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         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  44
  45         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
  46                 if (likely(skb->len > FCS_LEN))
  47                         __pskb_trim(skb, skb->len - FCS_LEN);
  48                 else {
  49                         /* driver bug */
  50                         WARN_ON(1);
  51                         dev_kfree_skb(skb);
  52                         return NULL;
  53                 }
  54         }
  55
  56         if (status->vendor_radiotap_len)
  57                 __pskb_pull(skb, status->vendor_radiotap_len);
  58
  59         return skb;
  60 }
  61
  62 static inline int should_drop_frame(struct sk_buff *skb, int present_fcs_len)
  63 {
  64         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  65         struct ieee80211_hdr *hdr;
  66
  67         hdr = (void *)(skb->data + status->vendor_radiotap_len);
  68
  69         if (status->flag & (RX_FLAG_FAILED_FCS_CRC |
  70                             RX_FLAG_FAILED_PLCP_CRC |
  71                             RX_FLAG_AMPDU_IS_ZEROLEN))
  72                 return 1;
  73         if (unlikely(skb->len < 16 + present_fcs_len +
  74                                 status->vendor_radiotap_len))
  75                 return 1;
  76         if (ieee80211_is_ctl(hdr->frame_control) &&
  77             !ieee80211_is_pspoll(hdr->frame_control) &&
  78             !ieee80211_is_back_req(hdr->frame_control))
  79                 return 1;
  80         return 0;
  81 }
  82
  83 static int
  84 ieee80211_rx_radiotap_space(struct ieee80211_local *local,
  85                             struct ieee80211_rx_status *status)
  86 {
  87         int len;
  88
  89         /* always present fields */
  90         len = sizeof(struct ieee80211_radiotap_header) + 9;
  91
  92         /* allocate extra bitmap */
  93         if (status->vendor_radiotap_len)
  94                 len += 4;
  95
  96         if (ieee80211_have_rx_timestamp(status)) {
  97                 len = ALIGN(len, 8);
  98                 len += 8;
  99         }
 100         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
 101                 len += 1;
 102
 103         /* padding for RX_FLAGS if necessary */
 104         len = ALIGN(len, 2);
 105
 106         if (status->flag & RX_FLAG_HT) /* HT info */
 107                 len += 3;
 108
 109         if (status->flag & RX_FLAG_AMPDU_DETAILS) {
 110                 len = ALIGN(len, 4);
 111                 len += 8;
 112         }
 113
 114         if (status->flag & RX_FLAG_VHT) {
 115                 len = ALIGN(len, 2);
 116                 len += 12;
 117         }
 118
 119         if (status->vendor_radiotap_len) {
 120                 if (WARN_ON_ONCE(status->vendor_radiotap_align == 0))
 121                         status->vendor_radiotap_align = 1;
 122                 /* align standard part of vendor namespace */
 123                 len = ALIGN(len, 2);
 124                 /* allocate standard part of vendor namespace */
 125                 len += 6;
 126                 /* align vendor-defined part */
 127                 len = ALIGN(len, status->vendor_radiotap_align);
 128                 /* vendor-defined part is already in skb */
 129         }
 130
 131         return len;
 132 }
 133
 134 /*
 135  * ieee80211_add_rx_radiotap_header - add radiotap header
 136  *
 137  * add a radiotap header containing all the fields which the hardware provided.
 138  */
 139 static void
 140 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
 141                                  struct sk_buff *skb,
 142                                  struct ieee80211_rate *rate,
 143                                  int rtap_len, bool has_fcs)
 144 {
 145         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 146         struct ieee80211_radiotap_header *rthdr;
 147         unsigned char *pos;
 148         u16 rx_flags = 0;
 149         int mpdulen;
 150
 151         mpdulen = skb->len;
 152         if (!(has_fcs && (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)))
 153                 mpdulen += FCS_LEN;
 154
 155         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
 156         memset(rthdr, 0, rtap_len);
 157
 158         /* radiotap header, set always present flags */
 159         rthdr->it_present =
 160                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 161                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
 162                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
 163                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
 164         rthdr->it_len = cpu_to_le16(rtap_len + status->vendor_radiotap_len);
 165
 166         pos = (unsigned char *)(rthdr + 1);
 167
 168         if (status->vendor_radiotap_len) {
 169                 rthdr->it_present |=
 170                         cpu_to_le32(BIT(IEEE80211_RADIOTAP_VENDOR_NAMESPACE)) |
 171                         cpu_to_le32(BIT(IEEE80211_RADIOTAP_EXT));
 172                 put_unaligned_le32(status->vendor_radiotap_bitmap, pos);
 173                 pos += 4;
 174         }
 175
 176         /* the order of the following fields is important */
 177
 178         /* IEEE80211_RADIOTAP_TSFT */
 179         if (ieee80211_have_rx_timestamp(status)) {
 180                 /* padding */
 181                 while ((pos - (u8 *)rthdr) & 7)
 182                         *pos++ = 0;
 183                 put_unaligned_le64(
 184                         ieee80211_calculate_rx_timestamp(local, status,
 185                                                          mpdulen, 0),
 186                         pos);
 187                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
 188                 pos += 8;
 189         }
 190
 191         /* IEEE80211_RADIOTAP_FLAGS */
 192         if (has_fcs && (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS))
 193                 *pos |= IEEE80211_RADIOTAP_F_FCS;
 194         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 195                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
 196         if (status->flag & RX_FLAG_SHORTPRE)
 197                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
 198         pos++;
 199
 200         /* IEEE80211_RADIOTAP_RATE */
 201         if (!rate || status->flag & (RX_FLAG_HT | RX_FLAG_VHT)) {
 202                 /*
 203                  * Without rate information don't add it. If we have,
 204                  * MCS information is a separate field in radiotap,
 205                  * added below. The byte here is needed as padding
 206                  * for the channel though, so initialise it to 0.
 207                  */
 208                 *pos = 0;
 209         } else {
 210                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
 211                 *pos = rate->bitrate / 5;
 212         }
 213         pos++;
 214
 215         /* IEEE80211_RADIOTAP_CHANNEL */
 216         put_unaligned_le16(status->freq, pos);
 217         pos += 2;
 218         if (status->band == IEEE80211_BAND_5GHZ)
 219                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
 220                                    pos);
 221         else if (status->flag & (RX_FLAG_HT | RX_FLAG_VHT))
 222                 put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ,
 223                                    pos);
 224         else if (rate && rate->flags & IEEE80211_RATE_ERP_G)
 225                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
 226                                    pos);
 227         else if (rate)
 228                 put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
 229                                    pos);
 230         else
 231                 put_unaligned_le16(IEEE80211_CHAN_2GHZ, pos);
 232         pos += 2;
 233
 234         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
 235         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM &&
 236             !(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
 237                 *pos = status->signal;
 238                 rthdr->it_present |=
 239                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
 240                 pos++;
 241         }
 242
 243         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
 244
 245         /* IEEE80211_RADIOTAP_ANTENNA */
 246         *pos = status->antenna;
 247         pos++;
 248
 249         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
 250
 251         /* IEEE80211_RADIOTAP_RX_FLAGS */
 252         /* ensure 2 byte alignment for the 2 byte field as required */
 253         if ((pos - (u8 *)rthdr) & 1)
 254                 *pos++ = 0;
 255         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
 256                 rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
 257         put_unaligned_le16(rx_flags, pos);
 258         pos += 2;
 259
 260         if (status->flag & RX_FLAG_HT) {
 261                 unsigned int stbc;
 262
 263                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
 264                 *pos++ = local->hw.radiotap_mcs_details;
 265                 *pos = 0;
 266                 if (status->flag & RX_FLAG_SHORT_GI)
 267                         *pos |= IEEE80211_RADIOTAP_MCS_SGI;
 268                 if (status->flag & RX_FLAG_40MHZ)
 269                         *pos |= IEEE80211_RADIOTAP_MCS_BW_40;
 270                 if (status->flag & RX_FLAG_HT_GF)
 271                         *pos |= IEEE80211_RADIOTAP_MCS_FMT_GF;
 272                 stbc = (status->flag & RX_FLAG_STBC_MASK) >> RX_FLAG_STBC_SHIFT;
 273                 *pos |= stbc << IEEE80211_RADIOTAP_MCS_STBC_SHIFT;
 274                 pos++;
 275                 *pos++ = status->rate_idx;
 276         }
 277
 278         if (status->flag & RX_FLAG_AMPDU_DETAILS) {
 279                 u16 flags = 0;
 280
 281                 /* ensure 4 byte alignment */
 282                 while ((pos - (u8 *)rthdr) & 3)
 283                         pos++;
 284                 rthdr->it_present |=
 285                         cpu_to_le32(1 << IEEE80211_RADIOTAP_AMPDU_STATUS);
 286                 put_unaligned_le32(status->ampdu_reference, pos);
 287                 pos += 4;
 288                 if (status->flag & RX_FLAG_AMPDU_REPORT_ZEROLEN)
 289                         flags |= IEEE80211_RADIOTAP_AMPDU_REPORT_ZEROLEN;
 290                 if (status->flag & RX_FLAG_AMPDU_IS_ZEROLEN)
 291                         flags |= IEEE80211_RADIOTAP_AMPDU_IS_ZEROLEN;
 292                 if (status->flag & RX_FLAG_AMPDU_LAST_KNOWN)
 293                         flags |= IEEE80211_RADIOTAP_AMPDU_LAST_KNOWN;
 294                 if (status->flag & RX_FLAG_AMPDU_IS_LAST)
 295                         flags |= IEEE80211_RADIOTAP_AMPDU_IS_LAST;
 296                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_ERROR)
 297                         flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_ERR;
 298                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
 299                         flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_KNOWN;
 300                 put_unaligned_le16(flags, pos);
 301                 pos += 2;
 302                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
 303                         *pos++ = status->ampdu_delimiter_crc;
 304                 else
 305                         *pos++ = 0;
 306                 *pos++ = 0;
 307         }
 308
 309         if (status->flag & RX_FLAG_VHT) {
 310                 u16 known = local->hw.radiotap_vht_details;
 311
 312                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_VHT);
 313                 /* known field - how to handle 80+80? */
 314                 if (status->flag & RX_FLAG_80P80MHZ)
 315                         known &= ~IEEE80211_RADIOTAP_VHT_KNOWN_BANDWIDTH;
 316                 put_unaligned_le16(known, pos);
 317                 pos += 2;
 318                 /* flags */
 319                 if (status->flag & RX_FLAG_SHORT_GI)
 320                         *pos |= IEEE80211_RADIOTAP_VHT_FLAG_SGI;
 321                 pos++;
 322                 /* bandwidth */
 323                 if (status->flag & RX_FLAG_80MHZ)
 324                         *pos++ = 4;
 325                 else if (status->flag & RX_FLAG_80P80MHZ)
 326                         *pos++ = 0; /* marked not known above */
 327                 else if (status->flag & RX_FLAG_160MHZ)
 328                         *pos++ = 11;
 329                 else if (status->flag & RX_FLAG_40MHZ)
 330                         *pos++ = 1;
 331                 else /* 20 MHz */
 332                         *pos++ = 0;
 333                 /* MCS/NSS */
 334                 *pos = (status->rate_idx << 4) | status->vht_nss;
 335                 pos += 4;
 336                 /* coding field */
 337                 pos++;
 338                 /* group ID */
 339                 pos++;
 340                 /* partial_aid */
 341                 pos += 2;
 342         }
 343
 344         if (status->vendor_radiotap_len) {
 345                 /* ensure 2 byte alignment for the vendor field as required */
 346                 if ((pos - (u8 *)rthdr) & 1)
 347                         *pos++ = 0;
 348                 *pos++ = status->vendor_radiotap_oui[0];
 349                 *pos++ = status->vendor_radiotap_oui[1];
 350                 *pos++ = status->vendor_radiotap_oui[2];
 351                 *pos++ = status->vendor_radiotap_subns;
 352                 put_unaligned_le16(status->vendor_radiotap_len, pos);
 353                 pos += 2;
 354                 /* align the actual payload as requested */
 355                 while ((pos - (u8 *)rthdr) & (status->vendor_radiotap_align - 1))
 356                         *pos++ = 0;
 357         }
 358 }
 359
 360 /*
 361  * This function copies a received frame to all monitor interfaces and
 362  * returns a cleaned-up SKB that no longer includes the FCS nor the
 363  * radiotap header the driver might have added.
 364  */
 365 static struct sk_buff *
 366 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
 367                      struct ieee80211_rate *rate)
 368 {
 369         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
 370         struct ieee80211_sub_if_data *sdata;
 371         int needed_headroom;
 372         struct sk_buff *skb, *skb2;
 373         struct net_device *prev_dev = NULL;
 374         int present_fcs_len = 0;
 375
 376         /*
 377          * First, we may need to make a copy of the skb because
 378          *  (1) we need to modify it for radiotap (if not present), and
 379          *  (2) the other RX handlers will modify the skb we got.
 380          *
 381          * We don't need to, of course, if we aren't going to return
 382          * the SKB because it has a bad FCS/PLCP checksum.
 383          */
 384
 385         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 386                 present_fcs_len = FCS_LEN;
 387
 388         /* ensure hdr->frame_control and vendor radiotap data are in skb head */
 389         if (!pskb_may_pull(origskb, 2 + status->vendor_radiotap_len)) {
 390                 dev_kfree_skb(origskb);
 391                 return NULL;
 392         }
 393
 394         if (!local->monitors) {
 395                 if (should_drop_frame(origskb, present_fcs_len)) {
 396                         dev_kfree_skb(origskb);
 397                         return NULL;
 398                 }
 399
 400                 return remove_monitor_info(local, origskb);
 401         }
 402
 403         /* room for the radiotap header based on driver features */
 404         needed_headroom = ieee80211_rx_radiotap_space(local, status);
 405
 406         if (should_drop_frame(origskb, present_fcs_len)) {
 407                 /* only need to expand headroom if necessary */
 408                 skb = origskb;
 409                 origskb = NULL;
 410
 411                 /*
 412                  * This shouldn't trigger often because most devices have an
 413                  * RX header they pull before we get here, and that should
 414                  * be big enough for our radiotap information. We should
 415                  * probably export the length to drivers so that we can have
 416                  * them allocate enough headroom to start with.
 417                  */
 418                 if (skb_headroom(skb) < needed_headroom &&
 419                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
 420                         dev_kfree_skb(skb);
 421                         return NULL;
 422                 }
 423         } else {
 424                 /*
 425                  * Need to make a copy and possibly remove radiotap header
 426                  * and FCS from the original.
