xref: /openbmc/linux/net/wireless/reg.c (revision b04b4f78)
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/wireless.h>
41 #include <net/cfg80211.h>
42 #include "core.h"
43 #include "reg.h"
44 #include "nl80211.h"
45 
46 /* Receipt of information from last regulatory request */
47 static struct regulatory_request *last_request;
48 
49 /* To trigger userspace events */
50 static struct platform_device *reg_pdev;
51 
52 /* Keep the ordering from large to small */
53 static u32 supported_bandwidths[] = {
54 	MHZ_TO_KHZ(40),
55 	MHZ_TO_KHZ(20),
56 };
57 
58 /*
59  * Central wireless core regulatory domains, we only need two,
60  * the current one and a world regulatory domain in case we have no
61  * information to give us an alpha2
62  */
63 const struct ieee80211_regdomain *cfg80211_regdomain;
64 
65 /*
66  * We use this as a place for the rd structure built from the
67  * last parsed country IE to rest until CRDA gets back to us with
68  * what it thinks should apply for the same country
69  */
70 static const struct ieee80211_regdomain *country_ie_regdomain;
71 
72 /* Used to queue up regulatory hints */
73 static LIST_HEAD(reg_requests_list);
74 static spinlock_t reg_requests_lock;
75 
76 /* Used to queue up beacon hints for review */
77 static LIST_HEAD(reg_pending_beacons);
78 static spinlock_t reg_pending_beacons_lock;
79 
80 /* Used to keep track of processed beacon hints */
81 static LIST_HEAD(reg_beacon_list);
82 
83 struct reg_beacon {
84 	struct list_head list;
85 	struct ieee80211_channel chan;
86 };
87 
88 /* We keep a static world regulatory domain in case of the absence of CRDA */
89 static const struct ieee80211_regdomain world_regdom = {
90 	.n_reg_rules = 5,
91 	.alpha2 =  "00",
92 	.reg_rules = {
93 		/* IEEE 802.11b/g, channels 1..11 */
94 		REG_RULE(2412-10, 2462+10, 40, 6, 20, 0),
95 		/* IEEE 802.11b/g, channels 12..13. No HT40
96 		 * channel fits here. */
97 		REG_RULE(2467-10, 2472+10, 20, 6, 20,
98 			NL80211_RRF_PASSIVE_SCAN |
99 			NL80211_RRF_NO_IBSS),
100 		/* IEEE 802.11 channel 14 - Only JP enables
101 		 * this and for 802.11b only */
102 		REG_RULE(2484-10, 2484+10, 20, 6, 20,
103 			NL80211_RRF_PASSIVE_SCAN |
104 			NL80211_RRF_NO_IBSS |
105 			NL80211_RRF_NO_OFDM),
106 		/* IEEE 802.11a, channel 36..48 */
107 		REG_RULE(5180-10, 5240+10, 40, 6, 20,
108                         NL80211_RRF_PASSIVE_SCAN |
109                         NL80211_RRF_NO_IBSS),
110 
111 		/* NB: 5260 MHz - 5700 MHz requies DFS */
112 
113 		/* IEEE 802.11a, channel 149..165 */
114 		REG_RULE(5745-10, 5825+10, 40, 6, 20,
115 			NL80211_RRF_PASSIVE_SCAN |
116 			NL80211_RRF_NO_IBSS),
117 	}
118 };
119 
120 static const struct ieee80211_regdomain *cfg80211_world_regdom =
121 	&world_regdom;
122 
123 #ifdef CONFIG_WIRELESS_OLD_REGULATORY
124 static char *ieee80211_regdom = "US";
125 #else
126 static char *ieee80211_regdom = "00";
127 #endif
128 
129 module_param(ieee80211_regdom, charp, 0444);
130 MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain code");
131 
132 #ifdef CONFIG_WIRELESS_OLD_REGULATORY
133 /*
134  * We assume 40 MHz bandwidth for the old regulatory work.
135  * We make emphasis we are using the exact same frequencies
136  * as before
137  */
138 
139 static const struct ieee80211_regdomain us_regdom = {
140 	.n_reg_rules = 6,
141 	.alpha2 =  "US",
142 	.reg_rules = {
143 		/* IEEE 802.11b/g, channels 1..11 */
144 		REG_RULE(2412-10, 2462+10, 40, 6, 27, 0),
145 		/* IEEE 802.11a, channel 36 */
146 		REG_RULE(5180-10, 5180+10, 40, 6, 23, 0),
147 		/* IEEE 802.11a, channel 40 */
148 		REG_RULE(5200-10, 5200+10, 40, 6, 23, 0),
149 		/* IEEE 802.11a, channel 44 */
150 		REG_RULE(5220-10, 5220+10, 40, 6, 23, 0),
151 		/* IEEE 802.11a, channels 48..64 */
152 		REG_RULE(5240-10, 5320+10, 40, 6, 23, 0),
153 		/* IEEE 802.11a, channels 149..165, outdoor */
154 		REG_RULE(5745-10, 5825+10, 40, 6, 30, 0),
155 	}
156 };
157 
158 static const struct ieee80211_regdomain jp_regdom = {
159 	.n_reg_rules = 3,
160 	.alpha2 =  "JP",
161 	.reg_rules = {
162 		/* IEEE 802.11b/g, channels 1..14 */
163 		REG_RULE(2412-10, 2484+10, 40, 6, 20, 0),
164 		/* IEEE 802.11a, channels 34..48 */
165 		REG_RULE(5170-10, 5240+10, 40, 6, 20,
166 			NL80211_RRF_PASSIVE_SCAN),
167 		/* IEEE 802.11a, channels 52..64 */
168 		REG_RULE(5260-10, 5320+10, 40, 6, 20,
169 			NL80211_RRF_NO_IBSS |
170 			NL80211_RRF_DFS),
171 	}
172 };
173 
174 static const struct ieee80211_regdomain eu_regdom = {
175 	.n_reg_rules = 6,
176 	/*
177 	 * This alpha2 is bogus, we leave it here just for stupid
178 	 * backward compatibility
179 	 */
180 	.alpha2 =  "EU",
181 	.reg_rules = {
182 		/* IEEE 802.11b/g, channels 1..13 */
183 		REG_RULE(2412-10, 2472+10, 40, 6, 20, 0),
184 		/* IEEE 802.11a, channel 36 */
185 		REG_RULE(5180-10, 5180+10, 40, 6, 23,
186 			NL80211_RRF_PASSIVE_SCAN),
187 		/* IEEE 802.11a, channel 40 */
188 		REG_RULE(5200-10, 5200+10, 40, 6, 23,
189 			NL80211_RRF_PASSIVE_SCAN),
190 		/* IEEE 802.11a, channel 44 */
191 		REG_RULE(5220-10, 5220+10, 40, 6, 23,
192 			NL80211_RRF_PASSIVE_SCAN),
193 		/* IEEE 802.11a, channels 48..64 */
194 		REG_RULE(5240-10, 5320+10, 40, 6, 20,
195 			NL80211_RRF_NO_IBSS |
196 			NL80211_RRF_DFS),
197 		/* IEEE 802.11a, channels 100..140 */
198 		REG_RULE(5500-10, 5700+10, 40, 6, 30,
199 			NL80211_RRF_NO_IBSS |
200 			NL80211_RRF_DFS),
201 	}
202 };
203 
204 static const struct ieee80211_regdomain *static_regdom(char *alpha2)
205 {
206 	if (alpha2[0] == 'U' && alpha2[1] == 'S')
207 		return &us_regdom;
208 	if (alpha2[0] == 'J' && alpha2[1] == 'P')
209 		return &jp_regdom;
210 	if (alpha2[0] == 'E' && alpha2[1] == 'U')
211 		return &eu_regdom;
212 	/* Default, as per the old rules */
213 	return &us_regdom;
214 }
215 
216 static bool is_old_static_regdom(const struct ieee80211_regdomain *rd)
217 {
218 	if (rd == &us_regdom || rd == &jp_regdom || rd == &eu_regdom)
219 		return true;
220 	return false;
221 }
222 #else
223 static inline bool is_old_static_regdom(const struct ieee80211_regdomain *rd)
224 {
225 	return false;
226 }
227 #endif
228 
229 static void reset_regdomains(void)
230 {
231 	/* avoid freeing static information or freeing something twice */
232 	if (cfg80211_regdomain == cfg80211_world_regdom)
233 		cfg80211_regdomain = NULL;
234 	if (cfg80211_world_regdom == &world_regdom)
235 		cfg80211_world_regdom = NULL;
236 	if (cfg80211_regdomain == &world_regdom)
237 		cfg80211_regdomain = NULL;
238 	if (is_old_static_regdom(cfg80211_regdomain))
239 		cfg80211_regdomain = NULL;
240 
241 	kfree(cfg80211_regdomain);
242 	kfree(cfg80211_world_regdom);
243 
244 	cfg80211_world_regdom = &world_regdom;
245 	cfg80211_regdomain = NULL;
246 }
247 
248 /*
249  * Dynamic world regulatory domain requested by the wireless
250  * core upon initialization
251  */
252 static void update_world_regdomain(const struct ieee80211_regdomain *rd)
253 {
254 	BUG_ON(!last_request);
255 
256 	reset_regdomains();
257 
258 	cfg80211_world_regdom = rd;
259 	cfg80211_regdomain = rd;
260 }
261 
262 bool is_world_regdom(const char *alpha2)
263 {
264 	if (!alpha2)
265 		return false;
266 	if (alpha2[0] == '0' && alpha2[1] == '0')
267 		return true;
268 	return false;
269 }
270 
271 static bool is_alpha2_set(const char *alpha2)
272 {
273 	if (!alpha2)
274 		return false;
275 	if (alpha2[0] != 0 && alpha2[1] != 0)
276 		return true;
277 	return false;
278 }
279 
280 static bool is_alpha_upper(char letter)
281 {
282 	/* ASCII A - Z */
283 	if (letter >= 65 && letter <= 90)
284 		return true;
285 	return false;
286 }
287 
288 static bool is_unknown_alpha2(const char *alpha2)
289 {
290 	if (!alpha2)
291 		return false;
292 	/*
293 	 * Special case where regulatory domain was built by driver
294 	 * but a specific alpha2 cannot be determined
295 	 */
296 	if (alpha2[0] == '9' && alpha2[1] == '9')
297 		return true;
298 	return false;
299 }
300 
301 static bool is_intersected_alpha2(const char *alpha2)
302 {
303 	if (!alpha2)
304 		return false;
305 	/*
306 	 * Special case where regulatory domain is the
307 	 * result of an intersection between two regulatory domain
308 	 * structures
309 	 */
310 	if (alpha2[0] == '9' && alpha2[1] == '8')
311 		return true;
312 	return false;
313 }
314 
315 static bool is_an_alpha2(const char *alpha2)
316 {
317 	if (!alpha2)
318 		return false;
319 	if (is_alpha_upper(alpha2[0]) && is_alpha_upper(alpha2[1]))
320 		return true;
321 	return false;
322 }
323 
324 static bool alpha2_equal(const char *alpha2_x, const char *alpha2_y)
325 {
326 	if (!alpha2_x || !alpha2_y)
327 		return false;
328 	if (alpha2_x[0] == alpha2_y[0] &&
329 		alpha2_x[1] == alpha2_y[1])
330 		return true;
331 	return false;
332 }
333 
334 static bool regdom_changes(const char *alpha2)
335 {
336 	assert_cfg80211_lock();
337 
338 	if (!cfg80211_regdomain)
339 		return true;
340 	if (alpha2_equal(cfg80211_regdomain->alpha2, alpha2))
341 		return false;
342 	return true;
343 }
344 
345 /**
346  * country_ie_integrity_changes - tells us if the country IE has changed
347  * @checksum: checksum of country IE of fields we are interested in
348  *
349  * If the country IE has not changed you can ignore it safely. This is
350  * useful to determine if two devices are seeing two different country IEs
351  * even on the same alpha2. Note that this will return false if no IE has
352  * been set on the wireless core yet.
