ibss.c revision 9ebb61a23d90703344fc609fbee8da67b1e7456c
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 38static 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 (compare_ether_addr(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); 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 211static 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 251static 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 290static struct sta_info * 291ieee80211_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 if (net_ratelimit()) 307 printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n", 308 sdata->name, addr); 309 rcu_read_lock(); 310 return NULL; 311 } 312 313 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) { 314 rcu_read_lock(); 315 return NULL; 316 } 317 318 if (compare_ether_addr(bssid, sdata->u.ibss.bssid)) { 319 rcu_read_lock(); 320 return NULL; 321 } 322 323 sta = sta_info_alloc(sdata, addr, GFP_KERNEL); 324 if (!sta) { 325 rcu_read_lock(); 326 return NULL; 327 } 328 329 sta->last_rx = jiffies; 330 331 /* make sure mandatory rates are always added */ 332 sta->sta.supp_rates[band] = supp_rates | 333 ieee80211_mandatory_rates(local, band); 334 335 return ieee80211_ibss_finish_sta(sta, auth); 336} 337 338static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata, 339 struct ieee80211_mgmt *mgmt, 340 size_t len) 341{ 342 u16 auth_alg, auth_transaction; 343 344 lockdep_assert_held(&sdata->u.ibss.mtx); 345 346 if (len < 24 + 6) 347 return; 348 349 auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg); 350 auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction); 351 352 if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1) 353 return; 354#ifdef CONFIG_MAC80211_IBSS_DEBUG 355 printk(KERN_DEBUG "%s: RX Auth SA=%pM DA=%pM BSSID=%pM." 356 "(auth_transaction=%d)\n", 357 sdata->name, mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction); 358#endif 359 sta_info_destroy_addr(sdata, mgmt->sa); 360 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 0, false); 361 rcu_read_unlock(); 362 363 /* 364 * IEEE 802.11 standard does not require authentication in IBSS 365 * networks and most implementations do not seem to use it. 366 * However, try to reply to authentication attempts if someone 367 * has actually implemented this. 368 */ 369 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, NULL, 0, 370 mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0); 371} 372 373static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, 374 struct ieee80211_mgmt *mgmt, 375 size_t len, 376 struct ieee80211_rx_status *rx_status, 377 struct ieee802_11_elems *elems, 378 bool beacon) 379{ 380 struct ieee80211_local *local = sdata->local; 381 int freq; 382 struct cfg80211_bss *cbss; 383 struct ieee80211_bss *bss; 384 struct sta_info *sta; 385 struct ieee80211_channel *channel; 386 u64 beacon_timestamp, rx_timestamp; 387 u32 supp_rates = 0; 388 enum ieee80211_band band = rx_status->band; 389 struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band]; 390 bool rates_updated = false; 391 392 if (elems->ds_params && elems->ds_params_len == 1) 393 freq = ieee80211_channel_to_frequency(elems->ds_params[0], 394 band); 395 else 396 freq = rx_status->freq; 397 398 channel = ieee80211_get_channel(local->hw.wiphy, freq); 399 400 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 401 return; 402 403 if (sdata->vif.type == NL80211_IFTYPE_ADHOC && 404 compare_ether_addr(mgmt->bssid, sdata->u.ibss.bssid) == 0) { 405 406 rcu_read_lock(); 407 sta = sta_info_get(sdata, mgmt->sa); 408 409 if (elems->supp_rates) { 410 supp_rates = ieee80211_sta_get_rates(local, elems, 411 band, NULL); 412 if (sta) { 413 u32 prev_rates; 414 415 prev_rates = sta->sta.supp_rates[band]; 416 /* make sure mandatory rates are always added */ 417 sta->sta.supp_rates[band] = supp_rates | 418 ieee80211_mandatory_rates(local, band); 