f386981734a01176eb732d933046c4d40c96d133
[linux-2.6.git] / 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/cfg80211.h>
41 #include "core.h"
42 #include "reg.h"
43 #include "nl80211.h"
44
45 /* Receipt of information from last regulatory request */
46 static struct regulatory_request *last_request;
47
48 /* To trigger userspace events */
49 static struct platform_device *reg_pdev;
50
51 /*
52  * Central wireless core regulatory domains, we only need two,
53  * the current one and a world regulatory domain in case we have no
54  * information to give us an alpha2
55  */
56 const struct ieee80211_regdomain *cfg80211_regdomain;
57
58 /*
59  * We use this as a place for the rd structure built from the
60  * last parsed country IE to rest until CRDA gets back to us with
61  * what it thinks should apply for the same country
62  */
63 static const struct ieee80211_regdomain *country_ie_regdomain;
64
65 /* Used to queue up regulatory hints */
66 static LIST_HEAD(reg_requests_list);
67 static spinlock_t reg_requests_lock;
68
69 /* Used to queue up beacon hints for review */
70 static LIST_HEAD(reg_pending_beacons);
71 static spinlock_t reg_pending_beacons_lock;
72
73 /* Used to keep track of processed beacon hints */
74 static LIST_HEAD(reg_beacon_list);
75
76 struct reg_beacon {
77         struct list_head list;
78         struct ieee80211_channel chan;
79 };
80
81 /* We keep a static world regulatory domain in case of the absence of CRDA */
82 static const struct ieee80211_regdomain world_regdom = {
83         .n_reg_rules = 5,
84         .alpha2 =  "00",
85         .reg_rules = {
86                 /* IEEE 802.11b/g, channels 1..11 */
87                 REG_RULE(2412-10, 2462+10, 40, 6, 20, 0),
88                 /* IEEE 802.11b/g, channels 12..13. No HT40
89                  * channel fits here. */
90                 REG_RULE(2467-10, 2472+10, 20, 6, 20,
91                         NL80211_RRF_PASSIVE_SCAN |
92                         NL80211_RRF_NO_IBSS),
93                 /* IEEE 802.11 channel 14 - Only JP enables
94                  * this and for 802.11b only */
95                 REG_RULE(2484-10, 2484+10, 20, 6, 20,
96                         NL80211_RRF_PASSIVE_SCAN |
97                         NL80211_RRF_NO_IBSS |
98                         NL80211_RRF_NO_OFDM),
99                 /* IEEE 802.11a, channel 36..48 */
100                 REG_RULE(5180-10, 5240+10, 40, 6, 20,
101                         NL80211_RRF_PASSIVE_SCAN |
102                         NL80211_RRF_NO_IBSS),
103
104                 /* NB: 5260 MHz - 5700 MHz requies DFS */
105
106                 /* IEEE 802.11a, channel 149..165 */
107                 REG_RULE(5745-10, 5825+10, 40, 6, 20,
108                         NL80211_RRF_PASSIVE_SCAN |
109                         NL80211_RRF_NO_IBSS),
110         }
111 };
112
113 static const struct ieee80211_regdomain *cfg80211_world_regdom =
114         &world_regdom;
115
116 static char *ieee80211_regdom = "00";
117
118 module_param(ieee80211_regdom, charp, 0444);
119 MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain code");
120
121 #ifdef CONFIG_WIRELESS_OLD_REGULATORY
122 /*
123  * We assume 40 MHz bandwidth for the old regulatory work.
124  * We make emphasis we are using the exact same frequencies
125  * as before
126  */
127
128 static const struct ieee80211_regdomain us_regdom = {
129         .n_reg_rules = 6,
130         .alpha2 =  "US",
131         .reg_rules = {
132                 /* IEEE 802.11b/g, channels 1..11 */
133                 REG_RULE(2412-10, 2462+10, 40, 6, 27, 0),
134                 /* IEEE 802.11a, channel 36 */
135                 REG_RULE(5180-10, 5180+10, 40, 6, 23, 0),
136                 /* IEEE 802.11a, channel 40 */
137                 REG_RULE(5200-10, 5200+10, 40, 6, 23, 0),
138                 /* IEEE 802.11a, channel 44 */
139                 REG_RULE(5220-10, 5220+10, 40, 6, 23, 0),
140                 /* IEEE 802.11a, channels 48..64 */
141                 REG_RULE(5240-10, 5320+10, 40, 6, 23, 0),
142                 /* IEEE 802.11a, channels 149..165, outdoor */
143                 REG_RULE(5745-10, 5825+10, 40, 6, 30, 0),
144         }
145 };
146
147 static const struct ieee80211_regdomain jp_regdom = {
148         .n_reg_rules = 3,
149         .alpha2 =  "JP",
150         .reg_rules = {
151                 /* IEEE 802.11b/g, channels 1..14 */
152                 REG_RULE(2412-10, 2484+10, 40, 6, 20, 0),
153                 /* IEEE 802.11a, channels 34..48 */
154                 REG_RULE(5170-10, 5240+10, 40, 6, 20,
155                         NL80211_RRF_PASSIVE_SCAN),
156                 /* IEEE 802.11a, channels 52..64 */
157                 REG_RULE(5260-10, 5320+10, 40, 6, 20,
158                         NL80211_RRF_NO_IBSS |
159                         NL80211_RRF_DFS),
160         }
161 };
162
163 static const struct ieee80211_regdomain eu_regdom = {
164         .n_reg_rules = 6,
165         /*
166          * This alpha2 is bogus, we leave it here just for stupid
167          * backward compatibility
168          */
169         .alpha2 =  "EU",
170         .reg_rules = {
171                 /* IEEE 802.11b/g, channels 1..13 */
172                 REG_RULE(2412-10, 2472+10, 40, 6, 20, 0),
173                 /* IEEE 802.11a, channel 36 */
174                 REG_RULE(5180-10, 5180+10, 40, 6, 23,
175                         NL80211_RRF_PASSIVE_SCAN),
176                 /* IEEE 802.11a, channel 40 */
177                 REG_RULE(5200-10, 5200+10, 40, 6, 23,
178                         NL80211_RRF_PASSIVE_SCAN),
179                 /* IEEE 802.11a, channel 44 */
180                 REG_RULE(5220-10, 5220+10, 40, 6, 23,
181                         NL80211_RRF_PASSIVE_SCAN),
182                 /* IEEE 802.11a, channels 48..64 */
183                 REG_RULE(5240-10, 5320+10, 40, 6, 20,
184                         NL80211_RRF_NO_IBSS |
185                         NL80211_RRF_DFS),
186                 /* IEEE 802.11a, channels 100..140 */
187                 REG_RULE(5500-10, 5700+10, 40, 6, 30,
188                         NL80211_RRF_NO_IBSS |
189                         NL80211_RRF_DFS),
190         }
191 };
192
193 static const struct ieee80211_regdomain *static_regdom(char *alpha2)
194 {
195         if (alpha2[0] == 'U' && alpha2[1] == 'S')
196                 return &us_regdom;
197         if (alpha2[0] == 'J' && alpha2[1] == 'P')
198                 return &jp_regdom;
199         if (alpha2[0] == 'E' && alpha2[1] == 'U')
200                 return &eu_regdom;
201         /* Default, as per the old rules */
202         return &us_regdom;
203 }
204
205 static bool is_old_static_regdom(const struct ieee80211_regdomain *rd)
206 {
207         if (rd == &us_regdom || rd == &jp_regdom || rd == &eu_regdom)
208                 return true;
209         return false;
210 }
211 #else
212 static inline bool is_old_static_regdom(const struct ieee80211_regdomain *rd)
213 {
214         return false;
215 }
216 #endif
217
218 static void reset_regdomains(void)
219 {
220         /* avoid freeing static information or freeing something twice */
221         if (cfg80211_regdomain == cfg80211_world_regdom)
222                 cfg80211_regdomain = NULL;
223         if (cfg80211_world_regdom == &world_regdom)
224                 cfg80211_world_regdom = NULL;
225         if (cfg80211_regdomain == &world_regdom)
226                 cfg80211_regdomain = NULL;
227         if (is_old_static_regdom(cfg80211_regdomain))
228                 cfg80211_regdomain = NULL;
229
230         kfree(cfg80211_regdomain);
231         kfree(cfg80211_world_regdom);
232
233         cfg80211_world_regdom = &world_regdom;
234         cfg80211_regdomain = NULL;
235 }
236
237 /*
238  * Dynamic world regulatory domain requested by the wireless
239  * core upon initialization
240  */
241 static void update_world_regdomain(const struct ieee80211_regdomain *rd)
242 {
243         BUG_ON(!last_request);
244
245         reset_regdomains();
246
247         cfg80211_world_regdom = rd;
248         cfg80211_regdomain = rd;
249 }
250
251 bool is_world_regdom(const char *alpha2)
252 {
253         if (!alpha2)
254                 return false;
255         if (alpha2[0] == '0' && alpha2[1] == '0')
256                 return true;
257         return false;
258 }
259
260 static bool is_alpha2_set(const char *alpha2)
261 {
262         if (!alpha2)
263                 return false;
264         if (alpha2[0] != 0 && alpha2[1] != 0)
265                 return true;
266         return false;
267 }
268
269 static bool is_alpha_upper(char letter)
270 {
271         /* ASCII A - Z */
272         if (letter >= 65 && letter <= 90)
273                 return true;
274         return false;
275 }
276
277 static bool is_unknown_alpha2(const char *alpha2)
278 {
279         if (!alpha2)
280                 return false;
281         /*
282          * Special case where regulatory domain was built by driver
283          * but a specific alpha2 cannot be determined
284          */
285         if (alpha2[0] == '9' && alpha2[1] == '9')
286                 return true;
287         return false;
288 }
289
290 static bool is_intersected_alpha2(const char *alpha2)
291 {
292         if (!alpha2)
293                 return false;
294         /*
295          * Special case where regulatory domain is the
296          * result of an intersection between two regulatory domain
297          * structures
298          */
299         if (alpha2[0] == '9' && alpha2[1] == '8')
300                 return true;
301         return false;
302 }
303
304 static bool is_an_alpha2(const char *alpha2)
305 {
306         if (!alpha2)
307                 return false;
308         if (is_alpha_upper(alpha2[0]) && is_alpha_upper(alpha2[1]))
309                 return true;
310         return false;
311 }
312
313 static bool alpha2_equal(const char *alpha2_x, const char *alpha2_y)
314 {
315         if (!alpha2_x || !alpha2_y)
316                 return false;
317         if (alpha2_x[0] == alpha2_y[0] &&
318                 alpha2_x[1] == alpha2_y[1])
319                 return true;
320         return false;
321 }
322
323 static bool regdom_changes(const char *alpha2)
324 {
325         assert_cfg80211_lock();
326
327         if (!cfg80211_regdomain)
328                 return true;
329         if (alpha2_equal(cfg80211_regdomain->alpha2, alpha2))
330                 return false;
331         return true;
332 }
333
334 /**
335  * country_ie_integrity_changes - tells us if the country IE has changed
336  * @checksum: checksum of country IE of fields we are interested in
337  *
338  * If the country IE has not changed you can ignore it safely. This is
339  * useful to determine if two devices are seeing two different country IEs
340  * even on the same alpha2. Note that this will return false if no IE has
341  * been set on the wireless core yet.
