ibss.c revision dbd72850dcc9738b42a9762ef8c4a1a66b30d897
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 37static struct beacon_data * 38ieee80211_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; 209error: 210 kfree(presp); 211 return NULL; 212} 213 214static 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 sdata->radar_required = radar_required; 307 mutex_unlock(&local->mtx); 308 309 memcpy(ifibss->bssid, bssid, ETH_ALEN); 310 311 sband = local->hw.wiphy->bands[chan->band]; 312 313 presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates, 314 capability, tsf, &chandef, 315 &have_higher_than_11mbit, NULL); 316 if (!presp) 317 return; 318 319 rcu_assign_pointer(ifibss->presp, presp); 320 mgmt = (void *)presp->head; 321 322 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 392static 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 472int 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 return BSS_CHANGED_BEACON; 525 out: 526 return ret; 527} 528 529int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata) 530{ 531 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 532 struct cfg80211_bss *cbss; 533 int err, changed = 0; 534 u16 capability; 535 536 sdata_assert_lock(sdata); 537 538 /* update cfg80211 bss information with the new channel */ 539 if (!is_zero_ether_addr(ifibss->bssid)) { 540 capability = WLAN_CAPABILITY_IBSS; 541 542 if (ifibss->privacy) 543 capability |= WLAN_CAPABILITY_PRIVACY; 544 545 cbss = cfg80211_get_bss(sdata->local->hw.wiphy, 546 ifibss->chandef.chan, 547 ifibss->bssid, ifibss->ssid, 548 ifibss->ssid_len, WLAN_CAPABILITY_IBSS | 549 WLAN_CAPABILITY_PRIVACY, 550 capability); 551 /* XXX: should not really modify cfg80211 data */ 552 if (cbss) { 553 cbss->channel = sdata->csa_chandef.chan; 554 cfg80211_put_bss(sdata->local->hw.wiphy, cbss); 555 } 556 } 557 558 ifibss->chandef = sdata->csa_chandef; 559 560 /* generate the beacon */ 561 err = ieee80211_ibss_csa_beacon(sdata, NULL); 562 if (err < 0) 563 return err; 564 565 changed |= err; 566 567 return changed; 568} 569 570void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata) 571{ 572 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 573 574 cancel_work_sync(&ifibss->csa_connection_drop_work); 575} 576 577static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta) 578 __acquires(RCU) 579{ 580 struct ieee80211_sub_if_data *sdata = sta->sdata; 581 u8 addr[ETH_ALEN]; 582 583 memcpy(addr, sta->sta.addr, ETH_ALEN); 584 585 ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr); 586 587 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH); 588 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC); 589 /* authorize the station only if the network is not RSN protected. If 590 * not wait for the userspace to authorize it */ 591 if (!sta->sdata->u.ibss.control_port) 592 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED); 593 594 rate_control_rate_init(sta); 595 596 /* If it fails, maybe we raced another insertion? */ 597 if (sta_info_insert_rcu(sta)) 598 return sta_info_get(sdata, addr); 599 return sta; 600} 601 602static struct sta_info * 603ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid, 604 const u8 *addr, u32 supp_rates) 605 __acquires(RCU) 606{ 607 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 608 struct ieee80211_local *local = sdata->local; 609 struct sta_info *sta; 610 struct ieee80211_chanctx_conf *chanctx_conf; 611 struct ieee80211_supported_band *sband; 612 enum nl80211_bss_scan_width scan_width; 613 int band; 614 615 /* 616 * XXX: Consider removing the least recently used entry and 617 * allow new one to be added. 618 */ 619 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 620 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n", 621 sdata->name, addr); 622 rcu_read_lock(); 623 return NULL; 624 } 625 626 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) { 627 rcu_read_lock(); 628 return NULL; 629 } 630 631 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) { 632 rcu_read_lock(); 633 return NULL; 634 } 635 636 rcu_read_lock(); 637 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); 638 if (WARN_ON_ONCE(!chanctx_conf)) 639 return NULL; 640 band = chanctx_conf->def.chan->band; 641 scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def); 642 rcu_read_unlock(); 643 644 sta = sta_info_alloc(sdata, addr, GFP_KERNEL); 645 if (!sta) { 646 rcu_read_lock(); 647 return NULL; 648 } 649 650 sta->last_rx = jiffies; 651 652 /* make sure mandatory rates are always added */ 653 sband = local->hw.wiphy->bands[band]; 654 sta->sta.supp_rates[band] = supp_rates | 655 ieee80211_mandatory_rates(sband, scan_width); 656 657 return ieee80211_ibss_finish_sta(sta); 658} 659 660static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata) 661{ 662 struct ieee80211_local *local = sdata->local; 663 int active = 0; 664 struct sta_info *sta; 665 666 sdata_assert_lock(sdata); 667 668 rcu_read_lock(); 669 670 list_for_each_entry_rcu(sta, &local->sta_list, list) { 671 if (sta->sdata == sdata && 672 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL, 673 jiffies)) { 674 active++; 675 break; 676 } 677 } 678 679 rcu_read_unlock(); 680 681 return active; 682} 683 684static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata) 685{ 686 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 687 struct ieee80211_local *local = sdata->local; 688 struct cfg80211_bss *cbss; 689 struct beacon_data *presp; 690 struct sta_info *sta; 691 int active_ibss; 692 u16 capability; 693 694 active_ibss = ieee80211_sta_active_ibss(sdata); 695 696 if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) { 697 capability = WLAN_CAPABILITY_IBSS; 698 699 if (ifibss->privacy) 700 capability |= WLAN_CAPABILITY_PRIVACY; 701 702 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan, 703 ifibss->bssid, ifibss->ssid, 704 ifibss->ssid_len, WLAN_CAPABILITY_IBSS | 705 WLAN_CAPABILITY_PRIVACY, 706 capability); 707 708 if (cbss) { 709 cfg80211_unlink_bss(local->hw.wiphy, cbss); 710 cfg80211_put_bss(sdata->local->hw.wiphy, cbss); 711 } 712 } 713 714 ifibss->state = IEEE80211_IBSS_MLME_SEARCH; 715 716 sta_info_flush(sdata); 717 718 spin_lock_bh(&ifibss->incomplete_lock); 719 while (!list_empty(&ifibss->incomplete_stations)) { 720 sta = list_first_entry(&ifibss->incomplete_stations, 721 struct sta_info, list); 722 list_del(&sta->list); 723 spin_unlock_bh(&ifibss->incomplete_lock); 724 725 sta_info_free(local, sta); 726 spin_lock_bh(&ifibss->incomplete_lock); 727 } 728 spin_unlock_bh(&ifibss->incomplete_lock); 729 730 netif_carrier_off(sdata->dev); 731 732 sdata->vif.bss_conf.ibss_joined = false; 733 sdata->vif.bss_conf.ibss_creator = false; 734 sdata->vif.bss_conf.enable_beacon = false; 735 sdata->vif.bss_conf.ssid_len = 0; 736 737 /* remove beacon */ 738 presp = rcu_dereference_protected(ifibss->presp, 739 lockdep_is_held(&sdata->wdev.mtx)); 740 RCU_INIT_POINTER(sdata->u.ibss.presp, NULL); 741 if (presp) 742 kfree_rcu(presp, rcu_head); 743 744 clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state); 745 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED | 746 BSS_CHANGED_IBSS); 747 drv_leave_ibss(local, sdata); 748 mutex_lock(&local->mtx); 749 ieee80211_vif_release_channel(sdata); 750 mutex_unlock(&local->mtx); 751} 752 753static void ieee80211_csa_connection_drop_work(struct work_struct *work) 754{ 755 struct ieee80211_sub_if_data *sdata = 756 container_of(work, struct ieee80211_sub_if_data, 757 u.ibss.csa_connection_drop_work); 758 759 sdata_lock(sdata); 760 761 ieee80211_ibss_disconnect(sdata); 762 synchronize_rcu(); 763 skb_queue_purge(&sdata->skb_queue); 764 765 /* trigger a scan to find another IBSS network to join */ 766 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 767 768 sdata_unlock(sdata); 769} 770 771static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata) 772{ 773 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 774 int err; 775 776 /* if the current channel is a DFS channel, mark the channel as 777 * unavailable. 778 */ 779 err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy, 780 &ifibss->chandef); 781 if (err > 0) 782 cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef, 783 GFP_ATOMIC); 784} 785 786static bool 787ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata, 788 struct ieee802_11_elems *elems, 789 bool beacon) 790{ 791 struct cfg80211_csa_settings params; 792 struct ieee80211_csa_ie csa_ie; 793 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 794 enum nl80211_channel_type ch_type; 795 int err; 796 u32 sta_flags; 797 798 sdata_assert_lock(sdata); 799 800 sta_flags = IEEE80211_STA_DISABLE_VHT; 801 switch (ifibss->chandef.width) { 802 case NL80211_CHAN_WIDTH_5: 803 case NL80211_CHAN_WIDTH_10: 804 case NL80211_CHAN_WIDTH_20_NOHT: 805 sta_flags |= IEEE80211_STA_DISABLE_HT; 806 /* fall through */ 807 case NL80211_CHAN_WIDTH_20: 808 sta_flags |= IEEE80211_STA_DISABLE_40MHZ; 809 break; 810 default: 811 break; 812 } 813 814 memset(¶ms, 0, sizeof(params)); 815 memset(&csa_ie, 0, sizeof(csa_ie)); 816 err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon, 817 ifibss->chandef.chan->band, 818 sta_flags, ifibss->bssid, &csa_ie); 819 /* can't