net/mac80211/rx.c

   1 /*
   2  * Copyright 2002-2005, Instant802 Networks, Inc.
   3  * Copyright 2005-2006, Devicescape Software, Inc.
   4  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   5  * Copyright 2007       Johannes Berg <johannes@sipsolutions.net>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/jiffies.h>
  13 #include <linux/kernel.h>
  14 #include <linux/skbuff.h>
  15 #include <linux/netdevice.h>
  16 #include <linux/etherdevice.h>
  17 #include <linux/rcupdate.h>
  18 #include <net/mac80211.h>
  19 #include <net/ieee80211_radiotap.h>
  20
  21 #include "ieee80211_i.h"
  22 #include "led.h"
  23 #include "mesh.h"
  24 #include "wep.h"
  25 #include "wpa.h"
  26 #include "tkip.h"
  27 #include "wme.h"
  28
  29 static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
  30                                            struct tid_ampdu_rx *tid_agg_rx,
  31                                            struct sk_buff *skb,
  32                                            struct ieee80211_rx_status *status,
  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                                            int rtap_len)
  44 {
  45         skb_pull(skb, rtap_len);
  46
  47         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
  48                 if (likely(skb->len > FCS_LEN))
  49                         skb_trim(skb, skb->len - FCS_LEN);
  50                 else {
  51                         /* driver bug */
  52                         WARN_ON(1);
  53                         dev_kfree_skb(skb);
  54                         skb = NULL;
  55                 }
  56         }
  57
  58         return skb;
  59 }
  60
  61 static inline int should_drop_frame(struct ieee80211_rx_status *status,
  62                                     struct sk_buff *skb,
  63                                     int present_fcs_len,
  64                                     int radiotap_len)
  65 {
  66         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  67
  68         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
  69                 return 1;
  70         if (unlikely(skb->len < 16 + present_fcs_len + radiotap_len))
  71                 return 1;
  72         if (ieee80211_is_ctl(hdr->frame_control) &&
  73             !ieee80211_is_pspoll(hdr->frame_control) &&
  74             !ieee80211_is_back_req(hdr->frame_control))
  75                 return 1;
  76         return 0;
  77 }
  78
  79 static int
  80 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
  81                           struct ieee80211_rx_status *status)
  82 {
  83         int len;
  84
  85         /* always present fields */
  86         len = sizeof(struct ieee80211_radiotap_header) + 9;
  87
  88         if (status->flag & RX_FLAG_TSFT)
  89                 len += 8;
  90         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
  91                 len += 1;
  92         if (local->hw.flags & IEEE80211_HW_NOISE_DBM)
  93                 len += 1;
  94
  95         if (len & 1) /* padding for RX_FLAGS if necessary */
  96                 len++;
  97
  98         /* make sure radiotap starts at a naturally aligned address */
  99         if (len % 8)
 100                 len = roundup(len, 8);
 101
 102         return len;
 103 }
 104
 105 /*
 106  * ieee80211_add_rx_radiotap_header - add radiotap header
 107  *
 108  * add a radiotap header containing all the fields which the hardware provided.
 109  */
 110 static void
 111 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
 112                                  struct sk_buff *skb,
 113                                  struct ieee80211_rx_status *status,
 114                                  struct ieee80211_rate *rate,
 115                                  int rtap_len)
 116 {
 117         struct ieee80211_radiotap_header *rthdr;
 118         unsigned char *pos;
 119
 120         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
 121         memset(rthdr, 0, rtap_len);
 122
 123         /* radiotap header, set always present flags */
 124         rthdr->it_present =
 125                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 126                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
 127                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
 128                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
 129         rthdr->it_len = cpu_to_le16(rtap_len);
 130
 131         pos = (unsigned char *)(rthdr+1);
 132
 133         /* the order of the following fields is important */
 134
 135         /* IEEE80211_RADIOTAP_TSFT */
 136         if (status->flag & RX_FLAG_TSFT) {
 137                 *(__le64 *)pos = cpu_to_le64(status->mactime);
 138                 rthdr->it_present |=
 139                         cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
 140                 pos += 8;
 141         }
 142
 143         /* IEEE80211_RADIOTAP_FLAGS */
 144         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 145                 *pos |= IEEE80211_RADIOTAP_F_FCS;
 146         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 147                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
 148         if (status->flag & RX_FLAG_SHORTPRE)
 149                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
 150         pos++;
 151
 152         /* IEEE80211_RADIOTAP_RATE */
 153         if (status->flag & RX_FLAG_HT) {
 154                 /*
 155                  * TODO: add following information into radiotap header once
 156                  * suitable fields are defined for it:
 157                  * - MCS index (status->rate_idx)
 158                  * - HT40 (status->flag & RX_FLAG_40MHZ)
 159                  * - short-GI (status->flag & RX_FLAG_SHORT_GI)
 160                  */
 161                 *pos = 0;
 162         } else {
 163                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
 164                 *pos = rate->bitrate / 5;
 165         }
 166         pos++;
 167
 168         /* IEEE80211_RADIOTAP_CHANNEL */
 169         *(__le16 *)pos = cpu_to_le16(status->freq);
 170         pos += 2;
 171         if (status->band == IEEE80211_BAND_5GHZ)
 172                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
 173                                              IEEE80211_CHAN_5GHZ);
 174         else if (rate->flags & IEEE80211_RATE_ERP_G)
 175                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM |
 176                                              IEEE80211_CHAN_2GHZ);
 177         else
 178                 *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_CCK |
 179                                              IEEE80211_CHAN_2GHZ);
 180         pos += 2;
 181
 182         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
 183         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
 184                 *pos = status->signal;
 185                 rthdr->it_present |=
 186                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
 187                 pos++;
 188         }
 189
 190         /* IEEE80211_RADIOTAP_DBM_ANTNOISE */
 191         if (local->hw.flags & IEEE80211_HW_NOISE_DBM) {
 192                 *pos = status->noise;
 193                 rthdr->it_present |=
 194                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE);
 195                 pos++;
 196         }
 197
 198         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
 199
 200         /* IEEE80211_RADIOTAP_ANTENNA */
 201         *pos = status->antenna;
 202         pos++;
 203
 204         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
 205
 206         /* IEEE80211_RADIOTAP_RX_FLAGS */
 207         /* ensure 2 byte alignment for the 2 byte field as required */
 208         if ((pos - (unsigned char *)rthdr) & 1)
 209                 pos++;
 210         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
 211                 *(__le16 *)pos |= cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADPLCP);
 212         pos += 2;
 213 }
 214
 215 /*
 216  * This function copies a received frame to all monitor interfaces and
 217  * returns a cleaned-up SKB that no longer includes the FCS nor the
 218  * radiotap header the driver might have added.
 219  */
 220 static struct sk_buff *
 221 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
 222                      struct ieee80211_rx_status *status,
 223                      struct ieee80211_rate *rate)
 224 {
 225         struct ieee80211_sub_if_data *sdata;
 226         int needed_headroom = 0;
 227         struct sk_buff *skb, *skb2;
 228         struct net_device *prev_dev = NULL;
 229         int present_fcs_len = 0;
 230         int rtap_len = 0;
 231
 232         /*
 233          * First, we may need to make a copy of the skb because
 234          *  (1) we need to modify it for radiotap (if not present), and
 235          *  (2) the other RX handlers will modify the skb we got.
 236          *
 237          * We don't need to, of course, if we aren't going to return
 238          * the SKB because it has a bad FCS/PLCP checksum.
 239          */
 240         if (status->flag & RX_FLAG_RADIOTAP)
 241                 rtap_len = ieee80211_get_radiotap_len(origskb->data);
 242         else
 243                 /* room for the radiotap header based on driver features */
 244                 needed_headroom = ieee80211_rx_radiotap_len(local, status);
 245
 246         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 247                 present_fcs_len = FCS_LEN;
 248
 249         if (!local->monitors) {
 250                 if (should_drop_frame(status, origskb, present_fcs_len,
 251                                       rtap_len)) {
 252                         dev_kfree_skb(origskb);
 253                         return NULL;
 254                 }
 255
 256                 return remove_monitor_info(local, origskb, rtap_len);
 257         }
 258
 259         if (should_drop_frame(status, origskb, present_fcs_len, rtap_len)) {
 260                 /* only need to expand headroom if necessary */
 261                 skb = origskb;
 262                 origskb = NULL;
 263
 264                 /*
 265                  * This shouldn't trigger often because most devices have an
 266                  * RX header they pull before we get here, and that should
 267                  * be big enough for our radiotap information. We should
 268                  * probably export the length to drivers so that we can have
 269                  * them allocate enough headroom to start with.
 270                  */
 271                 if (skb_headroom(skb) < needed_headroom &&
 272                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
 273                         dev_kfree_skb(skb);
 274                         return NULL;
 275                 }
 276         } else {
 277                 /*
 278                  * Need to make a copy and possibly remove radiotap header
 279                  * and FCS from the original.
 280                  */
 281                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
 282
 283                 origskb = remove_monitor_info(local, origskb, rtap_len);
 284
 285                 if (!skb)
 286                         return origskb;
 287         }
 288
 289         /* if necessary, prepend radiotap information */
 290         if (!(status->flag & RX_FLAG_RADIOTAP))
 291                 ieee80211_add_rx_radiotap_header(local, skb, status, rate,
 292                                                  needed_headroom);
 293
 294         skb_reset_mac_header(skb);
 295         skb->ip_summed = CHECKSUM_UNNECESSARY;
 296         skb->pkt_type = PACKET_OTHERHOST;
 297         skb->protocol = htons(ETH_P_802_2);
 298
 299         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 300                 if (!netif_running(sdata->dev))
 301                         continue;
 302
 303                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
 304                         continue;
 305
 306                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
 307                         continue;
 308
 309                 if (prev_dev) {
 310                         skb2 = skb_clone(skb, GFP_ATOMIC);
 311                         if (skb2) {
 312                                 skb2->dev = prev_dev;
 313                                 netif_rx(skb2);
 314                         }
 315                 }
 316
 317                 prev_dev = sdata->dev;
 318                 sdata->dev->stats.rx_packets++;
 319                 sdata->dev->stats.rx_bytes += skb->len;
 320         }
 321
 322         if (prev_dev) {
 323                 skb->dev = prev_dev;
 324                 netif_rx(skb);
 325         } else
 326                 dev_kfree_skb(skb);
 327
 328         return origskb;
 329 }
 330
 331
 332 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
 333 {
 334         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 335         int tid;
 336
 337         /* does the frame have a qos control field? */
 338         if (ieee80211_is_data_qos(hdr->frame_control)) {
 339                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 340                 /* frame has qos control */
 341                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
 342                 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
 343                         rx->flags |= IEEE80211_RX_AMSDU;
 344                 else
 345                         rx->flags &= ~IEEE80211_RX_AMSDU;
 346         } else {
 347                 /*
 348                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
 349                  *
 350                  *      Sequence numbers for management frames, QoS data
 351                  *      frames with a broadcast/multicast address in the
 352                  *      Address 1 field, and all non-QoS data frames sent
 353                  *      by QoS STAs are assigned using an additional single
 354                  *      modulo-4096 counter, [...]
