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  *
   8  * This file is GPLv2 as found in COPYING.
   9  */
  10
  11 #include <linux/ieee80211.h>
  12 #include <linux/log2.h>
  13 #include <net/cfg80211.h>
  14 #include "ieee80211_i.h"
  15 #include "driver-ops.h"
  16
  17 /* give usermode some time for retries in setting up the TDLS session */
  18 #define TDLS_PEER_SETUP_TIMEOUT (15 * HZ)
  19
  20 void ieee80211_tdls_peer_del_work(struct work_struct *wk)
  21 {
  22         struct ieee80211_sub_if_data *sdata;
  23         struct ieee80211_local *local;
  24
  25         sdata = container_of(wk, struct ieee80211_sub_if_data,
  26                              u.mgd.tdls_peer_del_work.work);
  27         local = sdata->local;
  28
  29         mutex_lock(&local->mtx);
  30         if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer)) {
  31                 tdls_dbg(sdata, "TDLS del peer %pM\n", sdata->u.mgd.tdls_peer);
  32                 sta_info_destroy_addr(sdata, sdata->u.mgd.tdls_peer);
  33                 eth_zero_addr(sdata->u.mgd.tdls_peer);
  34         }
  35         mutex_unlock(&local->mtx);
  36 }
  37
  38 static void ieee80211_tdls_add_ext_capab(struct ieee80211_local *local,
  39                                          struct sk_buff *skb)
  40 {
  41         u8 *pos = (void *)skb_put(skb, 7);
  42         bool chan_switch = local->hw.wiphy->features &
  43                            NL80211_FEATURE_TDLS_CHANNEL_SWITCH;
  44
  45         *pos++ = WLAN_EID_EXT_CAPABILITY;
  46         *pos++ = 5; /* len */
  47         *pos++ = 0x0;
  48         *pos++ = 0x0;
  49         *pos++ = 0x0;
  50         *pos++ = chan_switch ? WLAN_EXT_CAPA4_TDLS_CHAN_SWITCH : 0;
  51         *pos++ = WLAN_EXT_CAPA5_TDLS_ENABLED;
  52 }
  53
  54 static u8
  55 ieee80211_tdls_add_subband(struct ieee80211_sub_if_data *sdata,
  56                            struct sk_buff *skb, u16 start, u16 end,
  57                            u16 spacing)
  58 {
  59         u8 subband_cnt = 0, ch_cnt = 0;
  60         struct ieee80211_channel *ch;
  61         struct cfg80211_chan_def chandef;
  62         int i, subband_start;
  63
  64         for (i = start; i <= end; i += spacing) {
  65                 if (!ch_cnt)
  66                         subband_start = i;
  67
  68                 ch = ieee80211_get_channel(sdata->local->hw.wiphy, i);
  69                 if (ch) {
  70                         /* we will be active on the channel */
  71                         u32 flags = IEEE80211_CHAN_DISABLED |
  72                                     IEEE80211_CHAN_NO_IR;
  73                         cfg80211_chandef_create(&chandef, ch,
  74                                                 NL80211_CHAN_HT20);
  75                         if (cfg80211_chandef_usable(sdata->local->hw.wiphy,
  76                                                     &chandef, flags)) {
  77                                 ch_cnt++;
  78                                 continue;
  79                         }
  80                 }
  81
  82                 if (ch_cnt) {
  83                         u8 *pos = skb_put(skb, 2);
  84                         *pos++ = ieee80211_frequency_to_channel(subband_start);
  85                         *pos++ = ch_cnt;
  86
  87                         subband_cnt++;
  88                         ch_cnt = 0;
  89                 }
  90         }
  91
  92         return subband_cnt;
  93 }
  94
  95 static void
  96 ieee80211_tdls_add_supp_channels(struct ieee80211_sub_if_data *sdata,
  97                                  struct sk_buff *skb)
  98 {
  99         /*
 100          * Add possible channels for TDLS. These are channels that are allowed
 101          * to be active.
 102          */
 103         u8 subband_cnt;
 104         u8 *pos = skb_put(skb, 2);
 105
 106         *pos++ = WLAN_EID_SUPPORTED_CHANNELS;
 107
 108         /*
 109          * 5GHz and 2GHz channels numbers can overlap. Ignore this for now, as
 110          * this doesn't happen in real world scenarios.
 111          */
 112
 113         /* 2GHz, with 5MHz spacing */
 114         subband_cnt = ieee80211_tdls_add_subband(sdata, skb, 2412, 2472, 5);
 115
 116         /* 5GHz, with 20MHz spacing */
 117         subband_cnt += ieee80211_tdls_add_subband(sdata, skb, 5000, 5825, 20);
 118
 119         /* length */
 120         *pos = 2 * subband_cnt;
 121 }
 122
 123 static void ieee80211_tdls_add_bss_coex_ie(struct sk_buff *skb)
 124 {
 125         u8 *pos = (void *)skb_put(skb, 3);
 126
 127         *pos++ = WLAN_EID_BSS_COEX_2040;
 128         *pos++ = 1; /* len */
 129
 130         *pos++ = WLAN_BSS_COEX_INFORMATION_REQUEST;
 131 }
 132
 133 static u16 ieee80211_get_tdls_sta_capab(struct ieee80211_sub_if_data *sdata,
 134                                         u16 status_code)
 135 {
 136         struct ieee80211_local *local = sdata->local;
 137         u16 capab;
 138
 139         /* The capability will be 0 when sending a failure code */
 140         if (status_code != 0)
 141                 return 0;
 142
 143         capab = 0;
 144         if (ieee80211_get_sdata_band(sdata) != IEEE80211_BAND_2GHZ)
 145                 return capab;
 146
 147         if (!(local->hw.flags & IEEE80211_HW_2GHZ_SHORT_SLOT_INCAPABLE))
 148                 capab |= WLAN_CAPABILITY_SHORT_SLOT_TIME;
 149         if (!(local->hw.flags & IEEE80211_HW_2GHZ_SHORT_PREAMBLE_INCAPABLE))
 150                 capab |= WLAN_CAPABILITY_SHORT_PREAMBLE;
 151
 152         return capab;
 153 }
 154
 155 static void ieee80211_tdls_add_link_ie(struct ieee80211_sub_if_data *sdata,
 156                                        struct sk_buff *skb, const u8 *peer,
 157                                        bool initiator)
 158 {
 159         struct ieee80211_tdls_lnkie *lnkid;
 160         const u8 *init_addr, *rsp_addr;
 161
 162         if (initiator) {
 163                 init_addr = sdata->vif.addr;
 164                 rsp_addr = peer;
 165         } else {
 166                 init_addr = peer;
 167                 rsp_addr = sdata->vif.addr;
 168         }
 169
 170         lnkid = (void *)skb_put(skb, sizeof(struct ieee80211_tdls_lnkie));
 171
 172         lnkid->ie_type = WLAN_EID_LINK_ID;
 173         lnkid->ie_len = sizeof(struct ieee80211_tdls_lnkie) - 2;
 174
 175         memcpy(lnkid->bssid, sdata->u.mgd.bssid, ETH_ALEN);
 176         memcpy(lnkid->init_sta, init_addr, ETH_ALEN);
