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 * Copyright 2013-2014 Intel Mobile Communications GmbH 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of the GNU General Public License version 2 as 13 * published by the Free Software Foundation. 14 */ 15 16 #include <linux/delay.h> 17 #include <linux/slab.h> 18 #include <linux/if_ether.h> 19 #include <linux/skbuff.h> 20 #include <linux/if_arp.h> 21 #include <linux/etherdevice.h> 22 #include <linux/rtnetlink.h> 23 #include <net/mac80211.h> 24 25 #include "ieee80211_i.h" 26 #include "driver-ops.h" 27 #include "rate.h" 28 29 #define IEEE80211_SCAN_INTERVAL (2 * HZ) 30 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ) 31 32 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ) 33 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ) 34 #define IEEE80211_IBSS_RSN_INACTIVITY_LIMIT (10 * HZ) 35 36 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128 37 38 static struct beacon_data * 39 ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata, 40 const int beacon_int, const u32 basic_rates, 41 const u16 capability, u64 tsf, 42 struct cfg80211_chan_def *chandef, 43 bool *have_higher_than_11mbit, 44 struct cfg80211_csa_settings *csa_settings) 45 { 46 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 47 struct ieee80211_local *local = sdata->local; 48 int rates_n = 0, i, ri; 49 struct ieee80211_mgmt *mgmt; 50 u8 *pos; 51 struct ieee80211_supported_band *sband; 52 u32 rate_flags, rates = 0, rates_added = 0; 53 struct beacon_data *presp; 54 int frame_len; 55 int shift; 56 57 /* Build IBSS probe response */ 58 frame_len = sizeof(struct ieee80211_hdr_3addr) + 59 12 /* struct ieee80211_mgmt.u.beacon */ + 60 2 + IEEE80211_MAX_SSID_LEN /* max SSID */ + 61 2 + 8 /* max Supported Rates */ + 62 3 /* max DS params */ + 63 4 /* IBSS params */ + 64 5 /* Channel Switch Announcement */ + 65 2 + (IEEE80211_MAX_SUPP_RATES - 8) + 66 2 + sizeof(struct ieee80211_ht_cap) + 67 2 + sizeof(struct ieee80211_ht_operation) + 68 ifibss->ie_len; 69 presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL); 70 if (!presp) 71 return NULL; 72 73 presp->head = (void *)(presp + 1); 74 75 mgmt = (void *) presp->head; 76 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 77 IEEE80211_STYPE_PROBE_RESP); 78 eth_broadcast_addr(mgmt->da); 79 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 80 memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN); 81 mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int); 82 mgmt->u.beacon.timestamp = cpu_to_le64(tsf); 83 mgmt->u.beacon.capab_info = cpu_to_le16(capability); 84 85 pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable); 86 87 *pos++ = WLAN_EID_SSID; 88 *pos++ = ifibss->ssid_len; 89 memcpy(pos, ifibss->ssid, ifibss->ssid_len); 90 pos += ifibss->ssid_len; 91 92 sband = local->hw.wiphy->bands[chandef->chan->band]; 93 rate_flags = ieee80211_chandef_rate_flags(chandef); 94 shift = ieee80211_chandef_get_shift(chandef); 95 rates_n = 0; 96 if (have_higher_than_11mbit) 97 *have_higher_than_11mbit = false; 98 99 for (i = 0; i < sband->n_bitrates; i++) { 100 if ((rate_flags & sband->bitrates[i].flags) != rate_flags) 101 continue; 102 if (sband->bitrates[i].bitrate > 110 && 103 have_higher_than_11mbit) 104 *have_higher_than_11mbit = true; 105 106 rates |= BIT(i); 107 rates_n++; 108 } 109 110 *pos++ = WLAN_EID_SUPP_RATES; 111 *pos++ = min_t(int, 8, rates_n); 112 for (ri = 0; ri < sband->n_bitrates; ri++) { 113 int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate, 114 5 * (1 << shift)); 115 u8 basic = 0; 116 if (!(rates & BIT(ri))) 117 continue; 118 119 if (basic_rates & BIT(ri)) 120 basic = 0x80; 121 *pos++ = basic | (u8) rate; 122 if (++rates_added == 8) { 123 ri++; /* continue at next rate for EXT_SUPP_RATES */ 124 break; 125 } 126 } 127 128 if (sband->band == IEEE80211_BAND_2GHZ) { 129 *pos++ = WLAN_EID_DS_PARAMS; 130 *pos++ = 1; 131 *pos++ = ieee80211_frequency_to_channel( 132 chandef->chan->center_freq); 133 } 134 135 *pos++ = WLAN_EID_IBSS_PARAMS; 136 *pos++ = 2; 137 /* FIX: set ATIM window based on scan results */ 138 *pos++ = 0; 139 *pos++ = 0; 140 141 if (csa_settings) { 142 *pos++ = WLAN_EID_CHANNEL_SWITCH; 143 *pos++ = 3; 144 *pos++ = csa_settings->block_tx ? 1 : 0; 145 *pos++ = ieee80211_frequency_to_channel( 146 csa_settings->chandef.chan->center_freq); 147 presp->csa_counter_offsets[0] = (pos - presp->head); 148 *pos++ = csa_settings->count; 149 } 150 151 /* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */ 152 if (rates_n > 8) { 153 *pos++ = WLAN_EID_EXT_SUPP_RATES; 154 *pos++ = rates_n - 8; 155 for (; ri < sband->n_bitrates; ri++) { 156 int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate, 157 5 * (1 << shift)); 158 u8 basic = 0; 159 if (!(rates & BIT(ri))) 160 continue; 161 162 if (basic_rates & BIT(ri)) 163 basic = 0x80; 164 *pos++ = basic | (u8) rate; 165 } 166 } 167 168 if (ifibss->ie_len) { 169 memcpy(pos, ifibss->ie, ifibss->ie_len); 170 pos += ifibss->ie_len; 171 } 172 173 /* add HT capability and information IEs */ 174 if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT && 175 chandef->width != NL80211_CHAN_WIDTH_5 && 176 chandef->width != NL80211_CHAN_WIDTH_10 && 177 sband->ht_cap.ht_supported) { 178 struct ieee80211_sta_ht_cap ht_cap; 179 180 memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap)); 181 ieee80211_apply_htcap_overrides(sdata, &ht_cap); 182 183 pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap); 184 /* 185 * Note: According to 802.11n-2009 9.13.3.1, HT Protection 186 * field and RIFS Mode are reserved in IBSS mode, therefore 187 * keep them at 0 188 */ 189 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap, 190 chandef, 0); 191 } 192 193 if (local->hw.queues >= IEEE80211_NUM_ACS) 194 pos = ieee80211_add_wmm_info_ie(pos, 0); /* U-APSD not in use */ 195 196 presp->head_len = pos - presp->head; 197 if (WARN_ON(presp->head_len > frame_len)) 198 goto error; 199 200 return presp; 201 error: 202 kfree(presp); 203 return NULL; 204 } 205 206 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 207 const u8 *bssid, const int beacon_int, 208 struct cfg80211_chan_def *req_chandef, 209 const u32 basic_rates, 210 const u16 capability, u64 tsf, 211 bool creator) 212 { 213 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 214 struct ieee80211_local *local = sdata->local; 215 struct ieee80211_mgmt *mgmt; 216 struct cfg80211_bss *bss; 217 u32 bss_change; 218 struct cfg80211_chan_def chandef; 219 struct ieee80211_channel *chan; 220 struct