47d505616a4b04433bb9665535567bb4281938b2
[safe/jmp/linux-2.6] / net / wireless / reg.c
1 /*
2  * Copyright 2002-2005, Instant802 Networks, Inc.
3  * Copyright 2005-2006, Devicescape Software, Inc.
4  * Copyright 2007       Johannes Berg <johannes@sipsolutions.net>
5  * Copyright 2008       Luis R. Rodriguez <lrodriguz@atheros.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11
12 /**
13  * DOC: Wireless regulatory infrastructure
14  *
15  * The usual implementation is for a driver to read a device EEPROM to
16  * determine which regulatory domain it should be operating under, then
17  * looking up the allowable channels in a driver-local table and finally
18  * registering those channels in the wiphy structure.
19  *
20  * Another set of compliance enforcement is for drivers to use their
21  * own compliance limits which can be stored on the EEPROM. The host
22  * driver or firmware may ensure these are used.
23  *
24  * In addition to all this we provide an extra layer of regulatory
25  * conformance. For drivers which do not have any regulatory
26  * information CRDA provides the complete regulatory solution.
27  * For others it provides a community effort on further restrictions
28  * to enhance compliance.
29  *
30  * Note: When number of rules --> infinity we will not be able to
31  * index on alpha2 any more, instead we'll probably have to
32  * rely on some SHA1 checksum of the regdomain for example.
33  *
34  */
35 #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
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 /* Keep the ordering from large to small */
52 static u32 supported_bandwidths[] = {
53         MHZ_TO_KHZ(40),
54         MHZ_TO_KHZ(20),
55 };
56
57 /* Central wireless core regulatory domains, we only need two,
58  * the current one and a world regulatory domain in case we have no
59  * information to give us an alpha2 */
60 const struct ieee80211_regdomain *cfg80211_regdomain;
61
62 /* We use this as a place for the rd structure built from the
63  * last parsed country IE to rest until CRDA gets back to us with
64  * what it thinks should apply for the same country */
65 static const struct ieee80211_regdomain *country_ie_regdomain;
66
67 /* We keep a static world regulatory domain in case of the absence of CRDA */
68 static const struct ieee80211_regdomain world_regdom = {
69         .n_reg_rules = 1,
70         .alpha2 =  "00",
71         .reg_rules = {
72                 REG_RULE(2412-10, 2462+10, 40, 6, 20,
73                         NL80211_RRF_PASSIVE_SCAN |
74                         NL80211_RRF_NO_IBSS),
75         }
76 };
77
78 static const struct ieee80211_regdomain *cfg80211_world_regdom =
79         &world_regdom;
80
81 #ifdef CONFIG_WIRELESS_OLD_REGULATORY
82 static char *ieee80211_regdom = "US";
83 module_param(ieee80211_regdom, charp, 0444);
84 MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain code");
85
86 /* We assume 40 MHz bandwidth for the old regulatory work.
87  * We make emphasis we are using the exact same frequencies
88  * as before */
89
90 static const struct ieee80211_regdomain us_regdom = {
91         .n_reg_rules = 6,
92         .alpha2 =  "US",
93         .reg_rules = {
94                 /* IEEE 802.11b/g, channels 1..11 */
95                 REG_RULE(2412-10, 2462+10, 40, 6, 27, 0),
96                 /* IEEE 802.11a, channel 36 */
97                 REG_RULE(5180-10, 5180+10, 40, 6, 23, 0),
98                 /* IEEE 802.11a, channel 40 */
99                 REG_RULE(5200-10, 5200+10, 40, 6, 23, 0),
100                 /* IEEE 802.11a, channel 44 */
101                 REG_RULE(5220-10, 5220+10, 40, 6, 23, 0),
102                 /* IEEE 802.11a, channels 48..64 */
103                 REG_RULE(5240-10, 5320+10, 40, 6, 23, 0),
104                 /* IEEE 802.11a, channels 149..165, outdoor */
105                 REG_RULE(5745-10, 5825+10, 40, 6, 30, 0),
106         }
107 };
108
109 static const struct ieee80211_regdomain jp_regdom = {
110         .n_reg_rules = 3,
111         .alpha2 =  "JP",
112         .reg_rules = {
113                 /* IEEE 802.11b/g, channels 1..14 */
114                 REG_RULE(2412-10, 2484+10, 40, 6, 20, 0),
115                 /* IEEE 802.11a, channels 34..48 */
116                 REG_RULE(5170-10, 5240+10, 40, 6, 20,
117                         NL80211_RRF_PASSIVE_SCAN),
118                 /* IEEE 802.11a, channels 52..64 */
119                 REG_RULE(5260-10, 5320+10, 40, 6, 20,
120                         NL80211_RRF_NO_IBSS |
121                         NL80211_RRF_DFS),
122         }
123 };
124
125 static const struct ieee80211_regdomain eu_regdom = {
126         .n_reg_rules = 6,
127         /* This alpha2 is bogus, we leave it here just for stupid
128          * backward compatibility */
129         .alpha2 =  "EU",
130         .reg_rules = {
131                 /* IEEE 802.11b/g, channels 1..13 */
132                 REG_RULE(2412-10, 2472+10, 40, 6, 20, 0),
133                 /* IEEE 802.11a, channel 36 */
134                 REG_RULE(5180-10, 5180+10, 40, 6, 23,
135                         NL80211_RRF_PASSIVE_SCAN),
136                 /* IEEE 802.11a, channel 40 */
137                 REG_RULE(5200-10, 5200+10, 40, 6, 23,
138                         NL80211_RRF_PASSIVE_SCAN),
139                 /* IEEE 802.11a, channel 44 */
140                 REG_RULE(5220-10, 5220+10, 40, 6, 23,
141                         NL80211_RRF_PASSIVE_SCAN),
142                 /* IEEE 802.11a, channels 48..64 */
143                 REG_RULE(5240-10, 5320+10, 40, 6, 20,
144                         NL80211_RRF_NO_IBSS |
145                         NL80211_RRF_DFS),
146                 /* IEEE 802.11a, channels 100..140 */
147                 REG_RULE(5500-10, 5700+10, 40, 6, 30,
148                         NL80211_RRF_NO_IBSS |
149                         NL80211_RRF_DFS),
150         }
151 };
152
153 static const struct ieee80211_regdomain *static_regdom(char *alpha2)
154 {
155         if (alpha2[0] == 'U' && alpha2[1] == 'S')
156                 return &us_regdom;
157         if (alpha2[0] == 'J' && alpha2[1] == 'P')
158                 return &jp_regdom;
159         if (alpha2[0] == 'E' && alpha2[1] == 'U')
160                 return &eu_regdom;
161         /* Default, as per the old rules */
162         return &us_regdom;
163 }
164
165 static bool is_old_static_regdom(const struct ieee80211_regdomain *rd)
166 {
167         if (rd == &us_regdom || rd == &jp_regdom || rd == &eu_regdom)
168                 return true;
169         return false;
170 }
171 #else
172 static inline bool is_old_static_regdom(const struct ieee80211_regdomain *rd)
173 {
174         return false;
175 }
176 #endif
177
178 static void reset_regdomains(void)
179 {
180         /* avoid freeing static information or freeing something twice */
181         if (cfg80211_regdomain == cfg80211_world_regdom)
182                 cfg80211_regdomain = NULL;
183         if (cfg80211_world_regdom == &world_regdom)
184                 cfg80211_world_regdom = NULL;
185         if (cfg80211_regdomain == &world_regdom)
186                 cfg80211_regdomain = NULL;
187         if (is_old_static_regdom(cfg80211_regdomain))
188                 cfg80211_regdomain = NULL;
189
190         kfree(cfg80211_regdomain);
