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
 495 ieee80211_tdls_add_chan_switch_resp_ies(struct ieee80211_sub_if_data *sdata,
 496                                         struct sk_buff *skb, const u8 *peer,
 497                                         u16 status_code, bool initiator,
 498                                         const u8 *extra_ies,
 499                                         size_t extra_ies_len)
 500 {
 501         if (status_code == 0)
 502                 ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 503
 504         if (extra_ies_len)
 505                 memcpy(skb_put(skb, extra_ies_len), extra_ies, extra_ies_len);
 506 }
 507
 508 static void ieee80211_tdls_add_ies(struct ieee80211_sub_if_data *sdata,
 509                                    struct sk_buff *skb, const u8 *peer,
 510                                    u8 action_code, u16 status_code,
 511                                    bool initiator, const u8 *extra_ies,
 512                                    size_t extra_ies_len, u8 oper_class,
 513                                    struct cfg80211_chan_def *chandef)
 514 {
 515         switch (action_code) {
 516         case WLAN_TDLS_SETUP_REQUEST:
 517         case WLAN_TDLS_SETUP_RESPONSE:
 518         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 519                 if (status_code == 0)
 520                         ieee80211_tdls_add_setup_start_ies(sdata, skb, peer,
 521                                                            action_code,
 522                                                            initiator,
 523                                                            extra_ies,
 524                                                            extra_ies_len);
 525                 break;
 526         case WLAN_TDLS_SETUP_CONFIRM:
 527                 if (status_code == 0)
 528                         ieee80211_tdls_add_setup_cfm_ies(sdata, skb, peer,
 529                                                          initiator, extra_ies,
 530                                                          extra_ies_len);
 531                 break;
 532         case WLAN_TDLS_TEARDOWN:
 533         case WLAN_TDLS_DISCOVERY_REQUEST:
 534                 if (extra_ies_len)
 535                         memcpy(skb_put(skb, extra_ies_len), extra_ies,
 536                                extra_ies_len);
 537                 if (status_code == 0 || action_code == WLAN_TDLS_TEARDOWN)
 538                         ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
 539                 break;
 540         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
 541                 ieee80211_tdls_add_chan_switch_req_ies(sdata, skb, peer,
 542                                                        initiator, extra_ies,
 543                                                        extra_ies_len,
 544                                                        oper_class, chandef);
 545                 break;
 546         case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
 547                 ieee80211_tdls_add_chan_switch_resp_ies(sdata, skb, peer,
 548                                                         status_code,
 549                                                         initiator, extra_ies,
 550                                                         extra_ies_len);
 551                 break;
 552         }
 553
 554 }
 555
 556 static int
 557 ieee80211_prep_tdls_encap_data(struct wiphy *wiphy, struct net_device *dev,
 558                                const u8 *peer, u8 action_code, u8 dialog_token,
 559                                u16 status_code, struct sk_buff *skb)
 560 {
 561         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 562         struct ieee80211_tdls_data *tf;
 563
 564         tf = (void *)skb_put(skb, offsetof(struct ieee80211_tdls_data, u));
 565
 566         memcpy(tf->da, peer, ETH_ALEN);
 567         memcpy(tf->sa, sdata->vif.addr, ETH_ALEN);
 568         tf->ether_type = cpu_to_be16(ETH_P_TDLS);
 569         tf->payload_type = WLAN_TDLS_SNAP_RFTYPE;
 570
 571         /* network header is after the ethernet header */
 572         skb_set_network_header(skb, ETH_HLEN);
 573
 574         switch (action_code) {
 575         case WLAN_TDLS_SETUP_REQUEST:
 576                 tf->category = WLAN_CATEGORY_TDLS;
 577                 tf->action_code = WLAN_TDLS_SETUP_REQUEST;
 578
 579                 skb_put(skb, sizeof(tf->u.setup_req));
 580                 tf->u.setup_req.dialog_token = dialog_token;
 581                 tf->u.setup_req.capability =
 582                         cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
 583                                                                  status_code));
 584                 break;
 585         case WLAN_TDLS_SETUP_RESPONSE:
 586                 tf->category = WLAN_CATEGORY_TDLS;
 587                 tf->action_code = WLAN_TDLS_SETUP_RESPONSE;
 588
 589                 skb_put(skb, sizeof(tf->u.setup_resp));
 590                 tf->u.setup_resp.status_code = cpu_to_le16(status_code);
 591                 tf->u.setup_resp.dialog_token = dialog_token;
 592                 tf->u.setup_resp.capability =
 593                         cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
 594                                                                  status_code));
 595                 break;
 596         case WLAN_TDLS_SETUP_CONFIRM:
 597                 tf->category = WLAN_CATEGORY_TDLS;
 598                 tf->action_code = WLAN_TDLS_SETUP_CONFIRM;
 599
 600                 skb_put(skb, sizeof(tf->u.setup_cfm));
 601                 tf->u.setup_cfm.status_code = cpu_to_le16(status_code);
 602                 tf->u.setup_cfm.dialog_token = dialog_token;
 603                 break;
 604         case WLAN_TDLS_TEARDOWN:
 605                 tf->category = WLAN_CATEGORY_TDLS;
 606                 tf->action_code = WLAN_TDLS_TEARDOWN;
 607
 608                 skb_put(skb, sizeof(tf->u.teardown));
 609                 tf->u.teardown.reason_code = cpu_to_le16(status_code);
 610                 break;
 611         case WLAN_TDLS_DISCOVERY_REQUEST:
 612                 tf->category = WLAN_CATEGORY_TDLS;
 613                 tf->action_code = WLAN_TDLS_DISCOVERY_REQUEST;
 614
 615                 skb_put(skb, sizeof(tf->u.discover_req));
 616                 tf->u.discover_req.dialog_token = dialog_token;
 617                 break;
 618         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
 619                 tf->category = WLAN_CATEGORY_TDLS;
 620                 tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
 621
 622                 skb_put(skb, sizeof(tf->u.chan_switch_req));
 623                 break;
 624         case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
