1 /* 2 * IBSS mode implementation 3 * Copyright 2003-2008, Jouni Malinen <j@w1.fi> 4 * Copyright 2004, Instant802 Networks, Inc. 5 * Copyright 2005, Devicescape Software, Inc. 6 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> 7 * Copyright 2007, Michael Wu <flamingice@sourmilk.net> 8 * Copyright 2009, Johannes Berg <johannes@sipsolutions.net> 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License version 2 as 12 * published by the Free Software Foundation. 13 */ 14 15 #include <linux/delay.h> 16 #include <linux/slab.h> 17 #include <linux/if_ether.h> 18 #include <linux/skbuff.h> 19 #include <linux/if_arp.h> 20 #include <linux/etherdevice.h> 21 #include <linux/rtnetlink.h> 22 #include <net/mac80211.h> 23 24 #include "ieee80211_i.h" 25 #include "driver-ops.h" 26 #include "rate.h" 27 28 #define IEEE80211_SCAN_INTERVAL (2 * HZ) 29 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ) 30 31 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ) 32 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ) 33 #define IEEE80211_IBSS_RSN_INACTIVITY_LIMIT (10 * HZ) 34 35 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128 36 37 static struct beacon_data * 38 ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata, 39 const int beacon_int, const u32 basic_rates, 40 const u16 capability, u64 tsf, 41 struct cfg80211_chan_def *chandef, 42 bool *have_higher_than_11mbit, 43 struct cfg80211_csa_settings *csa_settings) 44 { 45 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 46 struct ieee80211_local *local = sdata->local; 47 int rates_n = 0, i, ri; 48 struct ieee80211_mgmt *mgmt; 49 u8 *pos; 50 struct ieee80211_supported_band *sband; 51 u32 rate_flags, rates = 0, rates_added = 0; 52 struct beacon_data *presp; 53 int frame_len; 54 int shift; 55 56 /* Build IBSS probe response */ 57 frame_len = sizeof(struct ieee80211_hdr_3addr) + 58 12 /* struct ieee80211_mgmt.u.beacon */ + 59 2 + IEEE80211_MAX_SSID_LEN /* max SSID */ + 60 2 + 8 /* max Supported Rates */ + 61 3 /* max DS params */ + 62 4 /* IBSS params */ + 63 5 /* Channel Switch Announcement */ + 64 2 + (IEEE80211_MAX_SUPP_RATES - 8) + 65 2 + sizeof(struct ieee80211_ht_cap) + 66 2 + sizeof(struct ieee80211_ht_operation) + 67 ifibss->ie_len; 68 presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL); 69 if (!presp) 70 return NULL; 71 72 presp->head = (void *)(presp + 1); 73 74 mgmt = (void *) presp->head; 75 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 76 IEEE80211_STYPE_PROBE_RESP); 77 eth_broadcast_addr(mgmt->da); 78 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 79 memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN); 80 mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int); 81 mgmt->u.beacon.timestamp = cpu_to_le64(tsf); 82 mgmt->u.beacon.capab_info = cpu_to_le16(capability); 83 84 pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable); 85 86 *pos++ = WLAN_EID_SSID; 87 *pos++ = ifibss->ssid_len; 88 memcpy(pos, ifibss->ssid, ifibss->ssid_len); 89 pos += ifibss->ssid_len; 90 91 sband = local->hw.wiphy->bands[chandef->chan->band]; 92 rate_flags = ieee80211_chandef_rate_flags(chandef); 93 shift = ieee80211_chandef_get_shift(chandef); 94 rates_n = 0; 95 if (have_higher_than_11mbit) 96 *have_higher_than_11mbit = false; 97 98 for (i = 0; i < sband->n_bitrates; i++) { 99 if ((rate_flags & sband->bitrates[i].flags) != rate_flags) 100 continue; 101 if (sband->bitrates[i].bitrate > 110 && 102 have_higher_than_11mbit) 103 *have_higher_than_11mbit = true; 104 105 rates |= BIT(i); 106 rates_n++; 107 } 108 109 *pos++ = WLAN_EID_SUPP_RATES; 110 *pos++ = min_t(int, 8, rates_n); 111 for (ri = 0; ri < sband->n_bitrates; ri++) { 112 int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate, 113 5 * (1 << shift)); 114 u8 basic = 0; 115 if (!(rates & BIT(ri))) 116 continue; 117 118 if (basic_rates & BIT(ri)) 119 basic = 0x80; 120 *pos++ = basic | (u8) rate; 121 if (++rates_added == 8) { 122 ri++; /* continue at next rate for EXT_SUPP_RATES */ 123 break; 124 } 125 } 126 127 if (sband->band == IEEE80211_BAND_2GHZ) { 128 *pos++ = WLAN_EID_DS_PARAMS; 129 *pos++ = 1; 130 *pos++ = ieee80211_frequency_to_channel( 131 chandef->chan->center_freq); 132 } 133 134 *pos++ = WLAN_EID_IBSS_PARAMS; 135 *pos++ = 2; 136 /* FIX: set ATIM window based on scan results */ 137 *pos++ = 0; 138 *pos++ = 0; 139 140 if (csa_settings) { 141 *pos++ = WLAN_EID_CHANNEL_SWITCH; 142 *pos++ = 3; 143 *pos++ = csa_settings->block_tx ? 1 : 0; 144 *pos++ = ieee80211_frequency_to_channel( 145 csa_settings->chandef.chan->center_freq); 146 sdata->csa_counter_offset_beacon = (pos - presp->head); 147 *pos++ = csa_settings->count; 148 } 149 150 /* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */ 151 if (rates_n > 8) { 152 *pos++ = WLAN_EID_EXT_SUPP_RATES; 153 *pos++ = rates_n - 8; 154 for (; ri < sband->n_bitrates; ri++) { 155 int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate, 156 5 * (1 << shift)); 157 u8 basic = 0; 158 if (!(rates & BIT(ri))) 159 continue; 160 161 if (basic_rates & BIT(ri)) 162 basic = 0x80; 163 *pos++ = basic | (u8) rate; 164 } 165 } 166 167 if (ifibss->ie_len) { 168 memcpy(pos, ifibss->ie, ifibss->ie_len); 169 pos += ifibss->ie_len; 170 } 171 172 /* add HT capability and information IEs */ 173 if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT && 174 chandef->width != NL80211_CHAN_WIDTH_5 && 175 chandef->width != NL80211_CHAN_WIDTH_10 && 176 sband->ht_cap.ht_supported) { 177 struct ieee80211_sta_ht_cap ht_cap; 178 179 memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap)); 180 ieee80211_apply_htcap_overrides(sdata, &ht_cap); 181 182 pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap); 183 /* 184 * Note: According to 802.11n-2009 9.13.3.1, HT Protection 185 * field and RIFS Mode are reserved in IBSS mode, therefore 186 * keep them at 0 187 */ 188 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap, 189 chandef, 0); 190 } 191 192 if (local->hw.queues >= IEEE80211_NUM_ACS) { 193 *pos++ = WLAN_EID_VENDOR_SPECIFIC; 194 *pos++ = 7; /* len */ 195 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */ 196 *pos++ = 0x50; 197 *pos++ = 0xf2; 198 *pos++ = 2; /* WME */ 199 *pos++ = 0; /* WME info */ 200 *pos++ = 1; /* WME ver */ 201 *pos++ = 0; /* U-APSD no in use */ 202 } 203 204 presp->head_len = pos - presp->head; 205 if (WARN_ON(presp->head_len > frame_len)) 206 goto error; 207 208 return presp; 209 error: 210 kfree(presp); 211 return