reg.c 64.4 KB
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/*
 * Copyright 2002-2005, Instant802 Networks, Inc.
 * Copyright 2005-2006, Devicescape Software, Inc.
 * Copyright 2007	Johannes Berg <johannes@sipsolutions.net>
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 * Copyright 2008	Luis R. Rodriguez <lrodriguz@atheros.com>
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 *
 * 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.
 */

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/**
 * DOC: Wireless regulatory infrastructure
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 *
 * 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.
 *
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 * 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.
 *
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 */
#include <linux/kernel.h>
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#include <linux/list.h>
#include <linux/random.h>
#include <linux/nl80211.h>
#include <linux/platform_device.h>
#include <net/cfg80211.h>
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#include "core.h"
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#include "reg.h"
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#include "regdb.h"
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#include "nl80211.h"
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#ifdef CONFIG_CFG80211_REG_DEBUG
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#define REG_DBG_PRINT(format, args...) \
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	do { \
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		printk(KERN_DEBUG format , ## args); \
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	} while (0)
#else
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#define REG_DBG_PRINT(args...)
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#endif

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/* Receipt of information from last regulatory request */
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static struct regulatory_request *last_request;
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/* To trigger userspace events */
static struct platform_device *reg_pdev;
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/*
 * Central wireless core regulatory domains, we only need two,
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 * the current one and a world regulatory domain in case we have no
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 * information to give us an alpha2
 */
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const struct ieee80211_regdomain *cfg80211_regdomain;
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/*
 * We use this as a place for the rd structure built from the
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 * last parsed country IE to rest until CRDA gets back to us with
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 * what it thinks should apply for the same country
 */
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static const struct ieee80211_regdomain *country_ie_regdomain;

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/*
 * 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(&reg_mutex))

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/* Used to queue up regulatory hints */
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static LIST_HEAD(reg_requests_list);
static spinlock_t reg_requests_lock;

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/* 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;
};

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/* We keep a static world regulatory domain in case of the absence of CRDA */
static const struct ieee80211_regdomain world_regdom = {
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	.n_reg_rules = 5,
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	.alpha2 =  "00",
	.reg_rules = {
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		/* IEEE 802.11b/g, channels 1..11 */
		REG_RULE(2412-10, 2462+10, 40, 6, 20, 0),
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		/* IEEE 802.11b/g, channels 12..13. No HT40
		 * channel fits here. */
		REG_RULE(2467-10, 2472+10, 20, 6, 20,
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			NL80211_RRF_PASSIVE_SCAN |
			NL80211_RRF_NO_IBSS),
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		/* 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 */
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		REG_RULE(5180-10, 5240+10, 40, 6, 20,
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                        NL80211_RRF_PASSIVE_SCAN |
                        NL80211_RRF_NO_IBSS),
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		/* NB: 5260 MHz - 5700 MHz requies DFS */

		/* IEEE 802.11a, channel 149..165 */
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		REG_RULE(5745-10, 5825+10, 40, 6, 20,
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			NL80211_RRF_PASSIVE_SCAN |
			NL80211_RRF_NO_IBSS),
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	}
};

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static const struct ieee80211_regdomain *cfg80211_world_regdom =
	&world_regdom;
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static char *ieee80211_regdom = "00";

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module_param(ieee80211_regdom, charp, 0444);
MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain code");

static void reset_regdomains(void)
{
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	/* 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);
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	cfg80211_world_regdom = &world_regdom;
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	cfg80211_regdomain = NULL;
}

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/*
 * Dynamic world regulatory domain requested by the wireless
 * core upon initialization
 */
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static void update_world_regdomain(const struct ieee80211_regdomain *rd)
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{
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	BUG_ON(!last_request);
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	reset_regdomains();

	cfg80211_world_regdom = rd;
	cfg80211_regdomain = rd;
}

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bool is_world_regdom(const char *alpha2)
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{
	if (!alpha2)
		return false;
	if (alpha2[0] == '0' && alpha2[1] == '0')
		return true;
	return false;
}
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static bool is_alpha2_set(const char *alpha2)
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{
	if (!alpha2)
		return false;
	if (alpha2[0] != 0 && alpha2[1] != 0)
		return true;
	return false;
}
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static bool is_alpha_upper(char letter)
{
	/* ASCII A - Z */
	if (letter >= 65 && letter <= 90)
		return true;
	return false;
}
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static bool is_unknown_alpha2(const char *alpha2)
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{
	if (!alpha2)
		return false;
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	/*
	 * Special case where regulatory domain was built by driver
	 * but a specific alpha2 cannot be determined
	 */
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	if (alpha2[0] == '9' && alpha2[1] == '9')
		return true;
	return false;
}
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static bool is_intersected_alpha2(const char *alpha2)
{
	if (!alpha2)
		return false;
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	/*
	 * Special case where regulatory domain is the
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	 * result of an intersection between two regulatory domain
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	 * structures
	 */
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	if (alpha2[0] == '9' && alpha2[1] == '8')
		return true;
	return false;
}

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static bool is_an_alpha2(const char *alpha2)
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{
	if (!alpha2)
		return false;
	if (is_alpha_upper(alpha2[0]) && is_alpha_upper(alpha2[1]))
		return true;
	return false;
}
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static bool alpha2_equal(const char *alpha2_x, const char *alpha2_y)
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{
	if (!alpha2_x || !alpha2_y)
		return false;
	if (alpha2_x[0] == alpha2_y[0] &&
		alpha2_x[1] == alpha2_y[1])
		return true;
	return false;
}

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static bool regdom_changes(const char *alpha2)
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{
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	assert_cfg80211_lock();

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	if (!cfg80211_regdomain)
		return true;
	if (alpha2_equal(cfg80211_regdomain->alpha2, alpha2))
		return false;
	return true;
}

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/**
 * 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;
}

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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(&regd->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_SPINLOCK(reg_regdb_search_lock);

static void reg_regdb_search(struct work_struct *work)
{
	struct reg_regdb_search_request *request;
	const struct ieee80211_regdomain *curdom, *regdom;
	int i, r;

	spin_lock(&reg_regdb_search_lock);
	while (!list_empty(&reg_regdb_search_list)) {
		request = list_first_entry(&reg_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(&regdom, curdom);
				if (r)
					break;
				spin_unlock(&reg_regdb_search_lock);
				mutex_lock(&cfg80211_mutex);
				set_regdom(regdom);
				mutex_unlock(&cfg80211_mutex);
				spin_lock(&reg_regdb_search_lock);
				break;
			}
		}

		kfree(request);
	}
	spin_unlock(&reg_regdb_search_lock);
}

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);

	spin_lock(&reg_regdb_search_lock);
	list_add_tail(&request->list, &reg_regdb_search_list);
	spin_unlock(&reg_regdb_search_lock);

	schedule_work(&reg_regdb_work);
}
#else
static inline void reg_regdb_query(const char *alpha2) {}
#endif /* CONFIG_CFG80211_INTERNAL_REGDB */