 625                 tf->category = WLAN_CATEGORY_TDLS;
 626                 tf->action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
 627
 628                 skb_put(skb, sizeof(tf->u.chan_switch_resp));
 629                 tf->u.chan_switch_resp.status_code = cpu_to_le16(status_code);
 630                 break;
 631         default:
 632                 return -EINVAL;
 633         }
 634
 635         return 0;
 636 }
 637
 638 static int
 639 ieee80211_prep_tdls_direct(struct wiphy *wiphy, struct net_device *dev,
 640                            const u8 *peer, u8 action_code, u8 dialog_token,
 641                            u16 status_code, struct sk_buff *skb)
 642 {
 643         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 644         struct ieee80211_mgmt *mgmt;
 645
 646         mgmt = (void *)skb_put(skb, 24);
 647         memset(mgmt, 0, 24);
 648         memcpy(mgmt->da, peer, ETH_ALEN);
 649         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 650         memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
 651
 652         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 653                                           IEEE80211_STYPE_ACTION);
 654
 655         switch (action_code) {
 656         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 657                 skb_put(skb, 1 + sizeof(mgmt->u.action.u.tdls_discover_resp));
 658                 mgmt->u.action.category = WLAN_CATEGORY_PUBLIC;
 659                 mgmt->u.action.u.tdls_discover_resp.action_code =
 660                         WLAN_PUB_ACTION_TDLS_DISCOVER_RES;
 661                 mgmt->u.action.u.tdls_discover_resp.dialog_token =
 662                         dialog_token;
 663                 mgmt->u.action.u.tdls_discover_resp.capability =
 664                         cpu_to_le16(ieee80211_get_tdls_sta_capab(sdata,
 665                                                                  status_code));
 666                 break;
 667         default:
 668                 return -EINVAL;
 669         }
 670
 671         return 0;
 672 }
 673
 674 static struct sk_buff *
 675 ieee80211_tdls_build_mgmt_packet_data(struct ieee80211_sub_if_data *sdata,
 676                                       const u8 *peer, u8 action_code,
 677                                       u8 dialog_token, u16 status_code,
 678                                       bool initiator, const u8 *extra_ies,
 679                                       size_t extra_ies_len, u8 oper_class,
 680                                       struct cfg80211_chan_def *chandef)
 681 {
 682         struct ieee80211_local *local = sdata->local;
 683         struct sk_buff *skb;
 684         int ret;
 685
 686         skb = netdev_alloc_skb(sdata->dev,
 687                                local->hw.extra_tx_headroom +
 688                                max(sizeof(struct ieee80211_mgmt),
 689                                    sizeof(struct ieee80211_tdls_data)) +
 690                                50 + /* supported rates */
 691                                7 + /* ext capab */
 692                                26 + /* max(WMM-info, WMM-param) */
 693                                2 + max(sizeof(struct ieee80211_ht_cap),
 694                                        sizeof(struct ieee80211_ht_operation)) +
 695                                50 + /* supported channels */
 696                                3 + /* 40/20 BSS coex */
 697                                extra_ies_len +
 698                                sizeof(struct ieee80211_tdls_lnkie));
 699         if (!skb)
 700                 return NULL;
 701
 702         skb_reserve(skb, local->hw.extra_tx_headroom);
 703
 704         switch (action_code) {
 705         case WLAN_TDLS_SETUP_REQUEST:
 706         case WLAN_TDLS_SETUP_RESPONSE:
 707         case WLAN_TDLS_SETUP_CONFIRM:
 708         case WLAN_TDLS_TEARDOWN:
 709         case WLAN_TDLS_DISCOVERY_REQUEST:
 710         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
 711         case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
 712                 ret = ieee80211_prep_tdls_encap_data(local->hw.wiphy,
 713                                                      sdata->dev, peer,
 714                                                      action_code, dialog_token,
 715                                                      status_code, skb);
 716                 break;
 717         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 718                 ret = ieee80211_prep_tdls_direct(local->hw.wiphy, sdata->dev,
 719                                                  peer, action_code,
 720                                                  dialog_token, status_code,
 721                                                  skb);
 722                 break;
 723         default:
 724                 ret = -ENOTSUPP;
 725                 break;
 726         }
 727
 728         if (ret < 0)
 729                 goto fail;
 730
 731         ieee80211_tdls_add_ies(sdata, skb, peer, action_code, status_code,
 732                                initiator, extra_ies, extra_ies_len, oper_class,
 733                                chandef);
 734         return skb;
 735
 736 fail:
 737         dev_kfree_skb(skb);
 738         return NULL;
 739 }
 740
 741 static int
 742 ieee80211_tdls_prep_mgmt_packet(struct wiphy *wiphy, struct net_device *dev,
 743                                 const u8 *peer, u8 action_code, u8 dialog_token,
 744                                 u16 status_code, u32 peer_capability,
 745                                 bool initiator, const u8 *extra_ies,
 746                                 size_t extra_ies_len, u8 oper_class,
 747                                 struct cfg80211_chan_def *chandef)
 748 {
 749         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 750         struct sk_buff *skb = NULL;
 751         struct sta_info *sta;
 752         u32 flags = 0;
 753         int ret = 0;
 754
 755         rcu_read_lock();
 756         sta = sta_info_get(sdata, peer);
 757
 758         /* infer the initiator if we can, to support old userspace */
 759         switch (action_code) {
 760         case WLAN_TDLS_SETUP_REQUEST:
 761                 if (sta) {
 762                         set_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
 763                         sta->sta.tdls_initiator = false;
 764                 }
 765                 /* fall-through */
 766         case WLAN_TDLS_SETUP_CONFIRM:
 767         case WLAN_TDLS_DISCOVERY_REQUEST:
 768                 initiator = true;
 769                 break;
 770         case WLAN_TDLS_SETUP_RESPONSE:
 771                 /*
 772                  * In some testing scenarios, we send a request and response.