NULL; 212 } 213 214 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 215 const u8 *bssid, const int beacon_int, 216 struct cfg80211_chan_def *req_chandef, 217 const u32 basic_rates, 218 const u16 capability, u64 tsf, 219 bool creator) 220 { 221 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 222 struct ieee80211_local *local = sdata->local; 223 struct ieee80211_mgmt *mgmt; 224 struct cfg80211_bss *bss; 225 u32 bss_change; 226 struct cfg80211_chan_def chandef; 227 struct ieee80211_channel *chan; 228 struct beacon_data *presp; 229 enum nl80211_bss_scan_width scan_width; 230 bool have_higher_than_11mbit; 231 bool radar_required = false; 232 int err; 233 234 sdata_assert_lock(sdata); 235 236 /* Reset own TSF to allow time synchronization work. */ 237 drv_reset_tsf(local, sdata); 238 239 if (!ether_addr_equal(ifibss->bssid, bssid)) 240 sta_info_flush(sdata); 241 242 /* if merging, indicate to driver that we leave the old IBSS */ 243 if (sdata->vif.bss_conf.ibss_joined) { 244 sdata->vif.bss_conf.ibss_joined = false; 245 sdata->vif.bss_conf.ibss_creator = false; 246 sdata->vif.bss_conf.enable_beacon = false; 247 netif_carrier_off(sdata->dev); 248 ieee80211_bss_info_change_notify(sdata, 249 BSS_CHANGED_IBSS | 250 BSS_CHANGED_BEACON_ENABLED); 251 drv_leave_ibss(local, sdata); 252 } 253 254 presp = rcu_dereference_protected(ifibss->presp, 255 lockdep_is_held(&sdata->wdev.mtx)); 256 rcu_assign_pointer(ifibss->presp, NULL); 257 if (presp) 258 kfree_rcu(presp, rcu_head); 259 260 sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0; 261 262 /* make a copy of the chandef, it could be modified below. */ 263 chandef = *req_chandef; 264 chan = chandef.chan; 265 if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) { 266 if (chandef.width == NL80211_CHAN_WIDTH_5 || 267 chandef.width == NL80211_CHAN_WIDTH_10 || 268 chandef.width == NL80211_CHAN_WIDTH_20_NOHT || 269 chandef.width == NL80211_CHAN_WIDTH_20) { 270 sdata_info(sdata, 271 "Failed to join IBSS, beacons forbidden\n"); 272 return; 273 } 274 chandef.width = NL80211_CHAN_WIDTH_20; 275 chandef.center_freq1 = chan->center_freq; 276 /* check again for downgraded chandef */ 277 if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) { 278 sdata_info(sdata, 279 "Failed to join IBSS, beacons forbidden\n"); 280 return; 281 } 282 } 283 284 err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy, 285 &chandef); 286 if (err < 0) { 287 sdata_info(sdata, 288 "Failed to join IBSS, invalid chandef\n"); 289 return; 290 } 291 if (err > 0) { 292 if (!ifibss->userspace_handles_dfs) { 293 sdata_info(sdata, 294 "Failed to join IBSS, DFS channel without control program\n"); 295 return; 296 } 297 radar_required = true; 298 } 299 300 mutex_lock(&local->mtx); 301 if (ieee80211_vif_use_channel(sdata, &chandef, 302 ifibss->fixed_channel ? 303 IEEE80211_CHANCTX_SHARED : 304 IEEE80211_CHANCTX_EXCLUSIVE)) { 305 sdata_info(sdata, "Failed to join IBSS, no channel context\n"); 306 mutex_unlock(&local->mtx); 307 return; 308 } 309 sdata->radar_required = radar_required; 310 mutex_unlock(&local->mtx); 311 312 memcpy(ifibss->bssid, bssid, ETH_ALEN); 313 314 presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates, 315 capability, tsf, &chandef, 316 &have_higher_than_11mbit, NULL); 317 if (!presp) 318 return; 319 320 rcu_assign_pointer(ifibss->presp, presp); 321 mgmt = (void *)presp->head; 322 323 sdata->vif.bss_conf.enable_beacon = true; 324 sdata->vif.bss_conf.beacon_int = beacon_int; 325 sdata->vif.bss_conf.basic_rates = basic_rates; 326 sdata->vif.bss_conf.ssid_len = ifibss->ssid_len; 327 memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len); 328 bss_change = BSS_CHANGED_BEACON_INT; 329 bss_change |= ieee80211_reset_erp_info(sdata); 330 bss_change |= BSS_CHANGED_BSSID; 331 bss_change |= BSS_CHANGED_BEACON; 332 bss_change |= BSS_CHANGED_BEACON_ENABLED; 333 bss_change |= BSS_CHANGED_BASIC_RATES; 334 bss_change |= BSS_CHANGED_HT; 335 bss_change |= BSS_CHANGED_IBSS; 336 bss_change |= BSS_CHANGED_SSID; 337 338 /* 339 * In 5 GHz/802.11a, we can always use short slot time. 340 * (IEEE 802.11-2012 18.3.8.7) 341 * 342 * In 2.4GHz, we must always use long slots in IBSS for compatibility 343 * reasons. 344 * (IEEE 802.11-2012 19.4.5) 345 * 346 * HT follows these specifications (IEEE 802.11-2012 20.3.18) 347 */ 348 sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ; 349 bss_change |= BSS_CHANGED_ERP_SLOT; 350 351 /* cf. IEEE 802.11 9.2.12 */ 352 if (chan->band == IEEE80211_BAND_2GHZ && have_higher_than_11mbit) 353 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE; 354 else 355 sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE; 356 357 ieee80211_set_wmm_default(sdata, true); 358 359 sdata->vif.bss_conf.ibss_joined = true; 360 sdata->vif.bss_conf.ibss_creator = creator; 361 362 err = drv_join_ibss(local, sdata); 363 if (err) { 364 sdata->vif.bss_conf.ibss_joined = false; 365 sdata->vif.bss_conf.ibss_creator = false; 366 sdata->vif.bss_conf.enable_beacon = false; 367 sdata->vif.bss_conf.ssid_len = 0; 368 RCU_INIT_POINTER(ifibss->presp, NULL); 369 kfree_rcu(presp, rcu_head); 370 mutex_lock(&local->mtx); 371 ieee80211_vif_release_channel(sdata); 372 mutex_unlock(&local->mtx); 373 sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n", 374 err); 375 return; 376 } 377 378 ieee80211_bss_info_change_notify(sdata, bss_change); 379 380 ifibss->state = IEEE80211_IBSS_MLME_JOINED; 381 mod_timer(&ifibss->timer, 382 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 383 384 scan_width = cfg80211_chandef_to_scan_width(&chandef); 385 bss = cfg80211_inform_bss_width_frame(local->hw.wiphy, chan, 386 scan_width, mgmt, 387 presp->head_len, 0, GFP_KERNEL); 388 cfg80211_put_bss(local->hw.wiphy, bss); 389 netif_carrier_on(sdata->dev); 390 cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL); 391 } 392 393 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 394 struct ieee80211_bss *bss) 395 { 396 struct cfg80211_bss *cbss = 397 container_of((void *)bss, struct cfg80211_bss, priv); 398 struct ieee80211_supported_band *sband; 399 struct cfg80211_chan_def chandef; 400 u32 basic_rates; 401 int i, j; 402 u16 beacon_int = cbss->beacon_interval; 403 const struct cfg80211_bss_ies *ies; 404 enum nl80211_channel_type chan_type; 405 u64 tsf; 406 u32 rate_flags; 407 int shift; 408 409 sdata_assert_lock(sdata); 410 411 if (beacon_int < 10) 412 beacon_int = 10; 413 414 switch (sdata->u.ibss.chandef.width) { 415 case NL80211_CHAN_WIDTH_20_NOHT: 416 case NL80211_CHAN_WIDTH_20: 417 case NL80211_CHAN_WIDTH_40: 418 chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef); 419 cfg80211_chandef_create(&chandef, cbss->channel, chan_type); 420 break; 421 case NL80211_CHAN_WIDTH_5: 422 case NL80211_CHAN_WIDTH_10: 423 cfg80211_chandef_create(&chandef, cbss->channel, 424 NL80211_CHAN_WIDTH_20_NOHT); 425 chandef.width = sdata->u.ibss.chandef.width; 426 break; 427 default: 428 /* fall back to 20 MHz for unsupported modes */ 429 cfg80211_chandef_create(&chandef, cbss->channel, 430 NL80211_CHAN_WIDTH_20_NOHT); 431 break; 432 } 433 434 sband = sdata->local->hw.wiphy->bands[cbss->channel->band]; 435 rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef); 436 shift = ieee80211_vif_get_shift(&sdata->vif); 437 438 basic_rates = 0; 439 440 for (i = 0; i < bss->supp_rates_len; i++) { 441 int rate = bss->supp_rates[i] & 0x7f; 442 bool is_basic = !!