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 ieee80211_vif_release_channel(sdata); 297 if (ieee80211_vif_use_channel(sdata, &chandef, 298 ifibss->fixed_channel ? 299 IEEE80211_CHANCTX_SHARED : 300 IEEE80211_CHANCTX_EXCLUSIVE)) { 301 sdata_info(sdata, "Failed to join IBSS, no channel context\n"); 302 return; 303 } 304 305 memcpy(ifibss->bssid, bssid, ETH_ALEN); 306 307 sband = local->hw.wiphy->bands[chan->band]; 308 309 presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates, 310 capability, tsf, &chandef, 311 &have_higher_than_11mbit, NULL); 312 if (!presp) 313 return; 314 315 rcu_assign_pointer(ifibss->presp, presp); 316 mgmt = (void *)presp->head; 317 318 sdata->radar_required = radar_required; 319 sdata->vif.bss_conf.enable_beacon = true; 320 sdata->vif.bss_conf.beacon_int = beacon_int; 321 sdata->vif.bss_conf.basic_rates = basic_rates; 322 sdata->vif.bss_conf.ssid_len = ifibss->ssid_len; 323 memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len); 324 bss_change = BSS_CHANGED_BEACON_INT; 325 bss_change |= ieee80211_reset_erp_info(sdata); 326 bss_change |= BSS_CHANGED_BSSID; 327 bss_change |= BSS_CHANGED_BEACON; 328 bss_change |= BSS_CHANGED_BEACON_ENABLED; 329 bss_change |= BSS_CHANGED_BASIC_RATES; 330 bss_change |= BSS_CHANGED_HT; 331 bss_change |= BSS_CHANGED_IBSS; 332 bss_change |= BSS_CHANGED_SSID; 333 334 /* 335 * In 5 GHz/802.11a, we can always use short slot time. 336 * (IEEE 802.11-2012 18.3.8.7) 337 * 338 * In 2.4GHz, we must always use long slots in IBSS for compatibility 339 * reasons. 340 * (IEEE 802.11-2012 19.4.5) 341 * 342 * HT follows these specifications (IEEE 802.11-2012 20.3.18) 343 */ 344 sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ; 345 bss_change |= BSS_CHANGED_ERP_SLOT; 346 347 /* cf. IEEE 802.11 9.2.12 */ 348 if (chan->band == IEEE80211_BAND_2GHZ && have_higher_than_11mbit) 349 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE; 350 else 351 sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE; 352 353 ieee80211_set_wmm_default(sdata, true); 354 355 sdata->vif.bss_conf.ibss_joined = true; 356 sdata->vif.bss_conf.ibss_creator = creator; 357 358 err = drv_join_ibss(local, sdata); 359 if (err) { 360 sdata->vif.bss_conf.ibss_joined = false; 361 sdata->vif.bss_conf.ibss_creator = false; 362 sdata->vif.bss_conf.enable_beacon = false; 363 sdata->vif.bss_conf.ssid_len = 0; 364 RCU_INIT_POINTER(ifibss->presp, NULL); 365 kfree_rcu(presp, rcu_head); 366 ieee80211_vif_release_channel(sdata); 367 sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n", 368 err); 369 return; 370 } 371 372 ieee80211_bss_info_change_notify(sdata, bss_change); 373 374 ifibss->state = IEEE80211_IBSS_MLME_JOINED; 375 mod_timer(&ifibss->timer, 376 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 377 378 scan_width = cfg80211_chandef_to_scan_width(&chandef); 379 bss = cfg80211_inform_bss_width_frame(local->hw.wiphy, chan, 380 scan_width, mgmt, 381 presp->head_len, 0, GFP_KERNEL); 382 cfg80211_put_bss(local->hw.wiphy, bss); 383 netif_carrier_on(sdata->dev); 384 cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL); 385 } 386 387 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 388 struct ieee80211_bss *bss) 389 { 390 struct cfg80211_bss *cbss = 391 container_of((void *)bss, struct cfg80211_bss, priv); 392 struct ieee80211_supported_band *sband; 393 struct cfg80211_chan_def chandef; 394 u32 basic_rates; 395 int i, j; 396 u16 beacon_int = cbss->beacon_interval; 397 const struct cfg80211_bss_ies *ies; 398 enum nl80211_channel_type chan_type; 399 u64 tsf; 400 u32 rate_flags; 401 int shift; 402 403 sdata_assert_lock(sdata); 404 405 if (beacon_int < 10) 406 beacon_int = 10; 407 408 switch (sdata->u.ibss.chandef.width) { 409 case NL80211_CHAN_WIDTH_20_NOHT: 410 case NL80211_CHAN_WIDTH_20: 411 case NL80211_CHAN_WIDTH_40: 412 chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef); 413 cfg80211_chandef_create(&chandef, cbss->channel, chan_type); 414 break; 415 case NL80211_CHAN_WIDTH_5: 416 case NL80211_CHAN_WIDTH_10: 417 cfg80211_chandef_create(&chandef, cbss->channel, 418 NL80211_CHAN_WIDTH_20_NOHT); 419 chandef.width = sdata->u.ibss.chandef.width; 420 break; 421 default: 422 /* fall back to 20 MHz for unsupported modes */ 423 cfg80211_chandef_create(&chandef, cbss->channel, 424 NL80211_CHAN_WIDTH_20_NOHT); 425 break; 426 } 427 428 sband = sdata->local->hw.wiphy->bands[cbss->channel->band]; 429 rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef); 430 shift = ieee80211_vif_get_shift(&sdata->vif); 431 432 basic_rates = 0; 433 434 for (i = 0; i < bss->supp_rates_len; i++) { 435 int rate = bss->supp_rates[i] & 0x7f; 436 bool is_basic = !!