419 420 if (sta->sta.supp_rates[band] != prev_rates) { 421#ifdef CONFIG_MAC80211_IBSS_DEBUG 422 printk(KERN_DEBUG 423 "%s: updated supp_rates set " 424 "for %pM based on beacon" 425 "/probe_resp (0x%x -> 0x%x)\n", 426 sdata->name, sta->sta.addr, 427 prev_rates, 428 sta->sta.supp_rates[band]); 429#endif 430 rates_updated = true; 431 } 432 } else { 433 rcu_read_unlock(); 434 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, 435 mgmt->sa, supp_rates, true); 436 } 437 } 438 439 if (sta && elems->wmm_info) 440 set_sta_flag(sta, WLAN_STA_WME); 441 442 if (sta && elems->ht_operation && elems->ht_cap_elem && 443 sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) { 444 /* we both use HT */ 445 struct ieee80211_sta_ht_cap sta_ht_cap_new; 446 enum nl80211_channel_type channel_type = 447 ieee80211_ht_oper_to_channel_type( 448 elems->ht_operation); 449 450 ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband, 451 elems->ht_cap_elem, 452 &sta_ht_cap_new); 453 454 /* 455 * fall back to HT20 if we don't use or use 456 * the other extension channel 457 */ 458 if ((channel_type == NL80211_CHAN_HT40MINUS || 459 channel_type == NL80211_CHAN_HT40PLUS) && 460 channel_type != sdata->u.ibss.channel_type) 461 sta_ht_cap_new.cap &= 462 ~IEEE80211_HT_CAP_SUP_WIDTH_20_40; 463 464 if (memcmp(&sta->sta.ht_cap, &sta_ht_cap_new, 465 sizeof(sta_ht_cap_new))) { 466 memcpy(&sta->sta.ht_cap, &sta_ht_cap_new, 467 sizeof(sta_ht_cap_new)); 468 rates_updated = true; 469 } 470 } 471 472 if (sta && rates_updated) 473 rate_control_rate_init(sta); 474 475 rcu_read_unlock(); 476 } 477 478 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems, 479 channel, beacon); 480 if (!bss) 481 return; 482 483 cbss = container_of((void *)bss, struct cfg80211_bss, priv); 484 485 /* was just updated in ieee80211_bss_info_update */ 486 beacon_timestamp = cbss->tsf; 487 488 /* check if we need to merge IBSS */ 489 490 /* we use a fixed BSSID */ 491 if (sdata->u.ibss.fixed_bssid) 492 goto put_bss; 493 494 /* not an IBSS */ 495 if (!(cbss->capability & WLAN_CAPABILITY_IBSS)) 496 goto put_bss; 497 498 /* different channel */ 499 if (cbss->channel != local->oper_channel) 500 goto put_bss; 501 502 /* different SSID */ 503 if (elems->ssid_len != sdata->u.ibss.ssid_len || 504 memcmp(elems->ssid, sdata->u.ibss.ssid, 505 sdata->u.ibss.ssid_len)) 506 goto put_bss; 507 508 /* same BSSID */ 509 if (compare_ether_addr(cbss->bssid, sdata->u.ibss.bssid) == 0) 510 goto put_bss; 511 512 if (rx_status->flag & RX_FLAG_MACTIME_MPDU) { 513 /* 514 * For correct IBSS merging we need mactime; since mactime is 515 * defined as the time the first data symbol of the frame hits 516 * the PHY, and the timestamp of the beacon is defined as "the 517 * time that the data symbol containing the first bit of the 518 * timestamp is transmitted to the PHY plus the transmitting 519 * STA's delays through its local PHY from the MAC-PHY 520 * interface to its interface with the WM" (802.11 11.1.2) 521 * - equals the time this bit arrives at the receiver - we have 522 * to take into account the offset between the two. 523 * 524 * E.g. at 1 MBit that means mactime is 192 usec earlier 525 * (=24 bytes * 8 usecs/byte) than the beacon timestamp. 526 */ 527 int rate; 528 529 if (rx_status->flag & RX_FLAG_HT) 530 rate = 65; /* TODO: HT rates */ 531 else 532 rate = local->hw.wiphy->bands[band]-> 533 bitrates[rx_status->rate_idx].bitrate; 534 535 rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate); 536 } else { 537 /* 538 * second best option: get current TSF 539 * (will return -1 if not supported) 540 */ 541 rx_timestamp = drv_get_tsf(local, sdata); 542 } 543 544#ifdef CONFIG_MAC80211_IBSS_DEBUG 545 printk(KERN_DEBUG "RX beacon SA=%pM BSSID=" 546 "%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n", 547 mgmt->sa, mgmt->bssid, 548 (unsigned long long)rx_timestamp, 549 (unsigned long