342  */
343 static bool country_ie_integrity_changes(u32 checksum)
344 {
345         /* If no IE has been set then the checksum doesn't change */
346         if (unlikely(!last_request->country_ie_checksum))
347                 return false;
348         if (unlikely(last_request->country_ie_checksum != checksum))
349                 return true;
350         return false;
351 }
352
353 /*
354  * This lets us keep regulatory code which is updated on a regulatory
355  * basis in userspace.
356  */
357 static int call_crda(const char *alpha2)
358 {
359         char country_env[9 + 2] = "COUNTRY=";
360         char *envp[] = {
361                 country_env,
362                 NULL
363         };
364
365         if (!is_world_regdom((char *) alpha2))
366                 printk(KERN_INFO "cfg80211: Calling CRDA for country: %c%c\n",
367                         alpha2[0], alpha2[1]);
368         else
369                 printk(KERN_INFO "cfg80211: Calling CRDA to update world "
370                         "regulatory domain\n");
371
372         country_env[8] = alpha2[0];
373         country_env[9] = alpha2[1];
374
375         return kobject_uevent_env(&reg_pdev->dev.kobj, KOBJ_CHANGE, envp);
376 }
377
378 /* Used by nl80211 before kmalloc'ing our regulatory domain */
379 bool reg_is_valid_request(const char *alpha2)
380 {
381         assert_cfg80211_lock();
382
383         if (!last_request)
384                 return false;
385
386         return alpha2_equal(last_request->alpha2, alpha2);
387 }
388
389 /* Sanity check on a regulatory rule */
390 static bool is_valid_reg_rule(const struct ieee80211_reg_rule *rule)
391 {
392         const struct ieee80211_freq_range *freq_range = &rule->freq_range;
393         u32 freq_diff;
394
395         if (freq_range->start_freq_khz <= 0 || freq_range->end_freq_khz <= 0)
396                 return false;
397
398         if (freq_range->start_freq_khz > freq_range->end_freq_khz)
399                 return false;
400
401         freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
402
403         if (freq_range->end_freq_khz <= freq_range->start_freq_khz ||
404                         freq_range->max_bandwidth_khz > freq_diff)
405                 return false;
406
407         return true;
408 }
409
410 static bool is_valid_rd(const struct ieee80211_regdomain *rd)
411 {
412         const struct ieee80211_reg_rule *reg_rule = NULL;
413         unsigned int i;
414
415         if (!rd->n_reg_rules)
416                 return false;
417
418         if (WARN_ON(rd->n_reg_rules > NL80211_MAX_SUPP_REG_RULES))
419                 return false;
420
421         for (i = 0; i < rd->n_reg_rules; i++) {
422                 reg_rule = &rd->reg_rules[i];
423                 if (!is_valid_reg_rule(reg_rule))
424                         return false;
425         }
426
427         return true;
428 }
429
430 static bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_range,
431                             u32 center_freq_khz,
432                             u32 bw_khz)
433 {
434         u32 start_freq_khz, end_freq_khz;
435
436         start_freq_khz = center_freq_khz - (bw_khz/2);
437         end_freq_khz = center_freq_khz + (bw_khz/2);
438
439         if (start_freq_khz >= freq_range->start_freq_khz &&
440             end_freq_khz <= freq_range->end_freq_khz)
441                 return true;
442
443         return false;
444 }
445
446 /**
447  * freq_in_rule_band - tells us if a frequency is in a frequency band
448  * @freq_range: frequency rule we want to query
449  * @freq_khz: frequency we are inquiring about
450  *
451  * This lets us know if a specific frequency rule is or is not relevant to
452  * a specific frequency's band. Bands are device specific and artificial
453  * definitions (the "2.4 GHz band" and the "5 GHz band"), however it is
454  * safe for now to assume that a frequency rule should not be part of a
455  * frequency's band if the start freq or end freq are off by more than 2 GHz.
456  * This resolution can be lowered and should be considered as we add
457  * regulatory rule support for other "bands".
458  **/
459 static bool freq_in_rule_band(const struct ieee80211_freq_range *freq_range,
460         u32 freq_khz)
461 {
462 #define ONE_GHZ_IN_KHZ  1000000
463         if (abs(freq_khz - freq_range->start_freq_khz) <= (2 * ONE_GHZ_IN_KHZ))
464                 return true;
465         if (abs(freq_khz - freq_range->end_freq_khz) <= (2 * ONE_GHZ_IN_KHZ))
466                 return true;
467         return false;
468 #undef ONE_GHZ_IN_KHZ
469 }
470
471 /*
472  * Converts a country IE to a regulatory domain. A regulatory domain
473  * structure has a lot of information which the IE doesn't yet have,
474  * so for the other values we use upper max values as we will intersect
475  * with our userspace regulatory agent to get lower bounds.
476  */
477 static struct ieee80211_regdomain *country_ie_2_rd(
478                                 u8 *country_ie,
479                                 u8 country_ie_len,
480                                 u32 *checksum)
481 {
482         struct ieee80211_regdomain *rd = NULL;
483         unsigned int i = 0;
484         char alpha2[2];
485         u32 flags = 0;
486         u32 num_rules = 0, size_of_regd = 0;
487         u8 *triplets_start = NULL;
488         u8 len_at_triplet = 0;
489         /* the last channel we have registered in a subband (triplet) */
490         int last_sub_max_channel = 0;
491
492         *checksum = 0xDEADBEEF;
493
494         /* Country IE requirements */
495         BUG_ON(country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN ||
496                 country_ie_len & 0x01);
497
498         alpha2[0] = country_ie[0];
499         alpha2[1] = country_ie[1];
500
501         /*
502          * Third octet can be:
503          *    'I' - Indoor
504          *    'O' - Outdoor
505          *
506          *  anything else we assume is no restrictions
507          */
508         if (country_ie[2] == 'I')
509                 flags = NL80211_RRF_NO_OUTDOOR;
510         else if (country_ie[2] == 'O')
511                 flags = NL80211_RRF_NO_INDOOR;
512
513         country_ie += 3;
514         country_ie_len -= 3;
515
516         triplets_start = country_ie;
517         len_at_triplet = country_ie_len;
518
519         *checksum ^= ((flags ^ alpha2[0] ^ alpha2[1]) << 8);
520
521         /*
522          * We need to build a reg rule for each triplet, but first we must
523          * calculate the number of reg rules we will need. We will need one
524          * for each channel subband
525          */
526         while (country_ie_len >= 3) {
527                 int end_channel = 0;
528                 struct ieee80211_country_ie_triplet *triplet =
529                         (struct ieee80211_country_ie_triplet *) country_ie;
530                 int cur_sub_max_channel = 0, cur_channel = 0;
531
532                 if (triplet->ext.reg_extension_id >=
533                                 IEEE80211_COUNTRY_EXTENSION_ID) {
534                         country_ie += 3;
535                         country_ie_len -= 3;
536                         continue;
537                 }
538
539                 /* 2 GHz */
540                 if (triplet->chans.first_channel <= 14)
541                         end_channel = triplet->chans.first_channel +
542                                 triplet->chans.num_channels;
543                 else
544                         /*
545                          * 5 GHz -- For example in country IEs if the first
546                          * channel given is 36 and the number of channels is 4
547                          * then the individual channel numbers defined for the
548                          * 5 GHz PHY by these parameters are: 36, 40, 44, and 48
549                          * and not 36, 37, 38, 39.
550                          *
551                          * See: http://tinyurl.com/11d-clarification
552                          */
553                         end_channel =  triplet->chans.first_channel +
554                                 (4 * (triplet->chans.num_channels - 1));
555
556                 cur_channel = triplet->chans.first_channel;
557                 cur_sub_max_channel = end_channel;
558
559                 /* Basic sanity check */
560                 if (cur_sub_max_channel < cur_channel)
561                         return NULL;
562
563                 /*
564                  * Do not allow overlapping channels. Also channels
565                  * passed in each subband must be monotonically
566                  * increasing
567                  */
568                 if (last_sub_max_channel) {
569                         if (cur_channel <= last_sub_max_channel)
570                                 return NULL;
571                         if (cur_sub_max_channel <= last_sub_max_channel)
572                                 return NULL;
573                 }
574
575                 /*
576                  * When dot11RegulatoryClassesRequired is supported
577                  * we can throw ext triplets as part of this soup,
578                  * for now we don't care when those change as we
579                  * don't support them
580                  */
581                 *checksum ^= ((cur_channel ^ cur_sub_max_channel) << 8) |
582                   ((cur_sub_max_channel ^ cur_sub_max_channel) << 16) |
583                   ((triplet->chans.max_power ^ cur_sub_max_channel) << 24);
584
585                 last_sub_max_channel = cur_sub_max_channel;
586
587                 country_ie += 3;
588                 country_ie_len -= 3;
589                 num_rules++;
590
591                 /*
592                  * Note: this is not a IEEE requirement but
593                  * simply a memory requirement
594                  */
595                 if (num_rules > NL80211_MAX_SUPP_REG_RULES)
596                         return NULL;
597         }
598
599         country_ie = triplets_start;
600         country_ie_len = len_at_triplet;
601
602         size_of_regd = sizeof(struct ieee80211_regdomain) +
603                 (num_rules * sizeof(struct ieee80211_reg_rule));
604
605         rd = kzalloc(size_of_regd, GFP_KERNEL);
606         if (!rd)
607                 return NULL;
608
609         rd->n_reg_rules = num_rules;
610         rd->alpha2[0] = alpha2[0];
611         rd->alpha2[1] = alpha2[1];
612
613         /* This time around we fill in the rd */
614         while (country_ie_len >= 3) {
615                 int end_channel = 0;
616                 struct ieee80211_country_ie_triplet *triplet =
617                         (struct ieee80211_country_ie_triplet *) country_ie;
618                 struct ieee80211_reg_rule *reg_rule = NULL;
619                 struct ieee80211_freq_range *freq_range = NULL;
620                 struct ieee80211_power_rule *power_rule = NULL;
621
622                 /*
623                  * Must parse if dot11RegulatoryClassesRequired is true,
624                  * we don't support this yet
625                  */
626                 if (triplet->ext.reg_extension_id >=
627                                 IEEE80211_COUNTRY_EXTENSION_ID) {
628                         country_ie += 3;
629                         country_ie_len -= 3;
630                         continue;
631                 }
632
633                 reg_rule = &rd->reg_rules[i];
634                 freq_range = &reg_rule->freq_range;
635                 power_rule = &reg_rule->power_rule;
636
637                 reg_rule->flags = flags;
638
639                 /* 2 GHz */
640                 if (triplet->chans.first_channel <= 14)
641                         end_channel = triplet->chans.first_channel +
642                                 triplet->chans.num_channels;
643                 else
644                         end_channel =  triplet->chans.first_channel +
645                                 (4 * (triplet->chans.num_channels - 1));
646
647                 /*
648                  * The +10 is since the regulatory domain expects
649                  * the actual band edge, not the center of freq for
650                  * its start and end freqs, assuming 20 MHz bandwidth on
651                  * the channels passed
652                  */
653                 freq_range->start_freq_khz =
654                         MHZ_TO_KHZ(ieee80211_channel_to_frequency(
655                                 triplet->chans.first_channel) - 10);
656                 freq_range->end_freq_khz =
657                         MHZ_TO_KHZ(ieee80211_channel_to_frequency(
658                                 end_channel) + 10);
659
660                 /*
661                  * These are large arbitrary values we use to intersect later.
