xref: /linux/net/mac80211/ibss.c (revision b24413180f5600bcb3bb70fbed5cf186b60864bd)
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  * Copyright(c) 2016 Intel Deutschland GmbH
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License version 2 as
14  * published by the Free Software Foundation.
15  */
16 
17 #include <linux/delay.h>
18 #include <linux/slab.h>
19 #include <linux/if_ether.h>
20 #include <linux/skbuff.h>
21 #include <linux/if_arp.h>
22 #include <linux/etherdevice.h>
23 #include <linux/rtnetlink.h>
24 #include <net/mac80211.h>
25 
26 #include "ieee80211_i.h"
27 #include "driver-ops.h"
28 #include "rate.h"
29 
30 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
31 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
32 
33 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
34 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
35 #define IEEE80211_IBSS_RSN_INACTIVITY_LIMIT (10 * HZ)
36 
37 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
38 
39 static struct beacon_data *
40 ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
41 			   const int beacon_int, const u32 basic_rates,
42 			   const u16 capability, u64 tsf,
43 			   struct cfg80211_chan_def *chandef,
44 			   bool *have_higher_than_11mbit,
45 			   struct cfg80211_csa_settings *csa_settings)
46 {
47 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
48 	struct ieee80211_local *local = sdata->local;
49 	int rates_n = 0, i, ri;
50 	struct ieee80211_mgmt *mgmt;
51 	u8 *pos;
52 	struct ieee80211_supported_band *sband;
53 	u32 rate_flags, rates = 0, rates_added = 0;
54 	struct beacon_data *presp;
55 	int frame_len;
56 	int shift;
57 
58 	/* Build IBSS probe response */
59 	frame_len = sizeof(struct ieee80211_hdr_3addr) +
60 		    12 /* struct ieee80211_mgmt.u.beacon */ +
61 		    2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
62 		    2 + 8 /* max Supported Rates */ +
63 		    3 /* max DS params */ +
64 		    4 /* IBSS params */ +
65 		    5 /* Channel Switch Announcement */ +
66 		    2 + (IEEE80211_MAX_SUPP_RATES - 8) +
67 		    2 + sizeof(struct ieee80211_ht_cap) +
68 		    2 + sizeof(struct ieee80211_ht_operation) +
69 		    2 + sizeof(struct ieee80211_vht_cap) +
70 		    2 + sizeof(struct ieee80211_vht_operation) +
71 		    ifibss->ie_len;
72 	presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
73 	if (!presp)
74 		return NULL;
75 
76 	presp->head = (void *)(presp + 1);
77 
78 	mgmt = (void *) presp->head;
79 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
80 					  IEEE80211_STYPE_PROBE_RESP);
81 	eth_broadcast_addr(mgmt->da);
82 	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
83 	memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
84 	mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
85 	mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
86 	mgmt->u.beacon.capab_info = cpu_to_le16(capability);
87 
88 	pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
89 
90 	*pos++ = WLAN_EID_SSID;
91 	*pos++ = ifibss->ssid_len;
92 	memcpy(pos, ifibss->ssid, ifibss->ssid_len);
93 	pos += ifibss->ssid_len;
94 
95 	sband = local->hw.wiphy->bands[chandef->chan->band];
96 	rate_flags = ieee80211_chandef_rate_flags(chandef);
97 	shift = ieee80211_chandef_get_shift(chandef);
98 	rates_n = 0;
99 	if (have_higher_than_11mbit)
100 		*have_higher_than_11mbit = false;
101 
102 	for (i = 0; i < sband->n_bitrates; i++) {
103 		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
104 			continue;
105 		if (sband->bitrates[i].bitrate > 110 &&
106 		    have_higher_than_11mbit)
107 			*have_higher_than_11mbit = true;
108 
109 		rates |= BIT(i);
110 		rates_n++;
111 	}
112 
113 	*pos++ = WLAN_EID_SUPP_RATES;
114 	*pos++ = min_t(int, 8, rates_n);
115 	for (ri = 0; ri < sband->n_bitrates; ri++) {
116 		int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
117 					5 * (1 << shift));
118 		u8 basic = 0;
119 		if (!(rates & BIT(ri)))
120 			continue;
121 
122 		if (basic_rates & BIT(ri))
123 			basic = 0x80;
124 		*pos++ = basic | (u8) rate;
125 		if (++rates_added == 8) {
126 			ri++; /* continue at next rate for EXT_SUPP_RATES */
127 			break;
128 		}
129 	}
130 
131 	if (sband->band == NL80211_BAND_2GHZ) {
132 		*pos++ = WLAN_EID_DS_PARAMS;
133 		*pos++ = 1;
134 		*pos++ = ieee80211_frequency_to_channel(
135 				chandef->chan->center_freq);
136 	}
137 
138 	*pos++ = WLAN_EID_IBSS_PARAMS;
139 	*pos++ = 2;
140 	/* FIX: set ATIM window based on scan results */
141 	*pos++ = 0;
142 	*pos++ = 0;
143 
144 	if (csa_settings) {
145 		*pos++ = WLAN_EID_CHANNEL_SWITCH;
146 		*pos++ = 3;
147 		*pos++ = csa_settings->block_tx ? 1 : 0;
148 		*pos++ = ieee80211_frequency_to_channel(
149 				csa_settings->chandef.chan->center_freq);
150 		presp->csa_counter_offsets[0] = (pos - presp->head);
151 		*pos++ = csa_settings->count;
152 		presp->csa_current_counter = csa_settings->count;
153 	}
154 
155 	/* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
156 	if (rates_n > 8) {
157 		*pos++ = WLAN_EID_EXT_SUPP_RATES;
158 		*pos++ = rates_n - 8;
159 		for (; ri < sband->n_bitrates; ri++) {
160 			int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
161 						5 * (1 << shift));
162 			u8 basic = 0;
163 			if (!(rates & BIT(ri)))
164 				continue;
165 
166 			if (basic_rates & BIT(ri))
167 				basic = 0x80;
168 			*pos++ = basic | (u8) rate;
169 		}
170 	}
171 
172 	if (ifibss->ie_len) {
173 		memcpy(pos, ifibss->ie, ifibss->ie_len);
174 		pos += ifibss->ie_len;
175 	}
176 
177 	/* add HT capability and information IEs */
178 	if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT &&
179 	    chandef->width != NL80211_CHAN_WIDTH_5 &&
180 	    chandef->width != NL80211_CHAN_WIDTH_10 &&
181 	    sband->ht_cap.ht_supported) {
182 		struct ieee80211_sta_ht_cap ht_cap;
183 
184 		memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
185 		ieee80211_apply_htcap_overrides(sdata, &ht_cap);
186 
187 		pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
188 		/*
189 		 * Note: According to 802.11n-2009 9.13.3.1, HT Protection
190 		 * field and RIFS Mode are reserved in IBSS mode, therefore
191 		 * keep them at 0
192 		 */
193 		pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
194 						 chandef, 0, false);
195 
196 		/* add VHT capability and information IEs */
197 		if (chandef->width != NL80211_CHAN_WIDTH_20 &&
198 		    chandef->width != NL80211_CHAN_WIDTH_40 &&
199 		    sband->vht_cap.vht_supported) {
200 			pos = ieee80211_ie_build_vht_cap(pos, &sband->vht_cap,
201 							 sband->vht_cap.cap);
202 			pos = ieee80211_ie_build_vht_oper(pos, &sband->vht_cap,