(bss->supp_rates[i] & 0x80); 443 444 for (j = 0; j < sband->n_bitrates; j++) { 445 int brate; 446 if ((rate_flags & sband->bitrates[j].flags) 447 != rate_flags) 448 continue; 449 450 brate = DIV_ROUND_UP(sband->bitrates[j].bitrate, 451 5 * (1 << shift)); 452 if (brate == rate) { 453 if (is_basic) 454 basic_rates |= BIT(j); 455 break; 456 } 457 } 458 } 459 460 rcu_read_lock(); 461 ies = rcu_dereference(cbss->ies); 462 tsf = ies->tsf; 463 rcu_read_unlock(); 464 465 __ieee80211_sta_join_ibss(sdata, cbss->bssid, 466 beacon_int, 467 &chandef, 468 basic_rates, 469 cbss->capability, 470 tsf, false); 471 } 472 473 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata, 474 struct cfg80211_csa_settings *csa_settings) 475 { 476 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 477 struct beacon_data *presp, *old_presp; 478 struct cfg80211_bss *cbss; 479 const struct cfg80211_bss_ies *ies; 480 u16 capability; 481 u64 tsf; 482 int ret = 0; 483 484 sdata_assert_lock(sdata); 485 486 capability = WLAN_CAPABILITY_IBSS; 487 488 if (ifibss->privacy) 489 capability |= WLAN_CAPABILITY_PRIVACY; 490 491 cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan, 492 ifibss->bssid, ifibss->ssid, 493 ifibss->ssid_len, WLAN_CAPABILITY_IBSS | 494 WLAN_CAPABILITY_PRIVACY, 495 capability); 496 497 if (WARN_ON(!cbss)) { 498 ret = -EINVAL; 499 goto out; 500 } 501 502 rcu_read_lock(); 503 ies = rcu_dereference(cbss->ies); 504 tsf = ies->tsf; 505 rcu_read_unlock(); 506 cfg80211_put_bss(sdata->local->hw.wiphy, cbss); 507 508 old_presp = rcu_dereference_protected(ifibss->presp, 509 lockdep_is_held(&sdata->wdev.mtx)); 510 511 presp = ieee80211_ibss_build_presp(sdata, 512 sdata->vif.bss_conf.beacon_int, 513 sdata->vif.bss_conf.basic_rates, 514 capability, tsf, &ifibss->chandef, 515 NULL, csa_settings); 516 if (!presp) { 517 ret = -ENOMEM; 518 goto out; 519 } 520 521 rcu_assign_pointer(ifibss->presp, presp); 522 if (old_presp) 523 kfree_rcu(old_presp, rcu_head); 524 525 return BSS_CHANGED_BEACON; 526 out: 527 return ret; 528 } 529 530 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata) 531 { 532 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 533 struct cfg80211_bss *cbss; 534 int err, changed = 0; 535 u16 capability; 536 537 sdata_assert_lock(sdata); 538 539 /* update cfg80211 bss information with the new channel */ 540 if (!is_zero_ether_addr(ifibss->bssid)) { 541 capability = WLAN_CAPABILITY_IBSS; 542 543 if (ifibss->privacy) 544 capability |= WLAN_CAPABILITY_PRIVACY; 545 546 cbss = cfg80211_get_bss(sdata->local->hw.wiphy, 547 ifibss->chandef.chan, 548 ifibss->bssid, ifibss->ssid, 549 ifibss->ssid_len, WLAN_CAPABILITY_IBSS | 550 WLAN_CAPABILITY_PRIVACY, 551 capability); 552 /* XXX: should not really modify cfg80211 data */ 553 if (cbss) { 554 cbss->channel = sdata->csa_chandef.chan; 555 cfg80211_put_bss(sdata->local->hw.wiphy, cbss); 556 } 557 } 558 559 ifibss->chandef = sdata->csa_chandef; 560 561 /* generate the beacon */ 562 err = ieee80211_ibss_csa_beacon(sdata, NULL); 563 if (err < 0) 564 return err; 565 566 changed |= err; 567 568 return changed; 569 } 570 571 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata) 572 { 573 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 574 575 cancel_work_sync(&ifibss->csa_connection_drop_work); 576 } 577 578 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta) 579 __acquires(RCU) 580 { 581 struct ieee80211_sub_if_data *sdata = sta->sdata; 582 u8 addr[ETH_ALEN]; 583 584 memcpy(addr, sta->sta.addr, ETH_ALEN); 585 586 ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr); 587 588 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH); 589 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC); 590 /* authorize the station only if the network is not RSN protected. If 591 * not wait for the userspace to authorize it */ 592 if (!sta->sdata->u.ibss.control_port) 593 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED); 594 595 rate_control_rate_init(sta); 596 597 /* If it fails, maybe we raced another insertion? */ 598 if (sta_info_insert_rcu(sta)) 599 return sta_info_get(sdata, addr); 600 return sta; 601 } 602 603 static struct sta_info * 604 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid, 605 const u8 *addr, u32 supp_rates) 606 __acquires(RCU) 607 { 608 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 609 struct ieee80211_local *local = sdata->local; 610 struct sta_info *sta; 611 struct ieee80211_chanctx_conf *chanctx_conf; 612 struct ieee80211_supported_band *sband; 613 enum nl80211_bss_scan_width scan_width; 614 int band; 615 616 /* 617 * XXX: Consider removing the least recently used entry and 618 * allow new one to be added. 