xref: /kernel/linux/linux-5.10/net/wireless/chan.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * This file contains helper code to handle channel
4 * settings and keeping track of what is possible at
5 * any point in time.
6 *
7 * Copyright 2009	Johannes Berg <johannes@sipsolutions.net>
8 * Copyright 2013-2014  Intel Mobile Communications GmbH
9 * Copyright 2018-2020	Intel Corporation
10 */
11
12#include <linux/export.h>
13#include <linux/bitfield.h>
14#include <net/cfg80211.h>
15#include "core.h"
16#include "rdev-ops.h"
17
18static bool cfg80211_valid_60g_freq(u32 freq)
19{
20	return freq >= 58320 && freq <= 70200;
21}
22
23void cfg80211_chandef_create(struct cfg80211_chan_def *chandef,
24			     struct ieee80211_channel *chan,
25			     enum nl80211_channel_type chan_type)
26{
27	if (WARN_ON(!chan))
28		return;
29
30	chandef->chan = chan;
31	chandef->freq1_offset = chan->freq_offset;
32	chandef->center_freq2 = 0;
33	chandef->edmg.bw_config = 0;
34	chandef->edmg.channels = 0;
35
36	switch (chan_type) {
37	case NL80211_CHAN_NO_HT:
38		chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
39		chandef->center_freq1 = chan->center_freq;
40		break;
41	case NL80211_CHAN_HT20:
42		chandef->width = NL80211_CHAN_WIDTH_20;
43		chandef->center_freq1 = chan->center_freq;
44		break;
45	case NL80211_CHAN_HT40PLUS:
46		chandef->width = NL80211_CHAN_WIDTH_40;
47		chandef->center_freq1 = chan->center_freq + 10;
48		break;
49	case NL80211_CHAN_HT40MINUS:
50		chandef->width = NL80211_CHAN_WIDTH_40;
51		chandef->center_freq1 = chan->center_freq - 10;
52		break;
53	default:
54		WARN_ON(1);
55	}
56}
57EXPORT_SYMBOL(cfg80211_chandef_create);
58
59static bool cfg80211_edmg_chandef_valid(const struct cfg80211_chan_def *chandef)
60{
61	int max_contiguous = 0;
62	int num_of_enabled = 0;
63	int contiguous = 0;
64	int i;
65
66	if (!chandef->edmg.channels || !chandef->edmg.bw_config)
67		return false;
68
69	if (!cfg80211_valid_60g_freq(chandef->chan->center_freq))
70		return false;
71
72	for (i = 0; i < 6; i++) {
73		if (chandef->edmg.channels & BIT(i)) {
74			contiguous++;
75			num_of_enabled++;
76		} else {
77			contiguous = 0;
78		}
79
80		max_contiguous = max(contiguous, max_contiguous);
81	}
82	/* basic verification of edmg configuration according to
83	 * IEEE P802.11ay/D4.0 section 9.4.2.251
84	 */
85	/* check bw_config against contiguous edmg channels */
86	switch (chandef->edmg.bw_config) {
87	case IEEE80211_EDMG_BW_CONFIG_4:
88	case IEEE80211_EDMG_BW_CONFIG_8:
89	case IEEE80211_EDMG_BW_CONFIG_12:
90		if (max_contiguous < 1)
91			return false;
92		break;
93	case IEEE80211_EDMG_BW_CONFIG_5:
94	case IEEE80211_EDMG_BW_CONFIG_9:
95	case IEEE80211_EDMG_BW_CONFIG_13:
96		if (max_contiguous < 2)
97			return false;
98		break;
99	case IEEE80211_EDMG_BW_CONFIG_6:
100	case IEEE80211_EDMG_BW_CONFIG_10:
101	case IEEE80211_EDMG_BW_CONFIG_14:
102		if (max_contiguous < 3)
103			return false;
104		break;
105	case IEEE80211_EDMG_BW_CONFIG_7:
106	case IEEE80211_EDMG_BW_CONFIG_11:
107	case IEEE80211_EDMG_BW_CONFIG_15:
108		if (max_contiguous < 4)
109			return false;
110		break;
111
112	default:
113		return false;
114	}
115
116	/* check bw_config against aggregated (non contiguous) edmg channels */
117	switch (chandef->edmg.bw_config) {
118	case IEEE80211_EDMG_BW_CONFIG_4:
119	case IEEE80211_EDMG_BW_CONFIG_5:
120	case IEEE80211_EDMG_BW_CONFIG_6:
121	case IEEE80211_EDMG_BW_CONFIG_7:
122		break;
123	case IEEE80211_EDMG_BW_CONFIG_8:
124	case IEEE80211_EDMG_BW_CONFIG_9:
125	case IEEE80211_EDMG_BW_CONFIG_10:
126	case IEEE80211_EDMG_BW_CONFIG_11:
127		if (num_of_enabled < 2)
128			return false;
129		break;
130	case IEEE80211_EDMG_BW_CONFIG_12:
131	case IEEE80211_EDMG_BW_CONFIG_13:
132	case IEEE80211_EDMG_BW_CONFIG_14:
133	case IEEE80211_EDMG_BW_CONFIG_15:
134		if (num_of_enabled < 4 || max_contiguous < 2)
135			return false;
136		break;
137	default:
138		return false;
139	}
140
141	return true;
142}
143
144static int nl80211_chan_width_to_mhz(enum nl80211_chan_width chan_width)
145{
146	int mhz;
147
148	switch (chan_width) {
149	case NL80211_CHAN_WIDTH_1:
150		mhz = 1;
151		break;
152	case NL80211_CHAN_WIDTH_2:
153		mhz = 2;
154		break;
155	case NL80211_CHAN_WIDTH_4:
156		mhz = 4;
157		break;
158	case NL80211_CHAN_WIDTH_8:
159		mhz = 8;
160		break;
161	case NL80211_CHAN_WIDTH_16:
162		mhz = 16;
163		break;
164	case NL80211_CHAN_WIDTH_5:
165		mhz = 5;
166		break;
167	case NL80211_CHAN_WIDTH_10:
168		mhz = 10;
169		break;
170	case NL80211_CHAN_WIDTH_20:
171	case NL80211_CHAN_WIDTH_20_NOHT:
172		mhz = 20;
173		break;
174	case NL80211_CHAN_WIDTH_40:
175		mhz = 40;
176		break;
177	case NL80211_CHAN_WIDTH_80P80:
178	case NL80211_CHAN_WIDTH_80:
179		mhz = 80;
180		break;
181	case NL80211_CHAN_WIDTH_160:
182		mhz = 160;
183		break;
184	default:
185		WARN_ON_ONCE(1);
186		return -1;
187	}
188	return mhz;
189}
190
191static int cfg80211_chandef_get_width(const struct cfg80211_chan_def *c)
192{
193	return nl80211_chan_width_to_mhz(c->width);
194}
195
