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_MACTIME_MPDU)
  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         if (status->flag & RX_FLAG_HT) /* HT info */
  89                 len += 3;
  90
  91         return len;
  92 }
  93
  94 /*
  95  * ieee80211_add_rx_radiotap_header - add radiotap header
  96  *
  97  * add a radiotap header containing all the fields which the hardware provided.
  98  */
  99 static void
 100 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
 101                                  struct sk_buff *skb,
 102                                  struct ieee80211_rate *rate,
 103                                  int rtap_len)
 104 {
 105         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 106         struct ieee80211_radiotap_header *rthdr;
 107         unsigned char *pos;
 108         u16 rx_flags = 0;
 109
 110         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
 111         memset(rthdr, 0, rtap_len);
 112
 113         /* radiotap header, set always present flags */
 114         rthdr->it_present =
 115                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 116                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
 117                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
 118                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
 119         rthdr->it_len = cpu_to_le16(rtap_len);
 120
 121         pos = (unsigned char *)(rthdr+1);
 122
 123         /* the order of the following fields is important */
 124
 125         /* IEEE80211_RADIOTAP_TSFT */
 126         if (status->flag & RX_FLAG_MACTIME_MPDU) {
 127                 put_unaligned_le64(status->mactime, pos);
 128                 rthdr->it_present |=
 129                         cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
 130                 pos += 8;
 131         }
 132
 133         /* IEEE80211_RADIOTAP_FLAGS */
 134         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 135                 *pos |= IEEE80211_RADIOTAP_F_FCS;
 136         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 137                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
 138         if (status->flag & RX_FLAG_SHORTPRE)
 139                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
 140         pos++;
 141
 142         /* IEEE80211_RADIOTAP_RATE */
 143         if (status->flag & RX_FLAG_HT) {
 144                 /*
 145                  * MCS information is a separate field in radiotap,
 146                  * added below. The byte here is needed as padding
 147                  * for the channel though, so initialise it to 0.
 148                  */
 149                 *pos = 0;
 150         } else {
 151                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
 152                 *pos = rate->bitrate / 5;
 153         }
 154         pos++;
 155
 156         /* IEEE80211_RADIOTAP_CHANNEL */
 157         put_unaligned_le16(status->freq, pos);
 158         pos += 2;
 159         if (status->band == IEEE80211_BAND_5GHZ)
 160                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
 161                                    pos);
 162         else if (status->flag & RX_FLAG_HT)
 163                 put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ,
 164                                    pos);
 165         else if (rate->flags & IEEE80211_RATE_ERP_G)
 166                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
 167                                    pos);
 168         else
 169                 put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
 170                                    pos);
 171         pos += 2;
 172
 173         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
 174         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) {
 175                 *pos = status->signal;
 176                 rthdr->it_present |=
 177                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
 178                 pos++;
 179         }
 180
 181         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
 182
 183         /* IEEE80211_RADIOTAP_ANTENNA */
 184         *pos = status->antenna;
 185         pos++;
 186
 187         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
 188
 189         /* IEEE80211_RADIOTAP_RX_FLAGS */
 190         /* ensure 2 byte alignment for the 2 byte field as required */
 191         if ((pos - (u8 *)rthdr) & 1)
 192                 pos++;
 193         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
 194                 rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
 195         put_unaligned_le16(rx_flags, pos);
 196         pos += 2;
 197
 198         if (status->flag & RX_FLAG_HT) {
 199                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
 200                 *pos++ = IEEE80211_RADIOTAP_MCS_HAVE_MCS |
 201                          IEEE80211_RADIOTAP_MCS_HAVE_GI |
 202                          IEEE80211_RADIOTAP_MCS_HAVE_BW;
 203                 *pos = 0;
 204                 if (status->flag & RX_FLAG_SHORT_GI)
 205                         *pos |= IEEE80211_RADIOTAP_MCS_SGI;
 206                 if (status->flag & RX_FLAG_40MHZ)
 207                         *pos |= IEEE80211_RADIOTAP_MCS_BW_40;
 208                 pos++;
 209                 *pos++ = status->rate_idx;
 210         }
 211 }
 212
 213 /*
 214  * This function copies a received frame to all monitor interfaces and
 215  * returns a cleaned-up SKB that no longer includes the FCS nor the
 216  * radiotap header the driver might have added.
 217  */
 218 static struct sk_buff *
 219 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
 220                      struct ieee80211_rate *rate)
 221 {
 222         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
 223         struct ieee80211_sub_if_data *sdata;
 224         int needed_headroom = 0;
 225         struct sk_buff *skb, *skb2;
 226         struct net_device *prev_dev = NULL;
 227         int present_fcs_len = 0;
 228
 229         /*
 230          * First, we may need to make a copy of the skb because
 231          *  (1) we need to modify it for radiotap (if not present), and
 232          *  (2) the other RX handlers will modify the skb we got.
 233          *
 234          * We don't need to, of course, if we aren't going to return
 235          * the SKB because it has a bad FCS/PLCP checksum.
 236          */
 237
 238         /* room for the radiotap header based on driver features */
 239         needed_headroom = ieee80211_rx_radiotap_len(local, status);
 240
 241         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 242                 present_fcs_len = FCS_LEN;
 243
 244         /* make sure hdr->frame_control is on the linear part */
 245         if (!pskb_may_pull(origskb, 2)) {
 246                 dev_kfree_skb(origskb);
 247                 return NULL;
 248         }
 249
 250         if (!local->monitors) {
 251                 if (should_drop_frame(origskb, present_fcs_len)) {
 252                         dev_kfree_skb(origskb);
 253                         return NULL;
 254                 }
 255
 256                 return remove_monitor_info(local, origskb);
 257         }
 258
 259         if (should_drop_frame(origskb, present_fcs_len)) {
 260                 /* only need to expand headroom if necessary */
 261                 skb = origskb;
 262                 origskb = NULL;
 263
 264                 /*
 265                  * This shouldn't trigger often because most devices have an
 266                  * RX header they pull before we get here, and that should
 267                  * be big enough for our radiotap information. We should
 268                  * probably export the length to drivers so that we can have
 269                  * them allocate enough headroom to start with.
 270                  */
 271                 if (skb_headroom(skb) < needed_headroom &&
 272                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
 273                         dev_kfree_skb(skb);
 274                         return NULL;
 275                 }
 276         } else {
 277                 /*
 278                  * Need to make a copy and possibly remove radiotap header
 279                  * and FCS from the original.
 280                  */
 281                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
 282
 283                 origskb = remove_monitor_info(local, origskb);
 284
 285                 if (!skb)
 286                         return origskb;
 287         }
 288
 289         /* prepend radiotap information */
 290         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom);
 291
 292         skb_reset_mac_header(skb);
 293         skb->ip_summed = CHECKSUM_UNNECESSARY;
 294         skb->pkt_type = PACKET_OTHERHOST;
 295         skb->protocol = htons(ETH_P_802_2);
 296
 297         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 298                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
 299                         continue;
 300
 301                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
 302                         continue;
 303
 304                 if (!ieee80211_sdata_running(sdata))
 305                         continue;
 306
 307                 if (prev_dev) {
 308                         skb2 = skb_clone(skb, GFP_ATOMIC);
 309                         if (skb2) {
 310                                 skb2->dev = prev_dev;
 311                                 netif_receive_skb(skb2);
 312                         }
 313                 }
 314
 315                 prev_dev = sdata->dev;
 316                 sdata->dev->stats.rx_packets++;
 317                 sdata->dev->stats.rx_bytes += skb->len;
 318         }
 319
 320         if (prev_dev) {
 321                 skb->dev = prev_dev;
 322                 netif_receive_skb(skb);
 323         } else
 324                 dev_kfree_skb(skb);
 325
 326         return origskb;
 327 }
 328
 329
 330 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
 331 {
 332         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 333         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 334         int tid, seqno_idx, security_idx;
 335
 336         /* does the frame have a qos control field? */
 337         if (ieee80211_is_data_qos(hdr->frame_control)) {
 338                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 339                 /* frame has qos control */
 340                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
 341                 if (*qc & IEEE80211_QOS_CTL_A_MSDU_PRESENT)
 342                         status->rx_flags |= IEEE80211_RX_AMSDU;
 343
 344                 seqno_idx = tid;
 345                 security_idx = tid;
 346         } else {
 347                 /*
 348                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
 349                  *
 350                  *      Sequence numbers for management frames, QoS data
 351                  *      frames with a broadcast/multicast address in the
 352                  *      Address 1 field, and all non-QoS data frames sent
 353                  *      by QoS STAs are assigned using an additional single
 354                  *      modulo-4096 counter, [...]
 355                  *
 356                  * We also use that counter for non-QoS STAs.
 357                  */
 358                 seqno_idx = NUM_RX_DATA_QUEUES;
 359                 security_idx = 0;
 360                 if (ieee80211_is_mgmt(hdr->frame_control))
 361                         security_idx = NUM_RX_DATA_QUEUES;
 362                 tid = 0;
 363         }
 364
 365         rx->seqno_idx = seqno_idx;
 366         rx->security_idx = security_idx;
 367         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 368          * For now, set skb->priority to 0 for other cases. */
 369         rx->skb->priority = (tid > 7) ? 0 : tid;
 370 }
 371
 372 /**
 373  * DOC: Packet alignment
 374  *
 375  * Drivers always need to pass packets that are aligned to two-byte boundaries
 376  * to the stack.
 377  *
 378  * Additionally, should, if possible, align the payload data in a way that
 379  * guarantees that the contained IP header is aligned to a four-byte
 380  * boundary. In the case of regular frames, this simply means aligning the
 381  * payload to a four-byte boundary (because either the IP header is directly
 382  * contained, or IV/RFC1042 headers that have a length divisible by four are
 383  * in front of it).  If the payload data is not properly aligned and the
 384  * architecture doesn't support efficient unaligned operations, mac80211
 385  * will align the data.
 386  *
 387  * With A-MSDU frames, however, the payload data address must yield two modulo
 388  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
 389  * push the IP header further back to a multiple of four again. Thankfully, the
 390  * specs were sane enough this time around to require padding each A-MSDU
 391  * subframe to a length that is a multiple of four.
 392  *
 393  * Padding like Atheros hardware adds which is between the 802.11 header and
 394  * the payload is not supported, the driver is required to move the 802.11
 395  * header to be directly in front of the payload in that case.
 396  */
 397 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
 398 {
 399 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 400         WARN_ONCE((unsigned long)rx->skb->data & 1,
 401                   "unaligned packet at 0x%p\n", rx->skb->data);
 402 #endif
 403 }
 404
 405
 406 /* rx handlers */
 407
 408 static ieee80211_rx_result debug_noinline
 409 ieee80211_rx_h_passive_scan(struct ieee80211_rx_data *rx)
 410 {
 411         struct ieee80211_local *local = rx->local;
 412         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 413         struct sk_buff *skb = rx->skb;
 414
 415         if (likely(!(status->rx_flags & IEEE80211_RX_IN_SCAN) &&
 416                    !local->sched_scanning))
 417                 return RX_CONTINUE;
 418
 419         if (test_bit(SCAN_HW_SCANNING, &local->scanning) ||
 420             test_bit(SCAN_SW_SCANNING, &local->scanning) ||
 421             local->sched_scanning)
 422                 return ieee80211_scan_rx(rx->sdata, skb);
 423
 424         /* scanning finished during invoking of handlers */
 425         I802_DEBUG_INC(local->rx_handlers_drop_passive_scan);
 426         return RX_DROP_UNUSABLE;
 427 }
 428
 429
 430 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
 431 {
 432         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 433
 434         if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
 435                 return 0;
 436
 437         return ieee80211_is_robust_mgmt_frame(hdr);
 438 }
 439
 440
 441 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
 442 {
 443         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 444
 445         if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
 446                 return 0;
 447
 448         return ieee80211_is_robust_mgmt_frame(hdr);
 449 }
 450
 451
 452 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
 453 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
 454 {
 455         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
 456         struct ieee80211_mmie *mmie;
 457
 458         if (skb->len < 24 + sizeof(*mmie) ||
 459             !is_multicast_ether_addr(hdr->da))
 460                 return -1;
 461
 462         if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
 463                 return -1; /* not a robust management frame */
 464
 465         mmie = (struct ieee80211_mmie *)
 466                 (skb->data + skb->len - sizeof(*mmie));
 467         if (mmie->element_id != WLAN_EID_MMIE ||
 468             mmie->length != sizeof(*mmie) - 2)
 469                 return -1;
 470
 471         return le16_to_cpu(mmie->key_id);
 472 }
 473
 474
 475 static ieee80211_rx_result
 476 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
 477 {
 478         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 479         unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
 480         char *dev_addr = rx->sdata->vif.addr;
 481
 482         if (ieee80211_is_data(hdr->frame_control)) {
 483                 if (is_multicast_ether_addr(hdr->addr1)) {
 484                         if (ieee80211_has_tods(hdr->frame_control) ||
 485                                 !ieee80211_has_fromds(hdr->frame_control))
 486                                 return RX_DROP_MONITOR;
 487                         if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0)
 488                                 return RX_DROP_MONITOR;
 489                 } else {
 490                         if (!ieee80211_has_a4(hdr->frame_control))
 491                                 return RX_DROP_MONITOR;
 492                         if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0)
 493                                 return RX_DROP_MONITOR;
 494                 }
 495         }
 496
 497         /* If there is not an established peer link and this is not a peer link
 498          * establisment frame, beacon or probe, drop the frame.
