ibss.c revision 7bed20503f62ae9660c7b5cd6c3603960e422450
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 34#define IEEE80211_IBSS_MAX_STA_ENTRIES 128 35 36 37static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 38 const u8 *bssid, const int beacon_int, 39 struct ieee80211_channel *chan, 40 const u32 basic_rates, 41 const u16 capability, u64 tsf, 42 bool creator) 43{ 44 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 45 struct ieee80211_local *local = sdata->local; 46 int rates, i; 47 struct sk_buff *skb; 48 struct ieee80211_mgmt *mgmt; 49 u8 *pos; 50 struct ieee80211_supported_band *sband; 51 struct cfg80211_bss *bss; 52 u32 bss_change; 53 u8 supp_rates[IEEE80211_MAX_SUPP_RATES]; 54 enum nl80211_channel_type channel_type; 55 56 lockdep_assert_held(&ifibss->mtx); 57 58 /* Reset own TSF to allow time synchronization work. */ 59 drv_reset_tsf(local, sdata); 60 61 skb = ifibss->skb; 62 RCU_INIT_POINTER(ifibss->presp, NULL); 63 synchronize_rcu(); 64 skb->data = skb->head; 65 skb->len = 0; 66 skb_reset_tail_pointer(skb); 67 skb_reserve(skb, sdata->local->hw.extra_tx_headroom); 68 69 if (!ether_addr_equal(ifibss->bssid, bssid)) 70 sta_info_flush(sdata->local, sdata); 71 72 /* if merging, indicate to driver that we leave the old IBSS */ 73 if (sdata->vif.bss_conf.ibss_joined) { 74 sdata->vif.bss_conf.ibss_joined = false; 75 sdata->vif.bss_conf.ibss_creator = false; 76 netif_carrier_off(sdata->dev); 77 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IBSS); 78 } 79 80 sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0; 81 82 channel_type = ifibss->channel_type; 83 if (!cfg80211_can_beacon_sec_chan(local->hw.wiphy, chan, channel_type)) 84 channel_type = NL80211_CHAN_HT20; 85 86 ieee80211_vif_release_channel(sdata); 87 if (ieee80211_vif_use_channel(sdata, chan, channel_type, 88 ifibss->fixed_channel ? 89 IEEE80211_CHANCTX_SHARED : 90 IEEE80211_CHANCTX_EXCLUSIVE)) { 91 sdata_info(sdata, "Failed to join IBSS, no channel context\n"); 92 return; 93 } 94 95 memcpy(ifibss->bssid, bssid, ETH_ALEN); 96 97 sband = local->hw.wiphy->bands[chan->band]; 98 99 /* build supported rates array */ 100 pos = supp_rates; 101 for (i = 0; i < sband->n_bitrates; i++) { 102 int rate = sband->bitrates[i].bitrate; 103 u8 basic = 0; 104 if (basic_rates & BIT(i)) 105 basic = 0x80; 106 *pos++ = basic | (u8) (rate / 5); 107 } 108 109 /* Build IBSS probe response */ 110 mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon)); 111 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon)); 112 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 113 IEEE80211_STYPE_PROBE_RESP); 114 eth_broadcast_addr(mgmt->da); 115 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 116 memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN); 117 mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int); 118 mgmt->u.beacon.timestamp = cpu_to_le64(tsf); 119 mgmt->u.beacon.capab_info = cpu_to_le16(capability); 120 121 pos = skb_put(skb, 2 + ifibss->ssid_len); 122 *pos++ = WLAN_EID_SSID; 123 *pos++ = ifibss->ssid_len; 124 memcpy(pos, ifibss->ssid, ifibss->ssid_len); 125 126 rates = sband->n_bitrates; 127 if (rates > 8) 128 rates = 8; 129 pos = skb_put(skb, 2 + rates); 130 *pos++ = WLAN_EID_SUPP_RATES; 131 *pos++ = rates; 132 memcpy(pos, supp_rates, rates); 133 134 if (sband->band == IEEE80211_BAND_2GHZ) { 135 pos = skb_put(skb, 2 + 1); 136 *pos++ = WLAN_EID_DS_PARAMS; 137 *pos++ = 1; 138 *pos++ = ieee80211_frequency_to_channel(chan->center_freq); 139 } 140 141 pos = skb_put(skb, 2 + 2); 142 *pos++ = WLAN_EID_IBSS_PARAMS; 143 *pos++ = 2; 144 /* FIX: set ATIM window based on scan results */ 145 *pos++ = 0; 146 *pos++ = 0; 147 148 if (sband->n_bitrates > 8) { 149 rates = sband->n_bitrates - 8; 150 pos = skb_put(skb, 2 + rates); 151 *pos++ = WLAN_EID_EXT_SUPP_RATES; 152 *pos++ = rates; 153 memcpy(pos, &supp_rates[8], rates); 154 } 155 156 if (ifibss->ie_len) 157 memcpy(skb_put(skb, ifibss->ie_len), 158 ifibss->ie, ifibss->ie_len); 159 160 /* add HT capability and information IEs */ 161 if (channel_type && sband->ht_cap.ht_supported) { 162 pos = skb_put(skb, 4 + 163 sizeof(struct ieee80211_ht_cap) + 164 sizeof(struct ieee80211_ht_operation)); 165 pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap, 166 sband->ht_cap.cap); 167 /* 168 * Note: According to 802.11n-2009 9.13.3.1, HT Protection 169 * field and RIFS Mode are reserved in IBSS mode, therefore 170 * keep them at 0 171 */ 172 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap, 173 chan, channel_type, 0); 174 } 175 176 if (local->hw.queues >= IEEE80211_NUM_ACS) { 177 pos = skb_put(skb, 9); 178 *pos++ = WLAN_EID_VENDOR_SPECIFIC; 179 *pos++ = 7; /* len */ 180 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */ 181 *pos++ = 0x50; 182 *pos++ = 0xf2; 183 *pos++ = 2; /* WME */ 184 *pos++ = 0; /* WME info */ 185 *pos++ = 1; /* WME ver */ 186 *pos++ = 0; /* U-APSD no in use */ 187 } 188 189 rcu_assign_pointer(ifibss->presp, skb); 190 191 sdata->vif.bss_conf.beacon_int = beacon_int; 192 sdata->vif.bss_conf.basic_rates = basic_rates; 193 bss_change = BSS_CHANGED_BEACON_INT; 194 bss_change |= ieee80211_reset_erp_info(sdata); 195 bss_change |= BSS_CHANGED_BSSID; 196 bss_change |= BSS_CHANGED_BEACON; 197 bss_change |= BSS_CHANGED_BEACON_ENABLED; 198 bss_change |= BSS_CHANGED_BASIC_RATES; 199 bss_change |= BSS_CHANGED_HT; 200 bss_change |= BSS_CHANGED_IBSS; 201 sdata->vif.bss_conf.ibss_joined = true; 202 sdata->vif.bss_conf.ibss_creator = creator; 203 ieee80211_bss_info_change_notify(sdata, bss_change); 204 205 ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates); 206 207 ifibss->state = IEEE80211_IBSS_MLME_JOINED; 208 mod_timer(&ifibss->timer, 209 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 210 211 bss = cfg80211_inform_bss_frame(local->hw.wiphy, chan, 212 mgmt, skb->len, 0, GFP_KERNEL); 213 cfg80211_put_bss(bss); 214 netif_carrier_on(sdata->dev); 215 cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL); 216} 217 218static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 219 struct ieee80211_bss *bss) 220{ 221 struct cfg80211_bss *cbss = 222 container_of((void *)bss, struct cfg80211_bss, priv); 223 struct ieee80211_supported_band *sband; 224 u32 basic_rates; 225 int i, j; 226 u16 beacon_int = cbss->beacon_interval; 227 228 lockdep_assert_held(&sdata->u.ibss.mtx); 229 230 if (beacon_int < 10) 231 beacon_int = 10; 232 233 sband = sdata->local->hw.wiphy->bands[cbss->channel->band]; 234 235 basic_rates = 0; 236 237 for (i = 0; i < bss->supp_rates_len; i++) { 238 int rate = (bss->supp_rates[i] & 0x7f) * 5; 239 bool is_basic = !!(bss->supp_rates[i] & 0x80); 240 241 for (j = 0; j < sband->n_bitrates; j++) { 242 if (sband->bitrates[j].bitrate == rate) { 243 if (is_basic) 244 basic_rates |= BIT(j); 245 break; 246 } 247 } 248 } 249 250 __ieee80211_sta_join_ibss(sdata, cbss->bssid, 251 beacon_int, 252 cbss->channel, 253 basic_rates, 254 cbss->capability, 255 cbss->tsf, 256 false); 257} 258 259static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta, 260 bool auth) 261 __acquires(RCU) 262{ 263 struct ieee80211_sub_if_data *sdata = sta->sdata; 264 u8 addr[ETH_ALEN]; 265 266 memcpy(addr, sta->sta.addr, ETH_ALEN); 267 268 ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr); 269 270 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH); 271 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC); 272 /* authorize the station only if the network is not RSN protected. If 273 * not wait for the userspace to authorize it */ 274 if (!sta->sdata->u.ibss.control_port) 275 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED); 276 277 rate_control_rate_init(sta); 278 279 /* If it fails, maybe we raced another insertion? */ 280 if (sta_info_insert_rcu(sta)) 281 return sta_info_get(sdata, addr); 282 if (auth && !sdata->u.ibss.auth_frame_registrations) { 283 ibss_dbg(sdata, 284 "TX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=1)\n", 285 sdata->vif.addr, addr, sdata->u.ibss.bssid); 286 ieee80211_send_auth(sdata, 1, WLAN_AUTH_OPEN, 0, NULL, 0, 287 addr, sdata->u.ibss.bssid, NULL, 0, 0); 288 } 289 return sta; 290} 291 292static struct sta_info * 293ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, 294 const u8 *bssid, const u8 *addr, 295 u32 supp_rates, bool auth) 296 __acquires(RCU) 297{ 298 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 299 struct ieee80211_local *local = sdata->local; 300 struct sta_info *sta; 301 struct ieee80211_chanctx_conf *chanctx_conf; 302 int band; 303 304 /* 305 * XXX: Consider removing the least recently used entry and 306 * allow new one to be added. 