 355                  *
 356                  * We also use that counter for non-QoS STAs.
 357                  */
 358                 tid = NUM_RX_DATA_QUEUES - 1;
 359         }
 360
 361         rx->queue = tid;
 362         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 363          * For now, set skb->priority to 0 for other cases. */
 364         rx->skb->priority = (tid > 7) ? 0 : tid;
 365 }
 366
 367 /**
 368  * DOC: Packet alignment
 369  *
 370  * Drivers always need to pass packets that are aligned to two-byte boundaries
 371  * to the stack.
 372  *
 373  * Additionally, should, if possible, align the payload data in a way that
 374  * guarantees that the contained IP header is aligned to a four-byte
 375  * boundary. In the case of regular frames, this simply means aligning the
 376  * payload to a four-byte boundary (because either the IP header is directly
 377  * contained, or IV/RFC1042 headers that have a length divisible by four are
 378  * in front of it).
 379  *
 380  * With A-MSDU frames, however, the payload data address must yield two modulo
 381  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
 382  * push the IP header further back to a multiple of four again. Thankfully, the
 383  * specs were sane enough this time around to require padding each A-MSDU
 384  * subframe to a length that is a multiple of four.
 385  *
 386  * Padding like Atheros hardware adds which is inbetween the 802.11 header and
 387  * the payload is not supported, the driver is required to move the 802.11
 388  * header to be directly in front of the payload in that case.
 389  */
 390 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
 391 {
 392         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 393         int hdrlen;
 394
 395 #ifndef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
 396         return;
 397 #endif
 398
 399         if (WARN_ONCE((unsigned long)rx->skb->data & 1,
 400                       "unaligned packet at 0x%p\n", rx->skb->data))
 401                 return;
 402
 403         if (!ieee80211_is_data_present(hdr->frame_control))
 404                 return;
 405
 406         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 407         if (rx->flags & IEEE80211_RX_AMSDU)
 408                 hdrlen += ETH_HLEN;
 409         WARN_ONCE(((unsigned long)(rx->skb->data + hdrlen)) & 3,
 410                   "unaligned IP payload at 0x%p\n", rx->skb->data + hdrlen);
 411 }
 412
 413
 414 /* rx handlers */
 415
 416 static ieee80211_rx_result debug_noinline
 417 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
 418 {
 419         struct ieee80211_local *local = rx->local;
 420         struct sk_buff *skb = rx->skb;
 421
 422         if (unlikely(local->hw_scanning))
 423                 return ieee80211_scan_rx(rx->sdata, skb, rx->status);
 424
 425         if (unlikely(local->sw_scanning)) {
 426                 /* drop all the other packets during a software scan anyway */
 427                 if (ieee80211_scan_rx(rx->sdata, skb, rx->status)
 428                     != RX_QUEUED)
 429                         dev_kfree_skb(skb);
 430                 return RX_QUEUED;
 431         }
 432
 433         if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
 434                 /* scanning finished during invoking of handlers */
 435                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
 436                 return RX_DROP_UNUSABLE;
 437         }
 438
 439         return RX_CONTINUE;
 440 }
 441
 442
 443 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
 444 {
 445         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 446
 447         if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
 448                 return 0;
 449
 450         return ieee80211_is_robust_mgmt_frame(hdr);
 451 }
 452
 453
 454 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
 455 {
 456         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 457
 458         if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
 459                 return 0;
 460
 461         return ieee80211_is_robust_mgmt_frame(hdr);
 462 }
 463
 464
 465 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
 466 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
 467 {
 468         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
 469         struct ieee80211_mmie *mmie;
 470
 471         if (skb->len < 24 + sizeof(*mmie) ||
 472             !is_multicast_ether_addr(hdr->da))
 473                 return -1;
 474
 475         if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
 476                 return -1; /* not a robust management frame */
 477
 478         mmie = (struct ieee80211_mmie *)
 479                 (skb->data + skb->len - sizeof(*mmie));
 480         if (mmie->element_id != WLAN_EID_MMIE ||
 481             mmie->length != sizeof(*mmie) - 2)
 482                 return -1;
 483
 484         return le16_to_cpu(mmie->key_id);
 485 }
 486
 487
 488 static ieee80211_rx_result
 489 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
 490 {
 491         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 492         unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
 493
 494         if (ieee80211_is_data(hdr->frame_control)) {
 495                 if (!ieee80211_has_a4(hdr->frame_control))
 496                         return RX_DROP_MONITOR;
 497                 if (memcmp(hdr->addr4, rx->dev->dev_addr, ETH_ALEN) == 0)
 498                         return RX_DROP_MONITOR;
 499         }
 500
 501         /* If there is not an established peer link and this is not a peer link
 502          * establisment frame, beacon or probe, drop the frame.
 503          */
 504
 505         if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
 506                 struct ieee80211_mgmt *mgmt;
 507
 508                 if (!ieee80211_is_mgmt(hdr->frame_control))
 509                         return RX_DROP_MONITOR;
 510
 511                 if (ieee80211_is_action(hdr->frame_control)) {
 512                         mgmt = (struct ieee80211_mgmt *)hdr;
 513                         if (mgmt->u.action.category != PLINK_CATEGORY)
 514                                 return RX_DROP_MONITOR;
 515                         return RX_CONTINUE;
 516                 }
 517
 518                 if (ieee80211_is_probe_req(hdr->frame_control) ||
 519                     ieee80211_is_probe_resp(hdr->frame_control) ||
 520                     ieee80211_is_beacon(hdr->frame_control))
 521                         return RX_CONTINUE;
 522
 523                 return RX_DROP_MONITOR;
 524
 525         }
 526
 527 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
 528
 529         if (ieee80211_is_data(hdr->frame_control) &&
 530             is_multicast_ether_addr(hdr->addr1) &&
 531             mesh_rmc_check(hdr->addr4, msh_h_get(hdr, hdrlen), rx->sdata))
 532                 return RX_DROP_MONITOR;
 533 #undef msh_h_get
 534
 535         return RX_CONTINUE;
 536 }
 537
 538
 539 static ieee80211_rx_result debug_noinline
 540 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
 541 {
 542         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 543
 544         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 545         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 546                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
 547                              rx->sta->last_seq_ctrl[rx->queue] ==
 548                              hdr->seq_ctrl)) {
 549                         if (rx->flags & IEEE80211_RX_RA_MATCH) {
 550                                 rx->local->dot11FrameDuplicateCount++;
 551                                 rx->sta->num_duplicates++;
 552                         }
 553                         return RX_DROP_MONITOR;
 554                 } else
 555                         rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
 556         }
 557
 558         if (unlikely(rx->skb->len < 16)) {
 559                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 560                 return RX_DROP_MONITOR;
 561         }
 562
 563         /* Drop disallowed frame classes based on STA auth/assoc state;
 564          * IEEE 802.11, Chap 5.5.
 565          *
 566          * mac80211 filters only based on association state, i.e. it drops
 567          * Class 3 frames from not associated stations. hostapd sends
 568          * deauth/disassoc frames when needed. In addition, hostapd is
 569          * responsible for filtering on both auth and assoc states.
 570          */
 571
 572         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
 573                 return ieee80211_rx_mesh_check(rx);
 574
 575         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
 576                       ieee80211_is_pspoll(hdr->frame_control)) &&
 577                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
 578                      (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
 579                 if ((!ieee80211_has_fromds(hdr->frame_control) &&
 580                      !ieee80211_has_tods(hdr->frame_control) &&
 581                      ieee80211_is_data(hdr->frame_control)) ||
 582                     !(rx->flags & IEEE80211_RX_RA_MATCH)) {
 583                         /* Drop IBSS frames and frames for other hosts
 584                          * silently. */
 585                         return RX_DROP_MONITOR;
 586                 }
 587
 588                 return RX_DROP_MONITOR;
 589         }
 590
 591         return RX_CONTINUE;
 592 }
 593
 594
 595 static ieee80211_rx_result debug_noinline
 596 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
 597 {
 598         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 599         int keyidx;
 600         int hdrlen;
 601         ieee80211_rx_result result = RX_DROP_UNUSABLE;
 602         struct ieee80211_key *stakey = NULL;
 603         int mmie_keyidx = -1;
 604
 605         /*
 606          * Key selection 101
 607          *
 608          * There are four types of keys:
 609          *  - GTK (group keys)
 610          *  - IGTK (group keys for management frames)
 611          *  - PTK (pairwise keys)
 612          *  - STK (station-to-station pairwise keys)
 613          *
 614          * When selecting a key, we have to distinguish between multicast
 615          * (including broadcast) and unicast frames, the latter can only
 616          * use PTKs and STKs while the former always use GTKs and IGTKs.
 617          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
 618          * unicast frames can also use key indices like GTKs. Hence, if we
 619          * don't have a PTK/STK we check the key index for a WEP key.
 620          *
 621          * Note that in a regular BSS, multicast frames are sent by the
 622          * AP only, associated stations unicast the frame to the AP first
 623          * which then multicasts it on their behalf.
 624          *
 625          * There is also a slight problem in IBSS mode: GTKs are negotiated
 626          * with each station, that is something we don't currently handle.
 627          * The spec seems to expect that one negotiates the same key with
 628          * every station but there's no such requirement; VLANs could be
 629          * possible.
 630          */
 631
 632         if (!ieee80211_has_protected(hdr->frame_control)) {
 633                 if (!ieee80211_is_mgmt(hdr->frame_control) ||
 634                     rx->sta == NULL || !test_sta_flags(rx->sta, WLAN_STA_MFP))
 635                         return RX_CONTINUE;
 636                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
 637                 if (mmie_keyidx < 0)
 638                         return RX_CONTINUE;
 639         }
 640
 641         /*
 642          * No point in finding a key and decrypting if the frame is neither
 643          * addressed to us nor a multicast frame.
 644          */
 645         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
 646                 return RX_CONTINUE;
 647
 648         if (rx->sta)
 649                 stakey = rcu_dereference(rx->sta->key);
 650
 651         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
 652                 rx->key = stakey;
 653         } else if (mmie_keyidx >= 0) {
 654                 /* Broadcast/multicast robust management frame / BIP */
 655                 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
 656                     (rx->status->flag & RX_FLAG_IV_STRIPPED))
 657                         return RX_CONTINUE;
 658
 659                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
 660                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
 661                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
 662                 rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
 663         } else {
 664                 /*
 665                  * The device doesn't give us the IV so we won't be
 666                  * able to look up the key. That's ok though, we
 667                  * don't need to decrypt the frame, we just won't
 668                  * be able to keep statistics accurate.
 669                  * Except for key threshold notifications, should
 670                  * we somehow allow the driver to tell us which key
 671                  * the hardware used if this flag is set?
