linux/net/wireless/core.c
Luis R. Rodriguez b2e1b30290 cfg80211: Add new wireless regulatory infrastructure
This adds the new wireless regulatory infrastructure. The
main motiviation behind this was to centralize regulatory
code as each driver was implementing their own regulatory solution,
and to replace the initial centralized code we have where:

* only 3 regulatory domains are supported: US, JP and EU
* regulatory domains can only be changed through module parameter
* all rules were built statically in the kernel

We now have support for regulatory domains for many countries
and regulatory domains are now queried through a userspace agent
through udev allowing distributions to update regulatory rules
without updating the kernel.

Each driver can regulatory_hint() a regulatory domain
based on either their EEPROM mapped regulatory domain value to a
respective ISO/IEC 3166-1 country code or pass an internally built
regulatory domain. We also add support to let the user set the
regulatory domain through userspace in case of faulty EEPROMs to
further help compliance.

Support for world roaming will be added soon for cards capable of
this.

For more information see:

http://wireless.kernel.org/en/developers/Regulatory/CRDA

For now we leave an option to enable the old module parameter,
ieee80211_regdom, and to build the 3 old regdomains statically
(US, JP and EU). This option is CONFIG_WIRELESS_OLD_REGULATORY.
These old static definitions and the module parameter is being
scheduled for removal for 2.6.29. Note that if you use this
you won't make use of a world regulatory domain as its pointless.
If you leave this option enabled and if CRDA is present and you
use US or JP we will try to ask CRDA to update us a regulatory
domain for us.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-09-15 16:48:19 -04:00