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/*
 * This lets us keep regulatory code which is updated on a regulatory
 * basis in userspace.
 */
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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");

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	/* query internal regulatory database (if it exists) */
	reg_regdb_query(alpha2);

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	country_env[8] = alpha2[0];
	country_env[9] = alpha2[1];

	return kobject_uevent_env(&reg_pdev->dev.kobj, KOBJ_CHANGE, envp);
}

/* Used by nl80211 before kmalloc'ing our regulatory domain */
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bool reg_is_valid_request(const char *alpha2)
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{
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	assert_cfg80211_lock();

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	if (!last_request)
		return false;

	return alpha2_equal(last_request->alpha2, alpha2);
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}
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/* Sanity check on a regulatory rule */
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static bool is_valid_reg_rule(const struct ieee80211_reg_rule *rule)
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{
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	const struct ieee80211_freq_range *freq_range = &rule->freq_range;
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	u32 freq_diff;

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	if (freq_range->start_freq_khz <= 0 || freq_range->end_freq_khz <= 0)
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		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;

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	if (freq_range->end_freq_khz <= freq_range->start_freq_khz ||
			freq_range->max_bandwidth_khz > freq_diff)
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		return false;

	return true;
}

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static bool is_valid_rd(const struct ieee80211_regdomain *rd)
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{
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	const struct ieee80211_reg_rule *reg_rule = NULL;
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	unsigned int i;
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	if (!rd->n_reg_rules)
		return false;
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	if (WARN_ON(rd->n_reg_rules > NL80211_MAX_SUPP_REG_RULES))
		return false;

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	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;
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}

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static bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_range,
			    u32 center_freq_khz,
			    u32 bw_khz)
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{
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	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;
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}
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/**
 * 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
}

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/*
 * 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(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;
	enum ieee80211_band band;

	/*
	 * 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 (orig_cur_chan <= 14)
		band = IEEE80211_BAND_2GHZ;
	else
		band = IEEE80211_BAND_5GHZ;

	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;
		enum ieee80211_band next_band = IEEE80211_BAND_2GHZ;

		/* 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;
		}

		/* Monitonically increasing channel order */
		if (triplet->chans.first_channel <= end_subband_chan)
			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));
			next_band = IEEE80211_BAND_5GHZ;
		}

		if (band != next_band) {
			*country_ie -= 3;
			*country_ie_len += 3;
			break;
		}

		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;
}

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/*
 * Converts a country IE to a regulatory domain. A regulatory domain
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 * 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
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 * with our userspace regulatory agent to get lower bounds.
 */
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static struct ieee80211_regdomain *country_ie_2_rd(
				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);

709 710
	/*
	 * We need to build a reg rule for each triplet, but first we must
711
	 * calculate the number of reg rules we will need. We will need one
712 713
	 * for each channel subband
	 */
714
	while (country_ie_len >= 3) {
715
		int end_channel = 0;
716 717 718 719 720 721 722 723 724 725 726
		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;
		}

727 728 729 730 731 732 733 734 735 736 737 738 739
		/*
		 * 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;
		}

740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756
		/* 2 GHz */
		if (triplet->chans.first_channel <= 14)
			end_channel = triplet->chans.first_channel +
				triplet->chans.num_channels;
		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));

757
		cur_channel = triplet->chans.first_channel;
758 759 760 761 762 763 764 765 766 767 768 769 770 771

		/*
		 * 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(cur_channel,
					       end_channel,
					       triplet->chans.max_power,
					       &country_ie,
					       &country_ie_len);
		if (!end_channel)
			return NULL;

772
		cur_sub_max_channel = end_channel;
773 774 775 776 777

		/* Basic sanity check */
		if (cur_sub_max_channel < cur_channel)
			return NULL;

778 779
		/*
		 * Do not allow overlapping channels. Also channels
780
		 * passed in each subband must be monotonically
781 782
		 * increasing
		 */
783 784 785 786 787 788 789
		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;
		}

790 791
		/*
		 * When dot11RegulatoryClassesRequired is supported
792 793
		 * we can throw ext triplets as part of this soup,
		 * for now we don't care when those change as we
794 795
		 * don't support them
		 */
796 797 798 799 800 801 802 803
		*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++;

804 805 806 807 808
		if (country_ie_len >= 3) {
			country_ie += 3;
			country_ie_len -= 3;
		}

809 810 811 812
		/*
		 * Note: this is not a IEEE requirement but
		 * simply a memory requirement
		 */
813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832
		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) {
833
		int end_channel = 0;
834 835 836 837 838 839
		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;

840 841 842 843
		/*
		 * Must parse if dot11RegulatoryClassesRequired is true,
		 * we don't support this yet
		 */
844 845 846 847 848 849 850
		if (triplet->ext.reg_extension_id >=
				IEEE80211_COUNTRY_EXTENSION_ID) {
			country_ie += 3;
			country_ie_len -= 3;
			continue;
		}

851 852 853 854 855 856
		if (triplet->chans.first_channel == 0) {
			country_ie++;
			country_ie_len--;
			break;
		}

857 858 859 860 861 862
		reg_rule = &rd->reg_rules[i];
		freq_range = &reg_rule->freq_range;
		power_rule = &reg_rule->power_rule;

		reg_rule->flags = flags;

863 864 865 866 867 868 869 870
		/* 2 GHz */
		if (triplet->chans.first_channel <= 14)
			end_channel = triplet->chans.first_channel +
				triplet->chans.num_channels;
		else
			end_channel =  triplet->chans.first_channel +
				(4 * (triplet->chans.num_channels - 1));

871 872 873 874 875 876
		end_channel = max_subband_chan(triplet->chans.first_channel,
					       end_channel,
					       triplet->chans.max_power,
					       &country_ie,
					       &country_ie_len);

877 878
		/*
		 * The +10 is since the regulatory domain expects
879 880
		 * the actual band edge, not the center of freq for
		 * its start and end freqs, assuming 20 MHz bandwidth on
881 882
		 * the channels passed
		 */
883 884 885 886 887
		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(
888
				end_channel) + 10);
889

890 891 892 893 894
		/*
		 * These are large arbitrary values we use to intersect later.
		 * Increment this if we ever support >= 40 MHz channels
		 * in IEEE 802.11
		 */
895 896
		freq_range->max_bandwidth_khz = MHZ_TO_KHZ(40);
		power_rule->max_antenna_gain = DBI_TO_MBI(100);
897
		power_rule->max_eirp = DBM_TO_MBM(triplet->chans.max_power);
898 899 900

		i++;

901 902 903 904 905
		if (country_ie_len >= 3) {
			country_ie += 3;
			country_ie_len -= 3;
		}

906 907 908 909 910 911 912
		BUG_ON(i > NL80211_MAX_SUPP_REG_RULES);
	}

	return rd;
}


913 914 915 916
/*
 * Helper for regdom_intersect(), this does the real
 * mathematical intersection fun
 */
917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993
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;

