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Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux
[uclinux-h8/linux.git] / net / wireless / reg.c
1 /*
2  * Copyright 2002-2005, Instant802 Networks, Inc.
3  * Copyright 2005-2006, Devicescape Software, Inc.
4  * Copyright 2007       Johannes Berg <johannes@sipsolutions.net>
5  * Copyright 2008       Luis R. Rodriguez <lrodriguz@atheros.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11
12 /**
13  * DOC: Wireless regulatory infrastructure
14  *
15  * The usual implementation is for a driver to read a device EEPROM to
16  * determine which regulatory domain it should be operating under, then
17  * looking up the allowable channels in a driver-local table and finally
18  * registering those channels in the wiphy structure.
19  *
20  * Another set of compliance enforcement is for drivers to use their
21  * own compliance limits which can be stored on the EEPROM. The host
22  * driver or firmware may ensure these are used.
23  *
24  * In addition to all this we provide an extra layer of regulatory
25  * conformance. For drivers which do not have any regulatory
26  * information CRDA provides the complete regulatory solution.
27  * For others it provides a community effort on further restrictions
28  * to enhance compliance.
29  *
30  * Note: When number of rules --> infinity we will not be able to
31  * index on alpha2 any more, instead we'll probably have to
32  * rely on some SHA1 checksum of the regdomain for example.
33  *
34  */
35
36 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
37
38 #include <linux/kernel.h>
39 #include <linux/export.h>
40 #include <linux/slab.h>
41 #include <linux/list.h>
42 #include <linux/random.h>
43 #include <linux/ctype.h>
44 #include <linux/nl80211.h>
45 #include <linux/platform_device.h>
46 #include <linux/moduleparam.h>
47 #include <net/cfg80211.h>
48 #include "core.h"
49 #include "reg.h"
50 #include "regdb.h"
51 #include "nl80211.h"
52
53 #ifdef CONFIG_CFG80211_REG_DEBUG
54 #define REG_DBG_PRINT(format, args...)                  \
55         printk(KERN_DEBUG pr_fmt(format), ##args)
56 #else
57 #define REG_DBG_PRINT(args...)
58 #endif
59
60 /* Receipt of information from last regulatory request */
61 static struct regulatory_request *last_request;
62
63 /* To trigger userspace events */
64 static struct platform_device *reg_pdev;
65
66 static struct device_type reg_device_type = {
67         .uevent = reg_device_uevent,
68 };
69
70 /*
71  * Central wireless core regulatory domains, we only need two,
72  * the current one and a world regulatory domain in case we have no
73  * information to give us an alpha2
74  */
75 const struct ieee80211_regdomain *cfg80211_regdomain;
76
77 /*
78  * Protects static reg.c components:
79  *     - cfg80211_world_regdom
80  *     - cfg80211_regdom
81  *     - last_request
82  */
83 static DEFINE_MUTEX(reg_mutex);
84
85 static inline void assert_reg_lock(void)
86 {
87         lockdep_assert_held(&reg_mutex);
88 }
89
90 /* Used to queue up regulatory hints */
91 static LIST_HEAD(reg_requests_list);
92 static spinlock_t reg_requests_lock;
93
94 /* Used to queue up beacon hints for review */
95 static LIST_HEAD(reg_pending_beacons);
96 static spinlock_t reg_pending_beacons_lock;
97
98 /* Used to keep track of processed beacon hints */
99 static LIST_HEAD(reg_beacon_list);
100
101 struct reg_beacon {
102         struct list_head list;
103         struct ieee80211_channel chan;
104 };
105
106 static void reg_todo(struct work_struct *work);
107 static DECLARE_WORK(reg_work, reg_todo);
108
109 static void reg_timeout_work(struct work_struct *work);
110 static DECLARE_DELAYED_WORK(reg_timeout, reg_timeout_work);
111
112 /* We keep a static world regulatory domain in case of the absence of CRDA */
113 static const struct ieee80211_regdomain world_regdom = {
114         .n_reg_rules = 5,
115         .alpha2 =  "00",
116         .reg_rules = {
117                 /* IEEE 802.11b/g, channels 1..11 */
118                 REG_RULE(2412-10, 2462+10, 40, 6, 20, 0),
119                 /* IEEE 802.11b/g, channels 12..13. No HT40
120                  * channel fits here. */
121                 REG_RULE(2467-10, 2472+10, 20, 6, 20,
122                         NL80211_RRF_PASSIVE_SCAN |
123                         NL80211_RRF_NO_IBSS),
124                 /* IEEE 802.11 channel 14 - Only JP enables
125                  * this and for 802.11b only */
126                 REG_RULE(2484-10, 2484+10, 20, 6, 20,
127                         NL80211_RRF_PASSIVE_SCAN |
128                         NL80211_RRF_NO_IBSS |
129                         NL80211_RRF_NO_OFDM),
130                 /* IEEE 802.11a, channel 36..48 */
131                 REG_RULE(5180-10, 5240+10, 40, 6, 20,
132                         NL80211_RRF_PASSIVE_SCAN |
133                         NL80211_RRF_NO_IBSS),
134
135                 /* NB: 5260 MHz - 5700 MHz requies DFS */
136
137                 /* IEEE 802.11a, channel 149..165 */
138                 REG_RULE(5745-10, 5825+10, 40, 6, 20,
139                         NL80211_RRF_PASSIVE_SCAN |
140                         NL80211_RRF_NO_IBSS),
141         }
142 };
143
144 static const struct ieee80211_regdomain *cfg80211_world_regdom =
145         &world_regdom;
146
147 static char *ieee80211_regdom = "00";
148 static char user_alpha2[2];
149
150 module_param(ieee80211_regdom, charp, 0444);
151 MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain code");
152
153 static void reset_regdomains(void)
154 {
155         /* avoid freeing static information or freeing something twice */
156         if (cfg80211_regdomain == cfg80211_world_regdom)
157                 cfg80211_regdomain = NULL;
158         if (cfg80211_world_regdom == &world_regdom)
159                 cfg80211_world_regdom = NULL;
160         if (cfg80211_regdomain == &world_regdom)
161                 cfg80211_regdomain = NULL;
162
163         kfree(cfg80211_regdomain);
164         kfree(cfg80211_world_regdom);
165
166         cfg80211_world_regdom = &world_regdom;
167         cfg80211_regdomain = NULL;
168 }
169
170 /*
171  * Dynamic world regulatory domain requested by the wireless
172  * core upon initialization
173  */
174 static void update_world_regdomain(const struct ieee80211_regdomain *rd)
175 {
176         BUG_ON(!last_request);
177
178         reset_regdomains();
179
180         cfg80211_world_regdom = rd;
181         cfg80211_regdomain = rd;
182 }
183
184 bool is_world_regdom(const char *alpha2)
185 {
186         if (!alpha2)
187                 return false;
188         if (alpha2[0] == '0' && alpha2[1] == '0')
189                 return true;
190         return false;
191 }
192
193 static bool is_alpha2_set(const char *alpha2)
194 {
195         if (!alpha2)
196                 return false;
197         if (alpha2[0] != 0 && alpha2[1] != 0)
198                 return true;
199         return false;
200 }
201
202 static bool is_unknown_alpha2(const char *alpha2)
203 {
204         if (!alpha2)
205                 return false;
206         /*
207          * Special case where regulatory domain was built by driver
208          * but a specific alpha2 cannot be determined
209          */
210         if (alpha2[0] == '9' && alpha2[1] == '9')
211                 return true;
212         return false;
213 }
214
215 static bool is_intersected_alpha2(const char *alpha2)
216 {
217         if (!alpha2)
218                 return false;
219         /*
220          * Special case where regulatory domain is the
221          * result of an intersection between two regulatory domain
222          * structures
223          */
224         if (alpha2[0] == '9' && alpha2[1] == '8')
225                 return true;
226         return false;
227 }
228
229 static bool is_an_alpha2(const char *alpha2)
230 {
231         if (!alpha2)
232                 return false;
233         if (isalpha(alpha2[0]) && isalpha(alpha2[1]))
234                 return true;
235         return false;
236 }
237
238 static bool alpha2_equal(const char *alpha2_x, const char *alpha2_y)
239 {
240         if (!alpha2_x || !alpha2_y)
241                 return false;
242         if (alpha2_x[0] == alpha2_y[0] &&
243                 alpha2_x[1] == alpha2_y[1])
244                 return true;
245         return false;
246 }
247
248 static bool regdom_changes(const char *alpha2)
249 {
250         assert_cfg80211_lock();
251
252         if (!cfg80211_regdomain)
253                 return true;
254         if (alpha2_equal(cfg80211_regdomain->alpha2, alpha2))
255                 return false;
256         return true;
257 }
258
259 /*
260  * The NL80211_REGDOM_SET_BY_USER regdom alpha2 is cached, this lets
261  * you know if a valid regulatory hint with NL80211_REGDOM_SET_BY_USER
262  * has ever been issued.
