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 u16 capability; 699 700 if (!is_zero_ether_addr(ifibss->bssid)) { 701 capability = WLAN_CAPABILITY_IBSS; 702 703 if (ifibss->privacy) 704 capability |= WLAN_CAPABILITY_PRIVACY; 705 706 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan, 707 ifibss->bssid, ifibss->ssid, 708 ifibss->ssid_len, WLAN_CAPABILITY_IBSS | 709 WLAN_CAPABILITY_PRIVACY, 710 capability); 711 712 if (cbss) { 713 cfg80211_unlink_bss(local->hw.wiphy, cbss); 714 cfg80211_put_bss(sdata->local->hw.wiphy, cbss); 715 } 716 } 717 718 ifibss->state = IEEE80211_IBSS_MLME_SEARCH; 719 720 sta_info_flush(sdata); 721 722 spin_lock_bh(&ifibss->incomplete_lock); 723 while (!list_empty(&ifibss->incomplete_stations)) { 724 sta = list_first_entry(&ifibss->incomplete_stations, 725 struct sta_info, list); 726 list_del(&sta->list); 727 spin_unlock_bh(&ifibss->incomplete_lock); 728 729 sta_info_free(local, sta); 730 spin_lock_bh(&ifibss->incomplete_lock); 731 } 732 spin_unlock_bh(&ifibss->incomplete_lock); 733 734 netif_carrier_off(sdata->dev); 735 736 sdata->vif.bss_conf.ibss_joined = false; 737 sdata->vif.bss_conf.ibss_creator = false; 738 sdata->vif.bss_conf.enable_beacon = false; 739 sdata->vif.bss_conf.ssid_len = 0; 740 741 /* remove beacon */ 742 presp = rcu_dereference_protected(ifibss->presp, 743 lockdep_is_held(&sdata->wdev.mtx)); 744 RCU_INIT_POINTER(sdata->u.ibss.presp, NULL); 745 if (presp) 746 kfree_rcu(presp, rcu_head); 747 748 clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state); 749 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED | 750 BSS_CHANGED_IBSS); 751 drv_leave_ibss(local, sdata); 752 mutex_lock(&local->mtx); 753 ieee80211_vif_release_channel(sdata); 754 mutex_unlock(&local->mtx); 755 } 756 757 static void ieee80211_csa_connection_drop_work(struct work_struct *work) 758 { 759 struct ieee80211_sub_if_data *sdata = 760 container_of(work, struct ieee80211_sub_if_data, 761 u.ibss.csa_connection_drop_work); 762 763 sdata_lock(sdata); 764 765 ieee80211_ibss_disconnect(sdata); 766 synchronize_rcu(); 767 skb_queue_purge(&sdata->skb_queue); 768 769 /* trigger a scan to find another IBSS network to join */ 770 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 771 772 sdata_unlock(sdata); 773 } 774 775 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata) 776 { 777 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 778 int err; 779 780 /* if the current channel is a DFS channel, mark the channel as 781 * unavailable. 782 */ 783 err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy, 784 &ifibss->chandef); 785 if (err > 0) 786 cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef, 787 GFP_ATOMIC); 788 } 789 790 static bool 791 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata, 792 struct ieee802_11_elems *elems, 793 bool beacon) 794 { 795 struct cfg80211_csa_settings params; 796 struct ieee80211_csa_ie csa_ie; 797 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 798 enum nl80211_channel_type ch_type; 799 int err; 800 u32 sta_flags; 801 802 sta_flags = IEEE80211_STA_DISABLE_VHT; 803 switch (ifibss->chandef.width) { 804 case NL80211_CHAN_WIDTH_5: 805 case NL80211_CHAN_WIDTH_10: 806 case NL80211_CHAN_WIDTH_20_NOHT: 807 sta_flags |= IEEE80211_STA_DISABLE_HT; 808 /* fall through */ 809 case NL80211_CHAN_WIDTH_20: 810 sta_flags |= IEEE80211_STA_DISABLE_40MHZ; 811 break; 812 default: 813 break; 814 } 815 816 memset(¶ms, 0, sizeof(params)); 817 memset(&csa_ie, 0, sizeof(csa_ie)); 818 err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon, 819 ifibss->chandef.chan->band, 820 sta_flags, ifibss->bssid, &csa_ie); 821 /* can't switch to destination channel, fail */ 822 if (err < 0) 823 goto disconnect; 824 825 /* did not contain a CSA */ 826 if (err) 827 return false; 828 829 /* channel switch is not supported, disconnect */ 830 if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH)) 831 goto disconnect; 832 833 params.count = csa_ie.count; 834 params.chandef = csa_ie.chandef; 835 836 switch (ifibss->chandef.width) { 837 case NL80211_CHAN_WIDTH_20_NOHT: 838 case NL80211_CHAN_WIDTH_20: 839 case NL80211_CHAN_WIDTH_40: 840 /* keep our current HT mode (HT20/HT40+/HT40-), even if 841 * another mode has been announced. The mode is not adopted 842 * within the beacon while doing CSA and we should therefore 843 * keep the mode which we announce. 