 773                  * Make the last packet sent take effect for the initiator
 774                  * value.
 775                  */
 776                 if (sta) {
 777                         clear_sta_flag(sta, WLAN_STA_TDLS_INITIATOR);
 778                         sta->sta.tdls_initiator = true;
 779                 }
 780                 /* fall-through */
 781         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
 782                 initiator = false;
 783                 break;
 784         case WLAN_TDLS_TEARDOWN:
 785         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
 786         case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
 787                 /* any value is ok */
 788                 break;
 789         default:
 790                 ret = -ENOTSUPP;
 791                 break;
 792         }
 793
 794         if (sta && test_sta_flag(sta, WLAN_STA_TDLS_INITIATOR))
 795                 initiator = true;
 796
 797         rcu_read_unlock();
 798         if (ret < 0)
 799                 goto fail;
 800
 801         skb = ieee80211_tdls_build_mgmt_packet_data(sdata, peer, action_code,
 802                                                     dialog_token, status_code,
 803                                                     initiator, extra_ies,
 804                                                     extra_ies_len, oper_class,
 805                                                     chandef);
 806         if (!skb) {
 807                 ret = -EINVAL;
 808                 goto fail;
 809         }
 810
 811         if (action_code == WLAN_PUB_ACTION_TDLS_DISCOVER_RES) {
 812                 ieee80211_tx_skb(sdata, skb);
 813                 return 0;
 814         }
 815
 816         /*
 817          * According to 802.11z: Setup req/resp are sent in AC_BK, otherwise
 818          * we should default to AC_VI.
 819          */
 820         switch (action_code) {
 821         case WLAN_TDLS_SETUP_REQUEST:
 822         case WLAN_TDLS_SETUP_RESPONSE:
 823                 skb_set_queue_mapping(skb, IEEE80211_AC_BK);
 824                 skb->priority = 2;
 825                 break;
 826         default:
 827                 skb_set_queue_mapping(skb, IEEE80211_AC_VI);
 828                 skb->priority = 5;
 829                 break;
 830         }
 831
 832         /*
 833          * Set the WLAN_TDLS_TEARDOWN flag to indicate a teardown in progress.
 834          * Later, if no ACK is returned from peer, we will re-send the teardown
 835          * packet through the AP.
 836          */
 837         if ((action_code == WLAN_TDLS_TEARDOWN) &&
 838             (sdata->local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS)) {
 839                 struct sta_info *sta = NULL;
 840                 bool try_resend; /* Should we keep skb for possible resend */
 841
 842                 /* If not sending directly to peer - no point in keeping skb */
 843                 rcu_read_lock();
 844                 sta = sta_info_get(sdata, peer);
 845                 try_resend = sta && test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
 846                 rcu_read_unlock();
 847
 848                 spin_lock_bh(&sdata->u.mgd.teardown_lock);
 849                 if (try_resend && !sdata->u.mgd.teardown_skb) {
 850                         /* Mark it as requiring TX status callback  */
 851                         flags |= IEEE80211_TX_CTL_REQ_TX_STATUS |
 852                                  IEEE80211_TX_INTFL_MLME_CONN_TX;
 853
 854                         /*
 855                          * skb is copied since mac80211 will later set
 856                          * properties that might not be the same as the AP,
 857                          * such as encryption, QoS, addresses, etc.
 858                          *
 859                          * No problem if skb_copy() fails, so no need to check.
 860                          */
 861                         sdata->u.mgd.teardown_skb = skb_copy(skb, GFP_ATOMIC);
 862                         sdata->u.mgd.orig_teardown_skb = skb;
 863                 }
 864                 spin_unlock_bh(&sdata->u.mgd.teardown_lock);
 865         }
 866
 867         /* disable bottom halves when entering the Tx path */
 868         local_bh_disable();
 869         __ieee80211_subif_start_xmit(skb, dev, flags);
 870         local_bh_enable();
 871
 872         return ret;
 873
 874 fail:
 875         dev_kfree_skb(skb);
 876         return ret;
 877 }
 878
 879 static int
 880 ieee80211_tdls_mgmt_setup(struct wiphy *wiphy, struct net_device *dev,
 881                           const u8 *peer, u8 action_code, u8 dialog_token,
 882                           u16 status_code, u32 peer_capability, bool initiator,
 883                           const u8 *extra_ies, size_t extra_ies_len)
 884 {
 885         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 886         struct ieee80211_local *local = sdata->local;
 887         int ret;
 888
 889         mutex_lock(&local->mtx);
 890
 891         /* we don't support concurrent TDLS peer setups */
 892         if (!is_zero_ether_addr(sdata->u.mgd.tdls_peer) &&
 893             !ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
 894                 ret = -EBUSY;
 895                 goto exit;
 896         }
 897
 898         /*
 899          * make sure we have a STA representing the peer so we drop or buffer
 900          * non-TDLS-setup frames to the peer. We can't send other packets
 901          * during setup through the AP path.
 902          * Allow error packets to be sent - sometimes we don't even add a STA
 903          * before failing the setup.
