xref: /openbmc/linux/net/wireless/chan.c (revision a16be368) 
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 <net/cfg80211.h>
14 #include "core.h"
15 #include "rdev-ops.h"
16 
17 static bool cfg80211_valid_60g_freq(u32 freq)
18 {
19 	return freq >= 58320 && freq <= 70200;
20 }
21 
22 void cfg80211_chandef_create(struct cfg80211_chan_def *chandef,
23 			     struct ieee80211_channel *chan,
24 			     enum nl80211_channel_type chan_type)
25 {
26 	if (WARN_ON(!chan))
27 		return;
28 
29 	chandef->chan = chan;
30 	chandef->freq1_offset = chan->freq_offset;
31 	chandef->center_freq2 = 0;
32 	chandef->edmg.bw_config = 0;
33 	chandef->edmg.channels = 0;
34 
35 	switch (chan_type) {
36 	case NL80211_CHAN_NO_HT:
37 		chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
38 		chandef->center_freq1 = chan->center_freq;
39 		break;
40 	case NL80211_CHAN_HT20:
41 		chandef->width = NL80211_CHAN_WIDTH_20;
42 		chandef->center_freq1 = chan->center_freq;
43 		break;
44 	case NL80211_CHAN_HT40PLUS:
45 		chandef->width = NL80211_CHAN_WIDTH_40;
46 		chandef->center_freq1 = chan->center_freq + 10;
47 		break;
48 	case NL80211_CHAN_HT40MINUS:
49 		chandef->width = NL80211_CHAN_WIDTH_40;
50 		chandef->center_freq1 = chan->center_freq - 10;
51 		break;
52 	default:
53 		WARN_ON(1);
54 	}
55 }
56 EXPORT_SYMBOL(cfg80211_chandef_create);
57 
58 static bool cfg80211_edmg_chandef_valid(const struct cfg80211_chan_def *chandef)
59 {
60 	int max_contiguous = 0;
61 	int num_of_enabled = 0;
62 	int contiguous = 0;
63 	int i;
64 
65 	if (!chandef->edmg.channels || !chandef->edmg.bw_config)
66 		return false;
67 
68 	if (!cfg80211_valid_60g_freq(chandef->chan->center_freq))
69 		return false;
70 
71 	for (i = 0; i < 6; i++) {
72 		if (chandef->edmg.channels & BIT(i)) {
73 			contiguous++;
74 			num_of_enabled++;
75 		} else {
76 			contiguous = 0;
77 		}
78 
79 		max_contiguous = max(contiguous, max_contiguous);
80 	}
81 	/* basic verification of edmg configuration according to
82 	 * IEEE P802.11ay/D4.0 section 9.4.2.251
83 	 */
84 	/* check bw_config against contiguous edmg channels */
85 	switch (chandef->edmg.bw_config) {
86 	case IEEE80211_EDMG_BW_CONFIG_4:
87 	case IEEE80211_EDMG_BW_CONFIG_8:
88 	case IEEE80211_EDMG_BW_CONFIG_12:
89 		if (max_contiguous < 1)
90 			return false;
91 		break;
92 	case IEEE80211_EDMG_BW_CONFIG_5:
93 	case IEEE80211_EDMG_BW_CONFIG_9:
94 	case IEEE80211_EDMG_BW_CONFIG_13:
95 		if (max_contiguous < 2)
96 			return false;
97 		break;
98 	case IEEE80211_EDMG_BW_CONFIG_6:
99 	case IEEE80211_EDMG_BW_CONFIG_10:
100 	case IEEE80211_EDMG_BW_CONFIG_14:
101 		if (max_contiguous < 3)
102 			return false;
103 		break;
104 	case IEEE80211_EDMG_BW_CONFIG_7:
105 	case IEEE80211_EDMG_BW_CONFIG_11:
106 	case IEEE80211_EDMG_BW_CONFIG_15:
107 		if (max_contiguous < 4)
108 			return false;
109 		break;
110 
111 	default:
112 		return false;
113 	}
114 
115 	/* check bw_config against aggregated (non contiguous) edmg channels */
116 	switch (chandef->edmg.bw_config) {
117 	case IEEE80211_EDMG_BW_CONFIG_4:
118 	case IEEE80211_EDMG_BW_CONFIG_5:
119 	case IEEE80211_EDMG_BW_CONFIG_6:
120 	case IEEE80211_EDMG_BW_CONFIG_7:
121 		break;
122 	case IEEE80211_EDMG_BW_CONFIG_8:
123 	case IEEE80211_EDMG_BW_CONFIG_9:
124 	case IEEE80211_EDMG_BW_CONFIG_10:
125 	case IEEE80211_EDMG_BW_CONFIG_11:
126 		if (num_of_enabled < 2)
127 			return false;
128 		break;
129 	case IEEE80211_EDMG_BW_CONFIG_12:
130 	case IEEE80211_EDMG_BW_CONFIG_13:
131 	case IEEE80211_EDMG_BW_CONFIG_14:
132 	case IEEE80211_EDMG_BW_CONFIG_15:
133 		if (num_of_enabled < 4 || max_contiguous < 2)
134 			return false;
135 		break;
136 	default:
137 		return false;
138 	}
139 
140 	return true;
141 }
142 
143 bool cfg80211_chandef_valid(const struct cfg80211_chan_def *chandef)
144 {
145 	u32 control_freq;
146 
147 	if (!chandef->chan)
148 		return false;
149 
150 	if (chandef->freq1_offset >= 1000)
151 		return false;
152 
153 	control_freq = chandef->chan->center_freq;
154 
155 	switch (chandef->width) {
156 	case NL80211_CHAN_WIDTH_5:
157 	case NL80211_CHAN_WIDTH_10:
158 	case NL80211_CHAN_WIDTH_20:
159 	case NL80211_CHAN_WIDTH_20_NOHT:
160 		if (ieee80211_chandef_to_khz(chandef) !=
161 		    ieee80211_channel_to_khz(chandef->chan))
162 			return false;
163 		if (chandef->center_freq2)
164 			return false;
165 		break;
166 	case NL80211_CHAN_WIDTH_40:
167 		if (chandef->center_freq1 != control_freq + 10 &&
168 		    chandef->center_freq1 != control_freq - 10)
169 			return false;
170 		if (chandef->center_freq2)
171 			return false;
172 		break;
173 	case NL80211_CHAN_WIDTH_80P80:
174 		if (chandef->center_freq1 != control_freq + 30 &&
175 		    chandef->center_freq1 != control_freq + 10 &&
176 		    chandef->center_freq1 != control_freq - 10 &&
177 		    chandef->center_freq1 != control_freq - 30)
178 			return false;
179 		if (!chandef->center_freq2)
180 			return false;
181 		/* adjacent is not allowed -- that's a 160 MHz channel */
182 		if (chandef->center_freq1 - chandef->center_freq2 == 80 ||
183 		    chandef->center_freq2 - chandef->center_freq1 == 80)
184 			return false;
185 		break;
186 	case NL80211_CHAN_WIDTH_80:
187 		if (chandef->center_freq1 != control_freq + 30 &&
188 		    chandef->center_freq1 != control_freq + 10 &&
189 		    chandef->center_freq1 != control_freq - 10 &&
190 		    chandef->center_freq1 != control_freq - 30)
191 			return false;
192 		if (chandef->center_freq2)
193 			return false;
194 		break;
195 	case NL80211_CHAN_WIDTH_160:
196 		if (chandef->center_freq1 != control_freq + 70 &&
197 		    chandef->center_freq1 != control_freq + 50 &&
198 		    chandef->center_freq1 != control_freq + 30 &&
199 		    chandef->center_freq1 != control_freq + 10 &&
200 		    chandef->center_freq1 != control_freq - 10 &&
201 		    chandef->center_freq1 != control_freq - 30 &&
202 		    chandef->center_freq1 != control_freq - 50 &&
203 		    chandef->center_freq1 != control_freq - 70)
204 			return false;
205 		if (chandef->center_freq2)
206 			return false;
207 		break;
208 	default:
209 		return false;
210 	}
211 
212 	/* channel 14 is only for IEEE 802.11b */
213 	if (chandef->center_freq1 == 2484 &&
214 	    chandef->width != NL80211_CHAN_WIDTH_20_NOHT)
215 		return false;
216 
217 	if (cfg80211_chandef_is_edmg(chandef) &&
218 	    !cfg80211_edmg_chandef_valid(chandef))
219 		return false;
220 
221 	return true;
222 }
223 EXPORT_SYMBOL(cfg80211_chandef_valid);
224 
225 static void chandef_primary_freqs(const struct cfg80211_chan_def *c,
226 				  u32 *pri40, u32 *pri80)
227 {
228 	int tmp;
229 
230 	switch (c->width) {
231 	case NL80211_CHAN_WIDTH_40:
232 		*pri40 = c->center_freq1;
233 		*pri80 = 0;
234 		break;
235 	case NL80211_CHAN_WIDTH_80:
236 	case NL80211_CHAN_WIDTH_80P80:
237 		*pri80 = c->center_freq1;
238 		/* n_P20 */
239 		tmp = (30 + c->chan->center_freq - c->center_freq1)/20;
240 		/* n_P40 */
241 		tmp /= 2;
242 		/* freq_P40 */
243 		*pri40 = c->center_freq1 - 20 + 40 * tmp;
244 		break;
245 	case NL80211_CHAN_WIDTH_160:
246 		/* n_P20 */
247 		tmp = (70 + c->chan->center_freq - c->center_freq1)/20;
248 		/* n_P40 */
249 		tmp /= 2;
250 		/* freq_P40 */
251 		*pri40 = c->center_freq1 - 60 + 40 * tmp;
252 		/* n_P80 */
253 		tmp /= 2;
254 		*pri80 = c->center_freq1 - 40 + 80 * tmp;
255 		break;
256 	default:
257 		WARN_ON_ONCE(1);
258 	}
259 }
260 
261 static int cfg80211_chandef_get_width(const struct cfg80211_chan_def *c)
262 {
263 	int width;
264 
265 	switch (c->width) {
266 	case NL80211_CHAN_WIDTH_5:
267 		width = 5;
268 		break;
269 	case NL80211_CHAN_WIDTH_10:
270 		width = 10;
271 		break;
272 	case NL80211_CHAN_WIDTH_20:
273 	case NL80211_CHAN_WIDTH_20_NOHT:
274 		width = 20;
275 		break;
276 	case NL80211_CHAN_WIDTH_40:
277 		width = 40;
278 		break;
279 	case NL80211_CHAN_WIDTH_80P80:
280 	case NL80211_CHAN_WIDTH_80:
281 		width = 80;
282 		break;
283 	case NL80211_CHAN_WIDTH_160:
284 		width = 160;
285 		break;
286 	default:
287 		WARN_ON_ONCE(1);
288 		return -1;
289 	}
290 	return width;
291 }
292 
293 const struct cfg80211_chan_def *
294 cfg80211_chandef_compatible(const struct cfg80211_chan_def *c1,
295 			    const struct cfg80211_chan_def *c2)
296 {
297 	u32 c1_pri40, c1_pri80, c2_pri40, c2_pri80;
298 
299 	/* If they are identical, return */
300 	if (cfg80211_chandef_identical(c1, c2))
301 		return c1;
302 
303 	/* otherwise, must have same control channel */
304 	if (c1->chan != c2->chan)
305 		return NULL;
306 
307 	/*
308 	 * If they have the same width, but aren't identical,
309 	 * then they can't be compatible.
310 	 */
311 	if (c1->width == c2->width)
312 		return NULL;
313 
314 	/*
315 	 * can't be compatible if one of them is 5 or 10 MHz,
316 	 * but they don't have the same width.
