Merge remote-tracking branches 'spi/topic/rspi', 'spi/topic/sc18is602', 'spi/topic...
[cascardo/linux.git] / net / wireless / chan.c
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
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
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
117 static void chandef_primary_freqs(const struct cfg80211_chan_def *c,
118                                   u32 *pri40, u32 *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
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 *
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
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
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
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
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
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
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_OCB:
370         case NL80211_IFTYPE_P2P_CLIENT:
371         case NL80211_IFTYPE_MONITOR:
372         case NL80211_IFTYPE_AP_VLAN:
373         case NL80211_IFTYPE_WDS:
374         case NL80211_IFTYPE_P2P_DEVICE:
375                 break;
376         case NL80211_IFTYPE_UNSPECIFIED:
377         case NUM_NL80211_IFTYPES:
378                 WARN_ON(1);
379         }
380
381         return 0;
382 }
383 EXPORT_SYMBOL(cfg80211_chandef_dfs_required);
384
385 static int cfg80211_get_chans_dfs_usable(struct wiphy *wiphy,
386                                          u32 center_freq,
387                                          u32 bandwidth)
388 {
389         struct ieee80211_channel *c;
390         u32 freq, start_freq, end_freq;
391         int count = 0;
392
393         start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
394         end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
395
396         /*
397          * Check entire range of channels for the bandwidth.
398          * Check all channels are DFS channels (DFS_USABLE or
399          * DFS_AVAILABLE). Return number of usable channels
400          * (require CAC). Allow DFS and non-DFS channel mix.
401          */
402         for (freq = start_freq; freq <= end_freq; freq += 20) {
403                 c = ieee80211_get_channel(wiphy, freq);
404                 if (!c)
405                         return -EINVAL;
406
407                 if (c->flags & IEEE80211_CHAN_DISABLED)
408                         return -EINVAL;
409
410                 if (c->flags & IEEE80211_CHAN_RADAR) {
411                         if (c->dfs_state == NL80211_DFS_UNAVAILABLE)
412                                 return -EINVAL;
413
414                         if (c->dfs_state == NL80211_DFS_USABLE)
415                                 count++;
416                 }
417         }
418
419         return count;
420 }
421
422 bool cfg80211_chandef_dfs_usable(struct wiphy *wiphy,
423                                  const struct cfg80211_chan_def *chandef)
424 {
425         int width;
426         int r1, r2 = 0;
427
428         if (WARN_ON(!cfg80211_chandef_valid(chandef)))
429                 return false;
430
431         width = cfg80211_chandef_get_width(chandef);
432         if (width < 0)
433                 return false;
434
435         r1 = cfg80211_get_chans_dfs_usable(wiphy, chandef->center_freq1,
436                                           width);
437
438         if (r1 < 0)
439                 return false;
440
441         switch (chandef->width) {
442         case NL80211_CHAN_WIDTH_80P80:
443                 WARN_ON(!chandef->center_freq2);
444                 r2 = cfg80211_get_chans_dfs_usable(wiphy,
445                                                    chandef->center_freq2,
446                                                    width);
447                 if (r2 < 0)
448                         return false;
449                 break;
450         default:
451                 WARN_ON(chandef->center_freq2);
452                 break;
453         }
454
455         return (r1 + r2 > 0);
456 }
457
458
459 static bool cfg80211_get_chans_dfs_available(struct wiphy *wiphy,
460                                              u32 center_freq,
461                                              u32 bandwidth)
462 {
463         struct ieee80211_channel *c;
464         u32 freq, start_freq, end_freq;
465
466         start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
467         end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
468
469         /*
470          * Check entire range of channels for the bandwidth.