(bss->supp_rates[i] & 0x80); 437 438 for (j = 0; j < sband->n_bitrates; j++) { 439 int brate; 440 if ((rate_flags & sband->bitrates[j].flags) 441 != rate_flags) 442 continue; 443 444 brate = DIV_ROUND_UP(sband->bitrates[j].bitrate, 445 5 * (1 << shift)); 446 if (brate == rate) { 447 if (is_basic) 448 basic_rates |= BIT(j); 449 break; 450 } 451 } 452 } 453 454 rcu_read_lock(); 455 ies = rcu_dereference(cbss->ies); 456 tsf = ies->tsf; 457 rcu_read_unlock(); 458 459 __ieee80211_sta_join_ibss(sdata, cbss->bssid, 460 beacon_int, 461 &chandef, 462 basic_rates, 463 cbss->capability, 464 tsf, false); 465 } 466 467 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata, 468 struct cfg80211_csa_settings *csa_settings) 469 { 470 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 471 struct beacon_data *presp, *old_presp; 472 struct cfg80211_bss *cbss; 473 const struct cfg80211_bss_ies *ies; 474 u16 capability; 475 u64 tsf; 476 int ret = 0; 477 478 sdata_assert_lock(sdata); 479 480 capability = WLAN_CAPABILITY_IBSS; 481 482 if (ifibss->privacy) 483 capability |= WLAN_CAPABILITY_PRIVACY; 484 485 cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan, 486 ifibss->bssid, ifibss->ssid, 487 ifibss->ssid_len, WLAN_CAPABILITY_IBSS | 488 WLAN_CAPABILITY_PRIVACY, 489 capability); 490 491 if (WARN_ON(!cbss)) { 492 ret = -EINVAL; 493 goto out; 494 } 495 496 rcu_read_lock(); 497 ies = rcu_dereference(cbss->ies); 498 tsf = ies->tsf; 499 rcu_read_unlock(); 500 cfg80211_put_bss(sdata->local->hw.wiphy, cbss); 501 502 old_presp = rcu_dereference_protected(ifibss->presp, 503 lockdep_is_held(&sdata->wdev.mtx)); 504 505 presp = ieee80211_ibss_build_presp(sdata, 506 sdata->vif.bss_conf.beacon_int, 507 sdata->vif.bss_conf.basic_rates, 508 capability, tsf, &ifibss->chandef, 509 NULL, csa_settings); 510 if (!presp) { 511 ret = -ENOMEM; 512 goto out; 513 } 514 515 rcu_assign_pointer(ifibss->presp, presp); 516 if (old_presp) 517 kfree_rcu(old_presp, rcu_head); 518 519 /* it might not send the beacon for a while. send an action frame 520 * immediately to announce the channel switch. 521 */ 522 if (csa_settings) 523 ieee80211_send_action_csa(sdata, csa_settings); 524 525 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON); 526 out: 527 return ret; 528 } 529 530 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata) 531 { 532 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 533 struct cfg80211_bss *cbss; 534 int err; 535 u16 capability; 536 537 sdata_lock(sdata); 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->local->csa_chandef.chan; 554 cfg80211_put_bss(sdata->local->hw.wiphy, cbss); 555 } 556 } 557 558 ifibss->chandef = sdata->local->csa_chandef; 559 560 /* generate the beacon */ 561 err = ieee80211_ibss_csa_beacon(sdata, NULL); 562 sdata_unlock(sdata); 563 if (err < 0) 564 return err; 565 566 return 0; 567 } 568 569 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata) 570 { 571 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 572 573 cancel_work_sync(&ifibss->csa_connection_drop_work); 574 } 575 576 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta) 577 __acquires(RCU) 578 { 579 struct ieee80211_sub_if_data *sdata = sta->sdata; 580 u8 addr[ETH_ALEN]; 581 582 memcpy(addr, sta->sta.addr, ETH_ALEN); 583 584 ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr); 585 586 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH); 587 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC); 588 /* authorize the station only if the network is not RSN protected. If 589 * not wait for the userspace to authorize it */ 590 if (!sta->sdata->u.ibss.control_port) 591 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED); 592 593 rate_control_rate_init(sta); 594 595 /* If it fails, maybe we raced another insertion? */ 596 if (sta_info_insert_rcu(sta)) 597 return sta_info_get(sdata, addr); 598 return sta; 599 } 600 601 static struct sta_info * 602 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid, 603 const u8 *addr, u32 supp_rates) 604 __acquires(RCU) 605 { 606 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 607 struct ieee80211_local *local = sdata->local; 608 struct sta_info *sta; 609 struct ieee80211_chanctx_conf *chanctx_conf; 610 struct ieee80211_supported_band *sband; 611 enum nl80211_bss_scan_width scan_width; 612 int band; 613 614 /* 615 * XXX: Consider removing the least recently used entry and 616 * allow new one to be added. 617 */ 618 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 619 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n", 620 sdata->name, addr); 621 rcu_read_lock(); 622 return NULL; 623 } 624 625 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) { 626 rcu_read_lock(); 627 return NULL; 628 } 629 630 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) { 631 rcu_read_lock(); 632 return NULL; 633 } 634 635 rcu_read_lock(); 636 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); 637 if (WARN_ON_ONCE(!chanctx_conf)) 638 return NULL; 639 band = chanctx_conf->def.chan->band; 640 scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def); 641 rcu_read_unlock(); 642 643 sta = sta_info_alloc(sdata, addr, GFP_KERNEL); 644 if (!sta) { 645 rcu_read_lock(); 646 return NULL; 647 } 648 649 sta->last_rx = jiffies; 650 651 /* make sure mandatory rates are always added */ 652 sband = local->hw.wiphy->bands[band]; 653 sta->sta.supp_rates[band] = supp_rates | 654 ieee80211_mandatory_rates(sband, scan_width); 655 656 return ieee80211_ibss_finish_sta(sta); 657 } 658 659 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata) 660 { 661 struct ieee80211_local *local = sdata->local; 662 int active = 0; 663 struct sta_info *sta; 664 665 sdata_assert_lock(sdata); 