203 							  chandef);
204 		}
205 	}
206 
207 	if (local->hw.queues >= IEEE80211_NUM_ACS)
208 		pos = ieee80211_add_wmm_info_ie(pos, 0); /* U-APSD not in use */
209 
210 	presp->head_len = pos - presp->head;
211 	if (WARN_ON(presp->head_len > frame_len))
212 		goto error;
213 
214 	return presp;
215 error:
216 	kfree(presp);
217 	return NULL;
218 }
219 
220 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
221 				      const u8 *bssid, const int beacon_int,
222 				      struct cfg80211_chan_def *req_chandef,
223 				      const u32 basic_rates,
224 				      const u16 capability, u64 tsf,
225 				      bool creator)
226 {
227 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
228 	struct ieee80211_local *local = sdata->local;
229 	struct ieee80211_mgmt *mgmt;
230 	struct cfg80211_bss *bss;
231 	u32 bss_change;
232 	struct cfg80211_chan_def chandef;
233 	struct ieee80211_channel *chan;
234 	struct beacon_data *presp;
235 	struct cfg80211_inform_bss bss_meta = {};
236 	bool have_higher_than_11mbit;
237 	bool radar_required;
238 	int err;
239 
240 	sdata_assert_lock(sdata);
241 
242 	/* Reset own TSF to allow time synchronization work. */
243 	drv_reset_tsf(local, sdata);
244 
245 	if (!ether_addr_equal(ifibss->bssid, bssid))
246 		sta_info_flush(sdata);
247 
248 	/* if merging, indicate to driver that we leave the old IBSS */
249 	if (sdata->vif.bss_conf.ibss_joined) {
250 		sdata->vif.bss_conf.ibss_joined = false;
251 		sdata->vif.bss_conf.ibss_creator = false;
252 		sdata->vif.bss_conf.enable_beacon = false;
253 		netif_carrier_off(sdata->dev);
254 		ieee80211_bss_info_change_notify(sdata,
255 						 BSS_CHANGED_IBSS |
256 						 BSS_CHANGED_BEACON_ENABLED);
257 		drv_leave_ibss(local, sdata);
258 	}
259 
260 	presp = rcu_dereference_protected(ifibss->presp,
261 					  lockdep_is_held(&sdata->wdev.mtx));
262 	RCU_INIT_POINTER(ifibss->presp, NULL);
263 	if (presp)
264 		kfree_rcu(presp, rcu_head);
265 
266 	/* make a copy of the chandef, it could be modified below. */
267 	chandef = *req_chandef;
268 	chan = chandef.chan;
269 	if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
270 				     NL80211_IFTYPE_ADHOC)) {
271 		if (chandef.width == NL80211_CHAN_WIDTH_5 ||
272 		    chandef.width == NL80211_CHAN_WIDTH_10 ||
273 		    chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
274 		    chandef.width == NL80211_CHAN_WIDTH_20) {
275 			sdata_info(sdata,
276 				   "Failed to join IBSS, beacons forbidden\n");
277 			return;
278 		}
279 		chandef.width = NL80211_CHAN_WIDTH_20;
280 		chandef.center_freq1 = chan->center_freq;
281 		/* check again for downgraded chandef */
282 		if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
283 					     NL80211_IFTYPE_ADHOC)) {
284 			sdata_info(sdata,
285 				   "Failed to join IBSS, beacons forbidden\n");
286 			return;
287 		}
288 	}
289 
290 	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
291 					    &chandef, NL80211_IFTYPE_ADHOC);
292 	if (err < 0) {
293 		sdata_info(sdata,
294 			   "Failed to join IBSS, invalid chandef\n");
295 		return;
296 	}
297 	if (err > 0 && !ifibss->userspace_handles_dfs) {
298 		sdata_info(sdata,
299 			   "Failed to join IBSS, DFS channel without control program\n");
300 		return;
301 	}
302 
303 	radar_required = err;
304 
305 	mutex_lock(&local->mtx);
306 	if (ieee80211_vif_use_channel(sdata, &chandef,
307 				      ifibss->fixed_channel ?
308 					IEEE80211_CHANCTX_SHARED :
309 					IEEE80211_CHANCTX_EXCLUSIVE)) {
310 		sdata_info(sdata, "Failed to join IBSS, no channel context\n");
311 		mutex_unlock(&local->mtx);
312 		return;
313 	}
314 	sdata->radar_required = radar_required;
315 	mutex_unlock(&local->mtx);
316 
317 	memcpy(ifibss->bssid, bssid, ETH_ALEN);
318 
319 	presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
320 					   capability, tsf, &chandef,
321 					   &have_higher_than_11mbit, NULL);
322 	if (!presp)
323 		return;
324 
325 	rcu_assign_pointer(ifibss->presp, presp);
326 	mgmt = (void *)presp->head;
327 
328 	sdata->vif.bss_conf.enable_beacon = true;
329 	sdata->vif.bss_conf.beacon_int = beacon_int;
330 	sdata->vif.bss_conf.basic_rates = basic_rates;
331 	sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
332 	memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
333 	bss_change = BSS_CHANGED_BEACON_INT;
334 	bss_change |= ieee80211_reset_erp_info(sdata);
335 	bss_change |= BSS_CHANGED_BSSID;
336 	bss_change |= BSS_CHANGED_BEACON;
337 	bss_change |= BSS_CHANGED_BEACON_ENABLED;
338 	bss_change |= BSS_CHANGED_BASIC_RATES;
339 	bss_change |= BSS_CHANGED_HT;
340 	bss_change |= BSS_CHANGED_IBSS;
341 	bss_change |= BSS_CHANGED_SSID;
342 
343 	/*
344 	 * In 5 GHz/802.11a, we can always use short slot time.
345 	 * (IEEE 802.11-2012 18.3.8.7)
346 	 *
347 	 * In 2.4GHz, we must always use long slots in IBSS for compatibility
348 	 * reasons.
349 	 * (IEEE 802.11-2012 19.4.5)
350 	 *
351 	 * HT follows these specifications (IEEE 802.11-2012 20.3.18)
352 	 */
353 	sdata->vif.bss_conf.use_short_slot = chan->band == NL80211_BAND_5GHZ;
354 	bss_change |= BSS_CHANGED_ERP_SLOT;
355 
356 	/* cf. IEEE 802.11 9.2.12 */
357 	if (chan->band == NL80211_BAND_2GHZ && have_higher_than_11mbit)
358 		sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
359 	else
360 		sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
361 
362 	ieee80211_set_wmm_default(sdata, true, false);
363 
364 	sdata->vif.bss_conf.ibss_joined = true;
365 	sdata->vif.bss_conf.ibss_creator = creator;
366 
367 	err = drv_join_ibss(local, sdata);
368 	if (err) {
369 		sdata->vif.bss_conf.ibss_joined = false;
370 		sdata->vif.bss_conf.ibss_creator = false;
371 		sdata->vif.bss_conf.enable_beacon = false;
372 		sdata->vif.bss_conf.ssid_len = 0;
373 		RCU_INIT_POINTER(ifibss->presp, NULL);
374 		kfree_rcu(presp, rcu_head);
375 		mutex_lock(&local->mtx);
376 		ieee80211_vif_release_channel(sdata);
377 		mutex_unlock(&local->mtx);
378 		sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
379 			   err);
380 		return;
381 	}
382 
383 	ieee80211_bss_info_change_notify(sdata, bss_change);
384 
385 	ifibss->state = IEEE80211_IBSS_MLME_JOINED;
386 	mod_timer(&ifibss->timer,
387 		  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
388 
389 	bss_meta.chan = chan;
390 	bss_meta.scan_width = cfg80211_chandef_to_scan_width(&chandef);
391 	bss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta, mgmt,
392 					     presp->head_len, GFP_KERNEL);
393 
394 	cfg80211_put_bss(local->hw.wiphy, bss);
395 	netif_carrier_on(sdata->dev);
396 	cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
397 }
398 