 904          */
 905         if (status_code == 0) {
 906                 rcu_read_lock();
 907                 if (!sta_info_get(sdata, peer)) {
 908                         rcu_read_unlock();
 909                         ret = -ENOLINK;
 910                         goto exit;
 911                 }
 912                 rcu_read_unlock();
 913         }
 914
 915         ieee80211_flush_queues(local, sdata);
 916
 917         ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
 918                                               dialog_token, status_code,
 919                                               peer_capability, initiator,
 920                                               extra_ies, extra_ies_len, 0,
 921                                               NULL);
 922         if (ret < 0)
 923                 goto exit;
 924
 925         memcpy(sdata->u.mgd.tdls_peer, peer, ETH_ALEN);
 926         ieee80211_queue_delayed_work(&sdata->local->hw,
 927                                      &sdata->u.mgd.tdls_peer_del_work,
 928                                      TDLS_PEER_SETUP_TIMEOUT);
 929
 930 exit:
 931         mutex_unlock(&local->mtx);
 932         return ret;
 933 }
 934
 935 static int
 936 ieee80211_tdls_mgmt_teardown(struct wiphy *wiphy, struct net_device *dev,
 937                              const u8 *peer, u8 action_code, u8 dialog_token,
 938                              u16 status_code, u32 peer_capability,
 939                              bool initiator, const u8 *extra_ies,
 940                              size_t extra_ies_len)
 941 {
 942         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 943         struct ieee80211_local *local = sdata->local;
 944         struct sta_info *sta;
 945         int ret;
 946
 947         /*
 948          * No packets can be transmitted to the peer via the AP during setup -
 949          * the STA is set as a TDLS peer, but is not authorized.
 950          * During teardown, we prevent direct transmissions by stopping the
 951          * queues and flushing all direct packets.
 952          */
 953         ieee80211_stop_vif_queues(local, sdata,
 954                                   IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
 955         ieee80211_flush_queues(local, sdata);
 956
 957         ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, action_code,
 958                                               dialog_token, status_code,
 959                                               peer_capability, initiator,
 960                                               extra_ies, extra_ies_len, 0,
 961                                               NULL);
 962         if (ret < 0)
 963                 sdata_err(sdata, "Failed sending TDLS teardown packet %d\n",
 964                           ret);
 965
 966         /*
 967          * Remove the STA AUTH flag to force further traffic through the AP. If
 968          * the STA was unreachable, it was already removed.
 969          */
 970         rcu_read_lock();
 971         sta = sta_info_get(sdata, peer);
 972         if (sta)
 973                 clear_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
 974         rcu_read_unlock();
 975
 976         ieee80211_wake_vif_queues(local, sdata,
 977                                   IEEE80211_QUEUE_STOP_REASON_TDLS_TEARDOWN);
 978
 979         return 0;
 980 }
 981
 982 int ieee80211_tdls_mgmt(struct wiphy *wiphy, struct net_device *dev,
 983                         const u8 *peer, u8 action_code, u8 dialog_token,
 984                         u16 status_code, u32 peer_capability,
 985                         bool initiator, const u8 *extra_ies,
 986                         size_t extra_ies_len)
 987 {
 988         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 989         int ret;
 990
 991         if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
 992                 return -ENOTSUPP;
 993
 994         /* make sure we are in managed mode, and associated */
 995         if (sdata->vif.type != NL80211_IFTYPE_STATION ||
 996             !sdata->u.mgd.associated)
 997                 return -EINVAL;
 998
 999         switch (action_code) {
1000         case WLAN_TDLS_SETUP_REQUEST:
1001         case WLAN_TDLS_SETUP_RESPONSE:
1002                 ret = ieee80211_tdls_mgmt_setup(wiphy, dev, peer, action_code,
1003                                                 dialog_token, status_code,
1004                                                 peer_capability, initiator,
1005                                                 extra_ies, extra_ies_len);
1006                 break;
1007         case WLAN_TDLS_TEARDOWN:
1008                 ret = ieee80211_tdls_mgmt_teardown(wiphy, dev, peer,
1009                                                    action_code, dialog_token,
1010                                                    status_code,
1011                                                    peer_capability, initiator,
1012                                                    extra_ies, extra_ies_len);
1013                 break;
1014         case WLAN_TDLS_DISCOVERY_REQUEST:
1015                 /*
1016                  * Protect the discovery so we can hear the TDLS discovery
1017                  * response frame. It is transmitted directly and not buffered
1018                  * by the AP.
