xref: /linux/net/mac80211/ibss.c (revision c0e297dc61f8d4453e07afbea1fa8d0e67cd4a34)
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  * Copyright 2013-2014  Intel Mobile Communications GmbH
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License version 2 as
13  * published by the Free Software Foundation.
14  */
15 
16 #include <linux/delay.h>
17 #include <linux/slab.h>
18 #include <linux/if_ether.h>
19 #include <linux/skbuff.h>
20 #include <linux/if_arp.h>
21 #include <linux/etherdevice.h>
22 #include <linux/rtnetlink.h>
23 #include <net/mac80211.h>
24 
25 #include "ieee80211_i.h"
26 #include "driver-ops.h"
27 #include "rate.h"
28 
29 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
30 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
31 
32 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
33 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
34 #define IEEE80211_IBSS_RSN_INACTIVITY_LIMIT (10 * HZ)
35 
36 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
37 
38 static struct beacon_data *
39 ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
40 			   const int beacon_int, const u32 basic_rates,
41 			   const u16 capability, u64 tsf,
42 			   struct cfg80211_chan_def *chandef,
43 			   bool *have_higher_than_11mbit,
44 			   struct cfg80211_csa_settings *csa_settings)
45 {
46 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
47 	struct ieee80211_local *local = sdata->local;
48 	int rates_n = 0, i, ri;
49 	struct ieee80211_mgmt *mgmt;
50 	u8 *pos;
51 	struct ieee80211_supported_band *sband;
52 	u32 rate_flags, rates = 0, rates_added = 0;
53 	struct beacon_data *presp;
54 	int frame_len;
55 	int shift;
56 
57 	/* Build IBSS probe response */
58 	frame_len = sizeof(struct ieee80211_hdr_3addr) +
59 		    12 /* struct ieee80211_mgmt.u.beacon */ +
60 		    2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
61 		    2 + 8 /* max Supported Rates */ +
62 		    3 /* max DS params */ +
63 		    4 /* IBSS params */ +
64 		    5 /* Channel Switch Announcement */ +
65 		    2 + (IEEE80211_MAX_SUPP_RATES - 8) +
66 		    2 + sizeof(struct ieee80211_ht_cap) +
67 		    2 + sizeof(struct ieee80211_ht_operation) +
68 		    ifibss->ie_len;
69 	presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
70 	if (!presp)
71 		return NULL;
72 
73 	presp->head = (void *)(presp + 1);
74 
75 	mgmt = (void *) presp->head;
76 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
77 					  IEEE80211_STYPE_PROBE_RESP);
78 	eth_broadcast_addr(mgmt->da);
79 	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
80 	memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
81 	mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
82 	mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
83 	mgmt->u.beacon.capab_info = cpu_to_le16(capability);
84 
85 	pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
86 
87 	*pos++ = WLAN_EID_SSID;
88 	*pos++ = ifibss->ssid_len;
89 	memcpy(pos, ifibss->ssid, ifibss->ssid_len);
90 	pos += ifibss->ssid_len;
91 
92 	sband = local->hw.wiphy->bands[chandef->chan->band];
93 	rate_flags = ieee80211_chandef_rate_flags(chandef);
94 	shift = ieee80211_chandef_get_shift(chandef);
95 	rates_n = 0;
96 	if (have_higher_than_11mbit)
97 		*have_higher_than_11mbit = false;
98 
99 	for (i = 0; i < sband->n_bitrates; i++) {
100 		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
101 			continue;
102 		if (sband->bitrates[i].bitrate > 110 &&
103 		    have_higher_than_11mbit)
104 			*have_higher_than_11mbit = true;
105 
106 		rates |= BIT(i);
107 		rates_n++;
108 	}
109 
110 	*pos++ = WLAN_EID_SUPP_RATES;
111 	*pos++ = min_t(int, 8, rates_n);
112 	for (ri = 0; ri < sband->n_bitrates; ri++) {
113 		int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
114 					5 * (1 << shift));
115 		u8 basic = 0;
116 		if (!(rates & BIT(ri)))
117 			continue;
118 
119 		if (basic_rates & BIT(ri))
120 			basic = 0x80;
121 		*pos++ = basic | (u8) rate;
122 		if (++rates_added == 8) {
123 			ri++; /* continue at next rate for EXT_SUPP_RATES */
124 			break;
125 		}
126 	}
127 
128 	if (sband->band == IEEE80211_BAND_2GHZ) {
129 		*pos++ = WLAN_EID_DS_PARAMS;
130 		*pos++ = 1;
131 		*pos++ = ieee80211_frequency_to_channel(
132 				chandef->chan->center_freq);
133 	}
134 
135 	*pos++ = WLAN_EID_IBSS_PARAMS;
136 	*pos++ = 2;
137 	/* FIX: set ATIM window based on scan results */
138 	*pos++ = 0;
139 	*pos++ = 0;
140 
141 	if (csa_settings) {
142 		*pos++ = WLAN_EID_CHANNEL_SWITCH;
143 		*pos++ = 3;
144 		*pos++ = csa_settings->block_tx ? 1 : 0;
145 		*pos++ = ieee80211_frequency_to_channel(
146 				csa_settings->chandef.chan->center_freq);
147 		presp->csa_counter_offsets[0] = (pos - presp->head);
148 		*pos++ = csa_settings->count;
149 		presp->csa_current_counter = csa_settings->count;
150 	}
151 
152 	/* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
153 	if (rates_n > 8) {
154 		*pos++ = WLAN_EID_EXT_SUPP_RATES;
155 		*pos++ = rates_n - 8;
156 		for (; ri < sband->n_bitrates; ri++) {
157 			int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
158 						5 * (1 << shift));
159 			u8 basic = 0;
160 			if (!(rates & BIT(ri)))
161 				continue;
162 
163 			if (basic_rates & BIT(ri))
164 				basic = 0x80;
165 			*pos++ = basic | (u8) rate;
166 		}
167 	}
168 
169 	if (ifibss->ie_len) {
170 		memcpy(pos, ifibss->ie, ifibss->ie_len);
171 		pos += ifibss->ie_len;
172 	}
173 
174 	/* add HT capability and information IEs */
175 	if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT &&
176 	    chandef->width != NL80211_CHAN_WIDTH_5 &&
177 	    chandef->width != NL80211_CHAN_WIDTH_10 &&
178 	    sband->ht_cap.ht_supported) {
179 		struct ieee80211_sta_ht_cap ht_cap;
180 
181 		memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
182 		ieee80211_apply_htcap_overrides(sdata, &ht_cap);
183 
184 		pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
185 		/*
186 		 * Note: According to 802.11n-2009 9.13.3.1, HT Protection
187 		 * field and RIFS Mode are reserved in IBSS mode, therefore
188 		 * keep them at 0
189 		 */
190 		pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
191 						 chandef, 0);
192 
193 		/* add VHT capability and information IEs */
194 		if (chandef->width != NL80211_CHAN_WIDTH_20 &&
195 		    chandef->width != NL80211_CHAN_WIDTH_40 &&
196 		    sband->vht_cap.vht_supported) {
197 			pos = ieee80211_ie_build_vht_cap(pos, &sband->vht_cap,
198 							 sband->vht_cap.cap);
199 			pos = ieee80211_ie_build_vht_oper(pos, &sband->vht_cap,
