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 - 2016 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 #include "rate.h"
  19
  20 /* give usermode some time for retries in setting up the TDLS session */
  21 #define TDLS_PEER_SETUP_TIMEOUT (15 * HZ)
  22
  23 void ieee80211_tdls_peer_del_work(struct work_struct *wk)
  24 {
  25         struct ieee80211_sub_if_data *sdata;
  26         struct ieee80211_local *local;
  27
  28         sdata = container_of(wk, struct ieee80211_sub_if_data,
  29                              u.mgd.tdls_peer_del_work.work);
  30         local = sdata->local;
  31
  32         mutex_lock(&local->mtx);
  33         if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer)) {
  34                 tdls_dbg(sdata, "TDLS del peer %pM\n", sdata->u.mgd.tdls_peer);
  35                 sta_info_destroy_addr(sdata, sdata->u.mgd.tdls_peer);
  36                 eth_zero_addr(sdata->u.mgd.tdls_peer);
  37         }
  38         mutex_unlock(&local->mtx);
  39 }
  40
  41 static void ieee80211_tdls_add_ext_capab(struct ieee80211_sub_if_data *sdata,
  42                                          struct sk_buff *skb)
  43 {
  44         struct ieee80211_local *local = sdata->local;
  45         struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
  46         bool chan_switch = local->hw.wiphy->features &
  47                            NL80211_FEATURE_TDLS_CHANNEL_SWITCH;
  48         bool wider_band = ieee80211_hw_check(&local->hw, TDLS_WIDER_BW) &&
  49                           !ifmgd->tdls_wider_bw_prohibited;
  50         enum nl80211_band band = ieee80211_get_sdata_band(sdata);
  51         struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
  52         bool vht = sband && sband->vht_cap.vht_supported;
  53         u8 *pos = (void *)skb_put(skb, 10);
  54
  55         *pos++ = WLAN_EID_EXT_CAPABILITY;
  56         *pos++ = 8; /* len */
  57         *pos++ = 0x0;
  58         *pos++ = 0x0;
  59         *pos++ = 0x0;
  60         *pos++ = chan_switch ? WLAN_EXT_CAPA4_TDLS_CHAN_SWITCH : 0;
  61         *pos++ = WLAN_EXT_CAPA5_TDLS_ENABLED;
  62         *pos++ = 0;
  63         *pos++ = 0;
  64         *pos++ = (vht && wider_band) ? WLAN_EXT_CAPA8_TDLS_WIDE_BW_ENABLED : 0;
  65 }
  66
  67 static u8
  68 ieee80211_tdls_add_subband(struct ieee80211_sub_if_data *sdata,
  69                            struct sk_buff *skb, u16 start, u16 end,
  70                            u16 spacing)
  71 {
  72         u8 subband_cnt = 0, ch_cnt = 0;
  73         struct ieee80211_channel *ch;
  74         struct cfg80211_chan_def chandef;
  75         int i, subband_start;
  76         struct wiphy *wiphy = sdata->local->hw.wiphy;
  77
  78         for (i = start; i <= end; i += spacing) {
  79                 if (!ch_cnt)
  80                         subband_start = i;
  81
  82                 ch = ieee80211_get_channel(sdata->local->hw.wiphy, i);
  83                 if (ch) {
  84                         /* we will be active on the channel */
  85                         cfg80211_chandef_create(&chandef, ch,
  86                                                 NL80211_CHAN_NO_HT);
  87                         if (cfg80211_reg_can_beacon_relax(wiphy, &chandef,
  88                                                           sdata->wdev.iftype)) {
  89                                 ch_cnt++;
  90                                 /*
  91                                  * check if the next channel is also part of
  92                                  * this allowed range
  93                                  */
  94                                 continue;
  95                         }
  96                 }
  97
  98                 /*
  99                  * we've reached the end of a range, with allowed channels
 100                  * found
 101                  */
 102                 if (ch_cnt) {
 103                         u8 *pos = skb_put(skb, 2);
 104                         *pos++ = ieee80211_frequency_to_channel(subband_start);
 105                         *pos++ = ch_cnt;
 106
 107                         subband_cnt++;
 108                         ch_cnt = 0;
 109                 }
 110         }
 111
 112         /* all channels in the requested range are allowed - add them here */
 113         if (ch_cnt) {
 114                 u8 *pos = skb_put(skb, 2);
 115                 *pos++ = ieee80211_frequency_to_channel(subband_start);
 116                 *pos++ = ch_cnt;
 117
 118                 subband_cnt++;
 119         }
 120
 121         return subband_cnt;
 122 }
 123
 124 static void
 125 ieee80211_tdls_add_supp_channels(struct ieee80211_sub_if_data *sdata,
 126                                  struct sk_buff *skb)
 127 {
 128         /*
 129          * Add possible channels for TDLS. These are channels that are allowed
 130          * to be active.
 131          */
 132         u8 subband_cnt;
 133         u8 *pos = skb_put(skb, 2);
 134
 135         *pos++ = WLAN_EID_SUPPORTED_CHANNELS;
 136
 137         /*
 138          * 5GHz and 2GHz channels numbers can overlap. Ignore this for now, as
 139          * this doesn't happen in real world scenarios.
 140          */
 141
 142         /* 2GHz, with 5MHz spacing */
 143         subband_cnt = ieee80211_tdls_add_subband(sdata, skb, 2412, 2472, 5);
 144
 145         /* 5GHz, with 20MHz spacing */
 146         subband_cnt += ieee80211_tdls_add_subband(sdata, skb, 5000, 5825, 20);
 147
 148         /* length */
 149         *pos = 2 * subband_cnt;
 150 }
 151
 152 static void ieee80211_tdls_add_oper_classes(struct ieee80211_sub_if_data *sdata,
 153                                             struct sk_buff *skb)
 154 {
 155         u8 *pos;
 156         u8 op_class;
 157
 158         if (!ieee80211_chandef_to_operating_class(&sdata->vif.bss_conf.chandef,
 159                                                   &op_class))
 160                 return;
 161
 162         pos = skb_put(skb, 4);
 163         *pos++ = WLAN_EID_SUPPORTED_REGULATORY_CLASSES;
 164         *pos++ = 2; /* len */
 165
 166         *pos++ = op_class;
 167         *pos++ = op_class; /* give current operating class as alternate too */
 168 }
 169
 170 static void ieee80211_tdls_add_bss_coex_ie(struct sk_buff *skb)
 171 {
 172         u8 *pos = (void *)skb_put(skb, 3);
 173
 174         *pos++ = WLAN_EID_BSS_COEX_2040;
 175         *pos++ = 1; /* len */
 176
 177         *pos++ = WLAN_BSS_COEX_INFORMATION_REQUEST;
 178 }
 179
 180 static u16 ieee80211_get_tdls_sta_capab(struct ieee80211_sub_if_data *sdata,
 181                                         u16 status_code)
 182 {
 183         /* The capability will be 0 when sending a failure code */
 184         if (status_code != 0)
 185                 return 0;
 186
 187         if (ieee80211_get_sdata_band(sdata) == NL80211_BAND_2GHZ) {
 188                 return WLAN_CAPABILITY_SHORT_SLOT_TIME |
 189                        WLAN_CAPABILITY_SHORT_PREAMBLE;
 190         }
 191
 192         return 0;
 193 }
 194
 195 static void ieee80211_tdls_add_link_ie(struct ieee80211_sub_if_data *sdata,
 196                                        struct sk_buff *skb, const u8 *peer,
 197                                        bool initiator)
 198 {
 199         struct ieee80211_tdls_lnkie *lnkid;
 200         const u8 *init_addr, *rsp_addr;
 201
 202         if (initiator) {
 203                 init_addr = sdata->vif.addr;
 204                 rsp_addr = peer;
 205         } else {
 206                 init_addr = peer;
 207                 rsp_addr = sdata->vif.addr;
 208         }
 209
 210         lnkid = (void *)skb_put(skb, sizeof(struct ieee80211_tdls_lnkie));
 211
 212         lnkid->ie_type = WLAN_EID_LINK_ID;
 213         lnkid->ie_len = sizeof(struct ieee80211_tdls_lnkie) - 2;
 214
 215         memcpy(lnkid->bssid, sdata->u.mgd.bssid, ETH_ALEN);
 216         memcpy(lnkid->init_sta, init_addr, ETH_ALEN);
 217         memcpy(lnkid->resp_sta, rsp_addr, ETH_ALEN);
 218 }
 219
 220 static void
 221 ieee80211_tdls_add_aid(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
 222 {
 223         struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
 224         u8 *pos = (void *)skb_put(skb, 4);
 225
 226         *pos++ = WLAN_EID_AID;
 227         *pos++ = 2; /* len */
 228         put_unaligned_le16(ifmgd->aid, pos);
 229 }
 230
 231 /* translate numbering in the WMM parameter IE to the mac80211 notation */
 232 static enum ieee80211_ac_numbers ieee80211_ac_from_wmm(int ac)
 233 {
 234         switch (ac) {
 235         default:
 236                 WARN_ON_ONCE(1);
 237         case 0:
 238                 return IEEE80211_AC_BE;
 239         case 1:
