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>
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.
13 * DOC: Wireless regulatory infrastructure
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.
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.
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.
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.
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>
46 * wiphy is set if this request's initiator is
47 * REGDOM_SET_BY_COUNTRY_IE or _DRIVER
49 struct regulatory_request {
51 enum reg_set_by initiator;
55 static struct regulatory_request *last_request;
57 /* To trigger userspace events */
58 static struct platform_device *reg_pdev;
60 /* Keep the ordering from large to small */
61 static u32 supported_bandwidths[] = {
66 /* Central wireless core regulatory domains, we only need two,
67 * the current one and a world regulatory domain in case we have no
68 * information to give us an alpha2 */
69 static const struct ieee80211_regdomain *cfg80211_regdomain;
71 /* We keep a static world regulatory domain in case of the absence of CRDA */
72 static const struct ieee80211_regdomain world_regdom = {
76 REG_RULE(2412-10, 2462+10, 40, 6, 20,
77 NL80211_RRF_PASSIVE_SCAN |
82 static const struct ieee80211_regdomain *cfg80211_world_regdom =
85 #ifdef CONFIG_WIRELESS_OLD_REGULATORY
86 static char *ieee80211_regdom = "US";
87 module_param(ieee80211_regdom, charp, 0444);
88 MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain code");
90 /* We assume 40 MHz bandwidth for the old regulatory work.
91 * We make emphasis we are using the exact same frequencies
94 static const struct ieee80211_regdomain us_regdom = {
98 /* IEEE 802.11b/g, channels 1..11 */
99 REG_RULE(2412-10, 2462+10, 40, 6, 27, 0),
100 /* IEEE 802.11a, channel 36 */
101 REG_RULE(5180-10, 5180+10, 40, 6, 23, 0),
102 /* IEEE 802.11a, channel 40 */
103 REG_RULE(5200-10, 5200+10, 40, 6, 23, 0),
104 /* IEEE 802.11a, channel 44 */
105 REG_RULE(5220-10, 5220+10, 40, 6, 23, 0),
106 /* IEEE 802.11a, channels 48..64 */
107 REG_RULE(5240-10, 5320+10, 40, 6, 23, 0),
108 /* IEEE 802.11a, channels 149..165, outdoor */
109 REG_RULE(5745-10, 5825+10, 40, 6, 30, 0),
113 static const struct ieee80211_regdomain jp_regdom = {
117 /* IEEE 802.11b/g, channels 1..14 */
118 REG_RULE(2412-10, 2484+10, 40, 6, 20, 0),
119 /* IEEE 802.11a, channels 34..48 */
120 REG_RULE(5170-10, 5240+10, 40, 6, 20,
121 NL80211_RRF_PASSIVE_SCAN),
122 /* IEEE 802.11a, channels 52..64 */
123 REG_RULE(5260-10, 5320+10, 40, 6, 20,
124 NL80211_RRF_NO_IBSS |
129 static const struct ieee80211_regdomain eu_regdom = {
131 /* This alpha2 is bogus, we leave it here just for stupid
132 * backward compatibility */
135 /* IEEE 802.11b/g, channels 1..13 */
136 REG_RULE(2412-10, 2472+10, 40, 6, 20, 0),
137 /* IEEE 802.11a, channel 36 */
138 REG_RULE(5180-10, 5180+10, 40, 6, 23,
139 NL80211_RRF_PASSIVE_SCAN),
140 /* IEEE 802.11a, channel 40 */
141 REG_RULE(5200-10, 5200+10, 40, 6, 23,
142 NL80211_RRF_PASSIVE_SCAN),
143 /* IEEE 802.11a, channel 44 */
144 REG_RULE(5220-10, 5220+10, 40, 6, 23,
145 NL80211_RRF_PASSIVE_SCAN),
146 /* IEEE 802.11a, channels 48..64 */
147 REG_RULE(5240-10, 5320+10, 40, 6, 20,
148 NL80211_RRF_NO_IBSS |
150 /* IEEE 802.11a, channels 100..140 */
151 REG_RULE(5500-10, 5700+10, 40, 6, 30,
152 NL80211_RRF_NO_IBSS |