 499          */
 500
 501         if (!rx->sta || sta_plink_state(rx->sta) != NL80211_PLINK_ESTAB) {
 502                 struct ieee80211_mgmt *mgmt;
 503
 504                 if (!ieee80211_is_mgmt(hdr->frame_control))
 505                         return RX_DROP_MONITOR;
 506
 507                 if (ieee80211_is_action(hdr->frame_control)) {
 508                         u8 category;
 509                         mgmt = (struct ieee80211_mgmt *)hdr;
 510                         category = mgmt->u.action.category;
 511                         if (category != WLAN_CATEGORY_MESH_ACTION &&
 512                                 category != WLAN_CATEGORY_SELF_PROTECTED)
 513                                 return RX_DROP_MONITOR;
 514                         return RX_CONTINUE;
 515                 }
 516
 517                 if (ieee80211_is_probe_req(hdr->frame_control) ||
 518                     ieee80211_is_probe_resp(hdr->frame_control) ||
 519                     ieee80211_is_beacon(hdr->frame_control) ||
 520                     ieee80211_is_auth(hdr->frame_control))
 521                         return RX_CONTINUE;
 522
 523                 return RX_DROP_MONITOR;
 524
 525         }
 526
 527 #define msh_h_get(h, l) ((struct ieee80211s_hdr *) ((u8 *)h + l))
 528
 529         if (ieee80211_is_data(hdr->frame_control) &&
 530             is_multicast_ether_addr(hdr->addr1) &&
 531             mesh_rmc_check(hdr->addr3, msh_h_get(hdr, hdrlen), rx->sdata))
 532                 return RX_DROP_MONITOR;
 533 #undef msh_h_get
 534
 535         return RX_CONTINUE;
 536 }
 537
 538 #define SEQ_MODULO 0x1000
 539 #define SEQ_MASK   0xfff
 540
 541 static inline int seq_less(u16 sq1, u16 sq2)
 542 {
 543         return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
 544 }
 545
 546 static inline u16 seq_inc(u16 sq)
 547 {
 548         return (sq + 1) & SEQ_MASK;
 549 }
 550
 551 static inline u16 seq_sub(u16 sq1, u16 sq2)
 552 {
 553         return (sq1 - sq2) & SEQ_MASK;
 554 }
 555
 556
 557 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
 558                                             struct tid_ampdu_rx *tid_agg_rx,
 559                                             int index)
 560 {
 561         struct ieee80211_local *local = hw_to_local(hw);
 562         struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
 563         struct ieee80211_rx_status *status;
 564
 565         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 566
 567         if (!skb)
 568                 goto no_frame;
 569
 570         /* release the frame from the reorder ring buffer */
 571         tid_agg_rx->stored_mpdu_num--;
 572         tid_agg_rx->reorder_buf[index] = NULL;
 573         status = IEEE80211_SKB_RXCB(skb);
 574         status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE;
 575         skb_queue_tail(&local->rx_skb_queue, skb);
 576
 577 no_frame:
 578         tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
 579 }
 580
 581 static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw,
 582                                              struct tid_ampdu_rx *tid_agg_rx,
 583                                              u16 head_seq_num)
 584 {
 585         int index;
 586
 587         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 588
 589         while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
 590                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
 591                                                         tid_agg_rx->buf_size;
 592                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
 593         }
 594 }
 595
 596 /*
 597  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
 598  * the skb was added to the buffer longer than this time ago, the earlier
 599  * frames that have not yet been received are assumed to be lost and the skb
 600  * can be released for processing. This may also release other skb's from the
 601  * reorder buffer if there are no additional gaps between the frames.
 602  *
 603  * Callers must hold tid_agg_rx->reorder_lock.
 604  */
 605 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
 606
 607 static void ieee80211_sta_reorder_release(struct ieee80211_hw *hw,
 608                                           struct tid_ampdu_rx *tid_agg_rx)
 609 {
 610         int index, j;
 611
 612         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 613
 614         /* release the buffer until next missing frame */
 615         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
 616                                                 tid_agg_rx->buf_size;
 617         if (!tid_agg_rx->reorder_buf[index] &&
 618             tid_agg_rx->stored_mpdu_num > 1) {
 619                 /*
 620                  * No buffers ready to be released, but check whether any
 621                  * frames in the reorder buffer have timed out.
 622                  */
 623                 int skipped = 1;
 624                 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
 625                      j = (j + 1) % tid_agg_rx->buf_size) {
 626                         if (!tid_agg_rx->reorder_buf[j]) {
 627                                 skipped++;
 628                                 continue;
 629                         }
 630                         if (skipped &&
 631                             !time_after(jiffies, tid_agg_rx->reorder_time[j] +
 632                                         HT_RX_REORDER_BUF_TIMEOUT))
 633                                 goto set_release_timer;
 634
 635 #ifdef CONFIG_MAC80211_HT_DEBUG
 636                         if (net_ratelimit())
 637                                 wiphy_debug(hw->wiphy,
 638                                             "release an RX reorder frame due to timeout on earlier frames\n");
 639 #endif
 640                         ieee80211_release_reorder_frame(hw, tid_agg_rx, j);
 641
 642                         /*
 643                          * Increment the head seq# also for the skipped slots.
 644                          */
 645                         tid_agg_rx->head_seq_num =
 646                                 (tid_agg_rx->head_seq_num + skipped) & SEQ_MASK;
 647                         skipped = 0;
 648                 }
 649         } else while (tid_agg_rx->reorder_buf[index]) {
 650                 ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
 651                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
 652                                                         tid_agg_rx->buf_size;
 653         }
 654
 655         if (tid_agg_rx->stored_mpdu_num) {
 656                 j = index = seq_sub(tid_agg_rx->head_seq_num,
 657                                     tid_agg_rx->ssn) % tid_agg_rx->buf_size;
 658
 659                 for (; j != (index - 1) % tid_agg_rx->buf_size;
 660                      j = (j + 1) % tid_agg_rx->buf_size) {
 661                         if (tid_agg_rx->reorder_buf[j])
 662                                 break;
 663                 }
 664
 665  set_release_timer:
 666
 667                 mod_timer(&tid_agg_rx->reorder_timer,
 668                           tid_agg_rx->reorder_time[j] + 1 +
 669                           HT_RX_REORDER_BUF_TIMEOUT);
 670         } else {
 671                 del_timer(&tid_agg_rx->reorder_timer);
 672         }
 673 }
 674
 675 /*
 676  * As this function belongs to the RX path it must be under
 677  * rcu_read_lock protection. It returns false if the frame
 678  * can be processed immediately, true if it was consumed.
 679  */
 680 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
 681                                              struct tid_ampdu_rx *tid_agg_rx,
 682                                              struct sk_buff *skb)
 683 {
 684         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 685         u16 sc = le16_to_cpu(hdr->seq_ctrl);
 686         u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
 687         u16 head_seq_num, buf_size;
 688         int index;
 689         bool ret = true;
 690
 691         spin_lock(&tid_agg_rx->reorder_lock);
 692
 693         buf_size = tid_agg_rx->buf_size;
 694         head_seq_num = tid_agg_rx->head_seq_num;
 695
 696         /* frame with out of date sequence number */
 697         if (seq_less(mpdu_seq_num, head_seq_num)) {
 698                 dev_kfree_skb(skb);
 699                 goto out;
 700         }
 701
 702         /*
 703          * If frame the sequence number exceeds our buffering window
 704          * size release some previous frames to make room for this one.
 705          */
 706         if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
 707                 head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
 708                 /* release stored frames up to new head to stack */
 709                 ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num);
 710         }
 711
 712         /* Now the new frame is always in the range of the reordering buffer */
 713
 714         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size;
 715
 716         /* check if we already stored this frame */
 717         if (tid_agg_rx->reorder_buf[index]) {
 718                 dev_kfree_skb(skb);
 719                 goto out;
 720         }
 721
 722         /*
 723          * If the current MPDU is in the right order and nothing else
 724          * is stored we can process it directly, no need to buffer it.
 725          * If it is first but there's something stored, we may be able
 726          * to release frames after this one.
 727          */
 728         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
 729             tid_agg_rx->stored_mpdu_num == 0) {
 730                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
 731                 ret = false;
 732                 goto out;
 733         }
 734
 735         /* put the frame in the reordering buffer */
 736         tid_agg_rx->reorder_buf[index] = skb;
 737         tid_agg_rx->reorder_time[index] = jiffies;
 738         tid_agg_rx->stored_mpdu_num++;
 739         ieee80211_sta_reorder_release(hw, tid_agg_rx);
 740
 741  out:
 742         spin_unlock(&tid_agg_rx->reorder_lock);
 743         return ret;
 744 }
 745
 746 /*
 747  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
 748  * true if the MPDU was buffered, false if it should be processed.
 749  */
 750 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx)
 751 {
 752         struct sk_buff *skb = rx->skb;
 753         struct ieee80211_local *local = rx->local;
 754         struct ieee80211_hw *hw = &local->hw;
 755         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 756         struct sta_info *sta = rx->sta;
 757         struct tid_ampdu_rx *tid_agg_rx;
 758         u16 sc;
 759         int tid;
 760
 761         if (!ieee80211_is_data_qos(hdr->frame_control))
 762                 goto dont_reorder;
 763
 764         /*
 765          * filter the QoS data rx stream according to
 766          * STA/TID and check if this STA/TID is on aggregation
 767          */
 768
 769         if (!sta)
 770                 goto dont_reorder;
 771
 772         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
 773
 774         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
 775         if (!tid_agg_rx)
 776                 goto dont_reorder;
 777
 778         /* qos null data frames are excluded */
 779         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
 780                 goto dont_reorder;
 781
 782         /* new, potentially un-ordered, ampdu frame - process it */
 783
 784         /* reset session timer */
 785         if (tid_agg_rx->timeout)
 786                 mod_timer(&tid_agg_rx->session_timer,
 787                           TU_TO_EXP_TIME(tid_agg_rx->timeout));
 788
 789         /* if this mpdu is fragmented - terminate rx aggregation session */
 790         sc = le16_to_cpu(hdr->seq_ctrl);
 791         if (sc & IEEE80211_SCTL_FRAG) {
 792                 skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
 793                 skb_queue_tail(&rx->sdata->skb_queue, skb);
 794                 ieee80211_queue_work(&local->hw, &rx->sdata->work);
 795                 return;
 796         }
 797
 798         /*
 799          * No locking needed -- we will only ever process one
 800          * RX packet at a time, and thus own tid_agg_rx. All
 801          * other code manipulating it needs to (and does) make
 802          * sure that we cannot get to it any more before doing
 803          * anything with it.
