ibss.c revision 2e10d330f8d5f039fa1e00baf59435ab0f11c722
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->dev->dev_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 ieee80211_supported_band *sband; 191 u32 basic_rates; 192 int i, j; 193 u16 beacon_int = bss->cbss.beacon_interval; 194 195 if (beacon_int < 10) 196 beacon_int = 10; 197 198 sband = sdata->local->hw.wiphy->bands[bss->cbss.channel->band]; 199 200 basic_rates = 0; 201 202 for (i = 0; i < bss->supp_rates_len; i++) { 203 int rate = (bss->supp_rates[i] & 0x7f) * 5; 204 bool is_basic = !!(bss->supp_rates[i] & 0x80); 205 206 for (j = 0; j < sband->n_bitrates; j++) { 207 if (sband->bitrates[j].bitrate == rate) { 208 if (is_basic) 209 basic_rates |= BIT(j); 210 break; 211 } 212 } 213 } 214 215 __ieee80211_sta_join_ibss(sdata, bss->cbss.bssid, 216 beacon_int, 217 bss->cbss.channel, 218 basic_rates, 219 bss->cbss.capability, 220 bss->cbss.tsf); 221} 222 223static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, 224 struct ieee80211_mgmt *mgmt, 225 size_t len, 226 struct ieee80211_rx_status *rx_status, 227 struct ieee802_11_elems *elems, 228 bool beacon) 229{ 230 struct ieee80211_local *local = sdata->local; 231 int freq; 232 struct ieee80211_bss *bss; 233 struct sta_info *sta; 234 struct ieee80211_channel *channel; 235 u64 beacon_timestamp, rx_timestamp; 236 u32 supp_rates = 0; 237 enum ieee80211_band band = rx_status->band; 238 239 if (elems->ds_params && elems->ds_params_len == 1) 240 freq = ieee80211_channel_to_frequency(elems->ds_params[0]); 241 else 242 freq = rx_status->freq; 243 244 channel = ieee80211_get_channel(local->hw.wiphy, freq); 245 246 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 247 return; 248 249 if (sdata->vif.type == NL80211_IFTYPE_ADHOC && elems->supp_rates && 250 memcmp(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) { 251 supp_rates = ieee80211_sta_get_rates(local, elems, band); 252 253 rcu_read_lock(); 254 255 sta = sta_info_get(local, mgmt->sa); 256 if (sta) { 257 u32 prev_rates; 258 259 prev_rates = sta->sta.supp_rates[band]; 260 /* make sure mandatory rates are always added */ 261 sta->sta.supp_rates[band] = supp_rates | 262 ieee80211_mandatory_rates(local, band); 263 264#ifdef CONFIG_MAC80211_IBSS_DEBUG 265 if (sta->sta.supp_rates[band] != prev_rates) 266 printk(KERN_DEBUG "%s: updated supp_rates set " 267 "for %pM based on beacon info (0x%llx | " 268 "0x%llx -> 0x%llx)\n", 269 sdata->dev->name, 270 sta->sta.addr, 271 (unsigned long long) prev_rates, 272 (unsigned long long) supp_rates, 273 (unsigned long long) sta->sta.supp_rates[band]); 274#endif 275 } else 276 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, supp_rates); 277 278 rcu_read_unlock(); 279 } 280 281 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems, 282 channel, beacon); 283 if (!bss) 284 return; 285 286 /* was just updated in ieee80211_bss_info_update */ 287 beacon_timestamp = bss->cbss.tsf; 288 289 /* check if we need to merge IBSS */ 290 291 /* merge only on beacons (???) */ 292 if (!beacon) 293 goto put_bss; 294 295 /* we use a fixed BSSID */ 296 if (sdata->u.ibss.bssid) 297 goto put_bss; 298 299 /* not an IBSS */ 300 if (!(bss->cbss.capability & WLAN_CAPABILITY_IBSS)) 301 goto put_bss; 302 303 /* different channel */ 304 if (bss->cbss.channel != local->oper_channel) 305 goto put_bss; 306 307 /* different SSID */ 308 if (elems->ssid_len != sdata->u.ibss.ssid_len || 309 memcmp(elems->ssid, sdata->u.ibss.ssid, 310 sdata->u.ibss.ssid_len)) 311 goto put_bss; 312 313 /* same BSSID */ 314 if (memcmp(bss->cbss.bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) 315 goto put_bss; 316 317 if (rx_status->flag & RX_FLAG_TSFT) { 318 /* 319 * For correct IBSS merging we need mactime; since