666 667 rcu_read_lock(); 668 669 list_for_each_entry_rcu(sta, &local->sta_list, list) { 670 if (sta->sdata == sdata && 671 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL, 672 jiffies)) { 673 active++; 674 break; 675 } 676 } 677 678 rcu_read_unlock(); 679 680 return active; 681 } 682 683 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata) 684 { 685 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 686 struct ieee80211_local *local = sdata->local; 687 struct cfg80211_bss *cbss; 688 struct beacon_data *presp; 689 struct sta_info *sta; 690 int active_ibss; 691 u16 capability; 692 693 active_ibss = ieee80211_sta_active_ibss(sdata); 694 695 if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) { 696 capability = WLAN_CAPABILITY_IBSS; 697 698 if (ifibss->privacy) 699 capability |= WLAN_CAPABILITY_PRIVACY; 700 701 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan, 702 ifibss->bssid, ifibss->ssid, 703 ifibss->ssid_len, WLAN_CAPABILITY_IBSS | 704 WLAN_CAPABILITY_PRIVACY, 705 capability); 706 707 if (cbss) { 708 cfg80211_unlink_bss(local->hw.wiphy, cbss); 709 cfg80211_put_bss(sdata->local->hw.wiphy, cbss); 710 } 711 } 712 713 ifibss->state = IEEE80211_IBSS_MLME_SEARCH; 714 715 sta_info_flush(sdata); 716 717 spin_lock_bh(&ifibss->incomplete_lock); 718 while (!list_empty(&ifibss->incomplete_stations)) { 719 sta = list_first_entry(&ifibss->incomplete_stations, 720 struct sta_info, list); 721 list_del(&sta->list); 722 spin_unlock_bh(&ifibss->incomplete_lock); 723 724 sta_info_free(local, sta); 725 spin_lock_bh(&ifibss->incomplete_lock); 726 } 727 spin_unlock_bh(&ifibss->incomplete_lock); 728 729 netif_carrier_off(sdata->dev); 730 731 sdata->vif.bss_conf.ibss_joined = false; 732 sdata->vif.bss_conf.ibss_creator = false; 733 sdata->vif.bss_conf.enable_beacon = false; 734 sdata->vif.bss_conf.ssid_len = 0; 735 736 /* remove beacon */ 737 presp = rcu_dereference_protected(ifibss->presp, 738 lockdep_is_held(&sdata->wdev.mtx)); 739 RCU_INIT_POINTER(sdata->u.ibss.presp, NULL); 740 if (presp) 741 kfree_rcu(presp, rcu_head); 742 743 clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state); 744 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED | 745 BSS_CHANGED_IBSS); 746 drv_leave_ibss(local, sdata); 747 ieee80211_vif_release_channel(sdata); 748 } 749 750 static void ieee80211_csa_connection_drop_work(struct work_struct *work) 751 { 752 struct ieee80211_sub_if_data *sdata = 753 container_of(work, struct ieee80211_sub_if_data, 754 u.ibss.csa_connection_drop_work); 755 756 ieee80211_ibss_disconnect(sdata); 757 synchronize_rcu(); 758 skb_queue_purge(&sdata->skb_queue); 759 760 /* trigger a scan to find another IBSS network to join */ 761 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 762 } 763 764 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata) 765 { 766 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 767 int err; 768 769 /* if the current channel is a DFS channel, mark the channel as 770 * unavailable. 771 */ 772 err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy, 773 &ifibss->chandef); 774 if (err > 0) 775 cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef, 776 GFP_ATOMIC); 777 } 778 779 static bool 780 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata, 781 struct ieee802_11_elems *elems, 782 bool beacon) 783 { 784 struct cfg80211_csa_settings params; 785 struct ieee80211_csa_ie csa_ie; 786 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 787 struct ieee80211_chanctx_conf *chanctx_conf; 788 struct ieee80211_chanctx *chanctx; 789 enum nl80211_channel_type ch_type; 790 int err, num_chanctx; 791 u32 sta_flags; 792 793 if (sdata->vif.csa_active) 794 return true; 795 796 if (!sdata->vif.bss_conf.ibss_joined) 797 return false; 798 799 sta_flags = IEEE80211_STA_DISABLE_VHT; 800 switch (ifibss->chandef.width) { 801 case NL80211_CHAN_WIDTH_5: 802 case NL80211_CHAN_WIDTH_10: 803 case NL80211_CHAN_WIDTH_20_NOHT: 804 sta_flags |= IEEE80211_STA_DISABLE_HT; 805 /* fall through */ 806 case NL80211_CHAN_WIDTH_20: 807 sta_flags |= IEEE80211_STA_DISABLE_40MHZ; 808 break; 809 default: 810 break; 811 } 812 813 memset(¶ms, 0, sizeof(params)); 814 memset(&csa_ie, 0, sizeof(csa_ie)); 815 err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon, 816 ifibss->chandef.chan->band, 817 sta_flags, ifibss->bssid, &csa_ie); 818 /* can't switch to destination channel, fail */ 819 if (err < 0) 820 goto disconnect; 821 822 /* did not contain a CSA */ 823 if (err) 824 return false; 825 826 /* channel switch is not supported, disconnect */ 827 if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH)) 828 goto disconnect; 829 830 params.count = csa_ie.count; 831 params.chandef = csa_ie.chandef; 832 833 if (ifibss->chandef.chan->band != params.chandef.chan->band) 834 goto disconnect; 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 rcu_read_lock(); 892 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); 893 if (!chanctx_conf) { 894 rcu_read_unlock(); 895 goto disconnect; 896 } 897 898 /* don't handle for multi-VIF cases */ 899 chanctx = container_of(chanctx_conf, struct ieee80211_chanctx, conf); 900 if (chanctx->refcount > 1) { 901 rcu_read_unlock(); 