317 	 */
318 	if (c1->width == NL80211_CHAN_WIDTH_5 ||
319 	    c1->width == NL80211_CHAN_WIDTH_10 ||
320 	    c2->width == NL80211_CHAN_WIDTH_5 ||
321 	    c2->width == NL80211_CHAN_WIDTH_10)
322 		return NULL;
323 
324 	if (c1->width == NL80211_CHAN_WIDTH_20_NOHT ||
325 	    c1->width == NL80211_CHAN_WIDTH_20)
326 		return c2;
327 
328 	if (c2->width == NL80211_CHAN_WIDTH_20_NOHT ||
329 	    c2->width == NL80211_CHAN_WIDTH_20)
330 		return c1;
331 
332 	chandef_primary_freqs(c1, &c1_pri40, &c1_pri80);
333 	chandef_primary_freqs(c2, &c2_pri40, &c2_pri80);
334 
335 	if (c1_pri40 != c2_pri40)
336 		return NULL;
337 
338 	WARN_ON(!c1_pri80 && !c2_pri80);
339 	if (c1_pri80 && c2_pri80 && c1_pri80 != c2_pri80)
340 		return NULL;
341 
342 	if (c1->width > c2->width)
343 		return c1;
344 	return c2;
345 }
346 EXPORT_SYMBOL(cfg80211_chandef_compatible);
347 
348 static void cfg80211_set_chans_dfs_state(struct wiphy *wiphy, u32 center_freq,
349 					 u32 bandwidth,
350 					 enum nl80211_dfs_state dfs_state)
351 {
352 	struct ieee80211_channel *c;
353 	u32 freq;
354 
355 	for (freq = center_freq - bandwidth/2 + 10;
356 	     freq <= center_freq + bandwidth/2 - 10;
357 	     freq += 20) {
358 		c = ieee80211_get_channel(wiphy, freq);
359 		if (!c || !(c->flags & IEEE80211_CHAN_RADAR))
360 			continue;
361 
362 		c->dfs_state = dfs_state;
363 		c->dfs_state_entered = jiffies;
364 	}
365 }
366 
367 void cfg80211_set_dfs_state(struct wiphy *wiphy,
368 			    const struct cfg80211_chan_def *chandef,
369 			    enum nl80211_dfs_state dfs_state)
370 {
371 	int width;
372 
373 	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
374 		return;
375 
376 	width = cfg80211_chandef_get_width(chandef);
377 	if (width < 0)
378 		return;
379 
380 	cfg80211_set_chans_dfs_state(wiphy, chandef->center_freq1,
381 				     width, dfs_state);
382 
383 	if (!chandef->center_freq2)
384 		return;
385 	cfg80211_set_chans_dfs_state(wiphy, chandef->center_freq2,
386 				     width, dfs_state);
387 }
388 
389 static u32 cfg80211_get_start_freq(u32 center_freq,
390 				   u32 bandwidth)
391 {
392 	u32 start_freq;
393 
394 	bandwidth = MHZ_TO_KHZ(bandwidth);
395 	if (bandwidth <= MHZ_TO_KHZ(20))
396 		start_freq = center_freq;
397 	else
398 		start_freq = center_freq - bandwidth / 2 + MHZ_TO_KHZ(10);
399 
400 	return start_freq;
401 }
402 
403 static u32 cfg80211_get_end_freq(u32 center_freq,
404 				 u32 bandwidth)
405 {
406 	u32 end_freq;
407 
408 	bandwidth = MHZ_TO_KHZ(bandwidth);
409 	if (bandwidth <= MHZ_TO_KHZ(20))
410 		end_freq = center_freq;
411 	else
412 		end_freq = center_freq + bandwidth / 2 - MHZ_TO_KHZ(10);
413 
414 	return end_freq;
415 }
416 
417 static int cfg80211_get_chans_dfs_required(struct wiphy *wiphy,
418 					    u32 center_freq,
419 					    u32 bandwidth)
420 {
421 	struct ieee80211_channel *c;
422 	u32 freq, start_freq, end_freq;
423 
424 	start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
425 	end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
426 
427 	for (freq = start_freq; freq <= end_freq; freq += MHZ_TO_KHZ(20)) {
428 		c = ieee80211_get_channel_khz(wiphy, freq);
429 		if (!c)
430 			return -EINVAL;
431 
432 		if (c->flags & IEEE80211_CHAN_RADAR)
433 			return 1;
434 	}
435 	return 0;
436 }
437 
438 
439 int cfg80211_chandef_dfs_required(struct wiphy *wiphy,
440 				  const struct cfg80211_chan_def *chandef,
441 				  enum nl80211_iftype iftype)
442 {
443 	int width;
444 	int ret;
445 
446 	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
447 		return -EINVAL;
448 
449 	switch (iftype) {
450 	case NL80211_IFTYPE_ADHOC:
451 	case NL80211_IFTYPE_AP:
452 	case NL80211_IFTYPE_P2P_GO:
453 	case NL80211_IFTYPE_MESH_POINT:
454 		width = cfg80211_chandef_get_width(chandef);
455 		if (width < 0)
456 			return -EINVAL;
457 
458 		ret = cfg80211_get_chans_dfs_required(wiphy,
459 					ieee80211_chandef_to_khz(chandef),
460 					width);
461 		if (ret < 0)
462 			return ret;
463 		else if (ret > 0)
464 			return BIT(chandef->width);
465 
466 		if (!chandef->center_freq2)
467 			return 0;
468 
469 		ret = cfg80211_get_chans_dfs_required(wiphy,
470 					MHZ_TO_KHZ(chandef->center_freq2),
471 					width);
472 		if (ret < 0)
473 			return ret;
474 		else if (ret > 0)
475 			return BIT(chandef->width);
476 
477 		break;
478 	case NL80211_IFTYPE_STATION:
479 	case NL80211_IFTYPE_OCB:
480 	case NL80211_IFTYPE_P2P_CLIENT:
481 	case NL80211_IFTYPE_MONITOR:
482 	case NL80211_IFTYPE_AP_VLAN:
483 	case NL80211_IFTYPE_WDS:
484 	case NL80211_IFTYPE_P2P_DEVICE:
485 	case NL80211_IFTYPE_NAN:
486 		break;
487 	case NL80211_IFTYPE_UNSPECIFIED:
488 	case NUM_NL80211_IFTYPES:
489 		WARN_ON(1);
490 	}
491 
492 	return 0;
493 }
494 EXPORT_SYMBOL(cfg80211_chandef_dfs_required);
495 
496 static int cfg80211_get_chans_dfs_usable(struct wiphy *wiphy,
497 					 u32 center_freq,
498 					 u32 bandwidth)
499 {
500 	struct ieee80211_channel *c;
501 	u32 freq, start_freq, end_freq;
502 	int count = 0;
503 
504 	start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
505 	end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
506 
507 	/*
508 	 * Check entire range of channels for the bandwidth.
