xref: /linux/net/mac80211/ibss.c (revision 5ee2d63ca1201ed23c6595cb2fc927222215bce3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * IBSS mode implementation
4  * Copyright 2003-2008, Jouni Malinen <j@w1.fi>
5  * Copyright 2004, Instant802 Networks, Inc.
6  * Copyright 2005, Devicescape Software, Inc.
7  * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
8  * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
9  * Copyright 2009, Johannes Berg <johannes@sipsolutions.net>
10  * Copyright 2013-2014  Intel Mobile Communications GmbH
11  * Copyright(c) 2016 Intel Deutschland GmbH
12  * Copyright(c) 2018-2024 Intel Corporation
13  */
14 
15 #include <linux/delay.h>
16 #include <linux/slab.h>
17 #include <linux/if_ether.h>
18 #include <linux/skbuff.h>
19 #include <linux/if_arp.h>
20 #include <linux/etherdevice.h>
21 #include <linux/rtnetlink.h>
22 #include <net/mac80211.h>
23 
24 #include "ieee80211_i.h"
25 #include "driver-ops.h"
26 #include "rate.h"
27 
28 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
29 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
30 
31 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
32 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
33 #define IEEE80211_IBSS_RSN_INACTIVITY_LIMIT (10 * HZ)
34 
35 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
36 
37 static struct beacon_data *
38 ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
39 			   const int beacon_int, const u32 basic_rates,
40 			   const u16 capability, u64 tsf,
41 			   struct cfg80211_chan_def *chandef,
42 			   bool *have_higher_than_11mbit,
43 			   struct cfg80211_csa_settings *csa_settings)
44 {
45 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
46 	struct ieee80211_local *local = sdata->local;
47 	int rates_n = 0, i, ri;
48 	struct ieee80211_mgmt *mgmt;
49 	u8 *pos;
50 	struct ieee80211_supported_band *sband;
51 	u32 rate_flags, rates = 0, rates_added = 0;
52 	struct beacon_data *presp;
53 	int frame_len;
54 
55 	/* Build IBSS probe response */
56 	frame_len = sizeof(struct ieee80211_hdr_3addr) +
57 		    12 /* struct ieee80211_mgmt.u.beacon */ +
58 		    2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
59 		    2 + 8 /* max Supported Rates */ +
60 		    3 /* max DS params */ +
61 		    4 /* IBSS params */ +
62 		    5 /* Channel Switch Announcement */ +
63 		    2 + (IEEE80211_MAX_SUPP_RATES - 8) +
64 		    2 + sizeof(struct ieee80211_ht_cap) +
65 		    2 + sizeof(struct ieee80211_ht_operation) +
66 		    2 + sizeof(struct ieee80211_vht_cap) +
67 		    2 + sizeof(struct ieee80211_vht_operation) +
68 		    ifibss->ie_len;
69 	presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
70 	if (!presp)
71 		return NULL;
72 
73 	presp->head = (void *)(presp + 1);
74 
75 	mgmt = (void *) presp->head;
76 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
77 					  IEEE80211_STYPE_PROBE_RESP);
78 	eth_broadcast_addr(mgmt->da);
79 	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
80 	memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
81 	mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
82 	mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
83 	mgmt->u.beacon.capab_info = cpu_to_le16(capability);
84 
85 	pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
86 
87 	*pos++ = WLAN_EID_SSID;
88 	*pos++ = ifibss->ssid_len;
89 	memcpy(pos, ifibss->ssid, ifibss->ssid_len);
90 	pos += ifibss->ssid_len;
91 
92 	sband = local->hw.wiphy->bands[chandef->chan->band];
93 	rate_flags = ieee80211_chandef_rate_flags(chandef);
94 	rates_n = 0;
95 	if (have_higher_than_11mbit)
96 		*have_higher_than_11mbit = false;
97 
98 	for (i = 0; i < sband->n_bitrates; i++) {
99 		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
100 			continue;
101 		if (sband->bitrates[i].bitrate > 110 &&
102 		    have_higher_than_11mbit)
103 			*have_higher_than_11mbit = true;
104 
105 		rates |= BIT(i);
106 		rates_n++;
107 	}
108 
109 	*pos++ = WLAN_EID_SUPP_RATES;
110 	*pos++ = min_t(int, 8, rates_n);
111 	for (ri = 0; ri < sband->n_bitrates; ri++) {
112 		int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate, 5);
113 		u8 basic = 0;
114 		if (!(rates & BIT(ri)))
115 			continue;
116 
117 		if (basic_rates & BIT(ri))
118 			basic = 0x80;
119 		*pos++ = basic | (u8) rate;
120 		if (++rates_added == 8) {
121 			ri++; /* continue at next rate for EXT_SUPP_RATES */
122 			break;
123 		}
124 	}
125 
126 	if (sband->band == NL80211_BAND_2GHZ) {
127 		*pos++ = WLAN_EID_DS_PARAMS;
128 		*pos++ = 1;
129 		*pos++ = ieee80211_frequency_to_channel(
130 				chandef->chan->center_freq);
131 	}
132 
133 	*pos++ = WLAN_EID_IBSS_PARAMS;
134 	*pos++ = 2;
135 	/* FIX: set ATIM window based on scan results */
136 	*pos++ = 0;
137 	*pos++ = 0;
138 
139 	if (csa_settings) {
140 		*pos++ = WLAN_EID_CHANNEL_SWITCH;
141 		*pos++ = 3;
142 		*pos++ = csa_settings->block_tx ? 1 : 0;
143 		*pos++ = ieee80211_frequency_to_channel(
144 				csa_settings->chandef.chan->center_freq);
145 		presp->cntdwn_counter_offsets[0] = (pos - presp->head);
146 		*pos++ = csa_settings->count;
147 		presp->cntdwn_current_counter = csa_settings->count;
148 	}
149 
150 	/* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
151 	if (rates_n > 8) {
152 		*pos++ = WLAN_EID_EXT_SUPP_RATES;
153 		*pos++ = rates_n - 8;
154 		for (; ri < sband->n_bitrates; ri++) {
155 			int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate, 5);
156 			u8 basic = 0;
157 			if (!(rates & BIT(ri)))
158 				continue;
159 
160 			if (basic_rates & BIT(ri))
161 				basic = 0x80;
162 			*pos++ = basic | (u8) rate;
163 		}
164 	}
165 
166 	if (ifibss->ie_len) {
167 		memcpy(pos, ifibss->ie, ifibss->ie_len);
168 		pos += ifibss->ie_len;
169 	}
170 
171 	/* add HT capability and information IEs */
172 	if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT &&
173 	    chandef->width != NL80211_CHAN_WIDTH_5 &&
174 	    chandef->width != NL80211_CHAN_WIDTH_10 &&
175 	    sband->ht_cap.ht_supported) {
176 		struct ieee80211_sta_ht_cap ht_cap;
177 
178 		memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
179 		ieee80211_apply_htcap_overrides(sdata, &ht_cap);
180 
181 		pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
182 		/*
183 		 * Note: According to 802.11n-2009 9.13.3.1, HT Protection
184 		 * field and RIFS Mode are reserved in IBSS mode, therefore
185 		 * keep them at 0
186 		 */
187 		pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
188 						 chandef, 0, false);
189 
190 		/* add VHT capability and information IEs */
191 		if (chandef->width != NL80211_CHAN_WIDTH_20 &&