399 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
400 				    struct ieee80211_bss *bss)
401 {
402 	struct cfg80211_bss *cbss =
403 		container_of((void *)bss, struct cfg80211_bss, priv);
404 	struct ieee80211_supported_band *sband;
405 	struct cfg80211_chan_def chandef;
406 	u32 basic_rates;
407 	int i, j;
408 	u16 beacon_int = cbss->beacon_interval;
409 	const struct cfg80211_bss_ies *ies;
410 	enum nl80211_channel_type chan_type;
411 	u64 tsf;
412 	u32 rate_flags;
413 	int shift;
414 
415 	sdata_assert_lock(sdata);
416 
417 	if (beacon_int < 10)
418 		beacon_int = 10;
419 
420 	switch (sdata->u.ibss.chandef.width) {
421 	case NL80211_CHAN_WIDTH_20_NOHT:
422 	case NL80211_CHAN_WIDTH_20:
423 	case NL80211_CHAN_WIDTH_40:
424 		chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
425 		cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
426 		break;
427 	case NL80211_CHAN_WIDTH_5:
428 	case NL80211_CHAN_WIDTH_10:
429 		cfg80211_chandef_create(&chandef, cbss->channel,
430 					NL80211_CHAN_NO_HT);
431 		chandef.width = sdata->u.ibss.chandef.width;
432 		break;
433 	case NL80211_CHAN_WIDTH_80:
434 	case NL80211_CHAN_WIDTH_80P80:
435 	case NL80211_CHAN_WIDTH_160:
436 		chandef = sdata->u.ibss.chandef;
437 		chandef.chan = cbss->channel;
438 		break;
439 	default:
440 		/* fall back to 20 MHz for unsupported modes */
441 		cfg80211_chandef_create(&chandef, cbss->channel,
442 					NL80211_CHAN_NO_HT);
443 		break;
444 	}
445 
446 	sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
447 	rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
448 	shift = ieee80211_vif_get_shift(&sdata->vif);
449 
450 	basic_rates = 0;
451 
452 	for (i = 0; i < bss->supp_rates_len; i++) {
453 		int rate = bss->supp_rates[i] & 0x7f;
454 		bool is_basic = !!(bss->supp_rates[i] & 0x80);
455 
456 		for (j = 0; j < sband->n_bitrates; j++) {
457 			int brate;
458 			if ((rate_flags & sband->bitrates[j].flags)
459 			    != rate_flags)
460 				continue;
461 
462 			brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
463 					     5 * (1 << shift));
464 			if (brate == rate) {
465 				if (is_basic)
466 					basic_rates |= BIT(j);
467 				break;
468 			}
469 		}
470 	}
471 
472 	rcu_read_lock();
473 	ies = rcu_dereference(cbss->ies);
474 	tsf = ies->tsf;
475 	rcu_read_unlock();
476 
477 	__ieee80211_sta_join_ibss(sdata, cbss->bssid,
478 				  beacon_int,
479 				  &chandef,
480 				  basic_rates,
481 				  cbss->capability,
482 				  tsf, false);
483 }
484 
485 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
486 			      struct cfg80211_csa_settings *csa_settings)
487 {
488 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
489 	struct beacon_data *presp, *old_presp;
490 	struct cfg80211_bss *cbss;
491 	const struct cfg80211_bss_ies *ies;
492 	u16 capability = WLAN_CAPABILITY_IBSS;
493 	u64 tsf;
494 	int ret = 0;
495 
496 	sdata_assert_lock(sdata);
497 
498 	if (ifibss->privacy)
499 		capability |= WLAN_CAPABILITY_PRIVACY;
500 
501 	cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
502 				ifibss->bssid, ifibss->ssid,
503 				ifibss->ssid_len, IEEE80211_BSS_TYPE_IBSS,
504 				IEEE80211_PRIVACY(ifibss->privacy));
505 
506 	if (WARN_ON(!cbss)) {
507 		ret = -EINVAL;
508 		goto out;
509 	}
510 
511 	rcu_read_lock();
512 	ies = rcu_dereference(cbss->ies);
513 	tsf = ies->tsf;
514 	rcu_read_unlock();
515 	cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
516 
517 	old_presp = rcu_dereference_protected(ifibss->presp,
518 					  lockdep_is_held(&sdata->wdev.mtx));
519 
520 	presp = ieee80211_ibss_build_presp(sdata,
521 					   sdata->vif.bss_conf.beacon_int,
522 					   sdata->vif.bss_conf.basic_rates,
523 					   capability, tsf, &ifibss->chandef,
524 					   NULL, csa_settings);
525 	if (!presp) {
526 		ret = -ENOMEM;
527 		goto out;
528 	}
529 
530 	rcu_assign_pointer(ifibss->presp, presp);
531 	if (old_presp)
532 		kfree_rcu(old_presp, rcu_head);
533 
534 	return BSS_CHANGED_BEACON;
535  out:
536 	return ret;
537 }
538 
539 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
540 {
541 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
542 	struct cfg80211_bss *cbss;
543 	int err, changed = 0;
544 
545 	sdata_assert_lock(sdata);
546 
547 	/* update cfg80211 bss information with the new channel */
548 	if (!is_zero_ether_addr(ifibss->bssid)) {
549 		cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
550 					ifibss->chandef.chan,
551 					ifibss->bssid, ifibss->ssid,
552 					ifibss->ssid_len,
553 					IEEE80211_BSS_TYPE_IBSS,
554 					IEEE80211_PRIVACY(ifibss->privacy));
555 		/* XXX: should not really modify cfg80211 data */
556 		if (cbss) {
557 			cbss->channel = sdata->csa_chandef.chan;
558 			cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
559 		}
560 	}
561 
562 	ifibss->chandef = sdata->csa_chandef;
563 
564 	/* generate the beacon */
565 	err = ieee80211_ibss_csa_beacon(sdata, NULL);
566 	if (err < 0)
567 		return err;
568 
569 	changed |= err;
570 
571 	return changed;
572 }
573 
574 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
575 {
576 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
577 
578 	cancel_work_sync(&ifibss->csa_connection_drop_work);
579 }
580 
581 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
582 	__acquires(RCU)
583 {
584 	struct ieee80211_sub_if_data *sdata = sta->sdata;
585 	u8 addr[ETH_ALEN];
586 
587 	memcpy(addr, sta->sta.addr, ETH_ALEN);
588 
589 	ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
590 
591 	sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
592 	sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
593 	/* authorize the station only if the network is not RSN protected. If
594 	 * not wait for the userspace to authorize it */
595 	if (!sta->sdata->u.ibss.control_port)
596 		sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
597 
598 	rate_control_rate_init(sta);
599 
600 	/* If it fails, maybe we raced another insertion? */
601 	if (sta_info_insert_rcu(sta))
602 		return sta_info_get(sdata, addr);
603 	return sta;
604 }
605 
606 static struct sta_info *
607 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
608 		       const u8 *addr, u32 supp_rates)
609 	__acquires(RCU)
610 {
611 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
612 	struct ieee80211_local *local = sdata->local;
613 	struct sta_info *sta;
614 	struct ieee80211_chanctx_conf *chanctx_conf;
615 	struct ieee80211_supported_band *sband;
616 	enum nl80211_bss_scan_width scan_width;
617 	int band;
618 
619 	/*
620 	 * XXX: Consider removing the least recently used entry and
621 	 * 	allow new one to be added.
