211_rx_result debug_noinline
 593 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
 594 {
 595         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 596         int keyidx;
 597         int hdrlen;
 598         ieee80211_rx_result result = RX_DROP_UNUSABLE;
 599         struct ieee80211_key *stakey = NULL;
 600         int mmie_keyidx = -1;
 601
 602         /*
 603          * Key selection 101
 604          *
 605          * There are four types of keys:
 606          *  - GTK (group keys)
 607          *  - IGTK (group keys for management frames)
 608          *  - PTK (pairwise keys)
 609          *  - STK (station-to-station pairwise keys)
 610          *
 611          * When selecting a key, we have to distinguish between multicast
 612          * (including broadcast) and unicast frames, the latter can only
 613          * use PTKs and STKs while the former always use GTKs and IGTKs.
 614          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
 615          * unicast frames can also use key indices like GTKs. Hence, if we
 616          * don't have a PTK/STK we check the key index for a WEP key.
 617          *
 618          * Note that in a regular BSS, multicast frames are sent by the
 619          * AP only, associated stations unicast the frame to the AP first
 620          * which then multicasts it on their behalf.
 621          *
 622          * There is also a slight problem in IBSS mode: GTKs are negotiated
 623          * with each station, that is something we don't currently handle.
 624          * The spec seems to expect that one negotiates the same key with
 625          * every station but there's no such requirement; VLANs could be
 626          * possible.
 627          */
 628
 629         /*
 630          * No point in finding a key and decrypting if the frame is neither
 631          * addressed to us nor a multicast frame.
 632          */
 633         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
 634                 return RX_CONTINUE;
 635
 636         if (rx->sta)
 637                 stakey = rcu_dereference(rx->sta->key);
 638
 639         if (!ieee80211_has_protected(hdr->frame_control))
 640                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
 641
 642         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
 643                 rx->key = stakey;
 644                 /* Skip decryption if the frame is not protected. */
 645                 if (!ieee80211_has_protected(hdr->frame_control))
 646                         return RX_CONTINUE;
 647         } else if (mmie_keyidx >= 0) {
 648                 /* Broadcast/multicast robust management frame / BIP */
 649                 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
 650                     (rx->status->flag & RX_FLAG_IV_STRIPPED))
 651                         return RX_CONTINUE;
 652
 653                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
 654                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
 655                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
 656                 rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
 657         } else if (!ieee80211_has_protected(hdr->frame_control)) {
 658                 /*
 659                  * The frame was not protected, so skip decryption. However, we
 660                  * need to set rx->key if there is a key that could have been
 661                  * used so that the frame may be dropped if encryption would
 662                  * have been expected.
 663                  */
 664                 struct ieee80211_key *key = NULL;
 665                 if (ieee80211_is_mgmt(hdr->frame_control) &&
 666                     is_multicast_ether_addr(hdr->addr1) &&
 667                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
 668                         rx->key = key;
 669                 else if ((key = rcu_dereference(rx->sdata->default_key)))
 670                         rx->key = key;
 671                 return RX_CONTINUE;
 672         } else {
 673                 /*
 674                  * The device doesn't give us the IV so we won't be
 675                  * able to look up the key. That's ok though, we
 676                  * don't need to decrypt the frame, we just won't
 677                  * be able to keep statistics accurate.
 678                  * Except for key threshold notifications, should
 679                  * we somehow allow the driver to tell us which key
 680                  * the hardware used if this flag is set?
 681                  */
 682                 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
 683                     (rx->status->flag & RX_FLAG_IV_STRIPPED))
 684                         return RX_CONTINUE;
 685
 686                 hdrlen = ieee80211_hdrlen(hdr->frame_control);
 687
 688                 if (rx->skb->len < 8 + hdrlen)
 689                         return RX_DROP_UNUSABLE; /* TODO: count this? */
 690
 691                 /*
 692                  * no need to call ieee80211_wep_get_keyidx,
 693                  * it verifies a bunch of things we've done already
 694                  */
 695                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
 696
 697                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
 698
 699                 /*
 700                  * RSNA-protected unicast frames should always be sent with
 701                  * pairwise or station-to-station keys, but for WEP we allow
 702                  * using a key index as well.
 703                  */
 704                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
 705                     !is_multicast_ether_addr(hdr->addr1))
 706                         rx->key = NULL;
 707         }
 708
 709         if (rx->key) {
 710                 rx->key->tx_rx_count++;
 711                 /* TODO: add threshold stuff again */
 712         } else {
 713                 return RX_DROP_MONITOR;
 714         }
 715
 716         /* Check for weak IVs if possible */
 717         if (rx->sta && rx->key->conf.alg == ALG_WEP &&
 718             ieee80211_is_data(hdr->frame_control) &&
 719             (!(rx->status->flag & RX_FLAG_IV_STRIPPED) ||
 720              !(rx->status->flag & RX_FLAG_DECRYPTED)) &&
 721             ieee80211_wep_is_weak_iv(rx->skb, rx->key))
 722                 rx->sta->wep_weak_iv_count++;
 723
 724         switch (rx->key->conf.alg) {
 725         case ALG_WEP:
 726                 result = ieee80211_crypto_wep_decrypt(rx);
 727                 break;
 728         case ALG_TKIP:
 729                 result = ieee80211_crypto_tkip_decrypt(rx);
 730                 break;
 731         case ALG_CCMP:
 732                 result = ieee80211_crypto_ccmp_decrypt(rx);
 733                 break;
 734         case ALG_AES_CMAC:
 735                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
 736                 break;
 737         }
 738
 739         /* either the frame has been decrypted or will be dropped */
 740         rx->status->flag |= RX_FLAG_DECRYPTED;
 741
 742         return result;
 743 }
 744
 745 static ieee80211_rx_result debug_noinline
 746 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
 747 {
 748         struct ieee80211_local *local;
 749         struct ieee80211_hdr *hdr;
 750         struct sk_buff *skb;
 751
 752         local = rx->local;
 753         skb = rx->skb;
 754         hdr = (struct ieee80211_hdr *) skb->data;
 755
 756         if (!local->pspolling)
 757                 return RX_CONTINUE;
 758
 759         if (!ieee80211_has_fromds(hdr->frame_control))
 760                 /* this is not from AP */
 761                 return RX_CONTINUE;
 762
 763         if (!ieee80211_is_data(hdr->frame_control))
 764                 return RX_CONTINUE;
 765
 766         if (!ieee80211_has_moredata(hdr->frame_control)) {
 767                 /* AP has no more frames buffered for us */
 768                 local->pspolling = false;
 769                 return RX_CONTINUE;
 770         }
 771
 772         /* more data bit is set, let's request a new frame from the AP */
 773         ieee80211_send_pspoll(local, rx->sdata);
 774
 775         return RX_CONTINUE;
 776 }
 777
 778 static void ap_sta_ps_start(struct sta_info *sta)
 779 {
 780         struct ieee80211_sub_if_data *sdata = sta->sdata;
 781         struct ieee80211_local *local = sdata->local;
 782
 783         atomic_inc(&sdata->bss->num_sta_ps);
 784         set_sta_flags(sta, WLAN_STA_PS_STA);
 785         drv_sta_notify(local, &sdata->vif, STA_NOTIFY_SLEEP, &sta->sta);
 786 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 787         printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
 788                sdata->dev->name, sta->sta.addr, sta->sta.aid);
 789 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 790 }
 791
 792 static void ap_sta_ps_end(struct sta_info *sta)
 793 {
 794         struct ieee80211_sub_if_data *sdata = sta->sdata;
 795
 796         atomic_dec(&sdata->bss->num_sta_ps);
 797
 798         clear_sta_flags(sta, WLAN_STA_PS_STA);
 799
 800 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 801         printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
 802                sdata->dev->name, sta->sta.addr, sta->sta.aid);
 803 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 804
 805         if (test_sta_flags(sta, WLAN_STA_PS_DRIVER)) {
 806 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 807                 printk(KERN_DEBUG "%s: STA %pM aid %d driver-ps-blocked\n",
 808                        sdata->dev->name, sta->sta.addr, sta->sta.aid);
 809 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 810                 return;
 811         }
 812
 813         ieee80211_sta_ps_deliver_wakeup(sta);
 814 }
 815
 816 static ieee80211_rx_result debug_noinline
 817 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
 818 {
 819         struct sta_info *sta = rx->sta;
 820         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 821
 822         if (!sta)
 823                 return RX_CONTINUE;
 824
 825         /*
 826          * Update last_rx only for IBSS packets which are for the current
 827          * BSSID to avoid keeping the current IBSS network alive in cases
 828          * where other STAs start using different BSSID.
