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 40 static 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 lockdep_assert_held(&sdata->u.ibss.mtx); 47 48 if (len < 24 + 6) 49 return; 50 51 auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg); 52 auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction); 53 status_code = le16_to_cpu(mgmt->u.auth.status_code); 54 55 /* 56 * IEEE 802.11 standard does not require authentication in IBSS 57 * networks and most implementations do not seem to use it. 58 * However, try to reply to authentication attempts if someone 59 * has actually implemented this. 60 */ 61 if (auth_alg == WLAN_AUTH_OPEN && auth_transaction == 1) 62 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, NULL, 0, 63 sdata->u.ibss.bssid, NULL, 0, 0); 64 } 65 66 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 67 const u8 *bssid, const int beacon_int, 68 struct ieee80211_channel *chan, 69 const u32 basic_rates, 70 const u16 capability, u64 tsf) 71 { 72 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 73 struct ieee80211_local *local = sdata->local; 74 int rates, i; 75 struct sk_buff *skb; 76 struct ieee80211_mgmt *mgmt; 77 u8 *pos; 78 struct ieee80211_supported_band *sband; 79 struct cfg80211_bss *bss; 80 u32 bss_change; 81 u8 supp_rates[IEEE80211_MAX_SUPP_RATES]; 82 83 lockdep_assert_held(&ifibss->mtx); 84 85 /* Reset own TSF to allow time synchronization work. */ 86 drv_reset_tsf(local); 87 88 skb = ifibss->skb; 89 rcu_assign_pointer(ifibss->presp, NULL); 90 synchronize_rcu(); 91 skb->data = skb->head; 92 skb->len = 0; 93 skb_reset_tail_pointer(skb); 94 skb_reserve(skb, sdata->local->hw.extra_tx_headroom); 95 96 if (memcmp(ifibss->bssid, bssid, ETH_ALEN)) 97 sta_info_flush(sdata->local, sdata); 98 99 /* if merging, indicate to driver that we leave the old IBSS */ 100 if (sdata->vif.bss_conf.ibss_joined) { 101 sdata->vif.bss_conf.ibss_joined = false; 102 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IBSS); 103 } 104 105 memcpy(ifibss->bssid, bssid, ETH_ALEN); 106 107 sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0; 108 109 local->oper_channel = chan; 110 WARN_ON(!ieee80211_set_channel_type(local, sdata, NL80211_CHAN_NO_HT)); 111 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); 112 113 sband = local->hw.wiphy->bands[chan->band]; 114 115 /* build supported rates array */ 116 pos = supp_rates; 117 for (i = 0; i < sband->n_bitrates; i++) { 118 int rate = sband->bitrates[i].bitrate; 119 u8 basic = 0; 120 if (basic_rates & BIT(i)) 121 basic = 0x80; 122 *pos++ = basic | (u8) (rate / 5); 123 } 124 125 /* Build IBSS probe response */ 126 mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon)); 127 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon)); 128 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 129 IEEE80211_STYPE_PROBE_RESP); 130 memset(mgmt->da, 0xff, ETH_ALEN); 131 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 132 memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN); 133 mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int); 134 mgmt->u.beacon.timestamp = cpu_to_le64(tsf); 135 mgmt->u.beacon.capab_info = cpu_to_le16(capability); 136 137 pos = skb_put(skb, 2 + ifibss->ssid_len); 138 *pos++ = WLAN_EID_SSID; 139 *pos++ = ifibss->ssid_len; 140 memcpy(pos, ifibss->ssid, ifibss->ssid_len); 141 142 rates = sband->n_bitrates; 143 if (rates > 8) 144 rates = 8; 145 pos = skb_put(skb, 2 + rates); 146 *pos++ = WLAN_EID_SUPP_RATES; 147 *pos++ = rates; 148 memcpy(pos, supp_rates, rates); 149 150 if (sband->band == IEEE80211_BAND_2GHZ) { 151 pos = skb_put(skb, 2 + 1); 152 *pos++ = WLAN_EID_DS_PARAMS; 153 *pos++ = 1; 154 *pos++ = ieee80211_frequency_to_channel(chan->center_freq); 155 } 156 157 pos = skb_put(skb, 2 + 2); 158 *pos++ = WLAN_EID_IBSS_PARAMS; 159 *pos++ = 2; 160 /* FIX: set ATIM window based on scan results */ 161 *pos++ = 0; 162 *pos++ = 0; 163 164 if (sband->n_bitrates > 8) { 165 rates = sband->n_bitrates - 8; 166 pos = skb_put(skb, 2 + rates); 167 *pos++ = WLAN_EID_EXT_SUPP_RATES; 168 *pos++ = rates; 169 memcpy(pos, &supp_rates[8], rates); 170 } 171 172 if (ifibss->ie_len) 173 memcpy(skb_put(skb, ifibss->ie_len), 174 ifibss->ie, ifibss->ie_len); 175 176 if (local->hw.queues >= 4) { 177 pos = skb_put(skb, 9); 178 *pos++ = WLAN_EID_VENDOR_SPECIFIC; 179 *pos++ = 7; /* len */ 180 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */ 181 *pos++ = 0x50; 182 *pos++ = 0xf2; 183 *pos++ = 2; /* WME */ 184 *pos++ = 0; /* WME info */ 185 *pos++ = 1; /* WME ver */ 186 *pos++ = 0; /* U-APSD no in use */ 187 } 188 189 rcu_assign_pointer(ifibss->presp, skb); 190 191 sdata->vif.bss_conf.beacon_int = beacon_int; 192 sdata->vif.bss_conf.basic_rates = basic_rates; 193 bss_change = BSS_CHANGED_BEACON_INT; 194 bss_change |= ieee80211_reset_erp_info(sdata); 195 bss_change |= BSS_CHANGED_BSSID; 196 bss_change |= BSS_CHANGED_BEACON; 197 bss_change |= BSS_CHANGED_BEACON_ENABLED; 198 bss_change |= BSS_CHANGED_BASIC_RATES; 199 bss_change |= BSS_CHANGED_IBSS; 200 sdata->vif.bss_conf.ibss_joined = true; 201 ieee80211_bss_info_change_notify(sdata, bss_change); 202 203 ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates); 204 205 ifibss->state = IEEE80211_IBSS_MLME_JOINED; 206 mod_timer(&ifibss->timer, 207 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 208 209 bss = cfg80211_inform_bss_frame(local->hw.wiphy, local->hw.conf.channel, 210 mgmt, skb->len, 0, GFP_KERNEL); 211 cfg80211_put_bss(bss); 212 cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL); 213 } 214 215 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 216 struct ieee80211_bss *bss) 217 { 218 struct cfg80211_bss *cbss = 219 container_of((void *)bss, struct cfg80211_bss, priv); 220 struct ieee80211_supported_band *sband; 221 u32 basic_rates; 222 int i, j; 223 u16 beacon_int = cbss->beacon_interval; 224 225 lockdep_assert_held(&sdata->u.ibss.mtx); 226 227 if (beacon_int < 10) 228 beacon_int = 10; 229 230 sband = sdata->local->hw.wiphy->bands[cbss->channel->band]; 231 232 basic_rates = 0; 233 234 for (i = 0; i < bss->supp_rates_len; i++) { 235 int rate = (bss->supp_rates[i] & 0x7f) * 5; 236 bool is_basic = !!(bss->supp_rates[i] & 0x80); 237 238 for (j = 0; j < sband->n_bitrates; j++) { 239 if (sband->bitrates[j].bitrate == rate) { 240 if (is_basic) 241 basic_rates |= BIT(j); 242 break; 243 } 244 } 245 } 246 247 __ieee80211_sta_join_ibss(sdata, cbss->bssid, 248 beacon_int, 249 cbss->channel, 250 basic_rates, 251 cbss->capability, 252 cbss->tsf); 253 } 254 255 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, 256 struct ieee80211_mgmt *mgmt, 257 size_t len, 258 struct ieee80211_rx_status *rx_status, 259 struct ieee802_11_elems *elems, 260 bool beacon) 261 { 262 struct ieee80211_local *local = sdata->local; 263 int freq; 264 struct cfg80211_bss *cbss; 265 struct ieee80211_bss *bss; 266 struct sta_info *sta; 267 struct ieee80211_channel *channel; 268 u64 beacon_timestamp, rx_timestamp; 269 u32 supp_rates = 0; 270 enum ieee80211_band band = rx_status->band; 271 272 if (elems->ds_params && elems->ds_params_len == 1) 273 freq = ieee80211_channel_to_frequency(elems->ds_params[0]); 274 else 275 freq = rx_status->freq; 276 277 channel = ieee80211_get_channel(local->hw.wiphy, freq); 278 279 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 280 return; 281 282 if (sdata->vif.type == NL80211_IFTYPE_ADHOC && 283 memcmp(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) { 284 285 rcu_read_lock(); 286 sta = sta_info_get(sdata, mgmt->sa); 287 288 if (elems->supp_rates) { 289 supp_rates = ieee80211_sta_get_rates(local, elems, 290 band); 291 if (sta) { 292 u32 prev_rates; 293 294 prev_rates = sta->sta.supp_rates[band]; 295 /* make sure mandatory rates are always added */ 296 sta->sta.supp_rates[band] = supp_rates | 297 ieee80211_mandatory_rates(local, band); 298 299 if (sta->sta.supp_rates[band] != prev_rates) { 300 #ifdef CONFIG_MAC80211_IBSS_DEBUG 301 printk(KERN_DEBUG 302 "%s: updated supp_rates set " 303 "for %pM based on beacon" 304 "/probe_resp (0x%x -> 0x%x)\n", 305 sdata->name, sta->sta.addr, 306 prev_rates, 307 sta->sta.supp_rates[band]); 308 #endif 309 rate_control_rate_init(sta); 310 } 311 } else 312 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, 313 mgmt->sa, supp_rates, 314 GFP_ATOMIC); 315 } 316 317 if (sta && elems->wmm_info) 318 set_sta_flags(sta, WLAN_STA_WME); 319 320 rcu_read_unlock(); 321 } 322 323 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems, 324 channel, beacon); 325 if (!bss) 326 return; 327 328 cbss = container_of((void *)bss, struct cfg80211_bss, priv); 329 330 /* was just updated in ieee80211_bss_info_update */ 331 beacon_timestamp = cbss->tsf; 332 333 /* check if we need to merge IBSS */ 334 335 /* we use a fixed BSSID */ 336 if (sdata->u.ibss.fixed_bssid) 337 goto put_bss; 338 339 /* not an IBSS */ 340 if (!(cbss->capability & WLAN_CAPABILITY_IBSS)) 341 goto put_bss; 342 343 /* different channel */ 344 if (cbss->channel != local->oper_channel) 345 goto put_bss; 346 347 /* different SSID */ 348 if (elems->ssid_len != sdata->u.ibss.ssid_len || 349 memcmp(elems->ssid, sdata->u.ibss.ssid, 350 sdata->u.ibss.ssid_len)) 351 goto put_bss; 352 353 /* same BSSID */ 354 if (memcmp(cbss->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) 355 goto put_bss; 356 357 if (rx_status->flag & RX_FLAG_TSFT) { 358 /* 359 * For correct IBSS merging we need mactime; since mactime is 360 * defined as the time the first data symbol of the frame hits 361 * the PHY, and the timestamp of the beacon is defined as "the 362 * time that the data symbol containing the first bit of the 363 * timestamp is transmitted to the PHY plus the transmitting 364 * STA's delays through its local PHY from the MAC-PHY 365 * interface to its interface with the WM" (802.11 11.1.2) 366 * - equals the time this bit arrives at the receiver - we have 367 * to take into account the offset between the two. 368 * 369 * E.g. at 1 MBit that means mactime is 192 usec earlier 370 * (=24 bytes * 8 usecs/byte) than the beacon timestamp. 371 */ 372 int rate; 373 374 if (rx_status->flag & RX_FLAG_HT) 375 rate = 65; /* TODO: HT rates */ 376 else 377 rate = local->hw.wiphy->bands[band]-> 378 bitrates[rx_status->rate_idx].bitrate; 379 380 rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate); 381 } else { 382 /* 383 * second best option: get current TSF 384 * (will return -1 if not supported) 385 */ 386 rx_timestamp = drv_get_tsf(local); 387 } 388 389 #ifdef CONFIG_MAC80211_IBSS_DEBUG 390 printk(KERN_DEBUG "RX beacon SA=%pM BSSID=" 391 "%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n", 392 