ibss.c revision 2ec9c1f67ab1f58b5bf5ac19e4b61b9f75c83a04
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_IBSS_JOIN_TIMEOUT (7 * HZ)
30
31#define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
32#define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
33
34#define IEEE80211_IBSS_MAX_STA_ENTRIES 128
35
36
37static 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,
42				      bool creator)
43{
44	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
45	struct ieee80211_local *local = sdata->local;
46	int rates_n = 0, i, ri;
47	struct ieee80211_mgmt *mgmt;
48	u8 *pos;
49	struct ieee80211_supported_band *sband;
50	struct cfg80211_bss *bss;
51	u32 bss_change, rate_flags, rates = 0, rates_added = 0;
52	struct cfg80211_chan_def chandef;
53	enum nl80211_bss_scan_width scan_width;
54	bool have_higher_than_11mbit = false;
55	struct beacon_data *presp;
56	int frame_len;
57	int shift;
58
59	sdata_assert_lock(sdata);
60
61	/* Reset own TSF to allow time synchronization work. */
62	drv_reset_tsf(local, sdata);
63
64	if (!ether_addr_equal(ifibss->bssid, bssid))
65		sta_info_flush(sdata);
66
67	/* if merging, indicate to driver that we leave the old IBSS */
68	if (sdata->vif.bss_conf.ibss_joined) {
69		sdata->vif.bss_conf.ibss_joined = false;
70		sdata->vif.bss_conf.ibss_creator = false;
71		sdata->vif.bss_conf.enable_beacon = false;
72		netif_carrier_off(sdata->dev);
73		ieee80211_bss_info_change_notify(sdata,
74						 BSS_CHANGED_IBSS |
75						 BSS_CHANGED_BEACON_ENABLED);
76	}
77
78	presp = rcu_dereference_protected(ifibss->presp,
79					  lockdep_is_held(&sdata->wdev.mtx));
80	rcu_assign_pointer(ifibss->presp, NULL);
81	if (presp)
82		kfree_rcu(presp, rcu_head);
83
84	sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
85
86	chandef = ifibss->chandef;
87	if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) {
88		if (chandef.width == NL80211_CHAN_WIDTH_5 ||
89		    chandef.width == NL80211_CHAN_WIDTH_10 ||
90		    chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
91		    chandef.width == NL80211_CHAN_WIDTH_20) {
92			sdata_info(sdata,
93				   "Failed to join IBSS, beacons forbidden\n");
94			return;
95		}
96		chandef.width = NL80211_CHAN_WIDTH_20;
97		chandef.center_freq1 = chan->center_freq;
98	}
99
100	ieee80211_vif_release_channel(sdata);
101	if (ieee80211_vif_use_channel(sdata, &chandef,
102				      ifibss->fixed_channel ?
103					IEEE80211_CHANCTX_SHARED :
104					IEEE80211_CHANCTX_EXCLUSIVE)) {
105		sdata_info(sdata, "Failed to join IBSS, no channel context\n");
106		return;
107	}
108
109	memcpy(ifibss->bssid, bssid, ETH_ALEN);
110
111	sband = local->hw.wiphy->bands[chan->band];
112	shift = ieee80211_vif_get_shift(&sdata->vif);
113
114	/* Build IBSS probe response */
115	frame_len = sizeof(struct ieee80211_hdr_3addr) +
116		    12 /* struct ieee80211_mgmt.u.beacon */ +
117		    2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
118		    2 + 8 /* max Supported Rates */ +
119		    3 /* max DS params */ +
120		    4 /* IBSS params */ +
121		    2 + (IEEE80211_MAX_SUPP_RATES - 8) +
122		    2 + sizeof(struct ieee80211_ht_cap) +
123		    2 + sizeof(struct ieee80211_ht_operation) +
124		    ifibss->ie_len;
125	presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
126	if (!presp)
127		return;
128
129	presp->head = (void *)(presp + 1);
130
131	mgmt = (void *) presp->head;
132	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
133					  IEEE80211_STYPE_PROBE_RESP);
134	eth_broadcast_addr(mgmt->da);
135	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
136	memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
137	mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
138	mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
139	mgmt->u.beacon.capab_info = cpu_to_le16(capability);
140
141	pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
