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 2007-2010  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/slab.h>
  14 #include <linux/kernel.h>
  15 #include <linux/skbuff.h>
  16 #include <linux/netdevice.h>
  17 #include <linux/etherdevice.h>
  18 #include <linux/rcupdate.h>
  19 #include <net/mac80211.h>
  20 #include <net/ieee80211_radiotap.h>
  21
  22 #include "ieee80211_i.h"
  23 #include "driver-ops.h"
  24 #include "led.h"
  25 #include "mesh.h"
  26 #include "wep.h"
  27 #include "wpa.h"
  28 #include "tkip.h"
  29 #include "wme.h"
  30
  31 /*
  32  * monitor mode reception
  33  *
  34  * This function cleans up the SKB, i.e. it removes all the stuff
  35  * only useful for monitoring.
  36  */
  37 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
  38                                            struct sk_buff *skb)
  39 {
  40         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
  41                 if (likely(skb->len > FCS_LEN))
  42                         __pskb_trim(skb, skb->len - FCS_LEN);
  43                 else {
  44                         /* driver bug */
  45                         WARN_ON(1);
  46                         dev_kfree_skb(skb);
  47                         skb = NULL;
  48                 }
  49         }
  50
  51         return skb;
  52 }
  53
  54 static inline int should_drop_frame(struct sk_buff *skb,
  55                                     int present_fcs_len)
  56 {
  57         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  58         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  59
  60         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
  61                 return 1;
  62         if (unlikely(skb->len < 16 + present_fcs_len))
  63                 return 1;
  64         if (ieee80211_is_ctl(hdr->frame_control) &&
  65             !ieee80211_is_pspoll(hdr->frame_control) &&
  66             !ieee80211_is_back_req(hdr->frame_control))
  67                 return 1;
  68         return 0;
  69 }
  70
  71 static int
  72 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
  73                           struct ieee80211_rx_status *status)
  74 {
  75         int len;
  76
  77         /* always present fields */
  78         len = sizeof(struct ieee80211_radiotap_header) + 9;
  79
  80         if (status->flag & RX_FLAG_TSFT)
  81                 len += 8;
  82         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
  83                 len += 1;
  84
  85         if (len & 1) /* padding for RX_FLAGS if necessary */
  86                 len++;
  87
  88         return len;
  89 }
  90
  91 /*
  92  * ieee80211_add_rx_radiotap_header - add radiotap header
  93  *
  94  * add a radiotap header containing all the fields which the hardware provided.
  95  */
  96 static void
  97 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
  98                                  struct sk_buff *skb,
  99                                  struct ieee80211_rate *rate,
 100                                  int rtap_len)
 101 {
 102         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 103         struct ieee80211_radiotap_header *rthdr;
 104         unsigned char *pos;
 105         u16 rx_flags = 0;
 106
 107         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
 108         memset(rthdr, 0, rtap_len);
 109
 110         /* radiotap header, set always present flags */
 111         rthdr->it_present =
 112                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 113                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
 114                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
 115                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
 116         rthdr->it_len = cpu_to_le16(rtap_len);
 117
 118         pos = (unsigned char *)(rthdr+1);
 119
 120         /* the order of the following fields is important */
 121
 122         /* IEEE80211_RADIOTAP_TSFT */
 123         if (status->flag & RX_FLAG_TSFT) {
 124                 put_unaligned_le64(status->mactime, pos);
 125                 rthdr->it_present |=
 126                         cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
 127                 pos += 8;
 128         }
 129
 130         /* IEEE80211_RADIOTAP_FLAGS */
 131         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 132                 *pos |= IEEE80211_RADIOTAP_F_FCS;
 133         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 134                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
 135         if (status->flag & RX_FLAG_SHORTPRE)
 136                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
 137         pos++;
 138
 139         /* IEEE80211_RADIOTAP_RATE */
 140         if (status->flag & RX_FLAG_HT) {
 141                 /*
 142                  * TODO: add following information into radiotap header once
 143                  * suitable fields are defined for it:
 144                  * - MCS index (status->rate_idx)
 145                  * - HT40 (status->flag & RX_FLAG_40MHZ)
 146                  * - short-GI (status->flag & RX_FLAG_SHORT_GI)
 147                  */
 148                 *pos = 0;
 149         } else {
 150                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
 151                 *pos = rate->bitrate / 5;
 152         }
 153         pos++;
 154
 155         /* IEEE80211_RADIOTAP_CHANNEL */
 156         put_unaligned_le16(status->freq, pos);
 157         pos += 2;
 158         if (status->band == IEEE80211_BAND_5GHZ)
 159                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
 160                                    pos);
 161         else if (status->flag & RX_FLAG_HT)
 162                 put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ,
 163                                    pos);
 164         else if (rate->flags & IEEE80211_RATE_ERP_G)
 165                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
 166                                    pos);
 167         else
 168                 put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
 169                                    pos);
 170         pos += 2;
 171
 172         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
 173         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
 174                 *pos = status->signal;
 175                 rthdr->it_present |=
 176                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
 177                 pos++;
 178         }
 179
 180         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
 181
 182         /* IEEE80211_RADIOTAP_ANTENNA */
 183         *pos = status->antenna;
 184         pos++;
 185
 186         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
 187
 188         /* IEEE80211_RADIOTAP_RX_FLAGS */
 189         /* ensure 2 byte alignment for the 2 byte field as required */
 190         if ((pos - (u8 *)rthdr) & 1)
 191                 pos++;
 192         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
 193                 rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
 194         put_unaligned_le16(rx_flags, pos);
 195         pos += 2;
 196 }
 197
 198 /*
 199  * This function copies a received frame to all monitor interfaces and
 200  * returns a cleaned-up SKB that no longer includes the FCS nor the
 201  * radiotap header the driver might have added.
 202  */
 203 static struct sk_buff *
 204 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
 205                      struct ieee80211_rate *rate)
 206 {
 207         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
 208         struct ieee80211_sub_if_data *sdata;
 209         int needed_headroom = 0;
 210         struct sk_buff *skb, *skb2;
 211         struct net_device *prev_dev = NULL;
 212         int present_fcs_len = 0;
 213
 214         /*
 215          * First, we may need to make a copy of the skb because
 216          *  (1) we need to modify it for radiotap (if not present), and
 217          *  (2) the other RX handlers will modify the skb we got.
 218          *
 219          * We don't need to, of course, if we aren't going to return
 220          * the SKB because it has a bad FCS/PLCP checksum.
 221          */
 222
 223         /* room for the radiotap header based on driver features */
 224         needed_headroom = ieee80211_rx_radiotap_len(local, status);
 225
 226         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 227                 present_fcs_len = FCS_LEN;
 228
 229         /* make sure hdr->frame_control is on the linear part */
 230         if (!pskb_may_pull(origskb, 2)) {
 231                 dev_kfree_skb(origskb);
 232                 return NULL;
 233         }
 234
 235         if (!local->monitors) {
 236                 if (should_drop_frame(origskb, present_fcs_len)) {
 237                         dev_kfree_skb(origskb);
 238                         return NULL;
 239                 }
 240
 241                 return remove_monitor_info(local, origskb);
 242         }
 243
 244         if (should_drop_frame(origskb, present_fcs_len)) {
 245                 /* only need to expand headroom if necessary */
 246                 skb = origskb;
 247                 origskb = NULL;
 248
 249                 /*
 250                  * This shouldn't trigger often because most devices have an
 251                  * RX header they pull before we get here, and that should
 252                  * be big enough for our radiotap information. We should
 253                  * probably export the length to drivers so that we can have
 254                  * them allocate enough headroom to start with.
 255                  */
 256                 if (skb_headroom(skb) < needed_headroom &&
 257                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
 258                         dev_kfree_skb(skb);
 259                         return NULL;
 260                 }
 261         } else {
 262                 /*
 263                  * Need to make a copy and possibly remove radiotap header
 264                  * and FCS from the original.
 265                  */
 266                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
 267
 268                 origskb = remove_monitor_info(local, origskb);
 269
 270                 if (!skb)
 271                         return origskb;
 272         }
 273
 274         /* prepend radiotap information */
 275         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom);
 276
 277         skb_reset_mac_header(skb);
 278         skb->ip_summed = CHECKSUM_UNNECESSARY;
 279         skb->pkt_type = PACKET_OTHERHOST;
 280         skb->protocol = htons(ETH_P_802_2);
 281
 282         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 283                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
 284                         continue;
 285
 286                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
 287                         continue;
 288
 289                 if (!ieee80211_sdata_running(sdata))
 290                         continue;
 291
 292                 if (prev_dev) {
 293                         skb2 = skb_clone(skb, GFP_ATOMIC);
 294                         if (skb2) {
 295                                 skb2->dev = prev_dev;
 296                                 netif_rx(skb2);
 297                         }
 298                 }
 299
 300                 prev_dev = sdata->dev;
 301                 sdata->dev->stats.rx_packets++;
 302                 sdata->dev->stats.rx_bytes += skb->len;
 303         }
 304
 305         if (prev_dev) {
 306                 skb->dev = prev_dev;
 307                 netif_rx(skb);
 308         } else
 309                 dev_kfree_skb(skb);
 310
 311         return origskb;
 312 }
 313
 314
 315 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
 316 {
 317         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 318         int tid;
 319
 320         /* does the frame have a qos control field? */
 321         if (ieee80211_is_data_qos(hdr->frame_control)) {
 322                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 323                 /* frame has qos control */
 324                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
 325                 if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT)
 326                         rx->flags |= IEEE80211_RX_AMSDU;
 327                 else
 328                         rx->flags &= ~IEEE80211_RX_AMSDU;
 329         } else {
 330                 /*
 331                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
 332                  *
 333                  *      Sequence numbers for management frames, QoS data
 334                  *      frames with a broadcast/multicast address in the
 335                  *      Address 1 field, and all non-QoS data frames sent
 336                  *      by QoS STAs are assigned using an additional single
 337                  *      modulo-4096 counter, [...]
 338                  *
 339                  * We also use that counter for non-QoS STAs.
 340                  */
 341                 tid = NUM_RX_DATA_QUEUES - 1;
 342         }
 343
 344         rx->queue = tid;
 345         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 346          * For now, set skb->priority to 0 for other cases. */
 347         rx->skb->priority = (tid > 7) ? 0 : tid;
 348 }
 349
 350 /**
 351  * DOC: Packet alignment
 352  *
 353  * Drivers always need to pass packets that are aligned to two-byte boundaries
 354  * to the stack.
 355  *
 356  * Additionally, should, if possible, align the payload data in a way that
 357  * guarantees that the contained IP header is aligned to a four-byte
 358  * boundary. In the case of regular frames, this simply means aligning the
 359  * payload to a four-byte boundary (because either the IP header is directly
 360  * contained, or IV/RFC1042 headers that have a length divisible by four are
 361  * in front of it).  If the payload data is not properly aligned and the
 362  * architecture doesn't support efficient unaligned operations, mac80211
 363  * will align the data.
 364  *
 365  * With A-MSDU frames, however, the payload data address must yield two modulo
 366  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
 367  * push the IP header further back to a multiple of four again. Thankfully, the
 368  * specs were sane enough this time around to require padding each A-MSDU
 369  * subframe to a length that is a multiple of four.
