xref: /openbmc/linux/net/mac80211/ibss.c (revision 110e6f26)
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 		    ifibss->ie_len;
70 	presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
71 	if (!presp)
72 		return NULL;
73 
74 	presp->head = (void *)(presp + 1);
75 
76 	mgmt = (void *) presp->head;
77 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
78 					  IEEE80211_STYPE_PROBE_RESP);
79 	eth_broadcast_addr(mgmt->da);
80 	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
81 	memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
82 	mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
83 	mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
84 	mgmt->u.beacon.capab_info = cpu_to_le16(capability);
85 
86 	pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
87 
88 	*pos++ = WLAN_EID_SSID;
89 	*pos++ = ifibss->ssid_len;
90 	memcpy(pos, ifibss->ssid, ifibss->ssid_len);
91 	pos += ifibss->ssid_len;
92 
93 	sband = local->hw.wiphy->bands[chandef->chan->band];
94 	rate_flags = ieee80211_chandef_rate_flags(chandef);
95 	shift = ieee80211_chandef_get_shift(chandef);
96 	rates_n = 0;
97 	if (have_higher_than_11mbit)
98 		*have_higher_than_11mbit = false;
99 
100 	for (i = 0; i < sband->n_bitrates; i++) {
101 		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
102 			continue;
103 		if (sband->bitrates[i].bitrate > 110 &&
104 		    have_higher_than_11mbit)
105 			*have_higher_than_11mbit = true;
106 
107 		rates |= BIT(i);
108 		rates_n++;
109 	}
110 
111 	*pos++ = WLAN_EID_SUPP_RATES;
112 	*pos++ = min_t(int, 8, rates_n);
113 	for (ri = 0; ri < sband->n_bitrates; ri++) {
114 		int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
115 					5 * (1 << shift));
116 		u8 basic = 0;
117 		if (!(rates & BIT(ri)))
118 			continue;
119 
120 		if (basic_rates & BIT(ri))
121 			basic = 0x80;
122 		*pos++ = basic | (u8) rate;
123 		if (++rates_added == 8) {
124 			ri++; /* continue at next rate for EXT_SUPP_RATES */
125 			break;
126 		}
127 	}
128 
129 	if (sband->band == IEEE80211_BAND_2GHZ) {
130 		*pos++ = WLAN_EID_DS_PARAMS;
131 		*pos++ = 1;
132 		*pos++ = ieee80211_frequency_to_channel(
133 				chandef->chan->center_freq);
134 	}
135 
136 	*pos++ = WLAN_EID_IBSS_PARAMS;
137 	*pos++ = 2;
138 	/* FIX: set ATIM window based on scan results */
139 	*pos++ = 0;
140 	*pos++ = 0;
141 
142 	if (csa_settings) {
143 		*pos++ = WLAN_EID_CHANNEL_SWITCH;
144 		*pos++ = 3;
145 		*pos++ = csa_settings->block_tx ? 1 : 0;
146 		*pos++ = ieee80211_frequency_to_channel(
147 				csa_settings->chandef.chan->center_freq);
148 		presp->csa_counter_offsets[0] = (pos - presp->head);
149 		*pos++ = csa_settings->count;
150 		presp->csa_current_counter = csa_settings->count;
151 	}
152 
153 	/* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
154 	if (rates_n > 8) {
155 		*pos++ = WLAN_EID_EXT_SUPP_RATES;
156 		*pos++ = rates_n - 8;
157 		for (; ri < sband->n_bitrates; ri++) {
158 			int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
159 						5 * (1 << shift));
160 			u8 basic = 0;
161 			if (!(rates & BIT(ri)))
162 				continue;
163 
164 			if (basic_rates & BIT(ri))
165 				basic = 0x80;
166 			*pos++ = basic | (u8) rate;
167 		}
168 	}
169 
170 	if (ifibss->ie_len) {
171 		memcpy(pos, ifibss->ie, ifibss->ie_len);
172 		pos += ifibss->ie_len;
173 	}
174 
175 	/* add HT capability and information IEs */
176 	if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT &&
177 	    chandef->width != NL80211_CHAN_WIDTH_5 &&
178 	    chandef->width != NL80211_CHAN_WIDTH_10 &&
179 	    sband->ht_cap.ht_supported) {
180 		struct ieee80211_sta_ht_cap ht_cap;
181 
182 		memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
183 		ieee80211_apply_htcap_overrides(sdata, &ht_cap);
184 
185 		pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
186 		/*
187 		 * Note: According to 802.11n-2009 9.13.3.1, HT Protection
188 		 * field and RIFS Mode are reserved in IBSS mode, therefore
189 		 * keep them at 0
190 		 */
191 		pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
192 						 chandef, 0, false);
193 
194 		/* add VHT capability and information IEs */
195 		if (chandef->width != NL80211_CHAN_WIDTH_20 &&
196 		    chandef->width != NL80211_CHAN_WIDTH_40 &&
197 		    sband->vht_cap.vht_supported) {
198 			pos = ieee80211_ie_build_vht_cap(pos, &sband->vht_cap,
199 							 sband->vht_cap.cap);
200 			pos = ieee80211_ie_build_vht_oper(pos, &sband->vht_cap,
201 							  chandef);
202 		}
203 	}
204 
205 	if (local->hw.queues >= IEEE80211_NUM_ACS)
206 		pos = ieee80211_add_wmm_info_ie(pos, 0); /* U-APSD not in use */
207 
208 	presp->head_len = pos - presp->head;
209 	if (WARN_ON(presp->head_len > frame_len))
210 		goto error;
211 
212 	return presp;
213 error:
214 	kfree(presp);
215 	return NULL;
216 }
217 
218 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
219 				      const u8 *bssid, const int beacon_int,
220 				      struct cfg80211_chan_def *req_chandef,
221 				      const u32 basic_rates,
222 				      const u16 capability, u64 tsf,
223 				      bool creator)
224 {
225 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
226 	struct ieee80211_local *local = sdata->local;
227 	struct ieee80211_mgmt *mgmt;
228 	struct cfg80211_bss *bss;
229 	u32 bss_change;
230 	struct cfg80211_chan_def chandef;
231 	struct ieee80211_channel *chan;
232 	struct beacon_data *presp;
233 	struct cfg80211_inform_bss bss_meta = {};
234 	bool have_higher_than_11mbit;
235 	bool radar_required;
236 	int err;
237 
238 	sdata_assert_lock(sdata);
239 
240 	/* Reset own TSF to allow time synchronization work. */
241 	drv_reset_tsf(local, sdata);
242 
243 	if (!ether_addr_equal(ifibss->bssid, bssid))
244 		sta_info_flush(sdata);
245 
246 	/* if merging, indicate to driver that we leave the old IBSS */
247 	if (sdata->vif.bss_conf.ibss_joined) {
248 		sdata->vif.bss_conf.ibss_joined = false;
