ibss.c revision 51f98f1313d2fc4b1d3a3e1f4db7cf4925b29df6
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 u32 bss_change; 77 u8 supp_rates[IEEE80211_MAX_SUPP_RATES]; 78 79 /* Reset own TSF to allow time synchronization work. */ 80 drv_reset_tsf(local); 81 82 skb = ifibss->skb; 83 rcu_assign_pointer(ifibss->presp, NULL); 84 synchronize_rcu(); 85 skb->data = skb->head; 86 skb->len = 0; 87 skb_reset_tail_pointer(skb); 88 skb_reserve(skb, sdata->local->hw.extra_tx_headroom); 89 90 if (memcmp(ifibss->bssid, bssid, ETH_ALEN)) 91 sta_info_flush(sdata->local, sdata); 92 93 memcpy(ifibss->bssid, bssid, ETH_ALEN); 94 95 sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0; 96 97 local->oper_channel = chan; 98 local->oper_channel_type = NL80211_CHAN_NO_HT; 99 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); 100 101 sband = local->hw.wiphy->bands[chan->band]; 102 103 /* build supported rates array */ 104 pos = supp_rates; 105 for (i = 0; i < sband->n_bitrates; i++) { 106 int rate = sband->bitrates[i].bitrate; 107 u8 basic = 0; 108 if (basic_rates & BIT(i)) 109 basic = 0x80; 110 *pos++ = basic | (u8) (rate / 5); 111 } 112 113 /* Build IBSS probe response */ 114 mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon)); 115 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon)); 116 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 117 IEEE80211_STYPE_PROBE_RESP); 118 memset(mgmt->da, 0xff, ETH_ALEN); 119 memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN); 120 memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN); 121 mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int); 122 mgmt->u.beacon.timestamp = cpu_to_le64(tsf); 123 mgmt->u.beacon.capab_info = cpu_to_le16(capability); 124 125 pos = skb_put(skb, 2 + ifibss->ssid_len); 126 *pos++ = WLAN_EID_SSID; 127 *pos++ = ifibss->ssid_len; 128 memcpy(pos, ifibss->ssid, ifibss->ssid_len); 129 130 rates = sband->n_bitrates; 131 if (rates > 8) 132 rates = 8; 133 pos = skb_put(skb, 2 + rates); 134 *pos++ = WLAN_EID_SUPP_RATES; 135 *pos++ = rates; 136 memcpy(pos, supp_rates, rates); 137 138 if (sband->band == IEEE80211_BAND_2GHZ) { 139 pos = skb_put(skb, 2 + 1); 140 *pos++ = WLAN_EID_DS_PARAMS; 141 *pos++ = 1; 142 *pos++ = ieee80211_frequency_to_channel(chan->center_freq); 143 } 144 145 pos = skb_put(skb, 2 + 2); 146 *pos++ = WLAN_EID_IBSS_PARAMS; 147 *pos++ = 2; 148 /* FIX: set ATIM window based on scan results */ 149 *pos++ = 0; 150 *pos++ = 0; 151 152 if (sband->n_bitrates > 8) { 153 rates = sband->n_bitrates - 8; 154 pos = skb_put(skb, 2 + rates); 155 *pos++ = WLAN_EID_EXT_SUPP_RATES; 156 *pos++ = rates; 157 memcpy(pos, &supp_rates[8], rates); 158 } 159 160 if (ifibss->ie_len) 161 memcpy(skb_put(skb, ifibss->ie_len), 162 ifibss->ie, ifibss->ie_len); 163 164 rcu_assign_pointer(ifibss->presp, skb); 165 166 sdata->vif.bss_conf.beacon_int = beacon_int; 167 bss_change = BSS_CHANGED_BEACON_INT; 168 bss_change |= ieee80211_reset_erp_info(sdata); 169 bss_change |= BSS_CHANGED_BSSID; 170 bss_change |= BSS_CHANGED_BEACON; 171 bss_change |= BSS_CHANGED_BEACON_ENABLED; 172 ieee80211_bss_info_change_notify(sdata, bss_change); 173 174 ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates); 175 176 ifibss->state = IEEE80211_IBSS_MLME_JOINED; 177 mod_timer(&ifibss->timer, 178 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 179 180 cfg80211_inform_bss_frame(local->hw.wiphy, local->hw.conf.channel, 181 mgmt, skb->len, 0, GFP_KERNEL); 182 cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL); 183} 184 185static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 186 struct ieee80211_bss *bss) 187{ 188 struct ieee80211_supported_band *sband; 189 u32 basic_rates; 190 int i, j; 191 u16 beacon_int = bss->cbss.beacon_interval; 192 193 if (beacon_int < 10) 194 beacon_int = 10; 195 196 sband = sdata->local->hw.wiphy->bands[bss->cbss.channel->band]; 197 198 basic_rates = 0; 199 200 for (i = 0; i < bss->supp_rates_len; i++) { 201 int rate = (bss->supp_rates[i] & 0x7f) * 5; 202 bool is_basic = !!