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_queue_tail(&sdata->skb_queue, skb);
 241         ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 242 }
 243
 244 /*
 245  * ieee80211_add_rx_radiotap_header - add radiotap header
 246  *
 247  * add a radiotap header containing all the fields which the hardware provided.
 248  */
 249 static void
 250 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
 251                                  struct sk_buff *skb,
 252                                  struct ieee80211_rate *rate,
 253                                  int rtap_len, bool has_fcs)
 254 {
 255         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 256         struct ieee80211_radiotap_header *rthdr;
 257         unsigned char *pos;
 258         __le32 *it_present;
 259         u32 it_present_val;
 260         u16 rx_flags = 0;
 261         u16 channel_flags = 0;
 262         int mpdulen, chain;
 263         unsigned long chains = status->chains;
 264         struct ieee80211_vendor_radiotap rtap = {};
 265
 266         if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) {
 267                 rtap = *(struct ieee80211_vendor_radiotap *)skb->data;
 268                 /* rtap.len and rtap.pad are undone immediately */
 269                 skb_pull(skb, sizeof(rtap) + rtap.len + rtap.pad);
 270         }
 271
 272         mpdulen = skb->len;
 273         if (!(has_fcs && ieee80211_hw_check(&local->hw, RX_INCLUDES_FCS)))
 274                 mpdulen += FCS_LEN;
 275
 276         rthdr = skb_push(skb, rtap_len);
 277         memset(rthdr, 0, rtap_len - rtap.len - rtap.pad);
 278         it_present = &rthdr->it_present;
 279
 280         /* radiotap header, set always present flags */
 281         rthdr->it_len = cpu_to_le16(rtap_len);
 282         it_present_val = BIT(IEEE80211_RADIOTAP_FLAGS) |
 283                          BIT(IEEE80211_RADIOTAP_CHANNEL) |
 284                          BIT(IEEE80211_RADIOTAP_RX_FLAGS);
 285
 286         if (!status->chains)
 287                 it_present_val |= BIT(IEEE80211_RADIOTAP_ANTENNA);
 288
 289         for_each_set_bit(chain, &chains, IEEE80211_MAX_CHAINS) {
 290                 it_present_val |=
 291                         BIT(IEEE80211_RADIOTAP_EXT) |
 292                         BIT(IEEE80211_RADIOTAP_RADIOTAP_NAMESPACE);
 293                 put_unaligned_le32(it_present_val, it_present);
 294                 it_present++;
 295                 it_present_val = BIT(IEEE80211_RADIOTAP_ANTENNA) |
 296                                  BIT(IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
 297         }
 298
 299         if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) {
 300                 it_present_val |= BIT(IEEE80211_RADIOTAP_VENDOR_NAMESPACE) |
 301                                   BIT(IEEE80211_RADIOTAP_EXT);
 302                 put_unaligned_le32(it_present_val, it_present);
 303                 it_present++;
 304                 it_present_val = rtap.present;
 305         }
 306
 307         put_unaligned_le32(it_present_val, it_present);
 308
 309         pos = (void *)(it_present + 1);
 310
 311         /* the order of the following fields is important */
 312
 313         /* IEEE80211_RADIOTAP_TSFT */
 314         if (ieee80211_have_rx_timestamp(status)) {
 315                 /* padding */
 316                 while ((pos - (u8 *)rthdr) & 7)
 317                         *pos++ = 0;
 318                 put_unaligned_le64(
 319                         ieee80211_calculate_rx_timestamp(local, status,
 320                                                          mpdulen, 0),
 321                         pos);
 322                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
 323                 pos += 8;
 324         }
 325
 326         /* IEEE80211_RADIOTAP_FLAGS */
 327         if (has_fcs && ieee80211_hw_check(&local->hw, RX_INCLUDES_FCS))
 328                 *pos |= IEEE80211_RADIOTAP_F_FCS;
 329         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 330                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
 331         if (status->enc_flags & RX_ENC_FLAG_SHORTPRE)
 332                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
 333         pos++;
 334
 335         /* IEEE80211_RADIOTAP_RATE */
 336         if (!rate || status->encoding != RX_ENC_LEGACY) {
 337                 /*
 338                  * Without rate information don't add it. If we have,
 339                  * MCS information is a separate field in radiotap,
 340                  * added below. The byte here is needed as padding
 341                  * for the channel though, so initialise it to 0.
 342                  */
 343                 *pos = 0;
 344         } else {
 345                 int shift = 0;
 346                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
 347                 if (status->bw == RATE_INFO_BW_10)
 348                         shift = 1;
 349                 else if (status->bw == RATE_INFO_BW_5)
 350                         shift = 2;
 351                 *pos = DIV_ROUND_UP(rate->bitrate, 5 * (1 << shift));
 352         }
 353         pos++;
 354
 355         /* IEEE80211_RADIOTAP_CHANNEL */
 356         put_unaligned_le16(status->freq, pos);
 357         pos += 2;
 358         if (status->bw == RATE_INFO_BW_10)
 359                 channel_flags |= IEEE80211_CHAN_HALF;
 360         else if (status->bw == RATE_INFO_BW_5)
 361                 channel_flags |= IEEE80211_CHAN_QUARTER;
 362
 363         if (status->band == NL80211_BAND_5GHZ)
 364                 channel_flags |= IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ;
 365         else if (status->encoding != RX_ENC_LEGACY)
 366                 channel_flags |= IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ;
 367         else if (rate && rate->flags & IEEE80211_RATE_ERP_G)
 368                 channel_flags |= IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ;
 369         else if (rate)
 370                 channel_flags |= IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ;
 371         else
 372                 channel_flags |= IEEE80211_CHAN_2GHZ;
 373         put_unaligned_le16(channel_flags, pos);
 374         pos += 2;
 375
 376         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
 377         if (ieee80211_hw_check(&local->hw, SIGNAL_DBM) &&
 378             !(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
 379                 *pos = status->signal;
 380                 rthdr->it_present |=
 381                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
 382                 pos++;
 383         }
 384
 385         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
 386
 387         if (!status->chains) {
 388                 /* IEEE80211_RADIOTAP_ANTENNA */
 389                 *pos = status->antenna;
 390                 pos++;
 391         }
 392
 393         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
 394
 395         /* IEEE80211_RADIOTAP_RX_FLAGS */
 396         /* ensure 2 byte alignment for the 2 byte field as required */
 397         if ((pos - (u8 *)rthdr) & 1)
 398                 *pos++ = 0;
 399         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
 400                 rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
 401         put_unaligned_le16(rx_flags, pos);
 402         pos += 2;
 403
 404         if (status->encoding == RX_ENC_HT) {
 405                 unsigned int stbc;
 406
 407                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
 408                 *pos++ = local->hw.radiotap_mcs_details;
 409                 *pos = 0;
 410                 if (status->enc_flags & RX_ENC_FLAG_SHORT_GI)
 411                         *pos |= IEEE80211_RADIOTAP_MCS_SGI;
 412                 if (status->bw == RATE_INFO_BW_40)
 413                         *pos |= IEEE80211_RADIOTAP_MCS_BW_40;
 414                 if (status->enc_flags & RX_ENC_FLAG_HT_GF)
 415                         *pos |= IEEE80211_RADIOTAP_MCS_FMT_GF;
 416                 if (status->enc_flags & RX_ENC_FLAG_LDPC)
 417                         *pos |= IEEE80211_RADIOTAP_MCS_FEC_LDPC;
 418                 stbc = (status->enc_flags & RX_ENC_FLAG_STBC_MASK) >> RX_ENC_FLAG_STBC_SHIFT;
 419                 *pos |= stbc << IEEE80211_RADIOTAP_MCS_STBC_SHIFT;
 420                 pos++;
 421                 *pos++ = status->rate_idx;
 422         }
 423
 424         if (status->flag & RX_FLAG_AMPDU_DETAILS) {
 425                 u16 flags = 0;
 426
 427                 /* ensure 4 byte alignment */
 428                 while ((pos - (u8 *)rthdr) & 3)
 429                         pos++;
 430                 rthdr->it_present |=
 431                         cpu_to_le32(1 << IEEE80211_RADIOTAP_AMPDU_STATUS);
 432                 put_unaligned_le32(status->ampdu_reference, pos);
 433                 pos += 4;
 434                 if (status->flag & RX_FLAG_AMPDU_LAST_KNOWN)
 435                         flags |= IEEE80211_RADIOTAP_AMPDU_LAST_KNOWN;
 436                 if (status->flag & RX_FLAG_AMPDU_IS_LAST)
 437                         flags |= IEEE80211_RADIOTAP_AMPDU_IS_LAST;
 438                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_ERROR)
 439                         flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_ERR;
 440                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
 441                         flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_KNOWN;
 442                 put_unaligned_le16(flags, pos);
 443                 pos += 2;
 444                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
 445                         *pos++ = status->ampdu_delimiter_crc;
 446                 else
 447                         *pos++ = 0;
 448                 *pos++ = 0;
 449         }
 450
 451         if (status->encoding == RX_ENC_VHT) {
 452                 u16 known = local->hw.radiotap_vht_details;
 453
 454                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_VHT);
 455                 put_unaligned_le16(known, pos);
 456                 pos += 2;
 457                 /* flags */
 458                 if (status->enc_flags & RX_ENC_FLAG_SHORT_GI)
 459                         *pos |= IEEE80211_RADIOTAP_VHT_FLAG_SGI;
 460                 /* in VHT, STBC is binary */
 461                 if (status->enc_flags & RX_ENC_FLAG_STBC_MASK)
 462                         *pos |= IEEE80211_RADIOTAP_VHT_FLAG_STBC;
 463                 if (status->enc_flags & RX_ENC_FLAG_BF)
 464                         *pos |= IEEE80211_RADIOTAP_VHT_FLAG_BEAMFORMED;
 465                 pos++;
 466                 /* bandwidth */
 467                 switch (status->bw) {
 468                 case RATE_INFO_BW_80:
 469                         *pos++ = 4;
 470                         break;
 471                 case RATE_INFO_BW_160:
 472                         *pos++ = 11;
 473                         break;
 474                 case RATE_INFO_BW_40:
 475                         *pos++ = 1;
 476                         break;
 477                 default:
 478                         *pos++ = 0;
 479                 }
 480                 /* MCS/NSS */
 481                 *pos = (status->rate_idx << 4) | status->nss;
 482                 pos += 4;
 483                 /* coding field */
 484                 if (status->enc_flags & RX_ENC_FLAG_LDPC)
 485                         *pos |= IEEE80211_RADIOTAP_CODING_LDPC_USER0;
 486                 pos++;
 487                 /* group ID */
 488                 pos++;
 489                 /* partial_aid */
 490                 pos += 2;
 491         }
 492
 493         if (local->hw.radiotap_timestamp.units_pos >= 0) {
 494                 u16 accuracy = 0;
 495                 u8 flags = IEEE80211_RADIOTAP_TIMESTAMP_FLAG_32BIT;
 496
 497                 rthdr->it_present |=
 498                         cpu_to_le32(1 << IEEE80211_RADIOTAP_TIMESTAMP);
 499
 500                 /* ensure 8 byte alignment */
 501                 while ((pos - (u8 *)rthdr) & 7)
 502                         pos++;
 503
 504                 put_unaligned_le64(status->device_timestamp, pos);
 505                 pos += sizeof(u64);
 506
 507                 if (local->hw.radiotap_timestamp.accuracy >= 0) {
 508                         accuracy = local->hw.radiotap_timestamp.accuracy;
 509                         flags |= IEEE80211_RADIOTAP_TIMESTAMP_FLAG_ACCURACY;
 510                 }
 511                 put_unaligned_le16(accuracy, pos);
 512                 pos += sizeof(u16);
 513
 514                 *pos++ = local->hw.radiotap_timestamp.units_pos;
 515                 *pos++ = flags;
 516         }
 517
 518         for_each_set_bit(chain, &chains, IEEE80211_MAX_CHAINS) {
 519                 *pos++ = status->chain_signal[chain];
 520                 *pos++ = chain;
 521         }
 522
 523         if (status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA) {
 524                 /* ensure 2 byte alignment for the vendor field as required */
 525                 if ((pos - (u8 *)rthdr) & 1)
 526                         *pos++ = 0;
 527                 *pos++ = rtap.oui[0];
 528                 *pos++ = rtap.oui[1];
 529                 *pos++ = rtap.oui[2];
 530                 *pos++ = rtap.subns;
 531                 put_unaligned_le16(rtap.len, pos);
 532                 pos += 2;
 533                 /* align the actual payload as requested */
 534                 while ((pos - (u8 *)rthdr) & (rtap.align - 1))
 535                         *pos++ = 0;
 536                 /* data (and possible padding) already follows */
 537         }
 538 }
 539
 540 static struct sk_buff *
 541 ieee80211_make_monitor_skb(struct ieee80211_local *local,
 542                            struct sk_buff **origskb,
 543                            struct ieee80211_rate *rate,
 544                            int rtap_vendor_space, bool use_origskb)
 545 {
 546         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(*origskb);
 547         int rt_hdrlen, needed_headroom;
 548         struct sk_buff *skb;
 549
 550         /* room for the radiotap header based on driver features */
 551         rt_hdrlen = ieee80211_rx_radiotap_hdrlen(local, status, *origskb);
 552         needed_headroom = rt_hdrlen - rtap_vendor_space;
 553
 554         if (use_origskb) {
 555                 /* only need to expand headroom if necessary */
 556                 skb = *origskb;
 557                 *origskb = NULL;
 558
 559                 /*
 560                  * This shouldn't trigger often because most devices have an
 561                  * RX header they pull before we get here, and that should
 562                  * be big enough for our radiotap information. We should
 563                  * probably export the length to drivers so that we can have
 564                  * them allocate enough headroom to start with.
 565                  */
 566                 if (skb_headroom(skb) < needed_headroom &&
 567                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
 568                         dev_kfree_skb(skb);
 569                         return NULL;
 570                 }
 571         } else {
 572                 /*
 573                  * Need to make a copy and possibly remove radiotap header
 574                  * and FCS from the original.
 575                  */
 576                 skb = skb_copy_expand(*origskb, needed_headroom, 0, GFP_ATOMIC);
 577
 578                 if (!skb)
 579                         return NULL;
 580         }
 581
 582         /* prepend radiotap information */
 583         ieee80211_add_rx_radiotap_header(local, skb, rate, rt_hdrlen, true);
 584
 585         skb_reset_mac_header(skb);
 586         skb->ip_summed = CHECKSUM_UNNECESSARY;
 587         skb->pkt_type = PACKET_OTHERHOST;
 588         skb->protocol = htons(ETH_P_802_2);
 589
 590         return skb;
 591 }
 592
 593 /*
 594  * This function copies a received frame to all monitor interfaces and
 595  * returns a cleaned-up SKB that no longer includes the FCS nor the
 596  * radiotap header the driver might have added.
 597  */
 598 static struct sk_buff *
 599 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
 600                      struct ieee80211_rate *rate)
 601 {
 602         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
 603         struct ieee80211_sub_if_data *sdata;
 604         struct sk_buff *monskb = NULL;
 605         int present_fcs_len = 0;
 606         unsigned int rtap_vendor_space = 0;
 607         struct ieee80211_sub_if_data *monitor_sdata =
 608                 rcu_dereference(local->monitor_sdata);
 609         bool only_monitor = false;
 610
 611         if (unlikely(status->flag & RX_FLAG_RADIOTAP_VENDOR_DATA)) {
 612                 struct ieee80211_vendor_radiotap *rtap = (void *)origskb->data;
 613
 614                 rtap_vendor_space = sizeof(*rtap) + rtap->len + rtap->pad;
 615         }
 616
 617         /*
 618          * First, we may need to make a copy of the skb because
 619          *  (1) we need to modify it for radiotap (if not present), and
 620          *  (2) the other RX handlers will modify the skb we got.
 621          *
 622          * We don't need to, of course, if we aren't going to return
 623          * the SKB because it has a bad FCS/PLCP checksum.
 624          */
 625
 626         if (ieee80211_hw_check(&local->hw, RX_INCLUDES_FCS)) {
 627                 if (unlikely(origskb->len <= FCS_LEN)) {
 628                         /* driver bug */
 629                         WARN_ON(1);
 630                         dev_kfree_skb(origskb);
 631                         return NULL;
 632                 }
 633                 present_fcs_len = FCS_LEN;
 634         }
 635
 636         /* ensure hdr->frame_control and vendor radiotap data are in skb head */
 637         if (!pskb_may_pull(origskb, 2 + rtap_vendor_space)) {
 638                 dev_kfree_skb(origskb);
 639                 return NULL;
 640         }
 641
 642         only_monitor = should_drop_frame(origskb, present_fcs_len,
 643                                          rtap_vendor_space);
 644
 645         if (!local->monitors || (status->flag & RX_FLAG_SKIP_MONITOR)) {
 646                 if (only_monitor) {
 647                         dev_kfree_skb(origskb);
 648                         return NULL;
 649                 }
 650
 651                 remove_monitor_info(origskb, present_fcs_len,
 652                                     rtap_vendor_space);
 653                 return origskb;
 654         }
 655
 656         ieee80211_handle_mu_mimo_mon(monitor_sdata, origskb, rtap_vendor_space);
 657
 658         list_for_each_entry_rcu(sdata, &local->mon_list, u.mntr.list) {
 659                 bool last_monitor = list_is_last(&sdata->u.mntr.list,
 660                                                  &local->mon_list);
 661
 662                 if (!monskb)
 663                         monskb = ieee80211_make_monitor_skb(local, &origskb,
 664                                                             rate,
 665                                                             rtap_vendor_space,
 666                                                             only_monitor &&
 667                                                             last_monitor);
 668
 669                 if (monskb) {
 670                         struct sk_buff *skb;
 671
 672                         if (last_monitor) {
 673                                 skb = monskb;
 674                                 monskb = NULL;
 675                         } else {
 676                                 skb = skb_clone(monskb, GFP_ATOMIC);
 677                         }
 678
 679                         if (skb) {
 680                                 skb->dev = sdata->dev;
 681                                 ieee80211_rx_stats(skb->dev, skb->len);
 682                                 netif_receive_skb(skb);
 683                         }
 684                 }
 685
 686                 if (last_monitor)
 687                         break;
 688         }
 689
 690         /* this happens if last_monitor was erroneously false */
 691         dev_kfree_skb(monskb);
 692
 693         /* ditto */
 694         if (!origskb)
 695                 return NULL;
 696
 697         remove_monitor_info(origskb, present_fcs_len, rtap_vendor_space);
 698         return origskb;
 699 }
 700
 701 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
 702 {
 703         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 704         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 705         int tid, seqno_idx, security_idx;
 706
 707         /* does the frame have a qos control field? */
 708         if (ieee80211_is_data_qos(hdr->frame_control)) {
 709                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 710                 /* frame has qos control */
 711                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
 712                 if (*qc & IEEE80211_QOS_CTL_A_MSDU_PRESENT)
 713                         status->rx_flags |= IEEE80211_RX_AMSDU;
 714
 715                 seqno_idx = tid;
 716                 security_idx = tid;
 717         } else {
 718                 /*
 719                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
 720                  *
 721                  *      Sequence numbers for management frames, QoS data
 722                  *      frames with a broadcast/multicast address in the
 723                  *      Address 1 field, and all non-QoS data frames sent
 724                  *      by QoS STAs are assigned using an additional single
 725                  *      modulo-4096 counter, [...]
 726                  *
 727                  * We also use that counter for non-QoS STAs.
