1 /*
2 * This file contains helper code to handle channel
3 * settings and keeping track of what is possible at
4 * any point in time.
5 *
6 * Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
7 * Copyright 2013-2014 Intel Mobile Communications GmbH
8 */
9
10 #include <linux/export.h>
11 #include <net/cfg80211.h>
12 #include "core.h"
13 #include "rdev-ops.h"
14
cfg80211_chandef_create(struct cfg80211_chan_def * chandef,struct ieee80211_channel * chan,enum nl80211_channel_type chan_type)15 void cfg80211_chandef_create(struct cfg80211_chan_def *chandef,
16 struct ieee80211_channel *chan,
17 enum nl80211_channel_type chan_type)
18 {
19 if (WARN_ON(!chan))
20 return;
21
22 chandef->chan = chan;
23 chandef->center_freq2 = 0;
24
25 switch (chan_type) {
26 case NL80211_CHAN_NO_HT:
27 chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
28 chandef->center_freq1 = chan->center_freq;
29 break;
30 case NL80211_CHAN_HT20:
31 chandef->width = NL80211_CHAN_WIDTH_20;
32 chandef->center_freq1 = chan->center_freq;
33 break;
34 case NL80211_CHAN_HT40PLUS:
35 chandef->width = NL80211_CHAN_WIDTH_40;
36 chandef->center_freq1 = chan->center_freq + 10;
37 break;
38 case NL80211_CHAN_HT40MINUS:
39 chandef->width = NL80211_CHAN_WIDTH_40;
40 chandef->center_freq1 = chan->center_freq - 10;
41 break;
42 default:
43 WARN_ON(1);
44 }
45 }
46 EXPORT_SYMBOL(cfg80211_chandef_create);
47
cfg80211_chandef_valid(const struct cfg80211_chan_def * chandef)48 bool cfg80211_chandef_valid(const struct cfg80211_chan_def *chandef)
49 {
50 u32 control_freq;
51
52 if (!chandef->chan)
53 return false;
54
55 control_freq = chandef->chan->center_freq;
56
57 switch (chandef->width) {
58 case NL80211_CHAN_WIDTH_5:
59 case NL80211_CHAN_WIDTH_10:
60 case NL80211_CHAN_WIDTH_20:
61 case NL80211_CHAN_WIDTH_20_NOHT:
62 if (chandef->center_freq1 != control_freq)
63 return false;
64 if (chandef->center_freq2)
65 return false;
66 break;
67 case NL80211_CHAN_WIDTH_40:
68 if (chandef->center_freq1 != control_freq + 10 &&
69 chandef->center_freq1 != control_freq - 10)
70 return false;
71 if (chandef->center_freq2)
72 return false;
73 break;
74 case NL80211_CHAN_WIDTH_80P80:
75 if (chandef->center_freq1 != control_freq + 30 &&
76 chandef->center_freq1 != control_freq + 10 &&
77 chandef->center_freq1 != control_freq - 10 &&
78 chandef->center_freq1 != control_freq - 30)
79 return false;
80 if (!chandef->center_freq2)
81 return false;
82 /* adjacent is not allowed -- that's a 160 MHz channel */
83 if (chandef->center_freq1 - chandef->center_freq2 == 80 ||
84 chandef->center_freq2 - chandef->center_freq1 == 80)
85 return false;
86 break;
87 case NL80211_CHAN_WIDTH_80:
88 if (chandef->center_freq1 != control_freq + 30 &&
89 chandef->center_freq1 != control_freq + 10 &&
90 chandef->center_freq1 != control_freq - 10 &&
91 chandef->center_freq1 != control_freq - 30)
92 return false;
93 if (chandef->center_freq2)
94 return false;
95 break;
96 case NL80211_CHAN_WIDTH_160:
97 if (chandef->center_freq1 != control_freq + 70 &&
98 chandef->center_freq1 != control_freq + 50 &&
99 chandef->center_freq1 != control_freq + 30 &&
100 chandef->center_freq1 != control_freq + 10 &&
101 chandef->center_freq1 != control_freq - 10 &&
102 chandef->center_freq1 != control_freq - 30 &&
103 chandef->center_freq1 != control_freq - 50 &&
104 chandef->center_freq1 != control_freq - 70)
105 return false;
106 if (chandef->center_freq2)
107 return false;
108 break;
109 default:
110 return false;
111 }
112
113 return true;
114 }
115 EXPORT_SYMBOL(cfg80211_chandef_valid);
116
chandef_primary_freqs(const struct cfg80211_chan_def * c,int * pri40,int * pri80)117 static void chandef_primary_freqs(const struct cfg80211_chan_def *c,
118 int *pri40, int *pri80)
119 {
120 int tmp;
121
122 switch (c->width) {
123 case NL80211_CHAN_WIDTH_40:
124 *pri40 = c->center_freq1;
125 *pri80 = 0;
126 break;
127 case NL80211_CHAN_WIDTH_80:
128 case NL80211_CHAN_WIDTH_80P80:
129 *pri80 = c->center_freq1;
130 /* n_P20 */
131 tmp = (30 + c->chan->center_freq - c->center_freq1)/20;
132 /* n_P40 */
133 tmp /= 2;
134 /* freq_P40 */
135 *pri40 = c->center_freq1 - 20 + 40 * tmp;
136 break;
137 case NL80211_CHAN_WIDTH_160:
138 /* n_P20 */
139 tmp = (70 + c->chan->center_freq - c->center_freq1)/20;
140 /* n_P40 */
141 tmp /= 2;
142 /* freq_P40 */
143 *pri40 = c->center_freq1 - 60 + 40 * tmp;
144 /* n_P80 */
145 tmp /= 2;
146 *pri80 = c->center_freq1 - 40 + 80 * tmp;
147 break;
148 default:
149 WARN_ON_ONCE(1);
150 }
151 }
152
cfg80211_chandef_get_width(const struct cfg80211_chan_def * c)153 static int cfg80211_chandef_get_width(const struct cfg80211_chan_def *c)
154 {
155 int width;
156
157 switch (c->width) {
158 case NL80211_CHAN_WIDTH_5:
159 width = 5;
160 break;
161 case NL80211_CHAN_WIDTH_10:
162 width = 10;
163 break;
164 case NL80211_CHAN_WIDTH_20:
165 case NL80211_CHAN_WIDTH_20_NOHT:
166 width = 20;
167 break;
168 case NL80211_CHAN_WIDTH_40:
169 width = 40;
170 break;
171 case NL80211_CHAN_WIDTH_80P80:
172 case NL80211_CHAN_WIDTH_80:
173 width = 80;
174 break;
175 case NL80211_CHAN_WIDTH_160:
176 width = 160;
177 break;
178 default:
179 WARN_ON_ONCE(1);
180 return -1;
181 }
182 return width;
183 }
184
185 const struct cfg80211_chan_def *
cfg80211_chandef_compatible(const struct cfg80211_chan_def * c1,const struct cfg80211_chan_def * c2)186 cfg80211_chandef_compatible(const struct cfg80211_chan_def *c1,
187 const struct cfg80211_chan_def *c2)
188 {
189 u32 c1_pri40, c1_pri80, c2_pri40, c2_pri80;
190
191 /* If they are identical, return */
192 if (cfg80211_chandef_identical(c1, c2))
193 return c1;
194
195 /* otherwise, must have same control channel */
196 if (c1->chan != c2->chan)
197 return NULL;
198
199 /*
200 * If they have the same width, but aren't identical,
201 * then they can't be compatible.
202 */
203 if (c1->width == c2->width)
204 return NULL;
205
206 /*
207 * can't be compatible if one of them is 5 or 10 MHz,
208 * but they don't have the same width.
