xref: /linux/net/wireless/reg.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
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 2008-2011	Luis R. Rodriguez <mcgrof@qca.qualcomm.com>
6  *
7  * Permission to use, copy, modify, and/or distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 
21 /**
22  * DOC: Wireless regulatory infrastructure
23  *
24  * The usual implementation is for a driver to read a device EEPROM to
25  * determine which regulatory domain it should be operating under, then
26  * looking up the allowable channels in a driver-local table and finally
27  * registering those channels in the wiphy structure.
28  *
29  * Another set of compliance enforcement is for drivers to use their
30  * own compliance limits which can be stored on the EEPROM. The host
31  * driver or firmware may ensure these are used.
32  *
33  * In addition to all this we provide an extra layer of regulatory
34  * conformance. For drivers which do not have any regulatory
35  * information CRDA provides the complete regulatory solution.
36  * For others it provides a community effort on further restrictions
37  * to enhance compliance.
38  *
39  * Note: When number of rules --> infinity we will not be able to
40  * index on alpha2 any more, instead we'll probably have to
41  * rely on some SHA1 checksum of the regdomain for example.
42  *
43  */
44 
45 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
46 
47 #include <linux/kernel.h>
48 #include <linux/export.h>
49 #include <linux/slab.h>
50 #include <linux/list.h>
51 #include <linux/random.h>
52 #include <linux/ctype.h>
53 #include <linux/nl80211.h>
54 #include <linux/platform_device.h>
55 #include <linux/moduleparam.h>
56 #include <net/cfg80211.h>
57 #include "core.h"
58 #include "reg.h"
59 #include "regdb.h"
60 #include "nl80211.h"
61 
62 #ifdef CONFIG_CFG80211_REG_DEBUG
63 #define REG_DBG_PRINT(format, args...)			\
64 	printk(KERN_DEBUG pr_fmt(format), ##args)
65 #else
66 #define REG_DBG_PRINT(args...)
67 #endif
68 
69 static struct regulatory_request core_request_world = {
70 	.initiator = NL80211_REGDOM_SET_BY_CORE,
71 	.alpha2[0] = '0',
72 	.alpha2[1] = '0',
73 	.intersect = false,
74 	.processed = true,
75 	.country_ie_env = ENVIRON_ANY,
76 };
77 
78 /* Receipt of information from last regulatory request */
79 static struct regulatory_request *last_request = &core_request_world;
80 
81 /* To trigger userspace events */
82 static struct platform_device *reg_pdev;
83 
84 static struct device_type reg_device_type = {
85 	.uevent = reg_device_uevent,
86 };
87 
88 /*
89  * Central wireless core regulatory domains, we only need two,
90  * the current one and a world regulatory domain in case we have no
91  * information to give us an alpha2
92  */
93 const struct ieee80211_regdomain *cfg80211_regdomain;
94 
95 /*
96  * Protects static reg.c components:
97  *     - cfg80211_world_regdom
98  *     - cfg80211_regdom
99  *     - last_request
100  *     - reg_num_devs_support_basehint
101  */
102 static DEFINE_MUTEX(reg_mutex);
103 
104 /*
105  * Number of devices that registered to the core
106  * that support cellular base station regulatory hints
107  */
108 static int reg_num_devs_support_basehint;
109 
110 static inline void assert_reg_lock(void)
111 {
112 	lockdep_assert_held(&reg_mutex);
113 }
114 
115 /* Used to queue up regulatory hints */
116 static LIST_HEAD(reg_requests_list);
117 static spinlock_t reg_requests_lock;
118 
119 /* Used to queue up beacon hints for review */
120 static LIST_HEAD(reg_pending_beacons);
121 static spinlock_t reg_pending_beacons_lock;
122 
123 /* Used to keep track of processed beacon hints */
124 static LIST_HEAD(reg_beacon_list);
125 
126 struct reg_beacon {
127 	struct list_head list;
128 	struct ieee80211_channel chan;
129 };
130 
131 static void reg_todo(struct work_struct *work);
132 static DECLARE_WORK(reg_work, reg_todo);
133 
134 static void reg_timeout_work(struct work_struct *work);
135 static DECLARE_DELAYED_WORK(reg_timeout, reg_timeout_work);
136 
137 /* We keep a static world regulatory domain in case of the absence of CRDA */
138 static const struct ieee80211_regdomain world_regdom = {
139 	.n_reg_rules = 6,
140 	.alpha2 =  "00",
141 	.reg_rules = {
142 		/* IEEE 802.11b/g, channels 1..11 */
143 		REG_RULE(2412-10, 2462+10, 40, 6, 20, 0),
144 		/* IEEE 802.11b/g, channels 12..13. */
145 		REG_RULE(2467-10, 2472+10, 40, 6, 20,
146 			NL80211_RRF_PASSIVE_SCAN |
147 			NL80211_RRF_NO_IBSS),
148 		/* IEEE 802.11 channel 14 - Only JP enables
149 		 * this and for 802.11b only */
150 		REG_RULE(2484-10, 2484+10, 20, 6, 20,
151 			NL80211_RRF_PASSIVE_SCAN |
152 			NL80211_RRF_NO_IBSS |
153 			NL80211_RRF_NO_OFDM),
154 		/* IEEE 802.11a, channel 36..48 */
155 		REG_RULE(5180-10, 5240+10, 40, 6, 20,
156                         NL80211_RRF_PASSIVE_SCAN |
157                         NL80211_RRF_NO_IBSS),
158 
159 		/* NB: 5260 MHz - 5700 MHz requies DFS */
160 
161 		/* IEEE 802.11a, channel 149..165 */
162 		REG_RULE(5745-10, 5825+10, 40, 6, 20,
163 			NL80211_RRF_PASSIVE_SCAN |
164 			NL80211_RRF_NO_IBSS),
165 
166 		/* IEEE 802.11ad (60gHz), channels 1..3 */
167 		REG_RULE(56160+2160*1-1080, 56160+2160*3+1080, 2160, 0, 0, 0),
168 	}
169 };
170 
171 static const struct ieee80211_regdomain *cfg80211_world_regdom =
172 	&world_regdom;
173 
174 static char *ieee80211_regdom = "00";
175 static char user_alpha2[2];
176 
177 module_param(ieee80211_regdom, charp, 0444);
178 MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain code");
179 
180 static void reset_regdomains(bool full_reset)
181 {
182 	/* avoid freeing static information or freeing something twice */
183 	if (cfg80211_regdomain == cfg80211_world_regdom)
184 		cfg80211_regdomain = NULL;
185 	if (cfg80211_world_regdom == &world_regdom)
186 		cfg80211_world_regdom = NULL;
187 	if (cfg80211_regdomain == &world_regdom)
188 		cfg80211_regdomain = NULL;
189 
190 	kfree(cfg80211_regdomain);
191 	kfree(cfg80211_world_regdom);
192 
193 	cfg80211_world_regdom = &world_regdom;
194 	cfg80211_regdomain = NULL;
195 
196 	if (!full_reset)
197 		return;
198 
199 	if (last_request != &core_request_world)
200 		kfree(last_request);
201 	last_request = &core_request_world;
202 }
203 
204 /*
205  * Dynamic world regulatory domain requested by the wireless
206  * core upon initialization
207  */
208 static void update_world_regdomain(const struct ieee80211_regdomain *rd)
209 {
210 	BUG_ON(!last_request);
211 
212 	reset_regdomains(false);
213 
214 	cfg80211_world_regdom = rd;
215 	cfg80211_regdomain = rd;
216 }
217 
218 bool is_world_regdom(const char *alpha2)
219 {
220 	if (!alpha2)
221 		return false;
222 	if (alpha2[0] == '0' && alpha2[1] == '0')
223 		return true;
224 	return false;
225 }
226 
227 static bool is_alpha2_set(const char *alpha2)
228 {
229 	if (!alpha2)
230 		return false;
231 	if (alpha2[0] != 0 && alpha2[1] != 0)
232 		return true;
233 	return false;
234 }
235 
236 static bool is_unknown_alpha2(const char *alpha2)
237 {
238 	if (!alpha2)
239 		return false;
240 	/*
241 	 * Special case where regulatory domain was built by driver
242 	 * but a specific alpha2 cannot be determined
243 	 */
244 	if (alpha2[0] == '9' && alpha2[1] == '9')
245 		return true;
246 	return false;
247 }
248 
249 static bool is_intersected_alpha2(const char *alpha2)
250 {
251 	if (!alpha2)
252 		return false;
253 	/*
254 	 * Special case where regulatory domain is the
255 	 * result of an intersection between two regulatory domain
256 	 * structures
257 	 */
258 	if (alpha2[0] == '9' && alpha2[1] == '8')
259 		return true;
260 	return false;
261 }
262 
263 static bool is_an_alpha2(const char *alpha2)
264 {
265 	if (!alpha2)
266 		return false;
267 	if (isalpha(alpha2[0]) && isalpha(alpha2[1]))
268 		return true;
269 	return false;
270 }
271 
272 static bool alpha2_equal(const char *alpha2_x, const char *alpha2_y)
273 {
274 	if (!alpha2_x || !alpha2_y)
275 		return false;
276 	if (alpha2_x[0] == alpha2_y[0] &&
277 		alpha2_x[1] == alpha2_y[1])
278 		return true;
279 	return false;
280 }
281 
282 static bool regdom_changes(const char *alpha2)
283 {
284 	assert_cfg80211_lock();
285 
286 	if (!cfg80211_regdomain)
287 		return true;
288 	if (alpha2_equal(cfg80211_regdomain->alpha2, alpha2))
289 		return false;
290 	return true;
291 }
292 
293 /*
294  * The NL80211_REGDOM_SET_BY_USER regdom alpha2 is cached, this lets
295  * you know if a valid regulatory hint with NL80211_REGDOM_SET_BY_USER
296  * has ever been issued.
