net/mac80211/rx.c

   1 /*
   2  * Copyright 2002-2005, Instant802 Networks, Inc.
   3  * Copyright 2005-2006, Devicescape Software, Inc.
   4  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   5  * Copyright 2007-2010  Johannes Berg <johannes@sipsolutions.net>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/jiffies.h>
  13 #include <linux/slab.h>
  14 #include <linux/kernel.h>
  15 #include <linux/skbuff.h>
  16 #include <linux/netdevice.h>
  17 #include <linux/etherdevice.h>
  18 #include <linux/rcupdate.h>
  19 #include <linux/export.h>
  20 #include <net/mac80211.h>
  21 #include <net/ieee80211_radiotap.h>
  22 #include <asm/unaligned.h>
  23
  24 #include "ieee80211_i.h"
  25 #include "driver-ops.h"
  26 #include "led.h"
  27 #include "mesh.h"
  28 #include "wep.h"
  29 #include "wpa.h"
  30 #include "tkip.h"
  31 #include "wme.h"
  32 #include "rate.h"
  33
  34 /*
  35  * monitor mode reception
  36  *
  37  * This function cleans up the SKB, i.e. it removes all the stuff
  38  * only useful for monitoring.
  39  */
  40 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
  41                                            struct sk_buff *skb)
  42 {
  43         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  44
  45         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
  46                 if (likely(skb->len > FCS_LEN))
  47                         __pskb_trim(skb, skb->len - FCS_LEN);
  48                 else {
  49                         /* driver bug */
  50                         WARN_ON(1);
  51                         dev_kfree_skb(skb);
  52                         return NULL;
  53                 }
  54         }
  55
  56         if (status->vendor_radiotap_len)
  57                 __pskb_pull(skb, status->vendor_radiotap_len);
  58
  59         return skb;
  60 }
  61
  62 static inline int should_drop_frame(struct sk_buff *skb, int present_fcs_len)
  63 {
  64         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  65         struct ieee80211_hdr *hdr;
  66
  67         hdr = (void *)(skb->data + status->vendor_radiotap_len);
  68
  69         if (status->flag & (RX_FLAG_FAILED_FCS_CRC |
  70                             RX_FLAG_FAILED_PLCP_CRC |
  71                             RX_FLAG_AMPDU_IS_ZEROLEN))
  72                 return 1;
  73         if (unlikely(skb->len < 16 + present_fcs_len +
  74                                 status->vendor_radiotap_len))
  75                 return 1;
  76         if (ieee80211_is_ctl(hdr->frame_control) &&
  77             !ieee80211_is_pspoll(hdr->frame_control) &&
  78             !ieee80211_is_back_req(hdr->frame_control))
  79                 return 1;
  80         return 0;
  81 }
  82
  83 static int
  84 ieee80211_rx_radiotap_space(struct ieee80211_local *local,
  85                             struct ieee80211_rx_status *status)
  86 {
  87         int len;
  88
  89         /* always present fields */
  90         len = sizeof(struct ieee80211_radiotap_header) + 9;
  91
  92         /* allocate extra bitmap */
  93         if (status->vendor_radiotap_len)
  94                 len += 4;
  95
  96         if (ieee80211_have_rx_timestamp(status)) {
  97                 len = ALIGN(len, 8);
  98                 len += 8;
  99         }
 100         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
 101                 len += 1;
 102
 103         /* padding for RX_FLAGS if necessary */
 104         len = ALIGN(len, 2);
 105
 106         if (status->flag & RX_FLAG_HT) /* HT info */
 107                 len += 3;
 108
 109         if (status->flag & RX_FLAG_AMPDU_DETAILS) {
 110                 len = ALIGN(len, 4);
 111                 len += 8;
 112         }
 113
 114         if (status->flag & RX_FLAG_VHT) {
 115                 len = ALIGN(len, 2);
 116                 len += 12;
 117         }
 118
 119         if (status->vendor_radiotap_len) {
 120                 if (WARN_ON_ONCE(status->vendor_radiotap_align == 0))
 121                         status->vendor_radiotap_align = 1;
 122                 /* align standard part of vendor namespace */
 123                 len = ALIGN(len, 2);
 124                 /* allocate standard part of vendor namespace */
 125                 len += 6;
 126                 /* align vendor-defined part */
 127                 len = ALIGN(len, status->vendor_radiotap_align);
 128                 /* vendor-defined part is already in skb */
 129         }
 130
 131         return len;
 132 }
 133
 134 /*
 135  * ieee80211_add_rx_radiotap_header - add radiotap header
 136  *
 137  * add a radiotap header containing all the fields which the hardware provided.
 138  */
 139 static void
 140 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
 141                                  struct sk_buff *skb,
 142                                  struct ieee80211_rate *rate,
 143                                  int rtap_len, bool has_fcs)
 144 {
 145         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 146         struct ieee80211_radiotap_header *rthdr;
 147         unsigned char *pos;
 148         u16 rx_flags = 0;
 149         int mpdulen;
 150
 151         mpdulen = skb->len;
 152         if (!(has_fcs && (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)))
 153                 mpdulen += FCS_LEN;
 154
 155         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
 156         memset(rthdr, 0, rtap_len);
 157
 158         /* radiotap header, set always present flags */
 159         rthdr->it_present =
 160                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 161                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
 162                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
 163                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
 164         rthdr->it_len = cpu_to_le16(rtap_len + status->vendor_radiotap_len);
 165
 166         pos = (unsigned char *)(rthdr + 1);
 167
 168         if (status->vendor_radiotap_len) {
 169                 rthdr->it_present |=
 170                         cpu_to_le32(BIT(IEEE80211_RADIOTAP_VENDOR_NAMESPACE)) |
 171                         cpu_to_le32(BIT(IEEE80211_RADIOTAP_EXT));
 172                 put_unaligned_le32(status->vendor_radiotap_bitmap, pos);
 173                 pos += 4;
 174         }
 175
 176         /* the order of the following fields is important */
 177
 178         /* IEEE80211_RADIOTAP_TSFT */
 179         if (ieee80211_have_rx_timestamp(status)) {
 180                 /* padding */
 181                 while ((pos - (u8 *)rthdr) & 7)
 182                         *pos++ = 0;
 183                 put_unaligned_le64(
 184                         ieee80211_calculate_rx_timestamp(local, status,
 185                                                          mpdulen, 0),
 186                         pos);
 187                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
 188                 pos += 8;
 189         }
 190
 191         /* IEEE80211_RADIOTAP_FLAGS */
 192         if (has_fcs && (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS))
 193                 *pos |= IEEE80211_RADIOTAP_F_FCS;
 194         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 195                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
 196         if (status->flag & RX_FLAG_SHORTPRE)
 197                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
 198         pos++;
 199
 200         /* IEEE80211_RADIOTAP_RATE */
 201         if (!rate || status->flag & (RX_FLAG_HT | RX_FLAG_VHT)) {
 202                 /*
 203                  * Without rate information don't add it. If we have,
 204                  * MCS information is a separate field in radiotap,
 205                  * added below. The byte here is needed as padding
 206                  * for the channel though, so initialise it to 0.
 207                  */
 208                 *pos = 0;
 209         } else {
 210                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
 211                 *pos = rate->bitrate / 5;
 212         }
 213         pos++;
 214
 215         /* IEEE80211_RADIOTAP_CHANNEL */
 216         put_unaligned_le16(status->freq, pos);
 217         pos += 2;
 218         if (status->band == IEEE80211_BAND_5GHZ)
 219                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
 220                                    pos);
 221         else if (status->flag & (RX_FLAG_HT | RX_FLAG_VHT))
 222                 put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ,
 223                                    pos);
 224         else if (rate && rate->flags & IEEE80211_RATE_ERP_G)
 225                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
 226                                    pos);
 227         else if (rate)
 228                 put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
 229                                    pos);
 230         else
 231                 put_unaligned_le16(IEEE80211_CHAN_2GHZ, pos);
 232         pos += 2;
 233
 234         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
 235         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM &&
 236             !(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
 237                 *pos = status->signal;
 238                 rthdr->it_present |=
 239                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
 240                 pos++;
 241         }
 242
 243         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
 244
 245         /* IEEE80211_RADIOTAP_ANTENNA */
 246         *pos = status->antenna;
 247         pos++;
 248
 249         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
 250
 251         /* IEEE80211_RADIOTAP_RX_FLAGS */
 252         /* ensure 2 byte alignment for the 2 byte field as required */
 253         if ((pos - (u8 *)rthdr) & 1)
 254                 *pos++ = 0;
 255         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
 256                 rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
 257         put_unaligned_le16(rx_flags, pos);
 258         pos += 2;
 259
 260         if (status->flag & RX_FLAG_HT) {
 261                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
 262                 *pos++ = local->hw.radiotap_mcs_details;
 263                 *pos = 0;
 264                 if (status->flag & RX_FLAG_SHORT_GI)
 265                         *pos |= IEEE80211_RADIOTAP_MCS_SGI;
 266                 if (status->flag & RX_FLAG_40MHZ)
 267                         *pos |= IEEE80211_RADIOTAP_MCS_BW_40;
 268                 if (status->flag & RX_FLAG_HT_GF)
 269                         *pos |= IEEE80211_RADIOTAP_MCS_FMT_GF;
 270                 pos++;
 271                 *pos++ = status->rate_idx;
 272         }
 273
 274         if (status->flag & RX_FLAG_AMPDU_DETAILS) {
 275                 u16 flags = 0;
 276
 277                 /* ensure 4 byte alignment */
 278                 while ((pos - (u8 *)rthdr) & 3)
 279                         pos++;
 280                 rthdr->it_present |=
 281                         cpu_to_le32(1 << IEEE80211_RADIOTAP_AMPDU_STATUS);
 282                 put_unaligned_le32(status->ampdu_reference, pos);
 283                 pos += 4;
 284                 if (status->flag & RX_FLAG_AMPDU_REPORT_ZEROLEN)
 285                         flags |= IEEE80211_RADIOTAP_AMPDU_REPORT_ZEROLEN;
 286                 if (status->flag & RX_FLAG_AMPDU_IS_ZEROLEN)
 287                         flags |= IEEE80211_RADIOTAP_AMPDU_IS_ZEROLEN;
 288                 if (status->flag & RX_FLAG_AMPDU_LAST_KNOWN)
 289                         flags |= IEEE80211_RADIOTAP_AMPDU_LAST_KNOWN;
 290                 if (status->flag & RX_FLAG_AMPDU_IS_LAST)
 291                         flags |= IEEE80211_RADIOTAP_AMPDU_IS_LAST;
 292                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_ERROR)
 293                         flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_ERR;
 294                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
 295                         flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_KNOWN;
 296                 put_unaligned_le16(flags, pos);
 297                 pos += 2;
 298                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
 299                         *pos++ = status->ampdu_delimiter_crc;
 300                 else
 301                         *pos++ = 0;
 302                 *pos++ = 0;
 303         }
 304
 305         if (status->flag & RX_FLAG_VHT) {
 306                 u16 known = local->hw.radiotap_vht_details;
 307
 308                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_VHT);
 309                 /* known field - how to handle 80+80? */
 310                 if (status->flag & RX_FLAG_80P80MHZ)
 311                         known &= ~IEEE80211_RADIOTAP_VHT_KNOWN_BANDWIDTH;
 312                 put_unaligned_le16(known, pos);
 313                 pos += 2;
 314                 /* flags */
 315                 if (status->flag & RX_FLAG_SHORT_GI)
 316                         *pos |= IEEE80211_RADIOTAP_VHT_FLAG_SGI;
 317                 pos++;
 318                 /* bandwidth */
 319                 if (status->flag & RX_FLAG_80MHZ)
 320                         *pos++ = 4;
 321                 else if (status->flag & RX_FLAG_80P80MHZ)
 322                         *pos++ = 0; /* marked not known above */
 323                 else if (status->flag & RX_FLAG_160MHZ)
 324                         *pos++ = 11;
 325                 else if (status->flag & RX_FLAG_40MHZ)
 326                         *pos++ = 1;
 327                 else /* 20 MHz */
 328                         *pos++ = 0;
 329                 /* MCS/NSS */
 330                 *pos = (status->rate_idx << 4) | status->vht_nss;
 331                 pos += 4;
 332                 /* coding field */
 333                 pos++;
 334                 /* group ID */
 335                 pos++;
 336                 /* partial_aid */
 337                 pos += 2;
 338         }
 339
 340         if (status->vendor_radiotap_len) {
 341                 /* ensure 2 byte alignment for the vendor field as required */
 342                 if ((pos - (u8 *)rthdr) & 1)
 343                         *pos++ = 0;
 344                 *pos++ = status->vendor_radiotap_oui[0];
 345                 *pos++ = status->vendor_radiotap_oui[1];
 346                 *pos++ = status->vendor_radiotap_oui[2];
 347                 *pos++ = status->vendor_radiotap_subns;
 348                 put_unaligned_le16(status->vendor_radiotap_len, pos);
 349                 pos += 2;
 350                 /* align the actual payload as requested */
 351                 while ((pos - (u8 *)rthdr) & (status->vendor_radiotap_align - 1))
 352                         *pos++ = 0;
 353         }
 354 }
 355
 356 /*
 357  * This function copies a received frame to all monitor interfaces and
 358  * returns a cleaned-up SKB that no longer includes the FCS nor the
 359  * radiotap header the driver might have added.
 360  */
 361 static struct sk_buff *
 362 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
 363                      struct ieee80211_rate *rate)
 364 {
 365         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
 366         struct ieee80211_sub_if_data *sdata;
 367         int needed_headroom;
 368         struct sk_buff *skb, *skb2;
 369         struct net_device *prev_dev = NULL;
 370         int present_fcs_len = 0;
 371
 372         /*
 373          * First, we may need to make a copy of the skb because
 374          *  (1) we need to modify it for radiotap (if not present), and
 375          *  (2) the other RX handlers will modify the skb we got.
 376          *
 377          * We don't need to, of course, if we aren't going to return
 378          * the SKB because it has a bad FCS/PLCP checksum.