 728                  */
 729                 seqno_idx = IEEE80211_NUM_TIDS;
 730                 security_idx = 0;
 731                 if (ieee80211_is_mgmt(hdr->frame_control))
 732                         security_idx = IEEE80211_NUM_TIDS;
 733                 tid = 0;
 734         }
 735
 736         rx->seqno_idx = seqno_idx;
 737         rx->security_idx = security_idx;
 738         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 739          * For now, set skb->priority to 0 for other cases. */
 740         rx->skb->priority = (tid > 7) ? 0 : tid;
 741 }
 742
 743 /**
 744  * DOC: Packet alignment
 745  *
 746  * Drivers always need to pass packets that are aligned to two-byte boundaries
 747  * to the stack.
 748  *
 749  * Additionally, should, if possible, align the payload data in a way that
 750  * guarantees that the contained IP header is aligned to a four-byte
 751  * boundary. In the case of regular frames, this simply means aligning the
 752  * payload to a four-byte boundary (because either the IP header is directly
 753  * contained, or IV/RFC1042 headers that have a length divisible by four are
 754  * in front of it).  If the payload data is not properly aligned and the
 755  * architecture doesn't support efficient unaligned operations, mac80211
 756  * will align the data.
 757  *
 758  * With A-MSDU frames, however, the payload data address must yield two modulo
 759  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
 760  * push the IP header further back to a multiple of four again. Thankfully, the
 761  * specs were sane enough this time around to require padding each A-MSDU
 762  * subframe to a length that is a multiple of four.
 763  *
 764  * Padding like Atheros hardware adds which is between the 802.11 header and
 765  * the payload is not supported, the driver is required to move the 802.11
 766  * header to be directly in front of the payload in that case.
 767  */
 768 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
 769 {
 770 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 771         WARN_ON_ONCE((unsigned long)rx->skb->data & 1);
 772 #endif
 773 }
 774
 775
 776 /* rx handlers */
 777
 778 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
 779 {
 780         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 781
 782         if (is_multicast_ether_addr(hdr->addr1))
 783                 return 0;
 784
 785         return ieee80211_is_robust_mgmt_frame(skb);
 786 }
 787
 788
 789 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
 790 {
 791         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 792
 793         if (!is_multicast_ether_addr(hdr->addr1))
 794                 return 0;
 795
 796         return ieee80211_is_robust_mgmt_frame(skb);
 797 }
 798
 799
 800 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
 801 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
 802 {
 803         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
 804         struct ieee80211_mmie *mmie;
 805         struct ieee80211_mmie_16 *mmie16;
 806
 807         if (skb->len < 24 + sizeof(*mmie) || !is_multicast_ether_addr(hdr->da))
 808                 return -1;
 809
 810         if (!ieee80211_is_robust_mgmt_frame(skb))
 811                 return -1; /* not a robust management frame */
 812
 813         mmie = (struct ieee80211_mmie *)
 814                 (skb->data + skb->len - sizeof(*mmie));
 815         if (mmie->element_id == WLAN_EID_MMIE &&
 816             mmie->length == sizeof(*mmie) - 2)
 817                 return le16_to_cpu(mmie->key_id);
 818
 819         mmie16 = (struct ieee80211_mmie_16 *)
 820                 (skb->data + skb->len - sizeof(*mmie16));
 821         if (skb->len >= 24 + sizeof(*mmie16) &&
 822             mmie16->element_id == WLAN_EID_MMIE &&
 823             mmie16->length == sizeof(*mmie16) - 2)
 824                 return le16_to_cpu(mmie16->key_id);
 825
 826         return -1;
 827 }
 828
 829 static int ieee80211_get_cs_keyid(const struct ieee80211_cipher_scheme *cs,
 830                                   struct sk_buff *skb)
 831 {
 832         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 833         __le16 fc;
 834         int hdrlen;
 835         u8 keyid;
 836
 837         fc = hdr->frame_control;
 838         hdrlen = ieee80211_hdrlen(fc);
 839
 840         if (skb->len < hdrlen + cs->hdr_len)
 841                 return -EINVAL;
 842
 843         skb_copy_bits(skb, hdrlen + cs->key_idx_off, &keyid, 1);
 844         keyid &= cs->key_idx_mask;
 845         keyid >>= cs->key_idx_shift;
 846
 847         return keyid;
 848 }
 849
 850 static ieee80211_rx_result ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
 851 {
 852         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 853         char *dev_addr = rx->sdata->vif.addr;
 854
 855         if (ieee80211_is_data(hdr->frame_control)) {
 856                 if (is_multicast_ether_addr(hdr->addr1)) {
 857                         if (ieee80211_has_tods(hdr->frame_control) ||
 858                             !ieee80211_has_fromds(hdr->frame_control))
 859                                 return RX_DROP_MONITOR;
 860                         if (ether_addr_equal(hdr->addr3, dev_addr))
 861                                 return RX_DROP_MONITOR;
 862                 } else {
 863                         if (!ieee80211_has_a4(hdr->frame_control))
 864                                 return RX_DROP_MONITOR;
 865                         if (ether_addr_equal(hdr->addr4, dev_addr))
 866                                 return RX_DROP_MONITOR;
 867                 }
 868         }
 869
 870         /* If there is not an established peer link and this is not a peer link
 871          * establisment frame, beacon or probe, drop the frame.
 872          */
 873
 874         if (!rx->sta || sta_plink_state(rx->sta) != NL80211_PLINK_ESTAB) {
 875                 struct ieee80211_mgmt *mgmt;
 876
 877                 if (!ieee80211_is_mgmt(hdr->frame_control))
 878                         return RX_DROP_MONITOR;
 879
 880                 if (ieee80211_is_action(hdr->frame_control)) {
 881                         u8 category;
 882
 883                         /* make sure category field is present */
 884                         if (rx->skb->len < IEEE80211_MIN_ACTION_SIZE)
 885                                 return RX_DROP_MONITOR;
 886
 887                         mgmt = (struct ieee80211_mgmt *)hdr;
 888                         category = mgmt->u.action.category;
 889                         if (category != WLAN_CATEGORY_MESH_ACTION &&
 890                             category != WLAN_CATEGORY_SELF_PROTECTED)
 891                                 return RX_DROP_MONITOR;
 892                         return RX_CONTINUE;
 893                 }
 894
 895                 if (ieee80211_is_probe_req(hdr->frame_control) ||
 896                     ieee80211_is_probe_resp(hdr->frame_control) ||
 897                     ieee80211_is_beacon(hdr->frame_control) ||
 898                     ieee80211_is_auth(hdr->frame_control))
 899                         return RX_CONTINUE;
 900
 901                 return RX_DROP_MONITOR;
 902         }
 903
 904         return RX_CONTINUE;
 905 }
 906
 907 static inline bool ieee80211_rx_reorder_ready(struct tid_ampdu_rx *tid_agg_rx,
 908                                               int index)
 909 {
 910         struct sk_buff_head *frames = &tid_agg_rx->reorder_buf[index];
 911         struct sk_buff *tail = skb_peek_tail(frames);
 912         struct ieee80211_rx_status *status;
 913
 914         if (tid_agg_rx->reorder_buf_filtered & BIT_ULL(index))
 915                 return true;
 916
 917         if (!tail)
 918                 return false;
 919
 920         status = IEEE80211_SKB_RXCB(tail);
 921         if (status->flag & RX_FLAG_AMSDU_MORE)
 922                 return false;
 923
 924         return true;
 925 }
 926
 927 static void ieee80211_release_reorder_frame(struct ieee80211_sub_if_data *sdata,
 928                                             struct tid_ampdu_rx *tid_agg_rx,
 929                                             int index,
 930                                             struct sk_buff_head *frames)
 931 {
 932         struct sk_buff_head *skb_list = &tid_agg_rx->reorder_buf[index];
 933         struct sk_buff *skb;
 934         struct ieee80211_rx_status *status;
 935
 936         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 937
 938         if (skb_queue_empty(skb_list))
 939                 goto no_frame;
 940
 941         if (!ieee80211_rx_reorder_ready(tid_agg_rx, index)) {
 942                 __skb_queue_purge(skb_list);
 943                 goto no_frame;
 944         }
 945
 946         /* release frames from the reorder ring buffer */
 947         tid_agg_rx->stored_mpdu_num--;
 948         while ((skb = __skb_dequeue(skb_list))) {
 949                 status = IEEE80211_SKB_RXCB(skb);
 950                 status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE;
 951                 __skb_queue_tail(frames, skb);
 952         }
 953
 954 no_frame:
 955         tid_agg_rx->reorder_buf_filtered &= ~BIT_ULL(index);
 956         tid_agg_rx->head_seq_num = ieee80211_sn_inc(tid_agg_rx->head_seq_num);
 957 }
 958
 959 static void ieee80211_release_reorder_frames(struct ieee80211_sub_if_data *sdata,
 960                                              struct tid_ampdu_rx *tid_agg_rx,
 961                                              u16 head_seq_num,
 962                                              struct sk_buff_head *frames)
 963 {
 964         int index;
 965
 966         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 967
 968         while (ieee80211_sn_less(tid_agg_rx->head_seq_num, head_seq_num)) {
 969                 index = tid_agg_rx->head_seq_num % tid_agg_rx->buf_size;
 970                 ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
 971                                                 frames);
 972         }
 973 }
 974
 975 /*
 976  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
 977  * the skb was added to the buffer longer than this time ago, the earlier
 978  * frames that have not yet been received are assumed to be lost and the skb
 979  * can be released for processing. This may also release other skb's from the
 980  * reorder buffer if there are no additional gaps between the frames.
 981  *
 982  * Callers must hold tid_agg_rx->reorder_lock.
 983  */
 984 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
 985
 986 static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata,
 987                                           struct tid_ampdu_rx *tid_agg_rx,
 988                                           struct sk_buff_head *frames)
 989 {
 990         int index, i, j;
 991
 992         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 993
 994         /* release the buffer until next missing frame */
 995         index = tid_agg_rx->head_seq_num % tid_agg_rx->buf_size;
 996         if (!ieee80211_rx_reorder_ready(tid_agg_rx, index) &&
 997             tid_agg_rx->stored_mpdu_num) {
 998                 /*
 999                  * No buffers ready to be released, but check whether any
1000                  * frames in the reorder buffer have timed out.
1001                  */
1002                 int skipped = 1;
1003                 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
1004                      j = (j + 1) % tid_agg_rx->buf_size) {
1005                         if (!ieee80211_rx_reorder_ready(tid_agg_rx, j)) {
1006                                 skipped++;
1007                                 continue;
1008                         }
1009                         if (skipped &&
1010                             !time_after(jiffies, tid_agg_rx->reorder_time[j] +
1011                                         HT_RX_REORDER_BUF_TIMEOUT))
1012                                 goto set_release_timer;
1013
1014                         /* don't leave incomplete A-MSDUs around */
1015                         for (i = (index + 1) % tid_agg_rx->buf_size; i != j;
1016                              i = (i + 1) % tid_agg_rx->buf_size)
1017                                 __skb_queue_purge(&tid_agg_rx->reorder_buf[i]);
1018
1019                         ht_dbg_ratelimited(sdata,
1020                                            "release an RX reorder frame due to timeout on earlier frames\n");
1021                         ieee80211_release_reorder_frame(sdata, tid_agg_rx, j,
1022                                                         frames);
1023
1024                         /*
1025                          * Increment the head seq# also for the skipped slots.
1026                          */
1027                         tid_agg_rx->head_seq_num =
1028                                 (tid_agg_rx->head_seq_num +
1029                                  skipped) & IEEE80211_SN_MASK;
1030                         skipped = 0;
1031                 }
1032         } else while (ieee80211_rx_reorder_ready(tid_agg_rx, index)) {
1033                 ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
1034                                                 frames);
1035                 index = tid_agg_rx->head_seq_num % tid_agg_rx->buf_size;
1036         }
1037
1038         if (tid_agg_rx->stored_mpdu_num) {
1039                 j = index = tid_agg_rx->head_seq_num % tid_agg_rx->buf_size;
1040
1041                 for (; j != (index - 1) % tid_agg_rx->buf_size;
1042                      j = (j + 1) % tid_agg_rx->buf_size) {
1043                         if (ieee80211_rx_reorder_ready(tid_agg_rx, j))
1044                                 break;
1045                 }
1046
1047  set_release_timer:
1048
1049                 if (!tid_agg_rx->removed)
1050                         mod_timer(&tid_agg_rx->reorder_timer,
1051                                   tid_agg_rx->reorder_time[j] + 1 +
1052                                   HT_RX_REORDER_BUF_TIMEOUT);
1053         } else {
1054                 del_timer(&tid_agg_rx->reorder_timer);
1055         }
1056 }
1057
1058 /*
1059  * As this function belongs to the RX path it must be under
1060  * rcu_read_lock protection. It returns false if the frame
1061  * can be processed immediately, true if it was consumed.
1062  */
1063 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_sub_if_data *sdata,
1064                                              struct tid_ampdu_rx *tid_agg_rx,
1065                                              struct sk_buff *skb,
1066                                              struct sk_buff_head *frames)
1067 {
1068         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1069         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1070         u16 sc = le16_to_cpu(hdr->seq_ctrl);
1071         u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
1072         u16 head_seq_num, buf_size;
1073         int index;
1074         bool ret = true;
1075
1076         spin_lock(&tid_agg_rx->reorder_lock);
1077
1078         /*
1079          * Offloaded BA sessions have no known starting sequence number so pick
1080          * one from first Rxed frame for this tid after BA was started.
1081          */
1082         if (unlikely(tid_agg_rx->auto_seq)) {
1083                 tid_agg_rx->auto_seq = false;
1084                 tid_agg_rx->ssn = mpdu_seq_num;
1085                 tid_agg_rx->head_seq_num = mpdu_seq_num;
1086         }
1087
1088         buf_size = tid_agg_rx->buf_size;
1089         head_seq_num = tid_agg_rx->head_seq_num;
1090
1091         /*
1092          * If the current MPDU's SN is smaller than the SSN, it shouldn't
1093          * be reordered.
1094          */
1095         if (unlikely(!tid_agg_rx->started)) {
1096                 if (ieee80211_sn_less(mpdu_seq_num, head_seq_num)) {
1097                         ret = false;
1098                         goto out;
1099                 }
1100                 tid_agg_rx->started = true;
1101         }
1102
1103         /* frame with out of date sequence number */
1104         if (ieee80211_sn_less(mpdu_seq_num, head_seq_num)) {
1105                 dev_kfree_skb(skb);
1106                 goto out;
1107         }
1108
1109         /*
1110          * If frame the sequence number exceeds our buffering window
1111          * size release some previous frames to make room for this one.
1112          */
1113         if (!ieee80211_sn_less(mpdu_seq_num, head_seq_num + buf_size)) {
1114                 head_seq_num = ieee80211_sn_inc(
1115                                 ieee80211_sn_sub(mpdu_seq_num, buf_size));
1116                 /* release stored frames up to new head to stack */
1117                 ieee80211_release_reorder_frames(sdata, tid_agg_rx,
1118                                                  head_seq_num, frames);
1119         }
1120
1121         /* Now the new frame is always in the range of the reordering buffer */
1122
1123         index = mpdu_seq_num % tid_agg_rx->buf_size;
1124
1125         /* check if we already stored this frame */
1126         if (ieee80211_rx_reorder_ready(tid_agg_rx, index)) {
1127                 dev_kfree_skb(skb);
1128                 goto out;
1129         }
1130
1131         /*
1132          * If the current MPDU is in the right order and nothing else
1133          * is stored we can process it directly, no need to buffer it.
1134          * If it is first but there's something stored, we may be able
1135          * to release frames after this one.
1136          */
1137         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
1138             tid_agg_rx->stored_mpdu_num == 0) {
1139                 if (!(status->flag & RX_FLAG_AMSDU_MORE))
1140                         tid_agg_rx->head_seq_num =
1141                                 ieee80211_sn_inc(tid_agg_rx->head_seq_num);
1142                 ret = false;
1143                 goto out;
1144         }
1145
1146         /* put the frame in the reordering buffer */
1147         __skb_queue_tail(&tid_agg_rx->reorder_buf[index], skb);
1148         if (!(status->flag & RX_FLAG_AMSDU_MORE)) {
1149                 tid_agg_rx->reorder_time[index] = jiffies;
1150                 tid_agg_rx->stored_mpdu_num++;
1151                 ieee80211_sta_reorder_release(sdata, tid_agg_rx, frames);
1152         }
1153
1154  out:
1155         spin_unlock(&tid_agg_rx->reorder_lock);
1156         return ret;
1157 }
1158
1159 /*
1160  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
1161  * true if the MPDU was buffered, false if it should be processed.
1162  */
1163 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
1164                                        struct sk_buff_head *frames)
1165 {
1166         struct sk_buff *skb = rx->skb;
1167         struct ieee80211_local *local = rx->local;
1168         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1169         struct sta_info *sta = rx->sta;
1170         struct tid_ampdu_rx *tid_agg_rx;
1171         u16 sc;
1172         u8 tid, ack_policy;
1173
1174         if (!ieee80211_is_data_qos(hdr->frame_control) ||
1175             is_multicast_ether_addr(hdr->addr1))
1176                 goto dont_reorder;
1177
1178         /*
1179          * filter the QoS data rx stream according to
1180          * STA/TID and check if this STA/TID is on aggregation
1181          */
1182
1183         if (!sta)
1184                 goto dont_reorder;
1185
1186         ack_policy = *ieee80211_get_qos_ctl(hdr) &
1187                      IEEE80211_QOS_CTL_ACK_POLICY_MASK;
1188         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
1189
1190         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
1191         if (!tid_agg_rx) {
1192                 if (ack_policy == IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
1193                     !test_bit(tid, rx->sta->ampdu_mlme.agg_session_valid) &&
1194                     !test_and_set_bit(tid, rx->sta->ampdu_mlme.unexpected_agg))
1195                         ieee80211_send_delba(rx->sdata, rx->sta->sta.addr, tid,
1196                                              WLAN_BACK_RECIPIENT,
1197                                              WLAN_REASON_QSTA_REQUIRE_SETUP);
1198                 goto dont_reorder;
1199         }
1200
1201         /* qos null data frames are excluded */
1202         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
1203                 goto dont_reorder;
1204
1205         /* not part of a BA session */
1206         if (ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
1207             ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_NORMAL)
1208                 goto dont_reorder;
1209
1210         /* new, potentially un-ordered, ampdu frame - process it */
1211
1212         /* reset session timer */
1213         if (tid_agg_rx->timeout)
1214                 tid_agg_rx->last_rx = jiffies;
1215
1216         /* if this mpdu is fragmented - terminate rx aggregation session */
1217         sc = le16_to_cpu(hdr->seq_ctrl);
1218         if (sc & IEEE80211_SCTL_FRAG) {
1219                 skb_queue_tail(&rx->sdata->skb_queue, skb);
1220                 ieee80211_queue_work(&local->hw, &rx->sdata->work);
1221                 return;
1222         }
1223
1224         /*
1225          * No locking needed -- we will only ever process one
1226          * RX packet at a time, and thus own tid_agg_rx. All
1227          * other code manipulating it needs to (and does) make
1228          * sure that we cannot get to it any more before doing
1229          * anything with it.