994 995
	/*
	 * First we get a count of the rules we'll need, then we actually
996 997 998
	 * 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.
999 1000
	 * All rules that do check out OK are valid.
	 */
1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027

	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];
1028 1029
			/*
			 * This time around instead of using the stack lets
1030
			 * write to the target rule directly saving ourselves
1031 1032
			 * a memcpy()
			 */
1033 1034 1035
			intersected_rule = &rd->reg_rules[rule_idx];
			r = reg_rules_intersect(rule1, rule2,
				intersected_rule);
1036 1037 1038 1039
			/*
			 * No need to memset here the intersected rule here as
			 * we're not using the stack anymore
			 */
1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057
			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;
}

1058 1059 1060 1061
/*
 * XXX: add support for the rest of enum nl80211_reg_rule_flags, we may
 * want to just have the channel structure use these
 */
1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073
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;
}

1074 1075
static int freq_reg_info_regd(struct wiphy *wiphy,
			      u32 center_freq,
1076
			      u32 desired_bw_khz,
1077 1078
			      const struct ieee80211_reg_rule **reg_rule,
			      const struct ieee80211_regdomain *custom_regd)
1079 1080
{
	int i;
1081
	bool band_rule_found = false;
1082
	const struct ieee80211_regdomain *regd;
1083 1084 1085 1086
	bool bw_fits = false;

	if (!desired_bw_khz)
		desired_bw_khz = MHZ_TO_KHZ(20);
1087

1088
	regd = custom_regd ? custom_regd : cfg80211_regdomain;
1089

1090 1091 1092 1093
	/*
	 * Follow the driver's regulatory domain, if present, unless a country
	 * IE has been processed or a user wants to help complaince further
	 */
1094 1095
	if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
	    last_request->initiator != NL80211_REGDOM_SET_BY_USER &&
1096 1097 1098 1099
	    wiphy->regd)
		regd = wiphy->regd;

	if (!regd)
1100 1101
		return -EINVAL;

1102
	for (i = 0; i < regd->n_reg_rules; i++) {
1103 1104 1105 1106
		const struct ieee80211_reg_rule *rr;
		const struct ieee80211_freq_range *fr = NULL;
		const struct ieee80211_power_rule *pr = NULL;

1107
		rr = &regd->reg_rules[i];
1108 1109
		fr = &rr->freq_range;
		pr = &rr->power_rule;
1110

1111 1112
		/*
		 * We only need to know if one frequency rule was
1113
		 * was in center_freq's band, that's enough, so lets
1114 1115
		 * not overwrite it once found
		 */
1116 1117 1118
		if (!band_rule_found)
			band_rule_found = freq_in_rule_band(fr, center_freq);

1119 1120 1121
		bw_fits = reg_does_bw_fit(fr,
					  center_freq,
					  desired_bw_khz);
1122

1123
		if (band_rule_found && bw_fits) {
1124
			*reg_rule = rr;
1125
			return 0;
1126 1127 1128
		}
	}

1129 1130 1131
	if (!band_rule_found)
		return -ERANGE;

1132
	return -EINVAL;
1133
}
1134
EXPORT_SYMBOL(freq_reg_info);
1135

1136 1137 1138 1139
int freq_reg_info(struct wiphy *wiphy,
		  u32 center_freq,
		  u32 desired_bw_khz,
		  const struct ieee80211_reg_rule **reg_rule)
1140
{
1141
	assert_cfg80211_lock();
1142 1143 1144 1145 1146
	return freq_reg_info_regd(wiphy,
				  center_freq,
				  desired_bw_khz,
				  reg_rule,
				  NULL);
1147
}
1148

1149 1150 1151 1152 1153 1154 1155 1156 1157
/*
 * 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.
 */
1158 1159
static void handle_channel(struct wiphy *wiphy, enum ieee80211_band band,
			   unsigned int chan_idx)
1160 1161
{
	int r;
1162 1163
	u32 flags, bw_flags = 0;
	u32 desired_bw_khz = MHZ_TO_KHZ(20);
1164 1165
	const struct ieee80211_reg_rule *reg_rule = NULL;
	const struct ieee80211_power_rule *power_rule = NULL;
1166
	const struct ieee80211_freq_range *freq_range = NULL;
1167 1168
	struct ieee80211_supported_band *sband;
	struct ieee80211_channel *chan;
1169
	struct wiphy *request_wiphy = NULL;
1170

1171 1172
	assert_cfg80211_lock();

1173 1174
	request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);

1175 1176 1177 1178 1179
	sband = wiphy->bands[band];
	BUG_ON(chan_idx >= sband->n_channels);
	chan = &sband->channels[chan_idx];

	flags = chan->orig_flags;
1180

1181 1182 1183 1184
	r = freq_reg_info(wiphy,
			  MHZ_TO_KHZ(chan->center_freq),
			  desired_bw_khz,
			  &reg_rule);
1185 1186

	if (r) {
1187 1188
		/*
		 * This means no regulatory rule was found in the country IE
1189 1190 1191 1192 1193 1194 1195 1196 1197 1198
		 * 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 &&
1199 1200
		    last_request->initiator ==
		    NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1201
			REG_DBG_PRINT("cfg80211: Leaving channel %d MHz "
1202 1203
				"intact on %s - no rule found in band on "
				"Country IE\n",
1204
			chan->center_freq, wiphy_name(wiphy));
1205
		} else {
1206 1207 1208 1209
		/*
		 * In this case we know the country IE has at least one reg rule
		 * for the band so we respect its band definitions
		 */
1210 1211
			if (last_request->initiator ==
			    NL80211_REGDOM_SET_BY_COUNTRY_IE)
1212
				REG_DBG_PRINT("cfg80211: Disabling "
1213 1214 1215 1216 1217 1218
					"channel %d MHz on %s due to "
					"Country IE\n",
					chan->center_freq, wiphy_name(wiphy));
			flags |= IEEE80211_CHAN_DISABLED;
			chan->flags = flags;
		}
1219 1220 1221
		return;
	}

1222
	power_rule = &reg_rule->power_rule;
1223 1224 1225 1226
	freq_range = &reg_rule->freq_range;

	if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
		bw_flags = IEEE80211_CHAN_NO_HT40;
1227

1228
	if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1229
	    request_wiphy && request_wiphy == wiphy &&
J
Johannes Berg 已提交
1230
	    request_wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY) {
1231 1232
		/*
		 * This gaurantees the driver's requested regulatory domain
1233
		 * will always be used as a base for further regulatory
1234 1235
		 * settings
		 */
1236
		chan->flags = chan->orig_flags =
1237
			map_regdom_flags(reg_rule->flags) | bw_flags;
1238 1239 1240 1241 1242 1243 1244
		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;
	}