200 							  chandef);
201 		}
202 	}
203 
204 	if (local->hw.queues >= IEEE80211_NUM_ACS)
205 		pos = ieee80211_add_wmm_info_ie(pos, 0); /* U-APSD not in use */
206 
207 	presp->head_len = pos - presp->head;
208 	if (WARN_ON(presp->head_len > frame_len))
209 		goto error;
210 
211 	return presp;
212 error:
213 	kfree(presp);
214 	return NULL;
215 }
216 
217 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
218 				      const u8 *bssid, const int beacon_int,
219 				      struct cfg80211_chan_def *req_chandef,
220 				      const u32 basic_rates,
221 				      const u16 capability, u64 tsf,
222 				      bool creator)
223 {
224 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
225 	struct ieee80211_local *local = sdata->local;
226 	struct ieee80211_mgmt *mgmt;
227 	struct cfg80211_bss *bss;
228 	u32 bss_change;
229 	struct cfg80211_chan_def chandef;
230 	struct ieee80211_channel *chan;
231 	struct beacon_data *presp;
232 	enum nl80211_bss_scan_width scan_width;
233 	bool have_higher_than_11mbit;
234 	bool radar_required;
235 	int err;
236 
237 	sdata_assert_lock(sdata);
238 
239 	/* Reset own TSF to allow time synchronization work. */
240 	drv_reset_tsf(local, sdata);
241 
242 	if (!ether_addr_equal(ifibss->bssid, bssid))
243 		sta_info_flush(sdata);
244 
245 	/* if merging, indicate to driver that we leave the old IBSS */
246 	if (sdata->vif.bss_conf.ibss_joined) {
247 		sdata->vif.bss_conf.ibss_joined = false;
248 		sdata->vif.bss_conf.ibss_creator = false;
249 		sdata->vif.bss_conf.enable_beacon = false;
250 		netif_carrier_off(sdata->dev);
251 		ieee80211_bss_info_change_notify(sdata,
252 						 BSS_CHANGED_IBSS |
253 						 BSS_CHANGED_BEACON_ENABLED);
254 		drv_leave_ibss(local, sdata);
255 	}
256 
257 	presp = rcu_dereference_protected(ifibss->presp,
258 					  lockdep_is_held(&sdata->wdev.mtx));
259 	RCU_INIT_POINTER(ifibss->presp, NULL);
260 	if (presp)
261 		kfree_rcu(presp, rcu_head);
262 
263 	/* make a copy of the chandef, it could be modified below. */
264 	chandef = *req_chandef;
265 	chan = chandef.chan;
266 	if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
267 				     NL80211_IFTYPE_ADHOC)) {
268 		if (chandef.width == NL80211_CHAN_WIDTH_5 ||
269 		    chandef.width == NL80211_CHAN_WIDTH_10 ||
270 		    chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
271 		    chandef.width == NL80211_CHAN_WIDTH_20) {
272 			sdata_info(sdata,
273 				   "Failed to join IBSS, beacons forbidden\n");
274 			return;
275 		}
276 		chandef.width = NL80211_CHAN_WIDTH_20;
277 		chandef.center_freq1 = chan->center_freq;
278 		/* check again for downgraded chandef */
279 		if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
280 					     NL80211_IFTYPE_ADHOC)) {
281 			sdata_info(sdata,
282 				   "Failed to join IBSS, beacons forbidden\n");
283 			return;
284 		}
285 	}
286 
287 	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
288 					    &chandef, NL80211_IFTYPE_ADHOC);
289 	if (err < 0) {
290 		sdata_info(sdata,
291 			   "Failed to join IBSS, invalid chandef\n");
292 		return;
293 	}
294 	if (err > 0 && !ifibss->userspace_handles_dfs) {
295 		sdata_info(sdata,
296 			   "Failed to join IBSS, DFS channel without control program\n");
297 		return;
298 	}
299 
300 	radar_required = err;
301 
302 	mutex_lock(&local->mtx);
303 	if (ieee80211_vif_use_channel(sdata, &chandef,
304 				      ifibss->fixed_channel ?
305 					IEEE80211_CHANCTX_SHARED :
306 					IEEE80211_CHANCTX_EXCLUSIVE)) {
307 		sdata_info(sdata, "Failed to join IBSS, no channel context\n");
308 		mutex_unlock(&local->mtx);
309 		return;
310 	}
311 	sdata->radar_required = radar_required;
312 	mutex_unlock(&local->mtx);
313 
314 	memcpy(ifibss->bssid, bssid, ETH_ALEN);
315 
316 	presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
317 					   capability, tsf, &chandef,
318 					   &have_higher_than_11mbit, NULL);
319 	if (!presp)
320 		return;
321 
322 	rcu_assign_pointer(ifibss->presp, presp);
323 	mgmt = (void *)presp->head;
324 
325 	sdata->vif.bss_conf.enable_beacon = true;
326 	sdata->vif.bss_conf.beacon_int = beacon_int;
327 	sdata->vif.bss_conf.basic_rates = basic_rates;
328 	sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
329 	memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
330 	bss_change = BSS_CHANGED_BEACON_INT;
331 	bss_change |= ieee80211_reset_erp_info(sdata);
332 	bss_change |= BSS_CHANGED_BSSID;
333 	bss_change |= BSS_CHANGED_BEACON;
334 	bss_change |= BSS_CHANGED_BEACON_ENABLED;
335 	bss_change |= BSS_CHANGED_BASIC_RATES;
336 	bss_change |= BSS_CHANGED_HT;
337 	bss_change |= BSS_CHANGED_IBSS;
338 	bss_change |= BSS_CHANGED_SSID;
339 
340 	/*
341 	 * In 5 GHz/802.11a, we can always use short slot time.
342 	 * (IEEE 802.11-2012 18.3.8.7)
343 	 *
344 	 * In 2.4GHz, we must always use long slots in IBSS for compatibility
345 	 * reasons.
346 	 * (IEEE 802.11-2012 19.4.5)
347 	 *
348 	 * HT follows these specifications (IEEE 802.11-2012 20.3.18)
349 	 */
350 	sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
351 	bss_change |= BSS_CHANGED_ERP_SLOT;
352 
353 	/* cf. IEEE 802.11 9.2.12 */
354 	if (chan->band == IEEE80211_BAND_2GHZ && have_higher_than_11mbit)
355 		sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
356 	else
357 		sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
358 
359 	ieee80211_set_wmm_default(sdata, true);
360 
361 	sdata->vif.bss_conf.ibss_joined = true;
362 	sdata->vif.bss_conf.ibss_creator = creator;
363 
364 	err = drv_join_ibss(local, sdata);
365 	if (err) {
366 		sdata->vif.bss_conf.ibss_joined = false;
367 		sdata->vif.bss_conf.ibss_creator = false;
368 		sdata->vif.bss_conf.enable_beacon = false;
369 		sdata->vif.bss_conf.ssid_len = 0;
370 		RCU_INIT_POINTER(ifibss->presp, NULL);
371 		kfree_rcu(presp, rcu_head);
372 		mutex_lock(&local->mtx);
373 		ieee80211_vif_release_channel(sdata);
374 		mutex_unlock(&local->mtx);
375 		sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
376 			   err);
377 		return;
378 	}
379 
380 	ieee80211_bss_info_change_notify(sdata, bss_change);
381 
382 	ifibss->state = IEEE80211_IBSS_MLME_JOINED;
383 	mod_timer(&ifibss->timer,
384 		  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
385 
386 	scan_width = cfg80211_chandef_to_scan_width(&chandef);
387 	bss = cfg80211_inform_bss_width_frame(local->hw.wiphy, chan,
388 					      scan_width, mgmt,
389 					      presp->head_len, 0, GFP_KERNEL);
390 	cfg80211_put_bss(local->hw.wiphy, bss);
391 	netif_carrier_on(sdata->dev);
