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  * Copyright 2013-2014  Intel Mobile Communications GmbH
   7  * Copyright(c) 2015 - 2017 Intel Deutschland GmbH
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  */
  13
  14 #include <linux/jiffies.h>
  15 #include <linux/slab.h>
  16 #include <linux/kernel.h>
  17 #include <linux/skbuff.h>
  18 #include <linux/netdevice.h>
  19 #include <linux/etherdevice.h>
  20 #include <linux/rcupdate.h>
  21 #include <linux/export.h>
  22 #include <linux/bitops.h>
  23 #include <net/mac80211.h>
  24 #include <net/ieee80211_radiotap.h>
  25 #include <asm/unaligned.h>
  26
  27 #include "ieee80211_i.h"
  28 #include "driver-ops.h"
  29 #include "led.h"
  30 #include "mesh.h"
  31 #include "wep.h"
  32 #include "wpa.h"
  33 #include "tkip.h"
  34 #include "wme.h"
  35 #include "rate.h"
  36
  37 static inline void ieee80211_rx_stats(struct net_device *dev, u32 len)
  38 {
  39         struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats);
  40
  41         u64_stats_update_begin(&tstats->syncp);
  42         tstats->rx_packets++;
  43         tstats->rx_bytes += len;
  44         u64_stats_update_end(&tstats->syncp);
  45 }
  46
  47 static u8 *ieee80211_get_bssid(struct ieee80211_hdr *hdr, size_t len,
  48                                enum nl80211_iftype type)
  49 {
  50         __le16 fc = hdr->frame_control;
  51
  52         if (ieee80211_is_data(fc)) {
  53                 if (len < 24) /* drop incorrect hdr len (data) */
  54                         return NULL;
  55
  56                 if (ieee80211_has_a4(fc))
  57                         return NULL;
  58                 if (ieee80211_has_tods(fc))
  59                         return hdr->addr1;
  60                 if (ieee80211_has_fromds(fc))
  61                         return hdr->addr2;
  62
  63                 return hdr->addr3;
  64         }
  65
  66         if (ieee80211_is_mgmt(fc)) {
  67                 if (len < 24) /* drop incorrect hdr len (mgmt) */
  68                         return NULL;
  69                 return hdr->addr3;
  70         }
  71
  72         if (ieee80211_is_ctl(fc)) {
  73                 if (ieee80211_is_pspoll(fc))
  74                         return hdr->addr1;
  75
  76                 if (ieee80211_is_back_req(fc)) {
  77                         switch (type) {
  78                         case NL80211_IFTYPE_STATION:
  79                                 return hdr->addr2;
  80                         case NL80211_IFTYPE_AP:
  81                         case NL80211_IFTYPE_AP_VLAN:
  82                                 return hdr->addr1;
  83                         default:
  84                                 break; /* fall through to the return */
  85                         }
  86                 }
  87         }
  88
  89         return NULL;
  90 }
  91
  92 /*
  93  * monitor mode reception
  94  *
  95  * This function cleans up the SKB, i.e. it removes all the stuff
  96  * only useful for monitoring.
  97  */
  98 static void remove_monitor_info(struct sk_buff *skb,
  99                                 unsigned int present_fcs_len,
 100                                 unsigned int rtap_vendor_space)
 101 {
 102         if (present_fcs_len)
 103                 __pskb_trim(skb, skb->len - present_fcs_len);
 104         __pskb_pull(skb, rtap_vendor_space);
 105 }
 106
 107 static inline bool should_drop_frame(struct sk_buff *skb, int present_fcs_len,
 108                                      unsigned int rtap_vendor_space)
 109 {
 110         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 111         struct ieee80211_hdr *hdr;
 112
 113         hdr = (void *)(skb->data + rtap_vendor_space);
 114
 115         if (status->flag & (RX_FLAG_FAILED_FCS_CRC |
 116                             RX_FLAG_FAILED_PLCP_CRC |
 117                             RX_FLAG_ONLY_MONITOR))
 118                 return true;
 119
 120         if (unlikely(skb->len < 16 + present_fcs_len + rtap_vendor_space))
 121                 return true;
 122
 123         if (ieee80211_is_ctl(hdr->frame_control) &&
 124             !ieee80211_is_pspoll(hdr->frame_control) &&
 125             !ieee80211_is_back_req(hdr->frame_control))
 126                 return true;
 127
 128         return false;
 129 }
 130
 131 static int
 132 ieee80211_rx_radiotap_hdrlen(struct ieee80211_local *local,
 133                              struct ieee80211_rx_status *status,
 134                              struct sk_buff *skb)
 135 {
 136         int len;
 137
 138         /* always present fields */
 139         len = sizeof(struct ieee80211_radiotap_header) + 8;
 140
 141         /* allocate extra bitmaps */
 142         if (status->chains)
 143                 len += 4 * hweight8(status->chains);
 144
 145         if (ieee80211_have_rx_timestamp(status)) {
 146                 len = ALIGN(len, 8);
 147                 len += 8;
 148         }
 149         if (ieee80211_hw_check(&local->hw, SIGNAL_DBM))
 150                 len += 1;
 151
 152         /* antenna field, if we don't have per-chain info */
 153         if (!status->chains)
 154                 len += 1;
 155
 156         /* padding for RX_FLAGS if necessary */
 157         len = ALIGN(len, 2);
 158
 159         if (status->encoding == RX_ENC_HT) /* HT info */
 160                 len += 3;
 161
 162         if (status->flag & RX_FLAG_AMPDU_DETAILS) {
 163                 len = ALIGN(len, 4);
 164                 len += 8;
 165         }
 166
 167         if (status->encoding == RX_ENC_VHT) {
 168                 len = ALIGN(len, 2);
 169                 len += 12;
 170         }
 171
 172         if (local->hw.radiotap_timestamp.units_pos >= 0) {
 173                 len = ALIGN(len, 8);
 174                 len += 12;
 175         }
 176
 177         if (status->chains) {
 178                 /* antenna and antenna signal fields */
 179                 len += 2 * hweight8(status->chains);
 180         }
 181
 182         if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) {
 183                 struct ieee80211_vendor_radiotap *rtap = (void *)skb->data;
 184
 185                 /* vendor presence bitmap */
 186                 len += 4;
 187                 /* alignment for fixed 6-byte vendor data header */
 188                 len = ALIGN(len, 2);
 189                 /* vendor data header */
 190                 len += 6;
 191                 if (WARN_ON(rtap->align == 0))
 192                         rtap->align = 1;
 193                 len = ALIGN(len, rtap->align);
 194                 len += rtap->len + rtap->pad;
 195         }
 196
 197         return len;
 198 }
 199
 200 static void ieee80211_handle_mu_mimo_mon(struct ieee80211_sub_if_data *sdata,
 201                                          struct sk_buff *skb,
 202                                          int rtap_vendor_space)
 203 {
 204         struct {
 205                 struct ieee80211_hdr_3addr hdr;
 206                 u8 category;
 207                 u8 action_code;
 208         } __packed action;
 209
 210         if (!sdata)
 211                 return;
 212
 213         BUILD_BUG_ON(sizeof(action) != IEEE80211_MIN_ACTION_SIZE + 1);
 214
 215         if (skb->len < rtap_vendor_space + sizeof(action) +
 216                        VHT_MUMIMO_GROUPS_DATA_LEN)
 217                 return;
 218
 219         if (!is_valid_ether_addr(sdata->u.mntr.mu_follow_addr))
 220                 return;
 221
 222         skb_copy_bits(skb, rtap_vendor_space, &action, sizeof(action));
 223
 224         if (!ieee80211_is_action(action.hdr.frame_control))
 225                 return;
 226
 227         if (action.category != WLAN_CATEGORY_VHT)
 228                 return;
 229
 230         if (action.action_code != WLAN_VHT_ACTION_GROUPID_MGMT)
 231                 return;
 232
 233         if (!ether_addr_equal(action.hdr.addr1, sdata->u.mntr.mu_follow_addr))
 234                 return;
 235
 236         skb = skb_copy(skb, GFP_ATOMIC);
 237         if (!skb)
 238                 return;
 239
 240         skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
 241         skb_queue_tail(&sdata->skb_queue, skb);
 242         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 243 }
 244
 245 /*
 246  * ieee80211_add_rx_radiotap_header - add radiotap header
 247  *
 248  * add a radiotap header containing all the fields which the hardware provided.
 249  */
 250 static void
 251 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
 252                                  struct sk_buff *skb,
 253                                  struct ieee80211_rate *rate,
 254                                  int rtap_len, bool has_fcs)
 255 {
 256         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 257         struct ieee80211_radiotap_header *rthdr;
 258         unsigned char *pos;
 259         __le32 *it_present;
 260         u32 it_present_val;
 261         u16 rx_flags = 0;
 262         u16 channel_flags = 0;
 263         int mpdulen, chain;
 264         unsigned long chains = status->chains;
 265         struct ieee80211_vendor_radiotap rtap = {};
 266
 267         if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) {
 268                 rtap = *(struct ieee80211_vendor_radiotap *)skb->data;
 269                 /* rtap.len and rtap.pad are undone immediately */
 270                 skb_pull(skb, sizeof(rtap) + rtap.len + rtap.pad);
 271         }
 272
 273         mpdulen = skb->len;
 274         if (!(has_fcs && ieee80211_hw_check(&local->hw, RX_INCLUDES_FCS)))
 275                 mpdulen += FCS_LEN;
 276
 277         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
 278         memset(rthdr, 0, rtap_len - rtap.len - rtap.pad);
 279         it_present = &rthdr->it_present;
 280
 281         /* radiotap header, set always present flags */
 282         rthdr->it_len = cpu_to_le16(rtap_len);
 283         it_present_val = BIT(IEEE80211_RADIOTAP_FLAGS) |
 284                          BIT(IEEE80211_RADIOTAP_CHANNEL) |
 285                          BIT(IEEE80211_RADIOTAP_RX_FLAGS);
 286
 287         if (!status->chains)
 288                 it_present_val |= BIT(IEEE80211_RADIOTAP_ANTENNA);
 289
 290         for_each_set_bit(chain, &chains, IEEE80211_MAX_CHAINS) {
 291                 it_present_val |=
 292                         BIT(IEEE80211_RADIOTAP_EXT) |
 293                         BIT(IEEE80211_RADIOTAP_RADIOTAP_NAMESPACE);
 294                 put_unaligned_le32(it_present_val, it_present);
 295                 it_present++;
 296                 it_present_val = BIT(IEEE80211_RADIOTAP_ANTENNA) |
 297                                  BIT(IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
 298         }
 299
 300         if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) {
 301                 it_present_val |= BIT(IEEE80211_RADIOTAP_VENDOR_NAMESPACE) |
 302                                   BIT(IEEE80211_RADIOTAP_EXT);
 303                 put_unaligned_le32(it_present_val, it_present);
 304                 it_present++;
 305                 it_present_val = rtap.present;
 306         }
 307
 308         put_unaligned_le32(it_present_val, it_present);
 309
 310         pos = (void *)(it_present + 1);
 311
 312         /* the order of the following fields is important */
 313
 314         /* IEEE80211_RADIOTAP_TSFT */
 315         if (ieee80211_have_rx_timestamp(status)) {
 316                 /* padding */
 317                 while ((pos - (u8 *)rthdr) & 7)
 318                         *pos++ = 0;
 319                 put_unaligned_le64(
 320                         ieee80211_calculate_rx_timestamp(local, status,
 321                                                          mpdulen, 0),
 322                         pos);
 323                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
 324                 pos += 8;
 325         }
 326
 327         /* IEEE80211_RADIOTAP_FLAGS */
 328         if (has_fcs && ieee80211_hw_check(&local->hw, RX_INCLUDES_FCS))
 329                 *pos |= IEEE80211_RADIOTAP_F_FCS;
 330         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 331                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
 332         if (status->enc_flags & RX_ENC_FLAG_SHORTPRE)
 333                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
 334         pos++;
 335
 336         /* IEEE80211_RADIOTAP_RATE */
 337         if (!rate || status->encoding != RX_ENC_LEGACY) {
 338                 /*
 339                  * Without rate information don't add it. If we have,
 340                  * MCS information is a separate field in radiotap,
 341                  * added below. The byte here is needed as padding
 342                  * for the channel though, so initialise it to 0.
 343                  */
 344                 *pos = 0;
 345         } else {
 346                 int shift = 0;
 347                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
 348                 if (status->bw == RATE_INFO_BW_10)
 349                         shift = 1;
 350                 else if (status->bw == RATE_INFO_BW_5)
 351                         shift = 2;
 352                 *pos = DIV_ROUND_UP(rate->bitrate, 5 * (1 << shift));
 353         }
 354         pos++;
 355
 356         /* IEEE80211_RADIOTAP_CHANNEL */
 357         put_unaligned_le16(status->freq, pos);
 358         pos += 2;
 359         if (status->bw == RATE_INFO_BW_10)
 360                 channel_flags |= IEEE80211_CHAN_HALF;
 361         else if (status->bw == RATE_INFO_BW_5)
 362                 channel_flags |= IEEE80211_CHAN_QUARTER;
 363
 364         if (status->band == NL80211_BAND_5GHZ)
 365                 channel_flags |= IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ;
 366         else if (status->encoding != RX_ENC_LEGACY)
 367                 channel_flags |= IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ;
 368         else if (rate && rate->flags & IEEE80211_RATE_ERP_G)
 369                 channel_flags |= IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ;
 370         else if (rate)
 371                 channel_flags |= IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ;
 372         else
 373                 channel_flags |= IEEE80211_CHAN_2GHZ;
 374         put_unaligned_le16(channel_flags, pos);
 375         pos += 2;
 376
 377         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
 378         if (ieee80211_hw_check(&local->hw, SIGNAL_DBM) &&
 379             !(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
 380                 *pos = status->signal;
 381                 rthdr->it_present |=
 382                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
 383                 pos++;
 384         }
 385
 386         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
 387
 388         if (!status->chains) {
 389                 /* IEEE80211_RADIOTAP_ANTENNA */
 390                 *pos = status->antenna;
 391                 pos++;
 392         }
 393
 394         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
 395
 396         /* IEEE80211_RADIOTAP_RX_FLAGS */
 397         /* ensure 2 byte alignment for the 2 byte field as required */
 398         if ((pos - (u8 *)rthdr) & 1)
 399                 *pos++ = 0;
 400         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
 401                 rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
 402         put_unaligned_le16(rx_flags, pos);
 403         pos += 2;
 404
 405         if (status->encoding == RX_ENC_HT) {
 406                 unsigned int stbc;
 407
 408                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
 409                 *pos++ = local->hw.radiotap_mcs_details;
 410                 *pos = 0;
 411                 if (status->enc_flags & RX_ENC_FLAG_SHORT_GI)
 412                         *pos |= IEEE80211_RADIOTAP_MCS_SGI;
 413                 if (status->bw == RATE_INFO_BW_40)
 414                         *pos |= IEEE80211_RADIOTAP_MCS_BW_40;
 415                 if (status->enc_flags & RX_ENC_FLAG_HT_GF)
 416                         *pos |= IEEE80211_RADIOTAP_MCS_FMT_GF;
 417                 if (status->enc_flags & RX_ENC_FLAG_LDPC)
 418                         *pos |= IEEE80211_RADIOTAP_MCS_FEC_LDPC;
 419                 stbc = (status->enc_flags & RX_ENC_FLAG_STBC_MASK) >> RX_ENC_FLAG_STBC_SHIFT;
 420                 *pos |= stbc << IEEE80211_RADIOTAP_MCS_STBC_SHIFT;
 421                 pos++;
 422                 *pos++ = status->rate_idx;
 423         }
 424
 425         if (status->flag & RX_FLAG_AMPDU_DETAILS) {
 426                 u16 flags = 0;
 427
 428                 /* ensure 4 byte alignment */
 429                 while ((pos - (u8 *)rthdr) & 3)
 430                         pos++;
 431                 rthdr->it_present |=
 432                         cpu_to_le32(1 << IEEE80211_RADIOTAP_AMPDU_STATUS);
 433                 put_unaligned_le32(status->ampdu_reference, pos);
 434                 pos += 4;
 435                 if (status->flag & RX_FLAG_AMPDU_LAST_KNOWN)
 436                         flags |= IEEE80211_RADIOTAP_AMPDU_LAST_KNOWN;
 437                 if (status->flag & RX_FLAG_AMPDU_IS_LAST)
 438                         flags |= IEEE80211_RADIOTAP_AMPDU_IS_LAST;
 439                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_ERROR)
 440                         flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_ERR;
 441                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
 442                         flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_KNOWN;
 443                 put_unaligned_le16(flags, pos);
 444                 pos += 2;
 445                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
 446                         *pos++ = status->ampdu_delimiter_crc;
 447                 else
 448                         *pos++ = 0;
 449                 *pos++ = 0;
 450         }
 451
 452         if (status->encoding == RX_ENC_VHT) {
 453                 u16 known = local->hw.radiotap_vht_details;
 454
 455                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_VHT);
 456                 put_unaligned_le16(known, pos);
 457                 pos += 2;
 458                 /* flags */
 459                 if (status->enc_flags & RX_ENC_FLAG_SHORT_GI)
 460                         *pos |= IEEE80211_RADIOTAP_VHT_FLAG_SGI;
 461                 /* in VHT, STBC is binary */
 462                 if (status->enc_flags & RX_ENC_FLAG_STBC_MASK)
 463                         *pos |= IEEE80211_RADIOTAP_VHT_FLAG_STBC;
 464                 if (status->enc_flags & RX_ENC_FLAG_BF)
 465                         *pos |= IEEE80211_RADIOTAP_VHT_FLAG_BEAMFORMED;
 466                 pos++;
 467                 /* bandwidth */
 468                 switch (status->bw) {
 469                 case RATE_INFO_BW_80:
 470                         *pos++ = 4;
 471                         break;
 472                 case RATE_INFO_BW_160:
 473                         *pos++ = 11;
 474                         break;
 475                 case RATE_INFO_BW_40:
 476                         *pos++ = 1;
 477                         break;
 478                 default:
 479                         *pos++ = 0;
 480                 }
 481                 /* MCS/NSS */
 482                 *pos = (status->rate_idx << 4) | status->nss;
 483                 pos += 4;
 484                 /* coding field */
 485                 if (status->enc_flags & RX_ENC_FLAG_LDPC)
 486                         *pos |= IEEE80211_RADIOTAP_CODING_LDPC_USER0;
 487                 pos++;
 488                 /* group ID */
 489                 pos++;
 490                 /* partial_aid */
 491                 pos += 2;
 492         }
 493
 494         if (local->hw.radiotap_timestamp.units_pos >= 0) {
 495                 u16 accuracy = 0;
 496                 u8 flags = IEEE80211_RADIOTAP_TIMESTAMP_FLAG_32BIT;
 497
 498                 rthdr->it_present |=
 499                         cpu_to_le32(1 << IEEE80211_RADIOTAP_TIMESTAMP);
 500
 501                 /* ensure 8 byte alignment */
 502                 while ((pos - (u8 *)rthdr) & 7)
 503                         pos++;
 504
 505                 put_unaligned_le64(status->device_timestamp, pos);
 506                 pos += sizeof(u64);
 507
 508                 if (local->hw.radiotap_timestamp.accuracy >= 0) {
 509                         accuracy = local->hw.radiotap_timestamp.accuracy;
 510                         flags |= IEEE80211_RADIOTAP_TIMESTAMP_FLAG_ACCURACY;
 511                 }
 512                 put_unaligned_le16(accuracy, pos);
 513                 pos += sizeof(u16);
 514
 515                 *pos++ = local->hw.radiotap_timestamp.units_pos;
 516                 *pos++ = flags;
 517         }
 518
 519         for_each_set_bit(chain, &chains, IEEE80211_MAX_CHAINS) {
 520                 *pos++ = status->chain_signal[chain];
 521                 *pos++ = chain;
 522         }
 523
 524         if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) {
 525                 /* ensure 2 byte alignment for the vendor field as required */
 526                 if ((pos - (u8 *)rthdr) & 1)
 527                         *pos++ = 0;
 528                 *pos++ = rtap.oui[0];
 529                 *pos++ = rtap.oui[1];
 530                 *pos++ = rtap.oui[2];
 531                 *pos++ = rtap.subns;
 532                 put_unaligned_le16(rtap.len, pos);
 533                 pos += 2;
 534                 /* align the actual payload as requested */
 535                 while ((pos - (u8 *)rthdr) & (rtap.align - 1))
 536                         *pos++ = 0;
 537                 /* data (and possible padding) already follows */
 538         }
 539 }
 540
 541 static struct sk_buff *
 542 ieee80211_make_monitor_skb(struct ieee80211_local *local,
 543                            struct sk_buff **origskb,
 544                            struct ieee80211_rate *rate,
 545                            int rtap_vendor_space, bool use_origskb)
 546 {
 547         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(*origskb);
 548         int rt_hdrlen, needed_headroom;
 549         struct sk_buff *skb;
 550
 551         /* room for the radiotap header based on driver features */
 552         rt_hdrlen = ieee80211_rx_radiotap_hdrlen(local, status, *origskb);
 553         needed_headroom = rt_hdrlen - rtap_vendor_space;
 554
 555         if (use_origskb) {
 556                 /* only need to expand headroom if necessary */
 557                 skb = *origskb;
 558                 *origskb = NULL;
 559
 560                 /*
 561                  * This shouldn't trigger often because most devices have an
 562                  * RX header they pull before we get here, and that should
 563                  * be big enough for our radiotap information. We should
 564                  * probably export the length to drivers so that we can have
 565                  * them allocate enough headroom to start with.