switch to destination channel, fail */ 820 if (err < 0) 821 goto disconnect; 822 823 /* did not contain a CSA */ 824 if (err) 825 return false; 826 827 /* channel switch is not supported, disconnect */ 828 if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH)) 829 goto disconnect; 830 831 params.count = csa_ie.count; 832 params.chandef = csa_ie.chandef; 833 834 switch (ifibss->chandef.width) { 835 case NL80211_CHAN_WIDTH_20_NOHT: 836 case NL80211_CHAN_WIDTH_20: 837 case NL80211_CHAN_WIDTH_40: 838 /* keep our current HT mode (HT20/HT40+/HT40-), even if 839 * another mode has been announced. The mode is not adopted 840 * within the beacon while doing CSA and we should therefore 841 * keep the mode which we announce. 842 */ 843 ch_type = cfg80211_get_chandef_type(&ifibss->chandef); 844 cfg80211_chandef_create(¶ms.chandef, params.chandef.chan, 845 ch_type); 846 break; 847 case NL80211_CHAN_WIDTH_5: 848 case NL80211_CHAN_WIDTH_10: 849 if (params.chandef.width != ifibss->chandef.width) { 850 sdata_info(sdata, 851 "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n", 852 ifibss->bssid, 853 params.chandef.chan->center_freq, 854 params.chandef.width, 855 params.chandef.center_freq1, 856 params.chandef.center_freq2); 857 goto disconnect; 858 } 859 break; 860 default: 861 /* should not happen, sta_flags should prevent VHT modes. */ 862 WARN_ON(1); 863 goto disconnect; 864 } 865 866 if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, ¶ms.chandef)) { 867 sdata_info(sdata, 868 "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n", 869 ifibss->bssid, 870 params.chandef.chan->center_freq, 871 params.chandef.width, 872 params.chandef.center_freq1, 873 params.chandef.center_freq2); 874 goto disconnect; 875 } 876 877 err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy, 878 ¶ms.chandef); 879 if (err < 0) 880 goto disconnect; 881 if (err) { 882 /* IBSS-DFS only allowed with a control program */ 883 if (!ifibss->userspace_handles_dfs) 884 goto disconnect; 885 886 params.radar_required = true; 887 } 888 889 if (cfg80211_chandef_identical(¶ms.chandef, 890 &sdata->vif.bss_conf.chandef)) { 891 ibss_dbg(sdata, 892 "received csa with an identical chandef, ignoring\n"); 893 return true; 894 } 895 896 /* all checks done, now perform the channel switch. */ 897 ibss_dbg(sdata, 898 "received channel switch announcement to go to channel %d MHz\n", 899 params.chandef.chan->center_freq); 900 901 params.block_tx = !!csa_ie.mode; 902 903 if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev, 904 ¶ms)) 905 goto disconnect; 906 907 ieee80211_ibss_csa_mark_radar(sdata); 908 909 return true; 910disconnect: 911 ibss_dbg(sdata, "Can't handle channel switch, disconnect\n"); 912 ieee80211_queue_work(&sdata->local->hw, 913 &ifibss->csa_connection_drop_work); 914 915 ieee80211_ibss_csa_mark_radar(sdata); 916 917 return true; 918} 919 920static void 921ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata, 922 struct ieee80211_mgmt *mgmt, size_t len, 923 struct ieee80211_rx_status *rx_status, 924 struct ieee802_11_elems *elems) 925{ 926 int required_len; 927 928 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 929 return; 930 931 /* CSA is the only action we handle for now */ 932 if (mgmt->u.action.u.measurement.action_code != 933 WLAN_ACTION_SPCT_CHL_SWITCH) 934 return; 935 936 required_len = IEEE80211_MIN_ACTION_SIZE + 937 sizeof(mgmt->u.action.u.chan_switch); 938 if (len < required_len) 939 return; 940 941 if (!sdata->vif.csa_active) 942 ieee80211_ibss_process_chanswitch(sdata, elems, false); 943} 944 945static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata, 946 struct ieee80211_mgmt *mgmt, 947 size_t len) 948{ 949 u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code); 950 951 if (len < IEEE80211_DEAUTH_FRAME_LEN) 952 return; 953 954 ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n", 955 mgmt->sa, mgmt->da, mgmt->bssid, reason); 956 sta_info_destroy_addr(sdata, mgmt->sa); 957} 958 959static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata, 960 struct ieee80211_mgmt *mgmt, 961 size_t len) 962{ 963 u16 auth_alg, auth_transaction; 964 965 sdata_assert_lock(sdata); 966 967 if (len < 24 + 6) 968 return; 969 970 auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg); 971 auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction); 972 973 ibss_dbg(sdata, 974 "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n", 975 mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction); 976 977 if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1) 978 return; 979 980 /* 981 * IEEE 802.11 standard does