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                         cfg80211_chandef_create(&chandef, ch,
  72                                                 NL80211_CHAN_NO_HT);
  73                         if (cfg80211_reg_can_beacon(sdata->local->hw.wiphy,
  74                                                     &chandef,
  75                                                     sdata->wdev.iftype)) {
  76                                 ch_cnt++;
  77                                 /*
  78                                  * check if the next channel is also part of
  79                                  * this allowed range
  80                                  */
  81                                 continue;
  82                         }
  83                 }
  84
  85                 /*
  86                  * we've reached the end of a range, with allowed channels
  87                  * found
  88                  */
  89                 if (ch_cnt) {
  90                         u8 *pos = skb_put(skb, 2);
  91                         *pos++ = ieee80211_frequency_to_channel(subband_start);
  92                         *pos++ = ch_cnt;
  93
  94                         subband_cnt++;
  95                         ch_cnt = 0;
  96                 }
  97         }
  98
  99         /* all channels in the requested range are allowed - add them here */
 100         if (ch_cnt) {
 101                 u8 *pos = skb_put(skb, 2);
 102                 *pos++ = ieee80211_frequency_to_channel(subband_start);
 103                 *pos++ = ch_cnt;
 104
 105                 subband_cnt++;
 106         }
 107
 108         return subband_cnt;
 109 }
 110
 111 static void
 112 ieee80211_tdls_add_supp_channels(struct ieee80211_sub_if_data *sdata,
 113                                  struct sk_buff *skb)
 114 {
 115         /*
 116          * Add possible channels for TDLS. These are channels that are allowed
 117          * to be active.
 118          */
 119         u8 subband_cnt;
 120         u8 *pos = skb_put(skb, 2);
 121
 122         *pos++ = WLAN_EID_SUPPORTED_CHANNELS;
 123
 124         /*
 125          * 5GHz and 2GHz channels numbers can overlap. Ignore this for now, as
 126          * this doesn't happen in real world scenarios.
 127          */
 128
 129         /* 2GHz, with 5MHz spacing */
 130         subband_cnt = ieee80211_tdls_add_subband(sdata, skb, 2412, 2472, 5);
 131
 132         /* 5GHz, with 20MHz spacing */
 133         subband_cnt += ieee80211_tdls_add_subband(sdata, skb, 5000, 5825, 20);
 134
 135         /* length */
 136         *pos = 2 * subband_cnt;
 137 }
 138
 139 static void ieee80211_tdls_add_bss_coex_ie(struct sk_buff *skb)
 140 {
 141         u8 *pos = (void *)skb_put(skb, 3);
 142
 143         *pos++ = WLAN_EID_BSS_COEX_2040;
 144         *pos++ = 1; /* len */
 145
 146         *pos++ = WLAN_BSS_COEX_INFORMATION_REQUEST;
 147 }
 148
 149 static u16 ieee80211_get_tdls_sta_capab(struct ieee80211_sub_if_data *sdata,
 150                                         u16 status_code)
 151 {
 152         struct ieee80211_local *local = sdata->local;
 153         u16 capab;
 154
 155         /* The capability will be 0 when sending a failure code */
 156         if (status_code != 0)
 157                 return 0;
 158
 159         capab = 0;
 160         if (ieee80211_get_sdata_band(sdata) != IEEE80211_BAND_2GHZ)
 161                 return capab;
 162
 163         if (!(local->hw.flags & IEEE80211_HW_2GHZ_SHORT_SLOT_INCAPABLE))
 164                 capab |= WLAN_CAPABILITY_SHORT_SLOT_TIME;
 165         if (!(local->hw.flags & IEEE80211_HW_2GHZ_SHORT_PREAMBLE_INCAPABLE))
 166                 capab |= WLAN_CAPABILITY_SHORT_PREAMBLE;
 167
 168         return capab;
 169 }
 170
 171 static void ieee80211_tdls_add_link_ie(struct ieee80211_sub_if_data *sdata,
 172                                        struct sk_buff *skb, const u8 *peer,
 173                                        bool initiator)
 174 {
 175         struct ieee80211_tdls_lnkie *lnkid;
 176         const u8 *init_addr, *rsp_addr;
 177
 178         if (initiator) {
 179                 init_addr = sdata->vif.addr;
 180                 rsp_addr = peer;
 181         } else {
 182                 init_addr = peer;
 183                 rsp_addr = sdata->vif.addr;
 184         }
 185
 186         lnkid = (void *)skb_put(skb, sizeof(struct ieee80211_tdls_lnkie));
 187
 188         lnkid->ie_type = WLAN_EID_LINK_ID;
 189         lnkid->ie_len = sizeof(struct ieee80211_tdls_lnkie) - 2;
 190
 191         memcpy(lnkid->bssid, sdata->u.mgd.bssid, ETH_ALEN);
 192         memcpy(lnkid->init_sta, init_addr, ETH_ALEN);
 193         memcpy(lnkid->resp_sta, rsp_addr, ETH_ALEN);
 194 }
 195
 196 /* translate numbering in the WMM parameter IE to the mac80211 notation */
 197 static enum ieee80211_ac_numbers ieee80211_ac_from_wmm(int ac)
 198 {
 199         switch (ac) {
 200         default:
 201                 WARN_ON_ONCE(1);
 202         case 0:
 203                 return IEEE80211_AC_BE;
 204         case 1:
 205                 return IEEE80211_AC_BK;
 206         case 2:
 207                 return IEEE80211_AC_VI;
 208         case 3:
 209                 return IEEE80211_AC_VO;
 210         }
 211 }
 212
 213 static u8 ieee80211_wmm_aci_aifsn(int aifsn, bool acm, int aci)
 214 {
 215         u8 ret;
 216
 217         ret = aifsn & 0x0f;
 218         if (acm)
 219                 ret |= 0x10;
 220         ret |= (aci << 5) & 0x60;
 221         return ret;
 222 }
 223
 224 static u8 ieee80211_wmm_ecw(u16 cw_min, u16 cw_max)
 225 {
 226         return ((ilog2(cw_min + 1) << 0x0) & 0x0f) |
 227                ((ilog2(cw_max + 1) << 0x4) & 0xf0);
 228 }
 229
 230 static void ieee80211_tdls_add_wmm_param_ie(struct ieee80211_sub_if_data *sdata,
 231                                             struct sk_buff *skb)
 232 {
 233         struct ieee80211_wmm_param_ie *wmm;
 234         struct ieee80211_tx_queue_params *txq;
 235         int i;
 236
 237         wmm = (void *)skb_put(skb, sizeof(*wmm));
 238         memset(wmm, 0, sizeof(*wmm));
 239
 240         wmm->element_id = WLAN_EID_VENDOR_SPECIFIC;
 241         wmm->len = sizeof(*wmm) - 2;
 242
 243         wmm->oui[0] = 0x00; /* Microsoft OUI 00:50:F2 */
 244         wmm->oui[1] = 0x50;
 245         wmm->oui[2] = 0xf2;
 246         wmm->oui_type = 2; /* WME */
 247         wmm->oui_subtype = 1; /* WME param */
 248         wmm->version = 1; /* WME ver */
 249         wmm->qos_info = 0; /* U-APSD not in use */
 250
 251         /*
 252          * Use the EDCA parameters defined for the BSS, or default if the AP
 253          * doesn't support it, as mandated by 802.11-2012 section 10.22.4
 254          */
 255         for (i = 0; i < IEEE80211_NUM_ACS; i++) {
 256                 txq = &sdata->tx_conf[ieee80211_ac_from_wmm(i)];
 257                 wmm->ac[i].aci_aifsn = ieee80211_wmm_aci_aifsn(txq->aifs,
 258                                                                txq->acm, i);
 259                 wmm->ac[i].cw = ieee80211_wmm_ecw(txq->cw_min, txq->cw_max);
 260                 wmm->ac[i].txop_limit = cpu_to_le16(txq->txop);
 261         }
 262 }
 263
 264 static void
 265 ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
 266                                    struct sk_buff *skb, const u8 *peer,
 267                                    u8 action_code, bool initiator,
 268                                    const u8 *extra_ies, size_t extra_ies_len)
 269 {
 270         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
 271         struct ieee80211_local *local = sdata->local;
 272         struct ieee80211_supported_band *sband;
 273         struct ieee80211_sta_ht_cap ht_cap;
 274         struct sta_info *sta = NULL;
 275         size_t offset = 0, noffset;
 276         u8 *pos;
 277
 278         rcu_read_lock();
 279
 280         /* we should have the peer STA if we're already responding */
 281         if (action_code == WLAN_TDLS_SETUP_RESPONSE) {
 282                 sta = sta_info_get(sdata, peer);
 283                 if (WARN_ON_ONCE(!sta)) {
 284                         rcu_read_unlock();
 285                         return;
 286                 }
 287         }
 288
 289         ieee80211_add_srates_ie(sdata, skb, false, band);
 290         ieee80211_add_ext_srates_ie(sdata, skb, false, band);
 291         ieee80211_tdls_add_supp_channels(sdata, skb);
 292
 293         /* add any custom IEs that go before Extended Capabilities */