1019                  */
1020                 drv_mgd_protect_tdls_discover(sdata->local, sdata);
1021                 /* fall-through */
1022         case WLAN_TDLS_SETUP_CONFIRM:
1023         case WLAN_PUB_ACTION_TDLS_DISCOVER_RES:
1024                 /* no special handling */
1025                 ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer,
1026                                                       action_code,
1027                                                       dialog_token,
1028                                                       status_code,
1029                                                       peer_capability,
1030                                                       initiator, extra_ies,
1031                                                       extra_ies_len, 0, NULL);
1032                 break;
1033         default:
1034                 ret = -EOPNOTSUPP;
1035                 break;
1036         }
1037
1038         tdls_dbg(sdata, "TDLS mgmt action %d peer %pM status %d\n",
1039                  action_code, peer, ret);
1040         return ret;
1041 }
1042
1043 int ieee80211_tdls_oper(struct wiphy *wiphy, struct net_device *dev,
1044                         const u8 *peer, enum nl80211_tdls_operation oper)
1045 {
1046         struct sta_info *sta;
1047         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1048         struct ieee80211_local *local = sdata->local;
1049         int ret;
1050
1051         if (!(wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS))
1052                 return -ENOTSUPP;
1053
1054         if (sdata->vif.type != NL80211_IFTYPE_STATION)
1055                 return -EINVAL;
1056
1057         switch (oper) {
1058         case NL80211_TDLS_ENABLE_LINK:
1059         case NL80211_TDLS_DISABLE_LINK:
1060                 break;
1061         case NL80211_TDLS_TEARDOWN:
1062         case NL80211_TDLS_SETUP:
1063         case NL80211_TDLS_DISCOVERY_REQ:
1064                 /* We don't support in-driver setup/teardown/discovery */
1065                 return -ENOTSUPP;
1066         }
1067
1068         mutex_lock(&local->mtx);
1069         tdls_dbg(sdata, "TDLS oper %d peer %pM\n", oper, peer);
1070
1071         switch (oper) {
1072         case NL80211_TDLS_ENABLE_LINK:
1073                 rcu_read_lock();
1074                 sta = sta_info_get(sdata, peer);
1075                 if (!sta) {
1076                         rcu_read_unlock();
1077                         ret = -ENOLINK;
1078                         break;
1079                 }
1080
1081                 set_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
1082                 rcu_read_unlock();
1083
1084                 WARN_ON_ONCE(is_zero_ether_addr(sdata->u.mgd.tdls_peer) ||
1085                              !ether_addr_equal(sdata->u.mgd.tdls_peer, peer));
1086                 ret = 0;
1087                 break;
1088         case NL80211_TDLS_DISABLE_LINK:
1089                 /*
1090                  * The teardown message in ieee80211_tdls_mgmt_teardown() was
1091                  * created while the queues were stopped, so it might still be
1092                  * pending. Before flushing the queues we need to be sure the
1093                  * message is handled by the tasklet handling pending messages,
1094                  * otherwise we might start destroying the station before
1095                  * sending the teardown packet.
1096                  * Note that this only forces the tasklet to flush pendings -
1097                  * not to stop the tasklet from rescheduling itself.
1098                  */
1099                 tasklet_kill(&local->tx_pending_tasklet);
1100                 /* flush a potentially queued teardown packet */
1101                 ieee80211_flush_queues(local, sdata);
1102
1103                 ret = sta_info_destroy_addr(sdata, peer);
1104                 break;
1105         default:
1106                 ret = -ENOTSUPP;
1107                 break;
1108         }
1109
1110         if (ret == 0 && ether_addr_equal(sdata->u.mgd.tdls_peer, peer)) {
1111                 cancel_delayed_work(&sdata->u.mgd.tdls_peer_del_work);
1112                 eth_zero_addr(sdata->u.mgd.tdls_peer);
1113         }
1114
1115         mutex_unlock(&local->mtx);
1116         return ret;
1117 }
1118
1119 void ieee80211_tdls_oper_request(struct ieee80211_vif *vif, const u8 *peer,
1120                                  enum nl80211_tdls_operation oper,
1121                                  u16 reason_code, gfp_t gfp)
1122 {
1123         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1124
1125         if (vif->type != NL80211_IFTYPE_STATION || !vif->bss_conf.assoc) {
1126                 sdata_err(sdata, "Discarding TDLS oper %d - not STA or disconnected\n",
1127                           oper);
1128                 return;
1129         }
1130
1131         cfg80211_tdls_oper_request(sdata->dev, peer, oper, reason_code, gfp);
1132 }
1133 EXPORT_SYMBOL(ieee80211_tdls_oper_request);
1134
1135 static void
1136 iee80211_tdls_add_ch_switch_timing(u8 *buf, u16 switch_time, u16 switch_timeout)
1137 {
1138         struct ieee80211_ch_switch_timing *ch_sw;
1139
1140         *buf++ = WLAN_EID_CHAN_SWITCH_TIMING;
1141         *buf++ = sizeof(struct ieee80211_ch_switch_timing);
1142
1143         ch_sw = (void *)buf;
1144         ch_sw->switch_time = cpu_to_le16(switch_time);
1145         ch_sw->switch_timeout = cpu_to_le16(switch_timeout);
1146 }
1147
1148 /* find switch timing IE in SKB ready for Tx */
1149 static const u8 *ieee80211_tdls_find_sw_timing_ie(struct sk_buff *skb)
1150 {
1151         struct ieee80211_tdls_data *tf;
1152         const u8 *ie_start;
1153
1154         /*
1155          * Get the offset for the new location of the switch timing IE.
1156          * The SKB network header will now point to the "payload_type"
1157          * element of the TDLS data frame struct.
1158          */
1159         tf = container_of(skb->data + skb_network_offset(skb),
1160                           struct ieee80211_tdls_data, payload_type);
1161         ie_start = tf->u.chan_switch_req.variable;
1162         return cfg80211_find_ie(WLAN_EID_CHAN_SWITCH_TIMING, ie_start,
1163                                 skb->len - (ie_start - skb->data));
1164 }
1165
1166 static struct sk_buff *
1167 ieee80211_tdls_ch_sw_tmpl_get(struct sta_info *sta, u8 oper_class,
1168                               struct cfg80211_chan_def *chandef,
1169                               u32 *ch_sw_tm_ie_offset)
1170 {
1171         struct ieee80211_sub_if_data *sdata = sta->sdata;
1172         u8 extra_ies[2 + sizeof(struct ieee80211_sec_chan_offs_ie) +
1173                      2 + sizeof(struct ieee80211_ch_switch_timing)];
1174         int extra_ies_len = 2 + sizeof(struct ieee80211_ch_switch_timing);
1175         u8 *pos = extra_ies;
1176         struct sk_buff *skb;
1177
1178         /*
1179          * if chandef points to a wide channel add a Secondary-Channel
1180          * Offset information element
1181          */
1182         if (chandef->width == NL80211_CHAN_WIDTH_40) {
1183                 struct ieee80211_sec_chan_offs_ie *sec_chan_ie;
1184                 bool ht40plus;
1185
1186                 *pos++ = WLAN_EID_SECONDARY_CHANNEL_OFFSET;
1187                 *pos++ = sizeof(*sec_chan_ie);
1188                 sec_chan_ie = (void *)pos;
1189
1190                 ht40plus = cfg80211_get_chandef_type(chandef) ==
1191                                                         NL80211_CHAN_HT40PLUS;
1192                 sec_chan_ie->sec_chan_offs = ht40plus ?
