ibss.c revision 5ea096c0c85e80335889539899af9a4717976e0b
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#include <asm/unaligned.h> 24 25#include "ieee80211_i.h" 26#include "driver-ops.h" 27#include "rate.h" 28 29#define IEEE80211_SCAN_INTERVAL (2 * HZ) 30#define IEEE80211_SCAN_INTERVAL_SLOW (15 * HZ) 31#define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ) 32 33#define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ) 34#define IEEE80211_IBSS_MERGE_DELAY 0x400000 35#define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ) 36 37#define IEEE80211_IBSS_MAX_STA_ENTRIES 128 38 39 40static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata, 41 struct ieee80211_mgmt *mgmt, 42 size_t len) 43{ 44 u16 auth_alg, auth_transaction, status_code; 45 46 if (len < 24 + 6) 47 return; 48 49 auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg); 50 auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction); 51 status_code = le16_to_cpu(mgmt->u.auth.status_code); 52 53 /* 54 * IEEE 802.11 standard does not require authentication in IBSS 55 * networks and most implementations do not seem to use it. 56 * However, try to reply to authentication attempts if someone 57 * has actually implemented this. 58 */ 59 if (auth_alg == WLAN_AUTH_OPEN && auth_transaction == 1) 60 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, NULL, 0, 61 sdata->u.ibss.bssid, NULL, 0, 0); 62} 63 64static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 65 const u8 *bssid, const int beacon_int, 66 struct ieee80211_channel *chan, 67 const u32 basic_rates, 68 const u16 capability, u64 tsf) 69{ 70 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 71 struct ieee80211_local *local = sdata->local; 72 int rates, i; 73 struct sk_buff *skb; 74 struct ieee80211_mgmt *mgmt; 75 u8 *pos; 76 struct ieee80211_supported_band *sband; 77 struct cfg80211_bss *bss; 78 u32 bss_change; 79 u8 supp_rates[IEEE80211_MAX_SUPP_RATES]; 80 81 /* Reset own TSF to allow time synchronization work. */ 82 drv_reset_tsf(local); 83 84 skb = ifibss->skb; 85 rcu_assign_pointer(ifibss->presp, NULL); 86 synchronize_rcu(); 87 skb->data = skb->head; 88 skb->len = 0; 89 skb_reset_tail_pointer(skb); 90 skb_reserve(skb, sdata->local->hw.extra_tx_headroom); 91 92 if (memcmp(ifibss->bssid, bssid, ETH_ALEN)) 93 sta_info_flush(sdata->local, sdata); 94 95 /* if merging, indicate to driver that we leave the old IBSS */ 96 if (sdata->vif.bss_conf.ibss_joined) { 97 sdata->vif.bss_conf.ibss_joined = false; 98 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IBSS); 99 } 100 101 memcpy(ifibss->bssid, bssid, ETH_ALEN); 102 103 sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0; 104 105 local->oper_channel = chan; 106 WARN_ON(!ieee80211_set_channel_type(local, sdata, NL80211_CHAN_NO_HT)); 107 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); 108 109 sband = local->hw.wiphy->bands[chan->band]; 110 111 /* build supported rates array */ 112 pos = supp_rates; 113 for (i = 0; i < sband->n_bitrates; i++) { 114 int rate = sband->bitrates[i].bitrate; 115 u8 basic = 0; 116 if (basic_rates & BIT(i)) 117 basic = 0x80; 118 *pos++ = basic | (u8) (rate / 5); 119 } 120 121 /* Build IBSS probe response */ 122 mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon)); 123 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon)); 124 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 125 IEEE80211_STYPE_PROBE_RESP); 126 memset(mgmt->da, 0xff, ETH_ALEN); 127 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 128 memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN); 129 mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int); 130 mgmt->u.beacon.timestamp = cpu_to_le64(tsf); 131 mgmt->u.beacon.capab_info = cpu_to_le16(capability); 132 133 pos = skb_put(skb, 2 + ifibss->ssid_len); 134 *pos++ = WLAN_EID_SSID; 135 *pos++ = ifibss->ssid_len; 136 memcpy(pos, ifibss->ssid, ifibss->ssid_len); 137 138 rates = sband->n_bitrates; 139 if (rates > 8) 140 rates = 8; 141 pos = skb_put(skb, 2 + rates); 142 *pos++ = WLAN_EID_SUPP_RATES; 143 *pos++ = rates; 144 memcpy(pos, supp_rates, rates); 145 146 if (sband->band == IEEE80211_BAND_2GHZ) { 147 pos = skb_put(skb, 2 + 1); 148 *pos++ = WLAN_EID_DS_PARAMS; 149 *pos++ = 1; 150 *pos++ = ieee80211_frequency_to_channel(chan->center_freq); 151 } 152 153 pos = skb_put(skb, 2 + 2); 154 *pos++ = WLAN_EID_IBSS_PARAMS; 155 *pos++ = 2; 156 /* FIX: set ATIM window based on scan results */ 157 *pos++ = 0; 158 *pos++ = 0; 159 160 if (sband->n_bitrates > 8) { 161 rates = sband->n_bitrates - 8; 162 pos = skb_put(skb, 2 + rates); 163 *pos++ = WLAN_EID_EXT_SUPP_RATES; 164 *pos++ = rates; 165 memcpy(pos, &supp_rates[8], rates); 166 } 167 168 if (ifibss->ie_len) 169 memcpy(skb_put(skb, ifibss->ie_len), 170 ifibss->ie, ifibss->ie_len); 171 172 rcu_assign_pointer(ifibss->presp, skb); 173 174 sdata->vif.bss_conf.beacon_int = beacon_int; 175 sdata->vif.bss_conf.basic_rates = basic_rates; 176 bss_change = BSS_CHANGED_BEACON_INT; 177 bss_change |= ieee80211_reset_erp_info(sdata); 178 bss_change |= BSS_CHANGED_BSSID; 179 bss_change |= BSS_CHANGED_BEACON; 180 bss_change |= BSS_CHANGED_BEACON_ENABLED; 181 bss_change |= BSS_CHANGED_BASIC_RATES; 182 bss_change |= BSS_CHANGED_IBSS; 183 sdata->vif.bss_conf.ibss_joined = true; 184 ieee80211_bss_info_change_notify(sdata, bss_change); 185 186 ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates); 187 188 ifibss->state = IEEE80211_IBSS_MLME_JOINED; 189 mod_timer(&ifibss->timer, 190 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 191 192 bss = cfg80211_inform_bss_frame(local->hw.wiphy, local->hw.conf.channel, 193 mgmt, skb->len, 0, GFP_KERNEL); 194 cfg80211_put_bss(bss); 195 cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL); 196} 197 198static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 199 struct ieee80211_bss *bss) 200{ 201 struct cfg80211_bss *cbss = 202 container_of((void *)bss, struct cfg80211_bss, priv); 203 struct ieee80211_supported_band *sband; 204 u32 basic_rates; 205 int i, j; 206 u16 beacon_int = cbss->beacon_interval; 207 208 if (beacon_int < 10) 209 beacon_int = 10; 210 211 sband = sdata->local->hw.wiphy->bands[cbss->channel->band]; 212 213 basic_rates = 0; 214 215 for (i = 0; i < bss->supp_rates_len; i++) { 216 int rate = (bss->supp_rates[i] & 0x7f) * 5; 217 bool is_basic = !!(bss->supp_rates[i] & 0x80); 218 219 for (j = 0; j < sband->n_bitrates; j++) { 220 if (sband->bitrates[j].bitrate == rate) { 221 if (is_basic) 222 basic_rates |= BIT(j); 223 break; 224 } 225 } 226 } 227 228 __ieee80211_sta_join_ibss(sdata, cbss->bssid, 229 beacon_int, 230 cbss->channel, 231 basic_rates, 232 cbss->capability, 233 cbss->tsf); 234} 235 236static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, 237 struct ieee80211_mgmt *mgmt, 238 size_t len, 239 struct ieee80211_rx_status *rx_status, 240 struct ieee802_11_elems *elems, 241 bool beacon) 242{ 243 struct ieee80211_local *local = sdata->local; 244 int freq; 245 struct cfg80211_bss *cbss; 246 struct ieee80211_bss *bss; 247 struct sta_info *sta; 248 