 427                  */
 428                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
 429
 430                 origskb = remove_monitor_info(local, origskb);
 431
 432                 if (!skb)
 433                         return origskb;
 434         }
 435
 436         /* prepend radiotap information */
 437         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
 438                                          true);
 439
 440         skb_reset_mac_header(skb);
 441         skb->ip_summed = CHECKSUM_UNNECESSARY;
 442         skb->pkt_type = PACKET_OTHERHOST;
 443         skb->protocol = htons(ETH_P_802_2);
 444
 445         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 446                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
 447                         continue;
 448
 449                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
 450                         continue;
 451
 452                 if (!ieee80211_sdata_running(sdata))
 453                         continue;
 454
 455                 if (prev_dev) {
 456                         skb2 = skb_clone(skb, GFP_ATOMIC);
 457                         if (skb2) {
 458                                 skb2->dev = prev_dev;
 459                                 netif_receive_skb(skb2);
 460                         }
 461                 }
 462
 463                 prev_dev = sdata->dev;
 464                 sdata->dev->stats.rx_packets++;
 465                 sdata->dev->stats.rx_bytes += skb->len;
 466         }
 467
 468         if (prev_dev) {
 469                 skb->dev = prev_dev;
 470                 netif_receive_skb(skb);
 471         } else
 472                 dev_kfree_skb(skb);
 473
 474         return origskb;
 475 }
 476
 477 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
 478 {
 479         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 480         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 481         int tid, seqno_idx, security_idx;
 482
 483         /* does the frame have a qos control field? */
 484         if (ieee80211_is_data_qos(hdr->frame_control)) {
 485                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 486                 /* frame has qos control */
 487                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
 488                 if (*qc & IEEE80211_QOS_CTL_A_MSDU_PRESENT)
 489                         status->rx_flags |= IEEE80211_RX_AMSDU;
 490
 491                 seqno_idx = tid;
 492                 security_idx = tid;
 493         } else {
 494                 /*
 495                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
 496                  *
 497                  *      Sequence numbers for management frames, QoS data
 498                  *      frames with a broadcast/multicast address in the
 499                  *      Address 1 field, and all non-QoS data frames sent
 500                  *      by QoS STAs are assigned using an additional single
 501                  *      modulo-4096 counter, [...]
 502                  *
 503                  * We also use that counter for non-QoS STAs.
 504                  */
 505                 seqno_idx = IEEE80211_NUM_TIDS;
 506                 security_idx = 0;
 507                 if (ieee80211_is_mgmt(hdr->frame_control))
 508                         security_idx = IEEE80211_NUM_TIDS;
 509                 tid = 0;
 510         }
 511
 512         rx->seqno_idx = seqno_idx;
 513         rx->security_idx = security_idx;
 514         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 515          * For now, set skb->priority to 0 for other cases. */
 516         rx->skb->priority = (tid > 7) ? 0 : tid;
 517 }
 518
 519 /**
 520  * DOC: Packet alignment
 521  *
 522  * Drivers always need to pass packets that are aligned to two-byte boundaries
 523  * to the stack.
 524  *
 525  * Additionally, should, if possible, align the payload data in a way that
 526  * guarantees that the contained IP header is aligned to a four-byte
 527  * boundary. In the case of regular frames, this simply means aligning the
 528  * payload to a four-byte boundary (because either the IP header is directly
 529  * contained, or IV/RFC1042 headers that have a length divisible by four are
 530  * in front of it).  If the payload data is not properly aligned and the
 531  * architecture doesn't support efficient unaligned operations, mac80211
 532  * will align the data.
 533  *
 534  * With A-MSDU frames, however, the payload data address must yield two modulo
 535  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
 536  * push the IP header further back to a multiple of four again. Thankfully, the
 537  * specs were sane enough this time around to require padding each A-MSDU
 538  * subframe to a length that is a multiple of four.
 539  *
 540  * Padding like Atheros hardware adds which is between the 802.11 header and
 541  * the payload is not supported, the driver is required to move the 802.11
 542  * header to be directly in front of the payload in that case.
 543  */
 544 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
 545 {
 546 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 547         WARN_ONCE((unsigned long)rx->skb->data & 1,
 548                   "unaligned packet at 0x%p\n", rx->skb->data);
 549 #endif
 550 }
 551
 552
 553 /* rx handlers */
 554
 555 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
 556 {
 557         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 558
 559         if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
 560                 return 0;
 561
 562         return ieee80211_is_robust_mgmt_frame(hdr);
 563 }
 564
 565
 566 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
 567 {
 568         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 569
 570         if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
 571                 return 0;
 572
 573         return ieee80211_is_robust_mgmt_frame(hdr);
 574 }
 575
 576
 577 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
 578 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
 579 {
 580         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
 581         struct ieee80211_mmie *mmie;
 582
 583         if (skb->len < 24 + sizeof(*mmie) || !is_multicast_ether_addr(hdr->da))
 584                 return -1;
 585
 586         if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
 587                 return -1; /* not a robust management frame */
 588
 589         mmie = (struct ieee80211_mmie *)
 590                 (skb->data + skb->len - sizeof(*mmie));
 591         if (mmie->element_id != WLAN_EID_MMIE ||
 592             mmie->length != sizeof(*mmie) - 2)
 593                 return -1;
 594
 595         return le16_to_cpu(mmie->key_id);
 596 }
 597
 598 static ieee80211_rx_result ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
 599 {
 600         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 601         char *dev_addr = rx->sdata->vif.addr;
 602
 603         if (ieee80211_is_data(hdr->frame_control)) {
 604                 if (is_multicast_ether_addr(hdr->addr1)) {
 605                         if (ieee80211_has_tods(hdr->frame_control) ||
 606                             !ieee80211_has_fromds(hdr->frame_control))
 607                                 return RX_DROP_MONITOR;
 608                         if (ether_addr_equal(hdr->addr3, dev_addr))
 609                                 return RX_DROP_MONITOR;
 610                 } else {
 611                         if (!ieee80211_has_a4(hdr->frame_control))
 612                                 return RX_DROP_MONITOR;
 613                         if (ether_addr_equal(hdr->addr4, dev_addr))
 614                                 return RX_DROP_MONITOR;
 615                 }
 616         }
 617
 618         /* If there is not an established peer link and this is not a peer link
 619          * establisment frame, beacon or probe, drop the frame.
 620          */
 621
 622         if (!rx->sta || sta_plink_state(rx->sta) != NL80211_PLINK_ESTAB) {
 623                 struct ieee80211_mgmt *mgmt;
 624
 625                 if (!ieee80211_is_mgmt(hdr->frame_control))
 626                         return RX_DROP_MONITOR;
 627
 628                 if (ieee80211_is_action(hdr->frame_control)) {
 629                         u8 category;
 630
 631                         /* make sure category field is present */
 632                         if (rx->skb->len < IEEE80211_MIN_ACTION_SIZE)
 633                                 return RX_DROP_MONITOR;
 634
 635                         mgmt = (struct ieee80211_mgmt *)hdr;
 636                         category = mgmt->u.action.category;
 637                         if (category != WLAN_CATEGORY_MESH_ACTION &&
 638                             category != WLAN_CATEGORY_SELF_PROTECTED)
 639                                 return RX_DROP_MONITOR;
 640                         return RX_CONTINUE;
 641                 }
 642
 643                 if (ieee80211_is_probe_req(hdr->frame_control) ||
 644                     ieee80211_is_probe_resp(hdr->frame_control) ||
 645                     ieee80211_is_beacon(hdr->frame_control) ||
 646                     ieee80211_is_auth(hdr->frame_control))
 647                         return RX_CONTINUE;
 648
 649                 return RX_DROP_MONITOR;
 650         }
 651
 652         return RX_CONTINUE;
 653 }
 654
 655 static void ieee80211_release_reorder_frame(struct ieee80211_sub_if_data *sdata,
 656                                             struct tid_ampdu_rx *tid_agg_rx,
 657                                             int index,
 658                                             struct sk_buff_head *frames)
 659 {
 660         struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
 661         struct ieee80211_rx_status *status;
 662
 663         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 664
 665         if (!skb)
 666                 goto no_frame;
 667
 668         /* release the frame from the reorder ring buffer */
 669         tid_agg_rx->stored_mpdu_num--;
 670         tid_agg_rx->reorder_buf[index] = NULL;
 671         status = IEEE80211_SKB_RXCB(skb);
 672         status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE;
 673         __skb_queue_tail(frames, skb);
 674
 675 no_frame:
 676         tid_agg_rx->head_seq_num = ieee80211_sn_inc(tid_agg_rx->head_seq_num);
 677 }
 678
 679 static void ieee80211_release_reorder_frames(struct ieee80211_sub_if_data *sdata,
 680                                              struct tid_ampdu_rx *tid_agg_rx,
 681                                              u16 head_seq_num,
 682                                              struct sk_buff_head *frames)
 683 {
 684         int index;
 685
 686         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 687
 688         while (ieee80211_sn_less(tid_agg_rx->head_seq_num, head_seq_num)) {
 689                 index = ieee80211_sn_sub(tid_agg_rx->head_seq_num,
 690                                          tid_agg_rx->ssn) %
 691                                                         tid_agg_rx->buf_size;
 692                 ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
 693                                                 frames);
 694         }
 695 }
 696
 697 /*
 698  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
 699  * the skb was added to the buffer longer than this time ago, the earlier
 700  * frames that have not yet been received are assumed to be lost and the skb
 701  * can be released for processing. This may also release other skb's from the
 702  * reorder buffer if there are no additional gaps between the frames.
 703  *
 704  * Callers must hold tid_agg_rx->reorder_lock.
 705  */
 706 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
 707
 708 static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata,
 709                                           struct tid_ampdu_rx *tid_agg_rx,
 710                                           struct sk_buff_head *frames)
 711 {
 712         int index, j;
 713
 714         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 715
 716         /* release the buffer until next missing frame */
 717         index = ieee80211_sn_sub(tid_agg_rx->head_seq_num,
 718                                  tid_agg_rx->ssn) % tid_agg_rx->buf_size;
 719         if (!tid_agg_rx->reorder_buf[index] &&
 720             tid_agg_rx->stored_mpdu_num) {
 721                 /*
 722                  * No buffers ready to be released, but check whether any
 723                  * frames in the reorder buffer have timed out.
 724                  */
 725                 int skipped = 1;
 726                 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
 727                      j = (j + 1) % tid_agg_rx->buf_size) {
 728                         if (!tid_agg_rx->reorder_buf[j]) {
 729                                 skipped++;
 730                                 continue;
 731                         }
 732                         if (skipped &&
 733                             !time_after(jiffies, tid_agg_rx->reorder_time[j] +
 734                                         HT_RX_REORDER_BUF_TIMEOUT))
 735                                 goto set_release_timer;
 736
 737                         ht_dbg_ratelimited(sdata,
 738                                            "release an RX reorder frame due to timeout on earlier frames\n");
 739                         ieee80211_release_reorder_frame(sdata, tid_agg_rx, j,
 740                                                         frames);
 741
 742                         /*
 743                          * Increment the head seq# also for the skipped slots.
 744                          */
 745                         tid_agg_rx->head_seq_num =
 746                                 (tid_agg_rx->head_seq_num +
 747                                  skipped) & IEEE80211_SN_MASK;
 748                         skipped = 0;
 749                 }
 750         } else while (tid_agg_rx->reorder_buf[index]) {
 751                 ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
 752                                                 frames);
 753                 index = ieee80211_sn_sub(tid_agg_rx->head_seq_num,
 754                                          tid_agg_rx->ssn) %
 755                                                         tid_agg_rx->buf_size;
 756         }
 757
 758         if (tid_agg_rx->stored_mpdu_num) {
 759                 j = index = ieee80211_sn_sub(tid_agg_rx->head_seq_num,
 760                                              tid_agg_rx->ssn) %
 761                                                         tid_agg_rx->buf_size;
 762
 763                 for (; j != (index - 1) % tid_agg_rx->buf_size;
 764                      j = (j + 1) % tid_agg_rx->buf_size) {
 765                         if (tid_agg_rx->reorder_buf[j])
 766                                 break;
 767                 }
 768
 769  set_release_timer:
 770
 771                 mod_timer(&tid_agg_rx->reorder_timer,
 772                           tid_agg_rx->reorder_time[j] + 1 +
 773                           HT_RX_REORDER_BUF_TIMEOUT);
 774         } else {
 775                 del_timer(&tid_agg_rx->reorder_timer);
 776         }
 777 }
 778
 779 /*
 780  * As this function belongs to the RX path it must be under
 781  * rcu_read_lock protection. It returns false if the frame
 782  * can be processed immediately, true if it was consumed.
 783  */
 784 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_sub_if_data *sdata,
 785                                              struct tid_ampdu_rx *tid_agg_rx,
 786                                              struct sk_buff *skb,
 787                                              struct sk_buff_head *frames)
 788 {
 789         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 790         u16 sc = le16_to_cpu(hdr->seq_ctrl);
 791         u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
 792         u16 head_seq_num, buf_size;
 793         int index;
 794         bool ret = true;
 795
 796         spin_lock(&tid_agg_rx->reorder_lock);
 797
 798         buf_size = tid_agg_rx->buf_size;
 799         head_seq_num = tid_agg_rx->head_seq_num;
 800
 801         /* frame with out of date sequence number */
 802         if (ieee80211_sn_less(mpdu_seq_num, head_seq_num)) {
 803                 dev_kfree_skb(skb);
 804                 goto out;
 805         }
 806
 807         /*
 808          * If frame the sequence number exceeds our buffering window
 809          * size release some previous frames to make room for this one.
 810          */
 811         if (!ieee80211_sn_less(mpdu_seq_num, head_seq_num + buf_size)) {
 812                 head_seq_num = ieee80211_sn_inc(
 813                                 ieee80211_sn_sub(mpdu_seq_num, buf_size));
 814                 /* release stored frames up to new head to stack */
 815                 ieee80211_release_reorder_frames(sdata, tid_agg_rx,
 816                                                  head_seq_num, frames);
 817         }
 818
 819         /* Now the new frame is always in the range of the reordering buffer */
 820
 821         index = ieee80211_sn_sub(mpdu_seq_num,
 822                                  tid_agg_rx->ssn) % tid_agg_rx->buf_size;
 823
 824         /* check if we already stored this frame */
 825         if (tid_agg_rx->reorder_buf[index]) {
 826                 dev_kfree_skb(skb);
 827                 goto out;
 828         }
 829
 830         /*
 831          * If the current MPDU is in the right order and nothing else
 832          * is stored we can process it directly, no need to buffer it.