mgmt->sa, mgmt->bssid, 393 (unsigned long long)rx_timestamp, 394 (unsigned long long)beacon_timestamp, 395 (unsigned long long)(rx_timestamp - beacon_timestamp), 396 jiffies); 397 #endif 398 399 /* give slow hardware some time to do the TSF sync */ 400 if (rx_timestamp < IEEE80211_IBSS_MERGE_DELAY) 401 goto put_bss; 402 403 if (beacon_timestamp > rx_timestamp) { 404 #ifdef CONFIG_MAC80211_IBSS_DEBUG 405 printk(KERN_DEBUG "%s: beacon TSF higher than " 406 "local TSF - IBSS merge with BSSID %pM\n", 407 sdata->name, mgmt->bssid); 408 #endif 409 ieee80211_sta_join_ibss(sdata, bss); 410 supp_rates = ieee80211_sta_get_rates(local, elems, band); 411 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 412 supp_rates, GFP_KERNEL); 413 } 414 415 put_bss: 416 ieee80211_rx_bss_put(local, bss); 417 } 418 419 /* 420 * Add a new IBSS station, will also be called by the RX code when, 421 * in IBSS mode, receiving a frame from a yet-unknown station, hence 422 * must be callable in atomic context. 423 */ 424 struct sta_info *ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, 425 u8 *bssid,u8 *addr, u32 supp_rates, 426 gfp_t gfp) 427 { 428 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 429 struct ieee80211_local *local = sdata->local; 430 struct sta_info *sta; 431 int band = local->hw.conf.channel->band; 432 433 /* 434 * XXX: Consider removing the least recently used entry and 435 * allow new one to be added. 436 */ 437 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 438 if (net_ratelimit()) 439 printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n", 440 sdata->name, addr); 441 return NULL; 442 } 443 444 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) 445 return NULL; 446 447 if (compare_ether_addr(bssid, sdata->u.ibss.bssid)) 448 return NULL; 449 450 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 451 wiphy_debug(local->hw.wiphy, "Adding new IBSS station %pM (dev=%s)\n", 452 addr, sdata->name); 453 #endif 454 455 sta = sta_info_alloc(sdata, addr, gfp); 456 if (!sta) 457 return NULL; 458 459 sta->last_rx = jiffies; 460 set_sta_flags(sta, WLAN_STA_AUTHORIZED); 461 462 /* make sure mandatory rates are always added */ 463 sta->sta.supp_rates[band] = supp_rates | 464 ieee80211_mandatory_rates(local, band); 465 466 rate_control_rate_init(sta); 467 468 /* If it fails, maybe we raced another insertion? */ 469 if (sta_info_insert(sta)) 470 return sta_info_get(sdata, addr); 471 return sta; 472 } 473 474 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata) 475 { 476 struct ieee80211_local *local = sdata->local; 477 int active = 0; 478 struct sta_info *sta; 479 480 lockdep_assert_held(&sdata->u.ibss.mtx); 481 482 rcu_read_lock(); 483 484 list_for_each_entry_rcu(sta, &local->sta_list, list) { 485 if (sta->sdata == sdata && 486 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL, 487 jiffies)) { 488 active++; 489 break; 490 } 491 } 492 493 rcu_read_unlock(); 494 495 return active; 496 } 497 498 /* 499 * This function is called with state == IEEE80211_IBSS_MLME_JOINED 500 */ 501 502 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata) 503 { 504 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 505 506 lockdep_assert_held(&ifibss->mtx); 507 508 mod_timer(&ifibss->timer, 509 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 510 511 ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT); 512 513 if (time_before(jiffies, ifibss->last_scan_completed + 514 IEEE80211_IBSS_MERGE_INTERVAL)) 515 return; 516 517 if (ieee80211_sta_active_ibss(sdata)) 518 return; 