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 static void ieee80211_release_reorder_frame(struct ieee80211_sub_if_data *sdata,
 652                                             struct tid_ampdu_rx *tid_agg_rx,
 653                                             int index,
 654                                             struct sk_buff_head *frames)
 655 {
 656         struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
 657         struct ieee80211_rx_status *status;
 658
 659         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 660
 661         if (!skb)
 662                 goto no_frame;
 663
 664         /* release the frame from the reorder ring buffer */
 665         tid_agg_rx->stored_mpdu_num--;
 666         tid_agg_rx->reorder_buf[index] = NULL;
 667         status = IEEE80211_SKB_RXCB(skb);
 668         status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE;
 669         __skb_queue_tail(frames, skb);
 670
 671 no_frame:
 672         tid_agg_rx->head_seq_num = ieee80211_sn_inc(tid_agg_rx->head_seq_num);
 673 }
 674
 675 static void ieee80211_release_reorder_frames(struct ieee80211_sub_if_data *sdata,
 676                                              struct tid_ampdu_rx *tid_agg_rx,
 677                                              u16 head_seq_num,
 678                                              struct sk_buff_head *frames)
 679 {
 680         int index;
 681
 682         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 683
 684         while (ieee80211_sn_less(tid_agg_rx->head_seq_num, head_seq_num)) {
 685                 index = ieee80211_sn_sub(tid_agg_rx->head_seq_num,
 686                                          tid_agg_rx->ssn) %
 687                                                         tid_agg_rx->buf_size;
 688                 ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
 689                                                 frames);
 690         }
 691 }
 692
 693 /*
 694  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
 695  * the skb was added to the buffer longer than this time ago, the earlier
 696  * frames that have not yet been received are assumed to be lost and the skb
 697  * can be released for processing. This may also release other skb's from the
 698  * reorder buffer if there are no additional gaps between the frames.
 699  *
 700  * Callers must hold tid_agg_rx->reorder_lock.
 701  */
 702 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
 703
 704 static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata,
 705                                           struct tid_ampdu_rx *tid_agg_rx,
 706                                           struct sk_buff_head *frames)
 707 {
 708         int index, j;
 709
 710         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 711
 712         /* release the buffer until next missing frame */
 713         index = ieee80211_sn_sub(tid_agg_rx->head_seq_num,
 714                                  tid_agg_rx->ssn) % tid_agg_rx->buf_size;
 715         if (!tid_agg_rx->reorder_buf[index] &&
 716             tid_agg_rx->stored_mpdu_num) {
 717                 /*
 718                  * No buffers ready to be released, but check whether any
 719                  * frames in the reorder buffer have timed out.
 720                  */
 721                 int skipped = 1;
 722                 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
 723                      j = (j + 1) % tid_agg_rx->buf_size) {
 724                         if (!tid_agg_rx->reorder_buf[j]) {
 725                                 skipped++;
 726                                 continue;
 727                         }
 728                         if (skipped &&
 729                             !time_after(jiffies, tid_agg_rx->reorder_time[j] +
 730                                         HT_RX_REORDER_BUF_TIMEOUT))
 731                                 goto set_release_timer;
 732
 733                         ht_dbg_ratelimited(sdata,
 734                                            "release an RX reorder frame due to timeout on earlier frames\n");
 735                         ieee80211_release_reorder_frame(sdata, tid_agg_rx, j,
 736                                                         frames);
 737
 738                         /*
 739                          * Increment the head seq# also for the skipped slots.
 740                          */
 741                         tid_agg_rx->head_seq_num =
 742                                 (tid_agg_rx->head_seq_num +
 743                                  skipped) & IEEE80211_SN_MASK;
 744                         skipped = 0;
 745                 }
 746         } else while (tid_agg_rx->reorder_buf[index]) {
 747                 ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
 748                                                 frames);
 749                 index = ieee80211_sn_sub(tid_agg_rx->head_seq_num,
 750                                          tid_agg_rx->ssn) %
 751                                                         tid_agg_rx->buf_size;
 752         }
 753
 754         if (tid_agg_rx->stored_mpdu_num) {
 755                 j = index = ieee80211_sn_sub(tid_agg_rx->head_seq_num,
 756                                              tid_agg_rx->ssn) %
 757                                                         tid_agg_rx->buf_size;
 758
 759                 for (; j != (index - 1) % tid_agg_rx->buf_size;
 760                      j = (j + 1) % tid_agg_rx->buf_size) {
 761                         if (tid_agg_rx->reorder_buf[j])
 762                                 break;
 763                 }
 764
 765  set_release_timer:
 766
 767                 mod_timer(&tid_agg_rx->reorder_timer,
 768                           tid_agg_rx->reorder_time[j] + 1 +
 769                           HT_RX_REORDER_BUF_TIMEOUT);
 770         } else {
 771                 del_timer(&tid_agg_rx->reorder_timer);
 772         }
 773 }
 774
 775 /*
 776  * As this function belongs to the RX path it must be under
 777  * rcu_read_lock protection. It returns false if the frame
 778  * can be processed immediately, true if it was consumed.
 779  */
 780 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_sub_if_data *sdata,
 781                                              struct tid_ampdu_rx *tid_agg_rx,
 782                                              struct sk_buff *skb,
 783                                              struct sk_buff_head *frames)
 784 {
 785         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 786         u16 sc = le16_to_cpu(hdr->seq_ctrl);
 787         u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
 788         u16 head_seq_num, buf_size;
 789         int index;
 790         bool ret = true;
 791
 792         spin_lock(&tid_agg_rx->reorder_lock);
 793
 794         buf_size = tid_agg_rx->buf_size;
 795         head_seq_num = tid_agg_rx->head_seq_num;
 796
 797         /* frame with out of date sequence number */
 798         if (ieee80211_sn_less(mpdu_seq_num, head_seq_num)) {
 799                 dev_kfree_skb(skb);
 800                 goto out;
 801         }
 802
 803         /*
 804          * If frame the sequence number exceeds our buffering window
 805          * size release some previous frames to make room for this one.
 806          */
 807         if (!ieee80211_sn_less(mpdu_seq_num, head_seq_num + buf_size)) {
 808                 head_seq_num = ieee80211_sn_inc(
 809                                 ieee80211_sn_sub(mpdu_seq_num, buf_size));
 810                 /* release stored frames up to new head to stack */
 811                 ieee80211_release_reorder_frames(sdata, tid_agg_rx,
 812                                                  head_seq_num, frames);
 813         }
 814
 815         /* Now the new frame is always in the range of the reordering buffer */
 816
 817         index = ieee80211_sn_sub(mpdu_seq_num,
 818                                  tid_agg_rx->ssn) % tid_agg_rx->buf_size;
 819
 820         /* check if we already stored this frame */
 821         if (tid_agg_rx->reorder_buf[index]) {
 822                 dev_kfree_skb(skb);
 823                 goto out;
 824         }
 825
 826         /*
 827          * If the current MPDU is in the right order and nothing else
 828          * is stored we can process it directly, no need to buffer it.
 829          * If it is first but there's something stored, we may be able
 830          * to release frames after this one.
 831          */
 832         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
 833             tid_agg_rx->stored_mpdu_num == 0) {
 834                 tid_agg_rx->head_seq_num =
 835                         ieee80211_sn_inc(tid_agg_rx->head_seq_num);
 836                 ret = false;
 837                 goto out;
 838         }
 839
 840         /* put the frame in the reordering buffer */
 841         tid_agg_rx->reorder_buf[index] = skb;
 842         tid_agg_rx->reorder_time[index] = jiffies;
 843         tid_agg_rx->stored_mpdu_num++;
 844         ieee80211_sta_reorder_release(sdata, tid_agg_rx, frames);
 845
 846  out:
 847         spin_unlock(&tid_agg_rx->reorder_lock);
 848         return ret;
 849 }
 850
 851 /*
 852  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
 853  * true if the MPDU was buffered, false if it should be processed.
 854  */
 855 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
 856                                        struct sk_buff_head *frames)
 857 {
 858         struct sk_buff *skb = rx->skb;
 859         struct ieee80211_local *local = rx->local;
 860         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 861         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 862         struct sta_info *sta = rx->sta;
 863         struct tid_ampdu_rx *tid_agg_rx;
 864         u16 sc;
 865         u8 tid, ack_policy;
 866
 867         if (!ieee80211_is_data_qos(hdr->frame_control) ||
 868             is_multicast_ether_addr(hdr->addr1))
 869                 goto dont_reorder;
 870
 871         /*
 872          * filter the QoS data rx stream according to
 873          * STA/TID and check if this STA/TID is on aggregation
 874          */
 875
 876         if (!sta)
 877                 goto dont_reorder;
 878
 879         ack_policy = *ieee80211_get_qos_ctl(hdr) &
 880                      IEEE80211_QOS_CTL_ACK_POLICY_MASK;
 881         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
 882
 883         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
 884         if (!tid_agg_rx)
 885                 goto dont_reorder;
 886
 887         /* qos null data frames are excluded */
 888         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
 889                 goto dont_reorder;
 890
 891         /* not part of a BA session */
 892         if (ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
 893             ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_NORMAL)
 894                 goto dont_reorder;
 895
 896         /* not actually part of this BA session */
 897         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
 898                 goto dont_reorder;
 899
 900         /* new, potentially un-ordered, ampdu frame - process it */
 901
 902         /* reset session timer */
 903         if (tid_agg_rx->timeout)
 904                 tid_agg_rx->last_rx = jiffies;
 905
 906         /* if this mpdu is fragmented - terminate rx aggregation session */
 907         sc = le16_to_cpu(hdr->seq_ctrl);
 908         if (sc & IEEE80211_SCTL_FRAG) {
 909                 skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
 910                 skb_queue_tail(&rx->sdata->skb_queue, skb);
 911                 ieee80211_queue_work(&local->hw, &rx->sdata->work);
 912                 return;
 913         }
 914
 915         /*
 916          * No locking needed -- we will only ever process one
 917          * RX packet at a time, and thus own tid_agg_rx. All
 918          * other code manipulating it needs to (and does) make
 919          * sure that we cannot get to it any more before doing
 920          * anything with it.
