Pileus Git - ~andy/linux/blob - 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 <linux/export.h>
  20 #include <net/mac80211.h>
  21 #include <net/ieee80211_radiotap.h>
  22 #include <asm/unaligned.h>
  23
  24 #include "ieee80211_i.h"
  25 #include "driver-ops.h"
  26 #include "led.h"
  27 #include "mesh.h"
  28 #include "wep.h"
  29 #include "wpa.h"
  30 #include "tkip.h"
  31 #include "wme.h"
  32 #include "rate.h"
  33
  34 /*
  35  * monitor mode reception
  36  *
  37  * This function cleans up the SKB, i.e. it removes all the stuff
  38  * only useful for monitoring.
  39  */
  40 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
  41                                            struct sk_buff *skb)
  42 {
  43         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
  44                 if (likely(skb->len > FCS_LEN))
  45                         __pskb_trim(skb, skb->len - FCS_LEN);
  46                 else {
  47                         /* driver bug */
  48                         WARN_ON(1);
  49                         dev_kfree_skb(skb);
  50                         skb = NULL;
  51                 }
  52         }
  53
  54         return skb;
  55 }
  56
  57 static inline int should_drop_frame(struct sk_buff *skb,
  58                                     int present_fcs_len)
  59 {
  60         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  61         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  62
  63         if (status->flag & (RX_FLAG_FAILED_FCS_CRC |
  64                             RX_FLAG_FAILED_PLCP_CRC |
  65                             RX_FLAG_AMPDU_IS_ZEROLEN))
  66                 return 1;
  67         if (unlikely(skb->len < 16 + present_fcs_len))
  68                 return 1;
  69         if (ieee80211_is_ctl(hdr->frame_control) &&
  70             !ieee80211_is_pspoll(hdr->frame_control) &&
  71             !ieee80211_is_back_req(hdr->frame_control))
  72                 return 1;
  73         return 0;
  74 }
  75
  76 static int
  77 ieee80211_rx_radiotap_len(struct ieee80211_local *local,
  78                           struct ieee80211_rx_status *status)
  79 {
  80         int len;
  81
  82         /* always present fields */
  83         len = sizeof(struct ieee80211_radiotap_header) + 9;
  84
  85         if (status->flag & RX_FLAG_MACTIME_MPDU)
  86                 len += 8;
  87         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
  88                 len += 1;
  89
  90         if (len & 1) /* padding for RX_FLAGS if necessary */
  91                 len++;
  92
  93         if (status->flag & RX_FLAG_HT) /* HT info */
  94                 len += 3;
  95
  96         if (status->flag & RX_FLAG_AMPDU_DETAILS) {
  97                 /* padding */
  98                 while (len & 3)
  99                         len++;
 100                 len += 8;
 101         }
 102
 103         return len;
 104 }
 105
 106 /*
 107  * ieee80211_add_rx_radiotap_header - add radiotap header
 108  *
 109  * add a radiotap header containing all the fields which the hardware provided.
 110  */
 111 static void
 112 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
 113                                  struct sk_buff *skb,
 114                                  struct ieee80211_rate *rate,
 115                                  int rtap_len, bool has_fcs)
 116 {
 117         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 118         struct ieee80211_radiotap_header *rthdr;
 119         unsigned char *pos;
 120         u16 rx_flags = 0;
 121
 122         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
 123         memset(rthdr, 0, rtap_len);
 124
 125         /* radiotap header, set always present flags */
 126         rthdr->it_present =
 127                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 128                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
 129                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
 130                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
 131         rthdr->it_len = cpu_to_le16(rtap_len);
 132
 133         pos = (unsigned char *)(rthdr+1);
 134
 135         /* the order of the following fields is important */
 136
 137         /* IEEE80211_RADIOTAP_TSFT */
 138         if (status->flag & RX_FLAG_MACTIME_MPDU) {
 139                 put_unaligned_le64(status->mactime, pos);
 140                 rthdr->it_present |=
 141                         cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
 142                 pos += 8;
 143         }
 144
 145         /* IEEE80211_RADIOTAP_FLAGS */
 146         if (has_fcs && (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS))
 147                 *pos |= IEEE80211_RADIOTAP_F_FCS;
 148         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 149                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
 150         if (status->flag & RX_FLAG_SHORTPRE)
 151                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
 152         pos++;
 153
 154         /* IEEE80211_RADIOTAP_RATE */
 155         if (!rate || status->flag & RX_FLAG_HT) {
 156                 /*
 157                  * Without rate information don't add it. If we have,
 158                  * MCS information is a separate field in radiotap,
 159                  * added below. The byte here is needed as padding
 160                  * for the channel though, so initialise it to 0.
 161                  */
 162                 *pos = 0;
 163         } else {
 164                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
 165                 *pos = rate->bitrate / 5;
 166         }
 167         pos++;
 168
 169         /* IEEE80211_RADIOTAP_CHANNEL */
 170         put_unaligned_le16(status->freq, pos);
 171         pos += 2;
 172         if (status->band == IEEE80211_BAND_5GHZ)
 173                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
 174                                    pos);
 175         else if (status->flag & RX_FLAG_HT)
 176                 put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ,
 177                                    pos);
 178         else if (rate && rate->flags & IEEE80211_RATE_ERP_G)
 179                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
 180                                    pos);
 181         else if (rate)
 182                 put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
 183                                    pos);
 184         else
 185                 put_unaligned_le16(IEEE80211_CHAN_2GHZ, pos);
 186         pos += 2;
 187
 188         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
 189         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM &&
 190             !(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
 191                 *pos = status->signal;
 192                 rthdr->it_present |=
 193                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
 194                 pos++;
 195         }
 196
 197         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
 198
 199         /* IEEE80211_RADIOTAP_ANTENNA */
 200         *pos = status->antenna;
 201         pos++;
 202
 203         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
 204
 205         /* IEEE80211_RADIOTAP_RX_FLAGS */
 206         /* ensure 2 byte alignment for the 2 byte field as required */
 207         if ((pos - (u8 *)rthdr) & 1)
 208                 pos++;
 209         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
 210                 rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
 211         put_unaligned_le16(rx_flags, pos);
 212         pos += 2;
 213
 214         if (status->flag & RX_FLAG_HT) {
 215                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
 216                 *pos++ = local->hw.radiotap_mcs_details;
 217                 *pos = 0;
 218                 if (status->flag & RX_FLAG_SHORT_GI)
 219                         *pos |= IEEE80211_RADIOTAP_MCS_SGI;
 220                 if (status->flag & RX_FLAG_40MHZ)
 221                         *pos |= IEEE80211_RADIOTAP_MCS_BW_40;
 222                 if (status->flag & RX_FLAG_HT_GF)
 223                         *pos |= IEEE80211_RADIOTAP_MCS_FMT_GF;
 224                 pos++;
 225                 *pos++ = status->rate_idx;
 226         }
 227
 228         if (status->flag & RX_FLAG_AMPDU_DETAILS) {
 229                 u16 flags = 0;
 230
 231                 /* ensure 4 byte alignment */
 232                 while ((pos - (u8 *)rthdr) & 3)
 233                         pos++;
 234                 rthdr->it_present |=
 235                         cpu_to_le32(1 << IEEE80211_RADIOTAP_AMPDU_STATUS);
 236                 put_unaligned_le32(status->ampdu_reference, pos);
 237                 pos += 4;
 238                 if (status->flag & RX_FLAG_AMPDU_REPORT_ZEROLEN)
 239                         flags |= IEEE80211_RADIOTAP_AMPDU_REPORT_ZEROLEN;
 240                 if (status->flag & RX_FLAG_AMPDU_IS_ZEROLEN)
 241                         flags |= IEEE80211_RADIOTAP_AMPDU_IS_ZEROLEN;
 242                 if (status->flag & RX_FLAG_AMPDU_LAST_KNOWN)
 243                         flags |= IEEE80211_RADIOTAP_AMPDU_LAST_KNOWN;
 244                 if (status->flag & RX_FLAG_AMPDU_IS_LAST)
 245                         flags |= IEEE80211_RADIOTAP_AMPDU_IS_LAST;
 246                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_ERROR)
 247                         flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_ERR;
 248                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
 249                         flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_KNOWN;
 250                 put_unaligned_le16(flags, pos);
 251                 pos += 2;
 252                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
 253                         *pos++ = status->ampdu_delimiter_crc;
 254                 else
 255                         *pos++ = 0;
 256                 *pos++ = 0;
 257         }
 258 }
 259
 260 /*
 261  * This function copies a received frame to all monitor interfaces and
 262  * returns a cleaned-up SKB that no longer includes the FCS nor the
 263  * radiotap header the driver might have added.
 264  */
 265 static struct sk_buff *
 266 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
 267                      struct ieee80211_rate *rate)
 268 {
 269         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
 270         struct ieee80211_sub_if_data *sdata;
 271         int needed_headroom;
 272         struct sk_buff *skb, *skb2;
 273         struct net_device *prev_dev = NULL;
 274         int present_fcs_len = 0;
 275
 276         /*
 277          * First, we may need to make a copy of the skb because
 278          *  (1) we need to modify it for radiotap (if not present), and
 279          *  (2) the other RX handlers will modify the skb we got.
 280          *
 281          * We don't need to, of course, if we aren't going to return
 282          * the SKB because it has a bad FCS/PLCP checksum.
 283          */
 284
 285         /* room for the radiotap header based on driver features */
 286         needed_headroom = ieee80211_rx_radiotap_len(local, status);
 287
 288         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 289                 present_fcs_len = FCS_LEN;
 290
 291         /* make sure hdr->frame_control is on the linear part */
 292         if (!pskb_may_pull(origskb, 2)) {
 293                 dev_kfree_skb(origskb);
 294                 return NULL;
 295         }
 296
 297         if (!local->monitors) {
 298                 if (should_drop_frame(origskb, present_fcs_len)) {
 299                         dev_kfree_skb(origskb);
 300                         return NULL;
 301                 }
 302
 303                 return remove_monitor_info(local, origskb);
 304         }
 305
 306         if (should_drop_frame(origskb, present_fcs_len)) {
 307                 /* only need to expand headroom if necessary */
 308                 skb = origskb;
 309                 origskb = NULL;
 310
 311                 /*
 312                  * This shouldn't trigger often because most devices have an
 313                  * RX header they pull before we get here, and that should
 314                  * be big enough for our radiotap information. We should
 315                  * probably export the length to drivers so that we can have
 316                  * them allocate enough headroom to start with.
 317                  */
 318                 if (skb_headroom(skb) < needed_headroom &&
 319                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
 320                         dev_kfree_skb(skb);
 321                         return NULL;
 322                 }
 323         } else {
 324                 /*
 325                  * Need to make a copy and possibly remove radiotap header
 326                  * and FCS from the original.
 327                  */
 328                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
 329
 330                 origskb = remove_monitor_info(local, origskb);
 331
 332                 if (!skb)
 333                         return origskb;
 334         }
 335
 336         /* prepend radiotap information */
 337         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
 338                                          true);
 339
 340         skb_reset_mac_header(skb);
 341         skb->ip_summed = CHECKSUM_UNNECESSARY;
 342         skb->pkt_type = PACKET_OTHERHOST;
 343         skb->protocol = htons(ETH_P_802_2);
 344
 345         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 346                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
 347                         continue;
 348
 349                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
 350                         continue;
 351
 352                 if (!ieee80211_sdata_running(sdata))
 353                         continue;
 354
 355                 if (prev_dev) {
 356                         skb2 = skb_clone(skb, GFP_ATOMIC);
 357                         if (skb2) {
 358                                 skb2->dev = prev_dev;
 359                                 netif_receive_skb(skb2);
 360                         }
 361                 }
 362
 363                 prev_dev = sdata->dev;
 364                 sdata->dev->stats.rx_packets++;
 365                 sdata->dev->stats.rx_bytes += skb->len;
 366         }
 367
 368         if (prev_dev) {
 369                 skb->dev = prev_dev;
 370                 netif_receive_skb(skb);
 371         } else
 372                 dev_kfree_skb(skb);
 373
 374         return origskb;
 375 }
 376
 377
 378 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
 379 {
 380         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 381         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 382         int tid, seqno_idx, security_idx;
 383
 384         /* does the frame have a qos control field? */
 385         if (ieee80211_is_data_qos(hdr->frame_control)) {
 386                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 387                 /* frame has qos control */
 388                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
 389                 if (*qc & IEEE80211_QOS_CTL_A_MSDU_PRESENT)
 390                         status->rx_flags |= IEEE80211_RX_AMSDU;
 391
 392                 seqno_idx = tid;
 393                 security_idx = tid;
 394         } else {
 395                 /*
 396                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
 397                  *
 398                  *      Sequence numbers for management frames, QoS data
 399                  *      frames with a broadcast/multicast address in the
 400                  *      Address 1 field, and all non-QoS data frames sent
 401                  *      by QoS STAs are assigned using an additional single
 402                  *      modulo-4096 counter, [...]
 403                  *
 404                  * We also use that counter for non-QoS STAs.