 177         memcpy(lnkid->resp_sta, rsp_addr, ETH_ALEN);
 178 }
 179
 180 /* translate numbering in the WMM parameter IE to the mac80211 notation */
 181 static enum ieee80211_ac_numbers ieee80211_ac_from_wmm(int ac)
 182 {
 183         switch (ac) {
 184         default:
 185                 WARN_ON_ONCE(1);
 186         case 0:
 187                 return IEEE80211_AC_BE;
 188         case 1:
 189                 return IEEE80211_AC_BK;
 190         case 2:
 191                 return IEEE80211_AC_VI;
 192         case 3:
 193                 return IEEE80211_AC_VO;
 194         }
 195 }
 196
 197 static u8 ieee80211_wmm_aci_aifsn(int aifsn, bool acm, int aci)
 198 {
 199         u8 ret;
 200
 201         ret = aifsn & 0x0f;
 202         if (acm)
 203                 ret |= 0x10;
 204         ret |= (aci << 5) & 0x60;
 205         return ret;
 206 }
 207
 208 static u8 ieee80211_wmm_ecw(u16 cw_min, u16 cw_max)
 209 {
 210         return ((ilog2(cw_min + 1) << 0x0) & 0x0f) |
 211                ((ilog2(cw_max + 1) << 0x4) & 0xf0);
 212 }
 213
 214 static void ieee80211_tdls_add_wmm_param_ie(struct ieee80211_sub_if_data *sdata,
 215                                             struct sk_buff *skb)
 216 {
 217         struct ieee80211_wmm_param_ie *wmm;
 218         struct ieee80211_tx_queue_params *txq;
 219         int i;
 220
 221         wmm = (void *)skb_put(skb, sizeof(*wmm));
 222         memset(wmm, 0, sizeof(*wmm));
 223
 224         wmm->element_id = WLAN_EID_VENDOR_SPECIFIC;
 225         wmm->len = sizeof(*wmm) - 2;
 226
 227         wmm->oui[0] = 0x00; /* Microsoft OUI 00:50:F2 */
 228         wmm->oui[1] = 0x50;
 229         wmm->oui[2] = 0xf2;
 230         wmm->oui_type = 2; /* WME */
 231         wmm->oui_subtype = 1; /* WME param */
 232         wmm->version = 1; /* WME ver */
 233         wmm->qos_info = 0; /* U-APSD not in use */
 234
 235         /*
 236          * Use the EDCA parameters defined for the BSS, or default if the AP
 237          * doesn't support it, as mandated by 802.11-2012 section 10.22.4
 238          */
 239         for (i = 0; i < IEEE80211_NUM_ACS; i++) {
 240                 txq = &sdata->tx_conf[ieee80211_ac_from_wmm(i)];
 241                 wmm->ac[i].aci_aifsn = ieee80211_wmm_aci_aifsn(txq->aifs,
 242                                                                txq->acm, i);
 243                 wmm->ac[i].cw = ieee80211_wmm_ecw(txq->cw_min, txq->cw_max);
 244                 wmm->ac[i].txop_limit = cpu_to_le16(txq->txop);
 245         }
 246 }
 247
 248 static void
 249 ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
 250                                    struct sk_buff *skb, const u8 *peer,
 251                                    u8 action_code, bool initiator,
 252                                    const u8 *extra_ies, size_t extra_ies_len)
 253 {
 254         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
 255         struct ieee80211_local *local = sdata->local;
 256         struct ieee80211_supported_band *sband;
 257         struct ieee80211_sta_ht_cap ht_cap;
 258         struct sta_info *sta = NULL;
 259         size_t offset = 0, noffset;
 260         u8 *pos;
 261
 262         rcu_read_lock();
 263
 264         /* we should have the peer STA if we're already responding */
 265         if (action_code == WLAN_TDLS_SETUP_RESPONSE) {
 266                 sta = sta_info_get(sdata, peer);
 267                 if (WARN_ON_ONCE(!sta)) {
 268                         rcu_read_unlock();
 269                         return;
 270                 }
 271         }
 272
 273         ieee80211_add_srates_ie(sdata, skb, false, band);
 274         ieee80211_add_ext_srates_ie(sdata, skb, false, band);
 275         ieee80211_tdls_add_supp_channels(sdata, skb);
 276
 277         /* add any custom IEs that go before Extended Capabilities */
 278         if (extra_ies_len) {
 279                 static const u8 before_ext_cap[] = {
 280                         WLAN_EID_SUPP_RATES,
 281                         WLAN_EID_COUNTRY,
 282                         WLAN_EID_EXT_SUPP_RATES,
 283                         WLAN_EID_SUPPORTED_CHANNELS,
 284                         WLAN_EID_RSN,
 285                 };
 286                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 287                                              before_ext_cap,
 288                                              ARRAY_SIZE(before_ext_cap),
 289                                              offset);
 290                 pos = skb_put(skb, noffset - offset);
 291                 memcpy(pos, extra_ies + offset, noffset - offset);
 292                 offset = noffset;
 293         }
 294
 295         ieee80211_tdls_add_ext_capab(local, skb);
 296
 297         /* add the QoS element if we support it */
 298         if (local->hw.queues >= IEEE80211_NUM_ACS &&
 299             action_code != WLAN_PUB_ACTION_TDLS_DISCOVER_RES)
 300                 ieee80211_add_wmm_info_ie(skb_put(skb, 9), 0); /* no U-APSD */
 301
 302         /* add any custom IEs that go before HT capabilities */
 303         if (extra_ies_len) {
 304                 static const u8 before_ht_cap[] = {
 305                         WLAN_EID_SUPP_RATES,
 306                         WLAN_EID_COUNTRY,
 307                         WLAN_EID_EXT_SUPP_RATES,
 308                         WLAN_EID_SUPPORTED_CHANNELS,
 309                         WLAN_EID_RSN,
 310                         WLAN_EID_EXT_CAPABILITY,
 311                         WLAN_EID_QOS_CAPA,
 312                         WLAN_EID_FAST_BSS_TRANSITION,
 313                         WLAN_EID_TIMEOUT_INTERVAL,
 314                         WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
 315                 };
 316                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 317                                              before_ht_cap,
 318                                              ARRAY_SIZE(before_ht_cap),
 319                                              offset);
 320                 pos = skb_put(skb, noffset - offset);
 321                 memcpy(pos, extra_ies + offset, noffset - offset);
 322                 offset = noffset;
 323         }
 324
 325         /*
 326          * with TDLS we can switch channels, and HT-caps are not necessarily
 327          * the same on all bands. The specification limits the setup to a
 328          * single HT-cap, so use the current band for now.