 921          */
 922         if (ieee80211_sta_manage_reorder_buf(rx->sdata, tid_agg_rx, skb,
 923                                              frames))
 924                 return;
 925
 926  dont_reorder:
 927         __skb_queue_tail(frames, skb);
 928 }
 929
 930 static ieee80211_rx_result debug_noinline
 931 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
 932 {
 933         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 934         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 935
 936         /*
 937          * Drop duplicate 802.11 retransmissions
 938          * (IEEE 802.11-2012: 9.3.2.10 "Duplicate detection and recovery")
 939          */
 940         if (rx->skb->len >= 24 && rx->sta &&
 941             !ieee80211_is_ctl(hdr->frame_control) &&
 942             !ieee80211_is_qos_nullfunc(hdr->frame_control) &&
 943             !is_multicast_ether_addr(hdr->addr1)) {
 944                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
 945                              rx->sta->last_seq_ctrl[rx->seqno_idx] ==
 946                              hdr->seq_ctrl)) {
 947                         if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
 948                                 rx->local->dot11FrameDuplicateCount++;
 949                                 rx->sta->num_duplicates++;
 950                         }
 951                         return RX_DROP_UNUSABLE;
 952                 } else
 953                         rx->sta->last_seq_ctrl[rx->seqno_idx] = hdr->seq_ctrl;
 954         }
 955
 956         if (unlikely(rx->skb->len < 16)) {
 957                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 958                 return RX_DROP_MONITOR;
 959         }
 960
 961         /* Drop disallowed frame classes based on STA auth/assoc state;
 962          * IEEE 802.11, Chap 5.5.
 963          *
 964          * mac80211 filters only based on association state, i.e. it drops
 965          * Class 3 frames from not associated stations. hostapd sends
 966          * deauth/disassoc frames when needed. In addition, hostapd is
 967          * responsible for filtering on both auth and assoc states.
 968          */
 969
 970         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
 971                 return ieee80211_rx_mesh_check(rx);
 972
 973         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
 974                       ieee80211_is_pspoll(hdr->frame_control)) &&
 975                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
 976                      rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
 977                      (!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_ASSOC)))) {
 978                 /*
 979                  * accept port control frames from the AP even when it's not
 980                  * yet marked ASSOC to prevent a race where we don't set the
 981                  * assoc bit quickly enough before it sends the first frame
 982                  */
 983                 if (rx->sta && rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
 984                     ieee80211_is_data_present(hdr->frame_control)) {
 985                         unsigned int hdrlen;
 986                         __be16 ethertype;
 987
 988                         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 989
 990                         if (rx->skb->len < hdrlen + 8)
 991                                 return RX_DROP_MONITOR;
 992
 993                         skb_copy_bits(rx->skb, hdrlen + 6, &ethertype, 2);
 994                         if (ethertype == rx->sdata->control_port_protocol)
 995                                 return RX_CONTINUE;
 996                 }
 997
 998                 if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
 999                     cfg80211_rx_spurious_frame(rx->sdata->dev,
1000                                                hdr->addr2,
1001                                                GFP_ATOMIC))
1002                         return RX_DROP_UNUSABLE;
1003
1004                 return RX_DROP_MONITOR;
1005         }
1006
1007         return RX_CONTINUE;
1008 }
1009
1010
1011 static ieee80211_rx_result debug_noinline
1012 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
1013 {
1014         struct sk_buff *skb = rx->skb;
1015         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1016         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1017         int keyidx;
1018         int hdrlen;
1019         ieee80211_rx_result result = RX_DROP_UNUSABLE;
1020         struct ieee80211_key *sta_ptk = NULL;
1021         int mmie_keyidx = -1;
1022         __le16 fc;
1023
1024         /*
1025          * Key selection 101
1026          *
1027          * There are four types of keys:
1028          *  - GTK (group keys)
1029          *  - IGTK (group keys for management frames)
1030          *  - PTK (pairwise keys)
1031          *  - STK (station-to-station pairwise keys)
1032          *
1033          * When selecting a key, we have to distinguish between multicast
1034          * (including broadcast) and unicast frames, the latter can only
1035          * use PTKs and STKs while the former always use GTKs and IGTKs.
1036          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
1037          * unicast frames can also use key indices like GTKs. Hence, if we
1038          * don't have a PTK/STK we check the key index for a WEP key.
1039          *
1040          * Note that in a regular BSS, multicast frames are sent by the
1041          * AP only, associated stations unicast the frame to the AP first
1042          * which then multicasts it on their behalf.
1043          *
1044          * There is also a slight problem in IBSS mode: GTKs are negotiated
1045          * with each station, that is something we don't currently handle.
1046          * The spec seems to expect that one negotiates the same key with
1047          * every station but there's no such requirement; VLANs could be
1048          * possible.
1049          */
1050
1051         /*
1052          * No point in finding a key and decrypting if the frame is neither
1053          * addressed to us nor a multicast frame.
1054          */
1055         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1056                 return RX_CONTINUE;
1057
1058         /* start without a key */
1059         rx->key = NULL;
1060
1061         if (rx->sta)
1062                 sta_ptk = rcu_dereference(rx->sta->ptk);
1063
1064         fc = hdr->frame_control;
1065
1066         if (!ieee80211_has_protected(fc))
1067                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
1068
1069         if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
1070                 rx->key = sta_ptk;
1071                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1072                     (status->flag & RX_FLAG_IV_STRIPPED))
1073                         return RX_CONTINUE;
1074                 /* Skip decryption if the frame is not protected. */
1075                 if (!ieee80211_has_protected(fc))
1076                         return RX_CONTINUE;
1077         } else if (mmie_keyidx >= 0) {
1078                 /* Broadcast/multicast robust management frame / BIP */
1079                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1080                     (status->flag & RX_FLAG_IV_STRIPPED))
1081                         return RX_CONTINUE;
1082
1083                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
1084                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
1085                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
1086                 if (rx->sta)
1087                         rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
1088                 if (!rx->key)
1089                         rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
1090         } else if (!ieee80211_has_protected(fc)) {
1091                 /*
1092                  * The frame was not protected, so skip decryption. However, we
1093                  * need to set rx->key if there is a key that could have been
1094                  * used so that the frame may be dropped if encryption would
1095                  * have been expected.
1096                  */
1097                 struct ieee80211_key *key = NULL;
1098                 struct ieee80211_sub_if_data *sdata = rx->sdata;
1099                 int i;
1100
1101                 if (ieee80211_is_mgmt(fc) &&
1102                     is_multicast_ether_addr(hdr->addr1) &&
1103                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
1104                         rx->key = key;
1105                 else {
1106                         if (rx->sta) {
1107                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1108                                         key = rcu_dereference(rx->sta->gtk[i]);
1109                                         if (key)
1110                                                 break;
1111                                 }
1112                         }
1113                         if (!key) {
1114                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1115                                         key = rcu_dereference(sdata->keys[i]);
1116                                         if (key)
1117                                                 break;
1118                                 }
1119                         }
1120                         if (key)
1121                                 rx->key = key;
1122                 }
1123                 return RX_CONTINUE;
1124         } else {
1125                 u8 keyid;
1126                 /*
1127                  * The device doesn't give us the IV so we won't be
1128                  * able to look up the key. That's ok though, we
1129                  * don't need to decrypt the frame, we just won't
1130                  * be able to keep statistics accurate.
1131                  * Except for key threshold notifications, should
1132                  * we somehow allow the driver to tell us which key
1133                  * the hardware used if this flag is set?
1134                  */
1135                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1136                     (status->flag & RX_FLAG_IV_STRIPPED))
1137                         return RX_CONTINUE;
1138
1139                 hdrlen = ieee80211_hdrlen(fc);
1140
1141                 if (rx->skb->len < 8 + hdrlen)
1142                         return RX_DROP_UNUSABLE; /* TODO: count this? */
1143
1144                 /*
1145                  * no need to call ieee80211_wep_get_keyidx,
1146                  * it verifies a bunch of things we've done already
1147                  */
1148                 skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
1149                 keyidx = keyid >> 6;
1150
1151                 /* check per-station GTK first, if multicast packet */
1152                 if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
1153                         rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
1154
1155                 /* if not found, try default key */
1156                 if (!rx->key) {
1157                         rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
1158
1159                         /*
1160                          * RSNA-protected unicast frames should always be
1161                          * sent with pairwise or station-to-station keys,
1162                          * but for WEP we allow using a key index as well.
1163                          */
1164                         if (rx->key &&
1165                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1166                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1167                             !is_multicast_ether_addr(hdr->addr1))
1168                                 rx->key = NULL;
1169                 }
1170         }
1171
1172         if (rx->key) {
1173                 if (unlikely(rx->key->flags & KEY_FLAG_TAINTED))
1174                         return RX_DROP_MONITOR;
1175
1176                 rx->key->tx_rx_count++;
1177                 /* TODO: add threshold stuff again */
1178         } else {
1179                 return RX_DROP_MONITOR;
1180         }
1181
1182         switch (rx->key->conf.cipher) {
1183         case WLAN_CIPHER_SUITE_WEP40:
1184         case WLAN_CIPHER_SUITE_WEP104:
1185                 result = ieee80211_crypto_wep_decrypt(rx);
1186                 break;
1187         case WLAN_CIPHER_SUITE_TKIP:
1188                 result = ieee80211_crypto_tkip_decrypt(rx);
1189                 break;
1190         case WLAN_CIPHER_SUITE_CCMP:
1191                 result = ieee80211_crypto_ccmp_decrypt(rx);
1192                 break;
1193         case WLAN_CIPHER_SUITE_AES_CMAC:
1194                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
1195                 break;
1196         default:
1197                 /*
1198                  * We can reach here only with HW-only algorithms
1199                  * but why didn't it decrypt the frame?!
