xref: /openbmc/linux/net/mac80211/ibss.c (revision 95298d63)
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) 2018-2020 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 	int shift;
55 
56 	/* Build IBSS probe response */
57 	frame_len = sizeof(struct ieee80211_hdr_3addr) +
58 		    12 /* struct ieee80211_mgmt.u.beacon */ +
59 		    2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
60 		    2 + 8 /* max Supported Rates */ +
61 		    3 /* max DS params */ +
62 		    4 /* IBSS params */ +
63 		    5 /* Channel Switch Announcement */ +
64 		    2 + (IEEE80211_MAX_SUPP_RATES - 8) +
65 		    2 + sizeof(struct ieee80211_ht_cap) +
66 		    2 + sizeof(struct ieee80211_ht_operation) +
67 		    2 + sizeof(struct ieee80211_vht_cap) +
68 		    2 + sizeof(struct ieee80211_vht_operation) +
69 		    ifibss->ie_len;
70 	presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
71 	if (!presp)
72 		return NULL;
73 
74 	presp->head = (void *)(presp + 1);
75 
76 	mgmt = (void *) presp->head;
77 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
78 					  IEEE80211_STYPE_PROBE_RESP);
79 	eth_broadcast_addr(mgmt->da);
80 	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
81 	memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
82 	mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
83 	mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
84 	mgmt->u.beacon.capab_info = cpu_to_le16(capability);
85 
86 	pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
87 
88 	*pos++ = WLAN_EID_SSID;
89 	*pos++ = ifibss->ssid_len;
90 	memcpy(pos, ifibss->ssid, ifibss->ssid_len);
91 	pos += ifibss->ssid_len;
92 
93 	sband = local->hw.wiphy->bands[chandef->chan->band];
94 	rate_flags = ieee80211_chandef_rate_flags(chandef);
95 	shift = ieee80211_chandef_get_shift(chandef);
96 	rates_n = 0;
97 	if (have_higher_than_11mbit)
98 		*have_higher_than_11mbit = false;
99 
100 	for (i = 0; i < sband->n_bitrates; i++) {
101 		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
102 			continue;
103 		if (sband->bitrates[i].bitrate > 110 &&
104 		    have_higher_than_11mbit)
105 			*have_higher_than_11mbit = true;
106 
107 		rates |= BIT(i);
108 		rates_n++;
109 	}
110 
111 	*pos++ = WLAN_EID_SUPP_RATES;
112 	*pos++ = min_t(int, 8, rates_n);
113 	for (ri = 0; ri < sband->n_bitrates; ri++) {
114 		int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
115 					5 * (1 << shift));
116 		u8 basic = 0;
117 		if (!(rates & BIT(ri)))
118 			continue;
119 
120 		if (basic_rates & BIT(ri))
121 			basic = 0x80;
122 		*pos++ = basic | (u8) rate;
123 		if (++rates_added == 8) {
124 			ri++; /* continue at next rate for EXT_SUPP_RATES */
125 			break;
126 		}
127 	}
128 
129 	if (sband->band == NL80211_BAND_2GHZ) {
130 		*pos++ = WLAN_EID_DS_PARAMS;
131 		*pos++ = 1;
132 		*pos++ = ieee80211_frequency_to_channel(
133 				chandef->chan->center_freq);
134 	}
135 
136 	*pos++ = WLAN_EID_IBSS_PARAMS;
137 	*pos++ = 2;
138 	/* FIX: set ATIM window based on scan results */
139 	*pos++ = 0;
140 	*pos++ = 0;
141 
142 	if (csa_settings) {
143 		*pos++ = WLAN_EID_CHANNEL_SWITCH;
144 		*pos++ = 3;
145 		*pos++ = csa_settings->block_tx ? 1 : 0;
146 		*pos++ = ieee80211_frequency_to_channel(
147 				csa_settings->chandef.chan->center_freq);
148 		presp->csa_counter_offsets[0] = (pos - presp->head);
149 		*pos++ = csa_settings->count;
150 		presp->csa_current_counter = csa_settings->count;
151 	}
152 
153 	/* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
154 	if (rates_n > 8) {
155 		*pos++ = WLAN_EID_EXT_SUPP_RATES;
156 		*pos++ = rates_n - 8;
157 		for (; ri < sband->n_bitrates; ri++) {
158 			int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
159 						5 * (1 << shift));
160 			u8 basic = 0;
161 			if (!(rates & BIT(ri)))
162 				continue;
163 
164 			if (basic_rates & BIT(ri))
165 				basic = 0x80;
166 			*pos++ = basic | (u8) rate;
167 		}
168 	}
169 
170 	if (ifibss->ie_len) {
171 		memcpy(pos, ifibss->ie, ifibss->ie_len);
172 		pos += ifibss->ie_len;
173 	}
174 
175 	/* add HT capability and information IEs */
176 	if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT &&
177 	    chandef->width != NL80211_CHAN_WIDTH_5 &&
178 	    chandef->width != NL80211_CHAN_WIDTH_10 &&
179 	    sband->ht_cap.ht_supported) {
180 		struct ieee80211_sta_ht_cap ht_cap;
181 
182 		memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
183 		ieee80211_apply_htcap_overrides(sdata, &ht_cap);
184 
185 		pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
186 		/*
187 		 * Note: According to 802.11n-2009 9.13.3.1, HT Protection
188 		 * field and RIFS Mode are reserved in IBSS mode, therefore
189 		 * keep them at 0
190 		 */
191 		pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
192 						 chandef, 0, false);
193 
194 		/* add VHT capability and information IEs */
195 		if (chandef->width != NL80211_CHAN_WIDTH_20 &&
196 		    chandef->width != NL80211_CHAN_WIDTH_40 &&
197 		    sband->vht_cap.vht_supported) {
198 			pos = ieee80211_ie_build_vht_cap(pos, &sband->vht_cap,
199 							 sband->vht_cap.cap);
200 			pos = ieee80211_ie_build_vht_oper(pos, &sband->vht_cap,
201 							  chandef);
202 		}
203 	}
204 
205 	if (local->hw.queues >= IEEE80211_NUM_ACS)
206 		pos = ieee80211_add_wmm_info_ie(pos, 0); /* U-APSD not in use */
207 
208 	presp->head_len = pos - presp->head;
209 	if (WARN_ON(presp->head_len > frame_len))
210 		goto error;
211 
212 	return presp;
213 error:
214 	kfree(presp);
215 	return NULL;
216 }
217 
218 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
219 				      const u8 *bssid, const int beacon_int,
220 				      struct cfg80211_chan_def *req_chandef,
221 				      const u32 basic_rates,
222 				      const u16 capability, u64 tsf,
223 				      bool creator)
224 {
225 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
226 	struct ieee80211_local *local = sdata->local;
227 	struct ieee80211_mgmt *mgmt;
228 	struct cfg80211_bss *bss;
229 	u32 bss_change;
230 	struct cfg80211_chan_def chandef;
231 	struct ieee80211_channel *chan;
232 	struct beacon_data *presp;
233 	struct cfg80211_inform_bss bss_meta = {};
234 	bool have_higher_than_11mbit;
235 	bool radar_required;
236 	int err;
237 
238 	sdata_assert_lock(sdata);
239 
240 	/* Reset own TSF to allow time synchronization work. */
241 	drv_reset_tsf(local, sdata);
242 
243 	if (!ether_addr_equal(ifibss->bssid, bssid))
244 		sta_info_flush(sdata);
245 
246 	/* if merging, indicate to driver that we leave the old IBSS */
247 	if (sdata->vif.bss_conf.ibss_joined) {
248 		sdata->vif.bss_conf.ibss_joined = false;
249 		sdata->vif.bss_conf.ibss_creator = false;
250 		sdata->vif.bss_conf.enable_beacon = false;
251 		netif_carrier_off(sdata->dev);
252 		ieee80211_bss_info_change_notify(sdata,
253 						 BSS_CHANGED_IBSS |
254 						 BSS_CHANGED_BEACON_ENABLED);
255 		drv_leave_ibss(local, sdata);
256 	}
257 
258 	presp = rcu_dereference_protected(ifibss->presp,
259 					  lockdep_is_held(&sdata->wdev.mtx));
260 	RCU_INIT_POINTER(ifibss->presp, NULL);
261 	if (presp)
262 		kfree_rcu(presp, rcu_head);
263 
264 	/* make a copy of the chandef, it could be modified below. */
265 	chandef = *req_chandef;
266 	chan = chandef.chan;
267 	if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
268 				     NL80211_IFTYPE_ADHOC)) {
269 		if (chandef.width == NL80211_CHAN_WIDTH_5 ||
270 		    chandef.width == NL80211_CHAN_WIDTH_10 ||
271 		    chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
272 		    chandef.width == NL80211_CHAN_WIDTH_20) {
273 			sdata_info(sdata,
274 				   "Failed to join IBSS, beacons forbidden\n");
275 			return;
276 		}
277 		chandef.width = NL80211_CHAN_WIDTH_20;
278 		chandef.center_freq1 = chan->center_freq;
279 		/* check again for downgraded chandef */
280 		if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
281 					     NL80211_IFTYPE_ADHOC)) {
282 			sdata_info(sdata,
283 				   "Failed to join IBSS, beacons forbidden\n");
284 			return;
285 		}
286 	}
287 
288 	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
289 					    &chandef, NL80211_IFTYPE_ADHOC);
290 	if (err < 0) {
291 		sdata_info(sdata,
292 			   "Failed to join IBSS, invalid chandef\n");
293 		return;
294 	}
295 	if (err > 0 && !ifibss->userspace_handles_dfs) {
296 		sdata_info(sdata,
297 			   "Failed to join IBSS, DFS channel without control program\n");
298 		return;
299 	}
300 
301 	radar_required = err;
302 
303 	mutex_lock(&local->mtx);
304 	if (ieee80211_vif_use_channel(sdata, &chandef,
305 				      ifibss->fixed_channel ?