471          * If any channel in between is disabled or has not
472          * had gone through CAC return false
473          */
474         for (freq = start_freq; freq <= end_freq; freq += 20) {
475                 c = ieee80211_get_channel(wiphy, freq);
476                 if (!c)
477                         return false;
478
479                 if (c->flags & IEEE80211_CHAN_DISABLED)
480                         return false;
481
482                 if ((c->flags & IEEE80211_CHAN_RADAR)  &&
483                     (c->dfs_state != NL80211_DFS_AVAILABLE))
484                         return false;
485         }
486
487         return true;
488 }
489
490 static bool cfg80211_chandef_dfs_available(struct wiphy *wiphy,
491                                 const struct cfg80211_chan_def *chandef)
492 {
493         int width;
494         int r;
495
496         if (WARN_ON(!cfg80211_chandef_valid(chandef)))
497                 return false;
498
499         width = cfg80211_chandef_get_width(chandef);
500         if (width < 0)
501                 return false;
502
503         r = cfg80211_get_chans_dfs_available(wiphy, chandef->center_freq1,
504                                              width);
505
506         /* If any of channels unavailable for cf1 just return */
507         if (!r)
508                 return r;
509
510         switch (chandef->width) {
511         case NL80211_CHAN_WIDTH_80P80:
512                 WARN_ON(!chandef->center_freq2);
513                 r = cfg80211_get_chans_dfs_available(wiphy,
514                                                      chandef->center_freq2,
515                                                      width);
516                 break;
517         default:
518                 WARN_ON(chandef->center_freq2);
519                 break;
520         }
521
522         return r;
523 }
524
525 static unsigned int cfg80211_get_chans_dfs_cac_time(struct wiphy *wiphy,
526                                                     u32 center_freq,
527                                                     u32 bandwidth)
528 {
529         struct ieee80211_channel *c;
530         u32 start_freq, end_freq, freq;
531         unsigned int dfs_cac_ms = 0;
532
533         start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
534         end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
535
536         for (freq = start_freq; freq <= end_freq; freq += 20) {
537                 c = ieee80211_get_channel(wiphy, freq);
538                 if (!c)
539                         return 0;
540
541                 if (c->flags & IEEE80211_CHAN_DISABLED)
542                         return 0;
543
544                 if (!(c->flags & IEEE80211_CHAN_RADAR))
545                         continue;
546
547                 if (c->dfs_cac_ms > dfs_cac_ms)
548                         dfs_cac_ms = c->dfs_cac_ms;
549         }
550
551         return dfs_cac_ms;
552 }
553
554 unsigned int
555 cfg80211_chandef_dfs_cac_time(struct wiphy *wiphy,
556                               const struct cfg80211_chan_def *chandef)
557 {
558         int width;
559         unsigned int t1 = 0, t2 = 0;
560
561         if (WARN_ON(!cfg80211_chandef_valid(chandef)))
562                 return 0;
563
564         width = cfg80211_chandef_get_width(chandef);
565         if (width < 0)
566                 return 0;
567
568         t1 = cfg80211_get_chans_dfs_cac_time(wiphy,
569                                              chandef->center_freq1,
570                                              width);
571
572         if (!chandef->center_freq2)
573                 return t1;
574
575         t2 = cfg80211_get_chans_dfs_cac_time(wiphy,
576                                              chandef->center_freq2,
577                                              width);
578
579         return max(t1, t2);
580 }
581
582 static bool cfg80211_secondary_chans_ok(struct wiphy *wiphy,
583                                         u32 center_freq, u32 bandwidth,
584                                         u32 prohibited_flags)
585 {
586         struct ieee80211_channel *c;
587         u32 freq, start_freq, end_freq;
588
589         start_freq = cfg80211_get_start_freq(center_freq, bandwidth);
590         end_freq = cfg80211_get_end_freq(center_freq, bandwidth);
591
592         for (freq = start_freq; freq <= end_freq; freq += 20) {
593                 c = ieee80211_get_channel(wiphy, freq);
594                 if (!c || c->flags & prohibited_flags)
595                         return false;
596         }
597
598         return true;
599 }
600
601 bool cfg80211_chandef_usable(struct wiphy *wiphy,
602                              const struct cfg80211_chan_def *chandef,
603                              u32 prohibited_flags)
604 {
605         struct ieee80211_sta_ht_cap *ht_cap;
606         struct ieee80211_sta_vht_cap *vht_cap;
607         u32 width, control_freq, cap;
608
609         if (WARN_ON(!cfg80211_chandef_valid(chandef)))
610                 return false;
611
612         ht_cap = &wiphy->bands[chandef->chan->band]->ht_cap;
613         vht_cap = &wiphy->bands[chandef->chan->band]->vht_cap;
614
615         control_freq = chandef->chan->center_freq;
616
617         switch (chandef->width) {
618         case NL80211_CHAN_WIDTH_5:
619                 width = 5;
620                 break;
621         case NL80211_CHAN_WIDTH_10:
622                 prohibited_flags |= IEEE80211_CHAN_NO_10MHZ;
623                 width = 10;
624                 break;
