net/mac80211/tdls.c

   1 /*
   2  * mac80211 TDLS handling code
   3  *
   4  * Copyright 2006-2010  Johannes Berg <johannes@sipsolutions.net>
   5  * Copyright 2014, Intel Corporation
   6  * Copyright 2014  Intel Mobile Communications GmbH
   7  * Copyright 2015  Intel Deutschland GmbH
   8  *
   9  * This file is GPLv2 as found in COPYING.
  10  */
  11
  12 #include <linux/ieee80211.h>
  13 #include <linux/log2.h>
  14 #include <net/cfg80211.h>
  15 #include <linux/rtnetlink.h>
  16 #include "ieee80211_i.h"
  17 #include "driver-ops.h"
  18
  19 /* give usermode some time for retries in setting up the TDLS session */
  20 #define TDLS_PEER_SETUP_TIMEOUT (15 * HZ)
  21
  22 void ieee80211_tdls_peer_del_work(struct work_struct *wk)
  23 {
  24         struct ieee80211_sub_if_data *sdata;
  25         struct ieee80211_local *local;
  26
  27         sdata = container_of(wk, struct ieee80211_sub_if_data,
  28                              u.mgd.tdls_peer_del_work.work);
  29         local = sdata->local;
  30
  31         mutex_lock(&local->mtx);
  32         if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer)) {
  33                 tdls_dbg(sdata, "TDLS del peer %pM\n", sdata->u.mgd.tdls_peer);
  34                 sta_info_destroy_addr(sdata, sdata->u.mgd.tdls_peer);
  35                 eth_zero_addr(sdata->u.mgd.tdls_peer);
  36         }
  37         mutex_unlock(&local->mtx);
  38 }
  39
  40 static void ieee80211_tdls_add_ext_capab(struct ieee80211_sub_if_data *sdata,
  41                                          struct sk_buff *skb)
  42 {
  43         struct ieee80211_local *local = sdata->local;
  44         bool chan_switch = local->hw.wiphy->features &
  45                            NL80211_FEATURE_TDLS_CHANNEL_SWITCH;
  46         bool wider_band = ieee80211_hw_check(&local->hw, TDLS_WIDER_BW);
  47         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
  48         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
  49         bool vht = sband && sband->vht_cap.vht_supported;
  50         u8 *pos = (void *)skb_put(skb, 10);
  51
  52         *pos++ = WLAN_EID_EXT_CAPABILITY;
  53         *pos++ = 8; /* len */
  54         *pos++ = 0x0;
  55         *pos++ = 0x0;
  56         *pos++ = 0x0;
  57         *pos++ = chan_switch ? WLAN_EXT_CAPA4_TDLS_CHAN_SWITCH : 0;
  58         *pos++ = WLAN_EXT_CAPA5_TDLS_ENABLED;
  59         *pos++ = 0;
  60         *pos++ = 0;
  61         *pos++ = (vht && wider_band) ? WLAN_EXT_CAPA8_TDLS_WIDE_BW_ENABLED : 0;
  62 }
  63
  64 static u8
  65 ieee80211_tdls_add_subband(struct ieee80211_sub_if_data *sdata,
  66                            struct sk_buff *skb, u16 start, u16 end,
  67                            u16 spacing)
  68 {
  69         u8 subband_cnt = 0, ch_cnt = 0;
  70         struct ieee80211_channel *ch;
  71         struct cfg80211_chan_def chandef;
  72         int i, subband_start;
  73         struct wiphy *wiphy = sdata->local->hw.wiphy;
  74
  75         for (i = start; i <= end; i += spacing) {
  76                 if (!ch_cnt)
  77                         subband_start = i;
  78
  79                 ch = ieee80211_get_channel(sdata->local->hw.wiphy, i);
  80                 if (ch) {
  81                         /* we will be active on the channel */
  82                         cfg80211_chandef_create(&chandef, ch,
  83                                                 NL80211_CHAN_NO_HT);
  84                         if (cfg80211_reg_can_beacon_relax(wiphy, &chandef,
  85                                                           sdata->wdev.iftype)) {
  86                                 ch_cnt++;
  87                                 /*
  88                                  * check if the next channel is also part of
  89                                  * this allowed range
  90                                  */
  91                                 continue;
  92                         }
  93                 }
  94
  95                 /*
  96                  * we've reached the end of a range, with allowed channels
  97                  * found
  98                  */
  99                 if (ch_cnt) {
 100                         u8 *pos = skb_put(skb, 2);
 101                         *pos++ = ieee80211_frequency_to_channel(subband_start);
 102                         *pos++ = ch_cnt;
 103
 104                         subband_cnt++;
 105                         ch_cnt = 0;
 106                 }
 107         }
 108
 109         /* all channels in the requested range are allowed - add them here */
 110         if (ch_cnt) {
 111                 u8 *pos = skb_put(skb, 2);
 112                 *pos++ = ieee80211_frequency_to_channel(subband_start);
 113                 *pos++ = ch_cnt;
 114
 115                 subband_cnt++;
 116         }
 117
 118         return subband_cnt;
 119 }
 120
 121 static void
 122 ieee80211_tdls_add_supp_channels(struct ieee80211_sub_if_data *sdata,
 123                                  struct sk_buff *skb)
 124 {
 125         /*
 126          * Add possible channels for TDLS. These are channels that are allowed
 127          * to be active.
 128          */
 129         u8 subband_cnt;
 130         u8 *pos = skb_put(skb, 2);
 131
 132         *pos++ = WLAN_EID_SUPPORTED_CHANNELS;
 133
 134         /*
 135          * 5GHz and 2GHz channels numbers can overlap. Ignore this for now, as
 136          * this doesn't happen in real world scenarios.
 137          */
 138
 139         /* 2GHz, with 5MHz spacing */
 140         subband_cnt = ieee80211_tdls_add_subband(sdata, skb, 2412, 2472, 5);
 141
 142         /* 5GHz, with 20MHz spacing */
 143         subband_cnt += ieee80211_tdls_add_subband(sdata, skb, 5000, 5825, 20);
 144
 145         /* length */
 146         *pos = 2 * subband_cnt;
 147 }
 148
 149 static void ieee80211_tdls_add_oper_classes(struct ieee80211_sub_if_data *sdata,
 150                                             struct sk_buff *skb)
 151 {
 152         u8 *pos;
 153         u8 op_class;
 154
 155         if (!ieee80211_chandef_to_operating_class(&sdata->vif.bss_conf.chandef,
 156                                                   &op_class))
 157                 return;
 158
 159         pos = skb_put(skb, 4);
 160         *pos++ = WLAN_EID_SUPPORTED_REGULATORY_CLASSES;
 161         *pos++ = 2; /* len */
 162
 163         *pos++ = op_class;
 164         *pos++ = op_class; /* give current operating class as alternate too */
 165 }
 166
 167 static void ieee80211_tdls_add_bss_coex_ie(struct sk_buff *skb)
 168 {
 169         u8 *pos = (void *)skb_put(skb, 3);
 170
 171         *pos++ = WLAN_EID_BSS_COEX_2040;
 172         *pos++ = 1; /* len */
 173
 174         *pos++ = WLAN_BSS_COEX_INFORMATION_REQUEST;
 175 }
 176
 177 static u16 ieee80211_get_tdls_sta_capab(struct ieee80211_sub_if_data *sdata,
 178                                         u16 status_code)
 179 {
 180         /* The capability will be 0 when sending a failure code */
 181         if (status_code != 0)
 182                 return 0;
 183
 184         if (ieee80211_get_sdata_band(sdata) == IEEE80211_BAND_2GHZ) {
 185                 return WLAN_CAPABILITY_SHORT_SLOT_TIME |
 186                        WLAN_CAPABILITY_SHORT_PREAMBLE;
 187         }
 188
 189         return 0;
 190 }
 191
 192 static void ieee80211_tdls_add_link_ie(struct ieee80211_sub_if_data *sdata,
 193                                        struct sk_buff *skb, const u8 *peer,
 194                                        bool initiator)
 195 {
 196         struct ieee80211_tdls_lnkie *lnkid;
 197         const u8 *init_addr, *rsp_addr;
 198
 199         if (initiator) {
 200                 init_addr = sdata->vif.addr;
 201                 rsp_addr = peer;
 202         } else {
 203                 init_addr = peer;
 204                 rsp_addr = sdata->vif.addr;
 205         }
 206
 207         lnkid = (void *)skb_put(skb, sizeof(struct ieee80211_tdls_lnkie));
 208
 209         lnkid->ie_type = WLAN_EID_LINK_ID;
 210         lnkid->ie_len = sizeof(struct ieee80211_tdls_lnkie) - 2;
 211
 212         memcpy(lnkid->bssid, sdata->u.mgd.bssid, ETH_ALEN);
 213         memcpy(lnkid->init_sta, init_addr, ETH_ALEN);
 214         memcpy(lnkid->resp_sta, rsp_addr, ETH_ALEN);
 215 }
 216
 217 static void
 218 ieee80211_tdls_add_aid(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 219 {
 220         struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
 221         u8 *pos = (void *)skb_put(skb, 4);
 222
 223         *pos++ = WLAN_EID_AID;
 224         *pos++ = 2; /* len */
 225         put_unaligned_le16(ifmgd->aid, pos);
 226 }
 227
 228 /* translate numbering in the WMM parameter IE to the mac80211 notation */
 229 static enum ieee80211_ac_numbers ieee80211_ac_from_wmm(int ac)
 230 {
 231         switch (ac) {
