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reg.c
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/*
* Copyright 2002-2005, Instant802 Networks, Inc.
* Copyright 2005-2006, Devicescape Software, Inc.
* Copyright 2007 Johannes Berg <[email protected]>
* Copyright 2008 Luis R. Rodriguez <[email protected]>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
/**
* DOC: Wireless regulatory infrastructure
*
* The usual implementation is for a driver to read a device EEPROM to
* determine which regulatory domain it should be operating under, then
* looking up the allowable channels in a driver-local table and finally
* registering those channels in the wiphy structure.
*
* Another set of compliance enforcement is for drivers to use their
* own compliance limits which can be stored on the EEPROM. The host
* driver or firmware may ensure these are used.
*
* In addition to all this we provide an extra layer of regulatory
* conformance. For drivers which do not have any regulatory
* information CRDA provides the complete regulatory solution.
* For others it provides a community effort on further restrictions
* to enhance compliance.
*
* Note: When number of rules --> infinity we will not be able to
* index on alpha2 any more, instead we'll probably have to
* rely on some SHA1 checksum of the regdomain for example.
*
*/
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/random.h>
#include <linux/nl80211.h>
#include <linux/platform_device.h>
#include <net/wireless.h>
#include <net/cfg80211.h>
#include "core.h"
#include "reg.h"
#include "nl80211.h"
/* Receipt of information from last regulatory request */
static struct regulatory_request *last_request;
/* To trigger userspace events */
static struct platform_device *reg_pdev;
/* Keep the ordering from large to small */
static u32 supported_bandwidths[] = {
MHZ_TO_KHZ(40),
MHZ_TO_KHZ(20),
};
/*
* Central wireless core regulatory domains, we only need two,
* the current one and a world regulatory domain in case we have no
* information to give us an alpha2
*/
const struct ieee80211_regdomain *cfg80211_regdomain;
/*
* We use this as a place for the rd structure built from the
* last parsed country IE to rest until CRDA gets back to us with
* what it thinks should apply for the same country
*/
static const struct ieee80211_regdomain *country_ie_regdomain;
/* Used to queue up regulatory hints */
static LIST_HEAD(reg_requests_list);
static spinlock_t reg_requests_lock;
/* Used to queue up beacon hints for review */
static LIST_HEAD(reg_pending_beacons);
static spinlock_t reg_pending_beacons_lock;
/* Used to keep track of processed beacon hints */
static LIST_HEAD(reg_beacon_list);
struct reg_beacon {
struct list_head list;
struct ieee80211_channel chan;
};
/* We keep a static world regulatory domain in case of the absence of CRDA */
static const struct ieee80211_regdomain world_regdom = {
.n_reg_rules = 5,
.alpha2 = "00",
.reg_rules = {
/* IEEE 802.11b/g, channels 1..11 */
REG_RULE(2412-10, 2462+10, 40, 6, 20, 0),
/* IEEE 802.11b/g, channels 12..13. No HT40
* channel fits here. */
REG_RULE(2467-10, 2472+10, 20, 6, 20,
NL80211_RRF_PASSIVE_SCAN |
NL80211_RRF_NO_IBSS),
/* IEEE 802.11 channel 14 - Only JP enables
* this and for 802.11b only */
REG_RULE(2484-10, 2484+10, 20, 6, 20,
NL80211_RRF_PASSIVE_SCAN |
NL80211_RRF_NO_IBSS |
NL80211_RRF_NO_OFDM),
/* IEEE 802.11a, channel 36..48 */
REG_RULE(5180-10, 5240+10, 40, 6, 20,
NL80211_RRF_PASSIVE_SCAN |
NL80211_RRF_NO_IBSS),
/* NB: 5260 MHz - 5700 MHz requies DFS */
/* IEEE 802.11a, channel 149..165 */
REG_RULE(5745-10, 5825+10, 40, 6, 20,
NL80211_RRF_PASSIVE_SCAN |
NL80211_RRF_NO_IBSS),
}
};
static const struct ieee80211_regdomain *cfg80211_world_regdom =
&world_regdom;
#ifdef CONFIG_WIRELESS_OLD_REGULATORY
static char *ieee80211_regdom = "US";
module_param(ieee80211_regdom, charp, 0444);
MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain code");
/*
* We assume 40 MHz bandwidth for the old regulatory work.
