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_SCAN_INTERVAL_SLOW (15 * HZ) 30 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ) 31 32 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ) 33 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ) 34 35 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128 36 37 38 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 39 const u8 *bssid, const int beacon_int, 40 struct ieee80211_channel *chan, 41 const u32 basic_rates, 42 const u16 capability, u64 tsf) 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 netif_carrier_off(sdata->dev); 76 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IBSS); 77 } 78 79 memcpy(ifibss->bssid, bssid, ETH_ALEN); 80 81 sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0; 82 83 local->oper_channel = chan; 84 channel_type = ifibss->channel_type; 85 if (channel_type > NL80211_CHAN_HT20 && 86 !cfg80211_can_beacon_sec_chan(local->hw.wiphy, chan, channel_type)) 87 channel_type = NL80211_CHAN_HT20; 88 if (!ieee80211_set_channel_type(local, sdata, channel_type)) { 89 /* can only fail due to HT40+/- mismatch */ 90 channel_type = NL80211_CHAN_HT20; 91 WARN_ON(!ieee80211_set_channel_type(local, sdata, 92 NL80211_CHAN_HT20)); 93 } 94 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); 95 96 sband = local->hw.wiphy->bands[chan->band]; 97 98 /* build supported rates array */ 99 pos = supp_rates; 100 for (i = 0; i < sband->n_bitrates; i++) { 101 int rate = sband->bitrates[i].bitrate; 102 u8 basic = 0; 103 if (basic_rates & BIT(i)) 104 basic = 0x80; 105 *pos++ = basic | (u8) (rate / 5); 106 } 107 108 /* Build IBSS probe response */ 109 mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon)); 110 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon)); 111 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 112 IEEE80211_STYPE_PROBE_RESP); 113 memset(mgmt->da, 0xff, ETH_ALEN); 114 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 115 memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN); 116 mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int); 117 mgmt->u.beacon.timestamp = cpu_to_le64(tsf); 118 mgmt->u.beacon.capab_info = cpu_to_le16(capability); 119 120 pos = skb_put(skb, 2 + ifibss->ssid_len); 121 *pos++ = WLAN_EID_SSID; 122 *pos++ = ifibss->ssid_len; 123 memcpy(pos, ifibss->ssid, ifibss->ssid_len); 124 125 rates = sband->n_bitrates; 126 if (rates > 8) 127 rates = 8; 128 pos = skb_put(skb, 2 + rates); 129 *pos++ = WLAN_EID_SUPP_RATES; 130 *pos++ = rates; 131 memcpy(pos, supp_rates, rates); 132 133 if (sband->band == IEEE80211_BAND_2GHZ) { 134 pos = skb_put(skb, 2 + 1); 135 *pos++ = WLAN_EID_DS_PARAMS; 136 *pos++ = 1; 137 *pos++ = ieee80211_frequency_to_channel(chan->center_freq); 138 } 139 140 pos = skb_put(skb, 2 + 2); 141 *pos++ = WLAN_EID_IBSS_PARAMS; 142 *pos++ = 2; 143 /* FIX: set ATIM window based on scan results */ 144 *pos++ = 0; 145 *pos++ = 0; 146 147 if (sband->n_bitrates > 8) { 148 rates = sband->n_bitrates - 8; 149 pos = skb_put(skb, 2 + rates); 150 *pos++ = WLAN_EID_EXT_SUPP_RATES; 151 *pos++ = rates; 152 memcpy(pos, &supp_rates[8], rates); 153 } 154 155 if (ifibss->ie_len) 156 memcpy(skb_put(skb, ifibss->ie_len), 157 ifibss->ie, ifibss->ie_len); 158 159 /* add HT capability and information IEs */ 160 if (channel_type && sband->ht_cap.ht_supported) { 161 pos = skb_put(skb, 4 + 162 sizeof(struct ieee80211_ht_cap) + 163 sizeof(struct ieee80211_ht_operation)); 164 pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap, 165 sband->ht_cap.cap); 166 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap, 167 chan, channel_type, 0); 168 } 169 170 if (local->hw.queues >= IEEE80211_NUM_ACS) { 171 pos = skb_put(skb, 9); 172 *pos++ = WLAN_EID_VENDOR_SPECIFIC; 173 *pos++ = 7; /* len */ 174 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */ 175 *pos++ = 0x50; 176 *pos++ = 0xf2; 177 *pos++ = 2; /* WME */ 178 *pos++ = 0; /* WME info */ 179 *pos++ = 1; /* WME ver */ 180 *pos++ = 0; /* U-APSD no in use */ 181 } 182 183 rcu_assign_pointer(ifibss->presp, skb); 184 185 sdata->vif.bss_conf.beacon_int = beacon_int; 186 sdata->vif.bss_conf.basic_rates = basic_rates; 187 bss_change = BSS_CHANGED_BEACON_INT; 188 bss_change |= ieee80211_reset_erp_info(sdata); 189 bss_change |= BSS_CHANGED_BSSID; 190 bss_change |= BSS_CHANGED_BEACON; 191 bss_change |= BSS_CHANGED_BEACON_ENABLED; 192 bss_change |= BSS_CHANGED_BASIC_RATES; 193 bss_change |= BSS_CHANGED_HT; 194 bss_change |= BSS_CHANGED_IBSS; 195 sdata->vif.bss_conf.ibss_joined = true; 196 ieee80211_bss_info_change_notify(sdata, bss_change); 197 198 ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates); 199 200 ifibss->state = IEEE80211_IBSS_MLME_JOINED; 201 mod_timer(&ifibss->timer, 202 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 203 204 bss = cfg80211_inform_bss_frame(local->hw.wiphy, local->hw.conf.channel, 205 mgmt, skb->len, 0, GFP_KERNEL); 206 cfg80211_put_bss(bss); 207 netif_carrier_on(sdata->dev); 208 cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL); 209 } 210 211 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 212 struct ieee80211_bss *bss) 213 { 214 struct cfg80211_bss *cbss = 215 container_of((void *)bss, struct cfg80211_bss, priv); 216 struct ieee80211_supported_band *sband; 217 u32 basic_rates; 218 int i, j; 219 u16 beacon_int = cbss->beacon_interval; 220 221 lockdep_assert_held(&sdata->u.ibss.mtx); 222 223 if (beacon_int < 10) 224 beacon_int = 10; 225 226 sband = sdata->local->hw.wiphy->bands[cbss->channel->band]; 227 228 basic_rates = 0; 229 230 for (i = 0; i < bss->supp_rates_len; i++) { 231 int rate = (bss->supp_rates[i] & 0x7f) * 5; 232 bool is_basic = !!(bss->supp_rates[i] & 0x80); 233 234 for (j = 0; j < sband->n_bitrates; j++) { 235 if (sband->bitrates[j].bitrate == rate) { 236 if (is_basic) 237 basic_rates |= BIT(j); 238 break; 239 } 240 } 241 } 242 243 __ieee80211_sta_join_ibss(sdata, cbss->bssid, 244 beacon_int, 245 cbss->channel, 246 basic_rates, 247 cbss->capability, 248 cbss->tsf); 249 } 250 251 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta, 252 bool auth) 253 __acquires(RCU) 254 { 255 struct ieee80211_sub_if_data *sdata = sta->sdata; 256 u8 addr[ETH_ALEN]; 257 258 memcpy(addr, sta->sta.addr, ETH_ALEN); 259 260 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 261 wiphy_debug(sdata->local->hw.wiphy, 262 "Adding new IBSS station %pM (dev=%s)\n", 263 addr, sdata->name); 264 #endif 265 266 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH); 267 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC); 268 /* authorize the station only if the network is not RSN protected. If 269 * not wait for the userspace to authorize it */ 270 if (!sta->sdata->u.ibss.control_port) 271 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED); 272 273 rate_control_rate_init(sta); 274 275 /* If it fails, maybe we raced another insertion? */ 276 if (sta_info_insert_rcu(sta)) 277 return sta_info_get(sdata, addr); 278 if (auth) { 279 #ifdef CONFIG_MAC80211_IBSS_DEBUG 280 printk(KERN_DEBUG "TX Auth SA=%pM DA=%pM BSSID=%pM" 281 "(auth_transaction=1)\n", sdata->vif.addr, 282 sdata->u.ibss.bssid, addr); 283 #endif 284 ieee80211_send_auth(sdata, 1, WLAN_AUTH_OPEN, NULL, 0, 285 addr, sdata->u.ibss.bssid, NULL, 0, 0); 286 } 287 return sta; 288 } 289 290 static struct sta_info * 291 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, 292 const u8 *bssid, const u8 *addr, 293 u32 supp_rates, bool auth) 294 __acquires(RCU) 295 { 296 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 297 struct ieee80211_local *local = sdata->local; 298 struct sta_info *sta; 299 int band = local->hw.conf.channel->band; 300 301 /* 302 * XXX: Consider removing the least recently used entry and 303 * allow new one to be added. 304 */ 305 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 306 net_dbg_ratelimited("%s: No room for a new IBSS STA entry %pM\n", 307 sdata->name, addr); 308 rcu_read_lock(); 309 return NULL; 310 } 311 312 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) { 313 rcu_read_lock(); 314 return NULL; 315 } 316 317 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) { 318 rcu_read_lock(); 319 return NULL; 320 } 321 322 sta = sta_info_alloc(sdata, addr, GFP_KERNEL); 323 if (!sta) { 324 rcu_read_lock(); 325 return NULL; 326 } 327 328 sta->last_rx = jiffies; 329 330 /* make sure mandatory rates are always added */ 331 sta->sta.supp_rates[band] = supp_rates | 332 ieee80211_mandatory_rates(local, band); 333 334 return ieee80211_ibss_finish_sta(sta, auth); 335 } 336 337 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata, 