306 					IEEE80211_CHANCTX_SHARED :
307 					IEEE80211_CHANCTX_EXCLUSIVE)) {
308 		sdata_info(sdata, "Failed to join IBSS, no channel context\n");
309 		mutex_unlock(&local->mtx);
310 		return;
311 	}
312 	sdata->radar_required = radar_required;
313 	mutex_unlock(&local->mtx);
314 
315 	memcpy(ifibss->bssid, bssid, ETH_ALEN);
316 
317 	presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
318 					   capability, tsf, &chandef,
319 					   &have_higher_than_11mbit, NULL);
320 	if (!presp)
321 		return;
322 
323 	rcu_assign_pointer(ifibss->presp, presp);
324 	mgmt = (void *)presp->head;
325 
326 	sdata->vif.bss_conf.enable_beacon = true;
327 	sdata->vif.bss_conf.beacon_int = beacon_int;
328 	sdata->vif.bss_conf.basic_rates = basic_rates;
329 	sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
330 	memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
331 	bss_change = BSS_CHANGED_BEACON_INT;
332 	bss_change |= ieee80211_reset_erp_info(sdata);
333 	bss_change |= BSS_CHANGED_BSSID;
334 	bss_change |= BSS_CHANGED_BEACON;
335 	bss_change |= BSS_CHANGED_BEACON_ENABLED;
336 	bss_change |= BSS_CHANGED_BASIC_RATES;
337 	bss_change |= BSS_CHANGED_HT;
338 	bss_change |= BSS_CHANGED_IBSS;
339 	bss_change |= BSS_CHANGED_SSID;
340 
341 	/*
342 	 * In 5 GHz/802.11a, we can always use short slot time.
343 	 * (IEEE 802.11-2012 18.3.8.7)
344 	 *
345 	 * In 2.4GHz, we must always use long slots in IBSS for compatibility
346 	 * reasons.
347 	 * (IEEE 802.11-2012 19.4.5)
348 	 *
349 	 * HT follows these specifications (IEEE 802.11-2012 20.3.18)
350 	 */
351 	sdata->vif.bss_conf.use_short_slot = chan->band == NL80211_BAND_5GHZ;
352 	bss_change |= BSS_CHANGED_ERP_SLOT;
353 
354 	/* cf. IEEE 802.11 9.2.12 */
355 	if (chan->band == NL80211_BAND_2GHZ && have_higher_than_11mbit)
356 		sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
357 	else
358 		sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
359 
360 	ieee80211_set_wmm_default(sdata, true, false);
361 
362 	sdata->vif.bss_conf.ibss_joined = true;
363 	sdata->vif.bss_conf.ibss_creator = creator;
364 
365 	err = drv_join_ibss(local, sdata);
366 	if (err) {
367 		sdata->vif.bss_conf.ibss_joined = false;
368 		sdata->vif.bss_conf.ibss_creator = false;
369 		sdata->vif.bss_conf.enable_beacon = false;
370 		sdata->vif.bss_conf.ssid_len = 0;
371 		RCU_INIT_POINTER(ifibss->presp, NULL);
372 		kfree_rcu(presp, rcu_head);
373 		mutex_lock(&local->mtx);
374 		ieee80211_vif_release_channel(sdata);
375 		mutex_unlock(&local->mtx);
376 		sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
377 			   err);
378 		return;
379 	}
380 
381 	ieee80211_bss_info_change_notify(sdata, bss_change);
382 
383 	ifibss->state = IEEE80211_IBSS_MLME_JOINED;
384 	mod_timer(&ifibss->timer,
385 		  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
386 
387 	bss_meta.chan = chan;
388 	bss_meta.scan_width = cfg80211_chandef_to_scan_width(&chandef);
389 	bss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta, mgmt,
390 					     presp->head_len, GFP_KERNEL);
391 
392 	cfg80211_put_bss(local->hw.wiphy, bss);
393 	netif_carrier_on(sdata->dev);
394 	cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
395 }
396 
397 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
398 				    struct ieee80211_bss *bss)
399 {
400 	struct cfg80211_bss *cbss =
401 		container_of((void *)bss, struct cfg80211_bss, priv);
402 	struct ieee80211_supported_band *sband;
403 	struct cfg80211_chan_def chandef;
404 	u32 basic_rates;
405 	int i, j;
406 	u16 beacon_int = cbss->beacon_interval;
407 	const struct cfg80211_bss_ies *ies;
408 	enum nl80211_channel_type chan_type;
409 	u64 tsf;
410 	u32 rate_flags;
411 	int shift;
412 
413 	sdata_assert_lock(sdata);
414 
415 	if (beacon_int < 10)
416 		beacon_int = 10;
417 
418 	switch (sdata->u.ibss.chandef.width) {
419 	case NL80211_CHAN_WIDTH_20_NOHT:
420 	case NL80211_CHAN_WIDTH_20:
421 	case NL80211_CHAN_WIDTH_40:
422 		chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
423 		cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
424 		break;
425 	case NL80211_CHAN_WIDTH_5:
426 	case NL80211_CHAN_WIDTH_10:
427 		cfg80211_chandef_create(&chandef, cbss->channel,
428 					NL80211_CHAN_NO_HT);
429 		chandef.width = sdata->u.ibss.chandef.width;
430 		break;
431 	case NL80211_CHAN_WIDTH_80:
432 	case NL80211_CHAN_WIDTH_80P80:
433 	case NL80211_CHAN_WIDTH_160:
434 		chandef = sdata->u.ibss.chandef;
435 		chandef.chan = cbss->channel;
436 		break;
437 	default:
438 		/* fall back to 20 MHz for unsupported modes */
439 		cfg80211_chandef_create(&chandef, cbss->channel,
440 					NL80211_CHAN_NO_HT);
441 		break;
442 	}
443 
444 	sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
445 	rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
446 	shift = ieee80211_vif_get_shift(&sdata->vif);
447 
448 	basic_rates = 0;
449 
450 	for (i = 0; i < bss->supp_rates_len; i++) {
451 		int rate = bss->supp_rates[i] & 0x7f;
452 		bool is_basic = !!(bss->supp_rates[i] & 0x80);
453 
454 		for (j = 0; j < sband->n_bitrates; j++) {
455 			int brate;
456 			if ((rate_flags & sband->bitrates[j].flags)
457 			    != rate_flags)
458 				continue;
459 
460 			brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
461 					     5 * (1 << shift));
462 			if (brate == rate) {
463 				if (is_basic)
464 					basic_rates |= BIT(j);
465 				break;
466 			}
467 		}
468 	}
469 
470 	rcu_read_lock();
471 	ies = rcu_dereference(cbss->ies);
472 	tsf = ies->tsf;
473 	rcu_read_unlock();
474 
475 	__ieee80211_sta_join_ibss(sdata, cbss->bssid,
476 				  beacon_int,
477 				  &chandef,
478 				  basic_rates,
479 				  cbss->capability,
480 				  tsf, false);
481 }
482 
483 int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
484 			      struct cfg80211_csa_settings *csa_settings)
485 {
486 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
487 	struct beacon_data *presp, *old_presp;
488 	struct cfg80211_bss *cbss;
489 	const struct cfg80211_bss_ies *ies;
490 	u16 capability = WLAN_CAPABILITY_IBSS;
491 	u64 tsf;
492 	int ret = 0;
493 
494 	sdata_assert_lock(sdata);
495 
496 	if (ifibss->privacy)
497 		capability |= WLAN_CAPABILITY_PRIVACY;
498 
499 	cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
500 				ifibss->bssid, ifibss->ssid,
501 				ifibss->ssid_len, IEEE80211_BSS_TYPE_IBSS,
502 				IEEE80211_PRIVACY(ifibss->privacy));
503 
504 	if (WARN_ON(!cbss)) {
505 		ret = -EINVAL;
506 		goto out;
507 	}
508 
509 	rcu_read_lock();
510 	ies = rcu_dereference(cbss->ies);
511 	tsf = ies->tsf;
512 	rcu_read_unlock();
513 	cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
514 
515 	old_presp = rcu_dereference_protected(ifibss->presp,
516 					  lockdep_is_held(&sdata->wdev.mtx));
517 
518 	presp = ieee80211_ibss_build_presp(sdata,
519 					   sdata->vif.bss_conf.beacon_int,
520 					   sdata->vif.bss_conf.basic_rates,
521 					   capability, tsf, &ifibss->chandef,
522 					   NULL, csa_settings);
523 	if (!presp) {
524 		ret = -ENOMEM;
525 		goto out;
526 	}
527 
528 	rcu_assign_pointer(ifibss->presp, presp);