 405                  */
 406                 seqno_idx = NUM_RX_DATA_QUEUES;
 407                 security_idx = 0;
 408                 if (ieee80211_is_mgmt(hdr->frame_control))
 409                         security_idx = NUM_RX_DATA_QUEUES;
 410                 tid = 0;
 411         }
 412
 413         rx->seqno_idx = seqno_idx;
 414         rx->security_idx = security_idx;
 415         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 416          * For now, set skb->priority to 0 for other cases. */
 417         rx->skb->priority = (tid > 7) ? 0 : tid;
 418 }
 419
 420 /**
 421  * DOC: Packet alignment
 422  *
 423  * Drivers always need to pass packets that are aligned to two-byte boundaries
 424  * to the stack.
 425  *
 426  * Additionally, should, if possible, align the payload data in a way that
 427  * guarantees that the contained IP header is aligned to a four-byte
 428  * boundary. In the case of regular frames, this simply means aligning the
 429  * payload to a four-byte boundary (because either the IP header is directly
 430  * contained, or IV/RFC1042 headers that have a length divisible by four are
 431  * in front of it).  If the payload data is not properly aligned and the
 432  * architecture doesn't support efficient unaligned operations, mac80211
 433  * will align the data.
 434  *
 435  * With A-MSDU frames, however, the payload data address must yield two modulo
 436  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
 437  * push the IP header further back to a multiple of four again. Thankfully, the
 438  * specs were sane enough this time around to require padding each A-MSDU
 439  * subframe to a length that is a multiple of four.
 440  *
 441  * Padding like Atheros hardware adds which is between the 802.11 header and
 442  * the payload is not supported, the driver is required to move the 802.11
 443  * header to be directly in front of the payload in that case.
 444  */
 445 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
 446 {
 447 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 448         WARN_ONCE((unsigned long)rx->skb->data & 1,
 449                   "unaligned packet at 0x%p\n", rx->skb->data);
 450 #endif
 451 }
 452
 453
 454 /* rx handlers */
 455
 456 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
 457 {
 458         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 459
 460         if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
 461                 return 0;
 462
 463         return ieee80211_is_robust_mgmt_frame(hdr);
 464 }
 465
 466
 467 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
 468 {
 469         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 470
 471         if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
 472                 return 0;
 473
 474         return ieee80211_is_robust_mgmt_frame(hdr);
 475 }
 476
 477
 478 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
 479 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
 480 {
 481         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
 482         struct ieee80211_mmie *mmie;
 483
 484         if (skb->len < 24 + sizeof(*mmie) ||
 485             !is_multicast_ether_addr(hdr->da))
 486                 return -1;
 487
 488         if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
 489                 return -1; /* not a robust management frame */
 490
 491         mmie = (struct ieee80211_mmie *)
 492                 (skb->data + skb->len - sizeof(*mmie));
 493         if (mmie->element_id != WLAN_EID_MMIE ||
 494             mmie->length != sizeof(*mmie) - 2)
 495                 return -1;
 496
 497         return le16_to_cpu(mmie->key_id);
 498 }
 499
 500
 501 static ieee80211_rx_result
 502 ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
 503 {
 504         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 505         char *dev_addr = rx->sdata->vif.addr;
 506
 507         if (ieee80211_is_data(hdr->frame_control)) {
 508                 if (is_multicast_ether_addr(hdr->addr1)) {
 509                         if (ieee80211_has_tods(hdr->frame_control) ||
 510                                 !ieee80211_has_fromds(hdr->frame_control))
 511                                 return RX_DROP_MONITOR;
 512                         if (ether_addr_equal(hdr->addr3, dev_addr))
 513                                 return RX_DROP_MONITOR;
 514                 } else {
 515                         if (!ieee80211_has_a4(hdr->frame_control))
 516                                 return RX_DROP_MONITOR;
 517                         if (ether_addr_equal(hdr->addr4, dev_addr))
 518                                 return RX_DROP_MONITOR;
 519                 }
 520         }
 521
 522         /* If there is not an established peer link and this is not a peer link
 523          * establisment frame, beacon or probe, drop the frame.
 524          */
 525
 526         if (!rx->sta || sta_plink_state(rx->sta) != NL80211_PLINK_ESTAB) {
 527                 struct ieee80211_mgmt *mgmt;
 528
 529                 if (!ieee80211_is_mgmt(hdr->frame_control))
 530                         return RX_DROP_MONITOR;
 531
 532                 if (ieee80211_is_action(hdr->frame_control)) {
 533                         u8 category;
 534                         mgmt = (struct ieee80211_mgmt *)hdr;
 535                         category = mgmt->u.action.category;
 536                         if (category != WLAN_CATEGORY_MESH_ACTION &&
 537                                 category != WLAN_CATEGORY_SELF_PROTECTED)
 538                                 return RX_DROP_MONITOR;
 539                         return RX_CONTINUE;
 540                 }
 541
 542                 if (ieee80211_is_probe_req(hdr->frame_control) ||
 543                     ieee80211_is_probe_resp(hdr->frame_control) ||
 544                     ieee80211_is_beacon(hdr->frame_control) ||
 545                     ieee80211_is_auth(hdr->frame_control))
 546                         return RX_CONTINUE;
 547
 548                 return RX_DROP_MONITOR;
 549
 550         }
 551
 552         return RX_CONTINUE;
 553 }
 554
 555 #define SEQ_MODULO 0x1000
 556 #define SEQ_MASK   0xfff
 557
 558 static inline int seq_less(u16 sq1, u16 sq2)
 559 {
 560         return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
 561 }
 562
 563 static inline u16 seq_inc(u16 sq)
 564 {
 565         return (sq + 1) & SEQ_MASK;
 566 }
 567
 568 static inline u16 seq_sub(u16 sq1, u16 sq2)
 569 {
 570         return (sq1 - sq2) & SEQ_MASK;
 571 }
 572
 573
 574 static void ieee80211_release_reorder_frame(struct ieee80211_sub_if_data *sdata,
 575                                             struct tid_ampdu_rx *tid_agg_rx,
 576                                             int index)
 577 {
 578         struct ieee80211_local *local = sdata->local;
 579         struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
 580         struct ieee80211_rx_status *status;
 581
 582         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 583
 584         if (!skb)
 585                 goto no_frame;
 586
 587         /* release the frame from the reorder ring buffer */
 588         tid_agg_rx->stored_mpdu_num--;
 589         tid_agg_rx->reorder_buf[index] = NULL;
 590         status = IEEE80211_SKB_RXCB(skb);
 591         status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE;
 592         skb_queue_tail(&local->rx_skb_queue, skb);
 593
 594 no_frame:
 595         tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
 596 }
 597
 598 static void ieee80211_release_reorder_frames(struct ieee80211_sub_if_data *sdata,
 599                                              struct tid_ampdu_rx *tid_agg_rx,
 600                                              u16 head_seq_num)
 601 {
 602         int index;
 603
 604         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 605
 606         while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
 607                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
 608                                                         tid_agg_rx->buf_size;
 609                 ieee80211_release_reorder_frame(sdata, tid_agg_rx, index);
 610         }
 611 }
 612
 613 /*
 614  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
 615  * the skb was added to the buffer longer than this time ago, the earlier
 616  * frames that have not yet been received are assumed to be lost and the skb
 617  * can be released for processing. This may also release other skb's from the
 618  * reorder buffer if there are no additional gaps between the frames.
 619  *
 620  * Callers must hold tid_agg_rx->reorder_lock.
 621  */
 622 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
 623
 624 static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata,
 625                                           struct tid_ampdu_rx *tid_agg_rx)
 626 {
 627         int index, j;
 628
 629         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 630
 631         /* release the buffer until next missing frame */
 632         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
 633                                                 tid_agg_rx->buf_size;
 634         if (!tid_agg_rx->reorder_buf[index] &&
 635             tid_agg_rx->stored_mpdu_num) {
 636                 /*
 637                  * No buffers ready to be released, but check whether any
 638                  * frames in the reorder buffer have timed out.
 639                  */
 640                 int skipped = 1;
 641                 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
 642                      j = (j + 1) % tid_agg_rx->buf_size) {
 643                         if (!tid_agg_rx->reorder_buf[j]) {
 644                                 skipped++;
 645                                 continue;
 646                         }
 647                         if (skipped &&
 648                             !time_after(jiffies, tid_agg_rx->reorder_time[j] +
 649                                         HT_RX_REORDER_BUF_TIMEOUT))
 650                                 goto set_release_timer;
 651
 652                         ht_dbg_ratelimited(sdata,
 653                                            "release an RX reorder frame due to timeout on earlier frames\n");
 654                         ieee80211_release_reorder_frame(sdata, tid_agg_rx, j);
 655
 656                         /*
 657                          * Increment the head seq# also for the skipped slots.
 658                          */
 659                         tid_agg_rx->head_seq_num =
 660                                 (tid_agg_rx->head_seq_num + skipped) & SEQ_MASK;
 661                         skipped = 0;
 662                 }
 663         } else while (tid_agg_rx->reorder_buf[index]) {
 664                 ieee80211_release_reorder_frame(sdata, tid_agg_rx, index);
 665                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
 666                                                         tid_agg_rx->buf_size;
 667         }
 668
 669         if (tid_agg_rx->stored_mpdu_num) {
 670                 j = index = seq_sub(tid_agg_rx->head_seq_num,
 671                                     tid_agg_rx->ssn) % tid_agg_rx->buf_size;
 672
 673                 for (; j != (index - 1) % tid_agg_rx->buf_size;
 674                      j = (j + 1) % tid_agg_rx->buf_size) {
 675                         if (tid_agg_rx->reorder_buf[j])
 676                                 break;
 677                 }
 678
 679  set_release_timer:
 680
 681                 mod_timer(&tid_agg_rx->reorder_timer,
 682                           tid_agg_rx->reorder_time[j] + 1 +
 683                           HT_RX_REORDER_BUF_TIMEOUT);
 684         } else {
 685                 del_timer(&tid_agg_rx->reorder_timer);
 686         }
 687 }
 688
 689 /*
 690  * As this function belongs to the RX path it must be under
 691  * rcu_read_lock protection. It returns false if the frame
 692  * can be processed immediately, true if it was consumed.
 693  */
 694 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_sub_if_data *sdata,
 695                                              struct tid_ampdu_rx *tid_agg_rx,
 696                                              struct sk_buff *skb)
 697 {
 698         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 699         u16 sc = le16_to_cpu(hdr->seq_ctrl);
 700         u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
 701         u16 head_seq_num, buf_size;
 702         int index;
 703         bool ret = true;
 704
 705         spin_lock(&tid_agg_rx->reorder_lock);
 706
 707         buf_size = tid_agg_rx->buf_size;
 708         head_seq_num = tid_agg_rx->head_seq_num;
 709
 710         /* frame with out of date sequence number */
 711         if (seq_less(mpdu_seq_num, head_seq_num)) {
 712                 dev_kfree_skb(skb);
 713                 goto out;
 714         }
 715
 716         /*
 717          * If frame the sequence number exceeds our buffering window
 718          * size release some previous frames to make room for this one.
 719          */
 720         if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
 721                 head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
 722                 /* release stored frames up to new head to stack */
 723                 ieee80211_release_reorder_frames(sdata, tid_agg_rx,
 724                                                  head_seq_num);
 725         }
 726
 727         /* Now the new frame is always in the range of the reordering buffer */
 728
 729         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size;
 730
 731         /* check if we already stored this frame */
 732         if (tid_agg_rx->reorder_buf[index]) {
 733                 dev_kfree_skb(skb);
 734                 goto out;
 735         }
 736
 737         /*
 738          * If the current MPDU is in the right order and nothing else
 739          * is stored we can process it directly, no need to buffer it.
 740          * If it is first but there's something stored, we may be able
 741          * to release frames after this one.
 742          */
 743         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
 744             tid_agg_rx->stored_mpdu_num == 0) {
 745                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
 746                 ret = false;
 747                 goto out;
 748         }
 749
 750         /* put the frame in the reordering buffer */
 751         tid_agg_rx->reorder_buf[index] = skb;
 752         tid_agg_rx->reorder_time[index] = jiffies;
 753         tid_agg_rx->stored_mpdu_num++;
 754         ieee80211_sta_reorder_release(sdata, tid_agg_rx);
 755
 756  out:
 757         spin_unlock(&tid_agg_rx->reorder_lock);
 758         return ret;
 759 }
 760
 761 /*
 762  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
 763  * true if the MPDU was buffered, false if it should be processed.
