net/mac80211/rx.c

   1 /*
   2  * Copyright 2002-2005, Instant802 Networks, Inc.
   3  * Copyright 2005-2006, Devicescape Software, Inc.
   4  * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
   5  * Copyright 2007-2010  Johannes Berg <johannes@sipsolutions.net>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/jiffies.h>
  13 #include <linux/slab.h>
  14 #include <linux/kernel.h>
  15 #include <linux/skbuff.h>
  16 #include <linux/netdevice.h>
  17 #include <linux/etherdevice.h>
  18 #include <linux/rcupdate.h>
  19 #include <linux/export.h>
  20 #include <net/mac80211.h>
  21 #include <net/ieee80211_radiotap.h>
  22 #include <asm/unaligned.h>
  23
  24 #include "ieee80211_i.h"
  25 #include "driver-ops.h"
  26 #include "led.h"
  27 #include "mesh.h"
  28 #include "wep.h"
  29 #include "wpa.h"
  30 #include "tkip.h"
  31 #include "wme.h"
  32 #include "rate.h"
  33
  34 /*
  35  * monitor mode reception
  36  *
  37  * This function cleans up the SKB, i.e. it removes all the stuff
  38  * only useful for monitoring.
  39  */
  40 static struct sk_buff *remove_monitor_info(struct ieee80211_local *local,
  41                                            struct sk_buff *skb)
  42 {
  43         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  44
  45         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) {
  46                 if (likely(skb->len > FCS_LEN))
  47                         __pskb_trim(skb, skb->len - FCS_LEN);
  48                 else {
  49                         /* driver bug */
  50                         WARN_ON(1);
  51                         dev_kfree_skb(skb);
  52                         return NULL;
  53                 }
  54         }
  55
  56         if (status->vendor_radiotap_len)
  57                 __pskb_pull(skb, status->vendor_radiotap_len);
  58
  59         return skb;
  60 }
  61
  62 static inline int should_drop_frame(struct sk_buff *skb, int present_fcs_len)
  63 {
  64         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  65         struct ieee80211_hdr *hdr;
  66
  67         hdr = (void *)(skb->data + status->vendor_radiotap_len);
  68
  69         if (status->flag & (RX_FLAG_FAILED_FCS_CRC |
  70                             RX_FLAG_FAILED_PLCP_CRC |
  71                             RX_FLAG_AMPDU_IS_ZEROLEN))
  72                 return 1;
  73         if (unlikely(skb->len < 16 + present_fcs_len +
  74                                 status->vendor_radiotap_len))
  75                 return 1;
  76         if (ieee80211_is_ctl(hdr->frame_control) &&
  77             !ieee80211_is_pspoll(hdr->frame_control) &&
  78             !ieee80211_is_back_req(hdr->frame_control))
  79                 return 1;
  80         return 0;
  81 }
  82
  83 static int
  84 ieee80211_rx_radiotap_space(struct ieee80211_local *local,
  85                             struct ieee80211_rx_status *status)
  86 {
  87         int len;
  88
  89         /* always present fields */
  90         len = sizeof(struct ieee80211_radiotap_header) + 9;
  91
  92         /* allocate extra bitmap */
  93         if (status->vendor_radiotap_len)
  94                 len += 4;
  95
  96         if (ieee80211_have_rx_timestamp(status)) {
  97                 len = ALIGN(len, 8);
  98                 len += 8;
  99         }
 100         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
 101                 len += 1;
 102
 103         /* padding for RX_FLAGS if necessary */
 104         len = ALIGN(len, 2);
 105
 106         if (status->flag & RX_FLAG_HT) /* HT info */
 107                 len += 3;
 108
 109         if (status->flag & RX_FLAG_AMPDU_DETAILS) {
 110                 len = ALIGN(len, 4);
 111                 len += 8;
 112         }
 113
 114         if (status->flag & RX_FLAG_VHT) {
 115                 len = ALIGN(len, 2);
 116                 len += 12;
 117         }
 118
 119         if (status->vendor_radiotap_len) {
 120                 if (WARN_ON_ONCE(status->vendor_radiotap_align == 0))
 121                         status->vendor_radiotap_align = 1;
 122                 /* align standard part of vendor namespace */
 123                 len = ALIGN(len, 2);
 124                 /* allocate standard part of vendor namespace */
 125                 len += 6;
 126                 /* align vendor-defined part */
 127                 len = ALIGN(len, status->vendor_radiotap_align);
 128                 /* vendor-defined part is already in skb */
 129         }
 130
 131         return len;
 132 }
 133
 134 /*
 135  * ieee80211_add_rx_radiotap_header - add radiotap header
 136  *
 137  * add a radiotap header containing all the fields which the hardware provided.
 138  */
 139 static void
 140 ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
 141                                  struct sk_buff *skb,
 142                                  struct ieee80211_rate *rate,
 143                                  int rtap_len, bool has_fcs)
 144 {
 145         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 146         struct ieee80211_radiotap_header *rthdr;
 147         unsigned char *pos;
 148         u16 rx_flags = 0;
 149         int mpdulen;
 150
 151         mpdulen = skb->len;
 152         if (!(has_fcs && (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)))
 153                 mpdulen += FCS_LEN;
 154
 155         rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len);
 156         memset(rthdr, 0, rtap_len);
 157
 158         /* radiotap header, set always present flags */
 159         rthdr->it_present =
 160                 cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
 161                             (1 << IEEE80211_RADIOTAP_CHANNEL) |
 162                             (1 << IEEE80211_RADIOTAP_ANTENNA) |
 163                             (1 << IEEE80211_RADIOTAP_RX_FLAGS));
 164         rthdr->it_len = cpu_to_le16(rtap_len + status->vendor_radiotap_len);
 165
 166         pos = (unsigned char *)(rthdr + 1);
 167
 168         if (status->vendor_radiotap_len) {
 169                 rthdr->it_present |=
 170                         cpu_to_le32(BIT(IEEE80211_RADIOTAP_VENDOR_NAMESPACE)) |
 171                         cpu_to_le32(BIT(IEEE80211_RADIOTAP_EXT));
 172                 put_unaligned_le32(status->vendor_radiotap_bitmap, pos);
 173                 pos += 4;
 174         }
 175
 176         /* the order of the following fields is important */
 177
 178         /* IEEE80211_RADIOTAP_TSFT */
 179         if (ieee80211_have_rx_timestamp(status)) {
 180                 /* padding */
 181                 while ((pos - (u8 *)rthdr) & 7)
 182                         *pos++ = 0;
 183                 put_unaligned_le64(
 184                         ieee80211_calculate_rx_timestamp(local, status,
 185                                                          mpdulen, 0),
 186                         pos);
 187                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT);
 188                 pos += 8;
 189         }
 190
 191         /* IEEE80211_RADIOTAP_FLAGS */
 192         if (has_fcs && (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS))
 193                 *pos |= IEEE80211_RADIOTAP_F_FCS;
 194         if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC))
 195                 *pos |= IEEE80211_RADIOTAP_F_BADFCS;
 196         if (status->flag & RX_FLAG_SHORTPRE)
 197                 *pos |= IEEE80211_RADIOTAP_F_SHORTPRE;
 198         pos++;
 199
 200         /* IEEE80211_RADIOTAP_RATE */
 201         if (!rate || status->flag & (RX_FLAG_HT | RX_FLAG_VHT)) {
 202                 /*
 203                  * Without rate information don't add it. If we have,
 204                  * MCS information is a separate field in radiotap,
 205                  * added below. The byte here is needed as padding
 206                  * for the channel though, so initialise it to 0.
 207                  */
 208                 *pos = 0;
 209         } else {
 210                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
 211                 *pos = rate->bitrate / 5;
 212         }
 213         pos++;
 214
 215         /* IEEE80211_RADIOTAP_CHANNEL */
 216         put_unaligned_le16(status->freq, pos);
 217         pos += 2;
 218         if (status->band == IEEE80211_BAND_5GHZ)
 219                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
 220                                    pos);
 221         else if (status->flag & (RX_FLAG_HT | RX_FLAG_VHT))
 222                 put_unaligned_le16(IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ,
 223                                    pos);
 224         else if (rate && rate->flags & IEEE80211_RATE_ERP_G)
 225                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
 226                                    pos);
 227         else if (rate)
 228                 put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
 229                                    pos);
 230         else
 231                 put_unaligned_le16(IEEE80211_CHAN_2GHZ, pos);
 232         pos += 2;
 233
 234         /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */
 235         if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM &&
 236             !(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
 237                 *pos = status->signal;
 238                 rthdr->it_present |=
 239                         cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL);
 240                 pos++;
 241         }
 242
 243         /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */
 244
 245         /* IEEE80211_RADIOTAP_ANTENNA */
 246         *pos = status->antenna;
 247         pos++;
 248
 249         /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */
 250
 251         /* IEEE80211_RADIOTAP_RX_FLAGS */
 252         /* ensure 2 byte alignment for the 2 byte field as required */
 253         if ((pos - (u8 *)rthdr) & 1)
 254                 *pos++ = 0;
 255         if (status->flag & RX_FLAG_FAILED_PLCP_CRC)
 256                 rx_flags |= IEEE80211_RADIOTAP_F_RX_BADPLCP;
 257         put_unaligned_le16(rx_flags, pos);
 258         pos += 2;
 259
 260         if (status->flag & RX_FLAG_HT) {
 261                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
 262                 *pos++ = local->hw.radiotap_mcs_details;
 263                 *pos = 0;
 264                 if (status->flag & RX_FLAG_SHORT_GI)
 265                         *pos |= IEEE80211_RADIOTAP_MCS_SGI;
 266                 if (status->flag & RX_FLAG_40MHZ)
 267                         *pos |= IEEE80211_RADIOTAP_MCS_BW_40;
 268                 if (status->flag & RX_FLAG_HT_GF)
 269                         *pos |= IEEE80211_RADIOTAP_MCS_FMT_GF;
 270                 pos++;
 271                 *pos++ = status->rate_idx;
 272         }
 273
 274         if (status->flag & RX_FLAG_AMPDU_DETAILS) {
 275                 u16 flags = 0;
 276
 277                 /* ensure 4 byte alignment */
 278                 while ((pos - (u8 *)rthdr) & 3)
 279                         pos++;
 280                 rthdr->it_present |=
 281                         cpu_to_le32(1 << IEEE80211_RADIOTAP_AMPDU_STATUS);
 282                 put_unaligned_le32(status->ampdu_reference, pos);
 283                 pos += 4;
 284                 if (status->flag & RX_FLAG_AMPDU_REPORT_ZEROLEN)
 285                         flags |= IEEE80211_RADIOTAP_AMPDU_REPORT_ZEROLEN;
 286                 if (status->flag & RX_FLAG_AMPDU_IS_ZEROLEN)
 287                         flags |= IEEE80211_RADIOTAP_AMPDU_IS_ZEROLEN;
 288                 if (status->flag & RX_FLAG_AMPDU_LAST_KNOWN)
 289                         flags |= IEEE80211_RADIOTAP_AMPDU_LAST_KNOWN;
 290                 if (status->flag & RX_FLAG_AMPDU_IS_LAST)
 291                         flags |= IEEE80211_RADIOTAP_AMPDU_IS_LAST;
 292                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_ERROR)
 293                         flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_ERR;
 294                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
 295                         flags |= IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_KNOWN;
 296                 put_unaligned_le16(flags, pos);
 297                 pos += 2;
 298                 if (status->flag & RX_FLAG_AMPDU_DELIM_CRC_KNOWN)
 299                         *pos++ = status->ampdu_delimiter_crc;
 300                 else
 301                         *pos++ = 0;
 302                 *pos++ = 0;
 303         }
 304
 305         if (status->flag & RX_FLAG_VHT) {
 306                 u16 known = local->hw.radiotap_vht_details;
 307
 308                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_VHT);
 309                 /* known field - how to handle 80+80? */
 310                 if (status->flag & RX_FLAG_80P80MHZ)
 311                         known &= ~IEEE80211_RADIOTAP_VHT_KNOWN_BANDWIDTH;
 312                 put_unaligned_le16(known, pos);
 313                 pos += 2;
 314                 /* flags */
 315                 if (status->flag & RX_FLAG_SHORT_GI)
 316                         *pos |= IEEE80211_RADIOTAP_VHT_FLAG_SGI;
 317                 pos++;
 318                 /* bandwidth */
 319                 if (status->flag & RX_FLAG_80MHZ)
 320                         *pos++ = 4;
 321                 else if (status->flag & RX_FLAG_80P80MHZ)
 322                         *pos++ = 0; /* marked not known above */
 323                 else if (status->flag & RX_FLAG_160MHZ)
 324                         *pos++ = 11;
 325                 else if (status->flag & RX_FLAG_40MHZ)
 326                         *pos++ = 1;
 327                 else /* 20 MHz */
 328                         *pos++ = 0;
 329                 /* MCS/NSS */
 330                 *pos = (status->rate_idx << 4) | status->vht_nss;
 331                 pos += 4;
 332                 /* coding field */
 333                 pos++;
 334                 /* group ID */
 335                 pos++;
 336                 /* partial_aid */
 337                 pos += 2;
 338         }
 339
 340         if (status->vendor_radiotap_len) {
 341                 /* ensure 2 byte alignment for the vendor field as required */
 342                 if ((pos - (u8 *)rthdr) & 1)
 343                         *pos++ = 0;
 344                 *pos++ = status->vendor_radiotap_oui[0];
 345                 *pos++ = status->vendor_radiotap_oui[1];
 346                 *pos++ = status->vendor_radiotap_oui[2];
 347                 *pos++ = status->vendor_radiotap_subns;
 348                 put_unaligned_le16(status->vendor_radiotap_len, pos);
 349                 pos += 2;
 350                 /* align the actual payload as requested */
 351                 while ((pos - (u8 *)rthdr) & (status->vendor_radiotap_align - 1))
 352                         *pos++ = 0;
 353         }
 354 }
 355
 356 /*
 357  * This function copies a received frame to all monitor interfaces and
 358  * returns a cleaned-up SKB that no longer includes the FCS nor the
 359  * radiotap header the driver might have added.
 360  */
 361 static struct sk_buff *
 362 ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb,
 363                      struct ieee80211_rate *rate)
 364 {
 365         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(origskb);
 366         struct ieee80211_sub_if_data *sdata;
 367         int needed_headroom;
 368         struct sk_buff *skb, *skb2;
 369         struct net_device *prev_dev = NULL;
 370         int present_fcs_len = 0;
 371
 372         /*
 373          * First, we may need to make a copy of the skb because
 374          *  (1) we need to modify it for radiotap (if not present), and
 375          *  (2) the other RX handlers will modify the skb we got.
 376          *
 377          * We don't need to, of course, if we aren't going to return
 378          * the SKB because it has a bad FCS/PLCP checksum.
 379          */
 380
 381         if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS)
 382                 present_fcs_len = FCS_LEN;
 383
 384         /* ensure hdr->frame_control and vendor radiotap data are in skb head */
 385         if (!pskb_may_pull(origskb, 2 + status->vendor_radiotap_len)) {
 386                 dev_kfree_skb(origskb);
 387                 return NULL;
 388         }
 389
 390         if (!local->monitors) {
 391                 if (should_drop_frame(origskb, present_fcs_len)) {
 392                         dev_kfree_skb(origskb);
 393                         return NULL;
 394                 }
 395
 396                 return remove_monitor_info(local, origskb);
 397         }
 398
 399         /* room for the radiotap header based on driver features */
 400         needed_headroom = ieee80211_rx_radiotap_space(local, status);
 401
 402         if (should_drop_frame(origskb, present_fcs_len)) {
 403                 /* only need to expand headroom if necessary */
 404                 skb = origskb;
 405                 origskb = NULL;
 406
 407                 /*
 408                  * This shouldn't trigger often because most devices have an
 409                  * RX header they pull before we get here, and that should
 410                  * be big enough for our radiotap information. We should
 411                  * probably export the length to drivers so that we can have
 412                  * them allocate enough headroom to start with.