(bss->supp_rates[i] & 0x80); 203 204 for (j = 0; j < sband->n_bitrates; j++) { 205 if (sband->bitrates[j].bitrate == rate) { 206 if (is_basic) 207 basic_rates |= BIT(j); 208 break; 209 } 210 } 211 } 212 213 __ieee80211_sta_join_ibss(sdata, bss->cbss.bssid, 214 beacon_int, 215 bss->cbss.channel, 216 basic_rates, 217 bss->cbss.capability, 218 bss->cbss.tsf); 219} 220 221static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, 222 struct ieee80211_mgmt *mgmt, 223 size_t len, 224 struct ieee80211_rx_status *rx_status, 225 struct ieee802_11_elems *elems, 226 bool beacon) 227{ 228 struct ieee80211_local *local = sdata->local; 229 int freq; 230 struct ieee80211_bss *bss; 231 struct sta_info *sta; 232 struct ieee80211_channel *channel; 233 u64 beacon_timestamp, rx_timestamp; 234 u32 supp_rates = 0; 235 enum ieee80211_band band = rx_status->band; 236 237 if (elems->ds_params && elems->ds_params_len == 1) 238 freq = ieee80211_channel_to_frequency(elems->ds_params[0]); 239 else 240 freq = rx_status->freq; 241 242 channel = ieee80211_get_channel(local->hw.wiphy, freq); 243 244 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 245 return; 246 247 if (sdata->vif.type == NL80211_IFTYPE_ADHOC && elems->supp_rates && 248 memcmp(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) { 249 supp_rates = ieee80211_sta_get_rates(local, elems, band); 250 251 rcu_read_lock(); 252 253 sta = sta_info_get(local, mgmt->sa); 254 if (sta) { 255 u32 prev_rates; 256 257 prev_rates = sta->sta.supp_rates[band]; 258 /* make sure mandatory rates are always added */ 259 sta->sta.supp_rates[band] = supp_rates | 260 ieee80211_mandatory_rates(local, band); 261 262#ifdef CONFIG_MAC80211_IBSS_DEBUG 263 if (sta->sta.supp_rates[band] != prev_rates) 264 printk(KERN_DEBUG "%s: updated supp_rates set " 265 "for %pM based on beacon info (0x%llx | " 266 "0x%llx -> 0x%llx)\n", 267 sdata->dev->name, 268 sta->sta.addr, 269 (unsigned long long) prev_rates, 270 (unsigned long long) supp_rates, 271 (unsigned long long) sta->sta.supp_rates[band]); 272#endif 273 } else 274 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, supp_rates); 275 276 rcu_read_unlock(); 277 } 278 279 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems, 280 channel, beacon); 281 if (!bss) 282 return; 283 284 /* was just updated in ieee80211_bss_info_update */ 285 beacon_timestamp = bss->cbss.tsf; 286 287 /* check if we need to merge IBSS */ 288 289 /* merge only on beacons (???) */ 290 if (!beacon) 291 goto put_bss; 292 293 /* we use a fixed BSSID */ 294 if (sdata->u.ibss.bssid) 295 goto put_bss; 296 297 /* not an IBSS */ 298 if (!(bss->cbss.capability & WLAN_CAPABILITY_IBSS)) 299 goto put_bss; 300 301 /* different channel */ 302 if (bss->cbss.channel != local->oper_channel) 303 goto put_bss; 304 305 /* different SSID */ 306 if (elems->ssid_len != sdata->u.ibss.ssid_len || 307 memcmp(elems->ssid, sdata->u.ibss.ssid, 308 sdata->u.ibss.ssid_len)) 309 goto put_bss; 310 311 /* same BSSID */ 312 if (memcmp(bss->cbss.bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) 313 goto put_bss; 314 315 if (rx_status->flag & RX_FLAG_TSFT) { 316 /* 317 * For correct IBSS merging we need mactime; since mactime is 318 * defined as the time the first data symbol of the frame hits 319 * the PHY, and the timestamp of the beacon is defined as "the 320 * time that the data symbol containing the first bit of the 321 * timestamp is transmitted to the PHY plus the transmitting 322 * STA's delays through its local PHY from the MAC-PHY 323 * interface to its interface with the WM" (802.11 11.1.2) 324 * - equals the time this bit arrives at the receiver - we have 325 * to take into account the offset between the two. 326 * 327 * E.g. at 1 MBit that means mactime is 192 usec earlier 328 * (=24 bytes * 8 usecs/byte) than the beacon timestamp. 