 804          */
 805         if (ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb))
 806                 return;
 807
 808  dont_reorder:
 809         skb_queue_tail(&local->rx_skb_queue, skb);
 810 }
 811
 812 static ieee80211_rx_result debug_noinline
 813 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
 814 {
 815         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 816         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 817
 818         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 819         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 820                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
 821                              rx->sta->last_seq_ctrl[rx->seqno_idx] ==
 822                              hdr->seq_ctrl)) {
 823                         if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
 824                                 rx->local->dot11FrameDuplicateCount++;
 825                                 rx->sta->num_duplicates++;
 826                         }
 827                         return RX_DROP_UNUSABLE;
 828                 } else
 829                         rx->sta->last_seq_ctrl[rx->seqno_idx] = hdr->seq_ctrl;
 830         }
 831
 832         if (unlikely(rx->skb->len < 16)) {
 833                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 834                 return RX_DROP_MONITOR;
 835         }
 836
 837         /* Drop disallowed frame classes based on STA auth/assoc state;
 838          * IEEE 802.11, Chap 5.5.
 839          *
 840          * mac80211 filters only based on association state, i.e. it drops
 841          * Class 3 frames from not associated stations. hostapd sends
 842          * deauth/disassoc frames when needed. In addition, hostapd is
 843          * responsible for filtering on both auth and assoc states.
 844          */
 845
 846         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
 847                 return ieee80211_rx_mesh_check(rx);
 848
 849         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
 850                       ieee80211_is_pspoll(hdr->frame_control)) &&
 851                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
 852                      rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
 853                      (!rx->sta || !test_sta_flags(rx->sta, WLAN_STA_ASSOC))))
 854                 return RX_DROP_MONITOR;
 855
 856         return RX_CONTINUE;
 857 }
 858
 859
 860 static ieee80211_rx_result debug_noinline
 861 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
 862 {
 863         struct sk_buff *skb = rx->skb;
 864         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 865         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 866         int keyidx;
 867         int hdrlen;
 868         ieee80211_rx_result result = RX_DROP_UNUSABLE;
 869         struct ieee80211_key *sta_ptk = NULL;
 870         int mmie_keyidx = -1;
 871         __le16 fc;
 872
 873         /*
 874          * Key selection 101
 875          *
 876          * There are four types of keys:
 877          *  - GTK (group keys)
 878          *  - IGTK (group keys for management frames)
 879          *  - PTK (pairwise keys)
 880          *  - STK (station-to-station pairwise keys)
 881          *
 882          * When selecting a key, we have to distinguish between multicast
 883          * (including broadcast) and unicast frames, the latter can only
 884          * use PTKs and STKs while the former always use GTKs and IGTKs.
 885          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
 886          * unicast frames can also use key indices like GTKs. Hence, if we
 887          * don't have a PTK/STK we check the key index for a WEP key.
 888          *
 889          * Note that in a regular BSS, multicast frames are sent by the
 890          * AP only, associated stations unicast the frame to the AP first
 891          * which then multicasts it on their behalf.
 892          *
 893          * There is also a slight problem in IBSS mode: GTKs are negotiated
 894          * with each station, that is something we don't currently handle.
 895          * The spec seems to expect that one negotiates the same key with
 896          * every station but there's no such requirement; VLANs could be
 897          * possible.
 898          */
 899
 900         /*
 901          * No point in finding a key and decrypting if the frame is neither
 902          * addressed to us nor a multicast frame.
 903          */
 904         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
 905                 return RX_CONTINUE;
 906
 907         /* start without a key */
 908         rx->key = NULL;
 909
 910         if (rx->sta)
 911                 sta_ptk = rcu_dereference(rx->sta->ptk);
 912
 913         fc = hdr->frame_control;
 914
 915         if (!ieee80211_has_protected(fc))
 916                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
 917
 918         if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
 919                 rx->key = sta_ptk;
 920                 if ((status->flag & RX_FLAG_DECRYPTED) &&
 921                     (status->flag & RX_FLAG_IV_STRIPPED))
 922                         return RX_CONTINUE;
 923                 /* Skip decryption if the frame is not protected. */
 924                 if (!ieee80211_has_protected(fc))
 925                         return RX_CONTINUE;
 926         } else if (mmie_keyidx >= 0) {
 927                 /* Broadcast/multicast robust management frame / BIP */
 928                 if ((status->flag & RX_FLAG_DECRYPTED) &&
 929                     (status->flag & RX_FLAG_IV_STRIPPED))
 930                         return RX_CONTINUE;
 931
 932                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
 933                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
 934                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
 935                 if (rx->sta)
 936                         rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
 937                 if (!rx->key)
 938                         rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
 939         } else if (!ieee80211_has_protected(fc)) {
 940                 /*
 941                  * The frame was not protected, so skip decryption. However, we
 942                  * need to set rx->key if there is a key that could have been
 943                  * used so that the frame may be dropped if encryption would
 944                  * have been expected.
 945                  */
 946                 struct ieee80211_key *key = NULL;
 947                 struct ieee80211_sub_if_data *sdata = rx->sdata;
 948                 int i;
 949
 950                 if (ieee80211_is_mgmt(fc) &&
 951                     is_multicast_ether_addr(hdr->addr1) &&
 952                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
 953                         rx->key = key;
 954                 else {
 955                         if (rx->sta) {
 956                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
 957                                         key = rcu_dereference(rx->sta->gtk[i]);
 958                                         if (key)
 959                                                 break;
 960                                 }
 961                         }
 962                         if (!key) {
 963                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
 964                                         key = rcu_dereference(sdata->keys[i]);
 965                                         if (key)
 966                                                 break;
 967                                 }
 968                         }
 969                         if (key)
 970                                 rx->key = key;
 971                 }
 972                 return RX_CONTINUE;
 973         } else {
 974                 u8 keyid;
 975                 /*
 976                  * The device doesn't give us the IV so we won't be
 977                  * able to look up the key. That's ok though, we
 978                  * don't need to decrypt the frame, we just won't
 979                  * be able to keep statistics accurate.
 980                  * Except for key threshold notifications, should
 981                  * we somehow allow the driver to tell us which key
 982                  * the hardware used if this flag is set?
 983                  */
 984                 if ((status->flag & RX_FLAG_DECRYPTED) &&
 985                     (status->flag & RX_FLAG_IV_STRIPPED))
 986                         return RX_CONTINUE;
 987
 988                 hdrlen = ieee80211_hdrlen(fc);
 989
 990                 if (rx->skb->len < 8 + hdrlen)
 991                         return RX_DROP_UNUSABLE; /* TODO: count this? */
 992
 993                 /*
 994                  * no need to call ieee80211_wep_get_keyidx,
 995                  * it verifies a bunch of things we've done already
 996                  */
 997                 skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
 998                 keyidx = keyid >> 6;
 999
1000                 /* check per-station GTK first, if multicast packet */
1001                 if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
1002                         rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
1003
1004                 /* if not found, try default key */
1005                 if (!rx->key) {
1006                         rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
1007
1008                         /*
1009                          * RSNA-protected unicast frames should always be
1010                          * sent with pairwise or station-to-station keys,
1011                          * but for WEP we allow using a key index as well.
1012                          */
1013                         if (rx->key &&
1014                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1015                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1016                             !is_multicast_ether_addr(hdr->addr1))
1017                                 rx->key = NULL;
1018                 }
1019         }
1020
1021         if (rx->key) {
1022                 rx->key->tx_rx_count++;
1023                 /* TODO: add threshold stuff again */
1024         } else {
1025                 return RX_DROP_MONITOR;
1026         }
1027
1028         if (skb_linearize(rx->skb))
1029                 return RX_DROP_UNUSABLE;
1030         /* the hdr variable is invalid now! */
1031
1032         switch (rx->key->conf.cipher) {
1033         case WLAN_CIPHER_SUITE_WEP40:
1034         case WLAN_CIPHER_SUITE_WEP104:
1035                 /* Check for weak IVs if possible */
1036                 if (rx->sta && ieee80211_is_data(fc) &&
1037                     (!(status->flag & RX_FLAG_IV_STRIPPED) ||
1038                      !(status->flag & RX_FLAG_DECRYPTED)) &&
1039                     ieee80211_wep_is_weak_iv(rx->skb, rx->key))
1040                         rx->sta->wep_weak_iv_count++;
1041
1042                 result = ieee80211_crypto_wep_decrypt(rx);
1043                 break;
1044         case WLAN_CIPHER_SUITE_TKIP:
1045                 result = ieee80211_crypto_tkip_decrypt(rx);
1046                 break;
1047         case WLAN_CIPHER_SUITE_CCMP:
1048                 result = ieee80211_crypto_ccmp_decrypt(rx);
1049                 break;
1050         case WLAN_CIPHER_SUITE_AES_CMAC:
1051                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
1052                 break;
1053         default:
1054                 /*
1055                  * We can reach here only with HW-only algorithms
1056                  * but why didn't it decrypt the frame?!
1057                  */
1058                 return RX_DROP_UNUSABLE;
1059         }
1060
1061         /* either the frame has been decrypted or will be dropped */
1062         status->flag |= RX_FLAG_DECRYPTED;
1063
1064         return result;
1065 }
1066
1067 static ieee80211_rx_result debug_noinline
1068 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1069 {
1070         struct ieee80211_local *local;
1071         struct ieee80211_hdr *hdr;
1072         struct sk_buff *skb;
1073
1074         local = rx->local;
1075         skb = rx->skb;
1076         hdr = (struct ieee80211_hdr *) skb->data;
1077
1078         if (!local->pspolling)
1079                 return RX_CONTINUE;
1080
1081         if (!ieee80211_has_fromds(hdr->frame_control))
1082                 /* this is not from AP */
1083                 return RX_CONTINUE;
1084
1085         if (!ieee80211_is_data(hdr->frame_control))
1086                 return RX_CONTINUE;
1087
1088         if (!ieee80211_has_moredata(hdr->frame_control)) {
1089                 /* AP has no more frames buffered for us */
1090                 local->pspolling = false;
1091                 return RX_CONTINUE;
1092         }
1093
1094         /* more data bit is set, let's request a new frame from the AP */
1095         ieee80211_send_pspoll(local, rx->sdata);
1096
1097         return RX_CONTINUE;
1098 }
1099
1100 static void ap_sta_ps_start(struct sta_info *sta)
1101 {
1102         struct ieee80211_sub_if_data *sdata = sta->sdata;
1103         struct ieee80211_local *local = sdata->local;
1104
1105         atomic_inc(&sdata->bss->num_sta_ps);
1106         set_sta_flags(sta, WLAN_STA_PS_STA);
1107         if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
1108                 drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1109 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1110         printk(KERN_DEBUG "%s: STA %pM aid %d enters power save mode\n",
1111                sdata->name, sta->sta.addr, sta->sta.aid);
1112 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1113 }
1114
1115 static void ap_sta_ps_end(struct sta_info *sta)
1116 {
1117         struct ieee80211_sub_if_data *sdata = sta->sdata;
1118
1119         atomic_dec(&sdata->bss->num_sta_ps);
1120
1121 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1122         printk(KERN_DEBUG "%s: STA %pM aid %d exits power save mode\n",
1123                sdata->name, sta->sta.addr, sta->sta.aid);
1124 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1125
1126         if (test_sta_flags(sta, WLAN_STA_PS_DRIVER)) {
1127 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1128                 printk(KERN_DEBUG "%s: STA %pM aid %d driver-ps-blocked\n",
1129                        sdata->name, sta->sta.addr, sta->sta.aid);
1130 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1131                 return;
1132         }
1133
1134         ieee80211_sta_ps_deliver_wakeup(sta);
1135 }
1136
1137 int ieee80211_sta_ps_transition(struct ieee80211_sta *sta, bool start)
1138 {
1139         struct sta_info *sta_inf = container_of(sta, struct sta_info, sta);
1140         bool in_ps;
1141
1142         WARN_ON(!(sta_inf->local->hw.flags & IEEE80211_HW_AP_LINK_PS));
1143
1144         /* Don't let the same PS state be set twice */
1145         in_ps = test_sta_flags(sta_inf, WLAN_STA_PS_STA);
1146         if ((start && in_ps) || (!start && !in_ps))
1147                 return -EINVAL;
1148
1149         if (start)
1150                 ap_sta_ps_start(sta_inf);
1151         else
1152                 ap_sta_ps_end(sta_inf);
1153
1154         return 0;
1155 }
1156 EXPORT_SYMBOL(ieee80211_sta_ps_transition);
1157
1158 static ieee80211_rx_result debug_noinline
1159 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1160 {
1161         struct sta_info *sta = rx->sta;
1162         struct sk_buff *skb = rx->skb;
1163         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1164         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1165
1166         if (!sta)
1167                 return RX_CONTINUE;
1168
1169         /*
1170          * Update last_rx only for IBSS packets which are for the current
1171          * BSSID to avoid keeping the current IBSS network alive in cases
1172          * where other STAs start using different BSSID.