338 struct ieee80211_mgmt *mgmt, 339 size_t len) 340 { 341 u16 auth_alg, auth_transaction; 342 343 lockdep_assert_held(&sdata->u.ibss.mtx); 344 345 if (len < 24 + 6) 346 return; 347 348 auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg); 349 auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction); 350 351 if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1) 352 return; 353 #ifdef CONFIG_MAC80211_IBSS_DEBUG 354 printk(KERN_DEBUG "%s: RX Auth SA=%pM DA=%pM BSSID=%pM." 355 "(auth_transaction=%d)\n", 356 sdata->name, mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction); 357 #endif 358 sta_info_destroy_addr(sdata, mgmt->sa); 359 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 0, false); 360 rcu_read_unlock(); 361 362 /* 363 * IEEE 802.11 standard does not require authentication in IBSS 364 * networks and most implementations do not seem to use it. 365 * However, try to reply to authentication attempts if someone 366 * has actually implemented this. 367 */ 368 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, NULL, 0, 369 mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0); 370 } 371 372 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, 373 struct ieee80211_mgmt *mgmt, 374 size_t len, 375 struct ieee80211_rx_status *rx_status, 376 struct ieee802_11_elems *elems, 377 bool beacon) 378 { 379 struct ieee80211_local *local = sdata->local; 380 int freq; 381 struct cfg80211_bss *cbss; 382 struct ieee80211_bss *bss; 383 struct sta_info *sta; 384 struct ieee80211_channel *channel; 385 u64 beacon_timestamp, rx_timestamp; 386 u32 supp_rates = 0; 387 enum ieee80211_band band = rx_status->band; 388 struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band]; 389 bool rates_updated = false; 390 391 if (elems->ds_params && elems->ds_params_len == 1) 392 freq = ieee80211_channel_to_frequency(elems->ds_params[0], 393 band); 394 else 395 freq = rx_status->freq; 396 397 channel = ieee80211_get_channel(local->hw.wiphy, freq); 398 399 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 400 return; 401 402 if (sdata->vif.type == NL80211_IFTYPE_ADHOC && 403 ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) { 404 405 rcu_read_lock(); 406 sta = sta_info_get(sdata, mgmt->sa); 407 408 if (elems->supp_rates) { 409 supp_rates = ieee80211_sta_get_rates(local, elems, 410 band, NULL); 411 if (sta) { 412 u32 prev_rates; 413 414 prev_rates = sta->sta.supp_rates[band]; 415 /* make sure mandatory rates are always added */ 416 sta->sta.supp_rates[band] = supp_rates | 417 ieee80211_mandatory_rates(local, band); 418 419 if (sta->sta.supp_rates[band] != prev_rates) { 420 #ifdef CONFIG_MAC80211_IBSS_DEBUG 421 printk(KERN_DEBUG 422 "%s: updated supp_rates set " 423 "for %pM based on beacon" 424 "/probe_resp (0x%x -> 0x%x)\n", 425 sdata->name, sta->sta.addr, 426 prev_rates, 427 sta->sta.supp_rates[band]); 428 #endif 429 rates_updated = true; 430 } 431 } else { 432 rcu_read_unlock(); 433 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, 434 mgmt->sa, supp_rates, true); 435 } 436 } 437 438 if (sta && elems->wmm_info) 439 set_sta_flag(sta, WLAN_STA_WME); 440 441 if (sta && elems->ht_operation && elems->ht_cap_elem && 442 sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) { 443 /* we both use HT */ 444 struct ieee80211_sta_ht_cap sta_ht_cap_new; 445 enum nl80211_channel_type channel_type = 446 ieee80211_ht_oper_to_channel_type( 447 elems->ht_operation); 448 449 ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband, 450 elems->ht_cap_elem, 451 &sta_ht_cap_new); 452 453 /* 454 * fall back to HT20 if we don't use or use 455 * the other extension channel 456 */ 457 if (!(channel_type == NL80211_CHAN_HT40MINUS || 458 channel_type == NL80211_CHAN_HT40PLUS) || 459 channel_type != sdata->u.ibss.channel_type) 460 sta_ht_cap_new.cap &= 461 ~IEEE80211_HT_CAP_SUP_WIDTH_20_40; 462 463 if (memcmp(&sta->sta.ht_cap, &sta_ht_cap_new, 464 sizeof(sta_ht_cap_new))) { 465 memcpy(&sta->sta.ht_cap, &sta_ht_cap_new, 466 sizeof(sta_ht_cap_new)); 467 rates_updated = true; 468 } 469 } 470 471 if (sta && rates_updated) 472 rate_control_rate_init(sta); 473 474 rcu_read_unlock(); 475 } 476 477 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems, 478 channel, beacon); 479 if (!bss) 480 return; 481 482 cbss = container_of((void *)bss, struct cfg80211_bss, priv); 483 484 /* was just updated in ieee80211_bss_info_update */ 485 beacon_timestamp = cbss->tsf; 486 487 /* check if we need to merge IBSS */ 488 489 /* we use a fixed BSSID */ 490 if (sdata->u.ibss.fixed_bssid) 491 goto put_bss; 492 493 /* not an IBSS */ 494 if (!