619 */ 620 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 621 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n", 622 sdata->name, addr); 623 rcu_read_lock(); 624 return NULL; 625 } 626 627 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) { 628 rcu_read_lock(); 629 return NULL; 630 } 631 632 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) { 633 rcu_read_lock(); 634 return NULL; 635 } 636 637 rcu_read_lock(); 638 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); 639 if (WARN_ON_ONCE(!chanctx_conf)) 640 return NULL; 641 band = chanctx_conf->def.chan->band; 642 scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def); 643 rcu_read_unlock(); 644 645 sta = sta_info_alloc(sdata, addr, GFP_KERNEL); 646 if (!sta) { 647 rcu_read_lock(); 648 return NULL; 649 } 650 651 sta->last_rx = jiffies; 652 653 /* make sure mandatory rates are always added */ 654 sband = local->hw.wiphy->bands[band]; 655 sta->sta.supp_rates[band] = supp_rates | 656 ieee80211_mandatory_rates(sband, scan_width); 657 658 return ieee80211_ibss_finish_sta(sta); 659 } 660 661 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata) 662 { 663 struct ieee80211_local *local = sdata->local; 664 int active = 0; 665 struct sta_info *sta; 666 667 sdata_assert_lock(sdata); 668 669 rcu_read_lock(); 670 671 list_for_each_entry_rcu(sta, &local->sta_list, list) { 672 if (sta->sdata == sdata && 673 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL, 674 jiffies)) { 675 active++; 676 break; 677 } 678 } 679 680 rcu_read_unlock(); 681 682 return active; 683 } 684 685 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata) 686 { 687 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 688 struct ieee80211_local *local = sdata->local; 689 struct cfg80211_bss *cbss; 690 struct beacon_data *presp; 691 struct sta_info *sta; 692 u16 capability; 693 694 if (!is_zero_ether_addr(ifibss->bssid)) { 695 capability = WLAN_CAPABILITY_IBSS; 696 697 if (ifibss->privacy) 698 capability |= WLAN_CAPABILITY_PRIVACY; 699 700 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan, 701 ifibss->bssid, ifibss->ssid, 702 ifibss->ssid_len, WLAN_CAPABILITY_IBSS | 703 WLAN_CAPABILITY_PRIVACY, 704 capability); 705 706 if (cbss) { 707 cfg80211_unlink_bss(local->hw.wiphy, cbss); 708 cfg80211_put_bss(sdata->local->hw.wiphy, cbss); 709 } 710 } 711 712 ifibss->state = IEEE80211_IBSS_MLME_SEARCH; 713 714 sta_info_flush(sdata); 715 716 spin_lock_bh(&ifibss->incomplete_lock); 717 while (!list_empty(&ifibss->incomplete_stations)) { 718 sta = list_first_entry(&ifibss->incomplete_stations, 719 struct sta_info, list); 720 list_del(&sta->list); 721 spin_unlock_bh(&ifibss->incomplete_lock); 722 723 sta_info_free(local, sta); 724 spin_lock_bh(&ifibss->incomplete_lock); 725 } 726 spin_unlock_bh(&ifibss->incomplete_lock); 727 728 netif_carrier_off(sdata->dev); 729 730 sdata->vif.bss_conf.ibss_joined = false; 731 sdata->vif.bss_conf.ibss_creator = false; 732 sdata->vif.bss_conf.enable_beacon = false; 733 sdata->vif.bss_conf.ssid_len = 0; 734 735 /* remove beacon */ 736 presp = rcu_dereference_protected(ifibss->presp, 737 lockdep_is_held(&sdata->wdev.mtx)); 738 RCU_INIT_POINTER(sdata->u.ibss.presp, NULL); 739 if (presp) 740 kfree_rcu(presp, rcu_head); 741 742 clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state); 743 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED | 744 BSS_CHANGED_IBSS); 745 drv_leave_ibss(local, sdata); 746 mutex_lock(&local->mtx); 747 ieee80211_vif_release_channel(sdata); 748 mutex_unlock(&local->mtx); 749 } 750 751 static void ieee80211_csa_connection_drop_work(struct work_struct *work) 752 { 753 struct ieee80211_sub_if_data *sdata = 754 container_of(work, struct ieee80211_sub_if_data, 755 u.ibss.csa_connection_drop_work); 756 757 sdata_lock(sdata); 758 759 ieee80211_ibss_disconnect(sdata); 760 synchronize_rcu(); 761 skb_queue_purge(&sdata->skb_queue); 762 763 /* trigger a scan to find another IBSS network to join */ 764 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 765 766 sdata_unlock(sdata); 767 } 768 769 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata) 770 { 771 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 772 int err; 773 774 /* if the current channel is a DFS channel, mark the channel as 775 * unavailable. 776 */ 777 err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy, 778 &ifibss->chandef); 779 if (err > 0) 780 cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef, 781 GFP_ATOMIC); 782 } 783 784 static bool 785 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata, 786 struct ieee802_11_elems *elems, 787 bool beacon) 788 { 789 struct cfg80211_csa_settings params; 790 struct ieee80211_csa_ie csa_ie; 791 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 792 enum nl80211_channel_type ch_type; 793 int err; 794 u32 sta_flags; 795 796 sdata_assert_lock(sdata); 797 798 sta_flags = IEEE80211_STA_DISABLE_VHT; 799 switch (ifibss->chandef.width) { 800 case NL80211_CHAN_WIDTH_5: 801 case NL80211_CHAN_WIDTH_10: 802 case NL80211_CHAN_WIDTH_20_NOHT: 803 sta_flags |= IEEE80211_STA_DISABLE_HT; 804 /* fall through */ 805 case NL80211_CHAN_WIDTH_20: 806 sta_flags |= IEEE80211_STA_DISABLE_40MHZ; 807 break; 808 default: 809 break; 810 } 811 812 memset(¶ms, 0, sizeof(params)); 813 memset(&csa_ie, 0, sizeof(csa_ie)); 814 err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon, 815 ifibss->chandef.chan->band, 816 sta_flags, ifibss->bssid, &csa_ie); 817 /* can't switch to destination channel, fail */ 818 if (err < 0) 819 goto disconnect; 820 821 /* did not contain a CSA */ 822 if (err) 823 return false; 824 825 /* channel switch is not supported, disconnect */ 826 if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH)) 827 goto disconnect; 828 829 params.count = csa_ie.count; 830 params.chandef = csa_ie.chandef; 831 832 switch (ifibss->chandef.width) { 833 case NL80211_CHAN_WIDTH_20_NOHT: 834 case NL80211_CHAN_WIDTH_20: 835 case NL80211_CHAN_WIDTH_40: 836 /* keep our current HT mode (HT20/HT40+/HT40-), even if 837 * another mode has been announced. The mode is not adopted 838 * within the beacon while doing CSA and we should therefore 839 * keep the mode which we announce. 840 */ 841 ch_type = cfg80211_get_chandef_type(&ifibss->chandef); 842 cfg80211_chandef_create(¶ms.chandef, params.chandef.chan, 843 ch_type); 844 break; 845 case NL80211_CHAN_WIDTH_5: 846 case NL80211_CHAN_WIDTH_10: 847 if (params.chandef.width != ifibss->chandef.width) { 848 sdata_info(sdata, 849 "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n", 850 ifibss->bssid, 851 params.chandef.chan->center_freq, 852 params.chandef.width, 853 params.chandef.center_freq1, 854 params.chandef.center_freq2); 855 goto disconnect; 856 } 857 break; 858 default: 859 /* should not happen, sta_flags should prevent VHT modes. */ 860 WARN_ON(1); 861 goto disconnect; 862 } 863 864 if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, ¶ms.chandef)) { 865 sdata_info(sdata, 866 "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n", 867 ifibss->bssid, 868 params.chandef.chan->center_freq, 869 params.chandef.width, 870 params.chandef.center_freq1, 871 params.chandef.center_freq2); 872 goto disconnect; 873 } 874 875 err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy, 