1193                                              IEEE80211_HT_PARAM_CHA_SEC_ABOVE :
1194                                              IEEE80211_HT_PARAM_CHA_SEC_BELOW;
1195                 pos += sizeof(*sec_chan_ie);
1196
1197                 extra_ies_len += 2 + sizeof(struct ieee80211_sec_chan_offs_ie);
1198         }
1199
1200         /* just set the values to 0, this is a template */
1201         iee80211_tdls_add_ch_switch_timing(pos, 0, 0);
1202
1203         skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1204                                               WLAN_TDLS_CHANNEL_SWITCH_REQUEST,
1205                                               0, 0, !sta->sta.tdls_initiator,
1206                                               extra_ies, extra_ies_len,
1207                                               oper_class, chandef);
1208         if (!skb)
1209                 return NULL;
1210
1211         skb = ieee80211_build_data_template(sdata, skb, 0);
1212         if (IS_ERR(skb)) {
1213                 tdls_dbg(sdata, "Failed building TDLS channel switch frame\n");
1214                 return NULL;
1215         }
1216
1217         if (ch_sw_tm_ie_offset) {
1218                 const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1219
1220                 if (!tm_ie) {
1221                         tdls_dbg(sdata, "No switch timing IE in TDLS switch\n");
1222                         dev_kfree_skb_any(skb);
1223                         return NULL;
1224                 }
1225
1226                 *ch_sw_tm_ie_offset = tm_ie - skb->data;
1227         }
1228
1229         tdls_dbg(sdata,
1230                  "TDLS channel switch request template for %pM ch %d width %d\n",
1231                  sta->sta.addr, chandef->chan->center_freq, chandef->width);
1232         return skb;
1233 }
1234
1235 int
1236 ieee80211_tdls_channel_switch(struct wiphy *wiphy, struct net_device *dev,
1237                               const u8 *addr, u8 oper_class,
1238                               struct cfg80211_chan_def *chandef)
1239 {
1240         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1241         struct ieee80211_local *local = sdata->local;
1242         struct sta_info *sta;
1243         struct sk_buff *skb = NULL;
1244         u32 ch_sw_tm_ie;
1245         int ret;
1246
1247         mutex_lock(&local->sta_mtx);
1248         sta = sta_info_get(sdata, addr);
1249         if (!sta) {
1250                 tdls_dbg(sdata,
1251                          "Invalid TDLS peer %pM for channel switch request\n",
1252                          addr);
1253                 ret = -ENOENT;
1254                 goto out;
1255         }
1256
1257         if (!test_sta_flag(sta, WLAN_STA_TDLS_CHAN_SWITCH)) {
1258                 tdls_dbg(sdata, "TDLS channel switch unsupported by %pM\n",
1259                          addr);
1260                 ret = -ENOTSUPP;
1261                 goto out;
1262         }
1263
1264         skb = ieee80211_tdls_ch_sw_tmpl_get(sta, oper_class, chandef,
1265                                             &ch_sw_tm_ie);
1266         if (!skb) {
1267                 ret = -ENOENT;
1268                 goto out;
1269         }
1270
1271         ret = drv_tdls_channel_switch(local, sdata, &sta->sta, oper_class,
1272                                       chandef, skb, ch_sw_tm_ie);
1273         if (!ret)
1274                 set_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1275
1276 out:
1277         mutex_unlock(&local->sta_mtx);
1278         dev_kfree_skb_any(skb);
1279         return ret;
1280 }
1281
1282 void
1283 ieee80211_tdls_cancel_channel_switch(struct wiphy *wiphy,
1284                                      struct net_device *dev,
1285                                      const u8 *addr)
1286 {
1287         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1288         struct ieee80211_local *local = sdata->local;
1289         struct sta_info *sta;
1290
1291         mutex_lock(&local->sta_mtx);
1292         sta = sta_info_get(sdata, addr);
1293         if (!sta) {
1294                 tdls_dbg(sdata,
1295                          "Invalid TDLS peer %pM for channel switch cancel\n",
1296                          addr);
1297                 goto out;
1298         }
1299
1300         if (!test_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL)) {
1301                 tdls_dbg(sdata, "TDLS channel switch not initiated by %pM\n",
1302                          addr);
1303                 goto out;
1304         }
1305
1306         drv_tdls_cancel_channel_switch(local, sdata, &sta->sta);
1307         clear_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1308
1309 out:
1310         mutex_unlock(&local->sta_mtx);
1311 }
1312
1313 static struct sk_buff *
1314 ieee80211_tdls_ch_sw_resp_tmpl_get(struct sta_info *sta,
1315                                    u32 *ch_sw_tm_ie_offset)
1316 {
1317         struct ieee80211_sub_if_data *sdata = sta->sdata;
1318         struct sk_buff *skb;
1319         u8 extra_ies[2 + sizeof(struct ieee80211_ch_switch_timing)];
1320
1321         /* initial timing are always zero in the template */
1322         iee80211_tdls_add_ch_switch_timing(extra_ies, 0, 0);
1323
1324         skb = ieee80211_tdls_build_mgmt_packet_data(sdata, sta->sta.addr,
1325                                         WLAN_TDLS_CHANNEL_SWITCH_RESPONSE,
1326                                         0, 0, !sta->sta.tdls_initiator,
1327                                         extra_ies, sizeof(extra_ies), 0, NULL);
1328         if (!skb)
1329                 return NULL;
1330
1331         skb = ieee80211_build_data_template(sdata, skb, 0);
1332         if (IS_ERR(skb)) {
1333                 tdls_dbg(sdata,
1334                          "Failed building TDLS channel switch resp frame\n");
1335                 return NULL;
