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                 goto dont_reorder;
 869
 870         /*
 871          * filter the QoS data rx stream according to
 872          * STA/TID and check if this STA/TID is on aggregation
 873          */
 874
 875         if (!sta)
 876                 goto dont_reorder;
 877
 878         ack_policy = *ieee80211_get_qos_ctl(hdr) &
 879                      IEEE80211_QOS_CTL_ACK_POLICY_MASK;
 880         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
 881
 882         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
 883         if (!tid_agg_rx)
 884                 goto dont_reorder;
 885
 886         /* qos null data frames are excluded */
 887         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
 888                 goto dont_reorder;
 889
 890         /* not part of a BA session */
 891         if (ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
 892             ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_NORMAL)
 893                 goto dont_reorder;
 894
 895         /* not actually part of this BA session */
 896         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
 897                 goto dont_reorder;
 898
 899         /* new, potentially un-ordered, ampdu frame - process it */
 900
 901         /* reset session timer */
 902         if (tid_agg_rx->timeout)
 903                 tid_agg_rx->last_rx = jiffies;
 904
 905         /* if this mpdu is fragmented - terminate rx aggregation session */
 906         sc = le16_to_cpu(hdr->seq_ctrl);
 907         if (sc & IEEE80211_SCTL_FRAG) {
 908                 skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
 909                 skb_queue_tail(&rx->sdata->skb_queue, skb);
 910                 ieee80211_queue_work(&local->hw, &rx->sdata->work);
 911                 return;
 912         }
 913
 914         /*
 915          * No locking needed -- we will only ever process one
 916          * RX packet at a time, and thus own tid_agg_rx. All
 917          * other code manipulating it needs to (and does) make
 918          * sure that we cannot get to it any more before doing
 919          * anything with it.
 920          */
 921         if (ieee80211_sta_manage_reorder_buf(rx->sdata, tid_agg_rx, skb,
 922                                              frames))
 923                 return;
 924
 925  dont_reorder:
 926         __skb_queue_tail(frames, skb);
 927 }
 928
 929 static ieee80211_rx_result debug_noinline
 930 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
 931 {
 932         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 933         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 934
 935         /* Drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.2.9) */
 936         if (rx->sta && !is_multicast_ether_addr(hdr->addr1)) {
 937                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
 938                              rx->sta->last_seq_ctrl[rx->seqno_idx] ==
 939                              hdr->seq_ctrl)) {
 940                         if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
 941                                 rx->local->dot11FrameDuplicateCount++;
 942                                 rx->sta->num_duplicates++;
 943                         }
 944                         return RX_DROP_UNUSABLE;
 945                 } else
 946                         rx->sta->last_seq_ctrl[rx->seqno_idx] = hdr->seq_ctrl;
 947         }
 948
 949         if (unlikely(rx->skb->len < 16)) {
 950                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 951                 return RX_DROP_MONITOR;
 952         }
 953
 954         /* Drop disallowed frame classes based on STA auth/assoc state;
 955          * IEEE 802.11, Chap 5.5.
 956          *
 957          * mac80211 filters only based on association state, i.e. it drops
 958          * Class 3 frames from not associated stations. hostapd sends
 959          * deauth/disassoc frames when needed. In addition, hostapd is
 960          * responsible for filtering on both auth and assoc states.
 961          */
 962
 963         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
 964                 return ieee80211_rx_mesh_check(rx);
 965
 966         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
 967                       ieee80211_is_pspoll(hdr->frame_control)) &&
 968                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
 969                      rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
 970                      (!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_ASSOC)))) {
 971                 /*
 972                  * accept port control frames from the AP even when it's not
 973                  * yet marked ASSOC to prevent a race where we don't set the
 974                  * assoc bit quickly enough before it sends the first frame
 975                  */
 976                 if (rx->sta && rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
 977                     ieee80211_is_data_present(hdr->frame_control)) {
 978                         unsigned int hdrlen;
 979                         __be16 ethertype;
 980
 981                         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 982
 983                         if (rx->skb->len < hdrlen + 8)
 984                                 return RX_DROP_MONITOR;
 985
 986                         skb_copy_bits(rx->skb, hdrlen + 6, &ethertype, 2);
 987                         if (ethertype == rx->sdata->control_port_protocol)
 988                                 return RX_CONTINUE;
 989                 }
 990
 991                 if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
 992                     cfg80211_rx_spurious_frame(rx->sdata->dev,
 993                                                hdr->addr2,
 994                                                GFP_ATOMIC))
 995                         return RX_DROP_UNUSABLE;
 996
 997                 return RX_DROP_MONITOR;
 998         }
 999
1000         return RX_CONTINUE;
1001 }
1002
1003
1004 static ieee80211_rx_result debug_noinline
1005 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
1006 {
1007         struct sk_buff *skb = rx->skb;
1008         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1009         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1010         int keyidx;
1011         int hdrlen;
1012         ieee80211_rx_result result = RX_DROP_UNUSABLE;
1013         struct ieee80211_key *sta_ptk = NULL;
1014         int mmie_keyidx = -1;
1015         __le16 fc;
1016
1017         /*
1018          * Key selection 101
1019          *
1020          * There are four types of keys:
1021          *  - GTK (group keys)
1022          *  - IGTK (group keys for management frames)
1023          *  - PTK (pairwise keys)
1024          *  - STK (station-to-station pairwise keys)
1025          *
1026          * When selecting a key, we have to distinguish between multicast
1027          * (including broadcast) and unicast frames, the latter can only
1028          * use PTKs and STKs while the former always use GTKs and IGTKs.
1029          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
1030          * unicast frames can also use key indices like GTKs. Hence, if we
1031          * don't have a PTK/STK we check the key index for a WEP key.
1032          *
1033          * Note that in a regular BSS, multicast frames are sent by the
1034          * AP only, associated stations unicast the frame to the AP first
1035          * which then multicasts it on their behalf.
1036          *
1037          * There is also a slight problem in IBSS mode: GTKs are negotiated
1038          * with each station, that is something we don't currently handle.
1039          * The spec seems to expect that one negotiates the same key with
1040          * every station but there's no such requirement; VLANs could be
1041          * possible.
1042          */
1043
1044         /*
1045          * No point in finding a key and decrypting if the frame is neither
1046          * addressed to us nor a multicast frame.
1047          */
1048         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1049                 return RX_CONTINUE;
1050
1051         /* start without a key */
1052         rx->key = NULL;
1053
1054         if (rx->sta)
1055                 sta_ptk = rcu_dereference(rx->sta->ptk);
1056
1057         fc = hdr->frame_control;
1058
1059         if (!ieee80211_has_protected(fc))
1060                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
1061
1062         if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
1063                 rx->key = sta_ptk;
1064                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1065                     (status->flag & RX_FLAG_IV_STRIPPED))
1066                         return RX_CONTINUE;
1067                 /* Skip decryption if the frame is not protected. */
1068                 if (!ieee80211_has_protected(fc))
1069                         return RX_CONTINUE;
1070         } else if (mmie_keyidx >= 0) {
1071                 /* Broadcast/multicast robust management frame / BIP */
1072                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1073                     (status->flag & RX_FLAG_IV_STRIPPED))
1074                         return RX_CONTINUE;
1075
1076                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
1077                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
1078                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
1079                 if (rx->sta)
1080                         rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
1081                 if (!rx->key)
1082                         rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
1083         } else if (!ieee80211_has_protected(fc)) {
1084                 /*
1085                  * The frame was not protected, so skip decryption. However, we
1086                  * need to set rx->key if there is a key that could have been
1087                  * used so that the frame may be dropped if encryption would
1088                  * have been expected.
1089                  */
1090                 struct ieee80211_key *key = NULL;
1091                 struct ieee80211_sub_if_data *sdata = rx->sdata;
1092                 int i;
1093
1094                 if (ieee80211_is_mgmt(fc) &&
1095                     is_multicast_ether_addr(hdr->addr1) &&
1096                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
1097                         rx->key = key;
1098                 else {
1099                         if (rx->sta) {
1100                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1101                                         key = rcu_dereference(rx->sta->gtk[i]);
1102                                         if (key)
1103                                                 break;
1104                                 }
1105                         }
1106                         if (!key) {
1107                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1108                                         key = rcu_dereference(sdata->keys[i]);
1109                                         if (key)
1110                                                 break;
1111                                 }
1112                         }
1113                         if (key)
1114                                 rx->key = key;
1115                 }
1116                 return RX_CONTINUE;
1117         } else {
1118                 u8 keyid;
1119                 /*
1120                  * The device doesn't give us the IV so we won't be
1121                  * able to look up the key. That's ok though, we
1122                  * don't need to decrypt the frame, we just won't
1123                  * be able to keep statistics accurate.
1124                  * Except for key threshold notifications, should
1125                  * we somehow allow the driver to tell us which key
1126                  * the hardware used if this flag is set?
1127                  */
1128                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1129                     (status->flag & RX_FLAG_IV_STRIPPED))
1130                         return RX_CONTINUE;
1131
1132                 hdrlen = ieee80211_hdrlen(fc);
1133
1134                 if (rx->skb->len < 8 + hdrlen)
1135                         return RX_DROP_UNUSABLE; /* TODO: count this? */
1136
1137                 /*
1138                  * no need to call ieee80211_wep_get_keyidx,
1139                  * it verifies a bunch of things we've done already
1140                  */
1141                 skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
1142                 keyidx = keyid >> 6;
1143
1144                 /* check per-station GTK first, if multicast packet */
1145                 if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
1146                         rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
1147
1148                 /* if not found, try default key */
1149                 if (!rx->key) {
1150                         rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
1151
1152                         /*
1153                          * RSNA-protected unicast frames should always be
1154                          * sent with pairwise or station-to-station keys,
1155                          * but for WEP we allow using a key index as well.
1156                          */
1157                         if (rx->key &&
1158                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1159                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1160                             !is_multicast_ether_addr(hdr->addr1))
1161                                 rx->key = NULL;
1162                 }
1163         }
1164
1165         if (rx->key) {
1166                 if (unlikely(rx->key->flags & KEY_FLAG_TAINTED))
1167                         return RX_DROP_MONITOR;
1168
1169                 rx->key->tx_rx_count++;
1170                 /* TODO: add threshold stuff again */
1171         } else {
1172                 return RX_DROP_MONITOR;
1173         }
1174
1175         switch (rx->key->conf.cipher) {
1176         case WLAN_CIPHER_SUITE_WEP40:
1177         case WLAN_CIPHER_SUITE_WEP104:
1178                 result = ieee80211_crypto_wep_decrypt(rx);
1179                 break;
1180         case WLAN_CIPHER_SUITE_TKIP:
1181                 result = ieee80211_crypto_tkip_decrypt(rx);
1182                 break;
1183         case WLAN_CIPHER_SUITE_CCMP:
1184                 result = ieee80211_crypto_ccmp_decrypt(rx);
1185                 break;
1186         case WLAN_CIPHER_SUITE_AES_CMAC:
1187                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
1188                 break;
1189         default:
1190                 /*
1191                  * We can reach here only with HW-only algorithms
1192                  * but why didn't it decrypt the frame?!