long)beacon_timestamp, 550 (unsigned long long)(rx_timestamp - beacon_timestamp), 551 jiffies); 552#endif 553 554 if (beacon_timestamp > rx_timestamp) { 555#ifdef CONFIG_MAC80211_IBSS_DEBUG 556 printk(KERN_DEBUG "%s: beacon TSF higher than " 557 "local TSF - IBSS merge with BSSID %pM\n", 558 sdata->name, mgmt->bssid); 559#endif 560 ieee80211_sta_join_ibss(sdata, bss); 561 supp_rates = ieee80211_sta_get_rates(local, elems, band, NULL); 562 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 563 supp_rates, true); 564 rcu_read_unlock(); 565 } 566 567 put_bss: 568 ieee80211_rx_bss_put(local, bss); 569} 570 571void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata, 572 const u8 *bssid, const u8 *addr, 573 u32 supp_rates) 574{ 575 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 576 struct ieee80211_local *local = sdata->local; 577 struct sta_info *sta; 578 int band = local->hw.conf.channel->band; 579 580 /* 581 * XXX: Consider removing the least recently used entry and 582 * allow new one to be added. 583 */ 584 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 585 if (net_ratelimit()) 586 printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n", 587 sdata->name, addr); 588 return; 589 } 590 591 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) 592 return; 593 594 if (compare_ether_addr(bssid, sdata->u.ibss.bssid)) 595 return; 596 597 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC); 598 if (!sta) 599 return; 600 601 sta->last_rx = jiffies; 602 603 /* make sure mandatory rates are always added */ 604 sta->sta.supp_rates[band] = supp_rates | 605 ieee80211_mandatory_rates(local, band); 606 607 spin_lock(&ifibss->incomplete_lock); 608 list_add(&sta->list, &ifibss->incomplete_stations); 609 spin_unlock(&ifibss->incomplete_lock); 610 ieee80211_queue_work(&local->hw, &sdata->work); 611} 612 613static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata) 614{ 615 struct ieee80211_local *local = sdata->local; 616 int active = 0; 617 struct sta_info *sta; 618 619 lockdep_assert_held(&sdata->u.ibss.mtx); 620 621 rcu_read_lock(); 622 623 list_for_each_entry_rcu(sta, &local->sta_list, list) { 624 if (sta->sdata == sdata && 625 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL, 626 jiffies)) { 627 active++; 628 break; 629 } 630 } 631 632 rcu_read_unlock(); 633 634 return active; 635} 636 637/* 638 * This function is called with state == IEEE80211_IBSS_MLME_JOINED 639 */ 640 641static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata) 642{ 643 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 644 645 lockdep_assert_held(&ifibss->mtx); 646 647 mod_timer(&ifibss->timer, 648 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 649 650 ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT); 651 652 if (time_before(jiffies, ifibss->last_scan_completed + 653 IEEE80211_IBSS_MERGE_INTERVAL)) 654 return; 655 656 if (ieee80211_sta_active_ibss(sdata)) 657 return; 658 659 if (ifibss->fixed_channel) 660 return; 661 662 printk(KERN_DEBUG "%s: No active IBSS STAs - trying to scan for other " 663 "IBSS networks with same SSID (merge)\n", sdata->name); 664 665 ieee80211_request_internal_scan(sdata, 666 ifibss->ssid, ifibss->ssid_len, NULL); 667} 668 669static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata) 670{ 671 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 672 u8 bssid[ETH_ALEN]; 673 u16 capability; 674 int i; 675 676 lockdep_assert_held(&ifibss->mtx); 677 678 if (ifibss->fixed_bssid) { 679 memcpy(bssid, ifibss->bssid, ETH_ALEN); 680 } else { 681 /* Generate random, not broadcast, locally administered BSSID. Mix in 682 * own MAC address to make sure that devices that do not have proper 683 * random number generator get different BSSID. */ 684 get_random_bytes(bssid, ETH_ALEN); 685 for (i = 0; i < ETH_ALEN; i++) 686 bssid[i] ^= sdata->vif.addr[i]; 687 bssid[0] &= ~0x01; 688 