 833          * If it is first but there's something stored, we may be able
 834          * to release frames after this one.
 835          */
 836         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
 837             tid_agg_rx->stored_mpdu_num == 0) {
 838                 tid_agg_rx->head_seq_num =
 839                         ieee80211_sn_inc(tid_agg_rx->head_seq_num);
 840                 ret = false;
 841                 goto out;
 842         }
 843
 844         /* put the frame in the reordering buffer */
 845         tid_agg_rx->reorder_buf[index] = skb;
 846         tid_agg_rx->reorder_time[index] = jiffies;
 847         tid_agg_rx->stored_mpdu_num++;
 848         ieee80211_sta_reorder_release(sdata, tid_agg_rx, frames);
 849
 850  out:
 851         spin_unlock(&tid_agg_rx->reorder_lock);
 852         return ret;
 853 }
 854
 855 /*
 856  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
 857  * true if the MPDU was buffered, false if it should be processed.
 858  */
 859 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
 860                                        struct sk_buff_head *frames)
 861 {
 862         struct sk_buff *skb = rx->skb;
 863         struct ieee80211_local *local = rx->local;
 864         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 865         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 866         struct sta_info *sta = rx->sta;
 867         struct tid_ampdu_rx *tid_agg_rx;
 868         u16 sc;
 869         u8 tid, ack_policy;
 870
 871         if (!ieee80211_is_data_qos(hdr->frame_control))
 872                 goto dont_reorder;
 873
 874         /*
 875          * filter the QoS data rx stream according to
 876          * STA/TID and check if this STA/TID is on aggregation
 877          */
 878
 879         if (!sta)
 880                 goto dont_reorder;
 881
 882         ack_policy = *ieee80211_get_qos_ctl(hdr) &
 883                      IEEE80211_QOS_CTL_ACK_POLICY_MASK;
 884         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
 885
 886         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
 887         if (!tid_agg_rx)
 888                 goto dont_reorder;
 889
 890         /* qos null data frames are excluded */
 891         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
 892                 goto dont_reorder;
 893
 894         /* not part of a BA session */
 895         if (ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
 896             ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_NORMAL)
 897                 goto dont_reorder;
 898
 899         /* not actually part of this BA session */
 900         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
 901                 goto dont_reorder;
 902
 903         /* new, potentially un-ordered, ampdu frame - process it */
 904
 905         /* reset session timer */
 906         if (tid_agg_rx->timeout)
 907                 tid_agg_rx->last_rx = jiffies;
 908
 909         /* if this mpdu is fragmented - terminate rx aggregation session */
 910         sc = le16_to_cpu(hdr->seq_ctrl);
 911         if (sc & IEEE80211_SCTL_FRAG) {
 912                 skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
 913                 skb_queue_tail(&rx->sdata->skb_queue, skb);
 914                 ieee80211_queue_work(&local->hw, &rx->sdata->work);
 915                 return;
 916         }
 917
 918         /*
 919          * No locking needed -- we will only ever process one
 920          * RX packet at a time, and thus own tid_agg_rx. All
 921          * other code manipulating it needs to (and does) make
 922          * sure that we cannot get to it any more before doing
 923          * anything with it.
 924          */
 925         if (ieee80211_sta_manage_reorder_buf(rx->sdata, tid_agg_rx, skb,
 926                                              frames))
 927                 return;
 928
 929  dont_reorder:
 930         __skb_queue_tail(frames, skb);
 931 }
 932
 933 static ieee80211_rx_result debug_noinline
 934 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
 935 {
 936         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 937         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 938
 939         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 940         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 941                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
 942                              rx->sta->last_seq_ctrl[rx->seqno_idx] ==
 943                              hdr->seq_ctrl)) {
 944                         if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
 945                                 rx->local->dot11FrameDuplicateCount++;
 946                                 rx->sta->num_duplicates++;
 947                         }
 948                         return RX_DROP_UNUSABLE;
 949                 } else
 950                         rx->sta->last_seq_ctrl[rx->seqno_idx] = hdr->seq_ctrl;
 951         }
 952
 953         if (unlikely(rx->skb->len < 16)) {
 954                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 955                 return RX_DROP_MONITOR;
 956         }
 957
 958         /* Drop disallowed frame classes based on STA auth/assoc state;
 959          * IEEE 802.11, Chap 5.5.
 960          *
 961          * mac80211 filters only based on association state, i.e. it drops
 962          * Class 3 frames from not associated stations. hostapd sends
 963          * deauth/disassoc frames when needed. In addition, hostapd is
 964          * responsible for filtering on both auth and assoc states.
 965          */
 966
 967         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
 968                 return ieee80211_rx_mesh_check(rx);
 969
 970         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
 971                       ieee80211_is_pspoll(hdr->frame_control)) &&
 972                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
 973                      rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
 974                      (!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_ASSOC)))) {
 975                 /*
 976                  * accept port control frames from the AP even when it's not
 977                  * yet marked ASSOC to prevent a race where we don't set the
 978                  * assoc bit quickly enough before it sends the first frame
 979                  */
 980                 if (rx->sta && rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
 981                     ieee80211_is_data_present(hdr->frame_control)) {
 982                         unsigned int hdrlen;
 983                         __be16 ethertype;
 984
 985                         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 986
 987                         if (rx->skb->len < hdrlen + 8)
 988                                 return RX_DROP_MONITOR;
 989
 990                         skb_copy_bits(rx->skb, hdrlen + 6, &ethertype, 2);
 991                         if (ethertype == rx->sdata->control_port_protocol)
 992                                 return RX_CONTINUE;
 993                 }
 994
 995                 if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
 996                     cfg80211_rx_spurious_frame(rx->sdata->dev,
 997                                                hdr->addr2,
 998                                                GFP_ATOMIC))
 999                         return RX_DROP_UNUSABLE;
1000
1001                 return RX_DROP_MONITOR;
1002         }
1003
1004         return RX_CONTINUE;
1005 }
1006
1007
1008 static ieee80211_rx_result debug_noinline
1009 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
1010 {
1011         struct sk_buff *skb = rx->skb;
1012         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1013         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1014         int keyidx;
1015         int hdrlen;
1016         ieee80211_rx_result result = RX_DROP_UNUSABLE;
1017         struct ieee80211_key *sta_ptk = NULL;
1018         int mmie_keyidx = -1;
1019         __le16 fc;
1020
1021         /*
1022          * Key selection 101
1023          *
1024          * There are four types of keys:
1025          *  - GTK (group keys)
1026          *  - IGTK (group keys for management frames)
1027          *  - PTK (pairwise keys)
1028          *  - STK (station-to-station pairwise keys)
1029          *
1030          * When selecting a key, we have to distinguish between multicast
1031          * (including broadcast) and unicast frames, the latter can only
1032          * use PTKs and STKs while the former always use GTKs and IGTKs.
1033          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
1034          * unicast frames can also use key indices like GTKs. Hence, if we
1035          * don't have a PTK/STK we check the key index for a WEP key.
1036          *
1037          * Note that in a regular BSS, multicast frames are sent by the
1038          * AP only, associated stations unicast the frame to the AP first
1039          * which then multicasts it on their behalf.
1040          *
1041          * There is also a slight problem in IBSS mode: GTKs are negotiated
1042          * with each station, that is something we don't currently handle.
1043          * The spec seems to expect that one negotiates the same key with
1044          * every station but there's no such requirement; VLANs could be
1045          * possible.
1046          */
1047
1048         /*
1049          * No point in finding a key and decrypting if the frame is neither
1050          * addressed to us nor a multicast frame.
1051          */
1052         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1053                 return RX_CONTINUE;
1054
1055         /* start without a key */
1056         rx->key = NULL;
1057
1058         if (rx->sta)
1059                 sta_ptk = rcu_dereference(rx->sta->ptk);
1060
1061         fc = hdr->frame_control;
1062
1063         if (!ieee80211_has_protected(fc))
1064                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
1065
1066         if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
1067                 rx->key = sta_ptk;
1068                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1069                     (status->flag & RX_FLAG_IV_STRIPPED))
1070                         return RX_CONTINUE;
1071                 /* Skip decryption if the frame is not protected. */
1072                 if (!ieee80211_has_protected(fc))
1073                         return RX_CONTINUE;
1074         } else if (mmie_keyidx >= 0) {
1075                 /* Broadcast/multicast robust management frame / BIP */
1076                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1077                     (status->flag & RX_FLAG_IV_STRIPPED))
1078                         return RX_CONTINUE;
1079
1080                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
1081                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
1082                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
1083                 if (rx->sta)
1084                         rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
1085                 if (!rx->key)
1086                         rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
1087         } else if (!ieee80211_has_protected(fc)) {
1088                 /*
1089                  * The frame was not protected, so skip decryption. However, we
1090                  * need to set rx->key if there is a key that could have been
1091                  * used so that the frame may be dropped if encryption would
1092                  * have been expected.
1093                  */
1094                 struct ieee80211_key *key = NULL;
1095                 struct ieee80211_sub_if_data *sdata = rx->sdata;
1096                 int i;
1097
1098                 if (ieee80211_is_mgmt(fc) &&
1099                     is_multicast_ether_addr(hdr->addr1) &&
1100                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
1101                         rx->key = key;
1102                 else {
1103                         if (rx->sta) {
1104                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1105                                         key = rcu_dereference(rx->sta->gtk[i]);
1106                                         if (key)
1107                                                 break;
1108                                 }
1109                         }
1110                         if (!key) {
1111                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1112                                         key = rcu_dereference(sdata->keys[i]);
1113                                         if (key)
1114                                                 break;
1115                                 }
1116                         }
1117                         if (key)
1118                                 rx->key = key;
1119                 }
1120                 return RX_CONTINUE;
1121         } else {
1122                 u8 keyid;
1123                 /*
1124                  * The device doesn't give us the IV so we won't be
1125                  * able to look up the key. That's ok though, we
1126                  * don't need to decrypt the frame, we just won't
1127                  * be able to keep statistics accurate.
1128                  * Except for key threshold notifications, should
1129                  * we somehow allow the driver to tell us which key
1130                  * the hardware used if this flag is set?
1131                  */
1132                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1133                     (status->flag & RX_FLAG_IV_STRIPPED))
1134                         return RX_CONTINUE;
1135
1136                 hdrlen = ieee80211_hdrlen(fc);
1137
1138                 if (rx->skb->len < 8 + hdrlen)
1139                         return RX_DROP_UNUSABLE; /* TODO: count this? */
1140
1141                 /*
1142                  * no need to call ieee80211_wep_get_keyidx,
1143                  * it verifies a bunch of things we've done already
1144                  */
1145                 skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
1146                 keyidx = keyid >> 6;
1147
1148                 /* check per-station GTK first, if multicast packet */
1149                 if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
1150                         rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
1151
1152                 /* if not found, try default key */
1153                 if (!rx->key) {
1154                         rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
1155
1156                         /*
1157                          * RSNA-protected unicast frames should always be
1158                          * sent with pairwise or station-to-station keys,
1159                          * but for WEP we allow using a key index as well.
1160                          */
1161                         if (rx->key &&
1162                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1163                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1164                             !is_multicast_ether_addr(hdr->addr1))
1165                                 rx->key = NULL;
1166                 }
1167         }
1168
1169         if (rx->key) {
1170                 if (unlikely(rx->key->flags & KEY_FLAG_TAINTED))
1171                         return RX_DROP_MONITOR;
1172
1173                 rx->key->tx_rx_count++;
1174                 /* TODO: add threshold stuff again */
1175         } else {
1176                 return RX_DROP_MONITOR;
1177         }
1178
1179         switch (rx->key->conf.cipher) {
1180         case WLAN_CIPHER_SUITE_WEP40:
1181         case WLAN_CIPHER_SUITE_WEP104:
1182                 result = ieee80211_crypto_wep_decrypt(rx);
1183                 break;
1184         case WLAN_CIPHER_SUITE_TKIP:
1185                 result = ieee80211_crypto_tkip_decrypt(rx);
1186                 break;
1187         case WLAN_CIPHER_SUITE_CCMP:
1188                 result = ieee80211_crypto_ccmp_decrypt(rx);
1189                 break;
1190         case WLAN_CIPHER_SUITE_AES_CMAC:
1191                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
1192                 break;
1193         default:
1194                 /*
1195                  * We can reach here only with HW-only algorithms
1196                  * but why didn't it decrypt the frame?!
1197                  */
1198                 return RX_DROP_UNUSABLE;
1199         }
1200
1201         /* the hdr variable is invalid after the decrypt handlers */
1202
1203         /* either the frame has been decrypted or will be dropped */
1204         status->flag |= RX_FLAG_DECRYPTED;
1205
1206         return result;
1207 }
1208
1209 static ieee80211_rx_result debug_noinline
1210 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1211 {
1212         struct ieee80211_local *local;
1213         struct ieee80211_hdr *hdr;
1214         struct sk_buff *skb;
1215
1216         local = rx->local;
1217         skb = rx->skb;
1218         hdr = (struct ieee80211_hdr *) skb->data;
1219
1220         if (!local->pspolling)
1221                 return RX_CONTINUE;
1222
1223         if (!ieee80211_has_fromds(hdr->frame_control))
1224                 /* this is not from AP */
1225                 return RX_CONTINUE;
1226
1227         if (!ieee80211_is_data(hdr->frame_control))
1228                 return RX_CONTINUE;
1229
1230         if (!ieee80211_has_moredata(hdr->frame_control)) {
1231                 /* AP has no more frames buffered for us */
1232                 local->pspolling = false;
1233                 return RX_CONTINUE;
1234         }
1235
1236         /* more data bit is set, let's request a new frame from the AP */
1237         ieee80211_send_pspoll(local, rx->sdata);
1238
1239         return RX_CONTINUE;
1240 }
1241
1242 static void sta_ps_start(struct sta_info *sta)
1243 {
1244         struct ieee80211_sub_if_data *sdata = sta->sdata;
1245         struct ieee80211_local *local = sdata->local;
1246         struct ps_data *ps;
1247
1248         if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
1249             sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1250                 ps = &sdata->bss->ps;
1251         else
1252                 return;
1253
1254         atomic_inc(&ps->num_sta_ps);
1255         set_sta_flag(sta, WLAN_STA_PS_STA);
1256         if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
1257                 drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1258         ps_dbg(sdata, "STA %pM aid %d enters power save mode\n",
1259                sta->sta.addr, sta->sta.aid);
1260 }
1261
1262 static void sta_ps_end(struct sta_info *sta)
1263 {
1264         ps_dbg(sta->sdata, "STA %pM aid %d exits power save mode\n",
1265                sta->sta.addr, sta->sta.aid);
1266
1267         if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) {
1268                 ps_dbg(sta->sdata, "STA %pM aid %d driver-ps-blocked\n",
1269                        sta->sta.addr, sta->sta.aid);
1270                 return;
1271         }
1272
1273         ieee80211_sta_ps_deliver_wakeup(sta);
1274 }
1275
1276 int ieee80211_sta_ps_transition(struct ieee80211_sta *sta, bool start)
1277 {
1278         struct sta_info *sta_inf = container_of(sta, struct sta_info, sta);
1279         bool in_ps;
1280
1281         WARN_ON(!(sta_inf->local->hw.flags & IEEE80211_HW_AP_LINK_PS));
1282
1283         /* Don't let the same PS state be set twice */
1284         in_ps = test_sta_flag(sta_inf, WLAN_STA_PS_STA);
1285         if ((start && in_ps) || (!start && !in_ps))
1286                 return -EINVAL;
1287
1288         if (start)
1289                 sta_ps_start(sta_inf);
1290         else
1291                 sta_ps_end(sta_inf);
1292
1293         return 0;
1294 }
1295 EXPORT_SYMBOL(ieee80211_sta_ps_transition);
1296
1297 static ieee80211_rx_result debug_noinline
1298 ieee80211_rx_h_uapsd_and_pspoll(struct ieee80211_rx_data *rx)
1299 {
1300         struct ieee80211_sub_if_data *sdata = rx->sdata;
1301         struct ieee80211_hdr *hdr = (void *)rx->skb->data;
1302         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1303         int tid, ac;
1304
1305         if (!rx->sta || !(status->rx_flags & IEEE80211_RX_RA_MATCH))
1306                 return RX_CONTINUE;
1307
1308         if (sdata->vif.type != NL80211_IFTYPE_AP &&
1309             sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
1310                 return RX_CONTINUE;
1311
1312         /*
1313          * The device handles station powersave, so don't do anything about
1314          * uAPSD and PS-Poll frames (the latter shouldn't even come up from
1315          * it to mac80211 since they're handled.)