392 	cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
393 }
394 
395 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
396 				    struct ieee80211_bss *bss)
397 {
398 	struct cfg80211_bss *cbss =
399 		container_of((void *)bss, struct cfg80211_bss, priv);
400 	struct ieee80211_supported_band *sband;
401 	struct cfg80211_chan_def chandef;
402 	u32 basic_rates;
403 	int i, j;
404 	u16 beacon_int = cbss->beacon_interval;
405 	const struct cfg80211_bss_ies *ies;
406 	enum nl80211_channel_type chan_type;
407 	u64 tsf;
408 	u32 rate_flags;
409 	int shift;
410 
411 	sdata_assert_lock(sdata);
412 
413 	if (beacon_int < 10)
414 		beacon_int = 10;
415 
416 	switch (sdata->u.ibss.chandef.width) {
417 	case NL80211_CHAN_WIDTH_20_NOHT:
418 	case NL80211_CHAN_WIDTH_20:
419 	case NL80211_CHAN_WIDTH_40:
420 		chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
421 		cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
422 		break;
423 	case NL80211_CHAN_WIDTH_5:
424 	case NL80211_CHAN_WIDTH_10:
425 		cfg80211_chandef_create(&chandef, cbss->channel,
426 					NL80211_CHAN_WIDTH_20_NOHT);
427 		chandef.width = sdata->u.ibss.chandef.width;
428 		break;
429 	case NL80211_CHAN_WIDTH_80:
430 	case NL80211_CHAN_WIDTH_160:
431 		chandef = sdata->u.ibss.chandef;
432 		chandef.chan = cbss->channel;
433 		break;
434 	default:
435 		/* fall back to 20 MHz for unsupported modes */
436 		cfg80211_chandef_create(&chandef, cbss->channel,
437 					NL80211_CHAN_WIDTH_20_NOHT);
438 		break;
439 	}
440 
441 	sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
442 	rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
443 	shift = ieee80211_vif_get_shift(&sdata->vif);
444 
445 	basic_rates = 0;
446 
447 	for (i = 0; i < bss->supp_rates_len; i++) {
448 		int rate = bss->supp_rates[i] & 0x7f;
449 		bool is_basic = !!(bss->supp_rates[i] & 0x80);
450 
451 		for (j = 0; j < sband->n_bitrates; j++) {
452 			int brate;
453 			if ((rate_flags & sband->bitrates[j].flags)
454 			    != rate_flags)
455 				continue;
456 
457 			brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
458 					     5 * (1 << shift));
459 			if (brate == rate) {
460 				if (is_basic)
461 					basic_rates |= BIT(j);
462 				break;
463 			}
464 		}
465 	}
466 
467 	rcu_read_lock();
468 	ies = rcu_dereference(cbss->ies);
469 	tsf = ies->tsf;
470 	rcu_read_unlock();
471 
472 	__ieee80211_sta_join_ibss(sdata, cbss->bssid,
473 				  beacon_int,
474 				  &chandef,
475 				  basic_rates,
476 				  cbss->capability,
477 				  tsf, false);
478 }
479 
480 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
481 			      struct cfg80211_csa_settings *csa_settings)
482 {
483 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
484 	struct beacon_data *presp, *old_presp;
485 	struct cfg80211_bss *cbss;
486 	const struct cfg80211_bss_ies *ies;
487 	u16 capability = 0;
488 	u64 tsf;
489 	int ret = 0;
490 
491 	sdata_assert_lock(sdata);
492 
493 	if (ifibss->privacy)
494 		capability = WLAN_CAPABILITY_PRIVACY;
495 
496 	cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
497 				ifibss->bssid, ifibss->ssid,
498 				ifibss->ssid_len, IEEE80211_BSS_TYPE_IBSS,
499 				IEEE80211_PRIVACY(ifibss->privacy));
500 
501 	if (WARN_ON(!cbss)) {
502 		ret = -EINVAL;
503 		goto out;
504 	}
505 
506 	rcu_read_lock();
507 	ies = rcu_dereference(cbss->ies);
508 	tsf = ies->tsf;
509 	rcu_read_unlock();
510 	cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
511 
512 	old_presp = rcu_dereference_protected(ifibss->presp,
513 					  lockdep_is_held(&sdata->wdev.mtx));
514 
515 	presp = ieee80211_ibss_build_presp(sdata,
516 					   sdata->vif.bss_conf.beacon_int,
517 					   sdata->vif.bss_conf.basic_rates,
518 					   capability, tsf, &ifibss->chandef,
519 					   NULL, csa_settings);
520 	if (!presp) {
521 		ret = -ENOMEM;
522 		goto out;
523 	}
524 
525 	rcu_assign_pointer(ifibss->presp, presp);
526 	if (old_presp)
527 		kfree_rcu(old_presp, rcu_head);
528 
529 	return BSS_CHANGED_BEACON;
530  out:
531 	return ret;
532 }
533 
534 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
535 {
536 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
537 	struct cfg80211_bss *cbss;
538 	int err, changed = 0;
539 
540 	sdata_assert_lock(sdata);
541 
542 	/* update cfg80211 bss information with the new channel */
543 	if (!is_zero_ether_addr(ifibss->bssid)) {
544 		cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
545 					ifibss->chandef.chan,
546 					ifibss->bssid, ifibss->ssid,
547 					ifibss->ssid_len,
548 					IEEE80211_BSS_TYPE_IBSS,
549 					IEEE80211_PRIVACY(ifibss->privacy));
550 		/* XXX: should not really modify cfg80211 data */
551 		if (cbss) {
552 			cbss->channel = sdata->csa_chandef.chan;
553 			cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
554 		}
555 	}
556 
557 	ifibss->chandef = sdata->csa_chandef;
558 
559 	/* generate the beacon */
560 	err = ieee80211_ibss_csa_beacon(sdata, NULL);
561 	if (err < 0)
562 		return err;
563 
564 	changed |= err;
565 
566 	return changed;
567 }
568 
569 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
570 {
571 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
572 
573 	cancel_work_sync(&ifibss->csa_connection_drop_work);
574 }
575 
576 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
577 	__acquires(RCU)
578 {
579 	struct ieee80211_sub_if_data *sdata = sta->sdata;
580 	u8 addr[ETH_ALEN];
581 
582 	memcpy(addr, sta->sta.addr, ETH_ALEN);
583 
584 	ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
585 
586 	sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
587 	sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
588 	/* authorize the station only if the network is not RSN protected. If
589 	 * not wait for the userspace to authorize it */
590 	if (!sta->sdata->u.ibss.control_port)
591 		sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
592 
593 	rate_control_rate_init(sta);
594 
595 	/* If it fails, maybe we raced another insertion? */
596 	if (sta_info_insert_rcu(sta))
597 		return sta_info_get(sdata, addr);
598 	return sta;
599 }
600 
601 static struct sta_info *
602 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
603 		       const u8 *addr, u32 supp_rates)
604 	__acquires(RCU)
605 {
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;
610 	struct ieee80211_supported_band *sband;
611 	enum nl80211_bss_scan_width scan_width;
612 	int band;
613 
614 	/*
615 	 * XXX: Consider removing the least recently used entry and
616 	 * 	allow new one to be added.