 829          */
 830         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
 831                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
 832                                                 NL80211_IFTYPE_ADHOC);
 833                 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0)
 834                         sta->last_rx = jiffies;
 835         } else if (!is_multicast_ether_addr(hdr->addr1)) {
 836                 /*
 837                  * Mesh beacons will update last_rx when if they are found to
 838                  * match the current local configuration when processed.
 839                  */
 840                 sta->last_rx = jiffies;
 841         }
 842
 843         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
 844                 return RX_CONTINUE;
 845
 846         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
 847                 ieee80211_sta_rx_notify(rx->sdata, hdr);
 848
 849         sta->rx_fragments++;
 850         sta->rx_bytes += rx->skb->len;
 851         sta->last_signal = rx->status->signal;
 852         sta->last_noise = rx->status->noise;
 853
 854         /*
 855          * Change STA power saving mode only at the end of a frame
 856          * exchange sequence.
 857          */
 858         if (!ieee80211_has_morefrags(hdr->frame_control) &&
 859             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
 860              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
 861                 if (test_sta_flags(sta, WLAN_STA_PS_STA)) {
 862                         /*
 863                          * Ignore doze->wake transitions that are
 864                          * indicated by non-data frames, the standard
 865                          * is unclear here, but for example going to
 866                          * PS mode and then scanning would cause a
 867                          * doze->wake transition for the probe request,
 868                          * and that is clearly undesirable.
 869                          */
 870                         if (ieee80211_is_data(hdr->frame_control) &&
 871                             !ieee80211_has_pm(hdr->frame_control))
 872                                 ap_sta_ps_end(sta);
 873                 } else {
 874                         if (ieee80211_has_pm(hdr->frame_control))
 875                                 ap_sta_ps_start(sta);
 876                 }
 877         }
 878
 879         /*
 880          * Drop (qos-)data::nullfunc frames silently, since they
 881          * are used only to control station power saving mode.
 882          */
 883         if (ieee80211_is_nullfunc(hdr->frame_control) ||
 884             ieee80211_is_qos_nullfunc(hdr->frame_control)) {
 885                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
 886                 /*
 887                  * Update counter and free packet here to avoid
 888                  * counting this as a dropped packed.
 889                  */
 890                 sta->rx_packets++;
 891                 dev_kfree_skb(rx->skb);
 892                 return RX_QUEUED;
 893         }
 894
 895         return RX_CONTINUE;
 896 } /* ieee80211_rx_h_sta_process */
 897
 898 static inline struct ieee80211_fragment_entry *
 899 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
 900                          unsigned int frag, unsigned int seq, int rx_queue,
 901                          struct sk_buff **skb)
 902 {
 903         struct ieee80211_fragment_entry *entry;
 904         int idx;
 905
 906         idx = sdata->fragment_next;
 907         entry = &sdata->fragments[sdata->fragment_next++];
 908         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
 909                 sdata->fragment_next = 0;
 910
 911         if (!skb_queue_empty(&entry->skb_list)) {
 912 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 913                 struct ieee80211_hdr *hdr =
 914                         (struct ieee80211_hdr *) entry->skb_list.next->data;
 915                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
 916                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
 917                        "addr1=%pM addr2=%pM\n",
 918                        sdata->dev->name, idx,
 919                        jiffies - entry->first_frag_time, entry->seq,
 920                        entry->last_frag, hdr->addr1, hdr->addr2);
 921 #endif
 922                 __skb_queue_purge(&entry->skb_list);
 923         }
 924
 925         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
 926         *skb = NULL;
 927         entry->first_frag_time = jiffies;
 928         entry->seq = seq;
 929         entry->rx_queue = rx_queue;
 930         entry->last_frag = frag;
 931         entry->ccmp = 0;
 932         entry->extra_len = 0;
 933
 934         return entry;
 935 }
 936
 937 static inline struct ieee80211_fragment_entry *
 938 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
 939                           unsigned int frag, unsigned int seq,
 940                           int rx_queue, struct ieee80211_hdr *hdr)
 941 {
 942         struct ieee80211_fragment_entry *entry;
 943         int i, idx;
 944
 945         idx = sdata->fragment_next;
 946         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
 947                 struct ieee80211_hdr *f_hdr;
 948
 949                 idx--;
 950                 if (idx < 0)
 951                         idx = IEEE80211_FRAGMENT_MAX - 1;
 952
 953                 entry = &sdata->fragments[idx];
 954                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
 955                     entry->rx_queue != rx_queue ||
 956                     entry->last_frag + 1 != frag)
 957                         continue;
 958
 959                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
 960
 961                 /*
 962                  * Check ftype and addresses are equal, else check next fragment
 963                  */
 964                 if (((hdr->frame_control ^ f_hdr->frame_control) &
 965                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
 966                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
 967                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
 968                         continue;
 969
 970                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
 971                         __skb_queue_purge(&entry->skb_list);
 972                         continue;
 973                 }
 974                 return entry;
 975         }
 976
 977         return NULL;
 978 }
 979
 980 static ieee80211_rx_result debug_noinline
 981 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
 982 {
 983         struct ieee80211_hdr *hdr;
 984         u16 sc;
 985         __le16 fc;
 986         unsigned int frag, seq;
 987         struct ieee80211_fragment_entry *entry;
 988         struct sk_buff *skb;
 989
 990         hdr = (struct ieee80211_hdr *)rx->skb->data;
 991         fc = hdr->frame_control;
 992         sc = le16_to_cpu(hdr->seq_ctrl);
 993         frag = sc & IEEE80211_SCTL_FRAG;
 994
 995         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
 996                    (rx->skb)->len < 24 ||
 997                    is_multicast_ether_addr(hdr->addr1))) {
 998                 /* not fragmented */
 999                 goto out;
1000         }
1001         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1002
1003         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1004
1005         if (frag == 0) {
1006                 /* This is the first fragment of a new frame. */
1007                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1008                                                  rx->queue, &(rx->skb));
1009                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
1010                     ieee80211_has_protected(fc)) {
1011                         /* Store CCMP PN so that we can verify that the next
1012                          * fragment has a sequential PN value. */
1013                         entry->ccmp = 1;
1014                         memcpy(entry->last_pn,
1015                                rx->key->u.ccmp.rx_pn[rx->queue],
1016                                CCMP_PN_LEN);
1017                 }
1018                 return RX_QUEUED;
1019         }
1020
1021         /* This is a fragment for a frame that should already be pending in
1022          * fragment cache. Add this fragment to the end of the pending entry.
1023          */
1024         entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
1025         if (!entry) {
1026                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1027                 return RX_DROP_MONITOR;
1028         }
1029
1030         /* Verify that MPDUs within one MSDU have sequential PN values.