beacon_data *presp; 221 enum nl80211_bss_scan_width scan_width; 222 bool have_higher_than_11mbit; 223 bool radar_required; 224 int err; 225 226 sdata_assert_lock(sdata); 227 228 /* Reset own TSF to allow time synchronization work. */ 229 drv_reset_tsf(local, sdata); 230 231 if (!ether_addr_equal(ifibss->bssid, bssid)) 232 sta_info_flush(sdata); 233 234 /* if merging, indicate to driver that we leave the old IBSS */ 235 if (sdata->vif.bss_conf.ibss_joined) { 236 sdata->vif.bss_conf.ibss_joined = false; 237 sdata->vif.bss_conf.ibss_creator = false; 238 sdata->vif.bss_conf.enable_beacon = false; 239 netif_carrier_off(sdata->dev); 240 ieee80211_bss_info_change_notify(sdata, 241 BSS_CHANGED_IBSS | 242 BSS_CHANGED_BEACON_ENABLED); 243 drv_leave_ibss(local, sdata); 244 } 245 246 presp = rcu_dereference_protected(ifibss->presp, 247 lockdep_is_held(&sdata->wdev.mtx)); 248 RCU_INIT_POINTER(ifibss->presp, NULL); 249 if (presp) 250 kfree_rcu(presp, rcu_head); 251 252 sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0; 253 254 /* make a copy of the chandef, it could be modified below. */ 255 chandef = *req_chandef; 256 chan = chandef.chan; 257 if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef, 258 NL80211_IFTYPE_ADHOC)) { 259 if (chandef.width == NL80211_CHAN_WIDTH_5 || 260 chandef.width == NL80211_CHAN_WIDTH_10 || 261 chandef.width == NL80211_CHAN_WIDTH_20_NOHT || 262 chandef.width == NL80211_CHAN_WIDTH_20) { 263 sdata_info(sdata, 264 "Failed to join IBSS, beacons forbidden\n"); 265 return; 266 } 267 chandef.width = NL80211_CHAN_WIDTH_20; 268 chandef.center_freq1 = chan->center_freq; 269 /* check again for downgraded chandef */ 270 if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef, 271 NL80211_IFTYPE_ADHOC)) { 272 sdata_info(sdata, 273 "Failed to join IBSS, beacons forbidden\n"); 274 return; 275 } 276 } 277 278 err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy, 279 &chandef, NL80211_IFTYPE_ADHOC); 280 if (err < 0) { 281 sdata_info(sdata, 282 "Failed to join IBSS, invalid chandef\n"); 283 return; 284 } 285 if (err > 0 && !ifibss->userspace_handles_dfs) { 286 sdata_info(sdata, 287 "Failed to join IBSS, DFS channel without control program\n"); 288 return; 289 } 290 291 radar_required = err; 292 293 mutex_lock(&local->mtx); 294 if (ieee80211_vif_use_channel(sdata, &chandef, 295 ifibss->fixed_channel ? 296 IEEE80211_CHANCTX_SHARED : 297 IEEE80211_CHANCTX_EXCLUSIVE)) { 298 sdata_info(sdata, "Failed to join IBSS, no channel context\n"); 299 mutex_unlock(&local->mtx); 300 return; 301 } 302 sdata->radar_required = radar_required; 303 mutex_unlock(&local->mtx); 304 305 memcpy(ifibss->bssid, bssid, ETH_ALEN); 306 307 presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates, 308 capability, tsf, &chandef, 309 &have_higher_than_11mbit, NULL); 310 if (!presp) 311 return; 312 313 rcu_assign_pointer(ifibss->presp, presp); 314 mgmt = (void *)presp->head; 315 316 sdata->vif.bss_conf.enable_beacon = true; 317 sdata->vif.bss_conf.beacon_int = beacon_int; 318 sdata->vif.bss_conf.basic_rates = basic_rates; 319 sdata->vif.bss_conf.ssid_len = ifibss->ssid_len; 320 memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len); 321 bss_change = BSS_CHANGED_BEACON_INT; 322 bss_change |= ieee80211_reset_erp_info(sdata); 323 bss_change |= BSS_CHANGED_BSSID; 324 bss_change |= BSS_CHANGED_BEACON; 325 bss_change |= BSS_CHANGED_BEACON_ENABLED; 326 bss_change |= BSS_CHANGED_BASIC_RATES; 327 bss_change |= BSS_CHANGED_HT; 328 bss_change |= BSS_CHANGED_IBSS; 329 bss_change |= BSS_CHANGED_SSID; 330 331 /* 332 * In 5 GHz/802.11a, we can always use short slot time. 333 * (IEEE 802.11-2012 18.3.8.7) 334 * 335 * In 2.4GHz, we must always use long slots in IBSS for compatibility 336 * reasons. 337 * (IEEE 802.11-2012 19.4.5) 338 * 339 * HT follows these specifications (IEEE 802.11-2012 20.3.18) 340 */ 341 sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ; 342 bss_change |= BSS_CHANGED_ERP_SLOT; 343 344 /* cf. IEEE 802.11 9.2.12 */ 345 if (chan->band == IEEE80211_BAND_2GHZ && have_higher_than_11mbit) 346 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE; 347 else 348 sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE; 349 350 ieee80211_set_wmm_default(sdata, true); 351 352 sdata->vif.bss_conf.ibss_joined = true; 353 sdata->vif.bss_conf.ibss_creator = creator; 354 355 err = drv_join_ibss(local, sdata); 356 if (err) { 357 sdata->vif.bss_conf.ibss_joined = false; 358 sdata->vif.bss_conf.ibss_creator = false; 359 sdata->vif.bss_conf.enable_beacon = false; 360 sdata->vif.bss_conf.ssid_len = 0; 361 RCU_INIT_POINTER(ifibss->presp, NULL); 362 kfree_rcu(presp, rcu_head); 363 mutex_lock(&local->mtx); 364 ieee80211_vif_release_channel(sdata); 365 mutex_unlock(&local->mtx); 366 sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n", 367 err); 368 return; 369 } 370 371 ieee80211_bss_info_change_notify(sdata, bss_change); 372 373 ifibss->state = IEEE80211_IBSS_MLME_JOINED; 374 mod_timer(&ifibss->timer, 375 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 376 377 scan_width = cfg80211_chandef_to_scan_width(&chandef); 378 bss = cfg80211_inform_bss_width_frame(local->hw.wiphy, chan, 379 scan_width, mgmt, 380 presp->head_len, 0, GFP_KERNEL); 381 cfg80211_put_bss(local->hw.wiphy, bss); 382 netif_carrier_on(sdata->dev); 383 cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL); 384 } 385 386 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 387 struct ieee80211_bss *bss) 388 { 389 struct cfg80211_bss *cbss = 390 container_of((void *)bss, struct cfg80211_bss, priv); 391 struct ieee80211_supported_band *sband; 392 struct cfg80211_chan_def chandef; 393 u32 basic_rates; 394 int i, j; 395 u16 beacon_int = cbss->beacon_interval; 396 const struct cfg80211_bss_ies *ies; 397 enum nl80211_channel_type chan_type; 398 u64 tsf; 399 u32 rate_flags; 400 int shift; 401 402 sdata_assert_lock(sdata); 403 404 if (beacon_int < 10) 405 beacon_int = 10; 406 407 switch (sdata->u.ibss.chandef.width) { 408 case NL80211_CHAN_WIDTH_20_NOHT: 409 case NL80211_CHAN_WIDTH_20: 410 case NL80211_CHAN_WIDTH_40: 411 chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef); 412 cfg80211_chandef_create(&chandef, cbss->channel, chan_type); 413 break; 414 case NL80211_CHAN_WIDTH_5: 415 case NL80211_CHAN_WIDTH_10: 416 cfg80211_chandef_create(&chandef, cbss->channel, 417 NL80211_CHAN_WIDTH_20_NOHT); 418 chandef.width = sdata->u.ibss.chandef.width; 419 break; 420 default: 421 /* fall back to 20 MHz for unsupported modes */ 422 cfg80211_chandef_create(&chandef, cbss->channel, 423 NL80211_CHAN_WIDTH_20_NOHT); 424 break; 425 } 426 427 sband = sdata->local->hw.wiphy->bands[cbss->channel->band]; 428 rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef); 429 shift = ieee80211_vif_get_shift(&sdata->vif); 430 431 basic_rates = 0; 432 433 for (i = 0; i < bss->supp_rates_len; i++) { 434 int rate = bss->supp_rates[i] & 0x7f; 435 bool is_basic = !!