xref: /linux/net/wireless/reg.c (revision eecb20720f1b29019725515051e41bc7c079f91f)
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 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 @ %d KHz), (%s mBi, %d mBm)\n",
773 		      freq_range->start_freq_khz,
774 		      freq_range->end_freq_khz,
775 		      freq_range->max_bandwidth_khz,
776 		      max_antenna_gain,
777 		      power_rule->max_eirp);
778 }
779 #else
780 static void chan_reg_rule_print_dbg(struct ieee80211_channel *chan,
781 				    u32 desired_bw_khz,
782 				    const struct ieee80211_reg_rule *reg_rule)
783 {
784 	return;
785 }
786 #endif
787 
788 /*
789  * Note that right now we assume the desired channel bandwidth
790  * is always 20 MHz for each individual channel (HT40 uses 20 MHz
791  * per channel, the primary and the extension channel). To support
792  * smaller custom bandwidths such as 5 MHz or 10 MHz we'll need a
793  * new ieee80211_channel.target_bw and re run the regulatory check
794  * on the wiphy with the target_bw specified. Then we can simply use
795  * that below for the desired_bw_khz below.
796  */
797 static void handle_channel(struct wiphy *wiphy,
798 			   enum nl80211_reg_initiator initiator,
799 			   enum ieee80211_band band,
800 			   unsigned int chan_idx)
801 {
802 	int r;
803 	u32 flags, bw_flags = 0;
804 	u32 desired_bw_khz = MHZ_TO_KHZ(20);
805 	const struct ieee80211_reg_rule *reg_rule = NULL;
806 	const struct ieee80211_power_rule *power_rule = NULL;
807 	const struct ieee80211_freq_range *freq_range = NULL;
808 	struct ieee80211_supported_band *sband;
809 	struct ieee80211_channel *chan;
810 	struct wiphy *request_wiphy = NULL;
811 
812 	assert_cfg80211_lock();
813 
814 	request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
815 
816 	sband = wiphy->bands[band];
817 	BUG_ON(chan_idx >= sband->n_channels);
818 	chan = &sband->channels[chan_idx];
819 
820 	flags = chan->orig_flags;
821 
822 	r = freq_reg_info(wiphy,
823 			  MHZ_TO_KHZ(chan->center_freq),
824 			  desired_bw_khz,
825 			  &reg_rule);
826 
827 	if (r) {
828 		/*
829 		 * We will disable all channels that do not match our
830 		 * received regulatory rule unless the hint is coming
831 		 * from a Country IE and the Country IE had no information
832 		 * about a band. The IEEE 802.11 spec allows for an AP
833 		 * to send only a subset of the regulatory rules allowed,
834 		 * so an AP in the US that only supports 2.4 GHz may only send
835 		 * a country IE with information for the 2.4 GHz band
836 		 * while 5 GHz is still supported.
837 		 */
838 		if (initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE &&
839 		    r == -ERANGE)
840 			return;
841 
842 		REG_DBG_PRINT("Disabling freq %d MHz\n", chan->center_freq);
843 		chan->flags = IEEE80211_CHAN_DISABLED;
844 		return;
845 	}
846 
847 	chan_reg_rule_print_dbg(chan, desired_bw_khz, reg_rule);
848 
849 	power_rule = &reg_rule->power_rule;
850 	freq_range = &reg_rule->freq_range;
851 
852 	if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
853 		bw_flags = IEEE80211_CHAN_NO_HT40;
854 
855 	if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
856 	    request_wiphy && request_wiphy == wiphy &&
857 	    request_wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY) {
858 		/*
859 		 * This guarantees the driver's requested regulatory domain
860 		 * will always be used as a base for further regulatory
861 		 * settings
862 		 */
863 		chan->flags = chan->orig_flags =
864 			map_regdom_flags(reg_rule->flags) | bw_flags;
865 		chan->max_antenna_gain = chan->orig_mag =
866 			(int) MBI_TO_DBI(power_rule->max_antenna_gain);
867 		chan->max_power = chan->orig_mpwr =
868 			(int) MBM_TO_DBM(power_rule->max_eirp);
869 		return;
870 	}
871 
872 	chan->beacon_found = false;
873 	chan->flags = flags | bw_flags | map_regdom_flags(reg_rule->flags);
874 	chan->max_antenna_gain = min(chan->orig_mag,
875 		(int) MBI_TO_DBI(power_rule->max_antenna_gain));
876 	if (chan->orig_mpwr)
877 		chan->max_power = min(chan->orig_mpwr,
878 			(int) MBM_TO_DBM(power_rule->max_eirp));
879 	else
880 		chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
881 }
882 
883 static void handle_band(struct wiphy *wiphy,
884 			enum ieee80211_band band,
885 			enum nl80211_reg_initiator initiator)
886 {
887 	unsigned int i;
888 	struct ieee80211_supported_band *sband;
889 
890 	BUG_ON(!wiphy->bands[band]);
891 	sband = wiphy->bands[band];
892 
893 	for (i = 0; i < sband->n_channels; i++)
894 		handle_channel(wiphy, initiator, band, i);
895 }
896 
897 static bool ignore_reg_update(struct wiphy *wiphy,
898 			      enum nl80211_reg_initiator initiator)
899 {
900 	if (!last_request) {
901 		REG_DBG_PRINT("Ignoring regulatory request %s since "
902 			      "last_request is not set\n",
903 			      reg_initiator_name(initiator));
904 		return true;
905 	}
906 
907 	if (initiator == NL80211_REGDOM_SET_BY_CORE &&
908 	    wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY) {
909 		REG_DBG_PRINT("Ignoring regulatory request %s "
910 			      "since the driver uses its own custom "
911 			      "regulatory domain\n",
912 			      reg_initiator_name(initiator));
913 		return true;
914 	}
915 
916 	/*
917 	 * wiphy->regd will be set once the device has its own
918 	 * desired regulatory domain set
919 	 */
920 	if (wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY && !wiphy->regd &&
921 	    initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
922 	    !is_world_regdom(last_request->alpha2)) {
923 		REG_DBG_PRINT("Ignoring regulatory request %s "
924 			      "since the driver requires its own regulatory "
925 			      "domain to be set first\n",
926 			      reg_initiator_name(initiator));
927 		return true;
928 	}
929 
930 	return false;
931 }
932 
933 static void handle_reg_beacon(struct wiphy *wiphy,
934 			      unsigned int chan_idx,
935 			      struct reg_beacon *reg_beacon)
936 {
937 	struct ieee80211_supported_band *sband;
938 	struct ieee80211_channel *chan;
939 	bool channel_changed = false;
940 	struct ieee80211_channel chan_before;
941 
942 	assert_cfg80211_lock();
943 
944 	sband = wiphy->bands[reg_beacon->chan.band];
945 	chan = &sband->channels[chan_idx];
946 
947 	if (likely(chan->center_freq != reg_beacon->chan.center_freq))
948 		return;
949 
950 	if (chan->beacon_found)
951 		return;
952 
953 	chan->beacon_found = true;
954 
955 	if (wiphy->flags & WIPHY_FLAG_DISABLE_BEACON_HINTS)
956 		return;
957 
958 	chan_before.center_freq = chan->center_freq;
959 	chan_before.flags = chan->flags;
960 