622 	 */
623 	if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
624 		net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
625 				    sdata->name, addr);
626 		rcu_read_lock();
627 		return NULL;
628 	}
629 
630 	if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
631 		rcu_read_lock();
632 		return NULL;
633 	}
634 
635 	if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
636 		rcu_read_lock();
637 		return NULL;
638 	}
639 
640 	rcu_read_lock();
641 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
642 	if (WARN_ON_ONCE(!chanctx_conf))
643 		return NULL;
644 	band = chanctx_conf->def.chan->band;
645 	scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
646 	rcu_read_unlock();
647 
648 	sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
649 	if (!sta) {
650 		rcu_read_lock();
651 		return NULL;
652 	}
653 
654 	/* make sure mandatory rates are always added */
655 	sband = local->hw.wiphy->bands[band];
656 	sta->sta.supp_rates[band] = supp_rates |
657 			ieee80211_mandatory_rates(sband, scan_width);
658 
659 	return ieee80211_ibss_finish_sta(sta);
660 }
661 
662 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
663 {
664 	struct ieee80211_local *local = sdata->local;
665 	int active = 0;
666 	struct sta_info *sta;
667 
668 	sdata_assert_lock(sdata);
669 
670 	rcu_read_lock();
671 
672 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
673 		unsigned long last_active = ieee80211_sta_last_active(sta);
674 
675 		if (sta->sdata == sdata &&
676 		    time_is_after_jiffies(last_active +
677 					  IEEE80211_IBSS_MERGE_INTERVAL)) {
678 			active++;
679 			break;
680 		}
681 	}
682 
683 	rcu_read_unlock();
684 
685 	return active;
686 }
687 
688 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
689 {
690 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
691 	struct ieee80211_local *local = sdata->local;
692 	struct cfg80211_bss *cbss;
693 	struct beacon_data *presp;
694 	struct sta_info *sta;
695 
696 	if (!is_zero_ether_addr(ifibss->bssid)) {
697 		cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
698 					ifibss->bssid, ifibss->ssid,
699 					ifibss->ssid_len,
700 					IEEE80211_BSS_TYPE_IBSS,
701 					IEEE80211_PRIVACY(ifibss->privacy));
702 
703 		if (cbss) {
704 			cfg80211_unlink_bss(local->hw.wiphy, cbss);
705 			cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
706 		}
707 	}
708 
709 	ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
710 
711 	sta_info_flush(sdata);
712 
713 	spin_lock_bh(&ifibss->incomplete_lock);
714 	while (!list_empty(&ifibss->incomplete_stations)) {
715 		sta = list_first_entry(&ifibss->incomplete_stations,
716 				       struct sta_info, list);
717 		list_del(&sta->list);
718 		spin_unlock_bh(&ifibss->incomplete_lock);
719 
720 		sta_info_free(local, sta);
721 		spin_lock_bh(&ifibss->incomplete_lock);
722 	}
723 	spin_unlock_bh(&ifibss->incomplete_lock);
724 
725 	netif_carrier_off(sdata->dev);
726 
727 	sdata->vif.bss_conf.ibss_joined = false;
728 	sdata->vif.bss_conf.ibss_creator = false;
729 	sdata->vif.bss_conf.enable_beacon = false;
730 	sdata->vif.bss_conf.ssid_len = 0;
731 
732 	/* remove beacon */
733 	presp = rcu_dereference_protected(ifibss->presp,
734 					  lockdep_is_held(&sdata->wdev.mtx));
735 	RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
736 	if (presp)
737 		kfree_rcu(presp, rcu_head);
738 
739 	clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
740 	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
741 						BSS_CHANGED_IBSS);
742 	drv_leave_ibss(local, sdata);
743 	mutex_lock(&local->mtx);
744 	ieee80211_vif_release_channel(sdata);
745 	mutex_unlock(&local->mtx);
746 }
747 
748 static void ieee80211_csa_connection_drop_work(struct work_struct *work)
749 {
750 	struct ieee80211_sub_if_data *sdata =
751 		container_of(work, struct ieee80211_sub_if_data,
752 			     u.ibss.csa_connection_drop_work);
753 
754 	sdata_lock(sdata);
755 
756 	ieee80211_ibss_disconnect(sdata);
757 	synchronize_rcu();
758 	skb_queue_purge(&sdata->skb_queue);
759 
760 	/* trigger a scan to find another IBSS network to join */
761 	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
762 
763 	sdata_unlock(sdata);
764 }
765 
766 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
767 {
768 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
769 	int err;
770 
771 	/* if the current channel is a DFS channel, mark the channel as
772 	 * unavailable.
773 	 */
774 	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
775 					    &ifibss->chandef,
776 					    NL80211_IFTYPE_ADHOC);
777 	if (err > 0)
778 		cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
779 				     GFP_ATOMIC);
780 }
781 
782 static bool
783 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
784 				  struct ieee802_11_elems *elems,
785 				  bool beacon)
786 {
787 	struct cfg80211_csa_settings params;
788 	struct ieee80211_csa_ie csa_ie;
789 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
790 	enum nl80211_channel_type ch_type;
791 	int err;
792 	u32 sta_flags;
793 
794 	sdata_assert_lock(sdata);
795 
796 	sta_flags = IEEE80211_STA_DISABLE_VHT;
797 	switch (ifibss->chandef.width) {
798 	case NL80211_CHAN_WIDTH_5:
799 	case NL80211_CHAN_WIDTH_10:
800 	case NL80211_CHAN_WIDTH_20_NOHT:
801 		sta_flags |= IEEE80211_STA_DISABLE_HT;
802 		/* fall through */
803 	case NL80211_CHAN_WIDTH_20:
804 		sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
805 		break;
806 	default:
807 		break;
808 	}
809 
810 	memset(&params, 0, sizeof(params));
811 	err = ieee80211_parse_ch_switch_ie(sdata, elems,
812 					   ifibss->chandef.chan->band,
813 					   sta_flags, ifibss->bssid, &csa_ie);
814 	/* can't switch to destination channel, fail */
815 	if (err < 0)
816 		goto disconnect;
817 
818 	/* did not contain a CSA */
819 	if (err)
820 		return false;
821 
822 	/* channel switch is not supported, disconnect */
823 	if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
824 		goto disconnect;
825 
826 	params.count = csa_ie.count;
827 	params.chandef = csa_ie.chandef;
828 
829 	switch (ifibss->chandef.width) {
830 	case NL80211_CHAN_WIDTH_20_NOHT:
831 	case NL80211_CHAN_WIDTH_20:
832 	case NL80211_CHAN_WIDTH_40:
833 		/* keep our current HT mode (HT20/HT40+/HT40-), even if
834 		 * another mode  has been announced. The mode is not adopted
835 		 * within the beacon while doing CSA and we should therefore
836 		 * keep the mode which we announce.
837 		 */
838 		ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
839 		cfg80211_chandef_create(&params.chandef, params.chandef.chan,
840 					ch_type);
841 		break;
842 	case NL80211_CHAN_WIDTH_5:
843 	case NL80211_CHAN_WIDTH_10:
844 		if (params.chandef.width != ifibss->chandef.width) {
845 			sdata_info(sdata,
846 				   "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
847 				   ifibss->bssid,
848 				   params.chandef.chan->center_freq,
849 				   params.chandef.width,
850 				   params.chandef.center_freq1,
851 				   params.chandef.center_freq2);
852 			goto disconnect;
853 		}
854 		break;
855 	default:
856 		/* should not happen, sta_flags should prevent VHT modes. */
857 		WARN_ON(1);
858 		goto disconnect;
859 	}
860 
861 	if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef,
862 				     NL80211_IFTYPE_ADHOC)) {
863 		sdata_info(sdata,
864 			   "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
865 			   ifibss->bssid,
866 			   params.chandef.chan->center_freq,
867 			   params.chandef.width,
868 			   params.chandef.center_freq1,
869 			   params.chandef.center_freq2);
870 		goto disconnect;
871 	}
872 
873 	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
874 					    &params.chandef,
875 					    NL80211_IFTYPE_ADHOC);
876 	if (err < 0)
877 		goto disconnect;
878 	if (err > 0 && !ifibss->userspace_handles_dfs) {
879 		/* IBSS-DFS only allowed with a control program */
880 		goto disconnect;
881 	}
882 
883 	params.radar_required = err;
884 
885 	if (cfg80211_chandef_identical(&params.chandef,
886 				       &sdata->vif.bss_conf.chandef)) {
887 		ibss_dbg(sdata,
888 			 "received csa with an identical chandef, ignoring\n");
889 		return true;
890 	}
891 
892 	/* all checks done, now perform the channel switch. */
893 	ibss_dbg(sdata,
894 		 "received channel switch announcement to go to channel %d MHz\n",
895 		 params.chandef.chan->center_freq);
896 
897 	params.block_tx = !!csa_ie.mode;
898 
899 	if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
900 				     &params))
901 		goto disconnect;
902 
903 	ieee80211_ibss_csa_mark_radar(sdata);
904 
905 	return true;
906 disconnect:
907 	ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
908 	ieee80211_queue_work(&sdata->local->hw,
909 			     &ifibss->csa_connection_drop_work);
910 
911 	ieee80211_ibss_csa_mark_radar(sdata);
912 
913 	return true;
914 }
915 
916 static void
917 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
918 				struct ieee80211_mgmt *mgmt, size_t len,
919 				struct ieee80211_rx_status *rx_status,
920 				struct ieee802_11_elems *elems)
921 {
922 	int required_len;
923 
924 	if (len < IEEE80211_MIN_ACTION_SIZE + 1)
925 		return;
926 
927 	/* CSA is the only action we handle for now */
928 	if (mgmt->u.action.u.measurement.action_code !=
929 	    WLAN_ACTION_SPCT_CHL_SWITCH)
930 		return;
931 
932 	required_len = IEEE80211_MIN_ACTION_SIZE +
933 		       sizeof(mgmt->u.action.u.chan_switch);
934 	if (len < required_len)
935 		return;
936 
937 	if (!sdata->vif.csa_active)
938 		ieee80211_ibss_process_chanswitch(sdata, elems, false);
939 }
940 
941 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
942 					  struct ieee80211_mgmt *mgmt,
943 					  size_t len)
944 {
945 	u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
946 
947 	if (len < IEEE80211_DEAUTH_FRAME_LEN)
948 		return;
949 
950 	ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
951 		 mgmt->sa, mgmt->da, mgmt->bssid, reason);
952 	sta_info_destroy_addr(sdata, mgmt->sa);
953 }
954 
955 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
956 					struct ieee80211_mgmt *mgmt,
957 					size_t len)
958 {
959 	u16 auth_alg, auth_transaction;
960 
961 	sdata_assert_lock(sdata);
962 
963 	if (len < 24 + 6)
964 		return;
965 
966 	auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
967 	auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
968 
969 	ibss_dbg(sdata,
970 		 "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
971 		 mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
972 
973 	if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
974 		return;
975 
976 	/*
977 	 * IEEE 802.11 standard does not require authentication in IBSS
978 	 * networks and most implementations do not seem to use it.
