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_supported_band *sband; 224 struct ieee80211_mgmt *mgmt; 225 struct cfg80211_bss *bss; 226 u32 bss_change; 227 struct cfg80211_chan_def chandef; 228 struct ieee80211_channel *chan; 229 struct beacon_data *presp; 230 enum nl80211_bss_scan_width scan_width; 231 bool have_higher_than_11mbit; 232 bool radar_required = false; 233 int err; 234 235 sdata_assert_lock(sdata); 236 237 /* Reset own TSF to allow time synchronization work. */ 238 drv_reset_tsf(local, sdata); 239 240 if (!ether_addr_equal(ifibss->bssid, bssid)) 241 sta_info_flush(sdata); 242 243 /* if merging, indicate to driver that we leave the old IBSS */ 244 if (sdata->vif.bss_conf.ibss_joined) { 245 sdata->vif.bss_conf.ibss_joined = false; 246 sdata->vif.bss_conf.ibss_creator = false; 247 sdata->vif.bss_conf.enable_beacon = false; 248 netif_carrier_off(sdata->dev); 249 ieee80211_bss_info_change_notify(sdata, 250 BSS_CHANGED_IBSS | 251 BSS_CHANGED_BEACON_ENABLED); 252 drv_leave_ibss(local, sdata); 253 } 254 255 presp = rcu_dereference_protected(ifibss->presp, 256 lockdep_is_held(&sdata->wdev.mtx)); 257 rcu_assign_pointer(ifibss->presp, NULL); 258 if (presp) 259 kfree_rcu(presp, rcu_head); 260 261 sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0; 262 263 /* make a copy of the chandef, it could be modified below. */ 264 chandef = *req_chandef; 265 chan = chandef.chan; 266 if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) { 267 if (chandef.width == NL80211_CHAN_WIDTH_5 || 268 chandef.width == NL80211_CHAN_WIDTH_10 || 269 chandef.width == NL80211_CHAN_WIDTH_20_NOHT || 270 chandef.width == NL80211_CHAN_WIDTH_20) { 271 sdata_info(sdata, 272 "Failed to join IBSS, beacons forbidden\n"); 273 return; 274 } 275 chandef.width = NL80211_CHAN_WIDTH_20; 276 chandef.center_freq1 = chan->center_freq; 277 /* check again for downgraded chandef */ 278 if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) { 279 sdata_info(sdata, 280 "Failed to join IBSS, beacons forbidden\n"); 281 return; 282 } 283 } 284 285 err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy, 286 &chandef); 287 if (err > 0) { 288 if (!ifibss->userspace_handles_dfs) { 289 sdata_info(sdata, 290 "Failed to join IBSS, DFS channel without control program\n"); 291 return; 292 } 293 radar_required = true; 294 } 295 296 mutex_lock(&local->mtx); 297 ieee80211_vif_release_channel(sdata); 298 if (ieee80211_vif_use_channel(sdata, &chandef, 299 ifibss->fixed_channel ? 300 IEEE80211_CHANCTX_SHARED : 301 IEEE80211_CHANCTX_EXCLUSIVE)) { 302 sdata_info(sdata, "Failed to join IBSS, no channel context\n"); 303 mutex_unlock(&local->mtx); 304 return; 305 } 306 mutex_unlock(&local->mtx); 307 308 memcpy(ifibss->bssid, bssid, ETH_ALEN); 309 310 sband = local->hw.wiphy->bands[chan->band]; 311 312 presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates, 313 capability, tsf, &chandef, 314 &have_higher_than_11mbit, NULL); 315 if (!presp) 316 return; 317 318 rcu_assign_pointer(ifibss->presp, presp); 319 mgmt = (void *)presp->head; 320 321 sdata->radar_required = radar_required; 322 sdata->vif.bss_conf.enable_beacon = true; 323 sdata->vif.bss_conf.beacon_int = beacon_int; 324 sdata->vif.bss_conf.basic_rates = basic_rates; 325 sdata->vif.bss_conf.ssid_len = ifibss->ssid_len; 326 memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len); 327 bss_change = BSS_CHANGED_BEACON_INT; 328 bss_change |= ieee80211_reset_erp_info(sdata); 329 bss_change |= BSS_CHANGED_BSSID; 330 bss_change |= BSS_CHANGED_BEACON; 331 bss_change |= BSS_CHANGED_BEACON_ENABLED; 332 bss_change |= BSS_CHANGED_BASIC_RATES; 333 bss_change |= BSS_CHANGED_HT; 334 bss_change |= BSS_CHANGED_IBSS; 335 bss_change |= BSS_CHANGED_SSID; 336 337 /* 338 * In 5 GHz/802.11a, we can always use short slot time. 339 * (IEEE 802.11-2012 18.3.8.7) 340 * 341 * In 2.4GHz, we must always use long slots in IBSS for compatibility 342 * reasons. 343 * (IEEE 802.11-2012 19.4.5) 344 * 345 * HT follows these specifications (IEEE 802.11-2012 20.3.18) 346 */ 347 sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ; 348 bss_change |= BSS_CHANGED_ERP_SLOT; 349 350 /* cf. IEEE 802.11 9.2.12 */ 351 if (chan->band == IEEE80211_BAND_2GHZ && have_higher_than_11mbit) 352 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE; 353 else 354 sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE; 355 356 ieee80211_set_wmm_default(sdata, true); 357 358 sdata->vif.bss_conf.ibss_joined = true; 359 sdata->vif.bss_conf.ibss_creator = creator; 360 361 err = drv_join_ibss(local, sdata); 362 if (err) { 363 sdata->vif.bss_conf.ibss_joined = false; 364 sdata->vif.bss_conf.ibss_creator = false; 365 sdata->vif.bss_conf.enable_beacon = false; 366 sdata->vif.bss_conf.ssid_len = 0; 367 RCU_INIT_POINTER(ifibss->presp, NULL); 368 kfree_rcu(presp, rcu_head); 369 mutex_lock(&local->mtx); 370 ieee80211_vif_release_channel(sdata); 371 mutex_unlock(&local->mtx); 372 sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n", 373 err); 374 return; 375 } 376 377 ieee80211_bss_info_change_notify(sdata, bss_change); 378 379 ifibss->state = IEEE80211_IBSS_MLME_JOINED; 380 mod_timer(&ifibss->timer, 381 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 382 383 scan_width = cfg80211_chandef_to_scan_width(&chandef); 384 bss = cfg80211_inform_bss_width_frame(local->hw.wiphy, chan, 385 scan_width, mgmt, 386 presp->head_len, 0, GFP_KERNEL); 387 cfg80211_put_bss(local->hw.wiphy, bss); 388 netif_carrier_on(sdata->dev); 389 cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL); 390 } 391 392 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 393 struct ieee80211_bss *bss) 