 379          */
 380
 381         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 382                 present_fcs_len = FCS_LEN;
 383
 384         /* ensure hdr->frame_control and vendor radiotap data are in skb head */
 385         if (!pskb_may_pull(origskb, 2 + status->vendor_radiotap_len)) {
 386                 dev_kfree_skb(origskb);
 387                 return NULL;
 388         }
 389
 390         if (!local->monitors) {
 391                 if (should_drop_frame(origskb, present_fcs_len)) {
 392                         dev_kfree_skb(origskb);
 393                         return NULL;
 394                 }
 395
 396                 return remove_monitor_info(local, origskb);
 397         }
 398
 399         /* room for the radiotap header based on driver features */
 400         needed_headroom = ieee80211_rx_radiotap_space(local, status);
 401
 402         if (should_drop_frame(origskb, present_fcs_len)) {
 403                 /* only need to expand headroom if necessary */
 404                 skb = origskb;
 405                 origskb = NULL;
 406
 407                 /*
 408                  * This shouldn't trigger often because most devices have an
 409                  * RX header they pull before we get here, and that should
 410                  * be big enough for our radiotap information. We should
 411                  * probably export the length to drivers so that we can have
 412                  * them allocate enough headroom to start with.
 413                  */
 414                 if (skb_headroom(skb) < needed_headroom &&
 415                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
 416                         dev_kfree_skb(skb);
 417                         return NULL;
 418                 }
 419         } else {
 420                 /*
 421                  * Need to make a copy and possibly remove radiotap header
 422                  * and FCS from the original.
 423                  */
 424                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
 425
 426                 origskb = remove_monitor_info(local, origskb);
 427
 428                 if (!skb)
 429                         return origskb;
 430         }
 431
 432         /* prepend radiotap information */
 433         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
 434                                          true);
 435
 436         skb_reset_mac_header(skb);
 437         skb->ip_summed = CHECKSUM_UNNECESSARY;
 438         skb->pkt_type = PACKET_OTHERHOST;
 439         skb->protocol = htons(ETH_P_802_2);
 440
 441         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 442                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
 443                         continue;
 444
 445                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
 446                         continue;
 447
 448                 if (!ieee80211_sdata_running(sdata))
 449                         continue;
 450
 451                 if (prev_dev) {
 452                         skb2 = skb_clone(skb, GFP_ATOMIC);
 453                         if (skb2) {
 454                                 skb2->dev = prev_dev;
 455                                 netif_receive_skb(skb2);
 456                         }
 457                 }
 458
 459                 prev_dev = sdata->dev;
 460                 sdata->dev->stats.rx_packets++;
 461                 sdata->dev->stats.rx_bytes += skb->len;
 462         }
 463
 464         if (prev_dev) {
 465                 skb->dev = prev_dev;
 466                 netif_receive_skb(skb);
 467         } else
 468                 dev_kfree_skb(skb);
 469
 470         return origskb;
 471 }
 472
 473 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
 474 {
 475         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 476         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 477         int tid, seqno_idx, security_idx;
 478
 479         /* does the frame have a qos control field? */
 480         if (ieee80211_is_data_qos(hdr->frame_control)) {
 481                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 482                 /* frame has qos control */
 483                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
 484                 if (*qc & IEEE80211_QOS_CTL_A_MSDU_PRESENT)
 485                         status->rx_flags |= IEEE80211_RX_AMSDU;
 486
 487                 seqno_idx = tid;
 488                 security_idx = tid;
 489         } else {
 490                 /*
 491                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
 492                  *
 493                  *      Sequence numbers for management frames, QoS data
 494                  *      frames with a broadcast/multicast address in the
 495                  *      Address 1 field, and all non-QoS data frames sent
 496                  *      by QoS STAs are assigned using an additional single
 497                  *      modulo-4096 counter, [...]
 498                  *
 499                  * We also use that counter for non-QoS STAs.
 500                  */
 501                 seqno_idx = IEEE80211_NUM_TIDS;
 502                 security_idx = 0;
 503                 if (ieee80211_is_mgmt(hdr->frame_control))
 504                         security_idx = IEEE80211_NUM_TIDS;
 505                 tid = 0;
 506         }
 507
 508         rx->seqno_idx = seqno_idx;
 509         rx->security_idx = security_idx;
 510         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 511          * For now, set skb->priority to 0 for other cases. */
 512         rx->skb->priority = (tid > 7) ? 0 : tid;
 513 }
 514
 515 /**
 516  * DOC: Packet alignment
 517  *
 518  * Drivers always need to pass packets that are aligned to two-byte boundaries
 519  * to the stack.
 520  *
 521  * Additionally, should, if possible, align the payload data in a way that
 522  * guarantees that the contained IP header is aligned to a four-byte
 523  * boundary. In the case of regular frames, this simply means aligning the
 524  * payload to a four-byte boundary (because either the IP header is directly
 525  * contained, or IV/RFC1042 headers that have a length divisible by four are
 526  * in front of it).  If the payload data is not properly aligned and the
 527  * architecture doesn't support efficient unaligned operations, mac80211
 528  * will align the data.
 529  *
 530  * With A-MSDU frames, however, the payload data address must yield two modulo
 531  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
 532  * push the IP header further back to a multiple of four again. Thankfully, the
 533  * specs were sane enough this time around to require padding each A-MSDU
 534  * subframe to a length that is a multiple of four.
 535  *
 536  * Padding like Atheros hardware adds which is between the 802.11 header and
 537  * the payload is not supported, the driver is required to move the 802.11
 538  * header to be directly in front of the payload in that case.
 539  */
 540 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
 541 {
 542 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 543         WARN_ONCE((unsigned long)rx->skb->data & 1,
 544                   "unaligned packet at 0x%p\n", rx->skb->data);
 545 #endif
 546 }
 547
 548
 549 /* rx handlers */
 550
 551 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
 552 {
 553         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 554
 555         if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
 556                 return 0;
 557
 558         return ieee80211_is_robust_mgmt_frame(hdr);
 559 }
 560
 561
 562 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
 563 {
 564         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 565
 566         if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
 567                 return 0;
 568
 569         return ieee80211_is_robust_mgmt_frame(hdr);
 570 }
 571
 572
 573 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
 574 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
 575 {
 576         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
 577         struct ieee80211_mmie *mmie;
 578
 579         if (skb->len < 24 + sizeof(*mmie) || !is_multicast_ether_addr(hdr->da))
 580                 return -1;
 581
 582         if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
 583                 return -1; /* not a robust management frame */
 584
 585         mmie = (struct ieee80211_mmie *)
 586                 (skb->data + skb->len - sizeof(*mmie));
 587         if (mmie->element_id != WLAN_EID_MMIE ||
 588             mmie->length != sizeof(*mmie) - 2)
 589                 return -1;
 590
 591         return le16_to_cpu(mmie->key_id);
 592 }
 593
 594 static ieee80211_rx_result ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
 595 {
 596         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 597         char *dev_addr = rx->sdata->vif.addr;
 598
 599         if (ieee80211_is_data(hdr->frame_control)) {
 600                 if (is_multicast_ether_addr(hdr->addr1)) {
 601                         if (ieee80211_has_tods(hdr->frame_control) ||
 602                             !ieee80211_has_fromds(hdr->frame_control))
 603                                 return RX_DROP_MONITOR;
 604                         if (ether_addr_equal(hdr->addr3, dev_addr))
 605                                 return RX_DROP_MONITOR;
 606                 } else {
 607                         if (!ieee80211_has_a4(hdr->frame_control))
 608                                 return RX_DROP_MONITOR;
 609                         if (ether_addr_equal(hdr->addr4, dev_addr))
 610                                 return RX_DROP_MONITOR;
 611                 }
 612         }
 613
 614         /* If there is not an established peer link and this is not a peer link
 615          * establisment frame, beacon or probe, drop the frame.
 616          */
 617
 618         if (!rx->sta || sta_plink_state(rx->sta) != NL80211_PLINK_ESTAB) {
 619                 struct ieee80211_mgmt *mgmt;
 620
 621                 if (!ieee80211_is_mgmt(hdr->frame_control))
 622                         return RX_DROP_MONITOR;
 623
 624                 if (ieee80211_is_action(hdr->frame_control)) {
 625                         u8 category;
 626
 627                         /* make sure category field is present */
 628                         if (rx->skb->len < IEEE80211_MIN_ACTION_SIZE)
 629                                 return RX_DROP_MONITOR;
 630
 631                         mgmt = (struct ieee80211_mgmt *)hdr;
 632                         category = mgmt->u.action.category;
 633                         if (category != WLAN_CATEGORY_MESH_ACTION &&
 634                             category != WLAN_CATEGORY_SELF_PROTECTED)
 635                                 return RX_DROP_MONITOR;
 636                         return RX_CONTINUE;
 637                 }
 638
 639                 if (ieee80211_is_probe_req(hdr->frame_control) ||
 640                     ieee80211_is_probe_resp(hdr->frame_control) ||
 641                     ieee80211_is_beacon(hdr->frame_control) ||
 642                     ieee80211_is_auth(hdr->frame_control))
 643                         return RX_CONTINUE;
 644
 645                 return RX_DROP_MONITOR;
 646         }
 647
 648         return RX_CONTINUE;
 649 }
 650
 651 #define SEQ_MODULO 0x1000
 652 #define SEQ_MASK   0xfff
 653
 654 static inline int seq_less(u16 sq1, u16 sq2)
 655 {
 656         return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
 657 }
 658
 659 static inline u16 seq_inc(u16 sq)
 660 {
 661         return (sq + 1) & SEQ_MASK;
 662 }
 663
 664 static inline u16 seq_sub(u16 sq1, u16 sq2)
 665 {
 666         return (sq1 - sq2) & SEQ_MASK;
 667 }
 668
 669 static void ieee80211_release_reorder_frame(struct ieee80211_sub_if_data *sdata,
 670                                             struct tid_ampdu_rx *tid_agg_rx,
 671                                             int index,
 672                                             struct sk_buff_head *frames)
 673 {
 674         struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
 675         struct ieee80211_rx_status *status;
 676
 677         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 678
 679         if (!skb)
 680                 goto no_frame;
 681
 682         /* release the frame from the reorder ring buffer */
 683         tid_agg_rx->stored_mpdu_num--;
 684         tid_agg_rx->reorder_buf[index] = NULL;
 685         status = IEEE80211_SKB_RXCB(skb);
 686         status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE;
 687         __skb_queue_tail(frames, skb);
 688
 689 no_frame:
 690         tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
 691 }
 692
 693 static void ieee80211_release_reorder_frames(struct ieee80211_sub_if_data *sdata,
 694                                              struct tid_ampdu_rx *tid_agg_rx,
 695                                              u16 head_seq_num,
 696                                              struct sk_buff_head *frames)
 697 {
 698         int index;
 699
 700         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 701
 702         while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
 703                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
 704                                                         tid_agg_rx->buf_size;
 705                 ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
 706                                                 frames);
 707         }
 708 }
 709
 710 /*
 711  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
 712  * the skb was added to the buffer longer than this time ago, the earlier
 713  * frames that have not yet been received are assumed to be lost and the skb
 714  * can be released for processing. This may also release other skb's from the
 715  * reorder buffer if there are no additional gaps between the frames.
 716  *
 717  * Callers must hold tid_agg_rx->reorder_lock.
 718  */
 719 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
 720
 721 static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata,
 722                                           struct tid_ampdu_rx *tid_agg_rx,
 723                                           struct sk_buff_head *frames)
 724 {
 725         int index, j;
 726
 727         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 728
 729         /* release the buffer until next missing frame */
 730         index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
 731                                                 tid_agg_rx->buf_size;
 732         if (!tid_agg_rx->reorder_buf[index] &&
 733             tid_agg_rx->stored_mpdu_num) {
 734                 /*
 735                  * No buffers ready to be released, but check whether any
 736                  * frames in the reorder buffer have timed out.
 737                  */
 738                 int skipped = 1;
 739                 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
 740                      j = (j + 1) % tid_agg_rx->buf_size) {
 741                         if (!tid_agg_rx->reorder_buf[j]) {
 742                                 skipped++;
 743                                 continue;
 744                         }
 745                         if (skipped &&
 746                             !time_after(jiffies, tid_agg_rx->reorder_time[j] +
 747                                         HT_RX_REORDER_BUF_TIMEOUT))
 748                                 goto set_release_timer;
 749
 750                         ht_dbg_ratelimited(sdata,
 751                                            "release an RX reorder frame due to timeout on earlier frames\n");
 752                         ieee80211_release_reorder_frame(sdata, tid_agg_rx, j,
 753                                                         frames);
 754
 755                         /*
 756                          * Increment the head seq# also for the skipped slots.
 757                          */
 758                         tid_agg_rx->head_seq_num =
 759                                 (tid_agg_rx->head_seq_num + skipped) & SEQ_MASK;
 760                         skipped = 0;
 761                 }
 762         } else while (tid_agg_rx->reorder_buf[index]) {
 763                 ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
 764                                                 frames);
 765                 index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
 766                                                         tid_agg_rx->buf_size;
 767         }
 768
 769         if (tid_agg_rx->stored_mpdu_num) {
 770                 j = index = seq_sub(tid_agg_rx->head_seq_num,
 771                                     tid_agg_rx->ssn) % tid_agg_rx->buf_size;
 772
 773                 for (; j != (index - 1) % tid_agg_rx->buf_size;
 774                      j = (j + 1) % tid_agg_rx->buf_size) {
 775                         if (tid_agg_rx->reorder_buf[j])
 776                                 break;
 777                 }
 778
 779  set_release_timer:
 780
 781                 mod_timer(&tid_agg_rx->reorder_timer,
 782                           tid_agg_rx->reorder_time[j] + 1 +
 783                           HT_RX_REORDER_BUF_TIMEOUT);
 784         } else {
 785                 del_timer(&tid_agg_rx->reorder_timer);
 786         }
 787 }
 788
 789 /*
 790  * As this function belongs to the RX path it must be under
 791  * rcu_read_lock protection. It returns false if the frame
 792  * can be processed immediately, true if it was consumed.
 793  */
 794 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_sub_if_data *sdata,
 795                                              struct tid_ampdu_rx *tid_agg_rx,
 796                                              struct sk_buff *skb,
 797                                              struct sk_buff_head *frames)
 798 {
 799         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 800         u16 sc = le16_to_cpu(hdr->seq_ctrl);
 801         u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
 802         u16 head_seq_num, buf_size;
 803         int index;
 804         bool ret = true;
 805
 806         spin_lock(&tid_agg_rx->reorder_lock);
 807
 808         buf_size = tid_agg_rx->buf_size;
 809         head_seq_num = tid_agg_rx->head_seq_num;
 810
 811         /* frame with out of date sequence number */
 812         if (seq_less(mpdu_seq_num, head_seq_num)) {
 813                 dev_kfree_skb(skb);
 814                 goto out;
 815         }
 816
 817         /*
 818          * If frame the sequence number exceeds our buffering window
 819          * size release some previous frames to make room for this one.