mactime is 320 * defined as the time the first data symbol of the frame hits 321 * the PHY, and the timestamp of the beacon is defined as "the 322 * time that the data symbol containing the first bit of the 323 * timestamp is transmitted to the PHY plus the transmitting 324 * STA's delays through its local PHY from the MAC-PHY 325 * interface to its interface with the WM" (802.11 11.1.2) 326 * - equals the time this bit arrives at the receiver - we have 327 * to take into account the offset between the two. 328 * 329 * E.g. at 1 MBit that means mactime is 192 usec earlier 330 * (=24 bytes * 8 usecs/byte) than the beacon timestamp. 331 */ 332 int rate; 333 334 if (rx_status->flag & RX_FLAG_HT) 335 rate = 65; /* TODO: HT rates */ 336 else 337 rate = local->hw.wiphy->bands[band]-> 338 bitrates[rx_status->rate_idx].bitrate; 339 340 rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate); 341 } else { 342 /* 343 * second best option: get current TSF 344 * (will return -1 if not supported) 345 */ 346 rx_timestamp = drv_get_tsf(local); 347 } 348 349#ifdef CONFIG_MAC80211_IBSS_DEBUG 350 printk(KERN_DEBUG "RX beacon SA=%pM BSSID=" 351 "%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n", 352 mgmt->sa, mgmt->bssid, 353 (unsigned long long)rx_timestamp, 354 (unsigned long long)beacon_timestamp, 355 (unsigned long long)(rx_timestamp - beacon_timestamp), 356 jiffies); 357#endif 358 359 /* give slow hardware some time to do the TSF sync */ 360 if (rx_timestamp < IEEE80211_IBSS_MERGE_DELAY) 361 goto put_bss; 362 363 if (beacon_timestamp > rx_timestamp) { 364#ifdef CONFIG_MAC80211_IBSS_DEBUG 365 printk(KERN_DEBUG "%s: beacon TSF higher than " 366 "local TSF - IBSS merge with BSSID %pM\n", 367 sdata->dev->name, mgmt->bssid); 368#endif 369 ieee80211_sta_join_ibss(sdata, bss); 370 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, supp_rates); 371 } 372 373 put_bss: 374 ieee80211_rx_bss_put(local, bss); 375} 376 377/* 378 * Add a new IBSS station, will also be called by the RX code when, 379 * in IBSS mode, receiving a frame from a yet-unknown station, hence 380 * must be callable in atomic context. 381 */ 382struct sta_info *ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, 383 u8 *bssid,u8 *addr, u32 supp_rates) 384{ 385 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 386 struct ieee80211_local *local = sdata->local; 387 struct sta_info *sta; 388 int band = local->hw.conf.channel->band; 389 390 /* 391 * XXX: Consider removing the least recently used entry and 392 * allow new one to be added. 393 */ 394 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 395 if (net_ratelimit()) 396 printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n", 397 sdata->dev->name, addr); 398 return NULL; 399 } 400 401 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) 402 return NULL; 403 404 if (compare_ether_addr(bssid, sdata->u.ibss.bssid)) 405 return NULL; 406 407#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 408 printk(KERN_DEBUG "%s: Adding new IBSS station %pM (dev=%s)\n", 409 wiphy_name(local->hw.wiphy), addr, sdata->dev->name); 410#endif 411 412 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC); 413 if (!sta) 414 return NULL; 415 416 set_sta_flags(sta, WLAN_STA_AUTHORIZED); 417 418 /* make sure mandatory rates are always added */ 419 sta->sta.supp_rates[band] = supp_rates | 420 ieee80211_mandatory_rates(local, band); 421 422 rate_control_rate_init(sta); 423 424 if (sta_info_insert(sta)) 425 return NULL; 426 427 return sta; 428} 429 430static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata) 431{ 432 struct ieee80211_local *local = sdata->local; 433 int active = 0; 434 struct sta_info *sta; 435 436 rcu_read_lock(); 437 438 