 232         default:
 233                 WARN_ON_ONCE(1);
 234         case 0:
 235                 return IEEE80211_AC_BE;
 236         case 1:
 237                 return IEEE80211_AC_BK;
 238         case 2:
 239                 return IEEE80211_AC_VI;
 240         case 3:
 241                 return IEEE80211_AC_VO;
 242         }
 243 }
 244
 245 static u8 ieee80211_wmm_aci_aifsn(int aifsn, bool acm, int aci)
 246 {
 247         u8 ret;
 248
 249         ret = aifsn & 0x0f;
 250         if (acm)
 251                 ret |= 0x10;
 252         ret |= (aci << 5) & 0x60;
 253         return ret;
 254 }
 255
 256 static u8 ieee80211_wmm_ecw(u16 cw_min, u16 cw_max)
 257 {
 258         return ((ilog2(cw_min + 1) << 0x0) & 0x0f) |
 259                ((ilog2(cw_max + 1) << 0x4) & 0xf0);
 260 }
 261
 262 static void ieee80211_tdls_add_wmm_param_ie(struct ieee80211_sub_if_data *sdata,
 263                                             struct sk_buff *skb)
 264 {
 265         struct ieee80211_wmm_param_ie *wmm;
 266         struct ieee80211_tx_queue_params *txq;
 267         int i;
 268
 269         wmm = (void *)skb_put(skb, sizeof(*wmm));
 270         memset(wmm, 0, sizeof(*wmm));
 271
 272         wmm->element_id = WLAN_EID_VENDOR_SPECIFIC;
 273         wmm->len = sizeof(*wmm) - 2;
 274
 275         wmm->oui[0] = 0x00; /* Microsoft OUI 00:50:F2 */
 276         wmm->oui[1] = 0x50;
 277         wmm->oui[2] = 0xf2;
 278         wmm->oui_type = 2; /* WME */
 279         wmm->oui_subtype = 1; /* WME param */
 280         wmm->version = 1; /* WME ver */
 281         wmm->qos_info = 0; /* U-APSD not in use */
 282
 283         /*
 284          * Use the EDCA parameters defined for the BSS, or default if the AP
 285          * doesn't support it, as mandated by 802.11-2012 section 10.22.4
 286          */
 287         for (i = 0; i < IEEE80211_NUM_ACS; i++) {
 288                 txq = &sdata->tx_conf[ieee80211_ac_from_wmm(i)];
 289                 wmm->ac[i].aci_aifsn = ieee80211_wmm_aci_aifsn(txq->aifs,
 290                                                                txq->acm, i);
 291                 wmm->ac[i].cw = ieee80211_wmm_ecw(txq->cw_min, txq->cw_max);
 292                 wmm->ac[i].txop_limit = cpu_to_le16(txq->txop);
 293         }
 294 }
 295
 296 static void
 297 ieee80211_tdls_chandef_vht_upgrade(struct ieee80211_sub_if_data *sdata,
 298                                    struct sta_info *sta)
 299 {
 300         /* IEEE802.11ac-2013 Table E-4 */
 301         u16 centers_80mhz[] = { 5210, 5290, 5530, 5610, 5690, 5775 };
 302         struct cfg80211_chan_def uc = sta->tdls_chandef;
 303         enum nl80211_chan_width max_width = ieee80211_get_sta_bw(&sta->sta);
 304         int i;
 305
 306         /* only support upgrading non-narrow channels up to 80Mhz */
 307         if (max_width == NL80211_CHAN_WIDTH_5 ||
 308             max_width == NL80211_CHAN_WIDTH_10)
 309                 return;
 310
 311         if (max_width > NL80211_CHAN_WIDTH_80)
 312                 max_width = NL80211_CHAN_WIDTH_80;
 313
 314         if (uc.width == max_width)
 315                 return;
 316         /*
 317          * Channel usage constrains in the IEEE802.11ac-2013 specification only
 318          * allow expanding a 20MHz channel to 80MHz in a single way. In
 319          * addition, there are no 40MHz allowed channels that are not part of
 320          * the allowed 80MHz range in the 5GHz spectrum (the relevant one here).
 321          */
 322         for (i = 0; i < ARRAY_SIZE(centers_80mhz); i++)
 323                 if (abs(uc.chan->center_freq - centers_80mhz[i]) <= 30) {
 324                         uc.center_freq1 = centers_80mhz[i];
 325                         uc.width = NL80211_CHAN_WIDTH_80;
 326                         break;
 327                 }
 328
 329         if (!uc.center_freq1)
 330                 return;
 331
 332         /* proceed to downgrade the chandef until usable or the same */
 333         while (uc.width > max_width &&
 334                !cfg80211_reg_can_beacon(sdata->local->hw.wiphy,
 335                                         &uc, sdata->wdev.iftype))
 336                 ieee80211_chandef_downgrade(&uc);
 337
 338         if (!cfg80211_chandef_identical(&uc, &sta->tdls_chandef)) {
 339                 tdls_dbg(sdata, "TDLS ch width upgraded %d -> %d\n",
 340                          sta->tdls_chandef.width, uc.width);
 341
 342                 /*
 343                  * the station is not yet authorized when BW upgrade is done,
 344                  * locking is not required
 345                  */
 346                 sta->tdls_chandef = uc;
 347         }
 348 }
 349
 350 static void
 351 ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
 352                                    struct sk_buff *skb, const u8 *peer,
 353                                    u8 action_code, bool initiator,
 354                                    const u8 *extra_ies, size_t extra_ies_len)
 355 {
 356         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
 357         struct ieee80211_local *local = sdata->local;
 358         struct ieee80211_supported_band *sband;
 359         struct ieee80211_sta_ht_cap ht_cap;
 360         struct ieee80211_sta_vht_cap vht_cap;
 361         struct sta_info *sta = NULL;
 362         size_t offset = 0, noffset;
 363         u8 *pos;
 364
 365         ieee80211_add_srates_ie(sdata, skb, false, band);
 366         ieee80211_add_ext_srates_ie(sdata, skb, false, band);
 367         ieee80211_tdls_add_supp_channels(sdata, skb);
 368
 369         /* add any custom IEs that go before Extended Capabilities */
 370         if (extra_ies_len) {
 371                 static const u8 before_ext_cap[] = {
 372                         WLAN_EID_SUPP_RATES,
 373                         WLAN_EID_COUNTRY,
 374                         WLAN_EID_EXT_SUPP_RATES,
 375                         WLAN_EID_SUPPORTED_CHANNELS,
 376                         WLAN_EID_RSN,
 377                 };
 378                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 379                                              before_ext_cap,
 380                                              ARRAY_SIZE(before_ext_cap),
 381                                              offset);
 382                 pos = skb_put(skb, noffset - offset);
 383                 memcpy(pos, extra_ies + offset, noffset - offset);
 384                 offset = noffset;
 385         }
 386
 387         ieee80211_tdls_add_ext_capab(sdata, skb);
 388
 389         /* add the QoS element if we support it */
 390         if (local->hw.queues >= IEEE80211_NUM_ACS &&
 391             action_code != WLAN_PUB_ACTION_TDLS_DISCOVER_RES)
 392                 ieee80211_add_wmm_info_ie(skb_put(skb, 9), 0); /* no U-APSD */
 393
 394         /* add any custom IEs that go before HT capabilities */
 395         if (extra_ies_len) {
 396                 static const u8 before_ht_cap[] = {
 397                         WLAN_EID_SUPP_RATES,
 398                         WLAN_EID_COUNTRY,
 399                         WLAN_EID_EXT_SUPP_RATES,
 400                         WLAN_EID_SUPPORTED_CHANNELS,
 401                         WLAN_EID_RSN,
 402                         WLAN_EID_EXT_CAPABILITY,
 403                         WLAN_EID_QOS_CAPA,
 404                         WLAN_EID_FAST_BSS_TRANSITION,
 405                         WLAN_EID_TIMEOUT_INTERVAL,
 406                         WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
 407                 };
 408                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 409                                              before_ht_cap,
 410                                              ARRAY_SIZE(before_ht_cap),
 411                                              offset);
 412                 pos = skb_put(skb, noffset - offset);
 413                 memcpy(pos, extra_ies + offset, noffset - offset);
 414                 offset = noffset;
 415         }
 416
 417         mutex_lock(&local->sta_mtx);
 418
 419         /* we should have the peer STA if we're already responding */
 420         if (action_code == WLAN_TDLS_SETUP_RESPONSE) {
 421                 sta = sta_info_get(sdata, peer);
 422                 if (WARN_ON_ONCE(!sta)) {
 423                         mutex_unlock(&local->sta_mtx);
 424                         return;
 425                 }
 426
 427                 sta->tdls_chandef = sdata->vif.bss_conf.chandef;
 428         }
 429
 430         ieee80211_tdls_add_oper_classes(sdata, skb);
 431
 432         /*
 433          * with TDLS we can switch channels, and HT-caps are not necessarily
 434          * the same on all bands. The specification limits the setup to a
 435          * single HT-cap, so use the current band for now.