 370  *
 371  * Padding like Atheros hardware adds which is inbetween the 802.11 header and
 372  * the payload is not supported, the driver is required to move the 802.11
 373  * header to be directly in front of the payload in that case.
 374  */
 375 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
 376 {
 377 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 378         WARN_ONCE((unsigned long)rx->skb->data & 1,
 379                   "unaligned packet at 0x%p\n", rx->skb->data);
 380 #endif
 381 }
 382
 383
 384 /* rx handlers */
 385
 386 static ieee80211_rx_result debug_noinline
 387 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
 388 {
 389         struct ieee80211_local *local = rx->local;
 390         struct sk_buff *skb = rx->skb;
 391
 392         if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning)))
 393                 return ieee80211_scan_rx(rx->sdata, skb);
 394
 395         if (unlikely(test_bit(SCAN_SW_SCANNING, &local->scanning) &&
 396                      (rx->flags & IEEE80211_RX_IN_SCAN))) {
 397                 /* drop all the other packets during a software scan anyway */
 398                 if (ieee80211_scan_rx(rx->sdata, skb) != RX_QUEUED)
 399                         dev_kfree_skb(skb);
 400                 return RX_QUEUED;
 401         }
 402
 403         if (unlikely(rx->flags & IEEE80211_RX_IN_SCAN)) {
 404                 /* scanning finished during invoking of handlers */
 405                 I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
 406                 return RX_DROP_UNUSABLE;
 407         }
 408
 409         return RX_CONTINUE;
 410 }
 411
 412
 413 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
 414 {
 415         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 416
 417         if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
 418                 return 0;
 419
 420         return ieee80211_is_robust_mgmt_frame(hdr);
 421 }
 422
 423
 424 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
 425 {
 426         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 427
 428         if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
 429                 return 0;
 430
 431         return ieee80211_is_robust_mgmt_frame(hdr);
 432 }
 433
 434
 435 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
 436 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
 437 {
 438         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
 439         struct ieee80211_mmie *mmie;
 440
 441         if (skb->len < 24 + sizeof(*mmie) ||
 442             !is_multicast_ether_addr(hdr->da))
 443                 return -1;
 444
 445         if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
 446                 return -1; /* not a robust management frame */
 447
 448         mmie = (struct ieee80211_mmie *)
 449                 (skb->data + skb->len - sizeof(*mmie));
 450         if (mmie->element_id != WLAN_EID_MMIE ||
 451             mmie->length != sizeof(*mmie) - 2)
 452                 return -1;
 453
 454         return le16_to_cpu(mmie->key_id);
 455 }
 456
 457
 458 static ieee80211_rx_result
 459 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
 460 {
 461         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 462         unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
 463         char *dev_addr = rx->sdata->vif.addr;
 464
 465         if (ieee80211_is_data(hdr->frame_control)) {
 466                 if (is_multicast_ether_addr(hdr->addr1)) {
 467                         if (ieee80211_has_tods(hdr->frame_control) ||
 468                                 !ieee80211_has_fromds(hdr->frame_control))
 469                                 return RX_DROP_MONITOR;
 470                         if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0)
 471                                 return RX_DROP_MONITOR;
 472                 } else {
 473                         if (!ieee80211_has_a4(hdr->frame_control))
 474                                 return RX_DROP_MONITOR;
 475                         if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0)
 476                                 return RX_DROP_MONITOR;
 477                 }
 478         }
 479
 480         /* If there is not an established peer link and this is not a peer link
 481          * establisment frame, beacon or probe, drop the frame.
 482          */
 483
 484         if (!rx->sta || sta_plink_state(rx->sta) != PLINK_ESTAB) {
 485                 struct ieee80211_mgmt *mgmt;
 486
 487                 if (!ieee80211_is_mgmt(hdr->frame_control))
 488                         return RX_DROP_MONITOR;
 489
 490                 if (ieee80211_is_action(hdr->frame_control)) {
 491                         mgmt = (struct ieee80211_mgmt *)hdr;
 492                         if (mgmt->u.action.category != WLAN_CATEGORY_MESH_PLINK)
 493                                 return RX_DROP_MONITOR;
 494                         return RX_CONTINUE;
 495                 }
 496
 497                 if (ieee80211_is_probe_req(hdr->frame_control) ||
 498                     ieee80211_is_probe_resp(hdr->frame_control) ||
 499                     ieee80211_is_beacon(hdr->frame_control))
 500                         return RX_CONTINUE;
 501
 502                 return RX_DROP_MONITOR;
 503
 504         }
 505
 506 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
 507
 508         if (ieee80211_is_data(hdr->frame_control) &&
 509             is_multicast_ether_addr(hdr->addr1) &&
 510             mesh_rmc_check(hdr->addr3, msh_h_get(hdr, hdrlen), rx->sdata))
 511                 return RX_DROP_MONITOR;
 512 #undef msh_h_get
 513
 514         return RX_CONTINUE;
 515 }
 516
 517 #define SEQ_MODULO 0x1000
 518 #define SEQ_MASK   0xfff
 519
 520 static inline int seq_less(u16 sq1, u16 sq2)
 521 {
 522         return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
 523 }
 524
 525 static inline u16 seq_inc(u16 sq)
 526 {
 527         return (sq + 1) & SEQ_MASK;
 528 }
 529
 530 static inline u16 seq_sub(u16 sq1, u16 sq2)
 531 {
 532         return (sq1 - sq2) & SEQ_MASK;
 533 }
 534
 535
 536 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
 537                                             struct tid_ampdu_rx *tid_agg_rx,
 538                                             int index,
 539                                             struct sk_buff_head *frames)
 540 {
 541         struct ieee80211_supported_band *sband;
 542         struct ieee80211_rate *rate = NULL;
 543         struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
 544         struct ieee80211_rx_status *status;
 545
 546         if (!skb)
 547                 goto no_frame;
 548
 549         status = IEEE80211_SKB_RXCB(skb);
 550
 551         /* release the reordered frames to stack */
 552         sband = hw->wiphy->bands[status->band];
 553         if (!(status->flag & RX_FLAG_HT))
 554                 rate = &sband->bitrates[status->rate_idx];
 555         tid_agg_rx->stored_mpdu_num--;
 556         tid_agg_rx->reorder_buf[index] = NULL;
 557         __skb_queue_tail(frames, skb);
 558
 559 no_frame:
 560         tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
 561 }
 562
 563 static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw,
 564                                              struct tid_ampdu_rx *tid_agg_rx,
 565                                              u16 head_seq_num,
 566                                              struct sk_buff_head *frames)
 567 {
 568         int index;
 569
 570         while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
 571                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
 572                                                         tid_agg_rx->buf_size;
 573                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames);
 574         }
 575 }
 576
 577 /*
 578  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
 579  * the skb was added to the buffer longer than this time ago, the earlier
 580  * frames that have not yet been received are assumed to be lost and the skb
 581  * can be released for processing. This may also release other skb's from the
 582  * reorder buffer if there are no additional gaps between the frames.
 583  */
 584 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
 585
 586 /*
 587  * As this function belongs to the RX path it must be under
 588  * rcu_read_lock protection. It returns false if the frame
 589  * can be processed immediately, true if it was consumed.
 590  */
 591 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
 592                                              struct tid_ampdu_rx *tid_agg_rx,
 593                                              struct sk_buff *skb,
 594                                              struct sk_buff_head *frames)
 595 {
 596         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 597         u16 sc = le16_to_cpu(hdr->seq_ctrl);
 598         u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
 599         u16 head_seq_num, buf_size;
 600         int index;
 601
 602         buf_size = tid_agg_rx->buf_size;
 603         head_seq_num = tid_agg_rx->head_seq_num;
 604
 605         /* frame with out of date sequence number */
 606         if (seq_less(mpdu_seq_num, head_seq_num)) {
 607                 dev_kfree_skb(skb);
 608                 return true;
 609         }
 610
 611         /*
 612          * If frame the sequence number exceeds our buffering window
 613          * size release some previous frames to make room for this one.
 614          */
 615         if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
 616                 head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
 617                 /* release stored frames up to new head to stack */
 618                 ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num,
 619                                                  frames);
 620         }
 621
 622         /* Now the new frame is always in the range of the reordering buffer */
 623
 624         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size;
 625
 626         /* check if we already stored this frame */
 627         if (tid_agg_rx->reorder_buf[index]) {
 628                 dev_kfree_skb(skb);
 629                 return true;
 630         }
 631
 632         /*
 633          * If the current MPDU is in the right order and nothing else
 634          * is stored we can process it directly, no need to buffer it.
 635          */
 636         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
 637             tid_agg_rx->stored_mpdu_num == 0) {
 638                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
 639                 return false;
 640         }
 641
 642         /* put the frame in the reordering buffer */
 643         tid_agg_rx->reorder_buf[index] = skb;
 644         tid_agg_rx->reorder_time[index] = jiffies;
 645         tid_agg_rx->stored_mpdu_num++;
 646         /* release the buffer until next missing frame */
 647         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
 648                                                 tid_agg_rx->buf_size;
 649         if (!tid_agg_rx->reorder_buf[index] &&
 650             tid_agg_rx->stored_mpdu_num > 1) {
 651                 /*
 652                  * No buffers ready to be released, but check whether any
 653                  * frames in the reorder buffer have timed out.
 654                  */
 655                 int j;
 656                 int skipped = 1;
 657                 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
 658                      j = (j + 1) % tid_agg_rx->buf_size) {
 659                         if (!tid_agg_rx->reorder_buf[j]) {
 660                                 skipped++;
 661                                 continue;
 662                         }
 663                         if (!time_after(jiffies, tid_agg_rx->reorder_time[j] +
 664                                         HT_RX_REORDER_BUF_TIMEOUT))
 665                                 break;
 666
 667 #ifdef CONFIG_MAC80211_HT_DEBUG
 668                         if (net_ratelimit())
 669                                 printk(KERN_DEBUG "%s: release an RX reorder "
 670                                        "frame due to timeout on earlier "
 671                                        "frames\n",
 672                                        wiphy_name(hw->wiphy));
 673 #endif
 674                         ieee80211_release_reorder_frame(hw, tid_agg_rx,
 675                                                         j, frames);
 676
 677                         /*
 678                          * Increment the head seq# also for the skipped slots.
 679                          */
 680                         tid_agg_rx->head_seq_num =
 681                                 (tid_agg_rx->head_seq_num + skipped) & SEQ_MASK;
 682                         skipped = 0;
 683                 }
 684         } else while (tid_agg_rx->reorder_buf[index]) {
 685                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames);
 686                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
 687                                                         tid_agg_rx->buf_size;
 688         }
 689
 690         return true;
 691 }
 692
 693 /*
 694  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
 695  * true if the MPDU was buffered, false if it should be processed.