 820          */
 821         if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
 822                 head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
 823                 /* release stored frames up to new head to stack */
 824                 ieee80211_release_reorder_frames(sdata, tid_agg_rx,
 825                                                  head_seq_num, frames);
 826         }
 827
 828         /* Now the new frame is always in the range of the reordering buffer */
 829
 830         index = seq_sub(mpdu_seq_num, tid_agg_rx->ssn) % tid_agg_rx->buf_size;
 831
 832         /* check if we already stored this frame */
 833         if (tid_agg_rx->reorder_buf[index]) {
 834                 dev_kfree_skb(skb);
 835                 goto out;
 836         }
 837
 838         /*
 839          * If the current MPDU is in the right order and nothing else
 840          * is stored we can process it directly, no need to buffer it.
 841          * If it is first but there's something stored, we may be able
 842          * to release frames after this one.
 843          */
 844         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
 845             tid_agg_rx->stored_mpdu_num == 0) {
 846                 tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
 847                 ret = false;
 848                 goto out;
 849         }
 850
 851         /* put the frame in the reordering buffer */
 852         tid_agg_rx->reorder_buf[index] = skb;
 853         tid_agg_rx->reorder_time[index] = jiffies;
 854         tid_agg_rx->stored_mpdu_num++;
 855         ieee80211_sta_reorder_release(sdata, tid_agg_rx, frames);
 856
 857  out:
 858         spin_unlock(&tid_agg_rx->reorder_lock);
 859         return ret;
 860 }
 861
 862 /*
 863  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
 864  * true if the MPDU was buffered, false if it should be processed.
 865  */
 866 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
 867                                        struct sk_buff_head *frames)
 868 {
 869         struct sk_buff *skb = rx->skb;
 870         struct ieee80211_local *local = rx->local;
 871         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 872         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 873         struct sta_info *sta = rx->sta;
 874         struct tid_ampdu_rx *tid_agg_rx;
 875         u16 sc;
 876         u8 tid, ack_policy;
 877
 878         if (!ieee80211_is_data_qos(hdr->frame_control))
 879                 goto dont_reorder;
 880
 881         /*
 882          * filter the QoS data rx stream according to
 883          * STA/TID and check if this STA/TID is on aggregation
 884          */
 885
 886         if (!sta)
 887                 goto dont_reorder;
 888
 889         ack_policy = *ieee80211_get_qos_ctl(hdr) &
 890                      IEEE80211_QOS_CTL_ACK_POLICY_MASK;
 891         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
 892
 893         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
 894         if (!tid_agg_rx)
 895                 goto dont_reorder;
 896
 897         /* qos null data frames are excluded */
 898         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
 899                 goto dont_reorder;
 900
 901         /* not part of a BA session */
 902         if (ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
 903             ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_NORMAL)
 904                 goto dont_reorder;
 905
 906         /* not actually part of this BA session */
 907         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
 908                 goto dont_reorder;
 909
 910         /* new, potentially un-ordered, ampdu frame - process it */
 911
 912         /* reset session timer */
 913         if (tid_agg_rx->timeout)
 914                 tid_agg_rx->last_rx = jiffies;
 915
 916         /* if this mpdu is fragmented - terminate rx aggregation session */
 917         sc = le16_to_cpu(hdr->seq_ctrl);
 918         if (sc & IEEE80211_SCTL_FRAG) {
 919                 skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
 920                 skb_queue_tail(&rx->sdata->skb_queue, skb);
 921                 ieee80211_queue_work(&local->hw, &rx->sdata->work);
 922                 return;
 923         }
 924
 925         /*
 926          * No locking needed -- we will only ever process one
 927          * RX packet at a time, and thus own tid_agg_rx. All
 928          * other code manipulating it needs to (and does) make
 929          * sure that we cannot get to it any more before doing
 930          * anything with it.
 931          */
 932         if (ieee80211_sta_manage_reorder_buf(rx->sdata, tid_agg_rx, skb,
 933                                              frames))
 934                 return;
 935
 936  dont_reorder:
 937         __skb_queue_tail(frames, skb);
 938 }
 939
 940 static ieee80211_rx_result debug_noinline
 941 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
 942 {
 943         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 944         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 945
 946         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 947         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 948                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
 949                              rx->sta->last_seq_ctrl[rx->seqno_idx] ==
 950                              hdr->seq_ctrl)) {
 951                         if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
 952                                 rx->local->dot11FrameDuplicateCount++;
 953                                 rx->sta->num_duplicates++;
 954                         }
 955                         return RX_DROP_UNUSABLE;
 956                 } else
 957                         rx->sta->last_seq_ctrl[rx->seqno_idx] = hdr->seq_ctrl;
 958         }
 959
 960         if (unlikely(rx->skb->len < 16)) {
 961                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 962                 return RX_DROP_MONITOR;
 963         }
 964
 965         /* Drop disallowed frame classes based on STA auth/assoc state;
 966          * IEEE 802.11, Chap 5.5.
 967          *
 968          * mac80211 filters only based on association state, i.e. it drops
 969          * Class 3 frames from not associated stations. hostapd sends
 970          * deauth/disassoc frames when needed. In addition, hostapd is
 971          * responsible for filtering on both auth and assoc states.
 972          */
 973
 974         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
 975                 return ieee80211_rx_mesh_check(rx);
 976
 977         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
 978                       ieee80211_is_pspoll(hdr->frame_control)) &&
 979                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
 980                      rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
 981                      (!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_ASSOC)))) {
 982                 /*
 983                  * accept port control frames from the AP even when it's not
 984                  * yet marked ASSOC to prevent a race where we don't set the
 985                  * assoc bit quickly enough before it sends the first frame
 986                  */
 987                 if (rx->sta && rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
 988                     ieee80211_is_data_present(hdr->frame_control)) {
 989                         unsigned int hdrlen;
 990                         __be16 ethertype;
 991
 992                         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 993
 994                         if (rx->skb->len < hdrlen + 8)
 995                                 return RX_DROP_MONITOR;
 996
 997                         skb_copy_bits(rx->skb, hdrlen + 6, &ethertype, 2);
 998                         if (ethertype == rx->sdata->control_port_protocol)
 999                                 return RX_CONTINUE;
1000                 }
1001
1002                 if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
1003                     cfg80211_rx_spurious_frame(rx->sdata->dev,
1004                                                hdr->addr2,
1005                                                GFP_ATOMIC))
1006                         return RX_DROP_UNUSABLE;
1007
1008                 return RX_DROP_MONITOR;
1009         }
1010
1011         return RX_CONTINUE;
1012 }
1013
1014
1015 static ieee80211_rx_result debug_noinline
1016 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
1017 {
1018         struct sk_buff *skb = rx->skb;
1019         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1020         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1021         int keyidx;
1022         int hdrlen;
1023         ieee80211_rx_result result = RX_DROP_UNUSABLE;
1024         struct ieee80211_key *sta_ptk = NULL;
1025         int mmie_keyidx = -1;
1026         __le16 fc;
1027
1028         /*
1029          * Key selection 101
1030          *
1031          * There are four types of keys:
1032          *  - GTK (group keys)
1033          *  - IGTK (group keys for management frames)
1034          *  - PTK (pairwise keys)
1035          *  - STK (station-to-station pairwise keys)
1036          *
1037          * When selecting a key, we have to distinguish between multicast
1038          * (including broadcast) and unicast frames, the latter can only
1039          * use PTKs and STKs while the former always use GTKs and IGTKs.
1040          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
1041          * unicast frames can also use key indices like GTKs. Hence, if we
1042          * don't have a PTK/STK we check the key index for a WEP key.
1043          *
1044          * Note that in a regular BSS, multicast frames are sent by the
1045          * AP only, associated stations unicast the frame to the AP first
1046          * which then multicasts it on their behalf.
1047          *
1048          * There is also a slight problem in IBSS mode: GTKs are negotiated
1049          * with each station, that is something we don't currently handle.
1050          * The spec seems to expect that one negotiates the same key with
1051          * every station but there's no such requirement; VLANs could be
1052          * possible.
1053          */
1054
1055         /*
1056          * No point in finding a key and decrypting if the frame is neither
1057          * addressed to us nor a multicast frame.
1058          */
1059         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1060                 return RX_CONTINUE;
1061
1062         /* start without a key */
1063         rx->key = NULL;
1064
1065         if (rx->sta)
1066                 sta_ptk = rcu_dereference(rx->sta->ptk);
1067
1068         fc = hdr->frame_control;
1069
1070         if (!ieee80211_has_protected(fc))
1071                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
1072
1073         if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
1074                 rx->key = sta_ptk;
1075                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1076                     (status->flag & RX_FLAG_IV_STRIPPED))
1077                         return RX_CONTINUE;
1078                 /* Skip decryption if the frame is not protected. */
1079                 if (!ieee80211_has_protected(fc))
1080                         return RX_CONTINUE;
1081         } else if (mmie_keyidx >= 0) {
1082                 /* Broadcast/multicast robust management frame / BIP */
1083                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1084                     (status->flag & RX_FLAG_IV_STRIPPED))
1085                         return RX_CONTINUE;
1086
1087                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
1088                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
1089                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
1090                 if (rx->sta)
1091                         rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
1092                 if (!rx->key)
1093                         rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
1094         } else if (!ieee80211_has_protected(fc)) {
1095                 /*
1096                  * The frame was not protected, so skip decryption. However, we
1097                  * need to set rx->key if there is a key that could have been
1098                  * used so that the frame may be dropped if encryption would
1099                  * have been expected.
1100                  */
1101                 struct ieee80211_key *key = NULL;
1102                 struct ieee80211_sub_if_data *sdata = rx->sdata;
1103                 int i;
1104
1105                 if (ieee80211_is_mgmt(fc) &&
1106                     is_multicast_ether_addr(hdr->addr1) &&
1107                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
1108                         rx->key = key;
1109                 else {
1110                         if (rx->sta) {
1111                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1112                                         key = rcu_dereference(rx->sta->gtk[i]);
1113                                         if (key)
1114                                                 break;
1115                                 }
1116                         }
1117                         if (!key) {
1118                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1119                                         key = rcu_dereference(sdata->keys[i]);
1120                                         if (key)
1121                                                 break;
1122                                 }
1123                         }
1124                         if (key)
1125                                 rx->key = key;
1126                 }
1127                 return RX_CONTINUE;
1128         } else {
1129                 u8 keyid;
1130                 /*
1131                  * The device doesn't give us the IV so we won't be
1132                  * able to look up the key. That's ok though, we
1133                  * don't need to decrypt the frame, we just won't
1134                  * be able to keep statistics accurate.
1135                  * Except for key threshold notifications, should
1136                  * we somehow allow the driver to tell us which key
1137                  * the hardware used if this flag is set?
1138                  */
1139                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1140                     (status->flag & RX_FLAG_IV_STRIPPED))
1141                         return RX_CONTINUE;
1142
1143                 hdrlen = ieee80211_hdrlen(fc);
1144
1145                 if (rx->skb->len < 8 + hdrlen)
1146                         return RX_DROP_UNUSABLE; /* TODO: count this? */
1147
1148                 /*
1149                  * no need to call ieee80211_wep_get_keyidx,
1150                  * it verifies a bunch of things we've done already
1151                  */
1152                 skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
1153                 keyidx = keyid >> 6;
1154
1155                 /* check per-station GTK first, if multicast packet */
1156                 if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
1157                         rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
1158
1159                 /* if not found, try default key */
1160                 if (!rx->key) {
1161                         rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
1162
1163                         /*
1164                          * RSNA-protected unicast frames should always be
1165                          * sent with pairwise or station-to-station keys,
1166                          * but for WEP we allow using a key index as well.
1167                          */
1168                         if (rx->key &&
1169                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1170                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1171                             !is_multicast_ether_addr(hdr->addr1))
1172                                 rx->key = NULL;
1173                 }
1174         }
1175
1176         if (rx->key) {
1177                 if (unlikely(rx->key->flags & KEY_FLAG_TAINTED))
1178                         return RX_DROP_MONITOR;
1179
1180                 rx->key->tx_rx_count++;
1181                 /* TODO: add threshold stuff again */
1182         } else {
1183                 return RX_DROP_MONITOR;
1184         }
1185
1186         switch (rx->key->conf.cipher) {
1187         case WLAN_CIPHER_SUITE_WEP40:
1188         case WLAN_CIPHER_SUITE_WEP104:
1189                 result = ieee80211_crypto_wep_decrypt(rx);
1190                 break;
1191         case WLAN_CIPHER_SUITE_TKIP:
1192                 result = ieee80211_crypto_tkip_decrypt(rx);
1193                 break;
1194         case WLAN_CIPHER_SUITE_CCMP:
1195                 result = ieee80211_crypto_ccmp_decrypt(rx);
1196                 break;
1197         case WLAN_CIPHER_SUITE_AES_CMAC:
1198                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
1199                 break;
1200         default:
1201                 /*
1202                  * We can reach here only with HW-only algorithms
1203                  * but why didn't it decrypt the frame?!