 329          */
 330         sband = local->hw.wiphy->bands[band];
 331         memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
 332         if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
 333              action_code == WLAN_TDLS_SETUP_RESPONSE) &&
 334             ht_cap.ht_supported && (!sta || sta->sta.ht_cap.ht_supported)) {
 335                 if (action_code == WLAN_TDLS_SETUP_REQUEST) {
 336                         ieee80211_apply_htcap_overrides(sdata, &ht_cap);
 337
 338                         /* disable SMPS in TDLS initiator */
 339                         ht_cap.cap |= (WLAN_HT_CAP_SM_PS_DISABLED
 340                                        << IEEE80211_HT_CAP_SM_PS_SHIFT);
 341                 } else {
 342                         /* disable SMPS in TDLS responder */
 343                         sta->sta.ht_cap.cap |=
 344                                 (WLAN_HT_CAP_SM_PS_DISABLED
 345                                  << IEEE80211_HT_CAP_SM_PS_SHIFT);
 346
 347                         /* the peer caps are already intersected with our own */
 348                         memcpy(&ht_cap, &sta->sta.ht_cap, sizeof(ht_cap));
 349                 }
 350
 351                 pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
 352                 ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
 353         }
 354
 355         rcu_read_unlock();
 356
 357         if (ht_cap.ht_supported &&
 358             (ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40))
 359                 ieee80211_tdls_add_bss_coex_ie(skb);
 360
 361         /* add any remaining IEs */
 362         if (extra_ies_len) {
 363                 noffset = extra_ies_len;
 364                 pos = skb_put(skb, noffset - offset);
 365                 memcpy(pos, extra_ies + offset, noffset - offset);
 366         }
 367
 368         ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 369 }
 370
 371 static void
 372 ieee80211_tdls_add_setup_cfm_ies(struct ieee80211_sub_if_data *sdata,
 373                                  struct sk_buff *skb, const u8 *peer,
 374                                  bool initiator, const u8 *extra_ies,
 375                                  size_t extra_ies_len)
 376 {
 377         struct ieee80211_local *local = sdata->local;
 378         struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
 379         size_t offset = 0, noffset;
 380         struct sta_info *sta, *ap_sta;
 381         u8 *pos;
 382
 383         rcu_read_lock();
 384
 385         sta = sta_info_get(sdata, peer);
 386         ap_sta = sta_info_get(sdata, ifmgd->bssid);
 387         if (WARN_ON_ONCE(!sta || !ap_sta)) {
 388                 rcu_read_unlock();
 389                 return;
 390         }
 391
 392         /* add any custom IEs that go before the QoS IE */
 393         if (extra_ies_len) {
 394                 static const u8 before_qos[] = {
 395                         WLAN_EID_RSN,
 396                 };
 397                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 398                                              before_qos,
 399                                              ARRAY_SIZE(before_qos),
 400                                              offset);
 401                 pos = skb_put(skb, noffset - offset);
 402                 memcpy(pos, extra_ies + offset, noffset - offset);
 403                 offset = noffset;
 404         }
 405
 406         /* add the QoS param IE if both the peer and we support it */
 407         if (local->hw.queues >= IEEE80211_NUM_ACS && sta->sta.wme)
 408                 ieee80211_tdls_add_wmm_param_ie(sdata, skb);
 409
 410         /* add any custom IEs that go before HT operation */
 411         if (extra_ies_len) {
 412                 static const u8 before_ht_op[] = {
 413                         WLAN_EID_RSN,
 414                         WLAN_EID_QOS_CAPA,
 415                         WLAN_EID_FAST_BSS_TRANSITION,
 416                         WLAN_EID_TIMEOUT_INTERVAL,
 417                 };
 418                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 419                                              before_ht_op,
 420                                              ARRAY_SIZE(before_ht_op),
 421                                              offset);
 422                 pos = skb_put(skb, noffset - offset);
 423                 memcpy(pos, extra_ies + offset, noffset - offset);
 424                 offset = noffset;
 425         }
 426
 427         /* if HT support is only added in TDLS, we need an HT-operation IE */
 428         if (!ap_sta->sta.ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
 429                 struct ieee80211_chanctx_conf *chanctx_conf =
 430                                 rcu_dereference(sdata->vif.chanctx_conf);
 431                 if (!WARN_ON(!chanctx_conf)) {
 432                         pos = skb_put(skb, 2 +
 433                                       sizeof(struct ieee80211_ht_operation));
 434                         /* send an empty HT operation IE */
 435                         ieee80211_ie_build_ht_oper(pos, &sta->sta.ht_cap,
 436                                                    &chanctx_conf->def, 0);
 437                 }
 438         }
 439
 440         rcu_read_unlock();
 441
 442         /* add any remaining IEs */
 443         if (extra_ies_len) {
 444                 noffset = extra_ies_len;
 445                 pos = skb_put(skb, noffset - offset);
 446                 memcpy(pos, extra_ies + offset, noffset - offset);
 447         }
 448
 449         ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 450 }
 451
 452 static void
 453 ieee80211_tdls_add_chan_switch_req_ies(struct ieee80211_sub_if_data *sdata,
 454                                        struct sk_buff *skb, const u8 *peer,
 455                                        bool initiator, const u8 *extra_ies,
 456                                        size_t extra_ies_len, u8 oper_class,
 457                                        struct cfg80211_chan_def *chandef)
 458 {
 459         struct ieee80211_tdls_data *tf;
 460         size_t offset = 0, noffset;
 461         u8 *pos;
 462
 463         if (WARN_ON_ONCE(!chandef))
 464                 return;
 465
 466         tf = (void *)skb->data;
 467         tf->u.chan_switch_req.target_channel =
 468                 ieee80211_frequency_to_channel(chandef->chan->center_freq);
 469         tf->u.chan_switch_req.oper_class = oper_class;
 470
 471         if (extra_ies_len) {
 472                 static const u8 before_lnkie[] = {
 473                         WLAN_EID_SECONDARY_CHANNEL_OFFSET,
 474                 };
 475                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 476                                              before_lnkie,
 477                                              ARRAY_SIZE(before_lnkie),
 478                                              offset);
 479                 pos = skb_put(skb, noffset - offset);
 480                 memcpy(pos, extra_ies + offset, noffset - offset);
 481                 offset = noffset;
 482         }
 483