844 */ 845 ch_type = cfg80211_get_chandef_type(&ifibss->chandef); 846 cfg80211_chandef_create(¶ms.chandef, params.chandef.chan, 847 ch_type); 848 break; 849 case NL80211_CHAN_WIDTH_5: 850 case NL80211_CHAN_WIDTH_10: 851 if (params.chandef.width != ifibss->chandef.width) { 852 sdata_info(sdata, 853 "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n", 854 ifibss->bssid, 855 params.chandef.chan->center_freq, 856 params.chandef.width, 857 params.chandef.center_freq1, 858 params.chandef.center_freq2); 859 goto disconnect; 860 } 861 break; 862 default: 863 /* should not happen, sta_flags should prevent VHT modes. */ 864 WARN_ON(1); 865 goto disconnect; 866 } 867 868 if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, ¶ms.chandef)) { 869 sdata_info(sdata, 870 "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n", 871 ifibss->bssid, 872 params.chandef.chan->center_freq, 873 params.chandef.width, 874 params.chandef.center_freq1, 875 params.chandef.center_freq2); 876 goto disconnect; 877 } 878 879 err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy, 880 ¶ms.chandef); 881 if (err < 0) 882 goto disconnect; 883 if (err) { 884 /* IBSS-DFS only allowed with a control program */ 885 if (!ifibss->userspace_handles_dfs) 886 goto disconnect; 887 888 params.radar_required = true; 889 } 890 891 if (cfg80211_chandef_identical(¶ms.chandef, 892 &sdata->vif.bss_conf.chandef)) { 893 ibss_dbg(sdata, 894 "received csa with an identical chandef, ignoring\n"); 895 return true; 896 } 897 898 /* all checks done, now perform the channel switch. */ 899 ibss_dbg(sdata, 900 "received channel switch announcement to go to channel %d MHz\n", 901 params.chandef.chan->center_freq); 902 903 params.block_tx = !!csa_ie.mode; 904 905 if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev, 906 ¶ms)) 907 goto disconnect; 908 909 ieee80211_ibss_csa_mark_radar(sdata); 910 911 return true; 912 disconnect: 913 ibss_dbg(sdata, "Can't handle channel switch, disconnect\n"); 914 ieee80211_queue_work(&sdata->local->hw, 915 &ifibss->csa_connection_drop_work); 916 917 ieee80211_ibss_csa_mark_radar(sdata); 918 919 return true; 920 } 921 922 static void 923 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata, 924 struct ieee80211_mgmt *mgmt, size_t len, 925 struct ieee80211_rx_status *rx_status, 926 struct ieee802_11_elems *elems) 927 { 928 int required_len; 929 930 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 931 return; 932 933 /* CSA is the only action we handle for now */ 934 if (mgmt->u.action.u.measurement.action_code != 935 WLAN_ACTION_SPCT_CHL_SWITCH) 936 return; 937 938 required_len = IEEE80211_MIN_ACTION_SIZE + 939 sizeof(mgmt->u.action.u.chan_switch); 940 if (len < required_len) 941 return; 942 943 if (!sdata->vif.csa_active) 944 ieee80211_ibss_process_chanswitch(sdata, elems, false); 945 } 946 947 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata, 948 struct ieee80211_mgmt *mgmt, 949 size_t len) 950 { 951 u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code); 952 953 if (len < IEEE80211_DEAUTH_FRAME_LEN) 954 return; 955 956 ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n", 957 mgmt->sa, mgmt->da, mgmt->bssid, reason); 958 sta_info_destroy_addr(sdata, mgmt->sa); 959 } 960 961 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata, 962 struct ieee80211_mgmt *mgmt, 963 size_t len) 964 { 965 u16 auth_alg, auth_transaction; 966 967 sdata_assert_lock(sdata); 968 