1173          */
1174         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1175                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1176                                                 NL80211_IFTYPE_ADHOC);
1177                 if (compare_ether_addr(bssid, rx->sdata->u.ibss.bssid) == 0) {
1178                         sta->last_rx = jiffies;
1179                         if (ieee80211_is_data(hdr->frame_control)) {
1180                                 sta->last_rx_rate_idx = status->rate_idx;
1181                                 sta->last_rx_rate_flag = status->flag;
1182                         }
1183                 }
1184         } else if (!is_multicast_ether_addr(hdr->addr1)) {
1185                 /*
1186                  * Mesh beacons will update last_rx when if they are found to
1187                  * match the current local configuration when processed.
1188                  */
1189                 sta->last_rx = jiffies;
1190                 if (ieee80211_is_data(hdr->frame_control)) {
1191                         sta->last_rx_rate_idx = status->rate_idx;
1192                         sta->last_rx_rate_flag = status->flag;
1193                 }
1194         }
1195
1196         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1197                 return RX_CONTINUE;
1198
1199         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1200                 ieee80211_sta_rx_notify(rx->sdata, hdr);
1201
1202         sta->rx_fragments++;
1203         sta->rx_bytes += rx->skb->len;
1204         sta->last_signal = status->signal;
1205         ewma_add(&sta->avg_signal, -status->signal);
1206
1207         /*
1208          * Change STA power saving mode only at the end of a frame
1209          * exchange sequence.
1210          */
1211         if (!(sta->local->hw.flags & IEEE80211_HW_AP_LINK_PS) &&
1212             !ieee80211_has_morefrags(hdr->frame_control) &&
1213             !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1214             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1215              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1216                 if (test_sta_flags(sta, WLAN_STA_PS_STA)) {
1217                         /*
1218                          * Ignore doze->wake transitions that are
1219                          * indicated by non-data frames, the standard
1220                          * is unclear here, but for example going to
1221                          * PS mode and then scanning would cause a
1222                          * doze->wake transition for the probe request,
1223                          * and that is clearly undesirable.
1224                          */
1225                         if (ieee80211_is_data(hdr->frame_control) &&
1226                             !ieee80211_has_pm(hdr->frame_control))
1227                                 ap_sta_ps_end(sta);
1228                 } else {
1229                         if (ieee80211_has_pm(hdr->frame_control))
1230                                 ap_sta_ps_start(sta);
1231                 }
1232         }
1233
1234         /*
1235          * Drop (qos-)data::nullfunc frames silently, since they
1236          * are used only to control station power saving mode.
1237          */
1238         if (ieee80211_is_nullfunc(hdr->frame_control) ||
1239             ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1240                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1241
1242                 /*
1243                  * If we receive a 4-addr nullfunc frame from a STA
1244                  * that was not moved to a 4-addr STA vlan yet, drop
1245                  * the frame to the monitor interface, to make sure
1246                  * that hostapd sees it
1247                  */
1248                 if (ieee80211_has_a4(hdr->frame_control) &&
1249                     (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1250                      (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1251                       !rx->sdata->u.vlan.sta)))
1252                         return RX_DROP_MONITOR;
1253                 /*
1254                  * Update counter and free packet here to avoid
1255                  * counting this as a dropped packed.
1256                  */
1257                 sta->rx_packets++;
1258                 dev_kfree_skb(rx->skb);
1259                 return RX_QUEUED;
1260         }
1261
1262         return RX_CONTINUE;
1263 } /* ieee80211_rx_h_sta_process */
1264
1265 static inline struct ieee80211_fragment_entry *
1266 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1267                          unsigned int frag, unsigned int seq, int rx_queue,
1268                          struct sk_buff **skb)
1269 {
1270         struct ieee80211_fragment_entry *entry;
1271         int idx;
1272
1273         idx = sdata->fragment_next;
1274         entry = &sdata->fragments[sdata->fragment_next++];
1275         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1276                 sdata->fragment_next = 0;
1277
1278         if (!skb_queue_empty(&entry->skb_list)) {
1279 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1280                 struct ieee80211_hdr *hdr =
1281                         (struct ieee80211_hdr *) entry->skb_list.next->data;
1282                 printk(KERN_DEBUG "%s: RX reassembly removed oldest "
1283                        "fragment entry (idx=%d age=%lu seq=%d last_frag=%d "
1284                        "addr1=%pM addr2=%pM\n",
1285                        sdata->name, idx,
1286                        jiffies - entry->first_frag_time, entry->seq,
1287                        entry->last_frag, hdr->addr1, hdr->addr2);
1288 #endif
1289                 __skb_queue_purge(&entry->skb_list);
1290         }
1291
1292         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1293         *skb = NULL;
1294         entry->first_frag_time = jiffies;
1295         entry->seq = seq;
1296         entry->rx_queue = rx_queue;
1297         entry->last_frag = frag;
1298         entry->ccmp = 0;
1299         entry->extra_len = 0;
1300
1301         return entry;
1302 }
1303
1304 static inline struct ieee80211_fragment_entry *
1305 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1306                           unsigned int frag, unsigned int seq,
1307                           int rx_queue, struct ieee80211_hdr *hdr)
1308 {
1309         struct ieee80211_fragment_entry *entry;
1310         int i, idx;
1311
1312         idx = sdata->fragment_next;
1313         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1314                 struct ieee80211_hdr *f_hdr;
1315
1316                 idx--;
1317                 if (idx < 0)
1318                         idx = IEEE80211_FRAGMENT_MAX - 1;
1319
1320                 entry = &sdata->fragments[idx];
1321                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1322                     entry->rx_queue != rx_queue ||
1323                     entry->last_frag + 1 != frag)
1324                         continue;
1325
1326                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1327
1328                 /*
1329                  * Check ftype and addresses are equal, else check next fragment
1330                  */
1331                 if (((hdr->frame_control ^ f_hdr->frame_control) &
1332                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1333                     compare_ether_addr(hdr->addr1, f_hdr->addr1) != 0 ||
1334                     compare_ether_addr(hdr->addr2, f_hdr->addr2) != 0)
1335                         continue;
1336
1337                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1338                         __skb_queue_purge(&entry->skb_list);
1339                         continue;
1340                 }
1341                 return entry;
1342         }
1343
1344         return NULL;
1345 }
1346
1347 static ieee80211_rx_result debug_noinline
1348 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1349 {
1350         struct ieee80211_hdr *hdr;
1351         u16 sc;
1352         __le16 fc;
1353         unsigned int frag, seq;
1354         struct ieee80211_fragment_entry *entry;
1355         struct sk_buff *skb;
1356         struct ieee80211_rx_status *status;
1357
1358         hdr = (struct ieee80211_hdr *)rx->skb->data;
1359         fc = hdr->frame_control;
1360         sc = le16_to_cpu(hdr->seq_ctrl);
1361         frag = sc & IEEE80211_SCTL_FRAG;
1362
1363         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1364                    (rx->skb)->len < 24 ||
1365                    is_multicast_ether_addr(hdr->addr1))) {
1366                 /* not fragmented */
1367                 goto out;
1368         }
1369         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1370
1371         if (skb_linearize(rx->skb))
1372                 return RX_DROP_UNUSABLE;
1373
1374         /*
1375          *  skb_linearize() might change the skb->data and
1376          *  previously cached variables (in this case, hdr) need to
1377          *  be refreshed with the new data.
1378          */
1379         hdr = (struct ieee80211_hdr *)rx->skb->data;
1380         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1381
1382         if (frag == 0) {
1383                 /* This is the first fragment of a new frame. */
1384                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1385                                                  rx->seqno_idx, &(rx->skb));
1386                 if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP &&
1387                     ieee80211_has_protected(fc)) {
1388                         int queue = rx->security_idx;
1389                         /* Store CCMP PN so that we can verify that the next
1390                          * fragment has a sequential PN value. */
1391                         entry->ccmp = 1;
1392                         memcpy(entry->last_pn,
1393                                rx->key->u.ccmp.rx_pn[queue],
1394                                CCMP_PN_LEN);
1395                 }
1396                 return RX_QUEUED;
1397         }
1398
1399         /* This is a fragment for a frame that should already be pending in
1400          * fragment cache. Add this fragment to the end of the pending entry.
1401          */
1402         entry = ieee80211_reassemble_find(rx->sdata, frag, seq,
1403                                           rx->seqno_idx, hdr);
1404         if (!entry) {
1405                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1406                 return RX_DROP_MONITOR;
1407         }
1408
1409         /* Verify that MPDUs within one MSDU have sequential PN values.
1410          * (IEEE 802.11i, 8.3.3.4.5) */
1411         if (entry->ccmp) {
1412                 int i;
1413                 u8 pn[CCMP_PN_LEN], *rpn;
1414                 int queue;
1415                 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP)
1416                         return RX_DROP_UNUSABLE;
1417                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1418                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1419                         pn[i]++;
1420                         if (pn[i])
1421                                 break;
1422                 }
1423                 queue = rx->security_idx;
1424                 rpn = rx->key->u.ccmp.rx_pn[queue];
1425                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1426                         return RX_DROP_UNUSABLE;
1427                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1428         }
1429
1430         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1431         __skb_queue_tail(&entry->skb_list, rx->skb);
1432         entry->last_frag = frag;
1433         entry->extra_len += rx->skb->len;
1434         if (ieee80211_has_morefrags(fc)) {
1435                 rx->skb = NULL;
1436                 return RX_QUEUED;
1437         }
1438
1439         rx->skb = __skb_dequeue(&entry->skb_list);
1440         if (skb_tailroom(rx->skb) < entry->extra_len) {
1441                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1442                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1443                                               GFP_ATOMIC))) {
1444                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1445                         __skb_queue_purge(&entry->skb_list);
1446                         return RX_DROP_UNUSABLE;
1447                 }
1448         }
1449         while ((skb = __skb_dequeue(&entry->skb_list))) {
1450                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1451                 dev_kfree_skb(skb);
1452         }
1453
1454         /* Complete frame has been reassembled - process it now */
1455         status = IEEE80211_SKB_RXCB(rx->skb);
1456         status->rx_flags |= IEEE80211_RX_FRAGMENTED;
1457
1458  out:
1459         if (rx->sta)
1460                 rx->sta->rx_packets++;
1461         if (is_multicast_ether_addr(hdr->addr1))
1462                 rx->local->dot11MulticastReceivedFrameCount++;
1463         else
1464                 ieee80211_led_rx(rx->local);
1465         return RX_CONTINUE;
1466 }
1467
1468 static ieee80211_rx_result debug_noinline
1469 ieee80211_rx_h_ps_poll(struct ieee80211_rx_data *rx)
1470 {
1471         struct ieee80211_sub_if_data *sdata = rx->sdata;
1472         __le16 fc = ((struct ieee80211_hdr *)rx->skb->data)->frame_control;
1473         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1474
1475         if (likely(!rx->sta || !ieee80211_is_pspoll(fc) ||
1476                    !(status->rx_flags & IEEE80211_RX_RA_MATCH)))
1477                 return RX_CONTINUE;
1478
1479         if ((sdata->vif.type != NL80211_IFTYPE_AP) &&
1480             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN))
1481                 return RX_DROP_UNUSABLE;
1482
1483         if (!test_sta_flags(rx->sta, WLAN_STA_PS_DRIVER))
1484                 ieee80211_sta_ps_deliver_poll_response(rx->sta);
1485         else
1486                 set_sta_flags(rx->sta, WLAN_STA_PSPOLL);
1487
1488         /* Free PS Poll skb here instead of returning RX_DROP that would
1489          * count as an dropped frame. */
1490         dev_kfree_skb(rx->skb);
1491
1492         return RX_QUEUED;
1493 }
1494
1495 static ieee80211_rx_result debug_noinline
1496 ieee80211_rx_h_remove_qos_control(struct ieee80211_rx_data *rx)
1497 {
1498         u8 *data = rx->skb->data;
1499         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)data;
1500
1501         if (!ieee80211_is_data_qos(hdr->frame_control))
1502                 return RX_CONTINUE;
1503
1504         /* remove the qos control field, update frame type and meta-data */
1505         memmove(data + IEEE80211_QOS_CTL_LEN, data,
1506                 ieee80211_hdrlen(hdr->frame_control) - IEEE80211_QOS_CTL_LEN);
1507         hdr = (struct ieee80211_hdr *)skb_pull(rx->skb, IEEE80211_QOS_CTL_LEN);
1508         /* change frame type to non QOS */
1509         hdr->frame_control &= ~cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
1510
1511         return RX_CONTINUE;
1512 }
1513
1514 static int
1515 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1516 {
1517         if (unlikely(!rx->sta ||
1518             !test_sta_flags(rx->sta, WLAN_STA_AUTHORIZED)))
1519                 return -EACCES;
1520
1521         return 0;
1522 }
1523
1524 static int
1525 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1526 {
1527         struct sk_buff *skb = rx->skb;
1528         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1529
1530         /*
1531          * Pass through unencrypted frames if the hardware has
1532          * decrypted them already.