not require authentication in IBSS 982 * networks and most implementations do not seem to use it. 983 * However, try to reply to authentication attempts if someone 984 * has actually implemented this. 985 */ 986 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0, 987 mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0); 988} 989 990static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, 991 struct ieee80211_mgmt *mgmt, size_t len, 992 struct ieee80211_rx_status *rx_status, 993 struct ieee802_11_elems *elems) 994{ 995 struct ieee80211_local *local = sdata->local; 996 int freq; 997 struct cfg80211_bss *cbss; 998 struct ieee80211_bss *bss; 999 struct sta_info *sta; 1000 struct ieee80211_channel *channel; 1001 u64 beacon_timestamp, rx_timestamp; 1002 u32 supp_rates = 0; 1003 enum ieee80211_band band = rx_status->band; 1004 enum nl80211_bss_scan_width scan_width; 1005 struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band]; 1006 bool rates_updated = false; 1007 1008 if (elems->ds_params) 1009 freq = ieee80211_channel_to_frequency(elems->ds_params[0], 1010 band); 1011 else 1012 freq = rx_status->freq; 1013 1014 channel = ieee80211_get_channel(local->hw.wiphy, freq); 1015 1016 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 1017 return; 1018 1019 if (sdata->vif.type == NL80211_IFTYPE_ADHOC && 1020 ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) { 1021 1022 rcu_read_lock(); 1023 sta = sta_info_get(sdata, mgmt->sa); 1024 1025 if (elems->supp_rates) { 1026 supp_rates = ieee80211_sta_get_rates(sdata, elems, 1027 band, NULL); 1028 if (sta) { 1029 u32 prev_rates; 1030 1031 prev_rates = sta->sta.supp_rates[band]; 1032 /* make sure mandatory rates are always added */ 1033 scan_width = NL80211_BSS_CHAN_WIDTH_20; 1034 if (rx_status->flag & RX_FLAG_5MHZ) 1035 scan_width = NL80211_BSS_CHAN_WIDTH_5; 1036 if (rx_status->flag & RX_FLAG_10MHZ) 1037 scan_width = NL80211_BSS_CHAN_WIDTH_10; 1038 1039 sta->sta.supp_rates[band] = supp_rates | 1040 ieee80211_mandatory_rates(sband, 1041 scan_width); 1042 if (sta->sta.supp_rates[band] != prev_rates) { 1043 ibss_dbg(sdata, 1044 "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n", 1045 sta->sta.addr, prev_rates, 1046 sta->sta.supp_rates[band]); 1047 rates_updated = true; 1048 } 1049 } else { 1050 rcu_read_unlock(); 1051 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, 1052 mgmt->sa, supp_rates); 1053 } 1054 } 1055 1056 if (sta && elems->wmm_info) 1057 set_sta_flag(sta, WLAN_STA_WME); 1058 1059 if (sta && elems->ht_operation && elems->ht_cap_elem && 1060 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT && 1061 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 && 1062 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) { 1063 /* we both use HT */ 1064 struct ieee80211_ht_cap htcap_ie; 1065 struct cfg80211_chan_def chandef; 1066 1067 ieee80211_ht_oper_to_chandef(channel, 1068 elems->ht_operation, 1069 &chandef); 1070 1071 memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie)); 1072 1073 /* 1074 * fall back to HT20 if we don't use or use 1075 * the other extension channel 1076 */ 1077 if (chandef.center_freq1 != 1078 sdata->u.ibss.chandef.center_freq1) 1079 htcap_ie.cap_info &= 1080 cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40); 1081 1082 rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap( 1083 sdata, sband, &htcap_ie, sta); 1084 } 1085 1086 if (sta && rates_updated) { 1087 drv_sta_rc_update(local, sdata, &sta->sta, 1088 IEEE80211_RC_SUPP_RATES_CHANGED); 1089 rate_control_rate_init(sta); 1090 } 1091 1092 rcu_read_unlock(); 1093 } 1094 1095 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems, 1096 channel); 1097 if (!bss) 1098 return; 1099 1100 cbss = container_of((void *)bss, struct cfg80211_bss, priv); 1101 1102 /* same for beacon and probe response */ 1103 beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp); 1104 1105 /* check if we need to merge IBSS */ 1106 1107 /* not an IBSS */ 1108 if (!