353  */
354 static bool country_ie_integrity_changes(u32 checksum)
355 {
356 	/* If no IE has been set then the checksum doesn't change */
357 	if (unlikely(!last_request->country_ie_checksum))
358 		return false;
359 	if (unlikely(last_request->country_ie_checksum != checksum))
360 		return true;
361 	return false;
362 }
363 
364 /*
365  * This lets us keep regulatory code which is updated on a regulatory
366  * basis in userspace.
367  */
368 static int call_crda(const char *alpha2)
369 {
370 	char country_env[9 + 2] = "COUNTRY=";
371 	char *envp[] = {
372 		country_env,
373 		NULL
374 	};
375 
376 	if (!is_world_regdom((char *) alpha2))
377 		printk(KERN_INFO "cfg80211: Calling CRDA for country: %c%c\n",
378 			alpha2[0], alpha2[1]);
379 	else
380 		printk(KERN_INFO "cfg80211: Calling CRDA to update world "
381 			"regulatory domain\n");
382 
383 	country_env[8] = alpha2[0];
384 	country_env[9] = alpha2[1];
385 
386 	return kobject_uevent_env(&reg_pdev->dev.kobj, KOBJ_CHANGE, envp);
387 }
388 
389 /* Used by nl80211 before kmalloc'ing our regulatory domain */
390 bool reg_is_valid_request(const char *alpha2)
391 {
392 	if (!last_request)
393 		return false;
394 
395 	return alpha2_equal(last_request->alpha2, alpha2);
396 }
397 
398 /* Sanity check on a regulatory rule */
399 static bool is_valid_reg_rule(const struct ieee80211_reg_rule *rule)
400 {
401 	const struct ieee80211_freq_range *freq_range = &rule->freq_range;
402 	u32 freq_diff;
403 
404 	if (freq_range->start_freq_khz <= 0 || freq_range->end_freq_khz <= 0)
405 		return false;
406 
407 	if (freq_range->start_freq_khz > freq_range->end_freq_khz)
408 		return false;
409 
410 	freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
411 
412 	if (freq_range->end_freq_khz <= freq_range->start_freq_khz ||
413 			freq_range->max_bandwidth_khz > freq_diff)
414 		return false;
415 
416 	return true;
417 }
418 
419 static bool is_valid_rd(const struct ieee80211_regdomain *rd)
420 {
421 	const struct ieee80211_reg_rule *reg_rule = NULL;
422 	unsigned int i;
423 
424 	if (!rd->n_reg_rules)
425 		return false;
426 
427 	if (WARN_ON(rd->n_reg_rules > NL80211_MAX_SUPP_REG_RULES))
428 		return false;
429 
430 	for (i = 0; i < rd->n_reg_rules; i++) {
431 		reg_rule = &rd->reg_rules[i];
432 		if (!is_valid_reg_rule(reg_rule))
433 			return false;
434 	}
435 
436 	return true;
437 }
438 
439 /* Returns value in KHz */
440 static u32 freq_max_bandwidth(const struct ieee80211_freq_range *freq_range,
441 	u32 freq)
442 {
443 	unsigned int i;
444 	for (i = 0; i < ARRAY_SIZE(supported_bandwidths); i++) {
445 		u32 start_freq_khz = freq - supported_bandwidths[i]/2;
446 		u32 end_freq_khz = freq + supported_bandwidths[i]/2;
447 		if (start_freq_khz >= freq_range->start_freq_khz &&
448 			end_freq_khz <= freq_range->end_freq_khz)
449 			return supported_bandwidths[i];
450 	}
451 	return 0;
452 }
453 
454 /**
455  * freq_in_rule_band - tells us if a frequency is in a frequency band
456  * @freq_range: frequency rule we want to query
457  * @freq_khz: frequency we are inquiring about
458  *
459  * This lets us know if a specific frequency rule is or is not relevant to
460  * a specific frequency's band. Bands are device specific and artificial
461  * definitions (the "2.4 GHz band" and the "5 GHz band"), however it is
462  * safe for now to assume that a frequency rule should not be part of a
463  * frequency's band if the start freq or end freq are off by more than 2 GHz.
464  * This resolution can be lowered and should be considered as we add
465  * regulatory rule support for other "bands".
466  **/
467 static bool freq_in_rule_band(const struct ieee80211_freq_range *freq_range,
468 	u32 freq_khz)
469 {
470 #define ONE_GHZ_IN_KHZ	1000000
471 	if (abs(freq_khz - freq_range->start_freq_khz) <= (2 * ONE_GHZ_IN_KHZ))
472 		return true;
473 	if (abs(freq_khz - freq_range->end_freq_khz) <= (2 * ONE_GHZ_IN_KHZ))
474 		return true;
475 	return false;
476 #undef ONE_GHZ_IN_KHZ
477 }
478 
479 /*
480  * Converts a country IE to a regulatory domain. A regulatory domain
481  * structure has a lot of information which the IE doesn't yet have,
482  * so for the other values we use upper max values as we will intersect
483  * with our userspace regulatory agent to get lower bounds.
484  */
485 static struct ieee80211_regdomain *country_ie_2_rd(
486 				u8 *country_ie,
487 				u8 country_ie_len,
488 				u32 *checksum)
489 {
490 	struct ieee80211_regdomain *rd = NULL;
491 	unsigned int i = 0;
492 	char alpha2[2];
493 	u32 flags = 0;
494 	u32 num_rules = 0, size_of_regd = 0;
495 	u8 *triplets_start = NULL;
496 	u8 len_at_triplet = 0;
497 	/* the last channel we have registered in a subband (triplet) */
498 	int last_sub_max_channel = 0;
499 
500 	*checksum = 0xDEADBEEF;
501 
502 	/* Country IE requirements */
503 	BUG_ON(country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN ||
504 		country_ie_len & 0x01);
505 
506 	alpha2[0] = country_ie[0];
507 	alpha2[1] = country_ie[1];
508 
509 	/*
510 	 * Third octet can be:
511 	 *    'I' - Indoor
512 	 *    'O' - Outdoor
513 	 *
514 	 *  anything else we assume is no restrictions
515 	 */
516 	if (country_ie[2] == 'I')
517 		flags = NL80211_RRF_NO_OUTDOOR;
518 	else if (country_ie[2] == 'O')
519 		flags = NL80211_RRF_NO_INDOOR;
520 
521 	country_ie += 3;
522 	country_ie_len -= 3;
523 
524 	triplets_start = country_ie;
525 	len_at_triplet = country_ie_len;
526 
527 	*checksum ^= ((flags ^ alpha2[0] ^ alpha2[1]) << 8);
528 
529 	/*
530 	 * We need to build a reg rule for each triplet, but first we must
531 	 * calculate the number of reg rules we will need. We will need one
532 	 * for each channel subband
533 	 */
534 	while (country_ie_len >= 3) {
535 		int end_channel = 0;
536 		struct ieee80211_country_ie_triplet *triplet =
537 			(struct ieee80211_country_ie_triplet *) country_ie;
538 		int cur_sub_max_channel = 0, cur_channel = 0;
539 
540 		if (triplet->ext.reg_extension_id >=
541 				IEEE80211_COUNTRY_EXTENSION_ID) {
542 			country_ie += 3;
543 			country_ie_len -= 3;
544 			continue;
545 		}
546 
547 		/* 2 GHz */
548 		if (triplet->chans.first_channel <= 14)
549 			end_channel = triplet->chans.first_channel +
550 				triplet->chans.num_channels;
551 		else
552 			/*
553 			 * 5 GHz -- For example in country IEs if the first
554 			 * channel given is 36 and the number of channels is 4
555 			 * then the individual channel numbers defined for the
556 			 * 5 GHz PHY by these parameters are: 36, 40, 44, and 48
557 			 * and not 36, 37, 38, 39.
