Merge pull request #2376 from pradipd/NilIPToZero

Forcing a nil IP specified in PortBindings to IPv4zero (0.0.0.0).

libnetwork/drivers/windows/port_mapping.go

@@ -48,6 +48,12 @@ func allocatePort(portMapper *portmapper.PortMapper, bnd *types.PortBinding, con
 		err  error
 	)
 
+	// Windows does not support a host ip for port bindings (this is validated in ConvertPortBindings()).
+	// If the HostIP is nil, force it to be 0.0.0.0 for use as the key in portMapper.
+	if bnd.HostIP == nil {
+		bnd.HostIP = net.IPv4zero
+	}
+
 	// Store the container interface address in the operational binding
 	bnd.IP = containerIP
 

libnetwork/drivers/windows/windows.go

@@ -462,7 +462,7 @@ func ConvertPortBindings(portBindings []types.PortBinding) ([]json.RawMessage, e
 			return nil, fmt.Errorf("Windows does not support more than one host port in NAT settings")
 		}
 
-		if len(elem.HostIP) != 0 {
+		if len(elem.HostIP) != 0 && !elem.HostIP.IsUnspecified() {
 			return nil, fmt.Errorf("Windows does not support host IP addresses in NAT settings")
 		}