 764  */
 765 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx)
 766 {
 767         struct sk_buff *skb = rx->skb;
 768         struct ieee80211_local *local = rx->local;
 769         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 770         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 771         struct sta_info *sta = rx->sta;
 772         struct tid_ampdu_rx *tid_agg_rx;
 773         u16 sc;
 774         u8 tid, ack_policy;
 775
 776         if (!ieee80211_is_data_qos(hdr->frame_control))
 777                 goto dont_reorder;
 778
 779         /*
 780          * filter the QoS data rx stream according to
 781          * STA/TID and check if this STA/TID is on aggregation
 782          */
 783
 784         if (!sta)
 785                 goto dont_reorder;
 786
 787         ack_policy = *ieee80211_get_qos_ctl(hdr) &
 788                      IEEE80211_QOS_CTL_ACK_POLICY_MASK;
 789         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
 790
 791         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
 792         if (!tid_agg_rx)
 793                 goto dont_reorder;
 794
 795         /* qos null data frames are excluded */
 796         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
 797                 goto dont_reorder;
 798
 799         /* not part of a BA session */
 800         if (ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
 801             ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_NORMAL)
 802                 goto dont_reorder;
 803
 804         /* not actually part of this BA session */
 805         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
 806                 goto dont_reorder;
 807
 808         /* new, potentially un-ordered, ampdu frame - process it */
 809
 810         /* reset session timer */
 811         if (tid_agg_rx->timeout)
 812                 tid_agg_rx->last_rx = jiffies;
 813
 814         /* if this mpdu is fragmented - terminate rx aggregation session */
 815         sc = le16_to_cpu(hdr->seq_ctrl);
 816         if (sc & IEEE80211_SCTL_FRAG) {
 817                 skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
 818                 skb_queue_tail(&rx->sdata->skb_queue, skb);
 819                 ieee80211_queue_work(&local->hw, &rx->sdata->work);
 820                 return;
 821         }
 822
 823         /*
 824          * No locking needed -- we will only ever process one
 825          * RX packet at a time, and thus own tid_agg_rx. All
 826          * other code manipulating it needs to (and does) make
 827          * sure that we cannot get to it any more before doing
 828          * anything with it.
 829          */
 830         if (ieee80211_sta_manage_reorder_buf(rx->sdata, tid_agg_rx, skb))
 831                 return;
 832
 833  dont_reorder:
 834         skb_queue_tail(&local->rx_skb_queue, skb);
 835 }
 836
 837 static ieee80211_rx_result debug_noinline
 838 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
 839 {
 840         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 841         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 842
 843         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 844         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 845                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
 846                              rx->sta->last_seq_ctrl[rx->seqno_idx] ==
 847                              hdr->seq_ctrl)) {
 848                         if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
 849                                 rx->local->dot11FrameDuplicateCount++;
 850                                 rx->sta->num_duplicates++;
 851                         }
 852                         return RX_DROP_UNUSABLE;
 853                 } else
 854                         rx->sta->last_seq_ctrl[rx->seqno_idx] = hdr->seq_ctrl;
 855         }
 856
 857         if (unlikely(rx->skb->len < 16)) {
 858                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 859                 return RX_DROP_MONITOR;
 860         }
 861
 862         /* Drop disallowed frame classes based on STA auth/assoc state;
 863          * IEEE 802.11, Chap 5.5.
 864          *
 865          * mac80211 filters only based on association state, i.e. it drops
 866          * Class 3 frames from not associated stations. hostapd sends
 867          * deauth/disassoc frames when needed. In addition, hostapd is
 868          * responsible for filtering on both auth and assoc states.
 869          */
 870
 871         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
 872                 return ieee80211_rx_mesh_check(rx);
 873
 874         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
 875                       ieee80211_is_pspoll(hdr->frame_control)) &&
 876                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
 877                      rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
 878                      (!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_ASSOC)))) {
 879                 /*
 880                  * accept port control frames from the AP even when it's not
 881                  * yet marked ASSOC to prevent a race where we don't set the
 882                  * assoc bit quickly enough before it sends the first frame
 883                  */
 884                 if (rx->sta && rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
 885                     ieee80211_is_data_present(hdr->frame_control)) {
 886                         u16 ethertype;
 887                         u8 *payload;
 888
 889                         payload = rx->skb->data +
 890                                 ieee80211_hdrlen(hdr->frame_control);
 891                         ethertype = (payload[6] << 8) | payload[7];
 892                         if (cpu_to_be16(ethertype) ==
 893                             rx->sdata->control_port_protocol)
 894                                 return RX_CONTINUE;
 895                 }
 896
 897                 if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
 898                     cfg80211_rx_spurious_frame(rx->sdata->dev,
 899                                                hdr->addr2,
 900                                                GFP_ATOMIC))
 901                         return RX_DROP_UNUSABLE;
 902
 903                 return RX_DROP_MONITOR;
 904         }
 905
 906         return RX_CONTINUE;
 907 }
 908
 909
 910 static ieee80211_rx_result debug_noinline
 911 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
 912 {
 913         struct sk_buff *skb = rx->skb;
 914         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 915         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 916         int keyidx;
 917         int hdrlen;
 918         ieee80211_rx_result result = RX_DROP_UNUSABLE;
 919         struct ieee80211_key *sta_ptk = NULL;
 920         int mmie_keyidx = -1;
 921         __le16 fc;
 922
 923         /*
 924          * Key selection 101
 925          *
 926          * There are four types of keys:
 927          *  - GTK (group keys)
 928          *  - IGTK (group keys for management frames)
 929          *  - PTK (pairwise keys)
 930          *  - STK (station-to-station pairwise keys)
 931          *
 932          * When selecting a key, we have to distinguish between multicast
 933          * (including broadcast) and unicast frames, the latter can only
 934          * use PTKs and STKs while the former always use GTKs and IGTKs.
 935          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
 936          * unicast frames can also use key indices like GTKs. Hence, if we
 937          * don't have a PTK/STK we check the key index for a WEP key.
 938          *
 939          * Note that in a regular BSS, multicast frames are sent by the
 940          * AP only, associated stations unicast the frame to the AP first
 941          * which then multicasts it on their behalf.
 942          *
 943          * There is also a slight problem in IBSS mode: GTKs are negotiated
 944          * with each station, that is something we don't currently handle.
 945          * The spec seems to expect that one negotiates the same key with
 946          * every station but there's no such requirement; VLANs could be
 947          * possible.
 948          */
 949
 950         /*
 951          * No point in finding a key and decrypting if the frame is neither
 952          * addressed to us nor a multicast frame.
 953          */
 954         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
 955                 return RX_CONTINUE;
 956
 957         /* start without a key */
 958         rx->key = NULL;
 959
 960         if (rx->sta)
 961                 sta_ptk = rcu_dereference(rx->sta->ptk);
 962
 963         fc = hdr->frame_control;
 964
 965         if (!ieee80211_has_protected(fc))
 966                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
 967
 968         if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
 969                 rx->key = sta_ptk;
 970                 if ((status->flag & RX_FLAG_DECRYPTED) &&
 971                     (status->flag & RX_FLAG_IV_STRIPPED))
 972                         return RX_CONTINUE;
 973                 /* Skip decryption if the frame is not protected. */
 974                 if (!ieee80211_has_protected(fc))
 975                         return RX_CONTINUE;
 976         } else if (mmie_keyidx >= 0) {
 977                 /* Broadcast/multicast robust management frame / BIP */
 978                 if ((status->flag & RX_FLAG_DECRYPTED) &&
 979                     (status->flag & RX_FLAG_IV_STRIPPED))
 980                         return RX_CONTINUE;
 981
 982                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
 983                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
 984                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
 985                 if (rx->sta)
 986                         rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
 987                 if (!rx->key)
 988                         rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
 989         } else if (!ieee80211_has_protected(fc)) {
 990                 /*
 991                  * The frame was not protected, so skip decryption. However, we
 992                  * need to set rx->key if there is a key that could have been
 993                  * used so that the frame may be dropped if encryption would
 994                  * have been expected.
 995                  */
 996                 struct ieee80211_key *key = NULL;
 997                 struct ieee80211_sub_if_data *sdata = rx->sdata;
 998                 int i;
 999
1000                 if (ieee80211_is_mgmt(fc) &&
1001                     is_multicast_ether_addr(hdr->addr1) &&
1002                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
1003                         rx->key = key;
1004                 else {
1005                         if (rx->sta) {
1006                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1007                                         key = rcu_dereference(rx->sta->gtk[i]);
1008                                         if (key)
1009                                                 break;
1010                                 }
1011                         }
1012                         if (!key) {
1013                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1014                                         key = rcu_dereference(sdata->keys[i]);
1015                                         if (key)
1016                                                 break;
1017                                 }
1018                         }
1019                         if (key)
1020                                 rx->key = key;
1021                 }
1022                 return RX_CONTINUE;
1023         } else {
1024                 u8 keyid;
1025                 /*
1026                  * The device doesn't give us the IV so we won't be
1027                  * able to look up the key. That's ok though, we
1028                  * don't need to decrypt the frame, we just won't
1029                  * be able to keep statistics accurate.
1030                  * Except for key threshold notifications, should
1031                  * we somehow allow the driver to tell us which key
1032                  * the hardware used if this flag is set?
1033                  */
1034                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1035                     (status->flag & RX_FLAG_IV_STRIPPED))
1036                         return RX_CONTINUE;
1037
1038                 hdrlen = ieee80211_hdrlen(fc);
1039
1040                 if (rx->skb->len < 8 + hdrlen)
1041                         return RX_DROP_UNUSABLE; /* TODO: count this? */
1042
1043                 /*
1044                  * no need to call ieee80211_wep_get_keyidx,
1045                  * it verifies a bunch of things we've done already
1046                  */
1047                 skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
1048                 keyidx = keyid >> 6;
1049
1050                 /* check per-station GTK first, if multicast packet */
1051                 if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
1052                         rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
1053
1054                 /* if not found, try default key */
1055                 if (!rx->key) {
1056                         rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
1057
1058                         /*
1059                          * RSNA-protected unicast frames should always be
1060                          * sent with pairwise or station-to-station keys,
1061                          * but for WEP we allow using a key index as well.
1062                          */
1063                         if (rx->key &&
1064                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1065                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1066                             !is_multicast_ether_addr(hdr->addr1))
1067                                 rx->key = NULL;
1068                 }
1069         }
1070
1071         if (rx->key) {
1072                 if (unlikely(rx->key->flags & KEY_FLAG_TAINTED))
1073                         return RX_DROP_MONITOR;
1074
1075                 rx->key->tx_rx_count++;
1076                 /* TODO: add threshold stuff again */
1077         } else {
1078                 return RX_DROP_MONITOR;
1079         }
1080
1081         switch (rx->key->conf.cipher) {
1082         case WLAN_CIPHER_SUITE_WEP40:
1083         case WLAN_CIPHER_SUITE_WEP104:
1084                 result = ieee80211_crypto_wep_decrypt(rx);
1085                 break;
1086         case WLAN_CIPHER_SUITE_TKIP:
1087                 result = ieee80211_crypto_tkip_decrypt(rx);
1088                 break;
1089         case WLAN_CIPHER_SUITE_CCMP:
1090                 result = ieee80211_crypto_ccmp_decrypt(rx);
1091                 break;
1092         case WLAN_CIPHER_SUITE_AES_CMAC:
1093                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
1094                 break;
1095         default:
1096                 /*
1097                  * We can reach here only with HW-only algorithms
1098                  * but why didn't it decrypt the frame?!
1099                  */
1100                 return RX_DROP_UNUSABLE;
1101         }
1102
1103         /* the hdr variable is invalid after the decrypt handlers */
1104
1105         /* either the frame has been decrypted or will be dropped */
1106         status->flag |= RX_FLAG_DECRYPTED;
1107
1108         return result;
1109 }
1110
1111 static ieee80211_rx_result debug_noinline
1112 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1113 {
1114         struct ieee80211_local *local;
1115         struct ieee80211_hdr *hdr;
1116         struct sk_buff *skb;
1117
1118         local = rx->local;
1119         skb = rx->skb;
1120         hdr = (struct ieee80211_hdr *) skb->data;
1121
1122         if (!local->pspolling)
1123                 return RX_CONTINUE;
1124
1125         if (!ieee80211_has_fromds(hdr->frame_control))
1126                 /* this is not from AP */
1127                 return RX_CONTINUE;
1128
1129         if (!ieee80211_is_data(hdr->frame_control))
1130                 return RX_CONTINUE;
1131
1132         if (!ieee80211_has_moredata(hdr->frame_control)) {
1133                 /* AP has no more frames buffered for us */
1134                 local->pspolling = false;
1135                 return RX_CONTINUE;
1136         }
1137
1138         /* more data bit is set, let's request a new frame from the AP */
1139         ieee80211_send_pspoll(local, rx->sdata);
1140
1141         return RX_CONTINUE;
1142 }
1143
1144 static void sta_ps_start(struct sta_info *sta)
1145 {
1146         struct ieee80211_sub_if_data *sdata = sta->sdata;
1147         struct ieee80211_local *local = sdata->local;
1148         struct ps_data *ps;
1149
1150         if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
1151             sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1152                 ps = &sdata->bss->ps;
1153         else
1154                 return;
1155
1156         atomic_inc(&ps->num_sta_ps);
1157         set_sta_flag(sta, WLAN_STA_PS_STA);
1158         if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
1159                 drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1160         ps_dbg(sdata, "STA %pM aid %d enters power save mode\n",
1161                sta->sta.addr, sta->sta.aid);
1162 }
1163
1164 static void sta_ps_end(struct sta_info *sta)
1165 {
1166         ps_dbg(sta->sdata, "STA %pM aid %d exits power save mode\n",
1167                sta->sta.addr, sta->sta.aid);
1168
1169         if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) {
1170                 ps_dbg(sta->sdata, "STA %pM aid %d driver-ps-blocked\n",
1171                        sta->sta.addr, sta->sta.aid);
1172                 return;
1173         }
1174
1175         ieee80211_sta_ps_deliver_wakeup(sta);
1176 }
1177
1178 int ieee80211_sta_ps_transition(struct ieee80211_sta *sta, bool start)
1179 {
1180         struct sta_info *sta_inf = container_of(sta, struct sta_info, sta);
1181         bool in_ps;
1182
1183         WARN_ON(!(sta_inf->local->hw.flags & IEEE80211_HW_AP_LINK_PS));
1184
1185         /* Don't let the same PS state be set twice */
1186         in_ps = test_sta_flag(sta_inf, WLAN_STA_PS_STA);
1187         if ((start && in_ps) || (!start && !in_ps))
1188                 return -EINVAL;
1189
1190         if (start)
1191                 sta_ps_start(sta_inf);
1192         else
1193                 sta_ps_end(sta_inf);
1194
1195         return 0;
1196 }
1197 EXPORT_SYMBOL(ieee80211_sta_ps_transition);
1198
1199 static ieee80211_rx_result debug_noinline
1200 ieee80211_rx_h_uapsd_and_pspoll(struct ieee80211_rx_data *rx)
1201 {
1202         struct ieee80211_sub_if_data *sdata = rx->sdata;
1203         struct ieee80211_hdr *hdr = (void *)rx->skb->data;
1204         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1205         int tid, ac;
1206
1207         if (!rx->sta || !(status->rx_flags & IEEE80211_RX_RA_MATCH))
1208                 return RX_CONTINUE;
1209
1210         if (sdata->vif.type != NL80211_IFTYPE_AP &&
1211             sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
1212                 return RX_CONTINUE;
1213
1214         /*
1215          * The device handles station powersave, so don't do anything about
1216          * uAPSD and PS-Poll frames (the latter shouldn't even come up from
1217          * it to mac80211 since they're handled.)