876 ¶ms.chandef); 877 if (err < 0) 878 goto disconnect; 879 if (err) { 880 /* IBSS-DFS only allowed with a control program */ 881 if (!ifibss->userspace_handles_dfs) 882 goto disconnect; 883 884 params.radar_required = true; 885 } 886 887 if (cfg80211_chandef_identical(¶ms.chandef, 888 &sdata->vif.bss_conf.chandef)) { 889 ibss_dbg(sdata, 890 "received csa with an identical chandef, ignoring\n"); 891 return true; 892 } 893 894 /* all checks done, now perform the channel switch. */ 895 ibss_dbg(sdata, 896 "received channel switch announcement to go to channel %d MHz\n", 897 params.chandef.chan->center_freq); 898 899 params.block_tx = !!csa_ie.mode; 900 901 if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev, 902 ¶ms)) 903 goto disconnect; 904 905 ieee80211_ibss_csa_mark_radar(sdata); 906 907 return true; 908 disconnect: 909 ibss_dbg(sdata, "Can't handle channel switch, disconnect\n"); 910 ieee80211_queue_work(&sdata->local->hw, 911 &ifibss->csa_connection_drop_work); 912 913 ieee80211_ibss_csa_mark_radar(sdata); 914 915 return true; 916 } 917 918 static void 919 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata, 920 struct ieee80211_mgmt *mgmt, size_t len, 921 struct ieee80211_rx_status *rx_status, 922 struct ieee802_11_elems *elems) 923 { 924 int required_len; 925 926 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 927 return; 928 929 /* CSA is the only action we handle for now */ 930 if (mgmt->u.action.u.measurement.action_code != 931 WLAN_ACTION_SPCT_CHL_SWITCH) 932 return; 933 934 required_len = IEEE80211_MIN_ACTION_SIZE + 935 sizeof(mgmt->u.action.u.chan_switch); 936 if (len < required_len) 937 return; 938 939 if (!sdata->vif.csa_active) 940 ieee80211_ibss_process_chanswitch(sdata, elems, false); 941 } 942 943 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata, 944 struct ieee80211_mgmt *mgmt, 945 size_t len) 946 { 947 u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code); 948 949 if (len < IEEE80211_DEAUTH_FRAME_LEN) 950 return; 951 952 ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n", 953 mgmt->sa, mgmt->da, mgmt->bssid, reason); 954 sta_info_destroy_addr(sdata, mgmt->sa); 955 } 956 957 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata, 958 struct ieee80211_mgmt *mgmt, 959 size_t len) 960 { 961 u16 auth_alg, auth_transaction; 962 963 sdata_assert_lock(sdata); 964 965 if (len < 24 + 6) 966 return; 967 968 auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg); 969 auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction); 970 971 ibss_dbg(sdata, 972 "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n", 973 mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction); 974 975 if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1) 976 return; 977 978 /* 979 * IEEE 802.11 standard does not require authentication in IBSS 980 * networks and most implementations do not seem to use it. 981 * However, try to reply to authentication attempts if someone 982 * has actually implemented this. 983 */ 984 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0, 985 mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0); 986 } 987 988 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, 989 struct ieee80211_mgmt *mgmt, size_t len, 990 struct ieee80211_rx_status *rx_status, 991 struct ieee802_11_elems *elems) 992 { 993 struct ieee80211_local *local = sdata->local; 994 struct cfg80211_bss *cbss; 995 struct ieee80211_bss *bss; 996 struct sta_info *sta; 997 struct ieee80211_channel *channel; 998 u64 beacon_timestamp, rx_timestamp; 999 u32 supp_rates = 0; 1000 enum ieee80211_band band = rx_status->band; 1001 enum nl80211_bss_scan_width scan_width; 1002 struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band]; 1003 bool rates_updated = false; 1004 1005 channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq); 1006 if (!channel) 1007 return; 1008 1009 if (sdata->vif.type == NL80211_IFTYPE_ADHOC && 1010 ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) { 1011 1012 rcu_read_lock(); 1013 sta = sta_info_get(sdata, mgmt->sa); 1014 1015 if (elems->supp_rates) { 1016 supp_rates = ieee80211_sta_get_rates(sdata, elems, 1017 band, NULL); 1018 if (sta) { 1019 u32 prev_rates; 1020 1021 prev_rates = sta->sta.supp_rates[band]; 1022 /* make sure mandatory rates are always added */ 1023 scan_width = NL80211_BSS_CHAN_WIDTH_20; 1024 if (rx_status->flag & RX_FLAG_5MHZ) 1025 scan_width = NL80211_BSS_CHAN_WIDTH_5; 1026 if (rx_status->flag & RX_FLAG_10MHZ) 1027 scan_width = NL80211_BSS_CHAN_WIDTH_10; 1028 1029 sta->sta.supp_rates[band] = supp_rates | 1030 ieee80211_mandatory_rates(sband, 1031 scan_width); 1032 if (sta->sta.supp_rates[band] != prev_rates) { 1033 ibss_dbg(sdata, 1034 "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n", 1035 sta->sta.addr, prev_rates, 1036 sta->sta.supp_rates[band]); 1037 rates_updated = true; 1038 } 1039 } else { 1040 rcu_read_unlock(); 1041 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, 1042 mgmt->sa, supp_rates); 1043 } 1044 } 1045 1046 if (sta && elems->wmm_info) 1047 set_sta_flag(sta, WLAN_STA_WME); 1048 1049 if (sta && elems->ht_operation && elems->ht_cap_elem && 1050 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT && 1051 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 && 1052 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) { 1053 /* we both use HT */ 1054 struct ieee80211_ht_cap htcap_ie; 1055 struct cfg80211_chan_def chandef; 1056 1057 ieee80211_ht_oper_to_chandef(channel, 1058 elems->ht_operation, 1059 &chandef); 1060 1061 memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie)); 1062 1063 /* 1064 * fall back to HT20 if we don't use or use 1065 * the other extension channel 1066 */ 1067 if (chandef.center_freq1 != 1068 sdata->u.ibss.chandef.center_freq1) 1069 htcap_ie.cap_info &= 1070 cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40); 1071 1072 rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap( 1073 sdata, sband, &htcap_ie, sta); 1074 } 1075 1076 if (sta && rates_updated) { 1077 drv_sta_rc_update(local, sdata, &sta->sta, 1078 IEEE80211_RC_SUPP_RATES_CHANGED); 1079 rate_control_rate_init(sta); 1080 } 1081 1082 rcu_read_unlock(); 1083 } 1084 1085 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems, 1086 channel); 1087 if (!bss) 1088 return; 1089 1090 cbss = container_of((void *)bss, struct cfg80211_bss, priv); 1091 1092 /* same for beacon and probe response */ 1093 beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp); 1094 1095 /* check if we need to merge IBSS */ 1096 1097 /* not an IBSS */ 1098 if (!