1204                  */
1205                 return RX_DROP_UNUSABLE;
1206         }
1207
1208         /* the hdr variable is invalid after the decrypt handlers */
1209
1210         /* either the frame has been decrypted or will be dropped */
1211         status->flag |= RX_FLAG_DECRYPTED;
1212
1213         return result;
1214 }
1215
1216 static ieee80211_rx_result debug_noinline
1217 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1218 {
1219         struct ieee80211_local *local;
1220         struct ieee80211_hdr *hdr;
1221         struct sk_buff *skb;
1222
1223         local = rx->local;
1224         skb = rx->skb;
1225         hdr = (struct ieee80211_hdr *) skb->data;
1226
1227         if (!local->pspolling)
1228                 return RX_CONTINUE;
1229
1230         if (!ieee80211_has_fromds(hdr->frame_control))
1231                 /* this is not from AP */
1232                 return RX_CONTINUE;
1233
1234         if (!ieee80211_is_data(hdr->frame_control))
1235                 return RX_CONTINUE;
1236
1237         if (!ieee80211_has_moredata(hdr->frame_control)) {
1238                 /* AP has no more frames buffered for us */
1239                 local->pspolling = false;
1240                 return RX_CONTINUE;
1241         }
1242
1243         /* more data bit is set, let's request a new frame from the AP */
1244         ieee80211_send_pspoll(local, rx->sdata);
1245
1246         return RX_CONTINUE;
1247 }
1248
1249 static void sta_ps_start(struct sta_info *sta)
1250 {
1251         struct ieee80211_sub_if_data *sdata = sta->sdata;
1252         struct ieee80211_local *local = sdata->local;
1253         struct ps_data *ps;
1254
1255         if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
1256             sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1257                 ps = &sdata->bss->ps;
1258         else
1259                 return;
1260
1261         atomic_inc(&ps->num_sta_ps);
1262         set_sta_flag(sta, WLAN_STA_PS_STA);
1263         if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
1264                 drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1265         ps_dbg(sdata, "STA %pM aid %d enters power save mode\n",
1266                sta->sta.addr, sta->sta.aid);
1267 }
1268
1269 static void sta_ps_end(struct sta_info *sta)
1270 {
1271         ps_dbg(sta->sdata, "STA %pM aid %d exits power save mode\n",
1272                sta->sta.addr, sta->sta.aid);
1273
1274         if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) {
1275                 ps_dbg(sta->sdata, "STA %pM aid %d driver-ps-blocked\n",
1276                        sta->sta.addr, sta->sta.aid);
1277                 return;
1278         }
1279
1280         ieee80211_sta_ps_deliver_wakeup(sta);
1281 }
1282
1283 int ieee80211_sta_ps_transition(struct ieee80211_sta *sta, bool start)
1284 {
1285         struct sta_info *sta_inf = container_of(sta, struct sta_info, sta);
1286         bool in_ps;
1287
1288         WARN_ON(!(sta_inf->local->hw.flags & IEEE80211_HW_AP_LINK_PS));
1289
1290         /* Don't let the same PS state be set twice */
1291         in_ps = test_sta_flag(sta_inf, WLAN_STA_PS_STA);
1292         if ((start && in_ps) || (!start && !in_ps))
1293                 return -EINVAL;
1294
1295         if (start)
1296                 sta_ps_start(sta_inf);
1297         else
1298                 sta_ps_end(sta_inf);
1299
1300         return 0;
1301 }
1302 EXPORT_SYMBOL(ieee80211_sta_ps_transition);
1303
1304 static ieee80211_rx_result debug_noinline
1305 ieee80211_rx_h_uapsd_and_pspoll(struct ieee80211_rx_data *rx)
1306 {
1307         struct ieee80211_sub_if_data *sdata = rx->sdata;
1308         struct ieee80211_hdr *hdr = (void *)rx->skb->data;
1309         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1310         int tid, ac;
1311
1312         if (!rx->sta || !(status->rx_flags & IEEE80211_RX_RA_MATCH))
1313                 return RX_CONTINUE;
1314
1315         if (sdata->vif.type != NL80211_IFTYPE_AP &&
1316             sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
1317                 return RX_CONTINUE;
1318
1319         /*
1320          * The device handles station powersave, so don't do anything about
1321          * uAPSD and PS-Poll frames (the latter shouldn't even come up from
1322          * it to mac80211 since they're handled.)
1323          */
1324         if (sdata->local->hw.flags & IEEE80211_HW_AP_LINK_PS)
1325                 return RX_CONTINUE;
1326
1327         /*
1328          * Don't do anything if the station isn't already asleep. In
1329          * the uAPSD case, the station will probably be marked asleep,
1330          * in the PS-Poll case the station must be confused ...
1331          */
1332         if (!test_sta_flag(rx->sta, WLAN_STA_PS_STA))
1333                 return RX_CONTINUE;
1334
1335         if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) {
1336                 if (!test_sta_flag(rx->sta, WLAN_STA_SP)) {
1337                         if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1338                                 ieee80211_sta_ps_deliver_poll_response(rx->sta);
1339                         else
1340                                 set_sta_flag(rx->sta, WLAN_STA_PSPOLL);
1341                 }
1342
1343                 /* Free PS Poll skb here instead of returning RX_DROP that would
1344                  * count as an dropped frame. */
1345                 dev_kfree_skb(rx->skb);
1346
1347                 return RX_QUEUED;
1348         } else if (!ieee80211_has_morefrags(hdr->frame_control) &&
1349                    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1350                    ieee80211_has_pm(hdr->frame_control) &&
1351                    (ieee80211_is_data_qos(hdr->frame_control) ||
1352                     ieee80211_is_qos_nullfunc(hdr->frame_control))) {
1353                 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
1354                 ac = ieee802_1d_to_ac[tid & 7];
1355
1356                 /*
1357                  * If this AC is not trigger-enabled do nothing.
1358                  *
1359                  * NB: This could/should check a separate bitmap of trigger-
1360                  * enabled queues, but for now we only implement uAPSD w/o
1361                  * TSPEC changes to the ACs, so they're always the same.
1362                  */
1363                 if (!(rx->sta->sta.uapsd_queues & BIT(ac)))
1364                         return RX_CONTINUE;
1365
1366                 /* if we are in a service period, do nothing */
1367                 if (test_sta_flag(rx->sta, WLAN_STA_SP))
1368                         return RX_CONTINUE;
1369
1370                 if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1371                         ieee80211_sta_ps_deliver_uapsd(rx->sta);
1372                 else
1373                         set_sta_flag(rx->sta, WLAN_STA_UAPSD);
1374         }
1375
1376         return RX_CONTINUE;
1377 }
1378
1379 static ieee80211_rx_result debug_noinline
1380 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1381 {
1382         struct sta_info *sta = rx->sta;
1383         struct sk_buff *skb = rx->skb;
1384         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1385         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1386
1387         if (!sta)
1388                 return RX_CONTINUE;
1389
1390         /*
1391          * Update last_rx only for IBSS packets which are for the current
1392          * BSSID and for station already AUTHORIZED to avoid keeping the
1393          * current IBSS network alive in cases where other STAs start
1394          * using different BSSID. This will also give the station another
1395          * chance to restart the authentication/authorization in case
1396          * something went wrong the first time.
1397          */
1398         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1399                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1400                                                 NL80211_IFTYPE_ADHOC);
1401                 if (ether_addr_equal(bssid, rx->sdata->u.ibss.bssid) &&
1402                     test_sta_flag(sta, WLAN_STA_AUTHORIZED)) {
1403                         sta->last_rx = jiffies;
1404                         if (ieee80211_is_data(hdr->frame_control)) {
1405                                 sta->last_rx_rate_idx = status->rate_idx;
1406                                 sta->last_rx_rate_flag = status->flag;
1407                                 sta->last_rx_rate_vht_nss = status->vht_nss;
1408                         }
1409                 }
1410         } else if (!is_multicast_ether_addr(hdr->addr1)) {
1411                 /*
1412                  * Mesh beacons will update last_rx when if they are found to
1413                  * match the current local configuration when processed.
1414                  */
1415                 sta->last_rx = jiffies;
1416                 if (ieee80211_is_data(hdr->frame_control)) {
1417                         sta->last_rx_rate_idx = status->rate_idx;
1418                         sta->last_rx_rate_flag = status->flag;
1419                         sta->last_rx_rate_vht_nss = status->vht_nss;
1420                 }
1421         }
1422
1423         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1424                 return RX_CONTINUE;
1425
1426         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1427                 ieee80211_sta_rx_notify(rx->sdata, hdr);
1428
1429         sta->rx_fragments++;
1430         sta->rx_bytes += rx->skb->len;
1431         if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
1432                 sta->last_signal = status->signal;
1433                 ewma_add(&sta->avg_signal, -status->signal);
1434         }
1435
1436         /*
1437          * Change STA power saving mode only at the end of a frame
1438          * exchange sequence.
1439          */
1440         if (!(sta->local->hw.flags & IEEE80211_HW_AP_LINK_PS) &&
1441             !ieee80211_has_morefrags(hdr->frame_control) &&
1442             !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1443             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1444              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1445                 if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
1446                         /*
1447                          * Ignore doze->wake transitions that are
1448                          * indicated by non-data frames, the standard
1449                          * is unclear here, but for example going to
1450                          * PS mode and then scanning would cause a
1451                          * doze->wake transition for the probe request,
1452                          * and that is clearly undesirable.
1453                          */
1454                         if (ieee80211_is_data(hdr->frame_control) &&
1455                             !ieee80211_has_pm(hdr->frame_control))
1456                                 sta_ps_end(sta);
1457                 } else {
1458                         if (ieee80211_has_pm(hdr->frame_control))
1459                                 sta_ps_start(sta);
1460                 }
1461         }
1462
1463         /* mesh power save support */
1464         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
1465                 ieee80211_mps_rx_h_sta_process(sta, hdr);
1466
1467         /*
1468          * Drop (qos-)data::nullfunc frames silently, since they
1469          * are used only to control station power saving mode.
1470          */
1471         if (ieee80211_is_nullfunc(hdr->frame_control) ||
1472             ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1473                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1474
1475                 /*
1476                  * If we receive a 4-addr nullfunc frame from a STA
1477                  * that was not moved to a 4-addr STA vlan yet send
1478                  * the event to userspace and for older hostapd drop
1479                  * the frame to the monitor interface.
1480                  */
1481                 if (ieee80211_has_a4(hdr->frame_control) &&
1482                     (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1483                      (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1484                       !rx->sdata->u.vlan.sta))) {
1485                         if (!test_and_set_sta_flag(sta, WLAN_STA_4ADDR_EVENT))
1486                                 cfg80211_rx_unexpected_4addr_frame(
1487                                         rx->sdata->dev, sta->sta.addr,
1488                                         GFP_ATOMIC);
1489                         return RX_DROP_MONITOR;
1490                 }
1491                 /*
1492                  * Update counter and free packet here to avoid
1493                  * counting this as a dropped packed.
1494                  */
1495                 sta->rx_packets++;
1496                 dev_kfree_skb(rx->skb);
1497                 return RX_QUEUED;
1498         }
1499
1500         return RX_CONTINUE;
1501 } /* ieee80211_rx_h_sta_process */
1502
1503 static inline struct ieee80211_fragment_entry *
1504 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1505                          unsigned int frag, unsigned int seq, int rx_queue,
1506                          struct sk_buff **skb)
1507 {
1508         struct ieee80211_fragment_entry *entry;
1509
1510         entry = &sdata->fragments[sdata->fragment_next++];
1511         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1512                 sdata->fragment_next = 0;
1513
1514         if (!skb_queue_empty(&entry->skb_list))
1515                 __skb_queue_purge(&entry->skb_list);
1516
1517         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1518         *skb = NULL;
1519         entry->first_frag_time = jiffies;
1520         entry->seq = seq;
1521         entry->rx_queue = rx_queue;
1522         entry->last_frag = frag;
1523         entry->ccmp = 0;
1524         entry->extra_len = 0;
1525
1526         return entry;
1527 }
1528
1529 static inline struct ieee80211_fragment_entry *
1530 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1531                           unsigned int frag, unsigned int seq,
1532                           int rx_queue, struct ieee80211_hdr *hdr)
1533 {
1534         struct ieee80211_fragment_entry *entry;
1535         int i, idx;
1536
1537         idx = sdata->fragment_next;
1538         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1539                 struct ieee80211_hdr *f_hdr;
1540
1541                 idx--;
1542                 if (idx < 0)
1543                         idx = IEEE80211_FRAGMENT_MAX - 1;
1544
1545                 entry = &sdata->fragments[idx];
1546                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1547                     entry->rx_queue != rx_queue ||
1548                     entry->last_frag + 1 != frag)
1549                         continue;
1550
1551                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1552
1553                 /*
1554                  * Check ftype and addresses are equal, else check next fragment
1555                  */
1556                 if (((hdr->frame_control ^ f_hdr->frame_control) &
1557                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1558                     !ether_addr_equal(hdr->addr1, f_hdr->addr1) ||
1559                     !ether_addr_equal(hdr->addr2, f_hdr->addr2))
1560                         continue;
1561
1562                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1563                         __skb_queue_purge(&entry->skb_list);
1564                         continue;
1565                 }
1566                 return entry;
1567         }
1568
1569         return NULL;
1570 }
1571
1572 static ieee80211_rx_result debug_noinline
1573 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1574 {
1575         struct ieee80211_hdr *hdr;
1576         u16 sc;
1577         __le16 fc;
1578         unsigned int frag, seq;
1579         struct ieee80211_fragment_entry *entry;
1580         struct sk_buff *skb;
1581         struct ieee80211_rx_status *status;
1582
1583         hdr = (struct ieee80211_hdr *)rx->skb->data;
1584         fc = hdr->frame_control;
1585
1586         if (ieee80211_is_ctl(fc))
1587                 return RX_CONTINUE;
1588
1589         sc = le16_to_cpu(hdr->seq_ctrl);
1590         frag = sc & IEEE80211_SCTL_FRAG;
1591
1592         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1593                    is_multicast_ether_addr(hdr->addr1))) {
1594                 /* not fragmented */
1595                 goto out;
1596         }
1597         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1598
1599         if (skb_linearize(rx->skb))
1600                 return RX_DROP_UNUSABLE;
1601
1602         /*
1603          *  skb_linearize() might change the skb->data and
1604          *  previously cached variables (in this case, hdr) need to
1605          *  be refreshed with the new data.
1606          */
1607         hdr = (struct ieee80211_hdr *)rx->skb->data;
1608         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1609
1610         if (frag == 0) {
1611                 /* This is the first fragment of a new frame. */
1612                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1613                                                  rx->seqno_idx, &(rx->skb));
1614                 if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP &&
1615                     ieee80211_has_protected(fc)) {
1616                         int queue = rx->security_idx;
1617                         /* Store CCMP PN so that we can verify that the next
1618                          * fragment has a sequential PN value. */
1619                         entry->ccmp = 1;
1620                         memcpy(entry->last_pn,
1621                                rx->key->u.ccmp.rx_pn[queue],
1622                                CCMP_PN_LEN);
1623                 }
1624                 return RX_QUEUED;
1625         }
1626
1627         /* This is a fragment for a frame that should already be pending in
1628          * fragment cache. Add this fragment to the end of the pending entry.
1629          */
1630         entry = ieee80211_reassemble_find(rx->sdata, frag, seq,
1631                                           rx->seqno_idx, hdr);
1632         if (!entry) {
1633                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1634                 return RX_DROP_MONITOR;
1635         }
1636
1637         /* Verify that MPDUs within one MSDU have sequential PN values.