 413                  */
 414                 if (skb_headroom(skb) < needed_headroom &&
 415                     pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC)) {
 416                         dev_kfree_skb(skb);
 417                         return NULL;
 418                 }
 419         } else {
 420                 /*
 421                  * Need to make a copy and possibly remove radiotap header
 422                  * and FCS from the original.
 423                  */
 424                 skb = skb_copy_expand(origskb, needed_headroom, 0, GFP_ATOMIC);
 425
 426                 origskb = remove_monitor_info(local, origskb);
 427
 428                 if (!skb)
 429                         return origskb;
 430         }
 431
 432         /* prepend radiotap information */
 433         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
 434                                          true);
 435
 436         skb_reset_mac_header(skb);
 437         skb->ip_summed = CHECKSUM_UNNECESSARY;
 438         skb->pkt_type = PACKET_OTHERHOST;
 439         skb->protocol = htons(ETH_P_802_2);
 440
 441         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 442                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
 443                         continue;
 444
 445                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES)
 446                         continue;
 447
 448                 if (!ieee80211_sdata_running(sdata))
 449                         continue;
 450
 451                 if (prev_dev) {
 452                         skb2 = skb_clone(skb, GFP_ATOMIC);
 453                         if (skb2) {
 454                                 skb2->dev = prev_dev;
 455                                 netif_receive_skb(skb2);
 456                         }
 457                 }
 458
 459                 prev_dev = sdata->dev;
 460                 sdata->dev->stats.rx_packets++;
 461                 sdata->dev->stats.rx_bytes += skb->len;
 462         }
 463
 464         if (prev_dev) {
 465                 skb->dev = prev_dev;
 466                 netif_receive_skb(skb);
 467         } else
 468                 dev_kfree_skb(skb);
 469
 470         return origskb;
 471 }
 472
 473 static void ieee80211_parse_qos(struct ieee80211_rx_data *rx)
 474 {
 475         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 476         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 477         int tid, seqno_idx, security_idx;
 478
 479         /* does the frame have a qos control field? */
 480         if (ieee80211_is_data_qos(hdr->frame_control)) {
 481                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 482                 /* frame has qos control */
 483                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
 484                 if (*qc & IEEE80211_QOS_CTL_A_MSDU_PRESENT)
 485                         status->rx_flags |= IEEE80211_RX_AMSDU;
 486
 487                 seqno_idx = tid;
 488                 security_idx = tid;
 489         } else {
 490                 /*
 491                  * IEEE 802.11-2007, 7.1.3.4.1 ("Sequence Number field"):
 492                  *
 493                  *      Sequence numbers for management frames, QoS data
 494                  *      frames with a broadcast/multicast address in the
 495                  *      Address 1 field, and all non-QoS data frames sent
 496                  *      by QoS STAs are assigned using an additional single
 497                  *      modulo-4096 counter, [...]
 498                  *
 499                  * We also use that counter for non-QoS STAs.
 500                  */
 501                 seqno_idx = IEEE80211_NUM_TIDS;
 502                 security_idx = 0;
 503                 if (ieee80211_is_mgmt(hdr->frame_control))
 504                         security_idx = IEEE80211_NUM_TIDS;
 505                 tid = 0;
 506         }
 507
 508         rx->seqno_idx = seqno_idx;
 509         rx->security_idx = security_idx;
 510         /* Set skb->priority to 1d tag if highest order bit of TID is not set.
 511          * For now, set skb->priority to 0 for other cases. */
 512         rx->skb->priority = (tid > 7) ? 0 : tid;
 513 }
 514
 515 /**
 516  * DOC: Packet alignment
 517  *
 518  * Drivers always need to pass packets that are aligned to two-byte boundaries
 519  * to the stack.
 520  *
 521  * Additionally, should, if possible, align the payload data in a way that
 522  * guarantees that the contained IP header is aligned to a four-byte
 523  * boundary. In the case of regular frames, this simply means aligning the
 524  * payload to a four-byte boundary (because either the IP header is directly
 525  * contained, or IV/RFC1042 headers that have a length divisible by four are
 526  * in front of it).  If the payload data is not properly aligned and the
 527  * architecture doesn't support efficient unaligned operations, mac80211
 528  * will align the data.
 529  *
 530  * With A-MSDU frames, however, the payload data address must yield two modulo
 531  * four because there are 14-byte 802.3 headers within the A-MSDU frames that
 532  * push the IP header further back to a multiple of four again. Thankfully, the
 533  * specs were sane enough this time around to require padding each A-MSDU
 534  * subframe to a length that is a multiple of four.
 535  *
 536  * Padding like Atheros hardware adds which is between the 802.11 header and
 537  * the payload is not supported, the driver is required to move the 802.11
 538  * header to be directly in front of the payload in that case.
 539  */
 540 static void ieee80211_verify_alignment(struct ieee80211_rx_data *rx)
 541 {
 542 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 543         WARN_ONCE((unsigned long)rx->skb->data & 1,
 544                   "unaligned packet at 0x%p\n", rx->skb->data);
 545 #endif
 546 }
 547
 548
 549 /* rx handlers */
 550
 551 static int ieee80211_is_unicast_robust_mgmt_frame(struct sk_buff *skb)
 552 {
 553         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 554
 555         if (skb->len < 24 || is_multicast_ether_addr(hdr->addr1))
 556                 return 0;
 557
 558         return ieee80211_is_robust_mgmt_frame(hdr);
 559 }
 560
 561
 562 static int ieee80211_is_multicast_robust_mgmt_frame(struct sk_buff *skb)
 563 {
 564         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 565
 566         if (skb->len < 24 || !is_multicast_ether_addr(hdr->addr1))
 567                 return 0;
 568
 569         return ieee80211_is_robust_mgmt_frame(hdr);
 570 }
 571
 572
 573 /* Get the BIP key index from MMIE; return -1 if this is not a BIP frame */
 574 static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
 575 {
 576         struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data;
 577         struct ieee80211_mmie *mmie;
 578
 579         if (skb->len < 24 + sizeof(*mmie) || !is_multicast_ether_addr(hdr->da))
 580                 return -1;
 581
 582         if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *) hdr))
 583                 return -1; /* not a robust management frame */
 584
 585         mmie = (struct ieee80211_mmie *)
 586                 (skb->data + skb->len - sizeof(*mmie));
 587         if (mmie->element_id != WLAN_EID_MMIE ||
 588             mmie->length != sizeof(*mmie) - 2)
 589                 return -1;
 590
 591         return le16_to_cpu(mmie->key_id);
 592 }
 593
 594 static ieee80211_rx_result ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
 595 {
 596         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 597         char *dev_addr = rx->sdata->vif.addr;
 598
 599         if (ieee80211_is_data(hdr->frame_control)) {
 600                 if (is_multicast_ether_addr(hdr->addr1)) {
 601                         if (ieee80211_has_tods(hdr->frame_control) ||
 602                             !ieee80211_has_fromds(hdr->frame_control))
 603                                 return RX_DROP_MONITOR;
 604                         if (ether_addr_equal(hdr->addr3, dev_addr))
 605                                 return RX_DROP_MONITOR;
 606                 } else {
 607                         if (!ieee80211_has_a4(hdr->frame_control))
 608                                 return RX_DROP_MONITOR;
 609                         if (ether_addr_equal(hdr->addr4, dev_addr))
 610                                 return RX_DROP_MONITOR;
 611                 }
 612         }
 613
 614         /* If there is not an established peer link and this is not a peer link
 615          * establisment frame, beacon or probe, drop the frame.
 616          */
 617
 618         if (!rx->sta || sta_plink_state(rx->sta) != NL80211_PLINK_ESTAB) {
 619                 struct ieee80211_mgmt *mgmt;
 620
 621                 if (!ieee80211_is_mgmt(hdr->frame_control))
 622                         return RX_DROP_MONITOR;
 623
 624                 if (ieee80211_is_action(hdr->frame_control)) {
 625                         u8 category;
 626
 627                         /* make sure category field is present */
 628                         if (rx->skb->len < IEEE80211_MIN_ACTION_SIZE)
 629                                 return RX_DROP_MONITOR;
 630
 631                         mgmt = (struct ieee80211_mgmt *)hdr;
 632                         category = mgmt->u.action.category;
 633                         if (category != WLAN_CATEGORY_MESH_ACTION &&
 634                             category != WLAN_CATEGORY_SELF_PROTECTED)
 635                                 return RX_DROP_MONITOR;
 636                         return RX_CONTINUE;
 637                 }
 638
 639                 if (ieee80211_is_probe_req(hdr->frame_control) ||
 640                     ieee80211_is_probe_resp(hdr->frame_control) ||
 641                     ieee80211_is_beacon(hdr->frame_control) ||
 642                     ieee80211_is_auth(hdr->frame_control))
 643                         return RX_CONTINUE;
 644
 645                 return RX_DROP_MONITOR;
 646         }
 647
 648         return RX_CONTINUE;
 649 }
 650
 651 static void ieee80211_release_reorder_frame(struct ieee80211_sub_if_data *sdata,
 652                                             struct tid_ampdu_rx *tid_agg_rx,
 653                                             int index,
 654                                             struct sk_buff_head *frames)
 655 {
 656         struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
 657         struct ieee80211_rx_status *status;
 658
 659         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 660
 661         if (!skb)
 662                 goto no_frame;
 663
 664         /* release the frame from the reorder ring buffer */
 665         tid_agg_rx->stored_mpdu_num--;
 666         tid_agg_rx->reorder_buf[index] = NULL;
 667         status = IEEE80211_SKB_RXCB(skb);
 668         status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE;
 669         __skb_queue_tail(frames, skb);
 670
 671 no_frame:
 672         tid_agg_rx->head_seq_num = ieee80211_sn_inc(tid_agg_rx->head_seq_num);
 673 }
 674
 675 static void ieee80211_release_reorder_frames(struct ieee80211_sub_if_data *sdata,
 676                                              struct tid_ampdu_rx *tid_agg_rx,
 677                                              u16 head_seq_num,
 678                                              struct sk_buff_head *frames)
 679 {
 680         int index;
 681
 682         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 683
 684         while (ieee80211_sn_less(tid_agg_rx->head_seq_num, head_seq_num)) {
 685                 index = ieee80211_sn_sub(tid_agg_rx->head_seq_num,
 686                                          tid_agg_rx->ssn) %
 687                                                         tid_agg_rx->buf_size;
 688                 ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
 689                                                 frames);
 690         }
 691 }
 692
 693 /*
 694  * Timeout (in jiffies) for skb's that are waiting in the RX reorder buffer. If
 695  * the skb was added to the buffer longer than this time ago, the earlier
 696  * frames that have not yet been received are assumed to be lost and the skb
 697  * can be released for processing. This may also release other skb's from the
 698  * reorder buffer if there are no additional gaps between the frames.
 699  *
 700  * Callers must hold tid_agg_rx->reorder_lock.
 701  */
 702 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
 703
 704 static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata,
 705                                           struct tid_ampdu_rx *tid_agg_rx,
 706                                           struct sk_buff_head *frames)
 707 {
 708         int index, j;
 709
 710         lockdep_assert_held(&tid_agg_rx->reorder_lock);
 711
 712         /* release the buffer until next missing frame */
 713         index = ieee80211_sn_sub(tid_agg_rx->head_seq_num,
 714                                  tid_agg_rx->ssn) % tid_agg_rx->buf_size;
 715         if (!tid_agg_rx->reorder_buf[index] &&
 716             tid_agg_rx->stored_mpdu_num) {
 717                 /*
 718                  * No buffers ready to be released, but check whether any
 719                  * frames in the reorder buffer have timed out.
 720                  */
 721                 int skipped = 1;
 722                 for (j = (index + 1) % tid_agg_rx->buf_size; j != index;
 723                      j = (j + 1) % tid_agg_rx->buf_size) {
 724                         if (!tid_agg_rx->reorder_buf[j]) {
 725                                 skipped++;
 726                                 continue;
 727                         }
 728                         if (skipped &&
 729                             !time_after(jiffies, tid_agg_rx->reorder_time[j] +
 730                                         HT_RX_REORDER_BUF_TIMEOUT))
 731                                 goto set_release_timer;
 732
 733                         ht_dbg_ratelimited(sdata,
 734                                            "release an RX reorder frame due to timeout on earlier frames\n");
 735                         ieee80211_release_reorder_frame(sdata, tid_agg_rx, j,
 736                                                         frames);
 737
 738                         /*
 739                          * Increment the head seq# also for the skipped slots.
 740                          */
 741                         tid_agg_rx->head_seq_num =
 742                                 (tid_agg_rx->head_seq_num +
 743                                  skipped) & IEEE80211_SN_MASK;
 744                         skipped = 0;
 745                 }
 746         } else while (tid_agg_rx->reorder_buf[index]) {
 747                 ieee80211_release_reorder_frame(sdata, tid_agg_rx, index,
 748                                                 frames);
 749                 index = ieee80211_sn_sub(tid_agg_rx->head_seq_num,
 750                                          tid_agg_rx->ssn) %
 751                                                         tid_agg_rx->buf_size;
 752         }
 753
 754         if (tid_agg_rx->stored_mpdu_num) {
 755                 j = index = ieee80211_sn_sub(tid_agg_rx->head_seq_num,
 756                                              tid_agg_rx->ssn) %
 757                                                         tid_agg_rx->buf_size;
 758
 759                 for (; j != (index - 1) % tid_agg_rx->buf_size;
 760                      j = (j + 1) % tid_agg_rx->buf_size) {
 761                         if (tid_agg_rx->reorder_buf[j])
 762                                 break;
 763                 }
 764
 765  set_release_timer:
 766
 767                 mod_timer(&tid_agg_rx->reorder_timer,
 768                           tid_agg_rx->reorder_time[j] + 1 +
 769                           HT_RX_REORDER_BUF_TIMEOUT);
 770         } else {
 771                 del_timer(&tid_agg_rx->reorder_timer);
 772         }
 773 }
 774
 775 /*
 776  * As this function belongs to the RX path it must be under
 777  * rcu_read_lock protection. It returns false if the frame
 778  * can be processed immediately, true if it was consumed.
 779  */
 780 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_sub_if_data *sdata,
 781                                              struct tid_ampdu_rx *tid_agg_rx,
 782                                              struct sk_buff *skb,
 783                                              struct sk_buff_head *frames)
 784 {
 785         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 786         u16 sc = le16_to_cpu(hdr->seq_ctrl);
 787         u16 mpdu_seq_num = (sc & IEEE80211_SCTL_SEQ) >> 4;
 788         u16 head_seq_num, buf_size;
 789         int index;
 790         bool ret = true;
 791
 792         spin_lock(&tid_agg_rx->reorder_lock);
 793
 794         buf_size = tid_agg_rx->buf_size;
 795         head_seq_num = tid_agg_rx->head_seq_num;
 796
 797         /* frame with out of date sequence number */
 798         if (ieee80211_sn_less(mpdu_seq_num, head_seq_num)) {
 799                 dev_kfree_skb(skb);
 800                 goto out;
 801         }
 802
 803         /*
 804          * If frame the sequence number exceeds our buffering window
 805          * size release some previous frames to make room for this one.
 806          */
 807         if (!ieee80211_sn_less(mpdu_seq_num, head_seq_num + buf_size)) {
 808                 head_seq_num = ieee80211_sn_inc(
 809                                 ieee80211_sn_sub(mpdu_seq_num, buf_size));
 810                 /* release stored frames up to new head to stack */
 811                 ieee80211_release_reorder_frames(sdata, tid_agg_rx,
 812                                                  head_seq_num, frames);
 813         }
 814
 815         /* Now the new frame is always in the range of the reordering buffer */
 816
 817         index = ieee80211_sn_sub(mpdu_seq_num,
 818                                  tid_agg_rx->ssn) % tid_agg_rx->buf_size;
 819
 820         /* check if we already stored this frame */
 821         if (tid_agg_rx->reorder_buf[index]) {
 822                 dev_kfree_skb(skb);
 823                 goto out;
 824         }
 825
 826         /*
 827          * If the current MPDU is in the right order and nothing else
 828          * is stored we can process it directly, no need to buffer it.