329 */ 330 int rate; 331 332 if (rx_status->flag & RX_FLAG_HT) 333 rate = 65; /* TODO: HT rates */ 334 else 335 rate = local->hw.wiphy->bands[band]-> 336 bitrates[rx_status->rate_idx].bitrate; 337 338 rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate); 339 } else { 340 /* 341 * second best option: get current TSF 342 * (will return -1 if not supported) 343 */ 344 rx_timestamp = drv_get_tsf(local); 345 } 346 347#ifdef CONFIG_MAC80211_IBSS_DEBUG 348 printk(KERN_DEBUG "RX beacon SA=%pM BSSID=" 349 "%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n", 350 mgmt->sa, mgmt->bssid, 351 (unsigned long long)rx_timestamp, 352 (unsigned long long)beacon_timestamp, 353 (unsigned long long)(rx_timestamp - beacon_timestamp), 354 jiffies); 355#endif 356 357 /* give slow hardware some time to do the TSF sync */ 358 if (rx_timestamp < IEEE80211_IBSS_MERGE_DELAY) 359 goto put_bss; 360 361 if (beacon_timestamp > rx_timestamp) { 362#ifdef CONFIG_MAC80211_IBSS_DEBUG 363 printk(KERN_DEBUG "%s: beacon TSF higher than " 364 "local TSF - IBSS merge with BSSID %pM\n", 365 sdata->dev->name, mgmt->bssid); 366#endif 367 ieee80211_sta_join_ibss(sdata, bss); 368 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, supp_rates); 369 } 370 371 put_bss: 372 ieee80211_rx_bss_put(local, bss); 373} 374 375/* 376 * Add a new IBSS station, will also be called by the RX code when, 377 * in IBSS mode, receiving a frame from a yet-unknown station, hence 378 * must be callable in atomic context. 379 */ 380struct sta_info *ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, 381 u8 *bssid,u8 *addr, u32 supp_rates) 382{ 383 struct ieee80211_local *local = sdata->local; 384 struct sta_info *sta; 385 int band = local->hw.conf.channel->band; 386 387 /* 388 * XXX: Consider removing the least recently used entry and 389 * allow new one to be added. 390 */ 391 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 392 if (net_ratelimit()) 393 printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n", 394 sdata->dev->name, addr); 395 return NULL; 396 } 397 398 if (compare_ether_addr(bssid, sdata->u.ibss.bssid)) 399 return NULL; 400 401#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 402 printk(KERN_DEBUG "%s: Adding new IBSS station %pM (dev=%s)\n", 403 wiphy_name(local->hw.wiphy), addr, sdata->dev->name); 404#endif 405 406 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC); 407 if (!sta) 408 return NULL; 409 410 set_sta_flags(sta, WLAN_STA_AUTHORIZED); 411 412 /* make sure mandatory rates are always added */ 413 sta->sta.supp_rates[band] = supp_rates | 414 ieee80211_mandatory_rates(local, band); 415 416 rate_control_rate_init(sta); 417 418 if (sta_info_insert(sta)) 419 return NULL; 420 421 return sta; 422} 423 424static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata) 425{ 426 struct ieee80211_local *local = sdata->local; 427 int active = 0; 428 struct sta_info *sta; 429 430 rcu_read_lock(); 431 432 list_for_each_entry_rcu(sta, &local->sta_list, list) { 433 if (sta->sdata == sdata && 434 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL, 435 jiffies)) { 436 active++; 437 break; 438 } 439 } 440 441 rcu_read_unlock(); 442 443 return