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 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_INACTIVITY_LIMIT (60 * HZ) 34 35 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128 36 37 38 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 39 const u8 *bssid, const int beacon_int, 40 struct ieee80211_channel *chan, 41 const u32 basic_rates, 42 const u16 capability, u64 tsf) 43 { 44 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 45 struct ieee80211_local *local = sdata->local; 46 int rates, i; 47 struct sk_buff *skb; 48 struct ieee80211_mgmt *mgmt; 49 u8 *pos; 50 struct ieee80211_supported_band *sband; 51 struct cfg80211_bss *bss; 52 u32 bss_change; 53 u8 supp_rates[IEEE80211_MAX_SUPP_RATES]; 54 enum nl80211_channel_type channel_type; 55 56 lockdep_assert_held(&ifibss->mtx); 57 58 /* Reset own TSF to allow time synchronization work. */ 59 drv_reset_tsf(local, sdata); 60 61 skb = ifibss->skb; 62 RCU_INIT_POINTER(ifibss->presp, NULL); 63 synchronize_rcu(); 64 skb->data = skb->head; 65 skb->len = 0; 66 skb_reset_tail_pointer(skb); 67 skb_reserve(skb, sdata->local->hw.extra_tx_headroom); 68 69 if (compare_ether_addr(ifibss->bssid, bssid)) 70 sta_info_flush(sdata->local, sdata); 71 72 /* if merging, indicate to driver that we leave the old IBSS */ 73 if (sdata->vif.bss_conf.ibss_joined) { 74 sdata->vif.bss_conf.ibss_joined = false; 75 netif_carrier_off(sdata->dev); 76 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IBSS); 77 } 78 79 memcpy(ifibss->bssid, bssid, ETH_ALEN); 80 81 sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0; 82 83 local->oper_channel = chan; 84 channel_type = ifibss->channel_type; 85 if (channel_type > NL80211_CHAN_HT20 && 86 !cfg80211_can_beacon_sec_chan(local->hw.wiphy, chan, channel_type)) 87 channel_type = NL80211_CHAN_HT20; 88 if (!ieee80211_set_channel_type(local, sdata, channel_type)) { 89 /* can only fail due to HT40+/- mismatch */ 90 channel_type = NL80211_CHAN_HT20; 91 WARN_ON(!ieee80211_set_channel_type(local, sdata, 92 NL80211_CHAN_HT20)); 93 } 94 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); 95 96 sband = local->hw.wiphy->bands[chan->band]; 97 98 /* build supported rates array */ 99 pos = supp_rates; 100 for (i = 0; i < sband->n_bitrates; i++) { 101 int rate = sband->bitrates[i].bitrate; 102 u8 basic = 0; 103 if (basic_rates & BIT(i)) 104 basic = 0x80; 105 *pos++ = basic | (u8) (rate / 5); 106 } 107 108 /* Build IBSS probe response */ 109 mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon)); 110 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon)); 111 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 112 IEEE80211_STYPE_PROBE_RESP); 113 memset(mgmt->da, 0xff, ETH_ALEN); 114 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 115 memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN); 116 mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int); 117 mgmt->u.beacon.timestamp = cpu_to_le64(tsf); 118 mgmt->u.beacon.capab_info = cpu_to_le16(capability); 119 120 pos = skb_put(skb, 2 + ifibss->ssid_len); 121 *pos++ = WLAN_EID_SSID; 122 *pos++ = ifibss->ssid_len; 123 memcpy(pos, ifibss->ssid, ifibss->ssid_len); 124 125 rates = sband->n_bitrates; 126 if (rates > 8) 127 rates = 8; 128 pos = skb_put(skb, 2 + rates); 129 *pos++ = WLAN_EID_SUPP_RATES; 130 *pos++ = rates; 131 memcpy(pos, supp_rates, rates); 132 133 if (sband->band == IEEE80211_BAND_2GHZ) { 134 pos = skb_put(skb, 2 + 1); 135 *pos++ = WLAN_EID_DS_PARAMS; 136 *pos++ = 1; 137 *pos++ = ieee80211_frequency_to_channel(chan->center_freq); 138 } 139 140 pos = skb_put(skb, 2 + 2); 141 *pos++ = WLAN_EID_IBSS_PARAMS; 142 *pos++ = 2; 143 /* FIX: set ATIM window based on scan results */ 144 *pos++ = 0; 145 *pos++ = 0; 146 147 if (sband->n_bitrates > 8) { 148 rates = sband->n_bitrates - 8; 149 pos = skb_put(skb, 2 + rates); 150 *pos++ = WLAN_EID_EXT_SUPP_RATES; 151 *pos++ = rates; 152 memcpy(pos, &supp_rates[8], rates); 153 } 154 155 if (ifibss->ie_len) 156 memcpy(skb_put(skb, ifibss->ie_len), 157 ifibss->ie, ifibss->ie_len); 158 159 /* add HT capability and information IEs */ 160 if (channel_type && sband->ht_cap.ht_supported) { 161 pos = skb_put(skb, 4 + 162 sizeof(struct ieee80211_ht_cap) + 163 sizeof(struct ieee80211_ht_info)); 164 pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap, 165 sband->ht_cap.cap); 166 pos = ieee80211_ie_build_ht_info(pos, 167 &sband->ht_cap, 168 