1bc36d250baf076b6acd64df413d112d4ce014a3
[linux-2.6.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/slab.h>
40 #include <linux/list.h>
41 #include <linux/random.h>
42 #include <linux/ctype.h>
43 #include <linux/nl80211.h>
44 #include <linux/platform_device.h>
45 #include <net/cfg80211.h>
46 #include "core.h"
47 #include "reg.h"
48 #include "regdb.h"
49 #include "nl80211.h"
50
51 #ifdef CONFIG_CFG80211_REG_DEBUG
52 #define REG_DBG_PRINT(format, args...) \
53         do { \
54                 printk(KERN_DEBUG pr_fmt(format), ##args);      \
55         } while (0)
56 #else
57 #define REG_DBG_PRINT(args...)
58 #endif
59
60 static struct regulatory_request core_request_world = {
61         .initiator = NL80211_REGDOM_SET_BY_CORE,
62         .alpha2[0] = '0',
63         .alpha2[1] = '0',
64         .intersect = false,
65         .processed = true,
66         .country_ie_env = ENVIRON_ANY,
67 };
68
69 /* Receipt of information from last regulatory request */
70 static struct regulatory_request *last_request = &core_request_world;
71
72 /* To trigger userspace events */
73 static struct platform_device *reg_pdev;
74
75 static struct device_type reg_device_type = {
76         .uevent = reg_device_uevent,
77 };
78
79 /*
80  * Central wireless core regulatory domains, we only need two,
81  * the current one and a world regulatory domain in case we have no
82  * information to give us an alpha2
83  */
84 const struct ieee80211_regdomain *cfg80211_regdomain;
85
86 /*
87  * Protects static reg.c components:
88  *     - cfg80211_world_regdom
89  *     - cfg80211_regdom
90  *     - last_request
91  */
92 static DEFINE_MUTEX(reg_mutex);
93
94 static inline void assert_reg_lock(void)
95 {
96         lockdep_assert_held(&reg_mutex);
97 }
98
99 /* Used to queue up regulatory hints */
100 static LIST_HEAD(reg_requests_list);
101 static spinlock_t reg_requests_lock;
102
103 /* Used to queue up beacon hints for review */
104 static LIST_HEAD(reg_pending_beacons);
105 static spinlock_t reg_pending_beacons_lock;
106
107 /* Used to keep track of processed beacon hints */
108 static LIST_HEAD(reg_beacon_list);
109
110 struct reg_beacon {
111         struct list_head list;
112         struct ieee80211_channel chan;
113 };
114
115 static void reg_todo(struct work_struct *work);
116 static DECLARE_WORK(reg_work, reg_todo);
117
118 static void reg_timeout_work(struct work_struct *work);
119 static DECLARE_DELAYED_WORK(reg_timeout, reg_timeout_work);
120
121 /* We keep a static world regulatory domain in case of the absence of CRDA */
122 static const struct ieee80211_regdomain world_regdom = {
123         .n_reg_rules = 5,
124         .alpha2 =  "00",
125         .reg_rules = {
126                 /* IEEE 802.11b/g, channels 1..11 */
127                 REG_RULE(2412-10, 2462+10, 40, 6, 20, 0),
128                 /* IEEE 802.11b/g, channels 12..13. No HT40
129                  * channel fits here. */
130                 REG_RULE(2467-10, 2472+10, 20, 6, 20,
131                         NL80211_RRF_PASSIVE_SCAN |
132                         NL80211_RRF_NO_IBSS),
133                 /* IEEE 802.11 channel 14 - Only JP enables
134                  * this and for 802.11b only */
135                 REG_RULE(2484-10, 2484+10, 20, 6, 20,
136                         NL80211_RRF_PASSIVE_SCAN |
137                         NL80211_RRF_NO_IBSS |
138                         NL80211_RRF_NO_OFDM),
139                 /* IEEE 802.11a, channel 36..48 */
140                 REG_RULE(5180-10, 5240+10, 40, 6, 20,
141                         NL80211_RRF_PASSIVE_SCAN |
142                         NL80211_RRF_NO_IBSS),
143
144                 /* NB: 5260 MHz - 5700 MHz requies DFS */
145
146                 /* IEEE 802.11a, channel 149..165 */
147                 REG_RULE(5745-10, 5825+10, 40, 6, 20,
148                         NL80211_RRF_PASSIVE_SCAN |
149                         NL80211_RRF_NO_IBSS),
150         }
151 };
152
153 static const struct ieee80211_regdomain *cfg80211_world_regdom =
154         &world_regdom;
155
156 static char *ieee80211_regdom = "00";
157 static char user_alpha2[2];
158
159 module_param(ieee80211_regdom, charp, 0444);
160 MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain code");
161
162 static void reset_regdomains(bool full_reset)
163 {
164         /* avoid freeing static information or freeing something twice */
165         if (cfg80211_regdomain == cfg80211_world_regdom)
166                 cfg80211_regdomain = NULL;
167         if (cfg80211_world_regdom == &world_regdom)
168                 cfg80211_world_regdom = NULL;
169         if (cfg80211_regdomain == &world_regdom)
170                 cfg80211_regdomain = NULL;
171
172         kfree(cfg80211_regdomain);
173         kfree(cfg80211_world_regdom);
174
175         cfg80211_world_regdom = &world_regdom;
176         cfg80211_regdomain = NULL;
177
178         if (!full_reset)
179                 return;
180
181         if (last_request != &core_request_world)
182                 kfree(last_request);
183         last_request = &core_request_world;
184 }
185
186 /*
187  * Dynamic world regulatory domain requested by the wireless
188  * core upon initialization
189  */
190 static void update_world_regdomain(const struct ieee80211_regdomain *rd)
191 {
192         BUG_ON(!last_request);
193
194         reset_regdomains(false);
195
196         cfg80211_world_regdom = rd;
197         cfg80211_regdomain = rd;
198 }
199
200 bool is_world_regdom(const char *alpha2)
201 {
202         if (!alpha2)
203                 return false;
204         if (alpha2[0] == '0' && alpha2[1] == '0')
205                 return true;
206         return false;
207 }
208
209 static bool is_alpha2_set(const char *alpha2)
210 {
211         if (!alpha2)
212                 return false;
213         if (alpha2[0] != 0 && alpha2[1] != 0)
214                 return true;
215         return false;
216 }
217
218 static bool is_unknown_alpha2(const char *alpha2)
219 {
220         if (!alpha2)
221                 return false;
222         /*
223          * Special case where regulatory domain was built by driver
224          * but a specific alpha2 cannot be determined
225          */
226         if (alpha2[0] == '9' && alpha2[1] == '9')
227                 return true;
228         return false;
229 }
230
231 static bool is_intersected_alpha2(const char *alpha2)
232 {
233         if (!alpha2)
234                 return false;
235         /*
236          * Special case where regulatory domain is the
237          * result of an intersection between two regulatory domain
238          * structures
239          */
240         if (alpha2[0] == '9' && alpha2[1] == '8')
241                 return true;
242         return false;
243 }
244
245 static bool is_an_alpha2(const char *alpha2)
246 {
247         if (!alpha2)
248                 return false;
249         if (isalpha(alpha2[0]) && isalpha(alpha2[1]))
250                 return true;
251         return false;
252 }
253
254 static bool alpha2_equal(const char *alpha2_x, const char *alpha2_y)
255 {
256         if (!alpha2_x || !alpha2_y)
257                 return false;
258         if (alpha2_x[0] == alpha2_y[0] &&
259                 alpha2_x[1] == alpha2_y[1])
260                 return true;
261         return false;
262 }
263
264 static bool regdom_changes(const char *alpha2)
265 {
266         assert_cfg80211_lock();
267
268         if (!cfg80211_regdomain)
269                 return true;
270         if (alpha2_equal(cfg80211_regdomain->alpha2, alpha2))
271                 return false;
272         return true;
273 }
274
275 /*
276  * The NL80211_REGDOM_SET_BY_USER regdom alpha2 is cached, this lets
277  * you know if a valid regulatory hint with NL80211_REGDOM_SET_BY_USER
278  * has ever been issued.
