linux/net/wireless/reg.c
Luis R. Rodriguez 371842448c cfg80211: fix regression on beacon world roaming feature
A regression was added through patch a4ed90d6:

"cfg80211: respect API on orig_flags on channel for beacon hint"

We did indeed respect _orig flags but the intention was not clearly
stated in the commit log. This patch fixes firmware issues picked
up by iwlwifi when we lift passive scan of beaconing restrictions
on channels its EEPROM has been configured to always enable.

By doing so though we also disallowed beacon hints on devices
registering their wiphy with custom world regulatory domains
enabled, this happens to be currently ath5k, ath9k and ar9170.
The passive scan and beacon restrictions on those devices would
never be lifted even if we did find a beacon and the hardware did
support such enhancements when world roaming.

Since Johannes indicates iwlwifi firmware cannot be changed to
allow beacon hinting we set up a flag now to specifically allow
drivers to disable beacon hints for devices which cannot use them.

We enable the flag on iwlwifi to disable beacon hints and by default
enable it for all other drivers. It should be noted beacon hints lift
passive scan flags and beacon restrictions when we receive a beacon from
an AP on any 5 GHz non-DFS channels, and channels 12-14 on the 2.4 GHz
band. We don't bother with channels 1-11 as those channels are allowed
world wide.

This should fix world roaming for ath5k, ath9k and ar9170, thereby
improving scan time when we receive the first beacon from any AP,
and also enabling beaconing operation (AP/IBSS/Mesh) on cards which
would otherwise not be allowed to do so. Drivers not using custom
regulatory stuff (wiphy_apply_custom_regulatory()) were not affected
by this as the orig_flags for the channels would have been cleared
upon wiphy registration.

I tested this with a world roaming ath5k card.

Cc: Jouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-08-03 16:31:21 -04:00

2376 lines
62 KiB
C

/*
* Copyright 2002-2005, Instant802 Networks, Inc.
* Copyright 2005-2006, Devicescape Software, Inc.
* Copyright 2007 Johannes Berg <johannes@sipsolutions.net>
* Copyright 2008 Luis R. Rodriguez <lrodriguz@atheros.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
/**
* DOC: Wireless regulatory infrastructure
*
* The usual implementation is for a driver to read a device EEPROM to
* determine which regulatory domain it should be operating under, then
* looking up the allowable channels in a driver-local table and finally
* registering those channels in the wiphy structure.
*
* Another set of compliance enforcement is for drivers to use their
* own compliance limits which can be stored on the EEPROM. The host
* driver or firmware may ensure these are used.
*
* In addition to all this we provide an extra layer of regulatory
* conformance. For drivers which do not have any regulatory
* information CRDA provides the complete regulatory solution.
* For others it provides a community effort on further restrictions
* to enhance compliance.
*
* Note: When number of rules --> infinity we will not be able to
* index on alpha2 any more, instead we'll probably have to
* rely on some SHA1 checksum of the regdomain for example.