662                  * Increment this if we ever support >= 40 MHz channels
663                  * in IEEE 802.11
664                  */
665                 freq_range->max_bandwidth_khz = MHZ_TO_KHZ(40);
666                 power_rule->max_antenna_gain = DBI_TO_MBI(100);
667                 power_rule->max_eirp = DBM_TO_MBM(100);
668
669                 country_ie += 3;
670                 country_ie_len -= 3;
671                 i++;
672
673                 BUG_ON(i > NL80211_MAX_SUPP_REG_RULES);
674         }
675
676         return rd;
677 }
678
679
680 /*
681  * Helper for regdom_intersect(), this does the real
682  * mathematical intersection fun
683  */
684 static int reg_rules_intersect(
685         const struct ieee80211_reg_rule *rule1,
686         const struct ieee80211_reg_rule *rule2,
687         struct ieee80211_reg_rule *intersected_rule)
688 {
689         const struct ieee80211_freq_range *freq_range1, *freq_range2;
690         struct ieee80211_freq_range *freq_range;
691         const struct ieee80211_power_rule *power_rule1, *power_rule2;
692         struct ieee80211_power_rule *power_rule;
693         u32 freq_diff;
694
695         freq_range1 = &rule1->freq_range;
696         freq_range2 = &rule2->freq_range;
697         freq_range = &intersected_rule->freq_range;
698
699         power_rule1 = &rule1->power_rule;
700         power_rule2 = &rule2->power_rule;
701         power_rule = &intersected_rule->power_rule;
702
703         freq_range->start_freq_khz = max(freq_range1->start_freq_khz,
704                 freq_range2->start_freq_khz);
705         freq_range->end_freq_khz = min(freq_range1->end_freq_khz,
706                 freq_range2->end_freq_khz);
707         freq_range->max_bandwidth_khz = min(freq_range1->max_bandwidth_khz,
708                 freq_range2->max_bandwidth_khz);
709
710         freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
711         if (freq_range->max_bandwidth_khz > freq_diff)
712                 freq_range->max_bandwidth_khz = freq_diff;
713
714         power_rule->max_eirp = min(power_rule1->max_eirp,
715                 power_rule2->max_eirp);
716         power_rule->max_antenna_gain = min(power_rule1->max_antenna_gain,
717                 power_rule2->max_antenna_gain);
718
719         intersected_rule->flags = (rule1->flags | rule2->flags);
720
721         if (!is_valid_reg_rule(intersected_rule))
722                 return -EINVAL;
723
724         return 0;
725 }
726
727 /**
728  * regdom_intersect - do the intersection between two regulatory domains
729  * @rd1: first regulatory domain
730  * @rd2: second regulatory domain
731  *
732  * Use this function to get the intersection between two regulatory domains.
733  * Once completed we will mark the alpha2 for the rd as intersected, "98",
734  * as no one single alpha2 can represent this regulatory domain.
735  *
736  * Returns a pointer to the regulatory domain structure which will hold the
737  * resulting intersection of rules between rd1 and rd2. We will
738  * kzalloc() this structure for you.
739  */
740 static struct ieee80211_regdomain *regdom_intersect(
741         const struct ieee80211_regdomain *rd1,
742         const struct ieee80211_regdomain *rd2)
743 {
744         int r, size_of_regd;
745         unsigned int x, y;
746         unsigned int num_rules = 0, rule_idx = 0;
747         const struct ieee80211_reg_rule *rule1, *rule2;
748         struct ieee80211_reg_rule *intersected_rule;
749         struct ieee80211_regdomain *rd;
750         /* This is just a dummy holder to help us count */
751         struct ieee80211_reg_rule irule;
752
753         /* Uses the stack temporarily for counter arithmetic */
754         intersected_rule = &irule;
755
756         memset(intersected_rule, 0, sizeof(struct ieee80211_reg_rule));
757
758         if (!rd1 || !rd2)
759                 return NULL;
760
761         /*
762          * First we get a count of the rules we'll need, then we actually
763          * build them. This is to so we can malloc() and free() a
764          * regdomain once. The reason we use reg_rules_intersect() here
765          * is it will return -EINVAL if the rule computed makes no sense.
766          * All rules that do check out OK are valid.
767          */
768
769         for (x = 0; x < rd1->n_reg_rules; x++) {
770                 rule1 = &rd1->reg_rules[x];
771                 for (y = 0; y < rd2->n_reg_rules; y++) {
772                         rule2 = &rd2->reg_rules[y];
773                         if (!reg_rules_intersect(rule1, rule2,
774                                         intersected_rule))
775                                 num_rules++;
776                         memset(intersected_rule, 0,
777                                         sizeof(struct ieee80211_reg_rule));
778                 }
779         }
780
781         if (!num_rules)
782                 return NULL;
783
784         size_of_regd = sizeof(struct ieee80211_regdomain) +
785                 ((num_rules + 1) * sizeof(struct ieee80211_reg_rule));
786
787         rd = kzalloc(size_of_regd, GFP_KERNEL);
788         if (!rd)
789                 return NULL;
790
791         for (x = 0; x < rd1->n_reg_rules; x++) {
792                 rule1 = &rd1->reg_rules[x];
793                 for (y = 0; y < rd2->n_reg_rules; y++) {
794                         rule2 = &rd2->reg_rules[y];
795                         /*
796                          * This time around instead of using the stack lets
797                          * write to the target rule directly saving ourselves
798                          * a memcpy()
799                          */
800                         intersected_rule = &rd->reg_rules[rule_idx];
801                         r = reg_rules_intersect(rule1, rule2,
802                                 intersected_rule);
803                         /*
804                          * No need to memset here the intersected rule here as
805                          * we're not using the stack anymore
806                          */
807                         if (r)
808                                 continue;
809                         rule_idx++;
810                 }
811         }
812
813         if (rule_idx != num_rules) {
814                 kfree(rd);
815                 return NULL;
816         }
817
818         rd->n_reg_rules = num_rules;
819         rd->alpha2[0] = '9';
820         rd->alpha2[1] = '8';
821
822         return rd;
823 }
824
825 /*
826  * XXX: add support for the rest of enum nl80211_reg_rule_flags, we may
827  * want to just have the channel structure use these
828  */
829 static u32 map_regdom_flags(u32 rd_flags)
830 {
831         u32 channel_flags = 0;
832         if (rd_flags & NL80211_RRF_PASSIVE_SCAN)
833                 channel_flags |= IEEE80211_CHAN_PASSIVE_SCAN;
834         if (rd_flags & NL80211_RRF_NO_IBSS)
835                 channel_flags |= IEEE80211_CHAN_NO_IBSS;
836         if (rd_flags & NL80211_RRF_DFS)
837                 channel_flags |= IEEE80211_CHAN_RADAR;
838         return channel_flags;
839 }
840
841 static int freq_reg_info_regd(struct wiphy *wiphy,
842                               u32 center_freq,
843                               u32 desired_bw_khz,
844                               const struct ieee80211_reg_rule **reg_rule,
845                               const struct ieee80211_regdomain *custom_regd)
846 {
847         int i;
848         bool band_rule_found = false;
849         const struct ieee80211_regdomain *regd;
850         bool bw_fits = false;
851
852         if (!desired_bw_khz)
853                 desired_bw_khz = MHZ_TO_KHZ(20);
854
855         regd = custom_regd ? custom_regd : cfg80211_regdomain;
856
857         /*
858          * Follow the driver's regulatory domain, if present, unless a country
859          * IE has been processed or a user wants to help complaince further
860          */
861         if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
862             last_request->initiator != NL80211_REGDOM_SET_BY_USER &&
863             wiphy->regd)
864                 regd = wiphy->regd;
865
866         if (!regd)
867                 return -EINVAL;
868
869         for (i = 0; i < regd->n_reg_rules; i++) {
870                 const struct ieee80211_reg_rule *rr;
871                 const struct ieee80211_freq_range *fr = NULL;
872                 const struct ieee80211_power_rule *pr = NULL;
873
874                 rr = &regd->reg_rules[i];
875                 fr = &rr->freq_range;
876                 pr = &rr->power_rule;
877
878                 /*
879                  * We only need to know if one frequency rule was
880                  * was in center_freq's band, that's enough, so lets
881                  * not overwrite it once found
882                  */
883                 if (!band_rule_found)
884                         band_rule_found = freq_in_rule_band(fr, center_freq);
885
886                 bw_fits = reg_does_bw_fit(fr,
887                                           center_freq,
888                                           desired_bw_khz);
889
890                 if (band_rule_found && bw_fits) {
891                         *reg_rule = rr;
892                         return 0;
893                 }
894         }
895
896         if (!band_rule_found)
897                 return -ERANGE;
898
899         return -EINVAL;
900 }
901 EXPORT_SYMBOL(freq_reg_info);
902
903 int freq_reg_info(struct wiphy *wiphy,
904                   u32 center_freq,
905                   u32 desired_bw_khz,
906                   const struct ieee80211_reg_rule **reg_rule)
907 {
908         assert_cfg80211_lock();
909         return freq_reg_info_regd(wiphy,
910                                   center_freq,
911                                   desired_bw_khz,
912                                   reg_rule,
913                                   NULL);
914 }
915
916 /*
917  * Note that right now we assume the desired channel bandwidth
918  * is always 20 MHz for each individual channel (HT40 uses 20 MHz
919  * per channel, the primary and the extension channel). To support
920  * smaller custom bandwidths such as 5 MHz or 10 MHz we'll need a
921  * new ieee80211_channel.target_bw and re run the regulatory check
922  * on the wiphy with the target_bw specified. Then we can simply use
923  * that below for the desired_bw_khz below.