157 static const struct ieee80211_regdomain *static_regdom(char *alpha2)
159 if (alpha2[0] == 'U' && alpha2[1] == 'S')
161 if (alpha2[0] == 'J' && alpha2[1] == 'P')
163 if (alpha2[0] == 'E' && alpha2[1] == 'U')
165 /* Default, as per the old rules */
169 static bool is_old_static_regdom(const struct ieee80211_regdomain *rd)
171 if (rd == &us_regdom || rd == &jp_regdom || rd == &eu_regdom)
176 static inline bool is_old_static_regdom(const struct ieee80211_regdomain *rd)
182 static void reset_regdomains(void)
184 /* avoid freeing static information or freeing something twice */
185 if (cfg80211_regdomain == cfg80211_world_regdom)
186 cfg80211_regdomain = NULL;
187 if (cfg80211_world_regdom == &world_regdom)
188 cfg80211_world_regdom = NULL;
189 if (cfg80211_regdomain == &world_regdom)
190 cfg80211_regdomain = NULL;
191 if (is_old_static_regdom(cfg80211_regdomain))
192 cfg80211_regdomain = NULL;
194 kfree(cfg80211_regdomain);
195 kfree(cfg80211_world_regdom);
197 cfg80211_world_regdom = &world_regdom;
198 cfg80211_regdomain = NULL;
201 /* Dynamic world regulatory domain requested by the wireless
202 * core upon initialization */
203 static void update_world_regdomain(const struct ieee80211_regdomain *rd)
205 BUG_ON(!last_request);
209 cfg80211_world_regdom = rd;
210 cfg80211_regdomain = rd;
213 bool is_world_regdom(const char *alpha2)
217 if (alpha2[0] == '0' && alpha2[1] == '0')
222 static bool is_alpha2_set(const char *alpha2)
226 if (alpha2[0] != 0 && alpha2[1] != 0)
231 static bool is_alpha_upper(char letter)
234 if (letter >= 65 && letter <= 90)
239 static bool is_unknown_alpha2(const char *alpha2)
243 /* Special case where regulatory domain was built by driver
244 * but a specific alpha2 cannot be determined */
245 if (alpha2[0] == '9' && alpha2[1] == '9')
250 static bool is_an_alpha2(const char *alpha2)
254 if (is_alpha_upper(alpha2[0]) && is_alpha_upper(alpha2[1]))
259 static bool alpha2_equal(const char *alpha2_x, const char *alpha2_y)
261 if (!alpha2_x || !alpha2_y)
263 if (alpha2_x[0] == alpha2_y[0] &&
264 alpha2_x[1] == alpha2_y[1])
269 static bool regdom_changed(const char *alpha2)
271 if (!cfg80211_regdomain)
273 if (alpha2_equal(cfg80211_regdomain->alpha2, alpha2))
278 /* This lets us keep regulatory code which is updated on a regulatory
279 * basis in userspace. */
280 static int call_crda(const char *alpha2)
282 char country_env[9 + 2] = "COUNTRY=";
288 if (!is_world_regdom((char *) alpha2))
289 printk(KERN_INFO "cfg80211: Calling CRDA for country: %c%c\n",
290 alpha2[0], alpha2[1]);
292 printk(KERN_INFO "cfg80211: Calling CRDA to update world "
293 "regulatory domain\n");
295 country_env[8] = alpha2[0];
296 country_env[9] = alpha2[1];
298 return kobject_uevent_env(®_pdev->dev.kobj, KOBJ_CHANGE, envp);
301 /* This has the logic which determines when a new request
302 * should be ignored. */
303 static int ignore_request(struct wiphy *wiphy, enum reg_set_by set_by,
306 /* All initial requests are respected */
311 case REGDOM_SET_BY_INIT:
313 case REGDOM_SET_BY_CORE:
314 /* Always respect new wireless core hints, should only
315 * come in for updating the world regulatory domain at init
318 case REGDOM_SET_BY_COUNTRY_IE:
319 if (last_request->initiator == REGDOM_SET_BY_COUNTRY_IE) {
320 if (last_request->wiphy != wiphy) {
321 /* Two cards with two APs claiming different
322 * different Country IE alpha2s!