 240                 return IEEE80211_AC_BK;
 241         case 2:
 242                 return IEEE80211_AC_VI;
 243         case 3:
 244                 return IEEE80211_AC_VO;
 245         }
 246 }
 247
 248 static u8 ieee80211_wmm_aci_aifsn(int aifsn, bool acm, int aci)
 249 {
 250         u8 ret;
 251
 252         ret = aifsn & 0x0f;
 253         if (acm)
 254                 ret |= 0x10;
 255         ret |= (aci << 5) & 0x60;
 256         return ret;
 257 }
 258
 259 static u8 ieee80211_wmm_ecw(u16 cw_min, u16 cw_max)
 260 {
 261         return ((ilog2(cw_min + 1) << 0x0) & 0x0f) |
 262                ((ilog2(cw_max + 1) << 0x4) & 0xf0);
 263 }
 264
 265 static void ieee80211_tdls_add_wmm_param_ie(struct ieee80211_sub_if_data *sdata,
 266                                             struct sk_buff *skb)
 267 {
 268         struct ieee80211_wmm_param_ie *wmm;
 269         struct ieee80211_tx_queue_params *txq;
 270         int i;
 271
 272         wmm = (void *)skb_put(skb, sizeof(*wmm));
 273         memset(wmm, 0, sizeof(*wmm));
 274
 275         wmm->element_id = WLAN_EID_VENDOR_SPECIFIC;
 276         wmm->len = sizeof(*wmm) - 2;
 277
 278         wmm->oui[0] = 0x00; /* Microsoft OUI 00:50:F2 */
 279         wmm->oui[1] = 0x50;
 280         wmm->oui[2] = 0xf2;
 281         wmm->oui_type = 2; /* WME */
 282         wmm->oui_subtype = 1; /* WME param */
 283         wmm->version = 1; /* WME ver */
 284         wmm->qos_info = 0; /* U-APSD not in use */
 285
 286         /*
 287          * Use the EDCA parameters defined for the BSS, or default if the AP
 288          * doesn't support it, as mandated by 802.11-2012 section 10.22.4
 289          */
 290         for (i = 0; i < IEEE80211_NUM_ACS; i++) {
 291                 txq = &sdata->tx_conf[ieee80211_ac_from_wmm(i)];
 292                 wmm->ac[i].aci_aifsn = ieee80211_wmm_aci_aifsn(txq->aifs,
 293                                                                txq->acm, i);
 294                 wmm->ac[i].cw = ieee80211_wmm_ecw(txq->cw_min, txq->cw_max);
 295                 wmm->ac[i].txop_limit = cpu_to_le16(txq->txop);
 296         }
 297 }
 298
 299 static void
 300 ieee80211_tdls_chandef_vht_upgrade(struct ieee80211_sub_if_data *sdata,
 301                                    struct sta_info *sta)
 302 {
 303         /* IEEE802.11ac-2013 Table E-4 */
 304         u16 centers_80mhz[] = { 5210, 5290, 5530, 5610, 5690, 5775 };
 305         struct cfg80211_chan_def uc = sta->tdls_chandef;
 306         enum nl80211_chan_width max_width = ieee80211_sta_cap_chan_bw(sta);
 307         int i;
 308
 309         /* only support upgrading non-narrow channels up to 80Mhz */
 310         if (max_width == NL80211_CHAN_WIDTH_5 ||
 311             max_width == NL80211_CHAN_WIDTH_10)
 312                 return;
 313
 314         if (max_width > NL80211_CHAN_WIDTH_80)
 315                 max_width = NL80211_CHAN_WIDTH_80;
 316
 317         if (uc.width >= max_width)
 318                 return;
 319         /*
 320          * Channel usage constrains in the IEEE802.11ac-2013 specification only
 321          * allow expanding a 20MHz channel to 80MHz in a single way. In
 322          * addition, there are no 40MHz allowed channels that are not part of
 323          * the allowed 80MHz range in the 5GHz spectrum (the relevant one here).
 324          */
 325         for (i = 0; i < ARRAY_SIZE(centers_80mhz); i++)
 326                 if (abs(uc.chan->center_freq - centers_80mhz[i]) <= 30) {
 327                         uc.center_freq1 = centers_80mhz[i];
 328                         uc.center_freq2 = 0;
 329                         uc.width = NL80211_CHAN_WIDTH_80;
 330                         break;
 331                 }
 332
 333         if (!uc.center_freq1)
 334                 return;
 335
 336         /* proceed to downgrade the chandef until usable or the same */
 337         while (uc.width > max_width ||
 338                !cfg80211_reg_can_beacon_relax(sdata->local->hw.wiphy, &uc,
 339                                               sdata->wdev.iftype))
 340                 ieee80211_chandef_downgrade(&uc);
 341
 342         if (!cfg80211_chandef_identical(&uc, &sta->tdls_chandef)) {
 343                 tdls_dbg(sdata, "TDLS ch width upgraded %d -> %d\n",
 344                          sta->tdls_chandef.width, uc.width);
 345
 346                 /*
 347                  * the station is not yet authorized when BW upgrade is done,
 348                  * locking is not required
 349                  */
 350                 sta->tdls_chandef = uc;
 351         }
 352 }
 353
 354 static void
 355 ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
 356                                    struct sk_buff *skb, const u8 *peer,
 357                                    u8 action_code, bool initiator,
 358                                    const u8 *extra_ies, size_t extra_ies_len)
 359 {
 360         enum nl80211_band band = ieee80211_get_sdata_band(sdata);
 361         struct ieee80211_local *local = sdata->local;
 362         struct ieee80211_supported_band *sband;
 363         struct ieee80211_sta_ht_cap ht_cap;
 364         struct ieee80211_sta_vht_cap vht_cap;
 365         struct sta_info *sta = NULL;
 366         size_t offset = 0, noffset;
 367         u8 *pos;
 368
 369         ieee80211_add_srates_ie(sdata, skb, false, band);
 370         ieee80211_add_ext_srates_ie(sdata, skb, false, band);
 371         ieee80211_tdls_add_supp_channels(sdata, skb);
 372
 373         /* add any custom IEs that go before Extended Capabilities */
 374         if (extra_ies_len) {
 375                 static const u8 before_ext_cap[] = {
 376                         WLAN_EID_SUPP_RATES,
 377                         WLAN_EID_COUNTRY,
 378                         WLAN_EID_EXT_SUPP_RATES,
 379                         WLAN_EID_SUPPORTED_CHANNELS,
 380                         WLAN_EID_RSN,
 381                 };
 382                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 383                                              before_ext_cap,
 384                                              ARRAY_SIZE(before_ext_cap),
 385                                              offset);
 386                 pos = skb_put(skb, noffset - offset);
 387                 memcpy(pos, extra_ies + offset, noffset - offset);
 388                 offset = noffset;
 389         }
 390
 391         ieee80211_tdls_add_ext_capab(sdata, skb);
 392
 393         /* add the QoS element if we support it */
 394         if (local->hw.queues >= IEEE80211_NUM_ACS &&
 395             action_code != WLAN_PUB_ACTION_TDLS_DISCOVER_RES)
 396                 ieee80211_add_wmm_info_ie(skb_put(skb, 9), 0); /* no U-APSD */
 397
 398         /* add any custom IEs that go before HT capabilities */
 399         if (extra_ies_len) {
 400                 static const u8 before_ht_cap[] = {
 401                         WLAN_EID_SUPP_RATES,
 402                         WLAN_EID_COUNTRY,
 403                         WLAN_EID_EXT_SUPP_RATES,
 404                         WLAN_EID_SUPPORTED_CHANNELS,
 405                         WLAN_EID_RSN,
 406                         WLAN_EID_EXT_CAPABILITY,
 407                         WLAN_EID_QOS_CAPA,
 408                         WLAN_EID_FAST_BSS_TRANSITION,
 409                         WLAN_EID_TIMEOUT_INTERVAL,
 410                         WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
 411                 };
 412                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 413                                              before_ht_cap,
 414                                              ARRAY_SIZE(before_ht_cap),
 415                                              offset);
 416                 pos = skb_put(skb, noffset - offset);
 417                 memcpy(pos, extra_ies + offset, noffset - offset);
 418                 offset = noffset;
 419         }
 420
 421         mutex_lock(&local->sta_mtx);
 422
 423         /* we should have the peer STA if we're already responding */
 424         if (action_code == WLAN_TDLS_SETUP_RESPONSE) {
 425                 sta = sta_info_get(sdata, peer);
 426                 if (WARN_ON_ONCE(!sta)) {
 427                         mutex_unlock(&local->sta_mtx);
 428                         return;
 429                 }
 430
 431                 sta->tdls_chandef = sdata->vif.bss_conf.chandef;
 432         }
 433
 434         ieee80211_tdls_add_oper_classes(sdata, skb);
 435
 436         /*
 437          * with TDLS we can switch channels, and HT-caps are not necessarily
 438          * the same on all bands. The specification limits the setup to a
 439          * single HT-cap, so use the current band for now.