chan, 169 channel_type); 170 } 171 172 if (local->hw.queues >= 4) { 173 pos = skb_put(skb, 9); 174 *pos++ = WLAN_EID_VENDOR_SPECIFIC; 175 *pos++ = 7; /* len */ 176 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */ 177 *pos++ = 0x50; 178 *pos++ = 0xf2; 179 *pos++ = 2; /* WME */ 180 *pos++ = 0; /* WME info */ 181 *pos++ = 1; /* WME ver */ 182 *pos++ = 0; /* U-APSD no in use */ 183 } 184 185 rcu_assign_pointer(ifibss->presp, skb); 186 187 sdata->vif.bss_conf.beacon_int = beacon_int; 188 sdata->vif.bss_conf.basic_rates = basic_rates; 189 bss_change = BSS_CHANGED_BEACON_INT; 190 bss_change |= ieee80211_reset_erp_info(sdata); 191 bss_change |= BSS_CHANGED_BSSID; 192 bss_change |= BSS_CHANGED_BEACON; 193 bss_change |= BSS_CHANGED_BEACON_ENABLED; 194 bss_change |= BSS_CHANGED_BASIC_RATES; 195 bss_change |= BSS_CHANGED_HT; 196 bss_change |= BSS_CHANGED_IBSS; 197 sdata->vif.bss_conf.ibss_joined = true; 198 ieee80211_bss_info_change_notify(sdata, bss_change); 199 200 ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates); 201 202 ifibss->state = IEEE80211_IBSS_MLME_JOINED; 203 mod_timer(&ifibss->timer, 204 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 205 206 bss = cfg80211_inform_bss_frame(local->hw.wiphy, local->hw.conf.channel, 207 mgmt, skb->len, 0, GFP_KERNEL); 208 cfg80211_put_bss(bss); 209 netif_carrier_on(sdata->dev); 210 cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL); 211 } 212 213 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 214 struct ieee80211_bss *bss) 215 { 216 struct cfg80211_bss *cbss = 217 container_of((void *)bss, struct cfg80211_bss, priv); 218 struct ieee80211_supported_band *sband; 219 u32 basic_rates; 220 int i, j; 221 u16 beacon_int = cbss->beacon_interval; 222 223 lockdep_assert_held(&sdata->u.ibss.mtx); 224 225 if (beacon_int < 10) 226 beacon_int = 10; 227 228 sband = sdata->local->hw.wiphy->bands[cbss->channel->band]; 229 230 basic_rates = 0; 231 232 for (i = 0; i < bss->supp_rates_len; i++) { 233 int rate = (bss->supp_rates[i] & 0x7f) * 5; 234 bool is_basic = !!(bss->supp_rates[i] & 0x80); 235 236 for (j = 0; j < sband->n_bitrates; j++) { 237 if (sband->bitrates[j].bitrate == rate) { 238 if (is_basic) 239 basic_rates |= BIT(j); 240 break; 241 } 242 } 243 } 244 245 __ieee80211_sta_join_ibss(sdata, cbss->bssid, 246 beacon_int, 247 cbss->channel, 248 basic_rates, 249 cbss->capability, 250 cbss->tsf); 251 } 252 253 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta, 254 bool auth) 255 __acquires(RCU) 256 { 257 struct ieee80211_sub_if_data *sdata = sta->sdata; 258 u8 addr[ETH_ALEN]; 259 260 memcpy(addr, sta->sta.addr, ETH_ALEN); 261 262 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 263 wiphy_debug(sdata->local->hw.wiphy, 264 "Adding new IBSS station %pM (dev=%s)\n", 265 addr, sdata->name); 266 #endif 267 268 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH); 269 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC); 270 /* authorize the station only if the network is not RSN protected. If 271 * not wait for the userspace to authorize it */ 272 if (!sta->sdata->u.ibss.control_port) 273 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED); 274 275 rate_control_rate_init(sta); 276 277 /* If it fails, maybe we raced another insertion? */ 278 if (sta_info_insert_rcu(sta)) 279 return sta_info_get(sdata, addr); 280 if (auth) { 281 #ifdef CONFIG_MAC80211_IBSS_DEBUG 282 printk(KERN_DEBUG "TX Auth SA=%pM DA=%pM BSSID=%pM" 283 "(auth_transaction=1)\n", sdata->vif.addr, 284 sdata->u.ibss.bssid, addr); 285 #endif 286 ieee80211_send_auth(sdata, 1, WLAN_AUTH_OPEN, NULL, 0, 287 addr, sdata->u.ibss.bssid, NULL, 0, 0); 288 } 289 return sta; 290 } 291 292 static struct sta_info * 293 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, 294 const u8 *bssid, const u8 *addr, 295 u32 supp_rates, bool auth) 296 __acquires(RCU) 297 { 298 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 299 struct ieee80211_local *local = sdata->local; 300 struct sta_info *sta; 301 int band = local->hw.conf.channel->band; 302 303 /* 304 * XXX: Consider removing the least recently used entry and 305 * allow new one to be added. 