209 */
210 if (c1->width == NL80211_CHAN_WIDTH_5 ||
211 c1->width == NL80211_CHAN_WIDTH_10 ||
212 c2->width == NL80211_CHAN_WIDTH_5 ||
213 c2->width == NL80211_CHAN_WIDTH_10)
214 return NULL;
215
216 if (c1->width == NL80211_CHAN_WIDTH_20_NOHT ||
217 c1->width == NL80211_CHAN_WIDTH_20)
218 return c2;
219
220 if (c2->width == NL80211_CHAN_WIDTH_20_NOHT ||
221 c2->width == NL80211_CHAN_WIDTH_20)
222 return c1;
223
224 chandef_primary_freqs(c1, &c1_pri40, &c1_pri80);
225 chandef_primary_freqs(c2, &c2_pri40, &c2_pri80);
226
227 if (c1_pri40 != c2_pri40)
228 return NULL;
229
230 WARN_ON(!c1_pri80 && !c2_pri80);
231 if (c1_pri80 && c2_pri80 && c1_pri80 != c2_pri80)
232 return NULL;
233
234 if (c1->width > c2->width)
235 return c1;
236 return c2;
237 }
238 EXPORT_SYMBOL(cfg80211_chandef_compatible);
239
cfg80211_set_chans_dfs_state(struct wiphy * wiphy,u32 center_freq,u32 bandwidth,enum nl80211_dfs_state dfs_state)240 static void cfg80211_set_chans_dfs_state(struct wiphy *wiphy, u32 center_freq,
241 u32 bandwidth,
242 enum nl80211_dfs_state dfs_state)
243 {
244 struct ieee80211_channel *c;
245 u32 freq;
246
247 for (freq = center_freq - bandwidth/2 + 10;
248 freq <= center_freq + bandwidth/2 - 10;
249 freq += 20) {
250 c = ieee80211_get_channel(wiphy, freq);
251 if (!c || !(c->flags & IEEE80211_CHAN_RADAR))
252 continue;
253
254 c->dfs_state = dfs_state;
255 c->dfs_state_entered = jiffies;
256 }
257 }
258
cfg80211_set_dfs_state(struct wiphy * wiphy,const struct cfg80211_chan_def * chandef,enum nl80211_dfs_state dfs_state)259 void cfg80211_set_dfs_state(struct wiphy *wiphy,
260 const struct cfg80211_chan_def *chandef,
261 enum nl80211_dfs_state dfs_state)
262 {
263 int width;
264
265 if (WARN_ON(!cfg80211_chandef_valid(chandef)))
266 return;
267
268 width = cfg80211_chandef_get_width(chandef);
269 if (width < 0)
270 return;
271
272 cfg80211_set_chans_dfs_state(wiphy, chandef->center_freq1,
273 width, dfs_state);
274
275 if (!chandef->center_freq2)
276 return;
277 cfg80211_set_chans_dfs_state(wiphy, chandef->center_freq2,
278 width, dfs_state);
279 }
280
cfg80211_get_start_freq(u32 center_freq,u32 bandwidth)281 static u32 cfg80211_get_start_freq(u32 center_freq,
282 u32 bandwidth)
283 {
284 u32 start_freq;
285
286 if (bandwidth <= 20)
287 start_freq = center_freq;
288 else
289 start_freq = center_freq - bandwidth/2 + 10;
290
291 return start_freq;
292 }
293
cfg80211_get_end_freq(u32 center_freq,u32 bandwidth)294 static u32 cfg80211_get_end_freq(u32 center_freq,
295 u32 bandwidth)
296 {
297 u32 end_freq;
298
299 if (bandwidth <= 20)
300 end_freq = center_freq;
301 else
302 end_freq = center_freq + bandwidth/2 - 10;
303
304 return end_freq;
305 }
306
cfg80211_get_chans_dfs_required(struct wiphy * wiphy,u32 center_freq,u32 bandwidth)307 static int cfg80211_get_chans_dfs_required(struct wiphy *wiphy,
308 u32 center_freq,
309 u32 bandwidth)
310 {
311 struct ieee80211_channel *c;
312 u32 freq, start_freq, end_freq;
313
314 start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
315 end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
316
317 for (freq = start_freq; freq <= end_freq; freq += 20) {
318 c = ieee80211_get_channel(wiphy, freq);
319 if (!c)
320 return -EINVAL;
321
322 if (c->flags & IEEE80211_CHAN_RADAR)
323 return 1;
324 }
325 return 0;
326 }
327
328
cfg80211_chandef_dfs_required(struct wiphy * wiphy,const struct cfg80211_chan_def * chandef,enum nl80211_iftype iftype)329 int cfg80211_chandef_dfs_required(struct wiphy *wiphy,
330 const struct cfg80211_chan_def *chandef,
331 enum nl80211_iftype iftype)