263  */
264 static bool is_user_regdom_saved(void)
265 {
266         if (user_alpha2[0] == '9' && user_alpha2[1] == '7')
267                 return false;
268
269         /* This would indicate a mistake on the design */
270         if (WARN((!is_world_regdom(user_alpha2) &&
271                   !is_an_alpha2(user_alpha2)),
272                  "Unexpected user alpha2: %c%c\n",
273                  user_alpha2[0],
274                  user_alpha2[1]))
275                 return false;
276
277         return true;
278 }
279
280 static int reg_copy_regd(const struct ieee80211_regdomain **dst_regd,
281                          const struct ieee80211_regdomain *src_regd)
282 {
283         struct ieee80211_regdomain *regd;
284         int size_of_regd = 0;
285         unsigned int i;
286
287         size_of_regd = sizeof(struct ieee80211_regdomain) +
288           ((src_regd->n_reg_rules + 1) * sizeof(struct ieee80211_reg_rule));
289
290         regd = kzalloc(size_of_regd, GFP_KERNEL);
291         if (!regd)
292                 return -ENOMEM;
293
294         memcpy(regd, src_regd, sizeof(struct ieee80211_regdomain));
295
296         for (i = 0; i < src_regd->n_reg_rules; i++)
297                 memcpy(&regd->reg_rules[i], &src_regd->reg_rules[i],
298                         sizeof(struct ieee80211_reg_rule));
299
300         *dst_regd = regd;
301         return 0;
302 }
303
304 #ifdef CONFIG_CFG80211_INTERNAL_REGDB
305 struct reg_regdb_search_request {
306         char alpha2[2];
307         struct list_head list;
308 };
309
310 static LIST_HEAD(reg_regdb_search_list);
311 static DEFINE_MUTEX(reg_regdb_search_mutex);
312
313 static void reg_regdb_search(struct work_struct *work)
314 {
315         struct reg_regdb_search_request *request;
316         const struct ieee80211_regdomain *curdom, *regdom;
317         int i, r;
318
319         mutex_lock(&reg_regdb_search_mutex);
320         while (!list_empty(&reg_regdb_search_list)) {
321                 request = list_first_entry(&reg_regdb_search_list,
322                                            struct reg_regdb_search_request,
323                                            list);
324                 list_del(&request->list);
325
326                 for (i=0; i<reg_regdb_size; i++) {
327                         curdom = reg_regdb[i];
328
329                         if (!memcmp(request->alpha2, curdom->alpha2, 2)) {
330                                 r = reg_copy_regd(&regdom, curdom);
331                                 if (r)
332                                         break;
333                                 mutex_lock(&cfg80211_mutex);
334                                 set_regdom(regdom);
335                                 mutex_unlock(&cfg80211_mutex);
336                                 break;
337                         }
338                 }
339
340                 kfree(request);
341         }
342         mutex_unlock(&reg_regdb_search_mutex);
343 }
344
345 static DECLARE_WORK(reg_regdb_work, reg_regdb_search);
346
347 static void reg_regdb_query(const char *alpha2)
348 {
349         struct reg_regdb_search_request *request;
350
351         if (!alpha2)
352                 return;
353
354         request = kzalloc(sizeof(struct reg_regdb_search_request), GFP_KERNEL);
355         if (!request)
356                 return;
357
358         memcpy(request->alpha2, alpha2, 2);
359
360         mutex_lock(&reg_regdb_search_mutex);
361         list_add_tail(&request->list, &reg_regdb_search_list);
362         mutex_unlock(&reg_regdb_search_mutex);
363
364         schedule_work(&reg_regdb_work);
365 }
366 #else
367 static inline void reg_regdb_query(const char *alpha2) {}
368 #endif /* CONFIG_CFG80211_INTERNAL_REGDB */
369
370 /*
371  * This lets us keep regulatory code which is updated on a regulatory
372  * basis in userspace. Country information is filled in by
373  * reg_device_uevent
374  */
375 static int call_crda(const char *alpha2)
376 {
377         if (!is_world_regdom((char *) alpha2))
378                 pr_info("Calling CRDA for country: %c%c\n",
379                         alpha2[0], alpha2[1]);
380         else
381                 pr_info("Calling CRDA to update world regulatory domain\n");
382
383         /* query internal regulatory database (if it exists) */
384         reg_regdb_query(alpha2);
385
386         return kobject_uevent(&reg_pdev->dev.kobj, KOBJ_CHANGE);
387 }
388
389 /* Used by nl80211 before kmalloc'ing our regulatory domain */
390 bool reg_is_valid_request(const char *alpha2)
391 {
392         assert_cfg80211_lock();
393
394         if (!last_request)
395                 return false;
396
397         return alpha2_equal(last_request->alpha2, alpha2);
398 }
399
400 /* Sanity check on a regulatory rule */
401 static bool is_valid_reg_rule(const struct ieee80211_reg_rule *rule)
402 {
403         const struct ieee80211_freq_range *freq_range = &rule->freq_range;
404         u32 freq_diff;
405
406         if (freq_range->start_freq_khz <= 0 || freq_range->end_freq_khz <= 0)
407                 return false;
408
409         if (freq_range->start_freq_khz > freq_range->end_freq_khz)
410                 return false;
411
412         freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
413
414         if (freq_range->end_freq_khz <= freq_range->start_freq_khz ||
415                         freq_range->max_bandwidth_khz > freq_diff)
416                 return false;
417
418         return true;
419 }
420
421 static bool is_valid_rd(const struct ieee80211_regdomain *rd)
422 {
423         const struct ieee80211_reg_rule *reg_rule = NULL;
424         unsigned int i;
425
426         if (!rd->n_reg_rules)
427                 return false;
428
429         if (WARN_ON(rd->n_reg_rules > NL80211_MAX_SUPP_REG_RULES))
430                 return false;
431
432         for (i = 0; i < rd->n_reg_rules; i++) {
433                 reg_rule = &rd->reg_rules[i];
434                 if (!is_valid_reg_rule(reg_rule))
435                         return false;
436         }
437
438         return true;
439 }
440
441 static bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_range,
442                             u32 center_freq_khz,
443                             u32 bw_khz)
444 {
445         u32 start_freq_khz, end_freq_khz;
446
447         start_freq_khz = center_freq_khz - (bw_khz/2);
448         end_freq_khz = center_freq_khz + (bw_khz/2);
449
450         if (start_freq_khz >= freq_range->start_freq_khz &&
451             end_freq_khz <= freq_range->end_freq_khz)
452                 return true;
453
454         return false;
455 }
456
457 /**
458  * freq_in_rule_band - tells us if a frequency is in a frequency band
459  * @freq_range: frequency rule we want to query
460  * @freq_khz: frequency we are inquiring about
461  *
462  * This lets us know if a specific frequency rule is or is not relevant to
463  * a specific frequency's band. Bands are device specific and artificial
464  * definitions (the "2.4 GHz band" and the "5 GHz band"), however it is
465  * safe for now to assume that a frequency rule should not be part of a
466  * frequency's band if the start freq or end freq are off by more than 2 GHz.
467  * This resolution can be lowered and should be considered as we add
468  * regulatory rule support for other "bands".
469  **/
470 static bool freq_in_rule_band(const struct ieee80211_freq_range *freq_range,
471         u32 freq_khz)
472 {
473 #define ONE_GHZ_IN_KHZ  1000000
474         if (abs(freq_khz - freq_range->start_freq_khz) <= (2 * ONE_GHZ_IN_KHZ))
475                 return true;
476         if (abs(freq_khz - freq_range->end_freq_khz) <= (2 * ONE_GHZ_IN_KHZ))
477                 return true;
478         return false;
479 #undef ONE_GHZ_IN_KHZ
480 }
481
482 /*
483  * Helper for regdom_intersect(), this does the real
484  * mathematical intersection fun
485  */
486 static int reg_rules_intersect(
487         const struct ieee80211_reg_rule *rule1,
488         const struct ieee80211_reg_rule *rule2,
489         struct ieee80211_reg_rule *intersected_rule)
490 {
491         const struct ieee80211_freq_range *freq_range1, *freq_range2;
492         struct ieee80211_freq_range *freq_range;
493         const struct ieee80211_power_rule *power_rule1, *power_rule2;
494         struct ieee80211_power_rule *power_rule;
495         u32 freq_diff;
496
497         freq_range1 = &rule1->freq_range;
498         freq_range2 = &rule2->freq_range;
499         freq_range = &intersected_rule->freq_range;
500
501         power_rule1 = &rule1->power_rule;
502         power_rule2 = &rule2->power_rule;
503         power_rule = &intersected_rule->power_rule;
504
505         freq_range->start_freq_khz = max(freq_range1->start_freq_khz,
506                 freq_range2->start_freq_khz);
507         freq_range->end_freq_khz = min(freq_range1->end_freq_khz,
508                 freq_range2->end_freq_khz);
509         freq_range->max_bandwidth_khz = min(freq_range1->max_bandwidth_khz,
510                 freq_range2->max_bandwidth_khz);
511
512         freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
513         if (freq_range->max_bandwidth_khz > freq_diff)
514                 freq_range->max_bandwidth_khz = freq_diff;
515
516         power_rule->max_eirp = min(power_rule1->max_eirp,
517                 power_rule2->max_eirp);
518         power_rule->max_antenna_gain = min(power_rule1->max_antenna_gain,
519                 power_rule2->max_antenna_gain);
520
521         intersected_rule->flags = (rule1->flags | rule2->flags);
522
523         if (!is_valid_reg_rule(intersected_rule))
524                 return -EINVAL;
525
526         return 0;
527 }
528
529 /**
530  * regdom_intersect - do the intersection between two regulatory domains
531  * @rd1: first regulatory domain
532  * @rd2: second regulatory domain
533  *
534  * Use this function to get the intersection between two regulatory domains.
535  * Once completed we will mark the alpha2 for the rd as intersected, "98",
536  * as no one single alpha2 can represent this regulatory domain.
537  *
538  * Returns a pointer to the regulatory domain structure which will hold the
539  * resulting intersection of rules between rd1 and rd2. We will
540  * kzalloc() this structure for you.
541  */
542 static struct ieee80211_regdomain *regdom_intersect(
543         const struct ieee80211_regdomain *rd1,
544         const struct ieee80211_regdomain *rd2)
545 {
546         int r, size_of_regd;
547         unsigned int x, y;
548         unsigned int num_rules = 0, rule_idx = 0;
549         const struct ieee80211_reg_rule *rule1, *rule2;
550         struct ieee80211_reg_rule *intersected_rule;
551         struct ieee80211_regdomain *rd;
552         /* This is just a dummy holder to help us count */
553         struct ieee80211_reg_rule irule;
554
555         /* Uses the stack temporarily for counter arithmetic */
556         intersected_rule = &irule;
557
558         memset(intersected_rule, 0, sizeof(struct ieee80211_reg_rule));
559
560         if (!rd1 || !rd2)
561                 return NULL;
562
563         /*
564          * First we get a count of the rules we'll need, then we actually
565          * build them. This is to so we can malloc() and free() a
566          * regdomain once. The reason we use reg_rules_intersect() here
567          * is it will return -EINVAL if the rule computed makes no sense.
568          * All rules that do check out OK are valid.