191         kfree(cfg80211_world_regdom);
192
193         cfg80211_world_regdom = &world_regdom;
194         cfg80211_regdomain = NULL;
195 }
196
197 /* Dynamic world regulatory domain requested by the wireless
198  * core upon initialization */
199 static void update_world_regdomain(const struct ieee80211_regdomain *rd)
200 {
201         BUG_ON(!last_request);
202
203         reset_regdomains();
204
205         cfg80211_world_regdom = rd;
206         cfg80211_regdomain = rd;
207 }
208
209 bool is_world_regdom(const char *alpha2)
210 {
211         if (!alpha2)
212                 return false;
213         if (alpha2[0] == '0' && alpha2[1] == '0')
214                 return true;
215         return false;
216 }
217
218 static bool is_alpha2_set(const char *alpha2)
219 {
220         if (!alpha2)
221                 return false;
222         if (alpha2[0] != 0 && alpha2[1] != 0)
223                 return true;
224         return false;
225 }
226
227 static bool is_alpha_upper(char letter)
228 {
229         /* ASCII A - Z */
230         if (letter >= 65 && letter <= 90)
231                 return true;
232         return false;
233 }
234
235 static bool is_unknown_alpha2(const char *alpha2)
236 {
237         if (!alpha2)
238                 return false;
239         /* Special case where regulatory domain was built by driver
240          * but a specific alpha2 cannot be determined */
241         if (alpha2[0] == '9' && alpha2[1] == '9')
242                 return true;
243         return false;
244 }
245
246 static bool is_intersected_alpha2(const char *alpha2)
247 {
248         if (!alpha2)
249                 return false;
250         /* Special case where regulatory domain is the
251          * result of an intersection between two regulatory domain
252          * structures */
253         if (alpha2[0] == '9' && alpha2[1] == '8')
254                 return true;
255         return false;
256 }
257
258 static bool is_an_alpha2(const char *alpha2)
259 {
260         if (!alpha2)
261                 return false;
262         if (is_alpha_upper(alpha2[0]) && is_alpha_upper(alpha2[1]))
263                 return true;
264         return false;
265 }
266
267 static bool alpha2_equal(const char *alpha2_x, const char *alpha2_y)
268 {
269         if (!alpha2_x || !alpha2_y)
270                 return false;
271         if (alpha2_x[0] == alpha2_y[0] &&
272                 alpha2_x[1] == alpha2_y[1])
273                 return true;
274         return false;
275 }
276
277 static bool regdom_changed(const char *alpha2)
278 {
279         if (!cfg80211_regdomain)
280                 return true;
281         if (alpha2_equal(cfg80211_regdomain->alpha2, alpha2))
282                 return false;
283         return true;
284 }
285
286 /**
287  * country_ie_integrity_changes - tells us if the country IE has changed
288  * @checksum: checksum of country IE of fields we are interested in
289  *
290  * If the country IE has not changed you can ignore it safely. This is
291  * useful to determine if two devices are seeing two different country IEs
292  * even on the same alpha2. Note that this will return false if no IE has
293  * been set on the wireless core yet.
294  */
295 static bool country_ie_integrity_changes(u32 checksum)
296 {
297         /* If no IE has been set then the checksum doesn't change */
298         if (unlikely(!last_request->country_ie_checksum))
299                 return false;
300         if (unlikely(last_request->country_ie_checksum != checksum))
301                 return true;
302         return false;
303 }
304
305 /* This lets us keep regulatory code which is updated on a regulatory
306  * basis in userspace. */
307 static int call_crda(const char *alpha2)
308 {
309         char country_env[9 + 2] = "COUNTRY=";
310         char *envp[] = {
311                 country_env,
312                 NULL
313         };
314
315         if (!is_world_regdom((char *) alpha2))
316                 printk(KERN_INFO "cfg80211: Calling CRDA for country: %c%c\n",
317                         alpha2[0], alpha2[1]);
318         else
319                 printk(KERN_INFO "cfg80211: Calling CRDA to update world "
320                         "regulatory domain\n");
321
322         country_env[8] = alpha2[0];
323         country_env[9] = alpha2[1];
324
325         return kobject_uevent_env(&reg_pdev->dev.kobj, KOBJ_CHANGE, envp);
326 }
327
328 /* Used by nl80211 before kmalloc'ing our regulatory domain */
329 bool reg_is_valid_request(const char *alpha2)
330 {
331         if (!last_request)
332                 return false;
333
334         return alpha2_equal(last_request->alpha2, alpha2);
335 }
336
337 /* Sanity check on a regulatory rule */
338 static bool is_valid_reg_rule(const struct ieee80211_reg_rule *rule)
339 {
340         const struct ieee80211_freq_range *freq_range = &rule->freq_range;
341         u32 freq_diff;
342
343         if (freq_range->start_freq_khz <= 0 || freq_range->end_freq_khz <= 0)
344                 return false;
345
346         if (freq_range->start_freq_khz > freq_range->end_freq_khz)
347                 return false;
348
349         freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
350
351         if (freq_diff <= 0 || freq_range->max_bandwidth_khz > freq_diff)
352                 return false;
353
354         return true;
355 }
356
357 static bool is_valid_rd(const struct ieee80211_regdomain *rd)
358 {
359         const struct ieee80211_reg_rule *reg_rule = NULL;
360         unsigned int i;
361
362         if (!rd->n_reg_rules)
363                 return false;
364
365         if (WARN_ON(rd->n_reg_rules > NL80211_MAX_SUPP_REG_RULES))
366                 return false;
367
368         for (i = 0; i < rd->n_reg_rules; i++) {
369                 reg_rule = &rd->reg_rules[i];
370                 if (!is_valid_reg_rule(reg_rule))
371                         return false;
372         }
373
374         return true;
375 }
376
377 /* Returns value in KHz */
378 static u32 freq_max_bandwidth(const struct ieee80211_freq_range *freq_range,
379         u32 freq)
380 {
381         unsigned int i;
382         for (i = 0; i < ARRAY_SIZE(supported_bandwidths); i++) {
383                 u32 start_freq_khz = freq - supported_bandwidths[i]/2;
384                 u32 end_freq_khz = freq + supported_bandwidths[i]/2;
385                 if (start_freq_khz >= freq_range->start_freq_khz &&
386                         end_freq_khz <= freq_range->end_freq_khz)
387                         return supported_bandwidths[i];
388         }
389         return 0;
390 }
391
392 /**
393  * freq_in_rule_band - tells us if a frequency is in a frequency band
394  * @freq_range: frequency rule we want to query
395  * @freq_khz: frequency we are inquiring about
396  *
397  * This lets us know if a specific frequency rule is or is not relevant to
398  * a specific frequency's band. Bands are device specific and artificial
399  * definitions (the "2.4 GHz band" and the "5 GHz band"), however it is
400  * safe for now to assume that a frequency rule should not be part of a
401  * frequency's band if the start freq or end freq are off by more than 2 GHz.
402  * This resolution can be lowered and should be considered as we add
403  * regulatory rule support for other "bands".
