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>

1 files changed, 151 insertions, 0 deletions

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 77880ba8..1221d72 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -18,6 +18,7 @@
 #include <net/cfg80211.h>
 #include "core.h"
 #include "nl80211.h"
+#include "reg.h"
 
 /* the netlink family */
 static struct genl_family nl80211_fam = {
@@ -88,6 +89,9 @@ static struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] __read_mostly = {
 				.len = IEEE80211_MAX_MESH_ID_LEN },
 	[NL80211_ATTR_MPATH_NEXT_HOP] = { .type = NLA_U32 },
 
+	[NL80211_ATTR_REG_ALPHA2] = { .type = NLA_STRING, .len = 2 },
+	[NL80211_ATTR_REG_RULES] = { .type = NLA_NESTED },
+
 	[NL80211_ATTR_BSS_CTS_PROT] = { .type = NLA_U8 },
 	[NL80211_ATTR_BSS_SHORT_PREAMBLE] = { .type = NLA_U8 },
 	[NL80211_ATTR_BSS_SHORT_SLOT_TIME] = { .type = NLA_U8 },
@@ -1599,6 +1603,141 @@ static int nl80211_set_bss(struct sk_buff *skb, struct genl_info *info)
 	return err;
 }
 
+static const struct nla_policy
+	reg_rule_policy[NL80211_REG_RULE_ATTR_MAX + 1] = {
+	[NL80211_ATTR_REG_RULE_FLAGS]		= { .type = NLA_U32 },
+	[NL80211_ATTR_FREQ_RANGE_START]		= { .type = NLA_U32 },
+	[NL80211_ATTR_FREQ_RANGE_END]		= { .type = NLA_U32 },
+	[NL80211_ATTR_FREQ_RANGE_MAX_BW]	= { .type = NLA_U32 },
+	[NL80211_ATTR_POWER_RULE_MAX_ANT_GAIN]	= { .type = NLA_U32 },
+	[NL80211_ATTR_POWER_RULE_MAX_EIRP]	= { .type = NLA_U32 },
+};
+
+static int parse_reg_rule(struct nlattr *tb[],
+	struct ieee80211_reg_rule *reg_rule)
+{
+	struct ieee80211_freq_range *freq_range = &reg_rule->freq_range;
+	struct ieee80211_power_rule *power_rule = &reg_rule->power_rule;
+
+	if (!tb[NL80211_ATTR_REG_RULE_FLAGS])
+		return -EINVAL;
+	if (!tb[NL80211_ATTR_FREQ_RANGE_START])
+		return -EINVAL;
+	if (!tb[NL80211_ATTR_FREQ_RANGE_END])
+		return -EINVAL;
+	if (!tb[NL80211_ATTR_FREQ_RANGE_MAX_BW])
+		return -EINVAL;
+	if (!tb[NL80211_ATTR_POWER_RULE_MAX_EIRP])
+		return -EINVAL;
+
+	reg_rule->flags = nla_get_u32(tb[NL80211_ATTR_REG_RULE_FLAGS]);
+
+	freq_range->start_freq_khz =
+		nla_get_u32(tb[NL80211_ATTR_FREQ_RANGE_START]);
+	freq_range->end_freq_khz =
+		nla_get_u32(tb[NL80211_ATTR_FREQ_RANGE_END]);
+	freq_range->max_bandwidth_khz =
+		nla_get_u32(tb[NL80211_ATTR_FREQ_RANGE_MAX_BW]);
+
+	power_rule->max_eirp =
+		nla_get_u32(tb[NL80211_ATTR_POWER_RULE_MAX_EIRP]);
+
+	if (tb[NL80211_ATTR_POWER_RULE_MAX_ANT_GAIN])
+		power_rule->max_antenna_gain =
+			nla_get_u32(tb[NL80211_ATTR_POWER_RULE_MAX_ANT_GAIN]);
+
+	return 0;
+}
+
+static int nl80211_req_set_reg(struct sk_buff *skb, struct genl_info *info)