569          */
570
571         for (x = 0; x < rd1->n_reg_rules; x++) {
572                 rule1 = &rd1->reg_rules[x];
573                 for (y = 0; y < rd2->n_reg_rules; y++) {
574                         rule2 = &rd2->reg_rules[y];
575                         if (!reg_rules_intersect(rule1, rule2,
576                                         intersected_rule))
577                                 num_rules++;
578                         memset(intersected_rule, 0,
579                                         sizeof(struct ieee80211_reg_rule));
580                 }
581         }
582
583         if (!num_rules)
584                 return NULL;
585
586         size_of_regd = sizeof(struct ieee80211_regdomain) +
587                 ((num_rules + 1) * sizeof(struct ieee80211_reg_rule));
588
589         rd = kzalloc(size_of_regd, GFP_KERNEL);
590         if (!rd)
591                 return NULL;
592
593         for (x = 0; x < rd1->n_reg_rules; x++) {
594                 rule1 = &rd1->reg_rules[x];
595                 for (y = 0; y < rd2->n_reg_rules; y++) {
596                         rule2 = &rd2->reg_rules[y];
597                         /*
598                          * This time around instead of using the stack lets
599                          * write to the target rule directly saving ourselves
600                          * a memcpy()
601                          */
602                         intersected_rule = &rd->reg_rules[rule_idx];
603                         r = reg_rules_intersect(rule1, rule2,
604                                 intersected_rule);
605                         /*
606                          * No need to memset here the intersected rule here as
607                          * we're not using the stack anymore
608                          */
609                         if (r)
610                                 continue;
611                         rule_idx++;
612                 }
613         }
614
615         if (rule_idx != num_rules) {
616                 kfree(rd);
617                 return NULL;
618         }
619
620         rd->n_reg_rules = num_rules;
621         rd->alpha2[0] = '9';
622         rd->alpha2[1] = '8';
623
624         return rd;
625 }
626
627 /*
628  * XXX: add support for the rest of enum nl80211_reg_rule_flags, we may
629  * want to just have the channel structure use these
630  */
631 static u32 map_regdom_flags(u32 rd_flags)
632 {
633         u32 channel_flags = 0;
634         if (rd_flags & NL80211_RRF_PASSIVE_SCAN)
635                 channel_flags |= IEEE80211_CHAN_PASSIVE_SCAN;
636         if (rd_flags & NL80211_RRF_NO_IBSS)
637                 channel_flags |= IEEE80211_CHAN_NO_IBSS;
638         if (rd_flags & NL80211_RRF_DFS)
639                 channel_flags |= IEEE80211_CHAN_RADAR;
640         return channel_flags;
641 }
642
643 static int freq_reg_info_regd(struct wiphy *wiphy,
644                               u32 center_freq,
645                               u32 desired_bw_khz,
646                               const struct ieee80211_reg_rule **reg_rule,
647                               const struct ieee80211_regdomain *custom_regd)
648 {
649         int i;
650         bool band_rule_found = false;
651         const struct ieee80211_regdomain *regd;
652         bool bw_fits = false;
653
654         if (!desired_bw_khz)
655                 desired_bw_khz = MHZ_TO_KHZ(20);
656
657         regd = custom_regd ? custom_regd : cfg80211_regdomain;
658
659         /*
660          * Follow the driver's regulatory domain, if present, unless a country
661          * IE has been processed or a user wants to help complaince further
662          */
663         if (!custom_regd &&
664             last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
665             last_request->initiator != NL80211_REGDOM_SET_BY_USER &&
666             wiphy->regd)
667                 regd = wiphy->regd;
668
669         if (!regd)
670                 return -EINVAL;
671
672         for (i = 0; i < regd->n_reg_rules; i++) {
673                 const struct ieee80211_reg_rule *rr;
674                 const struct ieee80211_freq_range *fr = NULL;
675
676                 rr = &regd->reg_rules[i];
677                 fr = &rr->freq_range;
678
679                 /*
680                  * We only need to know if one frequency rule was
681                  * was in center_freq's band, that's enough, so lets
682                  * not overwrite it once found
683                  */
684                 if (!band_rule_found)
685                         band_rule_found = freq_in_rule_band(fr, center_freq);
686
687                 bw_fits = reg_does_bw_fit(fr,
688                                           center_freq,
689                                           desired_bw_khz);
690
691                 if (band_rule_found && bw_fits) {
692                         *reg_rule = rr;
693                         return 0;
694                 }
695         }
696
697         if (!band_rule_found)
698                 return -ERANGE;
699
700         return -EINVAL;
701 }
702
703 int freq_reg_info(struct wiphy *wiphy,
704                   u32 center_freq,
705                   u32 desired_bw_khz,
706                   const struct ieee80211_reg_rule **reg_rule)
707 {
708         assert_cfg80211_lock();
709         return freq_reg_info_regd(wiphy,
710                                   center_freq,
711                                   desired_bw_khz,
712                                   reg_rule,
713                                   NULL);
714 }
715 EXPORT_SYMBOL(freq_reg_info);
716
717 #ifdef CONFIG_CFG80211_REG_DEBUG
718 static const char *reg_initiator_name(enum nl80211_reg_initiator initiator)
719 {
720         switch (initiator) {
721         case NL80211_REGDOM_SET_BY_CORE:
722                 return "Set by core";
723         case NL80211_REGDOM_SET_BY_USER:
724                 return "Set by user";
725         case NL80211_REGDOM_SET_BY_DRIVER:
726                 return "Set by driver";
727         case NL80211_REGDOM_SET_BY_COUNTRY_IE:
728                 return "Set by country IE";
729         default:
730                 WARN_ON(1);
731                 return "Set by bug";
732         }
733 }
734
735 static void chan_reg_rule_print_dbg(struct ieee80211_channel *chan,
736                                     u32 desired_bw_khz,
737                                     const struct ieee80211_reg_rule *reg_rule)
738 {
739         const struct ieee80211_power_rule *power_rule;
740         const struct ieee80211_freq_range *freq_range;
741         char max_antenna_gain[32];
742
743         power_rule = &reg_rule->power_rule;
744         freq_range = &reg_rule->freq_range;
745
746         if (!power_rule->max_antenna_gain)
747                 snprintf(max_antenna_gain, 32, "N/A");
748         else
749                 snprintf(max_antenna_gain, 32, "%d", power_rule->max_antenna_gain);
750
751         REG_DBG_PRINT("Updating information on frequency %d MHz "
752                       "for a %d MHz width channel with regulatory rule:\n",
753                       chan->center_freq,
754                       KHZ_TO_MHZ(desired_bw_khz));
755
756         REG_DBG_PRINT("%d KHz - %d KHz @ %d KHz), (%s mBi, %d mBm)\n",
757                       freq_range->start_freq_khz,
758                       freq_range->end_freq_khz,
759                       freq_range->max_bandwidth_khz,
760                       max_antenna_gain,
761                       power_rule->max_eirp);
762 }
763 #else
764 static void chan_reg_rule_print_dbg(struct ieee80211_channel *chan,
765                                     u32 desired_bw_khz,
766                                     const struct ieee80211_reg_rule *reg_rule)
767 {
768         return;
769 }
770 #endif
771
772 /*
773  * Note that right now we assume the desired channel bandwidth
774  * is always 20 MHz for each individual channel (HT40 uses 20 MHz
775  * per channel, the primary and the extension channel). To support
776  * smaller custom bandwidths such as 5 MHz or 10 MHz we'll need a
777  * new ieee80211_channel.target_bw and re run the regulatory check
778  * on the wiphy with the target_bw specified. Then we can simply use
779  * that below for the desired_bw_khz below.
780  */
781 static void handle_channel(struct wiphy *wiphy,
782                            enum nl80211_reg_initiator initiator,
783                            enum ieee80211_band band,
784                            unsigned int chan_idx)
785 {
786         int r;
787         u32 flags, bw_flags = 0;
788         u32 desired_bw_khz = MHZ_TO_KHZ(20);
789         const struct ieee80211_reg_rule *reg_rule = NULL;
790         const struct ieee80211_power_rule *power_rule = NULL;
791         const struct ieee80211_freq_range *freq_range = NULL;
792         struct ieee80211_supported_band *sband;
793         struct ieee80211_channel *chan;
794         struct wiphy *request_wiphy = NULL;
795
796         assert_cfg80211_lock();
797
798         request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
799
800         sband = wiphy->bands[band];
801         BUG_ON(chan_idx >= sband->n_channels);
802         chan = &sband->channels[chan_idx];
803
804         flags = chan->orig_flags;
805
806         r = freq_reg_info(wiphy,
807                           MHZ_TO_KHZ(chan->center_freq),
808                           desired_bw_khz,
809                           &reg_rule);
810
811         if (r) {
812                 /*
813                  * We will disable all channels that do not match our
814                  * received regulatory rule unless the hint is coming
815                  * from a Country IE and the Country IE had no information
816                  * about a band. The IEEE 802.11 spec allows for an AP
817                  * to send only a subset of the regulatory rules allowed,
818                  * so an AP in the US that only supports 2.4 GHz may only send
819                  * a country IE with information for the 2.4 GHz band
820                  * while 5 GHz is still supported.