 672                  */
 673                 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
 674                     (rx->status->flag & RX_FLAG_IV_STRIPPED))
 675                         return RX_CONTINUE;
 676
 677                 hdrlen = ieee80211_hdrlen(hdr->frame_control);
 678
 679                 if (rx->skb->len < 8 + hdrlen)
 680                         return RX_DROP_UNUSABLE; /* TODO: count this? */
 681
 682                 /*
 683                  * no need to call ieee80211_wep_get_keyidx,
 684                  * it verifies a bunch of things we've done already
 685                  */
 686                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
 687
 688                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
 689
 690                 /*
 691                  * RSNA-protected unicast frames should always be sent with
 692                  * pairwise or station-to-station keys, but for WEP we allow
 693                  * using a key index as well.
 694                  */
 695                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
 696                     !is_multicast_ether_addr(hdr->addr1))
 697                         rx->key = NULL;
 698         }
 699
 700         if (rx->key) {
 701                 rx->key->tx_rx_count++;
 702                 /* TODO: add threshold stuff again */
 703         } else {
 704                 return RX_DROP_MONITOR;
 705         }
 706
 707         /* Check for weak IVs if possible */
 708         if (rx->sta && rx->key->conf.alg == ALG_WEP &&
 709             ieee80211_is_data(hdr->frame_control) &&
 710             (!(rx->status->flag & RX_FLAG_IV_STRIPPED) ||
 711              !(rx->status->flag & RX_FLAG_DECRYPTED)) &&
 712             ieee80211_wep_is_weak_iv(rx->skb, rx->key))
 713                 rx->sta->wep_weak_iv_count++;
 714
 715         switch (rx->key->conf.alg) {
 716         case ALG_WEP:
 717                 result = ieee80211_crypto_wep_decrypt(rx);
 718                 break;
 719         case ALG_TKIP:
 720                 result = ieee80211_crypto_tkip_decrypt(rx);
 721                 break;
 722         case ALG_CCMP:
 723                 result = ieee80211_crypto_ccmp_decrypt(rx);
 724                 break;
 725         case ALG_AES_CMAC:
 726                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
 727                 break;
 728         }
 729
 730         /* either the frame has been decrypted or will be dropped */
 731         rx->status->flag |= RX_FLAG_DECRYPTED;
 732
 733         return result;
 734 }
 735
 736 static ieee80211_rx_result debug_noinline
 737 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
 738 {
 739         struct ieee80211_local *local;
 740         struct ieee80211_hdr *hdr;
 741         struct sk_buff *skb;
 742
 743         local = rx->local;
 744         skb = rx->skb;
 745         hdr = (struct ieee80211_hdr *) skb->data;
 746
 747         if (!local->pspolling)
 748                 return RX_CONTINUE;
 749
 750         if (!ieee80211_has_fromds(hdr->frame_control))
 751                 /* this is not from AP */
 752                 return RX_CONTINUE;
 753
 754         if (!ieee80211_is_data(hdr->frame_control))
 755                 return RX_CONTINUE;
 756
 757         if (!ieee80211_has_moredata(hdr->frame_control)) {
 758                 /* AP has no more frames buffered for us */
 759                 local->pspolling = false;
 760                 return RX_CONTINUE;
 761         }
 762
 763         /* more data bit is set, let's request a new frame from the AP */
 764         ieee80211_send_pspoll(local, rx->sdata);
 765
 766         return RX_CONTINUE;
 767 }
 768
 769 static void ap_sta_ps_start(struct sta_info *sta)
 770 {
 771         struct ieee80211_sub_if_data *sdata = sta->sdata;
 772         struct ieee80211_local *local = sdata->local;
 773
 774         atomic_inc(&sdata->bss->num_sta_ps);
 775         set_and_clear_sta_flags(sta, WLAN_STA_PS, WLAN_STA_PSPOLL);
 776         if (local->ops->sta_notify)
 777                 local->ops->sta_notify(local_to_hw(local), &sdata->vif,
 778                                         STA_NOTIFY_SLEEP, &sta->sta);
 779 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 780         printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
 781                sdata->dev->name, sta->sta.addr, sta->sta.aid);
 782 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 783 }
 784
 785 static int ap_sta_ps_end(struct sta_info *sta)
 786 {
 787         struct ieee80211_sub_if_data *sdata = sta->sdata;
 788         struct ieee80211_local *local = sdata->local;
 789         struct sk_buff *skb;
 790         int sent = 0;
 791
 792         atomic_dec(&sdata->bss->num_sta_ps);
 793
 794         clear_sta_flags(sta, WLAN_STA_PS | WLAN_STA_PSPOLL);
 795         if (local->ops->sta_notify)
 796                 local->ops->sta_notify(local_to_hw(local), &sdata->vif,
 797                                         STA_NOTIFY_AWAKE, &sta->sta);
 798
 799         if (!skb_queue_empty(&sta->ps_tx_buf))
 800                 sta_info_clear_tim_bit(sta);
 801
 802 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 803         printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
 804                sdata->dev->name, sta->sta.addr, sta->sta.aid);
 805 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 806
 807         /* Send all buffered frames to the station */
 808         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
 809                 sent++;
 810                 skb->requeue = 1;
 811                 dev_queue_xmit(skb);
 812         }
 813         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
 814                 local->total_ps_buffered--;
 815                 sent++;
 816 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
 817                 printk(KERN_DEBUG "%s: STA %pM aid %d send PS frame "
 818                        "since STA not sleeping anymore\n", sdata->dev->name,
 819                        sta->sta.addr, sta->sta.aid);
 820 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
 821                 skb->requeue = 1;
 822                 dev_queue_xmit(skb);
 823         }
 824
 825         return sent;
 826 }
 827
 828 static ieee80211_rx_result debug_noinline
 829 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
 830 {
 831         struct sta_info *sta = rx->sta;
 832         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 833
 834         if (!sta)
 835                 return RX_CONTINUE;
 836
 837         /* Update last_rx only for IBSS packets which are for the current
 838          * BSSID to avoid keeping the current IBSS network alive in cases where
 839          * other STAs are using different BSSID. */
 840         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
 841                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
 842                                                 NL80211_IFTYPE_ADHOC);
 843                 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0)
 844                         sta->last_rx = jiffies;
 845         } else
 846         if (!is_multicast_ether_addr(hdr->addr1) ||
 847             rx->sdata->vif.type == NL80211_IFTYPE_STATION) {
 848                 /* Update last_rx only for unicast frames in order to prevent
 849                  * the Probe Request frames (the only broadcast frames from a
 850                  * STA in infrastructure mode) from keeping a connection alive.
 851                  * Mesh beacons will update last_rx when if they are found to
 852                  * match the current local configuration when processed.
 853                  */
 854                 if (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
 855                     ieee80211_is_beacon(hdr->frame_control)) {
 856                         rx->sdata->u.mgd.last_beacon = jiffies;
 857                 } else
 858                         sta->last_rx = jiffies;
 859         }
 860
 861         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
 862                 return RX_CONTINUE;
 863
 864         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
 865                 ieee80211_sta_rx_notify(rx->sdata, hdr);
 866
 867         sta->rx_fragments++;
 868         sta->rx_bytes += rx->skb->len;
 869         sta->last_signal = rx->status->signal;
 870         sta->last_qual = rx->status->qual;
 871         sta->last_noise = rx->status->noise;
 872
 873         /*
 874          * Change STA power saving mode only at the end of a frame
 875          * exchange sequence.
 876          */
 877         if (!ieee80211_has_morefrags(hdr->frame_control) &&
 878             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
 879              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
 880                 if (test_sta_flags(sta, WLAN_STA_PS)) {
 881                         /*
 882                          * Ignore doze->wake transitions that are
 883                          * indicated by non-data frames, the standard
 884                          * is unclear here, but for example going to
 885                          * PS mode and then scanning would cause a
 886                          * doze->wake transition for the probe request,
 887                          * and that is clearly undesirable.
 888                          */
 889                         if (ieee80211_is_data(hdr->frame_control) &&
 890                             !ieee80211_has_pm(hdr->frame_control))
 891                                 rx->sent_ps_buffered += ap_sta_ps_end(sta);
 892                 } else {
 893                         if (ieee80211_has_pm(hdr->frame_control))
 894                                 ap_sta_ps_start(sta);
 895                 }
 896         }
 897
 898         /* Drop data::nullfunc frames silently, since they are used only to
 899          * control station power saving mode. */
 900         if (ieee80211_is_nullfunc(hdr->frame_control)) {
 901                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
 902                 /* Update counter and free packet here to avoid counting this
 903                  * as a dropped packed. */
 904                 sta->rx_packets++;
 905                 dev_kfree_skb(rx->skb);
 906                 return RX_QUEUED;
 907         }
 908
 909         return RX_CONTINUE;
 910 } /* ieee80211_rx_h_sta_process */
 911
 912 static inline struct ieee80211_fragment_entry *
 913 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
 914                          unsigned int frag, unsigned int seq, int rx_queue,
 915                          struct sk_buff **skb)
 916 {
 917         struct ieee80211_fragment_entry *entry;
 918         int idx;
 919
 920         idx = sdata->fragment_next;
 921         entry = &sdata->fragments[sdata->fragment_next++];
 922         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
 923                 sdata->fragment_next = 0;
 924
 925         if (!skb_queue_empty(&entry->skb_list)) {
 926 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 927                 struct ieee80211_hdr *hdr =
 928                         (struct ieee80211_hdr *) entry->skb_list.next->data;
 929                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
 930                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
 931                        "addr1=%pM addr2=%pM\n",
 932                        sdata->dev->name, idx,
 933                        jiffies - entry->first_frag_time, entry->seq,
 934                        entry->last_frag, hdr->addr1, hdr->addr2);
 935 #endif
 936                 __skb_queue_purge(&entry->skb_list);
 937         }
 938
 939         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
 940         *skb = NULL;
 941         entry->first_frag_time = jiffies;
 942         entry->seq = seq;
 943         entry->rx_queue = rx_queue;
 944         entry->last_frag = frag;
 945         entry->ccmp = 0;
 946         entry->extra_len = 0;
 947
 948         return entry;
 949 }
 950
 951 static inline struct ieee80211_fragment_entry *
 952 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
 953                           unsigned int frag, unsigned int seq,
 954                           int rx_queue, struct ieee80211_hdr *hdr)
 955 {
 956         struct ieee80211_fragment_entry *entry;
 957         int i, idx;
 958
 959         idx = sdata->fragment_next;
 960         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
 961                 struct ieee80211_hdr *f_hdr;
 962
 963                 idx--;
 964                 if (idx < 0)
 965                         idx = IEEE80211_FRAGMENT_MAX - 1;
 966
 967                 entry = &sdata->fragments[idx];
 968                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
 969                     entry->rx_queue != rx_queue ||
 970                     entry->last_frag + 1 != frag)
 971                         continue;
 972
 973                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
 974
 975                 /*
 976                  * Check ftype and addresses are equal, else check next fragment
 977                  */
 978                 if (((hdr->frame_control ^ f_hdr->frame_control) &
 979                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
 980                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
 981                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
 982                         continue;
 983
 984                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
 985                         __skb_queue_purge(&entry->skb_list);
 986                         continue;
 987                 }
 988                 return entry;
 989         }
 990
 991         return NULL;
 992 }
 993
 994 static ieee80211_rx_result debug_noinline
 995 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
 996 {
 997         struct ieee80211_hdr *hdr;
 998         u16 sc;
 999         __le16 fc;
1000         unsigned int frag, seq;
1001         struct ieee80211_fragment_entry *entry;
1002         struct sk_buff *skb;
1003
1004         hdr = (struct ieee80211_hdr *)rx->skb->data;
1005         fc = hdr->frame_control;
1006         sc = le16_to_cpu(hdr->seq_ctrl);
1007         frag = sc & IEEE80211_SCTL_FRAG;
1008
1009         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1010                    (rx->skb)->len < 24 ||
1011                    is_multicast_ether_addr(hdr->addr1))) {
1012                 /* not fragmented */
1013                 goto out;
1014         }
1015         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1016
1017         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1018
1019         if (frag == 0) {
1020                 /* This is the first fragment of a new frame. */
1021                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1022                                                  rx->queue, &(rx->skb));
1023                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
1024                     ieee80211_has_protected(fc)) {
1025                         /* Store CCMP PN so that we can verify that the next
1026                          * fragment has a sequential PN value. */
1027                         entry->ccmp = 1;
1028                         memcpy(entry->last_pn,
1029                                rx->key->u.ccmp.rx_pn[rx->queue],
1030                                CCMP_PN_LEN);
1031                 }
1032                 return RX_QUEUED;
1033         }
1034
1035         /* This is a fragment for a frame that should already be pending in
1036          * fragment cache. Add this fragment to the end of the pending entry.