192 		    chandef->width != NL80211_CHAN_WIDTH_40 &&
193 		    sband->vht_cap.vht_supported) {
194 			pos = ieee80211_ie_build_vht_cap(pos, &sband->vht_cap,
195 							 sband->vht_cap.cap);
196 			pos = ieee80211_ie_build_vht_oper(pos, &sband->vht_cap,
197 							  chandef);
198 		}
199 	}
200 
201 	if (local->hw.queues >= IEEE80211_NUM_ACS)
202 		pos = ieee80211_add_wmm_info_ie(pos, 0); /* U-APSD not in use */
203 
204 	presp->head_len = pos - presp->head;
205 	if (WARN_ON(presp->head_len > frame_len))
206 		goto error;
207 
208 	return presp;
209 error:
210 	kfree(presp);
211 	return NULL;
212 }
213 
214 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
215 				      const u8 *bssid, const int beacon_int,
216 				      struct cfg80211_chan_def *req_chandef,
217 				      const u32 basic_rates,
218 				      const u16 capability, u64 tsf,
219 				      bool creator)
220 {
221 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
222 	struct ieee80211_local *local = sdata->local;
223 	struct ieee80211_mgmt *mgmt;
224 	struct cfg80211_bss *bss;
225 	u64 bss_change;
226 	struct ieee80211_chan_req chanreq = {};
227 	struct ieee80211_channel *chan;
228 	struct beacon_data *presp;
229 	struct cfg80211_inform_bss bss_meta = {};
230 	bool have_higher_than_11mbit;
231 	bool radar_required;
232 	int err;
233 
234 	lockdep_assert_wiphy(local->hw.wiphy);
235 
236 	/* Reset own TSF to allow time synchronization work. */
237 	drv_reset_tsf(local, sdata);
238 
239 	if (!ether_addr_equal(ifibss->bssid, bssid))
240 		sta_info_flush(sdata, -1);
241 
242 	/* if merging, indicate to driver that we leave the old IBSS */
243 	if (sdata->vif.cfg.ibss_joined) {
244 		sdata->vif.cfg.ibss_joined = false;
245 		sdata->vif.cfg.ibss_creator = false;
246 		sdata->vif.bss_conf.enable_beacon = false;
247 		netif_carrier_off(sdata->dev);
248 		ieee80211_bss_info_change_notify(sdata,
249 						 BSS_CHANGED_IBSS |
250 						 BSS_CHANGED_BEACON_ENABLED);
251 		drv_leave_ibss(local, sdata);
252 	}
253 
254 	presp = sdata_dereference(ifibss->presp, sdata);
255 	RCU_INIT_POINTER(ifibss->presp, NULL);
256 	if (presp)
257 		kfree_rcu(presp, rcu_head);
258 
259 	/* make a copy of the chandef, it could be modified below. */
260 	chanreq.oper = *req_chandef;
261 	chan = chanreq.oper.chan;
262 	if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chanreq.oper,
263 				     NL80211_IFTYPE_ADHOC)) {
264 		if (chanreq.oper.width == NL80211_CHAN_WIDTH_5 ||
265 		    chanreq.oper.width == NL80211_CHAN_WIDTH_10 ||
266 		    chanreq.oper.width == NL80211_CHAN_WIDTH_20_NOHT ||
267 		    chanreq.oper.width == NL80211_CHAN_WIDTH_20) {
268 			sdata_info(sdata,
269 				   "Failed to join IBSS, beacons forbidden\n");
270 			return;
271 		}
272 		chanreq.oper.width = NL80211_CHAN_WIDTH_20;
273 		chanreq.oper.center_freq1 = chan->center_freq;
274 		/* check again for downgraded chandef */
275 		if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chanreq.oper,
276 					     NL80211_IFTYPE_ADHOC)) {
277 			sdata_info(sdata,
278 				   "Failed to join IBSS, beacons forbidden\n");
279 			return;
280 		}
281 	}
282 
283 	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
284 					    &chanreq.oper, NL80211_IFTYPE_ADHOC);
285 	if (err < 0) {
286 		sdata_info(sdata,
287 			   "Failed to join IBSS, invalid chandef\n");
288 		return;
289 	}
290 	if (err > 0 && !ifibss->userspace_handles_dfs) {
291 		sdata_info(sdata,
292 			   "Failed to join IBSS, DFS channel without control program\n");
293 		return;
294 	}
295 
296 	radar_required = err;
297 
298 	if (ieee80211_link_use_channel(&sdata->deflink, &chanreq,
299 				       ifibss->fixed_channel ?
300 					IEEE80211_CHANCTX_SHARED :
301 					IEEE80211_CHANCTX_EXCLUSIVE)) {
302 		sdata_info(sdata, "Failed to join IBSS, no channel context\n");
303 		return;
304 	}
305 	sdata->deflink.radar_required = radar_required;
306 
307 	memcpy(ifibss->bssid, bssid, ETH_ALEN);
308 
309 	presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
310 					   capability, tsf, &chanreq.oper,
311 					   &have_higher_than_11mbit, NULL);
312 	if (!presp)
313 		return;
314 
315 	rcu_assign_pointer(ifibss->presp, presp);
316 	mgmt = (void *)presp->head;
317 
318 	sdata->vif.bss_conf.enable_beacon = true;
319 	sdata->vif.bss_conf.beacon_int = beacon_int;
320 	sdata->vif.bss_conf.basic_rates = basic_rates;
321 	sdata->vif.cfg.ssid_len = ifibss->ssid_len;
322 	memcpy(sdata->vif.cfg.ssid, ifibss->ssid, ifibss->ssid_len);
323 	bss_change = BSS_CHANGED_BEACON_INT;
324 	bss_change |= ieee80211_reset_erp_info(sdata);
325 	bss_change |= BSS_CHANGED_BSSID;
326 	bss_change |= BSS_CHANGED_BEACON;
327 	bss_change |= BSS_CHANGED_BEACON_ENABLED;
328 	bss_change |= BSS_CHANGED_BASIC_RATES;
329 	bss_change |= BSS_CHANGED_HT;
330 	bss_change |= BSS_CHANGED_IBSS;
331 	bss_change |= BSS_CHANGED_SSID;
332 
333 	/*
334 	 * In 5 GHz/802.11a, we can always use short slot time.
335 	 * (IEEE 802.11-2012 18.3.8.7)
336 	 *
337 	 * In 2.4GHz, we must always use long slots in IBSS for compatibility
338 	 * reasons.
339 	 * (IEEE 802.11-2012 19.4.5)
340 	 *
341 	 * HT follows these specifications (IEEE 802.11-2012 20.3.18)
342 	 */
343 	sdata->vif.bss_conf.use_short_slot = chan->band == NL80211_BAND_5GHZ;
344 	bss_change |= BSS_CHANGED_ERP_SLOT;
345 
346 	/* cf. IEEE 802.11 9.2.12 */
347 	sdata->deflink.operating_11g_mode =
348 		chan->band == NL80211_BAND_2GHZ && have_higher_than_11mbit;
349 
350 	ieee80211_set_wmm_default(&sdata->deflink, true, false);
351 
352 	sdata->vif.cfg.ibss_joined = true;
353 	sdata->vif.cfg.ibss_creator = creator;
354 
355 	err = drv_join_ibss(local, sdata);
356 	if (err) {
357 		sdata->vif.cfg.ibss_joined = false;
358 		sdata->vif.cfg.ibss_creator = false;
359 		sdata->vif.bss_conf.enable_beacon = false;
360 		sdata->vif.cfg.ssid_len = 0;
361 		RCU_INIT_POINTER(ifibss->presp, NULL);
362 		kfree_rcu(presp, rcu_head);
363 		ieee80211_link_release_channel(&sdata->deflink);
364 		sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
365 			   err);
366 		return;
367 	}
368 
369 	ieee80211_bss_info_change_notify(sdata, bss_change);
370 
371 	ifibss->state = IEEE80211_IBSS_MLME_JOINED;
372 	mod_timer(&ifibss->timer,
373 		  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
374 
375 	bss_meta.chan = chan;
376 	bss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta, mgmt,
377 					     presp->head_len, GFP_KERNEL);
378 
379 	cfg80211_put_bss(local->hw.wiphy, bss);
380 	netif_carrier_on(sdata->dev);
381 	cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
382 }
383 