1245
	chan->flags = flags | bw_flags | map_regdom_flags(reg_rule->flags);
1246
	chan->max_antenna_gain = min(chan->orig_mag,
1247
		(int) MBI_TO_DBI(power_rule->max_antenna_gain));
1248
	if (chan->orig_mpwr)
1249 1250
		chan->max_power = min(chan->orig_mpwr,
			(int) MBM_TO_DBM(power_rule->max_eirp));
1251
	else
1252
		chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
1253 1254
}

1255
static void handle_band(struct wiphy *wiphy, enum ieee80211_band band)
1256
{
1257 1258 1259 1260 1261
	unsigned int i;
	struct ieee80211_supported_band *sband;

	BUG_ON(!wiphy->bands[band]);
	sband = wiphy->bands[band];
1262 1263

	for (i = 0; i < sband->n_channels; i++)
1264
		handle_channel(wiphy, band, i);
1265 1266
}

1267 1268
static bool ignore_reg_update(struct wiphy *wiphy,
			      enum nl80211_reg_initiator initiator)
1269 1270 1271
{
	if (!last_request)
		return true;
1272
	if (initiator == NL80211_REGDOM_SET_BY_CORE &&
J
Johannes Berg 已提交
1273
	    wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY)
1274
		return true;
1275 1276 1277 1278
	/*
	 * wiphy->regd will be set once the device has its own
	 * desired regulatory domain set
	 */
J
Johannes Berg 已提交
1279
	if (wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY && !wiphy->regd &&
1280
	    !is_world_regdom(last_request->alpha2))
1281 1282 1283 1284
		return true;
	return false;
}

1285
static void update_all_wiphy_regulatory(enum nl80211_reg_initiator initiator)
1286
{
1287
	struct cfg80211_registered_device *rdev;
1288

1289 1290
	list_for_each_entry(rdev, &cfg80211_rdev_list, list)
		wiphy_update_regulatory(&rdev->wiphy, initiator);
1291 1292
}

1293 1294 1295 1296 1297 1298
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;
1299 1300
	bool channel_changed = false;
	struct ieee80211_channel chan_before;
1301 1302 1303 1304 1305 1306 1307 1308 1309

	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;

1310 1311 1312 1313 1314
	if (chan->beacon_found)
		return;

	chan->beacon_found = true;

J
Johannes Berg 已提交
1315
	if (wiphy->flags & WIPHY_FLAG_DISABLE_BEACON_HINTS)
1316 1317
		return;

1318 1319 1320
	chan_before.center_freq = chan->center_freq;
	chan_before.flags = chan->flags;

1321
	if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN) {
1322
		chan->flags &= ~IEEE80211_CHAN_PASSIVE_SCAN;
1323
		channel_changed = true;
1324 1325
	}

1326
	if (chan->flags & IEEE80211_CHAN_NO_IBSS) {
1327
		chan->flags &= ~IEEE80211_CHAN_NO_IBSS;
1328
		channel_changed = true;
1329 1330
	}

1331 1332
	if (channel_changed)
		nl80211_send_beacon_hint_event(wiphy, &chan_before, chan);
1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383
}

/*
 * 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(&reg_beacon_list))
		return;

	list_for_each_entry(reg_beacon, &reg_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;
1384 1385
	if (last_request &&
	    last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
J
Johannes Berg 已提交
1386
	    wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY)
1387 1388 1389 1390 1391 1392 1393
		return true;
	return false;
}

/* Reap the advantages of previously found beacons */
static void reg_process_beacons(struct wiphy *wiphy)
{
1394 1395 1396 1397 1398 1399
	/*
	 * Means we are just firing up cfg80211, so no beacons would
	 * have been processed yet.
	 */
	if (!last_request)
		return;
1400 1401 1402 1403 1404
	if (!reg_is_world_roaming(wiphy))
		return;
	wiphy_update_beacon_reg(wiphy);
}

1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454
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))
1455
		channel->flags |= IEEE80211_CHAN_NO_HT40MINUS;
1456
	else
1457
		channel->flags &= ~IEEE80211_CHAN_NO_HT40MINUS;
1458 1459

	if (is_ht40_not_allowed(channel_after))
1460
		channel->flags |= IEEE80211_CHAN_NO_HT40PLUS;
1461
	else
1462
		channel->flags &= ~IEEE80211_CHAN_NO_HT40PLUS;
1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491
}

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);
	}

}

1492 1493
void wiphy_update_regulatory(struct wiphy *wiphy,
			     enum nl80211_reg_initiator initiator)
1494 1495
{
	enum ieee80211_band band;
1496

1497
	if (ignore_reg_update(wiphy, initiator))
1498
		goto out;
1499
	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1500
		if (wiphy->bands[band])
1501
			handle_band(wiphy, band);
1502
	}
1503 1504
out:
	reg_process_beacons(wiphy);
1505
	reg_process_ht_flags(wiphy);
1506
	if (wiphy->reg_notifier)
1507
		wiphy->reg_notifier(wiphy, last_request);
1508 1509
}

1510 1511 1512 1513 1514 1515
static void handle_channel_custom(struct wiphy *wiphy,
				  enum ieee80211_band band,
				  unsigned int chan_idx,
				  const struct ieee80211_regdomain *regd)
{
	int r;
1516 1517
	u32 desired_bw_khz = MHZ_TO_KHZ(20);
	u32 bw_flags = 0;
1518 1519
	const struct ieee80211_reg_rule *reg_rule = NULL;
	const struct ieee80211_power_rule *power_rule = NULL;
1520
	const struct ieee80211_freq_range *freq_range = NULL;
1521 1522 1523
	struct ieee80211_supported_band *sband;
	struct ieee80211_channel *chan;

1524
	assert_reg_lock();
1525

1526 1527 1528 1529
	sband = wiphy->bands[band];
	BUG_ON(chan_idx >= sband->n_channels);
	chan = &sband->channels[chan_idx];

1530 1531 1532 1533 1534
	r = freq_reg_info_regd(wiphy,
			       MHZ_TO_KHZ(chan->center_freq),
			       desired_bw_khz,
			       &reg_rule,
			       regd);
1535 1536 1537 1538 1539 1540 1541

	if (r) {
		chan->flags = IEEE80211_CHAN_DISABLED;
		return;
	}

	power_rule = &reg_rule->power_rule;
1542 1543 1544 1545
	freq_range = &reg_rule->freq_range;

	if (freq_range->max_bandwidth_khz < MHZ_TO_KHZ(40))
		bw_flags = IEEE80211_CHAN_NO_HT40;
1546

1547
	chan->flags |= map_regdom_flags(reg_rule->flags) | bw_flags;
1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569
	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;
1570
	unsigned int bands_set = 0;
1571

1572
	mutex_lock(&reg_mutex);
1573
	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
1574 1575 1576 1577
		if (!wiphy->bands[band])
			continue;
		handle_band_custom(wiphy, band, regd);
		bands_set++;
1578
	}
1579
	mutex_unlock(&reg_mutex);
1580 1581 1582 1583 1584 1585