969 if (len < 24 + 6) 970 return; 971 972 auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg); 973 auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction); 974 975 ibss_dbg(sdata, 976 "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n", 977 mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction); 978 979 if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1) 980 return; 981 982 /* 983 * IEEE 802.11 standard does not require authentication in IBSS 984 * networks and most implementations do not seem to use it. 985 * However, try to reply to authentication attempts if someone 986 * has actually implemented this. 987 */ 988 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0, 989 mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0); 990 } 991 992 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, 993 struct ieee80211_mgmt *mgmt, size_t len, 994 struct ieee80211_rx_status *rx_status, 995 struct ieee802_11_elems *elems) 996 { 997 struct ieee80211_local *local = sdata->local; 998 int freq; 999 struct cfg80211_bss *cbss; 1000 struct ieee80211_bss *bss; 1001 struct sta_info *sta; 1002 struct ieee80211_channel *channel; 1003 u64 beacon_timestamp, rx_timestamp; 1004 u32 supp_rates = 0; 1005 enum ieee80211_band band = rx_status->band; 1006 enum nl80211_bss_scan_width scan_width; 1007 struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band]; 1008 bool rates_updated = false; 1009 1010 if (elems->ds_params) 1011 freq = ieee80211_channel_to_frequency(elems->ds_params[0], 1012 band); 1013 else 1014 freq = rx_status->freq; 1015 1016 channel = ieee80211_get_channel(local->hw.wiphy, freq); 1017 1018 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 1019 return; 1020 1021 if (sdata->vif.type == NL80211_IFTYPE_ADHOC && 1022 ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) { 1023 1024 rcu_read_lock(); 1025 sta = sta_info_get(sdata, mgmt->sa); 1026 1027 if (elems->supp_rates) { 1028 supp_rates = ieee80211_sta_get_rates(sdata, elems, 1029 band, NULL); 1030 if (sta) { 1031 u32 prev_rates; 1032 1033 prev_rates = sta->sta.supp_rates[band]; 1034 /* make sure mandatory rates are always added */ 1035 scan_width = NL80211_BSS_CHAN_WIDTH_20; 1036 if (rx_status->flag & RX_FLAG_5MHZ) 1037 scan_width = NL80211_BSS_CHAN_WIDTH_5; 1038 if (rx_status->flag & RX_FLAG_10MHZ) 1039 scan_width = NL80211_BSS_CHAN_WIDTH_10; 1040 1041 sta->sta.supp_rates[band] = supp_rates | 1042 ieee80211_mandatory_rates(sband, 1043 scan_width); 1044 if (sta->sta.supp_rates[band] != prev_rates) { 1045 ibss_dbg(sdata, 1046 "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n", 1047 sta->sta.addr, prev_rates, 1048 sta->sta.supp_rates[band]); 1049 rates_updated = true; 1050 } 1051 } else { 1052 rcu_read_unlock(); 1053 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, 1054 mgmt->sa, supp_rates); 1055 } 1056 } 1057 1058 if (sta && elems->wmm_info) 1059 set_sta_flag(sta, WLAN_STA_WME); 1060 1061 if (sta && elems->ht_operation && elems->ht_cap_elem && 1062 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT && 1063 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 && 1064 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) { 1065 /* we both use HT */ 1066 struct ieee80211_ht_cap htcap_ie; 1067 struct cfg80211_chan_def chandef; 1068 1069 ieee80211_ht_oper_to_chandef(channel, 1070 elems->ht_operation, 1071 &chandef); 1072 1073 memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie)); 1074 1075 /* 1076 * fall back to HT20 if we don't use or use 1077 * the other extension channel 1078 */ 1079 if (chandef.center_freq1 != 1080 sdata->u.ibss.chandef.center_freq1) 1081 htcap_ie.cap_info &= 1082 cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40); 1083 1084 rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap( 1085 sdata, sband, &htcap_ie, sta); 1086 } 1087 1088 if (sta && rates_updated) { 1089 drv_sta_rc_update(local, sdata, &sta->sta, 1090 IEEE80211_RC_SUPP_RATES_CHANGED); 1091 rate_control_rate_init(sta); 1092 } 1093 1094 rcu_read_unlock(); 1095 } 1096 1097 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems, 1098 channel); 1099 if (!bss) 1100 return; 1101 1102 cbss = container_of((void *)bss, struct cfg80211_bss, priv); 1103 1104 /* same for beacon and probe response */ 1105 beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp); 1106 1107 /* check if we need to merge IBSS */ 1108 1109 /* not an IBSS */ 1110 if (!