196bool cfg80211_chandef_valid(const struct cfg80211_chan_def *chandef)
197{
198	u32 control_freq, oper_freq;
199	int oper_width, control_width;
200
201	if (!chandef->chan)
202		return false;
203
204	if (chandef->freq1_offset >= 1000)
205		return false;
206
207	control_freq = chandef->chan->center_freq;
208
209	switch (chandef->width) {
210	case NL80211_CHAN_WIDTH_5:
211	case NL80211_CHAN_WIDTH_10:
212	case NL80211_CHAN_WIDTH_20:
213	case NL80211_CHAN_WIDTH_20_NOHT:
214		if (ieee80211_chandef_to_khz(chandef) !=
215		    ieee80211_channel_to_khz(chandef->chan))
216			return false;
217		if (chandef->center_freq2)
218			return false;
219		break;
220	case NL80211_CHAN_WIDTH_1:
221	case NL80211_CHAN_WIDTH_2:
222	case NL80211_CHAN_WIDTH_4:
223	case NL80211_CHAN_WIDTH_8:
224	case NL80211_CHAN_WIDTH_16:
225		if (chandef->chan->band != NL80211_BAND_S1GHZ)
226			return false;
227
228		control_freq = ieee80211_channel_to_khz(chandef->chan);
229		oper_freq = ieee80211_chandef_to_khz(chandef);
230		control_width = nl80211_chan_width_to_mhz(
231					ieee80211_s1g_channel_width(
232								chandef->chan));
233		oper_width = cfg80211_chandef_get_width(chandef);
234
235		if (oper_width < 0 || control_width < 0)
236			return false;
237		if (chandef->center_freq2)
238			return false;
239
240		if (control_freq + MHZ_TO_KHZ(control_width) / 2 >
241		    oper_freq + MHZ_TO_KHZ(oper_width) / 2)
242			return false;
243
244		if (control_freq - MHZ_TO_KHZ(control_width) / 2 <
245		    oper_freq - MHZ_TO_KHZ(oper_width) / 2)
246			return false;
247		break;
248	case NL80211_CHAN_WIDTH_40:
249		if (chandef->center_freq1 != control_freq + 10 &&
250		    chandef->center_freq1 != control_freq - 10)
251			return false;
252		if (chandef->center_freq2)
253			return false;
254		break;
255	case NL80211_CHAN_WIDTH_80P80:
256		if (chandef->center_freq1 != control_freq + 30 &&
257		    chandef->center_freq1 != control_freq + 10 &&
258		    chandef->center_freq1 != control_freq - 10 &&
259		    chandef->center_freq1 != control_freq - 30)
260			return false;
261		if (!chandef->center_freq2)
262			return false;
263		/* adjacent is not allowed -- that's a 160 MHz channel */
264		if (chandef->center_freq1 - chandef->center_freq2 == 80 ||
265		    chandef->center_freq2 - chandef->center_freq1 == 80)
266			return false;
267		break;
268	case NL80211_CHAN_WIDTH_80:
269		if (chandef->center_freq1 != control_freq + 30 &&
270		    chandef->center_freq1 != control_freq + 10 &&
271		    chandef->center_freq1 != control_freq - 10 &&
272		    chandef->center_freq1 != control_freq - 30)
273			return false;
274		if (chandef->center_freq2)
275			return false;
276		break;
277	case NL80211_CHAN_WIDTH_160:
278		if (chandef->center_freq1 != control_freq + 70 &&
279		    chandef->center_freq1 != control_freq + 50 &&
280		    chandef->center_freq1 != control_freq + 30 &&
281		    chandef->center_freq1 != control_freq + 10 &&
282		    chandef->center_freq1 != control_freq - 10 &&
283		    chandef->center_freq1 != control_freq - 30 &&
284		    chandef->center_freq1 != control_freq - 50 &&
285		    chandef->center_freq1 != control_freq - 70)
286			return false;
287		if (chandef->center_freq2)
288			return false;
289		break;
290	default:
291		return false;
292	}
293
294	/* channel 14 is only for IEEE 802.11b */
295	if (chandef->center_freq1 == 2484 &&
296	    chandef->width != NL80211_CHAN_WIDTH_20_NOHT)
297		return false;
298
299	if (cfg80211_chandef_is_edmg(chandef) &&
300	    !cfg80211_edmg_chandef_valid(chandef))
301		return false;
302
303	return true;
304}
305EXPORT_SYMBOL(cfg80211_chandef_valid);
306
307static void chandef_primary_freqs(const struct cfg80211_chan_def *c,
308				  u32 *pri40, u32 *pri80)
309{
310	int tmp;
311
312	switch (c->width) {
313	case NL80211_CHAN_WIDTH_40:
314		*pri40 = c->center_freq1;
315		*pri80 = 0;
316		break;
317	case NL80211_CHAN_WIDTH_80:
318	case NL80211_CHAN_WIDTH_80P80:
319		*pri80 = c->center_freq1;
320		/* n_P20 */
321		tmp = (30 + c->chan->center_freq - c->center_freq1)/20;
322		/* n_P40 */
323		tmp /= 2;
324		/* freq_P40 */
325		*pri40 = c->center_freq1 - 20 + 40 * tmp;
326		break;
327	case NL80211_CHAN_WIDTH_160:
328		/* n_P20 */
329		tmp = (70 + c->chan->center_freq - c->center_freq1)/20;
330		/* n_P40 */
331		tmp /= 2;
332		/* freq_P40 */
333		*pri40 = c->center_freq1 - 60 + 40 * tmp;
334		/* n_P80 */
335		tmp /= 2;
336		*pri80 = c->center_freq1 - 40 + 80 * tmp;
337		break;
338	default:
339		WARN_ON_ONCE(1);
340	}
341}
342
343const struct cfg80211_chan_def *
344cfg80211_chandef_compatible(const struct cfg80211_chan_def *c1,
345			    const struct cfg80211_chan_def *c2)
346{
347	u32 c1_pri40, c1_pri80, c2_pri40, c2_pri80;
348
349	/* If they are identical, return */
350	if (cfg80211_chandef_identical(c1, c2))
351		return c1;
352
353	/* otherwise, must have same control channel */
354	if (c1->chan != c2->chan)
355		return NULL;
356
357	/*
358	 * If they have the same width, but aren't identical,
359	 * then they can't be compatible.