 436          */
 437         sband = local->hw.wiphy->bands[band];
 438         memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
 439
 440         if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
 441              action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) &&
 442             ht_cap.ht_supported) {
 443                 ieee80211_apply_htcap_overrides(sdata, &ht_cap);
 444
 445                 /* disable SMPS in TDLS initiator */
 446                 ht_cap.cap |= WLAN_HT_CAP_SM_PS_DISABLED
 447                                 << IEEE80211_HT_CAP_SM_PS_SHIFT;
 448
 449                 pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
 450                 ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
 451         } else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
 452                    ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
 453                 /* the peer caps are already intersected with our own */
 454                 memcpy(&ht_cap, &sta->sta.ht_cap, sizeof(ht_cap));
 455
 456                 pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
 457                 ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
 458         }
 459
 460         if (ht_cap.ht_supported &&
 461             (ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40))
 462                 ieee80211_tdls_add_bss_coex_ie(skb);
 463
 464         ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 465
 466         /* add any custom IEs that go before VHT capabilities */
 467         if (extra_ies_len) {
 468                 static const u8 before_vht_cap[] = {
 469                         WLAN_EID_SUPP_RATES,
 470                         WLAN_EID_COUNTRY,
 471                         WLAN_EID_EXT_SUPP_RATES,
 472                         WLAN_EID_SUPPORTED_CHANNELS,
 473                         WLAN_EID_RSN,
 474                         WLAN_EID_EXT_CAPABILITY,
 475                         WLAN_EID_QOS_CAPA,
 476                         WLAN_EID_FAST_BSS_TRANSITION,
 477                         WLAN_EID_TIMEOUT_INTERVAL,
 478                         WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
 479                         WLAN_EID_MULTI_BAND,
 480                 };
 481                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 482                                              before_vht_cap,
 483                                              ARRAY_SIZE(before_vht_cap),
 484                                              offset);
 485                 pos = skb_put(skb, noffset - offset);
 486                 memcpy(pos, extra_ies + offset, noffset - offset);
 487                 offset = noffset;
 488         }
 489
 490         /* build the VHT-cap similarly to the HT-cap */
 491         memcpy(&vht_cap, &sband->vht_cap, sizeof(vht_cap));
 492         if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
 493              action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) &&
 494             vht_cap.vht_supported) {
 495                 ieee80211_apply_vhtcap_overrides(sdata, &vht_cap);
 496
 497                 /* the AID is present only when VHT is implemented */
 498                 if (action_code == WLAN_TDLS_SETUP_REQUEST)
 499                         ieee80211_tdls_add_aid(sdata, skb);
 500
 501                 pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
 502                 ieee80211_ie_build_vht_cap(pos, &vht_cap, vht_cap.cap);
 503         } else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
 504                    vht_cap.vht_supported && sta->sta.vht_cap.vht_supported) {
 505                 /* the peer caps are already intersected with our own */
 506                 memcpy(&vht_cap, &sta->sta.vht_cap, sizeof(vht_cap));
 507
 508                 /* the AID is present only when VHT is implemented */
 509                 ieee80211_tdls_add_aid(sdata, skb);
 510
 511                 pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
 512                 ieee80211_ie_build_vht_cap(pos, &vht_cap, vht_cap.cap);
 513
 514                 /*
 515                  * if both peers support WIDER_BW, we can expand the chandef to
 516                  * a wider compatible one, up to 80MHz
 517                  */
 518                 if (test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW))
 519                         ieee80211_tdls_chandef_vht_upgrade(sdata, sta);
 520         }
 521
 522         mutex_unlock(&local->sta_mtx);
 523
 524         /* add any remaining IEs */
 525         if (extra_ies_len) {
 526                 noffset = extra_ies_len;
 527                 pos = skb_put(skb, noffset - offset);
 528                 memcpy(pos, extra_ies + offset, noffset - offset);
 529         }
 530
 531 }
 532
 533 static void
 534 ieee80211_tdls_add_setup_cfm_ies(struct ieee80211_sub_if_data *sdata,
 535                                  struct sk_buff *skb, const u8 *peer,
 536                                  bool initiator, const u8 *extra_ies,
 537                                  size_t extra_ies_len)
 538 {
 539         struct ieee80211_local *local = sdata->local;
 540         struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
 541         size_t offset = 0, noffset;
 542         struct sta_info *sta, *ap_sta;
 543         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
 544         u8 *pos;
 545
 546         mutex_lock(&local->sta_mtx);
 547
 548         sta = sta_info_get(sdata, peer);
 549         ap_sta = sta_info_get(sdata, ifmgd->bssid);
 550         if (WARN_ON_ONCE(!sta || !ap_sta)) {
 551                 mutex_unlock(&local->sta_mtx);
 552                 return;
 553         }
 554
 555         sta->tdls_chandef = sdata->vif.bss_conf.chandef;
 556
 557         /* add any custom IEs that go before the QoS IE */
 558         if (extra_ies_len) {
 559                 static const u8 before_qos[] = {
 560                         WLAN_EID_RSN,
 561                 };
 562                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 563                                              before_qos,
 564                                              ARRAY_SIZE(before_qos),
 565                                              offset);
 566                 pos = skb_put(skb, noffset - offset);
 567                 memcpy(pos, extra_ies + offset, noffset - offset);
 568                 offset = noffset;
 569         }
 570
 571         /* add the QoS param IE if both the peer and we support it */
 572         if (local->hw.queues >= IEEE80211_NUM_ACS && sta->sta.wme)
 573                 ieee80211_tdls_add_wmm_param_ie(sdata, skb);
 574
 575         /* add any custom IEs that go before HT operation */
 576         if (extra_ies_len) {
 577                 static const u8 before_ht_op[] = {
 578                         WLAN_EID_RSN,
 579                         WLAN_EID_QOS_CAPA,
 580                         WLAN_EID_FAST_BSS_TRANSITION,
 581                         WLAN_EID_TIMEOUT_INTERVAL,
 582                 };
 583                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 584                                              before_ht_op,
 585                                              ARRAY_SIZE(before_ht_op),
 586                                              offset);
 587                 pos = skb_put(skb, noffset - offset);
 588                 memcpy(pos, extra_ies + offset, noffset - offset);
 589                 offset = noffset;
 590         }
 591
 592         /* if HT support is only added in TDLS, we need an HT-operation IE */
 593         if (!ap_sta->sta.ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
 594                 pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
 595                 /* send an empty HT operation IE */
 596                 ieee80211_ie_build_ht_oper(pos, &sta->sta.ht_cap,
 597                                            &sdata->vif.bss_conf.chandef, 0);
 598         }
 599
 600         ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 601
 602         /* only include VHT-operation if not on the 2.4GHz band */
 603         if (band != IEEE80211_BAND_2GHZ && sta->sta.vht_cap.vht_supported) {
 604                 /*
 605                  * if both peers support WIDER_BW, we can expand the chandef to
 606                  * a wider compatible one, up to 80MHz
 607                  */
 608                 if (test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW))
 609                         ieee80211_tdls_chandef_vht_upgrade(sdata, sta);
 610
 611                 pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_operation));
 612                 ieee80211_ie_build_vht_oper(pos, &sta->sta.vht_cap,
 613                                             &sta->tdls_chandef);
 614         }
 615
 616         mutex_unlock(&local->sta_mtx);
 617
 618         /* add any remaining IEs */
 619         if (extra_ies_len) {
 620                 noffset = extra_ies_len;
 621                 pos = skb_put(skb, noffset - offset);
 622                 memcpy(pos, extra_ies + offset, noffset - offset);
 623         }
 624 }
 625
 626 static void
 627 ieee80211_tdls_add_chan_switch_req_ies(struct ieee80211_sub_if_data *sdata,
 628                                        struct sk_buff *skb, const u8 *peer,
 629                                        bool initiator, const u8 *extra_ies,
 630                                        size_t extra_ies_len, u8 oper_class,
 631                                        struct cfg80211_chan_def *chandef)
 632 {
 633         struct ieee80211_tdls_data *tf;
 634         size_t offset = 0, noffset;
 635         u8 *pos;
 636
 637         if (WARN_ON_ONCE(!chandef))
 638                 return;
 639
 640         tf = (void *)skb->data;
 641         tf->u.chan_switch_req.target_channel =
 642                 ieee80211_frequency_to_channel(chandef->chan->center_freq);
 643         tf->u.chan_switch_req.oper_class = oper_class;
 644
 645         if (extra_ies_len) {
 646                 static const u8 before_lnkie[] = {
 647                         WLAN_EID_SECONDARY_CHANNEL_OFFSET,
 648                 };
 649                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 650                                              before_lnkie,
 651                                              ARRAY_SIZE(before_lnkie),
 652                                              offset);
 653                 pos = skb_put(skb, noffset - offset);
 654                 memcpy(pos, extra_ies + offset, noffset - offset);
 655                 offset = noffset;
 656         }
 657
 658         ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 659
 660         /* add any remaining IEs */
 661         if (extra_ies_len) {
 662                 noffset = extra_ies_len;
 663                 pos = skb_put(skb, noffset - offset);
 664                 memcpy(pos, extra_ies + offset, noffset - offset);
 665         }
 666 }
 667
 668 static void
 669 ieee80211_tdls_add_chan_switch_resp_ies(struct ieee80211_sub_if_data *sdata,
 670                                         struct sk_buff *skb, const u8 *peer,
 671                                         u16 status_code, bool initiator,
 672                                         const u8 *extra_ies,
 673                                         size_t extra_ies_len)
 674 {
 675         if (status_code == 0)
 676                 ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 677
 678         if (extra_ies_len)
 679                 memcpy(skb_put(skb, extra_ies_len), extra_ies, extra_ies_len);
 680 }
 681
 682 static void ieee80211_tdls_add_ies(struct ieee80211_sub_if_data *sdata,
 683                                    struct sk_buff *skb, const u8 *peer,
 684                                    u8 action_code, u16 status_code,
 685                                    bool initiator, const u8 *extra_ies,
 686                                    size_t extra_ies_len, u8 oper_class,
 687                                    struct cfg80211_chan_def *chandef)
 688 {
 689         switch (action_code) {
 690         case WLAN_TDLS_SETUP_REQUEST:
 691         case WLAN_TDLS_SETUP_RESPONSE:
 692         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 693                 if (status_code == 0)
 694                         ieee80211_tdls_add_setup_start_ies(sdata, skb, peer,