558 			 *
559 			 * See: http://tinyurl.com/11d-clarification
560 			 */
561 			end_channel =  triplet->chans.first_channel +
562 				(4 * (triplet->chans.num_channels - 1));
563 
564 		cur_channel = triplet->chans.first_channel;
565 		cur_sub_max_channel = end_channel;
566 
567 		/* Basic sanity check */
568 		if (cur_sub_max_channel < cur_channel)
569 			return NULL;
570 
571 		/*
572 		 * Do not allow overlapping channels. Also channels
573 		 * passed in each subband must be monotonically
574 		 * increasing
575 		 */
576 		if (last_sub_max_channel) {
577 			if (cur_channel <= last_sub_max_channel)
578 				return NULL;
579 			if (cur_sub_max_channel <= last_sub_max_channel)
580 				return NULL;
581 		}
582 
583 		/*
584 		 * When dot11RegulatoryClassesRequired is supported
585 		 * we can throw ext triplets as part of this soup,
586 		 * for now we don't care when those change as we
587 		 * don't support them
588 		 */
589 		*checksum ^= ((cur_channel ^ cur_sub_max_channel) << 8) |
590 		  ((cur_sub_max_channel ^ cur_sub_max_channel) << 16) |
591 		  ((triplet->chans.max_power ^ cur_sub_max_channel) << 24);
592 
593 		last_sub_max_channel = cur_sub_max_channel;
594 
595 		country_ie += 3;
596 		country_ie_len -= 3;
597 		num_rules++;
598 
599 		/*
600 		 * Note: this is not a IEEE requirement but
601 		 * simply a memory requirement
602 		 */
603 		if (num_rules > NL80211_MAX_SUPP_REG_RULES)
604 			return NULL;
605 	}
606 
607 	country_ie = triplets_start;
608 	country_ie_len = len_at_triplet;
609 
610 	size_of_regd = sizeof(struct ieee80211_regdomain) +
611 		(num_rules * sizeof(struct ieee80211_reg_rule));
612 
613 	rd = kzalloc(size_of_regd, GFP_KERNEL);
614 	if (!rd)
615 		return NULL;
616 
617 	rd->n_reg_rules = num_rules;
618 	rd->alpha2[0] = alpha2[0];
619 	rd->alpha2[1] = alpha2[1];
620 
621 	/* This time around we fill in the rd */
622 	while (country_ie_len >= 3) {
623 		int end_channel = 0;
624 		struct ieee80211_country_ie_triplet *triplet =
625 			(struct ieee80211_country_ie_triplet *) country_ie;
626 		struct ieee80211_reg_rule *reg_rule = NULL;
627 		struct ieee80211_freq_range *freq_range = NULL;
628 		struct ieee80211_power_rule *power_rule = NULL;
629 
630 		/*
631 		 * Must parse if dot11RegulatoryClassesRequired is true,
632 		 * we don't support this yet
633 		 */
634 		if (triplet->ext.reg_extension_id >=
635 				IEEE80211_COUNTRY_EXTENSION_ID) {
636 			country_ie += 3;
637 			country_ie_len -= 3;
638 			continue;
639 		}
640 
641 		reg_rule = &rd->reg_rules[i];
642 		freq_range = &reg_rule->freq_range;
643 		power_rule = &reg_rule->power_rule;
644 
645 		reg_rule->flags = flags;
646 
647 		/* 2 GHz */
648 		if (triplet->chans.first_channel <= 14)
649 			end_channel = triplet->chans.first_channel +
650 				triplet->chans.num_channels;
651 		else
652 			end_channel =  triplet->chans.first_channel +
653 				(4 * (triplet->chans.num_channels - 1));
654 
655 		/*
656 		 * The +10 is since the regulatory domain expects
657 		 * the actual band edge, not the center of freq for
658 		 * its start and end freqs, assuming 20 MHz bandwidth on
659 		 * the channels passed
660 		 */
661 		freq_range->start_freq_khz =
662 			MHZ_TO_KHZ(ieee80211_channel_to_frequency(
663 				triplet->chans.first_channel) - 10);
664 		freq_range->end_freq_khz =
665 			MHZ_TO_KHZ(ieee80211_channel_to_frequency(
666 				end_channel) + 10);
667 
668 		/*
669 		 * These are large arbitrary values we use to intersect later.
670 		 * Increment this if we ever support >= 40 MHz channels
671 		 * in IEEE 802.11
672 		 */
673 		freq_range->max_bandwidth_khz = MHZ_TO_KHZ(40);
674 		power_rule->max_antenna_gain = DBI_TO_MBI(100);
675 		power_rule->max_eirp = DBM_TO_MBM(100);
676 
677 		country_ie += 3;
678 		country_ie_len -= 3;
679 		i++;
680 
681 		BUG_ON(i > NL80211_MAX_SUPP_REG_RULES);
682 	}
683 
684 	return rd;
685 }
686 
687 
688 /*
689  * Helper for regdom_intersect(), this does the real
690  * mathematical intersection fun
691  */
692 static int reg_rules_intersect(
693 	const struct ieee80211_reg_rule *rule1,
694 	const struct ieee80211_reg_rule *rule2,
695 	struct ieee80211_reg_rule *intersected_rule)
696 {
697 	const struct ieee80211_freq_range *freq_range1, *freq_range2;
698 	struct ieee80211_freq_range *freq_range;
699 	const struct ieee80211_power_rule *power_rule1, *power_rule2;
700 	struct ieee80211_power_rule *power_rule;
701 	u32 freq_diff;
702 
703 	freq_range1 = &rule1->freq_range;
704 	freq_range2 = &rule2->freq_range;
705 	freq_range = &intersected_rule->freq_range;
706 
707 	power_rule1 = &rule1->power_rule;
708 	power_rule2 = &rule2->power_rule;
709 	power_rule = &intersected_rule->power_rule;
710 
711 	freq_range->start_freq_khz = max(freq_range1->start_freq_khz,
712 		freq_range2->start_freq_khz);
713 	freq_range->end_freq_khz = min(freq_range1->end_freq_khz,
714 		freq_range2->end_freq_khz);
715 	freq_range->max_bandwidth_khz = min(freq_range1->max_bandwidth_khz,
716 		freq_range2->max_bandwidth_khz);
717 
718 	freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
719 	if (freq_range->max_bandwidth_khz > freq_diff)
720 		freq_range->max_bandwidth_khz = freq_diff;
721 
722 	power_rule->max_eirp = min(power_rule1->max_eirp,
723 		power_rule2->max_eirp);
724 	power_rule->max_antenna_gain = min(power_rule1->max_antenna_gain,
725 		power_rule2->max_antenna_gain);
726 
727 	intersected_rule->flags = (rule1->flags | rule2->flags);
728 
729 	if (!is_valid_reg_rule(intersected_rule))
730 		return -EINVAL;
731 
732 	return 0;
733 }
734 
735 /**
736  * regdom_intersect - do the intersection between two regulatory domains
737  * @rd1: first regulatory domain
738  * @rd2: second regulatory domain
739  *
740  * Use this function to get the intersection between two regulatory domains.
741  * Once completed we will mark the alpha2 for the rd as intersected, "98",
742  * as no one single alpha2 can represent this regulatory domain.
743  *
744  * Returns a pointer to the regulatory domain structure which will hold the
745  * resulting intersection of rules between rd1 and rd2. We will
746  * kzalloc() this structure for you.
747  */
748 static struct ieee80211_regdomain *regdom_intersect(
749 	const struct ieee80211_regdomain *rd1,
750 	const struct ieee80211_regdomain *rd2)
751 {
752 	int r, size_of_regd;
753 	unsigned int x, y;
754 	unsigned int num_rules = 0, rule_idx = 0;
755 	const struct ieee80211_reg_rule *rule1, *rule2;
756 	struct ieee80211_reg_rule *intersected_rule;
757 	struct ieee80211_regdomain *rd;
758 	/* This is just a dummy holder to help us count */
759 	struct ieee80211_reg_rule irule;
760 
761 	/* Uses the stack temporarily for counter arithmetic */
762 	intersected_rule = &irule;
763 
764 	memset(intersected_rule, 0, sizeof(struct ieee80211_reg_rule));
765 
766 	if (!rd1 || !rd2)
767 		return NULL;
768 
769 	/*
770 	 * First we get a count of the rules we'll need, then we actually
771 	 * build them. This is to so we can malloc() and free() a
772 	 * regdomain once. The reason we use reg_rules_intersect() here
773 	 * is it will return -EINVAL if the rule computed makes no sense.
774 	 * All rules that do check out OK are valid.