605 lines
15 KiB
C

/*
* This is the linux wireless configuration interface.
*
* Copyright 2006-2008 Johannes Berg <johannes@sipsolutions.net>
*/
#include <linux/if.h>
#include <linux/module.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/list.h>
#include <linux/nl80211.h>
#include <linux/debugfs.h>
#include <linux/notifier.h>
#include <linux/device.h>
#include <linux/list.h>
#include <net/genetlink.h>
#include <net/cfg80211.h>
#include <net/wireless.h>
#include "nl80211.h"
#include "core.h"
#include "sysfs.h"
#include "reg.h"
/* name for sysfs, %d is appended */
#define PHY_NAME "phy"
MODULE_AUTHOR("Johannes Berg");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("wireless configuration support");
struct list_head regulatory_requests;
/* 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 */
struct ieee80211_regdomain *cfg80211_regdomain;
/* We keep a static world regulatory domain in case of the absence of CRDA */
const struct ieee80211_regdomain world_regdom = {
.n_reg_rules = 1,
.alpha2 = "00",
.reg_rules = {
REG_RULE(2402, 2472, 40, 6, 20,
NL80211_RRF_PASSIVE_SCAN |
NL80211_RRF_NO_IBSS),
}
};
#ifdef CONFIG_WIRELESS_OLD_REGULATORY
/* All this fucking static junk will be removed soon, so
* don't fucking count on it !@#$ */
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 */
const struct ieee80211_regdomain us_regdom = {
.n_reg_rules = 6,
.alpha2 = "US",
.reg_rules = {
/* IEEE 802.11b/g, channels 1..11 */
REG_RULE(2412-20, 2462+20, 40, 6, 27, 0),
/* IEEE 802.11a, channel 36 */
REG_RULE(5180-20, 5180+20, 40, 6, 23, 0),
/* IEEE 802.11a, channel 40 */
REG_RULE(5200-20, 5200+20, 40, 6, 23, 0),
/* IEEE 802.11a, channel 44 */
REG_RULE(5220-20, 5220+20, 40, 6, 23, 0),
/* IEEE 802.11a, channels 48..64 */
REG_RULE(5240-20, 5320+20, 40, 6, 23, 0),
/* IEEE 802.11a, channels 149..165, outdoor */
REG_RULE(5745-20, 5825+20, 40, 6, 30, 0),
}
};
const struct ieee80211_regdomain jp_regdom = {
.n_reg_rules = 3,
.alpha2 = "JP",
.reg_rules = {
/* IEEE 802.11b/g, channels 1..14 */
REG_RULE(2412-20, 2484+20, 40, 6, 20, 0),
/* IEEE 802.11a, channels 34..48 */
REG_RULE(5170-20, 5240+20, 40, 6, 20,
NL80211_RRF_PASSIVE_SCAN),
/* IEEE 802.11a, channels 52..64 */
REG_RULE(5260-20, 5320+20, 40, 6, 20,
NL80211_RRF_NO_IBSS |
NL80211_RRF_DFS),
}
};
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(2412-20, 2472+20, 40, 6, 20, 0),
/* IEEE 802.11a, channel 36 */
REG_RULE(5180-20, 5180+20, 40, 6, 23,
NL80211_RRF_PASSIVE_SCAN),
/* IEEE 802.11a, channel 40 */
REG_RULE(5200-20, 5200+20, 40, 6, 23,
NL80211_RRF_PASSIVE_SCAN),
/* IEEE 802.11a, channel 44 */
REG_RULE(5220-20, 5220+20, 40, 6, 23,
NL80211_RRF_PASSIVE_SCAN),
/* IEEE 802.11a, channels 48..64 */
REG_RULE(5240-20, 5320+20, 40, 6, 20,
NL80211_RRF_NO_IBSS |
NL80211_RRF_DFS),
/* IEEE 802.11a, channels 100..140 */
REG_RULE(5500-20, 5700+20, 40, 6, 30,
NL80211_RRF_NO_IBSS |
NL80211_RRF_DFS),
}
};
#endif
struct ieee80211_regdomain *cfg80211_world_regdom =
(struct ieee80211_regdomain *) &world_regdom;
LIST_HEAD(regulatory_requests);
DEFINE_MUTEX(cfg80211_reg_mutex);
/* RCU might be appropriate here since we usually
* only read the list, and that can happen quite
* often because we need to do it for each command */
LIST_HEAD(cfg80211_drv_list);
DEFINE_MUTEX(cfg80211_drv_mutex);
static int wiphy_counter;
/* for debugfs */
static struct dentry *ieee80211_debugfs_dir;