(cbss->capability & WLAN_CAPABILITY_IBSS)) 1099 goto put_bss; 1100 1101 /* different channel */ 1102 if (sdata->u.ibss.fixed_channel && 1103 sdata->u.ibss.chandef.chan != cbss->channel) 1104 goto put_bss; 1105 1106 /* different SSID */ 1107 if (elems->ssid_len != sdata->u.ibss.ssid_len || 1108 memcmp(elems->ssid, sdata->u.ibss.ssid, 1109 sdata->u.ibss.ssid_len)) 1110 goto put_bss; 1111 1112 /* process channel switch */ 1113 if (sdata->vif.csa_active || 1114 ieee80211_ibss_process_chanswitch(sdata, elems, true)) 1115 goto put_bss; 1116 1117 /* same BSSID */ 1118 if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid)) 1119 goto put_bss; 1120 1121 /* we use a fixed BSSID */ 1122 if (sdata->u.ibss.fixed_bssid) 1123 goto put_bss; 1124 1125 if (ieee80211_have_rx_timestamp(rx_status)) { 1126 /* time when timestamp field was received */ 1127 rx_timestamp = 1128 ieee80211_calculate_rx_timestamp(local, rx_status, 1129 len + FCS_LEN, 24); 1130 } else { 1131 /* 1132 * second best option: get current TSF 1133 * (will return -1 if not supported) 1134 */ 1135 rx_timestamp = drv_get_tsf(local, sdata); 1136 } 1137 1138 ibss_dbg(sdata, 1139 "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n", 1140 mgmt->sa, mgmt->bssid, 1141 (unsigned long long)rx_timestamp, 1142 (unsigned long long)beacon_timestamp, 1143 (unsigned long long)(rx_timestamp - beacon_timestamp), 1144 jiffies); 1145 1146 if (beacon_timestamp > rx_timestamp) { 1147 ibss_dbg(sdata, 1148 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n", 1149 mgmt->bssid); 1150 ieee80211_sta_join_ibss(sdata, bss); 1151 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL); 1152 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 1153 supp_rates); 1154 rcu_read_unlock(); 1155 } 1156 1157 put_bss: 1158 ieee80211_rx_bss_put(local, bss); 1159 } 1160 1161 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata, 1162 const u8 *bssid, const u8 *addr, 1163 u32 supp_rates) 1164 { 1165 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1166 struct ieee80211_local *local = sdata->local; 1167 struct sta_info *sta; 1168 struct ieee80211_chanctx_conf *chanctx_conf; 1169 struct ieee80211_supported_band *sband; 1170 enum nl80211_bss_scan_width scan_width; 1171 int band; 1172 1173 /* 1174 * XXX: Consider removing the least recently used entry and 1175 * allow new one to be added. 1176 */ 1177 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 1178 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n", 1179 sdata->name, addr); 1180 return; 1181 } 1182 1183 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) 1184 return; 1185 1186 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) 1187 return; 1188 1189 rcu_read_lock(); 1190 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); 1191 if (WARN_ON_ONCE(!chanctx_conf)) { 1192 rcu_read_unlock(); 1193 return; 1194 } 1195 band = chanctx_conf->def.chan->band; 1196 scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def); 1197 rcu_read_unlock(); 1198 1199 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC); 1200 if (!sta) 1201 return; 1202 1203 sta->last_rx = jiffies; 1204 1205 /* make sure mandatory rates are always added */ 1206 sband = local->hw.wiphy->bands[band]; 1207 sta->sta.supp_rates[band] = supp_rates | 1208 ieee80211_mandatory_rates(sband, scan_width); 1209 1210 spin_lock(&ifibss->incomplete_lock); 1211 list_add(&sta->list, &ifibss->incomplete_stations); 1212 spin_unlock(&ifibss->incomplete_lock); 1213 ieee80211_queue_work(&local->hw, &sdata->work); 1214 } 1215 1216 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata) 1217 { 1218 struct ieee80211_local *local = sdata->local; 1219 struct sta_info *sta, *tmp; 1220 unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT; 1221 unsigned long exp_rsn_time = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT; 1222 1223 mutex_lock(&local->sta_mtx); 1224 1225 list_for_each_entry_safe(sta, tmp, &local->sta_list, list) { 1226 if (sdata != sta->sdata) 1227 continue; 1228 1229 if (time_after(jiffies, sta->last_rx + exp_time) || 1230 (time_after(jiffies, sta->last_rx + exp_rsn_time) && 1231 sta->sta_state != IEEE80211_STA_AUTHORIZED)) { 1232 sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n", 1233 sta->sta_state != IEEE80211_STA_AUTHORIZED ? 1234 "not authorized " : "", sta->sta.addr); 1235 1236 WARN_ON(__sta_info_destroy(sta)); 1237 } 1238 } 1239 1240 mutex_unlock(&local->sta_mtx); 1241 } 1242 1243 /* 1244 * This function is called with state == IEEE80211_IBSS_MLME_JOINED 1245 */ 1246 1247 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata) 1248 { 1249 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1250 enum nl80211_bss_scan_width scan_width; 1251 1252 sdata_assert_lock(sdata); 1253 1254 mod_timer(&ifibss->timer, 1255 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 1256 1257 ieee80211_ibss_sta_expire(sdata); 1258 1259 if (time_before(jiffies, ifibss->last_scan_completed + 1260 IEEE80211_IBSS_MERGE_INTERVAL)) 1261 return; 1262 1263 if (ieee80211_sta_active_ibss(sdata)) 1264 return; 1265 1266 if (ifibss->fixed_channel) 1267 return; 1268 1269 sdata_info(sdata, 1270 "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n"); 1271 1272 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef); 1273 ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len, 1274 NULL, scan_width); 1275 } 1276 1277 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata) 1278 { 1279 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1280 u8 bssid[ETH_ALEN]; 1281 u16 capability; 1282 int i; 1283 1284 sdata_assert_lock(sdata); 1285 1286 if (ifibss->fixed_bssid) { 1287 memcpy(bssid, ifibss->bssid, ETH_ALEN); 1288 } else { 1289 /* Generate random, not broadcast, locally administered BSSID. Mix in 1290 * own MAC address to make sure that devices that do not have proper 1291 * random number generator get different BSSID. */ 1292 get_random_bytes(bssid, ETH_ALEN); 1293 for (i = 0; i < ETH_ALEN; i++) 1294 bssid[i] ^= sdata->vif.addr[i]; 1295 bssid[0] &= ~0x01; 1296 bssid[0] |= 0x02; 1297 } 1298 1299 sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid); 1300 1301 capability = WLAN_CAPABILITY_IBSS; 1302 1303 if (ifibss->privacy) 1304 capability |= WLAN_CAPABILITY_PRIVACY; 1305 else 1306 sdata->drop_unencrypted = 0; 1307 1308 