(cbss->capability & WLAN_CAPABILITY_IBSS)) 495 goto put_bss; 496 497 /* different channel */ 498 if (cbss->channel != local->oper_channel) 499 goto put_bss; 500 501 /* different SSID */ 502 if (elems->ssid_len != sdata->u.ibss.ssid_len || 503 memcmp(elems->ssid, sdata->u.ibss.ssid, 504 sdata->u.ibss.ssid_len)) 505 goto put_bss; 506 507 /* same BSSID */ 508 if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid)) 509 goto put_bss; 510 511 if (rx_status->flag & RX_FLAG_MACTIME_MPDU) { 512 /* 513 * For correct IBSS merging we need mactime; since mactime is 514 * defined as the time the first data symbol of the frame hits 515 * the PHY, and the timestamp of the beacon is defined as "the 516 * time that the data symbol containing the first bit of the 517 * timestamp is transmitted to the PHY plus the transmitting 518 * STA's delays through its local PHY from the MAC-PHY 519 * interface to its interface with the WM" (802.11 11.1.2) 520 * - equals the time this bit arrives at the receiver - we have 521 * to take into account the offset between the two. 522 * 523 * E.g. at 1 MBit that means mactime is 192 usec earlier 524 * (=24 bytes * 8 usecs/byte) than the beacon timestamp. 525 */ 526 int rate; 527 528 if (rx_status->flag & RX_FLAG_HT) 529 rate = 65; /* TODO: HT rates */ 530 else 531 rate = local->hw.wiphy->bands[band]-> 532 bitrates[rx_status->rate_idx].bitrate; 533 534 rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate); 535 } else { 536 /* 537 * second best option: get current TSF 538 * (will return -1 if not supported) 539 */ 540 rx_timestamp = drv_get_tsf(local, sdata); 541 } 542 543 #ifdef CONFIG_MAC80211_IBSS_DEBUG 544 printk(KERN_DEBUG "RX beacon SA=%pM BSSID=" 545 "%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n", 546 mgmt->sa, mgmt->bssid, 547 (unsigned long long)rx_timestamp, 548 (unsigned long long)beacon_timestamp, 549 (unsigned long long)(rx_timestamp - beacon_timestamp), 550 jiffies); 551 #endif 552 553 if (beacon_timestamp > rx_timestamp) { 554 #ifdef CONFIG_MAC80211_IBSS_DEBUG 555 printk(KERN_DEBUG "%s: beacon TSF higher than " 556 "local TSF - IBSS merge with BSSID %pM\n", 557 sdata->name, mgmt->bssid); 558 #endif 559 ieee80211_sta_join_ibss(sdata, bss); 560 supp_rates = ieee80211_sta_get_rates(local, elems, band, NULL); 561 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 562 supp_rates, true); 563 rcu_read_unlock(); 564 } 565 566 put_bss: 567 ieee80211_rx_bss_put(local, bss); 568 } 569 570 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata, 571 const u8 *bssid, const u8 *addr, 572 u32 supp_rates) 573 { 574 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 575 struct ieee80211_local *local = sdata->local; 576 struct sta_info *sta; 577 int band = local->hw.conf.channel->band; 578 579 /* 580 * XXX: Consider removing the least recently used entry and 581 * allow new one to be added. 582 */ 583 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 584 net_dbg_ratelimited("%s: No room for a new IBSS STA entry %pM\n", 585 sdata->name, addr); 586 return; 587 } 588 589 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) 590 return; 591 592 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) 593 return; 594 595 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC); 596 if (!sta) 597 return; 598 599 sta->last_rx = jiffies; 600 601 /* make sure mandatory rates are always added */ 602 sta->sta.supp_rates[band] = supp_rates | 603 ieee80211_mandatory_rates(local, band); 604 605 spin_lock(&ifibss->incomplete_lock); 606 list_add(&sta->list, &ifibss->incomplete_stations); 607 spin_unlock(&ifibss->incomplete_lock); 608 ieee80211_queue_work(&local->hw, &sdata->work); 609 } 610 611 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata) 612 { 613 struct ieee80211_local *local = sdata->local; 614 int active = 0; 615 struct sta_info *sta; 616 617 lockdep_assert_held(&sdata->u.ibss.mtx); 618 619 rcu_read_lock(); 620 621 list_for_each_entry_rcu(sta, &local->sta_list, list) { 622 if (sta->sdata == sdata && 623 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL, 624 jiffies)) { 625 active++; 626 break; 627 } 628 } 629 630 rcu_read_unlock(); 631 632 return active; 633 } 634 635 /* 636 * This function is called with state == IEEE80211_IBSS_MLME_JOINED 637 */ 638 639 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata) 640 { 641 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 642 643 lockdep_assert_held(&ifibss->mtx); 644 645 mod_timer(&ifibss->timer, 646 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 647 648 ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT); 649 650 if (time_before(jiffies, ifibss->last_scan_completed + 651 IEEE80211_IBSS_MERGE_INTERVAL)) 652 return; 653 654 if (ieee80211_sta_active_ibss(sdata)) 655 return; 656 657 if (ifibss->fixed_channel) 658 return; 659 660 printk(KERN_DEBUG "%s: No active IBSS STAs - trying to scan for other " 661 "IBSS networks with same SSID (merge)\n", sdata->name); 662 663 ieee80211_request_internal_scan(sdata, 664 ifibss->ssid, ifibss->ssid_len, NULL); 665 } 666 667 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata) 668 { 669 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 670 u8 bssid[ETH_ALEN]; 671 u16 capability; 672 int i; 673 674 lockdep_assert_held(&ifibss->mtx); 675 676 if (ifibss->fixed_bssid) { 677 memcpy(bssid, ifibss->bssid, ETH_ALEN); 678 } else { 679 /* Generate random, not broadcast, locally administered BSSID. Mix in 680 * own MAC address to make sure that devices that do not have proper 681 * random number generator get different BSSID. */ 682 get_random_bytes(bssid, ETH_ALEN); 683 for (i = 0; i < ETH_ALEN; i++) 684 bssid[i] ^= sdata->vif.addr[i]; 685 bssid[0] &= ~0x01; 686 bssid[0] |= 0x02; 687 } 688 689 printk(KERN_DEBUG "%s: Creating new IBSS network, BSSID %pM\n", 690 sdata->name, bssid); 691 692 capability = WLAN_CAPABILITY_IBSS; 693 694 if (ifibss->privacy) 695 capability |= WLAN_CAPABILITY_PRIVACY; 696 else 697 sdata->drop_unencrypted = 0; 698 699 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int, 700 ifibss->channel, ifibss->basic_rates, 701 capability, 0); 702 } 703 704 /* 705 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH 706 */ 707 708 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata) 709 { 710 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 711 struct ieee80211_local *local = sdata->local; 712 struct cfg80211_bss *cbss; 713 struct ieee80211_channel *chan = NULL; 714 const u8 *bssid = NULL; 715 int active_ibss; 716 u16 capability; 717 718 lockdep_assert_held(&ifibss->mtx); 719 720 active_ibss = ieee80211_sta_active_ibss(sdata); 721 #ifdef CONFIG_MAC80211_IBSS_DEBUG 722 printk(KERN_DEBUG "%s: sta_find_ibss (active_ibss=%d)\n", 723 sdata->name, active_ibss); 724 #endif /* CONFIG_MAC80211_IBSS_DEBUG */ 725 726 if (active_ibss) 727 return; 728 729 capability = WLAN_CAPABILITY_IBSS; 730 if (ifibss->privacy) 731 capability |= WLAN_CAPABILITY_PRIVACY; 732 if (ifibss->fixed_bssid) 733 bssid = ifibss->bssid; 734 if (ifibss->fixed_channel) 735 chan = ifibss->channel; 736 if (!is_zero_ether_addr(ifibss->bssid)) 737 bssid = ifibss->bssid; 738 cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid, 739 ifibss->ssid, ifibss->ssid_len, 740 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY, 741 capability); 742 743 if (cbss) { 744 struct ieee80211_bss *bss; 745 746 bss = (void *)cbss->priv; 747 #ifdef CONFIG_MAC80211_IBSS_DEBUG 748 printk(KERN_DEBUG " sta_find_ibss: selected %pM current " 749 "%pM\n", cbss->bssid, ifibss->bssid); 750 #endif /* CONFIG_MAC80211_IBSS_DEBUG */ 751 752 printk(KERN_DEBUG "%s: Selected IBSS BSSID %pM" 753 " based on configured SSID\n", 754 sdata->name, cbss->bssid); 755 756 ieee80211_sta_join_ibss(sdata, bss); 757 ieee80211_rx_bss_put(local, bss); 758 return; 759 } 760 761 #ifdef CONFIG_MAC80211_IBSS_DEBUG 762 printk(KERN_DEBUG " did not try to join ibss\n"); 763 #endif /* CONFIG_MAC80211_IBSS_DEBUG */ 764 765 /* Selected IBSS not found in current scan results - try to scan */ 766 if (time_after(jiffies, ifibss->last_scan_completed + 767 IEEE80211_SCAN_INTERVAL)) { 768 printk(KERN_DEBUG "%s: Trigger new scan to find an IBSS to " 769 "join\n", sdata->name); 770 771 ieee80211_request_internal_scan(sdata, 772 ifibss->ssid, ifibss->ssid_len, 773 ifibss->fixed_channel ? ifibss->channel : NULL); 774 } else { 775 int interval = IEEE80211_SCAN_INTERVAL; 776 777 if (time_after(jiffies, ifibss->ibss_join_req + 778 IEEE80211_IBSS_JOIN_TIMEOUT)) { 779 if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) { 780 ieee80211_sta_create_ibss(sdata); 781 return; 782 } 783 printk(KERN_DEBUG "%s: IBSS not allowed on" 784 " %d MHz\n", sdata->name, 785 local->hw.conf.channel->center_freq); 786 787 /* No IBSS found - decrease scan interval and continue 788 * scanning. */ 789 interval = IEEE80211_SCAN_INTERVAL_SLOW; 790 } 791 792 mod_timer(&ifibss->timer, 793 round_jiffies(jiffies + interval)); 794 } 795 } 796 797 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata, 798 struct sk_buff *req) 799 { 800 struct ieee80211_mgmt *mgmt = (void *)req->data; 801 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 802 struct ieee80211_local *local = sdata->local; 803 int tx_last_beacon, len = req->len; 804 struct sk_buff *skb; 805 struct ieee80211_mgmt *resp; 806 struct sk_buff *presp; 807 u8 *pos, *end; 808 809 lockdep_assert_held(&ifibss->mtx); 810 811 presp = rcu_dereference_protected(ifibss->presp, 812 lockdep_is_held(&ifibss->mtx)); 813 814 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED || 815 len < 24 + 2 || !presp) 816 return; 817 818 tx_last_beacon = drv_tx_last_beacon(local); 819 820 #ifdef CONFIG_MAC80211_IBSS_DEBUG 821 printk(KERN_DEBUG "%s: RX ProbeReq SA=%pM DA=%pM BSSID=%pM" 822 " (tx_last_beacon=%d)\n", 823 sdata->name, mgmt->sa, mgmt->da, 824 mgmt->bssid, tx_last_beacon); 825 #endif /* CONFIG_MAC80211_IBSS_DEBUG */ 826 827 if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da)) 828 return; 829 830 if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) && 831 !is_broadcast_ether_addr(mgmt->bssid)) 832 return; 833 834 end = ((u8 *) mgmt) + len; 835 pos = mgmt->u.probe_req.variable; 836 if (pos[0] != WLAN_EID_SSID || 837 pos + 2 + pos[1] > end) { 838 #ifdef CONFIG_MAC80211_IBSS_DEBUG 839 printk(KERN_DEBUG "%s: Invalid SSID IE in ProbeReq " 840 "from %pM\n", 841 sdata->name, mgmt->sa); 842 #endif 843 return; 844 } 845 if (pos[1] != 0 && 846 (pos[1] != ifibss->ssid_len || 847 memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) { 848 /* Ignore ProbeReq for foreign SSID */ 849 return; 850 } 851 852 /* Reply with ProbeResp */ 853 skb = skb_copy(presp, GFP_KERNEL); 854 if (!skb) 855 return; 856 857 resp = (struct ieee80211_mgmt *) skb->data; 858 memcpy(resp->da, mgmt->sa, ETH_ALEN); 859 #ifdef CONFIG_MAC80211_IBSS_DEBUG 860 printk(KERN_DEBUG "%s: Sending ProbeResp to %pM\n", 861 sdata->name, resp->da); 862 #endif /* CONFIG_MAC80211_IBSS_DEBUG */ 863 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 864 ieee80211_tx_skb(sdata, skb); 865 } 866 867 static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata, 868 struct ieee80211_mgmt *mgmt, 869 size_t len, 870 struct ieee80211_rx_status *rx_status) 871 { 872 size_t baselen; 873 struct ieee802_11_elems elems; 874 875 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt; 876 if (baselen > len) 877 return; 878 879 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen, 880 &elems); 881 882 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false); 883 } 884 885 static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 886 struct ieee80211_mgmt *mgmt, 887 size_t len, 888 struct ieee80211_rx_status *rx_status) 889 { 890 size_t baselen; 891 struct ieee802_11_elems elems; 892 893 /* Process beacon from the current BSS */ 894 baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt; 895 if (baselen > len) 896 return; 897 898 ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems); 899 900 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true); 901 } 902 903 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata, 904 struct sk_buff *skb) 905 { 906 struct ieee80211_rx_status *rx_status; 907 struct ieee80211_mgmt *mgmt; 908 u16 fc; 909 910 rx_status = IEEE80211_SKB_RXCB(skb); 911 mgmt = (struct ieee80211_mgmt *) skb->data; 912 fc = le16_to_cpu(mgmt->frame_control); 913 914 mutex_lock(&sdata->u.ibss.mtx); 915 916 if (!sdata->u.ibss.ssid_len) 917 goto mgmt_out; /* not ready to merge yet */ 918 919 switch (fc & IEEE80211_FCTL_STYPE) { 920 case IEEE80211_STYPE_PROBE_REQ: 921 ieee80211_rx_mgmt_probe_req(sdata, skb); 