961 	if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN) {
962 		chan->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
963 		channel_changed = true;
964 	}
965 
966 	if (chan->flags & IEEE80211_CHAN_NO_IBSS) {
967 		chan->flags &= ~IEEE80211_CHAN_NO_IBSS;
968 		channel_changed = true;
969 	}
970 
971 	if (channel_changed)
972 		nl80211_send_beacon_hint_event(wiphy, &chan_before, chan);
973 }
974 
975 /*
976  * Called when a scan on a wiphy finds a beacon on
977  * new channel
978  */
979 static void wiphy_update_new_beacon(struct wiphy *wiphy,
980 				    struct reg_beacon *reg_beacon)
981 {
982 	unsigned int i;
983 	struct ieee80211_supported_band *sband;
984 
985 	assert_cfg80211_lock();
986 
987 	if (!wiphy->bands[reg_beacon->chan.band])
988 		return;
989 
990 	sband = wiphy->bands[reg_beacon->chan.band];
991 
992 	for (i = 0; i < sband->n_channels; i++)
993 		handle_reg_beacon(wiphy, i, reg_beacon);
994 }
995 
996 /*
997  * Called upon reg changes or a new wiphy is added
998  */
999 static void wiphy_update_beacon_reg(struct wiphy *wiphy)
1000 {
1001 	unsigned int i;
1002 	struct ieee80211_supported_band *sband;
1003 	struct reg_beacon *reg_beacon;
1004 
1005 	assert_cfg80211_lock();
1006 
1007 	if (list_empty(&reg_beacon_list))
1008 		return;
1009 
1010 	list_for_each_entry(reg_beacon, &reg_beacon_list, list) {
1011 		if (!wiphy->bands[reg_beacon->chan.band])
1012 			continue;
1013 		sband = wiphy->bands[reg_beacon->chan.band];
1014 		for (i = 0; i < sband->n_channels; i++)
1015 			handle_reg_beacon(wiphy, i, reg_beacon);
1016 	}
1017 }
1018 
1019 static bool reg_is_world_roaming(struct wiphy *wiphy)
1020 {
1021 	if (is_world_regdom(cfg80211_regdomain->alpha2) ||
1022 	    (wiphy->regd && is_world_regdom(wiphy->regd->alpha2)))
1023 		return true;
1024 	if (last_request &&
1025 	    last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1026 	    wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY)
1027 		return true;
1028 	return false;
1029 }
1030 
1031 /* Reap the advantages of previously found beacons */
1032 static void reg_process_beacons(struct wiphy *wiphy)
1033 {
1034 	/*
1035 	 * Means we are just firing up cfg80211, so no beacons would
1036 	 * have been processed yet.
1037 	 */
1038 	if (!last_request)
1039 		return;
1040 	if (!reg_is_world_roaming(wiphy))
1041 		return;
1042 	wiphy_update_beacon_reg(wiphy);
1043 }
1044 
1045 static bool is_ht40_not_allowed(struct ieee80211_channel *chan)
1046 {
1047 	if (!chan)
1048 		return true;
1049 	if (chan->flags & IEEE80211_CHAN_DISABLED)
1050 		return true;
1051 	/* This would happen when regulatory rules disallow HT40 completely */
1052 	if (IEEE80211_CHAN_NO_HT40 == (chan->flags & (IEEE80211_CHAN_NO_HT40)))
1053 		return true;
1054 	return false;
1055 }
1056 
1057 static void reg_process_ht_flags_channel(struct wiphy *wiphy,
1058 					 enum ieee80211_band band,
1059 					 unsigned int chan_idx)
1060 {
1061 	struct ieee80211_supported_band *sband;
1062 	struct ieee80211_channel *channel;
1063 	struct ieee80211_channel *channel_before = NULL, *channel_after = NULL;
1064 	unsigned int i;
1065 
1066 	assert_cfg80211_lock();
1067 
1068 	sband = wiphy->bands[band];
1069 	BUG_ON(chan_idx >= sband->n_channels);
1070 	channel = &sband->channels[chan_idx];
1071 
1072 	if (is_ht40_not_allowed(channel)) {
1073 		channel->flags |= IEEE80211_CHAN_NO_HT40;
1074 		return;
1075 	}
1076 
1077 	/*
1078 	 * We need to ensure the extension channels exist to
1079 	 * be able to use HT40- or HT40+, this finds them (or not)
1080 	 */
1081 	for (i = 0; i < sband->n_channels; i++) {
1082 		struct ieee80211_channel *c = &sband->channels[i];
1083 		if (c->center_freq == (channel->center_freq - 20))
1084 			channel_before = c;
1085 		if (c->center_freq == (channel->center_freq + 20))
1086 			channel_after = c;
1087 	}
1088 
1089 	/*
1090 	 * Please note that this assumes target bandwidth is 20 MHz,
1091 	 * if that ever changes we also need to change the below logic
1092 	 * to include that as well.
1093 	 */
1094 	if (is_ht40_not_allowed(channel_before))
1095 		channel->flags |= IEEE80211_CHAN_NO_HT40MINUS;
1096 	else
1097 		channel->flags &= ~IEEE80211_CHAN_NO_HT40MINUS;
1098 
1099 	if (is_ht40_not_allowed(channel_after))
1100 		channel->flags |= IEEE80211_CHAN_NO_HT40PLUS;
1101 	else
1102 		channel->flags &= ~IEEE80211_CHAN_NO_HT40PLUS;
1103 }
1104 
1105 static void reg_process_ht_flags_band(struct wiphy *wiphy,
1106 				      enum ieee80211_band band)
1107 {
1108 	unsigned int i;
1109 	struct ieee80211_supported_band *sband;
1110 
1111 	BUG_ON(!wiphy->bands[band]);
1112 	sband = wiphy->bands[band];
1113 
1114 	for (i = 0; i < sband->n_channels; i++)
1115 		reg_process_ht_flags_channel(wiphy, band, i);
1116 }
1117 
1118 static void reg_process_ht_flags(struct wiphy *wiphy)
1119 {
1120 	enum ieee80211_band band;
1121 
1122 	if (!wiphy)
1123 		return;
1124 
1125 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1126 		if (wiphy->bands[band])
1127 			reg_process_ht_flags_band(wiphy, band);
1128 	}
1129 
1130 }
1131 
1132 static void wiphy_update_regulatory(struct wiphy *wiphy,
1133 				    enum nl80211_reg_initiator initiator)
1134 {
1135 	enum ieee80211_band band;
1136 
1137 	assert_reg_lock();
1138 
1139 	if (ignore_reg_update(wiphy, initiator))
1140 		return;
1141 
1142 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1143 		if (wiphy->bands[band])
1144 			handle_band(wiphy, band, initiator);
1145 	}
1146 
1147 	reg_process_beacons(wiphy);
1148 	reg_process_ht_flags(wiphy);
1149 	if (wiphy->reg_notifier)
1150 		wiphy->reg_notifier(wiphy, last_request);
1151 }
1152 
1153 void regulatory_update(struct wiphy *wiphy,
1154 		       enum nl80211_reg_initiator setby)
1155 {
1156 	mutex_lock(&reg_mutex);
1157 	wiphy_update_regulatory(wiphy, setby);
1158 	mutex_unlock(&reg_mutex);
1159 }
1160 
1161 static void update_all_wiphy_regulatory(enum nl80211_reg_initiator initiator)
1162 {
1163 	struct cfg80211_registered_device *rdev;
1164 
1165 	list_for_each_entry(rdev, &cfg80211_rdev_list, list)
1166 		wiphy_update_regulatory(&rdev->wiphy, initiator);
1167 }
1168 
1169 static void handle_channel_custom(struct wiphy *wiphy,
1170 				  enum ieee80211_band band,
1171 				  unsigned int chan_idx,
1172 				  const struct ieee80211_regdomain *regd)
1173 {
1174 	int r;
1175 	u32 desired_bw_khz = MHZ_TO_KHZ(20);
1176 	u32 bw_flags = 0;
1177 	const struct ieee80211_reg_rule *reg_rule = NULL;
1178 	const struct ieee80211_power_rule *power_rule = NULL;
1179 	const struct ieee80211_freq_range *freq_range = NULL;
