xref: /linux/net/mac80211/ibss.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
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->deflink);
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->deflink);
1072 		if (sta->sta.deflink.rx_nss != rx_nss)
1073 			changed |= IEEE80211_RC_NSS_CHANGED;
1074 
1075 		drv_link_sta_rc_update(local, sdata, &sta->sta.deflink,
1076 				       changed);
1077 	}
1078 
1079 	rcu_read_unlock();
1080 }
1081 
1082 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
1083 				  struct ieee80211_mgmt *mgmt, size_t len,
1084 				  struct ieee80211_rx_status *rx_status,
1085 				  struct ieee802_11_elems *elems)
1086 {
1087 	struct ieee80211_local *local = sdata->local;
1088 	struct cfg80211_bss *cbss;
1089 	struct ieee80211_bss *bss;
1090 	struct ieee80211_channel *channel;
1091 	u64 beacon_timestamp, rx_timestamp;
1092 	u32 supp_rates = 0;
1093 	enum nl80211_band band = rx_status->band;
1094 
1095 	channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
1096 	if (!channel)
1097 		return;
1098 
1099 	ieee80211_update_sta_info(sdata, mgmt, len, rx_status, elems, channel);
1100 
1101 	bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, channel);
1102 	if (!bss)
1103 		return;
1104 
1105 	cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1106 
1107 	/* same for beacon and probe response */
1108 	beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1109 
1110 	/* check if we need to merge IBSS */
1111 
1112 	/* not an IBSS */
1113 	if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1114 		goto put_bss;
1115 
1116 	/* different channel */
1117 	if (sdata->u.ibss.fixed_channel &&
1118 	    sdata->u.ibss.chandef.chan != cbss->channel)
1119 		goto put_bss;
1120 
1121 	/* different SSID */
1122 	if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1123 	    memcmp(elems->ssid, sdata->u.ibss.ssid,
1124 				sdata->u.ibss.ssid_len))
1125 		goto put_bss;
1126 
1127 	/* process channel switch */
1128 	if (sdata->vif.bss_conf.csa_active ||
1129 	    ieee80211_ibss_process_chanswitch(sdata, elems, true))
1130 		goto put_bss;
1131 
1132 	/* same BSSID */
1133 	if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1134 		goto put_bss;
1135 
1136 	/* we use a fixed BSSID */
1137 	if (sdata->u.ibss.fixed_bssid)
1138 		goto put_bss;
1139 
1140 	if (ieee80211_have_rx_timestamp(rx_status)) {
1141 		/* time when timestamp field was received */
1142 		rx_timestamp =
1143 			ieee80211_calculate_rx_timestamp(local, rx_status,
1144 							 len + FCS_LEN, 24);
1145 	} else {
1146 		/*
1147 		 * second best option: get current TSF
1148 		 * (will return -1 if not supported)
1149 		 */
1150 		rx_timestamp = drv_get_tsf(local, sdata);
1151 	}
1152 
1153 	ibss_dbg(sdata, "RX beacon SA=%pM BSSID=%pM TSF=0x%llx\n",
1154 		 mgmt->sa, mgmt->bssid,
1155 		 (unsigned long long)rx_timestamp);
1156 	ibss_dbg(sdata, "\tBCN=0x%llx diff=%lld @%lu\n",
1157 		 (unsigned long long)beacon_timestamp,
1158 		 (unsigned long long)(rx_timestamp - beacon_timestamp),
1159 		 jiffies);
1160 
1161 	if (beacon_timestamp > rx_timestamp) {
1162 		ibss_dbg(sdata,
1163 			 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1164 			 mgmt->bssid);
1165 		ieee80211_sta_join_ibss(sdata, bss);
1166 		supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1167 		ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1168 				       supp_rates);
1169 		rcu_read_unlock();
1170 	}
1171 
1172  put_bss:
1173 	ieee80211_rx_bss_put(local, bss);
1174 }
1175 
1176 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1177 			      const u8 *bssid, const u8 *addr,
1178 			      u32 supp_rates)
1179 {
1180 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1181 	struct ieee80211_local *local = sdata->local;
1182 	struct sta_info *sta;
1183 	struct ieee80211_chanctx_conf *chanctx_conf;
1184 	struct ieee80211_supported_band *sband;
1185 	int band;
1186 
1187 	/*
1188 	 * XXX: Consider removing the least recently used entry and
1189 	 * 	allow new one to be added.
