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>
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.
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>
24 #include "ieee80211_i.h"
25 #include "driver-ops.h"
28 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
29 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
31 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
32 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
34 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
37 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
38 const u8 *bssid, const int beacon_int,
39 struct ieee80211_channel *chan,
40 const u32 basic_rates,
41 const u16 capability, u64 tsf,
44 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
45 struct ieee80211_local *local = sdata->local;
48 struct ieee80211_mgmt *mgmt;
50 struct ieee80211_supported_band *sband;
51 struct cfg80211_bss *bss;
53 u8 supp_rates[IEEE80211_MAX_SUPP_RATES];
54 struct cfg80211_chan_def chandef;
56 lockdep_assert_held(&ifibss->mtx);
58 /* Reset own TSF to allow time synchronization work. */
59 drv_reset_tsf(local, sdata);
62 RCU_INIT_POINTER(ifibss->presp, NULL);
64 skb->data = skb->head;
66 skb_reset_tail_pointer(skb);
67 skb_reserve(skb, sdata->local->hw.extra_tx_headroom);
69 if (!ether_addr_equal(ifibss->bssid, bssid))
70 sta_info_flush(sdata);
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 sdata->vif.bss_conf.ibss_creator = false;
76 netif_carrier_off(sdata->dev);
77 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IBSS);
80 sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
82 cfg80211_chandef_create(&chandef, chan, ifibss->channel_type);
83 if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) {
84 chandef.width = NL80211_CHAN_WIDTH_20;
85 chandef.center_freq1 = chan->center_freq;
88 ieee80211_vif_release_channel(sdata);
89 if (ieee80211_vif_use_channel(sdata, &chandef,
90 ifibss->fixed_channel ?
91 IEEE80211_CHANCTX_SHARED :
92 IEEE80211_CHANCTX_EXCLUSIVE)) {
93 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
97 memcpy(ifibss->bssid, bssid, ETH_ALEN);
99 sband = local->hw.wiphy->bands[chan->band];
101 /* build supported rates array */
103 for (i = 0; i < sband->n_bitrates; i++) {
104 int rate = sband->bitrates[i].bitrate;
106 if (basic_rates & BIT(i))
108 *pos++ = basic | (u8) (rate / 5);
111 /* Build IBSS probe response */
112 mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon));
113 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
114 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
115 IEEE80211_STYPE_PROBE_RESP);
116 eth_broadcast_addr(mgmt->da);
117 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
118 memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
119 mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
120 mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
121 mgmt->u.beacon.capab_info = cpu_to_le16(capability);
123 pos = skb_put(skb, 2 + ifibss->ssid_len);
124 *pos++ = WLAN_EID_SSID;
125 *pos++ = ifibss->ssid_len;
126 memcpy(pos, ifibss->ssid, ifibss->ssid_len);
128 rates = sband->n_bitrates;
131 pos = skb_put(skb, 2 + rates);
132 *pos++ = WLAN_EID_SUPP_RATES;
134 memcpy(pos, supp_rates, rates);
136 if (sband->band == IEEE80211_BAND_2GHZ) {
137 pos = skb_put(skb, 2 + 1);
138 *pos++ = WLAN_EID_DS_PARAMS;
140 *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
143 pos = skb_put(skb, 2 + 2);
144 *pos++ = WLAN_EID_IBSS_PARAMS;
146 /* FIX: set ATIM window based on scan results */
150 if (sband->n_bitrates > 8) {
151 rates = sband->n_bitrates - 8;
152 pos = skb_put(skb, 2 + rates);
153 *pos++ = WLAN_EID_EXT_SUPP_RATES;
155 memcpy(pos, &supp_rates[8], rates);
159 memcpy(skb_put(skb, ifibss->ie_len),
160 ifibss->ie, ifibss->ie_len);
162 /* add HT capability and information IEs */
163 if (chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
164 sband->ht_cap.ht_supported) {
165 pos = skb_put(skb, 4 +
166 sizeof(struct ieee80211_ht_cap) +
167 sizeof(struct ieee80211_ht_operation));
168 pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap,