404  **/
405 static bool freq_in_rule_band(const struct ieee80211_freq_range *freq_range,
406         u32 freq_khz)
407 {
408 #define ONE_GHZ_IN_KHZ  1000000
409         if (abs(freq_khz - freq_range->start_freq_khz) <= (2 * ONE_GHZ_IN_KHZ))
410                 return true;
411         if (abs(freq_khz - freq_range->end_freq_khz) <= (2 * ONE_GHZ_IN_KHZ))
412                 return true;
413         return false;
414 #undef ONE_GHZ_IN_KHZ
415 }
416
417 /* Converts a country IE to a regulatory domain. A regulatory domain
418  * structure has a lot of information which the IE doesn't yet have,
419  * so for the other values we use upper max values as we will intersect
420  * with our userspace regulatory agent to get lower bounds. */
421 static struct ieee80211_regdomain *country_ie_2_rd(
422                                 u8 *country_ie,
423                                 u8 country_ie_len,
424                                 u32 *checksum)
425 {
426         struct ieee80211_regdomain *rd = NULL;
427         unsigned int i = 0;
428         char alpha2[2];
429         u32 flags = 0;
430         u32 num_rules = 0, size_of_regd = 0;
431         u8 *triplets_start = NULL;
432         u8 len_at_triplet = 0;
433         /* the last channel we have registered in a subband (triplet) */
434         int last_sub_max_channel = 0;
435
436         *checksum = 0xDEADBEEF;
437
438         /* Country IE requirements */
439         BUG_ON(country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN ||
440                 country_ie_len & 0x01);
441
442         alpha2[0] = country_ie[0];
443         alpha2[1] = country_ie[1];
444
445         /*
446          * Third octet can be:
447          *    'I' - Indoor
448          *    'O' - Outdoor
449          *
450          *  anything else we assume is no restrictions
451          */
452         if (country_ie[2] == 'I')
453                 flags = NL80211_RRF_NO_OUTDOOR;
454         else if (country_ie[2] == 'O')
455                 flags = NL80211_RRF_NO_INDOOR;
456
457         country_ie += 3;
458         country_ie_len -= 3;
459
460         triplets_start = country_ie;
461         len_at_triplet = country_ie_len;
462
463         *checksum ^= ((flags ^ alpha2[0] ^ alpha2[1]) << 8);
464
465         /* We need to build a reg rule for each triplet, but first we must
466          * calculate the number of reg rules we will need. We will need one
467          * for each channel subband */
468         while (country_ie_len >= 3) {
469                 int end_channel = 0;
470                 struct ieee80211_country_ie_triplet *triplet =
471                         (struct ieee80211_country_ie_triplet *) country_ie;
472                 int cur_sub_max_channel = 0, cur_channel = 0;
473
474                 if (triplet->ext.reg_extension_id >=
475                                 IEEE80211_COUNTRY_EXTENSION_ID) {
476                         country_ie += 3;
477                         country_ie_len -= 3;
478                         continue;
479                 }
480
481                 /* 2 GHz */
482                 if (triplet->chans.first_channel <= 14)
483                         end_channel = triplet->chans.first_channel +
484                                 triplet->chans.num_channels;
485                 else
486                         /*
487                          * 5 GHz -- For example in country IEs if the first
488                          * channel given is 36 and the number of channels is 4
489                          * then the individual channel numbers defined for the
490                          * 5 GHz PHY by these parameters are: 36, 40, 44, and 48
491                          * and not 36, 37, 38, 39.
492                          *
493                          * See: http://tinyurl.com/11d-clarification
494                          */
495                         end_channel =  triplet->chans.first_channel +
496                                 (4 * (triplet->chans.num_channels - 1));
497
498                 cur_channel = triplet->chans.first_channel;
499                 cur_sub_max_channel = end_channel;
500
501                 /* Basic sanity check */
502                 if (cur_sub_max_channel < cur_channel)
503                         return NULL;
504
505                 /* Do not allow overlapping channels. Also channels
506                  * passed in each subband must be monotonically
507                  * increasing */
508                 if (last_sub_max_channel) {
509                         if (cur_channel <= last_sub_max_channel)
510                                 return NULL;
511                         if (cur_sub_max_channel <= last_sub_max_channel)
512                                 return NULL;
513                 }
514
515                 /* When dot11RegulatoryClassesRequired is supported
516                  * we can throw ext triplets as part of this soup,
517                  * for now we don't care when those change as we
518                  * don't support them */
519                 *checksum ^= ((cur_channel ^ cur_sub_max_channel) << 8) |
520                   ((cur_sub_max_channel ^ cur_sub_max_channel) << 16) |
521                   ((triplet->chans.max_power ^ cur_sub_max_channel) << 24);
522
523                 last_sub_max_channel = cur_sub_max_channel;
524
525                 country_ie += 3;
526                 country_ie_len -= 3;
527                 num_rules++;
528
529                 /* Note: this is not a IEEE requirement but
530                  * simply a memory requirement */
531                 if (num_rules > NL80211_MAX_SUPP_REG_RULES)
532                         return NULL;
533         }
534
535         country_ie = triplets_start;
536         country_ie_len = len_at_triplet;
537
538         size_of_regd = sizeof(struct ieee80211_regdomain) +
539                 (num_rules * sizeof(struct ieee80211_reg_rule));
540
541         rd = kzalloc(size_of_regd, GFP_KERNEL);
542         if (!rd)
543                 return NULL;
544
545         rd->n_reg_rules = num_rules;
546         rd->alpha2[0] = alpha2[0];
547         rd->alpha2[1] = alpha2[1];
548
549         /* This time around we fill in the rd */
550         while (country_ie_len >= 3) {
551                 int end_channel = 0;
552                 struct ieee80211_country_ie_triplet *triplet =
553                         (struct ieee80211_country_ie_triplet *) country_ie;
554                 struct ieee80211_reg_rule *reg_rule = NULL;
555                 struct ieee80211_freq_range *freq_range = NULL;
556                 struct ieee80211_power_rule *power_rule = NULL;
557
558                 /* Must parse if dot11RegulatoryClassesRequired is true,
559                  * we don't support this yet */
560                 if (triplet->ext.reg_extension_id >=
561                                 IEEE80211_COUNTRY_EXTENSION_ID) {
562                         country_ie += 3;
563                         country_ie_len -= 3;
564                         continue;
565                 }
566
567                 reg_rule = &rd->reg_rules[i];
568                 freq_range = &reg_rule->freq_range;
569                 power_rule = &reg_rule->power_rule;
570
571                 reg_rule->flags = flags;
572
573                 /* 2 GHz */
574                 if (triplet->chans.first_channel <= 14)
575                         end_channel = triplet->chans.first_channel +
576                                 triplet->chans.num_channels;
577                 else
578                         end_channel =  triplet->chans.first_channel +
579                                 (4 * (triplet->chans.num_channels - 1));
580
581                 /* The +10 is since the regulatory domain expects
582                  * the actual band edge, not the center of freq for
583                  * its start and end freqs, assuming 20 MHz bandwidth on
584                  * the channels passed */
585                 freq_range->start_freq_khz =
586                         MHZ_TO_KHZ(ieee80211_channel_to_frequency(
587                                 triplet->chans.first_channel) - 10);
588                 freq_range->end_freq_khz =
589                         MHZ_TO_KHZ(ieee80211_channel_to_frequency(
590                                 end_channel) + 10);
591
592                 /* Large arbitrary values, we intersect later */
593                 /* Increment this if we ever support >= 40 MHz channels
594                  * in IEEE 802.11 */
595                 freq_range->max_bandwidth_khz = MHZ_TO_KHZ(40);
596                 power_rule->max_antenna_gain = DBI_TO_MBI(100);
597                 power_rule->max_eirp = DBM_TO_MBM(100);
598
599                 country_ie += 3;
600                 country_ie_len -= 3;
601                 i++;
602
603                 BUG_ON(i > NL80211_MAX_SUPP_REG_RULES);
604         }
605
606         return rd;
607 }
608
609
610 /* Helper for regdom_intersect(), this does the real
611  * mathematical intersection fun */
612 static int reg_rules_intersect(
613         const struct ieee80211_reg_rule *rule1,
614         const struct ieee80211_reg_rule *rule2,
615         struct ieee80211_reg_rule *intersected_rule)
616 {
617         const struct ieee80211_freq_range *freq_range1, *freq_range2;
618         struct ieee80211_freq_range *freq_range;
619         const struct ieee80211_power_rule *power_rule1, *power_rule2;
620         struct ieee80211_power_rule *power_rule;
621         u32 freq_diff;
622
623         freq_range1 = &rule1->freq_range;
624         freq_range2 = &rule2->freq_range;
625         freq_range = &intersected_rule->freq_range;
626
627         power_rule1 = &rule1->power_rule;
628         power_rule2 = &rule2->power_rule;
629         power_rule = &intersected_rule->power_rule;
630
631         freq_range->start_freq_khz = max(freq_range1->start_freq_khz,
632                 freq_range2->start_freq_khz);
633         freq_range->end_freq_khz = min(freq_range1->end_freq_khz,
634                 freq_range2->end_freq_khz);
635         freq_range->max_bandwidth_khz = min(freq_range1->max_bandwidth_khz,
636                 freq_range2->max_bandwidth_khz);
637
638         freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
639         if (freq_range->max_bandwidth_khz > freq_diff)
640                 freq_range->max_bandwidth_khz = freq_diff;
641
642         power_rule->max_eirp = min(power_rule1->max_eirp,
643                 power_rule2->max_eirp);
644         power_rule->max_antenna_gain = min(power_rule1->max_antenna_gain,
645                 power_rule2->max_antenna_gain);
646
647         intersected_rule->flags = (rule1->flags | rule2->flags);
648
649         if (!is_valid_reg_rule(intersected_rule))
650                 return -EINVAL;
651
652         return 0;
653 }
654
655 /**
656  * regdom_intersect - do the intersection between two regulatory domains
657  * @rd1: first regulatory domain
658  * @rd2: second regulatory domain
659  *
660  * Use this function to get the intersection between two regulatory domains.