 695                                                            action_code,
 696                                                            initiator,
 697                                                            extra_ies,
 698                                                            extra_ies_len);
 699                 break;
 700         case WLAN_TDLS_SETUP_CONFIRM:
 701                 if (status_code == 0)
 702                         ieee80211_tdls_add_setup_cfm_ies(sdata, skb, peer,
 703                                                          initiator, extra_ies,
 704                                                          extra_ies_len);
 705                 break;
 706         case WLAN_TDLS_TEARDOWN:
 707         case WLAN_TDLS_DISCOVERY_REQUEST:
 708                 if (extra_ies_len)
 709                         memcpy(skb_put(skb, extra_ies_len), extra_ies,
 710                                extra_ies_len);
 711                 if (status_code == 0 || action_code == WLAN_TDLS_TEARDOWN)
 712                         ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 713                 break;
 714         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
 715                 ieee80211_tdls_add_chan_switch_req_ies(sdata, skb, peer,
 716                                                        initiator, extra_ies,
 717                                                        extra_ies_len,
 718                                                        oper_class, chandef);
 719                 break;
 720         case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
 721                 ieee80211_tdls_add_chan_switch_resp_ies(sdata, skb, peer,
 722                                                         status_code,
 723                                                         initiator, extra_ies,
 724                                                         extra_ies_len);
 725                 break;
 726         }
 727
 728 }
 729
 730 static int
 731 ieee80211_prep_tdls_encap_data(struct wiphy *wiphy, struct net_device *dev,
 732                                const u8 *peer, u8 action_code, u8 dialog_token,
 733                                u16 status_code, struct sk_buff *skb)
 734 {
 735         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 736         struct ieee80211_tdls_data *tf;
 737
 738         tf = (void *)skb_put(skb, offsetof(struct ieee80211_tdls_data, u));
 739
 740         memcpy(tf->da, peer, ETH_ALEN);
 741         memcpy(tf->sa, sdata->vif.addr, ETH_ALEN);
 742         tf->ether_type = cpu_to_be16(ETH_P_TDLS);
 743         tf->payload_type = WLAN_TDLS_SNAP_RFTYPE;
 744
 745         /* network header is after the ethernet header */
 746         skb_set_network_header(skb, ETH_HLEN);
 747
 748         switch (action_code) {
 749         case WLAN_TDLS_SETUP_REQUEST:
 750                 tf->category = WLAN_CATEGORY_TDLS;
 751                 tf->action_code = WLAN_TDLS_SETUP_REQUEST;
 752
 753                 skb_put(skb, sizeof(tf->u.setup_req));
 754                 tf->u.setup_req.dialog_token = dialog_token;
 755                 tf->u.setup_req.capability =
 756                         cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
 757                                                                  status_code));
 758                 break;
 759         case WLAN_TDLS_SETUP_RESPONSE:
 760                 tf->category = WLAN_CATEGORY_TDLS;
 761                 tf->action_code = WLAN_TDLS_SETUP_RESPONSE;
 762
 763                 skb_put(skb, sizeof(tf->u.setup_resp));
 764                 tf->u.setup_resp.status_code = cpu_to_le16(status_code);
 765                 tf->u.setup_resp.dialog_token = dialog_token;
 766                 tf->u.setup_resp.capability =
 767                         cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
 768                                                                  status_code));
 769                 break;
 770         case WLAN_TDLS_SETUP_CONFIRM:
 771                 tf->category = WLAN_CATEGORY_TDLS;
 772                 tf->action_code = WLAN_TDLS_SETUP_CONFIRM;
 773
 774                 skb_put(skb, sizeof(tf->u.setup_cfm));
 775                 tf->u.setup_cfm.status_code = cpu_to_le16(status_code);
 776                 tf->u.setup_cfm.dialog_token = dialog_token;
 777                 break;
 778         case WLAN_TDLS_TEARDOWN:
 779                 tf->category = WLAN_CATEGORY_TDLS;
 780                 tf->action_code = WLAN_TDLS_TEARDOWN;
 781
 782                 skb_put(skb, sizeof(tf->u.teardown));
 783                 tf->u.teardown.reason_code = cpu_to_le16(status_code);
 784                 break;
 785         case WLAN_TDLS_DISCOVERY_REQUEST:
 786                 tf->category = WLAN_CATEGORY_TDLS;
 787                 tf->action_code = WLAN_TDLS_DISCOVERY_REQUEST;
 788
 789                 skb_put(skb, sizeof(tf->u.discover_req));
 790                 tf->u.discover_req.dialog_token = dialog_token;
 791                 break;
 792         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
 793                 tf->category = WLAN_CATEGORY_TDLS;
 794                 tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
 795
 796                 skb_put(skb, sizeof(tf->u.chan_switch_req));
 797                 break;
 798         case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
 799                 tf->category = WLAN_CATEGORY_TDLS;
 800                 tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
 801
 802                 skb_put(skb, sizeof(tf->u.chan_switch_resp));
 803                 tf->u.chan_switch_resp.status_code = cpu_to_le16(status_code);
 804                 break;
 805         default:
 806                 return -EINVAL;
 807         }
 808
 809         return 0;
 810 }
 811
 812 static int
 813 ieee80211_prep_tdls_direct(struct wiphy *wiphy, struct net_device *dev,
 814                            const u8 *peer, u8 action_code, u8 dialog_token,
 815                            u16 status_code, struct sk_buff *skb)
 816 {
 817         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 818         struct ieee80211_mgmt *mgmt;
 819
 820         mgmt = (void *)skb_put(skb, 24);
 821         memset(mgmt, 0, 24);
 822         memcpy(mgmt->da, peer, ETH_ALEN);
 823         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 824         memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
 825
 826         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 827                                           IEEE80211_STYPE_ACTION);
 828
 829         switch (action_code) {
 830         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 831                 skb_put(skb, 1 + sizeof(mgmt->u.action.u.tdls_discover_resp));
 832                 mgmt->u.action.category = WLAN_CATEGORY_PUBLIC;
 833                 mgmt->u.action.u.tdls_discover_resp.action_code =
 834                         WLAN_PUB_ACTION_TDLS_DISCOVER_RES;
 835                 mgmt->u.action.u.tdls_discover_resp.dialog_token =
 836                         dialog_token;
 837                 mgmt->u.action.u.tdls_discover_resp.capability =
 838                         cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
 839                                                                  status_code));
 840                 break;
 841         default:
 842                 return -EINVAL;
 843         }
 844
 845         return 0;
 846 }
 847
 848 static struct sk_buff *
 849 ieee80211_tdls_build_mgmt_packet_data(struct ieee80211_sub_if_data *sdata,
 850                                       const u8 *peer, u8 action_code,
 851                                       u8 dialog_token, u16 status_code,
 852                                       bool initiator, const u8 *extra_ies,
 853                                       size_t extra_ies_len, u8 oper_class,
 854                                       struct cfg80211_chan_def *chandef)
 855 {
 856         struct ieee80211_local *local = sdata->local;
 857         struct sk_buff *skb;
 858         int ret;
 859
 860         skb = netdev_alloc_skb(sdata->dev,
 861                                local->hw.extra_tx_headroom +
 862                                max(sizeof(struct ieee80211_mgmt),
 863                                    sizeof(struct ieee80211_tdls_data)) +
 864                                50 + /* supported rates */
 865                                10 + /* ext capab */
 866                                26 + /* max(WMM-info, WMM-param) */
 867                                2 + max(sizeof(struct ieee80211_ht_cap),
 868                                        sizeof(struct ieee80211_ht_operation)) +
 869                                2 + max(sizeof(struct ieee80211_vht_cap),
 870                                        sizeof(struct ieee80211_vht_operation)) +
 871                                50 + /* supported channels */
 872                                3 + /* 40/20 BSS coex */
 873                                4 + /* AID */
 874                                4 + /* oper classes */
 875                                extra_ies_len +
 876                                sizeof(struct ieee80211_tdls_lnkie));
 877         if (!skb)
 878                 return NULL;
 879
 880         skb_reserve(skb, local->hw.extra_tx_headroom);
 881
 882         switch (action_code) {
 883         case WLAN_TDLS_SETUP_REQUEST:
 884         case WLAN_TDLS_SETUP_RESPONSE:
 885         case WLAN_TDLS_SETUP_CONFIRM:
 886         case WLAN_TDLS_TEARDOWN:
 887         case WLAN_TDLS_DISCOVERY_REQUEST:
 888         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
 889         case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
 890                 ret = ieee80211_prep_tdls_encap_data(local->hw.wiphy,
 891                                                      sdata->dev, peer,
 892                                                      action_code, dialog_token,
 893                                                      status_code, skb);
 894                 break;
 895         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 896                 ret = ieee80211_prep_tdls_direct(local->hw.wiphy, sdata->dev,
 897                                                  peer, action_code,
 898                                                  dialog_token, status_code,
 899                                                  skb);
 900                 break;
 901         default:
 902                 ret = -ENOTSUPP;
 903                 break;
 904         }
 905
 906         if (ret < 0)
 907                 goto fail;
 908
 909         ieee80211_tdls_add_ies(sdata, skb, peer, action_code, status_code,
 910                                initiator, extra_ies, extra_ies_len, oper_class,
 911                                chandef);
 912         return skb;
 913
 914 fail:
 915         dev_kfree_skb(skb);
 916         return NULL;
 917 }
 918
 919 static int
 920 ieee80211_tdls_prep_mgmt_packet(struct wiphy *wiphy, struct net_device *dev,
 921                                 const u8 *peer, u8 action_code, u8 dialog_token,
 922                                 u16 status_code, u32 peer_capability,
 923                                 bool initiator, const u8 *extra_ies,
 924                                 size_t extra_ies_len, u8 oper_class,
 925                                 struct cfg80211_chan_def *chandef)
 926 {
 927         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 928         struct sk_buff *skb = NULL;
 929         struct sta_info *sta;
 930         u32 flags = 0;
 931         int ret = 0;
 932
 933         rcu_read_lock();
 934         sta = sta_info_get(sdata, peer);
 935
 936         /* infer the initiator if we can, to support old userspace */
 937         switch (action_code) {
 938         case WLAN_TDLS_SETUP_REQUEST:
 939                 if (sta) {
 940                         set_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
 941                         sta->sta.tdls_initiator = false;
 942                 }
 943                 /* fall-through */
 944         case WLAN_TDLS_SETUP_CONFIRM:
 945         case WLAN_TDLS_DISCOVERY_REQUEST:
 946                 initiator = true;
 947                 break;
 948         case WLAN_TDLS_SETUP_RESPONSE:
 949                 /*
 950                  * In some testing scenarios, we send a request and response.