 294         if (extra_ies_len) {
 295                 static const u8 before_ext_cap[] = {
 296                         WLAN_EID_SUPP_RATES,
 297                         WLAN_EID_COUNTRY,
 298                         WLAN_EID_EXT_SUPP_RATES,
 299                         WLAN_EID_SUPPORTED_CHANNELS,
 300                         WLAN_EID_RSN,
 301                 };
 302                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 303                                              before_ext_cap,
 304                                              ARRAY_SIZE(before_ext_cap),
 305                                              offset);
 306                 pos = skb_put(skb, noffset - offset);
 307                 memcpy(pos, extra_ies + offset, noffset - offset);
 308                 offset = noffset;
 309         }
 310
 311         ieee80211_tdls_add_ext_capab(local, skb);
 312
 313         /* add the QoS element if we support it */
 314         if (local->hw.queues >= IEEE80211_NUM_ACS &&
 315             action_code != WLAN_PUB_ACTION_TDLS_DISCOVER_RES)
 316                 ieee80211_add_wmm_info_ie(skb_put(skb, 9), 0); /* no U-APSD */
 317
 318         /* add any custom IEs that go before HT capabilities */
 319         if (extra_ies_len) {
 320                 static const u8 before_ht_cap[] = {
 321                         WLAN_EID_SUPP_RATES,
 322                         WLAN_EID_COUNTRY,
 323                         WLAN_EID_EXT_SUPP_RATES,
 324                         WLAN_EID_SUPPORTED_CHANNELS,
 325                         WLAN_EID_RSN,
 326                         WLAN_EID_EXT_CAPABILITY,
 327                         WLAN_EID_QOS_CAPA,
 328                         WLAN_EID_FAST_BSS_TRANSITION,
 329                         WLAN_EID_TIMEOUT_INTERVAL,
 330                         WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
 331                 };
 332                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 333                                              before_ht_cap,
 334                                              ARRAY_SIZE(before_ht_cap),
 335                                              offset);
 336                 pos = skb_put(skb, noffset - offset);
 337                 memcpy(pos, extra_ies + offset, noffset - offset);
 338                 offset = noffset;
 339         }
 340
 341         /*
 342          * with TDLS we can switch channels, and HT-caps are not necessarily
 343          * the same on all bands. The specification limits the setup to a
 344          * single HT-cap, so use the current band for now.
 345          */
 346         sband = local->hw.wiphy->bands[band];
 347         memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
 348         if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
 349              action_code == WLAN_TDLS_SETUP_RESPONSE) &&
 350             ht_cap.ht_supported && (!sta || sta->sta.ht_cap.ht_supported)) {
 351                 if (action_code == WLAN_TDLS_SETUP_REQUEST) {
 352                         ieee80211_apply_htcap_overrides(sdata, &ht_cap);
 353
 354                         /* disable SMPS in TDLS initiator */
 355                         ht_cap.cap |= (WLAN_HT_CAP_SM_PS_DISABLED
 356                                        << IEEE80211_HT_CAP_SM_PS_SHIFT);
 357                 } else {
 358                         /* disable SMPS in TDLS responder */
 359                         sta->sta.ht_cap.cap |=
 360                                 (WLAN_HT_CAP_SM_PS_DISABLED
 361                                  << IEEE80211_HT_CAP_SM_PS_SHIFT);
 362
 363                         /* the peer caps are already intersected with our own */
 364                         memcpy(&ht_cap, &sta->sta.ht_cap, sizeof(ht_cap));
 365                 }
 366
 367                 pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
 368                 ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
 369         }
 370
 371         rcu_read_unlock();
 372
 373         if (ht_cap.ht_supported &&
 374             (ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40))
 375                 ieee80211_tdls_add_bss_coex_ie(skb);
 376
 377         /* add any remaining IEs */
 378         if (extra_ies_len) {
 379                 noffset = extra_ies_len;
 380                 pos = skb_put(skb, noffset - offset);
 381                 memcpy(pos, extra_ies + offset, noffset - offset);
 382         }
 383
 384         ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 385 }
 386
 387 static void
 388 ieee80211_tdls_add_setup_cfm_ies(struct ieee80211_sub_if_data *sdata,
 389                                  struct sk_buff *skb, const u8 *peer,
 390                                  bool initiator, const u8 *extra_ies,
 391                                  size_t extra_ies_len)
 392 {
 393         struct ieee80211_local *local = sdata->local;
 394         struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
 395         size_t offset = 0, noffset;
 396         struct sta_info *sta, *ap_sta;
 397         u8 *pos;
 398
 399         rcu_read_lock();
 400
 401         sta = sta_info_get(sdata, peer);
 402         ap_sta = sta_info_get(sdata, ifmgd->bssid);
 403         if (WARN_ON_ONCE(!sta || !ap_sta)) {
 404                 rcu_read_unlock();
 405                 return;
 406         }
 407
 408         /* add any custom IEs that go before the QoS IE */
 409         if (extra_ies_len) {
 410                 static const u8 before_qos[] = {
 411                         WLAN_EID_RSN,
 412                 };
 413                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 414                                              before_qos,
 415                                              ARRAY_SIZE(before_qos),
 416                                              offset);
 417                 pos = skb_put(skb, noffset - offset);
 418                 memcpy(pos, extra_ies + offset, noffset - offset);
 419                 offset = noffset;
 420         }
 421
 422         /* add the QoS param IE if both the peer and we support it */
 423         if (local->hw.queues >= IEEE80211_NUM_ACS && sta->sta.wme)
 424                 ieee80211_tdls_add_wmm_param_ie(sdata, skb);
 425
 426         /* add any custom IEs that go before HT operation */
 427         if (extra_ies_len) {
 428                 static const u8 before_ht_op[] = {
 429                         WLAN_EID_RSN,
 430                         WLAN_EID_QOS_CAPA,
 431                         WLAN_EID_FAST_BSS_TRANSITION,
 432                         WLAN_EID_TIMEOUT_INTERVAL,
 433                 };
 434                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 435                                              before_ht_op,
 436                                              ARRAY_SIZE(before_ht_op),
 437                                              offset);
 438                 pos = skb_put(skb, noffset - offset);
 439                 memcpy(pos, extra_ies + offset, noffset - offset);
 440                 offset = noffset;
 441         }
 442
 443         /* if HT support is only added in TDLS, we need an HT-operation IE */
 444         if (!ap_sta->sta.ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
 445                 struct ieee80211_chanctx_conf *chanctx_conf =
 446                                 rcu_dereference(sdata->vif.chanctx_conf);
 447                 if (!WARN_ON(!chanctx_conf)) {
 448                         pos = skb_put(skb, 2 +
 449                                       sizeof(struct ieee80211_ht_operation));
 450                         /* send an empty HT operation IE */
 451                         ieee80211_ie_build_ht_oper(pos, &sta->sta.ht_cap,
 452                                                    &chanctx_conf->def, 0);
 453                 }
 454         }
 455
 456         rcu_read_unlock();
 457
 458         /* add any remaining IEs */
 459         if (extra_ies_len) {
 460                 noffset = extra_ies_len;
 461                 pos = skb_put(skb, noffset - offset);
 462                 memcpy(pos, extra_ies + offset, noffset - offset);
 463         }
 464
 465         ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 466 }
 467
 468 static void
 469 ieee80211_tdls_add_chan_switch_req_ies(struct ieee80211_sub_if_data *sdata,
 470                                        struct sk_buff *skb, const u8 *peer,
 471                                        bool initiator, const u8 *extra_ies,