142
143	*pos++ = WLAN_EID_SSID;
144	*pos++ = ifibss->ssid_len;
145	memcpy(pos, ifibss->ssid, ifibss->ssid_len);
146	pos += ifibss->ssid_len;
147
148	rate_flags = ieee80211_chandef_rate_flags(&chandef);
149	for (i = 0; i < sband->n_bitrates; i++) {
150		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
151			continue;
152		if (sband->bitrates[i].bitrate > 110)
153			have_higher_than_11mbit = true;
154
155		rates |= BIT(i);
156		rates_n++;
157	}
158
159	*pos++ = WLAN_EID_SUPP_RATES;
160	*pos++ = min_t(int, 8, rates_n);
161	for (ri = 0; ri < sband->n_bitrates; ri++) {
162		int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
163					5 * (1 << shift));
164		u8 basic = 0;
165		if (!(rates & BIT(ri)))
166			continue;
167
168		if (basic_rates & BIT(ri))
169			basic = 0x80;
170		*pos++ = basic | (u8) rate;
171		if (++rates_added == 8)
172			break;
173	}
174
175	if (sband->band == IEEE80211_BAND_2GHZ) {
176		*pos++ = WLAN_EID_DS_PARAMS;
177		*pos++ = 1;
178		*pos++ = ieee80211_frequency_to_channel(chan->center_freq);
179	}
180
181	*pos++ = WLAN_EID_IBSS_PARAMS;
182	*pos++ = 2;
183	/* FIX: set ATIM window based on scan results */
184	*pos++ = 0;
185	*pos++ = 0;
186
187	/* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
188	if (rates_n > 8) {
189		*pos++ = WLAN_EID_EXT_SUPP_RATES;
190		*pos++ = rates_n - 8;
191		for (; ri < sband->n_bitrates; ri++) {
192			int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
193						5 * (1 << shift));
194			u8 basic = 0;
195			if (!(rates & BIT(ri)))
196				continue;
197
198			if (basic_rates & BIT(ri))
199				basic = 0x80;
200			*pos++ = basic | (u8) rate;
201		}
202	}
203
204	if (ifibss->ie_len) {
205		memcpy(pos, ifibss->ie, ifibss->ie_len);
206		pos += ifibss->ie_len;
207	}
208
209	/* add HT capability and information IEs */
210	if (chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
211	    chandef.width != NL80211_CHAN_WIDTH_5 &&
212	    chandef.width != NL80211_CHAN_WIDTH_10 &&
213	    sband->ht_cap.ht_supported) {
214		struct ieee80211_sta_ht_cap ht_cap;
215
216		memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
217		ieee80211_apply_htcap_overrides(sdata, &ht_cap);
218
219		pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
220		/*
221		 * Note: According to 802.11n-2009 9.13.3.1, HT Protection
222		 * field and RIFS Mode are reserved in IBSS mode, therefore
223		 * keep them at 0
224		 */
225		pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
226						 &chandef, 0);
227	}
228
229	if (local->hw.queues >= IEEE80211_NUM_ACS) {
230		*pos++ = WLAN_EID_VENDOR_SPECIFIC;
231		*pos++ = 7; /* len */
232		*pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
233		*pos++ = 0x50;
234		*pos++ = 0xf2;
235		*pos++ = 2; /* WME */
236		*pos++ = 0; /* WME info */
237		*pos++ = 1; /* WME ver */
238		*pos++ = 0; /* U-APSD no in use */
239	}
240
241	presp->head_len = pos - presp->head;
242	if (WARN_ON(presp->head_len > frame_len))
243		return;
244
245	rcu_assign_pointer(ifibss->presp, presp);
246
247	sdata->vif.bss_conf.enable_beacon = true;
248	sdata->vif.bss_conf.beacon_int = beacon_int;
249	sdata->vif.bss_conf.basic_rates = basic_rates;
250	sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
251	memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
252	bss_change = BSS_CHANGED_BEACON_INT;
253	bss_change |= ieee80211_reset_erp_info(sdata);
254	bss_change |= BSS_CHANGED_BSSID;
255	bss_change |= BSS_CHANGED_BEACON;
256	bss_change |= BSS_CHANGED_BEACON_ENABLED;
257	bss_change |= BSS_CHANGED_BASIC_RATES;
258	bss_change |= BSS_CHANGED_HT;
259	bss_change |= BSS_CHANGED_IBSS;
260	bss_change |= BSS_CHANGED_SSID;
261
262	/*
263	 * In 5 GHz/802.11a, we can always use short slot time.
264	 * (IEEE 802.11-2012 18.3.8.7)
265	 *
266	 * In 2.4GHz, we must always use long slots in IBSS for compatibility
267	 * reasons.