279  */
280 static bool is_user_regdom_saved(void)
281 {
282         if (user_alpha2[0] == '9' && user_alpha2[1] == '7')
283                 return false;
284
285         /* This would indicate a mistake on the design */
286         if (WARN((!is_world_regdom(user_alpha2) &&
287                   !is_an_alpha2(user_alpha2)),
288                  "Unexpected user alpha2: %c%c\n",
289                  user_alpha2[0],
290                  user_alpha2[1]))
291                 return false;
292
293         return true;
294 }
295
296 static int reg_copy_regd(const struct ieee80211_regdomain **dst_regd,
297                          const struct ieee80211_regdomain *src_regd)
298 {
299         struct ieee80211_regdomain *regd;
300         int size_of_regd = 0;
301         unsigned int i;
302
303         size_of_regd = sizeof(struct ieee80211_regdomain) +
304           ((src_regd->n_reg_rules + 1) * sizeof(struct ieee80211_reg_rule));
305
306         regd = kzalloc(size_of_regd, GFP_KERNEL);
307         if (!regd)
308                 return -ENOMEM;
309
310         memcpy(regd, src_regd, sizeof(struct ieee80211_regdomain));
311
312         for (i = 0; i < src_regd->n_reg_rules; i++)
313                 memcpy(&regd->reg_rules[i], &src_regd->reg_rules[i],
314                         sizeof(struct ieee80211_reg_rule));
315
316         *dst_regd = regd;
317         return 0;
318 }
319
320 #ifdef CONFIG_CFG80211_INTERNAL_REGDB
321 struct reg_regdb_search_request {
322         char alpha2[2];
323         struct list_head list;
324 };
325
326 static LIST_HEAD(reg_regdb_search_list);
327 static DEFINE_MUTEX(reg_regdb_search_mutex);
328
329 static void reg_regdb_search(struct work_struct *work)
330 {
331         struct reg_regdb_search_request *request;
332         const struct ieee80211_regdomain *curdom, *regdom;
333         int i, r;
334
335         mutex_lock(&reg_regdb_search_mutex);
336         while (!list_empty(&reg_regdb_search_list)) {
337                 request = list_first_entry(&reg_regdb_search_list,
338                                            struct reg_regdb_search_request,
339                                            list);
340                 list_del(&request->list);
341
342                 for (i=0; i<reg_regdb_size; i++) {
343                         curdom = reg_regdb[i];
344
345                         if (!memcmp(request->alpha2, curdom->alpha2, 2)) {
346                                 r = reg_copy_regd(&regdom, curdom);
347                                 if (r)
348                                         break;
349                                 mutex_lock(&cfg80211_mutex);
350                                 set_regdom(regdom);
351                                 mutex_unlock(&cfg80211_mutex);
352                                 break;
353                         }
354                 }
355
356                 kfree(request);
357         }
358         mutex_unlock(&reg_regdb_search_mutex);
359 }
360
361 static DECLARE_WORK(reg_regdb_work, reg_regdb_search);
362
363 static void reg_regdb_query(const char *alpha2)
364 {
365         struct reg_regdb_search_request *request;
366
367         if (!alpha2)
368                 return;
369
370         request = kzalloc(sizeof(struct reg_regdb_search_request), GFP_KERNEL);
371         if (!request)
372                 return;
373
374         memcpy(request->alpha2, alpha2, 2);
375
376         mutex_lock(&reg_regdb_search_mutex);
377         list_add_tail(&request->list, &reg_regdb_search_list);
378         mutex_unlock(&reg_regdb_search_mutex);
379
380         schedule_work(&reg_regdb_work);
381 }
382 #else
383 static inline void reg_regdb_query(const char *alpha2) {}
384 #endif /* CONFIG_CFG80211_INTERNAL_REGDB */
385
386 /*
387  * This lets us keep regulatory code which is updated on a regulatory
388  * basis in userspace. Country information is filled in by
389  * reg_device_uevent
390  */
391 static int call_crda(const char *alpha2)
392 {
393         if (!is_world_regdom((char *) alpha2))
394                 pr_info("Calling CRDA for country: %c%c\n",
395                         alpha2[0], alpha2[1]);
396         else
397                 pr_info("Calling CRDA to update world regulatory domain\n");
398
399         /* query internal regulatory database (if it exists) */
400         reg_regdb_query(alpha2);
401
402         return kobject_uevent(&reg_pdev->dev.kobj, KOBJ_CHANGE);
403 }
404
405 /* Used by nl80211 before kmalloc'ing our regulatory domain */
406 bool reg_is_valid_request(const char *alpha2)
407 {
408         assert_cfg80211_lock();
409
410         if (!last_request)
411                 return false;
412
413         return alpha2_equal(last_request->alpha2, alpha2);
414 }
415
416 /* Sanity check on a regulatory rule */
417 static bool is_valid_reg_rule(const struct ieee80211_reg_rule *rule)
418 {
419         const struct ieee80211_freq_range *freq_range = &rule->freq_range;
420         u32 freq_diff;
421
422         if (freq_range->start_freq_khz <= 0 || freq_range->end_freq_khz <= 0)
423                 return false;
424
425         if (freq_range->start_freq_khz > freq_range->end_freq_khz)
426                 return false;
427
428         freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
429
430         if (freq_range->end_freq_khz <= freq_range->start_freq_khz ||
431                         freq_range->max_bandwidth_khz > freq_diff)
432                 return false;
433
434         return true;
435 }
436
437 static bool is_valid_rd(const struct ieee80211_regdomain *rd)
438 {
439         const struct ieee80211_reg_rule *reg_rule = NULL;
440         unsigned int i;
441
442         if (!rd->n_reg_rules)
443                 return false;
444
445         if (WARN_ON(rd->n_reg_rules > NL80211_MAX_SUPP_REG_RULES))
446                 return false;
447
448         for (i = 0; i < rd->n_reg_rules; i++) {
449                 reg_rule = &rd->reg_rules[i];
450                 if (!is_valid_reg_rule(reg_rule))
451                         return false;
452         }
453
454         return true;
455 }
456
457 static bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_range,
458                             u32 center_freq_khz,
459                             u32 bw_khz)
460 {
461         u32 start_freq_khz, end_freq_khz;
462
463         start_freq_khz = center_freq_khz - (bw_khz/2);
464         end_freq_khz = center_freq_khz + (bw_khz/2);
465
466         if (start_freq_khz >= freq_range->start_freq_khz &&
467             end_freq_khz <= freq_range->end_freq_khz)
468                 return true;
469
470         return false;
471 }
472
473 /**
474  * freq_in_rule_band - tells us if a frequency is in a frequency band
475  * @freq_range: frequency rule we want to query
476  * @freq_khz: frequency we are inquiring about
477  *
478  * This lets us know if a specific frequency rule is or is not relevant to
479  * a specific frequency's band. Bands are device specific and artificial
480  * definitions (the "2.4 GHz band" and the "5 GHz band"), however it is
481  * safe for now to assume that a frequency rule should not be part of a
482  * frequency's band if the start freq or end freq are off by more than 2 GHz.
483  * This resolution can be lowered and should be considered as we add
484  * regulatory rule support for other "bands".
485  **/
486 static bool freq_in_rule_band(const struct ieee80211_freq_range *freq_range,
487         u32 freq_khz)
488 {
489 #define ONE_GHZ_IN_KHZ  1000000
490         if (abs(freq_khz - freq_range->start_freq_khz) <= (2 * ONE_GHZ_IN_KHZ))
491                 return true;
492         if (abs(freq_khz - freq_range->end_freq_khz) <= (2 * ONE_GHZ_IN_KHZ))
493                 return true;
494         return false;
495 #undef ONE_GHZ_IN_KHZ
496 }
497
498 /*
499  * Helper for regdom_intersect(), this does the real
500  * mathematical intersection fun
501  */
502 static int reg_rules_intersect(
503         const struct ieee80211_reg_rule *rule1,
504         const struct ieee80211_reg_rule *rule2,
505         struct ieee80211_reg_rule *intersected_rule)
506 {
507         const struct ieee80211_freq_range *freq_range1, *freq_range2;
508         struct ieee80211_freq_range *freq_range;
509         const struct ieee80211_power_rule *power_rule1, *power_rule2;
510         struct ieee80211_power_rule *power_rule;
511         u32 freq_diff;
512
513         freq_range1 = &rule1->freq_range;
514         freq_range2 = &rule2->freq_range;
515         freq_range = &intersected_rule->freq_range;
516
517         power_rule1 = &rule1->power_rule;
518         power_rule2 = &rule2->power_rule;
519         power_rule = &intersected_rule->power_rule;
520
521         freq_range->start_freq_khz = max(freq_range1->start_freq_khz,
522                 freq_range2->start_freq_khz);
523         freq_range->end_freq_khz = min(freq_range1->end_freq_khz,
524                 freq_range2->end_freq_khz);
525         freq_range->max_bandwidth_khz = min(freq_range1->max_bandwidth_khz,
526                 freq_range2->max_bandwidth_khz);
527
528         freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
529         if (freq_range->max_bandwidth_khz > freq_diff)
530                 freq_range->max_bandwidth_khz = freq_diff;
531
532         power_rule->max_eirp = min(power_rule1->max_eirp,
533                 power_rule2->max_eirp);
534         power_rule->max_antenna_gain = min(power_rule1->max_antenna_gain,
535                 power_rule2->max_antenna_gain);
536
537         intersected_rule->flags = (rule1->flags | rule2->flags);
538
539         if (!is_valid_reg_rule(intersected_rule))
540                 return -EINVAL;
541
542         return 0;
543 }
544
545 /**
546  * regdom_intersect - do the intersection between two regulatory domains
547  * @rd1: first regulatory domain
548  * @rd2: second regulatory domain
549  *
550  * Use this function to get the intersection between two regulatory domains.
551  * Once completed we will mark the alpha2 for the rd as intersected, "98",
552  * as no one single alpha2 can represent this regulatory domain.
553  *
554  * Returns a pointer to the regulatory domain structure which will hold the
555  * resulting intersection of rules between rd1 and rd2. We will
556  * kzalloc() this structure for you.
557  */
558 static struct ieee80211_regdomain *regdom_intersect(
559         const struct ieee80211_regdomain *rd1,
560         const struct ieee80211_regdomain *rd2)
561 {
562         int r, size_of_regd;
563         unsigned int x, y;
564         unsigned int num_rules = 0, rule_idx = 0;
565         const struct ieee80211_reg_rule *rule1, *rule2;
566         struct ieee80211_reg_rule *intersected_rule;
567         struct ieee80211_regdomain *rd;
568         /* This is just a dummy holder to help us count */
569         struct ieee80211_reg_rule irule;
570
571         /* Uses the stack temporarily for counter arithmetic */
572         intersected_rule = &irule;
573
574         memset(intersected_rule, 0, sizeof(struct ieee80211_reg_rule));
575
576         if (!rd1 || !rd2)
577                 return NULL;
578
579         /*
580          * First we get a count of the rules we'll need, then we actually
581          * build them. This is to so we can malloc() and free() a
582          * regdomain once. The reason we use reg_rules_intersect() here
583          * is it will return -EINVAL if the rule computed makes no sense.
584          * All rules that do check out OK are valid.