661  * Once completed we will mark the alpha2 for the rd as intersected, "98",
662  * as no one single alpha2 can represent this regulatory domain.
663  *
664  * Returns a pointer to the regulatory domain structure which will hold the
665  * resulting intersection of rules between rd1 and rd2. We will
666  * kzalloc() this structure for you.
667  */
668 static struct ieee80211_regdomain *regdom_intersect(
669         const struct ieee80211_regdomain *rd1,
670         const struct ieee80211_regdomain *rd2)
671 {
672         int r, size_of_regd;
673         unsigned int x, y;
674         unsigned int num_rules = 0, rule_idx = 0;
675         const struct ieee80211_reg_rule *rule1, *rule2;
676         struct ieee80211_reg_rule *intersected_rule;
677         struct ieee80211_regdomain *rd;
678         /* This is just a dummy holder to help us count */
679         struct ieee80211_reg_rule irule;
680
681         /* Uses the stack temporarily for counter arithmetic */
682         intersected_rule = &irule;
683
684         memset(intersected_rule, 0, sizeof(struct ieee80211_reg_rule));
685
686         if (!rd1 || !rd2)
687                 return NULL;
688
689         /* First we get a count of the rules we'll need, then we actually
690          * build them. This is to so we can malloc() and free() a
691          * regdomain once. The reason we use reg_rules_intersect() here
692          * is it will return -EINVAL if the rule computed makes no sense.
693          * All rules that do check out OK are valid. */
694
695         for (x = 0; x < rd1->n_reg_rules; x++) {
696                 rule1 = &rd1->reg_rules[x];
697                 for (y = 0; y < rd2->n_reg_rules; y++) {
698                         rule2 = &rd2->reg_rules[y];
699                         if (!reg_rules_intersect(rule1, rule2,
700                                         intersected_rule))
701                                 num_rules++;
702                         memset(intersected_rule, 0,
703                                         sizeof(struct ieee80211_reg_rule));
704                 }
705         }
706
707         if (!num_rules)
708                 return NULL;
709
710         size_of_regd = sizeof(struct ieee80211_regdomain) +
711                 ((num_rules + 1) * sizeof(struct ieee80211_reg_rule));
712
713         rd = kzalloc(size_of_regd, GFP_KERNEL);
714         if (!rd)
715                 return NULL;
716
717         for (x = 0; x < rd1->n_reg_rules; x++) {
718                 rule1 = &rd1->reg_rules[x];
719                 for (y = 0; y < rd2->n_reg_rules; y++) {
720                         rule2 = &rd2->reg_rules[y];
721                         /* This time around instead of using the stack lets
722                          * write to the target rule directly saving ourselves
723                          * a memcpy() */
724                         intersected_rule = &rd->reg_rules[rule_idx];
725                         r = reg_rules_intersect(rule1, rule2,
726                                 intersected_rule);
727                         /* No need to memset here the intersected rule here as
728                          * we're not using the stack anymore */
729                         if (r)
730                                 continue;
731                         rule_idx++;
732                 }
733         }
734
735         if (rule_idx != num_rules) {
736                 kfree(rd);
737                 return NULL;
738         }
739
740         rd->n_reg_rules = num_rules;
741         rd->alpha2[0] = '9';
742         rd->alpha2[1] = '8';
743
744         return rd;
745 }
746
747 /* XXX: add support for the rest of enum nl80211_reg_rule_flags, we may
748  * want to just have the channel structure use these */
749 static u32 map_regdom_flags(u32 rd_flags)
750 {
751         u32 channel_flags = 0;
752         if (rd_flags & NL80211_RRF_PASSIVE_SCAN)
753                 channel_flags |= IEEE80211_CHAN_PASSIVE_SCAN;
754         if (rd_flags & NL80211_RRF_NO_IBSS)
755                 channel_flags |= IEEE80211_CHAN_NO_IBSS;
756         if (rd_flags & NL80211_RRF_DFS)
757                 channel_flags |= IEEE80211_CHAN_RADAR;
758         return channel_flags;
759 }
760
761 static int freq_reg_info_regd(struct wiphy *wiphy,
762                               u32 center_freq,
763                               u32 *bandwidth,
764                               const struct ieee80211_reg_rule **reg_rule,
765                               const struct ieee80211_regdomain *custom_regd)
766 {
767         int i;
768         bool band_rule_found = false;
769         const struct ieee80211_regdomain *regd;
770         u32 max_bandwidth = 0;
771
772         regd = custom_regd ? custom_regd : cfg80211_regdomain;
773
774         /* Follow the driver's regulatory domain, if present, unless a country
775          * IE has been processed or a user wants to help complaince further */
776         if (last_request->initiator != REGDOM_SET_BY_COUNTRY_IE &&
777             last_request->initiator != REGDOM_SET_BY_USER &&
778             wiphy->regd)
779                 regd = wiphy->regd;
780
781         if (!regd)
782                 return -EINVAL;
783
784         for (i = 0; i < regd->n_reg_rules; i++) {
785                 const struct ieee80211_reg_rule *rr;
786                 const struct ieee80211_freq_range *fr = NULL;
787                 const struct ieee80211_power_rule *pr = NULL;
788
789                 rr = &regd->reg_rules[i];
790                 fr = &rr->freq_range;
791                 pr = &rr->power_rule;
792
793                 /* We only need to know if one frequency rule was
794                  * was in center_freq's band, that's enough, so lets
795                  * not overwrite it once found */
796                 if (!band_rule_found)
797                         band_rule_found = freq_in_rule_band(fr, center_freq);
798
799                 max_bandwidth = freq_max_bandwidth(fr, center_freq);
800
801                 if (max_bandwidth && *bandwidth <= max_bandwidth) {
802                         *reg_rule = rr;
803                         *bandwidth = max_bandwidth;
804                         break;
805                 }
806         }
807
808         if (!band_rule_found)
809                 return -ERANGE;
810
811         return !max_bandwidth;
812 }
813 EXPORT_SYMBOL(freq_reg_info);
814
815 int freq_reg_info(struct wiphy *wiphy, u32 center_freq, u32 *bandwidth,
816                          const struct ieee80211_reg_rule **reg_rule)
817 {
818         return freq_reg_info_regd(wiphy, center_freq,
819                 bandwidth, reg_rule, NULL);
820 }
821
822 static void handle_channel(struct wiphy *wiphy, enum ieee80211_band band,
823                            unsigned int chan_idx)
824 {
825         int r;
826         u32 flags;
827         u32 max_bandwidth = 0;
828         const struct ieee80211_reg_rule *reg_rule = NULL;
829         const struct ieee80211_power_rule *power_rule = NULL;
830         struct ieee80211_supported_band *sband;
831         struct ieee80211_channel *chan;
832
833         sband = wiphy->bands[band];
834         BUG_ON(chan_idx >= sband->n_channels);
835         chan = &sband->channels[chan_idx];
836
837         flags = chan->orig_flags;
838
839         r = freq_reg_info(wiphy, MHZ_TO_KHZ(chan->center_freq),
840                 &max_bandwidth, &reg_rule);
841
842         if (r) {
843                 /* This means no regulatory rule was found in the country IE
844                  * with a frequency range on the center_freq's band, since
845                  * IEEE-802.11 allows for a country IE to have a subset of the
846                  * regulatory information provided in a country we ignore
847                  * disabling the channel unless at least one reg rule was
848                  * found on the center_freq's band. For details see this
849                  * clarification:
850                  *
851                  * http://tinyurl.com/11d-clarification
852                  */
853                 if (r == -ERANGE &&
854                     last_request->initiator == REGDOM_SET_BY_COUNTRY_IE) {
855 #ifdef CONFIG_CFG80211_REG_DEBUG
856                         printk(KERN_DEBUG "cfg80211: Leaving channel %d MHz "
857                                 "intact on %s - no rule found in band on "
858                                 "Country IE\n",
859                                 chan->center_freq, wiphy_name(wiphy));