509 	 * Check all channels are DFS channels (DFS_USABLE or
510 	 * DFS_AVAILABLE). Return number of usable channels
511 	 * (require CAC). Allow DFS and non-DFS channel mix.
512 	 */
513 	for (freq = start_freq; freq <= end_freq; freq += MHZ_TO_KHZ(20)) {
514 		c = ieee80211_get_channel_khz(wiphy, freq);
515 		if (!c)
516 			return -EINVAL;
517 
518 		if (c->flags & IEEE80211_CHAN_DISABLED)
519 			return -EINVAL;
520 
521 		if (c->flags & IEEE80211_CHAN_RADAR) {
522 			if (c->dfs_state == NL80211_DFS_UNAVAILABLE)
523 				return -EINVAL;
524 
525 			if (c->dfs_state == NL80211_DFS_USABLE)
526 				count++;
527 		}
528 	}
529 
530 	return count;
531 }
532 
533 bool cfg80211_chandef_dfs_usable(struct wiphy *wiphy,
534 				 const struct cfg80211_chan_def *chandef)
535 {
536 	int width;
537 	int r1, r2 = 0;
538 
539 	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
540 		return false;
541 
542 	width = cfg80211_chandef_get_width(chandef);
543 	if (width < 0)
544 		return false;
545 
546 	r1 = cfg80211_get_chans_dfs_usable(wiphy,
547 					   MHZ_TO_KHZ(chandef->center_freq1),
548 					   width);
549 
550 	if (r1 < 0)
551 		return false;
552 
553 	switch (chandef->width) {
554 	case NL80211_CHAN_WIDTH_80P80:
555 		WARN_ON(!chandef->center_freq2);
556 		r2 = cfg80211_get_chans_dfs_usable(wiphy,
557 					MHZ_TO_KHZ(chandef->center_freq2),
558 					width);
559 		if (r2 < 0)
560 			return false;
561 		break;
562 	default:
563 		WARN_ON(chandef->center_freq2);
564 		break;
565 	}
566 
567 	return (r1 + r2 > 0);
568 }
569 
570 /*
571  * Checks if center frequency of chan falls with in the bandwidth
572  * range of chandef.
573  */
574 bool cfg80211_is_sub_chan(struct cfg80211_chan_def *chandef,
575 			  struct ieee80211_channel *chan)
576 {
577 	int width;
578 	u32 freq;
579 
580 	if (chandef->chan->center_freq == chan->center_freq)
581 		return true;
582 
583 	width = cfg80211_chandef_get_width(chandef);
584 	if (width <= 20)
585 		return false;
586 
587 	for (freq = chandef->center_freq1 - width / 2 + 10;
588 	     freq <= chandef->center_freq1 + width / 2 - 10; freq += 20) {
589 		if (chan->center_freq == freq)
590 			return true;
591 	}
592 
593 	if (!chandef->center_freq2)
594 		return false;
595 
596 	for (freq = chandef->center_freq2 - width / 2 + 10;
597 	     freq <= chandef->center_freq2 + width / 2 - 10; freq += 20) {
598 		if (chan->center_freq == freq)
599 			return true;
600 	}
601 
602 	return false;
603 }
604 
605 bool cfg80211_beaconing_iface_active(struct wireless_dev *wdev)
606 {
607 	bool active = false;
608 
609 	ASSERT_WDEV_LOCK(wdev);
610 
611 	if (!wdev->chandef.chan)
612 		return false;
613 
614 	switch (wdev->iftype) {
615 	case NL80211_IFTYPE_AP:
616 	case NL80211_IFTYPE_P2P_GO:
617 		active = wdev->beacon_interval != 0;
618 		break;
619 	case NL80211_IFTYPE_ADHOC:
620 		active = wdev->ssid_len != 0;
621 		break;
622 	case NL80211_IFTYPE_MESH_POINT:
623 		active = wdev->mesh_id_len != 0;
624 		break;
625 	case NL80211_IFTYPE_STATION:
626 	case NL80211_IFTYPE_OCB:
627 	case NL80211_IFTYPE_P2P_CLIENT:
628 	case NL80211_IFTYPE_MONITOR:
629 	case NL80211_IFTYPE_AP_VLAN:
630 	case NL80211_IFTYPE_WDS:
631 	case NL80211_IFTYPE_P2P_DEVICE:
632 	/* Can NAN type be considered as beaconing interface? */
633 	case NL80211_IFTYPE_NAN:
634 		break;
635 	case NL80211_IFTYPE_UNSPECIFIED:
636 	case NUM_NL80211_IFTYPES:
637 		WARN_ON(1);
638 	}
639 
640 	return active;
641 }
642 
643 static bool cfg80211_is_wiphy_oper_chan(struct wiphy *wiphy,
644 					struct ieee80211_channel *chan)
645 {
646 	struct wireless_dev *wdev;
647 
648 	list_for_each_entry(wdev, &wiphy->wdev_list, list) {
649 		wdev_lock(wdev);
650 		if (!cfg80211_beaconing_iface_active(wdev)) {
651 			wdev_unlock(wdev);
652 			continue;
653 		}
654 
655 		if (cfg80211_is_sub_chan(&wdev->chandef, chan)) {
656 			wdev_unlock(wdev);
657 			return true;
658 		}
659 		wdev_unlock(wdev);
660 	}
661 
662 	return false;
663 }
664 
665 bool cfg80211_any_wiphy_oper_chan(struct wiphy *wiphy,
666 				  struct ieee80211_channel *chan)
667 {
668 	struct cfg80211_registered_device *rdev;
669 
670 	ASSERT_RTNL();
671 
672 	if (!(chan->flags & IEEE80211_CHAN_RADAR))
673 		return false;
674 
675 	list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
676 		if (!reg_dfs_domain_same(wiphy, &rdev->wiphy))
677 			continue;
678 
679 		if (cfg80211_is_wiphy_oper_chan(&rdev->wiphy, chan))
680 			return true;
681 	}
682 
683 	return false;
684 }
685 
686 static bool cfg80211_get_chans_dfs_available(struct wiphy *wiphy,
687 					     u32 center_freq,
688 					     u32 bandwidth)
689 {
690 	struct ieee80211_channel *c;
691 	u32 freq, start_freq, end_freq;
692 	bool dfs_offload;
693 
694 	dfs_offload = wiphy_ext_feature_isset(wiphy,
695 					      NL80211_EXT_FEATURE_DFS_OFFLOAD);
696 
697 	start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
698 	end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
699 
700 	/*
701 	 * Check entire range of channels for the bandwidth.