 484         ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 485
 486         /* add any remaining IEs */
 487         if (extra_ies_len) {
 488                 noffset = extra_ies_len;
 489                 pos = skb_put(skb, noffset - offset);
 490                 memcpy(pos, extra_ies + offset, noffset - offset);
 491         }
 492 }
 493
 494 static void ieee80211_tdls_add_ies(struct ieee80211_sub_if_data *sdata,
 495                                    struct sk_buff *skb, const u8 *peer,
 496                                    u8 action_code, u16 status_code,
 497                                    bool initiator, const u8 *extra_ies,
 498                                    size_t extra_ies_len, u8 oper_class,
 499                                    struct cfg80211_chan_def *chandef)
 500 {
 501         switch (action_code) {
 502         case WLAN_TDLS_SETUP_REQUEST:
 503         case WLAN_TDLS_SETUP_RESPONSE:
 504         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 505                 if (status_code == 0)
 506                         ieee80211_tdls_add_setup_start_ies(sdata, skb, peer,
 507                                                            action_code,
 508                                                            initiator,
 509                                                            extra_ies,
 510                                                            extra_ies_len);
 511                 break;
 512         case WLAN_TDLS_SETUP_CONFIRM:
 513                 if (status_code == 0)
 514                         ieee80211_tdls_add_setup_cfm_ies(sdata, skb, peer,
 515                                                          initiator, extra_ies,
 516                                                          extra_ies_len);
 517                 break;
 518         case WLAN_TDLS_TEARDOWN:
 519         case WLAN_TDLS_DISCOVERY_REQUEST:
 520                 if (extra_ies_len)
 521                         memcpy(skb_put(skb, extra_ies_len), extra_ies,
 522                                extra_ies_len);
 523                 if (status_code == 0 || action_code == WLAN_TDLS_TEARDOWN)
 524                         ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 525                 break;
 526         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
 527                 ieee80211_tdls_add_chan_switch_req_ies(sdata, skb, peer,
 528                                                        initiator, extra_ies,
 529                                                        extra_ies_len,
 530                                                        oper_class, chandef);
 531                 break;
 532         }
 533
 534 }
 535
 536 static int
 537 ieee80211_prep_tdls_encap_data(struct wiphy *wiphy, struct net_device *dev,
 538                                const u8 *peer, u8 action_code, u8 dialog_token,
 539                                u16 status_code, struct sk_buff *skb)
 540 {
 541         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 542         struct ieee80211_tdls_data *tf;
 543
 544         tf = (void *)skb_put(skb, offsetof(struct ieee80211_tdls_data, u));
 545
 546         memcpy(tf->da, peer, ETH_ALEN);
 547         memcpy(tf->sa, sdata->vif.addr, ETH_ALEN);
 548         tf->ether_type = cpu_to_be16(ETH_P_TDLS);
 549         tf->payload_type = WLAN_TDLS_SNAP_RFTYPE;
 550
 551         /* network header is after the ethernet header */
 552         skb_set_network_header(skb, ETH_HLEN);
 553
 554         switch (action_code) {
 555         case WLAN_TDLS_SETUP_REQUEST:
 556                 tf->category = WLAN_CATEGORY_TDLS;
 557                 tf->action_code = WLAN_TDLS_SETUP_REQUEST;
 558
 559                 skb_put(skb, sizeof(tf->u.setup_req));
 560                 tf->u.setup_req.dialog_token = dialog_token;
 561                 tf->u.setup_req.capability =
 562                         cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
 563                                                                  status_code));
 564                 break;
 565         case WLAN_TDLS_SETUP_RESPONSE:
 566                 tf->category = WLAN_CATEGORY_TDLS;
 567                 tf->action_code = WLAN_TDLS_SETUP_RESPONSE;
 568
 569                 skb_put(skb, sizeof(tf->u.setup_resp));
 570                 tf->u.setup_resp.status_code = cpu_to_le16(status_code);
 571                 tf->u.setup_resp.dialog_token = dialog_token;
 572                 tf->u.setup_resp.capability =
 573                         cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
 574                                                                  status_code));
 575                 break;
 576         case WLAN_TDLS_SETUP_CONFIRM:
 577                 tf->category = WLAN_CATEGORY_TDLS;
 578                 tf->action_code = WLAN_TDLS_SETUP_CONFIRM;
 579
 580                 skb_put(skb, sizeof(tf->u.setup_cfm));
 581                 tf->u.setup_cfm.status_code = cpu_to_le16(status_code);
 582                 tf->u.setup_cfm.dialog_token = dialog_token;
 583                 break;
 584         case WLAN_TDLS_TEARDOWN:
 585                 tf->category = WLAN_CATEGORY_TDLS;
 586                 tf->action_code = WLAN_TDLS_TEARDOWN;
 587
 588                 skb_put(skb, sizeof(tf->u.teardown));
 589                 tf->u.teardown.reason_code = cpu_to_le16(status_code);
 590                 break;
 591         case WLAN_TDLS_DISCOVERY_REQUEST:
 592                 tf->category = WLAN_CATEGORY_TDLS;
 593                 tf->action_code = WLAN_TDLS_DISCOVERY_REQUEST;
 594
 595                 skb_put(skb, sizeof(tf->u.discover_req));
 596                 tf->u.discover_req.dialog_token = dialog_token;
 597                 break;
 598         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
 599                 tf->category = WLAN_CATEGORY_TDLS;
 600                 tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
 601
 602                 skb_put(skb, sizeof(tf->u.chan_switch_req));
 603                 break;
 604         default:
 605                 return -EINVAL;
 606         }
 607
 608         return 0;
 609 }
 610
 611 static int
 612 ieee80211_prep_tdls_direct(struct wiphy *wiphy, struct net_device *dev,
 613                            const u8 *peer, u8 action_code, u8 dialog_token,
 614                            u16 status_code, struct sk_buff *skb)
 615 {
 616         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 617         struct ieee80211_mgmt *mgmt;
 618
 619         mgmt = (void *)skb_put(skb, 24);
 620         memset(mgmt, 0, 24);
 621         memcpy(mgmt->da, peer, ETH_ALEN);
 622         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 623         memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
 624
 625         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 626                                           IEEE80211_STYPE_ACTION);
 627
 628         switch (action_code) {
 629         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 630                 skb_put(skb, 1 + sizeof(mgmt->u.action.u.tdls_discover_resp));