775 	 */
776 
777 	for (x = 0; x < rd1->n_reg_rules; x++) {
778 		rule1 = &rd1->reg_rules[x];
779 		for (y = 0; y < rd2->n_reg_rules; y++) {
780 			rule2 = &rd2->reg_rules[y];
781 			if (!reg_rules_intersect(rule1, rule2,
782 					intersected_rule))
783 				num_rules++;
784 			memset(intersected_rule, 0,
785 					sizeof(struct ieee80211_reg_rule));
786 		}
787 	}
788 
789 	if (!num_rules)
790 		return NULL;
791 
792 	size_of_regd = sizeof(struct ieee80211_regdomain) +
793 		((num_rules + 1) * sizeof(struct ieee80211_reg_rule));
794 
795 	rd = kzalloc(size_of_regd, GFP_KERNEL);
796 	if (!rd)
797 		return NULL;
798 
799 	for (x = 0; x < rd1->n_reg_rules; x++) {
800 		rule1 = &rd1->reg_rules[x];
801 		for (y = 0; y < rd2->n_reg_rules; y++) {
802 			rule2 = &rd2->reg_rules[y];
803 			/*
804 			 * This time around instead of using the stack lets
805 			 * write to the target rule directly saving ourselves
806 			 * a memcpy()
807 			 */
808 			intersected_rule = &rd->reg_rules[rule_idx];
809 			r = reg_rules_intersect(rule1, rule2,
810 				intersected_rule);
811 			/*
812 			 * No need to memset here the intersected rule here as
813 			 * we're not using the stack anymore
814 			 */
815 			if (r)
816 				continue;
817 			rule_idx++;
818 		}
819 	}
820 
821 	if (rule_idx != num_rules) {
822 		kfree(rd);
823 		return NULL;
824 	}
825 
826 	rd->n_reg_rules = num_rules;
827 	rd->alpha2[0] = '9';
828 	rd->alpha2[1] = '8';
829 
830 	return rd;
831 }
832 
833 /*
834  * XXX: add support for the rest of enum nl80211_reg_rule_flags, we may
835  * want to just have the channel structure use these
836  */
837 static u32 map_regdom_flags(u32 rd_flags)
838 {
839 	u32 channel_flags = 0;
840 	if (rd_flags & NL80211_RRF_PASSIVE_SCAN)
841 		channel_flags |= IEEE80211_CHAN_PASSIVE_SCAN;
842 	if (rd_flags & NL80211_RRF_NO_IBSS)
843 		channel_flags |= IEEE80211_CHAN_NO_IBSS;
844 	if (rd_flags & NL80211_RRF_DFS)
845 		channel_flags |= IEEE80211_CHAN_RADAR;
846 	return channel_flags;
847 }
848 
849 static int freq_reg_info_regd(struct wiphy *wiphy,
850 			      u32 center_freq,
851 			      u32 *bandwidth,
852 			      const struct ieee80211_reg_rule **reg_rule,
853 			      const struct ieee80211_regdomain *custom_regd)
854 {
855 	int i;
856 	bool band_rule_found = false;
857 	const struct ieee80211_regdomain *regd;
858 	u32 max_bandwidth = 0;
859 
860 	regd = custom_regd ? custom_regd : cfg80211_regdomain;
861 
862 	/*
863 	 * Follow the driver's regulatory domain, if present, unless a country
864 	 * IE has been processed or a user wants to help complaince further
865 	 */
866 	if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
867 	    last_request->initiator != NL80211_REGDOM_SET_BY_USER &&
868 	    wiphy->regd)
869 		regd = wiphy->regd;
870 
871 	if (!regd)
872 		return -EINVAL;
873 
874 	for (i = 0; i < regd->n_reg_rules; i++) {
875 		const struct ieee80211_reg_rule *rr;
876 		const struct ieee80211_freq_range *fr = NULL;
877 		const struct ieee80211_power_rule *pr = NULL;
878 
879 		rr = &regd->reg_rules[i];
880 		fr = &rr->freq_range;
881 		pr = &rr->power_rule;
882 
883 		/*
884 		 * We only need to know if one frequency rule was
885 		 * was in center_freq's band, that's enough, so lets
886 		 * not overwrite it once found
887 		 */
888 		if (!band_rule_found)
889 			band_rule_found = freq_in_rule_band(fr, center_freq);
890 
891 		max_bandwidth = freq_max_bandwidth(fr, center_freq);
892 
893 		if (max_bandwidth && *bandwidth <= max_bandwidth) {
894 			*reg_rule = rr;
895 			*bandwidth = max_bandwidth;
896 			break;
897 		}
898 	}
899 
900 	if (!band_rule_found)
901 		return -ERANGE;
902 
903 	return !max_bandwidth;
904 }
905 EXPORT_SYMBOL(freq_reg_info);
906 
907 int freq_reg_info(struct wiphy *wiphy, u32 center_freq, u32 *bandwidth,
908 			 const struct ieee80211_reg_rule **reg_rule)
909 {
910 	assert_cfg80211_lock();
911 	return freq_reg_info_regd(wiphy, center_freq,
912 		bandwidth, reg_rule, NULL);
913 }
914 
915 static void handle_channel(struct wiphy *wiphy, enum ieee80211_band band,
916 			   unsigned int chan_idx)
917 {
918 	int r;
919 	u32 flags;
920 	u32 max_bandwidth = 0;
921 	const struct ieee80211_reg_rule *reg_rule = NULL;
922 	const struct ieee80211_power_rule *power_rule = NULL;
923 	struct ieee80211_supported_band *sband;
924 	struct ieee80211_channel *chan;
925 	struct wiphy *request_wiphy = NULL;
926 
927 	assert_cfg80211_lock();
928 
929 	request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
930 
931 	sband = wiphy->bands[band];
932 	BUG_ON(chan_idx >= sband->n_channels);
933 	chan = &sband->channels[chan_idx];
934 
935 	flags = chan->orig_flags;
936 
937 	r = freq_reg_info(wiphy, MHZ_TO_KHZ(chan->center_freq),
938 		&max_bandwidth, &reg_rule);
939 
940 	if (r) {
941 		/*
942 		 * This means no regulatory rule was found in the country IE
943 		 * with a frequency range on the center_freq's band, since
944 		 * IEEE-802.11 allows for a country IE to have a subset of the
945 		 * regulatory information provided in a country we ignore
946 		 * disabling the channel unless at least one reg rule was
947 		 * found on the center_freq's band. For details see this
948 		 * clarification:
949 		 *
950 		 * http://tinyurl.com/11d-clarification
951 		 */
952 		if (r == -ERANGE &&
953 		    last_request->initiator ==
954 		    NL80211_REGDOM_SET_BY_COUNTRY_IE) {
955 #ifdef CONFIG_CFG80211_REG_DEBUG
956 			printk(KERN_DEBUG "cfg80211: Leaving channel %d MHz "
957 				"intact on %s - no rule found in band on "
958 				"Country IE\n",
959 				chan->center_freq, wiphy_name(wiphy));
960 #endif
961 		} else {
962 		/*
963 		 * In this case we know the country IE has at least one reg rule
964 		 * for the band so we respect its band definitions
965 		 */
966 #ifdef CONFIG_CFG80211_REG_DEBUG
967 			if (last_request->initiator ==
968 			    NL80211_REGDOM_SET_BY_COUNTRY_IE)
969 				printk(KERN_DEBUG "cfg80211: Disabling "
970 					"channel %d MHz on %s due to "
971 					"Country IE\n",
972 					chan->center_freq, wiphy_name(wiphy));
973 #endif
974 			flags |= IEEE80211_CHAN_DISABLED;
975 			chan->flags = flags;
976 		}
977 		return;
978 	}
979 
980 	power_rule = &reg_rule->power_rule;
981 
982 	if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
983 	    request_wiphy && request_wiphy == wiphy &&
984 	    request_wiphy->strict_regulatory) {
985 		/*
986 		 * This gaurantees the driver's requested regulatory domain
987 		 * will always be used as a base for further regulatory
988 		 * settings
989 		 */
990 		chan->flags = chan->orig_flags =
991 			map_regdom_flags(reg_rule->flags);
992 		chan->max_antenna_gain = chan->orig_mag =
993 			(int) MBI_TO_DBI(power_rule->max_antenna_gain);
994 		chan->max_bandwidth = KHZ_TO_MHZ(max_bandwidth);
995 		chan->max_power = chan->orig_mpwr =
996 			(int) MBM_TO_DBM(power_rule->max_eirp);
997 		return;
998 	}
999 
1000 	chan->flags = flags | map_regdom_flags(reg_rule->flags);
1001 	chan->max_antenna_gain = min(chan->orig_mag,
1002 		(int) MBI_TO_DBI(power_rule->max_antenna_gain));
1003 	chan->max_bandwidth = KHZ_TO_MHZ(max_bandwidth);
1004 	if (chan->orig_mpwr)
1005 		chan->max_power = min(chan->orig_mpwr,
1006 			(int) MBM_TO_DBM(power_rule->max_eirp));
1007 	else
1008 		chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
1009 }
1010 
1011 static void handle_band(struct wiphy *wiphy, enum ieee80211_band band)
1012 {
1013 	unsigned int i;
1014 	struct ieee80211_supported_band *sband;
1015 
1016 	BUG_ON(!wiphy->bands[band]);
1017 	sband = wiphy->bands[band];
1018 
1019 	for (i = 0; i < sband->n_channels; i++)
1020 		handle_channel(wiphy, band, i);
1021 }
1022 
1023 static bool ignore_reg_update(struct wiphy *wiphy,
1024 			      enum nl80211_reg_initiator initiator)
1025 {
1026 	if (!last_request)
1027 		return true;
1028 	if (initiator == NL80211_REGDOM_SET_BY_CORE &&
1029 		  wiphy->custom_regulatory)
1030 		return true;
1031 	/*
1032 	 * wiphy->regd will be set once the device has its own
1033 	 * desired regulatory domain set
1034 	 */
1035 	if (wiphy->strict_regulatory && !wiphy->regd &&
1036 	    !is_world_regdom(last_request->alpha2))
1037 		return true;
1038 	return false;
1039 }
1040 
1041 static void update_all_wiphy_regulatory(enum nl80211_reg_initiator initiator)
1042 {
1043 	struct cfg80211_registered_device *drv;
1044 
1045 	list_for_each_entry(drv, &cfg80211_drv_list, list)
1046 		wiphy_update_regulatory(&drv->wiphy, initiator);
1047 }
1048 
1049 static void handle_reg_beacon(struct wiphy *wiphy,
1050 			      unsigned int chan_idx,
1051 			      struct reg_beacon *reg_beacon)
1052 {
1053 #ifdef CONFIG_CFG80211_REG_DEBUG
1054 #define REG_DEBUG_BEACON_FLAG(desc) \
1055 	printk(KERN_DEBUG "cfg80211: Enabling " desc " on " \
1056 		"frequency: %d MHz (Ch %d) on %s\n", \
1057 		reg_beacon->chan.center_freq, \
1058 		ieee80211_frequency_to_channel(reg_beacon->chan.center_freq), \
1059 		wiphy_name(wiphy));
1060 #else
1061 #define REG_DEBUG_BEACON_FLAG(desc) do {} while (0)
1062 #endif
1063 	struct ieee80211_supported_band *sband;
1064 	struct ieee80211_channel *chan;
1065 
1066 	assert_cfg80211_lock();
1067 
1068 	sband = wiphy->bands[reg_beacon->chan.band];
1069 	chan = &sband->channels[chan_idx];
1070 
1071 	if (likely(chan->center_freq != reg_beacon->chan.center_freq))
1072 		return;
1073 
1074 	if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN) {
1075 		chan->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
1076 		REG_DEBUG_BEACON_FLAG("active scanning");
1077 	}
1078 
1079 	if (chan->flags & IEEE80211_CHAN_NO_IBSS) {
1080 		chan->flags &= ~IEEE80211_CHAN_NO_IBSS;
1081 		REG_DEBUG_BEACON_FLAG("beaconing");
1082 	}
1083 
1084 	chan->beacon_found = true;
1085 #undef REG_DEBUG_BEACON_FLAG
1086 }
1087 
1088 /*
1089  * Called when a scan on a wiphy finds a beacon on
1090  * new channel
1091  */
1092 static void wiphy_update_new_beacon(struct wiphy *wiphy,
1093 				    struct reg_beacon *reg_beacon)
1094 {
1095 	unsigned int i;
1096 	struct ieee80211_supported_band *sband;
1097 
1098 	assert_cfg80211_lock();
1099 
1100 	if (!wiphy->bands[reg_beacon->chan.band])
1101 		return;
1102 
1103 	sband = wiphy->bands[reg_beacon->chan.band];
1104 
1105 	for (i = 0; i < sband->n_channels; i++)
1106 		handle_reg_beacon(wiphy, i, reg_beacon);
1107 }
1108 
1109 /*
1110  * Called upon reg changes or a new wiphy is added
1111  */
1112 static void wiphy_update_beacon_reg(struct wiphy *wiphy)
1113 {
1114 	unsigned int i;
1115 	struct ieee80211_supported_band *sband;
1116 	struct reg_beacon *reg_beacon;
1117 
1118 	assert_cfg80211_lock();
1119 
1120 	if (list_empty(&reg_beacon_list))
1121 		return;
1122 
1123 	list_for_each_entry(reg_beacon, &reg_beacon_list, list) {
1124 		if (!wiphy->bands[reg_beacon->chan.band])
1125 			continue;
1126 		sband = wiphy->bands[reg_beacon->chan.band];
1127 		for (i = 0; i < sband->n_channels; i++)
1128 			handle_reg_beacon(wiphy, i, reg_beacon);
1129 	}
1130 }
1131 
1132 static bool reg_is_world_roaming(struct wiphy *wiphy)
1133 {
1134 	if (is_world_regdom(cfg80211_regdomain->alpha2) ||
1135 	    (wiphy->regd && is_world_regdom(wiphy->regd->alpha2)))
1136 		return true;
1137 	if (last_request &&
1138 	    last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1139 	    wiphy->custom_regulatory)
1140 		return true;
1141 	return false;
1142 }
1143 
1144 /* Reap the advantages of previously found beacons */
1145 static void reg_process_beacons(struct wiphy *wiphy)
1146 {
1147 	/*
1148 	 * Means we are just firing up cfg80211, so no beacons would
1149 	 * have been processed yet.