 440          */
 441         sband = local->hw.wiphy->bands[band];
 442         memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
 443
 444         if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
 445              action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) &&
 446             ht_cap.ht_supported) {
 447                 ieee80211_apply_htcap_overrides(sdata, &ht_cap);
 448
 449                 /* disable SMPS in TDLS initiator */
 450                 ht_cap.cap |= WLAN_HT_CAP_SM_PS_DISABLED
 451                                 << IEEE80211_HT_CAP_SM_PS_SHIFT;
 452
 453                 pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
 454                 ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
 455         } else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
 456                    ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
 457                 /* the peer caps are already intersected with our own */
 458                 memcpy(&ht_cap, &sta->sta.ht_cap, sizeof(ht_cap));
 459
 460                 pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
 461                 ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
 462         }
 463
 464         if (ht_cap.ht_supported &&
 465             (ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40))
 466                 ieee80211_tdls_add_bss_coex_ie(skb);
 467
 468         ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 469
 470         /* add any custom IEs that go before VHT capabilities */
 471         if (extra_ies_len) {
 472                 static const u8 before_vht_cap[] = {
 473                         WLAN_EID_SUPP_RATES,
 474                         WLAN_EID_COUNTRY,
 475                         WLAN_EID_EXT_SUPP_RATES,
 476                         WLAN_EID_SUPPORTED_CHANNELS,
 477                         WLAN_EID_RSN,
 478                         WLAN_EID_EXT_CAPABILITY,
 479                         WLAN_EID_QOS_CAPA,
 480                         WLAN_EID_FAST_BSS_TRANSITION,
 481                         WLAN_EID_TIMEOUT_INTERVAL,
 482                         WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
 483                         WLAN_EID_MULTI_BAND,
 484                 };
 485                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 486                                              before_vht_cap,
 487                                              ARRAY_SIZE(before_vht_cap),
 488                                              offset);
 489                 pos = skb_put(skb, noffset - offset);
 490                 memcpy(pos, extra_ies + offset, noffset - offset);
 491                 offset = noffset;
 492         }
 493
 494         /* build the VHT-cap similarly to the HT-cap */
 495         memcpy(&vht_cap, &sband->vht_cap, sizeof(vht_cap));
 496         if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
 497              action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) &&
 498             vht_cap.vht_supported) {
 499                 ieee80211_apply_vhtcap_overrides(sdata, &vht_cap);
 500
 501                 /* the AID is present only when VHT is implemented */
 502                 if (action_code == WLAN_TDLS_SETUP_REQUEST)
 503                         ieee80211_tdls_add_aid(sdata, skb);
 504
 505                 pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
 506                 ieee80211_ie_build_vht_cap(pos, &vht_cap, vht_cap.cap);
 507         } else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
 508                    vht_cap.vht_supported && sta->sta.vht_cap.vht_supported) {
 509                 /* the peer caps are already intersected with our own */
 510                 memcpy(&vht_cap, &sta->sta.vht_cap, sizeof(vht_cap));
 511
 512                 /* the AID is present only when VHT is implemented */
 513                 ieee80211_tdls_add_aid(sdata, skb);
 514
 515                 pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
 516                 ieee80211_ie_build_vht_cap(pos, &vht_cap, vht_cap.cap);
 517
 518                 /*
 519                  * if both peers support WIDER_BW, we can expand the chandef to
 520                  * a wider compatible one, up to 80MHz
 521                  */
 522                 if (test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW))
 523                         ieee80211_tdls_chandef_vht_upgrade(sdata, sta);
 524         }
 525
 526         mutex_unlock(&local->sta_mtx);
 527
 528         /* add any remaining IEs */
 529         if (extra_ies_len) {
 530                 noffset = extra_ies_len;
 531                 pos = skb_put(skb, noffset - offset);
 532                 memcpy(pos, extra_ies + offset, noffset - offset);
 533         }
 534
 535 }
 536
 537 static void
 538 ieee80211_tdls_add_setup_cfm_ies(struct ieee80211_sub_if_data *sdata,
 539                                  struct sk_buff *skb, const u8 *peer,
 540                                  bool initiator, const u8 *extra_ies,
 541                                  size_t extra_ies_len)
 542 {
 543         struct ieee80211_local *local = sdata->local;
 544         struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
 545         size_t offset = 0, noffset;
 546         struct sta_info *sta, *ap_sta;
 547         enum nl80211_band band = ieee80211_get_sdata_band(sdata);
 548         u8 *pos;
 549
 550         mutex_lock(&local->sta_mtx);
 551
 552         sta = sta_info_get(sdata, peer);
 553         ap_sta = sta_info_get(sdata, ifmgd->bssid);
 554         if (WARN_ON_ONCE(!sta || !ap_sta)) {
 555                 mutex_unlock(&local->sta_mtx);
 556                 return;
 557         }
 558
 559         sta->tdls_chandef = sdata->vif.bss_conf.chandef;
 560
 561         /* add any custom IEs that go before the QoS IE */
 562         if (extra_ies_len) {
 563                 static const u8 before_qos[] = {
 564                         WLAN_EID_RSN,
 565                 };
 566                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 567                                              before_qos,
 568                                              ARRAY_SIZE(before_qos),
 569                                              offset);
 570                 pos = skb_put(skb, noffset - offset);
 571                 memcpy(pos, extra_ies + offset, noffset - offset);
 572                 offset = noffset;
 573         }
 574
 575         /* add the QoS param IE if both the peer and we support it */
 576         if (local->hw.queues >= IEEE80211_NUM_ACS && sta->sta.wme)
 577                 ieee80211_tdls_add_wmm_param_ie(sdata, skb);
 578
 579         /* add any custom IEs that go before HT operation */
 580         if (extra_ies_len) {
 581                 static const u8 before_ht_op[] = {
 582                         WLAN_EID_RSN,
 583                         WLAN_EID_QOS_CAPA,
 584                         WLAN_EID_FAST_BSS_TRANSITION,
 585                         WLAN_EID_TIMEOUT_INTERVAL,
 586                 };
 587                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 588                                              before_ht_op,
 589                                              ARRAY_SIZE(before_ht_op),
 590                                              offset);
 591                 pos = skb_put(skb, noffset - offset);
 592                 memcpy(pos, extra_ies + offset, noffset - offset);
 593                 offset = noffset;
 594         }
 595
 596         /*
 597          * if HT support is only added in TDLS, we need an HT-operation IE.
 598          * add the IE as required by IEEE802.11-2012 9.23.3.2.
 599          */
 600         if (!ap_sta->sta.ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
 601                 u16 prot = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED |
 602                            IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT |
 603                            IEEE80211_HT_OP_MODE_NON_HT_STA_PRSNT;
 604
 605                 pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
 606                 ieee80211_ie_build_ht_oper(pos, &sta->sta.ht_cap,
 607                                            &sdata->vif.bss_conf.chandef, prot,
 608                                            true);
 609         }
 610
 611         ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 612
 613         /* only include VHT-operation if not on the 2.4GHz band */
 614         if (band != NL80211_BAND_2GHZ && sta->sta.vht_cap.vht_supported) {
 615                 /*
 616                  * if both peers support WIDER_BW, we can expand the chandef to
 617                  * a wider compatible one, up to 80MHz
 618                  */
 619                 if (test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW))
 620                         ieee80211_tdls_chandef_vht_upgrade(sdata, sta);
 621
 622                 pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_operation));
 623                 ieee80211_ie_build_vht_oper(pos, &sta->sta.vht_cap,
 624                                             &sta->tdls_chandef);
 625         }
 626
 627         mutex_unlock(&local->sta_mtx);
 628
 629         /* add any remaining IEs */
 630         if (extra_ies_len) {
 631                 noffset = extra_ies_len;
 632                 pos = skb_put(skb, noffset - offset);
 633                 memcpy(pos, extra_ies + offset, noffset - offset);
 634         }
 635 }
 636
 637 static void
 638 ieee80211_tdls_add_chan_switch_req_ies(struct ieee80211_sub_if_data *sdata,
 639                                        struct sk_buff *skb, const u8 *peer,
 640                                        bool initiator, const u8 *extra_ies,
 641                                        size_t extra_ies_len, u8 oper_class,
 642                                        struct cfg80211_chan_def *chandef)
 643 {
 644         struct ieee80211_tdls_data *tf;
 645         size_t offset = 0, noffset;
 646         u8 *pos;
 647
 648         if (WARN_ON_ONCE(!chandef))
 649                 return;
 650
 651         tf = (void *)skb->data;
 652         tf->u.chan_switch_req.target_channel =
 653                 ieee80211_frequency_to_channel(chandef->chan->center_freq);
 654         tf->u.chan_switch_req.oper_class = oper_class;
 655
 656         if (extra_ies_len) {
 657                 static const u8 before_lnkie[] = {
 658                         WLAN_EID_SECONDARY_CHANNEL_OFFSET,
 659                 };
 660                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 661                                              before_lnkie,
 662                                              ARRAY_SIZE(before_lnkie),
 663                                              offset);
 664                 pos = skb_put(skb, noffset - offset);
 665                 memcpy(pos, extra_ies + offset, noffset - offset);
 666                 offset = noffset;
 667         }
 668
 669         ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 670
 671         /* add any remaining IEs */
 672         if (extra_ies_len) {
 673                 noffset = extra_ies_len;
 674                 pos = skb_put(skb, noffset - offset);
 675                 memcpy(pos, extra_ies + offset, noffset - offset);
 676         }
 677 }
 678
 679 static void
 680 ieee80211_tdls_add_chan_switch_resp_ies(struct ieee80211_sub_if_data *sdata,
 681                                         struct sk_buff *skb, const u8 *peer,
 682                                         u16 status_code, bool initiator,
 683                                         const u8 *extra_ies,
 684                                         size_t extra_ies_len)
 685 {
 686         if (status_code == 0)
 687                 ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 688
 689         if (extra_ies_len)
 690                 memcpy(skb_put(skb, extra_ies_len), extra_ies, extra_ies_len);
 691 }
 692
 693 static void ieee80211_tdls_add_ies(struct ieee80211_sub_if_data *sdata,
 694                                    struct sk_buff *skb, const u8 *peer,
 695                                    u8 action_code, u16 status_code,
 696                                    bool initiator, const u8 *extra_ies,
 697                                    size_t extra_ies_len, u8 oper_class,
 698                                    struct cfg80211_chan_def *chandef)
 699 {
 700         switch (action_code) {
 701         case WLAN_TDLS_SETUP_REQUEST:
 702         case WLAN_TDLS_SETUP_RESPONSE:
 703         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 704                 if (status_code == 0)