1180 	struct ieee80211_supported_band *sband;
1181 	struct ieee80211_channel *chan;
1182 
1183 	assert_reg_lock();
1184 
1185 	sband = wiphy->bands[band];
1186 	BUG_ON(chan_idx >= sband->n_channels);
1187 	chan = &sband->channels[chan_idx];
1188 
1189 	r = freq_reg_info_regd(wiphy,
1190 			       MHZ_TO_KHZ(chan->center_freq),
1191 			       desired_bw_khz,
1192 			       &reg_rule,
1193 			       regd);
1194 
1195 	if (r) {
1196 		REG_DBG_PRINT("Disabling freq %d MHz as custom "
1197 			      "regd has no rule that fits a %d MHz "
1198 			      "wide channel\n",
1199 			      chan->center_freq,
1200 			      KHZ_TO_MHZ(desired_bw_khz));
1201 		chan->flags = IEEE80211_CHAN_DISABLED;
1202 		return;
1203 	}
1204 
1205 	chan_reg_rule_print_dbg(chan, desired_bw_khz, reg_rule);
1206 
1207 	power_rule = &reg_rule->power_rule;
1208 	freq_range = &reg_rule->freq_range;
1209 
1210 	if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
1211 		bw_flags = IEEE80211_CHAN_NO_HT40;
1212 
1213 	chan->flags |= map_regdom_flags(reg_rule->flags) | bw_flags;
1214 	chan->max_antenna_gain = (int) MBI_TO_DBI(power_rule->max_antenna_gain);
1215 	chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
1216 }
1217 
1218 static void handle_band_custom(struct wiphy *wiphy, enum ieee80211_band band,
1219 			       const struct ieee80211_regdomain *regd)
1220 {
1221 	unsigned int i;
1222 	struct ieee80211_supported_band *sband;
1223 
1224 	BUG_ON(!wiphy->bands[band]);
1225 	sband = wiphy->bands[band];
1226 
1227 	for (i = 0; i < sband->n_channels; i++)
1228 		handle_channel_custom(wiphy, band, i, regd);
1229 }
1230 
1231 /* Used by drivers prior to wiphy registration */
1232 void wiphy_apply_custom_regulatory(struct wiphy *wiphy,
1233 				   const struct ieee80211_regdomain *regd)
1234 {
1235 	enum ieee80211_band band;
1236 	unsigned int bands_set = 0;
1237 
1238 	mutex_lock(&reg_mutex);
1239 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1240 		if (!wiphy->bands[band])
1241 			continue;
1242 		handle_band_custom(wiphy, band, regd);
1243 		bands_set++;
1244 	}
1245 	mutex_unlock(&reg_mutex);
1246 
1247 	/*
1248 	 * no point in calling this if it won't have any effect
1249 	 * on your device's supportd bands.
1250 	 */
1251 	WARN_ON(!bands_set);
1252 }
1253 EXPORT_SYMBOL(wiphy_apply_custom_regulatory);
1254 
1255 /*
1256  * Return value which can be used by ignore_request() to indicate
1257  * it has been determined we should intersect two regulatory domains
1258  */
1259 #define REG_INTERSECT	1
1260 
1261 /* This has the logic which determines when a new request
1262  * should be ignored. */
1263 static int ignore_request(struct wiphy *wiphy,
1264 			  struct regulatory_request *pending_request)
1265 {
1266 	struct wiphy *last_wiphy = NULL;
1267 
1268 	assert_cfg80211_lock();
1269 
1270 	/* All initial requests are respected */
1271 	if (!last_request)
1272 		return 0;
1273 
1274 	switch (pending_request->initiator) {
1275 	case NL80211_REGDOM_SET_BY_CORE:
1276 		return 0;
1277 	case NL80211_REGDOM_SET_BY_COUNTRY_IE:
1278 
1279 		last_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
1280 
1281 		if (unlikely(!is_an_alpha2(pending_request->alpha2)))
1282 			return -EINVAL;
1283 		if (last_request->initiator ==
1284 		    NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1285 			if (last_wiphy != wiphy) {
1286 				/*
1287 				 * Two cards with two APs claiming different
1288 				 * Country IE alpha2s. We could
1289 				 * intersect them, but that seems unlikely
1290 				 * to be correct. Reject second one for now.
1291 				 */
1292 				if (regdom_changes(pending_request->alpha2))
1293 					return -EOPNOTSUPP;
1294 				return -EALREADY;
1295 			}
1296 			/*
1297 			 * Two consecutive Country IE hints on the same wiphy.
1298 			 * This should be picked up early by the driver/stack
1299 			 */
1300 			if (WARN_ON(regdom_changes(pending_request->alpha2)))
1301 				return 0;
1302 			return -EALREADY;
1303 		}
1304 		return 0;
1305 	case NL80211_REGDOM_SET_BY_DRIVER:
1306 		if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE) {
1307 			if (regdom_changes(pending_request->alpha2))
1308 				return 0;
1309 			return -EALREADY;
1310 		}
1311 
1312 		/*
1313 		 * This would happen if you unplug and plug your card
1314 		 * back in or if you add a new device for which the previously
1315 		 * loaded card also agrees on the regulatory domain.
1316 		 */
1317 		if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1318 		    !regdom_changes(pending_request->alpha2))
1319 			return -EALREADY;
1320 
1321 		return REG_INTERSECT;
1322 	case NL80211_REGDOM_SET_BY_USER:
1323 		if (last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE)
1324 			return REG_INTERSECT;
1325 		/*
1326 		 * If the user knows better the user should set the regdom
1327 		 * to their country before the IE is picked up
1328 		 */
1329 		if (last_request->initiator == NL80211_REGDOM_SET_BY_USER &&
1330 			  last_request->intersect)
1331 			return -EOPNOTSUPP;
1332 		/*
1333 		 * Process user requests only after previous user/driver/core
1334 		 * requests have been processed
1335 		 */
1336 		if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE ||
1337 		    last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER ||
1338 		    last_request->initiator == NL80211_REGDOM_SET_BY_USER) {
1339 			if (regdom_changes(last_request->alpha2))
1340 				return -EAGAIN;
1341 		}
1342 
1343 		if (!regdom_changes(pending_request->alpha2))
1344 			return -EALREADY;
1345 
1346 		return 0;
1347 	}
1348 
1349 	return -EINVAL;
1350 }
1351 
1352 static void reg_set_request_processed(void)
1353 {
1354 	bool need_more_processing = false;
1355 
1356 	last_request->processed = true;
1357 
1358 	spin_lock(&reg_requests_lock);
1359 	if (!list_empty(&reg_requests_list))
1360 		need_more_processing = true;
1361 	spin_unlock(&reg_requests_lock);
1362 
1363 	if (last_request->initiator == NL80211_REGDOM_SET_BY_USER)
1364 		cancel_delayed_work_sync(&reg_timeout);
1365 
1366 	if (need_more_processing)
1367 		schedule_work(&reg_work);
1368 }
1369 
1370 /**
1371  * __regulatory_hint - hint to the wireless core a regulatory domain
1372  * @wiphy: if the hint comes from country information from an AP, this
1373  *	is required to be set to the wiphy that received the information
1374  * @pending_request: the regulatory request currently being processed
1375  *
1376  * The Wireless subsystem can use this function to hint to the wireless core
1377  * what it believes should be the current regulatory domain.