1150 	 */
1151 	if (!last_request)
1152 		return;
1153 	if (!reg_is_world_roaming(wiphy))
1154 		return;
1155 	wiphy_update_beacon_reg(wiphy);
1156 }
1157 
1158 void wiphy_update_regulatory(struct wiphy *wiphy,
1159 			     enum nl80211_reg_initiator initiator)
1160 {
1161 	enum ieee80211_band band;
1162 
1163 	if (ignore_reg_update(wiphy, initiator))
1164 		goto out;
1165 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1166 		if (wiphy->bands[band])
1167 			handle_band(wiphy, band);
1168 	}
1169 out:
1170 	reg_process_beacons(wiphy);
1171 	if (wiphy->reg_notifier)
1172 		wiphy->reg_notifier(wiphy, last_request);
1173 }
1174 
1175 static void handle_channel_custom(struct wiphy *wiphy,
1176 				  enum ieee80211_band band,
1177 				  unsigned int chan_idx,
1178 				  const struct ieee80211_regdomain *regd)
1179 {
1180 	int r;
1181 	u32 max_bandwidth = 0;
1182 	const struct ieee80211_reg_rule *reg_rule = NULL;
1183 	const struct ieee80211_power_rule *power_rule = NULL;
1184 	struct ieee80211_supported_band *sband;
1185 	struct ieee80211_channel *chan;
1186 
1187 	assert_cfg80211_lock();
1188 
1189 	sband = wiphy->bands[band];
1190 	BUG_ON(chan_idx >= sband->n_channels);
1191 	chan = &sband->channels[chan_idx];
1192 
1193 	r = freq_reg_info_regd(wiphy, MHZ_TO_KHZ(chan->center_freq),
1194 		&max_bandwidth, &reg_rule, regd);
1195 
1196 	if (r) {
1197 		chan->flags = IEEE80211_CHAN_DISABLED;
1198 		return;
1199 	}
1200 
1201 	power_rule = &reg_rule->power_rule;
1202 
1203 	chan->flags |= map_regdom_flags(reg_rule->flags);
1204 	chan->max_antenna_gain = (int) MBI_TO_DBI(power_rule->max_antenna_gain);
1205 	chan->max_bandwidth = KHZ_TO_MHZ(max_bandwidth);
1206 	chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
1207 }
1208 
1209 static void handle_band_custom(struct wiphy *wiphy, enum ieee80211_band band,
1210 			       const struct ieee80211_regdomain *regd)
1211 {
1212 	unsigned int i;
1213 	struct ieee80211_supported_band *sband;
1214 
1215 	BUG_ON(!wiphy->bands[band]);
1216 	sband = wiphy->bands[band];
1217 
1218 	for (i = 0; i < sband->n_channels; i++)
1219 		handle_channel_custom(wiphy, band, i, regd);
1220 }
1221 
1222 /* Used by drivers prior to wiphy registration */
1223 void wiphy_apply_custom_regulatory(struct wiphy *wiphy,
1224 				   const struct ieee80211_regdomain *regd)
1225 {
1226 	enum ieee80211_band band;
1227 
1228 	mutex_lock(&cfg80211_mutex);
1229 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1230 		if (wiphy->bands[band])
1231 			handle_band_custom(wiphy, band, regd);
1232 	}
1233 	mutex_unlock(&cfg80211_mutex);
1234 }
1235 EXPORT_SYMBOL(wiphy_apply_custom_regulatory);
1236 
1237 static int reg_copy_regd(const struct ieee80211_regdomain **dst_regd,
1238 			 const struct ieee80211_regdomain *src_regd)
1239 {
1240 	struct ieee80211_regdomain *regd;
1241 	int size_of_regd = 0;
1242 	unsigned int i;
1243 
1244 	size_of_regd = sizeof(struct ieee80211_regdomain) +
1245 	  ((src_regd->n_reg_rules + 1) * sizeof(struct ieee80211_reg_rule));
1246 
1247 	regd = kzalloc(size_of_regd, GFP_KERNEL);
1248 	if (!regd)
1249 		return -ENOMEM;
1250 
1251 	memcpy(regd, src_regd, sizeof(struct ieee80211_regdomain));
1252 
1253 	for (i = 0; i < src_regd->n_reg_rules; i++)
1254 		memcpy(&regd->reg_rules[i], &src_regd->reg_rules[i],
1255 			sizeof(struct ieee80211_reg_rule));
1256 
1257 	*dst_regd = regd;
1258 	return 0;
1259 }
1260 
1261 /*
1262  * Return value which can be used by ignore_request() to indicate
1263  * it has been determined we should intersect two regulatory domains
1264  */
1265 #define REG_INTERSECT	1
1266 
1267 /* This has the logic which determines when a new request
1268  * should be ignored. */
1269 static int ignore_request(struct wiphy *wiphy,
1270 			  struct regulatory_request *pending_request)
1271 {
1272 	struct wiphy *last_wiphy = NULL;
1273 
1274 	assert_cfg80211_lock();
1275 
1276 	/* All initial requests are respected */
1277 	if (!last_request)
1278 		return 0;
1279 
1280 	switch (pending_request->initiator) {
1281 	case NL80211_REGDOM_SET_BY_CORE:
1282 		return -EINVAL;
1283 	case NL80211_REGDOM_SET_BY_COUNTRY_IE:
1284 
1285 		last_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
1286 
1287 		if (unlikely(!is_an_alpha2(pending_request->alpha2)))
1288 			return -EINVAL;
1289 		if (last_request->initiator ==
1290 		    NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1291 			if (last_wiphy != wiphy) {
1292 				/*
1293 				 * Two cards with two APs claiming different
1294 				 * different Country IE alpha2s. We could
1295 				 * intersect them, but that seems unlikely
1296 				 * to be correct. Reject second one for now.
1297 				 */
1298 				if (regdom_changes(pending_request->alpha2))
1299 					return -EOPNOTSUPP;
1300 				return -EALREADY;
1301 			}
1302 			/*
1303 			 * Two consecutive Country IE hints on the same wiphy.
1304 			 * This should be picked up early by the driver/stack
1305 			 */
1306 			if (WARN_ON(regdom_changes(pending_request->alpha2)))
1307 				return 0;
1308 			return -EALREADY;
1309 		}
1310 		return REG_INTERSECT;
1311 	case NL80211_REGDOM_SET_BY_DRIVER:
1312 		if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE) {
1313 			if (is_old_static_regdom(cfg80211_regdomain))
1314 				return 0;
1315 			if (regdom_changes(pending_request->alpha2))
1316 				return 0;
1317 			return -EALREADY;
1318 		}
1319 
1320 		/*
1321 		 * This would happen if you unplug and plug your card
1322 		 * back in or if you add a new device for which the previously
1323 		 * loaded card also agrees on the regulatory domain.
1324 		 */
1325 		if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1326 		    !regdom_changes(pending_request->alpha2))
1327 			return -EALREADY;
1328 
1329 		return REG_INTERSECT;
1330 	case NL80211_REGDOM_SET_BY_USER:
1331 		if (last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE)
1332 			return REG_INTERSECT;
1333 		/*
1334 		 * If the user knows better the user should set the regdom
1335 		 * to their country before the IE is picked up
1336 		 */
1337 		if (last_request->initiator == NL80211_REGDOM_SET_BY_USER &&
1338 			  last_request->intersect)
1339 			return -EOPNOTSUPP;
1340 		/*
1341 		 * Process user requests only after previous user/driver/core
1342 		 * requests have been processed
1343 		 */
1344 		if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE ||
1345 		    last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER ||
1346 		    last_request->initiator == NL80211_REGDOM_SET_BY_USER) {
1347 			if (regdom_changes(last_request->alpha2))
1348 				return -EAGAIN;
1349 		}
1350 
1351 		if (!is_old_static_regdom(cfg80211_regdomain) &&
1352 		    !regdom_changes(pending_request->alpha2))
1353 			return -EALREADY;
1354 
1355 		return 0;
1356 	}
1357 
1358 	return -EINVAL;
1359 }
1360 
1361 /**
1362  * __regulatory_hint - hint to the wireless core a regulatory domain
1363  * @wiphy: if the hint comes from country information from an AP, this
1364  *	is required to be set to the wiphy that received the information
1365  * @pending_request: the regulatory request currently being processed
1366  *
1367  * The Wireless subsystem can use this function to hint to the wireless core
1368  * what it believes should be the current regulatory domain.
1369  *
1370  * Returns zero if all went fine, %-EALREADY if a regulatory domain had
1371  * already been set or other standard error codes.