1190 	 */
1191 	if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1192 		net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1193 				    sdata->name, addr);
1194 		return;
1195 	}
1196 
1197 	if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1198 		return;
1199 
1200 	if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1201 		return;
1202 
1203 	rcu_read_lock();
1204 	chanctx_conf = rcu_dereference(sdata->vif.bss_conf.chanctx_conf);
1205 	if (WARN_ON_ONCE(!chanctx_conf)) {
1206 		rcu_read_unlock();
1207 		return;
1208 	}
1209 	band = chanctx_conf->def.chan->band;
1210 	rcu_read_unlock();
1211 
1212 	sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1213 	if (!sta)
1214 		return;
1215 
1216 	/* make sure mandatory rates are always added */
1217 	sband = local->hw.wiphy->bands[band];
1218 	sta->sta.deflink.supp_rates[band] = supp_rates |
1219 			ieee80211_mandatory_rates(sband);
1220 
1221 	spin_lock(&ifibss->incomplete_lock);
1222 	list_add(&sta->list, &ifibss->incomplete_stations);
1223 	spin_unlock(&ifibss->incomplete_lock);
1224 	wiphy_work_queue(local->hw.wiphy, &sdata->work);
1225 }
1226 
1227 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1228 {
1229 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1230 	struct ieee80211_local *local = sdata->local;
1231 	struct sta_info *sta, *tmp;
1232 	unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1233 	unsigned long exp_rsn = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1234 
1235 	lockdep_assert_wiphy(local->hw.wiphy);
1236 
1237 	list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1238 		unsigned long last_active = ieee80211_sta_last_active(sta);
1239 
1240 		if (sdata != sta->sdata)
1241 			continue;
1242 
1243 		if (time_is_before_jiffies(last_active + exp_time) ||
1244 		    (time_is_before_jiffies(last_active + exp_rsn) &&
1245 		     sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1246 			u8 frame_buf[IEEE80211_DEAUTH_FRAME_LEN];
1247 
1248 			sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1249 				sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1250 				"not authorized " : "", sta->sta.addr);
1251 
1252 			ieee80211_send_deauth_disassoc(sdata, sta->sta.addr,
1253 						       ifibss->bssid,
1254 						       IEEE80211_STYPE_DEAUTH,
1255 						       WLAN_REASON_DEAUTH_LEAVING,
1256 						       true, frame_buf);
1257 			WARN_ON(__sta_info_destroy(sta));
1258 		}
1259 	}
1260 }
1261 
1262 /*
1263  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1264  */
1265 
1266 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1267 {
1268 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1269 
1270 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
1271 
1272 	mod_timer(&ifibss->timer,
1273 		  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1274 
1275 	ieee80211_ibss_sta_expire(sdata);
1276 
1277 	if (time_before(jiffies, ifibss->last_scan_completed +
1278 		       IEEE80211_IBSS_MERGE_INTERVAL))
1279 		return;
1280 
1281 	if (ieee80211_sta_active_ibss(sdata))
1282 		return;
1283 
1284 	if (ifibss->fixed_channel)
1285 		return;
1286 
1287 	sdata_info(sdata,
1288 		   "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1289 
1290 	ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1291 				    NULL, 0);
1292 }
1293 
1294 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1295 {
1296 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1297 	u8 bssid[ETH_ALEN];
1298 	u16 capability;
1299 	int i;
1300 
1301 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