297  */
298 static bool is_user_regdom_saved(void)
299 {
300 	if (user_alpha2[0] == '9' && user_alpha2[1] == '7')
301 		return false;
302 
303 	/* This would indicate a mistake on the design */
304 	if (WARN((!is_world_regdom(user_alpha2) &&
305 		  !is_an_alpha2(user_alpha2)),
306 		 "Unexpected user alpha2: %c%c\n",
307 		 user_alpha2[0],
308 	         user_alpha2[1]))
309 		return false;
310 
311 	return true;
312 }
313 
314 static int reg_copy_regd(const struct ieee80211_regdomain **dst_regd,
315 			 const struct ieee80211_regdomain *src_regd)
316 {
317 	struct ieee80211_regdomain *regd;
318 	int size_of_regd = 0;
319 	unsigned int i;
320 
321 	size_of_regd = sizeof(struct ieee80211_regdomain) +
322 	  ((src_regd->n_reg_rules + 1) * sizeof(struct ieee80211_reg_rule));
323 
324 	regd = kzalloc(size_of_regd, GFP_KERNEL);
325 	if (!regd)
326 		return -ENOMEM;
327 
328 	memcpy(regd, src_regd, sizeof(struct ieee80211_regdomain));
329 
330 	for (i = 0; i < src_regd->n_reg_rules; i++)
331 		memcpy(&regd->reg_rules[i], &src_regd->reg_rules[i],
332 			sizeof(struct ieee80211_reg_rule));
333 
334 	*dst_regd = regd;
335 	return 0;
336 }
337 
338 #ifdef CONFIG_CFG80211_INTERNAL_REGDB
339 struct reg_regdb_search_request {
340 	char alpha2[2];
341 	struct list_head list;
342 };
343 
344 static LIST_HEAD(reg_regdb_search_list);
345 static DEFINE_MUTEX(reg_regdb_search_mutex);
346 
347 static void reg_regdb_search(struct work_struct *work)
348 {
349 	struct reg_regdb_search_request *request;
350 	const struct ieee80211_regdomain *curdom, *regdom;
351 	int i, r;
352 	bool set_reg = false;
353 
354 	mutex_lock(&cfg80211_mutex);
355 
356 	mutex_lock(&reg_regdb_search_mutex);
357 	while (!list_empty(&reg_regdb_search_list)) {
358 		request = list_first_entry(&reg_regdb_search_list,
359 					   struct reg_regdb_search_request,
360 					   list);
361 		list_del(&request->list);
362 
363 		for (i=0; i<reg_regdb_size; i++) {
364 			curdom = reg_regdb[i];
365 
366 			if (!memcmp(request->alpha2, curdom->alpha2, 2)) {
367 				r = reg_copy_regd(&regdom, curdom);
368 				if (r)
369 					break;
370 				set_reg = true;
371 				break;
372 			}
373 		}
374 
375 		kfree(request);
376 	}
377 	mutex_unlock(&reg_regdb_search_mutex);
378 
379 	if (set_reg)
380 		set_regdom(regdom);
381 
382 	mutex_unlock(&cfg80211_mutex);
383 }
384 
385 static DECLARE_WORK(reg_regdb_work, reg_regdb_search);
386 
387 static void reg_regdb_query(const char *alpha2)
388 {
389 	struct reg_regdb_search_request *request;
390 
391 	if (!alpha2)
392 		return;
393 
394 	request = kzalloc(sizeof(struct reg_regdb_search_request), GFP_KERNEL);
395 	if (!request)
396 		return;
397 
398 	memcpy(request->alpha2, alpha2, 2);
399 
400 	mutex_lock(&reg_regdb_search_mutex);
401 	list_add_tail(&request->list, &reg_regdb_search_list);
402 	mutex_unlock(&reg_regdb_search_mutex);
403 
404 	schedule_work(&reg_regdb_work);
405 }
406 
407 /* Feel free to add any other sanity checks here */
408 static void reg_regdb_size_check(void)
409 {
410 	/* We should ideally BUILD_BUG_ON() but then random builds would fail */
411 	WARN_ONCE(!reg_regdb_size, "db.txt is empty, you should update it...");
412 }
413 #else
414 static inline void reg_regdb_size_check(void) {}
415 static inline void reg_regdb_query(const char *alpha2) {}
416 #endif /* CONFIG_CFG80211_INTERNAL_REGDB */
417 
418 /*
419  * This lets us keep regulatory code which is updated on a regulatory
420  * basis in userspace. Country information is filled in by
421  * reg_device_uevent
422  */
423 static int call_crda(const char *alpha2)
424 {
425 	if (!is_world_regdom((char *) alpha2))
426 		pr_info("Calling CRDA for country: %c%c\n",
427 			alpha2[0], alpha2[1]);
428 	else
429 		pr_info("Calling CRDA to update world regulatory domain\n");
430 
431 	/* query internal regulatory database (if it exists) */
432 	reg_regdb_query(alpha2);
433 
434 	return kobject_uevent(&reg_pdev->dev.kobj, KOBJ_CHANGE);
435 }
436 
437 /* Used by nl80211 before kmalloc'ing our regulatory domain */
438 bool reg_is_valid_request(const char *alpha2)
439 {
440 	assert_cfg80211_lock();
441 
442 	if (!last_request)
443 		return false;
444 
445 	return alpha2_equal(last_request->alpha2, alpha2);
446 }
447 
448 /* Sanity check on a regulatory rule */
449 static bool is_valid_reg_rule(const struct ieee80211_reg_rule *rule)
450 {
451 	const struct ieee80211_freq_range *freq_range = &rule->freq_range;
452 	u32 freq_diff;
453 
454 	if (freq_range->start_freq_khz <= 0 || freq_range->end_freq_khz <= 0)
455 		return false;
456 
457 	if (freq_range->start_freq_khz > freq_range->end_freq_khz)
458 		return false;
459 
460 	freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
461 
462 	if (freq_range->end_freq_khz <= freq_range->start_freq_khz ||
463 			freq_range->max_bandwidth_khz > freq_diff)
464 		return false;
465 
466 	return true;
467 }
468 
469 static bool is_valid_rd(const struct ieee80211_regdomain *rd)
470 {
471 	const struct ieee80211_reg_rule *reg_rule = NULL;
472 	unsigned int i;
473 
474 	if (!rd->n_reg_rules)
475 		return false;
476 
477 	if (WARN_ON(rd->n_reg_rules > NL80211_MAX_SUPP_REG_RULES))
478 		return false;
479 
480 	for (i = 0; i < rd->n_reg_rules; i++) {
481 		reg_rule = &rd->reg_rules[i];
482 		if (!is_valid_reg_rule(reg_rule))
483 			return false;
484 	}
485 
486 	return true;
487 }
488 
489 static bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_range,
490 			    u32 center_freq_khz,
491 			    u32 bw_khz)
492 {
493 	u32 start_freq_khz, end_freq_khz;
494 
495 	start_freq_khz = center_freq_khz - (bw_khz/2);
496 	end_freq_khz = center_freq_khz + (bw_khz/2);
497 
498 	if (start_freq_khz >= freq_range->start_freq_khz &&
499 	    end_freq_khz <= freq_range->end_freq_khz)
500 		return true;
501 
502 	return false;
503 }
504 
505 /**
506  * freq_in_rule_band - tells us if a frequency is in a frequency band
507  * @freq_range: frequency rule we want to query
508  * @freq_khz: frequency we are inquiring about
509  *
510  * This lets us know if a specific frequency rule is or is not relevant to
511  * a specific frequency's band. Bands are device specific and artificial
512  * definitions (the "2.4 GHz band", the "5 GHz band" and the "60GHz band"),
513  * however it is safe for now to assume that a frequency rule should not be
514  * part of a frequency's band if the start freq or end freq are off by more
515  * than 2 GHz for the 2.4 and 5 GHz bands, and by more than 10 GHz for the
516  * 60 GHz band.
517  * This resolution can be lowered and should be considered as we add
518  * regulatory rule support for other "bands".
519  **/
520 static bool freq_in_rule_band(const struct ieee80211_freq_range *freq_range,
521 	u32 freq_khz)
522 {
523 #define ONE_GHZ_IN_KHZ	1000000
524 	/*
525 	 * From 802.11ad: directional multi-gigabit (DMG):
526 	 * Pertaining to operation in a frequency band containing a channel
527 	 * with the Channel starting frequency above 45 GHz.
528 	 */
529 	u32 limit = freq_khz > 45 * ONE_GHZ_IN_KHZ ?
530 			10 * ONE_GHZ_IN_KHZ : 2 * ONE_GHZ_IN_KHZ;
531 	if (abs(freq_khz - freq_range->start_freq_khz) <= limit)
532 		return true;
533 	if (abs(freq_khz - freq_range->end_freq_khz) <= limit)
534 		return true;
535 	return false;
536 #undef ONE_GHZ_IN_KHZ
537 }
538 
539 /*
540  * Helper for regdom_intersect(), this does the real
541  * mathematical intersection fun
542  */
543 static int reg_rules_intersect(
544 	const struct ieee80211_reg_rule *rule1,
545 	const struct ieee80211_reg_rule *rule2,
546 	struct ieee80211_reg_rule *intersected_rule)
547 {
548 	const struct ieee80211_freq_range *freq_range1, *freq_range2;
549 	struct ieee80211_freq_range *freq_range;
550 	const struct ieee80211_power_rule *power_rule1, *power_rule2;
551 	struct ieee80211_power_rule *power_rule;
552 	u32 freq_diff;
553 
554 	freq_range1 = &rule1->freq_range;
555 	freq_range2 = &rule2->freq_range;
556 	freq_range = &intersected_rule->freq_range;
557 
558 	power_rule1 = &rule1->power_rule;
559 	power_rule2 = &rule2->power_rule;
560 	power_rule = &intersected_rule->power_rule;
561 
562 	freq_range->start_freq_khz = max(freq_range1->start_freq_khz,
563 		freq_range2->start_freq_khz);
564 	freq_range->end_freq_khz = min(freq_range1->end_freq_khz,
565 		freq_range2->end_freq_khz);
566 	freq_range->max_bandwidth_khz = min(freq_range1->max_bandwidth_khz,
567 		freq_range2->max_bandwidth_khz);
568 
569 	freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
570 	if (freq_range->max_bandwidth_khz > freq_diff)
571 		freq_range->max_bandwidth_khz = freq_diff;
572 
573 	power_rule->max_eirp = min(power_rule1->max_eirp,
574 		power_rule2->max_eirp);
575 	power_rule->max_antenna_gain = min(power_rule1->max_antenna_gain,
576 		power_rule2->max_antenna_gain);
577 
578 	intersected_rule->flags = (rule1->flags | rule2->flags);
579 
580 	if (!is_valid_reg_rule(intersected_rule))
581 		return -EINVAL;
582 
583 	return 0;
584 }
585 
586 /**
587  * regdom_intersect - do the intersection between two regulatory domains
588  * @rd1: first regulatory domain
589  * @rd2: second regulatory domain
590  *
591  * Use this function to get the intersection between two regulatory domains.
592  * Once completed we will mark the alpha2 for the rd as intersected, "98",
593  * as no one single alpha2 can represent this regulatory domain.
594  *
595  * Returns a pointer to the regulatory domain structure which will hold the
596  * resulting intersection of rules between rd1 and rd2. We will
597  * kzalloc() this structure for you.
598  */
599 static struct ieee80211_regdomain *regdom_intersect(
600 	const struct ieee80211_regdomain *rd1,
601 	const struct ieee80211_regdomain *rd2)
602 {
603 	int r, size_of_regd;
604 	unsigned int x, y;
605 	unsigned int num_rules = 0, rule_idx = 0;
606 	const struct ieee80211_reg_rule *rule1, *rule2;
607 	struct ieee80211_reg_rule *intersected_rule;
608 	struct ieee80211_regdomain *rd;
609 	/* This is just a dummy holder to help us count */
610 	struct ieee80211_reg_rule irule;
611 
612 	/* Uses the stack temporarily for counter arithmetic */
613 	intersected_rule = &irule;
614 
615 	memset(intersected_rule, 0, sizeof(struct ieee80211_reg_rule));
616 
617 	if (!rd1 || !rd2)
618 		return NULL;
619 
620 	/*
621 	 * First we get a count of the rules we'll need, then we actually
622 	 * build them. This is to so we can malloc() and free() a
623 	 * regdomain once. The reason we use reg_rules_intersect() here
624 	 * is it will return -EINVAL if the rule computed makes no sense.
625 	 * All rules that do check out OK are valid.