617 	 */
618 	if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
619 		net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
620 				    sdata->name, addr);
621 		rcu_read_lock();
622 		return NULL;
623 	}
624 
625 	if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
626 		rcu_read_lock();
627 		return NULL;
628 	}
629 
630 	if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
631 		rcu_read_lock();
632 		return NULL;
633 	}
634 
635 	rcu_read_lock();
636 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
637 	if (WARN_ON_ONCE(!chanctx_conf))
638 		return NULL;
639 	band = chanctx_conf->def.chan->band;
640 	scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
641 	rcu_read_unlock();
642 
643 	sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
644 	if (!sta) {
645 		rcu_read_lock();
646 		return NULL;
647 	}
648 
649 	sta->last_rx = jiffies;
650 
651 	/* make sure mandatory rates are always added */
652 	sband = local->hw.wiphy->bands[band];
653 	sta->sta.supp_rates[band] = supp_rates |
654 			ieee80211_mandatory_rates(sband, scan_width);
655 
656 	return ieee80211_ibss_finish_sta(sta);
657 }
658 
659 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
660 {
661 	struct ieee80211_local *local = sdata->local;
662 	int active = 0;
663 	struct sta_info *sta;
664 
665 	sdata_assert_lock(sdata);
666 
667 	rcu_read_lock();
668 
669 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
670 		if (sta->sdata == sdata &&
671 		    time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
672 			       jiffies)) {
673 			active++;
674 			break;
675 		}
676 	}
677 
678 	rcu_read_unlock();
679 
680 	return active;
681 }
682 
683 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
684 {
685 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
686 	struct ieee80211_local *local = sdata->local;
687 	struct cfg80211_bss *cbss;
688 	struct beacon_data *presp;
689 	struct sta_info *sta;
690 
691 	if (!is_zero_ether_addr(ifibss->bssid)) {
692 		cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
693 					ifibss->bssid, ifibss->ssid,
694 					ifibss->ssid_len,
695 					IEEE80211_BSS_TYPE_IBSS,
696 					IEEE80211_PRIVACY(ifibss->privacy));
697 
698 		if (cbss) {
699 			cfg80211_unlink_bss(local->hw.wiphy, cbss);
700 			cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
701 		}
702 	}
703 
704 	ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
705 
706 	sta_info_flush(sdata);
707 
708 	spin_lock_bh(&ifibss->incomplete_lock);
709 	while (!list_empty(&ifibss->incomplete_stations)) {
710 		sta = list_first_entry(&ifibss->incomplete_stations,
711 				       struct sta_info, list);
712 		list_del(&sta->list);
713 		spin_unlock_bh(&ifibss->incomplete_lock);
714 
715 		sta_info_free(local, sta);
716 		spin_lock_bh(&ifibss->incomplete_lock);
717 	}
718 	spin_unlock_bh(&ifibss->incomplete_lock);
719 
720 	netif_carrier_off(sdata->dev);
721 
722 	sdata->vif.bss_conf.ibss_joined = false;
723 	sdata->vif.bss_conf.ibss_creator = false;
724 	sdata->vif.bss_conf.enable_beacon = false;
725 	sdata->vif.bss_conf.ssid_len = 0;
726 
727 	/* remove beacon */
728 	presp = rcu_dereference_protected(ifibss->presp,
729 					  lockdep_is_held(&sdata->wdev.mtx));
730 	RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
731 	if (presp)
732 		kfree_rcu(presp, rcu_head);
733 
734 	clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
735 	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
736 						BSS_CHANGED_IBSS);
737 	drv_leave_ibss(local, sdata);
738 	mutex_lock(&local->mtx);
739 	ieee80211_vif_release_channel(sdata);
740 	mutex_unlock(&local->mtx);
741 }
742 
743 static void ieee80211_csa_connection_drop_work(struct work_struct *work)
744 {
745 	struct ieee80211_sub_if_data *sdata =
746 		container_of(work, struct ieee80211_sub_if_data,
747 			     u.ibss.csa_connection_drop_work);
748 
749 	sdata_lock(sdata);
750 
751 	ieee80211_ibss_disconnect(sdata);
752 	synchronize_rcu();
753 	skb_queue_purge(&sdata->skb_queue);
754 
755 	/* trigger a scan to find another IBSS network to join */
756 	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
757 
758 	sdata_unlock(sdata);
759 }
760 
761 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
762 {
763 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
764 	int err;
765 
766 	/* if the current channel is a DFS channel, mark the channel as
767 	 * unavailable.
768 	 */
769 	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
770 					    &ifibss->chandef,
771 					    NL80211_IFTYPE_ADHOC);
772 	if (err > 0)
773 		cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
774 				     GFP_ATOMIC);
775 }
776 
777 static bool
778 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
779 				  struct ieee802_11_elems *elems,
780 				  bool beacon)
781 {
782 	struct cfg80211_csa_settings params;
783 	struct ieee80211_csa_ie csa_ie;
784 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
785 	enum nl80211_channel_type ch_type;
786 	int err;
787 	u32 sta_flags;
788 
789 	sdata_assert_lock(sdata);
790 
791 	sta_flags = IEEE80211_STA_DISABLE_VHT;
792 	switch (ifibss->chandef.width) {
793 	case NL80211_CHAN_WIDTH_5:
794 	case NL80211_CHAN_WIDTH_10:
795 	case NL80211_CHAN_WIDTH_20_NOHT:
796 		sta_flags |= IEEE80211_STA_DISABLE_HT;
797 		/* fall through */
798 	case NL80211_CHAN_WIDTH_20:
799 		sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
800 		break;
801 	default:
802 		break;
803 	}
804 
805 	memset(&params, 0, sizeof(params));
806 	memset(&csa_ie, 0, sizeof(csa_ie));
807 	err = ieee80211_parse_ch_switch_ie(sdata, elems,
808 					   ifibss->chandef.chan->band,
809 					   sta_flags, ifibss->bssid, &csa_ie);
810 	/* can't switch to destination channel, fail */
811 	if (err < 0)
812 		goto disconnect;
813 
814 	/* did not contain a CSA */
815 	if (err)
816 		return false;
817 
818 	/* channel switch is not supported, disconnect */
819 	if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
820 		goto disconnect;
821 
822 	params.count = csa_ie.count;
823 	params.chandef = csa_ie.chandef;
824 
825 	switch (ifibss->chandef.width) {
826 	case NL80211_CHAN_WIDTH_20_NOHT:
827 	case NL80211_CHAN_WIDTH_20:
828 	case NL80211_CHAN_WIDTH_40:
829 		/* keep our current HT mode (HT20/HT40+/HT40-), even if
830 		 * another mode  has been announced. The mode is not adopted
831 		 * within the beacon while doing CSA and we should therefore
832 		 * keep the mode which we announce.
833 		 */
834 		ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
835 		cfg80211_chandef_create(&params.chandef, params.chandef.chan,
836 					ch_type);
837 		break;
838 	case NL80211_CHAN_WIDTH_5:
839 	case NL80211_CHAN_WIDTH_10:
840 		if (params.chandef.width != ifibss->chandef.width) {
841 			sdata_info(sdata,
842 				   "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
843 				   ifibss->bssid,
844 				   params.chandef.chan->center_freq,
845 				   params.chandef.width,
846 				   params.chandef.center_freq1,
847 				   params.chandef.center_freq2);
848 			goto disconnect;
849 		}
850 		break;
851 	default:
852 		/* should not happen, sta_flags should prevent VHT modes. */
853 		WARN_ON(1);
854 		goto disconnect;
855 	}
856 
857 	if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef,
858 				     NL80211_IFTYPE_ADHOC)) {
859 		sdata_info(sdata,
860 			   "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
861 			   ifibss->bssid,
862 			   params.chandef.chan->center_freq,
863 			   params.chandef.width,
864 			   params.chandef.center_freq1,
865 			   params.chandef.center_freq2);
866 		goto disconnect;
867 	}
868 
869 	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
870 					    &params.chandef,
871 					    NL80211_IFTYPE_ADHOC);
872 	if (err < 0)
873 		goto disconnect;
874 	if (err > 0 && !ifibss->userspace_handles_dfs) {
875 		/* IBSS-DFS only allowed with a control program */
876 		goto disconnect;
877 	}
878 
879 	params.radar_required = err;
880 
881 	if (cfg80211_chandef_identical(&params.chandef,
882 				       &sdata->vif.bss_conf.chandef)) {
883 		ibss_dbg(sdata,
884 			 "received csa with an identical chandef, ignoring\n");
885 		return true;
886 	}
887 
888 	/* all checks done, now perform the channel switch. */
889 	ibss_dbg(sdata,
890 		 "received channel switch announcement to go to channel %d MHz\n",
891 		 params.chandef.chan->center_freq);
892 
893 	params.block_tx = !!csa_ie.mode;
894 
895 	if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
896 				     &params))
897 		goto disconnect;
898 
899 	ieee80211_ibss_csa_mark_radar(sdata);
900 
901 	return true;
902 disconnect:
903 	ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
904 	ieee80211_queue_work(&sdata->local->hw,
905 			     &ifibss->csa_connection_drop_work);
906 
907 	ieee80211_ibss_csa_mark_radar(sdata);
908 
909 	return true;
910 }
911 
912 static void
913 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
914 				struct ieee80211_mgmt *mgmt, size_t len,
915 				struct ieee80211_rx_status *rx_status,
916 				struct ieee802_11_elems *elems)
917 {
918 	int required_len;
919 
920 	if (len < IEEE80211_MIN_ACTION_SIZE + 1)
921 		return;
922 
923 	/* CSA is the only action we handle for now */
924 	if (mgmt->u.action.u.measurement.action_code !=
925 	    WLAN_ACTION_SPCT_CHL_SWITCH)
926 		return;
927 
928 	required_len = IEEE80211_MIN_ACTION_SIZE +
929 		       sizeof(mgmt->u.action.u.chan_switch);
930 	if (len < required_len)
931 		return;
932 
933 	if (!sdata->vif.csa_active)
934 		ieee80211_ibss_process_chanswitch(sdata, elems, false);
935 }
936 
937 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
938 					  struct ieee80211_mgmt *mgmt,
939 					  size_t len)
940 {
941 	u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
942 
943 	if (len < IEEE80211_DEAUTH_FRAME_LEN)
944 		return;
945 
946 	ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
947 		 mgmt->sa, mgmt->da, mgmt->bssid, reason);
948 	sta_info_destroy_addr(sdata, mgmt->sa);
949 }
950 
951 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
952 					struct ieee80211_mgmt *mgmt,
953 					size_t len)
954 {
955 	u16 auth_alg, auth_transaction;
956 
957 	sdata_assert_lock(sdata);
958 
959 	if (len < 24 + 6)
960 		return;
961 
962 	auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
963 	auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
964 
965 	ibss_dbg(sdata,
966 		 "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
967 		 mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
968 
969 	if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
970 		return;
971 
972 	/*
973 	 * IEEE 802.11 standard does not require authentication in IBSS
974 	 * networks and most implementations do not seem to use it.