519 520 if (ifibss->fixed_channel) 521 return; 522 523 printk(KERN_DEBUG "%s: No active IBSS STAs - trying to scan for other " 524 "IBSS networks with same SSID (merge)\n", sdata->name); 525 526 ieee80211_request_internal_scan(sdata, 527 ifibss->ssid, ifibss->ssid_len, 528 ifibss->fixed_channel ? ifibss->channel : NULL); 529 } 530 531 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata) 532 { 533 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 534 struct ieee80211_local *local = sdata->local; 535 struct ieee80211_supported_band *sband; 536 u8 bssid[ETH_ALEN]; 537 u16 capability; 538 int i; 539 540 lockdep_assert_held(&ifibss->mtx); 541 542 if (ifibss->fixed_bssid) { 543 memcpy(bssid, ifibss->bssid, ETH_ALEN); 544 } else { 545 /* Generate random, not broadcast, locally administered BSSID. Mix in 546 * own MAC address to make sure that devices that do not have proper 547 * random number generator get different BSSID. */ 548 get_random_bytes(bssid, ETH_ALEN); 549 for (i = 0; i < ETH_ALEN; i++) 550 bssid[i] ^= sdata->vif.addr[i]; 551 bssid[0] &= ~0x01; 552 bssid[0] |= 0x02; 553 } 554 555 printk(KERN_DEBUG "%s: Creating new IBSS network, BSSID %pM\n", 556 sdata->name, bssid); 557 558 sband = local->hw.wiphy->bands[ifibss->channel->band]; 559 560 capability = WLAN_CAPABILITY_IBSS; 561 562 if (ifibss->privacy) 563 capability |= WLAN_CAPABILITY_PRIVACY; 564 else 565 sdata->drop_unencrypted = 0; 566 567 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int, 568 ifibss->channel, ifibss->basic_rates, 569 capability, 0); 570 } 571 572 /* 573 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH 574 */ 575 576 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata) 577 { 578 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 579 struct ieee80211_local *local = sdata->local; 580 struct cfg80211_bss *cbss; 581 struct ieee80211_channel *chan = NULL; 582 const u8 *bssid = NULL; 583 int active_ibss; 584 u16 capability; 585 586 lockdep_assert_held(&ifibss->mtx); 587 588 active_ibss = ieee80211_sta_active_ibss(sdata); 589 #ifdef CONFIG_MAC80211_IBSS_DEBUG 590 printk(KERN_DEBUG "%s: sta_find_ibss (active_ibss=%d)\n", 591 sdata->name, active_ibss); 592 #endif /* CONFIG_MAC80211_IBSS_DEBUG */ 593 594 if (active_ibss) 595 return; 596 597 capability = WLAN_CAPABILITY_IBSS; 598 if (ifibss->privacy) 599 capability |= WLAN_CAPABILITY_PRIVACY; 600 if (ifibss->fixed_bssid) 601 bssid = ifibss->bssid; 602 if (ifibss->fixed_channel) 603 chan = ifibss->channel; 604 if (!is_zero_ether_addr(ifibss->bssid)) 605 bssid = ifibss->bssid; 606 cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid, 607 ifibss->ssid, ifibss->ssid_len, 608 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY, 609 capability); 610 611 if (cbss) { 612 struct ieee80211_bss *bss; 613 614 bss = (void *)cbss->priv; 615 #ifdef CONFIG_MAC80211_IBSS_DEBUG 616 printk(KERN_DEBUG " sta_find_ibss: selected %pM current " 617 "%pM\n", cbss->bssid, ifibss->bssid); 618 #endif /* CONFIG_MAC80211_IBSS_DEBUG */ 619 620 printk(KERN_DEBUG "%s: Selected IBSS BSSID %pM" 621 " based on configured SSID\n", 622 sdata->name, cbss->bssid); 623 624 ieee80211_sta_join_ibss(sdata, bss); 625 ieee80211_rx_bss_put(local, bss); 626 return; 627 } 628 629 #ifdef CONFIG_MAC80211_IBSS_DEBUG 630 printk(KERN_DEBUG " did not try to join ibss\n"); 631 #endif /* CONFIG_MAC80211_IBSS_DEBUG */ 632 633 /* Selected IBSS not found in current scan results - try to scan */ 634 if (time_after(jiffies, ifibss->last_scan_completed + 635 IEEE80211_SCAN_INTERVAL)) { 636 