821                  */
822                 if (initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE &&
823                     r == -ERANGE)
824                         return;
825
826                 REG_DBG_PRINT("Disabling freq %d MHz\n", chan->center_freq);
827                 chan->flags = IEEE80211_CHAN_DISABLED;
828                 return;
829         }
830
831         chan_reg_rule_print_dbg(chan, desired_bw_khz, reg_rule);
832
833         power_rule = &reg_rule->power_rule;
834         freq_range = &reg_rule->freq_range;
835
836         if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
837                 bw_flags = IEEE80211_CHAN_NO_HT40;
838
839         if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
840             request_wiphy && request_wiphy == wiphy &&
841             request_wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY) {
842                 /*
843                  * This guarantees the driver's requested regulatory domain
844                  * will always be used as a base for further regulatory
845                  * settings
846                  */
847                 chan->flags = chan->orig_flags =
848                         map_regdom_flags(reg_rule->flags) | bw_flags;
849                 chan->max_antenna_gain = chan->orig_mag =
850                         (int) MBI_TO_DBI(power_rule->max_antenna_gain);
851                 chan->max_power = chan->orig_mpwr =
852                         (int) MBM_TO_DBM(power_rule->max_eirp);
853                 return;
854         }
855
856         chan->beacon_found = false;
857         chan->flags = flags | bw_flags | map_regdom_flags(reg_rule->flags);
858         chan->max_antenna_gain = min(chan->orig_mag,
859                 (int) MBI_TO_DBI(power_rule->max_antenna_gain));
860         if (chan->orig_mpwr)
861                 chan->max_power = min(chan->orig_mpwr,
862                         (int) MBM_TO_DBM(power_rule->max_eirp));
863         else
864                 chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
865 }
866
867 static void handle_band(struct wiphy *wiphy,
868                         enum ieee80211_band band,
869                         enum nl80211_reg_initiator initiator)
870 {
871         unsigned int i;
872         struct ieee80211_supported_band *sband;
873
874         BUG_ON(!wiphy->bands[band]);
875         sband = wiphy->bands[band];
876
877         for (i = 0; i < sband->n_channels; i++)
878                 handle_channel(wiphy, initiator, band, i);
879 }
880
881 static bool ignore_reg_update(struct wiphy *wiphy,
882                               enum nl80211_reg_initiator initiator)
883 {
884         if (!last_request) {
885                 REG_DBG_PRINT("Ignoring regulatory request %s since "
886                               "last_request is not set\n",
887                               reg_initiator_name(initiator));
888                 return true;
889         }
890
891         if (initiator == NL80211_REGDOM_SET_BY_CORE &&
892             wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY) {
893                 REG_DBG_PRINT("Ignoring regulatory request %s "
894                               "since the driver uses its own custom "
895                               "regulatory domain\n",
896                               reg_initiator_name(initiator));
897                 return true;
898         }
899
900         /*
901          * wiphy->regd will be set once the device has its own
902          * desired regulatory domain set
903          */
904         if (wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY && !wiphy->regd &&
905             initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
906             !is_world_regdom(last_request->alpha2)) {
907                 REG_DBG_PRINT("Ignoring regulatory request %s "
908                               "since the driver requires its own regulatory "
909                               "domain to be set first\n",
910                               reg_initiator_name(initiator));
911                 return true;
912         }
913
914         return false;
915 }
916
917 static void handle_reg_beacon(struct wiphy *wiphy,
918                               unsigned int chan_idx,
919                               struct reg_beacon *reg_beacon)
920 {
921         struct ieee80211_supported_band *sband;
922         struct ieee80211_channel *chan;
923         bool channel_changed = false;
924         struct ieee80211_channel chan_before;
925
926         assert_cfg80211_lock();
927
928         sband = wiphy->bands[reg_beacon->chan.band];
929         chan = &sband->channels[chan_idx];
930
931         if (likely(chan->center_freq != reg_beacon->chan.center_freq))
932                 return;
933
934         if (chan->beacon_found)
935                 return;
936
937         chan->beacon_found = true;
938
939         if (wiphy->flags & WIPHY_FLAG_DISABLE_BEACON_HINTS)
940                 return;
941
942         chan_before.center_freq = chan->center_freq;
943         chan_before.flags = chan->flags;
944
945         if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN) {
946                 chan->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
947                 channel_changed = true;
948         }
949
950         if (chan->flags & IEEE80211_CHAN_NO_IBSS) {
951                 chan->flags &= ~IEEE80211_CHAN_NO_IBSS;
952                 channel_changed = true;
953         }
954
955         if (channel_changed)
956                 nl80211_send_beacon_hint_event(wiphy, &chan_before, chan);
957 }
958
959 /*
960  * Called when a scan on a wiphy finds a beacon on
961  * new channel
962  */
963 static void wiphy_update_new_beacon(struct wiphy *wiphy,
964                                     struct reg_beacon *reg_beacon)
965 {
966         unsigned int i;
967         struct ieee80211_supported_band *sband;
968
969         assert_cfg80211_lock();
970
971         if (!wiphy->bands[reg_beacon->chan.band])
972                 return;
973
974         sband = wiphy->bands[reg_beacon->chan.band];
975
976         for (i = 0; i < sband->n_channels; i++)
977                 handle_reg_beacon(wiphy, i, reg_beacon);
978 }
979
980 /*
981  * Called upon reg changes or a new wiphy is added
982  */
983 static void wiphy_update_beacon_reg(struct wiphy *wiphy)
984 {
985         unsigned int i;
986         struct ieee80211_supported_band *sband;
987         struct reg_beacon *reg_beacon;
988
989         assert_cfg80211_lock();
990
991         if (list_empty(&reg_beacon_list))
992                 return;
993
994         list_for_each_entry(reg_beacon, &reg_beacon_list, list) {
995                 if (!wiphy->bands[reg_beacon->chan.band])
996                         continue;
997                 sband = wiphy->bands[reg_beacon->chan.band];
998                 for (i = 0; i < sband->n_channels; i++)
999                         handle_reg_beacon(wiphy, i, reg_beacon);
1000         }
1001 }
1002
1003 static bool reg_is_world_roaming(struct wiphy *wiphy)
1004 {
1005         if (is_world_regdom(cfg80211_regdomain->alpha2) ||
1006             (wiphy->regd && is_world_regdom(wiphy->regd->alpha2)))
1007                 return true;
1008         if (last_request &&
1009             last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1010             wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY)
1011                 return true;
1012         return false;
1013 }
1014
1015 /* Reap the advantages of previously found beacons */
1016 static void reg_process_beacons(struct wiphy *wiphy)
1017 {
1018         /*
1019          * Means we are just firing up cfg80211, so no beacons would
1020          * have been processed yet.
1021          */
1022         if (!last_request)
1023                 return;
1024         if (!reg_is_world_roaming(wiphy))
1025                 return;
1026         wiphy_update_beacon_reg(wiphy);
1027 }
1028
1029 static bool is_ht40_not_allowed(struct ieee80211_channel *chan)
1030 {
1031         if (!chan)
1032                 return true;
1033         if (chan->flags & IEEE80211_CHAN_DISABLED)
1034                 return true;
1035         /* This would happen when regulatory rules disallow HT40 completely */
1036         if (IEEE80211_CHAN_NO_HT40 == (chan->flags & (IEEE80211_CHAN_NO_HT40)))
1037                 return true;
1038         return false;
1039 }
1040
1041 static void reg_process_ht_flags_channel(struct wiphy *wiphy,
1042                                          enum ieee80211_band band,
1043                                          unsigned int chan_idx)
1044 {
1045         struct ieee80211_supported_band *sband;
1046         struct ieee80211_channel *channel;
1047         struct ieee80211_channel *channel_before = NULL, *channel_after = NULL;
1048         unsigned int i;
1049
1050         assert_cfg80211_lock();
1051
1052         sband = wiphy->bands[band];
1053         BUG_ON(chan_idx >= sband->n_channels);
1054         channel = &sband->channels[chan_idx];
1055
1056         if (is_ht40_not_allowed(channel)) {
1057                 channel->flags |= IEEE80211_CHAN_NO_HT40;
1058                 return;
1059         }
1060
1061         /*
1062          * We need to ensure the extension channels exist to
1063          * be able to use HT40- or HT40+, this finds them (or not)
1064          */
1065         for (i = 0; i < sband->n_channels; i++) {
1066                 struct ieee80211_channel *c = &sband->channels[i];
1067                 if (c->center_freq == (channel->center_freq - 20))
1068                         channel_before = c;
1069                 if (c->center_freq == (channel->center_freq + 20))
1070                         channel_after = c;
1071         }
1072
1073         /*
1074          * Please note that this assumes target bandwidth is 20 MHz,
1075          * if that ever changes we also need to change the below logic
1076          * to include that as well.
1077          */
1078         if (is_ht40_not_allowed(channel_before))
1079                 channel->flags |= IEEE80211_CHAN_NO_HT40MINUS;
1080         else
1081                 channel->flags &= ~IEEE80211_CHAN_NO_HT40MINUS;
1082
1083         if (is_ht40_not_allowed(channel_after))
1084                 channel->flags |= IEEE80211_CHAN_NO_HT40PLUS;
1085         else
1086                 channel->flags &= ~IEEE80211_CHAN_NO_HT40PLUS;
1087 }
1088
1089 static void reg_process_ht_flags_band(struct wiphy *wiphy,
1090                                       enum ieee80211_band band)
1091 {
1092         unsigned int i;
1093         struct ieee80211_supported_band *sband;
1094
1095         BUG_ON(!wiphy->bands[band]);
1096         sband = wiphy->bands[band];
1097
1098         for (i = 0; i < sband->n_channels; i++)
1099                 reg_process_ht_flags_channel(wiphy, band, i);
1100 }
1101
1102 static void reg_process_ht_flags(struct wiphy *wiphy)
1103 {
1104         enum ieee80211_band band;
1105
1106         if (!wiphy)
1107                 return;
1108
1109         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1110                 if (wiphy->bands[band])
1111                         reg_process_ht_flags_band(wiphy, band);
1112         }
1113
1114 }
1115
1116 static void wiphy_update_regulatory(struct wiphy *wiphy,
1117                                     enum nl80211_reg_initiator initiator)
1118 {
1119         enum ieee80211_band band;
1120
1121         assert_reg_lock();
1122
1123         if (ignore_reg_update(wiphy, initiator))
1124                 return;
1125
1126         last_request->dfs_region = cfg80211_regdomain->dfs_region;
1127
1128         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1129                 if (wiphy->bands[band])
1130                         handle_band(wiphy, band, initiator);
1131         }
1132
1133         reg_process_beacons(wiphy);
1134         reg_process_ht_flags(wiphy);
1135         if (wiphy->reg_notifier)
1136                 wiphy->reg_notifier(wiphy, last_request);
1137 }
1138
1139 void regulatory_update(struct wiphy *wiphy,
1140                        enum nl80211_reg_initiator setby)
1141 {
1142         mutex_lock(&reg_mutex);
1143         wiphy_update_regulatory(wiphy, setby);
1144         mutex_unlock(&reg_mutex);
1145 }
1146
1147 static void update_all_wiphy_regulatory(enum nl80211_reg_initiator initiator)
1148 {
1149         struct cfg80211_registered_device *rdev;
1150
1151         list_for_each_entry(rdev, &cfg80211_rdev_list, list)
1152                 wiphy_update_regulatory(&rdev->wiphy, initiator);
1153 }
1154
1155 static void handle_channel_custom(struct wiphy *wiphy,
1156                                   enum ieee80211_band band,
1157                                   unsigned int chan_idx,
1158                                   const struct ieee80211_regdomain *regd)
1159 {
1160         int r;
1161         u32 desired_bw_khz = MHZ_TO_KHZ(20);
1162         u32 bw_flags = 0;
1163         const struct ieee80211_reg_rule *reg_rule = NULL;
1164         const struct ieee80211_power_rule *power_rule = NULL;
1165         const struct ieee80211_freq_range *freq_range = NULL;
1166         struct ieee80211_supported_band *sband;
1167         struct ieee80211_channel *chan;
1168
1169         assert_reg_lock();
1170
1171         sband = wiphy->bands[band];
1172         BUG_ON(chan_idx >= sband->n_channels);
1173         chan = &sband->channels[chan_idx];
1174
1175         r = freq_reg_info_regd(wiphy,
1176                                MHZ_TO_KHZ(chan->center_freq),
1177                                desired_bw_khz,
1178                                &reg_rule,
1179                                regd);
1180
1181         if (r) {
1182                 REG_DBG_PRINT("Disabling freq %d MHz as custom "
1183                               "regd has no rule that fits a %d MHz "
1184                               "wide channel\n",
1185                               chan->center_freq,
1186                               KHZ_TO_MHZ(desired_bw_khz));
1187                 chan->flags = IEEE80211_CHAN_DISABLED;
1188                 return;
1189         }
1190
1191         chan_reg_rule_print_dbg(chan, desired_bw_khz, reg_rule);
1192
1193         power_rule = &reg_rule->power_rule;
1194         freq_range = &reg_rule->freq_range;
1195
1196         if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
1197                 bw_flags = IEEE80211_CHAN_NO_HT40;
1198
1199         chan->flags |= map_regdom_flags(reg_rule->flags) | bw_flags;
1200         chan->max_antenna_gain = (int) MBI_TO_DBI(power_rule->max_antenna_gain);
1201         chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
1202 }
1203
1204 static void handle_band_custom(struct wiphy *wiphy, enum ieee80211_band band,
1205                                const struct ieee80211_regdomain *regd)
1206 {
1207         unsigned int i;
1208         struct ieee80211_supported_band *sband;
1209
1210         BUG_ON(!wiphy->bands[band]);
1211         sband = wiphy->bands[band];
1212
1213         for (i = 0; i < sband->n_channels; i++)
1214                 handle_channel_custom(wiphy, band, i, regd);
1215 }
1216
1217 /* Used by drivers prior to wiphy registration */
1218 void wiphy_apply_custom_regulatory(struct wiphy *wiphy,
1219                                    const struct ieee80211_regdomain *regd)
1220 {
1221         enum ieee80211_band band;
1222         unsigned int bands_set = 0;
1223
1224         mutex_lock(&reg_mutex);
1225         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1226                 if (!wiphy->bands[band])
1227                         continue;
1228                 handle_band_custom(wiphy, band, regd);
1229                 bands_set++;
1230         }
1231         mutex_unlock(&reg_mutex);
1232
1233         /*
1234          * no point in calling this if it won't have any effect
1235          * on your device's supportd bands.