902 goto disconnect; 903 } 904 num_chanctx = 0; 905 list_for_each_entry_rcu(chanctx, &sdata->local->chanctx_list, list) 906 num_chanctx++; 907 908 if (num_chanctx > 1) { 909 rcu_read_unlock(); 910 goto disconnect; 911 } 912 rcu_read_unlock(); 913 914 /* all checks done, now perform the channel switch. */ 915 ibss_dbg(sdata, 916 "received channel switch announcement to go to channel %d MHz\n", 917 params.chandef.chan->center_freq); 918 919 params.block_tx = !!csa_ie.mode; 920 921 ieee80211_ibss_csa_beacon(sdata, ¶ms); 922 sdata->csa_radar_required = params.radar_required; 923 924 if (params.block_tx) 925 ieee80211_stop_queues_by_reason(&sdata->local->hw, 926 IEEE80211_MAX_QUEUE_MAP, 927 IEEE80211_QUEUE_STOP_REASON_CSA); 928 929 sdata->local->csa_chandef = params.chandef; 930 sdata->vif.csa_active = true; 931 932 ieee80211_bss_info_change_notify(sdata, err); 933 drv_channel_switch_beacon(sdata, ¶ms.chandef); 934 935 ieee80211_ibss_csa_mark_radar(sdata); 936 937 return true; 938 disconnect: 939 ibss_dbg(sdata, "Can't handle channel switch, disconnect\n"); 940 ieee80211_queue_work(&sdata->local->hw, 941 &ifibss->csa_connection_drop_work); 942 943 ieee80211_ibss_csa_mark_radar(sdata); 944 945 return true; 946 } 947 948 static void 949 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata, 950 struct ieee80211_mgmt *mgmt, size_t len, 951 struct ieee80211_rx_status *rx_status, 952 struct ieee802_11_elems *elems) 953 { 954 int required_len; 955 956 if (len < IEEE80211_MIN_ACTION_SIZE + 1) 957 return; 958 959 /* CSA is the only action we handle for now */ 960 if (mgmt->u.action.u.measurement.action_code != 961 WLAN_ACTION_SPCT_CHL_SWITCH) 962 return; 963 964 required_len = IEEE80211_MIN_ACTION_SIZE + 965 sizeof(mgmt->u.action.u.chan_switch); 966 if (len < required_len) 967 return; 968 969 ieee80211_ibss_process_chanswitch(sdata, elems, false); 970 } 971 972 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata, 973 struct ieee80211_mgmt *mgmt, 974 size_t len) 975 { 976 u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code); 977 978 if (len < IEEE80211_DEAUTH_FRAME_LEN) 979 return; 980 981 ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n", 982 mgmt->sa, mgmt->da, mgmt->bssid, reason); 983 sta_info_destroy_addr(sdata, mgmt->sa); 984 } 985 986 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata, 987 struct ieee80211_mgmt *mgmt, 988 size_t len) 989 { 990 u16 auth_alg, auth_transaction; 991 992 sdata_assert_lock(sdata); 993 994 if (len < 24 + 6) 995 return; 996 997 auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg); 998 auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction); 999 1000 ibss_dbg(sdata, 1001 "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n", 1002 mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction); 1003 1004 if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1) 1005 return; 1006 1007 /* 1008 * IEEE 802.11 standard does not require authentication in IBSS 1009 * networks and most implementations do not seem to use it. 1010 * However, try to reply to authentication attempts if someone 1011 * has actually implemented this. 1012 */ 1013 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0, 1014 mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0); 1015 } 1016 1017 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, 1018 struct ieee80211_mgmt *mgmt, size_t len, 1019 struct ieee80211_rx_status *rx_status, 1020 struct ieee802_11_elems *elems) 1021 { 1022 struct ieee80211_local *local = sdata->local; 1023 int freq; 1024 struct cfg80211_bss *cbss; 1025 struct ieee80211_bss *bss; 1026 struct sta_info *sta; 1027 struct ieee80211_channel *channel; 1028 u64 beacon_timestamp, rx_timestamp; 1029 u32 supp_rates = 0; 1030 enum ieee80211_band band = rx_status->band; 1031 enum nl80211_bss_scan_width scan_width; 1032 struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band]; 1033 bool rates_updated = false; 1034 1035 if (elems->ds_params) 1036 freq = ieee80211_channel_to_frequency(elems->ds_params[0], 1037 band); 1038 else 1039 freq = rx_status->freq; 1040 1041 channel = ieee80211_get_channel(local->hw.wiphy, freq); 1042 1043 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 1044 return; 1045 1046 if (sdata->vif.type == NL80211_IFTYPE_ADHOC && 1047 ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) { 1048 1049 rcu_read_lock(); 1050 sta = sta_info_get(sdata, mgmt->sa); 1051 1052 if (elems->supp_rates) { 1053 supp_rates = ieee80211_sta_get_rates(sdata, elems, 1054 band, NULL); 1055 if (sta) { 1056 u32 prev_rates; 1057 1058 prev_rates = sta->sta.supp_rates[band]; 1059 /* make sure mandatory rates are always added */ 1060 scan_width = NL80211_BSS_CHAN_WIDTH_20; 1061 if (rx_status->flag & RX_FLAG_5MHZ) 1062 scan_width = NL80211_BSS_CHAN_WIDTH_5; 1063 if (rx_status->flag & RX_FLAG_10MHZ) 1064 scan_width = NL80211_BSS_CHAN_WIDTH_10; 1065 1066 sta->sta.supp_rates[band] = supp_rates | 1067 ieee80211_mandatory_rates(sband, 1068 scan_width); 1069 if (sta->sta.supp_rates[band] != prev_rates) { 1070 ibss_dbg(sdata, 1071 "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n", 1072 sta->sta.addr, prev_rates, 1073 sta->sta.supp_rates[band]); 