1218          */
1219         if (sdata->local->hw.flags & IEEE80211_HW_AP_LINK_PS)
1220                 return RX_CONTINUE;
1221
1222         /*
1223          * Don't do anything if the station isn't already asleep. In
1224          * the uAPSD case, the station will probably be marked asleep,
1225          * in the PS-Poll case the station must be confused ...
1226          */
1227         if (!test_sta_flag(rx->sta, WLAN_STA_PS_STA))
1228                 return RX_CONTINUE;
1229
1230         if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) {
1231                 if (!test_sta_flag(rx->sta, WLAN_STA_SP)) {
1232                         if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1233                                 ieee80211_sta_ps_deliver_poll_response(rx->sta);
1234                         else
1235                                 set_sta_flag(rx->sta, WLAN_STA_PSPOLL);
1236                 }
1237
1238                 /* Free PS Poll skb here instead of returning RX_DROP that would
1239                  * count as an dropped frame. */
1240                 dev_kfree_skb(rx->skb);
1241
1242                 return RX_QUEUED;
1243         } else if (!ieee80211_has_morefrags(hdr->frame_control) &&
1244                    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1245                    ieee80211_has_pm(hdr->frame_control) &&
1246                    (ieee80211_is_data_qos(hdr->frame_control) ||
1247                     ieee80211_is_qos_nullfunc(hdr->frame_control))) {
1248                 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
1249                 ac = ieee802_1d_to_ac[tid & 7];
1250
1251                 /*
1252                  * If this AC is not trigger-enabled do nothing.
1253                  *
1254                  * NB: This could/should check a separate bitmap of trigger-
1255                  * enabled queues, but for now we only implement uAPSD w/o
1256                  * TSPEC changes to the ACs, so they're always the same.
1257                  */
1258                 if (!(rx->sta->sta.uapsd_queues & BIT(ac)))
1259                         return RX_CONTINUE;
1260
1261                 /* if we are in a service period, do nothing */
1262                 if (test_sta_flag(rx->sta, WLAN_STA_SP))
1263                         return RX_CONTINUE;
1264
1265                 if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1266                         ieee80211_sta_ps_deliver_uapsd(rx->sta);
1267                 else
1268                         set_sta_flag(rx->sta, WLAN_STA_UAPSD);
1269         }
1270
1271         return RX_CONTINUE;
1272 }
1273
1274 static ieee80211_rx_result debug_noinline
1275 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1276 {
1277         struct sta_info *sta = rx->sta;
1278         struct sk_buff *skb = rx->skb;
1279         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1280         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1281
1282         if (!sta)
1283                 return RX_CONTINUE;
1284
1285         /*
1286          * Update last_rx only for IBSS packets which are for the current
1287          * BSSID to avoid keeping the current IBSS network alive in cases
1288          * where other STAs start using different BSSID.
1289          */
1290         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1291                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1292                                                 NL80211_IFTYPE_ADHOC);
1293                 if (ether_addr_equal(bssid, rx->sdata->u.ibss.bssid)) {
1294                         sta->last_rx = jiffies;
1295                         if (ieee80211_is_data(hdr->frame_control)) {
1296                                 sta->last_rx_rate_idx = status->rate_idx;
1297                                 sta->last_rx_rate_flag = status->flag;
1298                         }
1299                 }
1300         } else if (!is_multicast_ether_addr(hdr->addr1)) {
1301                 /*
1302                  * Mesh beacons will update last_rx when if they are found to
1303                  * match the current local configuration when processed.
1304                  */
1305                 sta->last_rx = jiffies;
1306                 if (ieee80211_is_data(hdr->frame_control)) {
1307                         sta->last_rx_rate_idx = status->rate_idx;
1308                         sta->last_rx_rate_flag = status->flag;
1309                 }
1310         }
1311
1312         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1313                 return RX_CONTINUE;
1314
1315         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1316                 ieee80211_sta_rx_notify(rx->sdata, hdr);
1317
1318         sta->rx_fragments++;
1319         sta->rx_bytes += rx->skb->len;
1320         if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
1321                 sta->last_signal = status->signal;
1322                 ewma_add(&sta->avg_signal, -status->signal);
1323         }
1324
1325         /*
1326          * Change STA power saving mode only at the end of a frame
1327          * exchange sequence.
1328          */
1329         if (!(sta->local->hw.flags & IEEE80211_HW_AP_LINK_PS) &&
1330             !ieee80211_has_morefrags(hdr->frame_control) &&
1331             !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1332             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1333              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1334                 if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
1335                         /*
1336                          * Ignore doze->wake transitions that are
1337                          * indicated by non-data frames, the standard
1338                          * is unclear here, but for example going to
1339                          * PS mode and then scanning would cause a
1340                          * doze->wake transition for the probe request,
1341                          * and that is clearly undesirable.
1342                          */
1343                         if (ieee80211_is_data(hdr->frame_control) &&
1344                             !ieee80211_has_pm(hdr->frame_control))
1345                                 sta_ps_end(sta);
1346                 } else {
1347                         if (ieee80211_has_pm(hdr->frame_control))
1348                                 sta_ps_start(sta);
1349                 }
1350         }
1351
1352         /*
1353          * Drop (qos-)data::nullfunc frames silently, since they
1354          * are used only to control station power saving mode.
1355          */
1356         if (ieee80211_is_nullfunc(hdr->frame_control) ||
1357             ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1358                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1359
1360                 /*
1361                  * If we receive a 4-addr nullfunc frame from a STA
1362                  * that was not moved to a 4-addr STA vlan yet send
1363                  * the event to userspace and for older hostapd drop
1364                  * the frame to the monitor interface.
1365                  */
1366                 if (ieee80211_has_a4(hdr->frame_control) &&
1367                     (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1368                      (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1369                       !rx->sdata->u.vlan.sta))) {
1370                         if (!test_and_set_sta_flag(sta, WLAN_STA_4ADDR_EVENT))
1371                                 cfg80211_rx_unexpected_4addr_frame(
1372                                         rx->sdata->dev, sta->sta.addr,
1373                                         GFP_ATOMIC);
1374                         return RX_DROP_MONITOR;
1375                 }
1376                 /*
1377                  * Update counter and free packet here to avoid
1378                  * counting this as a dropped packed.
1379                  */
1380                 sta->rx_packets++;
1381                 dev_kfree_skb(rx->skb);
1382                 return RX_QUEUED;
1383         }
1384
1385         return RX_CONTINUE;
1386 } /* ieee80211_rx_h_sta_process */
1387
1388 static inline struct ieee80211_fragment_entry *
1389 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1390                          unsigned int frag, unsigned int seq, int rx_queue,
1391                          struct sk_buff **skb)
1392 {
1393         struct ieee80211_fragment_entry *entry;
1394
1395         entry = &sdata->fragments[sdata->fragment_next++];
1396         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1397                 sdata->fragment_next = 0;
1398
1399         if (!skb_queue_empty(&entry->skb_list))
1400                 __skb_queue_purge(&entry->skb_list);
1401
1402         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1403         *skb = NULL;
1404         entry->first_frag_time = jiffies;
1405         entry->seq = seq;
1406         entry->rx_queue = rx_queue;
1407         entry->last_frag = frag;
1408         entry->ccmp = 0;
1409         entry->extra_len = 0;
1410
1411         return entry;
1412 }
1413
1414 static inline struct ieee80211_fragment_entry *
1415 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1416                           unsigned int frag, unsigned int seq,
1417                           int rx_queue, struct ieee80211_hdr *hdr)
1418 {
1419         struct ieee80211_fragment_entry *entry;
1420         int i, idx;
1421
1422         idx = sdata->fragment_next;
1423         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1424                 struct ieee80211_hdr *f_hdr;
1425
1426                 idx--;
1427                 if (idx < 0)
1428                         idx = IEEE80211_FRAGMENT_MAX - 1;
1429
1430                 entry = &sdata->fragments[idx];
1431                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1432                     entry->rx_queue != rx_queue ||
1433                     entry->last_frag + 1 != frag)
1434                         continue;
1435
1436                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1437
1438                 /*
1439                  * Check ftype and addresses are equal, else check next fragment
1440                  */
1441                 if (((hdr->frame_control ^ f_hdr->frame_control) &
1442                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1443                     !ether_addr_equal(hdr->addr1, f_hdr->addr1) ||
1444                     !ether_addr_equal(hdr->addr2, f_hdr->addr2))
1445                         continue;
1446
1447                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1448                         __skb_queue_purge(&entry->skb_list);
1449                         continue;
1450                 }
1451                 return entry;
1452         }
1453
1454         return NULL;
1455 }
1456
1457 static ieee80211_rx_result debug_noinline
1458 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1459 {
1460         struct ieee80211_hdr *hdr;
1461         u16 sc;
1462         __le16 fc;
1463         unsigned int frag, seq;
1464         struct ieee80211_fragment_entry *entry;
1465         struct sk_buff *skb;
1466         struct ieee80211_rx_status *status;
1467
1468         hdr = (struct ieee80211_hdr *)rx->skb->data;
1469         fc = hdr->frame_control;
1470         sc = le16_to_cpu(hdr->seq_ctrl);
1471         frag = sc & IEEE80211_SCTL_FRAG;
1472
1473         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1474                    (rx->skb)->len < 24 ||
1475                    is_multicast_ether_addr(hdr->addr1))) {
1476                 /* not fragmented */
1477                 goto out;
1478         }
1479         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1480
1481         if (skb_linearize(rx->skb))
1482                 return RX_DROP_UNUSABLE;
1483
1484         /*
1485          *  skb_linearize() might change the skb->data and
1486          *  previously cached variables (in this case, hdr) need to
1487          *  be refreshed with the new data.
1488          */
1489         hdr = (struct ieee80211_hdr *)rx->skb->data;
1490         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1491
1492         if (frag == 0) {
1493                 /* This is the first fragment of a new frame. */
1494                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1495                                                  rx->seqno_idx, &(rx->skb));
1496                 if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP &&
1497                     ieee80211_has_protected(fc)) {
1498                         int queue = rx->security_idx;
1499                         /* Store CCMP PN so that we can verify that the next
1500                          * fragment has a sequential PN value. */
1501                         entry->ccmp = 1;
1502                         memcpy(entry->last_pn,
1503                                rx->key->u.ccmp.rx_pn[queue],
1504                                CCMP_PN_LEN);
1505                 }
1506                 return RX_QUEUED;
1507         }
1508
1509         /* This is a fragment for a frame that should already be pending in
1510          * fragment cache. Add this fragment to the end of the pending entry.
1511          */
1512         entry = ieee80211_reassemble_find(rx->sdata, frag, seq,
1513                                           rx->seqno_idx, hdr);
1514         if (!entry) {
1515                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1516                 return RX_DROP_MONITOR;
1517         }
1518
1519         /* Verify that MPDUs within one MSDU have sequential PN values.