171 * Note: According to 802.11n-2009 9.13.3.1, HT Protection
172 * field and RIFS Mode are reserved in IBSS mode, therefore
175 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
179 if (local->hw.queues >= IEEE80211_NUM_ACS) {
180 pos = skb_put(skb, 9);
181 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
182 *pos++ = 7; /* len */
183 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
186 *pos++ = 2; /* WME */
187 *pos++ = 0; /* WME info */
188 *pos++ = 1; /* WME ver */
189 *pos++ = 0; /* U-APSD no in use */
192 rcu_assign_pointer(ifibss->presp, skb);
194 sdata->vif.bss_conf.enable_beacon = true;
195 sdata->vif.bss_conf.beacon_int = beacon_int;
196 sdata->vif.bss_conf.basic_rates = basic_rates;
197 bss_change = BSS_CHANGED_BEACON_INT;
198 bss_change |= ieee80211_reset_erp_info(sdata);
199 bss_change |= BSS_CHANGED_BSSID;
200 bss_change |= BSS_CHANGED_BEACON;
201 bss_change |= BSS_CHANGED_BEACON_ENABLED;
202 bss_change |= BSS_CHANGED_BASIC_RATES;
203 bss_change |= BSS_CHANGED_HT;
204 bss_change |= BSS_CHANGED_IBSS;
207 * In 5 GHz/802.11a, we can always use short slot time.
208 * (IEEE 802.11-2012 18.3.8.7)
210 * In 2.4GHz, we must always use long slots in IBSS for compatibility
212 * (IEEE 802.11-2012 19.4.5)
214 * HT follows these specifications (IEEE 802.11-2012 20.3.18)
216 sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
217 bss_change |= BSS_CHANGED_ERP_SLOT;
219 sdata->vif.bss_conf.ibss_joined = true;
220 sdata->vif.bss_conf.ibss_creator = creator;
221 ieee80211_bss_info_change_notify(sdata, bss_change);
223 ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates);
225 ifibss->state = IEEE80211_IBSS_MLME_JOINED;
226 mod_timer(&ifibss->timer,
227 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
229 bss = cfg80211_inform_bss_frame(local->hw.wiphy, chan,
230 mgmt, skb->len, 0, GFP_KERNEL);
231 cfg80211_put_bss(local->hw.wiphy, bss);
232 netif_carrier_on(sdata->dev);
233 cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
236 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
237 struct ieee80211_bss *bss)
239 struct cfg80211_bss *cbss =
240 container_of((void *)bss, struct cfg80211_bss, priv);
241 struct ieee80211_supported_band *sband;
244 u16 beacon_int = cbss->beacon_interval;
246 lockdep_assert_held(&sdata->u.ibss.mtx);
251 sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
255 for (i = 0; i < bss->supp_rates_len; i++) {
256 int rate = (bss->supp_rates[i] & 0x7f) * 5;
257 bool is_basic = !!(bss->supp_rates[i] & 0x80);
259 for (j = 0; j < sband->n_bitrates; j++) {
260 if (sband->bitrates[j].bitrate == rate) {
262 basic_rates |= BIT(j);
268 __ieee80211_sta_join_ibss(sdata, cbss->bssid,
277 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta,
281 struct ieee80211_sub_if_data *sdata = sta->sdata;
284 memcpy(addr, sta->sta.addr, ETH_ALEN);
286 ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
288 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
289 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
290 /* authorize the station only if the network is not RSN protected. If
291 * not wait for the userspace to authorize it */
292 if (!sta->sdata->u.ibss.control_port)
293 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
295 rate_control_rate_init(sta);
297 /* If it fails, maybe we raced another insertion? */
298 if (sta_info_insert_rcu(sta))
299 return sta_info_get(sdata, addr);
300 if (auth && !sdata->u.ibss.auth_frame_registrations) {
302 "TX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=1)\n",
303 sdata->vif.addr, addr, sdata->u.ibss.bssid);
304 ieee80211_send_auth(sdata, 1, WLAN_AUTH_OPEN, 0, NULL, 0,
305 addr, sdata->u.ibss.bssid, NULL, 0, 0, 0);
310 static struct sta_info *
311 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
312 const u8 *bssid, const u8 *addr,
313 u32 supp_rates, bool auth)
316 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
317 struct ieee80211_local *local = sdata->local;
318 struct sta_info *sta;
319 struct ieee80211_chanctx_conf *chanctx_conf;
323 * XXX: Consider removing the least recently used entry and
324 * allow new one to be added.
