ibss.c revision 34e895075e21be3e21e71d6317440d1ee7969ad0
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/if_ether.h> 17#include <linux/skbuff.h> 18#include <linux/if_arp.h> 19#include <linux/etherdevice.h> 20#include <linux/rtnetlink.h> 21#include <net/mac80211.h> 22#include <asm/unaligned.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_MERGE_DELAY 0x400000 34#define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ) 35 36#define IEEE80211_IBSS_MAX_STA_ENTRIES 128 37 38 39static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata, 40 struct ieee80211_mgmt *mgmt, 41 size_t len) 42{ 43 u16 auth_alg, auth_transaction, status_code; 44 45 if (len < 24 + 6) 46 return; 47 48 auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg); 49 auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction); 50 status_code = le16_to_cpu(mgmt->u.auth.status_code); 51 52 /* 53 * IEEE 802.11 standard does not require authentication in IBSS 54 * networks and most implementations do not seem to use it. 55 * However, try to reply to authentication attempts if someone 56 * has actually implemented this. 57 */ 58 if (auth_alg == WLAN_AUTH_OPEN && auth_transaction == 1) 59 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, NULL, 0, 60 sdata->u.ibss.bssid, NULL, 0, 0); 61} 62 63static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 64 const u8 *bssid, const int beacon_int, 65 struct ieee80211_channel *chan, 66 const u32 basic_rates, 67 const u16 capability, u64 tsf) 68{ 69 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 70 struct ieee80211_local *local = sdata->local; 71 int rates, i; 72 struct sk_buff *skb; 73 struct ieee80211_mgmt *mgmt; 74 u8 *pos; 75 struct ieee80211_supported_band *sband; 76 struct cfg80211_bss *bss; 77 u32 bss_change; 78 u8 supp_rates[IEEE80211_MAX_SUPP_RATES]; 79 80 /* Reset own TSF to allow time synchronization work. */ 81 drv_reset_tsf(local); 82 83 skb = ifibss->skb; 84 rcu_assign_pointer(ifibss->presp, NULL); 85 synchronize_rcu(); 86 skb->data = skb->head; 87 skb->len = 0; 88 skb_reset_tail_pointer(skb); 89 skb_reserve(skb, sdata->local->hw.extra_tx_headroom); 90 91 if (memcmp(ifibss->bssid, bssid, ETH_ALEN)) 92 sta_info_flush(sdata->local, sdata); 93 94 memcpy(ifibss->bssid, bssid, ETH_ALEN); 95 96 sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0; 97 98 local->oper_channel = chan; 99 local->oper_channel_type = NL80211_CHAN_NO_HT; 100 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); 101 102 sband = local->hw.wiphy->bands[chan->band]; 103 104 /* build supported rates array */ 105 pos = supp_rates; 106 for (i = 0; i < sband->n_bitrates; i++) { 107 int rate = sband->bitrates[i].bitrate; 108 u8 basic = 0; 109 if (basic_rates & BIT(i)) 110 basic = 0x80; 111 *pos++ = basic | (u8) (rate / 5); 112 } 113 114 /* Build IBSS probe response */ 115 mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon)); 116 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon)); 117 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 118 IEEE80211_STYPE_PROBE_RESP); 119 memset(mgmt->da, 0xff, ETH_ALEN); 120 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 121 memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN); 122 mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int); 123 mgmt->u.beacon.timestamp = cpu_to_le64(tsf); 124 mgmt->u.beacon.capab_info = cpu_to_le16(capability); 125 126 pos = skb_put(skb, 2 + ifibss->ssid_len); 127 *pos++ = WLAN_EID_SSID; 128 *pos++ = ifibss->ssid_len; 129 memcpy(pos, ifibss->ssid, ifibss->ssid_len); 130 131 rates = sband->n_bitrates; 132 if (rates > 8) 133 rates = 8; 134 pos = skb_put(skb, 2 + rates); 135 *pos++ = WLAN_EID_SUPP_RATES; 136 *pos++ = rates; 137 memcpy(pos, supp_rates, rates); 138 139 if (sband->band == IEEE80211_BAND_2GHZ) { 140 pos = skb_put(skb, 2 + 1); 141 *pos++ = WLAN_EID_DS_PARAMS; 142 *pos++ = 1; 143 *pos++ = ieee80211_frequency_to_channel(chan->center_freq); 144 } 145 146 pos = skb_put(skb, 2 + 2); 147 *pos++ = WLAN_EID_IBSS_PARAMS; 148 *pos++ = 2; 149 /* FIX: set ATIM window based on scan results */ 150 *pos++ = 0; 151 *pos++ = 0; 152 153 if (sband->n_bitrates > 8) { 154 rates = sband->n_bitrates - 8; 155 pos = skb_put(skb, 2 + rates); 156 *pos++ = WLAN_EID_EXT_SUPP_RATES; 157 *pos++ = rates; 158 memcpy(pos, &supp_rates[8], rates); 159 } 160 161 if (ifibss->ie_len) 162 memcpy(skb_put(skb, ifibss->ie_len), 163 ifibss->ie, ifibss->ie_len); 164 165 rcu_assign_pointer(ifibss->presp, skb); 166 167 sdata->vif.bss_conf.beacon_int = beacon_int; 168 bss_change = BSS_CHANGED_BEACON_INT; 169 bss_change |= ieee80211_reset_erp_info(sdata); 170 bss_change |= BSS_CHANGED_BSSID; 171 bss_change |= BSS_CHANGED_BEACON; 172 bss_change |= BSS_CHANGED_BEACON_ENABLED; 173 ieee80211_bss_info_change_notify(sdata, bss_change); 174 175 ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates); 176 177 ifibss->state = IEEE80211_IBSS_MLME_JOINED; 178 mod_timer(&ifibss->timer, 179 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 180 181 bss = cfg80211_inform_bss_frame(local->hw.wiphy, local->hw.conf.channel, 182 mgmt, skb->len, 0, GFP_KERNEL); 183 cfg80211_put_bss(bss); 184 cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL); 185} 186 187static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 188 struct ieee80211_bss *bss) 189{ 190 struct cfg80211_bss *cbss = 191 container_of((void *)bss, struct cfg80211_bss, priv); 192 struct ieee80211_supported_band *sband; 193 u32 basic_rates; 194 int i, j; 195 u16 beacon_int = cbss->beacon_interval; 196 197 if (beacon_int < 10) 198 beacon_int = 10; 199 200 sband = sdata->local->hw.wiphy->bands[cbss->channel->band]; 201 202 basic_rates = 0; 203 204 for (i = 0; i < bss->supp_rates_len; i++) { 205 int rate = (bss->supp_rates[i] & 0x7f) * 5; 206 bool is_basic = !!(bss->supp_rates[i] & 0x80); 207 208 for (j = 0; j < sband->n_bitrates; j++) { 209 if (sband->bitrates[j].bitrate == rate) { 210 if (is_basic) 211 basic_rates |= BIT(j); 212 break; 213 } 214 } 215 } 216 217 __ieee80211_sta_join_ibss(sdata, cbss->bssid, 218 beacon_int, 219 cbss->channel, 220 basic_rates, 221 cbss->capability, 222 cbss->tsf); 223} 224 225static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, 226 struct ieee80211_mgmt *mgmt, 227 size_t len, 228 struct ieee80211_rx_status *rx_status, 229 struct ieee802_11_elems *elems, 230 bool beacon) 231{ 232 struct ieee80211_local *local = sdata->local; 233 int freq; 234 struct cfg80211_bss *cbss; 235 struct ieee80211_bss *bss; 236 struct sta_info *sta; 237 struct ieee80211_channel *channel; 238 u64 beacon_timestamp, rx_timestamp; 239 u32 supp_rates = 0; 240 enum ieee80211_band band = rx_status->band; 241 242 if (elems->ds_params && elems->ds_params_len == 1) 243 freq = ieee80211_channel_to_frequency(elems->ds_params[0]); 244 else 245 freq = rx_status->freq; 246 247 channel = ieee80211_get_channel(local->hw.wiphy, freq); 248 249 