979 	 * However, try to reply to authentication attempts if someone
980 	 * has actually implemented this.
981 	 */
982 	ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
983 			    mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
984 }
985 
986 static void ieee80211_update_sta_info(struct ieee80211_sub_if_data *sdata,
987 				      struct ieee80211_mgmt *mgmt, size_t len,
988 				      struct ieee80211_rx_status *rx_status,
989 				      struct ieee802_11_elems *elems,
990 				      struct ieee80211_channel *channel)
991 {
992 	struct sta_info *sta;
993 	enum nl80211_band band = rx_status->band;
994 	enum nl80211_bss_scan_width scan_width;
995 	struct ieee80211_local *local = sdata->local;
996 	struct ieee80211_supported_band *sband;
997 	bool rates_updated = false;
998 	u32 supp_rates = 0;
999 
1000 	if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1001 		return;
1002 
1003 	if (!ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid))
1004 		return;
1005 
1006 	sband = local->hw.wiphy->bands[band];
1007 	if (WARN_ON(!sband))
1008 		return;
1009 
1010 	rcu_read_lock();
1011 	sta = sta_info_get(sdata, mgmt->sa);
1012 
1013 	if (elems->supp_rates) {
1014 		supp_rates = ieee80211_sta_get_rates(sdata, elems,
1015 						     band, NULL);
1016 		if (sta) {
1017 			u32 prev_rates;
1018 
1019 			prev_rates = sta->sta.supp_rates[band];
1020 			/* make sure mandatory rates are always added */
1021 			scan_width = NL80211_BSS_CHAN_WIDTH_20;
1022 			if (rx_status->bw == RATE_INFO_BW_5)
1023 				scan_width = NL80211_BSS_CHAN_WIDTH_5;
1024 			else if (rx_status->bw == RATE_INFO_BW_10)
1025 				scan_width = NL80211_BSS_CHAN_WIDTH_10;
1026 
1027 			sta->sta.supp_rates[band] = supp_rates |
1028 				ieee80211_mandatory_rates(sband, scan_width);
1029 			if (sta->sta.supp_rates[band] != prev_rates) {
1030 				ibss_dbg(sdata,
1031 					 "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1032 					 sta->sta.addr, prev_rates,
1033 					 sta->sta.supp_rates[band]);
1034 				rates_updated = true;
1035 			}
1036 		} else {
1037 			rcu_read_unlock();
1038 			sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1039 						     mgmt->sa, supp_rates);
1040 		}
1041 	}
1042 
1043 	if (sta && !sta->sta.wme &&
1044 	    elems->wmm_info && local->hw.queues >= IEEE80211_NUM_ACS) {
1045 		sta->sta.wme = true;
1046 		ieee80211_check_fast_xmit(sta);
1047 	}
1048 
1049 	if (sta && elems->ht_operation && elems->ht_cap_elem &&
1050 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1051 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1052 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1053 		/* we both use HT */
1054 		struct ieee80211_ht_cap htcap_ie;
1055 		struct cfg80211_chan_def chandef;
1056 		enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth;
1057 
1058 		cfg80211_chandef_create(&chandef, channel, NL80211_CHAN_NO_HT);
1059 		ieee80211_chandef_ht_oper(elems->ht_operation, &chandef);
1060 
1061 		memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1062 		rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
1063 								   &htcap_ie,
1064 								   sta);
1065 
1066 		if (elems->vht_operation && elems->vht_cap_elem &&
1067 		    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20 &&
1068 		    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_40) {
1069 			/* we both use VHT */
1070 			struct ieee80211_vht_cap cap_ie;
1071 			struct ieee80211_sta_vht_cap cap = sta->sta.vht_cap;
1072 
1073 			ieee80211_chandef_vht_oper(elems->vht_operation,
1074 						   &chandef);
1075 			memcpy(&cap_ie, elems->vht_cap_elem, sizeof(cap_ie));
1076 			ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
1077 							    &cap_ie, sta);
1078 			if (memcmp(&cap, &sta->sta.vht_cap, sizeof(cap)))
1079 				rates_updated |= true;
1080 		}
1081 
1082 		if (bw != sta->sta.bandwidth)
1083 			rates_updated |= true;
1084 
1085 		if (!cfg80211_chandef_compatible(&sdata->u.ibss.chandef,
1086 						 &chandef))
1087 			WARN_ON_ONCE(1);
1088 	}
1089 
1090 	if (sta && rates_updated) {
1091 		u32 changed = IEEE80211_RC_SUPP_RATES_CHANGED;
1092 		u8 rx_nss = sta->sta.rx_nss;
1093 
1094 		/* Force rx_nss recalculation */
1095 		sta->sta.rx_nss = 0;
1096 		rate_control_rate_init(sta);
1097 		if (sta->sta.rx_nss != rx_nss)
1098 			changed |= IEEE80211_RC_NSS_CHANGED;
1099 
1100 		drv_sta_rc_update(local, sdata, &sta->sta, changed);
1101 	}
1102 
1103 	rcu_read_unlock();
1104 }
1105 
1106 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
1107 				  struct ieee80211_mgmt *mgmt, size_t len,
1108 				  struct ieee80211_rx_status *rx_status,
1109 				  struct ieee802_11_elems *elems)
1110 {
1111 	struct ieee80211_local *local = sdata->local;
1112 	struct cfg80211_bss *cbss;
1113 	struct ieee80211_bss *bss;
1114 	struct ieee80211_channel *channel;
1115 	u64 beacon_timestamp, rx_timestamp;
1116 	u32 supp_rates = 0;
1117 	enum nl80211_band band = rx_status->band;
1118 
1119 	channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
1120 	if (!channel)
1121 		return;
1122 
1123 	ieee80211_update_sta_info(sdata, mgmt, len, rx_status, elems, channel);
1124 
1125 	bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
1126 					channel);
1127 	if (!bss)
1128 		return;
1129 
1130 	cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1131 
1132 	/* same for beacon and probe response */
1133 	beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1134 
1135 	/* check if we need to merge IBSS */
1136 
1137 	/* not an IBSS */
1138 	if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1139 		goto put_bss;
1140 
1141 	/* different channel */
1142 	if (sdata->u.ibss.fixed_channel &&
1143 	    sdata->u.ibss.chandef.chan != cbss->channel)
1144 		goto put_bss;
1145 
1146 	/* different SSID */
1147 	if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1148 	    memcmp(elems->ssid, sdata->u.ibss.ssid,
1149 				sdata->u.ibss.ssid_len))
1150 		goto put_bss;
1151 
1152 	/* process channel switch */
1153 	if (sdata->vif.csa_active ||
1154 	    ieee80211_ibss_process_chanswitch(sdata, elems, true))
1155 		goto put_bss;
1156 
1157 	/* same BSSID */
1158 	if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1159 		goto put_bss;
1160 
1161 	/* we use a fixed BSSID */
1162 	if (sdata->u.ibss.fixed_bssid)
1163 		goto put_bss;
1164 
1165 	if (ieee80211_have_rx_timestamp(rx_status)) {
1166 		/* time when timestamp field was received */
1167 		rx_timestamp =
1168 			ieee80211_calculate_rx_timestamp(local, rx_status,
1169 							 len + FCS_LEN, 24);
1170 	} else {
1171 		/*
1172 		 * second best option: get current TSF
1173 		 * (will return -1 if not supported)
1174 		 */
1175 		rx_timestamp = drv_get_tsf(local, sdata);
1176 	}
1177 
1178 	ibss_dbg(sdata,
1179 		 "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
1180 		 mgmt->sa, mgmt->bssid,
1181 		 (unsigned long long)rx_timestamp,
1182 		 (unsigned long long)beacon_timestamp,
1183 		 (unsigned long long)(rx_timestamp - beacon_timestamp),
1184 		 jiffies);
1185 
1186 	if (beacon_timestamp > rx_timestamp) {
1187 		ibss_dbg(sdata,
1188 			 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1189 			 mgmt->bssid);
1190 		ieee80211_sta_join_ibss(sdata, bss);
1191 		supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1192 		ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1193 				       supp_rates);
1194 		rcu_read_unlock();
1195 	}
1196 
1197  put_bss:
1198 	ieee80211_rx_bss_put(local, bss);
1199 }
1200 
1201 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1202 			      const u8 *bssid, const u8 *addr,
1203 			      u32 supp_rates)
1204 {
1205 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1206 	struct ieee80211_local *local = sdata->local;
1207 	struct sta_info *sta;
1208 	struct ieee80211_chanctx_conf *chanctx_conf;
1209 	struct ieee80211_supported_band *sband;
1210 	enum nl80211_bss_scan_width scan_width;
1211 	int band;
1212 
1213 	/*
1214 	 * XXX: Consider removing the least recently used entry and
1215 	 * 	allow new one to be added.