1520          * (IEEE 802.11i, 8.3.3.4.5) */
1521         if (entry->ccmp) {
1522                 int i;
1523                 u8 pn[CCMP_PN_LEN], *rpn;
1524                 int queue;
1525                 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP)
1526                         return RX_DROP_UNUSABLE;
1527                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1528                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1529                         pn[i]++;
1530                         if (pn[i])
1531                                 break;
1532                 }
1533                 queue = rx->security_idx;
1534                 rpn = rx->key->u.ccmp.rx_pn[queue];
1535                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1536                         return RX_DROP_UNUSABLE;
1537                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1538         }
1539
1540         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1541         __skb_queue_tail(&entry->skb_list, rx->skb);
1542         entry->last_frag = frag;
1543         entry->extra_len += rx->skb->len;
1544         if (ieee80211_has_morefrags(fc)) {
1545                 rx->skb = NULL;
1546                 return RX_QUEUED;
1547         }
1548
1549         rx->skb = __skb_dequeue(&entry->skb_list);
1550         if (skb_tailroom(rx->skb) < entry->extra_len) {
1551                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1552                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1553                                               GFP_ATOMIC))) {
1554                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1555                         __skb_queue_purge(&entry->skb_list);
1556                         return RX_DROP_UNUSABLE;
1557                 }
1558         }
1559         while ((skb = __skb_dequeue(&entry->skb_list))) {
1560                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1561                 dev_kfree_skb(skb);
1562         }
1563
1564         /* Complete frame has been reassembled - process it now */
1565         status = IEEE80211_SKB_RXCB(rx->skb);
1566         status->rx_flags |= IEEE80211_RX_FRAGMENTED;
1567
1568  out:
1569         if (rx->sta)
1570                 rx->sta->rx_packets++;
1571         if (is_multicast_ether_addr(hdr->addr1))
1572                 rx->local->dot11MulticastReceivedFrameCount++;
1573         else
1574                 ieee80211_led_rx(rx->local);
1575         return RX_CONTINUE;
1576 }
1577
1578 static int
1579 ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1580 {
1581         if (unlikely(!rx->sta ||
1582             !test_sta_flag(rx->sta, WLAN_STA_AUTHORIZED)))
1583                 return -EACCES;
1584
1585         return 0;
1586 }
1587
1588 static int
1589 ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1590 {
1591         struct sk_buff *skb = rx->skb;
1592         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1593
1594         /*
1595          * Pass through unencrypted frames if the hardware has
1596          * decrypted them already.
1597          */
1598         if (status->flag & RX_FLAG_DECRYPTED)
1599                 return 0;
1600
1601         /* Drop unencrypted frames if key is set. */
1602         if (unlikely(!ieee80211_has_protected(fc) &&
1603                      !ieee80211_is_nullfunc(fc) &&
1604                      ieee80211_is_data(fc) &&
1605                      (rx->key || rx->sdata->drop_unencrypted)))
1606                 return -EACCES;
1607
1608         return 0;
1609 }
1610
1611 static int
1612 ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1613 {
1614         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1615         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1616         __le16 fc = hdr->frame_control;
1617
1618         /*
1619          * Pass through unencrypted frames if the hardware has
1620          * decrypted them already.
1621          */
1622         if (status->flag & RX_FLAG_DECRYPTED)
1623                 return 0;
1624
1625         if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) {
1626                 if (unlikely(!ieee80211_has_protected(fc) &&
1627                              ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1628                              rx->key)) {
1629                         if (ieee80211_is_deauth(fc))
1630                                 cfg80211_send_unprot_deauth(rx->sdata->dev,
1631                                                             rx->skb->data,
1632                                                             rx->skb->len);
1633                         else if (ieee80211_is_disassoc(fc))
1634                                 cfg80211_send_unprot_disassoc(rx->sdata->dev,
1635                                                               rx->skb->data,
1636                                                               rx->skb->len);
1637                         return -EACCES;
1638                 }
1639                 /* BIP does not use Protected field, so need to check MMIE */
1640                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1641                              ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
1642                         if (ieee80211_is_deauth(fc))
1643                                 cfg80211_send_unprot_deauth(rx->sdata->dev,
1644                                                             rx->skb->data,
1645                                                             rx->skb->len);
1646                         else if (ieee80211_is_disassoc(fc))
1647                                 cfg80211_send_unprot_disassoc(rx->sdata->dev,
1648                                                               rx->skb->data,
1649                                                               rx->skb->len);
1650                         return -EACCES;
1651                 }
1652                 /*
1653                  * When using MFP, Action frames are not allowed prior to
1654                  * having configured keys.
1655                  */
1656                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1657                              ieee80211_is_robust_mgmt_frame(
1658                                      (struct ieee80211_hdr *) rx->skb->data)))
1659                         return -EACCES;
1660         }
1661
1662         return 0;
1663 }
1664
1665 static int
1666 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx, bool *port_control)
1667 {
1668         struct ieee80211_sub_if_data *sdata = rx->sdata;
1669         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1670         bool check_port_control = false;
1671         struct ethhdr *ehdr;
1672         int ret;
1673
1674         *port_control = false;
1675         if (ieee80211_has_a4(hdr->frame_control) &&
1676             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1677                 return -1;
1678
1679         if (sdata->vif.type == NL80211_IFTYPE_STATION &&
1680             !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) {
1681
1682                 if (!sdata->u.mgd.use_4addr)
1683                         return -1;
1684                 else
1685                         check_port_control = true;
1686         }
1687
1688         if (is_multicast_ether_addr(hdr->addr1) &&
1689             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta)
1690                 return -1;
1691
1692         ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1693         if (ret < 0)
1694                 return ret;
1695
1696         ehdr = (struct ethhdr *) rx->skb->data;
1697         if (ehdr->h_proto == rx->sdata->control_port_protocol)
1698                 *port_control = true;
1699         else if (check_port_control)
1700                 return -1;
1701
1702         return 0;
1703 }
1704
1705 /*
1706  * requires that rx->skb is a frame with ethernet header
1707  */
1708 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1709 {
1710         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1711                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1712         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1713
1714         /*
1715          * Allow EAPOL frames to us/the PAE group address regardless
1716          * of whether the frame was encrypted or not.
1717          */
1718         if (ehdr->h_proto == rx->sdata->control_port_protocol &&
1719             (ether_addr_equal(ehdr->h_dest, rx->sdata->vif.addr) ||
1720              ether_addr_equal(ehdr->h_dest, pae_group_addr)))
1721                 return true;
1722
1723         if (ieee80211_802_1x_port_control(rx) ||
1724             ieee80211_drop_unencrypted(rx, fc))
1725                 return false;
1726
1727         return true;
1728 }
1729
1730 /*
1731  * requires that rx->skb is a frame with ethernet header
1732  */
1733 static void
1734 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1735 {
1736         struct ieee80211_sub_if_data *sdata = rx->sdata;
1737         struct net_device *dev = sdata->dev;
1738         struct sk_buff *skb, *xmit_skb;
1739         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1740         struct sta_info *dsta;
1741         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1742
1743         skb = rx->skb;
1744         xmit_skb = NULL;
1745
1746         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1747              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1748             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1749             (status->rx_flags & IEEE80211_RX_RA_MATCH) &&
1750             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1751                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1752                         /*
1753                          * send multicast frames both to higher layers in
1754                          * local net stack and back to the wireless medium
1755                          */
1756                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1757                         if (!xmit_skb)
1758                                 net_info_ratelimited("%s: failed to clone multicast frame\n",
1759                                                     dev->name);
1760                 } else {
1761                         dsta = sta_info_get(sdata, skb->data);
1762                         if (dsta) {
1763                                 /*
1764                                  * The destination station is associated to
1765                                  * this AP (in this VLAN), so send the frame
1766                                  * directly to it and do not pass it to local
1767                                  * net stack.
1768                                  */
1769                                 xmit_skb = skb;
1770                                 skb = NULL;
1771                         }
1772                 }
1773         }
1774
1775         if (skb) {
1776                 int align __maybe_unused;
1777
1778 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1779                 /*
1780                  * 'align' will only take the values 0 or 2 here
1781                  * since all frames are required to be aligned
1782                  * to 2-byte boundaries when being passed to
1783                  * mac80211. That also explains the __skb_push()
1784                  * below.
1785                  */
1786                 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1787                 if (align) {
1788                         if (WARN_ON(skb_headroom(skb) < 3)) {
1789                                 dev_kfree_skb(skb);
1790                                 skb = NULL;
1791                         } else {
1792                                 u8 *data = skb->data;
1793                                 size_t len = skb_headlen(skb);
1794                                 skb->data -= align;
1795                                 memmove(skb->data, data, len);
1796                                 skb_set_tail_pointer(skb, len);
1797                         }
1798                 }
1799 #endif
1800
1801                 if (skb) {
1802                         /* deliver to local stack */
1803                         skb->protocol = eth_type_trans(skb, dev);
1804                         memset(skb->cb, 0, sizeof(skb->cb));
1805                         netif_receive_skb(skb);
1806                 }
1807         }
1808
1809         if (xmit_skb) {
1810                 /*
1811                  * Send to wireless media and increase priority by 256 to
1812                  * keep the received priority instead of reclassifying
1813                  * the frame (see cfg80211_classify8021d).
1814                  */
1815                 xmit_skb->priority += 256;
1816                 xmit_skb->protocol = htons(ETH_P_802_3);
1817                 skb_reset_network_header(xmit_skb);
1818                 skb_reset_mac_header(xmit_skb);
1819                 dev_queue_xmit(xmit_skb);
1820         }
1821 }
1822
1823 static ieee80211_rx_result debug_noinline
1824 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1825 {
1826         struct net_device *dev = rx->sdata->dev;
1827         struct sk_buff *skb = rx->skb;
1828         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1829         __le16 fc = hdr->frame_control;
1830         struct sk_buff_head frame_list;
1831         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1832
1833         if (unlikely(!ieee80211_is_data(fc)))
1834                 return RX_CONTINUE;
1835
1836         if (unlikely(!ieee80211_is_data_present(fc)))
1837                 return RX_DROP_MONITOR;
1838
1839         if (!(status->rx_flags & IEEE80211_RX_AMSDU))
1840                 return RX_CONTINUE;
1841
1842         if (ieee80211_has_a4(hdr->frame_control) &&
1843             rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1844             !rx->sdata->u.vlan.sta)
1845                 return RX_DROP_UNUSABLE;
1846
1847         if (is_multicast_ether_addr(hdr->addr1) &&
1848             ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1849               rx->sdata->u.vlan.sta) ||
1850              (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1851               rx->sdata->u.mgd.use_4addr)))
1852                 return RX_DROP_UNUSABLE;
1853
1854         skb->dev = dev;
1855         __skb_queue_head_init(&frame_list);
1856
1857         if (skb_linearize(skb))
1858                 return RX_DROP_UNUSABLE;
1859
1860         ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1861                                  rx->sdata->vif.type,
1862                                  rx->local->hw.extra_tx_headroom, true);
1863
1864         while (!skb_queue_empty(&frame_list)) {
1865                 rx->skb = __skb_dequeue(&frame_list);
1866
1867                 if (!ieee80211_frame_allowed(rx, fc)) {
1868                         dev_kfree_skb(rx->skb);
1869                         continue;
1870                 }
1871                 dev->stats.rx_packets++;
1872                 dev->stats.rx_bytes += rx->skb->len;
1873
1874                 ieee80211_deliver_skb(rx);
1875         }
1876
1877         return RX_QUEUED;
1878 }
1879
1880 #ifdef CONFIG_MAC80211_MESH
1881 static ieee80211_rx_result
1882 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1883 {
1884         struct ieee80211_hdr *fwd_hdr, *hdr;
1885         struct ieee80211_tx_info *info;
1886         struct ieee80211s_hdr *mesh_hdr;
1887         struct sk_buff *skb = rx->skb, *fwd_skb;
1888         struct ieee80211_local *local = rx->local;
1889         struct ieee80211_sub_if_data *sdata = rx->sdata;
1890         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1891         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1892         __le16 reason = cpu_to_le16(WLAN_REASON_MESH_PATH_NOFORWARD);
1893         u16 q, hdrlen;
1894
1895         hdr = (struct ieee80211_hdr *) skb->data;
1896         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1897         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
1898
1899         /* frame is in RMC, don't forward */
1900         if (ieee80211_is_data(hdr->frame_control) &&
1901             is_multicast_ether_addr(hdr->addr1) &&
1902             mesh_rmc_check(hdr->addr3, mesh_hdr, rx->sdata))
1903                 return RX_DROP_MONITOR;
1904
1905         if (!ieee80211_is_data(hdr->frame_control))
1906                 return RX_CONTINUE;
1907
1908         if (!mesh_hdr->ttl)
1909                 return RX_DROP_MONITOR;
1910
1911         if (mesh_hdr->flags & MESH_FLAGS_AE) {
1912                 struct mesh_path *mppath;
1913                 char *proxied_addr;
1914                 char *mpp_addr;
1915
1916                 if (is_multicast_ether_addr(hdr->addr1)) {
1917                         mpp_addr = hdr->addr3;
1918                         proxied_addr = mesh_hdr->eaddr1;
1919                 } else {
1920                         mpp_addr = hdr->addr4;
1921                         proxied_addr = mesh_hdr->eaddr2;
1922                 }
1923
1924                 rcu_read_lock();
1925                 mppath = mpp_path_lookup(proxied_addr, sdata);
1926                 if (!mppath) {
1927                         mpp_path_add(proxied_addr, mpp_addr, sdata);
1928                 } else {
1929                         spin_lock_bh(&mppath->state_lock);
1930                         if (!ether_addr_equal(mppath->mpp, mpp_addr))
1931                                 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
1932                         spin_unlock_bh(&mppath->state_lock);
1933                 }
1934                 rcu_read_unlock();
1935         }
1936
1937         /* Frame has reached destination.  Don't forward */
1938         if (!is_multicast_ether_addr(hdr->addr1) &&
1939             ether_addr_equal(sdata->vif.addr, hdr->addr3))
1940                 return RX_CONTINUE;
1941
1942         q = ieee80211_select_queue_80211(sdata, skb, hdr);
1943         if (ieee80211_queue_stopped(&local->hw, q)) {
1944                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion);
1945                 return RX_DROP_MONITOR;
1946         }
1947         skb_set_queue_mapping(skb, q);
1948
1949         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1950                 goto out;
1951
1952         if (!--mesh_hdr->ttl) {
1953                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
1954                 return RX_DROP_MONITOR;
1955         }
1956
1957         if (!ifmsh->mshcfg.dot11MeshForwarding)
1958                 goto out;
1959
1960         fwd_skb = skb_copy(skb, GFP_ATOMIC);
1961         if (!fwd_skb) {
1962                 net_info_ratelimited("%s: failed to clone mesh frame\n",
1963                                     sdata->name);
1964                 goto out;
1965         }
1966
1967         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
1968         info = IEEE80211_SKB_CB(fwd_skb);
1969         memset(info, 0, sizeof(*info));
1970         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1971         info->control.vif = &rx->sdata->vif;
1972         info->control.jiffies = jiffies;
1973         if (is_multicast_ether_addr(fwd_hdr->addr1)) {
1974                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_mcast);
1975                 memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
1976         } else if (!mesh_nexthop_lookup(fwd_skb, sdata)) {
1977                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_unicast);
1978         } else {
1979                 /* unable to resolve next hop */
1980                 mesh_path_error_tx(ifmsh->mshcfg.element_ttl, fwd_hdr->addr3,
1981                                     0, reason, fwd_hdr->addr2, sdata);
1982                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_no_route);
1983                 kfree_skb(fwd_skb);
1984                 return RX_DROP_MONITOR;
1985         }
1986
1987         IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_frames);
1988         ieee80211_add_pending_skb(local, fwd_skb);
1989  out:
1990         if (is_multicast_ether_addr(hdr->addr1) ||
1991             sdata->dev->flags & IFF_PROMISC)
1992                 return RX_CONTINUE;
1993         else
1994                 return RX_DROP_MONITOR;
1995 }
1996 #endif
1997
1998 static ieee80211_rx_result debug_noinline
1999 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
2000 {
2001         struct ieee80211_sub_if_data *sdata = rx->sdata;
2002         struct ieee80211_local *local = rx->local;
2003         struct net_device *dev = sdata->dev;
2004         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2005         __le16 fc = hdr->frame_control;
2006         bool port_control;
2007         int err;
2008
2009         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
2010                 return RX_CONTINUE;
2011
2012         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
2013                 return RX_DROP_MONITOR;
2014
2015         /*
2016          * Send unexpected-4addr-frame event to hostapd. For older versions,
2017          * also drop the frame to cooked monitor interfaces.