268	 * (IEEE 802.11-2012 19.4.5)
269	 *
270	 * HT follows these specifications (IEEE 802.11-2012 20.3.18)
271	 */
272	sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
273	bss_change |= BSS_CHANGED_ERP_SLOT;
274
275	/* cf. IEEE 802.11 9.2.12 */
276	if (chan->band == IEEE80211_BAND_2GHZ && have_higher_than_11mbit)
277		sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
278	else
279		sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
280
281	sdata->vif.bss_conf.ibss_joined = true;
282	sdata->vif.bss_conf.ibss_creator = creator;
283	ieee80211_bss_info_change_notify(sdata, bss_change);
284
285	ieee80211_set_wmm_default(sdata, true);
286
287	ifibss->state = IEEE80211_IBSS_MLME_JOINED;
288	mod_timer(&ifibss->timer,
289		  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
290
291	scan_width = cfg80211_chandef_to_scan_width(&chandef);
292	bss = cfg80211_inform_bss_width_frame(local->hw.wiphy, chan,
293					      scan_width, mgmt,
294					      presp->head_len, 0, GFP_KERNEL);
295	cfg80211_put_bss(local->hw.wiphy, bss);
296	netif_carrier_on(sdata->dev);
297	cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
298}
299
300static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
301				    struct ieee80211_bss *bss)
302{
303	struct cfg80211_bss *cbss =
304		container_of((void *)bss, struct cfg80211_bss, priv);
305	struct ieee80211_supported_band *sband;
306	u32 basic_rates;
307	int i, j;
308	u16 beacon_int = cbss->beacon_interval;
309	const struct cfg80211_bss_ies *ies;
310	u64 tsf;
311	u32 rate_flags;
312	int shift;
313
314	sdata_assert_lock(sdata);
315
316	if (beacon_int < 10)
317		beacon_int = 10;
318
319	sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
320	rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
321	shift = ieee80211_vif_get_shift(&sdata->vif);
322
323	basic_rates = 0;
324
325	for (i = 0; i < bss->supp_rates_len; i++) {
326		int rate = bss->supp_rates[i] & 0x7f;
327		bool is_basic = !!(bss->supp_rates[i] & 0x80);
328
329		for (j = 0; j < sband->n_bitrates; j++) {
330			int brate;
331			if ((rate_flags & sband->bitrates[j].flags)
332			    != rate_flags)
333				continue;
334
335			brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
336					     5 * (1 << shift));
337			if (brate == rate) {
338				if (is_basic)
339					basic_rates |= BIT(j);
340				break;
341			}
342		}
343	}
344
345	rcu_read_lock();
346	ies = rcu_dereference(cbss->ies);
347	tsf = ies->tsf;
348	rcu_read_unlock();
349
350	__ieee80211_sta_join_ibss(sdata, cbss->bssid,
351				  beacon_int,
352				  cbss->channel,
353				  basic_rates,
354				  cbss->capability,
355				  tsf, false);
356}
357
358static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
359	__acquires(RCU)
360{
361	struct ieee80211_sub_if_data *sdata = sta->sdata;
362	u8 addr[ETH_ALEN];
363
364	memcpy(addr, sta->sta.addr, ETH_ALEN);
365
366	ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
367
368	sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
369	sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
370	/* authorize the station only if the network is not RSN protected. If
371	 * not wait for the userspace to authorize it */
372	if (!sta->sdata->u.ibss.control_port)
373		sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
374
375	rate_control_rate_init(sta);
376
377	/* If it fails, maybe we raced another insertion? */
378	if (sta_info_insert_rcu(sta))
379		return sta_info_get(sdata, addr);
380	return sta;
381}
382
383static struct sta_info *
384ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
385		       const u8 *addr, u32 supp_rates)
386	__acquires(RCU)
387{
388	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
389	struct ieee80211_local *local = sdata->local;
390	struct sta_info *sta;
391	struct ieee80211_chanctx_conf *chanctx_conf;
392	struct ieee80211_supported_band *sband;
393	enum nl80211_bss_scan_width scan_width;
394	int band;
395
396	/*
397	 * XXX: Consider removing the least recently used entry and
398	 * 	allow new one to be added.
399	 */
400	if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
401		net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
402				    sdata->name, addr);
403		rcu_read_lock();
404		return NULL;
405	}
406
407	if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
408		rcu_read_lock();
409		return NULL;
410	}
411
412	if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
413		rcu_read_lock();
414		return NULL;
415	}
416
417	rcu_read_lock();
418	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
419	if (WARN_ON_ONCE(!chanctx_conf))
420		return NULL;
421	band = chanctx_conf->def.chan->band;
422	scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
423	rcu_read_unlock();
424
425	sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
426	if (!sta) {
427		rcu_read_lock();
428		return NULL;
429	}
430
431	sta->last_rx = jiffies;
432
433	/* make sure mandatory rates are always added */
434	sband = local->hw.wiphy->bands[band];
435	sta->sta.supp_rates[band] = supp_rates |
436			ieee80211_mandatory_rates(sband, scan_width);
437
438	return ieee80211_ibss_finish_sta(sta);
439}
440
441static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
442					  struct ieee80211_mgmt *mgmt,
443					  size_t len)
444{
445	u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
446
447	if (len < IEEE80211_DEAUTH_FRAME_LEN)
448		return;
449
450	ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
451		 mgmt->sa, mgmt->da, mgmt->bssid, reason);
452	sta_info_destroy_addr(sdata, mgmt->sa);
453}
454
455static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
456					struct ieee80211_mgmt *mgmt,
457					size_t len)
458{
459	u16 auth_alg, auth_transaction;
460
461	sdata_assert_lock(sdata);
462
463	if (len < 24 + 6)
464		return;
465
466	auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
467	auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
468
469	ibss_dbg(sdata,
470		 "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
471		 mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
472
473	if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
474		return;
475
476	/*
477	 * IEEE 802.11 standard does not require authentication in IBSS
478	 * networks and most implementations do not seem to use it.