307 */ 308 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 309 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n", 310 sdata->name, addr); 311 rcu_read_lock(); 312 return NULL; 313 } 314 315 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) { 316 rcu_read_lock(); 317 return NULL; 318 } 319 320 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) { 321 rcu_read_lock(); 322 return NULL; 323 } 324 325 rcu_read_lock(); 326 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); 327 if (WARN_ON_ONCE(!chanctx_conf)) 328 return NULL; 329 band = chanctx_conf->channel->band; 330 rcu_read_unlock(); 331 332 sta = sta_info_alloc(sdata, addr, GFP_KERNEL); 333 if (!sta) { 334 rcu_read_lock(); 335 return NULL; 336 } 337 338 sta->last_rx = jiffies; 339 340 /* make sure mandatory rates are always added */ 341 sta->sta.supp_rates[band] = supp_rates | 342 ieee80211_mandatory_rates(local, band); 343 344 return ieee80211_ibss_finish_sta(sta, auth); 345} 346 347static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata, 348 struct ieee80211_mgmt *mgmt, 349 size_t len) 350{ 351 u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code); 352 353 if (len < IEEE80211_DEAUTH_FRAME_LEN) 354 return; 355 356 ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n", 357 mgmt->sa, mgmt->da, mgmt->bssid, reason); 358 sta_info_destroy_addr(sdata, mgmt->sa); 359} 360 361static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata, 362 struct ieee80211_mgmt *mgmt, 363 size_t len) 364{ 365 u16 auth_alg, auth_transaction; 366 struct sta_info *sta; 367 u8 deauth_frame_buf[IEEE80211_DEAUTH_FRAME_LEN]; 368 369 lockdep_assert_held(&sdata->u.ibss.mtx); 370 371 if (len < 24 + 6) 372 return; 373 374 auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg); 375 auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction); 376 377 ibss_dbg(sdata, 378 "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n", 379 mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction); 380 381 if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1) 382 return; 383 384 sta_info_destroy_addr(sdata, mgmt->sa); 385 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 0, false); 386 rcu_read_unlock(); 387 388 /* 389 * if we have any problem in allocating the new station, we reply with a 390 * DEAUTH frame to tell the other end that we had a problem 391 */ 392 if (!sta) { 393 ieee80211_send_deauth_disassoc(sdata, sdata->u.ibss.bssid, 394 IEEE80211_STYPE_DEAUTH, 395 WLAN_REASON_UNSPECIFIED, true, 396 deauth_frame_buf); 397 return; 398 } 399 400 /* 401 * IEEE 802.11 standard does not require authentication in IBSS 402 * networks and most implementations do not seem to use it. 403 * However, try to reply to authentication attempts if someone 404 * has actually implemented this. 405 */ 406 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0, 407 mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0); 408} 409 410static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, 411 struct ieee80211_mgmt *mgmt, 412 size_t len, 413 struct ieee80211_rx_status *rx_status, 414 struct ieee802_11_elems *elems, 415 bool beacon) 416{ 417 struct ieee80211_local *local = sdata->local; 418 int freq; 419 struct cfg80211_bss *cbss; 420 struct ieee80211_bss *bss; 421 struct sta_info *sta; 422 struct ieee80211_channel *channel; 423 u64 beacon_timestamp, rx_timestamp; 424 u32 supp_rates = 0; 425 enum ieee80211_band band = rx_status->band; 426 struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band]; 427 bool rates_updated = false; 428 429 if (elems->ds_params && elems->ds_params_len == 1) 430 freq = ieee80211_channel_to_frequency(elems->ds_params[0], 431 band); 432 else 433 freq = rx_status->freq; 434 435 channel = ieee80211_get_channel(local->hw.wiphy, freq); 436 437 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 438 return; 439 440 if (sdata->vif.type == NL80211_IFTYPE_ADHOC && 441 ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) { 442 443 rcu_read_lock(); 444 sta = sta_info_get(sdata, mgmt->sa); 445 446 if (elems->supp_rates) { 447 supp_rates = ieee80211_sta_get_rates(local, elems, 448 band, NULL); 449 if (sta) { 450 u32 prev_rates; 451 452 prev_rates = sta->sta.supp_rates[band]; 453 /* make sure mandatory rates are always added */ 454 