2018          */
2019         if (ieee80211_has_a4(hdr->frame_control) &&
2020             sdata->vif.type == NL80211_IFTYPE_AP) {
2021                 if (rx->sta &&
2022                     !test_and_set_sta_flag(rx->sta, WLAN_STA_4ADDR_EVENT))
2023                         cfg80211_rx_unexpected_4addr_frame(
2024                                 rx->sdata->dev, rx->sta->sta.addr, GFP_ATOMIC);
2025                 return RX_DROP_MONITOR;
2026         }
2027
2028         err = __ieee80211_data_to_8023(rx, &port_control);
2029         if (unlikely(err))
2030                 return RX_DROP_UNUSABLE;
2031
2032         if (!ieee80211_frame_allowed(rx, fc))
2033                 return RX_DROP_MONITOR;
2034
2035         if (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
2036             unlikely(port_control) && sdata->bss) {
2037                 sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
2038                                      u.ap);
2039                 dev = sdata->dev;
2040                 rx->sdata = sdata;
2041         }
2042
2043         rx->skb->dev = dev;
2044
2045         dev->stats.rx_packets++;
2046         dev->stats.rx_bytes += rx->skb->len;
2047
2048         if (local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
2049             !is_multicast_ether_addr(
2050                     ((struct ethhdr *)rx->skb->data)->h_dest) &&
2051             (!local->scanning &&
2052              !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state))) {
2053                         mod_timer(&local->dynamic_ps_timer, jiffies +
2054                          msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
2055         }
2056
2057         ieee80211_deliver_skb(rx);
2058
2059         return RX_QUEUED;
2060 }
2061
2062 static ieee80211_rx_result debug_noinline
2063 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
2064 {
2065         struct sk_buff *skb = rx->skb;
2066         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
2067         struct tid_ampdu_rx *tid_agg_rx;
2068         u16 start_seq_num;
2069         u16 tid;
2070
2071         if (likely(!ieee80211_is_ctl(bar->frame_control)))
2072                 return RX_CONTINUE;
2073
2074         if (ieee80211_is_back_req(bar->frame_control)) {
2075                 struct {
2076                         __le16 control, start_seq_num;
2077                 } __packed bar_data;
2078
2079                 if (!rx->sta)
2080                         return RX_DROP_MONITOR;
2081
2082                 if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
2083                                   &bar_data, sizeof(bar_data)))
2084                         return RX_DROP_MONITOR;
2085
2086                 tid = le16_to_cpu(bar_data.control) >> 12;
2087
2088                 tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
2089                 if (!tid_agg_rx)
2090                         return RX_DROP_MONITOR;
2091
2092                 start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
2093
2094                 /* reset session timer */
2095                 if (tid_agg_rx->timeout)
2096                         mod_timer(&tid_agg_rx->session_timer,
2097                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
2098
2099                 spin_lock(&tid_agg_rx->reorder_lock);
2100                 /* release stored frames up to start of BAR */
2101                 ieee80211_release_reorder_frames(rx->sdata, tid_agg_rx,
2102                                                  start_seq_num);
2103                 spin_unlock(&tid_agg_rx->reorder_lock);
2104
2105                 kfree_skb(skb);
2106                 return RX_QUEUED;
2107         }
2108
2109         /*
2110          * After this point, we only want management frames,
2111          * so we can drop all remaining control frames to
2112          * cooked monitor interfaces.
2113          */
2114         return RX_DROP_MONITOR;
2115 }
2116
2117 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
2118                                            struct ieee80211_mgmt *mgmt,
2119                                            size_t len)
2120 {
2121         struct ieee80211_local *local = sdata->local;
2122         struct sk_buff *skb;
2123         struct ieee80211_mgmt *resp;
2124
2125         if (!ether_addr_equal(mgmt->da, sdata->vif.addr)) {
2126                 /* Not to own unicast address */
2127                 return;
2128         }
2129
2130         if (!ether_addr_equal(mgmt->sa, sdata->u.mgd.bssid) ||
2131             !ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid)) {
2132                 /* Not from the current AP or not associated yet. */
2133                 return;
2134         }
2135
2136         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
2137                 /* Too short SA Query request frame */
2138                 return;
2139         }
2140
2141         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
2142         if (skb == NULL)
2143                 return;
2144
2145         skb_reserve(skb, local->hw.extra_tx_headroom);
2146         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
2147         memset(resp, 0, 24);
2148         memcpy(resp->da, mgmt->sa, ETH_ALEN);
2149         memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
2150         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
2151         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2152                                           IEEE80211_STYPE_ACTION);
2153         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
2154         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
2155         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
2156         memcpy(resp->u.action.u.sa_query.trans_id,
2157                mgmt->u.action.u.sa_query.trans_id,
2158                WLAN_SA_QUERY_TR_ID_LEN);
2159
2160         ieee80211_tx_skb(sdata, skb);
2161 }
2162
2163 static ieee80211_rx_result debug_noinline
2164 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
2165 {
2166         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2167         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2168
2169         /*
2170          * From here on, look only at management frames.
2171          * Data and control frames are already handled,
2172          * and unknown (reserved) frames are useless.
2173          */
2174         if (rx->skb->len < 24)
2175                 return RX_DROP_MONITOR;
2176
2177         if (!ieee80211_is_mgmt(mgmt->frame_control))
2178                 return RX_DROP_MONITOR;
2179
2180         if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
2181             ieee80211_is_beacon(mgmt->frame_control) &&
2182             !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) {
2183                 int sig = 0;
2184
2185                 if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2186                         sig = status->signal;
2187
2188                 cfg80211_report_obss_beacon(rx->local->hw.wiphy,
2189                                             rx->skb->data, rx->skb->len,
2190                                             status->freq, sig, GFP_ATOMIC);
2191                 rx->flags |= IEEE80211_RX_BEACON_REPORTED;
2192         }
2193
2194         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2195                 return RX_DROP_MONITOR;
2196
2197         if (ieee80211_drop_unencrypted_mgmt(rx))
2198                 return RX_DROP_UNUSABLE;
2199
2200         return RX_CONTINUE;
2201 }
2202
2203 static ieee80211_rx_result debug_noinline
2204 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2205 {
2206         struct ieee80211_local *local = rx->local;
2207         struct ieee80211_sub_if_data *sdata = rx->sdata;
2208         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2209         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2210         int len = rx->skb->len;
2211
2212         if (!ieee80211_is_action(mgmt->frame_control))
2213                 return RX_CONTINUE;
2214
2215         /* drop too small frames */
2216         if (len < IEEE80211_MIN_ACTION_SIZE)
2217                 return RX_DROP_UNUSABLE;
2218
2219         if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC)
2220                 return RX_DROP_UNUSABLE;
2221
2222         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2223                 return RX_DROP_UNUSABLE;
2224
2225         switch (mgmt->u.action.category) {
2226         case WLAN_CATEGORY_HT:
2227                 /* reject HT action frames from stations not supporting HT */
2228                 if (!rx->sta->sta.ht_cap.ht_supported)
2229                         goto invalid;
2230
2231                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2232                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2233                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2234                     sdata->vif.type != NL80211_IFTYPE_AP &&
2235                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2236                         break;
2237
2238                 /* verify action & smps_control are present */
2239                 if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2240                         goto invalid;
2241
2242                 switch (mgmt->u.action.u.ht_smps.action) {
2243                 case WLAN_HT_ACTION_SMPS: {
2244                         struct ieee80211_supported_band *sband;
2245                         u8 smps;
2246
2247                         /* convert to HT capability */
2248                         switch (mgmt->u.action.u.ht_smps.smps_control) {
2249                         case WLAN_HT_SMPS_CONTROL_DISABLED:
2250                                 smps = WLAN_HT_CAP_SM_PS_DISABLED;
2251                                 break;
2252                         case WLAN_HT_SMPS_CONTROL_STATIC:
2253                                 smps = WLAN_HT_CAP_SM_PS_STATIC;
2254                                 break;
2255                         case WLAN_HT_SMPS_CONTROL_DYNAMIC:
2256                                 smps = WLAN_HT_CAP_SM_PS_DYNAMIC;
2257                                 break;
2258                         default:
2259                                 goto invalid;
2260                         }
2261                         smps <<= IEEE80211_HT_CAP_SM_PS_SHIFT;
2262
2263                         /* if no change do nothing */
2264                         if ((rx->sta->sta.ht_cap.cap &
2265                                         IEEE80211_HT_CAP_SM_PS) == smps)
2266                                 goto handled;
2267
2268                         rx->sta->sta.ht_cap.cap &= ~IEEE80211_HT_CAP_SM_PS;
2269                         rx->sta->sta.ht_cap.cap |= smps;
2270
2271                         sband = rx->local->hw.wiphy->bands[status->band];
2272
2273                         rate_control_rate_update(local, sband, rx->sta,
2274                                                  IEEE80211_RC_SMPS_CHANGED);
2275                         goto handled;
2276                 }
2277                 default:
2278                         goto invalid;
2279                 }
2280
2281                 break;
2282         case WLAN_CATEGORY_BACK:
2283                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2284                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2285                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2286                     sdata->vif.type != NL80211_IFTYPE_AP &&
2287                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2288                         break;
2289
2290                 /* verify action_code is present */
2291                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2292                         break;
2293
2294                 switch (mgmt->u.action.u.addba_req.action_code) {
2295                 case WLAN_ACTION_ADDBA_REQ:
2296                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2297                                    sizeof(mgmt->u.action.u.addba_req)))
2298                                 goto invalid;
2299                         break;
2300                 case WLAN_ACTION_ADDBA_RESP:
2301                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2302                                    sizeof(mgmt->u.action.u.addba_resp)))
2303                                 goto invalid;
2304                         break;
2305                 case WLAN_ACTION_DELBA:
2306                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2307                                    sizeof(mgmt->u.action.u.delba)))
2308                                 goto invalid;
2309                         break;
2310                 default:
2311                         goto invalid;
2312                 }
2313
2314                 goto queue;
2315         case WLAN_CATEGORY_SPECTRUM_MGMT:
2316                 if (status->band != IEEE80211_BAND_5GHZ)
2317                         break;
2318
2319                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2320                         break;
2321
2322                 /* verify action_code is present */
2323                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2324                         break;
2325
2326                 switch (mgmt->u.action.u.measurement.action_code) {
2327                 case WLAN_ACTION_SPCT_MSR_REQ:
2328                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2329                                    sizeof(mgmt->u.action.u.measurement)))
2330                                 break;
2331                         ieee80211_process_measurement_req(sdata, mgmt, len);
2332                         goto handled;
2333                 case WLAN_ACTION_SPCT_CHL_SWITCH:
2334                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2335                                    sizeof(mgmt->u.action.u.chan_switch)))
2336                                 break;
2337
2338                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2339                                 break;
2340
2341                         if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
2342                                 break;
2343
2344                         goto queue;
2345                 }
2346                 break;
2347         case WLAN_CATEGORY_SA_QUERY:
2348                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2349                            sizeof(mgmt->u.action.u.sa_query)))
2350                         break;
2351
2352                 switch (mgmt->u.action.u.sa_query.action) {
2353                 case WLAN_ACTION_SA_QUERY_REQUEST:
2354                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2355                                 break;
2356                         ieee80211_process_sa_query_req(sdata, mgmt, len);
2357                         goto handled;
2358                 }
2359                 break;
2360         case WLAN_CATEGORY_SELF_PROTECTED:
2361                 switch (mgmt->u.action.u.self_prot.action_code) {
2362                 case WLAN_SP_MESH_PEERING_OPEN:
2363                 case WLAN_SP_MESH_PEERING_CLOSE:
2364                 case WLAN_SP_MESH_PEERING_CONFIRM:
2365                         if (!ieee80211_vif_is_mesh(&sdata->vif))
2366                                 goto invalid;
2367                         if (sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE)
2368                                 /* userspace handles this frame */
2369                                 break;
2370                         goto queue;
2371                 case WLAN_SP_MGK_INFORM:
2372                 case WLAN_SP_MGK_ACK:
2373                         if (!ieee80211_vif_is_mesh(&sdata->vif))
2374                                 goto invalid;
2375                         break;
2376                 }
2377                 break;
2378         case WLAN_CATEGORY_MESH_ACTION:
2379                 if (!ieee80211_vif_is_mesh(&sdata->vif))
2380                         break;
2381                 if (mesh_action_is_path_sel(mgmt) &&
2382                   (!mesh_path_sel_is_hwmp(sdata)))
2383                         break;
2384                 goto queue;
2385         }
2386
2387         return RX_CONTINUE;
2388
2389  invalid:
2390         status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
2391         /* will return in the next handlers */
2392         return RX_CONTINUE;
2393
2394  handled:
2395         if (rx->sta)
2396                 rx->sta->rx_packets++;
2397         dev_kfree_skb(rx->skb);
2398         return RX_QUEUED;
2399
2400  queue:
2401         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2402         skb_queue_tail(&sdata->skb_queue, rx->skb);
2403         ieee80211_queue_work(&local->hw, &sdata->work);
2404         if (rx->sta)
2405                 rx->sta->rx_packets++;
2406         return RX_QUEUED;
2407 }
2408
2409 static ieee80211_rx_result debug_noinline
2410 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
2411 {
2412         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2413         int sig = 0;
2414
2415         /* skip known-bad action frames and return them in the next handler */
2416         if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
2417                 return RX_CONTINUE;
2418
2419         /*
2420          * Getting here means the kernel doesn't know how to handle
2421          * it, but maybe userspace does ... include returned frames
2422          * so userspace can register for those to know whether ones
2423          * it transmitted were processed or returned.
