/* * Copyright 2002-2005, Instant802 Networks, Inc. * Copyright 2005-2006, Devicescape Software, Inc. * Copyright 2007 Johannes Berg <johannes@sipsolutions.net> * Copyright 2008 Luis R. Rodriguez <lrodriguz@atheros.com> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ /** * DOC: Wireless regulatory infrastructure * * The usual implementation is for a driver to read a device EEPROM to * determine which regulatory domain it should be operating under, then * looking up the allowable channels in a driver-local table and finally * registering those channels in the wiphy structure. * * Another set of compliance enforcement is for drivers to use their * own compliance limits which can be stored on the EEPROM. The host * driver or firmware may ensure these are used. * * In addition to all this we provide an extra layer of regulatory * conformance. For drivers which do not have any regulatory * information CRDA provides the complete regulatory solution. * For others it provides a community effort on further restrictions * to enhance compliance. * * Note: When number of rules --> infinity we will not be able to * index on alpha2 any more, instead we'll probably have to * rely on some SHA1 checksum of the regdomain for example. * */ #include <linux/kernel.h> #include <linux/list.h> #include <linux/random.h> #include <linux/nl80211.h> #include <linux/platform_device.h> #include <net/cfg80211.h> #include "core.h" #include "reg.h" #include "regdb.h" #include "nl80211.h" #ifdef CONFIG_CFG80211_REG_DEBUG #define REG_DBG_PRINT(format, args...) \ do { \ printk(KERN_DEBUG format , ## args); \ } while (0) #else #define REG_DBG_PRINT(args...) #endif /* Receipt of information from last regulatory request */ static struct regulatory_request *last_request; /* To trigger userspace events */ static struct platform_device *reg_pdev; /* * Central wireless core regulatory domains, we only need two, * the current one and a world regulatory domain in case we have no * information to give us an alpha2 */ const struct ieee80211_regdomain *cfg80211_regdomain; /* * We use this as a place for the rd structure built from the * last parsed country IE to rest until CRDA gets back to us with * what it thinks should apply for the same country */ static const struct ieee80211_regdomain *country_ie_regdomain; /* * Protects static reg.c components: * - cfg80211_world_regdom * - cfg80211_regdom * - country_ie_regdomain * - last_request */ DEFINE_MUTEX(reg_mutex); #define assert_reg_lock() WARN_ON(!mutex_is_locked(®_mutex)) /* Used to queue up regulatory hints */ static LIST_HEAD(reg_requests_list); static spinlock_t reg_requests_lock; /* Used to queue up beacon hints for review */ static LIST_HEAD(reg_pending_beacons); static spinlock_t reg_pending_beacons_lock; /* Used to keep track of processed beacon hints */ static LIST_HEAD(reg_beacon_list); struct reg_beacon { struct list_head list; struct ieee80211_channel chan; }; /* We keep a static world regulatory domain in case of the absence of CRDA */ static const struct ieee80211_regdomain world_regdom = { .n_reg_rules = 5, .alpha2 = "00", .reg_rules = { /* IEEE 802.11b/g, channels 1..11 */ REG_RULE(2412-10, 2462+10, 40, 6, 20, 0), /* IEEE 802.11b/g, channels 12..13. No HT40 * channel fits here. */ REG_RULE(2467-10, 2472+10, 20, 6, 20, NL80211_RRF_PASSIVE_SCAN | NL80211_RRF_NO_IBSS), /* IEEE 802.11 channel 14 - Only JP enables * this and for 802.11b only */ REG_RULE(2484-10, 2484+10, 20, 6, 20, NL80211_RRF_PASSIVE_SCAN | NL80211_RRF_NO_IBSS | NL80211_RRF_NO_OFDM), /* IEEE 802.11a, channel 36..48 */ REG_RULE(5180-10, 5240+10, 40, 6, 20, NL80211_RRF_PASSIVE_SCAN | NL80211_RRF_NO_IBSS), /* NB: 5260 MHz - 5700 MHz requies DFS */ /* IEEE 802.11a, channel 149..165 */ REG_RULE(5745-10, 5825+10, 40, 6, 20, NL80211_RRF_PASSIVE_SCAN | NL80211_RRF_NO_IBSS), } }; static const struct ieee80211_regdomain *cfg80211_world_regdom = &world_regdom; static char *ieee80211_regdom = "00"; static char user_alpha2[2]; module_param(ieee80211_regdom, charp, 0444); MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain code"); static void reset_regdomains(void) { /* avoid freeing static information or freeing something twice */ if (cfg80211_regdomain == cfg80211_world_regdom) cfg80211_regdomain = NULL; if (cfg80211_world_regdom == &world_regdom) cfg80211_world_regdom = NULL; if (cfg80211_regdomain == &world_regdom) cfg80211_regdomain = NULL; kfree(cfg80211_regdomain); kfree(cfg80211_world_regdom); cfg80211_world_regdom = &world_regdom; cfg80211_regdomain = NULL; } /* * Dynamic world regulatory domain requested by the wireless * core upon initialization */ static void update_world_regdomain(const struct ieee80211_regdomain *rd) { BUG_ON(!last_request); reset_regdomains(); cfg80211_world_regdom = rd; cfg80211_regdomain = rd; } bool is_world_regdom(const char *alpha2) { if (!alpha2) return false; if (alpha2[0] == '0' && alpha2[1] == '0') return true; return false; } static bool is_alpha2_set(const char *alpha2) { if (!alpha2) return false; if (alpha2[0] != 0 && alpha2[1] != 0) return true; return false; } static bool is_alpha_upper(char letter) { /* ASCII A - Z */ if (letter >= 65 && letter <= 90) return true; return false; } static bool is_unknown_alpha2(const char *alpha2) { if (!alpha2) return false; /* * Special case where regulatory domain was built by driver * but a specific alpha2 cannot be determined */ if (alpha2[0] == '9' && alpha2[1] == '9') return true; return false; } static bool is_intersected_alpha2(const char *alpha2) { if (!alpha2) return false; /* * Special case where regulatory domain is the * result of an intersection between two regulatory domain * structures */ if (alpha2[0] == '9' && alpha2[1] == '8') return true; return false; } static bool is_an_alpha2(const char *alpha2) { if (!alpha2) return false; if (is_alpha_upper(alpha2[0]) && is_alpha_upper(alpha2[1])) return true; return false; } static bool alpha2_equal(const char *alpha2_x, const char *alpha2_y) { if (!alpha2_x || !alpha2_y) return false; if (alpha2_x[0] == alpha2_y[0] && alpha2_x[1] == alpha2_y[1]) return true; return false; } static bool regdom_changes(const char *alpha2) { assert_cfg80211_lock(); if (!cfg80211_regdomain) return true; if (alpha2_equal(cfg80211_regdomain->alpha2, alpha2)) return false; return true; } /* * The NL80211_REGDOM_SET_BY_USER regdom alpha2 is cached, this lets * you know if a valid regulatory hint with NL80211_REGDOM_SET_BY_USER * has ever been issued. */ static bool is_user_regdom_saved(void) { if (user_alpha2[0] == '9' && user_alpha2[1] == '7') return false; /* This would indicate a mistake on the design */ if (WARN((!is_world_regdom(user_alpha2) && !is_an_alpha2(user_alpha2)), "Unexpected user alpha2: %c%c\n", user_alpha2[0], user_alpha2[1])) return false; return true; } /** * country_ie_integrity_changes - tells us if the country IE has changed * @checksum: checksum of country IE of fields we are interested in * * If the country IE has not changed you can ignore it safely. This is * useful to determine if two devices are seeing two different country IEs * even on the same alpha2. Note that this will return false if no IE has * been set on the wireless core yet. */ static bool country_ie_integrity_changes(u32 checksum) { /* If no IE has been set then the checksum doesn't change */ if (unlikely(!last_request->country_ie_checksum)) return false; if (unlikely(last_request->country_ie_checksum != checksum)) return true; return false; } static int reg_copy_regd(const struct ieee80211_regdomain **dst_regd, const struct ieee80211_regdomain *src_regd) { struct ieee80211_regdomain *regd; int size_of_regd = 0; unsigned int i; size_of_regd = sizeof(struct ieee80211_regdomain) + ((src_regd->n_reg_rules + 1) * sizeof(struct ieee80211_reg_rule)); regd = kzalloc(size_of_regd, GFP_KERNEL); if (!regd) return -ENOMEM; memcpy(regd, src_regd, sizeof(struct ieee80211_regdomain)); for (i = 0; i < src_regd->n_reg_rules; i++) memcpy(®d->reg_rules[i], &src_regd->reg_rules[i], sizeof(struct ieee80211_reg_rule)); *dst_regd = regd; return 0; } #ifdef CONFIG_CFG80211_INTERNAL_REGDB struct reg_regdb_search_request { char alpha2[2]; struct list_head list; }; static LIST_HEAD(reg_regdb_search_list); static DEFINE_MUTEX(reg_regdb_search_mutex); static void