struct ieee80211_channel *channel; 249 u64 beacon_timestamp, rx_timestamp; 250 u32 supp_rates = 0; 251 enum ieee80211_band band = rx_status->band; 252 253 if (elems->ds_params && elems->ds_params_len == 1) 254 freq = ieee80211_channel_to_frequency(elems->ds_params[0]); 255 else 256 freq = rx_status->freq; 257 258 channel = ieee80211_get_channel(local->hw.wiphy, freq); 259 260 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 261 return; 262 263 if (sdata->vif.type == NL80211_IFTYPE_ADHOC && elems->supp_rates && 264 memcmp(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) { 265 supp_rates = ieee80211_sta_get_rates(local, elems, band); 266 267 rcu_read_lock(); 268 269 sta = sta_info_get(sdata, mgmt->sa); 270 if (sta) { 271 u32 prev_rates; 272 273 prev_rates = sta->sta.supp_rates[band]; 274 /* make sure mandatory rates are always added */ 275 sta->sta.supp_rates[band] = supp_rates | 276 ieee80211_mandatory_rates(local, band); 277 278 if (sta->sta.supp_rates[band] != prev_rates) { 279#ifdef CONFIG_MAC80211_IBSS_DEBUG 280 printk(KERN_DEBUG "%s: updated supp_rates set " 281 "for %pM based on beacon/probe_response " 282 "(0x%x -> 0x%x)\n", 283 sdata->name, sta->sta.addr, 284 prev_rates, sta->sta.supp_rates[band]); 285#endif 286 rate_control_rate_init(sta); 287 } 288 rcu_read_unlock(); 289 } else { 290 rcu_read_unlock(); 291 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 292 supp_rates, GFP_KERNEL); 293 } 294 } 295 296 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems, 297 channel, beacon); 298 if (!bss) 299 return; 300 301 cbss = container_of((void *)bss, struct cfg80211_bss, priv); 302 303 /* was just updated in ieee80211_bss_info_update */ 304 beacon_timestamp = cbss->tsf; 305 306 /* check if we need to merge IBSS */ 307 308 /* we use a fixed BSSID */ 309 if (sdata->u.ibss.fixed_bssid) 310 goto put_bss; 311 312 /* not an IBSS */ 313 if (!(cbss->capability & WLAN_CAPABILITY_IBSS)) 314 goto put_bss; 315 316 /* different channel */ 317 if (cbss->channel != local->oper_channel) 318 goto put_bss; 319 320 /* different SSID */ 321 if (elems->ssid_len != sdata->u.ibss.ssid_len || 322 memcmp(elems->ssid, sdata->u.ibss.ssid, 323 sdata->u.ibss.ssid_len)) 324 goto put_bss; 325 326 /* same BSSID */ 327 if (memcmp(cbss->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) 328 goto put_bss; 329 330 if (rx_status->flag & RX_FLAG_TSFT) { 331 /* 332 * For correct IBSS merging we need mactime; since mactime is 333 * defined as the time the first data symbol of the frame hits 334 * the PHY, and the timestamp of the beacon is defined as "the 335 * time that the data symbol containing the first bit of the 336 * timestamp is transmitted to the PHY plus the transmitting 337 * STA's delays through its local PHY from the MAC-PHY 338 * interface to its interface with the WM" (802.11 11.1.2) 339 * - equals the time this bit arrives at the receiver - we have 340 * to take into account the offset between the two. 341 * 342 * E.g. at 1 MBit that means mactime is 192 usec earlier 343 * (=24 bytes * 8 usecs/byte) than the beacon timestamp. 