326 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
327 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
333 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
338 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
344 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
345 if (WARN_ON_ONCE(!chanctx_conf))
347 band = chanctx_conf->def.chan->band;
350 sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
356 sta->last_rx = jiffies;
358 /* make sure mandatory rates are always added */
359 sta->sta.supp_rates[band] = supp_rates |
360 ieee80211_mandatory_rates(local, band);
362 return ieee80211_ibss_finish_sta(sta, auth);
365 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
366 struct ieee80211_mgmt *mgmt,
369 u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
371 if (len < IEEE80211_DEAUTH_FRAME_LEN)
374 ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
375 mgmt->sa, mgmt->da, mgmt->bssid, reason);
376 sta_info_destroy_addr(sdata, mgmt->sa);
379 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
380 struct ieee80211_mgmt *mgmt,
383 u16 auth_alg, auth_transaction;
384 struct sta_info *sta;
385 u8 deauth_frame_buf[IEEE80211_DEAUTH_FRAME_LEN];
387 lockdep_assert_held(&sdata->u.ibss.mtx);
392 auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
393 auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
396 "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
397 mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
399 if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
402 sta_info_destroy_addr(sdata, mgmt->sa);
403 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 0, false);
407 * if we have any problem in allocating the new station, we reply with a
408 * DEAUTH frame to tell the other end that we had a problem
411 ieee80211_send_deauth_disassoc(sdata, sdata->u.ibss.bssid,
412 IEEE80211_STYPE_DEAUTH,
413 WLAN_REASON_UNSPECIFIED, true,
419 * IEEE 802.11 standard does not require authentication in IBSS
420 * networks and most implementations do not seem to use it.
421 * However, try to reply to authentication attempts if someone
422 * has actually implemented this.
424 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
425 mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
428 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
429 struct ieee80211_mgmt *mgmt, size_t len,
430 struct ieee80211_rx_status *rx_status,
431 struct ieee802_11_elems *elems)
433 struct ieee80211_local *local = sdata->local;
435 struct cfg80211_bss *cbss;
436 struct ieee80211_bss *bss;
437 struct sta_info *sta;
438 struct ieee80211_channel *channel;
439 u64 beacon_timestamp, rx_timestamp;
441 enum ieee80211_band band = rx_status->band;
442 struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
443 bool rates_updated = false;
445 if (elems->ds_params && elems->ds_params_len == 1)
446 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
449 freq = rx_status->freq;
451 channel = ieee80211_get_channel(local->hw.wiphy, freq);
453 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
456 if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
457 ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
460 sta = sta_info_get(sdata, mgmt->sa);
462 if (elems->supp_rates) {
463 supp_rates = ieee80211_sta_get_rates(local, elems,
468 prev_rates = sta->sta.supp_rates[band];
469 /* make sure mandatory rates are always added */
470 sta->sta.supp_rates[band] = supp_rates |
471 ieee80211_mandatory_rates(local, band);
473 if (sta->sta.supp_rates[band] != prev_rates) {
475 "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
476 sta->sta.addr, prev_rates,
477 sta->sta.supp_rates[band]);
478 rates_updated = true;
482 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
483 mgmt->sa, supp_rates, true);
487 if (sta && elems->wmm_info)
488 set_sta_flag(sta, WLAN_STA_WME);
490 if (sta && elems->ht_operation && elems->ht_cap_elem &&
491 sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) {
493 struct ieee80211_sta_ht_cap sta_ht_cap_new;
494 struct cfg80211_chan_def chandef;
496 ieee80211_ht_oper_to_chandef(channel,
500 ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
505 * fall back to HT20 if we don't use or use