860 #endif
861                 } else {
862                 /* In this case we know the country IE has at least one reg rule
863                  * for the band so we respect its band definitions */
864 #ifdef CONFIG_CFG80211_REG_DEBUG
865                         if (last_request->initiator == REGDOM_SET_BY_COUNTRY_IE)
866                                 printk(KERN_DEBUG "cfg80211: Disabling "
867                                         "channel %d MHz on %s due to "
868                                         "Country IE\n",
869                                         chan->center_freq, wiphy_name(wiphy));
870 #endif
871                         flags |= IEEE80211_CHAN_DISABLED;
872                         chan->flags = flags;
873                 }
874                 return;
875         }
876
877         power_rule = &reg_rule->power_rule;
878
879         if (last_request->initiator == REGDOM_SET_BY_DRIVER &&
880             last_request->wiphy && last_request->wiphy == wiphy &&
881             last_request->wiphy->strict_regulatory) {
882                 /* This gaurantees the driver's requested regulatory domain
883                  * will always be used as a base for further regulatory
884                  * settings */
885                 chan->flags = chan->orig_flags =
886                         map_regdom_flags(reg_rule->flags);
887                 chan->max_antenna_gain = chan->orig_mag =
888                         (int) MBI_TO_DBI(power_rule->max_antenna_gain);
889                 chan->max_bandwidth = KHZ_TO_MHZ(max_bandwidth);
890                 chan->max_power = chan->orig_mpwr =
891                         (int) MBM_TO_DBM(power_rule->max_eirp);
892                 return;
893         }
894
895         chan->flags = flags | map_regdom_flags(reg_rule->flags);
896         chan->max_antenna_gain = min(chan->orig_mag,
897                 (int) MBI_TO_DBI(power_rule->max_antenna_gain));
898         chan->max_bandwidth = KHZ_TO_MHZ(max_bandwidth);
899         if (chan->orig_mpwr)
900                 chan->max_power = min(chan->orig_mpwr,
901                         (int) MBM_TO_DBM(power_rule->max_eirp));
902         else
903                 chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
904 }
905
906 static void handle_band(struct wiphy *wiphy, enum ieee80211_band band)
907 {
908         unsigned int i;
909         struct ieee80211_supported_band *sband;
910
911         BUG_ON(!wiphy->bands[band]);
912         sband = wiphy->bands[band];
913
914         for (i = 0; i < sband->n_channels; i++)
915                 handle_channel(wiphy, band, i);
916 }
917
918 static bool ignore_reg_update(struct wiphy *wiphy, enum reg_set_by setby)
919 {
920         if (!last_request)
921                 return true;
922         if (setby == REGDOM_SET_BY_CORE &&
923                   wiphy->custom_regulatory)
924                 return true;
925         /* wiphy->regd will be set once the device has its own
926          * desired regulatory domain set */
927         if (wiphy->strict_regulatory && !wiphy->regd &&
928             !is_world_regdom(last_request->alpha2))
929                 return true;
930         return false;
931 }
932
933 static void update_all_wiphy_regulatory(enum reg_set_by setby)
934 {
935         struct cfg80211_registered_device *drv;
936
937         list_for_each_entry(drv, &cfg80211_drv_list, list)
938                 wiphy_update_regulatory(&drv->wiphy, setby);
939 }
940
941 void wiphy_update_regulatory(struct wiphy *wiphy, enum reg_set_by setby)
942 {
943         enum ieee80211_band band;
944
945         if (ignore_reg_update(wiphy, setby))
946                 return;
947         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
948                 if (wiphy->bands[band])
949                         handle_band(wiphy, band);
950         }
951         if (wiphy->reg_notifier)
952                 wiphy->reg_notifier(wiphy, last_request);
953 }
954
955 static void handle_channel_custom(struct wiphy *wiphy,
956                                   enum ieee80211_band band,
957                                   unsigned int chan_idx,
958                                   const struct ieee80211_regdomain *regd)
959 {
960         int r;
961         u32 max_bandwidth = 0;
962         const struct ieee80211_reg_rule *reg_rule = NULL;
963         const struct ieee80211_power_rule *power_rule = NULL;
964         struct ieee80211_supported_band *sband;
965         struct ieee80211_channel *chan;
966
967         sband = wiphy->bands[band];
968         BUG_ON(chan_idx >= sband->n_channels);
969         chan = &sband->channels[chan_idx];
970
971         r = freq_reg_info_regd(wiphy, MHZ_TO_KHZ(chan->center_freq),
972                 &max_bandwidth, &reg_rule, regd);
973
974         if (r) {
975                 chan->flags = IEEE80211_CHAN_DISABLED;
976                 return;
977         }
978
979         power_rule = &reg_rule->power_rule;
980
981         chan->flags |= map_regdom_flags(reg_rule->flags);
982         chan->max_antenna_gain = (int) MBI_TO_DBI(power_rule->max_antenna_gain);
983         chan->max_bandwidth = KHZ_TO_MHZ(max_bandwidth);
984         chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
985 }
986
987 static void handle_band_custom(struct wiphy *wiphy, enum ieee80211_band band,
988                                const struct ieee80211_regdomain *regd)
989 {
990         unsigned int i;
991         struct ieee80211_supported_band *sband;
992
993         BUG_ON(!wiphy->bands[band]);
994         sband = wiphy->bands[band];
995
996         for (i = 0; i < sband->n_channels; i++)
997                 handle_channel_custom(wiphy, band, i, regd);
998 }
999
1000 /* Used by drivers prior to wiphy registration */
1001 void wiphy_apply_custom_regulatory(struct wiphy *wiphy,
1002                                    const struct ieee80211_regdomain *regd)
1003 {
1004         enum ieee80211_band band;
1005         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1006                 if (wiphy->bands[band])
1007                         handle_band_custom(wiphy, band, regd);
1008         }
1009 }
1010 EXPORT_SYMBOL(wiphy_apply_custom_regulatory);
1011
1012 static int reg_copy_regd(const struct ieee80211_regdomain **dst_regd,
1013                          const struct ieee80211_regdomain *src_regd)
1014 {
1015         struct ieee80211_regdomain *regd;
1016         int size_of_regd = 0;
1017         unsigned int i;
1018
1019         size_of_regd = sizeof(struct ieee80211_regdomain) +
1020           ((src_regd->n_reg_rules + 1) * sizeof(struct ieee80211_reg_rule));
1021
1022         regd = kzalloc(size_of_regd, GFP_KERNEL);
1023         if (!regd)
1024                 return -ENOMEM;
1025
1026         memcpy(regd, src_regd, sizeof(struct ieee80211_regdomain));
1027
1028         for (i = 0; i < src_regd->n_reg_rules; i++)
1029                 memcpy(&regd->reg_rules[i], &src_regd->reg_rules[i],
1030                         sizeof(struct ieee80211_reg_rule));
1031
1032         *dst_regd = regd;
1033         return 0;
1034 }
1035
1036 /* Return value which can be used by ignore_request() to indicate
1037  * it has been determined we should intersect two regulatory domains */
1038 #define REG_INTERSECT   1
1039
1040 /* This has the logic which determines when a new request
1041  * should be ignored. */
1042 static int ignore_request(struct wiphy *wiphy, enum reg_set_by set_by,
1043                           const char *alpha2)
1044 {
1045         /* All initial requests are respected */
1046         if (!last_request)
1047                 return 0;
1048
1049         switch (set_by) {
1050         case REGDOM_SET_BY_INIT:
1051                 return -EINVAL;
1052         case REGDOM_SET_BY_CORE:
1053                 return -EINVAL;
1054         case REGDOM_SET_BY_COUNTRY_IE:
1055                 if (unlikely(!is_an_alpha2(alpha2)))
1056                         return -EINVAL;
1057                 if (last_request->initiator == REGDOM_SET_BY_COUNTRY_IE) {
1058                         if (last_request->wiphy != wiphy) {
1059                                 /*
1060                                  * Two cards with two APs claiming different
1061                                  * different Country IE alpha2s. We could
1062                                  * intersect them, but that seems unlikely
1063                                  * to be correct. Reject second one for now.