1200                  */
1201                 return RX_DROP_UNUSABLE;
1202         }
1203
1204         /* the hdr variable is invalid after the decrypt handlers */
1205
1206         /* either the frame has been decrypted or will be dropped */
1207         status->flag |= RX_FLAG_DECRYPTED;
1208
1209         return result;
1210 }
1211
1212 static ieee80211_rx_result debug_noinline
1213 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1214 {
1215         struct ieee80211_local *local;
1216         struct ieee80211_hdr *hdr;
1217         struct sk_buff *skb;
1218
1219         local = rx->local;
1220         skb = rx->skb;
1221         hdr = (struct ieee80211_hdr *) skb->data;
1222
1223         if (!local->pspolling)
1224                 return RX_CONTINUE;
1225
1226         if (!ieee80211_has_fromds(hdr->frame_control))
1227                 /* this is not from AP */
1228                 return RX_CONTINUE;
1229
1230         if (!ieee80211_is_data(hdr->frame_control))
1231                 return RX_CONTINUE;
1232
1233         if (!ieee80211_has_moredata(hdr->frame_control)) {
1234                 /* AP has no more frames buffered for us */
1235                 local->pspolling = false;
1236                 return RX_CONTINUE;
1237         }
1238
1239         /* more data bit is set, let's request a new frame from the AP */
1240         ieee80211_send_pspoll(local, rx->sdata);
1241
1242         return RX_CONTINUE;
1243 }
1244
1245 static void sta_ps_start(struct sta_info *sta)
1246 {
1247         struct ieee80211_sub_if_data *sdata = sta->sdata;
1248         struct ieee80211_local *local = sdata->local;
1249         struct ps_data *ps;
1250
1251         if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
1252             sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1253                 ps = &sdata->bss->ps;
1254         else
1255                 return;
1256
1257         atomic_inc(&ps->num_sta_ps);
1258         set_sta_flag(sta, WLAN_STA_PS_STA);
1259         if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
1260                 drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1261         ps_dbg(sdata, "STA %pM aid %d enters power save mode\n",
1262                sta->sta.addr, sta->sta.aid);
1263 }
1264
1265 static void sta_ps_end(struct sta_info *sta)
1266 {
1267         ps_dbg(sta->sdata, "STA %pM aid %d exits power save mode\n",
1268                sta->sta.addr, sta->sta.aid);
1269
1270         if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) {
1271                 ps_dbg(sta->sdata, "STA %pM aid %d driver-ps-blocked\n",
1272                        sta->sta.addr, sta->sta.aid);
1273                 return;
1274         }
1275
1276         ieee80211_sta_ps_deliver_wakeup(sta);
1277 }
1278
1279 int ieee80211_sta_ps_transition(struct ieee80211_sta *sta, bool start)
1280 {
1281         struct sta_info *sta_inf = container_of(sta, struct sta_info, sta);
1282         bool in_ps;
1283
1284         WARN_ON(!(sta_inf->local->hw.flags & IEEE80211_HW_AP_LINK_PS));
1285
1286         /* Don't let the same PS state be set twice */
1287         in_ps = test_sta_flag(sta_inf, WLAN_STA_PS_STA);
1288         if ((start && in_ps) || (!start && !in_ps))
1289                 return -EINVAL;
1290
1291         if (start)
1292                 sta_ps_start(sta_inf);
1293         else
1294                 sta_ps_end(sta_inf);
1295
1296         return 0;
1297 }
1298 EXPORT_SYMBOL(ieee80211_sta_ps_transition);
1299
1300 static ieee80211_rx_result debug_noinline
1301 ieee80211_rx_h_uapsd_and_pspoll(struct ieee80211_rx_data *rx)
1302 {
1303         struct ieee80211_sub_if_data *sdata = rx->sdata;
1304         struct ieee80211_hdr *hdr = (void *)rx->skb->data;
1305         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1306         int tid, ac;
1307
1308         if (!rx->sta || !(status->rx_flags & IEEE80211_RX_RA_MATCH))
1309                 return RX_CONTINUE;
1310
1311         if (sdata->vif.type != NL80211_IFTYPE_AP &&
1312             sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
1313                 return RX_CONTINUE;
1314
1315         /*
1316          * The device handles station powersave, so don't do anything about
1317          * uAPSD and PS-Poll frames (the latter shouldn't even come up from
1318          * it to mac80211 since they're handled.)
1319          */
1320         if (sdata->local->hw.flags & IEEE80211_HW_AP_LINK_PS)
1321                 return RX_CONTINUE;
1322
1323         /*
1324          * Don't do anything if the station isn't already asleep. In
1325          * the uAPSD case, the station will probably be marked asleep,
1326          * in the PS-Poll case the station must be confused ...
1327          */
1328         if (!test_sta_flag(rx->sta, WLAN_STA_PS_STA))
1329                 return RX_CONTINUE;
1330
1331         if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) {
1332                 if (!test_sta_flag(rx->sta, WLAN_STA_SP)) {
1333                         if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1334                                 ieee80211_sta_ps_deliver_poll_response(rx->sta);
1335                         else
1336                                 set_sta_flag(rx->sta, WLAN_STA_PSPOLL);
1337                 }
1338
1339                 /* Free PS Poll skb here instead of returning RX_DROP that would
1340                  * count as an dropped frame. */
1341                 dev_kfree_skb(rx->skb);
1342
1343                 return RX_QUEUED;
1344         } else if (!ieee80211_has_morefrags(hdr->frame_control) &&
1345                    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1346                    ieee80211_has_pm(hdr->frame_control) &&
1347                    (ieee80211_is_data_qos(hdr->frame_control) ||
1348                     ieee80211_is_qos_nullfunc(hdr->frame_control))) {
1349                 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
1350                 ac = ieee802_1d_to_ac[tid & 7];
1351
1352                 /*
1353                  * If this AC is not trigger-enabled do nothing.
1354                  *
1355                  * NB: This could/should check a separate bitmap of trigger-
1356                  * enabled queues, but for now we only implement uAPSD w/o
1357                  * TSPEC changes to the ACs, so they're always the same.
1358                  */
1359                 if (!(rx->sta->sta.uapsd_queues & BIT(ac)))
1360                         return RX_CONTINUE;
1361
1362                 /* if we are in a service period, do nothing */
1363                 if (test_sta_flag(rx->sta, WLAN_STA_SP))
1364                         return RX_CONTINUE;
1365
1366                 if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1367                         ieee80211_sta_ps_deliver_uapsd(rx->sta);
1368                 else
1369                         set_sta_flag(rx->sta, WLAN_STA_UAPSD);
1370         }
1371
1372         return RX_CONTINUE;
1373 }
1374
1375 static ieee80211_rx_result debug_noinline
1376 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1377 {
1378         struct sta_info *sta = rx->sta;
1379         struct sk_buff *skb = rx->skb;
1380         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1381         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1382
1383         if (!sta)
1384                 return RX_CONTINUE;
1385
1386         /*
1387          * Update last_rx only for IBSS packets which are for the current
1388          * BSSID and for station already AUTHORIZED to avoid keeping the
1389          * current IBSS network alive in cases where other STAs start
1390          * using different BSSID. This will also give the station another
1391          * chance to restart the authentication/authorization in case
1392          * something went wrong the first time.
1393          */
1394         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1395                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1396                                                 NL80211_IFTYPE_ADHOC);
1397                 if (ether_addr_equal(bssid, rx->sdata->u.ibss.bssid) &&
1398                     test_sta_flag(sta, WLAN_STA_AUTHORIZED)) {
1399                         sta->last_rx = jiffies;
1400                         if (ieee80211_is_data(hdr->frame_control)) {
1401                                 sta->last_rx_rate_idx = status->rate_idx;
1402                                 sta->last_rx_rate_flag = status->flag;
1403                                 sta->last_rx_rate_vht_nss = status->vht_nss;
1404                         }
1405                 }
1406         } else if (!is_multicast_ether_addr(hdr->addr1)) {
1407                 /*
1408                  * Mesh beacons will update last_rx when if they are found to
1409                  * match the current local configuration when processed.
1410                  */
1411                 sta->last_rx = jiffies;
1412                 if (ieee80211_is_data(hdr->frame_control)) {
1413                         sta->last_rx_rate_idx = status->rate_idx;
1414                         sta->last_rx_rate_flag = status->flag;
1415                         sta->last_rx_rate_vht_nss = status->vht_nss;
1416                 }
1417         }
1418
1419         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1420                 return RX_CONTINUE;
1421
1422         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1423                 ieee80211_sta_rx_notify(rx->sdata, hdr);
1424
1425         sta->rx_fragments++;
1426         sta->rx_bytes += rx->skb->len;
1427         if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
1428                 sta->last_signal = status->signal;
1429                 ewma_add(&sta->avg_signal, -status->signal);
1430         }
1431
1432         /*
1433          * Change STA power saving mode only at the end of a frame
1434          * exchange sequence.
1435          */
1436         if (!(sta->local->hw.flags & IEEE80211_HW_AP_LINK_PS) &&
1437             !ieee80211_has_morefrags(hdr->frame_control) &&
1438             !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1439             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1440              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1441                 if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
1442                         /*
1443                          * Ignore doze->wake transitions that are
1444                          * indicated by non-data frames, the standard
1445                          * is unclear here, but for example going to
1446                          * PS mode and then scanning would cause a
1447                          * doze->wake transition for the probe request,
1448                          * and that is clearly undesirable.
1449                          */
1450                         if (ieee80211_is_data(hdr->frame_control) &&
1451                             !ieee80211_has_pm(hdr->frame_control))
1452                                 sta_ps_end(sta);
1453                 } else {
1454                         if (ieee80211_has_pm(hdr->frame_control))
1455                                 sta_ps_start(sta);
1456                 }
1457         }
1458
1459         /* mesh power save support */
1460         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
1461                 ieee80211_mps_rx_h_sta_process(sta, hdr);
1462
1463         /*
1464          * Drop (qos-)data::nullfunc frames silently, since they
1465          * are used only to control station power saving mode.
1466          */
1467         if (ieee80211_is_nullfunc(hdr->frame_control) ||
1468             ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1469                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1470
1471                 /*
1472                  * If we receive a 4-addr nullfunc frame from a STA
1473                  * that was not moved to a 4-addr STA vlan yet send
1474                  * the event to userspace and for older hostapd drop
1475                  * the frame to the monitor interface.
1476                  */
1477                 if (ieee80211_has_a4(hdr->frame_control) &&
1478                     (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1479                      (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1480                       !rx->sdata->u.vlan.sta))) {
1481                         if (!test_and_set_sta_flag(sta, WLAN_STA_4ADDR_EVENT))
1482                                 cfg80211_rx_unexpected_4addr_frame(
1483                                         rx->sdata->dev, sta->sta.addr,
1484                                         GFP_ATOMIC);
1485                         return RX_DROP_MONITOR;
1486                 }
1487                 /*
1488                  * Update counter and free packet here to avoid
1489                  * counting this as a dropped packed.