1230          */
1231         if (ieee80211_sta_manage_reorder_buf(rx->sdata, tid_agg_rx, skb,
1232                                              frames))
1233                 return;
1234
1235  dont_reorder:
1236         __skb_queue_tail(frames, skb);
1237 }
1238
1239 static ieee80211_rx_result debug_noinline
1240 ieee80211_rx_h_check_dup(struct ieee80211_rx_data *rx)
1241 {
1242         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1243         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1244
1245         if (status->flag & RX_FLAG_DUP_VALIDATED)
1246                 return RX_CONTINUE;
1247
1248         /*
1249          * Drop duplicate 802.11 retransmissions
1250          * (IEEE 802.11-2012: 9.3.2.10 "Duplicate detection and recovery")
1251          */
1252
1253         if (rx->skb->len < 24)
1254                 return RX_CONTINUE;
1255
1256         if (ieee80211_is_ctl(hdr->frame_control) ||
1257             ieee80211_is_qos_nullfunc(hdr->frame_control) ||
1258             is_multicast_ether_addr(hdr->addr1))
1259                 return RX_CONTINUE;
1260
1261         if (!rx->sta)
1262                 return RX_CONTINUE;
1263
1264         if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
1265                      rx->sta->last_seq_ctrl[rx->seqno_idx] == hdr->seq_ctrl)) {
1266                 I802_DEBUG_INC(rx->local->dot11FrameDuplicateCount);
1267                 rx->sta->rx_stats.num_duplicates++;
1268                 return RX_DROP_UNUSABLE;
1269         } else if (!(status->flag & RX_FLAG_AMSDU_MORE)) {
1270                 rx->sta->last_seq_ctrl[rx->seqno_idx] = hdr->seq_ctrl;
1271         }
1272
1273         return RX_CONTINUE;
1274 }
1275
1276 static ieee80211_rx_result debug_noinline
1277 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
1278 {
1279         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1280
1281         /* Drop disallowed frame classes based on STA auth/assoc state;
1282          * IEEE 802.11, Chap 5.5.
1283          *
1284          * mac80211 filters only based on association state, i.e. it drops
1285          * Class 3 frames from not associated stations. hostapd sends
1286          * deauth/disassoc frames when needed. In addition, hostapd is
1287          * responsible for filtering on both auth and assoc states.
1288          */
1289
1290         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
1291                 return ieee80211_rx_mesh_check(rx);
1292
1293         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
1294                       ieee80211_is_pspoll(hdr->frame_control)) &&
1295                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
1296                      rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
1297                      rx->sdata->vif.type != NL80211_IFTYPE_OCB &&
1298                      (!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_ASSOC)))) {
1299                 /*
1300                  * accept port control frames from the AP even when it's not
1301                  * yet marked ASSOC to prevent a race where we don't set the
1302                  * assoc bit quickly enough before it sends the first frame
1303                  */
1304                 if (rx->sta && rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1305                     ieee80211_is_data_present(hdr->frame_control)) {
1306                         unsigned int hdrlen;
1307                         __be16 ethertype;
1308
1309                         hdrlen = ieee80211_hdrlen(hdr->frame_control);
1310
1311                         if (rx->skb->len < hdrlen + 8)
1312                                 return RX_DROP_MONITOR;
1313
1314                         skb_copy_bits(rx->skb, hdrlen + 6, &ethertype, 2);
1315                         if (ethertype == rx->sdata->control_port_protocol)
1316                                 return RX_CONTINUE;
1317                 }
1318
1319                 if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
1320                     cfg80211_rx_spurious_frame(rx->sdata->dev,
1321                                                hdr->addr2,
1322                                                GFP_ATOMIC))
1323                         return RX_DROP_UNUSABLE;
1324
1325                 return RX_DROP_MONITOR;
1326         }
1327
1328         return RX_CONTINUE;
1329 }
1330
1331
1332 static ieee80211_rx_result debug_noinline
1333 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1334 {
1335         struct ieee80211_local *local;
1336         struct ieee80211_hdr *hdr;
1337         struct sk_buff *skb;
1338
1339         local = rx->local;
1340         skb = rx->skb;
1341         hdr = (struct ieee80211_hdr *) skb->data;
1342
1343         if (!local->pspolling)
1344                 return RX_CONTINUE;
1345
1346         if (!ieee80211_has_fromds(hdr->frame_control))
1347                 /* this is not from AP */
1348                 return RX_CONTINUE;
1349
1350         if (!ieee80211_is_data(hdr->frame_control))
1351                 return RX_CONTINUE;
1352
1353         if (!ieee80211_has_moredata(hdr->frame_control)) {
1354                 /* AP has no more frames buffered for us */
1355                 local->pspolling = false;
1356                 return RX_CONTINUE;
1357         }
1358
1359         /* more data bit is set, let's request a new frame from the AP */
1360         ieee80211_send_pspoll(local, rx->sdata);
1361
1362         return RX_CONTINUE;
1363 }
1364
1365 static void sta_ps_start(struct sta_info *sta)
1366 {
1367         struct ieee80211_sub_if_data *sdata = sta->sdata;
1368         struct ieee80211_local *local = sdata->local;
1369         struct ps_data *ps;
1370         int tid;
1371
1372         if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
1373             sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1374                 ps = &sdata->bss->ps;
1375         else
1376                 return;
1377
1378         atomic_inc(&ps->num_sta_ps);
1379         set_sta_flag(sta, WLAN_STA_PS_STA);
1380         if (!ieee80211_hw_check(&local->hw, AP_LINK_PS))
1381                 drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1382         ps_dbg(sdata, "STA %pM aid %d enters power save mode\n",
1383                sta->sta.addr, sta->sta.aid);
1384
1385         ieee80211_clear_fast_xmit(sta);
1386
1387         if (!sta->sta.txq[0])
1388                 return;
1389
1390         for (tid = 0; tid < ARRAY_SIZE(sta->sta.txq); tid++) {
1391                 if (txq_has_queue(sta->sta.txq[tid]))
1392                         set_bit(tid, &sta->txq_buffered_tids);
1393                 else
1394                         clear_bit(tid, &sta->txq_buffered_tids);
1395         }
1396 }
1397
1398 static void sta_ps_end(struct sta_info *sta)
1399 {
1400         ps_dbg(sta->sdata, "STA %pM aid %d exits power save mode\n",
1401                sta->sta.addr, sta->sta.aid);
1402
1403         if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) {
1404                 /*
1405                  * Clear the flag only if the other one is still set
1406                  * so that the TX path won't start TX'ing new frames
1407                  * directly ... In the case that the driver flag isn't
1408                  * set ieee80211_sta_ps_deliver_wakeup() will clear it.
1409                  */
1410                 clear_sta_flag(sta, WLAN_STA_PS_STA);
1411                 ps_dbg(sta->sdata, "STA %pM aid %d driver-ps-blocked\n",
1412                        sta->sta.addr, sta->sta.aid);
1413                 return;
1414         }
1415
1416         set_sta_flag(sta, WLAN_STA_PS_DELIVER);
1417         clear_sta_flag(sta, WLAN_STA_PS_STA);
1418         ieee80211_sta_ps_deliver_wakeup(sta);
1419 }
1420
1421 int ieee80211_sta_ps_transition(struct ieee80211_sta *pubsta, bool start)
1422 {
1423         struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
1424         bool in_ps;
1425
1426         WARN_ON(!ieee80211_hw_check(&sta->local->hw, AP_LINK_PS));
1427
1428         /* Don't let the same PS state be set twice */
1429         in_ps = test_sta_flag(sta, WLAN_STA_PS_STA);
1430         if ((start && in_ps) || (!start && !in_ps))
1431                 return -EINVAL;
1432
1433         if (start)
1434                 sta_ps_start(sta);
1435         else
1436                 sta_ps_end(sta);
1437
1438         return 0;
1439 }
1440 EXPORT_SYMBOL(ieee80211_sta_ps_transition);
1441
1442 void ieee80211_sta_pspoll(struct ieee80211_sta *pubsta)
1443 {
1444         struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
1445
1446         if (test_sta_flag(sta, WLAN_STA_SP))
1447                 return;
1448
1449         if (!test_sta_flag(sta, WLAN_STA_PS_DRIVER))
1450                 ieee80211_sta_ps_deliver_poll_response(sta);
1451         else
1452                 set_sta_flag(sta, WLAN_STA_PSPOLL);
1453 }
1454 EXPORT_SYMBOL(ieee80211_sta_pspoll);
1455
1456 void ieee80211_sta_uapsd_trigger(struct ieee80211_sta *pubsta, u8 tid)
1457 {
1458         struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
1459         int ac = ieee80211_ac_from_tid(tid);
1460
1461         /*
1462          * If this AC is not trigger-enabled do nothing unless the
1463          * driver is calling us after it already checked.
1464          *
1465          * NB: This could/should check a separate bitmap of trigger-
1466          * enabled queues, but for now we only implement uAPSD w/o
1467          * TSPEC changes to the ACs, so they're always the same.
1468          */
1469         if (!(sta->sta.uapsd_queues & ieee80211_ac_to_qos_mask[ac]) &&
1470             tid != IEEE80211_NUM_TIDS)
1471                 return;
1472
1473         /* if we are in a service period, do nothing */
1474         if (test_sta_flag(sta, WLAN_STA_SP))
1475                 return;
1476
1477         if (!test_sta_flag(sta, WLAN_STA_PS_DRIVER))
1478                 ieee80211_sta_ps_deliver_uapsd(sta);
1479         else
1480                 set_sta_flag(sta, WLAN_STA_UAPSD);
1481 }
1482 EXPORT_SYMBOL(ieee80211_sta_uapsd_trigger);
1483
1484 static ieee80211_rx_result debug_noinline
1485 ieee80211_rx_h_uapsd_and_pspoll(struct ieee80211_rx_data *rx)
1486 {
1487         struct ieee80211_sub_if_data *sdata = rx->sdata;
1488         struct ieee80211_hdr *hdr = (void *)rx->skb->data;
1489         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1490
1491         if (!rx->sta)
1492                 return RX_CONTINUE;
1493
1494         if (sdata->vif.type != NL80211_IFTYPE_AP &&
1495             sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
1496                 return RX_CONTINUE;
1497
1498         /*
1499          * The device handles station powersave, so don't do anything about
1500          * uAPSD and PS-Poll frames (the latter shouldn't even come up from
1501          * it to mac80211 since they're handled.)
1502          */
1503         if (ieee80211_hw_check(&sdata->local->hw, AP_LINK_PS))
1504                 return RX_CONTINUE;
1505
1506         /*
1507          * Don't do anything if the station isn't already asleep. In
1508          * the uAPSD case, the station will probably be marked asleep,
1509          * in the PS-Poll case the station must be confused ...
1510          */
1511         if (!test_sta_flag(rx->sta, WLAN_STA_PS_STA))
1512                 return RX_CONTINUE;
1513
1514         if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) {
1515                 ieee80211_sta_pspoll(&rx->sta->sta);
1516
1517                 /* Free PS Poll skb here instead of returning RX_DROP that would
1518                  * count as an dropped frame. */
1519                 dev_kfree_skb(rx->skb);
1520
1521                 return RX_QUEUED;
1522         } else if (!ieee80211_has_morefrags(hdr->frame_control) &&
1523                    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1524                    ieee80211_has_pm(hdr->frame_control) &&
1525                    (ieee80211_is_data_qos(hdr->frame_control) ||
1526                     ieee80211_is_qos_nullfunc(hdr->frame_control))) {
1527                 u8 tid;
1528
1529                 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
1530
1531                 ieee80211_sta_uapsd_trigger(&rx->sta->sta, tid);
1532         }
1533
1534         return RX_CONTINUE;
1535 }
1536
1537 static ieee80211_rx_result debug_noinline
1538 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1539 {
1540         struct sta_info *sta = rx->sta;
1541         struct sk_buff *skb = rx->skb;
1542         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1543         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1544         int i;
1545
1546         if (!sta)
1547                 return RX_CONTINUE;
1548
1549         /*
1550          * Update last_rx only for IBSS packets which are for the current
1551          * BSSID and for station already AUTHORIZED to avoid keeping the
1552          * current IBSS network alive in cases where other STAs start
1553          * using different BSSID. This will also give the station another
1554          * chance to restart the authentication/authorization in case
1555          * something went wrong the first time.
1556          */
1557         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1558                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1559                                                 NL80211_IFTYPE_ADHOC);
1560                 if (ether_addr_equal(bssid, rx->sdata->u.ibss.bssid) &&
1561                     test_sta_flag(sta, WLAN_STA_AUTHORIZED)) {
1562                         sta->rx_stats.last_rx = jiffies;
1563                         if (ieee80211_is_data(hdr->frame_control) &&
1564                             !is_multicast_ether_addr(hdr->addr1))
1565                                 sta->rx_stats.last_rate =
1566                                         sta_stats_encode_rate(status);
1567                 }
1568         } else if (rx->sdata->vif.type == NL80211_IFTYPE_OCB) {
1569                 sta->rx_stats.last_rx = jiffies;
1570         } else if (!is_multicast_ether_addr(hdr->addr1)) {
1571                 /*
1572                  * Mesh beacons will update last_rx when if they are found to
1573                  * match the current local configuration when processed.
1574                  */
1575                 sta->rx_stats.last_rx = jiffies;
1576                 if (ieee80211_is_data(hdr->frame_control))
1577                         sta->rx_stats.last_rate = sta_stats_encode_rate(status);
1578         }
1579
1580         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1581                 ieee80211_sta_rx_notify(rx->sdata, hdr);
1582
1583         sta->rx_stats.fragments++;
1584
1585         u64_stats_update_begin(&rx->sta->rx_stats.syncp);
1586         sta->rx_stats.bytes += rx->skb->len;
1587         u64_stats_update_end(&rx->sta->rx_stats.syncp);
1588
1589         if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
1590                 sta->rx_stats.last_signal = status->signal;
1591                 ewma_signal_add(&sta->rx_stats_avg.signal, -status->signal);
1592         }
1593
1594         if (status->chains) {
1595                 sta->rx_stats.chains = status->chains;
1596                 for (i = 0; i < ARRAY_SIZE(status->chain_signal); i++) {
1597                         int signal = status->chain_signal[i];
1598
1599                         if (!(status->chains & BIT(i)))
1600                                 continue;
1601
1602                         sta->rx_stats.chain_signal_last[i] = signal;
1603                         ewma_signal_add(&sta->rx_stats_avg.chain_signal[i],
1604                                         -signal);
1605                 }
1606         }
1607
1608         /*
1609          * Change STA power saving mode only at the end of a frame
1610          * exchange sequence, and only for a data or management
1611          * frame as specified in IEEE 802.11-2016 11.2.3.2
1612          */
1613         if (!ieee80211_hw_check(&sta->local->hw, AP_LINK_PS) &&
1614             !ieee80211_has_morefrags(hdr->frame_control) &&
1615             (ieee80211_is_mgmt(hdr->frame_control) ||
1616              ieee80211_is_data(hdr->frame_control)) &&
1617             !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1618             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1619              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1620                 if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
1621                         if (!ieee80211_has_pm(hdr->frame_control))
1622                                 sta_ps_end(sta);
1623                 } else {
1624                         if (ieee80211_has_pm(hdr->frame_control))
1625                                 sta_ps_start(sta);
1626                 }
1627         }
1628
1629         /* mesh power save support */
1630         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
1631                 ieee80211_mps_rx_h_sta_process(sta, hdr);
1632
1633         /*
1634          * Drop (qos-)data::nullfunc frames silently, since they
1635          * are used only to control station power saving mode.
1636          */
1637         if (ieee80211_is_nullfunc(hdr->frame_control) ||
1638             ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1639                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1640
1641                 /*
1642                  * If we receive a 4-addr nullfunc frame from a STA
1643                  * that was not moved to a 4-addr STA vlan yet send
1644                  * the event to userspace and for older hostapd drop
1645                  * the frame to the monitor interface.
1646                  */
1647                 if (ieee80211_has_a4(hdr->frame_control) &&
1648                     (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1649                      (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1650                       !rx->sdata->u.vlan.sta))) {
1651                         if (!test_and_set_sta_flag(sta, WLAN_STA_4ADDR_EVENT))
1652                                 cfg80211_rx_unexpected_4addr_frame(
1653                                         rx->sdata->dev, sta->sta.addr,
1654                                         GFP_ATOMIC);
1655                         return RX_DROP_MONITOR;
1656                 }
1657                 /*
1658                  * Update counter and free packet here to avoid
1659                  * counting this as a dropped packed.
1660                  */
1661                 sta->rx_stats.packets++;
1662                 dev_kfree_skb(rx->skb);
1663                 return RX_QUEUED;
1664         }
1665
1666         return RX_CONTINUE;
1667 } /* ieee80211_rx_h_sta_process */
1668
1669 static ieee80211_rx_result debug_noinline
1670 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
1671 {
1672         struct sk_buff *skb = rx->skb;
1673         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1674         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1675         int keyidx;
1676         int hdrlen;
1677         ieee80211_rx_result result = RX_DROP_UNUSABLE;
1678         struct ieee80211_key *sta_ptk = NULL;
1679         int mmie_keyidx = -1;
1680         __le16 fc;
1681         const struct ieee80211_cipher_scheme *cs = NULL;
1682
1683         /*
1684          * Key selection 101
1685          *
1686          * There are four types of keys:
1687          *  - GTK (group keys)
1688          *  - IGTK (group keys for management frames)
1689          *  - PTK (pairwise keys)
1690          *  - STK (station-to-station pairwise keys)
1691          *
1692          * When selecting a key, we have to distinguish between multicast
1693          * (including broadcast) and unicast frames, the latter can only
1694          * use PTKs and STKs while the former always use GTKs and IGTKs.
1695          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
1696          * unicast frames can also use key indices like GTKs. Hence, if we
1697          * don't have a PTK/STK we check the key index for a WEP key.
1698          *
1699          * Note that in a regular BSS, multicast frames are sent by the
1700          * AP only, associated stations unicast the frame to the AP first
1701          * which then multicasts it on their behalf.
1702          *
1703          * There is also a slight problem in IBSS mode: GTKs are negotiated
1704          * with each station, that is something we don't currently handle.
1705          * The spec seems to expect that one negotiates the same key with
1706          * every station but there's no such requirement; VLANs could be
1707          * possible.
1708          */
1709
1710         /* start without a key */
1711         rx->key = NULL;
1712         fc = hdr->frame_control;
1713
1714         if (rx->sta) {
1715                 int keyid = rx->sta->ptk_idx;
1716
1717                 if (ieee80211_has_protected(fc) && rx->sta->cipher_scheme) {
1718                         cs = rx->sta->cipher_scheme;
1719                         keyid = ieee80211_get_cs_keyid(cs, rx->skb);
1720                         if (unlikely(keyid < 0))
1721                                 return RX_DROP_UNUSABLE;
1722                 }
1723                 sta_ptk = rcu_dereference(rx->sta->ptk[keyid]);
1724         }
1725
1726         if (!ieee80211_has_protected(fc))
1727                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
1728
1729         if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
1730                 rx->key = sta_ptk;
1731                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1732                     (status->flag & RX_FLAG_IV_STRIPPED))
1733                         return RX_CONTINUE;
1734                 /* Skip decryption if the frame is not protected. */
1735                 if (!ieee80211_has_protected(fc))
1736                         return RX_CONTINUE;
1737         } else if (mmie_keyidx >= 0) {
1738                 /* Broadcast/multicast robust management frame / BIP */
1739                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1740                     (status->flag & RX_FLAG_IV_STRIPPED))
1741                         return RX_CONTINUE;
1742
1743                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
1744                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
1745                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
1746                 if (rx->sta) {
1747                         if (ieee80211_is_group_privacy_action(skb) &&
1748                             test_sta_flag(rx->sta, WLAN_STA_MFP))
1749                                 return RX_DROP_MONITOR;
1750
1751                         rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
1752                 }
1753                 if (!rx->key)
1754                         rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
1755         } else if (!ieee80211_has_protected(fc)) {
1756                 /*
1757                  * The frame was not protected, so skip decryption. However, we
1758                  * need to set rx->key if there is a key that could have been
1759                  * used so that the frame may be dropped if encryption would
1760                  * have been expected.