1336         }
1337
1338         if (ch_sw_tm_ie_offset) {
1339                 const u8 *tm_ie = ieee80211_tdls_find_sw_timing_ie(skb);
1340
1341                 if (!tm_ie) {
1342                         tdls_dbg(sdata,
1343                                  "No switch timing IE in TDLS switch resp\n");
1344                         dev_kfree_skb_any(skb);
1345                         return NULL;
1346                 }
1347
1348                 *ch_sw_tm_ie_offset = tm_ie - skb->data;
1349         }
1350
1351         tdls_dbg(sdata, "TDLS get channel switch response template for %pM\n",
1352                  sta->sta.addr);
1353         return skb;
1354 }
1355
1356 static int
1357 ieee80211_process_tdls_channel_switch_resp(struct ieee80211_sub_if_data *sdata,
1358                                            struct sk_buff *skb)
1359 {
1360         struct ieee80211_local *local = sdata->local;
1361         struct ieee802_11_elems elems;
1362         struct sta_info *sta;
1363         struct ieee80211_tdls_data *tf = (void *)skb->data;
1364         bool local_initiator;
1365         struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1366         int baselen = offsetof(typeof(*tf), u.chan_switch_resp.variable);
1367         struct ieee80211_tdls_ch_sw_params params = {};
1368         int ret;
1369
1370         params.action_code = WLAN_TDLS_CHANNEL_SWITCH_RESPONSE;
1371         params.timestamp = rx_status->device_timestamp;
1372
1373         if (skb->len < baselen) {
1374                 tdls_dbg(sdata, "TDLS channel switch resp too short: %d\n",
1375                          skb->len);
1376                 return -EINVAL;
1377         }
1378
1379         mutex_lock(&local->sta_mtx);
1380         sta = sta_info_get(sdata, tf->sa);
1381         if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1382                 tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1383                          tf->sa);
1384                 ret = -EINVAL;
1385                 goto out;
1386         }
1387
1388         params.sta = &sta->sta;
1389         params.status = le16_to_cpu(tf->u.chan_switch_resp.status_code);
1390         if (params.status != 0) {
1391                 ret = 0;
1392                 goto call_drv;
1393         }
1394
1395         ieee802_11_parse_elems(tf->u.chan_switch_resp.variable,
1396                                skb->len - baselen, false, &elems);
1397         if (elems.parse_error) {
1398                 tdls_dbg(sdata, "Invalid IEs in TDLS channel switch resp\n");
1399                 ret = -EINVAL;
1400                 goto out;
1401         }
1402
1403         if (!elems.ch_sw_timing || !elems.lnk_id) {
1404                 tdls_dbg(sdata, "TDLS channel switch resp - missing IEs\n");
1405                 ret = -EINVAL;
1406                 goto out;
1407         }
1408
1409         /* validate the initiator is set correctly */
1410         local_initiator =
1411                 !memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1412         if (local_initiator == sta->sta.tdls_initiator) {
1413                 tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1414                 ret = -EINVAL;
1415                 goto out;
1416         }
1417
1418         params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1419         params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1420
1421         params.tmpl_skb =
1422                 ieee80211_tdls_ch_sw_resp_tmpl_get(sta, &params.ch_sw_tm_ie);
1423         if (!params.tmpl_skb) {
1424                 ret = -ENOENT;
1425                 goto out;
1426         }
1427
1428 call_drv:
1429         drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1430
1431         tdls_dbg(sdata,
1432                  "TDLS channel switch response received from %pM status %d\n",
1433                  tf->sa, params.status);
1434
1435 out:
1436         mutex_unlock(&local->sta_mtx);
1437         dev_kfree_skb_any(params.tmpl_skb);
1438         return ret;
1439 }
1440
1441 static int
1442 ieee80211_process_tdls_channel_switch_req(struct ieee80211_sub_if_data *sdata,
1443                                           struct sk_buff *skb)
1444 {
1445         struct ieee80211_local *local = sdata->local;
1446         struct ieee802_11_elems elems;
1447         struct cfg80211_chan_def chandef;
1448         struct ieee80211_channel *chan;
1449         enum nl80211_channel_type chan_type;
1450         int freq;
1451         u8 target_channel, oper_class;
1452         bool local_initiator;
1453         struct sta_info *sta;
1454         enum ieee80211_band band;
1455         struct ieee80211_tdls_data *tf = (void *)skb->data;
1456         struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
1457         int baselen = offsetof(typeof(*tf), u.chan_switch_req.variable);
1458         struct ieee80211_tdls_ch_sw_params params = {};
1459         int ret = 0;
1460
1461         params.action_code = WLAN_TDLS_CHANNEL_SWITCH_REQUEST;
1462         params.timestamp = rx_status->device_timestamp;
1463
1464         if (skb->len < baselen) {
1465                 tdls_dbg(sdata, "TDLS channel switch req too short: %d\n",
1466                          skb->len);
1467                 return -EINVAL;
1468         }
1469
1470         target_channel = tf->u.chan_switch_req.target_channel;
1471         oper_class = tf->u.chan_switch_req.oper_class;
1472
1473         /*
1474          * We can't easily infer the channel band. The operating class is
1475          * ambiguous - there are multiple tables (US/Europe/JP/Global). The
1476          * solution here is to treat channels with number >14 as 5GHz ones,
1477          * and specifically check for the (oper_class, channel) combinations
1478          * where this doesn't hold. These are thankfully unique according to
1479          * IEEE802.11-2012.