 705                         ieee80211_tdls_add_setup_start_ies(sdata, skb, peer,
 706                                                            action_code,
 707                                                            initiator,
 708                                                            extra_ies,
 709                                                            extra_ies_len);
 710                 break;
 711         case WLAN_TDLS_SETUP_CONFIRM:
 712                 if (status_code == 0)
 713                         ieee80211_tdls_add_setup_cfm_ies(sdata, skb, peer,
 714                                                          initiator, extra_ies,
 715                                                          extra_ies_len);
 716                 break;
 717         case WLAN_TDLS_TEARDOWN:
 718         case WLAN_TDLS_DISCOVERY_REQUEST:
 719                 if (extra_ies_len)
 720                         memcpy(skb_put(skb, extra_ies_len), extra_ies,
 721                                extra_ies_len);
 722                 if (status_code == 0 || action_code == WLAN_TDLS_TEARDOWN)
 723                         ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 724                 break;
 725         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
 726                 ieee80211_tdls_add_chan_switch_req_ies(sdata, skb, peer,
 727                                                        initiator, extra_ies,
 728                                                        extra_ies_len,
 729                                                        oper_class, chandef);
 730                 break;
 731         case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
 732                 ieee80211_tdls_add_chan_switch_resp_ies(sdata, skb, peer,
 733                                                         status_code,
 734                                                         initiator, extra_ies,
 735                                                         extra_ies_len);
 736                 break;
 737         }
 738
 739 }
 740
 741 static int
 742 ieee80211_prep_tdls_encap_data(struct wiphy *wiphy, struct net_device *dev,
 743                                const u8 *peer, u8 action_code, u8 dialog_token,
 744                                u16 status_code, struct sk_buff *skb)
 745 {
 746         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 747         struct ieee80211_tdls_data *tf;
 748
 749         tf = (void *)skb_put(skb, offsetof(struct ieee80211_tdls_data, u));
 750
 751         memcpy(tf->da, peer, ETH_ALEN);
 752         memcpy(tf->sa, sdata->vif.addr, ETH_ALEN);
 753         tf->ether_type = cpu_to_be16(ETH_P_TDLS);
 754         tf->payload_type = WLAN_TDLS_SNAP_RFTYPE;
 755
 756         /* network header is after the ethernet header */
 757         skb_set_network_header(skb, ETH_HLEN);
 758
 759         switch (action_code) {
 760         case WLAN_TDLS_SETUP_REQUEST:
 761                 tf->category = WLAN_CATEGORY_TDLS;
 762                 tf->action_code = WLAN_TDLS_SETUP_REQUEST;
 763
 764                 skb_put(skb, sizeof(tf->u.setup_req));
 765                 tf->u.setup_req.dialog_token = dialog_token;
 766                 tf->u.setup_req.capability =
 767                         cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
 768                                                                  status_code));
 769                 break;
 770         case WLAN_TDLS_SETUP_RESPONSE:
 771                 tf->category = WLAN_CATEGORY_TDLS;
 772                 tf->action_code = WLAN_TDLS_SETUP_RESPONSE;
 773
 774                 skb_put(skb, sizeof(tf->u.setup_resp));
 775                 tf->u.setup_resp.status_code = cpu_to_le16(status_code);
 776                 tf->u.setup_resp.dialog_token = dialog_token;
 777                 tf->u.setup_resp.capability =
 778                         cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
 779                                                                  status_code));
 780                 break;
 781         case WLAN_TDLS_SETUP_CONFIRM:
 782                 tf->category = WLAN_CATEGORY_TDLS;
 783                 tf->action_code = WLAN_TDLS_SETUP_CONFIRM;
 784
 785                 skb_put(skb, sizeof(tf->u.setup_cfm));
 786                 tf->u.setup_cfm.status_code = cpu_to_le16(status_code);
 787                 tf->u.setup_cfm.dialog_token = dialog_token;
 788                 break;
 789         case WLAN_TDLS_TEARDOWN:
 790                 tf->category = WLAN_CATEGORY_TDLS;
 791                 tf->action_code = WLAN_TDLS_TEARDOWN;
 792
 793                 skb_put(skb, sizeof(tf->u.teardown));
 794                 tf->u.teardown.reason_code = cpu_to_le16(status_code);
 795                 break;
 796         case WLAN_TDLS_DISCOVERY_REQUEST:
 797                 tf->category = WLAN_CATEGORY_TDLS;
 798                 tf->action_code = WLAN_TDLS_DISCOVERY_REQUEST;
 799
 800                 skb_put(skb, sizeof(tf->u.discover_req));
 801                 tf->u.discover_req.dialog_token = dialog_token;
 802                 break;
 803         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
 804                 tf->category = WLAN_CATEGORY_TDLS;
 805                 tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
 806
 807                 skb_put(skb, sizeof(tf->u.chan_switch_req));
 808                 break;
 809         case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
 810                 tf->category = WLAN_CATEGORY_TDLS;
 811                 tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
 812
 813                 skb_put(skb, sizeof(tf->u.chan_switch_resp));
 814                 tf->u.chan_switch_resp.status_code = cpu_to_le16(status_code);
 815                 break;
 816         default:
 817                 return -EINVAL;
 818         }
 819
 820         return 0;
 821 }
 822
 823 static int
 824 ieee80211_prep_tdls_direct(struct wiphy *wiphy, struct net_device *dev,
 825                            const u8 *peer, u8 action_code, u8 dialog_token,
 826                            u16 status_code, struct sk_buff *skb)
 827 {
 828         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 829         struct ieee80211_mgmt *mgmt;
 830
 831         mgmt = (void *)skb_put(skb, 24);
 832         memset(mgmt, 0, 24);
 833         memcpy(mgmt->da, peer, ETH_ALEN);
 834         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 835         memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
 836
 837         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 838                                           IEEE80211_STYPE_ACTION);
 839
 840         switch (action_code) {
 841         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 842                 skb_put(skb, 1 + sizeof(mgmt->u.action.u.tdls_discover_resp));
 843                 mgmt->u.action.category = WLAN_CATEGORY_PUBLIC;
 844                 mgmt->u.action.u.tdls_discover_resp.action_code =
 845                         WLAN_PUB_ACTION_TDLS_DISCOVER_RES;
 846                 mgmt->u.action.u.tdls_discover_resp.dialog_token =
 847                         dialog_token;
 848                 mgmt->u.action.u.tdls_discover_resp.capability =
 849                         cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
 850                                                                  status_code));
 851                 break;
 852         default:
 853                 return -EINVAL;
 854         }
 855
 856         return 0;
 857 }
 858
 859 static struct sk_buff *
 860 ieee80211_tdls_build_mgmt_packet_data(struct ieee80211_sub_if_data *sdata,
 861                                       const u8 *peer, u8 action_code,
 862                                       u8 dialog_token, u16 status_code,
 863                                       bool initiator, const u8 *extra_ies,
 864                                       size_t extra_ies_len, u8 oper_class,
 865                                       struct cfg80211_chan_def *chandef)
 866 {
 867         struct ieee80211_local *local = sdata->local;
 868         struct sk_buff *skb;
 869         int ret;
 870
 871         skb = netdev_alloc_skb(sdata->dev,
 872                                local->hw.extra_tx_headroom +
 873                                max(sizeof(struct ieee80211_mgmt),
 874                                    sizeof(struct ieee80211_tdls_data)) +
 875                                50 + /* supported rates */
 876                                10 + /* ext capab */
 877                                26 + /* max(WMM-info, WMM-param) */
 878                                2 + max(sizeof(struct ieee80211_ht_cap),
 879                                        sizeof(struct ieee80211_ht_operation)) +
 880                                2 + max(sizeof(struct ieee80211_vht_cap),
 881                                        sizeof(struct ieee80211_vht_operation)) +
 882                                50 + /* supported channels */
 883                                3 + /* 40/20 BSS coex */
 884                                4 + /* AID */
 885                                4 + /* oper classes */
 886                                extra_ies_len +
 887                                sizeof(struct ieee80211_tdls_lnkie));
 888         if (!skb)
 889                 return NULL;
 890
 891         skb_reserve(skb, local->hw.extra_tx_headroom);
 892
 893         switch (action_code) {
 894         case WLAN_TDLS_SETUP_REQUEST:
 895         case WLAN_TDLS_SETUP_RESPONSE:
 896         case WLAN_TDLS_SETUP_CONFIRM:
 897         case WLAN_TDLS_TEARDOWN:
 898         case WLAN_TDLS_DISCOVERY_REQUEST:
 899         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
 900         case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
 901                 ret = ieee80211_prep_tdls_encap_data(local->hw.wiphy,
 902                                                      sdata->dev, peer,
 903                                                      action_code, dialog_token,
 904                                                      status_code, skb);
 905                 break;
 906         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 907                 ret = ieee80211_prep_tdls_direct(local->hw.wiphy, sdata->dev,
 908                                                  peer, action_code,
 909                                                  dialog_token, status_code,
 910                                                  skb);
 911                 break;
 912         default:
 913                 ret = -ENOTSUPP;
 914                 break;
 915         }
 916
 917         if (ret < 0)
 918                 goto fail;
 919
 920         ieee80211_tdls_add_ies(sdata, skb, peer, action_code, status_code,
 921                                initiator, extra_ies, extra_ies_len, oper_class,
 922                                chandef);
 923         return skb;
 924
 925 fail:
 926         dev_kfree_skb(skb);
 927         return NULL;
 928 }
 929
 930 static int
 931 ieee80211_tdls_prep_mgmt_packet(struct wiphy *wiphy, struct net_device *dev,
 932                                 const u8 *peer, u8 action_code, u8 dialog_token,
 933                                 u16 status_code, u32 peer_capability,
 934                                 bool initiator, const u8 *extra_ies,
 935                                 size_t extra_ies_len, u8 oper_class,
 936                                 struct cfg80211_chan_def *chandef)
 937 {
 938         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 939         struct sk_buff *skb = NULL;
 940         struct sta_info *sta;
 941         u32 flags = 0;
 942         int ret = 0;
 943
 944         rcu_read_lock();
 945         sta = sta_info_get(sdata, peer);
 946
 947         /* infer the initiator if we can, to support old userspace */
 948         switch (action_code) {
 949         case WLAN_TDLS_SETUP_REQUEST:
 950                 if (sta) {
 951                         set_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
 952                         sta->sta.tdls_initiator = false;
 953                 }
 954                 /* fall-through */
 955         case WLAN_TDLS_SETUP_CONFIRM:
 956         case WLAN_TDLS_DISCOVERY_REQUEST:
 957                 initiator = true;
 958                 break;
 959         case WLAN_TDLS_SETUP_RESPONSE:
 960                 /*
 961                  * In some testing scenarios, we send a request and response.
 962                  * Make the last packet sent take effect for the initiator
 963                  * value.