(bss->supp_rates[i] & 0x80); 436 437 for (j = 0; j < sband->n_bitrates; j++) { 438 int brate; 439 if ((rate_flags & sband->bitrates[j].flags) 440 != rate_flags) 441 continue; 442 443 brate = DIV_ROUND_UP(sband->bitrates[j].bitrate, 444 5 * (1 << shift)); 445 if (brate == rate) { 446 if (is_basic) 447 basic_rates |= BIT(j); 448 break; 449 } 450 } 451 } 452 453 rcu_read_lock(); 454 ies = rcu_dereference(cbss->ies); 455 tsf = ies->tsf; 456 rcu_read_unlock(); 457 458 __ieee80211_sta_join_ibss(sdata, cbss->bssid, 459 beacon_int, 460 &chandef, 461 basic_rates, 462 cbss->capability, 463 tsf, false); 464 } 465 466 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata, 467 struct cfg80211_csa_settings *csa_settings) 468 { 469 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 470 struct beacon_data *presp, *old_presp; 471 struct cfg80211_bss *cbss; 472 const struct cfg80211_bss_ies *ies; 473 u16 capability; 474 u64 tsf; 475 int ret = 0; 476 477 sdata_assert_lock(sdata); 478 479 capability = WLAN_CAPABILITY_IBSS; 480 481 if (ifibss->privacy) 482 capability |= WLAN_CAPABILITY_PRIVACY; 483 484 cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan, 485 ifibss->bssid, ifibss->ssid, 486 ifibss->ssid_len, WLAN_CAPABILITY_IBSS | 487 WLAN_CAPABILITY_PRIVACY, 488 capability); 489 490 if (WARN_ON(!cbss)) { 491 ret = -EINVAL; 492 goto out; 493 } 494 495 rcu_read_lock(); 496 ies = rcu_dereference(cbss->ies); 497 tsf = ies->tsf; 498 rcu_read_unlock(); 499 cfg80211_put_bss(sdata->local->hw.wiphy, cbss); 500 501 old_presp = rcu_dereference_protected(ifibss->presp, 502 lockdep_is_held(&sdata->wdev.mtx)); 503 504 presp = ieee80211_ibss_build_presp(sdata, 505 sdata->vif.bss_conf.beacon_int, 506 sdata->vif.bss_conf.basic_rates, 507 capability, tsf, &ifibss->chandef, 508 NULL, csa_settings); 509 if (!presp) { 510 ret = -ENOMEM; 511 goto out; 512 } 513 514 rcu_assign_pointer(ifibss->presp, presp); 515 if (old_presp) 516 kfree_rcu(old_presp, rcu_head); 517 518 return BSS_CHANGED_BEACON; 519 out: 520 return ret; 521 } 522 523 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata) 524 { 525 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 526 struct cfg80211_bss *cbss; 527 int err, changed = 0; 528 u16 capability; 529 530 sdata_assert_lock(sdata); 531 532 /* update cfg80211 bss information with the new channel */ 533 if (!is_zero_ether_addr(ifibss->bssid)) { 534 capability = WLAN_CAPABILITY_IBSS; 535 536 if (ifibss->privacy) 537 capability |= WLAN_CAPABILITY_PRIVACY; 538 539 cbss = cfg80211_get_bss(sdata->local->hw.wiphy, 540 ifibss->chandef.chan, 541 ifibss->bssid, ifibss->ssid, 542 ifibss->ssid_len, WLAN_CAPABILITY_IBSS | 543 WLAN_CAPABILITY_PRIVACY, 544 capability); 545 /* XXX: should not really modify cfg80211 data */ 546 if (cbss) { 547 cbss->channel = sdata->csa_chandef.chan; 548 cfg80211_put_bss(sdata->local->hw.wiphy, cbss); 549 } 550 } 551 552 ifibss->chandef = sdata->csa_chandef; 553 554 /* generate the beacon */ 555 err = ieee80211_ibss_csa_beacon(sdata, NULL); 556 if (err < 0) 557 return err; 558 559 changed |= err; 560 561 return changed; 562 } 563 564 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata) 565 { 566 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 567 568 cancel_work_sync(&ifibss->csa_connection_drop_work); 569 } 570 571 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta) 572 __acquires(RCU) 573 { 574 struct ieee80211_sub_if_data *sdata = sta->sdata; 575 u8 addr[ETH_ALEN]; 576 577 memcpy(addr, sta->sta.addr, ETH_ALEN); 578 579 ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr); 580 581 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH); 582 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC); 583 /* authorize the station only if the network is not RSN protected. If 584 * not wait for the userspace to authorize it */ 585 if (!sta->sdata->u.ibss.control_port) 586 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED); 587 588 rate_control_rate_init(sta); 589 590 /* If it fails, maybe we raced another insertion? */ 591 if (sta_info_insert_rcu(sta)) 592 return sta_info_get(sdata, addr); 593 return sta; 594 } 595 596 static struct sta_info * 597 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid, 598 const u8 *addr, u32 supp_rates) 599 __acquires(RCU) 600 { 601 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 602 struct ieee80211_local *local = sdata->local; 603 struct sta_info *sta; 604 struct ieee80211_chanctx_conf *chanctx_conf; 605 struct ieee80211_supported_band *sband; 606 enum nl80211_bss_scan_width scan_width; 607 int band; 608 609 /* 610 * XXX: Consider removing the least recently used entry and 611 * allow new one to be added. 612 */ 613 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 614 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n", 615 sdata->name, addr); 616 rcu_read_lock(); 617 return NULL; 618 } 619 620 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) { 621 rcu_read_lock(); 622 return NULL; 623 } 624 625 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) { 626 rcu_read_lock(); 627 return NULL; 628 } 629 630 rcu_read_lock(); 631 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); 632 if (WARN_ON_ONCE(!chanctx_conf)) 633 return NULL; 634 band = chanctx_conf->def.chan->band; 635 scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def); 636 rcu_read_unlock(); 637 638 sta = sta_info_alloc(sdata, addr, GFP_KERNEL); 639 if (!sta) { 640 rcu_read_lock(); 641 return NULL; 642 } 643 644 sta->last_rx = jiffies; 645 646 /* make sure mandatory rates are always added */ 647 sband = local->hw.wiphy->bands[band]; 648 sta->sta.supp_rates[band] = supp_rates | 649 ieee80211_mandatory_rates(sband, scan_width); 650 651 return ieee80211_ibss_finish_sta(sta); 652 } 653 654 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata) 655 { 656 struct ieee80211_local *local = sdata->local; 657 int active = 0; 658 struct sta_info *sta; 659 660 sdata_assert_lock(sdata); 661 662 rcu_read_lock(); 663 664 list_for_each_entry_rcu(sta, &local->sta_list, list) { 665 if (sta->sdata == sdata && 666 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL, 