1031          * (IEEE 802.11i, 8.3.3.4.5) */
1032         if (entry->ccmp) {
1033                 int i;
1034                 u8 pn[CCMP_PN_LEN], *rpn;
1035                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
1036                         return RX_DROP_UNUSABLE;
1037                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1038                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1039                         pn[i]++;
1040                         if (pn[i])
1041                                 break;
1042                 }
1043                 rpn = rx->key->u.ccmp.rx_pn[rx->queue];
1044                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1045                         return RX_DROP_UNUSABLE;
1046                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1047         }
1048
1049         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1050         __skb_queue_tail(&entry->skb_list, rx->skb);
1051         entry->last_frag = frag;
1052         entry->extra_len += rx->skb->len;
1053         if (ieee80211_has_morefrags(fc)) {
1054                 rx->skb = NULL;
1055                 return RX_QUEUED;
1056         }
1057
1058         rx->skb = __skb_dequeue(&entry->skb_list);
1059         if (skb_tailroom(rx->skb) < entry->extra_len) {
1060                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1061                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1062                                               GFP_ATOMIC))) {
1063                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1064                         __skb_queue_purge(&entry->skb_list);
1065                         return RX_DROP_UNUSABLE;
1066                 }
1067         }
1068         while ((skb = __skb_dequeue(&entry->skb_list))) {
1069                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1070                 dev_kfree_skb(skb);
1071         }
1072
1073         /* Complete frame has been reassembled - process it now */
1074         rx->flags |= IEEE80211_RX_FRAGMENTED;
1075
1076  out:
1077         if (rx->sta)
1078                 rx->sta->rx_packets++;
1079         if (is_multicast_ether_addr(hdr->addr1))
1080                 rx->local->dot11MulticastReceivedFrameCount++;
1081         else
1082                 ieee80211_led_rx(rx->local);
1083         return RX_CONTINUE;
1084 }
1085
1086 static ieee80211_rx_result debug_noinline
1087 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
1088 {
1089         struct ieee80211_sub_if_data *sdata = rx->sdata;
1090         __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
1091
1092         if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
1093                    !(rx->flags & IEEE80211_RX_RA_MATCH)))
1094                 return RX_CONTINUE;
1095
1096         if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1097             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1098                 return RX_DROP_UNUSABLE;
1099
1100         if (!test_sta_flags(rx->sta, WLAN_STA_PS_DRIVER))
1101                 ieee80211_sta_ps_deliver_poll_response(rx->sta);
1102         else
1103                 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1104
1105         /* Free PS Poll skb here instead of returning RX_DROP that would
1106          * count as an dropped frame. */
1107         dev_kfree_skb(rx->skb);
1108
1109         return RX_QUEUED;
1110 }
1111
1112 static ieee80211_rx_result debug_noinline
1113 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1114 {
1115         u8 *data = rx->skb->data;
1116         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1117
1118         if (!ieee80211_is_data_qos(hdr->frame_control))
1119                 return RX_CONTINUE;
1120
1121         /* remove the qos control field, update frame type and meta-data */
1122         memmove(data + IEEE80211_QOS_CTL_LEN, data,
1123                 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1124         hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1125         /* change frame type to non QOS */
1126         hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1127
1128         return RX_CONTINUE;
1129 }
1130
1131 static int
1132 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1133 {
1134         if (unlikely(!rx->sta ||
1135             !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1136                 return -EACCES;
1137
1138         return 0;
1139 }
1140
1141 static int
1142 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1143 {
1144         /*
1145          * Pass through unencrypted frames if the hardware has
1146          * decrypted them already.
1147          */
1148         if (rx->status->flag & RX_FLAG_DECRYPTED)
1149                 return 0;
1150
1151         /* Drop unencrypted frames if key is set. */
1152         if (unlikely(!ieee80211_has_protected(fc) &&
1153                      !ieee80211_is_nullfunc(fc) &&
1154                      ieee80211_is_data(fc) &&
1155                      (rx->key || rx->sdata->drop_unencrypted)))
1156                 return -EACCES;
1157         if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) {
1158                 if (unlikely(ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1159                              rx->key))
1160                         return -EACCES;
1161                 /* BIP does not use Protected field, so need to check MMIE */
1162                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb)
1163                              && ieee80211_get_mmie_keyidx(rx->skb) < 0 &&
1164                              rx->key))
1165                         return -EACCES;
1166                 /*
1167                  * When using MFP, Action frames are not allowed prior to
1168                  * having configured keys.
1169                  */
1170                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1171                              ieee80211_is_robust_mgmt_frame(
1172                                      (struct ieee80211_hdr *) rx->skb->data)))
1173                         return -EACCES;
1174         }
1175
1176         return 0;
1177 }
1178
1179 static int
1180 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1181 {
1182         struct net_device *dev = rx->dev;
1183         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1184         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1185
1186         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->use_4addr &&
1187             ieee80211_has_a4(hdr->frame_control))
1188                 return -1;
1189         if (sdata->use_4addr && is_multicast_ether_addr(hdr->addr1))
1190                 return -1;
1191
1192         return ieee80211_data_to_8023(rx->skb, dev->dev_addr, sdata->vif.type);
1193 }
1194
1195 /*
1196  * requires that rx->skb is a frame with ethernet header
1197  */
1198 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1199 {
1200         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1201                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1202         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1203
1204         /*
1205          * Allow EAPOL frames to us/the PAE group address regardless
1206          * of whether the frame was encrypted or not.
1207          */
1208         if (ehdr->h_proto == htons(ETH_P_PAE) &&
1209             (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
1210              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1211                 return true;
1212
1213         if (ieee80211_802_1x_port_control(rx) ||
1214             ieee80211_drop_unencrypted(rx, fc))
1215                 return false;
1216
1217         return true;
1218 }
1219
1220 /*
1221  * requires that rx->skb is a frame with ethernet header
1222  */
1223 static void
1224 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1225 {
1226         struct net_device *dev = rx->dev;
1227         struct ieee80211_local *local = rx->local;
1228         struct sk_buff *skb, *xmit_skb;
1229         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1230         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1231         struct sta_info *dsta;
1232
1233         skb = rx->skb;
1234         xmit_skb = NULL;
1235
1236         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1237              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1238             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1239             (rx->flags & IEEE80211_RX_RA_MATCH) && !rx->sdata->use_4addr) {
1240                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1241                         /*
1242                          * send multicast frames both to higher layers in
1243                          * local net stack and back to the wireless medium
1244                          */
1245                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1246                         if (!xmit_skb && net_ratelimit())
1247                                 printk(KERN_DEBUG "%s: failed to clone "
1248                                        "multicast frame\n", dev->name);
1249                 } else {
1250                         dsta = sta_info_get(local, skb->data);
1251                         if (dsta && dsta->sdata->dev == dev) {
1252                                 /*
1253                                  * The destination station is associated to
1254                                  * this AP (in this VLAN), so send the frame
1255                                  * directly to it and do not pass it to local
1256                                  * net stack.
1257                                  */
1258                                 xmit_skb = skb;
1259                                 skb = NULL;
1260                         }
1261                 }
1262         }
1263
1264         if (skb) {
1265                 int align __maybe_unused;
1266
1267 #if defined(CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT) || !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
1268                 /*
1269                  * 'align' will only take the values 0 or 2 here
1270                  * since all frames are required to be aligned
1271                  * to 2-byte boundaries when being passed to
1272                  * mac80211. That also explains the __skb_push()
1273                  * below.
1274                  */
1275                 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1276                 if (align) {
1277                         if (WARN_ON(skb_headroom(skb) < 3)) {
1278                                 dev_kfree_skb(skb);
1279                                 skb = NULL;
1280                         } else {
1281                                 u8 *data = skb->data;
1282                                 size_t len = skb_headlen(skb);
1283                                 skb->data -= align;
1284                                 memmove(skb->data, data, len);
1285                                 skb_set_tail_pointer(skb, len);
1286                         }
1287                 }
1288 #endif
1289
1290                 if (skb) {
1291                         /* deliver to local stack */
1292                         skb->protocol = eth_type_trans(skb, dev);
1293                         memset(skb->cb, 0, sizeof(skb->cb));
1294                         netif_rx(skb);
1295                 }
1296         }
1297
1298         if (xmit_skb) {
1299                 /* send to wireless media */
1300                 xmit_skb->protocol = htons(ETH_P_802_3);
1301                 skb_reset_network_header(xmit_skb);
1302                 skb_reset_mac_header(xmit_skb);
1303                 dev_queue_xmit(xmit_skb);
1304         }
1305 }
1306
1307 static ieee80211_rx_result debug_noinline
1308 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1309 {
1310         struct net_device *dev = rx->dev;
1311         struct ieee80211_local *local = rx->local;
1312         u16 ethertype;
1313         u8 *payload;
1314         struct sk_buff *skb = rx->skb, *frame = NULL;
1315         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1316         __le16 fc = hdr->frame_control;
1317         const struct ethhdr *eth;
1318         int remaining, err;
1319         u8 dst[ETH_ALEN];
1320         u8 src[ETH_ALEN];
1321
1322         if (unlikely(!ieee80211_is_data(fc)))
1323                 return RX_CONTINUE;
1324
1325         if (unlikely(!ieee80211_is_data_present(fc)))
1326                 return RX_DROP_MONITOR;
1327
1328         if (!(rx->flags & IEEE80211_RX_AMSDU))
1329                 return RX_CONTINUE;
1330
1331         err = __ieee80211_data_to_8023(rx);
1332         if (unlikely(err))
1333                 return RX_DROP_UNUSABLE;
1334
1335         skb->dev = dev;
1336
1337         dev->stats.rx_packets++;
1338         dev->stats.rx_bytes += skb->len;
1339
1340         /* skip the wrapping header */
1341         eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
1342         if (!eth)
1343                 return RX_DROP_UNUSABLE;
1344
1345         while (skb != frame) {
1346                 u8 padding;
1347                 __be16 len = eth->h_proto;
1348                 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
1349
1350                 remaining = skb->len;
1351                 memcpy(dst, eth->h_dest, ETH_ALEN);
1352                 memcpy(src, eth->h_source, ETH_ALEN);
1353
1354                 padding = ((4 - subframe_len) & 0x3);
1355                 /* the last MSDU has no padding */
1356                 if (subframe_len > remaining)
1357                         return RX_DROP_UNUSABLE;
1358
1359                 skb_pull(skb, sizeof(struct ethhdr));
1360                 /* if last subframe reuse skb */
1361                 if (remaining <= subframe_len + padding)
1362                         frame = skb;
1363                 else {
1364                         /*
1365                          * Allocate and reserve two bytes more for payload
1366                          * alignment since sizeof(struct ethhdr) is 14.