306 */ 307 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 308 if (net_ratelimit()) 309 printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n", 310 sdata->name, addr); 311 rcu_read_lock(); 312 return NULL; 313 } 314 315 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) { 316 rcu_read_lock(); 317 return NULL; 318 } 319 320 if (compare_ether_addr(bssid, sdata->u.ibss.bssid)) { 321 rcu_read_lock(); 322 return NULL; 323 } 324 325 sta = sta_info_alloc(sdata, addr, GFP_KERNEL); 326 if (!sta) { 327 rcu_read_lock(); 328 return NULL; 329 } 330 331 sta->last_rx = jiffies; 332 333 /* make sure mandatory rates are always added */ 334 sta->sta.supp_rates[band] = supp_rates | 335 ieee80211_mandatory_rates(local, band); 336 337 return ieee80211_ibss_finish_sta(sta, auth); 338 } 339 340 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata, 341 struct ieee80211_mgmt *mgmt, 342 size_t len) 343 { 344 u16 auth_alg, auth_transaction; 345 346 lockdep_assert_held(&sdata->u.ibss.mtx); 347 348 if (len < 24 + 6) 349 return; 350 351 auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg); 352 auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction); 353 354 if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1) 355 return; 356 #ifdef CONFIG_MAC80211_IBSS_DEBUG 357 printk(KERN_DEBUG "%s: RX Auth SA=%pM DA=%pM BSSID=%pM." 358 "(auth_transaction=%d)\n", 359 sdata->name, mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction); 360 #endif 361 sta_info_destroy_addr(sdata, mgmt->sa); 362 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 0, false); 363 rcu_read_unlock(); 364 365 /* 366 * IEEE 802.11 standard does not require authentication in IBSS 367 * networks and most implementations do not seem to use it. 368 * However, try to reply to authentication attempts if someone 369 * has actually implemented this. 370 */ 371 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, NULL, 0, 372 mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0); 373 } 374 375 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, 376 struct ieee80211_mgmt *mgmt, 377 size_t len, 378 struct ieee80211_rx_status *rx_status, 379 struct ieee802_11_elems *elems, 380 bool beacon) 381 { 382 struct ieee80211_local *local = sdata->local; 383 int freq; 384 struct cfg80211_bss *cbss; 385 struct ieee80211_bss *bss; 386 struct sta_info *sta; 387 struct ieee80211_channel *channel; 388 u64 beacon_timestamp, rx_timestamp; 389 u32 supp_rates = 0; 390 enum ieee80211_band band = rx_status->band; 391 struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band]; 392 bool rates_updated = false; 393 394 if (elems->ds_params && elems->ds_params_len == 1) 395 freq = ieee80211_channel_to_frequency(elems->ds_params[0], 396 band); 397 else 398 freq = rx_status->freq; 399 400 channel = ieee80211_get_channel(local->hw.wiphy, freq); 401 402 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 403 return; 404 405 if (sdata->vif.type == NL80211_IFTYPE_ADHOC && 406 compare_ether_addr(mgmt->bssid, sdata->u.ibss.bssid) == 0) { 407 408 rcu_read_lock(); 409 sta = sta_info_get(sdata, mgmt->sa); 410 411 if (elems->supp_rates) { 412 supp_rates = ieee80211_sta_get_rates(local, elems, 413 band); 414 if (sta) { 415 u32 prev_rates; 416 417 prev_rates = sta->sta.supp_rates[band]; 418 /* make sure mandatory rates are always added */ 419 sta->sta.supp_rates[band] = supp_rates | 420 ieee80211_mandatory_rates(local, band); 421 422 if (sta->sta.supp_rates[band] != prev_rates) { 423 #ifdef CONFIG_MAC80211_IBSS_DEBUG 424 printk(KERN_DEBUG 425 "%s: updated supp_rates set " 426 "for %pM based on beacon" 427 "/probe_resp (0x%x -> 0x%x)\n", 428 sdata->name, sta->sta.addr, 429 prev_rates, 430 sta->sta.supp_rates[band]); 431 #endif 432 rates_updated = true; 433 } 434 } else { 435 rcu_read_unlock(); 436 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, 437 mgmt->sa, supp_rates, true); 438 } 439 } 440 441 if (sta && elems->wmm_info) 442 set_sta_flag(sta, WLAN_STA_WME); 443 444 if (sta && elems->ht_info_elem && elems->ht_cap_elem && 445 sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) { 446 /* we both use HT */ 447 struct ieee80211_sta_ht_cap sta_ht_cap_new; 448 enum nl80211_channel_type channel_type = 449 ieee80211_ht_info_to_channel_type( 450 elems->ht_info_elem); 451 452 ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband, 453 elems->ht_cap_elem, 454 &sta_ht_cap_new); 455 456 /* 457 * fall back to HT20 if we don't use or use 458 * the other extension channel 459 */ 460 if (!