667 jiffies)) { 668 active++; 669 break; 670 } 671 } 672 673 rcu_read_unlock(); 674 675 return active; 676 } 677 678 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata) 679 { 680 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 681 struct ieee80211_local *local = sdata->local; 682 struct cfg80211_bss *cbss; 683 struct beacon_data *presp; 684 struct sta_info *sta; 685 u16 capability; 686 687 if (!is_zero_ether_addr(ifibss->bssid)) { 688 capability = WLAN_CAPABILITY_IBSS; 689 690 if (ifibss->privacy) 691 capability |= WLAN_CAPABILITY_PRIVACY; 692 693 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan, 694 ifibss->bssid, ifibss->ssid, 695 ifibss->ssid_len, WLAN_CAPABILITY_IBSS | 696 WLAN_CAPABILITY_PRIVACY, 697 capability); 698 699 if (cbss) { 700 cfg80211_unlink_bss(local->hw.wiphy, cbss); 701 cfg80211_put_bss(sdata->local->hw.wiphy, cbss); 702 } 703 } 704 705 ifibss->state = IEEE80211_IBSS_MLME_SEARCH; 706 707 sta_info_flush(sdata); 708 709 spin_lock_bh(&ifibss->incomplete_lock); 710 while (!list_empty(&ifibss->incomplete_stations)) { 711 sta = list_first_entry(&ifibss->incomplete_stations, 712 struct sta_info, list); 713 list_del(&sta->list); 714 spin_unlock_bh(&ifibss->incomplete_lock); 715 716 sta_info_free(local, sta); 717 spin_lock_bh(&ifibss->incomplete_lock); 718 } 719 spin_unlock_bh(&ifibss->incomplete_lock); 720 721 netif_carrier_off(sdata->dev); 722 723 sdata->vif.bss_conf.ibss_joined = false; 724 sdata->vif.bss_conf.ibss_creator = false; 725 sdata->vif.bss_conf.enable_beacon = false; 726 sdata->vif.bss_conf.ssid_len = 0; 727 728 /* remove beacon */ 729 presp = rcu_dereference_protected(ifibss->presp, 730 lockdep_is_held(&sdata->wdev.mtx)); 731 RCU_INIT_POINTER(sdata->u.ibss.presp, NULL); 732 if (presp) 733 kfree_rcu(presp, rcu_head); 734 735 clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state); 736 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED | 737 BSS_CHANGED_IBSS); 738 drv_leave_ibss(local, sdata); 739 mutex_lock(&local->mtx); 740 ieee80211_vif_release_channel(sdata); 741 mutex_unlock(&local->mtx); 742 } 743 744 static void ieee80211_csa_connection_drop_work(struct work_struct *work) 745 { 746 struct ieee80211_sub_if_data *sdata = 747 container_of(work, struct ieee80211_sub_if_data, 748 u.ibss.csa_connection_drop_work); 749 750 sdata_lock(sdata); 751 752 ieee80211_ibss_disconnect(sdata); 753 synchronize_rcu(); 754 skb_queue_purge(&sdata->skb_queue); 755 756 /* trigger a scan to find another IBSS network to join */ 757 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 758 759 sdata_unlock(sdata); 760 } 761 762 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata) 763 { 764 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 765 int err; 766 767 /* if the current channel is a DFS channel, mark the channel as 768 * unavailable. 769 */ 770 err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy, 771 &ifibss->chandef, 772 NL80211_IFTYPE_ADHOC); 773 if (err > 0) 774 cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef, 775 GFP_ATOMIC); 776 } 777 778 static bool 779 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata, 780 struct ieee802_11_elems *elems, 781 bool beacon) 782 { 783 struct cfg80211_csa_settings params; 784 struct ieee80211_csa_ie csa_ie; 785 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 786 enum nl80211_channel_type ch_type; 787 int err; 788 u32 sta_flags; 789 790 sdata_assert_lock(sdata); 791 792 sta_flags = IEEE80211_STA_DISABLE_VHT; 793 switch (ifibss->chandef.width) { 794 case NL80211_CHAN_WIDTH_5: 795 case NL80211_CHAN_WIDTH_10: 796 case NL80211_CHAN_WIDTH_20_NOHT: 797 sta_flags |= IEEE80211_STA_DISABLE_HT; 798 /* fall through */ 799 case NL80211_CHAN_WIDTH_20: 800 sta_flags |= IEEE80211_STA_DISABLE_40MHZ; 801 break; 802 default: 803 break; 804 } 805 806 memset(¶ms, 0, sizeof(params)); 807 memset(&csa_ie, 0, sizeof(csa_ie)); 808 err = ieee80211_parse_ch_switch_ie(sdata, elems, 809 ifibss->chandef.chan->band, 810 sta_flags, ifibss->bssid, &csa_ie); 811 /* can't switch to destination channel, fail */ 812 if (err < 0) 813 goto disconnect; 814 815 /* did not contain a CSA */ 816 if (err) 817 return false; 818 819 /* channel switch is not supported, disconnect */ 820 if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH)) 821 goto disconnect; 822 823 params.count = csa_ie.count; 824 params.chandef = csa_ie.chandef; 825 826 switch (ifibss->chandef.width) { 827 case NL80211_CHAN_WIDTH_20_NOHT: 828 case NL80211_CHAN_WIDTH_20: 829 case NL80211_CHAN_WIDTH_40: 830 /* keep our current HT mode (HT20/HT40+/HT40-), even if 831 * another mode has been announced. The mode is not adopted 832 * within the beacon while doing CSA and we should therefore 833 * keep the mode which we announce. 834 */ 835 ch_type = cfg80211_get_chandef_type(&ifibss->chandef); 836 cfg80211_chandef_create(¶ms.chandef, params.chandef.chan, 837 ch_type); 838 break; 839 case NL80211_CHAN_WIDTH_5: 840 case NL80211_CHAN_WIDTH_10: 841 if (params.chandef.width != ifibss->chandef.width) { 842 sdata_info(sdata, 843 "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n", 844 ifibss->bssid, 845 params.chandef.chan->center_freq, 846 params.chandef.width, 847 params.chandef.center_freq1, 848 params.chandef.center_freq2); 849 goto disconnect; 850 } 851 break; 852 default: 853 /* should not happen, sta_flags should prevent VHT modes. */ 854 WARN_ON(1); 855 goto disconnect; 856 } 857 858 if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, ¶ms.chandef, 859 NL80211_IFTYPE_ADHOC)) { 860 sdata_info(sdata, 861 "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n", 862 ifibss->bssid, 863 params.chandef.chan->center_freq, 864 params.chandef.width, 865 params.chandef.center_freq1, 866 params.chandef.center_freq2); 867 goto disconnect; 868 } 869 870 err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy, 871 ¶ms.chandef, 872 NL80211_IFTYPE_ADHOC); 873 if (err < 0) 874 goto disconnect; 875 if (err > 0 && !ifibss->userspace_handles_dfs) { 876 /* IBSS-DFS only allowed with a control program */ 877 goto disconnect; 878 } 879 880 params.radar_required = err; 881 882 if (cfg80211_chandef_identical(¶ms.chandef, 883 &sdata->vif.bss_conf.chandef)) { 884 ibss_dbg(sdata, 885 "received csa with an identical chandef, ignoring\n"); 886 return true; 887 } 888 889 /* all checks done, now perform the channel switch. */ 890 ibss_dbg(sdata, 891 "received channel switch announcement to go to channel %d MHz\n", 892 params.chandef.chan->center_freq); 893 894 params.block_tx = !!csa_ie.mode; 895 896 if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev, 897 ¶ms)) 898 goto disconnect; 899 900 ieee80211_ibss_csa_mark_radar(sdata); 901 902 return true; 903 disconnect: 904 ibss_dbg(sdata, "Can't handle channel switch, disconnect\n"); 905 ieee80211_queue_work(&sdata->local->hw, 906 &ifibss->csa_connection_drop_work); 907 908 ieee80211_ibss_csa_mark_radar(sdata); 909 910 return true; 911 } 912 913 static void 914 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata, 915 struct ieee80211_mgmt *mgmt, size_t len, 916 struct ieee80211_rx_status *rx_status, 917 struct ieee802_11_elems *elems) 918 { 919 int required_len; 920 921 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 922 return; 923 924 /* CSA is the only action we handle for now */ 925 if (mgmt->u.action.u.measurement.action_code != 926 WLAN_ACTION_SPCT_CHL_SWITCH) 927 return; 928 929 required_len = IEEE80211_MIN_ACTION_SIZE + 930 sizeof(mgmt->u.action.u.chan_switch); 931 if (len < required_len) 932 return; 933 934 if (!sdata->vif.csa_active) 935 ieee80211_ibss_process_chanswitch(sdata, elems, false); 936 } 937 938 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata, 939 struct ieee80211_mgmt *mgmt, 940 size_t len) 941 { 942 u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code); 943 944 if (len < IEEE80211_DEAUTH_FRAME_LEN) 945 return; 946 947 ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n", 948 mgmt->sa, mgmt->da, mgmt->bssid, reason); 949 sta_info_destroy_addr(sdata, mgmt->sa); 950 } 951 952 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata, 953 struct ieee80211_mgmt *mgmt, 954 size_t len) 955 { 956 u16 auth_alg, auth_transaction; 957 958 sdata_assert_lock(sdata); 959 960 if (len < 24 + 6) 961 return; 962 963 auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg); 964 auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction); 965 966 ibss_dbg(sdata, 967 "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n", 968 mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction); 969 970 if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1) 971 return; 972 973 /* 974 * IEEE 802.11 standard does not require authentication in IBSS 975 * networks and most implementations do not seem to use it. 976 * However, try to reply to authentication attempts if someone 977 * has actually implemented this. 978 */ 979 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0, 980 mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0); 981 } 982 983 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, 984 struct ieee80211_mgmt *mgmt, size_t len, 985 struct ieee80211_rx_status *rx_status, 986 struct ieee802_11_elems *elems) 987 { 988 struct ieee80211_local *local = sdata->local; 989 struct cfg80211_bss *cbss; 990 struct ieee80211_bss *bss; 991 struct sta_info *sta; 992 struct ieee80211_channel *channel; 993 u64 beacon_timestamp, rx_timestamp; 994 u32 supp_rates = 0; 995 enum ieee80211_band band = rx_status->band; 996 enum nl80211_bss_scan_width scan_width; 997 struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band]; 998 bool rates_updated = false; 999 1000 channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq); 1001 if (!channel) 1002 return; 1003 1004 if (sdata->vif.type == NL80211_IFTYPE_ADHOC && 1005 ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) { 1006 1007 rcu_read_lock(); 1008 sta = sta_info_get(sdata, mgmt->sa); 1009 1010 if (elems->supp_rates) { 1011 supp_rates = ieee80211_sta_get_rates(sdata, elems, 1012 band, NULL); 1013 if (sta) { 1014 u32 prev_rates; 1015 1016 prev_rates = sta->sta.supp_rates[band]; 1017 /* make sure mandatory rates are always added */ 1018 scan_width = NL80211_BSS_CHAN_WIDTH_20; 1019 if (rx_status->flag & RX_FLAG_5MHZ) 1020 scan_width = NL80211_BSS_CHAN_WIDTH_5; 1021 if (rx_status->flag & RX_FLAG_10MHZ) 1022 scan_width = NL80211_BSS_CHAN_WIDTH_10; 1023 1024 sta->sta.supp_rates[band] = supp_rates | 1025 ieee80211_mandatory_rates(sband, 1026 scan_width); 1027 if (sta->sta.supp_rates[band] != prev_rates) { 1028 ibss_dbg(sdata, 1029 "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n", 1030 sta->sta.addr, prev_rates, 1031 sta->sta.supp_rates[band]); 1032 rates_updated = true; 1033 } 1034 } else { 1035 rcu_read_unlock(); 1036 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, 1037 mgmt->sa, supp_rates); 1038 } 1039 } 1040 1041 if (sta && elems->wmm_info) 1042 sta->sta.wme = true; 1043 1044 if (sta && elems->ht_operation && elems->ht_cap_elem && 1045 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT && 1046 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 && 1047 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) { 1048 /* we both use HT */ 1049 struct ieee80211_ht_cap htcap_ie; 1050 struct cfg80211_chan_def chandef; 1051 1052 ieee80211_ht_oper_to_chandef(channel, 1053 elems->ht_operation, 1054 &chandef); 1055 1056 memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie)); 1057 1058 /* 1059 * fall back to HT20 if we don't use or use 1060 * the other extension channel 1061 */ 1062 if (chandef.center_freq1 != 1063 sdata->u.ibss.chandef.center_freq1) 1064 htcap_ie.cap_info &= 1065 cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40); 1066 1067 rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap( 1068 sdata, sband, &htcap_ie, sta); 1069 } 1070 1071 if (sta && rates_updated) { 1072 u32 changed = IEEE80211_RC_SUPP_RATES_CHANGED; 1073 u8 rx_nss = sta->sta.rx_nss; 1074 1075 /* Force rx_nss recalculation */ 1076 sta->sta.rx_nss = 0; 1077 rate_control_rate_init(sta); 1078 if (sta->sta.rx_nss != rx_nss) 1079 changed |= IEEE80211_RC_NSS_CHANGED; 1080 1081 drv_sta_rc_update(local, sdata, &sta->sta, changed); 1082 } 1083 1084 rcu_read_unlock(); 1085 } 1086 1087 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems, 1088 channel); 1089 if (!bss) 1090 return; 1091 1092 cbss = container_of((void *)bss, struct cfg80211_bss, priv); 1093 1094 /* same for beacon and probe response */ 1095 beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp); 1096 1097 /* check if we need to merge IBSS */ 1098 1099 /* not an IBSS */ 1100 if (!