585          */
586
587         for (x = 0; x < rd1->n_reg_rules; x++) {
588                 rule1 = &rd1->reg_rules[x];
589                 for (y = 0; y < rd2->n_reg_rules; y++) {
590                         rule2 = &rd2->reg_rules[y];
591                         if (!reg_rules_intersect(rule1, rule2,
592                                         intersected_rule))
593                                 num_rules++;
594                         memset(intersected_rule, 0,
595                                         sizeof(struct ieee80211_reg_rule));
596                 }
597         }
598
599         if (!num_rules)
600                 return NULL;
601
602         size_of_regd = sizeof(struct ieee80211_regdomain) +
603                 ((num_rules + 1) * sizeof(struct ieee80211_reg_rule));
604
605         rd = kzalloc(size_of_regd, GFP_KERNEL);
606         if (!rd)
607                 return NULL;
608
609         for (x = 0; x < rd1->n_reg_rules; x++) {
610                 rule1 = &rd1->reg_rules[x];
611                 for (y = 0; y < rd2->n_reg_rules; y++) {
612                         rule2 = &rd2->reg_rules[y];
613                         /*
614                          * This time around instead of using the stack lets
615                          * write to the target rule directly saving ourselves
616                          * a memcpy()
617                          */
618                         intersected_rule = &rd->reg_rules[rule_idx];
619                         r = reg_rules_intersect(rule1, rule2,
620                                 intersected_rule);
621                         /*
622                          * No need to memset here the intersected rule here as
623                          * we're not using the stack anymore
624                          */
625                         if (r)
626                                 continue;
627                         rule_idx++;
628                 }
629         }
630
631         if (rule_idx != num_rules) {
632                 kfree(rd);
633                 return NULL;
634         }
635
636         rd->n_reg_rules = num_rules;
637         rd->alpha2[0] = '9';
638         rd->alpha2[1] = '8';
639
640         return rd;
641 }
642
643 /*
644  * XXX: add support for the rest of enum nl80211_reg_rule_flags, we may
645  * want to just have the channel structure use these
646  */
647 static u32 map_regdom_flags(u32 rd_flags)
648 {
649         u32 channel_flags = 0;
650         if (rd_flags & NL80211_RRF_PASSIVE_SCAN)
651                 channel_flags |= IEEE80211_CHAN_PASSIVE_SCAN;
652         if (rd_flags & NL80211_RRF_NO_IBSS)
653                 channel_flags |= IEEE80211_CHAN_NO_IBSS;
654         if (rd_flags & NL80211_RRF_DFS)
655                 channel_flags |= IEEE80211_CHAN_RADAR;
656         return channel_flags;
657 }
658
659 static int freq_reg_info_regd(struct wiphy *wiphy,
660                               u32 center_freq,
661                               u32 desired_bw_khz,
662                               const struct ieee80211_reg_rule **reg_rule,
663                               const struct ieee80211_regdomain *custom_regd)
664 {
665         int i;
666         bool band_rule_found = false;
667         const struct ieee80211_regdomain *regd;
668         bool bw_fits = false;
669
670         if (!desired_bw_khz)
671                 desired_bw_khz = MHZ_TO_KHZ(20);
672
673         regd = custom_regd ? custom_regd : cfg80211_regdomain;
674
675         /*
676          * Follow the driver's regulatory domain, if present, unless a country
677          * IE has been processed or a user wants to help complaince further
678          */
679         if (!custom_regd &&
680             last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
681             last_request->initiator != NL80211_REGDOM_SET_BY_USER &&
682             wiphy->regd)
683                 regd = wiphy->regd;
684
685         if (!regd)
686                 return -EINVAL;
687
688         for (i = 0; i < regd->n_reg_rules; i++) {
689                 const struct ieee80211_reg_rule *rr;
690                 const struct ieee80211_freq_range *fr = NULL;
691
692                 rr = &regd->reg_rules[i];
693                 fr = &rr->freq_range;
694
695                 /*
696                  * We only need to know if one frequency rule was
697                  * was in center_freq's band, that's enough, so lets
698                  * not overwrite it once found
699                  */
700                 if (!band_rule_found)
701                         band_rule_found = freq_in_rule_band(fr, center_freq);
702
703                 bw_fits = reg_does_bw_fit(fr,
704                                           center_freq,
705                                           desired_bw_khz);
706
707                 if (band_rule_found && bw_fits) {
708                         *reg_rule = rr;
709                         return 0;
710                 }
711         }
712
713         if (!band_rule_found)
714                 return -ERANGE;
715
716         return -EINVAL;
717 }
718
719 int freq_reg_info(struct wiphy *wiphy,
720                   u32 center_freq,
721                   u32 desired_bw_khz,
722                   const struct ieee80211_reg_rule **reg_rule)
723 {
724         assert_cfg80211_lock();
725         return freq_reg_info_regd(wiphy,
726                                   center_freq,
727                                   desired_bw_khz,
728                                   reg_rule,
729                                   NULL);
730 }
731 EXPORT_SYMBOL(freq_reg_info);
732
733 #ifdef CONFIG_CFG80211_REG_DEBUG
734 static const char *reg_initiator_name(enum nl80211_reg_initiator initiator)
735 {
736         switch (initiator) {
737         case NL80211_REGDOM_SET_BY_CORE:
738                 return "Set by core";
739         case NL80211_REGDOM_SET_BY_USER:
740                 return "Set by user";
741         case NL80211_REGDOM_SET_BY_DRIVER:
742                 return "Set by driver";
743         case NL80211_REGDOM_SET_BY_COUNTRY_IE:
744                 return "Set by country IE";
745         default:
746                 WARN_ON(1);
747                 return "Set by bug";
748         }
749 }
750
751 static void chan_reg_rule_print_dbg(struct ieee80211_channel *chan,
752                                     u32 desired_bw_khz,
753                                     const struct ieee80211_reg_rule *reg_rule)
754 {
755         const struct ieee80211_power_rule *power_rule;
756         const struct ieee80211_freq_range *freq_range;
757         char max_antenna_gain[32];
758
759         power_rule = &reg_rule->power_rule;
760         freq_range = &reg_rule->freq_range;
761
762         if (!power_rule->max_antenna_gain)
763                 snprintf(max_antenna_gain, 32, "N/A");
764         else
765                 snprintf(max_antenna_gain, 32, "%d", power_rule->max_antenna_gain);
766
767         REG_DBG_PRINT("Updating information on frequency %d MHz "
768                       "for a %d MHz width channel with regulatory rule:\n",
769                       chan->center_freq,
770                       KHZ_TO_MHZ(desired_bw_khz));
771
772         REG_DBG_PRINT("%d KHz - %d KHz @  KHz), (%s mBi, %d mBm)\n",
773                       freq_range->start_freq_khz,
774                       freq_range->end_freq_khz,
775                       max_antenna_gain,
776                       power_rule->max_eirp);
777 }
778 #else
779 static void chan_reg_rule_print_dbg(struct ieee80211_channel *chan,
780                                     u32 desired_bw_khz,
781                                     const struct ieee80211_reg_rule *reg_rule)
782 {
783         return;
784 }
785 #endif
786
787 /*
788  * Note that right now we assume the desired channel bandwidth
789  * is always 20 MHz for each individual channel (HT40 uses 20 MHz
790  * per channel, the primary and the extension channel). To support
791  * smaller custom bandwidths such as 5 MHz or 10 MHz we'll need a
792  * new ieee80211_channel.target_bw and re run the regulatory check
793  * on the wiphy with the target_bw specified. Then we can simply use
794  * that below for the desired_bw_khz below.
795  */
796 static void handle_channel(struct wiphy *wiphy,
797                            enum nl80211_reg_initiator initiator,
798                            enum ieee80211_band band,
799                            unsigned int chan_idx)
800 {
801         int r;
802         u32 flags, bw_flags = 0;
803         u32 desired_bw_khz = MHZ_TO_KHZ(20);
804         const struct ieee80211_reg_rule *reg_rule = NULL;
805         const struct ieee80211_power_rule *power_rule = NULL;
806         const struct ieee80211_freq_range *freq_range = NULL;
807         struct ieee80211_supported_band *sband;
808         struct ieee80211_channel *chan;
809         struct wiphy *request_wiphy = NULL;
810
811         assert_cfg80211_lock();
812
813         request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
814
815         sband = wiphy->bands[band];
816         BUG_ON(chan_idx >= sband->n_channels);
817         chan = &sband->channels[chan_idx];
818
819         flags = chan->orig_flags;
820
821         r = freq_reg_info(wiphy,
822                           MHZ_TO_KHZ(chan->center_freq),
823                           desired_bw_khz,
824                           &reg_rule);
825
826         if (r) {
827                 /*
828                  * We will disable all channels that do not match our
829                  * received regulatory rule unless the hint is coming
830                  * from a Country IE and the Country IE had no information
831                  * about a band. The IEEE 802.11 spec allows for an AP
832                  * to send only a subset of the regulatory rules allowed,
833                  * so an AP in the US that only supports 2.4 GHz may only send
834                  * a country IE with information for the 2.4 GHz band
835                  * while 5 GHz is still supported.
