Ignore ipv4 link local addresses

1 files changed, 6 insertions, 3 deletions

diff --git a/cmd/web/main.go b/cmd/web/main.go
index d926a20..bbb7fb6 100644
--- a/cmd/web/main.go
+++ b/cmd/web/main.go
@@ -87,14 +87,17 @@ func isLocal(addr string) bool {
 }
 
 // getHostIP attempts to guess the IP address of the current machine and
-// returns that. Simply bails at the first non loopback IP returning that.
-// not ideal but it should work well enough most of the time
+// returns that. Simply bails at the first non sane looking IP and returns it.
+// Not ideal but it should work well enough most of the time
 func getHostIP() string {
 	iFaces, err := net.Interfaces()
 	if err != nil {
 		return "127.0.0.1"
 	}
 
+	// RFC 3927
+	_, ipv4LinkLocal, _ := net.ParseCIDR("169.254.0.0/16")
+
 	for _, iFace := range iFaces {
 		addrs, err := iFace.Addrs()
 		if err != nil {
@@ -107,7 +110,7 @@ func getHostIP() string {
 				continue
 			}
 
-			if n.IP.To4() != nil && !n.IP.IsLoopback() {
+			if n.IP.To4() != nil && !n.IP.IsLoopback() && !ipv4LinkLocal.Contains(n.IP.To4()) {
 				return n.IP.String()
 			}
 		}