1490                  */
1491                 sta->rx_packets++;
1492                 dev_kfree_skb(rx->skb);
1493                 return RX_QUEUED;
1494         }
1495
1496         return RX_CONTINUE;
1497 } /* ieee80211_rx_h_sta_process */
1498
1499 static inline struct ieee80211_fragment_entry *
1500 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1501                          unsigned int frag, unsigned int seq, int rx_queue,
1502                          struct sk_buff **skb)
1503 {
1504         struct ieee80211_fragment_entry *entry;
1505
1506         entry = &sdata->fragments[sdata->fragment_next++];
1507         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1508                 sdata->fragment_next = 0;
1509
1510         if (!skb_queue_empty(&entry->skb_list))
1511                 __skb_queue_purge(&entry->skb_list);
1512
1513         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1514         *skb = NULL;
1515         entry->first_frag_time = jiffies;
1516         entry->seq = seq;
1517         entry->rx_queue = rx_queue;
1518         entry->last_frag = frag;
1519         entry->ccmp = 0;
1520         entry->extra_len = 0;
1521
1522         return entry;
1523 }
1524
1525 static inline struct ieee80211_fragment_entry *
1526 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1527                           unsigned int frag, unsigned int seq,
1528                           int rx_queue, struct ieee80211_hdr *hdr)
1529 {
1530         struct ieee80211_fragment_entry *entry;
1531         int i, idx;
1532
1533         idx = sdata->fragment_next;
1534         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1535                 struct ieee80211_hdr *f_hdr;
1536
1537                 idx--;
1538                 if (idx < 0)
1539                         idx = IEEE80211_FRAGMENT_MAX - 1;
1540
1541                 entry = &sdata->fragments[idx];
1542                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1543                     entry->rx_queue != rx_queue ||
1544                     entry->last_frag + 1 != frag)
1545                         continue;
1546
1547                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1548
1549                 /*
1550                  * Check ftype and addresses are equal, else check next fragment
1551                  */
1552                 if (((hdr->frame_control ^ f_hdr->frame_control) &
1553                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1554                     !ether_addr_equal(hdr->addr1, f_hdr->addr1) ||
1555                     !ether_addr_equal(hdr->addr2, f_hdr->addr2))
1556                         continue;
1557
1558                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1559                         __skb_queue_purge(&entry->skb_list);
1560                         continue;
1561                 }
1562                 return entry;
1563         }
1564
1565         return NULL;
1566 }
1567
1568 static ieee80211_rx_result debug_noinline
1569 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1570 {
1571         struct ieee80211_hdr *hdr;
1572         u16 sc;
1573         __le16 fc;
1574         unsigned int frag, seq;
1575         struct ieee80211_fragment_entry *entry;
1576         struct sk_buff *skb;
1577         struct ieee80211_rx_status *status;
1578
1579         hdr = (struct ieee80211_hdr *)rx->skb->data;
1580         fc = hdr->frame_control;
1581
1582         if (ieee80211_is_ctl(fc))
1583                 return RX_CONTINUE;
1584
1585         sc = le16_to_cpu(hdr->seq_ctrl);
1586         frag = sc & IEEE80211_SCTL_FRAG;
1587
1588         if (is_multicast_ether_addr(hdr->addr1)) {
1589                 rx->local->dot11MulticastReceivedFrameCount++;
1590                 goto out_no_led;
1591         }
1592
1593         if (likely(!ieee80211_has_morefrags(fc) && frag == 0))
1594                 goto out;
1595
1596         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1597
1598         if (skb_linearize(rx->skb))
1599                 return RX_DROP_UNUSABLE;
1600
1601         /*
1602          *  skb_linearize() might change the skb->data and
1603          *  previously cached variables (in this case, hdr) need to
1604          *  be refreshed with the new data.
1605          */
1606         hdr = (struct ieee80211_hdr *)rx->skb->data;
1607         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1608
1609         if (frag == 0) {
1610                 /* This is the first fragment of a new frame. */
1611                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1612                                                  rx->seqno_idx, &(rx->skb));
1613                 if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP &&
1614                     ieee80211_has_protected(fc)) {
1615                         int queue = rx->security_idx;
1616                         /* Store CCMP PN so that we can verify that the next
1617                          * fragment has a sequential PN value. */
1618                         entry->ccmp = 1;
1619                         memcpy(entry->last_pn,
1620                                rx->key->u.ccmp.rx_pn[queue],
1621                                CCMP_PN_LEN);
1622                 }
1623                 return RX_QUEUED;
1624         }
1625
1626         /* This is a fragment for a frame that should already be pending in
1627          * fragment cache. Add this fragment to the end of the pending entry.
1628          */
1629         entry = ieee80211_reassemble_find(rx->sdata, frag, seq,
1630                                           rx->seqno_idx, hdr);
1631         if (!entry) {
1632                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1633                 return RX_DROP_MONITOR;
1634         }
1635
1636         /* Verify that MPDUs within one MSDU have sequential PN values.
1637          * (IEEE 802.11i, 8.3.3.4.5) */
1638         if (entry->ccmp) {
1639                 int i;
1640                 u8 pn[CCMP_PN_LEN], *rpn;
1641                 int queue;
1642                 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP)
1643                         return RX_DROP_UNUSABLE;
1644                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1645                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1646                         pn[i]++;
1647                         if (pn[i])
1648                                 break;
1649                 }
1650                 queue = rx->security_idx;
1651                 rpn = rx->key->u.ccmp.rx_pn[queue];
1652                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1653                         return RX_DROP_UNUSABLE;
1654                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1655         }
1656
1657         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1658         __skb_queue_tail(&entry->skb_list, rx->skb);
1659         entry->last_frag = frag;
1660         entry->extra_len += rx->skb->len;
1661         if (ieee80211_has_morefrags(fc)) {
1662                 rx->skb = NULL;
1663                 return RX_QUEUED;
1664         }
1665
1666         rx->skb = __skb_dequeue(&entry->skb_list);
1667         if (skb_tailroom(rx->skb) < entry->extra_len) {
1668                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1669                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1670                                               GFP_ATOMIC))) {
1671                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1672                         __skb_queue_purge(&entry->skb_list);
1673                         return RX_DROP_UNUSABLE;
1674                 }
1675         }
1676         while ((skb = __skb_dequeue(&entry->skb_list))) {
1677                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1678                 dev_kfree_skb(skb);
1679         }
1680
1681         /* Complete frame has been reassembled - process it now */
1682         status = IEEE80211_SKB_RXCB(rx->skb);
1683         status->rx_flags |= IEEE80211_RX_FRAGMENTED;
1684
1685  out:
1686         ieee80211_led_rx(rx->local);
1687  out_no_led:
1688         if (rx->sta)
1689                 rx->sta->rx_packets++;
1690         return RX_CONTINUE;
1691 }
1692
1693 static int ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1694 {
1695         if (unlikely(!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_AUTHORIZED)))
1696                 return -EACCES;
1697
1698         return 0;
1699 }
1700
1701 static int ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1702 {
1703         struct sk_buff *skb = rx->skb;
1704         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1705
1706         /*
1707          * Pass through unencrypted frames if the hardware has
1708          * decrypted them already.
1709          */
1710         if (status->flag & RX_FLAG_DECRYPTED)
1711                 return 0;
1712
1713         /* Drop unencrypted frames if key is set. */
1714         if (unlikely(!ieee80211_has_protected(fc) &&
1715                      !ieee80211_is_nullfunc(fc) &&
1716                      ieee80211_is_data(fc) &&
1717                      (rx->key || rx->sdata->drop_unencrypted)))
1718                 return -EACCES;
1719
1720         return 0;
1721 }
1722
1723 static int ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1724 {
1725         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1726         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1727         __le16 fc = hdr->frame_control;
1728
1729         /*
1730          * Pass through unencrypted frames if the hardware has
1731          * decrypted them already.
1732          */
1733         if (status->flag & RX_FLAG_DECRYPTED)
1734                 return 0;
1735
1736         if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) {
1737                 if (unlikely(!ieee80211_has_protected(fc) &&
1738                              ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1739                              rx->key)) {
1740                         if (ieee80211_is_deauth(fc))
1741                                 cfg80211_send_unprot_deauth(rx->sdata->dev,
1742                                                             rx->skb->data,
1743                                                             rx->skb->len);
1744                         else if (ieee80211_is_disassoc(fc))
1745                                 cfg80211_send_unprot_disassoc(rx->sdata->dev,
1746                                                               rx->skb->data,
1747                                                               rx->skb->len);
1748                         return -EACCES;
1749                 }
1750                 /* BIP does not use Protected field, so need to check MMIE */
1751                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1752                              ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
1753                         if (ieee80211_is_deauth(fc))
1754                                 cfg80211_send_unprot_deauth(rx->sdata->dev,
1755                                                             rx->skb->data,
1756                                                             rx->skb->len);
1757                         else if (ieee80211_is_disassoc(fc))
1758                                 cfg80211_send_unprot_disassoc(rx->sdata->dev,
1759                                                               rx->skb->data,
1760                                                               rx->skb->len);
1761                         return -EACCES;
1762                 }
1763                 /*
1764                  * When using MFP, Action frames are not allowed prior to
1765                  * having configured keys.
1766                  */
1767                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1768                              ieee80211_is_robust_mgmt_frame(
1769                                      (struct ieee80211_hdr *) rx->skb->data)))
1770                         return -EACCES;
1771         }
1772
1773         return 0;
1774 }
1775
1776 static int
1777 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx, bool *port_control)
1778 {
1779         struct ieee80211_sub_if_data *sdata = rx->sdata;
1780         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1781         bool check_port_control = false;
1782         struct ethhdr *ehdr;
1783         int ret;
1784
1785         *port_control = false;
1786         if (ieee80211_has_a4(hdr->frame_control) &&
1787             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1788                 return -1;
1789
1790         if (sdata->vif.type == NL80211_IFTYPE_STATION &&
1791             !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) {
1792
1793                 if (!sdata->u.mgd.use_4addr)
1794                         return -1;
1795                 else
1796                         check_port_control = true;
1797         }
1798
1799         if (is_multicast_ether_addr(hdr->addr1) &&
1800             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta)
1801                 return -1;
1802
1803         ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1804         if (ret < 0)
1805                 return ret;
1806
1807         ehdr = (struct ethhdr *) rx->skb->data;
1808         if (ehdr->h_proto == rx->sdata->control_port_protocol)
1809                 *port_control = true;
1810         else if (check_port_control)
1811                 return -1;
1812
1813         return 0;
1814 }
1815
1816 /*
1817  * requires that rx->skb is a frame with ethernet header
1818  */
1819 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1820 {
1821         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1822                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1823         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1824
1825         /*
1826          * Allow EAPOL frames to us/the PAE group address regardless
1827          * of whether the frame was encrypted or not.