 829          * If it is first but there's something stored, we may be able
 830          * to release frames after this one.
 831          */
 832         if (mpdu_seq_num == tid_agg_rx->head_seq_num &&
 833             tid_agg_rx->stored_mpdu_num == 0) {
 834                 tid_agg_rx->head_seq_num =
 835                         ieee80211_sn_inc(tid_agg_rx->head_seq_num);
 836                 ret = false;
 837                 goto out;
 838         }
 839
 840         /* put the frame in the reordering buffer */
 841         tid_agg_rx->reorder_buf[index] = skb;
 842         tid_agg_rx->reorder_time[index] = jiffies;
 843         tid_agg_rx->stored_mpdu_num++;
 844         ieee80211_sta_reorder_release(sdata, tid_agg_rx, frames);
 845
 846  out:
 847         spin_unlock(&tid_agg_rx->reorder_lock);
 848         return ret;
 849 }
 850
 851 /*
 852  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
 853  * true if the MPDU was buffered, false if it should be processed.
 854  */
 855 static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
 856                                        struct sk_buff_head *frames)
 857 {
 858         struct sk_buff *skb = rx->skb;
 859         struct ieee80211_local *local = rx->local;
 860         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 861         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 862         struct sta_info *sta = rx->sta;
 863         struct tid_ampdu_rx *tid_agg_rx;
 864         u16 sc;
 865         u8 tid, ack_policy;
 866
 867         if (!ieee80211_is_data_qos(hdr->frame_control) ||
 868             is_multicast_ether_addr(hdr->addr1))
 869                 goto dont_reorder;
 870
 871         /*
 872          * filter the QoS data rx stream according to
 873          * STA/TID and check if this STA/TID is on aggregation
 874          */
 875
 876         if (!sta)
 877                 goto dont_reorder;
 878
 879         ack_policy = *ieee80211_get_qos_ctl(hdr) &
 880                      IEEE80211_QOS_CTL_ACK_POLICY_MASK;
 881         tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
 882
 883         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
 884         if (!tid_agg_rx)
 885                 goto dont_reorder;
 886
 887         /* qos null data frames are excluded */
 888         if (unlikely(hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_NULLFUNC)))
 889                 goto dont_reorder;
 890
 891         /* not part of a BA session */
 892         if (ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_BLOCKACK &&
 893             ack_policy != IEEE80211_QOS_CTL_ACK_POLICY_NORMAL)
 894                 goto dont_reorder;
 895
 896         /* not actually part of this BA session */
 897         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
 898                 goto dont_reorder;
 899
 900         /* new, potentially un-ordered, ampdu frame - process it */
 901
 902         /* reset session timer */
 903         if (tid_agg_rx->timeout)
 904                 tid_agg_rx->last_rx = jiffies;
 905
 906         /* if this mpdu is fragmented - terminate rx aggregation session */
 907         sc = le16_to_cpu(hdr->seq_ctrl);
 908         if (sc & IEEE80211_SCTL_FRAG) {
 909                 skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
 910                 skb_queue_tail(&rx->sdata->skb_queue, skb);
 911                 ieee80211_queue_work(&local->hw, &rx->sdata->work);
 912                 return;
 913         }
 914
 915         /*
 916          * No locking needed -- we will only ever process one
 917          * RX packet at a time, and thus own tid_agg_rx. All
 918          * other code manipulating it needs to (and does) make
 919          * sure that we cannot get to it any more before doing
 920          * anything with it.
 921          */
 922         if (ieee80211_sta_manage_reorder_buf(rx->sdata, tid_agg_rx, skb,
 923                                              frames))
 924                 return;
 925
 926  dont_reorder:
 927         __skb_queue_tail(frames, skb);
 928 }
 929
 930 static ieee80211_rx_result debug_noinline
 931 ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
 932 {
 933         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 934         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 935
 936         /*
 937          * Drop duplicate 802.11 retransmissions
 938          * (IEEE 802.11-2012: 9.3.2.10 "Duplicate detection and recovery")
 939          */
 940         if (rx->skb->len >= 24 && rx->sta &&
 941             !ieee80211_is_ctl(hdr->frame_control) &&
 942             !ieee80211_is_qos_nullfunc(hdr->frame_control) &&
 943             !is_multicast_ether_addr(hdr->addr1)) {
 944                 if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
 945                              rx->sta->last_seq_ctrl[rx->seqno_idx] ==
 946                              hdr->seq_ctrl)) {
 947                         if (status->rx_flags & IEEE80211_RX_RA_MATCH) {
 948                                 rx->local->dot11FrameDuplicateCount++;
 949                                 rx->sta->num_duplicates++;
 950                         }
 951                         return RX_DROP_UNUSABLE;
 952                 } else
 953                         rx->sta->last_seq_ctrl[rx->seqno_idx] = hdr->seq_ctrl;
 954         }
 955
 956         if (unlikely(rx->skb->len < 16)) {
 957                 I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
 958                 return RX_DROP_MONITOR;
 959         }
 960
 961         /* Drop disallowed frame classes based on STA auth/assoc state;
 962          * IEEE 802.11, Chap 5.5.
 963          *
 964          * mac80211 filters only based on association state, i.e. it drops
 965          * Class 3 frames from not associated stations. hostapd sends
 966          * deauth/disassoc frames when needed. In addition, hostapd is
 967          * responsible for filtering on both auth and assoc states.
 968          */
 969
 970         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
 971                 return ieee80211_rx_mesh_check(rx);
 972
 973         if (unlikely((ieee80211_is_data(hdr->frame_control) ||
 974                       ieee80211_is_pspoll(hdr->frame_control)) &&
 975                      rx->sdata->vif.type != NL80211_IFTYPE_ADHOC &&
 976                      rx->sdata->vif.type != NL80211_IFTYPE_WDS &&
 977                      (!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_ASSOC)))) {
 978                 /*
 979                  * accept port control frames from the AP even when it's not
 980                  * yet marked ASSOC to prevent a race where we don't set the
 981                  * assoc bit quickly enough before it sends the first frame
 982                  */
 983                 if (rx->sta && rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
 984                     ieee80211_is_data_present(hdr->frame_control)) {
 985                         unsigned int hdrlen;
 986                         __be16 ethertype;
 987
 988                         hdrlen = ieee80211_hdrlen(hdr->frame_control);
 989
 990                         if (rx->skb->len < hdrlen + 8)
 991                                 return RX_DROP_MONITOR;
 992
 993                         skb_copy_bits(rx->skb, hdrlen + 6, &ethertype, 2);
 994                         if (ethertype == rx->sdata->control_port_protocol)
 995                                 return RX_CONTINUE;
 996                 }
 997
 998                 if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
 999                     cfg80211_rx_spurious_frame(rx->sdata->dev,
1000                                                hdr->addr2,
1001                                                GFP_ATOMIC))
1002                         return RX_DROP_UNUSABLE;
1003
1004                 return RX_DROP_MONITOR;
1005         }
1006
1007         return RX_CONTINUE;
1008 }
1009
1010
1011 static ieee80211_rx_result debug_noinline
1012 ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
1013 {
1014         struct sk_buff *skb = rx->skb;
1015         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1016         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1017         int keyidx;
1018         int hdrlen;
1019         ieee80211_rx_result result = RX_DROP_UNUSABLE;
1020         struct ieee80211_key *sta_ptk = NULL;
1021         int mmie_keyidx = -1;
1022         __le16 fc;
1023
1024         /*
1025          * Key selection 101
1026          *
1027          * There are four types of keys:
1028          *  - GTK (group keys)
1029          *  - IGTK (group keys for management frames)
1030          *  - PTK (pairwise keys)
1031          *  - STK (station-to-station pairwise keys)
1032          *
1033          * When selecting a key, we have to distinguish between multicast
1034          * (including broadcast) and unicast frames, the latter can only
1035          * use PTKs and STKs while the former always use GTKs and IGTKs.
1036          * Unless, of course, actual WEP keys ("pre-RSNA") are used, then
1037          * unicast frames can also use key indices like GTKs. Hence, if we
1038          * don't have a PTK/STK we check the key index for a WEP key.
1039          *
1040          * Note that in a regular BSS, multicast frames are sent by the
1041          * AP only, associated stations unicast the frame to the AP first
1042          * which then multicasts it on their behalf.
1043          *
1044          * There is also a slight problem in IBSS mode: GTKs are negotiated
1045          * with each station, that is something we don't currently handle.
1046          * The spec seems to expect that one negotiates the same key with
1047          * every station but there's no such requirement; VLANs could be
1048          * possible.
1049          */
1050
1051         /*
1052          * No point in finding a key and decrypting if the frame is neither
1053          * addressed to us nor a multicast frame.
1054          */
1055         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1056                 return RX_CONTINUE;
1057
1058         /* start without a key */
1059         rx->key = NULL;
1060
1061         if (rx->sta)
1062                 sta_ptk = rcu_dereference(rx->sta->ptk);
1063
1064         fc = hdr->frame_control;
1065
1066         if (!ieee80211_has_protected(fc))
1067                 mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
1068
1069         if (!is_multicast_ether_addr(hdr->addr1) && sta_ptk) {
1070                 rx->key = sta_ptk;
1071                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1072                     (status->flag & RX_FLAG_IV_STRIPPED))
1073                         return RX_CONTINUE;
1074                 /* Skip decryption if the frame is not protected. */
1075                 if (!ieee80211_has_protected(fc))
1076                         return RX_CONTINUE;
1077         } else if (mmie_keyidx >= 0) {
1078                 /* Broadcast/multicast robust management frame / BIP */
1079                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1080                     (status->flag & RX_FLAG_IV_STRIPPED))
1081                         return RX_CONTINUE;
1082
1083                 if (mmie_keyidx < NUM_DEFAULT_KEYS ||
1084                     mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
1085                         return RX_DROP_MONITOR; /* unexpected BIP keyidx */
1086                 if (rx->sta)
1087                         rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]);
1088                 if (!rx->key)
1089                         rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
1090         } else if (!ieee80211_has_protected(fc)) {
1091                 /*
1092                  * The frame was not protected, so skip decryption. However, we
1093                  * need to set rx->key if there is a key that could have been
1094                  * used so that the frame may be dropped if encryption would
1095                  * have been expected.
1096                  */
1097                 struct ieee80211_key *key = NULL;
1098                 struct ieee80211_sub_if_data *sdata = rx->sdata;
1099                 int i;
1100
1101                 if (ieee80211_is_mgmt(fc) &&
1102                     is_multicast_ether_addr(hdr->addr1) &&
1103                     (key = rcu_dereference(rx->sdata->default_mgmt_key)))
1104                         rx->key = key;
1105                 else {
1106                         if (rx->sta) {
1107                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1108                                         key = rcu_dereference(rx->sta->gtk[i]);
1109                                         if (key)
1110                                                 break;
1111                                 }
1112                         }
1113                         if (!key) {
1114                                 for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
1115                                         key = rcu_dereference(sdata->keys[i]);
1116                                         if (key)
1117                                                 break;
1118                                 }
1119                         }
1120                         if (key)
1121                                 rx->key = key;
1122                 }
1123                 return RX_CONTINUE;
1124         } else {
1125                 u8 keyid;
1126                 /*
1127                  * The device doesn't give us the IV so we won't be
1128                  * able to look up the key. That's ok though, we
1129                  * don't need to decrypt the frame, we just won't
1130                  * be able to keep statistics accurate.
1131                  * Except for key threshold notifications, should
1132                  * we somehow allow the driver to tell us which key
1133                  * the hardware used if this flag is set?
1134                  */
1135                 if ((status->flag & RX_FLAG_DECRYPTED) &&
1136                     (status->flag & RX_FLAG_IV_STRIPPED))
1137                         return RX_CONTINUE;
1138
1139                 hdrlen = ieee80211_hdrlen(fc);
1140
1141                 if (rx->skb->len < 8 + hdrlen)
1142                         return RX_DROP_UNUSABLE; /* TODO: count this? */
1143
1144                 /*
1145                  * no need to call ieee80211_wep_get_keyidx,
1146                  * it verifies a bunch of things we've done already
1147                  */
1148                 skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
1149                 keyidx = keyid >> 6;
1150
1151                 /* check per-station GTK first, if multicast packet */
1152                 if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
1153                         rx->key = rcu_dereference(rx->sta->gtk[keyidx]);
1154
1155                 /* if not found, try default key */
1156                 if (!rx->key) {
1157                         rx->key = rcu_dereference(rx->sdata->keys[keyidx]);
1158
1159                         /*
1160                          * RSNA-protected unicast frames should always be
1161                          * sent with pairwise or station-to-station keys,
1162                          * but for WEP we allow using a key index as well.
1163                          */
1164                         if (rx->key &&
1165                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP40 &&
1166                             rx->key->conf.cipher != WLAN_CIPHER_SUITE_WEP104 &&
1167                             !is_multicast_ether_addr(hdr->addr1))
1168                                 rx->key = NULL;
1169                 }
1170         }
1171
1172         if (rx->key) {
1173                 if (unlikely(rx->key->flags & KEY_FLAG_TAINTED))
1174                         return RX_DROP_MONITOR;
1175
1176                 rx->key->tx_rx_count++;
1177                 /* TODO: add threshold stuff again */
1178         } else {
1179                 return RX_DROP_MONITOR;
1180         }
1181
1182         switch (rx->key->conf.cipher) {
1183         case WLAN_CIPHER_SUITE_WEP40:
1184         case WLAN_CIPHER_SUITE_WEP104:
1185                 result = ieee80211_crypto_wep_decrypt(rx);
1186                 break;
1187         case WLAN_CIPHER_SUITE_TKIP:
1188                 result = ieee80211_crypto_tkip_decrypt(rx);
1189                 break;
1190         case WLAN_CIPHER_SUITE_CCMP:
1191                 result = ieee80211_crypto_ccmp_decrypt(rx);
1192                 break;
1193         case WLAN_CIPHER_SUITE_AES_CMAC:
1194                 result = ieee80211_crypto_aes_cmac_decrypt(rx);
1195                 break;
1196         default:
1197                 /*
1198                  * We can reach here only with HW-only algorithms
1199                  * but why didn't it decrypt the frame?!