924  */
925 static void handle_channel(struct wiphy *wiphy, enum ieee80211_band band,
926                            unsigned int chan_idx)
927 {
928         int r;
929         u32 flags, bw_flags = 0;
930         u32 desired_bw_khz = MHZ_TO_KHZ(20);
931         const struct ieee80211_reg_rule *reg_rule = NULL;
932         const struct ieee80211_power_rule *power_rule = NULL;
933         const struct ieee80211_freq_range *freq_range = NULL;
934         struct ieee80211_supported_band *sband;
935         struct ieee80211_channel *chan;
936         struct wiphy *request_wiphy = NULL;
937
938         assert_cfg80211_lock();
939
940         request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
941
942         sband = wiphy->bands[band];
943         BUG_ON(chan_idx >= sband->n_channels);
944         chan = &sband->channels[chan_idx];
945
946         flags = chan->orig_flags;
947
948         r = freq_reg_info(wiphy,
949                           MHZ_TO_KHZ(chan->center_freq),
950                           desired_bw_khz,
951                           &reg_rule);
952
953         if (r) {
954                 /*
955                  * This means no regulatory rule was found in the country IE
956                  * with a frequency range on the center_freq's band, since
957                  * IEEE-802.11 allows for a country IE to have a subset of the
958                  * regulatory information provided in a country we ignore
959                  * disabling the channel unless at least one reg rule was
960                  * found on the center_freq's band. For details see this
961                  * clarification:
962                  *
963                  * http://tinyurl.com/11d-clarification
964                  */
965                 if (r == -ERANGE &&
966                     last_request->initiator ==
967                     NL80211_REGDOM_SET_BY_COUNTRY_IE) {
968 #ifdef CONFIG_CFG80211_REG_DEBUG
969                         printk(KERN_DEBUG "cfg80211: Leaving channel %d MHz "
970                                 "intact on %s - no rule found in band on "
971                                 "Country IE\n",
972                                 chan->center_freq, wiphy_name(wiphy));
973 #endif
974                 } else {
975                 /*
976                  * In this case we know the country IE has at least one reg rule
977                  * for the band so we respect its band definitions
978                  */
979 #ifdef CONFIG_CFG80211_REG_DEBUG
980                         if (last_request->initiator ==
981                             NL80211_REGDOM_SET_BY_COUNTRY_IE)
982                                 printk(KERN_DEBUG "cfg80211: Disabling "
983                                         "channel %d MHz on %s due to "
984                                         "Country IE\n",
985                                         chan->center_freq, wiphy_name(wiphy));
986 #endif
987                         flags |= IEEE80211_CHAN_DISABLED;
988                         chan->flags = flags;
989                 }
990                 return;
991         }
992
993         power_rule = &reg_rule->power_rule;
994         freq_range = &reg_rule->freq_range;
995
996         if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
997                 bw_flags = IEEE80211_CHAN_NO_HT40;
998
999         if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1000             request_wiphy && request_wiphy == wiphy &&
1001             request_wiphy->strict_regulatory) {
1002                 /*
1003                  * This gaurantees the driver's requested regulatory domain
1004                  * will always be used as a base for further regulatory
1005                  * settings
1006                  */
1007                 chan->flags = chan->orig_flags =
1008                         map_regdom_flags(reg_rule->flags) | bw_flags;
1009                 chan->max_antenna_gain = chan->orig_mag =
1010                         (int) MBI_TO_DBI(power_rule->max_antenna_gain);
1011                 chan->max_bandwidth = KHZ_TO_MHZ(desired_bw_khz);
1012                 chan->max_power = chan->orig_mpwr =
1013                         (int) MBM_TO_DBM(power_rule->max_eirp);
1014                 return;
1015         }
1016
1017         chan->flags = flags | bw_flags | map_regdom_flags(reg_rule->flags);
1018         chan->max_antenna_gain = min(chan->orig_mag,
1019                 (int) MBI_TO_DBI(power_rule->max_antenna_gain));
1020         chan->max_bandwidth = KHZ_TO_MHZ(desired_bw_khz);
1021         if (chan->orig_mpwr)
1022                 chan->max_power = min(chan->orig_mpwr,
1023                         (int) MBM_TO_DBM(power_rule->max_eirp));
1024         else
1025                 chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
1026 }
1027
1028 static void handle_band(struct wiphy *wiphy, enum ieee80211_band band)
1029 {
1030         unsigned int i;
1031         struct ieee80211_supported_band *sband;
1032
1033         BUG_ON(!wiphy->bands[band]);
1034         sband = wiphy->bands[band];
1035
1036         for (i = 0; i < sband->n_channels; i++)
1037                 handle_channel(wiphy, band, i);
1038 }
1039
1040 static bool ignore_reg_update(struct wiphy *wiphy,
1041                               enum nl80211_reg_initiator initiator)
1042 {
1043         if (!last_request)
1044                 return true;
1045         if (initiator == NL80211_REGDOM_SET_BY_CORE &&
1046                   wiphy->custom_regulatory)
1047                 return true;
1048         /*
1049          * wiphy->regd will be set once the device has its own
1050          * desired regulatory domain set
1051          */
1052         if (wiphy->strict_regulatory && !wiphy->regd &&
1053             !is_world_regdom(last_request->alpha2))
1054                 return true;
1055         return false;
1056 }
1057
1058 static void update_all_wiphy_regulatory(enum nl80211_reg_initiator initiator)
1059 {
1060         struct cfg80211_registered_device *rdev;
1061
1062         list_for_each_entry(rdev, &cfg80211_rdev_list, list)
1063                 wiphy_update_regulatory(&rdev->wiphy, initiator);
1064 }
1065
1066 static void handle_reg_beacon(struct wiphy *wiphy,
1067                               unsigned int chan_idx,
1068                               struct reg_beacon *reg_beacon)
1069 {
1070         struct ieee80211_supported_band *sband;
1071         struct ieee80211_channel *chan;
1072         bool channel_changed = false;
1073         struct ieee80211_channel chan_before;
1074
1075         assert_cfg80211_lock();
1076
1077         sband = wiphy->bands[reg_beacon->chan.band];
1078         chan = &sband->channels[chan_idx];
1079
1080         if (likely(chan->center_freq != reg_beacon->chan.center_freq))
1081                 return;
1082
1083         if (chan->beacon_found)
1084                 return;
1085
1086         chan->beacon_found = true;
1087
1088         chan_before.center_freq = chan->center_freq;
1089         chan_before.flags = chan->flags;
1090
1091         if ((chan->flags & IEEE80211_CHAN_PASSIVE_SCAN) &&
1092             !(chan->orig_flags & IEEE80211_CHAN_PASSIVE_SCAN)) {
1093                 chan->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
1094                 channel_changed = true;
1095         }
1096
1097         if ((chan->flags & IEEE80211_CHAN_NO_IBSS) &&
1098             !(chan->orig_flags & IEEE80211_CHAN_NO_IBSS)) {
1099                 chan->flags &= ~IEEE80211_CHAN_NO_IBSS;
1100                 channel_changed = true;
1101         }
1102
1103         if (channel_changed)
1104                 nl80211_send_beacon_hint_event(wiphy, &chan_before, chan);
1105 }
1106
1107 /*
1108  * Called when a scan on a wiphy finds a beacon on
1109  * new channel
1110  */
1111 static void wiphy_update_new_beacon(struct wiphy *wiphy,
1112                                     struct reg_beacon *reg_beacon)
1113 {
1114         unsigned int i;
1115         struct ieee80211_supported_band *sband;
1116
1117         assert_cfg80211_lock();
1118
1119         if (!wiphy->bands[reg_beacon->chan.band])
1120                 return;
1121
1122         sband = wiphy->bands[reg_beacon->chan.band];
1123
1124         for (i = 0; i < sband->n_channels; i++)
1125                 handle_reg_beacon(wiphy, i, reg_beacon);
1126 }
1127
1128 /*
1129  * Called upon reg changes or a new wiphy is added
1130  */
1131 static void wiphy_update_beacon_reg(struct wiphy *wiphy)
1132 {
1133         unsigned int i;
1134         struct ieee80211_supported_band *sband;
1135         struct reg_beacon *reg_beacon;
1136
1137         assert_cfg80211_lock();
1138
1139         if (list_empty(&reg_beacon_list))
1140                 return;
1141
1142         list_for_each_entry(reg_beacon, &reg_beacon_list, list) {
1143                 if (!wiphy->bands[reg_beacon->chan.band])
1144                         continue;
1145                 sband = wiphy->bands[reg_beacon->chan.band];
1146                 for (i = 0; i < sband->n_channels; i++)
1147                         handle_reg_beacon(wiphy, i, reg_beacon);
1148         }
1149 }
1150
1151 static bool reg_is_world_roaming(struct wiphy *wiphy)
1152 {
1153         if (is_world_regdom(cfg80211_regdomain->alpha2) ||
1154             (wiphy->regd && is_world_regdom(wiphy->regd->alpha2)))
1155                 return true;
1156         if (last_request &&
1157             last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1158             wiphy->custom_regulatory)
1159                 return true;
1160         return false;
1161 }
1162
1163 /* Reap the advantages of previously found beacons */
1164 static void reg_process_beacons(struct wiphy *wiphy)
1165 {
1166         /*
1167          * Means we are just firing up cfg80211, so no beacons would
1168          * have been processed yet.