344 */ 345 int rate; 346 347 if (rx_status->flag & RX_FLAG_HT) 348 rate = 65; /* TODO: HT rates */ 349 else 350 rate = local->hw.wiphy->bands[band]-> 351 bitrates[rx_status->rate_idx].bitrate; 352 353 rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate); 354 } else { 355 /* 356 * second best option: get current TSF 357 * (will return -1 if not supported) 358 */ 359 rx_timestamp = drv_get_tsf(local); 360 } 361 362#ifdef CONFIG_MAC80211_IBSS_DEBUG 363 printk(KERN_DEBUG "RX beacon SA=%pM BSSID=" 364 "%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n", 365 mgmt->sa, mgmt->bssid, 366 (unsigned long long)rx_timestamp, 367 (unsigned long long)beacon_timestamp, 368 (unsigned long long)(rx_timestamp - beacon_timestamp), 369 jiffies); 370#endif 371 372 /* give slow hardware some time to do the TSF sync */ 373 if (rx_timestamp < IEEE80211_IBSS_MERGE_DELAY) 374 goto put_bss; 375 376 if (beacon_timestamp > rx_timestamp) { 377#ifdef CONFIG_MAC80211_IBSS_DEBUG 378 printk(KERN_DEBUG "%s: beacon TSF higher than " 379 "local TSF - IBSS merge with BSSID %pM\n", 380 sdata->name, mgmt->bssid); 381#endif 382 ieee80211_sta_join_ibss(sdata, bss); 383 supp_rates = ieee80211_sta_get_rates(local, elems, band); 384 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 385 supp_rates, GFP_KERNEL); 386 } 387 388 put_bss: 389 ieee80211_rx_bss_put(local, bss); 390} 391 392/* 393 * Add a new IBSS station, will also be called by the RX code when, 394 * in IBSS mode, receiving a frame from a yet-unknown station, hence 395 * must be callable in atomic context. 396 */ 397struct sta_info *ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, 398 u8 *bssid,u8 *addr, u32 supp_rates, 399 gfp_t gfp) 400{ 401 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 402 struct ieee80211_local *local = sdata->local; 403 struct sta_info *sta; 404 int band = local->hw.conf.channel->band; 405 406 /* 407 * XXX: Consider removing the least recently used entry and 408 * allow new one to be added. 409 */ 410 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 411 if (net_ratelimit()) 412 printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n", 413 sdata->name, addr); 414 return NULL; 415 } 416 417 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) 418 return NULL; 419 420 if (compare_ether_addr(bssid, sdata->u.ibss.bssid)) 421 return NULL; 422 423#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 424 printk(KERN_DEBUG "%s: Adding new IBSS station %pM (dev=%s)\n", 425 wiphy_name(local->hw.wiphy), addr, sdata->name); 426#endif 427 428 sta = sta_info_alloc(sdata, addr, gfp); 429 if (!sta) 430 return NULL; 431 432 set_sta_flags(sta, WLAN_STA_AUTHORIZED); 433 434 /* make sure mandatory rates are always added */ 435 sta->sta.supp_rates[band] = supp_rates | 436 ieee80211_mandatory_rates(local, band); 437 438 rate_control_rate_init(sta); 439 440 /* If it fails, maybe we raced another insertion? */ 441 if (sta_info_insert(sta)) 442 return sta_info_get(sdata, addr); 443 return sta; 444} 445 446static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata) 447{ 448 struct ieee80211_local *local = sdata->local; 449 int active = 0; 450 struct sta_info *sta; 451 452 rcu_read_lock(); 453 454 list_for_each_entry_rcu(sta, &local->sta_list, list) { 455 if (sta->sdata == sdata && 456 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL, 457 jiffies)) { 458 active++; 459 break; 460 } 461 } 462 463 rcu_read_unlock(); 464 465 return active; 466} 467 468/* 469 * This function is called with state == IEEE80211_IBSS_MLME_JOINED 470 */ 471 472static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata) 473{ 474 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 475 476 mod_timer(&ifibss->timer, 477 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 478 479 ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT); 480 481 if (time_before(jiffies, ifibss->last_scan_completed + 482 IEEE80211_IBSS_MERGE_INTERVAL)) 483 return; 484 485 if (ieee80211_sta_active_ibss(sdata)) 486 return; 487 488 if (ifibss->fixed_channel) 489 return; 490 491 printk(KERN_DEBUG "%s: No active IBSS STAs - trying to scan for other " 492 "IBSS networks with same SSID (merge)\n", sdata->name); 493 494 ieee80211_request_internal_scan(sdata, 495 ifibss->ssid, ifibss->ssid_len, 496 ifibss->fixed_channel ? ifibss->channel : NULL); 497} 498 499static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata) 500{ 501 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 502 struct ieee80211_local *local = sdata->local; 503 struct ieee80211_supported_band *sband; 504 u8 bssid[ETH_ALEN]; 505 u16 capability; 506 int i; 507 508 if (ifibss->fixed_bssid) { 509 memcpy(bssid, ifibss->bssid, ETH_ALEN); 510 } else { 511 /* Generate random, not broadcast, locally administered BSSID. Mix in 512 * own MAC address to make sure that devices that do not have proper 513 * random number generator get different BSSID. */ 514 get_random_bytes(bssid, ETH_ALEN); 515 for (i = 0; i < ETH_ALEN; i++) 516 bssid[i] ^= sdata->vif.addr[i]; 517 bssid[0] &= ~0x01; 518 bssid[0] |= 0x02; 519 } 520 521 printk(KERN_DEBUG "%s: Creating new IBSS network, BSSID %pM\n", 522 sdata->name, bssid); 523 524 sband = local->hw.wiphy->bands[ifibss->channel->band]; 525 526 capability = WLAN_CAPABILITY_IBSS; 527 528 if (ifibss->privacy) 529 capability |= WLAN_CAPABILITY_PRIVACY; 530 else 531 sdata->drop_unencrypted = 0; 532 533 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int, 534 ifibss->channel, ifibss->basic_rates, 535 capability, 0); 536} 537 538/* 539 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH 540 */ 541 542static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata) 543{ 544 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 545 struct ieee80211_local *local = sdata->local; 546 struct cfg80211_bss *cbss; 547 struct ieee80211_channel *chan = NULL; 548 const u8 *bssid = NULL; 549 int active_ibss; 550 u16 capability; 551 552 active_ibss = ieee80211_sta_active_ibss(sdata); 553#ifdef CONFIG_MAC80211_IBSS_DEBUG 554 printk(KERN_DEBUG "%s: sta_find_ibss (active_ibss=%d)\n", 555 sdata->name, active_ibss); 556#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 557 558 if (active_ibss) 559 return; 560 561 capability = WLAN_CAPABILITY_IBSS; 562 if (ifibss->privacy) 563 capability |= WLAN_CAPABILITY_PRIVACY; 564 if (ifibss->fixed_bssid) 565 bssid = ifibss->bssid; 566 if (ifibss->fixed_channel) 567 chan = ifibss->channel; 568 if (!is_zero_ether_addr(ifibss->bssid)) 569 bssid = ifibss->bssid; 570 cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid, 571 ifibss->ssid, ifibss->ssid_len, 572 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY, 573 capability); 574 575 if (cbss) { 576 struct ieee80211_bss *bss; 577 578 bss = (void *)cbss->priv; 579#ifdef CONFIG_MAC80211_IBSS_DEBUG 580 printk(KERN_DEBUG " sta_find_ibss: selected %pM current " 581 "%pM\n", cbss->bssid, ifibss->bssid); 582#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 583 584 printk(KERN_DEBUG "%s: Selected IBSS BSSID %pM" 585 " based on configured SSID\n", 586 sdata->name, cbss->bssid); 587 588 ieee80211_sta_join_ibss(sdata, bss); 589 ieee80211_rx_bss_put(local, bss); 590 return; 591 } 592 593#ifdef CONFIG_MAC80211_IBSS_DEBUG 594 printk(KERN_DEBUG " did not try to join ibss\n"); 595#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 596 597 /* Selected IBSS not found in current scan results - try to scan */ 598 if (time_after(jiffies, ifibss->last_scan_completed + 599 