1480          * We consider only the 2GHz and 5GHz bands and 20MHz+ channels as
1481          * valid here.
1482          */
1483         if ((oper_class == 112 || oper_class == 2 || oper_class == 3 ||
1484              oper_class == 4 || oper_class == 5 || oper_class == 6) &&
1485              target_channel < 14)
1486                 band = IEEE80211_BAND_5GHZ;
1487         else
1488                 band = target_channel < 14 ? IEEE80211_BAND_2GHZ :
1489                                              IEEE80211_BAND_5GHZ;
1490
1491         freq = ieee80211_channel_to_frequency(target_channel, band);
1492         if (freq == 0) {
1493                 tdls_dbg(sdata, "Invalid channel in TDLS chan switch: %d\n",
1494                          target_channel);
1495                 return -EINVAL;
1496         }
1497
1498         chan = ieee80211_get_channel(sdata->local->hw.wiphy, freq);
1499         if (!chan) {
1500                 tdls_dbg(sdata,
1501                          "Unsupported channel for TDLS chan switch: %d\n",
1502                          target_channel);
1503                 return -EINVAL;
1504         }
1505
1506         ieee802_11_parse_elems(tf->u.chan_switch_req.variable,
1507                                skb->len - baselen, false, &elems);
1508         if (elems.parse_error) {
1509                 tdls_dbg(sdata, "Invalid IEs in TDLS channel switch req\n");
1510                 return -EINVAL;
1511         }
1512
1513         if (!elems.ch_sw_timing || !elems.lnk_id) {
1514                 tdls_dbg(sdata, "TDLS channel switch req - missing IEs\n");
1515                 return -EINVAL;
1516         }
1517
1518         mutex_lock(&local->sta_mtx);
1519         sta = sta_info_get(sdata, tf->sa);
1520         if (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH)) {
1521                 tdls_dbg(sdata, "TDLS chan switch from non-peer sta %pM\n",
1522                          tf->sa);
1523                 ret = -EINVAL;
1524                 goto out;
1525         }
1526
1527         params.sta = &sta->sta;
1528
1529         /* validate the initiator is set correctly */
1530         local_initiator =
1531                 !memcmp(elems.lnk_id->init_sta, sdata->vif.addr, ETH_ALEN);
1532         if (local_initiator == sta->sta.tdls_initiator) {
1533                 tdls_dbg(sdata, "TDLS chan switch invalid lnk-id initiator\n");
1534                 ret = -EINVAL;
1535                 goto out;
1536         }
1537
1538         if (!sta->sta.ht_cap.ht_supported) {
1539                 chan_type = NL80211_CHAN_NO_HT;
1540         } else if (!elems.sec_chan_offs) {
1541                 chan_type = NL80211_CHAN_HT20;
1542         } else {
1543                 switch (elems.sec_chan_offs->sec_chan_offs) {
1544                 case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
1545                         chan_type = NL80211_CHAN_HT40PLUS;
1546                         break;
1547                 case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
1548                         chan_type = NL80211_CHAN_HT40MINUS;
1549                         break;
1550                 default:
1551                         chan_type = NL80211_CHAN_HT20;
1552                         break;
1553                 }
1554         }
1555
1556         cfg80211_chandef_create(&chandef, chan, chan_type);
1557         params.chandef = &chandef;
1558
1559         params.switch_time = le16_to_cpu(elems.ch_sw_timing->switch_time);
1560         params.switch_timeout = le16_to_cpu(elems.ch_sw_timing->switch_timeout);
1561
1562         params.tmpl_skb =
1563                 ieee80211_tdls_ch_sw_resp_tmpl_get(sta,
1564                                                    &params.ch_sw_tm_ie);
1565         if (!params.tmpl_skb) {
1566                 ret = -ENOENT;
1567                 goto out;
1568         }
1569
1570         drv_tdls_recv_channel_switch(sdata->local, sdata, &params);
1571
1572         tdls_dbg(sdata,
1573                  "TDLS ch switch request received from %pM ch %d width %d\n",
1574                  tf->sa, params.chandef->chan->center_freq,
1575                  params.chandef->width);
1576 out:
1577         mutex_unlock(&local->sta_mtx);
1578         dev_kfree_skb_any(params.tmpl_skb);
1579         return ret;
1580 }
1581
1582 void ieee80211_process_tdls_channel_switch(struct ieee80211_sub_if_data *sdata,
1583                                            struct sk_buff *skb)
1584 {
1585         struct ieee80211_tdls_data *tf = (void *)skb->data;
1586         struct wiphy *wiphy = sdata->local->hw.wiphy;
1587
1588         /* make sure the driver supports it */
1589         if (!(wiphy->features & NL80211_FEATURE_TDLS_CHANNEL_SWITCH))
1590                 return;
1591
1592         /* we want to access the entire packet */
1593         if (skb_linearize(skb))
1594                 return;
1595         /*
1596          * The packet/size was already validated by mac80211 Rx path, only look
1597          * at the action type.
1598          */
1599         switch (tf->action_code) {
1600         case WLAN_TDLS_CHANNEL_SWITCH_REQUEST:
1601                 ieee80211_process_tdls_channel_switch_req(sdata, skb);
1602                 break;
1603         case WLAN_TDLS_CHANNEL_SWITCH_RESPONSE:
1604                 ieee80211_process_tdls_channel_switch_resp(sdata, skb);
1605                 break;
1606         default:
1607                 WARN_ON_ONCE(1);
1608                 return;
1609         }
1610 }