1200                  */
1201                 return RX_DROP_UNUSABLE;
1202         }
1203
1204         /* the hdr variable is invalid after the decrypt handlers */
1205
1206         /* either the frame has been decrypted or will be dropped */
1207         status->flag |= RX_FLAG_DECRYPTED;
1208
1209         return result;
1210 }
1211
1212 static ieee80211_rx_result debug_noinline
1213 ieee80211_rx_h_check_more_data(struct ieee80211_rx_data *rx)
1214 {
1215         struct ieee80211_local *local;
1216         struct ieee80211_hdr *hdr;
1217         struct sk_buff *skb;
1218
1219         local = rx->local;
1220         skb = rx->skb;
1221         hdr = (struct ieee80211_hdr *) skb->data;
1222
1223         if (!local->pspolling)
1224                 return RX_CONTINUE;
1225
1226         if (!ieee80211_has_fromds(hdr->frame_control))
1227                 /* this is not from AP */
1228                 return RX_CONTINUE;
1229
1230         if (!ieee80211_is_data(hdr->frame_control))
1231                 return RX_CONTINUE;
1232
1233         if (!ieee80211_has_moredata(hdr->frame_control)) {
1234                 /* AP has no more frames buffered for us */
1235                 local->pspolling = false;
1236                 return RX_CONTINUE;
1237         }
1238
1239         /* more data bit is set, let's request a new frame from the AP */
1240         ieee80211_send_pspoll(local, rx->sdata);
1241
1242         return RX_CONTINUE;
1243 }
1244
1245 static void sta_ps_start(struct sta_info *sta)
1246 {
1247         struct ieee80211_sub_if_data *sdata = sta->sdata;
1248         struct ieee80211_local *local = sdata->local;
1249         struct ps_data *ps;
1250
1251         if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
1252             sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1253                 ps = &sdata->bss->ps;
1254         else
1255                 return;
1256
1257         atomic_inc(&ps->num_sta_ps);
1258         set_sta_flag(sta, WLAN_STA_PS_STA);
1259         if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
1260                 drv_sta_notify(local, sdata, STA_NOTIFY_SLEEP, &sta->sta);
1261         ps_dbg(sdata, "STA %pM aid %d enters power save mode\n",
1262                sta->sta.addr, sta->sta.aid);
1263 }
1264
1265 static void sta_ps_end(struct sta_info *sta)
1266 {
1267         ps_dbg(sta->sdata, "STA %pM aid %d exits power save mode\n",
1268                sta->sta.addr, sta->sta.aid);
1269
1270         if (test_sta_flag(sta, WLAN_STA_PS_DRIVER)) {
1271                 ps_dbg(sta->sdata, "STA %pM aid %d driver-ps-blocked\n",
1272                        sta->sta.addr, sta->sta.aid);
1273                 return;
1274         }
1275
1276         ieee80211_sta_ps_deliver_wakeup(sta);
1277 }
1278
1279 int ieee80211_sta_ps_transition(struct ieee80211_sta *sta, bool start)
1280 {
1281         struct sta_info *sta_inf = container_of(sta, struct sta_info, sta);
1282         bool in_ps;
1283
1284         WARN_ON(!(sta_inf->local->hw.flags & IEEE80211_HW_AP_LINK_PS));
1285
1286         /* Don't let the same PS state be set twice */
1287         in_ps = test_sta_flag(sta_inf, WLAN_STA_PS_STA);
1288         if ((start && in_ps) || (!start && !in_ps))
1289                 return -EINVAL;
1290
1291         if (start)
1292                 sta_ps_start(sta_inf);
1293         else
1294                 sta_ps_end(sta_inf);
1295
1296         return 0;
1297 }
1298 EXPORT_SYMBOL(ieee80211_sta_ps_transition);
1299
1300 static ieee80211_rx_result debug_noinline
1301 ieee80211_rx_h_uapsd_and_pspoll(struct ieee80211_rx_data *rx)
1302 {
1303         struct ieee80211_sub_if_data *sdata = rx->sdata;
1304         struct ieee80211_hdr *hdr = (void *)rx->skb->data;
1305         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1306         int tid, ac;
1307
1308         if (!rx->sta || !(status->rx_flags & IEEE80211_RX_RA_MATCH))
1309                 return RX_CONTINUE;
1310
1311         if (sdata->vif.type != NL80211_IFTYPE_AP &&
1312             sdata->vif.type != NL80211_IFTYPE_AP_VLAN)
1313                 return RX_CONTINUE;
1314
1315         /*
1316          * The device handles station powersave, so don't do anything about
1317          * uAPSD and PS-Poll frames (the latter shouldn't even come up from
1318          * it to mac80211 since they're handled.)
1319          */
1320         if (sdata->local->hw.flags & IEEE80211_HW_AP_LINK_PS)
1321                 return RX_CONTINUE;
1322
1323         /*
1324          * Don't do anything if the station isn't already asleep. In
1325          * the uAPSD case, the station will probably be marked asleep,
1326          * in the PS-Poll case the station must be confused ...
1327          */
1328         if (!test_sta_flag(rx->sta, WLAN_STA_PS_STA))
1329                 return RX_CONTINUE;
1330
1331         if (unlikely(ieee80211_is_pspoll(hdr->frame_control))) {
1332                 if (!test_sta_flag(rx->sta, WLAN_STA_SP)) {
1333                         if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1334                                 ieee80211_sta_ps_deliver_poll_response(rx->sta);
1335                         else
1336                                 set_sta_flag(rx->sta, WLAN_STA_PSPOLL);
1337                 }
1338
1339                 /* Free PS Poll skb here instead of returning RX_DROP that would
1340                  * count as an dropped frame. */
1341                 dev_kfree_skb(rx->skb);
1342
1343                 return RX_QUEUED;
1344         } else if (!ieee80211_has_morefrags(hdr->frame_control) &&
1345                    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1346                    ieee80211_has_pm(hdr->frame_control) &&
1347                    (ieee80211_is_data_qos(hdr->frame_control) ||
1348                     ieee80211_is_qos_nullfunc(hdr->frame_control))) {
1349                 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
1350                 ac = ieee802_1d_to_ac[tid & 7];
1351
1352                 /*
1353                  * If this AC is not trigger-enabled do nothing.
1354                  *
1355                  * NB: This could/should check a separate bitmap of trigger-
1356                  * enabled queues, but for now we only implement uAPSD w/o
1357                  * TSPEC changes to the ACs, so they're always the same.
1358                  */
1359                 if (!(rx->sta->sta.uapsd_queues & BIT(ac)))
1360                         return RX_CONTINUE;
1361
1362                 /* if we are in a service period, do nothing */
1363                 if (test_sta_flag(rx->sta, WLAN_STA_SP))
1364                         return RX_CONTINUE;
1365
1366                 if (!test_sta_flag(rx->sta, WLAN_STA_PS_DRIVER))
1367                         ieee80211_sta_ps_deliver_uapsd(rx->sta);
1368                 else
1369                         set_sta_flag(rx->sta, WLAN_STA_UAPSD);
1370         }
1371
1372         return RX_CONTINUE;
1373 }
1374
1375 static ieee80211_rx_result debug_noinline
1376 ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
1377 {
1378         struct sta_info *sta = rx->sta;
1379         struct sk_buff *skb = rx->skb;
1380         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1381         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1382
1383         if (!sta)
1384                 return RX_CONTINUE;
1385
1386         /*
1387          * Update last_rx only for IBSS packets which are for the current
1388          * BSSID and for station already AUTHORIZED to avoid keeping the
1389          * current IBSS network alive in cases where other STAs start
1390          * using different BSSID. This will also give the station another
1391          * chance to restart the authentication/authorization in case
1392          * something went wrong the first time.
1393          */
1394         if (rx->sdata->vif.type == NL80211_IFTYPE_ADHOC) {
1395                 u8 *bssid = ieee80211_get_bssid(hdr, rx->skb->len,
1396                                                 NL80211_IFTYPE_ADHOC);
1397                 if (ether_addr_equal(bssid, rx->sdata->u.ibss.bssid) &&
1398                     test_sta_flag(sta, WLAN_STA_AUTHORIZED)) {
1399                         sta->last_rx = jiffies;
1400                         if (ieee80211_is_data(hdr->frame_control)) {
1401                                 sta->last_rx_rate_idx = status->rate_idx;
1402                                 sta->last_rx_rate_flag = status->flag;
1403                                 sta->last_rx_rate_vht_nss = status->vht_nss;
1404                         }
1405                 }
1406         } else if (!is_multicast_ether_addr(hdr->addr1)) {
1407                 /*
1408                  * Mesh beacons will update last_rx when if they are found to
1409                  * match the current local configuration when processed.
1410                  */
1411                 sta->last_rx = jiffies;
1412                 if (ieee80211_is_data(hdr->frame_control)) {
1413                         sta->last_rx_rate_idx = status->rate_idx;
1414                         sta->last_rx_rate_flag = status->flag;
1415                         sta->last_rx_rate_vht_nss = status->vht_nss;
1416                 }
1417         }
1418
1419         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
1420                 return RX_CONTINUE;
1421
1422         if (rx->sdata->vif.type == NL80211_IFTYPE_STATION)
1423                 ieee80211_sta_rx_notify(rx->sdata, hdr);
1424
1425         sta->rx_fragments++;
1426         sta->rx_bytes += rx->skb->len;
1427         if (!(status->flag & RX_FLAG_NO_SIGNAL_VAL)) {
1428                 sta->last_signal = status->signal;
1429                 ewma_add(&sta->avg_signal, -status->signal);
1430         }
1431
1432         /*
1433          * Change STA power saving mode only at the end of a frame
1434          * exchange sequence.
1435          */
1436         if (!(sta->local->hw.flags & IEEE80211_HW_AP_LINK_PS) &&
1437             !ieee80211_has_morefrags(hdr->frame_control) &&
1438             !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
1439             (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1440              rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
1441                 if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
1442                         /*
1443                          * Ignore doze->wake transitions that are
1444                          * indicated by non-data frames, the standard
1445                          * is unclear here, but for example going to
1446                          * PS mode and then scanning would cause a
1447                          * doze->wake transition for the probe request,
1448                          * and that is clearly undesirable.
1449                          */
1450                         if (ieee80211_is_data(hdr->frame_control) &&
1451                             !ieee80211_has_pm(hdr->frame_control))
1452                                 sta_ps_end(sta);
1453                 } else {
1454                         if (ieee80211_has_pm(hdr->frame_control))
1455                                 sta_ps_start(sta);
1456                 }
1457         }
1458
1459         /* mesh power save support */
1460         if (ieee80211_vif_is_mesh(&rx->sdata->vif))
1461                 ieee80211_mps_rx_h_sta_process(sta, hdr);
1462
1463         /*
1464          * Drop (qos-)data::nullfunc frames silently, since they
1465          * are used only to control station power saving mode.
1466          */
1467         if (ieee80211_is_nullfunc(hdr->frame_control) ||
1468             ieee80211_is_qos_nullfunc(hdr->frame_control)) {
1469                 I802_DEBUG_INC(rx->local->rx_handlers_drop_nullfunc);
1470
1471                 /*
1472                  * If we receive a 4-addr nullfunc frame from a STA
1473                  * that was not moved to a 4-addr STA vlan yet send
1474                  * the event to userspace and for older hostapd drop
1475                  * the frame to the monitor interface.
1476                  */
1477                 if (ieee80211_has_a4(hdr->frame_control) &&
1478                     (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
1479                      (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1480                       !rx->sdata->u.vlan.sta))) {
1481                         if (!test_and_set_sta_flag(sta, WLAN_STA_4ADDR_EVENT))
1482                                 cfg80211_rx_unexpected_4addr_frame(
1483                                         rx->sdata->dev, sta->sta.addr,
1484                                         GFP_ATOMIC);
1485                         return RX_DROP_MONITOR;
1486                 }
1487                 /*
1488                  * Update counter and free packet here to avoid
1489                  * counting this as a dropped packed.
1490                  */
1491                 sta->rx_packets++;
1492                 dev_kfree_skb(rx->skb);
1493                 return RX_QUEUED;
1494         }
1495
1496         return RX_CONTINUE;
1497 } /* ieee80211_rx_h_sta_process */
1498
1499 static inline struct ieee80211_fragment_entry *
1500 ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
1501                          unsigned int frag, unsigned int seq, int rx_queue,
1502                          struct sk_buff **skb)
1503 {
1504         struct ieee80211_fragment_entry *entry;
1505
1506         entry = &sdata->fragments[sdata->fragment_next++];
1507         if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
1508                 sdata->fragment_next = 0;
1509
1510         if (!skb_queue_empty(&entry->skb_list))
1511                 __skb_queue_purge(&entry->skb_list);
1512
1513         __skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
1514         *skb = NULL;
1515         entry->first_frag_time = jiffies;
1516         entry->seq = seq;
1517         entry->rx_queue = rx_queue;
1518         entry->last_frag = frag;
1519         entry->ccmp = 0;
1520         entry->extra_len = 0;
1521
1522         return entry;
1523 }
1524
1525 static inline struct ieee80211_fragment_entry *
1526 ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
1527                           unsigned int frag, unsigned int seq,
1528                           int rx_queue, struct ieee80211_hdr *hdr)
1529 {
1530         struct ieee80211_fragment_entry *entry;
1531         int i, idx;
1532
1533         idx = sdata->fragment_next;
1534         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
1535                 struct ieee80211_hdr *f_hdr;
1536
1537                 idx--;
1538                 if (idx < 0)
1539                         idx = IEEE80211_FRAGMENT_MAX - 1;
1540
1541                 entry = &sdata->fragments[idx];
1542                 if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
1543                     entry->rx_queue != rx_queue ||
1544                     entry->last_frag + 1 != frag)
1545                         continue;
1546
1547                 f_hdr = (struct ieee80211_hdr *)entry->skb_list.next->data;
1548
1549                 /*
1550                  * Check ftype and addresses are equal, else check next fragment
1551                  */
1552                 if (((hdr->frame_control ^ f_hdr->frame_control) &
1553                      cpu_to_le16(IEEE80211_FCTL_FTYPE)) ||
1554                     !ether_addr_equal(hdr->addr1, f_hdr->addr1) ||
1555                     !ether_addr_equal(hdr->addr2, f_hdr->addr2))
1556                         continue;
1557
1558                 if (time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
1559                         __skb_queue_purge(&entry->skb_list);
1560                         continue;
1561                 }
1562                 return entry;
1563         }
1564
1565         return NULL;
1566 }
1567
1568 static ieee80211_rx_result debug_noinline
1569 ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
1570 {
1571         struct ieee80211_hdr *hdr;
1572         u16 sc;
1573         __le16 fc;
1574         unsigned int frag, seq;
1575         struct ieee80211_fragment_entry *entry;
1576         struct sk_buff *skb;
1577         struct ieee80211_rx_status *status;
1578
1579         hdr = (struct ieee80211_hdr *)rx->skb->data;
1580         fc = hdr->frame_control;
1581
1582         if (ieee80211_is_ctl(fc))
1583                 return RX_CONTINUE;
1584
1585         sc = le16_to_cpu(hdr->seq_ctrl);
1586         frag = sc & IEEE80211_SCTL_FRAG;
1587
1588         if (likely((!ieee80211_has_morefrags(fc) && frag == 0) ||
1589                    is_multicast_ether_addr(hdr->addr1))) {
1590                 /* not fragmented */
1591                 goto out;
1592         }
1593         I802_DEBUG_INC(rx->local->rx_handlers_fragments);
1594
1595         if (skb_linearize(rx->skb))
1596                 return RX_DROP_UNUSABLE;
1597
1598         /*
1599          *  skb_linearize() might change the skb->data and
1600          *  previously cached variables (in this case, hdr) need to
1601          *  be refreshed with the new data.
1602          */
1603         hdr = (struct ieee80211_hdr *)rx->skb->data;
1604         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
1605
1606         if (frag == 0) {
1607                 /* This is the first fragment of a new frame. */
1608                 entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
1609                                                  rx->seqno_idx, &(rx->skb));
1610                 if (rx->key && rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP &&
1611                     ieee80211_has_protected(fc)) {
1612                         int queue = rx->security_idx;
1613                         /* Store CCMP PN so that we can verify that the next
1614                          * fragment has a sequential PN value. */
1615                         entry->ccmp = 1;
1616                         memcpy(entry->last_pn,
1617                                rx->key->u.ccmp.rx_pn[queue],
1618                                CCMP_PN_LEN);
1619                 }
1620                 return RX_QUEUED;
1621         }
1622
1623         /* This is a fragment for a frame that should already be pending in
1624          * fragment cache. Add this fragment to the end of the pending entry.
1625          */
1626         entry = ieee80211_reassemble_find(rx->sdata, frag, seq,
1627                                           rx->seqno_idx, hdr);
1628         if (!entry) {
1629                 I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1630                 return RX_DROP_MONITOR;
1631         }
1632
1633         /* Verify that MPDUs within one MSDU have sequential PN values.