394 { 395 struct cfg80211_bss *cbss = 396 container_of((void *)bss, struct cfg80211_bss, priv); 397 struct ieee80211_supported_band *sband; 398 struct cfg80211_chan_def chandef; 399 u32 basic_rates; 400 int i, j; 401 u16 beacon_int = cbss->beacon_interval; 402 const struct cfg80211_bss_ies *ies; 403 enum nl80211_channel_type chan_type; 404 u64 tsf; 405 u32 rate_flags; 406 int shift; 407 408 sdata_assert_lock(sdata); 409 410 if (beacon_int < 10) 411 beacon_int = 10; 412 413 switch (sdata->u.ibss.chandef.width) { 414 case NL80211_CHAN_WIDTH_20_NOHT: 415 case NL80211_CHAN_WIDTH_20: 416 case NL80211_CHAN_WIDTH_40: 417 chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef); 418 cfg80211_chandef_create(&chandef, cbss->channel, chan_type); 419 break; 420 case NL80211_CHAN_WIDTH_5: 421 case NL80211_CHAN_WIDTH_10: 422 cfg80211_chandef_create(&chandef, cbss->channel, 423 NL80211_CHAN_WIDTH_20_NOHT); 424 chandef.width = sdata->u.ibss.chandef.width; 425 break; 426 default: 427 /* fall back to 20 MHz for unsupported modes */ 428 cfg80211_chandef_create(&chandef, cbss->channel, 429 NL80211_CHAN_WIDTH_20_NOHT); 430 break; 431 } 432 433 sband = sdata->local->hw.wiphy->bands[cbss->channel->band]; 434 rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef); 435 shift = ieee80211_vif_get_shift(&sdata->vif); 436 437 basic_rates = 0; 438 439 for (i = 0; i < bss->supp_rates_len; i++) { 440 int rate = bss->supp_rates[i] & 0x7f; 441 bool is_basic = !!(bss->supp_rates[i] & 0x80); 442 443 for (j = 0; j < sband->n_bitrates; j++) { 444 int brate; 445 if ((rate_flags & sband->bitrates[j].flags) 446 != rate_flags) 447 continue; 448 449 brate = DIV_ROUND_UP(sband->bitrates[j].bitrate, 450 5 * (1 << shift)); 451 if (brate == rate) { 452 if (is_basic) 453 basic_rates |= BIT(j); 454 break; 455 } 456 } 457 } 458 459 rcu_read_lock(); 460 ies = rcu_dereference(cbss->ies); 461 tsf = ies->tsf; 462 rcu_read_unlock(); 463 464 __ieee80211_sta_join_ibss(sdata, cbss->bssid, 465 beacon_int, 466 &chandef, 467 basic_rates, 468 cbss->capability, 469 tsf, false); 470 } 471 472 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata, 473 struct cfg80211_csa_settings *csa_settings) 474 { 475 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 476 struct beacon_data *presp, *old_presp; 477 struct cfg80211_bss *cbss; 478 const struct cfg80211_bss_ies *ies; 479 u16 capability; 480 u64 tsf; 481 int ret = 0; 482 483 sdata_assert_lock(sdata); 484 485 capability = WLAN_CAPABILITY_IBSS; 486 487 if (ifibss->privacy) 488 capability |= WLAN_CAPABILITY_PRIVACY; 489 490 cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan, 491 ifibss->bssid, ifibss->ssid, 492 ifibss->ssid_len, WLAN_CAPABILITY_IBSS | 493 WLAN_CAPABILITY_PRIVACY, 494 capability); 495 496 if (WARN_ON(!cbss)) { 497 ret = -EINVAL; 498 goto out; 499 } 500 501 rcu_read_lock(); 502 ies = rcu_dereference(cbss->ies); 503 tsf = ies->tsf; 504 rcu_read_unlock(); 505 cfg80211_put_bss(sdata->local->hw.wiphy, cbss); 506 507 old_presp = rcu_dereference_protected(ifibss->presp, 508 lockdep_is_held(&sdata->wdev.mtx)); 509 510 presp = ieee80211_ibss_build_presp(sdata, 511 sdata->vif.bss_conf.beacon_int, 512 sdata->vif.bss_conf.basic_rates, 513 capability, tsf, &ifibss->chandef, 514 NULL, csa_settings); 515 if (!presp) { 516 ret = -ENOMEM; 517 goto out; 518 } 519 520 rcu_assign_pointer(ifibss->presp, presp); 521 if (old_presp) 522 kfree_rcu(old_presp, rcu_head); 523 524 /* it might not send the beacon for a while. send an action frame 525 * immediately to announce the channel switch. 526 */ 527 if (csa_settings) 528 ieee80211_send_action_csa(sdata, csa_settings); 529 530 return BSS_CHANGED_BEACON; 531 out: 532 return ret; 533 } 534 535 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata) 536 { 537 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 538 struct cfg80211_bss *cbss; 539 int err; 540 u16 capability; 541 542 sdata_assert_lock(sdata); 543 544 /* update cfg80211 bss information with the new channel */ 545 if (!is_zero_ether_addr(ifibss->bssid)) { 546 capability = WLAN_CAPABILITY_IBSS; 547 548 if (ifibss->privacy) 549 capability |= WLAN_CAPABILITY_PRIVACY; 550 551 cbss = cfg80211_get_bss(sdata->local->hw.wiphy, 552 ifibss->chandef.chan, 553 ifibss->bssid, ifibss->ssid, 554 ifibss->ssid_len, WLAN_CAPABILITY_IBSS | 555 WLAN_CAPABILITY_PRIVACY, 556 capability); 557 /* XXX: should not really modify cfg80211 data */ 558 if (cbss) { 559 cbss->channel = sdata->csa_chandef.chan; 560 cfg80211_put_bss(sdata->local->hw.wiphy, cbss); 561 } 562 } 563 564 ifibss->chandef = sdata->csa_chandef; 565 566 /* generate the beacon */ 567 err = ieee80211_ibss_csa_beacon(sdata, NULL); 568 if (err < 0) 569 return err; 570 571 if (err) 572 ieee80211_bss_info_change_notify(sdata, err); 573 574 return 0; 575 } 576 577 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata) 578 { 579 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 580 581 cancel_work_sync(&ifibss->csa_connection_drop_work); 582 } 583 584 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta) 585 __acquires(RCU) 586 { 587 struct ieee80211_sub_if_data *sdata = sta->sdata; 588 u8 addr[ETH_ALEN]; 589 590 memcpy(addr, sta->sta.addr, ETH_ALEN); 591 592 ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr); 593 594 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH); 595 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC); 596 /* authorize the station only if the network is not RSN protected. If 597 * not wait for the userspace to authorize it */ 598 if (!sta->sdata->u.ibss.control_port) 599 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED); 600 601 rate_control_rate_init(sta); 602 603 /* If it fails, maybe we raced another insertion? */ 604 if (sta_info_insert_rcu(sta)) 605 return sta_info_get(sdata, addr); 606 return sta; 607 } 608 609 static struct sta_info * 610 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid, 611 const u8 *addr, u32 supp_rates) 612 __acquires(RCU) 613 { 614 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 615 struct ieee80211_local *local = sdata->local; 616 struct sta_info *sta; 617 struct ieee80211_chanctx_conf *chanctx_conf; 618 struct ieee80211_supported_band *sband; 619 enum nl80211_bss_scan_width scan_width; 620 int band; 621 622 /* 623 * XXX: Consider removing the least recently used entry and 624 * allow new one to be added. 