1761                  */
1762                 struct ieee80211_key *key = NULL;
1763                 struct ieee80211_sub_if_data *sdata = rx->sdata;
1764                 int i;
1765
1766                 if (ieee80211_is_mgmt(fc) &&
1767                     is_multicast_ether_addr(hdr->addr1) &&
1768                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
1769                         rx->key = key;
1770                 else {
1771                         if (rx->sta) {
1772                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1773                                         key = rcu_dereference(rx->sta->gtk[i]);
1774                                         if (key)
1775                                                 break;
1776                                 }
1777                         }
1778                         if (!key) {
1779                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1780                                         key = rcu_dereference(sdata->keys[i]);
1781                                         if (key)
1782                                                 break;
1783                                 }
1784                         }
1785                         if (key)
1786                                 rx->key = key;
1787                 }
1788                 return RX_CONTINUE;
1789         } else {
1790                 u8 keyid;
1791
1792                 /*
1793                  * The device doesn't give us the IV so we won't be
1794                  * able to look up the key. That's ok though, we
1795                  * don't need to decrypt the frame, we just won't
1796                  * be able to keep statistics accurate.
1797                  * Except for key threshold notifications, should
1798                  * we somehow allow the driver to tell us which key
1799                  * the hardware used if this flag is set?
1800                  */
1801                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1802                     (status->flag & RX_FLAG_IV_STRIPPED))
1803                         return RX_CONTINUE;
1804
1805                 hdrlen = ieee80211_hdrlen(fc);
1806
1807                 if (cs) {
1808                         keyidx = ieee80211_get_cs_keyid(cs, rx->skb);
1809
1810                         if (unlikely(keyidx < 0))
1811                                 return RX_DROP_UNUSABLE;
1812                 } else {
1813                         if (rx->skb->len < 8 + hdrlen)
1814                                 return RX_DROP_UNUSABLE; /* TODO: count this? */
1815                         /*
1816                          * no need to call ieee80211_wep_get_keyidx,
1817                          * it verifies a bunch of things we've done already
1818                          */
1819                         skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
1820                         keyidx = keyid >> 6;
1821                 }
1822
1823                 /* check per-station GTK first, if multicast packet */
1824                 if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
1825                         rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
1826
1827                 /* if not found, try default key */
1828                 if (!rx->key) {
1829                         rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
1830
1831                         /*
1832                          * RSNA-protected unicast frames should always be
1833                          * sent with pairwise or station-to-station keys,
1834                          * but for WEP we allow using a key index as well.
1835                          */
1836                         if (rx->key &&
1837                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1838                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1839                             !is_multicast_ether_addr(hdr->addr1))
1840                                 rx->key = NULL;
1841                 }
1842         }
1843
1844         if (rx->key) {
1845                 if (unlikely(rx->key->flags & KEY_FLAG_TAINTED))
1846                         return RX_DROP_MONITOR;
1847
1848                 /* TODO: add threshold stuff again */
1849         } else {
1850                 return RX_DROP_MONITOR;
1851         }
1852
1853         switch (rx->key->conf.cipher) {
1854         case WLAN_CIPHER_SUITE_WEP40:
1855         case WLAN_CIPHER_SUITE_WEP104:
1856                 result = ieee80211_crypto_wep_decrypt(rx);
1857                 break;
1858         case WLAN_CIPHER_SUITE_TKIP:
1859                 result = ieee80211_crypto_tkip_decrypt(rx);
1860                 break;
1861         case WLAN_CIPHER_SUITE_CCMP:
1862                 result = ieee80211_crypto_ccmp_decrypt(
1863                         rx, IEEE80211_CCMP_MIC_LEN);
1864                 break;
1865         case WLAN_CIPHER_SUITE_CCMP_256:
1866                 result = ieee80211_crypto_ccmp_decrypt(
1867                         rx, IEEE80211_CCMP_256_MIC_LEN);
1868                 break;
1869         case WLAN_CIPHER_SUITE_AES_CMAC:
1870                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
1871                 break;
1872         case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1873                 result = ieee80211_crypto_aes_cmac_256_decrypt(rx);
1874                 break;
1875         case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1876         case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1877                 result = ieee80211_crypto_aes_gmac_decrypt(rx);
1878                 break;
1879         case WLAN_CIPHER_SUITE_GCMP:
1880         case WLAN_CIPHER_SUITE_GCMP_256:
1881                 result = ieee80211_crypto_gcmp_decrypt(rx);
1882                 break;
1883         default:
1884                 result = ieee80211_crypto_hw_decrypt(rx);
1885         }
1886
1887         /* the hdr variable is invalid after the decrypt handlers */
1888
1889         /* either the frame has been decrypted or will be dropped */
1890         status->flag |= RX_FLAG_DECRYPTED;
1891
1892         return result;
1893 }
1894
1895 static inline struct ieee80211_fragment_entry *
1896 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1897                          unsigned int frag, unsigned int seq, int rx_queue,
1898                          struct sk_buff **skb)
1899 {
1900         struct ieee80211_fragment_entry *entry;
1901
1902         entry = &sdata->fragments[sdata->fragment_next++];
1903         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1904                 sdata->fragment_next = 0;
1905
1906         if (!skb_queue_empty(&entry->skb_list))
1907                 __skb_queue_purge(&entry->skb_list);
1908
1909         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1910         *skb = NULL;
1911         entry->first_frag_time = jiffies;
1912         entry->seq = seq;
1913         entry->rx_queue = rx_queue;
1914         entry->last_frag = frag;
1915         entry->check_sequential_pn = false;
1916         entry->extra_len = 0;
1917
1918         return entry;
1919 }
1920
1921 static inline struct ieee80211_fragment_entry *
1922 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1923                           unsigned int frag, unsigned int seq,
1924                           int rx_queue, struct ieee80211_hdr *hdr)
1925 {
1926         struct ieee80211_fragment_entry *entry;
1927         int i, idx;
1928
1929         idx = sdata->fragment_next;
1930         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1931                 struct ieee80211_hdr *f_hdr;
1932
1933                 idx--;
1934                 if (idx < 0)
1935                         idx = IEEE80211_FRAGMENT_MAX - 1;
1936
1937                 entry = &sdata->fragments[idx];
1938                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1939                     entry->rx_queue != rx_queue ||
1940                     entry->last_frag + 1 != frag)
1941                         continue;
1942
1943                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1944
1945                 /*
1946                  * Check ftype and addresses are equal, else check next fragment
1947                  */
1948                 if (((hdr->frame_control ^ f_hdr->frame_control) &
1949                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1950                     !ether_addr_equal(hdr->addr1, f_hdr->addr1) ||
1951                     !ether_addr_equal(hdr->addr2, f_hdr->addr2))
1952                         continue;
1953
1954                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1955                         __skb_queue_purge(&entry->skb_list);
1956                         continue;
1957                 }
1958                 return entry;
1959         }
1960
1961         return NULL;
1962 }
1963
1964 static ieee80211_rx_result debug_noinline
1965 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1966 {
1967         struct ieee80211_hdr *hdr;
1968         u16 sc;
1969         __le16 fc;
1970         unsigned int frag, seq;
1971         struct ieee80211_fragment_entry *entry;
1972         struct sk_buff *skb;
1973
1974         hdr = (struct ieee80211_hdr *)rx->skb->data;
1975         fc = hdr->frame_control;
1976
1977         if (ieee80211_is_ctl(fc))
1978                 return RX_CONTINUE;
1979
1980         sc = le16_to_cpu(hdr->seq_ctrl);
1981         frag = sc & IEEE80211_SCTL_FRAG;
1982
1983         if (is_multicast_ether_addr(hdr->addr1)) {
1984                 I802_DEBUG_INC(rx->local->dot11MulticastReceivedFrameCount);
1985                 goto out_no_led;
1986         }
1987
1988         if (likely(!ieee80211_has_morefrags(fc) && frag == 0))
1989                 goto out;
1990
1991         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1992
1993         if (skb_linearize(rx->skb))
1994                 return RX_DROP_UNUSABLE;
1995
1996         /*
1997          *  skb_linearize() might change the skb->data and
1998          *  previously cached variables (in this case, hdr) need to
1999          *  be refreshed with the new data.
2000          */
2001         hdr = (struct ieee80211_hdr *)rx->skb->data;
2002         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
2003
2004         if (frag == 0) {
2005                 /* This is the first fragment of a new frame. */
2006                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
2007                                                  rx->seqno_idx, &(rx->skb));
2008                 if (rx->key &&
2009                     (rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP ||
2010                      rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP_256 ||
2011                      rx->key->conf.cipher == WLAN_CIPHER_SUITE_GCMP ||
2012                      rx->key->conf.cipher == WLAN_CIPHER_SUITE_GCMP_256) &&
2013                     ieee80211_has_protected(fc)) {
2014                         int queue = rx->security_idx;
2015
2016                         /* Store CCMP/GCMP PN so that we can verify that the
2017                          * next fragment has a sequential PN value.
2018                          */
2019                         entry->check_sequential_pn = true;
2020                         memcpy(entry->last_pn,
2021                                rx->key->u.ccmp.rx_pn[queue],
2022                                IEEE80211_CCMP_PN_LEN);
2023                         BUILD_BUG_ON(offsetof(struct ieee80211_key,
2024                                               u.ccmp.rx_pn) !=
2025                                      offsetof(struct ieee80211_key,
2026                                               u.gcmp.rx_pn));
2027                         BUILD_BUG_ON(sizeof(rx->key->u.ccmp.rx_pn[queue]) !=
2028                                      sizeof(rx->key->u.gcmp.rx_pn[queue]));
2029                         BUILD_BUG_ON(IEEE80211_CCMP_PN_LEN !=
2030                                      IEEE80211_GCMP_PN_LEN);
2031                 }
2032                 return RX_QUEUED;
2033         }
2034
2035         /* This is a fragment for a frame that should already be pending in
2036          * fragment cache. Add this fragment to the end of the pending entry.
2037          */
2038         entry = ieee80211_reassemble_find(rx->sdata, frag, seq,
2039                                           rx->seqno_idx, hdr);
2040         if (!entry) {
2041                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
2042                 return RX_DROP_MONITOR;
2043         }
2044
2045         /* "The receiver shall discard MSDUs and MMPDUs whose constituent
2046          *  MPDU PN values are not incrementing in steps of 1."
2047          * see IEEE P802.11-REVmc/D5.0, 12.5.3.4.4, item d (for CCMP)
2048          * and IEEE P802.11-REVmc/D5.0, 12.5.5.4.4, item d (for GCMP)
2049          */
2050         if (entry->check_sequential_pn) {
2051                 int i;
2052                 u8 pn[IEEE80211_CCMP_PN_LEN], *rpn;
2053                 int queue;
2054
2055                 if (!rx->key ||
2056                     (rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP &&
2057                      rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP_256 &&
2058                      rx->key->conf.cipher != WLAN_CIPHER_SUITE_GCMP &&
2059                      rx->key->conf.cipher != WLAN_CIPHER_SUITE_GCMP_256))
2060                         return RX_DROP_UNUSABLE;
2061                 memcpy(pn, entry->last_pn, IEEE80211_CCMP_PN_LEN);
2062                 for (i = IEEE80211_CCMP_PN_LEN - 1; i >= 0; i--) {
2063                         pn[i]++;
2064                         if (pn[i])
2065                                 break;
2066                 }
2067                 queue = rx->security_idx;
2068                 rpn = rx->key->u.ccmp.rx_pn[queue];
2069                 if (memcmp(pn, rpn, IEEE80211_CCMP_PN_LEN))
2070                         return RX_DROP_UNUSABLE;
2071                 memcpy(entry->last_pn, pn, IEEE80211_CCMP_PN_LEN);
2072         }
2073
2074         skb_pull(rx->skb, ieee80211_hdrlen(fc));
2075         __skb_queue_tail(&entry->skb_list, rx->skb);
2076         entry->last_frag = frag;
2077         entry->extra_len += rx->skb->len;
2078         if (ieee80211_has_morefrags(fc)) {
2079                 rx->skb = NULL;
2080                 return RX_QUEUED;
2081         }
2082
2083         rx->skb = __skb_dequeue(&entry->skb_list);
2084         if (skb_tailroom(rx->skb) < entry->extra_len) {
2085                 I802_DEBUG_INC(rx->local->rx_expand_skb_head_defrag);
2086                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
2087                                               GFP_ATOMIC))) {
2088                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
2089                         __skb_queue_purge(&entry->skb_list);
2090                         return RX_DROP_UNUSABLE;
2091                 }
2092         }
2093         while ((skb = __skb_dequeue(&entry->skb_list))) {
2094                 skb_put_data(rx->skb, skb->data, skb->len);
2095                 dev_kfree_skb(skb);
2096         }
2097
2098  out:
2099         ieee80211_led_rx(rx->local);
2100  out_no_led:
2101         if (rx->sta)
2102                 rx->sta->rx_stats.packets++;
2103         return RX_CONTINUE;
2104 }
2105
2106 static int ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
2107 {
2108         if (unlikely(!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_AUTHORIZED)))
2109                 return -EACCES;
2110
2111         return 0;
2112 }
2113
2114 static int ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
2115 {
2116         struct sk_buff *skb = rx->skb;
2117         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2118
2119         /*
2120          * Pass through unencrypted frames if the hardware has
2121          * decrypted them already.
2122          */
2123         if (status->flag & RX_FLAG_DECRYPTED)
2124                 return 0;
2125
2126         /* Drop unencrypted frames if key is set. */
2127         if (unlikely(!ieee80211_has_protected(fc) &&
2128                      !ieee80211_is_nullfunc(fc) &&
2129                      ieee80211_is_data(fc) && rx->key))
2130                 return -EACCES;
2131
2132         return 0;
2133 }
2134
2135 static int ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
2136 {
2137         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2138         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2139         __le16 fc = hdr->frame_control;
2140
2141         /*
2142          * Pass through unencrypted frames if the hardware has
2143          * decrypted them already.
2144          */
2145         if (status->flag & RX_FLAG_DECRYPTED)
2146                 return 0;
2147
2148         if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) {
2149                 if (unlikely(!ieee80211_has_protected(fc) &&
2150                              ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
2151                              rx->key)) {
2152                         if (ieee80211_is_deauth(fc) ||
2153                             ieee80211_is_disassoc(fc))
2154                                 cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
2155                                                              rx->skb->data,
2156                                                              rx->skb->len);
2157                         return -EACCES;
2158                 }
2159                 /* BIP does not use Protected field, so need to check MMIE */
2160                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
2161                              ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
2162                         if (ieee80211_is_deauth(fc) ||
2163                             ieee80211_is_disassoc(fc))
2164                                 cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
2165                                                              rx->skb->data,
2166                                                              rx->skb->len);
2167                         return -EACCES;
2168                 }
2169                 /*
2170                  * When using MFP, Action frames are not allowed prior to
2171                  * having configured keys.
2172                  */
2173                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
2174                              ieee80211_is_robust_mgmt_frame(rx->skb)))
2175                         return -EACCES;
2176         }
2177
2178         return 0;
2179 }
2180
2181 static int
2182 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx, bool *port_control)
2183 {
2184         struct ieee80211_sub_if_data *sdata = rx->sdata;
2185         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2186         bool check_port_control = false;
2187         struct ethhdr *ehdr;
2188         int ret;
2189
2190         *port_control = false;
2191         if (ieee80211_has_a4(hdr->frame_control) &&
2192             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
2193                 return -1;
2194
2195         if (sdata->vif.type == NL80211_IFTYPE_STATION &&
2196             !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) {
2197
2198                 if (!sdata->u.mgd.use_4addr)
2199                         return -1;
2200                 else
2201                         check_port_control = true;
2202         }
2203
2204         if (is_multicast_ether_addr(hdr->addr1) &&
2205             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta)
2206                 return -1;
2207
2208         ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
2209         if (ret < 0)
2210                 return ret;
2211
2212         ehdr = (struct ethhdr *) rx->skb->data;
2213         if (ehdr->h_proto == rx->sdata->control_port_protocol)
2214                 *port_control = true;
2215         else if (check_port_control)
2216                 return -1;
2217
2218         return 0;
2219 }
2220
2221 /*
2222  * requires that rx->skb is a frame with ethernet header
2223  */
2224 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
2225 {
2226         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
2227                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
2228         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
2229
2230         /*
2231          * Allow EAPOL frames to us/the PAE group address regardless
2232          * of whether the frame was encrypted or not.
2233          */
2234         if (ehdr->h_proto == rx->sdata->control_port_protocol &&
2235             (ether_addr_equal(ehdr->h_dest, rx->sdata->vif.addr) ||
2236              ether_addr_equal(ehdr->h_dest, pae_group_addr)))
2237                 return true;
2238
2239         if (ieee80211_802_1x_port_control(rx) ||
2240             ieee80211_drop_unencrypted(rx, fc))
2241                 return false;
2242
2243         return true;
2244 }
2245
2246 /*
2247  * requires that rx->skb is a frame with ethernet header
2248  */
2249 static void
2250 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
2251 {
2252         struct ieee80211_sub_if_data *sdata = rx->sdata;
2253         struct net_device *dev = sdata->dev;
2254         struct sk_buff *skb, *xmit_skb;
2255         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
2256         struct sta_info *dsta;
2257
2258         skb = rx->skb;
2259         xmit_skb = NULL;
2260
2261         ieee80211_rx_stats(dev, skb->len);
2262
2263         if (rx->sta) {
2264                 /* The seqno index has the same property as needed
2265                  * for the rx_msdu field, i.e. it is IEEE80211_NUM_TIDS
2266                  * for non-QoS-data frames. Here we know it's a data
2267                  * frame, so count MSDUs.
2268                  */
2269                 u64_stats_update_begin(&rx->sta->rx_stats.syncp);
2270                 rx->sta->rx_stats.msdu[rx->seqno_idx]++;
2271                 u64_stats_update_end(&rx->sta->rx_stats.syncp);
2272         }
2273
2274         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
2275              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
2276             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
2277             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
2278                 if (is_multicast_ether_addr(ehdr->h_dest) &&
2279                     ieee80211_vif_get_num_mcast_if(sdata) != 0) {
2280                         /*
2281                          * send multicast frames both to higher layers in
2282                          * local net stack and back to the wireless medium
2283                          */
2284                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
2285                         if (!xmit_skb)
2286                                 net_info_ratelimited("%s: failed to clone multicast frame\n",
2287                                                     dev->name);
2288                 } else if (!is_multicast_ether_addr(ehdr->h_dest)) {
2289                         dsta = sta_info_get(sdata, skb->data);
2290                         if (dsta) {
2291                                 /*
2292                                  * The destination station is associated to
2293                                  * this AP (in this VLAN), so send the frame
2294                                  * directly to it and do not pass it to local
2295                                  * net stack.