1367                          */
1368                         frame = dev_alloc_skb(
1369                                 ALIGN(local->hw.extra_tx_headroom, 4) +
1370                                 subframe_len + 2);
1371
1372                         if (frame == NULL)
1373                                 return RX_DROP_UNUSABLE;
1374
1375                         skb_reserve(frame,
1376                                     ALIGN(local->hw.extra_tx_headroom, 4) +
1377                                     sizeof(struct ethhdr) + 2);
1378                         memcpy(skb_put(frame, ntohs(len)), skb->data,
1379                                 ntohs(len));
1380
1381                         eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
1382                                                         padding);
1383                         if (!eth) {
1384                                 dev_kfree_skb(frame);
1385                                 return RX_DROP_UNUSABLE;
1386                         }
1387                 }
1388
1389                 skb_reset_network_header(frame);
1390                 frame->dev = dev;
1391                 frame->priority = skb->priority;
1392                 rx->skb = frame;
1393
1394                 payload = frame->data;
1395                 ethertype = (payload[6] << 8) | payload[7];
1396
1397                 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1398                             ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1399                            compare_ether_addr(payload,
1400                                               bridge_tunnel_header) == 0)) {
1401                         /* remove RFC1042 or Bridge-Tunnel
1402                          * encapsulation and replace EtherType */
1403                         skb_pull(frame, 6);
1404                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1405                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1406                 } else {
1407                         memcpy(skb_push(frame, sizeof(__be16)),
1408                                &len, sizeof(__be16));
1409                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1410                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1411                 }
1412
1413                 if (!ieee80211_frame_allowed(rx, fc)) {
1414                         if (skb == frame) /* last frame */
1415                                 return RX_DROP_UNUSABLE;
1416                         dev_kfree_skb(frame);
1417                         continue;
1418                 }
1419
1420                 ieee80211_deliver_skb(rx);
1421         }
1422
1423         return RX_QUEUED;
1424 }
1425
1426 #ifdef CONFIG_MAC80211_MESH
1427 static ieee80211_rx_result
1428 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1429 {
1430         struct ieee80211_hdr *hdr;
1431         struct ieee80211s_hdr *mesh_hdr;
1432         unsigned int hdrlen;
1433         struct sk_buff *skb = rx->skb, *fwd_skb;
1434         struct ieee80211_local *local = rx->local;
1435         struct ieee80211_sub_if_data *sdata;
1436
1437         hdr = (struct ieee80211_hdr *) skb->data;
1438         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1439         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1440         sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1441
1442         if (!ieee80211_is_data(hdr->frame_control))
1443                 return RX_CONTINUE;
1444
1445         if (!mesh_hdr->ttl)
1446                 /* illegal frame */
1447                 return RX_DROP_MONITOR;
1448
1449         if (mesh_hdr->flags & MESH_FLAGS_AE) {
1450                 struct mesh_path *mppath;
1451                 char *proxied_addr;
1452                 char *mpp_addr;
1453
1454                 if (is_multicast_ether_addr(hdr->addr1)) {
1455                         mpp_addr = hdr->addr3;
1456                         proxied_addr = mesh_hdr->eaddr1;
1457                 } else {
1458                         mpp_addr = hdr->addr4;
1459                         proxied_addr = mesh_hdr->eaddr2;
1460                 }
1461
1462                 rcu_read_lock();
1463                 mppath = mpp_path_lookup(proxied_addr, sdata);
1464                 if (!mppath) {
1465                         mpp_path_add(proxied_addr, mpp_addr, sdata);
1466                 } else {
1467                         spin_lock_bh(&mppath->state_lock);
1468                         mppath->exp_time = jiffies;
1469                         if (compare_ether_addr(mppath->mpp, mpp_addr) != 0)
1470                                 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
1471                         spin_unlock_bh(&mppath->state_lock);
1472                 }
1473                 rcu_read_unlock();
1474         }
1475
1476         /* Frame has reached destination.  Don't forward */
1477         if (!is_multicast_ether_addr(hdr->addr1) &&
1478                         compare_ether_addr(rx->dev->dev_addr, hdr->addr3) == 0)
1479                 return RX_CONTINUE;
1480
1481         mesh_hdr->ttl--;
1482
1483         if (rx->flags & IEEE80211_RX_RA_MATCH) {
1484                 if (!mesh_hdr->ttl)
1485                         IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1486                                                      dropped_frames_ttl);
1487                 else {
1488                         struct ieee80211_hdr *fwd_hdr;
1489                         struct ieee80211_tx_info *info;
1490
1491                         fwd_skb = skb_copy(skb, GFP_ATOMIC);
1492
1493                         if (!fwd_skb && net_ratelimit())
1494                                 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1495                                                    rx->dev->name);
1496
1497                         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1498                         memcpy(fwd_hdr->addr2, rx->dev->dev_addr, ETH_ALEN);
1499                         info = IEEE80211_SKB_CB(fwd_skb);
1500                         memset(info, 0, sizeof(*info));
1501                         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1502                         info->control.vif = &rx->sdata->vif;
1503                         ieee80211_select_queue(local, fwd_skb);
1504                         if (is_multicast_ether_addr(fwd_hdr->addr1))
1505                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1506                                                                 fwded_mcast);
1507                         else {
1508                                 int err;
1509                                 /*
1510                                  * Save TA to addr1 to send TA a path error if a
1511                                  * suitable next hop is not found
1512                                  */
1513                                 memcpy(fwd_hdr->addr1, fwd_hdr->addr2,
1514                                                 ETH_ALEN);
1515                                 err = mesh_nexthop_lookup(fwd_skb, sdata);
1516                                 /* Failed to immediately resolve next hop:
1517                                  * fwded frame was dropped or will be added
1518                                  * later to the pending skb queue.  */
1519                                 if (err)
1520                                         return RX_DROP_MONITOR;
1521
1522                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1523                                                                 fwded_unicast);
1524                         }
1525                         IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1526                                                      fwded_frames);
1527                         ieee80211_add_pending_skb(local, fwd_skb);
1528                 }
1529         }
1530
1531         if (is_multicast_ether_addr(hdr->addr1) ||
1532             rx->dev->flags & IFF_PROMISC)
1533                 return RX_CONTINUE;
1534         else
1535                 return RX_DROP_MONITOR;
1536 }
1537 #endif
1538
1539 static ieee80211_rx_result debug_noinline
1540 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1541 {
1542         struct net_device *dev = rx->dev;
1543         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1544         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1545         __le16 fc = hdr->frame_control;
1546         int err;
1547
1548         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1549                 return RX_CONTINUE;
1550
1551         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1552                 return RX_DROP_MONITOR;
1553
1554         /*
1555          * Allow the cooked monitor interface of an AP to see 4-addr frames so
1556          * that a 4-addr station can be detected and moved into a separate VLAN
1557          */
1558         if (ieee80211_has_a4(hdr->frame_control) &&
1559             sdata->vif.type == NL80211_IFTYPE_AP)
1560                 return RX_DROP_MONITOR;
1561
1562         err = __ieee80211_data_to_8023(rx);
1563         if (unlikely(err))
1564                 return RX_DROP_UNUSABLE;
1565
1566         if (!ieee80211_frame_allowed(rx, fc))
1567                 return RX_DROP_MONITOR;
1568
1569         rx->skb->dev = dev;
1570
1571         dev->stats.rx_packets++;
1572         dev->stats.rx_bytes += rx->skb->len;
1573
1574         ieee80211_deliver_skb(rx);
1575
1576         return RX_QUEUED;
1577 }
1578
1579 static ieee80211_rx_result debug_noinline
1580 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
1581 {
1582         struct ieee80211_local *local = rx->local;
1583         struct ieee80211_hw *hw = &local->hw;
1584         struct sk_buff *skb = rx->skb;
1585         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1586         struct tid_ampdu_rx *tid_agg_rx;
1587         u16 start_seq_num;
1588         u16 tid;
1589
1590         if (likely(!ieee80211_is_ctl(bar->frame_control)))
1591                 return RX_CONTINUE;
1592
1593         if (ieee80211_is_back_req(bar->frame_control)) {
1594                 if (!rx->sta)
1595                         return RX_CONTINUE;
1596                 tid = le16_to_cpu(bar->control) >> 12;
1597                 if (rx->sta->ampdu_mlme.tid_state_rx[tid]
1598                                         != HT_AGG_STATE_OPERATIONAL)
1599                         return RX_CONTINUE;