1216 	 */
1217 	if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1218 		net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1219 				    sdata->name, addr);
1220 		return;
1221 	}
1222 
1223 	if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1224 		return;
1225 
1226 	if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1227 		return;
1228 
1229 	rcu_read_lock();
1230 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1231 	if (WARN_ON_ONCE(!chanctx_conf)) {
1232 		rcu_read_unlock();
1233 		return;
1234 	}
1235 	band = chanctx_conf->def.chan->band;
1236 	scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1237 	rcu_read_unlock();
1238 
1239 	sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1240 	if (!sta)
1241 		return;
1242 
1243 	/* make sure mandatory rates are always added */
1244 	sband = local->hw.wiphy->bands[band];
1245 	sta->sta.supp_rates[band] = supp_rates |
1246 			ieee80211_mandatory_rates(sband, scan_width);
1247 
1248 	spin_lock(&ifibss->incomplete_lock);
1249 	list_add(&sta->list, &ifibss->incomplete_stations);
1250 	spin_unlock(&ifibss->incomplete_lock);
1251 	ieee80211_queue_work(&local->hw, &sdata->work);
1252 }
1253 
1254 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1255 {
1256 	struct ieee80211_local *local = sdata->local;
1257 	struct sta_info *sta, *tmp;
1258 	unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1259 	unsigned long exp_rsn = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1260 
1261 	mutex_lock(&local->sta_mtx);
1262 
1263 	list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1264 		unsigned long last_active = ieee80211_sta_last_active(sta);
1265 
1266 		if (sdata != sta->sdata)
1267 			continue;
1268 
1269 		if (time_is_before_jiffies(last_active + exp_time) ||
1270 		    (time_is_before_jiffies(last_active + exp_rsn) &&
1271 		     sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1272 			sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1273 				sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1274 				"not authorized " : "", sta->sta.addr);
1275 
1276 			WARN_ON(__sta_info_destroy(sta));
1277 		}
1278 	}
1279 
1280 	mutex_unlock(&local->sta_mtx);
1281 }
1282 
1283 /*
1284  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1285  */
1286 
1287 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1288 {
1289 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1290 	enum nl80211_bss_scan_width scan_width;
1291 
1292 	sdata_assert_lock(sdata);
1293 
1294 	mod_timer(&ifibss->timer,
1295 		  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1296 
1297 	ieee80211_ibss_sta_expire(sdata);
1298 
1299 	if (time_before(jiffies, ifibss->last_scan_completed +
1300 		       IEEE80211_IBSS_MERGE_INTERVAL))
1301 		return;
1302 
1303 	if (ieee80211_sta_active_ibss(sdata))
1304 		return;
1305 
1306 	if (ifibss->fixed_channel)
1307 		return;
1308 
1309 	sdata_info(sdata,
1310 		   "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1311 
1312 	scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1313 	ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1314 				    NULL, 0, scan_width);
1315 }
1316 
1317 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1318 {
1319 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1320 	u8 bssid[ETH_ALEN];
1321 	u16 capability;
1322 	int i;
1323 
1324 	sdata_assert_lock(sdata);
1325 
1326 	if (ifibss->fixed_bssid) {
1327 		memcpy(bssid, ifibss->bssid, ETH_ALEN);
1328 	} else {
1329 		/* Generate random, not broadcast, locally administered BSSID. Mix in
1330 		 * own MAC address to make sure that devices that do not have proper
1331 		 * random number generator get different BSSID. */
1332 		get_random_bytes(bssid, ETH_ALEN);
1333 		for (i = 0; i < ETH_ALEN; i++)
1334 			bssid[i] ^= sdata->vif.addr[i];
1335 		bssid[0] &= ~0x01;
1336 		bssid[0] |= 0x02;
1337 	}
1338 
1339 	sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1340 
1341 	capability = WLAN_CAPABILITY_IBSS;
1342 
1343 	if (ifibss->privacy)
1344 		capability |= WLAN_CAPABILITY_PRIVACY;
1345 
1346 	__ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1347 				  &ifibss->chandef, ifibss->basic_rates,
1348 				  capability, 0, true);
1349 }
1350 
1351 static unsigned ibss_setup_channels(struct wiphy *wiphy,
1352 				    struct ieee80211_channel **channels,
1353 				    unsigned int channels_max,
1354 				    u32 center_freq, u32 width)
1355 {
1356 	struct ieee80211_channel *chan = NULL;
1357 	unsigned int n_chan = 0;
1358 	u32 start_freq, end_freq, freq;
1359 
1360 	if (width <= 20) {
1361 		start_freq = center_freq;
1362 		end_freq = center_freq;
1363 	} else {
1364 		start_freq = center_freq - width / 2 + 10;
1365 		end_freq = center_freq + width / 2 - 10;
1366 	}
1367 
1368 	for (freq = start_freq; freq <= end_freq; freq += 20) {
1369 		chan = ieee80211_get_channel(wiphy, freq);
1370 		if (!chan)
1371 			continue;
1372 		if (n_chan >= channels_max)
1373 			return n_chan;
1374 
1375 		channels[n_chan] = chan;
1376 		n_chan++;
1377 	}
1378 
1379 	return n_chan;
1380 }
1381 
1382 static unsigned int
1383 ieee80211_ibss_setup_scan_channels(struct wiphy *wiphy,
1384 				   const struct cfg80211_chan_def *chandef,
1385 				   struct ieee80211_channel **channels,
1386 				   unsigned int channels_max)
1387 {
1388 	unsigned int n_chan = 0;
1389 	u32 width, cf1, cf2 = 0;
1390 
1391 	switch (chandef->width) {
1392 	case NL80211_CHAN_WIDTH_40:
1393 		width = 40;
1394 		break;
1395 	case NL80211_CHAN_WIDTH_80P80:
1396 		cf2 = chandef->center_freq2;
1397 		/* fall through */
1398 	case NL80211_CHAN_WIDTH_80:
1399 		width = 80;
1400 		break;
1401 	case NL80211_CHAN_WIDTH_160:
1402 		width = 160;
1403 		break;
1404 	default:
1405 		width = 20;
1406 		break;
1407 	}
1408 
1409 	cf1 = chandef->center_freq1;
1410 
1411 	n_chan = ibss_setup_channels(wiphy, channels, channels_max, cf1, width);
1412 
1413 	if (cf2)
1414 		n_chan += ibss_setup_channels(wiphy, &channels[n_chan],
1415 					      channels_max - n_chan, cf2,
1416 					      width);
1417 
1418 	return n_chan;
1419 }
1420 
1421 /*
1422  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1423  */
1424 
1425 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1426 {
1427 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1428 	struct ieee80211_local *local = sdata->local;
1429 	struct cfg80211_bss *cbss;
1430 	struct ieee80211_channel *chan = NULL;
1431 	const u8 *bssid = NULL;
1432 	enum nl80211_bss_scan_width scan_width;
1433 	int active_ibss;
1434 
1435 	sdata_assert_lock(sdata);
1436 
1437 	active_ibss = ieee80211_sta_active_ibss(sdata);
1438 	ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1439 
1440 	if (active_ibss)
1441 		return;
1442 
1443 	if (ifibss->fixed_bssid)
1444 		bssid = ifibss->bssid;
1445 	if (ifibss->fixed_channel)
1446 		chan = ifibss->chandef.chan;
1447 	if (!is_zero_ether_addr(ifibss->bssid))
1448 		bssid = ifibss->bssid;
1449 	cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1450 				ifibss->ssid, ifibss->ssid_len,
1451 				IEEE80211_BSS_TYPE_IBSS,