1037          */
1038         entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
1039         if (!entry) {
1040                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1041                 return RX_DROP_MONITOR;
1042         }
1043
1044         /* Verify that MPDUs within one MSDU have sequential PN values.
1045          * (IEEE 802.11i, 8.3.3.4.5) */
1046         if (entry->ccmp) {
1047                 int i;
1048                 u8 pn[CCMP_PN_LEN], *rpn;
1049                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
1050                         return RX_DROP_UNUSABLE;
1051                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1052                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1053                         pn[i]++;
1054                         if (pn[i])
1055                                 break;
1056                 }
1057                 rpn = rx->key->u.ccmp.rx_pn[rx->queue];
1058                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1059                         return RX_DROP_UNUSABLE;
1060                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1061         }
1062
1063         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1064         __skb_queue_tail(&entry->skb_list, rx->skb);
1065         entry->last_frag = frag;
1066         entry->extra_len += rx->skb->len;
1067         if (ieee80211_has_morefrags(fc)) {
1068                 rx->skb = NULL;
1069                 return RX_QUEUED;
1070         }
1071
1072         rx->skb = __skb_dequeue(&entry->skb_list);
1073         if (skb_tailroom(rx->skb) < entry->extra_len) {
1074                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1075                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1076                                               GFP_ATOMIC))) {
1077                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1078                         __skb_queue_purge(&entry->skb_list);
1079                         return RX_DROP_UNUSABLE;
1080                 }
1081         }
1082         while ((skb = __skb_dequeue(&entry->skb_list))) {
1083                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1084                 dev_kfree_skb(skb);
1085         }
1086
1087         /* Complete frame has been reassembled - process it now */
1088         rx->flags |= IEEE80211_RX_FRAGMENTED;
1089
1090  out:
1091         if (rx->sta)
1092                 rx->sta->rx_packets++;
1093         if (is_multicast_ether_addr(hdr->addr1))
1094                 rx->local->dot11MulticastReceivedFrameCount++;
1095         else
1096                 ieee80211_led_rx(rx->local);
1097         return RX_CONTINUE;
1098 }
1099
1100 static ieee80211_rx_result debug_noinline
1101 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
1102 {
1103         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1104         struct sk_buff *skb;
1105         int no_pending_pkts;
1106         __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
1107
1108         if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
1109                    !(rx->flags & IEEE80211_RX_RA_MATCH)))
1110                 return RX_CONTINUE;
1111
1112         if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1113             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1114                 return RX_DROP_UNUSABLE;
1115
1116         skb = skb_dequeue(&rx->sta->tx_filtered);
1117         if (!skb) {
1118                 skb = skb_dequeue(&rx->sta->ps_tx_buf);
1119                 if (skb)
1120                         rx->local->total_ps_buffered--;
1121         }
1122         no_pending_pkts = skb_queue_empty(&rx->sta->tx_filtered) &&
1123                 skb_queue_empty(&rx->sta->ps_tx_buf);
1124
1125         if (skb) {
1126                 struct ieee80211_hdr *hdr =
1127                         (struct ieee80211_hdr *) skb->data;
1128
1129                 /*
1130                  * Tell TX path to send one frame even though the STA may
1131                  * still remain is PS mode after this frame exchange.
1132                  */
1133                 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1134
1135 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1136                 printk(KERN_DEBUG "STA %pM aid %d: PS Poll (entries after %d)\n",
1137                        rx->sta->sta.addr, rx->sta->sta.aid,
1138                        skb_queue_len(&rx->sta->ps_tx_buf));
1139 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1140
1141                 /* Use MoreData flag to indicate whether there are more
1142                  * buffered frames for this STA */
1143                 if (no_pending_pkts)
1144                         hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
1145                 else
1146                         hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1147
1148                 dev_queue_xmit(skb);
1149
1150                 if (no_pending_pkts)
1151                         sta_info_clear_tim_bit(rx->sta);
1152 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1153         } else if (!rx->sent_ps_buffered) {
1154                 /*
1155                  * FIXME: This can be the result of a race condition between
1156                  *        us expiring a frame and the station polling for it.
1157                  *        Should we send it a null-func frame indicating we
1158                  *        have nothing buffered for it?
1159                  */
1160                 printk(KERN_DEBUG "%s: STA %pM sent PS Poll even "
1161                        "though there are no buffered frames for it\n",
1162                        rx->dev->name, rx->sta->sta.addr);
1163 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1164         }
1165
1166         /* Free PS Poll skb here instead of returning RX_DROP that would
1167          * count as an dropped frame. */
1168         dev_kfree_skb(rx->skb);
1169
1170         return RX_QUEUED;
1171 }
1172
1173 static ieee80211_rx_result debug_noinline
1174 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1175 {
1176         u8 *data = rx->skb->data;
1177         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1178
1179         if (!ieee80211_is_data_qos(hdr->frame_control))
1180                 return RX_CONTINUE;
1181
1182         /* remove the qos control field, update frame type and meta-data */
1183         memmove(data + IEEE80211_QOS_CTL_LEN, data,
1184                 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1185         hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1186         /* change frame type to non QOS */
1187         hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1188
1189         return RX_CONTINUE;
1190 }
1191
1192 static int
1193 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1194 {
1195         if (unlikely(!rx->sta ||
1196             !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1197                 return -EACCES;
1198
1199         return 0;
1200 }
1201
1202 static int
1203 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1204 {
1205         /*
1206          * Pass through unencrypted frames if the hardware has
1207          * decrypted them already.
1208          */
1209         if (rx->status->flag & RX_FLAG_DECRYPTED)
1210                 return 0;
1211
1212         /* Drop unencrypted frames if key is set. */
1213         if (unlikely(!ieee80211_has_protected(fc) &&
1214                      !ieee80211_is_nullfunc(fc) &&
1215                      (!ieee80211_is_mgmt(fc) ||
1216                       (ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1217                        rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP))) &&
1218                      (rx->key || rx->sdata->drop_unencrypted)))
1219                 return -EACCES;
1220         /* BIP does not use Protected field, so need to check MMIE */
1221         if (unlikely(rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP) &&
1222                      ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1223                      ieee80211_get_mmie_keyidx(rx->skb) < 0 &&
1224                      (rx->key || rx->sdata->drop_unencrypted)))
1225                 return -EACCES;
1226
1227         return 0;
1228 }
1229
1230 static int
1231 ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1232 {
1233         struct net_device *dev = rx->dev;
1234         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
1235         u16 hdrlen, ethertype;
1236         u8 *payload;
1237         u8 dst[ETH_ALEN];
1238         u8 src[ETH_ALEN] __aligned(2);
1239         struct sk_buff *skb = rx->skb;
1240         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1241
1242         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1243                 return -1;
1244
1245         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1246
1247         /* convert IEEE 802.11 header + possible LLC headers into Ethernet
1248          * header
1249          * IEEE 802.11 address fields:
1250          * ToDS FromDS Addr1 Addr2 Addr3 Addr4
1251          *   0     0   DA    SA    BSSID n/a
1252          *   0     1   DA    BSSID SA    n/a
1253          *   1     0   BSSID SA    DA    n/a
1254          *   1     1   RA    TA    DA    SA
1255          */
1256         memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
1257         memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);
1258
1259         switch (hdr->frame_control &
1260                 cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
1261         case cpu_to_le16(IEEE80211_FCTL_TODS):
1262                 if (unlikely(sdata->vif.type != NL80211_IFTYPE_AP &&
1263                              sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1264                         return -1;
1265                 break;
1266         case cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
1267                 if (unlikely(sdata->vif.type != NL80211_IFTYPE_WDS &&
1268                              sdata->vif.type != NL80211_IFTYPE_MESH_POINT))
1269                         return -1;
1270                 if (ieee80211_vif_is_mesh(&sdata->vif)) {
1271                         struct ieee80211s_hdr *meshdr = (struct ieee80211s_hdr *)
1272                                 (skb->data + hdrlen);
1273                         hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
1274                         if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
1275                                 memcpy(dst, meshdr->eaddr1, ETH_ALEN);
1276                                 memcpy(src, meshdr->eaddr2, ETH_ALEN);
1277                         }
1278                 }
1279                 break;
1280         case cpu_to_le16(IEEE80211_FCTL_FROMDS):
1281                 if (sdata->vif.type != NL80211_IFTYPE_STATION ||
1282                     (is_multicast_ether_addr(dst) &&
1283                      !compare_ether_addr(src, dev->dev_addr)))
1284                         return -1;
1285                 break;
1286         case cpu_to_le16(0):
1287                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1288                         return -1;
1289                 break;
1290         }
1291
1292         if (unlikely(skb->len - hdrlen < 8))
1293                 return -1;
1294
1295         payload = skb->data + hdrlen;
1296         ethertype = (payload[6] << 8) | payload[7];
1297
1298         if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1299                     ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1300                    compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
1301                 /* remove RFC1042 or Bridge-Tunnel encapsulation and
1302                  * replace EtherType */
1303                 skb_pull(skb, hdrlen + 6);
1304                 memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
1305                 memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
1306         } else {
1307                 struct ethhdr *ehdr;
1308                 __be16 len;
1309
1310                 skb_pull(skb, hdrlen);
1311                 len = htons(skb->len);
1312                 ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
1313                 memcpy(ehdr->h_dest, dst, ETH_ALEN);
1314                 memcpy(ehdr->h_source, src, ETH_ALEN);
1315                 ehdr->h_proto = len;
1316         }
1317         return 0;
1318 }
1319
1320 /*
1321  * requires that rx->skb is a frame with ethernet header
1322  */
1323 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1324 {
1325         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1326                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1327         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1328
1329         /*
1330          * Allow EAPOL frames to us/the PAE group address regardless
1331          * of whether the frame was encrypted or not.