1193                  */
1194                 return RX_DROP_UNUSABLE;
1195         }
1196
1197         /* the hdr variable is invalid after the decrypt handlers */
1198
1199         /* either the frame has been decrypted or will be dropped */
1200         status->flag |= RX_FLAG_DECRYPTED;
1201
1202         return result;
1203 }
1204
1205 static ieee80211_rx_result debug_noinline
1206 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1207 {
1208         struct ieee80211_local *local;
1209         struct ieee80211_hdr *hdr;
1210         struct sk_buff *skb;
1211
1212         local = rx->local;
1213         skb = rx->skb;
1214         hdr = (struct ieee80211_hdr *) skb->data;
1215
1216         if (!local->pspolling)
1217                 return RX_CONTINUE;
1218
1219         if (!ieee80211_has_fromds(hdr->frame_control))
1220                 /* this is not from AP */
1221                 return RX_CONTINUE;
1222
1223         if (!ieee80211_is_data(hdr->frame_control))
1224                 return RX_CONTINUE;
1225
1226         if (!ieee80211_has_moredata(hdr->frame_control)) {
1227                 /* AP has no more frames buffered for us */
1228                 local->pspolling = false;
1229                 return RX_CONTINUE;
1230         }
1231
1232         /* more data bit is set, let's request a new frame from the AP */
1233         ieee80211_send_pspoll(local, rx->sdata);
1234
1235         return RX_CONTINUE;
1236 }
1237
1238 static void sta_ps_start(struct sta_info *sta)
1239 {
1240         struct ieee80211_sub_if_data *sdata = sta->sdata;
1241         struct ieee80211_local *local = sdata->local;
1242         struct ps_data *ps;
1243
1244         if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
1245             sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1246                 ps = &sdata->bss->ps;
1247         else
1248                 return;
1249
1250         atomic_inc(&ps->num_sta_ps);
1251         set_sta_flag(sta, WLAN_STA_PS_STA);
1252         if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
1253                 drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1254         ps_dbg(sdata, "STA %pM aid %d enters power save mode\n",
1255                sta->sta.addr, sta->sta.aid);
1256 }
1257
1258 static void sta_ps_end(struct sta_info *sta)
1259 {
1260         ps_dbg(sta->sdata, "STA %pM aid %d exits power save mode\n",
1261                sta->sta.addr, sta->sta.aid);
1262
1263         if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) {
1264                 ps_dbg(sta->sdata, "STA %pM aid %d driver-ps-blocked\n",
1265                        sta->sta.addr, sta->sta.aid);
1266                 return;
1267         }
1268
1269         ieee80211_sta_ps_deliver_wakeup(sta);
1270 }
1271
1272 int ieee80211_sta_ps_transition(struct ieee80211_sta *sta, bool start)
1273 {
1274         struct sta_info *sta_inf = container_of(sta, struct sta_info, sta);
1275         bool in_ps;
1276
1277         WARN_ON(!(sta_inf->local->hw.flags & IEEE80211_HW_AP_LINK_PS));
1278
1279         /* Don't let the same PS state be set twice */
1280         in_ps = test_sta_flag(sta_inf, WLAN_STA_PS_STA);
1281         if ((start && in_ps) || (!start && !in_ps))
1282                 return -EINVAL;
1283
1284         if (start)
1285                 sta_ps_start(sta_inf);
1286         else
1287                 sta_ps_end(sta_inf);
1288
1289         return 0;
1290 }
1291 EXPORT_SYMBOL(ieee80211_sta_ps_transition);
1292
1293 static ieee80211_rx_result debug_noinline
1294 ieee80211_rx_h_uapsd_and_pspoll(struct ieee80211_rx_data *rx)
1295 {
1296         struct ieee80211_sub_if_data *sdata = rx->sdata;
1297         struct ieee80211_hdr *hdr = (void *)rx->skb->data;
1298         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1299         int tid, ac;
1300
1301         if (!rx->sta || !(status->rx_flags & IEEE80211_RX_RA_MATCH))
1302                 return RX_CONTINUE;
1303
1304         if (sdata->vif.type != NL80211_IFTYPE_AP &&
1305             sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
1306                 return RX_CONTINUE;
1307
1308         /*
1309          * The device handles station powersave, so don't do anything about
1310          * uAPSD and PS-Poll frames (the latter shouldn't even come up from
1311          * it to mac80211 since they're handled.)
1312          */
1313         if (sdata->local->hw.flags & IEEE80211_HW_AP_LINK_PS)
1314                 return RX_CONTINUE;
1315
1316         /*
1317          * Don't do anything if the station isn't already asleep. In
1318          * the uAPSD case, the station will probably be marked asleep,
1319          * in the PS-Poll case the station must be confused ...
1320          */
1321         if (!test_sta_flag(rx->sta, WLAN_STA_PS_STA))
1322                 return RX_CONTINUE;
1323
1324         if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) {
1325                 if (!test_sta_flag(rx->sta, WLAN_STA_SP)) {
1326                         if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1327                                 ieee80211_sta_ps_deliver_poll_response(rx->sta);
1328                         else
1329                                 set_sta_flag(rx->sta, WLAN_STA_PSPOLL);
1330                 }
1331
1332                 /* Free PS Poll skb here instead of returning RX_DROP that would
1333                  * count as an dropped frame. */
1334                 dev_kfree_skb(rx->skb);
1335
1336                 return RX_QUEUED;
1337         } else if (!ieee80211_has_morefrags(hdr->frame_control) &&
1338                    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1339                    ieee80211_has_pm(hdr->frame_control) &&
1340                    (ieee80211_is_data_qos(hdr->frame_control) ||
1341                     ieee80211_is_qos_nullfunc(hdr->frame_control))) {
1342                 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
1343                 ac = ieee802_1d_to_ac[tid & 7];
1344
1345                 /*
1346                  * If this AC is not trigger-enabled do nothing.
1347                  *
1348                  * NB: This could/should check a separate bitmap of trigger-
1349                  * enabled queues, but for now we only implement uAPSD w/o
1350                  * TSPEC changes to the ACs, so they're always the same.
1351                  */
1352                 if (!(rx->sta->sta.uapsd_queues & BIT(ac)))
1353                         return RX_CONTINUE;
1354
1355                 /* if we are in a service period, do nothing */
1356                 if (test_sta_flag(rx->sta, WLAN_STA_SP))
1357                         return RX_CONTINUE;
1358
1359                 if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1360                         ieee80211_sta_ps_deliver_uapsd(rx->sta);
1361                 else
1362                         set_sta_flag(rx->sta, WLAN_STA_UAPSD);
1363         }
1364
1365         return RX_CONTINUE;
1366 }
1367
1368 static ieee80211_rx_result debug_noinline
1369 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1370 {
1371         struct sta_info *sta = rx->sta;
1372         struct sk_buff *skb = rx->skb;
1373         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1374         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1375
1376         if (!sta)
1377                 return RX_CONTINUE;
1378
1379         /*
1380          * Update last_rx only for IBSS packets which are for the current
1381          * BSSID and for station already AUTHORIZED to avoid keeping the
1382          * current IBSS network alive in cases where other STAs start
1383          * using different BSSID. This will also give the station another
1384          * chance to restart the authentication/authorization in case
1385          * something went wrong the first time.
1386          */
1387         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1388                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1389                                                 NL80211_IFTYPE_ADHOC);
1390                 if (ether_addr_equal(bssid, rx->sdata->u.ibss.bssid) &&
1391                     test_sta_flag(sta, WLAN_STA_AUTHORIZED)) {
1392                         sta->last_rx = jiffies;
1393                         if (ieee80211_is_data(hdr->frame_control)) {
1394                                 sta->last_rx_rate_idx = status->rate_idx;
1395                                 sta->last_rx_rate_flag = status->flag;
1396                                 sta->last_rx_rate_vht_nss = status->vht_nss;
1397                         }
1398                 }
1399         } else if (!is_multicast_ether_addr(hdr->addr1)) {
1400                 /*
1401                  * Mesh beacons will update last_rx when if they are found to
1402                  * match the current local configuration when processed.
1403                  */
1404                 sta->last_rx = jiffies;
1405                 if (ieee80211_is_data(hdr->frame_control)) {
1406                         sta->last_rx_rate_idx = status->rate_idx;
1407                         sta->last_rx_rate_flag = status->flag;
1408                         sta->last_rx_rate_vht_nss = status->vht_nss;
1409                 }
1410         }
1411
1412         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1413                 return RX_CONTINUE;
1414
1415         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1416                 ieee80211_sta_rx_notify(rx->sdata, hdr);
1417
1418         sta->rx_fragments++;
1419         sta->rx_bytes += rx->skb->len;
1420         if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
1421                 sta->last_signal = status->signal;
1422                 ewma_add(&sta->avg_signal, -status->signal);
1423         }
1424
1425         /*
1426          * Change STA power saving mode only at the end of a frame
1427          * exchange sequence.
1428          */
1429         if (!(sta->local->hw.flags & IEEE80211_HW_AP_LINK_PS) &&
1430             !ieee80211_has_morefrags(hdr->frame_control) &&
1431             !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1432             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1433              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1434                 if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
1435                         /*
1436                          * Ignore doze->wake transitions that are
1437                          * indicated by non-data frames, the standard
1438                          * is unclear here, but for example going to
1439                          * PS mode and then scanning would cause a
1440                          * doze->wake transition for the probe request,
1441                          * and that is clearly undesirable.
1442                          */
1443                         if (ieee80211_is_data(hdr->frame_control) &&
1444                             !ieee80211_has_pm(hdr->frame_control))
1445                                 sta_ps_end(sta);
1446                 } else {
1447                         if (ieee80211_has_pm(hdr->frame_control))
1448                                 sta_ps_start(sta);
1449                 }
1450         }
1451
1452         /* mesh power save support */
1453         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
1454                 ieee80211_mps_rx_h_sta_process(sta, hdr);
1455
1456         /*
1457          * Drop (qos-)data::nullfunc frames silently, since they
1458          * are used only to control station power saving mode.
1459          */
1460         if (ieee80211_is_nullfunc(hdr->frame_control) ||
1461             ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1462                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1463
1464                 /*
1465                  * If we receive a 4-addr nullfunc frame from a STA
1466                  * that was not moved to a 4-addr STA vlan yet send
1467                  * the event to userspace and for older hostapd drop
1468                  * the frame to the monitor interface.