* We make emphasis we are using the exact same frequencies
* as before
*/
static const struct ieee80211_regdomain us_regdom = {
.n_reg_rules = 6,
.alpha2 = "US",
.reg_rules = {
/* IEEE 802.11b/g, channels 1..11 */
REG_RULE(2412-10, 2462+10, 40, 6, 27, 0),
/* IEEE 802.11a, channel 36 */
REG_RULE(5180-10, 5180+10, 40, 6, 23, 0),
/* IEEE 802.11a, channel 40 */
REG_RULE(5200-10, 5200+10, 40, 6, 23, 0),
/* IEEE 802.11a, channel 44 */
REG_RULE(5220-10, 5220+10, 40, 6, 23, 0),
/* IEEE 802.11a, channels 48..64 */
REG_RULE(5240-10, 5320+10, 40, 6, 23, 0),
/* IEEE 802.11a, channels 149..165, outdoor */
REG_RULE(5745-10, 5825+10, 40, 6, 30, 0),
}
};
static const struct ieee80211_regdomain jp_regdom = {
.n_reg_rules = 3,
.alpha2 = "JP",
.reg_rules = {
/* IEEE 802.11b/g, channels 1..14 */
REG_RULE(2412-10, 2484+10, 40, 6, 20, 0),
/* IEEE 802.11a, channels 34..48 */
REG_RULE(5170-10, 5240+10, 40, 6, 20,
NL80211_RRF_PASSIVE_SCAN),
/* IEEE 802.11a, channels 52..64 */
REG_RULE(5260-10, 5320+10, 40, 6, 20,
NL80211_RRF_NO_IBSS |
NL80211_RRF_DFS),
}
};
static const struct ieee80211_regdomain eu_regdom = {
.n_reg_rules = 6,
/*
* This alpha2 is bogus, we leave it here just for stupid
* backward compatibility
*/
.alpha2 = "EU",
.reg_rules = {
/* IEEE 802.11b/g, channels 1..13 */
REG_RULE(2412-10, 2472+10, 40, 6, 20, 0),
/* IEEE 802.11a, channel 36 */
REG_RULE(5180-10, 5180+10, 40, 6, 23,
NL80211_RRF_PASSIVE_SCAN),
/* IEEE 802.11a, channel 40 */
REG_RULE(5200-10, 5200+10, 40, 6, 23,
NL80211_RRF_PASSIVE_SCAN),
/* IEEE 802.11a, channel 44 */
REG_RULE(5220-10, 5220+10, 40, 6, 23,
NL80211_RRF_PASSIVE_SCAN),
/* IEEE 802.11a, channels 48..64 */
REG_RULE(5240-10, 5320+10, 40, 6, 20,
NL80211_RRF_NO_IBSS |
NL80211_RRF_DFS),
/* IEEE 802.11a, channels 100..140 */
REG_RULE(5500-10, 5700+10, 40, 6, 30,
NL80211_RRF_NO_IBSS |
NL80211_RRF_DFS),
}
};
static const struct ieee80211_regdomain *static_regdom(char *alpha2)
{
if (alpha2[0] == 'U' && alpha2[1] == 'S')
return &us_regdom;
if (alpha2[0] == 'J' && alpha2[1] == 'P')
return &jp_regdom;
if (alpha2[0] == 'E' && alpha2[1] == 'U')
return &eu_regdom;
/* Default, as per the old rules */
return &us_regdom;
}
static bool is_old_static_regdom(const struct ieee80211_regdomain *rd)
{
if (rd == &us_regdom || rd == &jp_regdom || rd == &eu_regdom)
return true;
return false;
}
#else
static inline bool is_old_static_regdom(const struct ieee80211_regdomain *rd)
{
return false;
}
#endif
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;
if (is_old_static_regdom(cfg80211_regdomain))
cfg80211_regdomain = NULL;
kfree(cfg80211_regdomain);
kfree(cfg80211_world_regdom);
cfg80211_world_regdom = &world_regdom;
cfg80211_regdomain = NULL;
}
/*
* Dynamic world regulatory domain requested by the wireless
* core upon initialization
*/
static void update_world_regdomain(const struct ieee80211_regdomain *rd)
{
BUG_ON(!last_request);
reset_regdomains();
cfg80211_world_regdom = rd;
cfg80211_regdomain = rd;
}
bool is_world_regdom(const char *alpha2)
{
if (!alpha2)