1634          * (IEEE 802.11i, 8.3.3.4.5) */
1635         if (entry->ccmp) {
1636                 int i;
1637                 u8 pn[CCMP_PN_LEN], *rpn;
1638                 int queue;
1639                 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP)
1640                         return RX_DROP_UNUSABLE;
1641                 memcpy(pn, entry->last_pn, CCMP_PN_LEN);
1642                 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
1643                         pn[i]++;
1644                         if (pn[i])
1645                                 break;
1646                 }
1647                 queue = rx->security_idx;
1648                 rpn = rx->key->u.ccmp.rx_pn[queue];
1649                 if (memcmp(pn, rpn, CCMP_PN_LEN))
1650                         return RX_DROP_UNUSABLE;
1651                 memcpy(entry->last_pn, pn, CCMP_PN_LEN);
1652         }
1653
1654         skb_pull(rx->skb, ieee80211_hdrlen(fc));
1655         __skb_queue_tail(&entry->skb_list, rx->skb);
1656         entry->last_frag = frag;
1657         entry->extra_len += rx->skb->len;
1658         if (ieee80211_has_morefrags(fc)) {
1659                 rx->skb = NULL;
1660                 return RX_QUEUED;
1661         }
1662
1663         rx->skb = __skb_dequeue(&entry->skb_list);
1664         if (skb_tailroom(rx->skb) < entry->extra_len) {
1665                 I802_DEBUG_INC(rx->local->rx_expand_skb_head2);
1666                 if (unlikely(pskb_expand_head(rx->skb, 0, entry->extra_len,
1667                                               GFP_ATOMIC))) {
1668                         I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
1669                         __skb_queue_purge(&entry->skb_list);
1670                         return RX_DROP_UNUSABLE;
1671                 }
1672         }
1673         while ((skb = __skb_dequeue(&entry->skb_list))) {
1674                 memcpy(skb_put(rx->skb, skb->len), skb->data, skb->len);
1675                 dev_kfree_skb(skb);
1676         }
1677
1678         /* Complete frame has been reassembled - process it now */
1679         status = IEEE80211_SKB_RXCB(rx->skb);
1680         status->rx_flags |= IEEE80211_RX_FRAGMENTED;
1681
1682  out:
1683         if (rx->sta)
1684                 rx->sta->rx_packets++;
1685         if (is_multicast_ether_addr(hdr->addr1))
1686                 rx->local->dot11MulticastReceivedFrameCount++;
1687         else
1688                 ieee80211_led_rx(rx->local);
1689         return RX_CONTINUE;
1690 }
1691
1692 static int ieee80211_802_1x_port_control(struct ieee80211_rx_data *rx)
1693 {
1694         if (unlikely(!rx->sta || !test_sta_flag(rx->sta, WLAN_STA_AUTHORIZED)))
1695                 return -EACCES;
1696
1697         return 0;
1698 }
1699
1700 static int ieee80211_drop_unencrypted(struct ieee80211_rx_data *rx, __le16 fc)
1701 {
1702         struct sk_buff *skb = rx->skb;
1703         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1704
1705         /*
1706          * Pass through unencrypted frames if the hardware has
1707          * decrypted them already.
1708          */
1709         if (status->flag & RX_FLAG_DECRYPTED)
1710                 return 0;
1711
1712         /* Drop unencrypted frames if key is set. */
1713         if (unlikely(!ieee80211_has_protected(fc) &&
1714                      !ieee80211_is_nullfunc(fc) &&
1715                      ieee80211_is_data(fc) &&
1716                      (rx->key || rx->sdata->drop_unencrypted)))
1717                 return -EACCES;
1718
1719         return 0;
1720 }
1721
1722 static int ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
1723 {
1724         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1725         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1726         __le16 fc = hdr->frame_control;
1727
1728         /*
1729          * Pass through unencrypted frames if the hardware has
1730          * decrypted them already.
1731          */
1732         if (status->flag & RX_FLAG_DECRYPTED)
1733                 return 0;
1734
1735         if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) {
1736                 if (unlikely(!ieee80211_has_protected(fc) &&
1737                              ieee80211_is_unicast_robust_mgmt_frame(rx->skb) &&
1738                              rx->key)) {
1739                         if (ieee80211_is_deauth(fc))
1740                                 cfg80211_send_unprot_deauth(rx->sdata->dev,
1741                                                             rx->skb->data,
1742                                                             rx->skb->len);
1743                         else if (ieee80211_is_disassoc(fc))
1744                                 cfg80211_send_unprot_disassoc(rx->sdata->dev,
1745                                                               rx->skb->data,
1746                                                               rx->skb->len);
1747                         return -EACCES;
1748                 }
1749                 /* BIP does not use Protected field, so need to check MMIE */
1750                 if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
1751                              ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
1752                         if (ieee80211_is_deauth(fc))
1753                                 cfg80211_send_unprot_deauth(rx->sdata->dev,
1754                                                             rx->skb->data,
1755                                                             rx->skb->len);
1756                         else if (ieee80211_is_disassoc(fc))
1757                                 cfg80211_send_unprot_disassoc(rx->sdata->dev,
1758                                                               rx->skb->data,
1759                                                               rx->skb->len);
1760                         return -EACCES;
1761                 }
1762                 /*
1763                  * When using MFP, Action frames are not allowed prior to
1764                  * having configured keys.
1765                  */
1766                 if (unlikely(ieee80211_is_action(fc) && !rx->key &&
1767                              ieee80211_is_robust_mgmt_frame(
1768                                      (struct ieee80211_hdr *) rx->skb->data)))
1769                         return -EACCES;
1770         }
1771
1772         return 0;
1773 }
1774
1775 static int
1776 __ieee80211_data_to_8023(struct ieee80211_rx_data *rx, bool *port_control)
1777 {
1778         struct ieee80211_sub_if_data *sdata = rx->sdata;
1779         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
1780         bool check_port_control = false;
1781         struct ethhdr *ehdr;
1782         int ret;
1783
1784         *port_control = false;
1785         if (ieee80211_has_a4(hdr->frame_control) &&
1786             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && !sdata->u.vlan.sta)
1787                 return -1;
1788
1789         if (sdata->vif.type == NL80211_IFTYPE_STATION &&
1790             !!sdata->u.mgd.use_4addr != !!ieee80211_has_a4(hdr->frame_control)) {
1791
1792                 if (!sdata->u.mgd.use_4addr)
1793                         return -1;
1794                 else
1795                         check_port_control = true;
1796         }
1797
1798         if (is_multicast_ether_addr(hdr->addr1) &&
1799             sdata->vif.type == NL80211_IFTYPE_AP_VLAN && sdata->u.vlan.sta)
1800                 return -1;
1801
1802         ret = ieee80211_data_to_8023(rx->skb, sdata->vif.addr, sdata->vif.type);
1803         if (ret < 0)
1804                 return ret;
1805
1806         ehdr = (struct ethhdr *) rx->skb->data;
1807         if (ehdr->h_proto == rx->sdata->control_port_protocol)
1808                 *port_control = true;
1809         else if (check_port_control)
1810                 return -1;
1811
1812         return 0;
1813 }
1814
1815 /*
1816  * requires that rx->skb is a frame with ethernet header
1817  */
1818 static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
1819 {
1820         static const u8 pae_group_addr[ETH_ALEN] __aligned(2)
1821                 = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x03 };
1822         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1823
1824         /*
1825          * Allow EAPOL frames to us/the PAE group address regardless
1826          * of whether the frame was encrypted or not.
1827          */
1828         if (ehdr->h_proto == rx->sdata->control_port_protocol &&
1829             (ether_addr_equal(ehdr->h_dest, rx->sdata->vif.addr) ||
1830              ether_addr_equal(ehdr->h_dest, pae_group_addr)))
1831                 return true;
1832
1833         if (ieee80211_802_1x_port_control(rx) ||
1834             ieee80211_drop_unencrypted(rx, fc))
1835                 return false;
1836
1837         return true;
1838 }
1839
1840 /*
1841  * requires that rx->skb is a frame with ethernet header
1842  */
1843 static void
1844 ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
1845 {
1846         struct ieee80211_sub_if_data *sdata = rx->sdata;
1847         struct net_device *dev = sdata->dev;
1848         struct sk_buff *skb, *xmit_skb;
1849         struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
1850         struct sta_info *dsta;
1851         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1852
1853         skb = rx->skb;
1854         xmit_skb = NULL;
1855
1856         if ((sdata->vif.type == NL80211_IFTYPE_AP ||
1857              sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
1858             !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
1859             (status->rx_flags & IEEE80211_RX_RA_MATCH) &&
1860             (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
1861                 if (is_multicast_ether_addr(ehdr->h_dest)) {
1862                         /*
1863                          * send multicast frames both to higher layers in
1864                          * local net stack and back to the wireless medium
1865                          */
1866                         xmit_skb = skb_copy(skb, GFP_ATOMIC);
1867                         if (!xmit_skb)
1868                                 net_info_ratelimited("%s: failed to clone multicast frame\n",
1869                                                     dev->name);
1870                 } else {
1871                         dsta = sta_info_get(sdata, skb->data);
1872                         if (dsta) {
1873                                 /*
1874                                  * The destination station is associated to
1875                                  * this AP (in this VLAN), so send the frame
1876                                  * directly to it and do not pass it to local
1877                                  * net stack.
1878                                  */
1879                                 xmit_skb = skb;
1880                                 skb = NULL;
1881                         }
1882                 }
1883         }
1884
1885         if (skb) {
1886                 int align __maybe_unused;
1887
1888 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
1889                 /*
1890                  * 'align' will only take the values 0 or 2 here
1891                  * since all frames are required to be aligned
1892                  * to 2-byte boundaries when being passed to
1893                  * mac80211; the code here works just as well if
1894                  * that isn't true, but mac80211 assumes it can
1895                  * access fields as 2-byte aligned (e.g. for
1896                  * compare_ether_addr)
1897                  */
1898                 align = ((unsigned long)(skb->data + sizeof(struct ethhdr))) & 3;
1899                 if (align) {
1900                         if (WARN_ON(skb_headroom(skb) < 3)) {
1901                                 dev_kfree_skb(skb);
1902                                 skb = NULL;
1903                         } else {
1904                                 u8 *data = skb->data;
1905                                 size_t len = skb_headlen(skb);
1906                                 skb->data -= align;
1907                                 memmove(skb->data, data, len);
1908                                 skb_set_tail_pointer(skb, len);
1909                         }
1910                 }
1911 #endif
1912
1913                 if (skb) {
1914                         /* deliver to local stack */
1915                         skb->protocol = eth_type_trans(skb, dev);
1916                         memset(skb->cb, 0, sizeof(skb->cb));
1917                         netif_receive_skb(skb);
1918                 }
1919         }
1920
1921         if (xmit_skb) {
1922                 /*
1923                  * Send to wireless media and increase priority by 256 to
1924                  * keep the received priority instead of reclassifying
1925                  * the frame (see cfg80211_classify8021d).
1926                  */
1927                 xmit_skb->priority += 256;
1928                 xmit_skb->protocol = htons(ETH_P_802_3);
1929                 skb_reset_network_header(xmit_skb);
1930                 skb_reset_mac_header(xmit_skb);
1931                 dev_queue_xmit(xmit_skb);
1932         }
1933 }
1934
1935 static ieee80211_rx_result debug_noinline
1936 ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
1937 {
1938         struct net_device *dev = rx->sdata->dev;
1939         struct sk_buff *skb = rx->skb;
1940         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1941         __le16 fc = hdr->frame_control;
1942         struct sk_buff_head frame_list;
1943         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
1944
1945         if (unlikely(!ieee80211_is_data(fc)))
1946                 return RX_CONTINUE;
1947
1948         if (unlikely(!ieee80211_is_data_present(fc)))
1949                 return RX_DROP_MONITOR;
1950
1951         if (!(status->rx_flags & IEEE80211_RX_AMSDU))
1952                 return RX_CONTINUE;
1953
1954         if (ieee80211_has_a4(hdr->frame_control) &&
1955             rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1956             !rx->sdata->u.vlan.sta)
1957                 return RX_DROP_UNUSABLE;
1958
1959         if (is_multicast_ether_addr(hdr->addr1) &&
1960             ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1961               rx->sdata->u.vlan.sta) ||
1962              (rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
1963               rx->sdata->u.mgd.use_4addr)))
1964                 return RX_DROP_UNUSABLE;
1965
1966         skb->dev = dev;
1967         __skb_queue_head_init(&frame_list);
1968
1969         if (skb_linearize(skb))
1970                 return RX_DROP_UNUSABLE;
1971
1972         ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
1973                                  rx->sdata->vif.type,
1974                                  rx->local->hw.extra_tx_headroom, true);
1975
1976         while (!skb_queue_empty(&frame_list)) {
1977                 rx->skb = __skb_dequeue(&frame_list);
1978
1979                 if (!ieee80211_frame_allowed(rx, fc)) {
1980                         dev_kfree_skb(rx->skb);
1981                         continue;
1982                 }
1983                 dev->stats.rx_packets++;
1984                 dev->stats.rx_bytes += rx->skb->len;
1985
1986                 ieee80211_deliver_skb(rx);
1987         }
1988
1989         return RX_QUEUED;
1990 }
1991
1992 #ifdef CONFIG_MAC80211_MESH
1993 static ieee80211_rx_result
1994 ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
1995 {
1996         struct ieee80211_hdr *fwd_hdr, *hdr;
1997         struct ieee80211_tx_info *info;
1998         struct ieee80211s_hdr *mesh_hdr;
1999         struct sk_buff *skb = rx->skb, *fwd_skb;
2000         struct ieee80211_local *local = rx->local;
2001         struct ieee80211_sub_if_data *sdata = rx->sdata;
2002         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2003         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
2004         __le16 reason = cpu_to_le16(WLAN_REASON_MESH_PATH_NOFORWARD);
2005         u16 q, hdrlen;
2006
2007         hdr = (struct ieee80211_hdr *) skb->data;
2008         hdrlen = ieee80211_hdrlen(hdr->frame_control);
2009
2010         /* make sure fixed part of mesh header is there, also checks skb len */
2011         if (!pskb_may_pull(rx->skb, hdrlen + 6))
2012                 return RX_DROP_MONITOR;
2013
2014         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2015
2016         /* make sure full mesh header is there, also checks skb len */
2017         if (!pskb_may_pull(rx->skb,
2018                            hdrlen + ieee80211_get_mesh_hdrlen(mesh_hdr)))
2019                 return RX_DROP_MONITOR;
2020
2021         /* reload pointers */
2022         hdr = (struct ieee80211_hdr *) skb->data;
2023         mesh_hdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
2024
2025         /* frame is in RMC, don't forward */
2026         if (ieee80211_is_data(hdr->frame_control) &&
2027             is_multicast_ether_addr(hdr->addr1) &&
2028             mesh_rmc_check(rx->sdata, hdr->addr3, mesh_hdr))
2029                 return RX_DROP_MONITOR;
2030
2031         if (!ieee80211_is_data(hdr->frame_control) ||
2032             !(status->rx_flags & IEEE80211_RX_RA_MATCH))
2033                 return RX_CONTINUE;
2034
2035         if (!mesh_hdr->ttl)
2036                 return RX_DROP_MONITOR;
2037
2038         if (mesh_hdr->flags & MESH_FLAGS_AE) {
2039                 struct mesh_path *mppath;
2040                 char *proxied_addr;
2041                 char *mpp_addr;
2042
2043                 if (is_multicast_ether_addr(hdr->addr1)) {
2044                         mpp_addr = hdr->addr3;
2045                         proxied_addr = mesh_hdr->eaddr1;
2046                 } else if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6) {
2047                         /* has_a4 already checked in ieee80211_rx_mesh_check */
2048                         mpp_addr = hdr->addr4;
2049                         proxied_addr = mesh_hdr->eaddr2;
2050                 } else {
2051                         return RX_DROP_MONITOR;
2052                 }
2053
2054                 rcu_read_lock();
2055                 mppath = mpp_path_lookup(sdata, proxied_addr);
2056                 if (!mppath) {
2057                         mpp_path_add(sdata, proxied_addr, mpp_addr);
2058                 } else {
2059                         spin_lock_bh(&mppath->state_lock);
2060                         if (!ether_addr_equal(mppath->mpp, mpp_addr))
2061                                 memcpy(mppath->mpp, mpp_addr, ETH_ALEN);
2062                         spin_unlock_bh(&mppath->state_lock);
2063                 }
2064                 rcu_read_unlock();
2065         }
2066
2067         /* Frame has reached destination.  Don't forward */
2068         if (!is_multicast_ether_addr(hdr->addr1) &&
2069             ether_addr_equal(sdata->vif.addr, hdr->addr3))
2070                 return RX_CONTINUE;
2071
2072         q = ieee80211_select_queue_80211(sdata, skb, hdr);
2073         if (ieee80211_queue_stopped(&local->hw, q)) {
2074                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion);
2075                 return RX_DROP_MONITOR;
2076         }
2077         skb_set_queue_mapping(skb, q);
2078
2079         if (!--mesh_hdr->ttl) {
2080                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
2081                 goto out;
2082         }
2083
2084         if (!ifmsh->mshcfg.dot11MeshForwarding)
2085                 goto out;
2086
2087         fwd_skb = skb_copy(skb, GFP_ATOMIC);
2088         if (!fwd_skb) {
2089                 net_info_ratelimited("%s: failed to clone mesh frame\n",
2090                                     sdata->name);
2091                 goto out;
2092         }
2093
2094         fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
2095         fwd_hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_RETRY);
2096         info = IEEE80211_SKB_CB(fwd_skb);
2097         memset(info, 0, sizeof(*info));
2098         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
2099         info->control.vif = &rx->sdata->vif;
2100         info->control.jiffies = jiffies;
2101         if (is_multicast_ether_addr(fwd_hdr->addr1)) {
2102                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_mcast);
2103                 memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
2104                 /* update power mode indication when forwarding */
2105                 ieee80211_mps_set_frame_flags(sdata, NULL, fwd_hdr);
2106         } else if (!mesh_nexthop_lookup(sdata, fwd_skb)) {
2107                 /* mesh power mode flags updated in mesh_nexthop_lookup */
2108                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_unicast);
2109         } else {
2110                 /* unable to resolve next hop */
2111                 mesh_path_error_tx(sdata, ifmsh->mshcfg.element_ttl,
2112                                    fwd_hdr->addr3, 0, reason, fwd_hdr->addr2);
2113                 IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_no_route);
2114                 kfree_skb(fwd_skb);
2115                 return RX_DROP_MONITOR;
2116         }
2117
2118         IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, fwded_frames);
2119         ieee80211_add_pending_skb(local, fwd_skb);
2120  out:
2121         if (is_multicast_ether_addr(hdr->addr1) ||
2122             sdata->dev->flags & IFF_PROMISC)
2123                 return RX_CONTINUE;
2124         else
2125                 return RX_DROP_MONITOR;
2126 }
2127 #endif
2128
2129 static ieee80211_rx_result debug_noinline
2130 ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
2131 {
2132         struct ieee80211_sub_if_data *sdata = rx->sdata;
2133         struct ieee80211_local *local = rx->local;
2134         struct net_device *dev = sdata->dev;
2135         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
2136         __le16 fc = hdr->frame_control;
2137         bool port_control;
2138         int err;
2139
2140         if (unlikely(!ieee80211_is_data(hdr->frame_control)))
2141                 return RX_CONTINUE;
2142
2143         if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
2144                 return RX_DROP_MONITOR;
2145
2146         /*
2147          * Send unexpected-4addr-frame event to hostapd. For older versions,
2148          * also drop the frame to cooked monitor interfaces.