1452 				IEEE80211_PRIVACY(ifibss->privacy));
1453 
1454 	if (cbss) {
1455 		struct ieee80211_bss *bss;
1456 
1457 		bss = (void *)cbss->priv;
1458 		ibss_dbg(sdata,
1459 			 "sta_find_ibss: selected %pM current %pM\n",
1460 			 cbss->bssid, ifibss->bssid);
1461 		sdata_info(sdata,
1462 			   "Selected IBSS BSSID %pM based on configured SSID\n",
1463 			   cbss->bssid);
1464 
1465 		ieee80211_sta_join_ibss(sdata, bss);
1466 		ieee80211_rx_bss_put(local, bss);
1467 		return;
1468 	}
1469 
1470 	/* if a fixed bssid and a fixed freq have been provided create the IBSS
1471 	 * directly and do not waste time scanning
1472 	 */
1473 	if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1474 		sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1475 			   bssid);
1476 		ieee80211_sta_create_ibss(sdata);
1477 		return;
1478 	}
1479 
1480 
1481 	ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1482 
1483 	/* Selected IBSS not found in current scan results - try to scan */
1484 	if (time_after(jiffies, ifibss->last_scan_completed +
1485 					IEEE80211_SCAN_INTERVAL)) {
1486 		struct ieee80211_channel *channels[8];
1487 		unsigned int num;
1488 
1489 		sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1490 
1491 		scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1492 
1493 		if (ifibss->fixed_channel) {
1494 			num = ieee80211_ibss_setup_scan_channels(local->hw.wiphy,
1495 								 &ifibss->chandef,
1496 								 channels,
1497 								 ARRAY_SIZE(channels));
1498 			ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1499 						    ifibss->ssid_len, channels,
1500 						    num, scan_width);
1501 		} else {
1502 			ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1503 						    ifibss->ssid_len, NULL,
1504 						    0, scan_width);
1505 		}
1506 	} else {
1507 		int interval = IEEE80211_SCAN_INTERVAL;
1508 
1509 		if (time_after(jiffies, ifibss->ibss_join_req +
1510 			       IEEE80211_IBSS_JOIN_TIMEOUT))
1511 			ieee80211_sta_create_ibss(sdata);
1512 
1513 		mod_timer(&ifibss->timer,
1514 			  round_jiffies(jiffies + interval));
1515 	}
1516 }
1517 
1518 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1519 					struct sk_buff *req)
1520 {
1521 	struct ieee80211_mgmt *mgmt = (void *)req->data;
1522 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1523 	struct ieee80211_local *local = sdata->local;
1524 	int tx_last_beacon, len = req->len;
1525 	struct sk_buff *skb;
1526 	struct beacon_data *presp;
1527 	u8 *pos, *end;
1528 
1529 	sdata_assert_lock(sdata);
1530 
1531 	presp = rcu_dereference_protected(ifibss->presp,
1532 					  lockdep_is_held(&sdata->wdev.mtx));
1533 
1534 	if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1535 	    len < 24 + 2 || !presp)
1536 		return;
1537 
1538 	tx_last_beacon = drv_tx_last_beacon(local);
1539 
1540 	ibss_dbg(sdata,
1541 		 "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
1542 		 mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
1543 
1544 	if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1545 		return;
1546 
1547 	if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1548 	    !is_broadcast_ether_addr(mgmt->bssid))
1549 		return;
1550 
1551 	end = ((u8 *) mgmt) + len;
1552 	pos = mgmt->u.probe_req.variable;
1553 	if (pos[0] != WLAN_EID_SSID ||
1554 	    pos + 2 + pos[1] > end) {
1555 		ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1556 			 mgmt->sa);
1557 		return;
1558 	}
1559 	if (pos[1] != 0 &&
1560 	    (pos[1] != ifibss->ssid_len ||
1561 	     memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1562 		/* Ignore ProbeReq for foreign SSID */
1563 		return;
1564 	}
1565 
1566 	/* Reply with ProbeResp */
1567 	skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1568 	if (!skb)
1569 		return;
1570 
1571 	skb_reserve(skb, local->tx_headroom);
1572 	skb_put_data(skb, presp->head, presp->head_len);
1573 
1574 	memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1575 	ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1576 	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1577 
1578 	/* avoid excessive retries for probe request to wildcard SSIDs */
1579 	if (pos[1] == 0)
1580 		IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1581 
1582 	ieee80211_tx_skb(sdata, skb);
1583 }
1584 
1585 static
1586 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1587 				    struct ieee80211_mgmt *mgmt, size_t len,
1588 				    struct ieee80211_rx_status *rx_status)
1589 {
1590 	size_t baselen;
1591 	struct ieee802_11_elems elems;
1592 
1593 	BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1594 		     offsetof(typeof(mgmt->u.beacon), variable));
1595 
1596 	/*
1597 	 * either beacon or probe_resp but the variable field is at the
1598 	 * same offset
1599 	 */
1600 	baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1601 	if (baselen > len)
1602 		return;
1603 
1604 	ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1605 			       false, &elems);
1606 
1607 	ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1608 }
1609 
1610 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1611 				   struct sk_buff *skb)
1612 {
1613 	struct ieee80211_rx_status *rx_status;
1614 	struct ieee80211_mgmt *mgmt;
1615 	u16 fc;
1616 	struct ieee802_11_elems elems;
1617 	int ies_len;
1618 
1619 	rx_status = IEEE80211_SKB_RXCB(skb);
1620 	mgmt = (struct ieee80211_mgmt *) skb->data;
1621 	fc = le16_to_cpu(mgmt->frame_control);
1622 
1623 	sdata_lock(sdata);
1624 
1625 	if (!sdata->u.ibss.ssid_len)
1626 		goto mgmt_out; /* not ready to merge yet */
1627 
1628 	switch (fc & IEEE80211_FCTL_STYPE) {
1629 	case IEEE80211_STYPE_PROBE_REQ:
1630 		ieee80211_rx_mgmt_probe_req(sdata, skb);
1631 		break;
1632 	case IEEE80211_STYPE_PROBE_RESP:
1633 	case IEEE80211_STYPE_BEACON:
1634 		ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1635 					       rx_status);
1636 		break;
1637 	case IEEE80211_STYPE_AUTH:
1638 		ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1639 		break;
1640 	case IEEE80211_STYPE_DEAUTH:
1641 		ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1642 		break;
1643 	case IEEE80211_STYPE_ACTION:
1644 		switch (mgmt->u.action.category) {
1645 		case WLAN_CATEGORY_SPECTRUM_MGMT:
1646 			ies_len = skb->len -
1647 				  offsetof(struct ieee80211_mgmt,
1648 					   u.action.u.chan_switch.variable);
1649 
1650 			if (ies_len < 0)
1651 				break;
1652 
1653 			ieee802_11_parse_elems(
1654 				mgmt->u.action.u.chan_switch.variable,
1655 				ies_len, true, &elems);
1656 
1657 			if (elems.parse_error)
1658 				break;
1659 
1660 			ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1661 							rx_status, &elems);
1662 			break;
1663 		}
1664 	}
1665 
1666  mgmt_out:
1667 	sdata_unlock(sdata);
1668 }
1669 
1670 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1671 {
1672 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1673 	struct sta_info *sta;
1674 
1675 	sdata_lock(sdata);
1676 
1677 	/*
1678 	 * Work could be scheduled after scan or similar
1679 	 * when we aren't even joined (or trying) with a
1680 	 * network.