626 	 */
627 
628 	for (x = 0; x < rd1->n_reg_rules; x++) {
629 		rule1 = &rd1->reg_rules[x];
630 		for (y = 0; y < rd2->n_reg_rules; y++) {
631 			rule2 = &rd2->reg_rules[y];
632 			if (!reg_rules_intersect(rule1, rule2,
633 					intersected_rule))
634 				num_rules++;
635 			memset(intersected_rule, 0,
636 					sizeof(struct ieee80211_reg_rule));
637 		}
638 	}
639 
640 	if (!num_rules)
641 		return NULL;
642 
643 	size_of_regd = sizeof(struct ieee80211_regdomain) +
644 		((num_rules + 1) * sizeof(struct ieee80211_reg_rule));
645 
646 	rd = kzalloc(size_of_regd, GFP_KERNEL);
647 	if (!rd)
648 		return NULL;
649 
650 	for (x = 0; x < rd1->n_reg_rules; x++) {
651 		rule1 = &rd1->reg_rules[x];
652 		for (y = 0; y < rd2->n_reg_rules; y++) {
653 			rule2 = &rd2->reg_rules[y];
654 			/*
655 			 * This time around instead of using the stack lets
656 			 * write to the target rule directly saving ourselves
657 			 * a memcpy()
658 			 */
659 			intersected_rule = &rd->reg_rules[rule_idx];
660 			r = reg_rules_intersect(rule1, rule2,
661 				intersected_rule);
662 			/*
663 			 * No need to memset here the intersected rule here as
664 			 * we're not using the stack anymore
665 			 */
666 			if (r)
667 				continue;
668 			rule_idx++;
669 		}
670 	}
671 
672 	if (rule_idx != num_rules) {
673 		kfree(rd);
674 		return NULL;
675 	}
676 
677 	rd->n_reg_rules = num_rules;
678 	rd->alpha2[0] = '9';
679 	rd->alpha2[1] = '8';
680 
681 	return rd;
682 }
683 
684 /*
685  * XXX: add support for the rest of enum nl80211_reg_rule_flags, we may
686  * want to just have the channel structure use these
687  */
688 static u32 map_regdom_flags(u32 rd_flags)
689 {
690 	u32 channel_flags = 0;
691 	if (rd_flags & NL80211_RRF_PASSIVE_SCAN)
692 		channel_flags |= IEEE80211_CHAN_PASSIVE_SCAN;
693 	if (rd_flags & NL80211_RRF_NO_IBSS)
694 		channel_flags |= IEEE80211_CHAN_NO_IBSS;
695 	if (rd_flags & NL80211_RRF_DFS)
696 		channel_flags |= IEEE80211_CHAN_RADAR;
697 	if (rd_flags & NL80211_RRF_NO_OFDM)
698 		channel_flags |= IEEE80211_CHAN_NO_OFDM;
699 	return channel_flags;
700 }
701 
702 static int freq_reg_info_regd(struct wiphy *wiphy,
703 			      u32 center_freq,
704 			      u32 desired_bw_khz,
705 			      const struct ieee80211_reg_rule **reg_rule,
706 			      const struct ieee80211_regdomain *custom_regd)
707 {
708 	int i;
709 	bool band_rule_found = false;
710 	const struct ieee80211_regdomain *regd;
711 	bool bw_fits = false;
712 
713 	if (!desired_bw_khz)
714 		desired_bw_khz = MHZ_TO_KHZ(20);
715 
716 	regd = custom_regd ? custom_regd : cfg80211_regdomain;
717 
718 	/*
719 	 * Follow the driver's regulatory domain, if present, unless a country
720 	 * IE has been processed or a user wants to help complaince further
721 	 */
722 	if (!custom_regd &&
723 	    last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
724 	    last_request->initiator != NL80211_REGDOM_SET_BY_USER &&
725 	    wiphy->regd)
726 		regd = wiphy->regd;
727 
728 	if (!regd)
729 		return -EINVAL;
730 
731 	for (i = 0; i < regd->n_reg_rules; i++) {
732 		const struct ieee80211_reg_rule *rr;
733 		const struct ieee80211_freq_range *fr = NULL;
734 
735 		rr = &regd->reg_rules[i];
736 		fr = &rr->freq_range;
737 
738 		/*
739 		 * We only need to know if one frequency rule was
740 		 * was in center_freq's band, that's enough, so lets
741 		 * not overwrite it once found
742 		 */
743 		if (!band_rule_found)
744 			band_rule_found = freq_in_rule_band(fr, center_freq);
745 
746 		bw_fits = reg_does_bw_fit(fr,
747 					  center_freq,
748 					  desired_bw_khz);
749 
750 		if (band_rule_found && bw_fits) {
751 			*reg_rule = rr;
752 			return 0;
753 		}
754 	}
755 
756 	if (!band_rule_found)
757 		return -ERANGE;
758 
759 	return -EINVAL;
760 }
761 
762 int freq_reg_info(struct wiphy *wiphy,
763 		  u32 center_freq,
764 		  u32 desired_bw_khz,
765 		  const struct ieee80211_reg_rule **reg_rule)
766 {
767 	assert_cfg80211_lock();
768 	return freq_reg_info_regd(wiphy,
769 				  center_freq,
770 				  desired_bw_khz,
771 				  reg_rule,
772 				  NULL);
773 }
774 EXPORT_SYMBOL(freq_reg_info);
775 
776 #ifdef CONFIG_CFG80211_REG_DEBUG
777 static const char *reg_initiator_name(enum nl80211_reg_initiator initiator)
778 {
779 	switch (initiator) {
780 	case NL80211_REGDOM_SET_BY_CORE:
781 		return "Set by core";
782 	case NL80211_REGDOM_SET_BY_USER:
783 		return "Set by user";
784 	case NL80211_REGDOM_SET_BY_DRIVER:
785 		return "Set by driver";
786 	case NL80211_REGDOM_SET_BY_COUNTRY_IE:
787 		return "Set by country IE";
788 	default:
789 		WARN_ON(1);
790 		return "Set by bug";
791 	}
792 }
793 
794 static void chan_reg_rule_print_dbg(struct ieee80211_channel *chan,
795 				    u32 desired_bw_khz,
796 				    const struct ieee80211_reg_rule *reg_rule)
797 {
798 	const struct ieee80211_power_rule *power_rule;
799 	const struct ieee80211_freq_range *freq_range;
800 	char max_antenna_gain[32];
801 
802 	power_rule = &reg_rule->power_rule;
803 	freq_range = &reg_rule->freq_range;
804 
805 	if (!power_rule->max_antenna_gain)
806 		snprintf(max_antenna_gain, 32, "N/A");
807 	else
808 		snprintf(max_antenna_gain, 32, "%d", power_rule->max_antenna_gain);
809 
810 	REG_DBG_PRINT("Updating information on frequency %d MHz "
811 		      "for a %d MHz width channel with regulatory rule:\n",
812 		      chan->center_freq,
813 		      KHZ_TO_MHZ(desired_bw_khz));
814 
815 	REG_DBG_PRINT("%d KHz - %d KHz @ %d KHz), (%s mBi, %d mBm)\n",
816 		      freq_range->start_freq_khz,
817 		      freq_range->end_freq_khz,
818 		      freq_range->max_bandwidth_khz,
819 		      max_antenna_gain,
820 		      power_rule->max_eirp);
821 }
822 #else
823 static void chan_reg_rule_print_dbg(struct ieee80211_channel *chan,
824 				    u32 desired_bw_khz,
825 				    const struct ieee80211_reg_rule *reg_rule)
826 {
827 	return;
828 }
829 #endif
830 
831 /*
832  * Note that right now we assume the desired channel bandwidth
833  * is always 20 MHz for each individual channel (HT40 uses 20 MHz
834  * per channel, the primary and the extension channel). To support
835  * smaller custom bandwidths such as 5 MHz or 10 MHz we'll need a
836  * new ieee80211_channel.target_bw and re run the regulatory check
837  * on the wiphy with the target_bw specified. Then we can simply use
838  * that below for the desired_bw_khz below.
839  */
840 static void handle_channel(struct wiphy *wiphy,
841 			   enum nl80211_reg_initiator initiator,
842 			   enum ieee80211_band band,
843 			   unsigned int chan_idx)
844 {
845 	int r;
846 	u32 flags, bw_flags = 0;
847 	u32 desired_bw_khz = MHZ_TO_KHZ(20);
848 	const struct ieee80211_reg_rule *reg_rule = NULL;
849 	const struct ieee80211_power_rule *power_rule = NULL;
850 	const struct ieee80211_freq_range *freq_range = NULL;
851 	struct ieee80211_supported_band *sband;
852 	struct ieee80211_channel *chan;
853 	struct wiphy *request_wiphy = NULL;
854 
855 	assert_cfg80211_lock();
856 
857 	request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
858 
859 	sband = wiphy->bands[band];
860 	BUG_ON(chan_idx >= sband->n_channels);
861 	chan = &sband->channels[chan_idx];
862 
863 	flags = chan->orig_flags;
864 
865 	r = freq_reg_info(wiphy,
866 			  MHZ_TO_KHZ(chan->center_freq),
867 			  desired_bw_khz,
868 			  &reg_rule);
869 
870 	if (r) {
871 		/*
872 		 * We will disable all channels that do not match our
873 		 * received regulatory rule unless the hint is coming
874 		 * from a Country IE and the Country IE had no information
875 		 * about a band. The IEEE 802.11 spec allows for an AP
876 		 * to send only a subset of the regulatory rules allowed,
877 		 * so an AP in the US that only supports 2.4 GHz may only send
878 		 * a country IE with information for the 2.4 GHz band
879 		 * while 5 GHz is still supported.
880 		 */
881 		if (initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE &&
882 		    r == -ERANGE)
883 			return;
884 
885 		REG_DBG_PRINT("Disabling freq %d MHz\n", chan->center_freq);
886 		chan->flags = IEEE80211_CHAN_DISABLED;
887 		return;
888 	}
889 
890 	chan_reg_rule_print_dbg(chan, desired_bw_khz, reg_rule);
891 
892 	power_rule = &reg_rule->power_rule;
893 	freq_range = &reg_rule->freq_range;
894 
895 	if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
896 		bw_flags = IEEE80211_CHAN_NO_HT40;
897 
898 	if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
899 	    request_wiphy && request_wiphy == wiphy &&
900 	    request_wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY) {
901 		/*
902 		 * This guarantees the driver's requested regulatory domain
903 		 * will always be used as a base for further regulatory
904 		 * settings
905 		 */
906 		chan->flags = chan->orig_flags =
907 			map_regdom_flags(reg_rule->flags) | bw_flags;
908 		chan->max_antenna_gain = chan->orig_mag =
909 			(int) MBI_TO_DBI(power_rule->max_antenna_gain);
910 		chan->max_reg_power = chan->max_power = chan->orig_mpwr =
911 			(int) MBM_TO_DBM(power_rule->max_eirp);
912 		return;
913 	}
914 
915 	chan->beacon_found = false;
916 	chan->flags = flags | bw_flags | map_regdom_flags(reg_rule->flags);
917 	chan->max_antenna_gain = min(chan->orig_mag,
918 		(int) MBI_TO_DBI(power_rule->max_antenna_gain));
919 	chan->max_reg_power = (int) MBM_TO_DBM(power_rule->max_eirp);
920 	if (chan->orig_mpwr) {
921 		/*
922 		 * Devices that have their own custom regulatory domain
923 		 * but also use WIPHY_FLAG_STRICT_REGULATORY will follow the
924 		 * passed country IE power settings.