1302 
1303 	if (ifibss->fixed_bssid) {
1304 		memcpy(bssid, ifibss->bssid, ETH_ALEN);
1305 	} else {
1306 		/* Generate random, not broadcast, locally administered BSSID. Mix in
1307 		 * own MAC address to make sure that devices that do not have proper
1308 		 * random number generator get different BSSID. */
1309 		get_random_bytes(bssid, ETH_ALEN);
1310 		for (i = 0; i < ETH_ALEN; i++)
1311 			bssid[i] ^= sdata->vif.addr[i];
1312 		bssid[0] &= ~0x01;
1313 		bssid[0] |= 0x02;
1314 	}
1315 
1316 	sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1317 
1318 	capability = WLAN_CAPABILITY_IBSS;
1319 
1320 	if (ifibss->privacy)
1321 		capability |= WLAN_CAPABILITY_PRIVACY;
1322 
1323 	__ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1324 				  &ifibss->chandef, ifibss->basic_rates,
1325 				  capability, 0, true);
1326 }
1327 
1328 static unsigned int ibss_setup_channels(struct wiphy *wiphy,
1329 					struct ieee80211_channel **channels,
1330 					unsigned int channels_max,
1331 					u32 center_freq, u32 width)
1332 {
1333 	struct ieee80211_channel *chan = NULL;
1334 	unsigned int n_chan = 0;
1335 	u32 start_freq, end_freq, freq;
1336 
1337 	if (width <= 20) {
1338 		start_freq = center_freq;
1339 		end_freq = center_freq;
1340 	} else {
1341 		start_freq = center_freq - width / 2 + 10;
1342 		end_freq = center_freq + width / 2 - 10;
1343 	}
1344 
1345 	for (freq = start_freq; freq <= end_freq; freq += 20) {
1346 		chan = ieee80211_get_channel(wiphy, freq);
1347 		if (!chan)
1348 			continue;
1349 		if (n_chan >= channels_max)
1350 			return n_chan;
1351 
1352 		channels[n_chan] = chan;
1353 		n_chan++;
1354 	}
1355 
1356 	return n_chan;
1357 }
1358 
1359 static unsigned int
1360 ieee80211_ibss_setup_scan_channels(struct wiphy *wiphy,
1361 				   const struct cfg80211_chan_def *chandef,
1362 				   struct ieee80211_channel **channels,
1363 				   unsigned int channels_max)
1364 {
1365 	unsigned int n_chan = 0;
1366 	u32 width, cf1, cf2 = 0;
1367 
1368 	switch (chandef->width) {
1369 	case NL80211_CHAN_WIDTH_40:
1370 		width = 40;
1371 		break;
1372 	case NL80211_CHAN_WIDTH_80P80:
1373 		cf2 = chandef->center_freq2;
1374 		fallthrough;
1375 	case NL80211_CHAN_WIDTH_80:
1376 		width = 80;
1377 		break;
1378 	case NL80211_CHAN_WIDTH_160:
1379 		width = 160;
1380 		break;
1381 	default:
1382 		width = 20;
1383 		break;
1384 	}
1385 
1386 	cf1 = chandef->center_freq1;
1387 
1388 	n_chan = ibss_setup_channels(wiphy, channels, channels_max, cf1, width);
1389 
1390 	if (cf2)
1391 		n_chan += ibss_setup_channels(wiphy, &channels[n_chan],
1392 					      channels_max - n_chan, cf2,
1393 					      width);
1394 
1395 	return n_chan;
1396 }
1397 
1398 /*
1399  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1400  */
1401 
1402 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1403 {
1404 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1405 	struct ieee80211_local *local = sdata->local;
1406 	struct cfg80211_bss *cbss;
1407 	struct ieee80211_channel *chan = NULL;
1408 	const u8 *bssid = NULL;
1409 	int active_ibss;
1410 
1411 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
1412 
1413 	active_ibss = ieee80211_sta_active_ibss(sdata);
1414 	ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1415 
1416 	if (active_ibss)
1417 		return;
1418 
1419 	if (ifibss->fixed_bssid)
1420 		bssid = ifibss->bssid;
1421 	if (ifibss->fixed_channel)
1422 		chan = ifibss->chandef.chan;
1423 	if (!is_zero_ether_addr(ifibss->bssid))
1424 		bssid = ifibss->bssid;