1600                 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid];
1601
1602                 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1603
1604                 /* reset session timer */
1605                 if (tid_agg_rx->timeout)
1606                         mod_timer(&tid_agg_rx->session_timer,
1607                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
1608
1609                 /* manage reordering buffer according to requested */
1610                 /* sequence number */
1611                 rcu_read_lock();
1612                 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL,
1613                                                  start_seq_num, 1);
1614                 rcu_read_unlock();
1615                 return RX_DROP_UNUSABLE;
1616         }
1617
1618         return RX_CONTINUE;
1619 }
1620
1621 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
1622                                            struct ieee80211_mgmt *mgmt,
1623                                            size_t len)
1624 {
1625         struct ieee80211_local *local = sdata->local;
1626         struct sk_buff *skb;
1627         struct ieee80211_mgmt *resp;
1628
1629         if (compare_ether_addr(mgmt->da, sdata->dev->dev_addr) != 0) {
1630                 /* Not to own unicast address */
1631                 return;
1632         }
1633
1634         if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
1635             compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
1636                 /* Not from the current AP or not associated yet. */
1637                 return;
1638         }
1639
1640         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
1641                 /* Too short SA Query request frame */
1642                 return;
1643         }
1644
1645         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
1646         if (skb == NULL)
1647                 return;
1648
1649         skb_reserve(skb, local->hw.extra_tx_headroom);
1650         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
1651         memset(resp, 0, 24);
1652         memcpy(resp->da, mgmt->sa, ETH_ALEN);
1653         memcpy(resp->sa, sdata->dev->dev_addr, ETH_ALEN);
1654         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
1655         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1656                                           IEEE80211_STYPE_ACTION);
1657         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
1658         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
1659         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
1660         memcpy(resp->u.action.u.sa_query.trans_id,
1661                mgmt->u.action.u.sa_query.trans_id,
1662                WLAN_SA_QUERY_TR_ID_LEN);
1663
1664         ieee80211_tx_skb(sdata, skb, 1);
1665 }
1666
1667 static ieee80211_rx_result debug_noinline
1668 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
1669 {
1670         struct ieee80211_local *local = rx->local;
1671         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1672         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1673         int len = rx->skb->len;
1674
1675         if (!ieee80211_is_action(mgmt->frame_control))
1676                 return RX_CONTINUE;
1677
1678         if (!rx->sta)
1679                 return RX_DROP_MONITOR;
1680
1681         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1682                 return RX_DROP_MONITOR;
1683
1684         if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
1685                 return RX_DROP_MONITOR;
1686
1687         /* all categories we currently handle have action_code */
1688         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
1689                 return RX_DROP_MONITOR;
1690
1691         switch (mgmt->u.action.category) {
1692         case WLAN_CATEGORY_BACK:
1693                 /*
1694                  * The aggregation code is not prepared to handle
1695                  * anything but STA/AP due to the BSSID handling;
1696                  * IBSS could work in the code but isn't supported
1697                  * by drivers or the standard.
1698                  */
1699                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
1700                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
1701                     sdata->vif.type != NL80211_IFTYPE_AP)
1702                         return RX_DROP_MONITOR;
1703
1704                 switch (mgmt->u.action.u.addba_req.action_code) {
1705                 case WLAN_ACTION_ADDBA_REQ:
1706                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1707                                    sizeof(mgmt->u.action.u.addba_req)))
1708                                 return RX_DROP_MONITOR;
1709                         ieee80211_process_addba_request(local, rx->sta, mgmt, len);
1710                         break;
1711                 case WLAN_ACTION_ADDBA_RESP:
1712                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1713                                    sizeof(mgmt->u.action.u.addba_resp)))
1714                                 return RX_DROP_MONITOR;
1715                         ieee80211_process_addba_resp(local, rx->sta, mgmt, len);
1716                         break;
1717                 case WLAN_ACTION_DELBA:
1718                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1719                                    sizeof(mgmt->u.action.u.delba)))
1720                                 return RX_DROP_MONITOR;
1721                         ieee80211_process_delba(sdata, rx->sta, mgmt, len);
1722                         break;
1723                 }
1724                 break;
1725         case WLAN_CATEGORY_SPECTRUM_MGMT:
1726                 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
1727                         return RX_DROP_MONITOR;
1728
1729                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
1730                         return RX_DROP_MONITOR;
1731
1732                 switch (mgmt->u.action.u.measurement.action_code) {
1733                 case WLAN_ACTION_SPCT_MSR_REQ:
1734                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1735                                    sizeof(mgmt->u.action.u.measurement)))
1736                                 return RX_DROP_MONITOR;
1737                         ieee80211_process_measurement_req(sdata, mgmt, len);
1738                         break;
1739                 case WLAN_ACTION_SPCT_CHL_SWITCH:
1740                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1741                                    sizeof(mgmt->u.action.u.chan_switch)))
1742                                 return RX_DROP_MONITOR;
1743
1744                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
1745                                 return RX_DROP_MONITOR;
1746
1747                         if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
1748                                 return RX_DROP_MONITOR;
1749
1750                         return ieee80211_sta_rx_mgmt(sdata, rx->skb);
1751                 }
1752                 break;
1753         case WLAN_CATEGORY_SA_QUERY:
1754                 if (len < (IEEE80211_MIN_ACTION_SIZE +
1755                            sizeof(mgmt->u.action.u.sa_query)))
1756                         return RX_DROP_MONITOR;
1757                 switch (mgmt->u.action.u.sa_query.action) {
1758                 case WLAN_ACTION_SA_QUERY_REQUEST:
1759                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
1760                                 return RX_DROP_MONITOR;
1761                         ieee80211_process_sa_query_req(sdata, mgmt, len);
1762                         break;
1763                 case WLAN_ACTION_SA_QUERY_RESPONSE:
1764                         /*
1765                          * SA Query response is currently only used in AP mode
1766                          * and it is processed in user space.
1767                          */
1768                         return RX_CONTINUE;
1769                 }
1770                 break;
1771         default:
1772                 return RX_CONTINUE;
1773         }
1774
1775         rx->sta->rx_packets++;
1776         dev_kfree_skb(rx->skb);
1777         return RX_QUEUED;
1778 }
1779
1780 static ieee80211_rx_result debug_noinline
1781 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
1782 {
1783         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1784         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1785
1786         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1787                 return RX_DROP_MONITOR;
1788
1789         if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
1790                 return RX_DROP_MONITOR;
1791
1792         if (ieee80211_vif_is_mesh(&sdata->vif))
1793                 return ieee80211_mesh_rx_mgmt(sdata, rx->skb);
1794
1795         if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
1796                 return ieee80211_ibss_rx_mgmt(sdata, rx->skb);
1797
1798         if (sdata->vif.type == NL80211_IFTYPE_STATION)
1799                 return ieee80211_sta_rx_mgmt(sdata, rx->skb);
1800
1801         return RX_DROP_MONITOR;
1802 }
1803
1804 static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr,
1805                                             struct ieee80211_rx_data *rx)
1806 {
1807         int keyidx;
1808         unsigned int hdrlen;
1809
1810         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1811         if (rx->skb->len >= hdrlen + 4)
1812                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1813         else
1814                 keyidx = -1;
1815
1816         if (!rx->sta) {
1817                 /*
1818                  * Some hardware seem to generate incorrect Michael MIC
1819                  * reports; ignore them to avoid triggering countermeasures.
1820                  */
1821                 return;
1822         }
1823
1824         if (!ieee80211_has_protected(hdr->frame_control))
1825                 return;
1826
1827         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
1828                 /*
1829                  * APs with pairwise keys should never receive Michael MIC
1830                  * errors for non-zero keyidx because these are reserved for
1831                  * group keys and only the AP is sending real multicast
1832                  * frames in the BSS.