1469                  */
1470                 if (ieee80211_has_a4(hdr->frame_control) &&
1471                     (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1472                      (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1473                       !rx->sdata->u.vlan.sta))) {
1474                         if (!test_and_set_sta_flag(sta, WLAN_STA_4ADDR_EVENT))
1475                                 cfg80211_rx_unexpected_4addr_frame(
1476                                         rx->sdata->dev, sta->sta.addr,
1477                                         GFP_ATOMIC);
1478                         return RX_DROP_MONITOR;
1479                 }
1480                 /*
1481                  * Update counter and free packet here to avoid
1482                  * counting this as a dropped packed.
1483                  */
1484                 sta->rx_packets++;
1485                 dev_kfree_skb(rx->skb);
1486                 return RX_QUEUED;
1487         }
1488
1489         return RX_CONTINUE;
1490 } /* ieee80211_rx_h_sta_process */
1491
1492 static inline struct ieee80211_fragment_entry *
1493 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1494                          unsigned int frag, unsigned int seq, int rx_queue,
1495                          struct sk_buff **skb)
1496 {
1497         struct ieee80211_fragment_entry *entry;
1498
1499         entry = &sdata->fragments[sdata->fragment_next++];
1500         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1501                 sdata->fragment_next = 0;
1502
1503         if (!skb_queue_empty(&entry->skb_list))
1504                 __skb_queue_purge(&entry->skb_list);
1505
1506         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1507         *skb = NULL;
1508         entry->first_frag_time = jiffies;
1509         entry->seq = seq;
1510         entry->rx_queue = rx_queue;
1511         entry->last_frag = frag;
1512         entry->ccmp = 0;
1513         entry->extra_len = 0;
1514
1515         return entry;
1516 }
1517
1518 static inline struct ieee80211_fragment_entry *
1519 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1520                           unsigned int frag, unsigned int seq,
1521                           int rx_queue, struct ieee80211_hdr *hdr)
1522 {
1523         struct ieee80211_fragment_entry *entry;
1524         int i, idx;
1525
1526         idx = sdata->fragment_next;
1527         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1528                 struct ieee80211_hdr *f_hdr;
1529
1530                 idx--;
1531                 if (idx < 0)
1532                         idx = IEEE80211_FRAGMENT_MAX - 1;
1533
1534                 entry = &sdata->fragments[idx];
1535                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1536                     entry->rx_queue != rx_queue ||
1537                     entry->last_frag + 1 != frag)
1538                         continue;
1539
1540                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1541
1542                 /*
1543                  * Check ftype and addresses are equal, else check next fragment
1544                  */
1545                 if (((hdr->frame_control ^ f_hdr->frame_control) &
1546                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1547                     !ether_addr_equal(hdr->addr1, f_hdr->addr1) ||
1548                     !ether_addr_equal(hdr->addr2, f_hdr->addr2))
1549                         continue;
1550
1551                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1552                         __skb_queue_purge(&entry->skb_list);
1553                         continue;
1554                 }
1555                 return entry;
1556         }
1557
1558         return NULL;
1559 }
1560
1561 static ieee80211_rx_result debug_noinline
1562 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1563 {
1564         struct ieee80211_hdr *hdr;
1565         u16 sc;
1566         __le16 fc;
1567         unsigned int frag, seq;
1568         struct ieee80211_fragment_entry *entry;
1569         struct sk_buff *skb;
1570         struct ieee80211_rx_status *status;
1571
1572         hdr = (struct ieee80211_hdr *)rx->skb->data;
1573         fc = hdr->frame_control;
1574
1575         if (ieee80211_is_ctl(fc))
1576                 return RX_CONTINUE;
1577
1578         sc = le16_to_cpu(hdr->seq_ctrl);
1579         frag = sc & IEEE80211_SCTL_FRAG;
1580
1581         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1582                    is_multicast_ether_addr(hdr->addr1))) {
1583                 /* not fragmented */
1584                 goto out;
1585         }
1586         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1587
1588         if (skb_linearize(rx->skb))
1589                 return RX_DROP_UNUSABLE;
1590
1591         /*
1592          *  skb_linearize() might change the skb->data and
1593          *  previously cached variables (in this case, hdr) need to
1594          *  be refreshed with the new data.
1595          */
1596         hdr = (struct ieee80211_hdr *)rx->skb->data;
1597         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1598
1599         if (frag == 0) {
1600                 /* This is the first fragment of a new frame. */
1601                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1602                                                  rx->seqno_idx, &(rx->skb));
1603                 if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP &&
1604                     ieee80211_has_protected(fc)) {
1605                         int queue = rx->security_idx;
1606                         /* Store CCMP PN so that we can verify that the next
1607                          * fragment has a sequential PN value. */
1608                         entry->ccmp = 1;
1609                         memcpy(entry->last_pn,
1610                                rx->key->u.ccmp.rx_pn[queue],
1611                                CCMP_PN_LEN);
1612                 }
1613                 return RX_QUEUED;
1614         }
1615
1616         /* This is a fragment for a frame that should already be pending in
1617          * fragment cache. Add this fragment to the end of the pending entry.
1618          */
1619         entry = ieee80211_reassemble_find(rx->sdata, frag, seq,
1620                                           rx->seqno_idx, hdr);
1621         if (!entry) {
1622                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1623                 return RX_DROP_MONITOR;
1624         }
1625
1626         /* Verify that MPDUs within one MSDU have sequential PN values.
1627          * (IEEE 802.11i, 8.3.3.4.5) */
1628         if (entry->ccmp) {
1629                 int i;
1630                 u8 pn[CCMP_PN_LEN], *rpn;
1631                 int queue;
1632                 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP)
1633                         return RX_DROP_UNUSABLE;
1634                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1635                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1636                         pn[i]++;
1637                         if (pn[i])
1638                                 break;
1639                 }
1640                 queue = rx->security_idx;
1641                 rpn = rx->key->u.ccmp.rx_pn[queue];
1642                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1643                         return RX_DROP_UNUSABLE;
1644                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1645         }
1646
1647         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1648         __skb_queue_tail(&entry->skb_list, rx->skb);
1649         entry->last_frag = frag;
1650         entry->extra_len += rx->skb->len;
1651         if (ieee80211_has_morefrags(fc)) {
1652                 rx->skb = NULL;
1653                 return RX_QUEUED;
1654         }
1655
1656         rx->skb = __skb_dequeue(&entry->skb_list);
1657         if (skb_tailroom(rx->skb) < entry->extra_len) {
1658                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1659                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1660                                               GFP_ATOMIC))) {
1661                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1662                         __skb_queue_purge(&entry->skb_list);
1663                         return RX_DROP_UNUSABLE;
1664                 }
1665         }
1666         while ((skb = __skb_dequeue(&entry->skb_list))) {
1667                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1668                 dev_kfree_skb(skb);
1669         }
1670
1671         /* Complete frame has been reassembled - process it now */
1672         status = IEEE80211_SKB_RXCB(rx->skb);
1673         status->rx_flags |= IEEE80211_RX_FRAGMENTED;
1674
1675  out:
1676         if (rx->sta)
1677                 rx->sta->rx_packets++;
1678         if (is_multicast_ether_addr(hdr->addr1))
1679                 rx->local->dot11MulticastReceivedFrameCount++;
1680         else
1681                 ieee80211_led_rx(rx->local);
1682         return RX_CONTINUE;
1683 }
1684
1685 static int ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1686 {
1687         if (unlikely(!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_AUTHORIZED)))
1688                 return -EACCES;
1689
1690         return 0;
1691 }
1692
1693 static int ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1694 {
1695         struct sk_buff *skb = rx->skb;
1696         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1697
1698         /*
1699          * Pass through unencrypted frames if the hardware has
1700          * decrypted them already.
1701          */
1702         if (status->flag & RX_FLAG_DECRYPTED)
1703                 return 0;
1704
1705         /* Drop unencrypted frames if key is set. */
1706         if (unlikely(!ieee80211_has_protected(fc) &&
1707                      !ieee80211_is_nullfunc(fc) &&
1708                      ieee80211_is_data(fc) &&
1709                      (rx->key || rx->sdata->drop_unencrypted)))
1710                 return -EACCES;
1711
1712         return 0;
1713 }
1714
1715 static int ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1716 {
1717         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1718         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1719         __le16 fc = hdr->frame_control;
1720
1721         /*
1722          * Pass through unencrypted frames if the hardware has
1723          * decrypted them already.
1724          */
1725         if (status->flag & RX_FLAG_DECRYPTED)
1726                 return 0;
1727
1728         if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) {
1729                 if (unlikely(!ieee80211_has_protected(fc) &&
1730                              ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1731                              rx->key)) {
1732                         if (ieee80211_is_deauth(fc))
1733                                 cfg80211_send_unprot_deauth(rx->sdata->dev,
1734                                                             rx->skb->data,
1735                                                             rx->skb->len);
1736                         else if (ieee80211_is_disassoc(fc))
1737                                 cfg80211_send_unprot_disassoc(rx->sdata->dev,
1738                                                               rx->skb->data,
1739                                                               rx->skb->len);
1740                         return -EACCES;
1741                 }
1742                 /* BIP does not use Protected field, so need to check MMIE */
1743                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1744                              ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
1745                         if (ieee80211_is_deauth(fc))
1746                                 cfg80211_send_unprot_deauth(rx->sdata->dev,
1747                                                             rx->skb->data,
1748                                                             rx->skb->len);
1749                         else if (ieee80211_is_disassoc(fc))
1750                                 cfg80211_send_unprot_disassoc(rx->sdata->dev,
1751                                                               rx->skb->data,
1752                                                               rx->skb->len);
1753                         return -EACCES;
1754                 }
1755                 /*
1756                  * When using MFP, Action frames are not allowed prior to
1757                  * having configured keys.
1758                  */
1759                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1760                              ieee80211_is_robust_mgmt_frame(
1761                                      (struct ieee80211_hdr *) rx->skb->data)))
1762                         return -EACCES;
1763         }
1764
1765         return 0;
1766 }
1767
1768 static int
1769 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx, bool *port_control)
1770 {
1771         struct ieee80211_sub_if_data *sdata = rx->sdata;
1772         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1773         bool check_port_control = false;
1774         struct ethhdr *ehdr;
1775         int ret;
1776
1777         *port_control = false;
1778         if (ieee80211_has_a4(hdr->frame_control) &&
1779             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1780                 return -1;
1781
1782         if (sdata->vif.type == NL80211_IFTYPE_STATION &&
1783             !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) {
1784
1785                 if (!sdata->u.mgd.use_4addr)
1786                         return -1;
1787                 else
1788                         check_port_control = true;
1789         }
1790
1791         if (is_multicast_ether_addr(hdr->addr1) &&
1792             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta)
1793                 return -1;
1794
1795         ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1796         if (ret < 0)
1797                 return ret;
1798
1799         ehdr = (struct ethhdr *) rx->skb->data;
1800         if (ehdr->h_proto == rx->sdata->control_port_protocol)
1801                 *port_control = true;
1802         else if (check_port_control)
1803                 return -1;
1804
1805         return 0;
1806 }
1807
1808 /*
1809  * requires that rx->skb is a frame with ethernet header
1810  */
1811 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1812 {
1813         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1814                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1815         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1816
1817         /*
1818          * Allow EAPOL frames to us/the PAE group address regardless
1819          * of whether the frame was encrypted or not.