1236          */
1237         WARN_ON(!bands_set);
1238 }
1239 EXPORT_SYMBOL(wiphy_apply_custom_regulatory);
1240
1241 /*
1242  * Return value which can be used by ignore_request() to indicate
1243  * it has been determined we should intersect two regulatory domains
1244  */
1245 #define REG_INTERSECT   1
1246
1247 /* This has the logic which determines when a new request
1248  * should be ignored. */
1249 static int ignore_request(struct wiphy *wiphy,
1250                           struct regulatory_request *pending_request)
1251 {
1252         struct wiphy *last_wiphy = NULL;
1253
1254         assert_cfg80211_lock();
1255
1256         /* All initial requests are respected */
1257         if (!last_request)
1258                 return 0;
1259
1260         switch (pending_request->initiator) {
1261         case NL80211_REGDOM_SET_BY_CORE:
1262                 return 0;
1263         case NL80211_REGDOM_SET_BY_COUNTRY_IE:
1264
1265                 last_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
1266
1267                 if (unlikely(!is_an_alpha2(pending_request->alpha2)))
1268                         return -EINVAL;
1269                 if (last_request->initiator ==
1270                     NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1271                         if (last_wiphy != wiphy) {
1272                                 /*
1273                                  * Two cards with two APs claiming different
1274                                  * Country IE alpha2s. We could
1275                                  * intersect them, but that seems unlikely
1276                                  * to be correct. Reject second one for now.
1277                                  */
1278                                 if (regdom_changes(pending_request->alpha2))
1279                                         return -EOPNOTSUPP;
1280                                 return -EALREADY;
1281                         }
1282                         /*
1283                          * Two consecutive Country IE hints on the same wiphy.
1284                          * This should be picked up early by the driver/stack
1285                          */
1286                         if (WARN_ON(regdom_changes(pending_request->alpha2)))
1287                                 return 0;
1288                         return -EALREADY;
1289                 }
1290                 return 0;
1291         case NL80211_REGDOM_SET_BY_DRIVER:
1292                 if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE) {
1293                         if (regdom_changes(pending_request->alpha2))
1294                                 return 0;
1295                         return -EALREADY;
1296                 }
1297
1298                 /*
1299                  * This would happen if you unplug and plug your card
1300                  * back in or if you add a new device for which the previously
1301                  * loaded card also agrees on the regulatory domain.
1302                  */
1303                 if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1304                     !regdom_changes(pending_request->alpha2))
1305                         return -EALREADY;
1306
1307                 return REG_INTERSECT;
1308         case NL80211_REGDOM_SET_BY_USER:
1309                 if (last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE)
1310                         return REG_INTERSECT;
1311                 /*
1312                  * If the user knows better the user should set the regdom
1313                  * to their country before the IE is picked up
1314                  */
1315                 if (last_request->initiator == NL80211_REGDOM_SET_BY_USER &&
1316                           last_request->intersect)
1317                         return -EOPNOTSUPP;
1318                 /*
1319                  * Process user requests only after previous user/driver/core
1320                  * requests have been processed
1321                  */
1322                 if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE ||
1323                     last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER ||
1324                     last_request->initiator == NL80211_REGDOM_SET_BY_USER) {
1325                         if (regdom_changes(last_request->alpha2))
1326                                 return -EAGAIN;
1327                 }
1328
1329                 if (!regdom_changes(pending_request->alpha2))
1330                         return -EALREADY;
1331
1332                 return 0;
1333         }
1334
1335         return -EINVAL;
1336 }
1337
1338 static void reg_set_request_processed(void)
1339 {
1340         bool need_more_processing = false;
1341
1342         last_request->processed = true;
1343
1344         spin_lock(&reg_requests_lock);
1345         if (!list_empty(&reg_requests_list))
1346                 need_more_processing = true;
1347         spin_unlock(&reg_requests_lock);
1348
1349         if (last_request->initiator == NL80211_REGDOM_SET_BY_USER)
1350                 cancel_delayed_work_sync(&reg_timeout);
1351
1352         if (need_more_processing)
1353                 schedule_work(&reg_work);
1354 }
1355
1356 /**
1357  * __regulatory_hint - hint to the wireless core a regulatory domain
1358  * @wiphy: if the hint comes from country information from an AP, this
1359  *      is required to be set to the wiphy that received the information
1360  * @pending_request: the regulatory request currently being processed
1361  *
1362  * The Wireless subsystem can use this function to hint to the wireless core
1363  * what it believes should be the current regulatory domain.
1364  *
1365  * Returns zero if all went fine, %-EALREADY if a regulatory domain had
1366  * already been set or other standard error codes.
1367  *
1368  * Caller must hold &cfg80211_mutex and &reg_mutex
1369  */
1370 static int __regulatory_hint(struct wiphy *wiphy,
1371                              struct regulatory_request *pending_request)
1372 {
1373         bool intersect = false;
1374         int r = 0;
1375
1376         assert_cfg80211_lock();
1377
1378         r = ignore_request(wiphy, pending_request);
1379
1380         if (r == REG_INTERSECT) {
1381                 if (pending_request->initiator ==
1382                     NL80211_REGDOM_SET_BY_DRIVER) {
1383                         r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1384                         if (r) {
1385                                 kfree(pending_request);
1386                                 return r;
1387                         }
1388                 }
1389                 intersect = true;
1390         } else if (r) {
1391                 /*
1392                  * If the regulatory domain being requested by the
1393                  * driver has already been set just copy it to the
1394                  * wiphy
1395                  */
1396                 if (r == -EALREADY &&
1397                     pending_request->initiator ==
1398                     NL80211_REGDOM_SET_BY_DRIVER) {
1399                         r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1400                         if (r) {
1401                                 kfree(pending_request);
1402                                 return r;
1403                         }
1404                         r = -EALREADY;
1405                         goto new_request;
1406                 }
1407                 kfree(pending_request);
1408                 return r;
1409         }
1410
1411 new_request:
1412         kfree(last_request);
1413
1414         last_request = pending_request;
1415         last_request->intersect = intersect;
1416
1417         pending_request = NULL;
1418
1419         if (last_request->initiator == NL80211_REGDOM_SET_BY_USER) {
1420                 user_alpha2[0] = last_request->alpha2[0];
1421                 user_alpha2[1] = last_request->alpha2[1];
1422         }
1423
1424         /* When r == REG_INTERSECT we do need to call CRDA */
1425         if (r < 0) {
1426                 /*
1427                  * Since CRDA will not be called in this case as we already
1428                  * have applied the requested regulatory domain before we just
1429                  * inform userspace we have processed the request
1430                  */
1431                 if (r == -EALREADY) {
1432                         nl80211_send_reg_change_event(last_request);
1433                         reg_set_request_processed();
1434                 }
1435                 return r;
1436         }
1437
1438         return call_crda(last_request->alpha2);
1439 }
1440
1441 /* This processes *all* regulatory hints */
1442 static void reg_process_hint(struct regulatory_request *reg_request)
1443 {
1444         int r = 0;
1445         struct wiphy *wiphy = NULL;
1446         enum nl80211_reg_initiator initiator = reg_request->initiator;
1447
1448         BUG_ON(!reg_request->alpha2);
1449
1450         if (wiphy_idx_valid(reg_request->wiphy_idx))
1451                 wiphy = wiphy_idx_to_wiphy(reg_request->wiphy_idx);
1452
1453         if (reg_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1454             !wiphy) {
1455                 kfree(reg_request);
1456                 return;
1457         }
1458
1459         r = __regulatory_hint(wiphy, reg_request);
1460         /* This is required so that the orig_* parameters are saved */
1461         if (r == -EALREADY && wiphy &&
1462             wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY) {
1463                 wiphy_update_regulatory(wiphy, initiator);
1464                 return;
1465         }
1466
1467         /*
1468          * We only time out user hints, given that they should be the only
1469          * source of bogus requests.