 951                  * Make the last packet sent take effect for the initiator
 952                  * value.
 953                  */
 954                 if (sta) {
 955                         clear_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
 956                         sta->sta.tdls_initiator = true;
 957                 }
 958                 /* fall-through */
 959         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 960                 initiator = false;
 961                 break;
 962         case WLAN_TDLS_TEARDOWN:
 963         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
 964         case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
 965                 /* any value is ok */
 966                 break;
 967         default:
 968                 ret = -ENOTSUPP;
 969                 break;
 970         }
 971
 972         if (sta && test_sta_flag(sta, WLAN_STA_TDLS_INITIATOR))
 973                 initiator = true;
 974
 975         rcu_read_unlock();
 976         if (ret < 0)
 977                 goto fail;
 978
 979         skb = ieee80211_tdls_build_mgmt_packet_data(sdata, peer, action_code,
 980                                                     dialog_token, status_code,
 981                                                     initiator, extra_ies,
 982                                                     extra_ies_len, oper_class,
 983                                                     chandef);
 984         if (!skb) {
 985                 ret = -EINVAL;
 986                 goto fail;
 987         }
 988
 989         if (action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) {
 990                 ieee80211_tx_skb(sdata, skb);
 991                 return 0;
 992         }
 993
 994         /*
 995          * According to 802.11z: Setup req/resp are sent in AC_BK, otherwise
 996          * we should default to AC_VI.
 997          */
 998         switch (action_code) {
 999         case WLAN_TDLS_SETUP_REQUEST:
1000         case WLAN_TDLS_SETUP_RESPONSE:
1001                 skb_set_queue_mapping(skb, IEEE80211_AC_BK);
1002                 skb->priority = 2;
1003                 break;
1004         default:
1005                 skb_set_queue_mapping(skb, IEEE80211_AC_VI);
1006                 skb->priority = 5;
1007                 break;
1008         }
1009
1010         /*
1011          * Set the WLAN_TDLS_TEARDOWN flag to indicate a teardown in progress.
1012          * Later, if no ACK is returned from peer, we will re-send the teardown
1013          * packet through the AP.
1014          */
1015         if ((action_code == WLAN_TDLS_TEARDOWN) &&
1016             ieee80211_hw_check(&sdata->local->hw, REPORTS_TX_ACK_STATUS)) {
1017                 bool try_resend; /* Should we keep skb for possible resend */
1018
1019                 /* If not sending directly to peer - no point in keeping skb */
1020                 rcu_read_lock();
1021                 sta = sta_info_get(sdata, peer);
1022                 try_resend = sta && test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1023                 rcu_read_unlock();
1024
1025                 spin_lock_bh(&sdata->u.mgd.teardown_lock);
1026                 if (try_resend && !sdata->u.mgd.teardown_skb) {
1027                         /* Mark it as requiring TX status callback  */
1028                         flags |= IEEE80211_TX_CTL_REQ_TX_STATUS |
1029                                  IEEE80211_TX_INTFL_MLME_CONN_TX;
1030
1031                         /*
1032                          * skb is copied since mac80211 will later set
1033                          * properties that might not be the same as the AP,
1034                          * such as encryption, QoS, addresses, etc.
1035                          *
1036                          * No problem if skb_copy() fails, so no need to check.
1037                          */
1038                         sdata->u.mgd.teardown_skb = skb_copy(skb, GFP_ATOMIC);
1039                         sdata->u.mgd.orig_teardown_skb = skb;
1040                 }
1041                 spin_unlock_bh(&sdata->u.mgd.teardown_lock);
1042         }
1043
1044         /* disable bottom halves when entering the Tx path */
1045         local_bh_disable();
1046         __ieee80211_subif_start_xmit(skb, dev, flags);
1047         local_bh_enable();
1048
1049         return ret;
1050
1051 fail:
1052         dev_kfree_skb(skb);
1053         return ret;
1054 }
1055
1056 static int
1057 ieee80211_tdls_mgmt_setup(struct wiphy *wiphy, struct net_device *dev,
1058                           const u8 *peer, u8 action_code, u8 dialog_token,
1059                           u16 status_code, u32 peer_capability, bool initiator,
1060                           const u8 *extra_ies, size_t extra_ies_len)
1061 {
1062         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1063         struct ieee80211_local *local = sdata->local;
1064         enum ieee80211_smps_mode smps_mode = sdata->u.mgd.driver_smps_mode;
1065         int ret;
1066
1067         /* don't support setup with forced SMPS mode that's not off */
1068         if (smps_mode != IEEE80211_SMPS_AUTOMATIC &&
1069             smps_mode != IEEE80211_SMPS_OFF) {
1070                 tdls_dbg(sdata, "Aborting TDLS setup due to SMPS mode %d\n",
1071                          smps_mode);
1072                 return -ENOTSUPP;
1073         }
1074
1075         mutex_lock(&local->mtx);
1076
1077         /* we don't support concurrent TDLS peer setups */
1078         if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer) &&
1079             !ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
1080                 ret = -EBUSY;
1081                 goto out_unlock;
1082         }
1083
1084         /*
1085          * make sure we have a STA representing the peer so we drop or buffer
1086          * non-TDLS-setup frames to the peer. We can't send other packets
1087          * during setup through the AP path.
1088          * Allow error packets to be sent - sometimes we don't even add a STA
1089          * before failing the setup.
1090          */
1091         if (status_code == 0) {
1092                 rcu_read_lock();
1093                 if (!sta_info_get(sdata, peer)) {
1094                         rcu_read_unlock();
1095                         ret = -ENOLINK;
1096                         goto out_unlock;
1097                 }
1098                 rcu_read_unlock();
1099         }
1100
1101         ieee80211_flush_queues(local, sdata, false);
1102         memcpy(sdata->u.mgd.tdls_peer, peer, ETH_ALEN);
1103         mutex_unlock(&local->mtx);
1104
1105         /* we cannot take the mutex while preparing the setup packet */
1106         ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
1107                                               dialog_token, status_code,
1108                                               peer_capability, initiator,
1109                                               extra_ies, extra_ies_len, 0,
1110                                               NULL);
1111         if (ret < 0) {
1112                 mutex_lock(&local->mtx);
1113                 eth_zero_addr(sdata->u.mgd.tdls_peer);
1114                 mutex_unlock(&local->mtx);
1115                 return ret;
1116         }
1117
1118         ieee80211_queue_delayed_work(&sdata->local->hw,
1119                                      &sdata->u.mgd.tdls_peer_del_work,
1120                                      TDLS_PEER_SETUP_TIMEOUT);
1121         return 0;
1122
1123 out_unlock:
1124         mutex_unlock(&local->mtx);
1125         return ret;
1126 }
1127
1128 static int
1129 ieee80211_tdls_mgmt_teardown(struct wiphy *wiphy, struct net_device *dev,
1130                              const u8 *peer, u8 action_code, u8 dialog_token,
1131                              u16 status_code, u32 peer_capability,
1132                              bool initiator, const u8 *extra_ies,
1133                              size_t extra_ies_len)
1134 {
1135         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1136         struct ieee80211_local *local = sdata->local;
1137         struct sta_info *sta;
1138         int ret;
1139
1140         /*
1141          * No packets can be transmitted to the peer via the AP during setup -
1142          * the STA is set as a TDLS peer, but is not authorized.
1143          * During teardown, we prevent direct transmissions by stopping the
1144          * queues and flushing all direct packets.
1145          */
1146         ieee80211_stop_vif_queues(local, sdata,
1147                                   IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
1148         ieee80211_flush_queues(local, sdata, false);
1149
1150         ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
1151                                               dialog_token, status_code,
1152                                               peer_capability, initiator,
1153                                               extra_ies, extra_ies_len, 0,
1154                                               NULL);
1155         if (ret < 0)
1156                 sdata_err(sdata, "Failed sending TDLS teardown packet %d\n",
1157                           ret);
1158
1159         /*
1160          * Remove the STA AUTH flag to force further traffic through the AP. If
1161          * the STA was unreachable, it was already removed.
1162          */
1163         rcu_read_lock();
1164         sta = sta_info_get(sdata, peer);
1165         if (sta)
1166                 clear_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1167         rcu_read_unlock();
1168
1169         ieee80211_wake_vif_queues(local, sdata,
1170                                   IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
1171
1172         return 0;
1173 }
1174
1175 int ieee80211_tdls_mgmt(struct wiphy *wiphy, struct net_device *dev,
1176                         const u8 *peer, u8 action_code, u8 dialog_token,
1177                         u16 status_code, u32 peer_capability,
1178                         bool initiator, const u8 *extra_ies,
1179                         size_t extra_ies_len)
1180 {
1181         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1182         int ret;
1183
1184         if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
1185                 return -ENOTSUPP;
1186
1187         /* make sure we are in managed mode, and associated */
1188         if (sdata->vif.type != NL80211_IFTYPE_STATION ||
1189             !sdata->u.mgd.associated)
1190                 return -EINVAL;
1191
1192         switch (action_code) {
1193         case WLAN_TDLS_SETUP_REQUEST:
1194         case WLAN_TDLS_SETUP_RESPONSE:
1195                 ret = ieee80211_tdls_mgmt_setup(wiphy, dev, peer, action_code,
1196                                                 dialog_token, status_code,
1197                                                 peer_capability, initiator,
1198                                                 extra_ies, extra_ies_len);
1199                 break;
1200         case WLAN_TDLS_TEARDOWN:
1201                 ret = ieee80211_tdls_mgmt_teardown(wiphy, dev, peer,
1202                                                    action_code, dialog_token,
1203                                                    status_code,
1204                                                    peer_capability, initiator,
1205                                                    extra_ies, extra_ies_len);
1206                 break;
1207         case WLAN_TDLS_DISCOVERY_REQUEST:
1208                 /*
1209                  * Protect the discovery so we can hear the TDLS discovery
1210                  * response frame. It is transmitted directly and not buffered
1211                  * by the AP.