702 	 * If any channel in between is disabled or has not
703 	 * had gone through CAC return false
704 	 */
705 	for (freq = start_freq; freq <= end_freq; freq += MHZ_TO_KHZ(20)) {
706 		c = ieee80211_get_channel_khz(wiphy, freq);
707 		if (!c)
708 			return false;
709 
710 		if (c->flags & IEEE80211_CHAN_DISABLED)
711 			return false;
712 
713 		if ((c->flags & IEEE80211_CHAN_RADAR) &&
714 		    (c->dfs_state != NL80211_DFS_AVAILABLE) &&
715 		    !(c->dfs_state == NL80211_DFS_USABLE && dfs_offload))
716 			return false;
717 	}
718 
719 	return true;
720 }
721 
722 static bool cfg80211_chandef_dfs_available(struct wiphy *wiphy,
723 				const struct cfg80211_chan_def *chandef)
724 {
725 	int width;
726 	int r;
727 
728 	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
729 		return false;
730 
731 	width = cfg80211_chandef_get_width(chandef);
732 	if (width < 0)
733 		return false;
734 
735 	r = cfg80211_get_chans_dfs_available(wiphy,
736 					     MHZ_TO_KHZ(chandef->center_freq1),
737 					     width);
738 
739 	/* If any of channels unavailable for cf1 just return */
740 	if (!r)
741 		return r;
742 
743 	switch (chandef->width) {
744 	case NL80211_CHAN_WIDTH_80P80:
745 		WARN_ON(!chandef->center_freq2);
746 		r = cfg80211_get_chans_dfs_available(wiphy,
747 					MHZ_TO_KHZ(chandef->center_freq2),
748 					width);
749 		break;
750 	default:
751 		WARN_ON(chandef->center_freq2);
752 		break;
753 	}
754 
755 	return r;
756 }
757 
758 static unsigned int cfg80211_get_chans_dfs_cac_time(struct wiphy *wiphy,
759 						    u32 center_freq,
760 						    u32 bandwidth)
761 {
762 	struct ieee80211_channel *c;
763 	u32 start_freq, end_freq, freq;
764 	unsigned int dfs_cac_ms = 0;
765 
766 	start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
767 	end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
768 
769 	for (freq = start_freq; freq <= end_freq; freq += MHZ_TO_KHZ(20)) {
770 		c = ieee80211_get_channel_khz(wiphy, freq);
771 		if (!c)
772 			return 0;
773 
774 		if (c->flags & IEEE80211_CHAN_DISABLED)
775 			return 0;
776 
777 		if (!(c->flags & IEEE80211_CHAN_RADAR))
778 			continue;
779 
780 		if (c->dfs_cac_ms > dfs_cac_ms)
781 			dfs_cac_ms = c->dfs_cac_ms;
782 	}
783 
784 	return dfs_cac_ms;
785 }
786 
787 unsigned int
788 cfg80211_chandef_dfs_cac_time(struct wiphy *wiphy,
789 			      const struct cfg80211_chan_def *chandef)
790 {
791 	int width;
792 	unsigned int t1 = 0, t2 = 0;
793 
794 	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
795 		return 0;
796 
797 	width = cfg80211_chandef_get_width(chandef);
798 	if (width < 0)
799 		return 0;
800 
801 	t1 = cfg80211_get_chans_dfs_cac_time(wiphy,
802 					     MHZ_TO_KHZ(chandef->center_freq1),
803 					     width);
804 
805 	if (!chandef->center_freq2)
806 		return t1;
807 
808 	t2 = cfg80211_get_chans_dfs_cac_time(wiphy,
809 					     MHZ_TO_KHZ(chandef->center_freq2),
810 					     width);
811 
812 	return max(t1, t2);
813 }
814 
815 static bool cfg80211_secondary_chans_ok(struct wiphy *wiphy,
816 					u32 center_freq, u32 bandwidth,
817 					u32 prohibited_flags)
818 {
819 	struct ieee80211_channel *c;
820 	u32 freq, start_freq, end_freq;
821 
822 	start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
823 	end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
824 
825 	for (freq = start_freq; freq <= end_freq; freq += MHZ_TO_KHZ(20)) {
826 		c = ieee80211_get_channel_khz(wiphy, freq);
827 		if (!c || c->flags & prohibited_flags)
828 			return false;
829 	}
830 
831 	return true;
832 }
833 
834 /* check if the operating channels are valid and supported */
835 static bool cfg80211_edmg_usable(struct wiphy *wiphy, u8 edmg_channels,
836 				 enum ieee80211_edmg_bw_config edmg_bw_config,
837 				 int primary_channel,
838 				 struct ieee80211_edmg *edmg_cap)
839 {
840 	struct ieee80211_channel *chan;
841 	int i, freq;
842 	int channels_counter = 0;
843 
844 	if (!edmg_channels && !edmg_bw_config)
845 		return true;
846 
847 	if ((!edmg_channels && edmg_bw_config) ||
848 	    (edmg_channels && !edmg_bw_config))
849 		return false;
850 
851 	if (!(edmg_channels & BIT(primary_channel - 1)))
852 		return false;
853 
854 	/* 60GHz channels 1..6 */
855 	for (i = 0; i < 6; i++) {
856 		if (!(edmg_channels & BIT(i)))