384 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
385 				    struct ieee80211_bss *bss)
386 {
387 	struct cfg80211_bss *cbss =
388 		container_of((void *)bss, struct cfg80211_bss, priv);
389 	struct ieee80211_supported_band *sband;
390 	struct cfg80211_chan_def chandef;
391 	u32 basic_rates;
392 	int i, j;
393 	u16 beacon_int = cbss->beacon_interval;
394 	const struct cfg80211_bss_ies *ies;
395 	enum nl80211_channel_type chan_type;
396 	u64 tsf;
397 	u32 rate_flags;
398 
399 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
400 
401 	if (beacon_int < 10)
402 		beacon_int = 10;
403 
404 	switch (sdata->u.ibss.chandef.width) {
405 	case NL80211_CHAN_WIDTH_20_NOHT:
406 	case NL80211_CHAN_WIDTH_20:
407 	case NL80211_CHAN_WIDTH_40:
408 		chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
409 		cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
410 		break;
411 	case NL80211_CHAN_WIDTH_5:
412 	case NL80211_CHAN_WIDTH_10:
413 		cfg80211_chandef_create(&chandef, cbss->channel,
414 					NL80211_CHAN_NO_HT);
415 		chandef.width = sdata->u.ibss.chandef.width;
416 		break;
417 	case NL80211_CHAN_WIDTH_80:
418 	case NL80211_CHAN_WIDTH_80P80:
419 	case NL80211_CHAN_WIDTH_160:
420 		chandef = sdata->u.ibss.chandef;
421 		chandef.chan = cbss->channel;
422 		break;
423 	default:
424 		/* fall back to 20 MHz for unsupported modes */
425 		cfg80211_chandef_create(&chandef, cbss->channel,
426 					NL80211_CHAN_NO_HT);
427 		break;
428 	}
429 
430 	sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
431 	rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
432 
433 	basic_rates = 0;
434 
435 	for (i = 0; i < bss->supp_rates_len; i++) {
436 		int rate = bss->supp_rates[i] & 0x7f;
437 		bool is_basic = !!(bss->supp_rates[i] & 0x80);
438 
439 		for (j = 0; j < sband->n_bitrates; j++) {
440 			int brate;
441 			if ((rate_flags & sband->bitrates[j].flags)
442 			    != rate_flags)
443 				continue;
444 
445 			brate = DIV_ROUND_UP(sband->bitrates[j].bitrate, 5);
446 			if (brate == rate) {
447 				if (is_basic)
448 					basic_rates |= BIT(j);
449 				break;
450 			}
451 		}
452 	}
453 
454 	rcu_read_lock();
455 	ies = rcu_dereference(cbss->ies);
456 	tsf = ies->tsf;
457 	rcu_read_unlock();
458 
459 	__ieee80211_sta_join_ibss(sdata, cbss->bssid,
460 				  beacon_int,
461 				  &chandef,
462 				  basic_rates,
463 				  cbss->capability,
464 				  tsf, false);
465 }
466 
467 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
468 			      struct cfg80211_csa_settings *csa_settings,
469 			      u64 *changed)
470 {
471 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
472 	struct beacon_data *presp, *old_presp;
473 	struct cfg80211_bss *cbss;
474 	const struct cfg80211_bss_ies *ies;
475 	u16 capability = WLAN_CAPABILITY_IBSS;
476 	u64 tsf;
477 
478 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
479 
480 	if (ifibss->privacy)
481 		capability |= WLAN_CAPABILITY_PRIVACY;
482 
483 	cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
484 				ifibss->bssid, ifibss->ssid,
485 				ifibss->ssid_len, IEEE80211_BSS_TYPE_IBSS,
486 				IEEE80211_PRIVACY(ifibss->privacy));
487 
488 	if (unlikely(!cbss))
489 		return -EINVAL;
490 
491 	rcu_read_lock();
492 	ies = rcu_dereference(cbss->ies);
493 	tsf = ies->tsf;
494 	rcu_read_unlock();
495 	cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
496 
497 	old_presp = sdata_dereference(ifibss->presp, sdata);
498 
499 	presp = ieee80211_ibss_build_presp(sdata,
500 					   sdata->vif.bss_conf.beacon_int,
501 					   sdata->vif.bss_conf.basic_rates,
502 					   capability, tsf, &ifibss->chandef,
503 					   NULL, csa_settings);
504 	if (!presp)
505 		return -ENOMEM;
506 
507 	rcu_assign_pointer(ifibss->presp, presp);
508 	if (old_presp)
509 		kfree_rcu(old_presp, rcu_head);
510 
511 	*changed |= BSS_CHANGED_BEACON;
512 	return 0;
513 }
514 
515 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata, u64 *changed)
516 {
517 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
518 	struct cfg80211_bss *cbss;
519 
520 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
521 
522 	/* When not connected/joined, sending CSA doesn't make sense. */
523 	if (ifibss->state != IEEE80211_IBSS_MLME_JOINED)
524 		return -ENOLINK;
525 
526 	/* update cfg80211 bss information with the new channel */
527 	if (!is_zero_ether_addr(ifibss->bssid)) {
528 		cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
529 					ifibss->chandef.chan,
530 					ifibss->bssid, ifibss->ssid,
531 					ifibss->ssid_len,
532 					IEEE80211_BSS_TYPE_IBSS,
533 					IEEE80211_PRIVACY(ifibss->privacy));
534 		/* XXX: should not really modify cfg80211 data */
535 		if (cbss) {
536 			cbss->channel = sdata->deflink.csa.chanreq.oper.chan;
537 			cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
538 		}
539 	}
540 
541 	ifibss->chandef = sdata->deflink.csa.chanreq.oper;
542 
543 	/* generate the beacon */
544 	return ieee80211_ibss_csa_beacon(sdata, NULL, changed);
545 }
546 
547 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
548 {
549 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
550 
551 	wiphy_work_cancel(sdata->local->hw.wiphy,
552 			  &ifibss->csa_connection_drop_work);
553 }
554 
555 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
556 	__acquires(RCU)
557 {
558 	struct ieee80211_sub_if_data *sdata = sta->sdata;
559 	u8 addr[ETH_ALEN];
560 
561 	memcpy(addr, sta->sta.addr, ETH_ALEN);
562 
563 	ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
564 
565 	sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
566 	sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
567 	/* authorize the station only if the network is not RSN protected. If
568 	 * not wait for the userspace to authorize it */
569 	if (!sta->sdata->u.ibss.control_port)
570 		sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
571 
572 	rate_control_rate_init(sta);
573 
574 	/* If it fails, maybe we raced another insertion? */
575 	if (sta_info_insert_rcu(sta))
576 		return sta_info_get(sdata, addr);
577 	return sta;
578 }
579 
580 static struct sta_info *
581 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
582 		       const u8 *addr, u32 supp_rates)
583 	__acquires(RCU)
584 {
585 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
586 	struct ieee80211_local *local = sdata->local;
587 	struct sta_info *sta;
588 	struct ieee80211_chanctx_conf *chanctx_conf;
589 	struct ieee80211_supported_band *sband;
590 	int band;
591 
592 	/*
593 	 * XXX: Consider removing the least recently used entry and
594 	 * 	allow new one to be added.