2296                                  */
2297                                 xmit_skb = skb;
2298                                 skb = NULL;
2299                         }
2300                 }
2301         }
2302
2303 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
2304         if (skb) {
2305                 /* 'align' will only take the values 0 or 2 here since all
2306                  * frames are required to be aligned to 2-byte boundaries
2307                  * when being passed to mac80211; the code here works just
2308                  * as well if that isn't true, but mac80211 assumes it can
2309                  * access fields as 2-byte aligned (e.g. for ether_addr_equal)
2310                  */
2311                 int align;
2312
2313                 align = (unsigned long)(skb->data + sizeof(struct ethhdr)) & 3;
2314                 if (align) {
2315                         if (WARN_ON(skb_headroom(skb) < 3)) {
2316                                 dev_kfree_skb(skb);
2317                                 skb = NULL;
2318                         } else {
2319                                 u8 *data = skb->data;
2320                                 size_t len = skb_headlen(skb);
2321                                 skb->data -= align;
2322                                 memmove(skb->data, data, len);
2323                                 skb_set_tail_pointer(skb, len);
2324                         }
2325                 }
2326         }
2327 #endif
2328
2329         if (skb) {
2330                 /* deliver to local stack */
2331                 skb->protocol = eth_type_trans(skb, dev);
2332                 memset(skb->cb, 0, sizeof(skb->cb));
2333                 if (rx->napi)
2334                         napi_gro_receive(rx->napi, skb);
2335                 else
2336                         netif_receive_skb(skb);
2337         }
2338
2339         if (xmit_skb) {
2340                 /*
2341                  * Send to wireless media and increase priority by 256 to
2342                  * keep the received priority instead of reclassifying
2343                  * the frame (see cfg80211_classify8021d).
2344                  */
2345                 xmit_skb->priority += 256;
2346                 xmit_skb->protocol = htons(ETH_P_802_3);
2347                 skb_reset_network_header(xmit_skb);
2348                 skb_reset_mac_header(xmit_skb);
2349                 dev_queue_xmit(xmit_skb);
2350         }
2351 }
2352
2353 static ieee80211_rx_result debug_noinline
2354 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
2355 {
2356         struct net_device *dev = rx->sdata->dev;
2357         struct sk_buff *skb = rx->skb;
2358         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2359         __le16 fc = hdr->frame_control;
2360         struct sk_buff_head frame_list;
2361         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2362         struct ethhdr ethhdr;
2363         const u8 *check_da = ethhdr.h_dest, *check_sa = ethhdr.h_source;
2364
2365         if (unlikely(!ieee80211_is_data(fc)))
2366                 return RX_CONTINUE;
2367
2368         if (unlikely(!ieee80211_is_data_present(fc)))
2369                 return RX_DROP_MONITOR;
2370
2371         if (!(status->rx_flags & IEEE80211_RX_AMSDU))
2372                 return RX_CONTINUE;
2373
2374         if (unlikely(ieee80211_has_a4(hdr->frame_control))) {
2375                 switch (rx->sdata->vif.type) {
2376                 case NL80211_IFTYPE_AP_VLAN:
2377                         if (!rx->sdata->u.vlan.sta)
2378                                 return RX_DROP_UNUSABLE;
2379                         break;
2380                 case NL80211_IFTYPE_STATION:
2381                         if (!rx->sdata->u.mgd.use_4addr)
2382                                 return RX_DROP_UNUSABLE;
2383                         break;
2384                 default:
2385                         return RX_DROP_UNUSABLE;
2386                 }
2387                 check_da = NULL;
2388                 check_sa = NULL;
2389         } else switch (rx->sdata->vif.type) {
2390                 case NL80211_IFTYPE_AP:
2391                 case NL80211_IFTYPE_AP_VLAN:
2392                         check_da = NULL;
2393                         break;
2394                 case NL80211_IFTYPE_STATION:
2395                         if (!rx->sta ||
2396                             !test_sta_flag(rx->sta, WLAN_STA_TDLS_PEER))
2397                                 check_sa = NULL;
2398                         break;
2399                 case NL80211_IFTYPE_MESH_POINT:
2400                         check_sa = NULL;
2401                         break;
2402                 default:
2403                         break;
2404         }
2405
2406         if (is_multicast_ether_addr(hdr->addr1))
2407                 return RX_DROP_UNUSABLE;
2408
2409         skb->dev = dev;
2410         __skb_queue_head_init(&frame_list);
2411
2412         if (ieee80211_data_to_8023_exthdr(skb, &ethhdr,
2413                                           rx->sdata->vif.addr,
2414                                           rx->sdata->vif.type))
2415                 return RX_DROP_UNUSABLE;
2416
2417         ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
2418                                  rx->sdata->vif.type,
2419                                  rx->local->hw.extra_tx_headroom,
2420                                  check_da, check_sa);
2421
2422         while (!skb_queue_empty(&frame_list)) {
2423                 rx->skb = __skb_dequeue(&frame_list);
2424
2425                 if (!ieee80211_frame_allowed(rx, fc)) {
2426                         dev_kfree_skb(rx->skb);
2427                         continue;
2428                 }
2429
2430                 ieee80211_deliver_skb(rx);
2431         }
2432
2433         return RX_QUEUED;
2434 }
2435
2436 #ifdef CONFIG_MAC80211_MESH
2437 static ieee80211_rx_result
2438 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
2439 {
2440         struct ieee80211_hdr *fwd_hdr, *hdr;
2441         struct ieee80211_tx_info *info;
2442         struct ieee80211s_hdr *mesh_hdr;
2443         struct sk_buff *skb = rx->skb, *fwd_skb;
2444         struct ieee80211_local *local = rx->local;
2445         struct ieee80211_sub_if_data *sdata = rx->sdata;
2446         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
2447         u16 ac, q, hdrlen;
2448
2449         hdr = (struct ieee80211_hdr *) skb->data;
2450         hdrlen = ieee80211_hdrlen(hdr->frame_control);
2451
2452         /* make sure fixed part of mesh header is there, also checks skb len */
2453         if (!pskb_may_pull(rx->skb, hdrlen + 6))
2454                 return RX_DROP_MONITOR;
2455
2456         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2457
2458         /* make sure full mesh header is there, also checks skb len */
2459         if (!pskb_may_pull(rx->skb,
2460                            hdrlen + ieee80211_get_mesh_hdrlen(mesh_hdr)))
2461                 return RX_DROP_MONITOR;
2462
2463         /* reload pointers */
2464         hdr = (struct ieee80211_hdr *) skb->data;
2465         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2466
2467         if (ieee80211_drop_unencrypted(rx, hdr->frame_control))
2468                 return RX_DROP_MONITOR;
2469
2470         /* frame is in RMC, don't forward */
2471         if (ieee80211_is_data(hdr->frame_control) &&
2472             is_multicast_ether_addr(hdr->addr1) &&
2473             mesh_rmc_check(rx->sdata, hdr->addr3, mesh_hdr))
2474                 return RX_DROP_MONITOR;
2475
2476         if (!ieee80211_is_data(hdr->frame_control))
2477                 return RX_CONTINUE;
2478
2479         if (!mesh_hdr->ttl)
2480                 return RX_DROP_MONITOR;
2481
2482         if (mesh_hdr->flags & MESH_FLAGS_AE) {
2483                 struct mesh_path *mppath;
2484                 char *proxied_addr;
2485                 char *mpp_addr;
2486
2487                 if (is_multicast_ether_addr(hdr->addr1)) {
2488                         mpp_addr = hdr->addr3;
2489                         proxied_addr = mesh_hdr->eaddr1;
2490                 } else if ((mesh_hdr->flags & MESH_FLAGS_AE) ==
2491                             MESH_FLAGS_AE_A5_A6) {
2492                         /* has_a4 already checked in ieee80211_rx_mesh_check */
2493                         mpp_addr = hdr->addr4;
2494                         proxied_addr = mesh_hdr->eaddr2;
2495                 } else {
2496                         return RX_DROP_MONITOR;
2497                 }
2498
2499                 rcu_read_lock();
2500                 mppath = mpp_path_lookup(sdata, proxied_addr);
2501                 if (!mppath) {
2502                         mpp_path_add(sdata, proxied_addr, mpp_addr);
2503                 } else {
2504                         spin_lock_bh(&mppath->state_lock);
2505                         if (!ether_addr_equal(mppath->mpp, mpp_addr))
2506                                 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
2507                         mppath->exp_time = jiffies;
2508                         spin_unlock_bh(&mppath->state_lock);
2509                 }
2510                 rcu_read_unlock();
2511         }
2512
2513         /* Frame has reached destination.  Don't forward */
2514         if (!is_multicast_ether_addr(hdr->addr1) &&
2515             ether_addr_equal(sdata->vif.addr, hdr->addr3))
2516                 return RX_CONTINUE;
2517
2518         ac = ieee80211_select_queue_80211(sdata, skb, hdr);
2519         q = sdata->vif.hw_queue[ac];
2520         if (ieee80211_queue_stopped(&local->hw, q)) {
2521                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion);
2522                 return RX_DROP_MONITOR;
2523         }
2524         skb_set_queue_mapping(skb, q);
2525
2526         if (!--mesh_hdr->ttl) {
2527                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
2528                 goto out;
2529         }
2530
2531         if (!ifmsh->mshcfg.dot11MeshForwarding)
2532                 goto out;
2533
2534         fwd_skb = skb_copy_expand(skb, local->tx_headroom +
2535                                        sdata->encrypt_headroom, 0, GFP_ATOMIC);
2536         if (!fwd_skb) {
2537                 net_info_ratelimited("%s: failed to clone mesh frame\n",
2538                                     sdata->name);
2539                 goto out;
2540         }
2541
2542         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
2543         fwd_hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_RETRY);
2544         info = IEEE80211_SKB_CB(fwd_skb);
2545         memset(info, 0, sizeof(*info));
2546         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
2547         info->control.vif = &rx->sdata->vif;
2548         info->control.jiffies = jiffies;
2549         if (is_multicast_ether_addr(fwd_hdr->addr1)) {
2550                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_mcast);
2551                 memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
2552                 /* update power mode indication when forwarding */
2553                 ieee80211_mps_set_frame_flags(sdata, NULL, fwd_hdr);
2554         } else if (!mesh_nexthop_lookup(sdata, fwd_skb)) {
2555                 /* mesh power mode flags updated in mesh_nexthop_lookup */
2556                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_unicast);
2557         } else {
2558                 /* unable to resolve next hop */
2559                 mesh_path_error_tx(sdata, ifmsh->mshcfg.element_ttl,
2560                                    fwd_hdr->addr3, 0,
2561                                    WLAN_REASON_MESH_PATH_NOFORWARD,
2562                                    fwd_hdr->addr2);
2563                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_no_route);
2564                 kfree_skb(fwd_skb);
2565                 return RX_DROP_MONITOR;
2566         }
2567
2568         IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_frames);
2569         ieee80211_add_pending_skb(local, fwd_skb);
2570  out:
2571         if (is_multicast_ether_addr(hdr->addr1))
2572                 return RX_CONTINUE;
2573         return RX_DROP_MONITOR;
2574 }
2575 #endif
2576
2577 static ieee80211_rx_result debug_noinline
2578 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
2579 {
2580         struct ieee80211_sub_if_data *sdata = rx->sdata;
2581         struct ieee80211_local *local = rx->local;
2582         struct net_device *dev = sdata->dev;
2583         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2584         __le16 fc = hdr->frame_control;
2585         bool port_control;
2586         int err;
2587
2588         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
2589                 return RX_CONTINUE;
2590
2591         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
2592                 return RX_DROP_MONITOR;
2593
2594         /*
2595          * Send unexpected-4addr-frame event to hostapd. For older versions,
2596          * also drop the frame to cooked monitor interfaces.
2597          */
2598         if (ieee80211_has_a4(hdr->frame_control) &&
2599             sdata->vif.type == NL80211_IFTYPE_AP) {
2600                 if (rx->sta &&
2601                     !test_and_set_sta_flag(rx->sta, WLAN_STA_4ADDR_EVENT))
2602                         cfg80211_rx_unexpected_4addr_frame(
2603                                 rx->sdata->dev, rx->sta->sta.addr, GFP_ATOMIC);
2604                 return RX_DROP_MONITOR;
2605         }
2606
2607         err = __ieee80211_data_to_8023(rx, &port_control);
2608         if (unlikely(err))
2609                 return RX_DROP_UNUSABLE;
2610
2611         if (!ieee80211_frame_allowed(rx, fc))
2612                 return RX_DROP_MONITOR;
2613
2614         /* directly handle TDLS channel switch requests/responses */
2615         if (unlikely(((struct ethhdr *)rx->skb->data)->h_proto ==
2616                                                 cpu_to_be16(ETH_P_TDLS))) {
2617                 struct ieee80211_tdls_data *tf = (void *)rx->skb->data;
2618
2619                 if (pskb_may_pull(rx->skb,
2620                                   offsetof(struct ieee80211_tdls_data, u)) &&
2621                     tf->payload_type == WLAN_TDLS_SNAP_RFTYPE &&
2622                     tf->category == WLAN_CATEGORY_TDLS &&
2623                     (tf->action_code == WLAN_TDLS_CHANNEL_SWITCH_REQUEST ||
2624                      tf->action_code == WLAN_TDLS_CHANNEL_SWITCH_RESPONSE)) {
2625                         skb_queue_tail(&local->skb_queue_tdls_chsw, rx->skb);
2626                         schedule_work(&local->tdls_chsw_work);
2627                         if (rx->sta)
2628                                 rx->sta->rx_stats.packets++;
2629
2630                         return RX_QUEUED;
2631                 }
2632         }
2633
2634         if (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
2635             unlikely(port_control) && sdata->bss) {
2636                 sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
2637                                      u.ap);
2638                 dev = sdata->dev;
2639                 rx->sdata = sdata;
2640         }
2641
2642         rx->skb->dev = dev;
2643
2644         if (!ieee80211_hw_check(&local->hw, SUPPORTS_DYNAMIC_PS) &&
2645             local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
2646             !is_multicast_ether_addr(
2647                     ((struct ethhdr *)rx->skb->data)->h_dest) &&
2648             (!local->scanning &&
2649              !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state)))
2650                 mod_timer(&local->dynamic_ps_timer, jiffies +
2651                           msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
2652
2653         ieee80211_deliver_skb(rx);
2654
2655         return RX_QUEUED;
2656 }
2657
2658 static ieee80211_rx_result debug_noinline
2659 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
2660 {
2661         struct sk_buff *skb = rx->skb;
2662         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
2663         struct tid_ampdu_rx *tid_agg_rx;
2664         u16 start_seq_num;
2665         u16 tid;
2666
2667         if (likely(!ieee80211_is_ctl(bar->frame_control)))
2668                 return RX_CONTINUE;
2669
2670         if (ieee80211_is_back_req(bar->frame_control)) {
2671                 struct {
2672                         __le16 control, start_seq_num;
2673                 } __packed bar_data;
2674                 struct ieee80211_event event = {
2675                         .type = BAR_RX_EVENT,
2676                 };
2677
2678                 if (!rx->sta)
2679                         return RX_DROP_MONITOR;
2680
2681                 if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
2682                                   &bar_data, sizeof(bar_data)))
2683                         return RX_DROP_MONITOR;
2684
2685                 tid = le16_to_cpu(bar_data.control) >> 12;
2686
2687                 if (!test_bit(tid, rx->sta->ampdu_mlme.agg_session_valid) &&
2688                     !test_and_set_bit(tid, rx->sta->ampdu_mlme.unexpected_agg))
2689                         ieee80211_send_delba(rx->sdata, rx->sta->sta.addr, tid,
2690                                              WLAN_BACK_RECIPIENT,
2691                                              WLAN_REASON_QSTA_REQUIRE_SETUP);
2692
2693                 tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
2694                 if (!tid_agg_rx)
2695                         return RX_DROP_MONITOR;
2696
2697                 start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
2698                 event.u.ba.tid = tid;
2699                 event.u.ba.ssn = start_seq_num;
2700                 event.u.ba.sta = &rx->sta->sta;
2701
2702                 /* reset session timer */
2703                 if (tid_agg_rx->timeout)
2704                         mod_timer(&tid_agg_rx->session_timer,
2705                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
2706
2707                 spin_lock(&tid_agg_rx->reorder_lock);
2708                 /* release stored frames up to start of BAR */
2709                 ieee80211_release_reorder_frames(rx->sdata, tid_agg_rx,
2710                                                  start_seq_num, frames);
2711                 spin_unlock(&tid_agg_rx->reorder_lock);
2712
2713                 drv_event_callback(rx->local, rx->sdata, &event);
2714
2715                 kfree_skb(skb);
2716                 return RX_QUEUED;
2717         }
2718
2719         /*
2720          * After this point, we only want management frames,
2721          * so we can drop all remaining control frames to
2722          * cooked monitor interfaces.
2723          */
2724         return RX_DROP_MONITOR;
2725 }
2726
2727 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
2728                                            struct ieee80211_mgmt *mgmt,
2729                                            size_t len)
2730 {
2731         struct ieee80211_local *local = sdata->local;
2732         struct sk_buff *skb;
2733         struct ieee80211_mgmt *resp;
2734
2735         if (!ether_addr_equal(mgmt->da, sdata->vif.addr)) {
2736                 /* Not to own unicast address */
2737                 return;
2738         }
2739
2740         if (!ether_addr_equal(mgmt->sa, sdata->u.mgd.bssid) ||
2741             !ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid)) {
2742                 /* Not from the current AP or not associated yet. */
2743                 return;
2744         }
2745
2746         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
2747                 /* Too short SA Query request frame */
2748                 return;
2749         }
2750
2751         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
2752         if (skb == NULL)
2753                 return;
2754
2755         skb_reserve(skb, local->hw.extra_tx_headroom);
2756         resp = skb_put_zero(skb, 24);
2757         memcpy(resp->da, mgmt->sa, ETH_ALEN);
2758         memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
2759         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
2760         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2761                                           IEEE80211_STYPE_ACTION);
2762         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
2763         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
2764         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
2765         memcpy(resp->u.action.u.sa_query.trans_id,
2766                mgmt->u.action.u.sa_query.trans_id,
2767                WLAN_SA_QUERY_TR_ID_LEN);
2768
2769         ieee80211_tx_skb(sdata, skb);
2770 }
2771
2772 static ieee80211_rx_result debug_noinline
2773 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
2774 {
2775         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2776         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2777
2778         /*
2779          * From here on, look only at management frames.
2780          * Data and control frames are already handled,
2781          * and unknown (reserved) frames are useless.