922 break; 923 case IEEE80211_STYPE_PROBE_RESP: 924 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len, 925 rx_status); 926 break; 927 case IEEE80211_STYPE_BEACON: 928 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len, 929 rx_status); 930 break; 931 case IEEE80211_STYPE_AUTH: 932 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len); 933 break; 934 } 935 936 mgmt_out: 937 mutex_unlock(&sdata->u.ibss.mtx); 938 } 939 940 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata) 941 { 942 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 943 struct sta_info *sta; 944 945 mutex_lock(&ifibss->mtx); 946 947 /* 948 * Work could be scheduled after scan or similar 949 * when we aren't even joined (or trying) with a 950 * network. 951 */ 952 if (!ifibss->ssid_len) 953 goto out; 954 955 spin_lock_bh(&ifibss->incomplete_lock); 956 while (!list_empty(&ifibss->incomplete_stations)) { 957 sta = list_first_entry(&ifibss->incomplete_stations, 958 struct sta_info, list); 959 list_del(&sta->list); 960 spin_unlock_bh(&ifibss->incomplete_lock); 961 962 ieee80211_ibss_finish_sta(sta, true); 963 rcu_read_unlock(); 964 spin_lock_bh(&ifibss->incomplete_lock); 965 } 966 spin_unlock_bh(&ifibss->incomplete_lock); 967 968 switch (ifibss->state) { 969 case IEEE80211_IBSS_MLME_SEARCH: 970 ieee80211_sta_find_ibss(sdata); 971 break; 972 case IEEE80211_IBSS_MLME_JOINED: 973 ieee80211_sta_merge_ibss(sdata); 974 break; 975 default: 976 WARN_ON(1); 977 break; 978 } 979 980 out: 981 mutex_unlock(&ifibss->mtx); 982 } 983 984 static void ieee80211_ibss_timer(unsigned long data) 985 { 986 struct ieee80211_sub_if_data *sdata = 987 (struct ieee80211_sub_if_data *) data; 988 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 989 struct ieee80211_local *local = sdata->local; 990 991 if (local->quiescing) { 992 ifibss->timer_running = true; 993 return; 994 } 995 996 ieee80211_queue_work(&local->hw, &sdata->work); 997 } 998 999 #ifdef CONFIG_PM 1000 void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata) 1001 { 1002 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1003 1004 if (del_timer_sync(&ifibss->timer)) 1005 ifibss->timer_running = true; 1006 } 1007 1008 void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata) 1009 { 1010 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1011 1012 if (ifibss->timer_running) { 1013 add_timer(&ifibss->timer); 1014 ifibss->timer_running = false; 1015 } 1016 } 1017 #endif 1018 1019 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata) 1020 { 1021 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1022 1023 setup_timer(&ifibss->timer, ieee80211_ibss_timer, 1024 (unsigned long) sdata); 1025 mutex_init(&ifibss->mtx); 1026 INIT_LIST_HEAD(&ifibss->incomplete_stations); 1027 spin_lock_init(&ifibss->incomplete_lock); 1028 } 1029 1030 /* scan finished notification */ 1031 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local) 1032 { 1033 struct ieee80211_sub_if_data *sdata; 1034 1035 mutex_lock(&local->iflist_mtx); 1036 list_for_each_entry(sdata, &local->interfaces, list) { 1037 if (!ieee80211_sdata_running(sdata)) 1038 continue; 1039 if (sdata->vif.type != NL80211_IFTYPE_ADHOC) 1040 continue; 1041 sdata->u.ibss.last_scan_completed = jiffies; 1042 ieee80211_queue_work(&local->hw, &sdata->work); 1043 } 1044 mutex_unlock(&local->iflist_mtx); 1045 } 1046 1047 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata, 1048 struct cfg80211_ibss_params *params) 1049 { 1050 struct sk_buff *skb; 1051 u32 changed = 0; 1052 1053 skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom + 1054 sizeof(struct ieee80211_hdr_3addr) + 1055 12 /* struct ieee80211_mgmt.u.beacon */ + 1056 2 + IEEE80211_MAX_SSID_LEN /* max SSID */ + 1057 2 + 8 /* max Supported Rates */ + 1058 3 /* max DS params */ + 1059 4 /* IBSS params */ + 1060 2 + (IEEE80211_MAX_SUPP_RATES - 8) + 1061 2 + sizeof(struct ieee80211_ht_cap) + 1062 2 + sizeof(struct ieee80211_ht_operation) + 1063 params->ie_len); 1064 if (!skb) 1065 return -ENOMEM; 1066 1067 mutex_lock(&sdata->u.ibss.mtx); 1068 1069 if (params->bssid) { 1070 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN); 1071 sdata->u.ibss.fixed_bssid = true; 1072 } else 1073 sdata->u.ibss.fixed_bssid = false; 1074 1075 sdata->u.ibss.privacy = params->privacy; 1076 