625         case NL80211_CHAN_WIDTH_20:
626                 if (!ht_cap->ht_supported)
627                         return false;
628         case NL80211_CHAN_WIDTH_20_NOHT:
629                 prohibited_flags |= IEEE80211_CHAN_NO_20MHZ;
630                 width = 20;
631                 break;
632         case NL80211_CHAN_WIDTH_40:
633                 width = 40;
634                 if (!ht_cap->ht_supported)
635                         return false;
636                 if (!(ht_cap->cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) ||
637                     ht_cap->cap & IEEE80211_HT_CAP_40MHZ_INTOLERANT)
638                         return false;
639                 if (chandef->center_freq1 < control_freq &&
640                     chandef->chan->flags & IEEE80211_CHAN_NO_HT40MINUS)
641                         return false;
642                 if (chandef->center_freq1 > control_freq &&
643                     chandef->chan->flags & IEEE80211_CHAN_NO_HT40PLUS)
644                         return false;
645                 break;
646         case NL80211_CHAN_WIDTH_80P80:
647                 cap = vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
648                 if (cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
649                         return false;
650         case NL80211_CHAN_WIDTH_80:
651                 if (!vht_cap->vht_supported)
652                         return false;
653                 prohibited_flags |= IEEE80211_CHAN_NO_80MHZ;
654                 width = 80;
655                 break;
656         case NL80211_CHAN_WIDTH_160:
657                 if (!vht_cap->vht_supported)
658                         return false;
659                 cap = vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
660                 if (cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ &&
661                     cap != IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
662                         return false;
663                 prohibited_flags |= IEEE80211_CHAN_NO_160MHZ;
664                 width = 160;
665                 break;
666         default:
667                 WARN_ON_ONCE(1);
668                 return false;
669         }
670
671         /*
672          * TODO: What if there are only certain 80/160/80+80 MHz channels
673          *       allowed by the driver, or only certain combinations?
674          *       For 40 MHz the driver can set the NO_HT40 flags, but for
675          *       80/160 MHz and in particular 80+80 MHz this isn't really
676          *       feasible and we only have NO_80MHZ/NO_160MHZ so far but
677          *       no way to cover 80+80 MHz or more complex restrictions.
678          *       Note that such restrictions also need to be advertised to
679          *       userspace, for example for P2P channel selection.
680          */
681
682         if (width > 20)
683                 prohibited_flags |= IEEE80211_CHAN_NO_OFDM;
684
685         /* 5 and 10 MHz are only defined for the OFDM PHY */
686         if (width < 20)
687                 prohibited_flags |= IEEE80211_CHAN_NO_OFDM;
688
689
690         if (!cfg80211_secondary_chans_ok(wiphy, chandef->center_freq1,
691                                          width, prohibited_flags))
692                 return false;
693
694         if (!chandef->center_freq2)
695                 return true;
696         return cfg80211_secondary_chans_ok(wiphy, chandef->center_freq2,
697                                            width, prohibited_flags);
698 }
699 EXPORT_SYMBOL(cfg80211_chandef_usable);
700
701 /*
702  * Check if the channel can be used under permissive conditions mandated by
703  * some regulatory bodies, i.e., the channel is marked with
704  * IEEE80211_CHAN_IR_CONCURRENT and there is an additional station interface
705  * associated to an AP on the same channel or on the same UNII band
706  * (assuming that the AP is an authorized master).
707  * In addition allow operation on a channel on which indoor operation is
708  * allowed, iff we are currently operating in an indoor environment.
709  */
710 static bool cfg80211_ir_permissive_chan(struct wiphy *wiphy,
711                                         enum nl80211_iftype iftype,
712                                         struct ieee80211_channel *chan)
713 {
714         struct wireless_dev *wdev;
715         struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
716
717         ASSERT_RTNL();
718
719         if (!IS_ENABLED(CONFIG_CFG80211_REG_RELAX_NO_IR) ||
720             !(wiphy->regulatory_flags & REGULATORY_ENABLE_RELAX_NO_IR))
721                 return false;
722
723         /* only valid for GO and TDLS off-channel (station/p2p-CL) */
724         if (iftype != NL80211_IFTYPE_P2P_GO &&
725             iftype != NL80211_IFTYPE_STATION &&
726             iftype != NL80211_IFTYPE_P2P_CLIENT)
727                 return false;
728
729         if (regulatory_indoor_allowed() &&
730             (chan->flags & IEEE80211_CHAN_INDOOR_ONLY))
731                 return true;
732
733         if (!(chan->flags & IEEE80211_CHAN_IR_CONCURRENT))
734                 return false;
735
736         /*
737          * Generally, it is possible to rely on another device/driver to allow
738          * the IR concurrent relaxation, however, since the device can further
739          * enforce the relaxation (by doing a similar verifications as this),
740          * and thus fail the GO instantiation, consider only the interfaces of
741          * the current registered device.