479	 * However, try to reply to authentication attempts if someone
480	 * has actually implemented this.
481	 */
482	ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
483			    mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
484}
485
486static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
487				  struct ieee80211_mgmt *mgmt, size_t len,
488				  struct ieee80211_rx_status *rx_status,
489				  struct ieee802_11_elems *elems)
490{
491	struct ieee80211_local *local = sdata->local;
492	int freq;
493	struct cfg80211_bss *cbss;
494	struct ieee80211_bss *bss;
495	struct sta_info *sta;
496	struct ieee80211_channel *channel;
497	u64 beacon_timestamp, rx_timestamp;
498	u32 supp_rates = 0;
499	enum ieee80211_band band = rx_status->band;
500	enum nl80211_bss_scan_width scan_width;
501	struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
502	bool rates_updated = false;
503
504	if (elems->ds_params)
505		freq = ieee80211_channel_to_frequency(elems->ds_params[0],
506						      band);
507	else
508		freq = rx_status->freq;
509
510	channel = ieee80211_get_channel(local->hw.wiphy, freq);
511
512	if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
513		return;
514
515	if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
516	    ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
517
518		rcu_read_lock();
519		sta = sta_info_get(sdata, mgmt->sa);
520
521		if (elems->supp_rates) {
522			supp_rates = ieee80211_sta_get_rates(sdata, elems,
523							     band, NULL);
524			if (sta) {
525				u32 prev_rates;
526
527				prev_rates = sta->sta.supp_rates[band];
528				/* make sure mandatory rates are always added */
529				scan_width = NL80211_BSS_CHAN_WIDTH_20;
530				if (rx_status->flag & RX_FLAG_5MHZ)
531					scan_width = NL80211_BSS_CHAN_WIDTH_5;
532				if (rx_status->flag & RX_FLAG_10MHZ)
533					scan_width = NL80211_BSS_CHAN_WIDTH_10;
534
535				sta->sta.supp_rates[band] = supp_rates |
536					ieee80211_mandatory_rates(sband,
537								  scan_width);
538				if (sta->sta.supp_rates[band] != prev_rates) {
539					ibss_dbg(sdata,
540						 "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
541						 sta->sta.addr, prev_rates,
542						 sta->sta.supp_rates[band]);
543					rates_updated = true;
544				}
545			} else {
546				rcu_read_unlock();
547				sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
548						mgmt->sa, supp_rates);
549			}
550		}
551
552		if (sta && elems->wmm_info)
553			set_sta_flag(sta, WLAN_STA_WME);
554
555		if (sta && elems->ht_operation && elems->ht_cap_elem &&
556		    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
557		    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
558		    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
559			/* we both use HT */
560			struct ieee80211_ht_cap htcap_ie;
561			struct cfg80211_chan_def chandef;
562
563			ieee80211_ht_oper_to_chandef(channel,
564						     elems->ht_operation,
565						     &chandef);
566
567			memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
568
569			/*
570			 * fall back to HT20 if we don't use or use
571			 * the other extension channel
572			 */
573			if (chandef.center_freq1 !=
574			    sdata->u.ibss.chandef.center_freq1)
575				htcap_ie.cap_info &=
576					cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40);
577
578			rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(
579						sdata, sband, &htcap_ie, sta);
580		}
581
582		if (sta && rates_updated) {
583			drv_sta_rc_update(local, sdata, &sta->sta,
584					  IEEE80211_RC_SUPP_RATES_CHANGED);
585			rate_control_rate_init(sta);
586		}
587
588		rcu_read_unlock();
589	}
590
591	bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
592					channel);
593	if (!bss)
594		return;
595
596	cbss = container_of((void *)bss, struct cfg80211_bss, priv);
597
598	/* same for beacon and probe response */
599	beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
600
601	/* check if we need to merge IBSS */
602
603	/* we use a fixed BSSID */
604	if (sdata->u.ibss.fixed_bssid)
605		goto put_bss;
606
607	/* not an IBSS */
608	if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
609		goto put_bss;
610
611	/* different channel */
612	if (sdata->u.ibss.fixed_channel &&
613	    sdata->u.ibss.chandef.chan != cbss->channel)
614		goto put_bss;
615
616	/* different SSID */
617	if (elems->ssid_len != sdata->u.ibss.ssid_len ||
618	    memcmp(elems->ssid, sdata->u.ibss.ssid,
619				sdata->u.ibss.ssid_len))
620		goto put_bss;
621
622	/* same BSSID */
623	if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
624		goto put_bss;
625
626	if (ieee80211_have_rx_timestamp(rx_status)) {
627		/* time when timestamp field was received */
628		rx_timestamp =
629			ieee80211_calculate_rx_timestamp(local, rx_status,
630							 len + FCS_LEN, 24);
631	} else {
632		/*
633		 * second best option: get current TSF
634		 * (will return -1 if not supported)
635		 */
636		rx_timestamp = drv_get_tsf(local, sdata);
637	}
638
639	ibss_dbg(sdata,
640		 "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