1820          */
1821         if (ehdr->h_proto == rx->sdata->control_port_protocol &&
1822             (ether_addr_equal(ehdr->h_dest, rx->sdata->vif.addr) ||
1823              ether_addr_equal(ehdr->h_dest, pae_group_addr)))
1824                 return true;
1825
1826         if (ieee80211_802_1x_port_control(rx) ||
1827             ieee80211_drop_unencrypted(rx, fc))
1828                 return false;
1829
1830         return true;
1831 }
1832
1833 /*
1834  * requires that rx->skb is a frame with ethernet header
1835  */
1836 static void
1837 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1838 {
1839         struct ieee80211_sub_if_data *sdata = rx->sdata;
1840         struct net_device *dev = sdata->dev;
1841         struct sk_buff *skb, *xmit_skb;
1842         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1843         struct sta_info *dsta;
1844         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1845
1846         skb = rx->skb;
1847         xmit_skb = NULL;
1848
1849         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1850              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1851             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1852             (status->rx_flags & IEEE80211_RX_RA_MATCH) &&
1853             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1854                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1855                         /*
1856                          * send multicast frames both to higher layers in
1857                          * local net stack and back to the wireless medium
1858                          */
1859                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1860                         if (!xmit_skb)
1861                                 net_info_ratelimited("%s: failed to clone multicast frame\n",
1862                                                     dev->name);
1863                 } else {
1864                         dsta = sta_info_get(sdata, skb->data);
1865                         if (dsta) {
1866                                 /*
1867                                  * The destination station is associated to
1868                                  * this AP (in this VLAN), so send the frame
1869                                  * directly to it and do not pass it to local
1870                                  * net stack.
1871                                  */
1872                                 xmit_skb = skb;
1873                                 skb = NULL;
1874                         }
1875                 }
1876         }
1877
1878         if (skb) {
1879                 int align __maybe_unused;
1880
1881 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1882                 /*
1883                  * 'align' will only take the values 0 or 2 here
1884                  * since all frames are required to be aligned
1885                  * to 2-byte boundaries when being passed to
1886                  * mac80211; the code here works just as well if
1887                  * that isn't true, but mac80211 assumes it can
1888                  * access fields as 2-byte aligned (e.g. for
1889                  * compare_ether_addr)
1890                  */
1891                 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1892                 if (align) {
1893                         if (WARN_ON(skb_headroom(skb) < 3)) {
1894                                 dev_kfree_skb(skb);
1895                                 skb = NULL;
1896                         } else {
1897                                 u8 *data = skb->data;
1898                                 size_t len = skb_headlen(skb);
1899                                 skb->data -= align;
1900                                 memmove(skb->data, data, len);
1901                                 skb_set_tail_pointer(skb, len);
1902                         }
1903                 }
1904 #endif
1905
1906                 if (skb) {
1907                         /* deliver to local stack */
1908                         skb->protocol = eth_type_trans(skb, dev);
1909                         memset(skb->cb, 0, sizeof(skb->cb));
1910                         netif_receive_skb(skb);
1911                 }
1912         }
1913
1914         if (xmit_skb) {
1915                 /*
1916                  * Send to wireless media and increase priority by 256 to
1917                  * keep the received priority instead of reclassifying
1918                  * the frame (see cfg80211_classify8021d).
1919                  */
1920                 xmit_skb->priority += 256;
1921                 xmit_skb->protocol = htons(ETH_P_802_3);
1922                 skb_reset_network_header(xmit_skb);
1923                 skb_reset_mac_header(xmit_skb);
1924                 dev_queue_xmit(xmit_skb);
1925         }
1926 }
1927
1928 static ieee80211_rx_result debug_noinline
1929 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1930 {
1931         struct net_device *dev = rx->sdata->dev;
1932         struct sk_buff *skb = rx->skb;
1933         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1934         __le16 fc = hdr->frame_control;
1935         struct sk_buff_head frame_list;
1936         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1937
1938         if (unlikely(!ieee80211_is_data(fc)))
1939                 return RX_CONTINUE;
1940
1941         if (unlikely(!ieee80211_is_data_present(fc)))
1942                 return RX_DROP_MONITOR;
1943
1944         if (!(status->rx_flags & IEEE80211_RX_AMSDU))
1945                 return RX_CONTINUE;
1946
1947         if (ieee80211_has_a4(hdr->frame_control) &&
1948             rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1949             !rx->sdata->u.vlan.sta)
1950                 return RX_DROP_UNUSABLE;
1951
1952         if (is_multicast_ether_addr(hdr->addr1) &&
1953             ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1954               rx->sdata->u.vlan.sta) ||
1955              (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1956               rx->sdata->u.mgd.use_4addr)))
1957                 return RX_DROP_UNUSABLE;
1958
1959         skb->dev = dev;
1960         __skb_queue_head_init(&frame_list);
1961
1962         if (skb_linearize(skb))
1963                 return RX_DROP_UNUSABLE;
1964
1965         ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1966                                  rx->sdata->vif.type,
1967                                  rx->local->hw.extra_tx_headroom, true);
1968
1969         while (!skb_queue_empty(&frame_list)) {
1970                 rx->skb = __skb_dequeue(&frame_list);
1971
1972                 if (!ieee80211_frame_allowed(rx, fc)) {
1973                         dev_kfree_skb(rx->skb);
1974                         continue;
1975                 }
1976                 dev->stats.rx_packets++;
1977                 dev->stats.rx_bytes += rx->skb->len;
1978
1979                 ieee80211_deliver_skb(rx);
1980         }
1981
1982         return RX_QUEUED;
1983 }
1984
1985 #ifdef CONFIG_MAC80211_MESH
1986 static ieee80211_rx_result
1987 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1988 {
1989         struct ieee80211_hdr *fwd_hdr, *hdr;
1990         struct ieee80211_tx_info *info;
1991         struct ieee80211s_hdr *mesh_hdr;
1992         struct sk_buff *skb = rx->skb, *fwd_skb;
1993         struct ieee80211_local *local = rx->local;
1994         struct ieee80211_sub_if_data *sdata = rx->sdata;
1995         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1996         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
1997         __le16 reason = cpu_to_le16(WLAN_REASON_MESH_PATH_NOFORWARD);
1998         u16 q, hdrlen;
1999
2000         hdr = (struct ieee80211_hdr *) skb->data;
2001         hdrlen = ieee80211_hdrlen(hdr->frame_control);
2002
2003         /* make sure fixed part of mesh header is there, also checks skb len */
2004         if (!pskb_may_pull(rx->skb, hdrlen + 6))
2005                 return RX_DROP_MONITOR;
2006
2007         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2008
2009         /* make sure full mesh header is there, also checks skb len */
2010         if (!pskb_may_pull(rx->skb,
2011                            hdrlen + ieee80211_get_mesh_hdrlen(mesh_hdr)))
2012                 return RX_DROP_MONITOR;
2013
2014         /* reload pointers */
2015         hdr = (struct ieee80211_hdr *) skb->data;
2016         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2017
2018         /* frame is in RMC, don't forward */
2019         if (ieee80211_is_data(hdr->frame_control) &&
2020             is_multicast_ether_addr(hdr->addr1) &&
2021             mesh_rmc_check(rx->sdata, hdr->addr3, mesh_hdr))
2022                 return RX_DROP_MONITOR;
2023
2024         if (!ieee80211_is_data(hdr->frame_control) ||
2025             !(status->rx_flags & IEEE80211_RX_RA_MATCH))
2026                 return RX_CONTINUE;
2027
2028         if (!mesh_hdr->ttl)
2029                 return RX_DROP_MONITOR;
2030
2031         if (mesh_hdr->flags & MESH_FLAGS_AE) {
2032                 struct mesh_path *mppath;
2033                 char *proxied_addr;
2034                 char *mpp_addr;
2035
2036                 if (is_multicast_ether_addr(hdr->addr1)) {
2037                         mpp_addr = hdr->addr3;
2038                         proxied_addr = mesh_hdr->eaddr1;
2039                 } else if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6) {
2040                         /* has_a4 already checked in ieee80211_rx_mesh_check */
2041                         mpp_addr = hdr->addr4;
2042                         proxied_addr = mesh_hdr->eaddr2;
2043                 } else {
2044                         return RX_DROP_MONITOR;
2045                 }
2046
2047                 rcu_read_lock();
2048                 mppath = mpp_path_lookup(sdata, proxied_addr);
2049                 if (!mppath) {
2050                         mpp_path_add(sdata, proxied_addr, mpp_addr);
2051                 } else {
2052                         spin_lock_bh(&mppath->state_lock);
2053                         if (!ether_addr_equal(mppath->mpp, mpp_addr))
2054                                 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
2055                         spin_unlock_bh(&mppath->state_lock);
2056                 }
2057                 rcu_read_unlock();
2058         }
2059
2060         /* Frame has reached destination.  Don't forward */
2061         if (!is_multicast_ether_addr(hdr->addr1) &&
2062             ether_addr_equal(sdata->vif.addr, hdr->addr3))
2063                 return RX_CONTINUE;
2064
2065         q = ieee80211_select_queue_80211(sdata, skb, hdr);
2066         if (ieee80211_queue_stopped(&local->hw, q)) {
2067                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion);
2068                 return RX_DROP_MONITOR;
2069         }
2070         skb_set_queue_mapping(skb, q);
2071
2072         if (!--mesh_hdr->ttl) {
2073                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
2074                 goto out;
2075         }
2076
2077         if (!ifmsh->mshcfg.dot11MeshForwarding)
2078                 goto out;
2079
2080         fwd_skb = skb_copy(skb, GFP_ATOMIC);
2081         if (!fwd_skb) {
2082                 net_info_ratelimited("%s: failed to clone mesh frame\n",
2083                                     sdata->name);
2084                 goto out;
2085         }
2086
2087         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
2088         fwd_hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_RETRY);
2089         info = IEEE80211_SKB_CB(fwd_skb);
2090         memset(info, 0, sizeof(*info));
2091         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
2092         info->control.vif = &rx->sdata->vif;
2093         info->control.jiffies = jiffies;
2094         if (is_multicast_ether_addr(fwd_hdr->addr1)) {
2095                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_mcast);
2096                 memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
2097                 /* update power mode indication when forwarding */
2098                 ieee80211_mps_set_frame_flags(sdata, NULL, fwd_hdr);
2099         } else if (!mesh_nexthop_lookup(sdata, fwd_skb)) {
2100                 /* mesh power mode flags updated in mesh_nexthop_lookup */
2101                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_unicast);
2102         } else {
2103                 /* unable to resolve next hop */
2104                 mesh_path_error_tx(sdata, ifmsh->mshcfg.element_ttl,
2105                                    fwd_hdr->addr3, 0, reason, fwd_hdr->addr2);
2106                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_no_route);
2107                 kfree_skb(fwd_skb);
2108                 return RX_DROP_MONITOR;
2109         }
2110
2111         IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_frames);
2112         ieee80211_add_pending_skb(local, fwd_skb);
2113  out:
2114         if (is_multicast_ether_addr(hdr->addr1) ||
2115             sdata->dev->flags & IFF_PROMISC)
2116                 return RX_CONTINUE;
2117         else
2118                 return RX_DROP_MONITOR;
2119 }
2120 #endif
2121
2122 static ieee80211_rx_result debug_noinline
2123 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
2124 {
2125         struct ieee80211_sub_if_data *sdata = rx->sdata;
2126         struct ieee80211_local *local = rx->local;
2127         struct net_device *dev = sdata->dev;
2128         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2129         __le16 fc = hdr->frame_control;
2130         bool port_control;
2131         int err;
2132
2133         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
2134                 return RX_CONTINUE;
2135
2136         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
2137                 return RX_DROP_MONITOR;
2138
2139         /*
2140          * Send unexpected-4addr-frame event to hostapd. For older versions,
2141          * also drop the frame to cooked monitor interfaces.
