xref: /linux/net/wireless/reg.c (revision ac6a0cf6716bb46813d0161024c66c2af66e53d1)
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 #include <linux/kernel.h>
36 #include <linux/list.h>
37 #include <linux/random.h>
38 #include <linux/nl80211.h>
39 #include <linux/platform_device.h>
40 #include <net/cfg80211.h>
41 #include "core.h"
42 #include "reg.h"
43 #include "nl80211.h"
44 
45 /* Receipt of information from last regulatory request */
46 static struct regulatory_request *last_request;
47 
48 /* To trigger userspace events */
49 static struct platform_device *reg_pdev;
50 
51 /*
52  * Central wireless core regulatory domains, we only need two,
53  * the current one and a world regulatory domain in case we have no
54  * information to give us an alpha2
55  */
56 const struct ieee80211_regdomain *cfg80211_regdomain;
57 
58 /*
59  * We use this as a place for the rd structure built from the
60  * last parsed country IE to rest until CRDA gets back to us with
61  * what it thinks should apply for the same country
62  */
63 static const struct ieee80211_regdomain *country_ie_regdomain;
64 
65 /* Used to queue up regulatory hints */
66 static LIST_HEAD(reg_requests_list);
67 static spinlock_t reg_requests_lock;
68 
69 /* Used to queue up beacon hints for review */
70 static LIST_HEAD(reg_pending_beacons);
71 static spinlock_t reg_pending_beacons_lock;
72 
73 /* Used to keep track of processed beacon hints */
74 static LIST_HEAD(reg_beacon_list);
75 
76 struct reg_beacon {
77 	struct list_head list;
78 	struct ieee80211_channel chan;
79 };
80 
81 /* We keep a static world regulatory domain in case of the absence of CRDA */
82 static const struct ieee80211_regdomain world_regdom = {
83 	.n_reg_rules = 5,
84 	.alpha2 =  "00",
85 	.reg_rules = {
86 		/* IEEE 802.11b/g, channels 1..11 */
87 		REG_RULE(2412-10, 2462+10, 40, 6, 20, 0),
88 		/* IEEE 802.11b/g, channels 12..13. No HT40
89 		 * channel fits here. */
90 		REG_RULE(2467-10, 2472+10, 20, 6, 20,
91 			NL80211_RRF_PASSIVE_SCAN |
92 			NL80211_RRF_NO_IBSS),
93 		/* IEEE 802.11 channel 14 - Only JP enables
94 		 * this and for 802.11b only */
95 		REG_RULE(2484-10, 2484+10, 20, 6, 20,
96 			NL80211_RRF_PASSIVE_SCAN |
97 			NL80211_RRF_NO_IBSS |
98 			NL80211_RRF_NO_OFDM),
99 		/* IEEE 802.11a, channel 36..48 */
100 		REG_RULE(5180-10, 5240+10, 40, 6, 20,
101                         NL80211_RRF_PASSIVE_SCAN |
102                         NL80211_RRF_NO_IBSS),
103 
104 		/* NB: 5260 MHz - 5700 MHz requies DFS */
105 
106 		/* IEEE 802.11a, channel 149..165 */
107 		REG_RULE(5745-10, 5825+10, 40, 6, 20,
108 			NL80211_RRF_PASSIVE_SCAN |
109 			NL80211_RRF_NO_IBSS),
110 	}
111 };
112 
113 static const struct ieee80211_regdomain *cfg80211_world_regdom =
114 	&world_regdom;
115 
116 #ifdef CONFIG_WIRELESS_OLD_REGULATORY
117 static char *ieee80211_regdom = "US";
118 #else
119 static char *ieee80211_regdom = "00";
120 #endif
121 
122 module_param(ieee80211_regdom, charp, 0444);
123 MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain code");
124 
125 #ifdef CONFIG_WIRELESS_OLD_REGULATORY
126 /*
127  * We assume 40 MHz bandwidth for the old regulatory work.
128  * We make emphasis we are using the exact same frequencies
129  * as before
130  */
131 
132 static const struct ieee80211_regdomain us_regdom = {
133 	.n_reg_rules = 6,
134 	.alpha2 =  "US",
135 	.reg_rules = {
136 		/* IEEE 802.11b/g, channels 1..11 */
137 		REG_RULE(2412-10, 2462+10, 40, 6, 27, 0),
138 		/* IEEE 802.11a, channel 36 */
139 		REG_RULE(5180-10, 5180+10, 40, 6, 23, 0),
140 		/* IEEE 802.11a, channel 40 */
141 		REG_RULE(5200-10, 5200+10, 40, 6, 23, 0),
142 		/* IEEE 802.11a, channel 44 */
143 		REG_RULE(5220-10, 5220+10, 40, 6, 23, 0),
144 		/* IEEE 802.11a, channels 48..64 */
145 		REG_RULE(5240-10, 5320+10, 40, 6, 23, 0),
146 		/* IEEE 802.11a, channels 149..165, outdoor */
147 		REG_RULE(5745-10, 5825+10, 40, 6, 30, 0),
148 	}
149 };
150 
151 static const struct ieee80211_regdomain jp_regdom = {
152 	.n_reg_rules = 3,
153 	.alpha2 =  "JP",
154 	.reg_rules = {
155 		/* IEEE 802.11b/g, channels 1..14 */
156 		REG_RULE(2412-10, 2484+10, 40, 6, 20, 0),
157 		/* IEEE 802.11a, channels 34..48 */
158 		REG_RULE(5170-10, 5240+10, 40, 6, 20,
159 			NL80211_RRF_PASSIVE_SCAN),
160 		/* IEEE 802.11a, channels 52..64 */
161 		REG_RULE(5260-10, 5320+10, 40, 6, 20,
162 			NL80211_RRF_NO_IBSS |
163 			NL80211_RRF_DFS),
164 	}
165 };
166 
167 static const struct ieee80211_regdomain eu_regdom = {
168 	.n_reg_rules = 6,
169 	/*
170 	 * This alpha2 is bogus, we leave it here just for stupid
171 	 * backward compatibility
172 	 */
173 	.alpha2 =  "EU",
174 	.reg_rules = {
175 		/* IEEE 802.11b/g, channels 1..13 */
176 		REG_RULE(2412-10, 2472+10, 40, 6, 20, 0),
177 		/* IEEE 802.11a, channel 36 */
178 		REG_RULE(5180-10, 5180+10, 40, 6, 23,
179 			NL80211_RRF_PASSIVE_SCAN),
180 		/* IEEE 802.11a, channel 40 */
181 		REG_RULE(5200-10, 5200+10, 40, 6, 23,
182 			NL80211_RRF_PASSIVE_SCAN),
183 		/* IEEE 802.11a, channel 44 */
184 		REG_RULE(5220-10, 5220+10, 40, 6, 23,
185 			NL80211_RRF_PASSIVE_SCAN),
186 		/* IEEE 802.11a, channels 48..64 */
187 		REG_RULE(5240-10, 5320+10, 40, 6, 20,
188 			NL80211_RRF_NO_IBSS |
189 			NL80211_RRF_DFS),
190 		/* IEEE 802.11a, channels 100..140 */
191 		REG_RULE(5500-10, 5700+10, 40, 6, 30,
192 			NL80211_RRF_NO_IBSS |
193 			NL80211_RRF_DFS),
194 	}
195 };
196 
197 static const struct ieee80211_regdomain *static_regdom(char *alpha2)
198 {
199 	if (alpha2[0] == 'U' && alpha2[1] == 'S')
200 		return &us_regdom;
201 	if (alpha2[0] == 'J' && alpha2[1] == 'P')
202 		return &jp_regdom;
203 	if (alpha2[0] == 'E' && alpha2[1] == 'U')
204 		return &eu_regdom;
205 	/* Default, as per the old rules */
206 	return &us_regdom;
207 }
208 
209 static bool is_old_static_regdom(const struct ieee80211_regdomain *rd)
210 {
211 	if (rd == &us_regdom || rd == &jp_regdom || rd == &eu_regdom)
212 		return true;
213 	return false;
214 }
215 #else
216 static inline bool is_old_static_regdom(const struct ieee80211_regdomain *rd)
217 {
218 	return false;
219 }
220 #endif
221 
222 static void reset_regdomains(void)
223 {
224 	/* avoid freeing static information or freeing something twice */
225 	if (cfg80211_regdomain == cfg80211_world_regdom)
226 		cfg80211_regdomain = NULL;
227 	if (cfg80211_world_regdom == &world_regdom)
228 		cfg80211_world_regdom = NULL;
229 	if (cfg80211_regdomain == &world_regdom)
230 		cfg80211_regdomain = NULL;
231 	if (is_old_static_regdom(cfg80211_regdomain))
232 		cfg80211_regdomain = NULL;
233 
234 	kfree(cfg80211_regdomain);
235 	kfree(cfg80211_world_regdom);
236 
237 	cfg80211_world_regdom = &world_regdom;
238 	cfg80211_regdomain = NULL;
239 }
240 
241 /*
242  * Dynamic world regulatory domain requested by the wireless
243  * core upon initialization
244  */
245 static void update_world_regdomain(const struct ieee80211_regdomain *rd)
246 {
247 	BUG_ON(!last_request);
248 
249 	reset_regdomains();
250 
251 	cfg80211_world_regdom = rd;
252 	cfg80211_regdomain = rd;
253 }
254 
255 bool is_world_regdom(const char *alpha2)
256 {
257 	if (!alpha2)
258 		return false;
259 	if (alpha2[0] == '0' && alpha2[1] == '0')
260 		return true;
261 	return false;
262 }
263 
264 static bool is_alpha2_set(const char *alpha2)
265 {
266 	if (!alpha2)
267 		return false;
268 	if (alpha2[0] != 0 && alpha2[1] != 0)
269 		return true;
270 	return false;
271 }
272 
273 static bool is_alpha_upper(char letter)
274 {
275 	/* ASCII A - Z */
276 	if (letter >= 65 && letter <= 90)
277 		return true;
278 	return false;
279 }
280 
281 static bool is_unknown_alpha2(const char *alpha2)
282 {
283 	if (!alpha2)
284 		return false;
285 	/*
286 	 * Special case where regulatory domain was built by driver
287 	 * but a specific alpha2 cannot be determined
288 	 */
289 	if (alpha2[0] == '9' && alpha2[1] == '9')
290 		return true;
291 	return false;
292 }
293 
294 static bool is_intersected_alpha2(const char *alpha2)
295 {
296 	if (!alpha2)
297 		return false;
298 	/*
299 	 * Special case where regulatory domain is the
300 	 * result of an intersection between two regulatory domain
301 	 * structures
302 	 */
303 	if (alpha2[0] == '9' && alpha2[1] == '8')
304 		return true;
305 	return false;
306 }
307 
308 static bool is_an_alpha2(const char *alpha2)
309 {
310 	if (!alpha2)
311 		return false;
312 	if (is_alpha_upper(alpha2[0]) && is_alpha_upper(alpha2[1]))
313 		return true;
314 	return false;
315 }
316 
317 static bool alpha2_equal(const char *alpha2_x, const char *alpha2_y)
318 {
319 	if (!alpha2_x || !alpha2_y)
320 		return false;
321 	if (alpha2_x[0] == alpha2_y[0] &&
322 		alpha2_x[1] == alpha2_y[1])
323 		return true;
324 	return false;
325 }
326 
327 static bool regdom_changes(const char *alpha2)
328 {
329 	assert_cfg80211_lock();
330 
331 	if (!cfg80211_regdomain)
332 		return true;
333 	if (alpha2_equal(cfg80211_regdomain->alpha2, alpha2))
334 		return false;
335 	return true;
336 }
337 
338 /**
339  * country_ie_integrity_changes - tells us if the country IE has changed
340  * @checksum: checksum of country IE of fields we are interested in
341  *
342  * If the country IE has not changed you can ignore it safely. This is
343  * useful to determine if two devices are seeing two different country IEs
344  * even on the same alpha2. Note that this will return false if no IE has
345  * been set on the wireless core yet.