active; 444} 445 446 447static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata) 448{ 449 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 450 451 mod_timer(&ifibss->timer, 452 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 453 454 ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT); 455 456 if (ieee80211_sta_active_ibss(sdata)) 457 return; 458 459 if (ifibss->fixed_channel) 460 return; 461 462 printk(KERN_DEBUG "%s: No active IBSS STAs - trying to scan for other " 463 "IBSS networks with same SSID (merge)\n", sdata->dev->name); 464 465 ieee80211_request_internal_scan(sdata, ifibss->ssid, ifibss->ssid_len); 466} 467 468static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata) 469{ 470 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 471 struct ieee80211_local *local = sdata->local; 472 struct ieee80211_supported_band *sband; 473 u8 bssid[ETH_ALEN]; 474 u16 capability; 475 int i; 476 477 if (ifibss->fixed_bssid) { 478 memcpy(bssid, ifibss->bssid, ETH_ALEN); 479 } else { 480 /* Generate random, not broadcast, locally administered BSSID. Mix in 481 * own MAC address to make sure that devices that do not have proper 482 * random number generator get different BSSID. */ 483 get_random_bytes(bssid, ETH_ALEN); 484 for (i = 0; i < ETH_ALEN; i++) 485 bssid[i] ^= sdata->dev->dev_addr[i]; 486 bssid[0] &= ~0x01; 487 bssid[0] |= 0x02; 488 } 489 490 printk(KERN_DEBUG "%s: Creating new IBSS network, BSSID %pM\n", 491 sdata->dev->name, bssid); 492 493 sband = local->hw.wiphy->bands[ifibss->channel->band]; 494 495 capability = WLAN_CAPABILITY_IBSS; 496 497 if (ifibss->privacy) 498 capability |= WLAN_CAPABILITY_PRIVACY; 499 else 500 sdata->drop_unencrypted = 0; 501 502 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int, 503 ifibss->channel, 3, /* first two are basic */ 504 capability, 0); 505} 506 507static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata) 508{ 509 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 510 struct ieee80211_local *local = sdata->local; 511 struct ieee80211_bss *bss; 512 struct ieee80211_channel *chan = NULL; 513 const u8 *bssid = NULL; 514 int active_ibss; 515 u16 capability; 516 517 active_ibss = ieee80211_sta_active_ibss(sdata); 518#ifdef CONFIG_MAC80211_IBSS_DEBUG 519 printk(KERN_DEBUG "%s: sta_find_ibss (active_ibss=%d)\n", 520 sdata->dev->name, active_ibss); 521#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 522 523 if (active_ibss) 524 return; 525 526 capability = WLAN_CAPABILITY_IBSS; 527 if (ifibss->privacy) 528 capability |= WLAN_CAPABILITY_PRIVACY; 529 if (ifibss->fixed_bssid) 530 bssid = ifibss->bssid; 531 if (ifibss->fixed_channel) 532 chan = ifibss->channel; 533 if (!is_zero_ether_addr(ifibss->bssid)) 534 bssid = ifibss->bssid; 535 bss = (void *)cfg80211_get_bss(local->hw.wiphy, chan, bssid, 536 ifibss->ssid, ifibss->ssid_len, 537 WLAN_CAPABILITY_IBSS | 538 WLAN_CAPABILITY_PRIVACY, 539 capability); 540 541#ifdef CONFIG_MAC80211_IBSS_DEBUG 542 if (bss) 543 printk(KERN_DEBUG " sta_find_ibss: selected %pM current " 544 "%pM\n", bss->cbss.bssid, ifibss->bssid); 545#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 546 547 if (bss && !memcmp(ifibss->bssid, bss->cbss.bssid, ETH_ALEN)) { 548 printk(KERN_DEBUG "%s: Selected IBSS BSSID %pM" 549 " based on configured SSID\n", 550 sdata->dev->name, bss->cbss.bssid); 551 552 ieee80211_sta_join_ibss(sdata, bss); 553 ieee80211_rx_bss_put(local, bss); 554 return; 555 } else if (bss) 556 ieee80211_rx_bss_put(local, bss); 557 558#ifdef CONFIG_MAC80211_IBSS_DEBUG 559 printk(KERN_DEBUG " did not try to join ibss\n"); 560#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 561 562 /* Selected