IEEE80211_SCAN_INTERVAL)) { 600 printk(KERN_DEBUG "%s: Trigger new scan to find an IBSS to " 601 "join\n", sdata->name); 602 603 ieee80211_request_internal_scan(sdata, 604 ifibss->ssid, ifibss->ssid_len, 605 ifibss->fixed_channel ? ifibss->channel : NULL); 606 } else { 607 int interval = IEEE80211_SCAN_INTERVAL; 608 609 if (time_after(jiffies, ifibss->ibss_join_req + 610 IEEE80211_IBSS_JOIN_TIMEOUT)) { 611 if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) { 612 ieee80211_sta_create_ibss(sdata); 613 return; 614 } 615 printk(KERN_DEBUG "%s: IBSS not allowed on" 616 " %d MHz\n", sdata->name, 617 local->hw.conf.channel->center_freq); 618 619 /* No IBSS found - decrease scan interval and continue 620 * scanning. */ 621 interval = IEEE80211_SCAN_INTERVAL_SLOW; 622 } 623 624 mod_timer(&ifibss->timer, 625 round_jiffies(jiffies + interval)); 626 } 627} 628 629static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata, 630 struct ieee80211_mgmt *mgmt, 631 size_t len) 632{ 633 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 634 struct ieee80211_local *local = sdata->local; 635 int tx_last_beacon; 636 struct sk_buff *skb; 637 struct ieee80211_mgmt *resp; 638 u8 *pos, *end; 639 640 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED || 641 len < 24 + 2 || !ifibss->presp) 642 return; 643 644 tx_last_beacon = drv_tx_last_beacon(local); 645 646#ifdef CONFIG_MAC80211_IBSS_DEBUG 647 printk(KERN_DEBUG "%s: RX ProbeReq SA=%pM DA=%pM BSSID=%pM" 648 " (tx_last_beacon=%d)\n", 649 sdata->name, mgmt->sa, mgmt->da, 650 mgmt->bssid, tx_last_beacon); 651#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 652 653 if (!tx_last_beacon) 654 return; 655 656 if (memcmp(mgmt->bssid, ifibss->bssid, ETH_ALEN) != 0 && 657 memcmp(mgmt->bssid, "\xff\xff\xff\xff\xff\xff", ETH_ALEN) != 0) 658 return; 659 660 end = ((u8 *) mgmt) + len; 661 pos = mgmt->u.probe_req.variable; 662 if (pos[0] != WLAN_EID_SSID || 663 pos + 2 + pos[1] > end) { 664#ifdef CONFIG_MAC80211_IBSS_DEBUG 665 printk(KERN_DEBUG "%s: Invalid SSID IE in ProbeReq " 666 "from %pM\n", 667 sdata->name, mgmt->sa); 668#endif 669 return; 670 } 671 if (pos[1] != 0 && 672 (pos[1] != ifibss->ssid_len || 673 memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) { 674 /* Ignore ProbeReq for foreign SSID */ 675 return; 676 } 677 678 /* Reply with ProbeResp */ 679 skb = skb_copy(ifibss->presp, GFP_KERNEL); 680 if (!skb) 681 return; 682 683 resp = (struct ieee80211_mgmt *) skb->data; 684 memcpy(resp->da, mgmt->sa, ETH_ALEN); 685#ifdef CONFIG_MAC80211_IBSS_DEBUG 686 printk(KERN_DEBUG "%s: Sending ProbeResp to %pM\n", 687 sdata->name, resp->da); 688#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 689 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 690 ieee80211_tx_skb(sdata, skb); 691} 692 693static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata, 694 struct ieee80211_mgmt *mgmt, 695 size_t len, 696 struct ieee80211_rx_status *rx_status) 697{ 698 size_t baselen; 699 struct ieee802_11_elems elems; 700 701 if (memcmp(mgmt->da, sdata->vif.addr, ETH_ALEN)) 702 return; /* ignore ProbeResp to foreign address */ 703 704 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt; 705 if (baselen > len) 706 return; 707 708 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen, 709 &elems); 710 711 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false); 712} 713 714static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 715 struct ieee80211_mgmt *mgmt, 716 size_t len, 717 struct ieee80211_rx_status *rx_status) 718{ 719 size_t