346  */
347 static bool country_ie_integrity_changes(u32 checksum)
348 {
349 	/* If no IE has been set then the checksum doesn't change */
350 	if (unlikely(!last_request->country_ie_checksum))
351 		return false;
352 	if (unlikely(last_request->country_ie_checksum != checksum))
353 		return true;
354 	return false;
355 }
356 
357 /*
358  * This lets us keep regulatory code which is updated on a regulatory
359  * basis in userspace.
360  */
361 static int call_crda(const char *alpha2)
362 {
363 	char country_env[9 + 2] = "COUNTRY=";
364 	char *envp[] = {
365 		country_env,
366 		NULL
367 	};
368 
369 	if (!is_world_regdom((char *) alpha2))
370 		printk(KERN_INFO "cfg80211: Calling CRDA for country: %c%c\n",
371 			alpha2[0], alpha2[1]);
372 	else
373 		printk(KERN_INFO "cfg80211: Calling CRDA to update world "
374 			"regulatory domain\n");
375 
376 	country_env[8] = alpha2[0];
377 	country_env[9] = alpha2[1];
378 
379 	return kobject_uevent_env(&reg_pdev->dev.kobj, KOBJ_CHANGE, envp);
380 }
381 
382 /* Used by nl80211 before kmalloc'ing our regulatory domain */
383 bool reg_is_valid_request(const char *alpha2)
384 {
385 	assert_cfg80211_lock();
386 
387 	if (!last_request)
388 		return false;
389 
390 	return alpha2_equal(last_request->alpha2, alpha2);
391 }
392 
393 /* Sanity check on a regulatory rule */
394 static bool is_valid_reg_rule(const struct ieee80211_reg_rule *rule)
395 {
396 	const struct ieee80211_freq_range *freq_range = &rule->freq_range;
397 	u32 freq_diff;
398 
399 	if (freq_range->start_freq_khz <= 0 || freq_range->end_freq_khz <= 0)
400 		return false;
401 
402 	if (freq_range->start_freq_khz > freq_range->end_freq_khz)
403 		return false;
404 
405 	freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
406 
407 	if (freq_range->end_freq_khz <= freq_range->start_freq_khz ||
408 			freq_range->max_bandwidth_khz > freq_diff)
409 		return false;
410 
411 	return true;
412 }
413 
414 static bool is_valid_rd(const struct ieee80211_regdomain *rd)
415 {
416 	const struct ieee80211_reg_rule *reg_rule = NULL;
417 	unsigned int i;
418 
419 	if (!rd->n_reg_rules)
420 		return false;
421 
422 	if (WARN_ON(rd->n_reg_rules > NL80211_MAX_SUPP_REG_RULES))
423 		return false;
424 
425 	for (i = 0; i < rd->n_reg_rules; i++) {
426 		reg_rule = &rd->reg_rules[i];
427 		if (!is_valid_reg_rule(reg_rule))
428 			return false;
429 	}
430 
431 	return true;
432 }
433 
434 static bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_range,
435 			    u32 center_freq_khz,
436 			    u32 bw_khz)
437 {
438 	u32 start_freq_khz, end_freq_khz;
439 
440 	start_freq_khz = center_freq_khz - (bw_khz/2);
441 	end_freq_khz = center_freq_khz + (bw_khz/2);
442 
443 	if (start_freq_khz >= freq_range->start_freq_khz &&
444 	    end_freq_khz <= freq_range->end_freq_khz)
445 		return true;
446 
447 	return false;
448 }
449 
450 /**
451  * freq_in_rule_band - tells us if a frequency is in a frequency band
452  * @freq_range: frequency rule we want to query
453  * @freq_khz: frequency we are inquiring about
454  *
455  * This lets us know if a specific frequency rule is or is not relevant to
456  * a specific frequency's band. Bands are device specific and artificial
457  * definitions (the "2.4 GHz band" and the "5 GHz band"), however it is
458  * safe for now to assume that a frequency rule should not be part of a
459  * frequency's band if the start freq or end freq are off by more than 2 GHz.
460  * This resolution can be lowered and should be considered as we add
461  * regulatory rule support for other "bands".
462  **/
463 static bool freq_in_rule_band(const struct ieee80211_freq_range *freq_range,
464 	u32 freq_khz)
465 {
466 #define ONE_GHZ_IN_KHZ	1000000
467 	if (abs(freq_khz - freq_range->start_freq_khz) <= (2 * ONE_GHZ_IN_KHZ))
468 		return true;
469 	if (abs(freq_khz - freq_range->end_freq_khz) <= (2 * ONE_GHZ_IN_KHZ))
470 		return true;
471 	return false;
472 #undef ONE_GHZ_IN_KHZ
473 }
474 
475 /*
476  * Converts a country IE to a regulatory domain. A regulatory domain
477  * structure has a lot of information which the IE doesn't yet have,
478  * so for the other values we use upper max values as we will intersect
479  * with our userspace regulatory agent to get lower bounds.
480  */
481 static struct ieee80211_regdomain *country_ie_2_rd(
482 				u8 *country_ie,
483 				u8 country_ie_len,
484 				u32 *checksum)
485 {
486 	struct ieee80211_regdomain *rd = NULL;
487 	unsigned int i = 0;
488 	char alpha2[2];
489 	u32 flags = 0;
490 	u32 num_rules = 0, size_of_regd = 0;
491 	u8 *triplets_start = NULL;
492 	u8 len_at_triplet = 0;
493 	/* the last channel we have registered in a subband (triplet) */
494 	int last_sub_max_channel = 0;
495 
496 	*checksum = 0xDEADBEEF;
497 
498 	/* Country IE requirements */
499 	BUG_ON(country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN ||
500 		country_ie_len & 0x01);
501 
502 	alpha2[0] = country_ie[0];
503 	alpha2[1] = country_ie[1];
504 
505 	/*
506 	 * Third octet can be:
507 	 *    'I' - Indoor
508 	 *    'O' - Outdoor
509 	 *
510 	 *  anything else we assume is no restrictions
511 	 */
512 	if (country_ie[2] == 'I')
513 		flags = NL80211_RRF_NO_OUTDOOR;
514 	else if (country_ie[2] == 'O')
515 		flags = NL80211_RRF_NO_INDOOR;
516 
517 	country_ie += 3;
518 	country_ie_len -= 3;
519 
520 	triplets_start = country_ie;
521 	len_at_triplet = country_ie_len;
522 
523 	*checksum ^= ((flags ^ alpha2[0] ^ alpha2[1]) << 8);
524 
525 	/*
526 	 * We need to build a reg rule for each triplet, but first we must
527 	 * calculate the number of reg rules we will need. We will need one
528 	 * for each channel subband
529 	 */
530 	while (country_ie_len >= 3) {
531 		int end_channel = 0;
532 		struct ieee80211_country_ie_triplet *triplet =
533 			(struct ieee80211_country_ie_triplet *) country_ie;
534 		int cur_sub_max_channel = 0, cur_channel = 0;
535 
536 		if (triplet->ext.reg_extension_id >=
537 				IEEE80211_COUNTRY_EXTENSION_ID) {
538 			country_ie += 3;
539 			country_ie_len -= 3;
540 			continue;
541 		}
542 
543 		/* 2 GHz */
544 		if (triplet->chans.first_channel <= 14)
545 			end_channel = triplet->chans.first_channel +
546 				triplet->chans.num_channels;
547 		else
548 			/*
549 			 * 5 GHz -- For example in country IEs if the first
550 			 * channel given is 36 and the number of channels is 4
551 			 * then the individual channel numbers defined for the
552 			 * 5 GHz PHY by these parameters are: 36, 40, 44, and 48
553 			 * and not 36, 37, 38, 39.