975 	 * However, try to reply to authentication attempts if someone
976 	 * has actually implemented this.
977 	 */
978 	ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
979 			    mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
980 }
981 
982 static void ieee80211_update_sta_info(struct ieee80211_sub_if_data *sdata,
983 				      struct ieee80211_mgmt *mgmt, size_t len,
984 				      struct ieee80211_rx_status *rx_status,
985 				      struct ieee802_11_elems *elems,
986 				      struct ieee80211_channel *channel)
987 {
988 	struct sta_info *sta;
989 	enum ieee80211_band band = rx_status->band;
990 	enum nl80211_bss_scan_width scan_width;
991 	struct ieee80211_local *local = sdata->local;
992 	struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
993 	bool rates_updated = false;
994 	u32 supp_rates = 0;
995 
996 	if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
997 		return;
998 
999 	if (!ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid))
1000 		return;
1001 
1002 	rcu_read_lock();
1003 	sta = sta_info_get(sdata, mgmt->sa);
1004 
1005 	if (elems->supp_rates) {
1006 		supp_rates = ieee80211_sta_get_rates(sdata, elems,
1007 						     band, NULL);
1008 		if (sta) {
1009 			u32 prev_rates;
1010 
1011 			prev_rates = sta->sta.supp_rates[band];
1012 			/* make sure mandatory rates are always added */
1013 			scan_width = NL80211_BSS_CHAN_WIDTH_20;
1014 			if (rx_status->flag & RX_FLAG_5MHZ)
1015 				scan_width = NL80211_BSS_CHAN_WIDTH_5;
1016 			if (rx_status->flag & RX_FLAG_10MHZ)
1017 				scan_width = NL80211_BSS_CHAN_WIDTH_10;
1018 
1019 			sta->sta.supp_rates[band] = supp_rates |
1020 				ieee80211_mandatory_rates(sband, scan_width);
1021 			if (sta->sta.supp_rates[band] != prev_rates) {
1022 				ibss_dbg(sdata,
1023 					 "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1024 					 sta->sta.addr, prev_rates,
1025 					 sta->sta.supp_rates[band]);
1026 				rates_updated = true;
1027 			}
1028 		} else {
1029 			rcu_read_unlock();
1030 			sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1031 						     mgmt->sa, supp_rates);
1032 		}
1033 	}
1034 
1035 	if (sta && !sta->sta.wme &&
1036 	    elems->wmm_info && local->hw.queues >= IEEE80211_NUM_ACS) {
1037 		sta->sta.wme = true;
1038 		ieee80211_check_fast_xmit(sta);
1039 	}
1040 
1041 	if (sta && elems->ht_operation && elems->ht_cap_elem &&
1042 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1043 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1044 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1045 		/* we both use HT */
1046 		struct ieee80211_ht_cap htcap_ie;
1047 		struct cfg80211_chan_def chandef;
1048 		enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth;
1049 
1050 		ieee80211_ht_oper_to_chandef(channel,
1051 					     elems->ht_operation,
1052 					     &chandef);
1053 
1054 		memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1055 		rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
1056 								   &htcap_ie,
1057 								   sta);
1058 
1059 		if (elems->vht_operation && elems->vht_cap_elem &&
1060 		    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20 &&
1061 		    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_40) {
1062 			/* we both use VHT */
1063 			struct ieee80211_vht_cap cap_ie;
1064 			struct ieee80211_sta_vht_cap cap = sta->sta.vht_cap;
1065 
1066 			ieee80211_vht_oper_to_chandef(channel,
1067 						      elems->vht_operation,
1068 						      &chandef);
1069 			memcpy(&cap_ie, elems->vht_cap_elem, sizeof(cap_ie));
1070 			ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
1071 							    &cap_ie, sta);
1072 			if (memcmp(&cap, &sta->sta.vht_cap, sizeof(cap)))
1073 				rates_updated |= true;
1074 		}
1075 
1076 		if (bw != sta->sta.bandwidth)
1077 			rates_updated |= true;
1078 
1079 		if (!cfg80211_chandef_compatible(&sdata->u.ibss.chandef,
1080 						 &chandef))
1081 			WARN_ON_ONCE(1);
1082 	}
1083 
1084 	if (sta && rates_updated) {
1085 		u32 changed = IEEE80211_RC_SUPP_RATES_CHANGED;
1086 		u8 rx_nss = sta->sta.rx_nss;
1087 
1088 		/* Force rx_nss recalculation */
1089 		sta->sta.rx_nss = 0;
1090 		rate_control_rate_init(sta);
1091 		if (sta->sta.rx_nss != rx_nss)
1092 			changed |= IEEE80211_RC_NSS_CHANGED;
1093 
1094 		drv_sta_rc_update(local, sdata, &sta->sta, changed);
1095 	}
1096 
1097 	rcu_read_unlock();
1098 }
1099 
1100 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
1101 				  struct ieee80211_mgmt *mgmt, size_t len,
1102 				  struct ieee80211_rx_status *rx_status,
1103 				  struct ieee802_11_elems *elems)
1104 {
1105 	struct ieee80211_local *local = sdata->local;
1106 	struct cfg80211_bss *cbss;
1107 	struct ieee80211_bss *bss;
1108 	struct ieee80211_channel *channel;
1109 	u64 beacon_timestamp, rx_timestamp;
1110 	u32 supp_rates = 0;
1111 	enum ieee80211_band band = rx_status->band;
1112 
1113 	channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
1114 	if (!channel)
1115 		return;
1116 
1117 	ieee80211_update_sta_info(sdata, mgmt, len, rx_status, elems, channel);
1118 
1119 	bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
1120 					channel);
1121 	if (!bss)
1122 		return;
1123 
1124 	cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1125 
1126 	/* same for beacon and probe response */
1127 	beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1128 
1129 	/* check if we need to merge IBSS */
1130 
1131 	/* not an IBSS */
1132 	if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1133 		goto put_bss;
1134 
1135 	/* different channel */
1136 	if (sdata->u.ibss.fixed_channel &&
1137 	    sdata->u.ibss.chandef.chan != cbss->channel)
1138 		goto put_bss;
1139 
1140 	/* different SSID */
1141 	if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1142 	    memcmp(elems->ssid, sdata->u.ibss.ssid,
1143 				sdata->u.ibss.ssid_len))
1144 		goto put_bss;
1145 
1146 	/* process channel switch */
1147 	if (sdata->vif.csa_active ||
1148 	    ieee80211_ibss_process_chanswitch(sdata, elems, true))
1149 		goto put_bss;
1150 
1151 	/* same BSSID */
1152 	if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1153 		goto put_bss;
1154 
1155 	/* we use a fixed BSSID */
1156 	if (sdata->u.ibss.fixed_bssid)
1157 		goto put_bss;
1158 
1159 	if (ieee80211_have_rx_timestamp(rx_status)) {
1160 		/* time when timestamp field was received */
1161 		rx_timestamp =
1162 			ieee80211_calculate_rx_timestamp(local, rx_status,
1163 							 len + FCS_LEN, 24);
1164 	} else {
1165 		/*
1166 		 * second best option: get current TSF
1167 		 * (will return -1 if not supported)
1168 		 */
1169 		rx_timestamp = drv_get_tsf(local, sdata);
1170 	}
1171 
1172 	ibss_dbg(sdata,
1173 		 "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
1174 		 mgmt->sa, mgmt->bssid,
1175 		 (unsigned long long)rx_timestamp,
1176 		 (unsigned long long)beacon_timestamp,
1177 		 (unsigned long long)(rx_timestamp - beacon_timestamp),
1178 		 jiffies);
1179 
1180 	if (beacon_timestamp > rx_timestamp) {
1181 		ibss_dbg(sdata,
1182 			 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1183 			 mgmt->bssid);
1184 		ieee80211_sta_join_ibss(sdata, bss);
1185 		supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1186 		ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1187 				       supp_rates);
1188 		rcu_read_unlock();
1189 	}
1190 
1191  put_bss:
1192 	ieee80211_rx_bss_put(local, bss);
1193 }
1194 
1195 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1196 			      const u8 *bssid, const u8 *addr,
1197 			      u32 supp_rates)
1198 {
1199 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1200 	struct ieee80211_local *local = sdata->local;
1201 	struct sta_info *sta;
1202 	struct ieee80211_chanctx_conf *chanctx_conf;
1203 	struct ieee80211_supported_band *sband;
1204 	enum nl80211_bss_scan_width scan_width;
1205 	int band;
1206 
1207 	/*
1208 	 * XXX: Consider removing the least recently used entry and
1209 	 * 	allow new one to be added.