1332          */
1333         if (ehdr->h_proto == htons(ETH_P_PAE) &&
1334             (compare_ether_addr(ehdr->h_dest, rx->dev->dev_addr) == 0 ||
1335              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1336                 return true;
1337
1338         if (ieee80211_802_1x_port_control(rx) ||
1339             ieee80211_drop_unencrypted(rx, fc))
1340                 return false;
1341
1342         return true;
1343 }
1344
1345 /*
1346  * requires that rx->skb is a frame with ethernet header
1347  */
1348 static void
1349 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1350 {
1351         struct net_device *dev = rx->dev;
1352         struct ieee80211_local *local = rx->local;
1353         struct sk_buff *skb, *xmit_skb;
1354         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1355         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1356         struct sta_info *dsta;
1357
1358         skb = rx->skb;
1359         xmit_skb = NULL;
1360
1361         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1362              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1363             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1364             (rx->flags & IEEE80211_RX_RA_MATCH)) {
1365                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1366                         /*
1367                          * send multicast frames both to higher layers in
1368                          * local net stack and back to the wireless medium
1369                          */
1370                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1371                         if (!xmit_skb && net_ratelimit())
1372                                 printk(KERN_DEBUG "%s: failed to clone "
1373                                        "multicast frame\n", dev->name);
1374                 } else {
1375                         dsta = sta_info_get(local, skb->data);
1376                         if (dsta && dsta->sdata->dev == dev) {
1377                                 /*
1378                                  * The destination station is associated to
1379                                  * this AP (in this VLAN), so send the frame
1380                                  * directly to it and do not pass it to local
1381                                  * net stack.
1382                                  */
1383                                 xmit_skb = skb;
1384                                 skb = NULL;
1385                         }
1386                 }
1387         }
1388
1389         if (skb) {
1390                 int align __maybe_unused;
1391
1392 #if defined(CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT) || !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
1393                 /*
1394                  * 'align' will only take the values 0 or 2 here
1395                  * since all frames are required to be aligned
1396                  * to 2-byte boundaries when being passed to
1397                  * mac80211. That also explains the __skb_push()
1398                  * below.
1399                  */
1400                 align = (unsigned long)skb->data & 3;
1401                 if (align) {
1402                         if (WARN_ON(skb_headroom(skb) < 3)) {
1403                                 dev_kfree_skb(skb);
1404                                 skb = NULL;
1405                         } else {
1406                                 u8 *data = skb->data;
1407                                 size_t len = skb->len;
1408                                 u8 *new = __skb_push(skb, align);
1409                                 memmove(new, data, len);
1410                                 __skb_trim(skb, len);
1411                         }
1412                 }
1413 #endif
1414
1415                 if (skb) {
1416                         /* deliver to local stack */
1417                         skb->protocol = eth_type_trans(skb, dev);
1418                         memset(skb->cb, 0, sizeof(skb->cb));
1419                         netif_rx(skb);
1420                 }
1421         }
1422
1423         if (xmit_skb) {
1424                 /* send to wireless media */
1425                 xmit_skb->protocol = htons(ETH_P_802_3);
1426                 skb_reset_network_header(xmit_skb);
1427                 skb_reset_mac_header(xmit_skb);
1428                 dev_queue_xmit(xmit_skb);
1429         }
1430 }
1431
1432 static ieee80211_rx_result debug_noinline
1433 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1434 {
1435         struct net_device *dev = rx->dev;
1436         struct ieee80211_local *local = rx->local;
1437         u16 ethertype;
1438         u8 *payload;
1439         struct sk_buff *skb = rx->skb, *frame = NULL;
1440         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1441         __le16 fc = hdr->frame_control;
1442         const struct ethhdr *eth;
1443         int remaining, err;
1444         u8 dst[ETH_ALEN];
1445         u8 src[ETH_ALEN];
1446
1447         if (unlikely(!ieee80211_is_data(fc)))
1448                 return RX_CONTINUE;
1449
1450         if (unlikely(!ieee80211_is_data_present(fc)))
1451                 return RX_DROP_MONITOR;
1452
1453         if (!(rx->flags & IEEE80211_RX_AMSDU))
1454                 return RX_CONTINUE;
1455
1456         err = ieee80211_data_to_8023(rx);
1457         if (unlikely(err))
1458                 return RX_DROP_UNUSABLE;
1459
1460         skb->dev = dev;
1461
1462         dev->stats.rx_packets++;
1463         dev->stats.rx_bytes += skb->len;
1464
1465         /* skip the wrapping header */
1466         eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
1467         if (!eth)
1468                 return RX_DROP_UNUSABLE;
1469
1470         while (skb != frame) {
1471                 u8 padding;
1472                 __be16 len = eth->h_proto;
1473                 unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
1474
1475                 remaining = skb->len;
1476                 memcpy(dst, eth->h_dest, ETH_ALEN);
1477                 memcpy(src, eth->h_source, ETH_ALEN);
1478
1479                 padding = ((4 - subframe_len) & 0x3);
1480                 /* the last MSDU has no padding */
1481                 if (subframe_len > remaining)
1482                         return RX_DROP_UNUSABLE;
1483
1484                 skb_pull(skb, sizeof(struct ethhdr));
1485                 /* if last subframe reuse skb */
1486                 if (remaining <= subframe_len + padding)
1487                         frame = skb;
1488                 else {
1489                         /*
1490                          * Allocate and reserve two bytes more for payload
1491                          * alignment since sizeof(struct ethhdr) is 14.
1492                          */
1493                         frame = dev_alloc_skb(
1494                                 ALIGN(local->hw.extra_tx_headroom, 4) +
1495                                 subframe_len + 2);
1496
1497                         if (frame == NULL)
1498                                 return RX_DROP_UNUSABLE;
1499
1500                         skb_reserve(frame,
1501                                     ALIGN(local->hw.extra_tx_headroom, 4) +
1502                                     sizeof(struct ethhdr) + 2);
1503                         memcpy(skb_put(frame, ntohs(len)), skb->data,
1504                                 ntohs(len));
1505
1506                         eth = (struct ethhdr *) skb_pull(skb, ntohs(len) +
1507                                                         padding);
1508                         if (!eth) {
1509                                 dev_kfree_skb(frame);
1510                                 return RX_DROP_UNUSABLE;
1511                         }
1512                 }
1513
1514                 skb_reset_network_header(frame);
1515                 frame->dev = dev;
1516                 frame->priority = skb->priority;
1517                 rx->skb = frame;
1518
1519                 payload = frame->data;
1520                 ethertype = (payload[6] << 8) | payload[7];
1521
1522                 if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
1523                             ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
1524                            compare_ether_addr(payload,
1525                                               bridge_tunnel_header) == 0)) {
1526                         /* remove RFC1042 or Bridge-Tunnel
1527                          * encapsulation and replace EtherType */
1528                         skb_pull(frame, 6);
1529                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1530                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1531                 } else {
1532                         memcpy(skb_push(frame, sizeof(__be16)),
1533                                &len, sizeof(__be16));
1534                         memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
1535                         memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
1536                 }
1537
1538                 if (!ieee80211_frame_allowed(rx, fc)) {
1539                         if (skb == frame) /* last frame */
1540                                 return RX_DROP_UNUSABLE;
1541                         dev_kfree_skb(frame);
1542                         continue;
1543                 }
1544
1545                 ieee80211_deliver_skb(rx);
1546         }
1547
1548         return RX_QUEUED;
1549 }
1550
1551 #ifdef CONFIG_MAC80211_MESH
1552 static ieee80211_rx_result
1553 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1554 {
1555         struct ieee80211_hdr *hdr;
1556         struct ieee80211s_hdr *mesh_hdr;
1557         unsigned int hdrlen;
1558         struct sk_buff *skb = rx->skb, *fwd_skb;
1559
1560         hdr = (struct ieee80211_hdr *) skb->data;
1561         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1562         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1563
1564         if (!ieee80211_is_data(hdr->frame_control))
1565                 return RX_CONTINUE;
1566
1567         if (!mesh_hdr->ttl)
1568                 /* illegal frame */
1569                 return RX_DROP_MONITOR;
1570
1571         if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6){
1572                 struct ieee80211_sub_if_data *sdata;
1573                 struct mesh_path *mppath;
1574
1575                 sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1576                 rcu_read_lock();
1577                 mppath = mpp_path_lookup(mesh_hdr->eaddr2, sdata);
1578                 if (!mppath) {
1579                         mpp_path_add(mesh_hdr->eaddr2, hdr->addr4, sdata);
1580                 } else {
1581                         spin_lock_bh(&mppath->state_lock);
1582                         mppath->exp_time = jiffies;
1583                         if (compare_ether_addr(mppath->mpp, hdr->addr4) != 0)
1584                                 memcpy(mppath->mpp, hdr->addr4, ETH_ALEN);
1585                         spin_unlock_bh(&mppath->state_lock);
1586                 }
1587                 rcu_read_unlock();
1588         }
1589
1590         if (compare_ether_addr(rx->dev->dev_addr, hdr->addr3) == 0)
1591                 return RX_CONTINUE;
1592
1593         mesh_hdr->ttl--;
1594
1595         if (rx->flags & IEEE80211_RX_RA_MATCH) {
1596                 if (!mesh_hdr->ttl)
1597                         IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1598                                                      dropped_frames_ttl);
1599                 else {
1600                         struct ieee80211_hdr *fwd_hdr;
1601                         fwd_skb = skb_copy(skb, GFP_ATOMIC);
1602
1603                         if (!fwd_skb && net_ratelimit())
1604                                 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1605                                                    rx->dev->name);
1606
1607                         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1608                         /*
1609                          * Save TA to addr1 to send TA a path error if a
1610                          * suitable next hop is not found
1611                          */
1612                         memcpy(fwd_hdr->addr1, fwd_hdr->addr2, ETH_ALEN);
1613                         memcpy(fwd_hdr->addr2, rx->dev->dev_addr, ETH_ALEN);
1614                         fwd_skb->dev = rx->local->mdev;
1615                         fwd_skb->iif = rx->dev->ifindex;
1616                         dev_queue_xmit(fwd_skb);
1617                 }
1618         }
1619
1620         if (is_multicast_ether_addr(hdr->addr3) ||
1621             rx->dev->flags & IFF_PROMISC)
1622                 return RX_CONTINUE;
1623         else
1624                 return RX_DROP_MONITOR;
1625 }
1626 #endif
1627
1628 static ieee80211_rx_result debug_noinline
1629 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1630 {
1631         struct net_device *dev = rx->dev;