IBSS not found in current scan results - try to scan */ 563 if (ifibss->state == IEEE80211_IBSS_MLME_JOINED && 564 !ieee80211_sta_active_ibss(sdata)) { 565 mod_timer(&ifibss->timer, 566 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 567 } else if (time_after(jiffies, ifibss->last_scan_completed + 568 IEEE80211_SCAN_INTERVAL)) { 569 printk(KERN_DEBUG "%s: Trigger new scan to find an IBSS to " 570 "join\n", sdata->dev->name); 571 572 ieee80211_request_internal_scan(sdata, ifibss->ssid, 573 ifibss->ssid_len); 574 } else if (ifibss->state != IEEE80211_IBSS_MLME_JOINED) { 575 int interval = IEEE80211_SCAN_INTERVAL; 576 577 if (time_after(jiffies, ifibss->ibss_join_req + 578 IEEE80211_IBSS_JOIN_TIMEOUT)) { 579 if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) { 580 ieee80211_sta_create_ibss(sdata); 581 return; 582 } 583 printk(KERN_DEBUG "%s: IBSS not allowed on" 584 " %d MHz\n", sdata->dev->name, 585 local->hw.conf.channel->center_freq); 586 587 /* No IBSS found - decrease scan interval and continue 588 * scanning. */ 589 interval = IEEE80211_SCAN_INTERVAL_SLOW; 590 } 591 592 ifibss->state = IEEE80211_IBSS_MLME_SEARCH; 593 mod_timer(&ifibss->timer, 594 round_jiffies(jiffies + interval)); 595 } 596} 597 598static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata, 599 struct ieee80211_mgmt *mgmt, 600 size_t len) 601{ 602 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 603 struct ieee80211_local *local = sdata->local; 604 int tx_last_beacon; 605 struct sk_buff *skb; 606 struct ieee80211_mgmt *resp; 607 u8 *pos, *end; 608 609 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED || 610 len < 24 + 2 || !ifibss->presp) 611 return; 612 613 tx_last_beacon = drv_tx_last_beacon(local); 614 615#ifdef CONFIG_MAC80211_IBSS_DEBUG 616 printk(KERN_DEBUG "%s: RX ProbeReq SA=%pM DA=%pM BSSID=%pM" 617 " (tx_last_beacon=%d)\n", 618 sdata->dev->name, mgmt->sa, mgmt->da, 619 mgmt->bssid, tx_last_beacon); 620#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 621 622 if (!tx_last_beacon) 623 return; 624 625 if (memcmp(mgmt->bssid, ifibss->bssid, ETH_ALEN) != 0 && 626 memcmp(mgmt->bssid, "\xff\xff\xff\xff\xff\xff", ETH_ALEN) != 0) 627 return; 628 629 end = ((u8 *) mgmt) + len; 630 pos = mgmt->u.probe_req.variable; 631 if (pos[0] != WLAN_EID_SSID || 632 pos + 2 + pos[1] > end) { 633#ifdef CONFIG_MAC80211_IBSS_DEBUG 634 printk(KERN_DEBUG "%s: Invalid SSID IE in ProbeReq " 635 "from %pM\n", 636 sdata->dev->name, mgmt->sa); 637#endif 638 return; 639 } 640 if (pos[1] != 0 && 641 (pos[1] != ifibss->ssid_len || 642 !memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) { 643 /* Ignore ProbeReq for foreign SSID */ 644 return; 645 } 646 647 /* Reply with ProbeResp */ 648 skb = skb_copy(ifibss->presp, GFP_KERNEL); 649 if (!skb) 650 return; 651 652 resp = (struct ieee80211_mgmt *) skb->data; 653 memcpy(resp->da, mgmt->sa, ETH_ALEN); 654#ifdef CONFIG_MAC80211_IBSS_DEBUG 655 printk(KERN_DEBUG "%s: Sending ProbeResp to %pM\n", 656 sdata->dev->name, resp->da); 657#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 658 ieee80211_tx_skb(sdata, skb, 0); 659} 660 661static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata, 662 struct ieee80211_mgmt *mgmt, 663 size_t len, 664 struct ieee80211_rx_status *rx_status) 665{ 666 size_t baselen; 667 struct ieee802_11_elems elems; 668 669 if (memcmp(mgmt->da, sdata->dev->dev_addr, ETH_ALEN)) 670 return; /* ignore ProbeResp to foreign address */ 671 672 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt; 673 if (baselen > len) 674 return; 675 676 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen, 677 &elems); 678 679 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false); 