1064                                  */
1065                                 if (!alpha2_equal(alpha2,
1066                                                   cfg80211_regdomain->alpha2))
1067                                         return -EOPNOTSUPP;
1068                                 return -EALREADY;
1069                         }
1070                         /* Two consecutive Country IE hints on the same wiphy.
1071                          * This should be picked up early by the driver/stack */
1072                         if (WARN_ON(!alpha2_equal(cfg80211_regdomain->alpha2,
1073                                   alpha2)))
1074                                 return 0;
1075                         return -EALREADY;
1076                 }
1077                 return REG_INTERSECT;
1078         case REGDOM_SET_BY_DRIVER:
1079                 if (last_request->initiator == REGDOM_SET_BY_CORE) {
1080                         if (is_old_static_regdom(cfg80211_regdomain))
1081                                 return 0;
1082                         if (!alpha2_equal(cfg80211_regdomain->alpha2, alpha2))
1083                                 return 0;
1084                         return -EALREADY;
1085                 }
1086                 return REG_INTERSECT;
1087         case REGDOM_SET_BY_USER:
1088                 if (last_request->initiator == REGDOM_SET_BY_COUNTRY_IE)
1089                         return REG_INTERSECT;
1090                 /* If the user knows better the user should set the regdom
1091                  * to their country before the IE is picked up */
1092                 if (last_request->initiator == REGDOM_SET_BY_USER &&
1093                           last_request->intersect)
1094                         return -EOPNOTSUPP;
1095                 /* Process user requests only after previous user/driver/core
1096                  * requests have been processed */
1097                 if (last_request->initiator == REGDOM_SET_BY_CORE ||
1098                     last_request->initiator == REGDOM_SET_BY_DRIVER ||
1099                     last_request->initiator == REGDOM_SET_BY_USER) {
1100                         if (!alpha2_equal(last_request->alpha2,
1101                             cfg80211_regdomain->alpha2))
1102                                 return -EAGAIN;
1103                 }
1104
1105                 if (!is_old_static_regdom(cfg80211_regdomain) &&
1106                     alpha2_equal(cfg80211_regdomain->alpha2, alpha2))
1107                         return -EALREADY;
1108
1109                 return 0;
1110         }
1111
1112         return -EINVAL;
1113 }
1114
1115 /* Caller must hold &cfg80211_mutex */
1116 int __regulatory_hint(struct wiphy *wiphy, enum reg_set_by set_by,
1117                         const char *alpha2,
1118                         u32 country_ie_checksum,
1119                         enum environment_cap env)
1120 {
1121         struct regulatory_request *request;
1122         bool intersect = false;
1123         int r = 0;
1124
1125         r = ignore_request(wiphy, set_by, alpha2);
1126
1127         if (r == REG_INTERSECT) {
1128                 if (set_by == REGDOM_SET_BY_DRIVER) {
1129                         r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1130                         if (r)
1131                                 return r;
1132                 }
1133                 intersect = true;
1134         } else if (r) {
1135                 /* If the regulatory domain being requested by the
1136                  * driver has already been set just copy it to the
1137                  * wiphy */
1138                 if (r == -EALREADY && set_by == REGDOM_SET_BY_DRIVER) {
1139                         r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1140                         if (r)
1141                                 return r;
1142                         r = -EALREADY;
1143                         goto new_request;
1144                 }
1145                 return r;
1146         }
1147
1148 new_request:
1149         request = kzalloc(sizeof(struct regulatory_request),
1150                           GFP_KERNEL);
1151         if (!request)
1152                 return -ENOMEM;
1153
1154         request->alpha2[0] = alpha2[0];
1155         request->alpha2[1] = alpha2[1];
1156         request->initiator = set_by;
1157         request->wiphy = wiphy;
1158         request->intersect = intersect;
1159         request->country_ie_checksum = country_ie_checksum;
1160         request->country_ie_env = env;
1161
1162         kfree(last_request);
1163         last_request = request;
1164
1165         /* When r == REG_INTERSECT we do need to call CRDA */
1166         if (r < 0)
1167                 return r;
1168
1169         /*
1170          * Note: When CONFIG_WIRELESS_OLD_REGULATORY is enabled
1171          * AND if CRDA is NOT present nothing will happen, if someone
1172          * wants to bother with 11d with OLD_REG you can add a timer.
1173          * If after x amount of time nothing happens you can call:
1174          *
1175          * return set_regdom(country_ie_regdomain);
1176          *
1177          * to intersect with the static rd
1178          */
1179         return call_crda(alpha2);
1180 }
1181
1182 static int regulatory_hint_core(const char *alpha2)
1183 {
1184         struct regulatory_request *request;
1185
1186         BUG_ON(last_request);
1187
1188         request = kzalloc(sizeof(struct regulatory_request),
1189                           GFP_KERNEL);
1190         if (!request)
1191                 return -ENOMEM;
1192
1193         request->alpha2[0] = alpha2[0];
1194         request->alpha2[1] = alpha2[1];
1195         request->initiator = REGDOM_SET_BY_CORE;
1196
1197         last_request = request;
1198
1199         return call_crda(alpha2);
1200 }
1201
1202 void regulatory_hint(struct wiphy *wiphy, const char *alpha2)
1203 {
1204         int r;
1205         BUG_ON(!alpha2);
1206
1207         mutex_lock(&cfg80211_mutex);
1208         r = __regulatory_hint(wiphy, REGDOM_SET_BY_DRIVER,
1209                 alpha2, 0, ENVIRON_ANY);
1210         /* This is required so that the orig_* parameters are saved */
1211         if (r == -EALREADY && wiphy->strict_regulatory)
1212                 wiphy_update_regulatory(wiphy, REGDOM_SET_BY_DRIVER);
1213         mutex_unlock(&cfg80211_mutex);
1214 }
1215 EXPORT_SYMBOL(regulatory_hint);
1216
1217 static bool reg_same_country_ie_hint(struct wiphy *wiphy,
1218                         u32 country_ie_checksum)
1219 {
1220         if (!last_request->wiphy)
1221                 return false;
1222         if (likely(last_request->wiphy != wiphy))
1223                 return !country_ie_integrity_changes(country_ie_checksum);
1224         /* We should not have let these through at this point, they
1225          * should have been picked up earlier by the first alpha2 check
1226          * on the device */
1227         if (WARN_ON(!country_ie_integrity_changes(country_ie_checksum)))
1228                 return true;
1229         return false;
1230 }
1231
1232 void regulatory_hint_11d(struct wiphy *wiphy,
1233                         u8 *country_ie,
1234                         u8 country_ie_len)
1235 {
1236         struct ieee80211_regdomain *rd = NULL;
1237         char alpha2[2];
1238         u32 checksum = 0;
1239         enum environment_cap env = ENVIRON_ANY;
1240
1241         if (!last_request)
1242                 return;
1243
1244         mutex_lock(&cfg80211_mutex);
1245
1246         /* IE len must be evenly divisible by 2 */
1247         if (country_ie_len & 0x01)
1248                 goto out;
1249
1250         if (country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN)
1251                 goto out;
1252
1253         /* Pending country IE processing, this can happen after we
1254          * call CRDA and wait for a response if a beacon was received before
1255          * we were able to process the last regulatory_hint_11d() call */
1256         if (country_ie_regdomain)
1257                 goto out;
1258
1259         alpha2[0] = country_ie[0];
1260         alpha2[1] = country_ie[1];
1261
1262         if (country_ie[2] == 'I')
1263                 env = ENVIRON_INDOOR;
1264         else if (country_ie[2] == 'O')
1265                 env = ENVIRON_OUTDOOR;
1266
1267         /* We will run this for *every* beacon processed for the BSSID, so
1268          * we optimize an early check to exit out early if we don't have to
1269          * do anything */
1270         if (likely(last_request->wiphy)) {
1271                 struct cfg80211_registered_device *drv_last_ie;
1272
1273                 drv_last_ie = wiphy_to_dev(last_request->wiphy);
1274
1275                 /* Lets keep this simple -- we trust the first AP
1276                  * after we intersect with CRDA */
1277                 if (likely(last_request->wiphy == wiphy)) {
1278                         /* Ignore IEs coming in on this wiphy with
1279                          * the same alpha2 and environment cap */
1280                         if (likely(alpha2_equal(drv_last_ie->country_ie_alpha2,
1281                                   alpha2) &&
1282                                   env == drv_last_ie->env)) {
1283                                 goto out;
1284                         }
1285                         /* the wiphy moved on to another BSSID or the AP
1286                          * was reconfigured. XXX: We need to deal with the
1287                          * case where the user suspends and goes to goes
1288                          * to another country, and then gets IEs from an
1289                          * AP with different settings */
1290                         goto out;
1291                 } else {
1292                         /* Ignore IEs coming in on two separate wiphys with
1293                          * the same alpha2 and environment cap */
1294                         if (likely(alpha2_equal(drv_last_ie->country_ie_alpha2,