836                  */
837                 if (initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE &&
838                     r == -ERANGE)
839                         return;
840
841                 REG_DBG_PRINT("Disabling freq %d MHz\n", chan->center_freq);
842                 chan->flags = IEEE80211_CHAN_DISABLED;
843                 return;
844         }
845
846         chan_reg_rule_print_dbg(chan, desired_bw_khz, reg_rule);
847
848         power_rule = &reg_rule->power_rule;
849         freq_range = &reg_rule->freq_range;
850
851         if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
852                 bw_flags = IEEE80211_CHAN_NO_HT40;
853
854         if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
855             request_wiphy && request_wiphy == wiphy &&
856             request_wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY) {
857                 /*
858                  * This guarantees the driver's requested regulatory domain
859                  * will always be used as a base for further regulatory
860                  * settings
861                  */
862                 chan->flags = chan->orig_flags =
863                         map_regdom_flags(reg_rule->flags) | bw_flags;
864                 chan->max_antenna_gain = chan->orig_mag =
865                         (int) MBI_TO_DBI(power_rule->max_antenna_gain);
866                 chan->max_power = chan->orig_mpwr =
867                         (int) MBM_TO_DBM(power_rule->max_eirp);
868                 return;
869         }
870
871         chan->beacon_found = false;
872         chan->flags = flags | bw_flags | map_regdom_flags(reg_rule->flags);
873         chan->max_antenna_gain = min(chan->orig_mag,
874                 (int) MBI_TO_DBI(power_rule->max_antenna_gain));
875         if (chan->orig_mpwr)
876                 chan->max_power = min(chan->orig_mpwr,
877                         (int) MBM_TO_DBM(power_rule->max_eirp));
878         else
879                 chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
880 }
881
882 static void handle_band(struct wiphy *wiphy,
883                         enum ieee80211_band band,
884                         enum nl80211_reg_initiator initiator)
885 {
886         unsigned int i;
887         struct ieee80211_supported_band *sband;
888
889         BUG_ON(!wiphy->bands[band]);
890         sband = wiphy->bands[band];
891
892         for (i = 0; i < sband->n_channels; i++)
893                 handle_channel(wiphy, initiator, band, i);
894 }
895
896 static bool ignore_reg_update(struct wiphy *wiphy,
897                               enum nl80211_reg_initiator initiator)
898 {
899         if (!last_request) {
900                 REG_DBG_PRINT("Ignoring regulatory request %s since "
901                               "last_request is not set\n",
902                               reg_initiator_name(initiator));
903                 return true;
904         }
905
906         if (initiator == NL80211_REGDOM_SET_BY_CORE &&
907             wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY) {
908                 REG_DBG_PRINT("Ignoring regulatory request %s "
909                               "since the driver uses its own custom "
910                               "regulatory domain ",
911                               reg_initiator_name(initiator));
912                 return true;
913         }
914
915         /*
916          * wiphy->regd will be set once the device has its own
917          * desired regulatory domain set
918          */
919         if (wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY && !wiphy->regd &&
920             initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
921             !is_world_regdom(last_request->alpha2)) {
922                 REG_DBG_PRINT("Ignoring regulatory request %s "
923                               "since the driver requires its own regulatory "
924                               "domain to be set first",
925                               reg_initiator_name(initiator));
926                 return true;
927         }
928
929         return false;
930 }
931
932 static void update_all_wiphy_regulatory(enum nl80211_reg_initiator initiator)
933 {
934         struct cfg80211_registered_device *rdev;
935
936         list_for_each_entry(rdev, &cfg80211_rdev_list, list)
937                 wiphy_update_regulatory(&rdev->wiphy, initiator);
938 }
939
940 static void handle_reg_beacon(struct wiphy *wiphy,
941                               unsigned int chan_idx,
942                               struct reg_beacon *reg_beacon)
943 {
944         struct ieee80211_supported_band *sband;
945         struct ieee80211_channel *chan;
946         bool channel_changed = false;
947         struct ieee80211_channel chan_before;
948
949         assert_cfg80211_lock();
950
951         sband = wiphy->bands[reg_beacon->chan.band];
952         chan = &sband->channels[chan_idx];
953
954         if (likely(chan->center_freq != reg_beacon->chan.center_freq))
955                 return;
956
957         if (chan->beacon_found)
958                 return;
959
960         chan->beacon_found = true;
961
962         if (wiphy->flags & WIPHY_FLAG_DISABLE_BEACON_HINTS)
963                 return;
964
965         chan_before.center_freq = chan->center_freq;
966         chan_before.flags = chan->flags;
967
968         if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN) {
969                 chan->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
970                 channel_changed = true;
971         }
972
973         if (chan->flags & IEEE80211_CHAN_NO_IBSS) {
974                 chan->flags &= ~IEEE80211_CHAN_NO_IBSS;
975                 channel_changed = true;
976         }
977
978         if (channel_changed)
979                 nl80211_send_beacon_hint_event(wiphy, &chan_before, chan);
980 }
981
982 /*
983  * Called when a scan on a wiphy finds a beacon on
984  * new channel
985  */
986 static void wiphy_update_new_beacon(struct wiphy *wiphy,
987                                     struct reg_beacon *reg_beacon)
988 {
989         unsigned int i;
990         struct ieee80211_supported_band *sband;
991
992         assert_cfg80211_lock();
993
994         if (!wiphy->bands[reg_beacon->chan.band])
995                 return;
996
997         sband = wiphy->bands[reg_beacon->chan.band];
998
999         for (i = 0; i < sband->n_channels; i++)
1000                 handle_reg_beacon(wiphy, i, reg_beacon);
1001 }
1002
1003 /*
1004  * Called upon reg changes or a new wiphy is added
1005  */
1006 static void wiphy_update_beacon_reg(struct wiphy *wiphy)
1007 {
1008         unsigned int i;
1009         struct ieee80211_supported_band *sband;
1010         struct reg_beacon *reg_beacon;
1011
1012         assert_cfg80211_lock();
1013
1014         if (list_empty(&reg_beacon_list))
1015                 return;
1016
1017         list_for_each_entry(reg_beacon, &reg_beacon_list, list) {
1018                 if (!wiphy->bands[reg_beacon->chan.band])
1019                         continue;
1020                 sband = wiphy->bands[reg_beacon->chan.band];
1021                 for (i = 0; i < sband->n_channels; i++)
1022                         handle_reg_beacon(wiphy, i, reg_beacon);
1023         }
1024 }
1025
1026 static bool reg_is_world_roaming(struct wiphy *wiphy)
1027 {
1028         if (is_world_regdom(cfg80211_regdomain->alpha2) ||
1029             (wiphy->regd && is_world_regdom(wiphy->regd->alpha2)))
1030                 return true;
1031         if (last_request &&
1032             last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1033             wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY)
1034                 return true;
1035         return false;
1036 }
1037
1038 /* Reap the advantages of previously found beacons */
1039 static void reg_process_beacons(struct wiphy *wiphy)
1040 {
1041         /*
1042          * Means we are just firing up cfg80211, so no beacons would
1043          * have been processed yet.
1044          */
1045         if (!last_request)
1046                 return;
1047         if (!reg_is_world_roaming(wiphy))
1048                 return;
1049         wiphy_update_beacon_reg(wiphy);
1050 }
1051
1052 static bool is_ht40_not_allowed(struct ieee80211_channel *chan)
1053 {
1054         if (!chan)
1055                 return true;
1056         if (chan->flags & IEEE80211_CHAN_DISABLED)
1057                 return true;
1058         /* This would happen when regulatory rules disallow HT40 completely */
1059         if (IEEE80211_CHAN_NO_HT40 == (chan->flags & (IEEE80211_CHAN_NO_HT40)))
1060                 return true;
1061         return false;
1062 }
1063
1064 static void reg_process_ht_flags_channel(struct wiphy *wiphy,
1065                                          enum ieee80211_band band,
1066                                          unsigned int chan_idx)
1067 {
1068         struct ieee80211_supported_band *sband;
1069         struct ieee80211_channel *channel;
1070         struct ieee80211_channel *channel_before = NULL, *channel_after = NULL;
1071         unsigned int i;
1072
1073         assert_cfg80211_lock();
1074
1075         sband = wiphy->bands[band];
1076         BUG_ON(chan_idx >= sband->n_channels);
1077         channel = &sband->channels[chan_idx];
1078
1079         if (is_ht40_not_allowed(channel)) {
1080                 channel->flags |= IEEE80211_CHAN_NO_HT40;
1081                 return;
1082         }
1083
1084         /*
1085          * We need to ensure the extension channels exist to
1086          * be able to use HT40- or HT40+, this finds them (or not)
1087          */
1088         for (i = 0; i < sband->n_channels; i++) {
1089                 struct ieee80211_channel *c = &sband->channels[i];
1090                 if (c->center_freq == (channel->center_freq - 20))
1091                         channel_before = c;
1092                 if (c->center_freq == (channel->center_freq + 20))
1093                         channel_after = c;
1094         }
1095
1096         /*
1097          * Please note that this assumes target bandwidth is 20 MHz,
1098          * if that ever changes we also need to change the below logic
1099          * to include that as well.
1100          */
1101         if (is_ht40_not_allowed(channel_before))
1102                 channel->flags |= IEEE80211_CHAN_NO_HT40MINUS;
1103         else
1104                 channel->flags &= ~IEEE80211_CHAN_NO_HT40MINUS;
1105
1106         if (is_ht40_not_allowed(channel_after))
1107                 channel->flags |= IEEE80211_CHAN_NO_HT40PLUS;
1108         else
1109                 channel->flags &= ~IEEE80211_CHAN_NO_HT40PLUS;
1110 }
1111
1112 static void reg_process_ht_flags_band(struct wiphy *wiphy,
1113                                       enum ieee80211_band band)
1114 {
1115         unsigned int i;
1116         struct ieee80211_supported_band *sband;
1117
1118         BUG_ON(!wiphy->bands[band]);
1119         sband = wiphy->bands[band];
1120
1121         for (i = 0; i < sband->n_channels; i++)
1122                 reg_process_ht_flags_channel(wiphy, band, i);
1123 }
1124
1125 static void reg_process_ht_flags(struct wiphy *wiphy)
1126 {
1127         enum ieee80211_band band;
1128
1129         if (!wiphy)
1130                 return;
1131
1132         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1133                 if (wiphy->bands[band])
1134                         reg_process_ht_flags_band(wiphy, band);
1135         }
1136
1137 }
1138
1139 void wiphy_update_regulatory(struct wiphy *wiphy,
1140                              enum nl80211_reg_initiator initiator)
1141 {
1142         enum ieee80211_band band;
1143
1144         if (ignore_reg_update(wiphy, initiator))
1145                 return;
1146
1147         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1148                 if (wiphy->bands[band])
1149                         handle_band(wiphy, band, initiator);
1150         }
1151
1152         reg_process_beacons(wiphy);
1153         reg_process_ht_flags(wiphy);
1154         if (wiphy->reg_notifier)
1155                 wiphy->reg_notifier(wiphy, last_request);
1156 }
1157
1158 static void handle_channel_custom(struct wiphy *wiphy,
1159                                   enum ieee80211_band band,
1160                                   unsigned int chan_idx,
1161                                   const struct ieee80211_regdomain *regd)
1162 {
1163         int r;
1164         u32 desired_bw_khz = MHZ_TO_KHZ(20);
1165         u32 bw_flags = 0;
1166         const struct ieee80211_reg_rule *reg_rule = NULL;
1167         const struct ieee80211_power_rule *power_rule = NULL;
1168         const struct ieee80211_freq_range *freq_range = NULL;
1169         struct ieee80211_supported_band *sband;
1170         struct ieee80211_channel *chan;
1171
1172         assert_reg_lock();
1173
1174         sband = wiphy->bands[band];
1175         BUG_ON(chan_idx >= sband->n_channels);
1176         chan = &sband->channels[chan_idx];
1177
1178         r = freq_reg_info_regd(wiphy,
1179                                MHZ_TO_KHZ(chan->center_freq),
1180                                desired_bw_khz,
1181                                &reg_rule,
1182                                regd);
1183
1184         if (r) {
1185                 REG_DBG_PRINT("Disabling freq %d MHz as custom "
1186                               "regd has no rule that fits a %d MHz "
1187                               "wide channel\n",
1188                               chan->center_freq,
1189                               KHZ_TO_MHZ(desired_bw_khz));
1190                 chan->flags = IEEE80211_CHAN_DISABLED;
1191                 return;
1192         }
1193
1194         chan_reg_rule_print_dbg(chan, desired_bw_khz, reg_rule);
1195
1196         power_rule = &reg_rule->power_rule;
1197         freq_range = &reg_rule->freq_range;
1198
1199         if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
1200                 bw_flags = IEEE80211_CHAN_NO_HT40;
1201
1202         chan->flags |= map_regdom_flags(reg_rule->flags) | bw_flags;
1203         chan->max_antenna_gain = (int) MBI_TO_DBI(power_rule->max_antenna_gain);
1204         chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
1205 }
1206
1207 static void handle_band_custom(struct wiphy *wiphy, enum ieee80211_band band,
1208                                const struct ieee80211_regdomain *regd)
1209 {
1210         unsigned int i;
1211         struct ieee80211_supported_band *sband;
1212
1213         BUG_ON(!wiphy->bands[band]);
1214         sband = wiphy->bands[band];
1215
1216         for (i = 0; i < sband->n_channels; i++)
1217                 handle_channel_custom(wiphy, band, i, regd);
1218 }
1219
1220 /* Used by drivers prior to wiphy registration */
1221 void wiphy_apply_custom_regulatory(struct wiphy *wiphy,
1222                                    const struct ieee80211_regdomain *regd)
1223 {
1224         enum ieee80211_band band;
1225         unsigned int bands_set = 0;
1226
1227         mutex_lock(&reg_mutex);
1228         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1229                 if (!wiphy->bands[band])
1230                         continue;
1231                 handle_band_custom(wiphy, band, regd);
1232                 bands_set++;
1233         }
1234         mutex_unlock(&reg_mutex);
1235
1236         /*
1237          * no point in calling this if it won't have any effect
1238          * on your device's supportd bands.