1533          */
1534         if (status->flag & RX_FLAG_DECRYPTED)
1535                 return 0;
1536
1537         /* Drop unencrypted frames if key is set. */
1538         if (unlikely(!ieee80211_has_protected(fc) &&
1539                      !ieee80211_is_nullfunc(fc) &&
1540                      ieee80211_is_data(fc) &&
1541                      (rx->key || rx->sdata->drop_unencrypted)))
1542                 return -EACCES;
1543
1544         return 0;
1545 }
1546
1547 static int
1548 ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1549 {
1550         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1551         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1552         __le16 fc = hdr->frame_control;
1553
1554         /*
1555          * Pass through unencrypted frames if the hardware has
1556          * decrypted them already.
1557          */
1558         if (status->flag & RX_FLAG_DECRYPTED)
1559                 return 0;
1560
1561         if (rx->sta && test_sta_flags(rx->sta, WLAN_STA_MFP)) {
1562                 if (unlikely(!ieee80211_has_protected(fc) &&
1563                              ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1564                              rx->key)) {
1565                         if (ieee80211_is_deauth(fc))
1566                                 cfg80211_send_unprot_deauth(rx->sdata->dev,
1567                                                             rx->skb->data,
1568                                                             rx->skb->len);
1569                         else if (ieee80211_is_disassoc(fc))
1570                                 cfg80211_send_unprot_disassoc(rx->sdata->dev,
1571                                                               rx->skb->data,
1572                                                               rx->skb->len);
1573                         return -EACCES;
1574                 }
1575                 /* BIP does not use Protected field, so need to check MMIE */
1576                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1577                              ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
1578                         if (ieee80211_is_deauth(fc))
1579                                 cfg80211_send_unprot_deauth(rx->sdata->dev,
1580                                                             rx->skb->data,
1581                                                             rx->skb->len);
1582                         else if (ieee80211_is_disassoc(fc))
1583                                 cfg80211_send_unprot_disassoc(rx->sdata->dev,
1584                                                               rx->skb->data,
1585                                                               rx->skb->len);
1586                         return -EACCES;
1587                 }
1588                 /*
1589                  * When using MFP, Action frames are not allowed prior to
1590                  * having configured keys.
1591                  */
1592                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1593                              ieee80211_is_robust_mgmt_frame(
1594                                      (struct ieee80211_hdr *) rx->skb->data)))
1595                         return -EACCES;
1596         }
1597
1598         return 0;
1599 }
1600
1601 static int
1602 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx, bool *port_control)
1603 {
1604         struct ieee80211_sub_if_data *sdata = rx->sdata;
1605         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1606         bool check_port_control = false;
1607         struct ethhdr *ehdr;
1608         int ret;
1609
1610         *port_control = false;
1611         if (ieee80211_has_a4(hdr->frame_control) &&
1612             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1613                 return -1;
1614
1615         if (sdata->vif.type == NL80211_IFTYPE_STATION &&
1616             !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) {
1617
1618                 if (!sdata->u.mgd.use_4addr)
1619                         return -1;
1620                 else
1621                         check_port_control = true;
1622         }
1623
1624         if (is_multicast_ether_addr(hdr->addr1) &&
1625             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta)
1626                 return -1;
1627
1628         ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1629         if (ret < 0)
1630                 return ret;
1631
1632         ehdr = (struct ethhdr *) rx->skb->data;
1633         if (ehdr->h_proto == rx->sdata->control_port_protocol)
1634                 *port_control = true;
1635         else if (check_port_control)
1636                 return -1;
1637
1638         return 0;
1639 }
1640
1641 /*
1642  * requires that rx->skb is a frame with ethernet header
1643  */
1644 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1645 {
1646         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1647                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1648         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1649
1650         /*
1651          * Allow EAPOL frames to us/the PAE group address regardless
1652          * of whether the frame was encrypted or not.
1653          */
1654         if (ehdr->h_proto == rx->sdata->control_port_protocol &&
1655             (compare_ether_addr(ehdr->h_dest, rx->sdata->vif.addr) == 0 ||
1656              compare_ether_addr(ehdr->h_dest, pae_group_addr) == 0))
1657                 return true;
1658
1659         if (ieee80211_802_1x_port_control(rx) ||
1660             ieee80211_drop_unencrypted(rx, fc))
1661                 return false;
1662
1663         return true;
1664 }
1665
1666 /*
1667  * requires that rx->skb is a frame with ethernet header
1668  */
1669 static void
1670 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1671 {
1672         struct ieee80211_sub_if_data *sdata = rx->sdata;
1673         struct net_device *dev = sdata->dev;
1674         struct sk_buff *skb, *xmit_skb;
1675         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1676         struct sta_info *dsta;
1677         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1678
1679         skb = rx->skb;
1680         xmit_skb = NULL;
1681
1682         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1683              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1684             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1685             (status->rx_flags & IEEE80211_RX_RA_MATCH) &&
1686             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1687                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1688                         /*
1689                          * send multicast frames both to higher layers in
1690                          * local net stack and back to the wireless medium
1691                          */
1692                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1693                         if (!xmit_skb && net_ratelimit())
1694                                 printk(KERN_DEBUG "%s: failed to clone "
1695                                        "multicast frame\n", dev->name);
1696                 } else {
1697                         dsta = sta_info_get(sdata, skb->data);
1698                         if (dsta) {
1699                                 /*
1700                                  * The destination station is associated to
1701                                  * this AP (in this VLAN), so send the frame
1702                                  * directly to it and do not pass it to local
1703                                  * net stack.
1704                                  */
1705                                 xmit_skb = skb;
1706                                 skb = NULL;
1707                         }
1708                 }
1709         }
1710
1711         if (skb) {
1712                 int align __maybe_unused;
1713
1714 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1715                 /*
1716                  * 'align' will only take the values 0 or 2 here
1717                  * since all frames are required to be aligned
1718                  * to 2-byte boundaries when being passed to
1719                  * mac80211. That also explains the __skb_push()
1720                  * below.
1721                  */
1722                 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1723                 if (align) {
1724                         if (WARN_ON(skb_headroom(skb) < 3)) {
1725                                 dev_kfree_skb(skb);
1726                                 skb = NULL;
1727                         } else {
1728                                 u8 *data = skb->data;
1729                                 size_t len = skb_headlen(skb);
1730                                 skb->data -= align;
1731                                 memmove(skb->data, data, len);
1732                                 skb_set_tail_pointer(skb, len);
1733                         }
1734                 }
1735 #endif
1736
1737                 if (skb) {
1738                         /* deliver to local stack */
1739                         skb->protocol = eth_type_trans(skb, dev);
1740                         memset(skb->cb, 0, sizeof(skb->cb));
1741                         netif_receive_skb(skb);
1742                 }
1743         }
1744
1745         if (xmit_skb) {
1746                 /* send to wireless media */
1747                 xmit_skb->protocol = htons(ETH_P_802_3);
1748                 skb_reset_network_header(xmit_skb);
1749                 skb_reset_mac_header(xmit_skb);
1750                 dev_queue_xmit(xmit_skb);
1751         }
1752 }
1753
1754 static ieee80211_rx_result debug_noinline
1755 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1756 {
1757         struct net_device *dev = rx->sdata->dev;
1758         struct sk_buff *skb = rx->skb;
1759         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1760         __le16 fc = hdr->frame_control;
1761         struct sk_buff_head frame_list;
1762         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1763
1764         if (unlikely(!ieee80211_is_data(fc)))
1765                 return RX_CONTINUE;
1766
1767         if (unlikely(!ieee80211_is_data_present(fc)))
1768                 return RX_DROP_MONITOR;
1769
1770         if (!(status->rx_flags & IEEE80211_RX_AMSDU))
1771                 return RX_CONTINUE;
1772
1773         if (ieee80211_has_a4(hdr->frame_control) &&
1774             rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1775             !rx->sdata->u.vlan.sta)
1776                 return RX_DROP_UNUSABLE;
1777
1778         if (is_multicast_ether_addr(hdr->addr1) &&
1779             ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1780               rx->sdata->u.vlan.sta) ||
1781              (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1782               rx->sdata->u.mgd.use_4addr)))
1783                 return RX_DROP_UNUSABLE;
1784
1785         skb->dev = dev;
1786         __skb_queue_head_init(&frame_list);
1787
1788         if (skb_linearize(skb))
1789                 return RX_DROP_UNUSABLE;
1790
1791         ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1792                                  rx->sdata->vif.type,
1793                                  rx->local->hw.extra_tx_headroom, true);
1794
1795         while (!skb_queue_empty(&frame_list)) {
1796                 rx->skb = __skb_dequeue(&frame_list);
1797
1798                 if (!ieee80211_frame_allowed(rx, fc)) {
1799                         dev_kfree_skb(rx->skb);
1800                         continue;
1801                 }
1802                 dev->stats.rx_packets++;
1803                 dev->stats.rx_bytes += rx->skb->len;
1804
1805                 ieee80211_deliver_skb(rx);
1806         }
1807
1808         return RX_QUEUED;
1809 }
1810
1811 #ifdef CONFIG_MAC80211_MESH
1812 static ieee80211_rx_result
1813 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1814 {
1815         struct ieee80211_hdr *hdr;
1816         struct ieee80211s_hdr *mesh_hdr;
1817         unsigned int hdrlen;
1818         struct sk_buff *skb = rx->skb, *fwd_skb;
1819         struct ieee80211_local *local = rx->local;
1820         struct ieee80211_sub_if_data *sdata = rx->sdata;
1821         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1822
1823         hdr = (struct ieee80211_hdr *) skb->data;
1824         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1825         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1826
1827         if (!ieee80211_is_data(hdr->frame_control))
1828                 return RX_CONTINUE;
1829
1830         if (!mesh_hdr->ttl)
1831                 /* illegal frame */
1832                 return RX_DROP_MONITOR;
1833
1834         if (mesh_hdr->flags & MESH_FLAGS_AE) {
1835                 struct mesh_path *mppath;
1836                 char *proxied_addr;
1837                 char *mpp_addr;
1838
1839                 if (is_multicast_ether_addr(hdr->addr1)) {
1840                         mpp_addr = hdr->addr3;
1841                         proxied_addr = mesh_hdr->eaddr1;
1842                 } else {
1843                         mpp_addr = hdr->addr4;
1844                         proxied_addr = mesh_hdr->eaddr2;
1845                 }
1846
1847                 rcu_read_lock();
1848                 mppath = mpp_path_lookup(proxied_addr, sdata);
1849                 if (!mppath) {
1850                         mpp_path_add(proxied_addr, mpp_addr, sdata);
1851                 } else {
1852                         spin_lock_bh(&mppath->state_lock);
1853                         if (compare_ether_addr(mppath->mpp, mpp_addr) != 0)
1854                                 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
1855                         spin_unlock_bh(&mppath->state_lock);
1856                 }
1857                 rcu_read_unlock();
1858         }
1859
1860         /* Frame has reached destination.  Don't forward */
1861         if (!is_multicast_ether_addr(hdr->addr1) &&
1862             compare_ether_addr(sdata->vif.addr, hdr->addr3) == 0)
1863                 return RX_CONTINUE;
1864
1865         mesh_hdr->ttl--;
1866
1867         if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
1868                 if (!mesh_hdr->ttl)
1869                         IEEE80211_IFSTA_MESH_CTR_INC(&rx->sdata->u.mesh,
1870                                                      dropped_frames_ttl);
1871                 else {
1872                         struct ieee80211_hdr *fwd_hdr;
1873                         struct ieee80211_tx_info *info;
1874
1875                         fwd_skb = skb_copy(skb, GFP_ATOMIC);
1876
1877                         if (!fwd_skb && net_ratelimit())
1878                                 printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
1879                                                    sdata->name);
1880                         if (!fwd_skb)
1881                                 goto out;
1882
1883                         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1884                         memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
1885                         info = IEEE80211_SKB_CB(fwd_skb);
1886                         memset(info, 0, sizeof(*info));
1887                         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1888                         info->control.vif = &rx->sdata->vif;
1889                         skb_set_queue_mapping(skb,
1890                                 ieee80211_select_queue(rx->sdata, fwd_skb));
1891                         ieee80211_set_qos_hdr(local, skb);
1892                         if (is_multicast_ether_addr(fwd_hdr->addr1))