1425 	cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1426 				ifibss->ssid, ifibss->ssid_len,
1427 				IEEE80211_BSS_TYPE_IBSS,
1428 				IEEE80211_PRIVACY(ifibss->privacy));
1429 
1430 	if (cbss) {
1431 		struct ieee80211_bss *bss;
1432 
1433 		bss = (void *)cbss->priv;
1434 		ibss_dbg(sdata,
1435 			 "sta_find_ibss: selected %pM current %pM\n",
1436 			 cbss->bssid, ifibss->bssid);
1437 		sdata_info(sdata,
1438 			   "Selected IBSS BSSID %pM based on configured SSID\n",
1439 			   cbss->bssid);
1440 
1441 		ieee80211_sta_join_ibss(sdata, bss);
1442 		ieee80211_rx_bss_put(local, bss);
1443 		return;
1444 	}
1445 
1446 	/* if a fixed bssid and a fixed freq have been provided create the IBSS
1447 	 * directly and do not waste time scanning
1448 	 */
1449 	if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1450 		sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1451 			   bssid);
1452 		ieee80211_sta_create_ibss(sdata);
1453 		return;
1454 	}
1455 
1456 
1457 	ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1458 
1459 	/* Selected IBSS not found in current scan results - try to scan */
1460 	if (time_after(jiffies, ifibss->last_scan_completed +
1461 					IEEE80211_SCAN_INTERVAL)) {
1462 		struct ieee80211_channel *channels[8];
1463 		unsigned int num;
1464 
1465 		sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1466 
1467 		if (ifibss->fixed_channel) {
1468 			num = ieee80211_ibss_setup_scan_channels(local->hw.wiphy,
1469 								 &ifibss->chandef,
1470 								 channels,
1471 								 ARRAY_SIZE(channels));
1472 			ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1473 						    ifibss->ssid_len, channels,
1474 						    num);
1475 		} else {
1476 			ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1477 						    ifibss->ssid_len, NULL, 0);
1478 		}
1479 	} else {
1480 		int interval = IEEE80211_SCAN_INTERVAL;
1481 
1482 		if (time_after(jiffies, ifibss->ibss_join_req +
1483 			       IEEE80211_IBSS_JOIN_TIMEOUT))
1484 			ieee80211_sta_create_ibss(sdata);
1485 
1486 		mod_timer(&ifibss->timer,
1487 			  round_jiffies(jiffies + interval));
1488 	}
1489 }
1490 
1491 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1492 					struct sk_buff *req)
1493 {
1494 	struct ieee80211_mgmt *mgmt = (void *)req->data;
1495 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1496 	struct ieee80211_local *local = sdata->local;
1497 	int tx_last_beacon, len = req->len;
1498 	struct sk_buff *skb;
1499 	struct beacon_data *presp;
1500 	u8 *pos, *end;
1501 
1502 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
1503 
1504 	presp = sdata_dereference(ifibss->presp, sdata);
1505 
1506 	if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1507 	    len < 24 + 2 || !presp)
1508 		return;
1509 
1510 	tx_last_beacon = drv_tx_last_beacon(local);
1511 
1512 	ibss_dbg(sdata, "RX ProbeReq SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
1513 	ibss_dbg(sdata, "\tBSSID=%pM (tx_last_beacon=%d)\n",
1514 		 mgmt->bssid, tx_last_beacon);
1515 
1516 	if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1517 		return;
1518 
1519 	if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1520 	    !is_broadcast_ether_addr(mgmt->bssid))
1521 		return;
1522 
1523 	end = ((u8 *) mgmt) + len;
1524 	pos = mgmt->u.probe_req.variable;
1525 	if (pos[0] != WLAN_EID_SSID ||
1526 	    pos + 2 + pos[1] > end) {
1527 		ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1528 			 mgmt->sa);
1529 		return;
1530 	}
1531 	if (pos[1] != 0 &&
1532 	    (pos[1] != ifibss->ssid_len ||