 472                                        size_t extra_ies_len, u8 oper_class,
 473                                        struct cfg80211_chan_def *chandef)
 474 {
 475         struct ieee80211_tdls_data *tf;
 476         size_t offset = 0, noffset;
 477         u8 *pos;
 478
 479         if (WARN_ON_ONCE(!chandef))
 480                 return;
 481
 482         tf = (void *)skb->data;
 483         tf->u.chan_switch_req.target_channel =
 484                 ieee80211_frequency_to_channel(chandef->chan->center_freq);
 485         tf->u.chan_switch_req.oper_class = oper_class;
 486
 487         if (extra_ies_len) {
 488                 static const u8 before_lnkie[] = {
 489                         WLAN_EID_SECONDARY_CHANNEL_OFFSET,
 490                 };
 491                 noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
 492                                              before_lnkie,
 493                                              ARRAY_SIZE(before_lnkie),
 494                                              offset);
 495                 pos = skb_put(skb, noffset - offset);
 496                 memcpy(pos, extra_ies + offset, noffset - offset);
 497                 offset = noffset;
 498         }
 499
 500         ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 501
 502         /* add any remaining IEs */
 503         if (extra_ies_len) {
 504                 noffset = extra_ies_len;
 505                 pos = skb_put(skb, noffset - offset);
 506                 memcpy(pos, extra_ies + offset, noffset - offset);
 507         }
 508 }
 509
 510 static void
 511 ieee80211_tdls_add_chan_switch_resp_ies(struct ieee80211_sub_if_data *sdata,
 512                                         struct sk_buff *skb, const u8 *peer,
 513                                         u16 status_code, bool initiator,
 514                                         const u8 *extra_ies,
 515                                         size_t extra_ies_len)
 516 {
 517         if (status_code == 0)
 518                 ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 519
 520         if (extra_ies_len)
 521                 memcpy(skb_put(skb, extra_ies_len), extra_ies, extra_ies_len);
 522 }
 523
 524 static void ieee80211_tdls_add_ies(struct ieee80211_sub_if_data *sdata,
 525                                    struct sk_buff *skb, const u8 *peer,
 526                                    u8 action_code, u16 status_code,
 527                                    bool initiator, const u8 *extra_ies,
 528                                    size_t extra_ies_len, u8 oper_class,
 529                                    struct cfg80211_chan_def *chandef)
 530 {
 531         switch (action_code) {
 532         case WLAN_TDLS_SETUP_REQUEST:
 533         case WLAN_TDLS_SETUP_RESPONSE:
 534         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 535                 if (status_code == 0)
 536                         ieee80211_tdls_add_setup_start_ies(sdata, skb, peer,
 537                                                            action_code,
 538                                                            initiator,
 539                                                            extra_ies,
 540                                                            extra_ies_len);
 541                 break;
 542         case WLAN_TDLS_SETUP_CONFIRM:
 543                 if (status_code == 0)
 544                         ieee80211_tdls_add_setup_cfm_ies(sdata, skb, peer,
 545                                                          initiator, extra_ies,
 546                                                          extra_ies_len);
 547                 break;
 548         case WLAN_TDLS_TEARDOWN:
 549         case WLAN_TDLS_DISCOVERY_REQUEST:
 550                 if (extra_ies_len)
 551                         memcpy(skb_put(skb, extra_ies_len), extra_ies,
 552                                extra_ies_len);
 553                 if (status_code == 0 || action_code == WLAN_TDLS_TEARDOWN)
 554                         ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 555                 break;
 556         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
 557                 ieee80211_tdls_add_chan_switch_req_ies(sdata, skb, peer,
 558                                                        initiator, extra_ies,
 559                                                        extra_ies_len,
 560                                                        oper_class, chandef);
 561                 break;
 562         case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
 563                 ieee80211_tdls_add_chan_switch_resp_ies(sdata, skb, peer,
 564                                                         status_code,
 565                                                         initiator, extra_ies,
 566                                                         extra_ies_len);
 567                 break;
 568         }
 569
 570 }
 571
 572 static int
 573 ieee80211_prep_tdls_encap_data(struct wiphy *wiphy, struct net_device *dev,
 574                                const u8 *peer, u8 action_code, u8 dialog_token,
 575                                u16 status_code, struct sk_buff *skb)
 576 {
 577         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 578         struct ieee80211_tdls_data *tf;
 579
 580         tf = (void *)skb_put(skb, offsetof(struct ieee80211_tdls_data, u));
 581
 582         memcpy(tf->da, peer, ETH_ALEN);
 583         memcpy(tf->sa, sdata->vif.addr, ETH_ALEN);
 584         tf->ether_type = cpu_to_be16(ETH_P_TDLS);
 585         tf->payload_type = WLAN_TDLS_SNAP_RFTYPE;
 586
 587         /* network header is after the ethernet header */
 588         skb_set_network_header(skb, ETH_HLEN);
 589
 590         switch (action_code) {
 591         case WLAN_TDLS_SETUP_REQUEST:
 592                 tf->category = WLAN_CATEGORY_TDLS;
 593                 tf->action_code = WLAN_TDLS_SETUP_REQUEST;
 594
 595                 skb_put(skb, sizeof(tf->u.setup_req));
 596                 tf->u.setup_req.dialog_token = dialog_token;
 597                 tf->u.setup_req.capability =
 598                         cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
 599                                                                  status_code));
 600                 break;
 601         case WLAN_TDLS_SETUP_RESPONSE:
 602                 tf->category = WLAN_CATEGORY_TDLS;
 603                 tf->action_code = WLAN_TDLS_SETUP_RESPONSE;
 604
 605                 skb_put(skb, sizeof(tf->u.setup_resp));
 606                 tf->u.setup_resp.status_code = cpu_to_le16(status_code);
 607                 tf->u.setup_resp.dialog_token = dialog_token;
 608                 tf->u.setup_resp.capability =
 609                         cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
 610                                                                  status_code));
 611                 break;
 612         case WLAN_TDLS_SETUP_CONFIRM:
 613                 tf->category = WLAN_CATEGORY_TDLS;
 614                 tf->action_code = WLAN_TDLS_SETUP_CONFIRM;
 615
 616                 skb_put(skb, sizeof(tf->u.setup_cfm));
 617                 tf->u.setup_cfm.status_code = cpu_to_le16(status_code);
 618                 tf->u.setup_cfm.dialog_token = dialog_token;
 619                 break;
 620         case WLAN_TDLS_TEARDOWN:
 621                 tf->category = WLAN_CATEGORY_TDLS;
 622                 tf->action_code = WLAN_TDLS_TEARDOWN;
 623
 624                 skb_put(skb, sizeof(tf->u.teardown));
 625                 tf->u.teardown.reason_code = cpu_to_le16(status_code);
 626                 break;
 627         case WLAN_TDLS_DISCOVERY_REQUEST:
 628                 tf->category = WLAN_CATEGORY_TDLS;
 629                 tf->action_code = WLAN_TDLS_DISCOVERY_REQUEST;
 630
 631                 skb_put(skb, sizeof(tf->u.discover_req));
 632                 tf->u.discover_req.dialog_token = dialog_token;
 633                 break;
 634         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
 635                 tf->category = WLAN_CATEGORY_TDLS;
 636                 tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
 637
 638                 skb_put(skb, sizeof(tf->u.chan_switch_req));
 639                 break;
 640         case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
 641                 tf->category = WLAN_CATEGORY_TDLS;
 642                 tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
 643