1378  *
1379  * Returns zero if all went fine, %-EALREADY if a regulatory domain had
1380  * already been set or other standard error codes.
1381  *
1382  * Caller must hold &cfg80211_mutex and &reg_mutex
1383  */
1384 static int __regulatory_hint(struct wiphy *wiphy,
1385 			     struct regulatory_request *pending_request)
1386 {
1387 	bool intersect = false;
1388 	int r = 0;
1389 
1390 	assert_cfg80211_lock();
1391 
1392 	r = ignore_request(wiphy, pending_request);
1393 
1394 	if (r == REG_INTERSECT) {
1395 		if (pending_request->initiator ==
1396 		    NL80211_REGDOM_SET_BY_DRIVER) {
1397 			r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1398 			if (r) {
1399 				kfree(pending_request);
1400 				return r;
1401 			}
1402 		}
1403 		intersect = true;
1404 	} else if (r) {
1405 		/*
1406 		 * If the regulatory domain being requested by the
1407 		 * driver has already been set just copy it to the
1408 		 * wiphy
1409 		 */
1410 		if (r == -EALREADY &&
1411 		    pending_request->initiator ==
1412 		    NL80211_REGDOM_SET_BY_DRIVER) {
1413 			r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1414 			if (r) {
1415 				kfree(pending_request);
1416 				return r;
1417 			}
1418 			r = -EALREADY;
1419 			goto new_request;
1420 		}
1421 		kfree(pending_request);
1422 		return r;
1423 	}
1424 
1425 new_request:
1426 	if (last_request != &core_request_world)
1427 		kfree(last_request);
1428 
1429 	last_request = pending_request;
1430 	last_request->intersect = intersect;
1431 
1432 	pending_request = NULL;
1433 
1434 	if (last_request->initiator == NL80211_REGDOM_SET_BY_USER) {
1435 		user_alpha2[0] = last_request->alpha2[0];
1436 		user_alpha2[1] = last_request->alpha2[1];
1437 	}
1438 
1439 	/* When r == REG_INTERSECT we do need to call CRDA */
1440 	if (r < 0) {
1441 		/*
1442 		 * Since CRDA will not be called in this case as we already
1443 		 * have applied the requested regulatory domain before we just
1444 		 * inform userspace we have processed the request
1445 		 */
1446 		if (r == -EALREADY) {
1447 			nl80211_send_reg_change_event(last_request);
1448 			reg_set_request_processed();
1449 		}
1450 		return r;
1451 	}
1452 
1453 	return call_crda(last_request->alpha2);
1454 }
1455 
1456 /* This processes *all* regulatory hints */
1457 static void reg_process_hint(struct regulatory_request *reg_request)
1458 {
1459 	int r = 0;
1460 	struct wiphy *wiphy = NULL;
1461 	enum nl80211_reg_initiator initiator = reg_request->initiator;
1462 
1463 	BUG_ON(!reg_request->alpha2);
1464 
1465 	if (wiphy_idx_valid(reg_request->wiphy_idx))
1466 		wiphy = wiphy_idx_to_wiphy(reg_request->wiphy_idx);
1467 
1468 	if (reg_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1469 	    !wiphy) {
1470 		kfree(reg_request);
1471 		return;
1472 	}
1473 
1474 	r = __regulatory_hint(wiphy, reg_request);
1475 	/* This is required so that the orig_* parameters are saved */
1476 	if (r == -EALREADY && wiphy &&
1477 	    wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY) {
1478 		wiphy_update_regulatory(wiphy, initiator);
1479 		return;
1480 	}
1481 
1482 	/*
1483 	 * We only time out user hints, given that they should be the only
1484 	 * source of bogus requests.
1485 	 */
1486 	if (r != -EALREADY &&
1487 	    reg_request->initiator == NL80211_REGDOM_SET_BY_USER)
1488 		schedule_delayed_work(&reg_timeout, msecs_to_jiffies(3142));
1489 }
1490 
1491 /*
1492  * Processes regulatory hints, this is all the NL80211_REGDOM_SET_BY_*
1493  * Regulatory hints come on a first come first serve basis and we
1494  * must process each one atomically.
1495  */
1496 static void reg_process_pending_hints(void)
1497 {
1498 	struct regulatory_request *reg_request;
1499 
1500 	mutex_lock(&cfg80211_mutex);
1501 	mutex_lock(&reg_mutex);
1502 
1503 	/* When last_request->processed becomes true this will be rescheduled */
1504 	if (last_request && !last_request->processed) {
1505 		REG_DBG_PRINT("Pending regulatory request, waiting "
1506 			      "for it to be processed...\n");
1507 		goto out;
1508 	}
1509 
1510 	spin_lock(&reg_requests_lock);
1511 
1512 	if (list_empty(&reg_requests_list)) {
1513 		spin_unlock(&reg_requests_lock);
1514 		goto out;
1515 	}
1516 
1517 	reg_request = list_first_entry(&reg_requests_list,
1518 				       struct regulatory_request,
1519 				       list);
1520 	list_del_init(&reg_request->list);
1521 
1522 	spin_unlock(&reg_requests_lock);
1523 
1524 	reg_process_hint(reg_request);
1525 
1526 out:
1527 	mutex_unlock(&reg_mutex);
1528 	mutex_unlock(&cfg80211_mutex);
1529 }
1530 
1531 /* Processes beacon hints -- this has nothing to do with country IEs */
1532 static void reg_process_pending_beacon_hints(void)
1533 {
1534 	struct cfg80211_registered_device *rdev;
1535 	struct reg_beacon *pending_beacon, *tmp;
1536 
1537 	/*
1538 	 * No need to hold the reg_mutex here as we just touch wiphys
1539 	 * and do not read or access regulatory variables.