641		 mgmt->sa, mgmt->bssid,
642		 (unsigned long long)rx_timestamp,
643		 (unsigned long long)beacon_timestamp,
644		 (unsigned long long)(rx_timestamp - beacon_timestamp),
645		 jiffies);
646
647	if (beacon_timestamp > rx_timestamp) {
648		ibss_dbg(sdata,
649			 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
650			 mgmt->bssid);
651		ieee80211_sta_join_ibss(sdata, bss);
652		supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
653		ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
654				       supp_rates);
655		rcu_read_unlock();
656	}
657
658 put_bss:
659	ieee80211_rx_bss_put(local, bss);
660}
661
662void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
663			      const u8 *bssid, const u8 *addr,
664			      u32 supp_rates)
665{
666	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
667	struct ieee80211_local *local = sdata->local;
668	struct sta_info *sta;
669	struct ieee80211_chanctx_conf *chanctx_conf;
670	struct ieee80211_supported_band *sband;
671	enum nl80211_bss_scan_width scan_width;
672	int band;
673
674	/*
675	 * XXX: Consider removing the least recently used entry and
676	 * 	allow new one to be added.
677	 */
678	if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
679		net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
680				    sdata->name, addr);
681		return;
682	}
683
684	if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
685		return;
686
687	if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
688		return;
689
690	rcu_read_lock();
691	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
692	if (WARN_ON_ONCE(!chanctx_conf)) {
693		rcu_read_unlock();
694		return;
695	}
696	band = chanctx_conf->def.chan->band;
697	scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
698	rcu_read_unlock();
699
700	sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
701	if (!sta)
702		return;
703
704	sta->last_rx = jiffies;
705
706	/* make sure mandatory rates are always added */
707	sband = local->hw.wiphy->bands[band];
708	sta->sta.supp_rates[band] = supp_rates |
709			ieee80211_mandatory_rates(sband, scan_width);
710
711	spin_lock(&ifibss->incomplete_lock);
712	list_add(&sta->list, &ifibss->incomplete_stations);
713	spin_unlock(&ifibss->incomplete_lock);
714	ieee80211_queue_work(&local->hw, &sdata->work);
715}
716
717static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
718{
719	struct ieee80211_local *local = sdata->local;
720	int active = 0;
721	struct sta_info *sta;
722
723	sdata_assert_lock(sdata);
724
725	rcu_read_lock();
726
727	list_for_each_entry_rcu(sta, &local->sta_list, list) {
728		if (sta->sdata == sdata &&
729		    time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
730			       jiffies)) {
731			active++;
732			break;
733		}
734	}
735
736	rcu_read_unlock();
737
738	return active;
739}
740
741/*
742 * This function is called with state == IEEE80211_IBSS_MLME_JOINED
743 */
744
745static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
746{
747	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
748	enum nl80211_bss_scan_width scan_width;
749
750	sdata_assert_lock(sdata);
751
752	mod_timer(&ifibss->timer,
753		  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
754
755	ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
756
757	if (time_before(jiffies, ifibss->last_scan_completed +
758		       IEEE80211_IBSS_MERGE_INTERVAL))
759		return;
760
761	if (ieee80211_sta_active_ibss(sdata))
762		return;
763
764	if (ifibss->fixed_channel)
765		return;
766
767	sdata_info(sdata,
768		   "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
769
770	scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
771	ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
772				    NULL, scan_width);
773}
774
775static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
776{
777	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
778	u8 bssid[ETH_ALEN];
779	u16 capability;
780	int i;
781
782	sdata_assert_lock(sdata);
783
784	if (ifibss->fixed_bssid) {
785		memcpy(bssid, ifibss->bssid, ETH_ALEN);
786	} else {
787		/* Generate random, not broadcast, locally administered BSSID. Mix in
788		 * own MAC address to make sure that devices that do not have proper
789		 * random number generator get different BSSID. */
790		get_random_bytes(bssid, ETH_ALEN);
791		for (i = 0; i < ETH_ALEN; i++)
792			bssid[i] ^= sdata->vif.addr[i];
793		bssid[0] &= ~0x01;
794		bssid[0] |= 0x02;
795	}
796
797	sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
798
799	capability = WLAN_CAPABILITY_IBSS;
800
801	if (ifibss->privacy)
802		capability |= WLAN_CAPABILITY_PRIVACY;
803	else
804		sdata->drop_unencrypted = 0;
805
806	__ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
807				  ifibss->chandef.chan, ifibss->basic_rates,
808				  capability, 0, true);
809}
810
811/*
812 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
813 */
814
815static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
816{
817	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