360	 */
361	if (c1->width == c2->width)
362		return NULL;
363
364	/*
365	 * can't be compatible if one of them is 5 or 10 MHz,
366	 * but they don't have the same width.
367	 */
368	if (c1->width == NL80211_CHAN_WIDTH_5 ||
369	    c1->width == NL80211_CHAN_WIDTH_10 ||
370	    c2->width == NL80211_CHAN_WIDTH_5 ||
371	    c2->width == NL80211_CHAN_WIDTH_10)
372		return NULL;
373
374	if (c1->width == NL80211_CHAN_WIDTH_20_NOHT ||
375	    c1->width == NL80211_CHAN_WIDTH_20)
376		return c2;
377
378	if (c2->width == NL80211_CHAN_WIDTH_20_NOHT ||
379	    c2->width == NL80211_CHAN_WIDTH_20)
380		return c1;
381
382	chandef_primary_freqs(c1, &c1_pri40, &c1_pri80);
383	chandef_primary_freqs(c2, &c2_pri40, &c2_pri80);
384
385	if (c1_pri40 != c2_pri40)
386		return NULL;
387
388	WARN_ON(!c1_pri80 && !c2_pri80);
389	if (c1_pri80 && c2_pri80 && c1_pri80 != c2_pri80)
390		return NULL;
391
392	if (c1->width > c2->width)
393		return c1;
394	return c2;
395}
396EXPORT_SYMBOL(cfg80211_chandef_compatible);
397
398static void cfg80211_set_chans_dfs_state(struct wiphy *wiphy, u32 center_freq,
399					 u32 bandwidth,
400					 enum nl80211_dfs_state dfs_state)
401{
402	struct ieee80211_channel *c;
403	u32 freq;
404
405	for (freq = center_freq - bandwidth/2 + 10;
406	     freq <= center_freq + bandwidth/2 - 10;
407	     freq += 20) {
408		c = ieee80211_get_channel(wiphy, freq);
409		if (!c || !(c->flags & IEEE80211_CHAN_RADAR))
410			continue;
411
412		c->dfs_state = dfs_state;
413		c->dfs_state_entered = jiffies;
414	}
415}
416
417void cfg80211_set_dfs_state(struct wiphy *wiphy,
418			    const struct cfg80211_chan_def *chandef,
419			    enum nl80211_dfs_state dfs_state)
420{
421	int width;
422
423	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
424		return;
425
426	width = cfg80211_chandef_get_width(chandef);
427	if (width < 0)
428		return;
429
430	cfg80211_set_chans_dfs_state(wiphy, chandef->center_freq1,
431				     width, dfs_state);
432
433	if (!chandef->center_freq2)
434		return;
435	cfg80211_set_chans_dfs_state(wiphy, chandef->center_freq2,
436				     width, dfs_state);
437}
438
439static u32 cfg80211_get_start_freq(u32 center_freq,
440				   u32 bandwidth)
441{
442	u32 start_freq;
443
444	bandwidth = MHZ_TO_KHZ(bandwidth);
445	if (bandwidth <= MHZ_TO_KHZ(20))
446		start_freq = center_freq;
447	else
448		start_freq = center_freq - bandwidth / 2 + MHZ_TO_KHZ(10);
449
450	return start_freq;
451}
452
453static u32 cfg80211_get_end_freq(u32 center_freq,
454				 u32 bandwidth)
455{
456	u32 end_freq;
457
458	bandwidth = MHZ_TO_KHZ(bandwidth);
459	if (bandwidth <= MHZ_TO_KHZ(20))
460		end_freq = center_freq;
461	else
462		end_freq = center_freq + bandwidth / 2 - MHZ_TO_KHZ(10);
463
464	return end_freq;
465}
466
467static int cfg80211_get_chans_dfs_required(struct wiphy *wiphy,
468					    u32 center_freq,
469					    u32 bandwidth)
470{
471	struct ieee80211_channel *c;
472	u32 freq, start_freq, end_freq;
473
474	start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
475	end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
476
477	for (freq = start_freq; freq <= end_freq; freq += MHZ_TO_KHZ(20)) {
478		c = ieee80211_get_channel_khz(wiphy, freq);
479		if (!c)
480			return -EINVAL;
481
482		if (c->flags & IEEE80211_CHAN_RADAR)
483			return 1;
484	}
485	return 0;
486}
487
488
489int cfg80211_chandef_dfs_required(struct wiphy *wiphy,
490				  const struct cfg80211_chan_def *chandef,
491				  enum nl80211_iftype iftype)
492{
493	int width;
494	int ret;
495
496	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
497		return -EINVAL;
498
499	switch (iftype) {
500	case NL80211_IFTYPE_ADHOC:
501	case NL80211_IFTYPE_AP:
502	case NL80211_IFTYPE_P2P_GO:
503	case NL80211_IFTYPE_MESH_POINT:
504		width = cfg80211_chandef_get_width(chandef);
505		if (width < 0)
506			return -EINVAL;
507
508		ret = cfg80211_get_chans_dfs_required(wiphy,
509					ieee80211_chandef_to_khz(chandef),
510					width);
511		if (ret < 0)
512			return ret;
513		else if (ret > 0)
514			return BIT(chandef->width);
515
516		if (!chandef->center_freq2)
517			return 0;
518
519		ret = cfg80211_get_chans_dfs_required(wiphy,
520					MHZ_TO_KHZ(chandef->center_freq2),
521					width);
522		if (ret < 0)
523			return ret;
524		else if (ret > 0)
525			return BIT(chandef->width);
526
527		break;
528	case NL80211_IFTYPE_STATION:
529	case NL80211_IFTYPE_OCB:
530	case NL80211_IFTYPE_P2P_CLIENT:
531	case NL80211_IFTYPE_MONITOR:
532	case NL80211_IFTYPE_AP_VLAN:
533	case NL80211_IFTYPE_WDS:
534	case NL80211_IFTYPE_P2P_DEVICE:
535	case NL80211_IFTYPE_NAN:
536		break;
537	case NL80211_IFTYPE_UNSPECIFIED:
538	case NUM_NL80211_IFTYPES:
539		WARN_ON(1);
540	}
541
542	return 0;
543}
544EXPORT_SYMBOL(cfg80211_chandef_dfs_required);
545
546static int cfg80211_get_chans_dfs_usable(struct wiphy *wiphy,
547					 u32 center_freq,
548					 u32 bandwidth)
549{
550	struct ieee80211_channel *c;
551	u32 freq, start_freq, end_freq;
552	int count = 0;
553
554	start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
555	end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
556
557	/*
558	 * Check entire range of channels for the bandwidth.
