@@ -2293,6 +2293,27 @@ func TestBuildExposeOrder(t *testing.T) {

 	logDone("build - expose order")

 }

+func TestBuildExposeUpperCaseProto(t *testing.T) {

+	name := "testbuildexposeuppercaseproto"

+	expected := "map[5678/udp:map[]]"

+	defer deleteImages(name)

+	_, err := buildImage(name,

+		`FROM scratch

+        EXPOSE 5678/UDP`,

+		true)

+	if err != nil {

+		t.Fatal(err)

+	}

+	res, err := inspectField(name, "Config.ExposedPorts")

+	if err != nil {

+		t.Fatal(err)

+	}

+	if res != expected {

+		t.Fatalf("Exposed ports %s, expected %s", res, expected)

+	}

+	logDone("build - expose port with upper case proto")

+}

+

 func TestBuildEmptyEntrypointInheritance(t *testing.T) {

 	name := "testbuildentrypointinheritance"

 	name2 := "testbuildentrypointinheritance2"

@@ -140,7 +140,7 @@ func ParsePortSpecs(ports []string) (map[Port]struct{}, map[Port][]PortBinding,

 			return nil, nil, fmt.Errorf("Invalid ranges specified for container and host Ports: %s and %s", containerPort, hostPort)

 		}

-		if !validateProto(proto) {

+		if !validateProto(strings.ToLower(proto)) {

 			return nil, nil, fmt.Errorf("Invalid proto: %s", proto)

 		}

@@ -149,7 +149,7 @@ func ParsePortSpecs(ports []string) (map[Port]struct{}, map[Port][]PortBinding,

 			if len(hostPort) > 0 {

 				hostPort = strconv.FormatUint(startHostPort+i, 10)

 			}

-			port := NewPort(proto, containerPort)

+			port := NewPort(strings.ToLower(proto), containerPort)

 			if _, exists := exposedPorts[port]; !exists {

 				exposedPorts[port] = struct{}{}

 			}