1540 	 */
1541 	mutex_lock(&cfg80211_mutex);
1542 
1543 	/* This goes through the _pending_ beacon list */
1544 	spin_lock_bh(&reg_pending_beacons_lock);
1545 
1546 	if (list_empty(&reg_pending_beacons)) {
1547 		spin_unlock_bh(&reg_pending_beacons_lock);
1548 		goto out;
1549 	}
1550 
1551 	list_for_each_entry_safe(pending_beacon, tmp,
1552 				 &reg_pending_beacons, list) {
1553 
1554 		list_del_init(&pending_beacon->list);
1555 
1556 		/* Applies the beacon hint to current wiphys */
1557 		list_for_each_entry(rdev, &cfg80211_rdev_list, list)
1558 			wiphy_update_new_beacon(&rdev->wiphy, pending_beacon);
1559 
1560 		/* Remembers the beacon hint for new wiphys or reg changes */
1561 		list_add_tail(&pending_beacon->list, &reg_beacon_list);
1562 	}
1563 
1564 	spin_unlock_bh(&reg_pending_beacons_lock);
1565 out:
1566 	mutex_unlock(&cfg80211_mutex);
1567 }
1568 
1569 static void reg_todo(struct work_struct *work)
1570 {
1571 	reg_process_pending_hints();
1572 	reg_process_pending_beacon_hints();
1573 }
1574 
1575 static void queue_regulatory_request(struct regulatory_request *request)
1576 {
1577 	if (isalpha(request->alpha2[0]))
1578 		request->alpha2[0] = toupper(request->alpha2[0]);
1579 	if (isalpha(request->alpha2[1]))
1580 		request->alpha2[1] = toupper(request->alpha2[1]);
1581 
1582 	spin_lock(&reg_requests_lock);
1583 	list_add_tail(&request->list, &reg_requests_list);
1584 	spin_unlock(&reg_requests_lock);
1585 
1586 	schedule_work(&reg_work);
1587 }
1588 
1589 /*
1590  * Core regulatory hint -- happens during cfg80211_init()
1591  * and when we restore regulatory settings.
1592  */
1593 static int regulatory_hint_core(const char *alpha2)
1594 {
1595 	struct regulatory_request *request;
1596 
1597 	request = kzalloc(sizeof(struct regulatory_request),
1598 			  GFP_KERNEL);
1599 	if (!request)
1600 		return -ENOMEM;
1601 
1602 	request->alpha2[0] = alpha2[0];
1603 	request->alpha2[1] = alpha2[1];
1604 	request->initiator = NL80211_REGDOM_SET_BY_CORE;
1605 
1606 	queue_regulatory_request(request);
1607 
1608 	return 0;
1609 }
1610 
1611 /* User hints */
1612 int regulatory_hint_user(const char *alpha2)
1613 {
1614 	struct regulatory_request *request;
1615 
1616 	BUG_ON(!alpha2);
1617 
1618 	request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1619 	if (!request)
1620 		return -ENOMEM;
1621 
1622 	request->wiphy_idx = WIPHY_IDX_STALE;
1623 	request->alpha2[0] = alpha2[0];
1624 	request->alpha2[1] = alpha2[1];
1625 	request->initiator = NL80211_REGDOM_SET_BY_USER;
1626 
1627 	queue_regulatory_request(request);
1628 
1629 	return 0;
1630 }
1631 
1632 /* Driver hints */
1633 int regulatory_hint(struct wiphy *wiphy, const char *alpha2)
1634 {
1635 	struct regulatory_request *request;
1636 
1637 	BUG_ON(!alpha2);
1638 	BUG_ON(!wiphy);
1639 
1640 	request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1641 	if (!request)
1642 		return -ENOMEM;
1643 
1644 	request->wiphy_idx = get_wiphy_idx(wiphy);
1645 
1646 	/* Must have registered wiphy first */
1647 	BUG_ON(!wiphy_idx_valid(request->wiphy_idx));
1648 
1649 	request->alpha2[0] = alpha2[0];
1650 	request->alpha2[1] = alpha2[1];
1651 	request->initiator = NL80211_REGDOM_SET_BY_DRIVER;
1652 
1653 	queue_regulatory_request(request);
1654 
1655 	return 0;
1656 }
1657 EXPORT_SYMBOL(regulatory_hint);
1658 
1659 /*
1660  * We hold wdev_lock() here so we cannot hold cfg80211_mutex() and
1661  * therefore cannot iterate over the rdev list here.
1662  */
1663 void regulatory_hint_11d(struct wiphy *wiphy,
1664 			 enum ieee80211_band band,
1665 			 u8 *country_ie,
1666 			 u8 country_ie_len)
1667 {
1668 	char alpha2[2];
1669 	enum environment_cap env = ENVIRON_ANY;
1670 	struct regulatory_request *request;
1671 
1672 	mutex_lock(&reg_mutex);
1673 
1674 	if (unlikely(!last_request))
1675 		goto out;
1676 
1677 	/* IE len must be evenly divisible by 2 */
1678 	if (country_ie_len & 0x01)
1679 		goto out;
1680 
1681 	if (country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN)
1682 		goto out;
1683 
1684 	alpha2[0] = country_ie[0];
1685 	alpha2[1] = country_ie[1];
1686 
1687 	if (country_ie[2] == 'I')
1688 		env = ENVIRON_INDOOR;
1689 	else if (country_ie[2] == 'O')
1690 		env = ENVIRON_OUTDOOR;
1691 
1692 	/*
1693 	 * We will run this only upon a successful connection on cfg80211.
1694 	 * We leave conflict resolution to the workqueue, where can hold
1695 	 * cfg80211_mutex.
1696 	 */
1697 	if (likely(last_request->initiator ==
1698 	    NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1699 	    wiphy_idx_valid(last_request->wiphy_idx)))
1700 		goto out;
1701 
1702 	request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1703 	if (!request)
1704 		goto out;
1705 
1706 	request->wiphy_idx = get_wiphy_idx(wiphy);
1707 	request->alpha2[0] = alpha2[0];
1708 	request->alpha2[1] = alpha2[1];
1709 	request->initiator = NL80211_REGDOM_SET_BY_COUNTRY_IE;
1710 	request->country_ie_env = env;
1711 
1712 	mutex_unlock(&reg_mutex);
1713 
1714 	queue_regulatory_request(request);
1715 
1716 	return;
1717 
1718 out:
1719 	mutex_unlock(&reg_mutex);
1720 }
1721 
1722 static void restore_alpha2(char *alpha2, bool reset_user)
1723 {
1724 	/* indicates there is no alpha2 to consider for restoration */
1725 	alpha2[0] = '9';
1726 	alpha2[1] = '7';
1727 
1728 	/* The user setting has precedence over the module parameter */
1729 	if (is_user_regdom_saved()) {
1730 		/* Unless we're asked to ignore it and reset it */
1731 		if (reset_user) {
1732 			REG_DBG_PRINT("Restoring regulatory settings "
1733 			       "including user preference\n");
1734 			user_alpha2[0] = '9';
1735 			user_alpha2[1] = '7';
1736 
1737 			/*
1738 			 * If we're ignoring user settings, we still need to
1739 			 * check the module parameter to ensure we put things
1740 			 * back as they were for a full restore.