1169          */
1170         if (!last_request)
1171                 return;
1172         if (!reg_is_world_roaming(wiphy))
1173                 return;
1174         wiphy_update_beacon_reg(wiphy);
1175 }
1176
1177 static bool is_ht40_not_allowed(struct ieee80211_channel *chan)
1178 {
1179         if (!chan)
1180                 return true;
1181         if (chan->flags & IEEE80211_CHAN_DISABLED)
1182                 return true;
1183         /* This would happen when regulatory rules disallow HT40 completely */
1184         if (IEEE80211_CHAN_NO_HT40 == (chan->flags & (IEEE80211_CHAN_NO_HT40)))
1185                 return true;
1186         return false;
1187 }
1188
1189 static void reg_process_ht_flags_channel(struct wiphy *wiphy,
1190                                          enum ieee80211_band band,
1191                                          unsigned int chan_idx)
1192 {
1193         struct ieee80211_supported_band *sband;
1194         struct ieee80211_channel *channel;
1195         struct ieee80211_channel *channel_before = NULL, *channel_after = NULL;
1196         unsigned int i;
1197
1198         assert_cfg80211_lock();
1199
1200         sband = wiphy->bands[band];
1201         BUG_ON(chan_idx >= sband->n_channels);
1202         channel = &sband->channels[chan_idx];
1203
1204         if (is_ht40_not_allowed(channel)) {
1205                 channel->flags |= IEEE80211_CHAN_NO_HT40;
1206                 return;
1207         }
1208
1209         /*
1210          * We need to ensure the extension channels exist to
1211          * be able to use HT40- or HT40+, this finds them (or not)
1212          */
1213         for (i = 0; i < sband->n_channels; i++) {
1214                 struct ieee80211_channel *c = &sband->channels[i];
1215                 if (c->center_freq == (channel->center_freq - 20))
1216                         channel_before = c;
1217                 if (c->center_freq == (channel->center_freq + 20))
1218                         channel_after = c;
1219         }
1220
1221         /*
1222          * Please note that this assumes target bandwidth is 20 MHz,
1223          * if that ever changes we also need to change the below logic
1224          * to include that as well.
1225          */
1226         if (is_ht40_not_allowed(channel_before))
1227                 channel->flags |= IEEE80211_CHAN_NO_HT40MINUS;
1228         else
1229                 channel->flags &= ~IEEE80211_CHAN_NO_HT40MINUS;
1230
1231         if (is_ht40_not_allowed(channel_after))
1232                 channel->flags |= IEEE80211_CHAN_NO_HT40PLUS;
1233         else
1234                 channel->flags &= ~IEEE80211_CHAN_NO_HT40PLUS;
1235 }
1236
1237 static void reg_process_ht_flags_band(struct wiphy *wiphy,
1238                                       enum ieee80211_band band)
1239 {
1240         unsigned int i;
1241         struct ieee80211_supported_band *sband;
1242
1243         BUG_ON(!wiphy->bands[band]);
1244         sband = wiphy->bands[band];
1245
1246         for (i = 0; i < sband->n_channels; i++)
1247                 reg_process_ht_flags_channel(wiphy, band, i);
1248 }
1249
1250 static void reg_process_ht_flags(struct wiphy *wiphy)
1251 {
1252         enum ieee80211_band band;
1253
1254         if (!wiphy)
1255                 return;
1256
1257         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1258                 if (wiphy->bands[band])
1259                         reg_process_ht_flags_band(wiphy, band);
1260         }
1261
1262 }
1263
1264 void wiphy_update_regulatory(struct wiphy *wiphy,
1265                              enum nl80211_reg_initiator initiator)
1266 {
1267         enum ieee80211_band band;
1268
1269         if (ignore_reg_update(wiphy, initiator))
1270                 goto out;
1271         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1272                 if (wiphy->bands[band])
1273                         handle_band(wiphy, band);
1274         }
1275 out:
1276         reg_process_beacons(wiphy);
1277         reg_process_ht_flags(wiphy);
1278         if (wiphy->reg_notifier)
1279                 wiphy->reg_notifier(wiphy, last_request);
1280 }
1281
1282 static void handle_channel_custom(struct wiphy *wiphy,
1283                                   enum ieee80211_band band,
1284                                   unsigned int chan_idx,
1285                                   const struct ieee80211_regdomain *regd)
1286 {
1287         int r;
1288         u32 desired_bw_khz = MHZ_TO_KHZ(20);
1289         u32 bw_flags = 0;
1290         const struct ieee80211_reg_rule *reg_rule = NULL;
1291         const struct ieee80211_power_rule *power_rule = NULL;
1292         const struct ieee80211_freq_range *freq_range = NULL;
1293         struct ieee80211_supported_band *sband;
1294         struct ieee80211_channel *chan;
1295
1296         assert_cfg80211_lock();
1297
1298         sband = wiphy->bands[band];
1299         BUG_ON(chan_idx >= sband->n_channels);
1300         chan = &sband->channels[chan_idx];
1301
1302         r = freq_reg_info_regd(wiphy,
1303                                MHZ_TO_KHZ(chan->center_freq),
1304                                desired_bw_khz,
1305                                &reg_rule,
1306                                regd);
1307
1308         if (r) {
1309                 chan->flags = IEEE80211_CHAN_DISABLED;
1310                 return;
1311         }
1312
1313         power_rule = &reg_rule->power_rule;
1314         freq_range = &reg_rule->freq_range;
1315
1316         if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
1317                 bw_flags = IEEE80211_CHAN_NO_HT40;
1318
1319         chan->flags |= map_regdom_flags(reg_rule->flags) | bw_flags;
1320         chan->max_antenna_gain = (int) MBI_TO_DBI(power_rule->max_antenna_gain);
1321         chan->max_bandwidth = KHZ_TO_MHZ(desired_bw_khz);
1322         chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
1323 }
1324
1325 static void handle_band_custom(struct wiphy *wiphy, enum ieee80211_band band,
1326                                const struct ieee80211_regdomain *regd)
1327 {
1328         unsigned int i;
1329         struct ieee80211_supported_band *sband;
1330
1331         BUG_ON(!wiphy->bands[band]);
1332         sband = wiphy->bands[band];
1333
1334         for (i = 0; i < sband->n_channels; i++)
1335                 handle_channel_custom(wiphy, band, i, regd);
1336 }
1337
1338 /* Used by drivers prior to wiphy registration */
1339 void wiphy_apply_custom_regulatory(struct wiphy *wiphy,
1340                                    const struct ieee80211_regdomain *regd)
1341 {
1342         enum ieee80211_band band;
1343         unsigned int bands_set = 0;
1344
1345         mutex_lock(&cfg80211_mutex);
1346         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1347                 if (!wiphy->bands[band])
1348                         continue;
1349                 handle_band_custom(wiphy, band, regd);
1350                 bands_set++;
1351         }
1352         mutex_unlock(&cfg80211_mutex);
1353
1354         /*
1355          * no point in calling this if it won't have any effect
1356          * on your device's supportd bands.
1357          */
1358         WARN_ON(!bands_set);
1359 }
1360 EXPORT_SYMBOL(wiphy_apply_custom_regulatory);
1361
1362 static int reg_copy_regd(const struct ieee80211_regdomain **dst_regd,
1363                          const struct ieee80211_regdomain *src_regd)
1364 {
1365         struct ieee80211_regdomain *regd;
1366         int size_of_regd = 0;
1367         unsigned int i;
1368
1369         size_of_regd = sizeof(struct ieee80211_regdomain) +
1370           ((src_regd->n_reg_rules + 1) * sizeof(struct ieee80211_reg_rule));
1371
1372         regd = kzalloc(size_of_regd, GFP_KERNEL);
1373         if (!regd)
1374                 return -ENOMEM;
1375
1376         memcpy(regd, src_regd, sizeof(struct ieee80211_regdomain));
1377
1378         for (i = 0; i < src_regd->n_reg_rules; i++)
1379                 memcpy(&regd->reg_rules[i], &src_regd->reg_rules[i],
1380                         sizeof(struct ieee80211_reg_rule));
1381
1382         *dst_regd = regd;
1383         return 0;
1384 }
1385
1386 /*
1387  * Return value which can be used by ignore_request() to indicate
1388  * it has been determined we should intersect two regulatory domains
1389  */
1390 #define REG_INTERSECT   1
1391
1392 /* This has the logic which determines when a new request
1393  * should be ignored. */
1394 static int ignore_request(struct wiphy *wiphy,
1395                           struct regulatory_request *pending_request)
1396 {
1397         struct wiphy *last_wiphy = NULL;
1398
1399         assert_cfg80211_lock();
1400
1401         /* All initial requests are respected */
1402         if (!last_request)
1403                 return 0;
1404
1405         switch (pending_request->initiator) {
1406         case NL80211_REGDOM_SET_BY_CORE:
1407                 return -EINVAL;
1408         case NL80211_REGDOM_SET_BY_COUNTRY_IE:
1409
1410                 last_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
1411
1412                 if (unlikely(!is_an_alpha2(pending_request->alpha2)))
1413                         return -EINVAL;
1414                 if (last_request->initiator ==
1415                     NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1416                         if (last_wiphy != wiphy) {
1417                                 /*
1418                                  * Two cards with two APs claiming different
1419                                  * different Country IE alpha2s. We could
1420                                  * intersect them, but that seems unlikely
1421                                  * to be correct. Reject second one for now.
1422                                  */
1423                                 if (regdom_changes(pending_request->alpha2))
1424                                         return -EOPNOTSUPP;
1425                                 return -EALREADY;
1426                         }
1427                         /*
1428                          * Two consecutive Country IE hints on the same wiphy.
1429                          * This should be picked up early by the driver/stack
1430                          */
1431                         if (WARN_ON(regdom_changes(pending_request->alpha2)))
1432                                 return 0;
1433                         return -EALREADY;
1434                 }
1435                 return REG_INTERSECT;
1436         case NL80211_REGDOM_SET_BY_DRIVER:
1437                 if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE) {
1438                         if (is_old_static_regdom(cfg80211_regdomain))
1439                                 return 0;
1440                         if (regdom_changes(pending_request->alpha2))
1441                                 return 0;
1442                         return -EALREADY;
1443                 }
1444
1445                 /*
1446                  * This would happen if you unplug and plug your card
1447                  * back in or if you add a new device for which the previously
1448                  * loaded card also agrees on the regulatory domain.