2782          */
2783         if (rx->skb->len < 24)
2784                 return RX_DROP_MONITOR;
2785
2786         if (!ieee80211_is_mgmt(mgmt->frame_control))
2787                 return RX_DROP_MONITOR;
2788
2789         if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
2790             ieee80211_is_beacon(mgmt->frame_control) &&
2791             !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) {
2792                 int sig = 0;
2793
2794                 if (ieee80211_hw_check(&rx->local->hw, SIGNAL_DBM))
2795                         sig = status->signal;
2796
2797                 cfg80211_report_obss_beacon(rx->local->hw.wiphy,
2798                                             rx->skb->data, rx->skb->len,
2799                                             status->freq, sig);
2800                 rx->flags |= IEEE80211_RX_BEACON_REPORTED;
2801         }
2802
2803         if (ieee80211_drop_unencrypted_mgmt(rx))
2804                 return RX_DROP_UNUSABLE;
2805
2806         return RX_CONTINUE;
2807 }
2808
2809 static ieee80211_rx_result debug_noinline
2810 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2811 {
2812         struct ieee80211_local *local = rx->local;
2813         struct ieee80211_sub_if_data *sdata = rx->sdata;
2814         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2815         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2816         int len = rx->skb->len;
2817
2818         if (!ieee80211_is_action(mgmt->frame_control))
2819                 return RX_CONTINUE;
2820
2821         /* drop too small frames */
2822         if (len < IEEE80211_MIN_ACTION_SIZE)
2823                 return RX_DROP_UNUSABLE;
2824
2825         if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC &&
2826             mgmt->u.action.category != WLAN_CATEGORY_SELF_PROTECTED &&
2827             mgmt->u.action.category != WLAN_CATEGORY_SPECTRUM_MGMT)
2828                 return RX_DROP_UNUSABLE;
2829
2830         switch (mgmt->u.action.category) {
2831         case WLAN_CATEGORY_HT:
2832                 /* reject HT action frames from stations not supporting HT */
2833                 if (!rx->sta->sta.ht_cap.ht_supported)
2834                         goto invalid;
2835
2836                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2837                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2838                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2839                     sdata->vif.type != NL80211_IFTYPE_AP &&
2840                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2841                         break;
2842
2843                 /* verify action & smps_control/chanwidth are present */
2844                 if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2845                         goto invalid;
2846
2847                 switch (mgmt->u.action.u.ht_smps.action) {
2848                 case WLAN_HT_ACTION_SMPS: {
2849                         struct ieee80211_supported_band *sband;
2850                         enum ieee80211_smps_mode smps_mode;
2851
2852                         /* convert to HT capability */
2853                         switch (mgmt->u.action.u.ht_smps.smps_control) {
2854                         case WLAN_HT_SMPS_CONTROL_DISABLED:
2855                                 smps_mode = IEEE80211_SMPS_OFF;
2856                                 break;
2857                         case WLAN_HT_SMPS_CONTROL_STATIC:
2858                                 smps_mode = IEEE80211_SMPS_STATIC;
2859                                 break;
2860                         case WLAN_HT_SMPS_CONTROL_DYNAMIC:
2861                                 smps_mode = IEEE80211_SMPS_DYNAMIC;
2862                                 break;
2863                         default:
2864                                 goto invalid;
2865                         }
2866
2867                         /* if no change do nothing */
2868                         if (rx->sta->sta.smps_mode == smps_mode)
2869                                 goto handled;
2870                         rx->sta->sta.smps_mode = smps_mode;
2871
2872                         sband = rx->local->hw.wiphy->bands[status->band];
2873
2874                         rate_control_rate_update(local, sband, rx->sta,
2875                                                  IEEE80211_RC_SMPS_CHANGED);
2876                         goto handled;
2877                 }
2878                 case WLAN_HT_ACTION_NOTIFY_CHANWIDTH: {
2879                         struct ieee80211_supported_band *sband;
2880                         u8 chanwidth = mgmt->u.action.u.ht_notify_cw.chanwidth;
2881                         enum ieee80211_sta_rx_bandwidth max_bw, new_bw;
2882
2883                         /* If it doesn't support 40 MHz it can't change ... */
2884                         if (!(rx->sta->sta.ht_cap.cap &
2885                                         IEEE80211_HT_CAP_SUP_WIDTH_20_40))
2886                                 goto handled;
2887
2888                         if (chanwidth == IEEE80211_HT_CHANWIDTH_20MHZ)
2889                                 max_bw = IEEE80211_STA_RX_BW_20;
2890                         else
2891                                 max_bw = ieee80211_sta_cap_rx_bw(rx->sta);
2892
2893                         /* set cur_max_bandwidth and recalc sta bw */
2894                         rx->sta->cur_max_bandwidth = max_bw;
2895                         new_bw = ieee80211_sta_cur_vht_bw(rx->sta);
2896
2897                         if (rx->sta->sta.bandwidth == new_bw)
2898                                 goto handled;
2899
2900                         rx->sta->sta.bandwidth = new_bw;
2901                         sband = rx->local->hw.wiphy->bands[status->band];
2902
2903                         rate_control_rate_update(local, sband, rx->sta,
2904                                                  IEEE80211_RC_BW_CHANGED);
2905                         goto handled;
2906                 }
2907                 default:
2908                         goto invalid;
2909                 }
2910
2911                 break;
2912         case WLAN_CATEGORY_PUBLIC:
2913                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2914                         goto invalid;
2915                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2916                         break;
2917                 if (!rx->sta)
2918                         break;
2919                 if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
2920                         break;
2921                 if (mgmt->u.action.u.ext_chan_switch.action_code !=
2922                                 WLAN_PUB_ACTION_EXT_CHANSW_ANN)
2923                         break;
2924                 if (len < offsetof(struct ieee80211_mgmt,
2925                                    u.action.u.ext_chan_switch.variable))
2926                         goto invalid;
2927                 goto queue;
2928         case WLAN_CATEGORY_VHT:
2929                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2930                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2931                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2932                     sdata->vif.type != NL80211_IFTYPE_AP &&
2933                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2934                         break;
2935
2936                 /* verify action code is present */
2937                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2938                         goto invalid;
2939
2940                 switch (mgmt->u.action.u.vht_opmode_notif.action_code) {
2941                 case WLAN_VHT_ACTION_OPMODE_NOTIF: {
2942                         /* verify opmode is present */
2943                         if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2944                                 goto invalid;
2945                         goto queue;
2946                 }
2947                 case WLAN_VHT_ACTION_GROUPID_MGMT: {
2948                         if (len < IEEE80211_MIN_ACTION_SIZE + 25)
2949                                 goto invalid;
2950                         goto queue;
2951                 }
2952                 default:
2953                         break;
2954                 }
2955                 break;
2956         case WLAN_CATEGORY_BACK:
2957                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2958                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2959                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2960                     sdata->vif.type != NL80211_IFTYPE_AP &&
2961                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2962                         break;
2963
2964                 /* verify action_code is present */
2965                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2966                         break;
2967
2968                 switch (mgmt->u.action.u.addba_req.action_code) {
2969                 case WLAN_ACTION_ADDBA_REQ:
2970                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2971                                    sizeof(mgmt->u.action.u.addba_req)))
2972                                 goto invalid;
2973                         break;
2974                 case WLAN_ACTION_ADDBA_RESP:
2975                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2976                                    sizeof(mgmt->u.action.u.addba_resp)))
2977                                 goto invalid;
2978                         break;
2979                 case WLAN_ACTION_DELBA:
2980                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2981                                    sizeof(mgmt->u.action.u.delba)))
2982                                 goto invalid;
2983                         break;
2984                 default:
2985                         goto invalid;
2986                 }
2987
2988                 goto queue;
2989         case WLAN_CATEGORY_SPECTRUM_MGMT:
2990                 /* verify action_code is present */
2991                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2992                         break;
2993
2994                 switch (mgmt->u.action.u.measurement.action_code) {
2995                 case WLAN_ACTION_SPCT_MSR_REQ:
2996                         if (status->band != NL80211_BAND_5GHZ)
2997                                 break;
2998
2999                         if (len < (IEEE80211_MIN_ACTION_SIZE +
3000                                    sizeof(mgmt->u.action.u.measurement)))
3001                                 break;
3002
3003                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
3004                                 break;
3005
3006                         ieee80211_process_measurement_req(sdata, mgmt, len);
3007                         goto handled;
3008                 case WLAN_ACTION_SPCT_CHL_SWITCH: {
3009                         u8 *bssid;
3010                         if (len < (IEEE80211_MIN_ACTION_SIZE +
3011                                    sizeof(mgmt->u.action.u.chan_switch)))
3012                                 break;
3013
3014                         if (sdata->vif.type != NL80211_IFTYPE_STATION &&
3015                             sdata->vif.type != NL80211_IFTYPE_ADHOC &&
3016                             sdata->vif.type != NL80211_IFTYPE_MESH_POINT)
3017                                 break;
3018
3019                         if (sdata->vif.type == NL80211_IFTYPE_STATION)
3020                                 bssid = sdata->u.mgd.bssid;
3021                         else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
3022                                 bssid = sdata->u.ibss.bssid;
3023                         else if (sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
3024                                 bssid = mgmt->sa;
3025                         else
3026                                 break;
3027
3028                         if (!ether_addr_equal(mgmt->bssid, bssid))
3029                                 break;
3030
3031                         goto queue;
3032                         }
3033                 }
3034                 break;
3035         case WLAN_CATEGORY_SA_QUERY:
3036                 if (len < (IEEE80211_MIN_ACTION_SIZE +
3037                            sizeof(mgmt->u.action.u.sa_query)))
3038                         break;
3039
3040                 switch (mgmt->u.action.u.sa_query.action) {
3041                 case WLAN_ACTION_SA_QUERY_REQUEST:
3042                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
3043                                 break;
3044                         ieee80211_process_sa_query_req(sdata, mgmt, len);
3045                         goto handled;
3046                 }
3047                 break;
3048         case WLAN_CATEGORY_SELF_PROTECTED:
3049                 if (len < (IEEE80211_MIN_ACTION_SIZE +
3050                            sizeof(mgmt->u.action.u.self_prot.action_code)))
3051                         break;
3052
3053                 switch (mgmt->u.action.u.self_prot.action_code) {
3054                 case WLAN_SP_MESH_PEERING_OPEN:
3055                 case WLAN_SP_MESH_PEERING_CLOSE:
3056                 case WLAN_SP_MESH_PEERING_CONFIRM:
3057                         if (!ieee80211_vif_is_mesh(&sdata->vif))
3058                                 goto invalid;
3059                         if (sdata->u.mesh.user_mpm)
3060                                 /* userspace handles this frame */
3061                                 break;
3062                         goto queue;
3063                 case WLAN_SP_MGK_INFORM:
3064                 case WLAN_SP_MGK_ACK:
3065                         if (!ieee80211_vif_is_mesh(&sdata->vif))
3066                                 goto invalid;
3067                         break;
3068                 }
3069                 break;
3070         case WLAN_CATEGORY_MESH_ACTION:
3071                 if (len < (IEEE80211_MIN_ACTION_SIZE +
3072                            sizeof(mgmt->u.action.u.mesh_action.action_code)))
3073                         break;
3074
3075                 if (!ieee80211_vif_is_mesh(&sdata->vif))
3076                         break;
3077                 if (mesh_action_is_path_sel(mgmt) &&
3078                     !mesh_path_sel_is_hwmp(sdata))
3079                         break;
3080                 goto queue;
3081         }
3082
3083         return RX_CONTINUE;
3084
3085  invalid:
3086         status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
3087         /* will return in the next handlers */
3088         return RX_CONTINUE;
3089
3090  handled:
3091         if (rx->sta)
3092                 rx->sta->rx_stats.packets++;
3093         dev_kfree_skb(rx->skb);
3094         return RX_QUEUED;
3095
3096  queue:
3097         skb_queue_tail(&sdata->skb_queue, rx->skb);
3098         ieee80211_queue_work(&local->hw, &sdata->work);
3099         if (rx->sta)
3100                 rx->sta->rx_stats.packets++;
3101         return RX_QUEUED;
3102 }
3103
3104 static ieee80211_rx_result debug_noinline
3105 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
3106 {
3107         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
3108         int sig = 0;
3109
3110         /* skip known-bad action frames and return them in the next handler */
3111         if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
3112                 return RX_CONTINUE;
3113
3114         /*
3115          * Getting here means the kernel doesn't know how to handle
3116          * it, but maybe userspace does ... include returned frames
3117          * so userspace can register for those to know whether ones
3118          * it transmitted were processed or returned.
3119          */
3120
3121         if (ieee80211_hw_check(&rx->local->hw, SIGNAL_DBM))
3122                 sig = status->signal;
3123
3124         if (cfg80211_rx_mgmt(&rx->sdata->wdev, status->freq, sig,
3125                              rx->skb->data, rx->skb->len, 0)) {
3126                 if (rx->sta)
3127                         rx->sta->rx_stats.packets++;
3128                 dev_kfree_skb(rx->skb);
3129                 return RX_QUEUED;
3130         }
3131
3132         return RX_CONTINUE;
3133 }
3134
3135 static ieee80211_rx_result debug_noinline
3136 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
3137 {
3138         struct ieee80211_local *local = rx->local;
3139         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
3140         struct sk_buff *nskb;
3141         struct ieee80211_sub_if_data *sdata = rx->sdata;
3142         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
3143
3144         if (!ieee80211_is_action(mgmt->frame_control))
3145                 return RX_CONTINUE;
3146
3147         /*
3148          * For AP mode, hostapd is responsible for handling any action
3149          * frames that we didn't handle, including returning unknown
3150          * ones. For all other modes we will return them to the sender,
3151          * setting the 0x80 bit in the action category, as required by
3152          * 802.11-2012 9.24.4.
3153          * Newer versions of hostapd shall also use the management frame
3154          * registration mechanisms, but older ones still use cooked
3155          * monitor interfaces so push all frames there.
3156          */
3157         if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
3158             (sdata->vif.type == NL80211_IFTYPE_AP ||
3159              sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
3160                 return RX_DROP_MONITOR;
3161
3162         if (is_multicast_ether_addr(mgmt->da))
3163                 return RX_DROP_MONITOR;
3164
3165         /* do not return rejected action frames */
3166         if (mgmt->u.action.category & 0x80)
3167                 return RX_DROP_UNUSABLE;
3168
3169         nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
3170                                GFP_ATOMIC);
3171         if (nskb) {
3172                 struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
3173
3174                 nmgmt->u.action.category |= 0x80;
3175                 memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
3176                 memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
3177
3178                 memset(nskb->cb, 0, sizeof(nskb->cb));
3179
3180                 if (rx->sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE) {
3181                         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(nskb);
3182
3183                         info->flags = IEEE80211_TX_CTL_TX_OFFCHAN |
3184                                       IEEE80211_TX_INTFL_OFFCHAN_TX_OK |
3185                                       IEEE80211_TX_CTL_NO_CCK_RATE;
3186                         if (ieee80211_hw_check(&local->hw, QUEUE_CONTROL))
3187                                 info->hw_queue =
3188                                         local->hw.offchannel_tx_hw_queue;
3189                 }
3190
3191                 __ieee80211_tx_skb_tid_band(rx->sdata, nskb, 7,
3192                                             status->band);
3193         }
3194         dev_kfree_skb(rx->skb);
3195         return RX_QUEUED;
3196 }
3197
3198 static ieee80211_rx_result debug_noinline
3199 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
3200 {
3201         struct ieee80211_sub_if_data *sdata = rx->sdata;
3202         struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
3203         __le16 stype;
3204
3205         stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
3206
3207         if (!ieee80211_vif_is_mesh(&sdata->vif) &&
3208             sdata->vif.type != NL80211_IFTYPE_ADHOC &&
3209             sdata->vif.type != NL80211_IFTYPE_OCB &&
3210             sdata->vif.type != NL80211_IFTYPE_STATION)
3211                 return RX_DROP_MONITOR;
3212
3213         switch (stype) {
3214         case cpu_to_le16(IEEE80211_STYPE_AUTH):
3215         case cpu_to_le16(IEEE80211_STYPE_BEACON):
3216         case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
3217                 /* process for all: mesh, mlme, ibss */
3218                 break;
3219         case cpu_to_le16(IEEE80211_STYPE_ASSOC_RESP):
3220         case cpu_to_le16(IEEE80211_STYPE_REASSOC_RESP):
3221         case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
3222         case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
3223                 if (is_multicast_ether_addr(mgmt->da) &&
3224                     !is_broadcast_ether_addr(mgmt->da))
3225                         return RX_DROP_MONITOR;
3226
3227                 /* process only for station */
3228                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
3229                         return RX_DROP_MONITOR;
3230                 break;
3231         case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
3232                 /* process only for ibss and mesh */
3233                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC &&
3234                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT)
3235                         return RX_DROP_MONITOR;
3236                 break;
3237         default:
3238                 return RX_DROP_MONITOR;
3239         }
3240
3241         /* queue up frame and kick off work to process it */
3242         skb_queue_tail(&sdata->skb_queue, rx->skb);
3243         ieee80211_queue_work(&rx->local->hw, &sdata->work);
3244         if (rx->sta)
3245                 rx->sta->rx_stats.packets++;
3246
3247         return RX_QUEUED;
3248 }
3249
3250 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
3251                                         struct ieee80211_rate *rate)
3252 {
3253         struct ieee80211_sub_if_data *sdata;
3254         struct ieee80211_local *local = rx->local;
3255         struct sk_buff *skb = rx->skb, *skb2;
3256         struct net_device *prev_dev = NULL;
3257         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3258         int needed_headroom;
3259
3260         /*
3261          * If cooked monitor has been processed already, then
3262          * don't do it again. If not, set the flag.
3263          */
3264         if (rx->flags & IEEE80211_RX_CMNTR)
3265                 goto out_free_skb;
3266         rx->flags |= IEEE80211_RX_CMNTR;
3267
3268         /* If there are no cooked monitor interfaces, just free the SKB */
3269         if (!local->cooked_mntrs)
3270                 goto out_free_skb;
3271
3272         /* vendor data is long removed here */
3273         status->flag &= ~RX_FLAG_RADIOTAP_VENDOR_DATA;
3274         /* room for the radiotap header based on driver features */
3275         needed_headroom = ieee80211_rx_radiotap_hdrlen(local, status, skb);
3276
3277         if (skb_headroom(skb) < needed_headroom &&
3278             pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC))
3279                 goto out_free_skb;
3280
3281         /* prepend radiotap information */
3282         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
3283                                          false);
3284
3285         skb_reset_mac_header(skb);
3286         skb->ip_summed = CHECKSUM_UNNECESSARY;
3287         skb->pkt_type = PACKET_OTHERHOST;
3288         skb->protocol = htons(ETH_P_802_2);
3289
3290         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
3291                 if (!ieee80211_sdata_running(sdata))
3292                         continue;
3293
3294                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
3295                     !(sdata->u.mntr.flags & MONITOR_FLAG_COOK_FRAMES))
3296                         continue;
3297
3298                 if (prev_dev) {
3299                         skb2 = skb_clone(skb, GFP_ATOMIC);
3300                         if (skb2) {
3301                                 skb2->dev = prev_dev;
3302                                 netif_receive_skb(skb2);
3303                         }
3304                 }
3305
3306                 prev_dev = sdata->dev;
3307                 ieee80211_rx_stats(sdata->dev, skb->len);
3308         }
3309
3310         if (prev_dev) {
3311                 skb->dev = prev_dev;
3312                 netif_receive_skb(skb);
3313                 return;
3314         }
3315
3316  out_free_skb:
3317         dev_kfree_skb(skb);
3318 }
3319
3320 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
3321                                          ieee80211_rx_result res)
3322 {
3323         switch (res) {
3324         case RX_DROP_MONITOR:
3325                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
3326                 if (rx->sta)
3327                         rx->sta->rx_stats.dropped++;
3328                 /* fall through */
3329         case RX_CONTINUE: {
3330                 struct ieee80211_rate *rate = NULL;
3331                 struct ieee80211_supported_band *sband;
3332                 struct ieee80211_rx_status *status;
3333
3334                 status = IEEE80211_SKB_RXCB((rx->skb));
3335
3336                 sband = rx->local->hw.wiphy->bands[status->band];
3337                 if (!(status->encoding == RX_ENC_HT) &&
3338                     !(status->encoding == RX_ENC_VHT))
3339                         rate = &sband->bitrates[status->rate_idx];
3340
3341                 ieee80211_rx_cooked_monitor(rx, rate);
3342                 break;
3343                 }
3344         case RX_DROP_UNUSABLE:
3345                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
3346                 if (rx->sta)
3347                         rx->sta->rx_stats.dropped++;
3348                 dev_kfree_skb(rx->skb);
3349                 break;
3350         case RX_QUEUED:
3351                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
3352                 break;
3353         }
3354 }
3355
3356 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
3357                                   struct sk_buff_head *frames)
3358 {
3359         ieee80211_rx_result res = RX_DROP_MONITOR;
3360         struct sk_buff *skb;
3361
3362 #define CALL_RXH(rxh)                   \
3363         do {                            \
3364                 res = rxh(rx);          \
3365                 if (res != RX_CONTINUE) \
3366                         goto rxh_next;  \
3367         } while (0)
3368
3369         /* Lock here to avoid hitting all of the data used in the RX
3370          * path (e.g. key data, station data, ...) concurrently when
3371          * a frame is released from the reorder buffer due to timeout
3372          * from the timer, potentially concurrently with RX from the
3373          * driver.