559	 * Check all channels are DFS channels (DFS_USABLE or
560	 * DFS_AVAILABLE). Return number of usable channels
561	 * (require CAC). Allow DFS and non-DFS channel mix.
562	 */
563	for (freq = start_freq; freq <= end_freq; freq += MHZ_TO_KHZ(20)) {
564		c = ieee80211_get_channel_khz(wiphy, freq);
565		if (!c)
566			return -EINVAL;
567
568		if (c->flags & IEEE80211_CHAN_DISABLED)
569			return -EINVAL;
570
571		if (c->flags & IEEE80211_CHAN_RADAR) {
572			if (c->dfs_state == NL80211_DFS_UNAVAILABLE)
573				return -EINVAL;
574
575			if (c->dfs_state == NL80211_DFS_USABLE)
576				count++;
577		}
578	}
579
580	return count;
581}
582
583bool cfg80211_chandef_dfs_usable(struct wiphy *wiphy,
584				 const struct cfg80211_chan_def *chandef)
585{
586	int width;
587	int r1, r2 = 0;
588
589	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
590		return false;
591
592	width = cfg80211_chandef_get_width(chandef);
593	if (width < 0)
594		return false;
595
596	r1 = cfg80211_get_chans_dfs_usable(wiphy,
597					   MHZ_TO_KHZ(chandef->center_freq1),
598					   width);
599
600	if (r1 < 0)
601		return false;
602
603	switch (chandef->width) {
604	case NL80211_CHAN_WIDTH_80P80:
605		WARN_ON(!chandef->center_freq2);
606		r2 = cfg80211_get_chans_dfs_usable(wiphy,
607					MHZ_TO_KHZ(chandef->center_freq2),
608					width);
609		if (r2 < 0)
610			return false;
611		break;
612	default:
613		WARN_ON(chandef->center_freq2);
614		break;
615	}
616
617	return (r1 + r2 > 0);
618}
619
620/*
621 * Checks if center frequency of chan falls with in the bandwidth
622 * range of chandef.
623 */
624bool cfg80211_is_sub_chan(struct cfg80211_chan_def *chandef,
625			  struct ieee80211_channel *chan)
626{
627	int width;
628	u32 freq;
629
630	if (chandef->chan->center_freq == chan->center_freq)
631		return true;
632
633	width = cfg80211_chandef_get_width(chandef);
634	if (width <= 20)
635		return false;
636
637	for (freq = chandef->center_freq1 - width / 2 + 10;
638	     freq <= chandef->center_freq1 + width / 2 - 10; freq += 20) {
639		if (chan->center_freq == freq)
640			return true;
641	}
642
643	if (!chandef->center_freq2)
644		return false;
645
646	for (freq = chandef->center_freq2 - width / 2 + 10;
647	     freq <= chandef->center_freq2 + width / 2 - 10; freq += 20) {
648		if (chan->center_freq == freq)
649			return true;
650	}
651
652	return false;
653}
654
655bool cfg80211_beaconing_iface_active(struct wireless_dev *wdev)
656{
657	bool active = false;
658
659	ASSERT_WDEV_LOCK(wdev);
660
661	if (!wdev->chandef.chan)
662		return false;
663
664	switch (wdev->iftype) {
665	case NL80211_IFTYPE_AP:
666	case NL80211_IFTYPE_P2P_GO:
667		active = wdev->beacon_interval != 0;
668		break;
669	case NL80211_IFTYPE_ADHOC:
670		active = wdev->ssid_len != 0;
671		break;
672	case NL80211_IFTYPE_MESH_POINT:
673		active = wdev->mesh_id_len != 0;
674		break;
675	case NL80211_IFTYPE_STATION:
676	case NL80211_IFTYPE_OCB:
677	case NL80211_IFTYPE_P2P_CLIENT:
678	case NL80211_IFTYPE_MONITOR:
679	case NL80211_IFTYPE_AP_VLAN:
680	case NL80211_IFTYPE_WDS:
681	case NL80211_IFTYPE_P2P_DEVICE:
682	/* Can NAN type be considered as beaconing interface? */
683	case NL80211_IFTYPE_NAN:
684		break;
685	case NL80211_IFTYPE_UNSPECIFIED:
686	case NUM_NL80211_IFTYPES:
687		WARN_ON(1);
688	}
689
690	return active;
691}
692
693static bool cfg80211_is_wiphy_oper_chan(struct wiphy *wiphy,
694					struct ieee80211_channel *chan)
695{
696	struct wireless_dev *wdev;
697
698	list_for_each_entry(wdev, &wiphy->wdev_list, list) {
699		wdev_lock(wdev);
700		if (!cfg80211_beaconing_iface_active(wdev)) {
701			wdev_unlock(wdev);
702			continue;
703		}
704
705		if (cfg80211_is_sub_chan(&wdev->chandef, chan)) {
706			wdev_unlock(wdev);
707			return true;
708		}
709		wdev_unlock(wdev);
710	}
711
712	return false;
713}
714
715bool cfg80211_any_wiphy_oper_chan(struct wiphy *wiphy,
716				  struct ieee80211_channel *chan)
717{
718	struct cfg80211_registered_device *rdev;
719
720	ASSERT_RTNL();
721
722	if (!(chan->flags & IEEE80211_CHAN_RADAR))
723		return false;
724
725	list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
726		if (!reg_dfs_domain_same(wiphy, &rdev->wiphy))
727			continue;
728
729		if (cfg80211_is_wiphy_oper_chan(&rdev->wiphy, chan))
730			return true;
731	}
732
733	return false;
734}
735
736static bool cfg80211_get_chans_dfs_available(struct wiphy *wiphy,
737					     u32 center_freq,
738					     u32 bandwidth)
739{
740	struct ieee80211_channel *c;
741	u32 freq, start_freq, end_freq;
742	bool dfs_offload;
743
744	dfs_offload = wiphy_ext_feature_isset(wiphy,
745					      NL80211_EXT_FEATURE_DFS_OFFLOAD);
746
747	start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
748	end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
749
750	/*
751	 * Check entire range of channels for the bandwidth.