506 * the other extension channel
508 if (chandef.width != NL80211_CHAN_WIDTH_40 ||
509 cfg80211_get_chandef_type(&chandef) !=
510 sdata->u.ibss.channel_type)
511 sta_ht_cap_new.cap &=
512 ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
514 if (memcmp(&sta->sta.ht_cap, &sta_ht_cap_new,
515 sizeof(sta_ht_cap_new))) {
516 memcpy(&sta->sta.ht_cap, &sta_ht_cap_new,
517 sizeof(sta_ht_cap_new));
518 rates_updated = true;
522 if (sta && rates_updated) {
523 drv_sta_rc_update(local, sdata, &sta->sta,
524 IEEE80211_RC_SUPP_RATES_CHANGED);
525 rate_control_rate_init(sta);
531 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
536 cbss = container_of((void *)bss, struct cfg80211_bss, priv);
538 /* was just updated in ieee80211_bss_info_update */
539 beacon_timestamp = cbss->tsf;
541 /* check if we need to merge IBSS */
543 /* we use a fixed BSSID */
544 if (sdata->u.ibss.fixed_bssid)
548 if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
551 /* different channel */
552 if (sdata->u.ibss.fixed_channel &&
553 sdata->u.ibss.channel != cbss->channel)
557 if (elems->ssid_len != sdata->u.ibss.ssid_len ||
558 memcmp(elems->ssid, sdata->u.ibss.ssid,
559 sdata->u.ibss.ssid_len))
563 if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
566 if (ieee80211_have_rx_timestamp(rx_status)) {
567 /* time when timestamp field was received */
569 ieee80211_calculate_rx_timestamp(local, rx_status,
573 * second best option: get current TSF
574 * (will return -1 if not supported)
576 rx_timestamp = drv_get_tsf(local, sdata);
580 "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
581 mgmt->sa, mgmt->bssid,
582 (unsigned long long)rx_timestamp,
583 (unsigned long long)beacon_timestamp,
584 (unsigned long long)(rx_timestamp - beacon_timestamp),
587 if (beacon_timestamp > rx_timestamp) {
589 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
591 ieee80211_sta_join_ibss(sdata, bss);
592 supp_rates = ieee80211_sta_get_rates(local, elems, band, NULL);
593 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
599 ieee80211_rx_bss_put(local, bss);
602 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
603 const u8 *bssid, const u8 *addr,
606 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
607 struct ieee80211_local *local = sdata->local;
608 struct sta_info *sta;
609 struct ieee80211_chanctx_conf *chanctx_conf;
613 * XXX: Consider removing the least recently used entry and
614 * allow new one to be added.
616 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
617 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
622 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
625 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
629 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
630 if (WARN_ON_ONCE(!chanctx_conf)) {
634 band = chanctx_conf->def.chan->band;
637 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
641 sta->last_rx = jiffies;
643 /* make sure mandatory rates are always added */
644 sta->sta.supp_rates[band] = supp_rates |
645 ieee80211_mandatory_rates(local, band);
647 spin_lock(&ifibss->incomplete_lock);
648 list_add(&sta->list, &ifibss->incomplete_stations);
649 spin_unlock(&ifibss->incomplete_lock);
650 ieee80211_queue_work(&local->hw, &sdata->work);
653 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
655 struct ieee80211_local *local = sdata->local;
657 struct sta_info *sta;
659 lockdep_assert_held(&sdata->u.ibss.mtx);
663 list_for_each_entry_rcu(sta, &local->sta_list, list) {
664 if (sta->sdata == sdata &&
665 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
678 * This function is called with state == IEEE80211_IBSS_MLME_JOINED
681 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
683 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
685 lockdep_assert_held(&ifibss->mtx);
687 mod_timer(&ifibss->timer,
688 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
690 ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
692 if (time_before(jiffies, ifibss->last_scan_completed +
693 IEEE80211_IBSS_MERGE_INTERVAL))
696 if (ieee80211_sta_active_ibss(sdata))
699 if (ifibss->fixed_channel)
703 "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
705 ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