/* requires cfg80211_drv_mutex to be held! */
static struct cfg80211_registered_device *cfg80211_drv_by_wiphy(int wiphy)
{
struct cfg80211_registered_device *result = NULL, *drv;
list_for_each_entry(drv, &cfg80211_drv_list, list) {
if (drv->idx == wiphy) {
result = drv;
break;
}
}
return result;
}
/* requires cfg80211_drv_mutex to be held! */
static struct cfg80211_registered_device *
__cfg80211_drv_from_info(struct genl_info *info)
{
int ifindex;
struct cfg80211_registered_device *bywiphy = NULL, *byifidx = NULL;
struct net_device *dev;
int err = -EINVAL;
if (info->attrs[NL80211_ATTR_WIPHY]) {
bywiphy = cfg80211_drv_by_wiphy(
nla_get_u32(info->attrs[NL80211_ATTR_WIPHY]));
err = -ENODEV;
}
if (info->attrs[NL80211_ATTR_IFINDEX]) {
ifindex = nla_get_u32(info->attrs[NL80211_ATTR_IFINDEX]);
dev = dev_get_by_index(&init_net, ifindex);
if (dev) {
if (dev->ieee80211_ptr)
byifidx =
wiphy_to_dev(dev->ieee80211_ptr->wiphy);
dev_put(dev);
}
err = -ENODEV;
}
if (bywiphy && byifidx) {
if (bywiphy != byifidx)
return ERR_PTR(-EINVAL);
else
return bywiphy; /* == byifidx */
}
if (bywiphy)
return bywiphy;
if (byifidx)
return byifidx;
return ERR_PTR(err);
}
struct cfg80211_registered_device *
cfg80211_get_dev_from_info(struct genl_info *info)
{
struct cfg80211_registered_device *drv;
mutex_lock(&cfg80211_drv_mutex);
drv = __cfg80211_drv_from_info(info);
/* if it is not an error we grab the lock on
* it to assure it won't be going away while
* we operate on it */
if (!IS_ERR(drv))
mutex_lock(&drv->mtx);
mutex_unlock(&cfg80211_drv_mutex);
return drv;
}
struct cfg80211_registered_device *
cfg80211_get_dev_from_ifindex(int ifindex)
{
struct cfg80211_registered_device *drv = ERR_PTR(-ENODEV);
struct net_device *dev;
mutex_lock(&cfg80211_drv_mutex);
dev = dev_get_by_index(&init_net, ifindex);
if (!dev)
goto out;
if (dev->ieee80211_ptr) {
drv = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
mutex_lock(&drv->mtx);
} else
drv = ERR_PTR(-ENODEV);
dev_put(dev);
out:
mutex_unlock(&cfg80211_drv_mutex);
return drv;
}
void cfg80211_put_dev(struct cfg80211_registered_device *drv)
{
BUG_ON(IS_ERR(drv));
mutex_unlock(&drv->mtx);
}
int cfg80211_dev_rename(struct cfg80211_registered_device *rdev,
char *newname)
{
struct cfg80211_registered_device *drv;
int idx, taken = -1, result, digits;
mutex_lock(&cfg80211_drv_mutex);
/* prohibit calling the thing phy%d when %d is not its number */
sscanf(newname, PHY_NAME "%d%n", &idx, &taken);
if (taken == strlen(newname) && idx != rdev->idx) {
/* count number of places needed to print idx */
digits = 1;
while (idx /= 10)
digits++;
/*
* deny the name if it is phy<idx> where <idx> is printed
* without leading zeroes. taken == strlen(newname) here
*/
result = -EINVAL;
if (taken == strlen(PHY_NAME) + digits)
goto out_unlock;
}
/* Ignore nop renames */
result = 0;
if (strcmp(newname, dev_name(&rdev->wiphy.dev)) == 0)
goto out_unlock;
/* Ensure another device does not already have this name. */
list_for_each_entry(drv, &cfg80211_drv_list, list) {
result = -EINVAL;
if (strcmp(newname, dev_name(&drv->wiphy.dev)) == 0)
goto out_unlock;
}
/* this will only check for collisions in sysfs
* which is not even always compiled in.
*/
result = device_rename(&rdev->wiphy.dev, newname);
if (result)
goto out_unlock;
if (!debugfs_rename(rdev->wiphy.debugfsdir->d_parent,
rdev->wiphy.debugfsdir,
rdev->wiphy.debugfsdir->d_parent,
