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linux/net/wireless/reg.c
Lucas De Marchi 25985edced Fix common misspellings 
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00

2222 lines
57 KiB
C
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/*
* 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.
*
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/random.h>
#include <linux/ctype.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 pr_fmt(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;
static struct device_type reg_device_type = {
.uevent = reg_device_uevent,
};
/*
* 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;
/*
* Protects static reg.c components:
* - cfg80211_world_regdom
* - cfg80211_regdom
* - last_request
*/
static DEFINE_MUTEX(reg_mutex);
static inline void assert_reg_lock(void)
{
lockdep_assert_held(&reg_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;
};
static void reg_todo(struct work_struct *work);
static DECLARE_WORK(reg_work, reg_todo);
/* 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_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 (isalpha(alpha2[0]) && isalpha(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;
}
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_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(&reg_regdb_search_mutex);
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;
mutex_lock(&cfg80211_mutex);
set_regdom(regdom);
mutex_unlock(&cfg80211_mutex);
break;
}
}
kfree(request);
}
mutex_unlock(&reg_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(&reg_regdb_search_mutex);
list_add_tail(&request->list, &reg_regdb_search_list);
mutex_unlock(&reg_regdb_search_mutex);
schedule_work(&reg_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. Country information is filled in by
* reg_device_uevent
*/
static int call_crda(const char *alpha2)
{
if (!is_world_regdom((char *) alpha2))
pr_info("Calling CRDA for country: %c%c\n",
alpha2[0], alpha2[1]);
else
pr_info("Calling CRDA to update world regulatory domain\n");
/* query internal regulatory database (if it exists) */
reg_regdb_query(alpha2);
return kobject_uevent(&reg_pdev->dev.kobj, KOBJ_CHANGE);
}
/* 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
}
/*
* 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 (!custom_regd &&
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 = &regd->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;
}
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);
}
EXPORT_SYMBOL(freq_reg_info);
#ifdef CONFIG_CFG80211_REG_DEBUG
static const char *reg_initiator_name(enum nl80211_reg_initiator initiator)
{
switch (initiator) {
case NL80211_REGDOM_SET_BY_CORE:
return "Set by core";
case NL80211_REGDOM_SET_BY_USER:
return "Set by user";
case NL80211_REGDOM_SET_BY_DRIVER:
return "Set by driver";
case NL80211_REGDOM_SET_BY_COUNTRY_IE:
return "Set by country IE";
default:
WARN_ON(1);
return "Set by bug";
}
}
static void chan_reg_rule_print_dbg(struct ieee80211_channel *chan,
u32 desired_bw_khz,
const struct ieee80211_reg_rule *reg_rule)
{
const struct ieee80211_power_rule *power_rule;
const struct ieee80211_freq_range *freq_range;
char max_antenna_gain[32];
power_rule = &reg_rule->power_rule;
freq_range = &reg_rule->freq_range;
if (!power_rule->max_antenna_gain)
snprintf(max_antenna_gain, 32, "N/A");
else
snprintf(max_antenna_gain, 32, "%d", power_rule->max_antenna_gain);
REG_DBG_PRINT("Updating information on frequency %d MHz "
"for a %d MHz width channel with regulatory rule:\n",
chan->center_freq,
KHZ_TO_MHZ(desired_bw_khz));
REG_DBG_PRINT("%d KHz - %d KHz @ KHz), (%s mBi, %d mBm)\n",
freq_range->start_freq_khz,
freq_range->end_freq_khz,
max_antenna_gain,
power_rule->max_eirp);
}
#else
static void chan_reg_rule_print_dbg(struct ieee80211_channel *chan,
u32 desired_bw_khz,
const struct ieee80211_reg_rule *reg_rule)
{
return;
}
#endif
/*
* 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 nl80211_reg_initiator initiator,
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,
&reg_rule);
if (r) {
/*
* We will disable all channels that do not match our
* received regulatory rule unless the hint is coming
* from a Country IE and the Country IE had no information
* about a band. The IEEE 802.11 spec allows for an AP
* to send only a subset of the regulatory rules allowed,
* so an AP in the US that only supports 2.4 GHz may only send
* a country IE with information for the 2.4 GHz band
* while 5 GHz is still supported.