1316          */
1317         if (sdata->local->hw.flags & IEEE80211_HW_AP_LINK_PS)
1318                 return RX_CONTINUE;
1319
1320         /*
1321          * Don't do anything if the station isn't already asleep. In
1322          * the uAPSD case, the station will probably be marked asleep,
1323          * in the PS-Poll case the station must be confused ...
1324          */
1325         if (!test_sta_flag(rx->sta, WLAN_STA_PS_STA))
1326                 return RX_CONTINUE;
1327
1328         if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) {
1329                 if (!test_sta_flag(rx->sta, WLAN_STA_SP)) {
1330                         if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1331                                 ieee80211_sta_ps_deliver_poll_response(rx->sta);
1332                         else
1333                                 set_sta_flag(rx->sta, WLAN_STA_PSPOLL);
1334                 }
1335
1336                 /* Free PS Poll skb here instead of returning RX_DROP that would
1337                  * count as an dropped frame. */
1338                 dev_kfree_skb(rx->skb);
1339
1340                 return RX_QUEUED;
1341         } else if (!ieee80211_has_morefrags(hdr->frame_control) &&
1342                    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1343                    ieee80211_has_pm(hdr->frame_control) &&
1344                    (ieee80211_is_data_qos(hdr->frame_control) ||
1345                     ieee80211_is_qos_nullfunc(hdr->frame_control))) {
1346                 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
1347                 ac = ieee802_1d_to_ac[tid & 7];
1348
1349                 /*
1350                  * If this AC is not trigger-enabled do nothing.
1351                  *
1352                  * NB: This could/should check a separate bitmap of trigger-
1353                  * enabled queues, but for now we only implement uAPSD w/o
1354                  * TSPEC changes to the ACs, so they're always the same.
1355                  */
1356                 if (!(rx->sta->sta.uapsd_queues & BIT(ac)))
1357                         return RX_CONTINUE;
1358
1359                 /* if we are in a service period, do nothing */
1360                 if (test_sta_flag(rx->sta, WLAN_STA_SP))
1361                         return RX_CONTINUE;
1362
1363                 if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1364                         ieee80211_sta_ps_deliver_uapsd(rx->sta);
1365                 else
1366                         set_sta_flag(rx->sta, WLAN_STA_UAPSD);
1367         }
1368
1369         return RX_CONTINUE;
1370 }
1371
1372 static ieee80211_rx_result debug_noinline
1373 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1374 {
1375         struct sta_info *sta = rx->sta;
1376         struct sk_buff *skb = rx->skb;
1377         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1378         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1379         int i;
1380
1381         if (!sta)
1382                 return RX_CONTINUE;
1383
1384         /*
1385          * Update last_rx only for IBSS packets which are for the current
1386          * BSSID and for station already AUTHORIZED to avoid keeping the
1387          * current IBSS network alive in cases where other STAs start
1388          * using different BSSID. This will also give the station another
1389          * chance to restart the authentication/authorization in case
1390          * something went wrong the first time.
1391          */
1392         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1393                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1394                                                 NL80211_IFTYPE_ADHOC);
1395                 if (ether_addr_equal(bssid, rx->sdata->u.ibss.bssid) &&
1396                     test_sta_flag(sta, WLAN_STA_AUTHORIZED)) {
1397                         sta->last_rx = jiffies;
1398                         if (ieee80211_is_data(hdr->frame_control)) {
1399                                 sta->last_rx_rate_idx = status->rate_idx;
1400                                 sta->last_rx_rate_flag = status->flag;
1401                                 sta->last_rx_rate_vht_nss = status->vht_nss;
1402                         }
1403                 }
1404         } else if (!is_multicast_ether_addr(hdr->addr1)) {
1405                 /*
1406                  * Mesh beacons will update last_rx when if they are found to
1407                  * match the current local configuration when processed.
1408                  */
1409                 sta->last_rx = jiffies;
1410                 if (ieee80211_is_data(hdr->frame_control)) {
1411                         sta->last_rx_rate_idx = status->rate_idx;
1412                         sta->last_rx_rate_flag = status->flag;
1413                         sta->last_rx_rate_vht_nss = status->vht_nss;
1414                 }
1415         }
1416
1417         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1418                 return RX_CONTINUE;
1419
1420         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1421                 ieee80211_sta_rx_notify(rx->sdata, hdr);
1422
1423         sta->rx_fragments++;
1424         sta->rx_bytes += rx->skb->len;
1425         if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
1426                 sta->last_signal = status->signal;
1427                 ewma_add(&sta->avg_signal, -status->signal);
1428         }
1429
1430         if (status->chains) {
1431                 sta->chains = status->chains;
1432                 for (i = 0; i < ARRAY_SIZE(status->chain_signal); i++) {
1433                         int signal = status->chain_signal[i];
1434
1435                         if (!(status->chains & BIT(i)))
1436                                 continue;
1437
1438                         sta->chain_signal_last[i] = signal;
1439                         ewma_add(&sta->chain_signal_avg[i], -signal);
1440                 }
1441         }
1442
1443         /*
1444          * Change STA power saving mode only at the end of a frame
1445          * exchange sequence.
1446          */
1447         if (!(sta->local->hw.flags & IEEE80211_HW_AP_LINK_PS) &&
1448             !ieee80211_has_morefrags(hdr->frame_control) &&
1449             !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1450             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1451              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1452                 if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
1453                         /*
1454                          * Ignore doze->wake transitions that are
1455                          * indicated by non-data frames, the standard
1456                          * is unclear here, but for example going to
1457                          * PS mode and then scanning would cause a
1458                          * doze->wake transition for the probe request,
1459                          * and that is clearly undesirable.
1460                          */
1461                         if (ieee80211_is_data(hdr->frame_control) &&
1462                             !ieee80211_has_pm(hdr->frame_control))
1463                                 sta_ps_end(sta);
1464                 } else {
1465                         if (ieee80211_has_pm(hdr->frame_control))
1466                                 sta_ps_start(sta);
1467                 }
1468         }
1469
1470         /* mesh power save support */
1471         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
1472                 ieee80211_mps_rx_h_sta_process(sta, hdr);
1473
1474         /*
1475          * Drop (qos-)data::nullfunc frames silently, since they
1476          * are used only to control station power saving mode.
1477          */
1478         if (ieee80211_is_nullfunc(hdr->frame_control) ||
1479             ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1480                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1481
1482                 /*
1483                  * If we receive a 4-addr nullfunc frame from a STA
1484                  * that was not moved to a 4-addr STA vlan yet send
1485                  * the event to userspace and for older hostapd drop
1486                  * the frame to the monitor interface.
1487                  */
1488                 if (ieee80211_has_a4(hdr->frame_control) &&
1489                     (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1490                      (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1491                       !rx->sdata->u.vlan.sta))) {
1492                         if (!test_and_set_sta_flag(sta, WLAN_STA_4ADDR_EVENT))
1493                                 cfg80211_rx_unexpected_4addr_frame(
1494                                         rx->sdata->dev, sta->sta.addr,
1495                                         GFP_ATOMIC);
1496                         return RX_DROP_MONITOR;
1497                 }
1498                 /*
1499                  * Update counter and free packet here to avoid
1500                  * counting this as a dropped packed.
1501                  */
1502                 sta->rx_packets++;
1503                 dev_kfree_skb(rx->skb);
1504                 return RX_QUEUED;
1505         }
1506
1507         return RX_CONTINUE;
1508 } /* ieee80211_rx_h_sta_process */
1509
1510 static inline struct ieee80211_fragment_entry *
1511 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1512                          unsigned int frag, unsigned int seq, int rx_queue,
1513                          struct sk_buff **skb)
1514 {
1515         struct ieee80211_fragment_entry *entry;
1516
1517         entry = &sdata->fragments[sdata->fragment_next++];
1518         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1519                 sdata->fragment_next = 0;
1520
1521         if (!skb_queue_empty(&entry->skb_list))
1522                 __skb_queue_purge(&entry->skb_list);
1523
1524         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1525         *skb = NULL;
1526         entry->first_frag_time = jiffies;
1527         entry->seq = seq;
1528         entry->rx_queue = rx_queue;
1529         entry->last_frag = frag;
1530         entry->ccmp = 0;
1531         entry->extra_len = 0;
1532
1533         return entry;
1534 }
1535
1536 static inline struct ieee80211_fragment_entry *
1537 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1538                           unsigned int frag, unsigned int seq,
1539                           int rx_queue, struct ieee80211_hdr *hdr)
1540 {
1541         struct ieee80211_fragment_entry *entry;
1542         int i, idx;
1543
1544         idx = sdata->fragment_next;
1545         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1546                 struct ieee80211_hdr *f_hdr;
1547
1548                 idx--;
1549                 if (idx < 0)
1550                         idx = IEEE80211_FRAGMENT_MAX - 1;
1551
1552                 entry = &sdata->fragments[idx];
1553                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1554                     entry->rx_queue != rx_queue ||
1555                     entry->last_frag + 1 != frag)
1556                         continue;
1557
1558                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1559
1560                 /*
1561                  * Check ftype and addresses are equal, else check next fragment
1562                  */
1563                 if (((hdr->frame_control ^ f_hdr->frame_control) &
1564                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1565                     !ether_addr_equal(hdr->addr1, f_hdr->addr1) ||
1566                     !ether_addr_equal(hdr->addr2, f_hdr->addr2))
1567                         continue;
1568
1569                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1570                         __skb_queue_purge(&entry->skb_list);
1571                         continue;
1572                 }
1573                 return entry;
1574         }
1575
1576         return NULL;
1577 }
1578
1579 static ieee80211_rx_result debug_noinline
1580 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1581 {
1582         struct ieee80211_hdr *hdr;
1583         u16 sc;
1584         __le16 fc;
1585         unsigned int frag, seq;
1586         struct ieee80211_fragment_entry *entry;
1587         struct sk_buff *skb;
1588         struct ieee80211_rx_status *status;
1589
1590         hdr = (struct ieee80211_hdr *)rx->skb->data;
1591         fc = hdr->frame_control;
1592
1593         if (ieee80211_is_ctl(fc))
1594                 return RX_CONTINUE;
1595
1596         sc = le16_to_cpu(hdr->seq_ctrl);
1597         frag = sc & IEEE80211_SCTL_FRAG;
1598
1599         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1600                    is_multicast_ether_addr(hdr->addr1))) {
1601                 /* not fragmented */
1602                 goto out;
1603         }
1604         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1605
1606         if (skb_linearize(rx->skb))
1607                 return RX_DROP_UNUSABLE;
1608
1609         /*
1610          *  skb_linearize() might change the skb->data and
1611          *  previously cached variables (in this case, hdr) need to
1612          *  be refreshed with the new data.
1613          */
1614         hdr = (struct ieee80211_hdr *)rx->skb->data;
1615         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1616
1617         if (frag == 0) {
1618                 /* This is the first fragment of a new frame. */
1619                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1620                                                  rx->seqno_idx, &(rx->skb));
1621                 if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP &&
1622                     ieee80211_has_protected(fc)) {
1623                         int queue = rx->security_idx;
1624                         /* Store CCMP PN so that we can verify that the next
1625                          * fragment has a sequential PN value. */
1626                         entry->ccmp = 1;
1627                         memcpy(entry->last_pn,
1628                                rx->key->u.ccmp.rx_pn[queue],
1629                                IEEE80211_CCMP_PN_LEN);
1630                 }
1631                 return RX_QUEUED;
1632         }
1633
1634         /* This is a fragment for a frame that should already be pending in
1635          * fragment cache. Add this fragment to the end of the pending entry.
1636          */
1637         entry = ieee80211_reassemble_find(rx->sdata, frag, seq,
1638                                           rx->seqno_idx, hdr);
1639         if (!entry) {
1640                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1641                 return RX_DROP_MONITOR;
1642         }
1643
1644         /* Verify that MPDUs within one MSDU have sequential PN values.