595 	 */
596 	if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
597 		net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
598 				    sdata->name, addr);
599 		rcu_read_lock();
600 		return NULL;
601 	}
602 
603 	if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
604 		rcu_read_lock();
605 		return NULL;
606 	}
607 
608 	if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
609 		rcu_read_lock();
610 		return NULL;
611 	}
612 
613 	rcu_read_lock();
614 	chanctx_conf = rcu_dereference(sdata->vif.bss_conf.chanctx_conf);
615 	if (WARN_ON_ONCE(!chanctx_conf))
616 		return NULL;
617 	band = chanctx_conf->def.chan->band;
618 	rcu_read_unlock();
619 
620 	sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
621 	if (!sta) {
622 		rcu_read_lock();
623 		return NULL;
624 	}
625 
626 	/* make sure mandatory rates are always added */
627 	sband = local->hw.wiphy->bands[band];
628 	sta->sta.deflink.supp_rates[band] = supp_rates |
629 			ieee80211_mandatory_rates(sband);
630 
631 	return ieee80211_ibss_finish_sta(sta);
632 }
633 
634 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
635 {
636 	struct ieee80211_local *local = sdata->local;
637 	int active = 0;
638 	struct sta_info *sta;
639 
640 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
641 
642 	rcu_read_lock();
643 
644 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
645 		unsigned long last_active = ieee80211_sta_last_active(sta);
646 
647 		if (sta->sdata == sdata &&
648 		    time_is_after_jiffies(last_active +
649 					  IEEE80211_IBSS_MERGE_INTERVAL)) {
650 			active++;
651 			break;
652 		}
653 	}
654 
655 	rcu_read_unlock();
656 
657 	return active;
658 }
659 
660 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
661 {
662 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
663 	struct ieee80211_local *local = sdata->local;
664 	struct cfg80211_bss *cbss;
665 	struct beacon_data *presp;
666 	struct sta_info *sta;
667 
668 	lockdep_assert_wiphy(local->hw.wiphy);
669 
670 	if (!is_zero_ether_addr(ifibss->bssid)) {
671 		cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
672 					ifibss->bssid, ifibss->ssid,
673 					ifibss->ssid_len,
674 					IEEE80211_BSS_TYPE_IBSS,
675 					IEEE80211_PRIVACY(ifibss->privacy));
676 
677 		if (cbss) {
678 			cfg80211_unlink_bss(local->hw.wiphy, cbss);
679 			cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
680 		}
681 	}
682 
683 	ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
684 
685 	sta_info_flush(sdata, -1);
686 
687 	spin_lock_bh(&ifibss->incomplete_lock);
688 	while (!list_empty(&ifibss->incomplete_stations)) {
689 		sta = list_first_entry(&ifibss->incomplete_stations,
690 				       struct sta_info, list);
691 		list_del(&sta->list);
692 		spin_unlock_bh(&ifibss->incomplete_lock);
693 
694 		sta_info_free(local, sta);
695 		spin_lock_bh(&ifibss->incomplete_lock);
696 	}
697 	spin_unlock_bh(&ifibss->incomplete_lock);
698 
699 	netif_carrier_off(sdata->dev);
700 
701 	sdata->vif.cfg.ibss_joined = false;
702 	sdata->vif.cfg.ibss_creator = false;
703 	sdata->vif.bss_conf.enable_beacon = false;
704 	sdata->vif.cfg.ssid_len = 0;
705 
706 	/* remove beacon */
707 	presp = sdata_dereference(ifibss->presp, sdata);
708 	RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
709 	if (presp)
710 		kfree_rcu(presp, rcu_head);
711 
712 	clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
713 	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
714 						BSS_CHANGED_IBSS);
715 	drv_leave_ibss(local, sdata);
716 	ieee80211_link_release_channel(&sdata->deflink);
717 }
718 
719 static void ieee80211_csa_connection_drop_work(struct wiphy *wiphy,
720 					       struct wiphy_work *work)
721 {
722 	struct ieee80211_sub_if_data *sdata =
723 		container_of(work, struct ieee80211_sub_if_data,
724 			     u.ibss.csa_connection_drop_work);
725 
726 	ieee80211_ibss_disconnect(sdata);
727 	synchronize_rcu();
728 	skb_queue_purge(&sdata->skb_queue);
729 
730 	/* trigger a scan to find another IBSS network to join */
731 	wiphy_work_queue(sdata->local->hw.wiphy, &sdata->work);
732 }
733 
734 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
735 {
736 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
737 	int err;
738 
739 	/* if the current channel is a DFS channel, mark the channel as
740 	 * unavailable.
741 	 */
742 	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
743 					    &ifibss->chandef,
744 					    NL80211_IFTYPE_ADHOC);
745 	if (err > 0)
746 		cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
747 				     GFP_ATOMIC);
748 }
749 
750 static bool
751 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
752 				  struct ieee802_11_elems *elems,
753 				  bool beacon)
754 {
755 	struct cfg80211_csa_settings params;
756 	struct ieee80211_csa_ie csa_ie;
757 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
758 	enum nl80211_channel_type ch_type;
759 	int err;
760 	struct ieee80211_conn_settings conn = {
761 		.mode = IEEE80211_CONN_MODE_HT,
762 		.bw_limit = IEEE80211_CONN_BW_LIMIT_40,
763 	};
764 	u32 vht_cap_info = 0;
765 
766 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
767 
768 	switch (ifibss->chandef.width) {
769 	case NL80211_CHAN_WIDTH_5:
770 	case NL80211_CHAN_WIDTH_10:
771 	case NL80211_CHAN_WIDTH_20_NOHT:
772 		conn.mode = IEEE80211_CONN_MODE_LEGACY;
773 		fallthrough;
774 	case NL80211_CHAN_WIDTH_20:
775 		conn.bw_limit = IEEE80211_CONN_BW_LIMIT_20;
776 		break;
777 	default:
778 		break;
779 	}
780 
781 	if (elems->vht_cap_elem)
782 		vht_cap_info = le32_to_cpu(elems->vht_cap_elem->vht_cap_info);
783 
784 	memset(&params, 0, sizeof(params));
785 	err = ieee80211_parse_ch_switch_ie(sdata, elems,
786 					   ifibss->chandef.chan->band,
787 					   vht_cap_info, &conn,
788 					   ifibss->bssid, false,
789 					   &csa_ie);
790 	/* can't switch to destination channel, fail */
791 	if (err < 0)
792 		goto disconnect;
793 
794 	/* did not contain a CSA */
795 	if (err)
796 		return false;
797 
798 	/* channel switch is not supported, disconnect */
799 	if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
800 		goto disconnect;
801 
802 	params.count = csa_ie.count;
803 	params.chandef = csa_ie.chanreq.oper;
804 
805 	switch (ifibss->chandef.width) {
806 	case NL80211_CHAN_WIDTH_20_NOHT:
807 	case NL80211_CHAN_WIDTH_20:
808 	case NL80211_CHAN_WIDTH_40:
809 		/* keep our current HT mode (HT20/HT40+/HT40-), even if
810 		 * another mode  has been announced. The mode is not adopted
811 		 * within the beacon while doing CSA and we should therefore
812 		 * keep the mode which we announce.
813 		 */
814 		ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
815 		cfg80211_chandef_create(&params.chandef, params.chandef.chan,
816 					ch_type);
817 		break;
818 	case NL80211_CHAN_WIDTH_5:
819 	case NL80211_CHAN_WIDTH_10:
820 		if (params.chandef.width != ifibss->chandef.width) {
821 			sdata_info(sdata,
822 				   "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
823 				   ifibss->bssid,
824 				   params.chandef.chan->center_freq,
825 				   params.chandef.width,
826 				   params.chandef.center_freq1,
827 				   params.chandef.center_freq2);
828 			goto disconnect;
829 		}
830 		break;
831 	default:
832 		/* should not happen, conn_flags should prevent VHT modes. */
833 		WARN_ON(1);
834 		goto disconnect;
835 	}
836 
837 	if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef,
838 				     NL80211_IFTYPE_ADHOC)) {
839 		sdata_info(sdata,
840 			   "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
841 			   ifibss->bssid,
842 			   params.chandef.chan->center_freq,
843 			   params.chandef.width,
844 			   params.chandef.center_freq1,
845 			   params.chandef.center_freq2);
846 		goto disconnect;
847 	}
848 
849 	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
850 					    &params.chandef,
851 					    NL80211_IFTYPE_ADHOC);
852 	if (err < 0)
853 		goto disconnect;
854 	if (err > 0 && !ifibss->userspace_handles_dfs) {
855 		/* IBSS-DFS only allowed with a control program */
856 		goto disconnect;
857 	}
858 
859 	params.radar_required = err;
860 
861 	if (cfg80211_chandef_identical(&params.chandef,
862 				       &sdata->vif.bss_conf.chanreq.oper)) {
863 		ibss_dbg(sdata,
864 			 "received csa with an identical chandef, ignoring\n");
865 		return true;
866 	}
867 
868 	/* all checks done, now perform the channel switch. */
869 	ibss_dbg(sdata,
870 		 "received channel switch announcement to go to channel %d MHz\n",
871 		 params.chandef.chan->center_freq);
872 
873 	params.block_tx = !!csa_ie.mode;
874 
875 	if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
876 				     &params))
877 		goto disconnect;
878 
879 	ieee80211_ibss_csa_mark_radar(sdata);
880 
881 	return true;
882 disconnect:
883 	ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
884 	wiphy_work_queue(sdata->local->hw.wiphy,
885 			 &ifibss->csa_connection_drop_work);
886 
887 	ieee80211_ibss_csa_mark_radar(sdata);
888 
889 	return true;
890 }
891 
892 static void
893 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
894 				struct ieee80211_mgmt *mgmt, size_t len,
895 				struct ieee80211_rx_status *rx_status,
896 				struct ieee802_11_elems *elems)
897 {
898 	int required_len;
899 
900 	if (len < IEEE80211_MIN_ACTION_SIZE + 1)
901 		return;
902 
903 	/* CSA is the only action we handle for now */
904 	if (mgmt->u.action.u.measurement.action_code !=
905 	    WLAN_ACTION_SPCT_CHL_SWITCH)
906 		return;
907 
908 	required_len = IEEE80211_MIN_ACTION_SIZE +
909 		       sizeof(mgmt->u.action.u.chan_switch);
910 	if (len < required_len)
911 		return;
912 
913 	if (!sdata->vif.bss_conf.csa_active)
914 		ieee80211_ibss_process_chanswitch(sdata, elems, false);
915 }
916 
917 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
918 					  struct ieee80211_mgmt *mgmt,
919 					  size_t len)
920 {
921 	u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
922 
923 	if (len < IEEE80211_DEAUTH_FRAME_LEN)
924 		return;
925 
926 	ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
927 	ibss_dbg(sdata, "\tBSSID=%pM (reason: %d)\n", mgmt->bssid, reason);
928 	sta_info_destroy_addr(sdata, mgmt->sa);
929 }
930 
931 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
932 					struct ieee80211_mgmt *mgmt,
933 					size_t len)
934 {
935 	u16 auth_alg, auth_transaction;
936 
937 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
938 
939 	if (len < 24 + 6)
940 		return;
941 
942 	auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
943 	auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
944 
945 	ibss_dbg(sdata, "RX Auth SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
946 	ibss_dbg(sdata, "\tBSSID=%pM (auth_transaction=%d)\n",
947 		 mgmt->bssid, auth_transaction);
948 
949 	if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
950 		return;
951 
952 	/*
953 	 * IEEE 802.11 standard does not require authentication in IBSS
954 	 * networks and most implementations do not seem to use it.