1239          */
1240         WARN_ON(!bands_set);
1241 }
1242 EXPORT_SYMBOL(wiphy_apply_custom_regulatory);
1243
1244 /*
1245  * Return value which can be used by ignore_request() to indicate
1246  * it has been determined we should intersect two regulatory domains
1247  */
1248 #define REG_INTERSECT   1
1249
1250 /* This has the logic which determines when a new request
1251  * should be ignored. */
1252 static int ignore_request(struct wiphy *wiphy,
1253                           struct regulatory_request *pending_request)
1254 {
1255         struct wiphy *last_wiphy = NULL;
1256
1257         assert_cfg80211_lock();
1258
1259         /* All initial requests are respected */
1260         if (!last_request)
1261                 return 0;
1262
1263         switch (pending_request->initiator) {
1264         case NL80211_REGDOM_SET_BY_CORE:
1265                 return 0;
1266         case NL80211_REGDOM_SET_BY_COUNTRY_IE:
1267
1268                 last_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
1269
1270                 if (unlikely(!is_an_alpha2(pending_request->alpha2)))
1271                         return -EINVAL;
1272                 if (last_request->initiator ==
1273                     NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1274                         if (last_wiphy != wiphy) {
1275                                 /*
1276                                  * Two cards with two APs claiming different
1277                                  * Country IE alpha2s. We could
1278                                  * intersect them, but that seems unlikely
1279                                  * to be correct. Reject second one for now.
1280                                  */
1281                                 if (regdom_changes(pending_request->alpha2))
1282                                         return -EOPNOTSUPP;
1283                                 return -EALREADY;
1284                         }
1285                         /*
1286                          * Two consecutive Country IE hints on the same wiphy.
1287                          * This should be picked up early by the driver/stack
1288                          */
1289                         if (WARN_ON(regdom_changes(pending_request->alpha2)))
1290                                 return 0;
1291                         return -EALREADY;
1292                 }
1293                 return 0;
1294         case NL80211_REGDOM_SET_BY_DRIVER:
1295                 if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE) {
1296                         if (regdom_changes(pending_request->alpha2))
1297                                 return 0;
1298                         return -EALREADY;
1299                 }
1300
1301                 /*
1302                  * This would happen if you unplug and plug your card
1303                  * back in or if you add a new device for which the previously
1304                  * loaded card also agrees on the regulatory domain.
1305                  */
1306                 if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1307                     !regdom_changes(pending_request->alpha2))
1308                         return -EALREADY;
1309
1310                 return REG_INTERSECT;
1311         case NL80211_REGDOM_SET_BY_USER:
1312                 if (last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE)
1313                         return REG_INTERSECT;
1314                 /*
1315                  * If the user knows better the user should set the regdom
1316                  * to their country before the IE is picked up
1317                  */
1318                 if (last_request->initiator == NL80211_REGDOM_SET_BY_USER &&
1319                           last_request->intersect)
1320                         return -EOPNOTSUPP;
1321                 /*
1322                  * Process user requests only after previous user/driver/core
1323                  * requests have been processed
1324                  */
1325                 if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE ||
1326                     last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER ||
1327                     last_request->initiator == NL80211_REGDOM_SET_BY_USER) {
1328                         if (regdom_changes(last_request->alpha2))
1329                                 return -EAGAIN;
1330                 }
1331
1332                 if (!regdom_changes(pending_request->alpha2))
1333                         return -EALREADY;
1334
1335                 return 0;
1336         }
1337
1338         return -EINVAL;
1339 }
1340
1341 static void reg_set_request_processed(void)
1342 {
1343         bool need_more_processing = false;
1344
1345         last_request->processed = true;
1346
1347         spin_lock(&reg_requests_lock);
1348         if (!list_empty(&reg_requests_list))
1349                 need_more_processing = true;
1350         spin_unlock(&reg_requests_lock);
1351
1352         if (last_request->initiator == NL80211_REGDOM_SET_BY_USER)
1353                 cancel_delayed_work_sync(&reg_timeout);
1354
1355         if (need_more_processing)
1356                 schedule_work(&reg_work);
1357 }
1358
1359 /**
1360  * __regulatory_hint - hint to the wireless core a regulatory domain
1361  * @wiphy: if the hint comes from country information from an AP, this
1362  *      is required to be set to the wiphy that received the information
1363  * @pending_request: the regulatory request currently being processed
1364  *
1365  * The Wireless subsystem can use this function to hint to the wireless core
1366  * what it believes should be the current regulatory domain.
1367  *
1368  * Returns zero if all went fine, %-EALREADY if a regulatory domain had
1369  * already been set or other standard error codes.
1370  *
1371  * Caller must hold &cfg80211_mutex and &reg_mutex
1372  */
1373 static int __regulatory_hint(struct wiphy *wiphy,
1374                              struct regulatory_request *pending_request)
1375 {
1376         bool intersect = false;
1377         int r = 0;
1378
1379         assert_cfg80211_lock();
1380
1381         r = ignore_request(wiphy, pending_request);
1382
1383         if (r == REG_INTERSECT) {
1384                 if (pending_request->initiator ==
1385                     NL80211_REGDOM_SET_BY_DRIVER) {
1386                         r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1387                         if (r) {
1388                                 kfree(pending_request);
1389                                 return r;
1390                         }
1391                 }
1392                 intersect = true;
1393         } else if (r) {
1394                 /*
1395                  * If the regulatory domain being requested by the
1396                  * driver has already been set just copy it to the
1397                  * wiphy
1398                  */
1399                 if (r == -EALREADY &&
1400                     pending_request->initiator ==
1401                     NL80211_REGDOM_SET_BY_DRIVER) {
1402                         r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1403                         if (r) {
1404                                 kfree(pending_request);
1405                                 return r;
1406                         }
1407                         r = -EALREADY;
1408                         goto new_request;
1409                 }
1410                 kfree(pending_request);
1411                 return r;
1412         }
1413
1414 new_request:
1415         if (last_request != &core_request_world)
1416                 kfree(last_request);
1417
1418         last_request = pending_request;
1419         last_request->intersect = intersect;
1420
1421         pending_request = NULL;
1422
1423         if (last_request->initiator == NL80211_REGDOM_SET_BY_USER) {
1424                 user_alpha2[0] = last_request->alpha2[0];
1425                 user_alpha2[1] = last_request->alpha2[1];
1426         }
1427
1428         /* When r == REG_INTERSECT we do need to call CRDA */
1429         if (r < 0) {
1430                 /*
1431                  * Since CRDA will not be called in this case as we already
1432                  * have applied the requested regulatory domain before we just
1433                  * inform userspace we have processed the request
1434                  */
1435                 if (r == -EALREADY) {
1436                         nl80211_send_reg_change_event(last_request);
1437                         reg_set_request_processed();
1438                 }
1439                 return r;
1440         }
1441
1442         return call_crda(last_request->alpha2);
1443 }
1444
1445 /* This processes *all* regulatory hints */
1446 static void reg_process_hint(struct regulatory_request *reg_request)
1447 {
1448         int r = 0;
1449         struct wiphy *wiphy = NULL;
1450         enum nl80211_reg_initiator initiator = reg_request->initiator;
1451
1452         BUG_ON(!reg_request->alpha2);
1453
1454         if (wiphy_idx_valid(reg_request->wiphy_idx))
1455                 wiphy = wiphy_idx_to_wiphy(reg_request->wiphy_idx);
1456
1457         if (reg_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1458             !wiphy) {
1459                 kfree(reg_request);
1460                 return;
1461         }
1462
1463         r = __regulatory_hint(wiphy, reg_request);
1464         /* This is required so that the orig_* parameters are saved */
1465         if (r == -EALREADY && wiphy &&
1466             wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY) {
1467                 wiphy_update_regulatory(wiphy, initiator);
1468                 return;
1469         }
1470
1471         /*
1472          * We only time out user hints, given that they should be the only
1473          * source of bogus requests.