 566                  */
 567                 if (skb_headroom(skb) < needed_headroom &&
 568                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
 569                         dev_kfree_skb(skb);
 570                         return NULL;
 571                 }
 572         } else {
 573                 /*
 574                  * Need to make a copy and possibly remove radiotap header
 575                  * and FCS from the original.
 576                  */
 577                 skb = skb_copy_expand(*origskb, needed_headroom, 0, GFP_ATOMIC);
 578
 579                 if (!skb)
 580                         return NULL;
 581         }
 582
 583         /* prepend radiotap information */
 584         ieee80211_add_rx_radiotap_header(local, skb, rate, rt_hdrlen, true);
 585
 586         skb_reset_mac_header(skb);
 587         skb->ip_summed = CHECKSUM_UNNECESSARY;
 588         skb->pkt_type = PACKET_OTHERHOST;
 589         skb->protocol = htons(ETH_P_802_2);
 590
 591         return skb;
 592 }
 593
 594 /*
 595  * This function copies a received frame to all monitor interfaces and
 596  * returns a cleaned-up SKB that no longer includes the FCS nor the
 597  * radiotap header the driver might have added.
 598  */
 599 static struct sk_buff *
 600 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
 601                      struct ieee80211_rate *rate)
 602 {
 603         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
 604         struct ieee80211_sub_if_data *sdata;
 605         struct sk_buff *monskb = NULL;
 606         int present_fcs_len = 0;
 607         unsigned int rtap_vendor_space = 0;
 608         struct ieee80211_sub_if_data *monitor_sdata =
 609                 rcu_dereference(local->monitor_sdata);
 610         bool only_monitor = false;
 611
 612         if (unlikely(status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA)) {
 613                 struct ieee80211_vendor_radiotap *rtap = (void *)origskb->data;
 614
 615                 rtap_vendor_space = sizeof(*rtap) + rtap->len + rtap->pad;
 616         }
 617
 618         /*
 619          * First, we may need to make a copy of the skb because
 620          *  (1) we need to modify it for radiotap (if not present), and
 621          *  (2) the other RX handlers will modify the skb we got.
 622          *
 623          * We don't need to, of course, if we aren't going to return
 624          * the SKB because it has a bad FCS/PLCP checksum.
 625          */
 626
 627         if (ieee80211_hw_check(&local->hw, RX_INCLUDES_FCS)) {
 628                 if (unlikely(origskb->len <= FCS_LEN)) {
 629                         /* driver bug */
 630                         WARN_ON(1);
 631                         dev_kfree_skb(origskb);
 632                         return NULL;
 633                 }
 634                 present_fcs_len = FCS_LEN;
 635         }
 636
 637         /* ensure hdr->frame_control and vendor radiotap data are in skb head */
 638         if (!pskb_may_pull(origskb, 2 + rtap_vendor_space)) {
 639                 dev_kfree_skb(origskb);
 640                 return NULL;
 641         }
 642
 643         only_monitor = should_drop_frame(origskb, present_fcs_len,
 644                                          rtap_vendor_space);
 645
 646         if (!local->monitors || (status->flag & RX_FLAG_SKIP_MONITOR)) {
 647                 if (only_monitor) {
 648                         dev_kfree_skb(origskb);
 649                         return NULL;
 650                 }
 651
 652                 remove_monitor_info(origskb, present_fcs_len,
 653                                     rtap_vendor_space);
 654                 return origskb;
 655         }
 656
 657         ieee80211_handle_mu_mimo_mon(monitor_sdata, origskb, rtap_vendor_space);
 658
 659         list_for_each_entry_rcu(sdata, &local->mon_list, u.mntr.list) {
 660                 bool last_monitor = list_is_last(&sdata->u.mntr.list,
 661                                                  &local->mon_list);
 662
 663                 if (!monskb)
 664                         monskb = ieee80211_make_monitor_skb(local, &origskb,
 665                                                             rate,
 666                                                             rtap_vendor_space,
 667                                                             only_monitor &&
 668                                                             last_monitor);
 669
 670                 if (monskb) {
 671                         struct sk_buff *skb;
 672
 673                         if (last_monitor) {
 674                                 skb = monskb;
 675                                 monskb = NULL;
 676                         } else {
 677                                 skb = skb_clone(monskb, GFP_ATOMIC);
 678                         }
 679
 680                         if (skb) {
 681                                 skb->dev = sdata->dev;
 682                                 ieee80211_rx_stats(skb->dev, skb->len);
 683                                 netif_receive_skb(skb);
 684                         }
 685                 }
 686
 687                 if (last_monitor)
 688                         break;
 689         }
 690
 691         /* this happens if last_monitor was erroneously false */
 692         dev_kfree_skb(monskb);
 693
 694         /* ditto */
 695         if (!origskb)
 696                 return NULL;
 697
 698         remove_monitor_info(origskb, present_fcs_len, rtap_vendor_space);
 699         return origskb;
 700 }
 701
 702 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
 703 {
 704         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 705         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 706         int tid, seqno_idx, security_idx;
 707
 708         /* does the frame have a qos control field? */
 709         if (ieee80211_is_data_qos(hdr->frame_control)) {
 710                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 711                 /* frame has qos control */
 712                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
 713                 if (*qc & IEEE80211_QOS_CTL_A_MSDU_PRESENT)
 714                         status->rx_flags |= IEEE80211_RX_AMSDU;
 715
 716                 seqno_idx = tid;
 717                 security_idx = tid;
 718         } else {
 719                 /*
 720                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
 721                  *
 722                  *      Sequence numbers for management frames, QoS data
 723                  *      frames with a broadcast/multicast address in the
 724                  *      Address 1 field, and all non-QoS data frames sent
 725                  *      by QoS STAs are assigned using an additional single
 726                  *      modulo-4096 counter, [...]
 727                  *
 728                  * We also use that counter for non-QoS STAs.
 729                  */
 730                 seqno_idx = IEEE80211_NUM_TIDS;
 731                 security_idx = 0;
 732                 if (ieee80211_is_mgmt(hdr->frame_control))
 733                         security_idx = IEEE80211_NUM_TIDS;
 734                 tid = 0;
 735         }
 736
 737         rx->seqno_idx = seqno_idx;
 738         rx->security_idx = security_idx;
 739         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 740          * For now, set skb->priority to 0 for other cases. */
 741         rx->skb->priority = (tid > 7) ? 0 : tid;
 742 }
 743
 744 /**
 745  * DOC: Packet alignment
 746  *
 747  * Drivers always need to pass packets that are aligned to two-byte boundaries
 748  * to the stack.
 749  *
 750  * Additionally, should, if possible, align the payload data in a way that
 751  * guarantees that the contained IP header is aligned to a four-byte
 752  * boundary. In the case of regular frames, this simply means aligning the
 753  * payload to a four-byte boundary (because either the IP header is directly
 754  * contained, or IV/RFC1042 headers that have a length divisible by four are
 755  * in front of it).  If the payload data is not properly aligned and the
 756  * architecture doesn't support efficient unaligned operations, mac80211
 757  * will align the data.
 758  *
 759  * With A-MSDU frames, however, the payload data address must yield two modulo
 760  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
 761  * push the IP header further back to a multiple of four again. Thankfully, the
 762  * specs were sane enough this time around to require padding each A-MSDU
 763  * subframe to a length that is a multiple of four.
 764  *
 765  * Padding like Atheros hardware adds which is between the 802.11 header and
 766  * the payload is not supported, the driver is required to move the 802.11
 767  * header to be directly in front of the payload in that case.
 768  */
 769 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
 770 {
 771 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 772         WARN_ON_ONCE((unsigned long)rx->skb->data & 1);
 773 #endif
 774 }
 775
 776
 777 /* rx handlers */
 778
 779 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
 780 {
 781         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 782
 783         if (is_multicast_ether_addr(hdr->addr1))
 784                 return 0;
 785
 786         return ieee80211_is_robust_mgmt_frame(skb);
 787 }
 788
 789
 790 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
 791 {
 792         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 793
 794         if (!is_multicast_ether_addr(hdr->addr1))
 795                 return 0;
 796
 797         return ieee80211_is_robust_mgmt_frame(skb);
 798 }
 799
 800
 801 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
 802 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
 803 {
 804         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
 805         struct ieee80211_mmie *mmie;
 806         struct ieee80211_mmie_16 *mmie16;
 807
 808         if (skb->len < 24 + sizeof(*mmie) || !is_multicast_ether_addr(hdr->da))
 809                 return -1;
 810
 811         if (!ieee80211_is_robust_mgmt_frame(skb))
 812                 return -1; /* not a robust management frame */
 813
 814         mmie = (struct ieee80211_mmie *)
 815                 (skb->data + skb->len - sizeof(*mmie));
 816         if (mmie->element_id == WLAN_EID_MMIE &&
 817             mmie->length == sizeof(*mmie) - 2)
 818                 return le16_to_cpu(mmie->key_id);
 819
 820         mmie16 = (struct ieee80211_mmie_16 *)
 821                 (skb->data + skb->len - sizeof(*mmie16));
 822         if (skb->len >= 24 + sizeof(*mmie16) &&
 823             mmie16->element_id == WLAN_EID_MMIE &&
 824             mmie16->length == sizeof(*mmie16) - 2)
 825                 return le16_to_cpu(mmie16->key_id);
 826
 827         return -1;
 828 }
 829
 830 static int ieee80211_get_cs_keyid(const struct ieee80211_cipher_scheme *cs,
 831                                   struct sk_buff *skb)
 832 {
 833         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 834         __le16 fc;
 835         int hdrlen;
 836         u8 keyid;
 837
 838         fc = hdr->frame_control;
 839         hdrlen = ieee80211_hdrlen(fc);
 840
 841         if (skb->len < hdrlen + cs->hdr_len)
 842                 return -EINVAL;
 843
 844         skb_copy_bits(skb, hdrlen + cs->key_idx_off, &keyid, 1);
 845         keyid &= cs->key_idx_mask;
 846         keyid >>= cs->key_idx_shift;
 847
 848         return keyid;
 849 }
 850
 851 static ieee80211_rx_result ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
 852 {
 853         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 854         char *dev_addr = rx->sdata->vif.addr;
 855
 856         if (ieee80211_is_data(hdr->frame_control)) {
 857                 if (is_multicast_ether_addr(hdr->addr1)) {
 858                         if (ieee80211_has_tods(hdr->frame_control) ||
 859                             !ieee80211_has_fromds(hdr->frame_control))
 860                                 return RX_DROP_MONITOR;
 861                         if (ether_addr_equal(hdr->addr3, dev_addr))
 862                                 return RX_DROP_MONITOR;
 863                 } else {
 864                         if (!ieee80211_has_a4(hdr->frame_control))
 865                                 return RX_DROP_MONITOR;
 866                         if (ether_addr_equal(hdr->addr4, dev_addr))
 867                                 return RX_DROP_MONITOR;
 868                 }
 869         }
 870
 871         /* If there is not an established peer link and this is not a peer link
 872          * establisment frame, beacon or probe, drop the frame.
 873          */
 874
 875         if (!rx->sta || sta_plink_state(rx->sta) != NL80211_PLINK_ESTAB) {
 876                 struct ieee80211_mgmt *mgmt;
 877
 878                 if (!ieee80211_is_mgmt(hdr->frame_control))
 879                         return RX_DROP_MONITOR;
 880
 881                 if (ieee80211_is_action(hdr->frame_control)) {
 882                         u8 category;
 883
 884                         /* make sure category field is present */
 885                         if (rx->skb->len < IEEE80211_MIN_ACTION_SIZE)
 886                                 return RX_DROP_MONITOR;
 887
 888                         mgmt = (struct ieee80211_mgmt *)hdr;
 889                         category = mgmt->u.action.category;
 890                         if (category != WLAN_CATEGORY_MESH_ACTION &&
 891                             category != WLAN_CATEGORY_SELF_PROTECTED)
 892                                 return RX_DROP_MONITOR;
 893                         return RX_CONTINUE;
 894                 }
 895
 896                 if (ieee80211_is_probe_req(hdr->frame_control) ||
 897                     ieee80211_is_probe_resp(hdr->frame_control) ||
 898                     ieee80211_is_beacon(hdr->frame_control) ||
 899                     ieee80211_is_auth(hdr->frame_control))
 900                         return RX_CONTINUE;
 901
 902                 return RX_DROP_MONITOR;
 903         }
 904
 905         return RX_CONTINUE;
 906 }
 907
 908 static inline bool ieee80211_rx_reorder_ready(struct tid_ampdu_rx *tid_agg_rx,
 909                                               int index)
 910 {
 911         struct sk_buff_head *frames = &tid_agg_rx->reorder_buf[index];
 912         struct sk_buff *tail = skb_peek_tail(frames);
 913         struct ieee80211_rx_status *status;
 914
 915         if (tid_agg_rx->reorder_buf_filtered & BIT_ULL(index))
 916                 return true;
 917
 918         if (!tail)
 919                 return false;
 920
 921         status = IEEE80211_SKB_RXCB(tail);
 922         if (status->flag & RX_FLAG_AMSDU_MORE)
 923                 return false;
 924
 925         return true;
 926 }
 927
 928 static void ieee80211_release_reorder_frame(struct ieee80211_sub_if_data *sdata,
 929                                             struct tid_ampdu_rx *tid_agg_rx,
 930                                             int index,
 931                                             struct sk_buff_head *frames)
 932 {
 933         struct sk_buff_head *skb_list = &tid_agg_rx->reorder_buf[index];
 934         struct sk_buff *skb;
 935         struct ieee80211_rx_status *status;
 936
 937         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 938
 939         if (skb_queue_empty(skb_list))
 940                 goto no_frame;
 941
 942         if (!ieee80211_rx_reorder_ready(tid_agg_rx, index)) {
 943                 __skb_queue_purge(skb_list);
 944                 goto no_frame;
 945         }
 946
 947         /* release frames from the reorder ring buffer */
 948         tid_agg_rx->stored_mpdu_num--;
 949         while ((skb = __skb_dequeue(skb_list))) {
 950                 status = IEEE80211_SKB_RXCB(skb);
 951                 status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE;
 952                 __skb_queue_tail(frames, skb);
 953         }
 954
 955 no_frame:
 956         tid_agg_rx->reorder_buf_filtered &= ~BIT_ULL(index);
 957         tid_agg_rx->head_seq_num = ieee80211_sn_inc(tid_agg_rx->head_seq_num);
 958 }
 959
 960 static void ieee80211_release_reorder_frames(struct ieee80211_sub_if_data *sdata,
 961                                              struct tid_ampdu_rx *tid_agg_rx,
 962                                              u16 head_seq_num,
 963                                              struct sk_buff_head *frames)
 964 {
 965         int index;
 966
 967         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 968
 969         while (ieee80211_sn_less(tid_agg_rx->head_seq_num, head_seq_num)) {
 970                 index = tid_agg_rx->head_seq_num % tid_agg_rx->buf_size;
 971                 ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
 972                                                 frames);
 973         }
 974 }
 975
 976 /*
 977  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
 978  * the skb was added to the buffer longer than this time ago, the earlier
 979  * frames that have not yet been received are assumed to be lost and the skb
 980  * can be released for processing. This may also release other skb's from the
 981  * reorder buffer if there are no additional gaps between the frames.
 982  *
 983  * Callers must hold tid_agg_rx->reorder_lock.
 984  */
 985 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
 986
 987 static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata,
 988                                           struct tid_ampdu_rx *tid_agg_rx,
 989                                           struct sk_buff_head *frames)
 990 {
 991         int index, i, j;
 992
 993         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 994
 995         /* release the buffer until next missing frame */
 996         index = tid_agg_rx->head_seq_num % tid_agg_rx->buf_size;
 997         if (!ieee80211_rx_reorder_ready(tid_agg_rx, index) &&
 998             tid_agg_rx->stored_mpdu_num) {
 999                 /*
1000                  * No buffers ready to be released, but check whether any
1001                  * frames in the reorder buffer have timed out.
1002                  */
1003                 int skipped = 1;
1004                 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
1005                      j = (j + 1) % tid_agg_rx->buf_size) {
1006                         if (!ieee80211_rx_reorder_ready(tid_agg_rx, j)) {
1007                                 skipped++;
1008                                 continue;
1009                         }
1010                         if (skipped &&
1011                             !time_after(jiffies, tid_agg_rx->reorder_time[j] +
1012                                         HT_RX_REORDER_BUF_TIMEOUT))
1013                                 goto set_release_timer;
1014
1015                         /* don't leave incomplete A-MSDUs around */
1016                         for (i = (index + 1) % tid_agg_rx->buf_size; i != j;
1017                              i = (i + 1) % tid_agg_rx->buf_size)
1018                                 __skb_queue_purge(&tid_agg_rx->reorder_buf[i]);
1019
1020                         ht_dbg_ratelimited(sdata,
1021                                            "release an RX reorder frame due to timeout on earlier frames\n");
1022                         ieee80211_release_reorder_frame(sdata, tid_agg_rx, j,
1023                                                         frames);
1024
1025                         /*
1026                          * Increment the head seq# also for the skipped slots.
1027                          */
1028                         tid_agg_rx->head_seq_num =
1029                                 (tid_agg_rx->head_seq_num +
1030                                  skipped) & IEEE80211_SN_MASK;
1031                         skipped = 0;
1032                 }
1033         } else while (ieee80211_rx_reorder_ready(tid_agg_rx, index)) {
1034                 ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
1035                                                 frames);
1036                 index = tid_agg_rx->head_seq_num % tid_agg_rx->buf_size;
1037         }
1038
1039         if (tid_agg_rx->stored_mpdu_num) {
1040                 j = index = tid_agg_rx->head_seq_num % tid_agg_rx->buf_size;
1041
1042                 for (; j != (index - 1) % tid_agg_rx->buf_size;
1043                      j = (j + 1) % tid_agg_rx->buf_size) {
1044                         if (ieee80211_rx_reorder_ready(tid_agg_rx, j))
1045                                 break;
1046                 }
1047
1048  set_release_timer:
1049
1050                 if (!tid_agg_rx->removed)
1051                         mod_timer(&tid_agg_rx->reorder_timer,
1052                                   tid_agg_rx->reorder_time[j] + 1 +
1053                                   HT_RX_REORDER_BUF_TIMEOUT);
1054         } else {
1055                 del_timer(&tid_agg_rx->reorder_timer);
1056         }
1057 }
1058
1059 /*
1060  * As this function belongs to the RX path it must be under
1061  * rcu_read_lock protection. It returns false if the frame
1062  * can be processed immediately, true if it was consumed.
1063  */
1064 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_sub_if_data *sdata,
1065                                              struct tid_ampdu_rx *tid_agg_rx,
1066                                              struct sk_buff *skb,
1067                                              struct sk_buff_head *frames)
1068 {
1069         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1070         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1071         u16 sc = le16_to_cpu(hdr->seq_ctrl);
1072         u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
1073         u16 head_seq_num, buf_size;
1074         int index;
1075         bool ret = true;
1076
1077         spin_lock(&tid_agg_rx->reorder_lock);
1078
1079         /*
1080          * Offloaded BA sessions have no known starting sequence number so pick
1081          * one from first Rxed frame for this tid after BA was started.