*
*/
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/random.h>
#include <linux/nl80211.h>
#include <linux/platform_device.h>
#include <net/cfg80211.h>
#include "core.h"
#include "reg.h"
#include "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;
/*
* 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";
#else
static char *ieee80211_regdom = "00";
#endif
module_param(ieee80211_regdom, charp, 0444);
MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain code");
#ifdef CONFIG_WIRELESS_OLD_REGULATORY
/*
* 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(&reg_pdev->dev.kobj, KOBJ_CHANGE, envp);
}
/* Used by nl80211 before kmalloc'ing our regulatory domain */
bool reg_is_valid_request(const char *alpha2)
{
assert_cfg80211_lock();
if (!last_request)
return false;
return alpha2_equal(last_request->alpha2, alpha2);
}
/* Sanity check on a regulatory rule */
static bool is_valid_reg_rule(const struct ieee80211_reg_rule *rule)
{
const struct ieee80211_freq_range *freq_range = &rule->freq_range;
u32 freq_diff;
if (freq_range->start_freq_khz <= 0 || freq_range->end_freq_khz <= 0)
return false;
if (freq_range->start_freq_khz > freq_range->end_freq_khz)
return false;
freq_diff = freq_range->end_freq_khz - freq_range->start_freq_khz;
if (freq_range->end_freq_khz <= freq_range->start_freq_khz ||
freq_range->max_bandwidth_khz > freq_diff)
return false;
return true;
}
static bool is_valid_rd(const struct ieee80211_regdomain *rd)
{
const struct ieee80211_reg_rule *reg_rule = NULL;
unsigned int i;
if (!rd->n_reg_rules)
return false;
if (WARN_ON(rd->n_reg_rules > NL80211_MAX_SUPP_REG_RULES))
return false;
for (i = 0; i < rd->n_reg_rules; i++) {
reg_rule = &rd->reg_rules[i];
if (!is_valid_reg_rule(reg_rule))
return false;
}
return true;
}
static bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_range,
u32 center_freq_khz,
u32 bw_khz)
{
u32 start_freq_khz, end_freq_khz;
start_freq_khz = center_freq_khz - (bw_khz/2);
end_freq_khz = center_freq_khz + (bw_khz/2);
if (start_freq_khz >= freq_range->start_freq_khz &&
end_freq_khz <= freq_range->end_freq_khz)
return true;
return false;
}
/**
* freq_in_rule_band - tells us if a frequency is in a frequency band
* @freq_range: frequency rule we want to query
* @freq_khz: frequency we are inquiring about
*
* This lets us know if a specific frequency rule is or is not relevant to
* a specific frequency's band. Bands are device specific and artificial
* definitions (the "2.4 GHz band" and the "5 GHz band"), however it is
* safe for now to assume that a frequency rule should not be part of a
* frequency's band if the start freq or end freq are off by more than 2 GHz.
* This resolution can be lowered and should be considered as we add
* regulatory rule support for other "bands".
**/
static bool freq_in_rule_band(const struct ieee80211_freq_range *freq_range,
u32 freq_khz)
{
#define ONE_GHZ_IN_KHZ 1000000
if (abs(freq_khz - freq_range->start_freq_khz) <= (2 * ONE_GHZ_IN_KHZ))
return true;
if (abs(freq_khz - freq_range->end_freq_khz) <= (2 * ONE_GHZ_IN_KHZ))
return true;
return false;
#undef ONE_GHZ_IN_KHZ
}
/*
* 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 = &reg_rule->freq_range;
power_rule = &reg_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 desired_bw_khz,
const struct ieee80211_reg_rule **reg_rule,
const struct ieee80211_regdomain *custom_regd)
{
int i;
bool band_rule_found = false;
const struct ieee80211_regdomain *regd;
bool bw_fits = false;
if (!desired_bw_khz)
desired_bw_khz = MHZ_TO_KHZ(20);
regd = custom_regd ? custom_regd : cfg80211_regdomain;
/*
* Follow the driver's regulatory domain, if present, unless a country
* IE has been processed or a user wants to help complaince further
*/
if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE &&
last_request->initiator != NL80211_REGDOM_SET_BY_USER &&
wiphy->regd)
regd = wiphy->regd;
if (!regd)
return -EINVAL;
for (i = 0; i < regd->n_reg_rules; i++) {
const struct ieee80211_reg_rule *rr;
const struct ieee80211_freq_range *fr = NULL;
const struct ieee80211_power_rule *pr = NULL;
rr = &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;
}
EXPORT_SYMBOL(freq_reg_info);
int freq_reg_info(struct wiphy *wiphy,
u32 center_freq,
u32 desired_bw_khz,
const struct ieee80211_reg_rule **reg_rule)
{
assert_cfg80211_lock();
return freq_reg_info_regd(wiphy,
center_freq,
desired_bw_khz,
reg_rule,
NULL);
}
/*
* Note that right now we assume the desired channel bandwidth
* is always 20 MHz for each individual channel (HT40 uses 20 MHz
* per channel, the primary and the extension channel). To support
* smaller custom bandwidths such as 5 MHz or 10 MHz we'll need a
* new ieee80211_channel.target_bw and re run the regulatory check
* on the wiphy with the target_bw specified. Then we can simply use
* that below for the desired_bw_khz below.