 644                 skb_put(skb, sizeof(tf->u.chan_switch_resp));
 645                 tf->u.chan_switch_resp.status_code = cpu_to_le16(status_code);
 646                 break;
 647         default:
 648                 return -EINVAL;
 649         }
 650
 651         return 0;
 652 }
 653
 654 static int
 655 ieee80211_prep_tdls_direct(struct wiphy *wiphy, struct net_device *dev,
 656                            const u8 *peer, u8 action_code, u8 dialog_token,
 657                            u16 status_code, struct sk_buff *skb)
 658 {
 659         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 660         struct ieee80211_mgmt *mgmt;
 661
 662         mgmt = (void *)skb_put(skb, 24);
 663         memset(mgmt, 0, 24);
 664         memcpy(mgmt->da, peer, ETH_ALEN);
 665         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 666         memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
 667
 668         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 669                                           IEEE80211_STYPE_ACTION);
 670
 671         switch (action_code) {
 672         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 673                 skb_put(skb, 1 + sizeof(mgmt->u.action.u.tdls_discover_resp));
 674                 mgmt->u.action.category = WLAN_CATEGORY_PUBLIC;
 675                 mgmt->u.action.u.tdls_discover_resp.action_code =
 676                         WLAN_PUB_ACTION_TDLS_DISCOVER_RES;
 677                 mgmt->u.action.u.tdls_discover_resp.dialog_token =
 678                         dialog_token;
 679                 mgmt->u.action.u.tdls_discover_resp.capability =
 680                         cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
 681                                                                  status_code));
 682                 break;
 683         default:
 684                 return -EINVAL;
 685         }
 686
 687         return 0;
 688 }
 689
 690 static struct sk_buff *
 691 ieee80211_tdls_build_mgmt_packet_data(struct ieee80211_sub_if_data *sdata,
 692                                       const u8 *peer, u8 action_code,
 693                                       u8 dialog_token, u16 status_code,
 694                                       bool initiator, const u8 *extra_ies,
 695                                       size_t extra_ies_len, u8 oper_class,
 696                                       struct cfg80211_chan_def *chandef)
 697 {
 698         struct ieee80211_local *local = sdata->local;
 699         struct sk_buff *skb;
 700         int ret;
 701
 702         skb = netdev_alloc_skb(sdata->dev,
 703                                local->hw.extra_tx_headroom +
 704                                max(sizeof(struct ieee80211_mgmt),
 705                                    sizeof(struct ieee80211_tdls_data)) +
 706                                50 + /* supported rates */
 707                                7 + /* ext capab */
 708                                26 + /* max(WMM-info, WMM-param) */
 709                                2 + max(sizeof(struct ieee80211_ht_cap),
 710                                        sizeof(struct ieee80211_ht_operation)) +
 711                                50 + /* supported channels */
 712                                3 + /* 40/20 BSS coex */
 713                                extra_ies_len +
 714                                sizeof(struct ieee80211_tdls_lnkie));
 715         if (!skb)
 716                 return NULL;
 717
 718         skb_reserve(skb, local->hw.extra_tx_headroom);
 719
 720         switch (action_code) {
 721         case WLAN_TDLS_SETUP_REQUEST:
 722         case WLAN_TDLS_SETUP_RESPONSE:
 723         case WLAN_TDLS_SETUP_CONFIRM:
 724         case WLAN_TDLS_TEARDOWN:
 725         case WLAN_TDLS_DISCOVERY_REQUEST:
 726         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
 727         case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
 728                 ret = ieee80211_prep_tdls_encap_data(local->hw.wiphy,
 729                                                      sdata->dev, peer,
 730                                                      action_code, dialog_token,
 731                                                      status_code, skb);
 732                 break;
 733         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 734                 ret = ieee80211_prep_tdls_direct(local->hw.wiphy, sdata->dev,
 735                                                  peer, action_code,
 736                                                  dialog_token, status_code,
 737                                                  skb);
 738                 break;
 739         default:
 740                 ret = -ENOTSUPP;
 741                 break;
 742         }
 743
 744         if (ret < 0)
 745                 goto fail;
 746
 747         ieee80211_tdls_add_ies(sdata, skb, peer, action_code, status_code,
 748                                initiator, extra_ies, extra_ies_len, oper_class,
 749                                chandef);
 750         return skb;
 751
 752 fail:
 753         dev_kfree_skb(skb);
 754         return NULL;
 755 }
 756
 757 static int
 758 ieee80211_tdls_prep_mgmt_packet(struct wiphy *wiphy, struct net_device *dev,
 759                                 const u8 *peer, u8 action_code, u8 dialog_token,
 760                                 u16 status_code, u32 peer_capability,
 761                                 bool initiator, const u8 *extra_ies,
 762                                 size_t extra_ies_len, u8 oper_class,
 763                                 struct cfg80211_chan_def *chandef)
 764 {
 765         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 766         struct sk_buff *skb = NULL;
 767         struct sta_info *sta;
 768         u32 flags = 0;
 769         int ret = 0;
 770
 771         rcu_read_lock();
 772         sta = sta_info_get(sdata, peer);
 773
 774         /* infer the initiator if we can, to support old userspace */
 775         switch (action_code) {
 776         case WLAN_TDLS_SETUP_REQUEST:
 777                 if (sta) {
 778                         set_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
 779                         sta->sta.tdls_initiator = false;
 780                 }
 781                 /* fall-through */
 782         case WLAN_TDLS_SETUP_CONFIRM:
 783         case WLAN_TDLS_DISCOVERY_REQUEST:
 784                 initiator = true;
 785                 break;
 786         case WLAN_TDLS_SETUP_RESPONSE:
 787                 /*
 788                  * In some testing scenarios, we send a request and response.
 789                  * Make the last packet sent take effect for the initiator
 790                  * value.
 791                  */
 792                 if (sta) {
 793                         clear_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
 794                         sta->sta.tdls_initiator = true;
 795                 }
 796                 /* fall-through */
 797         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 798                 initiator = false;
 799                 break;
 800         case WLAN_TDLS_TEARDOWN:
 801         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
 802         case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
 803                 /* any value is ok */
 804                 break;
 805         default:
 806                 ret = -ENOTSUPP;
 807                 break;
 808         }
 809
 810         if (sta && test_sta_flag(sta, WLAN_STA_TDLS_INITIATOR))
 811                 initiator = true;
 812
 813         rcu_read_unlock();
 814         if (ret < 0)
 815                 goto fail;
 816
 817         skb = ieee80211_tdls_build_mgmt_packet_data(sdata, peer, action_code,
 818                                                     dialog_token, status_code,
 819                                                     initiator, extra_ies,
 820                                                     extra_ies_len, oper_class,
 821                                                     chandef);
 822         if (!skb) {
 823                 ret = -EINVAL;
 824                 goto fail;
 825         }
 826
 827         if (action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) {
 828                 ieee80211_tx_skb(sdata, skb);
 829                 return 0;
 830         }
 831
 832         /*
 833          * According to 802.11z: Setup req/resp are sent in AC_BK, otherwise
 834          * we should default to AC_VI.