1082          */
1083         if (unlikely(tid_agg_rx->auto_seq)) {
1084                 tid_agg_rx->auto_seq = false;
1085                 tid_agg_rx->ssn = mpdu_seq_num;
1086                 tid_agg_rx->head_seq_num = mpdu_seq_num;
1087         }
1088
1089         buf_size = tid_agg_rx->buf_size;
1090         head_seq_num = tid_agg_rx->head_seq_num;
1091
1092         /*
1093          * If the current MPDU's SN is smaller than the SSN, it shouldn't
1094          * be reordered.
1095          */
1096         if (unlikely(!tid_agg_rx->started)) {
1097                 if (ieee80211_sn_less(mpdu_seq_num, head_seq_num)) {
1098                         ret = false;
1099                         goto out;
1100                 }
1101                 tid_agg_rx->started = true;
1102         }
1103
1104         /* frame with out of date sequence number */
1105         if (ieee80211_sn_less(mpdu_seq_num, head_seq_num)) {
1106                 dev_kfree_skb(skb);
1107                 goto out;
1108         }
1109
1110         /*
1111          * If frame the sequence number exceeds our buffering window
1112          * size release some previous frames to make room for this one.
1113          */
1114         if (!ieee80211_sn_less(mpdu_seq_num, head_seq_num + buf_size)) {
1115                 head_seq_num = ieee80211_sn_inc(
1116                                 ieee80211_sn_sub(mpdu_seq_num, buf_size));
1117                 /* release stored frames up to new head to stack */
1118                 ieee80211_release_reorder_frames(sdata, tid_agg_rx,
1119                                                  head_seq_num, frames);
1120         }
1121
1122         /* Now the new frame is always in the range of the reordering buffer */
1123
1124         index = mpdu_seq_num % tid_agg_rx->buf_size;
1125
1126         /* check if we already stored this frame */
1127         if (ieee80211_rx_reorder_ready(tid_agg_rx, index)) {
1128                 dev_kfree_skb(skb);
1129                 goto out;
1130         }
1131
1132         /*
1133          * If the current MPDU is in the right order and nothing else
1134          * is stored we can process it directly, no need to buffer it.
1135          * If it is first but there's something stored, we may be able
1136          * to release frames after this one.
1137          */
1138         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
1139             tid_agg_rx->stored_mpdu_num == 0) {
1140                 if (!(status->flag & RX_FLAG_AMSDU_MORE))
1141                         tid_agg_rx->head_seq_num =
1142                                 ieee80211_sn_inc(tid_agg_rx->head_seq_num);
1143                 ret = false;
1144                 goto out;
1145         }
1146
1147         /* put the frame in the reordering buffer */
1148         __skb_queue_tail(&tid_agg_rx->reorder_buf[index], skb);
1149         if (!(status->flag & RX_FLAG_AMSDU_MORE)) {
1150                 tid_agg_rx->reorder_time[index] = jiffies;
1151                 tid_agg_rx->stored_mpdu_num++;
1152                 ieee80211_sta_reorder_release(sdata, tid_agg_rx, frames);
1153         }
1154
1155  out:
1156         spin_unlock(&tid_agg_rx->reorder_lock);
1157         return ret;
1158 }
1159
1160 /*
1161  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
1162  * true if the MPDU was buffered, false if it should be processed.
1163  */
1164 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
1165                                        struct sk_buff_head *frames)
1166 {
1167         struct sk_buff *skb = rx->skb;
1168         struct ieee80211_local *local = rx->local;
1169         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1170         struct sta_info *sta = rx->sta;
1171         struct tid_ampdu_rx *tid_agg_rx;
1172         u16 sc;
1173         u8 tid, ack_policy;
1174
1175         if (!ieee80211_is_data_qos(hdr->frame_control) ||
1176             is_multicast_ether_addr(hdr->addr1))
1177                 goto dont_reorder;
1178
1179         /*
1180          * filter the QoS data rx stream according to
1181          * STA/TID and check if this STA/TID is on aggregation
1182          */
1183
1184         if (!sta)
1185                 goto dont_reorder;
1186
1187         ack_policy = *ieee80211_get_qos_ctl(hdr) &
1188                      IEEE80211_QOS_CTL_ACK_POLICY_MASK;
1189         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
1190
1191         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
1192         if (!tid_agg_rx) {
1193                 if (ack_policy == IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
1194                     !test_bit(tid, rx->sta->ampdu_mlme.agg_session_valid) &&
1195                     !test_and_set_bit(tid, rx->sta->ampdu_mlme.unexpected_agg))
1196                         ieee80211_send_delba(rx->sdata, rx->sta->sta.addr, tid,
1197                                              WLAN_BACK_RECIPIENT,
1198                                              WLAN_REASON_QSTA_REQUIRE_SETUP);
1199                 goto dont_reorder;
1200         }
1201
1202         /* qos null data frames are excluded */
1203         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
1204                 goto dont_reorder;
1205
1206         /* not part of a BA session */
1207         if (ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
1208             ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_NORMAL)
1209                 goto dont_reorder;
1210
1211         /* new, potentially un-ordered, ampdu frame - process it */
1212
1213         /* reset session timer */
1214         if (tid_agg_rx->timeout)
1215                 tid_agg_rx->last_rx = jiffies;
1216
1217         /* if this mpdu is fragmented - terminate rx aggregation session */
1218         sc = le16_to_cpu(hdr->seq_ctrl);
1219         if (sc & IEEE80211_SCTL_FRAG) {
1220                 skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
1221                 skb_queue_tail(&rx->sdata->skb_queue, skb);
1222                 ieee80211_queue_work(&local->hw, &rx->sdata->work);
1223                 return;
1224         }
1225
1226         /*
1227          * No locking needed -- we will only ever process one
1228          * RX packet at a time, and thus own tid_agg_rx. All
1229          * other code manipulating it needs to (and does) make
1230          * sure that we cannot get to it any more before doing
1231          * anything with it.
1232          */
1233         if (ieee80211_sta_manage_reorder_buf(rx->sdata, tid_agg_rx, skb,
1234                                              frames))
1235                 return;
1236
1237  dont_reorder:
1238         __skb_queue_tail(frames, skb);
1239 }
1240
1241 static ieee80211_rx_result debug_noinline
1242 ieee80211_rx_h_check_dup(struct ieee80211_rx_data *rx)
1243 {
1244         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1245         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1246
1247         if (status->flag & RX_FLAG_DUP_VALIDATED)
1248                 return RX_CONTINUE;
1249
1250         /*
1251          * Drop duplicate 802.11 retransmissions
1252          * (IEEE 802.11-2012: 9.3.2.10 "Duplicate detection and recovery")
1253          */
1254
1255         if (rx->skb->len < 24)
1256                 return RX_CONTINUE;
1257
1258         if (ieee80211_is_ctl(hdr->frame_control) ||
1259             ieee80211_is_qos_nullfunc(hdr->frame_control) ||
1260             is_multicast_ether_addr(hdr->addr1))
1261                 return RX_CONTINUE;
1262
1263         if (!rx->sta)
1264                 return RX_CONTINUE;
1265
1266         if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
1267                      rx->sta->last_seq_ctrl[rx->seqno_idx] == hdr->seq_ctrl)) {
1268                 I802_DEBUG_INC(rx->local->dot11FrameDuplicateCount);
1269                 rx->sta->rx_stats.num_duplicates++;
1270                 return RX_DROP_UNUSABLE;
1271         } else if (!(status->flag & RX_FLAG_AMSDU_MORE)) {
1272                 rx->sta->last_seq_ctrl[rx->seqno_idx] = hdr->seq_ctrl;
1273         }
1274
1275         return RX_CONTINUE;
1276 }
1277
1278 static ieee80211_rx_result debug_noinline
1279 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
1280 {
1281         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1282
1283         /* Drop disallowed frame classes based on STA auth/assoc state;
1284          * IEEE 802.11, Chap 5.5.
1285          *
1286          * mac80211 filters only based on association state, i.e. it drops
1287          * Class 3 frames from not associated stations. hostapd sends
1288          * deauth/disassoc frames when needed. In addition, hostapd is
1289          * responsible for filtering on both auth and assoc states.
1290          */
1291
1292         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
1293                 return ieee80211_rx_mesh_check(rx);
1294
1295         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
1296                       ieee80211_is_pspoll(hdr->frame_control)) &&
1297                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
1298                      rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
1299                      rx->sdata->vif.type != NL80211_IFTYPE_OCB &&
1300                      (!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_ASSOC)))) {
1301                 /*
1302                  * accept port control frames from the AP even when it's not
1303                  * yet marked ASSOC to prevent a race where we don't set the
1304                  * assoc bit quickly enough before it sends the first frame
1305                  */
1306                 if (rx->sta && rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1307                     ieee80211_is_data_present(hdr->frame_control)) {
1308                         unsigned int hdrlen;
1309                         __be16 ethertype;
1310
1311                         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1312
1313                         if (rx->skb->len < hdrlen + 8)
1314                                 return RX_DROP_MONITOR;
1315
1316                         skb_copy_bits(rx->skb, hdrlen + 6, &ethertype, 2);
1317                         if (ethertype == rx->sdata->control_port_protocol)
1318                                 return RX_CONTINUE;
1319                 }
1320
1321                 if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
1322                     cfg80211_rx_spurious_frame(rx->sdata->dev,
1323                                                hdr->addr2,
1324                                                GFP_ATOMIC))
1325                         return RX_DROP_UNUSABLE;
1326
1327                 return RX_DROP_MONITOR;
1328         }
1329
1330         return RX_CONTINUE;
1331 }
1332
1333
1334 static ieee80211_rx_result debug_noinline
1335 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1336 {
1337         struct ieee80211_local *local;
1338         struct ieee80211_hdr *hdr;
1339         struct sk_buff *skb;
1340
1341         local = rx->local;
1342         skb = rx->skb;
1343         hdr = (struct ieee80211_hdr *) skb->data;
1344
1345         if (!local->pspolling)
1346                 return RX_CONTINUE;
1347
1348         if (!ieee80211_has_fromds(hdr->frame_control))
1349                 /* this is not from AP */
1350                 return RX_CONTINUE;
1351
1352         if (!ieee80211_is_data(hdr->frame_control))
1353                 return RX_CONTINUE;
1354
1355         if (!ieee80211_has_moredata(hdr->frame_control)) {
1356                 /* AP has no more frames buffered for us */
1357                 local->pspolling = false;
1358                 return RX_CONTINUE;
1359         }
1360
1361         /* more data bit is set, let's request a new frame from the AP */
1362         ieee80211_send_pspoll(local, rx->sdata);
1363
1364         return RX_CONTINUE;
1365 }
1366
1367 static void sta_ps_start(struct sta_info *sta)
1368 {
1369         struct ieee80211_sub_if_data *sdata = sta->sdata;
1370         struct ieee80211_local *local = sdata->local;
1371         struct ps_data *ps;
1372         int tid;
1373
1374         if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
1375             sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1376                 ps = &sdata->bss->ps;
1377         else
1378                 return;
1379
1380         atomic_inc(&ps->num_sta_ps);
1381         set_sta_flag(sta, WLAN_STA_PS_STA);
1382         if (!ieee80211_hw_check(&local->hw, AP_LINK_PS))
1383                 drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1384         ps_dbg(sdata, "STA %pM aid %d enters power save mode\n",
1385                sta->sta.addr, sta->sta.aid);
1386
1387         ieee80211_clear_fast_xmit(sta);
1388
1389         if (!sta->sta.txq[0])
1390                 return;
1391
1392         for (tid = 0; tid < ARRAY_SIZE(sta->sta.txq); tid++) {
1393                 if (txq_has_queue(sta->sta.txq[tid]))
1394                         set_bit(tid, &sta->txq_buffered_tids);
1395                 else
1396                         clear_bit(tid, &sta->txq_buffered_tids);
1397         }
1398 }
1399
1400 static void sta_ps_end(struct sta_info *sta)
1401 {
1402         ps_dbg(sta->sdata, "STA %pM aid %d exits power save mode\n",
1403                sta->sta.addr, sta->sta.aid);
1404
1405         if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) {
1406                 /*
1407                  * Clear the flag only if the other one is still set
1408                  * so that the TX path won't start TX'ing new frames
1409                  * directly ... In the case that the driver flag isn't
1410                  * set ieee80211_sta_ps_deliver_wakeup() will clear it.
1411                  */
1412                 clear_sta_flag(sta, WLAN_STA_PS_STA);
1413                 ps_dbg(sta->sdata, "STA %pM aid %d driver-ps-blocked\n",
1414                        sta->sta.addr, sta->sta.aid);
1415                 return;
1416         }
1417
1418         set_sta_flag(sta, WLAN_STA_PS_DELIVER);
1419         clear_sta_flag(sta, WLAN_STA_PS_STA);
1420         ieee80211_sta_ps_deliver_wakeup(sta);
1421 }
1422
1423 int ieee80211_sta_ps_transition(struct ieee80211_sta *pubsta, bool start)
1424 {
1425         struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
1426         bool in_ps;
1427
1428         WARN_ON(!ieee80211_hw_check(&sta->local->hw, AP_LINK_PS));
1429
1430         /* Don't let the same PS state be set twice */
1431         in_ps = test_sta_flag(sta, WLAN_STA_PS_STA);
1432         if ((start && in_ps) || (!start && !in_ps))
1433                 return -EINVAL;
1434
1435         if (start)
1436                 sta_ps_start(sta);
1437         else
1438                 sta_ps_end(sta);
1439
1440         return 0;
1441 }
1442 EXPORT_SYMBOL(ieee80211_sta_ps_transition);
1443
1444 void ieee80211_sta_pspoll(struct ieee80211_sta *pubsta)
1445 {
1446         struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
1447
1448         if (test_sta_flag(sta, WLAN_STA_SP))
1449                 return;
1450
1451         if (!test_sta_flag(sta, WLAN_STA_PS_DRIVER))
1452                 ieee80211_sta_ps_deliver_poll_response(sta);
1453         else
1454                 set_sta_flag(sta, WLAN_STA_PSPOLL);
1455 }
1456 EXPORT_SYMBOL(ieee80211_sta_pspoll);
1457
1458 void ieee80211_sta_uapsd_trigger(struct ieee80211_sta *pubsta, u8 tid)
1459 {
1460         struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
1461         int ac = ieee80211_ac_from_tid(tid);
1462
1463         /*
1464          * If this AC is not trigger-enabled do nothing unless the
1465          * driver is calling us after it already checked.
1466          *
1467          * NB: This could/should check a separate bitmap of trigger-
1468          * enabled queues, but for now we only implement uAPSD w/o
1469          * TSPEC changes to the ACs, so they're always the same.
1470          */
1471         if (!(sta->sta.uapsd_queues & ieee80211_ac_to_qos_mask[ac]) &&
1472             tid != IEEE80211_NUM_TIDS)
1473                 return;
1474
1475         /* if we are in a service period, do nothing */
1476         if (test_sta_flag(sta, WLAN_STA_SP))
1477                 return;
1478
1479         if (!test_sta_flag(sta, WLAN_STA_PS_DRIVER))
1480                 ieee80211_sta_ps_deliver_uapsd(sta);
1481         else
1482                 set_sta_flag(sta, WLAN_STA_UAPSD);
1483 }
1484 EXPORT_SYMBOL(ieee80211_sta_uapsd_trigger);
1485
1486 static ieee80211_rx_result debug_noinline
1487 ieee80211_rx_h_uapsd_and_pspoll(struct ieee80211_rx_data *rx)
1488 {
1489         struct ieee80211_sub_if_data *sdata = rx->sdata;
1490         struct ieee80211_hdr *hdr = (void *)rx->skb->data;
1491         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1492
1493         if (!rx->sta)
1494                 return RX_CONTINUE;
1495
1496         if (sdata->vif.type != NL80211_IFTYPE_AP &&
1497             sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
1498                 return RX_CONTINUE;
1499
1500         /*
1501          * The device handles station powersave, so don't do anything about
1502          * uAPSD and PS-Poll frames (the latter shouldn't even come up from
1503          * it to mac80211 since they're handled.)
1504          */
1505         if (ieee80211_hw_check(&sdata->local->hw, AP_LINK_PS))
1506                 return RX_CONTINUE;
1507
1508         /*
1509          * Don't do anything if the station isn't already asleep. In
1510          * the uAPSD case, the station will probably be marked asleep,
1511          * in the PS-Poll case the station must be confused ...
1512          */
1513         if (!test_sta_flag(rx->sta, WLAN_STA_PS_STA))
1514                 return RX_CONTINUE;
1515
1516         if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) {
1517                 ieee80211_sta_pspoll(&rx->sta->sta);
1518
1519                 /* Free PS Poll skb here instead of returning RX_DROP that would
1520                  * count as an dropped frame. */
1521                 dev_kfree_skb(rx->skb);
1522
1523                 return RX_QUEUED;
1524         } else if (!ieee80211_has_morefrags(hdr->frame_control) &&
1525                    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1526                    ieee80211_has_pm(hdr->frame_control) &&
1527                    (ieee80211_is_data_qos(hdr->frame_control) ||
1528                     ieee80211_is_qos_nullfunc(hdr->frame_control))) {
1529                 u8 tid;
1530
1531                 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
1532
1533                 ieee80211_sta_uapsd_trigger(&rx->sta->sta, tid);
1534         }
1535
1536         return RX_CONTINUE;
1537 }
1538
1539 static ieee80211_rx_result debug_noinline
1540 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1541 {
1542         struct sta_info *sta = rx->sta;
1543         struct sk_buff *skb = rx->skb;
1544         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1545         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1546         int i;
1547
1548         if (!sta)
1549                 return RX_CONTINUE;
1550
1551         /*
1552          * Update last_rx only for IBSS packets which are for the current
1553          * BSSID and for station already AUTHORIZED to avoid keeping the
1554          * current IBSS network alive in cases where other STAs start
1555          * using different BSSID. This will also give the station another
1556          * chance to restart the authentication/authorization in case
1557          * something went wrong the first time.
1558          */
1559         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1560                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1561                                                 NL80211_IFTYPE_ADHOC);
1562                 if (ether_addr_equal(bssid, rx->sdata->u.ibss.bssid) &&
1563                     test_sta_flag(sta, WLAN_STA_AUTHORIZED)) {
1564                         sta->rx_stats.last_rx = jiffies;
1565                         if (ieee80211_is_data(hdr->frame_control) &&
1566                             !is_multicast_ether_addr(hdr->addr1))
1567                                 sta->rx_stats.last_rate =
1568                                         sta_stats_encode_rate(status);
1569                 }
1570         } else if (rx->sdata->vif.type == NL80211_IFTYPE_OCB) {
1571                 sta->rx_stats.last_rx = jiffies;
1572         } else if (!is_multicast_ether_addr(hdr->addr1)) {
1573                 /*
1574                  * Mesh beacons will update last_rx when if they are found to
1575                  * match the current local configuration when processed.
1576                  */
1577                 sta->rx_stats.last_rx = jiffies;
1578                 if (ieee80211_is_data(hdr->frame_control))
1579                         sta->rx_stats.last_rate = sta_stats_encode_rate(status);
1580         }
1581
1582         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1583                 ieee80211_sta_rx_notify(rx->sdata, hdr);
1584
1585         sta->rx_stats.fragments++;
1586
1587         u64_stats_update_begin(&rx->sta->rx_stats.syncp);
1588         sta->rx_stats.bytes += rx->skb->len;
1589         u64_stats_update_end(&rx->sta->rx_stats.syncp);
1590
1591         if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
1592                 sta->rx_stats.last_signal = status->signal;
1593                 ewma_signal_add(&sta->rx_stats_avg.signal, -status->signal);
1594         }
1595
1596         if (status->chains) {
1597                 sta->rx_stats.chains = status->chains;
1598                 for (i = 0; i < ARRAY_SIZE(status->chain_signal); i++) {
1599                         int signal = status->chain_signal[i];
1600
1601                         if (!(status->chains & BIT(i)))
1602                                 continue;
1603
1604                         sta->rx_stats.chain_signal_last[i] = signal;
1605                         ewma_signal_add(&sta->rx_stats_avg.chain_signal[i],
1606                                         -signal);
1607                 }
1608         }
1609
1610         /*
1611          * Change STA power saving mode only at the end of a frame
1612          * exchange sequence.