1833                  */
1834                 return;
1835         }
1836
1837         if (!ieee80211_is_data(hdr->frame_control) &&
1838             !ieee80211_is_auth(hdr->frame_control))
1839                 return;
1840
1841         mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL,
1842                                         GFP_ATOMIC);
1843 }
1844
1845 /* TODO: use IEEE80211_RX_FRAGMENTED */
1846 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx)
1847 {
1848         struct ieee80211_sub_if_data *sdata;
1849         struct ieee80211_local *local = rx->local;
1850         struct ieee80211_rtap_hdr {
1851                 struct ieee80211_radiotap_header hdr;
1852                 u8 flags;
1853                 u8 rate;
1854                 __le16 chan_freq;
1855                 __le16 chan_flags;
1856         } __attribute__ ((packed)) *rthdr;
1857         struct sk_buff *skb = rx->skb, *skb2;
1858         struct net_device *prev_dev = NULL;
1859         struct ieee80211_rx_status *status = rx->status;
1860
1861         if (rx->flags & IEEE80211_RX_CMNTR_REPORTED)
1862                 goto out_free_skb;
1863
1864         if (skb_headroom(skb) < sizeof(*rthdr) &&
1865             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
1866                 goto out_free_skb;
1867
1868         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
1869         memset(rthdr, 0, sizeof(*rthdr));
1870         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
1871         rthdr->hdr.it_present =
1872                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
1873                             (1 << IEEE80211_RADIOTAP_RATE) |
1874                             (1 << IEEE80211_RADIOTAP_CHANNEL));
1875
1876         rthdr->rate = rx->rate->bitrate / 5;
1877         rthdr->chan_freq = cpu_to_le16(status->freq);
1878
1879         if (status->band == IEEE80211_BAND_5GHZ)
1880                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
1881                                                 IEEE80211_CHAN_5GHZ);
1882         else
1883                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
1884                                                 IEEE80211_CHAN_2GHZ);
1885
1886         skb_set_mac_header(skb, 0);
1887         skb->ip_summed = CHECKSUM_UNNECESSARY;
1888         skb->pkt_type = PACKET_OTHERHOST;
1889         skb->protocol = htons(ETH_P_802_2);
1890
1891         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1892                 if (!netif_running(sdata->dev))
1893                         continue;
1894
1895                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
1896                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
1897                         continue;
1898
1899                 if (prev_dev) {
1900                         skb2 = skb_clone(skb, GFP_ATOMIC);
1901                         if (skb2) {
1902                                 skb2->dev = prev_dev;
1903                                 netif_rx(skb2);
1904                         }
1905                 }
1906
1907                 prev_dev = sdata->dev;
1908                 sdata->dev->stats.rx_packets++;
1909                 sdata->dev->stats.rx_bytes += skb->len;
1910         }
1911
1912         if (prev_dev) {
1913                 skb->dev = prev_dev;
1914                 netif_rx(skb);
1915                 skb = NULL;
1916         } else
1917                 goto out_free_skb;
1918
1919         rx->flags |= IEEE80211_RX_CMNTR_REPORTED;
1920         return;
1921
1922  out_free_skb:
1923         dev_kfree_skb(skb);
1924 }
1925
1926
1927 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
1928                                          struct ieee80211_rx_data *rx,
1929                                          struct sk_buff *skb)
1930 {
1931         ieee80211_rx_result res = RX_DROP_MONITOR;
1932
1933         rx->skb = skb;
1934         rx->sdata = sdata;
1935         rx->dev = sdata->dev;
1936
1937 #define CALL_RXH(rxh)                   \
1938         do {                            \
1939                 res = rxh(rx);          \
1940                 if (res != RX_CONTINUE) \
1941                         goto rxh_done;  \
1942         } while (0);
1943
1944         CALL_RXH(ieee80211_rx_h_passive_scan)
1945         CALL_RXH(ieee80211_rx_h_check)
1946         CALL_RXH(ieee80211_rx_h_decrypt)
1947         CALL_RXH(ieee80211_rx_h_check_more_data)
1948         CALL_RXH(ieee80211_rx_h_sta_process)
1949         CALL_RXH(ieee80211_rx_h_defragment)
1950         CALL_RXH(ieee80211_rx_h_ps_poll)
1951         CALL_RXH(ieee80211_rx_h_michael_mic_verify)
1952         /* must be after MMIC verify so header is counted in MPDU mic */
1953         CALL_RXH(ieee80211_rx_h_remove_qos_control)
1954         CALL_RXH(ieee80211_rx_h_amsdu)
1955 #ifdef CONFIG_MAC80211_MESH
1956         if (ieee80211_vif_is_mesh(&sdata->vif))
1957                 CALL_RXH(ieee80211_rx_h_mesh_fwding);
1958 #endif
1959         CALL_RXH(ieee80211_rx_h_data)
1960         CALL_RXH(ieee80211_rx_h_ctrl)
1961         CALL_RXH(ieee80211_rx_h_action)
1962         CALL_RXH(ieee80211_rx_h_mgmt)
1963
1964 #undef CALL_RXH
1965
1966  rxh_done:
1967         switch (res) {
1968         case RX_DROP_MONITOR:
1969                 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
1970                 if (rx->sta)
1971                         rx->sta->rx_dropped++;
1972                 /* fall through */
1973         case RX_CONTINUE:
1974                 ieee80211_rx_cooked_monitor(rx);
1975                 break;
1976         case RX_DROP_UNUSABLE:
1977                 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
1978                 if (rx->sta)
1979                         rx->sta->rx_dropped++;
1980                 dev_kfree_skb(rx->skb);
1981                 break;
1982         case RX_QUEUED:
1983                 I802_DEBUG_INC(sdata->local->rx_handlers_queued);
1984                 break;
1985         }
1986 }
1987
1988 /* main receive path */
1989
1990 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
1991                                 struct ieee80211_rx_data *rx,
1992                                 struct ieee80211_hdr *hdr)
1993 {
1994         u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, sdata->vif.type);
1995         int multicast = is_multicast_ether_addr(hdr->addr1);
1996
1997         switch (sdata->vif.type) {
1998         case NL80211_IFTYPE_STATION:
1999                 if (!bssid && !sdata->use_4addr)
2000                         return 0;
2001                 if (!multicast &&
2002                     compare_ether_addr(sdata->dev->dev_addr, hdr->addr1) != 0) {
2003                         if (!(sdata->dev->flags & IFF_PROMISC))
2004                                 return 0;
2005                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2006                 }
2007                 break;
2008         case NL80211_IFTYPE_ADHOC:
2009                 if (!bssid)
2010                         return 0;
2011                 if (ieee80211_is_beacon(hdr->frame_control)) {
2012                         return 1;
2013                 }
2014                 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2015                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2016                                 return 0;
2017                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2018                 } else if (!multicast &&
2019                            compare_ether_addr(sdata->dev->dev_addr,
2020                                               hdr->addr1) != 0) {
2021                         if (!(sdata->dev->flags & IFF_PROMISC))
2022                                 return 0;
2023                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2024                 } else if (!rx->sta) {
2025                         int rate_idx;
2026                         if (rx->status->flag & RX_FLAG_HT)
2027                                 rate_idx = 0; /* TODO: HT rates */
2028                         else
2029                                 rate_idx = rx->status->rate_idx;
2030                         rx->sta = ieee80211_ibss_add_sta(sdata, bssid, hdr->addr2,
2031                                 BIT(rate_idx));
2032                 }
2033                 break;
2034         case NL80211_IFTYPE_MESH_POINT:
2035                 if (!multicast &&
2036                     compare_ether_addr(sdata->dev->dev_addr,
2037                                        hdr->addr1) != 0) {
2038                         if (!(sdata->dev->flags & IFF_PROMISC))
2039                                 return 0;
2040
2041                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2042                 }
2043                 break;
2044         case NL80211_IFTYPE_AP_VLAN:
2045         case NL80211_IFTYPE_AP:
2046                 if (!bssid) {
2047                         if (compare_ether_addr(sdata->dev->dev_addr,
2048                                                hdr->addr1))
2049                                 return 0;
2050                 } else if (!ieee80211_bssid_match(bssid,
2051                                         sdata->dev->dev_addr)) {
2052                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2053                                 return 0;
2054                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2055                 }
2056                 break;
2057         case NL80211_IFTYPE_WDS:
2058                 if (bssid || !ieee80211_is_data(hdr->frame_control))
2059                         return 0;
2060                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2061                         return 0;
2062                 break;
2063         case NL80211_IFTYPE_MONITOR:
2064         case NL80211_IFTYPE_UNSPECIFIED:
2065         case __NL80211_IFTYPE_AFTER_LAST:
2066                 /* should never get here */
2067                 WARN_ON(1);
2068                 break;
2069         }
2070
2071         return 1;
2072 }
2073
2074 /*
2075  * This is the actual Rx frames handler. as it blongs to Rx path it must
2076  * be called with rcu_read_lock protection.