1533 	     memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1534 		/* Ignore ProbeReq for foreign SSID */
1535 		return;
1536 	}
1537 
1538 	/* Reply with ProbeResp */
1539 	skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1540 	if (!skb)
1541 		return;
1542 
1543 	skb_reserve(skb, local->tx_headroom);
1544 	skb_put_data(skb, presp->head, presp->head_len);
1545 
1546 	memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1547 	ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1548 	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1549 
1550 	/* avoid excessive retries for probe request to wildcard SSIDs */
1551 	if (pos[1] == 0)
1552 		IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1553 
1554 	ieee80211_tx_skb(sdata, skb);
1555 }
1556 
1557 static
1558 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1559 				    struct ieee80211_mgmt *mgmt, size_t len,
1560 				    struct ieee80211_rx_status *rx_status)
1561 {
1562 	size_t baselen;
1563 	struct ieee802_11_elems *elems;
1564 
1565 	BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1566 		     offsetof(typeof(mgmt->u.beacon), variable));
1567 
1568 	/*
1569 	 * either beacon or probe_resp but the variable field is at the
1570 	 * same offset
1571 	 */
1572 	baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1573 	if (baselen > len)
1574 		return;
1575 
1576 	elems = ieee802_11_parse_elems(mgmt->u.probe_resp.variable,
1577 				       len - baselen, false, NULL);
1578 
1579 	if (elems) {
1580 		ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, elems);
1581 		kfree(elems);
1582 	}
1583 }
1584 
1585 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1586 				   struct sk_buff *skb)
1587 {
1588 	struct ieee80211_rx_status *rx_status;
1589 	struct ieee80211_mgmt *mgmt;
1590 	u16 fc;
1591 	struct ieee802_11_elems *elems;
1592 	int ies_len;
1593 
1594 	rx_status = IEEE80211_SKB_RXCB(skb);
1595 	mgmt = (struct ieee80211_mgmt *) skb->data;
1596 	fc = le16_to_cpu(mgmt->frame_control);
1597 
1598 	if (!sdata->u.ibss.ssid_len)
1599 		return; /* not ready to merge yet */
1600 
1601 	switch (fc & IEEE80211_FCTL_STYPE) {
1602 	case IEEE80211_STYPE_PROBE_REQ:
1603 		ieee80211_rx_mgmt_probe_req(sdata, skb);
1604 		break;
1605 	case IEEE80211_STYPE_PROBE_RESP:
1606 	case IEEE80211_STYPE_BEACON:
1607 		ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1608 					       rx_status);
1609 		break;
1610 	case IEEE80211_STYPE_AUTH:
1611 		ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1612 		break;
1613 	case IEEE80211_STYPE_DEAUTH:
1614 		ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1615 		break;
1616 	case IEEE80211_STYPE_ACTION:
1617 		switch (mgmt->u.action.category) {
1618 		case WLAN_CATEGORY_SPECTRUM_MGMT:
1619 			ies_len = skb->len -
1620 				  offsetof(struct ieee80211_mgmt,
1621 					   u.action.u.chan_switch.variable);
1622 
1623 			if (ies_len < 0)
1624 				break;
1625 
1626 			elems = ieee802_11_parse_elems(
1627 				mgmt->u.action.u.chan_switch.variable,
1628 				ies_len, true, NULL);
1629 
1630 			if (elems && !elems->parse_error)
1631 				ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt,
1632 								skb->len,
1633 								rx_status,
1634 								elems);
1635 			kfree(elems);
1636 			break;
1637 		}
1638 	}
1639 }
1640 
1641 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1642 {
1643 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1644 	struct sta_info *sta;
1645 
1646 	/*
1647 	 * Work could be scheduled after scan or similar
1648 	 * when we aren't even joined (or trying) with a
1649 	 * network.