332 {
333 int width;
334 int ret;
335
336 if (WARN_ON(!cfg80211_chandef_valid(chandef)))
337 return -EINVAL;
338
339 switch (iftype) {
340 case NL80211_IFTYPE_ADHOC:
341 case NL80211_IFTYPE_AP:
342 case NL80211_IFTYPE_P2P_GO:
343 case NL80211_IFTYPE_MESH_POINT:
344 width = cfg80211_chandef_get_width(chandef);
345 if (width < 0)
346 return -EINVAL;
347
348 ret = cfg80211_get_chans_dfs_required(wiphy,
349 chandef->center_freq1,
350 width);
351 if (ret < 0)
352 return ret;
353 else if (ret > 0)
354 return BIT(chandef->width);
355
356 if (!chandef->center_freq2)
357 return 0;
358
359 ret = cfg80211_get_chans_dfs_required(wiphy,
360 chandef->center_freq2,
361 width);
362 if (ret < 0)
363 return ret;
364 else if (ret > 0)
365 return BIT(chandef->width);
366
367 break;
368 case NL80211_IFTYPE_STATION:
369 case NL80211_IFTYPE_P2P_CLIENT:
370 case NL80211_IFTYPE_MONITOR:
371 case NL80211_IFTYPE_AP_VLAN:
372 case NL80211_IFTYPE_WDS:
373 case NL80211_IFTYPE_P2P_DEVICE:
374 break;
375 case NL80211_IFTYPE_UNSPECIFIED:
376 case NUM_NL80211_IFTYPES:
377 WARN_ON(1);
378 }
379
380 return 0;
381 }
382 EXPORT_SYMBOL(cfg80211_chandef_dfs_required);
383
cfg80211_get_chans_dfs_usable(struct wiphy * wiphy,u32 center_freq,u32 bandwidth)384 static int cfg80211_get_chans_dfs_usable(struct wiphy *wiphy,
385 u32 center_freq,
386 u32 bandwidth)
387 {
388 struct ieee80211_channel *c;
389 u32 freq, start_freq, end_freq;
390 int count = 0;
391
392 start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
393 end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
394
395 /*
396 * Check entire range of channels for the bandwidth.
397 * Check all channels are DFS channels (DFS_USABLE or
398 * DFS_AVAILABLE). Return number of usable channels
399 * (require CAC). Allow DFS and non-DFS channel mix.
400 */
401 for (freq = start_freq; freq <= end_freq; freq += 20) {
402 c = ieee80211_get_channel(wiphy, freq);
403 if (!c)
404 return -EINVAL;
405
406 if (c->flags & IEEE80211_CHAN_DISABLED)
407 return -EINVAL;
408
409 if (c->flags & IEEE80211_CHAN_RADAR) {
410 if (c->dfs_state == NL80211_DFS_UNAVAILABLE)
411 return -EINVAL;
412
413 if (c->dfs_state == NL80211_DFS_USABLE)
414 count++;
415 }
416 }
417
418 return count;
419 }
420
cfg80211_chandef_dfs_usable(struct wiphy * wiphy,const struct cfg80211_chan_def * chandef)421 bool cfg80211_chandef_dfs_usable(struct wiphy *wiphy,
422 const struct cfg80211_chan_def *chandef)
423 {
424 int width;
425 int r1, r2 = 0;
426
427 if (WARN_ON(!cfg80211_chandef_valid(chandef)))
428 return false;
429
430 width = cfg80211_chandef_get_width(chandef);
431 if (width < 0)
432 return false;
433
434 r1 = cfg80211_get_chans_dfs_usable(wiphy, chandef->center_freq1,
435 width);
436
437 if (r1 < 0)
438 return false;
439
440 switch (chandef->width) {
441 case NL80211_CHAN_WIDTH_80P80:
442 WARN_ON(!chandef->center_freq2);
443 r2 = cfg80211_get_chans_dfs_usable(wiphy,
444 chandef->center_freq2,
445 width);
446 if (r2 < 0)
447 return false;
448 break;
449 default:
450 WARN_ON(chandef->center_freq2);
451 break;
452 }
453
454 return (r1 + r2 > 0);
455 }
456
457
cfg80211_get_chans_dfs_available(struct wiphy * wiphy,u32 center_freq,u32 bandwidth)458 static bool cfg80211_get_chans_dfs_available(struct wiphy *wiphy,
459 u32 center_freq,
460 u32 bandwidth)
461 {
462 struct ieee80211_channel *c;
463 u32 freq, start_freq, end_freq;
464
465 start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
466 end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
467
468 /*
469 * Check entire range of channels for the bandwidth.