554 			 *
555 			 * See: http://tinyurl.com/11d-clarification
556 			 */
557 			end_channel =  triplet->chans.first_channel +
558 				(4 * (triplet->chans.num_channels - 1));
559 
560 		cur_channel = triplet->chans.first_channel;
561 		cur_sub_max_channel = end_channel;
562 
563 		/* Basic sanity check */
564 		if (cur_sub_max_channel < cur_channel)
565 			return NULL;
566 
567 		/*
568 		 * Do not allow overlapping channels. Also channels
569 		 * passed in each subband must be monotonically
570 		 * increasing
571 		 */
572 		if (last_sub_max_channel) {
573 			if (cur_channel <= last_sub_max_channel)
574 				return NULL;
575 			if (cur_sub_max_channel <= last_sub_max_channel)
576 				return NULL;
577 		}
578 
579 		/*
580 		 * When dot11RegulatoryClassesRequired is supported
581 		 * we can throw ext triplets as part of this soup,
582 		 * for now we don't care when those change as we
583 		 * don't support them
584 		 */
585 		*checksum ^= ((cur_channel ^ cur_sub_max_channel) << 8) |
586 		  ((cur_sub_max_channel ^ cur_sub_max_channel) << 16) |
587 		  ((triplet->chans.max_power ^ cur_sub_max_channel) << 24);
588 
589 		last_sub_max_channel = cur_sub_max_channel;
590 
591 		country_ie += 3;
592 		country_ie_len -= 3;
593 		num_rules++;
594 
595 		/*
596 		 * Note: this is not a IEEE requirement but
597 		 * simply a memory requirement
598 		 */
599 		if (num_rules > NL80211_MAX_SUPP_REG_RULES)
600 			return NULL;
601 	}
602 
603 	country_ie = triplets_start;
604 	country_ie_len = len_at_triplet;
605 
606 	size_of_regd = sizeof(struct ieee80211_regdomain) +
607 		(num_rules * sizeof(struct ieee80211_reg_rule));
608 
609 	rd = kzalloc(size_of_regd, GFP_KERNEL);
610 	if (!rd)
611 		return NULL;
612 
613 	rd->n_reg_rules = num_rules;
614 	rd->alpha2[0] = alpha2[0];
615 	rd->alpha2[1] = alpha2[1];
616 
617 	/* This time around we fill in the rd */
618 	while (country_ie_len >= 3) {
619 		int end_channel = 0;
620 		struct ieee80211_country_ie_triplet *triplet =
621 			(struct ieee80211_country_ie_triplet *) country_ie;
622 		struct ieee80211_reg_rule *reg_rule = NULL;
623 		struct ieee80211_freq_range *freq_range = NULL;
624 		struct ieee80211_power_rule *power_rule = NULL;
625 
626 		/*
627 		 * Must parse if dot11RegulatoryClassesRequired is true,
628 		 * we don't support this yet
629 		 */
630 		if (triplet->ext.reg_extension_id >=
631 				IEEE80211_COUNTRY_EXTENSION_ID) {
632 			country_ie += 3;
633 			country_ie_len -= 3;
634 			continue;
635 		}
636 
637 		reg_rule = &rd->reg_rules[i];
638 		freq_range = &reg_rule->freq_range;
639 		power_rule = &reg_rule->power_rule;
640 
641 		reg_rule->flags = flags;
642 
643 		/* 2 GHz */
644 		if (triplet->chans.first_channel <= 14)
645 			end_channel = triplet->chans.first_channel +
646 				triplet->chans.num_channels;
647 		else
648 			end_channel =  triplet->chans.first_channel +
649 				(4 * (triplet->chans.num_channels - 1));
650 
651 		/*
652 		 * The +10 is since the regulatory domain expects
653 		 * the actual band edge, not the center of freq for
654 		 * its start and end freqs, assuming 20 MHz bandwidth on
655 		 * the channels passed
656 		 */
657 		freq_range->start_freq_khz =
658 			MHZ_TO_KHZ(ieee80211_channel_to_frequency(
659 				triplet->chans.first_channel) - 10);
660 		freq_range->end_freq_khz =
661 			MHZ_TO_KHZ(ieee80211_channel_to_frequency(
662 				end_channel) + 10);
663 
664 		/*
665 		 * These are large arbitrary values we use to intersect later.
666 		 * Increment this if we ever support >= 40 MHz channels
667 		 * in IEEE 802.11
668 		 */
669 		freq_range->max_bandwidth_khz = MHZ_TO_KHZ(40);
670 		power_rule->max_antenna_gain = DBI_TO_MBI(100);
671 		power_rule->max_eirp = DBM_TO_MBM(100);
672 
673 		country_ie += 3;
674 		country_ie_len -= 3;
675 		i++;
676 
677 		BUG_ON(i > NL80211_MAX_SUPP_REG_RULES);
678 	}
679 
680 	return rd;
681 }
682 
683 
684 /*
685  * Helper for regdom_intersect(), this does the real
686  * mathematical intersection fun
687  */
688 static int reg_rules_intersect(
689 	const struct ieee80211_reg_rule *rule1,
690 	const struct ieee80211_reg_rule *rule2,
691 	struct ieee80211_reg_rule *intersected_rule)
692 {
693 	const struct ieee80211_freq_range *freq_range1, *freq_range2;
694 	struct ieee80211_freq_range *freq_range;
695 	const struct ieee80211_power_rule *power_rule1, *power_rule2;
696 	struct ieee80211_power_rule *power_rule;
697 	u32 freq_diff;
698 
699 	freq_range1 = &rule1->freq_range;
700 	freq_range2 = &rule2->freq_range;
701 	freq_range = &intersected_rule->freq_range;
702 
703 	power_rule1 = &rule1->power_rule;
704 	power_rule2 = &rule2->power_rule;
705 	power_rule = &intersected_rule->power_rule;
706 
707 	freq_range->start_freq_khz = max(freq_range1->start_freq_khz,
708 		freq_range2->start_freq_khz);
709 	freq_range->end_freq_khz = min(freq_range1->end_freq_khz,
710 		freq_range2->end_freq_khz);
711 	freq_range->max_bandwidth_khz = min(freq_range1->max_bandwidth_khz,
712 		freq_range2->max_bandwidth_khz);
713 
714 	freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
715 	if (freq_range->max_bandwidth_khz > freq_diff)
716 		freq_range->max_bandwidth_khz = freq_diff;
717 
718 	power_rule->max_eirp = min(power_rule1->max_eirp,
719 		power_rule2->max_eirp);
720 	power_rule->max_antenna_gain = min(power_rule1->max_antenna_gain,
721 		power_rule2->max_antenna_gain);
722 
723 	intersected_rule->flags = (rule1->flags | rule2->flags);
724 
725 	if (!is_valid_reg_rule(intersected_rule))
726 		return -EINVAL;
727 
728 	return 0;
729 }
730 
731 /**
732  * regdom_intersect - do the intersection between two regulatory domains
733  * @rd1: first regulatory domain
734  * @rd2: second regulatory domain
735  *
736  * Use this function to get the intersection between two regulatory domains.
737  * Once completed we will mark the alpha2 for the rd as intersected, "98",
738  * as no one single alpha2 can represent this regulatory domain.
739  *
740  * Returns a pointer to the regulatory domain structure which will hold the
741  * resulting intersection of rules between rd1 and rd2. We will
742  * kzalloc() this structure for you.
743  */
744 static struct ieee80211_regdomain *regdom_intersect(
745 	const struct ieee80211_regdomain *rd1,
746 	const struct ieee80211_regdomain *rd2)
747 {
748 	int r, size_of_regd;
749 	unsigned int x, y;
750 	unsigned int num_rules = 0, rule_idx = 0;
751 	const struct ieee80211_reg_rule *rule1, *rule2;
752 	struct ieee80211_reg_rule *intersected_rule;
753 	struct ieee80211_regdomain *rd;
754 	/* This is just a dummy holder to help us count */
755 	struct ieee80211_reg_rule irule;
756 
757 	/* Uses the stack temporarily for counter arithmetic */
758 	intersected_rule = &irule;
759 
760 	memset(intersected_rule, 0, sizeof(struct ieee80211_reg_rule));
761 
762 	if (!rd1 || !rd2)
763 		return NULL;
764 
765 	/*
766 	 * First we get a count of the rules we'll need, then we actually
767 	 * build them. This is to so we can malloc() and free() a
768 	 * regdomain once. The reason we use reg_rules_intersect() here
769 	 * is it will return -EINVAL if the rule computed makes no sense.
770 	 * All rules that do check out OK are valid.
771 	 */
772 
773 	for (x = 0; x < rd1->n_reg_rules; x++) {
774 		rule1 = &rd1->reg_rules[x];
775 		for (y = 0; y < rd2->n_reg_rules; y++) {
776 			rule2 = &rd2->reg_rules[y];
777 			if (!reg_rules_intersect(rule1, rule2,
778 					intersected_rule))
779 				num_rules++;
780 			memset(intersected_rule, 0,
781 					sizeof(struct ieee80211_reg_rule));
782 		}
783 	}
784 
785 	if (!num_rules)
786 		return NULL;
787 
788 	size_of_regd = sizeof(struct ieee80211_regdomain) +
789 		((num_rules + 1) * sizeof(struct ieee80211_reg_rule));
790 
791 	rd = kzalloc(size_of_regd, GFP_KERNEL);
792 	if (!rd)
793 		return NULL;
794 
795 	for (x = 0; x < rd1->n_reg_rules; x++) {
796 		rule1 = &rd1->reg_rules[x];
797 		for (y = 0; y < rd2->n_reg_rules; y++) {
798 			rule2 = &rd2->reg_rules[y];
799 			/*
800 			 * This time around instead of using the stack lets
801 			 * write to the target rule directly saving ourselves
802 			 * a memcpy()
803 			 */
804 			intersected_rule = &rd->reg_rules[rule_idx];
805 			r = reg_rules_intersect(rule1, rule2,
806 				intersected_rule);
807 			/*
808 			 * No need to memset here the intersected rule here as
809 			 * we're not using the stack anymore
810 			 */
811 			if (r)
812 				continue;
813 			rule_idx++;
814 		}
815 	}
816 
817 	if (rule_idx != num_rules) {
818 		kfree(rd);
819 		return NULL;
820 	}
821 
822 	rd->n_reg_rules = num_rules;
823 	rd->alpha2[0] = '9';
824 	rd->alpha2[1] = '8';
825 
826 	return rd;
827 }
828 
829 /*
830  * XXX: add support for the rest of enum nl80211_reg_rule_flags, we may
831  * want to just have the channel structure use these
832  */
833 static u32 map_regdom_flags(u32 rd_flags)
834 {
835 	u32 channel_flags = 0;
836 	if (rd_flags & NL80211_RRF_PASSIVE_SCAN)
837 		channel_flags |= IEEE80211_CHAN_PASSIVE_SCAN;
838 	if (rd_flags & NL80211_RRF_NO_IBSS)
839 		channel_flags |= IEEE80211_CHAN_NO_IBSS;
840 	if (rd_flags & NL80211_RRF_DFS)
841 		channel_flags |= IEEE80211_CHAN_RADAR;
842 	return channel_flags;
843 }
844 
845 static int freq_reg_info_regd(struct wiphy *wiphy,
846 			      u32 center_freq,
847 			      u32 desired_bw_khz,
848 			      const struct ieee80211_reg_rule **reg_rule,
849 			      const struct ieee80211_regdomain *custom_regd)
850 {
851 	int i;
852 	bool band_rule_found = false;
853 	const struct ieee80211_regdomain *regd;
854 	bool bw_fits = false;
855 
856 	if (!desired_bw_khz)
857 		desired_bw_khz = MHZ_TO_KHZ(20);
858 
859 	regd = custom_regd ? custom_regd : cfg80211_regdomain;
860 
861 	/*
862 	 * Follow the driver's regulatory domain, if present, unless a country
863 	 * IE has been processed or a user wants to help complaince further
864 	 */
865 	if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
866 	    last_request->initiator != NL80211_REGDOM_SET_BY_USER &&
867 	    wiphy->regd)
868 		regd = wiphy->regd;
869 
870 	if (!regd)
871 		return -EINVAL;
872 
873 	for (i = 0; i < regd->n_reg_rules; i++) {
874 		const struct ieee80211_reg_rule *rr;
875 		const struct ieee80211_freq_range *fr = NULL;
876 		const struct ieee80211_power_rule *pr = NULL;
877 
878 		rr = &regd->reg_rules[i];
879 		fr = &rr->freq_range;
880 		pr = &rr->power_rule;
881 
882 		/*
883 		 * We only need to know if one frequency rule was
884 		 * was in center_freq's band, that's enough, so lets
885 		 * not overwrite it once found
886 		 */
887 		if (!band_rule_found)
888 			band_rule_found = freq_in_rule_band(fr, center_freq);
889 
890 		bw_fits = reg_does_bw_fit(fr,
891 					  center_freq,
892 					  desired_bw_khz);
893 
894 		if (band_rule_found && bw_fits) {
895 			*reg_rule = rr;
896 			return 0;
897 		}
898 	}
899 
900 	if (!band_rule_found)
901 		return -ERANGE;
902 
903 	return -EINVAL;
904 }
905 EXPORT_SYMBOL(freq_reg_info);
906 
907 int freq_reg_info(struct wiphy *wiphy,
908 		  u32 center_freq,
909 		  u32 desired_bw_khz,
910 		  const struct ieee80211_reg_rule **reg_rule)
911 {
912 	assert_cfg80211_lock();
913 	return freq_reg_info_regd(wiphy,
914 				  center_freq,
915 				  desired_bw_khz,
916 				  reg_rule,
917 				  NULL);
918 }
919 
920 /*
921  * Note that right now we assume the desired channel bandwidth
922  * is always 20 MHz for each individual channel (HT40 uses 20 MHz
923  * per channel, the primary and the extension channel). To support
924  * smaller custom bandwidths such as 5 MHz or 10 MHz we'll need a
925  * new ieee80211_channel.target_bw and re run the regulatory check
926  * on the wiphy with the target_bw specified. Then we can simply use
927  * that below for the desired_bw_khz below.