1828          */
1829         if (ehdr->h_proto == rx->sdata->control_port_protocol &&
1830             (ether_addr_equal(ehdr->h_dest, rx->sdata->vif.addr) ||
1831              ether_addr_equal(ehdr->h_dest, pae_group_addr)))
1832                 return true;
1833
1834         if (ieee80211_802_1x_port_control(rx) ||
1835             ieee80211_drop_unencrypted(rx, fc))
1836                 return false;
1837
1838         return true;
1839 }
1840
1841 /*
1842  * requires that rx->skb is a frame with ethernet header
1843  */
1844 static void
1845 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1846 {
1847         struct ieee80211_sub_if_data *sdata = rx->sdata;
1848         struct net_device *dev = sdata->dev;
1849         struct sk_buff *skb, *xmit_skb;
1850         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1851         struct sta_info *dsta;
1852         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1853
1854         skb = rx->skb;
1855         xmit_skb = NULL;
1856
1857         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1858              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1859             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1860             (status->rx_flags & IEEE80211_RX_RA_MATCH) &&
1861             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1862                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1863                         /*
1864                          * send multicast frames both to higher layers in
1865                          * local net stack and back to the wireless medium
1866                          */
1867                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1868                         if (!xmit_skb)
1869                                 net_info_ratelimited("%s: failed to clone multicast frame\n",
1870                                                     dev->name);
1871                 } else {
1872                         dsta = sta_info_get(sdata, skb->data);
1873                         if (dsta) {
1874                                 /*
1875                                  * The destination station is associated to
1876                                  * this AP (in this VLAN), so send the frame
1877                                  * directly to it and do not pass it to local
1878                                  * net stack.
1879                                  */
1880                                 xmit_skb = skb;
1881                                 skb = NULL;
1882                         }
1883                 }
1884         }
1885
1886         if (skb) {
1887                 int align __maybe_unused;
1888
1889 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1890                 /*
1891                  * 'align' will only take the values 0 or 2 here
1892                  * since all frames are required to be aligned
1893                  * to 2-byte boundaries when being passed to
1894                  * mac80211; the code here works just as well if
1895                  * that isn't true, but mac80211 assumes it can
1896                  * access fields as 2-byte aligned (e.g. for
1897                  * compare_ether_addr)
1898                  */
1899                 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1900                 if (align) {
1901                         if (WARN_ON(skb_headroom(skb) < 3)) {
1902                                 dev_kfree_skb(skb);
1903                                 skb = NULL;
1904                         } else {
1905                                 u8 *data = skb->data;
1906                                 size_t len = skb_headlen(skb);
1907                                 skb->data -= align;
1908                                 memmove(skb->data, data, len);
1909                                 skb_set_tail_pointer(skb, len);
1910                         }
1911                 }
1912 #endif
1913
1914                 if (skb) {
1915                         /* deliver to local stack */
1916                         skb->protocol = eth_type_trans(skb, dev);
1917                         memset(skb->cb, 0, sizeof(skb->cb));
1918                         netif_receive_skb(skb);
1919                 }
1920         }
1921
1922         if (xmit_skb) {
1923                 /*
1924                  * Send to wireless media and increase priority by 256 to
1925                  * keep the received priority instead of reclassifying
1926                  * the frame (see cfg80211_classify8021d).
1927                  */
1928                 xmit_skb->priority += 256;
1929                 xmit_skb->protocol = htons(ETH_P_802_3);
1930                 skb_reset_network_header(xmit_skb);
1931                 skb_reset_mac_header(xmit_skb);
1932                 dev_queue_xmit(xmit_skb);
1933         }
1934 }
1935
1936 static ieee80211_rx_result debug_noinline
1937 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1938 {
1939         struct net_device *dev = rx->sdata->dev;
1940         struct sk_buff *skb = rx->skb;
1941         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1942         __le16 fc = hdr->frame_control;
1943         struct sk_buff_head frame_list;
1944         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1945
1946         if (unlikely(!ieee80211_is_data(fc)))
1947                 return RX_CONTINUE;
1948
1949         if (unlikely(!ieee80211_is_data_present(fc)))
1950                 return RX_DROP_MONITOR;
1951
1952         if (!(status->rx_flags & IEEE80211_RX_AMSDU))
1953                 return RX_CONTINUE;
1954
1955         if (ieee80211_has_a4(hdr->frame_control) &&
1956             rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1957             !rx->sdata->u.vlan.sta)
1958                 return RX_DROP_UNUSABLE;
1959
1960         if (is_multicast_ether_addr(hdr->addr1) &&
1961             ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1962               rx->sdata->u.vlan.sta) ||
1963              (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1964               rx->sdata->u.mgd.use_4addr)))
1965                 return RX_DROP_UNUSABLE;
1966
1967         skb->dev = dev;
1968         __skb_queue_head_init(&frame_list);
1969
1970         if (skb_linearize(skb))
1971                 return RX_DROP_UNUSABLE;
1972
1973         ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1974                                  rx->sdata->vif.type,
1975                                  rx->local->hw.extra_tx_headroom, true);
1976
1977         while (!skb_queue_empty(&frame_list)) {
1978                 rx->skb = __skb_dequeue(&frame_list);
1979
1980                 if (!ieee80211_frame_allowed(rx, fc)) {
1981                         dev_kfree_skb(rx->skb);
1982                         continue;
1983                 }
1984                 dev->stats.rx_packets++;
1985                 dev->stats.rx_bytes += rx->skb->len;
1986
1987                 ieee80211_deliver_skb(rx);
1988         }
1989
1990         return RX_QUEUED;
1991 }
1992
1993 #ifdef CONFIG_MAC80211_MESH
1994 static ieee80211_rx_result
1995 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1996 {
1997         struct ieee80211_hdr *fwd_hdr, *hdr;
1998         struct ieee80211_tx_info *info;
1999         struct ieee80211s_hdr *mesh_hdr;
2000         struct sk_buff *skb = rx->skb, *fwd_skb;
2001         struct ieee80211_local *local = rx->local;
2002         struct ieee80211_sub_if_data *sdata = rx->sdata;
2003         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2004         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
2005         __le16 reason = cpu_to_le16(WLAN_REASON_MESH_PATH_NOFORWARD);
2006         u16 q, hdrlen;
2007
2008         hdr = (struct ieee80211_hdr *) skb->data;
2009         hdrlen = ieee80211_hdrlen(hdr->frame_control);
2010
2011         /* make sure fixed part of mesh header is there, also checks skb len */
2012         if (!pskb_may_pull(rx->skb, hdrlen + 6))
2013                 return RX_DROP_MONITOR;
2014
2015         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2016
2017         /* make sure full mesh header is there, also checks skb len */
2018         if (!pskb_may_pull(rx->skb,
2019                            hdrlen + ieee80211_get_mesh_hdrlen(mesh_hdr)))
2020                 return RX_DROP_MONITOR;
2021
2022         /* reload pointers */
2023         hdr = (struct ieee80211_hdr *) skb->data;
2024         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2025
2026         /* frame is in RMC, don't forward */
2027         if (ieee80211_is_data(hdr->frame_control) &&
2028             is_multicast_ether_addr(hdr->addr1) &&
2029             mesh_rmc_check(rx->sdata, hdr->addr3, mesh_hdr))
2030                 return RX_DROP_MONITOR;
2031
2032         if (!ieee80211_is_data(hdr->frame_control) ||
2033             !(status->rx_flags & IEEE80211_RX_RA_MATCH))
2034                 return RX_CONTINUE;
2035
2036         if (!mesh_hdr->ttl)
2037                 return RX_DROP_MONITOR;
2038
2039         if (mesh_hdr->flags & MESH_FLAGS_AE) {
2040                 struct mesh_path *mppath;
2041                 char *proxied_addr;
2042                 char *mpp_addr;
2043
2044                 if (is_multicast_ether_addr(hdr->addr1)) {
2045                         mpp_addr = hdr->addr3;
2046                         proxied_addr = mesh_hdr->eaddr1;
2047                 } else if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6) {
2048                         /* has_a4 already checked in ieee80211_rx_mesh_check */
2049                         mpp_addr = hdr->addr4;
2050                         proxied_addr = mesh_hdr->eaddr2;
2051                 } else {
2052                         return RX_DROP_MONITOR;
2053                 }
2054
2055                 rcu_read_lock();
2056                 mppath = mpp_path_lookup(sdata, proxied_addr);
2057                 if (!mppath) {
2058                         mpp_path_add(sdata, proxied_addr, mpp_addr);
2059                 } else {
2060                         spin_lock_bh(&mppath->state_lock);
2061                         if (!ether_addr_equal(mppath->mpp, mpp_addr))
2062                                 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
2063                         spin_unlock_bh(&mppath->state_lock);
2064                 }
2065                 rcu_read_unlock();
2066         }
2067
2068         /* Frame has reached destination.  Don't forward */
2069         if (!is_multicast_ether_addr(hdr->addr1) &&
2070             ether_addr_equal(sdata->vif.addr, hdr->addr3))
2071                 return RX_CONTINUE;
2072
2073         q = ieee80211_select_queue_80211(sdata, skb, hdr);
2074         if (ieee80211_queue_stopped(&local->hw, q)) {
2075                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion);
2076                 return RX_DROP_MONITOR;
2077         }
2078         skb_set_queue_mapping(skb, q);
2079
2080         if (!--mesh_hdr->ttl) {
2081                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
2082                 goto out;
2083         }
2084
2085         if (!ifmsh->mshcfg.dot11MeshForwarding)
2086                 goto out;
2087
2088         fwd_skb = skb_copy(skb, GFP_ATOMIC);
2089         if (!fwd_skb) {
2090                 net_info_ratelimited("%s: failed to clone mesh frame\n",
2091                                     sdata->name);
2092                 goto out;
2093         }
2094
2095         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
2096         fwd_hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_RETRY);
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_PUBLIC:
2436                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2437                         goto invalid;
2438                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2439                         break;
2440                 if (!rx->sta)
2441                         break;
2442                 if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
2443                         break;
2444                 if (mgmt->u.action.u.ext_chan_switch.action_code !=
2445                                 WLAN_PUB_ACTION_EXT_CHANSW_ANN)
2446                         break;
2447                 if (len < offsetof(struct ieee80211_mgmt,
2448                                    u.action.u.ext_chan_switch.variable))
2449                         goto invalid;
2450                 goto queue;
2451         case WLAN_CATEGORY_VHT:
2452                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2453                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2454                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2455                     sdata->vif.type != NL80211_IFTYPE_AP &&
2456                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2457                         break;
2458
2459                 /* verify action code is present */
2460                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2461                         goto invalid;
2462
2463                 switch (mgmt->u.action.u.vht_opmode_notif.action_code) {
2464                 case WLAN_VHT_ACTION_OPMODE_NOTIF: {
2465                         u8 opmode;
2466
2467                         /* verify opmode is present */
2468                         if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2469                                 goto invalid;
2470
2471                         opmode = mgmt->u.action.u.vht_opmode_notif.operating_mode;