1212                  */
1213                 drv_mgd_protect_tdls_discover(sdata->local, sdata);
1214                 /* fall-through */
1215         case WLAN_TDLS_SETUP_CONFIRM:
1216         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
1217                 /* no special handling */
1218                 ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer,
1219                                                       action_code,
1220                                                       dialog_token,
1221                                                       status_code,
1222                                                       peer_capability,
1223                                                       initiator, extra_ies,
1224                                                       extra_ies_len, 0, NULL);
1225                 break;
1226         default:
1227                 ret = -EOPNOTSUPP;
1228                 break;
1229         }
1230
1231         tdls_dbg(sdata, "TDLS mgmt action %d peer %pM status %d\n",
1232                  action_code, peer, ret);
1233         return ret;
1234 }
1235
1236 static void iee80211_tdls_recalc_chanctx(struct ieee80211_sub_if_data *sdata)
1237 {
1238         struct ieee80211_local *local = sdata->local;
1239         struct ieee80211_chanctx_conf *conf;
1240         struct ieee80211_chanctx *ctx;
1241
1242         mutex_lock(&local->chanctx_mtx);
1243         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1244                                          lockdep_is_held(&local->chanctx_mtx));
1245         if (conf) {
1246                 ctx = container_of(conf, struct ieee80211_chanctx, conf);
1247                 ieee80211_recalc_chanctx_chantype(local, ctx);
1248         }
1249         mutex_unlock(&local->chanctx_mtx);
1250 }
1251
1252 static int iee80211_tdls_have_ht_peers(struct ieee80211_sub_if_data *sdata)
1253 {
1254         struct sta_info *sta;
1255         bool result = false;
1256
1257         rcu_read_lock();
1258         list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
1259                 if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
1260                     !test_sta_flag(sta, WLAN_STA_AUTHORIZED) ||
1261                     !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH) ||
1262                     !sta->sta.ht_cap.ht_supported)
1263                         continue;
1264                 result = true;
1265                 break;
1266         }
1267         rcu_read_unlock();
1268
1269         return result;
1270 }
1271
1272 static void
1273 iee80211_tdls_recalc_ht_protection(struct ieee80211_sub_if_data *sdata,
1274                                    struct sta_info *sta)
1275 {
1276         struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
1277         bool tdls_ht;
1278         u16 protection = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED |
1279                          IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT |
1280                          IEEE80211_HT_OP_MODE_NON_HT_STA_PRSNT;
1281         u16 opmode;
1282
1283         /* Nothing to do if the BSS connection uses HT */
1284         if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HT))
1285                 return;
1286
1287         tdls_ht = (sta && sta->sta.ht_cap.ht_supported) ||
1288                   iee80211_tdls_have_ht_peers(sdata);
1289
1290         opmode = sdata->vif.bss_conf.ht_operation_mode;
1291
1292         if (tdls_ht)
1293                 opmode |= protection;
1294         else
1295                 opmode &= ~protection;
1296
1297         if (opmode == sdata->vif.bss_conf.ht_operation_mode)
1298                 return;
1299
1300         sdata->vif.bss_conf.ht_operation_mode = opmode;
1301         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_HT);
1302 }
1303
1304 int ieee80211_tdls_oper(struct wiphy *wiphy, struct net_device *dev,
1305                         const u8 *peer, enum nl80211_tdls_operation oper)
1306 {
1307         struct sta_info *sta;
1308         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1309         struct ieee80211_local *local = sdata->local;
1310         int ret;
1311
1312         if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
1313                 return -ENOTSUPP;
1314
1315         if (sdata->vif.type != NL80211_IFTYPE_STATION)
1316                 return -EINVAL;
1317
1318         switch (oper) {
1319         case NL80211_TDLS_ENABLE_LINK:
1320         case NL80211_TDLS_DISABLE_LINK:
1321                 break;
1322         case NL80211_TDLS_TEARDOWN:
1323         case NL80211_TDLS_SETUP:
1324         case NL80211_TDLS_DISCOVERY_REQ:
1325                 /* We don't support in-driver setup/teardown/discovery */
1326                 return -ENOTSUPP;
1327         }
1328
1329         /* protect possible bss_conf changes and avoid concurrency in
1330          * ieee80211_bss_info_change_notify()
1331          */
1332         sdata_lock(sdata);
1333         mutex_lock(&local->mtx);
1334         tdls_dbg(sdata, "TDLS oper %d peer %pM\n", oper, peer);
1335
1336         switch (oper) {
1337         case NL80211_TDLS_ENABLE_LINK:
1338                 if (sdata->vif.csa_active) {
1339                         tdls_dbg(sdata, "TDLS: disallow link during CSA\n");
1340                         ret = -EBUSY;
1341                         break;
1342                 }
1343
1344                 iee80211_tdls_recalc_chanctx(sdata);
1345
1346                 mutex_lock(&local->sta_mtx);
1347                 sta = sta_info_get(sdata, peer);
1348                 if (!sta) {
1349                         mutex_unlock(&local->sta_mtx);
1350                         ret = -ENOLINK;
1351                         break;
1352                 }
1353
1354                 iee80211_tdls_recalc_ht_protection(sdata, sta);
1355
1356                 set_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1357                 mutex_unlock(&local->sta_mtx);
1358
1359                 WARN_ON_ONCE(is_zero_ether_addr(sdata->u.mgd.tdls_peer) ||
1360                              !ether_addr_equal(sdata->u.mgd.tdls_peer, peer));
1361                 ret = 0;
1362                 break;
1363         case NL80211_TDLS_DISABLE_LINK:
1364                 /*
1365                  * The teardown message in ieee80211_tdls_mgmt_teardown() was
1366                  * created while the queues were stopped, so it might still be
1367                  * pending. Before flushing the queues we need to be sure the
1368                  * message is handled by the tasklet handling pending messages,
1369                  * otherwise we might start destroying the station before
1370                  * sending the teardown packet.
1371                  * Note that this only forces the tasklet to flush pendings -
1372                  * not to stop the tasklet from rescheduling itself.
1373                  */
1374                 tasklet_kill(&local->tx_pending_tasklet);
1375                 /* flush a potentially queued teardown packet */
1376                 ieee80211_flush_queues(local, sdata, false);
1377
1378                 ret = sta_info_destroy_addr(sdata, peer);
1379
1380                 mutex_lock(&local->sta_mtx);
1381                 iee80211_tdls_recalc_ht_protection(sdata, NULL);
1382                 mutex_unlock(&local->sta_mtx);
1383
1384                 iee80211_tdls_recalc_chanctx(sdata);
1385                 break;
1386         default:
1387                 ret = -ENOTSUPP;
1388                 break;
1389         }
1390
1391         if (ret == 0 && ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
1392                 cancel_delayed_work(&sdata->u.mgd.tdls_peer_del_work);
1393                 eth_zero_addr(sdata->u.mgd.tdls_peer);
1394         }
1395
1396         if (ret == 0)
1397                 ieee80211_queue_work(&sdata->local->hw,
1398                                      &sdata->u.mgd.request_smps_work);
1399
1400         mutex_unlock(&local->mtx);
1401         sdata_unlock(sdata);
1402         return ret;
1403 }
1404
1405 void ieee80211_tdls_oper_request(struct ieee80211_vif *vif, const u8 *peer,
1406                                  enum nl80211_tdls_operation oper,
1407                                  u16 reason_code, gfp_t gfp)
1408 {
1409         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1410
1411         if (vif->type != NL80211_IFTYPE_STATION || !vif->bss_conf.assoc) {
1412                 sdata_err(sdata, "Discarding TDLS oper %d - not STA or disconnected\n",
1413                           oper);
1414                 return;
1415         }
1416
1417         cfg80211_tdls_oper_request(sdata->dev, peer, oper, reason_code, gfp);
1418 }
1419 EXPORT_SYMBOL(ieee80211_tdls_oper_request);
1420
1421 static void
1422 iee80211_tdls_add_ch_switch_timing(u8 *buf, u16 switch_time, u16 switch_timeout)
1423 {
1424         struct ieee80211_ch_switch_timing *ch_sw;
1425
1426         *buf++ = WLAN_EID_CHAN_SWITCH_TIMING;
1427         *buf++ = sizeof(struct ieee80211_ch_switch_timing);
1428
1429         ch_sw = (void *)buf;
1430         ch_sw->switch_time = cpu_to_le16(switch_time);
1431         ch_sw->switch_timeout = cpu_to_le16(switch_timeout);
1432 }
1433
1434 /* find switch timing IE in SKB ready for Tx */
1435 static const u8 *ieee80211_tdls_find_sw_timing_ie(struct sk_buff *skb)
1436 {
1437         struct ieee80211_tdls_data *tf;
1438         const u8 *ie_start;
1439
1440         /*
1441          * Get the offset for the new location of the switch timing IE.
1442          * The SKB network header will now point to the "payload_type"
1443          * element of the TDLS data frame struct.