bssid[0] |= 0x02; 689 } 690 691 printk(KERN_DEBUG "%s: Creating new IBSS network, BSSID %pM\n", 692 sdata->name, bssid); 693 694 capability = WLAN_CAPABILITY_IBSS; 695 696 if (ifibss->privacy) 697 capability |= WLAN_CAPABILITY_PRIVACY; 698 else 699 sdata->drop_unencrypted = 0; 700 701 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int, 702 ifibss->channel, ifibss->basic_rates, 703 capability, 0); 704} 705 706/* 707 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH 708 */ 709 710static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata) 711{ 712 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 713 struct ieee80211_local *local = sdata->local; 714 struct cfg80211_bss *cbss; 715 struct ieee80211_channel *chan = NULL; 716 const u8 *bssid = NULL; 717 int active_ibss; 718 u16 capability; 719 720 lockdep_assert_held(&ifibss->mtx); 721 722 active_ibss = ieee80211_sta_active_ibss(sdata); 723#ifdef CONFIG_MAC80211_IBSS_DEBUG 724 printk(KERN_DEBUG "%s: sta_find_ibss (active_ibss=%d)\n", 725 sdata->name, active_ibss); 726#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 727 728 if (active_ibss) 729 return; 730 731 capability = WLAN_CAPABILITY_IBSS; 732 if (ifibss->privacy) 733 capability |= WLAN_CAPABILITY_PRIVACY; 734 if (ifibss->fixed_bssid) 735 bssid = ifibss->bssid; 736 if (ifibss->fixed_channel) 737 chan = ifibss->channel; 738 if (!is_zero_ether_addr(ifibss->bssid)) 739 bssid = ifibss->bssid; 740 cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid, 741 ifibss->ssid, ifibss->ssid_len, 742 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY, 743 capability); 744 745 if (cbss) { 746 struct ieee80211_bss *bss; 747 748 bss = (void *)cbss->priv; 749#ifdef CONFIG_MAC80211_IBSS_DEBUG 750 printk(KERN_DEBUG " sta_find_ibss: selected %pM current " 751 "%pM\n", cbss->bssid, ifibss->bssid); 752#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 753 754 printk(KERN_DEBUG "%s: Selected IBSS BSSID %pM" 755 " based on configured SSID\n", 756 sdata->name, cbss->bssid); 757 758 ieee80211_sta_join_ibss(sdata, bss); 759 ieee80211_rx_bss_put(local, bss); 760 return; 761 } 762 763#ifdef CONFIG_MAC80211_IBSS_DEBUG 764 printk(KERN_DEBUG " did not try to join ibss\n"); 765#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 766 767 /* Selected IBSS not found in current scan results - try to scan */ 768 if (time_after(jiffies, ifibss->last_scan_completed + 769 IEEE80211_SCAN_INTERVAL)) { 770 printk(KERN_DEBUG "%s: Trigger new scan to find an IBSS to " 771 "join\n", sdata->name); 772 773 ieee80211_request_internal_scan(sdata, 774 ifibss->ssid, ifibss->ssid_len, 775 ifibss->fixed_channel ? ifibss->channel : NULL); 776 } else { 777 int interval = IEEE80211_SCAN_INTERVAL; 778 779 if (time_after(jiffies, ifibss->ibss_join_req + 780 IEEE80211_IBSS_JOIN_TIMEOUT)) { 781 if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) { 782 ieee80211_sta_create_ibss(sdata); 783 return; 784 } 785 printk(KERN_DEBUG "%s: IBSS not allowed on" 786 " %d MHz\n", sdata->name, 787 local->hw.conf.channel->center_freq); 788 789 /* No IBSS found - decrease scan interval and continue 790 * scanning. */ 791 interval = IEEE80211_SCAN_INTERVAL_SLOW; 792 } 793 794 mod_timer(&ifibss->timer, 795 round_jiffies(jiffies + interval)); 796 } 797} 798 799static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata, 800 struct sk_buff *req) 801{ 802 struct ieee80211_mgmt *mgmt = (void *)req->data; 803 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 804 struct ieee80211_local *local = sdata->local; 805 int tx_last_beacon, len = req->len; 806 struct sk_buff *skb; 807 struct ieee80211_mgmt *resp; 808 struct sk_buff *presp; 809 u8 *pos, *end; 810 811 lockdep_assert_held(&ifibss->mtx); 812 813 presp = rcu_dereference_protected(ifibss->presp, 814 lockdep_is_held(&ifibss->mtx)); 815 816 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED || 817 