925 		 */
926 		if (initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE &&
927 		    wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY &&
928 		    wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY)
929 			chan->max_power = chan->max_reg_power;
930 		else
931 			chan->max_power = min(chan->orig_mpwr,
932 					      chan->max_reg_power);
933 	} else
934 		chan->max_power = chan->max_reg_power;
935 }
936 
937 static void handle_band(struct wiphy *wiphy,
938 			enum ieee80211_band band,
939 			enum nl80211_reg_initiator initiator)
940 {
941 	unsigned int i;
942 	struct ieee80211_supported_band *sband;
943 
944 	BUG_ON(!wiphy->bands[band]);
945 	sband = wiphy->bands[band];
946 
947 	for (i = 0; i < sband->n_channels; i++)
948 		handle_channel(wiphy, initiator, band, i);
949 }
950 
951 static bool reg_request_cell_base(struct regulatory_request *request)
952 {
953 	if (request->initiator != NL80211_REGDOM_SET_BY_USER)
954 		return false;
955 	if (request->user_reg_hint_type != NL80211_USER_REG_HINT_CELL_BASE)
956 		return false;
957 	return true;
958 }
959 
960 bool reg_last_request_cell_base(void)
961 {
962 	bool val;
963 	assert_cfg80211_lock();
964 
965 	mutex_lock(&reg_mutex);
966 	val = reg_request_cell_base(last_request);
967 	mutex_unlock(&reg_mutex);
968 	return val;
969 }
970 
971 #ifdef CONFIG_CFG80211_CERTIFICATION_ONUS
972 
973 /* Core specific check */
974 static int reg_ignore_cell_hint(struct regulatory_request *pending_request)
975 {
976 	if (!reg_num_devs_support_basehint)
977 		return -EOPNOTSUPP;
978 
979 	if (reg_request_cell_base(last_request)) {
980 		if (!regdom_changes(pending_request->alpha2))
981 			return -EALREADY;
982 		return 0;
983 	}
984 	return 0;
985 }
986 
987 /* Device specific check */
988 static bool reg_dev_ignore_cell_hint(struct wiphy *wiphy)
989 {
990 	if (!(wiphy->features & NL80211_FEATURE_CELL_BASE_REG_HINTS))
991 		return true;
992 	return false;
993 }
994 #else
995 static int reg_ignore_cell_hint(struct regulatory_request *pending_request)
996 {
997 	return -EOPNOTSUPP;
998 }
999 static int reg_dev_ignore_cell_hint(struct wiphy *wiphy)
1000 {
1001 	return true;
1002 }
1003 #endif
1004 
1005 
1006 static bool ignore_reg_update(struct wiphy *wiphy,
1007 			      enum nl80211_reg_initiator initiator)
1008 {
1009 	if (!last_request) {
1010 		REG_DBG_PRINT("Ignoring regulatory request %s since "
1011 			      "last_request is not set\n",
1012 			      reg_initiator_name(initiator));
1013 		return true;
1014 	}
1015 
1016 	if (initiator == NL80211_REGDOM_SET_BY_CORE &&
1017 	    wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY) {
1018 		REG_DBG_PRINT("Ignoring regulatory request %s "
1019 			      "since the driver uses its own custom "
1020 			      "regulatory domain\n",
1021 			      reg_initiator_name(initiator));
1022 		return true;
1023 	}
1024 
1025 	/*
1026 	 * wiphy->regd will be set once the device has its own
1027 	 * desired regulatory domain set
1028 	 */
1029 	if (wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY && !wiphy->regd &&
1030 	    initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1031 	    !is_world_regdom(last_request->alpha2)) {
1032 		REG_DBG_PRINT("Ignoring regulatory request %s "
1033 			      "since the driver requires its own regulatory "
1034 			      "domain to be set first\n",
1035 			      reg_initiator_name(initiator));
1036 		return true;
1037 	}
1038 
1039 	if (reg_request_cell_base(last_request))
1040 		return reg_dev_ignore_cell_hint(wiphy);
1041 
1042 	return false;
1043 }
1044 
1045 static void handle_reg_beacon(struct wiphy *wiphy,
1046 			      unsigned int chan_idx,
1047 			      struct reg_beacon *reg_beacon)
1048 {
1049 	struct ieee80211_supported_band *sband;
1050 	struct ieee80211_channel *chan;
1051 	bool channel_changed = false;
1052 	struct ieee80211_channel chan_before;
1053 
1054 	assert_cfg80211_lock();
1055 
1056 	sband = wiphy->bands[reg_beacon->chan.band];
1057 	chan = &sband->channels[chan_idx];
1058 
1059 	if (likely(chan->center_freq != reg_beacon->chan.center_freq))
1060 		return;
1061 
1062 	if (chan->beacon_found)
1063 		return;
1064 
1065 	chan->beacon_found = true;
1066 
1067 	if (wiphy->flags & WIPHY_FLAG_DISABLE_BEACON_HINTS)
1068 		return;
1069 
1070 	chan_before.center_freq = chan->center_freq;
1071 	chan_before.flags = chan->flags;
1072 
1073 	if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN) {
1074 		chan->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
1075 		channel_changed = true;
1076 	}
1077 
1078 	if (chan->flags & IEEE80211_CHAN_NO_IBSS) {
1079 		chan->flags &= ~IEEE80211_CHAN_NO_IBSS;
1080 		channel_changed = true;
1081 	}
1082 
1083 	if (channel_changed)
1084 		nl80211_send_beacon_hint_event(wiphy, &chan_before, chan);
1085 }
1086 
1087 /*
1088  * Called when a scan on a wiphy finds a beacon on
1089  * new channel
1090  */
1091 static void wiphy_update_new_beacon(struct wiphy *wiphy,
1092 				    struct reg_beacon *reg_beacon)
1093 {
1094 	unsigned int i;
1095 	struct ieee80211_supported_band *sband;
1096 
1097 	assert_cfg80211_lock();
1098 
1099 	if (!wiphy->bands[reg_beacon->chan.band])
1100 		return;
1101 
1102 	sband = wiphy->bands[reg_beacon->chan.band];
1103 
1104 	for (i = 0; i < sband->n_channels; i++)
1105 		handle_reg_beacon(wiphy, i, reg_beacon);
1106 }
1107 
1108 /*
1109  * Called upon reg changes or a new wiphy is added
1110  */
1111 static void wiphy_update_beacon_reg(struct wiphy *wiphy)
1112 {
1113 	unsigned int i;
1114 	struct ieee80211_supported_band *sband;
1115 	struct reg_beacon *reg_beacon;
1116 
1117 	assert_cfg80211_lock();
1118 
1119 	if (list_empty(&reg_beacon_list))
1120 		return;
1121 
1122 	list_for_each_entry(reg_beacon, &reg_beacon_list, list) {
1123 		if (!wiphy->bands[reg_beacon->chan.band])
1124 			continue;
1125 		sband = wiphy->bands[reg_beacon->chan.band];
1126 		for (i = 0; i < sband->n_channels; i++)
1127 			handle_reg_beacon(wiphy, i, reg_beacon);
1128 	}
1129 }
1130 
1131 static bool reg_is_world_roaming(struct wiphy *wiphy)
1132 {
1133 	if (is_world_regdom(cfg80211_regdomain->alpha2) ||
1134 	    (wiphy->regd && is_world_regdom(wiphy->regd->alpha2)))
1135 		return true;
1136 	if (last_request &&
1137 	    last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1138 	    wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY)
1139 		return true;
1140 	return false;
1141 }
1142 
1143 /* Reap the advantages of previously found beacons */
1144 static void reg_process_beacons(struct wiphy *wiphy)
1145 {
1146 	/*
1147 	 * Means we are just firing up cfg80211, so no beacons would
1148 	 * have been processed yet.
1149 	 */
1150 	if (!last_request)
1151 		return;
1152 	if (!reg_is_world_roaming(wiphy))
1153 		return;
1154 	wiphy_update_beacon_reg(wiphy);
1155 }
1156 
1157 static bool is_ht40_not_allowed(struct ieee80211_channel *chan)
1158 {
1159 	if (!chan)
1160 		return true;
1161 	if (chan->flags & IEEE80211_CHAN_DISABLED)
1162 		return true;
1163 	/* This would happen when regulatory rules disallow HT40 completely */
1164 	if (IEEE80211_CHAN_NO_HT40 == (chan->flags & (IEEE80211_CHAN_NO_HT40)))
1165 		return true;
1166 	return false;
1167 }
1168 
1169 static void reg_process_ht_flags_channel(struct wiphy *wiphy,
1170 					 enum ieee80211_band band,
1171 					 unsigned int chan_idx)
1172 {
1173 	struct ieee80211_supported_band *sband;
1174 	struct ieee80211_channel *channel;
1175 	struct ieee80211_channel *channel_before = NULL, *channel_after = NULL;
1176 	unsigned int i;
1177 
1178 	assert_cfg80211_lock();
1179 
1180 	sband = wiphy->bands[band];
1181 	BUG_ON(chan_idx >= sband->n_channels);
1182 	channel = &sband->channels[chan_idx];
1183 
1184 	if (is_ht40_not_allowed(channel)) {
1185 		channel->flags |= IEEE80211_CHAN_NO_HT40;
1186 		return;
1187 	}
1188 
1189 	/*
1190 	 * We need to ensure the extension channels exist to
1191 	 * be able to use HT40- or HT40+, this finds them (or not)
1192 	 */
1193 	for (i = 0; i < sband->n_channels; i++) {
1194 		struct ieee80211_channel *c = &sband->channels[i];
1195 		if (c->center_freq == (channel->center_freq - 20))
1196 			channel_before = c;
1197 		if (c->center_freq == (channel->center_freq + 20))
1198 			channel_after = c;
1199 	}
1200 
1201 	/*
1202 	 * Please note that this assumes target bandwidth is 20 MHz,
1203 	 * if that ever changes we also need to change the below logic
1204 	 * to include that as well.
1205 	 */
1206 	if (is_ht40_not_allowed(channel_before))
1207 		channel->flags |= IEEE80211_CHAN_NO_HT40MINUS;
1208 	else
1209 		channel->flags &= ~IEEE80211_CHAN_NO_HT40MINUS;
1210 
1211 	if (is_ht40_not_allowed(channel_after))
1212 		channel->flags |= IEEE80211_CHAN_NO_HT40PLUS;
1213 	else
1214 		channel->flags &= ~IEEE80211_CHAN_NO_HT40PLUS;
1215 }
1216 
1217 static void reg_process_ht_flags_band(struct wiphy *wiphy,
1218 				      enum ieee80211_band band)
1219 {
1220 	unsigned int i;
1221 	struct ieee80211_supported_band *sband;
1222 
1223 	BUG_ON(!wiphy->bands[band]);
1224 	sband = wiphy->bands[band];
1225 
1226 	for (i = 0; i < sband->n_channels; i++)
1227 		reg_process_ht_flags_channel(wiphy, band, i);
1228 }
1229 
1230 static void reg_process_ht_flags(struct wiphy *wiphy)
1231 {
1232 	enum ieee80211_band band;
1233 
1234 	if (!wiphy)
1235 		return;
1236 
1237 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1238 		if (wiphy->bands[band])
1239 			reg_process_ht_flags_band(wiphy, band);
1240 	}
1241 
1242 }
1243 
1244 static void wiphy_update_regulatory(struct wiphy *wiphy,
1245 				    enum nl80211_reg_initiator initiator)
1246 {
1247 	enum ieee80211_band band;
1248 
1249 	assert_reg_lock();
1250 
1251 	if (ignore_reg_update(wiphy, initiator))
1252 		return;
1253 
1254 	last_request->dfs_region = cfg80211_regdomain->dfs_region;
1255 
1256 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1257 		if (wiphy->bands[band])
1258 			handle_band(wiphy, band, initiator);
1259 	}
1260 
1261 	reg_process_beacons(wiphy);
1262 	reg_process_ht_flags(wiphy);
1263 	if (wiphy->reg_notifier)
1264 		wiphy->reg_notifier(wiphy, last_request);
1265 }
1266 
1267 static void update_all_wiphy_regulatory(enum nl80211_reg_initiator initiator)
1268 {
1269 	struct cfg80211_registered_device *rdev;
1270 	struct wiphy *wiphy;
1271 
1272 	list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
1273 		wiphy = &rdev->wiphy;
1274 		wiphy_update_regulatory(wiphy, initiator);
1275 		/*
1276 		 * Regulatory updates set by CORE are ignored for custom
1277 		 * regulatory cards. Let us notify the changes to the driver,
1278 		 * as some drivers used this to restore its orig_* reg domain.