742          */
743         list_for_each_entry(wdev, &rdev->wiphy.wdev_list, list) {
744                 struct ieee80211_channel *other_chan = NULL;
745                 int r1, r2;
746
747                 wdev_lock(wdev);
748                 if (wdev->iftype == NL80211_IFTYPE_STATION &&
749                     wdev->current_bss)
750                         other_chan = wdev->current_bss->pub.channel;
751
752                 /*
753                  * If a GO already operates on the same GO_CONCURRENT channel,
754                  * this one (maybe the same one) can beacon as well. We allow
755                  * the operation even if the station we relied on with
756                  * GO_CONCURRENT is disconnected now. But then we must make sure
757                  * we're not outdoor on an indoor-only channel.
758                  */
759                 if (iftype == NL80211_IFTYPE_P2P_GO &&
760                     wdev->iftype == NL80211_IFTYPE_P2P_GO &&
761                     wdev->beacon_interval &&
762                     !(chan->flags & IEEE80211_CHAN_INDOOR_ONLY))
763                         other_chan = wdev->chandef.chan;
764                 wdev_unlock(wdev);
765
766                 if (!other_chan)
767                         continue;
768
769                 if (chan == other_chan)
770                         return true;
771
772                 if (chan->band != NL80211_BAND_5GHZ)
773                         continue;
774
775                 r1 = cfg80211_get_unii(chan->center_freq);
776                 r2 = cfg80211_get_unii(other_chan->center_freq);
777
778                 if (r1 != -EINVAL && r1 == r2) {
779                         /*
780                          * At some locations channels 149-165 are considered a
781                          * bundle, but at other locations, e.g., Indonesia,
782                          * channels 149-161 are considered a bundle while
783                          * channel 165 is left out and considered to be in a
784                          * different bundle. Thus, in case that there is a
785                          * station interface connected to an AP on channel 165,
786                          * it is assumed that channels 149-161 are allowed for
787                          * GO operations. However, having a station interface
788                          * connected to an AP on channels 149-161, does not
789                          * allow GO operation on channel 165.
790                          */
791                         if (chan->center_freq == 5825 &&
792                             other_chan->center_freq != 5825)
793                                 continue;
794                         return true;
795                 }
796         }
797
798         return false;
799 }
800
801 static bool _cfg80211_reg_can_beacon(struct wiphy *wiphy,
802                                      struct cfg80211_chan_def *chandef,
803                                      enum nl80211_iftype iftype,
804                                      bool check_no_ir)
805 {
806         bool res;
807         u32 prohibited_flags = IEEE80211_CHAN_DISABLED |
808                                IEEE80211_CHAN_RADAR;
809
810         trace_cfg80211_reg_can_beacon(wiphy, chandef, iftype, check_no_ir);
811
812         if (check_no_ir)
813                 prohibited_flags |= IEEE80211_CHAN_NO_IR;
814
815         if (cfg80211_chandef_dfs_required(wiphy, chandef, iftype) > 0 &&
816             cfg80211_chandef_dfs_available(wiphy, chandef)) {
817                 /* We can skip IEEE80211_CHAN_NO_IR if chandef dfs available */
818                 prohibited_flags = IEEE80211_CHAN_DISABLED;
819         }
820
821         res = cfg80211_chandef_usable(wiphy, chandef, prohibited_flags);
822
823         trace_cfg80211_return_bool(res);
824         return res;
825 }
826
827 bool cfg80211_reg_can_beacon(struct wiphy *wiphy,
828                              struct cfg80211_chan_def *chandef,
829                              enum nl80211_iftype iftype)
830 {
831         return _cfg80211_reg_can_beacon(wiphy, chandef, iftype, true);
832 }
833 EXPORT_SYMBOL(cfg80211_reg_can_beacon);
834
835 bool cfg80211_reg_can_beacon_relax(struct wiphy *wiphy,
836                                    struct cfg80211_chan_def *chandef,
837                                    enum nl80211_iftype iftype)
838 {
839         bool check_no_ir;
840
841         ASSERT_RTNL();
842
843         /*
844          * Under certain conditions suggested by some regulatory bodies a
845          * GO/STA can IR on channels marked with IEEE80211_NO_IR. Set this flag
846          * only if such relaxations are not enabled and the conditions are not
847          * met.