*/
static void handle_channel(struct wiphy *wiphy, enum ieee80211_band band,
unsigned int chan_idx)
{
int r;
u32 flags, bw_flags = 0;
u32 desired_bw_khz = MHZ_TO_KHZ(20);
const struct ieee80211_reg_rule *reg_rule = NULL;
const struct ieee80211_power_rule *power_rule = NULL;
const struct ieee80211_freq_range *freq_range = NULL;
struct ieee80211_supported_band *sband;
struct ieee80211_channel *chan;
struct wiphy *request_wiphy = NULL;
assert_cfg80211_lock();
request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
sband = wiphy->bands[band];
BUG_ON(chan_idx >= sband->n_channels);
chan = &sband->channels[chan_idx];
flags = chan->orig_flags;
r = freq_reg_info(wiphy,
MHZ_TO_KHZ(chan->center_freq),
desired_bw_khz,
&reg_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 = &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->strict_regulatory) {
/*
* This gaurantees the driver's requested regulatory domain
* will always be used as a base for further regulatory
* settings
*/
chan->flags = chan->orig_flags =
map_regdom_flags(reg_rule->flags) | bw_flags;
chan->max_antenna_gain = chan->orig_mag =
(int) MBI_TO_DBI(power_rule->max_antenna_gain);
chan->max_bandwidth = KHZ_TO_MHZ(desired_bw_khz);
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));
chan->max_bandwidth = KHZ_TO_MHZ(desired_bw_khz);
if (chan->orig_mpwr)
chan->max_power = min(chan->orig_mpwr,
(int) MBM_TO_DBM(power_rule->max_eirp));
else
chan->max_power = (int) MBM_TO_DBM(power_rule->max_eirp);
}
static void handle_band(struct wiphy *wiphy, enum ieee80211_band band)
{
unsigned int i;
struct ieee80211_supported_band *sband;
BUG_ON(!wiphy->bands[band]);
sband = wiphy->bands[band];
for (i = 0; i < sband->n_channels; i++)
handle_channel(wiphy, band, i);
}
static bool ignore_reg_update(struct wiphy *wiphy,
enum nl80211_reg_initiator initiator)
{
if (!last_request)
return true;
if (initiator == NL80211_REGDOM_SET_BY_CORE &&
wiphy->custom_regulatory)
return true;
/*
* wiphy->regd will be set once the device has its own
* desired regulatory domain set
*/
if (wiphy->strict_regulatory && !wiphy->regd &&
!is_world_regdom(last_request->alpha2))
return true;
return false;
}
static void update_all_wiphy_regulatory(enum nl80211_reg_initiator initiator)
{
struct cfg80211_registered_device *drv;
list_for_each_entry(drv, &cfg80211_drv_list, list)
wiphy_update_regulatory(&drv->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->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->custom_regulatory)
return true;
return false;
}
/* Reap the advantages of previously found beacons */
static void reg_process_beacons(struct wiphy *wiphy)
{
/*
* Means we are just firing up cfg80211, so no beacons would
* have been processed yet.