 964                  */
 965                 if (sta) {
 966                         clear_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
 967                         sta->sta.tdls_initiator = true;
 968                 }
 969                 /* fall-through */
 970         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 971                 initiator = false;
 972                 break;
 973         case WLAN_TDLS_TEARDOWN:
 974         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
 975         case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
 976                 /* any value is ok */
 977                 break;
 978         default:
 979                 ret = -ENOTSUPP;
 980                 break;
 981         }
 982
 983         if (sta && test_sta_flag(sta, WLAN_STA_TDLS_INITIATOR))
 984                 initiator = true;
 985
 986         rcu_read_unlock();
 987         if (ret < 0)
 988                 goto fail;
 989
 990         skb = ieee80211_tdls_build_mgmt_packet_data(sdata, peer, action_code,
 991                                                     dialog_token, status_code,
 992                                                     initiator, extra_ies,
 993                                                     extra_ies_len, oper_class,
 994                                                     chandef);
 995         if (!skb) {
 996                 ret = -EINVAL;
 997                 goto fail;
 998         }
 999
1000         if (action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) {
1001                 ieee80211_tx_skb(sdata, skb);
1002                 return 0;
1003         }
1004
1005         /*
1006          * According to 802.11z: Setup req/resp are sent in AC_BK, otherwise
1007          * we should default to AC_VI.
1008          */
1009         switch (action_code) {
1010         case WLAN_TDLS_SETUP_REQUEST:
1011         case WLAN_TDLS_SETUP_RESPONSE:
1012                 skb_set_queue_mapping(skb, IEEE80211_AC_BK);
1013                 skb->priority = 2;
1014                 break;
1015         default:
1016                 skb_set_queue_mapping(skb, IEEE80211_AC_VI);
1017                 skb->priority = 5;
1018                 break;
1019         }
1020
1021         /*
1022          * Set the WLAN_TDLS_TEARDOWN flag to indicate a teardown in progress.
1023          * Later, if no ACK is returned from peer, we will re-send the teardown
1024          * packet through the AP.
1025          */
1026         if ((action_code == WLAN_TDLS_TEARDOWN) &&
1027             ieee80211_hw_check(&sdata->local->hw, REPORTS_TX_ACK_STATUS)) {
1028                 bool try_resend; /* Should we keep skb for possible resend */
1029
1030                 /* If not sending directly to peer - no point in keeping skb */
1031                 rcu_read_lock();
1032                 sta = sta_info_get(sdata, peer);
1033                 try_resend = sta && test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1034                 rcu_read_unlock();
1035
1036                 spin_lock_bh(&sdata->u.mgd.teardown_lock);
1037                 if (try_resend && !sdata->u.mgd.teardown_skb) {
1038                         /* Mark it as requiring TX status callback  */
1039                         flags |= IEEE80211_TX_CTL_REQ_TX_STATUS |
1040                                  IEEE80211_TX_INTFL_MLME_CONN_TX;
1041
1042                         /*
1043                          * skb is copied since mac80211 will later set
1044                          * properties that might not be the same as the AP,
1045                          * such as encryption, QoS, addresses, etc.
1046                          *
1047                          * No problem if skb_copy() fails, so no need to check.
1048                          */
1049                         sdata->u.mgd.teardown_skb = skb_copy(skb, GFP_ATOMIC);
1050                         sdata->u.mgd.orig_teardown_skb = skb;
1051                 }
1052                 spin_unlock_bh(&sdata->u.mgd.teardown_lock);
1053         }
1054
1055         /* disable bottom halves when entering the Tx path */
1056         local_bh_disable();
1057         __ieee80211_subif_start_xmit(skb, dev, flags);
1058         local_bh_enable();
1059
1060         return ret;
1061
1062 fail:
1063         dev_kfree_skb(skb);
1064         return ret;
1065 }
1066
1067 static int
1068 ieee80211_tdls_mgmt_setup(struct wiphy *wiphy, struct net_device *dev,
1069                           const u8 *peer, u8 action_code, u8 dialog_token,
1070                           u16 status_code, u32 peer_capability, bool initiator,
1071                           const u8 *extra_ies, size_t extra_ies_len)
1072 {
1073         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1074         struct ieee80211_local *local = sdata->local;
1075         enum ieee80211_smps_mode smps_mode = sdata->u.mgd.driver_smps_mode;
1076         int ret;
1077
1078         /* don't support setup with forced SMPS mode that's not off */
1079         if (smps_mode != IEEE80211_SMPS_AUTOMATIC &&
1080             smps_mode != IEEE80211_SMPS_OFF) {
1081                 tdls_dbg(sdata, "Aborting TDLS setup due to SMPS mode %d\n",
1082                          smps_mode);
1083                 return -ENOTSUPP;
1084         }
1085
1086         mutex_lock(&local->mtx);
1087
1088         /* we don't support concurrent TDLS peer setups */
1089         if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer) &&
1090             !ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
1091                 ret = -EBUSY;
1092                 goto out_unlock;
1093         }
1094
1095         /*
1096          * make sure we have a STA representing the peer so we drop or buffer
1097          * non-TDLS-setup frames to the peer. We can't send other packets
1098          * during setup through the AP path.
1099          * Allow error packets to be sent - sometimes we don't even add a STA
1100          * before failing the setup.
1101          */
1102         if (status_code == 0) {
1103                 rcu_read_lock();
1104                 if (!sta_info_get(sdata, peer)) {
1105                         rcu_read_unlock();
1106                         ret = -ENOLINK;
1107                         goto out_unlock;
1108                 }
1109                 rcu_read_unlock();
1110         }
1111
1112         ieee80211_flush_queues(local, sdata, false);
1113         memcpy(sdata->u.mgd.tdls_peer, peer, ETH_ALEN);
1114         mutex_unlock(&local->mtx);
1115
1116         /* we cannot take the mutex while preparing the setup packet */
1117         ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
1118                                               dialog_token, status_code,
1119                                               peer_capability, initiator,
1120                                               extra_ies, extra_ies_len, 0,
1121                                               NULL);
1122         if (ret < 0) {
1123                 mutex_lock(&local->mtx);
1124                 eth_zero_addr(sdata->u.mgd.tdls_peer);
1125                 mutex_unlock(&local->mtx);
1126                 return ret;
1127         }
1128
1129         ieee80211_queue_delayed_work(&sdata->local->hw,
1130                                      &sdata->u.mgd.tdls_peer_del_work,
1131                                      TDLS_PEER_SETUP_TIMEOUT);
1132         return 0;
1133
1134 out_unlock:
1135         mutex_unlock(&local->mtx);
1136         return ret;
1137 }
1138
1139 static int
1140 ieee80211_tdls_mgmt_teardown(struct wiphy *wiphy, struct net_device *dev,
1141                              const u8 *peer, u8 action_code, u8 dialog_token,
1142                              u16 status_code, u32 peer_capability,
1143                              bool initiator, const u8 *extra_ies,
1144                              size_t extra_ies_len)
1145 {
1146         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1147         struct ieee80211_local *local = sdata->local;
1148         struct sta_info *sta;
1149         int ret;
1150
1151         /*
1152          * No packets can be transmitted to the peer via the AP during setup -
1153          * the STA is set as a TDLS peer, but is not authorized.
1154          * During teardown, we prevent direct transmissions by stopping the
1155          * queues and flushing all direct packets.
1156          */
1157         ieee80211_stop_vif_queues(local, sdata,
1158                                   IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
1159         ieee80211_flush_queues(local, sdata, false);
1160
1161         ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
1162                                               dialog_token, status_code,
1163                                               peer_capability, initiator,
1164                                               extra_ies, extra_ies_len, 0,
1165                                               NULL);
1166         if (ret < 0)
1167                 sdata_err(sdata, "Failed sending TDLS teardown packet %d\n",
1168                           ret);
1169
1170         /*
1171          * Remove the STA AUTH flag to force further traffic through the AP. If
1172          * the STA was unreachable, it was already removed.
1173          */
1174         rcu_read_lock();
1175         sta = sta_info_get(sdata, peer);
1176         if (sta)
1177                 clear_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1178         rcu_read_unlock();
1179
1180         ieee80211_wake_vif_queues(local, sdata,
1181                                   IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
1182
1183         return 0;
1184 }
1185
1186 int ieee80211_tdls_mgmt(struct wiphy *wiphy, struct net_device *dev,
1187                         const u8 *peer, u8 action_code, u8 dialog_token,
1188                         u16 status_code, u32 peer_capability,
1189                         bool initiator, const u8 *extra_ies,
1190                         size_t extra_ies_len)
1191 {
1192         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1193         int ret;
1194
1195         if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
1196                 return -ENOTSUPP;
1197
1198         /* make sure we are in managed mode, and associated */
1199         if (sdata->vif.type != NL80211_IFTYPE_STATION ||
1200             !sdata->u.mgd.associated)
1201                 return -EINVAL;
1202
1203         switch (action_code) {
1204         case WLAN_TDLS_SETUP_REQUEST:
1205         case WLAN_TDLS_SETUP_RESPONSE:
1206                 ret = ieee80211_tdls_mgmt_setup(wiphy, dev, peer, action_code,
1207                                                 dialog_token, status_code,
1208                                                 peer_capability, initiator,
1209                                                 extra_ies, extra_ies_len);
1210                 break;
1211         case WLAN_TDLS_TEARDOWN:
1212                 ret = ieee80211_tdls_mgmt_teardown(wiphy, dev, peer,
1213                                                    action_code, dialog_token,
1214                                                    status_code,
1215                                                    peer_capability, initiator,
1216                                                    extra_ies, extra_ies_len);
1217                 break;
1218         case WLAN_TDLS_DISCOVERY_REQUEST:
1219                 /*
1220                  * Protect the discovery so we can hear the TDLS discovery
1221                  * response frame. It is transmitted directly and not buffered
1222                  * by the AP.