848          */
849         check_no_ir = !cfg80211_ir_permissive_chan(wiphy, iftype,
850                                                    chandef->chan);
851
852         return _cfg80211_reg_can_beacon(wiphy, chandef, iftype, check_no_ir);
853 }
854 EXPORT_SYMBOL(cfg80211_reg_can_beacon_relax);
855
856 int cfg80211_set_monitor_channel(struct cfg80211_registered_device *rdev,
857                                  struct cfg80211_chan_def *chandef)
858 {
859         if (!rdev->ops->set_monitor_channel)
860                 return -EOPNOTSUPP;
861         if (!cfg80211_has_monitors_only(rdev))
862                 return -EBUSY;
863
864         return rdev_set_monitor_channel(rdev, chandef);
865 }
866
867 void
868 cfg80211_get_chan_state(struct wireless_dev *wdev,
869                         struct ieee80211_channel **chan,
870                         enum cfg80211_chan_mode *chanmode,
871                         u8 *radar_detect)
872 {
873         int ret;
874
875         *chan = NULL;
876         *chanmode = CHAN_MODE_UNDEFINED;
877
878         ASSERT_WDEV_LOCK(wdev);
879
880         if (wdev->netdev && !netif_running(wdev->netdev))
881                 return;
882
883         switch (wdev->iftype) {
884         case NL80211_IFTYPE_ADHOC:
885                 if (wdev->current_bss) {
886                         *chan = wdev->current_bss->pub.channel;
887                         *chanmode = (wdev->ibss_fixed &&
888                                      !wdev->ibss_dfs_possible)
889                                   ? CHAN_MODE_SHARED
890                                   : CHAN_MODE_EXCLUSIVE;
891
892                         /* consider worst-case - IBSS can try to return to the
893                          * original user-specified channel as creator */
894                         if (wdev->ibss_dfs_possible)
895                                 *radar_detect |= BIT(wdev->chandef.width);
896                         return;
897                 }
898                 break;
899         case NL80211_IFTYPE_STATION:
900         case NL80211_IFTYPE_P2P_CLIENT:
901                 if (wdev->current_bss) {
902                         *chan = wdev->current_bss->pub.channel;
903                         *chanmode = CHAN_MODE_SHARED;
904                         return;
905                 }
906                 break;
907         case NL80211_IFTYPE_AP:
908         case NL80211_IFTYPE_P2P_GO:
909                 if (wdev->cac_started) {
910                         *chan = wdev->chandef.chan;
911                         *chanmode = CHAN_MODE_SHARED;
912                         *radar_detect |= BIT(wdev->chandef.width);
913                 } else if (wdev->beacon_interval) {
914                         *chan = wdev->chandef.chan;
915                         *chanmode = CHAN_MODE_SHARED;
916
917                         ret = cfg80211_chandef_dfs_required(wdev->wiphy,
918                                                             &wdev->chandef,
919                                                             wdev->iftype);
920                         WARN_ON(ret < 0);
921                         if (ret > 0)
922                                 *radar_detect |= BIT(wdev->chandef.width);
923                 }
924                 return;
925         case NL80211_IFTYPE_MESH_POINT:
926                 if (wdev->mesh_id_len) {
927                         *chan = wdev->chandef.chan;
928                         *chanmode = CHAN_MODE_SHARED;
929
930                         ret = cfg80211_chandef_dfs_required(wdev->wiphy,
931                                                             &wdev->chandef,
932                                                             wdev->iftype);
933                         WARN_ON(ret < 0);
934                         if (ret > 0)
935                                 *radar_detect |= BIT(wdev->chandef.width);
936                 }
937                 return;
938         case NL80211_IFTYPE_OCB:
939                 if (wdev->chandef.chan) {
940                         *chan = wdev->chandef.chan;
941                         *chanmode = CHAN_MODE_SHARED;
942                         return;
943                 }
944                 break;
945         case NL80211_IFTYPE_MONITOR:
946         case NL80211_IFTYPE_AP_VLAN:
947         case NL80211_IFTYPE_WDS:
948         case NL80211_IFTYPE_P2P_DEVICE:
949                 /* these interface types don't really have a channel */
950                 return;
951         case NL80211_IFTYPE_UNSPECIFIED:
952         case NUM_NL80211_IFTYPES:
953                 WARN_ON(1);
954         }
955 }