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 250 return; 251 252 if (sdata->vif.type == NL80211_IFTYPE_ADHOC && elems->supp_rates && 253 memcmp(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) { 254 supp_rates = ieee80211_sta_get_rates(local, elems, band); 255 256 rcu_read_lock(); 257 258 sta = sta_info_get(sdata, mgmt->sa); 259 if (sta) { 260 u32 prev_rates; 261 262 prev_rates = sta->sta.supp_rates[band]; 263 /* make sure mandatory rates are always added */ 264 sta->sta.supp_rates[band] = supp_rates | 265 ieee80211_mandatory_rates(local, band); 266 267#ifdef CONFIG_MAC80211_IBSS_DEBUG 268 if (sta->sta.supp_rates[band] != prev_rates) 269 printk(KERN_DEBUG "%s: updated supp_rates set " 270 "for %pM based on beacon info (0x%llx | " 271 "0x%llx -> 0x%llx)\n", 272 sdata->name, 273 sta->sta.addr, 274 (unsigned long long) prev_rates, 275 (unsigned long long) supp_rates, 276 (unsigned long long) sta->sta.supp_rates[band]); 277#endif 278 rcu_read_unlock(); 279 } else { 280 rcu_read_unlock(); 281 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 282 supp_rates, GFP_KERNEL); 283 } 284 } 285 286 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems, 287 channel, beacon); 288 if (!bss) 289 return; 290 291 cbss = container_of((void *)bss, struct cfg80211_bss, priv); 292 293 /* was just updated in ieee80211_bss_info_update */ 294 beacon_timestamp = cbss->tsf; 295 296 /* check if we need to merge IBSS */ 297 298 /* we use a fixed BSSID */ 299 if (sdata->u.ibss.fixed_bssid) 300 goto put_bss; 301 302 /* not an IBSS */ 303 if (!(cbss->capability & WLAN_CAPABILITY_IBSS)) 304 goto put_bss; 305 306 /* different channel */ 307 if (cbss->channel != local->oper_channel) 308 goto put_bss; 309 310 /* different SSID */ 311 if (elems->ssid_len != sdata->u.ibss.ssid_len || 312 memcmp(elems->ssid, sdata->u.ibss.ssid, 313 sdata->u.ibss.ssid_len)) 314 goto put_bss; 315 316 /* same BSSID */ 317 if (memcmp(cbss->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) 318 goto put_bss; 319 320 if (rx_status->flag & RX_FLAG_TSFT) { 321 /* 322 * For correct IBSS merging we need mactime; since mactime is 323 * defined as the time the first data symbol of the frame hits 324 * the PHY, and the timestamp of the beacon is defined as "the 325 * time that the data symbol containing the first bit of the 326 * timestamp is transmitted to the PHY plus the transmitting 327 * STA's delays through its local PHY from the MAC-PHY 328 * interface to its interface with the WM" (802.11 11.1.2) 329 * - equals the time this bit arrives at the receiver - we have 330 * to take into account the offset between the two. 331 * 332 * E.g. at 1 MBit that means mactime is 192 usec earlier 333 * (=24 bytes * 8 usecs/byte) than the beacon timestamp. 334 */ 335 int rate; 336 337 if (rx_status->flag & RX_FLAG_HT) 338 rate = 65; /* TODO: HT rates */ 339 else 340 rate = local->hw.wiphy->bands[band]-> 341 bitrates[rx_status->rate_idx].bitrate; 342 343 rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate); 344 } else { 345 /* 346 * second best option: get current TSF 347 * (will return -1 if not supported) 348 */ 349 rx_timestamp = drv_get_tsf(local); 350 } 351 352#ifdef CONFIG_MAC80211_IBSS_DEBUG 353 printk(KERN_DEBUG "RX beacon SA=%pM BSSID=" 354 "%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n", 355 mgmt->sa, mgmt->bssid, 356 (unsigned long long)rx_timestamp, 357 (unsigned long long)beacon_timestamp, 358 (unsigned long