(cbss->capability & WLAN_CAPABILITY_IBSS)) 1101 goto put_bss; 1102 1103 /* different channel */ 1104 if (sdata->u.ibss.fixed_channel && 1105 sdata->u.ibss.chandef.chan != cbss->channel) 1106 goto put_bss; 1107 1108 /* different SSID */ 1109 if (elems->ssid_len != sdata->u.ibss.ssid_len || 1110 memcmp(elems->ssid, sdata->u.ibss.ssid, 1111 sdata->u.ibss.ssid_len)) 1112 goto put_bss; 1113 1114 /* process channel switch */ 1115 if (sdata->vif.csa_active || 1116 ieee80211_ibss_process_chanswitch(sdata, elems, true)) 1117 goto put_bss; 1118 1119 /* same BSSID */ 1120 if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid)) 1121 goto put_bss; 1122 1123 /* we use a fixed BSSID */ 1124 if (sdata->u.ibss.fixed_bssid) 1125 goto put_bss; 1126 1127 if (ieee80211_have_rx_timestamp(rx_status)) { 1128 /* time when timestamp field was received */ 1129 rx_timestamp = 1130 ieee80211_calculate_rx_timestamp(local, rx_status, 1131 len + FCS_LEN, 24); 1132 } else { 1133 /* 1134 * second best option: get current TSF 1135 * (will return -1 if not supported) 1136 */ 1137 rx_timestamp = drv_get_tsf(local, sdata); 1138 } 1139 1140 ibss_dbg(sdata, 1141 "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n", 1142 mgmt->sa, mgmt->bssid, 1143 (unsigned long long)rx_timestamp, 1144 (unsigned long long)beacon_timestamp, 1145 (unsigned long long)(rx_timestamp - beacon_timestamp), 1146 jiffies); 1147 1148 if (beacon_timestamp > rx_timestamp) { 1149 ibss_dbg(sdata, 1150 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n", 1151 mgmt->bssid); 1152 ieee80211_sta_join_ibss(sdata, bss); 1153 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL); 1154 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 1155 supp_rates); 1156 rcu_read_unlock(); 1157 } 1158 1159 put_bss: 1160 ieee80211_rx_bss_put(local, bss); 1161 } 1162 1163 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata, 1164 const u8 *bssid, const u8 *addr, 1165 u32 supp_rates) 1166 { 1167 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1168 struct ieee80211_local *local = sdata->local; 1169 struct sta_info *sta; 1170 struct ieee80211_chanctx_conf *chanctx_conf; 1171 struct ieee80211_supported_band *sband; 1172 enum nl80211_bss_scan_width scan_width; 1173 int band; 1174 1175 /* 1176 * XXX: Consider removing the least recently used entry and 1177 * allow new one to be added. 1178 */ 1179 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 1180 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n", 1181 sdata->name, addr); 1182 return; 1183 } 1184 1185 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) 1186 return; 1187 1188 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) 1189 return; 1190 1191 rcu_read_lock(); 1192 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); 1193 if (WARN_ON_ONCE(!chanctx_conf)) { 1194 rcu_read_unlock(); 1195 return; 1196 } 1197 band = chanctx_conf->def.chan->band; 1198 scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def); 1199 rcu_read_unlock(); 1200 1201 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC); 1202 if (!sta) 1203 return; 1204 1205 sta->last_rx = jiffies; 1206 1207 /* make sure mandatory rates are always added */ 1208 sband = local->hw.wiphy->bands[band]; 1209 sta->sta.supp_rates[band] = supp_rates | 1210 ieee80211_mandatory_rates(sband, scan_width); 1211 1212 spin_lock(&ifibss->incomplete_lock); 1213 list_add(&sta->list, &ifibss->incomplete_stations); 1214 spin_unlock(&ifibss->incomplete_lock); 1215 ieee80211_queue_work(&local->hw, &sdata->work); 1216 } 1217 1218 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata) 1219 { 1220 struct ieee80211_local *local = sdata->local; 1221 struct sta_info *sta, *tmp; 1222 unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT; 1223 unsigned long exp_rsn_time = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT; 1224 1225 mutex_lock(&local->sta_mtx); 1226 1227 list_for_each_entry_safe(sta, tmp, &local->sta_list, list) { 1228 if (sdata != sta->sdata) 1229 continue; 1230 1231 if (time_after(jiffies, sta->last_rx + exp_time) || 1232 (time_after(jiffies, sta->last_rx + exp_rsn_time) && 1233 sta->sta_state != IEEE80211_STA_AUTHORIZED)) { 1234 sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n", 1235 sta->sta_state != IEEE80211_STA_AUTHORIZED ? 1236 "not authorized " : "", sta->sta.addr); 1237 1238 WARN_ON(__sta_info_destroy(sta)); 1239 } 1240 } 1241 1242 mutex_unlock(&local->sta_mtx); 1243 } 1244 1245 /* 1246 * This function is called with state == IEEE80211_IBSS_MLME_JOINED 1247 */ 1248 1249 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata) 1250 { 1251 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1252 enum nl80211_bss_scan_width scan_width; 1253 1254 sdata_assert_lock(sdata); 1255 1256 mod_timer(&ifibss->timer, 1257 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 1258 1259 ieee80211_ibss_sta_expire(sdata); 1260 1261 if (time_before(jiffies, ifibss->last_scan_completed + 1262 IEEE80211_IBSS_MERGE_INTERVAL)) 1263 return; 1264 1265 if (ieee80211_sta_active_ibss(sdata)) 1266 return; 1267 1268 if (ifibss->fixed_channel) 1269 return; 1270 1271 sdata_info(sdata, 1272 "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n"); 1273 1274 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef); 1275 ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len, 1276 NULL, scan_width); 1277 } 1278 1279 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata) 1280 { 1281 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1282 u8 bssid[ETH_ALEN]; 1283 u16 capability; 1284 int i; 1285 1286 sdata_assert_lock(sdata); 1287 1288 if (ifibss->fixed_bssid) { 1289 memcpy(bssid, ifibss->bssid, ETH_ALEN); 1290 } else { 1291 /* Generate random, not broadcast, locally administered BSSID. Mix in 1292 * own MAC address to make sure that devices that do not have proper 1293 * random number generator get different BSSID. */ 1294 get_random_bytes(bssid, ETH_ALEN); 1295 for (i = 0; i < ETH_ALEN; i++) 1296 bssid[i] ^= sdata->vif.addr[i]; 1297 bssid[0] &= ~0x01; 1298 bssid[0] |= 0x02; 1299 } 1300 1301 sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid); 1302 1303 capability = WLAN_CAPABILITY_IBSS; 1304 1305 if (ifibss->privacy) 1306 capability |= WLAN_CAPABILITY_PRIVACY; 1307 else 1308 sdata->drop_unencrypted = 0; 1309 1310 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int, 1311 &ifibss->chandef, ifibss->basic_rates, 1312 capability, 0, true); 1313 } 1314 1315 /* 1316 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH 1317 */ 1318 1319 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata) 1320 { 1321 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1322 struct ieee80211_local *local = sdata->local; 1323 struct cfg80211_bss *cbss; 1324 struct ieee80211_channel *chan = NULL; 1325 const u8 *bssid = NULL; 1326 enum nl80211_bss_scan_width scan_width; 1327 int active_ibss; 1328 u16 capability; 1329 1330 sdata_assert_lock(sdata); 