2424          */
2425
2426         if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2427                 sig = status->signal;
2428
2429         if (cfg80211_rx_mgmt(&rx->sdata->wdev, status->freq, sig,
2430                              rx->skb->data, rx->skb->len,
2431                              GFP_ATOMIC)) {
2432                 if (rx->sta)
2433                         rx->sta->rx_packets++;
2434                 dev_kfree_skb(rx->skb);
2435                 return RX_QUEUED;
2436         }
2437
2438
2439         return RX_CONTINUE;
2440 }
2441
2442 static ieee80211_rx_result debug_noinline
2443 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
2444 {
2445         struct ieee80211_local *local = rx->local;
2446         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2447         struct sk_buff *nskb;
2448         struct ieee80211_sub_if_data *sdata = rx->sdata;
2449         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2450
2451         if (!ieee80211_is_action(mgmt->frame_control))
2452                 return RX_CONTINUE;
2453
2454         /*
2455          * For AP mode, hostapd is responsible for handling any action
2456          * frames that we didn't handle, including returning unknown
2457          * ones. For all other modes we will return them to the sender,
2458          * setting the 0x80 bit in the action category, as required by
2459          * 802.11-2012 9.24.4.
2460          * Newer versions of hostapd shall also use the management frame
2461          * registration mechanisms, but older ones still use cooked
2462          * monitor interfaces so push all frames there.
2463          */
2464         if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
2465             (sdata->vif.type == NL80211_IFTYPE_AP ||
2466              sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
2467                 return RX_DROP_MONITOR;
2468
2469         if (is_multicast_ether_addr(mgmt->da))
2470                 return RX_DROP_MONITOR;
2471
2472         /* do not return rejected action frames */
2473         if (mgmt->u.action.category & 0x80)
2474                 return RX_DROP_UNUSABLE;
2475
2476         nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2477                                GFP_ATOMIC);
2478         if (nskb) {
2479                 struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
2480
2481                 nmgmt->u.action.category |= 0x80;
2482                 memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
2483                 memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2484
2485                 memset(nskb->cb, 0, sizeof(nskb->cb));
2486
2487                 ieee80211_tx_skb(rx->sdata, nskb);
2488         }
2489         dev_kfree_skb(rx->skb);
2490         return RX_QUEUED;
2491 }
2492
2493 static ieee80211_rx_result debug_noinline
2494 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2495 {
2496         struct ieee80211_sub_if_data *sdata = rx->sdata;
2497         struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2498         __le16 stype;
2499
2500         stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2501
2502         if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2503             sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2504             sdata->vif.type != NL80211_IFTYPE_STATION)
2505                 return RX_DROP_MONITOR;
2506
2507         switch (stype) {
2508         case cpu_to_le16(IEEE80211_STYPE_AUTH):
2509         case cpu_to_le16(IEEE80211_STYPE_BEACON):
2510         case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2511                 /* process for all: mesh, mlme, ibss */
2512                 break;
2513         case cpu_to_le16(IEEE80211_STYPE_ASSOC_RESP):
2514         case cpu_to_le16(IEEE80211_STYPE_REASSOC_RESP):
2515         case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2516         case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2517                 if (is_multicast_ether_addr(mgmt->da) &&
2518                     !is_broadcast_ether_addr(mgmt->da))
2519                         return RX_DROP_MONITOR;
2520
2521                 /* process only for station */
2522                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2523                         return RX_DROP_MONITOR;
2524                 break;
2525         case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2526                 /* process only for ibss */
2527                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
2528                         return RX_DROP_MONITOR;
2529                 break;
2530         default:
2531                 return RX_DROP_MONITOR;
2532         }
2533
2534         /* queue up frame and kick off work to process it */
2535         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2536         skb_queue_tail(&sdata->skb_queue, rx->skb);
2537         ieee80211_queue_work(&rx->local->hw, &sdata->work);
2538         if (rx->sta)
2539                 rx->sta->rx_packets++;
2540
2541         return RX_QUEUED;
2542 }
2543
2544 /* TODO: use IEEE80211_RX_FRAGMENTED */
2545 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2546                                         struct ieee80211_rate *rate)
2547 {
2548         struct ieee80211_sub_if_data *sdata;
2549         struct ieee80211_local *local = rx->local;
2550         struct sk_buff *skb = rx->skb, *skb2;
2551         struct net_device *prev_dev = NULL;
2552         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2553         int needed_headroom;
2554
2555         /*
2556          * If cooked monitor has been processed already, then
2557          * don't do it again. If not, set the flag.
2558          */
2559         if (rx->flags & IEEE80211_RX_CMNTR)
2560                 goto out_free_skb;
2561         rx->flags |= IEEE80211_RX_CMNTR;
2562
2563         /* If there are no cooked monitor interfaces, just free the SKB */
2564         if (!local->cooked_mntrs)
2565                 goto out_free_skb;
2566
2567         /* room for the radiotap header based on driver features */
2568         needed_headroom = ieee80211_rx_radiotap_len(local, status);
2569
2570         if (skb_headroom(skb) < needed_headroom &&
2571             pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC))
2572                 goto out_free_skb;
2573
2574         /* prepend radiotap information */
2575         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
2576                                          false);
2577
2578         skb_set_mac_header(skb, 0);
2579         skb->ip_summed = CHECKSUM_UNNECESSARY;
2580         skb->pkt_type = PACKET_OTHERHOST;
2581         skb->protocol = htons(ETH_P_802_2);
2582
2583         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2584                 if (!ieee80211_sdata_running(sdata))
2585                         continue;
2586
2587                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2588                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2589                         continue;
2590
2591                 if (prev_dev) {
2592                         skb2 = skb_clone(skb, GFP_ATOMIC);
2593                         if (skb2) {
2594                                 skb2->dev = prev_dev;
2595                                 netif_receive_skb(skb2);
2596                         }
2597                 }
2598
2599                 prev_dev = sdata->dev;
2600                 sdata->dev->stats.rx_packets++;
2601                 sdata->dev->stats.rx_bytes += skb->len;
2602         }
2603
2604         if (prev_dev) {
2605                 skb->dev = prev_dev;
2606                 netif_receive_skb(skb);
2607                 return;
2608         }
2609
2610  out_free_skb:
2611         dev_kfree_skb(skb);
2612 }
2613
2614 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
2615                                          ieee80211_rx_result res)
2616 {
2617         switch (res) {
2618         case RX_DROP_MONITOR:
2619                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2620                 if (rx->sta)
2621                         rx->sta->rx_dropped++;
2622                 /* fall through */
2623         case RX_CONTINUE: {
2624                 struct ieee80211_rate *rate = NULL;
2625                 struct ieee80211_supported_band *sband;
2626                 struct ieee80211_rx_status *status;
2627
2628                 status = IEEE80211_SKB_RXCB((rx->skb));
2629
2630                 sband = rx->local->hw.wiphy->bands[status->band];
2631                 if (!(status->flag & RX_FLAG_HT))
2632                         rate = &sband->bitrates[status->rate_idx];
2633
2634                 ieee80211_rx_cooked_monitor(rx, rate);
2635                 break;
2636                 }
2637         case RX_DROP_UNUSABLE:
2638                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2639                 if (rx->sta)
2640                         rx->sta->rx_dropped++;
2641                 dev_kfree_skb(rx->skb);
2642                 break;
2643         case RX_QUEUED:
2644                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
2645                 break;
2646         }
2647 }
2648
2649 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx)
2650 {
2651         ieee80211_rx_result res = RX_DROP_MONITOR;
2652         struct sk_buff *skb;
2653
2654 #define CALL_RXH(rxh)                   \
2655         do {                            \
2656                 res = rxh(rx);          \
2657                 if (res != RX_CONTINUE) \
2658                         goto rxh_next;  \
2659         } while (0);
2660
2661         spin_lock(&rx->local->rx_skb_queue.lock);
2662         if (rx->local->running_rx_handler)
2663                 goto unlock;
2664
2665         rx->local->running_rx_handler = true;
2666
2667         while ((skb = __skb_dequeue(&rx->local->rx_skb_queue))) {
2668                 spin_unlock(&rx->local->rx_skb_queue.lock);
2669
2670                 /*
2671                  * all the other fields are valid across frames
2672                  * that belong to an aMPDU since they are on the
2673                  * same TID from the same station
2674                  */
2675                 rx->skb = skb;
2676
2677                 CALL_RXH(ieee80211_rx_h_decrypt)
2678                 CALL_RXH(ieee80211_rx_h_check_more_data)
2679                 CALL_RXH(ieee80211_rx_h_uapsd_and_pspoll)
2680                 CALL_RXH(ieee80211_rx_h_sta_process)
2681                 CALL_RXH(ieee80211_rx_h_defragment)
2682                 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2683                 /* must be after MMIC verify so header is counted in MPDU mic */
2684 #ifdef CONFIG_MAC80211_MESH
2685                 if (ieee80211_vif_is_mesh(&rx->sdata->vif))
2686                         CALL_RXH(ieee80211_rx_h_mesh_fwding);
2687 #endif
2688                 CALL_RXH(ieee80211_rx_h_amsdu)
2689                 CALL_RXH(ieee80211_rx_h_data)
2690                 CALL_RXH(ieee80211_rx_h_ctrl);
2691                 CALL_RXH(ieee80211_rx_h_mgmt_check)
2692                 CALL_RXH(ieee80211_rx_h_action)
2693                 CALL_RXH(ieee80211_rx_h_userspace_mgmt)
2694                 CALL_RXH(ieee80211_rx_h_action_return)
2695                 CALL_RXH(ieee80211_rx_h_mgmt)
2696
2697  rxh_next:
2698                 ieee80211_rx_handlers_result(rx, res);
2699                 spin_lock(&rx->local->rx_skb_queue.lock);
2700 #undef CALL_RXH
2701         }
2702
2703         rx->local->running_rx_handler = false;
2704
2705  unlock:
2706         spin_unlock(&rx->local->rx_skb_queue.lock);
2707 }
2708
2709 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
2710 {
2711         ieee80211_rx_result res = RX_DROP_MONITOR;
2712
2713 #define CALL_RXH(rxh)                   \
2714         do {                            \
2715                 res = rxh(rx);          \
2716                 if (res != RX_CONTINUE) \
2717                         goto rxh_next;  \
2718         } while (0);
2719
2720         CALL_RXH(ieee80211_rx_h_check)
2721
2722         ieee80211_rx_reorder_ampdu(rx);
2723
2724         ieee80211_rx_handlers(rx);
2725         return;
2726
2727  rxh_next:
2728         ieee80211_rx_handlers_result(rx, res);
2729
2730 #undef CALL_RXH
2731 }
2732
2733 /*
2734  * This function makes calls into the RX path, therefore
2735  * it has to be invoked under RCU read lock.