 835          */
 836         switch (action_code) {
 837         case WLAN_TDLS_SETUP_REQUEST:
 838         case WLAN_TDLS_SETUP_RESPONSE:
 839                 skb_set_queue_mapping(skb, IEEE80211_AC_BK);
 840                 skb->priority = 2;
 841                 break;
 842         default:
 843                 skb_set_queue_mapping(skb, IEEE80211_AC_VI);
 844                 skb->priority = 5;
 845                 break;
 846         }
 847
 848         /*
 849          * Set the WLAN_TDLS_TEARDOWN flag to indicate a teardown in progress.
 850          * Later, if no ACK is returned from peer, we will re-send the teardown
 851          * packet through the AP.
 852          */
 853         if ((action_code == WLAN_TDLS_TEARDOWN) &&
 854             (sdata->local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS)) {
 855                 struct sta_info *sta = NULL;
 856                 bool try_resend; /* Should we keep skb for possible resend */
 857
 858                 /* If not sending directly to peer - no point in keeping skb */
 859                 rcu_read_lock();
 860                 sta = sta_info_get(sdata, peer);
 861                 try_resend = sta && test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
 862                 rcu_read_unlock();
 863
 864                 spin_lock_bh(&sdata->u.mgd.teardown_lock);
 865                 if (try_resend && !sdata->u.mgd.teardown_skb) {
 866                         /* Mark it as requiring TX status callback  */
 867                         flags |= IEEE80211_TX_CTL_REQ_TX_STATUS |
 868                                  IEEE80211_TX_INTFL_MLME_CONN_TX;
 869
 870                         /*
 871                          * skb is copied since mac80211 will later set
 872                          * properties that might not be the same as the AP,
 873                          * such as encryption, QoS, addresses, etc.
 874                          *
 875                          * No problem if skb_copy() fails, so no need to check.
 876                          */
 877                         sdata->u.mgd.teardown_skb = skb_copy(skb, GFP_ATOMIC);
 878                         sdata->u.mgd.orig_teardown_skb = skb;
 879                 }
 880                 spin_unlock_bh(&sdata->u.mgd.teardown_lock);
 881         }
 882
 883         /* disable bottom halves when entering the Tx path */
 884         local_bh_disable();
 885         __ieee80211_subif_start_xmit(skb, dev, flags);
 886         local_bh_enable();
 887
 888         return ret;
 889
 890 fail:
 891         dev_kfree_skb(skb);
 892         return ret;
 893 }
 894
 895 static int
 896 ieee80211_tdls_mgmt_setup(struct wiphy *wiphy, struct net_device *dev,
 897                           const u8 *peer, u8 action_code, u8 dialog_token,
 898                           u16 status_code, u32 peer_capability, bool initiator,
 899                           const u8 *extra_ies, size_t extra_ies_len)
 900 {
 901         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 902         struct ieee80211_local *local = sdata->local;
 903         int ret;
 904
 905         mutex_lock(&local->mtx);
 906
 907         /* we don't support concurrent TDLS peer setups */
 908         if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer) &&
 909             !ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
 910                 ret = -EBUSY;
 911                 goto exit;
 912         }
 913
 914         /*
 915          * make sure we have a STA representing the peer so we drop or buffer
 916          * non-TDLS-setup frames to the peer. We can't send other packets
 917          * during setup through the AP path.
 918          * Allow error packets to be sent - sometimes we don't even add a STA
 919          * before failing the setup.
 920          */
 921         if (status_code == 0) {
 922                 rcu_read_lock();
 923                 if (!sta_info_get(sdata, peer)) {
 924                         rcu_read_unlock();
 925                         ret = -ENOLINK;
 926                         goto exit;
 927                 }
 928                 rcu_read_unlock();
 929         }
 930
 931         ieee80211_flush_queues(local, sdata, false);
 932
 933         ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
 934                                               dialog_token, status_code,
 935                                               peer_capability, initiator,
 936                                               extra_ies, extra_ies_len, 0,
 937                                               NULL);
 938         if (ret < 0)
 939                 goto exit;
 940
 941         memcpy(sdata->u.mgd.tdls_peer, peer, ETH_ALEN);
 942         ieee80211_queue_delayed_work(&sdata->local->hw,
 943                                      &sdata->u.mgd.tdls_peer_del_work,
 944                                      TDLS_PEER_SETUP_TIMEOUT);
 945
 946 exit:
 947         mutex_unlock(&local->mtx);
 948         return ret;
 949 }
 950
 951 static int
 952 ieee80211_tdls_mgmt_teardown(struct wiphy *wiphy, struct net_device *dev,
 953                              const u8 *peer, u8 action_code, u8 dialog_token,
 954                              u16 status_code, u32 peer_capability,
 955                              bool initiator, const u8 *extra_ies,
 956                              size_t extra_ies_len)
 957 {
 958         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 959         struct ieee80211_local *local = sdata->local;
 960         struct sta_info *sta;
 961         int ret;
 962
 963         /*
 964          * No packets can be transmitted to the peer via the AP during setup -
 965          * the STA is set as a TDLS peer, but is not authorized.
 966          * During teardown, we prevent direct transmissions by stopping the
 967          * queues and flushing all direct packets.
 968          */
 969         ieee80211_stop_vif_queues(local, sdata,
 970                                   IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
 971         ieee80211_flush_queues(local, sdata, false);
 972
 973         ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
 974                                               dialog_token, status_code,
 975                                               peer_capability, initiator,
 976                                               extra_ies, extra_ies_len, 0,
 977                                               NULL);
 978         if (ret < 0)
 979                 sdata_err(sdata, "Failed sending TDLS teardown packet %d\n",
 980                           ret);
 981
 982         /*
 983          * Remove the STA AUTH flag to force further traffic through the AP. If
 984          * the STA was unreachable, it was already removed.
 985          */
 986         rcu_read_lock();
 987         sta = sta_info_get(sdata, peer);
 988         if (sta)
 989                 clear_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
 990         rcu_read_unlock();
 991
 992         ieee80211_wake_vif_queues(local, sdata,
 993                                   IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
 994
 995         return 0;
 996 }
 997
 998 int ieee80211_tdls_mgmt(struct wiphy *wiphy, struct net_device *dev,
 999                         const u8 *peer, u8 action_code, u8 dialog_token,
1000                         u16 status_code, u32 peer_capability,
1001                         bool initiator, const u8 *extra_ies,
1002                         size_t extra_ies_len)
1003 {
1004         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1005         int ret;
1006
1007         if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
1008                 return -ENOTSUPP;
1009
1010         /* make sure we are in managed mode, and associated */
1011         if (sdata->vif.type != NL80211_IFTYPE_STATION ||
1012             !sdata->u.mgd.associated)
1013                 return -EINVAL;
1014
1015         switch (action_code) {
1016         case WLAN_TDLS_SETUP_REQUEST:
1017         case WLAN_TDLS_SETUP_RESPONSE:
1018                 ret = ieee80211_tdls_mgmt_setup(wiphy, dev, peer, action_code,
1019                                                 dialog_token, status_code,
1020                                                 peer_capability, initiator,
1021                                                 extra_ies, extra_ies_len);
1022                 break;
1023         case WLAN_TDLS_TEARDOWN:
1024                 ret = ieee80211_tdls_mgmt_teardown(wiphy, dev, peer,
1025                                                    action_code, dialog_token,
1026                                                    status_code,
1027                                                    peer_capability, initiator,
1028                                                    extra_ies, extra_ies_len);
1029                 break;
1030         case WLAN_TDLS_DISCOVERY_REQUEST:
1031                 /*
1032                  * Protect the discovery so we can hear the TDLS discovery
1033                  * response frame. It is transmitted directly and not buffered
1034                  * by the AP.