1210 	 */
1211 	if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1212 		net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1213 				    sdata->name, addr);
1214 		return;
1215 	}
1216 
1217 	if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1218 		return;
1219 
1220 	if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1221 		return;
1222 
1223 	rcu_read_lock();
1224 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1225 	if (WARN_ON_ONCE(!chanctx_conf)) {
1226 		rcu_read_unlock();
1227 		return;
1228 	}
1229 	band = chanctx_conf->def.chan->band;
1230 	scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1231 	rcu_read_unlock();
1232 
1233 	sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1234 	if (!sta)
1235 		return;
1236 
1237 	sta->last_rx = jiffies;
1238 
1239 	/* make sure mandatory rates are always added */
1240 	sband = local->hw.wiphy->bands[band];
1241 	sta->sta.supp_rates[band] = supp_rates |
1242 			ieee80211_mandatory_rates(sband, scan_width);
1243 
1244 	spin_lock(&ifibss->incomplete_lock);
1245 	list_add(&sta->list, &ifibss->incomplete_stations);
1246 	spin_unlock(&ifibss->incomplete_lock);
1247 	ieee80211_queue_work(&local->hw, &sdata->work);
1248 }
1249 
1250 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1251 {
1252 	struct ieee80211_local *local = sdata->local;
1253 	struct sta_info *sta, *tmp;
1254 	unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1255 	unsigned long exp_rsn_time = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1256 
1257 	mutex_lock(&local->sta_mtx);
1258 
1259 	list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1260 		if (sdata != sta->sdata)
1261 			continue;
1262 
1263 		if (time_after(jiffies, sta->last_rx + exp_time) ||
1264 		    (time_after(jiffies, sta->last_rx + exp_rsn_time) &&
1265 		     sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1266 			sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1267 				sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1268 				"not authorized " : "", sta->sta.addr);
1269 
1270 			WARN_ON(__sta_info_destroy(sta));
1271 		}
1272 	}
1273 
1274 	mutex_unlock(&local->sta_mtx);
1275 }
1276 
1277 /*
1278  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1279  */
1280 
1281 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1282 {
1283 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1284 	enum nl80211_bss_scan_width scan_width;
1285 
1286 	sdata_assert_lock(sdata);
1287 
1288 	mod_timer(&ifibss->timer,
1289 		  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1290 
1291 	ieee80211_ibss_sta_expire(sdata);
1292 
1293 	if (time_before(jiffies, ifibss->last_scan_completed +
1294 		       IEEE80211_IBSS_MERGE_INTERVAL))
1295 		return;
1296 
1297 	if (ieee80211_sta_active_ibss(sdata))
1298 		return;
1299 
1300 	if (ifibss->fixed_channel)
1301 		return;
1302 
1303 	sdata_info(sdata,
1304 		   "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1305 
1306 	scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1307 	ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1308 				    NULL, 0, scan_width);
1309 }
1310 
1311 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1312 {
1313 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1314 	u8 bssid[ETH_ALEN];
1315 	u16 capability;
1316 	int i;
1317 
1318 	sdata_assert_lock(sdata);
1319 
1320 	if (ifibss->fixed_bssid) {
1321 		memcpy(bssid, ifibss->bssid, ETH_ALEN);
1322 	} else {
1323 		/* Generate random, not broadcast, locally administered BSSID. Mix in
1324 		 * own MAC address to make sure that devices that do not have proper
1325 		 * random number generator get different BSSID. */
1326 		get_random_bytes(bssid, ETH_ALEN);
1327 		for (i = 0; i < ETH_ALEN; i++)
1328 			bssid[i] ^= sdata->vif.addr[i];
1329 		bssid[0] &= ~0x01;
1330 		bssid[0] |= 0x02;
1331 	}
1332 
1333 	sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1334 
1335 	capability = WLAN_CAPABILITY_IBSS;
1336 
1337 	if (ifibss->privacy)
1338 		capability |= WLAN_CAPABILITY_PRIVACY;
1339 
1340 	__ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1341 				  &ifibss->chandef, ifibss->basic_rates,
1342 				  capability, 0, true);
1343 }
1344 
1345 static unsigned ibss_setup_channels(struct wiphy *wiphy,
1346 				    struct ieee80211_channel **channels,
1347 				    unsigned int channels_max,
1348 				    u32 center_freq, u32 width)
1349 {
1350 	struct ieee80211_channel *chan = NULL;
1351 	unsigned int n_chan = 0;
1352 	u32 start_freq, end_freq, freq;
1353 
1354 	if (width <= 20) {
1355 		start_freq = center_freq;
1356 		end_freq = center_freq;
1357 	} else {
1358 		start_freq = center_freq - width / 2 + 10;
1359 		end_freq = center_freq + width / 2 - 10;
1360 	}
1361 
1362 	for (freq = start_freq; freq <= end_freq; freq += 20) {
1363 		chan = ieee80211_get_channel(wiphy, freq);
1364 		if (!chan)
1365 			continue;
1366 		if (n_chan >= channels_max)
1367 			return n_chan;
1368 
1369 		channels[n_chan] = chan;
1370 		n_chan++;
1371 	}
1372 
1373 	return n_chan;
1374 }
1375 
1376 static unsigned int
1377 ieee80211_ibss_setup_scan_channels(struct wiphy *wiphy,
1378 				   const struct cfg80211_chan_def *chandef,
1379 				   struct ieee80211_channel **channels,
1380 				   unsigned int channels_max)
1381 {
1382 	unsigned int n_chan = 0;
1383 	u32 width, cf1, cf2 = 0;
1384 
1385 	switch (chandef->width) {
1386 	case NL80211_CHAN_WIDTH_40:
1387 		width = 40;
1388 		break;
1389 	case NL80211_CHAN_WIDTH_80P80:
1390 		cf2 = chandef->center_freq2;
1391 		/* fall through */
1392 	case NL80211_CHAN_WIDTH_80:
1393 		width = 80;
1394 		break;
1395 	case NL80211_CHAN_WIDTH_160:
1396 		width = 160;
1397 		break;
1398 	default:
1399 		width = 20;
1400 		break;
1401 	}
1402 
1403 	cf1 = chandef->center_freq1;
1404 
1405 	n_chan = ibss_setup_channels(wiphy, channels, channels_max, cf1, width);
1406 
1407 	if (cf2)
1408 		n_chan += ibss_setup_channels(wiphy, &channels[n_chan],
1409 					      channels_max - n_chan, cf2,
1410 					      width);
1411 
1412 	return n_chan;
1413 }
1414 
1415 /*
1416  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1417  */
1418 
1419 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1420 {
1421 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1422 	struct ieee80211_local *local = sdata->local;
1423 	struct cfg80211_bss *cbss;
1424 	struct ieee80211_channel *chan = NULL;
1425 	const u8 *bssid = NULL;
1426 	enum nl80211_bss_scan_width scan_width;
1427 	int active_ibss;
1428 
1429 	sdata_assert_lock(sdata);
1430 
1431 	active_ibss = ieee80211_sta_active_ibss(sdata);
1432 	ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1433 
1434 	if (active_ibss)
1435 		return;
1436 
1437 	if (ifibss->fixed_bssid)
1438 		bssid = ifibss->bssid;
1439 	if (ifibss->fixed_channel)
1440 		chan = ifibss->chandef.chan;
1441 	if (!is_zero_ether_addr(ifibss->bssid))
1442 		bssid = ifibss->bssid;
1443 	cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1444 				ifibss->ssid, ifibss->ssid_len,