 696  */
 697 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
 698                                        struct sk_buff_head *frames)
 699 {
 700         struct sk_buff *skb = rx->skb;
 701         struct ieee80211_local *local = rx->local;
 702         struct ieee80211_hw *hw = &local->hw;
 703         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 704         struct sta_info *sta = rx->sta;
 705         struct tid_ampdu_rx *tid_agg_rx;
 706         u16 sc;
 707         int tid;
 708
 709         if (!ieee80211_is_data_qos(hdr->frame_control))
 710                 goto dont_reorder;
 711
 712         /*
 713          * filter the QoS data rx stream according to
 714          * STA/TID and check if this STA/TID is on aggregation
 715          */
 716
 717         if (!sta)
 718                 goto dont_reorder;
 719
 720         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
 721
 722         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
 723         if (!tid_agg_rx)
 724                 goto dont_reorder;
 725
 726         /* qos null data frames are excluded */
 727         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
 728                 goto dont_reorder;
 729
 730         /* new, potentially un-ordered, ampdu frame - process it */
 731
 732         /* reset session timer */
 733         if (tid_agg_rx->timeout)
 734                 mod_timer(&tid_agg_rx->session_timer,
 735                           TU_TO_EXP_TIME(tid_agg_rx->timeout));
 736
 737         /* if this mpdu is fragmented - terminate rx aggregation session */
 738         sc = le16_to_cpu(hdr->seq_ctrl);
 739         if (sc & IEEE80211_SCTL_FRAG) {
 740                 skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
 741                 skb_queue_tail(&rx->sdata->skb_queue, skb);
 742                 ieee80211_queue_work(&local->hw, &rx->sdata->work);
 743                 return;
 744         }
 745
 746         /*
 747          * No locking needed -- we will only ever process one
 748          * RX packet at a time, and thus own tid_agg_rx. All
 749          * other code manipulating it needs to (and does) make
 750          * sure that we cannot get to it any more before doing
 751          * anything with it.
 752          */
 753         if (ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb, frames))
 754                 return;
 755
 756  dont_reorder:
 757         __skb_queue_tail(frames, skb);
 758 }
 759
 760 static ieee80211_rx_result debug_noinline
 761 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
 762 {
 763         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 764
 765         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 766         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 767                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
 768                              rx->sta->last_seq_ctrl[rx->queue] ==
 769                              hdr->seq_ctrl)) {
 770                         if (rx->flags & IEEE80211_RX_RA_MATCH) {
 771                                 rx->local->dot11FrameDuplicateCount++;
 772                                 rx->sta->num_duplicates++;
 773                         }
 774                         return RX_DROP_MONITOR;
 775                 } else
 776                         rx->sta->last_seq_ctrl[rx->queue] = hdr->seq_ctrl;
 777         }
 778
 779         if (unlikely(rx->skb->len < 16)) {
 780                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 781                 return RX_DROP_MONITOR;
 782         }
 783
 784         /* Drop disallowed frame classes based on STA auth/assoc state;
 785          * IEEE 802.11, Chap 5.5.
 786          *
 787          * mac80211 filters only based on association state, i.e. it drops
 788          * Class 3 frames from not associated stations. hostapd sends
 789          * deauth/disassoc frames when needed. In addition, hostapd is
 790          * responsible for filtering on both auth and assoc states.
 791          */
 792
 793         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
 794                 return ieee80211_rx_mesh_check(rx);
 795
 796         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
 797                       ieee80211_is_pspoll(hdr->frame_control)) &&
 798                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
 799                      (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC)))) {
 800                 if ((!ieee80211_has_fromds(hdr->frame_control) &&
 801                      !ieee80211_has_tods(hdr->frame_control) &&
 802                      ieee80211_is_data(hdr->frame_control)) ||
 803                     !(rx->flags & IEEE80211_RX_RA_MATCH)) {
 804                         /* Drop IBSS frames and frames for other hosts
 805                          * silently. */
 806                         return RX_DROP_MONITOR;
 807                 }
 808
 809                 return RX_DROP_MONITOR;
 810         }
 811
 812         return RX_CONTINUE;
 813 }
 814
 815
 816 static ieee80211_rx_result debug_noinline
 817 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
 818 {
 819         struct sk_buff *skb = rx->skb;
 820         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 821         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 822         int keyidx;
 823         int hdrlen;
 824         ieee80211_rx_result result = RX_DROP_UNUSABLE;
 825         struct ieee80211_key *stakey = NULL;
 826         int mmie_keyidx = -1;
 827         __le16 fc;
 828
 829         /*
 830          * Key selection 101
 831          *
 832          * There are four types of keys:
 833          *  - GTK (group keys)
 834          *  - IGTK (group keys for management frames)
 835          *  - PTK (pairwise keys)
 836          *  - STK (station-to-station pairwise keys)
 837          *
 838          * When selecting a key, we have to distinguish between multicast
 839          * (including broadcast) and unicast frames, the latter can only
 840          * use PTKs and STKs while the former always use GTKs and IGTKs.
 841          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
 842          * unicast frames can also use key indices like GTKs. Hence, if we
 843          * don't have a PTK/STK we check the key index for a WEP key.
 844          *
 845          * Note that in a regular BSS, multicast frames are sent by the
 846          * AP only, associated stations unicast the frame to the AP first
 847          * which then multicasts it on their behalf.
 848          *
 849          * There is also a slight problem in IBSS mode: GTKs are negotiated
 850          * with each station, that is something we don't currently handle.
 851          * The spec seems to expect that one negotiates the same key with
 852          * every station but there's no such requirement; VLANs could be
 853          * possible.
 854          */
 855
 856         /*
 857          * No point in finding a key and decrypting if the frame is neither
 858          * addressed to us nor a multicast frame.
 859          */
 860         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
 861                 return RX_CONTINUE;
 862
 863         /* start without a key */
 864         rx->key = NULL;
 865
 866         if (rx->sta)
 867                 stakey = rcu_dereference(rx->sta->key);
 868
 869         fc = hdr->frame_control;
 870
 871         if (!ieee80211_has_protected(fc))
 872                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
 873
 874         if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
 875                 rx->key = stakey;
 876                 /* Skip decryption if the frame is not protected. */
 877                 if (!ieee80211_has_protected(fc))
 878                         return RX_CONTINUE;
 879         } else if (mmie_keyidx >= 0) {
 880                 /* Broadcast/multicast robust management frame / BIP */
 881                 if ((status->flag & RX_FLAG_DECRYPTED) &&
 882                     (status->flag & RX_FLAG_IV_STRIPPED))
 883                         return RX_CONTINUE;
 884
 885                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
 886                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
 887                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
 888                 rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
 889         } else if (!ieee80211_has_protected(fc)) {
 890                 /*
 891                  * The frame was not protected, so skip decryption. However, we
 892                  * need to set rx->key if there is a key that could have been
 893                  * used so that the frame may be dropped if encryption would
 894                  * have been expected.
 895                  */
 896                 struct ieee80211_key *key = NULL;
 897                 if (ieee80211_is_mgmt(fc) &&
 898                     is_multicast_ether_addr(hdr->addr1) &&
 899                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
 900                         rx->key = key;
 901                 else if ((key = rcu_dereference(rx->sdata->default_key)))
 902                         rx->key = key;
 903                 return RX_CONTINUE;
 904         } else {
 905                 u8 keyid;
 906                 /*
 907                  * The device doesn't give us the IV so we won't be
 908                  * able to look up the key. That's ok though, we
 909                  * don't need to decrypt the frame, we just won't
 910                  * be able to keep statistics accurate.
 911                  * Except for key threshold notifications, should
 912                  * we somehow allow the driver to tell us which key
 913                  * the hardware used if this flag is set?
 914                  */
 915                 if ((status->flag & RX_FLAG_DECRYPTED) &&
 916                     (status->flag & RX_FLAG_IV_STRIPPED))
 917                         return RX_CONTINUE;
 918
 919                 hdrlen = ieee80211_hdrlen(fc);
 920
 921                 if (rx->skb->len < 8 + hdrlen)
 922                         return RX_DROP_UNUSABLE; /* TODO: count this? */
 923
 924                 /*
 925                  * no need to call ieee80211_wep_get_keyidx,
 926                  * it verifies a bunch of things we've done already
 927                  */
 928                 skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
 929                 keyidx = keyid >> 6;
 930
 931                 rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
 932
 933                 /*
 934                  * RSNA-protected unicast frames should always be sent with
 935                  * pairwise or station-to-station keys, but for WEP we allow
 936                  * using a key index as well.
 937                  */
 938                 if (rx->key && rx->key->conf.alg != ALG_WEP &&
 939                     !is_multicast_ether_addr(hdr->addr1))
 940                         rx->key = NULL;
 941         }
 942
 943         if (rx->key) {
 944                 rx->key->tx_rx_count++;
 945                 /* TODO: add threshold stuff again */
 946         } else {
 947                 return RX_DROP_MONITOR;
 948         }
 949
 950         if (skb_linearize(rx->skb))
 951                 return RX_DROP_UNUSABLE;
 952         /* the hdr variable is invalid now! */
 953
 954         switch (rx->key->conf.alg) {
 955         case ALG_WEP:
 956                 /* Check for weak IVs if possible */
 957                 if (rx->sta && ieee80211_is_data(fc) &&
 958                     (!(status->flag & RX_FLAG_IV_STRIPPED) ||
 959                      !(status->flag & RX_FLAG_DECRYPTED)) &&
 960                     ieee80211_wep_is_weak_iv(rx->skb, rx->key))
 961                         rx->sta->wep_weak_iv_count++;
 962
 963                 result = ieee80211_crypto_wep_decrypt(rx);
 964                 break;
 965         case ALG_TKIP:
 966                 result = ieee80211_crypto_tkip_decrypt(rx);
 967                 break;
 968         case ALG_CCMP:
 969                 result = ieee80211_crypto_ccmp_decrypt(rx);
 970                 break;
 971         case ALG_AES_CMAC:
 972                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
 973                 break;
 974         }
 975
 976         /* either the frame has been decrypted or will be dropped */
 977         status->flag |= RX_FLAG_DECRYPTED;
 978
 979         return result;
 980 }
 981
 982 static ieee80211_rx_result debug_noinline
 983 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
 984 {
 985         struct ieee80211_local *local;
 986         struct ieee80211_hdr *hdr;
 987         struct sk_buff *skb;
 988
 989         local = rx->local;
 990         skb = rx->skb;
 991         hdr = (struct ieee80211_hdr *) skb->data;
 992
 993         if (!local->pspolling)
 994                 return RX_CONTINUE;
 995
 996         if (!ieee80211_has_fromds(hdr->frame_control))
 997                 /* this is not from AP */
 998                 return RX_CONTINUE;
 999
1000         if (!ieee80211_is_data(hdr->frame_control))
1001                 return RX_CONTINUE;
1002
1003         if (!ieee80211_has_moredata(hdr->frame_control)) {
1004                 /* AP has no more frames buffered for us */
1005                 local->pspolling = false;
1006                 return RX_CONTINUE;
1007         }
1008
1009         /* more data bit is set, let's request a new frame from the AP */
1010         ieee80211_send_pspoll(local, rx->sdata);
1011
1012         return RX_CONTINUE;
1013 }
1014
1015 static void ap_sta_ps_start(struct sta_info *sta)
1016 {
1017         struct ieee80211_sub_if_data *sdata = sta->sdata;
1018         struct ieee80211_local *local = sdata->local;
1019
1020         atomic_inc(&sdata->bss->num_sta_ps);
1021         set_sta_flags(sta, WLAN_STA_PS_STA);
1022         drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1023 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1024         printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
1025                sdata->name, sta->sta.addr, sta->sta.aid);
1026 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1027 }
1028
1029 static void ap_sta_ps_end(struct sta_info *sta)
1030 {
1031         struct ieee80211_sub_if_data *sdata = sta->sdata;
1032
1033         atomic_dec(&sdata->bss->num_sta_ps);
1034
1035         clear_sta_flags(sta, WLAN_STA_PS_STA);
1036
1037 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1038         printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
1039                sdata->name, sta->sta.addr, sta->sta.aid);
1040 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1041
1042         if (test_sta_flags(sta, WLAN_STA_PS_DRIVER)) {
1043 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1044                 printk(KERN_DEBUG "%s: STA %pM aid %d driver-ps-blocked\n",
1045                        sdata->name, sta->sta.addr, sta->sta.aid);
1046 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1047                 return;
1048         }
1049
1050         ieee80211_sta_ps_deliver_wakeup(sta);
1051 }
1052
1053 static ieee80211_rx_result debug_noinline
1054 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1055 {
1056         struct sta_info *sta = rx->sta;
1057         struct sk_buff *skb = rx->skb;
1058         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1059         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1060
1061         if (!sta)
1062                 return RX_CONTINUE;
1063
1064         /*
1065          * Update last_rx only for IBSS packets which are for the current
1066          * BSSID to avoid keeping the current IBSS network alive in cases
1067          * where other STAs start using different BSSID.