1444          */
1445         tf = container_of(skb->data + skb_network_offset(skb),
1446                           struct ieee80211_tdls_data, payload_type);
1447         ie_start = tf->u.chan_switch_req.variable;
1448         return cfg80211_find_ie(WLAN_EID_CHAN_SWITCH_TIMING, ie_start,
1449                                 skb->len - (ie_start - skb->data));
1450 }
1451
1452 static struct sk_buff *
1453 ieee80211_tdls_ch_sw_tmpl_get(struct sta_info *sta, u8 oper_class,
1454                               struct cfg80211_chan_def *chandef,
1455                               u32 *ch_sw_tm_ie_offset)
1456 {
1457         struct ieee80211_sub_if_data *sdata = sta->sdata;
1458         u8 extra_ies[2 + sizeof(struct ieee80211_sec_chan_offs_ie) +
1459                      2 + sizeof(struct ieee80211_ch_switch_timing)];
1460         int extra_ies_len = 2 + sizeof(struct ieee80211_ch_switch_timing);
1461         u8 *pos = extra_ies;
1462         struct sk_buff *skb;
1463
1464         /*
1465          * if chandef points to a wide channel add a Secondary-Channel
1466          * Offset information element
1467          */
1468         if (chandef->width == NL80211_CHAN_WIDTH_40) {
1469                 struct ieee80211_sec_chan_offs_ie *sec_chan_ie;
1470                 bool ht40plus;
1471
1472                 *pos++ = WLAN_EID_SECONDARY_CHANNEL_OFFSET;
1473                 *pos++ = sizeof(*sec_chan_ie);
1474                 sec_chan_ie = (void *)pos;
1475
1476                 ht40plus = cfg80211_get_chandef_type(chandef) ==
1477                                                         NL80211_CHAN_HT40PLUS;
1478                 sec_chan_ie->sec_chan_offs = ht40plus ?
1479                                              IEEE80211_HT_PARAM_CHA_SEC_ABOVE :
1480                                              IEEE80211_HT_PARAM_CHA_SEC_BELOW;
1481                 pos += sizeof(*sec_chan_ie);
1482
1483                 extra_ies_len += 2 + sizeof(struct ieee80211_sec_chan_offs_ie);
1484         }
1485
1486         /* just set the values to 0, this is a template */
1487         iee80211_tdls_add_ch_switch_timing(pos, 0, 0);
1488
1489         skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1490                                               WLAN_TDLS_CHANNEL_SWITCH_REQUEST,
1491                                               0, 0, !sta->sta.tdls_initiator,
1492                                               extra_ies, extra_ies_len,
1493                                               oper_class, chandef);
1494         if (!skb)
1495                 return NULL;
1496
1497         skb = ieee80211_build_data_template(sdata, skb, 0);
1498         if (IS_ERR(skb)) {
1499                 tdls_dbg(sdata, "Failed building TDLS channel switch frame\n");
1500                 return NULL;
1501         }
1502
1503         if (ch_sw_tm_ie_offset) {
1504                 const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1505
1506                 if (!tm_ie) {
1507                         tdls_dbg(sdata, "No switch timing IE in TDLS switch\n");
1508                         dev_kfree_skb_any(skb);
1509                         return NULL;
1510                 }
1511
1512                 *ch_sw_tm_ie_offset = tm_ie - skb->data;
1513         }
1514
1515         tdls_dbg(sdata,
1516                  "TDLS channel switch request template for %pM ch %d width %d\n",
1517                  sta->sta.addr, chandef->chan->center_freq, chandef->width);
1518         return skb;
1519 }
1520
1521 int
1522 ieee80211_tdls_channel_switch(struct wiphy *wiphy, struct net_device *dev,
1523                               const u8 *addr, u8 oper_class,
1524                               struct cfg80211_chan_def *chandef)
1525 {
1526         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1527         struct ieee80211_local *local = sdata->local;
1528         struct sta_info *sta;
1529         struct sk_buff *skb = NULL;
1530         u32 ch_sw_tm_ie;
1531         int ret;
1532
1533         mutex_lock(&local->sta_mtx);
1534         sta = sta_info_get(sdata, addr);
1535         if (!sta) {
1536                 tdls_dbg(sdata,
1537                          "Invalid TDLS peer %pM for channel switch request\n",
1538                          addr);
1539                 ret = -ENOENT;
1540                 goto out;
1541         }
1542
1543         if (!test_sta_flag(sta, WLAN_STA_TDLS_CHAN_SWITCH)) {
1544                 tdls_dbg(sdata, "TDLS channel switch unsupported by %pM\n",
1545                          addr);
1546                 ret = -ENOTSUPP;
1547                 goto out;
1548         }
1549
1550         skb = ieee80211_tdls_ch_sw_tmpl_get(sta, oper_class, chandef,
1551                                             &ch_sw_tm_ie);
1552         if (!skb) {
1553                 ret = -ENOENT;
1554                 goto out;
1555         }
1556
1557         ret = drv_tdls_channel_switch(local, sdata, &sta->sta, oper_class,
1558                                       chandef, skb, ch_sw_tm_ie);
1559         if (!ret)
1560                 set_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1561
1562 out:
1563         mutex_unlock(&local->sta_mtx);
1564         dev_kfree_skb_any(skb);
1565         return ret;
1566 }
1567
1568 void
1569 ieee80211_tdls_cancel_channel_switch(struct wiphy *wiphy,
1570                                      struct net_device *dev,
1571                                      const u8 *addr)
1572 {
1573         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1574         struct ieee80211_local *local = sdata->local;
1575         struct sta_info *sta;
1576
1577         mutex_lock(&local->sta_mtx);
1578         sta = sta_info_get(sdata, addr);
1579         if (!sta) {
1580                 tdls_dbg(sdata,
1581                          "Invalid TDLS peer %pM for channel switch cancel\n",
1582                          addr);
1583                 goto out;
1584         }
1585
1586         if (!test_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL)) {
1587                 tdls_dbg(sdata, "TDLS channel switch not initiated by %pM\n",
1588                          addr);
1589                 goto out;
1590         }
1591
1592         drv_tdls_cancel_channel_switch(local, sdata, &sta->sta);
1593         clear_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1594
1595 out:
1596         mutex_unlock(&local->sta_mtx);
1597 }
1598
1599 static struct sk_buff *
1600 ieee80211_tdls_ch_sw_resp_tmpl_get(struct sta_info *sta,
1601                                    u32 *ch_sw_tm_ie_offset)
1602 {
1603         struct ieee80211_sub_if_data *sdata = sta->sdata;
1604         struct sk_buff *skb;
1605         u8 extra_ies[2 + sizeof(struct ieee80211_ch_switch_timing)];
1606
1607         /* initial timing are always zero in the template */
1608         iee80211_tdls_add_ch_switch_timing(extra_ies, 0, 0);
1609
1610         skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1611                                         WLAN_TDLS_CHANNEL_SWITCH_RESPONSE,
1612                                         0, 0, !sta->sta.tdls_initiator,
1613                                         extra_ies, sizeof(extra_ies), 0, NULL);
1614         if (!skb)
1615                 return NULL;
1616
1617         skb = ieee80211_build_data_template(sdata, skb, 0);
1618         if (IS_ERR(skb)) {
1619                 tdls_dbg(sdata,
1620                          "Failed building TDLS channel switch resp frame\n");
1621                 return NULL;
1622         }
1623
1624         if (ch_sw_tm_ie_offset) {
1625                 const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1626
1627                 if (!tm_ie) {
1628                         tdls_dbg(sdata,
1629                                  "No switch timing IE in TDLS switch resp\n");
1630                         dev_kfree_skb_any(skb);
1631                         return NULL;
1632                 }
1633
1634                 *ch_sw_tm_ie_offset = tm_ie - skb->data;
1635         }
1636
1637         tdls_dbg(sdata, "TDLS get channel switch response template for %pM\n",
1638                  sta->sta.addr);
1639         return skb;
1640 }
1641
1642 static int
1643 ieee80211_process_tdls_channel_switch_resp(struct ieee80211_sub_if_data *sdata,
1644                                            struct sk_buff *skb)
1645 {
1646         struct ieee80211_local *local = sdata->local;
1647         struct ieee802_11_elems elems;
1648         struct sta_info *sta;
1649         struct ieee80211_tdls_data *tf = (void *)skb->data;
1650         bool local_initiator;
1651         struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1652         int baselen = offsetof(typeof(*tf), u.chan_switch_resp.variable);
1653         struct ieee80211_tdls_ch_sw_params params = {};
1654         int ret;
1655
1656         params.action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
1657         params.timestamp = rx_status->device_timestamp;
1658
1659         if (skb->len < baselen) {
1660                 tdls_dbg(sdata, "TDLS channel switch resp too short: %d\n",
1661                          skb->len);
1662                 return -EINVAL;
1663         }
1664
1665         mutex_lock(&local->sta_mtx);
1666         sta = sta_info_get(sdata, tf->sa);
1667         if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1668                 tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1669                          tf->sa);
1670                 ret = -EINVAL;
1671                 goto out;
1672         }
1673
1674         params.sta = &sta->sta;
1675         params.status = le16_to_cpu(tf->u.chan_switch_resp.status_code);
1676         if (params.status != 0) {
1677                 ret = 0;
1678                 goto call_drv;
1679         }
1680
1681         ieee802_11_parse_elems(tf->u.chan_switch_resp.variable,
1682                                skb->len - baselen, false, &elems);
1683         if (elems.parse_error) {
1684                 tdls_dbg(sdata, "Invalid IEs in TDLS channel switch resp\n");
1685                 ret = -EINVAL;
1686                 goto out;
1687         }
1688
1689         if (!elems.ch_sw_timing || !elems.lnk_id) {
1690                 tdls_dbg(sdata, "TDLS channel switch resp - missing IEs\n");
1691                 ret = -EINVAL;
1692                 goto out;
1693         }
1694
1695         /* validate the initiator is set correctly */
1696         local_initiator =
1697                 !memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1698         if (local_initiator == sta->sta.tdls_initiator) {
1699                 tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1700                 ret = -EINVAL;
1701                 goto out;
1702         }
1703
1704         params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1705         params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1706
1707         params.tmpl_skb =
1708                 ieee80211_tdls_ch_sw_resp_tmpl_get(sta, &params.ch_sw_tm_ie);
1709         if (!params.tmpl_skb) {
1710                 ret = -ENOENT;
1711                 goto out;
1712         }
1713
1714 call_drv:
1715         drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1716
1717         tdls_dbg(sdata,
1718                  "TDLS channel switch response received from %pM status %d\n",
1719                  tf->sa, params.status);
1720
1721 out:
1722         mutex_unlock(&local->sta_mtx);
1723         dev_kfree_skb_any(params.tmpl_skb);
1724         return ret;
1725 }
1726
1727 static int
1728 ieee80211_process_tdls_channel_switch_req(struct ieee80211_sub_if_data *sdata,
1729                                           struct sk_buff *skb)
1730 {
1731         struct ieee80211_local *local = sdata->local;
1732         struct ieee802_11_elems elems;
1733         struct cfg80211_chan_def chandef;
1734         struct ieee80211_channel *chan;
1735         enum nl80211_channel_type chan_type;
1736         int freq;
1737         u8 target_channel, oper_class;
1738         bool local_initiator;
1739         struct sta_info *sta;
1740         enum ieee80211_band band;
1741         struct ieee80211_tdls_data *tf = (void *)skb->data;
1742         struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1743         int baselen = offsetof(typeof(*tf), u.chan_switch_req.variable);
1744         struct ieee80211_tdls_ch_sw_params params = {};
1745         int ret = 0;
1746
1747         params.action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
1748         params.timestamp = rx_status->device_timestamp;
1749
1750         if (skb->len < baselen) {
1751                 tdls_dbg(sdata, "TDLS channel switch req too short: %d\n",
1752                          skb->len);
1753                 return -EINVAL;
1754         }
1755
1756         target_channel = tf->u.chan_switch_req.target_channel;
1757         oper_class = tf->u.chan_switch_req.oper_class;
1758
1759         /*
1760          * We can't easily infer the channel band. The operating class is
1761          * ambiguous - there are multiple tables (US/Europe/JP/Global). The
1762          * solution here is to treat channels with number >14 as 5GHz ones,
1763          * and specifically check for the (oper_class, channel) combinations
1764          * where this doesn't hold. These are thankfully unique according to
1765          * IEEE802.11-2012.