470 * If any channel in between is disabled or has not
471 * had gone through CAC return false
472 */
473 for (freq = start_freq; freq <= end_freq; freq += 20) {
474 c = ieee80211_get_channel(wiphy, freq);
475 if (!c)
476 return false;
477
478 if (c->flags & IEEE80211_CHAN_DISABLED)
479 return false;
480
481 if ((c->flags & IEEE80211_CHAN_RADAR) &&
482 (c->dfs_state != NL80211_DFS_AVAILABLE))
483 return false;
484 }
485
486 return true;
487 }
488
cfg80211_chandef_dfs_available(struct wiphy * wiphy,const struct cfg80211_chan_def * chandef)489 static bool cfg80211_chandef_dfs_available(struct wiphy *wiphy,
490 const struct cfg80211_chan_def *chandef)
491 {
492 int width;
493 int r;
494
495 if (WARN_ON(!cfg80211_chandef_valid(chandef)))
496 return false;
497
498 width = cfg80211_chandef_get_width(chandef);
499 if (width < 0)
500 return false;
501
502 r = cfg80211_get_chans_dfs_available(wiphy, chandef->center_freq1,
503 width);
504
505 /* If any of channels unavailable for cf1 just return */
506 if (!r)
507 return r;
508
509 switch (chandef->width) {
510 case NL80211_CHAN_WIDTH_80P80:
511 WARN_ON(!chandef->center_freq2);
512 r = cfg80211_get_chans_dfs_available(wiphy,
513 chandef->center_freq2,
514 width);
515 default:
516 WARN_ON(chandef->center_freq2);
517 break;
518 }
519
520 return r;
521 }
522
cfg80211_get_chans_dfs_cac_time(struct wiphy * wiphy,u32 center_freq,u32 bandwidth)523 static unsigned int cfg80211_get_chans_dfs_cac_time(struct wiphy *wiphy,
524 u32 center_freq,
525 u32 bandwidth)
526 {
527 struct ieee80211_channel *c;
528 u32 start_freq, end_freq, freq;
529 unsigned int dfs_cac_ms = 0;
530
531 start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
532 end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
533
534 for (freq = start_freq; freq <= end_freq; freq += 20) {
535 c = ieee80211_get_channel(wiphy, freq);
536 if (!c)
537 return 0;
538
539 if (c->flags & IEEE80211_CHAN_DISABLED)
540 return 0;
541
542 if (!(c->flags & IEEE80211_CHAN_RADAR))
543 continue;
544
545 if (c->dfs_cac_ms > dfs_cac_ms)
546 dfs_cac_ms = c->dfs_cac_ms;
547 }
548
549 return dfs_cac_ms;
550 }
551
552 unsigned int
cfg80211_chandef_dfs_cac_time(struct wiphy * wiphy,const struct cfg80211_chan_def * chandef)553 cfg80211_chandef_dfs_cac_time(struct wiphy *wiphy,
554 const struct cfg80211_chan_def *chandef)
555 {
556 int width;
557 unsigned int t1 = 0, t2 = 0;
558
559 if (WARN_ON(!cfg80211_chandef_valid(chandef)))
560 return 0;
561
562 width = cfg80211_chandef_get_width(chandef);
563 if (width < 0)
564 return 0;
565
566 t1 = cfg80211_get_chans_dfs_cac_time(wiphy,
567 chandef->center_freq1,
568 width);
569
570 if (!chandef->center_freq2)
571 return t1;
572
573 t2 = cfg80211_get_chans_dfs_cac_time(wiphy,
574 chandef->center_freq2,
575 width);
576
577 return max(t1, t2);
578 }
579
cfg80211_secondary_chans_ok(struct wiphy * wiphy,u32 center_freq,u32 bandwidth,u32 prohibited_flags)580 static bool cfg80211_secondary_chans_ok(struct wiphy *wiphy,
581 u32 center_freq, u32 bandwidth,
582 u32 prohibited_flags)
583 {
584 struct ieee80211_channel *c;
585 u32 freq, start_freq, end_freq;
586
587 start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
588 end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
589
590 for (freq = start_freq; freq <= end_freq; freq += 20) {
591 c = ieee80211_get_channel(wiphy, freq);
592 if (!c || c->flags & prohibited_flags)
593 return false;
594 }
595
596 return true;
597 }
598
cfg80211_chandef_usable(struct wiphy * wiphy,const struct cfg80211_chan_def * chandef,u32 prohibited_flags)599 bool cfg80211_chandef_usable(struct wiphy *wiphy,