1372  *
1373  * Caller must hold &cfg80211_mutex
1374  */
1375 static int __regulatory_hint(struct wiphy *wiphy,
1376 			     struct regulatory_request *pending_request)
1377 {
1378 	bool intersect = false;
1379 	int r = 0;
1380 
1381 	assert_cfg80211_lock();
1382 
1383 	r = ignore_request(wiphy, pending_request);
1384 
1385 	if (r == REG_INTERSECT) {
1386 		if (pending_request->initiator ==
1387 		    NL80211_REGDOM_SET_BY_DRIVER) {
1388 			r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1389 			if (r) {
1390 				kfree(pending_request);
1391 				return r;
1392 			}
1393 		}
1394 		intersect = true;
1395 	} else if (r) {
1396 		/*
1397 		 * If the regulatory domain being requested by the
1398 		 * driver has already been set just copy it to the
1399 		 * wiphy
1400 		 */
1401 		if (r == -EALREADY &&
1402 		    pending_request->initiator ==
1403 		    NL80211_REGDOM_SET_BY_DRIVER) {
1404 			r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1405 			if (r) {
1406 				kfree(pending_request);
1407 				return r;
1408 			}
1409 			r = -EALREADY;
1410 			goto new_request;
1411 		}
1412 		kfree(pending_request);
1413 		return r;
1414 	}
1415 
1416 new_request:
1417 	kfree(last_request);
1418 
1419 	last_request = pending_request;
1420 	last_request->intersect = intersect;
1421 
1422 	pending_request = NULL;
1423 
1424 	/* When r == REG_INTERSECT we do need to call CRDA */
1425 	if (r < 0) {
1426 		/*
1427 		 * Since CRDA will not be called in this case as we already
1428 		 * have applied the requested regulatory domain before we just
1429 		 * inform userspace we have processed the request
1430 		 */
1431 		if (r == -EALREADY)
1432 			nl80211_send_reg_change_event(last_request);
1433 		return r;
1434 	}
1435 
1436 	return call_crda(last_request->alpha2);
1437 }
1438 
1439 /* This processes *all* regulatory hints */
1440 static void reg_process_hint(struct regulatory_request *reg_request)
1441 {
1442 	int r = 0;
1443 	struct wiphy *wiphy = NULL;
1444 
1445 	BUG_ON(!reg_request->alpha2);
1446 
1447 	mutex_lock(&cfg80211_mutex);
1448 
1449 	if (wiphy_idx_valid(reg_request->wiphy_idx))
1450 		wiphy = wiphy_idx_to_wiphy(reg_request->wiphy_idx);
1451 
1452 	if (reg_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1453 	    !wiphy) {
1454 		kfree(reg_request);
1455 		goto out;
1456 	}
1457 
1458 	r = __regulatory_hint(wiphy, reg_request);
1459 	/* This is required so that the orig_* parameters are saved */
1460 	if (r == -EALREADY && wiphy && wiphy->strict_regulatory)
1461 		wiphy_update_regulatory(wiphy, reg_request->initiator);
1462 out:
1463 	mutex_unlock(&cfg80211_mutex);
1464 }
1465 
1466 /* Processes regulatory hints, this is all the NL80211_REGDOM_SET_BY_* */
1467 static void reg_process_pending_hints(void)
1468 	{
1469 	struct regulatory_request *reg_request;
1470 
1471 	spin_lock(&reg_requests_lock);
1472 	while (!list_empty(&reg_requests_list)) {
1473 		reg_request = list_first_entry(&reg_requests_list,
1474 					       struct regulatory_request,
1475 					       list);
1476 		list_del_init(&reg_request->list);
1477 
1478 		spin_unlock(&reg_requests_lock);
1479 		reg_process_hint(reg_request);
1480 		spin_lock(&reg_requests_lock);
1481 	}
1482 	spin_unlock(&reg_requests_lock);
1483 }
1484 
1485 /* Processes beacon hints -- this has nothing to do with country IEs */
1486 static void reg_process_pending_beacon_hints(void)
1487 {
1488 	struct cfg80211_registered_device *drv;
1489 	struct reg_beacon *pending_beacon, *tmp;
1490 
1491 	mutex_lock(&cfg80211_mutex);
1492 
1493 	/* This goes through the _pending_ beacon list */
1494 	spin_lock_bh(&reg_pending_beacons_lock);
1495 
1496 	if (list_empty(&reg_pending_beacons)) {
1497 		spin_unlock_bh(&reg_pending_beacons_lock);
1498 		goto out;
1499 	}
1500 
1501 	list_for_each_entry_safe(pending_beacon, tmp,
1502 				 &reg_pending_beacons, list) {
1503 
1504 		list_del_init(&pending_beacon->list);
1505 
1506 		/* Applies the beacon hint to current wiphys */
1507 		list_for_each_entry(drv, &cfg80211_drv_list, list)
1508 			wiphy_update_new_beacon(&drv->wiphy, pending_beacon);
1509 
1510 		/* Remembers the beacon hint for new wiphys or reg changes */
1511 		list_add_tail(&pending_beacon->list, &reg_beacon_list);
1512 	}
1513 
1514 	spin_unlock_bh(&reg_pending_beacons_lock);
1515 out:
1516 	mutex_unlock(&cfg80211_mutex);
1517 }
1518 
1519 static void reg_todo(struct work_struct *work)
1520 {
1521 	reg_process_pending_hints();
1522 	reg_process_pending_beacon_hints();
1523 }
1524 
1525 static DECLARE_WORK(reg_work, reg_todo);
1526 
1527 static void queue_regulatory_request(struct regulatory_request *request)
1528 {
1529 	spin_lock(&reg_requests_lock);
1530 	list_add_tail(&request->list, &reg_requests_list);
1531 	spin_unlock(&reg_requests_lock);
1532 
1533 	schedule_work(&reg_work);
1534 }
1535 
1536 /* Core regulatory hint -- happens once during cfg80211_init() */
1537 static int regulatory_hint_core(const char *alpha2)
1538 {
1539 	struct regulatory_request *request;
1540 
1541 	BUG_ON(last_request);
1542 
1543 	request = kzalloc(sizeof(struct regulatory_request),
1544 			  GFP_KERNEL);
1545 	if (!request)
1546 		return -ENOMEM;
1547 
1548 	request->alpha2[0] = alpha2[0];
1549 	request->alpha2[1] = alpha2[1];
1550 	request->initiator = NL80211_REGDOM_SET_BY_CORE;
1551 
1552 	queue_regulatory_request(request);
1553 
1554 	return 0;
1555 }
1556 
1557 /* User hints */
1558 int regulatory_hint_user(const char *alpha2)
1559 {
1560 	struct regulatory_request *request;
1561 
1562 	BUG_ON(!alpha2);
1563 
1564 	request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1565 	if (!request)
1566 		return -ENOMEM;
1567 
1568 	request->wiphy_idx = WIPHY_IDX_STALE;
1569 	request->alpha2[0] = alpha2[0];
1570 	request->alpha2[1] = alpha2[1];
1571 	request->initiator = NL80211_REGDOM_SET_BY_USER,
1572 
1573 	queue_regulatory_request(request);
1574 
1575 	return 0;
1576 }
1577 
1578 /* Driver hints */
1579 int regulatory_hint(struct wiphy *wiphy, const char *alpha2)
1580 {
1581 	struct regulatory_request *request;
1582 
1583 	BUG_ON(!alpha2);
1584 	BUG_ON(!wiphy);
1585 
1586 	request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1587 	if (!request)
1588 		return -ENOMEM;
1589 
1590 	request->wiphy_idx = get_wiphy_idx(wiphy);
1591 
1592 	/* Must have registered wiphy first */
1593 	BUG_ON(!wiphy_idx_valid(request->wiphy_idx));
1594 
1595 	request->alpha2[0] = alpha2[0];
1596 	request->alpha2[1] = alpha2[1];
1597 	request->initiator = NL80211_REGDOM_SET_BY_DRIVER;
1598 
1599 	queue_regulatory_request(request);
1600 
1601 	return 0;
1602 }
1603 EXPORT_SYMBOL(regulatory_hint);
1604 
1605 static bool reg_same_country_ie_hint(struct wiphy *wiphy,
1606 			u32 country_ie_checksum)
1607 {
1608 	struct wiphy *request_wiphy;
1609 
1610 	assert_cfg80211_lock();
1611 
1612 	if (unlikely(last_request->initiator !=
1613 	    NL80211_REGDOM_SET_BY_COUNTRY_IE))
1614 		return false;
1615 
1616 	request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
1617 
1618 	if (!request_wiphy)
1619 		return false;
1620 
1621 	if (likely(request_wiphy != wiphy))
1622 		return !country_ie_integrity_changes(country_ie_checksum);
1623 	/*
1624 	 * We should not have let these through at this point, they
1625 	 * should have been picked up earlier by the first alpha2 check
1626 	 * on the device
1627 	 */
1628 	if (WARN_ON(!country_ie_integrity_changes(country_ie_checksum)))
1629 		return true;
1630 	return false;
1631 }
1632 
1633 void regulatory_hint_11d(struct wiphy *wiphy,
1634 			u8 *country_ie,
1635 			u8 country_ie_len)
1636 {
1637 	struct ieee80211_regdomain *rd = NULL;
1638 	char alpha2[2];
1639 	u32 checksum = 0;
1640 	enum environment_cap env = ENVIRON_ANY;
1641 	struct regulatory_request *request;
1642 
1643 	mutex_lock(&cfg80211_mutex);
1644 
1645 	if (unlikely(!last_request)) {
1646 		mutex_unlock(&cfg80211_mutex);
1647 		return;
1648 	}
1649 
1650 	/* IE len must be evenly divisible by 2 */
1651 	if (country_ie_len & 0x01)
1652 		goto out;
1653 
1654 	if (country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN)
1655 		goto out;
1656 
1657 	/*
1658 	 * Pending country IE processing, this can happen after we
1659 	 * call CRDA and wait for a response if a beacon was received before
1660 	 * we were able to process the last regulatory_hint_11d() call
1661 	 */
1662 	if (country_ie_regdomain)
1663 		goto out;
1664 
1665 	alpha2[0] = country_ie[0];
1666 	alpha2[1] = country_ie[1];
1667 
1668 	if (country_ie[2] == 'I')
1669 		env = ENVIRON_INDOOR;
1670 	else if (country_ie[2] == 'O')
1671 		env = ENVIRON_OUTDOOR;
1672 
1673 	/*
1674 	 * We will run this for *every* beacon processed for the BSSID, so
1675 	 * we optimize an early check to exit out early if we don't have to
1676 	 * do anything
1677 	 */
1678 	if (likely(last_request->initiator ==
1679 	    NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1680 	    wiphy_idx_valid(last_request->wiphy_idx))) {
1681 		struct cfg80211_registered_device *drv_last_ie;
1682 
1683 		drv_last_ie =
1684 			cfg80211_drv_by_wiphy_idx(last_request->wiphy_idx);
1685 
1686 		/*
1687 		 * Lets keep this simple -- we trust the first AP
1688 		 * after we intersect with CRDA
1689 		 */
1690 		if (likely(&drv_last_ie->wiphy == wiphy)) {
1691 			/*
1692 			 * Ignore IEs coming in on this wiphy with
1693 			 * the same alpha2 and environment cap
1694 			 */
1695 			if (likely(alpha2_equal(drv_last_ie->country_ie_alpha2,
1696 				  alpha2) &&
1697 				  env == drv_last_ie->env)) {
1698 				goto out;
1699 			}
1700 			/*
1701 			 * the wiphy moved on to another BSSID or the AP
1702 			 * was reconfigured. XXX: We need to deal with the
1703 			 * case where the user suspends and goes to goes
1704 			 * to another country, and then gets IEs from an
1705 			 * AP with different settings
1706 			 */
1707 			goto out;
1708 		} else {
1709 			/*
1710 			 * Ignore IEs coming in on two separate wiphys with
1711 			 * the same alpha2 and environment cap
1712 			 */
1713 			if (likely(alpha2_equal(drv_last_ie->country_ie_alpha2,
1714 				  alpha2) &&
1715 				  env == drv_last_ie->env)) {
1716 				goto out;
1717 			}
1718 			/* We could potentially intersect though */
1719 			goto out;
1720 		}
1721 	}
1722 
1723 	rd = country_ie_2_rd(country_ie, country_ie_len, &checksum);
1724 	if (!rd)
1725 		goto out;
1726 
1727 	/*
1728 	 * This will not happen right now but we leave it here for the
1729 	 * the future when we want to add suspend/resume support and having
1730 	 * the user move to another country after doing so, or having the user
1731 	 * move to another AP. Right now we just trust the first AP.