323 * You're special!! */
324 if (!alpha2_equal(last_request->alpha2,
325 cfg80211_regdomain->alpha2)) {
326 /* XXX: Deal with conflict, consider
327 * building a new one out of the
334 /* Two consecutive Country IE hints on the same wiphy */
335 if (!alpha2_equal(cfg80211_regdomain->alpha2, alpha2))
339 if (WARN_ON(!is_alpha2_set(alpha2) || !is_an_alpha2(alpha2)),
340 "Invalid Country IE regulatory hint passed "
341 "to the wireless core\n")
343 /* We ignore Country IE hints for now, as we haven't yet
344 * added the dot11MultiDomainCapabilityEnabled flag
347 case REGDOM_SET_BY_DRIVER:
349 if (last_request->initiator == REGDOM_SET_BY_DRIVER)
351 if (last_request->initiator == REGDOM_SET_BY_CORE)
353 /* XXX: Handle intersection, and add the
354 * dot11MultiDomainCapabilityEnabled flag to wiphy. For now
355 * we assume the driver has this set to false, following the
356 * 802.11d dot11MultiDomainCapabilityEnabled documentation */
357 if (last_request->initiator == REGDOM_SET_BY_COUNTRY_IE)
360 case REGDOM_SET_BY_USER:
361 if (last_request->initiator == REGDOM_SET_BY_USER ||
362 last_request->initiator == REGDOM_SET_BY_CORE)
364 /* Drivers can use their wiphy's reg_notifier()
365 * to override any information */
366 if (last_request->initiator == REGDOM_SET_BY_DRIVER)
368 /* XXX: Handle intersection */
369 if (last_request->initiator == REGDOM_SET_BY_COUNTRY_IE)
377 /* Used by nl80211 before kmalloc'ing our regulatory domain */
378 bool reg_is_valid_request(const char *alpha2)
383 return alpha2_equal(last_request->alpha2, alpha2);
386 /* Sanity check on a regulatory rule */
387 static bool is_valid_reg_rule(const struct ieee80211_reg_rule *rule)
389 const struct ieee80211_freq_range *freq_range = &rule->freq_range;
392 if (freq_range->start_freq_khz == 0 || freq_range->end_freq_khz == 0)
395 if (freq_range->start_freq_khz > freq_range->end_freq_khz)
398 freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
400 if (freq_range->max_bandwidth_khz > freq_diff)
406 static bool is_valid_rd(const struct ieee80211_regdomain *rd)
408 const struct ieee80211_reg_rule *reg_rule = NULL;
411 if (!rd->n_reg_rules)
414 for (i = 0; i < rd->n_reg_rules; i++) {
415 reg_rule = &rd->reg_rules[i];
416 if (!is_valid_reg_rule(reg_rule))
423 /* Returns value in KHz */
424 static u32 freq_max_bandwidth(const struct ieee80211_freq_range *freq_range,
428 for (i = 0; i < ARRAY_SIZE(supported_bandwidths); i++) {
429 u32 start_freq_khz = freq - supported_bandwidths[i]/2;
430 u32 end_freq_khz = freq + supported_bandwidths[i]/2;
431 if (start_freq_khz >= freq_range->start_freq_khz &&
432 end_freq_khz <= freq_range->end_freq_khz)
433 return supported_bandwidths[i];
438 /* XXX: add support for the rest of enum nl80211_reg_rule_flags, we may
439 * want to just have the channel structure use these */
440 static u32 map_regdom_flags(u32 rd_flags)
442 u32 channel_flags = 0;
443 if (rd_flags & NL80211_RRF_PASSIVE_SCAN)
444 channel_flags |= IEEE80211_CHAN_PASSIVE_SCAN;
445 if (rd_flags & NL80211_RRF_NO_IBSS)
446 channel_flags |= IEEE80211_CHAN_NO_IBSS;
447 if (rd_flags & NL80211_RRF_DFS)
448 channel_flags |= IEEE80211_CHAN_RADAR;
449 return channel_flags;
453 * freq_reg_info - get regulatory information for the given frequency
454 * @center_freq: Frequency in KHz for which we want regulatory information for
455 * @bandwidth: the bandwidth requirement you have in KHz, if you do not have one
456 * you can set this to 0. If this frequency is allowed we then set
457 * this value to the maximum allowed bandwidth.
458 * @reg_rule: the regulatory rule which we have for this frequency
460 * Use this function to get the regulatory rule for a specific frequency.