1279 		 */
1280 		if (initiator == NL80211_REGDOM_SET_BY_CORE &&
1281 		    wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY &&
1282 		    wiphy->reg_notifier)
1283 			wiphy->reg_notifier(wiphy, last_request);
1284 	}
1285 }
1286 
1287 static void handle_channel_custom(struct wiphy *wiphy,
1288 				  enum ieee80211_band band,
1289 				  unsigned int chan_idx,
1290 				  const struct ieee80211_regdomain *regd)
1291 {
1292 	int r;
1293 	u32 desired_bw_khz = MHZ_TO_KHZ(20);
1294 	u32 bw_flags = 0;
1295 	const struct ieee80211_reg_rule *reg_rule = NULL;
1296 	const struct ieee80211_power_rule *power_rule = NULL;
1297 	const struct ieee80211_freq_range *freq_range = NULL;
1298 	struct ieee80211_supported_band *sband;
1299 	struct ieee80211_channel *chan;
1300 
1301 	assert_reg_lock();
1302 
1303 	sband = wiphy->bands[band];
1304 	BUG_ON(chan_idx >= sband->n_channels);
1305 	chan = &sband->channels[chan_idx];
1306 
1307 	r = freq_reg_info_regd(wiphy,
1308 			       MHZ_TO_KHZ(chan->center_freq),
1309 			       desired_bw_khz,
1310 			       &reg_rule,
1311 			       regd);
1312 
1313 	if (r) {
1314 		REG_DBG_PRINT("Disabling freq %d MHz as custom "
1315 			      "regd has no rule that fits a %d MHz "
1316 			      "wide channel\n",
1317 			      chan->center_freq,
1318 			      KHZ_TO_MHZ(desired_bw_khz));
1319 		chan->flags = IEEE80211_CHAN_DISABLED;
1320 		return;
1321 	}
1322 
1323 	chan_reg_rule_print_dbg(chan, desired_bw_khz, reg_rule);
1324 
1325 	power_rule = &reg_rule->power_rule;
1326 	freq_range = &reg_rule->freq_range;
1327 
1328 	if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
1329 		bw_flags = IEEE80211_CHAN_NO_HT40;
1330 
1331 	chan->flags |= map_regdom_flags(reg_rule->flags) | bw_flags;
1332 	chan->max_antenna_gain = (int) MBI_TO_DBI(power_rule->max_antenna_gain);
1333 	chan->max_reg_power = chan->max_power =
1334 		(int) MBM_TO_DBM(power_rule->max_eirp);
1335 }
1336 
1337 static void handle_band_custom(struct wiphy *wiphy, enum ieee80211_band band,
1338 			       const struct ieee80211_regdomain *regd)
1339 {
1340 	unsigned int i;
1341 	struct ieee80211_supported_band *sband;
1342 
1343 	BUG_ON(!wiphy->bands[band]);
1344 	sband = wiphy->bands[band];
1345 
1346 	for (i = 0; i < sband->n_channels; i++)
1347 		handle_channel_custom(wiphy, band, i, regd);
1348 }
1349 
1350 /* Used by drivers prior to wiphy registration */
1351 void wiphy_apply_custom_regulatory(struct wiphy *wiphy,
1352 				   const struct ieee80211_regdomain *regd)
1353 {
1354 	enum ieee80211_band band;
1355 	unsigned int bands_set = 0;
1356 
1357 	mutex_lock(&reg_mutex);
1358 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1359 		if (!wiphy->bands[band])
1360 			continue;
1361 		handle_band_custom(wiphy, band, regd);
1362 		bands_set++;
1363 	}
1364 	mutex_unlock(&reg_mutex);
1365 
1366 	/*
1367 	 * no point in calling this if it won't have any effect
1368 	 * on your device's supportd bands.
1369 	 */
1370 	WARN_ON(!bands_set);
1371 }
1372 EXPORT_SYMBOL(wiphy_apply_custom_regulatory);
1373 
1374 /*
1375  * Return value which can be used by ignore_request() to indicate
1376  * it has been determined we should intersect two regulatory domains
1377  */
1378 #define REG_INTERSECT	1
1379 
1380 /* This has the logic which determines when a new request
1381  * should be ignored. */
1382 static int ignore_request(struct wiphy *wiphy,
1383 			  struct regulatory_request *pending_request)
1384 {
1385 	struct wiphy *last_wiphy = NULL;
1386 
1387 	assert_cfg80211_lock();
1388 
1389 	/* All initial requests are respected */
1390 	if (!last_request)
1391 		return 0;
1392 
1393 	switch (pending_request->initiator) {
1394 	case NL80211_REGDOM_SET_BY_CORE:
1395 		return 0;
1396 	case NL80211_REGDOM_SET_BY_COUNTRY_IE:
1397 
1398 		if (reg_request_cell_base(last_request)) {
1399 			/* Trust a Cell base station over the AP's country IE */
1400 			if (regdom_changes(pending_request->alpha2))
1401 				return -EOPNOTSUPP;
1402 			return -EALREADY;
1403 		}
1404 
1405 		last_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
1406 
1407 		if (unlikely(!is_an_alpha2(pending_request->alpha2)))
1408 			return -EINVAL;
1409 		if (last_request->initiator ==
1410 		    NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1411 			if (last_wiphy != wiphy) {
1412 				/*
1413 				 * Two cards with two APs claiming different
1414 				 * Country IE alpha2s. We could
1415 				 * intersect them, but that seems unlikely
1416 				 * to be correct. Reject second one for now.
1417 				 */
1418 				if (regdom_changes(pending_request->alpha2))
1419 					return -EOPNOTSUPP;
1420 				return -EALREADY;
1421 			}
1422 			/*
1423 			 * Two consecutive Country IE hints on the same wiphy.
1424 			 * This should be picked up early by the driver/stack
1425 			 */
1426 			if (WARN_ON(regdom_changes(pending_request->alpha2)))
1427 				return 0;
1428 			return -EALREADY;
1429 		}
1430 		return 0;
1431 	case NL80211_REGDOM_SET_BY_DRIVER:
1432 		if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE) {
1433 			if (regdom_changes(pending_request->alpha2))
1434 				return 0;
1435 			return -EALREADY;
1436 		}
1437 
1438 		/*
1439 		 * This would happen if you unplug and plug your card
1440 		 * back in or if you add a new device for which the previously
1441 		 * loaded card also agrees on the regulatory domain.
1442 		 */
1443 		if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1444 		    !regdom_changes(pending_request->alpha2))
1445 			return -EALREADY;
1446 
1447 		return REG_INTERSECT;
1448 	case NL80211_REGDOM_SET_BY_USER:
1449 		if (reg_request_cell_base(pending_request))
1450 			return reg_ignore_cell_hint(pending_request);
1451 
1452 		if (reg_request_cell_base(last_request))
1453 			return -EOPNOTSUPP;
1454 
1455 		if (last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE)
1456 			return REG_INTERSECT;
1457 		/*
1458 		 * If the user knows better the user should set the regdom
1459 		 * to their country before the IE is picked up
1460 		 */
1461 		if (last_request->initiator == NL80211_REGDOM_SET_BY_USER &&
1462 			  last_request->intersect)
1463 			return -EOPNOTSUPP;
1464 		/*
1465 		 * Process user requests only after previous user/driver/core
1466 		 * requests have been processed
1467 		 */
1468 		if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE ||
1469 		    last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER ||
1470 		    last_request->initiator == NL80211_REGDOM_SET_BY_USER) {
1471 			if (regdom_changes(last_request->alpha2))
1472 				return -EAGAIN;
1473 		}
1474 
1475 		if (!regdom_changes(pending_request->alpha2))
1476 			return -EALREADY;
1477 
1478 		return 0;
1479 	}
1480 
1481 	return -EINVAL;
1482 }
1483 
1484 static void reg_set_request_processed(void)
1485 {
1486 	bool need_more_processing = false;
1487 
1488 	last_request->processed = true;
1489 
1490 	spin_lock(&reg_requests_lock);
1491 	if (!list_empty(&reg_requests_list))
1492 		need_more_processing = true;
1493 	spin_unlock(&reg_requests_lock);
1494 
1495 	if (last_request->initiator == NL80211_REGDOM_SET_BY_USER)
1496 		cancel_delayed_work(&reg_timeout);
1497 
1498 	if (need_more_processing)
1499 		schedule_work(&reg_work);
1500 }
1501 
1502 /**
1503  * __regulatory_hint - hint to the wireless core a regulatory domain
1504  * @wiphy: if the hint comes from country information from an AP, this
1505  *	is required to be set to the wiphy that received the information
1506  * @pending_request: the regulatory request currently being processed
1507  *
1508  * The Wireless subsystem can use this function to hint to the wireless core
1509  * what it believes should be the current regulatory domain.
1510  *
1511  * Returns zero if all went fine, %-EALREADY if a regulatory domain had
1512  * already been set or other standard error codes.
1513  *
1514  * Caller must hold &cfg80211_mutex and &reg_mutex
1515  */
1516 static int __regulatory_hint(struct wiphy *wiphy,
1517 			     struct regulatory_request *pending_request)
1518 {
1519 	bool intersect = false;
1520 	int r = 0;
1521 
1522 	assert_cfg80211_lock();
1523 
1524 	r = ignore_request(wiphy, pending_request);
1525 
1526 	if (r == REG_INTERSECT) {
1527 		if (pending_request->initiator ==
1528 		    NL80211_REGDOM_SET_BY_DRIVER) {
1529 			r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1530 			if (r) {
1531 				kfree(pending_request);
1532 				return r;
1533 			}
1534 		}
1535 		intersect = true;
1536 	} else if (r) {
1537 		/*
1538 		 * If the regulatory domain being requested by the
1539 		 * driver has already been set just copy it to the
1540 		 * wiphy
1541 		 */
1542 		if (r == -EALREADY &&
1543 		    pending_request->initiator ==
1544 		    NL80211_REGDOM_SET_BY_DRIVER) {
1545 			r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1546 			if (r) {
1547 				kfree(pending_request);
1548 				return r;
1549 			}
1550 			r = -EALREADY;
1551 			goto new_request;
1552 		}
1553 		kfree(pending_request);
1554 		return r;
1555 	}
1556 
1557 new_request:
1558 	if (last_request != &core_request_world)
1559 		kfree(last_request);
1560 
1561 	last_request = pending_request;
1562 	last_request->intersect = intersect;
1563 
1564 	pending_request = NULL;
1565 
1566 	if (last_request->initiator == NL80211_REGDOM_SET_BY_USER) {
1567 		user_alpha2[0] = last_request->alpha2[0];
1568 		user_alpha2[1] = last_request->alpha2[1];
1569 	}
1570 
1571 	/* When r == REG_INTERSECT we do need to call CRDA */
1572 	if (r < 0) {
1573 		/*
1574 		 * Since CRDA will not be called in this case as we already
1575 		 * have applied the requested regulatory domain before we just
1576 		 * inform userspace we have processed the request
1577 		 */
1578 		if (r == -EALREADY) {
1579 			nl80211_send_reg_change_event(last_request);
1580 			reg_set_request_processed();
1581 		}
1582 		return r;
1583 	}
1584 
1585 	return call_crda(last_request->alpha2);
1586 }
1587 
1588 /* This processes *all* regulatory hints */
1589 static void reg_process_hint(struct regulatory_request *reg_request,
1590 			     enum nl80211_reg_initiator reg_initiator)
1591 {
1592 	int r = 0;
1593 	struct wiphy *wiphy = NULL;
1594 
1595 	BUG_ON(!reg_request->alpha2);
1596 
1597 	if (wiphy_idx_valid(reg_request->wiphy_idx))
1598 		wiphy = wiphy_idx_to_wiphy(reg_request->wiphy_idx);
1599 
1600 	if (reg_initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1601 	    !wiphy) {
1602 		kfree(reg_request);
1603 		return;
1604 	}
1605 
1606 	r = __regulatory_hint(wiphy, reg_request);
1607 	/* This is required so that the orig_* parameters are saved */
1608 	if (r == -EALREADY && wiphy &&
1609 	    wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY) {
1610 		wiphy_update_regulatory(wiphy, reg_initiator);
1611 		return;
1612 	}
1613 
1614 	/*
1615 	 * We only time out user hints, given that they should be the only
1616 	 * source of bogus requests.