(cbss->capability & WLAN_CAPABILITY_IBSS)) 1111 goto put_bss; 1112 1113 /* different channel */ 1114 if (sdata->u.ibss.fixed_channel && 1115 sdata->u.ibss.chandef.chan != cbss->channel) 1116 goto put_bss; 1117 1118 /* different SSID */ 1119 if (elems->ssid_len != sdata->u.ibss.ssid_len || 1120 memcmp(elems->ssid, sdata->u.ibss.ssid, 1121 sdata->u.ibss.ssid_len)) 1122 goto put_bss; 1123 1124 /* process channel switch */ 1125 if (sdata->vif.csa_active || 1126 ieee80211_ibss_process_chanswitch(sdata, elems, true)) 1127 goto put_bss; 1128 1129 /* same BSSID */ 1130 if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid)) 1131 goto put_bss; 1132 1133 /* we use a fixed BSSID */ 1134 if (sdata->u.ibss.fixed_bssid) 1135 goto put_bss; 1136 1137 if (ieee80211_have_rx_timestamp(rx_status)) { 1138 /* time when timestamp field was received */ 1139 rx_timestamp = 1140 ieee80211_calculate_rx_timestamp(local, rx_status, 1141 len + FCS_LEN, 24); 1142 } else { 1143 /* 1144 * second best option: get current TSF 1145 * (will return -1 if not supported) 1146 */ 1147 rx_timestamp = drv_get_tsf(local, sdata); 1148 } 1149 1150 ibss_dbg(sdata, 1151 "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n", 1152 mgmt->sa, mgmt->bssid, 1153 (unsigned long long)rx_timestamp, 1154 (unsigned long long)beacon_timestamp, 1155 (unsigned long long)(rx_timestamp - beacon_timestamp), 1156 jiffies); 1157 1158 if (beacon_timestamp > rx_timestamp) { 1159 ibss_dbg(sdata, 1160 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n", 1161 mgmt->bssid); 1162 ieee80211_sta_join_ibss(sdata, bss); 1163 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL); 1164 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 1165 supp_rates); 1166 rcu_read_unlock(); 1167 } 1168 1169 put_bss: 1170 ieee80211_rx_bss_put(local, bss); 1171 } 1172 1173 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata, 1174 const u8 *bssid, const u8 *addr, 1175 u32 supp_rates) 1176 { 1177 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1178 struct ieee80211_local *local = sdata->local; 1179 struct sta_info *sta; 1180 struct ieee80211_chanctx_conf *chanctx_conf; 1181 struct ieee80211_supported_band *sband; 1182 enum nl80211_bss_scan_width scan_width; 1183 int band; 1184 1185 /* 1186 * XXX: Consider removing the least recently used entry and 1187 * allow new one to be added. 1188 */ 1189 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 1190 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n", 1191 sdata->name, addr); 1192 return; 1193 } 1194 1195 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) 1196 return; 1197 1198 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) 1199 return; 1200 1201 rcu_read_lock(); 1202 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); 1203 if (WARN_ON_ONCE(!chanctx_conf)) { 1204 rcu_read_unlock(); 1205 return; 1206 } 1207 band = chanctx_conf->def.chan->band; 1208 scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def); 1209 rcu_read_unlock(); 1210 1211 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC); 1212 if (!sta) 1213 return; 1214 1215 sta->last_rx = jiffies; 1216 1217 /* make sure mandatory rates are always added */ 1218 sband = local->hw.wiphy->bands[band]; 1219 sta->sta.supp_rates[band] = supp_rates | 1220 ieee80211_mandatory_rates(sband, scan_width); 1221 1222 spin_lock(&ifibss->incomplete_lock); 1223 