1613          */
1614         if (!ieee80211_hw_check(&sta->local->hw, AP_LINK_PS) &&
1615             !ieee80211_has_morefrags(hdr->frame_control) &&
1616             !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1617             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1618              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1619             /* PM bit is only checked in frames where it isn't reserved,
1620              * in AP mode it's reserved in non-bufferable management frames
1621              * (cf. IEEE 802.11-2012 8.2.4.1.7 Power Management field)
1622              */
1623             (!ieee80211_is_mgmt(hdr->frame_control) ||
1624              ieee80211_is_bufferable_mmpdu(hdr->frame_control))) {
1625                 if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
1626                         if (!ieee80211_has_pm(hdr->frame_control))
1627                                 sta_ps_end(sta);
1628                 } else {
1629                         if (ieee80211_has_pm(hdr->frame_control))
1630                                 sta_ps_start(sta);
1631                 }
1632         }
1633
1634         /* mesh power save support */
1635         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
1636                 ieee80211_mps_rx_h_sta_process(sta, hdr);
1637
1638         /*
1639          * Drop (qos-)data::nullfunc frames silently, since they
1640          * are used only to control station power saving mode.
1641          */
1642         if (ieee80211_is_nullfunc(hdr->frame_control) ||
1643             ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1644                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1645
1646                 /*
1647                  * If we receive a 4-addr nullfunc frame from a STA
1648                  * that was not moved to a 4-addr STA vlan yet send
1649                  * the event to userspace and for older hostapd drop
1650                  * the frame to the monitor interface.
1651                  */
1652                 if (ieee80211_has_a4(hdr->frame_control) &&
1653                     (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1654                      (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1655                       !rx->sdata->u.vlan.sta))) {
1656                         if (!test_and_set_sta_flag(sta, WLAN_STA_4ADDR_EVENT))
1657                                 cfg80211_rx_unexpected_4addr_frame(
1658                                         rx->sdata->dev, sta->sta.addr,
1659                                         GFP_ATOMIC);
1660                         return RX_DROP_MONITOR;
1661                 }
1662                 /*
1663                  * Update counter and free packet here to avoid
1664                  * counting this as a dropped packed.
1665                  */
1666                 sta->rx_stats.packets++;
1667                 dev_kfree_skb(rx->skb);
1668                 return RX_QUEUED;
1669         }
1670
1671         return RX_CONTINUE;
1672 } /* ieee80211_rx_h_sta_process */
1673
1674 static ieee80211_rx_result debug_noinline
1675 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
1676 {
1677         struct sk_buff *skb = rx->skb;
1678         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1679         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1680         int keyidx;
1681         int hdrlen;
1682         ieee80211_rx_result result = RX_DROP_UNUSABLE;
1683         struct ieee80211_key *sta_ptk = NULL;
1684         int mmie_keyidx = -1;
1685         __le16 fc;
1686         const struct ieee80211_cipher_scheme *cs = NULL;
1687
1688         /*
1689          * Key selection 101
1690          *
1691          * There are four types of keys:
1692          *  - GTK (group keys)
1693          *  - IGTK (group keys for management frames)
1694          *  - PTK (pairwise keys)
1695          *  - STK (station-to-station pairwise keys)
1696          *
1697          * When selecting a key, we have to distinguish between multicast
1698          * (including broadcast) and unicast frames, the latter can only
1699          * use PTKs and STKs while the former always use GTKs and IGTKs.
1700          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
1701          * unicast frames can also use key indices like GTKs. Hence, if we
1702          * don't have a PTK/STK we check the key index for a WEP key.
1703          *
1704          * Note that in a regular BSS, multicast frames are sent by the
1705          * AP only, associated stations unicast the frame to the AP first
1706          * which then multicasts it on their behalf.
1707          *
1708          * There is also a slight problem in IBSS mode: GTKs are negotiated
1709          * with each station, that is something we don't currently handle.
1710          * The spec seems to expect that one negotiates the same key with
1711          * every station but there's no such requirement; VLANs could be
1712          * possible.
1713          */
1714
1715         /* start without a key */
1716         rx->key = NULL;
1717         fc = hdr->frame_control;
1718
1719         if (rx->sta) {
1720                 int keyid = rx->sta->ptk_idx;
1721
1722                 if (ieee80211_has_protected(fc) && rx->sta->cipher_scheme) {
1723                         cs = rx->sta->cipher_scheme;
1724                         keyid = ieee80211_get_cs_keyid(cs, rx->skb);
1725                         if (unlikely(keyid < 0))
1726                                 return RX_DROP_UNUSABLE;
1727                 }
1728                 sta_ptk = rcu_dereference(rx->sta->ptk[keyid]);
1729         }
1730
1731         if (!ieee80211_has_protected(fc))
1732                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
1733
1734         if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
1735                 rx->key = sta_ptk;
1736                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1737                     (status->flag & RX_FLAG_IV_STRIPPED))
1738                         return RX_CONTINUE;
1739                 /* Skip decryption if the frame is not protected. */
1740                 if (!ieee80211_has_protected(fc))
1741                         return RX_CONTINUE;
1742         } else if (mmie_keyidx >= 0) {
1743                 /* Broadcast/multicast robust management frame / BIP */
1744                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1745                     (status->flag & RX_FLAG_IV_STRIPPED))
1746                         return RX_CONTINUE;
1747
1748                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
1749                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
1750                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
1751                 if (rx->sta) {
1752                         if (ieee80211_is_group_privacy_action(skb) &&
1753                             test_sta_flag(rx->sta, WLAN_STA_MFP))
1754                                 return RX_DROP_MONITOR;
1755
1756                         rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
1757                 }
1758                 if (!rx->key)
1759                         rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
1760         } else if (!ieee80211_has_protected(fc)) {
1761                 /*
1762                  * The frame was not protected, so skip decryption. However, we
1763                  * need to set rx->key if there is a key that could have been
1764                  * used so that the frame may be dropped if encryption would
1765                  * have been expected.
1766                  */
1767                 struct ieee80211_key *key = NULL;
1768                 struct ieee80211_sub_if_data *sdata = rx->sdata;
1769                 int i;
1770
1771                 if (ieee80211_is_mgmt(fc) &&
1772                     is_multicast_ether_addr(hdr->addr1) &&
1773                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
1774                         rx->key = key;
1775                 else {
1776                         if (rx->sta) {
1777                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1778                                         key = rcu_dereference(rx->sta->gtk[i]);
1779                                         if (key)
1780                                                 break;
1781                                 }
1782                         }
1783                         if (!key) {
1784                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1785                                         key = rcu_dereference(sdata->keys[i]);
1786                                         if (key)
1787                                                 break;
1788                                 }
1789                         }
1790                         if (key)
1791                                 rx->key = key;
1792                 }
1793                 return RX_CONTINUE;
1794         } else {
1795                 u8 keyid;
1796
1797                 /*
1798                  * The device doesn't give us the IV so we won't be
1799                  * able to look up the key. That's ok though, we
1800                  * don't need to decrypt the frame, we just won't
1801                  * be able to keep statistics accurate.
1802                  * Except for key threshold notifications, should
1803                  * we somehow allow the driver to tell us which key
1804                  * the hardware used if this flag is set?
1805                  */
1806                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1807                     (status->flag & RX_FLAG_IV_STRIPPED))
1808                         return RX_CONTINUE;
1809
1810                 hdrlen = ieee80211_hdrlen(fc);
1811
1812                 if (cs) {
1813                         keyidx = ieee80211_get_cs_keyid(cs, rx->skb);
1814
1815                         if (unlikely(keyidx < 0))
1816                                 return RX_DROP_UNUSABLE;
1817                 } else {
1818                         if (rx->skb->len < 8 + hdrlen)
1819                                 return RX_DROP_UNUSABLE; /* TODO: count this? */
1820                         /*
1821                          * no need to call ieee80211_wep_get_keyidx,
1822                          * it verifies a bunch of things we've done already
1823                          */
1824                         skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
1825                         keyidx = keyid >> 6;
1826                 }
1827
1828                 /* check per-station GTK first, if multicast packet */
1829                 if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
1830                         rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
1831
1832                 /* if not found, try default key */
1833                 if (!rx->key) {
1834                         rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
1835
1836                         /*
1837                          * RSNA-protected unicast frames should always be
1838                          * sent with pairwise or station-to-station keys,
1839                          * but for WEP we allow using a key index as well.
1840                          */
1841                         if (rx->key &&
1842                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1843                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1844                             !is_multicast_ether_addr(hdr->addr1))
1845                                 rx->key = NULL;
1846                 }
1847         }
1848
1849         if (rx->key) {
1850                 if (unlikely(rx->key->flags & KEY_FLAG_TAINTED))
1851                         return RX_DROP_MONITOR;
1852
1853                 /* TODO: add threshold stuff again */
1854         } else {
1855                 return RX_DROP_MONITOR;
1856         }
1857
1858         switch (rx->key->conf.cipher) {
1859         case WLAN_CIPHER_SUITE_WEP40:
1860         case WLAN_CIPHER_SUITE_WEP104:
1861                 result = ieee80211_crypto_wep_decrypt(rx);
1862                 break;
1863         case WLAN_CIPHER_SUITE_TKIP:
1864                 result = ieee80211_crypto_tkip_decrypt(rx);
1865                 break;
1866         case WLAN_CIPHER_SUITE_CCMP:
1867                 result = ieee80211_crypto_ccmp_decrypt(
1868                         rx, IEEE80211_CCMP_MIC_LEN);
1869                 break;
1870         case WLAN_CIPHER_SUITE_CCMP_256:
1871                 result = ieee80211_crypto_ccmp_decrypt(
1872                         rx, IEEE80211_CCMP_256_MIC_LEN);
1873                 break;
1874         case WLAN_CIPHER_SUITE_AES_CMAC:
1875                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
1876                 break;
1877         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1878                 result = ieee80211_crypto_aes_cmac_256_decrypt(rx);
1879                 break;
1880         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1881         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1882                 result = ieee80211_crypto_aes_gmac_decrypt(rx);
1883                 break;
1884         case WLAN_CIPHER_SUITE_GCMP:
1885         case WLAN_CIPHER_SUITE_GCMP_256:
1886                 result = ieee80211_crypto_gcmp_decrypt(rx);
1887                 break;
1888         default:
1889                 result = ieee80211_crypto_hw_decrypt(rx);
1890         }
1891
1892         /* the hdr variable is invalid after the decrypt handlers */
1893
1894         /* either the frame has been decrypted or will be dropped */
1895         status->flag |= RX_FLAG_DECRYPTED;
1896
1897         return result;
1898 }
1899
1900 static inline struct ieee80211_fragment_entry *
1901 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1902                          unsigned int frag, unsigned int seq, int rx_queue,
1903                          struct sk_buff **skb)
1904 {
1905         struct ieee80211_fragment_entry *entry;
1906
1907         entry = &sdata->fragments[sdata->fragment_next++];
1908         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1909                 sdata->fragment_next = 0;
1910
1911         if (!skb_queue_empty(&entry->skb_list))
1912                 __skb_queue_purge(&entry->skb_list);
1913
1914         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1915         *skb = NULL;
1916         entry->first_frag_time = jiffies;
1917         entry->seq = seq;
1918         entry->rx_queue = rx_queue;
1919         entry->last_frag = frag;
1920         entry->check_sequential_pn = false;
1921         entry->extra_len = 0;
1922
1923         return entry;
1924 }
1925
1926 static inline struct ieee80211_fragment_entry *
1927 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1928                           unsigned int frag, unsigned int seq,
1929                           int rx_queue, struct ieee80211_hdr *hdr)
1930 {
1931         struct ieee80211_fragment_entry *entry;
1932         int i, idx;
1933
1934         idx = sdata->fragment_next;
1935         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1936                 struct ieee80211_hdr *f_hdr;
1937
1938                 idx--;
1939                 if (idx < 0)
1940                         idx = IEEE80211_FRAGMENT_MAX - 1;
1941
1942                 entry = &sdata->fragments[idx];
1943                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1944                     entry->rx_queue != rx_queue ||
1945                     entry->last_frag + 1 != frag)
1946                         continue;
1947
1948                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1949
1950                 /*
1951                  * Check ftype and addresses are equal, else check next fragment
1952                  */
1953                 if (((hdr->frame_control ^ f_hdr->frame_control) &
1954                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1955                     !ether_addr_equal(hdr->addr1, f_hdr->addr1) ||
1956                     !ether_addr_equal(hdr->addr2, f_hdr->addr2))
1957                         continue;
1958
1959                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1960                         __skb_queue_purge(&entry->skb_list);
1961                         continue;
1962                 }
1963                 return entry;
1964         }
1965
1966         return NULL;
1967 }
1968
1969 static ieee80211_rx_result debug_noinline
1970 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1971 {
1972         struct ieee80211_hdr *hdr;
1973         u16 sc;
1974         __le16 fc;
1975         unsigned int frag, seq;
1976         struct ieee80211_fragment_entry *entry;
1977         struct sk_buff *skb;
1978
1979         hdr = (struct ieee80211_hdr *)rx->skb->data;
1980         fc = hdr->frame_control;
1981
1982         if (ieee80211_is_ctl(fc))
1983                 return RX_CONTINUE;
1984
1985         sc = le16_to_cpu(hdr->seq_ctrl);
1986         frag = sc & IEEE80211_SCTL_FRAG;
1987
1988         if (is_multicast_ether_addr(hdr->addr1)) {
1989                 I802_DEBUG_INC(rx->local->dot11MulticastReceivedFrameCount);
1990                 goto out_no_led;
1991         }
1992
1993         if (likely(!ieee80211_has_morefrags(fc) && frag == 0))
1994                 goto out;
1995
1996         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1997
1998         if (skb_linearize(rx->skb))
1999                 return RX_DROP_UNUSABLE;
2000
2001         /*
2002          *  skb_linearize() might change the skb->data and
2003          *  previously cached variables (in this case, hdr) need to
2004          *  be refreshed with the new data.
2005          */
2006         hdr = (struct ieee80211_hdr *)rx->skb->data;
2007         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
2008
2009         if (frag == 0) {
2010                 /* This is the first fragment of a new frame. */
2011                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
2012                                                  rx->seqno_idx, &(rx->skb));
2013                 if (rx->key &&
2014                     (rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP ||
2015                      rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP_256 ||
2016                      rx->key->conf.cipher == WLAN_CIPHER_SUITE_GCMP ||
2017                      rx->key->conf.cipher == WLAN_CIPHER_SUITE_GCMP_256) &&
2018                     ieee80211_has_protected(fc)) {
2019                         int queue = rx->security_idx;
2020
2021                         /* Store CCMP/GCMP PN so that we can verify that the
2022                          * next fragment has a sequential PN value.
2023                          */
2024                         entry->check_sequential_pn = true;
2025                         memcpy(entry->last_pn,
2026                                rx->key->u.ccmp.rx_pn[queue],
2027                                IEEE80211_CCMP_PN_LEN);
2028                         BUILD_BUG_ON(offsetof(struct ieee80211_key,
2029                                               u.ccmp.rx_pn) !=
2030                                      offsetof(struct ieee80211_key,
2031                                               u.gcmp.rx_pn));
2032                         BUILD_BUG_ON(sizeof(rx->key->u.ccmp.rx_pn[queue]) !=
2033                                      sizeof(rx->key->u.gcmp.rx_pn[queue]));
2034                         BUILD_BUG_ON(IEEE80211_CCMP_PN_LEN !=
2035                                      IEEE80211_GCMP_PN_LEN);
2036                 }
2037                 return RX_QUEUED;
2038         }
2039
2040         /* This is a fragment for a frame that should already be pending in
2041          * fragment cache. Add this fragment to the end of the pending entry.
2042          */
2043         entry = ieee80211_reassemble_find(rx->sdata, frag, seq,
2044                                           rx->seqno_idx, hdr);
2045         if (!entry) {
2046                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
2047                 return RX_DROP_MONITOR;
2048         }
2049
2050         /* "The receiver shall discard MSDUs and MMPDUs whose constituent
2051          *  MPDU PN values are not incrementing in steps of 1."
2052          * see IEEE P802.11-REVmc/D5.0, 12.5.3.4.4, item d (for CCMP)
2053          * and IEEE P802.11-REVmc/D5.0, 12.5.5.4.4, item d (for GCMP)
2054          */
2055         if (entry->check_sequential_pn) {
2056                 int i;
2057                 u8 pn[IEEE80211_CCMP_PN_LEN], *rpn;
2058                 int queue;
2059
2060                 if (!rx->key ||
2061                     (rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP &&
2062                      rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP_256 &&
2063                      rx->key->conf.cipher != WLAN_CIPHER_SUITE_GCMP &&
2064                      rx->key->conf.cipher != WLAN_CIPHER_SUITE_GCMP_256))
2065                         return RX_DROP_UNUSABLE;
2066                 memcpy(pn, entry->last_pn, IEEE80211_CCMP_PN_LEN);
2067                 for (i = IEEE80211_CCMP_PN_LEN - 1; i >= 0; i--) {
2068                         pn[i]++;
2069                         if (pn[i])
2070                                 break;
2071                 }
2072                 queue = rx->security_idx;
2073                 rpn = rx->key->u.ccmp.rx_pn[queue];
2074                 if (memcmp(pn, rpn, IEEE80211_CCMP_PN_LEN))
2075                         return RX_DROP_UNUSABLE;
2076                 memcpy(entry->last_pn, pn, IEEE80211_CCMP_PN_LEN);
2077         }
2078
2079         skb_pull(rx->skb, ieee80211_hdrlen(fc));
2080         __skb_queue_tail(&entry->skb_list, rx->skb);
2081         entry->last_frag = frag;
2082         entry->extra_len += rx->skb->len;
2083         if (ieee80211_has_morefrags(fc)) {
2084                 rx->skb = NULL;
2085                 return RX_QUEUED;
2086         }
2087
2088         rx->skb = __skb_dequeue(&entry->skb_list);
2089         if (skb_tailroom(rx->skb) < entry->extra_len) {
2090                 I802_DEBUG_INC(rx->local->rx_expand_skb_head_defrag);
2091                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
2092                                               GFP_ATOMIC))) {
2093                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
2094                         __skb_queue_purge(&entry->skb_list);
2095                         return RX_DROP_UNUSABLE;
2096                 }
2097         }
2098         while ((skb = __skb_dequeue(&entry->skb_list))) {
2099                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
2100                 dev_kfree_skb(skb);
2101         }
2102
2103  out:
2104         ieee80211_led_rx(rx->local);
2105  out_no_led:
2106         if (rx->sta)
2107                 rx->sta->rx_stats.packets++;
2108         return RX_CONTINUE;
2109 }
2110
2111 static int ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
2112 {
2113         if (unlikely(!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_AUTHORIZED)))
2114                 return -EACCES;
2115
2116         return 0;
2117 }
2118
2119 static int ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
2120 {
2121         struct sk_buff *skb = rx->skb;
2122         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2123
2124         /*
2125          * Pass through unencrypted frames if the hardware has
2126          * decrypted them already.
2127          */
2128         if (status->flag & RX_FLAG_DECRYPTED)
2129                 return 0;
2130
2131         /* Drop unencrypted frames if key is set. */
2132         if (unlikely(!ieee80211_has_protected(fc) &&
2133                      !ieee80211_is_nullfunc(fc) &&
2134                      ieee80211_is_data(fc) && rx->key))
2135                 return -EACCES;
2136
2137         return 0;
2138 }
2139
2140 static int ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
2141 {
2142         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2143         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2144         __le16 fc = hdr->frame_control;
2145
2146         /*
2147          * Pass through unencrypted frames if the hardware has
2148          * decrypted them already.
2149          */
2150         if (status->flag & RX_FLAG_DECRYPTED)
2151                 return 0;
2152
2153         if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) {
2154                 if (unlikely(!ieee80211_has_protected(fc) &&
2155                              ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
2156                              rx->key)) {
2157                         if (ieee80211_is_deauth(fc) ||
2158                             ieee80211_is_disassoc(fc))
2159                                 cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
2160                                                              rx->skb->data,
2161                                                              rx->skb->len);
2162                         return -EACCES;
2163                 }
2164                 /* BIP does not use Protected field, so need to check MMIE */
2165                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
2166                              ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
2167                         if (ieee80211_is_deauth(fc) ||
2168                             ieee80211_is_disassoc(fc))
2169                                 cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
2170                                                              rx->skb->data,
2171                                                              rx->skb->len);
2172                         return -EACCES;
2173                 }
2174                 /*
2175                  * When using MFP, Action frames are not allowed prior to
2176                  * having configured keys.
