move tcp.PickPort to its own package

testing/scenarios/command_test.go

@@ -37,8 +37,8 @@ func TestCommanderRemoveHandler(t *testing.T) {
 	assert(err, IsNil)
 	defer tcpServer.Close()
 
-	clientPort := pickPort()
-	cmdPort := pickPort()
+	clientPort := tcp.PickPort()
+	cmdPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&commander.Config{
@@ -150,8 +150,8 @@ func TestCommanderAddRemoveUser(t *testing.T) {
 	u1 := protocol.NewID(uuid.New())
 	u2 := protocol.NewID(uuid.New())
 
-	cmdPort := pickPort()
-	serverPort := pickPort()
+	cmdPort := tcp.PickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&commander.Config{
@@ -219,7 +219,7 @@ func TestCommanderAddRemoveUser(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&policy.Config{

testing/scenarios/common.go

@@ -22,15 +22,6 @@ import (
 	"v2ray.com/core/common/serial"
 )
 
-func pickPort() net.Port {
-	listener, err := net.Listen("tcp4", "127.0.0.1:0")
-	common.Must(err)
-	defer listener.Close()
-
-	addr := listener.Addr().(*net.TCPAddr)
-	return net.Port(addr.Port)
-}
-
 func xor(b []byte) []byte {
 	r := make([]byte, len(b))
 	for i, v := range b {

testing/scenarios/dns_test.go

@@ -28,7 +28,7 @@ func TestResolveIP(t *testing.T) {
 	assert(err, IsNil)
 	defer tcpServer.Close()
 
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&dns.Config{

testing/scenarios/dokodemo_test.go

@@ -32,7 +32,7 @@ func TestDokodemoTCP(t *testing.T) {
 	defer tcpServer.Close()
 
 	userID := protocol.NewID(uuid.New())
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -64,7 +64,7 @@ func TestDokodemoTCP(t *testing.T) {
 		},
 	}
 
-	clientPort := uint32(pickPort())
+	clientPort := uint32(tcp.PickPort())
 	clientPortRange := uint32(5)
 	clientConfig := &core.Config{
 		App: []*serial.TypedMessage{
@@ -145,7 +145,7 @@ func TestDokodemoUDP(t *testing.T) {
 	defer udpServer.Close()
 
 	userID := protocol.NewID(uuid.New())
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -171,7 +171,7 @@ func TestDokodemoUDP(t *testing.T) {
 		},
 	}
 
-	clientPort := uint32(pickPort())
+	clientPort := uint32(tcp.PickPort())
 	clientPortRange := uint32(5)
 	clientConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{

testing/scenarios/feature_test.go

@@ -46,7 +46,7 @@ func TestPassiveConnection(t *testing.T) {
 	assert(err, IsNil)
 	defer tcpServer.Close()
 
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -117,7 +117,7 @@ func TestProxy(t *testing.T) {
 	defer tcpServer.Close()
 
 	serverUserID := protocol.NewID(uuid.New())
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -144,7 +144,7 @@ func TestProxy(t *testing.T) {
 	}
 
 	proxyUserID := protocol.NewID(uuid.New())
-	proxyPort := pickPort()
+	proxyPort := tcp.PickPort()
 	proxyConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -170,7 +170,7 @@ func TestProxy(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -265,7 +265,7 @@ func TestProxyOverKCP(t *testing.T) {
 	defer tcpServer.Close()
 
 	serverUserID := protocol.NewID(uuid.New())
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -295,7 +295,7 @@ func TestProxyOverKCP(t *testing.T) {
 	}
 
 	proxyUserID := protocol.NewID(uuid.New())
-	proxyPort := pickPort()
+	proxyPort := tcp.PickPort()
 	proxyConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -326,7 +326,7 @@ func TestProxyOverKCP(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -430,8 +430,8 @@ func TestBlackhole(t *testing.T) {
 	assert(err, IsNil)
 	defer tcpServer2.Close()
 
-	serverPort := pickPort()
-	serverPort2 := pickPort()
+	serverPort := tcp.PickPort()
+	serverPort2 := tcp.PickPort()
 	serverConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -521,7 +521,7 @@ func TestForward(t *testing.T) {
 	assert(err, IsNil)
 	defer tcpServer.Close()
 
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -587,7 +587,7 @@ func TestUDPConnection(t *testing.T) {
 	assert(err, IsNil)
 	defer udpServer.Close()
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -663,8 +663,8 @@ func TestUDPConnection(t *testing.T) {
 func TestDomainSniffing(t *testing.T) {
 	assert := With(t)
 
-	sniffingPort := pickPort()
-	httpPort := pickPort()
+	sniffingPort := tcp.PickPort()
+	httpPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -764,7 +764,7 @@ func TestDialV2Ray(t *testing.T) {
 	defer tcpServer.Close()
 
 	userID := protocol.NewID(uuid.New())
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{

testing/scenarios/http_test.go

@@ -26,7 +26,7 @@ import (
 func TestHttpConformance(t *testing.T) {
 	assert := With(t)
 