(channel_type == NL80211_CHAN_HT40MINUS || 461 channel_type == NL80211_CHAN_HT40PLUS) || 462 channel_type != sdata->u.ibss.channel_type) 463 sta_ht_cap_new.cap &= 464 ~IEEE80211_HT_CAP_SUP_WIDTH_20_40; 465 466 if (memcmp(&sta->sta.ht_cap, &sta_ht_cap_new, 467 sizeof(sta_ht_cap_new))) { 468 memcpy(&sta->sta.ht_cap, &sta_ht_cap_new, 469 sizeof(sta_ht_cap_new)); 470 rates_updated = true; 471 } 472 } 473 474 if (sta && rates_updated) 475 rate_control_rate_init(sta); 476 477 rcu_read_unlock(); 478 } 479 480 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems, 481 channel, beacon); 482 if (!bss) 483 return; 484 485 cbss = container_of((void *)bss, struct cfg80211_bss, priv); 486 487 /* was just updated in ieee80211_bss_info_update */ 488 beacon_timestamp = cbss->tsf; 489 490 /* check if we need to merge IBSS */ 491 492 /* we use a fixed BSSID */ 493 if (sdata->u.ibss.fixed_bssid) 494 goto put_bss; 495 496 /* not an IBSS */ 497 if (!(cbss->capability & WLAN_CAPABILITY_IBSS)) 498 goto put_bss; 499 500 /* different channel */ 501 if (cbss->channel != local->oper_channel) 502 goto put_bss; 503 504 /* different SSID */ 505 if (elems->ssid_len != sdata->u.ibss.ssid_len || 506 memcmp(elems->ssid, sdata->u.ibss.ssid, 507 sdata->u.ibss.ssid_len)) 508 goto put_bss; 509 510 /* same BSSID */ 511 if (compare_ether_addr(cbss->bssid, sdata->u.ibss.bssid) == 0) 512 goto put_bss; 513 514 if (rx_status->flag & RX_FLAG_MACTIME_MPDU) { 515 /* 516 * For correct IBSS merging we need mactime; since mactime is 517 * defined as the time the first data symbol of the frame hits 518 * the PHY, and the timestamp of the beacon is defined as "the 519 * time that the data symbol containing the first bit of the 520 * timestamp is transmitted to the PHY plus the transmitting 521 * STA's delays through its local PHY from the MAC-PHY 522 * interface to its interface with the WM" (802.11 11.1.2) 523 * - equals the time this bit arrives at the receiver - we have 524 * to take into account the offset between the two. 525 * 526 * E.g. at 1 MBit that means mactime is 192 usec earlier 527 * (=24 bytes * 8 usecs/byte) than the beacon timestamp. 528 */ 529 int rate; 530 531 if (rx_status->flag & RX_FLAG_HT) 532 rate = 65; /* TODO: HT rates */ 533 else 534 rate = local->hw.wiphy->bands[band]-> 535 bitrates[rx_status->rate_idx].bitrate; 536 537 rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate); 538 } else { 539 /* 540 * second best option: get current TSF 541 * (will return -1 if not supported) 542 */ 543 rx_timestamp = drv_get_tsf(local, sdata); 544 } 545 546 #ifdef CONFIG_MAC80211_IBSS_DEBUG 547 printk(KERN_DEBUG "RX beacon SA=%pM BSSID=" 548 "%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n", 549 mgmt->sa, mgmt->bssid, 550 (unsigned long long)rx_timestamp, 551 (unsigned long long)beacon_timestamp, 552 (unsigned long long)(rx_timestamp - beacon_timestamp), 553 jiffies); 554 #endif 555 556 if (beacon_timestamp > rx_timestamp) { 557 #ifdef CONFIG_MAC80211_IBSS_DEBUG 558 printk(KERN_DEBUG "%s: beacon TSF higher than " 559 "local TSF - IBSS merge with BSSID %pM\n", 560 sdata->name, mgmt->bssid); 561 #endif 562 ieee80211_sta_join_ibss(sdata, bss); 563 supp_rates = ieee80211_sta_get_rates(local, elems, band); 564 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 565 supp_rates, true); 566 rcu_read_unlock(); 567 } 568 569 put_bss: 570 ieee80211_rx_bss_put(local, bss); 571 } 572 573 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata, 574 const u8 *bssid, const u8 *addr, 575 u32 supp_rates) 576 { 577 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 578 struct ieee80211_local *local = sdata->local; 579 struct sta_info *sta; 580 int band = local->hw.conf.channel->band; 581 582 /* 583 * XXX: Consider removing the least recently used entry and 584 * allow new one to be added. 585 */ 586 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 587 if (net_ratelimit()) 588 printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n", 589 sdata->name, addr); 590 return; 591 } 592 593 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) 594 return; 595 596 if (compare_ether_addr(bssid, sdata->u.ibss.bssid)) 597 return; 598 599 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC); 600 if (!sta) 601 return; 602 603 sta->last_rx = jiffies; 604 605 /* make sure mandatory rates are always added */ 606 sta->sta.supp_rates[band] = supp_rates | 607 ieee80211_mandatory_rates(local, band); 608 609 spin_lock(&ifibss->incomplete_lock); 610 list_add(&sta->list, &ifibss->incomplete_stations); 611 