1632         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1633         __le16 fc = hdr->frame_control;
1634         int err;
1635
1636         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1637                 return RX_CONTINUE;
1638
1639         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1640                 return RX_DROP_MONITOR;
1641
1642         err = ieee80211_data_to_8023(rx);
1643         if (unlikely(err))
1644                 return RX_DROP_UNUSABLE;
1645
1646         if (!ieee80211_frame_allowed(rx, fc))
1647                 return RX_DROP_MONITOR;
1648
1649         rx->skb->dev = dev;
1650
1651         dev->stats.rx_packets++;
1652         dev->stats.rx_bytes += rx->skb->len;
1653
1654         ieee80211_deliver_skb(rx);
1655
1656         return RX_QUEUED;
1657 }
1658
1659 static ieee80211_rx_result debug_noinline
1660 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
1661 {
1662         struct ieee80211_local *local = rx->local;
1663         struct ieee80211_hw *hw = &local->hw;
1664         struct sk_buff *skb = rx->skb;
1665         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1666         struct tid_ampdu_rx *tid_agg_rx;
1667         u16 start_seq_num;
1668         u16 tid;
1669
1670         if (likely(!ieee80211_is_ctl(bar->frame_control)))
1671                 return RX_CONTINUE;
1672
1673         if (ieee80211_is_back_req(bar->frame_control)) {
1674                 if (!rx->sta)
1675                         return RX_CONTINUE;
1676                 tid = le16_to_cpu(bar->control) >> 12;
1677                 if (rx->sta->ampdu_mlme.tid_state_rx[tid]
1678                                         != HT_AGG_STATE_OPERATIONAL)
1679                         return RX_CONTINUE;
1680                 tid_agg_rx = rx->sta->ampdu_mlme.tid_rx[tid];
1681
1682                 start_seq_num = le16_to_cpu(bar->start_seq_num) >> 4;
1683
1684                 /* reset session timer */
1685                 if (tid_agg_rx->timeout)
1686                         mod_timer(&tid_agg_rx->session_timer,
1687                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
1688
1689                 /* manage reordering buffer according to requested */
1690                 /* sequence number */
1691                 rcu_read_lock();
1692                 ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, NULL, NULL,
1693                                                  start_seq_num, 1);
1694                 rcu_read_unlock();
1695                 return RX_DROP_UNUSABLE;
1696         }
1697
1698         return RX_CONTINUE;
1699 }
1700
1701 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
1702                                            struct ieee80211_mgmt *mgmt,
1703                                            size_t len)
1704 {
1705         struct ieee80211_local *local = sdata->local;
1706         struct sk_buff *skb;
1707         struct ieee80211_mgmt *resp;
1708
1709         if (compare_ether_addr(mgmt->da, sdata->dev->dev_addr) != 0) {
1710                 /* Not to own unicast address */
1711                 return;
1712         }
1713
1714         if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
1715             compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
1716                 /* Not from the current AP. */
1717                 return;
1718         }
1719
1720         if (sdata->u.mgd.state == IEEE80211_STA_MLME_ASSOCIATE) {
1721                 /* Association in progress; ignore SA Query */
1722                 return;
1723         }
1724
1725         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
1726                 /* Too short SA Query request frame */
1727                 return;
1728         }
1729
1730         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
1731         if (skb == NULL)
1732                 return;
1733
1734         skb_reserve(skb, local->hw.extra_tx_headroom);
1735         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
1736         memset(resp, 0, 24);
1737         memcpy(resp->da, mgmt->sa, ETH_ALEN);
1738         memcpy(resp->sa, sdata->dev->dev_addr, ETH_ALEN);
1739         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
1740         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1741                                           IEEE80211_STYPE_ACTION);
1742         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
1743         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
1744         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
1745         memcpy(resp->u.action.u.sa_query.trans_id,
1746                mgmt->u.action.u.sa_query.trans_id,
1747                WLAN_SA_QUERY_TR_ID_LEN);
1748
1749         ieee80211_tx_skb(sdata, skb, 1);
1750 }
1751
1752 static ieee80211_rx_result debug_noinline
1753 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
1754 {
1755         struct ieee80211_local *local = rx->local;
1756         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1757         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1758         struct ieee80211_bss *bss;
1759         int len = rx->skb->len;
1760
1761         if (!ieee80211_is_action(mgmt->frame_control))
1762                 return RX_CONTINUE;
1763
1764         if (!rx->sta)
1765                 return RX_DROP_MONITOR;
1766
1767         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1768                 return RX_DROP_MONITOR;
1769
1770         if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
1771                 return RX_DROP_MONITOR;
1772
1773         /* all categories we currently handle have action_code */
1774         if (len < IEEE80211_MIN_ACTION_SIZE + 1)
1775                 return RX_DROP_MONITOR;
1776
1777         switch (mgmt->u.action.category) {
1778         case WLAN_CATEGORY_BACK:
1779                 /*
1780                  * The aggregation code is not prepared to handle
1781                  * anything but STA/AP due to the BSSID handling;
1782                  * IBSS could work in the code but isn't supported
1783                  * by drivers or the standard.
1784                  */
1785                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
1786                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
1787                     sdata->vif.type != NL80211_IFTYPE_AP)
1788                         return RX_DROP_MONITOR;
1789
1790                 switch (mgmt->u.action.u.addba_req.action_code) {
1791                 case WLAN_ACTION_ADDBA_REQ:
1792                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1793                                    sizeof(mgmt->u.action.u.addba_req)))
1794                                 return RX_DROP_MONITOR;
1795                         ieee80211_process_addba_request(local, rx->sta, mgmt, len);
1796                         break;
1797                 case WLAN_ACTION_ADDBA_RESP:
1798                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1799                                    sizeof(mgmt->u.action.u.addba_resp)))
1800                                 return RX_DROP_MONITOR;
1801                         ieee80211_process_addba_resp(local, rx->sta, mgmt, len);
1802                         break;
1803                 case WLAN_ACTION_DELBA:
1804                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1805                                    sizeof(mgmt->u.action.u.delba)))
1806                                 return RX_DROP_MONITOR;
1807                         ieee80211_process_delba(sdata, rx->sta, mgmt, len);
1808                         break;
1809                 }
1810                 break;
1811         case WLAN_CATEGORY_SPECTRUM_MGMT:
1812                 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
1813                         return RX_DROP_MONITOR;
1814
1815                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
1816                         return RX_DROP_MONITOR;
1817
1818                 switch (mgmt->u.action.u.measurement.action_code) {
1819                 case WLAN_ACTION_SPCT_MSR_REQ:
1820                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1821                                    sizeof(mgmt->u.action.u.measurement)))
1822                                 return RX_DROP_MONITOR;
1823                         ieee80211_process_measurement_req(sdata, mgmt, len);
1824                         break;
1825                 case WLAN_ACTION_SPCT_CHL_SWITCH:
1826                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1827                                    sizeof(mgmt->u.action.u.chan_switch)))
1828                                 return RX_DROP_MONITOR;
1829
1830                         if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
1831                                 return RX_DROP_MONITOR;
1832
1833                         bss = ieee80211_rx_bss_get(local, sdata->u.mgd.bssid,
1834                                            local->hw.conf.channel->center_freq,
1835                                            sdata->u.mgd.ssid,
1836                                            sdata->u.mgd.ssid_len);
1837                         if (!bss)
1838                                 return RX_DROP_MONITOR;
1839
1840                         ieee80211_process_chanswitch(sdata,
1841                                      &mgmt->u.action.u.chan_switch.sw_elem, bss);
1842                         ieee80211_rx_bss_put(local, bss);
1843                         break;
1844                 }
1845                 break;
1846         case WLAN_CATEGORY_SA_QUERY:
1847                 if (len < (IEEE80211_MIN_ACTION_SIZE +
1848                            sizeof(mgmt->u.action.u.sa_query)))
1849                         return RX_DROP_MONITOR;
1850                 switch (mgmt->u.action.u.sa_query.action) {
1851                 case WLAN_ACTION_SA_QUERY_REQUEST:
1852                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
1853                                 return RX_DROP_MONITOR;
1854                         ieee80211_process_sa_query_req(sdata, mgmt, len);
1855                         break;
1856                 case WLAN_ACTION_SA_QUERY_RESPONSE:
1857                         /*
1858                          * SA Query response is currently only used in AP mode
1859                          * and it is processed in user space.
1860                          */
1861                         return RX_CONTINUE;
1862                 }
1863                 break;
1864         default:
1865                 return RX_CONTINUE;
1866         }
1867
1868         rx->sta->rx_packets++;
1869         dev_kfree_skb(rx->skb);
1870         return RX_QUEUED;
1871 }
1872
1873 static ieee80211_rx_result debug_noinline
1874 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
1875 {
1876         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(rx->dev);
1877         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1878
1879         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1880                 return RX_DROP_MONITOR;
1881
1882         if (ieee80211_drop_unencrypted(rx, mgmt->frame_control))
1883                 return RX_DROP_MONITOR;
1884
1885         if (ieee80211_vif_is_mesh(&sdata->vif))
1886                 return ieee80211_mesh_rx_mgmt(sdata, rx->skb, rx->status);
1887
1888         if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
1889                 return ieee80211_ibss_rx_mgmt(sdata, rx->skb, rx->status);
1890
1891         if (sdata->vif.type == NL80211_IFTYPE_STATION)
1892                 return ieee80211_sta_rx_mgmt(sdata, rx->skb, rx->status);
1893
1894         return RX_DROP_MONITOR;
1895 }
1896
1897 static void ieee80211_rx_michael_mic_report(struct net_device *dev,
1898                                             struct ieee80211_hdr *hdr,
1899                                             struct ieee80211_rx_data *rx)
1900 {
1901         int keyidx;
1902         unsigned int hdrlen;
1903
1904         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1905         if (rx->skb->len >= hdrlen + 4)
1906                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
1907         else
1908                 keyidx = -1;
1909
1910         if (!rx->sta) {
1911                 /*
1912                  * Some hardware seem to generate incorrect Michael MIC
1913                  * reports; ignore them to avoid triggering countermeasures.
1914                  */
1915                 goto ignore;
1916         }
1917
1918         if (!ieee80211_has_protected(hdr->frame_control))
1919                 goto ignore;
1920
1921         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
1922                 /*
1923                  * APs with pairwise keys should never receive Michael MIC
1924                  * errors for non-zero keyidx because these are reserved for
1925                  * group keys and only the AP is sending real multicast
1926                  * frames in the BSS.