1223                  */
1224                 drv_mgd_protect_tdls_discover(sdata->local, sdata);
1225                 /* fall-through */
1226         case WLAN_TDLS_SETUP_CONFIRM:
1227         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
1228                 /* no special handling */
1229                 ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer,
1230                                                       action_code,
1231                                                       dialog_token,
1232                                                       status_code,
1233                                                       peer_capability,
1234                                                       initiator, extra_ies,
1235                                                       extra_ies_len, 0, NULL);
1236                 break;
1237         default:
1238                 ret = -EOPNOTSUPP;
1239                 break;
1240         }
1241
1242         tdls_dbg(sdata, "TDLS mgmt action %d peer %pM status %d\n",
1243                  action_code, peer, ret);
1244         return ret;
1245 }
1246
1247 static void iee80211_tdls_recalc_chanctx(struct ieee80211_sub_if_data *sdata,
1248                                          struct sta_info *sta)
1249 {
1250         struct ieee80211_local *local = sdata->local;
1251         struct ieee80211_chanctx_conf *conf;
1252         struct ieee80211_chanctx *ctx;
1253         enum nl80211_chan_width width;
1254         struct ieee80211_supported_band *sband;
1255
1256         mutex_lock(&local->chanctx_mtx);
1257         conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
1258                                          lockdep_is_held(&local->chanctx_mtx));
1259         if (conf) {
1260                 width = conf->def.width;
1261                 sband = local->hw.wiphy->bands[conf->def.chan->band];
1262                 ctx = container_of(conf, struct ieee80211_chanctx, conf);
1263                 ieee80211_recalc_chanctx_chantype(local, ctx);
1264
1265                 /* if width changed and a peer is given, update its BW */
1266                 if (width != conf->def.width && sta &&
1267                     test_sta_flag(sta, WLAN_STA_TDLS_WIDER_BW)) {
1268                         enum ieee80211_sta_rx_bandwidth bw;
1269
1270                         bw = ieee80211_chan_width_to_rx_bw(conf->def.width);
1271                         bw = min(bw, ieee80211_sta_cap_rx_bw(sta));
1272                         if (bw != sta->sta.bandwidth) {
1273                                 sta->sta.bandwidth = bw;
1274                                 rate_control_rate_update(local, sband, sta,
1275                                                          IEEE80211_RC_BW_CHANGED);
1276                                 /*
1277                                  * if a TDLS peer BW was updated, we need to
1278                                  * recalc the chandef width again, to get the
1279                                  * correct chanctx min_def
1280                                  */
1281                                 ieee80211_recalc_chanctx_chantype(local, ctx);
1282                         }
1283                 }
1284
1285         }
1286         mutex_unlock(&local->chanctx_mtx);
1287 }
1288
1289 static int iee80211_tdls_have_ht_peers(struct ieee80211_sub_if_data *sdata)
1290 {
1291         struct sta_info *sta;
1292         bool result = false;
1293
1294         rcu_read_lock();
1295         list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
1296                 if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
1297                     !test_sta_flag(sta, WLAN_STA_AUTHORIZED) ||
1298                     !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH) ||
1299                     !sta->sta.ht_cap.ht_supported)
1300                         continue;
1301                 result = true;
1302                 break;
1303         }
1304         rcu_read_unlock();
1305
1306         return result;
1307 }
1308
1309 static void
1310 iee80211_tdls_recalc_ht_protection(struct ieee80211_sub_if_data *sdata,
1311                                    struct sta_info *sta)
1312 {
1313         struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
1314         bool tdls_ht;
1315         u16 protection = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED |
1316                          IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT |
1317                          IEEE80211_HT_OP_MODE_NON_HT_STA_PRSNT;
1318         u16 opmode;
1319
1320         /* Nothing to do if the BSS connection uses HT */
1321         if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HT))
1322                 return;
1323
1324         tdls_ht = (sta && sta->sta.ht_cap.ht_supported) ||
1325                   iee80211_tdls_have_ht_peers(sdata);
1326
1327         opmode = sdata->vif.bss_conf.ht_operation_mode;
1328
1329         if (tdls_ht)
1330                 opmode |= protection;
1331         else
1332                 opmode &= ~protection;
1333
1334         if (opmode == sdata->vif.bss_conf.ht_operation_mode)
1335                 return;
1336
1337         sdata->vif.bss_conf.ht_operation_mode = opmode;
1338         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_HT);
1339 }
1340
1341 int ieee80211_tdls_oper(struct wiphy *wiphy, struct net_device *dev,
1342                         const u8 *peer, enum nl80211_tdls_operation oper)
1343 {
1344         struct sta_info *sta;
1345         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1346         struct ieee80211_local *local = sdata->local;
1347         int ret;
1348
1349         if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
1350                 return -ENOTSUPP;
1351
1352         if (sdata->vif.type != NL80211_IFTYPE_STATION)
1353                 return -EINVAL;
1354
1355         switch (oper) {
1356         case NL80211_TDLS_ENABLE_LINK:
1357         case NL80211_TDLS_DISABLE_LINK:
1358                 break;
1359         case NL80211_TDLS_TEARDOWN:
1360         case NL80211_TDLS_SETUP:
1361         case NL80211_TDLS_DISCOVERY_REQ:
1362                 /* We don't support in-driver setup/teardown/discovery */
1363                 return -ENOTSUPP;
1364         }
1365
1366         /* protect possible bss_conf changes and avoid concurrency in
1367          * ieee80211_bss_info_change_notify()
1368          */
1369         sdata_lock(sdata);
1370         mutex_lock(&local->mtx);
1371         tdls_dbg(sdata, "TDLS oper %d peer %pM\n", oper, peer);
1372
1373         switch (oper) {
1374         case NL80211_TDLS_ENABLE_LINK:
1375                 if (sdata->vif.csa_active) {
1376                         tdls_dbg(sdata, "TDLS: disallow link during CSA\n");
1377                         ret = -EBUSY;
1378                         break;
1379                 }
1380
1381                 mutex_lock(&local->sta_mtx);
1382                 sta = sta_info_get(sdata, peer);
1383                 if (!sta) {
1384                         mutex_unlock(&local->sta_mtx);
1385                         ret = -ENOLINK;
1386                         break;
1387                 }
1388
1389                 iee80211_tdls_recalc_chanctx(sdata, sta);
1390                 iee80211_tdls_recalc_ht_protection(sdata, sta);
1391
1392                 set_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1393                 mutex_unlock(&local->sta_mtx);
1394
1395                 WARN_ON_ONCE(is_zero_ether_addr(sdata->u.mgd.tdls_peer) ||
1396                              !ether_addr_equal(sdata->u.mgd.tdls_peer, peer));
1397                 ret = 0;
1398                 break;
1399         case NL80211_TDLS_DISABLE_LINK:
1400                 /*
1401                  * The teardown message in ieee80211_tdls_mgmt_teardown() was
1402                  * created while the queues were stopped, so it might still be
1403                  * pending. Before flushing the queues we need to be sure the
1404                  * message is handled by the tasklet handling pending messages,
1405                  * otherwise we might start destroying the station before
1406                  * sending the teardown packet.
1407                  * Note that this only forces the tasklet to flush pendings -
1408                  * not to stop the tasklet from rescheduling itself.
1409                  */
1410                 tasklet_kill(&local->tx_pending_tasklet);
1411                 /* flush a potentially queued teardown packet */
1412                 ieee80211_flush_queues(local, sdata, false);
1413
1414                 ret = sta_info_destroy_addr(sdata, peer);
1415
1416                 mutex_lock(&local->sta_mtx);
1417                 iee80211_tdls_recalc_ht_protection(sdata, NULL);
1418                 mutex_unlock(&local->sta_mtx);
1419
1420                 iee80211_tdls_recalc_chanctx(sdata, NULL);
1421                 break;
1422         default:
1423                 ret = -ENOTSUPP;
1424                 break;
1425         }
1426
1427         if (ret == 0 && ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
1428                 cancel_delayed_work(&sdata->u.mgd.tdls_peer_del_work);
1429                 eth_zero_addr(sdata->u.mgd.tdls_peer);
1430         }
1431
1432         if (ret == 0)
1433                 ieee80211_queue_work(&sdata->local->hw,
1434                                      &sdata->u.mgd.request_smps_work);
1435
1436         mutex_unlock(&local->mtx);
1437         sdata_unlock(sdata);
1438         return ret;
1439 }
1440
1441 void ieee80211_tdls_oper_request(struct ieee80211_vif *vif, const u8 *peer,
1442                                  enum nl80211_tdls_operation oper,
1443                                  u16 reason_code, gfp_t gfp)
1444 {
1445         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1446
1447         if (vif->type != NL80211_IFTYPE_STATION || !vif->bss_conf.assoc) {
1448                 sdata_err(sdata, "Discarding TDLS oper %d - not STA or disconnected\n",
1449                           oper);
1450                 return;
1451         }
1452
1453         cfg80211_tdls_oper_request(sdata->dev, peer, oper, reason_code, gfp);
1454 }
1455 EXPORT_SYMBOL(ieee80211_tdls_oper_request);
1456
1457 static void
1458 iee80211_tdls_add_ch_switch_timing(u8 *buf, u16 switch_time, u16 switch_timeout)
1459 {
1460         struct ieee80211_ch_switch_timing *ch_sw;
1461
1462         *buf++ = WLAN_EID_CHAN_SWITCH_TIMING;
1463         *buf++ = sizeof(struct ieee80211_ch_switch_timing);
1464
1465         ch_sw = (void *)buf;
1466         ch_sw->switch_time = cpu_to_le16(switch_time);
1467         ch_sw->switch_timeout = cpu_to_le16(switch_timeout);
1468 }
1469
1470 /* find switch timing IE in SKB ready for Tx */
1471 static const u8 *ieee80211_tdls_find_sw_timing_ie(struct sk_buff *skb)
1472 {
1473         struct ieee80211_tdls_data *tf;
1474         const u8 *ie_start;
1475
1476         /*
1477          * Get the offset for the new location of the switch timing IE.