1617 	 */
1618 	if (r != -EALREADY &&
1619 	    reg_initiator == NL80211_REGDOM_SET_BY_USER)
1620 		schedule_delayed_work(&reg_timeout, msecs_to_jiffies(3142));
1621 }
1622 
1623 /*
1624  * Processes regulatory hints, this is all the NL80211_REGDOM_SET_BY_*
1625  * Regulatory hints come on a first come first serve basis and we
1626  * must process each one atomically.
1627  */
1628 static void reg_process_pending_hints(void)
1629 {
1630 	struct regulatory_request *reg_request;
1631 
1632 	mutex_lock(&cfg80211_mutex);
1633 	mutex_lock(&reg_mutex);
1634 
1635 	/* When last_request->processed becomes true this will be rescheduled */
1636 	if (last_request && !last_request->processed) {
1637 		REG_DBG_PRINT("Pending regulatory request, waiting "
1638 			      "for it to be processed...\n");
1639 		goto out;
1640 	}
1641 
1642 	spin_lock(&reg_requests_lock);
1643 
1644 	if (list_empty(&reg_requests_list)) {
1645 		spin_unlock(&reg_requests_lock);
1646 		goto out;
1647 	}
1648 
1649 	reg_request = list_first_entry(&reg_requests_list,
1650 				       struct regulatory_request,
1651 				       list);
1652 	list_del_init(&reg_request->list);
1653 
1654 	spin_unlock(&reg_requests_lock);
1655 
1656 	reg_process_hint(reg_request, reg_request->initiator);
1657 
1658 out:
1659 	mutex_unlock(&reg_mutex);
1660 	mutex_unlock(&cfg80211_mutex);
1661 }
1662 
1663 /* Processes beacon hints -- this has nothing to do with country IEs */
1664 static void reg_process_pending_beacon_hints(void)
1665 {
1666 	struct cfg80211_registered_device *rdev;
1667 	struct reg_beacon *pending_beacon, *tmp;
1668 
1669 	/*
1670 	 * No need to hold the reg_mutex here as we just touch wiphys
1671 	 * and do not read or access regulatory variables.
1672 	 */
1673 	mutex_lock(&cfg80211_mutex);
1674 
1675 	/* This goes through the _pending_ beacon list */
1676 	spin_lock_bh(&reg_pending_beacons_lock);
1677 
1678 	if (list_empty(&reg_pending_beacons)) {
1679 		spin_unlock_bh(&reg_pending_beacons_lock);
1680 		goto out;
1681 	}
1682 
1683 	list_for_each_entry_safe(pending_beacon, tmp,
1684 				 &reg_pending_beacons, list) {
1685 
1686 		list_del_init(&pending_beacon->list);
1687 
1688 		/* Applies the beacon hint to current wiphys */
1689 		list_for_each_entry(rdev, &cfg80211_rdev_list, list)
1690 			wiphy_update_new_beacon(&rdev->wiphy, pending_beacon);
1691 
1692 		/* Remembers the beacon hint for new wiphys or reg changes */
1693 		list_add_tail(&pending_beacon->list, &reg_beacon_list);
1694 	}
1695 
1696 	spin_unlock_bh(&reg_pending_beacons_lock);
1697 out:
1698 	mutex_unlock(&cfg80211_mutex);
1699 }
1700 
1701 static void reg_todo(struct work_struct *work)
1702 {
1703 	reg_process_pending_hints();
1704 	reg_process_pending_beacon_hints();
1705 }
1706 
1707 static void queue_regulatory_request(struct regulatory_request *request)
1708 {
1709 	if (isalpha(request->alpha2[0]))
1710 		request->alpha2[0] = toupper(request->alpha2[0]);
1711 	if (isalpha(request->alpha2[1]))
1712 		request->alpha2[1] = toupper(request->alpha2[1]);
1713 
1714 	spin_lock(&reg_requests_lock);
1715 	list_add_tail(&request->list, &reg_requests_list);
1716 	spin_unlock(&reg_requests_lock);
1717 
1718 	schedule_work(&reg_work);
1719 }
1720 
1721 /*
1722  * Core regulatory hint -- happens during cfg80211_init()
1723  * and when we restore regulatory settings.
1724  */
1725 static int regulatory_hint_core(const char *alpha2)
1726 {
1727 	struct regulatory_request *request;
1728 
1729 	request = kzalloc(sizeof(struct regulatory_request),
1730 			  GFP_KERNEL);
1731 	if (!request)
1732 		return -ENOMEM;
1733 
1734 	request->alpha2[0] = alpha2[0];
1735 	request->alpha2[1] = alpha2[1];
1736 	request->initiator = NL80211_REGDOM_SET_BY_CORE;
1737 
1738 	queue_regulatory_request(request);
1739 
1740 	return 0;
1741 }
1742 
1743 /* User hints */
1744 int regulatory_hint_user(const char *alpha2,
1745 			 enum nl80211_user_reg_hint_type user_reg_hint_type)
1746 {
1747 	struct regulatory_request *request;
1748 
1749 	BUG_ON(!alpha2);
1750 
1751 	request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1752 	if (!request)
1753 		return -ENOMEM;
1754 
1755 	request->wiphy_idx = WIPHY_IDX_STALE;
1756 	request->alpha2[0] = alpha2[0];
1757 	request->alpha2[1] = alpha2[1];
1758 	request->initiator = NL80211_REGDOM_SET_BY_USER;
1759 	request->user_reg_hint_type = user_reg_hint_type;
1760 
1761 	queue_regulatory_request(request);
1762 
1763 	return 0;
1764 }
1765 
1766 /* Driver hints */
1767 int regulatory_hint(struct wiphy *wiphy, const char *alpha2)
1768 {
1769 	struct regulatory_request *request;
1770 
1771 	BUG_ON(!alpha2);
1772 	BUG_ON(!wiphy);
1773 
1774 	request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1775 	if (!request)
1776 		return -ENOMEM;
1777 
1778 	request->wiphy_idx = get_wiphy_idx(wiphy);
1779 
1780 	/* Must have registered wiphy first */
1781 	BUG_ON(!wiphy_idx_valid(request->wiphy_idx));
1782 
1783 	request->alpha2[0] = alpha2[0];
1784 	request->alpha2[1] = alpha2[1];
1785 	request->initiator = NL80211_REGDOM_SET_BY_DRIVER;
1786 
1787 	queue_regulatory_request(request);
1788 
1789 	return 0;
1790 }
1791 EXPORT_SYMBOL(regulatory_hint);
1792 
1793 /*
1794  * We hold wdev_lock() here so we cannot hold cfg80211_mutex() and
1795  * therefore cannot iterate over the rdev list here.
1796  */
1797 void regulatory_hint_11d(struct wiphy *wiphy,
1798 			 enum ieee80211_band band,
1799 			 const u8 *country_ie,
1800 			 u8 country_ie_len)
1801 {
1802 	char alpha2[2];
1803 	enum environment_cap env = ENVIRON_ANY;
1804 	struct regulatory_request *request;
1805 
1806 	mutex_lock(&reg_mutex);
1807 
1808 	if (unlikely(!last_request))
1809 		goto out;
1810 
1811 	/* IE len must be evenly divisible by 2 */
1812 	if (country_ie_len & 0x01)
1813 		goto out;
1814 
1815 	if (country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN)
1816 		goto out;
1817 
1818 	alpha2[0] = country_ie[0];
1819 	alpha2[1] = country_ie[1];
1820 
1821 	if (country_ie[2] == 'I')
1822 		env = ENVIRON_INDOOR;
1823 	else if (country_ie[2] == 'O')
1824 		env = ENVIRON_OUTDOOR;
1825 
1826 	/*
1827 	 * We will run this only upon a successful connection on cfg80211.
1828 	 * We leave conflict resolution to the workqueue, where can hold
1829 	 * cfg80211_mutex.
1830 	 */
1831 	if (likely(last_request->initiator ==
1832 	    NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1833 	    wiphy_idx_valid(last_request->wiphy_idx)))
1834 		goto out;
1835 
1836 	request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1837 	if (!request)
1838 		goto out;
1839 
1840 	request->wiphy_idx = get_wiphy_idx(wiphy);
1841 	request->alpha2[0] = alpha2[0];
1842 	request->alpha2[1] = alpha2[1];
1843 	request->initiator = NL80211_REGDOM_SET_BY_COUNTRY_IE;
1844 	request->country_ie_env = env;
1845 
1846 	mutex_unlock(&reg_mutex);
1847 
1848 	queue_regulatory_request(request);
1849 
1850 	return;
1851 
1852 out:
1853 	mutex_unlock(&reg_mutex);
1854 }
1855 
1856 static void restore_alpha2(char *alpha2, bool reset_user)
1857 {
1858 	/* indicates there is no alpha2 to consider for restoration */
1859 	alpha2[0] = '9';
1860 	alpha2[1] = '7';
1861 
1862 	/* The user setting has precedence over the module parameter */
1863 	if (is_user_regdom_saved()) {
1864 		/* Unless we're asked to ignore it and reset it */
1865 		if (reset_user) {
1866 			REG_DBG_PRINT("Restoring regulatory settings "
1867 			       "including user preference\n");
1868 			user_alpha2[0] = '9';
1869 			user_alpha2[1] = '7';
1870 
1871 			/*
1872 			 * If we're ignoring user settings, we still need to
1873 			 * check the module parameter to ensure we put things
1874 			 * back as they were for a full restore.
1875 			 */
1876 			if (!is_world_regdom(ieee80211_regdom)) {
1877 				REG_DBG_PRINT("Keeping preference on "
1878 				       "module parameter ieee80211_regdom: %c%c\n",
1879 				       ieee80211_regdom[0],
1880 				       ieee80211_regdom[1]);
1881 				alpha2[0] = ieee80211_regdom[0];
1882 				alpha2[1] = ieee80211_regdom[1];
1883 			}
1884 		} else {
1885 			REG_DBG_PRINT("Restoring regulatory settings "
1886 			       "while preserving user preference for: %c%c\n",
1887 			       user_alpha2[0],
1888 			       user_alpha2[1]);
1889 			alpha2[0] = user_alpha2[0];
1890 			alpha2[1] = user_alpha2[1];
1891 		}
1892 	} else if (!is_world_regdom(ieee80211_regdom)) {
1893 		REG_DBG_PRINT("Keeping preference on "
1894 		       "module parameter ieee80211_regdom: %c%c\n",
1895 		       ieee80211_regdom[0],
1896 		       ieee80211_regdom[1]);
1897 		alpha2[0] = ieee80211_regdom[0];
1898 		alpha2[1] = ieee80211_regdom[1];
1899 	} else
1900 		REG_DBG_PRINT("Restoring regulatory settings\n");
1901 }
1902 
1903 static void restore_custom_reg_settings(struct wiphy *wiphy)
1904 {
1905 	struct ieee80211_supported_band *sband;
1906 	enum ieee80211_band band;
1907 	struct ieee80211_channel *chan;
1908 	int i;
1909 
1910 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1911 		sband = wiphy->bands[band];
1912 		if (!sband)
1913 			continue;
1914 		for (i = 0; i < sband->n_channels; i++) {
1915 			chan = &sband->channels[i];
1916 			chan->flags = chan->orig_flags;
1917 			chan->max_antenna_gain = chan->orig_mag;
1918 			chan->max_power = chan->orig_mpwr;
1919 			chan->beacon_found = false;
1920 		}
1921 	}
1922 }
1923 
1924 /*
1925  * Restoring regulatory settings involves ingoring any
1926  * possibly stale country IE information and user regulatory
1927  * settings if so desired, this includes any beacon hints
1928  * learned as we could have traveled outside to another country
1929  * after disconnection. To restore regulatory settings we do
1930  * exactly what we did at bootup:
1931  *
1932  *   - send a core regulatory hint
1933  *   - send a user regulatory hint if applicable
1934  *
1935  * Device drivers that send a regulatory hint for a specific country
1936  * keep their own regulatory domain on wiphy->regd so that does does
1937  * not need to be remembered.