*/
if (!last_request)
return;
if (!reg_is_world_roaming(wiphy))
return;
wiphy_update_beacon_reg(wiphy);
}
static bool is_ht40_not_allowed(struct ieee80211_channel *chan)
{
if (!chan)
return true;
if (chan->flags & IEEE80211_CHAN_DISABLED)
return true;
/* This would happen when regulatory rules disallow HT40 completely */
if (IEEE80211_CHAN_NO_HT40 == (chan->flags & (IEEE80211_CHAN_NO_HT40)))
return true;
return false;
}
static void reg_process_ht_flags_channel(struct wiphy *wiphy,
enum ieee80211_band band,
unsigned int chan_idx)
{
struct ieee80211_supported_band *sband;
struct ieee80211_channel *channel;
struct ieee80211_channel *channel_before = NULL, *channel_after = NULL;
unsigned int i;
assert_cfg80211_lock();
sband = wiphy->bands[band];
BUG_ON(chan_idx >= sband->n_channels);
channel = &sband->channels[chan_idx];
if (is_ht40_not_allowed(channel)) {
channel->flags |= IEEE80211_CHAN_NO_HT40;
return;
}
/*
* We need to ensure the extension channels exist to
* be able to use HT40- or HT40+, this finds them (or not)
*/
for (i = 0; i < sband->n_channels; i++) {
struct ieee80211_channel *c = &sband->channels[i];
if (c->center_freq == (channel->center_freq - 20))
channel_before = c;
if (c->center_freq == (channel->center_freq + 20))
channel_after = c;
}
/*
* Please note that this assumes target bandwidth is 20 MHz,
* if that ever changes we also need to change the below logic
* to include that as well.
*/
if (is_ht40_not_allowed(channel_before))
channel->flags |= IEEE80211_CHAN_NO_HT40MINUS;
else
channel->flags &= ~IEEE80211_CHAN_NO_HT40MINUS;
if (is_ht40_not_allowed(channel_after))
channel->flags |= IEEE80211_CHAN_NO_HT40PLUS;
else
channel->flags &= ~IEEE80211_CHAN_NO_HT40PLUS;
}
static void reg_process_ht_flags_band(struct wiphy *wiphy,
enum ieee80211_band band)
{
unsigned int i;
struct ieee80211_supported_band *sband;
BUG_ON(!wiphy->bands[band]);
sband = wiphy->bands[band];
for (i = 0; i < sband->n_channels; i++)
reg_process_ht_flags_channel(wiphy, band, i);
}
static void reg_process_ht_flags(struct wiphy *wiphy)
{
enum ieee80211_band band;
if (!wiphy)
return;
for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
if (wiphy->bands[band])
reg_process_ht_flags_band(wiphy, band);
}
}
void wiphy_update_regulatory(struct wiphy *wiphy,
enum nl80211_reg_initiator initiator)
{
enum ieee80211_band band;
if (ignore_reg_update(wiphy, initiator))
goto out;
for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
if (wiphy->bands[band])
handle_band(wiphy, band);
}
out:
reg_process_beacons(wiphy);
reg_process_ht_flags(wiphy);
if (wiphy->reg_notifier)
wiphy->reg_notifier(wiphy, last_request);
}
static void handle_channel_custom(struct wiphy *wiphy,
enum ieee80211_band band,
unsigned int chan_idx,
const struct ieee80211_regdomain *regd)
{
int r;
u32 desired_bw_khz = MHZ_TO_KHZ(20);
u32 bw_flags = 0;
const struct ieee80211_reg_rule *reg_rule = NULL;
const struct ieee80211_power_rule *power_rule = NULL;
const struct ieee80211_freq_range *freq_range = NULL;
struct ieee80211_supported_band *sband;
struct ieee80211_channel *chan;
assert_cfg80211_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) {
chan->flags = IEEE80211_CHAN_DISABLED;
return;
}
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_bandwidth = KHZ_TO_MHZ(desired_bw_khz);
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(&cfg80211_mutex);
for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
if (!wiphy->bands[band])
continue;
handle_band_custom(wiphy, band, regd);
bands_set++;
}
mutex_unlock(&cfg80211_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);
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;
}
/*
* 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 -EINVAL;
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
* different Country IE alpha2s. We could
* intersect them, but that seems unlikely
* to be correct. Reject second one for now.
*/
if (regdom_changes(pending_request->alpha2))
return -EOPNOTSUPP;
return -EALREADY;
}
/*
* Two consecutive Country IE hints on the same wiphy.