return false;
if (alpha2[0] == '0' && alpha2[1] == '0')
return true;
return false;
}
static bool is_alpha2_set(const char *alpha2)
{
if (!alpha2)
return false;
if (alpha2[0] != 0 && alpha2[1] != 0)
return true;
return false;
}
static bool is_alpha_upper(char letter)
{
/* ASCII A - Z */
if (letter >= 65 && letter <= 90)
return true;
return false;
}
static bool is_unknown_alpha2(const char *alpha2)
{
if (!alpha2)
return false;
/*
* Special case where regulatory domain was built by driver
* but a specific alpha2 cannot be determined
*/
if (alpha2[0] == '9' && alpha2[1] == '9')
return true;
return false;
}
static bool is_intersected_alpha2(const char *alpha2)
{
if (!alpha2)
return false;
/*
* Special case where regulatory domain is the
* result of an intersection between two regulatory domain
* structures
*/
if (alpha2[0] == '9' && alpha2[1] == '8')
return true;
return false;
}
static bool is_an_alpha2(const char *alpha2)
{
if (!alpha2)
return false;
if (is_alpha_upper(alpha2[0]) && is_alpha_upper(alpha2[1]))
return true;
return false;
}
static bool alpha2_equal(const char *alpha2_x, const char *alpha2_y)
{
if (!alpha2_x || !alpha2_y)
return false;
if (alpha2_x[0] == alpha2_y[0] &&
alpha2_x[1] == alpha2_y[1])
return true;
return false;
}
static bool regdom_changes(const char *alpha2)
{
assert_cfg80211_lock();
if (!cfg80211_regdomain)
return true;
if (alpha2_equal(cfg80211_regdomain->alpha2, alpha2))
return false;
return true;
}
/**
* 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;
}
/*
* This lets us keep regulatory code which is updated on a regulatory
* basis in userspace.
*/
static int call_crda(const char *alpha2)
{
char country_env[9 + 2] = "COUNTRY=";
char *envp[] = {
country_env,
NULL
};
if (!is_world_regdom((char *) alpha2))
printk(KERN_INFO "cfg80211: Calling CRDA for country: %c%c\n",
alpha2[0], alpha2[1]);
else
printk(KERN_INFO "cfg80211: Calling CRDA to update world "
"regulatory domain\n");
country_env[8] = alpha2[0];
country_env[9] = alpha2[1];
return kobject_uevent_env(®_pdev->dev.kobj, KOBJ_CHANGE, envp);
}
/* Used by nl80211 before kmalloc'ing our regulatory domain */
bool reg_is_valid_request(const char *alpha2)
{
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;
}
/* Returns value in KHz */
static u32 freq_max_bandwidth(const struct ieee80211_freq_range *freq_range,
u32 freq)
{
unsigned int i;
for (i = 0; i < ARRAY_SIZE(supported_bandwidths); i++) {
u32 start_freq_khz = freq - supported_bandwidths[i]/2;
u32 end_freq_khz = freq + supported_bandwidths[i]/2;
if (start_freq_khz >= freq_range->start_freq_khz &&
end_freq_khz <= freq_range->end_freq_khz)
return supported_bandwidths[i];
}
return 0;
}
/**
* 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
}
/*
* Converts a country IE to a regulatory domain. A regulatory domain
* structure has a lot of information which the IE doesn't yet have,
* so for the other values we use upper max values as we will intersect
* with our userspace regulatory agent to get lower bounds.