1645          * (IEEE 802.11i, 8.3.3.4.5) */
1646         if (entry->ccmp) {
1647                 int i;
1648                 u8 pn[IEEE80211_CCMP_PN_LEN], *rpn;
1649                 int queue;
1650                 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP)
1651                         return RX_DROP_UNUSABLE;
1652                 memcpy(pn, entry->last_pn, IEEE80211_CCMP_PN_LEN);
1653                 for (i = IEEE80211_CCMP_PN_LEN - 1; i >= 0; i--) {
1654                         pn[i]++;
1655                         if (pn[i])
1656                                 break;
1657                 }
1658                 queue = rx->security_idx;
1659                 rpn = rx->key->u.ccmp.rx_pn[queue];
1660                 if (memcmp(pn, rpn, IEEE80211_CCMP_PN_LEN))
1661                         return RX_DROP_UNUSABLE;
1662                 memcpy(entry->last_pn, pn, IEEE80211_CCMP_PN_LEN);
1663         }
1664
1665         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1666         __skb_queue_tail(&entry->skb_list, rx->skb);
1667         entry->last_frag = frag;
1668         entry->extra_len += rx->skb->len;
1669         if (ieee80211_has_morefrags(fc)) {
1670                 rx->skb = NULL;
1671                 return RX_QUEUED;
1672         }
1673
1674         rx->skb = __skb_dequeue(&entry->skb_list);
1675         if (skb_tailroom(rx->skb) < entry->extra_len) {
1676                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1677                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1678                                               GFP_ATOMIC))) {
1679                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1680                         __skb_queue_purge(&entry->skb_list);
1681                         return RX_DROP_UNUSABLE;
1682                 }
1683         }
1684         while ((skb = __skb_dequeue(&entry->skb_list))) {
1685                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1686                 dev_kfree_skb(skb);
1687         }
1688
1689         /* Complete frame has been reassembled - process it now */
1690         status = IEEE80211_SKB_RXCB(rx->skb);
1691         status->rx_flags |= IEEE80211_RX_FRAGMENTED;
1692
1693  out:
1694         if (rx->sta)
1695                 rx->sta->rx_packets++;
1696         if (is_multicast_ether_addr(hdr->addr1))
1697                 rx->local->dot11MulticastReceivedFrameCount++;
1698         else
1699                 ieee80211_led_rx(rx->local);
1700         return RX_CONTINUE;
1701 }
1702
1703 static int ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1704 {
1705         if (unlikely(!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_AUTHORIZED)))
1706                 return -EACCES;
1707
1708         return 0;
1709 }
1710
1711 static int ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1712 {
1713         struct sk_buff *skb = rx->skb;
1714         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1715
1716         /*
1717          * Pass through unencrypted frames if the hardware has
1718          * decrypted them already.
1719          */
1720         if (status->flag & RX_FLAG_DECRYPTED)
1721                 return 0;
1722
1723         /* Drop unencrypted frames if key is set. */
1724         if (unlikely(!ieee80211_has_protected(fc) &&
1725                      !ieee80211_is_nullfunc(fc) &&
1726                      ieee80211_is_data(fc) &&
1727                      (rx->key || rx->sdata->drop_unencrypted)))
1728                 return -EACCES;
1729
1730         return 0;
1731 }
1732
1733 static int ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1734 {
1735         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1736         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1737         __le16 fc = hdr->frame_control;
1738
1739         /*
1740          * Pass through unencrypted frames if the hardware has
1741          * decrypted them already.
1742          */
1743         if (status->flag & RX_FLAG_DECRYPTED)
1744                 return 0;
1745
1746         if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) {
1747                 if (unlikely(!ieee80211_has_protected(fc) &&
1748                              ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1749                              rx->key)) {
1750                         if (ieee80211_is_deauth(fc) ||
1751                             ieee80211_is_disassoc(fc))
1752                                 cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
1753                                                              rx->skb->data,
1754                                                              rx->skb->len);
1755                         return -EACCES;
1756                 }
1757                 /* BIP does not use Protected field, so need to check MMIE */
1758                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1759                              ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
1760                         if (ieee80211_is_deauth(fc) ||
1761                             ieee80211_is_disassoc(fc))
1762                                 cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
1763                                                              rx->skb->data,
1764                                                              rx->skb->len);
1765                         return -EACCES;
1766                 }
1767                 /*
1768                  * When using MFP, Action frames are not allowed prior to
1769                  * having configured keys.
1770                  */
1771                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1772                              ieee80211_is_robust_mgmt_frame(
1773                                      (struct ieee80211_hdr *) rx->skb->data)))
1774                         return -EACCES;
1775         }
1776
1777         return 0;
1778 }
1779
1780 static int
1781 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx, bool *port_control)
1782 {
1783         struct ieee80211_sub_if_data *sdata = rx->sdata;
1784         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1785         bool check_port_control = false;
1786         struct ethhdr *ehdr;
1787         int ret;
1788
1789         *port_control = false;
1790         if (ieee80211_has_a4(hdr->frame_control) &&
1791             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1792                 return -1;
1793
1794         if (sdata->vif.type == NL80211_IFTYPE_STATION &&
1795             !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) {
1796
1797                 if (!sdata->u.mgd.use_4addr)
1798                         return -1;
1799                 else
1800                         check_port_control = true;
1801         }
1802
1803         if (is_multicast_ether_addr(hdr->addr1) &&
1804             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta)
1805                 return -1;
1806
1807         ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1808         if (ret < 0)
1809                 return ret;
1810
1811         ehdr = (struct ethhdr *) rx->skb->data;
1812         if (ehdr->h_proto == rx->sdata->control_port_protocol)
1813                 *port_control = true;
1814         else if (check_port_control)
1815                 return -1;
1816
1817         return 0;
1818 }
1819
1820 /*
1821  * requires that rx->skb is a frame with ethernet header
1822  */
1823 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1824 {
1825         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1826                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1827         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1828
1829         /*
1830          * Allow EAPOL frames to us/the PAE group address regardless
1831          * of whether the frame was encrypted or not.
1832          */
1833         if (ehdr->h_proto == rx->sdata->control_port_protocol &&
1834             (ether_addr_equal(ehdr->h_dest, rx->sdata->vif.addr) ||
1835              ether_addr_equal(ehdr->h_dest, pae_group_addr)))
1836                 return true;
1837
1838         if (ieee80211_802_1x_port_control(rx) ||
1839             ieee80211_drop_unencrypted(rx, fc))
1840                 return false;
1841
1842         return true;
1843 }
1844
1845 /*
1846  * requires that rx->skb is a frame with ethernet header
1847  */
1848 static void
1849 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1850 {
1851         struct ieee80211_sub_if_data *sdata = rx->sdata;
1852         struct net_device *dev = sdata->dev;
1853         struct sk_buff *skb, *xmit_skb;
1854         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1855         struct sta_info *dsta;
1856         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1857
1858         skb = rx->skb;
1859         xmit_skb = NULL;
1860
1861         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1862              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1863             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1864             (status->rx_flags & IEEE80211_RX_RA_MATCH) &&
1865             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1866                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1867                         /*
1868                          * send multicast frames both to higher layers in
1869                          * local net stack and back to the wireless medium
1870                          */
1871                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1872                         if (!xmit_skb)
1873                                 net_info_ratelimited("%s: failed to clone multicast frame\n",
1874                                                     dev->name);
1875                 } else {
1876                         dsta = sta_info_get(sdata, skb->data);
1877                         if (dsta) {
1878                                 /*
1879                                  * The destination station is associated to
1880                                  * this AP (in this VLAN), so send the frame
1881                                  * directly to it and do not pass it to local
1882                                  * net stack.
1883                                  */
1884                                 xmit_skb = skb;
1885                                 skb = NULL;
1886                         }
1887                 }
1888         }
1889
1890         if (skb) {
1891                 int align __maybe_unused;
1892
1893 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1894                 /*
1895                  * 'align' will only take the values 0 or 2 here
1896                  * since all frames are required to be aligned
1897                  * to 2-byte boundaries when being passed to
1898                  * mac80211; the code here works just as well if
1899                  * that isn't true, but mac80211 assumes it can
1900                  * access fields as 2-byte aligned (e.g. for
1901                  * compare_ether_addr)
1902                  */
1903                 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1904                 if (align) {
1905                         if (WARN_ON(skb_headroom(skb) < 3)) {
1906                                 dev_kfree_skb(skb);
1907                                 skb = NULL;
1908                         } else {
1909                                 u8 *data = skb->data;
1910                                 size_t len = skb_headlen(skb);
1911                                 skb->data -= align;
1912                                 memmove(skb->data, data, len);
1913                                 skb_set_tail_pointer(skb, len);
1914                         }
1915                 }
1916 #endif
1917
1918                 if (skb) {
1919                         /* deliver to local stack */
1920                         skb->protocol = eth_type_trans(skb, dev);
1921                         memset(skb->cb, 0, sizeof(skb->cb));
1922                         netif_receive_skb(skb);
1923                 }
1924         }
1925
1926         if (xmit_skb) {
1927                 /*
1928                  * Send to wireless media and increase priority by 256 to
1929                  * keep the received priority instead of reclassifying
1930                  * the frame (see cfg80211_classify8021d).
1931                  */
1932                 xmit_skb->priority += 256;
1933                 xmit_skb->protocol = htons(ETH_P_802_3);
1934                 skb_reset_network_header(xmit_skb);
1935                 skb_reset_mac_header(xmit_skb);
1936                 dev_queue_xmit(xmit_skb);
1937         }
1938 }
1939
1940 static ieee80211_rx_result debug_noinline
1941 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1942 {
1943         struct net_device *dev = rx->sdata->dev;
1944         struct sk_buff *skb = rx->skb;
1945         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1946         __le16 fc = hdr->frame_control;
1947         struct sk_buff_head frame_list;
1948         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1949
1950         if (unlikely(!ieee80211_is_data(fc)))
1951                 return RX_CONTINUE;
1952
1953         if (unlikely(!ieee80211_is_data_present(fc)))
1954                 return RX_DROP_MONITOR;
1955
1956         if (!(status->rx_flags & IEEE80211_RX_AMSDU))
1957                 return RX_CONTINUE;
1958
1959         if (ieee80211_has_a4(hdr->frame_control) &&
1960             rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1961             !rx->sdata->u.vlan.sta)
1962                 return RX_DROP_UNUSABLE;
1963
1964         if (is_multicast_ether_addr(hdr->addr1) &&
1965             ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1966               rx->sdata->u.vlan.sta) ||
1967              (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1968               rx->sdata->u.mgd.use_4addr)))
1969                 return RX_DROP_UNUSABLE;
1970
1971         skb->dev = dev;
1972         __skb_queue_head_init(&frame_list);
1973
1974         if (skb_linearize(skb))
1975                 return RX_DROP_UNUSABLE;
1976
1977         ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1978                                  rx->sdata->vif.type,
1979                                  rx->local->hw.extra_tx_headroom, true);
1980
1981         while (!skb_queue_empty(&frame_list)) {
1982                 rx->skb = __skb_dequeue(&frame_list);
1983
1984                 if (!ieee80211_frame_allowed(rx, fc)) {
1985                         dev_kfree_skb(rx->skb);
1986                         continue;
1987                 }
1988                 dev->stats.rx_packets++;
1989                 dev->stats.rx_bytes += rx->skb->len;
1990
1991                 ieee80211_deliver_skb(rx);
1992         }
1993
1994         return RX_QUEUED;
1995 }
1996
1997 #ifdef CONFIG_MAC80211_MESH
1998 static ieee80211_rx_result
1999 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
2000 {
2001         struct ieee80211_hdr *fwd_hdr, *hdr;
2002         struct ieee80211_tx_info *info;
2003         struct ieee80211s_hdr *mesh_hdr;
2004         struct sk_buff *skb = rx->skb, *fwd_skb;
2005         struct ieee80211_local *local = rx->local;
2006         struct ieee80211_sub_if_data *sdata = rx->sdata;
2007         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2008         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
2009         __le16 reason = cpu_to_le16(WLAN_REASON_MESH_PATH_NOFORWARD);
2010         u16 q, hdrlen;
2011
2012         hdr = (struct ieee80211_hdr *) skb->data;
2013         hdrlen = ieee80211_hdrlen(hdr->frame_control);
2014
2015         /* make sure fixed part of mesh header is there, also checks skb len */
2016         if (!pskb_may_pull(rx->skb, hdrlen + 6))
2017                 return RX_DROP_MONITOR;
2018
2019         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2020
2021         /* make sure full mesh header is there, also checks skb len */
2022         if (!pskb_may_pull(rx->skb,
2023                            hdrlen + ieee80211_get_mesh_hdrlen(mesh_hdr)))
2024                 return RX_DROP_MONITOR;
2025
2026         /* reload pointers */
2027         hdr = (struct ieee80211_hdr *) skb->data;
2028         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2029
2030         /* frame is in RMC, don't forward */
2031         if (ieee80211_is_data(hdr->frame_control) &&
2032             is_multicast_ether_addr(hdr->addr1) &&
2033             mesh_rmc_check(rx->sdata, hdr->addr3, mesh_hdr))
2034                 return RX_DROP_MONITOR;
2035
2036         if (!ieee80211_is_data(hdr->frame_control) ||
2037             !(status->rx_flags & IEEE80211_RX_RA_MATCH))
2038                 return RX_CONTINUE;
2039
2040         if (!mesh_hdr->ttl)
2041                 return RX_DROP_MONITOR;
2042
2043         if (mesh_hdr->flags & MESH_FLAGS_AE) {
2044                 struct mesh_path *mppath;
2045                 char *proxied_addr;
2046                 char *mpp_addr;
2047
2048                 if (is_multicast_ether_addr(hdr->addr1)) {
2049                         mpp_addr = hdr->addr3;
2050                         proxied_addr = mesh_hdr->eaddr1;
2051                 } else if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6) {
2052                         /* has_a4 already checked in ieee80211_rx_mesh_check */
2053                         mpp_addr = hdr->addr4;
2054                         proxied_addr = mesh_hdr->eaddr2;
2055                 } else {
2056                         return RX_DROP_MONITOR;
2057                 }
2058
2059                 rcu_read_lock();
2060                 mppath = mpp_path_lookup(sdata, proxied_addr);
2061                 if (!mppath) {
2062                         mpp_path_add(sdata, proxied_addr, mpp_addr);
2063                 } else {
2064                         spin_lock_bh(&mppath->state_lock);
2065                         if (!ether_addr_equal(mppath->mpp, mpp_addr))
2066                                 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
2067                         spin_unlock_bh(&mppath->state_lock);
2068                 }
2069                 rcu_read_unlock();
2070         }
2071
2072         /* Frame has reached destination.  Don't forward */
2073         if (!is_multicast_ether_addr(hdr->addr1) &&
2074             ether_addr_equal(sdata->vif.addr, hdr->addr3))
2075                 return RX_CONTINUE;
2076
2077         q = ieee80211_select_queue_80211(sdata, skb, hdr);
2078         if (ieee80211_queue_stopped(&local->hw, q)) {
2079                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion);
2080                 return RX_DROP_MONITOR;
2081         }
2082         skb_set_queue_mapping(skb, q);
2083
2084         if (!--mesh_hdr->ttl) {
2085                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
2086                 goto out;
2087         }
2088
2089         if (!ifmsh->mshcfg.dot11MeshForwarding)
2090                 goto out;
2091
2092         fwd_skb = skb_copy(skb, GFP_ATOMIC);
2093         if (!fwd_skb) {
2094                 net_info_ratelimited("%s: failed to clone mesh frame\n",
2095                                     sdata->name);
2096                 goto out;
2097         }
2098
2099         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
2100         fwd_hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_RETRY);
2101         info = IEEE80211_SKB_CB(fwd_skb);
2102         memset(info, 0, sizeof(*info));
2103         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
2104         info->control.vif = &rx->sdata->vif;
2105         info->control.jiffies = jiffies;
2106         if (is_multicast_ether_addr(fwd_hdr->addr1)) {
2107                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_mcast);
2108                 memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
2109                 /* update power mode indication when forwarding */
2110                 ieee80211_mps_set_frame_flags(sdata, NULL, fwd_hdr);
2111         } else if (!mesh_nexthop_lookup(sdata, fwd_skb)) {
2112                 /* mesh power mode flags updated in mesh_nexthop_lookup */
2113                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_unicast);
2114         } else {
2115                 /* unable to resolve next hop */
2116                 mesh_path_error_tx(sdata, ifmsh->mshcfg.element_ttl,
2117                                    fwd_hdr->addr3, 0, reason, fwd_hdr->addr2);
2118                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_no_route);
2119                 kfree_skb(fwd_skb);
2120                 return RX_DROP_MONITOR;
2121         }
2122
2123         IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_frames);
2124         ieee80211_add_pending_skb(local, fwd_skb);
2125  out:
2126         if (is_multicast_ether_addr(hdr->addr1) ||
2127             sdata->dev->flags & IFF_PROMISC)
2128                 return RX_CONTINUE;
2129         else
2130                 return RX_DROP_MONITOR;
2131 }
2132 #endif
2133
2134 static ieee80211_rx_result debug_noinline
2135 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
2136 {
2137         struct ieee80211_sub_if_data *sdata = rx->sdata;
2138         struct ieee80211_local *local = rx->local;
2139         struct net_device *dev = sdata->dev;
2140         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2141         __le16 fc = hdr->frame_control;
2142         bool port_control;
2143         int err;
2144
2145         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
2146                 return RX_CONTINUE;
2147
2148         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
2149                 return RX_DROP_MONITOR;
2150
2151         /*
2152          * Send unexpected-4addr-frame event to hostapd. For older versions,
2153          * also drop the frame to cooked monitor interfaces.