818	struct ieee80211_local *local = sdata->local;
819	struct cfg80211_bss *cbss;
820	struct ieee80211_channel *chan = NULL;
821	const u8 *bssid = NULL;
822	enum nl80211_bss_scan_width scan_width;
823	int active_ibss;
824	u16 capability;
825
826	sdata_assert_lock(sdata);
827
828	active_ibss = ieee80211_sta_active_ibss(sdata);
829	ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
830
831	if (active_ibss)
832		return;
833
834	capability = WLAN_CAPABILITY_IBSS;
835	if (ifibss->privacy)
836		capability |= WLAN_CAPABILITY_PRIVACY;
837	if (ifibss->fixed_bssid)
838		bssid = ifibss->bssid;
839	if (ifibss->fixed_channel)
840		chan = ifibss->chandef.chan;
841	if (!is_zero_ether_addr(ifibss->bssid))
842		bssid = ifibss->bssid;
843	cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
844				ifibss->ssid, ifibss->ssid_len,
845				WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
846				capability);
847
848	if (cbss) {
849		struct ieee80211_bss *bss;
850
851		bss = (void *)cbss->priv;
852		ibss_dbg(sdata,
853			 "sta_find_ibss: selected %pM current %pM\n",
854			 cbss->bssid, ifibss->bssid);
855		sdata_info(sdata,
856			   "Selected IBSS BSSID %pM based on configured SSID\n",
857			   cbss->bssid);
858
859		ieee80211_sta_join_ibss(sdata, bss);
860		ieee80211_rx_bss_put(local, bss);
861		return;
862	}
863
864	ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
865
866	/* Selected IBSS not found in current scan results - try to scan */
867	if (time_after(jiffies, ifibss->last_scan_completed +
868					IEEE80211_SCAN_INTERVAL)) {
869		sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
870
871		scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
872		ieee80211_request_ibss_scan(sdata, ifibss->ssid,
873					    ifibss->ssid_len, chan,
874					    scan_width);
875	} else {
876		int interval = IEEE80211_SCAN_INTERVAL;
877
878		if (time_after(jiffies, ifibss->ibss_join_req +
879			       IEEE80211_IBSS_JOIN_TIMEOUT))
880			ieee80211_sta_create_ibss(sdata);
881
882		mod_timer(&ifibss->timer,
883			  round_jiffies(jiffies + interval));
884	}
885}
886
887static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
888					struct sk_buff *req)
889{
890	struct ieee80211_mgmt *mgmt = (void *)req->data;
891	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
892	struct ieee80211_local *local = sdata->local;
893	int tx_last_beacon, len = req->len;
894	struct sk_buff *skb;
895	struct beacon_data *presp;
896	u8 *pos, *end;
897
898	sdata_assert_lock(sdata);
899
900	presp = rcu_dereference_protected(ifibss->presp,
901					  lockdep_is_held(&sdata->wdev.mtx));
902
903	if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
904	    len < 24 + 2 || !presp)
905		return;
906
907	tx_last_beacon = drv_tx_last_beacon(local);
908
909	ibss_dbg(sdata,
910		 "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
911		 mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
912
913	if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
914		return;
915
916	if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
917	    !is_broadcast_ether_addr(mgmt->bssid))
918		return;
919
920	end = ((u8 *) mgmt) + len;
921	pos = mgmt->u.probe_req.variable;
922	if (pos[0] != WLAN_EID_SSID ||
923	    pos + 2 + pos[1] > end) {
924		ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
925			 mgmt->sa);
926		return;
927	}
928	if (pos[1] != 0 &&
929	    (pos[1] != ifibss->ssid_len ||
930	     memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
931		/* Ignore ProbeReq for foreign SSID */
932		return;
933	}
934
935	/* Reply with ProbeResp */
936	skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
937	if (!skb)
938		return;
939
940	skb_reserve(skb, local->tx_headroom);
941	memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
942
943	memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
944	ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
945	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
946	ieee80211_tx_skb(sdata, skb);
947}
948
949static
950void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
951				    struct ieee80211_mgmt *mgmt, size_t len,
952				    struct ieee80211_rx_status *rx_status)
953{
954	size_t baselen;
955	struct ieee802_11_elems elems;
956
957	BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
958		     offsetof(typeof(mgmt->u.beacon), variable));
959
960	/*
961	 * either beacon or probe_resp but the variable field is at the
962	 * same offset
963	 */
964	baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
965	if (baselen > len)
966		return;
967
968	ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
969			       false, &elems);
970
971	ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
972}
973
974void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
975				   struct sk_buff *skb)
976{
977	struct ieee80211_rx_status *rx_status;
978	struct ieee80211_mgmt *mgmt;
979	u16 fc;
980
981	rx_status = IEEE80211_SKB_RXCB(skb);
982	mgmt = (struct ieee80211_mgmt *) skb->data;