2736  */
2737 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
2738 {
2739         struct ieee80211_rx_data rx = {
2740                 .sta = sta,
2741                 .sdata = sta->sdata,
2742                 .local = sta->local,
2743                 /* This is OK -- must be QoS data frame */
2744                 .security_idx = tid,
2745                 .seqno_idx = tid,
2746                 .flags = 0,
2747         };
2748         struct tid_ampdu_rx *tid_agg_rx;
2749
2750         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
2751         if (!tid_agg_rx)
2752                 return;
2753
2754         spin_lock(&tid_agg_rx->reorder_lock);
2755         ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx);
2756         spin_unlock(&tid_agg_rx->reorder_lock);
2757
2758         ieee80211_rx_handlers(&rx);
2759 }
2760
2761 /* main receive path */
2762
2763 static int prepare_for_handlers(struct ieee80211_rx_data *rx,
2764                                 struct ieee80211_hdr *hdr)
2765 {
2766         struct ieee80211_sub_if_data *sdata = rx->sdata;
2767         struct sk_buff *skb = rx->skb;
2768         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2769         u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2770         int multicast = is_multicast_ether_addr(hdr->addr1);
2771
2772         switch (sdata->vif.type) {
2773         case NL80211_IFTYPE_STATION:
2774                 if (!bssid && !sdata->u.mgd.use_4addr)
2775                         return 0;
2776                 if (!multicast &&
2777                     !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
2778                         if (!(sdata->dev->flags & IFF_PROMISC) ||
2779                             sdata->u.mgd.use_4addr)
2780                                 return 0;
2781                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2782                 }
2783                 break;
2784         case NL80211_IFTYPE_ADHOC:
2785                 if (!bssid)
2786                         return 0;
2787                 if (ieee80211_is_beacon(hdr->frame_control)) {
2788                         return 1;
2789                 } else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2790                         return 0;
2791                 } else if (!multicast &&
2792                            !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
2793                         if (!(sdata->dev->flags & IFF_PROMISC))
2794                                 return 0;
2795                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2796                 } else if (!rx->sta) {
2797                         int rate_idx;
2798                         if (status->flag & RX_FLAG_HT)
2799                                 rate_idx = 0; /* TODO: HT rates */
2800                         else
2801                                 rate_idx = status->rate_idx;
2802                         ieee80211_ibss_rx_no_sta(sdata, bssid, hdr->addr2,
2803                                                  BIT(rate_idx));
2804                 }
2805                 break;
2806         case NL80211_IFTYPE_MESH_POINT:
2807                 if (!multicast &&
2808                     !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
2809                         if (!(sdata->dev->flags & IFF_PROMISC))
2810                                 return 0;
2811
2812                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2813                 }
2814                 break;
2815         case NL80211_IFTYPE_AP_VLAN:
2816         case NL80211_IFTYPE_AP:
2817                 if (!bssid) {
2818                         if (!ether_addr_equal(sdata->vif.addr, hdr->addr1))
2819                                 return 0;
2820                 } else if (!ieee80211_bssid_match(bssid, sdata->vif.addr)) {
2821                         /*
2822                          * Accept public action frames even when the
2823                          * BSSID doesn't match, this is used for P2P
2824                          * and location updates. Note that mac80211
2825                          * itself never looks at these frames.
2826                          */
2827                         if (ieee80211_is_public_action(hdr, skb->len))
2828                                 return 1;
2829                         if (!ieee80211_is_beacon(hdr->frame_control))
2830                                 return 0;
2831                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2832                 }
2833                 break;
2834         case NL80211_IFTYPE_WDS:
2835                 if (bssid || !ieee80211_is_data(hdr->frame_control))
2836                         return 0;
2837                 if (!ether_addr_equal(sdata->u.wds.remote_addr, hdr->addr2))
2838                         return 0;
2839                 break;
2840         case NL80211_IFTYPE_P2P_DEVICE:
2841                 if (!ieee80211_is_public_action(hdr, skb->len) &&
2842                     !ieee80211_is_probe_req(hdr->frame_control) &&
2843                     !ieee80211_is_probe_resp(hdr->frame_control) &&
2844                     !ieee80211_is_beacon(hdr->frame_control))
2845                         return 0;
2846                 if (!ether_addr_equal(sdata->vif.addr, hdr->addr1))
2847                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2848                 break;
2849         default:
2850                 /* should never get here */
2851                 WARN_ON_ONCE(1);
2852                 break;
2853         }
2854
2855         return 1;
2856 }
2857
2858 /*
2859  * This function returns whether or not the SKB
2860  * was destined for RX processing or not, which,
2861  * if consume is true, is equivalent to whether
2862  * or not the skb was consumed.
2863  */
2864 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
2865                                             struct sk_buff *skb, bool consume)
2866 {
2867         struct ieee80211_local *local = rx->local;
2868         struct ieee80211_sub_if_data *sdata = rx->sdata;
2869         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2870         struct ieee80211_hdr *hdr = (void *)skb->data;
2871         int prepares;
2872
2873         rx->skb = skb;
2874         status->rx_flags |= IEEE80211_RX_RA_MATCH;
2875         prepares = prepare_for_handlers(rx, hdr);
2876
2877         if (!prepares)
2878                 return false;
2879
2880         if (!consume) {
2881                 skb = skb_copy(skb, GFP_ATOMIC);
2882                 if (!skb) {
2883                         if (net_ratelimit())
2884                                 wiphy_debug(local->hw.wiphy,
2885                                         "failed to copy skb for %s\n",
2886                                         sdata->name);
2887                         return true;
2888                 }
2889
2890                 rx->skb = skb;
2891         }
2892
2893         ieee80211_invoke_rx_handlers(rx);
2894         return true;
2895 }
2896
2897 /*
2898  * This is the actual Rx frames handler. as it blongs to Rx path it must
2899  * be called with rcu_read_lock protection.
2900  */
2901 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
2902                                          struct sk_buff *skb)
2903 {
2904         struct ieee80211_local *local = hw_to_local(hw);
2905         struct ieee80211_sub_if_data *sdata;
2906         struct ieee80211_hdr *hdr;
2907         __le16 fc;
2908         struct ieee80211_rx_data rx;
2909         struct ieee80211_sub_if_data *prev;
2910         struct sta_info *sta, *tmp, *prev_sta;
2911         int err = 0;
2912
2913         fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
2914         memset(&rx, 0, sizeof(rx));
2915         rx.skb = skb;
2916         rx.local = local;
2917
2918         if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
2919                 local->dot11ReceivedFragmentCount++;
2920
2921         if (ieee80211_is_mgmt(fc))
2922                 err = skb_linearize(skb);
2923         else
2924                 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
2925
2926         if (err) {
2927                 dev_kfree_skb(skb);
2928                 return;
2929         }
2930
2931         hdr = (struct ieee80211_hdr *)skb->data;
2932         ieee80211_parse_qos(&rx);
2933         ieee80211_verify_alignment(&rx);
2934
2935         if (unlikely(ieee80211_is_probe_resp(hdr->frame_control) ||
2936                      ieee80211_is_beacon(hdr->frame_control)))
2937                 ieee80211_scan_rx(local, skb);
2938
2939         if (ieee80211_is_data(fc)) {
2940                 prev_sta = NULL;
2941
2942                 for_each_sta_info(local, hdr->addr2, sta, tmp) {
2943                         if (!prev_sta) {
2944                                 prev_sta = sta;
2945                                 continue;
2946                         }
2947
2948                         rx.sta = prev_sta;
2949                         rx.sdata = prev_sta->sdata;
2950                         ieee80211_prepare_and_rx_handle(&rx, skb, false);
2951
2952                         prev_sta = sta;
2953                 }
2954
2955                 if (prev_sta) {
2956                         rx.sta = prev_sta;
2957                         rx.sdata = prev_sta->sdata;
2958
2959                         if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
2960                                 return;
2961                         goto out;
2962                 }
2963         }
2964
2965         prev = NULL;
2966
2967         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2968                 if (!ieee80211_sdata_running(sdata))
2969                         continue;
2970
2971                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
2972                     sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2973                         continue;
2974
2975                 /*
2976                  * frame is destined for this interface, but if it's
2977                  * not also for the previous one we handle that after
2978                  * the loop to avoid copying the SKB once too much
2979                  */
2980
2981                 if (!prev) {
2982                         prev = sdata;
2983                         continue;
2984                 }
2985
2986                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
2987                 rx.sdata = prev;
2988                 ieee80211_prepare_and_rx_handle(&rx, skb, false);
2989
2990                 prev = sdata;
2991         }
2992
2993         if (prev) {
2994                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
2995                 rx.sdata = prev;
2996
2997                 if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
2998                         return;
2999         }
3000
3001  out:
3002         dev_kfree_skb(skb);
3003 }
3004
3005 /*
3006  * This is the receive path handler. It is called by a low level driver when an
3007  * 802.11 MPDU is received from the hardware.
3008  */
3009 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
3010 {
3011         struct ieee80211_local *local = hw_to_local(hw);
3012         struct ieee80211_rate *rate = NULL;
3013         struct ieee80211_supported_band *sband;
3014         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3015
3016         WARN_ON_ONCE(softirq_count() == 0);
3017
3018         if (WARN_ON(status->band >= IEEE80211_NUM_BANDS))
3019                 goto drop;
3020
3021         sband = local->hw.wiphy->bands[status->band];
3022         if (WARN_ON(!sband))
3023                 goto drop;
3024
3025         /*
3026          * If we're suspending, it is possible although not too likely
3027          * that we'd be receiving frames after having already partially
3028          * quiesced the stack. We can't process such frames then since
3029          * that might, for example, cause stations to be added or other
3030          * driver callbacks be invoked.
3031          */
3032         if (unlikely(local->quiescing || local->suspended))
3033                 goto drop;
3034
3035         /* We might be during a HW reconfig, prevent Rx for the same reason */
3036         if (unlikely(local->in_reconfig))
3037                 goto drop;
3038
3039         /*
3040          * The same happens when we're not even started,
3041          * but that's worth a warning.
3042          */
3043         if (WARN_ON(!local->started))
3044                 goto drop;
3045
3046         if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
3047                 /*
3048                  * Validate the rate, unless a PLCP error means that
3049                  * we probably can't have a valid rate here anyway.
3050                  */
3051
3052                 if (status->flag & RX_FLAG_HT) {
3053                         /*
3054                          * rate_idx is MCS index, which can be [0-76]
3055                          * as documented on:
3056                          *
3057                          * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
3058                          *
3059                          * Anything else would be some sort of driver or
3060                          * hardware error. The driver should catch hardware
3061                          * errors.
3062                          */
3063                         if (WARN(status->rate_idx > 76,
3064                                  "Rate marked as an HT rate but passed "
3065                                  "status->rate_idx is not "
3066                                  "an MCS index [0-76]: %d (0x%02x)\n",
3067                                  status->rate_idx,
3068                                  status->rate_idx))
3069                                 goto drop;
3070                 } else {
3071                         if (WARN_ON(status->rate_idx >= sband->n_bitrates))
3072                                 goto drop;
3073                         rate = &sband->bitrates[status->rate_idx];
3074                 }
3075         }
3076
3077         status->rx_flags = 0;
3078
3079         /*
3080          * key references and virtual interfaces are protected using RCU
3081          * and this requires that we are in a read-side RCU section during
3082          * receive processing
3083          */
3084         rcu_read_lock();
3085
3086         /*
3087          * Frames with failed FCS/PLCP checksum are not returned,
3088          * all other frames are returned without radiotap header
3089          * if it was previously present.
3090          * Also, frames with less than 16 bytes are dropped.
3091          */
3092         skb = ieee80211_rx_monitor(local, skb, rate);
3093         if (!skb) {
3094                 rcu_read_unlock();
3095                 return;
3096         }
3097
3098         ieee80211_tpt_led_trig_rx(local,
3099                         ((struct ieee80211_hdr *)skb->data)->frame_control,
3100                         skb->len);
3101         __ieee80211_rx_handle_packet(hw, skb);
3102
3103         rcu_read_unlock();
3104
3105         return;
3106  drop:
3107         kfree_skb(skb);
3108 }
3109 EXPORT_SYMBOL(ieee80211_rx);
3110
3111 /* This is a version of the rx handler that can be called from hard irq
3112  * context. Post the skb on the queue and schedule the tasklet */
3113 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
3114 {
3115         struct ieee80211_local *local = hw_to_local(hw);
3116
3117         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
3118
3119         skb->pkt_type = IEEE80211_RX_MSG;
3120         skb_queue_tail(&local->skb_queue, skb);
3121         tasklet_schedule(&local->tasklet);
3122 }
3123 EXPORT_SYMBOL(ieee80211_rx_irqsafe);