1068          */
1069         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1070                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1071                                                 NL80211_IFTYPE_ADHOC);
1072                 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0)
1073                         sta->last_rx = jiffies;
1074         } else if (!is_multicast_ether_addr(hdr->addr1)) {
1075                 /*
1076                  * Mesh beacons will update last_rx when if they are found to
1077                  * match the current local configuration when processed.
1078                  */
1079                 sta->last_rx = jiffies;
1080         }
1081
1082         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1083                 return RX_CONTINUE;
1084
1085         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1086                 ieee80211_sta_rx_notify(rx->sdata, hdr);
1087
1088         sta->rx_fragments++;
1089         sta->rx_bytes += rx->skb->len;
1090         sta->last_signal = status->signal;
1091
1092         /*
1093          * Change STA power saving mode only at the end of a frame
1094          * exchange sequence.
1095          */
1096         if (!ieee80211_has_morefrags(hdr->frame_control) &&
1097             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1098              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1099                 if (test_sta_flags(sta, WLAN_STA_PS_STA)) {
1100                         /*
1101                          * Ignore doze->wake transitions that are
1102                          * indicated by non-data frames, the standard
1103                          * is unclear here, but for example going to
1104                          * PS mode and then scanning would cause a
1105                          * doze->wake transition for the probe request,
1106                          * and that is clearly undesirable.
1107                          */
1108                         if (ieee80211_is_data(hdr->frame_control) &&
1109                             !ieee80211_has_pm(hdr->frame_control))
1110                                 ap_sta_ps_end(sta);
1111                 } else {
1112                         if (ieee80211_has_pm(hdr->frame_control))
1113                                 ap_sta_ps_start(sta);
1114                 }
1115         }
1116
1117         /*
1118          * Drop (qos-)data::nullfunc frames silently, since they
1119          * are used only to control station power saving mode.
1120          */
1121         if (ieee80211_is_nullfunc(hdr->frame_control) ||
1122             ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1123                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1124
1125                 /*
1126                  * If we receive a 4-addr nullfunc frame from a STA
1127                  * that was not moved to a 4-addr STA vlan yet, drop
1128                  * the frame to the monitor interface, to make sure
1129                  * that hostapd sees it
1130                  */
1131                 if (ieee80211_has_a4(hdr->frame_control) &&
1132                     (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1133                      (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1134                       !rx->sdata->u.vlan.sta)))
1135                         return RX_DROP_MONITOR;
1136                 /*
1137                  * Update counter and free packet here to avoid
1138                  * counting this as a dropped packed.
1139                  */
1140                 sta->rx_packets++;
1141                 dev_kfree_skb(rx->skb);
1142                 return RX_QUEUED;
1143         }
1144
1145         return RX_CONTINUE;
1146 } /* ieee80211_rx_h_sta_process */
1147
1148 static inline struct ieee80211_fragment_entry *
1149 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1150                          unsigned int frag, unsigned int seq, int rx_queue,
1151                          struct sk_buff **skb)
1152 {
1153         struct ieee80211_fragment_entry *entry;
1154         int idx;
1155
1156         idx = sdata->fragment_next;
1157         entry = &sdata->fragments[sdata->fragment_next++];
1158         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1159                 sdata->fragment_next = 0;
1160
1161         if (!skb_queue_empty(&entry->skb_list)) {
1162 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1163                 struct ieee80211_hdr *hdr =
1164                         (struct ieee80211_hdr *) entry->skb_list.next->data;
1165                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
1166                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
1167                        "addr1=%pM addr2=%pM\n",
1168                        sdata->name, idx,
1169                        jiffies - entry->first_frag_time, entry->seq,
1170                        entry->last_frag, hdr->addr1, hdr->addr2);
1171 #endif
1172                 __skb_queue_purge(&entry->skb_list);
1173         }
1174
1175         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1176         *skb = NULL;
1177         entry->first_frag_time = jiffies;
1178         entry->seq = seq;
1179         entry->rx_queue = rx_queue;
1180         entry->last_frag = frag;
1181         entry->ccmp = 0;
1182         entry->extra_len = 0;
1183
1184         return entry;
1185 }
1186
1187 static inline struct ieee80211_fragment_entry *
1188 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1189                           unsigned int frag, unsigned int seq,
1190                           int rx_queue, struct ieee80211_hdr *hdr)
1191 {
1192         struct ieee80211_fragment_entry *entry;
1193         int i, idx;
1194
1195         idx = sdata->fragment_next;
1196         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1197                 struct ieee80211_hdr *f_hdr;
1198
1199                 idx--;
1200                 if (idx < 0)
1201                         idx = IEEE80211_FRAGMENT_MAX - 1;
1202
1203                 entry = &sdata->fragments[idx];
1204                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1205                     entry->rx_queue != rx_queue ||
1206                     entry->last_frag + 1 != frag)
1207                         continue;
1208
1209                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1210
1211                 /*
1212                  * Check ftype and addresses are equal, else check next fragment
1213                  */
1214                 if (((hdr->frame_control ^ f_hdr->frame_control) &
1215                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1216                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
1217                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
1218                         continue;
1219
1220                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1221                         __skb_queue_purge(&entry->skb_list);
1222                         continue;
1223                 }
1224                 return entry;
1225         }
1226
1227         return NULL;
1228 }
1229
1230 static ieee80211_rx_result debug_noinline
1231 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1232 {
1233         struct ieee80211_hdr *hdr;
1234         u16 sc;
1235         __le16 fc;
1236         unsigned int frag, seq;
1237         struct ieee80211_fragment_entry *entry;
1238         struct sk_buff *skb;
1239
1240         hdr = (struct ieee80211_hdr *)rx->skb->data;
1241         fc = hdr->frame_control;
1242         sc = le16_to_cpu(hdr->seq_ctrl);
1243         frag = sc & IEEE80211_SCTL_FRAG;
1244
1245         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1246                    (rx->skb)->len < 24 ||
1247                    is_multicast_ether_addr(hdr->addr1))) {
1248                 /* not fragmented */
1249                 goto out;
1250         }
1251         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1252
1253         if (skb_linearize(rx->skb))
1254                 return RX_DROP_UNUSABLE;
1255
1256         /*
1257          *  skb_linearize() might change the skb->data and
1258          *  previously cached variables (in this case, hdr) need to
1259          *  be refreshed with the new data.
1260          */
1261         hdr = (struct ieee80211_hdr *)rx->skb->data;
1262         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1263
1264         if (frag == 0) {
1265                 /* This is the first fragment of a new frame. */
1266                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1267                                                  rx->queue, &(rx->skb));
1268                 if (rx->key && rx->key->conf.alg == ALG_CCMP &&
1269                     ieee80211_has_protected(fc)) {
1270                         /* Store CCMP PN so that we can verify that the next
1271                          * fragment has a sequential PN value. */
1272                         entry->ccmp = 1;
1273                         memcpy(entry->last_pn,
1274                                rx->key->u.ccmp.rx_pn[rx->queue],
1275                                CCMP_PN_LEN);
1276                 }
1277                 return RX_QUEUED;
1278         }
1279
1280         /* This is a fragment for a frame that should already be pending in
1281          * fragment cache. Add this fragment to the end of the pending entry.
1282          */
1283         entry = ieee80211_reassemble_find(rx->sdata, frag, seq, rx->queue, hdr);
1284         if (!entry) {
1285                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1286                 return RX_DROP_MONITOR;
1287         }
1288
1289         /* Verify that MPDUs within one MSDU have sequential PN values.
1290          * (IEEE 802.11i, 8.3.3.4.5) */
1291         if (entry->ccmp) {
1292                 int i;
1293                 u8 pn[CCMP_PN_LEN], *rpn;
1294                 if (!rx->key || rx->key->conf.alg != ALG_CCMP)
1295                         return RX_DROP_UNUSABLE;
1296                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1297                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1298                         pn[i]++;
1299                         if (pn[i])
1300                                 break;
1301                 }
1302                 rpn = rx->key->u.ccmp.rx_pn[rx->queue];
1303                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1304                         return RX_DROP_UNUSABLE;
1305                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1306         }
1307
1308         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1309         __skb_queue_tail(&entry->skb_list, rx->skb);
1310         entry->last_frag = frag;
1311         entry->extra_len += rx->skb->len;
1312         if (ieee80211_has_morefrags(fc)) {
1313                 rx->skb = NULL;
1314                 return RX_QUEUED;
1315         }
1316
1317         rx->skb = __skb_dequeue(&entry->skb_list);
1318         if (skb_tailroom(rx->skb) < entry->extra_len) {
1319                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1320                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1321                                               GFP_ATOMIC))) {
1322                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1323                         __skb_queue_purge(&entry->skb_list);
1324                         return RX_DROP_UNUSABLE;
1325                 }
1326         }
1327         while ((skb = __skb_dequeue(&entry->skb_list))) {
1328                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1329                 dev_kfree_skb(skb);
1330         }
1331
1332         /* Complete frame has been reassembled - process it now */
1333         rx->flags |= IEEE80211_RX_FRAGMENTED;
1334
1335  out:
1336         if (rx->sta)
1337                 rx->sta->rx_packets++;
1338         if (is_multicast_ether_addr(hdr->addr1))
1339                 rx->local->dot11MulticastReceivedFrameCount++;
1340         else
1341                 ieee80211_led_rx(rx->local);
1342         return RX_CONTINUE;
1343 }
1344
1345 static ieee80211_rx_result debug_noinline
1346 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
1347 {
1348         struct ieee80211_sub_if_data *sdata = rx->sdata;
1349         __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
1350
1351         if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
1352                    !(rx->flags & IEEE80211_RX_RA_MATCH)))
1353                 return RX_CONTINUE;
1354
1355         if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1356             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1357                 return RX_DROP_UNUSABLE;
1358
1359         if (!test_sta_flags(rx->sta, WLAN_STA_PS_DRIVER))
1360                 ieee80211_sta_ps_deliver_poll_response(rx->sta);
1361         else
1362                 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1363
1364         /* Free PS Poll skb here instead of returning RX_DROP that would
1365          * count as an dropped frame. */
1366         dev_kfree_skb(rx->skb);
1367
1368         return RX_QUEUED;
1369 }
1370
1371 static ieee80211_rx_result debug_noinline
1372 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1373 {
1374         u8 *data = rx->skb->data;
1375         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1376
1377         if (!ieee80211_is_data_qos(hdr->frame_control))
1378                 return RX_CONTINUE;
1379
1380         /* remove the qos control field, update frame type and meta-data */
1381         memmove(data + IEEE80211_QOS_CTL_LEN, data,
1382                 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1383         hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1384         /* change frame type to non QOS */
1385         hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1386
1387         return RX_CONTINUE;
1388 }
1389
1390 static int
1391 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1392 {
1393         if (unlikely(!rx->sta ||
1394             !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1395                 return -EACCES;
1396
1397         return 0;
1398 }
1399
1400 static int
1401 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1402 {
1403         struct sk_buff *skb = rx->skb;
1404         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1405
1406         /*
1407          * Pass through unencrypted frames if the hardware has
1408          * decrypted them already.