857 			continue;
858 
859 		if (!(edmg_cap->channels & BIT(i)))
860 			return false;
861 
862 		channels_counter++;
863 
864 		freq = ieee80211_channel_to_frequency(i + 1,
865 						      NL80211_BAND_60GHZ);
866 		chan = ieee80211_get_channel(wiphy, freq);
867 		if (!chan || chan->flags & IEEE80211_CHAN_DISABLED)
868 			return false;
869 	}
870 
871 	/* IEEE802.11 allows max 4 channels */
872 	if (channels_counter > 4)
873 		return false;
874 
875 	/* check bw_config is a subset of what driver supports
876 	 * (see IEEE P802.11ay/D4.0 section 9.4.2.251, Table 13)
877 	 */
878 	if ((edmg_bw_config % 4) > (edmg_cap->bw_config % 4))
879 		return false;
880 
881 	if (edmg_bw_config > edmg_cap->bw_config)
882 		return false;
883 
884 	return true;
885 }
886 
887 bool cfg80211_chandef_usable(struct wiphy *wiphy,
888 			     const struct cfg80211_chan_def *chandef,
889 			     u32 prohibited_flags)
890 {
891 	struct ieee80211_sta_ht_cap *ht_cap;
892 	struct ieee80211_sta_vht_cap *vht_cap;
893 	struct ieee80211_edmg *edmg_cap;
894 	u32 width, control_freq, cap;
895 
896 	if (WARN_ON(!cfg80211_chandef_valid(chandef)))
897 		return false;
898 
899 	ht_cap = &wiphy->bands[chandef->chan->band]->ht_cap;
900 	vht_cap = &wiphy->bands[chandef->chan->band]->vht_cap;
901 	edmg_cap = &wiphy->bands[chandef->chan->band]->edmg_cap;
902 
903 	if (edmg_cap->channels &&
904 	    !cfg80211_edmg_usable(wiphy,
905 				  chandef->edmg.channels,
906 				  chandef->edmg.bw_config,
907 				  chandef->chan->hw_value,
908 				  edmg_cap))
909 		return false;
910 
911 	control_freq = chandef->chan->center_freq;
912 
913 	switch (chandef->width) {
914 	case NL80211_CHAN_WIDTH_5:
915 		width = 5;
916 		break;
917 	case NL80211_CHAN_WIDTH_10:
918 		prohibited_flags |= IEEE80211_CHAN_NO_10MHZ;
919 		width = 10;
920 		break;
921 	case NL80211_CHAN_WIDTH_20:
922 		if (!ht_cap->ht_supported &&
923 		    chandef->chan->band != NL80211_BAND_6GHZ)
924 			return false;
925 		/* fall through */
926 	case NL80211_CHAN_WIDTH_20_NOHT:
927 		prohibited_flags |= IEEE80211_CHAN_NO_20MHZ;
928 		width = 20;
929 		break;
930 	case NL80211_CHAN_WIDTH_40:
931 		width = 40;
932 		if (chandef->chan->band == NL80211_BAND_6GHZ)
933 			break;
934 		if (!ht_cap->ht_supported)
935 			return false;
936 		if (!(ht_cap->cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) ||
937 		    ht_cap->cap & IEEE80211_HT_CAP_40MHZ_INTOLERANT)
938 			return false;
939 		if (chandef->center_freq1 < control_freq &&
940 		    chandef->chan->flags & IEEE80211_CHAN_NO_HT40MINUS)
941 			return false;
942 		if (chandef->center_freq1 > control_freq &&
943 		    chandef->chan->flags & IEEE80211_CHAN_NO_HT40PLUS)
944 			return false;
945 		break;
946 	case NL80211_CHAN_WIDTH_80P80:
947 		cap = vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
948 		if (chandef->chan->band != NL80211_BAND_6GHZ &&
949 		    cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
950 			return false;
951 		/* fall through */
952 	case NL80211_CHAN_WIDTH_80:
953 		prohibited_flags |= IEEE80211_CHAN_NO_80MHZ;
954 		width = 80;
955 		if (chandef->chan->band == NL80211_BAND_6GHZ)
956 			break;
957 		if (!vht_cap->vht_supported)
958 			return false;
959 		break;
960 	case NL80211_CHAN_WIDTH_160:
961 		prohibited_flags |= IEEE80211_CHAN_NO_160MHZ;
962 		width = 160;
963 		if (chandef->chan->band == NL80211_BAND_6GHZ)
964 			break;
965 		if (!vht_cap->vht_supported)
966 			return false;
967 		cap = vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
968 		if (cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ &&
969 		    cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
970 			return false;
971 		break;
972 	default:
973 		WARN_ON_ONCE(1);
974 		return false;
975 	}
976 
977 	/*
978 	 * TODO: What if there are only certain 80/160/80+80 MHz channels
979 	 *	 allowed by the driver, or only certain combinations?
980 	 *	 For 40 MHz the driver can set the NO_HT40 flags, but for
981 	 *	 80/160 MHz and in particular 80+80 MHz this isn't really
982 	 *	 feasible and we only have NO_80MHZ/NO_160MHZ so far but
983 	 *	 no way to cover 80+80 MHz or more complex restrictions.
984 	 *	 Note that such restrictions also need to be advertised to
985 	 *	 userspace, for example for P2P channel selection.