spin_unlock(&ifibss->incomplete_lock); 612 ieee80211_queue_work(&local->hw, &sdata->work); 613 } 614 615 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata) 616 { 617 struct ieee80211_local *local = sdata->local; 618 int active = 0; 619 struct sta_info *sta; 620 621 lockdep_assert_held(&sdata->u.ibss.mtx); 622 623 rcu_read_lock(); 624 625 list_for_each_entry_rcu(sta, &local->sta_list, list) { 626 if (sta->sdata == sdata && 627 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL, 628 jiffies)) { 629 active++; 630 break; 631 } 632 } 633 634 rcu_read_unlock(); 635 636 return active; 637 } 638 639 /* 640 * This function is called with state == IEEE80211_IBSS_MLME_JOINED 641 */ 642 643 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata) 644 { 645 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 646 647 lockdep_assert_held(&ifibss->mtx); 648 649 mod_timer(&ifibss->timer, 650 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 651 652 ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT); 653 654 if (time_before(jiffies, ifibss->last_scan_completed + 655 IEEE80211_IBSS_MERGE_INTERVAL)) 656 return; 657 658 if (ieee80211_sta_active_ibss(sdata)) 659 return; 660 661 if (ifibss->fixed_channel) 662 return; 663 664 printk(KERN_DEBUG "%s: No active IBSS STAs - trying to scan for other " 665 "IBSS networks with same SSID (merge)\n", sdata->name); 666 667 ieee80211_request_internal_scan(sdata, 668 ifibss->ssid, ifibss->ssid_len, NULL); 669 } 670 671 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata) 672 { 673 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 674 u8 bssid[ETH_ALEN]; 675 u16 capability; 676 int i; 677 678 lockdep_assert_held(&ifibss->mtx); 679 680 if (ifibss->fixed_bssid) { 681 memcpy(bssid, ifibss->bssid, ETH_ALEN); 682 } else { 683 /* Generate random, not broadcast, locally administered BSSID. Mix in 684 * own MAC address to make sure that devices that do not have proper 685 * random number generator get different BSSID. */ 686 get_random_bytes(bssid, ETH_ALEN); 687 for (i = 0; i < ETH_ALEN; i++) 688 bssid[i] ^= sdata->vif.addr[i]; 689 bssid[0] &= ~0x01; 690 bssid[0] |= 0x02; 691 } 692 693 printk(KERN_DEBUG "%s: Creating new IBSS network, BSSID %pM\n", 694 sdata->name, bssid); 695 696 capability = WLAN_CAPABILITY_IBSS; 697 698 if (ifibss->privacy) 699 capability |= WLAN_CAPABILITY_PRIVACY; 700 else 701 sdata->drop_unencrypted = 0; 702 703 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int, 704 ifibss->channel, ifibss->basic_rates, 705 capability, 0); 706 } 707 708 /* 709 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH 710 */ 711 712 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata) 713 { 714 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 715 struct ieee80211_local *local = sdata->local; 716 struct cfg80211_bss *cbss; 717 struct ieee80211_channel *chan = NULL; 718 const u8 *bssid = NULL; 719 int active_ibss; 720 u16 capability; 721 722 lockdep_assert_held(&ifibss->mtx); 723 724 active_ibss = ieee80211_sta_active_ibss(sdata); 725 #ifdef CONFIG_MAC80211_IBSS_DEBUG 726 printk(KERN_DEBUG "%s: sta_find_ibss (active_ibss=%d)\n", 727 sdata->name, active_ibss); 728 #endif /* CONFIG_MAC80211_IBSS_DEBUG */ 729 730 if (active_ibss) 731 return; 732 733 capability = WLAN_CAPABILITY_IBSS; 734 if (ifibss->privacy) 735 capability |= WLAN_CAPABILITY_PRIVACY; 736 if (ifibss->fixed_bssid) 737 bssid = ifibss->bssid; 738 if (ifibss->fixed_channel) 739 chan = ifibss->channel; 740 if (!is_zero_ether_addr(ifibss->bssid)) 741 bssid = ifibss->bssid; 742 cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid, 743 ifibss->ssid, ifibss->ssid_len, 744 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY, 745 capability); 746 747 if (cbss) { 748 struct ieee80211_bss *bss; 749 750 bss = (void *)cbss->priv; 751 #ifdef CONFIG_MAC80211_IBSS_DEBUG 752 printk(KERN_DEBUG " sta_find_ibss: selected %pM current " 753 "%pM\n", cbss->bssid, ifibss->bssid); 754 #endif /* CONFIG_MAC80211_IBSS_DEBUG */ 755 756 printk(KERN_DEBUG "%s: Selected IBSS BSSID %pM" 757 " based on configured SSID\n", 758 sdata->name, cbss->bssid); 759 760 ieee80211_sta_join_ibss(sdata, bss); 761 ieee80211_rx_bss_put(local, bss); 762 return; 763 } 764 765 #ifdef CONFIG_MAC80211_IBSS_DEBUG 766 printk(KERN_DEBUG " did not try to join ibss\n"); 767 #endif /* CONFIG_MAC80211_IBSS_DEBUG */ 768 769 /* Selected IBSS not found in current scan