1638          * (IEEE 802.11i, 8.3.3.4.5) */
1639         if (entry->ccmp) {
1640                 int i;
1641                 u8 pn[CCMP_PN_LEN], *rpn;
1642                 int queue;
1643                 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP)
1644                         return RX_DROP_UNUSABLE;
1645                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1646                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1647                         pn[i]++;
1648                         if (pn[i])
1649                                 break;
1650                 }
1651                 queue = rx->security_idx;
1652                 rpn = rx->key->u.ccmp.rx_pn[queue];
1653                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1654                         return RX_DROP_UNUSABLE;
1655                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1656         }
1657
1658         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1659         __skb_queue_tail(&entry->skb_list, rx->skb);
1660         entry->last_frag = frag;
1661         entry->extra_len += rx->skb->len;
1662         if (ieee80211_has_morefrags(fc)) {
1663                 rx->skb = NULL;
1664                 return RX_QUEUED;
1665         }
1666
1667         rx->skb = __skb_dequeue(&entry->skb_list);
1668         if (skb_tailroom(rx->skb) < entry->extra_len) {
1669                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1670                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1671                                               GFP_ATOMIC))) {
1672                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1673                         __skb_queue_purge(&entry->skb_list);
1674                         return RX_DROP_UNUSABLE;
1675                 }
1676         }
1677         while ((skb = __skb_dequeue(&entry->skb_list))) {
1678                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1679                 dev_kfree_skb(skb);
1680         }
1681
1682         /* Complete frame has been reassembled - process it now */
1683         status = IEEE80211_SKB_RXCB(rx->skb);
1684         status->rx_flags |= IEEE80211_RX_FRAGMENTED;
1685
1686  out:
1687         if (rx->sta)
1688                 rx->sta->rx_packets++;
1689         if (is_multicast_ether_addr(hdr->addr1))
1690                 rx->local->dot11MulticastReceivedFrameCount++;
1691         else
1692                 ieee80211_led_rx(rx->local);
1693         return RX_CONTINUE;
1694 }
1695
1696 static int ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1697 {
1698         if (unlikely(!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_AUTHORIZED)))
1699                 return -EACCES;
1700
1701         return 0;
1702 }
1703
1704 static int ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1705 {
1706         struct sk_buff *skb = rx->skb;
1707         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1708
1709         /*
1710          * Pass through unencrypted frames if the hardware has
1711          * decrypted them already.
1712          */
1713         if (status->flag & RX_FLAG_DECRYPTED)
1714                 return 0;
1715
1716         /* Drop unencrypted frames if key is set. */
1717         if (unlikely(!ieee80211_has_protected(fc) &&
1718                      !ieee80211_is_nullfunc(fc) &&
1719                      ieee80211_is_data(fc) &&
1720                      (rx->key || rx->sdata->drop_unencrypted)))
1721                 return -EACCES;
1722
1723         return 0;
1724 }
1725
1726 static int ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1727 {
1728         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1729         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1730         __le16 fc = hdr->frame_control;
1731
1732         /*
1733          * Pass through unencrypted frames if the hardware has
1734          * decrypted them already.
1735          */
1736         if (status->flag & RX_FLAG_DECRYPTED)
1737                 return 0;
1738
1739         if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) {
1740                 if (unlikely(!ieee80211_has_protected(fc) &&
1741                              ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1742                              rx->key)) {
1743                         if (ieee80211_is_deauth(fc))
1744                                 cfg80211_send_unprot_deauth(rx->sdata->dev,
1745                                                             rx->skb->data,
1746                                                             rx->skb->len);
1747                         else if (ieee80211_is_disassoc(fc))
1748                                 cfg80211_send_unprot_disassoc(rx->sdata->dev,
1749                                                               rx->skb->data,
1750                                                               rx->skb->len);
1751                         return -EACCES;
1752                 }
1753                 /* BIP does not use Protected field, so need to check MMIE */
1754                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1755                              ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
1756                         if (ieee80211_is_deauth(fc))
1757                                 cfg80211_send_unprot_deauth(rx->sdata->dev,
1758                                                             rx->skb->data,
1759                                                             rx->skb->len);
1760                         else if (ieee80211_is_disassoc(fc))
1761                                 cfg80211_send_unprot_disassoc(rx->sdata->dev,
1762                                                               rx->skb->data,
1763                                                               rx->skb->len);
1764                         return -EACCES;
1765                 }
1766                 /*
1767                  * When using MFP, Action frames are not allowed prior to
1768                  * having configured keys.
1769                  */
1770                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1771                              ieee80211_is_robust_mgmt_frame(
1772                                      (struct ieee80211_hdr *) rx->skb->data)))
1773                         return -EACCES;
1774         }
1775
1776         return 0;
1777 }
1778
1779 static int
1780 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx, bool *port_control)
1781 {
1782         struct ieee80211_sub_if_data *sdata = rx->sdata;
1783         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1784         bool check_port_control = false;
1785         struct ethhdr *ehdr;
1786         int ret;
1787
1788         *port_control = false;
1789         if (ieee80211_has_a4(hdr->frame_control) &&
1790             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1791                 return -1;
1792
1793         if (sdata->vif.type == NL80211_IFTYPE_STATION &&
1794             !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) {
1795
1796                 if (!sdata->u.mgd.use_4addr)
1797                         return -1;
1798                 else
1799                         check_port_control = true;
1800         }
1801
1802         if (is_multicast_ether_addr(hdr->addr1) &&
1803             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta)
1804                 return -1;
1805
1806         ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1807         if (ret < 0)
1808                 return ret;
1809
1810         ehdr = (struct ethhdr *) rx->skb->data;
1811         if (ehdr->h_proto == rx->sdata->control_port_protocol)
1812                 *port_control = true;
1813         else if (check_port_control)
1814                 return -1;
1815
1816         return 0;
1817 }
1818
1819 /*
1820  * requires that rx->skb is a frame with ethernet header
1821  */
1822 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1823 {
1824         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1825                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1826         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1827
1828         /*
1829          * Allow EAPOL frames to us/the PAE group address regardless
1830          * of whether the frame was encrypted or not.
1831          */
1832         if (ehdr->h_proto == rx->sdata->control_port_protocol &&
1833             (ether_addr_equal(ehdr->h_dest, rx->sdata->vif.addr) ||
1834              ether_addr_equal(ehdr->h_dest, pae_group_addr)))
1835                 return true;
1836
1837         if (ieee80211_802_1x_port_control(rx) ||
1838             ieee80211_drop_unencrypted(rx, fc))
1839                 return false;
1840
1841         return true;
1842 }
1843
1844 /*
1845  * requires that rx->skb is a frame with ethernet header
1846  */
1847 static void
1848 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1849 {
1850         struct ieee80211_sub_if_data *sdata = rx->sdata;
1851         struct net_device *dev = sdata->dev;
1852         struct sk_buff *skb, *xmit_skb;
1853         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1854         struct sta_info *dsta;
1855         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1856
1857         skb = rx->skb;
1858         xmit_skb = NULL;
1859
1860         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1861              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1862             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1863             (status->rx_flags & IEEE80211_RX_RA_MATCH) &&
1864             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1865                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1866                         /*
1867                          * send multicast frames both to higher layers in
1868                          * local net stack and back to the wireless medium
1869                          */
1870                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1871                         if (!xmit_skb)
1872                                 net_info_ratelimited("%s: failed to clone multicast frame\n",
1873                                                     dev->name);
1874                 } else {
1875                         dsta = sta_info_get(sdata, skb->data);
1876                         if (dsta) {
1877                                 /*
1878                                  * The destination station is associated to
1879                                  * this AP (in this VLAN), so send the frame
1880                                  * directly to it and do not pass it to local
1881                                  * net stack.
1882                                  */
1883                                 xmit_skb = skb;
1884                                 skb = NULL;
1885                         }
1886                 }
1887         }
1888
1889         if (skb) {
1890                 int align __maybe_unused;
1891
1892 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1893                 /*
1894                  * 'align' will only take the values 0 or 2 here
1895                  * since all frames are required to be aligned
1896                  * to 2-byte boundaries when being passed to
1897                  * mac80211. That also explains the __skb_push()
1898                  * below.
1899                  */
1900                 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1901                 if (align) {
1902                         if (WARN_ON(skb_headroom(skb) < 3)) {
1903                                 dev_kfree_skb(skb);
1904                                 skb = NULL;
1905                         } else {
1906                                 u8 *data = skb->data;
1907                                 size_t len = skb_headlen(skb);
1908                                 skb->data -= align;
1909                                 memmove(skb->data, data, len);
1910                                 skb_set_tail_pointer(skb, len);
1911                         }
1912                 }
1913 #endif
1914
1915                 if (skb) {
1916                         /* deliver to local stack */
1917                         skb->protocol = eth_type_trans(skb, dev);
1918                         memset(skb->cb, 0, sizeof(skb->cb));
1919                         netif_receive_skb(skb);
1920                 }
1921         }
1922
1923         if (xmit_skb) {
1924                 /*
1925                  * Send to wireless media and increase priority by 256 to
1926                  * keep the received priority instead of reclassifying
1927                  * the frame (see cfg80211_classify8021d).
1928                  */
1929                 xmit_skb->priority += 256;
1930                 xmit_skb->protocol = htons(ETH_P_802_3);
1931                 skb_reset_network_header(xmit_skb);
1932                 skb_reset_mac_header(xmit_skb);
1933                 dev_queue_xmit(xmit_skb);
1934         }
1935 }
1936
1937 static ieee80211_rx_result debug_noinline
1938 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1939 {
1940         struct net_device *dev = rx->sdata->dev;
1941         struct sk_buff *skb = rx->skb;
1942         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1943         __le16 fc = hdr->frame_control;
1944         struct sk_buff_head frame_list;
1945         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1946
1947         if (unlikely(!ieee80211_is_data(fc)))
1948                 return RX_CONTINUE;
1949
1950         if (unlikely(!ieee80211_is_data_present(fc)))
1951                 return RX_DROP_MONITOR;
1952
1953         if (!(status->rx_flags & IEEE80211_RX_AMSDU))
1954                 return RX_CONTINUE;
1955
1956         if (ieee80211_has_a4(hdr->frame_control) &&
1957             rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1958             !rx->sdata->u.vlan.sta)
1959                 return RX_DROP_UNUSABLE;
1960
1961         if (is_multicast_ether_addr(hdr->addr1) &&
1962             ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1963               rx->sdata->u.vlan.sta) ||
1964              (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1965               rx->sdata->u.mgd.use_4addr)))
1966                 return RX_DROP_UNUSABLE;
1967
1968         skb->dev = dev;
1969         __skb_queue_head_init(&frame_list);
1970
1971         if (skb_linearize(skb))
1972                 return RX_DROP_UNUSABLE;
1973
1974         ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1975                                  rx->sdata->vif.type,
1976                                  rx->local->hw.extra_tx_headroom, true);
1977
1978         while (!skb_queue_empty(&frame_list)) {
1979                 rx->skb = __skb_dequeue(&frame_list);
1980
1981                 if (!ieee80211_frame_allowed(rx, fc)) {
1982                         dev_kfree_skb(rx->skb);
1983                         continue;
1984                 }
1985                 dev->stats.rx_packets++;
1986                 dev->stats.rx_bytes += rx->skb->len;
1987
1988                 ieee80211_deliver_skb(rx);
1989         }
1990
1991         return RX_QUEUED;
1992 }
1993
1994 #ifdef CONFIG_MAC80211_MESH
1995 static ieee80211_rx_result
1996 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1997 {
1998         struct ieee80211_hdr *fwd_hdr, *hdr;
1999         struct ieee80211_tx_info *info;
2000         struct ieee80211s_hdr *mesh_hdr;
2001         struct sk_buff *skb = rx->skb, *fwd_skb;
2002         struct ieee80211_local *local = rx->local;
2003         struct ieee80211_sub_if_data *sdata = rx->sdata;
2004         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2005         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
2006         __le16 reason = cpu_to_le16(WLAN_REASON_MESH_PATH_NOFORWARD);
2007         u16 q, hdrlen;
2008
2009         hdr = (struct ieee80211_hdr *) skb->data;
2010         hdrlen = ieee80211_hdrlen(hdr->frame_control);
2011
2012         /* make sure fixed part of mesh header is there, also checks skb len */
2013         if (!pskb_may_pull(rx->skb, hdrlen + 6))
2014                 return RX_DROP_MONITOR;
2015
2016         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2017
2018         /* make sure full mesh header is there, also checks skb len */
2019         if (!pskb_may_pull(rx->skb,
2020                            hdrlen + ieee80211_get_mesh_hdrlen(mesh_hdr)))
2021                 return RX_DROP_MONITOR;
2022
2023         /* reload pointers */
2024         hdr = (struct ieee80211_hdr *) skb->data;
2025         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2026
2027         /* frame is in RMC, don't forward */
2028         if (ieee80211_is_data(hdr->frame_control) &&
2029             is_multicast_ether_addr(hdr->addr1) &&
2030             mesh_rmc_check(rx->sdata, hdr->addr3, mesh_hdr))
2031                 return RX_DROP_MONITOR;
2032
2033         if (!ieee80211_is_data(hdr->frame_control) ||
2034             !(status->rx_flags & IEEE80211_RX_RA_MATCH))
2035                 return RX_CONTINUE;
2036
2037         if (!mesh_hdr->ttl)
2038                 return RX_DROP_MONITOR;
2039
2040         if (mesh_hdr->flags & MESH_FLAGS_AE) {
2041                 struct mesh_path *mppath;
2042                 char *proxied_addr;
2043                 char *mpp_addr;
2044
2045                 if (is_multicast_ether_addr(hdr->addr1)) {
2046                         mpp_addr = hdr->addr3;
2047                         proxied_addr = mesh_hdr->eaddr1;
2048                 } else if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6) {
2049                         /* has_a4 already checked in ieee80211_rx_mesh_check */
2050                         mpp_addr = hdr->addr4;
2051                         proxied_addr = mesh_hdr->eaddr2;
2052                 } else {
2053                         return RX_DROP_MONITOR;
2054                 }
2055
2056                 rcu_read_lock();
2057                 mppath = mpp_path_lookup(sdata, proxied_addr);
2058                 if (!mppath) {
2059                         mpp_path_add(sdata, proxied_addr, mpp_addr);
2060                 } else {
2061                         spin_lock_bh(&mppath->state_lock);
2062                         if (!ether_addr_equal(mppath->mpp, mpp_addr))
2063                                 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
2064                         spin_unlock_bh(&mppath->state_lock);
2065                 }
2066                 rcu_read_unlock();
2067         }
2068
2069         /* Frame has reached destination.  Don't forward */
2070         if (!is_multicast_ether_addr(hdr->addr1) &&
2071             ether_addr_equal(sdata->vif.addr, hdr->addr3))
2072                 return RX_CONTINUE;
2073
2074         q = ieee80211_select_queue_80211(sdata, skb, hdr);
2075         if (ieee80211_queue_stopped(&local->hw, q)) {
2076                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion);
2077                 return RX_DROP_MONITOR;
2078         }
2079         skb_set_queue_mapping(skb, q);
2080
2081         if (!--mesh_hdr->ttl) {
2082                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
2083                 goto out;
2084         }
2085
2086         if (!ifmsh->mshcfg.dot11MeshForwarding)
2087                 goto out;
2088
2089         fwd_skb = skb_copy(skb, GFP_ATOMIC);
2090         if (!fwd_skb) {
2091                 net_info_ratelimited("%s: failed to clone mesh frame\n",
2092                                     sdata->name);
2093                 goto out;
2094         }
2095
2096         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
2097         info = IEEE80211_SKB_CB(fwd_skb);
2098         memset(info, 0, sizeof(*info));
2099         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
2100         info->control.vif = &rx->sdata->vif;
2101         info->control.jiffies = jiffies;
2102         if (is_multicast_ether_addr(fwd_hdr->addr1)) {
2103                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_mcast);
2104                 memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
2105                 /* update power mode indication when forwarding */
2106                 ieee80211_mps_set_frame_flags(sdata, NULL, fwd_hdr);
2107         } else if (!mesh_nexthop_lookup(sdata, fwd_skb)) {
2108                 /* mesh power mode flags updated in mesh_nexthop_lookup */
2109                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_unicast);
2110         } else {
2111                 /* unable to resolve next hop */
2112                 mesh_path_error_tx(sdata, ifmsh->mshcfg.element_ttl,
2113                                    fwd_hdr->addr3, 0, reason, fwd_hdr->addr2);
2114                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_no_route);
2115                 kfree_skb(fwd_skb);
2116                 return RX_DROP_MONITOR;
2117         }
2118
2119         IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_frames);
2120         ieee80211_add_pending_skb(local, fwd_skb);
2121  out:
2122         if (is_multicast_ether_addr(hdr->addr1) ||
2123             sdata->dev->flags & IFF_PROMISC)
2124                 return RX_CONTINUE;
2125         else
2126                 return RX_DROP_MONITOR;
2127 }
2128 #endif
2129
2130 static ieee80211_rx_result debug_noinline
2131 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
2132 {
2133         struct ieee80211_sub_if_data *sdata = rx->sdata;
2134         struct ieee80211_local *local = rx->local;
2135         struct net_device *dev = sdata->dev;
2136         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2137         __le16 fc = hdr->frame_control;
2138         bool port_control;
2139         int err;
2140
2141         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
2142                 return RX_CONTINUE;
2143
2144         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
2145                 return RX_DROP_MONITOR;
2146
2147         /*
2148          * Send unexpected-4addr-frame event to hostapd. For older versions,
2149          * also drop the frame to cooked monitor interfaces.