1893                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1894                                                                 fwded_mcast);
1895                         else {
1896                                 int err;
1897                                 /*
1898                                  * Save TA to addr1 to send TA a path error if a
1899                                  * suitable next hop is not found
1900                                  */
1901                                 memcpy(fwd_hdr->addr1, fwd_hdr->addr2,
1902                                                 ETH_ALEN);
1903                                 err = mesh_nexthop_lookup(fwd_skb, sdata);
1904                                 /* Failed to immediately resolve next hop:
1905                                  * fwded frame was dropped or will be added
1906                                  * later to the pending skb queue.  */
1907                                 if (err)
1908                                         return RX_DROP_MONITOR;
1909
1910                                 IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1911                                                                 fwded_unicast);
1912                         }
1913                         IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.mesh,
1914                                                      fwded_frames);
1915                         ieee80211_add_pending_skb(local, fwd_skb);
1916                 }
1917         }
1918
1919  out:
1920         if (is_multicast_ether_addr(hdr->addr1) ||
1921             sdata->dev->flags & IFF_PROMISC)
1922                 return RX_CONTINUE;
1923         else
1924                 return RX_DROP_MONITOR;
1925 }
1926 #endif
1927
1928 static ieee80211_rx_result debug_noinline
1929 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
1930 {
1931         struct ieee80211_sub_if_data *sdata = rx->sdata;
1932         struct ieee80211_local *local = rx->local;
1933         struct net_device *dev = sdata->dev;
1934         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1935         __le16 fc = hdr->frame_control;
1936         bool port_control;
1937         int err;
1938
1939         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
1940                 return RX_CONTINUE;
1941
1942         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
1943                 return RX_DROP_MONITOR;
1944
1945         /*
1946          * Allow the cooked monitor interface of an AP to see 4-addr frames so
1947          * that a 4-addr station can be detected and moved into a separate VLAN
1948          */
1949         if (ieee80211_has_a4(hdr->frame_control) &&
1950             sdata->vif.type == NL80211_IFTYPE_AP)
1951                 return RX_DROP_MONITOR;
1952
1953         err = __ieee80211_data_to_8023(rx, &port_control);
1954         if (unlikely(err))
1955                 return RX_DROP_UNUSABLE;
1956
1957         if (!ieee80211_frame_allowed(rx, fc))
1958                 return RX_DROP_MONITOR;
1959
1960         if (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1961             unlikely(port_control) && sdata->bss) {
1962                 sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
1963                                      u.ap);
1964                 dev = sdata->dev;
1965                 rx->sdata = sdata;
1966         }
1967
1968         rx->skb->dev = dev;
1969
1970         dev->stats.rx_packets++;
1971         dev->stats.rx_bytes += rx->skb->len;
1972
1973         if (local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
1974             !is_multicast_ether_addr(
1975                     ((struct ethhdr *)rx->skb->data)->h_dest) &&
1976             (!local->scanning &&
1977              !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state))) {
1978                         mod_timer(&local->dynamic_ps_timer, jiffies +
1979                          msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
1980         }
1981
1982         ieee80211_deliver_skb(rx);
1983
1984         return RX_QUEUED;
1985 }
1986
1987 static ieee80211_rx_result debug_noinline
1988 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
1989 {
1990         struct ieee80211_local *local = rx->local;
1991         struct ieee80211_hw *hw = &local->hw;
1992         struct sk_buff *skb = rx->skb;
1993         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
1994         struct tid_ampdu_rx *tid_agg_rx;
1995         u16 start_seq_num;
1996         u16 tid;
1997
1998         if (likely(!ieee80211_is_ctl(bar->frame_control)))
1999                 return RX_CONTINUE;
2000
2001         if (ieee80211_is_back_req(bar->frame_control)) {
2002                 struct {
2003                         __le16 control, start_seq_num;
2004                 } __packed bar_data;
2005
2006                 if (!rx->sta)
2007                         return RX_DROP_MONITOR;
2008
2009                 if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
2010                                   &bar_data, sizeof(bar_data)))
2011                         return RX_DROP_MONITOR;
2012
2013                 tid = le16_to_cpu(bar_data.control) >> 12;
2014
2015                 tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
2016                 if (!tid_agg_rx)
2017                         return RX_DROP_MONITOR;
2018
2019                 start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
2020
2021                 /* reset session timer */
2022                 if (tid_agg_rx->timeout)
2023                         mod_timer(&tid_agg_rx->session_timer,
2024                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
2025
2026                 spin_lock(&tid_agg_rx->reorder_lock);
2027                 /* release stored frames up to start of BAR */
2028                 ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num);
2029                 spin_unlock(&tid_agg_rx->reorder_lock);
2030
2031                 kfree_skb(skb);
2032                 return RX_QUEUED;
2033         }
2034
2035         /*
2036          * After this point, we only want management frames,
2037          * so we can drop all remaining control frames to
2038          * cooked monitor interfaces.
2039          */
2040         return RX_DROP_MONITOR;
2041 }
2042
2043 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
2044                                            struct ieee80211_mgmt *mgmt,
2045                                            size_t len)
2046 {
2047         struct ieee80211_local *local = sdata->local;
2048         struct sk_buff *skb;
2049         struct ieee80211_mgmt *resp;
2050
2051         if (compare_ether_addr(mgmt->da, sdata->vif.addr) != 0) {
2052                 /* Not to own unicast address */
2053                 return;
2054         }
2055
2056         if (compare_ether_addr(mgmt->sa, sdata->u.mgd.bssid) != 0 ||
2057             compare_ether_addr(mgmt->bssid, sdata->u.mgd.bssid) != 0) {
2058                 /* Not from the current AP or not associated yet. */
2059                 return;
2060         }
2061
2062         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
2063                 /* Too short SA Query request frame */
2064                 return;
2065         }
2066
2067         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
2068         if (skb == NULL)
2069                 return;
2070
2071         skb_reserve(skb, local->hw.extra_tx_headroom);
2072         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
2073         memset(resp, 0, 24);
2074         memcpy(resp->da, mgmt->sa, ETH_ALEN);
2075         memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
2076         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
2077         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2078                                           IEEE80211_STYPE_ACTION);
2079         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
2080         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
2081         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
2082         memcpy(resp->u.action.u.sa_query.trans_id,
2083                mgmt->u.action.u.sa_query.trans_id,
2084                WLAN_SA_QUERY_TR_ID_LEN);
2085
2086         ieee80211_tx_skb(sdata, skb);
2087 }
2088
2089 static ieee80211_rx_result debug_noinline
2090 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
2091 {
2092         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2093         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2094
2095         /*
2096          * From here on, look only at management frames.
2097          * Data and control frames are already handled,
2098          * and unknown (reserved) frames are useless.
2099          */
2100         if (rx->skb->len < 24)
2101                 return RX_DROP_MONITOR;
2102
2103         if (!ieee80211_is_mgmt(mgmt->frame_control))
2104                 return RX_DROP_MONITOR;
2105
2106         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2107                 return RX_DROP_MONITOR;
2108
2109         if (ieee80211_drop_unencrypted_mgmt(rx))
2110                 return RX_DROP_UNUSABLE;
2111
2112         return RX_CONTINUE;
2113 }
2114
2115 static ieee80211_rx_result debug_noinline
2116 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2117 {
2118         struct ieee80211_local *local = rx->local;
2119         struct ieee80211_sub_if_data *sdata = rx->sdata;
2120         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2121         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2122         int len = rx->skb->len;
2123
2124         if (!ieee80211_is_action(mgmt->frame_control))
2125                 return RX_CONTINUE;
2126
2127         /* drop too small frames */
2128         if (len < IEEE80211_MIN_ACTION_SIZE)
2129                 return RX_DROP_UNUSABLE;
2130
2131         if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC)
2132                 return RX_DROP_UNUSABLE;
2133
2134         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2135                 return RX_DROP_UNUSABLE;
2136
2137         switch (mgmt->u.action.category) {
2138         case WLAN_CATEGORY_BACK:
2139                 /*
2140                  * The aggregation code is not prepared to handle
2141                  * anything but STA/AP due to the BSSID handling;
2142                  * IBSS could work in the code but isn't supported
2143                  * by drivers or the standard.
2144                  */
2145                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2146                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2147                     sdata->vif.type != NL80211_IFTYPE_AP)
2148                         break;
2149
2150                 /* verify action_code is present */
2151                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2152                         break;
2153
2154                 switch (mgmt->u.action.u.addba_req.action_code) {
2155                 case WLAN_ACTION_ADDBA_REQ:
2156                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2157                                    sizeof(mgmt->u.action.u.addba_req)))
2158                                 goto invalid;
2159                         break;
2160                 case WLAN_ACTION_ADDBA_RESP:
2161                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2162                                    sizeof(mgmt->u.action.u.addba_resp)))
2163                                 goto invalid;
2164                         break;
2165                 case WLAN_ACTION_DELBA:
2166                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2167                                    sizeof(mgmt->u.action.u.delba)))
2168                                 goto invalid;
2169                         break;
2170                 default:
2171                         goto invalid;
2172                 }
2173
2174                 goto queue;
2175         case WLAN_CATEGORY_SPECTRUM_MGMT:
2176                 if (local->hw.conf.channel->band != IEEE80211_BAND_5GHZ)
2177                         break;
2178
2179                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2180                         break;
2181
2182                 /* verify action_code is present */
2183                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2184                         break;
2185
2186                 switch (mgmt->u.action.u.measurement.action_code) {
2187                 case WLAN_ACTION_SPCT_MSR_REQ:
2188                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2189                                    sizeof(mgmt->u.action.u.measurement)))
2190                                 break;
2191                         ieee80211_process_measurement_req(sdata, mgmt, len);
2192                         goto handled;
2193                 case WLAN_ACTION_SPCT_CHL_SWITCH:
2194                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2195                                    sizeof(mgmt->u.action.u.chan_switch)))
2196                                 break;
2197
2198                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2199                                 break;
2200
2201                         if (memcmp(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN))
2202                                 break;
2203
2204                         goto queue;
2205                 }
2206                 break;
2207         case WLAN_CATEGORY_SA_QUERY:
2208                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2209                            sizeof(mgmt->u.action.u.sa_query)))
2210                         break;
2211
2212                 switch (mgmt->u.action.u.sa_query.action) {
2213                 case WLAN_ACTION_SA_QUERY_REQUEST:
2214                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2215                                 break;
2216                         ieee80211_process_sa_query_req(sdata, mgmt, len);
2217                         goto handled;
2218                 }
2219                 break;
2220         case WLAN_CATEGORY_MESH_ACTION:
2221                 if (!ieee80211_vif_is_mesh(&sdata->vif))
2222                         break;
2223                 goto queue;
2224         case WLAN_CATEGORY_MESH_PATH_SEL:
2225                 if (!mesh_path_sel_is_hwmp(sdata))
2226                         break;
2227                 goto queue;
2228         }
2229
2230         return RX_CONTINUE;
2231
2232  invalid:
2233         status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
2234         /* will return in the next handlers */
2235         return RX_CONTINUE;
2236
2237  handled:
2238         if (rx->sta)
2239                 rx->sta->rx_packets++;
2240         dev_kfree_skb(rx->skb);
2241         return RX_QUEUED;
2242
2243  queue:
2244         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2245         skb_queue_tail(&sdata->skb_queue, rx->skb);
2246         ieee80211_queue_work(&local->hw, &sdata->work);
2247         if (rx->sta)
2248                 rx->sta->rx_packets++;
2249         return RX_QUEUED;
2250 }
2251
2252 static ieee80211_rx_result debug_noinline
2253 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
2254 {
2255         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2256
2257         /* skip known-bad action frames and return them in the next handler */
2258         if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
2259                 return RX_CONTINUE;
2260
2261         /*
2262          * Getting here means the kernel doesn't know how to handle
2263          * it, but maybe userspace does ... include returned frames
2264          * so userspace can register for those to know whether ones
2265          * it transmitted were processed or returned.