(cbss->capability & WLAN_CAPABILITY_IBSS)) 1109 goto put_bss; 1110 1111 /* different channel */ 1112 if (sdata->u.ibss.fixed_channel && 1113 sdata->u.ibss.chandef.chan != cbss->channel) 1114 goto put_bss; 1115 1116 /* different SSID */ 1117 if (elems->ssid_len != sdata->u.ibss.ssid_len || 1118 memcmp(elems->ssid, sdata->u.ibss.ssid, 1119 sdata->u.ibss.ssid_len)) 1120 goto put_bss; 1121 1122 /* process channel switch */ 1123 if (sdata->vif.csa_active || 1124 ieee80211_ibss_process_chanswitch(sdata, elems, true)) 1125 goto put_bss; 1126 1127 /* same BSSID */ 1128 if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid)) 1129 goto put_bss; 1130 1131 /* we use a fixed BSSID */ 1132 if (sdata->u.ibss.fixed_bssid) 1133 goto put_bss; 1134 1135 if (ieee80211_have_rx_timestamp(rx_status)) { 1136 /* time when timestamp field was received */ 1137 rx_timestamp = 1138 ieee80211_calculate_rx_timestamp(local, rx_status, 1139 len + FCS_LEN, 24); 1140 } else { 1141 /* 1142 * second best option: get current TSF 1143 * (will return -1 if not supported) 1144 */ 1145 rx_timestamp = drv_get_tsf(local, sdata); 1146 } 1147 1148 ibss_dbg(sdata, 1149 "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n", 1150 mgmt->sa, mgmt->bssid, 1151 (unsigned long long)rx_timestamp, 1152 (unsigned long long)beacon_timestamp, 1153 (unsigned long long)(rx_timestamp - beacon_timestamp), 1154 jiffies); 1155 1156 if (beacon_timestamp > rx_timestamp) { 1157 ibss_dbg(sdata, 1158 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n", 1159 mgmt->bssid); 1160 ieee80211_sta_join_ibss(sdata, bss); 1161 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL); 1162 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 1163 supp_rates); 1164 rcu_read_unlock(); 1165 } 1166 1167 put_bss: 1168 ieee80211_rx_bss_put(local, bss); 1169} 1170 1171void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata, 1172 const u8 *bssid, const u8 *addr, 1173 u32 supp_rates) 1174{ 1175 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1176 struct ieee80211_local *local = sdata->local; 1177 struct sta_info *sta; 1178 struct ieee80211_chanctx_conf *chanctx_conf; 1179 struct ieee80211_supported_band *sband; 1180 enum nl80211_bss_scan_width scan_width; 1181 int band; 1182 1183 /* 1184 * XXX: Consider removing the least recently used entry and 1185 * allow new one to be added. 1186 */ 1187 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 1188 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n", 1189 sdata->name, addr); 1190 return; 1191 } 1192 1193 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) 1194 return; 1195 1196 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) 1197 return; 1198 1199 rcu_read_lock(); 1200 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); 1201 if (WARN_ON_ONCE(!chanctx_conf)) { 1202 rcu_read_unlock(); 1203 return; 1204 } 1205 band = chanctx_conf->def.chan->band; 1206 scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def); 1207 rcu_read_unlock(); 1208 1209 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC); 1210 if (!sta) 1211 return; 1212 1213 sta->last_rx = jiffies; 1214 1215 /* make sure mandatory rates are always added */ 1216 sband = local->hw.wiphy->bands[band]; 1217 sta->sta.supp_rates[band] = supp_rates | 1218 ieee80211_mandatory_rates(sband, scan_width); 1219 1220 spin_lock(&ifibss->incomplete_lock); 1221 list_add(&sta->list, &ifibss->incomplete_stations); 1222 spin_unlock(&ifibss->incomplete_lock); 1223 ieee80211_queue_work(&local->hw, &sdata->work); 1224} 1225 1226static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata) 1227{ 1228 struct ieee80211_local *local = sdata->local; 1229 struct sta_info *sta, *tmp; 1230 unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT; 1231 unsigned long exp_rsn_time = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT; 1232 1233 mutex_lock(&local->sta_mtx); 1234 1235 list_for_each_entry_safe(sta, tmp, &local->sta_list, list) { 1236 if (sdata != sta->sdata) 1237 continue; 1238 1239 if (time_after(jiffies, sta->last_rx + exp_time) || 1240 (time_after(jiffies, sta->last_rx + exp_rsn_time) && 1241 sta->sta_state != IEEE80211_STA_AUTHORIZED)) { 1242 sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n", 1243 sta->sta_state != IEEE80211_STA_AUTHORIZED ? 1244 "not authorized " : "", sta->sta.addr); 1245 1246 WARN_ON(__sta_info_destroy(sta)); 1247 } 1248 } 1249 1250 mutex_unlock(&local->sta_mtx); 1251} 1252 1253/* 1254 * This function is called with state == IEEE80211_IBSS_MLME_JOINED 1255 */ 1256 1257static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata) 1258{ 1259 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1260 enum nl80211_bss_scan_width scan_width; 1261 1262 sdata_assert_lock(sdata); 1263 1264 mod_timer(&ifibss->timer, 1265 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 1266 1267 ieee80211_ibss_sta_expire(sdata); 1268 1269 if (time_before(jiffies, ifibss->last_scan_completed + 1270 IEEE80211_IBSS_MERGE_INTERVAL)) 1271 return; 1272 1273 if (ieee80211_sta_active_ibss(sdata)) 1274 return; 1275 1276 if (ifibss->fixed_channel) 1277 return; 1278 1279 sdata_info(sdata, 1280 "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n"); 1281 1282 