2150          */
2151         if (ieee80211_has_a4(hdr->frame_control) &&
2152             sdata->vif.type == NL80211_IFTYPE_AP) {
2153                 if (rx->sta &&
2154                     !test_and_set_sta_flag(rx->sta, WLAN_STA_4ADDR_EVENT))
2155                         cfg80211_rx_unexpected_4addr_frame(
2156                                 rx->sdata->dev, rx->sta->sta.addr, GFP_ATOMIC);
2157                 return RX_DROP_MONITOR;
2158         }
2159
2160         err = __ieee80211_data_to_8023(rx, &port_control);
2161         if (unlikely(err))
2162                 return RX_DROP_UNUSABLE;
2163
2164         if (!ieee80211_frame_allowed(rx, fc))
2165                 return RX_DROP_MONITOR;
2166
2167         if (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
2168             unlikely(port_control) && sdata->bss) {
2169                 sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
2170                                      u.ap);
2171                 dev = sdata->dev;
2172                 rx->sdata = sdata;
2173         }
2174
2175         rx->skb->dev = dev;
2176
2177         dev->stats.rx_packets++;
2178         dev->stats.rx_bytes += rx->skb->len;
2179
2180         if (local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
2181             !is_multicast_ether_addr(
2182                     ((struct ethhdr *)rx->skb->data)->h_dest) &&
2183             (!local->scanning &&
2184              !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state))) {
2185                         mod_timer(&local->dynamic_ps_timer, jiffies +
2186                          msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
2187         }
2188
2189         ieee80211_deliver_skb(rx);
2190
2191         return RX_QUEUED;
2192 }
2193
2194 static ieee80211_rx_result debug_noinline
2195 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
2196 {
2197         struct sk_buff *skb = rx->skb;
2198         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
2199         struct tid_ampdu_rx *tid_agg_rx;
2200         u16 start_seq_num;
2201         u16 tid;
2202
2203         if (likely(!ieee80211_is_ctl(bar->frame_control)))
2204                 return RX_CONTINUE;
2205
2206         if (ieee80211_is_back_req(bar->frame_control)) {
2207                 struct {
2208                         __le16 control, start_seq_num;
2209                 } __packed bar_data;
2210
2211                 if (!rx->sta)
2212                         return RX_DROP_MONITOR;
2213
2214                 if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
2215                                   &bar_data, sizeof(bar_data)))
2216                         return RX_DROP_MONITOR;
2217
2218                 tid = le16_to_cpu(bar_data.control) >> 12;
2219
2220                 tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
2221                 if (!tid_agg_rx)
2222                         return RX_DROP_MONITOR;
2223
2224                 start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
2225
2226                 /* reset session timer */
2227                 if (tid_agg_rx->timeout)
2228                         mod_timer(&tid_agg_rx->session_timer,
2229                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
2230
2231                 spin_lock(&tid_agg_rx->reorder_lock);
2232                 /* release stored frames up to start of BAR */
2233                 ieee80211_release_reorder_frames(rx->sdata, tid_agg_rx,
2234                                                  start_seq_num, frames);
2235                 spin_unlock(&tid_agg_rx->reorder_lock);
2236
2237                 kfree_skb(skb);
2238                 return RX_QUEUED;
2239         }
2240
2241         /*
2242          * After this point, we only want management frames,
2243          * so we can drop all remaining control frames to
2244          * cooked monitor interfaces.
2245          */
2246         return RX_DROP_MONITOR;
2247 }
2248
2249 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
2250                                            struct ieee80211_mgmt *mgmt,
2251                                            size_t len)
2252 {
2253         struct ieee80211_local *local = sdata->local;
2254         struct sk_buff *skb;
2255         struct ieee80211_mgmt *resp;
2256
2257         if (!ether_addr_equal(mgmt->da, sdata->vif.addr)) {
2258                 /* Not to own unicast address */
2259                 return;
2260         }
2261
2262         if (!ether_addr_equal(mgmt->sa, sdata->u.mgd.bssid) ||
2263             !ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid)) {
2264                 /* Not from the current AP or not associated yet. */
2265                 return;
2266         }
2267
2268         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
2269                 /* Too short SA Query request frame */
2270                 return;
2271         }
2272
2273         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
2274         if (skb == NULL)
2275                 return;
2276
2277         skb_reserve(skb, local->hw.extra_tx_headroom);
2278         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
2279         memset(resp, 0, 24);
2280         memcpy(resp->da, mgmt->sa, ETH_ALEN);
2281         memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
2282         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
2283         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2284                                           IEEE80211_STYPE_ACTION);
2285         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
2286         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
2287         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
2288         memcpy(resp->u.action.u.sa_query.trans_id,
2289                mgmt->u.action.u.sa_query.trans_id,
2290                WLAN_SA_QUERY_TR_ID_LEN);
2291
2292         ieee80211_tx_skb(sdata, skb);
2293 }
2294
2295 static ieee80211_rx_result debug_noinline
2296 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
2297 {
2298         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2299         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2300
2301         /*
2302          * From here on, look only at management frames.
2303          * Data and control frames are already handled,
2304          * and unknown (reserved) frames are useless.
2305          */
2306         if (rx->skb->len < 24)
2307                 return RX_DROP_MONITOR;
2308
2309         if (!ieee80211_is_mgmt(mgmt->frame_control))
2310                 return RX_DROP_MONITOR;
2311
2312         if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
2313             ieee80211_is_beacon(mgmt->frame_control) &&
2314             !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) {
2315                 int sig = 0;
2316
2317                 if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2318                         sig = status->signal;
2319
2320                 cfg80211_report_obss_beacon(rx->local->hw.wiphy,
2321                                             rx->skb->data, rx->skb->len,
2322                                             status->freq, sig);
2323                 rx->flags |= IEEE80211_RX_BEACON_REPORTED;
2324         }
2325
2326         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2327                 return RX_DROP_MONITOR;
2328
2329         if (ieee80211_drop_unencrypted_mgmt(rx))
2330                 return RX_DROP_UNUSABLE;
2331
2332         return RX_CONTINUE;
2333 }
2334
2335 static ieee80211_rx_result debug_noinline
2336 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2337 {
2338         struct ieee80211_local *local = rx->local;
2339         struct ieee80211_sub_if_data *sdata = rx->sdata;
2340         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2341         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2342         int len = rx->skb->len;
2343
2344         if (!ieee80211_is_action(mgmt->frame_control))
2345                 return RX_CONTINUE;
2346
2347         /* drop too small frames */
2348         if (len < IEEE80211_MIN_ACTION_SIZE)
2349                 return RX_DROP_UNUSABLE;
2350
2351         if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC &&
2352             mgmt->u.action.category != WLAN_CATEGORY_SELF_PROTECTED)
2353                 return RX_DROP_UNUSABLE;
2354
2355         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2356                 return RX_DROP_UNUSABLE;
2357
2358         switch (mgmt->u.action.category) {
2359         case WLAN_CATEGORY_HT:
2360                 /* reject HT action frames from stations not supporting HT */
2361                 if (!rx->sta->sta.ht_cap.ht_supported)
2362                         goto invalid;
2363
2364                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2365                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2366                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2367                     sdata->vif.type != NL80211_IFTYPE_AP &&
2368                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2369                         break;
2370
2371                 /* verify action & smps_control/chanwidth are present */
2372                 if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2373                         goto invalid;
2374
2375                 switch (mgmt->u.action.u.ht_smps.action) {
2376                 case WLAN_HT_ACTION_SMPS: {
2377                         struct ieee80211_supported_band *sband;
2378                         enum ieee80211_smps_mode smps_mode;
2379
2380                         /* convert to HT capability */
2381                         switch (mgmt->u.action.u.ht_smps.smps_control) {
2382                         case WLAN_HT_SMPS_CONTROL_DISABLED:
2383                                 smps_mode = IEEE80211_SMPS_OFF;
2384                                 break;
2385                         case WLAN_HT_SMPS_CONTROL_STATIC:
2386                                 smps_mode = IEEE80211_SMPS_STATIC;
2387                                 break;
2388                         case WLAN_HT_SMPS_CONTROL_DYNAMIC:
2389                                 smps_mode = IEEE80211_SMPS_DYNAMIC;
2390                                 break;
2391                         default:
2392                                 goto invalid;
2393                         }
2394
2395                         /* if no change do nothing */
2396                         if (rx->sta->sta.smps_mode == smps_mode)
2397                                 goto handled;
2398                         rx->sta->sta.smps_mode = smps_mode;
2399
2400                         sband = rx->local->hw.wiphy->bands[status->band];
2401
2402                         rate_control_rate_update(local, sband, rx->sta,
2403                                                  IEEE80211_RC_SMPS_CHANGED);
2404                         goto handled;
2405                 }
2406                 case WLAN_HT_ACTION_NOTIFY_CHANWIDTH: {
2407                         struct ieee80211_supported_band *sband;
2408                         u8 chanwidth = mgmt->u.action.u.ht_notify_cw.chanwidth;
2409                         enum ieee80211_sta_rx_bandwidth new_bw;
2410
2411                         /* If it doesn't support 40 MHz it can't change ... */
2412                         if (!(rx->sta->sta.ht_cap.cap &
2413                                         IEEE80211_HT_CAP_SUP_WIDTH_20_40))
2414                                 goto handled;
2415
2416                         if (chanwidth == IEEE80211_HT_CHANWIDTH_20MHZ)
2417                                 new_bw = IEEE80211_STA_RX_BW_20;
2418                         else
2419                                 new_bw = ieee80211_sta_cur_vht_bw(rx->sta);
2420
2421                         if (rx->sta->sta.bandwidth == new_bw)
2422                                 goto handled;
2423
2424                         sband = rx->local->hw.wiphy->bands[status->band];
2425
2426                         rate_control_rate_update(local, sband, rx->sta,
2427                                                  IEEE80211_RC_BW_CHANGED);
2428                         goto handled;
2429                 }
2430                 default:
2431                         goto invalid;
2432                 }
2433
2434                 break;
2435         case WLAN_CATEGORY_VHT:
2436                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2437                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2438                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2439                     sdata->vif.type != NL80211_IFTYPE_AP &&
2440                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2441                         break;
2442
2443                 /* verify action code is present */
2444                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2445                         goto invalid;
2446
2447                 switch (mgmt->u.action.u.vht_opmode_notif.action_code) {
2448                 case WLAN_VHT_ACTION_OPMODE_NOTIF: {
2449                         u8 opmode;
2450
2451                         /* verify opmode is present */
2452                         if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2453                                 goto invalid;
2454
2455                         opmode = mgmt->u.action.u.vht_opmode_notif.operating_mode;
2456
2457                         ieee80211_vht_handle_opmode(rx->sdata, rx->sta,
2458                                                     opmode, status->band,
2459                                                     false);
2460                         goto handled;
2461                 }
2462                 default:
2463                         break;
2464                 }
2465                 break;
2466         case WLAN_CATEGORY_BACK:
2467                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2468                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2469                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2470                     sdata->vif.type != NL80211_IFTYPE_AP &&
2471                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2472                         break;
2473
2474                 /* verify action_code is present */
2475                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2476                         break;
2477
2478                 switch (mgmt->u.action.u.addba_req.action_code) {
2479                 case WLAN_ACTION_ADDBA_REQ:
2480                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2481                                    sizeof(mgmt->u.action.u.addba_req)))
2482                                 goto invalid;
2483                         break;
2484                 case WLAN_ACTION_ADDBA_RESP:
2485                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2486                                    sizeof(mgmt->u.action.u.addba_resp)))
2487                                 goto invalid;
2488                         break;
2489                 case WLAN_ACTION_DELBA:
2490                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2491                                    sizeof(mgmt->u.action.u.delba)))
2492                                 goto invalid;
2493                         break;
2494                 default:
2495                         goto invalid;
2496                 }
2497
2498                 goto queue;
2499         case WLAN_CATEGORY_SPECTRUM_MGMT:
2500                 if (status->band != IEEE80211_BAND_5GHZ)
2501                         break;
2502
2503                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2504                         break;
2505
2506                 /* verify action_code is present */
2507                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2508                         break;
2509
2510                 switch (mgmt->u.action.u.measurement.action_code) {
2511                 case WLAN_ACTION_SPCT_MSR_REQ:
2512                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2513                                    sizeof(mgmt->u.action.u.measurement)))
2514                                 break;
2515                         ieee80211_process_measurement_req(sdata, mgmt, len);
2516                         goto handled;
2517                 case WLAN_ACTION_SPCT_CHL_SWITCH:
2518                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2519                                    sizeof(mgmt->u.action.u.chan_switch)))
2520                                 break;