529 	if (old_presp)
530 		kfree_rcu(old_presp, rcu_head);
531 
532 	return BSS_CHANGED_BEACON;
533  out:
534 	return ret;
535 }
536 
537 int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
538 {
539 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
540 	struct cfg80211_bss *cbss;
541 
542 	sdata_assert_lock(sdata);
543 
544 	/* update cfg80211 bss information with the new channel */
545 	if (!is_zero_ether_addr(ifibss->bssid)) {
546 		cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
547 					ifibss->chandef.chan,
548 					ifibss->bssid, ifibss->ssid,
549 					ifibss->ssid_len,
550 					IEEE80211_BSS_TYPE_IBSS,
551 					IEEE80211_PRIVACY(ifibss->privacy));
552 		/* XXX: should not really modify cfg80211 data */
553 		if (cbss) {
554 			cbss->channel = sdata->csa_chandef.chan;
555 			cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
556 		}
557 	}
558 
559 	ifibss->chandef = sdata->csa_chandef;
560 
561 	/* generate the beacon */
562 	return ieee80211_ibss_csa_beacon(sdata, NULL);
563 }
564 
565 void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
566 {
567 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
568 
569 	cancel_work_sync(&ifibss->csa_connection_drop_work);
570 }
571 
572 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
573 	__acquires(RCU)
574 {
575 	struct ieee80211_sub_if_data *sdata = sta->sdata;
576 	u8 addr[ETH_ALEN];
577 
578 	memcpy(addr, sta->sta.addr, ETH_ALEN);
579 
580 	ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
581 
582 	sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
583 	sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
584 	/* authorize the station only if the network is not RSN protected. If
585 	 * not wait for the userspace to authorize it */
586 	if (!sta->sdata->u.ibss.control_port)
587 		sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
588 
589 	rate_control_rate_init(sta);
590 
591 	/* If it fails, maybe we raced another insertion? */
592 	if (sta_info_insert_rcu(sta))
593 		return sta_info_get(sdata, addr);
594 	return sta;
595 }
596 
597 static struct sta_info *
598 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
599 		       const u8 *addr, u32 supp_rates)
600 	__acquires(RCU)
601 {
602 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
603 	struct ieee80211_local *local = sdata->local;
604 	struct sta_info *sta;
605 	struct ieee80211_chanctx_conf *chanctx_conf;
606 	struct ieee80211_supported_band *sband;
607 	enum nl80211_bss_scan_width scan_width;
608 	int band;
609 
610 	/*
611 	 * XXX: Consider removing the least recently used entry and
612 	 * 	allow new one to be added.
613 	 */
614 	if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
615 		net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
616 				    sdata->name, addr);
617 		rcu_read_lock();
618 		return NULL;
619 	}
620 
621 	if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
622 		rcu_read_lock();
623 		return NULL;
624 	}
625 
626 	if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
627 		rcu_read_lock();
628 		return NULL;
629 	}
630 
631 	rcu_read_lock();
632 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
633 	if (WARN_ON_ONCE(!chanctx_conf))
634 		return NULL;
635 	band = chanctx_conf->def.chan->band;
636 	scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
637 	rcu_read_unlock();
638 
639 	sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
640 	if (!sta) {
641 		rcu_read_lock();
642 		return NULL;
643 	}
644 
645 	/* make sure mandatory rates are always added */
646 	sband = local->hw.wiphy->bands[band];
647 	sta->sta.supp_rates[band] = supp_rates |
648 			ieee80211_mandatory_rates(sband, scan_width);
649 
650 	return ieee80211_ibss_finish_sta(sta);
651 }
652 
653 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
654 {
655 	struct ieee80211_local *local = sdata->local;
656 	int active = 0;
657 	struct sta_info *sta;
658 
659 	sdata_assert_lock(sdata);
660 
661 	rcu_read_lock();
662 
663 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
664 		unsigned long last_active = ieee80211_sta_last_active(sta);
665 
666 		if (sta->sdata == sdata &&
667 		    time_is_after_jiffies(last_active +
668 					  IEEE80211_IBSS_MERGE_INTERVAL)) {
669 			active++;
670 			break;
671 		}
672 	}
673 
674 	rcu_read_unlock();
675 
676 	return active;
677 }
678 
679 static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
680 {
681 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
682 	struct ieee80211_local *local = sdata->local;
683 	struct cfg80211_bss *cbss;
684 	struct beacon_data *presp;
685 	struct sta_info *sta;
686 
687 	if (!is_zero_ether_addr(ifibss->bssid)) {
688 		cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
689 					ifibss->bssid, ifibss->ssid,
690 					ifibss->ssid_len,
691 					IEEE80211_BSS_TYPE_IBSS,
692 					IEEE80211_PRIVACY(ifibss->privacy));
693 
694 		if (cbss) {
695 			cfg80211_unlink_bss(local->hw.wiphy, cbss);
696 			cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
697 		}
698 	}
699 
700 	ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
701 
702 	sta_info_flush(sdata);
703 
704 	spin_lock_bh(&ifibss->incomplete_lock);
705 	while (!list_empty(&ifibss->incomplete_stations)) {
706 		sta = list_first_entry(&ifibss->incomplete_stations,
707 				       struct sta_info, list);
708 		list_del(&sta->list);
709 		spin_unlock_bh(&ifibss->incomplete_lock);
710 
711 		sta_info_free(local, sta);
712 		spin_lock_bh(&ifibss->incomplete_lock);
713 	}
714 	spin_unlock_bh(&ifibss->incomplete_lock);
715 
716 	netif_carrier_off(sdata->dev);
717 
718 	sdata->vif.bss_conf.ibss_joined = false;
719 	sdata->vif.bss_conf.ibss_creator = false;
720 	sdata->vif.bss_conf.enable_beacon = false;
721 	sdata->vif.bss_conf.ssid_len = 0;
722 
723 	/* remove beacon */
724 	presp = rcu_dereference_protected(ifibss->presp,
725 					  lockdep_is_held(&sdata->wdev.mtx));
726 	RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
727 	if (presp)
728 		kfree_rcu(presp, rcu_head);
729 
730 	clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
731 	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
732 						BSS_CHANGED_IBSS);
733 	drv_leave_ibss(local, sdata);
734 	mutex_lock(&local->mtx);
735 	ieee80211_vif_release_channel(sdata);
736 	mutex_unlock(&local->mtx);
737 }
738 
739 static void ieee80211_csa_connection_drop_work(struct work_struct *work)
740 {
741 	struct ieee80211_sub_if_data *sdata =
742 		container_of(work, struct ieee80211_sub_if_data,
743 			     u.ibss.csa_connection_drop_work);
744 
745 	sdata_lock(sdata);
746 
747 	ieee80211_ibss_disconnect(sdata);
748 	synchronize_rcu();
749 	skb_queue_purge(&sdata->skb_queue);
750 
751 	/* trigger a scan to find another IBSS network to join */
752 	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
753 
754 	sdata_unlock(sdata);
755 }
756 
757 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
758 {
759 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
760 	int err;
761 
762 	/* if the current channel is a DFS channel, mark the channel as
763 	 * unavailable.