baselen; 720 struct ieee802_11_elems elems; 721 722 /* Process beacon from the current BSS */ 723 baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt; 724 if (baselen > len) 725 return; 726 727 ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems); 728 729 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true); 730} 731 732void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata, 733 struct sk_buff *skb) 734{ 735 struct ieee80211_rx_status *rx_status; 736 struct ieee80211_mgmt *mgmt; 737 u16 fc; 738 739 rx_status = IEEE80211_SKB_RXCB(skb); 740 mgmt = (struct ieee80211_mgmt *) skb->data; 741 fc = le16_to_cpu(mgmt->frame_control); 742 743 switch (fc & IEEE80211_FCTL_STYPE) { 744 case IEEE80211_STYPE_PROBE_REQ: 745 ieee80211_rx_mgmt_probe_req(sdata, mgmt, skb->len); 746 break; 747 case IEEE80211_STYPE_PROBE_RESP: 748 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len, 749 rx_status); 750 break; 751 case IEEE80211_STYPE_BEACON: 752 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len, 753 rx_status); 754 break; 755 case IEEE80211_STYPE_AUTH: 756 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len); 757 break; 758 } 759} 760 761void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata) 762{ 763 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 764 765 if (!test_and_clear_bit(IEEE80211_IBSS_REQ_RUN, &ifibss->request)) 766 return; 767 768 switch (ifibss->state) { 769 case IEEE80211_IBSS_MLME_SEARCH: 770 ieee80211_sta_find_ibss(sdata); 771 break; 772 case IEEE80211_IBSS_MLME_JOINED: 773 ieee80211_sta_merge_ibss(sdata); 774 break; 775 default: 776 WARN_ON(1); 777 break; 778 } 779} 780 781static void ieee80211_queue_ibss_work(struct ieee80211_sub_if_data *sdata) 782{ 783 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 784 struct ieee80211_local *local = sdata->local; 785 786 set_bit(IEEE80211_IBSS_REQ_RUN, &ifibss->request); 787 ieee80211_queue_work(&local->hw, &sdata->work); 788} 789 790static void ieee80211_ibss_timer(unsigned long data) 791{ 792 struct ieee80211_sub_if_data *sdata = 793 (struct ieee80211_sub_if_data *) data; 794 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 795 struct ieee80211_local *local = sdata->local; 796 797 if (local->quiescing) { 798 ifibss->timer_running = true; 799 return; 800 } 801 802 ieee80211_queue_ibss_work(sdata); 803} 804 805#ifdef CONFIG_PM 806void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata) 807{ 808 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 809 810 if (del_timer_sync(&ifibss->timer)) 811 ifibss->timer_running = true; 812} 813 814void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata) 815{ 816 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 817 818 if (ifibss->timer_running) { 819 add_timer(&ifibss->timer); 820 ifibss->timer_running = false; 821 } 822} 823#endif 824 825void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata) 826{ 827 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 828 829 setup_timer(&ifibss->timer, ieee80211_ibss_timer, 830 (unsigned long) sdata); 831} 832 833/* scan finished notification */ 834void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local) 835{ 836 struct ieee80211_sub_if_data *sdata; 837 838 mutex_lock(&local->iflist_mtx); 839 list_for_each_entry(sdata, &local->interfaces, list) { 840 if (!ieee80211_sdata_running(sdata)) 841 continue; 842 if (sdata->vif.type != NL80211_IFTYPE_ADHOC) 843 continue; 844 if (!sdata->u.ibss.ssid_len) 845 continue; 846 sdata->u.ibss.last_scan_completed = jiffies; 847 