249 		sdata->vif.bss_conf.ibss_creator = false;
250 		sdata->vif.bss_conf.enable_beacon = false;
251 		netif_carrier_off(sdata->dev);
252 		ieee80211_bss_info_change_notify(sdata,
253 						 BSS_CHANGED_IBSS |
254 						 BSS_CHANGED_BEACON_ENABLED);
255 		drv_leave_ibss(local, sdata);
256 	}
257 
258 	presp = rcu_dereference_protected(ifibss->presp,
259 					  lockdep_is_held(&sdata->wdev.mtx));
260 	RCU_INIT_POINTER(ifibss->presp, NULL);
261 	if (presp)
262 		kfree_rcu(presp, rcu_head);
263 
264 	/* make a copy of the chandef, it could be modified below. */
265 	chandef = *req_chandef;
266 	chan = chandef.chan;
267 	if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
268 				     NL80211_IFTYPE_ADHOC)) {
269 		if (chandef.width == NL80211_CHAN_WIDTH_5 ||
270 		    chandef.width == NL80211_CHAN_WIDTH_10 ||
271 		    chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
272 		    chandef.width == NL80211_CHAN_WIDTH_20) {
273 			sdata_info(sdata,
274 				   "Failed to join IBSS, beacons forbidden\n");
275 			return;
276 		}
277 		chandef.width = NL80211_CHAN_WIDTH_20;
278 		chandef.center_freq1 = chan->center_freq;
279 		/* check again for downgraded chandef */
280 		if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
281 					     NL80211_IFTYPE_ADHOC)) {
282 			sdata_info(sdata,
283 				   "Failed to join IBSS, beacons forbidden\n");
284 			return;
285 		}
286 	}
287 
288 	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
289 					    &chandef, NL80211_IFTYPE_ADHOC);
290 	if (err < 0) {
291 		sdata_info(sdata,
292 			   "Failed to join IBSS, invalid chandef\n");
293 		return;
294 	}
295 	if (err > 0 && !ifibss->userspace_handles_dfs) {
296 		sdata_info(sdata,
297 			   "Failed to join IBSS, DFS channel without control program\n");
298 		return;
299 	}
300 
301 	radar_required = err;
302 
303 	mutex_lock(&local->mtx);
304 	if (ieee80211_vif_use_channel(sdata, &chandef,
305 				      ifibss->fixed_channel ?
306 					IEEE80211_CHANCTX_SHARED :
307 					IEEE80211_CHANCTX_EXCLUSIVE)) {
308 		sdata_info(sdata, "Failed to join IBSS, no channel context\n");
309 		mutex_unlock(&local->mtx);
310 		return;
311 	}
312 	sdata->radar_required = radar_required;
313 	mutex_unlock(&local->mtx);
314 
315 	memcpy(ifibss->bssid, bssid, ETH_ALEN);
316 
317 	presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
318 					   capability, tsf, &chandef,
319 					   &have_higher_than_11mbit, NULL);
320 	if (!presp)
321 		return;
322 
323 	rcu_assign_pointer(ifibss->presp, presp);
324 	mgmt = (void *)presp->head;
325 
326 	sdata->vif.bss_conf.enable_beacon = true;
327 	sdata->vif.bss_conf.beacon_int = beacon_int;
328 	sdata->vif.bss_conf.basic_rates = basic_rates;
329 	sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
330 	memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
331 	bss_change = BSS_CHANGED_BEACON_INT;
332 	bss_change |= ieee80211_reset_erp_info(sdata);
333 	bss_change |= BSS_CHANGED_BSSID;
334 	bss_change |= BSS_CHANGED_BEACON;
335 	bss_change |= BSS_CHANGED_BEACON_ENABLED;
336 	bss_change |= BSS_CHANGED_BASIC_RATES;
337 	bss_change |= BSS_CHANGED_HT;
338 	bss_change |= BSS_CHANGED_IBSS;
339 	bss_change |= BSS_CHANGED_SSID;
340 
341 	/*
342 	 * In 5 GHz/802.11a, we can always use short slot time.
343 	 * (IEEE 802.11-2012 18.3.8.7)
344 	 *
345 	 * In 2.4GHz, we must always use long slots in IBSS for compatibility
346 	 * reasons.
347 	 * (IEEE 802.11-2012 19.4.5)
348 	 *
349 	 * HT follows these specifications (IEEE 802.11-2012 20.3.18)
350 	 */
351 	sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
352 	bss_change |= BSS_CHANGED_ERP_SLOT;
353 
354 	/* cf. IEEE 802.11 9.2.12 */
355 	if (chan->band == IEEE80211_BAND_2GHZ && have_higher_than_11mbit)
356 		sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
357 	else
358 		sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
359 
360 	ieee80211_set_wmm_default(sdata, true, false);
361 
362 	sdata->vif.bss_conf.ibss_joined = true;
363 	sdata->vif.bss_conf.ibss_creator = creator;
364 
365 	err = drv_join_ibss(local, sdata);
366 	if (err) {
367 		sdata->vif.bss_conf.ibss_joined = false;
368 		sdata->vif.bss_conf.ibss_creator = false;
369 		sdata->vif.bss_conf.enable_beacon = false;
370 		sdata->vif.bss_conf.ssid_len = 0;
371 		RCU_INIT_POINTER(ifibss->presp, NULL);
372 		kfree_rcu(presp, rcu_head);
373 		mutex_lock(&local->mtx);
374 		ieee80211_vif_release_channel(sdata);
375 		mutex_unlock(&local->mtx);
376 		sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
377 			   err);
378 		return;
379 	}
380 
381 	ieee80211_bss_info_change_notify(sdata, bss_change);
382 
383 	ifibss->state = IEEE80211_IBSS_MLME_JOINED;
384 	mod_timer(&ifibss->timer,
385 		  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
386 
387 	bss_meta.chan = chan;
388 	bss_meta.scan_width = cfg80211_chandef_to_scan_width(&chandef);
389 	bss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta, mgmt,
390 					     presp->head_len, GFP_KERNEL);
391 
392 	cfg80211_put_bss(local->hw.wiphy, bss);
393 	netif_carrier_on(sdata->dev);
394 	cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
395 }
396 
397 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
398 				    struct ieee80211_bss *bss)
399 {
400 	struct cfg80211_bss *cbss =
401 		container_of((void *)bss, struct cfg80211_bss, priv);
402 	struct ieee80211_supported_band *sband;
403 	struct cfg80211_chan_def chandef;
404 	u32 basic_rates;
405 	int i, j;
406 	u16 beacon_int = cbss->beacon_interval;
407 	const struct cfg80211_bss_ies *ies;
408 	enum nl80211_channel_type chan_type;
409 	u64 tsf;
410 	u32 rate_flags;
411 	int shift;
412 
413 	sdata_assert_lock(sdata);
414 
415 	if (beacon_int < 10)
416 		beacon_int = 10;
417 
418 	switch (sdata->u.ibss.chandef.width) {
419 	case NL80211_CHAN_WIDTH_20_NOHT:
420 	case NL80211_CHAN_WIDTH_20:
421 	case NL80211_CHAN_WIDTH_40:
422 		chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
423 		cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
424 		break;
425 	case NL80211_CHAN_WIDTH_5:
426 	case NL80211_CHAN_WIDTH_10:
427 		cfg80211_chandef_create(&chandef, cbss->channel,
428 					NL80211_CHAN_WIDTH_20_NOHT);
429 		chandef.width = sdata->u.ibss.chandef.width;
430 		break;
431 	case NL80211_CHAN_WIDTH_80:
432 	case NL80211_CHAN_WIDTH_80P80:
433 	case NL80211_CHAN_WIDTH_160:
434 		chandef = sdata->u.ibss.chandef;
435 		chandef.chan = cbss->channel;
436 		break;
437 	default:
438 		/* fall back to 20 MHz for unsupported modes */
439 		cfg80211_chandef_create(&chandef, cbss->channel,
440 					NL80211_CHAN_WIDTH_20_NOHT);
441 		break;
442 	}
443 
444 	sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
445 	rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
446 	shift = ieee80211_vif_get_shift(&sdata->vif);
447 
448 	basic_rates = 0;
449 
450 	for (i = 0; i < bss->supp_rates_len; i++) {
451 		int rate = bss->supp_rates[i] & 0x7f;
452 		bool is_basic = !!(bss->supp_rates[i] & 0x80);
453 
454 		for (j = 0; j < sband->n_bitrates; j++) {
455 			int brate;
456 			if ((rate_flags & sband->bitrates[j].flags)
457 			    != rate_flags)
458 				continue;
459 
460 			brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
461 					     5 * (1 << shift));
462 			if (brate == rate) {
463 				if (is_basic)
464 					basic_rates |= BIT(j);
465 				break;
466 			}
467 		}
468 	}
469 
470 	rcu_read_lock();
471 	ies = rcu_dereference(cbss->ies);
472 	tsf = ies->tsf;
473 	rcu_read_unlock();
474 
475 	__ieee80211_sta_join_ibss(sdata, cbss->bssid,
476 				  beacon_int,
477 				  &chandef,
478 				  basic_rates,
479 				  cbss->capability,
480 				  tsf, false);
481 }
482 
483 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
484 			      struct cfg80211_csa_settings *csa_settings)
485 {
486 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
487 	struct beacon_data *presp, *old_presp;
488 	struct cfg80211_bss *cbss;
489 	const struct cfg80211_bss_ies *ies;
490 	u16 capability = 0;
491 	u64 tsf;
492 	int ret = 0;
493 
494 	sdata_assert_lock(sdata);
495 
496 	if (ifibss->privacy)
497 		capability = WLAN_CAPABILITY_PRIVACY;
498 
499 	cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
500 				ifibss->bssid, ifibss->ssid,
501 				ifibss->ssid_len, IEEE80211_BSS_TYPE_IBSS,
502 				IEEE80211_PRIVACY(ifibss->privacy));
503 
504 	if (WARN_ON(!cbss)) {
505 		ret = -EINVAL;
506 		goto out;
507 	}
508 
509 	rcu_read_lock();
510 	ies = rcu_dereference(cbss->ies);
511 	tsf = ies->tsf;
512 	rcu_read_unlock();
513 	cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
514 
515 	old_presp = rcu_dereference_protected(ifibss->presp,
516 					  lockdep_is_held(&sdata->wdev.mtx));
517 
518 	presp = ieee80211_ibss_build_presp(sdata,
519 					   sdata->vif.bss_conf.beacon_int,
520 					   sdata->vif.bss_conf.basic_rates,
521 					   capability, tsf, &ifibss->chandef,
522 					   NULL, csa_settings);
523 	if (!presp) {
524 		ret = -ENOMEM;
525 		goto out;
526 	}
527 
528 	rcu_assign_pointer(ifibss->presp, presp);
529 	if (old_presp)
530 		kfree_rcu(old_presp, rcu_head);
531 
532 	return BSS_CHANGED_BEACON;
533  out:
534 	return ret;
535 }
536 
537 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
538 {
539 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
540 	struct cfg80211_bss *cbss;
541 	int err, changed = 0;
542 
543 	sdata_assert_lock(sdata);
544 
545 	/* update cfg80211 bss information with the new channel */
546 	if (!is_zero_ether_addr(ifibss->bssid)) {
547 		cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
548 					ifibss->chandef.chan,
549 					ifibss->bssid, ifibss->ssid,
550 					ifibss->ssid_len,
551 					IEEE80211_BSS_TYPE_IBSS,
552 					IEEE80211_PRIVACY(ifibss->privacy));
553 		/* XXX: should not really modify cfg80211 data */
554 		if (cbss) {
555 			cbss->channel = sdata->csa_chandef.chan;
556 			cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
557 		}
558 	}
559 
560 	ifibss->chandef = sdata->csa_chandef;
561 
562 	/* generate the beacon */
563 	err = ieee80211_ibss_csa_beacon(sdata, NULL);
564 	if (err < 0)
565 		return err;
566 
567 	changed |= err;
568 
569 	return changed;
570 }
571 
572 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
573 {
574 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
575 
576 	cancel_work_sync(&ifibss->csa_connection_drop_work);
577 }
578 
579 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
580 	__acquires(RCU)
581 {
582 	struct ieee80211_sub_if_data *sdata = sta->sdata;
583 	u8 addr[ETH_ALEN];
584 
585 	memcpy(addr, sta->sta.addr, ETH_ALEN);
586 
587 	ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
588 
589 	sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
590 	sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
591 	/* authorize the station only if the network is not RSN protected. If
592 	 * not wait for the userspace to authorize it */
593 	if (!sta->sdata->u.ibss.control_port)
594 		sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
595 
596 	rate_control_rate_init(sta);
597 
598 	/* If it fails, maybe we raced another insertion? */
599 	if (sta_info_insert_rcu(sta))
600 		return sta_info_get(sdata, addr);
601 	return sta;
602 }
603 
604 static struct sta_info *
605 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
606 		       const u8 *addr, u32 supp_rates)
607 	__acquires(RCU)
608 {
609 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
610 	struct ieee80211_local *local = sdata->local;
611 	struct sta_info *sta;
612 	struct ieee80211_chanctx_conf *chanctx_conf;
613 	struct ieee80211_supported_band *sband;
614 	enum nl80211_bss_scan_width scan_width;
615 	int band;
616 
617 	/*
618 	 * XXX: Consider removing the least recently used entry and
619 	 * 	allow new one to be added.