1074 rates_updated = true; 1075 } 1076 } else { 1077 rcu_read_unlock(); 1078 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, 1079 mgmt->sa, supp_rates); 1080 } 1081 } 1082 1083 if (sta && elems->wmm_info) 1084 set_sta_flag(sta, WLAN_STA_WME); 1085 1086 if (sta && elems->ht_operation && elems->ht_cap_elem && 1087 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT && 1088 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 && 1089 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) { 1090 /* we both use HT */ 1091 struct ieee80211_ht_cap htcap_ie; 1092 struct cfg80211_chan_def chandef; 1093 1094 ieee80211_ht_oper_to_chandef(channel, 1095 elems->ht_operation, 1096 &chandef); 1097 1098 memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie)); 1099 1100 /* 1101 * fall back to HT20 if we don't use or use 1102 * the other extension channel 1103 */ 1104 if (chandef.center_freq1 != 1105 sdata->u.ibss.chandef.center_freq1) 1106 htcap_ie.cap_info &= 1107 cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40); 1108 1109 rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap( 1110 sdata, sband, &htcap_ie, sta); 1111 } 1112 1113 if (sta && rates_updated) { 1114 drv_sta_rc_update(local, sdata, &sta->sta, 1115 IEEE80211_RC_SUPP_RATES_CHANGED); 1116 rate_control_rate_init(sta); 1117 } 1118 1119 rcu_read_unlock(); 1120 } 1121 1122 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems, 1123 channel); 1124 if (!bss) 1125 return; 1126 1127 cbss = container_of((void *)bss, struct cfg80211_bss, priv); 1128 1129 /* same for beacon and probe response */ 1130 beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp); 1131 1132 /* check if we need to merge IBSS */ 1133 1134 /* not an IBSS */ 1135 if (!(cbss->capability & WLAN_CAPABILITY_IBSS)) 1136 goto put_bss; 1137 1138 /* different channel */ 1139 if (sdata->u.ibss.fixed_channel && 1140 sdata->u.ibss.chandef.chan != cbss->channel) 1141 goto put_bss; 1142 1143 /* different SSID */ 1144 if (elems->ssid_len != sdata->u.ibss.ssid_len || 1145 memcmp(elems->ssid, sdata->u.ibss.ssid, 1146 sdata->u.ibss.ssid_len)) 1147 goto put_bss; 1148 1149 /* process channel switch */ 1150 if (ieee80211_ibss_process_chanswitch(sdata, elems, true)) 1151 goto put_bss; 1152 1153 /* same BSSID */ 1154 if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid)) 1155 goto put_bss; 1156 1157 /* we use a fixed BSSID */ 1158 if (sdata->u.ibss.fixed_bssid) 1159 goto put_bss; 1160 1161 if (ieee80211_have_rx_timestamp(rx_status)) { 1162 /* time when timestamp field was received */ 1163 rx_timestamp = 1164 ieee80211_calculate_rx_timestamp(local, rx_status, 1165 len + FCS_LEN, 24); 1166 } else { 1167 /* 1168 * second best option: get current TSF 1169 * (will return -1 if not supported) 1170 */ 1171 rx_timestamp = drv_get_tsf(local, sdata); 1172 } 1173 1174 ibss_dbg(sdata, 1175 "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n", 1176 mgmt->sa, mgmt->bssid, 1177 (unsigned long long)rx_timestamp, 1178 (unsigned long long)beacon_timestamp, 1179 (unsigned long long)(rx_timestamp - beacon_timestamp), 1180 jiffies); 1181 1182 if (beacon_timestamp > rx_timestamp) { 1183 ibss_dbg(sdata, 1184 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n", 1185 mgmt->bssid); 1186 ieee80211_sta_join_ibss(sdata, bss); 1187 supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL); 1188 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 1189 supp_rates); 1190 rcu_read_unlock(); 1191 } 1192 1193 put_bss: 1194 ieee80211_rx_bss_put(local, bss); 1195 } 1196 1197 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata, 1198 const u8 *bssid, const u8 *addr, 1199 u32 supp_rates) 1200 { 1201 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1202 struct ieee80211_local *local = sdata->local; 1203 struct sta_info *sta; 1204 struct ieee80211_chanctx_conf *chanctx_conf; 1205 struct ieee80211_supported_band *sband; 1206 enum nl80211_bss_scan_width scan_width; 1207 int band; 1208 1209 /* 1210 * XXX: Consider removing the least recently used entry and 1211 * allow new one to be added. 1212 */ 1213 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 1214 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n", 1215 sdata->name, addr); 1216 return; 1217 } 1218 1219 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) 1220 return; 1221 1222 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) 1223 return; 1224 1225 rcu_read_lock(); 1226 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); 1227 if (WARN_ON_ONCE(!chanctx_conf)) { 1228 rcu_read_unlock(); 1229 return; 1230 } 1231 band = chanctx_conf->def.chan->band; 1232 scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def); 1233 rcu_read_unlock(); 1234 1235 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC); 1236 if (!sta) 1237 return; 1238 1239 sta->last_rx = jiffies; 1240 1241 /* make sure mandatory rates are always added */ 1242 sband = local->hw.wiphy->bands[band]; 1243 sta->sta.supp_rates[band] = supp_rates | 1244 ieee80211_mandatory_rates(sband, scan_width); 1245 1246 spin_lock(&ifibss->incomplete_lock); 1247 list_add(&sta->list, &ifibss->incomplete_stations); 1248 spin_unlock(&ifibss->incomplete_lock); 