*/
if (initiator == NL80211_REGDOM_SET_BY_COUNTRY_IE &&
r == -ERANGE)
return;
REG_DBG_PRINT("Disabling freq %d MHz\n", chan->center_freq);
chan->flags = IEEE80211_CHAN_DISABLED;
return;
}
chan_reg_rule_print_dbg(chan, desired_bw_khz, reg_rule);
power_rule = &reg_rule->power_rule;
freq_range = &reg_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 guarantees 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,
enum nl80211_reg_initiator initiator)
{
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, initiator, band, i);
}
static bool ignore_reg_update(struct wiphy *wiphy,
enum nl80211_reg_initiator initiator)
{
if (!last_request) {
REG_DBG_PRINT("Ignoring regulatory request %s since "
"last_request is not set\n",
reg_initiator_name(initiator));
return true;
}
if (initiator == NL80211_REGDOM_SET_BY_CORE &&
wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY) {
REG_DBG_PRINT("Ignoring regulatory request %s "
"since the driver uses its own custom "
"regulatory domain ",
reg_initiator_name(initiator));
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 &&
initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
!is_world_regdom(last_request->alpha2)) {
REG_DBG_PRINT("Ignoring regulatory request %s "
"since the driver requires its own regulaotry "
"domain to be set first",
reg_initiator_name(initiator));
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(&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;
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, initiator);
}
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,
&reg_rule,
regd);
if (r) {
REG_DBG_PRINT("Disabling freq %d MHz as custom "
"regd has no rule that fits a %d MHz "
"wide channel\n",
chan->center_freq,
KHZ_TO_MHZ(desired_bw_khz));
chan->flags = IEEE80211_CHAN_DISABLED;
return;
}
chan_reg_rule_print_dbg(chan, desired_bw_khz, reg_rule);
power_rule = &reg_rule->power_rule;
freq_range = &reg_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(&reg_mutex);
for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
if (!wiphy->bands[band])
continue;
handle_band_custom(wiphy, band, regd);
bands_set++;
}
mutex_unlock(&reg_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 0;
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;
}
static void reg_set_request_processed(void)
{
bool need_more_processing = false;
last_request->processed = true;
spin_lock(&reg_requests_lock);
if (!list_empty(&reg_requests_list))
need_more_processing = true;
spin_unlock(&reg_requests_lock);
if (need_more_processing)
schedule_work(&reg_work);
}
/**
* __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 &reg_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);
reg_set_request_processed();
}
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;
enum nl80211_reg_initiator initiator = reg_request->initiator;
BUG_ON(!reg_request->alpha2);
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);
return;
}
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, initiator);
}
/*
* Processes regulatory hints, this is all the NL80211_REGDOM_SET_BY_*
* Regulatory hints come on a first come first serve basis and we
* must process each one atomically.