1409          */
1410         if (status->flag & RX_FLAG_DECRYPTED)
1411                 return 0;
1412
1413         /* Drop unencrypted frames if key is set. */
1414         if (unlikely(!ieee80211_has_protected(fc) &&
1415                      !ieee80211_is_nullfunc(fc) &&
1416                      ieee80211_is_data(fc) &&
1417                      (rx->key || rx->sdata->drop_unencrypted)))
1418                 return -EACCES;
1419
1420         return 0;
1421 }
1422
1423 static int
1424 ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1425 {
1426         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1427         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1428         __le16 fc = hdr->frame_control;
1429
1430         /*
1431          * Pass through unencrypted frames if the hardware has
1432          * decrypted them already.
1433          */
1434         if (status->flag & RX_FLAG_DECRYPTED)
1435                 return 0;
1436
1437         if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) {
1438                 if (unlikely(!ieee80211_has_protected(fc) &&
1439                              ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1440                              rx->key))
1441                         return -EACCES;
1442                 /* BIP does not use Protected field, so need to check MMIE */
1443                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1444                              ieee80211_get_mmie_keyidx(rx->skb) < 0))
1445                         return -EACCES;
1446                 /*
1447                  * When using MFP, Action frames are not allowed prior to
1448                  * having configured keys.
1449                  */
1450                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1451                              ieee80211_is_robust_mgmt_frame(
1452                                      (struct ieee80211_hdr *) rx->skb->data)))
1453                         return -EACCES;
1454         }
1455
1456         return 0;
1457 }
1458
1459 static int
1460 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx)
1461 {
1462         struct ieee80211_sub_if_data *sdata = rx->sdata;
1463         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1464
1465         if (ieee80211_has_a4(hdr->frame_control) &&
1466             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1467                 return -1;
1468
1469         if (is_multicast_ether_addr(hdr->addr1) &&
1470             ((sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta) ||
1471              (sdata->vif.type == NL80211_IFTYPE_STATION && sdata->u.mgd.use_4addr)))
1472                 return -1;
1473
1474         return ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1475 }
1476
1477 /*
1478  * requires that rx->skb is a frame with ethernet header
1479  */
1480 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1481 {
1482         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1483                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1484         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1485
1486         /*
1487          * Allow EAPOL frames to us/the PAE group address regardless
1488          * of whether the frame was encrypted or not.
1489          */
1490         if (ehdr->h_proto == htons(ETH_P_PAE) &&
1491             (compare_ether_addr(ehdr->h_dest, rx->sdata->vif.addr) == 0 ||
1492              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1493                 return true;
1494
1495         if (ieee80211_802_1x_port_control(rx) ||
1496             ieee80211_drop_unencrypted(rx, fc))
1497                 return false;
1498
1499         return true;
1500 }
1501
1502 /*
1503  * requires that rx->skb is a frame with ethernet header
1504  */
1505 static void
1506 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1507 {
1508         struct ieee80211_sub_if_data *sdata = rx->sdata;
1509         struct net_device *dev = sdata->dev;
1510         struct sk_buff *skb, *xmit_skb;
1511         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1512         struct sta_info *dsta;
1513
1514         skb = rx->skb;
1515         xmit_skb = NULL;
1516
1517         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1518              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1519             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1520             (rx->flags & IEEE80211_RX_RA_MATCH) &&
1521             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1522                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1523                         /*
1524                          * send multicast frames both to higher layers in
1525                          * local net stack and back to the wireless medium
1526                          */
1527                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1528                         if (!xmit_skb && net_ratelimit())
1529                                 printk(KERN_DEBUG "%s: failed to clone "
1530                                        "multicast frame\n", dev->name);
1531                 } else {
1532                         dsta = sta_info_get(sdata, skb->data);
1533                         if (dsta) {
1534                                 /*
1535                                  * The destination station is associated to
1536                                  * this AP (in this VLAN), so send the frame
1537                                  * directly to it and do not pass it to local
1538                                  * net stack.
1539                                  */
1540                                 xmit_skb = skb;
1541                                 skb = NULL;
1542                         }
1543                 }
1544         }
1545
1546         if (skb) {
1547                 int align __maybe_unused;
1548
1549 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1550                 /*
1551                  * 'align' will only take the values 0 or 2 here
1552                  * since all frames are required to be aligned
1553                  * to 2-byte boundaries when being passed to
1554                  * mac80211. That also explains the __skb_push()
1555                  * below.
1556                  */
1557                 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1558                 if (align) {
1559                         if (WARN_ON(skb_headroom(skb) < 3)) {
1560                                 dev_kfree_skb(skb);
1561                                 skb = NULL;
1562                         } else {
1563                                 u8 *data = skb->data;
1564                                 size_t len = skb_headlen(skb);
1565                                 skb->data -= align;
1566                                 memmove(skb->data, data, len);
1567                                 skb_set_tail_pointer(skb, len);
1568                         }
1569                 }
1570 #endif
1571
1572                 if (skb) {
1573                         /* deliver to local stack */
1574                         skb->protocol = eth_type_trans(skb, dev);
1575                         memset(skb->cb, 0, sizeof(skb->cb));
1576                         netif_rx(skb);
1577                 }
1578         }
1579
1580         if (xmit_skb) {
1581                 /* send to wireless media */
1582                 xmit_skb->protocol = htons(ETH_P_802_3);
1583                 skb_reset_network_header(xmit_skb);
1584                 skb_reset_mac_header(xmit_skb);
1585                 dev_queue_xmit(xmit_skb);
1586         }
1587 }
1588
1589 static ieee80211_rx_result debug_noinline
1590 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1591 {
1592         struct net_device *dev = rx->sdata->dev;
1593         struct sk_buff *skb = rx->skb;
1594         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1595         __le16 fc = hdr->frame_control;
1596         struct sk_buff_head frame_list;
1597
1598         if (unlikely(!ieee80211_is_data(fc)))
1599                 return RX_CONTINUE;
1600
1601         if (unlikely(!ieee80211_is_data_present(fc)))
1602                 return RX_DROP_MONITOR;
1603
1604         if (!(rx->flags & IEEE80211_RX_AMSDU))
1605                 return RX_CONTINUE;
1606
1607         if (ieee80211_has_a4(hdr->frame_control) &&
1608             rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1609             !rx->sdata->u.vlan.sta)
1610                 return RX_DROP_UNUSABLE;
1611
1612         if (is_multicast_ether_addr(hdr->addr1) &&
1613             ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1614               rx->sdata->u.vlan.sta) ||
1615              (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1616               rx->sdata->u.mgd.use_4addr)))
1617                 return RX_DROP_UNUSABLE;
1618
1619         skb->dev = dev;
1620         __skb_queue_head_init(&frame_list);
1621
1622         if (skb_linearize(skb))
1623                 return RX_DROP_UNUSABLE;
1624
1625         ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1626                                  rx->sdata->vif.type,
1627                                  rx->local->hw.extra_tx_headroom);
1628
1629         while (!skb_queue_empty(&frame_list)) {
1630                 rx->skb = __skb_dequeue(&frame_list);
1631
1632                 if (!ieee80211_frame_allowed(rx, fc)) {
1633                         dev_kfree_skb(rx->skb);
1634                         continue;
1635                 }
1636                 dev->stats.rx_packets++;
1637                 dev->stats.rx_bytes += rx->skb->len;
1638
1639                 ieee80211_deliver_skb(rx);
1640         }
1641
1642         return RX_QUEUED;
1643 }
1644
1645 #ifdef CONFIG_MAC80211_MESH
1646 static ieee80211_rx_result
1647 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1648 {
1649         struct ieee80211_hdr *hdr;
1650         struct ieee80211s_hdr *mesh_hdr;
1651         unsigned int hdrlen;
1652         struct sk_buff *skb = rx->skb, *fwd_skb;
1653         struct ieee80211_local *local = rx->local;
1654         struct ieee80211_sub_if_data *sdata = rx->sdata;
1655
1656         hdr = (struct ieee80211_hdr *) skb->data;
1657         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1658         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1659
1660         if (!ieee80211_is_data(hdr->frame_control))
1661                 return RX_CONTINUE;
1662
1663         if (!mesh_hdr->ttl)
1664                 /* illegal frame */
1665                 return RX_DROP_MONITOR;
1666
1667         if (mesh_hdr->flags & MESH_FLAGS_AE) {
1668                 struct mesh_path *mppath;
1669                 char *proxied_addr;
1670                 char *mpp_addr;
1671
1672                 if (is_multicast_ether_addr(hdr->addr1)) {
1673                         mpp_addr = hdr->addr3;
1674                         proxied_addr = mesh_hdr->eaddr1;
1675                 } else {
1676                         mpp_addr = hdr->addr4;
1677                         proxied_addr = mesh_hdr->eaddr2;
1678                 }
1679
1680                 rcu_read_lock();
1681                 mppath = mpp_path_lookup(proxied_addr, sdata);
1682                 if (!mppath) {
1683                         mpp_path_add(proxied_addr, mpp_addr, sdata);
1684                 } else {
1685                         spin_lock_bh(&mppath->state_lock);
1686                         if (compare_ether_addr(mppath->mpp, mpp_addr) != 0)
1687                                 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
1688                         spin_unlock_bh(&mppath->state_lock);
1689                 }
1690                 rcu_read_unlock();
1691         }
1692
1693         /* Frame has reached destination.  Don't forward */
1694         if (!is_multicast_ether_addr(hdr->addr1) &&
1695             compare_ether_addr(sdata->vif.addr, hdr->addr3) == 0)
1696                 return RX_CONTINUE;
1697
1698         mesh_hdr->ttl--;
1699
1700         if (rx->flags & IEEE80211_RX_RA_MATCH) {
1701                 if (!mesh_hdr->ttl)
1702                         IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1703                                                      dropped_frames_ttl);
1704                 else {
1705                         struct ieee80211_hdr *fwd_hdr;
1706                         struct ieee80211_tx_info *info;
1707
1708                         fwd_skb = skb_copy(skb, GFP_ATOMIC);
1709
1710                         if (!fwd_skb && net_ratelimit())
1711                                 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1712                                                    sdata->name);
1713
1714                         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1715                         memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
1716                         info = IEEE80211_SKB_CB(fwd_skb);
1717                         memset(info, 0, sizeof(*info));
1718                         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1719                         info->control.vif = &rx->sdata->vif;
1720                         skb_set_queue_mapping(skb,
1721                                 ieee80211_select_queue(rx->sdata, fwd_skb));
1722                         ieee80211_set_qos_hdr(local, skb);
1723                         if (is_multicast_ether_addr(fwd_hdr->addr1))
1724                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1725                                                                 fwded_mcast);
1726                         else {
1727                                 int err;
1728                                 /*