+{
+	int r;
+	char *data = NULL;
+
+	if (!info->attrs[NL80211_ATTR_REG_ALPHA2])
+		return -EINVAL;
+
+	data = nla_data(info->attrs[NL80211_ATTR_REG_ALPHA2]);
+
+#ifdef CONFIG_WIRELESS_OLD_REGULATORY
+	/* We ignore world regdom requests with the old regdom setup */
+	if (is_world_regdom(data))
+		return -EINVAL;
+#endif
+	mutex_lock(&cfg80211_drv_mutex);
+	r = __regulatory_hint(NULL, REGDOM_SET_BY_USER, data, NULL);
+	mutex_unlock(&cfg80211_drv_mutex);
+	return r;
+}
+
+static int nl80211_set_reg(struct sk_buff *skb, struct genl_info *info)
+{
+	struct nlattr *tb[NL80211_REG_RULE_ATTR_MAX + 1];
+	struct nlattr *nl_reg_rule;
+	char *alpha2 = NULL;
+	int rem_reg_rules = 0, r = 0;
+	u32 num_rules = 0, rule_idx = 0, size_of_regd;
+	struct ieee80211_regdomain *rd = NULL;
+
+	if (!info->attrs[NL80211_ATTR_REG_ALPHA2])
+		return -EINVAL;
+
+	if (!info->attrs[NL80211_ATTR_REG_RULES])
+		return -EINVAL;
+
+	alpha2 = nla_data(info->attrs[NL80211_ATTR_REG_ALPHA2]);
+
+	nla_for_each_nested(nl_reg_rule, info->attrs[NL80211_ATTR_REG_RULES],
+			rem_reg_rules) {
+		num_rules++;
+		if (num_rules > NL80211_MAX_SUPP_REG_RULES)
+			goto bad_reg;
+	}
+
+	if (!reg_is_valid_request(alpha2))
+		return -EINVAL;
+
+	size_of_regd = sizeof(struct ieee80211_regdomain) +
+		(num_rules * sizeof(struct ieee80211_reg_rule));
+
+	rd = kzalloc(size_of_regd, GFP_KERNEL);
+	if (!rd)
+		return -ENOMEM;
+
+	rd->n_reg_rules = num_rules;
+	rd->alpha2[0] = alpha2[0];
+	rd->alpha2[1] = alpha2[1];
+
+	nla_for_each_nested(nl_reg_rule, info->attrs[NL80211_ATTR_REG_RULES],
+			rem_reg_rules) {
+		nla_parse(tb, NL80211_REG_RULE_ATTR_MAX,
+			nla_data(nl_reg_rule), nla_len(nl_reg_rule),
+			reg_rule_policy);
+		r = parse_reg_rule(tb, &rd->reg_rules[rule_idx]);
+		if (r)
+			goto bad_reg;
+
+		rule_idx++;
+
+		if (rule_idx > NL80211_MAX_SUPP_REG_RULES)
+			goto bad_reg;
+	}
+
+	BUG_ON(rule_idx != num_rules);
+
+	mutex_lock(&cfg80211_drv_mutex);
+	r = set_regdom(rd);
+	mutex_unlock(&cfg80211_drv_mutex);
+	if (r)
+		goto bad_reg;
+
+	return r;
+
+bad_reg:
+	kfree(rd);
+	return -EINVAL;
+}
+
 static struct genl_ops nl80211_ops[] = {
 	{
 		.cmd = NL80211_CMD_GET_WIPHY,
@@ -1736,6 +1875,18 @@ static struct genl_ops nl80211_ops[] = {
 		.policy = nl80211_policy,
 		.flags = GENL_ADMIN_PERM,
 	},
+	{
+		.cmd = NL80211_CMD_SET_REG,
+		.doit = nl80211_set_reg,
+		.policy = nl80211_policy,
+		.flags = GENL_ADMIN_PERM,
+	},
+	{
+		.cmd = NL80211_CMD_REQ_SET_REG,
+		.doit = nl80211_req_set_reg,
+		.policy = nl80211_policy,
+		.flags = GENL_ADMIN_PERM,
+	},
 };
 
 /* multicast groups */