955 	 * However, try to reply to authentication attempts if someone
956 	 * has actually implemented this.
957 	 */
958 	ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
959 			    mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
960 }
961 
962 static void ieee80211_update_sta_info(struct ieee80211_sub_if_data *sdata,
963 				      struct ieee80211_mgmt *mgmt, size_t len,
964 				      struct ieee80211_rx_status *rx_status,
965 				      struct ieee802_11_elems *elems,
966 				      struct ieee80211_channel *channel)
967 {
968 	struct sta_info *sta;
969 	enum nl80211_band band = rx_status->band;
970 	struct ieee80211_local *local = sdata->local;
971 	struct ieee80211_supported_band *sband;
972 	bool rates_updated = false;
973 	u32 supp_rates = 0;
974 
975 	if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
976 		return;
977 
978 	if (!ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid))
979 		return;
980 
981 	sband = local->hw.wiphy->bands[band];
982 	if (WARN_ON(!sband))
983 		return;
984 
985 	rcu_read_lock();
986 	sta = sta_info_get(sdata, mgmt->sa);
987 
988 	if (elems->supp_rates) {
989 		supp_rates = ieee80211_sta_get_rates(sdata, elems,
990 						     band, NULL);
991 		if (sta) {
992 			u32 prev_rates;
993 
994 			prev_rates = sta->sta.deflink.supp_rates[band];
995 
996 			sta->sta.deflink.supp_rates[band] = supp_rates |
997 				ieee80211_mandatory_rates(sband);
998 			if (sta->sta.deflink.supp_rates[band] != prev_rates) {
999 				ibss_dbg(sdata,
1000 					 "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1001 					 sta->sta.addr, prev_rates,
1002 					 sta->sta.deflink.supp_rates[band]);
1003 				rates_updated = true;
1004 			}
1005 		} else {
1006 			rcu_read_unlock();
1007 			sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1008 						     mgmt->sa, supp_rates);
1009 		}
1010 	}
1011 
1012 	if (sta && !sta->sta.wme &&
1013 	    (elems->wmm_info || elems->s1g_capab) &&
1014 	    local->hw.queues >= IEEE80211_NUM_ACS) {
1015 		sta->sta.wme = true;
1016 		ieee80211_check_fast_xmit(sta);
1017 	}
1018 
1019 	if (sta && elems->ht_operation && elems->ht_cap_elem &&
1020 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1021 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1022 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1023 		/* we both use HT */
1024 		struct ieee80211_ht_cap htcap_ie;
1025 		struct cfg80211_chan_def chandef;
1026 		enum ieee80211_sta_rx_bandwidth bw = sta->sta.deflink.bandwidth;
1027 
1028 		cfg80211_chandef_create(&chandef, channel, NL80211_CHAN_NO_HT);
1029 		ieee80211_chandef_ht_oper(elems->ht_operation, &chandef);
1030 
1031 		memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1032 		rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
1033 								   &htcap_ie,
1034 								   &sta->deflink);
1035 
1036 		if (elems->vht_operation && elems->vht_cap_elem &&
1037 		    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20 &&
1038 		    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_40) {
1039 			/* we both use VHT */
1040 			struct ieee80211_vht_cap cap_ie;
1041 			struct ieee80211_sta_vht_cap cap = sta->sta.deflink.vht_cap;
1042 			u32 vht_cap_info =
1043 				le32_to_cpu(elems->vht_cap_elem->vht_cap_info);
1044 
1045 			ieee80211_chandef_vht_oper(&local->hw, vht_cap_info,
1046 						   elems->vht_operation,
1047 						   elems->ht_operation,
1048 						   &chandef);
1049 			memcpy(&cap_ie, elems->vht_cap_elem, sizeof(cap_ie));
1050 			ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
1051 							    &cap_ie, NULL,
1052 							    &sta->deflink);
1053 			if (memcmp(&cap, &sta->sta.deflink.vht_cap, sizeof(cap)))
1054 				rates_updated |= true;
1055 		}
1056 
1057 		if (bw != sta->sta.deflink.bandwidth)
1058 			rates_updated |= true;
1059 
1060 		if (!cfg80211_chandef_compatible(&sdata->u.ibss.chandef,
1061 						 &chandef))
1062 			WARN_ON_ONCE(1);
1063 	}
1064 
1065 	if (sta && rates_updated) {
1066 		u32 changed = IEEE80211_RC_SUPP_RATES_CHANGED;
1067 		u8 rx_nss = sta->sta.deflink.rx_nss;
1068 
1069 		/* Force rx_nss recalculation */
1070 		sta->sta.deflink.rx_nss = 0;
1071 		rate_control_rate_init(sta);
1072 		if (sta->sta.deflink.rx_nss != rx_nss)
1073 			changed |= IEEE80211_RC_NSS_CHANGED;
1074 
1075 		drv_sta_rc_update(local, sdata, &sta->sta, changed);
1076 	}
1077 
1078 	rcu_read_unlock();
1079 }
1080 
1081 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
1082 				  struct ieee80211_mgmt *mgmt, size_t len,
1083 				  struct ieee80211_rx_status *rx_status,
1084 				  struct ieee802_11_elems *elems)
1085 {
1086 	struct ieee80211_local *local = sdata->local;
1087 	struct cfg80211_bss *cbss;
1088 	struct ieee80211_bss *bss;
1089 	struct ieee80211_channel *channel;
1090 	u64 beacon_timestamp, rx_timestamp;
1091 	u32 supp_rates = 0;
1092 	enum nl80211_band band = rx_status->band;
1093 
1094 	channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
1095 	if (!channel)
1096 		return;
1097 
1098 	ieee80211_update_sta_info(sdata, mgmt, len, rx_status, elems, channel);
1099 
1100 	bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, channel);
1101 	if (!bss)
1102 		return;
1103 
1104 	cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1105 
1106 	/* same for beacon and probe response */
1107 	beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1108 
1109 	/* check if we need to merge IBSS */
1110 
1111 	/* not an IBSS */
1112 	if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1113 		goto put_bss;
1114 
1115 	/* different channel */
1116 	if (sdata->u.ibss.fixed_channel &&
1117 	    sdata->u.ibss.chandef.chan != cbss->channel)
1118 		goto put_bss;
1119 
1120 	/* different SSID */
1121 	if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1122 	    memcmp(elems->ssid, sdata->u.ibss.ssid,
1123 				sdata->u.ibss.ssid_len))
1124 		goto put_bss;
1125 
1126 	/* process channel switch */
1127 	if (sdata->vif.bss_conf.csa_active ||
1128 	    ieee80211_ibss_process_chanswitch(sdata, elems, true))
1129 		goto put_bss;
1130 
1131 	/* same BSSID */
1132 	if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1133 		goto put_bss;
1134 
1135 	/* we use a fixed BSSID */
1136 	if (sdata->u.ibss.fixed_bssid)
1137 		goto put_bss;
1138 
1139 	if (ieee80211_have_rx_timestamp(rx_status)) {
1140 		/* time when timestamp field was received */
1141 		rx_timestamp =
1142 			ieee80211_calculate_rx_timestamp(local, rx_status,
1143 							 len + FCS_LEN, 24);
1144 	} else {
1145 		/*
1146 		 * second best option: get current TSF
1147 		 * (will return -1 if not supported)
1148 		 */
1149 		rx_timestamp = drv_get_tsf(local, sdata);
1150 	}
1151 
1152 	ibss_dbg(sdata, "RX beacon SA=%pM BSSID=%pM TSF=0x%llx\n",
1153 		 mgmt->sa, mgmt->bssid,
1154 		 (unsigned long long)rx_timestamp);
1155 	ibss_dbg(sdata, "\tBCN=0x%llx diff=%lld @%lu\n",
1156 		 (unsigned long long)beacon_timestamp,
1157 		 (unsigned long long)(rx_timestamp - beacon_timestamp),
1158 		 jiffies);
1159 
1160 	if (beacon_timestamp > rx_timestamp) {
1161 		ibss_dbg(sdata,
1162 			 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1163 			 mgmt->bssid);
1164 		ieee80211_sta_join_ibss(sdata, bss);
1165 		supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1166 		ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1167 				       supp_rates);
1168 		rcu_read_unlock();
1169 	}
1170 
1171  put_bss:
1172 	ieee80211_rx_bss_put(local, bss);
1173 }
1174 
1175 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1176 			      const u8 *bssid, const u8 *addr,
1177 			      u32 supp_rates)
1178 {
1179 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1180 	struct ieee80211_local *local = sdata->local;
1181 	struct sta_info *sta;
1182 	struct ieee80211_chanctx_conf *chanctx_conf;
1183 	struct ieee80211_supported_band *sband;
1184 	int band;
1185 
1186 	/*
1187 	 * XXX: Consider removing the least recently used entry and
1188 	 * 	allow new one to be added.