sta->sta.supp_rates[band] = supp_rates | 455 ieee80211_mandatory_rates(local, band); 456 457 if (sta->sta.supp_rates[band] != prev_rates) { 458 ibss_dbg(sdata, 459 "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n", 460 sta->sta.addr, prev_rates, 461 sta->sta.supp_rates[band]); 462 rates_updated = true; 463 } 464 } else { 465 rcu_read_unlock(); 466 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, 467 mgmt->sa, supp_rates, true); 468 } 469 } 470 471 if (sta && elems->wmm_info) 472 set_sta_flag(sta, WLAN_STA_WME); 473 474 if (sta && elems->ht_operation && elems->ht_cap_elem && 475 sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) { 476 /* we both use HT */ 477 struct ieee80211_sta_ht_cap sta_ht_cap_new; 478 enum nl80211_channel_type channel_type = 479 ieee80211_ht_oper_to_channel_type( 480 elems->ht_operation); 481 482 ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband, 483 elems->ht_cap_elem, 484 &sta_ht_cap_new); 485 486 /* 487 * fall back to HT20 if we don't use or use 488 * the other extension channel 489 */ 490 if (!(channel_type == NL80211_CHAN_HT40MINUS || 491 channel_type == NL80211_CHAN_HT40PLUS) || 492 channel_type != sdata->u.ibss.channel_type) 493 sta_ht_cap_new.cap &= 494 ~IEEE80211_HT_CAP_SUP_WIDTH_20_40; 495 496 if (memcmp(&sta->sta.ht_cap, &sta_ht_cap_new, 497 sizeof(sta_ht_cap_new))) { 498 memcpy(&sta->sta.ht_cap, &sta_ht_cap_new, 499 sizeof(sta_ht_cap_new)); 500 rates_updated = true; 501 } 502 } 503 504 if (sta && rates_updated) { 505 drv_sta_rc_update(local, sdata, &sta->sta, 506 IEEE80211_RC_SUPP_RATES_CHANGED); 507 rate_control_rate_init(sta); 508 } 509 510 rcu_read_unlock(); 511 } 512 513 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems, 514 channel, beacon); 515 if (!bss) 516 return; 517 518 cbss = container_of((void *)bss, struct cfg80211_bss, priv); 519 520 /* was just updated in ieee80211_bss_info_update */ 521 beacon_timestamp = cbss->tsf; 522 523 /* check if we need to merge IBSS */ 524 525 /* we use a fixed BSSID */ 526 if (sdata->u.ibss.fixed_bssid) 527 goto put_bss; 528 529 /* not an IBSS */ 530 if (!(cbss->capability & WLAN_CAPABILITY_IBSS)) 531 goto put_bss; 532 533 /* different channel */ 534 if (sdata->u.ibss.fixed_channel && 535 sdata->u.ibss.channel != cbss->channel) 536 goto put_bss; 537 538 /* different SSID */ 539 if (elems->ssid_len != sdata->u.ibss.ssid_len || 540 memcmp(elems->ssid, sdata->u.ibss.ssid, 541 sdata->u.ibss.ssid_len)) 542 goto put_bss; 543 544 /* same BSSID */ 545 if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid)) 546 goto put_bss; 547 548 if (ieee80211_have_rx_timestamp(rx_status)) { 549 /* time when timestamp field was received */ 550 rx_timestamp = 551 ieee80211_calculate_rx_timestamp(local, rx_status, 552 len + FCS_LEN, 24); 553 } else { 554 /* 555 * second best option: get current TSF 556 * (will return -1 if not supported) 557 */ 558 rx_timestamp = drv_get_tsf(local, sdata); 559 } 560 561 ibss_dbg(sdata, 562 "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n", 563 mgmt->sa, mgmt->bssid, 564 (unsigned long long)rx_timestamp, 565 (unsigned long long)beacon_timestamp, 566 (unsigned long long)(rx_timestamp - beacon_timestamp), 567 jiffies); 568 569 if (beacon_timestamp > rx_timestamp) { 570 ibss_dbg(sdata, 571 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n", 572 mgmt->bssid); 573 ieee80211_sta_join_ibss(sdata, bss); 574 supp_rates = ieee80211_sta_get_rates(local, elems, band, NULL); 575 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 576 supp_rates, true); 577 rcu_read_unlock(); 578 } 579 580 put_bss: 581 ieee80211_rx_bss_put(local, bss); 582} 583 584void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata, 585 const u8 *bssid, const u8 *addr, 586 u32 supp_rates) 587{ 588 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 589 struct ieee80211_local *local = sdata->local; 590 struct sta_info *sta; 591 struct ieee80211_chanctx_conf *chanctx_conf; 592 int band; 593 594 /* 595 * XXX: Consider removing the least recently used entry and 596 * allow new one to be added. 