2142          */
2143         if (ieee80211_has_a4(hdr->frame_control) &&
2144             sdata->vif.type == NL80211_IFTYPE_AP) {
2145                 if (rx->sta &&
2146                     !test_and_set_sta_flag(rx->sta, WLAN_STA_4ADDR_EVENT))
2147                         cfg80211_rx_unexpected_4addr_frame(
2148                                 rx->sdata->dev, rx->sta->sta.addr, GFP_ATOMIC);
2149                 return RX_DROP_MONITOR;
2150         }
2151
2152         err = __ieee80211_data_to_8023(rx, &port_control);
2153         if (unlikely(err))
2154                 return RX_DROP_UNUSABLE;
2155
2156         if (!ieee80211_frame_allowed(rx, fc))
2157                 return RX_DROP_MONITOR;
2158
2159         if (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
2160             unlikely(port_control) && sdata->bss) {
2161                 sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
2162                                      u.ap);
2163                 dev = sdata->dev;
2164                 rx->sdata = sdata;
2165         }
2166
2167         rx->skb->dev = dev;
2168
2169         dev->stats.rx_packets++;
2170         dev->stats.rx_bytes += rx->skb->len;
2171
2172         if (local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
2173             !is_multicast_ether_addr(
2174                     ((struct ethhdr *)rx->skb->data)->h_dest) &&
2175             (!local->scanning &&
2176              !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state))) {
2177                         mod_timer(&local->dynamic_ps_timer, jiffies +
2178                          msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
2179         }
2180
2181         ieee80211_deliver_skb(rx);
2182
2183         return RX_QUEUED;
2184 }
2185
2186 static ieee80211_rx_result debug_noinline
2187 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
2188 {
2189         struct sk_buff *skb = rx->skb;
2190         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
2191         struct tid_ampdu_rx *tid_agg_rx;
2192         u16 start_seq_num;
2193         u16 tid;
2194
2195         if (likely(!ieee80211_is_ctl(bar->frame_control)))
2196                 return RX_CONTINUE;
2197
2198         if (ieee80211_is_back_req(bar->frame_control)) {
2199                 struct {
2200                         __le16 control, start_seq_num;
2201                 } __packed bar_data;
2202
2203                 if (!rx->sta)
2204                         return RX_DROP_MONITOR;
2205
2206                 if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
2207                                   &bar_data, sizeof(bar_data)))
2208                         return RX_DROP_MONITOR;
2209
2210                 tid = le16_to_cpu(bar_data.control) >> 12;
2211
2212                 tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
2213                 if (!tid_agg_rx)
2214                         return RX_DROP_MONITOR;
2215
2216                 start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
2217
2218                 /* reset session timer */
2219                 if (tid_agg_rx->timeout)
2220                         mod_timer(&tid_agg_rx->session_timer,
2221                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
2222
2223                 spin_lock(&tid_agg_rx->reorder_lock);
2224                 /* release stored frames up to start of BAR */
2225                 ieee80211_release_reorder_frames(rx->sdata, tid_agg_rx,
2226                                                  start_seq_num, frames);
2227                 spin_unlock(&tid_agg_rx->reorder_lock);
2228
2229                 kfree_skb(skb);
2230                 return RX_QUEUED;
2231         }
2232
2233         /*
2234          * After this point, we only want management frames,
2235          * so we can drop all remaining control frames to
2236          * cooked monitor interfaces.
2237          */
2238         return RX_DROP_MONITOR;
2239 }
2240
2241 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
2242                                            struct ieee80211_mgmt *mgmt,
2243                                            size_t len)
2244 {
2245         struct ieee80211_local *local = sdata->local;
2246         struct sk_buff *skb;
2247         struct ieee80211_mgmt *resp;
2248
2249         if (!ether_addr_equal(mgmt->da, sdata->vif.addr)) {
2250                 /* Not to own unicast address */
2251                 return;
2252         }
2253
2254         if (!ether_addr_equal(mgmt->sa, sdata->u.mgd.bssid) ||
2255             !ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid)) {
2256                 /* Not from the current AP or not associated yet. */
2257                 return;
2258         }
2259
2260         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
2261                 /* Too short SA Query request frame */
2262                 return;
2263         }
2264
2265         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
2266         if (skb == NULL)
2267                 return;
2268
2269         skb_reserve(skb, local->hw.extra_tx_headroom);
2270         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
2271         memset(resp, 0, 24);
2272         memcpy(resp->da, mgmt->sa, ETH_ALEN);
2273         memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
2274         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
2275         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2276                                           IEEE80211_STYPE_ACTION);
2277         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
2278         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
2279         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
2280         memcpy(resp->u.action.u.sa_query.trans_id,
2281                mgmt->u.action.u.sa_query.trans_id,
2282                WLAN_SA_QUERY_TR_ID_LEN);
2283
2284         ieee80211_tx_skb(sdata, skb);
2285 }
2286
2287 static ieee80211_rx_result debug_noinline
2288 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
2289 {
2290         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2291         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2292
2293         /*
2294          * From here on, look only at management frames.
2295          * Data and control frames are already handled,
2296          * and unknown (reserved) frames are useless.
2297          */
2298         if (rx->skb->len < 24)
2299                 return RX_DROP_MONITOR;
2300
2301         if (!ieee80211_is_mgmt(mgmt->frame_control))
2302                 return RX_DROP_MONITOR;
2303
2304         if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
2305             ieee80211_is_beacon(mgmt->frame_control) &&
2306             !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) {
2307                 int sig = 0;
2308
2309                 if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2310                         sig = status->signal;
2311
2312                 cfg80211_report_obss_beacon(rx->local->hw.wiphy,
2313                                             rx->skb->data, rx->skb->len,
2314                                             status->freq, sig);
2315                 rx->flags |= IEEE80211_RX_BEACON_REPORTED;
2316         }
2317
2318         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2319                 return RX_DROP_MONITOR;
2320
2321         if (ieee80211_drop_unencrypted_mgmt(rx))
2322                 return RX_DROP_UNUSABLE;
2323
2324         return RX_CONTINUE;
2325 }
2326
2327 static ieee80211_rx_result debug_noinline
2328 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2329 {
2330         struct ieee80211_local *local = rx->local;
2331         struct ieee80211_sub_if_data *sdata = rx->sdata;
2332         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2333         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2334         int len = rx->skb->len;
2335
2336         if (!ieee80211_is_action(mgmt->frame_control))
2337                 return RX_CONTINUE;
2338
2339         /* drop too small frames */
2340         if (len < IEEE80211_MIN_ACTION_SIZE)
2341                 return RX_DROP_UNUSABLE;
2342
2343         if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC &&
2344             mgmt->u.action.category != WLAN_CATEGORY_SELF_PROTECTED)
2345                 return RX_DROP_UNUSABLE;
2346
2347         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2348                 return RX_DROP_UNUSABLE;
2349
2350         switch (mgmt->u.action.category) {
2351         case WLAN_CATEGORY_HT:
2352                 /* reject HT action frames from stations not supporting HT */
2353                 if (!rx->sta->sta.ht_cap.ht_supported)
2354                         goto invalid;
2355
2356                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2357                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2358                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2359                     sdata->vif.type != NL80211_IFTYPE_AP &&
2360                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2361                         break;
2362
2363                 /* verify action & smps_control/chanwidth are present */
2364                 if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2365                         goto invalid;
2366
2367                 switch (mgmt->u.action.u.ht_smps.action) {
2368                 case WLAN_HT_ACTION_SMPS: {
2369                         struct ieee80211_supported_band *sband;
2370                         enum ieee80211_smps_mode smps_mode;
2371
2372                         /* convert to HT capability */
2373                         switch (mgmt->u.action.u.ht_smps.smps_control) {
2374                         case WLAN_HT_SMPS_CONTROL_DISABLED:
2375                                 smps_mode = IEEE80211_SMPS_OFF;
2376                                 break;
2377                         case WLAN_HT_SMPS_CONTROL_STATIC:
2378                                 smps_mode = IEEE80211_SMPS_STATIC;
2379                                 break;
2380                         case WLAN_HT_SMPS_CONTROL_DYNAMIC:
2381                                 smps_mode = IEEE80211_SMPS_DYNAMIC;
2382                                 break;
2383                         default:
2384                                 goto invalid;
2385                         }
2386
2387                         /* if no change do nothing */
2388                         if (rx->sta->sta.smps_mode == smps_mode)
2389                                 goto handled;
2390                         rx->sta->sta.smps_mode = smps_mode;
2391
2392                         sband = rx->local->hw.wiphy->bands[status->band];
2393
2394                         rate_control_rate_update(local, sband, rx->sta,
2395                                                  IEEE80211_RC_SMPS_CHANGED);
2396                         goto handled;
2397                 }
2398                 case WLAN_HT_ACTION_NOTIFY_CHANWIDTH: {
2399                         struct ieee80211_supported_band *sband;
2400                         u8 chanwidth = mgmt->u.action.u.ht_notify_cw.chanwidth;
2401                         enum ieee80211_sta_rx_bandwidth new_bw;
2402
2403                         /* If it doesn't support 40 MHz it can't change ... */
2404                         if (!(rx->sta->sta.ht_cap.cap &
2405                                         IEEE80211_HT_CAP_SUP_WIDTH_20_40))
2406                                 goto handled;
2407
2408                         if (chanwidth == IEEE80211_HT_CHANWIDTH_20MHZ)
2409                                 new_bw = IEEE80211_STA_RX_BW_20;
2410                         else
2411                                 new_bw = ieee80211_sta_cur_vht_bw(rx->sta);
2412
2413                         if (rx->sta->sta.bandwidth == new_bw)
2414                                 goto handled;
2415
2416                         sband = rx->local->hw.wiphy->bands[status->band];
2417
2418                         rate_control_rate_update(local, sband, rx->sta,
2419                                                  IEEE80211_RC_BW_CHANGED);
2420                         goto handled;
2421                 }
2422                 default:
2423                         goto invalid;
2424                 }
2425
2426                 break;
2427         case WLAN_CATEGORY_PUBLIC:
2428                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2429                         goto invalid;
2430                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2431                         break;
2432                 if (!rx->sta)
2433                         break;
2434                 if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
2435                         break;
2436                 if (mgmt->u.action.u.ext_chan_switch.action_code !=
2437                                 WLAN_PUB_ACTION_EXT_CHANSW_ANN)
2438                         break;
2439                 if (len < offsetof(struct ieee80211_mgmt,
2440                                    u.action.u.ext_chan_switch.variable))
2441                         goto invalid;
2442                 goto queue;
2443         case WLAN_CATEGORY_VHT:
2444                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2445                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2446                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2447                     sdata->vif.type != NL80211_IFTYPE_AP &&
2448                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2449                         break;
2450
2451                 /* verify action code is present */
2452                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2453                         goto invalid;
2454
2455                 switch (mgmt->u.action.u.vht_opmode_notif.action_code) {