reg_regdb_search(struct work_struct *work) { struct reg_regdb_search_request *request; const struct ieee80211_regdomain *curdom, *regdom; int i, r; mutex_lock(®_regdb_search_mutex); while (!list_empty(®_regdb_search_list)) { request = list_first_entry(®_regdb_search_list, struct reg_regdb_search_request, list); list_del(&request->list); for (i=0; i<reg_regdb_size; i++) { curdom = reg_regdb[i]; if (!memcmp(request->alpha2, curdom->alpha2, 2)) { r = reg_copy_regd(®dom, curdom); if (r) break; mutex_lock(&cfg80211_mutex); set_regdom(regdom); mutex_unlock(&cfg80211_mutex); break; } } kfree(request); } mutex_unlock(®_regdb_search_mutex); } static DECLARE_WORK(reg_regdb_work, reg_regdb_search); static void reg_regdb_query(const char *alpha2) { struct reg_regdb_search_request *request; if (!alpha2) return; request = kzalloc(sizeof(struct reg_regdb_search_request), GFP_KERNEL); if (!request) return; memcpy(request->alpha2, alpha2, 2); mutex_lock(®_regdb_search_mutex); list_add_tail(&request->list, ®_regdb_search_list); mutex_unlock(®_regdb_search_mutex); schedule_work(®_regdb_work); } #else static inline void reg_regdb_query(const char *alpha2) {} #endif /* CONFIG_CFG80211_INTERNAL_REGDB */ /* * This lets us keep regulatory code which is updated on a regulatory * basis in userspace. */ static int call_crda(const char *alpha2) { char country_env[9 + 2] = "COUNTRY="; char *envp[] = { country_env, NULL }; if (!is_world_regdom((char *) alpha2)) printk(KERN_INFO "cfg80211: Calling CRDA for country: %c%c\n", alpha2[0], alpha2[1]); else printk(KERN_INFO "cfg80211: Calling CRDA to update world " "regulatory domain\n"); /* query internal regulatory database (if it exists) */ reg_regdb_query(alpha2); country_env[8] = alpha2[0]; country_env[9] = alpha2[1]; return kobject_uevent_env(®_pdev->dev.kobj, KOBJ_CHANGE, envp); } /* Used by nl80211 before kmalloc'ing our regulatory domain */ bool reg_is_valid_request(const char *alpha2) { assert_cfg80211_lock(); if (!last_request) return false; return alpha2_equal(last_request->alpha2, alpha2); } /* Sanity check on a regulatory rule */ static bool is_valid_reg_rule(const struct ieee80211_reg_rule *rule) { const struct ieee80211_freq_range *freq_range = &rule->freq_range; u32 freq_diff; if (freq_range->start_freq_khz <= 0 || freq_range->end_freq_khz <= 0) return false; if (freq_range->start_freq_khz > freq_range->end_freq_khz) return false; freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz; if (freq_range->end_freq_khz <= freq_range->start_freq_khz || freq_range->max_bandwidth_khz > freq_diff) return false; return true; } static bool is_valid_rd(const struct ieee80211_regdomain *rd) { const struct ieee80211_reg_rule *reg_rule = NULL; unsigned int i; if (!rd->n_reg_rules) return false; if (WARN_ON(rd->n_reg_rules > NL80211_MAX_SUPP_REG_RULES)) return false; for (i = 0; i < rd->n_reg_rules; i++) { reg_rule = &rd->reg_rules[i]; if (!is_valid_reg_rule(reg_rule)) return false; } return true; } static bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_range, u32 center_freq_khz, u32 bw_khz) { u32 start_freq_khz, end_freq_khz; start_freq_khz = center_freq_khz - (bw_khz/2); end_freq_khz = center_freq_khz + (bw_khz/2); if (start_freq_khz >= freq_range->start_freq_khz && end_freq_khz <= freq_range->end_freq_khz) return true; return false; } /** * freq_in_rule_band - tells us if a frequency is in a frequency band * @freq_range: frequency rule we want to query * @freq_khz: frequency we are inquiring about * * This lets us know if a specific frequency rule is or is not relevant to * a specific frequency's band. Bands are device specific and artificial * definitions (the "2.4 GHz band" and the "5 GHz band"), however it is * safe for now to assume that a frequency rule should not be part of a * frequency's band if the start freq or end freq are off by more than 2 GHz. * This resolution can be lowered and should be considered as we add * regulatory rule support for other "bands". **/ static bool freq_in_rule_band(const struct ieee80211_freq_range *freq_range, u32 freq_khz) { #define ONE_GHZ_IN_KHZ 1000000 if (abs(freq_khz - freq_range->start_freq_khz) <= (2 * ONE_GHZ_IN_KHZ)) return true; if (abs(freq_khz - freq_range->end_freq_khz) <= (2 * ONE_GHZ_IN_KHZ)) return true; return false; #undef ONE_GHZ_IN_KHZ } /* * This is a work around for sanity checking ieee80211_channel_to_frequency()'s * work. ieee80211_channel_to_frequency() can for example currently provide a * 2 GHz channel when in fact a 5 GHz channel was desired. An example would be * an AP providing channel 8 on a country IE triplet when it sent this on the * 5 GHz band, that channel is designed to be channel 8 on 5 GHz, not a 2 GHz * channel. * * This can be removed once ieee80211_channel_to_frequency() takes in a band. */ static bool chan_in_band(int chan, enum ieee80211_band band) { int center_freq = ieee80211_channel_to_frequency(chan); switch (band) { case IEEE80211_BAND_2GHZ: if (center_freq <= 2484) return true; return false; case IEEE80211_BAND_5GHZ: if (center_freq >= 5005) return true; return false; default: return false; } } /* * Some APs may send a country IE triplet for each channel they * support and while this is completely overkill and silly we still * need to support it. We avoid making a single rule for each channel * though and to help us with this we use this helper to find the * actual subband end channel. These type of country IE triplet * scenerios are handled then, all yielding two regulaotry rules from * parsing a country IE: * * [1] * [2] * [36] * [40] * * [1] * [2-4] * [5-12] * [36] * [40-44] * * [1-4] * [5-7] * [36-44] * [48-64] * * [36-36] * [40-40] * [44-44] * [48-48] * [52-52] * [56-56] * [60-60] * [64-64] * [100-100] * [104-104] * [108-108] * [112-112] * [116-116] * [120-120] * [124-124] * [128-128] * [132-132] * [136-136] * [140-140] * * Returns 0 if the IE has been found to be invalid in the middle * somewhere. */ static int max_subband_chan(enum ieee80211_band band, int orig_cur_chan, int orig_end_channel, s8 orig_max_power, u8 **country_ie, u8 *country_ie_len) { u8 *triplets_start = *country_ie; u8 len_at_triplet = *country_ie_len; int end_subband_chan = orig_end_channel; /* * We'll deal with padding for the caller unless * its not immediate and we don't process any channels */ if (*country_ie_len == 1) { *country_ie += 1; *country_ie_len -= 1; return orig_end_channel; } /* Move to the next triplet and then start search */ *country_ie += 3; *country_ie_len -= 3; if (!chan_in_band(orig_cur_chan, band)) return 0; while (*country_ie_len >= 3) { int end_channel = 0; struct ieee80211_country_ie_triplet *triplet = (struct ieee80211_country_ie_triplet *) *country_ie; int cur_channel = 0, next_expected_chan; /* means last triplet is completely unrelated to this one */ if (triplet->ext.reg_extension_id >= IEEE80211_COUNTRY_EXTENSION_ID) { *country_ie -= 3; *country_ie_len += 3; break; } if (triplet->chans.first_channel == 0) { *country_ie += 1; *country_ie_len -= 1; if (*country_ie_len != 0) return 0; break; } if (triplet->chans.num_channels == 0) return 0; /* Monitonically increasing channel order */ if (triplet->chans.first_channel <= end_subband_chan) return 0; if (!chan_in_band(triplet->chans.first_channel, band)) return 0; /* 2 GHz */ if (triplet->chans.first_channel <= 14) { end_channel = triplet->chans.first_channel + triplet->chans.num_channels - 1; } else { end_channel = triplet->chans.first_channel + (4 * (triplet->chans.num_channels - 1)); } if (!chan_in_band(end_channel, band)) return 0; if (orig_max_power != triplet->chans.max_power) { *country_ie -= 3; *country_ie_len += 3; break; } cur_channel = triplet->chans.first_channel; /* The key is finding the right next expected channel */ if (band == IEEE80211_BAND_2GHZ) next_expected_chan = end_subband_chan + 1; else next_expected_chan = end_subband_chan + 4; if (cur_channel != next_expected_chan) { *country_ie -= 3; *country_ie_len += 3; break; } end_subband_chan = end_channel; /* Move to the next one */ *country_ie += 3; *country_ie_len -= 3; /* * Padding needs to be dealt with if we processed * some channels. */ if (*country_ie_len == 1) { *country_ie += 1; *country_ie_len -= 1; break; } /* If seen, the IE is invalid */ if (*country_ie_len == 2) return 0; } if (end_subband_chan == orig_end_channel) { *country_ie = triplets_start; *country_ie_len = len_at_triplet; return orig_end_channel; } return end_subband_chan; } /* * Converts a country IE to a regulatory domain. A regulatory domain * structure has a lot of information which the IE doesn't yet have, * so for the other values we use upper max values as we will intersect * with our userspace regulatory agent to get lower bounds. */ static struct ieee80211_regdomain *country_ie_2_rd( enum ieee80211_band band, u8 *country_ie, u8 country_ie_len, u32 *checksum) { struct ieee80211_regdomain *rd = NULL; unsigned int i = 0; char alpha2[2]; u32 flags = 0; u32 num_rules = 0, size_of_regd = 0; u8 *triplets_start = NULL; u8 len_at_triplet = 0; /* the last channel we have registered in a subband (triplet) */ int last_sub_max_channel = 0; *checksum = 0xDEADBEEF; /* Country IE requirements */ BUG_ON(country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN || country_ie_len & 0x01); alpha2[0] = country_ie[0]; alpha2[1] = country_ie[1]; /* * Third octet can be: * 'I' - Indoor * 'O' - Outdoor * * anything else we assume is no restrictions */ if (country_ie[2] == 'I') flags = NL80211_RRF_NO_OUTDOOR; else if (country_ie[2] == 'O') flags = NL80211_RRF_NO_INDOOR; country_ie += 3; country_ie_len -= 3; triplets_start = country_ie; len_at_triplet = country_ie_len; *checksum ^= ((flags ^ alpha2[0] ^ alpha2[1]) << 8); /* * We need to build a reg rule for each triplet, but first we must * calculate the number of reg rules we will need. We will need one * for each channel subband */ while (country_ie_len >= 3) { int end_channel = 0; struct ieee80211_country_ie_triplet *triplet = (struct ieee80211_country_ie_triplet *) country_ie; int cur_sub_max_channel = 0, cur_channel = 0; if (triplet->ext.reg_extension_id >= IEEE80211_COUNTRY_EXTENSION_ID) { country_ie += 3; country_ie_len -= 3; continue; } /* * APs can add padding to make length divisible * by two, required by the spec. */ if (triplet->chans.first_channel == 0) { country_ie++; country_ie_len--; /* This is expected to be at the very end only */ if (country_ie_len != 0) return NULL; break; } if (triplet->chans.num_channels == 0) return NULL; if (!chan_in_band(triplet->chans.first_channel, band)) return NULL; /* 2 GHz */ if (band == IEEE80211_BAND_2GHZ) end_channel = triplet->chans.first_channel + triplet->chans.num_channels - 1; else /* * 5 GHz -- For example in country IEs if the first * channel given is 36 and the number of channels is 4 * then the individual channel numbers defined for the * 5 GHz PHY by these parameters are: 36, 40, 44, and 48 * and not 36, 37, 38, 39. * * See: http://tinyurl.com/11d-clarification */ end_channel = triplet->chans.first_channel + (4 * (triplet->chans.num_channels - 1)); cur_channel = triplet->chans.first_channel; /* * Enhancement for APs that send a triplet for every channel * or for whatever reason sends triplets with multiple channels * separated when in fact they should be together. */ end_channel = max_subband_chan(band, cur_channel, end_channel, triplet->chans.max_power, &country_ie, &country_ie_len); if (!end_channel) return NULL; if (!chan_in_band(end_channel, band)) return NULL; cur_sub_max_channel = end_channel; /* Basic sanity check */ if (cur_sub_max_channel < cur_channel) return NULL; /* * Do not allow overlapping channels. Also channels * passed in each subband must be monotonically * increasing */ if (last_sub_max_channel) { if (cur_channel <= last_sub_max_channel) return NULL; if (cur_sub_max_channel <= last_sub_max_channel) return NULL; } /* * When dot11RegulatoryClassesRequired is supported * we can throw ext triplets as part of this soup, * for now we don't care when those change as we * don't support them */ *checksum ^= ((cur_channel ^ cur_sub_max_channel) << 8) | ((cur_sub_max_channel ^ cur_sub_max_channel) << 16) | ((triplet->chans.max_power ^ cur_sub_max_channel) << 24); last_sub_max_channel = cur_sub_max_channel; num_rules++; if (country_ie_len >= 3) { country_ie += 3; country_ie_len -= 3; } /* * Note: this is not a IEEE requirement but * simply a memory requirement */ if (num_rules > NL80211_MAX_SUPP_REG_RULES) return NULL; } country_ie = triplets_start; country_ie_len = len_at_triplet; size_of_regd = sizeof(struct ieee80211_regdomain) + (num_rules * sizeof(struct ieee80211_reg_rule)); rd = kzalloc(size_of_regd, GFP_KERNEL); if (!rd) return NULL; rd->n_reg_rules = num_rules; rd->alpha2[0] = alpha2[0]; rd->alpha2[1] = alpha2[1]; /* This time around we fill in the rd */ while (country_ie_len >= 3) { int end_channel = 0; struct ieee80211_country_ie_triplet *triplet = (struct ieee80211_country_ie_triplet *) country_ie; struct ieee80211_reg_rule *reg_rule = NULL; struct ieee80211_freq_range *freq_range = NULL; struct ieee80211_power_rule *power_rule = NULL; /* * Must parse if dot11RegulatoryClassesRequired is true, * we don't support this yet */ if (triplet->ext.reg_extension_id >= IEEE80211_COUNTRY_EXTENSION_ID) { country_ie += 3; country_ie_len -= 3; continue; } if (triplet->chans.first_channel == 0) { country_ie++; country_ie_len--; break; } reg_rule = &rd->reg_rules[i]; freq_range = ®_rule->freq_range; power_rule = ®_rule->power_rule; reg_rule->flags = flags; /* 2 GHz */ if (band == IEEE80211_BAND_2GHZ) end_channel = triplet->chans.first_channel + triplet->chans.num_channels -1; else end_channel = triplet->chans.first_channel + (4 * (triplet->chans.num_channels - 1)); end_channel = max_subband_chan(band, triplet->chans.first_channel, end_channel, triplet->chans.max_power, &country_ie, &country_ie_len); /* * The +10 is since the regulatory domain expects * the actual band edge, not the center of freq for * its start and end freqs, assuming 20 MHz bandwidth on * the channels passed */ freq_range->start_freq_khz = MHZ_TO_KHZ(ieee80211_channel_to_frequency( triplet->chans.first_channel) - 10); freq_range->end_freq_khz = MHZ_TO_KHZ(ieee80211_channel_to_frequency( end_channel) + 10); /* * These are large arbitrary values we use to intersect later. * Increment this if we ever support >= 40 MHz channels * in IEEE 802.11 */ freq_range->max_bandwidth_khz = MHZ_TO_KHZ(40); power_rule->max_antenna_gain = DBI_TO_MBI(100); power_rule->max_eirp = DBM_TO_MBM(triplet->chans.max_power); i++; if (country_ie_len >= 3) { country_ie += 3; country_ie_len -= 3; } BUG_ON(i > NL80211_MAX_SUPP_REG_RULES); } return rd; } /* * Helper for regdom_intersect(), this does the real * mathematical intersection fun */ static int reg_rules_intersect( const struct ieee80211_reg_rule *rule1, const struct ieee80211_reg_rule *rule2, struct ieee80211_reg_rule *intersected_rule) { const struct ieee80211_freq_range *freq_range1, *freq_range2; struct ieee80211_freq_range *freq_range; const struct ieee80211_power_rule *power_rule1, *power_rule2; struct ieee80211_power_rule *power_rule; u32 freq_diff; freq_range1 = &rule1->freq_range; freq_range2 = &rule2->freq_range; freq_range = &intersected_rule->freq_range; power_rule1 = &rule1->power_rule; power_rule2 = &rule2->power_rule; power_rule = &intersected_rule->power_rule; freq_range->start_freq_khz = max(freq_range1->start_freq_khz, freq_range2->start_freq_khz); freq_range->end_freq_khz = min(freq_range1->end_freq_khz, freq_range2->end_freq_khz); freq_range->max_bandwidth_khz = min(freq_range1->max_bandwidth_khz, freq_range2->max_bandwidth_khz); freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz; if (freq_range->max_bandwidth_khz > freq_diff) freq_range->max_bandwidth_khz = freq_diff; power_rule->max_eirp = min(power_rule1->max_eirp, power_rule2->max_eirp); power_rule->max_antenna_gain = min(power_rule1->max_antenna_gain, power_rule2->max_antenna_gain); intersected_rule->flags = (rule1->flags | rule2->flags); if (!is_valid_reg_rule(intersected_rule)) return -EINVAL; return 0; } /** * regdom_intersect - do the intersection between two regulatory domains * @rd1: first regulatory domain * @rd2: second regulatory domain * * Use this function to get the intersection between two regulatory domains. * Once completed we will mark the alpha2 for the rd as intersected, "98", * as no one single alpha2 can represent this regulatory domain. * * Returns a pointer to the regulatory domain structure which will hold the * resulting intersection of rules between