1035                  */
1036                 drv_mgd_protect_tdls_discover(sdata->local, sdata);
1037                 /* fall-through */
1038         case WLAN_TDLS_SETUP_CONFIRM:
1039         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
1040                 /* no special handling */
1041                 ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer,
1042                                                       action_code,
1043                                                       dialog_token,
1044                                                       status_code,
1045                                                       peer_capability,
1046                                                       initiator, extra_ies,
1047                                                       extra_ies_len, 0, NULL);
1048                 break;
1049         default:
1050                 ret = -EOPNOTSUPP;
1051                 break;
1052         }
1053
1054         tdls_dbg(sdata, "TDLS mgmt action %d peer %pM status %d\n",
1055                  action_code, peer, ret);
1056         return ret;
1057 }
1058
1059 int ieee80211_tdls_oper(struct wiphy *wiphy, struct net_device *dev,
1060                         const u8 *peer, enum nl80211_tdls_operation oper)
1061 {
1062         struct sta_info *sta;
1063         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1064         struct ieee80211_local *local = sdata->local;
1065         int ret;
1066
1067         if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
1068                 return -ENOTSUPP;
1069
1070         if (sdata->vif.type != NL80211_IFTYPE_STATION)
1071                 return -EINVAL;
1072
1073         switch (oper) {
1074         case NL80211_TDLS_ENABLE_LINK:
1075         case NL80211_TDLS_DISABLE_LINK:
1076                 break;
1077         case NL80211_TDLS_TEARDOWN:
1078         case NL80211_TDLS_SETUP:
1079         case NL80211_TDLS_DISCOVERY_REQ:
1080                 /* We don't support in-driver setup/teardown/discovery */
1081                 return -ENOTSUPP;
1082         }
1083
1084         mutex_lock(&local->mtx);
1085         tdls_dbg(sdata, "TDLS oper %d peer %pM\n", oper, peer);
1086
1087         switch (oper) {
1088         case NL80211_TDLS_ENABLE_LINK:
1089                 rcu_read_lock();
1090                 sta = sta_info_get(sdata, peer);
1091                 if (!sta) {
1092                         rcu_read_unlock();
1093                         ret = -ENOLINK;
1094                         break;
1095                 }
1096
1097                 set_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1098                 rcu_read_unlock();
1099
1100                 WARN_ON_ONCE(is_zero_ether_addr(sdata->u.mgd.tdls_peer) ||
1101                              !ether_addr_equal(sdata->u.mgd.tdls_peer, peer));
1102                 ret = 0;
1103                 break;
1104         case NL80211_TDLS_DISABLE_LINK:
1105                 /*
1106                  * The teardown message in ieee80211_tdls_mgmt_teardown() was
1107                  * created while the queues were stopped, so it might still be
1108                  * pending. Before flushing the queues we need to be sure the
1109                  * message is handled by the tasklet handling pending messages,
1110                  * otherwise we might start destroying the station before
1111                  * sending the teardown packet.
1112                  * Note that this only forces the tasklet to flush pendings -
1113                  * not to stop the tasklet from rescheduling itself.
1114                  */
1115                 tasklet_kill(&local->tx_pending_tasklet);
1116                 /* flush a potentially queued teardown packet */
1117                 ieee80211_flush_queues(local, sdata, false);
1118
1119                 ret = sta_info_destroy_addr(sdata, peer);
1120                 break;
1121         default:
1122                 ret = -ENOTSUPP;
1123                 break;
1124         }
1125
1126         if (ret == 0 && ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
1127                 cancel_delayed_work(&sdata->u.mgd.tdls_peer_del_work);
1128                 eth_zero_addr(sdata->u.mgd.tdls_peer);
1129         }
1130
1131         mutex_unlock(&local->mtx);
1132         return ret;
1133 }
1134
1135 void ieee80211_tdls_oper_request(struct ieee80211_vif *vif, const u8 *peer,
1136                                  enum nl80211_tdls_operation oper,
1137                                  u16 reason_code, gfp_t gfp)
1138 {
1139         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1140
1141         if (vif->type != NL80211_IFTYPE_STATION || !vif->bss_conf.assoc) {
1142                 sdata_err(sdata, "Discarding TDLS oper %d - not STA or disconnected\n",
1143                           oper);
1144                 return;
1145         }
1146
1147         cfg80211_tdls_oper_request(sdata->dev, peer, oper, reason_code, gfp);
1148 }
1149 EXPORT_SYMBOL(ieee80211_tdls_oper_request);
1150
1151 static void
1152 iee80211_tdls_add_ch_switch_timing(u8 *buf, u16 switch_time, u16 switch_timeout)
1153 {
1154         struct ieee80211_ch_switch_timing *ch_sw;
1155
1156         *buf++ = WLAN_EID_CHAN_SWITCH_TIMING;
1157         *buf++ = sizeof(struct ieee80211_ch_switch_timing);
1158
1159         ch_sw = (void *)buf;
1160         ch_sw->switch_time = cpu_to_le16(switch_time);
1161         ch_sw->switch_timeout = cpu_to_le16(switch_timeout);
1162 }
1163
1164 /* find switch timing IE in SKB ready for Tx */
1165 static const u8 *ieee80211_tdls_find_sw_timing_ie(struct sk_buff *skb)
1166 {
1167         struct ieee80211_tdls_data *tf;
1168         const u8 *ie_start;
1169
1170         /*
1171          * Get the offset for the new location of the switch timing IE.
1172          * The SKB network header will now point to the "payload_type"
1173          * element of the TDLS data frame struct.
1174          */
1175         tf = container_of(skb->data + skb_network_offset(skb),
1176                           struct ieee80211_tdls_data, payload_type);
1177         ie_start = tf->u.chan_switch_req.variable;
1178         return cfg80211_find_ie(WLAN_EID_CHAN_SWITCH_TIMING, ie_start,
1179                                 skb->len - (ie_start - skb->data));
1180 }
1181
1182 static struct sk_buff *
1183 ieee80211_tdls_ch_sw_tmpl_get(struct sta_info *sta, u8 oper_class,
1184                               struct cfg80211_chan_def *chandef,
1185                               u32 *ch_sw_tm_ie_offset)
1186 {
1187         struct ieee80211_sub_if_data *sdata = sta->sdata;
1188         u8 extra_ies[2 + sizeof(struct ieee80211_sec_chan_offs_ie) +
1189                      2 + sizeof(struct ieee80211_ch_switch_timing)];
1190         int extra_ies_len = 2 + sizeof(struct ieee80211_ch_switch_timing);
1191         u8 *pos = extra_ies;
1192         struct sk_buff *skb;
1193
1194         /*
1195          * if chandef points to a wide channel add a Secondary-Channel
1196          * Offset information element
1197          */
1198         if (chandef->width == NL80211_CHAN_WIDTH_40) {
1199                 struct ieee80211_sec_chan_offs_ie *sec_chan_ie;
1200                 bool ht40plus;
1201
1202                 *pos++ = WLAN_EID_SECONDARY_CHANNEL_OFFSET;
1203                 *pos++ = sizeof(*sec_chan_ie);
1204                 sec_chan_ie = (void *)pos;
1205
1206                 ht40plus = cfg80211_get_chandef_type(chandef) ==
1207                                                         NL80211_CHAN_HT40PLUS;
1208                 sec_chan_ie->sec_chan_offs = ht40plus ?