1741 			 */
1742 			if (!is_world_regdom(ieee80211_regdom)) {
1743 				REG_DBG_PRINT("Keeping preference on "
1744 				       "module parameter ieee80211_regdom: %c%c\n",
1745 				       ieee80211_regdom[0],
1746 				       ieee80211_regdom[1]);
1747 				alpha2[0] = ieee80211_regdom[0];
1748 				alpha2[1] = ieee80211_regdom[1];
1749 			}
1750 		} else {
1751 			REG_DBG_PRINT("Restoring regulatory settings "
1752 			       "while preserving user preference for: %c%c\n",
1753 			       user_alpha2[0],
1754 			       user_alpha2[1]);
1755 			alpha2[0] = user_alpha2[0];
1756 			alpha2[1] = user_alpha2[1];
1757 		}
1758 	} else if (!is_world_regdom(ieee80211_regdom)) {
1759 		REG_DBG_PRINT("Keeping preference on "
1760 		       "module parameter ieee80211_regdom: %c%c\n",
1761 		       ieee80211_regdom[0],
1762 		       ieee80211_regdom[1]);
1763 		alpha2[0] = ieee80211_regdom[0];
1764 		alpha2[1] = ieee80211_regdom[1];
1765 	} else
1766 		REG_DBG_PRINT("Restoring regulatory settings\n");
1767 }
1768 
1769 /*
1770  * Restoring regulatory settings involves ingoring any
1771  * possibly stale country IE information and user regulatory
1772  * settings if so desired, this includes any beacon hints
1773  * learned as we could have traveled outside to another country
1774  * after disconnection. To restore regulatory settings we do
1775  * exactly what we did at bootup:
1776  *
1777  *   - send a core regulatory hint
1778  *   - send a user regulatory hint if applicable
1779  *
1780  * Device drivers that send a regulatory hint for a specific country
1781  * keep their own regulatory domain on wiphy->regd so that does does
1782  * not need to be remembered.
1783  */
1784 static void restore_regulatory_settings(bool reset_user)
1785 {
1786 	char alpha2[2];
1787 	struct reg_beacon *reg_beacon, *btmp;
1788 	struct regulatory_request *reg_request, *tmp;
1789 	LIST_HEAD(tmp_reg_req_list);
1790 
1791 	mutex_lock(&cfg80211_mutex);
1792 	mutex_lock(&reg_mutex);
1793 
1794 	reset_regdomains(true);
1795 	restore_alpha2(alpha2, reset_user);
1796 
1797 	/*
1798 	 * If there's any pending requests we simply
1799 	 * stash them to a temporary pending queue and
1800 	 * add then after we've restored regulatory
1801 	 * settings.
1802 	 */
1803 	spin_lock(&reg_requests_lock);
1804 	if (!list_empty(&reg_requests_list)) {
1805 		list_for_each_entry_safe(reg_request, tmp,
1806 					 &reg_requests_list, list) {
1807 			if (reg_request->initiator !=
1808 			    NL80211_REGDOM_SET_BY_USER)
1809 				continue;
1810 			list_del(&reg_request->list);
1811 			list_add_tail(&reg_request->list, &tmp_reg_req_list);
1812 		}
1813 	}
1814 	spin_unlock(&reg_requests_lock);
1815 
1816 	/* Clear beacon hints */
1817 	spin_lock_bh(&reg_pending_beacons_lock);
1818 	if (!list_empty(&reg_pending_beacons)) {
1819 		list_for_each_entry_safe(reg_beacon, btmp,
1820 					 &reg_pending_beacons, list) {
1821 			list_del(&reg_beacon->list);
1822 			kfree(reg_beacon);
1823 		}
1824 	}
1825 	spin_unlock_bh(&reg_pending_beacons_lock);
1826 
1827 	if (!list_empty(&reg_beacon_list)) {
1828 		list_for_each_entry_safe(reg_beacon, btmp,
1829 					 &reg_beacon_list, list) {
1830 			list_del(&reg_beacon->list);
1831 			kfree(reg_beacon);
1832 		}
1833 	}
1834 
1835 	/* First restore to the basic regulatory settings */
1836 	cfg80211_regdomain = cfg80211_world_regdom;
1837 
1838 	mutex_unlock(&reg_mutex);
1839 	mutex_unlock(&cfg80211_mutex);
1840 
1841 	regulatory_hint_core(cfg80211_regdomain->alpha2);
1842 
1843 	/*
1844 	 * This restores the ieee80211_regdom module parameter
1845 	 * preference or the last user requested regulatory
1846 	 * settings, user regulatory settings takes precedence.
1847 	 */
1848 	if (is_an_alpha2(alpha2))
1849 		regulatory_hint_user(user_alpha2);
1850 
1851 	if (list_empty(&tmp_reg_req_list))
1852 		return;
1853 
1854 	mutex_lock(&cfg80211_mutex);
1855 	mutex_lock(&reg_mutex);
1856 
1857 	spin_lock(&reg_requests_lock);
1858 	list_for_each_entry_safe(reg_request, tmp, &tmp_reg_req_list, list) {
1859 		REG_DBG_PRINT("Adding request for country %c%c back "
1860 			      "into the queue\n",
1861 			      reg_request->alpha2[0],
1862 			      reg_request->alpha2[1]);
1863 		list_del(&reg_request->list);
1864 		list_add_tail(&reg_request->list, &reg_requests_list);
1865 	}
1866 	spin_unlock(&reg_requests_lock);
1867 
1868 	mutex_unlock(&reg_mutex);
1869 	mutex_unlock(&cfg80211_mutex);
1870 
1871 	REG_DBG_PRINT("Kicking the queue\n");
1872 
1873 	schedule_work(&reg_work);
1874 }
1875 
1876 void regulatory_hint_disconnect(void)
1877 {
1878 	REG_DBG_PRINT("All devices are disconnected, going to "
1879 		      "restore regulatory settings\n");
1880 	restore_regulatory_settings(false);
1881 }
1882 
1883 static bool freq_is_chan_12_13_14(u16 freq)
1884 {
1885 	if (freq == ieee80211_channel_to_frequency(12, IEEE80211_BAND_2GHZ) ||
1886 	    freq == ieee80211_channel_to_frequency(13, IEEE80211_BAND_2GHZ) ||
1887 	    freq == ieee80211_channel_to_frequency(14, IEEE80211_BAND_2GHZ))
1888 		return true;
1889 	return false;
1890 }
1891 
1892 int regulatory_hint_found_beacon(struct wiphy *wiphy,
1893 				 struct ieee80211_channel *beacon_chan,
1894 				 gfp_t gfp)
1895 {
1896 	struct reg_beacon *reg_beacon;
1897 
1898 	if (likely((beacon_chan->beacon_found ||
1899 	    (beacon_chan->flags & IEEE80211_CHAN_RADAR) ||
1900 	    (beacon_chan->band == IEEE80211_BAND_2GHZ &&
1901 	     !freq_is_chan_12_13_14(beacon_chan->center_freq)))))
1902 		return 0;
1903 
1904 	reg_beacon = kzalloc(sizeof(struct reg_beacon), gfp);
1905 	if (!reg_beacon)
1906 		return -ENOMEM;
1907 
1908 	REG_DBG_PRINT("Found new beacon on "
1909 		      "frequency: %d MHz (Ch %d) on %s\n",
1910 		      beacon_chan->center_freq,
1911 		      ieee80211_frequency_to_channel(beacon_chan->center_freq),
1912 		      wiphy_name(wiphy));
1913 
1914 	memcpy(&reg_beacon->chan, beacon_chan,
1915 		sizeof(struct ieee80211_channel));
1916 