1474          */
1475         if (r != -EALREADY &&
1476             reg_request->initiator == NL80211_REGDOM_SET_BY_USER)
1477                 schedule_delayed_work(&reg_timeout, msecs_to_jiffies(3142));
1478 }
1479
1480 /*
1481  * Processes regulatory hints, this is all the NL80211_REGDOM_SET_BY_*
1482  * Regulatory hints come on a first come first serve basis and we
1483  * must process each one atomically.
1484  */
1485 static void reg_process_pending_hints(void)
1486 {
1487         struct regulatory_request *reg_request;
1488
1489         mutex_lock(&cfg80211_mutex);
1490         mutex_lock(&reg_mutex);
1491
1492         /* When last_request->processed becomes true this will be rescheduled */
1493         if (last_request && !last_request->processed) {
1494                 REG_DBG_PRINT("Pending regulatory request, waiting "
1495                               "for it to be processed...");
1496                 goto out;
1497         }
1498
1499         spin_lock(&reg_requests_lock);
1500
1501         if (list_empty(&reg_requests_list)) {
1502                 spin_unlock(&reg_requests_lock);
1503                 goto out;
1504         }
1505
1506         reg_request = list_first_entry(&reg_requests_list,
1507                                        struct regulatory_request,
1508                                        list);
1509         list_del_init(&reg_request->list);
1510
1511         spin_unlock(&reg_requests_lock);
1512
1513         reg_process_hint(reg_request);
1514
1515 out:
1516         mutex_unlock(&reg_mutex);
1517         mutex_unlock(&cfg80211_mutex);
1518 }
1519
1520 /* Processes beacon hints -- this has nothing to do with country IEs */
1521 static void reg_process_pending_beacon_hints(void)
1522 {
1523         struct cfg80211_registered_device *rdev;
1524         struct reg_beacon *pending_beacon, *tmp;
1525
1526         /*
1527          * No need to hold the reg_mutex here as we just touch wiphys
1528          * and do not read or access regulatory variables.
1529          */
1530         mutex_lock(&cfg80211_mutex);
1531
1532         /* This goes through the _pending_ beacon list */
1533         spin_lock_bh(&reg_pending_beacons_lock);
1534
1535         if (list_empty(&reg_pending_beacons)) {
1536                 spin_unlock_bh(&reg_pending_beacons_lock);
1537                 goto out;
1538         }
1539
1540         list_for_each_entry_safe(pending_beacon, tmp,
1541                                  &reg_pending_beacons, list) {
1542
1543                 list_del_init(&pending_beacon->list);
1544
1545                 /* Applies the beacon hint to current wiphys */
1546                 list_for_each_entry(rdev, &cfg80211_rdev_list, list)
1547                         wiphy_update_new_beacon(&rdev->wiphy, pending_beacon);
1548
1549                 /* Remembers the beacon hint for new wiphys or reg changes */
1550                 list_add_tail(&pending_beacon->list, &reg_beacon_list);
1551         }
1552
1553         spin_unlock_bh(&reg_pending_beacons_lock);
1554 out:
1555         mutex_unlock(&cfg80211_mutex);
1556 }
1557
1558 static void reg_todo(struct work_struct *work)
1559 {
1560         reg_process_pending_hints();
1561         reg_process_pending_beacon_hints();
1562 }
1563
1564 static void queue_regulatory_request(struct regulatory_request *request)
1565 {
1566         if (isalpha(request->alpha2[0]))
1567                 request->alpha2[0] = toupper(request->alpha2[0]);
1568         if (isalpha(request->alpha2[1]))
1569                 request->alpha2[1] = toupper(request->alpha2[1]);
1570
1571         spin_lock(&reg_requests_lock);
1572         list_add_tail(&request->list, &reg_requests_list);
1573         spin_unlock(&reg_requests_lock);
1574
1575         schedule_work(&reg_work);
1576 }
1577
1578 /*
1579  * Core regulatory hint -- happens during cfg80211_init()
1580  * and when we restore regulatory settings.
1581  */
1582 static int regulatory_hint_core(const char *alpha2)
1583 {
1584         struct regulatory_request *request;
1585
1586         request = kzalloc(sizeof(struct regulatory_request),
1587                           GFP_KERNEL);
1588         if (!request)
1589                 return -ENOMEM;
1590
1591         request->alpha2[0] = alpha2[0];
1592         request->alpha2[1] = alpha2[1];
1593         request->initiator = NL80211_REGDOM_SET_BY_CORE;
1594
1595         queue_regulatory_request(request);
1596
1597         return 0;
1598 }
1599
1600 /* User hints */
1601 int regulatory_hint_user(const char *alpha2)
1602 {
1603         struct regulatory_request *request;
1604
1605         BUG_ON(!alpha2);
1606
1607         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1608         if (!request)
1609                 return -ENOMEM;
1610
1611         request->wiphy_idx = WIPHY_IDX_STALE;
1612         request->alpha2[0] = alpha2[0];
1613         request->alpha2[1] = alpha2[1];
1614         request->initiator = NL80211_REGDOM_SET_BY_USER;
1615
1616         queue_regulatory_request(request);
1617
1618         return 0;
1619 }
1620
1621 /* Driver hints */
1622 int regulatory_hint(struct wiphy *wiphy, const char *alpha2)
1623 {
1624         struct regulatory_request *request;
1625
1626         BUG_ON(!alpha2);
1627         BUG_ON(!wiphy);
1628
1629         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1630         if (!request)
1631                 return -ENOMEM;
1632
1633         request->wiphy_idx = get_wiphy_idx(wiphy);
1634
1635         /* Must have registered wiphy first */
1636         BUG_ON(!wiphy_idx_valid(request->wiphy_idx));
1637
1638         request->alpha2[0] = alpha2[0];
1639         request->alpha2[1] = alpha2[1];
1640         request->initiator = NL80211_REGDOM_SET_BY_DRIVER;
1641
1642         queue_regulatory_request(request);
1643
1644         return 0;
1645 }
1646 EXPORT_SYMBOL(regulatory_hint);
1647
1648 /*
1649  * We hold wdev_lock() here so we cannot hold cfg80211_mutex() and
1650  * therefore cannot iterate over the rdev list here.
1651  */
1652 void regulatory_hint_11d(struct wiphy *wiphy,
1653                          enum ieee80211_band band,
1654                          u8 *country_ie,
1655                          u8 country_ie_len)
1656 {
1657         char alpha2[2];
1658         enum environment_cap env = ENVIRON_ANY;
1659         struct regulatory_request *request;
1660
1661         mutex_lock(&reg_mutex);
1662
1663         if (unlikely(!last_request))
1664                 goto out;
1665
1666         /* IE len must be evenly divisible by 2 */
1667         if (country_ie_len & 0x01)
1668                 goto out;
1669
1670         if (country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN)
1671                 goto out;
1672
1673         alpha2[0] = country_ie[0];
1674         alpha2[1] = country_ie[1];
1675
1676         if (country_ie[2] == 'I')
1677                 env = ENVIRON_INDOOR;
1678         else if (country_ie[2] == 'O')
1679                 env = ENVIRON_OUTDOOR;
1680
1681         /*
1682          * We will run this only upon a successful connection on cfg80211.
1683          * We leave conflict resolution to the workqueue, where can hold
1684          * cfg80211_mutex.
1685          */
1686         if (likely(last_request->initiator ==
1687             NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1688             wiphy_idx_valid(last_request->wiphy_idx)))
1689                 goto out;
1690
1691         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1692         if (!request)
1693                 goto out;
1694
1695         request->wiphy_idx = get_wiphy_idx(wiphy);
1696         request->alpha2[0] = alpha2[0];
1697         request->alpha2[1] = alpha2[1];
1698         request->initiator = NL80211_REGDOM_SET_BY_COUNTRY_IE;
1699         request->country_ie_env = env;
1700
1701         mutex_unlock(&reg_mutex);
1702
1703         queue_regulatory_request(request);
1704
1705         return;
1706
1707 out:
1708         mutex_unlock(&reg_mutex);
1709 }
1710
1711 static void restore_alpha2(char *alpha2, bool reset_user)
1712 {
1713         /* indicates there is no alpha2 to consider for restoration */
1714         alpha2[0] = '9';
1715         alpha2[1] = '7';
1716
1717         /* The user setting has precedence over the module parameter */
1718         if (is_user_regdom_saved()) {
1719                 /* Unless we're asked to ignore it and reset it */
1720                 if (reset_user) {
1721                         REG_DBG_PRINT("Restoring regulatory settings "
1722                                "including user preference\n");
1723                         user_alpha2[0] = '9';
1724                         user_alpha2[1] = '7';
1725
1726                         /*
1727                          * If we're ignoring user settings, we still need to
1728                          * check the module parameter to ensure we put things
1729                          * back as they were for a full restore.
1730                          */
1731                         if (!is_world_regdom(ieee80211_regdom)) {
1732                                 REG_DBG_PRINT("Keeping preference on "
1733                                        "module parameter ieee80211_regdom: %c%c\n",
1734                                        ieee80211_regdom[0],
1735                                        ieee80211_regdom[1]);
1736                                 alpha2[0] = ieee80211_regdom[0];
1737                                 alpha2[1] = ieee80211_regdom[1];
1738                         }
1739                 } else {
1740                         REG_DBG_PRINT("Restoring regulatory settings "
1741                                "while preserving user preference for: %c%c\n",
1742                                user_alpha2[0],
1743                                user_alpha2[1]);
1744                         alpha2[0] = user_alpha2[0];
1745                         alpha2[1] = user_alpha2[1];
1746                 }
1747         } else if (!is_world_regdom(ieee80211_regdom)) {
1748                 REG_DBG_PRINT("Keeping preference on "
1749                        "module parameter ieee80211_regdom: %c%c\n",
1750                        ieee80211_regdom[0],
1751                        ieee80211_regdom[1]);
1752                 alpha2[0] = ieee80211_regdom[0];
1753                 alpha2[1] = ieee80211_regdom[1];
1754         } else
1755                 REG_DBG_PRINT("Restoring regulatory settings\n");
1756 }
1757
1758 /*
1759  * Restoring regulatory settings involves ingoring any
1760  * possibly stale country IE information and user regulatory
1761  * settings if so desired, this includes any beacon hints
1762  * learned as we could have traveled outside to another country
1763  * after disconnection. To restore regulatory settings we do
1764  * exactly what we did at bootup:
1765  *
1766  *   - send a core regulatory hint
1767  *   - send a user regulatory hint if applicable
1768  *
1769  * Device drivers that send a regulatory hint for a specific country
1770  * keep their own regulatory domain on wiphy->regd so that does does
1771  * not need to be remembered.