1449                  */
1450                 if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1451                     !regdom_changes(pending_request->alpha2))
1452                         return -EALREADY;
1453
1454                 return REG_INTERSECT;
1455         case NL80211_REGDOM_SET_BY_USER:
1456                 if (last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE)
1457                         return REG_INTERSECT;
1458                 /*
1459                  * If the user knows better the user should set the regdom
1460                  * to their country before the IE is picked up
1461                  */
1462                 if (last_request->initiator == NL80211_REGDOM_SET_BY_USER &&
1463                           last_request->intersect)
1464                         return -EOPNOTSUPP;
1465                 /*
1466                  * Process user requests only after previous user/driver/core
1467                  * requests have been processed
1468                  */
1469                 if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE ||
1470                     last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER ||
1471                     last_request->initiator == NL80211_REGDOM_SET_BY_USER) {
1472                         if (regdom_changes(last_request->alpha2))
1473                                 return -EAGAIN;
1474                 }
1475
1476                 if (!is_old_static_regdom(cfg80211_regdomain) &&
1477                     !regdom_changes(pending_request->alpha2))
1478                         return -EALREADY;
1479
1480                 return 0;
1481         }
1482
1483         return -EINVAL;
1484 }
1485
1486 /**
1487  * __regulatory_hint - hint to the wireless core a regulatory domain
1488  * @wiphy: if the hint comes from country information from an AP, this
1489  *      is required to be set to the wiphy that received the information
1490  * @pending_request: the regulatory request currently being processed
1491  *
1492  * The Wireless subsystem can use this function to hint to the wireless core
1493  * what it believes should be the current regulatory domain.
1494  *
1495  * Returns zero if all went fine, %-EALREADY if a regulatory domain had
1496  * already been set or other standard error codes.
1497  *
1498  * Caller must hold &cfg80211_mutex
1499  */
1500 static int __regulatory_hint(struct wiphy *wiphy,
1501                              struct regulatory_request *pending_request)
1502 {
1503         bool intersect = false;
1504         int r = 0;
1505
1506         assert_cfg80211_lock();
1507
1508         r = ignore_request(wiphy, pending_request);
1509
1510         if (r == REG_INTERSECT) {
1511                 if (pending_request->initiator ==
1512                     NL80211_REGDOM_SET_BY_DRIVER) {
1513                         r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1514                         if (r) {
1515                                 kfree(pending_request);
1516                                 return r;
1517                         }
1518                 }
1519                 intersect = true;
1520         } else if (r) {
1521                 /*
1522                  * If the regulatory domain being requested by the
1523                  * driver has already been set just copy it to the
1524                  * wiphy
1525                  */
1526                 if (r == -EALREADY &&
1527                     pending_request->initiator ==
1528                     NL80211_REGDOM_SET_BY_DRIVER) {
1529                         r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1530                         if (r) {
1531                                 kfree(pending_request);
1532                                 return r;
1533                         }
1534                         r = -EALREADY;
1535                         goto new_request;
1536                 }
1537                 kfree(pending_request);
1538                 return r;
1539         }
1540
1541 new_request:
1542         kfree(last_request);
1543
1544         last_request = pending_request;
1545         last_request->intersect = intersect;
1546
1547         pending_request = NULL;
1548
1549         /* When r == REG_INTERSECT we do need to call CRDA */
1550         if (r < 0) {
1551                 /*
1552                  * Since CRDA will not be called in this case as we already
1553                  * have applied the requested regulatory domain before we just
1554                  * inform userspace we have processed the request
1555                  */
1556                 if (r == -EALREADY)
1557                         nl80211_send_reg_change_event(last_request);
1558                 return r;
1559         }
1560
1561         return call_crda(last_request->alpha2);
1562 }
1563
1564 /* This processes *all* regulatory hints */
1565 static void reg_process_hint(struct regulatory_request *reg_request)
1566 {
1567         int r = 0;
1568         struct wiphy *wiphy = NULL;
1569
1570         BUG_ON(!reg_request->alpha2);
1571
1572         mutex_lock(&cfg80211_mutex);
1573
1574         if (wiphy_idx_valid(reg_request->wiphy_idx))
1575                 wiphy = wiphy_idx_to_wiphy(reg_request->wiphy_idx);
1576
1577         if (reg_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1578             !wiphy) {
1579                 kfree(reg_request);
1580                 goto out;
1581         }
1582
1583         r = __regulatory_hint(wiphy, reg_request);
1584         /* This is required so that the orig_* parameters are saved */
1585         if (r == -EALREADY && wiphy && wiphy->strict_regulatory)
1586                 wiphy_update_regulatory(wiphy, reg_request->initiator);
1587 out:
1588         mutex_unlock(&cfg80211_mutex);
1589 }
1590
1591 /* Processes regulatory hints, this is all the NL80211_REGDOM_SET_BY_* */
1592 static void reg_process_pending_hints(void)
1593         {
1594         struct regulatory_request *reg_request;
1595
1596         spin_lock(&reg_requests_lock);
1597         while (!list_empty(&reg_requests_list)) {
1598                 reg_request = list_first_entry(&reg_requests_list,
1599                                                struct regulatory_request,
1600                                                list);
1601                 list_del_init(&reg_request->list);
1602
1603                 spin_unlock(&reg_requests_lock);
1604                 reg_process_hint(reg_request);
1605                 spin_lock(&reg_requests_lock);
1606         }
1607         spin_unlock(&reg_requests_lock);
1608 }
1609
1610 /* Processes beacon hints -- this has nothing to do with country IEs */
1611 static void reg_process_pending_beacon_hints(void)
1612 {
1613         struct cfg80211_registered_device *rdev;
1614         struct reg_beacon *pending_beacon, *tmp;
1615
1616         mutex_lock(&cfg80211_mutex);
1617
1618         /* This goes through the _pending_ beacon list */
1619         spin_lock_bh(&reg_pending_beacons_lock);
1620
1621         if (list_empty(&reg_pending_beacons)) {
1622                 spin_unlock_bh(&reg_pending_beacons_lock);
1623                 goto out;
1624         }
1625
1626         list_for_each_entry_safe(pending_beacon, tmp,
1627                                  &reg_pending_beacons, list) {
1628
1629                 list_del_init(&pending_beacon->list);
1630
1631                 /* Applies the beacon hint to current wiphys */
1632                 list_for_each_entry(rdev, &cfg80211_rdev_list, list)
1633                         wiphy_update_new_beacon(&rdev->wiphy, pending_beacon);
1634
1635                 /* Remembers the beacon hint for new wiphys or reg changes */
1636                 list_add_tail(&pending_beacon->list, &reg_beacon_list);
1637         }
1638
1639         spin_unlock_bh(&reg_pending_beacons_lock);
1640 out:
1641         mutex_unlock(&cfg80211_mutex);
1642 }
1643
1644 static void reg_todo(struct work_struct *work)
1645 {
1646         reg_process_pending_hints();
1647         reg_process_pending_beacon_hints();
1648 }
1649
1650 static DECLARE_WORK(reg_work, reg_todo);
1651
1652 static void queue_regulatory_request(struct regulatory_request *request)
1653 {
1654         spin_lock(&reg_requests_lock);
1655         list_add_tail(&request->list, &reg_requests_list);
1656         spin_unlock(&reg_requests_lock);
1657
1658         schedule_work(&reg_work);
1659 }
1660
1661 /* Core regulatory hint -- happens once during cfg80211_init() */
1662 static int regulatory_hint_core(const char *alpha2)
1663 {
1664         struct regulatory_request *request;
1665
1666         BUG_ON(last_request);
1667
1668         request = kzalloc(sizeof(struct regulatory_request),
1669                           GFP_KERNEL);
1670         if (!request)
1671                 return -ENOMEM;
1672
1673         request->alpha2[0] = alpha2[0];
1674         request->alpha2[1] = alpha2[1];
1675         request->initiator = NL80211_REGDOM_SET_BY_CORE;
1676
1677         queue_regulatory_request(request);
1678
1679         /*
1680          * This ensures last_request is populated once modules
1681          * come swinging in and calling regulatory hints and
1682          * wiphy_apply_custom_regulatory().
1683          */
1684         flush_scheduled_work();
1685
1686         return 0;
1687 }
1688
1689 /* User hints */
1690 int regulatory_hint_user(const char *alpha2)
1691 {
1692         struct regulatory_request *request;
1693
1694         BUG_ON(!alpha2);
1695
1696         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1697         if (!request)
1698                 return -ENOMEM;
1699
1700         request->wiphy_idx = WIPHY_IDX_STALE;
1701         request->alpha2[0] = alpha2[0];
1702         request->alpha2[1] = alpha2[1];
1703         request->initiator = NL80211_REGDOM_SET_BY_USER,
1704
1705         queue_regulatory_request(request);
1706
1707         return 0;
1708 }
1709
1710 /* Driver hints */
1711 int regulatory_hint(struct wiphy *wiphy, const char *alpha2)
1712 {
1713         struct regulatory_request *request;
1714
1715         BUG_ON(!alpha2);
1716         BUG_ON(!wiphy);
1717
1718         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1719         if (!request)
1720                 return -ENOMEM;
1721
1722         request->wiphy_idx = get_wiphy_idx(wiphy);
1723
1724         /* Must have registered wiphy first */
1725         BUG_ON(!wiphy_idx_valid(request->wiphy_idx));
1726
1727         request->alpha2[0] = alpha2[0];
1728         request->alpha2[1] = alpha2[1];
1729         request->initiator = NL80211_REGDOM_SET_BY_DRIVER;
1730
1731         queue_regulatory_request(request);
1732
1733         return 0;
1734 }
1735 EXPORT_SYMBOL(regulatory_hint);
1736
1737 static bool reg_same_country_ie_hint(struct wiphy *wiphy,
1738                         u32 country_ie_checksum)
1739 {
1740         struct wiphy *request_wiphy;
1741
1742         assert_cfg80211_lock();
1743
1744         if (unlikely(last_request->initiator !=
1745             NL80211_REGDOM_SET_BY_COUNTRY_IE))
1746                 return false;
1747
1748         request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
1749
1750         if (!request_wiphy)
1751                 return false;
1752
1753         if (likely(request_wiphy != wiphy))
1754                 return !country_ie_integrity_changes(country_ie_checksum);
1755         /*
1756          * We should not have let these through at this point, they
1757          * should have been picked up earlier by the first alpha2 check
1758          * on the device
1759          */
1760         if (WARN_ON(!country_ie_integrity_changes(country_ie_checksum)))
1761                 return true;
1762         return false;
1763 }
1764
1765 /*
1766  * We hold wdev_lock() here so we cannot hold cfg80211_mutex() and
1767  * therefore cannot iterate over the rdev list here.