1927                  */
1928                 goto ignore;
1929         }
1930
1931         if (!ieee80211_is_data(hdr->frame_control) &&
1932             !ieee80211_is_auth(hdr->frame_control))
1933                 goto ignore;
1934
1935         mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr);
1936  ignore:
1937         dev_kfree_skb(rx->skb);
1938         rx->skb = NULL;
1939 }
1940
1941 /* TODO: use IEEE80211_RX_FRAGMENTED */
1942 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx)
1943 {
1944         struct ieee80211_sub_if_data *sdata;
1945         struct ieee80211_local *local = rx->local;
1946         struct ieee80211_rtap_hdr {
1947                 struct ieee80211_radiotap_header hdr;
1948                 u8 flags;
1949                 u8 rate;
1950                 __le16 chan_freq;
1951                 __le16 chan_flags;
1952         } __attribute__ ((packed)) *rthdr;
1953         struct sk_buff *skb = rx->skb, *skb2;
1954         struct net_device *prev_dev = NULL;
1955         struct ieee80211_rx_status *status = rx->status;
1956
1957         if (rx->flags & IEEE80211_RX_CMNTR_REPORTED)
1958                 goto out_free_skb;
1959
1960         if (skb_headroom(skb) < sizeof(*rthdr) &&
1961             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
1962                 goto out_free_skb;
1963
1964         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
1965         memset(rthdr, 0, sizeof(*rthdr));
1966         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
1967         rthdr->hdr.it_present =
1968                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
1969                             (1 << IEEE80211_RADIOTAP_RATE) |
1970                             (1 << IEEE80211_RADIOTAP_CHANNEL));
1971
1972         rthdr->rate = rx->rate->bitrate / 5;
1973         rthdr->chan_freq = cpu_to_le16(status->freq);
1974
1975         if (status->band == IEEE80211_BAND_5GHZ)
1976                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
1977                                                 IEEE80211_CHAN_5GHZ);
1978         else
1979                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
1980                                                 IEEE80211_CHAN_2GHZ);
1981
1982         skb_set_mac_header(skb, 0);
1983         skb->ip_summed = CHECKSUM_UNNECESSARY;
1984         skb->pkt_type = PACKET_OTHERHOST;
1985         skb->protocol = htons(ETH_P_802_2);
1986
1987         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
1988                 if (!netif_running(sdata->dev))
1989                         continue;
1990
1991                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
1992                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
1993                         continue;
1994
1995                 if (prev_dev) {
1996                         skb2 = skb_clone(skb, GFP_ATOMIC);
1997                         if (skb2) {
1998                                 skb2->dev = prev_dev;
1999                                 netif_rx(skb2);
2000                         }
2001                 }
2002
2003                 prev_dev = sdata->dev;
2004                 sdata->dev->stats.rx_packets++;
2005                 sdata->dev->stats.rx_bytes += skb->len;
2006         }
2007
2008         if (prev_dev) {
2009                 skb->dev = prev_dev;
2010                 netif_rx(skb);
2011                 skb = NULL;
2012         } else
2013                 goto out_free_skb;
2014
2015         rx->flags |= IEEE80211_RX_CMNTR_REPORTED;
2016         return;
2017
2018  out_free_skb:
2019         dev_kfree_skb(skb);
2020 }
2021
2022
2023 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
2024                                          struct ieee80211_rx_data *rx,
2025                                          struct sk_buff *skb)
2026 {
2027         ieee80211_rx_result res = RX_DROP_MONITOR;
2028
2029         rx->skb = skb;
2030         rx->sdata = sdata;
2031         rx->dev = sdata->dev;
2032
2033 #define CALL_RXH(rxh)                   \
2034         do {                            \
2035                 res = rxh(rx);          \
2036                 if (res != RX_CONTINUE) \
2037                         goto rxh_done;  \
2038         } while (0);
2039
2040         CALL_RXH(ieee80211_rx_h_passive_scan)
2041         CALL_RXH(ieee80211_rx_h_check)
2042         CALL_RXH(ieee80211_rx_h_decrypt)
2043         CALL_RXH(ieee80211_rx_h_check_more_data)
2044         CALL_RXH(ieee80211_rx_h_sta_process)
2045         CALL_RXH(ieee80211_rx_h_defragment)
2046         CALL_RXH(ieee80211_rx_h_ps_poll)
2047         CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2048         /* must be after MMIC verify so header is counted in MPDU mic */
2049         CALL_RXH(ieee80211_rx_h_remove_qos_control)
2050         CALL_RXH(ieee80211_rx_h_amsdu)
2051 #ifdef CONFIG_MAC80211_MESH
2052         if (ieee80211_vif_is_mesh(&sdata->vif))
2053                 CALL_RXH(ieee80211_rx_h_mesh_fwding);
2054 #endif
2055         CALL_RXH(ieee80211_rx_h_data)
2056         CALL_RXH(ieee80211_rx_h_ctrl)
2057         CALL_RXH(ieee80211_rx_h_action)
2058         CALL_RXH(ieee80211_rx_h_mgmt)
2059
2060 #undef CALL_RXH
2061
2062  rxh_done:
2063         switch (res) {
2064         case RX_DROP_MONITOR:
2065                 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2066                 if (rx->sta)
2067                         rx->sta->rx_dropped++;
2068                 /* fall through */
2069         case RX_CONTINUE:
2070                 ieee80211_rx_cooked_monitor(rx);
2071                 break;
2072         case RX_DROP_UNUSABLE:
2073                 I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2074                 if (rx->sta)
2075                         rx->sta->rx_dropped++;
2076                 dev_kfree_skb(rx->skb);
2077                 break;
2078         case RX_QUEUED:
2079                 I802_DEBUG_INC(sdata->local->rx_handlers_queued);
2080                 break;
2081         }
2082 }
2083
2084 /* main receive path */
2085
2086 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
2087                                 struct ieee80211_rx_data *rx,
2088                                 struct ieee80211_hdr *hdr)
2089 {
2090         u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len, sdata->vif.type);
2091         int multicast = is_multicast_ether_addr(hdr->addr1);
2092
2093         switch (sdata->vif.type) {
2094         case NL80211_IFTYPE_STATION:
2095                 if (!bssid)
2096                         return 0;
2097                 if (!ieee80211_bssid_match(bssid, sdata->u.mgd.bssid)) {
2098                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2099                                 return 0;
2100                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2101                 } else if (!multicast &&
2102                            compare_ether_addr(sdata->dev->dev_addr,
2103                                               hdr->addr1) != 0) {
2104                         if (!(sdata->dev->flags & IFF_PROMISC))
2105                                 return 0;
2106                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2107                 }
2108                 break;
2109         case NL80211_IFTYPE_ADHOC:
2110                 if (!bssid)
2111                         return 0;
2112                 if (ieee80211_is_beacon(hdr->frame_control)) {
2113                         return 1;
2114                 }
2115                 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2116                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2117                                 return 0;
2118                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2119                 } else if (!multicast &&
2120                            compare_ether_addr(sdata->dev->dev_addr,
2121                                               hdr->addr1) != 0) {
2122                         if (!(sdata->dev->flags & IFF_PROMISC))
2123                                 return 0;
2124                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2125                 } else if (!rx->sta) {
2126                         int rate_idx;
2127                         if (rx->status->flag & RX_FLAG_HT)
2128                                 rate_idx = 0; /* TODO: HT rates */
2129                         else
2130                                 rate_idx = rx->status->rate_idx;
2131                         rx->sta = ieee80211_ibss_add_sta(sdata, bssid, hdr->addr2,
2132                                 BIT(rate_idx));
2133                 }
2134                 break;
2135         case NL80211_IFTYPE_MESH_POINT:
2136                 if (!multicast &&
2137                     compare_ether_addr(sdata->dev->dev_addr,
2138                                        hdr->addr1) != 0) {
2139                         if (!(sdata->dev->flags & IFF_PROMISC))
2140                                 return 0;
2141
2142                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2143                 }
2144                 break;
2145         case NL80211_IFTYPE_AP_VLAN:
2146         case NL80211_IFTYPE_AP:
2147                 if (!bssid) {
2148                         if (compare_ether_addr(sdata->dev->dev_addr,
2149                                                hdr->addr1))
2150                                 return 0;
2151                 } else if (!ieee80211_bssid_match(bssid,
2152                                         sdata->dev->dev_addr)) {
2153                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2154                                 return 0;
2155                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2156                 }
2157                 break;
2158         case NL80211_IFTYPE_WDS:
2159                 if (bssid || !ieee80211_is_data(hdr->frame_control))
2160                         return 0;
2161                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2162                         return 0;
2163                 break;
2164         case NL80211_IFTYPE_MONITOR:
2165                 /* take everything */
2166                 break;
2167         case NL80211_IFTYPE_UNSPECIFIED:
2168         case __NL80211_IFTYPE_AFTER_LAST:
2169                 /* should never get here */
2170                 WARN_ON(1);
2171                 break;
2172         }
2173
2174         return 1;
2175 }
2176
2177 /*
2178  * This is the actual Rx frames handler. as it blongs to Rx path it must
2179  * be called with rcu_read_lock protection.
2180  */
2181 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2182                                          struct sk_buff *skb,
2183                                          struct ieee80211_rx_status *status,
2184                                          struct ieee80211_rate *rate)
2185 {
2186         struct ieee80211_local *local = hw_to_local(hw);
2187         struct ieee80211_sub_if_data *sdata;
2188         struct ieee80211_hdr *hdr;
2189         struct ieee80211_rx_data rx;
2190         int prepares;
2191         struct ieee80211_sub_if_data *prev = NULL;
2192         struct sk_buff *skb_new;
2193
2194         hdr = (struct ieee80211_hdr *)skb->data;
2195         memset(&rx, 0, sizeof(rx));
2196         rx.skb = skb;
2197         rx.local = local;
2198
2199         rx.status = status;
2200         rx.rate = rate;
2201
2202         if (ieee80211_is_data(hdr->frame_control) || ieee80211_is_mgmt(hdr->frame_control))
2203                 local->dot11ReceivedFragmentCount++;
2204
2205         rx.sta = sta_info_get(local, hdr->addr2);
2206         if (rx.sta) {
2207                 rx.sdata = rx.sta->sdata;
2208                 rx.dev = rx.sta->sdata->dev;
2209         }
2210
2211         if ((status->flag & RX_FLAG_MMIC_ERROR)) {
2212                 ieee80211_rx_michael_mic_report(local->mdev, hdr, &rx);
2213                 return;
2214         }
2215
2216         if (unlikely(local->sw_scanning || local->hw_scanning))
2217                 rx.flags |= IEEE80211_RX_IN_SCAN;
2218
2219         ieee80211_parse_qos(&rx);
2220         ieee80211_verify_alignment(&rx);
2221
2222         skb = rx.skb;
2223
2224         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2225                 if (!netif_running(sdata->dev))
2226                         continue;
2227
2228                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR)
2229                         continue;
2230
2231                 rx.flags |= IEEE80211_RX_RA_MATCH;
2232                 prepares = prepare_for_handlers(sdata, &rx, hdr);
2233
2234                 if (!prepares)
2235                         continue;
2236
2237                 /*
2238                  * frame is destined for this interface, but if it's not
2239                  * also for the previous one we handle that after the
2240                  * loop to avoid copying the SKB once too much
2241                  */
2242
2243                 if (!prev) {
2244                         prev = sdata;
2245                         continue;
2246                 }
2247
2248                 /*
2249                  * frame was destined for the previous interface
2250                  * so invoke RX handlers for it
2251                  */
2252
2253                 skb_new = skb_copy(skb, GFP_ATOMIC);
2254                 if (!skb_new) {
2255                         if (net_ratelimit())
2256                                 printk(KERN_DEBUG "%s: failed to copy "
2257                                        "multicast frame for %s\n",
2258                                        wiphy_name(local->hw.wiphy),
2259                                        prev->dev->name);
2260                         continue;
2261                 }
2262                 ieee80211_invoke_rx_handlers(prev, &rx, skb_new);
2263                 prev = sdata;
2264         }
2265         if (prev)
2266                 ieee80211_invoke_rx_handlers(prev, &rx, skb);
2267         else
2268                 dev_kfree_skb(skb);
2269 }
2270
2271 #define SEQ_MODULO 0x1000
2272 #define SEQ_MASK   0xfff
2273
2274 static inline int seq_less(u16 sq1, u16 sq2)
2275 {
2276         return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
2277 }
2278
2279 static inline u16 seq_inc(u16 sq)
2280 {
2281         return (sq + 1) & SEQ_MASK;
2282 }
2283
2284 static inline u16 seq_sub(u16 sq1, u16 sq2)
2285 {
2286         return (sq1 - sq2) & SEQ_MASK;
2287 }
2288
2289
2290 /*
2291  * As it function blongs to Rx path it must be called with
2292  * the proper rcu_read_lock protection for its flow.