1470          */
1471         if (r != -EALREADY &&
1472             reg_request->initiator == NL80211_REGDOM_SET_BY_USER)
1473                 schedule_delayed_work(&reg_timeout, msecs_to_jiffies(3142));
1474 }
1475
1476 /*
1477  * Processes regulatory hints, this is all the NL80211_REGDOM_SET_BY_*
1478  * Regulatory hints come on a first come first serve basis and we
1479  * must process each one atomically.
1480  */
1481 static void reg_process_pending_hints(void)
1482 {
1483         struct regulatory_request *reg_request;
1484
1485         mutex_lock(&cfg80211_mutex);
1486         mutex_lock(&reg_mutex);
1487
1488         /* When last_request->processed becomes true this will be rescheduled */
1489         if (last_request && !last_request->processed) {
1490                 REG_DBG_PRINT("Pending regulatory request, waiting "
1491                               "for it to be processed...\n");
1492                 goto out;
1493         }
1494
1495         spin_lock(&reg_requests_lock);
1496
1497         if (list_empty(&reg_requests_list)) {
1498                 spin_unlock(&reg_requests_lock);
1499                 goto out;
1500         }
1501
1502         reg_request = list_first_entry(&reg_requests_list,
1503                                        struct regulatory_request,
1504                                        list);
1505         list_del_init(&reg_request->list);
1506
1507         spin_unlock(&reg_requests_lock);
1508
1509         reg_process_hint(reg_request);
1510
1511 out:
1512         mutex_unlock(&reg_mutex);
1513         mutex_unlock(&cfg80211_mutex);
1514 }
1515
1516 /* Processes beacon hints -- this has nothing to do with country IEs */
1517 static void reg_process_pending_beacon_hints(void)
1518 {
1519         struct cfg80211_registered_device *rdev;
1520         struct reg_beacon *pending_beacon, *tmp;
1521
1522         /*
1523          * No need to hold the reg_mutex here as we just touch wiphys
1524          * and do not read or access regulatory variables.
1525          */
1526         mutex_lock(&cfg80211_mutex);
1527
1528         /* This goes through the _pending_ beacon list */
1529         spin_lock_bh(&reg_pending_beacons_lock);
1530
1531         if (list_empty(&reg_pending_beacons)) {
1532                 spin_unlock_bh(&reg_pending_beacons_lock);
1533                 goto out;
1534         }
1535
1536         list_for_each_entry_safe(pending_beacon, tmp,
1537                                  &reg_pending_beacons, list) {
1538
1539                 list_del_init(&pending_beacon->list);
1540
1541                 /* Applies the beacon hint to current wiphys */
1542                 list_for_each_entry(rdev, &cfg80211_rdev_list, list)
1543                         wiphy_update_new_beacon(&rdev->wiphy, pending_beacon);
1544
1545                 /* Remembers the beacon hint for new wiphys or reg changes */
1546                 list_add_tail(&pending_beacon->list, &reg_beacon_list);
1547         }
1548
1549         spin_unlock_bh(&reg_pending_beacons_lock);
1550 out:
1551         mutex_unlock(&cfg80211_mutex);
1552 }
1553
1554 static void reg_todo(struct work_struct *work)
1555 {
1556         reg_process_pending_hints();
1557         reg_process_pending_beacon_hints();
1558 }
1559
1560 static void queue_regulatory_request(struct regulatory_request *request)
1561 {
1562         if (isalpha(request->alpha2[0]))
1563                 request->alpha2[0] = toupper(request->alpha2[0]);
1564         if (isalpha(request->alpha2[1]))
1565                 request->alpha2[1] = toupper(request->alpha2[1]);
1566
1567         spin_lock(&reg_requests_lock);
1568         list_add_tail(&request->list, &reg_requests_list);
1569         spin_unlock(&reg_requests_lock);
1570
1571         schedule_work(&reg_work);
1572 }
1573
1574 /*
1575  * Core regulatory hint -- happens during cfg80211_init()
1576  * and when we restore regulatory settings.
1577  */
1578 static int regulatory_hint_core(const char *alpha2)
1579 {
1580         struct regulatory_request *request;
1581
1582         kfree(last_request);
1583         last_request = NULL;
1584
1585         request = kzalloc(sizeof(struct regulatory_request),
1586                           GFP_KERNEL);
1587         if (!request)
1588                 return -ENOMEM;
1589
1590         request->alpha2[0] = alpha2[0];
1591         request->alpha2[1] = alpha2[1];
1592         request->initiator = NL80211_REGDOM_SET_BY_CORE;
1593
1594         queue_regulatory_request(request);
1595
1596         return 0;
1597 }
1598
1599 /* User hints */
1600 int regulatory_hint_user(const char *alpha2)
1601 {
1602         struct regulatory_request *request;
1603
1604         BUG_ON(!alpha2);
1605
1606         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1607         if (!request)
1608                 return -ENOMEM;
1609
1610         request->wiphy_idx = WIPHY_IDX_STALE;
1611         request->alpha2[0] = alpha2[0];
1612         request->alpha2[1] = alpha2[1];
1613         request->initiator = NL80211_REGDOM_SET_BY_USER;
1614
1615         queue_regulatory_request(request);
1616
1617         return 0;
1618 }
1619
1620 /* Driver hints */
1621 int regulatory_hint(struct wiphy *wiphy, const char *alpha2)
1622 {
1623         struct regulatory_request *request;
1624
1625         BUG_ON(!alpha2);
1626         BUG_ON(!wiphy);
1627
1628         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1629         if (!request)
1630                 return -ENOMEM;
1631
1632         request->wiphy_idx = get_wiphy_idx(wiphy);
1633
1634         /* Must have registered wiphy first */
1635         BUG_ON(!wiphy_idx_valid(request->wiphy_idx));
1636
1637         request->alpha2[0] = alpha2[0];
1638         request->alpha2[1] = alpha2[1];
1639         request->initiator = NL80211_REGDOM_SET_BY_DRIVER;
1640
1641         queue_regulatory_request(request);
1642
1643         return 0;
1644 }
1645 EXPORT_SYMBOL(regulatory_hint);
1646
1647 /*
1648  * We hold wdev_lock() here so we cannot hold cfg80211_mutex() and
1649  * therefore cannot iterate over the rdev list here.
1650  */
1651 void regulatory_hint_11d(struct wiphy *wiphy,
1652                          enum ieee80211_band band,
1653                          u8 *country_ie,
1654                          u8 country_ie_len)
1655 {
1656         char alpha2[2];
1657         enum environment_cap env = ENVIRON_ANY;
1658         struct regulatory_request *request;
1659
1660         mutex_lock(&reg_mutex);
1661
1662         if (unlikely(!last_request))
1663                 goto out;
1664
1665         /* IE len must be evenly divisible by 2 */
1666         if (country_ie_len & 0x01)
1667                 goto out;
1668
1669         if (country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN)
1670                 goto out;
1671
1672         alpha2[0] = country_ie[0];
1673         alpha2[1] = country_ie[1];
1674
1675         if (country_ie[2] == 'I')
1676                 env = ENVIRON_INDOOR;
1677         else if (country_ie[2] == 'O')
1678                 env = ENVIRON_OUTDOOR;
1679
1680         /*
1681          * We will run this only upon a successful connection on cfg80211.
1682          * We leave conflict resolution to the workqueue, where can hold
1683          * cfg80211_mutex.
1684          */
1685         if (likely(last_request->initiator ==
1686             NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1687             wiphy_idx_valid(last_request->wiphy_idx)))
1688                 goto out;
1689
1690         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1691         if (!request)
1692                 goto out;
1693
1694         request->wiphy_idx = get_wiphy_idx(wiphy);
1695         request->alpha2[0] = alpha2[0];
1696         request->alpha2[1] = alpha2[1];
1697         request->initiator = NL80211_REGDOM_SET_BY_COUNTRY_IE;
1698         request->country_ie_env = env;
1699
1700         mutex_unlock(&reg_mutex);
1701
1702         queue_regulatory_request(request);
1703
1704         return;
1705
1706 out:
1707         mutex_unlock(&reg_mutex);
1708 }
1709
1710 static void restore_alpha2(char *alpha2, bool reset_user)
1711 {
1712         /* indicates there is no alpha2 to consider for restoration */
1713         alpha2[0] = '9';
1714         alpha2[1] = '7';
1715
1716         /* The user setting has precedence over the module parameter */
1717         if (is_user_regdom_saved()) {
1718                 /* Unless we're asked to ignore it and reset it */
1719                 if (reset_user) {
1720                         REG_DBG_PRINT("Restoring regulatory settings "
1721                                "including user preference\n");
1722                         user_alpha2[0] = '9';
1723                         user_alpha2[1] = '7';
1724
1725                         /*
1726                          * If we're ignoring user settings, we still need to
1727                          * check the module parameter to ensure we put things
1728                          * back as they were for a full restore.
1729                          */
1730                         if (!is_world_regdom(ieee80211_regdom)) {
1731                                 REG_DBG_PRINT("Keeping preference on "
1732                                        "module parameter ieee80211_regdom: %c%c\n",
1733                                        ieee80211_regdom[0],
1734                                        ieee80211_regdom[1]);
1735                                 alpha2[0] = ieee80211_regdom[0];
1736                                 alpha2[1] = ieee80211_regdom[1];
1737                         }
1738                 } else {
1739                         REG_DBG_PRINT("Restoring regulatory settings "
1740                                "while preserving user preference for: %c%c\n",
1741                                user_alpha2[0],
1742                                user_alpha2[1]);
1743                         alpha2[0] = user_alpha2[0];
1744                         alpha2[1] = user_alpha2[1];
1745                 }
1746         } else if (!is_world_regdom(ieee80211_regdom)) {
1747                 REG_DBG_PRINT("Keeping preference on "
1748                        "module parameter ieee80211_regdom: %c%c\n",
1749                        ieee80211_regdom[0],
1750                        ieee80211_regdom[1]);
1751                 alpha2[0] = ieee80211_regdom[0];
1752                 alpha2[1] = ieee80211_regdom[1];
1753         } else
1754                 REG_DBG_PRINT("Restoring regulatory settings\n");
1755 }
1756
1757 /*
1758  * Restoring regulatory settings involves ingoring any
1759  * possibly stale country IE information and user regulatory
1760  * settings if so desired, this includes any beacon hints
1761  * learned as we could have traveled outside to another country
1762  * after disconnection. To restore regulatory settings we do
1763  * exactly what we did at bootup:
1764  *
1765  *   - send a core regulatory hint
1766  *   - send a user regulatory hint if applicable
1767  *
1768  * Device drivers that send a regulatory hint for a specific country
1769  * keep their own regulatory domain on wiphy->regd so that does does
1770  * not need to be remembered.