2266          */
2267
2268         if (cfg80211_rx_mgmt(rx->sdata->dev, status->freq,
2269                              rx->skb->data, rx->skb->len,
2270                              GFP_ATOMIC)) {
2271                 if (rx->sta)
2272                         rx->sta->rx_packets++;
2273                 dev_kfree_skb(rx->skb);
2274                 return RX_QUEUED;
2275         }
2276
2277
2278         return RX_CONTINUE;
2279 }
2280
2281 static ieee80211_rx_result debug_noinline
2282 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
2283 {
2284         struct ieee80211_local *local = rx->local;
2285         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2286         struct sk_buff *nskb;
2287         struct ieee80211_sub_if_data *sdata = rx->sdata;
2288         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2289
2290         if (!ieee80211_is_action(mgmt->frame_control))
2291                 return RX_CONTINUE;
2292
2293         /*
2294          * For AP mode, hostapd is responsible for handling any action
2295          * frames that we didn't handle, including returning unknown
2296          * ones. For all other modes we will return them to the sender,
2297          * setting the 0x80 bit in the action category, as required by
2298          * 802.11-2007 7.3.1.11.
2299          * Newer versions of hostapd shall also use the management frame
2300          * registration mechanisms, but older ones still use cooked
2301          * monitor interfaces so push all frames there.
2302          */
2303         if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
2304             (sdata->vif.type == NL80211_IFTYPE_AP ||
2305              sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
2306                 return RX_DROP_MONITOR;
2307
2308         /* do not return rejected action frames */
2309         if (mgmt->u.action.category & 0x80)
2310                 return RX_DROP_UNUSABLE;
2311
2312         nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2313                                GFP_ATOMIC);
2314         if (nskb) {
2315                 struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
2316
2317                 nmgmt->u.action.category |= 0x80;
2318                 memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
2319                 memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2320
2321                 memset(nskb->cb, 0, sizeof(nskb->cb));
2322
2323                 ieee80211_tx_skb(rx->sdata, nskb);
2324         }
2325         dev_kfree_skb(rx->skb);
2326         return RX_QUEUED;
2327 }
2328
2329 static ieee80211_rx_result debug_noinline
2330 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2331 {
2332         struct ieee80211_sub_if_data *sdata = rx->sdata;
2333         ieee80211_rx_result rxs;
2334         struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2335         __le16 stype;
2336
2337         rxs = ieee80211_work_rx_mgmt(rx->sdata, rx->skb);
2338         if (rxs != RX_CONTINUE)
2339                 return rxs;
2340
2341         stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2342
2343         if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2344             sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2345             sdata->vif.type != NL80211_IFTYPE_STATION)
2346                 return RX_DROP_MONITOR;
2347
2348         switch (stype) {
2349         case cpu_to_le16(IEEE80211_STYPE_BEACON):
2350         case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2351                 /* process for all: mesh, mlme, ibss */
2352                 break;
2353         case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2354         case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2355                 if (is_multicast_ether_addr(mgmt->da) &&
2356                     !is_broadcast_ether_addr(mgmt->da))
2357                         return RX_DROP_MONITOR;
2358
2359                 /* process only for station */
2360                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2361                         return RX_DROP_MONITOR;
2362                 break;
2363         case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2364         case cpu_to_le16(IEEE80211_STYPE_AUTH):
2365                 /* process only for ibss */
2366                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
2367                         return RX_DROP_MONITOR;
2368                 break;
2369         default:
2370                 return RX_DROP_MONITOR;
2371         }
2372
2373         /* queue up frame and kick off work to process it */
2374         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2375         skb_queue_tail(&sdata->skb_queue, rx->skb);
2376         ieee80211_queue_work(&rx->local->hw, &sdata->work);
2377         if (rx->sta)
2378                 rx->sta->rx_packets++;
2379
2380         return RX_QUEUED;
2381 }
2382
2383 /* TODO: use IEEE80211_RX_FRAGMENTED */
2384 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2385                                         struct ieee80211_rate *rate)
2386 {
2387         struct ieee80211_sub_if_data *sdata;
2388         struct ieee80211_local *local = rx->local;
2389         struct ieee80211_rtap_hdr {
2390                 struct ieee80211_radiotap_header hdr;
2391                 u8 flags;
2392                 u8 rate_or_pad;
2393                 __le16 chan_freq;
2394                 __le16 chan_flags;
2395         } __packed *rthdr;
2396         struct sk_buff *skb = rx->skb, *skb2;
2397         struct net_device *prev_dev = NULL;
2398         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2399
2400         /*
2401          * If cooked monitor has been processed already, then
2402          * don't do it again. If not, set the flag.
2403          */
2404         if (rx->flags & IEEE80211_RX_CMNTR)
2405                 goto out_free_skb;
2406         rx->flags |= IEEE80211_RX_CMNTR;
2407
2408         if (skb_headroom(skb) < sizeof(*rthdr) &&
2409             pskb_expand_head(skb, sizeof(*rthdr), 0, GFP_ATOMIC))
2410                 goto out_free_skb;
2411
2412         rthdr = (void *)skb_push(skb, sizeof(*rthdr));
2413         memset(rthdr, 0, sizeof(*rthdr));
2414         rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
2415         rthdr->hdr.it_present =
2416                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
2417                             (1 << IEEE80211_RADIOTAP_CHANNEL));
2418
2419         if (rate) {
2420                 rthdr->rate_or_pad = rate->bitrate / 5;
2421                 rthdr->hdr.it_present |=
2422                         cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
2423         }
2424         rthdr->chan_freq = cpu_to_le16(status->freq);
2425
2426         if (status->band == IEEE80211_BAND_5GHZ)
2427                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_OFDM |
2428                                                 IEEE80211_CHAN_5GHZ);
2429         else
2430                 rthdr->chan_flags = cpu_to_le16(IEEE80211_CHAN_DYN |
2431                                                 IEEE80211_CHAN_2GHZ);
2432
2433         skb_set_mac_header(skb, 0);
2434         skb->ip_summed = CHECKSUM_UNNECESSARY;
2435         skb->pkt_type = PACKET_OTHERHOST;
2436         skb->protocol = htons(ETH_P_802_2);
2437
2438         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2439                 if (!ieee80211_sdata_running(sdata))
2440                         continue;
2441
2442                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2443                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2444                         continue;
2445
2446                 if (prev_dev) {
2447                         skb2 = skb_clone(skb, GFP_ATOMIC);
2448                         if (skb2) {
2449                                 skb2->dev = prev_dev;
2450                                 netif_receive_skb(skb2);
2451                         }
2452                 }
2453
2454                 prev_dev = sdata->dev;
2455                 sdata->dev->stats.rx_packets++;
2456                 sdata->dev->stats.rx_bytes += skb->len;
2457         }
2458
2459         if (prev_dev) {
2460                 skb->dev = prev_dev;
2461                 netif_receive_skb(skb);
2462                 return;
2463         }
2464
2465  out_free_skb:
2466         dev_kfree_skb(skb);
2467 }
2468
2469 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
2470                                          ieee80211_rx_result res)
2471 {
2472         switch (res) {
2473         case RX_DROP_MONITOR:
2474                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2475                 if (rx->sta)
2476                         rx->sta->rx_dropped++;
2477                 /* fall through */
2478         case RX_CONTINUE: {
2479                 struct ieee80211_rate *rate = NULL;
2480                 struct ieee80211_supported_band *sband;
2481                 struct ieee80211_rx_status *status;
2482
2483                 status = IEEE80211_SKB_RXCB((rx->skb));
2484
2485                 sband = rx->local->hw.wiphy->bands[status->band];
2486                 if (!(status->flag & RX_FLAG_HT))
2487                         rate = &sband->bitrates[status->rate_idx];
2488
2489                 ieee80211_rx_cooked_monitor(rx, rate);
2490                 break;
2491                 }
2492         case RX_DROP_UNUSABLE:
2493                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2494                 if (rx->sta)
2495                         rx->sta->rx_dropped++;
2496                 dev_kfree_skb(rx->skb);
2497                 break;
2498         case RX_QUEUED:
2499                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
2500                 break;
2501         }
2502 }
2503
2504 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx)
2505 {
2506         ieee80211_rx_result res = RX_DROP_MONITOR;
2507         struct sk_buff *skb;
2508
2509 #define CALL_RXH(rxh)                   \
2510         do {                            \
2511                 res = rxh(rx);          \
2512                 if (res != RX_CONTINUE) \
2513                         goto rxh_next;  \
2514         } while (0);
2515
2516         spin_lock(&rx->local->rx_skb_queue.lock);
2517         if (rx->local->running_rx_handler)
2518                 goto unlock;
2519
2520         rx->local->running_rx_handler = true;
2521
2522         while ((skb = __skb_dequeue(&rx->local->rx_skb_queue))) {
2523                 spin_unlock(&rx->local->rx_skb_queue.lock);
2524
2525                 /*
2526                  * all the other fields are valid across frames
2527                  * that belong to an aMPDU since they are on the
2528                  * same TID from the same station
2529                  */
2530                 rx->skb = skb;
2531
2532                 CALL_RXH(ieee80211_rx_h_decrypt)
2533                 CALL_RXH(ieee80211_rx_h_check_more_data)
2534                 CALL_RXH(ieee80211_rx_h_sta_process)
2535                 CALL_RXH(ieee80211_rx_h_defragment)
2536                 CALL_RXH(ieee80211_rx_h_ps_poll)
2537                 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2538                 /* must be after MMIC verify so header is counted in MPDU mic */
2539                 CALL_RXH(ieee80211_rx_h_remove_qos_control)
2540                 CALL_RXH(ieee80211_rx_h_amsdu)
2541 #ifdef CONFIG_MAC80211_MESH
2542                 if (ieee80211_vif_is_mesh(&rx->sdata->vif))
2543                         CALL_RXH(ieee80211_rx_h_mesh_fwding);
2544 #endif
2545                 CALL_RXH(ieee80211_rx_h_data)
2546                 CALL_RXH(ieee80211_rx_h_ctrl);
2547                 CALL_RXH(ieee80211_rx_h_mgmt_check)
2548                 CALL_RXH(ieee80211_rx_h_action)
2549                 CALL_RXH(ieee80211_rx_h_userspace_mgmt)
2550                 CALL_RXH(ieee80211_rx_h_action_return)
2551                 CALL_RXH(ieee80211_rx_h_mgmt)
2552
2553  rxh_next:
2554                 ieee80211_rx_handlers_result(rx, res);
2555                 spin_lock(&rx->local->rx_skb_queue.lock);
2556 #undef CALL_RXH
2557         }
2558
2559         rx->local->running_rx_handler = false;
2560
2561  unlock:
2562         spin_unlock(&rx->local->rx_skb_queue.lock);
2563 }
2564
2565 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
2566 {
2567         ieee80211_rx_result res = RX_DROP_MONITOR;
2568
2569 #define CALL_RXH(rxh)                   \
2570         do {                            \
2571                 res = rxh(rx);          \
2572                 if (res != RX_CONTINUE) \
2573                         goto rxh_next;  \
2574         } while (0);
2575
2576         CALL_RXH(ieee80211_rx_h_passive_scan)
2577         CALL_RXH(ieee80211_rx_h_check)
2578
2579         ieee80211_rx_reorder_ampdu(rx);
2580
2581         ieee80211_rx_handlers(rx);
2582         return;
2583
2584  rxh_next:
2585         ieee80211_rx_handlers_result(rx, res);
2586
2587 #undef CALL_RXH
2588 }
2589
2590 /*
2591  * This function makes calls into the RX path, therefore
2592  * it has to be invoked under RCU read lock.