long)(rx_timestamp - beacon_timestamp), 359 jiffies); 360#endif 361 362 /* give slow hardware some time to do the TSF sync */ 363 if (rx_timestamp < IEEE80211_IBSS_MERGE_DELAY) 364 goto put_bss; 365 366 if (beacon_timestamp > rx_timestamp) { 367#ifdef CONFIG_MAC80211_IBSS_DEBUG 368 printk(KERN_DEBUG "%s: beacon TSF higher than " 369 "local TSF - IBSS merge with BSSID %pM\n", 370 sdata->name, mgmt->bssid); 371#endif 372 ieee80211_sta_join_ibss(sdata, bss); 373 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 374 supp_rates, GFP_KERNEL); 375 } 376 377 put_bss: 378 ieee80211_rx_bss_put(local, bss); 379} 380 381/* 382 * Add a new IBSS station, will also be called by the RX code when, 383 * in IBSS mode, receiving a frame from a yet-unknown station, hence 384 * must be callable in atomic context. 385 */ 386struct sta_info *ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, 387 u8 *bssid,u8 *addr, u32 supp_rates, 388 gfp_t gfp) 389{ 390 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 391 struct ieee80211_local *local = sdata->local; 392 struct sta_info *sta; 393 int band = local->hw.conf.channel->band; 394 395 /* 396 * XXX: Consider removing the least recently used entry and 397 * allow new one to be added. 398 */ 399 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 400 if (net_ratelimit()) 401 printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n", 402 sdata->name, addr); 403 return NULL; 404 } 405 406 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) 407 return NULL; 408 409 if (compare_ether_addr(bssid, sdata->u.ibss.bssid)) 410 return NULL; 411 412#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 413 printk(KERN_DEBUG "%s: Adding new IBSS station %pM (dev=%s)\n", 414 wiphy_name(local->hw.wiphy), addr, sdata->name); 415#endif 416 417 sta = sta_info_alloc(sdata, addr, gfp); 418 if (!sta) 419 return NULL; 420 421 set_sta_flags(sta, WLAN_STA_AUTHORIZED); 422 423 /* make sure mandatory rates are always added */ 424 sta->sta.supp_rates[band] = supp_rates | 425 ieee80211_mandatory_rates(local, band); 426 427 rate_control_rate_init(sta); 428 429 /* If it fails, maybe we raced another insertion? */ 430 if (sta_info_insert(sta)) 431 return sta_info_get(sdata, addr); 432 return sta; 433} 434 435static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata) 436{ 437 struct ieee80211_local *local = sdata->local; 438 int active = 0; 439 struct sta_info *sta; 440 441 rcu_read_lock(); 442 443 list_for_each_entry_rcu(sta, &local->sta_list, list) { 444 if (sta->sdata == sdata && 445 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL, 446 jiffies)) { 447 active++; 448 break; 449 } 450 } 451 452 rcu_read_unlock(); 453 454 return active; 455} 456 457/* 458 * This function is called with state == IEEE80211_IBSS_MLME_JOINED 459 */ 460 461static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata) 462{ 463 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 464 465 mod_timer(&ifibss->timer, 466 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 467 468 ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT); 469 470 if (time_before(jiffies, ifibss->last_scan_completed + 471 IEEE80211_IBSS_MERGE_INTERVAL)) 472 return; 473 474 if (ieee80211_sta_active_ibss(sdata)) 475 return; 476 477 if (ifibss->fixed_channel) 478 return; 479 480 printk(KERN_DEBUG "%s: No active IBSS STAs - trying to scan for other " 481 "IBSS networks with same SSID (merge)\n", sdata->name); 