ieee80211_queue_ibss_work(sdata); 848 } 849 mutex_unlock(&local->iflist_mtx); 850} 851 852int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata, 853 struct cfg80211_ibss_params *params) 854{ 855 struct sk_buff *skb; 856 857 if (params->bssid) { 858 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN); 859 sdata->u.ibss.fixed_bssid = true; 860 } else 861 sdata->u.ibss.fixed_bssid = false; 862 863 sdata->u.ibss.privacy = params->privacy; 864 sdata->u.ibss.basic_rates = params->basic_rates; 865 866 sdata->vif.bss_conf.beacon_int = params->beacon_interval; 867 868 sdata->u.ibss.channel = params->channel; 869 sdata->u.ibss.fixed_channel = params->channel_fixed; 870 871 /* fix ourselves to that channel now already */ 872 if (params->channel_fixed) { 873 sdata->local->oper_channel = params->channel; 874 WARN_ON(!ieee80211_set_channel_type(sdata->local, sdata, 875 NL80211_CHAN_NO_HT)); 876 } 877 878 if (params->ie) { 879 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len, 880 GFP_KERNEL); 881 if (sdata->u.ibss.ie) 882 sdata->u.ibss.ie_len = params->ie_len; 883 } 884 885 skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom + 886 36 /* bitrates */ + 887 34 /* SSID */ + 888 3 /* DS params */ + 889 4 /* IBSS params */ + 890 params->ie_len); 891 if (!skb) 892 return -ENOMEM; 893 894 sdata->u.ibss.skb = skb; 895 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; 896 sdata->u.ibss.ibss_join_req = jiffies; 897 898 memcpy(sdata->u.ibss.ssid, params->ssid, IEEE80211_MAX_SSID_LEN); 899 900 /* 901 * The ssid_len setting below is used to see whether 902 * we are active, and we need all other settings 903 * before that may get visible. 904 */ 905 mb(); 906 907 sdata->u.ibss.ssid_len = params->ssid_len; 908 909 ieee80211_recalc_idle(sdata->local); 910 911 set_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request); 912 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 913 914 return 0; 915} 916 917int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata) 918{ 919 struct sk_buff *skb; 920 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 921 struct ieee80211_local *local = sdata->local; 922 struct cfg80211_bss *cbss; 923 u16 capability; 924 int active_ibss = 0; 925 926 active_ibss = ieee80211_sta_active_ibss(sdata); 927 928 if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) { 929 capability = WLAN_CAPABILITY_IBSS; 930 931 if (ifibss->privacy) 932 capability |= WLAN_CAPABILITY_PRIVACY; 933 934 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel, 935 ifibss->bssid, ifibss->ssid, 936 ifibss->ssid_len, WLAN_CAPABILITY_IBSS | 937 WLAN_CAPABILITY_PRIVACY, 938 capability); 939 940 if (cbss) { 941 cfg80211_unlink_bss(local->hw.wiphy, cbss); 942 cfg80211_put_bss(cbss); 943 } 944 } 945 946 del_timer_sync(&sdata->u.ibss.timer); 947 clear_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request); 948 cancel_work_sync(&sdata->work); 949 clear_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request); 950 951 sta_info_flush(sdata->local, sdata); 952 953 /* remove beacon */ 954 kfree(sdata->u.ibss.ie); 955 skb = sdata->u.ibss.presp; 956 rcu_assign_pointer(sdata->u.ibss.presp, NULL); 957 sdata->vif.bss_conf.ibss_joined = false; 958 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED | 959 BSS_CHANGED_IBSS); 960 synchronize_rcu(); 961 kfree_skb(skb); 962 963 skb_queue_purge(&sdata->skb_queue); 964 memset(sdata->u.ibss.bssid, 0, ETH_ALEN); 965 sdata->u.ibss.ssid_len = 0; 966 967 ieee80211_recalc_idle(sdata->local); 968 969 return 0; 970} 971