1189 	 */
1190 	if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1191 		net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1192 				    sdata->name, addr);
1193 		return;
1194 	}
1195 
1196 	if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1197 		return;
1198 
1199 	if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1200 		return;
1201 
1202 	rcu_read_lock();
1203 	chanctx_conf = rcu_dereference(sdata->vif.bss_conf.chanctx_conf);
1204 	if (WARN_ON_ONCE(!chanctx_conf)) {
1205 		rcu_read_unlock();
1206 		return;
1207 	}
1208 	band = chanctx_conf->def.chan->band;
1209 	rcu_read_unlock();
1210 
1211 	sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1212 	if (!sta)
1213 		return;
1214 
1215 	/* make sure mandatory rates are always added */
1216 	sband = local->hw.wiphy->bands[band];
1217 	sta->sta.deflink.supp_rates[band] = supp_rates |
1218 			ieee80211_mandatory_rates(sband);
1219 
1220 	spin_lock(&ifibss->incomplete_lock);
1221 	list_add(&sta->list, &ifibss->incomplete_stations);
1222 	spin_unlock(&ifibss->incomplete_lock);
1223 	wiphy_work_queue(local->hw.wiphy, &sdata->work);
1224 }
1225 
1226 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1227 {
1228 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1229 	struct ieee80211_local *local = sdata->local;
1230 	struct sta_info *sta, *tmp;
1231 	unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1232 	unsigned long exp_rsn = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1233 
1234 	lockdep_assert_wiphy(local->hw.wiphy);
1235 
1236 	list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1237 		unsigned long last_active = ieee80211_sta_last_active(sta);
1238 
1239 		if (sdata != sta->sdata)
1240 			continue;
1241 
1242 		if (time_is_before_jiffies(last_active + exp_time) ||
1243 		    (time_is_before_jiffies(last_active + exp_rsn) &&
1244 		     sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1245 			u8 frame_buf[IEEE80211_DEAUTH_FRAME_LEN];
1246 
1247 			sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1248 				sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1249 				"not authorized " : "", sta->sta.addr);
1250 
1251 			ieee80211_send_deauth_disassoc(sdata, sta->sta.addr,
1252 						       ifibss->bssid,
1253 						       IEEE80211_STYPE_DEAUTH,
1254 						       WLAN_REASON_DEAUTH_LEAVING,
1255 						       true, frame_buf);
1256 			WARN_ON(__sta_info_destroy(sta));
1257 		}
1258 	}
1259 }
1260 
1261 /*
1262  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1263  */
1264 
1265 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1266 {
1267 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1268 
1269 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
1270 
1271 	mod_timer(&ifibss->timer,
1272 		  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1273 
1274 	ieee80211_ibss_sta_expire(sdata);
1275 
1276 	if (time_before(jiffies, ifibss->last_scan_completed +
1277 		       IEEE80211_IBSS_MERGE_INTERVAL))
1278 		return;
1279 
1280 	if (ieee80211_sta_active_ibss(sdata))
1281 		return;
1282 
1283 	if (ifibss->fixed_channel)
1284 		return;
1285 
1286 	sdata_info(sdata,
1287 		   "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1288 
1289 	ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1290 				    NULL, 0);
1291 }
1292 
1293 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1294 {
1295 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1296 	u8 bssid[ETH_ALEN];
1297 	u16 capability;
1298 	int i;
1299 
1300 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
1301 
1302 	if (ifibss->fixed_bssid) {
1303 		memcpy(bssid, ifibss->bssid, ETH_ALEN);
1304 	} else {
1305 		/* Generate random, not broadcast, locally administered BSSID. Mix in
1306 		 * own MAC address to make sure that devices that do not have proper
1307 		 * random number generator get different BSSID. */
1308 		get_random_bytes(bssid, ETH_ALEN);
1309 		for (i = 0; i < ETH_ALEN; i++)
1310 			bssid[i] ^= sdata->vif.addr[i];
1311 		bssid[0] &= ~0x01;
1312 		bssid[0] |= 0x02;
1313 	}
1314 
1315 	sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1316 
1317 	capability = WLAN_CAPABILITY_IBSS;
1318 
1319 	if (ifibss->privacy)
1320 		capability |= WLAN_CAPABILITY_PRIVACY;
1321 
1322 	__ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1323 				  &ifibss->chandef, ifibss->basic_rates,
1324 				  capability, 0, true);
1325 }
1326 
1327 static unsigned int ibss_setup_channels(struct wiphy *wiphy,
1328 					struct ieee80211_channel **channels,
1329 					unsigned int channels_max,
1330 					u32 center_freq, u32 width)
1331 {
1332 	struct ieee80211_channel *chan = NULL;
1333 	unsigned int n_chan = 0;
1334 	u32 start_freq, end_freq, freq;
1335 
1336 	if (width <= 20) {
1337 		start_freq = center_freq;
1338 		end_freq = center_freq;
1339 	} else {
1340 		start_freq = center_freq - width / 2 + 10;
1341 		end_freq = center_freq + width / 2 - 10;
1342 	}
1343 
1344 	for (freq = start_freq; freq <= end_freq; freq += 20) {
1345 		chan = ieee80211_get_channel(wiphy, freq);
1346 		if (!chan)
1347 			continue;
1348 		if (n_chan >= channels_max)
1349 			return n_chan;
1350 
1351 		channels[n_chan] = chan;
1352 		n_chan++;
1353 	}
1354 
1355 	return n_chan;
1356 }
1357 
1358 static unsigned int
1359 ieee80211_ibss_setup_scan_channels(struct wiphy *wiphy,
1360 				   const struct cfg80211_chan_def *chandef,
1361 				   struct ieee80211_channel **channels,
1362 				   unsigned int channels_max)
1363 {
1364 	unsigned int n_chan = 0;
1365 	u32 width, cf1, cf2 = 0;
1366 
1367 	switch (chandef->width) {
1368 	case NL80211_CHAN_WIDTH_40:
1369 		width = 40;
1370 		break;
1371 	case NL80211_CHAN_WIDTH_80P80:
1372 		cf2 = chandef->center_freq2;
1373 		fallthrough;
1374 	case NL80211_CHAN_WIDTH_80:
1375 		width = 80;
1376 		break;
1377 	case NL80211_CHAN_WIDTH_160:
1378 		width = 160;
1379 		break;
1380 	default:
1381 		width = 20;
1382 		break;
1383 	}
1384 
1385 	cf1 = chandef->center_freq1;
1386 
1387 	n_chan = ibss_setup_channels(wiphy, channels, channels_max, cf1, width);
1388 
1389 	if (cf2)
1390 		n_chan += ibss_setup_channels(wiphy, &channels[n_chan],
1391 					      channels_max - n_chan, cf2,
1392 					      width);
1393 
1394 	return n_chan;
1395 }
1396 
1397 /*
1398  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1399  */
1400 
1401 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1402 {
1403 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1404 	struct ieee80211_local *local = sdata->local;
1405 	struct cfg80211_bss *cbss;
1406 	struct ieee80211_channel *chan = NULL;
1407 	const u8 *bssid = NULL;
1408 	int active_ibss;
1409 
1410 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
1411 
1412 	active_ibss = ieee80211_sta_active_ibss(sdata);
1413 	ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1414 
1415 	if (active_ibss)
1416 		return;
1417 
1418 	if (ifibss->fixed_bssid)
1419 		bssid = ifibss->bssid;
1420 	if (ifibss->fixed_channel)
1421 		chan = ifibss->chandef.chan;
1422 	if (!is_zero_ether_addr(ifibss->bssid))
1423 		bssid = ifibss->bssid;