1766          * We consider only the 2GHz and 5GHz bands and 20MHz+ channels as
1767          * valid here.
1768          */
1769         if ((oper_class == 112 || oper_class == 2 || oper_class == 3 ||
1770              oper_class == 4 || oper_class == 5 || oper_class == 6) &&
1771              target_channel < 14)
1772                 band = IEEE80211_BAND_5GHZ;
1773         else
1774                 band = target_channel < 14 ? IEEE80211_BAND_2GHZ :
1775                                              IEEE80211_BAND_5GHZ;
1776
1777         freq = ieee80211_channel_to_frequency(target_channel, band);
1778         if (freq == 0) {
1779                 tdls_dbg(sdata, "Invalid channel in TDLS chan switch: %d\n",
1780                          target_channel);
1781                 return -EINVAL;
1782         }
1783
1784         chan = ieee80211_get_channel(sdata->local->hw.wiphy, freq);
1785         if (!chan) {
1786                 tdls_dbg(sdata,
1787                          "Unsupported channel for TDLS chan switch: %d\n",
1788                          target_channel);
1789                 return -EINVAL;
1790         }
1791
1792         ieee802_11_parse_elems(tf->u.chan_switch_req.variable,
1793                                skb->len - baselen, false, &elems);
1794         if (elems.parse_error) {
1795                 tdls_dbg(sdata, "Invalid IEs in TDLS channel switch req\n");
1796                 return -EINVAL;
1797         }
1798
1799         if (!elems.ch_sw_timing || !elems.lnk_id) {
1800                 tdls_dbg(sdata, "TDLS channel switch req - missing IEs\n");
1801                 return -EINVAL;
1802         }
1803
1804         if (!elems.sec_chan_offs) {
1805                 chan_type = NL80211_CHAN_HT20;
1806         } else {
1807                 switch (elems.sec_chan_offs->sec_chan_offs) {
1808                 case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
1809                         chan_type = NL80211_CHAN_HT40PLUS;
1810                         break;
1811                 case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
1812                         chan_type = NL80211_CHAN_HT40MINUS;
1813                         break;
1814                 default:
1815                         chan_type = NL80211_CHAN_HT20;
1816                         break;
1817                 }
1818         }
1819
1820         cfg80211_chandef_create(&chandef, chan, chan_type);
1821
1822         /* we will be active on the TDLS link */
1823         if (!cfg80211_reg_can_beacon_relax(sdata->local->hw.wiphy, &chandef,
1824                                            sdata->wdev.iftype)) {
1825                 tdls_dbg(sdata, "TDLS chan switch to forbidden channel\n");
1826                 return -EINVAL;
1827         }
1828
1829         mutex_lock(&local->sta_mtx);
1830         sta = sta_info_get(sdata, tf->sa);
1831         if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1832                 tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1833                          tf->sa);
1834                 ret = -EINVAL;
1835                 goto out;
1836         }
1837
1838         params.sta = &sta->sta;
1839
1840         /* validate the initiator is set correctly */
1841         local_initiator =
1842                 !memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1843         if (local_initiator == sta->sta.tdls_initiator) {
1844                 tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1845                 ret = -EINVAL;
1846                 goto out;
1847         }
1848
1849         /* peer should have known better */
1850         if (!sta->sta.ht_cap.ht_supported && elems.sec_chan_offs &&
1851             elems.sec_chan_offs->sec_chan_offs) {
1852                 tdls_dbg(sdata, "TDLS chan switch - wide chan unsupported\n");
1853                 ret = -ENOTSUPP;
1854                 goto out;
1855         }
1856
1857         params.chandef = &chandef;
1858         params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1859         params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1860
1861         params.tmpl_skb =
1862                 ieee80211_tdls_ch_sw_resp_tmpl_get(sta,
1863                                                    &params.ch_sw_tm_ie);
1864         if (!params.tmpl_skb) {
1865                 ret = -ENOENT;
1866                 goto out;
1867         }
1868
1869         drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1870
1871         tdls_dbg(sdata,
1872                  "TDLS ch switch request received from %pM ch %d width %d\n",
1873                  tf->sa, params.chandef->chan->center_freq,
1874                  params.chandef->width);
1875 out:
1876         mutex_unlock(&local->sta_mtx);
1877         dev_kfree_skb_any(params.tmpl_skb);
1878         return ret;
1879 }
1880
1881 static void
1882 ieee80211_process_tdls_channel_switch(struct ieee80211_sub_if_data *sdata,
1883                                       struct sk_buff *skb)
1884 {
1885         struct ieee80211_tdls_data *tf = (void *)skb->data;
1886         struct wiphy *wiphy = sdata->local->hw.wiphy;
1887
1888         ASSERT_RTNL();
1889
1890         /* make sure the driver supports it */
1891         if (!(wiphy->features & NL80211_FEATURE_TDLS_CHANNEL_SWITCH))
1892                 return;
1893
1894         /* we want to access the entire packet */
1895         if (skb_linearize(skb))
1896                 return;
1897         /*
1898          * The packet/size was already validated by mac80211 Rx path, only look
1899          * at the action type.
1900          */
1901         switch (tf->action_code) {
1902         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
1903                 ieee80211_process_tdls_channel_switch_req(sdata, skb);
1904                 break;
1905         case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
1906                 ieee80211_process_tdls_channel_switch_resp(sdata, skb);
1907                 break;
1908         default:
1909                 WARN_ON_ONCE(1);
1910                 return;
1911         }
1912 }
1913
1914 void ieee80211_teardown_tdls_peers(struct ieee80211_sub_if_data *sdata)
1915 {
1916         struct sta_info *sta;
1917         u16 reason = WLAN_REASON_TDLS_TEARDOWN_UNSPECIFIED;
1918
1919         rcu_read_lock();
1920         list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
1921                 if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
1922                     !test_sta_flag(sta, WLAN_STA_AUTHORIZED))
1923                         continue;
1924
1925                 ieee80211_tdls_oper_request(&sdata->vif, sta->sta.addr,
1926                                             NL80211_TDLS_TEARDOWN, reason,
1927                                             GFP_ATOMIC);
1928         }
1929         rcu_read_unlock();
1930 }
1931
1932 void ieee80211_tdls_chsw_work(struct work_struct *wk)
1933 {
1934         struct ieee80211_local *local =
1935                 container_of(wk, struct ieee80211_local, tdls_chsw_work);
1936         struct ieee80211_sub_if_data *sdata;
1937         struct sk_buff *skb;
1938         struct ieee80211_tdls_data *tf;
1939
1940         rtnl_lock();
1941         while ((skb = skb_dequeue(&local->skb_queue_tdls_chsw))) {
1942                 tf = (struct ieee80211_tdls_data *)skb->data;
1943                 list_for_each_entry(sdata, &local->interfaces, list) {
1944                         if (!ieee80211_sdata_running(sdata) ||
1945                             sdata->vif.type != NL80211_IFTYPE_STATION ||
1946                             !ether_addr_equal(tf->da, sdata->vif.addr))
1947                                 continue;
1948
1949                         ieee80211_process_tdls_channel_switch(sdata, skb);
1950                         break;
1951                 }
1952
1953                 kfree_skb(skb);
1954         }
1955         rtnl_unlock();
1956 }