752	 * If any channel in between is disabled or has not
753	 * had gone through CAC return false
754	 */
755	for (freq = start_freq; freq <= end_freq; freq += MHZ_TO_KHZ(20)) {
756		c = ieee80211_get_channel_khz(wiphy, freq);
757		if (!c)
758			return false;
759
760		if (c->flags & IEEE80211_CHAN_DISABLED)
761			return false;
762
763		if ((c->flags & IEEE80211_CHAN_RADAR) &&
764		    (c->dfs_state != NL80211_DFS_AVAILABLE) &&
765		    !(c->dfs_state == NL80211_DFS_USABLE && dfs_offload))
766			return false;
767	}
768
769	return true;
770}
771
772static bool cfg80211_chandef_dfs_available(struct wiphy *wiphy,
773				const struct cfg80211_chan_def *chandef)
774{
775	int width;
776	int r;
777
778	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
779		return false;
780
781	width = cfg80211_chandef_get_width(chandef);
782	if (width < 0)
783		return false;
784
785	r = cfg80211_get_chans_dfs_available(wiphy,
786					     MHZ_TO_KHZ(chandef->center_freq1),
787					     width);
788
789	/* If any of channels unavailable for cf1 just return */
790	if (!r)
791		return r;
792
793	switch (chandef->width) {
794	case NL80211_CHAN_WIDTH_80P80:
795		WARN_ON(!chandef->center_freq2);
796		r = cfg80211_get_chans_dfs_available(wiphy,
797					MHZ_TO_KHZ(chandef->center_freq2),
798					width);
799		break;
800	default:
801		WARN_ON(chandef->center_freq2);
802		break;
803	}
804
805	return r;
806}
807
808static unsigned int cfg80211_get_chans_dfs_cac_time(struct wiphy *wiphy,
809						    u32 center_freq,
810						    u32 bandwidth)
811{
812	struct ieee80211_channel *c;
813	u32 start_freq, end_freq, freq;
814	unsigned int dfs_cac_ms = 0;
815
816	start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
817	end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
818
819	for (freq = start_freq; freq <= end_freq; freq += MHZ_TO_KHZ(20)) {
820		c = ieee80211_get_channel_khz(wiphy, freq);
821		if (!c)
822			return 0;
823
824		if (c->flags & IEEE80211_CHAN_DISABLED)
825			return 0;
826
827		if (!(c->flags & IEEE80211_CHAN_RADAR))
828			continue;
829
830		if (c->dfs_cac_ms > dfs_cac_ms)
831			dfs_cac_ms = c->dfs_cac_ms;
832	}
833
834	return dfs_cac_ms;
835}
836
837unsigned int
838cfg80211_chandef_dfs_cac_time(struct wiphy *wiphy,
839			      const struct cfg80211_chan_def *chandef)
840{
841	int width;
842	unsigned int t1 = 0, t2 = 0;
843
844	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
845		return 0;
846
847	width = cfg80211_chandef_get_width(chandef);
848	if (width < 0)
849		return 0;
850
851	t1 = cfg80211_get_chans_dfs_cac_time(wiphy,
852					     MHZ_TO_KHZ(chandef->center_freq1),
853					     width);
854
855	if (!chandef->center_freq2)
856		return t1;
857
858	t2 = cfg80211_get_chans_dfs_cac_time(wiphy,
859					     MHZ_TO_KHZ(chandef->center_freq2),
860					     width);
861
862	return max(t1, t2);
863}
864
865static bool cfg80211_secondary_chans_ok(struct wiphy *wiphy,
866					u32 center_freq, u32 bandwidth,
867					u32 prohibited_flags)
868{
869	struct ieee80211_channel *c;
870	u32 freq, start_freq, end_freq;
871
872	start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
873	end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
874
875	for (freq = start_freq; freq <= end_freq; freq += MHZ_TO_KHZ(20)) {
876		c = ieee80211_get_channel_khz(wiphy, freq);
877		if (!c || c->flags & prohibited_flags)
878			return false;
879	}
880
881	return true;
882}
883
884/* check if the operating channels are valid and supported */
885static bool cfg80211_edmg_usable(struct wiphy *wiphy, u8 edmg_channels,
886				 enum ieee80211_edmg_bw_config edmg_bw_config,
887				 int primary_channel,
888				 struct ieee80211_edmg *edmg_cap)
889{
890	struct ieee80211_channel *chan;
891	int i, freq;
892	int channels_counter = 0;
893
894	if (!edmg_channels && !edmg_bw_config)
895		return true;
896
897	if ((!edmg_channels && edmg_bw_config) ||
898	    (edmg_channels && !edmg_bw_config))
899		return false;
900
901	if (!(edmg_channels & BIT(primary_channel - 1)))
902		return false;
903
904	/* 60GHz channels 1..6 */
905	for (i = 0; i < 6; i++) {
906		if (!(edmg_channels & BIT(i)))
907			continue;
908
909		if (!(edmg_cap->channels & BIT(i)))
910			return false;
911
912		channels_counter++;
913