620 	 */
621 	if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
622 		net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
623 				    sdata->name, addr);
624 		rcu_read_lock();
625 		return NULL;
626 	}
627 
628 	if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
629 		rcu_read_lock();
630 		return NULL;
631 	}
632 
633 	if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
634 		rcu_read_lock();
635 		return NULL;
636 	}
637 
638 	rcu_read_lock();
639 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
640 	if (WARN_ON_ONCE(!chanctx_conf))
641 		return NULL;
642 	band = chanctx_conf->def.chan->band;
643 	scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
644 	rcu_read_unlock();
645 
646 	sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
647 	if (!sta) {
648 		rcu_read_lock();
649 		return NULL;
650 	}
651 
652 	sta->rx_stats.last_rx = jiffies;
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 		if (sta->sdata == sdata &&
674 		    time_after(sta->rx_stats.last_rx +
675 			       IEEE80211_IBSS_MERGE_INTERVAL,
676 			       jiffies)) {
677 			active++;
678 			break;
679 		}
680 	}
681 
682 	rcu_read_unlock();
683 
684 	return active;
685 }
686 
687 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
688 {
689 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
690 	struct ieee80211_local *local = sdata->local;
691 	struct cfg80211_bss *cbss;
692 	struct beacon_data *presp;
693 	struct sta_info *sta;
694 
695 	if (!is_zero_ether_addr(ifibss->bssid)) {
696 		cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
697 					ifibss->bssid, ifibss->ssid,
698 					ifibss->ssid_len,
699 					IEEE80211_BSS_TYPE_IBSS,
700 					IEEE80211_PRIVACY(ifibss->privacy));
701 
702 		if (cbss) {
703 			cfg80211_unlink_bss(local->hw.wiphy, cbss);
704 			cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
705 		}
706 	}
707 
708 	ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
709 
710 	sta_info_flush(sdata);
711 
712 	spin_lock_bh(&ifibss->incomplete_lock);
713 	while (!list_empty(&ifibss->incomplete_stations)) {
714 		sta = list_first_entry(&ifibss->incomplete_stations,
715 				       struct sta_info, list);
716 		list_del(&sta->list);
717 		spin_unlock_bh(&ifibss->incomplete_lock);
718 
719 		sta_info_free(local, sta);
720 		spin_lock_bh(&ifibss->incomplete_lock);
721 	}
722 	spin_unlock_bh(&ifibss->incomplete_lock);
723 
724 	netif_carrier_off(sdata->dev);
725 
726 	sdata->vif.bss_conf.ibss_joined = false;
727 	sdata->vif.bss_conf.ibss_creator = false;
728 	sdata->vif.bss_conf.enable_beacon = false;
729 	sdata->vif.bss_conf.ssid_len = 0;
730 
731 	/* remove beacon */
732 	presp = rcu_dereference_protected(ifibss->presp,
733 					  lockdep_is_held(&sdata->wdev.mtx));
734 	RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
735 	if (presp)
736 		kfree_rcu(presp, rcu_head);
737 
738 	clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
739 	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
740 						BSS_CHANGED_IBSS);
741 	drv_leave_ibss(local, sdata);
742 	mutex_lock(&local->mtx);
743 	ieee80211_vif_release_channel(sdata);
744 	mutex_unlock(&local->mtx);
745 }
746 
747 static void ieee80211_csa_connection_drop_work(struct work_struct *work)
748 {
749 	struct ieee80211_sub_if_data *sdata =
750 		container_of(work, struct ieee80211_sub_if_data,
751 			     u.ibss.csa_connection_drop_work);
752 
753 	sdata_lock(sdata);
754 
755 	ieee80211_ibss_disconnect(sdata);
756 	synchronize_rcu();
757 	skb_queue_purge(&sdata->skb_queue);
758 
759 	/* trigger a scan to find another IBSS network to join */
760 	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
761 
762 	sdata_unlock(sdata);
763 }
764 
765 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
766 {
767 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
768 	int err;
769 
770 	/* if the current channel is a DFS channel, mark the channel as
771 	 * unavailable.
772 	 */
773 	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
774 					    &ifibss->chandef,
775 					    NL80211_IFTYPE_ADHOC);
776 	if (err > 0)
777 		cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
778 				     GFP_ATOMIC);
779 }
780 
781 static bool
782 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
783 				  struct ieee802_11_elems *elems,
784 				  bool beacon)
785 {
786 	struct cfg80211_csa_settings params;
787 	struct ieee80211_csa_ie csa_ie;
788 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
789 	enum nl80211_channel_type ch_type;
790 	int err;
791 	u32 sta_flags;
792 
793 	sdata_assert_lock(sdata);
794 
795 	sta_flags = IEEE80211_STA_DISABLE_VHT;
796 	switch (ifibss->chandef.width) {
797 	case NL80211_CHAN_WIDTH_5:
798 	case NL80211_CHAN_WIDTH_10:
799 	case NL80211_CHAN_WIDTH_20_NOHT:
800 		sta_flags |= IEEE80211_STA_DISABLE_HT;
801 		/* fall through */
802 	case NL80211_CHAN_WIDTH_20:
803 		sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
804 		break;
805 	default:
806 		break;
807 	}
808 
809 	memset(&params, 0, sizeof(params));
810 	memset(&csa_ie, 0, sizeof(csa_ie));
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 ieee80211_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 = local->hw.wiphy->bands[band];
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 	rcu_read_lock();
1007 	sta = sta_info_get(sdata, mgmt->sa);
1008 
1009 	if (elems->supp_rates) {
1010 		supp_rates = ieee80211_sta_get_rates(sdata, elems,
1011 						     band, NULL);
1012 		if (sta) {
1013 			u32 prev_rates;
1014 
1015 			prev_rates = sta->sta.supp_rates[band];
1016 			/* make sure mandatory rates are always added */
1017 			scan_width = NL80211_BSS_CHAN_WIDTH_20;
1018 			if (rx_status->flag & RX_FLAG_5MHZ)
1019 				scan_width = NL80211_BSS_CHAN_WIDTH_5;
1020 			if (rx_status->flag & RX_FLAG_10MHZ)
1021 				scan_width = NL80211_BSS_CHAN_WIDTH_10;
1022 
1023 			sta->sta.supp_rates[band] = supp_rates |
1024 				ieee80211_mandatory_rates(sband, scan_width);
1025 			if (sta->sta.supp_rates[band] != prev_rates) {
1026 				ibss_dbg(sdata,
1027 					 "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1028 					 sta->sta.addr, prev_rates,
