cfg80211: Add nl80211 event for deletion of a station entry

Indicate an NL80211_CMD_DEL_STATION event when a station entry in
mac80211 is deleted to match with the NL80211_CMD_NEW_STATION event
that is used when the entry was added. This is needed, e.g., to allow
user space to remove a peer from RSN IBSS Authenticator state machine
to avoid re-authentication and re-keying delays when the peer is not
reachable anymore.

Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

3 files changed, 46 insertions, 0 deletions

diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c
index aa5df8865ff7..16881fea4ce6 100644
--- a/net/wireless/mlme.c
+++ b/net/wireless/mlme.c
@@ -770,6 +770,15 @@ void cfg80211_new_sta(struct net_device *dev, const u8 *mac_addr,
 }
 EXPORT_SYMBOL(cfg80211_new_sta);
 
+void cfg80211_del_sta(struct net_device *dev, const u8 *mac_addr, gfp_t gfp)
+{
+        struct wiphy *wiphy = dev->ieee80211_ptr->wiphy;
+        struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
+
+        nl80211_send_sta_del_event(rdev, dev, mac_addr, gfp);
+}
+EXPORT_SYMBOL(cfg80211_del_sta);
+
 struct cfg80211_mgmt_registration {
         struct list_head list;
 
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 4ebce4284e9d..40c90fb461c4 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -5966,6 +5966,40 @@ void nl80211_send_sta_event(struct cfg80211_registered_device *rdev,
                                 nl80211_mlme_mcgrp.id, gfp);
 }
 
+void nl80211_send_sta_del_event(struct cfg80211_registered_device *rdev,
+                                struct net_device *dev, const u8 *mac_addr,
+                                gfp_t gfp)
+{
+        struct sk_buff *msg;
+        void *hdr;
+
+        msg = nlmsg_new(NLMSG_GOODSIZE, gfp);
+        if (!msg)
+                return;
+
+        hdr = nl80211hdr_put(msg, 0, 0, 0, NL80211_CMD_DEL_STATION);
+        if (!hdr) {
+                nlmsg_free(msg);
+                return;
+        }
+
+        NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, dev->ifindex);
+        NLA_PUT(msg, NL80211_ATTR_MAC, ETH_ALEN, mac_addr);
+
+        if (genlmsg_end(msg, hdr) < 0) {
+                nlmsg_free(msg);
+                return;
+        }
+
+        genlmsg_multicast_netns(wiphy_net(&rdev->wiphy), msg, 0,
+                                nl80211_mlme_mcgrp.id, gfp);
+        return;
+
+ nla_put_failure:
+        genlmsg_cancel(msg, hdr);
+        nlmsg_free(msg);
+}
+
 int nl80211_send_mgmt(struct cfg80211_registered_device *rdev,
                       struct net_device *netdev, u32 nlpid,
                       int freq, const u8 *buf, size_t len, gfp_t gfp)
diff --git a/net/wireless/nl80211.h b/net/wireless/nl80211.h
index e3f7fa886966..dcac5cd6f017 100644
--- a/net/wireless/nl80211.h
+++ b/net/wireless/nl80211.h
@@ -79,6 +79,9 @@ void nl80211_send_remain_on_channel_cancel(
 void nl80211_send_sta_event(struct cfg80211_registered_device *rdev,
                             struct net_device *dev, const u8 *mac_addr,
                             struct station_info *sinfo, gfp_t gfp);
+void nl80211_send_sta_del_event(struct cfg80211_registered_device *rdev,
+                                struct net_device *dev, const u8 *mac_addr,
+                                gfp_t gfp);
 
 int nl80211_send_mgmt(struct cfg80211_registered_device *rdev,
                       struct net_device *netdev, u32 nlpid, int freq,