2077  */
2078 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2079                                          struct sk_buff *skb,
2080                                          struct ieee80211_rate *rate)
2081 {
2082         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2083         struct ieee80211_local *local = hw_to_local(hw);
2084         struct ieee80211_sub_if_data *sdata;
2085         struct ieee80211_hdr *hdr;
2086         struct ieee80211_rx_data rx;
2087         int prepares;
2088         struct ieee80211_sub_if_data *prev = NULL;
2089         struct sk_buff *skb_new;
2090
2091         hdr = (struct ieee80211_hdr *)skb->data;
2092         memset(&rx, 0, sizeof(rx));
2093         rx.skb = skb;
2094         rx.local = local;
2095         rx.status = status;
2096         rx.rate = rate;
2097
2098         if (ieee80211_is_data(hdr->frame_control) || ieee80211_is_mgmt(hdr->frame_control))
2099                 local->dot11ReceivedFragmentCount++;
2100
2101         if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) ||
2102                      test_bit(SCAN_OFF_CHANNEL, &local->scanning)))
2103                 rx.flags |= IEEE80211_RX_IN_SCAN;
2104
2105         ieee80211_parse_qos(&rx);
2106         ieee80211_verify_alignment(&rx);
2107
2108         rx.sta = sta_info_get(local, hdr->addr2);
2109         if (rx.sta) {
2110                 rx.sdata = rx.sta->sdata;
2111                 rx.dev = rx.sta->sdata->dev;
2112         }
2113
2114         if (rx.sdata && ieee80211_is_data(hdr->frame_control)) {
2115                 rx.flags |= IEEE80211_RX_RA_MATCH;
2116                 prepares = prepare_for_handlers(rx.sdata, &rx, hdr);
2117                 if (prepares) {
2118                         if (status->flag & RX_FLAG_MMIC_ERROR) {
2119                                 if (rx.flags & IEEE80211_RX_RA_MATCH)
2120                                         ieee80211_rx_michael_mic_report(hdr, &rx);
2121                         } else
2122                                 prev = rx.sdata;
2123                 }
2124         } else list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2125                 if (!netif_running(sdata->dev))
2126                         continue;
2127
2128                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
2129                     sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2130                         continue;
2131
2132                 rx.flags |= IEEE80211_RX_RA_MATCH;
2133                 prepares = prepare_for_handlers(sdata, &rx, hdr);
2134
2135                 if (!prepares)
2136                         continue;
2137
2138                 if (status->flag & RX_FLAG_MMIC_ERROR) {
2139                         rx.sdata = sdata;
2140                         if (rx.flags & IEEE80211_RX_RA_MATCH)
2141                                 ieee80211_rx_michael_mic_report(hdr, &rx);
2142                         continue;
2143                 }
2144
2145                 /*
2146                  * frame is destined for this interface, but if it's not
2147                  * also for the previous one we handle that after the
2148                  * loop to avoid copying the SKB once too much
2149                  */
2150
2151                 if (!prev) {
2152                         prev = sdata;
2153                         continue;
2154                 }
2155
2156                 /*
2157                  * frame was destined for the previous interface
2158                  * so invoke RX handlers for it
2159                  */
2160
2161                 skb_new = skb_copy(skb, GFP_ATOMIC);
2162                 if (!skb_new) {
2163                         if (net_ratelimit())
2164                                 printk(KERN_DEBUG "%s: failed to copy "
2165                                        "multicast frame for %s\n",
2166                                        wiphy_name(local->hw.wiphy),
2167                                        prev->dev->name);
2168                         continue;
2169                 }
2170                 ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
2171                 prev = sdata;
2172         }
2173         if (prev)
2174                 ieee80211_invoke_rx_handlers(prev, &rx, skb);
2175         else
2176                 dev_kfree_skb(skb);
2177 }
2178
2179 #define SEQ_MODULO 0x1000
2180 #define SEQ_MASK   0xfff
2181
2182 static inline int seq_less(u16 sq1, u16 sq2)
2183 {
2184         return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
2185 }
2186
2187 static inline u16 seq_inc(u16 sq)
2188 {
2189         return (sq + 1) & SEQ_MASK;
2190 }
2191
2192 static inline u16 seq_sub(u16 sq1, u16 sq2)
2193 {
2194         return (sq1 - sq2) & SEQ_MASK;
2195 }
2196
2197
2198 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
2199                                             struct tid_ampdu_rx *tid_agg_rx,
2200                                             int index)
2201 {
2202         struct ieee80211_supported_band *sband;
2203         struct ieee80211_rate *rate;
2204         struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
2205         struct ieee80211_rx_status *status;
2206
2207         if (!skb)
2208                 goto no_frame;
2209
2210         status = IEEE80211_SKB_RXCB(skb);
2211
2212         /* release the reordered frames to stack */
2213         sband = hw->wiphy->bands[status->band];
2214         if (status->flag & RX_FLAG_HT)
2215                 rate = sband->bitrates; /* TODO: HT rates */
2216         else
2217                 rate = &sband->bitrates[status->rate_idx];
2218         __ieee80211_rx_handle_packet(hw, skb, rate);
2219         tid_agg_rx->stored_mpdu_num--;
2220         tid_agg_rx->reorder_buf[index] = NULL;
2221
2222 no_frame:
2223         tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
2224 }
2225
2226
2227 /*
2228  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
2229  * the skb was added to the buffer longer than this time ago, the earlier
2230  * frames that have not yet been received are assumed to be lost and the skb
2231  * can be released for processing. This may also release other skb's from the
2232  * reorder buffer if there are no additional gaps between the frames.
2233  */
2234 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
2235
2236 /*
2237  * As it function blongs to Rx path it must be called with
2238  * the proper rcu_read_lock protection for its flow.
2239  */
2240 static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
2241                                            struct tid_ampdu_rx *tid_agg_rx,
2242                                            struct sk_buff *skb,
2243                                            u16 mpdu_seq_num,
2244                                            int bar_req)
2245 {
2246         u16 head_seq_num, buf_size;
2247         int index;
2248
2249         buf_size = tid_agg_rx->buf_size;
2250         head_seq_num = tid_agg_rx->head_seq_num;
2251
2252         /* frame with out of date sequence number */
2253         if (seq_less(mpdu_seq_num, head_seq_num)) {
2254                 dev_kfree_skb(skb);
2255                 return 1;
2256         }
2257
2258         /* if frame sequence number exceeds our buffering window size or
2259          * block Ack Request arrived - release stored frames */
2260         if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
2261                 /* new head to the ordering buffer */
2262                 if (bar_req)
2263                         head_seq_num = mpdu_seq_num;
2264                 else
2265                         head_seq_num =
2266                                 seq_inc(seq_sub(mpdu_seq_num, buf_size));
2267                 /* release stored frames up to new head to stack */
2268                 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
2269                         index = seq_sub(tid_agg_rx->head_seq_num,
2270                                 tid_agg_rx->ssn)
2271                                 % tid_agg_rx->buf_size;
2272                         ieee80211_release_reorder_frame(hw, tid_agg_rx,
2273                                                         index);
2274                 }
2275                 if (bar_req)
2276                         return 1;
2277         }
2278
2279         /* now the new frame is always in the range of the reordering */
2280         /* buffer window */
2281         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
2282                                 % tid_agg_rx->buf_size;
2283         /* check if we already stored this frame */
2284         if (tid_agg_rx->reorder_buf[index]) {
2285                 dev_kfree_skb(skb);
2286                 return 1;
2287         }
2288
2289         /* if arrived mpdu is in the right order and nothing else stored */
2290         /* release it immediately */
2291         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
2292                         tid_agg_rx->stored_mpdu_num == 0) {
2293                 tid_agg_rx->head_seq_num =
2294                         seq_inc(tid_agg_rx->head_seq_num);
2295                 return 0;
2296         }
2297
2298         /* put the frame in the reordering buffer */
2299         tid_agg_rx->reorder_buf[index] = skb;
2300         tid_agg_rx->reorder_time[index] = jiffies;
2301         tid_agg_rx->stored_mpdu_num++;
2302         /* release the buffer until next missing frame */
2303         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
2304                                                 % tid_agg_rx->buf_size;
2305         if (!tid_agg_rx->reorder_buf[index] &&
2306             tid_agg_rx->stored_mpdu_num > 1) {
2307                 /*
2308                  * No buffers ready to be released, but check whether any
2309                  * frames in the reorder buffer have timed out.