983	fc = le16_to_cpu(mgmt->frame_control);
984
985	sdata_lock(sdata);
986
987	if (!sdata->u.ibss.ssid_len)
988		goto mgmt_out; /* not ready to merge yet */
989
990	switch (fc & IEEE80211_FCTL_STYPE) {
991	case IEEE80211_STYPE_PROBE_REQ:
992		ieee80211_rx_mgmt_probe_req(sdata, skb);
993		break;
994	case IEEE80211_STYPE_PROBE_RESP:
995	case IEEE80211_STYPE_BEACON:
996		ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
997					       rx_status);
998		break;
999	case IEEE80211_STYPE_AUTH:
1000		ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1001		break;
1002	case IEEE80211_STYPE_DEAUTH:
1003		ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1004		break;
1005	}
1006
1007 mgmt_out:
1008	sdata_unlock(sdata);
1009}
1010
1011void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1012{
1013	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1014	struct sta_info *sta;
1015
1016	sdata_lock(sdata);
1017
1018	/*
1019	 * Work could be scheduled after scan or similar
1020	 * when we aren't even joined (or trying) with a
1021	 * network.
1022	 */
1023	if (!ifibss->ssid_len)
1024		goto out;
1025
1026	spin_lock_bh(&ifibss->incomplete_lock);
1027	while (!list_empty(&ifibss->incomplete_stations)) {
1028		sta = list_first_entry(&ifibss->incomplete_stations,
1029				       struct sta_info, list);
1030		list_del(&sta->list);
1031		spin_unlock_bh(&ifibss->incomplete_lock);
1032
1033		ieee80211_ibss_finish_sta(sta);
1034		rcu_read_unlock();
1035		spin_lock_bh(&ifibss->incomplete_lock);
1036	}
1037	spin_unlock_bh(&ifibss->incomplete_lock);
1038
1039	switch (ifibss->state) {
1040	case IEEE80211_IBSS_MLME_SEARCH:
1041		ieee80211_sta_find_ibss(sdata);
1042		break;
1043	case IEEE80211_IBSS_MLME_JOINED:
1044		ieee80211_sta_merge_ibss(sdata);
1045		break;
1046	default:
1047		WARN_ON(1);
1048		break;
1049	}
1050
1051 out:
1052	sdata_unlock(sdata);
1053}
1054
1055static void ieee80211_ibss_timer(unsigned long data)
1056{
1057	struct ieee80211_sub_if_data *sdata =
1058		(struct ieee80211_sub_if_data *) data;
1059
1060	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1061}
1062
1063void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1064{
1065	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1066
1067	setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1068		    (unsigned long) sdata);
1069	INIT_LIST_HEAD(&ifibss->incomplete_stations);
1070	spin_lock_init(&ifibss->incomplete_lock);
1071}
1072
1073/* scan finished notification */
1074void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1075{
1076	struct ieee80211_sub_if_data *sdata;
1077
1078	mutex_lock(&local->iflist_mtx);
1079	list_for_each_entry(sdata, &local->interfaces, list) {
1080		if (!ieee80211_sdata_running(sdata))
1081			continue;
1082		if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1083			continue;
1084		sdata->u.ibss.last_scan_completed = jiffies;
1085		ieee80211_queue_work(&local->hw, &sdata->work);
1086	}
1087	mutex_unlock(&local->iflist_mtx);
1088}
1089
1090int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1091			struct cfg80211_ibss_params *params)
1092{
1093	u32 changed = 0;
1094	u32 rate_flags;
1095	struct ieee80211_supported_band *sband;
1096	int i;
1097
1098	if (params->bssid) {
1099		memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1100		sdata->u.ibss.fixed_bssid = true;
1101	} else
1102		sdata->u.ibss.fixed_bssid = false;
1103
1104	sdata->u.ibss.privacy = params->privacy;
1105	sdata->u.ibss.control_port = params->control_port;
1106	sdata->u.ibss.basic_rates = params->basic_rates;
1107
1108	/* fix basic_rates if channel does not support these rates */
1109	rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1110	sband = sdata->local->hw.wiphy->bands[params->chandef.chan->band];
1111	for (i = 0; i < sband->n_bitrates; i++) {
1112		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1113			sdata->u.ibss.basic_rates &= ~BIT(i);
1114	}
1115	memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1116	       sizeof(params->mcast_rate));
1117
1118	sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1119
1120	sdata->u.ibss.chandef = params->chandef;
1121	sdata->u.ibss.fixed_channel = params->channel_fixed;
1122
1123	if (params->ie) {
1124		sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1125					   GFP_KERNEL);
1126		if (sdata->u.ibss.ie)
1127			sdata->u.ibss.ie_len = params->ie_len;
1128	}
1129
1130	sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1131	sdata->u.ibss.ibss_join_req = jiffies;
1132
1133	memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1134	sdata->u.ibss.ssid_len = params->ssid_len;
1135
1136	memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1137	       sizeof(sdata->u.ibss.ht_capa));
1138	memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1139	       sizeof(sdata->u.ibss.ht_capa_mask));
1140
1141	/*
1142	 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1143	 * reserved, but an HT STA shall protect HT transmissions as though
1144	 * the HT Protection field were set to non-HT mixed mode.