1478          * The SKB network header will now point to the "payload_type"
1479          * element of the TDLS data frame struct.
1480          */
1481         tf = container_of(skb->data + skb_network_offset(skb),
1482                           struct ieee80211_tdls_data, payload_type);
1483         ie_start = tf->u.chan_switch_req.variable;
1484         return cfg80211_find_ie(WLAN_EID_CHAN_SWITCH_TIMING, ie_start,
1485                                 skb->len - (ie_start - skb->data));
1486 }
1487
1488 static struct sk_buff *
1489 ieee80211_tdls_ch_sw_tmpl_get(struct sta_info *sta, u8 oper_class,
1490                               struct cfg80211_chan_def *chandef,
1491                               u32 *ch_sw_tm_ie_offset)
1492 {
1493         struct ieee80211_sub_if_data *sdata = sta->sdata;
1494         u8 extra_ies[2 + sizeof(struct ieee80211_sec_chan_offs_ie) +
1495                      2 + sizeof(struct ieee80211_ch_switch_timing)];
1496         int extra_ies_len = 2 + sizeof(struct ieee80211_ch_switch_timing);
1497         u8 *pos = extra_ies;
1498         struct sk_buff *skb;
1499
1500         /*
1501          * if chandef points to a wide channel add a Secondary-Channel
1502          * Offset information element
1503          */
1504         if (chandef->width == NL80211_CHAN_WIDTH_40) {
1505                 struct ieee80211_sec_chan_offs_ie *sec_chan_ie;
1506                 bool ht40plus;
1507
1508                 *pos++ = WLAN_EID_SECONDARY_CHANNEL_OFFSET;
1509                 *pos++ = sizeof(*sec_chan_ie);
1510                 sec_chan_ie = (void *)pos;
1511
1512                 ht40plus = cfg80211_get_chandef_type(chandef) ==
1513                                                         NL80211_CHAN_HT40PLUS;
1514                 sec_chan_ie->sec_chan_offs = ht40plus ?
1515                                              IEEE80211_HT_PARAM_CHA_SEC_ABOVE :
1516                                              IEEE80211_HT_PARAM_CHA_SEC_BELOW;
1517                 pos += sizeof(*sec_chan_ie);
1518
1519                 extra_ies_len += 2 + sizeof(struct ieee80211_sec_chan_offs_ie);
1520         }
1521
1522         /* just set the values to 0, this is a template */
1523         iee80211_tdls_add_ch_switch_timing(pos, 0, 0);
1524
1525         skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1526                                               WLAN_TDLS_CHANNEL_SWITCH_REQUEST,
1527                                               0, 0, !sta->sta.tdls_initiator,
1528                                               extra_ies, extra_ies_len,
1529                                               oper_class, chandef);
1530         if (!skb)
1531                 return NULL;
1532
1533         skb = ieee80211_build_data_template(sdata, skb, 0);
1534         if (IS_ERR(skb)) {
1535                 tdls_dbg(sdata, "Failed building TDLS channel switch frame\n");
1536                 return NULL;
1537         }
1538
1539         if (ch_sw_tm_ie_offset) {
1540                 const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1541
1542                 if (!tm_ie) {
1543                         tdls_dbg(sdata, "No switch timing IE in TDLS switch\n");
1544                         dev_kfree_skb_any(skb);
1545                         return NULL;
1546                 }
1547
1548                 *ch_sw_tm_ie_offset = tm_ie - skb->data;
1549         }
1550
1551         tdls_dbg(sdata,
1552                  "TDLS channel switch request template for %pM ch %d width %d\n",
1553                  sta->sta.addr, chandef->chan->center_freq, chandef->width);
1554         return skb;
1555 }
1556
1557 int
1558 ieee80211_tdls_channel_switch(struct wiphy *wiphy, struct net_device *dev,
1559                               const u8 *addr, u8 oper_class,
1560                               struct cfg80211_chan_def *chandef)
1561 {
1562         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1563         struct ieee80211_local *local = sdata->local;
1564         struct sta_info *sta;
1565         struct sk_buff *skb = NULL;
1566         u32 ch_sw_tm_ie;
1567         int ret;
1568
1569         mutex_lock(&local->sta_mtx);
1570         sta = sta_info_get(sdata, addr);
1571         if (!sta) {
1572                 tdls_dbg(sdata,
1573                          "Invalid TDLS peer %pM for channel switch request\n",
1574                          addr);
1575                 ret = -ENOENT;
1576                 goto out;
1577         }
1578
1579         if (!test_sta_flag(sta, WLAN_STA_TDLS_CHAN_SWITCH)) {
1580                 tdls_dbg(sdata, "TDLS channel switch unsupported by %pM\n",
1581                          addr);
1582                 ret = -ENOTSUPP;
1583                 goto out;
1584         }
1585
1586         skb = ieee80211_tdls_ch_sw_tmpl_get(sta, oper_class, chandef,
1587                                             &ch_sw_tm_ie);
1588         if (!skb) {
1589                 ret = -ENOENT;
1590                 goto out;
1591         }
1592
1593         ret = drv_tdls_channel_switch(local, sdata, &sta->sta, oper_class,
1594                                       chandef, skb, ch_sw_tm_ie);
1595         if (!ret)
1596                 set_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1597
1598 out:
1599         mutex_unlock(&local->sta_mtx);
1600         dev_kfree_skb_any(skb);
1601         return ret;
1602 }
1603
1604 void
1605 ieee80211_tdls_cancel_channel_switch(struct wiphy *wiphy,
1606                                      struct net_device *dev,
1607                                      const u8 *addr)
1608 {
1609         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1610         struct ieee80211_local *local = sdata->local;
1611         struct sta_info *sta;
1612
1613         mutex_lock(&local->sta_mtx);
1614         sta = sta_info_get(sdata, addr);
1615         if (!sta) {
1616                 tdls_dbg(sdata,
1617                          "Invalid TDLS peer %pM for channel switch cancel\n",
1618                          addr);
1619                 goto out;
1620         }
1621
1622         if (!test_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL)) {
1623                 tdls_dbg(sdata, "TDLS channel switch not initiated by %pM\n",
1624                          addr);
1625                 goto out;
1626         }
1627
1628         drv_tdls_cancel_channel_switch(local, sdata, &sta->sta);
1629         clear_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1630
1631 out:
1632         mutex_unlock(&local->sta_mtx);
1633 }
1634
1635 static struct sk_buff *
1636 ieee80211_tdls_ch_sw_resp_tmpl_get(struct sta_info *sta,
1637                                    u32 *ch_sw_tm_ie_offset)
1638 {
1639         struct ieee80211_sub_if_data *sdata = sta->sdata;
1640         struct sk_buff *skb;
1641         u8 extra_ies[2 + sizeof(struct ieee80211_ch_switch_timing)];
1642
1643         /* initial timing are always zero in the template */
1644         iee80211_tdls_add_ch_switch_timing(extra_ies, 0, 0);
1645
1646         skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1647                                         WLAN_TDLS_CHANNEL_SWITCH_RESPONSE,
1648                                         0, 0, !sta->sta.tdls_initiator,
1649                                         extra_ies, sizeof(extra_ies), 0, NULL);
1650         if (!skb)
1651                 return NULL;
1652
1653         skb = ieee80211_build_data_template(sdata, skb, 0);
1654         if (IS_ERR(skb)) {
1655                 tdls_dbg(sdata,
1656                          "Failed building TDLS channel switch resp frame\n");
1657                 return NULL;
1658         }
1659
1660         if (ch_sw_tm_ie_offset) {
1661                 const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1662
1663                 if (!tm_ie) {
1664                         tdls_dbg(sdata,
1665                                  "No switch timing IE in TDLS switch resp\n");
1666                         dev_kfree_skb_any(skb);
1667                         return NULL;
1668                 }
1669
1670                 *ch_sw_tm_ie_offset = tm_ie - skb->data;
1671         }
1672
1673         tdls_dbg(sdata, "TDLS get channel switch response template for %pM\n",
1674                  sta->sta.addr);
1675         return skb;
1676 }
1677
1678 static int
1679 ieee80211_process_tdls_channel_switch_resp(struct ieee80211_sub_if_data *sdata,
1680                                            struct sk_buff *skb)
1681 {
1682         struct ieee80211_local *local = sdata->local;
1683         struct ieee802_11_elems elems;
1684         struct sta_info *sta;
1685         struct ieee80211_tdls_data *tf = (void *)skb->data;
1686         bool local_initiator;
1687         struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1688         int baselen = offsetof(typeof(*tf), u.chan_switch_resp.variable);
1689         struct ieee80211_tdls_ch_sw_params params = {};
1690         int ret;
1691
1692         params.action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
1693         params.timestamp = rx_status->device_timestamp;
1694
1695         if (skb->len < baselen) {
1696                 tdls_dbg(sdata, "TDLS channel switch resp too short: %d\n",
1697                          skb->len);
1698                 return -EINVAL;
1699         }
1700
1701         mutex_lock(&local->sta_mtx);
1702         sta = sta_info_get(sdata, tf->sa);
1703         if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1704                 tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1705                          tf->sa);
1706                 ret = -EINVAL;
1707                 goto out;
1708         }
1709
1710         params.sta = &sta->sta;
1711         params.status = le16_to_cpu(tf->u.chan_switch_resp.status_code);
1712         if (params.status != 0) {
1713                 ret = 0;
1714                 goto call_drv;
1715         }
1716
1717         ieee802_11_parse_elems(tf->u.chan_switch_resp.variable,
1718                                skb->len - baselen, false, &elems);
1719         if (elems.parse_error) {
1720                 tdls_dbg(sdata, "Invalid IEs in TDLS channel switch resp\n");
1721                 ret = -EINVAL;
1722                 goto out;
1723         }
1724
1725         if (!elems.ch_sw_timing || !elems.lnk_id) {
1726                 tdls_dbg(sdata, "TDLS channel switch resp - missing IEs\n");
1727                 ret = -EINVAL;
1728                 goto out;
1729         }
1730
1731         /* validate the initiator is set correctly */
1732         local_initiator =
1733                 !memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1734         if (local_initiator == sta->sta.tdls_initiator) {
1735                 tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1736                 ret = -EINVAL;
1737                 goto out;
1738         }
1739
1740         params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1741         params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1742
1743         params.tmpl_skb =
1744                 ieee80211_tdls_ch_sw_resp_tmpl_get(sta, &params.ch_sw_tm_ie);
1745         if (!params.tmpl_skb) {
1746                 ret = -ENOENT;
1747                 goto out;
1748         }
1749
1750 call_drv:
1751         drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1752
1753         tdls_dbg(sdata,
1754                  "TDLS channel switch response received from %pM status %d\n",
1755                  tf->sa, params.status);
1756
1757 out:
1758         mutex_unlock(&local->sta_mtx);
1759         dev_kfree_skb_any(params.tmpl_skb);
1760         return ret;
1761 }
1762
1763 static int
1764 ieee80211_process_tdls_channel_switch_req(struct ieee80211_sub_if_data *sdata,
1765                                           struct sk_buff *skb)
1766 {
1767         struct ieee80211_local *local = sdata->local;
1768         struct ieee802_11_elems elems;
1769         struct cfg80211_chan_def chandef;
1770         struct ieee80211_channel *chan;
1771         enum nl80211_channel_type chan_type;
1772         int freq;
1773         u8 target_channel, oper_class;
1774         bool local_initiator;
1775         struct sta_info *sta;
1776         enum nl80211_band band;
1777         struct ieee80211_tdls_data *tf = (void *)skb->data;
1778         struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1779         int baselen = offsetof(typeof(*tf), u.chan_switch_req.variable);
1780         struct ieee80211_tdls_ch_sw_params params = {};
1781         int ret = 0;
1782
1783         params.action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
1784         params.timestamp = rx_status->device_timestamp;
1785
1786         if (skb->len < baselen) {
1787                 tdls_dbg(sdata, "TDLS channel switch req too short: %d\n",
1788                          skb->len);
1789                 return -EINVAL;
1790         }
1791
1792         target_channel = tf->u.chan_switch_req.target_channel;
1793         oper_class = tf->u.chan_switch_req.oper_class;
1794
1795         /*
1796          * We can't easily infer the channel band. The operating class is
1797          * ambiguous - there are multiple tables (US/Europe/JP/Global). The
1798          * solution here is to treat channels with number >14 as 5GHz ones,
1799          * and specifically check for the (oper_class, channel) combinations
1800          * where this doesn't hold. These are thankfully unique according to
1801          * IEEE802.11-2012.