 631                 mgmt->u.action.category = WLAN_CATEGORY_PUBLIC;
 632                 mgmt->u.action.u.tdls_discover_resp.action_code =
 633                         WLAN_PUB_ACTION_TDLS_DISCOVER_RES;
 634                 mgmt->u.action.u.tdls_discover_resp.dialog_token =
 635                         dialog_token;
 636                 mgmt->u.action.u.tdls_discover_resp.capability =
 637                         cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
 638                                                                  status_code));
 639                 break;
 640         default:
 641                 return -EINVAL;
 642         }
 643
 644         return 0;
 645 }
 646
 647 static struct sk_buff *
 648 ieee80211_tdls_build_mgmt_packet_data(struct ieee80211_sub_if_data *sdata,
 649                                       const u8 *peer, u8 action_code,
 650                                       u8 dialog_token, u16 status_code,
 651                                       bool initiator, const u8 *extra_ies,
 652                                       size_t extra_ies_len, u8 oper_class,
 653                                       struct cfg80211_chan_def *chandef)
 654 {
 655         struct ieee80211_local *local = sdata->local;
 656         struct sk_buff *skb;
 657         int ret;
 658
 659         skb = netdev_alloc_skb(sdata->dev,
 660                                local->hw.extra_tx_headroom +
 661                                max(sizeof(struct ieee80211_mgmt),
 662                                    sizeof(struct ieee80211_tdls_data)) +
 663                                50 + /* supported rates */
 664                                7 + /* ext capab */
 665                                26 + /* max(WMM-info, WMM-param) */
 666                                2 + max(sizeof(struct ieee80211_ht_cap),
 667                                        sizeof(struct ieee80211_ht_operation)) +
 668                                50 + /* supported channels */
 669                                3 + /* 40/20 BSS coex */
 670                                extra_ies_len +
 671                                sizeof(struct ieee80211_tdls_lnkie));
 672         if (!skb)
 673                 return NULL;
 674
 675         skb_reserve(skb, local->hw.extra_tx_headroom);
 676
 677         switch (action_code) {
 678         case WLAN_TDLS_SETUP_REQUEST:
 679         case WLAN_TDLS_SETUP_RESPONSE:
 680         case WLAN_TDLS_SETUP_CONFIRM:
 681         case WLAN_TDLS_TEARDOWN:
 682         case WLAN_TDLS_DISCOVERY_REQUEST:
 683         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
 684                 ret = ieee80211_prep_tdls_encap_data(local->hw.wiphy,
 685                                                      sdata->dev, peer,
 686                                                      action_code, dialog_token,
 687                                                      status_code, skb);
 688                 break;
 689         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 690                 ret = ieee80211_prep_tdls_direct(local->hw.wiphy, sdata->dev,
 691                                                  peer, action_code,
 692                                                  dialog_token, status_code,
 693                                                  skb);
 694                 break;
 695         default:
 696                 ret = -ENOTSUPP;
 697                 break;
 698         }
 699
 700         if (ret < 0)
 701                 goto fail;
 702
 703         ieee80211_tdls_add_ies(sdata, skb, peer, action_code, status_code,
 704                                initiator, extra_ies, extra_ies_len, oper_class,
 705                                chandef);
 706         return skb;
 707
 708 fail:
 709         dev_kfree_skb(skb);
 710         return NULL;
 711 }
 712
 713 static int
 714 ieee80211_tdls_prep_mgmt_packet(struct wiphy *wiphy, struct net_device *dev,
 715                                 const u8 *peer, u8 action_code, u8 dialog_token,
 716                                 u16 status_code, u32 peer_capability,
 717                                 bool initiator, const u8 *extra_ies,
 718                                 size_t extra_ies_len, u8 oper_class,
 719                                 struct cfg80211_chan_def *chandef)
 720 {
 721         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 722         struct sk_buff *skb = NULL;
 723         struct sta_info *sta;
 724         u32 flags = 0;
 725         int ret = 0;
 726
 727         rcu_read_lock();
 728         sta = sta_info_get(sdata, peer);
 729
 730         /* infer the initiator if we can, to support old userspace */
 731         switch (action_code) {
 732         case WLAN_TDLS_SETUP_REQUEST:
 733                 if (sta) {
 734                         set_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
 735                         sta->sta.tdls_initiator = false;
 736                 }
 737                 /* fall-through */
 738         case WLAN_TDLS_SETUP_CONFIRM:
 739         case WLAN_TDLS_DISCOVERY_REQUEST:
 740                 initiator = true;
 741                 break;
 742         case WLAN_TDLS_SETUP_RESPONSE:
 743                 /*
 744                  * In some testing scenarios, we send a request and response.
 745                  * Make the last packet sent take effect for the initiator
 746                  * value.
 747                  */
 748                 if (sta) {
 749                         clear_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
 750                         sta->sta.tdls_initiator = true;
 751                 }
 752                 /* fall-through */
 753         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 754                 initiator = false;
 755                 break;
 756         case WLAN_TDLS_TEARDOWN:
 757         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
 758                 /* any value is ok */
 759                 break;
 760         default:
 761                 ret = -ENOTSUPP;
 762                 break;
 763         }
 764
 765         if (sta && test_sta_flag(sta, WLAN_STA_TDLS_INITIATOR))
 766                 initiator = true;
 767
 768         rcu_read_unlock();
 769         if (ret < 0)
 770                 goto fail;
 771
 772         skb = ieee80211_tdls_build_mgmt_packet_data(sdata, peer, action_code,
 773                                                     dialog_token, status_code,
 774                                                     initiator, extra_ies,
 775                                                     extra_ies_len, oper_class,
 776                                                     chandef);
 777         if (!skb) {
 778                 ret = -EINVAL;
 779                 goto fail;
 780         }
 781
 782         if (action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) {
 783                 ieee80211_tx_skb(sdata, skb);
 784                 return 0;
 785         }
 786
 787         /*
 788          * According to 802.11z: Setup req/resp are sent in AC_BK, otherwise
 789          * we should default to AC_VI.