764 	 */
765 	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
766 					    &ifibss->chandef,
767 					    NL80211_IFTYPE_ADHOC);
768 	if (err > 0)
769 		cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
770 				     GFP_ATOMIC);
771 }
772 
773 static bool
774 ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
775 				  struct ieee802_11_elems *elems,
776 				  bool beacon)
777 {
778 	struct cfg80211_csa_settings params;
779 	struct ieee80211_csa_ie csa_ie;
780 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
781 	enum nl80211_channel_type ch_type;
782 	int err;
783 	u32 sta_flags;
784 	u32 vht_cap_info = 0;
785 
786 	sdata_assert_lock(sdata);
787 
788 	sta_flags = IEEE80211_STA_DISABLE_VHT;
789 	switch (ifibss->chandef.width) {
790 	case NL80211_CHAN_WIDTH_5:
791 	case NL80211_CHAN_WIDTH_10:
792 	case NL80211_CHAN_WIDTH_20_NOHT:
793 		sta_flags |= IEEE80211_STA_DISABLE_HT;
794 		/* fall through */
795 	case NL80211_CHAN_WIDTH_20:
796 		sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
797 		break;
798 	default:
799 		break;
800 	}
801 
802 	if (elems->vht_cap_elem)
803 		vht_cap_info = le32_to_cpu(elems->vht_cap_elem->vht_cap_info);
804 
805 	memset(&params, 0, sizeof(params));
806 	err = ieee80211_parse_ch_switch_ie(sdata, elems,
807 					   ifibss->chandef.chan->band,
808 					   vht_cap_info,
809 					   sta_flags, ifibss->bssid, &csa_ie);
810 	/* can't switch to destination channel, fail */
811 	if (err < 0)
812 		goto disconnect;
813 
814 	/* did not contain a CSA */
815 	if (err)
816 		return false;
817 
818 	/* channel switch is not supported, disconnect */
819 	if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
820 		goto disconnect;
821 
822 	params.count = csa_ie.count;
823 	params.chandef = csa_ie.chandef;
824 
825 	switch (ifibss->chandef.width) {
826 	case NL80211_CHAN_WIDTH_20_NOHT:
827 	case NL80211_CHAN_WIDTH_20:
828 	case NL80211_CHAN_WIDTH_40:
829 		/* keep our current HT mode (HT20/HT40+/HT40-), even if
830 		 * another mode  has been announced. The mode is not adopted
831 		 * within the beacon while doing CSA and we should therefore
832 		 * keep the mode which we announce.
833 		 */
834 		ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
835 		cfg80211_chandef_create(&params.chandef, params.chandef.chan,
836 					ch_type);
837 		break;
838 	case NL80211_CHAN_WIDTH_5:
839 	case NL80211_CHAN_WIDTH_10:
840 		if (params.chandef.width != ifibss->chandef.width) {
841 			sdata_info(sdata,
842 				   "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
843 				   ifibss->bssid,
844 				   params.chandef.chan->center_freq,
845 				   params.chandef.width,
846 				   params.chandef.center_freq1,
847 				   params.chandef.center_freq2);
848 			goto disconnect;
849 		}
850 		break;
851 	default:
852 		/* should not happen, sta_flags should prevent VHT modes. */
853 		WARN_ON(1);
854 		goto disconnect;
855 	}
856 
857 	if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef,
858 				     NL80211_IFTYPE_ADHOC)) {
859 		sdata_info(sdata,
860 			   "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
861 			   ifibss->bssid,
862 			   params.chandef.chan->center_freq,
863 			   params.chandef.width,
864 			   params.chandef.center_freq1,
865 			   params.chandef.center_freq2);
866 		goto disconnect;
867 	}
868 
869 	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
870 					    &params.chandef,
871 					    NL80211_IFTYPE_ADHOC);
872 	if (err < 0)
873 		goto disconnect;
874 	if (err > 0 && !ifibss->userspace_handles_dfs) {
875 		/* IBSS-DFS only allowed with a control program */
876 		goto disconnect;
877 	}
878 
879 	params.radar_required = err;
880 
881 	if (cfg80211_chandef_identical(&params.chandef,
882 				       &sdata->vif.bss_conf.chandef)) {
883 		ibss_dbg(sdata,
884 			 "received csa with an identical chandef, ignoring\n");
885 		return true;
886 	}
887 
888 	/* all checks done, now perform the channel switch. */
889 	ibss_dbg(sdata,
890 		 "received channel switch announcement to go to channel %d MHz\n",
891 		 params.chandef.chan->center_freq);
892 
893 	params.block_tx = !!csa_ie.mode;
894 
895 	if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
896 				     &params))
897 		goto disconnect;
898 
899 	ieee80211_ibss_csa_mark_radar(sdata);
900 
901 	return true;
902 disconnect:
903 	ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
904 	ieee80211_queue_work(&sdata->local->hw,
905 			     &ifibss->csa_connection_drop_work);
906 
907 	ieee80211_ibss_csa_mark_radar(sdata);
908 
909 	return true;
910 }
911 
912 static void
913 ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
914 				struct ieee80211_mgmt *mgmt, size_t len,
915 				struct ieee80211_rx_status *rx_status,
916 				struct ieee802_11_elems *elems)
917 {
918 	int required_len;
919 
920 	if (len < IEEE80211_MIN_ACTION_SIZE + 1)
921 		return;
922 
923 	/* CSA is the only action we handle for now */
924 	if (mgmt->u.action.u.measurement.action_code !=
925 	    WLAN_ACTION_SPCT_CHL_SWITCH)
926 		return;
927 
928 	required_len = IEEE80211_MIN_ACTION_SIZE +
929 		       sizeof(mgmt->u.action.u.chan_switch);
930 	if (len < required_len)
931 		return;
932 
933 	if (!sdata->vif.csa_active)
934 		ieee80211_ibss_process_chanswitch(sdata, elems, false);
935 }
936 
937 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
938 					  struct ieee80211_mgmt *mgmt,
939 					  size_t len)
940 {
941 	u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
942 
943 	if (len < IEEE80211_DEAUTH_FRAME_LEN)
944 		return;
945 
946 	ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
947 	ibss_dbg(sdata, "\tBSSID=%pM (reason: %d)\n", mgmt->bssid, reason);
948 	sta_info_destroy_addr(sdata, mgmt->sa);
949 }
950 
951 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
952 					struct ieee80211_mgmt *mgmt,
953 					size_t len)
954 {
955 	u16 auth_alg, auth_transaction;
956 
957 	sdata_assert_lock(sdata);
958 
959 	if (len < 24 + 6)
960 		return;
961 
962 	auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
963 	auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
964 
965 	ibss_dbg(sdata, "RX Auth SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
966 	ibss_dbg(sdata, "\tBSSID=%pM (auth_transaction=%d)\n",
967 		 mgmt->bssid, auth_transaction);
968 
969 	if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
970 		return;
971 
972 	/*
973 	 * IEEE 802.11 standard does not require authentication in IBSS
974 	 * networks and most implementations do not seem to use it.
975 	 * However, try to reply to authentication attempts if someone
976 	 * has actually implemented this.