1729                                  * Save TA to addr1 to send TA a path error if a
1730                                  * suitable next hop is not found
1731                                  */
1732                                 memcpy(fwd_hdr->addr1, fwd_hdr->addr2,
1733                                                 ETH_ALEN);
1734                                 err = mesh_nexthop_lookup(fwd_skb, sdata);
1735                                 /* Failed to immediately resolve next hop:
1736                                  * fwded frame was dropped or will be added
1737                                  * later to the pending skb queue.  */
1738                                 if (err)
1739                                         return RX_DROP_MONITOR;
1740
1741                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1742                                                                 fwded_unicast);
1743                         }
1744                         IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1745                                                      fwded_frames);
1746                         ieee80211_add_pending_skb(local, fwd_skb);
1747                 }
1748         }
1749
1750         if (is_multicast_ether_addr(hdr->addr1) ||
1751             sdata->dev->flags & IFF_PROMISC)
1752                 return RX_CONTINUE;
1753         else
1754                 return RX_DROP_MONITOR;
1755 }
1756 #endif
1757
1758 static ieee80211_rx_result debug_noinline
1759 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1760 {
1761         struct ieee80211_sub_if_data *sdata = rx->sdata;
1762         struct ieee80211_local *local = rx->local;
1763         struct net_device *dev = sdata->dev;
1764         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1765         __le16 fc = hdr->frame_control;
1766         int err;
1767
1768         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1769                 return RX_CONTINUE;
1770
1771         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1772                 return RX_DROP_MONITOR;
1773
1774         /*
1775          * Allow the cooked monitor interface of an AP to see 4-addr frames so
1776          * that a 4-addr station can be detected and moved into a separate VLAN
1777          */
1778         if (ieee80211_has_a4(hdr->frame_control) &&
1779             sdata->vif.type == NL80211_IFTYPE_AP)
1780                 return RX_DROP_MONITOR;
1781
1782         err = __ieee80211_data_to_8023(rx);
1783         if (unlikely(err))
1784                 return RX_DROP_UNUSABLE;
1785
1786         if (!ieee80211_frame_allowed(rx, fc))
1787                 return RX_DROP_MONITOR;
1788
1789         rx->skb->dev = dev;
1790
1791         dev->stats.rx_packets++;
1792         dev->stats.rx_bytes += rx->skb->len;
1793
1794         if (ieee80211_is_data(hdr->frame_control) &&
1795             !is_multicast_ether_addr(hdr->addr1) &&
1796             local->hw.conf.dynamic_ps_timeout > 0 && local->ps_sdata) {
1797                         mod_timer(&local->dynamic_ps_timer, jiffies +
1798                          msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
1799         }
1800
1801         ieee80211_deliver_skb(rx);
1802
1803         return RX_QUEUED;
1804 }
1805
1806 static ieee80211_rx_result debug_noinline
1807 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
1808 {
1809         struct ieee80211_local *local = rx->local;
1810         struct ieee80211_hw *hw = &local->hw;
1811         struct sk_buff *skb = rx->skb;
1812         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1813         struct tid_ampdu_rx *tid_agg_rx;
1814         u16 start_seq_num;
1815         u16 tid;
1816
1817         if (likely(!ieee80211_is_ctl(bar->frame_control)))
1818                 return RX_CONTINUE;
1819
1820         if (ieee80211_is_back_req(bar->frame_control)) {
1821                 struct {
1822                         __le16 control, start_seq_num;
1823                 } __packed bar_data;
1824
1825                 if (!rx->sta)
1826                         return RX_DROP_MONITOR;
1827
1828                 if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
1829                                   &bar_data, sizeof(bar_data)))
1830                         return RX_DROP_MONITOR;
1831
1832                 tid = le16_to_cpu(bar_data.control) >> 12;
1833
1834                 tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
1835                 if (!tid_agg_rx)
1836                         return RX_DROP_MONITOR;
1837
1838                 start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
1839
1840                 /* reset session timer */
1841                 if (tid_agg_rx->timeout)
1842                         mod_timer(&tid_agg_rx->session_timer,
1843                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
1844
1845                 /* release stored frames up to start of BAR */
1846                 ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num,
1847                                                  frames);
1848                 kfree_skb(skb);
1849                 return RX_QUEUED;
1850         }
1851
1852         /*
1853          * After this point, we only want management frames,
1854          * so we can drop all remaining control frames to
1855          * cooked monitor interfaces.
1856          */
1857         return RX_DROP_MONITOR;
1858 }
1859
1860 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
1861                                            struct ieee80211_mgmt *mgmt,
1862                                            size_t len)
1863 {
1864         struct ieee80211_local *local = sdata->local;
1865         struct sk_buff *skb;
1866         struct ieee80211_mgmt *resp;
1867
1868         if (compare_ether_addr(mgmt->da, sdata->vif.addr) != 0) {
1869                 /* Not to own unicast address */
1870                 return;
1871         }
1872
1873         if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
1874             compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
1875                 /* Not from the current AP or not associated yet. */
1876                 return;
1877         }
1878
1879         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
1880                 /* Too short SA Query request frame */
1881                 return;
1882         }
1883
1884         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
1885         if (skb == NULL)
1886                 return;
1887
1888         skb_reserve(skb, local->hw.extra_tx_headroom);
1889         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
1890         memset(resp, 0, 24);
1891         memcpy(resp->da, mgmt->sa, ETH_ALEN);
1892         memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
1893         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
1894         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
1895                                           IEEE80211_STYPE_ACTION);
1896         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
1897         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
1898         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
1899         memcpy(resp->u.action.u.sa_query.trans_id,
1900                mgmt->u.action.u.sa_query.trans_id,
1901                WLAN_SA_QUERY_TR_ID_LEN);
1902
1903         ieee80211_tx_skb(sdata, skb);
1904 }
1905
1906 static ieee80211_rx_result debug_noinline
1907 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
1908 {
1909         struct ieee80211_local *local = rx->local;
1910         struct ieee80211_sub_if_data *sdata = rx->sdata;
1911         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
1912         struct sk_buff *nskb;
1913         struct ieee80211_rx_status *status;
1914         int len = rx->skb->len;
1915
1916         if (!ieee80211_is_action(mgmt->frame_control))
1917                 return RX_CONTINUE;
1918
1919         /* drop too small frames */
1920         if (len < IEEE80211_MIN_ACTION_SIZE)
1921                 return RX_DROP_UNUSABLE;
1922
1923         if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC)
1924                 return RX_DROP_UNUSABLE;
1925
1926         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
1927                 return RX_DROP_UNUSABLE;
1928
1929         if (ieee80211_drop_unencrypted_mgmt(rx))
1930                 return RX_DROP_UNUSABLE;
1931
1932         switch (mgmt->u.action.category) {
1933         case WLAN_CATEGORY_BACK:
1934                 /*
1935                  * The aggregation code is not prepared to handle
1936                  * anything but STA/AP due to the BSSID handling;
1937                  * IBSS could work in the code but isn't supported
1938                  * by drivers or the standard.
1939                  */
1940                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
1941                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
1942                     sdata->vif.type != NL80211_IFTYPE_AP)
1943                         break;
1944
1945                 /* verify action_code is present */
1946                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
1947                         break;
1948
1949                 switch (mgmt->u.action.u.addba_req.action_code) {
1950                 case WLAN_ACTION_ADDBA_REQ:
1951                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1952                                    sizeof(mgmt->u.action.u.addba_req)))
1953                                 goto invalid;
1954                         break;
1955                 case WLAN_ACTION_ADDBA_RESP:
1956                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1957                                    sizeof(mgmt->u.action.u.addba_resp)))
1958                                 goto invalid;
1959                         break;
1960                 case WLAN_ACTION_DELBA:
1961                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1962                                    sizeof(mgmt->u.action.u.delba)))
1963                                 goto invalid;
1964                         break;
1965                 default:
1966                         goto invalid;
1967                 }
1968
1969                 rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
1970                 skb_queue_tail(&sdata->skb_queue, rx->skb);
1971                 ieee80211_queue_work(&local->hw, &sdata->work);
1972                 return RX_QUEUED;
1973         case WLAN_CATEGORY_SPECTRUM_MGMT:
1974                 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
1975                         break;
1976
1977                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
1978                         break;
1979
1980                 /* verify action_code is present */
1981                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
1982                         break;
1983
1984                 switch (mgmt->u.action.u.measurement.action_code) {
1985                 case WLAN_ACTION_SPCT_MSR_REQ:
1986                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1987                                    sizeof(mgmt->u.action.u.measurement)))
1988                                 break;
1989                         ieee80211_process_measurement_req(sdata, mgmt, len);
1990                         goto handled;
1991                 case WLAN_ACTION_SPCT_CHL_SWITCH:
1992                         if (len < (IEEE80211_MIN_ACTION_SIZE +
1993                                    sizeof(mgmt->u.action.u.chan_switch)))
1994                                 break;
1995
1996                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
1997                                 break;
1998
1999                         if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
2000                                 break;
2001
2002                         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2003                         skb_queue_tail(&sdata->skb_queue, rx->skb);
2004                         ieee80211_queue_work(&local->hw, &sdata->work);
2005                         return RX_QUEUED;
2006                 }
2007                 break;
2008         case WLAN_CATEGORY_SA_QUERY:
2009                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2010                            sizeof(mgmt->u.action.u.sa_query)))
2011                         break;
2012
2013                 switch (mgmt->u.action.u.sa_query.action) {
2014                 case WLAN_ACTION_SA_QUERY_REQUEST:
2015                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2016                                 break;
2017                         ieee80211_process_sa_query_req(sdata, mgmt, len);
2018                         goto handled;
2019                 }
2020                 break;
2021         case WLAN_CATEGORY_MESH_PLINK:
2022         case WLAN_CATEGORY_MESH_PATH_SEL:
2023                 if (!ieee80211_vif_is_mesh(&sdata->vif))
2024                         break;
2025                 rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2026                 skb_queue_tail(&sdata->skb_queue, rx->skb);
2027                 ieee80211_queue_work(&local->hw, &sdata->work);
2028                 return RX_QUEUED;
2029         }
2030
2031  invalid:
2032         /*
2033          * For AP mode, hostapd is responsible for handling any action
2034          * frames that we didn't handle, including returning unknown
2035          * ones. For all other modes we will return them to the sender,
2036          * setting the 0x80 bit in the action category, as required by
2037          * 802.11-2007 7.3.1.11.