2472
2473                         ieee80211_vht_handle_opmode(rx->sdata, rx->sta,
2474                                                     opmode, status->band,
2475                                                     false);
2476                         goto handled;
2477                 }
2478                 default:
2479                         break;
2480                 }
2481                 break;
2482         case WLAN_CATEGORY_BACK:
2483                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2484                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2485                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2486                     sdata->vif.type != NL80211_IFTYPE_AP &&
2487                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2488                         break;
2489
2490                 /* verify action_code is present */
2491                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2492                         break;
2493
2494                 switch (mgmt->u.action.u.addba_req.action_code) {
2495                 case WLAN_ACTION_ADDBA_REQ:
2496                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2497                                    sizeof(mgmt->u.action.u.addba_req)))
2498                                 goto invalid;
2499                         break;
2500                 case WLAN_ACTION_ADDBA_RESP:
2501                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2502                                    sizeof(mgmt->u.action.u.addba_resp)))
2503                                 goto invalid;
2504                         break;
2505                 case WLAN_ACTION_DELBA:
2506                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2507                                    sizeof(mgmt->u.action.u.delba)))
2508                                 goto invalid;
2509                         break;
2510                 default:
2511                         goto invalid;
2512                 }
2513
2514                 goto queue;
2515         case WLAN_CATEGORY_SPECTRUM_MGMT:
2516                 if (status->band != IEEE80211_BAND_5GHZ)
2517                         break;
2518
2519                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2520                         break;
2521
2522                 /* verify action_code is present */
2523                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2524                         break;
2525
2526                 switch (mgmt->u.action.u.measurement.action_code) {
2527                 case WLAN_ACTION_SPCT_MSR_REQ:
2528                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2529                                    sizeof(mgmt->u.action.u.measurement)))
2530                                 break;
2531                         ieee80211_process_measurement_req(sdata, mgmt, len);
2532                         goto handled;
2533                 case WLAN_ACTION_SPCT_CHL_SWITCH:
2534                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2535                                 break;
2536
2537                         if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
2538                                 break;
2539
2540                         goto queue;
2541                 }
2542                 break;
2543         case WLAN_CATEGORY_SA_QUERY:
2544                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2545                            sizeof(mgmt->u.action.u.sa_query)))
2546                         break;
2547
2548                 switch (mgmt->u.action.u.sa_query.action) {
2549                 case WLAN_ACTION_SA_QUERY_REQUEST:
2550                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2551                                 break;
2552                         ieee80211_process_sa_query_req(sdata, mgmt, len);
2553                         goto handled;
2554                 }
2555                 break;
2556         case WLAN_CATEGORY_SELF_PROTECTED:
2557                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2558                            sizeof(mgmt->u.action.u.self_prot.action_code)))
2559                         break;
2560
2561                 switch (mgmt->u.action.u.self_prot.action_code) {
2562                 case WLAN_SP_MESH_PEERING_OPEN:
2563                 case WLAN_SP_MESH_PEERING_CLOSE:
2564                 case WLAN_SP_MESH_PEERING_CONFIRM:
2565                         if (!ieee80211_vif_is_mesh(&sdata->vif))
2566                                 goto invalid;
2567                         if (sdata->u.mesh.user_mpm)
2568                                 /* userspace handles this frame */
2569                                 break;
2570                         goto queue;
2571                 case WLAN_SP_MGK_INFORM:
2572                 case WLAN_SP_MGK_ACK:
2573                         if (!ieee80211_vif_is_mesh(&sdata->vif))
2574                                 goto invalid;
2575                         break;
2576                 }
2577                 break;
2578         case WLAN_CATEGORY_MESH_ACTION:
2579                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2580                            sizeof(mgmt->u.action.u.mesh_action.action_code)))
2581                         break;
2582
2583                 if (!ieee80211_vif_is_mesh(&sdata->vif))
2584                         break;
2585                 if (mesh_action_is_path_sel(mgmt) &&
2586                     !mesh_path_sel_is_hwmp(sdata))
2587                         break;
2588                 goto queue;
2589         }
2590
2591         return RX_CONTINUE;
2592
2593  invalid:
2594         status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
2595         /* will return in the next handlers */
2596         return RX_CONTINUE;
2597
2598  handled:
2599         if (rx->sta)
2600                 rx->sta->rx_packets++;
2601         dev_kfree_skb(rx->skb);
2602         return RX_QUEUED;
2603
2604  queue:
2605         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2606         skb_queue_tail(&sdata->skb_queue, rx->skb);
2607         ieee80211_queue_work(&local->hw, &sdata->work);
2608         if (rx->sta)
2609                 rx->sta->rx_packets++;
2610         return RX_QUEUED;
2611 }
2612
2613 static ieee80211_rx_result debug_noinline
2614 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
2615 {
2616         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2617         int sig = 0;
2618
2619         /* skip known-bad action frames and return them in the next handler */
2620         if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
2621                 return RX_CONTINUE;
2622
2623         /*
2624          * Getting here means the kernel doesn't know how to handle
2625          * it, but maybe userspace does ... include returned frames
2626          * so userspace can register for those to know whether ones
2627          * it transmitted were processed or returned.
2628          */
2629
2630         if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2631                 sig = status->signal;
2632
2633         if (cfg80211_rx_mgmt(&rx->sdata->wdev, status->freq, sig,
2634                              rx->skb->data, rx->skb->len,
2635                              GFP_ATOMIC)) {
2636                 if (rx->sta)
2637                         rx->sta->rx_packets++;
2638                 dev_kfree_skb(rx->skb);
2639                 return RX_QUEUED;
2640         }
2641
2642         return RX_CONTINUE;
2643 }
2644
2645 static ieee80211_rx_result debug_noinline
2646 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
2647 {
2648         struct ieee80211_local *local = rx->local;
2649         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2650         struct sk_buff *nskb;
2651         struct ieee80211_sub_if_data *sdata = rx->sdata;
2652         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2653
2654         if (!ieee80211_is_action(mgmt->frame_control))
2655                 return RX_CONTINUE;
2656
2657         /*
2658          * For AP mode, hostapd is responsible for handling any action
2659          * frames that we didn't handle, including returning unknown
2660          * ones. For all other modes we will return them to the sender,
2661          * setting the 0x80 bit in the action category, as required by
2662          * 802.11-2012 9.24.4.
2663          * Newer versions of hostapd shall also use the management frame
2664          * registration mechanisms, but older ones still use cooked
2665          * monitor interfaces so push all frames there.
2666          */
2667         if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
2668             (sdata->vif.type == NL80211_IFTYPE_AP ||
2669              sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
2670                 return RX_DROP_MONITOR;
2671
2672         if (is_multicast_ether_addr(mgmt->da))
2673                 return RX_DROP_MONITOR;
2674
2675         /* do not return rejected action frames */
2676         if (mgmt->u.action.category & 0x80)
2677                 return RX_DROP_UNUSABLE;
2678
2679         nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2680                                GFP_ATOMIC);
2681         if (nskb) {
2682                 struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
2683
2684                 nmgmt->u.action.category |= 0x80;
2685                 memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
2686                 memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2687
2688                 memset(nskb->cb, 0, sizeof(nskb->cb));
2689
2690                 if (rx->sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE) {
2691                         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(nskb);
2692
2693                         info->flags = IEEE80211_TX_CTL_TX_OFFCHAN |
2694                                       IEEE80211_TX_INTFL_OFFCHAN_TX_OK |
2695                                       IEEE80211_TX_CTL_NO_CCK_RATE;
2696                         if (local->hw.flags & IEEE80211_HW_QUEUE_CONTROL)
2697                                 info->hw_queue =
2698                                         local->hw.offchannel_tx_hw_queue;
2699                 }
2700
2701                 __ieee80211_tx_skb_tid_band(rx->sdata, nskb, 7,
2702                                             status->band);
2703         }
2704         dev_kfree_skb(rx->skb);
2705         return RX_QUEUED;
2706 }
2707
2708 static ieee80211_rx_result debug_noinline
2709 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2710 {
2711         struct ieee80211_sub_if_data *sdata = rx->sdata;
2712         struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2713         __le16 stype;
2714
2715         stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2716
2717         if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2718             sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2719             sdata->vif.type != NL80211_IFTYPE_STATION)
2720                 return RX_DROP_MONITOR;
2721
2722         switch (stype) {
2723         case cpu_to_le16(IEEE80211_STYPE_AUTH):
2724         case cpu_to_le16(IEEE80211_STYPE_BEACON):
2725         case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2726                 /* process for all: mesh, mlme, ibss */
2727                 break;
2728         case cpu_to_le16(IEEE80211_STYPE_ASSOC_RESP):
2729         case cpu_to_le16(IEEE80211_STYPE_REASSOC_RESP):
2730         case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2731         case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2732                 if (is_multicast_ether_addr(mgmt->da) &&
2733                     !is_broadcast_ether_addr(mgmt->da))
2734                         return RX_DROP_MONITOR;
2735
2736                 /* process only for station */
2737                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2738                         return RX_DROP_MONITOR;
2739                 break;
2740         case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2741                 /* process only for ibss and mesh */
2742                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2743                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT)
2744                         return RX_DROP_MONITOR;
2745                 break;
2746         default:
2747                 return RX_DROP_MONITOR;
2748         }
2749
2750         /* queue up frame and kick off work to process it */
2751         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2752         skb_queue_tail(&sdata->skb_queue, rx->skb);
2753         ieee80211_queue_work(&rx->local->hw, &sdata->work);
2754         if (rx->sta)
2755                 rx->sta->rx_packets++;
2756
2757         return RX_QUEUED;
2758 }
2759
2760 /* TODO: use IEEE80211_RX_FRAGMENTED */
2761 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2762                                         struct ieee80211_rate *rate)
2763 {
2764         struct ieee80211_sub_if_data *sdata;
2765         struct ieee80211_local *local = rx->local;
2766         struct sk_buff *skb = rx->skb, *skb2;
2767         struct net_device *prev_dev = NULL;
2768         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2769         int needed_headroom;
2770
2771         /*
2772          * If cooked monitor has been processed already, then
2773          * don't do it again. If not, set the flag.