 790          */
 791         switch (action_code) {
 792         case WLAN_TDLS_SETUP_REQUEST:
 793         case WLAN_TDLS_SETUP_RESPONSE:
 794                 skb_set_queue_mapping(skb, IEEE80211_AC_BK);
 795                 skb->priority = 2;
 796                 break;
 797         default:
 798                 skb_set_queue_mapping(skb, IEEE80211_AC_VI);
 799                 skb->priority = 5;
 800                 break;
 801         }
 802
 803         /*
 804          * Set the WLAN_TDLS_TEARDOWN flag to indicate a teardown in progress.
 805          * Later, if no ACK is returned from peer, we will re-send the teardown
 806          * packet through the AP.
 807          */
 808         if ((action_code == WLAN_TDLS_TEARDOWN) &&
 809             (sdata->local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS)) {
 810                 struct sta_info *sta = NULL;
 811                 bool try_resend; /* Should we keep skb for possible resend */
 812
 813                 /* If not sending directly to peer - no point in keeping skb */
 814                 rcu_read_lock();
 815                 sta = sta_info_get(sdata, peer);
 816                 try_resend = sta && test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
 817                 rcu_read_unlock();
 818
 819                 spin_lock_bh(&sdata->u.mgd.teardown_lock);
 820                 if (try_resend && !sdata->u.mgd.teardown_skb) {
 821                         /* Mark it as requiring TX status callback  */
 822                         flags |= IEEE80211_TX_CTL_REQ_TX_STATUS |
 823                                  IEEE80211_TX_INTFL_MLME_CONN_TX;
 824
 825                         /*
 826                          * skb is copied since mac80211 will later set
 827                          * properties that might not be the same as the AP,
 828                          * such as encryption, QoS, addresses, etc.
 829                          *
 830                          * No problem if skb_copy() fails, so no need to check.
 831                          */
 832                         sdata->u.mgd.teardown_skb = skb_copy(skb, GFP_ATOMIC);
 833                         sdata->u.mgd.orig_teardown_skb = skb;
 834                 }
 835                 spin_unlock_bh(&sdata->u.mgd.teardown_lock);
 836         }
 837
 838         /* disable bottom halves when entering the Tx path */
 839         local_bh_disable();
 840         __ieee80211_subif_start_xmit(skb, dev, flags);
 841         local_bh_enable();
 842
 843         return ret;
 844
 845 fail:
 846         dev_kfree_skb(skb);
 847         return ret;
 848 }
 849
 850 static int
 851 ieee80211_tdls_mgmt_setup(struct wiphy *wiphy, struct net_device *dev,
 852                           const u8 *peer, u8 action_code, u8 dialog_token,
 853                           u16 status_code, u32 peer_capability, bool initiator,
 854                           const u8 *extra_ies, size_t extra_ies_len)
 855 {
 856         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 857         struct ieee80211_local *local = sdata->local;
 858         int ret;
 859
 860         mutex_lock(&local->mtx);
 861
 862         /* we don't support concurrent TDLS peer setups */
 863         if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer) &&
 864             !ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
 865                 ret = -EBUSY;
 866                 goto exit;
 867         }
 868
 869         /*
 870          * make sure we have a STA representing the peer so we drop or buffer
 871          * non-TDLS-setup frames to the peer. We can't send other packets
 872          * during setup through the AP path.
 873          * Allow error packets to be sent - sometimes we don't even add a STA
 874          * before failing the setup.
 875          */
 876         if (status_code == 0) {
 877                 rcu_read_lock();
 878                 if (!sta_info_get(sdata, peer)) {
 879                         rcu_read_unlock();
 880                         ret = -ENOLINK;
 881                         goto exit;
 882                 }
 883                 rcu_read_unlock();
 884         }
 885
 886         ieee80211_flush_queues(local, sdata);
 887
 888         ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
 889                                               dialog_token, status_code,
 890                                               peer_capability, initiator,
 891                                               extra_ies, extra_ies_len, 0,
 892                                               NULL);
 893         if (ret < 0)
 894                 goto exit;
 895
 896         memcpy(sdata->u.mgd.tdls_peer, peer, ETH_ALEN);
 897         ieee80211_queue_delayed_work(&sdata->local->hw,
 898                                      &sdata->u.mgd.tdls_peer_del_work,
 899                                      TDLS_PEER_SETUP_TIMEOUT);
 900
 901 exit:
 902         mutex_unlock(&local->mtx);
 903         return ret;
 904 }
 905
 906 static int
 907 ieee80211_tdls_mgmt_teardown(struct wiphy *wiphy, struct net_device *dev,
 908                              const u8 *peer, u8 action_code, u8 dialog_token,
 909                              u16 status_code, u32 peer_capability,
 910                              bool initiator, const u8 *extra_ies,
 911                              size_t extra_ies_len)
 912 {
 913         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 914         struct ieee80211_local *local = sdata->local;
 915         struct sta_info *sta;
 916         int ret;
 917
 918         /*
 919          * No packets can be transmitted to the peer via the AP during setup -
 920          * the STA is set as a TDLS peer, but is not authorized.
 921          * During teardown, we prevent direct transmissions by stopping the
 922          * queues and flushing all direct packets.
 923          */
 924         ieee80211_stop_vif_queues(local, sdata,
 925                                   IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
 926         ieee80211_flush_queues(local, sdata);
 927
 928         ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
 929                                               dialog_token, status_code,
 930                                               peer_capability, initiator,
 931                                               extra_ies, extra_ies_len, 0,
 932                                               NULL);
 933         if (ret < 0)
 934                 sdata_err(sdata, "Failed sending TDLS teardown packet %d\n",
 935                           ret);
 936
 937         /*
 938          * Remove the STA AUTH flag to force further traffic through the AP. If
 939          * the STA was unreachable, it was already removed.