2149          */
2150         if (ieee80211_has_a4(hdr->frame_control) &&
2151             sdata->vif.type == NL80211_IFTYPE_AP) {
2152                 if (rx->sta &&
2153                     !test_and_set_sta_flag(rx->sta, WLAN_STA_4ADDR_EVENT))
2154                         cfg80211_rx_unexpected_4addr_frame(
2155                                 rx->sdata->dev, rx->sta->sta.addr, GFP_ATOMIC);
2156                 return RX_DROP_MONITOR;
2157         }
2158
2159         err = __ieee80211_data_to_8023(rx, &port_control);
2160         if (unlikely(err))
2161                 return RX_DROP_UNUSABLE;
2162
2163         if (!ieee80211_frame_allowed(rx, fc))
2164                 return RX_DROP_MONITOR;
2165
2166         if (rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
2167             unlikely(port_control) && sdata->bss) {
2168                 sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
2169                                      u.ap);
2170                 dev = sdata->dev;
2171                 rx->sdata = sdata;
2172         }
2173
2174         rx->skb->dev = dev;
2175
2176         dev->stats.rx_packets++;
2177         dev->stats.rx_bytes += rx->skb->len;
2178
2179         if (local->ps_sdata && local->hw.conf.dynamic_ps_timeout > 0 &&
2180             !is_multicast_ether_addr(
2181                     ((struct ethhdr *)rx->skb->data)->h_dest) &&
2182             (!local->scanning &&
2183              !test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state))) {
2184                         mod_timer(&local->dynamic_ps_timer, jiffies +
2185                          msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
2186         }
2187
2188         ieee80211_deliver_skb(rx);
2189
2190         return RX_QUEUED;
2191 }
2192
2193 static ieee80211_rx_result debug_noinline
2194 ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
2195 {
2196         struct sk_buff *skb = rx->skb;
2197         struct ieee80211_bar *bar = (struct ieee80211_bar *)skb->data;
2198         struct tid_ampdu_rx *tid_agg_rx;
2199         u16 start_seq_num;
2200         u16 tid;
2201
2202         if (likely(!ieee80211_is_ctl(bar->frame_control)))
2203                 return RX_CONTINUE;
2204
2205         if (ieee80211_is_back_req(bar->frame_control)) {
2206                 struct {
2207                         __le16 control, start_seq_num;
2208                 } __packed bar_data;
2209
2210                 if (!rx->sta)
2211                         return RX_DROP_MONITOR;
2212
2213                 if (skb_copy_bits(skb, offsetof(struct ieee80211_bar, control),
2214                                   &bar_data, sizeof(bar_data)))
2215                         return RX_DROP_MONITOR;
2216
2217                 tid = le16_to_cpu(bar_data.control) >> 12;
2218
2219                 tid_agg_rx = rcu_dereference(rx->sta->ampdu_mlme.tid_rx[tid]);
2220                 if (!tid_agg_rx)
2221                         return RX_DROP_MONITOR;
2222
2223                 start_seq_num = le16_to_cpu(bar_data.start_seq_num) >> 4;
2224
2225                 /* reset session timer */
2226                 if (tid_agg_rx->timeout)
2227                         mod_timer(&tid_agg_rx->session_timer,
2228                                   TU_TO_EXP_TIME(tid_agg_rx->timeout));
2229
2230                 spin_lock(&tid_agg_rx->reorder_lock);
2231                 /* release stored frames up to start of BAR */
2232                 ieee80211_release_reorder_frames(rx->sdata, tid_agg_rx,
2233                                                  start_seq_num, frames);
2234                 spin_unlock(&tid_agg_rx->reorder_lock);
2235
2236                 kfree_skb(skb);
2237                 return RX_QUEUED;
2238         }
2239
2240         /*
2241          * After this point, we only want management frames,
2242          * so we can drop all remaining control frames to
2243          * cooked monitor interfaces.
2244          */
2245         return RX_DROP_MONITOR;
2246 }
2247
2248 static void ieee80211_process_sa_query_req(struct ieee80211_sub_if_data *sdata,
2249                                            struct ieee80211_mgmt *mgmt,
2250                                            size_t len)
2251 {
2252         struct ieee80211_local *local = sdata->local;
2253         struct sk_buff *skb;
2254         struct ieee80211_mgmt *resp;
2255
2256         if (!ether_addr_equal(mgmt->da, sdata->vif.addr)) {
2257                 /* Not to own unicast address */
2258                 return;
2259         }
2260
2261         if (!ether_addr_equal(mgmt->sa, sdata->u.mgd.bssid) ||
2262             !ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid)) {
2263                 /* Not from the current AP or not associated yet. */
2264                 return;
2265         }
2266
2267         if (len < 24 + 1 + sizeof(resp->u.action.u.sa_query)) {
2268                 /* Too short SA Query request frame */
2269                 return;
2270         }
2271
2272         skb = dev_alloc_skb(sizeof(*resp) + local->hw.extra_tx_headroom);
2273         if (skb == NULL)
2274                 return;
2275
2276         skb_reserve(skb, local->hw.extra_tx_headroom);
2277         resp = (struct ieee80211_mgmt *) skb_put(skb, 24);
2278         memset(resp, 0, 24);
2279         memcpy(resp->da, mgmt->sa, ETH_ALEN);
2280         memcpy(resp->sa, sdata->vif.addr, ETH_ALEN);
2281         memcpy(resp->bssid, sdata->u.mgd.bssid, ETH_ALEN);
2282         resp->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2283                                           IEEE80211_STYPE_ACTION);
2284         skb_put(skb, 1 + sizeof(resp->u.action.u.sa_query));
2285         resp->u.action.category = WLAN_CATEGORY_SA_QUERY;
2286         resp->u.action.u.sa_query.action = WLAN_ACTION_SA_QUERY_RESPONSE;
2287         memcpy(resp->u.action.u.sa_query.trans_id,
2288                mgmt->u.action.u.sa_query.trans_id,
2289                WLAN_SA_QUERY_TR_ID_LEN);
2290
2291         ieee80211_tx_skb(sdata, skb);
2292 }
2293
2294 static ieee80211_rx_result debug_noinline
2295 ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
2296 {
2297         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2298         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2299
2300         /*
2301          * From here on, look only at management frames.
2302          * Data and control frames are already handled,
2303          * and unknown (reserved) frames are useless.
2304          */
2305         if (rx->skb->len < 24)
2306                 return RX_DROP_MONITOR;
2307
2308         if (!ieee80211_is_mgmt(mgmt->frame_control))
2309                 return RX_DROP_MONITOR;
2310
2311         if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
2312             ieee80211_is_beacon(mgmt->frame_control) &&
2313             !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) {
2314                 int sig = 0;
2315
2316                 if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2317                         sig = status->signal;
2318
2319                 cfg80211_report_obss_beacon(rx->local->hw.wiphy,
2320                                             rx->skb->data, rx->skb->len,
2321                                             status->freq, sig);
2322                 rx->flags |= IEEE80211_RX_BEACON_REPORTED;
2323         }
2324
2325         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2326                 return RX_DROP_MONITOR;
2327
2328         if (ieee80211_drop_unencrypted_mgmt(rx))
2329                 return RX_DROP_UNUSABLE;
2330
2331         return RX_CONTINUE;
2332 }
2333
2334 static ieee80211_rx_result debug_noinline
2335 ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
2336 {
2337         struct ieee80211_local *local = rx->local;
2338         struct ieee80211_sub_if_data *sdata = rx->sdata;
2339         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2340         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2341         int len = rx->skb->len;
2342
2343         if (!ieee80211_is_action(mgmt->frame_control))
2344                 return RX_CONTINUE;
2345
2346         /* drop too small frames */
2347         if (len < IEEE80211_MIN_ACTION_SIZE)
2348                 return RX_DROP_UNUSABLE;
2349
2350         if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC &&
2351             mgmt->u.action.category != WLAN_CATEGORY_SELF_PROTECTED)
2352                 return RX_DROP_UNUSABLE;
2353
2354         if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
2355                 return RX_DROP_UNUSABLE;
2356
2357         switch (mgmt->u.action.category) {
2358         case WLAN_CATEGORY_HT:
2359                 /* reject HT action frames from stations not supporting HT */
2360                 if (!rx->sta->sta.ht_cap.ht_supported)
2361                         goto invalid;
2362
2363                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2364                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2365                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2366                     sdata->vif.type != NL80211_IFTYPE_AP &&
2367                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2368                         break;
2369
2370                 /* verify action & smps_control/chanwidth are present */
2371                 if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2372                         goto invalid;
2373
2374                 switch (mgmt->u.action.u.ht_smps.action) {
2375                 case WLAN_HT_ACTION_SMPS: {
2376                         struct ieee80211_supported_band *sband;
2377                         enum ieee80211_smps_mode smps_mode;
2378
2379                         /* convert to HT capability */
2380                         switch (mgmt->u.action.u.ht_smps.smps_control) {
2381                         case WLAN_HT_SMPS_CONTROL_DISABLED:
2382                                 smps_mode = IEEE80211_SMPS_OFF;
2383                                 break;
2384                         case WLAN_HT_SMPS_CONTROL_STATIC:
2385                                 smps_mode = IEEE80211_SMPS_STATIC;
2386                                 break;
2387                         case WLAN_HT_SMPS_CONTROL_DYNAMIC:
2388                                 smps_mode = IEEE80211_SMPS_DYNAMIC;
2389                                 break;
2390                         default:
2391                                 goto invalid;
2392                         }
2393
2394                         /* if no change do nothing */
2395                         if (rx->sta->sta.smps_mode == smps_mode)
2396                                 goto handled;
2397                         rx->sta->sta.smps_mode = smps_mode;
2398
2399                         sband = rx->local->hw.wiphy->bands[status->band];
2400
2401                         rate_control_rate_update(local, sband, rx->sta,
2402                                                  IEEE80211_RC_SMPS_CHANGED);
2403                         goto handled;
2404                 }
2405                 case WLAN_HT_ACTION_NOTIFY_CHANWIDTH: {
2406                         struct ieee80211_supported_band *sband;
2407                         u8 chanwidth = mgmt->u.action.u.ht_notify_cw.chanwidth;
2408                         enum ieee80211_sta_rx_bandwidth new_bw;
2409
2410                         /* If it doesn't support 40 MHz it can't change ... */
2411                         if (!(rx->sta->sta.ht_cap.cap &
2412                                         IEEE80211_HT_CAP_SUP_WIDTH_20_40))
2413                                 goto handled;
2414
2415                         if (chanwidth == IEEE80211_HT_CHANWIDTH_20MHZ)
2416                                 new_bw = IEEE80211_STA_RX_BW_20;
2417                         else
2418                                 new_bw = ieee80211_sta_cur_vht_bw(rx->sta);
2419
2420                         if (rx->sta->sta.bandwidth == new_bw)
2421                                 goto handled;
2422
2423                         sband = rx->local->hw.wiphy->bands[status->band];
2424
2425                         rate_control_rate_update(local, sband, rx->sta,
2426                                                  IEEE80211_RC_BW_CHANGED);
2427                         goto handled;
2428                 }
2429                 default:
2430                         goto invalid;
2431                 }
2432
2433                 break;
2434         case WLAN_CATEGORY_PUBLIC:
2435                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2436                         goto invalid;
2437                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2438                         break;
2439                 if (!rx->sta)
2440                         break;
2441                 if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
2442                         break;
2443                 if (mgmt->u.action.u.ext_chan_switch.action_code !=
2444                                 WLAN_PUB_ACTION_EXT_CHANSW_ANN)
2445                         break;
2446                 if (len < offsetof(struct ieee80211_mgmt,
2447                                    u.action.u.ext_chan_switch.variable))
2448                         goto invalid;
2449                 goto queue;
2450         case WLAN_CATEGORY_VHT:
2451                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2452                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2453                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2454                     sdata->vif.type != NL80211_IFTYPE_AP &&
2455                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2456                         break;
2457
2458                 /* verify action code is present */
2459                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2460                         goto invalid;
2461
2462                 switch (mgmt->u.action.u.vht_opmode_notif.action_code) {
2463                 case WLAN_VHT_ACTION_OPMODE_NOTIF: {
2464                         u8 opmode;
2465
2466                         /* verify opmode is present */
2467                         if (len < IEEE80211_MIN_ACTION_SIZE + 2)
2468                                 goto invalid;
2469
2470                         opmode = mgmt->u.action.u.vht_opmode_notif.operating_mode;
2471
2472                         ieee80211_vht_handle_opmode(rx->sdata, rx->sta,
2473                                                     opmode, status->band,
2474                                                     false);
2475                         goto handled;
2476                 }
2477                 default:
2478                         break;
2479                 }
2480                 break;
2481         case WLAN_CATEGORY_BACK:
2482                 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
2483                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
2484                     sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
2485                     sdata->vif.type != NL80211_IFTYPE_AP &&
2486                     sdata->vif.type != NL80211_IFTYPE_ADHOC)
2487                         break;
2488
2489                 /* verify action_code is present */
2490                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2491                         break;
2492
2493                 switch (mgmt->u.action.u.addba_req.action_code) {
2494                 case WLAN_ACTION_ADDBA_REQ:
2495                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2496                                    sizeof(mgmt->u.action.u.addba_req)))
2497                                 goto invalid;
2498                         break;
2499                 case WLAN_ACTION_ADDBA_RESP:
2500                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2501                                    sizeof(mgmt->u.action.u.addba_resp)))
2502                                 goto invalid;
2503                         break;
2504                 case WLAN_ACTION_DELBA:
2505                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2506                                    sizeof(mgmt->u.action.u.delba)))
2507                                 goto invalid;
2508                         break;
2509                 default:
2510                         goto invalid;
2511                 }
2512
2513                 goto queue;
2514         case WLAN_CATEGORY_SPECTRUM_MGMT:
2515                 if (status->band != IEEE80211_BAND_5GHZ)
2516                         break;
2517
2518                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2519                         break;
2520
2521                 /* verify action_code is present */
2522                 if (len < IEEE80211_MIN_ACTION_SIZE + 1)
2523                         break;
2524
2525                 switch (mgmt->u.action.u.measurement.action_code) {
2526                 case WLAN_ACTION_SPCT_MSR_REQ:
2527                         if (len < (IEEE80211_MIN_ACTION_SIZE +
2528                                    sizeof(mgmt->u.action.u.measurement)))
2529                                 break;
2530                         ieee80211_process_measurement_req(sdata, mgmt, len);
2531                         goto handled;
2532                 case WLAN_ACTION_SPCT_CHL_SWITCH:
2533                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2534                                 break;
2535
2536                         if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
2537                                 break;
2538
2539                         goto queue;
2540                 }
2541                 break;
2542         case WLAN_CATEGORY_SA_QUERY:
2543                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2544                            sizeof(mgmt->u.action.u.sa_query)))
2545                         break;
2546
2547                 switch (mgmt->u.action.u.sa_query.action) {
2548                 case WLAN_ACTION_SA_QUERY_REQUEST:
2549                         if (sdata->vif.type != NL80211_IFTYPE_STATION)
2550                                 break;
2551                         ieee80211_process_sa_query_req(sdata, mgmt, len);
2552                         goto handled;
2553                 }
2554                 break;
2555         case WLAN_CATEGORY_SELF_PROTECTED:
2556                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2557                            sizeof(mgmt->u.action.u.self_prot.action_code)))
2558                         break;
2559
2560                 switch (mgmt->u.action.u.self_prot.action_code) {
2561                 case WLAN_SP_MESH_PEERING_OPEN:
2562                 case WLAN_SP_MESH_PEERING_CLOSE:
2563                 case WLAN_SP_MESH_PEERING_CONFIRM:
2564                         if (!ieee80211_vif_is_mesh(&sdata->vif))
2565                                 goto invalid;
2566                         if (sdata->u.mesh.user_mpm)
2567                                 /* userspace handles this frame */
2568                                 break;
2569                         goto queue;
2570                 case WLAN_SP_MGK_INFORM:
2571                 case WLAN_SP_MGK_ACK:
2572                         if (!ieee80211_vif_is_mesh(&sdata->vif))
2573                                 goto invalid;
2574                         break;
2575                 }
2576                 break;
2577         case WLAN_CATEGORY_MESH_ACTION:
2578                 if (len < (IEEE80211_MIN_ACTION_SIZE +
2579                            sizeof(mgmt->u.action.u.mesh_action.action_code)))
2580                         break;
2581
2582                 if (!ieee80211_vif_is_mesh(&sdata->vif))
2583                         break;
2584                 if (mesh_action_is_path_sel(mgmt) &&
2585                     !mesh_path_sel_is_hwmp(sdata))
2586                         break;
2587                 goto queue;
2588         }
2589
2590         return RX_CONTINUE;
2591
2592  invalid:
2593         status->rx_flags |= IEEE80211_RX_MALFORMED_ACTION_FRM;
2594         /* will return in the next handlers */
2595         return RX_CONTINUE;
2596
2597  handled:
2598         if (rx->sta)
2599                 rx->sta->rx_packets++;
2600         dev_kfree_skb(rx->skb);
2601         return RX_QUEUED;
2602
2603  queue:
2604         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2605         skb_queue_tail(&sdata->skb_queue, rx->skb);
2606         ieee80211_queue_work(&local->hw, &sdata->work);
2607         if (rx->sta)
2608                 rx->sta->rx_packets++;
2609         return RX_QUEUED;
2610 }
2611
2612 static ieee80211_rx_result debug_noinline
2613 ieee80211_rx_h_userspace_mgmt(struct ieee80211_rx_data *rx)
2614 {
2615         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2616         int sig = 0;
2617
2618         /* skip known-bad action frames and return them in the next handler */
2619         if (status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM)
2620                 return RX_CONTINUE;
2621
2622         /*
2623          * Getting here means the kernel doesn't know how to handle
2624          * it, but maybe userspace does ... include returned frames
2625          * so userspace can register for those to know whether ones
2626          * it transmitted were processed or returned.