results - try to scan */ 770 if (time_after(jiffies, ifibss->last_scan_completed + 771 IEEE80211_SCAN_INTERVAL)) { 772 printk(KERN_DEBUG "%s: Trigger new scan to find an IBSS to " 773 "join\n", sdata->name); 774 775 ieee80211_request_internal_scan(sdata, 776 ifibss->ssid, ifibss->ssid_len, 777 ifibss->fixed_channel ? ifibss->channel : NULL); 778 } else { 779 int interval = IEEE80211_SCAN_INTERVAL; 780 781 if (time_after(jiffies, ifibss->ibss_join_req + 782 IEEE80211_IBSS_JOIN_TIMEOUT)) { 783 if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) { 784 ieee80211_sta_create_ibss(sdata); 785 return; 786 } 787 printk(KERN_DEBUG "%s: IBSS not allowed on" 788 " %d MHz\n", sdata->name, 789 local->hw.conf.channel->center_freq); 790 791 /* No IBSS found - decrease scan interval and continue 792 * scanning. */ 793 interval = IEEE80211_SCAN_INTERVAL_SLOW; 794 } 795 796 mod_timer(&ifibss->timer, 797 round_jiffies(jiffies + interval)); 798 } 799 } 800 801 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata, 802 struct sk_buff *req) 803 { 804 struct ieee80211_mgmt *mgmt = (void *)req->data; 805 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 806 struct ieee80211_local *local = sdata->local; 807 int tx_last_beacon, len = req->len; 808 struct sk_buff *skb; 809 struct ieee80211_mgmt *resp; 810 struct sk_buff *presp; 811 u8 *pos, *end; 812 813 lockdep_assert_held(&ifibss->mtx); 814 815 presp = rcu_dereference_protected(ifibss->presp, 816 lockdep_is_held(&ifibss->mtx)); 817 818 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED || 819 len < 24 + 2 || !presp) 820 return; 821 822 tx_last_beacon = drv_tx_last_beacon(local); 823 824 #ifdef CONFIG_MAC80211_IBSS_DEBUG 825 printk(KERN_DEBUG "%s: RX ProbeReq SA=%pM DA=%pM BSSID=%pM" 826 " (tx_last_beacon=%d)\n", 827 sdata->name, mgmt->sa, mgmt->da, 828 mgmt->bssid, tx_last_beacon); 829 #endif /* CONFIG_MAC80211_IBSS_DEBUG */ 830 831 if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da)) 832 return; 833 834 if (compare_ether_addr(mgmt->bssid, ifibss->bssid) != 0 && 835 !is_broadcast_ether_addr(mgmt->bssid)) 836 return; 837 838 end = ((u8 *) mgmt) + len; 839 pos = mgmt->u.probe_req.variable; 840 if (pos[0] != WLAN_EID_SSID || 841 pos + 2 + pos[1] > end) { 842 #ifdef CONFIG_MAC80211_IBSS_DEBUG 843 printk(KERN_DEBUG "%s: Invalid SSID IE in ProbeReq " 844 "from %pM\n", 845 sdata->name, mgmt->sa); 846 #endif 847 return; 848 } 849 if (pos[1] != 0 && 850 (pos[1] != ifibss->ssid_len || 851 memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) { 852 /* Ignore ProbeReq for foreign SSID */ 853 return; 854 } 855 856 /* Reply with ProbeResp */ 857 skb = skb_copy(presp, GFP_KERNEL); 858 if (!skb) 859 return; 860 861 resp = (struct ieee80211_mgmt *) skb->data; 862 memcpy(resp->da, mgmt->sa, ETH_ALEN); 863 #ifdef CONFIG_MAC80211_IBSS_DEBUG 864 printk(KERN_DEBUG "%s: Sending ProbeResp to %pM\n", 865 sdata->name, resp->da); 866 #endif /* CONFIG_MAC80211_IBSS_DEBUG */ 867 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; 868 ieee80211_tx_skb(sdata, skb); 869 } 870 871 static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata, 872 struct ieee80211_mgmt *mgmt, 873 size_t len, 874 struct ieee80211_rx_status *rx_status) 875 { 876 size_t baselen; 877 struct ieee802_11_elems elems; 878 879 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt; 880 if (baselen > len) 881 return; 882 883 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen, 884 &elems); 885 886 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false); 887 } 888 889 static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 890 struct ieee80211_mgmt *mgmt, 891 size_t len, 892 struct ieee80211_rx_status *rx_status) 893 { 894 size_t baselen; 895 struct ieee802_11_elems elems; 896 897 /* Process beacon from the current BSS */ 898 baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt; 899 if (baselen > len) 900 return; 901 902 ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems); 903 904 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true); 905 } 906 907 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata, 908 struct sk_buff *skb) 909 { 910 struct ieee80211_rx_status *rx_status; 911 struct ieee80211_mgmt *mgmt; 912 u16 fc; 913 914 rx_status = IEEE80211_SKB_RXCB(skb); 915 mgmt = (struct ieee80211_mgmt *) skb->data; 916 fc = le16_to_cpu(mgmt->frame_control); 917 918 mutex_lock(&sdata->u.ibss.mtx); 919 