986 	 */
987 
988 	if (width > 20)
989 		prohibited_flags |= IEEE80211_CHAN_NO_OFDM;
990 
991 	/* 5 and 10 MHz are only defined for the OFDM PHY */
992 	if (width < 20)
993 		prohibited_flags |= IEEE80211_CHAN_NO_OFDM;
994 
995 
996 	if (!cfg80211_secondary_chans_ok(wiphy,
997 					 ieee80211_chandef_to_khz(chandef),
998 					 width, prohibited_flags))
999 		return false;
1000 
1001 	if (!chandef->center_freq2)
1002 		return true;
1003 	return cfg80211_secondary_chans_ok(wiphy,
1004 					   MHZ_TO_KHZ(chandef->center_freq2),
1005 					   width, prohibited_flags);
1006 }
1007 EXPORT_SYMBOL(cfg80211_chandef_usable);
1008 
1009 /*
1010  * Check if the channel can be used under permissive conditions mandated by
1011  * some regulatory bodies, i.e., the channel is marked with
1012  * IEEE80211_CHAN_IR_CONCURRENT and there is an additional station interface
1013  * associated to an AP on the same channel or on the same UNII band
1014  * (assuming that the AP is an authorized master).
1015  * In addition allow operation on a channel on which indoor operation is
1016  * allowed, iff we are currently operating in an indoor environment.
1017  */
1018 static bool cfg80211_ir_permissive_chan(struct wiphy *wiphy,
1019 					enum nl80211_iftype iftype,
1020 					struct ieee80211_channel *chan)
1021 {
1022 	struct wireless_dev *wdev;
1023 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
1024 
1025 	ASSERT_RTNL();
1026 
1027 	if (!IS_ENABLED(CONFIG_CFG80211_REG_RELAX_NO_IR) ||
1028 	    !(wiphy->regulatory_flags & REGULATORY_ENABLE_RELAX_NO_IR))
1029 		return false;
1030 
1031 	/* only valid for GO and TDLS off-channel (station/p2p-CL) */
1032 	if (iftype != NL80211_IFTYPE_P2P_GO &&
1033 	    iftype != NL80211_IFTYPE_STATION &&
1034 	    iftype != NL80211_IFTYPE_P2P_CLIENT)
1035 		return false;
1036 
1037 	if (regulatory_indoor_allowed() &&
1038 	    (chan->flags & IEEE80211_CHAN_INDOOR_ONLY))
1039 		return true;
1040 
1041 	if (!(chan->flags & IEEE80211_CHAN_IR_CONCURRENT))
1042 		return false;
1043 
1044 	/*
1045 	 * Generally, it is possible to rely on another device/driver to allow
1046 	 * the IR concurrent relaxation, however, since the device can further
1047 	 * enforce the relaxation (by doing a similar verifications as this),
1048 	 * and thus fail the GO instantiation, consider only the interfaces of
1049 	 * the current registered device.
1050 	 */
1051 	list_for_each_entry(wdev, &rdev->wiphy.wdev_list, list) {
1052 		struct ieee80211_channel *other_chan = NULL;
1053 		int r1, r2;
1054 
1055 		wdev_lock(wdev);
1056 		if (wdev->iftype == NL80211_IFTYPE_STATION &&
1057 		    wdev->current_bss)
1058 			other_chan = wdev->current_bss->pub.channel;
1059 
1060 		/*
1061 		 * If a GO already operates on the same GO_CONCURRENT channel,
1062 		 * this one (maybe the same one) can beacon as well. We allow
1063 		 * the operation even if the station we relied on with
1064 		 * GO_CONCURRENT is disconnected now. But then we must make sure
1065 		 * we're not outdoor on an indoor-only channel.
1066 		 */
1067 		if (iftype == NL80211_IFTYPE_P2P_GO &&
1068 		    wdev->iftype == NL80211_IFTYPE_P2P_GO &&
1069 		    wdev->beacon_interval &&
1070 		    !(chan->flags & IEEE80211_CHAN_INDOOR_ONLY))
1071 			other_chan = wdev->chandef.chan;
1072 		wdev_unlock(wdev);
1073 
1074 		if (!other_chan)
1075 			continue;
1076 
1077 		if (chan == other_chan)
1078 			return true;
1079 
1080 		if (chan->band != NL80211_BAND_5GHZ &&
1081 		    chan->band != NL80211_BAND_6GHZ)
1082 			continue;
1083 
1084 		r1 = cfg80211_get_unii(chan->center_freq);
1085 		r2 = cfg80211_get_unii(other_chan->center_freq);
1086 
1087 		if (r1 != -EINVAL && r1 == r2) {
1088 			/*
1089 			 * At some locations channels 149-165 are considered a
1090 			 * bundle, but at other locations, e.g., Indonesia,
1091 			 * channels 149-161 are considered a bundle while
1092 			 * channel 165 is left out and considered to be in a
1093 			 * different bundle. Thus, in case that there is a
1094 			 * station interface connected to an AP on channel 165,
1095 			 * it is assumed that channels 149-161 are allowed for
1096 			 * GO operations. However, having a station interface
1097 			 * connected to an AP on channels 149-161, does not
1098 			 * allow GO operation on channel 165.