680} 681 682static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 683 struct ieee80211_mgmt *mgmt, 684 size_t len, 685 struct ieee80211_rx_status *rx_status) 686{ 687 size_t baselen; 688 struct ieee802_11_elems elems; 689 690 /* Process beacon from the current BSS */ 691 baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt; 692 if (baselen > len) 693 return; 694 695 ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems); 696 697 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true); 698} 699 700static void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata, 701 struct sk_buff *skb) 702{ 703 struct ieee80211_rx_status *rx_status; 704 struct ieee80211_mgmt *mgmt; 705 u16 fc; 706 707 rx_status = IEEE80211_SKB_RXCB(skb); 708 mgmt = (struct ieee80211_mgmt *) skb->data; 709 fc = le16_to_cpu(mgmt->frame_control); 710 711 switch (fc & IEEE80211_FCTL_STYPE) { 712 case IEEE80211_STYPE_PROBE_REQ: 713 ieee80211_rx_mgmt_probe_req(sdata, mgmt, skb->len); 714 break; 715 case IEEE80211_STYPE_PROBE_RESP: 716 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len, 717 rx_status); 718 break; 719 case IEEE80211_STYPE_BEACON: 720 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len, 721 rx_status); 722 break; 723 case IEEE80211_STYPE_AUTH: 724 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len); 725 break; 726 } 727 728 kfree_skb(skb); 729} 730 731static void ieee80211_ibss_work(struct work_struct *work) 732{ 733 struct ieee80211_sub_if_data *sdata = 734 container_of(work, struct ieee80211_sub_if_data, u.ibss.work); 735 struct ieee80211_local *local = sdata->local; 736 struct ieee80211_if_ibss *ifibss; 737 struct sk_buff *skb; 738 739 if (WARN_ON(local->suspended)) 740 return; 741 742 if (!netif_running(sdata->dev)) 743 return; 744 745 if (local->scanning) 746 return; 747 748 if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_ADHOC)) 749 return; 750 ifibss = &sdata->u.ibss; 751 752 while ((skb = skb_dequeue(&ifibss->skb_queue))) 753 ieee80211_ibss_rx_queued_mgmt(sdata, skb); 754 755 if (!test_and_clear_bit(IEEE80211_IBSS_REQ_RUN, &ifibss->request)) 756 return; 757 758 switch (ifibss->state) { 759 case IEEE80211_IBSS_MLME_SEARCH: 760 ieee80211_sta_find_ibss(sdata); 761 break; 762 case IEEE80211_IBSS_MLME_JOINED: 763 ieee80211_sta_merge_ibss(sdata); 764 break; 765 default: 766 WARN_ON(1); 767 break; 768 } 769} 770 771static void ieee80211_ibss_timer(unsigned long data) 772{ 773 struct ieee80211_sub_if_data *sdata = 774 (struct ieee80211_sub_if_data *) data; 775 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 776 struct ieee80211_local *local = sdata->local; 777 778 if (local->quiescing) { 779 ifibss->timer_running = true; 780 return; 781 } 782 783 set_bit(IEEE80211_IBSS_REQ_RUN, &ifibss->request); 784 ieee80211_queue_work(&local->hw, &ifibss->work); 785} 786 787#ifdef CONFIG_PM 788void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata) 789{ 790 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 791 792 cancel_work_sync(&ifibss->work); 793 if (del_timer_sync(&ifibss->timer)) 794 ifibss->timer_running = true; 795} 796 797void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata) 798{ 799 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 800 801 if (ifibss->timer_running) { 802 add_timer(&ifibss->timer); 803 ifibss->timer_running = false; 804 } 805} 806#endif 807 808void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata) 809{ 810 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 811 812 INIT_WORK(&ifibss->work, ieee80211_ibss_work); 813 setup_timer(&ifibss->timer, ieee80211_ibss_timer, 814 (unsigned long) sdata); 815 skb_queue_head_init(&ifibss->skb_queue); 