482 483 ieee80211_request_internal_scan(sdata, ifibss->ssid, ifibss->ssid_len); 484} 485 486static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata) 487{ 488 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 489 struct ieee80211_local *local = sdata->local; 490 struct ieee80211_supported_band *sband; 491 u8 bssid[ETH_ALEN]; 492 u16 capability; 493 int i; 494 495 if (ifibss->fixed_bssid) { 496 memcpy(bssid, ifibss->bssid, ETH_ALEN); 497 } else { 498 /* Generate random, not broadcast, locally administered BSSID. Mix in 499 * own MAC address to make sure that devices that do not have proper 500 * random number generator get different BSSID. */ 501 get_random_bytes(bssid, ETH_ALEN); 502 for (i = 0; i < ETH_ALEN; i++) 503 bssid[i] ^= sdata->vif.addr[i]; 504 bssid[0] &= ~0x01; 505 bssid[0] |= 0x02; 506 } 507 508 printk(KERN_DEBUG "%s: Creating new IBSS network, BSSID %pM\n", 509 sdata->name, bssid); 510 511 sband = local->hw.wiphy->bands[ifibss->channel->band]; 512 513 capability = WLAN_CAPABILITY_IBSS; 514 515 if (ifibss->privacy) 516 capability |= WLAN_CAPABILITY_PRIVACY; 517 else 518 sdata->drop_unencrypted = 0; 519 520 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int, 521 ifibss->channel, 3, /* first two are basic */ 522 capability, 0); 523} 524 525/* 526 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH 527 */ 528 529static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata) 530{ 531 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 532 struct ieee80211_local *local = sdata->local; 533 struct cfg80211_bss *cbss; 534 struct ieee80211_channel *chan = NULL; 535 const u8 *bssid = NULL; 536 int active_ibss; 537 u16 capability; 538 539 active_ibss = ieee80211_sta_active_ibss(sdata); 540#ifdef CONFIG_MAC80211_IBSS_DEBUG 541 printk(KERN_DEBUG "%s: sta_find_ibss (active_ibss=%d)\n", 542 sdata->name, active_ibss); 543#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 544 545 if (active_ibss) 546 return; 547 548 capability = WLAN_CAPABILITY_IBSS; 549 if (ifibss->privacy) 550 capability |= WLAN_CAPABILITY_PRIVACY; 551 if (ifibss->fixed_bssid) 552 bssid = ifibss->bssid; 553 if (ifibss->fixed_channel) 554 chan = ifibss->channel; 555 if (!is_zero_ether_addr(ifibss->bssid)) 556 bssid = ifibss->bssid; 557 cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid, 558 ifibss->ssid, ifibss->ssid_len, 559 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY, 560 capability); 561 562 if (cbss) { 563 struct ieee80211_bss *bss; 564 565 bss = (void *)cbss->priv; 566#ifdef CONFIG_MAC80211_IBSS_DEBUG 567 printk(KERN_DEBUG " sta_find_ibss: selected %pM current " 568 "%pM\n", cbss->bssid, ifibss->bssid); 569#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 570 571 printk(KERN_DEBUG "%s: Selected IBSS BSSID %pM" 572 " based on configured SSID\n", 573 sdata->name, cbss->bssid); 574 575 ieee80211_sta_join_ibss(sdata, bss); 576 ieee80211_rx_bss_put(local, bss); 577 return; 578 } 579 580#ifdef CONFIG_MAC80211_IBSS_DEBUG 581 printk(KERN_DEBUG " did not try to join ibss\n"); 582#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 583 584 /* Selected IBSS not found in current scan results - try to scan */ 585 if (time_after(jiffies, ifibss->last_scan_completed + 586 IEEE80211_SCAN_INTERVAL)) { 587 printk(KERN_DEBUG "%s: Trigger new scan to find an IBSS to " 588 "join\n", sdata->name); 589 590 ieee80211_request_internal_scan(sdata, ifibss->ssid, 591 ifibss->ssid_len); 592 } else { 593 int interval = IEEE80211_SCAN_INTERVAL; 594 595 if (time_after(jiffies, ifibss->ibss_join_req + 596 IEEE80211_IBSS_JOIN_TIMEOUT)) { 597 if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) { 598 ieee80211_sta_create_ibss(sdata); 599 return; 600 } 601 printk(KERN_DEBUG "%s: IBSS not allowed on" 602 " %d MHz\n", sdata->name, 603 local->hw.conf.channel->center_freq); 604 605 /* No IBSS found - decrease scan interval and continue 606 * scanning. */ 607 interval = IEEE80211_SCAN_INTERVAL_SLOW; 608 } 609 610 mod_timer(&ifibss->timer, 611 round_jiffies(jiffies + interval)); 612 } 613} 614 615static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata, 616 struct ieee80211_mgmt *mgmt, 617 size_t len) 618{ 619 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 620 struct ieee80211_local *local = sdata->local; 621 int tx_last_beacon; 622 struct sk_buff *skb; 623 struct ieee80211_mgmt *resp; 624 u8 *pos, *end; 625 626 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED || 627 len < 24 + 2 || !ifibss->presp) 628 return; 629 630 tx_last_beacon = drv_tx_last_beacon(local); 631 632#ifdef CONFIG_MAC80211_IBSS_DEBUG 633 printk(KERN_DEBUG "%s: RX ProbeReq SA=%pM DA=%pM BSSID=%pM" 634 " (tx_last_beacon=%d)\n", 635 sdata->name, mgmt->sa, mgmt->da, 636 mgmt->bssid, tx_last_beacon); 637#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 638 639 if (!tx_last_beacon) 640 return; 641 642 if (memcmp(mgmt->bssid, ifibss->bssid, ETH_ALEN) != 0 && 643 memcmp(mgmt->bssid, "\xff\xff\xff\xff\xff\xff", ETH_ALEN) != 0) 644 return; 645 646 end = ((u8 *) mgmt) + len; 647 pos = mgmt->u.probe_req.variable; 648 if (pos[0] != WLAN_EID_SSID || 649 pos + 2 + pos[1] > end) { 650#ifdef CONFIG_MAC80211_IBSS_DEBUG 651 printk(KERN_DEBUG "%s: Invalid SSID IE in ProbeReq " 652 "from %pM\n", 653 sdata->name, mgmt->sa); 654#endif 655 return; 656 } 657 if (pos[1] != 0 && 658 (pos[1] != ifibss->ssid_len || 659 memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) { 660 /* Ignore ProbeReq for foreign SSID */ 661 return; 662 } 663 664 /* Reply with ProbeResp */ 665 skb = skb_copy(ifibss->presp, GFP_KERNEL); 666 if (!skb) 667 return; 668 669 resp = (struct ieee80211_mgmt *) skb->data; 670 memcpy(resp->da, mgmt->sa, ETH_ALEN); 671#ifdef CONFIG_MAC80211_IBSS_DEBUG 672 printk(KERN_DEBUG "%s: Sending ProbeResp to %pM\n", 673 sdata->name, resp->da); 674#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 675 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 676 ieee80211_tx_skb(sdata, skb); 677} 678 679static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata, 680 struct ieee80211_mgmt *mgmt, 681 size_t len, 682 struct ieee80211_rx_status *rx_status) 683{ 684 size_t baselen; 685 struct ieee802_11_elems elems; 686 687 if (memcmp(mgmt->da, sdata->vif.addr, ETH_ALEN)) 688 return; /* ignore ProbeResp to foreign address */ 689 690 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt; 691 if (baselen > len) 692 return; 693 694 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen, 695 &elems); 696 697 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false); 698} 699 700static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 701 struct ieee80211_mgmt *mgmt, 702 size_t len, 703 struct ieee80211_rx_status *rx_status) 704{ 705 size_t baselen; 706 struct ieee802_11_elems elems; 707 708 /* Process beacon from the current BSS */ 709 baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt; 710 if (baselen > len) 711 return; 712 713 ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems); 714 715 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true); 716} 717 718static void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata, 719 struct sk_buff *skb) 720{ 721 struct ieee80211_rx_status *rx_status; 722 struct ieee80211_mgmt *mgmt; 723 u16 fc; 724 725 rx_status = IEEE80211_SKB_RXCB(skb); 726 mgmt = (struct ieee80211_mgmt *) skb->data; 727 fc = le16_to_cpu(mgmt->frame_control); 728 729 switch (fc & IEEE80211_FCTL_STYPE) { 730 case IEEE80211_STYPE_PROBE_REQ: 731 ieee80211_rx_mgmt_probe_req(sdata, mgmt, skb->len); 732 break; 733 case IEEE80211_STYPE_PROBE_RESP: 734 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len, 735 rx_status); 736 break; 737 case IEEE80211_STYPE_BEACON: 738 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len, 739 rx_status); 740 break; 741 case IEEE80211_STYPE_AUTH: 742 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len); 743 break; 744 } 745 746 kfree_skb(skb); 747} 748 749static void ieee80211_ibss_work(struct work_struct *work) 750{ 751 struct ieee80211_sub_if_data *sdata = 752 container_of(work, struct ieee80211_sub_if_data, u.ibss.work); 753 struct ieee80211_local *local = sdata->local; 754 struct ieee80211_if_ibss *ifibss; 755 struct sk_buff *skb; 756 757 if (WARN_ON(local->suspended)) 758 return; 759 760 if (!ieee80211_sdata_running(sdata)) 761 return; 762 763 if (local->scanning) 764 return; 765 766 if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_ADHOC)) 767 return; 768 ifibss = &sdata->u.ibss; 769 770 while ((skb = skb_dequeue(&ifibss->skb_queue))) 771 ieee80211_ibss_rx_queued_mgmt(sdata, skb); 772 773 if (!test_and_clear_bit(IEEE80211_IBSS_REQ_RUN, &ifibss->request)) 774 return; 775 776 switch (ifibss->state) { 777 case IEEE80211_IBSS_MLME_SEARCH: 778 ieee80211_sta_find_ibss(sdata); 779 break; 780 case IEEE80211_IBSS_MLME_JOINED: 781 ieee80211_sta_merge_ibss(sdata); 782 break; 783 default: 784 WARN_ON(1); 785 break; 786 } 787} 788 789static void ieee80211_ibss_timer(unsigned long data) 790{ 791 struct ieee80211_sub_if_data *sdata = 792 (struct ieee80211_sub_if_data *) data; 793 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 794 struct ieee80211_local *local = sdata->local; 795 796 if (local->quiescing) { 797 ifibss->timer_running = true; 798 return; 799 } 800 801 set_bit(IEEE80211_IBSS_REQ_RUN, &ifibss->request); 802 ieee80211_queue_work(&local->hw, &ifibss->work); 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 cancel_work_sync(&ifibss->work); 811 if (del_timer_sync(&ifibss->timer)) 812 ifibss->timer_running = true; 813} 814 815void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata) 816{ 817 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 818 819 if (ifibss->timer_running) { 820 add_timer(&ifibss->timer); 821 ifibss->timer_running = false; 822 } 823} 824#endif 825 826void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata) 827{ 828 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 829 830 INIT_WORK(&ifibss->work, ieee80211_ibss_work); 831 setup_timer(&ifibss->timer, ieee80211_ibss_timer, 832 (unsigned long) sdata); 833 skb_queue_head_init(&ifibss->skb_queue); 834} 835 836/* scan finished notification */ 837void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local) 838{ 839 struct ieee80211_sub_if_data *sdata; 840 841 mutex_lock(&local->iflist_mtx); 842 