2456                 case WLAN_VHT_ACTION_OPMODE_NOTIF: {
2457                         u8 opmode;
2458
2459                         /* verify opmode is present */
2460                         if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2461                                 goto invalid;
2462
2463                         opmode = mgmt->u.action.u.vht_opmode_notif.operating_mode;
2464
2465                         ieee80211_vht_handle_opmode(rx->sdata, rx->sta,
2466                                                     opmode, status->band,
2467                                                     false);
2468                         goto handled;
2469                 }
2470                 default:
2471                         break;
2472                 }
2473                 break;
2474         case WLAN_CATEGORY_BACK:
2475                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2476                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2477                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2478                     sdata->vif.type != NL80211_IFTYPE_AP &&
2479                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2480                         break;
2481
2482                 /* verify action_code is present */
2483                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2484                         break;
2485
2486                 switch (mgmt->u.action.u.addba_req.action_code) {
2487                 case WLAN_ACTION_ADDBA_REQ:
2488                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2489                                    sizeof(mgmt->u.action.u.addba_req)))
2490                                 goto invalid;
2491                         break;
2492                 case WLAN_ACTION_ADDBA_RESP:
2493                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2494                                    sizeof(mgmt->u.action.u.addba_resp)))
2495                                 goto invalid;
2496                         break;
2497                 case WLAN_ACTION_DELBA:
2498                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2499                                    sizeof(mgmt->u.action.u.delba)))
2500                                 goto invalid;
2501                         break;
2502                 default:
2503                         goto invalid;
2504                 }
2505
2506                 goto queue;
2507         case WLAN_CATEGORY_SPECTRUM_MGMT:
2508                 if (status->band != IEEE80211_BAND_5GHZ)
2509                         break;
2510
2511                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2512                         break;
2513
2514                 /* verify action_code is present */
2515                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2516                         break;
2517
2518                 switch (mgmt->u.action.u.measurement.action_code) {
2519                 case WLAN_ACTION_SPCT_MSR_REQ:
2520                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2521                                    sizeof(mgmt->u.action.u.measurement)))
2522                                 break;
2523                         ieee80211_process_measurement_req(sdata, mgmt, len);
2524                         goto handled;
2525                 case WLAN_ACTION_SPCT_CHL_SWITCH:
2526                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2527                                 break;
2528
2529                         if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
2530                                 break;
2531
2532                         goto queue;
2533                 }
2534                 break;
2535         case WLAN_CATEGORY_SA_QUERY:
2536                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2537                            sizeof(mgmt->u.action.u.sa_query)))
2538                         break;
2539
2540                 switch (mgmt->u.action.u.sa_query.action) {
2541                 case WLAN_ACTION_SA_QUERY_REQUEST:
2542                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2543                                 break;
2544                         ieee80211_process_sa_query_req(sdata, mgmt, len);
2545                         goto handled;
2546                 }
2547                 break;
2548         case WLAN_CATEGORY_SELF_PROTECTED:
2549                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2550                            sizeof(mgmt->u.action.u.self_prot.action_code)))
2551                         break;
2552
2553                 switch (mgmt->u.action.u.self_prot.action_code) {
2554                 case WLAN_SP_MESH_PEERING_OPEN:
2555                 case WLAN_SP_MESH_PEERING_CLOSE:
2556                 case WLAN_SP_MESH_PEERING_CONFIRM:
2557                         if (!ieee80211_vif_is_mesh(&sdata->vif))
2558                                 goto invalid;
2559                         if (sdata->u.mesh.user_mpm)
2560                                 /* userspace handles this frame */
2561                                 break;
2562                         goto queue;
2563                 case WLAN_SP_MGK_INFORM:
2564                 case WLAN_SP_MGK_ACK:
2565                         if (!ieee80211_vif_is_mesh(&sdata->vif))
2566                                 goto invalid;
2567                         break;
2568                 }
2569                 break;
2570         case WLAN_CATEGORY_MESH_ACTION:
2571                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2572                            sizeof(mgmt->u.action.u.mesh_action.action_code)))
2573                         break;
2574
2575                 if (!ieee80211_vif_is_mesh(&sdata->vif))
2576                         break;
2577                 if (mesh_action_is_path_sel(mgmt) &&
2578                     !mesh_path_sel_is_hwmp(sdata))
2579                         break;
2580                 goto queue;
2581         }
2582
2583         return RX_CONTINUE;
2584
2585  invalid:
2586         status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
2587         /* will return in the next handlers */
2588         return RX_CONTINUE;
2589
2590  handled:
2591         if (rx->sta)
2592                 rx->sta->rx_packets++;
2593         dev_kfree_skb(rx->skb);
2594         return RX_QUEUED;
2595
2596  queue:
2597         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2598         skb_queue_tail(&sdata->skb_queue, rx->skb);
2599         ieee80211_queue_work(&local->hw, &sdata->work);
2600         if (rx->sta)
2601                 rx->sta->rx_packets++;
2602         return RX_QUEUED;
2603 }
2604
2605 static ieee80211_rx_result debug_noinline
2606 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
2607 {
2608         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2609         int sig = 0;
2610
2611         /* skip known-bad action frames and return them in the next handler */
2612         if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
2613                 return RX_CONTINUE;
2614
2615         /*
2616          * Getting here means the kernel doesn't know how to handle
2617          * it, but maybe userspace does ... include returned frames
2618          * so userspace can register for those to know whether ones
2619          * it transmitted were processed or returned.
2620          */
2621
2622         if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2623                 sig = status->signal;
2624
2625         if (cfg80211_rx_mgmt(&rx->sdata->wdev, status->freq, sig,
2626                              rx->skb->data, rx->skb->len,
2627                              GFP_ATOMIC)) {
2628                 if (rx->sta)
2629                         rx->sta->rx_packets++;
2630                 dev_kfree_skb(rx->skb);
2631                 return RX_QUEUED;
2632         }
2633
2634         return RX_CONTINUE;
2635 }
2636
2637 static ieee80211_rx_result debug_noinline
2638 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
2639 {
2640         struct ieee80211_local *local = rx->local;
2641         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2642         struct sk_buff *nskb;
2643         struct ieee80211_sub_if_data *sdata = rx->sdata;
2644         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2645
2646         if (!ieee80211_is_action(mgmt->frame_control))
2647                 return RX_CONTINUE;
2648
2649         /*
2650          * For AP mode, hostapd is responsible for handling any action
2651          * frames that we didn't handle, including returning unknown
2652          * ones. For all other modes we will return them to the sender,
2653          * setting the 0x80 bit in the action category, as required by
2654          * 802.11-2012 9.24.4.
2655          * Newer versions of hostapd shall also use the management frame
2656          * registration mechanisms, but older ones still use cooked
2657          * monitor interfaces so push all frames there.
2658          */
2659         if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
2660             (sdata->vif.type == NL80211_IFTYPE_AP ||
2661              sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
2662                 return RX_DROP_MONITOR;
2663
2664         if (is_multicast_ether_addr(mgmt->da))
2665                 return RX_DROP_MONITOR;
2666
2667         /* do not return rejected action frames */
2668         if (mgmt->u.action.category & 0x80)
2669                 return RX_DROP_UNUSABLE;
2670
2671         nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2672                                GFP_ATOMIC);
2673         if (nskb) {
2674                 struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
2675
2676                 nmgmt->u.action.category |= 0x80;
2677                 memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
2678                 memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2679
2680                 memset(nskb->cb, 0, sizeof(nskb->cb));
2681
2682                 if (rx->sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE) {
2683                         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(nskb);
2684
2685                         info->flags = IEEE80211_TX_CTL_TX_OFFCHAN |
2686                                       IEEE80211_TX_INTFL_OFFCHAN_TX_OK |
2687                                       IEEE80211_TX_CTL_NO_CCK_RATE;
2688                         if (local->hw.flags & IEEE80211_HW_QUEUE_CONTROL)
2689                                 info->hw_queue =
2690                                         local->hw.offchannel_tx_hw_queue;
2691                 }
2692
2693                 __ieee80211_tx_skb_tid_band(rx->sdata, nskb, 7,
2694                                             status->band);
2695         }
2696         dev_kfree_skb(rx->skb);
2697         return RX_QUEUED;
2698 }
2699
2700 static ieee80211_rx_result debug_noinline
2701 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2702 {
2703         struct ieee80211_sub_if_data *sdata = rx->sdata;
2704         struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2705         __le16 stype;
2706
2707         stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2708
2709         if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2710             sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2711             sdata->vif.type != NL80211_IFTYPE_STATION)
2712                 return RX_DROP_MONITOR;
2713
2714         switch (stype) {
2715         case cpu_to_le16(IEEE80211_STYPE_AUTH):
2716         case cpu_to_le16(IEEE80211_STYPE_BEACON):
2717         case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2718                 /* process for all: mesh, mlme, ibss */
2719                 break;
2720         case cpu_to_le16(IEEE80211_STYPE_ASSOC_RESP):
2721         case cpu_to_le16(IEEE80211_STYPE_REASSOC_RESP):
2722         case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2723         case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2724                 if (is_multicast_ether_addr(mgmt->da) &&
2725                     !is_broadcast_ether_addr(mgmt->da))
2726                         return RX_DROP_MONITOR;
2727
2728                 /* process only for station */
2729                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2730                         return RX_DROP_MONITOR;
2731                 break;
2732         case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2733                 /* process only for ibss and mesh */
2734                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2735                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT)
2736                         return RX_DROP_MONITOR;
2737                 break;
2738         default:
2739                 return RX_DROP_MONITOR;
2740         }
2741
2742         /* queue up frame and kick off work to process it */
2743         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2744         skb_queue_tail(&sdata->skb_queue, rx->skb);
2745         ieee80211_queue_work(&rx->local->hw, &sdata->work);
2746         if (rx->sta)
2747                 rx->sta->rx_packets++;
2748
2749         return RX_QUEUED;
2750 }
2751
2752 /* TODO: use IEEE80211_RX_FRAGMENTED */
2753 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2754                                         struct ieee80211_rate *rate)
2755 {
2756         struct ieee80211_sub_if_data *sdata;
2757         struct ieee80211_local *local = rx->local;
2758         struct sk_buff *skb = rx->skb, *skb2;
2759         struct net_device *prev_dev = NULL;
2760         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2761         int needed_headroom;
2762
2763         /*
2764          * If cooked monitor has been processed already, then
2765          * don't do it again. If not, set the flag.