1938  */
1939 static void restore_regulatory_settings(bool reset_user)
1940 {
1941 	char alpha2[2];
1942 	char world_alpha2[2];
1943 	struct reg_beacon *reg_beacon, *btmp;
1944 	struct regulatory_request *reg_request, *tmp;
1945 	LIST_HEAD(tmp_reg_req_list);
1946 	struct cfg80211_registered_device *rdev;
1947 
1948 	mutex_lock(&cfg80211_mutex);
1949 	mutex_lock(&reg_mutex);
1950 
1951 	reset_regdomains(true);
1952 	restore_alpha2(alpha2, reset_user);
1953 
1954 	/*
1955 	 * If there's any pending requests we simply
1956 	 * stash them to a temporary pending queue and
1957 	 * add then after we've restored regulatory
1958 	 * settings.
1959 	 */
1960 	spin_lock(&reg_requests_lock);
1961 	if (!list_empty(&reg_requests_list)) {
1962 		list_for_each_entry_safe(reg_request, tmp,
1963 					 &reg_requests_list, list) {
1964 			if (reg_request->initiator !=
1965 			    NL80211_REGDOM_SET_BY_USER)
1966 				continue;
1967 			list_move_tail(&reg_request->list, &tmp_reg_req_list);
1968 		}
1969 	}
1970 	spin_unlock(&reg_requests_lock);
1971 
1972 	/* Clear beacon hints */
1973 	spin_lock_bh(&reg_pending_beacons_lock);
1974 	if (!list_empty(&reg_pending_beacons)) {
1975 		list_for_each_entry_safe(reg_beacon, btmp,
1976 					 &reg_pending_beacons, list) {
1977 			list_del(&reg_beacon->list);
1978 			kfree(reg_beacon);
1979 		}
1980 	}
1981 	spin_unlock_bh(&reg_pending_beacons_lock);
1982 
1983 	if (!list_empty(&reg_beacon_list)) {
1984 		list_for_each_entry_safe(reg_beacon, btmp,
1985 					 &reg_beacon_list, list) {
1986 			list_del(&reg_beacon->list);
1987 			kfree(reg_beacon);
1988 		}
1989 	}
1990 
1991 	/* First restore to the basic regulatory settings */
1992 	cfg80211_regdomain = cfg80211_world_regdom;
1993 	world_alpha2[0] = cfg80211_regdomain->alpha2[0];
1994 	world_alpha2[1] = cfg80211_regdomain->alpha2[1];
1995 
1996 	list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
1997 		if (rdev->wiphy.flags & WIPHY_FLAG_CUSTOM_REGULATORY)
1998 			restore_custom_reg_settings(&rdev->wiphy);
1999 	}
2000 
2001 	mutex_unlock(&reg_mutex);
2002 	mutex_unlock(&cfg80211_mutex);
2003 
2004 	regulatory_hint_core(world_alpha2);
2005 
2006 	/*
2007 	 * This restores the ieee80211_regdom module parameter
2008 	 * preference or the last user requested regulatory
2009 	 * settings, user regulatory settings takes precedence.
2010 	 */
2011 	if (is_an_alpha2(alpha2))
2012 		regulatory_hint_user(user_alpha2, NL80211_USER_REG_HINT_USER);
2013 
2014 	if (list_empty(&tmp_reg_req_list))
2015 		return;
2016 
2017 	mutex_lock(&cfg80211_mutex);
2018 	mutex_lock(&reg_mutex);
2019 
2020 	spin_lock(&reg_requests_lock);
2021 	list_for_each_entry_safe(reg_request, tmp, &tmp_reg_req_list, list) {
2022 		REG_DBG_PRINT("Adding request for country %c%c back "
2023 			      "into the queue\n",
2024 			      reg_request->alpha2[0],
2025 			      reg_request->alpha2[1]);
2026 		list_move_tail(&reg_request->list, &reg_requests_list);
2027 	}
2028 	spin_unlock(&reg_requests_lock);
2029 
2030 	mutex_unlock(&reg_mutex);
2031 	mutex_unlock(&cfg80211_mutex);
2032 
2033 	REG_DBG_PRINT("Kicking the queue\n");
2034 
2035 	schedule_work(&reg_work);
2036 }
2037 
2038 void regulatory_hint_disconnect(void)
2039 {
2040 	REG_DBG_PRINT("All devices are disconnected, going to "
2041 		      "restore regulatory settings\n");
2042 	restore_regulatory_settings(false);
2043 }
2044 
2045 static bool freq_is_chan_12_13_14(u16 freq)
2046 {
2047 	if (freq == ieee80211_channel_to_frequency(12, IEEE80211_BAND_2GHZ) ||
2048 	    freq == ieee80211_channel_to_frequency(13, IEEE80211_BAND_2GHZ) ||
2049 	    freq == ieee80211_channel_to_frequency(14, IEEE80211_BAND_2GHZ))
2050 		return true;
2051 	return false;
2052 }
2053 
2054 int regulatory_hint_found_beacon(struct wiphy *wiphy,
2055 				 struct ieee80211_channel *beacon_chan,
2056 				 gfp_t gfp)
2057 {
2058 	struct reg_beacon *reg_beacon;
2059 
2060 	if (likely((beacon_chan->beacon_found ||
2061 	    (beacon_chan->flags & IEEE80211_CHAN_RADAR) ||
2062 	    (beacon_chan->band == IEEE80211_BAND_2GHZ &&
2063 	     !freq_is_chan_12_13_14(beacon_chan->center_freq)))))
2064 		return 0;
2065 
2066 	reg_beacon = kzalloc(sizeof(struct reg_beacon), gfp);
2067 	if (!reg_beacon)
2068 		return -ENOMEM;
2069 
2070 	REG_DBG_PRINT("Found new beacon on "
2071 		      "frequency: %d MHz (Ch %d) on %s\n",
2072 		      beacon_chan->center_freq,
2073 		      ieee80211_frequency_to_channel(beacon_chan->center_freq),
2074 		      wiphy_name(wiphy));
2075 
2076 	memcpy(&reg_beacon->chan, beacon_chan,
2077 		sizeof(struct ieee80211_channel));
2078 
2079 
2080 	/*
2081 	 * Since we can be called from BH or and non-BH context
2082 	 * we must use spin_lock_bh()
2083 	 */
2084 	spin_lock_bh(&reg_pending_beacons_lock);
2085 	list_add_tail(&reg_beacon->list, &reg_pending_beacons);
2086 	spin_unlock_bh(&reg_pending_beacons_lock);
2087 
2088 	schedule_work(&reg_work);
2089 
2090 	return 0;
2091 }
2092 
2093 static void print_rd_rules(const struct ieee80211_regdomain *rd)
2094 {
2095 	unsigned int i;
2096 	const struct ieee80211_reg_rule *reg_rule = NULL;
2097 	const struct ieee80211_freq_range *freq_range = NULL;
2098 	const struct ieee80211_power_rule *power_rule = NULL;
2099 
2100 	pr_info("  (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)\n");
2101 
2102 	for (i = 0; i < rd->n_reg_rules; i++) {
2103 		reg_rule = &rd->reg_rules[i];
2104 		freq_range = &reg_rule->freq_range;
2105 		power_rule = &reg_rule->power_rule;
2106 
2107 		/*
2108 		 * There may not be documentation for max antenna gain
2109 		 * in certain regions
2110 		 */
2111 		if (power_rule->max_antenna_gain)
2112 			pr_info("  (%d KHz - %d KHz @ %d KHz), (%d mBi, %d mBm)\n",
2113 				freq_range->start_freq_khz,
2114 				freq_range->end_freq_khz,
2115 				freq_range->max_bandwidth_khz,
2116 				power_rule->max_antenna_gain,
2117 				power_rule->max_eirp);
2118 		else
2119 			pr_info("  (%d KHz - %d KHz @ %d KHz), (N/A, %d mBm)\n",
2120 				freq_range->start_freq_khz,
2121 				freq_range->end_freq_khz,
2122 				freq_range->max_bandwidth_khz,
2123 				power_rule->max_eirp);
2124 	}
2125 }
2126 
2127 bool reg_supported_dfs_region(u8 dfs_region)
2128 {
2129 	switch (dfs_region) {
2130 	case NL80211_DFS_UNSET:
2131 	case NL80211_DFS_FCC:
2132 	case NL80211_DFS_ETSI:
2133 	case NL80211_DFS_JP:
2134 		return true;
2135 	default:
2136 		REG_DBG_PRINT("Ignoring uknown DFS master region: %d\n",
2137 			      dfs_region);
2138 		return false;
2139 	}
2140 }
2141 
2142 static void print_dfs_region(u8 dfs_region)
2143 {
2144 	if (!dfs_region)
2145 		return;
2146 
2147 	switch (dfs_region) {
2148 	case NL80211_DFS_FCC:
2149 		pr_info(" DFS Master region FCC");
2150 		break;
2151 	case NL80211_DFS_ETSI:
2152 		pr_info(" DFS Master region ETSI");
2153 		break;
2154 	case NL80211_DFS_JP:
2155 		pr_info(" DFS Master region JP");
2156 		break;
2157 	default:
2158 		pr_info(" DFS Master region Uknown");
2159 		break;
2160 	}
2161 }
2162 
2163 static void print_regdomain(const struct ieee80211_regdomain *rd)
2164 {
2165 
2166 	if (is_intersected_alpha2(rd->alpha2)) {
2167 
2168 		if (last_request->initiator ==
2169 		    NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2170 			struct cfg80211_registered_device *rdev;
2171 			rdev = cfg80211_rdev_by_wiphy_idx(
2172 				last_request->wiphy_idx);
2173 			if (rdev) {
2174 				pr_info("Current regulatory domain updated by AP to: %c%c\n",
2175 					rdev->country_ie_alpha2[0],
2176 					rdev->country_ie_alpha2[1]);
2177 			} else
2178 				pr_info("Current regulatory domain intersected:\n");
2179 		} else
2180 			pr_info("Current regulatory domain intersected:\n");
2181 	} else if (is_world_regdom(rd->alpha2))
2182 		pr_info("World regulatory domain updated:\n");
2183 	else {
2184 		if (is_unknown_alpha2(rd->alpha2))
2185 			pr_info("Regulatory domain changed to driver built-in settings (unknown country)\n");
2186 		else {
2187 			if (reg_request_cell_base(last_request))
2188 				pr_info("Regulatory domain changed "
2189 					"to country: %c%c by Cell Station\n",
2190 					rd->alpha2[0], rd->alpha2[1]);
2191 			else
2192 				pr_info("Regulatory domain changed "
2193 					"to country: %c%c\n",
2194 					rd->alpha2[0], rd->alpha2[1]);
2195 		}
2196 	}
2197 	print_dfs_region(rd->dfs_region);
2198 	print_rd_rules(rd);
2199 }
2200 
2201 static void print_regdomain_info(const struct ieee80211_regdomain *rd)
2202 {
2203 	pr_info("Regulatory domain: %c%c\n", rd->alpha2[0], rd->alpha2[1]);
2204 	print_rd_rules(rd);
2205 }
2206 
2207 /* Takes ownership of rd only if it doesn't fail */
2208 static int __set_regdom(const struct ieee80211_regdomain *rd)
2209 {
2210 	const struct ieee80211_regdomain *intersected_rd = NULL;
2211 	struct wiphy *request_wiphy;
2212 	/* Some basic sanity checks first */
2213 
2214 	if (is_world_regdom(rd->alpha2)) {
2215 		if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
2216 			return -EINVAL;
2217 		update_world_regdomain(rd);
2218 		return 0;
2219 	}
2220 
2221 	if (!is_alpha2_set(rd->alpha2) && !is_an_alpha2(rd->alpha2) &&
2222 			!is_unknown_alpha2(rd->alpha2))
2223 		return -EINVAL;
2224 
2225 	if (!last_request)
2226 		return -EINVAL;
2227 
2228 	/*
2229 	 * Lets only bother proceeding on the same alpha2 if the current
2230 	 * rd is non static (it means CRDA was present and was used last)
2231 	 * and the pending request came in from a country IE
2232 	 */
2233 	if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2234 		/*
2235 		 * If someone else asked us to change the rd lets only bother
2236 		 * checking if the alpha2 changes if CRDA was already called
2237 		 */
2238 		if (!regdom_changes(rd->alpha2))
2239 			return -EALREADY;
2240 	}
2241 
2242 	/*
2243 	 * Now lets set the regulatory domain, update all driver channels
2244 	 * and finally inform them of what we have done, in case they want
2245 	 * to review or adjust their own settings based on their own
2246 	 * internal EEPROM data
2247 	 */
2248 
2249 	if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
2250 		return -EINVAL;
2251 
2252 	if (!is_valid_rd(rd)) {
2253 		pr_err("Invalid regulatory domain detected:\n");
2254 		print_regdomain_info(rd);
2255 		return -EINVAL;
2256 	}
2257 
2258 	request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
2259 	if (!request_wiphy &&
2260 	    (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER ||
2261 	     last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE)) {
2262 		schedule_delayed_work(&reg_timeout, 0);
2263 		return -ENODEV;
2264 	}
2265 
2266 	if (!last_request->intersect) {
2267 		int r;
2268 
2269 		if (last_request->initiator != NL80211_REGDOM_SET_BY_DRIVER) {
2270 			reset_regdomains(false);
2271 			cfg80211_regdomain = rd;
2272 			return 0;
2273 		}
2274 
2275 		/*
2276 		 * For a driver hint, lets copy the regulatory domain the
2277 		 * driver wanted to the wiphy to deal with conflicts
2278 		 */
2279 
2280 		/*
2281 		 * Userspace could have sent two replies with only
2282 		 * one kernel request.