1424 	cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1425 				ifibss->ssid, ifibss->ssid_len,
1426 				IEEE80211_BSS_TYPE_IBSS,
1427 				IEEE80211_PRIVACY(ifibss->privacy));
1428 
1429 	if (cbss) {
1430 		struct ieee80211_bss *bss;
1431 
1432 		bss = (void *)cbss->priv;
1433 		ibss_dbg(sdata,
1434 			 "sta_find_ibss: selected %pM current %pM\n",
1435 			 cbss->bssid, ifibss->bssid);
1436 		sdata_info(sdata,
1437 			   "Selected IBSS BSSID %pM based on configured SSID\n",
1438 			   cbss->bssid);
1439 
1440 		ieee80211_sta_join_ibss(sdata, bss);
1441 		ieee80211_rx_bss_put(local, bss);
1442 		return;
1443 	}
1444 
1445 	/* if a fixed bssid and a fixed freq have been provided create the IBSS
1446 	 * directly and do not waste time scanning
1447 	 */
1448 	if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1449 		sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1450 			   bssid);
1451 		ieee80211_sta_create_ibss(sdata);
1452 		return;
1453 	}
1454 
1455 
1456 	ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1457 
1458 	/* Selected IBSS not found in current scan results - try to scan */
1459 	if (time_after(jiffies, ifibss->last_scan_completed +
1460 					IEEE80211_SCAN_INTERVAL)) {
1461 		struct ieee80211_channel *channels[8];
1462 		unsigned int num;
1463 
1464 		sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1465 
1466 		if (ifibss->fixed_channel) {
1467 			num = ieee80211_ibss_setup_scan_channels(local->hw.wiphy,
1468 								 &ifibss->chandef,
1469 								 channels,
1470 								 ARRAY_SIZE(channels));
1471 			ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1472 						    ifibss->ssid_len, channels,
1473 						    num);
1474 		} else {
1475 			ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1476 						    ifibss->ssid_len, NULL, 0);
1477 		}
1478 	} else {
1479 		int interval = IEEE80211_SCAN_INTERVAL;
1480 
1481 		if (time_after(jiffies, ifibss->ibss_join_req +
1482 			       IEEE80211_IBSS_JOIN_TIMEOUT))
1483 			ieee80211_sta_create_ibss(sdata);
1484 
1485 		mod_timer(&ifibss->timer,
1486 			  round_jiffies(jiffies + interval));
1487 	}
1488 }
1489 
1490 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1491 					struct sk_buff *req)
1492 {
1493 	struct ieee80211_mgmt *mgmt = (void *)req->data;
1494 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1495 	struct ieee80211_local *local = sdata->local;
1496 	int tx_last_beacon, len = req->len;
1497 	struct sk_buff *skb;
1498 	struct beacon_data *presp;
1499 	u8 *pos, *end;
1500 
1501 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
1502 
1503 	presp = sdata_dereference(ifibss->presp, sdata);
1504 
1505 	if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1506 	    len < 24 + 2 || !presp)
1507 		return;
1508 
1509 	tx_last_beacon = drv_tx_last_beacon(local);
1510 
1511 	ibss_dbg(sdata, "RX ProbeReq SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
1512 	ibss_dbg(sdata, "\tBSSID=%pM (tx_last_beacon=%d)\n",
1513 		 mgmt->bssid, tx_last_beacon);
1514 
1515 	if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1516 		return;
1517 
1518 	if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1519 	    !is_broadcast_ether_addr(mgmt->bssid))
1520 		return;
1521 
1522 	end = ((u8 *) mgmt) + len;
1523 	pos = mgmt->u.probe_req.variable;
1524 	if (pos[0] != WLAN_EID_SSID ||
1525 	    pos + 2 + pos[1] > end) {
1526 		ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1527 			 mgmt->sa);
1528 		return;
1529 	}
1530 	if (pos[1] != 0 &&
1531 	    (pos[1] != ifibss->ssid_len ||
1532 	     memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1533 		/* Ignore ProbeReq for foreign SSID */
1534 		return;
1535 	}
1536 
1537 	/* Reply with ProbeResp */
1538 	skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1539 	if (!skb)
1540 		return;
1541 
1542 	skb_reserve(skb, local->tx_headroom);
1543 	skb_put_data(skb, presp->head, presp->head_len);
1544 
1545 	memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1546 	ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1547 	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1548 
1549 	/* avoid excessive retries for probe request to wildcard SSIDs */
1550 	if (pos[1] == 0)
1551 		IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1552 
1553 	ieee80211_tx_skb(sdata, skb);
1554 }
1555 
1556 static
1557 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1558 				    struct ieee80211_mgmt *mgmt, size_t len,
1559 				    struct ieee80211_rx_status *rx_status)
1560 {
1561 	size_t baselen;
1562 	struct ieee802_11_elems *elems;
1563 
1564 	BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1565 		     offsetof(typeof(mgmt->u.beacon), variable));
1566 
1567 	/*
1568 	 * either beacon or probe_resp but the variable field is at the
1569 	 * same offset
1570 	 */
1571 	baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1572 	if (baselen > len)
1573 		return;
1574 
1575 	elems = ieee802_11_parse_elems(mgmt->u.probe_resp.variable,
1576 				       len - baselen, false, NULL);
1577 
1578 	if (elems) {
1579 		ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, elems);
1580 		kfree(elems);
1581 	}
1582 }
1583 
1584 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1585 				   struct sk_buff *skb)
1586 {
1587 	struct ieee80211_rx_status *rx_status;
1588 	struct ieee80211_mgmt *mgmt;
1589 	u16 fc;
1590 	struct ieee802_11_elems *elems;
1591 	int ies_len;
1592 
1593 	rx_status = IEEE80211_SKB_RXCB(skb);
1594 	mgmt = (struct ieee80211_mgmt *) skb->data;
1595 	fc = le16_to_cpu(mgmt->frame_control);
1596 
1597 	if (!sdata->u.ibss.ssid_len)
1598 		return; /* not ready to merge yet */
1599 
1600 	switch (fc & IEEE80211_FCTL_STYPE) {
1601 	case IEEE80211_STYPE_PROBE_REQ:
1602 		ieee80211_rx_mgmt_probe_req(sdata, skb);
1603 		break;
1604 	case IEEE80211_STYPE_PROBE_RESP:
1605 	case IEEE80211_STYPE_BEACON:
1606 		ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1607 					       rx_status);
1608 		break;
1609 	case IEEE80211_STYPE_AUTH:
1610 		ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1611 		break;
1612 	case IEEE80211_STYPE_DEAUTH:
1613 		ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1614 		break;
1615 	case IEEE80211_STYPE_ACTION:
1616 		switch (mgmt->u.action.category) {
1617 		case WLAN_CATEGORY_SPECTRUM_MGMT:
1618 			ies_len = skb->len -
1619 				  offsetof(struct ieee80211_mgmt,
1620 					   u.action.u.chan_switch.variable);
1621 
1622 			if (ies_len < 0)
1623 				break;
1624 
1625 			elems = ieee802_11_parse_elems(
1626 				mgmt->u.action.u.chan_switch.variable,
1627 				ies_len, true, NULL);
1628 
1629 			if (elems && !elems->parse_error)
1630 				ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt,
1631 								skb->len,
1632 								rx_status,
1633 								elems);
1634 			kfree(elems);
1635 			break;
1636 		}
1637 	}
1638 }
1639 
1640 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1641 {
1642 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1643 	struct sta_info *sta;
1644 
1645 	/*
1646 	 * Work could be scheduled after scan or similar
1647 	 * when we aren't even joined (or trying) with a
1648 	 * network.