2627          */
2628
2629         if (rx->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
2630                 sig = status->signal;
2631
2632         if (cfg80211_rx_mgmt(&rx->sdata->wdev, status->freq, sig,
2633                              rx->skb->data, rx->skb->len,
2634                              GFP_ATOMIC)) {
2635                 if (rx->sta)
2636                         rx->sta->rx_packets++;
2637                 dev_kfree_skb(rx->skb);
2638                 return RX_QUEUED;
2639         }
2640
2641         return RX_CONTINUE;
2642 }
2643
2644 static ieee80211_rx_result debug_noinline
2645 ieee80211_rx_h_action_return(struct ieee80211_rx_data *rx)
2646 {
2647         struct ieee80211_local *local = rx->local;
2648         struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
2649         struct sk_buff *nskb;
2650         struct ieee80211_sub_if_data *sdata = rx->sdata;
2651         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
2652
2653         if (!ieee80211_is_action(mgmt->frame_control))
2654                 return RX_CONTINUE;
2655
2656         /*
2657          * For AP mode, hostapd is responsible for handling any action
2658          * frames that we didn't handle, including returning unknown
2659          * ones. For all other modes we will return them to the sender,
2660          * setting the 0x80 bit in the action category, as required by
2661          * 802.11-2012 9.24.4.
2662          * Newer versions of hostapd shall also use the management frame
2663          * registration mechanisms, but older ones still use cooked
2664          * monitor interfaces so push all frames there.
2665          */
2666         if (!(status->rx_flags & IEEE80211_RX_MALFORMED_ACTION_FRM) &&
2667             (sdata->vif.type == NL80211_IFTYPE_AP ||
2668              sdata->vif.type == NL80211_IFTYPE_AP_VLAN))
2669                 return RX_DROP_MONITOR;
2670
2671         if (is_multicast_ether_addr(mgmt->da))
2672                 return RX_DROP_MONITOR;
2673
2674         /* do not return rejected action frames */
2675         if (mgmt->u.action.category & 0x80)
2676                 return RX_DROP_UNUSABLE;
2677
2678         nskb = skb_copy_expand(rx->skb, local->hw.extra_tx_headroom, 0,
2679                                GFP_ATOMIC);
2680         if (nskb) {
2681                 struct ieee80211_mgmt *nmgmt = (void *)nskb->data;
2682
2683                 nmgmt->u.action.category |= 0x80;
2684                 memcpy(nmgmt->da, nmgmt->sa, ETH_ALEN);
2685                 memcpy(nmgmt->sa, rx->sdata->vif.addr, ETH_ALEN);
2686
2687                 memset(nskb->cb, 0, sizeof(nskb->cb));
2688
2689                 if (rx->sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE) {
2690                         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(nskb);
2691
2692                         info->flags = IEEE80211_TX_CTL_TX_OFFCHAN |
2693                                       IEEE80211_TX_INTFL_OFFCHAN_TX_OK |
2694                                       IEEE80211_TX_CTL_NO_CCK_RATE;
2695                         if (local->hw.flags & IEEE80211_HW_QUEUE_CONTROL)
2696                                 info->hw_queue =
2697                                         local->hw.offchannel_tx_hw_queue;
2698                 }
2699
2700                 __ieee80211_tx_skb_tid_band(rx->sdata, nskb, 7,
2701                                             status->band);
2702         }
2703         dev_kfree_skb(rx->skb);
2704         return RX_QUEUED;
2705 }
2706
2707 static ieee80211_rx_result debug_noinline
2708 ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
2709 {
2710         struct ieee80211_sub_if_data *sdata = rx->sdata;
2711         struct ieee80211_mgmt *mgmt = (void *)rx->skb->data;
2712         __le16 stype;
2713
2714         stype = mgmt->frame_control & cpu_to_le16(IEEE80211_FCTL_STYPE);
2715
2716         if (!ieee80211_vif_is_mesh(&sdata->vif) &&
2717             sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2718             sdata->vif.type != NL80211_IFTYPE_STATION)
2719                 return RX_DROP_MONITOR;
2720
2721         switch (stype) {
2722         case cpu_to_le16(IEEE80211_STYPE_AUTH):
2723         case cpu_to_le16(IEEE80211_STYPE_BEACON):
2724         case cpu_to_le16(IEEE80211_STYPE_PROBE_RESP):
2725                 /* process for all: mesh, mlme, ibss */
2726                 break;
2727         case cpu_to_le16(IEEE80211_STYPE_ASSOC_RESP):
2728         case cpu_to_le16(IEEE80211_STYPE_REASSOC_RESP):
2729         case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
2730         case cpu_to_le16(IEEE80211_STYPE_DISASSOC):
2731                 if (is_multicast_ether_addr(mgmt->da) &&
2732                     !is_broadcast_ether_addr(mgmt->da))
2733                         return RX_DROP_MONITOR;
2734
2735                 /* process only for station */
2736                 if (sdata->vif.type != NL80211_IFTYPE_STATION)
2737                         return RX_DROP_MONITOR;
2738                 break;
2739         case cpu_to_le16(IEEE80211_STYPE_PROBE_REQ):
2740                 /* process only for ibss and mesh */
2741                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC &&
2742                     sdata->vif.type != NL80211_IFTYPE_MESH_POINT)
2743                         return RX_DROP_MONITOR;
2744                 break;
2745         default:
2746                 return RX_DROP_MONITOR;
2747         }
2748
2749         /* queue up frame and kick off work to process it */
2750         rx->skb->pkt_type = IEEE80211_SDATA_QUEUE_TYPE_FRAME;
2751         skb_queue_tail(&sdata->skb_queue, rx->skb);
2752         ieee80211_queue_work(&rx->local->hw, &sdata->work);
2753         if (rx->sta)
2754                 rx->sta->rx_packets++;
2755
2756         return RX_QUEUED;
2757 }
2758
2759 /* TODO: use IEEE80211_RX_FRAGMENTED */
2760 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
2761                                         struct ieee80211_rate *rate)
2762 {
2763         struct ieee80211_sub_if_data *sdata;
2764         struct ieee80211_local *local = rx->local;
2765         struct sk_buff *skb = rx->skb, *skb2;
2766         struct net_device *prev_dev = NULL;
2767         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2768         int needed_headroom;
2769
2770         /*
2771          * If cooked monitor has been processed already, then
2772          * don't do it again. If not, set the flag.
2773          */
2774         if (rx->flags & IEEE80211_RX_CMNTR)
2775                 goto out_free_skb;
2776         rx->flags |= IEEE80211_RX_CMNTR;
2777
2778         /* If there are no cooked monitor interfaces, just free the SKB */
2779         if (!local->cooked_mntrs)
2780                 goto out_free_skb;
2781
2782         /* room for the radiotap header based on driver features */
2783         needed_headroom = ieee80211_rx_radiotap_space(local, status);
2784
2785         if (skb_headroom(skb) < needed_headroom &&
2786             pskb_expand_head(skb, needed_headroom, 0, GFP_ATOMIC))
2787                 goto out_free_skb;
2788
2789         /* prepend radiotap information */
2790         ieee80211_add_rx_radiotap_header(local, skb, rate, needed_headroom,
2791                                          false);
2792
2793         skb_set_mac_header(skb, 0);
2794         skb->ip_summed = CHECKSUM_UNNECESSARY;
2795         skb->pkt_type = PACKET_OTHERHOST;
2796         skb->protocol = htons(ETH_P_802_2);
2797
2798         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
2799                 if (!ieee80211_sdata_running(sdata))
2800                         continue;
2801
2802                 if (sdata->vif.type != NL80211_IFTYPE_MONITOR ||
2803                     !(sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES))
2804                         continue;
2805
2806                 if (prev_dev) {
2807                         skb2 = skb_clone(skb, GFP_ATOMIC);
2808                         if (skb2) {
2809                                 skb2->dev = prev_dev;
2810                                 netif_receive_skb(skb2);
2811                         }
2812                 }
2813
2814                 prev_dev = sdata->dev;
2815                 sdata->dev->stats.rx_packets++;
2816                 sdata->dev->stats.rx_bytes += skb->len;
2817         }
2818
2819         if (prev_dev) {
2820                 skb->dev = prev_dev;
2821                 netif_receive_skb(skb);
2822                 return;
2823         }
2824
2825  out_free_skb:
2826         dev_kfree_skb(skb);
2827 }
2828
2829 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
2830                                          ieee80211_rx_result res)
2831 {
2832         switch (res) {
2833         case RX_DROP_MONITOR:
2834                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2835                 if (rx->sta)
2836                         rx->sta->rx_dropped++;
2837                 /* fall through */
2838         case RX_CONTINUE: {
2839                 struct ieee80211_rate *rate = NULL;
2840                 struct ieee80211_supported_band *sband;
2841                 struct ieee80211_rx_status *status;
2842
2843                 status = IEEE80211_SKB_RXCB((rx->skb));
2844
2845                 sband = rx->local->hw.wiphy->bands[status->band];
2846                 if (!(status->flag & RX_FLAG_HT) &&
2847                     !(status->flag & RX_FLAG_VHT))
2848                         rate = &sband->bitrates[status->rate_idx];
2849
2850                 ieee80211_rx_cooked_monitor(rx, rate);
2851                 break;
2852                 }
2853         case RX_DROP_UNUSABLE:
2854                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
2855                 if (rx->sta)
2856                         rx->sta->rx_dropped++;
2857                 dev_kfree_skb(rx->skb);
2858                 break;
2859         case RX_QUEUED:
2860                 I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
2861                 break;
2862         }
2863 }
2864
2865 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
2866                                   struct sk_buff_head *frames)
2867 {
2868         ieee80211_rx_result res = RX_DROP_MONITOR;
2869         struct sk_buff *skb;
2870
2871 #define CALL_RXH(rxh)                   \
2872         do {                            \
2873                 res = rxh(rx);          \
2874                 if (res != RX_CONTINUE) \
2875                         goto rxh_next;  \
2876         } while (0);
2877
2878         spin_lock_bh(&rx->local->rx_path_lock);
2879
2880         while ((skb = __skb_dequeue(frames))) {
2881                 /*
2882                  * all the other fields are valid across frames
2883                  * that belong to an aMPDU since they are on the
2884                  * same TID from the same station
2885                  */
2886                 rx->skb = skb;
2887
2888                 CALL_RXH(ieee80211_rx_h_decrypt)
2889                 CALL_RXH(ieee80211_rx_h_check_more_data)
2890                 CALL_RXH(ieee80211_rx_h_uapsd_and_pspoll)
2891                 CALL_RXH(ieee80211_rx_h_sta_process)
2892                 CALL_RXH(ieee80211_rx_h_defragment)
2893                 CALL_RXH(ieee80211_rx_h_michael_mic_verify)
2894                 /* must be after MMIC verify so header is counted in MPDU mic */
2895 #ifdef CONFIG_MAC80211_MESH
2896                 if (ieee80211_vif_is_mesh(&rx->sdata->vif))
2897                         CALL_RXH(ieee80211_rx_h_mesh_fwding);
2898 #endif
2899                 CALL_RXH(ieee80211_rx_h_amsdu)
2900                 CALL_RXH(ieee80211_rx_h_data)
2901
2902                 /* special treatment -- needs the queue */
2903                 res = ieee80211_rx_h_ctrl(rx, frames);
2904                 if (res != RX_CONTINUE)
2905                         goto rxh_next;
2906
2907                 CALL_RXH(ieee80211_rx_h_mgmt_check)
2908                 CALL_RXH(ieee80211_rx_h_action)
2909                 CALL_RXH(ieee80211_rx_h_userspace_mgmt)
2910                 CALL_RXH(ieee80211_rx_h_action_return)
2911                 CALL_RXH(ieee80211_rx_h_mgmt)
2912
2913  rxh_next:
2914                 ieee80211_rx_handlers_result(rx, res);
2915
2916 #undef CALL_RXH
2917         }
2918
2919         spin_unlock_bh(&rx->local->rx_path_lock);
2920 }
2921
2922 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
2923 {
2924         struct sk_buff_head reorder_release;
2925         ieee80211_rx_result res = RX_DROP_MONITOR;
2926
2927         __skb_queue_head_init(&reorder_release);
2928
2929 #define CALL_RXH(rxh)                   \
2930         do {                            \
2931                 res = rxh(rx);          \
2932                 if (res != RX_CONTINUE) \
2933                         goto rxh_next;  \
2934         } while (0);
2935
2936         CALL_RXH(ieee80211_rx_h_check)
2937
2938         ieee80211_rx_reorder_ampdu(rx, &reorder_release);
2939
2940         ieee80211_rx_handlers(rx, &reorder_release);
2941         return;
2942
2943  rxh_next:
2944         ieee80211_rx_handlers_result(rx, res);
2945
2946 #undef CALL_RXH
2947 }
2948
2949 /*
2950  * This function makes calls into the RX path, therefore
2951  * it has to be invoked under RCU read lock.