2766          */
2767         if (rx->flags & IEEE80211_RX_CMNTR)
2768                 goto out_free_skb;
2769         rx->flags |= IEEE80211_RX_CMNTR;
2770
2771         /* If there are no cooked monitor interfaces, just free the SKB */
2772         if (!local->cooked_mntrs)
2773                 goto out_free_skb;
2774
2775         /* room for the radiotap header based on driver features */
2776         needed_headroom = ieee80211_rx_radiotap_space(local, status);
2777
2778         if (skb_headroom(skb) < needed_headroom &&
2779             pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC))
2780                 goto out_free_skb;
2781
2782         /* prepend radiotap information */
2783         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
2784                                          false);
2785
2786         skb_set_mac_header(skb, 0);
2787         skb->ip_summed = CHECKSUM_UNNECESSARY;
2788         skb->pkt_type = PACKET_OTHERHOST;
2789         skb->protocol = htons(ETH_P_802_2);
2790
2791         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2792                 if (!ieee80211_sdata_running(sdata))
2793                         continue;
2794
2795                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2796                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2797                         continue;
2798
2799                 if (prev_dev) {
2800                         skb2 = skb_clone(skb, GFP_ATOMIC);
2801                         if (skb2) {
2802                                 skb2->dev = prev_dev;
2803                                 netif_receive_skb(skb2);
2804                         }
2805                 }
2806
2807                 prev_dev = sdata->dev;
2808                 sdata->dev->stats.rx_packets++;
2809                 sdata->dev->stats.rx_bytes += skb->len;
2810         }
2811
2812         if (prev_dev) {
2813                 skb->dev = prev_dev;
2814                 netif_receive_skb(skb);
2815                 return;
2816         }
2817
2818  out_free_skb:
2819         dev_kfree_skb(skb);
2820 }
2821
2822 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
2823                                          ieee80211_rx_result res)
2824 {
2825         switch (res) {
2826         case RX_DROP_MONITOR:
2827                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2828                 if (rx->sta)
2829                         rx->sta->rx_dropped++;
2830                 /* fall through */
2831         case RX_CONTINUE: {
2832                 struct ieee80211_rate *rate = NULL;
2833                 struct ieee80211_supported_band *sband;
2834                 struct ieee80211_rx_status *status;
2835
2836                 status = IEEE80211_SKB_RXCB((rx->skb));
2837
2838                 sband = rx->local->hw.wiphy->bands[status->band];
2839                 if (!(status->flag & RX_FLAG_HT) &&
2840                     !(status->flag & RX_FLAG_VHT))
2841                         rate = &sband->bitrates[status->rate_idx];
2842
2843                 ieee80211_rx_cooked_monitor(rx, rate);
2844                 break;
2845                 }
2846         case RX_DROP_UNUSABLE:
2847                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2848                 if (rx->sta)
2849                         rx->sta->rx_dropped++;
2850                 dev_kfree_skb(rx->skb);
2851                 break;
2852         case RX_QUEUED:
2853                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
2854                 break;
2855         }
2856 }
2857
2858 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
2859                                   struct sk_buff_head *frames)
2860 {
2861         ieee80211_rx_result res = RX_DROP_MONITOR;
2862         struct sk_buff *skb;
2863
2864 #define CALL_RXH(rxh)                   \
2865         do {                            \
2866                 res = rxh(rx);          \
2867                 if (res != RX_CONTINUE) \
2868                         goto rxh_next;  \
2869         } while (0);
2870
2871         spin_lock_bh(&rx->local->rx_path_lock);
2872
2873         while ((skb = __skb_dequeue(frames))) {
2874                 /*
2875                  * all the other fields are valid across frames
2876                  * that belong to an aMPDU since they are on the
2877                  * same TID from the same station
2878                  */
2879                 rx->skb = skb;
2880
2881                 CALL_RXH(ieee80211_rx_h_decrypt)
2882                 CALL_RXH(ieee80211_rx_h_check_more_data)
2883                 CALL_RXH(ieee80211_rx_h_uapsd_and_pspoll)
2884                 CALL_RXH(ieee80211_rx_h_sta_process)
2885                 CALL_RXH(ieee80211_rx_h_defragment)
2886                 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2887                 /* must be after MMIC verify so header is counted in MPDU mic */
2888 #ifdef CONFIG_MAC80211_MESH
2889                 if (ieee80211_vif_is_mesh(&rx->sdata->vif))
2890                         CALL_RXH(ieee80211_rx_h_mesh_fwding);
2891 #endif
2892                 CALL_RXH(ieee80211_rx_h_amsdu)
2893                 CALL_RXH(ieee80211_rx_h_data)
2894
2895                 /* special treatment -- needs the queue */
2896                 res = ieee80211_rx_h_ctrl(rx, frames);
2897                 if (res != RX_CONTINUE)
2898                         goto rxh_next;
2899
2900                 CALL_RXH(ieee80211_rx_h_mgmt_check)
2901                 CALL_RXH(ieee80211_rx_h_action)
2902                 CALL_RXH(ieee80211_rx_h_userspace_mgmt)
2903                 CALL_RXH(ieee80211_rx_h_action_return)
2904                 CALL_RXH(ieee80211_rx_h_mgmt)
2905
2906  rxh_next:
2907                 ieee80211_rx_handlers_result(rx, res);
2908
2909 #undef CALL_RXH
2910         }
2911
2912         spin_unlock_bh(&rx->local->rx_path_lock);
2913 }
2914
2915 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
2916 {
2917         struct sk_buff_head reorder_release;
2918         ieee80211_rx_result res = RX_DROP_MONITOR;
2919
2920         __skb_queue_head_init(&reorder_release);
2921
2922 #define CALL_RXH(rxh)                   \
2923         do {                            \
2924                 res = rxh(rx);          \
2925                 if (res != RX_CONTINUE) \
2926                         goto rxh_next;  \
2927         } while (0);
2928
2929         CALL_RXH(ieee80211_rx_h_check)
2930
2931         ieee80211_rx_reorder_ampdu(rx, &reorder_release);
2932
2933         ieee80211_rx_handlers(rx, &reorder_release);
2934         return;
2935
2936  rxh_next:
2937         ieee80211_rx_handlers_result(rx, res);
2938
2939 #undef CALL_RXH
2940 }
2941
2942 /*
2943  * This function makes calls into the RX path, therefore
2944  * it has to be invoked under RCU read lock.
2945  */
2946 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
2947 {
2948         struct sk_buff_head frames;
2949         struct ieee80211_rx_data rx = {
2950                 .sta = sta,
2951                 .sdata = sta->sdata,
2952                 .local = sta->local,
2953                 /* This is OK -- must be QoS data frame */
2954                 .security_idx = tid,
2955                 .seqno_idx = tid,
2956                 .flags = 0,
2957         };
2958         struct tid_ampdu_rx *tid_agg_rx;
2959
2960         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
2961         if (!tid_agg_rx)
2962                 return;
2963
2964         __skb_queue_head_init(&frames);
2965
2966         spin_lock(&tid_agg_rx->reorder_lock);
2967         ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx, &frames);
2968         spin_unlock(&tid_agg_rx->reorder_lock);
2969
2970         ieee80211_rx_handlers(&rx, &frames);
2971 }
2972
2973 /* main receive path */
2974
2975 static int prepare_for_handlers(struct ieee80211_rx_data *rx,
2976                                 struct ieee80211_hdr *hdr)
2977 {
2978         struct ieee80211_sub_if_data *sdata = rx->sdata;
2979         struct sk_buff *skb = rx->skb;
2980         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2981         u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2982         int multicast = is_multicast_ether_addr(hdr->addr1);
2983
2984         switch (sdata->vif.type) {
2985         case NL80211_IFTYPE_STATION:
2986                 if (!bssid && !sdata->u.mgd.use_4addr)
2987                         return 0;
2988                 if (!multicast &&
2989                     !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
2990                         if (!(sdata->dev->flags & IFF_PROMISC) ||
2991                             sdata->u.mgd.use_4addr)
2992                                 return 0;
2993                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
2994                 }
2995                 break;
2996         case NL80211_IFTYPE_ADHOC:
2997                 if (!bssid)
2998                         return 0;
2999                 if (ieee80211_is_beacon(hdr->frame_control)) {
3000                         return 1;
3001                 } else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
3002                         return 0;
3003                 } else if (!multicast &&
3004                            !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
3005                         if (!(sdata->dev->flags & IFF_PROMISC))
3006                                 return 0;
3007                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3008                 } else if (!rx->sta) {
3009                         int rate_idx;
3010                         if (status->flag & (RX_FLAG_HT | RX_FLAG_VHT))
3011                                 rate_idx = 0; /* TODO: HT/VHT rates */
3012                         else
3013                                 rate_idx = status->rate_idx;
3014                         ieee80211_ibss_rx_no_sta(sdata, bssid, hdr->addr2,
3015                                                  BIT(rate_idx));
3016                 }
3017                 break;
3018         case NL80211_IFTYPE_MESH_POINT:
3019                 if (!multicast &&
3020                     !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
3021                         if (!(sdata->dev->flags & IFF_PROMISC))
3022                                 return 0;
3023
3024                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3025                 }
3026                 break;
3027         case NL80211_IFTYPE_AP_VLAN:
3028         case NL80211_IFTYPE_AP:
3029                 if (!bssid) {
3030                         if (!ether_addr_equal(sdata->vif.addr, hdr->addr1))
3031                                 return 0;
3032                 } else if (!ieee80211_bssid_match(bssid, sdata->vif.addr)) {
3033                         /*
3034                          * Accept public action frames even when the
3035                          * BSSID doesn't match, this is used for P2P
3036                          * and location updates. Note that mac80211
3037                          * itself never looks at these frames.