3374          */
3375         spin_lock_bh(&rx->local->rx_path_lock);
3376
3377         while ((skb = __skb_dequeue(frames))) {
3378                 /*
3379                  * all the other fields are valid across frames
3380                  * that belong to an aMPDU since they are on the
3381                  * same TID from the same station
3382                  */
3383                 rx->skb = skb;
3384
3385                 CALL_RXH(ieee80211_rx_h_check_more_data);
3386                 CALL_RXH(ieee80211_rx_h_uapsd_and_pspoll);
3387                 CALL_RXH(ieee80211_rx_h_sta_process);
3388                 CALL_RXH(ieee80211_rx_h_decrypt);
3389                 CALL_RXH(ieee80211_rx_h_defragment);
3390                 CALL_RXH(ieee80211_rx_h_michael_mic_verify);
3391                 /* must be after MMIC verify so header is counted in MPDU mic */
3392 #ifdef CONFIG_MAC80211_MESH
3393                 if (ieee80211_vif_is_mesh(&rx->sdata->vif))
3394                         CALL_RXH(ieee80211_rx_h_mesh_fwding);
3395 #endif
3396                 CALL_RXH(ieee80211_rx_h_amsdu);
3397                 CALL_RXH(ieee80211_rx_h_data);
3398
3399                 /* special treatment -- needs the queue */
3400                 res = ieee80211_rx_h_ctrl(rx, frames);
3401                 if (res != RX_CONTINUE)
3402                         goto rxh_next;
3403
3404                 CALL_RXH(ieee80211_rx_h_mgmt_check);
3405                 CALL_RXH(ieee80211_rx_h_action);
3406                 CALL_RXH(ieee80211_rx_h_userspace_mgmt);
3407                 CALL_RXH(ieee80211_rx_h_action_return);
3408                 CALL_RXH(ieee80211_rx_h_mgmt);
3409
3410  rxh_next:
3411                 ieee80211_rx_handlers_result(rx, res);
3412
3413 #undef CALL_RXH
3414         }
3415
3416         spin_unlock_bh(&rx->local->rx_path_lock);
3417 }
3418
3419 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
3420 {
3421         struct sk_buff_head reorder_release;
3422         ieee80211_rx_result res = RX_DROP_MONITOR;
3423
3424         __skb_queue_head_init(&reorder_release);
3425
3426 #define CALL_RXH(rxh)                   \
3427         do {                            \
3428                 res = rxh(rx);          \
3429                 if (res != RX_CONTINUE) \
3430                         goto rxh_next;  \
3431         } while (0)
3432
3433         CALL_RXH(ieee80211_rx_h_check_dup);
3434         CALL_RXH(ieee80211_rx_h_check);
3435
3436         ieee80211_rx_reorder_ampdu(rx, &reorder_release);
3437
3438         ieee80211_rx_handlers(rx, &reorder_release);
3439         return;
3440
3441  rxh_next:
3442         ieee80211_rx_handlers_result(rx, res);
3443
3444 #undef CALL_RXH
3445 }
3446
3447 /*
3448  * This function makes calls into the RX path, therefore
3449  * it has to be invoked under RCU read lock.
3450  */
3451 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
3452 {
3453         struct sk_buff_head frames;
3454         struct ieee80211_rx_data rx = {
3455                 .sta = sta,
3456                 .sdata = sta->sdata,
3457                 .local = sta->local,
3458                 /* This is OK -- must be QoS data frame */
3459                 .security_idx = tid,
3460                 .seqno_idx = tid,
3461                 .napi = NULL, /* must be NULL to not have races */
3462         };
3463         struct tid_ampdu_rx *tid_agg_rx;
3464
3465         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
3466         if (!tid_agg_rx)
3467                 return;
3468
3469         __skb_queue_head_init(&frames);
3470
3471         spin_lock(&tid_agg_rx->reorder_lock);
3472         ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx, &frames);
3473         spin_unlock(&tid_agg_rx->reorder_lock);
3474
3475         if (!skb_queue_empty(&frames)) {
3476                 struct ieee80211_event event = {
3477                         .type = BA_FRAME_TIMEOUT,
3478                         .u.ba.tid = tid,
3479                         .u.ba.sta = &sta->sta,
3480                 };
3481                 drv_event_callback(rx.local, rx.sdata, &event);
3482         }
3483
3484         ieee80211_rx_handlers(&rx, &frames);
3485 }
3486
3487 void ieee80211_mark_rx_ba_filtered_frames(struct ieee80211_sta *pubsta, u8 tid,
3488                                           u16 ssn, u64 filtered,
3489                                           u16 received_mpdus)
3490 {
3491         struct sta_info *sta;
3492         struct tid_ampdu_rx *tid_agg_rx;
3493         struct sk_buff_head frames;
3494         struct ieee80211_rx_data rx = {
3495                 /* This is OK -- must be QoS data frame */
3496                 .security_idx = tid,
3497                 .seqno_idx = tid,
3498         };
3499         int i, diff;
3500
3501         if (WARN_ON(!pubsta || tid >= IEEE80211_NUM_TIDS))
3502                 return;
3503
3504         __skb_queue_head_init(&frames);
3505
3506         sta = container_of(pubsta, struct sta_info, sta);
3507
3508         rx.sta = sta;
3509         rx.sdata = sta->sdata;
3510         rx.local = sta->local;
3511
3512         rcu_read_lock();
3513         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
3514         if (!tid_agg_rx)
3515                 goto out;
3516
3517         spin_lock_bh(&tid_agg_rx->reorder_lock);
3518
3519         if (received_mpdus >= IEEE80211_SN_MODULO >> 1) {
3520                 int release;
3521
3522                 /* release all frames in the reorder buffer */
3523                 release = (tid_agg_rx->head_seq_num + tid_agg_rx->buf_size) %
3524                            IEEE80211_SN_MODULO;
3525                 ieee80211_release_reorder_frames(sta->sdata, tid_agg_rx,
3526                                                  release, &frames);
3527                 /* update ssn to match received ssn */
3528                 tid_agg_rx->head_seq_num = ssn;
3529         } else {
3530                 ieee80211_release_reorder_frames(sta->sdata, tid_agg_rx, ssn,
3531                                                  &frames);
3532         }
3533
3534         /* handle the case that received ssn is behind the mac ssn.
3535          * it can be tid_agg_rx->buf_size behind and still be valid */
3536         diff = (tid_agg_rx->head_seq_num - ssn) & IEEE80211_SN_MASK;
3537         if (diff >= tid_agg_rx->buf_size) {
3538                 tid_agg_rx->reorder_buf_filtered = 0;
3539                 goto release;
3540         }
3541         filtered = filtered >> diff;
3542         ssn += diff;
3543
3544         /* update bitmap */
3545         for (i = 0; i < tid_agg_rx->buf_size; i++) {
3546                 int index = (ssn + i) % tid_agg_rx->buf_size;
3547
3548                 tid_agg_rx->reorder_buf_filtered &= ~BIT_ULL(index);
3549                 if (filtered & BIT_ULL(i))
3550                         tid_agg_rx->reorder_buf_filtered |= BIT_ULL(index);
3551         }
3552
3553         /* now process also frames that the filter marking released */
3554         ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx, &frames);
3555
3556 release:
3557         spin_unlock_bh(&tid_agg_rx->reorder_lock);
3558
3559         ieee80211_rx_handlers(&rx, &frames);
3560
3561  out:
3562         rcu_read_unlock();
3563 }
3564 EXPORT_SYMBOL(ieee80211_mark_rx_ba_filtered_frames);
3565
3566 /* main receive path */
3567
3568 static bool ieee80211_accept_frame(struct ieee80211_rx_data *rx)
3569 {
3570         struct ieee80211_sub_if_data *sdata = rx->sdata;
3571         struct sk_buff *skb = rx->skb;
3572         struct ieee80211_hdr *hdr = (void *)skb->data;
3573         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3574         u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
3575         bool multicast = is_multicast_ether_addr(hdr->addr1);
3576
3577         switch (sdata->vif.type) {
3578         case NL80211_IFTYPE_STATION:
3579                 if (!bssid && !sdata->u.mgd.use_4addr)
3580                         return false;
3581                 if (multicast)
3582                         return true;
3583                 return ether_addr_equal(sdata->vif.addr, hdr->addr1);
3584         case NL80211_IFTYPE_ADHOC:
3585                 if (!bssid)
3586                         return false;
3587                 if (ether_addr_equal(sdata->vif.addr, hdr->addr2) ||
3588                     ether_addr_equal(sdata->u.ibss.bssid, hdr->addr2))
3589                         return false;
3590                 if (ieee80211_is_beacon(hdr->frame_control))
3591                         return true;
3592                 if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid))
3593                         return false;
3594                 if (!multicast &&
3595                     !ether_addr_equal(sdata->vif.addr, hdr->addr1))
3596                         return false;
3597                 if (!rx->sta) {
3598                         int rate_idx;
3599                         if (status->encoding != RX_ENC_LEGACY)
3600                                 rate_idx = 0; /* TODO: HT/VHT rates */
3601                         else
3602                                 rate_idx = status->rate_idx;
3603                         ieee80211_ibss_rx_no_sta(sdata, bssid, hdr->addr2,
3604                                                  BIT(rate_idx));
3605                 }
3606                 return true;
3607         case NL80211_IFTYPE_OCB:
3608                 if (!bssid)
3609                         return false;
3610                 if (!ieee80211_is_data_present(hdr->frame_control))
3611                         return false;
3612                 if (!is_broadcast_ether_addr(bssid))
3613                         return false;
3614                 if (!multicast &&
3615                     !ether_addr_equal(sdata->dev->dev_addr, hdr->addr1))
3616                         return false;
3617                 if (!rx->sta) {
3618                         int rate_idx;
3619                         if (status->encoding != RX_ENC_LEGACY)
3620                                 rate_idx = 0; /* TODO: HT rates */
3621                         else
3622                                 rate_idx = status->rate_idx;
3623                         ieee80211_ocb_rx_no_sta(sdata, bssid, hdr->addr2,
3624                                                 BIT(rate_idx));
3625                 }
3626                 return true;
3627         case NL80211_IFTYPE_MESH_POINT:
3628                 if (ether_addr_equal(sdata->vif.addr, hdr->addr2))
3629                         return false;
3630                 if (multicast)
3631                         return true;
3632                 return ether_addr_equal(sdata->vif.addr, hdr->addr1);
3633         case NL80211_IFTYPE_AP_VLAN:
3634         case NL80211_IFTYPE_AP:
3635                 if (!bssid)
3636                         return ether_addr_equal(sdata->vif.addr, hdr->addr1);
3637
3638                 if (!ieee80211_bssid_match(bssid, sdata->vif.addr)) {
3639                         /*
3640                          * Accept public action frames even when the
3641                          * BSSID doesn't match, this is used for P2P
3642                          * and location updates. Note that mac80211
3643                          * itself never looks at these frames.
3644                          */
3645                         if (!multicast &&
3646                             !ether_addr_equal(sdata->vif.addr, hdr->addr1))
3647                                 return false;
3648                         if (ieee80211_is_public_action(hdr, skb->len))
3649                                 return true;
3650                         return ieee80211_is_beacon(hdr->frame_control);
3651                 }
3652
3653                 if (!ieee80211_has_tods(hdr->frame_control)) {
3654                         /* ignore data frames to TDLS-peers */
3655                         if (ieee80211_is_data(hdr->frame_control))
3656                                 return false;
3657                         /* ignore action frames to TDLS-peers */
3658                         if (ieee80211_is_action(hdr->frame_control) &&
3659                             !is_broadcast_ether_addr(bssid) &&
3660                             !ether_addr_equal(bssid, hdr->addr1))
3661                                 return false;
3662                 }
3663
3664                 /*
3665                  * 802.11-2016 Table 9-26 says that for data frames, A1 must be
3666                  * the BSSID - we've checked that already but may have accepted
3667                  * the wildcard (ff:ff:ff:ff:ff:ff).
3668                  *
3669                  * It also says:
3670                  *      The BSSID of the Data frame is determined as follows:
3671                  *      a) If the STA is contained within an AP or is associated
3672                  *         with an AP, the BSSID is the address currently in use
3673                  *         by the STA contained in the AP.
3674                  *
3675                  * So we should not accept data frames with an address that's
3676                  * multicast.
3677                  *
3678                  * Accepting it also opens a security problem because stations
3679                  * could encrypt it with the GTK and inject traffic that way.
3680                  */
3681                 if (ieee80211_is_data(hdr->frame_control) && multicast)
3682                         return false;
3683
3684                 return true;
3685         case NL80211_IFTYPE_WDS:
3686                 if (bssid || !ieee80211_is_data(hdr->frame_control))
3687                         return false;
3688                 return ether_addr_equal(sdata->u.wds.remote_addr, hdr->addr2);
3689         case NL80211_IFTYPE_P2P_DEVICE:
3690                 return ieee80211_is_public_action(hdr, skb->len) ||
3691                        ieee80211_is_probe_req(hdr->frame_control) ||
3692                        ieee80211_is_probe_resp(hdr->frame_control) ||
3693                        ieee80211_is_beacon(hdr->frame_control);
3694         case NL80211_IFTYPE_NAN:
3695                 /* Currently no frames on NAN interface are allowed */
3696                 return false;
3697         default:
3698                 break;
3699         }
3700
3701         WARN_ON_ONCE(1);
3702         return false;
3703 }
3704
3705 void ieee80211_check_fast_rx(struct sta_info *sta)
3706 {
3707         struct ieee80211_sub_if_data *sdata = sta->sdata;
3708         struct ieee80211_local *local = sdata->local;
3709         struct ieee80211_key *key;
3710         struct ieee80211_fast_rx fastrx = {
3711                 .dev = sdata->dev,
3712                 .vif_type = sdata->vif.type,
3713                 .control_port_protocol = sdata->control_port_protocol,
3714         }, *old, *new = NULL;
3715         bool assign = false;
3716
3717         /* use sparse to check that we don't return without updating */
3718         __acquire(check_fast_rx);
3719
3720         BUILD_BUG_ON(sizeof(fastrx.rfc1042_hdr) != sizeof(rfc1042_header));
3721         BUILD_BUG_ON(sizeof(fastrx.rfc1042_hdr) != ETH_ALEN);
3722         ether_addr_copy(fastrx.rfc1042_hdr, rfc1042_header);
3723         ether_addr_copy(fastrx.vif_addr, sdata->vif.addr);
3724
3725         fastrx.uses_rss = ieee80211_hw_check(&local->hw, USES_RSS);
3726
3727         /* fast-rx doesn't do reordering */
3728         if (ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION) &&
3729             !ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER))
3730                 goto clear;
3731
3732         switch (sdata->vif.type) {
3733         case NL80211_IFTYPE_STATION:
3734                 /* 4-addr is harder to deal with, later maybe */
3735                 if (sdata->u.mgd.use_4addr)
3736                         goto clear;
3737                 /* software powersave is a huge mess, avoid all of it */
3738                 if (ieee80211_hw_check(&local->hw, PS_NULLFUNC_STACK))
3739                         goto clear;
3740                 if (ieee80211_hw_check(&local->hw, SUPPORTS_PS) &&
3741                     !ieee80211_hw_check(&local->hw, SUPPORTS_DYNAMIC_PS))
3742                         goto clear;
3743                 if (sta->sta.tdls) {
3744                         fastrx.da_offs = offsetof(struct ieee80211_hdr, addr1);
3745                         fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr2);
3746                         fastrx.expected_ds_bits = 0;
3747                 } else {
3748                         fastrx.sta_notify = sdata->u.mgd.probe_send_count > 0;
3749                         fastrx.da_offs = offsetof(struct ieee80211_hdr, addr1);
3750                         fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr3);
3751                         fastrx.expected_ds_bits =
3752                                 cpu_to_le16(IEEE80211_FCTL_FROMDS);
3753                 }
3754                 break;
3755         case NL80211_IFTYPE_AP_VLAN:
3756         case NL80211_IFTYPE_AP:
3757                 /* parallel-rx requires this, at least with calls to
3758                  * ieee80211_sta_ps_transition()
3759                  */
3760                 if (!ieee80211_hw_check(&local->hw, AP_LINK_PS))
3761                         goto clear;
3762                 fastrx.da_offs = offsetof(struct ieee80211_hdr, addr3);
3763                 fastrx.sa_offs = offsetof(struct ieee80211_hdr, addr2);
3764                 fastrx.expected_ds_bits = cpu_to_le16(IEEE80211_FCTL_TODS);
3765
3766                 fastrx.internal_forward =
3767                         !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
3768                         (sdata->vif.type != NL80211_IFTYPE_AP_VLAN ||
3769                          !sdata->u.vlan.sta);
3770                 break;
3771         default:
3772                 goto clear;
3773         }
3774
3775         if (!test_sta_flag(sta, WLAN_STA_AUTHORIZED))
3776                 goto clear;
3777
3778         rcu_read_lock();
3779         key = rcu_dereference(sta->ptk[sta->ptk_idx]);
3780         if (key) {
3781                 switch (key->conf.cipher) {
3782                 case WLAN_CIPHER_SUITE_TKIP:
3783                         /* we don't want to deal with MMIC in fast-rx */
3784                         goto clear_rcu;
3785                 case WLAN_CIPHER_SUITE_CCMP:
3786                 case WLAN_CIPHER_SUITE_CCMP_256:
3787                 case WLAN_CIPHER_SUITE_GCMP:
3788                 case WLAN_CIPHER_SUITE_GCMP_256:
3789                         break;
3790                 default:
3791                         /* we also don't want to deal with WEP or cipher scheme
3792                          * since those require looking up the key idx in the
3793                          * frame, rather than assuming the PTK is used
3794                          * (we need to revisit this once we implement the real
3795                          * PTK index, which is now valid in the spec, but we
3796                          * haven't implemented that part yet)
3797                          */
3798                         goto clear_rcu;
3799                 }
3800
3801                 fastrx.key = true;
3802                 fastrx.icv_len = key->conf.icv_len;
3803         }
3804
3805         assign = true;
3806  clear_rcu:
3807         rcu_read_unlock();
3808  clear:
3809         __release(check_fast_rx);
3810
3811         if (assign)
3812                 new = kmemdup(&fastrx, sizeof(fastrx), GFP_KERNEL);
3813
3814         spin_lock_bh(&sta->lock);
3815         old = rcu_dereference_protected(sta->fast_rx, true);
3816         rcu_assign_pointer(sta->fast_rx, new);
3817         spin_unlock_bh(&sta->lock);
3818
3819         if (old)
3820                 kfree_rcu(old, rcu_head);
3821 }
3822
3823 void ieee80211_clear_fast_rx(struct sta_info *sta)
3824 {
3825         struct ieee80211_fast_rx *old;
3826
3827         spin_lock_bh(&sta->lock);
3828         old = rcu_dereference_protected(sta->fast_rx, true);
3829         RCU_INIT_POINTER(sta->fast_rx, NULL);
3830         spin_unlock_bh(&sta->lock);
3831
3832         if (old)
3833                 kfree_rcu(old, rcu_head);
3834 }
3835
3836 void __ieee80211_check_fast_rx_iface(struct ieee80211_sub_if_data *sdata)
3837 {
3838         struct ieee80211_local *local = sdata->local;
3839         struct sta_info *sta;
3840
3841         lockdep_assert_held(&local->sta_mtx);
3842
3843         list_for_each_entry_rcu(sta, &local->sta_list, list) {
3844                 if (sdata != sta->sdata &&
3845                     (!sta->sdata->bss || sta->sdata->bss != sdata->bss))
3846                         continue;
3847                 ieee80211_check_fast_rx(sta);
3848         }
3849 }
3850
3851 void ieee80211_check_fast_rx_iface(struct ieee80211_sub_if_data *sdata)
3852 {
3853         struct ieee80211_local *local = sdata->local;
3854
3855         mutex_lock(&local->sta_mtx);
3856         __ieee80211_check_fast_rx_iface(sdata);
3857         mutex_unlock(&local->sta_mtx);
3858 }
3859
3860 static bool ieee80211_invoke_fast_rx(struct ieee80211_rx_data *rx,
3861                                      struct ieee80211_fast_rx *fast_rx)
3862 {
3863         struct sk_buff *skb = rx->skb;
3864         struct ieee80211_hdr *hdr = (void *)skb->data;
3865         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3866         struct sta_info *sta = rx->sta;
3867         int orig_len = skb->len;
3868         int snap_offs = ieee80211_hdrlen(hdr->frame_control);
3869         struct {
3870                 u8 snap[sizeof(rfc1042_header)];
3871                 __be16 proto;
3872         } *payload __aligned(2);
3873         struct {
3874                 u8 da[ETH_ALEN];
3875                 u8 sa[ETH_ALEN];
3876         } addrs __aligned(2);
3877         struct ieee80211_sta_rx_stats *stats = &sta->rx_stats;
3878
3879         if (fast_rx->uses_rss)
3880                 stats = this_cpu_ptr(sta->pcpu_rx_stats);
3881
3882         /* for parallel-rx, we need to have DUP_VALIDATED, otherwise we write
3883          * to a common data structure; drivers can implement that per queue
3884          * but we don't have that information in mac80211
3885          */
3886         if (!(status->flag & RX_FLAG_DUP_VALIDATED))
3887                 return false;
3888
3889 #define FAST_RX_CRYPT_FLAGS     (RX_FLAG_PN_VALIDATED | RX_FLAG_DECRYPTED)
3890
3891         /* If using encryption, we also need to have:
3892          *  - PN_VALIDATED: similar, but the implementation is tricky
3893          *  - DECRYPTED: necessary for PN_VALIDATED
3894          */
3895         if (fast_rx->key &&
3896             (status->flag & FAST_RX_CRYPT_FLAGS) != FAST_RX_CRYPT_FLAGS)
3897                 return false;
3898
3899         /* we don't deal with A-MSDU deaggregation here */
3900         if (status->rx_flags & IEEE80211_RX_AMSDU)
3901                 return false;
3902
3903         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
3904                 return false;
3905
3906         if (unlikely(ieee80211_is_frag(hdr)))
3907                 return false;
3908
3909         /* Since our interface address cannot be multicast, this
3910          * implicitly also rejects multicast frames without the
3911          * explicit check.