597 */ 598 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 599 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n", 600 sdata->name, addr); 601 return; 602 } 603 604 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) 605 return; 606 607 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) 608 return; 609 610 rcu_read_lock(); 611 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); 612 if (WARN_ON_ONCE(!chanctx_conf)) { 613 rcu_read_unlock(); 614 return; 615 } 616 band = chanctx_conf->channel->band; 617 rcu_read_unlock(); 618 619 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC); 620 if (!sta) 621 return; 622 623 sta->last_rx = jiffies; 624 625 /* make sure mandatory rates are always added */ 626 sta->sta.supp_rates[band] = supp_rates | 627 ieee80211_mandatory_rates(local, band); 628 629 spin_lock(&ifibss->incomplete_lock); 630 list_add(&sta->list, &ifibss->incomplete_stations); 631 spin_unlock(&ifibss->incomplete_lock); 632 ieee80211_queue_work(&local->hw, &sdata->work); 633} 634 635static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata) 636{ 637 struct ieee80211_local *local = sdata->local; 638 int active = 0; 639 struct sta_info *sta; 640 641 lockdep_assert_held(&sdata->u.ibss.mtx); 642 643 rcu_read_lock(); 644 645 list_for_each_entry_rcu(sta, &local->sta_list, list) { 646 if (sta->sdata == sdata && 647 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL, 648 jiffies)) { 649 active++; 650 break; 651 } 652 } 653 654 rcu_read_unlock(); 655 656 return active; 657} 658 659/* 660 * This function is called with state == IEEE80211_IBSS_MLME_JOINED 661 */ 662 663static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata) 664{ 665 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 666 667 lockdep_assert_held(&ifibss->mtx); 668 669 mod_timer(&ifibss->timer, 670 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 671 672 ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT); 673 674 if (time_before(jiffies, ifibss->last_scan_completed + 675 IEEE80211_IBSS_MERGE_INTERVAL)) 676 return; 677 678 if (ieee80211_sta_active_ibss(sdata)) 679 return; 680 681 if (ifibss->fixed_channel) 682 return; 683 684 sdata_info(sdata, 685 "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n"); 686 687 ieee80211_request_internal_scan(sdata, 688 ifibss->ssid, ifibss->ssid_len, NULL); 689} 690 691static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata) 692{ 693 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 694 u8 bssid[ETH_ALEN]; 695 u16 capability; 696 int i; 697 698 lockdep_assert_held(&ifibss->mtx); 699 700 if (ifibss->fixed_bssid) { 701 memcpy(bssid, ifibss->bssid, ETH_ALEN); 702 } else { 703 /* Generate random, not broadcast, locally administered BSSID. Mix in 704 * own MAC address to make sure that devices that do not have proper 705 * random number generator get different BSSID. */ 706 get_random_bytes(bssid, ETH_ALEN); 707 for (i = 0; i < ETH_ALEN; i++) 708 bssid[i] ^= sdata->vif.addr[i]; 709 bssid[0] &= ~0x01; 710 bssid[0] |= 0x02; 711 } 712 713 sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid); 714 715 capability = WLAN_CAPABILITY_IBSS; 716 717 if (ifibss->privacy) 718 capability |= WLAN_CAPABILITY_PRIVACY; 719 else 720 sdata->drop_unencrypted = 0; 721 722 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int, 723 ifibss->channel, ifibss->basic_rates, 724 capability, 0, true); 725} 726 727/* 728 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH 729 */ 730 731static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata) 732{ 733 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 734 struct ieee80211_local *local = sdata->local; 735 struct cfg80211_bss *cbss; 736 struct ieee80211_channel *chan = NULL; 737 const u8 *bssid = NULL; 738 int active_ibss; 739 u16 capability; 740 741 lockdep_assert_held(&ifibss->mtx); 742 743 active_ibss = ieee80211_sta_active_ibss(sdata); 744 ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss); 745 746 if (active_ibss) 747 return; 748 749 capability = WLAN_CAPABILITY_IBSS; 750 if (ifibss->privacy) 751 capability |= WLAN_CAPABILITY_PRIVACY; 752 if (ifibss->fixed_bssid) 753 bssid = ifibss->bssid; 754 if (ifibss->fixed_channel) 755 chan = ifibss->channel; 756 if (!is_zero_ether_addr(ifibss->bssid)) 757 bssid = ifibss->bssid; 758 cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid, 759 ifibss->ssid, ifibss->ssid_len, 760 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY, 761 capability); 762 763 if (cbss) { 764 struct ieee80211_bss *bss; 765 766 bss = (void *)cbss->priv; 