 940          */
 941         rcu_read_lock();
 942         sta = sta_info_get(sdata, peer);
 943         if (sta)
 944                 clear_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
 945         rcu_read_unlock();
 946
 947         ieee80211_wake_vif_queues(local, sdata,
 948                                   IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
 949
 950         return 0;
 951 }
 952
 953 int ieee80211_tdls_mgmt(struct wiphy *wiphy, struct net_device *dev,
 954                         const u8 *peer, u8 action_code, u8 dialog_token,
 955                         u16 status_code, u32 peer_capability,
 956                         bool initiator, const u8 *extra_ies,
 957                         size_t extra_ies_len)
 958 {
 959         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 960         int ret;
 961
 962         if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
 963                 return -ENOTSUPP;
 964
 965         /* make sure we are in managed mode, and associated */
 966         if (sdata->vif.type != NL80211_IFTYPE_STATION ||
 967             !sdata->u.mgd.associated)
 968                 return -EINVAL;
 969
 970         switch (action_code) {
 971         case WLAN_TDLS_SETUP_REQUEST:
 972         case WLAN_TDLS_SETUP_RESPONSE:
 973                 ret = ieee80211_tdls_mgmt_setup(wiphy, dev, peer, action_code,
 974                                                 dialog_token, status_code,
 975                                                 peer_capability, initiator,
 976                                                 extra_ies, extra_ies_len);
 977                 break;
 978         case WLAN_TDLS_TEARDOWN:
 979                 ret = ieee80211_tdls_mgmt_teardown(wiphy, dev, peer,
 980                                                    action_code, dialog_token,
 981                                                    status_code,
 982                                                    peer_capability, initiator,
 983                                                    extra_ies, extra_ies_len);
 984                 break;
 985         case WLAN_TDLS_DISCOVERY_REQUEST:
 986                 /*
 987                  * Protect the discovery so we can hear the TDLS discovery
 988                  * response frame. It is transmitted directly and not buffered
 989                  * by the AP.
 990                  */
 991                 drv_mgd_protect_tdls_discover(sdata->local, sdata);
 992                 /* fall-through */
 993         case WLAN_TDLS_SETUP_CONFIRM:
 994         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 995                 /* no special handling */
 996                 ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer,
 997                                                       action_code,
 998                                                       dialog_token,
 999                                                       status_code,
1000                                                       peer_capability,
1001                                                       initiator, extra_ies,
1002                                                       extra_ies_len, 0, NULL);
1003                 break;
1004         default:
1005                 ret = -EOPNOTSUPP;
1006                 break;
1007         }
1008
1009         tdls_dbg(sdata, "TDLS mgmt action %d peer %pM status %d\n",
1010                  action_code, peer, ret);
1011         return ret;
1012 }
1013
1014 int ieee80211_tdls_oper(struct wiphy *wiphy, struct net_device *dev,
1015                         const u8 *peer, enum nl80211_tdls_operation oper)
1016 {
1017         struct sta_info *sta;
1018         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1019         struct ieee80211_local *local = sdata->local;
1020         int ret;
1021
1022         if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
1023                 return -ENOTSUPP;
1024
1025         if (sdata->vif.type != NL80211_IFTYPE_STATION)
1026                 return -EINVAL;
1027
1028         switch (oper) {
1029         case NL80211_TDLS_ENABLE_LINK:
1030         case NL80211_TDLS_DISABLE_LINK:
1031                 break;
1032         case NL80211_TDLS_TEARDOWN:
1033         case NL80211_TDLS_SETUP:
1034         case NL80211_TDLS_DISCOVERY_REQ:
1035                 /* We don't support in-driver setup/teardown/discovery */
1036                 return -ENOTSUPP;
1037         }
1038
1039         mutex_lock(&local->mtx);
1040         tdls_dbg(sdata, "TDLS oper %d peer %pM\n", oper, peer);
1041
1042         switch (oper) {
1043         case NL80211_TDLS_ENABLE_LINK:
1044                 rcu_read_lock();
1045                 sta = sta_info_get(sdata, peer);
1046                 if (!sta) {
1047                         rcu_read_unlock();
1048                         ret = -ENOLINK;
1049                         break;
1050                 }
1051
1052                 set_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1053                 rcu_read_unlock();
1054
1055                 WARN_ON_ONCE(is_zero_ether_addr(sdata->u.mgd.tdls_peer) ||
1056                              !ether_addr_equal(sdata->u.mgd.tdls_peer, peer));
1057                 ret = 0;
1058                 break;
1059         case NL80211_TDLS_DISABLE_LINK:
1060                 /*
1061                  * The teardown message in ieee80211_tdls_mgmt_teardown() was
1062                  * created while the queues were stopped, so it might still be
1063                  * pending. Before flushing the queues we need to be sure the
1064                  * message is handled by the tasklet handling pending messages,
1065                  * otherwise we might start destroying the station before
1066                  * sending the teardown packet.
1067                  * Note that this only forces the tasklet to flush pendings -
1068                  * not to stop the tasklet from rescheduling itself.
1069                  */
1070                 tasklet_kill(&local->tx_pending_tasklet);
1071                 /* flush a potentially queued teardown packet */
1072                 ieee80211_flush_queues(local, sdata);
1073
1074                 ret = sta_info_destroy_addr(sdata, peer);
1075                 break;
1076         default:
1077                 ret = -ENOTSUPP;
1078                 break;
1079         }
1080
1081         if (ret == 0 && ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
1082                 cancel_delayed_work(&sdata->u.mgd.tdls_peer_del_work);
1083                 eth_zero_addr(sdata->u.mgd.tdls_peer);
1084         }
1085
1086         mutex_unlock(&local->mtx);
1087         return ret;
1088 }
1089
1090 void ieee80211_tdls_oper_request(struct ieee80211_vif *vif, const u8 *peer,
1091                                  enum nl80211_tdls_operation oper,
1092                                  u16 reason_code, gfp_t gfp)
1093 {
1094         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1095
1096         if (vif->type != NL80211_IFTYPE_STATION || !vif->bss_conf.assoc) {
1097                 sdata_err(sdata, "Discarding TDLS oper %d - not STA or disconnected\n",
1098                           oper);
1099                 return;
1100         }
1101
1102         cfg80211_tdls_oper_request(sdata->dev, peer, oper, reason_code, gfp);
1103 }
1104 EXPORT_SYMBOL(ieee80211_tdls_oper_request);
1105
1106 static void
1107 iee80211_tdls_add_ch_switch_timing(u8 *buf, u16 switch_time, u16 switch_timeout)
1108 {
1109         struct ieee80211_ch_switch_timing *ch_sw;
1110
1111         *buf++ = WLAN_EID_CHAN_SWITCH_TIMING;
1112         *buf++ = sizeof(struct ieee80211_ch_switch_timing);
1113
1114         ch_sw = (void *)buf;
1115         ch_sw->switch_time = cpu_to_le16(switch_time);
1116         ch_sw->switch_timeout = cpu_to_le16(switch_timeout);
1117 }
1118
1119 /* find switch timing IE in SKB ready for Tx */
1120 static const u8 *ieee80211_tdls_find_sw_timing_ie(struct sk_buff *skb)
1121 {
1122         struct ieee80211_tdls_data *tf;
1123         const u8 *ie_start;
1124
1125         /*
1126          * Get the offset for the new location of the switch timing IE.