list_for_each_entry_rcu(sta, &local->sta_list, list) { 439 if (sta->sdata == sdata && 440 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL, 441 jiffies)) { 442 active++; 443 break; 444 } 445 } 446 447 rcu_read_unlock(); 448 449 return active; 450} 451 452 453static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata) 454{ 455 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 456 457 mod_timer(&ifibss->timer, 458 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 459 460 ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT); 461 462 if (time_before(jiffies, ifibss->last_scan_completed + 463 IEEE80211_IBSS_MERGE_INTERVAL)) 464 return; 465 466 if (ieee80211_sta_active_ibss(sdata)) 467 return; 468 469 if (ifibss->fixed_channel) 470 return; 471 472 printk(KERN_DEBUG "%s: No active IBSS STAs - trying to scan for other " 473 "IBSS networks with same SSID (merge)\n", sdata->dev->name); 474 475 ieee80211_request_internal_scan(sdata, ifibss->ssid, ifibss->ssid_len); 476} 477 478static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata) 479{ 480 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 481 struct ieee80211_local *local = sdata->local; 482 struct ieee80211_supported_band *sband; 483 u8 bssid[ETH_ALEN]; 484 u16 capability; 485 int i; 486 487 if (ifibss->fixed_bssid) { 488 memcpy(bssid, ifibss->bssid, ETH_ALEN); 489 } else { 490 /* Generate random, not broadcast, locally administered BSSID. Mix in 491 * own MAC address to make sure that devices that do not have proper 492 * random number generator get different BSSID. */ 493 get_random_bytes(bssid, ETH_ALEN); 494 for (i = 0; i < ETH_ALEN; i++) 495 bssid[i] ^= sdata->dev->dev_addr[i]; 496 bssid[0] &= ~0x01; 497 bssid[0] |= 0x02; 498 } 499 500 printk(KERN_DEBUG "%s: Creating new IBSS network, BSSID %pM\n", 501 sdata->dev->name, bssid); 502 503 sband = local->hw.wiphy->bands[ifibss->channel->band]; 504 505 capability = WLAN_CAPABILITY_IBSS; 506 507 if (ifibss->privacy) 508 capability |= WLAN_CAPABILITY_PRIVACY; 509 else 510 sdata->drop_unencrypted = 0; 511 512 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int, 513 ifibss->channel, 3, /* first two are basic */ 514 capability, 0); 515} 516 517static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata) 518{ 519 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 520 struct ieee80211_local *local = sdata->local; 521 struct ieee80211_bss *bss; 522 struct ieee80211_channel *chan = NULL; 523 const u8 *bssid = NULL; 524 int active_ibss; 525 u16 capability; 526 527 active_ibss = ieee80211_sta_active_ibss(sdata); 528#ifdef CONFIG_MAC80211_IBSS_DEBUG 529 printk(KERN_DEBUG "%s: sta_find_ibss (active_ibss=%d)\n", 530 sdata->dev->name, active_ibss); 531#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 532 533 if (active_ibss) 534 return; 535 536 capability = WLAN_CAPABILITY_IBSS; 537 if (ifibss->privacy) 538 capability |= WLAN_CAPABILITY_PRIVACY; 539 if (ifibss->fixed_bssid) 540 bssid = ifibss->bssid; 541 if (ifibss->fixed_channel) 542 chan = ifibss->channel; 543 if (!is_zero_ether_addr(ifibss->bssid)) 544 bssid = ifibss->bssid; 545 bss = (void *)cfg80211_get_bss(local->hw.wiphy, chan, bssid, 546 ifibss->ssid, ifibss->ssid_len, 547 WLAN_CAPABILITY_IBSS | 548 WLAN_CAPABILITY_PRIVACY, 549 capability); 550 551 if (bss) { 552#ifdef CONFIG_MAC80211_IBSS_DEBUG 553 printk(KERN_DEBUG " sta_find_ibss: selected %pM current " 554 "%pM\n", bss->cbss.bssid, ifibss->bssid); 555#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 556 557 printk(KERN_DEBUG "%s: Selected IBSS BSSID %pM" 558 " based on configured SSID\n", 559 sdata->dev->name, bss->cbss.bssid); 560 561 ieee80211_sta_join_ibss(sdata, bss); 562 ieee80211_rx_bss_put(local, bss); 563 return; 564 } 565 566#ifdef CONFIG_MAC80211_IBSS_DEBUG 