1209                                              IEEE80211_HT_PARAM_CHA_SEC_ABOVE :
1210                                              IEEE80211_HT_PARAM_CHA_SEC_BELOW;
1211                 pos += sizeof(*sec_chan_ie);
1212
1213                 extra_ies_len += 2 + sizeof(struct ieee80211_sec_chan_offs_ie);
1214         }
1215
1216         /* just set the values to 0, this is a template */
1217         iee80211_tdls_add_ch_switch_timing(pos, 0, 0);
1218
1219         skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1220                                               WLAN_TDLS_CHANNEL_SWITCH_REQUEST,
1221                                               0, 0, !sta->sta.tdls_initiator,
1222                                               extra_ies, extra_ies_len,
1223                                               oper_class, chandef);
1224         if (!skb)
1225                 return NULL;
1226
1227         skb = ieee80211_build_data_template(sdata, skb, 0);
1228         if (IS_ERR(skb)) {
1229                 tdls_dbg(sdata, "Failed building TDLS channel switch frame\n");
1230                 return NULL;
1231         }
1232
1233         if (ch_sw_tm_ie_offset) {
1234                 const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1235
1236                 if (!tm_ie) {
1237                         tdls_dbg(sdata, "No switch timing IE in TDLS switch\n");
1238                         dev_kfree_skb_any(skb);
1239                         return NULL;
1240                 }
1241
1242                 *ch_sw_tm_ie_offset = tm_ie - skb->data;
1243         }
1244
1245         tdls_dbg(sdata,
1246                  "TDLS channel switch request template for %pM ch %d width %d\n",
1247                  sta->sta.addr, chandef->chan->center_freq, chandef->width);
1248         return skb;
1249 }
1250
1251 int
1252 ieee80211_tdls_channel_switch(struct wiphy *wiphy, struct net_device *dev,
1253                               const u8 *addr, u8 oper_class,
1254                               struct cfg80211_chan_def *chandef)
1255 {
1256         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1257         struct ieee80211_local *local = sdata->local;
1258         struct sta_info *sta;
1259         struct sk_buff *skb = NULL;
1260         u32 ch_sw_tm_ie;
1261         int ret;
1262
1263         mutex_lock(&local->sta_mtx);
1264         sta = sta_info_get(sdata, addr);
1265         if (!sta) {
1266                 tdls_dbg(sdata,
1267                          "Invalid TDLS peer %pM for channel switch request\n",
1268                          addr);
1269                 ret = -ENOENT;
1270                 goto out;
1271         }
1272
1273         if (!test_sta_flag(sta, WLAN_STA_TDLS_CHAN_SWITCH)) {
1274                 tdls_dbg(sdata, "TDLS channel switch unsupported by %pM\n",
1275                          addr);
1276                 ret = -ENOTSUPP;
1277                 goto out;
1278         }
1279
1280         skb = ieee80211_tdls_ch_sw_tmpl_get(sta, oper_class, chandef,
1281                                             &ch_sw_tm_ie);
1282         if (!skb) {
1283                 ret = -ENOENT;
1284                 goto out;
1285         }
1286
1287         ret = drv_tdls_channel_switch(local, sdata, &sta->sta, oper_class,
1288                                       chandef, skb, ch_sw_tm_ie);
1289         if (!ret)
1290                 set_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1291
1292 out:
1293         mutex_unlock(&local->sta_mtx);
1294         dev_kfree_skb_any(skb);
1295         return ret;
1296 }
1297
1298 void
1299 ieee80211_tdls_cancel_channel_switch(struct wiphy *wiphy,
1300                                      struct net_device *dev,
1301                                      const u8 *addr)
1302 {
1303         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1304         struct ieee80211_local *local = sdata->local;
1305         struct sta_info *sta;
1306
1307         mutex_lock(&local->sta_mtx);
1308         sta = sta_info_get(sdata, addr);
1309         if (!sta) {
1310                 tdls_dbg(sdata,
1311                          "Invalid TDLS peer %pM for channel switch cancel\n",
1312                          addr);
1313                 goto out;
1314         }
1315
1316         if (!test_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL)) {
1317                 tdls_dbg(sdata, "TDLS channel switch not initiated by %pM\n",
1318                          addr);
1319                 goto out;
1320         }
1321
1322         drv_tdls_cancel_channel_switch(local, sdata, &sta->sta);
1323         clear_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1324
1325 out:
1326         mutex_unlock(&local->sta_mtx);
1327 }
1328
1329 static struct sk_buff *
1330 ieee80211_tdls_ch_sw_resp_tmpl_get(struct sta_info *sta,
1331                                    u32 *ch_sw_tm_ie_offset)
1332 {
1333         struct ieee80211_sub_if_data *sdata = sta->sdata;
1334         struct sk_buff *skb;
1335         u8 extra_ies[2 + sizeof(struct ieee80211_ch_switch_timing)];
1336
1337         /* initial timing are always zero in the template */
1338         iee80211_tdls_add_ch_switch_timing(extra_ies, 0, 0);
1339
1340         skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1341                                         WLAN_TDLS_CHANNEL_SWITCH_RESPONSE,
1342                                         0, 0, !sta->sta.tdls_initiator,
1343                                         extra_ies, sizeof(extra_ies), 0, NULL);
1344         if (!skb)
1345                 return NULL;
1346
1347         skb = ieee80211_build_data_template(sdata, skb, 0);
1348         if (IS_ERR(skb)) {
1349                 tdls_dbg(sdata,
1350                          "Failed building TDLS channel switch resp frame\n");
1351                 return NULL;
1352         }
1353
1354         if (ch_sw_tm_ie_offset) {
1355                 const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1356
1357                 if (!tm_ie) {
1358                         tdls_dbg(sdata,
1359                                  "No switch timing IE in TDLS switch resp\n");
1360                         dev_kfree_skb_any(skb);
1361                         return NULL;
1362                 }
1363
1364                 *ch_sw_tm_ie_offset = tm_ie - skb->data;
1365         }
1366
1367         tdls_dbg(sdata, "TDLS get channel switch response template for %pM\n",
1368                  sta->sta.addr);
1369         return skb;
1370 }
1371
1372 static int
1373 ieee80211_process_tdls_channel_switch_resp(struct ieee80211_sub_if_data *sdata,
1374                                            struct sk_buff *skb)
1375 {
1376         struct ieee80211_local *local = sdata->local;
1377         struct ieee802_11_elems elems;
1378         struct sta_info *sta;
1379         struct ieee80211_tdls_data *tf = (void *)skb->data;
1380         bool local_initiator;
1381         struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1382         int baselen = offsetof(typeof(*tf), u.chan_switch_resp.variable);
1383         struct ieee80211_tdls_ch_sw_params params = {};
1384         int ret;
1385
1386         params.action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
1387         params.timestamp = rx_status->device_timestamp;
1388
1389         if (skb->len < baselen) {
1390                 tdls_dbg(sdata, "TDLS channel switch resp too short: %d\n",
1391                          skb->len);
1392                 return -EINVAL;
1393         }
1394
1395         mutex_lock(&local->sta_mtx);
1396         sta = sta_info_get(sdata, tf->sa);
1397         if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1398                 tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1399                          tf->sa);
1400                 ret = -EINVAL;
1401                 goto out;
1402         }
1403
1404         params.sta = &sta->sta;
1405         params.status = le16_to_cpu(tf->u.chan_switch_resp.status_code);
1406         if (params.status != 0) {
1407                 ret = 0;
1408                 goto call_drv;
1409         }
1410
1411         ieee802_11_parse_elems(tf->u.chan_switch_resp.variable,
1412                                skb->len - baselen, false, &elems);
1413         if (elems.parse_error) {
1414                 tdls_dbg(sdata, "Invalid IEs in TDLS channel switch resp\n");
1415                 ret = -EINVAL;
1416                 goto out;
1417         }
1418
1419         if (!elems.ch_sw_timing || !elems.lnk_id) {
1420                 tdls_dbg(sdata, "TDLS channel switch resp - missing IEs\n");