newname))
printk(KERN_ERR "cfg80211: failed to rename debugfs dir to %s!\n",
newname);
result = 0;
out_unlock:
mutex_unlock(&cfg80211_drv_mutex);
if (result == 0)
nl80211_notify_dev_rename(rdev);
return result;
}
/* exported functions */
struct wiphy *wiphy_new(struct cfg80211_ops *ops, int sizeof_priv)
{
struct cfg80211_registered_device *drv;
int alloc_size;
WARN_ON(!ops->add_key && ops->del_key);
WARN_ON(ops->add_key && !ops->del_key);
alloc_size = sizeof(*drv) + sizeof_priv;
drv = kzalloc(alloc_size, GFP_KERNEL);
if (!drv)
return NULL;
drv->ops = ops;
mutex_lock(&cfg80211_drv_mutex);
drv->idx = wiphy_counter;
/* now increase counter for the next device unless
* it has wrapped previously */
if (wiphy_counter >= 0)
wiphy_counter++;
mutex_unlock(&cfg80211_drv_mutex);
if (unlikely(drv->idx < 0)) {
/* ugh, wrapped! */
kfree(drv);
return NULL;
}
/* give it a proper name */
snprintf(drv->wiphy.dev.bus_id, BUS_ID_SIZE,
PHY_NAME "%d", drv->idx);
mutex_init(&drv->mtx);
mutex_init(&drv->devlist_mtx);
INIT_LIST_HEAD(&drv->netdev_list);
device_initialize(&drv->wiphy.dev);
drv->wiphy.dev.class = &ieee80211_class;
drv->wiphy.dev.platform_data = drv;
return &drv->wiphy;
}
EXPORT_SYMBOL(wiphy_new);
int wiphy_register(struct wiphy *wiphy)
{
struct cfg80211_registered_device *drv = wiphy_to_dev(wiphy);
int res;
enum ieee80211_band band;
struct ieee80211_supported_band *sband;
bool have_band = false;
int i;
u16 ifmodes = wiphy->interface_modes;
/* sanity check ifmodes */
WARN_ON(!ifmodes);
ifmodes &= ((1 << __NL80211_IFTYPE_AFTER_LAST) - 1) & ~1;
if (WARN_ON(ifmodes != wiphy->interface_modes))
wiphy->interface_modes = ifmodes;
/* sanity check supported bands/channels */
for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
sband = wiphy->bands[band];
if (!sband)
continue;
sband->band = band;
if (!sband->n_channels || !sband->n_bitrates) {
WARN_ON(1);
return -EINVAL;
}
for (i = 0; i < sband->n_channels; i++) {
sband->channels[i].orig_flags =
sband->channels[i].flags;
sband->channels[i].orig_mag =
sband->channels[i].max_antenna_gain;
sband->channels[i].orig_mpwr =
sband->channels[i].max_power;
sband->channels[i].band = band;
}
have_band = true;
}
if (!have_band) {
WARN_ON(1);
return -EINVAL;
}
/* check and set up bitrates */
ieee80211_set_bitrate_flags(wiphy);
/* set up regulatory info */
mutex_lock(&cfg80211_reg_mutex);
wiphy_update_regulatory(wiphy, REGDOM_SET_BY_CORE);
mutex_unlock(&cfg80211_reg_mutex);
mutex_lock(&cfg80211_drv_mutex);
res = device_add(&drv->wiphy.dev);
if (res)
goto out_unlock;
list_add(&drv->list, &cfg80211_drv_list);
/* add to debugfs */
drv->wiphy.debugfsdir =
debugfs_create_dir(wiphy_name(&drv->wiphy),
ieee80211_debugfs_dir);
res = 0;
out_unlock:
mutex_unlock(&cfg80211_drv_mutex);
return res;
}
EXPORT_SYMBOL(wiphy_register);
void wiphy_unregister(struct wiphy *wiphy)
{
struct cfg80211_registered_device *drv = wiphy_to_dev(wiphy);
/* protect the device list */
mutex_lock(&cfg80211_drv_mutex);
BUG_ON(!list_empty(&drv->netdev_list));
/*
* Try to grab drv->mtx. If a command is still in progress,
* hopefully the driver will refuse it since it's tearing
* down the device already. We wait for this command to complete
* before unlinking the item from the list.
* Note: as codified by the BUG_ON above we cannot get here if
* a virtual interface is still associated. Hence, we can only