2521
2522                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2523                                 break;
2524
2525                         if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
2526                                 break;
2527
2528                         goto queue;
2529                 }
2530                 break;
2531         case WLAN_CATEGORY_SA_QUERY:
2532                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2533                            sizeof(mgmt->u.action.u.sa_query)))
2534                         break;
2535
2536                 switch (mgmt->u.action.u.sa_query.action) {
2537                 case WLAN_ACTION_SA_QUERY_REQUEST:
2538                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2539                                 break;
2540                         ieee80211_process_sa_query_req(sdata, mgmt, len);
2541                         goto handled;
2542                 }
2543                 break;
2544         case WLAN_CATEGORY_SELF_PROTECTED:
2545                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2546                            sizeof(mgmt->u.action.u.self_prot.action_code)))
2547                         break;
2548
2549                 switch (mgmt->u.action.u.self_prot.action_code) {
2550                 case WLAN_SP_MESH_PEERING_OPEN:
2551                 case WLAN_SP_MESH_PEERING_CLOSE:
2552                 case WLAN_SP_MESH_PEERING_CONFIRM:
2553                         if (!ieee80211_vif_is_mesh(&sdata->vif))
2554                                 goto invalid;
2555                         if (sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE)
2556                                 /* userspace handles this frame */
2557                                 break;
2558                         goto queue;
2559                 case WLAN_SP_MGK_INFORM:
2560                 case WLAN_SP_MGK_ACK:
2561                         if (!ieee80211_vif_is_mesh(&sdata->vif))
2562                                 goto invalid;
2563                         break;
2564                 }
2565                 break;
2566         case WLAN_CATEGORY_MESH_ACTION:
2567                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2568                            sizeof(mgmt->u.action.u.mesh_action.action_code)))
2569                         break;
2570
2571                 if (!ieee80211_vif_is_mesh(&sdata->vif))
2572                         break;
2573                 if (mesh_action_is_path_sel(mgmt) &&
2574                     !mesh_path_sel_is_hwmp(sdata))
2575                         break;
2576                 goto queue;
2577         }
2578
2579         return RX_CONTINUE;
2580
2581  invalid:
2582         status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
2583         /* will return in the next handlers */
2584         return RX_CONTINUE;
2585
2586  handled:
2587         if (rx->sta)
2588                 rx->sta->rx_packets++;
2589         dev_kfree_skb(rx->skb);
2590         return RX_QUEUED;
2591
2592  queue:
2593         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2594         skb_queue_tail(&sdata->skb_queue, rx->skb);
2595         ieee80211_queue_work(&local->hw, &sdata->work);
2596         if (rx->sta)
2597                 rx->sta->rx_packets++;
2598         return RX_QUEUED;
2599 }
2600
2601 static ieee80211_rx_result debug_noinline
2602 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
2603 {
2604         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2605         int sig = 0;
2606
2607         /* skip known-bad action frames and return them in the next handler */
2608         if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
2609                 return RX_CONTINUE;
2610
2611         /*
2612          * Getting here means the kernel doesn't know how to handle
2613          * it, but maybe userspace does ... include returned frames
2614          * so userspace can register for those to know whether ones
2615          * it transmitted were processed or returned.
2616          */
2617
2618         if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2619                 sig = status->signal;
2620
2621         if (cfg80211_rx_mgmt(&rx->sdata->wdev, status->freq, sig,
2622                              rx->skb->data, rx->skb->len,
2623                              GFP_ATOMIC)) {
2624                 if (rx->sta)
2625                         rx->sta->rx_packets++;
2626                 dev_kfree_skb(rx->skb);
2627                 return RX_QUEUED;
2628         }
2629
2630         return RX_CONTINUE;
2631 }
2632
2633 static ieee80211_rx_result debug_noinline
2634 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
2635 {
2636         struct ieee80211_local *local = rx->local;
2637         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2638         struct sk_buff *nskb;
2639         struct ieee80211_sub_if_data *sdata = rx->sdata;
2640         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2641
2642         if (!ieee80211_is_action(mgmt->frame_control))
2643                 return RX_CONTINUE;
2644
2645         /*
2646          * For AP mode, hostapd is responsible for handling any action
2647          * frames that we didn't handle, including returning unknown
2648          * ones. For all other modes we will return them to the sender,
2649          * setting the 0x80 bit in the action category, as required by
2650          * 802.11-2012 9.24.4.
2651          * Newer versions of hostapd shall also use the management frame
2652          * registration mechanisms, but older ones still use cooked
2653          * monitor interfaces so push all frames there.
2654          */
2655         if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
2656             (sdata->vif.type == NL80211_IFTYPE_AP ||
2657              sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
2658                 return RX_DROP_MONITOR;
2659
2660         if (is_multicast_ether_addr(mgmt->da))
2661                 return RX_DROP_MONITOR;
2662
2663         /* do not return rejected action frames */
2664         if (mgmt->u.action.category & 0x80)
2665                 return RX_DROP_UNUSABLE;
2666
2667         nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2668                                GFP_ATOMIC);
2669         if (nskb) {
2670                 struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
2671
2672                 nmgmt->u.action.category |= 0x80;
2673                 memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
2674                 memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2675
2676                 memset(nskb->cb, 0, sizeof(nskb->cb));
2677
2678                 ieee80211_tx_skb(rx->sdata, nskb);
2679         }
2680         dev_kfree_skb(rx->skb);
2681         return RX_QUEUED;
2682 }
2683
2684 static ieee80211_rx_result debug_noinline
2685 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2686 {
2687         struct ieee80211_sub_if_data *sdata = rx->sdata;
2688         struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2689         __le16 stype;
2690
2691         stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2692
2693         if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2694             sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2695             sdata->vif.type != NL80211_IFTYPE_STATION)
2696                 return RX_DROP_MONITOR;
2697
2698         switch (stype) {
2699         case cpu_to_le16(IEEE80211_STYPE_AUTH):
2700         case cpu_to_le16(IEEE80211_STYPE_BEACON):
2701         case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2702                 /* process for all: mesh, mlme, ibss */
2703                 break;
2704         case cpu_to_le16(IEEE80211_STYPE_ASSOC_RESP):
2705         case cpu_to_le16(IEEE80211_STYPE_REASSOC_RESP):
2706         case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2707         case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2708                 if (is_multicast_ether_addr(mgmt->da) &&
2709                     !is_broadcast_ether_addr(mgmt->da))
2710                         return RX_DROP_MONITOR;
2711
2712                 /* process only for station */
2713                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2714                         return RX_DROP_MONITOR;
2715                 break;
2716         case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2717                 /* process only for ibss and mesh */
2718                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2719                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT)
2720                         return RX_DROP_MONITOR;
2721                 break;
2722         default:
2723                 return RX_DROP_MONITOR;
2724         }
2725
2726         /* queue up frame and kick off work to process it */
2727         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2728         skb_queue_tail(&sdata->skb_queue, rx->skb);
2729         ieee80211_queue_work(&rx->local->hw, &sdata->work);
2730         if (rx->sta)
2731                 rx->sta->rx_packets++;
2732
2733         return RX_QUEUED;
2734 }
2735
2736 /* TODO: use IEEE80211_RX_FRAGMENTED */
2737 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2738                                         struct ieee80211_rate *rate)
2739 {
2740         struct ieee80211_sub_if_data *sdata;
2741         struct ieee80211_local *local = rx->local;
2742         struct sk_buff *skb = rx->skb, *skb2;
2743         struct net_device *prev_dev = NULL;
2744         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2745         int needed_headroom;
2746
2747         /*
2748          * If cooked monitor has been processed already, then
2749          * don't do it again. If not, set the flag.
2750          */
2751         if (rx->flags & IEEE80211_RX_CMNTR)
2752                 goto out_free_skb;
2753         rx->flags |= IEEE80211_RX_CMNTR;
2754
2755         /* If there are no cooked monitor interfaces, just free the SKB */
2756         if (!local->cooked_mntrs)
2757                 goto out_free_skb;
2758
2759         /* room for the radiotap header based on driver features */
2760         needed_headroom = ieee80211_rx_radiotap_space(local, status);
2761
2762         if (skb_headroom(skb) < needed_headroom &&
2763             pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC))
2764                 goto out_free_skb;
2765
2766         /* prepend radiotap information */
2767         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
2768                                          false);
2769
2770         skb_set_mac_header(skb, 0);
2771         skb->ip_summed = CHECKSUM_UNNECESSARY;
2772         skb->pkt_type = PACKET_OTHERHOST;
2773         skb->protocol = htons(ETH_P_802_2);
2774
2775         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2776                 if (!ieee80211_sdata_running(sdata))
2777                         continue;
2778
2779                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2780                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2781                         continue;
2782
2783                 if (prev_dev) {
2784                         skb2 = skb_clone(skb, GFP_ATOMIC);
2785                         if (skb2) {
2786                                 skb2->dev = prev_dev;
2787                                 netif_receive_skb(skb2);
2788                         }
2789                 }
2790
2791                 prev_dev = sdata->dev;
2792                 sdata->dev->stats.rx_packets++;
2793                 sdata->dev->stats.rx_bytes += skb->len;
2794         }
2795
2796         if (prev_dev) {
2797                 skb->dev = prev_dev;
2798                 netif_receive_skb(skb);
2799                 return;
2800         }
2801
2802  out_free_skb:
2803         dev_kfree_skb(skb);
2804 }
2805
2806 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
2807                                          ieee80211_rx_result res)
2808 {
2809         switch (res) {
2810         case RX_DROP_MONITOR:
2811                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2812                 if (rx->sta)
2813                         rx->sta->rx_dropped++;
2814                 /* fall through */
2815         case RX_CONTINUE: {
2816                 struct ieee80211_rate *rate = NULL;
2817                 struct ieee80211_supported_band *sband;
2818                 struct ieee80211_rx_status *status;
2819
2820                 status = IEEE80211_SKB_RXCB((rx->skb));
2821
2822                 sband = rx->local->hw.wiphy->bands[status->band];
2823                 if (!(status->flag & RX_FLAG_HT) &&
2824                     !(status->flag & RX_FLAG_VHT))
2825                         rate = &sband->bitrates[status->rate_idx];
2826
2827                 ieee80211_rx_cooked_monitor(rx, rate);
2828                 break;
2829                 }
2830         case RX_DROP_UNUSABLE:
2831                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2832                 if (rx->sta)
2833                         rx->sta->rx_dropped++;
2834                 dev_kfree_skb(rx->skb);
2835                 break;
2836         case RX_QUEUED:
2837                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
2838                 break;
2839         }
2840 }
2841
2842 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
2843                                   struct sk_buff_head *frames)
2844 {
2845         ieee80211_rx_result res = RX_DROP_MONITOR;
2846         struct sk_buff *skb;
2847
2848 #define CALL_RXH(rxh)                   \
2849         do {                            \
2850                 res = rxh(rx);          \
2851                 if (res != RX_CONTINUE) \
2852                         goto rxh_next;  \
2853         } while (0);
2854
2855         spin_lock_bh(&rx->local->rx_path_lock);
2856
2857         while ((skb = __skb_dequeue(frames))) {
2858                 /*
2859                  * all the other fields are valid across frames
2860                  * that belong to an aMPDU since they are on the
2861                  * same TID from the same station
2862                  */
2863                 rx->skb = skb;
2864
2865                 CALL_RXH(ieee80211_rx_h_decrypt)
2866                 CALL_RXH(ieee80211_rx_h_check_more_data)
2867                 CALL_RXH(ieee80211_rx_h_uapsd_and_pspoll)
2868                 CALL_RXH(ieee80211_rx_h_sta_process)
2869                 CALL_RXH(ieee80211_rx_h_defragment)
2870                 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2871                 /* must be after MMIC verify so header is counted in MPDU mic */
2872 #ifdef CONFIG_MAC80211_MESH
2873                 if (ieee80211_vif_is_mesh(&rx->sdata->vif))
2874                         CALL_RXH(ieee80211_rx_h_mesh_fwding);
2875 #endif
2876                 CALL_RXH(ieee80211_rx_h_amsdu)
2877                 CALL_RXH(ieee80211_rx_h_data)
2878
2879                 /* special treatment -- needs the queue */
2880                 res = ieee80211_rx_h_ctrl(rx, frames);
2881                 if (res != RX_CONTINUE)
2882                         goto rxh_next;
2883
2884                 CALL_RXH(ieee80211_rx_h_mgmt_check)
2885                 CALL_RXH(ieee80211_rx_h_action)
2886                 CALL_RXH(ieee80211_rx_h_userspace_mgmt)
2887                 CALL_RXH(ieee80211_rx_h_action_return)
2888                 CALL_RXH(ieee80211_rx_h_mgmt)
2889
2890  rxh_next:
2891                 ieee80211_rx_handlers_result(rx, res);
2892
2893 #undef CALL_RXH
2894         }
2895
2896         spin_unlock_bh(&rx->local->rx_path_lock);
2897 }
2898
2899 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
2900 {
2901         struct sk_buff_head reorder_release;
2902         ieee80211_rx_result res = RX_DROP_MONITOR;
2903
2904         __skb_queue_head_init(&reorder_release);
2905
2906 #define CALL_RXH(rxh)                   \
2907         do {                            \
2908                 res = rxh(rx);          \
2909                 if (res != RX_CONTINUE) \
2910                         goto rxh_next;  \
2911         } while (0);
2912
2913         CALL_RXH(ieee80211_rx_h_check)
2914
2915         ieee80211_rx_reorder_ampdu(rx, &reorder_release);
2916
2917         ieee80211_rx_handlers(rx, &reorder_release);
2918         return;
2919
2920  rxh_next:
2921         ieee80211_rx_handlers_result(rx, res);
2922
2923 #undef CALL_RXH
2924 }
2925
2926 /*
2927  * This function makes calls into the RX path, therefore
2928  * it has to be invoked under RCU read lock.