600 const struct cfg80211_chan_def *chandef,
601 u32 prohibited_flags)
602 {
603 struct ieee80211_sta_ht_cap *ht_cap;
604 struct ieee80211_sta_vht_cap *vht_cap;
605 u32 width, control_freq, cap;
606
607 if (WARN_ON(!cfg80211_chandef_valid(chandef)))
608 return false;
609
610 ht_cap = &wiphy->bands[chandef->chan->band]->ht_cap;
611 vht_cap = &wiphy->bands[chandef->chan->band]->vht_cap;
612
613 control_freq = chandef->chan->center_freq;
614
615 switch (chandef->width) {
616 case NL80211_CHAN_WIDTH_5:
617 width = 5;
618 break;
619 case NL80211_CHAN_WIDTH_10:
620 prohibited_flags |= IEEE80211_CHAN_NO_10MHZ;
621 width = 10;
622 break;
623 case NL80211_CHAN_WIDTH_20:
624 if (!ht_cap->ht_supported)
625 return false;
626 case NL80211_CHAN_WIDTH_20_NOHT:
627 prohibited_flags |= IEEE80211_CHAN_NO_20MHZ;
628 width = 20;
629 break;
630 case NL80211_CHAN_WIDTH_40:
631 width = 40;
632 if (!ht_cap->ht_supported)
633 return false;
634 if (!(ht_cap->cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) ||
635 ht_cap->cap & IEEE80211_HT_CAP_40MHZ_INTOLERANT)
636 return false;
637 if (chandef->center_freq1 < control_freq &&
638 chandef->chan->flags & IEEE80211_CHAN_NO_HT40MINUS)
639 return false;
640 if (chandef->center_freq1 > control_freq &&
641 chandef->chan->flags & IEEE80211_CHAN_NO_HT40PLUS)
642 return false;
643 break;
644 case NL80211_CHAN_WIDTH_80P80:
645 cap = vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
646 if (cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
647 return false;
648 case NL80211_CHAN_WIDTH_80:
649 if (!vht_cap->vht_supported)
650 return false;
651 prohibited_flags |= IEEE80211_CHAN_NO_80MHZ;
652 width = 80;
653 break;
654 case NL80211_CHAN_WIDTH_160:
655 if (!vht_cap->vht_supported)
656 return false;
657 cap = vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
658 if (cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ &&
659 cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
660 return false;
661 prohibited_flags |= IEEE80211_CHAN_NO_160MHZ;
662 width = 160;
663 break;
664 default:
665 WARN_ON_ONCE(1);
666 return false;
667 }
668
669 /*
670 * TODO: What if there are only certain 80/160/80+80 MHz channels
671 * allowed by the driver, or only certain combinations?
672 * For 40 MHz the driver can set the NO_HT40 flags, but for
673 * 80/160 MHz and in particular 80+80 MHz this isn't really
674 * feasible and we only have NO_80MHZ/NO_160MHZ so far but
675 * no way to cover 80+80 MHz or more complex restrictions.
676 * Note that such restrictions also need to be advertised to
677 * userspace, for example for P2P channel selection.
678 */
679
680 if (width > 20)
681 prohibited_flags |= IEEE80211_CHAN_NO_OFDM;
682
683 /* 5 and 10 MHz are only defined for the OFDM PHY */
684 if (width < 20)
685 prohibited_flags |= IEEE80211_CHAN_NO_OFDM;
686
687
688 if (!cfg80211_secondary_chans_ok(wiphy, chandef->center_freq1,
689 width, prohibited_flags))
690 return false;
691
692 if (!chandef->center_freq2)
693 return true;
694 return cfg80211_secondary_chans_ok(wiphy, chandef->center_freq2,
695 width, prohibited_flags);
696 }
697 EXPORT_SYMBOL(cfg80211_chandef_usable);
698
699 /*
700 * For GO only, check if the channel can be used under permissive conditions
701 * mandated by the some regulatory bodies, i.e., the channel is marked with
702 * IEEE80211_CHAN_GO_CONCURRENT and there is an additional station interface
703 * associated to an AP on the same channel or on the same UNII band
704 * (assuming that the AP is an authorized master).