1029 					 sta->sta.supp_rates[band]);
1030 				rates_updated = true;
1031 			}
1032 		} else {
1033 			rcu_read_unlock();
1034 			sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1035 						     mgmt->sa, supp_rates);
1036 		}
1037 	}
1038 
1039 	if (sta && !sta->sta.wme &&
1040 	    elems->wmm_info && local->hw.queues >= IEEE80211_NUM_ACS) {
1041 		sta->sta.wme = true;
1042 		ieee80211_check_fast_xmit(sta);
1043 	}
1044 
1045 	if (sta && elems->ht_operation && elems->ht_cap_elem &&
1046 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1047 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1048 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1049 		/* we both use HT */
1050 		struct ieee80211_ht_cap htcap_ie;
1051 		struct cfg80211_chan_def chandef;
1052 		enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth;
1053 
1054 		cfg80211_chandef_create(&chandef, channel, NL80211_CHAN_NO_HT);
1055 		ieee80211_chandef_ht_oper(elems->ht_operation, &chandef);
1056 
1057 		memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1058 		rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
1059 								   &htcap_ie,
1060 								   sta);
1061 
1062 		if (elems->vht_operation && elems->vht_cap_elem &&
1063 		    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20 &&
1064 		    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_40) {
1065 			/* we both use VHT */
1066 			struct ieee80211_vht_cap cap_ie;
1067 			struct ieee80211_sta_vht_cap cap = sta->sta.vht_cap;
1068 
1069 			ieee80211_chandef_vht_oper(elems->vht_operation,
1070 						   &chandef);
1071 			memcpy(&cap_ie, elems->vht_cap_elem, sizeof(cap_ie));
1072 			ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
1073 							    &cap_ie, sta);
1074 			if (memcmp(&cap, &sta->sta.vht_cap, sizeof(cap)))
1075 				rates_updated |= true;
1076 		}
1077 
1078 		if (bw != sta->sta.bandwidth)
1079 			rates_updated |= true;
1080 
1081 		if (!cfg80211_chandef_compatible(&sdata->u.ibss.chandef,
1082 						 &chandef))
1083 			WARN_ON_ONCE(1);
1084 	}
1085 
1086 	if (sta && rates_updated) {
1087 		u32 changed = IEEE80211_RC_SUPP_RATES_CHANGED;
1088 		u8 rx_nss = sta->sta.rx_nss;
1089 
1090 		/* Force rx_nss recalculation */
1091 		sta->sta.rx_nss = 0;
1092 		rate_control_rate_init(sta);
1093 		if (sta->sta.rx_nss != rx_nss)
1094 			changed |= IEEE80211_RC_NSS_CHANGED;
1095 
1096 		drv_sta_rc_update(local, sdata, &sta->sta, changed);
1097 	}
1098 
1099 	rcu_read_unlock();
1100 }
1101 
1102 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
1103 				  struct ieee80211_mgmt *mgmt, size_t len,
1104 				  struct ieee80211_rx_status *rx_status,
1105 				  struct ieee802_11_elems *elems)
1106 {
1107 	struct ieee80211_local *local = sdata->local;
1108 	struct cfg80211_bss *cbss;
1109 	struct ieee80211_bss *bss;
1110 	struct ieee80211_channel *channel;
1111 	u64 beacon_timestamp, rx_timestamp;
1112 	u32 supp_rates = 0;
1113 	enum ieee80211_band band = rx_status->band;
1114 
1115 	channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
1116 	if (!channel)
1117 		return;
1118 
1119 	ieee80211_update_sta_info(sdata, mgmt, len, rx_status, elems, channel);
1120 
1121 	bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
1122 					channel);
1123 	if (!bss)
1124 		return;
1125 
1126 	cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1127 
1128 	/* same for beacon and probe response */
1129 	beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1130 
1131 	/* check if we need to merge IBSS */
1132 
1133 	/* not an IBSS */
1134 	if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1135 		goto put_bss;
1136 
1137 	/* different channel */
1138 	if (sdata->u.ibss.fixed_channel &&
1139 	    sdata->u.ibss.chandef.chan != cbss->channel)
1140 		goto put_bss;
1141 
1142 	/* different SSID */
1143 	if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1144 	    memcmp(elems->ssid, sdata->u.ibss.ssid,
1145 				sdata->u.ibss.ssid_len))
1146 		goto put_bss;
1147 
1148 	/* process channel switch */
1149 	if (sdata->vif.csa_active ||
1150 	    ieee80211_ibss_process_chanswitch(sdata, elems, true))
1151 		goto put_bss;
1152 
1153 	/* same BSSID */
1154 	if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1155 		goto put_bss;
1156 
1157 	/* we use a fixed BSSID */
1158 	if (sdata->u.ibss.fixed_bssid)
1159 		goto put_bss;
1160 
1161 	if (ieee80211_have_rx_timestamp(rx_status)) {
1162 		/* time when timestamp field was received */
1163 		rx_timestamp =
1164 			ieee80211_calculate_rx_timestamp(local, rx_status,
1165 							 len + FCS_LEN, 24);
1166 	} else {
1167 		/*
1168 		 * second best option: get current TSF
1169 		 * (will return -1 if not supported)
1170 		 */
1171 		rx_timestamp = drv_get_tsf(local, sdata);
1172 	}
1173 
1174 	ibss_dbg(sdata,
1175 		 "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
1176 		 mgmt->sa, mgmt->bssid,
1177 		 (unsigned long long)rx_timestamp,
1178 		 (unsigned long long)beacon_timestamp,
1179 		 (unsigned long long)(rx_timestamp - beacon_timestamp),
1180 		 jiffies);
1181 
1182 	if (beacon_timestamp > rx_timestamp) {
1183 		ibss_dbg(sdata,
1184 			 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1185 			 mgmt->bssid);
1186 		ieee80211_sta_join_ibss(sdata, bss);
1187 		supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1188 		ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1189 				       supp_rates);
1190 		rcu_read_unlock();
1191 	}
1192 
1193  put_bss:
1194 	ieee80211_rx_bss_put(local, bss);
1195 }
1196 
1197 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1198 			      const u8 *bssid, const u8 *addr,
1199 			      u32 supp_rates)
1200 {
1201 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1202 	struct ieee80211_local *local = sdata->local;
1203 	struct sta_info *sta;
1204 	struct ieee80211_chanctx_conf *chanctx_conf;
1205 	struct ieee80211_supported_band *sband;
1206 	enum nl80211_bss_scan_width scan_width;
1207 	int band;
1208 
1209 	/*
1210 	 * XXX: Consider removing the least recently used entry and
1211 	 * 	allow new one to be added.