*/
static struct ieee80211_regdomain *country_ie_2_rd(
u8 *country_ie,
u8 country_ie_len,
u32 *checksum)
{
struct ieee80211_regdomain *rd = NULL;
unsigned int i = 0;
char alpha2[2];
u32 flags = 0;
u32 num_rules = 0, size_of_regd = 0;
u8 *triplets_start = NULL;
u8 len_at_triplet = 0;
/* the last channel we have registered in a subband (triplet) */
int last_sub_max_channel = 0;
*checksum = 0xDEADBEEF;
/* Country IE requirements */
BUG_ON(country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN ||
country_ie_len & 0x01);
alpha2[0] = country_ie[0];
alpha2[1] = country_ie[1];
/*
* Third octet can be:
* 'I' - Indoor
* 'O' - Outdoor
*
* anything else we assume is no restrictions
*/
if (country_ie[2] == 'I')
flags = NL80211_RRF_NO_OUTDOOR;
else if (country_ie[2] == 'O')
flags = NL80211_RRF_NO_INDOOR;
country_ie += 3;
country_ie_len -= 3;
triplets_start = country_ie;
len_at_triplet = country_ie_len;
*checksum ^= ((flags ^ alpha2[0] ^ alpha2[1]) << 8);
/*
* We need to build a reg rule for each triplet, but first we must
* calculate the number of reg rules we will need. We will need one
* for each channel subband
*/
while (country_ie_len >= 3) {
int end_channel = 0;
struct ieee80211_country_ie_triplet *triplet =
(struct ieee80211_country_ie_triplet *) country_ie;
int cur_sub_max_channel = 0, cur_channel = 0;
if (triplet->ext.reg_extension_id >=
IEEE80211_COUNTRY_EXTENSION_ID) {
country_ie += 3;
country_ie_len -= 3;
continue;
}
/* 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));
cur_channel = triplet->chans.first_channel;
cur_sub_max_channel = end_channel;
/* Basic sanity check */
if (cur_sub_max_channel < cur_channel)
return NULL;
/*
* Do not allow overlapping channels. Also channels
* passed in each subband must be monotonically
* increasing
*/
if (last_sub_max_channel) {
if (cur_channel <= last_sub_max_channel)
return NULL;
if (cur_sub_max_channel <= last_sub_max_channel)
return NULL;
}
/*
* When dot11RegulatoryClassesRequired is supported
* we can throw ext triplets as part of this soup,
* for now we don't care when those change as we
* don't support them
*/
*checksum ^= ((cur_channel ^ cur_sub_max_channel) << 8) |
((cur_sub_max_channel ^ cur_sub_max_channel) << 16) |
((triplet->chans.max_power ^ cur_sub_max_channel) << 24);
last_sub_max_channel = cur_sub_max_channel;
country_ie += 3;
country_ie_len -= 3;
num_rules++;
/*
* Note: this is not a IEEE requirement but
* simply a memory requirement
*/
if (num_rules > NL80211_MAX_SUPP_REG_RULES)
return NULL;
}
country_ie = triplets_start;
country_ie_len = len_at_triplet;
size_of_regd = sizeof(struct ieee80211_regdomain) +
(num_rules * sizeof(struct ieee80211_reg_rule));
rd = kzalloc(size_of_regd, GFP_KERNEL);
if (!rd)
return NULL;
rd->n_reg_rules = num_rules;
rd->alpha2[0] = alpha2[0];
rd->alpha2[1] = alpha2[1];
/* This time around we fill in the rd */
while (country_ie_len >= 3) {
int end_channel = 0;
struct ieee80211_country_ie_triplet *triplet =
(struct ieee80211_country_ie_triplet *) country_ie;
struct ieee80211_reg_rule *reg_rule = NULL;