-	httpServerPort := pickPort()
+	httpServerPort := tcp.PickPort()
 	httpServer := &v2httptest.Server{
 		Port:        httpServerPort,
 		PathHandler: make(map[string]http.HandlerFunc),
@@ -35,7 +35,7 @@ func TestHttpConformance(t *testing.T) {
 	assert(err, IsNil)
 	defer httpServer.Close()
 
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -90,7 +90,7 @@ func TestHttpConnectMethod(t *testing.T) {
 	assert(err, IsNil)
 	defer tcpServer.Close()
 
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -146,7 +146,7 @@ func TestHttpConnectMethod(t *testing.T) {
 func TestHttpPost(t *testing.T) {
 	assert := With(t)
 
-	httpServerPort := pickPort()
+	httpServerPort := tcp.PickPort()
 	httpServer := &v2httptest.Server{
 		Port: httpServerPort,
 		PathHandler: map[string]http.HandlerFunc{
@@ -169,7 +169,7 @@ func TestHttpPost(t *testing.T) {
 	assert(err, IsNil)
 	defer httpServer.Close()
 
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -226,7 +226,7 @@ func setProxyBasicAuth(req *http.Request, user, pass string) {
 func TestHttpBasicAuth(t *testing.T) {
 	assert := With(t)
 
-	httpServerPort := pickPort()
+	httpServerPort := tcp.PickPort()
 	httpServer := &v2httptest.Server{
 		Port:        httpServerPort,
 		PathHandler: make(map[string]http.HandlerFunc),
@@ -235,7 +235,7 @@ func TestHttpBasicAuth(t *testing.T) {
 	assert(err, IsNil)
 	defer httpServer.Close()
 
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{

testing/scenarios/policy_test.go

@@ -17,6 +17,7 @@ import (
 	"v2ray.com/core/proxy/vmess"
 	"v2ray.com/core/proxy/vmess/inbound"
 	"v2ray.com/core/proxy/vmess/outbound"
+	"v2ray.com/core/testing/servers/tcp"
 	. "v2ray.com/ext/assert"
 )
 
@@ -49,7 +50,7 @@ func TestVMessClosing(t *testing.T) {
 	dest := net.DestinationFromAddr(tcpServer.Addr())
 
 	userID := protocol.NewID(uuid.New())
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&policy.Config{
@@ -88,7 +89,7 @@ func TestVMessClosing(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&policy.Config{

testing/scenarios/shadowsocks_test.go

@@ -41,7 +41,7 @@ func TestShadowsocksAES256TCP(t *testing.T) {
 		Ota:        shadowsocks.Account_Enabled,
 	})
 
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -70,7 +70,7 @@ func TestShadowsocksAES256TCP(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -159,7 +159,7 @@ func TestShadowsocksAES128UDP(t *testing.T) {
 		Ota:        shadowsocks.Account_Enabled,
 	})
 
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -189,7 +189,7 @@ func TestShadowsocksAES128UDP(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -278,7 +278,7 @@ func TestShadowsocksChacha20TCP(t *testing.T) {
 		Ota:        shadowsocks.Account_Enabled,
 	})
 
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -307,7 +307,7 @@ func TestShadowsocksChacha20TCP(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -395,7 +395,7 @@ func TestShadowsocksAES256GCMTCP(t *testing.T) {
 		CipherType: shadowsocks.CipherType_AES_256_GCM,
 	})
 
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -424,7 +424,7 @@ func TestShadowsocksAES256GCMTCP(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -512,7 +512,7 @@ func TestShadowsocksAES128GCMUDP(t *testing.T) {
 		CipherType: shadowsocks.CipherType_AES_128_GCM,
 	})
 
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -542,7 +542,7 @@ func TestShadowsocksAES128GCMUDP(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -630,7 +630,7 @@ func TestShadowsocksAES256GCMConformance(t *testing.T) {
 		CipherType: shadowsocks.CipherType_AES_256_GCM,
 	})
 
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -708,7 +708,7 @@ func TestShadowsocksChacha20Poly1305UDPConformance(t *testing.T) {
 		CipherType: shadowsocks.CipherType_CHACHA20_POLY1305,
 	})
 
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -791,7 +791,7 @@ func TestShadowsocksChacha20Conformance(t *testing.T) {
 		Ota:        shadowsocks.Account_Disabled,
 	})
 
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{

testing/scenarios/socks_test.go

@@ -28,7 +28,7 @@ func TestSocksBridgeTCP(t *testing.T) {
 	assert(err, IsNil)
 	defer tcpServer.Close()
 
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -53,7 +53,7 @@ func TestSocksBridgeTCP(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -125,7 +125,7 @@ func TestSocksBridageUDP(t *testing.T) {
 	assert(err, IsNil)
 	defer udpServer.Close()
 