1650 	 */
1651 	if (!ifibss->ssid_len)
1652 		return;
1653 
1654 	spin_lock_bh(&ifibss->incomplete_lock);
1655 	while (!list_empty(&ifibss->incomplete_stations)) {
1656 		sta = list_first_entry(&ifibss->incomplete_stations,
1657 				       struct sta_info, list);
1658 		list_del(&sta->list);
1659 		spin_unlock_bh(&ifibss->incomplete_lock);
1660 
1661 		ieee80211_ibss_finish_sta(sta);
1662 		rcu_read_unlock();
1663 		spin_lock_bh(&ifibss->incomplete_lock);
1664 	}
1665 	spin_unlock_bh(&ifibss->incomplete_lock);
1666 
1667 	switch (ifibss->state) {
1668 	case IEEE80211_IBSS_MLME_SEARCH:
1669 		ieee80211_sta_find_ibss(sdata);
1670 		break;
1671 	case IEEE80211_IBSS_MLME_JOINED:
1672 		ieee80211_sta_merge_ibss(sdata);
1673 		break;
1674 	default:
1675 		WARN_ON(1);
1676 		break;
1677 	}
1678 }
1679 
1680 static void ieee80211_ibss_timer(struct timer_list *t)
1681 {
1682 	struct ieee80211_sub_if_data *sdata =
1683 		from_timer(sdata, t, u.ibss.timer);
1684 
1685 	wiphy_work_queue(sdata->local->hw.wiphy, &sdata->work);
1686 }
1687 
1688 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1689 {
1690 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1691 
1692 	timer_setup(&ifibss->timer, ieee80211_ibss_timer, 0);
1693 	INIT_LIST_HEAD(&ifibss->incomplete_stations);
1694 	spin_lock_init(&ifibss->incomplete_lock);
1695 	wiphy_work_init(&ifibss->csa_connection_drop_work,
1696 			ieee80211_csa_connection_drop_work);
1697 }
1698 
1699 /* scan finished notification */
1700 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1701 {
1702 	struct ieee80211_sub_if_data *sdata;
1703 
1704 	lockdep_assert_wiphy(local->hw.wiphy);
1705 
1706 	list_for_each_entry(sdata, &local->interfaces, list) {
1707 		if (!ieee80211_sdata_running(sdata))
1708 			continue;
1709 		if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1710 			continue;
1711 		sdata->u.ibss.last_scan_completed = jiffies;
1712 	}
1713 }
1714 
1715 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1716 			struct cfg80211_ibss_params *params)
1717 {
1718 	u64 changed = 0;
1719 	u32 rate_flags;
1720 	struct ieee80211_supported_band *sband;
1721 	enum ieee80211_chanctx_mode chanmode;
1722 	struct ieee80211_local *local = sdata->local;
1723 	int radar_detect_width = 0;
1724 	int i;
1725 	int ret;
1726 
1727 	lockdep_assert_wiphy(local->hw.wiphy);
1728 
1729 	if (params->chandef.chan->freq_offset) {
1730 		/* this may work, but is untested */
1731 		return -EOPNOTSUPP;
1732 	}
1733 
1734 	ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1735 					    &params->chandef,
1736 					    sdata->wdev.iftype);
1737 	if (ret < 0)
1738 		return ret;
1739 
1740 	if (ret > 0) {
1741 		if (!params->userspace_handles_dfs)
1742 			return -EINVAL;
1743 		radar_detect_width = BIT(params->chandef.width);
1744 	}
1745 
1746 	chanmode = (params->channel_fixed && !ret) ?