977 	 */
978 	ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
979 			    mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
980 }
981 
982 static void ieee80211_update_sta_info(struct ieee80211_sub_if_data *sdata,
983 				      struct ieee80211_mgmt *mgmt, size_t len,
984 				      struct ieee80211_rx_status *rx_status,
985 				      struct ieee802_11_elems *elems,
986 				      struct ieee80211_channel *channel)
987 {
988 	struct sta_info *sta;
989 	enum nl80211_band band = rx_status->band;
990 	enum nl80211_bss_scan_width scan_width;
991 	struct ieee80211_local *local = sdata->local;
992 	struct ieee80211_supported_band *sband;
993 	bool rates_updated = false;
994 	u32 supp_rates = 0;
995 
996 	if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
997 		return;
998 
999 	if (!ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid))
1000 		return;
1001 
1002 	sband = local->hw.wiphy->bands[band];
1003 	if (WARN_ON(!sband))
1004 		return;
1005 
1006 	rcu_read_lock();
1007 	sta = sta_info_get(sdata, mgmt->sa);
1008 
1009 	if (elems->supp_rates) {
1010 		supp_rates = ieee80211_sta_get_rates(sdata, elems,
1011 						     band, NULL);
1012 		if (sta) {
1013 			u32 prev_rates;
1014 
1015 			prev_rates = sta->sta.supp_rates[band];
1016 			/* make sure mandatory rates are always added */
1017 			scan_width = NL80211_BSS_CHAN_WIDTH_20;
1018 			if (rx_status->bw == RATE_INFO_BW_5)
1019 				scan_width = NL80211_BSS_CHAN_WIDTH_5;
1020 			else if (rx_status->bw == RATE_INFO_BW_10)
1021 				scan_width = NL80211_BSS_CHAN_WIDTH_10;
1022 
1023 			sta->sta.supp_rates[band] = supp_rates |
1024 				ieee80211_mandatory_rates(sband, scan_width);
1025 			if (sta->sta.supp_rates[band] != prev_rates) {
1026 				ibss_dbg(sdata,
1027 					 "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
1028 					 sta->sta.addr, prev_rates,
1029 					 sta->sta.supp_rates[band]);
1030 				rates_updated = true;
1031 			}
1032 		} else {
1033 			rcu_read_unlock();
1034 			sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
1035 						     mgmt->sa, supp_rates);
1036 		}
1037 	}
1038 
1039 	if (sta && !sta->sta.wme &&
1040 	    elems->wmm_info && local->hw.queues >= IEEE80211_NUM_ACS) {
1041 		sta->sta.wme = true;
1042 		ieee80211_check_fast_xmit(sta);
1043 	}
1044 
1045 	if (sta && elems->ht_operation && elems->ht_cap_elem &&
1046 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
1047 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
1048 	    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
1049 		/* we both use HT */
1050 		struct ieee80211_ht_cap htcap_ie;
1051 		struct cfg80211_chan_def chandef;
1052 		enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth;
1053 
1054 		cfg80211_chandef_create(&chandef, channel, NL80211_CHAN_NO_HT);
1055 		ieee80211_chandef_ht_oper(elems->ht_operation, &chandef);
1056 
1057 		memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
1058 		rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
1059 								   &htcap_ie,
1060 								   sta);
1061 
1062 		if (elems->vht_operation && elems->vht_cap_elem &&
1063 		    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20 &&
1064 		    sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_40) {
1065 			/* we both use VHT */
1066 			struct ieee80211_vht_cap cap_ie;
1067 			struct ieee80211_sta_vht_cap cap = sta->sta.vht_cap;
1068 			u32 vht_cap_info =
1069 				le32_to_cpu(elems->vht_cap_elem->vht_cap_info);
1070 
1071 			ieee80211_chandef_vht_oper(&local->hw, vht_cap_info,
1072 						   elems->vht_operation,
1073 						   elems->ht_operation,
1074 						   &chandef);
1075 			memcpy(&cap_ie, elems->vht_cap_elem, sizeof(cap_ie));
1076 			ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
1077 							    &cap_ie, sta);
1078 			if (memcmp(&cap, &sta->sta.vht_cap, sizeof(cap)))
1079 				rates_updated |= true;
1080 		}
1081 
1082 		if (bw != sta->sta.bandwidth)
1083 			rates_updated |= true;
1084 
1085 		if (!cfg80211_chandef_compatible(&sdata->u.ibss.chandef,
1086 						 &chandef))
1087 			WARN_ON_ONCE(1);
1088 	}
1089 
1090 	if (sta && rates_updated) {
1091 		u32 changed = IEEE80211_RC_SUPP_RATES_CHANGED;
1092 		u8 rx_nss = sta->sta.rx_nss;
1093 
1094 		/* Force rx_nss recalculation */
1095 		sta->sta.rx_nss = 0;
1096 		rate_control_rate_init(sta);
1097 		if (sta->sta.rx_nss != rx_nss)
1098 			changed |= IEEE80211_RC_NSS_CHANGED;
1099 
1100 		drv_sta_rc_update(local, sdata, &sta->sta, changed);
1101 	}
1102 
1103 	rcu_read_unlock();
1104 }
1105 
1106 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
1107 				  struct ieee80211_mgmt *mgmt, size_t len,
1108 				  struct ieee80211_rx_status *rx_status,
1109 				  struct ieee802_11_elems *elems)
1110 {
1111 	struct ieee80211_local *local = sdata->local;
1112 	struct cfg80211_bss *cbss;
1113 	struct ieee80211_bss *bss;
1114 	struct ieee80211_channel *channel;
1115 	u64 beacon_timestamp, rx_timestamp;
1116 	u32 supp_rates = 0;
1117 	enum nl80211_band band = rx_status->band;
1118 
1119 	channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
1120 	if (!channel)
1121 		return;
1122 
1123 	ieee80211_update_sta_info(sdata, mgmt, len, rx_status, elems, channel);
1124 
1125 	bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, channel);
1126 	if (!bss)
1127 		return;
1128 
1129 	cbss = container_of((void *)bss, struct cfg80211_bss, priv);
1130 
1131 	/* same for beacon and probe response */
1132 	beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
1133 
1134 	/* check if we need to merge IBSS */
1135 
1136 	/* not an IBSS */
1137 	if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
1138 		goto put_bss;
1139 
1140 	/* different channel */
1141 	if (sdata->u.ibss.fixed_channel &&
1142 	    sdata->u.ibss.chandef.chan != cbss->channel)
1143 		goto put_bss;
1144 
1145 	/* different SSID */
1146 	if (elems->ssid_len != sdata->u.ibss.ssid_len ||
1147 	    memcmp(elems->ssid, sdata->u.ibss.ssid,
1148 				sdata->u.ibss.ssid_len))
1149 		goto put_bss;
1150 
1151 	/* process channel switch */
1152 	if (sdata->vif.csa_active ||
1153 	    ieee80211_ibss_process_chanswitch(sdata, elems, true))
1154 		goto put_bss;
1155 
1156 	/* same BSSID */
1157 	if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
1158 		goto put_bss;
1159 
1160 	/* we use a fixed BSSID */
1161 	if (sdata->u.ibss.fixed_bssid)
1162 		goto put_bss;
1163 
1164 	if (ieee80211_have_rx_timestamp(rx_status)) {
1165 		/* time when timestamp field was received */
1166 		rx_timestamp =
1167 			ieee80211_calculate_rx_timestamp(local, rx_status,
1168 							 len + FCS_LEN, 24);
1169 	} else {
1170 		/*
1171 		 * second best option: get current TSF
1172 		 * (will return -1 if not supported)
1173 		 */
1174 		rx_timestamp = drv_get_tsf(local, sdata);
1175 	}
1176 
1177 	ibss_dbg(sdata, "RX beacon SA=%pM BSSID=%pM TSF=0x%llx\n",
1178 		 mgmt->sa, mgmt->bssid,
1179 		 (unsigned long long)rx_timestamp);
1180 	ibss_dbg(sdata, "\tBCN=0x%llx diff=%lld @%lu\n",
1181 		 (unsigned long long)beacon_timestamp,
1182 		 (unsigned long long)(rx_timestamp - beacon_timestamp),
1183 		 jiffies);
1184 
1185 	if (beacon_timestamp > rx_timestamp) {
1186 		ibss_dbg(sdata,
1187 			 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
1188 			 mgmt->bssid);
1189 		ieee80211_sta_join_ibss(sdata, bss);
1190 		supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
1191 		ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
1192 				       supp_rates);
1193 		rcu_read_unlock();
1194 	}
1195 
1196  put_bss:
1197 	ieee80211_rx_bss_put(local, bss);
1198 }
1199 
1200 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
1201 			      const u8 *bssid, const u8 *addr,
1202 			      u32 supp_rates)
1203 {
1204 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1205 	struct ieee80211_local *local = sdata->local;
1206 	struct sta_info *sta;
1207 	struct ieee80211_chanctx_conf *chanctx_conf;
1208 	struct ieee80211_supported_band *sband;
1209 	enum nl80211_bss_scan_width scan_width;
1210 	int band;
1211 
1212 	/*
1213 	 * XXX: Consider removing the least recently used entry and
1214 	 * 	allow new one to be added.