list_add(&sta->list, &ifibss->incomplete_stations); 1224 spin_unlock(&ifibss->incomplete_lock); 1225 ieee80211_queue_work(&local->hw, &sdata->work); 1226 } 1227 1228 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata) 1229 { 1230 struct ieee80211_local *local = sdata->local; 1231 struct sta_info *sta, *tmp; 1232 unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT; 1233 unsigned long exp_rsn_time = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT; 1234 1235 mutex_lock(&local->sta_mtx); 1236 1237 list_for_each_entry_safe(sta, tmp, &local->sta_list, list) { 1238 if (sdata != sta->sdata) 1239 continue; 1240 1241 if (time_after(jiffies, sta->last_rx + exp_time) || 1242 (time_after(jiffies, sta->last_rx + exp_rsn_time) && 1243 sta->sta_state != IEEE80211_STA_AUTHORIZED)) { 1244 sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n", 1245 sta->sta_state != IEEE80211_STA_AUTHORIZED ? 1246 "not authorized " : "", sta->sta.addr); 1247 1248 WARN_ON(__sta_info_destroy(sta)); 1249 } 1250 } 1251 1252 mutex_unlock(&local->sta_mtx); 1253 } 1254 1255 /* 1256 * This function is called with state == IEEE80211_IBSS_MLME_JOINED 1257 */ 1258 1259 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata) 1260 { 1261 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1262 enum nl80211_bss_scan_width scan_width; 1263 1264 sdata_assert_lock(sdata); 1265 1266 mod_timer(&ifibss->timer, 1267 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 1268 1269 ieee80211_ibss_sta_expire(sdata); 1270 1271 if (time_before(jiffies, ifibss->last_scan_completed + 1272 IEEE80211_IBSS_MERGE_INTERVAL)) 1273 return; 1274 1275 if (ieee80211_sta_active_ibss(sdata)) 1276 return; 1277 1278 if (ifibss->fixed_channel) 1279 return; 1280 1281 sdata_info(sdata, 1282 "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n"); 1283 1284 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef); 1285 ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len, 1286 NULL, scan_width); 1287 } 1288 1289 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata) 1290 { 1291 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1292 u8 bssid[ETH_ALEN]; 1293 u16 capability; 1294 int i; 1295 1296 sdata_assert_lock(sdata); 1297 1298 if (ifibss->fixed_bssid) { 1299 memcpy(bssid, ifibss->bssid, ETH_ALEN); 1300 } else { 1301 /* Generate random, not broadcast, locally administered BSSID. Mix in 1302 * own MAC address to make sure that devices that do not have proper 1303 * random number generator get different BSSID. */ 1304 get_random_bytes(bssid, ETH_ALEN); 1305 for (i = 0; i < ETH_ALEN; i++) 1306 bssid[i] ^= sdata->vif.addr[i]; 1307 bssid[0] &= ~0x01; 1308 bssid[0] |= 0x02; 1309 } 1310 1311 sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid); 1312 1313 capability = WLAN_CAPABILITY_IBSS; 1314 1315 if (ifibss->privacy) 1316 capability |= WLAN_CAPABILITY_PRIVACY; 1317 else 1318 sdata->drop_unencrypted = 0; 1319 1320 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int, 1321 &ifibss->chandef, ifibss->basic_rates, 1322 capability, 0, true); 1323 } 1324 1325 /* 1326 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH 1327 */ 1328 1329 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata) 1330 { 1331 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1332 struct ieee80211_local *local = sdata->local; 1333 struct cfg80211_bss *cbss; 1334 struct ieee80211_channel *chan = NULL; 1335 const u8 *bssid = NULL; 1336 enum nl80211_bss_scan_width scan_width; 1337 int active_ibss; 1338 u16 capability; 1339 1340 sdata_assert_lock(sdata); 1341 1342 active_ibss = ieee80211_sta_active_ibss(sdata); 1343 ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss); 1344 1345 if (active_ibss) 1346 return; 1347 1348 capability = WLAN_CAPABILITY_IBSS; 1349 if (ifibss->privacy) 1350 capability |= WLAN_CAPABILITY_PRIVACY; 1351 if (ifibss->fixed_bssid) 1352 bssid = ifibss->bssid; 1353 if (ifibss->fixed_channel) 1354 