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int, 1309 &ifibss->chandef, ifibss->basic_rates, 1310 capability, 0, true); 1311 } 1312 1313 /* 1314 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH 1315 */ 1316 1317 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata) 1318 { 1319 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1320 struct ieee80211_local *local = sdata->local; 1321 struct cfg80211_bss *cbss; 1322 struct ieee80211_channel *chan = NULL; 1323 const u8 *bssid = NULL; 1324 enum nl80211_bss_scan_width scan_width; 1325 int active_ibss; 1326 u16 capability; 1327 1328 sdata_assert_lock(sdata); 1329 1330 active_ibss = ieee80211_sta_active_ibss(sdata); 1331 ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss); 1332 1333 if (active_ibss) 1334 return; 1335 1336 capability = WLAN_CAPABILITY_IBSS; 1337 if (ifibss->privacy) 1338 capability |= WLAN_CAPABILITY_PRIVACY; 1339 if (ifibss->fixed_bssid) 1340 bssid = ifibss->bssid; 1341 if (ifibss->fixed_channel) 1342 chan = ifibss->chandef.chan; 1343 if (!is_zero_ether_addr(ifibss->bssid)) 1344 bssid = ifibss->bssid; 1345 cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid, 1346 ifibss->ssid, ifibss->ssid_len, 1347 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY, 1348 capability); 1349 1350 if (cbss) { 1351 struct ieee80211_bss *bss; 1352 1353 bss = (void *)cbss->priv; 1354 ibss_dbg(sdata, 1355 "sta_find_ibss: selected %pM current %pM\n", 1356 cbss->bssid, ifibss->bssid); 1357 sdata_info(sdata, 1358 "Selected IBSS BSSID %pM based on configured SSID\n", 1359 cbss->bssid); 1360 1361 ieee80211_sta_join_ibss(sdata, bss); 1362 ieee80211_rx_bss_put(local, bss); 1363 return; 1364 } 1365 1366 /* if a fixed bssid and a fixed freq have been provided create the IBSS 1367 * directly and do not waste time scanning 1368 */ 1369 if (ifibss->fixed_bssid && ifibss->fixed_channel) { 1370 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n", 1371 bssid); 1372 ieee80211_sta_create_ibss(sdata); 1373 return; 1374 } 1375 1376 1377 ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n"); 1378 1379 /* Selected IBSS not found in current scan results - try to scan */ 1380 if (time_after(jiffies, ifibss->last_scan_completed + 1381 IEEE80211_SCAN_INTERVAL)) { 1382 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n"); 1383 1384 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef); 1385 ieee80211_request_ibss_scan(sdata, ifibss->ssid, 1386 ifibss->ssid_len, chan, 1387 scan_width); 1388 } else { 1389 int interval = IEEE80211_SCAN_INTERVAL; 1390 1391 if (time_after(jiffies, ifibss->ibss_join_req + 1392 IEEE80211_IBSS_JOIN_TIMEOUT)) 1393 ieee80211_sta_create_ibss(sdata); 1394 1395 mod_timer(&ifibss->timer, 1396 round_jiffies(jiffies + interval)); 1397 } 1398 } 1399 1400 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata, 1401 struct sk_buff *req) 1402 { 1403 struct ieee80211_mgmt *mgmt = (void *)req->data; 1404 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1405 struct ieee80211_local *local = sdata->local; 1406 int tx_last_beacon, len = req->len; 1407 struct sk_buff *skb; 1408 struct beacon_data *presp; 1409 u8 *pos, *end; 1410 1411 sdata_assert_lock(sdata); 1412 1413 presp = rcu_dereference_protected(ifibss->presp, 1414 lockdep_is_held(&sdata->wdev.mtx)); 1415 1416 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED || 1417 len < 24 + 2 || !presp) 1418 return; 1419 1420 tx_last_beacon = drv_tx_last_beacon(local); 1421 1422 ibss_dbg(sdata, 1423 "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n", 1424 mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon); 1425 1426 if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da)) 1427 return; 1428 1429 if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) && 1430 !is_broadcast_ether_addr(mgmt->bssid)) 1431 return; 1432 1433 end = ((u8 *) mgmt) + len; 1434 pos = mgmt->u.probe_req.variable; 1435 if (pos[0] != WLAN_EID_SSID || 1436 pos + 2 + pos[1] > end) { 1437 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n", 1438 mgmt->sa); 1439 return; 1440 } 1441 if (pos[1] != 0 && 1442 (pos[1] != ifibss->ssid_len || 1443 memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) { 1444 /* Ignore ProbeReq for foreign SSID */ 1445 return; 1446 } 1447 1448 /* Reply with ProbeResp */ 1449 skb = dev_alloc_skb(local->tx_headroom + presp->head_len); 1450 if (!skb) 1451 return; 1452 1453 skb_reserve(skb, local->tx_headroom); 1454 memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len); 1455 1456 memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN); 1457 ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa); 1458 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 1459 1460 /* avoid excessive retries for probe request to wildcard SSIDs */ 1461 if (pos[1] == 0) 1462 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK; 1463 1464 ieee80211_tx_skb(sdata, skb); 1465 } 1466 1467 static 1468 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata, 1469 struct ieee80211_mgmt *mgmt, size_t len, 1470 struct ieee80211_rx_status *rx_status) 1471 { 1472 size_t baselen; 1473 struct ieee802_11_elems elems; 1474 1475 BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) != 1476 offsetof(typeof(mgmt->u.beacon), variable)); 1477 1478 /* 1479 * either beacon or probe_resp but the variable field is at the 1480 * same offset 1481 */ 1482 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt; 1483 if (baselen > len) 1484 return; 1485 1486 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen, 1487 false, &elems); 1488 1489 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems); 1490 } 1491 1492 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata, 1493 struct sk_buff *skb) 1494 { 1495 struct ieee80211_rx_status *rx_status; 1496 struct ieee80211_mgmt *mgmt; 1497 u16 fc; 1498 struct ieee802_11_elems elems; 1499 int ies_len; 1500 1501 rx_status = IEEE80211_SKB_RXCB(skb); 1502 mgmt = (struct ieee80211_mgmt *) skb->data; 1503 fc = le16_to_cpu(mgmt->frame_control); 1504 1505 sdata_lock(sdata); 1506 1507 if (!sdata->u.ibss.ssid_len) 1508 goto mgmt_out; /* not ready to merge yet */ 1509 1510 switch (fc & IEEE80211_FCTL_STYPE) { 1511 case IEEE80211_STYPE_PROBE_REQ: 1512 ieee80211_rx_mgmt_probe_req(sdata, skb); 1513 break; 1514 case IEEE80211_STYPE_PROBE_RESP: 1515 case IEEE80211_STYPE_BEACON: 1516 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len, 1517 rx_status); 1518 break; 1519 case