*/
static void reg_process_pending_hints(void)
{
struct regulatory_request *reg_request;
mutex_lock(&cfg80211_mutex);
mutex_lock(&reg_mutex);
/* When last_request->processed becomes true this will be rescheduled */
if (last_request && !last_request->processed) {
REG_DBG_PRINT("Pending regulatory request, waiting "
"for it to be processed...");
goto out;
}
spin_lock(&reg_requests_lock);
if (list_empty(&reg_requests_list)) {
spin_unlock(&reg_requests_lock);
goto out;
}
reg_request = list_first_entry(&reg_requests_list,
struct regulatory_request,
list);
list_del_init(&reg_request->list);
spin_unlock(&reg_requests_lock);
reg_process_hint(reg_request);
out:
mutex_unlock(&reg_mutex);
mutex_unlock(&cfg80211_mutex);
}
/* 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(&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 */
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, &reg_beacon_list);
}
spin_unlock_bh(&reg_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 void queue_regulatory_request(struct regulatory_request *request)
{
if (isalpha(request->alpha2[0]))
request->alpha2[0] = toupper(request->alpha2[0]);
if (isalpha(request->alpha2[1]))
request->alpha2[1] = toupper(request->alpha2[1]);
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 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;
queue_regulatory_request(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);
/*
* 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)
{
char alpha2[2];
enum environment_cap env = ENVIRON_ANY;
struct regulatory_request *request;
mutex_lock(&reg_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;
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;
request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
if (!request)
goto out;
request->wiphy_idx = get_wiphy_idx(wiphy);
request->alpha2[0] = alpha2[0];
request->alpha2[1] = alpha2[1];
request->initiator = NL80211_REGDOM_SET_BY_COUNTRY_IE;
request->country_ie_env = env;
mutex_unlock(&reg_mutex);
queue_regulatory_request(request);
return;
out:
mutex_unlock(&reg_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("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("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("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("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("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(&reg_mutex);
reset_regdomains();
restore_alpha2(alpha2, reset_user);
/* Clear beacon hints */
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);
}
}
/* First restore to the basic regulatory settings */
cfg80211_regdomain = cfg80211_world_regdom;
mutex_unlock(&reg_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("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, IEEE80211_BAND_2GHZ) ||
freq == ieee80211_channel_to_frequency(13, IEEE80211_BAND_2GHZ) ||
freq == ieee80211_channel_to_frequency(14, IEEE80211_BAND_2GHZ))
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("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(&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;
}
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;
pr_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 = &reg_rule->freq_range;
power_rule = &reg_rule->power_rule;
/*
* There may not be documentation for max antenna gain
* in certain regions
*/
if (power_rule->max_antenna_gain)
pr_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
pr_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) {
pr_info("Current regulatory domain updated by AP to: %c%c\n",
rdev->country_ie_alpha2[0],
rdev->country_ie_alpha2[1]);
} else
pr_info("Current regulatory domain intersected:\n");
} else
pr_info("Current regulatory domain intersected:\n");
} else if (is_world_regdom(rd->alpha2))
pr_info("World regulatory domain updated:\n");
else {
if (is_unknown_alpha2(rd->alpha2))
pr_info("Regulatory domain changed to driver built-in settings (unknown country)\n");
else
pr_info("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)
{
pr_info("Regulatory domain: %c%c\n", rd->alpha2[0], rd->alpha2[1]);
print_rd_rules(rd);
}
/* 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)) {
pr_err("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;
}
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(&reg_mutex);
/* Note that this doesn't update the wiphys, this is done below */
r = __set_regdom(rd);
if (r) {
kfree(rd);
mutex_unlock(&reg_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);
reg_set_request_processed();
mutex_unlock(&reg_mutex);
return r;
}
#ifdef CONFIG_HOTPLUG
int reg_device_uevent(struct device *dev, struct kobj_uevent_env *env)
{
if (last_request && !last_request->processed) {
if (add_uevent_var(env, "COUNTRY=%c%c",
last_request->alpha2[0],
last_request->alpha2[1]))
return -ENOMEM;
}
return 0;
}
#else
int reg_device_uevent(struct device *dev, struct kobj_uevent_env *env)
{
return -ENODEV;
}
#endif /* CONFIG_HOTPLUG */
/* Caller must hold cfg80211_mutex */
void reg_device_remove(struct wiphy *wiphy)
{
struct wiphy *request_wiphy = NULL;
assert_cfg80211_lock();
mutex_lock(&reg_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(&reg_mutex);
}
int __init 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);
reg_pdev->dev.type = &reg_device_type;
spin_lock_init(&reg_requests_lock);
spin_lock_init(&reg_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.
*/
pr_err("kobject_uevent_env() was unable to call CRDA during init\n");
#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 /* __init_or_exit */ regulatory_exit(void)
{
struct regulatory_request *reg_request, *tmp;
struct reg_beacon *reg_beacon, *btmp;
cancel_work_sync(&reg_work);
mutex_lock(&cfg80211_mutex);
mutex_lock(&reg_mutex);
reset_regdomains();
kfree(last_request);
platform_device_unregister(reg_pdev);
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);
}
}
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);
mutex_unlock(&reg_mutex);
mutex_unlock(&cfg80211_mutex);
}
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