1771  */
1772 static void restore_regulatory_settings(bool reset_user)
1773 {
1774         char alpha2[2];
1775         struct reg_beacon *reg_beacon, *btmp;
1776         struct regulatory_request *reg_request, *tmp;
1777         LIST_HEAD(tmp_reg_req_list);
1778
1779         mutex_lock(&cfg80211_mutex);
1780         mutex_lock(&reg_mutex);
1781
1782         reset_regdomains();
1783         restore_alpha2(alpha2, reset_user);
1784
1785         /*
1786          * If there's any pending requests we simply
1787          * stash them to a temporary pending queue and
1788          * add then after we've restored regulatory
1789          * settings.
1790          */
1791         spin_lock(&reg_requests_lock);
1792         if (!list_empty(&reg_requests_list)) {
1793                 list_for_each_entry_safe(reg_request, tmp,
1794                                          &reg_requests_list, list) {
1795                         if (reg_request->initiator !=
1796                             NL80211_REGDOM_SET_BY_USER)
1797                                 continue;
1798                         list_del(&reg_request->list);
1799                         list_add_tail(&reg_request->list, &tmp_reg_req_list);
1800                 }
1801         }
1802         spin_unlock(&reg_requests_lock);
1803
1804         /* Clear beacon hints */
1805         spin_lock_bh(&reg_pending_beacons_lock);
1806         if (!list_empty(&reg_pending_beacons)) {
1807                 list_for_each_entry_safe(reg_beacon, btmp,
1808                                          &reg_pending_beacons, list) {
1809                         list_del(&reg_beacon->list);
1810                         kfree(reg_beacon);
1811                 }
1812         }
1813         spin_unlock_bh(&reg_pending_beacons_lock);
1814
1815         if (!list_empty(&reg_beacon_list)) {
1816                 list_for_each_entry_safe(reg_beacon, btmp,
1817                                          &reg_beacon_list, list) {
1818                         list_del(&reg_beacon->list);
1819                         kfree(reg_beacon);
1820                 }
1821         }
1822
1823         /* First restore to the basic regulatory settings */
1824         cfg80211_regdomain = cfg80211_world_regdom;
1825
1826         mutex_unlock(&reg_mutex);
1827         mutex_unlock(&cfg80211_mutex);
1828
1829         regulatory_hint_core(cfg80211_regdomain->alpha2);
1830
1831         /*
1832          * This restores the ieee80211_regdom module parameter
1833          * preference or the last user requested regulatory
1834          * settings, user regulatory settings takes precedence.
1835          */
1836         if (is_an_alpha2(alpha2))
1837                 regulatory_hint_user(user_alpha2);
1838
1839         if (list_empty(&tmp_reg_req_list))
1840                 return;
1841
1842         mutex_lock(&cfg80211_mutex);
1843         mutex_lock(&reg_mutex);
1844
1845         spin_lock(&reg_requests_lock);
1846         list_for_each_entry_safe(reg_request, tmp, &tmp_reg_req_list, list) {
1847                 REG_DBG_PRINT("Adding request for country %c%c back "
1848                               "into the queue\n",
1849                               reg_request->alpha2[0],
1850                               reg_request->alpha2[1]);
1851                 list_del(&reg_request->list);
1852                 list_add_tail(&reg_request->list, &reg_requests_list);
1853         }
1854         spin_unlock(&reg_requests_lock);
1855
1856         mutex_unlock(&reg_mutex);
1857         mutex_unlock(&cfg80211_mutex);
1858
1859         REG_DBG_PRINT("Kicking the queue\n");
1860
1861         schedule_work(&reg_work);
1862 }
1863
1864 void regulatory_hint_disconnect(void)
1865 {
1866         REG_DBG_PRINT("All devices are disconnected, going to "
1867                       "restore regulatory settings\n");
1868         restore_regulatory_settings(false);
1869 }
1870
1871 static bool freq_is_chan_12_13_14(u16 freq)
1872 {
1873         if (freq == ieee80211_channel_to_frequency(12, IEEE80211_BAND_2GHZ) ||
1874             freq == ieee80211_channel_to_frequency(13, IEEE80211_BAND_2GHZ) ||
1875             freq == ieee80211_channel_to_frequency(14, IEEE80211_BAND_2GHZ))
1876                 return true;
1877         return false;
1878 }
1879
1880 int regulatory_hint_found_beacon(struct wiphy *wiphy,
1881                                  struct ieee80211_channel *beacon_chan,
1882                                  gfp_t gfp)
1883 {
1884         struct reg_beacon *reg_beacon;
1885
1886         if (likely((beacon_chan->beacon_found ||
1887             (beacon_chan->flags & IEEE80211_CHAN_RADAR) ||
1888             (beacon_chan->band == IEEE80211_BAND_2GHZ &&
1889              !freq_is_chan_12_13_14(beacon_chan->center_freq)))))
1890                 return 0;
1891
1892         reg_beacon = kzalloc(sizeof(struct reg_beacon), gfp);
1893         if (!reg_beacon)
1894                 return -ENOMEM;
1895
1896         REG_DBG_PRINT("Found new beacon on "
1897                       "frequency: %d MHz (Ch %d) on %s\n",
1898                       beacon_chan->center_freq,
1899                       ieee80211_frequency_to_channel(beacon_chan->center_freq),
1900                       wiphy_name(wiphy));
1901
1902         memcpy(&reg_beacon->chan, beacon_chan,
1903                 sizeof(struct ieee80211_channel));
1904
1905
1906         /*
1907          * Since we can be called from BH or and non-BH context
1908          * we must use spin_lock_bh()
1909          */
1910         spin_lock_bh(&reg_pending_beacons_lock);
1911         list_add_tail(&reg_beacon->list, &reg_pending_beacons);
1912         spin_unlock_bh(&reg_pending_beacons_lock);
1913
1914         schedule_work(&reg_work);
1915
1916         return 0;
1917 }
1918
1919 static void print_rd_rules(const struct ieee80211_regdomain *rd)
1920 {
1921         unsigned int i;
1922         const struct ieee80211_reg_rule *reg_rule = NULL;
1923         const struct ieee80211_freq_range *freq_range = NULL;
1924         const struct ieee80211_power_rule *power_rule = NULL;
1925
1926         pr_info("    (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)\n");
1927
1928         for (i = 0; i < rd->n_reg_rules; i++) {
1929                 reg_rule = &rd->reg_rules[i];
1930                 freq_range = &reg_rule->freq_range;
1931                 power_rule = &reg_rule->power_rule;
1932
1933                 /*
1934                  * There may not be documentation for max antenna gain
1935                  * in certain regions
1936                  */
1937                 if (power_rule->max_antenna_gain)
1938                         pr_info("    (%d KHz - %d KHz @ %d KHz), (%d mBi, %d mBm)\n",
1939                                 freq_range->start_freq_khz,
1940                                 freq_range->end_freq_khz,
1941                                 freq_range->max_bandwidth_khz,
1942                                 power_rule->max_antenna_gain,
1943                                 power_rule->max_eirp);
1944                 else
1945                         pr_info("    (%d KHz - %d KHz @ %d KHz), (N/A, %d mBm)\n",
1946                                 freq_range->start_freq_khz,
1947                                 freq_range->end_freq_khz,
1948                                 freq_range->max_bandwidth_khz,
1949                                 power_rule->max_eirp);
1950         }
1951 }
1952
1953 bool reg_supported_dfs_region(u8 dfs_region)
1954 {
1955         switch (dfs_region) {
1956         case NL80211_DFS_UNSET:
1957         case NL80211_DFS_FCC:
1958         case NL80211_DFS_ETSI:
1959         case NL80211_DFS_JP:
1960                 return true;
1961         default:
1962                 REG_DBG_PRINT("Ignoring uknown DFS master region: %d\n",
1963                               dfs_region);
1964                 return false;
1965         }
1966 }
1967
1968 static void print_dfs_region(u8 dfs_region)
1969 {
1970         if (!dfs_region)
1971                 return;
1972
1973         switch (dfs_region) {
1974         case NL80211_DFS_FCC:
1975                 pr_info(" DFS Master region FCC");
1976                 break;
1977         case NL80211_DFS_ETSI:
1978                 pr_info(" DFS Master region ETSI");
1979                 break;
1980         case NL80211_DFS_JP:
1981                 pr_info(" DFS Master region JP");
1982                 break;
1983         default:
1984                 pr_info(" DFS Master region Uknown");
1985                 break;
1986         }
1987 }
1988
1989 static void print_regdomain(const struct ieee80211_regdomain *rd)
1990 {
1991
1992         if (is_intersected_alpha2(rd->alpha2)) {
1993
1994                 if (last_request->initiator ==
1995                     NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1996                         struct cfg80211_registered_device *rdev;
1997                         rdev = cfg80211_rdev_by_wiphy_idx(
1998                                 last_request->wiphy_idx);
1999                         if (rdev) {
2000                                 pr_info("Current regulatory domain updated by AP to: %c%c\n",
2001                                         rdev->country_ie_alpha2[0],
2002                                         rdev->country_ie_alpha2[1]);
2003                         } else
2004                                 pr_info("Current regulatory domain intersected:\n");
2005                 } else
2006                         pr_info("Current regulatory domain intersected:\n");
2007         } else if (is_world_regdom(rd->alpha2))
2008                 pr_info("World regulatory domain updated:\n");
2009         else {
2010                 if (is_unknown_alpha2(rd->alpha2))
2011                         pr_info("Regulatory domain changed to driver built-in settings (unknown country)\n");
2012                 else
2013                         pr_info("Regulatory domain changed to country: %c%c\n",
2014                                 rd->alpha2[0], rd->alpha2[1]);
2015         }
2016         print_dfs_region(rd->dfs_region);
2017         print_rd_rules(rd);
2018 }
2019
2020 static void print_regdomain_info(const struct ieee80211_regdomain *rd)
2021 {
2022         pr_info("Regulatory domain: %c%c\n", rd->alpha2[0], rd->alpha2[1]);
2023         print_rd_rules(rd);
2024 }
2025
2026 /* Takes ownership of rd only if it doesn't fail */
2027 static int __set_regdom(const struct ieee80211_regdomain *rd)
2028 {
2029         const struct ieee80211_regdomain *intersected_rd = NULL;
2030         struct cfg80211_registered_device *rdev = NULL;
2031         struct wiphy *request_wiphy;
2032         /* Some basic sanity checks first */
2033
2034         if (is_world_regdom(rd->alpha2)) {
2035                 if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
2036                         return -EINVAL;
2037                 update_world_regdomain(rd);
2038                 return 0;
2039         }
2040
2041         if (!is_alpha2_set(rd->alpha2) && !is_an_alpha2(rd->alpha2) &&
2042                         !is_unknown_alpha2(rd->alpha2))
2043                 return -EINVAL;
2044
2045         if (!last_request)
2046                 return -EINVAL;
2047
2048         /*
2049          * Lets only bother proceeding on the same alpha2 if the current
2050          * rd is non static (it means CRDA was present and was used last)
2051          * and the pending request came in from a country IE
2052          */
2053         if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2054                 /*
2055                  * If someone else asked us to change the rd lets only bother
2056                  * checking if the alpha2 changes if CRDA was already called
2057                  */
2058                 if (!regdom_changes(rd->alpha2))
2059                         return -EINVAL;
2060         }
2061
2062         /*
2063          * Now lets set the regulatory domain, update all driver channels
2064          * and finally inform them of what we have done, in case they want
2065          * to review or adjust their own settings based on their own
2066          * internal EEPROM data
2067          */
2068
2069         if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
2070                 return -EINVAL;
2071
2072         if (!is_valid_rd(rd)) {
2073                 pr_err("Invalid regulatory domain detected:\n");
2074                 print_regdomain_info(rd);
2075                 return -EINVAL;
2076         }
2077
2078         request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
2079
2080         if (!last_request->intersect) {
2081                 int r;
2082
2083                 if (last_request->initiator != NL80211_REGDOM_SET_BY_DRIVER) {
2084                         reset_regdomains();
2085                         cfg80211_regdomain = rd;
2086                         return 0;
2087                 }
2088
2089                 /*
2090                  * For a driver hint, lets copy the regulatory domain the
2091                  * driver wanted to the wiphy to deal with conflicts
2092                  */
2093
2094                 /*
2095                  * Userspace could have sent two replies with only
2096                  * one kernel request.