2154          */
2155         if (ieee80211_has_a4(hdr->frame_control) &&
2156             sdata->vif.type == NL80211_IFTYPE_AP) {
2157                 if (rx->sta &&
2158                     !test_and_set_sta_flag(rx->sta, WLAN_STA_4ADDR_EVENT))
2159                         cfg80211_rx_unexpected_4addr_frame(
2160                                 rx->sdata->dev, rx->sta->sta.addr, GFP_ATOMIC);
2161                 return RX_DROP_MONITOR;
2162         }
2163
2164         err = __ieee80211_data_to_8023(rx, &port_control);
2165         if (unlikely(err))
2166                 return RX_DROP_UNUSABLE;
2167
2168         if (!ieee80211_frame_allowed(rx, fc))
2169                 return RX_DROP_MONITOR;
2170
2171         if (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
2172             unlikely(port_control) && sdata->bss) {
2173                 sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
2174                                      u.ap);
2175                 dev = sdata->dev;
2176                 rx->sdata = sdata;
2177         }
2178
2179         rx->skb->dev = dev;
2180
2181         dev->stats.rx_packets++;
2182         dev->stats.rx_bytes += rx->skb->len;
2183
2184         if (local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
2185             !is_multicast_ether_addr(
2186                     ((struct ethhdr *)rx->skb->data)->h_dest) &&
2187             (!local->scanning &&
2188              !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state))) {
2189                         mod_timer(&local->dynamic_ps_timer, jiffies +
2190                          msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
2191         }
2192
2193         ieee80211_deliver_skb(rx);
2194
2195         return RX_QUEUED;
2196 }
2197
2198 static ieee80211_rx_result debug_noinline
2199 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
2200 {
2201         struct sk_buff *skb = rx->skb;
2202         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
2203         struct tid_ampdu_rx *tid_agg_rx;
2204         u16 start_seq_num;
2205         u16 tid;
2206
2207         if (likely(!ieee80211_is_ctl(bar->frame_control)))
2208                 return RX_CONTINUE;
2209
2210         if (ieee80211_is_back_req(bar->frame_control)) {
2211                 struct {
2212                         __le16 control, start_seq_num;
2213                 } __packed bar_data;
2214
2215                 if (!rx->sta)
2216                         return RX_DROP_MONITOR;
2217
2218                 if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
2219                                   &bar_data, sizeof(bar_data)))
2220                         return RX_DROP_MONITOR;
2221
2222                 tid = le16_to_cpu(bar_data.control) >> 12;
2223
2224                 tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
2225                 if (!tid_agg_rx)
2226                         return RX_DROP_MONITOR;
2227
2228                 start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
2229
2230                 /* reset session timer */
2231                 if (tid_agg_rx->timeout)
2232                         mod_timer(&tid_agg_rx->session_timer,
2233                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
2234
2235                 spin_lock(&tid_agg_rx->reorder_lock);
2236                 /* release stored frames up to start of BAR */
2237                 ieee80211_release_reorder_frames(rx->sdata, tid_agg_rx,
2238                                                  start_seq_num, frames);
2239                 spin_unlock(&tid_agg_rx->reorder_lock);
2240
2241                 kfree_skb(skb);
2242                 return RX_QUEUED;
2243         }
2244
2245         /*
2246          * After this point, we only want management frames,
2247          * so we can drop all remaining control frames to
2248          * cooked monitor interfaces.
2249          */
2250         return RX_DROP_MONITOR;
2251 }
2252
2253 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
2254                                            struct ieee80211_mgmt *mgmt,
2255                                            size_t len)
2256 {
2257         struct ieee80211_local *local = sdata->local;
2258         struct sk_buff *skb;
2259         struct ieee80211_mgmt *resp;
2260
2261         if (!ether_addr_equal(mgmt->da, sdata->vif.addr)) {
2262                 /* Not to own unicast address */
2263                 return;
2264         }
2265
2266         if (!ether_addr_equal(mgmt->sa, sdata->u.mgd.bssid) ||
2267             !ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid)) {
2268                 /* Not from the current AP or not associated yet. */
2269                 return;
2270         }
2271
2272         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
2273                 /* Too short SA Query request frame */
2274                 return;
2275         }
2276
2277         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
2278         if (skb == NULL)
2279                 return;
2280
2281         skb_reserve(skb, local->hw.extra_tx_headroom);
2282         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
2283         memset(resp, 0, 24);
2284         memcpy(resp->da, mgmt->sa, ETH_ALEN);
2285         memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
2286         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
2287         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2288                                           IEEE80211_STYPE_ACTION);
2289         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
2290         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
2291         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
2292         memcpy(resp->u.action.u.sa_query.trans_id,
2293                mgmt->u.action.u.sa_query.trans_id,
2294                WLAN_SA_QUERY_TR_ID_LEN);
2295
2296         ieee80211_tx_skb(sdata, skb);
2297 }
2298
2299 static ieee80211_rx_result debug_noinline
2300 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
2301 {
2302         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2303         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2304
2305         /*
2306          * From here on, look only at management frames.
2307          * Data and control frames are already handled,
2308          * and unknown (reserved) frames are useless.
2309          */
2310         if (rx->skb->len < 24)
2311                 return RX_DROP_MONITOR;
2312
2313         if (!ieee80211_is_mgmt(mgmt->frame_control))
2314                 return RX_DROP_MONITOR;
2315
2316         if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
2317             ieee80211_is_beacon(mgmt->frame_control) &&
2318             !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) {
2319                 int sig = 0;
2320
2321                 if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2322                         sig = status->signal;
2323
2324                 cfg80211_report_obss_beacon(rx->local->hw.wiphy,
2325                                             rx->skb->data, rx->skb->len,
2326                                             status->freq, sig);
2327                 rx->flags |= IEEE80211_RX_BEACON_REPORTED;
2328         }
2329
2330         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2331                 return RX_DROP_MONITOR;
2332
2333         if (ieee80211_drop_unencrypted_mgmt(rx))
2334                 return RX_DROP_UNUSABLE;
2335
2336         return RX_CONTINUE;
2337 }
2338
2339 static ieee80211_rx_result debug_noinline
2340 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2341 {
2342         struct ieee80211_local *local = rx->local;
2343         struct ieee80211_sub_if_data *sdata = rx->sdata;
2344         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2345         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2346         int len = rx->skb->len;
2347
2348         if (!ieee80211_is_action(mgmt->frame_control))
2349                 return RX_CONTINUE;
2350
2351         /* drop too small frames */
2352         if (len < IEEE80211_MIN_ACTION_SIZE)
2353                 return RX_DROP_UNUSABLE;
2354
2355         if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC &&
2356             mgmt->u.action.category != WLAN_CATEGORY_SELF_PROTECTED)
2357                 return RX_DROP_UNUSABLE;
2358
2359         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2360                 return RX_DROP_UNUSABLE;
2361
2362         switch (mgmt->u.action.category) {
2363         case WLAN_CATEGORY_HT:
2364                 /* reject HT action frames from stations not supporting HT */
2365                 if (!rx->sta->sta.ht_cap.ht_supported)
2366                         goto invalid;
2367
2368                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2369                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2370                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2371                     sdata->vif.type != NL80211_IFTYPE_AP &&
2372                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2373                         break;
2374
2375                 /* verify action & smps_control/chanwidth are present */
2376                 if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2377                         goto invalid;
2378
2379                 switch (mgmt->u.action.u.ht_smps.action) {
2380                 case WLAN_HT_ACTION_SMPS: {
2381                         struct ieee80211_supported_band *sband;
2382                         enum ieee80211_smps_mode smps_mode;
2383
2384                         /* convert to HT capability */
2385                         switch (mgmt->u.action.u.ht_smps.smps_control) {
2386                         case WLAN_HT_SMPS_CONTROL_DISABLED:
2387                                 smps_mode = IEEE80211_SMPS_OFF;
2388                                 break;
2389                         case WLAN_HT_SMPS_CONTROL_STATIC:
2390                                 smps_mode = IEEE80211_SMPS_STATIC;
2391                                 break;
2392                         case WLAN_HT_SMPS_CONTROL_DYNAMIC:
2393                                 smps_mode = IEEE80211_SMPS_DYNAMIC;
2394                                 break;
2395                         default:
2396                                 goto invalid;
2397                         }
2398
2399                         /* if no change do nothing */
2400                         if (rx->sta->sta.smps_mode == smps_mode)
2401                                 goto handled;
2402                         rx->sta->sta.smps_mode = smps_mode;
2403
2404                         sband = rx->local->hw.wiphy->bands[status->band];
2405
2406                         rate_control_rate_update(local, sband, rx->sta,
2407                                                  IEEE80211_RC_SMPS_CHANGED);
2408                         goto handled;
2409                 }
2410                 case WLAN_HT_ACTION_NOTIFY_CHANWIDTH: {
2411                         struct ieee80211_supported_band *sband;
2412                         u8 chanwidth = mgmt->u.action.u.ht_notify_cw.chanwidth;
2413                         enum ieee80211_sta_rx_bandwidth new_bw;
2414
2415                         /* If it doesn't support 40 MHz it can't change ... */
2416                         if (!(rx->sta->sta.ht_cap.cap &
2417                                         IEEE80211_HT_CAP_SUP_WIDTH_20_40))
2418                                 goto handled;
2419
2420                         if (chanwidth == IEEE80211_HT_CHANWIDTH_20MHZ)
2421                                 new_bw = IEEE80211_STA_RX_BW_20;
2422                         else
2423                                 new_bw = ieee80211_sta_cur_vht_bw(rx->sta);
2424
2425                         if (rx->sta->sta.bandwidth == new_bw)
2426                                 goto handled;
2427
2428                         sband = rx->local->hw.wiphy->bands[status->band];
2429
2430                         rate_control_rate_update(local, sband, rx->sta,
2431                                                  IEEE80211_RC_BW_CHANGED);
2432                         goto handled;
2433                 }
2434                 default:
2435                         goto invalid;
2436                 }
2437
2438                 break;
2439         case WLAN_CATEGORY_PUBLIC:
2440                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2441                         goto invalid;
2442                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2443                         break;
2444                 if (!rx->sta)
2445                         break;
2446                 if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
2447                         break;
2448                 if (mgmt->u.action.u.ext_chan_switch.action_code !=
2449                                 WLAN_PUB_ACTION_EXT_CHANSW_ANN)
2450                         break;
2451                 if (len < offsetof(struct ieee80211_mgmt,
2452                                    u.action.u.ext_chan_switch.variable))
2453                         goto invalid;
2454                 goto queue;
2455         case WLAN_CATEGORY_VHT:
2456                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2457                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2458                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2459                     sdata->vif.type != NL80211_IFTYPE_AP &&
2460                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2461                         break;
2462
2463                 /* verify action code is present */
2464                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2465                         goto invalid;
2466
2467                 switch (mgmt->u.action.u.vht_opmode_notif.action_code) {
2468                 case WLAN_VHT_ACTION_OPMODE_NOTIF: {
2469                         u8 opmode;
2470
2471                         /* verify opmode is present */
2472                         if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2473                                 goto invalid;
2474
2475                         opmode = mgmt->u.action.u.vht_opmode_notif.operating_mode;
2476
2477                         ieee80211_vht_handle_opmode(rx->sdata, rx->sta,
2478                                                     opmode, status->band,
2479                                                     false);
2480                         goto handled;
2481                 }
2482                 default:
2483                         break;
2484                 }
2485                 break;
2486         case WLAN_CATEGORY_BACK:
2487                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2488                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2489                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2490                     sdata->vif.type != NL80211_IFTYPE_AP &&
2491                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2492                         break;
2493
2494                 /* verify action_code is present */
2495                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2496                         break;
2497
2498                 switch (mgmt->u.action.u.addba_req.action_code) {
2499                 case WLAN_ACTION_ADDBA_REQ:
2500                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2501                                    sizeof(mgmt->u.action.u.addba_req)))
2502                                 goto invalid;
2503                         break;
2504                 case WLAN_ACTION_ADDBA_RESP:
2505                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2506                                    sizeof(mgmt->u.action.u.addba_resp)))
2507                                 goto invalid;
2508                         break;
2509                 case WLAN_ACTION_DELBA:
2510                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2511                                    sizeof(mgmt->u.action.u.delba)))
2512                                 goto invalid;
2513                         break;
2514                 default:
2515                         goto invalid;
2516                 }
2517
2518                 goto queue;
2519         case WLAN_CATEGORY_SPECTRUM_MGMT:
2520                 if (status->band != IEEE80211_BAND_5GHZ)
2521                         break;
2522
2523                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2524                         break;
2525
2526                 /* verify action_code is present */
2527                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2528                         break;
2529
2530                 switch (mgmt->u.action.u.measurement.action_code) {
2531                 case WLAN_ACTION_SPCT_MSR_REQ:
2532                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2533                                    sizeof(mgmt->u.action.u.measurement)))
2534                                 break;
2535                         ieee80211_process_measurement_req(sdata, mgmt, len);
2536                         goto handled;
2537                 case WLAN_ACTION_SPCT_CHL_SWITCH:
2538                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2539                                 break;
2540
2541                         if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
2542                                 break;
2543
2544                         goto queue;
2545                 }
2546                 break;
2547         case WLAN_CATEGORY_SA_QUERY:
2548                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2549                            sizeof(mgmt->u.action.u.sa_query)))
2550                         break;
2551
2552                 switch (mgmt->u.action.u.sa_query.action) {
2553                 case WLAN_ACTION_SA_QUERY_REQUEST:
2554                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2555                                 break;
2556                         ieee80211_process_sa_query_req(sdata, mgmt, len);
2557                         goto handled;
2558                 }
2559                 break;
2560         case WLAN_CATEGORY_SELF_PROTECTED:
2561                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2562                            sizeof(mgmt->u.action.u.self_prot.action_code)))
2563                         break;
2564
2565                 switch (mgmt->u.action.u.self_prot.action_code) {
2566                 case WLAN_SP_MESH_PEERING_OPEN:
2567                 case WLAN_SP_MESH_PEERING_CLOSE:
2568                 case WLAN_SP_MESH_PEERING_CONFIRM:
2569                         if (!ieee80211_vif_is_mesh(&sdata->vif))
2570                                 goto invalid;
2571                         if (sdata->u.mesh.user_mpm)
2572                                 /* userspace handles this frame */
2573                                 break;
2574                         goto queue;
2575                 case WLAN_SP_MGK_INFORM:
2576                 case WLAN_SP_MGK_ACK:
2577                         if (!ieee80211_vif_is_mesh(&sdata->vif))
2578                                 goto invalid;
2579                         break;
2580                 }
2581                 break;
2582         case WLAN_CATEGORY_MESH_ACTION:
2583                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2584                            sizeof(mgmt->u.action.u.mesh_action.action_code)))
2585                         break;
2586
2587                 if (!ieee80211_vif_is_mesh(&sdata->vif))
2588                         break;
2589                 if (mesh_action_is_path_sel(mgmt) &&
2590                     !mesh_path_sel_is_hwmp(sdata))
2591                         break;
2592                 goto queue;
2593         }
2594
2595         return RX_CONTINUE;
2596
2597  invalid:
2598         status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
2599         /* will return in the next handlers */
2600         return RX_CONTINUE;
2601
2602  handled:
2603         if (rx->sta)
2604                 rx->sta->rx_packets++;
2605         dev_kfree_skb(rx->skb);
2606         return RX_QUEUED;
2607
2608  queue:
2609         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2610         skb_queue_tail(&sdata->skb_queue, rx->skb);
2611         ieee80211_queue_work(&local->hw, &sdata->work);
2612         if (rx->sta)
2613                 rx->sta->rx_packets++;
2614         return RX_QUEUED;
2615 }
2616
2617 static ieee80211_rx_result debug_noinline
2618 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
2619 {
2620         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2621         int sig = 0;
2622
2623         /* skip known-bad action frames and return them in the next handler */
2624         if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
2625                 return RX_CONTINUE;
2626
2627         /*
2628          * Getting here means the kernel doesn't know how to handle
2629          * it, but maybe userspace does ... include returned frames
2630          * so userspace can register for those to know whether ones
2631          * it transmitted were processed or returned.