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef); 1283 ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len, 1284 NULL, scan_width); 1285} 1286 1287static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata) 1288{ 1289 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1290 u8 bssid[ETH_ALEN]; 1291 u16 capability; 1292 int i; 1293 1294 sdata_assert_lock(sdata); 1295 1296 if (ifibss->fixed_bssid) { 1297 memcpy(bssid, ifibss->bssid, ETH_ALEN); 1298 } else { 1299 /* Generate random, not broadcast, locally administered BSSID. Mix in 1300 * own MAC address to make sure that devices that do not have proper 1301 * random number generator get different BSSID. */ 1302 get_random_bytes(bssid, ETH_ALEN); 1303 for (i = 0; i < ETH_ALEN; i++) 1304 bssid[i] ^= sdata->vif.addr[i]; 1305 bssid[0] &= ~0x01; 1306 bssid[0] |= 0x02; 1307 } 1308 1309 sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid); 1310 1311 capability = WLAN_CAPABILITY_IBSS; 1312 1313 if (ifibss->privacy) 1314 capability |= WLAN_CAPABILITY_PRIVACY; 1315 else 1316 sdata->drop_unencrypted = 0; 1317 1318 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int, 1319 &ifibss->chandef, ifibss->basic_rates, 1320 capability, 0, true); 1321} 1322 1323/* 1324 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH 1325 */ 1326 1327static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata) 1328{ 1329 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1330 struct ieee80211_local *local = sdata->local; 1331 struct cfg80211_bss *cbss; 1332 struct ieee80211_channel *chan = NULL; 1333 const u8 *bssid = NULL; 1334 enum nl80211_bss_scan_width scan_width; 1335 int active_ibss; 1336 u16 capability; 1337 1338 sdata_assert_lock(sdata); 1339 1340 active_ibss = ieee80211_sta_active_ibss(sdata); 1341 ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss); 1342 1343 if (active_ibss) 1344 return; 1345 1346 capability = WLAN_CAPABILITY_IBSS; 1347 if (ifibss->privacy) 1348 capability |= WLAN_CAPABILITY_PRIVACY; 1349 if (ifibss->fixed_bssid) 1350 bssid = ifibss->bssid; 1351 if (ifibss->fixed_channel) 1352 chan = ifibss->chandef.chan; 1353 if (!is_zero_ether_addr(ifibss->bssid)) 1354 bssid = ifibss->bssid; 1355 cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid, 1356 ifibss->ssid, ifibss->ssid_len, 1357 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY, 1358 capability); 1359 1360 if (cbss) { 1361 struct ieee80211_bss *bss; 1362 1363 bss = (void *)cbss->priv; 1364 ibss_dbg(sdata, 1365 "sta_find_ibss: selected %pM current %pM\n", 1366 cbss->bssid, ifibss->bssid); 1367 sdata_info(sdata, 1368 "Selected IBSS BSSID %pM based on configured SSID\n", 1369 cbss->bssid); 1370 1371 ieee80211_sta_join_ibss(sdata, bss); 1372 ieee80211_rx_bss_put(local, bss); 1373 return; 1374 } 1375 1376 /* if a fixed bssid and a fixed freq have been provided create the IBSS 1377 * directly and do not waste time scanning 1378 */ 1379 if (ifibss->fixed_bssid && ifibss->fixed_channel) { 1380 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n", 1381 bssid); 1382 ieee80211_sta_create_ibss(sdata); 1383 return; 1384 } 1385 1386 1387 ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n"); 1388 1389 /* Selected IBSS not found in current scan results - try to scan */ 1390 if (time_after(jiffies, ifibss->last_scan_completed + 1391 IEEE80211_SCAN_INTERVAL)) { 1392 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n"); 1393 1394 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef); 1395 ieee80211_request_ibss_scan(sdata, ifibss->ssid, 1396 ifibss->ssid_len, chan, 1397 scan_width); 1398 } else { 1399 int interval = IEEE80211_SCAN_INTERVAL; 1400 1401 if (time_after(jiffies, ifibss->ibss_join_req + 1402 IEEE80211_IBSS_JOIN_TIMEOUT)) 1403 ieee80211_sta_create_ibss(sdata); 1404 1405 mod_timer(&ifibss->timer, 1406 round_jiffies(jiffies + interval)); 1407 } 1408} 1409 1410static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata, 1411 struct sk_buff *req) 1412{ 1413 struct ieee80211_mgmt *mgmt = (void *)req->data; 1414 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1415 struct ieee80211_local *local = sdata->local; 1416 int tx_last_beacon, len = req->len; 1417 struct sk_buff *skb; 1418 struct beacon_data *presp; 1419 u8 *pos, *end; 1420 1421 sdata_assert_lock(sdata); 1422 1423 presp = rcu_dereference_protected(ifibss->presp, 1424 lockdep_is_held(&sdata->wdev.mtx)); 1425 1426 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED || 1427 len < 24 + 2 || !presp) 1428 return; 1429 1430 tx_last_beacon = drv_tx_last_beacon(local); 1431 1432 ibss_dbg(sdata, 1433 "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n", 