2929  */
2930 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
2931 {
2932         struct sk_buff_head frames;
2933         struct ieee80211_rx_data rx = {
2934                 .sta = sta,
2935                 .sdata = sta->sdata,
2936                 .local = sta->local,
2937                 /* This is OK -- must be QoS data frame */
2938                 .security_idx = tid,
2939                 .seqno_idx = tid,
2940                 .flags = 0,
2941         };
2942         struct tid_ampdu_rx *tid_agg_rx;
2943
2944         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
2945         if (!tid_agg_rx)
2946                 return;
2947
2948         __skb_queue_head_init(&frames);
2949
2950         spin_lock(&tid_agg_rx->reorder_lock);
2951         ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx, &frames);
2952         spin_unlock(&tid_agg_rx->reorder_lock);
2953
2954         ieee80211_rx_handlers(&rx, &frames);
2955 }
2956
2957 /* main receive path */
2958
2959 static int prepare_for_handlers(struct ieee80211_rx_data *rx,
2960                                 struct ieee80211_hdr *hdr)
2961 {
2962         struct ieee80211_sub_if_data *sdata = rx->sdata;
2963         struct sk_buff *skb = rx->skb;
2964         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2965         u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2966         int multicast = is_multicast_ether_addr(hdr->addr1);
2967
2968         switch (sdata->vif.type) {
2969         case NL80211_IFTYPE_STATION:
2970                 if (!bssid && !sdata->u.mgd.use_4addr)
2971                         return 0;
2972                 if (!multicast &&
2973                     !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
2974                         if (!(sdata->dev->flags & IFF_PROMISC) ||
2975                             sdata->u.mgd.use_4addr)
2976                                 return 0;
2977                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2978                 }
2979                 break;
2980         case NL80211_IFTYPE_ADHOC:
2981                 if (!bssid)
2982                         return 0;
2983                 if (ieee80211_is_beacon(hdr->frame_control)) {
2984                         return 1;
2985                 } else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
2986                         return 0;
2987                 } else if (!multicast &&
2988                            !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
2989                         if (!(sdata->dev->flags & IFF_PROMISC))
2990                                 return 0;
2991                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2992                 } else if (!rx->sta) {
2993                         int rate_idx;
2994                         if (status->flag & (RX_FLAG_HT | RX_FLAG_VHT))
2995                                 rate_idx = 0; /* TODO: HT/VHT rates */
2996                         else
2997                                 rate_idx = status->rate_idx;
2998                         ieee80211_ibss_rx_no_sta(sdata, bssid, hdr->addr2,
2999                                                  BIT(rate_idx));
3000                 }
3001                 break;
3002         case NL80211_IFTYPE_MESH_POINT:
3003                 if (!multicast &&
3004                     !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
3005                         if (!(sdata->dev->flags & IFF_PROMISC))
3006                                 return 0;
3007
3008                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3009                 }
3010                 break;
3011         case NL80211_IFTYPE_AP_VLAN:
3012         case NL80211_IFTYPE_AP:
3013                 if (!bssid) {
3014                         if (!ether_addr_equal(sdata->vif.addr, hdr->addr1))
3015                                 return 0;
3016                 } else if (!ieee80211_bssid_match(bssid, sdata->vif.addr)) {
3017                         /*
3018                          * Accept public action frames even when the
3019                          * BSSID doesn't match, this is used for P2P
3020                          * and location updates. Note that mac80211
3021                          * itself never looks at these frames.
3022                          */
3023                         if (ieee80211_is_public_action(hdr, skb->len))
3024                                 return 1;
3025                         if (!ieee80211_is_beacon(hdr->frame_control))
3026                                 return 0;
3027                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3028                 }
3029                 break;
3030         case NL80211_IFTYPE_WDS:
3031                 if (bssid || !ieee80211_is_data(hdr->frame_control))
3032                         return 0;
3033                 if (!ether_addr_equal(sdata->u.wds.remote_addr, hdr->addr2))
3034                         return 0;
3035                 break;
3036         case NL80211_IFTYPE_P2P_DEVICE:
3037                 if (!ieee80211_is_public_action(hdr, skb->len) &&
3038                     !ieee80211_is_probe_req(hdr->frame_control) &&
3039                     !ieee80211_is_probe_resp(hdr->frame_control) &&
3040                     !ieee80211_is_beacon(hdr->frame_control))
3041                         return 0;
3042                 if (!ether_addr_equal(sdata->vif.addr, hdr->addr1))
3043                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3044                 break;
3045         default:
3046                 /* should never get here */
3047                 WARN_ON_ONCE(1);
3048                 break;
3049         }
3050
3051         return 1;
3052 }
3053
3054 /*
3055  * This function returns whether or not the SKB
3056  * was destined for RX processing or not, which,
3057  * if consume is true, is equivalent to whether
3058  * or not the skb was consumed.
3059  */
3060 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
3061                                             struct sk_buff *skb, bool consume)
3062 {
3063         struct ieee80211_local *local = rx->local;
3064         struct ieee80211_sub_if_data *sdata = rx->sdata;
3065         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3066         struct ieee80211_hdr *hdr = (void *)skb->data;
3067         int prepares;
3068
3069         rx->skb = skb;
3070         status->rx_flags |= IEEE80211_RX_RA_MATCH;
3071         prepares = prepare_for_handlers(rx, hdr);
3072
3073         if (!prepares)
3074                 return false;
3075
3076         if (!consume) {
3077                 skb = skb_copy(skb, GFP_ATOMIC);
3078                 if (!skb) {
3079                         if (net_ratelimit())
3080                                 wiphy_debug(local->hw.wiphy,
3081                                         "failed to copy skb for %s\n",
3082                                         sdata->name);
3083                         return true;
3084                 }
3085
3086                 rx->skb = skb;
3087         }
3088
3089         ieee80211_invoke_rx_handlers(rx);
3090         return true;
3091 }
3092
3093 /*
3094  * This is the actual Rx frames handler. as it blongs to Rx path it must
3095  * be called with rcu_read_lock protection.
3096  */
3097 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
3098                                          struct sk_buff *skb)
3099 {
3100         struct ieee80211_local *local = hw_to_local(hw);
3101         struct ieee80211_sub_if_data *sdata;
3102         struct ieee80211_hdr *hdr;
3103         __le16 fc;
3104         struct ieee80211_rx_data rx;
3105         struct ieee80211_sub_if_data *prev;
3106         struct sta_info *sta, *tmp, *prev_sta;
3107         int err = 0;
3108
3109         fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
3110         memset(&rx, 0, sizeof(rx));
3111         rx.skb = skb;
3112         rx.local = local;
3113
3114         if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
3115                 local->dot11ReceivedFragmentCount++;
3116
3117         if (ieee80211_is_mgmt(fc)) {
3118                 /* drop frame if too short for header */
3119                 if (skb->len < ieee80211_hdrlen(fc))
3120                         err = -ENOBUFS;
3121                 else
3122                         err = skb_linearize(skb);
3123         } else {
3124                 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
3125         }
3126
3127         if (err) {
3128                 dev_kfree_skb(skb);
3129                 return;
3130         }
3131
3132         hdr = (struct ieee80211_hdr *)skb->data;
3133         ieee80211_parse_qos(&rx);
3134         ieee80211_verify_alignment(&rx);
3135
3136         if (unlikely(ieee80211_is_probe_resp(hdr->frame_control) ||
3137                      ieee80211_is_beacon(hdr->frame_control)))
3138                 ieee80211_scan_rx(local, skb);
3139
3140         if (ieee80211_is_data(fc)) {
3141                 prev_sta = NULL;
3142
3143                 for_each_sta_info(local, hdr->addr2, sta, tmp) {
3144                         if (!prev_sta) {
3145                                 prev_sta = sta;
3146                                 continue;
3147                         }
3148
3149                         rx.sta = prev_sta;
3150                         rx.sdata = prev_sta->sdata;
3151                         ieee80211_prepare_and_rx_handle(&rx, skb, false);
3152
3153                         prev_sta = sta;
3154                 }
3155
3156                 if (prev_sta) {
3157                         rx.sta = prev_sta;
3158                         rx.sdata = prev_sta->sdata;
3159
3160                         if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
3161                                 return;
3162                         goto out;
3163                 }
3164         }
3165
3166         prev = NULL;
3167
3168         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
3169                 if (!ieee80211_sdata_running(sdata))
3170                         continue;
3171
3172                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
3173                     sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
3174                         continue;
3175
3176                 /*
3177                  * frame is destined for this interface, but if it's
3178                  * not also for the previous one we handle that after
3179                  * the loop to avoid copying the SKB once too much
3180                  */
3181
3182                 if (!prev) {
3183                         prev = sdata;
3184                         continue;
3185                 }
3186
3187                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
3188                 rx.sdata = prev;
3189                 ieee80211_prepare_and_rx_handle(&rx, skb, false);
3190
3191                 prev = sdata;
3192         }
3193
3194         if (prev) {
3195                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
3196                 rx.sdata = prev;
3197
3198                 if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
3199                         return;
3200         }
3201
3202  out:
3203         dev_kfree_skb(skb);
3204 }
3205
3206 /*
3207  * This is the receive path handler. It is called by a low level driver when an
3208  * 802.11 MPDU is received from the hardware.
3209  */
3210 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
3211 {
3212         struct ieee80211_local *local = hw_to_local(hw);
3213         struct ieee80211_rate *rate = NULL;
3214         struct ieee80211_supported_band *sband;
3215         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3216
3217         WARN_ON_ONCE(softirq_count() == 0);
3218
3219         if (WARN_ON(status->band >= IEEE80211_NUM_BANDS))
3220                 goto drop;
3221
3222         sband = local->hw.wiphy->bands[status->band];
3223         if (WARN_ON(!sband))
3224                 goto drop;
3225
3226         /*
3227          * If we're suspending, it is possible although not too likely
3228          * that we'd be receiving frames after having already partially
3229          * quiesced the stack. We can't process such frames then since
3230          * that might, for example, cause stations to be added or other
3231          * driver callbacks be invoked.
3232          */
3233         if (unlikely(local->quiescing || local->suspended))
3234                 goto drop;
3235
3236         /* We might be during a HW reconfig, prevent Rx for the same reason */
3237         if (unlikely(local->in_reconfig))
3238                 goto drop;
3239
3240         /*
3241          * The same happens when we're not even started,
3242          * but that's worth a warning.
3243          */
3244         if (WARN_ON(!local->started))
3245                 goto drop;
3246
3247         if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
3248                 /*
3249                  * Validate the rate, unless a PLCP error means that
3250                  * we probably can't have a valid rate here anyway.
3251                  */
3252
3253                 if (status->flag & RX_FLAG_HT) {
3254                         /*
3255                          * rate_idx is MCS index, which can be [0-76]
3256                          * as documented on:
3257                          *
3258                          * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
3259                          *
3260                          * Anything else would be some sort of driver or
3261                          * hardware error. The driver should catch hardware
3262                          * errors.
3263                          */
3264                         if (WARN(status->rate_idx > 76,
3265                                  "Rate marked as an HT rate but passed "
3266                                  "status->rate_idx is not "
3267                                  "an MCS index [0-76]: %d (0x%02x)\n",
3268                                  status->rate_idx,
3269                                  status->rate_idx))
3270                                 goto drop;
3271                 } else if (status->flag & RX_FLAG_VHT) {
3272                         if (WARN_ONCE(status->rate_idx > 9 ||
3273                                       !status->vht_nss ||
3274                                       status->vht_nss > 8,
3275                                       "Rate marked as a VHT rate but data is invalid: MCS: %d, NSS: %d\n",
3276                                       status->rate_idx, status->vht_nss))
3277                                 goto drop;
3278                 } else {
3279                         if (WARN_ON(status->rate_idx >= sband->n_bitrates))
3280                                 goto drop;
3281                         rate = &sband->bitrates[status->rate_idx];
3282                 }
3283         }
3284
3285         status->rx_flags = 0;
3286
3287         /*
3288          * key references and virtual interfaces are protected using RCU
3289          * and this requires that we are in a read-side RCU section during
3290          * receive processing
3291          */
3292         rcu_read_lock();
3293
3294         /*
3295          * Frames with failed FCS/PLCP checksum are not returned,
3296          * all other frames are returned without radiotap header
3297          * if it was previously present.
3298          * Also, frames with less than 16 bytes are dropped.
3299          */
3300         skb = ieee80211_rx_monitor(local, skb, rate);
3301         if (!skb) {
3302                 rcu_read_unlock();
3303                 return;
3304         }
3305
3306         ieee80211_tpt_led_trig_rx(local,
3307                         ((struct ieee80211_hdr *)skb->data)->frame_control,
3308                         skb->len);
3309         __ieee80211_rx_handle_packet(hw, skb);
3310
3311         rcu_read_unlock();
3312
3313         return;
3314  drop:
3315         kfree_skb(skb);
3316 }
3317 EXPORT_SYMBOL(ieee80211_rx);
3318
3319 /* This is a version of the rx handler that can be called from hard irq
3320  * context. Post the skb on the queue and schedule the tasklet */
3321 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
3322 {
3323         struct ieee80211_local *local = hw_to_local(hw);
3324
3325         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
3326
3327         skb->pkt_type = IEEE80211_RX_MSG;
3328         skb_queue_tail(&local->skb_queue, skb);
3329         tasklet_schedule(&local->tasklet);
3330 }
3331 EXPORT_SYMBOL(ieee80211_rx_irqsafe);