cfg80211: add regulatory netlink multicast group

This allows us to send to userspace "regulatory" events.
For now we just send an event when we change regulatory domains.
We also notify userspace when devices are using their own custom
world roaming regulatory domains.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

4 files changed, 90 insertions, 1 deletions

diff --git a/net/wireless/core.c b/net/wireless/core.c
index c939f5e..17fe390 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -365,6 +365,17 @@ int wiphy_register(struct wiphy *wiphy)
 	if (IS_ERR(drv->wiphy.debugfsdir))
 		drv->wiphy.debugfsdir = NULL;
 
+	if (wiphy->custom_regulatory) {
+		struct regulatory_request request;
+
+		request.wiphy_idx = get_wiphy_idx(wiphy);
+		request.initiator = NL80211_REGDOM_SET_BY_DRIVER;
+		request.alpha2[0] = '9';
+		request.alpha2[1] = '9';
+
+		nl80211_send_reg_change_event(&request);
+	}
+
 	res = 0;
 out_unlock:
 	mutex_unlock(&cfg80211_mutex);
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 531bb67..8ac3d26 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -2739,6 +2739,9 @@ static struct genl_multicast_group nl80211_config_mcgrp = {
 static struct genl_multicast_group nl80211_scan_mcgrp = {
 	.name = "scan",
 };
+static struct genl_multicast_group nl80211_regulatory_mcgrp = {
+	.name = "regulatory",
+};
 
 /* notification functions */
 
@@ -2818,6 +2821,61 @@ void nl80211_send_scan_aborted(struct cfg80211_registered_device *rdev,
 	genlmsg_multicast(msg, 0, nl80211_scan_mcgrp.id, GFP_KERNEL);
 }
 
+/*
+ * This can happen on global regulatory changes or device specific settings
+ * based on custom world regulatory domains.
+ */
+void nl80211_send_reg_change_event(struct regulatory_request *request)
+{
+	struct sk_buff *msg;
+	void *hdr;
+
+	msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
+	if (!msg)
+		return;
+
+	hdr = nl80211hdr_put(msg, 0, 0, 0, NL80211_CMD_REG_CHANGE);
+	if (!hdr) {
+		nlmsg_free(msg);
+		return;
+	}
+
+	/* Userspace can always count this one always being set */
+	NLA_PUT_U8(msg, NL80211_ATTR_REG_INITIATOR, request->initiator);
+
+	if (request->alpha2[0] == '0' && request->alpha2[1] == '0')
+		NLA_PUT_U8(msg, NL80211_ATTR_REG_TYPE,
+			   NL80211_REGDOM_TYPE_WORLD);
+	else if (request->alpha2[0] == '9' && request->alpha2[1] == '9')
+		NLA_PUT_U8(msg, NL80211_ATTR_REG_TYPE,
+			   NL80211_REGDOM_TYPE_CUSTOM_WORLD);
+	else if ((request->alpha2[0] == '9' && request->alpha2[1] == '8') ||
+		 request->intersect)
+		NLA_PUT_U8(msg, NL80211_ATTR_REG_TYPE,
+			   NL80211_REGDOM_TYPE_INTERSECTION);
+	else {
+		NLA_PUT_U8(msg, NL80211_ATTR_REG_TYPE,
+			   NL80211_REGDOM_TYPE_COUNTRY);
+		NLA_PUT_STRING(msg, NL80211_ATTR_REG_ALPHA2, request->alpha2);
+	}
+
+	if (wiphy_idx_valid(request->wiphy_idx))
+		NLA_PUT_U32(msg, NL80211_ATTR_WIPHY, request->wiphy_idx);
+
+	if (genlmsg_end(msg, hdr) < 0) {
+		nlmsg_free(msg);
+		return;
+	}
+
+	genlmsg_multicast(msg, 0, nl80211_regulatory_mcgrp.id, GFP_KERNEL);
+
+	return;
+
+nla_put_failure:
+	genlmsg_cancel(msg, hdr);
+	nlmsg_free(msg);
+}
+
 /* initialisation/exit functions */
 
 int nl80211_init(void)
@@ -2842,6 +2900,10 @@ int nl80211_init(void)
 	if (err)
 		goto err_out;
 
+	err = genl_register_mc_group(&nl80211_fam, &nl80211_regulatory_mcgrp);
+	if (err)
+		goto err_out;
+
 	return 0;
  err_out:
 	genl_unregister_family(&nl80211_fam);
diff --git a/net/wireless/nl80211.h b/net/wireless/nl80211.h
index 69787b6..e65a3c3 100644
--- a/net/wireless/nl80211.h
+++ b/net/wireless/nl80211.h
@@ -11,6 +11,7 @@ extern void nl80211_send_scan_done(struct cfg80211_registered_device *rdev,
 				   struct net_device *netdev);
 extern void nl80211_send_scan_aborted(struct cfg80211_registered_device *rdev,
 				      struct net_device *netdev);
+extern void nl80211_send_reg_change_event(struct regulatory_request *request);
 #else
 static inline int nl80211_init(void)
 {
@@ -31,6 +32,10 @@ static inline void nl80211_send_scan_aborted(
 					struct cfg80211_registered_device *rdev,
 					struct net_device *netdev)
 {}
+static inline void
+nl80211_send_reg_change_event(struct regulatory_request *request)
+{
+}
 #endif /* CONFIG_NL80211 */
 
 #endif /* __NET_WIRELESS_NL80211_H */
diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index 68fde6d..eb8b8ed 100644
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c
@@ -41,6 +41,7 @@
 #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;
@@ -1403,8 +1404,16 @@ new_request:
 	pending_request = NULL;
 
 	/* When r == REG_INTERSECT we do need to call CRDA */
-	if (r < 0)
+	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;
+	}
 
 	/*
 	 * Note: When CONFIG_WIRELESS_OLD_REGULATORY is enabled
@@ -2084,6 +2093,8 @@ int set_regdom(const struct ieee80211_regdomain *rd)
 
 	print_regdomain(cfg80211_regdomain);
 
+	nl80211_send_reg_change_event(last_request);
+
 	return r;
 }