1768  */
1769 void regulatory_hint_11d(struct wiphy *wiphy,
1770                         u8 *country_ie,
1771                         u8 country_ie_len)
1772 {
1773         struct ieee80211_regdomain *rd = NULL;
1774         char alpha2[2];
1775         u32 checksum = 0;
1776         enum environment_cap env = ENVIRON_ANY;
1777         struct regulatory_request *request;
1778
1779         mutex_lock(&cfg80211_mutex);
1780
1781         if (unlikely(!last_request))
1782                 goto out;
1783
1784         /* IE len must be evenly divisible by 2 */
1785         if (country_ie_len & 0x01)
1786                 goto out;
1787
1788         if (country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN)
1789                 goto out;
1790
1791         /*
1792          * Pending country IE processing, this can happen after we
1793          * call CRDA and wait for a response if a beacon was received before
1794          * we were able to process the last regulatory_hint_11d() call
1795          */
1796         if (country_ie_regdomain)
1797                 goto out;
1798
1799         alpha2[0] = country_ie[0];
1800         alpha2[1] = country_ie[1];
1801
1802         if (country_ie[2] == 'I')
1803                 env = ENVIRON_INDOOR;
1804         else if (country_ie[2] == 'O')
1805                 env = ENVIRON_OUTDOOR;
1806
1807         /*
1808          * We will run this for *every* beacon processed for the BSSID, so
1809          * we optimize an early check to exit out early if we don't have to
1810          * do anything
1811          *
1812          * We leave conflict resolution to the workqueue, where can hold
1813          * cfg80211_mutex.
1814          */
1815         if (likely(last_request->initiator ==
1816             NL80211_REGDOM_SET_BY_COUNTRY_IE &&
1817             wiphy_idx_valid(last_request->wiphy_idx)))
1818                 goto out;
1819
1820         rd = country_ie_2_rd(country_ie, country_ie_len, &checksum);
1821         if (!rd)
1822                 goto out;
1823
1824         /*
1825          * This will not happen right now but we leave it here for the
1826          * the future when we want to add suspend/resume support and having
1827          * the user move to another country after doing so, or having the user
1828          * move to another AP. Right now we just trust the first AP.
1829          *
1830          * If we hit this before we add this support we want to be informed of
1831          * it as it would indicate a mistake in the current design
1832          */
1833         if (WARN_ON(reg_same_country_ie_hint(wiphy, checksum)))
1834                 goto free_rd_out;
1835
1836         request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
1837         if (!request)
1838                 goto free_rd_out;
1839
1840         /*
1841          * We keep this around for when CRDA comes back with a response so
1842          * we can intersect with that
1843          */
1844         country_ie_regdomain = rd;
1845
1846         request->wiphy_idx = get_wiphy_idx(wiphy);
1847         request->alpha2[0] = rd->alpha2[0];
1848         request->alpha2[1] = rd->alpha2[1];
1849         request->initiator = NL80211_REGDOM_SET_BY_COUNTRY_IE;
1850         request->country_ie_checksum = checksum;
1851         request->country_ie_env = env;
1852
1853         mutex_unlock(&cfg80211_mutex);
1854
1855         queue_regulatory_request(request);
1856
1857         return;
1858
1859 free_rd_out:
1860         kfree(rd);
1861 out:
1862         mutex_unlock(&cfg80211_mutex);
1863 }
1864 EXPORT_SYMBOL(regulatory_hint_11d);
1865
1866 static bool freq_is_chan_12_13_14(u16 freq)
1867 {
1868         if (freq == ieee80211_channel_to_frequency(12) ||
1869             freq == ieee80211_channel_to_frequency(13) ||
1870             freq == ieee80211_channel_to_frequency(14))
1871                 return true;
1872         return false;
1873 }
1874
1875 int regulatory_hint_found_beacon(struct wiphy *wiphy,
1876                                  struct ieee80211_channel *beacon_chan,
1877                                  gfp_t gfp)
1878 {
1879         struct reg_beacon *reg_beacon;
1880
1881         if (likely((beacon_chan->beacon_found ||
1882             (beacon_chan->flags & IEEE80211_CHAN_RADAR) ||
1883             (beacon_chan->band == IEEE80211_BAND_2GHZ &&
1884              !freq_is_chan_12_13_14(beacon_chan->center_freq)))))
1885                 return 0;
1886
1887         reg_beacon = kzalloc(sizeof(struct reg_beacon), gfp);
1888         if (!reg_beacon)
1889                 return -ENOMEM;
1890
1891 #ifdef CONFIG_CFG80211_REG_DEBUG
1892         printk(KERN_DEBUG "cfg80211: Found new beacon on "
1893                 "frequency: %d MHz (Ch %d) on %s\n",
1894                 beacon_chan->center_freq,
1895                 ieee80211_frequency_to_channel(beacon_chan->center_freq),
1896                 wiphy_name(wiphy));
1897 #endif
1898         memcpy(&reg_beacon->chan, beacon_chan,
1899                 sizeof(struct ieee80211_channel));
1900
1901
1902         /*
1903          * Since we can be called from BH or and non-BH context
1904          * we must use spin_lock_bh()
1905          */
1906         spin_lock_bh(&reg_pending_beacons_lock);
1907         list_add_tail(&reg_beacon->list, &reg_pending_beacons);
1908         spin_unlock_bh(&reg_pending_beacons_lock);
1909
1910         schedule_work(&reg_work);
1911
1912         return 0;
1913 }
1914
1915 static void print_rd_rules(const struct ieee80211_regdomain *rd)
1916 {
1917         unsigned int i;
1918         const struct ieee80211_reg_rule *reg_rule = NULL;
1919         const struct ieee80211_freq_range *freq_range = NULL;
1920         const struct ieee80211_power_rule *power_rule = NULL;
1921
1922         printk(KERN_INFO "\t(start_freq - end_freq @ bandwidth), "
1923                 "(max_antenna_gain, max_eirp)\n");
1924
1925         for (i = 0; i < rd->n_reg_rules; i++) {
1926                 reg_rule = &rd->reg_rules[i];
1927                 freq_range = &reg_rule->freq_range;
1928                 power_rule = &reg_rule->power_rule;
1929
1930                 /*
1931                  * There may not be documentation for max antenna gain
1932                  * in certain regions
1933                  */
1934                 if (power_rule->max_antenna_gain)
1935                         printk(KERN_INFO "\t(%d KHz - %d KHz @ %d KHz), "
1936                                 "(%d mBi, %d mBm)\n",
1937                                 freq_range->start_freq_khz,
1938                                 freq_range->end_freq_khz,
1939                                 freq_range->max_bandwidth_khz,
1940                                 power_rule->max_antenna_gain,
1941                                 power_rule->max_eirp);
1942                 else
1943                         printk(KERN_INFO "\t(%d KHz - %d KHz @ %d KHz), "
1944                                 "(N/A, %d mBm)\n",
1945                                 freq_range->start_freq_khz,
1946                                 freq_range->end_freq_khz,
1947                                 freq_range->max_bandwidth_khz,
1948                                 power_rule->max_eirp);
1949         }
1950 }
1951
1952 static void print_regdomain(const struct ieee80211_regdomain *rd)
1953 {
1954
1955         if (is_intersected_alpha2(rd->alpha2)) {
1956
1957                 if (last_request->initiator ==
1958                     NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1959                         struct cfg80211_registered_device *rdev;
1960                         rdev = cfg80211_rdev_by_wiphy_idx(
1961                                 last_request->wiphy_idx);
1962                         if (rdev) {
1963                                 printk(KERN_INFO "cfg80211: Current regulatory "
1964                                         "domain updated by AP to: %c%c\n",
1965                                         rdev->country_ie_alpha2[0],
1966                                         rdev->country_ie_alpha2[1]);
1967                         } else
1968                                 printk(KERN_INFO "cfg80211: Current regulatory "
1969                                         "domain intersected: \n");
1970                 } else
1971                                 printk(KERN_INFO "cfg80211: Current regulatory "
1972                                         "domain intersected: \n");
1973         } else if (is_world_regdom(rd->alpha2))
1974                 printk(KERN_INFO "cfg80211: World regulatory "
1975                         "domain updated:\n");
1976         else {
1977                 if (is_unknown_alpha2(rd->alpha2))
1978                         printk(KERN_INFO "cfg80211: Regulatory domain "
1979                                 "changed to driver built-in settings "
1980                                 "(unknown country)\n");
1981                 else
1982                         printk(KERN_INFO "cfg80211: Regulatory domain "
1983                                 "changed to country: %c%c\n",
1984                                 rd->alpha2[0], rd->alpha2[1]);
1985         }
1986         print_rd_rules(rd);
1987 }
1988
1989 static void print_regdomain_info(const struct ieee80211_regdomain *rd)
1990 {
1991         printk(KERN_INFO "cfg80211: Regulatory domain: %c%c\n",
1992                 rd->alpha2[0], rd->alpha2[1]);
1993         print_rd_rules(rd);
1994 }
1995
1996 #ifdef CONFIG_CFG80211_REG_DEBUG
1997 static void reg_country_ie_process_debug(
1998         const struct ieee80211_regdomain *rd,
1999         const struct ieee80211_regdomain *country_ie_regdomain,
2000         const struct ieee80211_regdomain *intersected_rd)
2001 {
2002         printk(KERN_DEBUG "cfg80211: Received country IE:\n");
2003         print_regdomain_info(country_ie_regdomain);
2004         printk(KERN_DEBUG "cfg80211: CRDA thinks this should applied:\n");
2005         print_regdomain_info(rd);
2006         if (intersected_rd) {
2007                 printk(KERN_DEBUG "cfg80211: We intersect both of these "
2008                         "and get:\n");
2009                 print_regdomain_info(intersected_rd);
2010                 return;
2011         }
2012         printk(KERN_DEBUG "cfg80211: Intersection between both failed\n");
2013 }
2014 #else
2015 static inline void reg_country_ie_process_debug(
2016         const struct ieee80211_regdomain *rd,
2017         const struct ieee80211_regdomain *country_ie_regdomain,
2018         const struct ieee80211_regdomain *intersected_rd)
2019 {
2020 }
2021 #endif
2022
2023 /* Takes ownership of rd only if it doesn't fail */
2024 static int __set_regdom(const struct ieee80211_regdomain *rd)
2025 {
2026         const struct ieee80211_regdomain *intersected_rd = NULL;
2027         struct cfg80211_registered_device *rdev = NULL;
2028         struct wiphy *request_wiphy;
2029         /* Some basic sanity checks first */
2030
2031         if (is_world_regdom(rd->alpha2)) {
2032                 if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
2033                         return -EINVAL;
2034                 update_world_regdomain(rd);
2035                 return 0;
2036         }
2037
2038         if (!is_alpha2_set(rd->alpha2) && !is_an_alpha2(rd->alpha2) &&
2039                         !is_unknown_alpha2(rd->alpha2))
2040                 return -EINVAL;
2041
2042         if (!last_request)
2043                 return -EINVAL;
2044
2045         /*
2046          * Lets only bother proceeding on the same alpha2 if the current
2047          * rd is non static (it means CRDA was present and was used last)
2048          * and the pending request came in from a country IE
2049          */
2050         if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2051                 /*
2052                  * If someone else asked us to change the rd lets only bother
2053                  * checking if the alpha2 changes if CRDA was already called
2054                  */
2055                 if (!is_old_static_regdom(cfg80211_regdomain) &&
2056                     !regdom_changes(rd->alpha2))
2057                         return -EINVAL;
2058         }
2059
2060         /*
2061          * Now lets set the regulatory domain, update all driver channels
2062          * and finally inform them of what we have done, in case they want
2063          * to review or adjust their own settings based on their own
2064          * internal EEPROM data
2065          */
2066
2067         if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
2068                 return -EINVAL;
2069
2070         if (!is_valid_rd(rd)) {
2071                 printk(KERN_ERR "cfg80211: Invalid "
2072                         "regulatory domain detected:\n");
2073                 print_regdomain_info(rd);
2074                 return -EINVAL;
2075         }
2076
2077         request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
2078
2079         if (!last_request->intersect) {
2080                 int r;
2081
2082                 if (last_request->initiator != NL80211_REGDOM_SET_BY_DRIVER) {
2083                         reset_regdomains();
2084                         cfg80211_regdomain = rd;
2085                         return 0;
2086                 }
2087
2088                 /*
2089                  * For a driver hint, lets copy the regulatory domain the
2090                  * driver wanted to the wiphy to deal with conflicts
2091                  */
2092
2093                 /*
2094                  * Userspace could have sent two replies with only
2095                  * one kernel request.