printk(KERN_DEBUG "%s: Trigger new scan to find an IBSS to " 637 "join\n", sdata->name); 638 639 ieee80211_request_internal_scan(sdata, 640 ifibss->ssid, ifibss->ssid_len, 641 ifibss->fixed_channel ? ifibss->channel : NULL); 642 } else { 643 int interval = IEEE80211_SCAN_INTERVAL; 644 645 if (time_after(jiffies, ifibss->ibss_join_req + 646 IEEE80211_IBSS_JOIN_TIMEOUT)) { 647 if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) { 648 ieee80211_sta_create_ibss(sdata); 649 return; 650 } 651 printk(KERN_DEBUG "%s: IBSS not allowed on" 652 " %d MHz\n", sdata->name, 653 local->hw.conf.channel->center_freq); 654 655 /* No IBSS found - decrease scan interval and continue 656 * scanning. */ 657 interval = IEEE80211_SCAN_INTERVAL_SLOW; 658 } 659 660 mod_timer(&ifibss->timer, 661 round_jiffies(jiffies + interval)); 662 } 663 } 664 665 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata, 666 struct ieee80211_mgmt *mgmt, 667 size_t len) 668 { 669 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 670 struct ieee80211_local *local = sdata->local; 671 int tx_last_beacon; 672 struct sk_buff *skb; 673 struct ieee80211_mgmt *resp; 674 u8 *pos, *end; 675 676 lockdep_assert_held(&ifibss->mtx); 677 678 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED || 679 len < 24 + 2 || !ifibss->presp) 680 return; 681 682 tx_last_beacon = drv_tx_last_beacon(local); 683 684 #ifdef CONFIG_MAC80211_IBSS_DEBUG 685 printk(KERN_DEBUG "%s: RX ProbeReq SA=%pM DA=%pM BSSID=%pM" 686 " (tx_last_beacon=%d)\n", 687 sdata->name, mgmt->sa, mgmt->da, 688 mgmt->bssid, tx_last_beacon); 689 #endif /* CONFIG_MAC80211_IBSS_DEBUG */ 690 691 if (!tx_last_beacon) 692 return; 693 694 if (memcmp(mgmt->bssid, ifibss->bssid, ETH_ALEN) != 0 && 695 memcmp(mgmt->bssid, "\xff\xff\xff\xff\xff\xff", ETH_ALEN) != 0) 696 return; 697 698 end = ((u8 *) mgmt) + len; 699 pos = mgmt->u.probe_req.variable; 700 if (pos[0] != WLAN_EID_SSID || 701 pos + 2 + pos[1] > end) { 702 #ifdef CONFIG_MAC80211_IBSS_DEBUG 703 printk(KERN_DEBUG "%s: Invalid SSID IE in ProbeReq " 704 "from %pM\n", 705 sdata->name, mgmt->sa); 706 #endif 707 return; 708 } 709 if (pos[1] != 0 && 710 (pos[1] != ifibss->ssid_len || 711 memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) { 712 /* Ignore ProbeReq for foreign SSID */ 713 return; 714 } 715 716 /* Reply with ProbeResp */ 717 skb = skb_copy(ifibss->presp, GFP_KERNEL); 718 if (!skb) 719 return; 720 721 resp = (struct ieee80211_mgmt *) skb->data; 722 memcpy(resp->da, mgmt->sa, ETH_ALEN); 723 #ifdef CONFIG_MAC80211_IBSS_DEBUG 724 printk(KERN_DEBUG "%s: Sending ProbeResp to %pM\n", 725 sdata->name, resp->da); 726 #endif /* CONFIG_MAC80211_IBSS_DEBUG */ 727 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 728 ieee80211_tx_skb(sdata, skb); 729 } 730 731 static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata, 732 struct ieee80211_mgmt *mgmt, 733 size_t len, 734 struct ieee80211_rx_status *rx_status) 735 { 736 size_t baselen; 737 struct ieee802_11_elems elems; 738 739 if (memcmp(mgmt->da, sdata->vif.addr, ETH_ALEN)) 740 return; /* ignore ProbeResp to foreign address */ 741 742 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt; 743 if (baselen > len) 744 return; 745 746 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen, 747 &elems); 748 749 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false); 750 } 751 752 static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 753 struct ieee80211_mgmt *mgmt, 754 size_t len, 755 struct ieee80211_rx_status *rx_status) 756 { 757 size_t baselen; 