1145	 *
1146	 * In an IBSS, the RIFS Mode field of the HT Operation element is
1147	 * also reserved, but an HT STA shall operate as though this field
1148	 * were set to 1.
1149	 */
1150
1151	sdata->vif.bss_conf.ht_operation_mode |=
1152		  IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1153		| IEEE80211_HT_PARAM_RIFS_MODE;
1154
1155	changed |= BSS_CHANGED_HT;
1156	ieee80211_bss_info_change_notify(sdata, changed);
1157
1158	sdata->smps_mode = IEEE80211_SMPS_OFF;
1159	sdata->needed_rx_chains = sdata->local->rx_chains;
1160
1161	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1162
1163	return 0;
1164}
1165
1166int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1167{
1168	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1169	struct ieee80211_local *local = sdata->local;
1170	struct cfg80211_bss *cbss;
1171	u16 capability;
1172	int active_ibss;
1173	struct sta_info *sta;
1174	struct beacon_data *presp;
1175
1176	active_ibss = ieee80211_sta_active_ibss(sdata);
1177
1178	if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
1179		capability = WLAN_CAPABILITY_IBSS;
1180
1181		if (ifibss->privacy)
1182			capability |= WLAN_CAPABILITY_PRIVACY;
1183
1184		cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
1185					ifibss->bssid, ifibss->ssid,
1186					ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
1187					WLAN_CAPABILITY_PRIVACY,
1188					capability);
1189
1190		if (cbss) {
1191			cfg80211_unlink_bss(local->hw.wiphy, cbss);
1192			cfg80211_put_bss(local->hw.wiphy, cbss);
1193		}
1194	}
1195
1196	ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
1197	memset(ifibss->bssid, 0, ETH_ALEN);
1198	ifibss->ssid_len = 0;
1199
1200	sta_info_flush(sdata);
1201
1202	spin_lock_bh(&ifibss->incomplete_lock);
1203	while (!list_empty(&ifibss->incomplete_stations)) {
1204		sta = list_first_entry(&ifibss->incomplete_stations,
1205				       struct sta_info, list);
1206		list_del(&sta->list);
1207		spin_unlock_bh(&ifibss->incomplete_lock);
1208
1209		sta_info_free(local, sta);
1210		spin_lock_bh(&ifibss->incomplete_lock);
1211	}
1212	spin_unlock_bh(&ifibss->incomplete_lock);
1213
1214	netif_carrier_off(sdata->dev);
1215
1216	/* remove beacon */
1217	kfree(sdata->u.ibss.ie);
1218	presp = rcu_dereference_protected(ifibss->presp,
1219					  lockdep_is_held(&sdata->wdev.mtx));
1220	RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
1221
1222	/* on the next join, re-program HT parameters */
1223	memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1224	memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1225
1226	sdata->vif.bss_conf.ibss_joined = false;
1227	sdata->vif.bss_conf.ibss_creator = false;
1228	sdata->vif.bss_conf.enable_beacon = false;
1229	sdata->vif.bss_conf.ssid_len = 0;
1230	clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
1231	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
1232						BSS_CHANGED_IBSS);
1233	synchronize_rcu();
1234	kfree(presp);
1235
1236	skb_queue_purge(&sdata->skb_queue);
1237
1238	del_timer_sync(&sdata->u.ibss.timer);
1239
1240	return 0;
1241}
1242