2632          */
2633
2634         if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2635                 sig = status->signal;
2636
2637         if (cfg80211_rx_mgmt(&rx->sdata->wdev, status->freq, sig,
2638                              rx->skb->data, rx->skb->len,
2639                              GFP_ATOMIC)) {
2640                 if (rx->sta)
2641                         rx->sta->rx_packets++;
2642                 dev_kfree_skb(rx->skb);
2643                 return RX_QUEUED;
2644         }
2645
2646         return RX_CONTINUE;
2647 }
2648
2649 static ieee80211_rx_result debug_noinline
2650 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
2651 {
2652         struct ieee80211_local *local = rx->local;
2653         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2654         struct sk_buff *nskb;
2655         struct ieee80211_sub_if_data *sdata = rx->sdata;
2656         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2657
2658         if (!ieee80211_is_action(mgmt->frame_control))
2659                 return RX_CONTINUE;
2660
2661         /*
2662          * For AP mode, hostapd is responsible for handling any action
2663          * frames that we didn't handle, including returning unknown
2664          * ones. For all other modes we will return them to the sender,
2665          * setting the 0x80 bit in the action category, as required by
2666          * 802.11-2012 9.24.4.
2667          * Newer versions of hostapd shall also use the management frame
2668          * registration mechanisms, but older ones still use cooked
2669          * monitor interfaces so push all frames there.
2670          */
2671         if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
2672             (sdata->vif.type == NL80211_IFTYPE_AP ||
2673              sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
2674                 return RX_DROP_MONITOR;
2675
2676         if (is_multicast_ether_addr(mgmt->da))
2677                 return RX_DROP_MONITOR;
2678
2679         /* do not return rejected action frames */
2680         if (mgmt->u.action.category & 0x80)
2681                 return RX_DROP_UNUSABLE;
2682
2683         nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2684                                GFP_ATOMIC);
2685         if (nskb) {
2686                 struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
2687
2688                 nmgmt->u.action.category |= 0x80;
2689                 memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
2690                 memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2691
2692                 memset(nskb->cb, 0, sizeof(nskb->cb));
2693
2694                 if (rx->sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE) {
2695                         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(nskb);
2696
2697                         info->flags = IEEE80211_TX_CTL_TX_OFFCHAN |
2698                                       IEEE80211_TX_INTFL_OFFCHAN_TX_OK |
2699                                       IEEE80211_TX_CTL_NO_CCK_RATE;
2700                         if (local->hw.flags & IEEE80211_HW_QUEUE_CONTROL)
2701                                 info->hw_queue =
2702                                         local->hw.offchannel_tx_hw_queue;
2703                 }
2704
2705                 __ieee80211_tx_skb_tid_band(rx->sdata, nskb, 7,
2706                                             status->band);
2707         }
2708         dev_kfree_skb(rx->skb);
2709         return RX_QUEUED;
2710 }
2711
2712 static ieee80211_rx_result debug_noinline
2713 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2714 {
2715         struct ieee80211_sub_if_data *sdata = rx->sdata;
2716         struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2717         __le16 stype;
2718
2719         stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2720
2721         if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2722             sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2723             sdata->vif.type != NL80211_IFTYPE_STATION)
2724                 return RX_DROP_MONITOR;
2725
2726         switch (stype) {
2727         case cpu_to_le16(IEEE80211_STYPE_AUTH):
2728         case cpu_to_le16(IEEE80211_STYPE_BEACON):
2729         case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2730                 /* process for all: mesh, mlme, ibss */
2731                 break;
2732         case cpu_to_le16(IEEE80211_STYPE_ASSOC_RESP):
2733         case cpu_to_le16(IEEE80211_STYPE_REASSOC_RESP):
2734         case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2735         case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2736                 if (is_multicast_ether_addr(mgmt->da) &&
2737                     !is_broadcast_ether_addr(mgmt->da))
2738                         return RX_DROP_MONITOR;
2739
2740                 /* process only for station */
2741                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2742                         return RX_DROP_MONITOR;
2743                 break;
2744         case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2745                 /* process only for ibss and mesh */
2746                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2747                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT)
2748                         return RX_DROP_MONITOR;
2749                 break;
2750         default:
2751                 return RX_DROP_MONITOR;
2752         }
2753
2754         /* queue up frame and kick off work to process it */
2755         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2756         skb_queue_tail(&sdata->skb_queue, rx->skb);
2757         ieee80211_queue_work(&rx->local->hw, &sdata->work);
2758         if (rx->sta)
2759                 rx->sta->rx_packets++;
2760
2761         return RX_QUEUED;
2762 }
2763
2764 /* TODO: use IEEE80211_RX_FRAGMENTED */
2765 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2766                                         struct ieee80211_rate *rate)
2767 {
2768         struct ieee80211_sub_if_data *sdata;
2769         struct ieee80211_local *local = rx->local;
2770         struct sk_buff *skb = rx->skb, *skb2;
2771         struct net_device *prev_dev = NULL;
2772         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2773         int needed_headroom;
2774
2775         /*
2776          * If cooked monitor has been processed already, then
2777          * don't do it again. If not, set the flag.
2778          */
2779         if (rx->flags & IEEE80211_RX_CMNTR)
2780                 goto out_free_skb;
2781         rx->flags |= IEEE80211_RX_CMNTR;
2782
2783         /* If there are no cooked monitor interfaces, just free the SKB */
2784         if (!local->cooked_mntrs)
2785                 goto out_free_skb;
2786
2787         /* room for the radiotap header based on driver features */
2788         needed_headroom = ieee80211_rx_radiotap_space(local, status);
2789
2790         if (skb_headroom(skb) < needed_headroom &&
2791             pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC))
2792                 goto out_free_skb;
2793
2794         /* prepend radiotap information */
2795         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
2796                                          false);
2797
2798         skb_set_mac_header(skb, 0);
2799         skb->ip_summed = CHECKSUM_UNNECESSARY;
2800         skb->pkt_type = PACKET_OTHERHOST;
2801         skb->protocol = htons(ETH_P_802_2);
2802
2803         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2804                 if (!ieee80211_sdata_running(sdata))
2805                         continue;
2806
2807                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2808                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2809                         continue;
2810
2811                 if (prev_dev) {
2812                         skb2 = skb_clone(skb, GFP_ATOMIC);
2813                         if (skb2) {
2814                                 skb2->dev = prev_dev;
2815                                 netif_receive_skb(skb2);
2816                         }
2817                 }
2818
2819                 prev_dev = sdata->dev;
2820                 sdata->dev->stats.rx_packets++;
2821                 sdata->dev->stats.rx_bytes += skb->len;
2822         }
2823
2824         if (prev_dev) {
2825                 skb->dev = prev_dev;
2826                 netif_receive_skb(skb);
2827                 return;
2828         }
2829
2830  out_free_skb:
2831         dev_kfree_skb(skb);
2832 }
2833
2834 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
2835                                          ieee80211_rx_result res)
2836 {
2837         switch (res) {
2838         case RX_DROP_MONITOR:
2839                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2840                 if (rx->sta)
2841                         rx->sta->rx_dropped++;
2842                 /* fall through */
2843         case RX_CONTINUE: {
2844                 struct ieee80211_rate *rate = NULL;
2845                 struct ieee80211_supported_band *sband;
2846                 struct ieee80211_rx_status *status;
2847
2848                 status = IEEE80211_SKB_RXCB((rx->skb));
2849
2850                 sband = rx->local->hw.wiphy->bands[status->band];
2851                 if (!(status->flag & RX_FLAG_HT) &&
2852                     !(status->flag & RX_FLAG_VHT))
2853                         rate = &sband->bitrates[status->rate_idx];
2854
2855                 ieee80211_rx_cooked_monitor(rx, rate);
2856                 break;
2857                 }
2858         case RX_DROP_UNUSABLE:
2859                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2860                 if (rx->sta)
2861                         rx->sta->rx_dropped++;
2862                 dev_kfree_skb(rx->skb);
2863                 break;
2864         case RX_QUEUED:
2865                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
2866                 break;
2867         }
2868 }
2869
2870 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
2871                                   struct sk_buff_head *frames)
2872 {
2873         ieee80211_rx_result res = RX_DROP_MONITOR;
2874         struct sk_buff *skb;
2875
2876 #define CALL_RXH(rxh)                   \
2877         do {                            \
2878                 res = rxh(rx);          \
2879                 if (res != RX_CONTINUE) \
2880                         goto rxh_next;  \
2881         } while (0);
2882
2883         spin_lock_bh(&rx->local->rx_path_lock);
2884
2885         while ((skb = __skb_dequeue(frames))) {
2886                 /*
2887                  * all the other fields are valid across frames
2888                  * that belong to an aMPDU since they are on the
2889                  * same TID from the same station
2890                  */
2891                 rx->skb = skb;
2892
2893                 CALL_RXH(ieee80211_rx_h_decrypt)
2894                 CALL_RXH(ieee80211_rx_h_check_more_data)
2895                 CALL_RXH(ieee80211_rx_h_uapsd_and_pspoll)
2896                 CALL_RXH(ieee80211_rx_h_sta_process)
2897                 CALL_RXH(ieee80211_rx_h_defragment)
2898                 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2899                 /* must be after MMIC verify so header is counted in MPDU mic */
2900 #ifdef CONFIG_MAC80211_MESH
2901                 if (ieee80211_vif_is_mesh(&rx->sdata->vif))
2902                         CALL_RXH(ieee80211_rx_h_mesh_fwding);
2903 #endif
2904                 CALL_RXH(ieee80211_rx_h_amsdu)
2905                 CALL_RXH(ieee80211_rx_h_data)
2906
2907                 /* special treatment -- needs the queue */
2908                 res = ieee80211_rx_h_ctrl(rx, frames);
2909                 if (res != RX_CONTINUE)
2910                         goto rxh_next;
2911
2912                 CALL_RXH(ieee80211_rx_h_mgmt_check)
2913                 CALL_RXH(ieee80211_rx_h_action)
2914                 CALL_RXH(ieee80211_rx_h_userspace_mgmt)
2915                 CALL_RXH(ieee80211_rx_h_action_return)
2916                 CALL_RXH(ieee80211_rx_h_mgmt)
2917
2918  rxh_next:
2919                 ieee80211_rx_handlers_result(rx, res);
2920
2921 #undef CALL_RXH
2922         }
2923
2924         spin_unlock_bh(&rx->local->rx_path_lock);
2925 }
2926
2927 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
2928 {
2929         struct sk_buff_head reorder_release;
2930         ieee80211_rx_result res = RX_DROP_MONITOR;
2931
2932         __skb_queue_head_init(&reorder_release);
2933
2934 #define CALL_RXH(rxh)                   \
2935         do {                            \
2936                 res = rxh(rx);          \
2937                 if (res != RX_CONTINUE) \
2938                         goto rxh_next;  \
2939         } while (0);
2940
2941         CALL_RXH(ieee80211_rx_h_check)
2942
2943         ieee80211_rx_reorder_ampdu(rx, &reorder_release);
2944
2945         ieee80211_rx_handlers(rx, &reorder_release);
2946         return;
2947
2948  rxh_next:
2949         ieee80211_rx_handlers_result(rx, res);
2950
2951 #undef CALL_RXH
2952 }
2953
2954 /*
2955  * This function makes calls into the RX path, therefore
2956  * it has to be invoked under RCU read lock.