* This should be picked up early by the driver/stack
*/
if (WARN_ON(regdom_changes(pending_request->alpha2)))
return 0;
return -EALREADY;
}
return REG_INTERSECT;
case NL80211_REGDOM_SET_BY_DRIVER:
if (last_request->initiator == NL80211_REGDOM_SET_BY_CORE) {
if (is_old_static_regdom(cfg80211_regdomain))
return 0;
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 (!is_old_static_regdom(cfg80211_regdomain) &&
!regdom_changes(pending_request->alpha2))
return -EALREADY;
return 0;
}
return -EINVAL;
}
/**
* __regulatory_hint - hint to the wireless core a regulatory domain
* @wiphy: if the hint comes from country information from an AP, this
* is required to be set to the wiphy that received the information
* @pending_request: the regulatory request currently being processed
*
* The Wireless subsystem can use this function to hint to the wireless core
* what it believes should be the current regulatory domain.
*
* Returns zero if all went fine, %-EALREADY if a regulatory domain had
* already been set or other standard error codes.
*
* Caller must hold &cfg80211_mutex
*/
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;
/* When r == REG_INTERSECT we do need to call CRDA */
if (r < 0) {
/*
* Since CRDA will not be called in this case as we already
* have applied the requested regulatory domain before we just
* inform userspace we have processed the request
*/
if (r == -EALREADY)
nl80211_send_reg_change_event(last_request);
return r;
}
return call_crda(last_request->alpha2);
}
/* This processes *all* regulatory hints */
static void reg_process_hint(struct regulatory_request *reg_request)
{
int r = 0;
struct wiphy *wiphy = NULL;
BUG_ON(!reg_request->alpha2);
mutex_lock(&cfg80211_mutex);
if (wiphy_idx_valid(reg_request->wiphy_idx))
wiphy = wiphy_idx_to_wiphy(reg_request->wiphy_idx);
if (reg_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
!wiphy) {
kfree(reg_request);
goto out;
}
r = __regulatory_hint(wiphy, reg_request);
/* This is required so that the orig_* parameters are saved */
if (r == -EALREADY && wiphy && wiphy->strict_regulatory)
wiphy_update_regulatory(wiphy, reg_request->initiator);
out:
mutex_unlock(&cfg80211_mutex);
}
/* Processes regulatory hints, this is all the NL80211_REGDOM_SET_BY_* */
static void reg_process_pending_hints(void)
{
struct regulatory_request *reg_request;
spin_lock(&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);
spin_unlock(&reg_requests_lock);
reg_process_hint(reg_request);
spin_lock(&reg_requests_lock);
}
spin_unlock(&reg_requests_lock);
}
/* Processes beacon hints -- this has nothing to do with country IEs */
static void reg_process_pending_beacon_hints(void)
{
struct cfg80211_registered_device *drv;
struct reg_beacon *pending_beacon, *tmp;
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(drv, &cfg80211_drv_list, list)
wiphy_update_new_beacon(&drv->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 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() */
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];
request->initiator = NL80211_REGDOM_SET_BY_CORE;
queue_regulatory_request(request);
/*
* This ensures last_request is populated once modules
* come swinging in and calling regulatory hints and
* wiphy_apply_custom_regulatory().