struct ieee80211_freq_range *freq_range = NULL;
struct ieee80211_power_rule *power_rule = NULL;
/*
* Must parse if dot11RegulatoryClassesRequired is true,
* we don't support this yet
*/
if (triplet->ext.reg_extension_id >=
IEEE80211_COUNTRY_EXTENSION_ID) {
country_ie += 3;
country_ie_len -= 3;
continue;
}
reg_rule = &rd->reg_rules[i];
freq_range = ®_rule->freq_range;
power_rule = ®_rule->power_rule;
reg_rule->flags = flags;
/* 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));
/*
* The +10 is since the regulatory domain expects
* the actual band edge, not the center of freq for
* its start and end freqs, assuming 20 MHz bandwidth on
* the channels passed
*/
freq_range->start_freq_khz =
MHZ_TO_KHZ(ieee80211_channel_to_frequency(
triplet->chans.first_channel) - 10);
freq_range->end_freq_khz =
MHZ_TO_KHZ(ieee80211_channel_to_frequency(
end_channel) + 10);
/*
* These are large arbitrary values we use to intersect later.
* Increment this if we ever support >= 40 MHz channels
* in IEEE 802.11
*/
freq_range->max_bandwidth_khz = MHZ_TO_KHZ(40);
power_rule->max_antenna_gain = DBI_TO_MBI(100);
power_rule->max_eirp = DBM_TO_MBM(100);
country_ie += 3;
country_ie_len -= 3;
i++;
BUG_ON(i > NL80211_MAX_SUPP_REG_RULES);
}
return rd;
}
/*
* Helper for regdom_intersect(), this does the real
* mathematical intersection fun
*/
static int reg_rules_intersect(
const struct ieee80211_reg_rule *rule1,
const struct ieee80211_reg_rule *rule2,
struct ieee80211_reg_rule *intersected_rule)
{
const struct ieee80211_freq_range *freq_range1, *freq_range2;
struct ieee80211_freq_range *freq_range;
const struct ieee80211_power_rule *power_rule1, *power_rule2;
struct ieee80211_power_rule *power_rule;
u32 freq_diff;
freq_range1 = &rule1->freq_range;
freq_range2 = &rule2->freq_range;
freq_range = &intersected_rule->freq_range;
power_rule1 = &rule1->power_rule;
power_rule2 = &rule2->power_rule;
power_rule = &intersected_rule->power_rule;
freq_range->start_freq_khz = max(freq_range1->start_freq_khz,
freq_range2->start_freq_khz);
freq_range->end_freq_khz = min(freq_range1->end_freq_khz,
freq_range2->end_freq_khz);
freq_range->max_bandwidth_khz = min(freq_range1->max_bandwidth_khz,
freq_range2->max_bandwidth_khz);
freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
if (freq_range->max_bandwidth_khz > freq_diff)
freq_range->max_bandwidth_khz = freq_diff;
power_rule->max_eirp = min(power_rule1->max_eirp,
power_rule2->max_eirp);
power_rule->max_antenna_gain = min(power_rule1->max_antenna_gain,
power_rule2->max_antenna_gain);
intersected_rule->flags = (rule1->flags | rule2->flags);
if (!is_valid_reg_rule(intersected_rule))
return -EINVAL;
return 0;
}
/**
* regdom_intersect - do the intersection between two regulatory domains
* @rd1: first regulatory domain
* @rd2: second regulatory domain
*
* Use this function to get the intersection between two regulatory domains.
* Once completed we will mark the alpha2 for the rd as intersected, "98",
* as no one single alpha2 can represent this regulatory domain.