914		freq = ieee80211_channel_to_frequency(i + 1,
915						      NL80211_BAND_60GHZ);
916		chan = ieee80211_get_channel(wiphy, freq);
917		if (!chan || chan->flags & IEEE80211_CHAN_DISABLED)
918			return false;
919	}
920
921	/* IEEE802.11 allows max 4 channels */
922	if (channels_counter > 4)
923		return false;
924
925	/* check bw_config is a subset of what driver supports
926	 * (see IEEE P802.11ay/D4.0 section 9.4.2.251, Table 13)
927	 */
928	if ((edmg_bw_config % 4) > (edmg_cap->bw_config % 4))
929		return false;
930
931	if (edmg_bw_config > edmg_cap->bw_config)
932		return false;
933
934	return true;
935}
936
937bool cfg80211_chandef_usable(struct wiphy *wiphy,
938			     const struct cfg80211_chan_def *chandef,
939			     u32 prohibited_flags)
940{
941	struct ieee80211_sta_ht_cap *ht_cap;
942	struct ieee80211_sta_vht_cap *vht_cap;
943	struct ieee80211_edmg *edmg_cap;
944	u32 width, control_freq, cap;
945	bool support_80_80 = false;
946
947	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
948		return false;
949
950	ht_cap = &wiphy->bands[chandef->chan->band]->ht_cap;
951	vht_cap = &wiphy->bands[chandef->chan->band]->vht_cap;
952	edmg_cap = &wiphy->bands[chandef->chan->band]->edmg_cap;
953
954	if (edmg_cap->channels &&
955	    !cfg80211_edmg_usable(wiphy,
956				  chandef->edmg.channels,
957				  chandef->edmg.bw_config,
958				  chandef->chan->hw_value,
959				  edmg_cap))
960		return false;
961
962	control_freq = chandef->chan->center_freq;
963
964	switch (chandef->width) {
965	case NL80211_CHAN_WIDTH_1:
966		width = 1;
967		break;
968	case NL80211_CHAN_WIDTH_2:
969		width = 2;
970		break;
971	case NL80211_CHAN_WIDTH_4:
972		width = 4;
973		break;
974	case NL80211_CHAN_WIDTH_8:
975		width = 8;
976		break;
977	case NL80211_CHAN_WIDTH_16:
978		width = 16;
979		break;
980	case NL80211_CHAN_WIDTH_5:
981		width = 5;
982		break;
983	case NL80211_CHAN_WIDTH_10:
984		prohibited_flags |= IEEE80211_CHAN_NO_10MHZ;
985		width = 10;
986		break;
987	case NL80211_CHAN_WIDTH_20:
988		if (!ht_cap->ht_supported &&
989		    chandef->chan->band != NL80211_BAND_6GHZ)
990			return false;
991		fallthrough;
992	case NL80211_CHAN_WIDTH_20_NOHT:
993		prohibited_flags |= IEEE80211_CHAN_NO_20MHZ;
994		width = 20;
995		break;
996	case NL80211_CHAN_WIDTH_40:
997		width = 40;
998		if (chandef->chan->band == NL80211_BAND_6GHZ)
999			break;
1000		if (!ht_cap->ht_supported)
1001			return false;
1002		if (!(ht_cap->cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) ||
1003		    ht_cap->cap & IEEE80211_HT_CAP_40MHZ_INTOLERANT)
1004			return false;
1005		if (chandef->center_freq1 < control_freq &&
1006		    chandef->chan->flags & IEEE80211_CHAN_NO_HT40MINUS)
1007			return false;
1008		if (chandef->center_freq1 > control_freq &&
1009		    chandef->chan->flags & IEEE80211_CHAN_NO_HT40PLUS)
1010			return false;
1011		break;
1012	case NL80211_CHAN_WIDTH_80P80:
1013		cap = vht_cap->cap;
1014		support_80_80 =
1015			(cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ) ||
1016			(cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ &&
1017			 cap & IEEE80211_VHT_CAP_EXT_NSS_BW_MASK) ||
1018			u32_get_bits(cap, IEEE80211_VHT_CAP_EXT_NSS_BW_MASK) > 1;
1019		if (chandef->chan->band != NL80211_BAND_6GHZ && !support_80_80)
1020			return false;
1021		fallthrough;
1022	case NL80211_CHAN_WIDTH_80:
1023		prohibited_flags |= IEEE80211_CHAN_NO_80MHZ;
1024		width = 80;
1025		if (chandef->chan->band == NL80211_BAND_6GHZ)
1026			break;
1027		if (!vht_cap->vht_supported)
1028			return false;
1029		break;
1030	case NL80211_CHAN_WIDTH_160:
1031		prohibited_flags |= IEEE80211_CHAN_NO_160MHZ;
1032		width = 160;
1033		if (chandef->chan->band == NL80211_BAND_6GHZ)
1034			break;
1035		if (!vht_cap->vht_supported)
1036			return false;
1037		cap = vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
1038		if (cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ &&
1039		    cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ &&
1040		    !(vht_cap->cap & IEEE80211_VHT_CAP_EXT_NSS_BW_MASK))
1041			return false;
1042		break;
1043	default:
1044		WARN_ON_ONCE(1);
1045		return false;
1046	}
1047
1048	/*
1049	 * TODO: What if there are only certain 80/160/80+80 MHz channels
1050	 *	 allowed by the driver, or only certain combinations?