567 printk(KERN_DEBUG " did not try to join ibss\n"); 568#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 569 570 /* Selected IBSS not found in current scan results - try to scan */ 571 if (ifibss->state == IEEE80211_IBSS_MLME_JOINED && 572 !ieee80211_sta_active_ibss(sdata)) { 573 mod_timer(&ifibss->timer, 574 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 575 } else if (time_after(jiffies, ifibss->last_scan_completed + 576 IEEE80211_SCAN_INTERVAL)) { 577 printk(KERN_DEBUG "%s: Trigger new scan to find an IBSS to " 578 "join\n", sdata->dev->name); 579 580 ieee80211_request_internal_scan(sdata, ifibss->ssid, 581 ifibss->ssid_len); 582 } else if (ifibss->state != IEEE80211_IBSS_MLME_JOINED) { 583 int interval = IEEE80211_SCAN_INTERVAL; 584 585 if (time_after(jiffies, ifibss->ibss_join_req + 586 IEEE80211_IBSS_JOIN_TIMEOUT)) { 587 if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) { 588 ieee80211_sta_create_ibss(sdata); 589 return; 590 } 591 printk(KERN_DEBUG "%s: IBSS not allowed on" 592 " %d MHz\n", sdata->dev->name, 593 local->hw.conf.channel->center_freq); 594 595 /* No IBSS found - decrease scan interval and continue 596 * scanning. */ 597 interval = IEEE80211_SCAN_INTERVAL_SLOW; 598 } 599 600 ifibss->state = IEEE80211_IBSS_MLME_SEARCH; 601 mod_timer(&ifibss->timer, 602 round_jiffies(jiffies + interval)); 603 } 604} 605 606static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata, 607 struct ieee80211_mgmt *mgmt, 608 size_t len) 609{ 610 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 611 struct ieee80211_local *local = sdata->local; 612 int tx_last_beacon; 613 struct sk_buff *skb; 614 struct ieee80211_mgmt *resp; 615 u8 *pos, *end; 616 617 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED || 618 len < 24 + 2 || !ifibss->presp) 619 return; 620 621 tx_last_beacon = drv_tx_last_beacon(local); 622 623#ifdef CONFIG_MAC80211_IBSS_DEBUG 624 printk(KERN_DEBUG "%s: RX ProbeReq SA=%pM DA=%pM BSSID=%pM" 625 " (tx_last_beacon=%d)\n", 626 sdata->dev->name, mgmt->sa, mgmt->da, 627 mgmt->bssid, tx_last_beacon); 628#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 629 630 if (!tx_last_beacon) 631 return; 632 633 if (memcmp(mgmt->bssid, ifibss->bssid, ETH_ALEN) != 0 && 634 memcmp(mgmt->bssid, "\xff\xff\xff\xff\xff\xff", ETH_ALEN) != 0) 635 return; 636 637 end = ((u8 *) mgmt) + len; 638 pos = mgmt->u.probe_req.variable; 639 if (pos[0] != WLAN_EID_SSID || 640 pos + 2 + pos[1] > end) { 641#ifdef CONFIG_MAC80211_IBSS_DEBUG 642 printk(KERN_DEBUG "%s: Invalid SSID IE in ProbeReq " 643 "from %pM\n", 644 sdata->dev->name, mgmt->sa); 645#endif 646 return; 647 } 648 if (pos[1] != 0 && 649 (pos[1] != ifibss->ssid_len || 650 !memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) { 651 /* Ignore ProbeReq for foreign SSID */ 652 return; 653 } 654 655 /* Reply with ProbeResp */ 656 skb = skb_copy(ifibss->presp, GFP_KERNEL); 657 if (!skb) 658 return; 659 660 resp = (struct ieee80211_mgmt *) skb->data; 661 memcpy(resp->da, mgmt->sa, ETH_ALEN); 662#ifdef CONFIG_MAC80211_IBSS_DEBUG 663 printk(KERN_DEBUG "%s: Sending ProbeResp to %pM\n", 664 sdata->dev->name, resp->da); 665#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 666 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 667 ieee80211_tx_skb(sdata, skb); 668} 669 670static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata, 671 struct ieee80211_mgmt *mgmt, 672 size_t len, 673 struct ieee80211_rx_status *rx_status) 674{ 675 size_t baselen; 676 struct ieee802_11_elems elems; 677 678 if (memcmp(mgmt->da, sdata->dev->dev_addr, ETH_ALEN)) 679 return; /* ignore ProbeResp to foreign address */ 680 681 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt; 682 if (baselen > len) 683 return; 