1917 
1918 	/*
1919 	 * Since we can be called from BH or and non-BH context
1920 	 * we must use spin_lock_bh()
1921 	 */
1922 	spin_lock_bh(&reg_pending_beacons_lock);
1923 	list_add_tail(&reg_beacon->list, &reg_pending_beacons);
1924 	spin_unlock_bh(&reg_pending_beacons_lock);
1925 
1926 	schedule_work(&reg_work);
1927 
1928 	return 0;
1929 }
1930 
1931 static void print_rd_rules(const struct ieee80211_regdomain *rd)
1932 {
1933 	unsigned int i;
1934 	const struct ieee80211_reg_rule *reg_rule = NULL;
1935 	const struct ieee80211_freq_range *freq_range = NULL;
1936 	const struct ieee80211_power_rule *power_rule = NULL;
1937 
1938 	pr_info("    (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)\n");
1939 
1940 	for (i = 0; i < rd->n_reg_rules; i++) {
1941 		reg_rule = &rd->reg_rules[i];
1942 		freq_range = &reg_rule->freq_range;
1943 		power_rule = &reg_rule->power_rule;
1944 
1945 		/*
1946 		 * There may not be documentation for max antenna gain
1947 		 * in certain regions
1948 		 */
1949 		if (power_rule->max_antenna_gain)
1950 			pr_info("    (%d KHz - %d KHz @ %d KHz), (%d mBi, %d mBm)\n",
1951 				freq_range->start_freq_khz,
1952 				freq_range->end_freq_khz,
1953 				freq_range->max_bandwidth_khz,
1954 				power_rule->max_antenna_gain,
1955 				power_rule->max_eirp);
1956 		else
1957 			pr_info("    (%d KHz - %d KHz @ %d KHz), (N/A, %d mBm)\n",
1958 				freq_range->start_freq_khz,
1959 				freq_range->end_freq_khz,
1960 				freq_range->max_bandwidth_khz,
1961 				power_rule->max_eirp);
1962 	}
1963 }
1964 
1965 static void print_regdomain(const struct ieee80211_regdomain *rd)
1966 {
1967 
1968 	if (is_intersected_alpha2(rd->alpha2)) {
1969 
1970 		if (last_request->initiator ==
1971 		    NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1972 			struct cfg80211_registered_device *rdev;
1973 			rdev = cfg80211_rdev_by_wiphy_idx(
1974 				last_request->wiphy_idx);
1975 			if (rdev) {
1976 				pr_info("Current regulatory domain updated by AP to: %c%c\n",
1977 					rdev->country_ie_alpha2[0],
1978 					rdev->country_ie_alpha2[1]);
1979 			} else
1980 				pr_info("Current regulatory domain intersected:\n");
1981 		} else
1982 			pr_info("Current regulatory domain intersected:\n");
1983 	} else if (is_world_regdom(rd->alpha2))
1984 		pr_info("World regulatory domain updated:\n");
1985 	else {
1986 		if (is_unknown_alpha2(rd->alpha2))
1987 			pr_info("Regulatory domain changed to driver built-in settings (unknown country)\n");
1988 		else
1989 			pr_info("Regulatory domain changed to country: %c%c\n",
1990 				rd->alpha2[0], rd->alpha2[1]);
1991 	}
1992 	print_rd_rules(rd);
1993 }
1994 
1995 static void print_regdomain_info(const struct ieee80211_regdomain *rd)
1996 {
1997 	pr_info("Regulatory domain: %c%c\n", rd->alpha2[0], rd->alpha2[1]);
1998 	print_rd_rules(rd);
1999 }
2000 
2001 /* Takes ownership of rd only if it doesn't fail */
2002 static int __set_regdom(const struct ieee80211_regdomain *rd)
2003 {
2004 	const struct ieee80211_regdomain *intersected_rd = NULL;
2005 	struct cfg80211_registered_device *rdev = NULL;
2006 	struct wiphy *request_wiphy;
2007 	/* Some basic sanity checks first */
2008 
2009 	if (is_world_regdom(rd->alpha2)) {
2010 		if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
2011 			return -EINVAL;
2012 		update_world_regdomain(rd);
2013 		return 0;
2014 	}
2015 
2016 	if (!is_alpha2_set(rd->alpha2) && !is_an_alpha2(rd->alpha2) &&
2017 			!is_unknown_alpha2(rd->alpha2))
2018 		return -EINVAL;
2019 
2020 	if (!last_request)
2021 		return -EINVAL;
2022 
2023 	/*
2024 	 * Lets only bother proceeding on the same alpha2 if the current
2025 	 * rd is non static (it means CRDA was present and was used last)
2026 	 * and the pending request came in from a country IE
2027 	 */
2028 	if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2029 		/*
2030 		 * If someone else asked us to change the rd lets only bother
2031 		 * checking if the alpha2 changes if CRDA was already called
2032 		 */
2033 		if (!regdom_changes(rd->alpha2))
2034 			return -EINVAL;
2035 	}
2036 
2037 	/*
2038 	 * Now lets set the regulatory domain, update all driver channels
2039 	 * and finally inform them of what we have done, in case they want
2040 	 * to review or adjust their own settings based on their own
2041 	 * internal EEPROM data
2042 	 */
2043 
2044 	if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
2045 		return -EINVAL;
2046 
2047 	if (!is_valid_rd(rd)) {
2048 		pr_err("Invalid regulatory domain detected:\n");
2049 		print_regdomain_info(rd);
2050 		return -EINVAL;
2051 	}
2052 
2053 	request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
2054 	if (!request_wiphy &&
2055 	    (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER ||
2056 	     last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE)) {
2057 		schedule_delayed_work(&reg_timeout, 0);
2058 		return -ENODEV;
2059 	}
2060 
2061 	if (!last_request->intersect) {
2062 		int r;
2063 
2064 		if (last_request->initiator != NL80211_REGDOM_SET_BY_DRIVER) {
2065 			reset_regdomains(false);
2066 			cfg80211_regdomain = rd;
2067 			return 0;
2068 		}
2069 
2070 		/*
2071 		 * For a driver hint, lets copy the regulatory domain the
2072 		 * driver wanted to the wiphy to deal with conflicts
2073 		 */
2074 
2075 		/*
2076 		 * Userspace could have sent two replies with only
2077 		 * one kernel request.
2078 		 */
2079 		if (request_wiphy->regd)
2080 			return -EALREADY;
2081 
2082 		r = reg_copy_regd(&request_wiphy->regd, rd);
2083 		if (r)
2084 			return r;
2085 
2086 		reset_regdomains(false);
2087 		cfg80211_regdomain = rd;
2088 		return 0;
2089 	}
2090 
2091 	/* Intersection requires a bit more work */
2092 
2093 	if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2094 
2095 		intersected_rd = regdom_intersect(rd, cfg80211_regdomain);
2096 		if (!intersected_rd)
2097 			return -EINVAL;
2098 
2099 		/*
2100 		 * We can trash what CRDA provided now.