1215 	 */
1216 	if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
1217 		net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
1218 				    sdata->name, addr);
1219 		return;
1220 	}
1221 
1222 	if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
1223 		return;
1224 
1225 	if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
1226 		return;
1227 
1228 	rcu_read_lock();
1229 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1230 	if (WARN_ON_ONCE(!chanctx_conf)) {
1231 		rcu_read_unlock();
1232 		return;
1233 	}
1234 	band = chanctx_conf->def.chan->band;
1235 	scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
1236 	rcu_read_unlock();
1237 
1238 	sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
1239 	if (!sta)
1240 		return;
1241 
1242 	/* make sure mandatory rates are always added */
1243 	sband = local->hw.wiphy->bands[band];
1244 	sta->sta.supp_rates[band] = supp_rates |
1245 			ieee80211_mandatory_rates(sband, scan_width);
1246 
1247 	spin_lock(&ifibss->incomplete_lock);
1248 	list_add(&sta->list, &ifibss->incomplete_stations);
1249 	spin_unlock(&ifibss->incomplete_lock);
1250 	ieee80211_queue_work(&local->hw, &sdata->work);
1251 }
1252 
1253 static void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata)
1254 {
1255 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1256 	struct ieee80211_local *local = sdata->local;
1257 	struct sta_info *sta, *tmp;
1258 	unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT;
1259 	unsigned long exp_rsn = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT;
1260 
1261 	mutex_lock(&local->sta_mtx);
1262 
1263 	list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1264 		unsigned long last_active = ieee80211_sta_last_active(sta);
1265 
1266 		if (sdata != sta->sdata)
1267 			continue;
1268 
1269 		if (time_is_before_jiffies(last_active + exp_time) ||
1270 		    (time_is_before_jiffies(last_active + exp_rsn) &&
1271 		     sta->sta_state != IEEE80211_STA_AUTHORIZED)) {
1272 			u8 frame_buf[IEEE80211_DEAUTH_FRAME_LEN];
1273 
1274 			sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n",
1275 				sta->sta_state != IEEE80211_STA_AUTHORIZED ?
1276 				"not authorized " : "", sta->sta.addr);
1277 
1278 			ieee80211_send_deauth_disassoc(sdata, sta->sta.addr,
1279 						       ifibss->bssid,
1280 						       IEEE80211_STYPE_DEAUTH,
1281 						       WLAN_REASON_DEAUTH_LEAVING,
1282 						       true, frame_buf);
1283 			WARN_ON(__sta_info_destroy(sta));
1284 		}
1285 	}
1286 
1287 	mutex_unlock(&local->sta_mtx);
1288 }
1289 
1290 /*
1291  * This function is called with state == IEEE80211_IBSS_MLME_JOINED
1292  */
1293 
1294 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
1295 {
1296 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1297 	enum nl80211_bss_scan_width scan_width;
1298 
1299 	sdata_assert_lock(sdata);
1300 
1301 	mod_timer(&ifibss->timer,
1302 		  round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
1303 
1304 	ieee80211_ibss_sta_expire(sdata);
1305 
1306 	if (time_before(jiffies, ifibss->last_scan_completed +
1307 		       IEEE80211_IBSS_MERGE_INTERVAL))
1308 		return;
1309 
1310 	if (ieee80211_sta_active_ibss(sdata))
1311 		return;
1312 
1313 	if (ifibss->fixed_channel)
1314 		return;
1315 
1316 	sdata_info(sdata,
1317 		   "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
1318 
1319 	scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1320 	ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
1321 				    NULL, 0, scan_width);
1322 }
1323 
1324 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
1325 {
1326 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1327 	u8 bssid[ETH_ALEN];
1328 	u16 capability;
1329 	int i;
1330 
1331 	sdata_assert_lock(sdata);
1332 
1333 	if (ifibss->fixed_bssid) {
1334 		memcpy(bssid, ifibss->bssid, ETH_ALEN);
1335 	} else {
1336 		/* Generate random, not broadcast, locally administered BSSID. Mix in
1337 		 * own MAC address to make sure that devices that do not have proper
1338 		 * random number generator get different BSSID. */
1339 		get_random_bytes(bssid, ETH_ALEN);
1340 		for (i = 0; i < ETH_ALEN; i++)
1341 			bssid[i] ^= sdata->vif.addr[i];
1342 		bssid[0] &= ~0x01;
1343 		bssid[0] |= 0x02;
1344 	}
1345 
1346 	sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
1347 
1348 	capability = WLAN_CAPABILITY_IBSS;
1349 
1350 	if (ifibss->privacy)
1351 		capability |= WLAN_CAPABILITY_PRIVACY;
1352 
1353 	__ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
1354 				  &ifibss->chandef, ifibss->basic_rates,
1355 				  capability, 0, true);
1356 }
1357 
1358 static unsigned ibss_setup_channels(struct wiphy *wiphy,
1359 				    struct ieee80211_channel **channels,
1360 				    unsigned int channels_max,
1361 				    u32 center_freq, u32 width)
1362 {
1363 	struct ieee80211_channel *chan = NULL;
1364 	unsigned int n_chan = 0;
1365 	u32 start_freq, end_freq, freq;
1366 
1367 	if (width <= 20) {
1368 		start_freq = center_freq;
1369 		end_freq = center_freq;
1370 	} else {
1371 		start_freq = center_freq - width / 2 + 10;
1372 		end_freq = center_freq + width / 2 - 10;
1373 	}
1374 
1375 	for (freq = start_freq; freq <= end_freq; freq += 20) {
1376 		chan = ieee80211_get_channel(wiphy, freq);
1377 		if (!chan)
1378 			continue;
1379 		if (n_chan >= channels_max)
1380 			return n_chan;
1381 
1382 		channels[n_chan] = chan;
1383 		n_chan++;
1384 	}
1385 
1386 	return n_chan;
1387 }
1388 
1389 static unsigned int
1390 ieee80211_ibss_setup_scan_channels(struct wiphy *wiphy,
1391 				   const struct cfg80211_chan_def *chandef,
1392 				   struct ieee80211_channel **channels,
1393 				   unsigned int channels_max)
1394 {
1395 	unsigned int n_chan = 0;
1396 	u32 width, cf1, cf2 = 0;
1397 
1398 	switch (chandef->width) {
1399 	case NL80211_CHAN_WIDTH_40:
1400 		width = 40;
1401 		break;
1402 	case NL80211_CHAN_WIDTH_80P80:
1403 		cf2 = chandef->center_freq2;
1404 		/* fall through */
1405 	case NL80211_CHAN_WIDTH_80:
1406 		width = 80;
1407 		break;
1408 	case NL80211_CHAN_WIDTH_160:
1409 		width = 160;
1410 		break;
1411 	default:
1412 		width = 20;
1413 		break;
1414 	}
1415 
1416 	cf1 = chandef->center_freq1;
1417 
1418 	n_chan = ibss_setup_channels(wiphy, channels, channels_max, cf1, width);
1419 
1420 	if (cf2)
1421 		n_chan += ibss_setup_channels(wiphy, &channels[n_chan],
1422 					      channels_max - n_chan, cf2,
1423 					      width);
1424 
1425 	return n_chan;
1426 }
1427 
1428 /*
1429  * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
1430  */
1431 
1432 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
1433 {
1434 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1435 	struct ieee80211_local *local = sdata->local;
1436 	struct cfg80211_bss *cbss;
1437 	struct ieee80211_channel *chan = NULL;
1438 	const u8 *bssid = NULL;
1439 	enum nl80211_bss_scan_width scan_width;
1440 	int active_ibss;
1441 
1442 	sdata_assert_lock(sdata);
1443 
1444 	active_ibss = ieee80211_sta_active_ibss(sdata);
1445 	ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
1446 
1447 	if (active_ibss)
1448 		return;
1449 
1450 	if (ifibss->fixed_bssid)
1451 		bssid = ifibss->bssid;
1452 	if (ifibss->fixed_channel)
1453 		chan = ifibss->chandef.chan;
1454 	if (!is_zero_ether_addr(ifibss->bssid))
1455 		bssid = ifibss->bssid;