462 static int freq_reg_info(u32 center_freq, u32 *bandwidth,
463 const struct ieee80211_reg_rule **reg_rule)
466 u32 max_bandwidth = 0;
468 if (!cfg80211_regdomain)
471 for (i = 0; i < cfg80211_regdomain->n_reg_rules; i++) {
472 const struct ieee80211_reg_rule *rr;
473 const struct ieee80211_freq_range *fr = NULL;
474 const struct ieee80211_power_rule *pr = NULL;
476 rr = &cfg80211_regdomain->reg_rules[i];
477 fr = &rr->freq_range;
478 pr = &rr->power_rule;
479 max_bandwidth = freq_max_bandwidth(fr, center_freq);
480 if (max_bandwidth && *bandwidth <= max_bandwidth) {
482 *bandwidth = max_bandwidth;
487 return !max_bandwidth;
490 static void handle_channel(struct ieee80211_channel *chan)
493 u32 flags = chan->orig_flags;
494 u32 max_bandwidth = 0;
495 const struct ieee80211_reg_rule *reg_rule = NULL;
496 const struct ieee80211_power_rule *power_rule = NULL;
498 r = freq_reg_info(MHZ_TO_KHZ(chan->center_freq),
499 &max_bandwidth, ®_rule);
502 flags |= IEEE80211_CHAN_DISABLED;
507 power_rule = ®_rule->power_rule;
509 chan->flags = flags | map_regdom_flags(reg_rule->flags);
510 chan->max_antenna_gain = min(chan->orig_mag,
511 (int) MBI_TO_DBI(power_rule->max_antenna_gain));
512 chan->max_bandwidth = KHZ_TO_MHZ(max_bandwidth);
514 chan->max_power = min(chan->orig_mpwr,
515 (int) MBM_TO_DBM(power_rule->max_eirp));
517 chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
520 static void handle_band(struct ieee80211_supported_band *sband)
524 for (i = 0; i < sband->n_channels; i++)
525 handle_channel(&sband->channels[i]);
528 static void update_all_wiphy_regulatory(enum reg_set_by setby)
530 struct cfg80211_registered_device *drv;
532 list_for_each_entry(drv, &cfg80211_drv_list, list)
533 wiphy_update_regulatory(&drv->wiphy, setby);
536 void wiphy_update_regulatory(struct wiphy *wiphy, enum reg_set_by setby)
538 enum ieee80211_band band;
539 for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
540 if (wiphy->bands[band])
541 handle_band(wiphy->bands[band]);
542 if (wiphy->reg_notifier)
543 wiphy->reg_notifier(wiphy, setby);
547 /* Caller must hold &cfg80211_drv_mutex */
548 int __regulatory_hint(struct wiphy *wiphy, enum reg_set_by set_by,
551 struct regulatory_request *request;
554 r = ignore_request(wiphy, set_by, alpha2);
559 case REGDOM_SET_BY_CORE:
560 case REGDOM_SET_BY_COUNTRY_IE:
561 case REGDOM_SET_BY_DRIVER:
562 case REGDOM_SET_BY_USER:
563 request = kzalloc(sizeof(struct regulatory_request),
568 request->alpha2[0] = alpha2[0];
569 request->alpha2[1] = alpha2[1];
570 request->initiator = set_by;
571 request->wiphy = wiphy;
574 last_request = request;
575 r = call_crda(alpha2);
576 #ifndef CONFIG_WIRELESS_OLD_REGULATORY
578 printk(KERN_ERR "cfg80211: Failed calling CRDA\n");
589 void regulatory_hint(struct wiphy *wiphy, const char *alpha2)
593 mutex_lock(&cfg80211_drv_mutex);
594 __regulatory_hint(wiphy, REGDOM_SET_BY_DRIVER, alpha2);
595 mutex_unlock(&cfg80211_drv_mutex);
597 EXPORT_SYMBOL(regulatory_hint);
600 static void print_rd_rules(const struct ieee80211_regdomain *rd)
603 const struct ieee80211_reg_rule *reg_rule = NULL;
604 const struct ieee80211_freq_range *freq_range = NULL;
605 const struct ieee80211_power_rule *power_rule = NULL;
607 printk(KERN_INFO "\t(start_freq - end_freq @ bandwidth), "
608 "(max_antenna_gain, max_eirp)\n");
610 for (i = 0; i < rd->n_reg_rules; i++) {
611 reg_rule = &rd->reg_rules[i];
612 freq_range = ®_rule->freq_range;
613 power_rule = ®_rule->power_rule;
615 /* There may not be documentation for max antenna gain
616 * in certain regions */
617 if (power_rule->max_antenna_gain)
618 printk(KERN_INFO "\t(%d KHz - %d KHz @ %d KHz), "
619 "(%d mBi, %d mBm)\n",
620 freq_range->start_freq_khz,
621 freq_range->end_freq_khz,
622 freq_range->max_bandwidth_khz,
623 power_rule->max_antenna_gain,