920 if (!sdata->u.ibss.ssid_len) 921 goto mgmt_out; /* not ready to merge yet */ 922 923 switch (fc & IEEE80211_FCTL_STYPE) { 924 case IEEE80211_STYPE_PROBE_REQ: 925 ieee80211_rx_mgmt_probe_req(sdata, skb); 926 break; 927 case IEEE80211_STYPE_PROBE_RESP: 928 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len, 929 rx_status); 930 break; 931 case IEEE80211_STYPE_BEACON: 932 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len, 933 rx_status); 934 break; 935 case IEEE80211_STYPE_AUTH: 936 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len); 937 break; 938 } 939 940 mgmt_out: 941 mutex_unlock(&sdata->u.ibss.mtx); 942 } 943 944 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata) 945 { 946 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 947 struct sta_info *sta; 948 949 mutex_lock(&ifibss->mtx); 950 951 /* 952 * Work could be scheduled after scan or similar 953 * when we aren't even joined (or trying) with a 954 * network. 955 */ 956 if (!ifibss->ssid_len) 957 goto out; 958 959 spin_lock_bh(&ifibss->incomplete_lock); 960 while (!list_empty(&ifibss->incomplete_stations)) { 961 sta = list_first_entry(&ifibss->incomplete_stations, 962 struct sta_info, list); 963 list_del(&sta->list); 964 spin_unlock_bh(&ifibss->incomplete_lock); 965 966 ieee80211_ibss_finish_sta(sta, true); 967 rcu_read_unlock(); 968 spin_lock_bh(&ifibss->incomplete_lock); 969 } 970 spin_unlock_bh(&ifibss->incomplete_lock); 971 972 switch (ifibss->state) { 973 case IEEE80211_IBSS_MLME_SEARCH: 974 ieee80211_sta_find_ibss(sdata); 975 break; 976 case IEEE80211_IBSS_MLME_JOINED: 977 ieee80211_sta_merge_ibss(sdata); 978 break; 979 default: 980 WARN_ON(1); 981 break; 982 } 983 984 out: 985 mutex_unlock(&ifibss->mtx); 986 } 987 988 static void ieee80211_ibss_timer(unsigned long data) 989 { 990 struct ieee80211_sub_if_data *sdata = 991 (struct ieee80211_sub_if_data *) data; 992 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 993 struct ieee80211_local *local = sdata->local; 994 995 if (local->quiescing) { 996 ifibss->timer_running = true; 997 return; 998 } 999 1000 ieee80211_queue_work(&local->hw, &sdata->work); 1001 } 1002 1003 #ifdef CONFIG_PM 1004 void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata) 1005 { 1006 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1007 1008 if (del_timer_sync(&ifibss->timer)) 1009 ifibss->timer_running = true; 1010 } 1011 1012 void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata) 1013 { 1014 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1015 1016 if (ifibss->timer_running) { 1017 add_timer(&ifibss->timer); 1018 ifibss->timer_running = false; 1019 } 1020 } 1021 #endif 1022 1023 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata) 1024 { 1025 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1026 1027 setup_timer(&ifibss->timer, ieee80211_ibss_timer, 1028 (unsigned long) sdata); 1029 mutex_init(&ifibss->mtx); 1030 INIT_LIST_HEAD(&ifibss->incomplete_stations); 1031 spin_lock_init(&ifibss->incomplete_lock); 1032 } 1033 1034 /* scan finished notification */ 1035 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local) 1036 { 1037 struct ieee80211_sub_if_data *sdata; 1038 1039 mutex_lock(&local->iflist_mtx); 1040 list_for_each_entry(sdata, &local->interfaces, list) { 1041 if (!ieee80211_sdata_running(sdata)) 1042 continue; 1043 if (sdata->vif.type != NL80211_IFTYPE_ADHOC) 1044 continue; 1045 sdata->u.ibss.last_scan_completed = jiffies; 1046 ieee80211_queue_work(&local->hw, &sdata->work); 1047 } 1048 mutex_unlock(&local->iflist_mtx); 1049 } 1050 1051 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata, 1052 struct cfg80211_ibss_params *params) 1053 { 1054 struct sk_buff *skb; 1055 u32 changed = 0; 1056 1057 skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom + 1058 sizeof(struct ieee80211_hdr_3addr) + 1059 12 /* struct ieee80211_mgmt.u.beacon */ + 1060 2 + IEEE80211_MAX_SSID_LEN /* max SSID */ + 1061 2 + 8 /* max Supported Rates */ + 1062 3 /* max DS params */ + 1063 4 /* IBSS params */ + 1064 2 + (IEEE80211_MAX_SUPP_RATES - 8) + 1065 2 + sizeof(struct ieee80211_ht_cap) + 1066 2 + sizeof(struct ieee80211_ht_info) + 1067 params->ie_len); 1068 if (!skb) 1069 return -ENOMEM; 1070 1071 mutex_lock(&sdata->u.ibss.mtx); 1072 1073 if (params->bssid) { 1074 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN); 1075 sdata->u.ibss.fixed_bssid = true; 1076 } else 1077 