1747 		IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE;
1748 
1749 	ret = ieee80211_check_combinations(sdata, &params->chandef, chanmode,
1750 					   radar_detect_width, -1);
1751 	if (ret < 0)
1752 		return ret;
1753 
1754 	if (params->bssid) {
1755 		memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1756 		sdata->u.ibss.fixed_bssid = true;
1757 	} else
1758 		sdata->u.ibss.fixed_bssid = false;
1759 
1760 	sdata->u.ibss.privacy = params->privacy;
1761 	sdata->u.ibss.control_port = params->control_port;
1762 	sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1763 	sdata->u.ibss.basic_rates = params->basic_rates;
1764 	sdata->u.ibss.last_scan_completed = jiffies;
1765 
1766 	/* fix basic_rates if channel does not support these rates */
1767 	rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1768 	sband = local->hw.wiphy->bands[params->chandef.chan->band];
1769 	for (i = 0; i < sband->n_bitrates; i++) {
1770 		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1771 			sdata->u.ibss.basic_rates &= ~BIT(i);
1772 	}
1773 	memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1774 	       sizeof(params->mcast_rate));
1775 
1776 	sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1777 
1778 	sdata->u.ibss.chandef = params->chandef;
1779 	sdata->u.ibss.fixed_channel = params->channel_fixed;
1780 
1781 	if (params->ie) {
1782 		sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1783 					   GFP_KERNEL);
1784 		if (sdata->u.ibss.ie)
1785 			sdata->u.ibss.ie_len = params->ie_len;
1786 	}
1787 
1788 	sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1789 	sdata->u.ibss.ibss_join_req = jiffies;
1790 
1791 	memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1792 	sdata->u.ibss.ssid_len = params->ssid_len;
1793 
1794 	memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1795 	       sizeof(sdata->u.ibss.ht_capa));
1796 	memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1797 	       sizeof(sdata->u.ibss.ht_capa_mask));
1798 
1799 	/*
1800 	 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1801 	 * reserved, but an HT STA shall protect HT transmissions as though
1802 	 * the HT Protection field were set to non-HT mixed mode.
1803 	 *
1804 	 * In an IBSS, the RIFS Mode field of the HT Operation element is
1805 	 * also reserved, but an HT STA shall operate as though this field
1806 	 * were set to 1.
1807 	 */
1808 
1809 	sdata->vif.bss_conf.ht_operation_mode |=
1810 		  IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1811 		| IEEE80211_HT_PARAM_RIFS_MODE;
1812 
1813 	changed |= BSS_CHANGED_HT | BSS_CHANGED_MCAST_RATE;
1814 	ieee80211_link_info_change_notify(sdata, &sdata->deflink, changed);
1815 
1816 	sdata->deflink.smps_mode = IEEE80211_SMPS_OFF;
1817 	sdata->deflink.needed_rx_chains = local->rx_chains;
1818 	sdata->control_port_over_nl80211 = params->control_port_over_nl80211;
1819 
1820 	wiphy_work_queue(local->hw.wiphy, &sdata->work);
1821 
1822 	return 0;
1823 }
1824 
1825 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1826 {
1827 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1828 
1829 	ieee80211_ibss_disconnect(sdata);
1830 	ifibss->ssid_len = 0;
1831 	eth_zero_addr(ifibss->bssid);
1832 
1833 	/* remove beacon */
1834 	kfree(sdata->u.ibss.ie);
1835 	sdata->u.ibss.ie = NULL;
1836 	sdata->u.ibss.ie_len = 0;
1837 
1838 	/* on the next join, re-program HT parameters */
1839 	memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1840 	memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1841 
1842 	synchronize_rcu();
1843 
1844 	skb_queue_purge(&sdata->skb_queue);
1845 
1846 	del_timer_sync(&sdata->u.ibss.timer);
1847 
1848 	return 0;
1849 }
1850