2774          */
2775         if (rx->flags & IEEE80211_RX_CMNTR)
2776                 goto out_free_skb;
2777         rx->flags |= IEEE80211_RX_CMNTR;
2778
2779         /* If there are no cooked monitor interfaces, just free the SKB */
2780         if (!local->cooked_mntrs)
2781                 goto out_free_skb;
2782
2783         /* room for the radiotap header based on driver features */
2784         needed_headroom = ieee80211_rx_radiotap_space(local, status);
2785
2786         if (skb_headroom(skb) < needed_headroom &&
2787             pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC))
2788                 goto out_free_skb;
2789
2790         /* prepend radiotap information */
2791         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
2792                                          false);
2793
2794         skb_set_mac_header(skb, 0);
2795         skb->ip_summed = CHECKSUM_UNNECESSARY;
2796         skb->pkt_type = PACKET_OTHERHOST;
2797         skb->protocol = htons(ETH_P_802_2);
2798
2799         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2800                 if (!ieee80211_sdata_running(sdata))
2801                         continue;
2802
2803                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2804                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2805                         continue;
2806
2807                 if (prev_dev) {
2808                         skb2 = skb_clone(skb, GFP_ATOMIC);
2809                         if (skb2) {
2810                                 skb2->dev = prev_dev;
2811                                 netif_receive_skb(skb2);
2812                         }
2813                 }
2814
2815                 prev_dev = sdata->dev;
2816                 sdata->dev->stats.rx_packets++;
2817                 sdata->dev->stats.rx_bytes += skb->len;
2818         }
2819
2820         if (prev_dev) {
2821                 skb->dev = prev_dev;
2822                 netif_receive_skb(skb);
2823                 return;
2824         }
2825
2826  out_free_skb:
2827         dev_kfree_skb(skb);
2828 }
2829
2830 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
2831                                          ieee80211_rx_result res)
2832 {
2833         switch (res) {
2834         case RX_DROP_MONITOR:
2835                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2836                 if (rx->sta)
2837                         rx->sta->rx_dropped++;
2838                 /* fall through */
2839         case RX_CONTINUE: {
2840                 struct ieee80211_rate *rate = NULL;
2841                 struct ieee80211_supported_band *sband;
2842                 struct ieee80211_rx_status *status;
2843
2844                 status = IEEE80211_SKB_RXCB((rx->skb));
2845
2846                 sband = rx->local->hw.wiphy->bands[status->band];
2847                 if (!(status->flag & RX_FLAG_HT) &&
2848                     !(status->flag & RX_FLAG_VHT))
2849                         rate = &sband->bitrates[status->rate_idx];
2850
2851                 ieee80211_rx_cooked_monitor(rx, rate);
2852                 break;
2853                 }
2854         case RX_DROP_UNUSABLE:
2855                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2856                 if (rx->sta)
2857                         rx->sta->rx_dropped++;
2858                 dev_kfree_skb(rx->skb);
2859                 break;
2860         case RX_QUEUED:
2861                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
2862                 break;
2863         }
2864 }
2865
2866 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
2867                                   struct sk_buff_head *frames)
2868 {
2869         ieee80211_rx_result res = RX_DROP_MONITOR;
2870         struct sk_buff *skb;
2871
2872 #define CALL_RXH(rxh)                   \
2873         do {                            \
2874                 res = rxh(rx);          \
2875                 if (res != RX_CONTINUE) \
2876                         goto rxh_next;  \
2877         } while (0);
2878
2879         spin_lock_bh(&rx->local->rx_path_lock);
2880
2881         while ((skb = __skb_dequeue(frames))) {
2882                 /*
2883                  * all the other fields are valid across frames
2884                  * that belong to an aMPDU since they are on the
2885                  * same TID from the same station
2886                  */
2887                 rx->skb = skb;
2888
2889                 CALL_RXH(ieee80211_rx_h_decrypt)
2890                 CALL_RXH(ieee80211_rx_h_check_more_data)
2891                 CALL_RXH(ieee80211_rx_h_uapsd_and_pspoll)
2892                 CALL_RXH(ieee80211_rx_h_sta_process)
2893                 CALL_RXH(ieee80211_rx_h_defragment)
2894                 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2895                 /* must be after MMIC verify so header is counted in MPDU mic */
2896 #ifdef CONFIG_MAC80211_MESH
2897                 if (ieee80211_vif_is_mesh(&rx->sdata->vif))
2898                         CALL_RXH(ieee80211_rx_h_mesh_fwding);
2899 #endif
2900                 CALL_RXH(ieee80211_rx_h_amsdu)
2901                 CALL_RXH(ieee80211_rx_h_data)
2902
2903                 /* special treatment -- needs the queue */
2904                 res = ieee80211_rx_h_ctrl(rx, frames);
2905                 if (res != RX_CONTINUE)
2906                         goto rxh_next;
2907
2908                 CALL_RXH(ieee80211_rx_h_mgmt_check)
2909                 CALL_RXH(ieee80211_rx_h_action)
2910                 CALL_RXH(ieee80211_rx_h_userspace_mgmt)
2911                 CALL_RXH(ieee80211_rx_h_action_return)
2912                 CALL_RXH(ieee80211_rx_h_mgmt)
2913
2914  rxh_next:
2915                 ieee80211_rx_handlers_result(rx, res);
2916
2917 #undef CALL_RXH
2918         }
2919
2920         spin_unlock_bh(&rx->local->rx_path_lock);
2921 }
2922
2923 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
2924 {
2925         struct sk_buff_head reorder_release;
2926         ieee80211_rx_result res = RX_DROP_MONITOR;
2927
2928         __skb_queue_head_init(&reorder_release);
2929
2930 #define CALL_RXH(rxh)                   \
2931         do {                            \
2932                 res = rxh(rx);          \
2933                 if (res != RX_CONTINUE) \
2934                         goto rxh_next;  \
2935         } while (0);
2936
2937         CALL_RXH(ieee80211_rx_h_check)
2938
2939         ieee80211_rx_reorder_ampdu(rx, &reorder_release);
2940
2941         ieee80211_rx_handlers(rx, &reorder_release);
2942         return;
2943
2944  rxh_next:
2945         ieee80211_rx_handlers_result(rx, res);
2946
2947 #undef CALL_RXH
2948 }
2949
2950 /*
2951  * This function makes calls into the RX path, therefore
2952  * it has to be invoked under RCU read lock.
2953  */
2954 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
2955 {
2956         struct sk_buff_head frames;
2957         struct ieee80211_rx_data rx = {
2958                 .sta = sta,
2959                 .sdata = sta->sdata,
2960                 .local = sta->local,
2961                 /* This is OK -- must be QoS data frame */
2962                 .security_idx = tid,
2963                 .seqno_idx = tid,
2964                 .flags = 0,
2965         };
2966         struct tid_ampdu_rx *tid_agg_rx;
2967
2968         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
2969         if (!tid_agg_rx)
2970                 return;
2971
2972         __skb_queue_head_init(&frames);
2973
2974         spin_lock(&tid_agg_rx->reorder_lock);
2975         ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx, &frames);
2976         spin_unlock(&tid_agg_rx->reorder_lock);
2977
2978         ieee80211_rx_handlers(&rx, &frames);
2979 }
2980
2981 /* main receive path */
2982
2983 static int prepare_for_handlers(struct ieee80211_rx_data *rx,
2984                                 struct ieee80211_hdr *hdr)
2985 {
2986         struct ieee80211_sub_if_data *sdata = rx->sdata;
2987         struct sk_buff *skb = rx->skb;
2988         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2989         u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2990         int multicast = is_multicast_ether_addr(hdr->addr1);
2991
2992         switch (sdata->vif.type) {
2993         case NL80211_IFTYPE_STATION:
2994                 if (!bssid && !sdata->u.mgd.use_4addr)
2995                         return 0;
2996                 if (!multicast &&
2997                     !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
2998                         if (!(sdata->dev->flags & IFF_PROMISC) ||
2999                             sdata->u.mgd.use_4addr)
3000                                 return 0;
3001                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3002                 }
3003                 break;
3004         case NL80211_IFTYPE_ADHOC:
3005                 if (!bssid)
3006                         return 0;
3007                 if (ether_addr_equal(sdata->vif.addr, hdr->addr2) ||
3008                     ether_addr_equal(sdata->u.ibss.bssid, hdr->addr2))
3009                         return 0;
3010                 if (ieee80211_is_beacon(hdr->frame_control)) {
3011                         return 1;
3012                 } else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
3013                         return 0;
3014                 } else if (!multicast &&
3015                            !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
3016                         if (!(sdata->dev->flags & IFF_PROMISC))
3017                                 return 0;
3018                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3019                 } else if (!rx->sta) {
3020                         int rate_idx;
3021                         if (status->flag & (RX_FLAG_HT | RX_FLAG_VHT))
3022                                 rate_idx = 0; /* TODO: HT/VHT rates */
3023                         else
3024                                 rate_idx = status->rate_idx;
3025                         ieee80211_ibss_rx_no_sta(sdata, bssid, hdr->addr2,
3026                                                  BIT(rate_idx));
3027                 }
3028                 break;
3029         case NL80211_IFTYPE_MESH_POINT:
3030                 if (!multicast &&
3031                     !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
3032                         if (!(sdata->dev->flags & IFF_PROMISC))
3033                                 return 0;
3034
3035                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3036                 }
3037                 break;
3038         case NL80211_IFTYPE_AP_VLAN:
3039         case NL80211_IFTYPE_AP:
3040                 if (!bssid) {
3041                         if (!ether_addr_equal(sdata->vif.addr, hdr->addr1))
3042                                 return 0;
3043                 } else if (!ieee80211_bssid_match(bssid, sdata->vif.addr)) {
3044                         /*
3045                          * Accept public action frames even when the
3046                          * BSSID doesn't match, this is used for P2P
3047                          * and location updates. Note that mac80211
3048                          * itself never looks at these frames.