2593  */
2594 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
2595 {
2596         struct ieee80211_rx_data rx = {
2597                 .sta = sta,
2598                 .sdata = sta->sdata,
2599                 .local = sta->local,
2600                 /* This is OK -- must be QoS data frame */
2601                 .security_idx = tid,
2602                 .seqno_idx = tid,
2603                 .flags = 0,
2604         };
2605         struct tid_ampdu_rx *tid_agg_rx;
2606
2607         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
2608         if (!tid_agg_rx)
2609                 return;
2610
2611         spin_lock(&tid_agg_rx->reorder_lock);
2612         ieee80211_sta_reorder_release(&sta->local->hw, tid_agg_rx);
2613         spin_unlock(&tid_agg_rx->reorder_lock);
2614
2615         ieee80211_rx_handlers(&rx);
2616 }
2617
2618 /* main receive path */
2619
2620 static int prepare_for_handlers(struct ieee80211_rx_data *rx,
2621                                 struct ieee80211_hdr *hdr)
2622 {
2623         struct ieee80211_sub_if_data *sdata = rx->sdata;
2624         struct sk_buff *skb = rx->skb;
2625         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2626         u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2627         int multicast = is_multicast_ether_addr(hdr->addr1);
2628
2629         switch (sdata->vif.type) {
2630         case NL80211_IFTYPE_STATION:
2631                 if (!bssid && !sdata->u.mgd.use_4addr)
2632                         return 0;
2633                 if (!multicast &&
2634                     compare_ether_addr(sdata->vif.addr, hdr->addr1) != 0) {
2635                         if (!(sdata->dev->flags & IFF_PROMISC) ||
2636                             sdata->u.mgd.use_4addr)
2637                                 return 0;
2638                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2639                 }
2640                 break;
2641         case NL80211_IFTYPE_ADHOC:
2642                 if (!bssid)
2643                         return 0;
2644                 if (ieee80211_is_beacon(hdr->frame_control)) {
2645                         return 1;
2646                 }
2647                 else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2648                         if (!(status->rx_flags & IEEE80211_RX_IN_SCAN))
2649                                 return 0;
2650                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2651                 } else if (!multicast &&
2652                            compare_ether_addr(sdata->vif.addr,
2653                                               hdr->addr1) != 0) {
2654                         if (!(sdata->dev->flags & IFF_PROMISC))
2655                                 return 0;
2656                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2657                 } else if (!rx->sta) {
2658                         int rate_idx;
2659                         if (status->flag & RX_FLAG_HT)
2660                                 rate_idx = 0; /* TODO: HT rates */
2661                         else
2662                                 rate_idx = status->rate_idx;
2663                         rx->sta = ieee80211_ibss_add_sta(sdata, bssid,
2664                                         hdr->addr2, BIT(rate_idx), GFP_ATOMIC);
2665                 }
2666                 break;
2667         case NL80211_IFTYPE_MESH_POINT:
2668                 if (!multicast &&
2669                     compare_ether_addr(sdata->vif.addr,
2670                                        hdr->addr1) != 0) {
2671                         if (!(sdata->dev->flags & IFF_PROMISC))
2672                                 return 0;
2673
2674                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2675                 }
2676                 break;
2677         case NL80211_IFTYPE_AP_VLAN:
2678         case NL80211_IFTYPE_AP:
2679                 if (!bssid) {
2680                         if (compare_ether_addr(sdata->vif.addr,
2681                                                hdr->addr1))
2682                                 return 0;
2683                 } else if (!ieee80211_bssid_match(bssid,
2684                                         sdata->vif.addr)) {
2685                         if (!(status->rx_flags & IEEE80211_RX_IN_SCAN) &&
2686                             !ieee80211_is_beacon(hdr->frame_control))
2687                                 return 0;
2688                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2689                 }
2690                 break;
2691         case NL80211_IFTYPE_WDS:
2692                 if (bssid || !ieee80211_is_data(hdr->frame_control))
2693                         return 0;
2694                 if (compare_ether_addr(sdata->u.wds.remote_addr, hdr->addr2))
2695                         return 0;
2696                 break;
2697         default:
2698                 /* should never get here */
2699                 WARN_ON(1);
2700                 break;
2701         }
2702
2703         return 1;
2704 }
2705
2706 /*
2707  * This function returns whether or not the SKB
2708  * was destined for RX processing or not, which,
2709  * if consume is true, is equivalent to whether
2710  * or not the skb was consumed.
2711  */
2712 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
2713                                             struct sk_buff *skb, bool consume)
2714 {
2715         struct ieee80211_local *local = rx->local;
2716         struct ieee80211_sub_if_data *sdata = rx->sdata;
2717         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2718         struct ieee80211_hdr *hdr = (void *)skb->data;
2719         int prepares;
2720
2721         rx->skb = skb;
2722         status->rx_flags |= IEEE80211_RX_RA_MATCH;
2723         prepares = prepare_for_handlers(rx, hdr);
2724
2725         if (!prepares)
2726                 return false;
2727
2728         if (!consume) {
2729                 skb = skb_copy(skb, GFP_ATOMIC);
2730                 if (!skb) {
2731                         if (net_ratelimit())
2732                                 wiphy_debug(local->hw.wiphy,
2733                                         "failed to copy skb for %s\n",
2734                                         sdata->name);
2735                         return true;
2736                 }
2737
2738                 rx->skb = skb;
2739         }
2740
2741         ieee80211_invoke_rx_handlers(rx);
2742         return true;
2743 }
2744
2745 /*
2746  * This is the actual Rx frames handler. as it blongs to Rx path it must
2747  * be called with rcu_read_lock protection.
2748  */
2749 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2750                                          struct sk_buff *skb)
2751 {
2752         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2753         struct ieee80211_local *local = hw_to_local(hw);
2754         struct ieee80211_sub_if_data *sdata;
2755         struct ieee80211_hdr *hdr;
2756         __le16 fc;
2757         struct ieee80211_rx_data rx;
2758         struct ieee80211_sub_if_data *prev;
2759         struct sta_info *sta, *tmp, *prev_sta;
2760         int err = 0;
2761
2762         fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
2763         memset(&rx, 0, sizeof(rx));
2764         rx.skb = skb;
2765         rx.local = local;
2766
2767         if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
2768                 local->dot11ReceivedFragmentCount++;
2769
2770         if (unlikely(test_bit(SCAN_HW_SCANNING, &local->scanning) ||
2771                      test_bit(SCAN_SW_SCANNING, &local->scanning)))
2772                 status->rx_flags |= IEEE80211_RX_IN_SCAN;
2773
2774         if (ieee80211_is_mgmt(fc))
2775                 err = skb_linearize(skb);
2776         else
2777                 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
2778
2779         if (err) {
2780                 dev_kfree_skb(skb);
2781                 return;
2782         }
2783
2784         hdr = (struct ieee80211_hdr *)skb->data;
2785         ieee80211_parse_qos(&rx);
2786         ieee80211_verify_alignment(&rx);
2787
2788         if (ieee80211_is_data(fc)) {
2789                 prev_sta = NULL;
2790
2791                 for_each_sta_info(local, hdr->addr2, sta, tmp) {
2792                         if (!prev_sta) {
2793                                 prev_sta = sta;
2794                                 continue;
2795                         }
2796
2797                         rx.sta = prev_sta;
2798                         rx.sdata = prev_sta->sdata;
2799                         ieee80211_prepare_and_rx_handle(&rx, skb, false);
2800
2801                         prev_sta = sta;
2802                 }
2803
2804                 if (prev_sta) {
2805                         rx.sta = prev_sta;
2806                         rx.sdata = prev_sta->sdata;
2807
2808                         if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
2809                                 return;
2810                         goto out;
2811                 }
2812         }
2813
2814         prev = NULL;
2815
2816         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2817                 if (!ieee80211_sdata_running(sdata))
2818                         continue;
2819
2820                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
2821                     sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2822                         continue;
2823
2824                 /*
2825                  * frame is destined for this interface, but if it's
2826                  * not also for the previous one we handle that after
2827                  * the loop to avoid copying the SKB once too much
2828                  */
2829
2830                 if (!prev) {
2831                         prev = sdata;
2832                         continue;
2833                 }
2834
2835                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
2836                 rx.sdata = prev;
2837                 ieee80211_prepare_and_rx_handle(&rx, skb, false);
2838
2839                 prev = sdata;
2840         }
2841
2842         if (prev) {
2843                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
2844                 rx.sdata = prev;
2845
2846                 if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
2847                         return;
2848         }
2849
2850  out:
2851         dev_kfree_skb(skb);
2852 }
2853
2854 /*
2855  * This is the receive path handler. It is called by a low level driver when an
2856  * 802.11 MPDU is received from the hardware.
2857  */
2858 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
2859 {
2860         struct ieee80211_local *local = hw_to_local(hw);
2861         struct ieee80211_rate *rate = NULL;
2862         struct ieee80211_supported_band *sband;
2863         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2864
2865         WARN_ON_ONCE(softirq_count() == 0);
2866
2867         if (WARN_ON(status->band < 0 ||
2868                     status->band >= IEEE80211_NUM_BANDS))
2869                 goto drop;
2870
2871         sband = local->hw.wiphy->bands[status->band];
2872         if (WARN_ON(!sband))
2873                 goto drop;
2874
2875         /*
2876          * If we're suspending, it is possible although not too likely
2877          * that we'd be receiving frames after having already partially
2878          * quiesced the stack. We can't process such frames then since
2879          * that might, for example, cause stations to be added or other
2880          * driver callbacks be invoked.
2881          */
2882         if (unlikely(local->quiescing || local->suspended))
2883                 goto drop;
2884
2885         /*
2886          * The same happens when we're not even started,
2887          * but that's worth a warning.
2888          */
2889         if (WARN_ON(!local->started))
2890                 goto drop;
2891
2892         if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
2893                 /*
2894                  * Validate the rate, unless a PLCP error means that
2895                  * we probably can't have a valid rate here anyway.
2896                  */
2897
2898                 if (status->flag & RX_FLAG_HT) {
2899                         /*
2900                          * rate_idx is MCS index, which can be [0-76]
2901                          * as documented on:
2902                          *
2903                          * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
2904                          *
2905                          * Anything else would be some sort of driver or
2906                          * hardware error. The driver should catch hardware
2907                          * errors.
2908                          */
2909                         if (WARN((status->rate_idx < 0 ||
2910                                  status->rate_idx > 76),
2911                                  "Rate marked as an HT rate but passed "
2912                                  "status->rate_idx is not "
2913                                  "an MCS index [0-76]: %d (0x%02x)\n",
2914                                  status->rate_idx,
2915                                  status->rate_idx))
2916                                 goto drop;
2917                 } else {
2918                         if (WARN_ON(status->rate_idx < 0 ||
2919                                     status->rate_idx >= sband->n_bitrates))
2920                                 goto drop;
2921                         rate = &sband->bitrates[status->rate_idx];
2922                 }
2923         }
2924
2925         status->rx_flags = 0;
2926
2927         /*
2928          * key references and virtual interfaces are protected using RCU
2929          * and this requires that we are in a read-side RCU section during
2930          * receive processing
2931          */
2932         rcu_read_lock();
2933
2934         /*
2935          * Frames with failed FCS/PLCP checksum are not returned,
2936          * all other frames are returned without radiotap header
2937          * if it was previously present.
2938          * Also, frames with less than 16 bytes are dropped.
2939          */
2940         skb = ieee80211_rx_monitor(local, skb, rate);
2941         if (!skb) {
2942                 rcu_read_unlock();
2943                 return;
2944         }
2945
2946         ieee80211_tpt_led_trig_rx(local,
2947                         ((struct ieee80211_hdr *)skb->data)->frame_control,
2948                         skb->len);
2949         __ieee80211_rx_handle_packet(hw, skb);
2950
2951         rcu_read_unlock();
2952
2953         return;
2954  drop:
2955         kfree_skb(skb);
2956 }
2957 EXPORT_SYMBOL(ieee80211_rx);
2958
2959 /* This is a version of the rx handler that can be called from hard irq
2960  * context. Post the skb on the queue and schedule the tasklet */
2961 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
2962 {
2963         struct ieee80211_local *local = hw_to_local(hw);
2964
2965         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
2966
2967         skb->pkt_type = IEEE80211_RX_MSG;
2968         skb_queue_tail(&local->skb_queue, skb);
2969         tasklet_schedule(&local->tasklet);
2970 }
2971 EXPORT_SYMBOL(ieee80211_rx_irqsafe);