1772  */
1773 static void restore_regulatory_settings(bool reset_user)
1774 {
1775         char alpha2[2];
1776         struct reg_beacon *reg_beacon, *btmp;
1777         struct regulatory_request *reg_request, *tmp;
1778         LIST_HEAD(tmp_reg_req_list);
1779
1780         mutex_lock(&cfg80211_mutex);
1781         mutex_lock(&reg_mutex);
1782
1783         reset_regdomains(true);
1784         restore_alpha2(alpha2, reset_user);
1785
1786         /*
1787          * If there's any pending requests we simply
1788          * stash them to a temporary pending queue and
1789          * add then after we've restored regulatory
1790          * settings.
1791          */
1792         spin_lock(&reg_requests_lock);
1793         if (!list_empty(&reg_requests_list)) {
1794                 list_for_each_entry_safe(reg_request, tmp,
1795                                          &reg_requests_list, list) {
1796                         if (reg_request->initiator !=
1797                             NL80211_REGDOM_SET_BY_USER)
1798                                 continue;
1799                         list_del(&reg_request->list);
1800                         list_add_tail(&reg_request->list, &tmp_reg_req_list);
1801                 }
1802         }
1803         spin_unlock(&reg_requests_lock);
1804
1805         /* Clear beacon hints */
1806         spin_lock_bh(&reg_pending_beacons_lock);
1807         if (!list_empty(&reg_pending_beacons)) {
1808                 list_for_each_entry_safe(reg_beacon, btmp,
1809                                          &reg_pending_beacons, list) {
1810                         list_del(&reg_beacon->list);
1811                         kfree(reg_beacon);
1812                 }
1813         }
1814         spin_unlock_bh(&reg_pending_beacons_lock);
1815
1816         if (!list_empty(&reg_beacon_list)) {
1817                 list_for_each_entry_safe(reg_beacon, btmp,
1818                                          &reg_beacon_list, list) {
1819                         list_del(&reg_beacon->list);
1820                         kfree(reg_beacon);
1821                 }
1822         }
1823
1824         /* First restore to the basic regulatory settings */
1825         cfg80211_regdomain = cfg80211_world_regdom;
1826
1827         mutex_unlock(&reg_mutex);
1828         mutex_unlock(&cfg80211_mutex);
1829
1830         regulatory_hint_core(cfg80211_regdomain->alpha2);
1831
1832         /*
1833          * This restores the ieee80211_regdom module parameter
1834          * preference or the last user requested regulatory
1835          * settings, user regulatory settings takes precedence.
1836          */
1837         if (is_an_alpha2(alpha2))
1838                 regulatory_hint_user(user_alpha2);
1839
1840         if (list_empty(&tmp_reg_req_list))
1841                 return;
1842
1843         mutex_lock(&cfg80211_mutex);
1844         mutex_lock(&reg_mutex);
1845
1846         spin_lock(&reg_requests_lock);
1847         list_for_each_entry_safe(reg_request, tmp, &tmp_reg_req_list, list) {
1848                 REG_DBG_PRINT("Adding request for country %c%c back "
1849                               "into the queue\n",
1850                               reg_request->alpha2[0],
1851                               reg_request->alpha2[1]);
1852                 list_del(&reg_request->list);
1853                 list_add_tail(&reg_request->list, &reg_requests_list);
1854         }
1855         spin_unlock(&reg_requests_lock);
1856
1857         mutex_unlock(&reg_mutex);
1858         mutex_unlock(&cfg80211_mutex);
1859
1860         REG_DBG_PRINT("Kicking the queue\n");
1861
1862         schedule_work(&reg_work);
1863 }
1864
1865 void regulatory_hint_disconnect(void)
1866 {
1867         REG_DBG_PRINT("All devices are disconnected, going to "
1868                       "restore regulatory settings\n");
1869         restore_regulatory_settings(false);
1870 }
1871
1872 static bool freq_is_chan_12_13_14(u16 freq)
1873 {
1874         if (freq == ieee80211_channel_to_frequency(12, IEEE80211_BAND_2GHZ) ||
1875             freq == ieee80211_channel_to_frequency(13, IEEE80211_BAND_2GHZ) ||
1876             freq == ieee80211_channel_to_frequency(14, IEEE80211_BAND_2GHZ))
1877                 return true;
1878         return false;
1879 }
1880
1881 int regulatory_hint_found_beacon(struct wiphy *wiphy,
1882                                  struct ieee80211_channel *beacon_chan,
1883                                  gfp_t gfp)
1884 {
1885         struct reg_beacon *reg_beacon;
1886
1887         if (likely((beacon_chan->beacon_found ||
1888             (beacon_chan->flags & IEEE80211_CHAN_RADAR) ||
1889             (beacon_chan->band == IEEE80211_BAND_2GHZ &&
1890              !freq_is_chan_12_13_14(beacon_chan->center_freq)))))
1891                 return 0;
1892
1893         reg_beacon = kzalloc(sizeof(struct reg_beacon), gfp);
1894         if (!reg_beacon)
1895                 return -ENOMEM;
1896
1897         REG_DBG_PRINT("Found new beacon on "
1898                       "frequency: %d MHz (Ch %d) on %s\n",
1899                       beacon_chan->center_freq,
1900                       ieee80211_frequency_to_channel(beacon_chan->center_freq),
1901                       wiphy_name(wiphy));
1902
1903         memcpy(&reg_beacon->chan, beacon_chan,
1904                 sizeof(struct ieee80211_channel));
1905
1906
1907         /*
1908          * Since we can be called from BH or and non-BH context
1909          * we must use spin_lock_bh()
1910          */
1911         spin_lock_bh(&reg_pending_beacons_lock);
1912         list_add_tail(&reg_beacon->list, &reg_pending_beacons);
1913         spin_unlock_bh(&reg_pending_beacons_lock);
1914
1915         schedule_work(&reg_work);
1916
1917         return 0;
1918 }
1919
1920 static void print_rd_rules(const struct ieee80211_regdomain *rd)
1921 {
1922         unsigned int i;
1923         const struct ieee80211_reg_rule *reg_rule = NULL;
1924         const struct ieee80211_freq_range *freq_range = NULL;
1925         const struct ieee80211_power_rule *power_rule = NULL;
1926
1927         pr_info("    (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)\n");
1928
1929         for (i = 0; i < rd->n_reg_rules; i++) {
1930                 reg_rule = &rd->reg_rules[i];
1931                 freq_range = &reg_rule->freq_range;
1932                 power_rule = &reg_rule->power_rule;
1933
1934                 /*
1935                  * There may not be documentation for max antenna gain
1936                  * in certain regions
1937                  */
1938                 if (power_rule->max_antenna_gain)
1939                         pr_info("    (%d KHz - %d KHz @ %d KHz), (%d mBi, %d mBm)\n",
1940                                 freq_range->start_freq_khz,
1941                                 freq_range->end_freq_khz,
1942                                 freq_range->max_bandwidth_khz,
1943                                 power_rule->max_antenna_gain,
1944                                 power_rule->max_eirp);
1945                 else
1946                         pr_info("    (%d KHz - %d KHz @ %d KHz), (N/A, %d mBm)\n",
1947                                 freq_range->start_freq_khz,
1948                                 freq_range->end_freq_khz,
1949                                 freq_range->max_bandwidth_khz,
1950                                 power_rule->max_eirp);
1951         }
1952 }
1953
1954 static void print_regdomain(const struct ieee80211_regdomain *rd)
1955 {
1956
1957         if (is_intersected_alpha2(rd->alpha2)) {
1958
1959                 if (last_request->initiator ==
1960                     NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1961                         struct cfg80211_registered_device *rdev;
1962                         rdev = cfg80211_rdev_by_wiphy_idx(
1963                                 last_request->wiphy_idx);
1964                         if (rdev) {
1965                                 pr_info("Current regulatory domain updated by AP to: %c%c\n",
1966                                         rdev->country_ie_alpha2[0],
1967                                         rdev->country_ie_alpha2[1]);
1968                         } else
1969                                 pr_info("Current regulatory domain intersected:\n");
1970                 } else
1971                         pr_info("Current regulatory domain intersected:\n");
1972         } else if (is_world_regdom(rd->alpha2))
1973                 pr_info("World regulatory domain updated:\n");
1974         else {
1975                 if (is_unknown_alpha2(rd->alpha2))
1976                         pr_info("Regulatory domain changed to driver built-in settings (unknown country)\n");
1977                 else
1978                         pr_info("Regulatory domain changed to country: %c%c\n",
1979                                 rd->alpha2[0], rd->alpha2[1]);
1980         }
1981         print_rd_rules(rd);
1982 }
1983
1984 static void print_regdomain_info(const struct ieee80211_regdomain *rd)
1985 {
1986         pr_info("Regulatory domain: %c%c\n", rd->alpha2[0], rd->alpha2[1]);
1987         print_rd_rules(rd);
1988 }
1989
1990 /* Takes ownership of rd only if it doesn't fail */
1991 static int __set_regdom(const struct ieee80211_regdomain *rd)
1992 {
1993         const struct ieee80211_regdomain *intersected_rd = NULL;
1994         struct cfg80211_registered_device *rdev = NULL;
1995         struct wiphy *request_wiphy;
1996         /* Some basic sanity checks first */
1997
1998         if (is_world_regdom(rd->alpha2)) {
1999                 if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
2000                         return -EINVAL;
2001                 update_world_regdomain(rd);
2002                 return 0;
2003         }
2004
2005         if (!is_alpha2_set(rd->alpha2) && !is_an_alpha2(rd->alpha2) &&
2006                         !is_unknown_alpha2(rd->alpha2))
2007                 return -EINVAL;
2008
2009         if (!last_request)
2010                 return -EINVAL;
2011
2012         /*
2013          * Lets only bother proceeding on the same alpha2 if the current
2014          * rd is non static (it means CRDA was present and was used last)
2015          * and the pending request came in from a country IE
2016          */
2017         if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2018                 /*
2019                  * If someone else asked us to change the rd lets only bother
2020                  * checking if the alpha2 changes if CRDA was already called
2021                  */
2022                 if (!regdom_changes(rd->alpha2))
2023                         return -EINVAL;
2024         }
2025
2026         /*
2027          * Now lets set the regulatory domain, update all driver channels
2028          * and finally inform them of what we have done, in case they want
2029          * to review or adjust their own settings based on their own
2030          * internal EEPROM data
2031          */
2032
2033         if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
2034                 return -EINVAL;
2035
2036         if (!is_valid_rd(rd)) {
2037                 pr_err("Invalid regulatory domain detected:\n");
2038                 print_regdomain_info(rd);
2039                 return -EINVAL;
2040         }
2041
2042         request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
2043         if (!request_wiphy &&
2044             (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER ||
2045              last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE)) {
2046                 schedule_delayed_work(&reg_timeout, 0);
2047                 return -ENODEV;
2048         }
2049
2050         if (!last_request->intersect) {
2051                 int r;
2052
2053                 if (last_request->initiator != NL80211_REGDOM_SET_BY_DRIVER) {
2054                         reset_regdomains(false);
2055                         cfg80211_regdomain = rd;
2056                         return 0;
2057                 }
2058
2059                 /*
2060                  * For a driver hint, lets copy the regulatory domain the
2061                  * driver wanted to the wiphy to deal with conflicts
2062                  */
2063
2064                 /*
2065                  * Userspace could have sent two replies with only
2066                  * one kernel request.