*/
flush_scheduled_work();
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);
static bool reg_same_country_ie_hint(struct wiphy *wiphy,
u32 country_ie_checksum)
{
struct wiphy *request_wiphy;
assert_cfg80211_lock();
if (unlikely(last_request->initiator !=
NL80211_REGDOM_SET_BY_COUNTRY_IE))
return false;
request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
if (!request_wiphy)
return false;
if (likely(request_wiphy != wiphy))
return !country_ie_integrity_changes(country_ie_checksum);
/*
* We should not have let these through at this point, they
* should have been picked up earlier by the first alpha2 check
* on the device
*/
if (WARN_ON(!country_ie_integrity_changes(country_ie_checksum)))
return true;
return false;
}
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;
struct regulatory_request *request;
mutex_lock(&cfg80211_mutex);
if (unlikely(!last_request)) {
mutex_unlock(&cfg80211_mutex);
return;
}
/* IE len must be evenly divisible by 2 */
if (country_ie_len & 0x01)
goto out;
if (country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN)
goto out;
/*
* Pending country IE processing, this can happen after we
* call CRDA and wait for a response if a beacon was received before
* we were able to process the last regulatory_hint_11d() call
*/
if (country_ie_regdomain)
goto out;
alpha2[0] = country_ie[0];
alpha2[1] = country_ie[1];
if (country_ie[2] == 'I')
env = ENVIRON_INDOOR;
else if (country_ie[2] == 'O')
env = ENVIRON_OUTDOOR;
/*
* We will run this for *every* beacon processed for the BSSID, so
* we optimize an early check to exit out early if we don't have to
* do anything
*/
if (likely(last_request->initiator ==
NL80211_REGDOM_SET_BY_COUNTRY_IE &&
wiphy_idx_valid(last_request->wiphy_idx))) {
struct cfg80211_registered_device *drv_last_ie;
drv_last_ie =
cfg80211_drv_by_wiphy_idx(last_request->wiphy_idx);
/*
* Lets keep this simple -- we trust the first AP
* after we intersect with CRDA
*/
if (likely(&drv_last_ie->wiphy == wiphy)) {
/*
* Ignore IEs coming in on this wiphy with
* the same alpha2 and environment cap
*/
if (likely(alpha2_equal(drv_last_ie->country_ie_alpha2,
alpha2) &&
env == drv_last_ie->env)) {
goto out;
}
/*
* the wiphy moved on to another BSSID or the AP
* was reconfigured. XXX: We need to deal with the
* case where the user suspends and goes to goes
* to another country, and then gets IEs from an
* AP with different settings
*/
goto out;
} else {
/*
* Ignore IEs coming in on two separate wiphys with
* the same alpha2 and environment cap
*/
if (likely(alpha2_equal(drv_last_ie->country_ie_alpha2,
alpha2) &&
env == drv_last_ie->env)) {
goto out;
}
/* We could potentially intersect though */
goto out;
}
}
rd = country_ie_2_rd(country_ie, country_ie_len, &checksum);
if (!rd)
goto out;
/*
* This will not happen right now but we leave it here for the
* the future when we want to add suspend/resume support and having
* the user move to another country after doing so, or having the user
* move to another AP. Right now we just trust the first AP.
*
* If we hit this before we add this support we want to be informed of
* it as it would indicate a mistake in the current design
*/
if (WARN_ON(reg_same_country_ie_hint(wiphy, checksum)))
goto free_rd_out;
request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);
if (!request)
goto free_rd_out;
/*
* We keep this around for when CRDA comes back with a response so
* we can intersect with that
*/
country_ie_regdomain = rd;
request->wiphy_idx = get_wiphy_idx(wiphy);
request->alpha2[0] = rd->alpha2[0];
request->alpha2[1] = rd->alpha2[1];
request->initiator = NL80211_REGDOM_SET_BY_COUNTRY_IE;
request->country_ie_checksum = checksum;
request->country_ie_env = env;
mutex_unlock(&cfg80211_mutex);
queue_regulatory_request(request);
return;
free_rd_out:
kfree(rd);
out:
mutex_unlock(&cfg80211_mutex);
}
EXPORT_SYMBOL(regulatory_hint_11d);
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;