709 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
711 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
716 lockdep_assert_held(&ifibss->mtx);
718 if (ifibss->fixed_bssid) {
719 memcpy(bssid, ifibss->bssid, ETH_ALEN);
721 /* Generate random, not broadcast, locally administered BSSID. Mix in
722 * own MAC address to make sure that devices that do not have proper
723 * random number generator get different BSSID. */
724 get_random_bytes(bssid, ETH_ALEN);
725 for (i = 0; i < ETH_ALEN; i++)
726 bssid[i] ^= sdata->vif.addr[i];
731 sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
733 capability = WLAN_CAPABILITY_IBSS;
736 capability |= WLAN_CAPABILITY_PRIVACY;
738 sdata->drop_unencrypted = 0;
740 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
741 ifibss->channel, ifibss->basic_rates,
742 capability, 0, true);
746 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
749 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
751 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
752 struct ieee80211_local *local = sdata->local;
753 struct cfg80211_bss *cbss;
754 struct ieee80211_channel *chan = NULL;
755 const u8 *bssid = NULL;
759 lockdep_assert_held(&ifibss->mtx);
761 active_ibss = ieee80211_sta_active_ibss(sdata);
762 ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
767 capability = WLAN_CAPABILITY_IBSS;
769 capability |= WLAN_CAPABILITY_PRIVACY;
770 if (ifibss->fixed_bssid)
771 bssid = ifibss->bssid;
772 if (ifibss->fixed_channel)
773 chan = ifibss->channel;
774 if (!is_zero_ether_addr(ifibss->bssid))
775 bssid = ifibss->bssid;
776 cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
777 ifibss->ssid, ifibss->ssid_len,
778 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
782 struct ieee80211_bss *bss;
784 bss = (void *)cbss->priv;
786 "sta_find_ibss: selected %pM current %pM\n",
787 cbss->bssid, ifibss->bssid);
789 "Selected IBSS BSSID %pM based on configured SSID\n",
792 ieee80211_sta_join_ibss(sdata, bss);
793 ieee80211_rx_bss_put(local, bss);
797 ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
799 /* Selected IBSS not found in current scan results - try to scan */
800 if (time_after(jiffies, ifibss->last_scan_completed +
801 IEEE80211_SCAN_INTERVAL)) {
802 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
804 ieee80211_request_ibss_scan(sdata, ifibss->ssid,
805 ifibss->ssid_len, chan);
807 int interval = IEEE80211_SCAN_INTERVAL;
809 if (time_after(jiffies, ifibss->ibss_join_req +
810 IEEE80211_IBSS_JOIN_TIMEOUT))
811 ieee80211_sta_create_ibss(sdata);
813 mod_timer(&ifibss->timer,
814 round_jiffies(jiffies + interval));
818 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
821 struct ieee80211_mgmt *mgmt = (void *)req->data;
822 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
823 struct ieee80211_local *local = sdata->local;
824 int tx_last_beacon, len = req->len;
826 struct ieee80211_mgmt *resp;
827 struct sk_buff *presp;
830 lockdep_assert_held(&ifibss->mtx);
832 presp = rcu_dereference_protected(ifibss->presp,
833 lockdep_is_held(&ifibss->mtx));
835 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
836 len < 24 + 2 || !presp)
839 tx_last_beacon = drv_tx_last_beacon(local);
842 "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
843 mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
845 if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
848 if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
849 !is_broadcast_ether_addr(mgmt->bssid))
852 end = ((u8 *) mgmt) + len;
853 pos = mgmt->u.probe_req.variable;
854 if (pos[0] != WLAN_EID_SSID ||
855 pos + 2 + pos[1] > end) {
856 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
861 (pos[1] != ifibss->ssid_len ||
862 memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
863 /* Ignore ProbeReq for foreign SSID */
867 /* Reply with ProbeResp */
868 skb = skb_copy(presp, GFP_KERNEL);
872 resp = (struct ieee80211_mgmt *) skb->data;
873 memcpy(resp->da, mgmt->sa, ETH_ALEN);
874 ibss_dbg(sdata, "Sending ProbeResp to %pM\n", resp->da);
875 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
876 ieee80211_tx_skb(sdata, skb);
880 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