1249 ieee80211_queue_work(&local->hw, &sdata->work); 1250 } 1251 1252 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata) 1253 { 1254 struct ieee80211_local *local = sdata->local; 1255 struct sta_info *sta, *tmp; 1256 unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT; 1257 unsigned long exp_rsn_time = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT; 1258 1259 mutex_lock(&local->sta_mtx); 1260 1261 list_for_each_entry_safe(sta, tmp, &local->sta_list, list) { 1262 if (sdata != sta->sdata) 1263 continue; 1264 1265 if (time_after(jiffies, sta->last_rx + exp_time) || 1266 (time_after(jiffies, sta->last_rx + exp_rsn_time) && 1267 sta->sta_state != IEEE80211_STA_AUTHORIZED)) { 1268 sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n", 1269 sta->sta_state != IEEE80211_STA_AUTHORIZED ? 1270 "not authorized " : "", sta->sta.addr); 1271 1272 WARN_ON(__sta_info_destroy(sta)); 1273 } 1274 } 1275 1276 mutex_unlock(&local->sta_mtx); 1277 } 1278 1279 /* 1280 * This function is called with state == IEEE80211_IBSS_MLME_JOINED 1281 */ 1282 1283 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata) 1284 { 1285 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1286 enum nl80211_bss_scan_width scan_width; 1287 1288 sdata_assert_lock(sdata); 1289 1290 mod_timer(&ifibss->timer, 1291 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 1292 1293 ieee80211_ibss_sta_expire(sdata); 1294 1295 if (time_before(jiffies, ifibss->last_scan_completed + 1296 IEEE80211_IBSS_MERGE_INTERVAL)) 1297 return; 1298 1299 if (ieee80211_sta_active_ibss(sdata)) 1300 return; 1301 1302 if (ifibss->fixed_channel) 1303 return; 1304 1305 sdata_info(sdata, 1306 "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n"); 1307 1308 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef); 1309 ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len, 1310 NULL, scan_width); 1311 } 1312 1313 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata) 1314 { 1315 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1316 u8 bssid[ETH_ALEN]; 1317 u16 capability; 1318 int i; 1319 1320 sdata_assert_lock(sdata); 1321 1322 if (ifibss->fixed_bssid) { 1323 memcpy(bssid, ifibss->bssid, ETH_ALEN); 1324 } else { 1325 /* Generate random, not broadcast, locally administered BSSID. Mix in 1326 * own MAC address to make sure that devices that do not have proper 1327 * random number generator get different BSSID. */ 1328 get_random_bytes(bssid, ETH_ALEN); 1329 for (i = 0; i < ETH_ALEN; i++) 1330 bssid[i] ^= sdata->vif.addr[i]; 1331 bssid[0] &= ~0x01; 1332 bssid[0] |= 0x02; 1333 } 1334 1335 sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid); 1336 1337 capability = WLAN_CAPABILITY_IBSS; 1338 1339 if (ifibss->privacy) 1340 capability |= WLAN_CAPABILITY_PRIVACY; 1341 else 1342 sdata->drop_unencrypted = 0; 1343 1344 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int, 1345 &ifibss->chandef, ifibss->basic_rates, 1346 capability, 0, true); 1347 } 1348 1349 /* 1350 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH 1351 */ 1352 1353 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata) 1354 { 1355 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1356 struct ieee80211_local *local = sdata->local; 1357 struct cfg80211_bss *cbss; 1358 struct ieee80211_channel *chan = NULL; 1359 const u8 *bssid = NULL; 1360 enum nl80211_bss_scan_width scan_width; 1361 int active_ibss; 1362 u16 capability; 1363 1364 sdata_assert_lock(sdata); 1365 1366 active_ibss = ieee80211_sta_active_ibss(sdata); 1367 ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss); 1368 1369 if (active_ibss) 1370 return; 1371 1372 capability = WLAN_CAPABILITY_IBSS; 1373 if (ifibss->privacy) 1374 capability |= WLAN_CAPABILITY_PRIVACY; 1375 if (ifibss->fixed_bssid) 1376 bssid = ifibss->bssid; 1377 if (ifibss->fixed_channel) 1378 chan = ifibss->chandef.chan; 1379 if (!is_zero_ether_addr(ifibss->bssid)) 1380 bssid = ifibss->bssid; 1381 cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid, 1382 ifibss->ssid, ifibss->ssid_len, 1383 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY, 1384 capability); 1385 1386 if (cbss) { 1387 struct ieee80211_bss *bss; 1388 1389 bss = (void *)cbss->priv; 1390 ibss_dbg(sdata, 1391 "sta_find_ibss: selected %pM current %pM\n", 1392 cbss->bssid, ifibss->bssid); 1393 sdata_info(sdata, 1394 "Selected IBSS BSSID %pM based on configured SSID\n", 1395 cbss->bssid); 1396 1397 ieee80211_sta_join_ibss(sdata, bss); 1398 ieee80211_rx_bss_put(local, bss); 1399 return; 1400 } 1401 1402 /* if a fixed bssid and a fixed freq have been provided create the IBSS 1403 * directly and do not waste time scanning 1404 */ 1405 if (ifibss->fixed_bssid && ifibss->fixed_channel) { 1406 sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n", 1407 bssid); 1408 ieee80211_sta_create_ibss(sdata); 1409 return; 1410 } 1411 1412 1413 ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n"); 1414 1415 /* Selected IBSS not found in current scan results - try to scan */ 1416 if (time_after(jiffies, ifibss->last_scan_completed + 1417 IEEE80211_SCAN_INTERVAL)) { 1418 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n"); 1419 1420 scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef); 1421 ieee80211_request_ibss_scan(sdata, ifibss->ssid, 1422 ifibss->ssid_len, chan, 1423 scan_width); 1424 } else { 1425 int interval = IEEE80211_SCAN_INTERVAL; 1426 1427 if (time_after(jiffies, ifibss->ibss_join_req + 1428 IEEE80211_IBSS_JOIN_TIMEOUT)) 1429 ieee80211_sta_create_ibss(sdata); 1430 1431 mod_timer(&ifibss->timer, 1432 round_jiffies(jiffies + interval)); 1433 } 1434 } 1435 1436 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata, 1437 struct sk_buff *req) 1438 { 1439 struct ieee80211_mgmt *mgmt = (void *)req->data; 1440 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1441 struct ieee80211_local *local = sdata->local; 1442 int tx_last_beacon, len = req->len; 1443 struct sk_buff *skb; 1444 struct beacon_data *presp; 1445 u8 *pos, *end; 1446 1447 sdata_assert_lock(sdata); 1448 1449 presp = rcu_dereference_protected(ifibss->presp, 1450 lockdep_is_held(&sdata->wdev.mtx)); 1451 1452 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED || 1453 len < 24 + 2 || !presp) 1454 return; 1455 1456 tx_last_beacon = drv_tx_last_beacon(local); 1457 1458 ibss_dbg(sdata, 1459 "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n", 1460 mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon); 1461 1462 if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da)) 1463 return; 1464 1465 if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) && 1466 !is_broadcast_ether_addr(mgmt->bssid)) 1467 return; 1468 1469 end = ((u8 *) mgmt) + len; 1470 pos = mgmt->u.probe_req.variable; 1471 if (pos[0] != WLAN_EID_SSID || 1472 pos + 2 + pos[1] > end) { 1473 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n", 1474 mgmt->sa); 1475 return; 1476 } 1477 if (pos[1] != 0 && 1478 (pos[1] != ifibss->ssid_len || 1479 memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) { 1480 /* Ignore ProbeReq for foreign SSID */ 1481 return; 1482 } 1483 1484 /* Reply with ProbeResp */ 1485 skb = dev_alloc_skb(local->tx_headroom + presp->head_len); 1486 if (!skb) 1487 return; 1488 1489 skb_reserve(skb, local->tx_headroom); 1490 memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len); 1491 1492 memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN); 1493 ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa); 1494 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 1495 ieee80211_tx_skb(sdata, skb); 1496 } 1497 1498 static 1499 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata, 1500 struct ieee80211_mgmt *mgmt, size_t len, 1501 struct ieee80211_rx_status *rx_status) 1502 { 1503 size_t baselen; 1504 struct ieee802_11_elems elems; 1505 1506 BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) != 1507 offsetof(typeof(mgmt->u.beacon), variable)); 1508 1509 /* 1510 * either beacon or probe_resp but the variable field is at the 1511 * same offset 1512 */ 1513 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt; 1514 if (baselen > len) 1515 return; 1516 1517 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen, 1518 false, &elems); 1519 1520 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems); 1521 } 1522 1523 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata, 1524 struct sk_buff *skb) 1525 { 1526 struct ieee80211_rx_status *rx_status; 1527 struct ieee80211_mgmt *mgmt; 1528 u16 fc; 1529 struct ieee802_11_elems elems; 1530 int ies_len; 1531 1532 rx_status = IEEE80211_SKB_RXCB(skb); 1533 mgmt = (struct ieee80211_mgmt *) skb->data; 1534 fc = le16_to_cpu(mgmt->frame_control); 1535 1536 sdata_lock(sdata); 1537 1538 if (!sdata->u.ibss.ssid_len) 1539 goto mgmt_out; /* not ready to merge yet */ 1540 1541 switch (fc & IEEE80211_FCTL_STYPE) { 1542 case IEEE80211_STYPE_PROBE_REQ: 1543 ieee80211_rx_mgmt_probe_req(sdata, skb); 1544 break; 1545 case IEEE80211_STYPE_PROBE_RESP: 1546 case IEEE80211_STYPE_BEACON: 1547 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len, 1548 rx_status); 1549 break; 1550 case IEEE80211_STYPE_AUTH: 1551 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len); 1552 break; 1553 case IEEE80211_STYPE_DEAUTH: 1554 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len); 1555 break; 1556 case IEEE80211_STYPE_ACTION: 1557 switch (mgmt->u.action.category) { 1558 case WLAN_CATEGORY_SPECTRUM_MGMT: 1559 ies_len = skb->len - 1560 offsetof(struct ieee80211_mgmt, 1561 u.action.u.chan_switch.variable); 1562 1563 if (ies_len < 0) 1564 break; 1565 1566 ieee802_11_parse_elems( 1567 mgmt->u.action.u.chan_switch.variable, 1568 ies_len, true, &elems); 1569 1570 if (elems.parse_error) 1571 break; 1572 1573 ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len, 1574 rx_status, &elems); 1575 break; 1576 } 1577 } 1578 1579 mgmt_out: 1580 sdata_unlock(sdata); 1581 } 1582 1583 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata) 1584 { 1585 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1586 struct sta_info *sta; 1587 1588 sdata_lock(sdata); 1589 1590 /* 1591 * Work could be scheduled after scan or similar 1592 * when we aren't even joined (or trying) with a 1593 * network. 