2293  */
2294 static u8 ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
2295                                            struct tid_ampdu_rx *tid_agg_rx,
2296                                            struct sk_buff *skb,
2297                                            struct ieee80211_rx_status *rxstatus,
2298                                            u16 mpdu_seq_num,
2299                                            int bar_req)
2300 {
2301         struct ieee80211_local *local = hw_to_local(hw);
2302         struct ieee80211_rx_status status;
2303         u16 head_seq_num, buf_size;
2304         int index;
2305         struct ieee80211_supported_band *sband;
2306         struct ieee80211_rate *rate;
2307
2308         buf_size = tid_agg_rx->buf_size;
2309         head_seq_num = tid_agg_rx->head_seq_num;
2310
2311         /* frame with out of date sequence number */
2312         if (seq_less(mpdu_seq_num, head_seq_num)) {
2313                 dev_kfree_skb(skb);
2314                 return 1;
2315         }
2316
2317         /* if frame sequence number exceeds our buffering window size or
2318          * block Ack Request arrived - release stored frames */
2319         if ((!seq_less(mpdu_seq_num, head_seq_num + buf_size)) || (bar_req)) {
2320                 /* new head to the ordering buffer */
2321                 if (bar_req)
2322                         head_seq_num = mpdu_seq_num;
2323                 else
2324                         head_seq_num =
2325                                 seq_inc(seq_sub(mpdu_seq_num, buf_size));
2326                 /* release stored frames up to new head to stack */
2327                 while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
2328                         index = seq_sub(tid_agg_rx->head_seq_num,
2329                                 tid_agg_rx->ssn)
2330                                 % tid_agg_rx->buf_size;
2331
2332                         if (tid_agg_rx->reorder_buf[index]) {
2333                                 /* release the reordered frames to stack */
2334                                 memcpy(&status,
2335                                         tid_agg_rx->reorder_buf[index]->cb,
2336                                         sizeof(status));
2337                                 sband = local->hw.wiphy->bands[status.band];
2338                                 if (status.flag & RX_FLAG_HT) {
2339                                         /* TODO: HT rates */
2340                                         rate = sband->bitrates;
2341                                 } else {
2342                                         rate = &sband->bitrates
2343                                                 [status.rate_idx];
2344                                 }
2345                                 __ieee80211_rx_handle_packet(hw,
2346                                         tid_agg_rx->reorder_buf[index],
2347                                         &status, rate);
2348                                 tid_agg_rx->stored_mpdu_num--;
2349                                 tid_agg_rx->reorder_buf[index] = NULL;
2350                         }
2351                         tid_agg_rx->head_seq_num =
2352                                 seq_inc(tid_agg_rx->head_seq_num);
2353                 }
2354                 if (bar_req)
2355                         return 1;
2356         }
2357
2358         /* now the new frame is always in the range of the reordering */
2359         /* buffer window */
2360         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn)
2361                                 % tid_agg_rx->buf_size;
2362         /* check if we already stored this frame */
2363         if (tid_agg_rx->reorder_buf[index]) {
2364                 dev_kfree_skb(skb);
2365                 return 1;
2366         }
2367
2368         /* if arrived mpdu is in the right order and nothing else stored */
2369         /* release it immediately */
2370         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
2371                         tid_agg_rx->stored_mpdu_num == 0) {
2372                 tid_agg_rx->head_seq_num =
2373                         seq_inc(tid_agg_rx->head_seq_num);
2374                 return 0;
2375         }
2376
2377         /* put the frame in the reordering buffer */
2378         tid_agg_rx->reorder_buf[index] = skb;
2379         memcpy(tid_agg_rx->reorder_buf[index]->cb, rxstatus,
2380                sizeof(*rxstatus));
2381         tid_agg_rx->stored_mpdu_num++;
2382         /* release the buffer until next missing frame */
2383         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn)
2384                                                 % tid_agg_rx->buf_size;
2385         while (tid_agg_rx->reorder_buf[index]) {
2386                 /* release the reordered frame back to stack */
2387                 memcpy(&status, tid_agg_rx->reorder_buf[index]->cb,
2388                         sizeof(status));
2389                 sband = local->hw.wiphy->bands[status.band];
2390                 if (status.flag & RX_FLAG_HT)
2391                         rate = sband->bitrates; /* TODO: HT rates */
2392                 else
2393                         rate = &sband->bitrates[status.rate_idx];
2394                 __ieee80211_rx_handle_packet(hw, tid_agg_rx->reorder_buf[index],
2395                                              &status, rate);
2396                 tid_agg_rx->stored_mpdu_num--;
2397                 tid_agg_rx->reorder_buf[index] = NULL;
2398                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
2399                 index = seq_sub(tid_agg_rx->head_seq_num,
2400                         tid_agg_rx->ssn) % tid_agg_rx->buf_size;
2401         }
2402         return 1;
2403 }
2404
2405 static u8 ieee80211_rx_reorder_ampdu(struct ieee80211_local *local,
2406                                      struct sk_buff *skb,
2407                                      struct ieee80211_rx_status *status)
2408 {
2409         struct ieee80211_hw *hw = &local->hw;
2410         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
2411         struct sta_info *sta;
2412         struct tid_ampdu_rx *tid_agg_rx;
2413         u16 sc;
2414         u16 mpdu_seq_num;
2415         u8 ret = 0;
2416         int tid;
2417
2418         sta = sta_info_get(local, hdr->addr2);
2419         if (!sta)
2420                 return ret;
2421
2422         /* filter the QoS data rx stream according to
2423          * STA/TID and check if this STA/TID is on aggregation */
2424         if (!ieee80211_is_data_qos(hdr->frame_control))
2425                 goto end_reorder;
2426
2427         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
2428
2429         if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL)
2430                 goto end_reorder;
2431
2432         tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
2433
2434         /* qos null data frames are excluded */
2435         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
2436                 goto end_reorder;
2437
2438         /* new un-ordered ampdu frame - process it */
2439
2440         /* reset session timer */
2441         if (tid_agg_rx->timeout)
2442                 mod_timer(&tid_agg_rx->session_timer,
2443                           TU_TO_EXP_TIME(tid_agg_rx->timeout));
2444
2445         /* if this mpdu is fragmented - terminate rx aggregation session */
2446         sc = le16_to_cpu(hdr->seq_ctrl);
2447         if (sc & IEEE80211_SCTL_FRAG) {
2448                 ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
2449                         tid, 0, WLAN_REASON_QSTA_REQUIRE_SETUP);
2450                 ret = 1;
2451                 goto end_reorder;
2452         }
2453
2454         /* according to mpdu sequence number deal with reordering buffer */
2455         mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
2456         ret = ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb, status,
2457                                                 mpdu_seq_num, 0);
2458  end_reorder:
2459         return ret;
2460 }
2461
2462 /*
2463  * This is the receive path handler. It is called by a low level driver when an
2464  * 802.11 MPDU is received from the hardware.
2465  */
2466 void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb,
2467                     struct ieee80211_rx_status *status)
2468 {
2469         struct ieee80211_local *local = hw_to_local(hw);
2470         struct ieee80211_rate *rate = NULL;
2471         struct ieee80211_supported_band *sband;
2472
2473         if (status->band < 0 ||
2474             status->band >= IEEE80211_NUM_BANDS) {
2475                 WARN_ON(1);
2476                 return;
2477         }
2478
2479         sband = local->hw.wiphy->bands[status->band];
2480         if (!sband) {
2481                 WARN_ON(1);
2482                 return;
2483         }
2484
2485         if (status->flag & RX_FLAG_HT) {
2486                 /* rate_idx is MCS index */
2487                 if (WARN_ON(status->rate_idx < 0 ||
2488                             status->rate_idx >= 76))
2489                         return;
2490                 /* HT rates are not in the table - use the highest legacy rate
2491                  * for now since other parts of mac80211 may not yet be fully
2492                  * MCS aware. */
2493                 rate = &sband->bitrates[sband->n_bitrates - 1];
2494         } else {
2495                 if (WARN_ON(status->rate_idx < 0 ||
2496                             status->rate_idx >= sband->n_bitrates))
2497                         return;
2498                 rate = &sband->bitrates[status->rate_idx];
2499         }
2500
2501         /*
2502          * key references and virtual interfaces are protected using RCU
2503          * and this requires that we are in a read-side RCU section during
2504          * receive processing
2505          */
2506         rcu_read_lock();
2507
2508         /*
2509          * Frames with failed FCS/PLCP checksum are not returned,
2510          * all other frames are returned without radiotap header
2511          * if it was previously present.
2512          * Also, frames with less than 16 bytes are dropped.
2513          */
2514         skb = ieee80211_rx_monitor(local, skb, status, rate);
2515         if (!skb) {
2516                 rcu_read_unlock();
2517                 return;
2518         }
2519
2520         if (!ieee80211_rx_reorder_ampdu(local, skb, status))
2521                 __ieee80211_rx_handle_packet(hw, skb, status, rate);
2522
2523         rcu_read_unlock();
2524 }
2525 EXPORT_SYMBOL(__ieee80211_rx);
2526
2527 /* This is a version of the rx handler that can be called from hard irq
2528  * context. Post the skb on the queue and schedule the tasklet */
2529 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb,
2530                           struct ieee80211_rx_status *status)
2531 {
2532         struct ieee80211_local *local = hw_to_local(hw);
2533
2534         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2535
2536         skb->dev = local->mdev;
2537         /* copy status into skb->cb for use by tasklet */
2538         memcpy(skb->cb, status, sizeof(*status));
2539         skb->pkt_type = IEEE80211_RX_MSG;
2540         skb_queue_tail(&local->skb_queue, skb);
2541         tasklet_schedule(&local->tasklet);
2542 }
2543 EXPORT_SYMBOL(ieee80211_rx_irqsafe);