	/*
	 * no point in calling this if it won't have any effect
	 * on your device's supportd bands.
	 */
	WARN_ON(!bands_set);
1586
}
1587 1588
EXPORT_SYMBOL(wiphy_apply_custom_regulatory);

1589 1590 1591 1592
/*
 * Return value which can be used by ignore_request() to indicate
 * it has been determined we should intersect two regulatory domains
 */
1593 1594
#define REG_INTERSECT	1

1595 1596
/* This has the logic which determines when a new request
 * should be ignored. */
1597 1598
static int ignore_request(struct wiphy *wiphy,
			  struct regulatory_request *pending_request)
1599
{
1600
	struct wiphy *last_wiphy = NULL;
1601 1602 1603

	assert_cfg80211_lock();

1604 1605 1606 1607
	/* All initial requests are respected */
	if (!last_request)
		return 0;

1608
	switch (pending_request->initiator) {
1609
	case NL80211_REGDOM_SET_BY_CORE:
1610
		return -EINVAL;
1611
	case NL80211_REGDOM_SET_BY_COUNTRY_IE:
1612 1613 1614

		last_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);

1615
		if (unlikely(!is_an_alpha2(pending_request->alpha2)))
1616
			return -EINVAL;
1617 1618
		if (last_request->initiator ==
		    NL80211_REGDOM_SET_BY_COUNTRY_IE) {
1619
			if (last_wiphy != wiphy) {
1620 1621
				/*
				 * Two cards with two APs claiming different
1622
				 * Country IE alpha2s. We could
1623 1624 1625
				 * intersect them, but that seems unlikely
				 * to be correct. Reject second one for now.
				 */
1626
				if (regdom_changes(pending_request->alpha2))
1627 1628 1629
					return -EOPNOTSUPP;
				return -EALREADY;
			}
1630 1631 1632 1633
			/*
			 * Two consecutive Country IE hints on the same wiphy.
			 * This should be picked up early by the driver/stack
			 */
1634
			if (WARN_ON(regdom_changes(pending_request->alpha2)))
1635 1636 1637
				return 0;
			return -EALREADY;
		}
1638
		return REG_INTERSECT;
1639 1640
	case NL80211_REGDOM_SET_BY_DRIVER:
		if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE) {
1641
			if (regdom_changes(pending_request->alpha2))
1642
				return 0;
1643
			return -EALREADY;
1644
		}
1645 1646 1647 1648 1649 1650

		/*
		 * 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.
		 */
1651
		if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1652
		    !regdom_changes(pending_request->alpha2))
1653 1654
			return -EALREADY;

1655
		return REG_INTERSECT;
1656 1657
	case NL80211_REGDOM_SET_BY_USER:
		if (last_request->initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE)
1658
			return REG_INTERSECT;
1659 1660 1661 1662
		/*
		 * If the user knows better the user should set the regdom
		 * to their country before the IE is picked up
		 */
1663
		if (last_request->initiator == NL80211_REGDOM_SET_BY_USER &&
1664 1665
			  last_request->intersect)
			return -EOPNOTSUPP;
1666 1667 1668 1669
		/*
		 * Process user requests only after previous user/driver/core
		 * requests have been processed
		 */
1670 1671 1672
		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) {
1673
			if (regdom_changes(last_request->alpha2))
1674 1675 1676
				return -EAGAIN;
		}

1677
		if (!regdom_changes(pending_request->alpha2))
1678 1679
			return -EALREADY;

1680 1681 1682 1683 1684 1685
		return 0;
	}

	return -EINVAL;
}

1686 1687 1688 1689
/**
 * __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
1690
 * @pending_request: the regulatory request currently being processed
1691 1692
 *
 * The Wireless subsystem can use this function to hint to the wireless core
1693
 * what it believes should be the current regulatory domain.
1694 1695 1696 1697
 *
 * Returns zero if all went fine, %-EALREADY if a regulatory domain had
 * already been set or other standard error codes.
 *
1698
 * Caller must hold &cfg80211_mutex and &reg_mutex
1699
 */
1700 1701
static int __regulatory_hint(struct wiphy *wiphy,
			     struct regulatory_request *pending_request)
1702
{
1703
	bool intersect = false;
1704 1705
	int r = 0;

1706 1707
	assert_cfg80211_lock();

1708
	r = ignore_request(wiphy, pending_request);
1709

1710
	if (r == REG_INTERSECT) {
1711 1712
		if (pending_request->initiator ==
		    NL80211_REGDOM_SET_BY_DRIVER) {
1713
			r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1714 1715
			if (r) {
				kfree(pending_request);
1716
				return r;
1717
			}
1718
		}
1719
		intersect = true;
1720
	} else if (r) {
1721 1722
		/*
		 * If the regulatory domain being requested by the
1723
		 * driver has already been set just copy it to the
1724 1725
		 * wiphy
		 */
1726
		if (r == -EALREADY &&
1727 1728
		    pending_request->initiator ==
		    NL80211_REGDOM_SET_BY_DRIVER) {
1729
			r = reg_copy_regd(&wiphy->regd, cfg80211_regdomain);
1730 1731
			if (r) {
				kfree(pending_request);
1732
				return r;
1733
			}
1734 1735 1736
			r = -EALREADY;
			goto new_request;
		}
1737
		kfree(pending_request);
1738
		return r;
1739
	}
1740

1741
new_request:
1742
	kfree(last_request);
1743

1744 1745
	last_request = pending_request;
	last_request->intersect = intersect;
1746

1747
	pending_request = NULL;
1748 1749

	/* When r == REG_INTERSECT we do need to call CRDA */
1750 1751 1752 1753 1754 1755 1756 1757
	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);
1758
		return r;
1759
	}
1760

1761
	return call_crda(last_request->alpha2);
1762 1763
}

1764
/* This processes *all* regulatory hints */
1765
static void reg_process_hint(struct regulatory_request *reg_request)
1766 1767 1768 1769 1770 1771 1772
{
	int r = 0;
	struct wiphy *wiphy = NULL;

	BUG_ON(!reg_request->alpha2);

	mutex_lock(&cfg80211_mutex);
1773
	mutex_lock(&reg_mutex);
1774 1775 1776 1777

	if (wiphy_idx_valid(reg_request->wiphy_idx))
		wiphy = wiphy_idx_to_wiphy(reg_request->wiphy_idx);

1778
	if (reg_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
1779
	    !wiphy) {
1780
		kfree(reg_request);
1781 1782 1783
		goto out;
	}

1784
	r = __regulatory_hint(wiphy, reg_request);
1785
	/* This is required so that the orig_* parameters are saved */
J
Johannes Berg 已提交
1786 1787
	if (r == -EALREADY && wiphy &&
	    wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY)
1788 1789
		wiphy_update_regulatory(wiphy, reg_request->initiator);
out:
1790
	mutex_unlock(&reg_mutex);
1791 1792 1793
	mutex_unlock(&cfg80211_mutex);
}