881 struct ieee80211_mgmt *mgmt, size_t len,
882 struct ieee80211_rx_status *rx_status)
885 struct ieee802_11_elems elems;
887 BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
888 offsetof(typeof(mgmt->u.beacon), variable));
891 * either beacon or probe_resp but the variable field is at the
894 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
898 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
901 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
904 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
907 struct ieee80211_rx_status *rx_status;
908 struct ieee80211_mgmt *mgmt;
911 rx_status = IEEE80211_SKB_RXCB(skb);
912 mgmt = (struct ieee80211_mgmt *) skb->data;
913 fc = le16_to_cpu(mgmt->frame_control);
915 mutex_lock(&sdata->u.ibss.mtx);
917 if (!sdata->u.ibss.ssid_len)
918 goto mgmt_out; /* not ready to merge yet */
920 switch (fc & IEEE80211_FCTL_STYPE) {
921 case IEEE80211_STYPE_PROBE_REQ:
922 ieee80211_rx_mgmt_probe_req(sdata, skb);
924 case IEEE80211_STYPE_PROBE_RESP:
925 case IEEE80211_STYPE_BEACON:
926 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
929 case IEEE80211_STYPE_AUTH:
930 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
932 case IEEE80211_STYPE_DEAUTH:
933 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
938 mutex_unlock(&sdata->u.ibss.mtx);
941 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
943 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
944 struct sta_info *sta;
946 mutex_lock(&ifibss->mtx);
949 * Work could be scheduled after scan or similar
950 * when we aren't even joined (or trying) with a
953 if (!ifibss->ssid_len)
956 spin_lock_bh(&ifibss->incomplete_lock);
957 while (!list_empty(&ifibss->incomplete_stations)) {
958 sta = list_first_entry(&ifibss->incomplete_stations,
959 struct sta_info, list);
960 list_del(&sta->list);
961 spin_unlock_bh(&ifibss->incomplete_lock);
963 ieee80211_ibss_finish_sta(sta, true);
965 spin_lock_bh(&ifibss->incomplete_lock);
967 spin_unlock_bh(&ifibss->incomplete_lock);
969 switch (ifibss->state) {
970 case IEEE80211_IBSS_MLME_SEARCH:
971 ieee80211_sta_find_ibss(sdata);
973 case IEEE80211_IBSS_MLME_JOINED:
974 ieee80211_sta_merge_ibss(sdata);
982 mutex_unlock(&ifibss->mtx);
985 static void ieee80211_ibss_timer(unsigned long data)
987 struct ieee80211_sub_if_data *sdata =
988 (struct ieee80211_sub_if_data *) data;
989 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
990 struct ieee80211_local *local = sdata->local;
992 if (local->quiescing) {
993 ifibss->timer_running = true;
997 ieee80211_queue_work(&local->hw, &sdata->work);
1001 void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata)
1003 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1005 if (del_timer_sync(&ifibss->timer))
1006 ifibss->timer_running = true;
1009 void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata)
1011 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1013 if (ifibss->timer_running) {
1014 add_timer(&ifibss->timer);
1015 ifibss->timer_running = false;
1020 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1022 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1024 setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1025 (unsigned long) sdata);
1026 mutex_init(&ifibss->mtx);
1027 INIT_LIST_HEAD(&ifibss->incomplete_stations);
1028 spin_lock_init(&ifibss->incomplete_lock);
1031 /* scan finished notification */
1032 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1034 struct ieee80211_sub_if_data *sdata;
1036 mutex_lock(&local->iflist_mtx);
1037 list_for_each_entry(sdata, &local->interfaces, list) {
1038 if (!ieee80211_sdata_running(sdata))
1040 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1042 sdata->u.ibss.last_scan_completed = jiffies;
1043 ieee80211_queue_work(&local->hw, &sdata->work);
1045 mutex_unlock(&local->iflist_mtx);
1048 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1049 struct cfg80211_ibss_params *params)
1051 struct sk_buff *skb;
1054 skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
1055 sizeof(struct ieee80211_hdr_3addr) +
1056 12 /* struct ieee80211_mgmt.u.beacon */ +
1057 2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
1058 2 + 8 /* max Supported Rates */ +