1434 mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon); 1435 1436 if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da)) 1437 return; 1438 1439 if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) && 1440 !is_broadcast_ether_addr(mgmt->bssid)) 1441 return; 1442 1443 end = ((u8 *) mgmt) + len; 1444 pos = mgmt->u.probe_req.variable; 1445 if (pos[0] != WLAN_EID_SSID || 1446 pos + 2 + pos[1] > end) { 1447 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n", 1448 mgmt->sa); 1449 return; 1450 } 1451 if (pos[1] != 0 && 1452 (pos[1] != ifibss->ssid_len || 1453 memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) { 1454 /* Ignore ProbeReq for foreign SSID */ 1455 return; 1456 } 1457 1458 /* Reply with ProbeResp */ 1459 skb = dev_alloc_skb(local->tx_headroom + presp->head_len); 1460 if (!skb) 1461 return; 1462 1463 skb_reserve(skb, local->tx_headroom); 1464 memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len); 1465 1466 memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN); 1467 ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa); 1468 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 1469 ieee80211_tx_skb(sdata, skb); 1470} 1471 1472static 1473void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata, 1474 struct ieee80211_mgmt *mgmt, size_t len, 1475 struct ieee80211_rx_status *rx_status) 1476{ 1477 size_t baselen; 1478 struct ieee802_11_elems elems; 1479 1480 BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) != 1481 offsetof(typeof(mgmt->u.beacon), variable)); 1482 1483 /* 1484 * either beacon or probe_resp but the variable field is at the 1485 * same offset 1486 */ 1487 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt; 1488 if (baselen > len) 1489 return; 1490 1491 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen, 1492 false, &elems); 1493 1494 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems); 1495} 1496 1497void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata, 1498 struct sk_buff *skb) 1499{ 1500 struct ieee80211_rx_status *rx_status; 1501 struct ieee80211_mgmt *mgmt; 1502 u16 fc; 1503 struct ieee802_11_elems elems; 1504 int ies_len; 1505 1506 rx_status = IEEE80211_SKB_RXCB(skb); 1507 mgmt = (struct ieee80211_mgmt *) skb->data; 1508 fc = le16_to_cpu(mgmt->frame_control); 1509 1510 sdata_lock(sdata); 1511 1512 if (!sdata->u.ibss.ssid_len) 1513 goto mgmt_out; /* not ready to merge yet */ 1514 1515 switch (fc & IEEE80211_FCTL_STYPE) { 1516 case IEEE80211_STYPE_PROBE_REQ: 1517 ieee80211_rx_mgmt_probe_req(sdata, skb); 1518 break; 1519 case IEEE80211_STYPE_PROBE_RESP: 1520 case IEEE80211_STYPE_BEACON: 1521 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len, 1522 rx_status); 1523 break; 1524 case IEEE80211_STYPE_AUTH: 1525 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len); 1526 break; 1527 case IEEE80211_STYPE_DEAUTH: 1528 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len); 1529 break; 1530 case IEEE80211_STYPE_ACTION: 1531 switch (mgmt->u.action.category) { 1532 case WLAN_CATEGORY_SPECTRUM_MGMT: 1533 ies_len = skb->len - 1534 offsetof(struct ieee80211_mgmt, 1535 u.action.u.chan_switch.variable); 1536 1537 if (ies_len < 0) 1538 break; 1539 1540 ieee802_11_parse_elems( 1541 mgmt->u.action.u.chan_switch.variable, 1542 ies_len, true, &elems); 1543 1544 if (elems.parse_error) 1545 break; 1546 1547 ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len, 1548 rx_status, &elems); 1549 break; 1550 } 1551 } 1552 1553 mgmt_out: 1554 sdata_unlock(sdata); 1555} 1556 1557void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata) 1558{ 1559 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1560 struct sta_info *sta; 1561 1562 sdata_lock(sdata); 1563 1564 /* 1565 * Work could be scheduled after scan or similar 1566 * when we aren't even joined (or trying) with a 1567 * network. 1568 */ 1569 if (!ifibss->ssid_len) 1570 goto out; 1571 1572 spin_lock_bh(&ifibss->incomplete_lock); 1573 while (!list_empty(&ifibss->incomplete_stations)) { 1574 sta = list_first_entry(&ifibss->incomplete_stations, 1575 struct sta_info, list); 1576 list_del(&sta->list); 1577 spin_unlock_bh(&ifibss->incomplete_lock); 1578 1579 ieee80211_ibss_finish_sta(sta); 1580 rcu_read_unlock(); 1581 spin_lock_bh(&ifibss->incomplete_lock); 1582 } 1583 spin_unlock_bh(&ifibss->incomplete_lock); 1584 1585 switch (ifibss->state) { 1586 case IEEE80211_IBSS_MLME_SEARCH: 1587 ieee80211_sta_find_ibss(sdata); 1588 break; 1589 case IEEE80211_IBSS_MLME_JOINED: 1590 ieee80211_sta_merge_ibss(sdata); 1591 break; 1592 default: 1593 WARN_ON(1); 1594 