1794
/* Processes regulatory hints, this is all the NL80211_REGDOM_SET_BY_* */
1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805
static void reg_process_pending_hints(void)
	{
	struct regulatory_request *reg_request;

	spin_lock(&reg_requests_lock);
	while (!list_empty(&reg_requests_list)) {
		reg_request = list_first_entry(&reg_requests_list,
					       struct regulatory_request,
					       list);
		list_del_init(&reg_request->list);

1806 1807
		spin_unlock(&reg_requests_lock);
		reg_process_hint(reg_request);
1808 1809 1810 1811 1812
		spin_lock(&reg_requests_lock);
	}
	spin_unlock(&reg_requests_lock);
}

1813 1814 1815
/* Processes beacon hints -- this has nothing to do with country IEs */
static void reg_process_pending_beacon_hints(void)
{
1816
	struct cfg80211_registered_device *rdev;
1817 1818
	struct reg_beacon *pending_beacon, *tmp;

1819 1820 1821 1822
	/*
	 * No need to hold the reg_mutex here as we just touch wiphys
	 * and do not read or access regulatory variables.
	 */
1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838
	mutex_lock(&cfg80211_mutex);

	/* This goes through the _pending_ beacon list */
	spin_lock_bh(&reg_pending_beacons_lock);

	if (list_empty(&reg_pending_beacons)) {
		spin_unlock_bh(&reg_pending_beacons_lock);
		goto out;
	}

	list_for_each_entry_safe(pending_beacon, tmp,
				 &reg_pending_beacons, list) {

		list_del_init(&pending_beacon->list);

		/* Applies the beacon hint to current wiphys */
1839 1840
		list_for_each_entry(rdev, &cfg80211_rdev_list, list)
			wiphy_update_new_beacon(&rdev->wiphy, pending_beacon);
1841 1842 1843 1844 1845 1846 1847 1848 1849 1850

		/* Remembers the beacon hint for new wiphys or reg changes */
		list_add_tail(&pending_beacon->list, &reg_beacon_list);
	}

	spin_unlock_bh(&reg_pending_beacons_lock);
out:
	mutex_unlock(&cfg80211_mutex);
}

1851 1852 1853
static void reg_todo(struct work_struct *work)
{
	reg_process_pending_hints();
1854
	reg_process_pending_beacon_hints();
1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868
}

static DECLARE_WORK(reg_work, reg_todo);

static void queue_regulatory_request(struct regulatory_request *request)
{
	spin_lock(&reg_requests_lock);
	list_add_tail(&request->list, &reg_requests_list);
	spin_unlock(&reg_requests_lock);

	schedule_work(&reg_work);
}

/* Core regulatory hint -- happens once during cfg80211_init() */
1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881
static int regulatory_hint_core(const char *alpha2)
{
	struct regulatory_request *request;

	BUG_ON(last_request);

	request = kzalloc(sizeof(struct regulatory_request),
			  GFP_KERNEL);
	if (!request)
		return -ENOMEM;

	request->alpha2[0] = alpha2[0];
	request->alpha2[1] = alpha2[1];
1882
	request->initiator = NL80211_REGDOM_SET_BY_CORE;
1883

1884
	queue_regulatory_request(request);
1885

1886 1887 1888 1889 1890 1891 1892
	/*
	 * This ensures last_request is populated once modules
	 * come swinging in and calling regulatory hints and
	 * wiphy_apply_custom_regulatory().
	 */
	flush_scheduled_work();

1893
	return 0;
1894 1895
}

1896 1897
/* User hints */
int regulatory_hint_user(const char *alpha2)
1898
{
1899 1900
	struct regulatory_request *request;

1901
	BUG_ON(!alpha2);
1902

1903 1904 1905 1906 1907 1908 1909
	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];
1910
	request->initiator = NL80211_REGDOM_SET_BY_USER;
1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935

	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];
1936
	request->initiator = NL80211_REGDOM_SET_BY_DRIVER;
1937 1938 1939 1940

	queue_regulatory_request(request);

	return 0;
1941 1942 1943
}
EXPORT_SYMBOL(regulatory_hint);

1944
/* Caller must hold reg_mutex */
1945 1946 1947
static bool reg_same_country_ie_hint(struct wiphy *wiphy,
			u32 country_ie_checksum)
{
1948 1949
	struct wiphy *request_wiphy;

1950
	assert_reg_lock();
1951

1952 1953 1954 1955
	if (unlikely(last_request->initiator !=
	    NL80211_REGDOM_SET_BY_COUNTRY_IE))
		return false;

1956 1957 1958
	request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);

	if (!request_wiphy)
1959
		return false;
1960 1961

	if (likely(request_wiphy != wiphy))
1962
		return !country_ie_integrity_changes(country_ie_checksum);
1963 1964
	/*
	 * We should not have let these through at this point, they
1965
	 * should have been picked up earlier by the first alpha2 check
1966 1967
	 * on the device
	 */
1968 1969 1970 1971 1972
	if (WARN_ON(!country_ie_integrity_changes(country_ie_checksum)))
		return true;
	return false;
}

1973 1974 1975 1976
/*
 * We hold wdev_lock() here so we cannot hold cfg80211_mutex() and
 * therefore cannot iterate over the rdev list here.
 */
1977 1978 1979 1980 1981 1982 1983 1984
void regulatory_hint_11d(struct wiphy *wiphy,
			u8 *country_ie,
			u8 country_ie_len)
{
	struct ieee80211_regdomain *rd = NULL;
	char alpha2[2];
	u32 checksum = 0;
	enum environment_cap env = ENVIRON_ANY;
1985
	struct regulatory_request *request;
1986

1987
	mutex_lock(&reg_mutex);
1988

1989 1990
	if (unlikely(!last_request))
		goto out;
1991

1992 1993 1994 1995 1996 1997 1998
	/* 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;

1999 2000
	/*
	 * Pending country IE processing, this can happen after we
2001
	 * call CRDA and wait for a response if a beacon was received before
2002 2003
	 * we were able to process the last regulatory_hint_11d() call
	 */
2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014
	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;

2015
	/*
2016
	 * We will run this only upon a successful connection on cfg80211.
2017 2018
	 * We leave conflict resolution to the workqueue, where can hold
	 * cfg80211_mutex.
2019
	 */
2020 2021
	if (likely(last_request->initiator ==
	    NL80211_REGDOM_SET_BY_COUNTRY_IE &&
2022 2023
	    wiphy_idx_valid(last_request->wiphy_idx)))
		goto out;
2024 2025

	rd = country_ie_2_rd(country_ie, country_ie_len, &checksum);
2026 2027
	if (!rd) {
		REG_DBG_PRINT("cfg80211: Ignoring bogus country IE\n");
2028
		goto out;
2029
	}
2030