684 685 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen, 686 &elems); 687 688 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false); 689} 690 691static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 692 struct ieee80211_mgmt *mgmt, 693 size_t len, 694 struct ieee80211_rx_status *rx_status) 695{ 696 size_t baselen; 697 struct ieee802_11_elems elems; 698 699 /* Process beacon from the current BSS */ 700 baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt; 701 if (baselen > len) 702 return; 703 704 ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems); 705 706 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true); 707} 708 709static void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata, 710 struct sk_buff *skb) 711{ 712 struct ieee80211_rx_status *rx_status; 713 struct ieee80211_mgmt *mgmt; 714 u16 fc; 715 716 rx_status = IEEE80211_SKB_RXCB(skb); 717 mgmt = (struct ieee80211_mgmt *) skb->data; 718 fc = le16_to_cpu(mgmt->frame_control); 719 720 switch (fc & IEEE80211_FCTL_STYPE) { 721 case IEEE80211_STYPE_PROBE_REQ: 722 ieee80211_rx_mgmt_probe_req(sdata, mgmt, skb->len); 723 break; 724 case IEEE80211_STYPE_PROBE_RESP: 725 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len, 726 rx_status); 727 break; 728 case IEEE80211_STYPE_BEACON: 729 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len, 730 rx_status); 731 break; 732 case IEEE80211_STYPE_AUTH: 733 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len); 734 break; 735 } 736 737 kfree_skb(skb); 738} 739 740static void ieee80211_ibss_work(struct work_struct *work) 741{ 742 struct ieee80211_sub_if_data *sdata = 743 container_of(work, struct ieee80211_sub_if_data, u.ibss.work); 744 struct ieee80211_local *local = sdata->local; 745 struct ieee80211_if_ibss *ifibss; 746 struct sk_buff *skb; 747 748 if (WARN_ON(local->suspended)) 749 return; 750 751 if (!netif_running(sdata->dev)) 752 return; 753 754 if (local->scanning) 755 return; 756 757 if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_ADHOC)) 758 return; 759 ifibss = &sdata->u.ibss; 760 761 while ((skb = skb_dequeue(&ifibss->skb_queue))) 762 ieee80211_ibss_rx_queued_mgmt(sdata, skb); 763 764 if (!test_and_clear_bit(IEEE80211_IBSS_REQ_RUN, &ifibss->request)) 765 return; 766 767 switch (ifibss->state) { 768 case IEEE80211_IBSS_MLME_SEARCH: 769 ieee80211_sta_find_ibss(sdata); 770 break; 771 case IEEE80211_IBSS_MLME_JOINED: 772 ieee80211_sta_merge_ibss(sdata); 773 break; 774 default: 775 WARN_ON(1); 776 break; 777 } 778} 779 780static void ieee80211_ibss_timer(unsigned long data) 781{ 782 struct ieee80211_sub_if_data *sdata = 783 (struct ieee80211_sub_if_data *) data; 784 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 785 struct ieee80211_local *local = sdata->local; 786 787 if (local->quiescing) { 788 ifibss->timer_running = true; 789 return; 790 } 791 792 set_bit(IEEE80211_IBSS_REQ_RUN, &ifibss->request); 793 ieee80211_queue_work(&local->hw, &ifibss->work); 794} 795 796#ifdef CONFIG_PM 797void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata) 798{ 799 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 800 801 cancel_work_sync(&ifibss->work); 802 if (del_timer_sync(&ifibss->timer)) 803 ifibss->timer_running = true; 804} 805 806void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata) 807{ 808 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 809 810 if (ifibss->timer_running) { 811 add_timer(&ifibss->timer); 812 ifibss->timer_running = false; 813 } 814} 815#endif 816 817void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata) 818{ 819 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 820 821 INIT_WORK(&ifibss->work, ieee80211_ibss_work); 822 setup_timer(&ifibss->timer, ieee80211_ibss_timer, 