len < 24 + 2 || !presp) 818 return; 819 820 tx_last_beacon = drv_tx_last_beacon(local); 821 822#ifdef CONFIG_MAC80211_IBSS_DEBUG 823 printk(KERN_DEBUG "%s: RX ProbeReq SA=%pM DA=%pM BSSID=%pM" 824 " (tx_last_beacon=%d)\n", 825 sdata->name, mgmt->sa, mgmt->da, 826 mgmt->bssid, tx_last_beacon); 827#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 828 829 if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da)) 830 return; 831 832 if (compare_ether_addr(mgmt->bssid, ifibss->bssid) != 0 && 833 !is_broadcast_ether_addr(mgmt->bssid)) 834 return; 835 836 end = ((u8 *) mgmt) + len; 837 pos = mgmt->u.probe_req.variable; 838 if (pos[0] != WLAN_EID_SSID || 839 pos + 2 + pos[1] > end) { 840#ifdef CONFIG_MAC80211_IBSS_DEBUG 841 printk(KERN_DEBUG "%s: Invalid SSID IE in ProbeReq " 842 "from %pM\n", 843 sdata->name, mgmt->sa); 844#endif 845 return; 846 } 847 if (pos[1] != 0 && 848 (pos[1] != ifibss->ssid_len || 849 memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) { 850 /* Ignore ProbeReq for foreign SSID */ 851 return; 852 } 853 854 /* Reply with ProbeResp */ 855 skb = skb_copy(presp, GFP_KERNEL); 856 if (!skb) 857 return; 858 859 resp = (struct ieee80211_mgmt *) skb->data; 860 memcpy(resp->da, mgmt->sa, ETH_ALEN); 861#ifdef CONFIG_MAC80211_IBSS_DEBUG 862 printk(KERN_DEBUG "%s: Sending ProbeResp to %pM\n", 863 sdata->name, resp->da); 864#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 865 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 866 ieee80211_tx_skb(sdata, skb); 867} 868 869static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata, 870 struct ieee80211_mgmt *mgmt, 871 size_t len, 872 struct ieee80211_rx_status *rx_status) 873{ 874 size_t baselen; 875 struct ieee802_11_elems elems; 876 877 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt; 878 if (baselen > len) 879 return; 880 881 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen, 882 &elems); 883 884 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false); 885} 886 887static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 888 struct ieee80211_mgmt *mgmt, 889 size_t len, 890 struct ieee80211_rx_status *rx_status) 891{ 892 size_t baselen; 893 struct ieee802_11_elems elems; 894 895 /* Process beacon from the current BSS */ 896 baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt; 897 if (baselen > len) 898 return; 899 900 ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems); 901 902 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true); 903} 904 905void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata, 906 struct sk_buff *skb) 907{ 908 struct ieee80211_rx_status *rx_status; 909 struct ieee80211_mgmt *mgmt; 910 u16 fc; 911 912 rx_status = IEEE80211_SKB_RXCB(skb); 913 mgmt = (struct ieee80211_mgmt *) skb->data; 914 fc = le16_to_cpu(mgmt->frame_control); 915 916 mutex_lock(&sdata->u.ibss.mtx); 917 918 if (!sdata->u.ibss.ssid_len) 919 goto mgmt_out; /* not ready to merge yet */ 920 921 switch (fc & IEEE80211_FCTL_STYPE) { 922 case IEEE80211_STYPE_PROBE_REQ: 923 ieee80211_rx_mgmt_probe_req(sdata, skb); 924 break; 925 case IEEE80211_STYPE_PROBE_RESP: 926 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len, 927 rx_status); 928 break; 929 case IEEE80211_STYPE_BEACON: 930 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len, 931 rx_status); 932 break; 933 case IEEE80211_STYPE_AUTH: 934 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len); 935 break; 936 } 937 938 mgmt_out: 939 mutex_unlock(&sdata->u.ibss.mtx); 940} 941 942void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata) 943{ 944 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 945 struct sta_info *sta; 946 947 mutex_lock(&ifibss->mtx); 948 949 /* 950 * Work could be scheduled after scan or similar 951 * when we aren't even joined (or trying) with a 952 * network. 