#ifdef CONFIG_CFG80211_REG_DEBUG
printk(KERN_DEBUG "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));
#endif
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;
printk(KERN_INFO "\t(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)
printk(KERN_INFO "\t(%d KHz - %d KHz @ %d KHz), "
"(%d mBi, %d mBm)\n",
freq_range->start_freq_khz,
freq_range->end_freq_khz,
freq_range->max_bandwidth_khz,
power_rule->max_antenna_gain,
power_rule->max_eirp);
else
printk(KERN_INFO "\t(%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 *drv;
drv = cfg80211_drv_by_wiphy_idx(
last_request->wiphy_idx);
if (drv) {
printk(KERN_INFO "cfg80211: Current regulatory "
"domain updated by AP to: %c%c\n",
drv->country_ie_alpha2[0],
drv->country_ie_alpha2[1]);
} else
printk(KERN_INFO "cfg80211: Current regulatory "
"domain intersected: \n");
} else
printk(KERN_INFO "cfg80211: Current regulatory "
"domain intersected: \n");
} else if (is_world_regdom(rd->alpha2))
printk(KERN_INFO "cfg80211: World regulatory "
"domain updated:\n");
else {
if (is_unknown_alpha2(rd->alpha2))
printk(KERN_INFO "cfg80211: Regulatory domain "
"changed to driver built-in settings "
"(unknown country)\n");
else
printk(KERN_INFO "cfg80211: Regulatory domain "
"changed to country: %c%c\n",
rd->alpha2[0], rd->alpha2[1]);
}
print_rd_rules(rd);
}
static void print_regdomain_info(const struct ieee80211_regdomain *rd)
{
printk(KERN_INFO "cfg80211: Regulatory domain: %c%c\n",
rd->alpha2[0], rd->alpha2[1]);
print_rd_rules(rd);
}
#ifdef CONFIG_CFG80211_REG_DEBUG
static void reg_country_ie_process_debug(
const struct ieee80211_regdomain *rd,
const struct ieee80211_regdomain *country_ie_regdomain,
const struct ieee80211_regdomain *intersected_rd)
{
printk(KERN_DEBUG "cfg80211: Received country IE:\n");
print_regdomain_info(country_ie_regdomain);
printk(KERN_DEBUG "cfg80211: CRDA thinks this should applied:\n");
print_regdomain_info(rd);
if (intersected_rd) {
printk(KERN_DEBUG "cfg80211: We intersect both of these "
"and get:\n");
print_regdomain_info(intersected_rd);
return;
}
printk(KERN_DEBUG "cfg80211: Intersection between both failed\n");
}
#else
static inline void reg_country_ie_process_debug(
const struct ieee80211_regdomain *rd,
const struct ieee80211_regdomain *country_ie_regdomain,
const struct ieee80211_regdomain *intersected_rd)
{
}
#endif
/* Takes ownership of rd only if it doesn't fail */
static int __set_regdom(const struct ieee80211_regdomain *rd)
{
const struct ieee80211_regdomain *intersected_rd = NULL;
struct cfg80211_registered_device *drv = 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 (!is_old_static_regdom(cfg80211_regdomain) &&
!regdom_changes(rd->alpha2))
return -EINVAL;
}
/*
* Now lets set the regulatory domain, update all driver channels
* and finally inform them of what we have done, in case they want
* to review or adjust their own settings based on their own
* internal EEPROM data
*/
if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
return -EINVAL;
if (!is_valid_rd(rd)) {
printk(KERN_ERR "cfg80211: Invalid "
"regulatory domain detected:\n");
print_regdomain_info(rd);
return -EINVAL;
}
request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
if (!last_request->intersect) {
int r;
if (last_request->initiator != NL80211_REGDOM_SET_BY_DRIVER) {
reset_regdomains();
cfg80211_regdomain = rd;
return 0;
}
/*
* For a driver hint, lets copy the regulatory domain the
* driver wanted to the wiphy to deal with conflicts
*/
/*
* Userspace could have sent two replies with only
* one kernel request.
*/
if (request_wiphy->regd)
return -EALREADY;
r = reg_copy_regd(&request_wiphy->regd, rd);
if (r)
return r;
reset_regdomains();
cfg80211_regdomain = rd;
return 0;
}
/* Intersection requires a bit more work */
if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE) {
intersected_rd = regdom_intersect(rd, cfg80211_regdomain);
if (!intersected_rd)
return -EINVAL;
/*
* We can trash what CRDA provided now.