1802          * We consider only the 2GHz and 5GHz bands and 20MHz+ channels as
1803          * valid here.
1804          */
1805         if ((oper_class == 112 || oper_class == 2 || oper_class == 3 ||
1806              oper_class == 4 || oper_class == 5 || oper_class == 6) &&
1807              target_channel < 14)
1808                 band = NL80211_BAND_5GHZ;
1809         else
1810                 band = target_channel < 14 ? NL80211_BAND_2GHZ :
1811                                              NL80211_BAND_5GHZ;
1812
1813         freq = ieee80211_channel_to_frequency(target_channel, band);
1814         if (freq == 0) {
1815                 tdls_dbg(sdata, "Invalid channel in TDLS chan switch: %d\n",
1816                          target_channel);
1817                 return -EINVAL;
1818         }
1819
1820         chan = ieee80211_get_channel(sdata->local->hw.wiphy, freq);
1821         if (!chan) {
1822                 tdls_dbg(sdata,
1823                          "Unsupported channel for TDLS chan switch: %d\n",
1824                          target_channel);
1825                 return -EINVAL;
1826         }
1827
1828         ieee802_11_parse_elems(tf->u.chan_switch_req.variable,
1829                                skb->len - baselen, false, &elems);
1830         if (elems.parse_error) {
1831                 tdls_dbg(sdata, "Invalid IEs in TDLS channel switch req\n");
1832                 return -EINVAL;
1833         }
1834
1835         if (!elems.ch_sw_timing || !elems.lnk_id) {
1836                 tdls_dbg(sdata, "TDLS channel switch req - missing IEs\n");
1837                 return -EINVAL;
1838         }
1839
1840         if (!elems.sec_chan_offs) {
1841                 chan_type = NL80211_CHAN_HT20;
1842         } else {
1843                 switch (elems.sec_chan_offs->sec_chan_offs) {
1844                 case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
1845                         chan_type = NL80211_CHAN_HT40PLUS;
1846                         break;
1847                 case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
1848                         chan_type = NL80211_CHAN_HT40MINUS;
1849                         break;
1850                 default:
1851                         chan_type = NL80211_CHAN_HT20;
1852                         break;
1853                 }
1854         }
1855
1856         cfg80211_chandef_create(&chandef, chan, chan_type);
1857
1858         /* we will be active on the TDLS link */
1859         if (!cfg80211_reg_can_beacon_relax(sdata->local->hw.wiphy, &chandef,
1860                                            sdata->wdev.iftype)) {
1861                 tdls_dbg(sdata, "TDLS chan switch to forbidden channel\n");
1862                 return -EINVAL;
1863         }
1864
1865         mutex_lock(&local->sta_mtx);
1866         sta = sta_info_get(sdata, tf->sa);
1867         if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1868                 tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1869                          tf->sa);
1870                 ret = -EINVAL;
1871                 goto out;
1872         }
1873
1874         params.sta = &sta->sta;
1875
1876         /* validate the initiator is set correctly */
1877         local_initiator =
1878                 !memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1879         if (local_initiator == sta->sta.tdls_initiator) {
1880                 tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1881                 ret = -EINVAL;
1882                 goto out;
1883         }
1884
1885         /* peer should have known better */
1886         if (!sta->sta.ht_cap.ht_supported && elems.sec_chan_offs &&
1887             elems.sec_chan_offs->sec_chan_offs) {
1888                 tdls_dbg(sdata, "TDLS chan switch - wide chan unsupported\n");
1889                 ret = -ENOTSUPP;
1890                 goto out;
1891         }
1892
1893         params.chandef = &chandef;
1894         params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1895         params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1896
1897         params.tmpl_skb =
1898                 ieee80211_tdls_ch_sw_resp_tmpl_get(sta,
1899                                                    &params.ch_sw_tm_ie);
1900         if (!params.tmpl_skb) {
1901                 ret = -ENOENT;
1902                 goto out;
1903         }
1904
1905         drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1906
1907         tdls_dbg(sdata,
1908                  "TDLS ch switch request received from %pM ch %d width %d\n",
1909                  tf->sa, params.chandef->chan->center_freq,
1910                  params.chandef->width);
1911 out:
1912         mutex_unlock(&local->sta_mtx);
1913         dev_kfree_skb_any(params.tmpl_skb);
1914         return ret;
1915 }
1916
1917 static void
1918 ieee80211_process_tdls_channel_switch(struct ieee80211_sub_if_data *sdata,
1919                                       struct sk_buff *skb)
1920 {
1921         struct ieee80211_tdls_data *tf = (void *)skb->data;
1922         struct wiphy *wiphy = sdata->local->hw.wiphy;
1923
1924         ASSERT_RTNL();
1925
1926         /* make sure the driver supports it */
1927         if (!(wiphy->features & NL80211_FEATURE_TDLS_CHANNEL_SWITCH))
1928                 return;
1929
1930         /* we want to access the entire packet */
1931         if (skb_linearize(skb))
1932                 return;
1933         /*
1934          * The packet/size was already validated by mac80211 Rx path, only look
1935          * at the action type.
1936          */
1937         switch (tf->action_code) {
1938         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
1939                 ieee80211_process_tdls_channel_switch_req(sdata, skb);
1940                 break;
1941         case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
1942                 ieee80211_process_tdls_channel_switch_resp(sdata, skb);
1943                 break;
1944         default:
1945                 WARN_ON_ONCE(1);
1946                 return;
1947         }
1948 }
1949
1950 void ieee80211_teardown_tdls_peers(struct ieee80211_sub_if_data *sdata)
1951 {
1952         struct sta_info *sta;
1953         u16 reason = WLAN_REASON_TDLS_TEARDOWN_UNSPECIFIED;
1954
1955         rcu_read_lock();
1956         list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
1957                 if (!sta->sta.tdls || sta->sdata != sdata || !sta->uploaded ||
1958                     !test_sta_flag(sta, WLAN_STA_AUTHORIZED))
1959                         continue;
1960
1961                 ieee80211_tdls_oper_request(&sdata->vif, sta->sta.addr,
1962                                             NL80211_TDLS_TEARDOWN, reason,
1963                                             GFP_ATOMIC);
1964         }
1965         rcu_read_unlock();
1966 }
1967
1968 void ieee80211_tdls_chsw_work(struct work_struct *wk)
1969 {
1970         struct ieee80211_local *local =
1971                 container_of(wk, struct ieee80211_local, tdls_chsw_work);
1972         struct ieee80211_sub_if_data *sdata;
1973         struct sk_buff *skb;
1974         struct ieee80211_tdls_data *tf;
1975
1976         rtnl_lock();
1977         while ((skb = skb_dequeue(&local->skb_queue_tdls_chsw))) {
1978                 tf = (struct ieee80211_tdls_data *)skb->data;
1979                 list_for_each_entry(sdata, &local->interfaces, list) {
1980                         if (!ieee80211_sdata_running(sdata) ||
1981                             sdata->vif.type != NL80211_IFTYPE_STATION ||
1982                             !ether_addr_equal(tf->da, sdata->vif.addr))
1983                                 continue;
1984
1985                         ieee80211_process_tdls_channel_switch(sdata, skb);
1986                         break;
1987                 }
1988
1989                 kfree_skb(skb);
1990         }
1991         rtnl_unlock();
1992 }