*
* Returns a pointer to the regulatory domain structure which will hold the
* resulting intersection of rules between rd1 and rd2. We will
* kzalloc() this structure for you.
*/
static struct ieee80211_regdomain *regdom_intersect(
const struct ieee80211_regdomain *rd1,
const struct ieee80211_regdomain *rd2)
{
int r, size_of_regd;
unsigned int x, y;
unsigned int num_rules = 0, rule_idx = 0;
const struct ieee80211_reg_rule *rule1, *rule2;
struct ieee80211_reg_rule *intersected_rule;
struct ieee80211_regdomain *rd;
/* This is just a dummy holder to help us count */
struct ieee80211_reg_rule irule;
/* Uses the stack temporarily for counter arithmetic */
intersected_rule = &irule;
memset(intersected_rule, 0, sizeof(struct ieee80211_reg_rule));
if (!rd1 || !rd2)
return NULL;
/*
* First we get a count of the rules we'll need, then we actually
* build them. This is to so we can malloc() and free() a
* regdomain once. The reason we use reg_rules_intersect() here
* is it will return -EINVAL if the rule computed makes no sense.
* All rules that do check out OK are valid.
*/
for (x = 0; x < rd1->n_reg_rules; x++) {
rule1 = &rd1->reg_rules[x];
for (y = 0; y < rd2->n_reg_rules; y++) {
rule2 = &rd2->reg_rules[y];
if (!reg_rules_intersect(rule1, rule2,
intersected_rule))
num_rules++;
memset(intersected_rule, 0,
sizeof(struct ieee80211_reg_rule));
}
}
if (!num_rules)
return NULL;
size_of_regd = sizeof(struct ieee80211_regdomain) +
((num_rules + 1) * sizeof(struct ieee80211_reg_rule));
rd = kzalloc(size_of_regd, GFP_KERNEL);
if (!rd)
return NULL;
for (x = 0; x < rd1->n_reg_rules; x++) {
rule1 = &rd1->reg_rules[x];
for (y = 0; y < rd2->n_reg_rules; y++) {
rule2 = &rd2->reg_rules[y];
/*
* This time around instead of using the stack lets
* write to the target rule directly saving ourselves
* a memcpy()
*/
intersected_rule = &rd->reg_rules[rule_idx];
r = reg_rules_intersect(rule1, rule2,
intersected_rule);
/*
* No need to memset here the intersected rule here as
* we're not using the stack anymore
*/
if (r)
continue;
rule_idx++;
}
}
if (rule_idx != num_rules) {
kfree(rd);
return NULL;
}
rd->n_reg_rules = num_rules;
rd->alpha2[0] = '9';
rd->alpha2[1] = '8';
return rd;
}
/*
* XXX: add support for the rest of enum nl80211_reg_rule_flags, we may
* want to just have the channel structure use these
*/
static u32 map_regdom_flags(u32 rd_flags)
{
u32 channel_flags = 0;
if (rd_flags & NL80211_RRF_PASSIVE_SCAN)
channel_flags |= IEEE80211_CHAN_PASSIVE_SCAN;
if (rd_flags & NL80211_RRF_NO_IBSS)
channel_flags |= IEEE80211_CHAN_NO_IBSS;
if (rd_flags & NL80211_RRF_DFS)
channel_flags |= IEEE80211_CHAN_RADAR;
return channel_flags;
}
static int freq_reg_info_regd(struct wiphy *wiphy,
u32 center_freq,
u32 *bandwidth,
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;
u32 max_bandwidth = 0;
regd = custom_regd ? custom_regd : cfg80211_regdomain;
/*
* Follow the driver's regulatory domain, if present, unless a country
* IE has been processed or a user wants to help complaince further
*/
if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
last_request->initiator != NL80211_REGDOM_SET_BY_USER &&
wiphy->regd)
regd = wiphy->regd;
if (!regd)
return -EINVAL;
for (i = 0; i < regd->n_reg_rules; i++) {