1649 	 */
1650 	if (!ifibss->ssid_len)
1651 		return;
1652 
1653 	spin_lock_bh(&ifibss->incomplete_lock);
1654 	while (!list_empty(&ifibss->incomplete_stations)) {
1655 		sta = list_first_entry(&ifibss->incomplete_stations,
1656 				       struct sta_info, list);
1657 		list_del(&sta->list);
1658 		spin_unlock_bh(&ifibss->incomplete_lock);
1659 
1660 		ieee80211_ibss_finish_sta(sta);
1661 		rcu_read_unlock();
1662 		spin_lock_bh(&ifibss->incomplete_lock);
1663 	}
1664 	spin_unlock_bh(&ifibss->incomplete_lock);
1665 
1666 	switch (ifibss->state) {
1667 	case IEEE80211_IBSS_MLME_SEARCH:
1668 		ieee80211_sta_find_ibss(sdata);
1669 		break;
1670 	case IEEE80211_IBSS_MLME_JOINED:
1671 		ieee80211_sta_merge_ibss(sdata);
1672 		break;
1673 	default:
1674 		WARN_ON(1);
1675 		break;
1676 	}
1677 }
1678 
1679 static void ieee80211_ibss_timer(struct timer_list *t)
1680 {
1681 	struct ieee80211_sub_if_data *sdata =
1682 		from_timer(sdata, t, u.ibss.timer);
1683 
1684 	wiphy_work_queue(sdata->local->hw.wiphy, &sdata->work);
1685 }
1686 
1687 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1688 {
1689 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1690 
1691 	timer_setup(&ifibss->timer, ieee80211_ibss_timer, 0);
1692 	INIT_LIST_HEAD(&ifibss->incomplete_stations);
1693 	spin_lock_init(&ifibss->incomplete_lock);
1694 	wiphy_work_init(&ifibss->csa_connection_drop_work,
1695 			ieee80211_csa_connection_drop_work);
1696 }
1697 
1698 /* scan finished notification */
1699 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1700 {
1701 	struct ieee80211_sub_if_data *sdata;
1702 
1703 	lockdep_assert_wiphy(local->hw.wiphy);
1704 
1705 	list_for_each_entry(sdata, &local->interfaces, list) {
1706 		if (!ieee80211_sdata_running(sdata))
1707 			continue;
1708 		if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1709 			continue;
1710 		sdata->u.ibss.last_scan_completed = jiffies;
1711 	}
1712 }
1713 
1714 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1715 			struct cfg80211_ibss_params *params)
1716 {
1717 	u64 changed = 0;
1718 	u32 rate_flags;
1719 	struct ieee80211_supported_band *sband;
1720 	enum ieee80211_chanctx_mode chanmode;
1721 	struct ieee80211_local *local = sdata->local;
1722 	int radar_detect_width = 0;
1723 	int i;
1724 	int ret;
1725 
1726 	lockdep_assert_wiphy(local->hw.wiphy);
1727 
1728 	if (params->chandef.chan->freq_offset) {
1729 		/* this may work, but is untested */
1730 		return -EOPNOTSUPP;
1731 	}
1732 
1733 	ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1734 					    &params->chandef,
1735 					    sdata->wdev.iftype);
1736 	if (ret < 0)
1737 		return ret;
1738 
1739 	if (ret > 0) {
1740 		if (!params->userspace_handles_dfs)
1741 			return -EINVAL;
1742 		radar_detect_width = BIT(params->chandef.width);
1743 	}
1744 
1745 	chanmode = (params->channel_fixed && !ret) ?
1746 		IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE;
1747 
1748 	ret = ieee80211_check_combinations(sdata, &params->chandef, chanmode,
1749 					   radar_detect_width, -1);
1750 	if (ret < 0)
1751 		return ret;
1752 
1753 	if (params->bssid) {
1754 		memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1755 		sdata->u.ibss.fixed_bssid = true;
1756 	} else
1757 		sdata->u.ibss.fixed_bssid = false;
1758 
1759 	sdata->u.ibss.privacy = params->privacy;
1760 	sdata->u.ibss.control_port = params->control_port;
1761 	sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1762 	sdata->u.ibss.basic_rates = params->basic_rates;
1763 	sdata->u.ibss.last_scan_completed = jiffies;
1764 
1765 	/* fix basic_rates if channel does not support these rates */
1766 	rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1767 	sband = local->hw.wiphy->bands[params->chandef.chan->band];
1768 	for (i = 0; i < sband->n_bitrates; i++) {
1769 		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1770 			sdata->u.ibss.basic_rates &= ~BIT(i);
1771 	}
1772 	memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1773 	       sizeof(params->mcast_rate));
1774 
1775 	sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1776 
1777 	sdata->u.ibss.chandef = params->chandef;
1778 	sdata->u.ibss.fixed_channel = params->channel_fixed;
1779 
1780 	if (params->ie) {
1781 		sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1782 					   GFP_KERNEL);
1783 		if (sdata->u.ibss.ie)
1784 			sdata->u.ibss.ie_len = params->ie_len;
1785 	}
1786 
1787 	sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1788 	sdata->u.ibss.ibss_join_req = jiffies;
1789 
1790 	memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1791 	sdata->u.ibss.ssid_len = params->ssid_len;
1792 
1793 	memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1794 	       sizeof(sdata->u.ibss.ht_capa));
1795 	memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1796 	       sizeof(sdata->u.ibss.ht_capa_mask));
1797 
1798 	/*
1799 	 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1800 	 * reserved, but an HT STA shall protect HT transmissions as though
1801 	 * the HT Protection field were set to non-HT mixed mode.
1802 	 *
1803 	 * In an IBSS, the RIFS Mode field of the HT Operation element is
1804 	 * also reserved, but an HT STA shall operate as though this field
1805 	 * were set to 1.
1806 	 */
1807 
1808 	sdata->vif.bss_conf.ht_operation_mode |=
1809 		  IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1810 		| IEEE80211_HT_PARAM_RIFS_MODE;
1811 
1812 	changed |= BSS_CHANGED_HT | BSS_CHANGED_MCAST_RATE;
1813 	ieee80211_link_info_change_notify(sdata, &sdata->deflink, changed);
1814 
1815 	sdata->deflink.smps_mode = IEEE80211_SMPS_OFF;
1816 	sdata->deflink.needed_rx_chains = local->rx_chains;
1817 	sdata->control_port_over_nl80211 = params->control_port_over_nl80211;
1818 
1819 	wiphy_work_queue(local->hw.wiphy, &sdata->work);
1820 
1821 	return 0;
1822 }
1823 
1824 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1825 {
1826 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1827 
1828 	ieee80211_ibss_disconnect(sdata);
1829 	ifibss->ssid_len = 0;
1830 	eth_zero_addr(ifibss->bssid);
1831 
1832 	/* remove beacon */
1833 	kfree(sdata->u.ibss.ie);
1834 	sdata->u.ibss.ie = NULL;
1835 	sdata->u.ibss.ie_len = 0;
1836 
1837 	/* on the next join, re-program HT parameters */
1838 	memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1839 	memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1840 
1841 	synchronize_rcu();
1842 
1843 	skb_queue_purge(&sdata->skb_queue);
1844 
1845 	del_timer_sync(&sdata->u.ibss.timer);
1846 
1847 	return 0;
1848 }
1849