1456 	cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
1457 				ifibss->ssid, ifibss->ssid_len,
1458 				IEEE80211_BSS_TYPE_IBSS,
1459 				IEEE80211_PRIVACY(ifibss->privacy));
1460 
1461 	if (cbss) {
1462 		struct ieee80211_bss *bss;
1463 
1464 		bss = (void *)cbss->priv;
1465 		ibss_dbg(sdata,
1466 			 "sta_find_ibss: selected %pM current %pM\n",
1467 			 cbss->bssid, ifibss->bssid);
1468 		sdata_info(sdata,
1469 			   "Selected IBSS BSSID %pM based on configured SSID\n",
1470 			   cbss->bssid);
1471 
1472 		ieee80211_sta_join_ibss(sdata, bss);
1473 		ieee80211_rx_bss_put(local, bss);
1474 		return;
1475 	}
1476 
1477 	/* if a fixed bssid and a fixed freq have been provided create the IBSS
1478 	 * directly and do not waste time scanning
1479 	 */
1480 	if (ifibss->fixed_bssid && ifibss->fixed_channel) {
1481 		sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n",
1482 			   bssid);
1483 		ieee80211_sta_create_ibss(sdata);
1484 		return;
1485 	}
1486 
1487 
1488 	ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
1489 
1490 	/* Selected IBSS not found in current scan results - try to scan */
1491 	if (time_after(jiffies, ifibss->last_scan_completed +
1492 					IEEE80211_SCAN_INTERVAL)) {
1493 		struct ieee80211_channel *channels[8];
1494 		unsigned int num;
1495 
1496 		sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
1497 
1498 		scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
1499 
1500 		if (ifibss->fixed_channel) {
1501 			num = ieee80211_ibss_setup_scan_channels(local->hw.wiphy,
1502 								 &ifibss->chandef,
1503 								 channels,
1504 								 ARRAY_SIZE(channels));
1505 			ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1506 						    ifibss->ssid_len, channels,
1507 						    num, scan_width);
1508 		} else {
1509 			ieee80211_request_ibss_scan(sdata, ifibss->ssid,
1510 						    ifibss->ssid_len, NULL,
1511 						    0, scan_width);
1512 		}
1513 	} else {
1514 		int interval = IEEE80211_SCAN_INTERVAL;
1515 
1516 		if (time_after(jiffies, ifibss->ibss_join_req +
1517 			       IEEE80211_IBSS_JOIN_TIMEOUT))
1518 			ieee80211_sta_create_ibss(sdata);
1519 
1520 		mod_timer(&ifibss->timer,
1521 			  round_jiffies(jiffies + interval));
1522 	}
1523 }
1524 
1525 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
1526 					struct sk_buff *req)
1527 {
1528 	struct ieee80211_mgmt *mgmt = (void *)req->data;
1529 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1530 	struct ieee80211_local *local = sdata->local;
1531 	int tx_last_beacon, len = req->len;
1532 	struct sk_buff *skb;
1533 	struct beacon_data *presp;
1534 	u8 *pos, *end;
1535 
1536 	sdata_assert_lock(sdata);
1537 
1538 	presp = rcu_dereference_protected(ifibss->presp,
1539 					  lockdep_is_held(&sdata->wdev.mtx));
1540 
1541 	if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
1542 	    len < 24 + 2 || !presp)
1543 		return;
1544 
1545 	tx_last_beacon = drv_tx_last_beacon(local);
1546 
1547 	ibss_dbg(sdata, "RX ProbeReq SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
1548 	ibss_dbg(sdata, "\tBSSID=%pM (tx_last_beacon=%d)\n",
1549 		 mgmt->bssid, tx_last_beacon);
1550 
1551 	if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
1552 		return;
1553 
1554 	if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
1555 	    !is_broadcast_ether_addr(mgmt->bssid))
1556 		return;
1557 
1558 	end = ((u8 *) mgmt) + len;
1559 	pos = mgmt->u.probe_req.variable;
1560 	if (pos[0] != WLAN_EID_SSID ||
1561 	    pos + 2 + pos[1] > end) {
1562 		ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
1563 			 mgmt->sa);
1564 		return;
1565 	}
1566 	if (pos[1] != 0 &&
1567 	    (pos[1] != ifibss->ssid_len ||
1568 	     memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
1569 		/* Ignore ProbeReq for foreign SSID */
1570 		return;
1571 	}
1572 
1573 	/* Reply with ProbeResp */
1574 	skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
1575 	if (!skb)
1576 		return;
1577 
1578 	skb_reserve(skb, local->tx_headroom);
1579 	skb_put_data(skb, presp->head, presp->head_len);
1580 
1581 	memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
1582 	ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
1583 	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
1584 
1585 	/* avoid excessive retries for probe request to wildcard SSIDs */
1586 	if (pos[1] == 0)
1587 		IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK;
1588 
1589 	ieee80211_tx_skb(sdata, skb);
1590 }
1591 
1592 static
1593 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
1594 				    struct ieee80211_mgmt *mgmt, size_t len,
1595 				    struct ieee80211_rx_status *rx_status)
1596 {
1597 	size_t baselen;
1598 	struct ieee802_11_elems elems;
1599 
1600 	BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
1601 		     offsetof(typeof(mgmt->u.beacon), variable));
1602 
1603 	/*
1604 	 * either beacon or probe_resp but the variable field is at the
1605 	 * same offset
1606 	 */
1607 	baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
1608 	if (baselen > len)
1609 		return;
1610 
1611 	ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
1612 			       false, &elems, mgmt->bssid, NULL);
1613 
1614 	ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
1615 }
1616 
1617 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
1618 				   struct sk_buff *skb)
1619 {
1620 	struct ieee80211_rx_status *rx_status;
1621 	struct ieee80211_mgmt *mgmt;
1622 	u16 fc;
1623 	struct ieee802_11_elems elems;
1624 	int ies_len;
1625 
1626 	rx_status = IEEE80211_SKB_RXCB(skb);
1627 	mgmt = (struct ieee80211_mgmt *) skb->data;
1628 	fc = le16_to_cpu(mgmt->frame_control);
1629 
1630 	sdata_lock(sdata);
1631 
1632 	if (!sdata->u.ibss.ssid_len)
1633 		goto mgmt_out; /* not ready to merge yet */
1634 
1635 	switch (fc & IEEE80211_FCTL_STYPE) {
1636 	case IEEE80211_STYPE_PROBE_REQ:
1637 		ieee80211_rx_mgmt_probe_req(sdata, skb);
1638 		break;
1639 	case IEEE80211_STYPE_PROBE_RESP:
1640 	case IEEE80211_STYPE_BEACON:
1641 		ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
1642 					       rx_status);
1643 		break;
1644 	case IEEE80211_STYPE_AUTH:
1645 		ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
1646 		break;
1647 	case IEEE80211_STYPE_DEAUTH:
1648 		ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
1649 		break;
1650 	case IEEE80211_STYPE_ACTION:
1651 		switch (mgmt->u.action.category) {
1652 		case WLAN_CATEGORY_SPECTRUM_MGMT:
1653 			ies_len = skb->len -
1654 				  offsetof(struct ieee80211_mgmt,
1655 					   u.action.u.chan_switch.variable);
1656 
1657 			if (ies_len < 0)
1658 				break;
1659 
1660 			ieee802_11_parse_elems(
1661 				mgmt->u.action.u.chan_switch.variable,
1662 				ies_len, true, &elems, mgmt->bssid, NULL);
1663 
1664 			if (elems.parse_error)
1665 				break;
1666 
1667 			ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
1668 							rx_status, &elems);
1669 			break;
1670 		}
1671 	}
1672 
1673  mgmt_out:
1674 	sdata_unlock(sdata);
1675 }
1676 
1677 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
1678 {
1679 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1680 	struct sta_info *sta;
1681 
1682 	sdata_lock(sdata);
1683 
1684 	/*
1685 	 * Work could be scheduled after scan or similar
1686 	 * when we aren't even joined (or trying) with a
1687 	 * network.