625 */ 626 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 627 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n", 628 sdata->name, addr); 629 rcu_read_lock(); 630 return NULL; 631 } 632 633 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) { 634 rcu_read_lock(); 635 return NULL; 636 } 637 638 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) { 639 rcu_read_lock(); 640 return NULL; 641 } 642 643 rcu_read_lock(); 644 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); 645 if (WARN_ON_ONCE(!chanctx_conf)) 646 return NULL; 647 band = chanctx_conf->def.chan->band; 648 scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def); 649 rcu_read_unlock(); 650 651 sta = sta_info_alloc(sdata, addr, GFP_KERNEL); 652 if (!sta) { 653 rcu_read_lock(); 654 return NULL; 655 } 656 657 sta->last_rx = jiffies; 658 659 /* make sure mandatory rates are always added */ 660 sband = local->hw.wiphy->bands[band]; 661 sta->sta.supp_rates[band] = supp_rates | 662 ieee80211_mandatory_rates(sband, scan_width); 663 664 return ieee80211_ibss_finish_sta(sta); 665 } 666 667 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata) 668 { 669 struct ieee80211_local *local = sdata->local; 670 int active = 0; 671 struct sta_info *sta; 672 673 sdata_assert_lock(sdata); 674 675 rcu_read_lock(); 676 677 list_for_each_entry_rcu(sta, &local->sta_list, list) { 678 if (sta->sdata == sdata && 679 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL, 680 jiffies)) { 681 active++; 682 break; 683 } 684 } 685 686 rcu_read_unlock(); 687 688 return active; 689 } 690 691 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata) 692 { 693 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 694 struct ieee80211_local *local = sdata->local; 695 struct cfg80211_bss *cbss; 696 struct beacon_data *presp; 697 struct sta_info *sta; 698 int active_ibss; 699 u16 capability; 700 701 active_ibss = ieee80211_sta_active_ibss(sdata); 702 703 if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) { 704 capability = WLAN_CAPABILITY_IBSS; 705 706 if (ifibss->privacy) 707 capability |= WLAN_CAPABILITY_PRIVACY; 708 709 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan, 710 ifibss->bssid, ifibss->ssid, 711 ifibss->ssid_len, WLAN_CAPABILITY_IBSS | 712 WLAN_CAPABILITY_PRIVACY, 713 capability); 714 715 if (cbss) { 716 cfg80211_unlink_bss(local->hw.wiphy, cbss); 717 cfg80211_put_bss(sdata->local->hw.wiphy, cbss); 718 } 719 } 720 721 ifibss->state = IEEE80211_IBSS_MLME_SEARCH; 722 723 sta_info_flush(sdata); 724 725 spin_lock_bh(&ifibss->incomplete_lock); 726 while (!list_empty(&ifibss->incomplete_stations)) { 727 sta = list_first_entry(&ifibss->incomplete_stations, 728 struct sta_info, list); 729 list_del(&sta->list); 730 spin_unlock_bh(&ifibss->incomplete_lock); 731 732 sta_info_free(local, sta); 733 spin_lock_bh(&ifibss->incomplete_lock); 734 } 735 spin_unlock_bh(&ifibss->incomplete_lock); 736 737 netif_carrier_off(sdata->dev); 738 739 sdata->vif.bss_conf.ibss_joined = false; 740 sdata->vif.bss_conf.ibss_creator = false; 741 sdata->vif.bss_conf.enable_beacon = false; 742 sdata->vif.bss_conf.ssid_len = 0; 743 744 /* remove beacon */ 745 presp = rcu_dereference_protected(ifibss->presp, 746 lockdep_is_held(&sdata->wdev.mtx)); 747 RCU_INIT_POINTER(sdata->u.ibss.presp, NULL); 748 if (presp) 749 kfree_rcu(presp, rcu_head); 750 751 clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state); 752 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED | 753 BSS_CHANGED_IBSS); 754 drv_leave_ibss(local, sdata); 755 mutex_lock(&local->mtx); 756 ieee80211_vif_release_channel(sdata); 757 mutex_unlock(&local->mtx); 758 } 759 760 static void ieee80211_csa_connection_drop_work(struct work_struct *work) 761 { 762 struct ieee80211_sub_if_data *sdata = 763 container_of(work, struct ieee80211_sub_if_data, 764 u.ibss.csa_connection_drop_work); 765 766 sdata_lock(sdata); 767 768 ieee80211_ibss_disconnect(sdata); 769 synchronize_rcu(); 770 skb_queue_purge(&sdata->skb_queue); 771 772 /* trigger a scan to find another IBSS network to join */ 773 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 774 775 sdata_unlock(sdata); 776 } 777 778 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata) 779 { 780 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 781 int err; 782 783 /* if the current channel is a DFS channel, mark the channel as 784 * unavailable. 