1212 	 */
1213 	if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1214 		net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1215 				    sdata->name, addr);
1216 		return;
1217 	}
1218 
1219 	if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1220 		return;
1221 
1222 	if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1223 		return;
1224 
1225 	rcu_read_lock();
1226 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1227 	if (WARN_ON_ONCE(!chanctx_conf)) {
1228 		rcu_read_unlock();
1229 		return;
1230 	}
1231 	band = chanctx_conf->def.chan->band;
1232 	scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1233 	rcu_read_unlock();
1234 
1235 	sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1236 	if (!sta)
1237 		return;
1238 
1239 	sta->rx_stats.last_rx = jiffies;
1240 
1241 	/* make sure mandatory rates are always added */
1242 	sband = local->hw.wiphy->bands[band];
1243 	sta->sta.supp_rates[band] = supp_rates |
1244 			ieee80211_mandatory_rates(sband, scan_width);
1245 
1246 	spin_lock(&ifibss->incomplete_lock);
1247 	list_add(&sta->list, &ifibss->incomplete_stations);
1248 	spin_unlock(&ifibss->incomplete_lock);
1249 	ieee80211_queue_work(&local->hw, &sdata->work);
1250 }
1251 
1252 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1253 {
1254 	struct ieee80211_local *local = sdata->local;
1255 	struct sta_info *sta, *tmp;
1256 	unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1257 	unsigned long exp_rsn = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1258 
1259 	mutex_lock(&local->sta_mtx);
1260 
1261 	list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1262 		if (sdata != sta->sdata)
1263 			continue;
1264 
1265 		if (time_after(jiffies, sta->rx_stats.last_rx + exp_time) ||
1266 		    (time_after(jiffies, sta->rx_stats.last_rx + exp_rsn) &&
1267 		     sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1268 			sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1269 				sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1270 				"not authorized " : "", sta->sta.addr);
1271 
1272 			WARN_ON(__sta_info_destroy(sta));
1273 		}
1274 	}
1275 
1276 	mutex_unlock(&local->sta_mtx);
1277 }
1278 
1279 /*
1280  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1281  */
1282 
1283 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1284 {
1285 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1286 	enum nl80211_bss_scan_width scan_width;
1287 
1288 	sdata_assert_lock(sdata);
1289 
1290 	mod_timer(&ifibss->timer,
1291 		  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1292 
1293 	ieee80211_ibss_sta_expire(sdata);
1294 
1295 	if (time_before(jiffies, ifibss->last_scan_completed +
1296 		       IEEE80211_IBSS_MERGE_INTERVAL))
1297 		return;
1298 
1299 	if (ieee80211_sta_active_ibss(sdata))
1300 		return;
1301 
1302 	if (ifibss->fixed_channel)
1303 		return;
1304 
1305 	sdata_info(sdata,
1306 		   "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1307 
1308 	scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1309 	ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1310 				    NULL, 0, scan_width);
1311 }
1312 
1313 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1314 {
1315 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1316 	u8 bssid[ETH_ALEN];
1317 	u16 capability;
1318 	int i;
1319 
1320 	sdata_assert_lock(sdata);
1321 
1322 	if (ifibss->fixed_bssid) {
1323 		memcpy(bssid, ifibss->bssid, ETH_ALEN);
1324 	} else {
1325 		/* Generate random, not broadcast, locally administered BSSID. Mix in
1326 		 * own MAC address to make sure that devices that do not have proper
1327 		 * random number generator get different BSSID. */
1328 		get_random_bytes(bssid, ETH_ALEN);
1329 		for (i = 0; i < ETH_ALEN; i++)
1330 			bssid[i] ^= sdata->vif.addr[i];
1331 		bssid[0] &= ~0x01;
1332 		bssid[0] |= 0x02;
1333 	}
1334 
1335 	sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1336 
1337 	capability = WLAN_CAPABILITY_IBSS;
1338 
1339 	if (ifibss->privacy)
1340 		capability |= WLAN_CAPABILITY_PRIVACY;
1341 
1342 	__ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1343 				  &ifibss->chandef, ifibss->basic_rates,
1344 				  capability, 0, true);
1345 }
1346 
1347 static unsigned ibss_setup_channels(struct wiphy *wiphy,
1348 				    struct ieee80211_channel **channels,
1349 				    unsigned int channels_max,
1350 				    u32 center_freq, u32 width)
1351 {
1352 	struct ieee80211_channel *chan = NULL;
1353 	unsigned int n_chan = 0;
1354 	u32 start_freq, end_freq, freq;
1355 
1356 	if (width <= 20) {
1357 		start_freq = center_freq;
1358 		end_freq = center_freq;
1359 	} else {
1360 		start_freq = center_freq - width / 2 + 10;
1361 		end_freq = center_freq + width / 2 - 10;
1362 	}
1363 
1364 	for (freq = start_freq; freq <= end_freq; freq += 20) {
1365 		chan = ieee80211_get_channel(wiphy, freq);
1366 		if (!chan)
1367 			continue;
1368 		if (n_chan >= channels_max)
1369 			return n_chan;
1370 
1371 		channels[n_chan] = chan;
1372 		n_chan++;
1373 	}
1374 
1375 	return n_chan;
1376 }
1377 
1378 static unsigned int
1379 ieee80211_ibss_setup_scan_channels(struct wiphy *wiphy,
1380 				   const struct cfg80211_chan_def *chandef,
1381 				   struct ieee80211_channel **channels,
1382 				   unsigned int channels_max)
1383 {
1384 	unsigned int n_chan = 0;
1385 	u32 width, cf1, cf2 = 0;
1386 
1387 	switch (chandef->width) {
1388 	case NL80211_CHAN_WIDTH_40:
1389 		width = 40;
1390 		break;
1391 	case NL80211_CHAN_WIDTH_80P80:
1392 		cf2 = chandef->center_freq2;
1393 		/* fall through */
1394 	case NL80211_CHAN_WIDTH_80:
1395 		width = 80;
1396 		break;
1397 	case NL80211_CHAN_WIDTH_160:
1398 		width = 160;
1399 		break;
1400 	default:
1401 		width = 20;
1402 		break;
1403 	}
1404 
1405 	cf1 = chandef->center_freq1;
1406 
1407 	n_chan = ibss_setup_channels(wiphy, channels, channels_max, cf1, width);
1408 
1409 	if (cf2)
1410 		n_chan += ibss_setup_channels(wiphy, &channels[n_chan],
1411 					      channels_max - n_chan, cf2,
1412 					      width);
1413 
1414 	return n_chan;
1415 }
1416 
1417 /*
1418  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1419  */
1420 
1421 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1422 {
1423 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1424 	struct ieee80211_local *local = sdata->local;
1425 	struct cfg80211_bss *cbss;
1426 	struct ieee80211_channel *chan = NULL;
1427 	const u8 *bssid = NULL;
1428 	enum nl80211_bss_scan_width scan_width;
1429 	int active_ibss;
1430 
1431 	sdata_assert_lock(sdata);
1432 
1433 	active_ibss = ieee80211_sta_active_ibss(sdata);
1434 	ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1435 
1436 	if (active_ibss)
1437 		return;
1438 
1439 	if (ifibss->fixed_bssid)
1440 		bssid = ifibss->bssid;
1441 	if (ifibss->fixed_channel)
1442 		chan = ifibss->chandef.chan;
1443 	if (!is_zero_ether_addr(ifibss->bssid))
1444 		bssid = ifibss->bssid;
1445 	cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1446 				ifibss->ssid, ifibss->ssid_len,
1447 				IEEE80211_BSS_TYPE_IBSS,