823 (unsigned long) sdata); 824 skb_queue_head_init(&ifibss->skb_queue); 825} 826 827/* scan finished notification */ 828void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local) 829{ 830 struct ieee80211_sub_if_data *sdata; 831 832 mutex_lock(&local->iflist_mtx); 833 list_for_each_entry(sdata, &local->interfaces, list) { 834 if (!netif_running(sdata->dev)) 835 continue; 836 if (sdata->vif.type != NL80211_IFTYPE_ADHOC) 837 continue; 838 if (!sdata->u.ibss.ssid_len) 839 continue; 840 sdata->u.ibss.last_scan_completed = jiffies; 841 mod_timer(&sdata->u.ibss.timer, 0); 842 } 843 mutex_unlock(&local->iflist_mtx); 844} 845 846ieee80211_rx_result 847ieee80211_ibss_rx_mgmt(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb) 848{ 849 struct ieee80211_local *local = sdata->local; 850 struct ieee80211_mgmt *mgmt; 851 u16 fc; 852 853 if (skb->len < 24) 854 return RX_DROP_MONITOR; 855 856 mgmt = (struct ieee80211_mgmt *) skb->data; 857 fc = le16_to_cpu(mgmt->frame_control); 858 859 switch (fc & IEEE80211_FCTL_STYPE) { 860 case IEEE80211_STYPE_PROBE_RESP: 861 case IEEE80211_STYPE_BEACON: 862 case IEEE80211_STYPE_PROBE_REQ: 863 case IEEE80211_STYPE_AUTH: 864 skb_queue_tail(&sdata->u.ibss.skb_queue, skb); 865 ieee80211_queue_work(&local->hw, &sdata->u.ibss.work); 866 return RX_QUEUED; 867 } 868 869 return RX_DROP_MONITOR; 870} 871 872int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata, 873 struct cfg80211_ibss_params *params) 874{ 875 struct sk_buff *skb; 876 877 if (params->bssid) { 878 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN); 879 sdata->u.ibss.fixed_bssid = true; 880 } else 881 sdata->u.ibss.fixed_bssid = false; 882 883 sdata->u.ibss.privacy = params->privacy; 884 885 sdata->vif.bss_conf.beacon_int = params->beacon_interval; 886 887 sdata->u.ibss.channel = params->channel; 888 sdata->u.ibss.fixed_channel = params->channel_fixed; 889 890 if (params->ie) { 891 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len, 892 GFP_KERNEL); 893 if (sdata->u.ibss.ie) 894 sdata->u.ibss.ie_len = params->ie_len; 895 } 896 897 skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom + 898 36 /* bitrates */ + 899 34 /* SSID */ + 900 3 /* DS params */ + 901 4 /* IBSS params */ + 902 params->ie_len); 903 if (!skb) 904 return -ENOMEM; 905 906 sdata->u.ibss.skb = skb; 907 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; 908 sdata->u.ibss.ibss_join_req = jiffies; 909 910 memcpy(sdata->u.ibss.ssid, params->ssid, IEEE80211_MAX_SSID_LEN); 911 912 /* 913 * The ssid_len setting below is used to see whether 914 * we are active, and we need all other settings 915 * before that may get visible. 916 */ 917 mb(); 918 919 sdata->u.ibss.ssid_len = params->ssid_len; 920 921 ieee80211_recalc_idle(sdata->local); 922 923 set_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request); 924 ieee80211_queue_work(&sdata->local->hw, &sdata->u.ibss.work); 925 926 return 0; 927} 928 929int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata) 930{ 931 struct sk_buff *skb; 932 933 del_timer_sync(&sdata->u.ibss.timer); 934 clear_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request); 935 cancel_work_sync(&sdata->u.ibss.work); 936 clear_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request); 937 938 sta_info_flush(sdata->local, sdata); 939 940 /* remove beacon */ 941 kfree(sdata->u.ibss.ie); 942 skb = sdata->u.ibss.presp; 943 rcu_assign_pointer(sdata->u.ibss.presp, NULL); 944 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED); 945 synchronize_rcu(); 946 kfree_skb(skb); 947 948 skb_queue_purge(&sdata->u.ibss.skb_queue); 949 memset(sdata->u.ibss.bssid, 0, ETH_ALEN); 950 sdata->u.ibss.ssid_len = 0; 951 952 ieee80211_recalc_idle(sdata->local); 953 954 return 0; 955} 956