2096                  */
2097                 if (request_wiphy->regd)
2098                         return -EALREADY;
2099
2100                 r = reg_copy_regd(&request_wiphy->regd, rd);
2101                 if (r)
2102                         return r;
2103
2104                 reset_regdomains();
2105                 cfg80211_regdomain = rd;
2106                 return 0;
2107         }
2108
2109         /* Intersection requires a bit more work */
2110
2111         if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2112
2113                 intersected_rd = regdom_intersect(rd, cfg80211_regdomain);
2114                 if (!intersected_rd)
2115                         return -EINVAL;
2116
2117                 /*
2118                  * We can trash what CRDA provided now.
2119                  * However if a driver requested this specific regulatory
2120                  * domain we keep it for its private use
2121                  */
2122                 if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER)
2123                         request_wiphy->regd = rd;
2124                 else
2125                         kfree(rd);
2126
2127                 rd = NULL;
2128
2129                 reset_regdomains();
2130                 cfg80211_regdomain = intersected_rd;
2131
2132                 return 0;
2133         }
2134
2135         /*
2136          * Country IE requests are handled a bit differently, we intersect
2137          * the country IE rd with what CRDA believes that country should have
2138          */
2139
2140         /*
2141          * Userspace could have sent two replies with only
2142          * one kernel request. By the second reply we would have
2143          * already processed and consumed the country_ie_regdomain.
2144          */
2145         if (!country_ie_regdomain)
2146                 return -EALREADY;
2147         BUG_ON(rd == country_ie_regdomain);
2148
2149         /*
2150          * Intersect what CRDA returned and our what we
2151          * had built from the Country IE received
2152          */
2153
2154         intersected_rd = regdom_intersect(rd, country_ie_regdomain);
2155
2156         reg_country_ie_process_debug(rd,
2157                                      country_ie_regdomain,
2158                                      intersected_rd);
2159
2160         kfree(country_ie_regdomain);
2161         country_ie_regdomain = NULL;
2162
2163         if (!intersected_rd)
2164                 return -EINVAL;
2165
2166         rdev = wiphy_to_dev(request_wiphy);
2167
2168         rdev->country_ie_alpha2[0] = rd->alpha2[0];
2169         rdev->country_ie_alpha2[1] = rd->alpha2[1];
2170         rdev->env = last_request->country_ie_env;
2171
2172         BUG_ON(intersected_rd == rd);
2173
2174         kfree(rd);
2175         rd = NULL;
2176
2177         reset_regdomains();
2178         cfg80211_regdomain = intersected_rd;
2179
2180         return 0;
2181 }
2182
2183
2184 /*
2185  * Use this call to set the current regulatory domain. Conflicts with
2186  * multiple drivers can be ironed out later. Caller must've already
2187  * kmalloc'd the rd structure. Caller must hold cfg80211_mutex
2188  */
2189 int set_regdom(const struct ieee80211_regdomain *rd)
2190 {
2191         int r;
2192
2193         assert_cfg80211_lock();
2194
2195         /* Note that this doesn't update the wiphys, this is done below */
2196         r = __set_regdom(rd);
2197         if (r) {
2198                 kfree(rd);
2199                 return r;
2200         }
2201
2202         /* This would make this whole thing pointless */
2203         if (!last_request->intersect)
2204                 BUG_ON(rd != cfg80211_regdomain);
2205
2206         /* update all wiphys now with the new established regulatory domain */
2207         update_all_wiphy_regulatory(last_request->initiator);
2208
2209         print_regdomain(cfg80211_regdomain);
2210
2211         nl80211_send_reg_change_event(last_request);
2212
2213         return r;
2214 }
2215
2216 /* Caller must hold cfg80211_mutex */
2217 void reg_device_remove(struct wiphy *wiphy)
2218 {
2219         struct wiphy *request_wiphy = NULL;
2220
2221         assert_cfg80211_lock();
2222
2223         kfree(wiphy->regd);
2224
2225         if (last_request)
2226                 request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
2227
2228         if (!request_wiphy || request_wiphy != wiphy)
2229                 return;
2230
2231         last_request->wiphy_idx = WIPHY_IDX_STALE;
2232         last_request->country_ie_env = ENVIRON_ANY;
2233 }
2234
2235 int regulatory_init(void)
2236 {
2237         int err = 0;
2238
2239         reg_pdev = platform_device_register_simple("regulatory", 0, NULL, 0);
2240         if (IS_ERR(reg_pdev))
2241                 return PTR_ERR(reg_pdev);
2242
2243         spin_lock_init(&reg_requests_lock);
2244         spin_lock_init(&reg_pending_beacons_lock);
2245
2246 #ifdef CONFIG_WIRELESS_OLD_REGULATORY
2247         cfg80211_regdomain = static_regdom(ieee80211_regdom);
2248
2249         printk(KERN_INFO "cfg80211: Using static regulatory domain info\n");
2250         print_regdomain_info(cfg80211_regdomain);
2251 #else
2252         cfg80211_regdomain = cfg80211_world_regdom;
2253
2254 #endif
2255         /* We always try to get an update for the static regdomain */
2256         err = regulatory_hint_core(cfg80211_regdomain->alpha2);
2257         if (err) {
2258                 if (err == -ENOMEM)
2259                         return err;
2260                 /*
2261                  * N.B. kobject_uevent_env() can fail mainly for when we're out
2262                  * memory which is handled and propagated appropriately above
2263                  * but it can also fail during a netlink_broadcast() or during
2264                  * early boot for call_usermodehelper(). For now treat these
2265                  * errors as non-fatal.
2266                  */
2267                 printk(KERN_ERR "cfg80211: kobject_uevent_env() was unable "
2268                         "to call CRDA during init");
2269 #ifdef CONFIG_CFG80211_REG_DEBUG
2270                 /* We want to find out exactly why when debugging */
2271                 WARN_ON(err);
2272 #endif
2273         }
2274
2275         /*
2276          * Finally, if the user set the module parameter treat it
2277          * as a user hint.
2278          */
2279         if (!is_world_regdom(ieee80211_regdom))
2280                 regulatory_hint_user(ieee80211_regdom);
2281
2282         return 0;
2283 }
2284
2285 void regulatory_exit(void)
2286 {
2287         struct regulatory_request *reg_request, *tmp;
2288         struct reg_beacon *reg_beacon, *btmp;
2289
2290         cancel_work_sync(&reg_work);
2291
2292         mutex_lock(&cfg80211_mutex);
2293
2294         reset_regdomains();
2295
2296         kfree(country_ie_regdomain);
2297         country_ie_regdomain = NULL;
2298
2299         kfree(last_request);
2300
2301         platform_device_unregister(reg_pdev);
2302
2303         spin_lock_bh(&reg_pending_beacons_lock);
2304         if (!list_empty(&reg_pending_beacons)) {
2305                 list_for_each_entry_safe(reg_beacon, btmp,
2306                                          &reg_pending_beacons, list) {
2307                         list_del(&reg_beacon->list);
2308                         kfree(reg_beacon);
2309                 }
2310         }
2311         spin_unlock_bh(&reg_pending_beacons_lock);
2312
2313         if (!list_empty(&reg_beacon_list)) {
2314                 list_for_each_entry_safe(reg_beacon, btmp,
2315                                          &reg_beacon_list, list) {
2316                         list_del(&reg_beacon->list);
2317                         kfree(reg_beacon);
2318                 }
2319         }
2320
2321         spin_lock(&reg_requests_lock);
2322         if (!list_empty(&reg_requests_list)) {
2323                 list_for_each_entry_safe(reg_request, tmp,
2324                                          &reg_requests_list, list) {
2325                         list_del(&reg_request->list);
2326                         kfree(reg_request);
2327                 }
2328         }
2329         spin_unlock(&reg_requests_lock);
2330
2331         mutex_unlock(&cfg80211_mutex);
2332 }