928  */
929 static void handle_channel(struct wiphy *wiphy, enum ieee80211_band band,
930 			   unsigned int chan_idx)
931 {
932 	int r;
933 	u32 flags, bw_flags = 0;
934 	u32 desired_bw_khz = MHZ_TO_KHZ(20);
935 	const struct ieee80211_reg_rule *reg_rule = NULL;
936 	const struct ieee80211_power_rule *power_rule = NULL;
937 	const struct ieee80211_freq_range *freq_range = NULL;
938 	struct ieee80211_supported_band *sband;
939 	struct ieee80211_channel *chan;
940 	struct wiphy *request_wiphy = NULL;
941 
942 	assert_cfg80211_lock();
943 
944 	request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
945 
946 	sband = wiphy->bands[band];
947 	BUG_ON(chan_idx >= sband->n_channels);
948 	chan = &sband->channels[chan_idx];
949 
950 	flags = chan->orig_flags;
951 
952 	r = freq_reg_info(wiphy,
953 			  MHZ_TO_KHZ(chan->center_freq),
954 			  desired_bw_khz,
955 			  &reg_rule);
956 
957 	if (r) {
958 		/*
959 		 * This means no regulatory rule was found in the country IE
960 		 * with a frequency range on the center_freq's band, since
961 		 * IEEE-802.11 allows for a country IE to have a subset of the
962 		 * regulatory information provided in a country we ignore
963 		 * disabling the channel unless at least one reg rule was
964 		 * found on the center_freq's band. For details see this
965 		 * clarification:
966 		 *
967 		 * http://tinyurl.com/11d-clarification
968 		 */
969 		if (r == -ERANGE &&
970 		    last_request->initiator ==
971 		    NL80211_REGDOM_SET_BY_COUNTRY_IE) {
972 #ifdef CONFIG_CFG80211_REG_DEBUG
973 			printk(KERN_DEBUG "cfg80211: Leaving channel %d MHz "
974 				"intact on %s - no rule found in band on "
975 				"Country IE\n",
976 				chan->center_freq, wiphy_name(wiphy));
977 #endif
978 		} else {
979 		/*
980 		 * In this case we know the country IE has at least one reg rule
981 		 * for the band so we respect its band definitions
982 		 */
983 #ifdef CONFIG_CFG80211_REG_DEBUG
984 			if (last_request->initiator ==
985 			    NL80211_REGDOM_SET_BY_COUNTRY_IE)
986 				printk(KERN_DEBUG "cfg80211: Disabling "
987 					"channel %d MHz on %s due to "
988 					"Country IE\n",
989 					chan->center_freq, wiphy_name(wiphy));
990 #endif
991 			flags |= IEEE80211_CHAN_DISABLED;
992 			chan->flags = flags;
993 		}
994 		return;
995 	}
996 
997 	power_rule = &reg_rule->power_rule;
998 	freq_range = &reg_rule->freq_range;
999 
1000 	if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
1001 		bw_flags = IEEE80211_CHAN_NO_HT40;
1002 
1003 	if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1004 	    request_wiphy && request_wiphy == wiphy &&
1005 	    request_wiphy->strict_regulatory) {
1006 		/*
1007 		 * This gaurantees the driver's requested regulatory domain
1008 		 * will always be used as a base for further regulatory
1009 		 * settings
1010 		 */
1011 		chan->flags = chan->orig_flags =
1012 			map_regdom_flags(reg_rule->flags) | bw_flags;
1013 		chan->max_antenna_gain = chan->orig_mag =
1014 			(int) MBI_TO_DBI(power_rule->max_antenna_gain);
1015 		chan->max_bandwidth = KHZ_TO_MHZ(desired_bw_khz);
1016 		chan->max_power = chan->orig_mpwr =
1017 			(int) MBM_TO_DBM(power_rule->max_eirp);
1018 		return;
1019 	}
1020 
1021 	chan->flags = flags | bw_flags | map_regdom_flags(reg_rule->flags);
1022 	chan->max_antenna_gain = min(chan->orig_mag,
1023 		(int) MBI_TO_DBI(power_rule->max_antenna_gain));
1024 	chan->max_bandwidth = KHZ_TO_MHZ(desired_bw_khz);
1025 	if (chan->orig_mpwr)
1026 		chan->max_power = min(chan->orig_mpwr,
1027 			(int) MBM_TO_DBM(power_rule->max_eirp));
1028 	else
1029 		chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
1030 }
1031 
1032 static void handle_band(struct wiphy *wiphy, enum ieee80211_band band)
1033 {
1034 	unsigned int i;
1035 	struct ieee80211_supported_band *sband;
1036 
1037 	BUG_ON(!wiphy->bands[band]);
1038 	sband = wiphy->bands[band];
1039 
1040 	for (i = 0; i < sband->n_channels; i++)
1041 		handle_channel(wiphy, band, i);
1042 }
1043 
1044 static bool ignore_reg_update(struct wiphy *wiphy,
1045 			      enum nl80211_reg_initiator initiator)
1046 {
1047 	if (!last_request)
1048 		return true;
1049 	if (initiator == NL80211_REGDOM_SET_BY_CORE &&
1050 		  wiphy->custom_regulatory)
1051 		return true;
1052 	/*
1053 	 * wiphy->regd will be set once the device has its own
1054 	 * desired regulatory domain set
1055 	 */
1056 	if (wiphy->strict_regulatory && !wiphy->regd &&
1057 	    !is_world_regdom(last_request->alpha2))
1058 		return true;
1059 	return false;
1060 }
1061 
1062 static void update_all_wiphy_regulatory(enum nl80211_reg_initiator initiator)
1063 {
1064 	struct cfg80211_registered_device *drv;
1065 
1066 	list_for_each_entry(drv, &cfg80211_drv_list, list)
1067 		wiphy_update_regulatory(&drv->wiphy, initiator);
1068 }
1069 
1070 static void handle_reg_beacon(struct wiphy *wiphy,
1071 			      unsigned int chan_idx,
1072 			      struct reg_beacon *reg_beacon)
1073 {
1074 	struct ieee80211_supported_band *sband;
1075 	struct ieee80211_channel *chan;
1076 	bool channel_changed = false;
1077 	struct ieee80211_channel chan_before;
1078 
1079 	assert_cfg80211_lock();
1080 
1081 	sband = wiphy->bands[reg_beacon->chan.band];
1082 	chan = &sband->channels[chan_idx];
1083 
1084 	if (likely(chan->center_freq != reg_beacon->chan.center_freq))
1085 		return;
1086 
1087 	if (chan->beacon_found)
1088 		return;
1089 
1090 	chan->beacon_found = true;
1091 
1092 	if (wiphy->disable_beacon_hints)
1093 		return;
1094 
1095 	chan_before.center_freq = chan->center_freq;
1096 	chan_before.flags = chan->flags;
1097 
1098 	if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN) {
1099 		chan->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
1100 		channel_changed = true;
1101 	}
1102 
1103 	if (chan->flags & IEEE80211_CHAN_NO_IBSS) {
1104 		chan->flags &= ~IEEE80211_CHAN_NO_IBSS;
1105 		channel_changed = true;
1106 	}
1107 
1108 	if (channel_changed)
1109 		nl80211_send_beacon_hint_event(wiphy, &chan_before, chan);
1110 }
1111 
1112 /*
1113  * Called when a scan on a wiphy finds a beacon on
1114  * new channel
1115  */
1116 static void wiphy_update_new_beacon(struct wiphy *wiphy,
1117 				    struct reg_beacon *reg_beacon)
1118 {
1119 	unsigned int i;
1120 	struct ieee80211_supported_band *sband;
1121 
1122 	assert_cfg80211_lock();
1123 
1124 	if (!wiphy->bands[reg_beacon->chan.band])
1125 		return;
1126 
1127 	sband = wiphy->bands[reg_beacon->chan.band];
1128 
1129 	for (i = 0; i < sband->n_channels; i++)
1130 		handle_reg_beacon(wiphy, i, reg_beacon);
1131 }
1132 
1133 /*
1134  * Called upon reg changes or a new wiphy is added
1135  */
1136 static void wiphy_update_beacon_reg(struct wiphy *wiphy)
1137 {
1138 	unsigned int i;
1139 	struct ieee80211_supported_band *sband;
1140 	struct reg_beacon *reg_beacon;
1141 
1142 	assert_cfg80211_lock();
1143 
1144 	if (list_empty(&reg_beacon_list))
1145 		return;
1146 
1147 	list_for_each_entry(reg_beacon, &reg_beacon_list, list) {
1148 		if (!wiphy->bands[reg_beacon->chan.band])
1149 			continue;
1150 		sband = wiphy->bands[reg_beacon->chan.band];
1151 		for (i = 0; i < sband->n_channels; i++)
1152 			handle_reg_beacon(wiphy, i, reg_beacon);
1153 	}
1154 }
1155 
1156 static bool reg_is_world_roaming(struct wiphy *wiphy)
1157 {
1158 	if (is_world_regdom(cfg80211_regdomain->alpha2) ||
1159 	    (wiphy->regd && is_world_regdom(wiphy->regd->alpha2)))
1160 		return true;
1161 	if (last_request &&
1162 	    last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1163 	    wiphy->custom_regulatory)
1164 		return true;
1165 	return false;
1166 }
1167 
1168 /* Reap the advantages of previously found beacons */
1169 static void reg_process_beacons(struct wiphy *wiphy)
1170 {
1171 	/*
1172 	 * Means we are just firing up cfg80211, so no beacons would
1173 	 * have been processed yet.