1688 	 */
1689 	if (!ifibss->ssid_len)
1690 		goto out;
1691 
1692 	spin_lock_bh(&ifibss->incomplete_lock);
1693 	while (!list_empty(&ifibss->incomplete_stations)) {
1694 		sta = list_first_entry(&ifibss->incomplete_stations,
1695 				       struct sta_info, list);
1696 		list_del(&sta->list);
1697 		spin_unlock_bh(&ifibss->incomplete_lock);
1698 
1699 		ieee80211_ibss_finish_sta(sta);
1700 		rcu_read_unlock();
1701 		spin_lock_bh(&ifibss->incomplete_lock);
1702 	}
1703 	spin_unlock_bh(&ifibss->incomplete_lock);
1704 
1705 	switch (ifibss->state) {
1706 	case IEEE80211_IBSS_MLME_SEARCH:
1707 		ieee80211_sta_find_ibss(sdata);
1708 		break;
1709 	case IEEE80211_IBSS_MLME_JOINED:
1710 		ieee80211_sta_merge_ibss(sdata);
1711 		break;
1712 	default:
1713 		WARN_ON(1);
1714 		break;
1715 	}
1716 
1717  out:
1718 	sdata_unlock(sdata);
1719 }
1720 
1721 static void ieee80211_ibss_timer(struct timer_list *t)
1722 {
1723 	struct ieee80211_sub_if_data *sdata =
1724 		from_timer(sdata, t, u.ibss.timer);
1725 
1726 	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1727 }
1728 
1729 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1730 {
1731 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1732 
1733 	timer_setup(&ifibss->timer, ieee80211_ibss_timer, 0);
1734 	INIT_LIST_HEAD(&ifibss->incomplete_stations);
1735 	spin_lock_init(&ifibss->incomplete_lock);
1736 	INIT_WORK(&ifibss->csa_connection_drop_work,
1737 		  ieee80211_csa_connection_drop_work);
1738 }
1739 
1740 /* scan finished notification */
1741 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1742 {
1743 	struct ieee80211_sub_if_data *sdata;
1744 
1745 	mutex_lock(&local->iflist_mtx);
1746 	list_for_each_entry(sdata, &local->interfaces, list) {
1747 		if (!ieee80211_sdata_running(sdata))
1748 			continue;
1749 		if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1750 			continue;
1751 		sdata->u.ibss.last_scan_completed = jiffies;
1752 	}
1753 	mutex_unlock(&local->iflist_mtx);
1754 }
1755 
1756 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1757 			struct cfg80211_ibss_params *params)
1758 {
1759 	u32 changed = 0;
1760 	u32 rate_flags;
1761 	struct ieee80211_supported_band *sband;
1762 	enum ieee80211_chanctx_mode chanmode;
1763 	struct ieee80211_local *local = sdata->local;
1764 	int radar_detect_width = 0;
1765 	int i;
1766 	int ret;
1767 
1768 	if (params->chandef.chan->freq_offset) {
1769 		/* this may work, but is untested */
1770 		return -EOPNOTSUPP;
1771 	}
1772 
1773 	ret = cfg80211_chandef_dfs_required(local->hw.wiphy,
1774 					    &params->chandef,
1775 					    sdata->wdev.iftype);
1776 	if (ret < 0)
1777 		return ret;
1778 
1779 	if (ret > 0) {
1780 		if (!params->userspace_handles_dfs)
1781 			return -EINVAL;
1782 		radar_detect_width = BIT(params->chandef.width);
1783 	}
1784 
1785 	chanmode = (params->channel_fixed && !ret) ?
1786 		IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE;
1787 
1788 	mutex_lock(&local->chanctx_mtx);
1789 	ret = ieee80211_check_combinations(sdata, &params->chandef, chanmode,
1790 					   radar_detect_width);
1791 	mutex_unlock(&local->chanctx_mtx);
1792 	if (ret < 0)
1793 		return ret;
1794 
1795 	if (params->bssid) {
1796 		memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1797 		sdata->u.ibss.fixed_bssid = true;
1798 	} else
1799 		sdata->u.ibss.fixed_bssid = false;
1800 
1801 	sdata->u.ibss.privacy = params->privacy;
1802 	sdata->u.ibss.control_port = params->control_port;
1803 	sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs;
1804 	sdata->u.ibss.basic_rates = params->basic_rates;
1805 	sdata->u.ibss.last_scan_completed = jiffies;
1806 
1807 	/* fix basic_rates if channel does not support these rates */
1808 	rate_flags = ieee80211_chandef_rate_flags(&params->chandef);
1809 	sband = local->hw.wiphy->bands[params->chandef.chan->band];
1810 	for (i = 0; i < sband->n_bitrates; i++) {
1811 		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
1812 			sdata->u.ibss.basic_rates &= ~BIT(i);
1813 	}
1814 	memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1815 	       sizeof(params->mcast_rate));
1816 
1817 	sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1818 
1819 	sdata->u.ibss.chandef = params->chandef;
1820 	sdata->u.ibss.fixed_channel = params->channel_fixed;
1821 
1822 	if (params->ie) {
1823 		sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1824 					   GFP_KERNEL);
1825 		if (sdata->u.ibss.ie)
1826 			sdata->u.ibss.ie_len = params->ie_len;
1827 	}
1828 
1829 	sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1830 	sdata->u.ibss.ibss_join_req = jiffies;
1831 
1832 	memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1833 	sdata->u.ibss.ssid_len = params->ssid_len;
1834 
1835 	memcpy(&sdata->u.ibss.ht_capa, &params->ht_capa,
1836 	       sizeof(sdata->u.ibss.ht_capa));
1837 	memcpy(&sdata->u.ibss.ht_capa_mask, &params->ht_capa_mask,
1838 	       sizeof(sdata->u.ibss.ht_capa_mask));
1839 
1840 	/*
1841 	 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1842 	 * reserved, but an HT STA shall protect HT transmissions as though
1843 	 * the HT Protection field were set to non-HT mixed mode.
1844 	 *
1845 	 * In an IBSS, the RIFS Mode field of the HT Operation element is
1846 	 * also reserved, but an HT STA shall operate as though this field
1847 	 * were set to 1.
1848 	 */
1849 
1850 	sdata->vif.bss_conf.ht_operation_mode |=
1851 		  IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1852 		| IEEE80211_HT_PARAM_RIFS_MODE;
1853 
1854 	changed |= BSS_CHANGED_HT | BSS_CHANGED_MCAST_RATE;
1855 	ieee80211_bss_info_change_notify(sdata, changed);
1856 
1857 	sdata->smps_mode = IEEE80211_SMPS_OFF;
1858 	sdata->needed_rx_chains = local->rx_chains;
1859 	sdata->control_port_over_nl80211 = params->control_port_over_nl80211;
1860 
1861 	ieee80211_queue_work(&local->hw, &sdata->work);
1862 
1863 	return 0;
1864 }
1865 
1866 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1867 {
1868 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1869 
1870 	ieee80211_ibss_disconnect(sdata);
1871 	ifibss->ssid_len = 0;
1872 	eth_zero_addr(ifibss->bssid);
1873 
1874 	/* remove beacon */
1875 	kfree(sdata->u.ibss.ie);
1876 
1877 	/* on the next join, re-program HT parameters */
1878 	memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
1879 	memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));
1880 
1881 	synchronize_rcu();
1882 
1883 	skb_queue_purge(&sdata->skb_queue);
1884 
1885 	del_timer_sync(&sdata->u.ibss.timer);
1886 
1887 	return 0;
1888 }
1889