1331 1332 active_ibss = ieee80211_sta_active_ibss(sdata); 1333 ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss); 1334 1335 if (active_ibss) 1336 return; 1337 1338 capability = WLAN_CAPABILITY_IBSS; 1339 if (ifibss->privacy) 1340 capability |= WLAN_CAPABILITY_PRIVACY; 1341 if (ifibss->fixed_bssid) 1342 bssid = ifibss->bssid; 1343 if (ifibss->fixed_channel) 1344 chan = ifibss->chandef.chan; 1345 if (!is_zero_ether_addr(ifibss->bssid)) 1346 bssid = ifibss->bssid; 1347 cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid, 1348 ifibss->ssid, ifibss->ssid_len, 1349 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY, 1350 capability); 1351 1352 if (cbss) { 1353 struct ieee80211_bss *bss; 1354 1355 bss = (void *)cbss->priv; 1356 ibss_dbg(sdata, 1357 "sta_find_ibss: selected %pM current %pM\n", 1358 cbss->bssid, ifibss->bssid); 1359 sdata_info(sdata, 1360 "Selected IBSS BSSID %pM based on configured SSID\n", 1361 cbss->bssid); 1362 1363 ieee80211_sta_join_ibss(sdata, bss); 1364 ieee80211_rx_bss_put(local, bss); 1365 return; 1366 } 1367 1368 /* if a fixed bssid and a fixed freq have been provided create the IBSS 1369 * directly and do not waste time scanning 1370 */ 1371 if (ifibss->fixed_bssid && ifibss->fixed_channel) { 1372 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n", 1373 bssid); 1374 ieee80211_sta_create_ibss(sdata); 1375 return; 1376 } 1377 1378 1379 ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n"); 1380 1381 /* Selected IBSS not found in current scan results - try to scan */ 1382 if (time_after(jiffies, ifibss->last_scan_completed + 1383 IEEE80211_SCAN_INTERVAL)) { 1384 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n"); 1385 1386 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef); 1387 ieee80211_request_ibss_scan(sdata, ifibss->ssid, 1388 ifibss->ssid_len, chan, 1389 scan_width); 1390 } else { 1391 int interval = IEEE80211_SCAN_INTERVAL; 1392 1393 if (time_after(jiffies, ifibss->ibss_join_req + 1394 IEEE80211_IBSS_JOIN_TIMEOUT)) 1395 ieee80211_sta_create_ibss(sdata); 1396 1397 mod_timer(&ifibss->timer, 1398 round_jiffies(jiffies + interval)); 1399 } 1400 } 1401 1402 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata, 1403 struct sk_buff *req) 1404 { 1405 struct ieee80211_mgmt *mgmt = (void *)req->data; 1406 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1407 struct ieee80211_local *local = sdata->local; 1408 int tx_last_beacon, len = req->len; 1409 struct sk_buff *skb; 1410 struct beacon_data *presp; 1411 u8 *pos, *end; 1412 1413 sdata_assert_lock(sdata); 1414 1415 presp = rcu_dereference_protected(ifibss->presp, 1416 lockdep_is_held(&sdata->wdev.mtx)); 1417 1418 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED || 1419 len < 24 + 2 || !presp) 1420 return; 1421 1422 tx_last_beacon = drv_tx_last_beacon(local); 1423 1424 ibss_dbg(sdata, 1425 "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n", 1426 mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon); 1427 1428 if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da)) 1429 return; 1430 1431 if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) && 1432 !is_broadcast_ether_addr(mgmt->bssid)) 1433 return; 1434 1435 end = ((u8 *) mgmt) + len; 1436 pos = mgmt->u.probe_req.variable; 1437 if (pos[0] != WLAN_EID_SSID || 1438 pos + 2 + pos[1] > end) { 1439 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n", 1440 mgmt->sa); 1441 return; 1442 } 1443 if (pos[1] != 0 && 1444 (pos[1] != ifibss->ssid_len || 1445 memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) { 1446 /* Ignore ProbeReq for foreign SSID */ 1447 return; 1448 } 1449 1450 /* Reply with ProbeResp */ 1451 skb = dev_alloc_skb(local->tx_headroom + presp->head_len); 1452 if (!skb) 1453 return; 1454 1455 skb_reserve(skb, local->tx_headroom); 1456 memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len); 1457 1458 memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN); 1459 ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa); 1460 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 1461 1462 /* avoid excessive retries for probe request to wildcard SSIDs */ 1463 if (pos[1] == 0) 1464 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK; 1465 1466 ieee80211_tx_skb(sdata, skb); 1467 } 1468 1469 static 1470 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata, 1471 struct ieee80211_mgmt *mgmt, size_t len, 1472 struct ieee80211_rx_status *rx_status) 1473 { 1474 size_t baselen; 1475 struct ieee802_11_elems elems; 1476 1477 BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) != 1478 offsetof(typeof(mgmt->u.beacon), variable)); 1479 1480 /* 1481 * either beacon or probe_resp but the variable field is at the 1482 * same offset 1483 */ 1484 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt; 1485 if (baselen > len) 1486 return; 1487 1488 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen, 1489 false, &elems); 1490 1491 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems); 1492 } 1493 1494 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata, 1495 struct sk_buff *skb) 1496 { 1497 struct ieee80211_rx_status *rx_status; 1498 struct ieee80211_mgmt *mgmt; 1499 u16 fc; 1500 struct ieee802_11_elems elems; 1501 int ies_len; 1502 1503 rx_status = IEEE80211_SKB_RXCB(skb); 1504 mgmt = (struct ieee80211_mgmt *) skb->data; 1505 fc = le16_to_cpu(mgmt->frame_control); 1506 1507 sdata_lock(sdata); 1508 1509 if (!sdata->u.ibss.ssid_len) 1510 goto mgmt_out; /* not ready to merge yet */ 1511 1512 switch (fc & IEEE80211_FCTL_STYPE) { 1513 case IEEE80211_STYPE_PROBE_REQ: 1514 ieee80211_rx_mgmt_probe_req(sdata, skb); 1515 break; 1516 case IEEE80211_STYPE_PROBE_RESP: 1517 case IEEE80211_STYPE_BEACON: 1518 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len, 1519 rx_status); 1520 break; 1521 case IEEE80211_STYPE_AUTH: 1522 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len); 1523 break; 1524 case IEEE80211_STYPE_DEAUTH: 1525 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len); 1526 break; 1527 case IEEE80211_STYPE_ACTION: 1528 switch (mgmt->u.action.category) { 1529 case WLAN_CATEGORY_SPECTRUM_MGMT: 1530 ies_len = skb->len - 1531 offsetof(struct ieee80211_mgmt, 1532 u.action.u.chan_switch.variable); 1533 1534 if (ies_len < 0) 1535 break; 1536 1537 ieee802_11_parse_elems( 1538 mgmt->u.action.u.chan_switch.variable, 1539 ies_len, true, &elems); 1540 1541 if (elems.parse_error) 1542 break; 1543 1544 ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len, 1545 rx_status, &elems); 1546 break; 1547 } 1548 } 1549 1550 mgmt_out: 1551 sdata_unlock(sdata); 1552 } 1553 1554 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata) 1555 { 1556 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1557 struct sta_info *sta; 1558 1559 sdata_lock(sdata); 1560 1561 /* 1562 * Work could be scheduled after scan or similar 1563 * when we aren't even joined (or trying) with a 1564 * network. 