2952  */
2953 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
2954 {
2955         struct sk_buff_head frames;
2956         struct ieee80211_rx_data rx = {
2957                 .sta = sta,
2958                 .sdata = sta->sdata,
2959                 .local = sta->local,
2960                 /* This is OK -- must be QoS data frame */
2961                 .security_idx = tid,
2962                 .seqno_idx = tid,
2963                 .flags = 0,
2964         };
2965         struct tid_ampdu_rx *tid_agg_rx;
2966
2967         tid_agg_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
2968         if (!tid_agg_rx)
2969                 return;
2970
2971         __skb_queue_head_init(&frames);
2972
2973         spin_lock(&tid_agg_rx->reorder_lock);
2974         ieee80211_sta_reorder_release(sta->sdata, tid_agg_rx, &frames);
2975         spin_unlock(&tid_agg_rx->reorder_lock);
2976
2977         ieee80211_rx_handlers(&rx, &frames);
2978 }
2979
2980 /* main receive path */
2981
2982 static int prepare_for_handlers(struct ieee80211_rx_data *rx,
2983                                 struct ieee80211_hdr *hdr)
2984 {
2985         struct ieee80211_sub_if_data *sdata = rx->sdata;
2986         struct sk_buff *skb = rx->skb;
2987         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
2988         u8 *bssid = ieee80211_get_bssid(hdr, skb->len, sdata->vif.type);
2989         int multicast = is_multicast_ether_addr(hdr->addr1);
2990
2991         switch (sdata->vif.type) {
2992         case NL80211_IFTYPE_STATION:
2993                 if (!bssid && !sdata->u.mgd.use_4addr)
2994                         return 0;
2995                 if (!multicast &&
2996                     !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
2997                         if (!(sdata->dev->flags & IFF_PROMISC) ||
2998                             sdata->u.mgd.use_4addr)
2999                                 return 0;
3000                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3001                 }
3002                 break;
3003         case NL80211_IFTYPE_ADHOC:
3004                 if (!bssid)
3005                         return 0;
3006                 if (ether_addr_equal(sdata->vif.addr, hdr->addr2) ||
3007                     ether_addr_equal(sdata->u.ibss.bssid, hdr->addr2))
3008                         return 0;
3009                 if (ieee80211_is_beacon(hdr->frame_control)) {
3010                         return 1;
3011                 } else if (!ieee80211_bssid_match(bssid, sdata->u.ibss.bssid)) {
3012                         return 0;
3013                 } else if (!multicast &&
3014                            !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
3015                         if (!(sdata->dev->flags & IFF_PROMISC))
3016                                 return 0;
3017                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3018                 } else if (!rx->sta) {
3019                         int rate_idx;
3020                         if (status->flag & (RX_FLAG_HT | RX_FLAG_VHT))
3021                                 rate_idx = 0; /* TODO: HT/VHT rates */
3022                         else
3023                                 rate_idx = status->rate_idx;
3024                         ieee80211_ibss_rx_no_sta(sdata, bssid, hdr->addr2,
3025                                                  BIT(rate_idx));
3026                 }
3027                 break;
3028         case NL80211_IFTYPE_MESH_POINT:
3029                 if (!multicast &&
3030                     !ether_addr_equal(sdata->vif.addr, hdr->addr1)) {
3031                         if (!(sdata->dev->flags & IFF_PROMISC))
3032                                 return 0;
3033
3034                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3035                 }
3036                 break;
3037         case NL80211_IFTYPE_AP_VLAN:
3038         case NL80211_IFTYPE_AP:
3039                 if (!bssid) {
3040                         if (!ether_addr_equal(sdata->vif.addr, hdr->addr1))
3041                                 return 0;
3042                 } else if (!ieee80211_bssid_match(bssid, sdata->vif.addr)) {
3043                         /*
3044                          * Accept public action frames even when the
3045                          * BSSID doesn't match, this is used for P2P
3046                          * and location updates. Note that mac80211
3047                          * itself never looks at these frames.
3048                          */
3049                         if (!multicast &&
3050                             !ether_addr_equal(sdata->vif.addr, hdr->addr1))
3051                                 return 0;
3052                         if (ieee80211_is_public_action(hdr, skb->len))
3053                                 return 1;
3054                         if (!ieee80211_is_beacon(hdr->frame_control))
3055                                 return 0;
3056                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3057                 }
3058                 break;
3059         case NL80211_IFTYPE_WDS:
3060                 if (bssid || !ieee80211_is_data(hdr->frame_control))
3061                         return 0;
3062                 if (!ether_addr_equal(sdata->u.wds.remote_addr, hdr->addr2))
3063                         return 0;
3064                 break;
3065         case NL80211_IFTYPE_P2P_DEVICE:
3066                 if (!ieee80211_is_public_action(hdr, skb->len) &&
3067                     !ieee80211_is_probe_req(hdr->frame_control) &&
3068                     !ieee80211_is_probe_resp(hdr->frame_control) &&
3069                     !ieee80211_is_beacon(hdr->frame_control))
3070                         return 0;
3071                 if (!ether_addr_equal(sdata->vif.addr, hdr->addr1) &&
3072                     !multicast)
3073                         status->rx_flags &= ~IEEE80211_RX_RA_MATCH;
3074                 break;
3075         default:
3076                 /* should never get here */
3077                 WARN_ON_ONCE(1);
3078                 break;
3079         }
3080
3081         return 1;
3082 }
3083
3084 /*
3085  * This function returns whether or not the SKB
3086  * was destined for RX processing or not, which,
3087  * if consume is true, is equivalent to whether
3088  * or not the skb was consumed.
3089  */
3090 static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx,
3091                                             struct sk_buff *skb, bool consume)
3092 {
3093         struct ieee80211_local *local = rx->local;
3094         struct ieee80211_sub_if_data *sdata = rx->sdata;
3095         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3096         struct ieee80211_hdr *hdr = (void *)skb->data;
3097         int prepares;
3098
3099         rx->skb = skb;
3100         status->rx_flags |= IEEE80211_RX_RA_MATCH;
3101         prepares = prepare_for_handlers(rx, hdr);
3102
3103         if (!prepares)
3104                 return false;
3105
3106         if (!consume) {
3107                 skb = skb_copy(skb, GFP_ATOMIC);
3108                 if (!skb) {
3109                         if (net_ratelimit())
3110                                 wiphy_debug(local->hw.wiphy,
3111                                         "failed to copy skb for %s\n",
3112                                         sdata->name);
3113                         return true;
3114                 }
3115
3116                 rx->skb = skb;
3117         }
3118
3119         ieee80211_invoke_rx_handlers(rx);
3120         return true;
3121 }
3122
3123 /*
3124  * This is the actual Rx frames handler. as it blongs to Rx path it must
3125  * be called with rcu_read_lock protection.
3126  */
3127 static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw,
3128                                          struct sk_buff *skb)
3129 {
3130         struct ieee80211_local *local = hw_to_local(hw);
3131         struct ieee80211_sub_if_data *sdata;
3132         struct ieee80211_hdr *hdr;
3133         __le16 fc;
3134         struct ieee80211_rx_data rx;
3135         struct ieee80211_sub_if_data *prev;
3136         struct sta_info *sta, *tmp, *prev_sta;
3137         int err = 0;
3138
3139         fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
3140         memset(&rx, 0, sizeof(rx));
3141         rx.skb = skb;
3142         rx.local = local;
3143
3144         if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc))
3145                 local->dot11ReceivedFragmentCount++;
3146
3147         if (ieee80211_is_mgmt(fc)) {
3148                 /* drop frame if too short for header */
3149                 if (skb->len < ieee80211_hdrlen(fc))
3150                         err = -ENOBUFS;
3151                 else
3152                         err = skb_linearize(skb);
3153         } else {
3154                 err = !pskb_may_pull(skb, ieee80211_hdrlen(fc));
3155         }
3156
3157         if (err) {
3158                 dev_kfree_skb(skb);
3159                 return;
3160         }
3161
3162         hdr = (struct ieee80211_hdr *)skb->data;
3163         ieee80211_parse_qos(&rx);
3164         ieee80211_verify_alignment(&rx);
3165
3166         if (unlikely(ieee80211_is_probe_resp(hdr->frame_control) ||
3167                      ieee80211_is_beacon(hdr->frame_control)))
3168                 ieee80211_scan_rx(local, skb);
3169
3170         if (ieee80211_is_data(fc)) {
3171                 prev_sta = NULL;
3172
3173                 for_each_sta_info(local, hdr->addr2, sta, tmp) {
3174                         if (!prev_sta) {
3175                                 prev_sta = sta;
3176                                 continue;
3177                         }
3178
3179                         rx.sta = prev_sta;
3180                         rx.sdata = prev_sta->sdata;
3181                         ieee80211_prepare_and_rx_handle(&rx, skb, false);
3182
3183                         prev_sta = sta;
3184                 }
3185
3186                 if (prev_sta) {
3187                         rx.sta = prev_sta;
3188                         rx.sdata = prev_sta->sdata;
3189
3190                         if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
3191                                 return;
3192                         goto out;
3193                 }
3194         }
3195
3196         prev = NULL;
3197
3198         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
3199                 if (!ieee80211_sdata_running(sdata))
3200                         continue;
3201
3202                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
3203                     sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
3204                         continue;
3205
3206                 /*
3207                  * frame is destined for this interface, but if it's
3208                  * not also for the previous one we handle that after
3209                  * the loop to avoid copying the SKB once too much
3210                  */
3211
3212                 if (!prev) {
3213                         prev = sdata;
3214                         continue;
3215                 }
3216
3217                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
3218                 rx.sdata = prev;
3219                 ieee80211_prepare_and_rx_handle(&rx, skb, false);
3220
3221                 prev = sdata;
3222         }
3223
3224         if (prev) {
3225                 rx.sta = sta_info_get_bss(prev, hdr->addr2);
3226                 rx.sdata = prev;
3227
3228                 if (ieee80211_prepare_and_rx_handle(&rx, skb, true))
3229                         return;
3230         }
3231
3232  out:
3233         dev_kfree_skb(skb);
3234 }
3235
3236 /*
3237  * This is the receive path handler. It is called by a low level driver when an
3238  * 802.11 MPDU is received from the hardware.
3239  */
3240 void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
3241 {
3242         struct ieee80211_local *local = hw_to_local(hw);
3243         struct ieee80211_rate *rate = NULL;
3244         struct ieee80211_supported_band *sband;
3245         struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
3246
3247         WARN_ON_ONCE(softirq_count() == 0);
3248
3249         if (WARN_ON(status->band >= IEEE80211_NUM_BANDS))
3250                 goto drop;
3251
3252         sband = local->hw.wiphy->bands[status->band];
3253         if (WARN_ON(!sband))
3254                 goto drop;
3255
3256         /*
3257          * If we're suspending, it is possible although not too likely
3258          * that we'd be receiving frames after having already partially
3259          * quiesced the stack. We can't process such frames then since
3260          * that might, for example, cause stations to be added or other
3261          * driver callbacks be invoked.
3262          */
3263         if (unlikely(local->quiescing || local->suspended))
3264                 goto drop;
3265
3266         /* We might be during a HW reconfig, prevent Rx for the same reason */
3267         if (unlikely(local->in_reconfig))
3268                 goto drop;
3269
3270         /*
3271          * The same happens when we're not even started,
3272          * but that's worth a warning.
3273          */
3274         if (WARN_ON(!local->started))
3275                 goto drop;
3276
3277         if (likely(!(status->flag & RX_FLAG_FAILED_PLCP_CRC))) {
3278                 /*
3279                  * Validate the rate, unless a PLCP error means that
3280                  * we probably can't have a valid rate here anyway.
3281                  */
3282
3283                 if (status->flag & RX_FLAG_HT) {
3284                         /*
3285                          * rate_idx is MCS index, which can be [0-76]
3286                          * as documented on:
3287                          *
3288                          * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
3289                          *
3290                          * Anything else would be some sort of driver or
3291                          * hardware error. The driver should catch hardware
3292                          * errors.
3293                          */
3294                         if (WARN(status->rate_idx > 76,
3295                                  "Rate marked as an HT rate but passed "
3296                                  "status->rate_idx is not "
3297                                  "an MCS index [0-76]: %d (0x%02x)\n",
3298                                  status->rate_idx,
3299                                  status->rate_idx))
3300                                 goto drop;
3301                 } else if (status->flag & RX_FLAG_VHT) {
3302                         if (WARN_ONCE(status->rate_idx > 9 ||
3303                                       !status->vht_nss ||
3304                                       status->vht_nss > 8,
3305                                       "Rate marked as a VHT rate but data is invalid: MCS: %d, NSS: %d\n",
3306                                       status->rate_idx, status->vht_nss))
3307                                 goto drop;
3308                 } else {
3309                         if (WARN_ON(status->rate_idx >= sband->n_bitrates))
3310                                 goto drop;
3311                         rate = &sband->bitrates[status->rate_idx];
3312                 }
3313         }
3314
3315         status->rx_flags = 0;
3316
3317         /*
3318          * key references and virtual interfaces are protected using RCU
3319          * and this requires that we are in a read-side RCU section during
3320          * receive processing
3321          */
3322         rcu_read_lock();
3323
3324         /*
3325          * Frames with failed FCS/PLCP checksum are not returned,
3326          * all other frames are returned without radiotap header
3327          * if it was previously present.
3328          * Also, frames with less than 16 bytes are dropped.
3329          */
3330         skb = ieee80211_rx_monitor(local, skb, rate);
3331         if (!skb) {
3332                 rcu_read_unlock();
3333                 return;
3334         }
3335
3336         ieee80211_tpt_led_trig_rx(local,
3337                         ((struct ieee80211_hdr *)skb->data)->frame_control,
3338                         skb->len);
3339         __ieee80211_rx_handle_packet(hw, skb);
3340
3341         rcu_read_unlock();
3342
3343         return;
3344  drop:
3345         kfree_skb(skb);
3346 }
3347 EXPORT_SYMBOL(ieee80211_rx);
3348
3349 /* This is a version of the rx handler that can be called from hard irq
3350  * context. Post the skb on the queue and schedule the tasklet */
3351 void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb)
3352 {
3353         struct ieee80211_local *local = hw_to_local(hw);
3354
3355         BUILD_BUG_ON(sizeof(struct ieee80211_rx_status) > sizeof(skb->cb));
3356
3357         skb->pkt_type = IEEE80211_RX_MSG;
3358         skb_queue_tail(&local->skb_queue, skb);
3359         tasklet_schedule(&local->tasklet);
3360 }
3361 EXPORT_SYMBOL(ieee80211_rx_irqsafe);