1732 	 *
1733 	 * If we hit this before we add this support we want to be informed of
1734 	 * it as it would indicate a mistake in the current design
1735 	 */
1736 	if (WARN_ON(reg_same_country_ie_hint(wiphy, checksum)))
1737 		goto free_rd_out;
1738 
1739 	request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1740 	if (!request)
1741 		goto free_rd_out;
1742 
1743 	/*
1744 	 * We keep this around for when CRDA comes back with a response so
1745 	 * we can intersect with that
1746 	 */
1747 	country_ie_regdomain = rd;
1748 
1749 	request->wiphy_idx = get_wiphy_idx(wiphy);
1750 	request->alpha2[0] = rd->alpha2[0];
1751 	request->alpha2[1] = rd->alpha2[1];
1752 	request->initiator = NL80211_REGDOM_SET_BY_COUNTRY_IE;
1753 	request->country_ie_checksum = checksum;
1754 	request->country_ie_env = env;
1755 
1756 	mutex_unlock(&cfg80211_mutex);
1757 
1758 	queue_regulatory_request(request);
1759 
1760 	return;
1761 
1762 free_rd_out:
1763 	kfree(rd);
1764 out:
1765 	mutex_unlock(&cfg80211_mutex);
1766 }
1767 EXPORT_SYMBOL(regulatory_hint_11d);
1768 
1769 static bool freq_is_chan_12_13_14(u16 freq)
1770 {
1771 	if (freq == ieee80211_channel_to_frequency(12) ||
1772 	    freq == ieee80211_channel_to_frequency(13) ||
1773 	    freq == ieee80211_channel_to_frequency(14))
1774 		return true;
1775 	return false;
1776 }
1777 
1778 int regulatory_hint_found_beacon(struct wiphy *wiphy,
1779 				 struct ieee80211_channel *beacon_chan,
1780 				 gfp_t gfp)
1781 {
1782 	struct reg_beacon *reg_beacon;
1783 
1784 	if (likely((beacon_chan->beacon_found ||
1785 	    (beacon_chan->flags & IEEE80211_CHAN_RADAR) ||
1786 	    (beacon_chan->band == IEEE80211_BAND_2GHZ &&
1787 	     !freq_is_chan_12_13_14(beacon_chan->center_freq)))))
1788 		return 0;
1789 
1790 	reg_beacon = kzalloc(sizeof(struct reg_beacon), gfp);
1791 	if (!reg_beacon)
1792 		return -ENOMEM;
1793 
1794 #ifdef CONFIG_CFG80211_REG_DEBUG
1795 	printk(KERN_DEBUG "cfg80211: Found new beacon on "
1796 		"frequency: %d MHz (Ch %d) on %s\n",
1797 		beacon_chan->center_freq,
1798 		ieee80211_frequency_to_channel(beacon_chan->center_freq),
1799 		wiphy_name(wiphy));
1800 #endif
1801 	memcpy(&reg_beacon->chan, beacon_chan,
1802 		sizeof(struct ieee80211_channel));
1803 
1804 
1805 	/*
1806 	 * Since we can be called from BH or and non-BH context
1807 	 * we must use spin_lock_bh()
1808 	 */
1809 	spin_lock_bh(&reg_pending_beacons_lock);
1810 	list_add_tail(&reg_beacon->list, &reg_pending_beacons);
1811 	spin_unlock_bh(&reg_pending_beacons_lock);
1812 
1813 	schedule_work(&reg_work);
1814 
1815 	return 0;
1816 }
1817 
1818 static void print_rd_rules(const struct ieee80211_regdomain *rd)
1819 {
1820 	unsigned int i;
1821 	const struct ieee80211_reg_rule *reg_rule = NULL;
1822 	const struct ieee80211_freq_range *freq_range = NULL;
1823 	const struct ieee80211_power_rule *power_rule = NULL;
1824 
1825 	printk(KERN_INFO "\t(start_freq - end_freq @ bandwidth), "
1826 		"(max_antenna_gain, max_eirp)\n");
1827 
1828 	for (i = 0; i < rd->n_reg_rules; i++) {
1829 		reg_rule = &rd->reg_rules[i];
1830 		freq_range = &reg_rule->freq_range;
1831 		power_rule = &reg_rule->power_rule;
1832 
1833 		/*
1834 		 * There may not be documentation for max antenna gain
1835 		 * in certain regions
1836 		 */
1837 		if (power_rule->max_antenna_gain)
1838 			printk(KERN_INFO "\t(%d KHz - %d KHz @ %d KHz), "
1839 				"(%d mBi, %d mBm)\n",
1840 				freq_range->start_freq_khz,
1841 				freq_range->end_freq_khz,
1842 				freq_range->max_bandwidth_khz,
1843 				power_rule->max_antenna_gain,
1844 				power_rule->max_eirp);
1845 		else
1846 			printk(KERN_INFO "\t(%d KHz - %d KHz @ %d KHz), "
1847 				"(N/A, %d mBm)\n",
1848 				freq_range->start_freq_khz,
1849 				freq_range->end_freq_khz,
1850 				freq_range->max_bandwidth_khz,
1851 				power_rule->max_eirp);
1852 	}
1853 }
1854 
1855 static void print_regdomain(const struct ieee80211_regdomain *rd)
1856 {
1857 
1858 	if (is_intersected_alpha2(rd->alpha2)) {
1859 
1860 		if (last_request->initiator ==
1861 		    NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1862 			struct cfg80211_registered_device *drv;
1863 			drv = cfg80211_drv_by_wiphy_idx(
1864 				last_request->wiphy_idx);
1865 			if (drv) {
1866 				printk(KERN_INFO "cfg80211: Current regulatory "
1867 					"domain updated by AP to: %c%c\n",
1868 					drv->country_ie_alpha2[0],
1869 					drv->country_ie_alpha2[1]);
1870 			} else
1871 				printk(KERN_INFO "cfg80211: Current regulatory "
1872 					"domain intersected: \n");
1873 		} else
1874 				printk(KERN_INFO "cfg80211: Current regulatory "
1875 					"domain intersected: \n");
1876 	} else if (is_world_regdom(rd->alpha2))
1877 		printk(KERN_INFO "cfg80211: World regulatory "
1878 			"domain updated:\n");
1879 	else {
1880 		if (is_unknown_alpha2(rd->alpha2))
1881 			printk(KERN_INFO "cfg80211: Regulatory domain "
1882 				"changed to driver built-in settings "
1883 				"(unknown country)\n");
1884 		else
1885 			printk(KERN_INFO "cfg80211: Regulatory domain "
1886 				"changed to country: %c%c\n",
1887 				rd->alpha2[0], rd->alpha2[1]);
1888 	}
1889 	print_rd_rules(rd);
1890 }
1891 
1892 static void print_regdomain_info(const struct ieee80211_regdomain *rd)
1893 {
1894 	printk(KERN_INFO "cfg80211: Regulatory domain: %c%c\n",
1895 		rd->alpha2[0], rd->alpha2[1]);
1896 	print_rd_rules(rd);
1897 }
1898 
1899 #ifdef CONFIG_CFG80211_REG_DEBUG
1900 static void reg_country_ie_process_debug(
1901 	const struct ieee80211_regdomain *rd,
1902 	const struct ieee80211_regdomain *country_ie_regdomain,
1903 	const struct ieee80211_regdomain *intersected_rd)
1904 {
1905 	printk(KERN_DEBUG "cfg80211: Received country IE:\n");
1906 	print_regdomain_info(country_ie_regdomain);
1907 	printk(KERN_DEBUG "cfg80211: CRDA thinks this should applied:\n");
1908 	print_regdomain_info(rd);
1909 	if (intersected_rd) {
1910 		printk(KERN_DEBUG "cfg80211: We intersect both of these "
1911 			"and get:\n");
1912 		print_regdomain_info(intersected_rd);
1913 		return;
1914 	}
1915 	printk(KERN_DEBUG "cfg80211: Intersection between both failed\n");
1916 }
1917 #else
1918 static inline void reg_country_ie_process_debug(
1919 	const struct ieee80211_regdomain *rd,
1920 	const struct ieee80211_regdomain *country_ie_regdomain,
1921 	const struct ieee80211_regdomain *intersected_rd)
1922 {
1923 }
1924 #endif
1925 
1926 /* Takes ownership of rd only if it doesn't fail */
1927 static int __set_regdom(const struct ieee80211_regdomain *rd)
1928 {
1929 	const struct ieee80211_regdomain *intersected_rd = NULL;
1930 	struct cfg80211_registered_device *drv = NULL;
1931 	struct wiphy *request_wiphy;
1932 	/* Some basic sanity checks first */
1933 
1934 	if (is_world_regdom(rd->alpha2)) {
1935 		if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
1936 			return -EINVAL;
1937 		update_world_regdomain(rd);
1938 		return 0;
1939 	}
1940 
1941 	if (!is_alpha2_set(rd->alpha2) && !is_an_alpha2(rd->alpha2) &&
1942 			!is_unknown_alpha2(rd->alpha2))
1943 		return -EINVAL;
1944 
1945 	if (!last_request)
1946 		return -EINVAL;
1947 
1948 	/*
1949 	 * Lets only bother proceeding on the same alpha2 if the current
1950 	 * rd is non static (it means CRDA was present and was used last)
1951 	 * and the pending request came in from a country IE
1952 	 */
1953 	if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1954 		/*
1955 		 * If someone else asked us to change the rd lets only bother
1956 		 * checking if the alpha2 changes if CRDA was already called
1957 		 */
1958 		if (!is_old_static_regdom(cfg80211_regdomain) &&
1959 		    !regdom_changes(rd->alpha2))
1960 			return -EINVAL;
1961 	}
1962 
1963 	/*
1964 	 * Now lets set the regulatory domain, update all driver channels
1965 	 * and finally inform them of what we have done, in case they want
1966 	 * to review or adjust their own settings based on their own
1967 	 * internal EEPROM data
1968 	 */
1969 
1970 	if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
1971 		return -EINVAL;
1972 
1973 	if (!is_valid_rd(rd)) {
1974 		printk(KERN_ERR "cfg80211: Invalid "
1975 			"regulatory domain detected:\n");
1976 		print_regdomain_info(rd);
1977 		return -EINVAL;
1978 	}
1979 
1980 	request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
1981 
1982 	if (!last_request->intersect) {
1983 		int r;
1984 
1985 		if (last_request->initiator != NL80211_REGDOM_SET_BY_DRIVER) {
1986 			reset_regdomains();
1987 			cfg80211_regdomain = rd;
1988 			return 0;
1989 		}
1990 
1991 		/*
1992 		 * For a driver hint, lets copy the regulatory domain the
1993 		 * driver wanted to the wiphy to deal with conflicts
1994 		 */
1995 
1996 		BUG_ON(request_wiphy->regd);
1997 
1998 		r = reg_copy_regd(&request_wiphy->regd, rd);
1999 		if (r)
2000 			return r;
2001 
2002 		reset_regdomains();
2003 		cfg80211_regdomain = rd;
2004 		return 0;
2005 	}
2006 
2007 	/* Intersection requires a bit more work */
2008 
2009 	if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2010 
2011 		intersected_rd = regdom_intersect(rd, cfg80211_regdomain);
2012 		if (!intersected_rd)
2013 			return -EINVAL;
2014 
2015 		/*
2016 		 * We can trash what CRDA provided now.