2957  */
2958 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
2959 {
2960         struct sk_buff_head frames;
2961         struct ieee80211_rx_data rx = {
2962                 .sta = sta,
2963                 .sdata = sta->sdata,
2964                 .local = sta->local,
2965                 /* This is OK -- must be QoS data frame */
2966                 .security_idx = tid,
2967                 .seqno_idx = tid,
2968                 .flags = 0,
2969         };
2970         struct tid_ampdu_rx *tid_agg_rx;
2971
2972         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
2973         if (!tid_agg_rx)
2974                 return;
2975
2976         __skb_queue_head_init(&frames);
2977
2978         spin_lock(&tid_agg_rx->reorder_lock);
2979         ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx, &frames);
2980         spin_unlock(&tid_agg_rx->reorder_lock);
2981
2982         ieee80211_rx_handlers(&rx, &frames);
2983 }
2984
2985 /* main receive path */
2986
2987 static int prepare_for_handlers(struct ieee80211_rx_data *rx,
2988                                 struct ieee80211_hdr *hdr)
2989 {
2990         struct ieee80211_sub_if_data *sdata = rx->sdata;
2991         struct sk_buff *skb = rx->skb;
2992         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2993         u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2994         int multicast = is_multicast_ether_addr(hdr->addr1);
2995
2996         switch (sdata->vif.type) {
2997         case NL80211_IFTYPE_STATION:
2998                 if (!bssid && !sdata->u.mgd.use_4addr)
2999                         return 0;
3000                 if (!multicast &&
3001                     !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
3002                         if (!(sdata->dev->flags & IFF_PROMISC) ||
3003                             sdata->u.mgd.use_4addr)
3004                                 return 0;
3005                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3006                 }
3007                 break;
3008         case NL80211_IFTYPE_ADHOC:
3009                 if (!bssid)
3010                         return 0;
3011                 if (ieee80211_is_beacon(hdr->frame_control)) {
3012                         return 1;
3013                 } else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
3014                         return 0;
3015                 } else if (!multicast &&
3016                            !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
3017                         if (!(sdata->dev->flags & IFF_PROMISC))
3018                                 return 0;
3019                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3020                 } else if (!rx->sta) {
3021                         int rate_idx;
3022                         if (status->flag & (RX_FLAG_HT | RX_FLAG_VHT))
3023                                 rate_idx = 0; /* TODO: HT/VHT rates */
3024                         else
3025                                 rate_idx = status->rate_idx;
3026                         ieee80211_ibss_rx_no_sta(sdata, bssid, hdr->addr2,
3027                                                  BIT(rate_idx));
3028                 }
3029                 break;
3030         case NL80211_IFTYPE_MESH_POINT:
3031                 if (!multicast &&
3032                     !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
3033                         if (!(sdata->dev->flags & IFF_PROMISC))
3034                                 return 0;
3035
3036                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3037                 }
3038                 break;
3039         case NL80211_IFTYPE_AP_VLAN:
3040         case NL80211_IFTYPE_AP:
3041                 if (!bssid) {
3042                         if (!ether_addr_equal(sdata->vif.addr, hdr->addr1))
3043                                 return 0;
3044                 } else if (!ieee80211_bssid_match(bssid, sdata->vif.addr)) {
3045                         /*
3046                          * Accept public action frames even when the
3047                          * BSSID doesn't match, this is used for P2P
3048                          * and location updates. Note that mac80211
3049                          * itself never looks at these frames.
3050                          */
3051                         if (!multicast &&
3052                             !ether_addr_equal(sdata->vif.addr, hdr->addr1))
3053                                 return 0;
3054                         if (ieee80211_is_public_action(hdr, skb->len))
3055                                 return 1;
3056                         if (!ieee80211_is_beacon(hdr->frame_control))
3057                                 return 0;
3058                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3059                 }
3060                 break;
3061         case NL80211_IFTYPE_WDS:
3062                 if (bssid || !ieee80211_is_data(hdr->frame_control))
3063                         return 0;
3064                 if (!ether_addr_equal(sdata->u.wds.remote_addr, hdr->addr2))
3065                         return 0;
3066                 break;
3067         case NL80211_IFTYPE_P2P_DEVICE:
3068                 if (!ieee80211_is_public_action(hdr, skb->len) &&
3069                     !ieee80211_is_probe_req(hdr->frame_control) &&
3070                     !ieee80211_is_probe_resp(hdr->frame_control) &&
3071                     !ieee80211_is_beacon(hdr->frame_control))
3072                         return 0;
3073                 if (!ether_addr_equal(sdata->vif.addr, hdr->addr1) &&
3074                     !multicast)
3075                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3076                 break;
3077         default:
3078                 /* should never get here */
3079                 WARN_ON_ONCE(1);
3080                 break;
3081         }
3082
3083         return 1;
3084 }
3085
3086 /*
3087  * This function returns whether or not the SKB
3088  * was destined for RX processing or not, which,
3089  * if consume is true, is equivalent to whether
3090  * or not the skb was consumed.
3091  */
3092 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
3093                                             struct sk_buff *skb, bool consume)
3094 {
3095         struct ieee80211_local *local = rx->local;
3096         struct ieee80211_sub_if_data *sdata = rx->sdata;
3097         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3098         struct ieee80211_hdr *hdr = (void *)skb->data;
3099         int prepares;
3100
3101         rx->skb = skb;
3102         status->rx_flags |= IEEE80211_RX_RA_MATCH;
3103         prepares = prepare_for_handlers(rx, hdr);
3104
3105         if (!prepares)
3106                 return false;
3107
3108         if (!consume) {
3109                 skb = skb_copy(skb, GFP_ATOMIC);
3110                 if (!skb) {
3111                         if (net_ratelimit())
3112                                 wiphy_debug(local->hw.wiphy,
3113                                         "failed to copy skb for %s\n",
3114                                         sdata->name);
3115                         return true;
3116                 }
3117
3118                 rx->skb = skb;
3119         }
3120
3121         ieee80211_invoke_rx_handlers(rx);
3122         return true;
3123 }
3124
3125 /*
3126  * This is the actual Rx frames handler. as it blongs to Rx path it must
3127  * be called with rcu_read_lock protection.
3128  */
3129 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
3130                                          struct sk_buff *skb)
3131 {
3132         struct ieee80211_local *local = hw_to_local(hw);
3133         struct ieee80211_sub_if_data *sdata;
3134         struct ieee80211_hdr *hdr;
3135         __le16 fc;
3136         struct ieee80211_rx_data rx;
3137         struct ieee80211_sub_if_data *prev;
3138         struct sta_info *sta, *tmp, *prev_sta;
3139         int err = 0;
3140
3141         fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
3142         memset(&rx, 0, sizeof(rx));
3143         rx.skb = skb;
3144         rx.local = local;
3145
3146         if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
3147                 local->dot11ReceivedFragmentCount++;
3148
3149         if (ieee80211_is_mgmt(fc)) {
3150                 /* drop frame if too short for header */
3151                 if (skb->len < ieee80211_hdrlen(fc))
3152                         err = -ENOBUFS;
3153                 else
3154                         err = skb_linearize(skb);
3155         } else {
3156                 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
3157         }
3158
3159         if (err) {
3160                 dev_kfree_skb(skb);
3161                 return;
3162         }
3163
3164         hdr = (struct ieee80211_hdr *)skb->data;
3165         ieee80211_parse_qos(&rx);
3166         ieee80211_verify_alignment(&rx);
3167
3168         if (unlikely(ieee80211_is_probe_resp(hdr->frame_control) ||
3169                      ieee80211_is_beacon(hdr->frame_control)))
3170                 ieee80211_scan_rx(local, skb);
3171
3172         if (ieee80211_is_data(fc)) {
3173                 prev_sta = NULL;
3174
3175                 for_each_sta_info(local, hdr->addr2, sta, tmp) {
3176                         if (!prev_sta) {
3177                                 prev_sta = sta;
3178                                 continue;
3179                         }
3180
3181                         rx.sta = prev_sta;
3182                         rx.sdata = prev_sta->sdata;
3183                         ieee80211_prepare_and_rx_handle(&rx, skb, false);
3184
3185                         prev_sta = sta;
3186                 }
3187
3188                 if (prev_sta) {
3189                         rx.sta = prev_sta;
3190                         rx.sdata = prev_sta->sdata;
3191
3192                         if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
3193                                 return;
3194                         goto out;
3195                 }
3196         }
3197
3198         prev = NULL;
3199
3200         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
3201                 if (!ieee80211_sdata_running(sdata))
3202                         continue;
3203
3204                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
3205                     sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
3206                         continue;
3207
3208                 /*
3209                  * frame is destined for this interface, but if it's
3210                  * not also for the previous one we handle that after
3211                  * the loop to avoid copying the SKB once too much
3212                  */
3213
3214                 if (!prev) {
3215                         prev = sdata;
3216                         continue;
3217                 }
3218
3219                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
3220                 rx.sdata = prev;
3221                 ieee80211_prepare_and_rx_handle(&rx, skb, false);
3222
3223                 prev = sdata;
3224         }
3225
3226         if (prev) {
3227                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
3228                 rx.sdata = prev;
3229
3230                 if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
3231                         return;
3232         }
3233
3234  out:
3235         dev_kfree_skb(skb);
3236 }
3237
3238 /*
3239  * This is the receive path handler. It is called by a low level driver when an
3240  * 802.11 MPDU is received from the hardware.
3241  */
3242 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
3243 {
3244         struct ieee80211_local *local = hw_to_local(hw);
3245         struct ieee80211_rate *rate = NULL;
3246         struct ieee80211_supported_band *sband;
3247         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3248
3249         WARN_ON_ONCE(softirq_count() == 0);
3250
3251         if (WARN_ON(status->band >= IEEE80211_NUM_BANDS))
3252                 goto drop;
3253
3254         sband = local->hw.wiphy->bands[status->band];
3255         if (WARN_ON(!sband))
3256                 goto drop;
3257
3258         /*
3259          * If we're suspending, it is possible although not too likely
3260          * that we'd be receiving frames after having already partially
3261          * quiesced the stack. We can't process such frames then since
3262          * that might, for example, cause stations to be added or other
3263          * driver callbacks be invoked.
3264          */
3265         if (unlikely(local->quiescing || local->suspended))
3266                 goto drop;
3267
3268         /* We might be during a HW reconfig, prevent Rx for the same reason */
3269         if (unlikely(local->in_reconfig))
3270                 goto drop;
3271
3272         /*
3273          * The same happens when we're not even started,
3274          * but that's worth a warning.
3275          */
3276         if (WARN_ON(!local->started))
3277                 goto drop;
3278
3279         if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
3280                 /*
3281                  * Validate the rate, unless a PLCP error means that
3282                  * we probably can't have a valid rate here anyway.
3283                  */
3284
3285                 if (status->flag & RX_FLAG_HT) {
3286                         /*
3287                          * rate_idx is MCS index, which can be [0-76]
3288                          * as documented on:
3289                          *
3290                          * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
3291                          *
3292                          * Anything else would be some sort of driver or
3293                          * hardware error. The driver should catch hardware
3294                          * errors.
3295                          */
3296                         if (WARN(status->rate_idx > 76,
3297                                  "Rate marked as an HT rate but passed "
3298                                  "status->rate_idx is not "
3299                                  "an MCS index [0-76]: %d (0x%02x)\n",
3300                                  status->rate_idx,
3301                                  status->rate_idx))
3302                                 goto drop;
3303                 } else if (status->flag & RX_FLAG_VHT) {
3304                         if (WARN_ONCE(status->rate_idx > 9 ||
3305                                       !status->vht_nss ||
3306                                       status->vht_nss > 8,
3307                                       "Rate marked as a VHT rate but data is invalid: MCS: %d, NSS: %d\n",
3308                                       status->rate_idx, status->vht_nss))
3309                                 goto drop;
3310                 } else {
3311                         if (WARN_ON(status->rate_idx >= sband->n_bitrates))
3312                                 goto drop;
3313                         rate = &sband->bitrates[status->rate_idx];
3314                 }
3315         }
3316
3317         status->rx_flags = 0;
3318
3319         /*
3320          * key references and virtual interfaces are protected using RCU
3321          * and this requires that we are in a read-side RCU section during
3322          * receive processing
3323          */
3324         rcu_read_lock();
3325
3326         /*
3327          * Frames with failed FCS/PLCP checksum are not returned,
3328          * all other frames are returned without radiotap header
3329          * if it was previously present.
3330          * Also, frames with less than 16 bytes are dropped.
3331          */
3332         skb = ieee80211_rx_monitor(local, skb, rate);
3333         if (!skb) {
3334                 rcu_read_unlock();
3335                 return;
3336         }
3337
3338         ieee80211_tpt_led_trig_rx(local,
3339                         ((struct ieee80211_hdr *)skb->data)->frame_control,
3340                         skb->len);
3341         __ieee80211_rx_handle_packet(hw, skb);
3342
3343         rcu_read_unlock();
3344
3345         return;
3346  drop:
3347         kfree_skb(skb);
3348 }
3349 EXPORT_SYMBOL(ieee80211_rx);
3350
3351 /* This is a version of the rx handler that can be called from hard irq
3352  * context. Post the skb on the queue and schedule the tasklet */
3353 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
3354 {
3355         struct ieee80211_local *local = hw_to_local(hw);
3356
3357         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
3358
3359         skb->pkt_type = IEEE80211_RX_MSG;
3360         skb_queue_tail(&local->skb_queue, skb);
3361         tasklet_schedule(&local->tasklet);
3362 }
3363 EXPORT_SYMBOL(ieee80211_rx_irqsafe);