1421                 ret = -EINVAL;
1422                 goto out;
1423         }
1424
1425         /* validate the initiator is set correctly */
1426         local_initiator =
1427                 !memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1428         if (local_initiator == sta->sta.tdls_initiator) {
1429                 tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1430                 ret = -EINVAL;
1431                 goto out;
1432         }
1433
1434         params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1435         params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1436
1437         params.tmpl_skb =
1438                 ieee80211_tdls_ch_sw_resp_tmpl_get(sta, &params.ch_sw_tm_ie);
1439         if (!params.tmpl_skb) {
1440                 ret = -ENOENT;
1441                 goto out;
1442         }
1443
1444 call_drv:
1445         drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1446
1447         tdls_dbg(sdata,
1448                  "TDLS channel switch response received from %pM status %d\n",
1449                  tf->sa, params.status);
1450
1451 out:
1452         mutex_unlock(&local->sta_mtx);
1453         dev_kfree_skb_any(params.tmpl_skb);
1454         return ret;
1455 }
1456
1457 static int
1458 ieee80211_process_tdls_channel_switch_req(struct ieee80211_sub_if_data *sdata,
1459                                           struct sk_buff *skb)
1460 {
1461         struct ieee80211_local *local = sdata->local;
1462         struct ieee802_11_elems elems;
1463         struct cfg80211_chan_def chandef;
1464         struct ieee80211_channel *chan;
1465         enum nl80211_channel_type chan_type;
1466         int freq;
1467         u8 target_channel, oper_class;
1468         bool local_initiator;
1469         struct sta_info *sta;
1470         enum ieee80211_band band;
1471         struct ieee80211_tdls_data *tf = (void *)skb->data;
1472         struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1473         int baselen = offsetof(typeof(*tf), u.chan_switch_req.variable);
1474         struct ieee80211_tdls_ch_sw_params params = {};
1475         int ret = 0;
1476
1477         params.action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
1478         params.timestamp = rx_status->device_timestamp;
1479
1480         if (skb->len < baselen) {
1481                 tdls_dbg(sdata, "TDLS channel switch req too short: %d\n",
1482                          skb->len);
1483                 return -EINVAL;
1484         }
1485
1486         target_channel = tf->u.chan_switch_req.target_channel;
1487         oper_class = tf->u.chan_switch_req.oper_class;
1488
1489         /*
1490          * We can't easily infer the channel band. The operating class is
1491          * ambiguous - there are multiple tables (US/Europe/JP/Global). The
1492          * solution here is to treat channels with number >14 as 5GHz ones,
1493          * and specifically check for the (oper_class, channel) combinations
1494          * where this doesn't hold. These are thankfully unique according to
1495          * IEEE802.11-2012.
1496          * We consider only the 2GHz and 5GHz bands and 20MHz+ channels as
1497          * valid here.
1498          */
1499         if ((oper_class == 112 || oper_class == 2 || oper_class == 3 ||
1500              oper_class == 4 || oper_class == 5 || oper_class == 6) &&
1501              target_channel < 14)
1502                 band = IEEE80211_BAND_5GHZ;
1503         else
1504                 band = target_channel < 14 ? IEEE80211_BAND_2GHZ :
1505                                              IEEE80211_BAND_5GHZ;
1506
1507         freq = ieee80211_channel_to_frequency(target_channel, band);
1508         if (freq == 0) {
1509                 tdls_dbg(sdata, "Invalid channel in TDLS chan switch: %d\n",
1510                          target_channel);
1511                 return -EINVAL;
1512         }
1513
1514         chan = ieee80211_get_channel(sdata->local->hw.wiphy, freq);
1515         if (!chan) {
1516                 tdls_dbg(sdata,
1517                          "Unsupported channel for TDLS chan switch: %d\n",
1518                          target_channel);
1519                 return -EINVAL;
1520         }
1521
1522         ieee802_11_parse_elems(tf->u.chan_switch_req.variable,
1523                                skb->len - baselen, false, &elems);
1524         if (elems.parse_error) {
1525                 tdls_dbg(sdata, "Invalid IEs in TDLS channel switch req\n");
1526                 return -EINVAL;
1527         }
1528
1529         if (!elems.ch_sw_timing || !elems.lnk_id) {
1530                 tdls_dbg(sdata, "TDLS channel switch req - missing IEs\n");
1531                 return -EINVAL;
1532         }
1533
1534         mutex_lock(&local->sta_mtx);
1535         sta = sta_info_get(sdata, tf->sa);
1536         if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1537                 tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1538                          tf->sa);
1539                 ret = -EINVAL;
1540                 goto out;
1541         }
1542
1543         params.sta = &sta->sta;
1544
1545         /* validate the initiator is set correctly */
1546         local_initiator =
1547                 !memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1548         if (local_initiator == sta->sta.tdls_initiator) {
1549                 tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1550                 ret = -EINVAL;
1551                 goto out;
1552         }
1553
1554         if (!sta->sta.ht_cap.ht_supported) {
1555                 chan_type = NL80211_CHAN_NO_HT;
1556         } else if (!elems.sec_chan_offs) {
1557                 chan_type = NL80211_CHAN_HT20;
1558         } else {
1559                 switch (elems.sec_chan_offs->sec_chan_offs) {
1560                 case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
1561                         chan_type = NL80211_CHAN_HT40PLUS;
1562                         break;
1563                 case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
1564                         chan_type = NL80211_CHAN_HT40MINUS;
1565                         break;
1566                 default:
1567                         chan_type = NL80211_CHAN_HT20;
1568                         break;
1569                 }
1570         }
1571
1572         cfg80211_chandef_create(&chandef, chan, chan_type);
1573         params.chandef = &chandef;
1574
1575         params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1576         params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1577
1578         params.tmpl_skb =
1579                 ieee80211_tdls_ch_sw_resp_tmpl_get(sta,
1580                                                    &params.ch_sw_tm_ie);
1581         if (!params.tmpl_skb) {
1582                 ret = -ENOENT;
1583                 goto out;
1584         }
1585
1586         drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1587
1588         tdls_dbg(sdata,
1589                  "TDLS ch switch request received from %pM ch %d width %d\n",
1590                  tf->sa, params.chandef->chan->center_freq,
1591                  params.chandef->width);
1592 out:
1593         mutex_unlock(&local->sta_mtx);
1594         dev_kfree_skb_any(params.tmpl_skb);
1595         return ret;
1596 }
1597
1598 void ieee80211_process_tdls_channel_switch(struct ieee80211_sub_if_data *sdata,
1599                                            struct sk_buff *skb)
1600 {
1601         struct ieee80211_tdls_data *tf = (void *)skb->data;
1602         struct wiphy *wiphy = sdata->local->hw.wiphy;
1603
1604         /* make sure the driver supports it */
1605         if (!(wiphy->features & NL80211_FEATURE_TDLS_CHANNEL_SWITCH))
1606                 return;
1607
1608         /* we want to access the entire packet */
1609         if (skb_linearize(skb))
1610                 return;
1611         /*
1612          * The packet/size was already validated by mac80211 Rx path, only look
1613          * at the action type.
1614          */
1615         switch (tf->action_code) {
1616         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
1617                 ieee80211_process_tdls_channel_switch_req(sdata, skb);
1618                 break;
1619         case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
1620                 ieee80211_process_tdls_channel_switch_resp(sdata, skb);
1621                 break;
1622         default:
1623                 WARN_ON_ONCE(1);
1624                 return;
1625         }
1626 }