1565 */ 1566 if (!ifibss->ssid_len) 1567 goto out; 1568 1569 spin_lock_bh(&ifibss->incomplete_lock); 1570 while (!list_empty(&ifibss->incomplete_stations)) { 1571 sta = list_first_entry(&ifibss->incomplete_stations, 1572 struct sta_info, list); 1573 list_del(&sta->list); 1574 spin_unlock_bh(&ifibss->incomplete_lock); 1575 1576 ieee80211_ibss_finish_sta(sta); 1577 rcu_read_unlock(); 1578 spin_lock_bh(&ifibss->incomplete_lock); 1579 } 1580 spin_unlock_bh(&ifibss->incomplete_lock); 1581 1582 switch (ifibss->state) { 1583 case IEEE80211_IBSS_MLME_SEARCH: 1584 ieee80211_sta_find_ibss(sdata); 1585 break; 1586 case IEEE80211_IBSS_MLME_JOINED: 1587 ieee80211_sta_merge_ibss(sdata); 1588 break; 1589 default: 1590 WARN_ON(1); 1591 break; 1592 } 1593 1594 out: 1595 sdata_unlock(sdata); 1596 } 1597 1598 static void ieee80211_ibss_timer(unsigned long data) 1599 { 1600 struct ieee80211_sub_if_data *sdata = 1601 (struct ieee80211_sub_if_data *) data; 1602 1603 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 1604 } 1605 1606 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata) 1607 { 1608 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1609 1610 setup_timer(&ifibss->timer, ieee80211_ibss_timer, 1611 (unsigned long) sdata); 1612 INIT_LIST_HEAD(&ifibss->incomplete_stations); 1613 spin_lock_init(&ifibss->incomplete_lock); 1614 INIT_WORK(&ifibss->csa_connection_drop_work, 1615 ieee80211_csa_connection_drop_work); 1616 } 1617 1618 /* scan finished notification */ 1619 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local) 1620 { 1621 struct ieee80211_sub_if_data *sdata; 1622 1623 mutex_lock(&local->iflist_mtx); 1624 list_for_each_entry(sdata, &local->interfaces, list) { 1625 if (!ieee80211_sdata_running(sdata)) 1626 continue; 1627 if (sdata->vif.type != NL80211_IFTYPE_ADHOC) 1628 continue; 1629 sdata->u.ibss.last_scan_completed = jiffies; 1630 ieee80211_queue_work(&local->hw, &sdata->work); 1631 } 1632 mutex_unlock(&local->iflist_mtx); 1633 } 1634 1635 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata, 1636 struct cfg80211_ibss_params *params) 1637 { 1638 u32 changed = 0; 1639 u32 rate_flags; 1640 struct ieee80211_supported_band *sband; 1641 enum ieee80211_chanctx_mode chanmode; 1642 struct ieee80211_local *local = sdata->local; 1643 int radar_detect_width = 0; 1644 int i; 1645 int ret; 1646 1647 ret = cfg80211_chandef_dfs_required(local->hw.wiphy, 1648 ¶ms->chandef, 1649 sdata->wdev.iftype); 1650 if (ret < 0) 1651 return ret; 1652 1653 if (ret > 0) { 1654 if (!params->userspace_handles_dfs) 1655 return -EINVAL; 1656 radar_detect_width = BIT(params->chandef.width); 1657 } 1658 1659 chanmode = (params->channel_fixed && !ret) ? 1660 IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE; 1661 1662 mutex_lock(&local->chanctx_mtx); 1663 ret = ieee80211_check_combinations(sdata, ¶ms->chandef, chanmode, 1664 radar_detect_width); 1665 mutex_unlock(&local->chanctx_mtx); 1666 if (ret < 0) 1667 return ret; 1668 1669 if (params->bssid) { 1670 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN); 1671 sdata->u.ibss.fixed_bssid = true; 1672 } else 1673 sdata->u.ibss.fixed_bssid = false; 1674 1675 sdata->u.ibss.privacy = params->privacy; 1676 sdata->u.ibss.control_port = params->control_port; 1677 sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs; 1678 sdata->u.ibss.basic_rates = params->basic_rates; 1679 sdata->u.ibss.last_scan_completed = jiffies; 1680 1681 /* fix basic_rates if channel does not support these rates */ 1682 rate_flags = ieee80211_chandef_rate_flags(¶ms->chandef); 1683 sband = local->hw.wiphy->bands[params->chandef.chan->band]; 1684 for (i = 0; i < sband->n_bitrates; i++) { 1685 if ((rate_flags & sband->bitrates[i].flags) != rate_flags) 1686 sdata->u.ibss.basic_rates &= ~BIT(i); 1687 } 1688 memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate, 1689 sizeof(params->mcast_rate)); 1690 1691 sdata->vif.bss_conf.beacon_int = params->beacon_interval; 1692 1693 sdata->u.ibss.chandef = params->chandef; 1694 sdata->u.ibss.fixed_channel = params->channel_fixed; 1695 1696 if (params->ie) { 1697 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len, 1698 GFP_KERNEL); 1699 if (sdata->u.ibss.ie) 1700 sdata->u.ibss.ie_len = params->ie_len; 1701 } 1702 1703 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; 1704 sdata->u.ibss.ibss_join_req = jiffies; 1705 1706 memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len); 1707 sdata->u.ibss.ssid_len = params->ssid_len; 1708 1709 memcpy(&sdata->u.ibss.ht_capa, ¶ms->ht_capa, 1710 sizeof(sdata->u.ibss.ht_capa)); 1711 memcpy(&sdata->u.ibss.ht_capa_mask, ¶ms->ht_capa_mask, 1712 sizeof(sdata->u.ibss.ht_capa_mask)); 1713 1714 /* 1715 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is 1716 * reserved, but an HT STA shall protect HT transmissions as though 1717 * the HT Protection field were set to non-HT mixed mode. 1718 * 1719 * In an IBSS, the RIFS Mode field of the HT Operation element is 1720 * also reserved, but an HT STA shall operate as though this field 1721 * were set to 1. 1722 */ 1723 1724 sdata->vif.bss_conf.ht_operation_mode |= 1725 IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED 1726 | IEEE80211_HT_PARAM_RIFS_MODE; 1727 1728 changed |= BSS_CHANGED_HT; 1729 ieee80211_bss_info_change_notify(sdata, changed); 1730 1731 sdata->smps_mode = IEEE80211_SMPS_OFF; 1732 sdata->needed_rx_chains = local->rx_chains; 1733 1734 ieee80211_queue_work(&local->hw, &sdata->work); 1735 1736 return 0; 1737 } 1738 1739 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata) 1740 { 1741 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1742 1743 ieee80211_ibss_disconnect(sdata); 1744 ifibss->ssid_len = 0; 1745 memset(ifibss->bssid, 0, ETH_ALEN); 1746 1747 /* remove beacon */ 1748 kfree(sdata->u.ibss.ie); 1749 1750 /* on the next join, re-program HT parameters */ 1751 memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa)); 1752 memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask)); 1753 1754 synchronize_rcu(); 1755 1756 skb_queue_purge(&sdata->skb_queue); 1757 1758 del_timer_sync(&sdata->u.ibss.timer); 1759 1760 return 0; 1761 } 1762