767 ibss_dbg(sdata, 768 "sta_find_ibss: selected %pM current %pM\n", 769 cbss->bssid, ifibss->bssid); 770 sdata_info(sdata, 771 "Selected IBSS BSSID %pM based on configured SSID\n", 772 cbss->bssid); 773 774 ieee80211_sta_join_ibss(sdata, bss); 775 ieee80211_rx_bss_put(local, bss); 776 return; 777 } 778 779 ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n"); 780 781 /* Selected IBSS not found in current scan results - try to scan */ 782 if (time_after(jiffies, ifibss->last_scan_completed + 783 IEEE80211_SCAN_INTERVAL)) { 784 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n"); 785 786 ieee80211_request_internal_scan(sdata, 787 ifibss->ssid, ifibss->ssid_len, 788 ifibss->fixed_channel ? ifibss->channel : NULL); 789 } else { 790 int interval = IEEE80211_SCAN_INTERVAL; 791 792 if (time_after(jiffies, ifibss->ibss_join_req + 793 IEEE80211_IBSS_JOIN_TIMEOUT)) 794 ieee80211_sta_create_ibss(sdata); 795 796 mod_timer(&ifibss->timer, 797 round_jiffies(jiffies + interval)); 798 } 799} 800 801static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata, 802 struct sk_buff *req) 803{ 804 struct ieee80211_mgmt *mgmt = (void *)req->data; 805 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 806 struct ieee80211_local *local = sdata->local; 807 int tx_last_beacon, len = req->len; 808 struct sk_buff *skb; 809 struct ieee80211_mgmt *resp; 810 struct sk_buff *presp; 811 u8 *pos, *end; 812 813 lockdep_assert_held(&ifibss->mtx); 814 815 presp = rcu_dereference_protected(ifibss->presp, 816 lockdep_is_held(&ifibss->mtx)); 817 818 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED || 819 len < 24 + 2 || !presp) 820 return; 821 822 tx_last_beacon = drv_tx_last_beacon(local); 823 824 ibss_dbg(sdata, 825 "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n", 826 mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon); 827 828 if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da)) 829 return; 830 831 if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) && 832 !is_broadcast_ether_addr(mgmt->bssid)) 833 return; 834 835 end = ((u8 *) mgmt) + len; 836 pos = mgmt->u.probe_req.variable; 837 if (pos[0] != WLAN_EID_SSID || 838 pos + 2 + pos[1] > end) { 839 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n", 840 mgmt->sa); 841 return; 842 } 843 if (pos[1] != 0 && 844 (pos[1] != ifibss->ssid_len || 845 memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) { 846 /* Ignore ProbeReq for foreign SSID */ 847 return; 848 } 849 850 /* Reply with ProbeResp */ 851 skb = skb_copy(presp, GFP_KERNEL); 852 if (!skb) 853 return; 854 855 resp = (struct ieee80211_mgmt *) skb->data; 856 memcpy(resp->da, mgmt->sa, ETH_ALEN); 857 ibss_dbg(sdata, "Sending ProbeResp to %pM\n", resp->da); 858 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 859 ieee80211_tx_skb(sdata, skb); 860} 861 862static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata, 863 struct ieee80211_mgmt *mgmt, 864 size_t len, 865 struct ieee80211_rx_status *rx_status) 866{ 867 size_t baselen; 868 struct ieee802_11_elems elems; 869 870 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt; 871 if (baselen > len) 872 return; 873 874 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen, 875 &elems); 876 877 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false); 878} 879 880static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 881 struct ieee80211_mgmt *mgmt, 882 size_t len, 883 struct ieee80211_rx_status *rx_status) 884{ 885 size_t baselen; 886 struct ieee802_11_elems elems; 887 888 /* Process beacon from the current BSS */ 889 baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt; 890 if (baselen > len) 891 return; 892 893 ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems); 894 895 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true); 896} 897 898void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata, 899 struct sk_buff *skb) 900{ 901 struct ieee80211_rx_status *rx_status; 902 struct ieee80211_mgmt *mgmt; 903 u16 fc; 904 905 rx_status = IEEE80211_SKB_RXCB(skb); 906 mgmt = (struct ieee80211_mgmt *) skb->data; 907 fc = le16_to_cpu(mgmt->frame_control); 908 909 mutex_lock(&sdata->u.ibss.mtx); 910 911 if (!sdata->u.ibss.ssid_len) 912 goto mgmt_out; /* not ready to merge yet */ 913 914 switch (fc & IEEE80211_FCTL_STYPE) { 