1059 3 /* max DS params */ +
1060 4 /* IBSS params */ +
1061 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
1062 2 + sizeof(struct ieee80211_ht_cap) +
1063 2 + sizeof(struct ieee80211_ht_operation) +
1068 mutex_lock(&sdata->u.ibss.mtx);
1070 if (params->bssid) {
1071 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1072 sdata->u.ibss.fixed_bssid = true;
1074 sdata->u.ibss.fixed_bssid = false;
1076 sdata->u.ibss.privacy = params->privacy;
1077 sdata->u.ibss.control_port = params->control_port;
1078 sdata->u.ibss.basic_rates = params->basic_rates;
1079 memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1080 sizeof(params->mcast_rate));
1082 sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1084 sdata->u.ibss.channel = params->chandef.chan;
1085 sdata->u.ibss.channel_type =
1086 cfg80211_get_chandef_type(¶ms->chandef);
1087 sdata->u.ibss.fixed_channel = params->channel_fixed;
1090 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1092 if (sdata->u.ibss.ie)
1093 sdata->u.ibss.ie_len = params->ie_len;
1096 sdata->u.ibss.skb = skb;
1097 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1098 sdata->u.ibss.ibss_join_req = jiffies;
1100 memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1101 sdata->u.ibss.ssid_len = params->ssid_len;
1103 mutex_unlock(&sdata->u.ibss.mtx);
1105 mutex_lock(&sdata->local->mtx);
1106 ieee80211_recalc_idle(sdata->local);
1107 mutex_unlock(&sdata->local->mtx);
1110 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1111 * reserved, but an HT STA shall protect HT transmissions as though
1112 * the HT Protection field were set to non-HT mixed mode.
1114 * In an IBSS, the RIFS Mode field of the HT Operation element is
1115 * also reserved, but an HT STA shall operate as though this field
1119 sdata->vif.bss_conf.ht_operation_mode |=
1120 IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1121 | IEEE80211_HT_PARAM_RIFS_MODE;
1123 changed |= BSS_CHANGED_HT;
1124 ieee80211_bss_info_change_notify(sdata, changed);
1126 sdata->smps_mode = IEEE80211_SMPS_OFF;
1127 sdata->needed_rx_chains = sdata->local->rx_chains;
1129 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1134 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1136 struct sk_buff *skb;
1137 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1138 struct ieee80211_local *local = sdata->local;
1139 struct cfg80211_bss *cbss;
1142 struct sta_info *sta;
1144 mutex_lock(&sdata->u.ibss.mtx);
1146 active_ibss = ieee80211_sta_active_ibss(sdata);
1148 if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
1149 capability = WLAN_CAPABILITY_IBSS;
1151 if (ifibss->privacy)
1152 capability |= WLAN_CAPABILITY_PRIVACY;
1154 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel,
1155 ifibss->bssid, ifibss->ssid,
1156 ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
1157 WLAN_CAPABILITY_PRIVACY,
1161 cfg80211_unlink_bss(local->hw.wiphy, cbss);
1162 cfg80211_put_bss(local->hw.wiphy, cbss);
1166 ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
1167 memset(ifibss->bssid, 0, ETH_ALEN);
1168 ifibss->ssid_len = 0;
1170 sta_info_flush(sdata);
1172 spin_lock_bh(&ifibss->incomplete_lock);
1173 while (!list_empty(&ifibss->incomplete_stations)) {
1174 sta = list_first_entry(&ifibss->incomplete_stations,
1175 struct sta_info, list);
1176 list_del(&sta->list);
1177 spin_unlock_bh(&ifibss->incomplete_lock);
1179 sta_info_free(local, sta);
1180 spin_lock_bh(&ifibss->incomplete_lock);
1182 spin_unlock_bh(&ifibss->incomplete_lock);
1184 netif_carrier_off(sdata->dev);
1187 kfree(sdata->u.ibss.ie);
1188 skb = rcu_dereference_protected(sdata->u.ibss.presp,
1189 lockdep_is_held(&sdata->u.ibss.mtx));
1190 RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
1191 sdata->vif.bss_conf.ibss_joined = false;
1192 sdata->vif.bss_conf.ibss_creator = false;
1193 sdata->vif.bss_conf.enable_beacon = false;
1194 clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
1195 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
1200 skb_queue_purge(&sdata->skb_queue);
1202 del_timer_sync(&sdata->u.ibss.timer);
1204 mutex_unlock(&sdata->u.ibss.mtx);
1206 mutex_lock(&local->mtx);
1207 ieee80211_recalc_idle(sdata->local);
1208 mutex_unlock(&local->mtx);