2177                  */
2178                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
2179                              ieee80211_is_robust_mgmt_frame(rx->skb)))
2180                         return -EACCES;
2181         }
2182
2183         return 0;
2184 }
2185
2186 static int
2187 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx, bool *port_control)
2188 {
2189         struct ieee80211_sub_if_data *sdata = rx->sdata;
2190         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2191         bool check_port_control = false;
2192         struct ethhdr *ehdr;
2193         int ret;
2194
2195         *port_control = false;
2196         if (ieee80211_has_a4(hdr->frame_control) &&
2197             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
2198                 return -1;
2199
2200         if (sdata->vif.type == NL80211_IFTYPE_STATION &&
2201             !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) {
2202
2203                 if (!sdata->u.mgd.use_4addr)
2204                         return -1;
2205                 else
2206                         check_port_control = true;
2207         }
2208
2209         if (is_multicast_ether_addr(hdr->addr1) &&
2210             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta)
2211                 return -1;
2212
2213         ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
2214         if (ret < 0)
2215                 return ret;
2216
2217         ehdr = (struct ethhdr *) rx->skb->data;
2218         if (ehdr->h_proto == rx->sdata->control_port_protocol)
2219                 *port_control = true;
2220         else if (check_port_control)
2221                 return -1;
2222
2223         return 0;
2224 }
2225
2226 /*
2227  * requires that rx->skb is a frame with ethernet header
2228  */
2229 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
2230 {
2231         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
2232                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
2233         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
2234
2235         /*
2236          * Allow EAPOL frames to us/the PAE group address regardless
2237          * of whether the frame was encrypted or not.
2238          */
2239         if (ehdr->h_proto == rx->sdata->control_port_protocol &&
2240             (ether_addr_equal(ehdr->h_dest, rx->sdata->vif.addr) ||
2241              ether_addr_equal(ehdr->h_dest, pae_group_addr)))
2242                 return true;
2243
2244         if (ieee80211_802_1x_port_control(rx) ||
2245             ieee80211_drop_unencrypted(rx, fc))
2246                 return false;
2247
2248         return true;
2249 }
2250
2251 /*
2252  * requires that rx->skb is a frame with ethernet header
2253  */
2254 static void
2255 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
2256 {
2257         struct ieee80211_sub_if_data *sdata = rx->sdata;
2258         struct net_device *dev = sdata->dev;
2259         struct sk_buff *skb, *xmit_skb;
2260         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
2261         struct sta_info *dsta;
2262
2263         skb = rx->skb;
2264         xmit_skb = NULL;
2265
2266         ieee80211_rx_stats(dev, skb->len);
2267
2268         if (rx->sta) {
2269                 /* The seqno index has the same property as needed
2270                  * for the rx_msdu field, i.e. it is IEEE80211_NUM_TIDS
2271                  * for non-QoS-data frames. Here we know it's a data
2272                  * frame, so count MSDUs.
2273                  */
2274                 u64_stats_update_begin(&rx->sta->rx_stats.syncp);
2275                 rx->sta->rx_stats.msdu[rx->seqno_idx]++;
2276                 u64_stats_update_end(&rx->sta->rx_stats.syncp);
2277         }
2278
2279         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
2280              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
2281             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
2282             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
2283                 if (is_multicast_ether_addr(ehdr->h_dest) &&
2284                     ieee80211_vif_get_num_mcast_if(sdata) != 0) {
2285                         /*
2286                          * send multicast frames both to higher layers in
2287                          * local net stack and back to the wireless medium
2288                          */
2289                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
2290                         if (!xmit_skb)
2291                                 net_info_ratelimited("%s: failed to clone multicast frame\n",
2292                                                     dev->name);
2293                 } else if (!is_multicast_ether_addr(ehdr->h_dest)) {
2294                         dsta = sta_info_get(sdata, skb->data);
2295                         if (dsta) {
2296                                 /*
2297                                  * The destination station is associated to
2298                                  * this AP (in this VLAN), so send the frame
2299                                  * directly to it and do not pass it to local
2300                                  * net stack.
2301                                  */
2302                                 xmit_skb = skb;
2303                                 skb = NULL;
2304                         }
2305                 }
2306         }
2307
2308 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
2309         if (skb) {
2310                 /* 'align' will only take the values 0 or 2 here since all
2311                  * frames are required to be aligned to 2-byte boundaries
2312                  * when being passed to mac80211; the code here works just
2313                  * as well if that isn't true, but mac80211 assumes it can
2314                  * access fields as 2-byte aligned (e.g. for ether_addr_equal)
2315                  */
2316                 int align;
2317
2318                 align = (unsigned long)(skb->data + sizeof(struct ethhdr)) & 3;
2319                 if (align) {
2320                         if (WARN_ON(skb_headroom(skb) < 3)) {
2321                                 dev_kfree_skb(skb);
2322                                 skb = NULL;
2323                         } else {
2324                                 u8 *data = skb->data;
2325                                 size_t len = skb_headlen(skb);
2326                                 skb->data -= align;
2327                                 memmove(skb->data, data, len);
2328                                 skb_set_tail_pointer(skb, len);
2329                         }
2330                 }
2331         }
2332 #endif
2333
2334         if (skb) {
2335                 /* deliver to local stack */
2336                 skb->protocol = eth_type_trans(skb, dev);
2337                 memset(skb->cb, 0, sizeof(skb->cb));
2338                 if (rx->napi)
2339                         napi_gro_receive(rx->napi, skb);
2340                 else
2341                         netif_receive_skb(skb);
2342         }
2343
2344         if (xmit_skb) {
2345                 /*
2346                  * Send to wireless media and increase priority by 256 to
2347                  * keep the received priority instead of reclassifying
2348                  * the frame (see cfg80211_classify8021d).
2349                  */
2350                 xmit_skb->priority += 256;
2351                 xmit_skb->protocol = htons(ETH_P_802_3);
2352                 skb_reset_network_header(xmit_skb);
2353                 skb_reset_mac_header(xmit_skb);
2354                 dev_queue_xmit(xmit_skb);
2355         }
2356 }
2357
2358 static ieee80211_rx_result debug_noinline
2359 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
2360 {
2361         struct net_device *dev = rx->sdata->dev;
2362         struct sk_buff *skb = rx->skb;
2363         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2364         __le16 fc = hdr->frame_control;
2365         struct sk_buff_head frame_list;
2366         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2367         struct ethhdr ethhdr;
2368         const u8 *check_da = ethhdr.h_dest, *check_sa = ethhdr.h_source;
2369
2370         if (unlikely(!ieee80211_is_data(fc)))
2371                 return RX_CONTINUE;
2372
2373         if (unlikely(!ieee80211_is_data_present(fc)))
2374                 return RX_DROP_MONITOR;
2375
2376         if (!(status->rx_flags & IEEE80211_RX_AMSDU))
2377                 return RX_CONTINUE;
2378
2379         if (unlikely(ieee80211_has_a4(hdr->frame_control))) {
2380                 switch (rx->sdata->vif.type) {
2381                 case NL80211_IFTYPE_AP_VLAN:
2382                         if (!rx->sdata->u.vlan.sta)
2383                                 return RX_DROP_UNUSABLE;
2384                         break;
2385                 case NL80211_IFTYPE_STATION:
2386                         if (!rx->sdata->u.mgd.use_4addr)
2387                                 return RX_DROP_UNUSABLE;
2388                         break;
2389                 default:
2390                         return RX_DROP_UNUSABLE;
2391                 }
2392                 check_da = NULL;
2393                 check_sa = NULL;
2394         } else switch (rx->sdata->vif.type) {
2395                 case NL80211_IFTYPE_AP:
2396                 case NL80211_IFTYPE_AP_VLAN:
2397                         check_da = NULL;
2398                         break;
2399                 case NL80211_IFTYPE_STATION:
2400                         if (!rx->sta ||
2401                             !test_sta_flag(rx->sta, WLAN_STA_TDLS_PEER))
2402                                 check_sa = NULL;
2403                         break;
2404                 case NL80211_IFTYPE_MESH_POINT:
2405                         check_sa = NULL;
2406                         break;
2407                 default:
2408                         break;
2409         }
2410
2411         if (is_multicast_ether_addr(hdr->addr1))
2412                 return RX_DROP_UNUSABLE;
2413
2414         skb->dev = dev;
2415         __skb_queue_head_init(&frame_list);
2416
2417         if (ieee80211_data_to_8023_exthdr(skb, &ethhdr,
2418                                           rx->sdata->vif.addr,
2419                                           rx->sdata->vif.type))
2420                 return RX_DROP_UNUSABLE;
2421
2422         ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
2423                                  rx->sdata->vif.type,
2424                                  rx->local->hw.extra_tx_headroom,
2425                                  check_da, check_sa);
2426
2427         while (!skb_queue_empty(&frame_list)) {
2428                 rx->skb = __skb_dequeue(&frame_list);
2429
2430                 if (!ieee80211_frame_allowed(rx, fc)) {
2431                         dev_kfree_skb(rx->skb);
2432                         continue;
2433                 }
2434
2435                 ieee80211_deliver_skb(rx);
2436         }
2437
2438         return RX_QUEUED;
2439 }
2440
2441 #ifdef CONFIG_MAC80211_MESH
2442 static ieee80211_rx_result
2443 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
2444 {
2445         struct ieee80211_hdr *fwd_hdr, *hdr;
2446         struct ieee80211_tx_info *info;
2447         struct ieee80211s_hdr *mesh_hdr;
2448         struct sk_buff *skb = rx->skb, *fwd_skb;
2449         struct ieee80211_local *local = rx->local;
2450         struct ieee80211_sub_if_data *sdata = rx->sdata;
2451         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
2452         u16 ac, q, hdrlen;
2453
2454         hdr = (struct ieee80211_hdr *) skb->data;
2455         hdrlen = ieee80211_hdrlen(hdr->frame_control);
2456
2457         /* make sure fixed part of mesh header is there, also checks skb len */
2458         if (!pskb_may_pull(rx->skb, hdrlen + 6))
2459                 return RX_DROP_MONITOR;
2460
2461         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2462
2463         /* make sure full mesh header is there, also checks skb len */
2464         if (!pskb_may_pull(rx->skb,
2465                            hdrlen + ieee80211_get_mesh_hdrlen(mesh_hdr)))
2466                 return RX_DROP_MONITOR;
2467
2468         /* reload pointers */
2469         hdr = (struct ieee80211_hdr *) skb->data;
2470         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2471
2472         if (ieee80211_drop_unencrypted(rx, hdr->frame_control))
2473                 return RX_DROP_MONITOR;
2474
2475         /* frame is in RMC, don't forward */
2476         if (ieee80211_is_data(hdr->frame_control) &&
2477             is_multicast_ether_addr(hdr->addr1) &&
2478             mesh_rmc_check(rx->sdata, hdr->addr3, mesh_hdr))
2479                 return RX_DROP_MONITOR;
2480
2481         if (!ieee80211_is_data(hdr->frame_control))
2482                 return RX_CONTINUE;
2483
2484         if (!mesh_hdr->ttl)
2485                 return RX_DROP_MONITOR;
2486
2487         if (mesh_hdr->flags & MESH_FLAGS_AE) {
2488                 struct mesh_path *mppath;
2489                 char *proxied_addr;
2490                 char *mpp_addr;
2491
2492                 if (is_multicast_ether_addr(hdr->addr1)) {
2493                         mpp_addr = hdr->addr3;
2494                         proxied_addr = mesh_hdr->eaddr1;
2495                 } else if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6) {
2496                         /* has_a4 already checked in ieee80211_rx_mesh_check */
2497                         mpp_addr = hdr->addr4;
2498                         proxied_addr = mesh_hdr->eaddr2;
2499                 } else {
2500                         return RX_DROP_MONITOR;
2501                 }
2502
2503                 rcu_read_lock();
2504                 mppath = mpp_path_lookup(sdata, proxied_addr);
2505                 if (!mppath) {
2506                         mpp_path_add(sdata, proxied_addr, mpp_addr);
2507                 } else {
2508                         spin_lock_bh(&mppath->state_lock);
2509                         if (!ether_addr_equal(mppath->mpp, mpp_addr))
2510                                 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
2511                         mppath->exp_time = jiffies;
2512                         spin_unlock_bh(&mppath->state_lock);
2513                 }
2514                 rcu_read_unlock();
2515         }
2516
2517         /* Frame has reached destination.  Don't forward */
2518         if (!is_multicast_ether_addr(hdr->addr1) &&
2519             ether_addr_equal(sdata->vif.addr, hdr->addr3))
2520                 return RX_CONTINUE;
2521
2522         ac = ieee80211_select_queue_80211(sdata, skb, hdr);
2523         q = sdata->vif.hw_queue[ac];
2524         if (ieee80211_queue_stopped(&local->hw, q)) {
2525                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion);
2526                 return RX_DROP_MONITOR;
2527         }
2528         skb_set_queue_mapping(skb, q);
2529
2530         if (!--mesh_hdr->ttl) {
2531                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
2532                 goto out;
2533         }
2534
2535         if (!ifmsh->mshcfg.dot11MeshForwarding)
2536                 goto out;
2537
2538         fwd_skb = skb_copy_expand(skb, local->tx_headroom +
2539                                        sdata->encrypt_headroom, 0, GFP_ATOMIC);
2540         if (!fwd_skb) {
2541                 net_info_ratelimited("%s: failed to clone mesh frame\n",
2542                                     sdata->name);
2543                 goto out;
2544         }
2545
2546         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
2547         fwd_hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_RETRY);
2548         info = IEEE80211_SKB_CB(fwd_skb);
2549         memset(info, 0, sizeof(*info));
2550         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
2551         info->control.vif = &rx->sdata->vif;
2552         info->control.jiffies = jiffies;
2553         if (is_multicast_ether_addr(fwd_hdr->addr1)) {
2554                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_mcast);
2555                 memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
2556                 /* update power mode indication when forwarding */
2557                 ieee80211_mps_set_frame_flags(sdata, NULL, fwd_hdr);
2558         } else if (!mesh_nexthop_lookup(sdata, fwd_skb)) {
2559                 /* mesh power mode flags updated in mesh_nexthop_lookup */
2560                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_unicast);
2561         } else {
2562                 /* unable to resolve next hop */
2563                 mesh_path_error_tx(sdata, ifmsh->mshcfg.element_ttl,
2564                                    fwd_hdr->addr3, 0,
2565                                    WLAN_REASON_MESH_PATH_NOFORWARD,
2566                                    fwd_hdr->addr2);
2567                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_no_route);
2568                 kfree_skb(fwd_skb);
2569                 return RX_DROP_MONITOR;
2570         }
2571
2572         IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_frames);
2573         ieee80211_add_pending_skb(local, fwd_skb);
2574  out:
2575         if (is_multicast_ether_addr(hdr->addr1))
2576                 return RX_CONTINUE;
2577         return RX_DROP_MONITOR;
2578 }
2579 #endif
2580
2581 static ieee80211_rx_result debug_noinline
2582 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
2583 {
2584         struct ieee80211_sub_if_data *sdata = rx->sdata;
2585         struct ieee80211_local *local = rx->local;
2586         struct net_device *dev = sdata->dev;
2587         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2588         __le16 fc = hdr->frame_control;
2589         bool port_control;
2590         int err;
2591
2592         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
2593                 return RX_CONTINUE;
2594
2595         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
2596                 return RX_DROP_MONITOR;
2597
2598         /*
2599          * Send unexpected-4addr-frame event to hostapd. For older versions,
2600          * also drop the frame to cooked monitor interfaces.
2601          */
2602         if (ieee80211_has_a4(hdr->frame_control) &&
2603             sdata->vif.type == NL80211_IFTYPE_AP) {
2604                 if (rx->sta &&
2605                     !test_and_set_sta_flag(rx->sta, WLAN_STA_4ADDR_EVENT))
2606                         cfg80211_rx_unexpected_4addr_frame(
2607                                 rx->sdata->dev, rx->sta->sta.addr, GFP_ATOMIC);
2608                 return RX_DROP_MONITOR;
2609         }
2610
2611         err = __ieee80211_data_to_8023(rx, &port_control);
2612         if (unlikely(err))
2613                 return RX_DROP_UNUSABLE;
2614
2615         if (!ieee80211_frame_allowed(rx, fc))
2616                 return RX_DROP_MONITOR;
2617
2618         /* directly handle TDLS channel switch requests/responses */
2619         if (unlikely(((struct ethhdr *)rx->skb->data)->h_proto ==
2620                                                 cpu_to_be16(ETH_P_TDLS))) {
2621                 struct ieee80211_tdls_data *tf = (void *)rx->skb->data;
2622
2623                 if (pskb_may_pull(rx->skb,
2624                                   offsetof(struct ieee80211_tdls_data, u)) &&
2625                     tf->payload_type == WLAN_TDLS_SNAP_RFTYPE &&
2626                     tf->category == WLAN_CATEGORY_TDLS &&
2627                     (tf->action_code == WLAN_TDLS_CHANNEL_SWITCH_REQUEST ||
2628                      tf->action_code == WLAN_TDLS_CHANNEL_SWITCH_RESPONSE)) {
2629                         skb_queue_tail(&local->skb_queue_tdls_chsw, rx->skb);
2630                         schedule_work(&local->tdls_chsw_work);
2631                         if (rx->sta)
2632                                 rx->sta->rx_stats.packets++;
2633
2634                         return RX_QUEUED;
2635                 }
2636         }
2637
2638         if (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
2639             unlikely(port_control) && sdata->bss) {
2640                 sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
2641                                      u.ap);
2642                 dev = sdata->dev;
2643                 rx->sdata = sdata;
2644         }
2645
2646         rx->skb->dev = dev;
2647
2648         if (!ieee80211_hw_check(&local->hw, SUPPORTS_DYNAMIC_PS) &&
2649             local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
2650             !is_multicast_ether_addr(
2651                     ((struct ethhdr *)rx->skb->data)->h_dest) &&
2652             (!local->scanning &&
2653              !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state)))
2654                 mod_timer(&local->dynamic_ps_timer, jiffies +
2655                           msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
2656
2657         ieee80211_deliver_skb(rx);
2658
2659         return RX_QUEUED;
2660 }
2661
2662 static ieee80211_rx_result debug_noinline
2663 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
2664 {
2665         struct sk_buff *skb = rx->skb;
2666         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
2667         struct tid_ampdu_rx *tid_agg_rx;
2668         u16 start_seq_num;
2669         u16 tid;
2670
2671         if (likely(!ieee80211_is_ctl(bar->frame_control)))
2672                 return RX_CONTINUE;
2673
2674         if (ieee80211_is_back_req(bar->frame_control)) {
2675                 struct {
2676                         __le16 control, start_seq_num;
2677                 } __packed bar_data;
2678                 struct ieee80211_event event = {
2679                         .type = BAR_RX_EVENT,
2680                 };
2681
2682                 if (!rx->sta)
2683                         return RX_DROP_MONITOR;
2684
2685                 if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
2686                                   &bar_data, sizeof(bar_data)))
2687                         return RX_DROP_MONITOR;
2688
2689                 tid = le16_to_cpu(bar_data.control) >> 12;
2690
2691                 if (!test_bit(tid, rx->sta->ampdu_mlme.agg_session_valid) &&
2692                     !test_and_set_bit(tid, rx->sta->ampdu_mlme.unexpected_agg))
2693                         ieee80211_send_delba(rx->sdata, rx->sta->sta.addr, tid,
2694                                              WLAN_BACK_RECIPIENT,
2695                                              WLAN_REASON_QSTA_REQUIRE_SETUP);
2696
2697                 tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
2698                 if (!tid_agg_rx)
2699                         return RX_DROP_MONITOR;
2700
2701                 start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
2702                 event.u.ba.tid = tid;
2703                 event.u.ba.ssn = start_seq_num;
2704                 event.u.ba.sta = &rx->sta->sta;
2705
2706                 /* reset session timer */
2707                 if (tid_agg_rx->timeout)
2708                         mod_timer(&tid_agg_rx->session_timer,
2709                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
2710
2711                 spin_lock(&tid_agg_rx->reorder_lock);
2712                 /* release stored frames up to start of BAR */
2713                 ieee80211_release_reorder_frames(rx->sdata, tid_agg_rx,
2714                                                  start_seq_num, frames);
2715                 spin_unlock(&tid_agg_rx->reorder_lock);
2716
2717                 drv_event_callback(rx->local, rx->sdata, &event);
2718
2719                 kfree_skb(skb);
2720                 return RX_QUEUED;
2721         }
2722
2723         /*
2724          * After this point, we only want management frames,
2725          * so we can drop all remaining control frames to
2726          * cooked monitor interfaces.