const struct ieee80211_reg_rule *rr;
const struct ieee80211_freq_range *fr = NULL;
const struct ieee80211_power_rule *pr = NULL;
rr = ®d->reg_rules[i];
fr = &rr->freq_range;
pr = &rr->power_rule;
/*
* We only need to know if one frequency rule was
* was in center_freq's band, that's enough, so lets
* not overwrite it once found
*/
if (!band_rule_found)
band_rule_found = freq_in_rule_band(fr, center_freq);
max_bandwidth = freq_max_bandwidth(fr, center_freq);
if (max_bandwidth && *bandwidth <= max_bandwidth) {
*reg_rule = rr;
*bandwidth = max_bandwidth;
break;
}
}
if (!band_rule_found)
return -ERANGE;
return !max_bandwidth;
}
EXPORT_SYMBOL(freq_reg_info);
int freq_reg_info(struct wiphy *wiphy, u32 center_freq, u32 *bandwidth,
const struct ieee80211_reg_rule **reg_rule)
{
return freq_reg_info_regd(wiphy, center_freq,
bandwidth, reg_rule, NULL);
}
static void handle_channel(struct wiphy *wiphy, enum ieee80211_band band,
unsigned int chan_idx)
{
int r;
u32 flags;
u32 max_bandwidth = 0;
const struct ieee80211_reg_rule *reg_rule = NULL;
const struct ieee80211_power_rule *power_rule = 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),
&max_bandwidth, ®_rule);
if (r) {
/*
* This means no regulatory rule was found in the country IE
* with a frequency range on the center_freq's band, since
* IEEE-802.11 allows for a country IE to have a subset of the
* regulatory information provided in a country we ignore
* disabling the channel unless at least one reg rule was
* found on the center_freq's band. For details see this
* clarification:
*
* http://tinyurl.com/11d-clarification
*/
if (r == -ERANGE &&
last_request->initiator ==
NL80211_REGDOM_SET_BY_COUNTRY_IE) {
#ifdef CONFIG_CFG80211_REG_DEBUG
printk(KERN_DEBUG "cfg80211: Leaving channel %d MHz "
"intact on %s - no rule found in band on "
"Country IE\n",
chan->center_freq, wiphy_name(wiphy));
#endif
} else {
/*
* In this case we know the country IE has at least one reg rule
* for the band so we respect its band definitions
*/
#ifdef CONFIG_CFG80211_REG_DEBUG
if (last_request->initiator ==
NL80211_REGDOM_SET_BY_COUNTRY_IE)
printk(KERN_DEBUG "cfg80211: Disabling "
"channel %d MHz on %s due to "
"Country IE\n",
chan->center_freq, wiphy_name(wiphy));
#endif
flags |= IEEE80211_CHAN_DISABLED;
chan->flags = flags;
}
return;
}
power_rule = ®_rule->power_rule;
if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
request_wiphy && request_wiphy == wiphy &&
request_wiphy->strict_regulatory) {
/*
* This gaurantees the driver's requested regulatory domain
* will always be used as a base for further regulatory
* settings
*/
chan->flags = chan->orig_flags =
map_regdom_flags(reg_rule->flags);
chan->max_antenna_gain = chan->orig_mag =
(int) MBI_TO_DBI(power_rule->max_antenna_gain);
chan->max_bandwidth = KHZ_TO_MHZ(max_bandwidth);
chan->max_power = chan->orig_mpwr =
(int) MBM_TO_DBM(power_rule->max_eirp);
return;
}
chan->flags = flags | map_regdom_flags(reg_rule->flags);
chan->max_antenna_gain = min(chan->orig_mag,
(int) MBI_TO_DBI(power_rule->max_antenna_gain));
chan->max_bandwidth = KHZ_TO_MHZ(max_bandwidth);
if (chan->orig_mpwr)
chan->max_power = min(chan->orig_mpwr,
(int) MBM_TO_DBM(power_rule->max_eirp));