758 struct ieee802_11_elems elems; 759 760 /* Process beacon from the current BSS */ 761 baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt; 762 if (baselen > len) 763 return; 764 765 ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems); 766 767 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true); 768 } 769 770 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata, 771 struct sk_buff *skb) 772 { 773 struct ieee80211_rx_status *rx_status; 774 struct ieee80211_mgmt *mgmt; 775 u16 fc; 776 777 rx_status = IEEE80211_SKB_RXCB(skb); 778 mgmt = (struct ieee80211_mgmt *) skb->data; 779 fc = le16_to_cpu(mgmt->frame_control); 780 781 mutex_lock(&sdata->u.ibss.mtx); 782 783 if (!sdata->u.ibss.ssid_len) 784 goto mgmt_out; /* not ready to merge yet */ 785 786 switch (fc & IEEE80211_FCTL_STYPE) { 787 case IEEE80211_STYPE_PROBE_REQ: 788 ieee80211_rx_mgmt_probe_req(sdata, mgmt, skb->len); 789 break; 790 case IEEE80211_STYPE_PROBE_RESP: 791 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len, 792 rx_status); 793 break; 794 case IEEE80211_STYPE_BEACON: 795 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len, 796 rx_status); 797 break; 798 case IEEE80211_STYPE_AUTH: 799 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len); 800 break; 801 } 802 803 mgmt_out: 804 mutex_unlock(&sdata->u.ibss.mtx); 805 } 806 807 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata) 808 { 809 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 810 811 mutex_lock(&ifibss->mtx); 812 813 /* 814 * Work could be scheduled after scan or similar 815 * when we aren't even joined (or trying) with a 816 * network. 817 */ 818 if (!ifibss->ssid_len) 819 goto out; 820 821 switch (ifibss->state) { 822 case IEEE80211_IBSS_MLME_SEARCH: 823 ieee80211_sta_find_ibss(sdata); 824 break; 825 case IEEE80211_IBSS_MLME_JOINED: 826 ieee80211_sta_merge_ibss(sdata); 827 break; 828 default: 829 WARN_ON(1); 830 break; 831 } 832 833 out: 834 mutex_unlock(&ifibss->mtx); 835 } 836 837 static void ieee80211_ibss_timer(unsigned long data) 838 { 839 struct ieee80211_sub_if_data *sdata = 840 (struct ieee80211_sub_if_data *) data; 841 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 842 struct ieee80211_local *local = sdata->local; 843 844 if (local->quiescing) { 845 ifibss->timer_running = true; 846 return; 847 } 848 849 ieee80211_queue_work(&local->hw, &sdata->work); 850 } 851 852 #ifdef CONFIG_PM 853 void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata) 854 { 855 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 856 857 if (del_timer_sync(&ifibss->timer)) 858 ifibss->timer_running = true; 859 } 860 861 void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata) 862 { 863 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 864 865 if (ifibss->timer_running) { 866 add_timer(&ifibss->timer); 867 ifibss->timer_running = false; 868 } 869 } 870 #endif 871 872 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata) 873 { 874 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 875 876 setup_timer(&ifibss->timer, ieee80211_ibss_timer, 877 (unsigned long) sdata); 878 mutex_init(&ifibss->mtx); 879 } 880 881 /* scan finished notification */ 882 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local) 883 { 884 struct ieee80211_sub_if_data *sdata; 885 886 mutex_lock(&local->iflist_mtx); 887 list_for_each_entry(sdata, &local->interfaces, list) { 888 if (!ieee80211_sdata_running(sdata)) 889 continue; 890 if (sdata->vif.type != NL80211_IFTYPE_ADHOC) 891 continue; 892 sdata->u.ibss.last_scan_completed = jiffies; 893 ieee80211_queue_work(&local->hw, &sdata->work); 894 } 895 mutex_unlock(&local->iflist_mtx); 896 } 897 898 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata, 899 struct cfg80211_ibss_params *params) 900 { 901 struct sk_buff *skb; 902 903 skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom + 904 36 /* bitrates */ + 905 34 /* SSID */ + 906 3 /* DS params */ + 907 4 /* IBSS params */ + 908 params->ie_len); 909 if (!skb) 910 return -ENOMEM; 911 912 mutex_lock(&sdata->u.ibss.mtx); 913 914 if (params->bssid) { 915 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN); 916 sdata->u.ibss.fixed_bssid = true; 917 } else 918 sdata->u.ibss.fixed_bssid = false; 919 920 sdata->u.ibss.privacy = params->privacy; 921 sdata->u.ibss.basic_rates = params->basic_rates; 922 memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate, 923 sizeof(params->mcast_rate)); 924 925 sdata->vif.bss_conf.beacon_int = params->beacon_interval; 926 927 sdata->u.ibss.channel = params->channel; 928 sdata->u.ibss.fixed_channel = params->channel_fixed; 929 930 /* fix ourselves to that channel now already */ 931 if (params->channel_fixed) { 932 sdata->local->oper_channel = params->channel; 933 WARN_ON(!ieee80211_set_channel_type(sdata->local, sdata, 934 NL80211_CHAN_NO_HT)); 935 } 936 937 if (params->ie) { 938 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len, 939 GFP_KERNEL); 940 if (sdata->u.ibss.ie) 941 sdata->u.ibss.ie_len = params->ie_len; 942 } 943 944 sdata->u.ibss.skb = skb; 945 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; 946 sdata->u.ibss.ibss_join_req = jiffies; 947 948 memcpy(sdata->u.ibss.ssid, params->ssid, IEEE80211_MAX_SSID_LEN); 949 sdata->u.ibss.ssid_len = params->ssid_len; 950 951 mutex_unlock(&sdata->u.ibss.mtx); 952 953 mutex_lock(&sdata->local->mtx); 954 ieee80211_recalc_idle(sdata->local); 955 mutex_unlock(&sdata->local->mtx); 956 957 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 958 959 return 0; 960 } 961 962 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata) 963 { 964 struct sk_buff *skb; 965 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 966 struct ieee80211_local *local = sdata->local; 967 struct cfg80211_bss *cbss; 968 u16 capability; 969 int active_ibss; 970 971 mutex_lock(&sdata->u.ibss.mtx); 972 973 active_ibss = ieee80211_sta_active_ibss(sdata); 974 975 if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) { 976 capability = WLAN_CAPABILITY_IBSS; 977 978 if (ifibss->privacy) 979 capability |= WLAN_CAPABILITY_PRIVACY; 980 981 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel, 982 ifibss->bssid, ifibss->ssid, 983 ifibss->ssid_len, WLAN_CAPABILITY_IBSS | 984 WLAN_CAPABILITY_PRIVACY, 985 capability); 986 987 if (cbss) { 988 cfg80211_unlink_bss(local->hw.wiphy, cbss); 989 cfg80211_put_bss(cbss); 990 } 991 } 992 993 sta_info_flush(sdata->local, sdata); 994 995 /* remove beacon */ 996 kfree(sdata->u.ibss.ie); 997 skb = sdata->u.ibss.presp; 998 rcu_assign_pointer(sdata->u.ibss.presp, NULL); 999 sdata->vif.bss_conf.ibss_joined = false; 1000 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED | 1001 BSS_CHANGED_IBSS); 1002 synchronize_rcu(); 1003 kfree_skb(skb); 1004 1005 skb_queue_purge(&sdata->skb_queue); 1006 memset(sdata->u.ibss.bssid, 0, ETH_ALEN); 1007 sdata->u.ibss.ssid_len = 0; 1008 1009 del_timer_sync(&sdata->u.ibss.timer); 1010 1011 mutex_unlock(&sdata->u.ibss.mtx); 1012 1013 mutex_lock(&local->mtx); 1014 ieee80211_recalc_idle(sdata->local); 1015 mutex_unlock(&local->mtx); 1016 1017 return 0; 1018 } 1019