2727          */
2728         return RX_DROP_MONITOR;
2729 }
2730
2731 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
2732                                            struct ieee80211_mgmt *mgmt,
2733                                            size_t len)
2734 {
2735         struct ieee80211_local *local = sdata->local;
2736         struct sk_buff *skb;
2737         struct ieee80211_mgmt *resp;
2738
2739         if (!ether_addr_equal(mgmt->da, sdata->vif.addr)) {
2740                 /* Not to own unicast address */
2741                 return;
2742         }
2743
2744         if (!ether_addr_equal(mgmt->sa, sdata->u.mgd.bssid) ||
2745             !ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid)) {
2746                 /* Not from the current AP or not associated yet. */
2747                 return;
2748         }
2749
2750         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
2751                 /* Too short SA Query request frame */
2752                 return;
2753         }
2754
2755         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
2756         if (skb == NULL)
2757                 return;
2758
2759         skb_reserve(skb, local->hw.extra_tx_headroom);
2760         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
2761         memset(resp, 0, 24);
2762         memcpy(resp->da, mgmt->sa, ETH_ALEN);
2763         memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
2764         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
2765         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2766                                           IEEE80211_STYPE_ACTION);
2767         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
2768         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
2769         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
2770         memcpy(resp->u.action.u.sa_query.trans_id,
2771                mgmt->u.action.u.sa_query.trans_id,
2772                WLAN_SA_QUERY_TR_ID_LEN);
2773
2774         ieee80211_tx_skb(sdata, skb);
2775 }
2776
2777 static ieee80211_rx_result debug_noinline
2778 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
2779 {
2780         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2781         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2782
2783         /*
2784          * From here on, look only at management frames.
2785          * Data and control frames are already handled,
2786          * and unknown (reserved) frames are useless.
2787          */
2788         if (rx->skb->len < 24)
2789                 return RX_DROP_MONITOR;
2790
2791         if (!ieee80211_is_mgmt(mgmt->frame_control))
2792                 return RX_DROP_MONITOR;
2793
2794         if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
2795             ieee80211_is_beacon(mgmt->frame_control) &&
2796             !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) {
2797                 int sig = 0;
2798
2799                 if (ieee80211_hw_check(&rx->local->hw, SIGNAL_DBM))
2800                         sig = status->signal;
2801
2802                 cfg80211_report_obss_beacon(rx->local->hw.wiphy,
2803                                             rx->skb->data, rx->skb->len,
2804                                             status->freq, sig);
2805                 rx->flags |= IEEE80211_RX_BEACON_REPORTED;
2806         }
2807
2808         if (ieee80211_drop_unencrypted_mgmt(rx))
2809                 return RX_DROP_UNUSABLE;
2810
2811         return RX_CONTINUE;
2812 }
2813
2814 static ieee80211_rx_result debug_noinline
2815 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2816 {
2817         struct ieee80211_local *local = rx->local;
2818         struct ieee80211_sub_if_data *sdata = rx->sdata;
2819         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2820         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2821         int len = rx->skb->len;
2822
2823         if (!ieee80211_is_action(mgmt->frame_control))
2824                 return RX_CONTINUE;
2825
2826         /* drop too small frames */
2827         if (len < IEEE80211_MIN_ACTION_SIZE)
2828                 return RX_DROP_UNUSABLE;
2829
2830         if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC &&
2831             mgmt->u.action.category != WLAN_CATEGORY_SELF_PROTECTED &&
2832             mgmt->u.action.category != WLAN_CATEGORY_SPECTRUM_MGMT)
2833                 return RX_DROP_UNUSABLE;
2834
2835         switch (mgmt->u.action.category) {
2836         case WLAN_CATEGORY_HT:
2837                 /* reject HT action frames from stations not supporting HT */
2838                 if (!rx->sta->sta.ht_cap.ht_supported)
2839                         goto invalid;
2840
2841                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2842                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2843                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2844                     sdata->vif.type != NL80211_IFTYPE_AP &&
2845                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2846                         break;
2847
2848                 /* verify action & smps_control/chanwidth are present */
2849                 if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2850                         goto invalid;
2851
2852                 switch (mgmt->u.action.u.ht_smps.action) {
2853                 case WLAN_HT_ACTION_SMPS: {
2854                         struct ieee80211_supported_band *sband;
2855                         enum ieee80211_smps_mode smps_mode;
2856
2857                         /* convert to HT capability */
2858                         switch (mgmt->u.action.u.ht_smps.smps_control) {
2859                         case WLAN_HT_SMPS_CONTROL_DISABLED:
2860                                 smps_mode = IEEE80211_SMPS_OFF;
2861                                 break;
2862                         case WLAN_HT_SMPS_CONTROL_STATIC:
2863                                 smps_mode = IEEE80211_SMPS_STATIC;
2864                                 break;
2865                         case WLAN_HT_SMPS_CONTROL_DYNAMIC:
2866                                 smps_mode = IEEE80211_SMPS_DYNAMIC;
2867                                 break;
2868                         default:
2869                                 goto invalid;
2870                         }
2871
2872                         /* if no change do nothing */
2873                         if (rx->sta->sta.smps_mode == smps_mode)
2874                                 goto handled;
2875                         rx->sta->sta.smps_mode = smps_mode;
2876
2877                         sband = rx->local->hw.wiphy->bands[status->band];
2878
2879                         rate_control_rate_update(local, sband, rx->sta,
2880                                                  IEEE80211_RC_SMPS_CHANGED);
2881                         goto handled;
2882                 }
2883                 case WLAN_HT_ACTION_NOTIFY_CHANWIDTH: {
2884                         struct ieee80211_supported_band *sband;
2885                         u8 chanwidth = mgmt->u.action.u.ht_notify_cw.chanwidth;
2886                         enum ieee80211_sta_rx_bandwidth max_bw, new_bw;
2887
2888                         /* If it doesn't support 40 MHz it can't change ... */
2889                         if (!(rx->sta->sta.ht_cap.cap &
2890                                         IEEE80211_HT_CAP_SUP_WIDTH_20_40))
2891                                 goto handled;
2892
2893                         if (chanwidth == IEEE80211_HT_CHANWIDTH_20MHZ)
2894                                 max_bw = IEEE80211_STA_RX_BW_20;
2895                         else
2896                                 max_bw = ieee80211_sta_cap_rx_bw(rx->sta);
2897
2898                         /* set cur_max_bandwidth and recalc sta bw */
2899                         rx->sta->cur_max_bandwidth = max_bw;
2900                         new_bw = ieee80211_sta_cur_vht_bw(rx->sta);
2901
2902                         if (rx->sta->sta.bandwidth == new_bw)
2903                                 goto handled;
2904
2905                         rx->sta->sta.bandwidth = new_bw;
2906                         sband = rx->local->hw.wiphy->bands[status->band];
2907
2908                         rate_control_rate_update(local, sband, rx->sta,
2909                                                  IEEE80211_RC_BW_CHANGED);
2910                         goto handled;
2911                 }
2912                 default:
2913                         goto invalid;
2914                 }
2915
2916                 break;
2917         case WLAN_CATEGORY_PUBLIC:
2918                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2919                         goto invalid;
2920                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2921                         break;
2922                 if (!rx->sta)
2923                         break;
2924                 if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
2925                         break;
2926                 if (mgmt->u.action.u.ext_chan_switch.action_code !=
2927                                 WLAN_PUB_ACTION_EXT_CHANSW_ANN)
2928                         break;
2929                 if (len < offsetof(struct ieee80211_mgmt,
2930                                    u.action.u.ext_chan_switch.variable))
2931                         goto invalid;
2932                 goto queue;
2933         case WLAN_CATEGORY_VHT:
2934                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2935                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2936                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2937                     sdata->vif.type != NL80211_IFTYPE_AP &&
2938                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2939                         break;
2940
2941                 /* verify action code is present */
2942                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2943                         goto invalid;
2944
2945                 switch (mgmt->u.action.u.vht_opmode_notif.action_code) {
2946                 case WLAN_VHT_ACTION_OPMODE_NOTIF: {
2947                         /* verify opmode is present */
2948                         if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2949                                 goto invalid;
2950                         goto queue;
2951                 }
2952                 case WLAN_VHT_ACTION_GROUPID_MGMT: {
2953                         if (len < IEEE80211_MIN_ACTION_SIZE + 25)
2954                                 goto invalid;
2955                         goto queue;
2956                 }
2957                 default:
2958                         break;
2959                 }
2960                 break;
2961         case WLAN_CATEGORY_BACK:
2962                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2963                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2964                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2965                     sdata->vif.type != NL80211_IFTYPE_AP &&
2966                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2967                         break;
2968
2969                 /* verify action_code is present */
2970                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2971                         break;
2972
2973                 switch (mgmt->u.action.u.addba_req.action_code) {
2974                 case WLAN_ACTION_ADDBA_REQ:
2975                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2976                                    sizeof(mgmt->u.action.u.addba_req)))
2977                                 goto invalid;
2978                         break;
2979                 case WLAN_ACTION_ADDBA_RESP:
2980                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2981                                    sizeof(mgmt->u.action.u.addba_resp)))
2982                                 goto invalid;
2983                         break;
2984                 case WLAN_ACTION_DELBA:
2985                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2986                                    sizeof(mgmt->u.action.u.delba)))
2987                                 goto invalid;
2988                         break;
2989                 default:
2990                         goto invalid;
2991                 }
2992
2993                 goto queue;
2994         case WLAN_CATEGORY_SPECTRUM_MGMT:
2995                 /* verify action_code is present */
2996                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2997                         break;
2998
2999                 switch (mgmt->u.action.u.measurement.action_code) {
3000                 case WLAN_ACTION_SPCT_MSR_REQ:
3001                         if (status->band != NL80211_BAND_5GHZ)
3002                                 break;
3003
3004                         if (len < (IEEE80211_MIN_ACTION_SIZE +
3005                                    sizeof(mgmt->u.action.u.measurement)))
3006                                 break;
3007
3008                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
3009                                 break;
3010
3011                         ieee80211_process_measurement_req(sdata, mgmt, len);
3012                         goto handled;
3013                 case WLAN_ACTION_SPCT_CHL_SWITCH: {
3014                         u8 *bssid;
3015                         if (len < (IEEE80211_MIN_ACTION_SIZE +
3016                                    sizeof(mgmt->u.action.u.chan_switch)))
3017                                 break;
3018
3019                         if (sdata->vif.type != NL80211_IFTYPE_STATION &&
3020                             sdata->vif.type != NL80211_IFTYPE_ADHOC &&
3021                             sdata->vif.type != NL80211_IFTYPE_MESH_POINT)
3022                                 break;
3023
3024                         if (sdata->vif.type == NL80211_IFTYPE_STATION)
3025                                 bssid = sdata->u.mgd.bssid;
3026                         else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
3027                                 bssid = sdata->u.ibss.bssid;
3028                         else if (sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
3029                                 bssid = mgmt->sa;
3030                         else
3031                                 break;
3032
3033                         if (!ether_addr_equal(mgmt->bssid, bssid))
3034                                 break;
3035
3036                         goto queue;
3037                         }
3038                 }
3039                 break;
3040         case WLAN_CATEGORY_SA_QUERY:
3041                 if (len < (IEEE80211_MIN_ACTION_SIZE +
3042                            sizeof(mgmt->u.action.u.sa_query)))
3043                         break;
3044
3045                 switch (mgmt->u.action.u.sa_query.action) {
3046                 case WLAN_ACTION_SA_QUERY_REQUEST:
3047                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
3048                                 break;
3049                         ieee80211_process_sa_query_req(sdata, mgmt, len);
3050                         goto handled;
3051                 }
3052                 break;
3053         case WLAN_CATEGORY_SELF_PROTECTED:
3054                 if (len < (IEEE80211_MIN_ACTION_SIZE +
3055                            sizeof(mgmt->u.action.u.self_prot.action_code)))
3056                         break;
3057
3058                 switch (mgmt->u.action.u.self_prot.action_code) {
3059                 case WLAN_SP_MESH_PEERING_OPEN:
3060                 case WLAN_SP_MESH_PEERING_CLOSE:
3061                 case WLAN_SP_MESH_PEERING_CONFIRM:
3062                         if (!ieee80211_vif_is_mesh(&sdata->vif))
3063                                 goto invalid;
3064                         if (sdata->u.mesh.user_mpm)
3065                                 /* userspace handles this frame */
3066                                 break;
3067                         goto queue;
3068                 case WLAN_SP_MGK_INFORM:
3069                 case WLAN_SP_MGK_ACK:
3070                         if (!ieee80211_vif_is_mesh(&sdata->vif))
3071                                 goto invalid;
3072                         break;
3073                 }
3074                 break;
3075         case WLAN_CATEGORY_MESH_ACTION:
3076                 if (len < (IEEE80211_MIN_ACTION_SIZE +
3077                            sizeof(mgmt->u.action.u.mesh_action.action_code)))
3078                         break;
3079
3080                 if (!ieee80211_vif_is_mesh(&sdata->vif))
3081                         break;
3082                 if (mesh_action_is_path_sel(mgmt) &&
3083                     !mesh_path_sel_is_hwmp(sdata))
3084                         break;
3085                 goto queue;
3086         }
3087
3088         return RX_CONTINUE;
3089
3090  invalid:
3091         status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
3092         /* will return in the next handlers */
3093         return RX_CONTINUE;
3094
3095  handled:
3096         if (rx->sta)
3097                 rx->sta->rx_stats.packets++;
3098         dev_kfree_skb(rx->skb);
3099         return RX_QUEUED;
3100
3101  queue:
3102         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
3103         skb_queue_tail(&sdata->skb_queue, rx->skb);
3104         ieee80211_queue_work(&local->hw, &sdata->work);
3105         if (rx->sta)
3106                 rx->sta->rx_stats.packets++;
3107         return RX_QUEUED;
3108 }
3109
3110 static ieee80211_rx_result debug_noinline
3111 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
3112 {
3113         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
3114         int sig = 0;
3115
3116         /* skip known-bad action frames and return them in the next handler */
3117         if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
3118                 return RX_CONTINUE;
3119
3120         /*
3121          * Getting here means the kernel doesn't know how to handle
3122          * it, but maybe userspace does ... include returned frames
3123          * so userspace can register for those to know whether ones
3124          * it transmitted were processed or returned.
3125          */
3126
3127         if (ieee80211_hw_check(&rx->local->hw, SIGNAL_DBM))
3128                 sig = status->signal;
3129
3130         if (cfg80211_rx_mgmt(&rx->sdata->wdev, status->freq, sig,
3131                              rx->skb->data, rx->skb->len, 0)) {
3132                 if (rx->sta)
3133                         rx->sta->rx_stats.packets++;
3134                 dev_kfree_skb(rx->skb);
3135                 return RX_QUEUED;
3136         }
3137
3138         return RX_CONTINUE;
3139 }
3140
3141 static ieee80211_rx_result debug_noinline
3142 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
3143 {
3144         struct ieee80211_local *local = rx->local;
3145         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
3146         struct sk_buff *nskb;
3147         struct ieee80211_sub_if_data *sdata = rx->sdata;
3148         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
3149
3150         if (!ieee80211_is_action(mgmt->frame_control))
3151                 return RX_CONTINUE;
3152
3153         /*
3154          * For AP mode, hostapd is responsible for handling any action
3155          * frames that we didn't handle, including returning unknown
3156          * ones. For all other modes we will return them to the sender,
3157          * setting the 0x80 bit in the action category, as required by
3158          * 802.11-2012 9.24.4.
3159          * Newer versions of hostapd shall also use the management frame
3160          * registration mechanisms, but older ones still use cooked
3161          * monitor interfaces so push all frames there.
3162          */
3163         if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
3164             (sdata->vif.type == NL80211_IFTYPE_AP ||
3165              sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
3166                 return RX_DROP_MONITOR;
3167
3168         if (is_multicast_ether_addr(mgmt->da))
3169                 return RX_DROP_MONITOR;
3170
3171         /* do not return rejected action frames */
3172         if (mgmt->u.action.category & 0x80)
3173                 return RX_DROP_UNUSABLE;
3174
3175         nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
3176                                GFP_ATOMIC);
3177         if (nskb) {
3178                 struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
3179
3180                 nmgmt->u.action.category |= 0x80;
3181                 memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
3182                 memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
3183
3184                 memset(nskb->cb, 0, sizeof(nskb->cb));
3185
3186                 if (rx->sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE) {
3187                         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(nskb);
3188
3189                         info->flags = IEEE80211_TX_CTL_TX_OFFCHAN |
3190                                       IEEE80211_TX_INTFL_OFFCHAN_TX_OK |
3191                                       IEEE80211_TX_CTL_NO_CCK_RATE;
3192                         if (ieee80211_hw_check(&local->hw, QUEUE_CONTROL))
3193                                 info->hw_queue =
3194                                         local->hw.offchannel_tx_hw_queue;
3195                 }
3196
3197                 __ieee80211_tx_skb_tid_band(rx->sdata, nskb, 7,
3198                                             status->band);
3199         }
3200         dev_kfree_skb(rx->skb);
3201         return RX_QUEUED;
3202 }
3203
3204 static ieee80211_rx_result debug_noinline
3205 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
3206 {
3207         struct ieee80211_sub_if_data *sdata = rx->sdata;
3208         struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
3209         __le16 stype;
3210
3211         stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
3212
3213         if (!ieee80211_vif_is_mesh(&sdata->vif) &&
3214             sdata->vif.type != NL80211_IFTYPE_ADHOC &&
3215             sdata->vif.type != NL80211_IFTYPE_OCB &&
3216             sdata->vif.type != NL80211_IFTYPE_STATION)
3217                 return RX_DROP_MONITOR;
3218
3219         switch (stype) {
3220         case cpu_to_le16(IEEE80211_STYPE_AUTH):
3221         case cpu_to_le16(IEEE80211_STYPE_BEACON):
3222         case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
3223                 /* process for all: mesh, mlme, ibss */
3224                 break;
3225         case cpu_to_le16(IEEE80211_STYPE_ASSOC_RESP):
3226         case cpu_to_le16(IEEE80211_STYPE_REASSOC_RESP):
3227         case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
3228         case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
3229                 if (is_multicast_ether_addr(mgmt->da) &&
3230                     !is_broadcast_ether_addr(mgmt->da))
3231                         return RX_DROP_MONITOR;
3232
3233                 /* process only for station */
3234                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
3235                         return RX_DROP_MONITOR;
3236                 break;
3237         case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
3238                 /* process only for ibss and mesh */
3239                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC &&
3240                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT)
3241                         return RX_DROP_MONITOR;
3242                 break;
3243         default:
3244                 return RX_DROP_MONITOR;
3245         }
3246
3247         /* queue up frame and kick off work to process it */
3248         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
3249         skb_queue_tail(&sdata->skb_queue, rx->skb);
3250         ieee80211_queue_work(&rx->local->hw, &sdata->work);
3251         if (rx->sta)
3252                 rx->sta->rx_stats.packets++;
3253
3254         return RX_QUEUED;
3255 }
3256
3257 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
3258                                         struct ieee80211_rate *rate)
3259 {
3260         struct ieee80211_sub_if_data *sdata;
3261         struct ieee80211_local *local = rx->local;
3262         struct sk_buff *skb = rx->skb, *skb2;
3263         struct net_device *prev_dev = NULL;
3264         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3265         int needed_headroom;
3266
3267         /*
3268          * If cooked monitor has been processed already, then
3269          * don't do it again. If not, set the flag.