1174 	 */
1175 	if (!last_request)
1176 		return;
1177 	if (!reg_is_world_roaming(wiphy))
1178 		return;
1179 	wiphy_update_beacon_reg(wiphy);
1180 }
1181 
1182 static bool is_ht40_not_allowed(struct ieee80211_channel *chan)
1183 {
1184 	if (!chan)
1185 		return true;
1186 	if (chan->flags & IEEE80211_CHAN_DISABLED)
1187 		return true;
1188 	/* This would happen when regulatory rules disallow HT40 completely */
1189 	if (IEEE80211_CHAN_NO_HT40 == (chan->flags & (IEEE80211_CHAN_NO_HT40)))
1190 		return true;
1191 	return false;
1192 }
1193 
1194 static void reg_process_ht_flags_channel(struct wiphy *wiphy,
1195 					 enum ieee80211_band band,
1196 					 unsigned int chan_idx)
1197 {
1198 	struct ieee80211_supported_band *sband;
1199 	struct ieee80211_channel *channel;
1200 	struct ieee80211_channel *channel_before = NULL, *channel_after = NULL;
1201 	unsigned int i;
1202 
1203 	assert_cfg80211_lock();
1204 
1205 	sband = wiphy->bands[band];
1206 	BUG_ON(chan_idx >= sband->n_channels);
1207 	channel = &sband->channels[chan_idx];
1208 
1209 	if (is_ht40_not_allowed(channel)) {
1210 		channel->flags |= IEEE80211_CHAN_NO_HT40;
1211 		return;
1212 	}
1213 
1214 	/*
1215 	 * We need to ensure the extension channels exist to
1216 	 * be able to use HT40- or HT40+, this finds them (or not)
1217 	 */
1218 	for (i = 0; i < sband->n_channels; i++) {
1219 		struct ieee80211_channel *c = &sband->channels[i];
1220 		if (c->center_freq == (channel->center_freq - 20))
1221 			channel_before = c;
1222 		if (c->center_freq == (channel->center_freq + 20))
1223 			channel_after = c;
1224 	}
1225 
1226 	/*
1227 	 * Please note that this assumes target bandwidth is 20 MHz,
1228 	 * if that ever changes we also need to change the below logic
1229 	 * to include that as well.
1230 	 */
1231 	if (is_ht40_not_allowed(channel_before))
1232 		channel->flags |= IEEE80211_CHAN_NO_HT40MINUS;
1233 	else
1234 		channel->flags &= ~IEEE80211_CHAN_NO_HT40MINUS;
1235 
1236 	if (is_ht40_not_allowed(channel_after))
1237 		channel->flags |= IEEE80211_CHAN_NO_HT40PLUS;
1238 	else
1239 		channel->flags &= ~IEEE80211_CHAN_NO_HT40PLUS;
1240 }
1241 
1242 static void reg_process_ht_flags_band(struct wiphy *wiphy,
1243 				      enum ieee80211_band band)
1244 {
1245 	unsigned int i;
1246 	struct ieee80211_supported_band *sband;
1247 
1248 	BUG_ON(!wiphy->bands[band]);
1249 	sband = wiphy->bands[band];
1250 
1251 	for (i = 0; i < sband->n_channels; i++)
1252 		reg_process_ht_flags_channel(wiphy, band, i);
1253 }
1254 
1255 static void reg_process_ht_flags(struct wiphy *wiphy)
1256 {
1257 	enum ieee80211_band band;
1258 
1259 	if (!wiphy)
1260 		return;
1261 
1262 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1263 		if (wiphy->bands[band])
1264 			reg_process_ht_flags_band(wiphy, band);
1265 	}
1266 
1267 }
1268 
1269 void wiphy_update_regulatory(struct wiphy *wiphy,
1270 			     enum nl80211_reg_initiator initiator)
1271 {
1272 	enum ieee80211_band band;
1273 
1274 	if (ignore_reg_update(wiphy, initiator))
1275 		goto out;
1276 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1277 		if (wiphy->bands[band])
1278 			handle_band(wiphy, band);
1279 	}
1280 out:
1281 	reg_process_beacons(wiphy);
1282 	reg_process_ht_flags(wiphy);
1283 	if (wiphy->reg_notifier)
1284 		wiphy->reg_notifier(wiphy, last_request);
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_cfg80211_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 		chan->flags = IEEE80211_CHAN_DISABLED;
1315 		return;
1316 	}
1317 
1318 	power_rule = &reg_rule->power_rule;
1319 	freq_range = &reg_rule->freq_range;
1320 
1321 	if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
1322 		bw_flags = IEEE80211_CHAN_NO_HT40;
1323 
1324 	chan->flags |= map_regdom_flags(reg_rule->flags) | bw_flags;
1325 	chan->max_antenna_gain = (int) MBI_TO_DBI(power_rule->max_antenna_gain);
1326 	chan->max_bandwidth = KHZ_TO_MHZ(desired_bw_khz);
1327 	chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
1328 }
1329 
1330 static void handle_band_custom(struct wiphy *wiphy, enum ieee80211_band band,
1331 			       const struct ieee80211_regdomain *regd)
1332 {
1333 	unsigned int i;
1334 	struct ieee80211_supported_band *sband;
1335 
1336 	BUG_ON(!wiphy->bands[band]);
1337 	sband = wiphy->bands[band];
1338 
1339 	for (i = 0; i < sband->n_channels; i++)
1340 		handle_channel_custom(wiphy, band, i, regd);
1341 }
1342 
1343 /* Used by drivers prior to wiphy registration */
1344 void wiphy_apply_custom_regulatory(struct wiphy *wiphy,
1345 				   const struct ieee80211_regdomain *regd)
1346 {
1347 	enum ieee80211_band band;
1348 	unsigned int bands_set = 0;
1349 
1350 	mutex_lock(&cfg80211_mutex);
1351 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1352 		if (!wiphy->bands[band])
1353 			continue;
1354 		handle_band_custom(wiphy, band, regd);
1355 		bands_set++;
1356 	}
1357 	mutex_unlock(&cfg80211_mutex);
1358 
1359 	/*
1360 	 * no point in calling this if it won't have any effect
1361 	 * on your device's supportd bands.
1362 	 */
1363 	WARN_ON(!bands_set);
1364 }
1365 EXPORT_SYMBOL(wiphy_apply_custom_regulatory);
1366 
1367 static int reg_copy_regd(const struct ieee80211_regdomain **dst_regd,
1368 			 const struct ieee80211_regdomain *src_regd)
1369 {
1370 	struct ieee80211_regdomain *regd;
1371 	int size_of_regd = 0;
1372 	unsigned int i;
1373 
1374 	size_of_regd = sizeof(struct ieee80211_regdomain) +
1375 	  ((src_regd->n_reg_rules + 1) * sizeof(struct ieee80211_reg_rule));
1376 
1377 	regd = kzalloc(size_of_regd, GFP_KERNEL);
1378 	if (!regd)
1379 		return -ENOMEM;
1380 
1381 	memcpy(regd, src_regd, sizeof(struct ieee80211_regdomain));
1382 
1383 	for (i = 0; i < src_regd->n_reg_rules; i++)
1384 		memcpy(&regd->reg_rules[i], &src_regd->reg_rules[i],
1385 			sizeof(struct ieee80211_reg_rule));
1386 
1387 	*dst_regd = regd;
1388 	return 0;
1389 }
1390 
1391 /*
1392  * Return value which can be used by ignore_request() to indicate
1393  * it has been determined we should intersect two regulatory domains
1394  */
1395 #define REG_INTERSECT	1
1396 
1397 /* This has the logic which determines when a new request
1398  * should be ignored. */
1399 static int ignore_request(struct wiphy *wiphy,
1400 			  struct regulatory_request *pending_request)
1401 {
1402 	struct wiphy *last_wiphy = NULL;
1403 
1404 	assert_cfg80211_lock();
1405 
1406 	/* All initial requests are respected */
1407 	if (!last_request)
1408 		return 0;
1409 
1410 	switch (pending_request->initiator) {
1411 	case NL80211_REGDOM_SET_BY_CORE:
1412 		return -EINVAL;
1413 	case NL80211_REGDOM_SET_BY_COUNTRY_IE:
1414 
1415 		last_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
1416 
1417 		if (unlikely(!is_an_alpha2(pending_request->alpha2)))
1418 			return -EINVAL;
1419 		if (last_request->initiator ==
1420 		    NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1421 			if (last_wiphy != wiphy) {
1422 				/*
1423 				 * Two cards with two APs claiming different
1424 				 * different Country IE alpha2s. We could
1425 				 * intersect them, but that seems unlikely
1426 				 * to be correct. Reject second one for now.
1427 				 */
1428 				if (regdom_changes(pending_request->alpha2))
1429 					return -EOPNOTSUPP;
1430 				return -EALREADY;
1431 			}
1432 			/*
1433 			 * Two consecutive Country IE hints on the same wiphy.
1434 			 * This should be picked up early by the driver/stack
1435 			 */
1436 			if (WARN_ON(regdom_changes(pending_request->alpha2)))
1437 				return 0;
1438 			return -EALREADY;
1439 		}
1440 		return REG_INTERSECT;
1441 	case NL80211_REGDOM_SET_BY_DRIVER:
1442 		if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE) {
1443 			if (is_old_static_regdom(cfg80211_regdomain))
1444 				return 0;
1445 			if (regdom_changes(pending_request->alpha2))
1446 				return 0;
1447 			return -EALREADY;
1448 		}
1449 
1450 		/*
1451 		 * This would happen if you unplug and plug your card
1452 		 * back in or if you add a new device for which the previously
1453 		 * loaded card also agrees on the regulatory domain.
1454 		 */
1455 		if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1456 		    !regdom_changes(pending_request->alpha2))
1457 			return -EALREADY;
1458 
1459 		return REG_INTERSECT;
1460 	case NL80211_REGDOM_SET_BY_USER:
1461 		if (last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE)
1462 			return REG_INTERSECT;
1463 		/*
1464 		 * If the user knows better the user should set the regdom
1465 		 * to their country before the IE is picked up
1466 		 */
1467 		if (last_request->initiator == NL80211_REGDOM_SET_BY_USER &&
1468 			  last_request->intersect)
1469 			return -EOPNOTSUPP;
1470 		/*
1471 		 * Process user requests only after previous user/driver/core
1472 		 * requests have been processed
1473 		 */
1474 		if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE ||
1475 		    last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER ||
1476 		    last_request->initiator == NL80211_REGDOM_SET_BY_USER) {
1477 			if (regdom_changes(last_request->alpha2))
1478 				return -EAGAIN;
1479 		}
1480 
1481 		if (!is_old_static_regdom(cfg80211_regdomain) &&
1482 		    !regdom_changes(pending_request->alpha2))
1483 			return -EALREADY;
1484 
1485 		return 0;
1486 	}
1487 
1488 	return -EINVAL;
1489 }
1490 
1491 /**
1492  * __regulatory_hint - hint to the wireless core a regulatory domain
1493  * @wiphy: if the hint comes from country information from an AP, this
1494  *	is required to be set to the wiphy that received the information
1495  * @pending_request: the regulatory request currently being processed
1496  *
1497  * The Wireless subsystem can use this function to hint to the wireless core
1498  * what it believes should be the current regulatory domain.