1295                                   alpha2) &&
1296                                   env == drv_last_ie->env)) {
1297                                 goto out;
1298                         }
1299                         /* We could potentially intersect though */
1300                         goto out;
1301                 }
1302         }
1303
1304         rd = country_ie_2_rd(country_ie, country_ie_len, &checksum);
1305         if (!rd)
1306                 goto out;
1307
1308         /* This will not happen right now but we leave it here for the
1309          * the future when we want to add suspend/resume support and having
1310          * the user move to another country after doing so, or having the user
1311          * move to another AP. Right now we just trust the first AP. This is why
1312          * this is marked as likley(). If we hit this before we add this support
1313          * we want to be informed of it as it would indicate a mistake in the
1314          * current design  */
1315         if (likely(WARN_ON(reg_same_country_ie_hint(wiphy, checksum))))
1316                 goto out;
1317
1318         /* We keep this around for when CRDA comes back with a response so
1319          * we can intersect with that */
1320         country_ie_regdomain = rd;
1321
1322         __regulatory_hint(wiphy, REGDOM_SET_BY_COUNTRY_IE,
1323                 country_ie_regdomain->alpha2, checksum, env);
1324
1325 out:
1326         mutex_unlock(&cfg80211_mutex);
1327 }
1328 EXPORT_SYMBOL(regulatory_hint_11d);
1329
1330 static void print_rd_rules(const struct ieee80211_regdomain *rd)
1331 {
1332         unsigned int i;
1333         const struct ieee80211_reg_rule *reg_rule = NULL;
1334         const struct ieee80211_freq_range *freq_range = NULL;
1335         const struct ieee80211_power_rule *power_rule = NULL;
1336
1337         printk(KERN_INFO "\t(start_freq - end_freq @ bandwidth), "
1338                 "(max_antenna_gain, max_eirp)\n");
1339
1340         for (i = 0; i < rd->n_reg_rules; i++) {
1341                 reg_rule = &rd->reg_rules[i];
1342                 freq_range = &reg_rule->freq_range;
1343                 power_rule = &reg_rule->power_rule;
1344
1345                 /* There may not be documentation for max antenna gain
1346                  * in certain regions */
1347                 if (power_rule->max_antenna_gain)
1348                         printk(KERN_INFO "\t(%d KHz - %d KHz @ %d KHz), "
1349                                 "(%d mBi, %d mBm)\n",
1350                                 freq_range->start_freq_khz,
1351                                 freq_range->end_freq_khz,
1352                                 freq_range->max_bandwidth_khz,
1353                                 power_rule->max_antenna_gain,
1354                                 power_rule->max_eirp);
1355                 else
1356                         printk(KERN_INFO "\t(%d KHz - %d KHz @ %d KHz), "
1357                                 "(N/A, %d mBm)\n",
1358                                 freq_range->start_freq_khz,
1359                                 freq_range->end_freq_khz,
1360                                 freq_range->max_bandwidth_khz,
1361                                 power_rule->max_eirp);
1362         }
1363 }
1364
1365 static void print_regdomain(const struct ieee80211_regdomain *rd)
1366 {
1367
1368         if (is_intersected_alpha2(rd->alpha2)) {
1369                 struct wiphy *wiphy = NULL;
1370                 struct cfg80211_registered_device *drv;
1371
1372                 if (last_request->initiator == REGDOM_SET_BY_COUNTRY_IE) {
1373                         if (last_request->wiphy) {
1374                                 wiphy = last_request->wiphy;
1375                                 drv = wiphy_to_dev(wiphy);
1376                                 printk(KERN_INFO "cfg80211: Current regulatory "
1377                                         "domain updated by AP to: %c%c\n",
1378                                         drv->country_ie_alpha2[0],
1379                                         drv->country_ie_alpha2[1]);
1380                         } else
1381                                 printk(KERN_INFO "cfg80211: Current regulatory "
1382                                         "domain intersected: \n");
1383                 } else
1384                                 printk(KERN_INFO "cfg80211: Current regulatory "
1385                                         "domain intersected: \n");
1386         } else if (is_world_regdom(rd->alpha2))
1387                 printk(KERN_INFO "cfg80211: World regulatory "
1388                         "domain updated:\n");
1389         else {
1390                 if (is_unknown_alpha2(rd->alpha2))
1391                         printk(KERN_INFO "cfg80211: Regulatory domain "
1392                                 "changed to driver built-in settings "
1393                                 "(unknown country)\n");
1394                 else
1395                         printk(KERN_INFO "cfg80211: Regulatory domain "
1396                                 "changed to country: %c%c\n",
1397                                 rd->alpha2[0], rd->alpha2[1]);
1398         }
1399         print_rd_rules(rd);
1400 }
1401
1402 static void print_regdomain_info(const struct ieee80211_regdomain *rd)
1403 {
1404         printk(KERN_INFO "cfg80211: Regulatory domain: %c%c\n",
1405                 rd->alpha2[0], rd->alpha2[1]);
1406         print_rd_rules(rd);
1407 }
1408
1409 #ifdef CONFIG_CFG80211_REG_DEBUG
1410 static void reg_country_ie_process_debug(
1411         const struct ieee80211_regdomain *rd,
1412         const struct ieee80211_regdomain *country_ie_regdomain,
1413         const struct ieee80211_regdomain *intersected_rd)
1414 {
1415         printk(KERN_DEBUG "cfg80211: Received country IE:\n");
1416         print_regdomain_info(country_ie_regdomain);
1417         printk(KERN_DEBUG "cfg80211: CRDA thinks this should applied:\n");
1418         print_regdomain_info(rd);
1419         if (intersected_rd) {
1420                 printk(KERN_DEBUG "cfg80211: We intersect both of these "
1421                         "and get:\n");
1422                 print_regdomain_info(intersected_rd);
1423                 return;
1424         }
1425         printk(KERN_DEBUG "cfg80211: Intersection between both failed\n");
1426 }
1427 #else
1428 static inline void reg_country_ie_process_debug(
1429         const struct ieee80211_regdomain *rd,
1430         const struct ieee80211_regdomain *country_ie_regdomain,
1431         const struct ieee80211_regdomain *intersected_rd)
1432 {
1433 }
1434 #endif
1435
1436 /* Takes ownership of rd only if it doesn't fail */
1437 static int __set_regdom(const struct ieee80211_regdomain *rd)
1438 {
1439         const struct ieee80211_regdomain *intersected_rd = NULL;
1440         struct cfg80211_registered_device *drv = NULL;
1441         struct wiphy *wiphy = NULL;
1442         /* Some basic sanity checks first */
1443
1444         if (is_world_regdom(rd->alpha2)) {
1445                 if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
1446                         return -EINVAL;
1447                 update_world_regdomain(rd);
1448                 return 0;
1449         }
1450
1451         if (!is_alpha2_set(rd->alpha2) && !is_an_alpha2(rd->alpha2) &&
1452                         !is_unknown_alpha2(rd->alpha2))
1453                 return -EINVAL;
1454
1455         if (!last_request)
1456                 return -EINVAL;
1457
1458         /* Lets only bother proceeding on the same alpha2 if the current
1459          * rd is non static (it means CRDA was present and was used last)
1460          * and the pending request came in from a country IE */
1461         if (last_request->initiator != REGDOM_SET_BY_COUNTRY_IE) {
1462                 /* If someone else asked us to change the rd lets only bother
1463                  * checking if the alpha2 changes if CRDA was already called */
1464                 if (!is_old_static_regdom(cfg80211_regdomain) &&
1465                     !regdom_changed(rd->alpha2))
1466                         return -EINVAL;
1467         }
1468
1469         wiphy = last_request->wiphy;
1470
1471         /* Now lets set the regulatory domain, update all driver channels
1472          * and finally inform them of what we have done, in case they want
1473          * to review or adjust their own settings based on their own
1474          * internal EEPROM data */
1475
1476         if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
1477                 return -EINVAL;
1478
1479         if (!is_valid_rd(rd)) {
1480                 printk(KERN_ERR "cfg80211: Invalid "
1481                         "regulatory domain detected:\n");
1482                 print_regdomain_info(rd);
1483                 return -EINVAL;
1484         }
1485
1486         if (!last_request->intersect) {
1487                 int r;
1488
1489                 if (last_request->initiator != REGDOM_SET_BY_DRIVER) {
1490                         reset_regdomains();
1491                         cfg80211_regdomain = rd;
1492                         return 0;
1493                 }
1494
1495                 /* For a driver hint, lets copy the regulatory domain the
1496                  * driver wanted to the wiphy to deal with conflicts */
1497
1498                 BUG_ON(last_request->wiphy->regd);
1499
1500                 r = reg_copy_regd(&last_request->wiphy->regd, rd);
1501                 if (r)
1502                         return r;
1503
1504                 reset_regdomains();
1505                 cfg80211_regdomain = rd;
1506                 return 0;
1507         }
1508
1509         /* Intersection requires a bit more work */
1510
1511         if (last_request->initiator != REGDOM_SET_BY_COUNTRY_IE) {
1512
1513                 intersected_rd = regdom_intersect(rd, cfg80211_regdomain);
1514                 if (!intersected_rd)
1515                         return -EINVAL;
1516
1517                 /* We can trash what CRDA provided now.