3270          */
3271         if (rx->flags & IEEE80211_RX_CMNTR)
3272                 goto out_free_skb;
3273         rx->flags |= IEEE80211_RX_CMNTR;
3274
3275         /* If there are no cooked monitor interfaces, just free the SKB */
3276         if (!local->cooked_mntrs)
3277                 goto out_free_skb;
3278
3279         /* vendor data is long removed here */
3280         status->flag &= ~RX_FLAG_RADIOTAP_VENDOR_DATA;
3281         /* room for the radiotap header based on driver features */
3282         needed_headroom = ieee80211_rx_radiotap_hdrlen(local, status, skb);
3283
3284         if (skb_headroom(skb) < needed_headroom &&
3285             pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC))
3286                 goto out_free_skb;
3287
3288         /* prepend radiotap information */
3289         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
3290                                          false);
3291
3292         skb_reset_mac_header(skb);
3293         skb->ip_summed = CHECKSUM_UNNECESSARY;
3294         skb->pkt_type = PACKET_OTHERHOST;
3295         skb->protocol = htons(ETH_P_802_2);
3296
3297         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
3298                 if (!ieee80211_sdata_running(sdata))
3299                         continue;
3300
3301                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
3302                     !(sdata->u.mntr.flags & MONITOR_FLAG_COOK_FRAMES))
3303                         continue;
3304
3305                 if (prev_dev) {
3306                         skb2 = skb_clone(skb, GFP_ATOMIC);
3307                         if (skb2) {
3308                                 skb2->dev = prev_dev;
3309                                 netif_receive_skb(skb2);
3310                         }
3311                 }
3312
3313                 prev_dev = sdata->dev;
3314                 ieee80211_rx_stats(sdata->dev, skb->len);
3315         }
3316
3317         if (prev_dev) {
3318                 skb->dev = prev_dev;
3319                 netif_receive_skb(skb);
3320                 return;
3321         }
3322
3323  out_free_skb:
3324         dev_kfree_skb(skb);
3325 }
3326
3327 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
3328                                          ieee80211_rx_result res)
3329 {
3330         switch (res) {
3331         case RX_DROP_MONITOR:
3332                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
3333                 if (rx->sta)
3334                         rx->sta->rx_stats.dropped++;
3335                 /* fall through */
3336         case RX_CONTINUE: {
3337                 struct ieee80211_rate *rate = NULL;
3338                 struct ieee80211_supported_band *sband;
3339                 struct ieee80211_rx_status *status;
3340
3341                 status = IEEE80211_SKB_RXCB((rx->skb));
3342
3343                 sband = rx->local->hw.wiphy->bands[status->band];
3344                 if (!(status->encoding == RX_ENC_HT) &&
3345                     !(status->encoding == RX_ENC_VHT))
3346                         rate = &sband->bitrates[status->rate_idx];
3347
3348                 ieee80211_rx_cooked_monitor(rx, rate);
3349                 break;
3350                 }
3351         case RX_DROP_UNUSABLE:
3352                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
3353                 if (rx->sta)
3354                         rx->sta->rx_stats.dropped++;
3355                 dev_kfree_skb(rx->skb);
3356                 break;
3357         case RX_QUEUED:
3358                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
3359                 break;
3360         }
3361 }
3362
3363 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
3364                                   struct sk_buff_head *frames)
3365 {
3366         ieee80211_rx_result res = RX_DROP_MONITOR;
3367         struct sk_buff *skb;
3368
3369 #define CALL_RXH(rxh)                   \
3370         do {                            \
3371                 res = rxh(rx);          \
3372                 if (res != RX_CONTINUE) \
3373                         goto rxh_next;  \
3374         } while (0)
3375
3376         /* Lock here to avoid hitting all of the data used in the RX
3377          * path (e.g. key data, station data, ...) concurrently when
3378          * a frame is released from the reorder buffer due to timeout
3379          * from the timer, potentially concurrently with RX from the
3380          * driver.
3381          */
3382         spin_lock_bh(&rx->local->rx_path_lock);
3383
3384         while ((skb = __skb_dequeue(frames))) {
3385                 /*
3386                  * all the other fields are valid across frames
3387                  * that belong to an aMPDU since they are on the
3388                  * same TID from the same station
3389                  */
3390                 rx->skb = skb;
3391
3392                 CALL_RXH(ieee80211_rx_h_check_more_data);
3393                 CALL_RXH(ieee80211_rx_h_uapsd_and_pspoll);
3394                 CALL_RXH(ieee80211_rx_h_sta_process);
3395                 CALL_RXH(ieee80211_rx_h_decrypt);
3396                 CALL_RXH(ieee80211_rx_h_defragment);
3397                 CALL_RXH(ieee80211_rx_h_michael_mic_verify);
3398                 /* must be after MMIC verify so header is counted in MPDU mic */
3399 #ifdef CONFIG_MAC80211_MESH
3400                 if (ieee80211_vif_is_mesh(&rx->sdata->vif))
3401                         CALL_RXH(ieee80211_rx_h_mesh_fwding);
3402 #endif
3403                 CALL_RXH(ieee80211_rx_h_amsdu);
3404                 CALL_RXH(ieee80211_rx_h_data);
3405
3406                 /* special treatment -- needs the queue */
3407                 res = ieee80211_rx_h_ctrl(rx, frames);
3408                 if (res != RX_CONTINUE)
3409                         goto rxh_next;
3410
3411                 CALL_RXH(ieee80211_rx_h_mgmt_check);
3412                 CALL_RXH(ieee80211_rx_h_action);
3413                 CALL_RXH(ieee80211_rx_h_userspace_mgmt);
3414                 CALL_RXH(ieee80211_rx_h_action_return);
3415                 CALL_RXH(ieee80211_rx_h_mgmt);
3416
3417  rxh_next:
3418                 ieee80211_rx_handlers_result(rx, res);
3419
3420 #undef CALL_RXH
3421         }
3422
3423         spin_unlock_bh(&rx->local->rx_path_lock);
3424 }
3425
3426 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
3427 {
3428         struct sk_buff_head reorder_release;
3429         ieee80211_rx_result res = RX_DROP_MONITOR;
3430
3431         __skb_queue_head_init(&reorder_release);
3432
3433 #define CALL_RXH(rxh)                   \
3434         do {                            \
3435                 res = rxh(rx);          \
3436                 if (res != RX_CONTINUE) \
3437                         goto rxh_next;  \
3438         } while (0)
3439
3440         CALL_RXH(ieee80211_rx_h_check_dup);
3441         CALL_RXH(ieee80211_rx_h_check);
3442
3443         ieee80211_rx_reorder_ampdu(rx, &reorder_release);
3444
3445         ieee80211_rx_handlers(rx, &reorder_release);
3446         return;
3447
3448  rxh_next:
3449         ieee80211_rx_handlers_result(rx, res);
3450
3451 #undef CALL_RXH
3452 }
3453
3454 /*
3455  * This function makes calls into the RX path, therefore
3456  * it has to be invoked under RCU read lock.
3457  */
3458 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
3459 {
3460         struct sk_buff_head frames;
3461         struct ieee80211_rx_data rx = {
3462                 .sta = sta,
3463                 .sdata = sta->sdata,
3464                 .local = sta->local,
3465                 /* This is OK -- must be QoS data frame */
3466                 .security_idx = tid,
3467                 .seqno_idx = tid,
3468                 .napi = NULL, /* must be NULL to not have races */
3469         };
3470         struct tid_ampdu_rx *tid_agg_rx;
3471
3472         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
3473         if (!tid_agg_rx)
3474                 return;
3475
3476         __skb_queue_head_init(&frames);
3477
3478         spin_lock(&tid_agg_rx->reorder_lock);
3479         ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx, &frames);
3480         spin_unlock(&tid_agg_rx->reorder_lock);
3481
3482         if (!skb_queue_empty(&frames)) {
3483                 struct ieee80211_event event = {
3484                         .type = BA_FRAME_TIMEOUT,
3485                         .u.ba.tid = tid,
3486                         .u.ba.sta = &sta->sta,
3487                 };
3488                 drv_event_callback(rx.local, rx.sdata, &event);
3489         }
3490
3491         ieee80211_rx_handlers(&rx, &frames);
3492 }
3493
3494 void ieee80211_mark_rx_ba_filtered_frames(struct ieee80211_sta *pubsta, u8 tid,
3495                                           u16 ssn, u64 filtered,
3496                                           u16 received_mpdus)
3497 {
3498         struct sta_info *sta;
3499         struct tid_ampdu_rx *tid_agg_rx;
3500         struct sk_buff_head frames;
3501         struct ieee80211_rx_data rx = {
3502                 /* This is OK -- must be QoS data frame */
3503                 .security_idx = tid,
3504                 .seqno_idx = tid,
3505         };
3506         int i, diff;
3507
3508         if (WARN_ON(!pubsta || tid >= IEEE80211_NUM_TIDS))
3509                 return;
3510
3511         __skb_queue_head_init(&frames);
3512
3513         sta = container_of(pubsta, struct sta_info, sta);
3514
3515         rx.sta = sta;
3516         rx.sdata = sta->sdata;
3517         rx.local = sta->local;
3518
3519         rcu_read_lock();
3520         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
3521         if (!tid_agg_rx)
3522                 goto out;
3523
3524         spin_lock_bh(&tid_agg_rx->reorder_lock);
3525
3526         if (received_mpdus >= IEEE80211_SN_MODULO >> 1) {
3527                 int release;
3528
3529                 /* release all frames in the reorder buffer */
3530                 release = (tid_agg_rx->head_seq_num + tid_agg_rx->buf_size) %
3531                            IEEE80211_SN_MODULO;
3532                 ieee80211_release_reorder_frames(sta->sdata, tid_agg_rx,
3533                                                  release, &frames);
3534                 /* update ssn to match received ssn */
3535                 tid_agg_rx->head_seq_num = ssn;
3536         } else {
3537                 ieee80211_release_reorder_frames(sta->sdata, tid_agg_rx, ssn,
3538                                                  &frames);
3539         }
3540
3541         /* handle the case that received ssn is behind the mac ssn.
3542          * it can be tid_agg_rx->buf_size behind and still be valid */
3543         diff = (tid_agg_rx->head_seq_num - ssn) & IEEE80211_SN_MASK;
3544         if (diff >= tid_agg_rx->buf_size) {
3545                 tid_agg_rx->reorder_buf_filtered = 0;
3546                 goto release;
3547         }
3548         filtered = filtered >> diff;
3549         ssn += diff;
3550
3551         /* update bitmap */
3552         for (i = 0; i < tid_agg_rx->buf_size; i++) {
3553                 int index = (ssn + i) % tid_agg_rx->buf_size;
3554
3555                 tid_agg_rx->reorder_buf_filtered &= ~BIT_ULL(index);
3556                 if (filtered & BIT_ULL(i))
3557                         tid_agg_rx->reorder_buf_filtered |= BIT_ULL(index);
3558         }
3559
3560         /* now process also frames that the filter marking released */
3561         ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx, &frames);
3562
3563 release:
3564         spin_unlock_bh(&tid_agg_rx->reorder_lock);
3565
3566         ieee80211_rx_handlers(&rx, &frames);
3567
3568  out:
3569         rcu_read_unlock();
3570 }
3571 EXPORT_SYMBOL(ieee80211_mark_rx_ba_filtered_frames);
3572
3573 /* main receive path */
3574
3575 static bool ieee80211_accept_frame(struct ieee80211_rx_data *rx)
3576 {
3577         struct ieee80211_sub_if_data *sdata = rx->sdata;
3578         struct sk_buff *skb = rx->skb;
3579         struct ieee80211_hdr *hdr = (void *)skb->data;
3580         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3581         u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
3582         bool multicast = is_multicast_ether_addr(hdr->addr1);
3583
3584         switch (sdata->vif.type) {
3585         case NL80211_IFTYPE_STATION:
3586                 if (!bssid && !sdata->u.mgd.use_4addr)
3587                         return false;
3588                 if (multicast)
3589                         return true;
3590                 return ether_addr_equal(sdata->vif.addr, hdr->addr1);
3591         case NL80211_IFTYPE_ADHOC:
3592                 if (!bssid)
3593                         return false;
3594                 if (ether_addr_equal(sdata->vif.addr, hdr->addr2) ||
3595                     ether_addr_equal(sdata->u.ibss.bssid, hdr->addr2))
3596                         return false;
3597                 if (ieee80211_is_beacon(hdr->frame_control))
3598                         return true;
3599                 if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid))
3600                         return false;
3601                 if (!multicast &&
3602                     !ether_addr_equal(sdata->vif.addr, hdr->addr1))
3603                         return false;
3604                 if (!rx->sta) {
3605                         int rate_idx;
3606                         if (status->encoding != RX_ENC_LEGACY)
3607                                 rate_idx = 0; /* TODO: HT/VHT rates */
3608                         else
3609                                 rate_idx = status->rate_idx;
3610                         ieee80211_ibss_rx_no_sta(sdata, bssid, hdr->addr2,
3611                                                  BIT(rate_idx));
3612                 }
3613                 return true;
3614         case NL80211_IFTYPE_OCB:
3615                 if (!bssid)
3616                         return false;
3617                 if (!ieee80211_is_data_present(hdr->frame_control))
3618                         return false;
3619                 if (!is_broadcast_ether_addr(bssid))
3620                         return false;
3621                 if (!multicast &&
3622                     !ether_addr_equal(sdata->dev->dev_addr, hdr->addr1))
3623                         return false;
3624                 if (!rx->sta) {
3625                         int rate_idx;
3626                         if (status->encoding != RX_ENC_LEGACY)
3627                                 rate_idx = 0; /* TODO: HT rates */
3628                         else
3629                                 rate_idx = status->rate_idx;
3630                         ieee80211_ocb_rx_no_sta(sdata, bssid, hdr->addr2,
3631                                                 BIT(rate_idx));
3632                 }
3633                 return true;
3634         case NL80211_IFTYPE_MESH_POINT:
3635                 if (multicast)
3636                         return true;
3637                 return ether_addr_equal(sdata->vif.addr, hdr->addr1);
3638         case NL80211_IFTYPE_AP_VLAN:
3639         case NL80211_IFTYPE_AP:
3640                 if (!bssid)
3641                         return ether_addr_equal(sdata->vif.addr, hdr->addr1);
3642
3643                 if (!ieee80211_bssid_match(bssid, sdata->vif.addr)) {
3644                         /*
3645                          * Accept public action frames even when the
3646                          * BSSID doesn't match, this is used for P2P
3647                          * and location updates. Note that mac80211
3648                          * itself never looks at these frames.
3649                          */
3650                         if (!multicast &&
3651                             !ether_addr_equal(sdata->vif.addr, hdr->addr1))
3652                                 return false;
3653                         if (ieee80211_is_public_action(hdr, skb->len))
3654                                 return true;
3655                         return ieee80211_is_beacon(hdr->frame_control);
3656                 }
3657
3658                 if (!ieee80211_has_tods(hdr->frame_control)) {
3659                         /* ignore data frames to TDLS-peers */
3660                         if (ieee80211_is_data(hdr->frame_control))
3661                                 return false;
3662                         /* ignore action frames to TDLS-peers */
3663                         if (ieee80211_is_action(hdr->frame_control) &&
3664                             !is_broadcast_ether_addr(bssid) &&
3665                             !ether_addr_equal(bssid, hdr->addr1))
3666                                 return false;
3667                 }
3668
3669                 /*
3670                  * 802.11-2016 Table 9-26 says that for data frames, A1 must be
3671                  * the BSSID - we've checked that already but may have accepted
3672                  * the wildcard (ff:ff:ff:ff:ff:ff).
3673                  *
3674                  * It also says:
3675                  *      The BSSID of the Data frame is determined as follows:
3676                  *      a) If the STA is contained within an AP or is associated
3677                  *         with an AP, the BSSID is the address currently in use
3678                  *         by the STA contained in the AP.
3679                  *
3680                  * So we should not accept data frames with an address that's
3681                  * multicast.
3682                  *
3683                  * Accepting it also opens a security problem because stations
3684                  * could encrypt it with the GTK and inject traffic that way.
3685                  */
3686                 if (ieee80211_is_data(hdr->frame_control) && multicast)
3687                         return false;
3688
3689                 return true;
3690         case NL80211_IFTYPE_WDS:
3691                 if (bssid || !ieee80211_is_data(hdr->frame_control))
3692                         return false;
3693                 return ether_addr_equal(sdata->u.wds.remote_addr, hdr->addr2);
3694         case NL80211_IFTYPE_P2P_DEVICE:
3695                 return ieee80211_is_public_action(hdr, skb->len) ||
3696                        ieee80211_is_probe_req(hdr->frame_control) ||
3697                        ieee80211_is_probe_resp(hdr->frame_control) ||
3698                        ieee80211_is_beacon(hdr->frame_control);
3699         case NL80211_IFTYPE_NAN:
3700                 /* Currently no frames on NAN interface are allowed */
3701                 return false;
3702         default:
3703                 break;
3704         }
3705
3706         WARN_ON_ONCE(1);
3707         return false;
3708 }
3709
3710 void ieee80211_check_fast_rx(struct sta_info *sta)
3711 {
3712         struct ieee80211_sub_if_data *sdata = sta->sdata;
3713         struct ieee80211_local *local = sdata->local;
3714         struct ieee80211_key *key;
3715         struct ieee80211_fast_rx fastrx = {
3716                 .dev = sdata->dev,
3717                 .vif_type = sdata->vif.type,
3718                 .control_port_protocol = sdata->control_port_protocol,
3719         }, *old, *new = NULL;
3720         bool assign = false;
3721
3722         /* use sparse to check that we don't return without updating */
3723         __acquire(check_fast_rx);
3724
3725         BUILD_BUG_ON(sizeof(fastrx.rfc1042_hdr) != sizeof(rfc1042_header));
3726         BUILD_BUG_ON(sizeof(fastrx.rfc1042_hdr) != ETH_ALEN);
3727         ether_addr_copy(fastrx.rfc1042_hdr, rfc1042_header);
3728         ether_addr_copy(fastrx.vif_addr, sdata->vif.addr);
3729
3730         fastrx.uses_rss = ieee80211_hw_check(&local->hw, USES_RSS);
3731
3732         /* fast-rx doesn't do reordering */
3733         if (ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION) &&
3734             !ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER))
3735                 goto clear;
3736
3737         switch (sdata->vif.type) {
3738         case NL80211_IFTYPE_STATION:
3739                 /* 4-addr is harder to deal with, later maybe */
3740                 if (sdata->u.mgd.use_4addr)
3741                         goto clear;
3742                 /* software powersave is a huge mess, avoid all of it */
3743                 if (ieee80211_hw_check(&local->hw, PS_NULLFUNC_STACK))
3744                         goto clear;
3745                 if (ieee80211_hw_check(&local->hw, SUPPORTS_PS) &&
3746                     !ieee80211_hw_check(&local->hw, SUPPORTS_DYNAMIC_PS))
3747                         goto clear;
3748                 if (sta->sta.tdls) {
3749                         fastrx.da_offs = offsetof(struct ieee80211_hdr, addr1);
3750                         fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr2);
3751                         fastrx.expected_ds_bits = 0;
3752                 } else {
3753                         fastrx.sta_notify = sdata->u.mgd.probe_send_count > 0;
3754                         fastrx.da_offs = offsetof(struct ieee80211_hdr, addr1);
3755                         fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr3);
3756                         fastrx.expected_ds_bits =
3757                                 cpu_to_le16(IEEE80211_FCTL_FROMDS);
3758                 }
3759                 break;
3760         case NL80211_IFTYPE_AP_VLAN:
3761         case NL80211_IFTYPE_AP:
3762                 /* parallel-rx requires this, at least with calls to
3763                  * ieee80211_sta_ps_transition()
3764                  */
3765                 if (!ieee80211_hw_check(&local->hw, AP_LINK_PS))
3766                         goto clear;
3767                 fastrx.da_offs = offsetof(struct ieee80211_hdr, addr3);
3768                 fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr2);
3769                 fastrx.expected_ds_bits = cpu_to_le16(IEEE80211_FCTL_TODS);
3770
3771                 fastrx.internal_forward =
3772                         !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
3773                         (sdata->vif.type != NL80211_IFTYPE_AP_VLAN ||
3774                          !sdata->u.vlan.sta);
3775                 break;
3776         default:
3777                 goto clear;
3778         }
3779
3780         if (!test_sta_flag(sta, WLAN_STA_AUTHORIZED))
3781                 goto clear;
3782
3783         rcu_read_lock();
3784         key = rcu_dereference(sta->ptk[sta->ptk_idx]);
3785         if (key) {
3786                 switch (key->conf.cipher) {
3787                 case WLAN_CIPHER_SUITE_TKIP:
3788                         /* we don't want to deal with MMIC in fast-rx */
3789                         goto clear_rcu;
3790                 case WLAN_CIPHER_SUITE_CCMP:
3791                 case WLAN_CIPHER_SUITE_CCMP_256:
3792                 case WLAN_CIPHER_SUITE_GCMP:
3793                 case WLAN_CIPHER_SUITE_GCMP_256:
3794                         break;
3795                 default:
3796                         /* we also don't want to deal with WEP or cipher scheme
3797                          * since those require looking up the key idx in the
3798                          * frame, rather than assuming the PTK is used
3799                          * (we need to revisit this once we implement the real
3800                          * PTK index, which is now valid in the spec, but we
3801                          * haven't implemented that part yet)
3802                          */
3803                         goto clear_rcu;
3804                 }
3805
3806                 fastrx.key = true;
3807                 fastrx.icv_len = key->conf.icv_len;
3808         }
3809
3810         assign = true;
3811  clear_rcu:
3812         rcu_read_unlock();
3813  clear:
3814         __release(check_fast_rx);
3815
3816         if (assign)
3817                 new = kmemdup(&fastrx, sizeof(fastrx), GFP_KERNEL);
3818
3819         spin_lock_bh(&sta->lock);
3820         old = rcu_dereference_protected(sta->fast_rx, true);
3821         rcu_assign_pointer(sta->fast_rx, new);
3822         spin_unlock_bh(&sta->lock);
3823
3824         if (old)
3825                 kfree_rcu(old, rcu_head);
3826 }
3827
3828 void ieee80211_clear_fast_rx(struct sta_info *sta)
3829 {
3830         struct ieee80211_fast_rx *old;
3831
3832         spin_lock_bh(&sta->lock);
3833         old = rcu_dereference_protected(sta->fast_rx, true);
3834         RCU_INIT_POINTER(sta->fast_rx, NULL);
3835         spin_unlock_bh(&sta->lock);
3836
3837         if (old)
3838                 kfree_rcu(old, rcu_head);
3839 }
3840
3841 void __ieee80211_check_fast_rx_iface(struct ieee80211_sub_if_data *sdata)
3842 {
3843         struct ieee80211_local *local = sdata->local;
3844         struct sta_info *sta;
3845
3846         lockdep_assert_held(&local->sta_mtx);
3847
3848         list_for_each_entry_rcu(sta, &local->sta_list, list) {
3849                 if (sdata != sta->sdata &&
3850                     (!sta->sdata->bss || sta->sdata->bss != sdata->bss))
3851                         continue;
3852                 ieee80211_check_fast_rx(sta);
3853         }
3854 }
3855
3856 void ieee80211_check_fast_rx_iface(struct ieee80211_sub_if_data *sdata)
3857 {
3858         struct ieee80211_local *local = sdata->local;
3859
3860         mutex_lock(&local->sta_mtx);
3861         __ieee80211_check_fast_rx_iface(sdata);
3862         mutex_unlock(&local->sta_mtx);
3863 }
3864
3865 static bool ieee80211_invoke_fast_rx(struct ieee80211_rx_data *rx,
3866                                      struct ieee80211_fast_rx *fast_rx)
3867 {
3868         struct sk_buff *skb = rx->skb;
3869         struct ieee80211_hdr *hdr = (void *)skb->data;
3870         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3871         struct sta_info *sta = rx->sta;
3872         int orig_len = skb->len;
3873         int snap_offs = ieee80211_hdrlen(hdr->frame_control);
3874         struct {
3875                 u8 snap[sizeof(rfc1042_header)];
3876                 __be16 proto;
3877         } *payload __aligned(2);
3878         struct {
3879                 u8 da[ETH_ALEN];
3880                 u8 sa[ETH_ALEN];
3881         } addrs __aligned(2);
3882         struct ieee80211_sta_rx_stats *stats = &sta->rx_stats;
3883
3884         if (fast_rx->uses_rss)
3885                 stats = this_cpu_ptr(sta->pcpu_rx_stats);
3886
3887         /* for parallel-rx, we need to have DUP_VALIDATED, otherwise we write
3888          * to a common data structure; drivers can implement that per queue
3889          * but we don't have that information in mac80211
3890          */
3891         if (!(status->flag & RX_FLAG_DUP_VALIDATED))
3892                 return false;
3893
3894 #define FAST_RX_CRYPT_FLAGS     (RX_FLAG_PN_VALIDATED | RX_FLAG_DECRYPTED)
3895
3896         /* If using encryption, we also need to have:
3897          *  - PN_VALIDATED: similar, but the implementation is tricky
3898          *  - DECRYPTED: necessary for PN_VALIDATED
3899          */
3900         if (fast_rx->key &&
3901             (status->flag & FAST_RX_CRYPT_FLAGS) != FAST_RX_CRYPT_FLAGS)
3902                 return false;
3903
3904         /* we don't deal with A-MSDU deaggregation here */
3905         if (status->rx_flags & IEEE80211_RX_AMSDU)
3906                 return false;
3907
3908         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
3909                 return false;
3910
3911         if (unlikely(ieee80211_is_frag(hdr)))
3912                 return false;
3913
3914         /* Since our interface address cannot be multicast, this
3915          * implicitly also rejects multicast frames without the
3916          * explicit check.