2038          */
2039         if (sdata->vif.type == NL80211_IFTYPE_AP ||
2040             sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2041                 return RX_DROP_MONITOR;
2042
2043         /*
2044          * Getting here means the kernel doesn't know how to handle
2045          * it, but maybe userspace does ... include returned frames
2046          * so userspace can register for those to know whether ones
2047          * it transmitted were processed or returned.
2048          */
2049         status = IEEE80211_SKB_RXCB(rx->skb);
2050
2051         if (cfg80211_rx_action(rx->sdata->dev, status->freq,
2052                                rx->skb->data, rx->skb->len,
2053                                GFP_ATOMIC))
2054                 goto handled;
2055
2056         /* do not return rejected action frames */
2057         if (mgmt->u.action.category & 0x80)
2058                 return RX_DROP_UNUSABLE;
2059
2060         nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2061                                GFP_ATOMIC);
2062         if (nskb) {
2063                 struct ieee80211_mgmt *mgmt = (void *)nskb->data;
2064
2065                 mgmt->u.action.category |= 0x80;
2066                 memcpy(mgmt->da, mgmt->sa, ETH_ALEN);
2067                 memcpy(mgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2068
2069                 memset(nskb->cb, 0, sizeof(nskb->cb));
2070
2071                 ieee80211_tx_skb(rx->sdata, nskb);
2072         }
2073
2074  handled:
2075         if (rx->sta)
2076                 rx->sta->rx_packets++;
2077         dev_kfree_skb(rx->skb);
2078         return RX_QUEUED;
2079 }
2080
2081 static ieee80211_rx_result debug_noinline
2082 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2083 {
2084         struct ieee80211_sub_if_data *sdata = rx->sdata;
2085         ieee80211_rx_result rxs;
2086         struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2087         __le16 stype;
2088
2089         if (!(rx->flags & IEEE80211_RX_RA_MATCH))
2090                 return RX_DROP_MONITOR;
2091
2092         if (rx->skb->len < 24)
2093                 return RX_DROP_MONITOR;
2094
2095         if (ieee80211_drop_unencrypted_mgmt(rx))
2096                 return RX_DROP_UNUSABLE;
2097
2098         rxs = ieee80211_work_rx_mgmt(rx->sdata, rx->skb);
2099         if (rxs != RX_CONTINUE)
2100                 return rxs;
2101
2102         stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2103
2104         if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2105             sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2106             sdata->vif.type != NL80211_IFTYPE_STATION)
2107                 return RX_DROP_MONITOR;
2108
2109         switch (stype) {
2110         case cpu_to_le16(IEEE80211_STYPE_BEACON):
2111         case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2112                 /* process for all: mesh, mlme, ibss */
2113                 break;
2114         case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2115         case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2116                 /* process only for station */
2117                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2118                         return RX_DROP_MONITOR;
2119                 break;
2120         case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2121         case cpu_to_le16(IEEE80211_STYPE_AUTH):
2122                 /* process only for ibss */
2123                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
2124                         return RX_DROP_MONITOR;
2125                 break;
2126         default:
2127                 return RX_DROP_MONITOR;
2128         }
2129
2130         /* queue up frame and kick off work to process it */
2131         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2132         skb_queue_tail(&sdata->skb_queue, rx->skb);
2133         ieee80211_queue_work(&rx->local->hw, &sdata->work);
2134
2135         return RX_QUEUED;
2136 }
2137
2138 static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr,
2139                                             struct ieee80211_rx_data *rx)
2140 {
2141         int keyidx;
2142         unsigned int hdrlen;
2143
2144         hdrlen = ieee80211_hdrlen(hdr->frame_control);
2145         if (rx->skb->len >= hdrlen + 4)
2146                 keyidx = rx->skb->data[hdrlen + 3] >> 6;
2147         else
2148                 keyidx = -1;
2149
2150         if (!rx->sta) {
2151                 /*
2152                  * Some hardware seem to generate incorrect Michael MIC
2153                  * reports; ignore them to avoid triggering countermeasures.
2154                  */
2155                 return;
2156         }
2157
2158         if (!ieee80211_has_protected(hdr->frame_control))
2159                 return;
2160
2161         if (rx->sdata->vif.type == NL80211_IFTYPE_AP && keyidx) {
2162                 /*
2163                  * APs with pairwise keys should never receive Michael MIC
2164                  * errors for non-zero keyidx because these are reserved for
2165                  * group keys and only the AP is sending real multicast
2166                  * frames in the BSS.
2167                  */
2168                 return;
2169         }
2170
2171         if (!ieee80211_is_data(hdr->frame_control) &&
2172             !ieee80211_is_auth(hdr->frame_control))
2173                 return;
2174
2175         mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL,
2176                                         GFP_ATOMIC);
2177 }
2178
2179 /* TODO: use IEEE80211_RX_FRAGMENTED */
2180 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2181                                         struct ieee80211_rate *rate)
2182 {
2183         struct ieee80211_sub_if_data *sdata;
2184         struct ieee80211_local *local = rx->local;
2185         struct ieee80211_rtap_hdr {
2186                 struct ieee80211_radiotap_header hdr;
2187                 u8 flags;
2188                 u8 rate_or_pad;
2189                 __le16 chan_freq;
2190                 __le16 chan_flags;
2191         } __attribute__ ((packed)) *rthdr;
2192         struct sk_buff *skb = rx->skb, *skb2;
2193         struct net_device *prev_dev = NULL;
2194         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2195
2196         if (status->flag & RX_FLAG_INTERNAL_CMTR)
2197                 goto out_free_skb;
2198
2199         if (skb_headroom(skb) < sizeof(*rthdr) &&
2200             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
2201                 goto out_free_skb;
2202
2203         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
2204         memset(rthdr, 0, sizeof(*rthdr));
2205         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
2206         rthdr->hdr.it_present =
2207                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
2208                             (1 << IEEE80211_RADIOTAP_CHANNEL));
2209
2210         if (rate) {
2211                 rthdr->rate_or_pad = rate->bitrate / 5;
2212                 rthdr->hdr.it_present |=
2213                         cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
2214         }
2215         rthdr->chan_freq = cpu_to_le16(status->freq);
2216
2217         if (status->band == IEEE80211_BAND_5GHZ)
2218                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
2219                                                 IEEE80211_CHAN_5GHZ);
2220         else
2221                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
2222                                                 IEEE80211_CHAN_2GHZ);
2223
2224         skb_set_mac_header(skb, 0);
2225         skb->ip_summed = CHECKSUM_UNNECESSARY;
2226         skb->pkt_type = PACKET_OTHERHOST;
2227         skb->protocol = htons(ETH_P_802_2);
2228
2229         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2230                 if (!ieee80211_sdata_running(sdata))
2231                         continue;
2232
2233                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2234                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2235                         continue;
2236
2237                 if (prev_dev) {
2238                         skb2 = skb_clone(skb, GFP_ATOMIC);
2239                         if (skb2) {
2240                                 skb2->dev = prev_dev;
2241                                 netif_rx(skb2);
2242                         }
2243                 }
2244
2245                 prev_dev = sdata->dev;
2246                 sdata->dev->stats.rx_packets++;
2247                 sdata->dev->stats.rx_bytes += skb->len;
2248         }
2249
2250         if (prev_dev) {
2251                 skb->dev = prev_dev;
2252                 netif_rx(skb);
2253                 skb = NULL;
2254         } else
2255                 goto out_free_skb;
2256
2257         status->flag |= RX_FLAG_INTERNAL_CMTR;
2258         return;
2259
2260  out_free_skb:
2261         dev_kfree_skb(skb);
2262 }
2263
2264
2265 static void ieee80211_invoke_rx_handlers(struct ieee80211_sub_if_data *sdata,
2266                                          struct ieee80211_rx_data *rx,
2267                                          struct sk_buff *skb,
2268                                          struct ieee80211_rate *rate)
2269 {
2270         struct sk_buff_head reorder_release;
2271         ieee80211_rx_result res = RX_DROP_MONITOR;
2272
2273         __skb_queue_head_init(&reorder_release);
2274
2275         rx->skb = skb;
2276         rx->sdata = sdata;
2277
2278 #define CALL_RXH(rxh)                   \
2279         do {                            \
2280                 res = rxh(rx);          \
2281                 if (res != RX_CONTINUE) \
2282                         goto rxh_next;  \
2283         } while (0);
2284
2285         /*
2286          * NB: the rxh_next label works even if we jump
2287          *     to it from here because then the list will
2288          *     be empty, which is a trivial check
2289          */
2290         CALL_RXH(ieee80211_rx_h_passive_scan)
2291         CALL_RXH(ieee80211_rx_h_check)
2292
2293         ieee80211_rx_reorder_ampdu(rx, &reorder_release);
2294
2295         while ((skb = __skb_dequeue(&reorder_release))) {
2296                 /*
2297                  * all the other fields are valid across frames
2298                  * that belong to an aMPDU since they are on the
2299                  * same TID from the same station
2300                  */
2301                 rx->skb = skb;
2302
2303                 CALL_RXH(ieee80211_rx_h_decrypt)
2304                 CALL_RXH(ieee80211_rx_h_check_more_data)
2305                 CALL_RXH(ieee80211_rx_h_sta_process)
2306                 CALL_RXH(ieee80211_rx_h_defragment)
2307                 CALL_RXH(ieee80211_rx_h_ps_poll)
2308                 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2309                 /* must be after MMIC verify so header is counted in MPDU mic */
2310                 CALL_RXH(ieee80211_rx_h_remove_qos_control)
2311                 CALL_RXH(ieee80211_rx_h_amsdu)
2312 #ifdef CONFIG_MAC80211_MESH
2313                 if (ieee80211_vif_is_mesh(&sdata->vif))
2314                         CALL_RXH(ieee80211_rx_h_mesh_fwding);
2315 #endif
2316                 CALL_RXH(ieee80211_rx_h_data)
2317
2318                 /* special treatment -- needs the queue */
2319                 res = ieee80211_rx_h_ctrl(rx, &reorder_release);
2320                 if (res != RX_CONTINUE)
2321                         goto rxh_next;
2322
2323                 CALL_RXH(ieee80211_rx_h_action)
2324                 CALL_RXH(ieee80211_rx_h_mgmt)
2325
2326 #undef CALL_RXH
2327
2328  rxh_next:
2329                 switch (res) {
2330                 case RX_DROP_MONITOR:
2331                         I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2332                         if (rx->sta)
2333                                 rx->sta->rx_dropped++;
2334                         /* fall through */
2335                 case RX_CONTINUE:
2336                         ieee80211_rx_cooked_monitor(rx, rate);
2337                         break;
2338                 case RX_DROP_UNUSABLE:
2339                         I802_DEBUG_INC(sdata->local->rx_handlers_drop);
2340                         if (rx->sta)
2341                                 rx->sta->rx_dropped++;
2342                         dev_kfree_skb(rx->skb);
2343                         break;
2344                 case RX_QUEUED:
2345                         I802_DEBUG_INC(sdata->local->rx_handlers_queued);
2346                         break;
2347                 }
2348         }
2349 }
2350
2351 /* main receive path */
2352
2353 static int prepare_for_handlers(struct ieee80211_sub_if_data *sdata,
2354                                 struct ieee80211_rx_data *rx,
2355                                 struct ieee80211_hdr *hdr)
2356 {
2357         struct sk_buff *skb = rx->skb;
2358         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2359         u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2360         int multicast = is_multicast_ether_addr(hdr->addr1);
2361
2362         switch (sdata->vif.type) {
2363         case NL80211_IFTYPE_STATION:
2364                 if (!bssid && !sdata->u.mgd.use_4addr)
2365                         return 0;
2366                 if (!multicast &&
2367                     compare_ether_addr(sdata->vif.addr, hdr->addr1) != 0) {
2368                         if (!(sdata->dev->flags & IFF_PROMISC))
2369                                 return 0;
2370                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2371                 }
2372                 break;
2373         case NL80211_IFTYPE_ADHOC:
2374                 if (!bssid)
2375                         return 0;
2376                 if (ieee80211_is_beacon(hdr->frame_control)) {
2377                         return 1;
2378                 }
2379                 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2380                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2381                                 return 0;
2382                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2383                 } else if (!multicast &&
2384                            compare_ether_addr(sdata->vif.addr,
2385                                               hdr->addr1) != 0) {
2386                         if (!(sdata->dev->flags & IFF_PROMISC))
2387                                 return 0;
2388                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2389                 } else if (!rx->sta) {
2390                         int rate_idx;
2391                         if (status->flag & RX_FLAG_HT)
2392                                 rate_idx = 0; /* TODO: HT rates */
2393                         else
2394                                 rate_idx = status->rate_idx;
2395                         rx->sta = ieee80211_ibss_add_sta(sdata, bssid,
2396                                         hdr->addr2, BIT(rate_idx), GFP_ATOMIC);
2397                 }
2398                 break;
2399         case NL80211_IFTYPE_MESH_POINT:
2400                 if (!multicast &&
2401                     compare_ether_addr(sdata->vif.addr,
2402                                        hdr->addr1) != 0) {
2403                         if (!(sdata->dev->flags & IFF_PROMISC))
2404                                 return 0;
2405
2406                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2407                 }
2408                 break;
2409         case NL80211_IFTYPE_AP_VLAN:
2410         case NL80211_IFTYPE_AP:
2411                 if (!bssid) {
2412                         if (compare_ether_addr(sdata->vif.addr,
2413                                                hdr->addr1))
2414                                 return 0;
2415                 } else if (!ieee80211_bssid_match(bssid,
2416                                         sdata->vif.addr)) {
2417                         if (!(rx->flags & IEEE80211_RX_IN_SCAN))
2418                                 return 0;
2419                         rx->flags &= ~IEEE80211_RX_RA_MATCH;
2420                 }
2421                 break;
2422         case NL80211_IFTYPE_WDS:
2423                 if (bssid || !ieee80211_is_data(hdr->frame_control))
2424                         return 0;
2425                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2426                         return 0;
2427                 break;
2428         case NL80211_IFTYPE_MONITOR:
2429         case NL80211_IFTYPE_UNSPECIFIED:
2430         case __NL80211_IFTYPE_AFTER_LAST:
2431                 /* should never get here */
2432                 WARN_ON(1);
2433                 break;
2434         }
2435
2436         return 1;
2437 }
2438
2439 /*
2440  * This is the actual Rx frames handler. as it blongs to Rx path it must
2441  * be called with rcu_read_lock protection.