chan = ifibss->chandef.chan; 1355 if (!is_zero_ether_addr(ifibss->bssid)) 1356 bssid = ifibss->bssid; 1357 cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid, 1358 ifibss->ssid, ifibss->ssid_len, 1359 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY, 1360 capability); 1361 1362 if (cbss) { 1363 struct ieee80211_bss *bss; 1364 1365 bss = (void *)cbss->priv; 1366 ibss_dbg(sdata, 1367 "sta_find_ibss: selected %pM current %pM\n", 1368 cbss->bssid, ifibss->bssid); 1369 sdata_info(sdata, 1370 "Selected IBSS BSSID %pM based on configured SSID\n", 1371 cbss->bssid); 1372 1373 ieee80211_sta_join_ibss(sdata, bss); 1374 ieee80211_rx_bss_put(local, bss); 1375 return; 1376 } 1377 1378 /* if a fixed bssid and a fixed freq have been provided create the IBSS 1379 * directly and do not waste time scanning 1380 */ 1381 if (ifibss->fixed_bssid && ifibss->fixed_channel) { 1382 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n", 1383 bssid); 1384 ieee80211_sta_create_ibss(sdata); 1385 return; 1386 } 1387 1388 1389 ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n"); 1390 1391 /* Selected IBSS not found in current scan results - try to scan */ 1392 if (time_after(jiffies, ifibss->last_scan_completed + 1393 IEEE80211_SCAN_INTERVAL)) { 1394 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n"); 1395 1396 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef); 1397 ieee80211_request_ibss_scan(sdata, ifibss->ssid, 1398 ifibss->ssid_len, chan, 1399 scan_width); 1400 } else { 1401 int interval = IEEE80211_SCAN_INTERVAL; 1402 1403 if (time_after(jiffies, ifibss->ibss_join_req + 1404 IEEE80211_IBSS_JOIN_TIMEOUT)) 1405 ieee80211_sta_create_ibss(sdata); 1406 1407 mod_timer(&ifibss->timer, 1408 round_jiffies(jiffies + interval)); 1409 } 1410 } 1411 1412 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata, 1413 struct sk_buff *req) 1414 { 1415 struct ieee80211_mgmt *mgmt = (void *)req->data; 1416 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1417 struct ieee80211_local *local = sdata->local; 1418 int tx_last_beacon, len = req->len; 1419 struct sk_buff *skb; 1420 struct beacon_data *presp; 1421 u8 *pos, *end; 1422 1423 sdata_assert_lock(sdata); 1424 1425 presp = rcu_dereference_protected(ifibss->presp, 1426 lockdep_is_held(&sdata->wdev.mtx)); 1427 1428 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED || 1429 len < 24 + 2 || !presp) 1430 return; 1431 1432 tx_last_beacon = drv_tx_last_beacon(local); 1433 1434 ibss_dbg(sdata, 1435 "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n", 1436 mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon); 1437 1438 if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da)) 1439 return; 1440 1441 if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) && 1442 !is_broadcast_ether_addr(mgmt->bssid)) 1443 return; 1444 1445 end = ((u8 *) mgmt) + len; 1446 pos = mgmt->u.probe_req.variable; 1447 if (pos[0] != WLAN_EID_SSID || 1448 pos + 2 + pos[1] > end) { 1449 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n", 1450 mgmt->sa); 1451 return; 1452 } 1453 if (pos[1] != 0 && 1454 (pos[1] != ifibss->ssid_len || 1455 memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) { 1456 /* Ignore ProbeReq for foreign SSID */ 1457 return; 1458 } 1459 1460 /* Reply with ProbeResp */ 1461 skb = dev_alloc_skb(local->tx_headroom + presp->head_len); 1462 if (!skb) 1463 return; 1464 1465 skb_reserve(skb, local->tx_headroom); 1466 memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len); 1467 1468 memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN); 1469 ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa); 1470 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 1471 ieee80211_tx_skb(sdata, skb); 1472 } 1473 1474 static 1475 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata, 1476 struct ieee80211_mgmt *mgmt, size_t len, 1477 struct ieee80211_rx_status *rx_status) 1478 { 1479 