2283 		 */
2284 		if (request_wiphy->regd)
2285 			return -EALREADY;
2286 
2287 		r = reg_copy_regd(&request_wiphy->regd, rd);
2288 		if (r)
2289 			return r;
2290 
2291 		reset_regdomains(false);
2292 		cfg80211_regdomain = rd;
2293 		return 0;
2294 	}
2295 
2296 	/* Intersection requires a bit more work */
2297 
2298 	if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2299 
2300 		intersected_rd = regdom_intersect(rd, cfg80211_regdomain);
2301 		if (!intersected_rd)
2302 			return -EINVAL;
2303 
2304 		/*
2305 		 * We can trash what CRDA provided now.
2306 		 * However if a driver requested this specific regulatory
2307 		 * domain we keep it for its private use
2308 		 */
2309 		if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER)
2310 			request_wiphy->regd = rd;
2311 		else
2312 			kfree(rd);
2313 
2314 		rd = NULL;
2315 
2316 		reset_regdomains(false);
2317 		cfg80211_regdomain = intersected_rd;
2318 
2319 		return 0;
2320 	}
2321 
2322 	return -EINVAL;
2323 }
2324 
2325 
2326 /*
2327  * Use this call to set the current regulatory domain. Conflicts with
2328  * multiple drivers can be ironed out later. Caller must've already
2329  * kmalloc'd the rd structure. Caller must hold cfg80211_mutex
2330  */
2331 int set_regdom(const struct ieee80211_regdomain *rd)
2332 {
2333 	int r;
2334 
2335 	assert_cfg80211_lock();
2336 
2337 	mutex_lock(&reg_mutex);
2338 
2339 	/* Note that this doesn't update the wiphys, this is done below */
2340 	r = __set_regdom(rd);
2341 	if (r) {
2342 		if (r == -EALREADY)
2343 			reg_set_request_processed();
2344 
2345 		kfree(rd);
2346 		mutex_unlock(&reg_mutex);
2347 		return r;
2348 	}
2349 
2350 	/* This would make this whole thing pointless */
2351 	if (!last_request->intersect)
2352 		BUG_ON(rd != cfg80211_regdomain);
2353 
2354 	/* update all wiphys now with the new established regulatory domain */
2355 	update_all_wiphy_regulatory(last_request->initiator);
2356 
2357 	print_regdomain(cfg80211_regdomain);
2358 
2359 	nl80211_send_reg_change_event(last_request);
2360 
2361 	reg_set_request_processed();
2362 
2363 	mutex_unlock(&reg_mutex);
2364 
2365 	return r;
2366 }
2367 
2368 #ifdef CONFIG_HOTPLUG
2369 int reg_device_uevent(struct device *dev, struct kobj_uevent_env *env)
2370 {
2371 	if (last_request && !last_request->processed) {
2372 		if (add_uevent_var(env, "COUNTRY=%c%c",
2373 				   last_request->alpha2[0],
2374 				   last_request->alpha2[1]))
2375 			return -ENOMEM;
2376 	}
2377 
2378 	return 0;
2379 }
2380 #else
2381 int reg_device_uevent(struct device *dev, struct kobj_uevent_env *env)
2382 {
2383 	return -ENODEV;
2384 }
2385 #endif /* CONFIG_HOTPLUG */
2386 
2387 void wiphy_regulatory_register(struct wiphy *wiphy)
2388 {
2389 	assert_cfg80211_lock();
2390 
2391 	mutex_lock(&reg_mutex);
2392 
2393 	if (!reg_dev_ignore_cell_hint(wiphy))
2394 		reg_num_devs_support_basehint++;
2395 
2396 	wiphy_update_regulatory(wiphy, NL80211_REGDOM_SET_BY_CORE);
2397 
2398 	mutex_unlock(&reg_mutex);
2399 }
2400 
2401 /* Caller must hold cfg80211_mutex */
2402 void wiphy_regulatory_deregister(struct wiphy *wiphy)
2403 {
2404 	struct wiphy *request_wiphy = NULL;
2405 
2406 	assert_cfg80211_lock();
2407 
2408 	mutex_lock(&reg_mutex);
2409 
2410 	if (!reg_dev_ignore_cell_hint(wiphy))
2411 		reg_num_devs_support_basehint--;
2412 
2413 	kfree(wiphy->regd);
2414 
2415 	if (last_request)
2416 		request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
2417 
2418 	if (!request_wiphy || request_wiphy != wiphy)
2419 		goto out;
2420 
2421 	last_request->wiphy_idx = WIPHY_IDX_STALE;
2422 	last_request->country_ie_env = ENVIRON_ANY;
2423 out:
2424 	mutex_unlock(&reg_mutex);
2425 }
2426 
2427 static void reg_timeout_work(struct work_struct *work)
2428 {
2429 	REG_DBG_PRINT("Timeout while waiting for CRDA to reply, "
2430 		      "restoring regulatory settings\n");
2431 	restore_regulatory_settings(true);
2432 }
2433 
2434 int __init regulatory_init(void)
2435 {
2436 	int err = 0;
2437 
2438 	reg_pdev = platform_device_register_simple("regulatory", 0, NULL, 0);
2439 	if (IS_ERR(reg_pdev))
2440 		return PTR_ERR(reg_pdev);
2441 
2442 	reg_pdev->dev.type = &reg_device_type;
2443 
2444 	spin_lock_init(&reg_requests_lock);
2445 	spin_lock_init(&reg_pending_beacons_lock);
2446 
2447 	reg_regdb_size_check();
2448 
2449 	cfg80211_regdomain = cfg80211_world_regdom;
2450 
2451 	user_alpha2[0] = '9';
2452 	user_alpha2[1] = '7';
2453 
2454 	/* We always try to get an update for the static regdomain */
2455 	err = regulatory_hint_core(cfg80211_regdomain->alpha2);
2456 	if (err) {
2457 		if (err == -ENOMEM)
2458 			return err;
2459 		/*
2460 		 * N.B. kobject_uevent_env() can fail mainly for when we're out
2461 		 * memory which is handled and propagated appropriately above
2462 		 * but it can also fail during a netlink_broadcast() or during
2463 		 * early boot for call_usermodehelper(). For now treat these
2464 		 * errors as non-fatal.
2465 		 */
2466 		pr_err("kobject_uevent_env() was unable to call CRDA during init\n");
2467 #ifdef CONFIG_CFG80211_REG_DEBUG
2468 		/* We want to find out exactly why when debugging */
2469 		WARN_ON(err);
2470 #endif
2471 	}
2472 
2473 	/*
2474 	 * Finally, if the user set the module parameter treat it
2475 	 * as a user hint.
2476 	 */
2477 	if (!is_world_regdom(ieee80211_regdom))
2478 		regulatory_hint_user(ieee80211_regdom,
2479 				     NL80211_USER_REG_HINT_USER);
2480 
2481 	return 0;
2482 }
2483 
2484 void /* __init_or_exit */ regulatory_exit(void)
2485 {
2486 	struct regulatory_request *reg_request, *tmp;
2487 	struct reg_beacon *reg_beacon, *btmp;
2488 
2489 	cancel_work_sync(&reg_work);
2490 	cancel_delayed_work_sync(&reg_timeout);
2491 
2492 	mutex_lock(&cfg80211_mutex);
2493 	mutex_lock(&reg_mutex);
2494 
2495 	reset_regdomains(true);
2496 
2497 	dev_set_uevent_suppress(&reg_pdev->dev, true);
2498 
2499 	platform_device_unregister(reg_pdev);
2500 
2501 	spin_lock_bh(&reg_pending_beacons_lock);
2502 	if (!list_empty(&reg_pending_beacons)) {
2503 		list_for_each_entry_safe(reg_beacon, btmp,
2504 					 &reg_pending_beacons, list) {
2505 			list_del(&reg_beacon->list);
2506 			kfree(reg_beacon);
2507 		}
2508 	}
2509 	spin_unlock_bh(&reg_pending_beacons_lock);
2510 
2511 	if (!list_empty(&reg_beacon_list)) {
2512 		list_for_each_entry_safe(reg_beacon, btmp,
2513 					 &reg_beacon_list, list) {
2514 			list_del(&reg_beacon->list);
2515 			kfree(reg_beacon);
2516 		}
2517 	}
2518 
2519 	spin_lock(&reg_requests_lock);
2520 	if (!list_empty(&reg_requests_list)) {
2521 		list_for_each_entry_safe(reg_request, tmp,
2522 					 &reg_requests_list, list) {
2523 			list_del(&reg_request->list);
2524 			kfree(reg_request);
2525 		}
2526 	}
2527 	spin_unlock(&reg_requests_lock);
2528 
2529 	mutex_unlock(&reg_mutex);
2530 	mutex_unlock(&cfg80211_mutex);
2531 }
2532