2310                  */
2311                 int j;
2312                 int skipped = 1;
2313                 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
2314                      j = (j + 1) % tid_agg_rx->buf_size) {
2315                         if (tid_agg_rx->reorder_buf[j] == NULL) {
2316                                 skipped++;
2317                                 continue;
2318                         }
2319                         if (!time_after(jiffies, tid_agg_rx->reorder_time[j] +
2320                                         HZ / 10))
2321                                 break;
2322
2323 #ifdef CONFIG_MAC80211_HT_DEBUG
2324                         if (net_ratelimit())
2325                                 printk(KERN_DEBUG "%s: release an RX reorder "
2326                                        "frame due to timeout on earlier "
2327                                        "frames\n",
2328                                        wiphy_name(hw->wiphy));
2329 #endif
2330                         ieee80211_release_reorder_frame(hw, tid_agg_rx, j);
2331
2332                         /*
2333                          * Increment the head seq# also for the skipped slots.
2334                          */
2335                         tid_agg_rx->head_seq_num =
2336                                 (tid_agg_rx->head_seq_num + skipped) &
2337                                 SEQ_MASK;
2338                         skipped = 0;
2339                 }
2340         } else while (tid_agg_rx->reorder_buf[index]) {
2341                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
2342                 index = seq_sub(tid_agg_rx->head_seq_num,
2343                         tid_agg_rx->ssn) % tid_agg_rx->buf_size;
2344         }
2345         return 1;
2346 }
2347
2348 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
2349                                      struct sk_buff *skb)
2350 {
2351         struct ieee80211_hw *hw = &local->hw;
2352         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
2353         struct sta_info *sta;
2354         struct tid_ampdu_rx *tid_agg_rx;
2355         u16 sc;
2356         u16 mpdu_seq_num;
2357         u8 ret = 0;
2358         int tid;
2359
2360         sta = sta_info_get(local, hdr->addr2);
2361         if (!sta)
2362                 return ret;
2363
2364         /* filter the QoS data rx stream according to
2365          * STA/TID and check if this STA/TID is on aggregation */
2366         if (!ieee80211_is_data_qos(hdr->frame_control))
2367                 goto end_reorder;
2368
2369         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
2370
2371         if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
2372                 goto end_reorder;
2373
2374         tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
2375
2376         /* qos null data frames are excluded */
2377         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
2378                 goto end_reorder;
2379
2380         /* new un-ordered ampdu frame - process it */
2381
2382         /* reset session timer */
2383         if (tid_agg_rx->timeout)
2384                 mod_timer(&tid_agg_rx->session_timer,
2385                           TU_TO_EXP_TIME(tid_agg_rx->timeout));
2386
2387         /* if this mpdu is fragmented - terminate rx aggregation session */
2388         sc = le16_to_cpu(hdr->seq_ctrl);
2389         if (sc & IEEE80211_SCTL_FRAG) {
2390                 ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
2391                         tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
2392                 ret = 1;
2393                 goto end_reorder;
2394         }
2395
2396         /* according to mpdu sequence number deal with reordering buffer */
2397         mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
2398         ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb,
2399                                                 mpdu_seq_num, 0);
2400  end_reorder:
2401         return ret;
2402 }
2403
2404 /*
2405  * This is the receive path handler. It is called by a low level driver when an
2406  * 802.11 MPDU is received from the hardware.
2407  */
2408 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
2409 {
2410         struct ieee80211_local *local = hw_to_local(hw);
2411         struct ieee80211_rate *rate = NULL;
2412         struct ieee80211_supported_band *sband;
2413         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2414
2415         WARN_ON_ONCE(softirq_count() == 0);
2416
2417         if (WARN_ON(status->band < 0 ||
2418                     status->band >= IEEE80211_NUM_BANDS))
2419                 goto drop;
2420
2421         sband = local->hw.wiphy->bands[status->band];
2422         if (WARN_ON(!sband))
2423                 goto drop;
2424
2425         /*
2426          * If we're suspending, it is possible although not too likely
2427          * that we'd be receiving frames after having already partially
2428          * quiesced the stack. We can't process such frames then since
2429          * that might, for example, cause stations to be added or other
2430          * driver callbacks be invoked.
2431          */
2432         if (unlikely(local->quiescing || local->suspended))
2433                 goto drop;
2434
2435         /*
2436          * The same happens when we're not even started,
2437          * but that's worth a warning.
2438          */
2439         if (WARN_ON(!local->started))
2440                 goto drop;
2441
2442         if (status->flag & RX_FLAG_HT) {
2443                 /*
2444                  * rate_idx is MCS index, which can be [0-76] as documented on:
2445                  *
2446                  * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
2447                  *
2448                  * Anything else would be some sort of driver or hardware error.
2449                  * The driver should catch hardware errors.
2450                  */
2451                 if (WARN((status->rate_idx < 0 ||
2452                          status->rate_idx > 76),
2453                          "Rate marked as an HT rate but passed "
2454                          "status->rate_idx is not "
2455                          "an MCS index [0-76]: %d (0x%02x)\n",
2456                          status->rate_idx,
2457                          status->rate_idx))
2458                         goto drop;
2459                 /* HT rates are not in the table - use the highest legacy rate
2460                  * for now since other parts of mac80211 may not yet be fully
2461                  * MCS aware. */
2462                 rate = &sband->bitrates[sband->n_bitrates - 1];
2463         } else {
2464                 if (WARN_ON(status->rate_idx < 0 ||
2465                             status->rate_idx >= sband->n_bitrates))
2466                         goto drop;
2467                 rate = &sband->bitrates[status->rate_idx];
2468         }
2469
2470         /*
2471          * key references and virtual interfaces are protected using RCU
2472          * and this requires that we are in a read-side RCU section during
2473          * receive processing
2474          */
2475         rcu_read_lock();
2476
2477         /*
2478          * Frames with failed FCS/PLCP checksum are not returned,
2479          * all other frames are returned without radiotap header
2480          * if it was previously present.
2481          * Also, frames with less than 16 bytes are dropped.
2482          */
2483         skb = ieee80211_rx_monitor(local, skb, rate);
2484         if (!skb) {
2485                 rcu_read_unlock();
2486                 return;
2487         }
2488
2489         /*
2490          * In theory, the block ack reordering should happen after duplicate
2491          * removal (ieee80211_rx_h_check(), which is an RX handler). As such,
2492          * the call to ieee80211_rx_reorder_ampdu() should really be moved to
2493          * happen as a new RX handler between ieee80211_rx_h_check and
2494          * ieee80211_rx_h_decrypt. This cleanup may eventually happen, but for
2495          * the time being, the call can be here since RX reorder buf processing
2496          * will implicitly skip duplicates. We could, in theory at least,
2497          * process frames that ieee80211_rx_h_passive_scan would drop (e.g.,
2498          * frames from other than operational channel), but that should not
2499          * happen in normal networks.
2500          */
2501         if (!ieee80211_rx_reorder_ampdu(local, skb))
2502                 __ieee80211_rx_handle_packet(hw, skb, rate);
2503
2504         rcu_read_unlock();
2505
2506         return;
2507  drop:
2508         kfree_skb(skb);
2509 }
2510 EXPORT_SYMBOL(ieee80211_rx);
2511
2512 /* This is a version of the rx handler that can be called from hard irq
2513  * context. Post the skb on the queue and schedule the tasklet */
2514 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
2515 {
2516         struct ieee80211_local *local = hw_to_local(hw);
2517
2518         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2519
2520         skb->pkt_type = IEEE80211_RX_MSG;
2521         skb_queue_tail(&local->skb_queue, skb);
2522         tasklet_schedule(&local->tasklet);
2523 }
2524 EXPORT_SYMBOL(ieee80211_rx_irqsafe);