cfg80211/nl80211: Notify connection request failure in AP mode

In AP mode, when a station requests connection to an AP and if the
request is failed for particular reason, userspace is notified about the
failure through NL80211_CMD_CONN_FAILED command. Reason for the failure
is sent through the attribute NL80211_ATTR_CONN_FAILED_REASON.

Signed-off-by: Pandiyarajan Pitchaimuthu <c_ppitch@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 222189b6..f1047ae 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -8364,6 +8364,40 @@
 	nlmsg_free(msg);
 }
 
+void nl80211_send_conn_failed_event(struct cfg80211_registered_device *rdev,
+				    struct net_device *dev, const u8 *mac_addr,
+				    enum nl80211_connect_failed_reason reason,
+				    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_CONN_FAILED);
+	if (!hdr) {
+		nlmsg_free(msg);
+		return;
+	}
+
+	if (nla_put_u32(msg, NL80211_ATTR_IFINDEX, dev->ifindex) ||
+	    nla_put(msg, NL80211_ATTR_MAC, ETH_ALEN, mac_addr) ||
+	    nla_put_u32(msg, NL80211_ATTR_CONN_FAILED_REASON, reason))
+		goto nla_put_failure;
+
+	genlmsg_end(msg, hdr);
+
+	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);
+}
+
 static bool __nl80211_unexpected_frame(struct net_device *dev, u8 cmd,
 				       const u8 *addr, gfp_t gfp)
 {