1445 				IEEE80211_BSS_TYPE_IBSS,
1446 				IEEE80211_PRIVACY(ifibss->privacy));
1447 
1448 	if (cbss) {
1449 		struct ieee80211_bss *bss;
1450 
1451 		bss = (void *)cbss->priv;
1452 		ibss_dbg(sdata,
1453 			 "sta_find_ibss: selected %pM current %pM\n",
1454 			 cbss->bssid, ifibss->bssid);
1455 		sdata_info(sdata,
1456 			   "Selected IBSS BSSID %pM based on configured SSID\n",
1457 			   cbss->bssid);
1458 
1459 		ieee80211_sta_join_ibss(sdata, bss);
1460 		ieee80211_rx_bss_put(local, bss);
1461 		return;
1462 	}
1463 
1464 	/* if a fixed bssid and a fixed freq have been provided create the IBSS
1465 	 * directly and do not waste time scanning
1466 	 */
1467 	if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1468 		sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1469 			   bssid);
1470 		ieee80211_sta_create_ibss(sdata);
1471 		return;
1472 	}
1473 
1474 
1475 	ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1476 
1477 	/* Selected IBSS not found in current scan results - try to scan */
1478 	if (time_after(jiffies, ifibss->last_scan_completed +
1479 					IEEE80211_SCAN_INTERVAL)) {
1480 		struct ieee80211_channel *channels[8];
1481 		unsigned int num;
1482 
1483 		sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1484 
1485 		num = ieee80211_ibss_setup_scan_channels(local->hw.wiphy,
1486 							 &ifibss->chandef,
1487 							 channels,
1488 							 ARRAY_SIZE(channels));
1489 		scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1490 		ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1491 					    ifibss->ssid_len, channels, num,
1492 					    scan_width);
1493 	} else {
1494 		int interval = IEEE80211_SCAN_INTERVAL;
1495 
1496 		if (time_after(jiffies, ifibss->ibss_join_req +
1497 			       IEEE80211_IBSS_JOIN_TIMEOUT))
1498 			ieee80211_sta_create_ibss(sdata);
1499 
1500 		mod_timer(&ifibss->timer,
1501 			  round_jiffies(jiffies + interval));
1502 	}
1503 }
1504 
1505 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1506 					struct sk_buff *req)
1507 {
1508 	struct ieee80211_mgmt *mgmt = (void *)req->data;
1509 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1510 	struct ieee80211_local *local = sdata->local;
1511 	int tx_last_beacon, len = req->len;
1512 	struct sk_buff *skb;
1513 	struct beacon_data *presp;
1514 	u8 *pos, *end;
1515 
1516 	sdata_assert_lock(sdata);
1517 
1518 	presp = rcu_dereference_protected(ifibss->presp,
1519 					  lockdep_is_held(&sdata->wdev.mtx));
1520 
1521 	if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1522 	    len < 24 + 2 || !presp)
1523 		return;
1524 
1525 	tx_last_beacon = drv_tx_last_beacon(local);
1526 
1527 	ibss_dbg(sdata,
1528 		 "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
1529 		 mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
1530 
1531 	if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1532 		return;
1533 
1534 	if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1535 	    !is_broadcast_ether_addr(mgmt->bssid))
1536 		return;
1537 
1538 	end = ((u8 *) mgmt) + len;
1539 	pos = mgmt->u.probe_req.variable;
1540 	if (pos[0] != WLAN_EID_SSID ||
1541 	    pos + 2 + pos[1] > end) {
1542 		ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1543 			 mgmt->sa);
1544 		return;
1545 	}
1546 	if (pos[1] != 0 &&
1547 	    (pos[1] != ifibss->ssid_len ||
1548 	     memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1549 		/* Ignore ProbeReq for foreign SSID */
1550 		return;
1551 	}
1552 
1553 	/* Reply with ProbeResp */
1554 	skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1555 	if (!skb)
1556 		return;
1557 
1558 	skb_reserve(skb, local->tx_headroom);
1559 	memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
1560 
1561 	memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1562 	ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1563 	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1564 
1565 	/* avoid excessive retries for probe request to wildcard SSIDs */
1566 	if (pos[1] == 0)
1567 		IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1568 
1569 	ieee80211_tx_skb(sdata, skb);
1570 }
1571 
1572 static
1573 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1574 				    struct ieee80211_mgmt *mgmt, size_t len,
1575 				    struct ieee80211_rx_status *rx_status)
1576 {
1577 	size_t baselen;
1578 	struct ieee802_11_elems elems;
1579 
1580 	BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1581 		     offsetof(typeof(mgmt->u.beacon), variable));
1582 
1583 	/*
1584 	 * either beacon or probe_resp but the variable field is at the
1585 	 * same offset
1586 	 */
1587 	baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1588 	if (baselen > len)
1589 		return;
1590 
1591 	ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1592 			       false, &elems);
1593 
1594 	ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1595 }
1596 
1597 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1598 				   struct sk_buff *skb)
1599 {
1600 	struct ieee80211_rx_status *rx_status;
1601 	struct ieee80211_mgmt *mgmt;
1602 	u16 fc;
1603 	struct ieee802_11_elems elems;
1604 	int ies_len;
1605 
1606 	rx_status = IEEE80211_SKB_RXCB(skb);
1607 	mgmt = (struct ieee80211_mgmt *) skb->data;
1608 	fc = le16_to_cpu(mgmt->frame_control);
1609 
1610 	sdata_lock(sdata);
1611 
1612 	if (!sdata->u.ibss.ssid_len)
1613 		goto mgmt_out; /* not ready to merge yet */
1614 
1615 	switch (fc & IEEE80211_FCTL_STYPE) {
1616 	case IEEE80211_STYPE_PROBE_REQ:
1617 		ieee80211_rx_mgmt_probe_req(sdata, skb);
1618 		break;
1619 	case IEEE80211_STYPE_PROBE_RESP:
1620 	case IEEE80211_STYPE_BEACON:
1621 		ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1622 					       rx_status);
1623 		break;
1624 	case IEEE80211_STYPE_AUTH:
1625 		ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1626 		break;
1627 	case IEEE80211_STYPE_DEAUTH:
1628 		ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1629 		break;
1630 	case IEEE80211_STYPE_ACTION:
1631 		switch (mgmt->u.action.category) {
1632 		case WLAN_CATEGORY_SPECTRUM_MGMT:
1633 			ies_len = skb->len -
1634 				  offsetof(struct ieee80211_mgmt,
1635 					   u.action.u.chan_switch.variable);
1636 
1637 			if (ies_len < 0)
1638 				break;
1639 
1640 			ieee802_11_parse_elems(
1641 				mgmt->u.action.u.chan_switch.variable,
1642 				ies_len, true, &elems);
1643 
1644 			if (elems.parse_error)
1645 				break;
1646 
1647 			ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1648 							rx_status, &elems);
1649 			break;
1650 		}
1651 	}
1652 
1653  mgmt_out:
1654 	sdata_unlock(sdata);
1655 }
1656 
1657 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1658 {
1659 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1660 	struct sta_info *sta;
1661 
1662 	sdata_lock(sdata);
1663 
1664 	/*
1665 	 * Work could be scheduled after scan or similar
1666 	 * when we aren't even joined (or trying) with a
1667 	 * network.