rd1 and rd2. We will * kzalloc() this structure for you. */ static struct ieee80211_regdomain *regdom_intersect( const struct ieee80211_regdomain *rd1, const struct ieee80211_regdomain *rd2) { int r, size_of_regd; unsigned int x, y; unsigned int num_rules = 0, rule_idx = 0; const struct ieee80211_reg_rule *rule1, *rule2; struct ieee80211_reg_rule *intersected_rule; struct ieee80211_regdomain *rd; /* This is just a dummy holder to help us count */ struct ieee80211_reg_rule irule; /* Uses the stack temporarily for counter arithmetic */ intersected_rule = &irule; memset(intersected_rule, 0, sizeof(struct ieee80211_reg_rule)); if (!rd1 || !rd2) return NULL; /* * First we get a count of the rules we'll need, then we actually * build them. This is to so we can malloc() and free() a * regdomain once. The reason we use reg_rules_intersect() here * is it will return -EINVAL if the rule computed makes no sense. * All rules that do check out OK are valid. */ for (x = 0; x < rd1->n_reg_rules; x++) { rule1 = &rd1->reg_rules[x]; for (y = 0; y < rd2->n_reg_rules; y++) { rule2 = &rd2->reg_rules[y]; if (!reg_rules_intersect(rule1, rule2, intersected_rule)) num_rules++; memset(intersected_rule, 0, sizeof(struct ieee80211_reg_rule)); } } if (!num_rules) return NULL; size_of_regd = sizeof(struct ieee80211_regdomain) + ((num_rules + 1) * sizeof(struct ieee80211_reg_rule)); rd = kzalloc(size_of_regd, GFP_KERNEL); if (!rd) return NULL; for (x = 0; x < rd1->n_reg_rules; x++) { rule1 = &rd1->reg_rules[x]; for (y = 0; y < rd2->n_reg_rules; y++) { rule2 = &rd2->reg_rules[y]; /* * This time around instead of using the stack lets * write to the target rule directly saving ourselves * a memcpy() */ intersected_rule = &rd->reg_rules[rule_idx]; r = reg_rules_intersect(rule1, rule2, intersected_rule); /* * No need to memset here the intersected rule here as * we're not using the stack anymore */ if (r) continue; rule_idx++; } } if (rule_idx != num_rules) { kfree(rd); return NULL; } rd->n_reg_rules = num_rules; rd->alpha2[0] = '9'; rd->alpha2[1] = '8'; return rd; } /* * XXX: add support for the rest of enum nl80211_reg_rule_flags, we may * want to just have the channel structure use these */ static u32 map_regdom_flags(u32 rd_flags) { u32 channel_flags = 0; if (rd_flags & NL80211_RRF_PASSIVE_SCAN) channel_flags |= IEEE80211_CHAN_PASSIVE_SCAN; if (rd_flags & NL80211_RRF_NO_IBSS) channel_flags |= IEEE80211_CHAN_NO_IBSS; if (rd_flags & NL80211_RRF_DFS) channel_flags |= IEEE80211_CHAN_RADAR; return channel_flags; } static int freq_reg_info_regd(struct wiphy *wiphy, u32 center_freq, u32 desired_bw_khz, const struct ieee80211_reg_rule **reg_rule, const struct ieee80211_regdomain *custom_regd) { int i; bool band_rule_found = false; const struct ieee80211_regdomain *regd; bool bw_fits = false; if (!desired_bw_khz) desired_bw_khz = MHZ_TO_KHZ(20); regd = custom_regd ? custom_regd : cfg80211_regdomain; /* * Follow the driver's regulatory domain, if present, unless a country * IE has been processed or a user wants to help complaince further */ if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE && last_request->initiator != NL80211_REGDOM_SET_BY_USER && wiphy->regd) regd = wiphy->regd; if (!regd) return -EINVAL; for (i = 0; i < regd->n_reg_rules; i++) { const struct ieee80211_reg_rule *rr; const struct ieee80211_freq_range *fr = NULL; const struct ieee80211_power_rule *pr = NULL; rr = ®d->reg_rules[i]; fr = &rr->freq_range; pr = &rr->power_rule; /* * We only need to know if one frequency rule was * was in center_freq's band, that's enough, so lets * not overwrite it once found */ if (!band_rule_found) band_rule_found = freq_in_rule_band(fr, center_freq); bw_fits = reg_does_bw_fit(fr, center_freq, desired_bw_khz); if (band_rule_found && bw_fits) { *reg_rule = rr; return 0; } } if (!band_rule_found) return -ERANGE; return -EINVAL; } EXPORT_SYMBOL(freq_reg_info); int freq_reg_info(struct wiphy *wiphy, u32 center_freq, u32 desired_bw_khz, const struct ieee80211_reg_rule **reg_rule) { assert_cfg80211_lock(); return freq_reg_info_regd(wiphy, center_freq, desired_bw_khz, reg_rule, NULL); } /* * Note that right now we assume the desired channel bandwidth * is always 20 MHz for each individual channel (HT40 uses 20 MHz * per channel, the primary and the extension channel). To support * smaller custom bandwidths such as 5 MHz or 10 MHz we'll need a * new ieee80211_channel.target_bw and re run the regulatory check * on the wiphy with the target_bw specified. Then we can simply use * that below for the desired_bw_khz below. */ static void handle_channel(struct wiphy *wiphy, enum ieee80211_band band, unsigned int chan_idx) { int r; u32 flags, bw_flags = 0; u32 desired_bw_khz = MHZ_TO_KHZ(20); const struct ieee80211_reg_rule *reg_rule = NULL; const struct ieee80211_power_rule *power_rule = NULL; const struct ieee80211_freq_range *freq_range = NULL; struct ieee80211_supported_band *sband; struct ieee80211_channel *chan; struct wiphy *request_wiphy = NULL; assert_cfg80211_lock(); request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx); sband = wiphy->bands[band]; BUG_ON(chan_idx >= sband->n_channels); chan = &sband->channels[chan_idx]; flags = chan->orig_flags; r = freq_reg_info(wiphy, MHZ_TO_KHZ(chan->center_freq), desired_bw_khz, ®_rule); if (r) { /* * This means no regulatory rule was found in the country IE * with a frequency range on the center_freq's band, since * IEEE-802.11 allows for a country IE to have a subset of the * regulatory information provided in a country we ignore * disabling the channel unless at least one reg rule was * found on the center_freq's band. For details see this * clarification: * * http://tinyurl.com/11d-clarification */ if (r == -ERANGE && last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE) { REG_DBG_PRINT("cfg80211: Leaving channel %d MHz " "intact on %s - no rule found in band on " "Country IE\n", chan->center_freq, wiphy_name(wiphy)); } else { /* * In this case we know the country IE has at least one reg rule * for the band so we respect its band definitions */ if (last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE) REG_DBG_PRINT("cfg80211: Disabling " "channel %d MHz on %s due to " "Country IE\n", chan->center_freq, wiphy_name(wiphy)); flags |= IEEE80211_CHAN_DISABLED; chan->flags = flags; } return; } power_rule = ®_rule->power_rule; freq_range = ®_rule->freq_range; if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40)) bw_flags = IEEE80211_CHAN_NO_HT40; if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER && request_wiphy && request_wiphy == wiphy && request_wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY) { /* * This gaurantees the driver's requested regulatory domain * will always be used as a base for further regulatory * settings */ chan->flags = chan->orig_flags = map_regdom_flags(reg_rule->flags) | bw_flags; chan->max_antenna_gain = chan->orig_mag = (int) MBI_TO_DBI(power_rule->max_antenna_gain); chan->max_power = chan->orig_mpwr = (int) MBM_TO_DBM(power_rule->max_eirp); return; } chan->flags = flags | bw_flags | map_regdom_flags(reg_rule->flags); chan->max_antenna_gain = min(chan->orig_mag, (int) MBI_TO_DBI(power_rule->max_antenna_gain)); if (chan->orig_mpwr) chan->max_power = min(chan->orig_mpwr, (int) MBM_TO_DBM(power_rule->max_eirp)); else chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp); } static void handle_band(struct wiphy *wiphy, enum ieee80211_band band) { unsigned int i; struct ieee80211_supported_band *sband; BUG_ON(!wiphy->bands[band]); sband = wiphy->bands[band]; for (i = 0; i < sband->n_channels; i++) handle_channel(wiphy, band, i); } static bool ignore_reg_update(struct wiphy *wiphy, enum nl80211_reg_initiator initiator) { if (!last_request) return true; if (initiator == NL80211_REGDOM_SET_BY_CORE && wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY) return true; /* * wiphy->regd will be set once the device has its own * desired regulatory domain set */ if (wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY && !wiphy->regd && !is_world_regdom(last_request->alpha2)) return true; return false; } static void update_all_wiphy_regulatory(enum nl80211_reg_initiator initiator) { struct cfg80211_registered_device *rdev; list_for_each_entry(rdev, &cfg80211_rdev_list, list) wiphy_update_regulatory(&rdev->wiphy, initiator); } static void handle_reg_beacon(struct wiphy *wiphy, unsigned int chan_idx, struct reg_beacon *reg_beacon) { struct ieee80211_supported_band *sband; struct ieee80211_channel *chan; bool channel_changed = false; struct ieee80211_channel chan_before; assert_cfg80211_lock(); sband = wiphy->bands[reg_beacon->chan.band]; chan = &sband->channels[chan_idx]; if (likely(chan->center_freq != reg_beacon->chan.center_freq)) return; if (chan->beacon_found) return; chan->beacon_found = true; if (wiphy->flags & WIPHY_FLAG_DISABLE_BEACON_HINTS) return; chan_before.center_freq = chan->center_freq; chan_before.flags = chan->flags; if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN) { chan->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN; channel_changed = true; } if (chan->flags & IEEE80211_CHAN_NO_IBSS) { chan->flags &= ~IEEE80211_CHAN_NO_IBSS; channel_changed = true; } if (channel_changed) nl80211_send_beacon_hint_event(wiphy, &chan_before, chan); } /* * Called when a scan on a wiphy finds a beacon on * new channel */ static void wiphy_update_new_beacon(struct wiphy *wiphy, struct reg_beacon *reg_beacon) { unsigned int i; struct ieee80211_supported_band *sband; assert_cfg80211_lock(); if (!wiphy->bands[reg_beacon->chan.band]) return; sband = wiphy->bands[reg_beacon->chan.band]; for (i = 0; i < sband->n_channels; i++) handle_reg_beacon(wiphy, i, reg_beacon); } /* * Called upon reg changes or a new wiphy is added */ static void wiphy_update_beacon_reg(struct wiphy *wiphy) { unsigned int i; struct ieee80211_supported_band *sband; struct reg_beacon *reg_beacon; assert_cfg80211_lock(); if (list_empty(®_beacon_list)) return; list_for_each_entry(reg_beacon, ®_beacon_list, list) { if (!wiphy->bands[reg_beacon->chan.band]) continue; sband = wiphy->bands[reg_beacon->chan.band]; for (i = 0; i < sband->n_channels; i++) handle_reg_beacon(wiphy, i, reg_beacon); } } static bool reg_is_world_roaming(struct wiphy *wiphy) { if (is_world_regdom(cfg80211_regdomain->alpha2) || (wiphy->regd && is_world_regdom(wiphy->regd->alpha2))) return true; if (last_request && last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE && wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY) return true; return false; } /* Reap the advantages of previously found beacons */ static void reg_process_beacons(struct wiphy *wiphy) { /* * Means we are just firing up cfg80211, so no beacons would * have been processed yet. */ if (!last_request) return; if (!reg_is_world_roaming(wiphy)) return; wiphy_update_beacon_reg(wiphy); } static bool is_ht40_not_allowed(struct ieee80211_channel *chan) { if (!chan) return true; if (chan->flags & IEEE80211_CHAN_DISABLED) return true; /* This would happen when regulatory rules disallow HT40 completely */ if (IEEE80211_CHAN_NO_HT40 == (chan->flags & (IEEE80211_CHAN_NO_HT40))) return true; return false; } static void reg_process_ht_flags_channel(struct wiphy *wiphy, enum ieee80211_band band, unsigned int chan_idx) { struct ieee80211_supported_band *sband; struct ieee80211_channel *channel; struct ieee80211_channel *channel_before = NULL, *channel_after = NULL; unsigned int i; assert_cfg80211_lock(); sband = wiphy->bands[band]; BUG_ON(chan_idx >= sband->n_channels); channel = &sband->channels[chan_idx]; if (is_ht40_not_allowed(channel)) { channel->flags |= IEEE80211_CHAN_NO_HT40; return; } /* * We need to ensure the extension channels exist to * be able to use HT40- or HT40+, this finds them (or not) */ for (i = 0; i < sband->n_channels; i++) { struct ieee80211_channel *c = &sband->channels[i]; if (c->center_freq == (channel->center_freq - 20)) channel_before = c; if (c->center_freq == (channel->center_freq + 20)) channel_after = c; } /* * Please note that this assumes target bandwidth is 20 MHz, * if that ever changes we also need to change the below logic * to include that as well. */ if (is_ht40_not_allowed(channel_before)) channel->flags |= IEEE80211_CHAN_NO_HT40MINUS; else channel->flags &= ~IEEE80211_CHAN_NO_HT40MINUS; if (is_ht40_not_allowed(channel_after)) channel->flags |= IEEE80211_CHAN_NO_HT40PLUS; else channel->flags &= ~IEEE80211_CHAN_NO_HT40PLUS; } static void reg_process_ht_flags_band(struct wiphy *wiphy, enum ieee80211_band band) { unsigned int i; struct ieee80211_supported_band *sband; BUG_ON(!wiphy->bands[band]); sband = wiphy->bands[band]; for (i = 0; i < sband->n_channels; i++) reg_process_ht_flags_channel(wiphy, band, i); } static void reg_process_ht_flags(struct wiphy *wiphy) { enum ieee80211_band band; if (!wiphy) return; for (band = 0; band < IEEE80211_NUM_BANDS; band++) { if (wiphy->bands[band]) reg_process_ht_flags_band(wiphy, band); } } void wiphy_update_regulatory(struct wiphy *wiphy, enum nl80211_reg_initiator initiator) { enum ieee80211_band band; if (ignore_reg_update(wiphy, initiator)) goto out; for (band = 0; band < IEEE80211_NUM_BANDS; band++) { if (wiphy->bands[band]) handle_band(wiphy, band); } out: reg_process_beacons(wiphy); reg_process_ht_flags(wiphy); if (wiphy->reg_notifier) wiphy->reg_notifier(wiphy, last_request); } static void handle_channel_custom(struct wiphy *wiphy, enum ieee80211_band band, unsigned int chan_idx, const struct ieee80211_regdomain *regd) { int r; u32 desired_bw_khz = MHZ_TO_KHZ(20); u32 bw_flags = 0; const struct ieee80211_reg_rule *reg_rule = NULL; const struct ieee80211_power_rule *power_rule = NULL; const struct ieee80211_freq_range *freq_range = NULL; struct ieee80211_supported_band *sband; struct ieee80211_channel *chan; assert_reg_lock(); sband = wiphy->bands[band]; BUG_ON(chan_idx >= sband->n_channels); chan = &sband->channels[chan_idx]; r = freq_reg_info_regd(wiphy, MHZ_TO_KHZ(chan->center_freq), desired_bw_khz, ®_rule, regd); if (r) { chan->flags = IEEE80211_CHAN_DISABLED; return; } power_rule = ®_rule->power_rule; freq_range = ®_rule->freq_range; if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40)) bw_flags = IEEE80211_CHAN_NO_HT40; chan->flags |= map_regdom_flags(reg_rule->flags) | bw_flags; chan->max_antenna_gain = (int) MBI_TO_DBI(power_rule->max_antenna_gain); chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp); } static void handle_band_custom(struct wiphy *wiphy, enum ieee80211_band band, const struct ieee80211_regdomain *regd) { unsigned int i; struct ieee80211_supported_band *sband; BUG_ON(!wiphy->bands[band]); sband = wiphy->bands[band]; for (i = 0; i < sband->n_channels; i++) handle_channel_custom(wiphy, band, i, regd); } /* Used by drivers prior to wiphy registration */ void wiphy_apply_custom_regulatory(struct wiphy *wiphy, const struct ieee80211_regdomain *regd) { enum ieee80211_band band; unsigned int bands_set = 0; mutex_lock(®_mutex); for (band = 0; band < IEEE80211_NUM_BANDS; band++) { if (!wiphy->bands[band]) continue; handle_band_custom(wiphy, band, regd); bands_set++; } mutex_unlock(®_mutex); /* * no point in calling this if it won't have any effect * on your device's supportd bands. */ WARN_ON(!bands_set); } EXPORT_SYMBOL(wiphy_apply_custom_regulatory); /* * Return value which can be used by ignore_request() to indicate * it has been determined we should intersect two regulatory domains */ #define REG_INTERSECT 1 /* This has the logic which determines when a new request * should be ignored. */ static int ignore_request(struct wiphy *wiphy, struct regulatory_request *pending_request) { struct wiphy *last_wiphy = NULL; assert_cfg80211_lock(); /* All initial requests are respected */ if (!last_request) return 0; switch (pending_request->initiator) { case NL80211_REGDOM_SET_BY_CORE: return 0; case NL80211_REGDOM_SET_BY_COUNTRY_IE: last_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx); if (unlikely(!is_an_alpha2(pending_request->alpha2))) return -EINVAL; if (last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE) { if (last_wiphy != wiphy) { /* * Two cards with two APs claiming different * Country IE alpha2s. We could * intersect them, but that seems unlikely * to be correct. Reject second one for now. */ if (regdom_changes(pending_request->alpha2)) return -EOPNOTSUPP; return -EALREADY; } /* * Two consecutive Country IE hints on the same wiphy. * This should be picked up early by the driver/stack */ if (WARN_ON(regdom_changes(pending_request->alpha2))) return 0; return -EALREADY; } return REG_INTERSECT; case NL80211_REGDOM_SET_BY_DRIVER: if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE) { if (regdom_changes(pending_request->alpha2)) return 0; return -EALREADY; } /* * This would happen if you unplug and plug your card * back in or if you add a new device for which the previously * loaded card also agrees on the regulatory domain. */ if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER && !regdom_changes(pending_request->alpha2)) return -EALREADY; return REG_INTERSECT; case NL80211_REGDOM_SET_BY_USER: if (last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE) return REG_INTERSECT; /* * If the user knows better the user should set the regdom * to their country before the IE is picked up */ if (last_request->initiator == NL80211_REGDOM_SET_BY_USER && last_request->intersect) return -EOPNOTSUPP; /* * Process user requests only after previous user/driver/core * requests have been processed */ if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE || last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER || last_request->initiator == NL80211_REGDOM_SET_BY_USER) { if (regdom_changes(last_request->alpha2)) return -EAGAIN; } if (!regdom_changes(pending_request->alpha2)) return -EALREADY; return 0; } return -EINVAL; } /** * __regulatory_hint - hint to the wireless core a regulatory domain * @wiphy: if the hint comes from country information from an AP, this * is required to be set to the wiphy that received the information * @pending_request: the regulatory request currently being processed * * The Wireless subsystem can use this function to hint to the wireless core * what it believes should be the current regulatory domain. * * Returns zero if all went fine, %-EALREADY if a regulatory domain had * already been set or other standard error codes. * * Caller must hold &cfg80211_mutex and ®_mutex */ static int __regulatory_hint(struct wiphy *wiphy, struct regulatory_request *pending_request) { bool intersect = false; int r = 0; assert_cfg80211_lock(); r = ignore_request(wiphy, pending_request); if (r == REG_INTERSECT) { if (pending_request->initiator == NL80211_REGDOM_SET_BY_DRIVER) { r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain); if (r) { kfree(pending_request); return r; } } intersect = true; } else if (r) { /* * If the regulatory domain being requested by the * driver has already been set just copy it to the * wiphy */ if (r == -EALREADY && pending_request->initiator == NL80211_REGDOM_SET_BY_DRIVER) { r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain); if (r) { kfree(pending_request); return r; } r = -EALREADY; goto new_request; } kfree(pending_request); return r; } new_request: kfree(last_request); last_request = pending_request; last_request->intersect = intersect; pending_request = NULL; if (last_request->initiator == NL80211_REGDOM_SET_BY_USER) { user_alpha2[0] = last_request->alpha2[0]; user_alpha2[1] = last_request->alpha2[1]; } /* When r == REG_INTERSECT we do need to call CRDA */ if (r < 0) { /* * Since CRDA will not be called in this case as we already * have applied the requested regulatory domain before we just * inform userspace we have processed the request */ if (r == -EALREADY) nl80211_send_reg_change_event(last_request); return r; } return call_crda(last_request->alpha2); } /* This processes *all* regulatory hints */ static void reg_process_hint(struct regulatory_request *reg_request) { int r = 0; struct wiphy *wiphy = NULL; BUG_ON(!reg_request->alpha2); mutex_lock(&cfg80211_mutex); mutex_lock(®_mutex); if (wiphy_idx_valid(reg_request->wiphy_idx)) wiphy = wiphy_idx_to_wiphy(reg_request->wiphy_idx); if (reg_request->initiator == NL80211_REGDOM_SET_BY_DRIVER && !wiphy) { kfree(reg_request); goto out; } r = __regulatory_hint(wiphy, reg_request); /* This is required so that the orig_* parameters are saved */ if (r == -EALREADY && wiphy && wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY) wiphy_update_regulatory(wiphy, reg_request->initiator); out: mutex_unlock(®_mutex); mutex_unlock(&cfg80211_mutex); } /* Processes regulatory hints, this is all the NL80211_REGDOM_SET_BY_* */ static void reg_process_pending_hints(void) { struct regulatory_request *reg_request; spin_lock(®_requests_lock); while (!list_empty(®_requests_list)) { reg_request = list_first_entry(®_requests_list, struct regulatory_request, list); list_del_init(®_request->list); spin_unlock(®_requests_lock); reg_process_hint(reg_request); spin_lock(®_requests_lock); } spin_unlock(®_requests_lock); } /* Processes beacon hints -- this has nothing to do with country IEs */ static void reg_process_pending_beacon_hints(void) { struct cfg80211_registered_device *rdev; struct reg_beacon *pending_beacon, *tmp; /* * No need to hold the reg_mutex here as we just touch wiphys * and do not read or access regulatory variables. */ mutex_lock(&cfg80211_mutex); /* This goes through the _pending_ beacon list */ spin_lock_bh(®_pending_beacons_lock); if (list_empty(®_pending_beacons)) { spin_unlock_bh(®_pending_beacons_lock); goto out; } list_for_each_entry_safe(pending_beacon, tmp, ®_pending_beacons, list) { list_del_init(&pending_beacon->list); /* Applies the beacon hint to current wiphys */ list_for_each_entry(rdev, &cfg80211_rdev_list, list) wiphy_update_new_beacon(&rdev->wiphy, pending_beacon); /* Remembers the beacon hint for new wiphys or reg changes */ list_add_tail(&pending_beacon->list, ®_beacon_list); } spin_unlock_bh(®_pending_beacons_lock); out: mutex_unlock(&cfg80211_mutex); } static void reg_todo(struct work_struct *work) { reg_process_pending_hints(); reg_process_pending_beacon_hints(); } static DECLARE_WORK(reg_work, reg_todo); static void queue_regulatory_request(struct regulatory_request *request) { spin_lock(®_requests_lock); list_add_tail(&request->list, ®_requests_list); spin_unlock(®_requests_lock); schedule_work(®_work); } /* * Core regulatory hint -- happens during cfg80211_init() * and when we restore regulatory settings. */ static int regulatory_hint_core(const char *alpha2) { struct regulatory_request *request; kfree(last_request); last_request = NULL; request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL); if (!request) return -ENOMEM; request->alpha2[0] = alpha2[0]; request->alpha2[1] = alpha2[1]; request->initiator = NL80211_REGDOM_SET_BY_CORE; /* * This ensures last_request is populated once modules * come swinging in and calling regulatory hints and * wiphy_apply_custom_regulatory(). */ reg_process_hint(request); return 0; } /* User hints */ int regulatory_hint_user(const char *alpha2) { struct regulatory_request *request; BUG_ON(!alpha2); request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL); if (!request) return -ENOMEM; request->wiphy_idx = WIPHY_IDX_STALE; request->alpha2[0] = alpha2[0]; request->alpha2[1] = alpha2[1]; request->initiator = NL80211_REGDOM_SET_BY_USER; queue_regulatory_request(request); return 0; } /* Driver hints */ int regulatory_hint(struct wiphy *wiphy, const char *alpha2) { struct regulatory_request *request; BUG_ON(!alpha2); BUG_ON(!wiphy); request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL); if (!request) return -ENOMEM; request->wiphy_idx = get_wiphy_idx(wiphy); /* Must have registered wiphy first */ BUG_ON(!wiphy_idx_valid(request->wiphy_idx)); request->alpha2[0] = alpha2[0]; request->alpha2[1] = alpha2[1]; request->initiator = NL80211_REGDOM_SET_BY_DRIVER; queue_regulatory_request(request); return 0; } EXPORT_SYMBOL(regulatory_hint); /* Caller must hold reg_mutex */ static bool reg_same_country_ie_hint(struct wiphy *wiphy, u32 country_ie_checksum) { struct wiphy *request_wiphy; assert_reg_lock(); if (unlikely(last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE)) return false; request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx); if (!request_wiphy) return false; if (likely(request_wiphy != wiphy)) return !country_ie_integrity_changes(country_ie_checksum); /* * We should not have let these through at this point, they * should have been picked up earlier by the first alpha2 check * on the device */ if (WARN_ON(!country_ie_integrity_changes(country_ie_checksum))) return true; return false; } /* * We hold wdev_lock() here so we cannot hold cfg80211_mutex() and * therefore cannot iterate over the