3038                          */
3039                         if (!multicast &&
3040                             !ether_addr_equal(sdata->vif.addr, hdr->addr1))
3041                                 return 0;
3042                         if (ieee80211_is_public_action(hdr, skb->len))
3043                                 return 1;
3044                         if (!ieee80211_is_beacon(hdr->frame_control))
3045                                 return 0;
3046                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3047                 }
3048                 break;
3049         case NL80211_IFTYPE_WDS:
3050                 if (bssid || !ieee80211_is_data(hdr->frame_control))
3051                         return 0;
3052                 if (!ether_addr_equal(sdata->u.wds.remote_addr, hdr->addr2))
3053                         return 0;
3054                 break;
3055         case NL80211_IFTYPE_P2P_DEVICE:
3056                 if (!ieee80211_is_public_action(hdr, skb->len) &&
3057                     !ieee80211_is_probe_req(hdr->frame_control) &&
3058                     !ieee80211_is_probe_resp(hdr->frame_control) &&
3059                     !ieee80211_is_beacon(hdr->frame_control))
3060                         return 0;
3061                 if (!ether_addr_equal(sdata->vif.addr, hdr->addr1) &&
3062                     !multicast)
3063                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3064                 break;
3065         default:
3066                 /* should never get here */
3067                 WARN_ON_ONCE(1);
3068                 break;
3069         }
3070
3071         return 1;
3072 }
3073
3074 /*
3075  * This function returns whether or not the SKB
3076  * was destined for RX processing or not, which,
3077  * if consume is true, is equivalent to whether
3078  * or not the skb was consumed.
3079  */
3080 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
3081                                             struct sk_buff *skb, bool consume)
3082 {
3083         struct ieee80211_local *local = rx->local;
3084         struct ieee80211_sub_if_data *sdata = rx->sdata;
3085         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3086         struct ieee80211_hdr *hdr = (void *)skb->data;
3087         int prepares;
3088
3089         rx->skb = skb;
3090         status->rx_flags |= IEEE80211_RX_RA_MATCH;
3091         prepares = prepare_for_handlers(rx, hdr);
3092
3093         if (!prepares)
3094                 return false;
3095
3096         if (!consume) {
3097                 skb = skb_copy(skb, GFP_ATOMIC);
3098                 if (!skb) {
3099                         if (net_ratelimit())
3100                                 wiphy_debug(local->hw.wiphy,
3101                                         "failed to copy skb for %s\n",
3102                                         sdata->name);
3103                         return true;
3104                 }
3105
3106                 rx->skb = skb;
3107         }
3108
3109         ieee80211_invoke_rx_handlers(rx);
3110         return true;
3111 }
3112
3113 /*
3114  * This is the actual Rx frames handler. as it blongs to Rx path it must
3115  * be called with rcu_read_lock protection.
3116  */
3117 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
3118                                          struct sk_buff *skb)
3119 {
3120         struct ieee80211_local *local = hw_to_local(hw);
3121         struct ieee80211_sub_if_data *sdata;
3122         struct ieee80211_hdr *hdr;
3123         __le16 fc;
3124         struct ieee80211_rx_data rx;
3125         struct ieee80211_sub_if_data *prev;
3126         struct sta_info *sta, *tmp, *prev_sta;
3127         int err = 0;
3128
3129         fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
3130         memset(&rx, 0, sizeof(rx));
3131         rx.skb = skb;
3132         rx.local = local;
3133
3134         if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
3135                 local->dot11ReceivedFragmentCount++;
3136
3137         if (ieee80211_is_mgmt(fc)) {
3138                 /* drop frame if too short for header */
3139                 if (skb->len < ieee80211_hdrlen(fc))
3140                         err = -ENOBUFS;
3141                 else
3142                         err = skb_linearize(skb);
3143         } else {
3144                 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
3145         }
3146
3147         if (err) {
3148                 dev_kfree_skb(skb);
3149                 return;
3150         }
3151
3152         hdr = (struct ieee80211_hdr *)skb->data;
3153         ieee80211_parse_qos(&rx);
3154         ieee80211_verify_alignment(&rx);
3155
3156         if (unlikely(ieee80211_is_probe_resp(hdr->frame_control) ||
3157                      ieee80211_is_beacon(hdr->frame_control)))
3158                 ieee80211_scan_rx(local, skb);
3159
3160         if (ieee80211_is_data(fc)) {
3161                 prev_sta = NULL;
3162
3163                 for_each_sta_info(local, hdr->addr2, sta, tmp) {
3164                         if (!prev_sta) {
3165                                 prev_sta = sta;
3166                                 continue;
3167                         }
3168
3169                         rx.sta = prev_sta;
3170                         rx.sdata = prev_sta->sdata;
3171                         ieee80211_prepare_and_rx_handle(&rx, skb, false);
3172
3173                         prev_sta = sta;
3174                 }
3175
3176                 if (prev_sta) {
3177                         rx.sta = prev_sta;
3178                         rx.sdata = prev_sta->sdata;
3179
3180                         if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
3181                                 return;
3182                         goto out;
3183                 }
3184         }
3185
3186         prev = NULL;
3187
3188         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
3189                 if (!ieee80211_sdata_running(sdata))
3190                         continue;
3191
3192                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
3193                     sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
3194                         continue;
3195
3196                 /*
3197                  * frame is destined for this interface, but if it's
3198                  * not also for the previous one we handle that after
3199                  * the loop to avoid copying the SKB once too much
3200                  */
3201
3202                 if (!prev) {
3203                         prev = sdata;
3204                         continue;
3205                 }
3206
3207                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
3208                 rx.sdata = prev;
3209                 ieee80211_prepare_and_rx_handle(&rx, skb, false);
3210
3211                 prev = sdata;
3212         }
3213
3214         if (prev) {
3215                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
3216                 rx.sdata = prev;
3217
3218                 if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
3219                         return;
3220         }
3221
3222  out:
3223         dev_kfree_skb(skb);
3224 }
3225
3226 /*
3227  * This is the receive path handler. It is called by a low level driver when an
3228  * 802.11 MPDU is received from the hardware.
3229  */
3230 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
3231 {
3232         struct ieee80211_local *local = hw_to_local(hw);
3233         struct ieee80211_rate *rate = NULL;
3234         struct ieee80211_supported_band *sband;
3235         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3236
3237         WARN_ON_ONCE(softirq_count() == 0);
3238
3239         if (WARN_ON(status->band >= IEEE80211_NUM_BANDS))
3240                 goto drop;
3241
3242         sband = local->hw.wiphy->bands[status->band];
3243         if (WARN_ON(!sband))
3244                 goto drop;
3245
3246         /*
3247          * If we're suspending, it is possible although not too likely
3248          * that we'd be receiving frames after having already partially
3249          * quiesced the stack. We can't process such frames then since
3250          * that might, for example, cause stations to be added or other
3251          * driver callbacks be invoked.
3252          */
3253         if (unlikely(local->quiescing || local->suspended))
3254                 goto drop;
3255
3256         /* We might be during a HW reconfig, prevent Rx for the same reason */
3257         if (unlikely(local->in_reconfig))
3258                 goto drop;
3259
3260         /*
3261          * The same happens when we're not even started,
3262          * but that's worth a warning.
3263          */
3264         if (WARN_ON(!local->started))
3265                 goto drop;
3266
3267         if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
3268                 /*
3269                  * Validate the rate, unless a PLCP error means that
3270                  * we probably can't have a valid rate here anyway.
3271                  */
3272
3273                 if (status->flag & RX_FLAG_HT) {
3274                         /*
3275                          * rate_idx is MCS index, which can be [0-76]
3276                          * as documented on:
3277                          *
3278                          * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
3279                          *
3280                          * Anything else would be some sort of driver or
3281                          * hardware error. The driver should catch hardware
3282                          * errors.
3283                          */
3284                         if (WARN(status->rate_idx > 76,
3285                                  "Rate marked as an HT rate but passed "
3286                                  "status->rate_idx is not "
3287                                  "an MCS index [0-76]: %d (0x%02x)\n",
3288                                  status->rate_idx,
3289                                  status->rate_idx))
3290                                 goto drop;
3291                 } else if (status->flag & RX_FLAG_VHT) {
3292                         if (WARN_ONCE(status->rate_idx > 9 ||
3293                                       !status->vht_nss ||
3294                                       status->vht_nss > 8,
3295                                       "Rate marked as a VHT rate but data is invalid: MCS: %d, NSS: %d\n",
3296                                       status->rate_idx, status->vht_nss))
3297                                 goto drop;
3298                 } else {
3299                         if (WARN_ON(status->rate_idx >= sband->n_bitrates))
3300                                 goto drop;
3301                         rate = &sband->bitrates[status->rate_idx];
3302                 }
3303         }
3304
3305         status->rx_flags = 0;
3306
3307         /*
3308          * key references and virtual interfaces are protected using RCU
3309          * and this requires that we are in a read-side RCU section during
3310          * receive processing
3311          */
3312         rcu_read_lock();
3313
3314         /*
3315          * Frames with failed FCS/PLCP checksum are not returned,
3316          * all other frames are returned without radiotap header
3317          * if it was previously present.
3318          * Also, frames with less than 16 bytes are dropped.
3319          */
3320         skb = ieee80211_rx_monitor(local, skb, rate);
3321         if (!skb) {
3322                 rcu_read_unlock();
3323                 return;
3324         }
3325
3326         ieee80211_tpt_led_trig_rx(local,
3327                         ((struct ieee80211_hdr *)skb->data)->frame_control,
3328                         skb->len);
3329         __ieee80211_rx_handle_packet(hw, skb);
3330
3331         rcu_read_unlock();
3332
3333         return;
3334  drop:
3335         kfree_skb(skb);
3336 }
3337 EXPORT_SYMBOL(ieee80211_rx);
3338
3339 /* This is a version of the rx handler that can be called from hard irq
3340  * context. Post the skb on the queue and schedule the tasklet */
3341 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
3342 {
3343         struct ieee80211_local *local = hw_to_local(hw);
3344
3345         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
3346
3347         skb->pkt_type = IEEE80211_RX_MSG;
3348         skb_queue_tail(&local->skb_queue, skb);
3349         tasklet_schedule(&local->tasklet);
3350 }
3351 EXPORT_SYMBOL(ieee80211_rx_irqsafe);