3912          *
3913          * We shouldn't get any *data* frames not addressed to us
3914          * (AP mode will accept multicast *management* frames), but
3915          * punting here will make it go through the full checks in
3916          * ieee80211_accept_frame().
3917          */
3918         if (!ether_addr_equal(fast_rx->vif_addr, hdr->addr1))
3919                 return false;
3920
3921         if ((hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_FROMDS |
3922                                               IEEE80211_FCTL_TODS)) !=
3923             fast_rx->expected_ds_bits)
3924                 goto drop;
3925
3926         /* assign the key to drop unencrypted frames (later)
3927          * and strip the IV/MIC if necessary
3928          */
3929         if (fast_rx->key && !(status->flag & RX_FLAG_IV_STRIPPED)) {
3930                 /* GCMP header length is the same */
3931                 snap_offs += IEEE80211_CCMP_HDR_LEN;
3932         }
3933
3934         if (!pskb_may_pull(skb, snap_offs + sizeof(*payload)))
3935                 goto drop;
3936         payload = (void *)(skb->data + snap_offs);
3937
3938         if (!ether_addr_equal(payload->snap, fast_rx->rfc1042_hdr))
3939                 return false;
3940
3941         /* Don't handle these here since they require special code.
3942          * Accept AARP and IPX even though they should come with a
3943          * bridge-tunnel header - but if we get them this way then
3944          * there's little point in discarding them.
3945          */
3946         if (unlikely(payload->proto == cpu_to_be16(ETH_P_TDLS) ||
3947                      payload->proto == fast_rx->control_port_protocol))
3948                 return false;
3949
3950         /* after this point, don't punt to the slowpath! */
3951
3952         if (rx->key && !(status->flag & RX_FLAG_MIC_STRIPPED) &&
3953             pskb_trim(skb, skb->len - fast_rx->icv_len))
3954                 goto drop;
3955
3956         if (unlikely(fast_rx->sta_notify)) {
3957                 ieee80211_sta_rx_notify(rx->sdata, hdr);
3958                 fast_rx->sta_notify = false;
3959         }
3960
3961         /* statistics part of ieee80211_rx_h_sta_process() */
3962         stats->last_rx = jiffies;
3963         stats->last_rate = sta_stats_encode_rate(status);
3964
3965         stats->fragments++;
3966         stats->packets++;
3967
3968         if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
3969                 stats->last_signal = status->signal;
3970                 if (!fast_rx->uses_rss)
3971                         ewma_signal_add(&sta->rx_stats_avg.signal,
3972                                         -status->signal);
3973         }
3974
3975         if (status->chains) {
3976                 int i;
3977
3978                 stats->chains = status->chains;
3979                 for (i = 0; i < ARRAY_SIZE(status->chain_signal); i++) {
3980                         int signal = status->chain_signal[i];
3981
3982                         if (!(status->chains & BIT(i)))
3983                                 continue;
3984
3985                         stats->chain_signal_last[i] = signal;
3986                         if (!fast_rx->uses_rss)
3987                                 ewma_signal_add(&sta->rx_stats_avg.chain_signal[i],
3988                                                 -signal);
3989                 }
3990         }
3991         /* end of statistics */
3992
3993         if (rx->key && !ieee80211_has_protected(hdr->frame_control))
3994                 goto drop;
3995
3996         /* do the header conversion - first grab the addresses */
3997         ether_addr_copy(addrs.da, skb->data + fast_rx->da_offs);
3998         ether_addr_copy(addrs.sa, skb->data + fast_rx->sa_offs);
3999         /* remove the SNAP but leave the ethertype */
4000         skb_pull(skb, snap_offs + sizeof(rfc1042_header));
4001         /* push the addresses in front */
4002         memcpy(skb_push(skb, sizeof(addrs)), &addrs, sizeof(addrs));
4003
4004         skb->dev = fast_rx->dev;
4005
4006         ieee80211_rx_stats(fast_rx->dev, skb->len);
4007
4008         /* The seqno index has the same property as needed
4009          * for the rx_msdu field, i.e. it is IEEE80211_NUM_TIDS
4010          * for non-QoS-data frames. Here we know it's a data
4011          * frame, so count MSDUs.
4012          */
4013         u64_stats_update_begin(&stats->syncp);
4014         stats->msdu[rx->seqno_idx]++;
4015         stats->bytes += orig_len;
4016         u64_stats_update_end(&stats->syncp);
4017
4018         if (fast_rx->internal_forward) {
4019                 struct sk_buff *xmit_skb = NULL;
4020                 bool multicast = is_multicast_ether_addr(skb->data);
4021
4022                 if (multicast) {
4023                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
4024                 } else if (sta_info_get(rx->sdata, skb->data)) {
4025                         xmit_skb = skb;
4026                         skb = NULL;
4027                 }
4028
4029                 if (xmit_skb) {
4030                         /*
4031                          * Send to wireless media and increase priority by 256
4032                          * to keep the received priority instead of
4033                          * reclassifying the frame (see cfg80211_classify8021d).
4034                          */
4035                         xmit_skb->priority += 256;
4036                         xmit_skb->protocol = htons(ETH_P_802_3);
4037                         skb_reset_network_header(xmit_skb);
4038                         skb_reset_mac_header(xmit_skb);
4039                         dev_queue_xmit(xmit_skb);
4040                 }
4041
4042                 if (!skb)
4043                         return true;
4044         }
4045
4046         /* deliver to local stack */
4047         skb->protocol = eth_type_trans(skb, fast_rx->dev);
4048         memset(skb->cb, 0, sizeof(skb->cb));
4049         if (rx->napi)
4050                 napi_gro_receive(rx->napi, skb);
4051         else
4052                 netif_receive_skb(skb);
4053
4054         return true;
4055  drop:
4056         dev_kfree_skb(skb);
4057         stats->dropped++;
4058         return true;
4059 }
4060
4061 /*
4062  * This function returns whether or not the SKB
4063  * was destined for RX processing or not, which,
4064  * if consume is true, is equivalent to whether
4065  * or not the skb was consumed.
4066  */
4067 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
4068                                             struct sk_buff *skb, bool consume)
4069 {
4070         struct ieee80211_local *local = rx->local;
4071         struct ieee80211_sub_if_data *sdata = rx->sdata;
4072
4073         rx->skb = skb;
4074
4075         /* See if we can do fast-rx; if we have to copy we already lost,
4076          * so punt in that case. We should never have to deliver a data
4077          * frame to multiple interfaces anyway.
4078          *
4079          * We skip the ieee80211_accept_frame() call and do the necessary
4080          * checking inside ieee80211_invoke_fast_rx().
4081          */
4082         if (consume && rx->sta) {
4083                 struct ieee80211_fast_rx *fast_rx;
4084
4085                 fast_rx = rcu_dereference(rx->sta->fast_rx);
4086                 if (fast_rx && ieee80211_invoke_fast_rx(rx, fast_rx))
4087                         return true;
4088         }
4089
4090         if (!ieee80211_accept_frame(rx))
4091                 return false;
4092
4093         if (!consume) {
4094                 skb = skb_copy(skb, GFP_ATOMIC);
4095                 if (!skb) {
4096                         if (net_ratelimit())
4097                                 wiphy_debug(local->hw.wiphy,
4098                                         "failed to copy skb for %s\n",
4099                                         sdata->name);
4100                         return true;
4101                 }
4102
4103                 rx->skb = skb;
4104         }
4105
4106         ieee80211_invoke_rx_handlers(rx);
4107         return true;
4108 }
4109
4110 /*
4111  * This is the actual Rx frames handler. as it belongs to Rx path it must
4112  * be called with rcu_read_lock protection.
4113  */
4114 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
4115                                          struct ieee80211_sta *pubsta,
4116                                          struct sk_buff *skb,
4117                                          struct napi_struct *napi)
4118 {
4119         struct ieee80211_local *local = hw_to_local(hw);
4120         struct ieee80211_sub_if_data *sdata;
4121         struct ieee80211_hdr *hdr;
4122         __le16 fc;
4123         struct ieee80211_rx_data rx;
4124         struct ieee80211_sub_if_data *prev;
4125         struct rhlist_head *tmp;
4126         int err = 0;
4127
4128         fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
4129         memset(&rx, 0, sizeof(rx));
4130         rx.skb = skb;
4131         rx.local = local;
4132         rx.napi = napi;
4133
4134         if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
4135                 I802_DEBUG_INC(local->dot11ReceivedFragmentCount);
4136
4137         if (ieee80211_is_mgmt(fc)) {
4138                 /* drop frame if too short for header */
4139                 if (skb->len < ieee80211_hdrlen(fc))
4140                         err = -ENOBUFS;
4141                 else
4142                         err = skb_linearize(skb);
4143         } else {
4144                 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
4145         }
4146
4147         if (err) {
4148                 dev_kfree_skb(skb);
4149                 return;
4150         }
4151
4152         hdr = (struct ieee80211_hdr *)skb->data;
4153         ieee80211_parse_qos(&rx);
4154         ieee80211_verify_alignment(&rx);
4155
4156         if (unlikely(ieee80211_is_probe_resp(hdr->frame_control) ||
4157                      ieee80211_is_beacon(hdr->frame_control)))
4158                 ieee80211_scan_rx(local, skb);
4159
4160         if (ieee80211_is_data(fc)) {
4161                 struct sta_info *sta, *prev_sta;
4162
4163                 if (pubsta) {
4164                         rx.sta = container_of(pubsta, struct sta_info, sta);
4165                         rx.sdata = rx.sta->sdata;
4166                         if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
4167                                 return;
4168                         goto out;
4169                 }
4170
4171                 prev_sta = NULL;
4172
4173                 for_each_sta_info(local, hdr->addr2, sta, tmp) {
4174                         if (!prev_sta) {
4175                                 prev_sta = sta;
4176                                 continue;
4177                         }
4178
4179                         rx.sta = prev_sta;
4180                         rx.sdata = prev_sta->sdata;
4181                         ieee80211_prepare_and_rx_handle(&rx, skb, false);
4182
4183                         prev_sta = sta;
4184                 }
4185
4186                 if (prev_sta) {
4187                         rx.sta = prev_sta;
4188                         rx.sdata = prev_sta->sdata;
4189
4190                         if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
4191                                 return;
4192                         goto out;
4193                 }
4194         }
4195
4196         prev = NULL;
4197
4198         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
4199                 if (!ieee80211_sdata_running(sdata))
4200                         continue;
4201
4202                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
4203                     sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
4204                         continue;
4205
4206                 /*
4207                  * frame is destined for this interface, but if it's
4208                  * not also for the previous one we handle that after
4209                  * the loop to avoid copying the SKB once too much
4210                  */
4211
4212                 if (!prev) {
4213                         prev = sdata;
4214                         continue;
4215                 }
4216
4217                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
4218                 rx.sdata = prev;
4219                 ieee80211_prepare_and_rx_handle(&rx, skb, false);
4220
4221                 prev = sdata;
4222         }
4223
4224         if (prev) {
4225                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
4226                 rx.sdata = prev;
4227
4228                 if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
4229                         return;
4230         }
4231
4232  out:
4233         dev_kfree_skb(skb);
4234 }
4235
4236 /*
4237  * This is the receive path handler. It is called by a low level driver when an
4238  * 802.11 MPDU is received from the hardware.
4239  */
4240 void ieee80211_rx_napi(struct ieee80211_hw *hw, struct ieee80211_sta *pubsta,
4241                        struct sk_buff *skb, struct napi_struct *napi)
4242 {
4243         struct ieee80211_local *local = hw_to_local(hw);
4244         struct ieee80211_rate *rate = NULL;
4245         struct ieee80211_supported_band *sband;
4246         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
4247
4248         WARN_ON_ONCE(softirq_count() == 0);
4249
4250         if (WARN_ON(status->band >= NUM_NL80211_BANDS))
4251                 goto drop;
4252
4253         sband = local->hw.wiphy->bands[status->band];
4254         if (WARN_ON(!sband))
4255                 goto drop;
4256
4257         /*
4258          * If we're suspending, it is possible although not too likely
4259          * that we'd be receiving frames after having already partially
4260          * quiesced the stack. We can't process such frames then since
4261          * that might, for example, cause stations to be added or other
4262          * driver callbacks be invoked.
4263          */
4264         if (unlikely(local->quiescing || local->suspended))
4265                 goto drop;
4266
4267         /* We might be during a HW reconfig, prevent Rx for the same reason */
4268         if (unlikely(local->in_reconfig))
4269                 goto drop;
4270
4271         /*
4272          * The same happens when we're not even started,
4273          * but that's worth a warning.
4274          */
4275         if (WARN_ON(!local->started))
4276                 goto drop;
4277
4278         if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
4279                 /*
4280                  * Validate the rate, unless a PLCP error means that
4281                  * we probably can't have a valid rate here anyway.
4282                  */
4283
4284                 switch (status->encoding) {
4285                 case RX_ENC_HT:
4286                         /*
4287                          * rate_idx is MCS index, which can be [0-76]
4288                          * as documented on:
4289                          *
4290                          * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
4291                          *
4292                          * Anything else would be some sort of driver or
4293                          * hardware error. The driver should catch hardware
4294                          * errors.
4295                          */
4296                         if (WARN(status->rate_idx > 76,
4297                                  "Rate marked as an HT rate but passed "
4298                                  "status->rate_idx is not "
4299                                  "an MCS index [0-76]: %d (0x%02x)\n",
4300                                  status->rate_idx,
4301                                  status->rate_idx))
4302                                 goto drop;
4303                         break;
4304                 case RX_ENC_VHT:
4305                         if (WARN_ONCE(status->rate_idx > 9 ||
4306                                       !status->nss ||
4307                                       status->nss > 8,
4308                                       "Rate marked as a VHT rate but data is invalid: MCS: %d, NSS: %d\n",
4309                                       status->rate_idx, status->nss))
4310                                 goto drop;
4311                         break;
4312                 default:
4313                         WARN_ON_ONCE(1);
4314                         /* fall through */
4315                 case RX_ENC_LEGACY:
4316                         if (WARN_ON(status->rate_idx >= sband->n_bitrates))
4317                                 goto drop;
4318                         rate = &sband->bitrates[status->rate_idx];
4319                 }
4320         }
4321
4322         status->rx_flags = 0;
4323
4324         /*
4325          * key references and virtual interfaces are protected using RCU
4326          * and this requires that we are in a read-side RCU section during
4327          * receive processing
4328          */
4329         rcu_read_lock();
4330
4331         /*
4332          * Frames with failed FCS/PLCP checksum are not returned,
4333          * all other frames are returned without radiotap header
4334          * if it was previously present.
4335          * Also, frames with less than 16 bytes are dropped.
4336          */
4337         skb = ieee80211_rx_monitor(local, skb, rate);
4338         if (!skb) {
4339                 rcu_read_unlock();
4340                 return;
4341         }
4342
4343         ieee80211_tpt_led_trig_rx(local,
4344                         ((struct ieee80211_hdr *)skb->data)->frame_control,
4345                         skb->len);
4346
4347         __ieee80211_rx_handle_packet(hw, pubsta, skb, napi);
4348
4349         rcu_read_unlock();
4350
4351         return;
4352  drop:
4353         kfree_skb(skb);
4354 }
4355 EXPORT_SYMBOL(ieee80211_rx_napi);
4356
4357 /* This is a version of the rx handler that can be called from hard irq
4358  * context. Post the skb on the queue and schedule the tasklet */
4359 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
4360 {
4361         struct ieee80211_local *local = hw_to_local(hw);
4362
4363         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
4364
4365         skb->pkt_type = IEEE80211_RX_MSG;
4366         skb_queue_tail(&local->skb_queue, skb);
4367         tasklet_schedule(&local->tasklet);
4368 }
4369 EXPORT_SYMBOL(ieee80211_rx_irqsafe);