624 power_rule->max_eirp);
626 printk(KERN_INFO "\t(%d KHz - %d KHz @ %d KHz), "
628 freq_range->start_freq_khz,
629 freq_range->end_freq_khz,
630 freq_range->max_bandwidth_khz,
631 power_rule->max_eirp);
635 static void print_regdomain(const struct ieee80211_regdomain *rd)
638 if (is_world_regdom(rd->alpha2))
639 printk(KERN_INFO "cfg80211: World regulatory "
640 "domain updated:\n");
642 if (is_unknown_alpha2(rd->alpha2))
643 printk(KERN_INFO "cfg80211: Regulatory domain "
644 "changed to driver built-in settings "
645 "(unknown country)\n");
647 printk(KERN_INFO "cfg80211: Regulatory domain "
648 "changed to country: %c%c\n",
649 rd->alpha2[0], rd->alpha2[1]);
654 void print_regdomain_info(const struct ieee80211_regdomain *rd)
656 printk(KERN_INFO "cfg80211: Regulatory domain: %c%c\n",
657 rd->alpha2[0], rd->alpha2[1]);
661 /* Takes ownership of rd only if it doesn't fail */
662 static int __set_regdom(const struct ieee80211_regdomain *rd)
664 /* Some basic sanity checks first */
666 if (is_world_regdom(rd->alpha2)) {
667 if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
669 update_world_regdomain(rd);
673 if (!is_alpha2_set(rd->alpha2) && !is_an_alpha2(rd->alpha2) &&
674 !is_unknown_alpha2(rd->alpha2))
680 /* allow overriding the static definitions if CRDA is present */
681 if (!is_old_static_regdom(cfg80211_regdomain) &&
682 !regdom_changed(rd->alpha2))
685 /* Now lets set the regulatory domain, update all driver channels
686 * and finally inform them of what we have done, in case they want
687 * to review or adjust their own settings based on their own
688 * internal EEPROM data */
690 if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
695 /* Country IE parsing coming soon */
696 switch (last_request->initiator) {
697 case REGDOM_SET_BY_CORE:
698 case REGDOM_SET_BY_DRIVER:
699 case REGDOM_SET_BY_USER:
700 if (!is_valid_rd(rd)) {
701 printk(KERN_ERR "cfg80211: Invalid "
702 "regulatory domain detected:\n");
703 print_regdomain_info(rd);
707 case REGDOM_SET_BY_COUNTRY_IE: /* Not yet */
714 cfg80211_regdomain = rd;
720 /* Use this call to set the current regulatory domain. Conflicts with
721 * multiple drivers can be ironed out later. Caller must've already
722 * kmalloc'd the rd structure. Caller must hold cfg80211_drv_mutex */
723 int set_regdom(const struct ieee80211_regdomain *rd)
727 /* Note that this doesn't update the wiphys, this is done below */
728 r = __set_regdom(rd);
734 /* This would make this whole thing pointless */
735 BUG_ON(rd != cfg80211_regdomain);
737 /* update all wiphys now with the new established regulatory domain */
738 update_all_wiphy_regulatory(last_request->initiator);
745 int regulatory_init(void)
749 reg_pdev = platform_device_register_simple("regulatory", 0, NULL, 0);
750 if (IS_ERR(reg_pdev))
751 return PTR_ERR(reg_pdev);
753 #ifdef CONFIG_WIRELESS_OLD_REGULATORY
754 cfg80211_regdomain = static_regdom(ieee80211_regdom);
756 printk(KERN_INFO "cfg80211: Using static regulatory domain info\n");
757 print_regdomain_info(cfg80211_regdomain);
758 /* The old code still requests for a new regdomain and if
759 * you have CRDA you get it updated, otherwise you get
760 * stuck with the static values. We ignore "EU" code as
761 * that is not a valid ISO / IEC 3166 alpha2 */
762 if (ieee80211_regdom[0] != 'E' || ieee80211_regdom[1] != 'U')
763 err = __regulatory_hint(NULL, REGDOM_SET_BY_CORE,
766 cfg80211_regdomain = cfg80211_world_regdom;
768 err = __regulatory_hint(NULL, REGDOM_SET_BY_CORE, "00");
770 printk(KERN_ERR "cfg80211: calling CRDA failed - "
771 "unable to update world regulatory domain, "
772 "using static definition\n");
778 void regulatory_exit(void)
780 mutex_lock(&cfg80211_drv_mutex);
786 platform_device_unregister(reg_pdev);
788 mutex_unlock(&cfg80211_drv_mutex);