sdata->u.ibss.fixed_bssid = false; 1078 1079 sdata->u.ibss.privacy = params->privacy; 1080 sdata->u.ibss.control_port = params->control_port; 1081 sdata->u.ibss.basic_rates = params->basic_rates; 1082 memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate, 1083 sizeof(params->mcast_rate)); 1084 1085 sdata->vif.bss_conf.beacon_int = params->beacon_interval; 1086 1087 sdata->u.ibss.channel = params->channel; 1088 sdata->u.ibss.channel_type = params->channel_type; 1089 sdata->u.ibss.fixed_channel = params->channel_fixed; 1090 1091 /* fix ourselves to that channel now already */ 1092 if (params->channel_fixed) { 1093 sdata->local->oper_channel = params->channel; 1094 if (!ieee80211_set_channel_type(sdata->local, sdata, 1095 params->channel_type)) { 1096 mutex_unlock(&sdata->u.ibss.mtx); 1097 kfree_skb(skb); 1098 return -EINVAL; 1099 } 1100 } 1101 1102 if (params->ie) { 1103 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len, 1104 GFP_KERNEL); 1105 if (sdata->u.ibss.ie) 1106 sdata->u.ibss.ie_len = params->ie_len; 1107 } 1108 1109 sdata->u.ibss.skb = skb; 1110 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; 1111 sdata->u.ibss.ibss_join_req = jiffies; 1112 1113 memcpy(sdata->u.ibss.ssid, params->ssid, IEEE80211_MAX_SSID_LEN); 1114 sdata->u.ibss.ssid_len = params->ssid_len; 1115 1116 mutex_unlock(&sdata->u.ibss.mtx); 1117 1118 mutex_lock(&sdata->local->mtx); 1119 ieee80211_recalc_idle(sdata->local); 1120 mutex_unlock(&sdata->local->mtx); 1121 1122 /* 1123 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is 1124 * reserved, but an HT STA shall protect HT transmissions as though 1125 * the HT Protection field were set to non-HT mixed mode. 1126 * 1127 * In an IBSS, the RIFS Mode field of the HT Operation element is 1128 * also reserved, but an HT STA shall operate as though this field 1129 * were set to 1. 1130 */ 1131 1132 sdata->vif.bss_conf.ht_operation_mode |= 1133 IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED 1134 | IEEE80211_HT_PARAM_RIFS_MODE; 1135 1136 changed |= BSS_CHANGED_HT; 1137 ieee80211_bss_info_change_notify(sdata, changed); 1138 1139 ieee80211_queue_work(&sdata->local->hw, &sdata->work); 1140 1141 return 0; 1142 } 1143 1144 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata) 1145 { 1146 struct sk_buff *skb; 1147 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 1148 struct ieee80211_local *local = sdata->local; 1149 struct cfg80211_bss *cbss; 1150 u16 capability; 1151 int active_ibss; 1152 struct sta_info *sta; 1153 1154 mutex_lock(&sdata->u.ibss.mtx); 1155 1156 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; 1157 memset(sdata->u.ibss.bssid, 0, ETH_ALEN); 1158 sdata->u.ibss.ssid_len = 0; 1159 1160 active_ibss = ieee80211_sta_active_ibss(sdata); 1161 1162 if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) { 1163 capability = WLAN_CAPABILITY_IBSS; 1164 1165 if (ifibss->privacy) 1166 capability |= WLAN_CAPABILITY_PRIVACY; 1167 1168 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel, 1169 ifibss->bssid, ifibss->ssid, 1170 ifibss->ssid_len, WLAN_CAPABILITY_IBSS | 1171 WLAN_CAPABILITY_PRIVACY, 1172 capability); 1173 1174 if (cbss) { 1175 cfg80211_unlink_bss(local->hw.wiphy, cbss); 1176 cfg80211_put_bss(cbss); 1177 } 1178 } 1179 1180 sta_info_flush(sdata->local, sdata); 1181 1182 spin_lock_bh(&ifibss->incomplete_lock); 1183 while (!list_empty(&ifibss->incomplete_stations)) { 1184 sta = list_first_entry(&ifibss->incomplete_stations, 1185 struct sta_info, list); 1186 list_del(&sta->list); 1187 spin_unlock_bh(&ifibss->incomplete_lock); 1188 1189 sta_info_free(local, sta); 1190 spin_lock_bh(&ifibss->incomplete_lock); 1191 } 1192 spin_unlock_bh(&ifibss->incomplete_lock); 1193 1194 netif_carrier_off(sdata->dev); 1195 1196 /* remove beacon */ 1197 kfree(sdata->u.ibss.ie); 1198 skb = rcu_dereference_protected(sdata->u.ibss.presp, 1199 lockdep_is_held(&sdata->u.ibss.mtx)); 1200 RCU_INIT_POINTER(sdata->u.ibss.presp, NULL); 1201 sdata->vif.bss_conf.ibss_joined = false; 1202 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED | 1203 BSS_CHANGED_IBSS); 1204 synchronize_rcu(); 1205 kfree_skb(skb); 1206 1207 skb_queue_purge(&sdata->skb_queue); 1208 1209 del_timer_sync(&sdata->u.ibss.timer); 1210 1211 mutex_unlock(&sdata->u.ibss.mtx); 1212 1213 mutex_lock(&local->mtx); 1214 ieee80211_recalc_idle(sdata->local); 1215 mutex_unlock(&local->mtx); 1216 1217 return 0; 1218 } 1219