size_t baselen; 1480 struct ieee802_11_elems elems; 1481 1482 BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) != 1483 offsetof(typeof(mgmt->u.beacon), variable)); 1484 1485 /* 1486 * either beacon or probe_resp but the variable field is at the 1487 * same offset 1488 */ 1489 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt; 1490 if (baselen > len) 1491 return; 1492 1493 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen, 1494 false, &elems); 1495 1496 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems); 1497 } 1498 1499 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata, 1500 struct sk_buff *skb) 1501 { 1502 struct ieee80211_rx_status *rx_status; 1503 struct ieee80211_mgmt *mgmt; 1504 u16 fc; 1505 struct ieee802_11_elems elems; 1506 int ies_len; 1507 1508 rx_status = IEEE80211_SKB_RXCB(skb); 1509 mgmt = (struct ieee80211_mgmt *) skb->data; 1510 fc = le16_to_cpu(mgmt->frame_control); 1511 1512 sdata_lock(sdata); 1513 1514 if (!sdata->u.ibss.ssid_len) 1515 goto mgmt_out; /* not ready to merge yet */ 1516 1517 switch (fc & IEEE80211_FCTL_STYPE) { 1518 case IEEE80211_STYPE_PROBE_REQ: 1519 ieee80211_rx_mgmt_probe_req(sdata, skb); 1520 break; 1521 case IEEE80211_STYPE_PROBE_RESP: 1522 case IEEE80211_STYPE_BEACON: 1523 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len, 1524 rx_status); 1525 break; 1526 case IEEE80211_STYPE_AUTH: 1527 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len); 1528 break; 1529 case IEEE80211_STYPE_DEAUTH: 1530 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len); 1531 break; 1532 case IEEE80211_STYPE_ACTION: 1533 switch (mgmt->u.action.category) { 1534 case WLAN_CATEGORY_SPECTRUM_MGMT: 1535 ies_len = skb->len - 1536 offsetof(struct ieee80211_mgmt, 1537 u.action.u.chan_switch.variable); 1538 1539 if (ies_len < 0) 1540 break; 1541 1542 ieee802_11_parse_elems( 1543 mgmt->u.action.u.chan_switch.variable, 1544 ies_len, true, &elems); 1545 1546 if (elems.parse_error) 1547 break; 1548 1549 ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len, 1550 rx_status, &elems); 1551 break; 1552 } 1553 } 1554 1555 mgmt_out: 1556 sdata_unlock(sdata); 1557 } 1558 1559 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata) 1560 { 1561 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1562 struct sta_info *sta; 1563 1564 sdata_lock(sdata); 1565 1566 /* 1567 * Work could be scheduled after scan or similar 1568 * when we aren't even joined (or trying) with a 1569 * network. 1570 */ 1571 if (!ifibss->ssid_len) 1572 goto out; 1573 1574 spin_lock_bh(&ifibss->incomplete_lock); 1575 while (!list_empty(&ifibss->incomplete_stations)) { 1576 sta = list_first_entry(&ifibss->incomplete_stations, 1577 struct sta_info, list); 1578 list_del(&sta->list); 1579 spin_unlock_bh(&ifibss->incomplete_lock); 1580 1581 ieee80211_ibss_finish_sta(sta); 1582 rcu_read_unlock(); 1583 spin_lock_bh(&ifibss->incomplete_lock); 1584 } 1585 spin_unlock_bh(&ifibss->incomplete_lock); 1586 1587 switch (ifibss->state) { 1588 case IEEE80211_IBSS_MLME_SEARCH: 1589 ieee80211_sta_find_ibss(sdata); 1590 break; 1591 case IEEE80211_IBSS_MLME_JOINED: 1592 ieee80211_sta_merge_ibss(sdata); 1593 break; 1594 default: 1595 WARN_ON(1); 1596 break; 1597 } 1598 1599 out: 1600 sdata_unlock(sdata); 1601 } 1602 1603 static void ieee80211_ibss_timer(unsigned long data) 1604 { 1605 struct ieee80211_sub_if_data *sdata = 1606 (struct ieee80211_sub_if_data *) data; 1607 1608 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 1609 } 1610 1611 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata) 1612 { 1613 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1614 1615 setup_timer(&ifibss->timer, ieee80211_ibss_timer, 1616 (unsigned long) sdata); 1617 INIT_LIST_HEAD(&ifibss->incomplete_stations); 1618 spin_lock_init(&ifibss->incomplete_lock); 1619 INIT_WORK(&ifibss->csa_connection_drop_work, 1620 ieee80211_csa_connection_drop_work); 