IEEE80211_STYPE_AUTH: 1520 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len); 1521 break; 1522 case IEEE80211_STYPE_DEAUTH: 1523 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len); 1524 break; 1525 case IEEE80211_STYPE_ACTION: 1526 switch (mgmt->u.action.category) { 1527 case WLAN_CATEGORY_SPECTRUM_MGMT: 1528 ies_len = skb->len - 1529 offsetof(struct ieee80211_mgmt, 1530 u.action.u.chan_switch.variable); 1531 1532 if (ies_len < 0) 1533 break; 1534 1535 ieee802_11_parse_elems( 1536 mgmt->u.action.u.chan_switch.variable, 1537 ies_len, true, &elems); 1538 1539 if (elems.parse_error) 1540 break; 1541 1542 ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len, 1543 rx_status, &elems); 1544 break; 1545 } 1546 } 1547 1548 mgmt_out: 1549 sdata_unlock(sdata); 1550 } 1551 1552 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata) 1553 { 1554 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1555 struct sta_info *sta; 1556 1557 sdata_lock(sdata); 1558 1559 /* 1560 * Work could be scheduled after scan or similar 1561 * when we aren't even joined (or trying) with a 1562 * network. 1563 */ 1564 if (!ifibss->ssid_len) 1565 goto out; 1566 1567 spin_lock_bh(&ifibss->incomplete_lock); 1568 while (!list_empty(&ifibss->incomplete_stations)) { 1569 sta = list_first_entry(&ifibss->incomplete_stations, 1570 struct sta_info, list); 1571 list_del(&sta->list); 1572 spin_unlock_bh(&ifibss->incomplete_lock); 1573 1574 ieee80211_ibss_finish_sta(sta); 1575 rcu_read_unlock(); 1576 spin_lock_bh(&ifibss->incomplete_lock); 1577 } 1578 spin_unlock_bh(&ifibss->incomplete_lock); 1579 1580 switch (ifibss->state) { 1581 case IEEE80211_IBSS_MLME_SEARCH: 1582 ieee80211_sta_find_ibss(sdata); 1583 break; 1584 case IEEE80211_IBSS_MLME_JOINED: 1585 ieee80211_sta_merge_ibss(sdata); 1586 break; 1587 default: 1588 WARN_ON(1); 1589 break; 1590 } 1591 1592 out: 1593 sdata_unlock(sdata); 1594 } 1595 1596 static void ieee80211_ibss_timer(unsigned long data) 1597 { 1598 struct ieee80211_sub_if_data *sdata = 1599 (struct ieee80211_sub_if_data *) data; 1600 1601 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 1602 } 1603 1604 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata) 1605 { 1606 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1607 1608 setup_timer(&ifibss->timer, ieee80211_ibss_timer, 1609 (unsigned long) sdata); 1610 INIT_LIST_HEAD(&ifibss->incomplete_stations); 1611 spin_lock_init(&ifibss->incomplete_lock); 1612 INIT_WORK(&ifibss->csa_connection_drop_work, 1613 ieee80211_csa_connection_drop_work); 1614 } 1615 1616 /* scan finished notification */ 1617 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local) 1618 { 1619 struct ieee80211_sub_if_data *sdata; 1620 1621 mutex_lock(&local->iflist_mtx); 1622 list_for_each_entry(sdata, &local->interfaces, list) { 1623 if (!ieee80211_sdata_running(sdata)) 1624 continue; 1625 if (sdata->vif.type != NL80211_IFTYPE_ADHOC) 1626 continue; 1627 sdata->u.ibss.last_scan_completed = jiffies; 1628 ieee80211_queue_work(&local->hw, &sdata->work); 1629 } 1630 mutex_unlock(&local->iflist_mtx); 1631 } 1632 1633 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata, 1634 struct cfg80211_ibss_params *params) 1635 { 1636 u32 changed = 0; 1637 u32 rate_flags; 1638 struct ieee80211_supported_band *sband; 1639 int i; 1640 1641 if (params->bssid) { 1642 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN); 1643 sdata->u.ibss.fixed_bssid = true; 1644 } else 1645 sdata->u.ibss.fixed_bssid = false; 1646 1647 sdata->u.ibss.privacy = params->privacy; 1648 sdata->u.ibss.control_port = params->control_port; 1649 sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs; 1650 sdata->u.ibss.basic_rates = params->basic_rates; 1651 1652 /* fix basic_rates if channel does not support these rates */ 1653 rate_flags = ieee80211_chandef_rate_flags(¶ms->chandef); 1654 sband = sdata->local->hw.wiphy->bands[params->chandef.chan->band]; 1655 for (i = 0; i < sband->n_bitrates; i++) { 1656 if ((rate_flags & sband->bitrates[i].flags) != rate_flags) 1657 sdata->u.ibss.basic_rates &= ~BIT(i); 1658 } 1659 memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate, 1660 sizeof(params->mcast_rate)); 1661 1662 sdata->vif.bss_conf.beacon_int = params->beacon_interval; 1663 1664 sdata->u.ibss.chandef = params->chandef; 1665 sdata->u.ibss.fixed_channel = params->channel_fixed; 1666 1667 if (params->ie) { 1668 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len, 1669 GFP_KERNEL); 1670 if (sdata->u.ibss.ie) 1671 sdata->u.ibss.ie_len = params->ie_len; 1672 } 1673 1674 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; 1675 sdata->u.ibss.ibss_join_req = jiffies; 1676 1677 memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len); 1678 sdata->u.ibss.ssid_len = params->ssid_len; 1679 1680 memcpy(&sdata->u.ibss.ht_capa, ¶ms->ht_capa, 1681 sizeof(sdata->u.ibss.ht_capa)); 1682 memcpy(&sdata->u.ibss.ht_capa_mask, ¶ms->ht_capa_mask, 1683 sizeof(sdata->u.ibss.ht_capa_mask)); 1684 1685 /* 1686 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is 1687 * reserved, but an HT STA shall protect HT transmissions as though 1688 * the HT Protection field were set to non-HT mixed mode. 1689 * 1690 * In an IBSS, the RIFS Mode field of the HT Operation element is 1691 * also reserved, but an HT STA shall operate as though this field 1692 * were set to 1. 1693 */ 1694 1695 sdata->vif.bss_conf.ht_operation_mode |= 1696 IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED 1697 | IEEE80211_HT_PARAM_RIFS_MODE; 1698 1699 changed |= BSS_CHANGED_HT; 1700 ieee80211_bss_info_change_notify(sdata, changed); 1701 1702 sdata->smps_mode = IEEE80211_SMPS_OFF; 1703 sdata->needed_rx_chains = sdata->local->rx_chains; 1704 1705 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 1706 1707 return 0; 1708 } 1709 1710 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata) 1711 { 1712 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1713 1714 ieee80211_ibss_disconnect(sdata); 1715 ifibss->ssid_len = 0; 1716 memset(ifibss->bssid, 0, ETH_ALEN); 1717 1718 /* remove beacon */ 1719 kfree(sdata->u.ibss.ie); 1720 1721 /* on the next join, re-program HT parameters */ 1722 memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa)); 1723 memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask)); 1724 1725 synchronize_rcu(); 1726 1727 skb_queue_purge(&sdata->skb_queue); 1728 1729 del_timer_sync(&sdata->u.ibss.timer); 1730 1731 return 0; 1732 } 1733