2442  */
2443 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2444                                          struct sk_buff *skb,
2445                                          struct ieee80211_rate *rate)
2446 {
2447         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2448         struct ieee80211_local *local = hw_to_local(hw);
2449         struct ieee80211_sub_if_data *sdata;
2450         struct ieee80211_hdr *hdr;
2451         __le16 fc;
2452         struct ieee80211_rx_data rx;
2453         int prepares;
2454         struct ieee80211_sub_if_data *prev = NULL;
2455         struct sk_buff *skb_new;
2456         struct sta_info *sta, *tmp;
2457         bool found_sta = false;
2458         int err = 0;
2459
2460         fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
2461         memset(&rx, 0, sizeof(rx));
2462         rx.skb = skb;
2463         rx.local = local;
2464
2465         if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
2466                 local->dot11ReceivedFragmentCount++;
2467
2468         if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) ||
2469                      test_bit(SCAN_OFF_CHANNEL, &local->scanning)))
2470                 rx.flags |= IEEE80211_RX_IN_SCAN;
2471
2472         if (ieee80211_is_mgmt(fc))
2473                 err = skb_linearize(skb);
2474         else
2475                 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
2476
2477         if (err) {
2478                 dev_kfree_skb(skb);
2479                 return;
2480         }
2481
2482         hdr = (struct ieee80211_hdr *)skb->data;
2483         ieee80211_parse_qos(&rx);
2484         ieee80211_verify_alignment(&rx);
2485
2486         if (ieee80211_is_data(fc)) {
2487                 for_each_sta_info(local, hdr->addr2, sta, tmp) {
2488                         rx.sta = sta;
2489                         found_sta = true;
2490                         rx.sdata = sta->sdata;
2491
2492                         rx.flags |= IEEE80211_RX_RA_MATCH;
2493                         prepares = prepare_for_handlers(rx.sdata, &rx, hdr);
2494                         if (prepares) {
2495                                 if (status->flag & RX_FLAG_MMIC_ERROR) {
2496                                         if (rx.flags & IEEE80211_RX_RA_MATCH)
2497                                                 ieee80211_rx_michael_mic_report(hdr, &rx);
2498                                 } else
2499                                         prev = rx.sdata;
2500                         }
2501                 }
2502         }
2503         if (!found_sta) {
2504                 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2505                         if (!ieee80211_sdata_running(sdata))
2506                                 continue;
2507
2508                         if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
2509                             sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2510                                 continue;
2511
2512                         /*
2513                          * frame is destined for this interface, but if it's
2514                          * not also for the previous one we handle that after
2515                          * the loop to avoid copying the SKB once too much
2516                          */
2517
2518                         if (!prev) {
2519                                 prev = sdata;
2520                                 continue;
2521                         }
2522
2523                         rx.sta = sta_info_get_bss(prev, hdr->addr2);
2524
2525                         rx.flags |= IEEE80211_RX_RA_MATCH;
2526                         prepares = prepare_for_handlers(prev, &rx, hdr);
2527
2528                         if (!prepares)
2529                                 goto next;
2530
2531                         if (status->flag & RX_FLAG_MMIC_ERROR) {
2532                                 rx.sdata = prev;
2533                                 if (rx.flags & IEEE80211_RX_RA_MATCH)
2534                                         ieee80211_rx_michael_mic_report(hdr,
2535                                                                         &rx);
2536                                 goto next;
2537                         }
2538
2539                         /*
2540                          * frame was destined for the previous interface
2541                          * so invoke RX handlers for it
2542                          */
2543
2544                         skb_new = skb_copy(skb, GFP_ATOMIC);
2545                         if (!skb_new) {
2546                                 if (net_ratelimit())
2547                                         printk(KERN_DEBUG "%s: failed to copy "
2548                                                "multicast frame for %s\n",
2549                                                wiphy_name(local->hw.wiphy),
2550                                                prev->name);
2551                                 goto next;
2552                         }
2553                         ieee80211_invoke_rx_handlers(prev, &rx, skb_new, rate);
2554 next:
2555                         prev = sdata;
2556                 }
2557
2558                 if (prev) {
2559                         rx.sta = sta_info_get_bss(prev, hdr->addr2);
2560
2561                         rx.flags |= IEEE80211_RX_RA_MATCH;
2562                         prepares = prepare_for_handlers(prev, &rx, hdr);
2563
2564                         if (!prepares)
2565                                 prev = NULL;
2566                 }
2567         }
2568         if (prev)
2569                 ieee80211_invoke_rx_handlers(prev, &rx, skb, rate);
2570         else
2571                 dev_kfree_skb(skb);
2572 }
2573
2574 /*
2575  * This is the receive path handler. It is called by a low level driver when an
2576  * 802.11 MPDU is received from the hardware.
2577  */
2578 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
2579 {
2580         struct ieee80211_local *local = hw_to_local(hw);
2581         struct ieee80211_rate *rate = NULL;
2582         struct ieee80211_supported_band *sband;
2583         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2584
2585         WARN_ON_ONCE(softirq_count() == 0);
2586
2587         if (WARN_ON(status->band < 0 ||
2588                     status->band >= IEEE80211_NUM_BANDS))
2589                 goto drop;
2590
2591         sband = local->hw.wiphy->bands[status->band];
2592         if (WARN_ON(!sband))
2593                 goto drop;
2594
2595         /*
2596          * If we're suspending, it is possible although not too likely
2597          * that we'd be receiving frames after having already partially
2598          * quiesced the stack. We can't process such frames then since
2599          * that might, for example, cause stations to be added or other
2600          * driver callbacks be invoked.
2601          */
2602         if (unlikely(local->quiescing || local->suspended))
2603                 goto drop;
2604
2605         /*
2606          * The same happens when we're not even started,
2607          * but that's worth a warning.
2608          */
2609         if (WARN_ON(!local->started))
2610                 goto drop;
2611
2612         if (status->flag & RX_FLAG_HT) {
2613                 /*
2614                  * rate_idx is MCS index, which can be [0-76] as documented on:
2615                  *
2616                  * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
2617                  *
2618                  * Anything else would be some sort of driver or hardware error.
2619                  * The driver should catch hardware errors.
2620                  */
2621                 if (WARN((status->rate_idx < 0 ||
2622                          status->rate_idx > 76),
2623                          "Rate marked as an HT rate but passed "
2624                          "status->rate_idx is not "
2625                          "an MCS index [0-76]: %d (0x%02x)\n",
2626                          status->rate_idx,
2627                          status->rate_idx))
2628                         goto drop;
2629         } else {
2630                 if (WARN_ON(status->rate_idx < 0 ||
2631                             status->rate_idx >= sband->n_bitrates))
2632                         goto drop;
2633                 rate = &sband->bitrates[status->rate_idx];
2634         }
2635
2636         /*
2637          * key references and virtual interfaces are protected using RCU
2638          * and this requires that we are in a read-side RCU section during
2639          * receive processing
2640          */
2641         rcu_read_lock();
2642
2643         /*
2644          * Frames with failed FCS/PLCP checksum are not returned,
2645          * all other frames are returned without radiotap header
2646          * if it was previously present.
2647          * Also, frames with less than 16 bytes are dropped.
2648          */
2649         skb = ieee80211_rx_monitor(local, skb, rate);
2650         if (!skb) {
2651                 rcu_read_unlock();
2652                 return;
2653         }
2654
2655         __ieee80211_rx_handle_packet(hw, skb, rate);
2656
2657         rcu_read_unlock();
2658
2659         return;
2660  drop:
2661         kfree_skb(skb);
2662 }
2663 EXPORT_SYMBOL(ieee80211_rx);
2664
2665 /* This is a version of the rx handler that can be called from hard irq
2666  * context. Post the skb on the queue and schedule the tasklet */
2667 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
2668 {
2669         struct ieee80211_local *local = hw_to_local(hw);
2670
2671         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2672
2673         skb->pkt_type = IEEE80211_RX_MSG;
2674         skb_queue_tail(&local->skb_queue, skb);
2675         tasklet_schedule(&local->tasklet);
2676 }
2677 EXPORT_SYMBOL(ieee80211_rx_irqsafe);