1518                  * However if a driver requested this specific regulatory
1519                  * domain we keep it for its private use */
1520                 if (last_request->initiator == REGDOM_SET_BY_DRIVER)
1521                         last_request->wiphy->regd = rd;
1522                 else
1523                         kfree(rd);
1524
1525                 rd = NULL;
1526
1527                 reset_regdomains();
1528                 cfg80211_regdomain = intersected_rd;
1529
1530                 return 0;
1531         }
1532
1533         /*
1534          * Country IE requests are handled a bit differently, we intersect
1535          * the country IE rd with what CRDA believes that country should have
1536          */
1537
1538         BUG_ON(!country_ie_regdomain);
1539
1540         if (rd != country_ie_regdomain) {
1541                 /* Intersect what CRDA returned and our what we
1542                  * had built from the Country IE received */
1543
1544                 intersected_rd = regdom_intersect(rd, country_ie_regdomain);
1545
1546                 reg_country_ie_process_debug(rd, country_ie_regdomain,
1547                         intersected_rd);
1548
1549                 kfree(country_ie_regdomain);
1550                 country_ie_regdomain = NULL;
1551         } else {
1552                 /* This would happen when CRDA was not present and
1553                  * OLD_REGULATORY was enabled. We intersect our Country
1554                  * IE rd and what was set on cfg80211 originally */
1555                 intersected_rd = regdom_intersect(rd, cfg80211_regdomain);
1556         }
1557
1558         if (!intersected_rd)
1559                 return -EINVAL;
1560
1561         drv = wiphy_to_dev(wiphy);
1562
1563         drv->country_ie_alpha2[0] = rd->alpha2[0];
1564         drv->country_ie_alpha2[1] = rd->alpha2[1];
1565         drv->env = last_request->country_ie_env;
1566
1567         BUG_ON(intersected_rd == rd);
1568
1569         kfree(rd);
1570         rd = NULL;
1571
1572         reset_regdomains();
1573         cfg80211_regdomain = intersected_rd;
1574
1575         return 0;
1576 }
1577
1578
1579 /* Use this call to set the current regulatory domain. Conflicts with
1580  * multiple drivers can be ironed out later. Caller must've already
1581  * kmalloc'd the rd structure. Caller must hold cfg80211_mutex */
1582 int set_regdom(const struct ieee80211_regdomain *rd)
1583 {
1584         int r;
1585
1586         /* Note that this doesn't update the wiphys, this is done below */
1587         r = __set_regdom(rd);
1588         if (r) {
1589                 kfree(rd);
1590                 return r;
1591         }
1592
1593         /* This would make this whole thing pointless */
1594         if (!last_request->intersect)
1595                 BUG_ON(rd != cfg80211_regdomain);
1596
1597         /* update all wiphys now with the new established regulatory domain */
1598         update_all_wiphy_regulatory(last_request->initiator);
1599
1600         print_regdomain(cfg80211_regdomain);
1601
1602         return r;
1603 }
1604
1605 /* Caller must hold cfg80211_mutex */
1606 void reg_device_remove(struct wiphy *wiphy)
1607 {
1608         kfree(wiphy->regd);
1609         if (!last_request || !last_request->wiphy)
1610                 return;
1611         if (last_request->wiphy != wiphy)
1612                 return;
1613         last_request->wiphy = NULL;
1614         last_request->country_ie_env = ENVIRON_ANY;
1615 }
1616
1617 int regulatory_init(void)
1618 {
1619         int err = 0;
1620
1621         reg_pdev = platform_device_register_simple("regulatory", 0, NULL, 0);
1622         if (IS_ERR(reg_pdev))
1623                 return PTR_ERR(reg_pdev);
1624
1625 #ifdef CONFIG_WIRELESS_OLD_REGULATORY
1626         cfg80211_regdomain = static_regdom(ieee80211_regdom);
1627
1628         printk(KERN_INFO "cfg80211: Using static regulatory domain info\n");
1629         print_regdomain_info(cfg80211_regdomain);
1630         /* The old code still requests for a new regdomain and if
1631          * you have CRDA you get it updated, otherwise you get
1632          * stuck with the static values. We ignore "EU" code as
1633          * that is not a valid ISO / IEC 3166 alpha2 */
1634         if (ieee80211_regdom[0] != 'E' || ieee80211_regdom[1] != 'U')
1635                 err = regulatory_hint_core(ieee80211_regdom);
1636 #else
1637         cfg80211_regdomain = cfg80211_world_regdom;
1638
1639         err = regulatory_hint_core("00");
1640 #endif
1641         if (err) {
1642                 if (err == -ENOMEM)
1643                         return err;
1644                 /*
1645                  * N.B. kobject_uevent_env() can fail mainly for when we're out
1646                  * memory which is handled and propagated appropriately above
1647                  * but it can also fail during a netlink_broadcast() or during
1648                  * early boot for call_usermodehelper(). For now treat these
1649                  * errors as non-fatal.
1650                  */
1651                 printk(KERN_ERR "cfg80211: kobject_uevent_env() was unable "
1652                         "to call CRDA during init");
1653 #ifdef CONFIG_CFG80211_REG_DEBUG
1654                 /* We want to find out exactly why when debugging */
1655                 WARN_ON(err);
1656 #endif
1657         }
1658
1659         return 0;
1660 }
1661
1662 void regulatory_exit(void)
1663 {
1664         mutex_lock(&cfg80211_mutex);
1665
1666         reset_regdomains();
1667
1668         kfree(country_ie_regdomain);
1669         country_ie_regdomain = NULL;
1670
1671         kfree(last_request);
1672
1673         platform_device_unregister(reg_pdev);
1674
1675         mutex_unlock(&cfg80211_mutex);
1676 }