2097                  */
2098                 if (request_wiphy->regd)
2099                         return -EALREADY;
2100
2101                 r = reg_copy_regd(&request_wiphy->regd, rd);
2102                 if (r)
2103                         return r;
2104
2105                 reset_regdomains();
2106                 cfg80211_regdomain = rd;
2107                 return 0;
2108         }
2109
2110         /* Intersection requires a bit more work */
2111
2112         if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2113
2114                 intersected_rd = regdom_intersect(rd, cfg80211_regdomain);
2115                 if (!intersected_rd)
2116                         return -EINVAL;
2117
2118                 /*
2119                  * We can trash what CRDA provided now.
2120                  * However if a driver requested this specific regulatory
2121                  * domain we keep it for its private use
2122                  */
2123                 if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER)
2124                         request_wiphy->regd = rd;
2125                 else
2126                         kfree(rd);
2127
2128                 rd = NULL;
2129
2130                 reset_regdomains();
2131                 cfg80211_regdomain = intersected_rd;
2132
2133                 return 0;
2134         }
2135
2136         if (!intersected_rd)
2137                 return -EINVAL;
2138
2139         rdev = wiphy_to_dev(request_wiphy);
2140
2141         rdev->country_ie_alpha2[0] = rd->alpha2[0];
2142         rdev->country_ie_alpha2[1] = rd->alpha2[1];
2143         rdev->env = last_request->country_ie_env;
2144
2145         BUG_ON(intersected_rd == rd);
2146
2147         kfree(rd);
2148         rd = NULL;
2149
2150         reset_regdomains();
2151         cfg80211_regdomain = intersected_rd;
2152
2153         return 0;
2154 }
2155
2156
2157 /*
2158  * Use this call to set the current regulatory domain. Conflicts with
2159  * multiple drivers can be ironed out later. Caller must've already
2160  * kmalloc'd the rd structure. Caller must hold cfg80211_mutex
2161  */
2162 int set_regdom(const struct ieee80211_regdomain *rd)
2163 {
2164         int r;
2165
2166         assert_cfg80211_lock();
2167
2168         mutex_lock(&reg_mutex);
2169
2170         /* Note that this doesn't update the wiphys, this is done below */
2171         r = __set_regdom(rd);
2172         if (r) {
2173                 kfree(rd);
2174                 mutex_unlock(&reg_mutex);
2175                 return r;
2176         }
2177
2178         /* This would make this whole thing pointless */
2179         if (!last_request->intersect)
2180                 BUG_ON(rd != cfg80211_regdomain);
2181
2182         /* update all wiphys now with the new established regulatory domain */
2183         update_all_wiphy_regulatory(last_request->initiator);
2184
2185         print_regdomain(cfg80211_regdomain);
2186
2187         nl80211_send_reg_change_event(last_request);
2188
2189         reg_set_request_processed();
2190
2191         mutex_unlock(&reg_mutex);
2192
2193         return r;
2194 }
2195
2196 #ifdef CONFIG_HOTPLUG
2197 int reg_device_uevent(struct device *dev, struct kobj_uevent_env *env)
2198 {
2199         if (last_request && !last_request->processed) {
2200                 if (add_uevent_var(env, "COUNTRY=%c%c",
2201                                    last_request->alpha2[0],
2202                                    last_request->alpha2[1]))
2203                         return -ENOMEM;
2204         }
2205
2206         return 0;
2207 }
2208 #else
2209 int reg_device_uevent(struct device *dev, struct kobj_uevent_env *env)
2210 {
2211         return -ENODEV;
2212 }
2213 #endif /* CONFIG_HOTPLUG */
2214
2215 /* Caller must hold cfg80211_mutex */
2216 void reg_device_remove(struct wiphy *wiphy)
2217 {
2218         struct wiphy *request_wiphy = NULL;
2219
2220         assert_cfg80211_lock();
2221
2222         mutex_lock(&reg_mutex);
2223
2224         kfree(wiphy->regd);
2225
2226         if (last_request)
2227                 request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
2228
2229         if (!request_wiphy || request_wiphy != wiphy)
2230                 goto out;
2231
2232         last_request->wiphy_idx = WIPHY_IDX_STALE;
2233         last_request->country_ie_env = ENVIRON_ANY;
2234 out:
2235         mutex_unlock(&reg_mutex);
2236 }
2237
2238 static void reg_timeout_work(struct work_struct *work)
2239 {
2240         REG_DBG_PRINT("Timeout while waiting for CRDA to reply, "
2241                       "restoring regulatory settings\n");
2242         restore_regulatory_settings(true);
2243 }
2244
2245 int __init regulatory_init(void)
2246 {
2247         int err = 0;
2248
2249         reg_pdev = platform_device_register_simple("regulatory", 0, NULL, 0);
2250         if (IS_ERR(reg_pdev))
2251                 return PTR_ERR(reg_pdev);
2252
2253         reg_pdev->dev.type = &reg_device_type;
2254
2255         spin_lock_init(&reg_requests_lock);
2256         spin_lock_init(&reg_pending_beacons_lock);
2257
2258         cfg80211_regdomain = cfg80211_world_regdom;
2259
2260         user_alpha2[0] = '9';
2261         user_alpha2[1] = '7';
2262
2263         /* We always try to get an update for the static regdomain */
2264         err = regulatory_hint_core(cfg80211_regdomain->alpha2);
2265         if (err) {
2266                 if (err == -ENOMEM)
2267                         return err;
2268                 /*
2269                  * N.B. kobject_uevent_env() can fail mainly for when we're out
2270                  * memory which is handled and propagated appropriately above
2271                  * but it can also fail during a netlink_broadcast() or during
2272                  * early boot for call_usermodehelper(). For now treat these
2273                  * errors as non-fatal.
2274                  */
2275                 pr_err("kobject_uevent_env() was unable to call CRDA during init\n");
2276 #ifdef CONFIG_CFG80211_REG_DEBUG
2277                 /* We want to find out exactly why when debugging */
2278                 WARN_ON(err);
2279 #endif
2280         }
2281
2282         /*
2283          * Finally, if the user set the module parameter treat it
2284          * as a user hint.
2285          */
2286         if (!is_world_regdom(ieee80211_regdom))
2287                 regulatory_hint_user(ieee80211_regdom);
2288
2289         return 0;
2290 }
2291
2292 void /* __init_or_exit */ regulatory_exit(void)
2293 {
2294         struct regulatory_request *reg_request, *tmp;
2295         struct reg_beacon *reg_beacon, *btmp;
2296
2297         cancel_work_sync(&reg_work);
2298         cancel_delayed_work_sync(&reg_timeout);
2299
2300         mutex_lock(&cfg80211_mutex);
2301         mutex_lock(&reg_mutex);
2302
2303         reset_regdomains();
2304
2305         kfree(last_request);
2306
2307         platform_device_unregister(reg_pdev);
2308
2309         spin_lock_bh(&reg_pending_beacons_lock);
2310         if (!list_empty(&reg_pending_beacons)) {
2311                 list_for_each_entry_safe(reg_beacon, btmp,
2312                                          &reg_pending_beacons, list) {
2313                         list_del(&reg_beacon->list);
2314                         kfree(reg_beacon);
2315                 }
2316         }
2317         spin_unlock_bh(&reg_pending_beacons_lock);
2318
2319         if (!list_empty(&reg_beacon_list)) {
2320                 list_for_each_entry_safe(reg_beacon, btmp,
2321                                          &reg_beacon_list, list) {
2322                         list_del(&reg_beacon->list);
2323                         kfree(reg_beacon);
2324                 }
2325         }
2326
2327         spin_lock(&reg_requests_lock);
2328         if (!list_empty(&reg_requests_list)) {
2329                 list_for_each_entry_safe(reg_request, tmp,
2330                                          &reg_requests_list, list) {
2331                         list_del(&reg_request->list);
2332                         kfree(reg_request);
2333                 }
2334         }
2335         spin_unlock(&reg_requests_lock);
2336
2337         mutex_unlock(&reg_mutex);
2338         mutex_unlock(&cfg80211_mutex);
2339 }