785 */ 786 err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy, 787 &ifibss->chandef); 788 if (err > 0) 789 cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef, 790 GFP_ATOMIC); 791 } 792 793 static bool 794 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata, 795 struct ieee802_11_elems *elems, 796 bool beacon) 797 { 798 struct cfg80211_csa_settings params; 799 struct ieee80211_csa_ie csa_ie; 800 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 801 enum nl80211_channel_type ch_type; 802 int err; 803 u32 sta_flags; 804 805 sta_flags = IEEE80211_STA_DISABLE_VHT; 806 switch (ifibss->chandef.width) { 807 case NL80211_CHAN_WIDTH_5: 808 case NL80211_CHAN_WIDTH_10: 809 case NL80211_CHAN_WIDTH_20_NOHT: 810 sta_flags |= IEEE80211_STA_DISABLE_HT; 811 /* fall through */ 812 case NL80211_CHAN_WIDTH_20: 813 sta_flags |= IEEE80211_STA_DISABLE_40MHZ; 814 break; 815 default: 816 break; 817 } 818 819 memset(¶ms, 0, sizeof(params)); 820 memset(&csa_ie, 0, sizeof(csa_ie)); 821 err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon, 822 ifibss->chandef.chan->band, 823 sta_flags, ifibss->bssid, &csa_ie); 824 /* can't switch to destination channel, fail */ 825 if (err < 0) 826 goto disconnect; 827 828 /* did not contain a CSA */ 829 if (err) 830 return false; 831 832 /* channel switch is not supported, disconnect */ 833 if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH)) 834 goto disconnect; 835 836 params.count = csa_ie.count; 837 params.chandef = csa_ie.chandef; 838 839 switch (ifibss->chandef.width) { 840 case NL80211_CHAN_WIDTH_20_NOHT: 841 case NL80211_CHAN_WIDTH_20: 842 case NL80211_CHAN_WIDTH_40: 843 /* keep our current HT mode (HT20/HT40+/HT40-), even if 844 * another mode has been announced. The mode is not adopted 845 * within the beacon while doing CSA and we should therefore 846 * keep the mode which we announce. 847 */ 848 ch_type = cfg80211_get_chandef_type(&ifibss->chandef); 849 cfg80211_chandef_create(¶ms.chandef, params.chandef.chan, 850 ch_type); 851 break; 852 case NL80211_CHAN_WIDTH_5: 853 case NL80211_CHAN_WIDTH_10: 854 if (params.chandef.width != ifibss->chandef.width) { 855 sdata_info(sdata, 856 "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n", 857 ifibss->bssid, 858 params.chandef.chan->center_freq, 859 params.chandef.width, 860 params.chandef.center_freq1, 861 params.chandef.center_freq2); 862 goto disconnect; 863 } 864 break; 865 default: 866 /* should not happen, sta_flags should prevent VHT modes. */ 867 WARN_ON(1); 868 goto disconnect; 869 } 870 871 if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, ¶ms.chandef)) { 872 sdata_info(sdata, 873 "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n", 874 ifibss->bssid, 875 params.chandef.chan->center_freq, 876 params.chandef.width, 877 params.chandef.center_freq1, 878 params.chandef.center_freq2); 879 goto disconnect; 880 } 881 882 err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy, 883 ¶ms.chandef); 884 if (err < 0) 885 goto disconnect; 886 if (err) { 887 /* IBSS-DFS only allowed with a control program */ 888 if (!ifibss->userspace_handles_dfs) 889 goto disconnect; 890 891 params.radar_required = true; 892 } 893 894 if (cfg80211_chandef_identical(¶ms.chandef, 895 &sdata->vif.bss_conf.chandef)) { 896 ibss_dbg(sdata, 897 "received csa with an identical chandef, ignoring\n"); 898 return true; 899 } 900 901 /* all checks done, now perform the channel switch. */ 902 ibss_dbg(sdata, 903 "received channel switch announcement to go to channel %d MHz\n", 904 params.chandef.chan->center_freq); 905 906 params.block_tx = !!csa_ie.mode; 907 908 if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev, 909 ¶ms)) 910 goto disconnect; 911 912 ieee80211_ibss_csa_mark_radar(sdata); 913 914 return true; 915 disconnect: 916 ibss_dbg(sdata, "Can't handle channel switch, disconnect\n"); 917 ieee80211_queue_work(&sdata->local->hw, 918 &ifibss->csa_connection_drop_work); 919 920 ieee80211_ibss_csa_mark_radar(sdata); 921 922 return true; 923 } 924 925 static void 926 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata, 927 struct ieee80211_mgmt *mgmt, size_t len, 928 struct ieee80211_rx_status *rx_status, 929 struct ieee802_11_elems *elems) 930 { 931 int required_len; 932 933 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 934 return; 935 936 /* CSA is the only action we handle for now */ 937 if (mgmt->u.action.u.measurement.action_code != 938 WLAN_ACTION_SPCT_CHL_SWITCH) 939 return; 940 941 required_len = IEEE80211_MIN_ACTION_SIZE + 942 sizeof(mgmt->u.action.u.chan_switch); 943 if (len < required_len) 944 return; 945 946 if (!sdata->vif.csa_active) 947 ieee80211_ibss_process_chanswitch(sdata, elems, false); 948 } 949 950 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata, 951 struct ieee80211_mgmt *mgmt, 952 size_t len) 953 { 954 u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code); 955 956 if (len < IEEE80211_DEAUTH_FRAME_LEN) 957 return; 958 959 ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n", 960 mgmt->sa, mgmt->da, mgmt->bssid, reason); 961 sta_info_destroy_addr(sdata, mgmt->sa); 962 } 963 964 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata, 965 struct ieee80211_mgmt *mgmt, 966 size_t len) 967 { 968 u16 auth_alg, auth_transaction; 969 970 sdata_assert_lock(sdata); 971 972 if (len < 24 + 6) 973 return; 974 975 auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg); 976 auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction); 977 978 ibss_dbg(sdata, 979 "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n", 980 mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction); 981 982 if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1) 983 return; 984 985 /* 986 * IEEE 802.11 standard does not require authentication in IBSS 987 * networks and most implementations do not seem to use it. 988 * However, try to reply to authentication attempts if someone 989 * has actually implemented this. 990 */ 991 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0, 992 mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0); 993 } 994 995 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, 996 struct ieee80211_mgmt *mgmt, size_t len, 997 struct ieee80211_rx_status *rx_status, 998 struct ieee802_11_elems *elems) 999 { 1000 struct ieee80211_local *local = sdata->local; 1001 int freq; 1002 struct cfg80211_bss *cbss; 1003 struct ieee80211_bss *bss; 1004 struct sta_info *sta; 1005 struct ieee80211_channel *channel; 1006 u64 beacon_timestamp, rx_timestamp; 1007 u32 supp_rates = 0; 1008 enum ieee80211_band band = rx_status->band; 1009 enum nl80211_bss_scan_width scan_width; 1010 struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band]; 1011 bool rates_updated = false; 1012 1013 if (elems->ds_params) 1014 freq = ieee80211_channel_to_frequency(elems->ds_params[0], 1015 band); 1016 else 1017 freq = rx_status->freq; 1018 1019 channel = ieee80211_get_channel(local->hw.wiphy, freq); 1020 1021 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 1022 return; 1023 1024 if (sdata->vif.type == NL80211_IFTYPE_ADHOC && 1025 ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) { 1026 1027 rcu_read_lock(); 1028 sta = sta_info_get(sdata, mgmt->sa); 1029 1030 if (elems->supp_rates) { 1031 supp_rates = ieee80211_sta_get_rates(sdata, elems, 1032 band, NULL); 1033 if (sta) { 1034 u32 prev_rates; 1035 1036 prev_rates = sta->sta.supp_rates[band]; 1037 /* make sure mandatory rates are always added */ 1038 scan_width = NL80211_BSS_CHAN_WIDTH_20; 1039 if (rx_status->flag & RX_FLAG_5MHZ) 1040 scan_width = NL80211_BSS_CHAN_WIDTH_5; 1041 if (rx_status->flag & RX_FLAG_10MHZ) 1042 scan_width = NL80211_BSS_CHAN_WIDTH_10; 1043 1044 sta->sta.supp_rates[band] = supp_rates | 1045 ieee80211_mandatory_rates(sband, 1046 scan_width); 1047 if (sta->sta.supp_rates[band] != prev_rates) { 1048 ibss_dbg(sdata, 1049 "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n", 1050 sta->sta.addr, prev_rates, 1051 sta->sta.supp_rates[band]); 1052 rates_updated = true; 1053 } 1054 } else { 1055 rcu_read_unlock(); 1056 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, 1057 mgmt->sa, supp_rates); 1058 } 1059 } 1060 1061 if (sta && elems->wmm_info) 1062 set_sta_flag(sta, WLAN_STA_WME); 1063 1064 if (sta && elems->ht_operation && elems->ht_cap_elem && 1065 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT && 1066 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 && 1067 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) { 1068 /* we both use HT */ 1069 struct ieee80211_ht_cap htcap_ie; 1070 struct cfg80211_chan_def chandef; 1071 1072 ieee80211_ht_oper_to_chandef(channel, 1073 elems->ht_operation, 1074 &chandef); 1075 1076 memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie)); 1077 1078 /* 1079 * fall back to HT20 if we don't use or use 1080 * the other extension channel 1081 */ 1082 if (chandef.center_freq1 != 1083 sdata->u.ibss.chandef.center_freq1) 1084 htcap_ie.cap_info &= 1085 cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40); 1086 1087 rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap( 1088 sdata, sband, &htcap_ie, sta); 1089 } 1090 1091 if (sta && rates_updated) { 1092 drv_sta_rc_update(local, sdata, &sta->sta, 1093 IEEE80211_RC_SUPP_RATES_CHANGED); 1094 rate_control_rate_init(sta); 1095 } 1096 1097 rcu_read_unlock(); 1098 } 1099 1100 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems, 1101 channel); 1102 if (!bss) 1103 return; 1104 1105 cbss = container_of((void *)bss, struct cfg80211_bss, priv); 1106 1107 /* same for beacon and probe response */ 1108 beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp); 1109 1110 /* check if we need to merge IBSS */ 1111 1112 /* not an IBSS */ 1113 if (!(cbss->capability & WLAN_CAPABILITY_IBSS)) 1114 goto put_bss; 1115 1116 /* different channel */ 1117 if (sdata->u.ibss.fixed_channel && 1118 sdata->u.ibss.chandef.chan != cbss->channel) 1119 goto put_bss; 1120 1121 /* different SSID */ 1122 if (elems->ssid_len != sdata->u.ibss.ssid_len || 1123 memcmp(elems->ssid, sdata->u.ibss.ssid, 1124 sdata->u.ibss.ssid_len)) 1125 goto put_bss; 1126 1127 /* process channel switch */ 1128 if (sdata->vif.csa_active || 1129 ieee80211_ibss_process_chanswitch(sdata, elems, true)) 1130 goto put_bss; 1131 1132 /* same BSSID */ 1133 if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid)) 1134 goto put_bss; 1135 1136 /* we use a fixed BSSID */ 1137 if (sdata->u.ibss.fixed_bssid) 1138 goto put_bss; 1139 1140 if (ieee80211_have_rx_timestamp(rx_status)) { 1141 /* time when timestamp field was received */ 1142 rx_timestamp = 1143 ieee80211_calculate_rx_timestamp(local, rx_status, 1144 len + FCS_LEN, 24); 1145 } else { 1146 /* 1147 * second best option: get current TSF 1148 * (will return -1 if not supported) 1149 */ 1150 rx_timestamp = drv_get_tsf(local, sdata); 1151 } 1152 1153 ibss_dbg(sdata, 1154 "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n", 1155 mgmt->sa, mgmt->bssid, 1156 (unsigned long long)rx_timestamp, 1157 (unsigned long long)beacon_timestamp, 1158 (unsigned long long)(rx_timestamp - beacon_timestamp), 1159 jiffies); 1160 1161 if (beacon_timestamp > rx_timestamp) { 1162 ibss_dbg(sdata, 1163 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n", 1164 mgmt->bssid); 1165 ieee80211_sta_join_ibss(sdata, bss); 1166 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL); 1167 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 1168 supp_rates); 1169 rcu_read_unlock(); 1170 } 1171 1172 put_bss: 1173 ieee80211_rx_bss_put(local, bss); 1174 } 1175 1176 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata, 1177 const u8 *bssid, const u8 *addr, 1178 u32 supp_rates) 1179 { 1180 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1181 struct ieee80211_local *local = sdata->local; 1182 struct sta_info *sta; 1183 struct ieee80211_chanctx_conf *chanctx_conf; 1184 struct ieee80211_supported_band *sband; 1185 enum nl80211_bss_scan_width scan_width; 1186 int band; 1187 1188 /* 1189 * XXX: Consider removing the least recently used entry and 1190 * allow new one to be added. 