sdata->u.ibss.control_port = params->control_port; 1077 sdata->u.ibss.basic_rates = params->basic_rates; 1078 memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate, 1079 sizeof(params->mcast_rate)); 1080 1081 sdata->vif.bss_conf.beacon_int = params->beacon_interval; 1082 1083 sdata->u.ibss.channel = params->channel; 1084 sdata->u.ibss.channel_type = params->channel_type; 1085 sdata->u.ibss.fixed_channel = params->channel_fixed; 1086 1087 /* fix ourselves to that channel now already */ 1088 if (params->channel_fixed) { 1089 sdata->local->oper_channel = params->channel; 1090 if (!ieee80211_set_channel_type(sdata->local, sdata, 1091 params->channel_type)) { 1092 mutex_unlock(&sdata->u.ibss.mtx); 1093 kfree_skb(skb); 1094 return -EINVAL; 1095 } 1096 } 1097 1098 if (params->ie) { 1099 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len, 1100 GFP_KERNEL); 1101 if (sdata->u.ibss.ie) 1102 sdata->u.ibss.ie_len = params->ie_len; 1103 } 1104 1105 sdata->u.ibss.skb = skb; 1106 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; 1107 sdata->u.ibss.ibss_join_req = jiffies; 1108 1109 memcpy(sdata->u.ibss.ssid, params->ssid, IEEE80211_MAX_SSID_LEN); 1110 sdata->u.ibss.ssid_len = params->ssid_len; 1111 1112 mutex_unlock(&sdata->u.ibss.mtx); 1113 1114 mutex_lock(&sdata->local->mtx); 1115 ieee80211_recalc_idle(sdata->local); 1116 mutex_unlock(&sdata->local->mtx); 1117 1118 /* 1119 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is 1120 * reserved, but an HT STA shall protect HT transmissions as though 1121 * the HT Protection field were set to non-HT mixed mode. 1122 * 1123 * In an IBSS, the RIFS Mode field of the HT Operation element is 1124 * also reserved, but an HT STA shall operate as though this field 1125 * were set to 1. 1126 */ 1127 1128 sdata->vif.bss_conf.ht_operation_mode |= 1129 IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED 1130 | IEEE80211_HT_PARAM_RIFS_MODE; 1131 1132 changed |= BSS_CHANGED_HT; 1133 ieee80211_bss_info_change_notify(sdata, changed); 1134 1135 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 1136 1137 return 0; 1138 } 1139 1140 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata) 1141 { 1142 struct sk_buff *skb; 1143 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1144 struct ieee80211_local *local = sdata->local; 1145 struct cfg80211_bss *cbss; 1146 u16 capability; 1147 int active_ibss; 1148 struct sta_info *sta; 1149 1150 mutex_lock(&sdata->u.ibss.mtx); 1151 1152 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; 1153 memset(sdata->u.ibss.bssid, 0, ETH_ALEN); 1154 sdata->u.ibss.ssid_len = 0; 1155 1156 active_ibss = ieee80211_sta_active_ibss(sdata); 1157 1158 if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) { 1159 capability = WLAN_CAPABILITY_IBSS; 1160 1161 if (ifibss->privacy) 1162 capability |= WLAN_CAPABILITY_PRIVACY; 1163 1164 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel, 1165 ifibss->bssid, ifibss->ssid, 1166 ifibss->ssid_len, WLAN_CAPABILITY_IBSS | 1167 WLAN_CAPABILITY_PRIVACY, 1168 capability); 1169 1170 if (cbss) { 1171 cfg80211_unlink_bss(local->hw.wiphy, cbss); 1172 cfg80211_put_bss(cbss); 1173 } 1174 } 1175 1176 sta_info_flush(sdata->local, sdata); 1177 1178 spin_lock_bh(&ifibss->incomplete_lock); 1179 while (!list_empty(&ifibss->incomplete_stations)) { 1180 sta = list_first_entry(&ifibss->incomplete_stations, 1181 struct sta_info, list); 1182 list_del(&sta->list); 1183 spin_unlock_bh(&ifibss->incomplete_lock); 1184 1185 sta_info_free(local, sta); 1186 spin_lock_bh(&ifibss->incomplete_lock); 1187 } 1188 spin_unlock_bh(&ifibss->incomplete_lock); 1189 1190 netif_carrier_off(sdata->dev); 1191 1192 /* remove beacon */ 1193 kfree(sdata->u.ibss.ie); 1194 skb = rcu_dereference_protected(sdata->u.ibss.presp, 1195 lockdep_is_held(&sdata->u.ibss.mtx)); 1196 RCU_INIT_POINTER(sdata->u.ibss.presp, NULL); 1197 sdata->vif.bss_conf.ibss_joined = false; 1198 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED | 1199 BSS_CHANGED_IBSS); 1200 synchronize_rcu(); 1201 kfree_skb(skb); 1202 1203 skb_queue_purge(&sdata->skb_queue); 1204 1205 del_timer_sync(&sdata->u.ibss.timer); 1206 1207 mutex_unlock(&sdata->u.ibss.mtx); 1208 1209 mutex_lock(&local->mtx); 1210 ieee80211_recalc_idle(sdata->local); 1211 mutex_unlock(&local->mtx); 1212 1213 return 0; 1214 } 1215