1127          * The SKB network header will now point to the "payload_type"
1128          * element of the TDLS data frame struct.
1129          */
1130         tf = container_of(skb->data + skb_network_offset(skb),
1131                           struct ieee80211_tdls_data, payload_type);
1132         ie_start = tf->u.chan_switch_req.variable;
1133         return cfg80211_find_ie(WLAN_EID_CHAN_SWITCH_TIMING, ie_start,
1134                                 skb->len - (ie_start - skb->data));
1135 }
1136
1137 static struct sk_buff *
1138 ieee80211_tdls_ch_sw_tmpl_get(struct sta_info *sta, u8 oper_class,
1139                               struct cfg80211_chan_def *chandef,
1140                               u32 *ch_sw_tm_ie_offset)
1141 {
1142         struct ieee80211_sub_if_data *sdata = sta->sdata;
1143         u8 extra_ies[2 + sizeof(struct ieee80211_sec_chan_offs_ie) +
1144                      2 + sizeof(struct ieee80211_ch_switch_timing)];
1145         int extra_ies_len = 2 + sizeof(struct ieee80211_ch_switch_timing);
1146         u8 *pos = extra_ies;
1147         struct sk_buff *skb;
1148
1149         /*
1150          * if chandef points to a wide channel add a Secondary-Channel
1151          * Offset information element
1152          */
1153         if (chandef->width == NL80211_CHAN_WIDTH_40) {
1154                 struct ieee80211_sec_chan_offs_ie *sec_chan_ie;
1155                 bool ht40plus;
1156
1157                 *pos++ = WLAN_EID_SECONDARY_CHANNEL_OFFSET;
1158                 *pos++ = sizeof(*sec_chan_ie);
1159                 sec_chan_ie = (void *)pos;
1160
1161                 ht40plus = cfg80211_get_chandef_type(chandef) ==
1162                                                         NL80211_CHAN_HT40PLUS;
1163                 sec_chan_ie->sec_chan_offs = ht40plus ?
1164                                              IEEE80211_HT_PARAM_CHA_SEC_ABOVE :
1165                                              IEEE80211_HT_PARAM_CHA_SEC_BELOW;
1166                 pos += sizeof(*sec_chan_ie);
1167
1168                 extra_ies_len += 2 + sizeof(struct ieee80211_sec_chan_offs_ie);
1169         }
1170
1171         /* just set the values to 0, this is a template */
1172         iee80211_tdls_add_ch_switch_timing(pos, 0, 0);
1173
1174         skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1175                                               WLAN_TDLS_CHANNEL_SWITCH_REQUEST,
1176                                               0, 0, !sta->sta.tdls_initiator,
1177                                               extra_ies, extra_ies_len,
1178                                               oper_class, chandef);
1179         if (!skb)
1180                 return NULL;
1181
1182         skb = ieee80211_build_data_template(sdata, skb, 0);
1183         if (IS_ERR(skb)) {
1184                 tdls_dbg(sdata, "Failed building TDLS channel switch frame\n");
1185                 return NULL;
1186         }
1187
1188         if (ch_sw_tm_ie_offset) {
1189                 const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1190
1191                 if (!tm_ie) {
1192                         tdls_dbg(sdata, "No switch timing IE in TDLS switch\n");
1193                         dev_kfree_skb_any(skb);
1194                         return NULL;
1195                 }
1196
1197                 *ch_sw_tm_ie_offset = tm_ie - skb->data;
1198         }
1199
1200         tdls_dbg(sdata,
1201                  "TDLS channel switch request template for %pM ch %d width %d\n",
1202                  sta->sta.addr, chandef->chan->center_freq, chandef->width);
1203         return skb;
1204 }
1205
1206 int
1207 ieee80211_tdls_channel_switch(struct wiphy *wiphy, struct net_device *dev,
1208                               const u8 *addr, u8 oper_class,
1209                               struct cfg80211_chan_def *chandef)
1210 {
1211         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1212         struct ieee80211_local *local = sdata->local;
1213         struct sta_info *sta;
1214         struct sk_buff *skb = NULL;
1215         u32 ch_sw_tm_ie;
1216         int ret;
1217
1218         mutex_lock(&local->sta_mtx);
1219         sta = sta_info_get(sdata, addr);
1220         if (!sta) {
1221                 tdls_dbg(sdata,
1222                          "Invalid TDLS peer %pM for channel switch request\n",
1223                          addr);
1224                 ret = -ENOENT;
1225                 goto out;
1226         }
1227
1228         if (!test_sta_flag(sta, WLAN_STA_TDLS_CHAN_SWITCH)) {
1229                 tdls_dbg(sdata, "TDLS channel switch unsupported by %pM\n",
1230                          addr);
1231                 ret = -ENOTSUPP;
1232                 goto out;
1233         }
1234
1235         skb = ieee80211_tdls_ch_sw_tmpl_get(sta, oper_class, chandef,
1236                                             &ch_sw_tm_ie);
1237         if (!skb) {
1238                 ret = -ENOENT;
1239                 goto out;
1240         }
1241
1242         ret = drv_tdls_channel_switch(local, sdata, &sta->sta, oper_class,
1243                                       chandef, skb, ch_sw_tm_ie);
1244         if (!ret)
1245                 set_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1246
1247 out:
1248         mutex_unlock(&local->sta_mtx);
1249         dev_kfree_skb_any(skb);
1250         return ret;
1251 }
1252
1253 void
1254 ieee80211_tdls_cancel_channel_switch(struct wiphy *wiphy,
1255                                      struct net_device *dev,
1256                                      const u8 *addr)
1257 {
1258         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1259         struct ieee80211_local *local = sdata->local;
1260         struct sta_info *sta;
1261
1262         mutex_lock(&local->sta_mtx);
1263         sta = sta_info_get(sdata, addr);
1264         if (!sta) {
1265                 tdls_dbg(sdata,
1266                          "Invalid TDLS peer %pM for channel switch cancel\n",
1267                          addr);
1268                 goto out;
1269         }
1270
1271         if (!test_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL)) {
1272                 tdls_dbg(sdata, "TDLS channel switch not initiated by %pM\n",
1273                          addr);
1274                 goto out;
1275         }
1276
1277         drv_tdls_cancel_channel_switch(local, sdata, &sta->sta);
1278         clear_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1279
1280 out:
1281         mutex_unlock(&local->sta_mtx);
1282 }