1448 				IEEE80211_PRIVACY(ifibss->privacy));
1449 
1450 	if (cbss) {
1451 		struct ieee80211_bss *bss;
1452 
1453 		bss = (void *)cbss->priv;
1454 		ibss_dbg(sdata,
1455 			 "sta_find_ibss: selected %pM current %pM\n",
1456 			 cbss->bssid, ifibss->bssid);
1457 		sdata_info(sdata,
1458 			   "Selected IBSS BSSID %pM based on configured SSID\n",
1459 			   cbss->bssid);
1460 
1461 		ieee80211_sta_join_ibss(sdata, bss);
1462 		ieee80211_rx_bss_put(local, bss);
1463 		return;
1464 	}
1465 
1466 	/* if a fixed bssid and a fixed freq have been provided create the IBSS
1467 	 * directly and do not waste time scanning
1468 	 */
1469 	if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1470 		sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1471 			   bssid);
1472 		ieee80211_sta_create_ibss(sdata);
1473 		return;
1474 	}
1475 
1476 
1477 	ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1478 
1479 	/* Selected IBSS not found in current scan results - try to scan */
1480 	if (time_after(jiffies, ifibss->last_scan_completed +
1481 					IEEE80211_SCAN_INTERVAL)) {
1482 		struct ieee80211_channel *channels[8];
1483 		unsigned int num;
1484 
1485 		sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1486 
1487 		scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1488 
1489 		if (ifibss->fixed_channel) {
1490 			num = ieee80211_ibss_setup_scan_channels(local->hw.wiphy,
1491 								 &ifibss->chandef,
1492 								 channels,
1493 								 ARRAY_SIZE(channels));
1494 			ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1495 						    ifibss->ssid_len, channels,
1496 						    num, scan_width);
1497 		} else {
1498 			ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1499 						    ifibss->ssid_len, NULL,
1500 						    0, scan_width);
1501 		}
1502 	} else {
1503 		int interval = IEEE80211_SCAN_INTERVAL;
1504 
1505 		if (time_after(jiffies, ifibss->ibss_join_req +
1506 			       IEEE80211_IBSS_JOIN_TIMEOUT))
1507 			ieee80211_sta_create_ibss(sdata);
1508 
1509 		mod_timer(&ifibss->timer,
1510 			  round_jiffies(jiffies + interval));
1511 	}
1512 }
1513 
1514 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1515 					struct sk_buff *req)
1516 {
1517 	struct ieee80211_mgmt *mgmt = (void *)req->data;
1518 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1519 	struct ieee80211_local *local = sdata->local;
1520 	int tx_last_beacon, len = req->len;
1521 	struct sk_buff *skb;
1522 	struct beacon_data *presp;
1523 	u8 *pos, *end;
1524 
1525 	sdata_assert_lock(sdata);
1526 
1527 	presp = rcu_dereference_protected(ifibss->presp,
1528 					  lockdep_is_held(&sdata->wdev.mtx));
1529 
1530 	if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1531 	    len < 24 + 2 || !presp)
1532 		return;
1533 
1534 	tx_last_beacon = drv_tx_last_beacon(local);
1535 
1536 	ibss_dbg(sdata,
1537 		 "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
1538 		 mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
1539 
1540 	if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1541 		return;
1542 
1543 	if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1544 	    !is_broadcast_ether_addr(mgmt->bssid))
1545 		return;
1546 
1547 	end = ((u8 *) mgmt) + len;
1548 	pos = mgmt->u.probe_req.variable;
1549 	if (pos[0] != WLAN_EID_SSID ||
1550 	    pos + 2 + pos[1] > end) {
1551 		ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1552 			 mgmt->sa);
1553 		return;
1554 	}
1555 	if (pos[1] != 0 &&
1556 	    (pos[1] != ifibss->ssid_len ||
1557 	     memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1558 		/* Ignore ProbeReq for foreign SSID */
1559 		return;
1560 	}
1561 
1562 	/* Reply with ProbeResp */
1563 	skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1564 	if (!skb)
1565 		return;
1566 
1567 	skb_reserve(skb, local->tx_headroom);
1568 	memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
1569 
1570 	memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1571 	ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1572 	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1573 
1574 	/* avoid excessive retries for probe request to wildcard SSIDs */
1575 	if (pos[1] == 0)
1576 		IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1577 
1578 	ieee80211_tx_skb(sdata, skb);
1579 }
1580 
1581 static
1582 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1583 				    struct ieee80211_mgmt *mgmt, size_t len,
1584 				    struct ieee80211_rx_status *rx_status)
1585 {
1586 	size_t baselen;
1587 	struct ieee802_11_elems elems;
1588 
1589 	BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1590 		     offsetof(typeof(mgmt->u.beacon), variable));
1591 
1592 	/*
1593 	 * either beacon or probe_resp but the variable field is at the
1594 	 * same offset
1595 	 */
1596 	baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1597 	if (baselen > len)
1598 		return;
1599 
1600 	ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1601 			       false, &elems);
1602 
1603 	ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1604 }
1605 
1606 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1607 				   struct sk_buff *skb)
1608 {
1609 	struct ieee80211_rx_status *rx_status;
1610 	struct ieee80211_mgmt *mgmt;
1611 	u16 fc;
1612 	struct ieee802_11_elems elems;
1613 	int ies_len;
1614 
1615 	rx_status = IEEE80211_SKB_RXCB(skb);
1616 	mgmt = (struct ieee80211_mgmt *) skb->data;
1617 	fc = le16_to_cpu(mgmt->frame_control);
1618 
1619 	sdata_lock(sdata);
1620 
1621 	if (!sdata->u.ibss.ssid_len)
1622 		goto mgmt_out; /* not ready to merge yet */
1623 
1624 	switch (fc & IEEE80211_FCTL_STYPE) {
1625 	case IEEE80211_STYPE_PROBE_REQ:
1626 		ieee80211_rx_mgmt_probe_req(sdata, skb);
1627 		break;
1628 	case IEEE80211_STYPE_PROBE_RESP:
1629 	case IEEE80211_STYPE_BEACON:
1630 		ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1631 					       rx_status);
1632 		break;
1633 	case IEEE80211_STYPE_AUTH:
1634 		ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1635 		break;
1636 	case IEEE80211_STYPE_DEAUTH:
1637 		ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1638 		break;
1639 	case IEEE80211_STYPE_ACTION:
1640 		switch (mgmt->u.action.category) {
1641 		case WLAN_CATEGORY_SPECTRUM_MGMT:
1642 			ies_len = skb->len -
1643 				  offsetof(struct ieee80211_mgmt,
1644 					   u.action.u.chan_switch.variable);
1645 
1646 			if (ies_len < 0)
1647 				break;
1648 
1649 			ieee802_11_parse_elems(
1650 				mgmt->u.action.u.chan_switch.variable,
1651 				ies_len, true, &elems);
1652 
1653 			if (elems.parse_error)
1654 				break;
1655 
1656 			ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1657 							rx_status, &elems);
1658 			break;
1659 		}
1660 	}
1661 
1662  mgmt_out:
1663 	sdata_unlock(sdata);
1664 }
1665 
1666 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1667 {
1668 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1669 	struct sta_info *sta;
1670 
1671 	sdata_lock(sdata);
1672 
1673 	/*
1674 	 * Work could be scheduled after scan or similar
1675 	 * when we aren't even joined (or trying) with a
1676 	 * network.