* get to lock contention here if userspace issues a command
* that identified the hardware by wiphy index.
*/
mutex_lock(&drv->mtx);
/* unlock again before freeing */
mutex_unlock(&drv->mtx);
list_del(&drv->list);
device_del(&drv->wiphy.dev);
debugfs_remove(drv->wiphy.debugfsdir);
mutex_unlock(&cfg80211_drv_mutex);
}
EXPORT_SYMBOL(wiphy_unregister);
void cfg80211_dev_free(struct cfg80211_registered_device *drv)
{
mutex_destroy(&drv->mtx);
mutex_destroy(&drv->devlist_mtx);
kfree(drv);
}
void wiphy_free(struct wiphy *wiphy)
{
put_device(&wiphy->dev);
}
EXPORT_SYMBOL(wiphy_free);
static int cfg80211_netdev_notifier_call(struct notifier_block * nb,
unsigned long state,
void *ndev)
{
struct net_device *dev = ndev;
struct cfg80211_registered_device *rdev;
if (!dev->ieee80211_ptr)
return 0;
rdev = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
switch (state) {
case NETDEV_REGISTER:
mutex_lock(&rdev->devlist_mtx);
list_add(&dev->ieee80211_ptr->list, &rdev->netdev_list);
if (sysfs_create_link(&dev->dev.kobj, &rdev->wiphy.dev.kobj,
"phy80211")) {
printk(KERN_ERR "wireless: failed to add phy80211 "
"symlink to netdev!\n");
}
dev->ieee80211_ptr->netdev = dev;
mutex_unlock(&rdev->devlist_mtx);
break;
case NETDEV_UNREGISTER:
mutex_lock(&rdev->devlist_mtx);
if (!list_empty(&dev->ieee80211_ptr->list)) {
sysfs_remove_link(&dev->dev.kobj, "phy80211");
list_del_init(&dev->ieee80211_ptr->list);
}
mutex_unlock(&rdev->devlist_mtx);
break;
}
return 0;
}
static struct notifier_block cfg80211_netdev_notifier = {
.notifier_call = cfg80211_netdev_notifier_call,
};
#ifdef CONFIG_WIRELESS_OLD_REGULATORY
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;
}
#endif
static int cfg80211_init(void)
{
int err;
#ifdef CONFIG_WIRELESS_OLD_REGULATORY
cfg80211_regdomain =
(struct ieee80211_regdomain *) static_regdom(ieee80211_regdom);
/* Used during reset_regdomains_static() */
cfg80211_world_regdom = cfg80211_regdomain;
#else
cfg80211_regdomain =
(struct ieee80211_regdomain *) cfg80211_world_regdom;
#endif
err = wiphy_sysfs_init();
if (err)
goto out_fail_sysfs;
err = register_netdevice_notifier(&cfg80211_netdev_notifier);
if (err)
goto out_fail_notifier;
err = nl80211_init();
if (err)
goto out_fail_nl80211;
ieee80211_debugfs_dir = debugfs_create_dir("ieee80211", NULL);
err = regulatory_init();
if (err)
goto out_fail_reg;
#ifdef CONFIG_WIRELESS_OLD_REGULATORY
printk(KERN_INFO "cfg80211: Using old static regulatory domain:\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. We ignore "EU" code as
* that is not a valid ISO / IEC 3166 alpha2 */
if (ieee80211_regdom[0] != 'E' &&
ieee80211_regdom[1] != 'U')
err = __regulatory_hint(NULL, REGDOM_SET_BY_CORE,
ieee80211_regdom, NULL);
#else
err = __regulatory_hint(NULL, REGDOM_SET_BY_CORE, "00", NULL);
if (err)
printk(KERN_ERR "cfg80211: calling CRDA failed - "
"unable to update world regulatory domain, "
"using static definition\n");
#endif
return 0;
out_fail_reg:
debugfs_remove(ieee80211_debugfs_dir);
out_fail_nl80211:
unregister_netdevice_notifier(&cfg80211_netdev_notifier);
out_fail_notifier:
wiphy_sysfs_exit();
out_fail_sysfs:
return err;
}
subsys_initcall(cfg80211_init);
static void cfg80211_exit(void)
{
debugfs_remove(ieee80211_debugfs_dir);
nl80211_exit();
unregister_netdevice_notifier(&cfg80211_netdev_notifier);
wiphy_sysfs_exit();
regulatory_exit();
}
module_exit(cfg80211_exit);