2031 2032
	/*
	 * This will not happen right now but we leave it here for the
2033 2034
	 * 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
2035 2036 2037 2038 2039 2040
	 * 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)))
2041
		goto free_rd_out;
2042

2043 2044 2045 2046
	request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
	if (!request)
		goto free_rd_out;

2047 2048 2049 2050
	/*
	 * We keep this around for when CRDA comes back with a response so
	 * we can intersect with that
	 */
2051 2052
	country_ie_regdomain = rd;

2053 2054 2055
	request->wiphy_idx = get_wiphy_idx(wiphy);
	request->alpha2[0] = rd->alpha2[0];
	request->alpha2[1] = rd->alpha2[1];
2056
	request->initiator = NL80211_REGDOM_SET_BY_COUNTRY_IE;
2057 2058 2059
	request->country_ie_checksum = checksum;
	request->country_ie_env = env;

2060
	mutex_unlock(&reg_mutex);
2061

2062 2063 2064
	queue_regulatory_request(request);

	return;
2065 2066 2067

free_rd_out:
	kfree(rd);
2068
out:
2069
	mutex_unlock(&reg_mutex);
2070
}
2071

2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096
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;

2097 2098 2099 2100 2101 2102
	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));

2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119
	memcpy(&reg_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(&reg_pending_beacons_lock);
	list_add_tail(&reg_beacon->list, &reg_pending_beacons);
	spin_unlock_bh(&reg_pending_beacons_lock);

	schedule_work(&reg_work);

	return 0;
}

2120
static void print_rd_rules(const struct ieee80211_regdomain *rd)
2121 2122
{
	unsigned int i;
2123 2124 2125
	const struct ieee80211_reg_rule *reg_rule = NULL;
	const struct ieee80211_freq_range *freq_range = NULL;
	const struct ieee80211_power_rule *power_rule = NULL;
2126

2127
	printk(KERN_INFO "    (start_freq - end_freq @ bandwidth), "
2128 2129 2130 2131 2132 2133 2134
		"(max_antenna_gain, max_eirp)\n");

	for (i = 0; i < rd->n_reg_rules; i++) {
		reg_rule = &rd->reg_rules[i];
		freq_range = &reg_rule->freq_range;
		power_rule = &reg_rule->power_rule;

2135 2136 2137 2138
		/*
		 * There may not be documentation for max antenna gain
		 * in certain regions
		 */
2139
		if (power_rule->max_antenna_gain)
2140
			printk(KERN_INFO "    (%d KHz - %d KHz @ %d KHz), "
2141 2142 2143 2144 2145 2146 2147
				"(%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
2148
			printk(KERN_INFO "    (%d KHz - %d KHz @ %d KHz), "
2149 2150 2151 2152 2153 2154 2155 2156
				"(N/A, %d mBm)\n",
				freq_range->start_freq_khz,
				freq_range->end_freq_khz,
				freq_range->max_bandwidth_khz,
				power_rule->max_eirp);
	}
}

2157
static void print_regdomain(const struct ieee80211_regdomain *rd)
2158 2159
{

2160 2161
	if (is_intersected_alpha2(rd->alpha2)) {

2162 2163
		if (last_request->initiator ==
		    NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2164 2165
			struct cfg80211_registered_device *rdev;
			rdev = cfg80211_rdev_by_wiphy_idx(
2166
				last_request->wiphy_idx);
2167
			if (rdev) {
2168 2169
				printk(KERN_INFO "cfg80211: Current regulatory "
					"domain updated by AP to: %c%c\n",
2170 2171
					rdev->country_ie_alpha2[0],
					rdev->country_ie_alpha2[1]);
2172 2173 2174 2175 2176
			} else
				printk(KERN_INFO "cfg80211: Current regulatory "
					"domain intersected: \n");
		} else
				printk(KERN_INFO "cfg80211: Current regulatory "
2177
					"domain intersected: \n");
2178
	} else if (is_world_regdom(rd->alpha2))
2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193
		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);
}

2194
static void print_regdomain_info(const struct ieee80211_regdomain *rd)
2195 2196 2197 2198 2199 2200
{
	printk(KERN_INFO "cfg80211: Regulatory domain: %c%c\n",
		rd->alpha2[0], rd->alpha2[1]);
	print_rd_rules(rd);
}

2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213
#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");
2214
		print_regdomain_info(intersected_rd);
2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227
		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

2228
/* Takes ownership of rd only if it doesn't fail */
2229
static int __set_regdom(const struct ieee80211_regdomain *rd)
2230
{
2231
	const struct ieee80211_regdomain *intersected_rd = NULL;
2232
	struct cfg80211_registered_device *rdev = NULL;
2233
	struct wiphy *request_wiphy;
2234 2235 2236
	/* Some basic sanity checks first */

	if (is_world_regdom(rd->alpha2)) {
2237
		if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
2238 2239 2240 2241 2242 2243 2244 2245 2246
			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;

2247
	if (!last_request)
2248 2249
		return -EINVAL;

2250 2251
	/*
	 * Lets only bother proceeding on the same alpha2 if the current
2252
	 * rd is non static (it means CRDA was present and was used last)
2253 2254
	 * and the pending request came in from a country IE
	 */
2255
	if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2256 2257 2258 2259
		/*
		 * If someone else asked us to change the rd lets only bother
		 * checking if the alpha2 changes if CRDA was already called
		 */
2260
		if (!regdom_changes(rd->alpha2))
2261 2262 2263
			return -EINVAL;
	}

2264 2265
	/*
	 * Now lets set the regulatory domain, update all driver channels
2266 2267
	 * and finally inform them of what we have done, in case they want
	 * to review or adjust their own settings based on their own
2268 2269
	 * internal EEPROM data
	 */
2270

2271
	if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
2272 2273
		return -EINVAL;

2274 2275 2276 2277 2278
	if (!is_valid_rd(rd)) {
		printk(KERN_ERR "cfg80211: Invalid "
			"regulatory domain detected:\n");
		print_regdomain_info(rd);
		return -EINVAL;
2279 2280
	}

2281 2282
	request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);

2283
	if (!last_request->intersect) {
2284 2285
		int r;

2286
		if (last_request->initiator != NL80211_REGDOM_SET_BY_DRIVER) {
2287 2288 2289 2290 2291
			reset_regdomains();
			cfg80211_regdomain = rd;
			return 0;
		}

2292 2293 2294 2295
		/*
		 * For a driver hint, lets copy the regulatory domain the
		 * driver wanted to the wiphy to deal with conflicts
		 */
2296

2297 2298 2299 2300 2301 2302
		/*
		 * Userspace could have sent two replies with only
		 * one kernel request.
		 */
		if (request_wiphy->regd)
			return -EALREADY;
2303

2304
		r = reg_copy_regd(&request_wiphy->regd, rd);
2305 2306 2307
		if (r)
			return r;