1677 	 */
1678 	if (!ifibss->ssid_len)
1679 		goto out;
1680 
1681 	spin_lock_bh(&ifibss->incomplete_lock);
1682 	while (!list_empty(&ifibss->incomplete_stations)) {
1683 		sta = list_first_entry(&ifibss->incomplete_stations,
1684 				       struct sta_info, list);
1685 		list_del(&sta->list);
1686 		spin_unlock_bh(&ifibss->incomplete_lock);
1687 
1688 		ieee80211_ibss_finish_sta(sta);
1689 		rcu_read_unlock();
1690 		spin_lock_bh(&ifibss->incomplete_lock);
1691 	}
1692 	spin_unlock_bh(&ifibss->incomplete_lock);
1693 
1694 	switch (ifibss->state) {
1695 	case IEEE80211_IBSS_MLME_SEARCH:
1696 		ieee80211_sta_find_ibss(sdata);
1697 		break;
1698 	case IEEE80211_IBSS_MLME_JOINED:
1699 		ieee80211_sta_merge_ibss(sdata);
1700 		break;
1701 	default:
1702 		WARN_ON(1);
1703 		break;
1704 	}
1705 
1706  out:
1707 	sdata_unlock(sdata);
1708 }
1709 
1710 static void ieee80211_ibss_timer(unsigned long data)
1711 {
1712 	struct ieee80211_sub_if_data *sdata =
1713 		(struct ieee80211_sub_if_data *) data;
1714 
1715 	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1716 }
1717 
1718 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1719 {
1720 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1721 
1722 	setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1723 		    (unsigned long) sdata);
1724 	INIT_LIST_HEAD(&ifibss->incomplete_stations);
1725 	spin_lock_init(&ifibss->incomplete_lock);
1726 	INIT_WORK(&ifibss->csa_connection_drop_work,
1727 		  ieee80211_csa_connection_drop_work);
1728 }
1729 
1730 /* scan finished notification */
1731 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1732 {
1733 	struct ieee80211_sub_if_data *sdata;
1734 
1735 	mutex_lock(&local->iflist_mtx);
1736 	list_for_each_entry(sdata, &local->interfaces, list) {
1737 		if (!ieee80211_sdata_running(sdata))
1738 			continue;
1739 		if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1740 			continue;
1741 		sdata->u.ibss.last_scan_completed = jiffies;
1742 	}
1743 	mutex_unlock(&local->iflist_mtx);
1744 }
1745 
1746 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1747 			struct cfg80211_ibss_params *params)
1748 {
1749 	u32 changed = 0;
1750 	u32 rate_flags;
1751 	struct ieee80211_supported_band *sband;
1752 	enum ieee80211_chanctx_mode chanmode;
1753 	struct ieee80211_local *local = sdata->local;
1754 	int radar_detect_width = 0;
1755 	int i;
1756 	int ret;
1757 
1758 	ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1759 					    &params->chandef,
1760 					    sdata->wdev.iftype);
1761 	if (ret < 0)
1762 		return ret;
1763 
1764 	if (ret > 0) {
1765 		if (!params->userspace_handles_dfs)
1766 			return -EINVAL;
1767 		radar_detect_width = BIT(params->chandef.width);
1768 	}
1769 
1770 	chanmode = (params->channel_fixed && !ret) ?
1771 		IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE;
1772 
1773 	mutex_lock(&local->chanctx_mtx);
1774 	ret = ieee80211_check_combinations(sdata, &params->chandef, chanmode,
1775 					   radar_detect_width);
1776 	mutex_unlock(&local->chanctx_mtx);
1777 	if (ret < 0)
1778 		return ret;
1779 
1780 	if (params->bssid) {
1781 		memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1782 		sdata->u.ibss.fixed_bssid = true;
1783 	} else
1784 		sdata->u.ibss.fixed_bssid = false;
1785 
1786 	sdata->u.ibss.privacy = params->privacy;
1787 	sdata->u.ibss.control_port = params->control_port;
1788 	sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1789 	sdata->u.ibss.basic_rates = params->basic_rates;
1790 	sdata->u.ibss.last_scan_completed = jiffies;
1791 
1792 	/* fix basic_rates if channel does not support these rates */
1793 	rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1794 	sband = local->hw.wiphy->bands[params->chandef.chan->band];
1795 	for (i = 0; i < sband->n_bitrates; i++) {
1796 		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1797 			sdata->u.ibss.basic_rates &= ~BIT(i);
1798 	}
1799 	memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1800 	       sizeof(params->mcast_rate));
1801 
1802 	sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1803 
1804 	sdata->u.ibss.chandef = params->chandef;
1805 	sdata->u.ibss.fixed_channel = params->channel_fixed;
1806 
1807 	if (params->ie) {
1808 		sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1809 					   GFP_KERNEL);
1810 		if (sdata->u.ibss.ie)
1811 			sdata->u.ibss.ie_len = params->ie_len;
1812 	}
1813 
1814 	sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1815 	sdata->u.ibss.ibss_join_req = jiffies;
1816 
1817 	memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1818 	sdata->u.ibss.ssid_len = params->ssid_len;
1819 
1820 	memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1821 	       sizeof(sdata->u.ibss.ht_capa));
1822 	memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1823 	       sizeof(sdata->u.ibss.ht_capa_mask));
1824 
1825 	/*
1826 	 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1827 	 * reserved, but an HT STA shall protect HT transmissions as though
1828 	 * the HT Protection field were set to non-HT mixed mode.
1829 	 *
1830 	 * In an IBSS, the RIFS Mode field of the HT Operation element is
1831 	 * also reserved, but an HT STA shall operate as though this field
1832 	 * were set to 1.
1833 	 */
1834 
1835 	sdata->vif.bss_conf.ht_operation_mode |=
1836 		  IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1837 		| IEEE80211_HT_PARAM_RIFS_MODE;
1838 
1839 	changed |= BSS_CHANGED_HT;
1840 	ieee80211_bss_info_change_notify(sdata, changed);
1841 
1842 	sdata->smps_mode = IEEE80211_SMPS_OFF;
1843 	sdata->needed_rx_chains = local->rx_chains;
1844 
1845 	ieee80211_queue_work(&local->hw, &sdata->work);
1846 
1847 	return 0;
1848 }
1849 
1850 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1851 {
1852 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1853 
1854 	ieee80211_ibss_disconnect(sdata);
1855 	ifibss->ssid_len = 0;
1856 	eth_zero_addr(ifibss->bssid);
1857 
1858 	/* remove beacon */
1859 	kfree(sdata->u.ibss.ie);
1860 
1861 	/* on the next join, re-program HT parameters */
1862 	memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1863 	memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1864 
1865 	synchronize_rcu();
1866 
1867 	skb_queue_purge(&sdata->skb_queue);
1868 
1869 	del_timer_sync(&sdata->u.ibss.timer);
1870 
1871 	return 0;
1872 }
1873