1499  *
1500  * Returns zero if all went fine, %-EALREADY if a regulatory domain had
1501  * already been set or other standard error codes.
1502  *
1503  * Caller must hold &cfg80211_mutex
1504  */
1505 static int __regulatory_hint(struct wiphy *wiphy,
1506 			     struct regulatory_request *pending_request)
1507 {
1508 	bool intersect = false;
1509 	int r = 0;
1510 
1511 	assert_cfg80211_lock();
1512 
1513 	r = ignore_request(wiphy, pending_request);
1514 
1515 	if (r == REG_INTERSECT) {
1516 		if (pending_request->initiator ==
1517 		    NL80211_REGDOM_SET_BY_DRIVER) {
1518 			r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1519 			if (r) {
1520 				kfree(pending_request);
1521 				return r;
1522 			}
1523 		}
1524 		intersect = true;
1525 	} else if (r) {
1526 		/*
1527 		 * If the regulatory domain being requested by the
1528 		 * driver has already been set just copy it to the
1529 		 * wiphy
1530 		 */
1531 		if (r == -EALREADY &&
1532 		    pending_request->initiator ==
1533 		    NL80211_REGDOM_SET_BY_DRIVER) {
1534 			r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1535 			if (r) {
1536 				kfree(pending_request);
1537 				return r;
1538 			}
1539 			r = -EALREADY;
1540 			goto new_request;
1541 		}
1542 		kfree(pending_request);
1543 		return r;
1544 	}
1545 
1546 new_request:
1547 	kfree(last_request);
1548 
1549 	last_request = pending_request;
1550 	last_request->intersect = intersect;
1551 
1552 	pending_request = NULL;
1553 
1554 	/* When r == REG_INTERSECT we do need to call CRDA */
1555 	if (r < 0) {
1556 		/*
1557 		 * Since CRDA will not be called in this case as we already
1558 		 * have applied the requested regulatory domain before we just
1559 		 * inform userspace we have processed the request
1560 		 */
1561 		if (r == -EALREADY)
1562 			nl80211_send_reg_change_event(last_request);
1563 		return r;
1564 	}
1565 
1566 	return call_crda(last_request->alpha2);
1567 }
1568 
1569 /* This processes *all* regulatory hints */
1570 static void reg_process_hint(struct regulatory_request *reg_request)
1571 {
1572 	int r = 0;
1573 	struct wiphy *wiphy = NULL;
1574 
1575 	BUG_ON(!reg_request->alpha2);
1576 
1577 	mutex_lock(&cfg80211_mutex);
1578 
1579 	if (wiphy_idx_valid(reg_request->wiphy_idx))
1580 		wiphy = wiphy_idx_to_wiphy(reg_request->wiphy_idx);
1581 
1582 	if (reg_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1583 	    !wiphy) {
1584 		kfree(reg_request);
1585 		goto out;
1586 	}
1587 
1588 	r = __regulatory_hint(wiphy, reg_request);
1589 	/* This is required so that the orig_* parameters are saved */
1590 	if (r == -EALREADY && wiphy && wiphy->strict_regulatory)
1591 		wiphy_update_regulatory(wiphy, reg_request->initiator);
1592 out:
1593 	mutex_unlock(&cfg80211_mutex);
1594 }
1595 
1596 /* Processes regulatory hints, this is all the NL80211_REGDOM_SET_BY_* */
1597 static void reg_process_pending_hints(void)
1598 	{
1599 	struct regulatory_request *reg_request;
1600 
1601 	spin_lock(&reg_requests_lock);
1602 	while (!list_empty(&reg_requests_list)) {
1603 		reg_request = list_first_entry(&reg_requests_list,
1604 					       struct regulatory_request,
1605 					       list);
1606 		list_del_init(&reg_request->list);
1607 
1608 		spin_unlock(&reg_requests_lock);
1609 		reg_process_hint(reg_request);
1610 		spin_lock(&reg_requests_lock);
1611 	}
1612 	spin_unlock(&reg_requests_lock);
1613 }
1614 
1615 /* Processes beacon hints -- this has nothing to do with country IEs */
1616 static void reg_process_pending_beacon_hints(void)
1617 {
1618 	struct cfg80211_registered_device *drv;
1619 	struct reg_beacon *pending_beacon, *tmp;
1620 
1621 	mutex_lock(&cfg80211_mutex);
1622 
1623 	/* This goes through the _pending_ beacon list */
1624 	spin_lock_bh(&reg_pending_beacons_lock);
1625 
1626 	if (list_empty(&reg_pending_beacons)) {
1627 		spin_unlock_bh(&reg_pending_beacons_lock);
1628 		goto out;
1629 	}
1630 
1631 	list_for_each_entry_safe(pending_beacon, tmp,
1632 				 &reg_pending_beacons, list) {
1633 
1634 		list_del_init(&pending_beacon->list);
1635 
1636 		/* Applies the beacon hint to current wiphys */
1637 		list_for_each_entry(drv, &cfg80211_drv_list, list)
1638 			wiphy_update_new_beacon(&drv->wiphy, pending_beacon);
1639 
1640 		/* Remembers the beacon hint for new wiphys or reg changes */
1641 		list_add_tail(&pending_beacon->list, &reg_beacon_list);
1642 	}
1643 
1644 	spin_unlock_bh(&reg_pending_beacons_lock);
1645 out:
1646 	mutex_unlock(&cfg80211_mutex);
1647 }
1648 
1649 static void reg_todo(struct work_struct *work)
1650 {
1651 	reg_process_pending_hints();
1652 	reg_process_pending_beacon_hints();
1653 }
1654 
1655 static DECLARE_WORK(reg_work, reg_todo);
1656 
1657 static void queue_regulatory_request(struct regulatory_request *request)
1658 {
1659 	spin_lock(&reg_requests_lock);
1660 	list_add_tail(&request->list, &reg_requests_list);
1661 	spin_unlock(&reg_requests_lock);
1662 
1663 	schedule_work(&reg_work);
1664 }
1665 
1666 /* Core regulatory hint -- happens once during cfg80211_init() */
1667 static int regulatory_hint_core(const char *alpha2)
1668 {
1669 	struct regulatory_request *request;
1670 
1671 	BUG_ON(last_request);
1672 
1673 	request = kzalloc(sizeof(struct regulatory_request),
1674 			  GFP_KERNEL);
1675 	if (!request)
1676 		return -ENOMEM;
1677 
1678 	request->alpha2[0] = alpha2[0];
1679 	request->alpha2[1] = alpha2[1];
1680 	request->initiator = NL80211_REGDOM_SET_BY_CORE;
1681 
1682 	queue_regulatory_request(request);
1683 
1684 	/*
1685 	 * This ensures last_request is populated once modules
1686 	 * come swinging in and calling regulatory hints and
1687 	 * wiphy_apply_custom_regulatory().
1688 	 */
1689 	flush_scheduled_work();
1690 
1691 	return 0;
1692 }
1693 
1694 /* User hints */
1695 int regulatory_hint_user(const char *alpha2)
1696 {
1697 	struct regulatory_request *request;
1698 
1699 	BUG_ON(!alpha2);
1700 
1701 	request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1702 	if (!request)
1703 		return -ENOMEM;
1704 
1705 	request->wiphy_idx = WIPHY_IDX_STALE;
1706 	request->alpha2[0] = alpha2[0];
1707 	request->alpha2[1] = alpha2[1];
1708 	request->initiator = NL80211_REGDOM_SET_BY_USER,
1709 
1710 	queue_regulatory_request(request);
1711 
1712 	return 0;
1713 }
1714 
1715 /* Driver hints */
1716 int regulatory_hint(struct wiphy *wiphy, const char *alpha2)
1717 {
1718 	struct regulatory_request *request;
1719 
1720 	BUG_ON(!alpha2);
1721 	BUG_ON(!wiphy);
1722 
1723 	request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1724 	if (!request)
1725 		return -ENOMEM;
1726 
1727 	request->wiphy_idx = get_wiphy_idx(wiphy);
1728 
1729 	/* Must have registered wiphy first */
1730 	BUG_ON(!wiphy_idx_valid(request->wiphy_idx));
1731 
1732 	request->alpha2[0] = alpha2[0];
1733 	request->alpha2[1] = alpha2[1];
1734 	request->initiator = NL80211_REGDOM_SET_BY_DRIVER;
1735 
1736 	queue_regulatory_request(request);
1737 
1738 	return 0;
1739 }
1740 EXPORT_SYMBOL(regulatory_hint);
1741 
1742 static bool reg_same_country_ie_hint(struct wiphy *wiphy,
1743 			u32 country_ie_checksum)
1744 {
1745 	struct wiphy *request_wiphy;
1746 
1747 	assert_cfg80211_lock();
1748 
1749 	if (unlikely(last_request->initiator !=
1750 	    NL80211_REGDOM_SET_BY_COUNTRY_IE))
1751 		return false;
1752 
1753 	request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
1754 
1755 	if (!request_wiphy)
1756 		return false;
1757 
1758 	if (likely(request_wiphy != wiphy))
1759 		return !country_ie_integrity_changes(country_ie_checksum);
1760 	/*
1761 	 * We should not have let these through at this point, they
1762 	 * should have been picked up earlier by the first alpha2 check
1763 	 * on the device
1764 	 */
1765 	if (WARN_ON(!country_ie_integrity_changes(country_ie_checksum)))
1766 		return true;
1767 	return false;
1768 }
1769 
1770 void regulatory_hint_11d(struct wiphy *wiphy,
1771 			u8 *country_ie,
1772 			u8 country_ie_len)
1773 {
1774 	struct ieee80211_regdomain *rd = NULL;
1775 	char alpha2[2];
1776 	u32 checksum = 0;
1777 	enum environment_cap env = ENVIRON_ANY;
1778 	struct regulatory_request *request;
1779 
1780 	mutex_lock(&cfg80211_mutex);
1781 
1782 	if (unlikely(!last_request)) {
1783 		mutex_unlock(&cfg80211_mutex);
1784 		return;
1785 	}
1786 
1787 	/* IE len must be evenly divisible by 2 */
1788 	if (country_ie_len & 0x01)
1789 		goto out;
1790 
1791 	if (country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN)
1792 		goto out;
1793 
1794 	/*
1795 	 * Pending country IE processing, this can happen after we
1796 	 * call CRDA and wait for a response if a beacon was received before
1797 	 * we were able to process the last regulatory_hint_11d() call
1798 	 */
1799 	if (country_ie_regdomain)
1800 		goto out;
1801 
1802 	alpha2[0] = country_ie[0];
1803 	alpha2[1] = country_ie[1];
1804 
1805 	if (country_ie[2] == 'I')
1806 		env = ENVIRON_INDOOR;
1807 	else if (country_ie[2] == 'O')
1808 		env = ENVIRON_OUTDOOR;
1809 
1810 	/*
1811 	 * We will run this for *every* beacon processed for the BSSID, so
1812 	 * we optimize an early check to exit out early if we don't have to
1813 	 * do anything
1814 	 */
1815 	if (likely(last_request->initiator ==
1816 	    NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1817 	    wiphy_idx_valid(last_request->wiphy_idx))) {
1818 		struct cfg80211_registered_device *drv_last_ie;
1819 
1820 		drv_last_ie =
1821 			cfg80211_drv_by_wiphy_idx(last_request->wiphy_idx);
1822 
1823 		/*
1824 		 * Lets keep this simple -- we trust the first AP
1825 		 * after we intersect with CRDA
1826 		 */
1827 		if (likely(&drv_last_ie->wiphy == wiphy)) {
1828 			/*
1829 			 * Ignore IEs coming in on this wiphy with
1830 			 * the same alpha2 and environment cap
1831 			 */
1832 			if (likely(alpha2_equal(drv_last_ie->country_ie_alpha2,
1833 				  alpha2) &&
1834 				  env == drv_last_ie->env)) {
1835 				goto out;
1836 			}
1837 			/*
1838 			 * the wiphy moved on to another BSSID or the AP
1839 			 * was reconfigured. XXX: We need to deal with the
1840 			 * case where the user suspends and goes to goes
1841 			 * to another country, and then gets IEs from an
1842 			 * AP with different settings
1843 			 */
1844 			goto out;
1845 		} else {
1846 			/*
1847 			 * Ignore IEs coming in on two separate wiphys with
1848 			 * the same alpha2 and environment cap
1849 			 */
1850 			if (likely(alpha2_equal(drv_last_ie->country_ie_alpha2,
1851 				  alpha2) &&
1852 				  env == drv_last_ie->env)) {
1853 				goto out;
1854 			}
1855 			/* We could potentially intersect though */
1856 			goto out;
1857 		}
1858 	}
1859 
1860 	rd = country_ie_2_rd(country_ie, country_ie_len, &checksum);
1861 	if (!rd)
1862 		goto out;
1863 
1864 	/*
1865 	 * This will not happen right now but we leave it here for the
1866 	 * the future when we want to add suspend/resume support and having
1867 	 * the user move to another country after doing so, or having the user
1868 	 * move to another AP. Right now we just trust the first AP.