list_for_each_entry(sdata, &local->interfaces, list) { 843 if (!ieee80211_sdata_running(sdata)) 844 continue; 845 if (sdata->vif.type != NL80211_IFTYPE_ADHOC) 846 continue; 847 if (!sdata->u.ibss.ssid_len) 848 continue; 849 sdata->u.ibss.last_scan_completed = jiffies; 850 mod_timer(&sdata->u.ibss.timer, 0); 851 } 852 mutex_unlock(&local->iflist_mtx); 853} 854 855ieee80211_rx_result 856ieee80211_ibss_rx_mgmt(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb) 857{ 858 struct ieee80211_local *local = sdata->local; 859 struct ieee80211_mgmt *mgmt; 860 u16 fc; 861 862 if (skb->len < 24) 863 return RX_DROP_MONITOR; 864 865 mgmt = (struct ieee80211_mgmt *) skb->data; 866 fc = le16_to_cpu(mgmt->frame_control); 867 868 switch (fc & IEEE80211_FCTL_STYPE) { 869 case IEEE80211_STYPE_PROBE_RESP: 870 case IEEE80211_STYPE_BEACON: 871 case IEEE80211_STYPE_PROBE_REQ: 872 case IEEE80211_STYPE_AUTH: 873 skb_queue_tail(&sdata->u.ibss.skb_queue, skb); 874 ieee80211_queue_work(&local->hw, &sdata->u.ibss.work); 875 return RX_QUEUED; 876 } 877 878 return RX_DROP_MONITOR; 879} 880 881int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata, 882 struct cfg80211_ibss_params *params) 883{ 884 struct sk_buff *skb; 885 886 if (params->bssid) { 887 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN); 888 sdata->u.ibss.fixed_bssid = true; 889 } else 890 sdata->u.ibss.fixed_bssid = false; 891 892 sdata->u.ibss.privacy = params->privacy; 893 894 sdata->vif.bss_conf.beacon_int = params->beacon_interval; 895 896 sdata->u.ibss.channel = params->channel; 897 sdata->u.ibss.fixed_channel = params->channel_fixed; 898 899 if (params->ie) { 900 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len, 901 GFP_KERNEL); 902 if (sdata->u.ibss.ie) 903 sdata->u.ibss.ie_len = params->ie_len; 904 } 905 906 skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom + 907 36 /* bitrates */ + 908 34 /* SSID */ + 909 3 /* DS params */ + 910 4 /* IBSS params */ + 911 params->ie_len); 912 if (!skb) 913 return -ENOMEM; 914 915 sdata->u.ibss.skb = skb; 916 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; 917 sdata->u.ibss.ibss_join_req = jiffies; 918 919 memcpy(sdata->u.ibss.ssid, params->ssid, IEEE80211_MAX_SSID_LEN); 920 921 /* 922 * The ssid_len setting below is used to see whether 923 * we are active, and we need all other settings 924 * before that may get visible. 925 */ 926 mb(); 927 928 sdata->u.ibss.ssid_len = params->ssid_len; 929 930 ieee80211_recalc_idle(sdata->local); 931 932 set_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request); 933 ieee80211_queue_work(&sdata->local->hw, &sdata->u.ibss.work); 934 935 return 0; 936} 937 938int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata) 939{ 940 struct sk_buff *skb; 941 942 del_timer_sync(&sdata->u.ibss.timer); 943 clear_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request); 944 cancel_work_sync(&sdata->u.ibss.work); 945 clear_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request); 946 947 sta_info_flush(sdata->local, sdata); 948 949 /* remove beacon */ 950 kfree(sdata->u.ibss.ie); 951 skb = sdata->u.ibss.presp; 952 rcu_assign_pointer(sdata->u.ibss.presp, NULL); 953 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED); 954 synchronize_rcu(); 955 kfree_skb(skb); 956 957 skb_queue_purge(&sdata->u.ibss.skb_queue); 958 memset(sdata->u.ibss.bssid, 0, ETH_ALEN); 959 sdata->u.ibss.ssid_len = 0; 960 961 ieee80211_recalc_idle(sdata->local); 962 963 return 0; 964} 965