2308 2309 2310 2311 2312 2313 2314
		reset_regdomains();
		cfg80211_regdomain = rd;
		return 0;
	}

	/* Intersection requires a bit more work */

2315
	if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
2316

2317 2318 2319
		intersected_rd = regdom_intersect(rd, cfg80211_regdomain);
		if (!intersected_rd)
			return -EINVAL;
2320

2321 2322
		/*
		 * We can trash what CRDA provided now.
2323
		 * However if a driver requested this specific regulatory
2324 2325
		 * domain we keep it for its private use
		 */
2326
		if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER)
2327
			request_wiphy->regd = rd;
2328 2329 2330
		else
			kfree(rd);

2331 2332 2333 2334 2335 2336
		rd = NULL;

		reset_regdomains();
		cfg80211_regdomain = intersected_rd;

		return 0;
2337 2338
	}

2339 2340 2341 2342 2343
	/*
	 * Country IE requests are handled a bit differently, we intersect
	 * the country IE rd with what CRDA believes that country should have
	 */

2344 2345 2346 2347 2348 2349 2350
	/*
	 * 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;
2351
	BUG_ON(rd == country_ie_regdomain);
2352

2353 2354 2355 2356
	/*
	 * Intersect what CRDA returned and our what we
	 * had built from the Country IE received
	 */
2357

2358
	intersected_rd = regdom_intersect(rd, country_ie_regdomain);
2359

2360 2361 2362
	reg_country_ie_process_debug(rd,
				     country_ie_regdomain,
				     intersected_rd);
2363

2364 2365
	kfree(country_ie_regdomain);
	country_ie_regdomain = NULL;
2366 2367 2368 2369

	if (!intersected_rd)
		return -EINVAL;

2370
	rdev = wiphy_to_dev(request_wiphy);
2371

2372 2373 2374
	rdev->country_ie_alpha2[0] = rd->alpha2[0];
	rdev->country_ie_alpha2[1] = rd->alpha2[1];
	rdev->env = last_request->country_ie_env;
2375 2376 2377 2378 2379 2380

	BUG_ON(intersected_rd == rd);

	kfree(rd);
	rd = NULL;

2381
	reset_regdomains();
2382
	cfg80211_regdomain = intersected_rd;
2383 2384 2385 2386 2387

	return 0;
}


2388 2389
/*
 * Use this call to set the current regulatory domain. Conflicts with
2390
 * multiple drivers can be ironed out later. Caller must've already
2391 2392
 * kmalloc'd the rd structure. Caller must hold cfg80211_mutex
 */
2393
int set_regdom(const struct ieee80211_regdomain *rd)
2394 2395 2396
{
	int r;

2397 2398
	assert_cfg80211_lock();

2399 2400
	mutex_lock(&reg_mutex);

2401 2402
	/* Note that this doesn't update the wiphys, this is done below */
	r = __set_regdom(rd);
2403 2404
	if (r) {
		kfree(rd);
2405
		mutex_unlock(&reg_mutex);
2406
		return r;
2407
	}
2408 2409

	/* This would make this whole thing pointless */
2410 2411
	if (!last_request->intersect)
		BUG_ON(rd != cfg80211_regdomain);
2412 2413

	/* update all wiphys now with the new established regulatory domain */
2414
	update_all_wiphy_regulatory(last_request->initiator);
2415

2416
	print_regdomain(cfg80211_regdomain);
2417

2418 2419
	nl80211_send_reg_change_event(last_request);

2420 2421
	mutex_unlock(&reg_mutex);

2422 2423 2424
	return r;
}

2425
/* Caller must hold cfg80211_mutex */
2426 2427
void reg_device_remove(struct wiphy *wiphy)
{
2428
	struct wiphy *request_wiphy = NULL;
2429

2430 2431
	assert_cfg80211_lock();

2432 2433
	mutex_lock(&reg_mutex);

2434 2435
	kfree(wiphy->regd);

2436 2437
	if (last_request)
		request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
2438

2439
	if (!request_wiphy || request_wiphy != wiphy)
2440
		goto out;
2441

2442
	last_request->wiphy_idx = WIPHY_IDX_STALE;
2443
	last_request->country_ie_env = ENVIRON_ANY;
2444 2445
out:
	mutex_unlock(&reg_mutex);
2446 2447
}

2448 2449
int regulatory_init(void)
{
2450
	int err = 0;
2451

2452 2453 2454
	reg_pdev = platform_device_register_simple("regulatory", 0, NULL, 0);
	if (IS_ERR(reg_pdev))
		return PTR_ERR(reg_pdev);
2455

2456
	spin_lock_init(&reg_requests_lock);
2457
	spin_lock_init(&reg_pending_beacons_lock);
2458

2459
	cfg80211_regdomain = cfg80211_world_regdom;
2460

2461 2462
	/* We always try to get an update for the static regdomain */
	err = regulatory_hint_core(cfg80211_regdomain->alpha2);
2463
	if (err) {
2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477
		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);
2478
#endif
2479
	}
2480

2481 2482 2483 2484 2485 2486 2487
	/*
	 * 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);

2488 2489 2490 2491 2492
	return 0;
}

void regulatory_exit(void)
{
2493
	struct regulatory_request *reg_request, *tmp;
2494
	struct reg_beacon *reg_beacon, *btmp;
2495 2496 2497

	cancel_work_sync(&reg_work);

2498
	mutex_lock(&cfg80211_mutex);
2499
	mutex_lock(&reg_mutex);
2500

2501
	reset_regdomains();
2502

2503 2504 2505
	kfree(country_ie_regdomain);
	country_ie_regdomain = NULL;

2506 2507
	kfree(last_request);

2508
	platform_device_unregister(reg_pdev);
2509

2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527
	spin_lock_bh(&reg_pending_beacons_lock);
	if (!list_empty(&reg_pending_beacons)) {
		list_for_each_entry_safe(reg_beacon, btmp,
					 &reg_pending_beacons, list) {
			list_del(&reg_beacon->list);
			kfree(reg_beacon);
		}
	}
	spin_unlock_bh(&reg_pending_beacons_lock);

	if (!list_empty(&reg_beacon_list)) {
		list_for_each_entry_safe(reg_beacon, btmp,
					 &reg_beacon_list, list) {
			list_del(&reg_beacon->list);
			kfree(reg_beacon);
		}
	}

2528 2529 2530 2531 2532 2533 2534 2535 2536 2537
	spin_lock(&reg_requests_lock);
	if (!list_empty(&reg_requests_list)) {
		list_for_each_entry_safe(reg_request, tmp,
					 &reg_requests_list, list) {
			list_del(&reg_request->list);
			kfree(reg_request);
		}
	}
	spin_unlock(&reg_requests_lock);

2538
	mutex_unlock(&reg_mutex);
2539
	mutex_unlock(&cfg80211_mutex);
2540
}