1869 	 *
1870 	 * If we hit this before we add this support we want to be informed of
1871 	 * it as it would indicate a mistake in the current design
1872 	 */
1873 	if (WARN_ON(reg_same_country_ie_hint(wiphy, checksum)))
1874 		goto free_rd_out;
1875 
1876 	request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1877 	if (!request)
1878 		goto free_rd_out;
1879 
1880 	/*
1881 	 * We keep this around for when CRDA comes back with a response so
1882 	 * we can intersect with that
1883 	 */
1884 	country_ie_regdomain = rd;
1885 
1886 	request->wiphy_idx = get_wiphy_idx(wiphy);
1887 	request->alpha2[0] = rd->alpha2[0];
1888 	request->alpha2[1] = rd->alpha2[1];
1889 	request->initiator = NL80211_REGDOM_SET_BY_COUNTRY_IE;
1890 	request->country_ie_checksum = checksum;
1891 	request->country_ie_env = env;
1892 
1893 	mutex_unlock(&cfg80211_mutex);
1894 
1895 	queue_regulatory_request(request);
1896 
1897 	return;
1898 
1899 free_rd_out:
1900 	kfree(rd);
1901 out:
1902 	mutex_unlock(&cfg80211_mutex);
1903 }
1904 EXPORT_SYMBOL(regulatory_hint_11d);
1905 
1906 static bool freq_is_chan_12_13_14(u16 freq)
1907 {
1908 	if (freq == ieee80211_channel_to_frequency(12) ||
1909 	    freq == ieee80211_channel_to_frequency(13) ||
1910 	    freq == ieee80211_channel_to_frequency(14))
1911 		return true;
1912 	return false;
1913 }
1914 
1915 int regulatory_hint_found_beacon(struct wiphy *wiphy,
1916 				 struct ieee80211_channel *beacon_chan,
1917 				 gfp_t gfp)
1918 {
1919 	struct reg_beacon *reg_beacon;
1920 
1921 	if (likely((beacon_chan->beacon_found ||
1922 	    (beacon_chan->flags & IEEE80211_CHAN_RADAR) ||
1923 	    (beacon_chan->band == IEEE80211_BAND_2GHZ &&
1924 	     !freq_is_chan_12_13_14(beacon_chan->center_freq)))))
1925 		return 0;
1926 
1927 	reg_beacon = kzalloc(sizeof(struct reg_beacon), gfp);
1928 	if (!reg_beacon)
1929 		return -ENOMEM;
1930 
1931 #ifdef CONFIG_CFG80211_REG_DEBUG
1932 	printk(KERN_DEBUG "cfg80211: Found new beacon on "
1933 		"frequency: %d MHz (Ch %d) on %s\n",
1934 		beacon_chan->center_freq,
1935 		ieee80211_frequency_to_channel(beacon_chan->center_freq),
1936 		wiphy_name(wiphy));
1937 #endif
1938 	memcpy(&reg_beacon->chan, beacon_chan,
1939 		sizeof(struct ieee80211_channel));
1940 
1941 
1942 	/*
1943 	 * Since we can be called from BH or and non-BH context
1944 	 * we must use spin_lock_bh()
1945 	 */
1946 	spin_lock_bh(&reg_pending_beacons_lock);
1947 	list_add_tail(&reg_beacon->list, &reg_pending_beacons);
1948 	spin_unlock_bh(&reg_pending_beacons_lock);
1949 
1950 	schedule_work(&reg_work);
1951 
1952 	return 0;
1953 }
1954 
1955 static void print_rd_rules(const struct ieee80211_regdomain *rd)
1956 {
1957 	unsigned int i;
1958 	const struct ieee80211_reg_rule *reg_rule = NULL;
1959 	const struct ieee80211_freq_range *freq_range = NULL;
1960 	const struct ieee80211_power_rule *power_rule = NULL;
1961 
1962 	printk(KERN_INFO "\t(start_freq - end_freq @ bandwidth), "
1963 		"(max_antenna_gain, max_eirp)\n");
1964 
1965 	for (i = 0; i < rd->n_reg_rules; i++) {
1966 		reg_rule = &rd->reg_rules[i];
1967 		freq_range = &reg_rule->freq_range;
1968 		power_rule = &reg_rule->power_rule;
1969 
1970 		/*
1971 		 * There may not be documentation for max antenna gain
1972 		 * in certain regions
1973 		 */
1974 		if (power_rule->max_antenna_gain)
1975 			printk(KERN_INFO "\t(%d KHz - %d KHz @ %d KHz), "
1976 				"(%d mBi, %d mBm)\n",
1977 				freq_range->start_freq_khz,
1978 				freq_range->end_freq_khz,
1979 				freq_range->max_bandwidth_khz,
1980 				power_rule->max_antenna_gain,
1981 				power_rule->max_eirp);
1982 		else
1983 			printk(KERN_INFO "\t(%d KHz - %d KHz @ %d KHz), "
1984 				"(N/A, %d mBm)\n",
1985 				freq_range->start_freq_khz,
1986 				freq_range->end_freq_khz,
1987 				freq_range->max_bandwidth_khz,
1988 				power_rule->max_eirp);
1989 	}
1990 }
1991 
1992 static void print_regdomain(const struct ieee80211_regdomain *rd)
1993 {
1994 
1995 	if (is_intersected_alpha2(rd->alpha2)) {
1996 
1997 		if (last_request->initiator ==
1998 		    NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1999 			struct cfg80211_registered_device *drv;
2000 			drv = cfg80211_drv_by_wiphy_idx(
2001 				last_request->wiphy_idx);
2002 			if (drv) {
2003 				printk(KERN_INFO "cfg80211: Current regulatory "
2004 					"domain updated by AP to: %c%c\n",
2005 					drv->country_ie_alpha2[0],
2006 					drv->country_ie_alpha2[1]);
2007 			} else
2008 				printk(KERN_INFO "cfg80211: Current regulatory "
2009 					"domain intersected: \n");
2010 		} else
2011 				printk(KERN_INFO "cfg80211: Current regulatory "
2012 					"domain intersected: \n");
2013 	} else if (is_world_regdom(rd->alpha2))
2014 		printk(KERN_INFO "cfg80211: World regulatory "
2015 			"domain updated:\n");
2016 	else {
2017 		if (is_unknown_alpha2(rd->alpha2))
2018 			printk(KERN_INFO "cfg80211: Regulatory domain "
2019 				"changed to driver built-in settings "
2020 				"(unknown country)\n");
2021 		else
2022 			printk(KERN_INFO "cfg80211: Regulatory domain "
2023 				"changed to country: %c%c\n",
2024 				rd->alpha2[0], rd->alpha2[1]);
2025 	}
2026 	print_rd_rules(rd);
2027 }
2028 
2029 static void print_regdomain_info(const struct ieee80211_regdomain *rd)
2030 {
2031 	printk(KERN_INFO "cfg80211: Regulatory domain: %c%c\n",
2032 		rd->alpha2[0], rd->alpha2[1]);
2033 	print_rd_rules(rd);
2034 }
2035 
2036 #ifdef CONFIG_CFG80211_REG_DEBUG
2037 static void reg_country_ie_process_debug(
2038 	const struct ieee80211_regdomain *rd,
2039 	const struct ieee80211_regdomain *country_ie_regdomain,
2040 	const struct ieee80211_regdomain *intersected_rd)
2041 {
2042 	printk(KERN_DEBUG "cfg80211: Received country IE:\n");
2043 	print_regdomain_info(country_ie_regdomain);
2044 	printk(KERN_DEBUG "cfg80211: CRDA thinks this should applied:\n");
2045 	print_regdomain_info(rd);
2046 	if (intersected_rd) {
2047 		printk(KERN_DEBUG "cfg80211: We intersect both of these "
2048 			"and get:\n");
2049 		print_regdomain_info(intersected_rd);
2050 		return;
2051 	}
2052 	printk(KERN_DEBUG "cfg80211: Intersection between both failed\n");
2053 }
2054 #else
2055 static inline void reg_country_ie_process_debug(
2056 	const struct ieee80211_regdomain *rd,
2057 	const struct ieee80211_regdomain *country_ie_regdomain,
2058 	const struct ieee80211_regdomain *intersected_rd)
2059 {
2060 }
2061 #endif
2062 
2063 /* Takes ownership of rd only if it doesn't fail */
2064 static int __set_regdom(const struct ieee80211_regdomain *rd)
2065 {
2066 	const struct ieee80211_regdomain *intersected_rd = NULL;
2067 	struct cfg80211_registered_device *drv = NULL;
2068 	struct wiphy *request_wiphy;
2069 	/* Some basic sanity checks first */
2070 
2071 	if (is_world_regdom(rd->alpha2)) {
2072 		if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
2073 			return -EINVAL;
2074 		update_world_regdomain(rd);
2075 		return 0;
2076 	}
2077 
2078 	if (!is_alpha2_set(rd->alpha2) && !is_an_alpha2(rd->alpha2) &&
2079 			!is_unknown_alpha2(rd->alpha2))
2080 		return -EINVAL;
2081 
2082 	if (!last_request)
2083 		return -EINVAL;
2084 
2085 	/*
2086 	 * Lets only bother proceeding on the same alpha2 if the current
2087 	 * rd is non static (it means CRDA was present and was used last)
2088 	 * and the pending request came in from a country IE
2089 	 */
2090 	if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2091 		/*
2092 		 * If someone else asked us to change the rd lets only bother
2093 		 * checking if the alpha2 changes if CRDA was already called
2094 		 */
2095 		if (!is_old_static_regdom(cfg80211_regdomain) &&
2096 		    !regdom_changes(rd->alpha2))
2097 			return -EINVAL;
2098 	}
2099 
2100 	/*
2101 	 * Now lets set the regulatory domain, update all driver channels
2102 	 * and finally inform them of what we have done, in case they want
2103 	 * to review or adjust their own settings based on their own
2104 	 * internal EEPROM data
2105 	 */
2106 
2107 	if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
2108 		return -EINVAL;
2109 
2110 	if (!is_valid_rd(rd)) {
2111 		printk(KERN_ERR "cfg80211: Invalid "
2112 			"regulatory domain detected:\n");
2113 		print_regdomain_info(rd);
2114 		return -EINVAL;
2115 	}
2116 
2117 	request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
2118 
2119 	if (!last_request->intersect) {
2120 		int r;
2121 
2122 		if (last_request->initiator != NL80211_REGDOM_SET_BY_DRIVER) {
2123 			reset_regdomains();
2124 			cfg80211_regdomain = rd;
2125 			return 0;
2126 		}
2127 
2128 		/*
2129 		 * For a driver hint, lets copy the regulatory domain the
2130 		 * driver wanted to the wiphy to deal with conflicts
2131 		 */
2132 
2133 		/*
2134 		 * Userspace could have sent two replies with only
2135 		 * one kernel request.