rdev list here. */ void regulatory_hint_11d(struct wiphy *wiphy, enum ieee80211_band band, u8 *country_ie, u8 country_ie_len) { struct ieee80211_regdomain *rd = NULL; char alpha2[2]; u32 checksum = 0; enum environment_cap env = ENVIRON_ANY; struct regulatory_request *request; mutex_lock(®_mutex); if (unlikely(!last_request)) goto out; /* IE len must be evenly divisible by 2 */ if (country_ie_len & 0x01) goto out; if (country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN) goto out; /* * Pending country IE processing, this can happen after we * call CRDA and wait for a response if a beacon was received before * we were able to process the last regulatory_hint_11d() call */ if (country_ie_regdomain) goto out; alpha2[0] = country_ie[0]; alpha2[1] = country_ie[1]; if (country_ie[2] == 'I') env = ENVIRON_INDOOR; else if (country_ie[2] == 'O') env = ENVIRON_OUTDOOR; /* * We will run this only upon a successful connection on cfg80211. * We leave conflict resolution to the workqueue, where can hold * cfg80211_mutex. */ if (likely(last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE && wiphy_idx_valid(last_request->wiphy_idx))) goto out; rd = country_ie_2_rd(band, country_ie, country_ie_len, &checksum); if (!rd) { REG_DBG_PRINT("cfg80211: Ignoring bogus country IE\n"); goto out; } /* * This will not happen right now but we leave it here for the * the future when we want to add suspend/resume support and having * the user move to another country after doing so, or having the user * move to another AP. Right now we just trust the first AP. * * If we hit this before we add this support we want to be informed of * it as it would indicate a mistake in the current design */ if (WARN_ON(reg_same_country_ie_hint(wiphy, checksum))) goto free_rd_out; request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL); if (!request) goto free_rd_out; /* * We keep this around for when CRDA comes back with a response so * we can intersect with that */ country_ie_regdomain = rd; request->wiphy_idx = get_wiphy_idx(wiphy); request->alpha2[0] = rd->alpha2[0]; request->alpha2[1] = rd->alpha2[1]; request->initiator = NL80211_REGDOM_SET_BY_COUNTRY_IE; request->country_ie_checksum = checksum; request->country_ie_env = env; mutex_unlock(®_mutex); queue_regulatory_request(request); return; free_rd_out: kfree(rd); out: mutex_unlock(®_mutex); } static void restore_alpha2(char *alpha2, bool reset_user) { /* indicates there is no alpha2 to consider for restoration */ alpha2[0] = '9'; alpha2[1] = '7'; /* The user setting has precedence over the module parameter */ if (is_user_regdom_saved()) { /* Unless we're asked to ignore it and reset it */ if (reset_user) { REG_DBG_PRINT("cfg80211: Restoring regulatory settings " "including user preference\n"); user_alpha2[0] = '9'; user_alpha2[1] = '7'; /* * If we're ignoring user settings, we still need to * check the module parameter to ensure we put things * back as they were for a full restore. */ if (!is_world_regdom(ieee80211_regdom)) { REG_DBG_PRINT("cfg80211: Keeping preference on " "module parameter ieee80211_regdom: %c%c\n", ieee80211_regdom[0], ieee80211_regdom[1]); alpha2[0] = ieee80211_regdom[0]; alpha2[1] = ieee80211_regdom[1]; } } else { REG_DBG_PRINT("cfg80211: Restoring regulatory settings " "while preserving user preference for: %c%c\n", user_alpha2[0], user_alpha2[1]); alpha2[0] = user_alpha2[0]; alpha2[1] = user_alpha2[1]; } } else if (!is_world_regdom(ieee80211_regdom)) { REG_DBG_PRINT("cfg80211: Keeping preference on " "module parameter ieee80211_regdom: %c%c\n", ieee80211_regdom[0], ieee80211_regdom[1]); alpha2[0] = ieee80211_regdom[0]; alpha2[1] = ieee80211_regdom[1]; } else REG_DBG_PRINT("cfg80211: Restoring regulatory settings\n"); } /* * Restoring regulatory settings involves ingoring any * possibly stale country IE information and user regulatory * settings if so desired, this includes any beacon hints * learned as we could have traveled outside to another country * after disconnection. To restore regulatory settings we do * exactly what we did at bootup: * * - send a core regulatory hint * - send a user regulatory hint if applicable * * Device drivers that send a regulatory hint for a specific country * keep their own regulatory domain on wiphy->regd so that does does * not need to be remembered. */ static void restore_regulatory_settings(bool reset_user) { char alpha2[2]; struct reg_beacon *reg_beacon, *btmp; mutex_lock(&cfg80211_mutex); mutex_lock(®_mutex); reset_regdomains(); restore_alpha2(alpha2, reset_user); /* Clear beacon hints */ spin_lock_bh(®_pending_beacons_lock); if (!list_empty(®_pending_beacons)) { list_for_each_entry_safe(reg_beacon, btmp, ®_pending_beacons, list) { list_del(®_beacon->list); kfree(reg_beacon); } } spin_unlock_bh(®_pending_beacons_lock); if (!list_empty(®_beacon_list)) { list_for_each_entry_safe(reg_beacon, btmp, ®_beacon_list, list) { list_del(®_beacon->list); kfree(reg_beacon); } } /* First restore to the basic regulatory settings */ cfg80211_regdomain = cfg80211_world_regdom; mutex_unlock(®_mutex); mutex_unlock(&cfg80211_mutex); regulatory_hint_core(cfg80211_regdomain->alpha2); /* * This restores the ieee80211_regdom module parameter * preference or the last user requested regulatory * settings, user regulatory settings takes precedence. */ if (is_an_alpha2(alpha2)) regulatory_hint_user(user_alpha2); } void regulatory_hint_disconnect(void) { REG_DBG_PRINT("cfg80211: All devices are disconnected, going to " "restore regulatory settings\n"); restore_regulatory_settings(false); } static bool freq_is_chan_12_13_14(u16 freq) { if (freq == ieee80211_channel_to_frequency(12) || freq == ieee80211_channel_to_frequency(13) || freq == ieee80211_channel_to_frequency(14)) return true; return false; } int regulatory_hint_found_beacon(struct wiphy *wiphy, struct ieee80211_channel *beacon_chan, gfp_t gfp) { struct reg_beacon *reg_beacon; if (likely((beacon_chan->beacon_found || (beacon_chan->flags & IEEE80211_CHAN_RADAR) || (beacon_chan->band == IEEE80211_BAND_2GHZ && !freq_is_chan_12_13_14(beacon_chan->center_freq))))) return 0; reg_beacon = kzalloc(sizeof(struct reg_beacon), gfp); if (!reg_beacon) return -ENOMEM; REG_DBG_PRINT("cfg80211: Found new beacon on " "frequency: %d MHz (Ch %d) on %s\n", beacon_chan->center_freq, ieee80211_frequency_to_channel(beacon_chan->center_freq), wiphy_name(wiphy)); memcpy(®_beacon->chan, beacon_chan, sizeof(struct ieee80211_channel)); /* * Since we can be called from BH or and non-BH context * we must use spin_lock_bh() */ spin_lock_bh(®_pending_beacons_lock); list_add_tail(®_beacon->list, ®_pending_beacons); spin_unlock_bh(®_pending_beacons_lock); schedule_work(®_work); return 0; } static void print_rd_rules(const struct ieee80211_regdomain *rd) { unsigned int i; const struct ieee80211_reg_rule *reg_rule = NULL; const struct ieee80211_freq_range *freq_range = NULL; const struct ieee80211_power_rule *power_rule = NULL; printk(KERN_INFO " (start_freq - end_freq @ bandwidth), " "(max_antenna_gain, max_eirp)\n"); for (i = 0; i < rd->n_reg_rules; i++) { reg_rule = &rd->reg_rules[i]; freq_range = ®_rule->freq_range; power_rule = ®_rule->power_rule; /* * There may not be documentation for max antenna gain * in certain regions */ if (power_rule->max_antenna_gain) printk(KERN_INFO " (%d KHz - %d KHz @ %d KHz), " "(%d mBi, %d mBm)\n", freq_range->start_freq_khz, freq_range->end_freq_khz, freq_range->max_bandwidth_khz, power_rule->max_antenna_gain, power_rule->max_eirp); else printk(KERN_INFO " (%d KHz - %d KHz @ %d KHz), " "(N/A, %d mBm)\n", freq_range->start_freq_khz, freq_range->end_freq_khz, freq_range->max_bandwidth_khz, power_rule->max_eirp); } } static void print_regdomain(const struct ieee80211_regdomain *rd) { if (is_intersected_alpha2(rd->alpha2)) { if (last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE) { struct cfg80211_registered_device *rdev; rdev = cfg80211_rdev_by_wiphy_idx( last_request->wiphy_idx); if (rdev) { printk(KERN_INFO "cfg80211: Current regulatory " "domain updated by AP to: %c%c\n", rdev->country_ie_alpha2[0], rdev->country_ie_alpha2[1]); } else printk(KERN_INFO "cfg80211: Current regulatory " "domain intersected:\n"); } else printk(KERN_INFO "cfg80211: Current regulatory " "domain intersected:\n"); } else if (is_world_regdom(rd->alpha2)) printk(KERN_INFO "cfg80211: World regulatory " "domain updated:\n"); else { if (is_unknown_alpha2(rd->alpha2)) printk(KERN_INFO "cfg80211: Regulatory domain " "changed to driver built-in settings " "(unknown country)\n"); else printk(KERN_INFO "cfg80211: Regulatory domain " "changed to country: %c%c\n", rd->alpha2[0], rd->alpha2[1]); } print_rd_rules(rd); } static void print_regdomain_info(const struct ieee80211_regdomain *rd) { printk(KERN_INFO "cfg80211: Regulatory domain: %c%c\n", rd->alpha2[0], rd->alpha2[1]); print_rd_rules(rd); } #ifdef CONFIG_CFG80211_REG_DEBUG static void reg_country_ie_process_debug( const struct ieee80211_regdomain *rd, const struct ieee80211_regdomain *country_ie_regdomain, const struct ieee80211_regdomain *intersected_rd) { printk(KERN_DEBUG "cfg80211: Received country IE:\n"); print_regdomain_info(country_ie_regdomain); printk(KERN_DEBUG "cfg80211: CRDA thinks this should applied:\n"); print_regdomain_info(rd); if (intersected_rd) { printk(KERN_DEBUG "cfg80211: We intersect both of these " "and get:\n"); print_regdomain_info(intersected_rd); return; } printk(KERN_DEBUG "cfg80211: Intersection between both failed\n"); } #else static inline void reg_country_ie_process_debug( const struct ieee80211_regdomain *rd, const struct ieee80211_regdomain *country_ie_regdomain, const struct ieee80211_regdomain *intersected_rd) { } #endif /* Takes ownership of rd only if it doesn't fail */ static int __set_regdom(const struct ieee80211_regdomain *rd) { const struct ieee80211_regdomain *intersected_rd = NULL; struct cfg80211_registered_device *rdev = NULL; struct wiphy *request_wiphy; /* Some basic sanity checks first */ if (is_world_regdom(rd->alpha2)) { if (WARN_ON(!reg_is_valid_request(rd->alpha2))) return -EINVAL; update_world_regdomain(rd); return 0; } if (!is_alpha2_set(rd->alpha2) && !is_an_alpha2(rd->alpha2) && !is_unknown_alpha2(rd->alpha2)) return -EINVAL; if (!last_request) return -EINVAL; /* * Lets only bother proceeding on the same alpha2 if the current * rd is non static (it means CRDA was present and was used last) * and the pending request came in from a country IE */ if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) { /* * If someone else asked us to change the rd lets only bother * checking if the alpha2 changes if CRDA was already called */ if (!regdom_changes(rd->alpha2)) return -EINVAL; } /* * Now lets set the regulatory domain, update all driver channels * and finally inform them of what we have done, in case they want * to review or adjust their own settings based on their own * internal EEPROM data */ if (WARN_ON(!reg_is_valid_request(rd->alpha2))) return -EINVAL; if (!is_valid_rd(rd)) { printk(KERN_ERR "cfg80211: Invalid " "regulatory domain detected:\n"); print_regdomain_info(rd); return -EINVAL; } request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx); if (!last_request->intersect) { int r; if (last_request->initiator != NL80211_REGDOM_SET_BY_DRIVER) { reset_regdomains(); cfg80211_regdomain = rd; return 0; } /* * For a driver hint, lets copy the regulatory domain the * driver wanted to the wiphy to deal with conflicts */ /* * Userspace could have sent two replies with only * one kernel request. */ if (request_wiphy->regd) return -EALREADY; r = reg_copy_regd(&request_wiphy->regd, rd); if (r) return r; reset_regdomains(); cfg80211_regdomain = rd; return 0; } /* Intersection requires a bit more work */ if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) { intersected_rd = regdom_intersect(rd, cfg80211_regdomain); if (!intersected_rd) return -EINVAL; /* * We can trash what CRDA provided now. * However if a driver requested this specific regulatory * domain we keep it for its private use */ if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER) request_wiphy->regd = rd; else kfree(rd); rd = NULL; reset_regdomains(); cfg80211_regdomain = intersected_rd; return 0; } /* * Country IE requests are handled a bit differently, we intersect * the country IE rd with what CRDA believes that country should have */ /* * Userspace could have sent two replies with only * one kernel request. By the second reply we would have * already processed and consumed the country_ie_regdomain. */ if (!country_ie_regdomain) return -EALREADY; BUG_ON(rd == country_ie_regdomain); /* * Intersect what CRDA returned and our what we * had built from the Country IE received */ intersected_rd = regdom_intersect(rd, country_ie_regdomain); reg_country_ie_process_debug(rd, country_ie_regdomain, intersected_rd); kfree(country_ie_regdomain); country_ie_regdomain = NULL; if (!intersected_rd) return -EINVAL; rdev = wiphy_to_dev(request_wiphy); rdev->country_ie_alpha2[0] = rd->alpha2[0]; rdev->country_ie_alpha2[1] = rd->alpha2[1]; rdev->env = last_request->country_ie_env; BUG_ON(intersected_rd == rd); kfree(rd); rd = NULL; reset_regdomains(); cfg80211_regdomain = intersected_rd; return 0; } /* * Use this call to set the current regulatory domain. Conflicts with * multiple drivers can be ironed out later. Caller must've already * kmalloc'd the rd structure. Caller must hold cfg80211_mutex */ int set_regdom(const struct ieee80211_regdomain *rd) { int r; assert_cfg80211_lock(); mutex_lock(®_mutex); /* Note that this doesn't update the wiphys, this is done below */ r = __set_regdom(rd); if (r) { kfree(rd); mutex_unlock(®_mutex); return r; } /* This would make this whole thing pointless */ if (!last_request->intersect) BUG_ON(rd != cfg80211_regdomain); /* update all wiphys now with the new established regulatory domain */ update_all_wiphy_regulatory(last_request->initiator); print_regdomain(cfg80211_regdomain); nl80211_send_reg_change_event(last_request); mutex_unlock(®_mutex); return r; } /* Caller must hold cfg80211_mutex */ void reg_device_remove(struct wiphy *wiphy) { struct wiphy *request_wiphy = NULL; assert_cfg80211_lock(); mutex_lock(®_mutex); kfree(wiphy->regd); if (last_request) request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx); if (!request_wiphy || request_wiphy != wiphy) goto out; last_request->wiphy_idx = WIPHY_IDX_STALE; last_request->country_ie_env = ENVIRON_ANY; out: mutex_unlock(®_mutex); } int regulatory_init(void) { int err = 0; reg_pdev = platform_device_register_simple("regulatory", 0, NULL, 0); if (IS_ERR(reg_pdev)) return PTR_ERR(reg_pdev); spin_lock_init(®_requests_lock); spin_lock_init(®_pending_beacons_lock); cfg80211_regdomain = cfg80211_world_regdom; user_alpha2[0] = '9'; user_alpha2[1] = '7'; /* We always try to get an update for the static regdomain */ err = regulatory_hint_core(cfg80211_regdomain->alpha2); if (err) { if (err == -ENOMEM) return err; /* * N.B. kobject_uevent_env() can fail mainly for when we're out * memory which is handled and propagated appropriately above * but it can also fail during a netlink_broadcast() or during * early boot for call_usermodehelper(). For now treat these * errors as non-fatal. */ printk(KERN_ERR "cfg80211: kobject_uevent_env() was unable " "to call CRDA during init"); #ifdef CONFIG_CFG80211_REG_DEBUG /* We want to find out exactly why when debugging */ WARN_ON(err); #endif } /* * Finally, if the user set the module parameter treat it * as a user hint. */ if (!is_world_regdom(ieee80211_regdom)) regulatory_hint_user(ieee80211_regdom); return 0; } void regulatory_exit(void) { struct regulatory_request *reg_request, *tmp; struct reg_beacon *reg_beacon, *btmp; cancel_work_sync(®_work); mutex_lock(&cfg80211_mutex); mutex_lock(®_mutex); reset_regdomains(); kfree(country_ie_regdomain); country_ie_regdomain = NULL; kfree(last_request); platform_device_unregister(reg_pdev); spin_lock_bh(®_pending_beacons_lock); if (!list_empty(®_pending_beacons)) { list_for_each_entry_safe(reg_beacon, btmp, ®_pending_beacons, list) { list_del(®_beacon->list); kfree(reg_beacon); } } spin_unlock_bh(®_pending_beacons_lock); if (!list_empty(®_beacon_list)) { list_for_each_entry_safe(reg_beacon, btmp, ®_beacon_list, list) { list_del(®_beacon->list); kfree(reg_beacon); } } spin_lock(®_requests_lock); if (!list_empty(®_requests_list)) { list_for_each_entry_safe(reg_request, tmp, ®_requests_list, list) { list_del(®_request->list); kfree(reg_request); } } spin_unlock(®_requests_lock); mutex_unlock(®_mutex); mutex_unlock(&cfg80211_mutex); }