1621 } 1622 1623 /* scan finished notification */ 1624 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local) 1625 { 1626 struct ieee80211_sub_if_data *sdata; 1627 1628 mutex_lock(&local->iflist_mtx); 1629 list_for_each_entry(sdata, &local->interfaces, list) { 1630 if (!ieee80211_sdata_running(sdata)) 1631 continue; 1632 if (sdata->vif.type != NL80211_IFTYPE_ADHOC) 1633 continue; 1634 sdata->u.ibss.last_scan_completed = jiffies; 1635 ieee80211_queue_work(&local->hw, &sdata->work); 1636 } 1637 mutex_unlock(&local->iflist_mtx); 1638 } 1639 1640 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata, 1641 struct cfg80211_ibss_params *params) 1642 { 1643 u32 changed = 0; 1644 u32 rate_flags; 1645 struct ieee80211_supported_band *sband; 1646 int i; 1647 1648 if (params->bssid) { 1649 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN); 1650 sdata->u.ibss.fixed_bssid = true; 1651 } else 1652 sdata->u.ibss.fixed_bssid = false; 1653 1654 sdata->u.ibss.privacy = params->privacy; 1655 sdata->u.ibss.control_port = params->control_port; 1656 sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs; 1657 sdata->u.ibss.basic_rates = params->basic_rates; 1658 1659 /* fix basic_rates if channel does not support these rates */ 1660 rate_flags = ieee80211_chandef_rate_flags(¶ms->chandef); 1661 sband = sdata->local->hw.wiphy->bands[params->chandef.chan->band]; 1662 for (i = 0; i < sband->n_bitrates; i++) { 1663 if ((rate_flags & sband->bitrates[i].flags) != rate_flags) 1664 sdata->u.ibss.basic_rates &= ~BIT(i); 1665 } 1666 memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate, 1667 sizeof(params->mcast_rate)); 1668 1669 sdata->vif.bss_conf.beacon_int = params->beacon_interval; 1670 1671 sdata->u.ibss.chandef = params->chandef; 1672 sdata->u.ibss.fixed_channel = params->channel_fixed; 1673 1674 if (params->ie) { 1675 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len, 1676 GFP_KERNEL); 1677 if (sdata->u.ibss.ie) 1678 sdata->u.ibss.ie_len = params->ie_len; 1679 } 1680 1681 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; 1682 sdata->u.ibss.ibss_join_req = jiffies; 1683 1684 memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len); 1685 sdata->u.ibss.ssid_len = params->ssid_len; 1686 1687 memcpy(&sdata->u.ibss.ht_capa, ¶ms->ht_capa, 1688 sizeof(sdata->u.ibss.ht_capa)); 1689 memcpy(&sdata->u.ibss.ht_capa_mask, ¶ms->ht_capa_mask, 1690 sizeof(sdata->u.ibss.ht_capa_mask)); 1691 1692 /* 1693 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is 1694 * reserved, but an HT STA shall protect HT transmissions as though 1695 * the HT Protection field were set to non-HT mixed mode. 1696 * 1697 * In an IBSS, the RIFS Mode field of the HT Operation element is 1698 * also reserved, but an HT STA shall operate as though this field 1699 * were set to 1. 1700 */ 1701 1702 sdata->vif.bss_conf.ht_operation_mode |= 1703 IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED 1704 | IEEE80211_HT_PARAM_RIFS_MODE; 1705 1706 changed |= BSS_CHANGED_HT; 1707 ieee80211_bss_info_change_notify(sdata, changed); 1708 1709 sdata->smps_mode = IEEE80211_SMPS_OFF; 1710 sdata->needed_rx_chains = sdata->local->rx_chains; 1711 1712 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 1713 1714 return 0; 1715 } 1716 1717 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata) 1718 { 1719 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1720 1721 ieee80211_ibss_disconnect(sdata); 1722 ifibss->ssid_len = 0; 1723 memset(ifibss->bssid, 0, ETH_ALEN); 1724 1725 /* remove beacon */ 1726 kfree(sdata->u.ibss.ie); 1727 1728 /* on the next join, re-program HT parameters */ 1729 memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa)); 1730 memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask)); 1731 1732 synchronize_rcu(); 1733 1734 skb_queue_purge(&sdata->skb_queue); 1735 1736 del_timer_sync(&sdata->u.ibss.timer); 1737 1738 return 0; 1739 } 1740