1191 */ 1192 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 1193 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n", 1194 sdata->name, addr); 1195 return; 1196 } 1197 1198 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) 1199 return; 1200 1201 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) 1202 return; 1203 1204 rcu_read_lock(); 1205 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); 1206 if (WARN_ON_ONCE(!chanctx_conf)) { 1207 rcu_read_unlock(); 1208 return; 1209 } 1210 band = chanctx_conf->def.chan->band; 1211 scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def); 1212 rcu_read_unlock(); 1213 1214 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC); 1215 if (!sta) 1216 return; 1217 1218 sta->last_rx = jiffies; 1219 1220 /* make sure mandatory rates are always added */ 1221 sband = local->hw.wiphy->bands[band]; 1222 sta->sta.supp_rates[band] = supp_rates | 1223 ieee80211_mandatory_rates(sband, scan_width); 1224 1225 spin_lock(&ifibss->incomplete_lock); 1226 list_add(&sta->list, &ifibss->incomplete_stations); 1227 spin_unlock(&ifibss->incomplete_lock); 1228 ieee80211_queue_work(&local->hw, &sdata->work); 1229 } 1230 1231 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata) 1232 { 1233 struct ieee80211_local *local = sdata->local; 1234 struct sta_info *sta, *tmp; 1235 unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT; 1236 unsigned long exp_rsn_time = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT; 1237 1238 mutex_lock(&local->sta_mtx); 1239 1240 list_for_each_entry_safe(sta, tmp, &local->sta_list, list) { 1241 if (sdata != sta->sdata) 1242 continue; 1243 1244 if (time_after(jiffies, sta->last_rx + exp_time) || 1245 (time_after(jiffies, sta->last_rx + exp_rsn_time) && 1246 sta->sta_state != IEEE80211_STA_AUTHORIZED)) { 1247 sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n", 1248 sta->sta_state != IEEE80211_STA_AUTHORIZED ? 1249 "not authorized " : "", sta->sta.addr); 1250 1251 WARN_ON(__sta_info_destroy(sta)); 1252 } 1253 } 1254 1255 mutex_unlock(&local->sta_mtx); 1256 } 1257 1258 /* 1259 * This function is called with state == IEEE80211_IBSS_MLME_JOINED 1260 */ 1261 1262 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata) 1263 { 1264 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1265 enum nl80211_bss_scan_width scan_width; 1266 1267 sdata_assert_lock(sdata); 1268 1269 mod_timer(&ifibss->timer, 1270 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 1271 1272 ieee80211_ibss_sta_expire(sdata); 1273 1274 if (time_before(jiffies, ifibss->last_scan_completed + 1275 IEEE80211_IBSS_MERGE_INTERVAL)) 1276 return; 1277 1278 if (ieee80211_sta_active_ibss(sdata)) 1279 return; 1280 1281 if (ifibss->fixed_channel) 1282 return; 1283 1284 sdata_info(sdata, 1285 "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n"); 1286 1287 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef); 1288 ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len, 1289 NULL, scan_width); 1290 } 1291 1292 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata) 1293 { 1294 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1295 u8 bssid[ETH_ALEN]; 1296 u16 capability; 1297 int i; 1298 1299 sdata_assert_lock(sdata); 1300 1301 if (ifibss->fixed_bssid) { 1302 memcpy(bssid, ifibss->bssid, ETH_ALEN); 1303 } else { 1304 /* Generate random, not broadcast, locally administered BSSID. Mix in 1305 * own MAC address to make sure that devices that do not have proper 1306 * random number generator get different BSSID. */ 1307 get_random_bytes(bssid, ETH_ALEN); 1308 for (i = 0; i < ETH_ALEN; i++) 1309 bssid[i] ^= sdata->vif.addr[i]; 1310 bssid[0] &= ~0x01; 1311 bssid[0] |= 0x02; 1312 } 1313 1314 sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid); 1315 1316 capability = WLAN_CAPABILITY_IBSS; 1317 1318 if (ifibss->privacy) 1319 capability |= WLAN_CAPABILITY_PRIVACY; 1320 else 1321 sdata->drop_unencrypted = 0; 1322 1323 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int, 1324 &ifibss->chandef, ifibss->basic_rates, 1325 capability, 0, true); 1326 } 1327 1328 /* 1329 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH 1330 */ 1331 1332 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata) 1333 { 1334 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1335 struct ieee80211_local *local = sdata->local; 1336 struct cfg80211_bss *cbss; 1337 struct ieee80211_channel *chan = NULL; 1338 const u8 *bssid = NULL; 1339 enum nl80211_bss_scan_width scan_width; 1340 int active_ibss; 1341 u16 capability; 1342 1343 sdata_assert_lock(sdata); 1344 1345 active_ibss = ieee80211_sta_active_ibss(sdata); 1346 ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss); 1347 1348 if (active_ibss) 1349 return; 1350 1351 capability = WLAN_CAPABILITY_IBSS; 1352 if (ifibss->privacy) 1353 capability |= WLAN_CAPABILITY_PRIVACY; 1354 if (ifibss->fixed_bssid) 1355 bssid = ifibss->bssid; 1356 if (ifibss->fixed_channel) 1357 chan = ifibss->chandef.chan; 1358 if (!is_zero_ether_addr(ifibss->bssid)) 1359 bssid = ifibss->bssid; 1360 cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid, 1361 ifibss->ssid, ifibss->ssid_len, 1362 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY, 1363 capability); 1364 1365 if (cbss) { 1366 struct ieee80211_bss *bss; 1367 1368 bss = (void *)cbss->priv; 1369 ibss_dbg(sdata, 1370 "sta_find_ibss: selected %pM current %pM\n", 1371 cbss->bssid, ifibss->bssid); 1372 sdata_info(sdata, 1373 "Selected IBSS BSSID %pM based on configured SSID\n", 1374 cbss->bssid); 1375 1376 ieee80211_sta_join_ibss(sdata, bss); 1377 ieee80211_rx_bss_put(local, bss); 1378 return; 1379 } 1380 1381 /* if a fixed bssid and a fixed freq have been provided create the IBSS 1382 * directly and do not waste time scanning 1383 */ 1384 if (ifibss->fixed_bssid && ifibss->fixed_channel) { 1385 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n", 1386 bssid); 1387 ieee80211_sta_create_ibss(sdata); 1388 return; 1389 } 1390 1391 1392 ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n"); 1393 1394 /* Selected IBSS not found in current scan results - try to scan */ 1395 if (time_after(jiffies, ifibss->last_scan_completed + 1396 IEEE80211_SCAN_INTERVAL)) { 1397 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n"); 1398 1399 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef); 1400 ieee80211_request_ibss_scan(sdata, ifibss->ssid, 1401 ifibss->ssid_len, chan, 1402 scan_width); 1403 } else { 1404 int interval = IEEE80211_SCAN_INTERVAL; 1405 1406 if (time_after(jiffies, ifibss->ibss_join_req + 1407 IEEE80211_IBSS_JOIN_TIMEOUT)) 1408 ieee80211_sta_create_ibss(sdata); 1409 1410 mod_timer(&ifibss->timer, 1411 round_jiffies(jiffies + interval)); 1412 } 1413 } 1414 1415 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata, 1416 struct sk_buff *req) 1417 { 1418 struct ieee80211_mgmt *mgmt = (void *)req->data; 1419 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1420 struct ieee80211_local *local = sdata->local; 1421 int tx_last_beacon, len = req->len; 1422 struct sk_buff *skb; 1423 struct beacon_data *presp; 1424 u8 *pos, *end; 1425 1426 sdata_assert_lock(sdata); 1427 1428 presp = rcu_dereference_protected(ifibss->presp, 1429 lockdep_is_held(&sdata->wdev.mtx)); 1430 1431 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED || 1432 len < 24 + 2 || !presp) 1433 return; 1434 1435 tx_last_beacon = drv_tx_last_beacon(local); 1436 1437 ibss_dbg(sdata, 1438 "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n", 1439 mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon); 1440 1441 if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da)) 1442 return; 1443 1444 if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) && 1445 !is_broadcast_ether_addr(mgmt->bssid)) 1446 return; 1447 1448 end = ((u8 *) mgmt) + len; 1449 pos = mgmt->u.probe_req.variable; 1450 if (pos[0] != WLAN_EID_SSID || 1451 pos + 2 + pos[1] > end) { 1452 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n", 1453 mgmt->sa); 1454 return; 1455 } 1456 if (pos[1] != 0 && 1457 (pos[1] != ifibss->ssid_len || 1458 memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) { 1459 /* Ignore ProbeReq for foreign SSID */ 1460 return; 1461 } 1462 1463 /* Reply with ProbeResp */ 1464 skb = dev_alloc_skb(local->tx_headroom + presp->head_len); 1465 if (!skb) 1466 return; 1467 1468 skb_reserve(skb, local->tx_headroom); 1469 memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len); 1470 1471 memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN); 1472 ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa); 1473 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 1474 ieee80211_tx_skb(sdata, skb); 1475 } 1476 1477 static 1478 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata, 1479 struct ieee80211_mgmt *mgmt, size_t len, 1480 struct ieee80211_rx_status *rx_status) 1481 { 1482 size_t baselen; 1483 struct ieee802_11_elems elems; 1484 1485 BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) != 1486 offsetof(typeof(mgmt->u.beacon), variable)); 1487 1488 /* 1489 * either beacon or probe_resp but the variable field is at the 1490 * same offset 1491 */ 1492 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt; 1493 if (baselen > len) 1494 return; 1495 1496 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen, 1497 false, &elems); 1498 1499 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems); 1500 } 1501 1502 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata, 1503 struct sk_buff *skb) 1504 { 1505 struct ieee80211_rx_status *rx_status; 1506 struct ieee80211_mgmt *mgmt; 1507 u16 fc; 1508 struct ieee802_11_elems elems; 1509 int ies_len; 1510 1511 rx_status = IEEE80211_SKB_RXCB(skb); 1512 mgmt = (struct ieee80211_mgmt *) skb->data; 1513 fc = le16_to_cpu(mgmt->frame_control); 1514 1515 sdata_lock(sdata); 1516 1517 if (!sdata->u.ibss.ssid_len) 1518 goto mgmt_out; /* not ready to merge yet */ 1519 1520 switch (fc & IEEE80211_FCTL_STYPE) { 1521 case IEEE80211_STYPE_PROBE_REQ: 1522 ieee80211_rx_mgmt_probe_req(sdata, skb); 1523 break; 1524 case IEEE80211_STYPE_PROBE_RESP: 1525 case IEEE80211_STYPE_BEACON: 1526 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len, 1527 rx_status); 1528 break; 1529 case IEEE80211_STYPE_AUTH: 1530 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len); 1531 break; 1532 case IEEE80211_STYPE_DEAUTH: 1533 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len); 1534 break; 1535 case IEEE80211_STYPE_ACTION: 1536 switch (mgmt->u.action.category) { 1537 case WLAN_CATEGORY_SPECTRUM_MGMT: 1538 ies_len = skb->len - 1539 offsetof(struct ieee80211_mgmt, 1540 u.action.u.chan_switch.variable); 1541 1542 if (ies_len < 0) 1543 break; 1544 1545 ieee802_11_parse_elems( 1546 mgmt->u.action.u.chan_switch.variable, 1547 ies_len, true, &elems); 1548 1549 if (elems.parse_error) 1550 break; 1551 1552 ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len, 1553 rx_status, &elems); 1554 break; 1555 } 1556 } 1557 1558 mgmt_out: 1559 sdata_unlock(sdata); 1560 } 1561 1562 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata) 1563 { 1564 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1565 struct sta_info *sta; 1566 1567 sdata_lock(sdata); 1568 1569 /* 1570 * Work could be scheduled after scan or similar 1571 * when we aren't even joined (or trying) with a 1572 * network. 