2017 		 * However if a driver requested this specific regulatory
2018 		 * domain we keep it for its private use
2019 		 */
2020 		if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER)
2021 			request_wiphy->regd = rd;
2022 		else
2023 			kfree(rd);
2024 
2025 		rd = NULL;
2026 
2027 		reset_regdomains();
2028 		cfg80211_regdomain = intersected_rd;
2029 
2030 		return 0;
2031 	}
2032 
2033 	/*
2034 	 * Country IE requests are handled a bit differently, we intersect
2035 	 * the country IE rd with what CRDA believes that country should have
2036 	 */
2037 
2038 	BUG_ON(!country_ie_regdomain);
2039 	BUG_ON(rd == country_ie_regdomain);
2040 
2041 	/*
2042 	 * Intersect what CRDA returned and our what we
2043 	 * had built from the Country IE received
2044 	 */
2045 
2046 	intersected_rd = regdom_intersect(rd, country_ie_regdomain);
2047 
2048 	reg_country_ie_process_debug(rd,
2049 				     country_ie_regdomain,
2050 				     intersected_rd);
2051 
2052 	kfree(country_ie_regdomain);
2053 	country_ie_regdomain = NULL;
2054 
2055 	if (!intersected_rd)
2056 		return -EINVAL;
2057 
2058 	drv = wiphy_to_dev(request_wiphy);
2059 
2060 	drv->country_ie_alpha2[0] = rd->alpha2[0];
2061 	drv->country_ie_alpha2[1] = rd->alpha2[1];
2062 	drv->env = last_request->country_ie_env;
2063 
2064 	BUG_ON(intersected_rd == rd);
2065 
2066 	kfree(rd);
2067 	rd = NULL;
2068 
2069 	reset_regdomains();
2070 	cfg80211_regdomain = intersected_rd;
2071 
2072 	return 0;
2073 }
2074 
2075 
2076 /*
2077  * Use this call to set the current regulatory domain. Conflicts with
2078  * multiple drivers can be ironed out later. Caller must've already
2079  * kmalloc'd the rd structure. Caller must hold cfg80211_mutex
2080  */
2081 int set_regdom(const struct ieee80211_regdomain *rd)
2082 {
2083 	int r;
2084 
2085 	assert_cfg80211_lock();
2086 
2087 	/* Note that this doesn't update the wiphys, this is done below */
2088 	r = __set_regdom(rd);
2089 	if (r) {
2090 		kfree(rd);
2091 		return r;
2092 	}
2093 
2094 	/* This would make this whole thing pointless */
2095 	if (!last_request->intersect)
2096 		BUG_ON(rd != cfg80211_regdomain);
2097 
2098 	/* update all wiphys now with the new established regulatory domain */
2099 	update_all_wiphy_regulatory(last_request->initiator);
2100 
2101 	print_regdomain(cfg80211_regdomain);
2102 
2103 	nl80211_send_reg_change_event(last_request);
2104 
2105 	return r;
2106 }
2107 
2108 /* Caller must hold cfg80211_mutex */
2109 void reg_device_remove(struct wiphy *wiphy)
2110 {
2111 	struct wiphy *request_wiphy = NULL;
2112 
2113 	assert_cfg80211_lock();
2114 
2115 	if (last_request)
2116 		request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
2117 
2118 	kfree(wiphy->regd);
2119 	if (!last_request || !request_wiphy)
2120 		return;
2121 	if (request_wiphy != wiphy)
2122 		return;
2123 	last_request->wiphy_idx = WIPHY_IDX_STALE;
2124 	last_request->country_ie_env = ENVIRON_ANY;
2125 }
2126 
2127 int regulatory_init(void)
2128 {
2129 	int err = 0;
2130 
2131 	reg_pdev = platform_device_register_simple("regulatory", 0, NULL, 0);
2132 	if (IS_ERR(reg_pdev))
2133 		return PTR_ERR(reg_pdev);
2134 
2135 	spin_lock_init(&reg_requests_lock);
2136 	spin_lock_init(&reg_pending_beacons_lock);
2137 
2138 #ifdef CONFIG_WIRELESS_OLD_REGULATORY
2139 	cfg80211_regdomain = static_regdom(ieee80211_regdom);
2140 
2141 	printk(KERN_INFO "cfg80211: Using static regulatory domain info\n");
2142 	print_regdomain_info(cfg80211_regdomain);
2143 	/*
2144 	 * The old code still requests for a new regdomain and if
2145 	 * you have CRDA you get it updated, otherwise you get
2146 	 * stuck with the static values. Since "EU" is not a valid
2147 	 * ISO / IEC 3166 alpha2 code we can't expect userpace to
2148 	 * give us a regulatory domain for it. We need last_request
2149 	 * iniitalized though so lets just send a request which we
2150 	 * know will be ignored... this crap will be removed once
2151 	 * OLD_REG dies.
2152 	 */
2153 	err = regulatory_hint_core(ieee80211_regdom);
2154 #else
2155 	cfg80211_regdomain = cfg80211_world_regdom;
2156 
2157 	err = regulatory_hint_core(ieee80211_regdom);
2158 #endif
2159 	if (err) {
2160 		if (err == -ENOMEM)
2161 			return err;
2162 		/*
2163 		 * N.B. kobject_uevent_env() can fail mainly for when we're out
2164 		 * memory which is handled and propagated appropriately above
2165 		 * but it can also fail during a netlink_broadcast() or during
2166 		 * early boot for call_usermodehelper(). For now treat these
2167 		 * errors as non-fatal.
2168 		 */
2169 		printk(KERN_ERR "cfg80211: kobject_uevent_env() was unable "
2170 			"to call CRDA during init");
2171 #ifdef CONFIG_CFG80211_REG_DEBUG
2172 		/* We want to find out exactly why when debugging */
2173 		WARN_ON(err);
2174 #endif
2175 	}
2176 
2177 	return 0;
2178 }
2179 
2180 void regulatory_exit(void)
2181 {
2182 	struct regulatory_request *reg_request, *tmp;
2183 	struct reg_beacon *reg_beacon, *btmp;
2184 
2185 	cancel_work_sync(&reg_work);
2186 
2187 	mutex_lock(&cfg80211_mutex);
2188 
2189 	reset_regdomains();
2190 
2191 	kfree(country_ie_regdomain);
2192 	country_ie_regdomain = NULL;
2193 
2194 	kfree(last_request);
2195 
2196 	platform_device_unregister(reg_pdev);
2197 
2198 	spin_lock_bh(&reg_pending_beacons_lock);
2199 	if (!list_empty(&reg_pending_beacons)) {
2200 		list_for_each_entry_safe(reg_beacon, btmp,
2201 					 &reg_pending_beacons, list) {
2202 			list_del(&reg_beacon->list);
2203 			kfree(reg_beacon);
2204 		}
2205 	}
2206 	spin_unlock_bh(&reg_pending_beacons_lock);
2207 
2208 	if (!list_empty(&reg_beacon_list)) {
2209 		list_for_each_entry_safe(reg_beacon, btmp,
2210 					 &reg_beacon_list, list) {
2211 			list_del(&reg_beacon->list);
2212 			kfree(reg_beacon);
2213 		}
2214 	}
2215 
2216 	spin_lock(&reg_requests_lock);
2217 	if (!list_empty(&reg_requests_list)) {
2218 		list_for_each_entry_safe(reg_request, tmp,
2219 					 &reg_requests_list, list) {
2220 			list_del(&reg_request->list);
2221 			kfree(reg_request);
2222 		}
2223 	}
2224 	spin_unlock(&reg_requests_lock);
2225 
2226 	mutex_unlock(&cfg80211_mutex);
2227 }
2228