2101 		 * However if a driver requested this specific regulatory
2102 		 * domain we keep it for its private use
2103 		 */
2104 		if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER)
2105 			request_wiphy->regd = rd;
2106 		else
2107 			kfree(rd);
2108 
2109 		rd = NULL;
2110 
2111 		reset_regdomains(false);
2112 		cfg80211_regdomain = intersected_rd;
2113 
2114 		return 0;
2115 	}
2116 
2117 	if (!intersected_rd)
2118 		return -EINVAL;
2119 
2120 	rdev = wiphy_to_dev(request_wiphy);
2121 
2122 	rdev->country_ie_alpha2[0] = rd->alpha2[0];
2123 	rdev->country_ie_alpha2[1] = rd->alpha2[1];
2124 	rdev->env = last_request->country_ie_env;
2125 
2126 	BUG_ON(intersected_rd == rd);
2127 
2128 	kfree(rd);
2129 	rd = NULL;
2130 
2131 	reset_regdomains(false);
2132 	cfg80211_regdomain = intersected_rd;
2133 
2134 	return 0;
2135 }
2136 
2137 
2138 /*
2139  * Use this call to set the current regulatory domain. Conflicts with
2140  * multiple drivers can be ironed out later. Caller must've already
2141  * kmalloc'd the rd structure. Caller must hold cfg80211_mutex
2142  */
2143 int set_regdom(const struct ieee80211_regdomain *rd)
2144 {
2145 	int r;
2146 
2147 	assert_cfg80211_lock();
2148 
2149 	mutex_lock(&reg_mutex);
2150 
2151 	/* Note that this doesn't update the wiphys, this is done below */
2152 	r = __set_regdom(rd);
2153 	if (r) {
2154 		kfree(rd);
2155 		mutex_unlock(&reg_mutex);
2156 		return r;
2157 	}
2158 
2159 	/* This would make this whole thing pointless */
2160 	if (!last_request->intersect)
2161 		BUG_ON(rd != cfg80211_regdomain);
2162 
2163 	/* update all wiphys now with the new established regulatory domain */
2164 	update_all_wiphy_regulatory(last_request->initiator);
2165 
2166 	print_regdomain(cfg80211_regdomain);
2167 
2168 	nl80211_send_reg_change_event(last_request);
2169 
2170 	reg_set_request_processed();
2171 
2172 	mutex_unlock(&reg_mutex);
2173 
2174 	return r;
2175 }
2176 
2177 #ifdef CONFIG_HOTPLUG
2178 int reg_device_uevent(struct device *dev, struct kobj_uevent_env *env)
2179 {
2180 	if (last_request && !last_request->processed) {
2181 		if (add_uevent_var(env, "COUNTRY=%c%c",
2182 				   last_request->alpha2[0],
2183 				   last_request->alpha2[1]))
2184 			return -ENOMEM;
2185 	}
2186 
2187 	return 0;
2188 }
2189 #else
2190 int reg_device_uevent(struct device *dev, struct kobj_uevent_env *env)
2191 {
2192 	return -ENODEV;
2193 }
2194 #endif /* CONFIG_HOTPLUG */
2195 
2196 /* Caller must hold cfg80211_mutex */
2197 void reg_device_remove(struct wiphy *wiphy)
2198 {
2199 	struct wiphy *request_wiphy = NULL;
2200 
2201 	assert_cfg80211_lock();
2202 
2203 	mutex_lock(&reg_mutex);
2204 
2205 	kfree(wiphy->regd);
2206 
2207 	if (last_request)
2208 		request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
2209 
2210 	if (!request_wiphy || request_wiphy != wiphy)
2211 		goto out;
2212 
2213 	last_request->wiphy_idx = WIPHY_IDX_STALE;
2214 	last_request->country_ie_env = ENVIRON_ANY;
2215 out:
2216 	mutex_unlock(&reg_mutex);
2217 }
2218 
2219 static void reg_timeout_work(struct work_struct *work)
2220 {
2221 	REG_DBG_PRINT("Timeout while waiting for CRDA to reply, "
2222 		      "restoring regulatory settings\n");
2223 	restore_regulatory_settings(true);
2224 }
2225 
2226 int __init regulatory_init(void)
2227 {
2228 	int err = 0;
2229 
2230 	reg_pdev = platform_device_register_simple("regulatory", 0, NULL, 0);
2231 	if (IS_ERR(reg_pdev))
2232 		return PTR_ERR(reg_pdev);
2233 
2234 	reg_pdev->dev.type = &reg_device_type;
2235 
2236 	spin_lock_init(&reg_requests_lock);
2237 	spin_lock_init(&reg_pending_beacons_lock);
2238 
2239 	cfg80211_regdomain = cfg80211_world_regdom;
2240 
2241 	user_alpha2[0] = '9';
2242 	user_alpha2[1] = '7';
2243 
2244 	/* We always try to get an update for the static regdomain */
2245 	err = regulatory_hint_core(cfg80211_regdomain->alpha2);
2246 	if (err) {
2247 		if (err == -ENOMEM)
2248 			return err;
2249 		/*
2250 		 * N.B. kobject_uevent_env() can fail mainly for when we're out
2251 		 * memory which is handled and propagated appropriately above
2252 		 * but it can also fail during a netlink_broadcast() or during
2253 		 * early boot for call_usermodehelper(). For now treat these
2254 		 * errors as non-fatal.
2255 		 */
2256 		pr_err("kobject_uevent_env() was unable to call CRDA during init\n");
2257 #ifdef CONFIG_CFG80211_REG_DEBUG
2258 		/* We want to find out exactly why when debugging */
2259 		WARN_ON(err);
2260 #endif
2261 	}
2262 
2263 	/*
2264 	 * Finally, if the user set the module parameter treat it
2265 	 * as a user hint.
2266 	 */
2267 	if (!is_world_regdom(ieee80211_regdom))
2268 		regulatory_hint_user(ieee80211_regdom);
2269 
2270 	return 0;
2271 }
2272 
2273 void /* __init_or_exit */ regulatory_exit(void)
2274 {
2275 	struct regulatory_request *reg_request, *tmp;
2276 	struct reg_beacon *reg_beacon, *btmp;
2277 
2278 	cancel_work_sync(&reg_work);
2279 	cancel_delayed_work_sync(&reg_timeout);
2280 
2281 	mutex_lock(&cfg80211_mutex);
2282 	mutex_lock(&reg_mutex);
2283 
2284 	reset_regdomains(true);
2285 
2286 	dev_set_uevent_suppress(&reg_pdev->dev, true);
2287 
2288 	platform_device_unregister(reg_pdev);
2289 
2290 	spin_lock_bh(&reg_pending_beacons_lock);
2291 	if (!list_empty(&reg_pending_beacons)) {
2292 		list_for_each_entry_safe(reg_beacon, btmp,
2293 					 &reg_pending_beacons, list) {
2294 			list_del(&reg_beacon->list);
2295 			kfree(reg_beacon);
2296 		}
2297 	}
2298 	spin_unlock_bh(&reg_pending_beacons_lock);
2299 
2300 	if (!list_empty(&reg_beacon_list)) {
2301 		list_for_each_entry_safe(reg_beacon, btmp,
2302 					 &reg_beacon_list, list) {
2303 			list_del(&reg_beacon->list);
2304 			kfree(reg_beacon);
2305 		}
2306 	}
2307 
2308 	spin_lock(&reg_requests_lock);
2309 	if (!list_empty(&reg_requests_list)) {
2310 		list_for_each_entry_safe(reg_request, tmp,
2311 					 &reg_requests_list, list) {
2312 			list_del(&reg_request->list);
2313 			kfree(reg_request);
2314 		}
2315 	}
2316 	spin_unlock(&reg_requests_lock);
2317 
2318 	mutex_unlock(&reg_mutex);
2319 	mutex_unlock(&cfg80211_mutex);
2320 }
2321