816} 817 818/* scan finished notification */ 819void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local) 820{ 821 struct ieee80211_sub_if_data *sdata; 822 823 mutex_lock(&local->iflist_mtx); 824 list_for_each_entry(sdata, &local->interfaces, list) { 825 if (!netif_running(sdata->dev)) 826 continue; 827 if (sdata->vif.type != NL80211_IFTYPE_ADHOC) 828 continue; 829 if (!sdata->u.ibss.ssid_len) 830 continue; 831 sdata->u.ibss.last_scan_completed = jiffies; 832 mod_timer(&sdata->u.ibss.timer, 0); 833 } 834 mutex_unlock(&local->iflist_mtx); 835} 836 837ieee80211_rx_result 838ieee80211_ibss_rx_mgmt(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb) 839{ 840 struct ieee80211_local *local = sdata->local; 841 struct ieee80211_mgmt *mgmt; 842 u16 fc; 843 844 if (skb->len < 24) 845 return RX_DROP_MONITOR; 846 847 mgmt = (struct ieee80211_mgmt *) skb->data; 848 fc = le16_to_cpu(mgmt->frame_control); 849 850 switch (fc & IEEE80211_FCTL_STYPE) { 851 case IEEE80211_STYPE_PROBE_RESP: 852 case IEEE80211_STYPE_BEACON: 853 case IEEE80211_STYPE_PROBE_REQ: 854 case IEEE80211_STYPE_AUTH: 855 skb_queue_tail(&sdata->u.ibss.skb_queue, skb); 856 ieee80211_queue_work(&local->hw, &sdata->u.ibss.work); 857 return RX_QUEUED; 858 } 859 860 return RX_DROP_MONITOR; 861} 862 863int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata, 864 struct cfg80211_ibss_params *params) 865{ 866 struct sk_buff *skb; 867 868 if (params->bssid) { 869 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN); 870 sdata->u.ibss.fixed_bssid = true; 871 } else 872 sdata->u.ibss.fixed_bssid = false; 873 874 sdata->u.ibss.privacy = params->privacy; 875 876 sdata->vif.bss_conf.beacon_int = params->beacon_interval; 877 878 sdata->u.ibss.channel = params->channel; 879 sdata->u.ibss.fixed_channel = params->channel_fixed; 880 881 if (params->ie) { 882 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len, 883 GFP_KERNEL); 884 if (sdata->u.ibss.ie) 885 sdata->u.ibss.ie_len = params->ie_len; 886 } 887 888 skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom + 889 36 /* bitrates */ + 890 34 /* SSID */ + 891 3 /* DS params */ + 892 4 /* IBSS params */ + 893 params->ie_len); 894 if (!skb) 895 return -ENOMEM; 896 897 sdata->u.ibss.skb = skb; 898 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; 899 sdata->u.ibss.ibss_join_req = jiffies; 900 901 memcpy(sdata->u.ibss.ssid, params->ssid, IEEE80211_MAX_SSID_LEN); 902 903 /* 904 * The ssid_len setting below is used to see whether 905 * we are active, and we need all other settings 906 * before that may get visible. 907 */ 908 mb(); 909 910 sdata->u.ibss.ssid_len = params->ssid_len; 911 912 ieee80211_recalc_idle(sdata->local); 913 914 set_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request); 915 ieee80211_queue_work(&sdata->local->hw, &sdata->u.ibss.work); 916 917 return 0; 918} 919 920int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata) 921{ 922 struct sk_buff *skb; 923 924 del_timer_sync(&sdata->u.ibss.timer); 925 clear_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request); 926 cancel_work_sync(&sdata->u.ibss.work); 927 clear_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request); 928 929 sta_info_flush(sdata->local, sdata); 930 931 /* remove beacon */ 932 kfree(sdata->u.ibss.ie); 933 skb = sdata->u.ibss.presp; 934 rcu_assign_pointer(sdata->u.ibss.presp, NULL); 935 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED); 936 synchronize_rcu(); 937 kfree_skb(skb); 938 939 skb_queue_purge(&sdata->u.ibss.skb_queue); 940 memset(sdata->u.ibss.bssid, 0, ETH_ALEN); 941 sdata->u.ibss.ssid_len = 0; 942 943 ieee80211_recalc_idle(sdata->local); 944 945 return 0; 946} 947