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -150,7 +150,7 @@ func TestSocksBridageUDP(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -222,8 +222,8 @@ func TestSocksConformance(t *testing.T) {
 	assert(err, IsNil)
 	defer tcpServer.Close()
 
-	authPort := pickPort()
-	noAuthPort := pickPort()
+	authPort := tcp.PickPort()
+	noAuthPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{

testing/scenarios/tls_test.go

@@ -36,7 +36,7 @@ func TestSimpleTLSConnection(t *testing.T) {
 	defer tcpServer.Close()
 
 	userID := protocol.NewID(uuid.New())
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -70,7 +70,7 @@ func TestSimpleTLSConnection(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -185,7 +185,7 @@ func TestTLSOverKCP(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -266,7 +266,7 @@ func TestTLSOverWebSocket(t *testing.T) {
 	defer tcpServer.Close()
 
 	userID := protocol.NewID(uuid.New())
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -301,7 +301,7 @@ func TestTLSOverWebSocket(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{

testing/scenarios/transport_test.go

@@ -33,7 +33,7 @@ func TestHttpConnectionHeader(t *testing.T) {
 	defer tcpServer.Close()
 
 	userID := protocol.NewID(uuid.New())
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{
@@ -69,7 +69,7 @@ func TestHttpConnectionHeader(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		Inbound: []*core.InboundHandlerConfig{
 			{

testing/scenarios/vmess_test.go

@@ -36,7 +36,7 @@ func TestVMessDynamicPort(t *testing.T) {
 	defer tcpServer.Close()
 
 	userID := protocol.NewID(uuid.New())
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -91,7 +91,7 @@ func TestVMessDynamicPort(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -171,7 +171,7 @@ func TestVMessGCM(t *testing.T) {
 	defer tcpServer.Close()
 
 	userID := protocol.NewID(uuid.New())
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -204,7 +204,7 @@ func TestVMessGCM(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -294,7 +294,7 @@ func TestVMessGCMUDP(t *testing.T) {
 	defer udpServer.Close()
 
 	userID := protocol.NewID(uuid.New())
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -327,7 +327,7 @@ func TestVMessGCMUDP(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -427,7 +427,7 @@ func TestVMessChacha20(t *testing.T) {
 	defer tcpServer.Close()
 
 	userID := protocol.NewID(uuid.New())
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -460,7 +460,7 @@ func TestVMessChacha20(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -550,7 +550,7 @@ func TestVMessNone(t *testing.T) {
 	defer tcpServer.Close()
 
 	userID := protocol.NewID(uuid.New())
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -583,7 +583,7 @@ func TestVMessNone(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -711,7 +711,7 @@ func TestVMessKCP(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -808,7 +808,7 @@ func TestVMessIPv6(t *testing.T) {
 	defer tcpServer.Close()
 
 	userID := protocol.NewID(uuid.New())
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -841,7 +841,7 @@ func TestVMessIPv6(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -923,7 +923,7 @@ func TestVMessGCMMux(t *testing.T) {
 	defer tcpServer.Close()
 
 	userID := protocol.NewID(uuid.New())
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -956,7 +956,7 @@ func TestVMessGCMMux(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -1065,7 +1065,7 @@ func TestVMessGCMMuxUDP(t *testing.T) {
 	defer udpServer.Close()
 
 	userID := protocol.NewID(uuid.New())
-	serverPort := pickPort()
+	serverPort := tcp.PickPort()
 	serverConfig := &core.Config{
 		App: []*serial.TypedMessage{
 			serial.ToTypedMessage(&log.Config{
@@ -1098,7 +1098,7 @@ func TestVMessGCMMuxUDP(t *testing.T) {
 		},
 	}
 
-	clientPort := pickPort()
+	clientPort := tcp.PickPort()
 	clientUDPPort := udp.PickPort()
 	clientConfig := &core.Config{
 		App: []*serial.TypedMessage{

testing/servers/tcp/port.go

@@ -0,0 +1,16 @@
+package tcp
+
+import (
+	"v2ray.com/core/common"
+	"v2ray.com/core/common/net"
+)
+
+// PickPort returns an unused TCP port in the system. The port returned is highly likely to be unused, but not guaranteed.
+func PickPort() net.Port {
+	listener, err := net.Listen("tcp4", "127.0.0.1:0")
+	common.Must(err)
+	defer listener.Close()
+
+	addr := listener.Addr().(*net.TCPAddr)
+	return net.Port(addr.Port)
+}

testing/servers/udp/port.go

@@ -5,6 +5,7 @@ import (
 	"v2ray.com/core/common/net"
 )
 
+// PickPort returns an unused UDP port in the system. The port returned is highly likely to be unused, but not guaranteed.
 func PickPort() net.Port {
 	conn, err := net.ListenUDP("udp4", &net.UDPAddr{
 		IP:   net.LocalHostIP.IP(),