915 case IEEE80211_STYPE_PROBE_REQ: 916 ieee80211_rx_mgmt_probe_req(sdata, skb); 917 break; 918 case IEEE80211_STYPE_PROBE_RESP: 919 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len, 920 rx_status); 921 break; 922 case IEEE80211_STYPE_BEACON: 923 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len, 924 rx_status); 925 break; 926 case IEEE80211_STYPE_AUTH: 927 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len); 928 break; 929 case IEEE80211_STYPE_DEAUTH: 930 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len); 931 break; 932 } 933 934 mgmt_out: 935 mutex_unlock(&sdata->u.ibss.mtx); 936} 937 938void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata) 939{ 940 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 941 struct sta_info *sta; 942 943 mutex_lock(&ifibss->mtx); 944 945 /* 946 * Work could be scheduled after scan or similar 947 * when we aren't even joined (or trying) with a 948 * network. 949 */ 950 if (!ifibss->ssid_len) 951 goto out; 952 953 spin_lock_bh(&ifibss->incomplete_lock); 954 while (!list_empty(&ifibss->incomplete_stations)) { 955 sta = list_first_entry(&ifibss->incomplete_stations, 956 struct sta_info, list); 957 list_del(&sta->list); 958 spin_unlock_bh(&ifibss->incomplete_lock); 959 960 ieee80211_ibss_finish_sta(sta, true); 961 rcu_read_unlock(); 962 spin_lock_bh(&ifibss->incomplete_lock); 963 } 964 spin_unlock_bh(&ifibss->incomplete_lock); 965 966 switch (ifibss->state) { 967 case IEEE80211_IBSS_MLME_SEARCH: 968 ieee80211_sta_find_ibss(sdata); 969 break; 970 case IEEE80211_IBSS_MLME_JOINED: 971 ieee80211_sta_merge_ibss(sdata); 972 break; 973 default: 974 WARN_ON(1); 975 break; 976 } 977 978 out: 979 mutex_unlock(&ifibss->mtx); 980} 981 982static void ieee80211_ibss_timer(unsigned long data) 983{ 984 struct ieee80211_sub_if_data *sdata = 985 (struct ieee80211_sub_if_data *) data; 986 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 987 struct ieee80211_local *local = sdata->local; 988 989 if (local->quiescing) { 990 ifibss->timer_running = true; 991 return; 992 } 993 994 ieee80211_queue_work(&local->hw, &sdata->work); 995} 996 997#ifdef CONFIG_PM 998void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata) 999{ 1000 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1001 1002 if (del_timer_sync(&ifibss->timer)) 1003 ifibss->timer_running = true; 1004} 1005 1006void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata) 1007{ 1008 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1009 1010 if (ifibss->timer_running) { 1011 add_timer(&ifibss->timer); 1012 ifibss->timer_running = false; 1013 } 1014} 1015#endif 1016 1017void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata) 1018{ 1019 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1020 1021 setup_timer(&ifibss->timer, ieee80211_ibss_timer, 1022 (unsigned long) sdata); 1023 mutex_init(&ifibss->mtx); 1024 INIT_LIST_HEAD(&ifibss->incomplete_stations); 1025 spin_lock_init(&ifibss->incomplete_lock); 1026} 1027 1028/* scan finished notification */ 1029void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local) 1030{ 1031 struct ieee80211_sub_if_data *sdata; 1032 1033 mutex_lock(&local->iflist_mtx); 1034 list_for_each_entry(sdata, &local->interfaces, list) { 1035 if (!ieee80211_sdata_running(sdata)) 1036 continue; 1037 if (sdata->vif.type != NL80211_IFTYPE_ADHOC) 1038 continue; 1039 sdata->u.ibss.last_scan_completed = jiffies; 1040 ieee80211_queue_work(&local->hw, &sdata->work); 1041 } 1042 mutex_unlock(&local->iflist_mtx); 1043} 1044 1045int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata, 1046 struct cfg80211_ibss_params *params) 1047{ 1048 struct sk_buff *skb; 1049 u32 changed = 0; 1050 1051 skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom + 1052 sizeof(struct ieee80211_hdr_3addr) + 1053 12 /* struct ieee80211_mgmt.u.beacon */ + 1054 2 + IEEE80211_MAX_SSID_LEN /* max SSID */ + 1055 2 + 8 /* max Supported Rates */ + 1056 3 /* max DS params */ + 1057 4 /* IBSS params */ + 1058 2 + (IEEE80211_MAX_SUPP_RATES - 8) + 1059 2 + sizeof(struct ieee80211_ht_cap) + 1060 2 + sizeof(struct ieee80211_ht_operation) + 1061 params->ie_len); 1062 if (!skb) 1063 return -ENOMEM; 1064 1065 mutex_lock(&sdata->u.ibss.mtx); 1066 1067 if (params->bssid) { 1068 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN); 