1051	 *	 For 40 MHz the driver can set the NO_HT40 flags, but for
1052	 *	 80/160 MHz and in particular 80+80 MHz this isn't really
1053	 *	 feasible and we only have NO_80MHZ/NO_160MHZ so far but
1054	 *	 no way to cover 80+80 MHz or more complex restrictions.
1055	 *	 Note that such restrictions also need to be advertised to
1056	 *	 userspace, for example for P2P channel selection.
1057	 */
1058
1059	if (width > 20)
1060		prohibited_flags |= IEEE80211_CHAN_NO_OFDM;
1061
1062	/* 5 and 10 MHz are only defined for the OFDM PHY */
1063	if (width < 20)
1064		prohibited_flags |= IEEE80211_CHAN_NO_OFDM;
1065
1066
1067	if (!cfg80211_secondary_chans_ok(wiphy,
1068					 ieee80211_chandef_to_khz(chandef),
1069					 width, prohibited_flags))
1070		return false;
1071
1072	if (!chandef->center_freq2)
1073		return true;
1074	return cfg80211_secondary_chans_ok(wiphy,
1075					   MHZ_TO_KHZ(chandef->center_freq2),
1076					   width, prohibited_flags);
1077}
1078EXPORT_SYMBOL(cfg80211_chandef_usable);
1079
1080/*
1081 * Check if the channel can be used under permissive conditions mandated by
1082 * some regulatory bodies, i.e., the channel is marked with
1083 * IEEE80211_CHAN_IR_CONCURRENT and there is an additional station interface
1084 * associated to an AP on the same channel or on the same UNII band
1085 * (assuming that the AP is an authorized master).
1086 * In addition allow operation on a channel on which indoor operation is
1087 * allowed, iff we are currently operating in an indoor environment.
1088 */
1089static bool cfg80211_ir_permissive_chan(struct wiphy *wiphy,
1090					enum nl80211_iftype iftype,
1091					struct ieee80211_channel *chan)
1092{
1093	struct wireless_dev *wdev;
1094	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1095
1096	ASSERT_RTNL();
1097
1098	if (!IS_ENABLED(CONFIG_CFG80211_REG_RELAX_NO_IR) ||
1099	    !(wiphy->regulatory_flags & REGULATORY_ENABLE_RELAX_NO_IR))
1100		return false;
1101
1102	/* only valid for GO and TDLS off-channel (station/p2p-CL) */
1103	if (iftype != NL80211_IFTYPE_P2P_GO &&
1104	    iftype != NL80211_IFTYPE_STATION &&
1105	    iftype != NL80211_IFTYPE_P2P_CLIENT)
1106		return false;
1107
1108	if (regulatory_indoor_allowed() &&
1109	    (chan->flags & IEEE80211_CHAN_INDOOR_ONLY))
1110		return true;
1111
1112	if (!(chan->flags & IEEE80211_CHAN_IR_CONCURRENT))
1113		return false;
1114
1115	/*
1116	 * Generally, it is possible to rely on another device/driver to allow
1117	 * the IR concurrent relaxation, however, since the device can further
1118	 * enforce the relaxation (by doing a similar verifications as this),
1119	 * and thus fail the GO instantiation, consider only the interfaces of
1120	 * the current registered device.
1121	 */
1122	list_for_each_entry(wdev, &rdev->wiphy.wdev_list, list) {
1123		struct ieee80211_channel *other_chan = NULL;
1124		int r1, r2;
1125
1126		wdev_lock(wdev);
1127		if (wdev->iftype == NL80211_IFTYPE_STATION &&
1128		    wdev->current_bss)
1129			other_chan = wdev->current_bss->pub.channel;
1130
1131		/*
1132		 * If a GO already operates on the same GO_CONCURRENT channel,
1133		 * this one (maybe the same one) can beacon as well. We allow
1134		 * the operation even if the station we relied on with
1135		 * GO_CONCURRENT is disconnected now. But then we must make sure
1136		 * we're not outdoor on an indoor-only channel.
1137		 */
1138		if (iftype == NL80211_IFTYPE_P2P_GO &&
1139		    wdev->iftype == NL80211_IFTYPE_P2P_GO &&
1140		    wdev->beacon_interval &&
1141		    !(chan->flags & IEEE80211_CHAN_INDOOR_ONLY))
1142			other_chan = wdev->chandef.chan;
1143		wdev_unlock(wdev);
1144
1145		if (!other_chan)
1146			continue;
1147
1148		if (chan == other_chan)
1149			return true;
1150
1151		if (chan->band != NL80211_BAND_5GHZ &&
1152		    chan->band != NL80211_BAND_6GHZ)
1153			continue;
1154
1155		r1 = cfg80211_get_unii(chan->center_freq);
1156		r2 = cfg80211_get_unii(other_chan->center_freq);
1157
1158		if (r1 != -EINVAL && r1 == r2) {
1159			/*
1160			 * At some locations channels 149-165 are considered a
1161			 * bundle, but at other locations, e.g., Indonesia,
1162			 * channels 149-161 are considered a bundle while
1163			 * channel 165 is left out and considered to be in a
1164			 * different bundle. Thus, in case that there is a
1165			 * station interface connected to an AP on channel 165,
1166			 * it is assumed that channels 149-161 are allowed for
1167			 * GO operations. However, having a station interface
1168			 * connected to an AP on channels 149-161, does not
1169			 * allow GO operation on channel 165.