705 * In addition allow the GO to operate on a channel on which indoor operation is
706 * allowed, iff we are currently operating in an indoor environment.
707 */
cfg80211_go_permissive_chan(struct cfg80211_registered_device * rdev,struct ieee80211_channel * chan)708 static bool cfg80211_go_permissive_chan(struct cfg80211_registered_device *rdev,
709 struct ieee80211_channel *chan)
710 {
711 struct wireless_dev *wdev_iter;
712 struct wiphy *wiphy = wiphy_idx_to_wiphy(rdev->wiphy_idx);
713
714 ASSERT_RTNL();
715
716 if (!config_enabled(CONFIG_CFG80211_REG_RELAX_NO_IR) ||
717 !(wiphy->regulatory_flags & REGULATORY_ENABLE_RELAX_NO_IR))
718 return false;
719
720 if (regulatory_indoor_allowed() &&
721 (chan->flags & IEEE80211_CHAN_INDOOR_ONLY))
722 return true;
723
724 if (!(chan->flags & IEEE80211_CHAN_GO_CONCURRENT))
725 return false;
726
727 /*
728 * Generally, it is possible to rely on another device/driver to allow
729 * the GO concurrent relaxation, however, since the device can further
730 * enforce the relaxation (by doing a similar verifications as this),
731 * and thus fail the GO instantiation, consider only the interfaces of
732 * the current registered device.
733 */
734 list_for_each_entry(wdev_iter, &rdev->wdev_list, list) {
735 struct ieee80211_channel *other_chan = NULL;
736 int r1, r2;
737
738 if (wdev_iter->iftype != NL80211_IFTYPE_STATION ||
739 !netif_running(wdev_iter->netdev))
740 continue;
741
742 wdev_lock(wdev_iter);
743 if (wdev_iter->current_bss)
744 other_chan = wdev_iter->current_bss->pub.channel;
745 wdev_unlock(wdev_iter);
746
747 if (!other_chan)
748 continue;
749
750 if (chan == other_chan)
751 return true;
752
753 if (chan->band != IEEE80211_BAND_5GHZ)
754 continue;
755
756 r1 = cfg80211_get_unii(chan->center_freq);
757 r2 = cfg80211_get_unii(other_chan->center_freq);
758
759 if (r1 != -EINVAL && r1 == r2) {
760 /*
761 * At some locations channels 149-165 are considered a
762 * bundle, but at other locations, e.g., Indonesia,
763 * channels 149-161 are considered a bundle while
764 * channel 165 is left out and considered to be in a
765 * different bundle. Thus, in case that there is a
766 * station interface connected to an AP on channel 165,
767 * it is assumed that channels 149-161 are allowed for
768 * GO operations. However, having a station interface
769 * connected to an AP on channels 149-161, does not
770 * allow GO operation on channel 165.
771 */
772 if (chan->center_freq == 5825 &&
773 other_chan->center_freq != 5825)
774 continue;
775 return true;
776 }
777 }
778
779 return false;
780 }
781
cfg80211_reg_can_beacon(struct wiphy * wiphy,struct cfg80211_chan_def * chandef,enum nl80211_iftype iftype)782 bool cfg80211_reg_can_beacon(struct wiphy *wiphy,
783 struct cfg80211_chan_def *chandef,
784 enum nl80211_iftype iftype)
785 {
786 struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
787 bool res;
788 u32 prohibited_flags = IEEE80211_CHAN_DISABLED |
789 IEEE80211_CHAN_RADAR;
790
791 trace_cfg80211_reg_can_beacon(wiphy, chandef, iftype);
792
793 /*
794 * Under certain conditions suggested by the some regulatory bodies
795 * a GO can operate on channels marked with IEEE80211_NO_IR
796 * so set this flag only if such relaxations are not enabled and
797 * the conditions are not met.