1668 	 */
1669 	if (!ifibss->ssid_len)
1670 		goto out;
1671 
1672 	spin_lock_bh(&ifibss->incomplete_lock);
1673 	while (!list_empty(&ifibss->incomplete_stations)) {
1674 		sta = list_first_entry(&ifibss->incomplete_stations,
1675 				       struct sta_info, list);
1676 		list_del(&sta->list);
1677 		spin_unlock_bh(&ifibss->incomplete_lock);
1678 
1679 		ieee80211_ibss_finish_sta(sta);
1680 		rcu_read_unlock();
1681 		spin_lock_bh(&ifibss->incomplete_lock);
1682 	}
1683 	spin_unlock_bh(&ifibss->incomplete_lock);
1684 
1685 	switch (ifibss->state) {
1686 	case IEEE80211_IBSS_MLME_SEARCH:
1687 		ieee80211_sta_find_ibss(sdata);
1688 		break;
1689 	case IEEE80211_IBSS_MLME_JOINED:
1690 		ieee80211_sta_merge_ibss(sdata);
1691 		break;
1692 	default:
1693 		WARN_ON(1);
1694 		break;
1695 	}
1696 
1697  out:
1698 	sdata_unlock(sdata);
1699 }
1700 
1701 static void ieee80211_ibss_timer(unsigned long data)
1702 {
1703 	struct ieee80211_sub_if_data *sdata =
1704 		(struct ieee80211_sub_if_data *) data;
1705 
1706 	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1707 }
1708 
1709 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1710 {
1711 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1712 
1713 	setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1714 		    (unsigned long) sdata);
1715 	INIT_LIST_HEAD(&ifibss->incomplete_stations);
1716 	spin_lock_init(&ifibss->incomplete_lock);
1717 	INIT_WORK(&ifibss->csa_connection_drop_work,
1718 		  ieee80211_csa_connection_drop_work);
1719 }
1720 
1721 /* scan finished notification */
1722 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1723 {
1724 	struct ieee80211_sub_if_data *sdata;
1725 
1726 	mutex_lock(&local->iflist_mtx);
1727 	list_for_each_entry(sdata, &local->interfaces, list) {
1728 		if (!ieee80211_sdata_running(sdata))
1729 			continue;
1730 		if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1731 			continue;
1732 		sdata->u.ibss.last_scan_completed = jiffies;
1733 		ieee80211_queue_work(&local->hw, &sdata->work);
1734 	}
1735 	mutex_unlock(&local->iflist_mtx);
1736 }
1737 
1738 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1739 			struct cfg80211_ibss_params *params)
1740 {
1741 	u32 changed = 0;
1742 	u32 rate_flags;
1743 	struct ieee80211_supported_band *sband;
1744 	enum ieee80211_chanctx_mode chanmode;
1745 	struct ieee80211_local *local = sdata->local;
1746 	int radar_detect_width = 0;
1747 	int i;
1748 	int ret;
1749 
1750 	ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1751 					    &params->chandef,
1752 					    sdata->wdev.iftype);
1753 	if (ret < 0)
1754 		return ret;
1755 
1756 	if (ret > 0) {
1757 		if (!params->userspace_handles_dfs)
1758 			return -EINVAL;
1759 		radar_detect_width = BIT(params->chandef.width);
1760 	}
1761 
1762 	chanmode = (params->channel_fixed && !ret) ?
1763 		IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE;
1764 
1765 	mutex_lock(&local->chanctx_mtx);
1766 	ret = ieee80211_check_combinations(sdata, &params->chandef, chanmode,
1767 					   radar_detect_width);
1768 	mutex_unlock(&local->chanctx_mtx);
1769 	if (ret < 0)
1770 		return ret;
1771 
1772 	if (params->bssid) {
1773 		memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1774 		sdata->u.ibss.fixed_bssid = true;
1775 	} else
1776 		sdata->u.ibss.fixed_bssid = false;
1777 
1778 	sdata->u.ibss.privacy = params->privacy;
1779 	sdata->u.ibss.control_port = params->control_port;
1780 	sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1781 	sdata->u.ibss.basic_rates = params->basic_rates;
1782 	sdata->u.ibss.last_scan_completed = jiffies;
1783 
1784 	/* fix basic_rates if channel does not support these rates */
1785 	rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1786 	sband = local->hw.wiphy->bands[params->chandef.chan->band];
1787 	for (i = 0; i < sband->n_bitrates; i++) {
1788 		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1789 			sdata->u.ibss.basic_rates &= ~BIT(i);
1790 	}
1791 	memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1792 	       sizeof(params->mcast_rate));
1793 
1794 	sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1795 
1796 	sdata->u.ibss.chandef = params->chandef;
1797 	sdata->u.ibss.fixed_channel = params->channel_fixed;
1798 
1799 	if (params->ie) {
1800 		sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1801 					   GFP_KERNEL);
1802 		if (sdata->u.ibss.ie)
1803 			sdata->u.ibss.ie_len = params->ie_len;
1804 	}
1805 
1806 	sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1807 	sdata->u.ibss.ibss_join_req = jiffies;
1808 
1809 	memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1810 	sdata->u.ibss.ssid_len = params->ssid_len;
1811 
1812 	memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1813 	       sizeof(sdata->u.ibss.ht_capa));
1814 	memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1815 	       sizeof(sdata->u.ibss.ht_capa_mask));
1816 
1817 	/*
1818 	 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1819 	 * reserved, but an HT STA shall protect HT transmissions as though
1820 	 * the HT Protection field were set to non-HT mixed mode.
1821 	 *
1822 	 * In an IBSS, the RIFS Mode field of the HT Operation element is
1823 	 * also reserved, but an HT STA shall operate as though this field
1824 	 * were set to 1.
1825 	 */
1826 
1827 	sdata->vif.bss_conf.ht_operation_mode |=
1828 		  IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1829 		| IEEE80211_HT_PARAM_RIFS_MODE;
1830 
1831 	changed |= BSS_CHANGED_HT;
1832 	ieee80211_bss_info_change_notify(sdata, changed);
1833 
1834 	sdata->smps_mode = IEEE80211_SMPS_OFF;
1835 	sdata->needed_rx_chains = local->rx_chains;
1836 
1837 	ieee80211_queue_work(&local->hw, &sdata->work);
1838 
1839 	return 0;
1840 }
1841 
1842 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1843 {
1844 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1845 
1846 	ieee80211_ibss_disconnect(sdata);
1847 	ifibss->ssid_len = 0;
1848 	eth_zero_addr(ifibss->bssid);
1849 
1850 	/* remove beacon */
1851 	kfree(sdata->u.ibss.ie);
1852 
1853 	/* on the next join, re-program HT parameters */
1854 	memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1855 	memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1856 
1857 	synchronize_rcu();
1858 
1859 	skb_queue_purge(&sdata->skb_queue);
1860 
1861 	del_timer_sync(&sdata->u.ibss.timer);
1862 
1863 	return 0;
1864 }
1865