1170			 */
1171			if (chan->center_freq == 5825 &&
1172			    other_chan->center_freq != 5825)
1173				continue;
1174			return true;
1175		}
1176	}
1177
1178	return false;
1179}
1180
1181static bool _cfg80211_reg_can_beacon(struct wiphy *wiphy,
1182				     struct cfg80211_chan_def *chandef,
1183				     enum nl80211_iftype iftype,
1184				     bool check_no_ir)
1185{
1186	bool res;
1187	u32 prohibited_flags = IEEE80211_CHAN_DISABLED |
1188			       IEEE80211_CHAN_RADAR;
1189
1190	trace_cfg80211_reg_can_beacon(wiphy, chandef, iftype, check_no_ir);
1191
1192	if (check_no_ir)
1193		prohibited_flags |= IEEE80211_CHAN_NO_IR;
1194
1195	if (cfg80211_chandef_dfs_required(wiphy, chandef, iftype) > 0 &&
1196	    cfg80211_chandef_dfs_available(wiphy, chandef)) {
1197		/* We can skip IEEE80211_CHAN_NO_IR if chandef dfs available */
1198		prohibited_flags = IEEE80211_CHAN_DISABLED;
1199	}
1200
1201	res = cfg80211_chandef_usable(wiphy, chandef, prohibited_flags);
1202
1203	trace_cfg80211_return_bool(res);
1204	return res;
1205}
1206
1207bool cfg80211_reg_can_beacon(struct wiphy *wiphy,
1208			     struct cfg80211_chan_def *chandef,
1209			     enum nl80211_iftype iftype)
1210{
1211	return _cfg80211_reg_can_beacon(wiphy, chandef, iftype, true);
1212}
1213EXPORT_SYMBOL(cfg80211_reg_can_beacon);
1214
1215bool cfg80211_reg_can_beacon_relax(struct wiphy *wiphy,
1216				   struct cfg80211_chan_def *chandef,
1217				   enum nl80211_iftype iftype)
1218{
1219	bool check_no_ir;
1220
1221	ASSERT_RTNL();
1222
1223	/*
1224	 * Under certain conditions suggested by some regulatory bodies a
1225	 * GO/STA can IR on channels marked with IEEE80211_NO_IR. Set this flag
1226	 * only if such relaxations are not enabled and the conditions are not
1227	 * met.
1228	 */
1229	check_no_ir = !cfg80211_ir_permissive_chan(wiphy, iftype,
1230						   chandef->chan);
1231
1232	return _cfg80211_reg_can_beacon(wiphy, chandef, iftype, check_no_ir);
1233}
1234EXPORT_SYMBOL(cfg80211_reg_can_beacon_relax);
1235
1236int cfg80211_set_monitor_channel(struct cfg80211_registered_device *rdev,
1237				 struct cfg80211_chan_def *chandef)
1238{
1239	if (!rdev->ops->set_monitor_channel)
1240		return -EOPNOTSUPP;
1241	if (!cfg80211_has_monitors_only(rdev))
1242		return -EBUSY;
1243
1244	return rdev_set_monitor_channel(rdev, chandef);
1245}
1246
1247void
1248cfg80211_get_chan_state(struct wireless_dev *wdev,
1249		        struct ieee80211_channel **chan,
1250		        enum cfg80211_chan_mode *chanmode,
1251		        u8 *radar_detect)
1252{
1253	int ret;
1254
1255	*chan = NULL;
1256	*chanmode = CHAN_MODE_UNDEFINED;
1257
1258	ASSERT_WDEV_LOCK(wdev);
1259
1260	if (wdev->netdev && !netif_running(wdev->netdev))
1261		return;
1262
1263	switch (wdev->iftype) {
1264	case NL80211_IFTYPE_ADHOC:
1265		if (wdev->current_bss) {
1266			*chan = wdev->current_bss->pub.channel;
1267			*chanmode = (wdev->ibss_fixed &&
1268				     !wdev->ibss_dfs_possible)
1269				  ? CHAN_MODE_SHARED
1270				  : CHAN_MODE_EXCLUSIVE;
1271
1272			/* consider worst-case - IBSS can try to return to the
1273			 * original user-specified channel as creator */
1274			if (wdev->ibss_dfs_possible)
1275				*radar_detect |= BIT(wdev->chandef.width);
1276			return;
1277		}
1278		break;
1279	case NL80211_IFTYPE_STATION:
1280	case NL80211_IFTYPE_P2P_CLIENT:
1281		if (wdev->current_bss) {
1282			*chan = wdev->current_bss->pub.channel;
1283			*chanmode = CHAN_MODE_SHARED;
1284			return;
1285		}
1286		break;
1287	case NL80211_IFTYPE_AP:
1288	case NL80211_IFTYPE_P2P_GO:
1289		if (wdev->cac_started) {
1290			*chan = wdev->chandef.chan;
1291			*chanmode = CHAN_MODE_SHARED;
1292			*radar_detect |= BIT(wdev->chandef.width);
1293		} else if (wdev->beacon_interval) {
1294			*chan = wdev->chandef.chan;
1295			*chanmode = CHAN_MODE_SHARED;
1296
1297			ret = cfg80211_chandef_dfs_required(wdev->wiphy,
1298							    &wdev->chandef,
1299							    wdev->iftype);
1300			WARN_ON(ret < 0);
1301			if (ret > 0)
1302				*radar_detect |= BIT(wdev->chandef.width);
1303		}
1304		return;
1305	case NL80211_IFTYPE_MESH_POINT:
1306		if (wdev->mesh_id_len) {
1307			*chan = wdev->chandef.chan;
1308			*chanmode = CHAN_MODE_SHARED;
1309
1310			ret = cfg80211_chandef_dfs_required(wdev->wiphy,
1311							    &wdev->chandef,
1312							    wdev->iftype);
1313			WARN_ON(ret < 0);
1314			if (ret > 0)
1315				*radar_detect |= BIT(wdev->chandef.width);
1316		}
1317		return;
1318	case NL80211_IFTYPE_OCB:
1319		if (wdev->chandef.chan) {
1320			*chan = wdev->chandef.chan;
1321			*chanmode = CHAN_MODE_SHARED;
1322			return;
1323		}
1324		break;
1325	case NL80211_IFTYPE_MONITOR:
1326	case NL80211_IFTYPE_AP_VLAN:
1327	case NL80211_IFTYPE_WDS:
1328	case NL80211_IFTYPE_P2P_DEVICE:
1329	case NL80211_IFTYPE_NAN:
1330		/* these interface types don't really have a channel */
1331		return;
1332	case NL80211_IFTYPE_UNSPECIFIED:
1333	case NUM_NL80211_IFTYPES:
1334		WARN_ON(1);
1335	}
1336}
1337