2136 		 */
2137 		if (request_wiphy->regd)
2138 			return -EALREADY;
2139 
2140 		r = reg_copy_regd(&request_wiphy->regd, rd);
2141 		if (r)
2142 			return r;
2143 
2144 		reset_regdomains();
2145 		cfg80211_regdomain = rd;
2146 		return 0;
2147 	}
2148 
2149 	/* Intersection requires a bit more work */
2150 
2151 	if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2152 
2153 		intersected_rd = regdom_intersect(rd, cfg80211_regdomain);
2154 		if (!intersected_rd)
2155 			return -EINVAL;
2156 
2157 		/*
2158 		 * We can trash what CRDA provided now.
2159 		 * However if a driver requested this specific regulatory
2160 		 * domain we keep it for its private use
2161 		 */
2162 		if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER)
2163 			request_wiphy->regd = rd;
2164 		else
2165 			kfree(rd);
2166 
2167 		rd = NULL;
2168 
2169 		reset_regdomains();
2170 		cfg80211_regdomain = intersected_rd;
2171 
2172 		return 0;
2173 	}
2174 
2175 	/*
2176 	 * Country IE requests are handled a bit differently, we intersect
2177 	 * the country IE rd with what CRDA believes that country should have
2178 	 */
2179 
2180 	/*
2181 	 * Userspace could have sent two replies with only
2182 	 * one kernel request. By the second reply we would have
2183 	 * already processed and consumed the country_ie_regdomain.
2184 	 */
2185 	if (!country_ie_regdomain)
2186 		return -EALREADY;
2187 	BUG_ON(rd == country_ie_regdomain);
2188 
2189 	/*
2190 	 * Intersect what CRDA returned and our what we
2191 	 * had built from the Country IE received
2192 	 */
2193 
2194 	intersected_rd = regdom_intersect(rd, country_ie_regdomain);
2195 
2196 	reg_country_ie_process_debug(rd,
2197 				     country_ie_regdomain,
2198 				     intersected_rd);
2199 
2200 	kfree(country_ie_regdomain);
2201 	country_ie_regdomain = NULL;
2202 
2203 	if (!intersected_rd)
2204 		return -EINVAL;
2205 
2206 	drv = wiphy_to_dev(request_wiphy);
2207 
2208 	drv->country_ie_alpha2[0] = rd->alpha2[0];
2209 	drv->country_ie_alpha2[1] = rd->alpha2[1];
2210 	drv->env = last_request->country_ie_env;
2211 
2212 	BUG_ON(intersected_rd == rd);
2213 
2214 	kfree(rd);
2215 	rd = NULL;
2216 
2217 	reset_regdomains();
2218 	cfg80211_regdomain = intersected_rd;
2219 
2220 	return 0;
2221 }
2222 
2223 
2224 /*
2225  * Use this call to set the current regulatory domain. Conflicts with
2226  * multiple drivers can be ironed out later. Caller must've already
2227  * kmalloc'd the rd structure. Caller must hold cfg80211_mutex
2228  */
2229 int set_regdom(const struct ieee80211_regdomain *rd)
2230 {
2231 	int r;
2232 
2233 	assert_cfg80211_lock();
2234 
2235 	/* Note that this doesn't update the wiphys, this is done below */
2236 	r = __set_regdom(rd);
2237 	if (r) {
2238 		kfree(rd);
2239 		return r;
2240 	}
2241 
2242 	/* This would make this whole thing pointless */
2243 	if (!last_request->intersect)
2244 		BUG_ON(rd != cfg80211_regdomain);
2245 
2246 	/* update all wiphys now with the new established regulatory domain */
2247 	update_all_wiphy_regulatory(last_request->initiator);
2248 
2249 	print_regdomain(cfg80211_regdomain);
2250 
2251 	nl80211_send_reg_change_event(last_request);
2252 
2253 	return r;
2254 }
2255 
2256 /* Caller must hold cfg80211_mutex */
2257 void reg_device_remove(struct wiphy *wiphy)
2258 {
2259 	struct wiphy *request_wiphy = NULL;
2260 
2261 	assert_cfg80211_lock();
2262 
2263 	kfree(wiphy->regd);
2264 
2265 	if (last_request)
2266 		request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
2267 
2268 	if (!request_wiphy || request_wiphy != wiphy)
2269 		return;
2270 
2271 	last_request->wiphy_idx = WIPHY_IDX_STALE;
2272 	last_request->country_ie_env = ENVIRON_ANY;
2273 }
2274 
2275 int regulatory_init(void)
2276 {
2277 	int err = 0;
2278 
2279 	reg_pdev = platform_device_register_simple("regulatory", 0, NULL, 0);
2280 	if (IS_ERR(reg_pdev))
2281 		return PTR_ERR(reg_pdev);
2282 
2283 	spin_lock_init(&reg_requests_lock);
2284 	spin_lock_init(&reg_pending_beacons_lock);
2285 
2286 #ifdef CONFIG_WIRELESS_OLD_REGULATORY
2287 	cfg80211_regdomain = static_regdom(ieee80211_regdom);
2288 
2289 	printk(KERN_INFO "cfg80211: Using static regulatory domain info\n");
2290 	print_regdomain_info(cfg80211_regdomain);
2291 	/*
2292 	 * The old code still requests for a new regdomain and if
2293 	 * you have CRDA you get it updated, otherwise you get
2294 	 * stuck with the static values. Since "EU" is not a valid
2295 	 * ISO / IEC 3166 alpha2 code we can't expect userpace to
2296 	 * give us a regulatory domain for it. We need last_request
2297 	 * iniitalized though so lets just send a request which we
2298 	 * know will be ignored... this crap will be removed once
2299 	 * OLD_REG dies.
2300 	 */
2301 	err = regulatory_hint_core(ieee80211_regdom);
2302 #else
2303 	cfg80211_regdomain = cfg80211_world_regdom;
2304 
2305 	err = regulatory_hint_core(ieee80211_regdom);
2306 #endif
2307 	if (err) {
2308 		if (err == -ENOMEM)
2309 			return err;
2310 		/*
2311 		 * N.B. kobject_uevent_env() can fail mainly for when we're out
2312 		 * memory which is handled and propagated appropriately above
2313 		 * but it can also fail during a netlink_broadcast() or during
2314 		 * early boot for call_usermodehelper(). For now treat these
2315 		 * errors as non-fatal.
2316 		 */
2317 		printk(KERN_ERR "cfg80211: kobject_uevent_env() was unable "
2318 			"to call CRDA during init");
2319 #ifdef CONFIG_CFG80211_REG_DEBUG
2320 		/* We want to find out exactly why when debugging */
2321 		WARN_ON(err);
2322 #endif
2323 	}
2324 
2325 	return 0;
2326 }
2327 
2328 void regulatory_exit(void)
2329 {
2330 	struct regulatory_request *reg_request, *tmp;
2331 	struct reg_beacon *reg_beacon, *btmp;
2332 
2333 	cancel_work_sync(&reg_work);
2334 
2335 	mutex_lock(&cfg80211_mutex);
2336 
2337 	reset_regdomains();
2338 
2339 	kfree(country_ie_regdomain);
2340 	country_ie_regdomain = NULL;
2341 
2342 	kfree(last_request);
2343 
2344 	platform_device_unregister(reg_pdev);
2345 
2346 	spin_lock_bh(&reg_pending_beacons_lock);
2347 	if (!list_empty(&reg_pending_beacons)) {
2348 		list_for_each_entry_safe(reg_beacon, btmp,
2349 					 &reg_pending_beacons, list) {
2350 			list_del(&reg_beacon->list);
2351 			kfree(reg_beacon);
2352 		}
2353 	}
2354 	spin_unlock_bh(&reg_pending_beacons_lock);
2355 
2356 	if (!list_empty(&reg_beacon_list)) {
2357 		list_for_each_entry_safe(reg_beacon, btmp,
2358 					 &reg_beacon_list, list) {
2359 			list_del(&reg_beacon->list);
2360 			kfree(reg_beacon);
2361 		}
2362 	}
2363 
2364 	spin_lock(&reg_requests_lock);
2365 	if (!list_empty(&reg_requests_list)) {
2366 		list_for_each_entry_safe(reg_request, tmp,
2367 					 &reg_requests_list, list) {
2368 			list_del(&reg_request->list);
2369 			kfree(reg_request);
2370 		}
2371 	}
2372 	spin_unlock(&reg_requests_lock);
2373 
2374 	mutex_unlock(&cfg80211_mutex);
2375 }
2376