3917          *
3918          * We shouldn't get any *data* frames not addressed to us
3919          * (AP mode will accept multicast *management* frames), but
3920          * punting here will make it go through the full checks in
3921          * ieee80211_accept_frame().
3922          */
3923         if (!ether_addr_equal(fast_rx->vif_addr, hdr->addr1))
3924                 return false;
3925
3926         if ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_FROMDS |
3927                                               IEEE80211_FCTL_TODS)) !=
3928             fast_rx->expected_ds_bits)
3929                 goto drop;
3930
3931         /* assign the key to drop unencrypted frames (later)
3932          * and strip the IV/MIC if necessary
3933          */
3934         if (fast_rx->key && !(status->flag & RX_FLAG_IV_STRIPPED)) {
3935                 /* GCMP header length is the same */
3936                 snap_offs += IEEE80211_CCMP_HDR_LEN;
3937         }
3938
3939         if (!pskb_may_pull(skb, snap_offs + sizeof(*payload)))
3940                 goto drop;
3941         payload = (void *)(skb->data + snap_offs);
3942
3943         if (!ether_addr_equal(payload->snap, fast_rx->rfc1042_hdr))
3944                 return false;
3945
3946         /* Don't handle these here since they require special code.
3947          * Accept AARP and IPX even though they should come with a
3948          * bridge-tunnel header - but if we get them this way then
3949          * there's little point in discarding them.
3950          */
3951         if (unlikely(payload->proto == cpu_to_be16(ETH_P_TDLS) ||
3952                      payload->proto == fast_rx->control_port_protocol))
3953                 return false;
3954
3955         /* after this point, don't punt to the slowpath! */
3956
3957         if (rx->key && !(status->flag & RX_FLAG_MIC_STRIPPED) &&
3958             pskb_trim(skb, skb->len - fast_rx->icv_len))
3959                 goto drop;
3960
3961         if (unlikely(fast_rx->sta_notify)) {
3962                 ieee80211_sta_rx_notify(rx->sdata, hdr);
3963                 fast_rx->sta_notify = false;
3964         }
3965
3966         /* statistics part of ieee80211_rx_h_sta_process() */
3967         stats->last_rx = jiffies;
3968         stats->last_rate = sta_stats_encode_rate(status);
3969
3970         stats->fragments++;
3971         stats->packets++;
3972
3973         if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
3974                 stats->last_signal = status->signal;
3975                 if (!fast_rx->uses_rss)
3976                         ewma_signal_add(&sta->rx_stats_avg.signal,
3977                                         -status->signal);
3978         }
3979
3980         if (status->chains) {
3981                 int i;
3982
3983                 stats->chains = status->chains;
3984                 for (i = 0; i < ARRAY_SIZE(status->chain_signal); i++) {
3985                         int signal = status->chain_signal[i];
3986
3987                         if (!(status->chains & BIT(i)))
3988                                 continue;
3989
3990                         stats->chain_signal_last[i] = signal;
3991                         if (!fast_rx->uses_rss)
3992                                 ewma_signal_add(&sta->rx_stats_avg.chain_signal[i],
3993                                                 -signal);
3994                 }
3995         }
3996         /* end of statistics */
3997
3998         if (rx->key && !ieee80211_has_protected(hdr->frame_control))
3999                 goto drop;
4000
4001         /* do the header conversion - first grab the addresses */
4002         ether_addr_copy(addrs.da, skb->data + fast_rx->da_offs);
4003         ether_addr_copy(addrs.sa, skb->data + fast_rx->sa_offs);
4004         /* remove the SNAP but leave the ethertype */
4005         skb_pull(skb, snap_offs + sizeof(rfc1042_header));
4006         /* push the addresses in front */
4007         memcpy(skb_push(skb, sizeof(addrs)), &addrs, sizeof(addrs));
4008
4009         skb->dev = fast_rx->dev;
4010
4011         ieee80211_rx_stats(fast_rx->dev, skb->len);
4012
4013         /* The seqno index has the same property as needed
4014          * for the rx_msdu field, i.e. it is IEEE80211_NUM_TIDS
4015          * for non-QoS-data frames. Here we know it's a data
4016          * frame, so count MSDUs.
4017          */
4018         u64_stats_update_begin(&stats->syncp);
4019         stats->msdu[rx->seqno_idx]++;
4020         stats->bytes += orig_len;
4021         u64_stats_update_end(&stats->syncp);
4022
4023         if (fast_rx->internal_forward) {
4024                 struct sk_buff *xmit_skb = NULL;
4025                 bool multicast = is_multicast_ether_addr(skb->data);
4026
4027                 if (multicast) {
4028                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
4029                 } else if (sta_info_get(rx->sdata, skb->data)) {
4030                         xmit_skb = skb;
4031                         skb = NULL;
4032                 }
4033
4034                 if (xmit_skb) {
4035                         /*
4036                          * Send to wireless media and increase priority by 256
4037                          * to keep the received priority instead of
4038                          * reclassifying the frame (see cfg80211_classify8021d).
4039                          */
4040                         xmit_skb->priority += 256;
4041                         xmit_skb->protocol = htons(ETH_P_802_3);
4042                         skb_reset_network_header(xmit_skb);
4043                         skb_reset_mac_header(xmit_skb);
4044                         dev_queue_xmit(xmit_skb);
4045                 }
4046
4047                 if (!skb)
4048                         return true;
4049         }
4050
4051         /* deliver to local stack */
4052         skb->protocol = eth_type_trans(skb, fast_rx->dev);
4053         memset(skb->cb, 0, sizeof(skb->cb));
4054         if (rx->napi)
4055                 napi_gro_receive(rx->napi, skb);
4056         else
4057                 netif_receive_skb(skb);
4058
4059         return true;
4060  drop:
4061         dev_kfree_skb(skb);
4062         stats->dropped++;
4063         return true;
4064 }
4065
4066 /*
4067  * This function returns whether or not the SKB
4068  * was destined for RX processing or not, which,
4069  * if consume is true, is equivalent to whether
4070  * or not the skb was consumed.
4071  */
4072 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
4073                                             struct sk_buff *skb, bool consume)
4074 {
4075         struct ieee80211_local *local = rx->local;
4076         struct ieee80211_sub_if_data *sdata = rx->sdata;
4077
4078         rx->skb = skb;
4079
4080         /* See if we can do fast-rx; if we have to copy we already lost,
4081          * so punt in that case. We should never have to deliver a data
4082          * frame to multiple interfaces anyway.
4083          *
4084          * We skip the ieee80211_accept_frame() call and do the necessary
4085          * checking inside ieee80211_invoke_fast_rx().
4086          */
4087         if (consume && rx->sta) {
4088                 struct ieee80211_fast_rx *fast_rx;
4089
4090                 fast_rx = rcu_dereference(rx->sta->fast_rx);
4091                 if (fast_rx && ieee80211_invoke_fast_rx(rx, fast_rx))
4092                         return true;
4093         }
4094
4095         if (!ieee80211_accept_frame(rx))
4096                 return false;
4097
4098         if (!consume) {
4099                 skb = skb_copy(skb, GFP_ATOMIC);
4100                 if (!skb) {
4101                         if (net_ratelimit())
4102                                 wiphy_debug(local->hw.wiphy,
4103                                         "failed to copy skb for %s\n",
4104                                         sdata->name);
4105                         return true;
4106                 }
4107
4108                 rx->skb = skb;
4109         }
4110
4111         ieee80211_invoke_rx_handlers(rx);
4112         return true;
4113 }
4114
4115 /*
4116  * This is the actual Rx frames handler. as it belongs to Rx path it must
4117  * be called with rcu_read_lock protection.
4118  */
4119 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
4120                                          struct ieee80211_sta *pubsta,
4121                                          struct sk_buff *skb,
4122                                          struct napi_struct *napi)
4123 {
4124         struct ieee80211_local *local = hw_to_local(hw);
4125         struct ieee80211_sub_if_data *sdata;
4126         struct ieee80211_hdr *hdr;
4127         __le16 fc;
4128         struct ieee80211_rx_data rx;
4129         struct ieee80211_sub_if_data *prev;
4130         struct rhlist_head *tmp;
4131         int err = 0;
4132
4133         fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
4134         memset(&rx, 0, sizeof(rx));
4135         rx.skb = skb;
4136         rx.local = local;
4137         rx.napi = napi;
4138
4139         if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
4140                 I802_DEBUG_INC(local->dot11ReceivedFragmentCount);
4141
4142         if (ieee80211_is_mgmt(fc)) {
4143                 /* drop frame if too short for header */
4144                 if (skb->len < ieee80211_hdrlen(fc))
4145                         err = -ENOBUFS;
4146                 else
4147                         err = skb_linearize(skb);
4148         } else {
4149                 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
4150         }
4151
4152         if (err) {
4153                 dev_kfree_skb(skb);
4154                 return;
4155         }
4156
4157         hdr = (struct ieee80211_hdr *)skb->data;
4158         ieee80211_parse_qos(&rx);
4159         ieee80211_verify_alignment(&rx);
4160
4161         if (unlikely(ieee80211_is_probe_resp(hdr->frame_control) ||
4162                      ieee80211_is_beacon(hdr->frame_control)))
4163                 ieee80211_scan_rx(local, skb);
4164
4165         if (ieee80211_is_data(fc)) {
4166                 struct sta_info *sta, *prev_sta;
4167
4168                 if (pubsta) {
4169                         rx.sta = container_of(pubsta, struct sta_info, sta);
4170                         rx.sdata = rx.sta->sdata;
4171                         if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
4172                                 return;
4173                         goto out;
4174                 }
4175
4176                 prev_sta = NULL;
4177
4178                 for_each_sta_info(local, hdr->addr2, sta, tmp) {
4179                         if (!prev_sta) {
4180                                 prev_sta = sta;
4181                                 continue;
4182                         }
4183
4184                         rx.sta = prev_sta;
4185                         rx.sdata = prev_sta->sdata;
4186                         ieee80211_prepare_and_rx_handle(&rx, skb, false);
4187
4188                         prev_sta = sta;
4189                 }
4190
4191                 if (prev_sta) {
4192                         rx.sta = prev_sta;
4193                         rx.sdata = prev_sta->sdata;
4194
4195                         if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
4196                                 return;
4197                         goto out;
4198                 }
4199         }
4200
4201         prev = NULL;
4202
4203         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
4204                 if (!ieee80211_sdata_running(sdata))
4205                         continue;
4206
4207                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
4208                     sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
4209                         continue;
4210
4211                 /*
4212                  * frame is destined for this interface, but if it's
4213                  * not also for the previous one we handle that after
4214                  * the loop to avoid copying the SKB once too much
4215                  */
4216
4217                 if (!prev) {
4218                         prev = sdata;
4219                         continue;
4220                 }
4221
4222                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
4223                 rx.sdata = prev;
4224                 ieee80211_prepare_and_rx_handle(&rx, skb, false);
4225
4226                 prev = sdata;
4227         }
4228
4229         if (prev) {
4230                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
4231                 rx.sdata = prev;
4232
4233                 if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
4234                         return;
4235         }
4236
4237  out:
4238         dev_kfree_skb(skb);
4239 }
4240
4241 /*
4242  * This is the receive path handler. It is called by a low level driver when an
4243  * 802.11 MPDU is received from the hardware.
4244  */
4245 void ieee80211_rx_napi(struct ieee80211_hw *hw, struct ieee80211_sta *pubsta,
4246                        struct sk_buff *skb, struct napi_struct *napi)
4247 {
4248         struct ieee80211_local *local = hw_to_local(hw);
4249         struct ieee80211_rate *rate = NULL;
4250         struct ieee80211_supported_band *sband;
4251         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
4252
4253         WARN_ON_ONCE(softirq_count() == 0);
4254
4255         if (WARN_ON(status->band >= NUM_NL80211_BANDS))
4256                 goto drop;
4257
4258         sband = local->hw.wiphy->bands[status->band];
4259         if (WARN_ON(!sband))
4260                 goto drop;
4261
4262         /*
4263          * If we're suspending, it is possible although not too likely
4264          * that we'd be receiving frames after having already partially
4265          * quiesced the stack. We can't process such frames then since
4266          * that might, for example, cause stations to be added or other
4267          * driver callbacks be invoked.
4268          */
4269         if (unlikely(local->quiescing || local->suspended))
4270                 goto drop;
4271
4272         /* We might be during a HW reconfig, prevent Rx for the same reason */
4273         if (unlikely(local->in_reconfig))
4274                 goto drop;
4275
4276         /*
4277          * The same happens when we're not even started,
4278          * but that's worth a warning.
4279          */
4280         if (WARN_ON(!local->started))
4281                 goto drop;
4282
4283         if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
4284                 /*
4285                  * Validate the rate, unless a PLCP error means that
4286                  * we probably can't have a valid rate here anyway.
4287                  */
4288
4289                 switch (status->encoding) {
4290                 case RX_ENC_HT:
4291                         /*
4292                          * rate_idx is MCS index, which can be [0-76]
4293                          * as documented on:
4294                          *
4295                          * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
4296                          *
4297                          * Anything else would be some sort of driver or
4298                          * hardware error. The driver should catch hardware
4299                          * errors.
4300                          */
4301                         if (WARN(status->rate_idx > 76,
4302                                  "Rate marked as an HT rate but passed "
4303                                  "status->rate_idx is not "
4304                                  "an MCS index [0-76]: %d (0x%02x)\n",
4305                                  status->rate_idx,
4306                                  status->rate_idx))
4307                                 goto drop;
4308                         break;
4309                 case RX_ENC_VHT:
4310                         if (WARN_ONCE(status->rate_idx > 9 ||
4311                                       !status->nss ||
4312                                       status->nss > 8,
4313                                       "Rate marked as a VHT rate but data is invalid: MCS: %d, NSS: %d\n",
4314                                       status->rate_idx, status->nss))
4315                                 goto drop;
4316                         break;
4317                 default:
4318                         WARN_ON_ONCE(1);
4319                         /* fall through */
4320                 case RX_ENC_LEGACY:
4321                         if (WARN_ON(status->rate_idx >= sband->n_bitrates))
4322                                 goto drop;
4323                         rate = &sband->bitrates[status->rate_idx];
4324                 }
4325         }
4326
4327         status->rx_flags = 0;
4328
4329         /*
4330          * key references and virtual interfaces are protected using RCU
4331          * and this requires that we are in a read-side RCU section during
4332          * receive processing
4333          */
4334         rcu_read_lock();
4335
4336         /*
4337          * Frames with failed FCS/PLCP checksum are not returned,
4338          * all other frames are returned without radiotap header
4339          * if it was previously present.
4340          * Also, frames with less than 16 bytes are dropped.
4341          */
4342         skb = ieee80211_rx_monitor(local, skb, rate);
4343         if (!skb) {
4344                 rcu_read_unlock();
4345                 return;
4346         }
4347
4348         ieee80211_tpt_led_trig_rx(local,
4349                         ((struct ieee80211_hdr *)skb->data)->frame_control,
4350                         skb->len);
4351
4352         __ieee80211_rx_handle_packet(hw, pubsta, skb, napi);
4353
4354         rcu_read_unlock();
4355
4356         return;
4357  drop:
4358         kfree_skb(skb);
4359 }
4360 EXPORT_SYMBOL(ieee80211_rx_napi);
4361
4362 /* This is a version of the rx handler that can be called from hard irq
4363  * context. Post the skb on the queue and schedule the tasklet */
4364 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
4365 {
4366         struct ieee80211_local *local = hw_to_local(hw);
4367
4368         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
4369
4370         skb->pkt_type = IEEE80211_RX_MSG;
4371         skb_queue_tail(&local->skb_queue, skb);
4372         tasklet_schedule(&local->tasklet);
4373 }
4374 EXPORT_SYMBOL(ieee80211_rx_irqsafe);