1573 */ 1574 if (!ifibss->ssid_len) 1575 goto out; 1576 1577 spin_lock_bh(&ifibss->incomplete_lock); 1578 while (!list_empty(&ifibss->incomplete_stations)) { 1579 sta = list_first_entry(&ifibss->incomplete_stations, 1580 struct sta_info, list); 1581 list_del(&sta->list); 1582 spin_unlock_bh(&ifibss->incomplete_lock); 1583 1584 ieee80211_ibss_finish_sta(sta); 1585 rcu_read_unlock(); 1586 spin_lock_bh(&ifibss->incomplete_lock); 1587 } 1588 spin_unlock_bh(&ifibss->incomplete_lock); 1589 1590 switch (ifibss->state) { 1591 case IEEE80211_IBSS_MLME_SEARCH: 1592 ieee80211_sta_find_ibss(sdata); 1593 break; 1594 case IEEE80211_IBSS_MLME_JOINED: 1595 ieee80211_sta_merge_ibss(sdata); 1596 break; 1597 default: 1598 WARN_ON(1); 1599 break; 1600 } 1601 1602 out: 1603 sdata_unlock(sdata); 1604 } 1605 1606 static void ieee80211_ibss_timer(unsigned long data) 1607 { 1608 struct ieee80211_sub_if_data *sdata = 1609 (struct ieee80211_sub_if_data *) data; 1610 1611 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 1612 } 1613 1614 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata) 1615 { 1616 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1617 1618 setup_timer(&ifibss->timer, ieee80211_ibss_timer, 1619 (unsigned long) sdata); 1620 INIT_LIST_HEAD(&ifibss->incomplete_stations); 1621 spin_lock_init(&ifibss->incomplete_lock); 1622 INIT_WORK(&ifibss->csa_connection_drop_work, 1623 ieee80211_csa_connection_drop_work); 1624 } 1625 1626 /* scan finished notification */ 1627 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local) 1628 { 1629 struct ieee80211_sub_if_data *sdata; 1630 1631 mutex_lock(&local->iflist_mtx); 1632 list_for_each_entry(sdata, &local->interfaces, list) { 1633 if (!ieee80211_sdata_running(sdata)) 1634 continue; 1635 if (sdata->vif.type != NL80211_IFTYPE_ADHOC) 1636 continue; 1637 sdata->u.ibss.last_scan_completed = jiffies; 1638 ieee80211_queue_work(&local->hw, &sdata->work); 1639 } 1640 mutex_unlock(&local->iflist_mtx); 1641 } 1642 1643 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata, 1644 struct cfg80211_ibss_params *params) 1645 { 1646 u32 changed = 0; 1647 u32 rate_flags; 1648 struct ieee80211_supported_band *sband; 1649 int i; 1650 1651 if (params->bssid) { 1652 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN); 1653 sdata->u.ibss.fixed_bssid = true; 1654 } else 1655 sdata->u.ibss.fixed_bssid = false; 1656 1657 sdata->u.ibss.privacy = params->privacy; 1658 sdata->u.ibss.control_port = params->control_port; 1659 sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs; 1660 sdata->u.ibss.basic_rates = params->basic_rates; 1661 1662 /* fix basic_rates if channel does not support these rates */ 1663 rate_flags = ieee80211_chandef_rate_flags(¶ms->chandef); 1664 sband = sdata->local->hw.wiphy->bands[params->chandef.chan->band]; 1665 for (i = 0; i < sband->n_bitrates; i++) { 1666 if ((rate_flags & sband->bitrates[i].flags) != rate_flags) 1667 sdata->u.ibss.basic_rates &= ~BIT(i); 1668 } 1669 memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate, 1670 sizeof(params->mcast_rate)); 1671 1672 sdata->vif.bss_conf.beacon_int = params->beacon_interval; 1673 1674 sdata->u.ibss.chandef = params->chandef; 1675 sdata->u.ibss.fixed_channel = params->channel_fixed; 1676 1677 if (params->ie) { 1678 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len, 1679 GFP_KERNEL); 1680 if (sdata->u.ibss.ie) 1681 sdata->u.ibss.ie_len = params->ie_len; 1682 } 1683 1684 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; 1685 sdata->u.ibss.ibss_join_req = jiffies; 1686 1687 memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len); 1688 sdata->u.ibss.ssid_len = params->ssid_len; 1689 1690 memcpy(&sdata->u.ibss.ht_capa, ¶ms->ht_capa, 1691 sizeof(sdata->u.ibss.ht_capa)); 1692 memcpy(&sdata->u.ibss.ht_capa_mask, ¶ms->ht_capa_mask, 1693 sizeof(sdata->u.ibss.ht_capa_mask)); 1694 1695 /* 1696 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is 1697 * reserved, but an HT STA shall protect HT transmissions as though 1698 * the HT Protection field were set to non-HT mixed mode. 1699 * 1700 * In an IBSS, the RIFS Mode field of the HT Operation element is 1701 * also reserved, but an HT STA shall operate as though this field 1702 * were set to 1. 1703 */ 1704 1705 sdata->vif.bss_conf.ht_operation_mode |= 1706 IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED 1707 | IEEE80211_HT_PARAM_RIFS_MODE; 1708 1709 changed |= BSS_CHANGED_HT; 1710 ieee80211_bss_info_change_notify(sdata, changed); 1711 1712 sdata->smps_mode = IEEE80211_SMPS_OFF; 1713 sdata->needed_rx_chains = sdata->local->rx_chains; 1714 1715 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 1716 1717 return 0; 1718 } 1719 1720 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata) 1721 { 1722 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1723 1724 ieee80211_ibss_disconnect(sdata); 1725 ifibss->ssid_len = 0; 1726 memset(ifibss->bssid, 0, ETH_ALEN); 1727 1728 /* remove beacon */ 1729 kfree(sdata->u.ibss.ie); 1730 1731 /* on the next join, re-program HT parameters */ 1732 memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa)); 1733 memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask)); 1734 1735 synchronize_rcu(); 1736 1737 skb_queue_purge(&sdata->skb_queue); 1738 1739 del_timer_sync(&sdata->u.ibss.timer); 1740 1741 return 0; 1742 } 1743