1681 	 */
1682 	if (!ifibss->ssid_len)
1683 		goto out;
1684 
1685 	spin_lock_bh(&ifibss->incomplete_lock);
1686 	while (!list_empty(&ifibss->incomplete_stations)) {
1687 		sta = list_first_entry(&ifibss->incomplete_stations,
1688 				       struct sta_info, list);
1689 		list_del(&sta->list);
1690 		spin_unlock_bh(&ifibss->incomplete_lock);
1691 
1692 		ieee80211_ibss_finish_sta(sta);
1693 		rcu_read_unlock();
1694 		spin_lock_bh(&ifibss->incomplete_lock);
1695 	}
1696 	spin_unlock_bh(&ifibss->incomplete_lock);
1697 
1698 	switch (ifibss->state) {
1699 	case IEEE80211_IBSS_MLME_SEARCH:
1700 		ieee80211_sta_find_ibss(sdata);
1701 		break;
1702 	case IEEE80211_IBSS_MLME_JOINED:
1703 		ieee80211_sta_merge_ibss(sdata);
1704 		break;
1705 	default:
1706 		WARN_ON(1);
1707 		break;
1708 	}
1709 
1710  out:
1711 	sdata_unlock(sdata);
1712 }
1713 
1714 static void ieee80211_ibss_timer(unsigned long data)
1715 {
1716 	struct ieee80211_sub_if_data *sdata =
1717 		(struct ieee80211_sub_if_data *) data;
1718 
1719 	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1720 }
1721 
1722 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1723 {
1724 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1725 
1726 	setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1727 		    (unsigned long) sdata);
1728 	INIT_LIST_HEAD(&ifibss->incomplete_stations);
1729 	spin_lock_init(&ifibss->incomplete_lock);
1730 	INIT_WORK(&ifibss->csa_connection_drop_work,
1731 		  ieee80211_csa_connection_drop_work);
1732 }
1733 
1734 /* scan finished notification */
1735 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1736 {
1737 	struct ieee80211_sub_if_data *sdata;
1738 
1739 	mutex_lock(&local->iflist_mtx);
1740 	list_for_each_entry(sdata, &local->interfaces, list) {
1741 		if (!ieee80211_sdata_running(sdata))
1742 			continue;
1743 		if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1744 			continue;
1745 		sdata->u.ibss.last_scan_completed = jiffies;
1746 	}
1747 	mutex_unlock(&local->iflist_mtx);
1748 }
1749 
1750 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1751 			struct cfg80211_ibss_params *params)
1752 {
1753 	u32 changed = 0;
1754 	u32 rate_flags;
1755 	struct ieee80211_supported_band *sband;
1756 	enum ieee80211_chanctx_mode chanmode;
1757 	struct ieee80211_local *local = sdata->local;
1758 	int radar_detect_width = 0;
1759 	int i;
1760 	int ret;
1761 
1762 	ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1763 					    &params->chandef,
1764 					    sdata->wdev.iftype);
1765 	if (ret < 0)
1766 		return ret;
1767 
1768 	if (ret > 0) {
1769 		if (!params->userspace_handles_dfs)
1770 			return -EINVAL;
1771 		radar_detect_width = BIT(params->chandef.width);
1772 	}
1773 
1774 	chanmode = (params->channel_fixed && !ret) ?
1775 		IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE;
1776 
1777 	mutex_lock(&local->chanctx_mtx);
1778 	ret = ieee80211_check_combinations(sdata, &params->chandef, chanmode,
1779 					   radar_detect_width);
1780 	mutex_unlock(&local->chanctx_mtx);
1781 	if (ret < 0)
1782 		return ret;
1783 
1784 	if (params->bssid) {
1785 		memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1786 		sdata->u.ibss.fixed_bssid = true;
1787 	} else
1788 		sdata->u.ibss.fixed_bssid = false;
1789 
1790 	sdata->u.ibss.privacy = params->privacy;
1791 	sdata->u.ibss.control_port = params->control_port;
1792 	sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1793 	sdata->u.ibss.basic_rates = params->basic_rates;
1794 	sdata->u.ibss.last_scan_completed = jiffies;
1795 
1796 	/* fix basic_rates if channel does not support these rates */
1797 	rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1798 	sband = local->hw.wiphy->bands[params->chandef.chan->band];
1799 	for (i = 0; i < sband->n_bitrates; i++) {
1800 		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1801 			sdata->u.ibss.basic_rates &= ~BIT(i);
1802 	}
1803 	memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1804 	       sizeof(params->mcast_rate));
1805 
1806 	sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1807 
1808 	sdata->u.ibss.chandef = params->chandef;
1809 	sdata->u.ibss.fixed_channel = params->channel_fixed;
1810 
1811 	if (params->ie) {
1812 		sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1813 					   GFP_KERNEL);
1814 		if (sdata->u.ibss.ie)
1815 			sdata->u.ibss.ie_len = params->ie_len;
1816 	}
1817 
1818 	sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1819 	sdata->u.ibss.ibss_join_req = jiffies;
1820 
1821 	memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1822 	sdata->u.ibss.ssid_len = params->ssid_len;
1823 
1824 	memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1825 	       sizeof(sdata->u.ibss.ht_capa));
1826 	memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1827 	       sizeof(sdata->u.ibss.ht_capa_mask));
1828 
1829 	/*
1830 	 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1831 	 * reserved, but an HT STA shall protect HT transmissions as though
1832 	 * the HT Protection field were set to non-HT mixed mode.
1833 	 *
1834 	 * In an IBSS, the RIFS Mode field of the HT Operation element is
1835 	 * also reserved, but an HT STA shall operate as though this field
1836 	 * were set to 1.
1837 	 */
1838 
1839 	sdata->vif.bss_conf.ht_operation_mode |=
1840 		  IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1841 		| IEEE80211_HT_PARAM_RIFS_MODE;
1842 
1843 	changed |= BSS_CHANGED_HT;
1844 	ieee80211_bss_info_change_notify(sdata, changed);
1845 
1846 	sdata->smps_mode = IEEE80211_SMPS_OFF;
1847 	sdata->needed_rx_chains = local->rx_chains;
1848 
1849 	ieee80211_queue_work(&local->hw, &sdata->work);
1850 
1851 	return 0;
1852 }
1853 
1854 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1855 {
1856 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1857 
1858 	ieee80211_ibss_disconnect(sdata);
1859 	ifibss->ssid_len = 0;
1860 	eth_zero_addr(ifibss->bssid);
1861 
1862 	/* remove beacon */
1863 	kfree(sdata->u.ibss.ie);
1864 
1865 	/* on the next join, re-program HT parameters */
1866 	memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1867 	memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1868 
1869 	synchronize_rcu();
1870 
1871 	skb_queue_purge(&sdata->skb_queue);
1872 
1873 	del_timer_sync(&sdata->u.ibss.timer);
1874 
1875 	return 0;
1876 }
1877