798 */
799 if (iftype != NL80211_IFTYPE_P2P_GO ||
800 !cfg80211_go_permissive_chan(rdev, chandef->chan))
801 prohibited_flags |= IEEE80211_CHAN_NO_IR;
802
803 if (cfg80211_chandef_dfs_required(wiphy, chandef, iftype) > 0 &&
804 cfg80211_chandef_dfs_available(wiphy, chandef)) {
805 /* We can skip IEEE80211_CHAN_NO_IR if chandef dfs available */
806 prohibited_flags = IEEE80211_CHAN_DISABLED;
807 }
808
809 res = cfg80211_chandef_usable(wiphy, chandef, prohibited_flags);
810
811 trace_cfg80211_return_bool(res);
812 return res;
813 }
814 EXPORT_SYMBOL(cfg80211_reg_can_beacon);
815
cfg80211_set_monitor_channel(struct cfg80211_registered_device * rdev,struct cfg80211_chan_def * chandef)816 int cfg80211_set_monitor_channel(struct cfg80211_registered_device *rdev,
817 struct cfg80211_chan_def *chandef)
818 {
819 if (!rdev->ops->set_monitor_channel)
820 return -EOPNOTSUPP;
821 if (!cfg80211_has_monitors_only(rdev))
822 return -EBUSY;
823
824 return rdev_set_monitor_channel(rdev, chandef);
825 }
826
827 void
cfg80211_get_chan_state(struct wireless_dev * wdev,struct ieee80211_channel ** chan,enum cfg80211_chan_mode * chanmode,u8 * radar_detect)828 cfg80211_get_chan_state(struct wireless_dev *wdev,
829 struct ieee80211_channel **chan,
830 enum cfg80211_chan_mode *chanmode,
831 u8 *radar_detect)
832 {
833 int ret;
834
835 *chan = NULL;
836 *chanmode = CHAN_MODE_UNDEFINED;
837
838 ASSERT_WDEV_LOCK(wdev);
839
840 if (wdev->netdev && !netif_running(wdev->netdev))
841 return;
842
843 switch (wdev->iftype) {
844 case NL80211_IFTYPE_ADHOC:
845 if (wdev->current_bss) {
846 *chan = wdev->current_bss->pub.channel;
847 *chanmode = (wdev->ibss_fixed &&
848 !wdev->ibss_dfs_possible)
849 ? CHAN_MODE_SHARED
850 : CHAN_MODE_EXCLUSIVE;
851
852 /* consider worst-case - IBSS can try to return to the
853 * original user-specified channel as creator */
854 if (wdev->ibss_dfs_possible)
855 *radar_detect |= BIT(wdev->chandef.width);
856 return;
857 }
858 break;
859 case NL80211_IFTYPE_STATION:
860 case NL80211_IFTYPE_P2P_CLIENT:
861 if (wdev->current_bss) {
862 *chan = wdev->current_bss->pub.channel;
863 *chanmode = CHAN_MODE_SHARED;
864 return;
865 }
866 break;
867 case NL80211_IFTYPE_AP:
868 case NL80211_IFTYPE_P2P_GO:
869 if (wdev->cac_started) {
870 *chan = wdev->chandef.chan;
871 *chanmode = CHAN_MODE_SHARED;
872 *radar_detect |= BIT(wdev->chandef.width);
873 } else if (wdev->beacon_interval) {
874 *chan = wdev->chandef.chan;
875 *chanmode = CHAN_MODE_SHARED;
876
877 ret = cfg80211_chandef_dfs_required(wdev->wiphy,
878 &wdev->chandef,
879 wdev->iftype);
880 WARN_ON(ret < 0);
881 if (ret > 0)
882 *radar_detect |= BIT(wdev->chandef.width);
883 }
884 return;
885 case NL80211_IFTYPE_MESH_POINT:
886 if (wdev->mesh_id_len) {
887 *chan = wdev->chandef.chan;
888 *chanmode = CHAN_MODE_SHARED;
889
890 ret = cfg80211_chandef_dfs_required(wdev->wiphy,
891 &wdev->chandef,
892 wdev->iftype);
893 WARN_ON(ret < 0);
894 if (ret > 0)
895 *radar_detect |= BIT(wdev->chandef.width);
896 }
897 return;
898 case NL80211_IFTYPE_MONITOR:
899 case NL80211_IFTYPE_AP_VLAN:
900 case NL80211_IFTYPE_WDS:
901 case NL80211_IFTYPE_P2P_DEVICE:
902 /* these interface types don't really have a channel */
903 return;
904 case NL80211_IFTYPE_UNSPECIFIED:
905 case NUM_NL80211_IFTYPES:
906 WARN_ON(1);
907 }
908 }
909