break; 1595 } 1596 1597 out: 1598 sdata_unlock(sdata); 1599} 1600 1601static void ieee80211_ibss_timer(unsigned long data) 1602{ 1603 struct ieee80211_sub_if_data *sdata = 1604 (struct ieee80211_sub_if_data *) data; 1605 1606 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 1607} 1608 1609void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata) 1610{ 1611 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1612 1613 setup_timer(&ifibss->timer, ieee80211_ibss_timer, 1614 (unsigned long) sdata); 1615 INIT_LIST_HEAD(&ifibss->incomplete_stations); 1616 spin_lock_init(&ifibss->incomplete_lock); 1617 INIT_WORK(&ifibss->csa_connection_drop_work, 1618 ieee80211_csa_connection_drop_work); 1619} 1620 1621/* scan finished notification */ 1622void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local) 1623{ 1624 struct ieee80211_sub_if_data *sdata; 1625 1626 mutex_lock(&local->iflist_mtx); 1627 list_for_each_entry(sdata, &local->interfaces, list) { 1628 if (!ieee80211_sdata_running(sdata)) 1629 continue; 1630 if (sdata->vif.type != NL80211_IFTYPE_ADHOC) 1631 continue; 1632 sdata->u.ibss.last_scan_completed = jiffies; 1633 ieee80211_queue_work(&local->hw, &sdata->work); 1634 } 1635 mutex_unlock(&local->iflist_mtx); 1636} 1637 1638int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata, 1639 struct cfg80211_ibss_params *params) 1640{ 1641 u32 changed = 0; 1642 u32 rate_flags; 1643 struct ieee80211_supported_band *sband; 1644 int i; 1645 1646 if (params->bssid) { 1647 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN); 1648 sdata->u.ibss.fixed_bssid = true; 1649 } else 1650 sdata->u.ibss.fixed_bssid = false; 1651 1652 sdata->u.ibss.privacy = params->privacy; 1653 sdata->u.ibss.control_port = params->control_port; 1654 sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs; 1655 sdata->u.ibss.basic_rates = params->basic_rates; 1656 1657 /* fix basic_rates if channel does not support these rates */ 1658 rate_flags = ieee80211_chandef_rate_flags(¶ms->chandef); 1659 sband = sdata->local->hw.wiphy->bands[params->chandef.chan->band]; 1660 for (i = 0; i < sband->n_bitrates; i++) { 1661 if ((rate_flags & sband->bitrates[i].flags) != rate_flags) 1662 sdata->u.ibss.basic_rates &= ~BIT(i); 1663 } 1664 memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate, 1665 sizeof(params->mcast_rate)); 1666 1667 sdata->vif.bss_conf.beacon_int = params->beacon_interval; 1668 1669 sdata->u.ibss.chandef = params->chandef; 1670 sdata->u.ibss.fixed_channel = params->channel_fixed; 1671 1672 if (params->ie) { 1673 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len, 1674 GFP_KERNEL); 1675 if (sdata->u.ibss.ie) 1676 sdata->u.ibss.ie_len = params->ie_len; 1677 } 1678 1679 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; 1680 sdata->u.ibss.ibss_join_req = jiffies; 1681 1682 memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len); 1683 sdata->u.ibss.ssid_len = params->ssid_len; 1684 1685 memcpy(&sdata->u.ibss.ht_capa, ¶ms->ht_capa, 1686 sizeof(sdata->u.ibss.ht_capa)); 1687 memcpy(&sdata->u.ibss.ht_capa_mask, ¶ms->ht_capa_mask, 1688 sizeof(sdata->u.ibss.ht_capa_mask)); 1689 1690 /* 1691 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is 1692 * reserved, but an HT STA shall protect HT transmissions as though 1693 * the HT Protection field were set to non-HT mixed mode. 1694 * 1695 * In an IBSS, the RIFS Mode field of the HT Operation element is 1696 * also reserved, but an HT STA shall operate as though this field 1697 * were set to 1. 1698 */ 1699 1700 sdata->vif.bss_conf.ht_operation_mode |= 1701 IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED 1702 | IEEE80211_HT_PARAM_RIFS_MODE; 1703 1704 changed |= BSS_CHANGED_HT; 1705 ieee80211_bss_info_change_notify(sdata, changed); 1706 1707 sdata->smps_mode = IEEE80211_SMPS_OFF; 1708 sdata->needed_rx_chains = sdata->local->rx_chains; 1709 1710 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 1711 1712 return 0; 1713} 1714 1715int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata) 1716{ 1717 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1718 1719 ieee80211_ibss_disconnect(sdata); 1720 ifibss->ssid_len = 0; 1721 memset(ifibss->bssid, 0, ETH_ALEN); 1722 1723 /* remove beacon */ 1724 kfree(sdata->u.ibss.ie); 1725 1726 /* on the next join, re-program HT parameters */ 1727 memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa)); 1728 memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask)); 1729 1730 synchronize_rcu(); 1731 1732 skb_queue_purge(&sdata->skb_queue); 1733 1734 del_timer_sync(&sdata->u.ibss.timer); 1735 1736 return 0; 1737} 1738