2067                  */
2068                 if (request_wiphy->regd)
2069                         return -EALREADY;
2070
2071                 r = reg_copy_regd(&request_wiphy->regd, rd);
2072                 if (r)
2073                         return r;
2074
2075                 reset_regdomains(false);
2076                 cfg80211_regdomain = rd;
2077                 return 0;
2078         }
2079
2080         /* Intersection requires a bit more work */
2081
2082         if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2083
2084                 intersected_rd = regdom_intersect(rd, cfg80211_regdomain);
2085                 if (!intersected_rd)
2086                         return -EINVAL;
2087
2088                 /*
2089                  * We can trash what CRDA provided now.
2090                  * However if a driver requested this specific regulatory
2091                  * domain we keep it for its private use
2092                  */
2093                 if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER)
2094                         request_wiphy->regd = rd;
2095                 else
2096                         kfree(rd);
2097
2098                 rd = NULL;
2099
2100                 reset_regdomains(false);
2101                 cfg80211_regdomain = intersected_rd;
2102
2103                 return 0;
2104         }
2105
2106         if (!intersected_rd)
2107                 return -EINVAL;
2108
2109         rdev = wiphy_to_dev(request_wiphy);
2110
2111         rdev->country_ie_alpha2[0] = rd->alpha2[0];
2112         rdev->country_ie_alpha2[1] = rd->alpha2[1];
2113         rdev->env = last_request->country_ie_env;
2114
2115         BUG_ON(intersected_rd == rd);
2116
2117         kfree(rd);
2118         rd = NULL;
2119
2120         reset_regdomains(false);
2121         cfg80211_regdomain = intersected_rd;
2122
2123         return 0;
2124 }
2125
2126
2127 /*
2128  * Use this call to set the current regulatory domain. Conflicts with
2129  * multiple drivers can be ironed out later. Caller must've already
2130  * kmalloc'd the rd structure. Caller must hold cfg80211_mutex
2131  */
2132 int set_regdom(const struct ieee80211_regdomain *rd)
2133 {
2134         int r;
2135
2136         assert_cfg80211_lock();
2137
2138         mutex_lock(&reg_mutex);
2139
2140         /* Note that this doesn't update the wiphys, this is done below */
2141         r = __set_regdom(rd);
2142         if (r) {
2143                 kfree(rd);
2144                 mutex_unlock(&reg_mutex);
2145                 return r;
2146         }
2147
2148         /* This would make this whole thing pointless */
2149         if (!last_request->intersect)
2150                 BUG_ON(rd != cfg80211_regdomain);
2151
2152         /* update all wiphys now with the new established regulatory domain */
2153         update_all_wiphy_regulatory(last_request->initiator);
2154
2155         print_regdomain(cfg80211_regdomain);
2156
2157         nl80211_send_reg_change_event(last_request);
2158
2159         reg_set_request_processed();
2160
2161         mutex_unlock(&reg_mutex);
2162
2163         return r;
2164 }
2165
2166 #ifdef CONFIG_HOTPLUG
2167 int reg_device_uevent(struct device *dev, struct kobj_uevent_env *env)
2168 {
2169         if (last_request && !last_request->processed) {
2170                 if (add_uevent_var(env, "COUNTRY=%c%c",
2171                                    last_request->alpha2[0],
2172                                    last_request->alpha2[1]))
2173                         return -ENOMEM;
2174         }
2175
2176         return 0;
2177 }
2178 #else
2179 int reg_device_uevent(struct device *dev, struct kobj_uevent_env *env)
2180 {
2181         return -ENODEV;
2182 }
2183 #endif /* CONFIG_HOTPLUG */
2184
2185 /* Caller must hold cfg80211_mutex */
2186 void reg_device_remove(struct wiphy *wiphy)
2187 {
2188         struct wiphy *request_wiphy = NULL;
2189
2190         assert_cfg80211_lock();
2191
2192         mutex_lock(&reg_mutex);
2193
2194         kfree(wiphy->regd);
2195
2196         if (last_request)
2197                 request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
2198
2199         if (!request_wiphy || request_wiphy != wiphy)
2200                 goto out;
2201
2202         last_request->wiphy_idx = WIPHY_IDX_STALE;
2203         last_request->country_ie_env = ENVIRON_ANY;
2204 out:
2205         mutex_unlock(&reg_mutex);
2206 }
2207
2208 static void reg_timeout_work(struct work_struct *work)
2209 {
2210         REG_DBG_PRINT("Timeout while waiting for CRDA to reply, "
2211                       "restoring regulatory settings");
2212         restore_regulatory_settings(true);
2213 }
2214
2215 int __init regulatory_init(void)
2216 {
2217         int err = 0;
2218
2219         reg_pdev = platform_device_register_simple("regulatory", 0, NULL, 0);
2220         if (IS_ERR(reg_pdev))
2221                 return PTR_ERR(reg_pdev);
2222
2223         reg_pdev->dev.type = &reg_device_type;
2224
2225         spin_lock_init(&reg_requests_lock);
2226         spin_lock_init(&reg_pending_beacons_lock);
2227
2228         cfg80211_regdomain = cfg80211_world_regdom;
2229
2230         user_alpha2[0] = '9';
2231         user_alpha2[1] = '7';
2232
2233         /* We always try to get an update for the static regdomain */
2234         err = regulatory_hint_core(cfg80211_regdomain->alpha2);
2235         if (err) {
2236                 if (err == -ENOMEM)
2237                         return err;
2238                 /*
2239                  * N.B. kobject_uevent_env() can fail mainly for when we're out
2240                  * memory which is handled and propagated appropriately above
2241                  * but it can also fail during a netlink_broadcast() or during
2242                  * early boot for call_usermodehelper(). For now treat these
2243                  * errors as non-fatal.
2244                  */
2245                 pr_err("kobject_uevent_env() was unable to call CRDA during init\n");
2246 #ifdef CONFIG_CFG80211_REG_DEBUG
2247                 /* We want to find out exactly why when debugging */
2248                 WARN_ON(err);
2249 #endif
2250         }
2251
2252         /*
2253          * Finally, if the user set the module parameter treat it
2254          * as a user hint.
2255          */
2256         if (!is_world_regdom(ieee80211_regdom))
2257                 regulatory_hint_user(ieee80211_regdom);
2258
2259         return 0;
2260 }
2261
2262 void /* __init_or_exit */ regulatory_exit(void)
2263 {
2264         struct regulatory_request *reg_request, *tmp;
2265         struct reg_beacon *reg_beacon, *btmp;
2266
2267         cancel_work_sync(&reg_work);
2268         cancel_delayed_work_sync(&reg_timeout);
2269
2270         mutex_lock(&cfg80211_mutex);
2271         mutex_lock(&reg_mutex);
2272
2273         reset_regdomains(true);
2274
2275         dev_set_uevent_suppress(&reg_pdev->dev, true);
2276
2277         platform_device_unregister(reg_pdev);
2278
2279         spin_lock_bh(&reg_pending_beacons_lock);
2280         if (!list_empty(&reg_pending_beacons)) {
2281                 list_for_each_entry_safe(reg_beacon, btmp,
2282                                          &reg_pending_beacons, list) {
2283                         list_del(&reg_beacon->list);
2284                         kfree(reg_beacon);
2285                 }
2286         }
2287         spin_unlock_bh(&reg_pending_beacons_lock);
2288
2289         if (!list_empty(&reg_beacon_list)) {
2290                 list_for_each_entry_safe(reg_beacon, btmp,
2291                                          &reg_beacon_list, list) {
2292                         list_del(&reg_beacon->list);
2293                         kfree(reg_beacon);
2294                 }
2295         }
2296
2297         spin_lock(&reg_requests_lock);
2298         if (!list_empty(&reg_requests_list)) {
2299                 list_for_each_entry_safe(reg_request, tmp,
2300                                          &reg_requests_list, list) {
2301                         list_del(&reg_request->list);
2302                         kfree(reg_request);
2303                 }
2304         }
2305         spin_unlock(&reg_requests_lock);
2306
2307         mutex_unlock(&reg_mutex);
2308         mutex_unlock(&cfg80211_mutex);
2309 }