1069 sdata->u.ibss.fixed_bssid = true; 1070 } else 1071 sdata->u.ibss.fixed_bssid = false; 1072 1073 sdata->u.ibss.privacy = params->privacy; 1074 sdata->u.ibss.control_port = params->control_port; 1075 sdata->u.ibss.basic_rates = params->basic_rates; 1076 memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate, 1077 sizeof(params->mcast_rate)); 1078 1079 sdata->vif.bss_conf.beacon_int = params->beacon_interval; 1080 1081 sdata->u.ibss.channel = params->channel; 1082 sdata->u.ibss.channel_type = params->channel_type; 1083 sdata->u.ibss.fixed_channel = params->channel_fixed; 1084 1085 if (params->ie) { 1086 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len, 1087 GFP_KERNEL); 1088 if (sdata->u.ibss.ie) 1089 sdata->u.ibss.ie_len = params->ie_len; 1090 } 1091 1092 sdata->u.ibss.skb = skb; 1093 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; 1094 sdata->u.ibss.ibss_join_req = jiffies; 1095 1096 memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len); 1097 sdata->u.ibss.ssid_len = params->ssid_len; 1098 1099 mutex_unlock(&sdata->u.ibss.mtx); 1100 1101 mutex_lock(&sdata->local->mtx); 1102 ieee80211_recalc_idle(sdata->local); 1103 mutex_unlock(&sdata->local->mtx); 1104 1105 /* 1106 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is 1107 * reserved, but an HT STA shall protect HT transmissions as though 1108 * the HT Protection field were set to non-HT mixed mode. 1109 * 1110 * In an IBSS, the RIFS Mode field of the HT Operation element is 1111 * also reserved, but an HT STA shall operate as though this field 1112 * were set to 1. 1113 */ 1114 1115 sdata->vif.bss_conf.ht_operation_mode |= 1116 IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED 1117 | IEEE80211_HT_PARAM_RIFS_MODE; 1118 1119 changed |= BSS_CHANGED_HT; 1120 ieee80211_bss_info_change_notify(sdata, changed); 1121 1122 sdata->smps_mode = IEEE80211_SMPS_OFF; 1123 sdata->needed_rx_chains = sdata->local->rx_chains; 1124 1125 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 1126 1127 return 0; 1128} 1129 1130int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata) 1131{ 1132 struct sk_buff *skb; 1133 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1134 struct ieee80211_local *local = sdata->local; 1135 struct cfg80211_bss *cbss; 1136 u16 capability; 1137 int active_ibss; 1138 struct sta_info *sta; 1139 1140 mutex_lock(&sdata->u.ibss.mtx); 1141 1142 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; 1143 memset(sdata->u.ibss.bssid, 0, ETH_ALEN); 1144 sdata->u.ibss.ssid_len = 0; 1145 1146 active_ibss = ieee80211_sta_active_ibss(sdata); 1147 1148 if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) { 1149 capability = WLAN_CAPABILITY_IBSS; 1150 1151 if (ifibss->privacy) 1152 capability |= WLAN_CAPABILITY_PRIVACY; 1153 1154 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel, 1155 ifibss->bssid, ifibss->ssid, 1156 ifibss->ssid_len, WLAN_CAPABILITY_IBSS | 1157 WLAN_CAPABILITY_PRIVACY, 1158 capability); 1159 1160 if (cbss) { 1161 cfg80211_unlink_bss(local->hw.wiphy, cbss); 1162 cfg80211_put_bss(cbss); 1163 } 1164 } 1165 1166 sta_info_flush(sdata->local, sdata); 1167 1168 spin_lock_bh(&ifibss->incomplete_lock); 1169 while (!list_empty(&ifibss->incomplete_stations)) { 1170 sta = list_first_entry(&ifibss->incomplete_stations, 1171 struct sta_info, list); 1172 list_del(&sta->list); 1173 spin_unlock_bh(&ifibss->incomplete_lock); 1174 1175 sta_info_free(local, sta); 1176 spin_lock_bh(&ifibss->incomplete_lock); 1177 } 1178 spin_unlock_bh(&ifibss->incomplete_lock); 1179 1180 netif_carrier_off(sdata->dev); 1181 1182 /* remove beacon */ 1183 kfree(sdata->u.ibss.ie); 1184 skb = rcu_dereference_protected(sdata->u.ibss.presp, 1185 lockdep_is_held(&sdata->u.ibss.mtx)); 1186 RCU_INIT_POINTER(sdata->u.ibss.presp, NULL); 1187 sdata->vif.bss_conf.ibss_joined = false; 1188 sdata->vif.bss_conf.ibss_creator = false; 1189 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED | 1190 BSS_CHANGED_IBSS); 1191 synchronize_rcu(); 1192 kfree_skb(skb); 1193 1194 skb_queue_purge(&sdata->skb_queue); 1195 1196 del_timer_sync(&sdata->u.ibss.timer); 1197 1198 mutex_unlock(&sdata->u.ibss.mtx); 1199 1200 mutex_lock(&local->mtx); 1201 ieee80211_recalc_idle(sdata->local); 1202 mutex_unlock(&local->mtx); 1203 1204 return 0; 1205} 1206