1099 			 */
1100 			if (chan->center_freq == 5825 &&
1101 			    other_chan->center_freq != 5825)
1102 				continue;
1103 			return true;
1104 		}
1105 	}
1106 
1107 	return false;
1108 }
1109 
1110 static bool _cfg80211_reg_can_beacon(struct wiphy *wiphy,
1111 				     struct cfg80211_chan_def *chandef,
1112 				     enum nl80211_iftype iftype,
1113 				     bool check_no_ir)
1114 {
1115 	bool res;
1116 	u32 prohibited_flags = IEEE80211_CHAN_DISABLED |
1117 			       IEEE80211_CHAN_RADAR;
1118 
1119 	trace_cfg80211_reg_can_beacon(wiphy, chandef, iftype, check_no_ir);
1120 
1121 	if (check_no_ir)
1122 		prohibited_flags |= IEEE80211_CHAN_NO_IR;
1123 
1124 	if (cfg80211_chandef_dfs_required(wiphy, chandef, iftype) > 0 &&
1125 	    cfg80211_chandef_dfs_available(wiphy, chandef)) {
1126 		/* We can skip IEEE80211_CHAN_NO_IR if chandef dfs available */
1127 		prohibited_flags = IEEE80211_CHAN_DISABLED;
1128 	}
1129 
1130 	res = cfg80211_chandef_usable(wiphy, chandef, prohibited_flags);
1131 
1132 	trace_cfg80211_return_bool(res);
1133 	return res;
1134 }
1135 
1136 bool cfg80211_reg_can_beacon(struct wiphy *wiphy,
1137 			     struct cfg80211_chan_def *chandef,
1138 			     enum nl80211_iftype iftype)
1139 {
1140 	return _cfg80211_reg_can_beacon(wiphy, chandef, iftype, true);
1141 }
1142 EXPORT_SYMBOL(cfg80211_reg_can_beacon);
1143 
1144 bool cfg80211_reg_can_beacon_relax(struct wiphy *wiphy,
1145 				   struct cfg80211_chan_def *chandef,
1146 				   enum nl80211_iftype iftype)
1147 {
1148 	bool check_no_ir;
1149 
1150 	ASSERT_RTNL();
1151 
1152 	/*
1153 	 * Under certain conditions suggested by some regulatory bodies a
1154 	 * GO/STA can IR on channels marked with IEEE80211_NO_IR. Set this flag
1155 	 * only if such relaxations are not enabled and the conditions are not
1156 	 * met.
1157 	 */
1158 	check_no_ir = !cfg80211_ir_permissive_chan(wiphy, iftype,
1159 						   chandef->chan);
1160 
1161 	return _cfg80211_reg_can_beacon(wiphy, chandef, iftype, check_no_ir);
1162 }
1163 EXPORT_SYMBOL(cfg80211_reg_can_beacon_relax);
1164 
1165 int cfg80211_set_monitor_channel(struct cfg80211_registered_device *rdev,
1166 				 struct cfg80211_chan_def *chandef)
1167 {
1168 	if (!rdev->ops->set_monitor_channel)
1169 		return -EOPNOTSUPP;
1170 	if (!cfg80211_has_monitors_only(rdev))
1171 		return -EBUSY;
1172 
1173 	return rdev_set_monitor_channel(rdev, chandef);
1174 }
1175 
1176 void
1177 cfg80211_get_chan_state(struct wireless_dev *wdev,
1178 		        struct ieee80211_channel **chan,
1179 		        enum cfg80211_chan_mode *chanmode,
1180 		        u8 *radar_detect)
1181 {
1182 	int ret;
1183 
1184 	*chan = NULL;
1185 	*chanmode = CHAN_MODE_UNDEFINED;
1186 
1187 	ASSERT_WDEV_LOCK(wdev);
1188 
1189 	if (wdev->netdev && !netif_running(wdev->netdev))
1190 		return;
1191 
1192 	switch (wdev->iftype) {
1193 	case NL80211_IFTYPE_ADHOC:
1194 		if (wdev->current_bss) {
1195 			*chan = wdev->current_bss->pub.channel;
1196 			*chanmode = (wdev->ibss_fixed &&
1197 				     !wdev->ibss_dfs_possible)
1198 				  ? CHAN_MODE_SHARED
1199 				  : CHAN_MODE_EXCLUSIVE;
1200 
1201 			/* consider worst-case - IBSS can try to return to the
1202 			 * original user-specified channel as creator */
1203 			if (wdev->ibss_dfs_possible)
1204 				*radar_detect |= BIT(wdev->chandef.width);
1205 			return;
1206 		}
1207 		break;
1208 	case NL80211_IFTYPE_STATION:
1209 	case NL80211_IFTYPE_P2P_CLIENT:
1210 		if (wdev->current_bss) {
1211 			*chan = wdev->current_bss->pub.channel;
1212 			*chanmode = CHAN_MODE_SHARED;
1213 			return;
1214 		}
1215 		break;
1216 	case NL80211_IFTYPE_AP:
1217 	case NL80211_IFTYPE_P2P_GO:
1218 		if (wdev->cac_started) {
1219 			*chan = wdev->chandef.chan;
1220 			*chanmode = CHAN_MODE_SHARED;
1221 			*radar_detect |= BIT(wdev->chandef.width);
1222 		} else if (wdev->beacon_interval) {
1223 			*chan = wdev->chandef.chan;
1224 			*chanmode = CHAN_MODE_SHARED;
1225 
1226 			ret = cfg80211_chandef_dfs_required(wdev->wiphy,
1227 							    &wdev->chandef,
1228 							    wdev->iftype);
1229 			WARN_ON(ret < 0);
1230 			if (ret > 0)
1231 				*radar_detect |= BIT(wdev->chandef.width);
1232 		}
1233 		return;
1234 	case NL80211_IFTYPE_MESH_POINT:
1235 		if (wdev->mesh_id_len) {
1236 			*chan = wdev->chandef.chan;
1237 			*chanmode = CHAN_MODE_SHARED;
1238 
1239 			ret = cfg80211_chandef_dfs_required(wdev->wiphy,
1240 							    &wdev->chandef,
1241 							    wdev->iftype);
1242 			WARN_ON(ret < 0);
1243 			if (ret > 0)
1244 				*radar_detect |= BIT(wdev->chandef.width);
1245 		}
1246 		return;
1247 	case NL80211_IFTYPE_OCB:
1248 		if (wdev->chandef.chan) {
1249 			*chan = wdev->chandef.chan;
1250 			*chanmode = CHAN_MODE_SHARED;
1251 			return;
1252 		}
1253 		break;
1254 	case NL80211_IFTYPE_MONITOR:
1255 	case NL80211_IFTYPE_AP_VLAN:
1256 	case NL80211_IFTYPE_WDS:
1257 	case NL80211_IFTYPE_P2P_DEVICE:
1258 	case NL80211_IFTYPE_NAN:
1259 		/* these interface types don't really have a channel */
1260 		return;
1261 	case NL80211_IFTYPE_UNSPECIFIED:
1262 	case NUM_NL80211_IFTYPES:
1263 		WARN_ON(1);
1264 	}
1265 }
1266