* However if a driver requested this specific regulatory
* domain we keep it for its private use
*/
if (last_request->initiator == NL80211_REGDOM_SET_BY_DRIVER)
request_wiphy->regd = rd;
else
kfree(rd);
rd = NULL;
reset_regdomains();
cfg80211_regdomain = intersected_rd;
return 0;
}
/*
* Country IE requests are handled a bit differently, we intersect
* the country IE rd with what CRDA believes that country should have
*/
/*
* Userspace could have sent two replies with only
* one kernel request. By the second reply we would have
* already processed and consumed the country_ie_regdomain.
*/
if (!country_ie_regdomain)
return -EALREADY;
BUG_ON(rd == country_ie_regdomain);
/*
* Intersect what CRDA returned and our what we
* had built from the Country IE received
*/
intersected_rd = regdom_intersect(rd, country_ie_regdomain);
reg_country_ie_process_debug(rd,
country_ie_regdomain,
intersected_rd);
kfree(country_ie_regdomain);
country_ie_regdomain = NULL;
if (!intersected_rd)
return -EINVAL;
drv = wiphy_to_dev(request_wiphy);
drv->country_ie_alpha2[0] = rd->alpha2[0];
drv->country_ie_alpha2[1] = rd->alpha2[1];
drv->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();
/* Note that this doesn't update the wiphys, this is done below */
r = __set_regdom(rd);
if (r) {
kfree(rd);
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);
return r;
}
/* Caller must hold cfg80211_mutex */
void reg_device_remove(struct wiphy *wiphy)
{
struct wiphy *request_wiphy = NULL;
assert_cfg80211_lock();
kfree(wiphy->regd);
if (last_request)
request_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
if (!request_wiphy || request_wiphy != wiphy)
return;
last_request->wiphy_idx = WIPHY_IDX_STALE;
last_request->country_ie_env = ENVIRON_ANY;
}
int regulatory_init(void)
{
int err = 0;
reg_pdev = platform_device_register_simple("regulatory", 0, NULL, 0);
if (IS_ERR(reg_pdev))
return PTR_ERR(reg_pdev);
spin_lock_init(&reg_requests_lock);
spin_lock_init(&reg_pending_beacons_lock);
#ifdef CONFIG_WIRELESS_OLD_REGULATORY
cfg80211_regdomain = static_regdom(ieee80211_regdom);
printk(KERN_INFO "cfg80211: Using static regulatory domain info\n");
print_regdomain_info(cfg80211_regdomain);
/*
* The old code still requests for a new regdomain and if
* you have CRDA you get it updated, otherwise you get
* stuck with the static values. Since "EU" is not a valid
* ISO / IEC 3166 alpha2 code we can't expect userpace to
* give us a regulatory domain for it. We need last_request
* iniitalized though so lets just send a request which we
* know will be ignored... this crap will be removed once
* OLD_REG dies.
*/
err = regulatory_hint_core(ieee80211_regdom);
#else
cfg80211_regdomain = cfg80211_world_regdom;
err = regulatory_hint_core(ieee80211_regdom);
#endif
if (err) {
if (err == -ENOMEM)
return err;
/*
* N.B. kobject_uevent_env() can fail mainly for when we're out
* memory which is handled and propagated appropriately above
* but it can also fail during a netlink_broadcast() or during
* early boot for call_usermodehelper(). For now treat these
* errors as non-fatal.
*/
printk(KERN_ERR "cfg80211: kobject_uevent_env() was unable "
"to call CRDA during init");
#ifdef CONFIG_CFG80211_REG_DEBUG
/* We want to find out exactly why when debugging */
WARN_ON(err);
#endif
}
return 0;
}
void regulatory_exit(void)
{
struct regulatory_request *reg_request, *tmp;
struct reg_beacon *reg_beacon, *btmp;
cancel_work_sync(&reg_work);
mutex_lock(&cfg80211_mutex);
reset_regdomains();
kfree(country_ie_regdomain);
country_ie_regdomain = NULL;
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(&cfg80211_mutex);
}