953 */ 954 if (!ifibss->ssid_len) 955 goto out; 956 957 spin_lock_bh(&ifibss->incomplete_lock); 958 while (!list_empty(&ifibss->incomplete_stations)) { 959 sta = list_first_entry(&ifibss->incomplete_stations, 960 struct sta_info, list); 961 list_del(&sta->list); 962 spin_unlock_bh(&ifibss->incomplete_lock); 963 964 ieee80211_ibss_finish_sta(sta, true); 965 rcu_read_unlock(); 966 spin_lock_bh(&ifibss->incomplete_lock); 967 } 968 spin_unlock_bh(&ifibss->incomplete_lock); 969 970 switch (ifibss->state) { 971 case IEEE80211_IBSS_MLME_SEARCH: 972 ieee80211_sta_find_ibss(sdata); 973 break; 974 case IEEE80211_IBSS_MLME_JOINED: 975 ieee80211_sta_merge_ibss(sdata); 976 break; 977 default: 978 WARN_ON(1); 979 break; 980 } 981 982 out: 983 mutex_unlock(&ifibss->mtx); 984} 985 986static void ieee80211_ibss_timer(unsigned long data) 987{ 988 struct ieee80211_sub_if_data *sdata = 989 (struct ieee80211_sub_if_data *) data; 990 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 991 struct ieee80211_local *local = sdata->local; 992 993 if (local->quiescing) { 994 ifibss->timer_running = true; 995 return; 996 } 997 998 ieee80211_queue_work(&local->hw, &sdata->work); 999} 1000 1001#ifdef CONFIG_PM 1002void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata) 1003{ 1004 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1005 1006 if (del_timer_sync(&ifibss->timer)) 1007 ifibss->timer_running = true; 1008} 1009 1010void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata) 1011{ 1012 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1013 1014 if (ifibss->timer_running) { 1015 add_timer(&ifibss->timer); 1016 ifibss->timer_running = false; 1017 } 1018} 1019#endif 1020 1021void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata) 1022{ 1023 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1024 1025 setup_timer(&ifibss->timer, ieee80211_ibss_timer, 1026 (unsigned long) sdata); 1027 mutex_init(&ifibss->mtx); 1028 INIT_LIST_HEAD(&ifibss->incomplete_stations); 1029 spin_lock_init(&ifibss->incomplete_lock); 1030} 1031 1032/* scan finished notification */ 1033void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local) 1034{ 1035 struct ieee80211_sub_if_data *sdata; 1036 1037 mutex_lock(&local->iflist_mtx); 1038 list_for_each_entry(sdata, &local->interfaces, list) { 1039 if (!ieee80211_sdata_running(sdata)) 1040 continue; 1041 if (sdata->vif.type != NL80211_IFTYPE_ADHOC) 1042 continue; 1043 sdata->u.ibss.last_scan_completed = jiffies; 1044 ieee80211_queue_work(&local->hw, &sdata->work); 1045 } 1046 mutex_unlock(&local->iflist_mtx); 1047} 1048 1049int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata, 1050 struct cfg80211_ibss_params *params) 1051{ 1052 struct sk_buff *skb; 1053 u32 changed = 0; 1054 1055 skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom + 1056 sizeof(struct ieee80211_hdr_3addr) + 1057 12 /* struct ieee80211_mgmt.u.beacon */ + 1058 2 + IEEE80211_MAX_SSID_LEN /* max SSID */ + 1059 2 + 8 /* max Supported Rates */ + 1060 3 /* max DS params */ + 1061 4 /* IBSS params */ + 1062 2 + (IEEE80211_MAX_SUPP_RATES - 8) + 1063 2 + sizeof(struct ieee80211_ht_cap) + 1064 2 + sizeof(struct ieee80211_ht_operation) + 1065 params->ie_len); 1066 if (!skb) 1067 return -ENOMEM; 1068 1069 mutex_lock(&sdata->u.ibss.mtx); 1070 1071 if (params->bssid) { 1072 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN); 1073 sdata->u.ibss.fixed_bssid = true; 1074 } else 1075 sdata->u.ibss.fixed_bssid = false; 1076 1077 sdata->u.ibss.privacy = params->privacy; 1078 sdata->u.ibss.control_port = params->control_port; 1079 sdata->u.ibss.basic_rates = params->basic_rates; 1080 memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate, 1081 sizeof(params->mcast_rate)); 1082 1083 sdata->vif.bss_conf.beacon_int = params->beacon_interval; 1084 1085 sdata->u.ibss.channel = params->channel; 1086 sdata->u.ibss.channel_type = params->channel_type; 1087 sdata->u.ibss.fixed_channel = params->channel_fixed; 1088 1089 /* fix ourselves to that channel now already */ 1090 if (params->channel_fixed) { 1091 sdata->local->oper_channel = params->channel; 1092 if (!ieee80211_set_channel_type(sdata->local, sdata, 1093 params->channel_type)) { 1094 mutex_unlock(&sdata->u.ibss.mtx); 1095 kfree_skb(skb); 1096 return -EINVAL; 1097 } 1098 } 1099 1100 if (params->ie) { 1101 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len, 1102 GFP_KERNEL); 1103 if (sdata->u.ibss.ie) 1104 sdata->u.ibss.ie_len = params->ie_len; 1105 } 1106 1107 sdata->u.ibss.skb = skb; 1108 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; 1109 sdata->u.ibss.ibss_join_req = jiffies; 1110 1111 memcpy(sdata->u.ibss.ssid, params->ssid, IEEE80211_MAX_SSID_LEN); 1112 sdata->u.ibss.ssid_len = params->ssid_len; 1113 1114 mutex_unlock(&sdata->u.ibss.mtx); 1115 1116 mutex_lock(&sdata->local->mtx); 1117 ieee80211_recalc_idle(sdata->local); 1118 mutex_unlock(&sdata->local->mtx); 1119 1120 /* 1121 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is 1122 * reserved, but an HT STA shall protect HT transmissions as though 1123 * the HT Protection field were set to non-HT mixed mode. 1124 * 1125 * In an IBSS, the RIFS Mode field of the HT Operation element is 1126 * also reserved, but an HT STA shall operate as though this field 1127 * were set to 1. 1128 */ 1129 1130 sdata->vif.bss_conf.ht_operation_mode |= 1131 IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED 1132 | IEEE80211_HT_PARAM_RIFS_MODE; 1133 1134 changed |= BSS_CHANGED_HT; 1135 ieee80211_bss_info_change_notify(sdata, changed); 1136 1137 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 1138 1139 return 0; 1140} 1141 1142int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata) 1143{ 1144 struct sk_buff *skb; 1145 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1146 struct ieee80211_local *local = sdata->local; 1147 struct cfg80211_bss *cbss; 1148 u16 capability; 1149 int active_ibss; 1150 struct sta_info *sta; 1151 1152 mutex_lock(&sdata->u.ibss.mtx); 1153 1154 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; 1155 memset(sdata->u.ibss.bssid, 0, ETH_ALEN); 1156 sdata->u.ibss.ssid_len = 0; 1157 1158 active_ibss = ieee80211_sta_active_ibss(sdata); 1159 1160 if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) { 1161 capability = WLAN_CAPABILITY_IBSS; 1162 1163 if (ifibss->privacy) 1164 capability |= WLAN_CAPABILITY_PRIVACY; 1165 1166 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel, 1167 ifibss->bssid, ifibss->ssid, 1168 ifibss->ssid_len, WLAN_CAPABILITY_IBSS | 1169 WLAN_CAPABILITY_PRIVACY, 1170 capability); 1171 1172 if (cbss) { 1173 cfg80211_unlink_bss(local->hw.wiphy, cbss); 1174 cfg80211_put_bss(cbss); 1175 } 1176 } 1177 1178 sta_info_flush(sdata->local, sdata); 1179 1180 spin_lock_bh(&ifibss->incomplete_lock); 1181 while (!list_empty(&ifibss->incomplete_stations)) { 1182 sta = list_first_entry(&ifibss->incomplete_stations, 1183 struct sta_info, list); 1184 list_del(&sta->list); 1185 spin_unlock_bh(&ifibss->incomplete_lock); 1186 1187 sta_info_free(local, sta); 1188 spin_lock_bh(&ifibss->incomplete_lock); 1189 } 1190 spin_unlock_bh(&ifibss->incomplete_lock); 1191 1192 netif_carrier_off(sdata->dev); 1193 1194 /* remove beacon */ 1195 kfree(sdata->u.ibss.ie); 1196 skb = rcu_dereference_protected(sdata->u.ibss.presp, 1197 lockdep_is_held(&sdata->u.ibss.mtx)); 1198 RCU_INIT_POINTER(sdata->u.ibss.presp, NULL); 1199 sdata->vif.bss_conf.ibss_joined = false; 1200 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED | 1201 BSS_CHANGED_IBSS); 1202 synchronize_rcu(); 1203 kfree_skb(skb); 1204 1205 skb_queue_purge(&sdata->skb_queue); 1206 1207 del_timer_sync(&sdata->u.ibss.timer); 1208 1209 mutex_unlock(&sdata->u.ibss.mtx); 1210 1211 mutex_lock(&local->mtx); 1212 ieee80211_recalc_idle(sdata->local); 1213 mutex_unlock(&local->mtx); 1214 1215 return 0; 1216} 1217