1594 */ 1595 if (!ifibss->ssid_len) 1596 goto out; 1597 1598 spin_lock_bh(&ifibss->incomplete_lock); 1599 while (!list_empty(&ifibss->incomplete_stations)) { 1600 sta = list_first_entry(&ifibss->incomplete_stations, 1601 struct sta_info, list); 1602 list_del(&sta->list); 1603 spin_unlock_bh(&ifibss->incomplete_lock); 1604 1605 ieee80211_ibss_finish_sta(sta); 1606 rcu_read_unlock(); 1607 spin_lock_bh(&ifibss->incomplete_lock); 1608 } 1609 spin_unlock_bh(&ifibss->incomplete_lock); 1610 1611 switch (ifibss->state) { 1612 case IEEE80211_IBSS_MLME_SEARCH: 1613 ieee80211_sta_find_ibss(sdata); 1614 break; 1615 case IEEE80211_IBSS_MLME_JOINED: 1616 ieee80211_sta_merge_ibss(sdata); 1617 break; 1618 default: 1619 WARN_ON(1); 1620 break; 1621 } 1622 1623 out: 1624 sdata_unlock(sdata); 1625 } 1626 1627 static void ieee80211_ibss_timer(unsigned long data) 1628 { 1629 struct ieee80211_sub_if_data *sdata = 1630 (struct ieee80211_sub_if_data *) data; 1631 1632 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 1633 } 1634 1635 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata) 1636 { 1637 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1638 1639 setup_timer(&ifibss->timer, ieee80211_ibss_timer, 1640 (unsigned long) sdata); 1641 INIT_LIST_HEAD(&ifibss->incomplete_stations); 1642 spin_lock_init(&ifibss->incomplete_lock); 1643 INIT_WORK(&ifibss->csa_connection_drop_work, 1644 ieee80211_csa_connection_drop_work); 1645 } 1646 1647 /* scan finished notification */ 1648 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local) 1649 { 1650 struct ieee80211_sub_if_data *sdata; 1651 1652 mutex_lock(&local->iflist_mtx); 1653 list_for_each_entry(sdata, &local->interfaces, list) { 1654 if (!ieee80211_sdata_running(sdata)) 1655 continue; 1656 if (sdata->vif.type != NL80211_IFTYPE_ADHOC) 1657 continue; 1658 sdata->u.ibss.last_scan_completed = jiffies; 1659 ieee80211_queue_work(&local->hw, &sdata->work); 1660 } 1661 mutex_unlock(&local->iflist_mtx); 1662 } 1663 1664 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata, 1665 struct cfg80211_ibss_params *params) 1666 { 1667 u32 changed = 0; 1668 u32 rate_flags; 1669 struct ieee80211_supported_band *sband; 1670 int i; 1671 1672 if (params->bssid) { 1673 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN); 1674 sdata->u.ibss.fixed_bssid = true; 1675 } else 1676 sdata->u.ibss.fixed_bssid = false; 1677 1678 sdata->u.ibss.privacy = params->privacy; 1679 sdata->u.ibss.control_port = params->control_port; 1680 sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs; 1681 sdata->u.ibss.basic_rates = params->basic_rates; 1682 1683 /* fix basic_rates if channel does not support these rates */ 1684 rate_flags = ieee80211_chandef_rate_flags(¶ms->chandef); 1685 sband = sdata->local->hw.wiphy->bands[params->chandef.chan->band]; 1686 for (i = 0; i < sband->n_bitrates; i++) { 1687 if ((rate_flags & sband->bitrates[i].flags) != rate_flags) 1688 sdata->u.ibss.basic_rates &= ~BIT(i); 1689 } 1690 memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate, 1691 sizeof(params->mcast_rate)); 1692 1693 sdata->vif.bss_conf.beacon_int = params->beacon_interval; 1694 1695 sdata->u.ibss.chandef = params->chandef; 1696 sdata->u.ibss.fixed_channel = params->channel_fixed; 1697 1698 if (params->ie) { 1699 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len, 1700 GFP_KERNEL); 1701 if (sdata->u.ibss.ie) 1702 sdata->u.ibss.ie_len = params->ie_len; 1703 } 1704 1705 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; 1706 sdata->u.ibss.ibss_join_req = jiffies; 1707 1708 memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len); 1709 sdata->u.ibss.ssid_len = params->ssid_len; 1710 1711 memcpy(&sdata->u.ibss.ht_capa, ¶ms->ht_capa, 1712 sizeof(sdata->u.ibss.ht_capa)); 1713 memcpy(&sdata->u.ibss.ht_capa_mask, ¶ms->ht_capa_mask, 1714 sizeof(sdata->u.ibss.ht_capa_mask)); 1715 1716 /* 1717 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is 1718 * reserved, but an HT STA shall protect HT transmissions as though 1719 * the HT Protection field were set to non-HT mixed mode. 1720 * 1721 * In an IBSS, the RIFS Mode field of the HT Operation element is 1722 * also reserved, but an HT STA shall operate as though this field 1723 * were set to 1. 1724 */ 1725 1726 sdata->vif.bss_conf.ht_operation_mode |= 1727 IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED 1728 | IEEE80211_HT_PARAM_RIFS_MODE; 1729 1730 changed |= BSS_CHANGED_HT; 1731 ieee80211_bss_info_change_notify(sdata, changed); 1732 1733 sdata->smps_mode = IEEE80211_SMPS_OFF; 1734 sdata->needed_rx_chains = sdata->local->rx_chains; 1735 1736 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 1737 1738 return 0; 1739 } 1740 1741 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata) 1742 { 1743 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1744 1745 ieee80211_ibss_disconnect(sdata); 1746 ifibss->ssid_len = 0; 1747 memset(ifibss->bssid, 0, ETH_ALEN); 1748 1749 /* remove beacon */ 1750 kfree(sdata->u.ibss.ie); 1751 1752 /* on the next join, re-program HT parameters */ 1753 memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa)); 1754 memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask)); 1755 1756 synchronize_rcu(); 1757 1758 skb_queue_purge(&sdata->skb_queue); 1759 1760 del_timer_sync(&sdata->u.ibss.timer); 1761 1762 return 0; 1763 } 1764