3049                          */
3050                         if (!multicast &&
3051                             !ether_addr_equal(sdata->vif.addr, hdr->addr1))
3052                                 return 0;
3053                         if (ieee80211_is_public_action(hdr, skb->len))
3054                                 return 1;
3055                         if (!ieee80211_is_beacon(hdr->frame_control))
3056                                 return 0;
3057                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3058                 }
3059                 break;
3060         case NL80211_IFTYPE_WDS:
3061                 if (bssid || !ieee80211_is_data(hdr->frame_control))
3062                         return 0;
3063                 if (!ether_addr_equal(sdata->u.wds.remote_addr, hdr->addr2))
3064                         return 0;
3065                 break;
3066         case NL80211_IFTYPE_P2P_DEVICE:
3067                 if (!ieee80211_is_public_action(hdr, skb->len) &&
3068                     !ieee80211_is_probe_req(hdr->frame_control) &&
3069                     !ieee80211_is_probe_resp(hdr->frame_control) &&
3070                     !ieee80211_is_beacon(hdr->frame_control))
3071                         return 0;
3072                 if (!ether_addr_equal(sdata->vif.addr, hdr->addr1) &&
3073                     !multicast)
3074                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3075                 break;
3076         default:
3077                 /* should never get here */
3078                 WARN_ON_ONCE(1);
3079                 break;
3080         }
3081
3082         return 1;
3083 }
3084
3085 /*
3086  * This function returns whether or not the SKB
3087  * was destined for RX processing or not, which,
3088  * if consume is true, is equivalent to whether
3089  * or not the skb was consumed.
3090  */
3091 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
3092                                             struct sk_buff *skb, bool consume)
3093 {
3094         struct ieee80211_local *local = rx->local;
3095         struct ieee80211_sub_if_data *sdata = rx->sdata;
3096         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3097         struct ieee80211_hdr *hdr = (void *)skb->data;
3098         int prepares;
3099
3100         rx->skb = skb;
3101         status->rx_flags |= IEEE80211_RX_RA_MATCH;
3102         prepares = prepare_for_handlers(rx, hdr);
3103
3104         if (!prepares)
3105                 return false;
3106
3107         if (!consume) {
3108                 skb = skb_copy(skb, GFP_ATOMIC);
3109                 if (!skb) {
3110                         if (net_ratelimit())
3111                                 wiphy_debug(local->hw.wiphy,
3112                                         "failed to copy skb for %s\n",
3113                                         sdata->name);
3114                         return true;
3115                 }
3116
3117                 rx->skb = skb;
3118         }
3119
3120         ieee80211_invoke_rx_handlers(rx);
3121         return true;
3122 }
3123
3124 /*
3125  * This is the actual Rx frames handler. as it blongs to Rx path it must
3126  * be called with rcu_read_lock protection.
3127  */
3128 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
3129                                          struct sk_buff *skb)
3130 {
3131         struct ieee80211_local *local = hw_to_local(hw);
3132         struct ieee80211_sub_if_data *sdata;
3133         struct ieee80211_hdr *hdr;
3134         __le16 fc;
3135         struct ieee80211_rx_data rx;
3136         struct ieee80211_sub_if_data *prev;
3137         struct sta_info *sta, *tmp, *prev_sta;
3138         int err = 0;
3139
3140         fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
3141         memset(&rx, 0, sizeof(rx));
3142         rx.skb = skb;
3143         rx.local = local;
3144
3145         if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
3146                 local->dot11ReceivedFragmentCount++;
3147
3148         if (ieee80211_is_mgmt(fc)) {
3149                 /* drop frame if too short for header */
3150                 if (skb->len < ieee80211_hdrlen(fc))
3151                         err = -ENOBUFS;
3152                 else
3153                         err = skb_linearize(skb);
3154         } else {
3155                 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
3156         }
3157
3158         if (err) {
3159                 dev_kfree_skb(skb);
3160                 return;
3161         }
3162
3163         hdr = (struct ieee80211_hdr *)skb->data;
3164         ieee80211_parse_qos(&rx);
3165         ieee80211_verify_alignment(&rx);
3166
3167         if (unlikely(ieee80211_is_probe_resp(hdr->frame_control) ||
3168                      ieee80211_is_beacon(hdr->frame_control)))
3169                 ieee80211_scan_rx(local, skb);
3170
3171         if (ieee80211_is_data(fc)) {
3172                 prev_sta = NULL;
3173
3174                 for_each_sta_info(local, hdr->addr2, sta, tmp) {
3175                         if (!prev_sta) {
3176                                 prev_sta = sta;
3177                                 continue;
3178                         }
3179
3180                         rx.sta = prev_sta;
3181                         rx.sdata = prev_sta->sdata;
3182                         ieee80211_prepare_and_rx_handle(&rx, skb, false);
3183
3184                         prev_sta = sta;
3185                 }
3186
3187                 if (prev_sta) {
3188                         rx.sta = prev_sta;
3189                         rx.sdata = prev_sta->sdata;
3190
3191                         if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
3192                                 return;
3193                         goto out;
3194                 }
3195         }
3196
3197         prev = NULL;
3198
3199         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
3200                 if (!ieee80211_sdata_running(sdata))
3201                         continue;
3202
3203                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
3204                     sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
3205                         continue;
3206
3207                 /*
3208                  * frame is destined for this interface, but if it's
3209                  * not also for the previous one we handle that after
3210                  * the loop to avoid copying the SKB once too much
3211                  */
3212
3213                 if (!prev) {
3214                         prev = sdata;
3215                         continue;
3216                 }
3217
3218                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
3219                 rx.sdata = prev;
3220                 ieee80211_prepare_and_rx_handle(&rx, skb, false);
3221
3222                 prev = sdata;
3223         }
3224
3225         if (prev) {
3226                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
3227                 rx.sdata = prev;
3228
3229                 if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
3230                         return;
3231         }
3232
3233  out:
3234         dev_kfree_skb(skb);
3235 }
3236
3237 /*
3238  * This is the receive path handler. It is called by a low level driver when an
3239  * 802.11 MPDU is received from the hardware.
3240  */
3241 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
3242 {
3243         struct ieee80211_local *local = hw_to_local(hw);
3244         struct ieee80211_rate *rate = NULL;
3245         struct ieee80211_supported_band *sband;
3246         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3247
3248         WARN_ON_ONCE(softirq_count() == 0);
3249
3250         if (WARN_ON(status->band >= IEEE80211_NUM_BANDS))
3251                 goto drop;
3252
3253         sband = local->hw.wiphy->bands[status->band];
3254         if (WARN_ON(!sband))
3255                 goto drop;
3256
3257         /*
3258          * If we're suspending, it is possible although not too likely
3259          * that we'd be receiving frames after having already partially
3260          * quiesced the stack. We can't process such frames then since
3261          * that might, for example, cause stations to be added or other
3262          * driver callbacks be invoked.
3263          */
3264         if (unlikely(local->quiescing || local->suspended))
3265                 goto drop;
3266
3267         /* We might be during a HW reconfig, prevent Rx for the same reason */
3268         if (unlikely(local->in_reconfig))
3269                 goto drop;
3270
3271         /*
3272          * The same happens when we're not even started,
3273          * but that's worth a warning.
3274          */
3275         if (WARN_ON(!local->started))
3276                 goto drop;
3277
3278         if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
3279                 /*
3280                  * Validate the rate, unless a PLCP error means that
3281                  * we probably can't have a valid rate here anyway.
3282                  */
3283
3284                 if (status->flag & RX_FLAG_HT) {
3285                         /*
3286                          * rate_idx is MCS index, which can be [0-76]
3287                          * as documented on:
3288                          *
3289                          * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
3290                          *
3291                          * Anything else would be some sort of driver or
3292                          * hardware error. The driver should catch hardware
3293                          * errors.
3294                          */
3295                         if (WARN(status->rate_idx > 76,
3296                                  "Rate marked as an HT rate but passed "
3297                                  "status->rate_idx is not "
3298                                  "an MCS index [0-76]: %d (0x%02x)\n",
3299                                  status->rate_idx,
3300                                  status->rate_idx))
3301                                 goto drop;
3302                 } else if (status->flag & RX_FLAG_VHT) {
3303                         if (WARN_ONCE(status->rate_idx > 9 ||
3304                                       !status->vht_nss ||
3305                                       status->vht_nss > 8,
3306                                       "Rate marked as a VHT rate but data is invalid: MCS: %d, NSS: %d\n",
3307                                       status->rate_idx, status->vht_nss))
3308                                 goto drop;
3309                 } else {
3310                         if (WARN_ON(status->rate_idx >= sband->n_bitrates))
3311                                 goto drop;
3312                         rate = &sband->bitrates[status->rate_idx];
3313                 }
3314         }
3315
3316         status->rx_flags = 0;
3317
3318         /*
3319          * key references and virtual interfaces are protected using RCU
3320          * and this requires that we are in a read-side RCU section during
3321          * receive processing
3322          */
3323         rcu_read_lock();
3324
3325         /*
3326          * Frames with failed FCS/PLCP checksum are not returned,
3327          * all other frames are returned without radiotap header
3328          * if it was previously present.
3329          * Also, frames with less than 16 bytes are dropped.
3330          */
3331         skb = ieee80211_rx_monitor(local, skb, rate);
3332         if (!skb) {
3333                 rcu_read_unlock();
3334                 return;
3335         }
3336
3337         ieee80211_tpt_led_trig_rx(local,
3338                         ((struct ieee80211_hdr *)skb->data)->frame_control,
3339                         skb->len);
3340         __ieee80211_rx_handle_packet(hw, skb);
3341
3342         rcu_read_unlock();
3343
3344         return;
3345  drop:
3346         kfree_skb(skb);
3347 }
3348 EXPORT_SYMBOL(ieee80211_rx);
3349
3350 /* This is a version of the rx handler that can be called from hard irq
3351  * context. Post the skb on the queue and schedule the tasklet */
3352 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
3353 {
3354         struct ieee80211_local *local = hw_to_local(hw);
3355
3356         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
3357
3358         skb->pkt_type = IEEE80211_RX_MSG;
3359         skb_queue_tail(&local->skb_queue, skb);
3360         tasklet_schedule(&local->tasklet);
3361 }
3362 EXPORT_SYMBOL(ieee80211_rx_irqsafe);