feat: client handshake info

app/cmd/client.go

@@ -402,8 +402,8 @@ func runClient(cmd *cobra.Command, args []string) {
 		logger.Fatal("failed to load client config", zap.Error(err))
 	}
 
-	c, err := client.NewReconnectableClient(hyConfig, func(c client.Client, count int) {
-		connectLog(count)
+	c, err := client.NewReconnectableClient(hyConfig, func(c client.Client, info *client.HandshakeInfo, count int) {
+		connectLog(info, count)
 		// On the client side, we start checking for updates after we successfully connect
 		// to the server, which, depending on whether lazy mode is enabled, may or may not
 		// be immediately after the client starts. We don't want the update check request
@@ -699,8 +699,11 @@ func (f *adaptiveConnFactory) New(addr net.Addr) (net.PacketConn, error) {
 	}
 }
 
-func connectLog(count int) {
-	logger.Info("connected to server", zap.Int("count", count))
+func connectLog(info *client.HandshakeInfo, count int) {
+	logger.Info("connected to server",
+		zap.Bool("udpEnabled", info.UDPEnabled),
+		zap.Uint64("tx", info.Tx),
+		zap.Int("count", count))
 }
 
 type socks5Logger struct{}

app/cmd/ping.go

@@ -42,13 +42,16 @@ func runPing(cmd *cobra.Command, args []string) {
 		logger.Fatal("failed to load client config", zap.Error(err))
 	}
 
-	c, err := client.NewClient(hyConfig)
+	c, info, err := client.NewClient(hyConfig)
 	if err != nil {
 		logger.Fatal("failed to initialize client", zap.Error(err))
 	}
 	defer c.Close()
+	logger.Info("connected to server",
+		zap.Bool("udpEnabled", info.UDPEnabled),
+		zap.Uint64("tx", info.Tx))
 
-	logger.Info("connecting", zap.String("address", addr))
+	logger.Info("connecting", zap.String("addr", addr))
 	start := time.Now()
 	conn, err := c.TCP(addr)
 	if err != nil {

core/client/client.go

@@ -34,17 +34,23 @@ type HyUDPConn interface {
 	Close() error
 }
 
-func NewClient(config *Config) (Client, error) {
+type HandshakeInfo struct {
+	UDPEnabled bool
+	Tx         uint64 // 0 if using BBR
+}
+
+func NewClient(config *Config) (Client, *HandshakeInfo, error) {
 	if err := config.verifyAndFill(); err != nil {
-		return nil, err
+		return nil, nil, err
 	}
 	c := &clientImpl{
 		config: config,
 	}
-	if err := c.connect(); err != nil {
-		return nil, err
+	info, err := c.connect()
+	if err != nil {
+		return nil, nil, err
 	}
-	return c, nil
+	return c, info, nil
 }
 
 type clientImpl struct {
@@ -56,10 +62,10 @@ type clientImpl struct {
 	udpSM *udpSessionManager
 }
 
-func (c *clientImpl) connect() error {
+func (c *clientImpl) connect() (*HandshakeInfo, error) {
 	pktConn, err := c.config.ConnFactory.New(c.config.ServerAddr)
 	if err != nil {
-		return err
+		return nil, err
 	}
 	// Convert config to TLS config & QUIC config
 	tlsConfig := &tls.Config{
@@ -113,22 +119,23 @@ func (c *clientImpl) connect() error {
 			_ = conn.CloseWithError(closeErrCodeProtocolError, "")
 		}
 		_ = pktConn.Close()
-		return coreErrs.ConnectError{Err: err}
+		return nil, coreErrs.ConnectError{Err: err}
 	}
 	if resp.StatusCode != protocol.StatusAuthOK {
 		_ = conn.CloseWithError(closeErrCodeProtocolError, "")
 		_ = pktConn.Close()
-		return coreErrs.AuthError{StatusCode: resp.StatusCode}
+		return nil, coreErrs.AuthError{StatusCode: resp.StatusCode}
 	}
 	// Auth OK
 	authResp := protocol.AuthResponseFromHeader(resp.Header)
+	var actualTx uint64
 	if authResp.RxAuto {
 		// Server asks client to use bandwidth detection,
 		// ignore local bandwidth config and use BBR
 		congestion.UseBBR(conn)
 	} else {
 		// actualTx = min(serverRx, clientTx)
-		actualTx := authResp.Rx
+		actualTx = authResp.Rx
 		if actualTx == 0 || actualTx > c.config.BandwidthConfig.MaxTx {
 			// Server doesn't have a limit, or our clientTx is smaller than serverRx
 			actualTx = c.config.BandwidthConfig.MaxTx
@@ -147,7 +154,10 @@ func (c *clientImpl) connect() error {
 	if authResp.UDPEnabled {
 		c.udpSM = newUDPSessionManager(&udpIOImpl{Conn: conn})
 	}
-	return nil
+	return &HandshakeInfo{
+		UDPEnabled: authResp.UDPEnabled,
+		Tx:         actualTx,
+	}, nil
 }
 
 // openStream wraps the stream with QStream, which handles Close() properly

core/client/reconnect.go

@@ -12,13 +12,14 @@ import (
 type reconnectableClientImpl struct {
 	config        *Config
 	client        Client
+	info          *HandshakeInfo
 	count         int
-	connectedFunc func(Client, int) // called when successfully connected
+	connectedFunc func(Client, *HandshakeInfo, int) // called when successfully connected
 	m             sync.Mutex
 	closed        bool // permanent close
 }
 
-func NewReconnectableClient(config *Config, connectedFunc func(Client, int), lazy bool) (Client, error) {
+func NewReconnectableClient(config *Config, connectedFunc func(Client, *HandshakeInfo, int), lazy bool) (Client, error) {
 	// Make sure we capture any error in config and return it here,
 	// so that the caller doesn't have to wait until the first call
 	// to TCP() or UDP() to get the error (when lazy is true).
@@ -42,13 +43,13 @@ func (rc *reconnectableClientImpl) reconnect() error {
 		_ = rc.client.Close()
 	}
 	var err error
-	rc.client, err = NewClient(rc.config)
+	rc.client, rc.info, err = NewClient(rc.config)
 	if err != nil {
 		return err
 	} else {
 		rc.count++
 		if rc.connectedFunc != nil {
-			rc.connectedFunc(rc, rc.count)
+			rc.connectedFunc(rc, rc.info, rc.count)
 		}
 		return nil
 	}

core/internal/integration_tests/close_test.go

@@ -34,7 +34,7 @@ func TestClientServerTCPClose(t *testing.T) {
 	go s.Serve()
 
 	// Create client
-	c, err := client.NewClient(&client.Config{
+	c, _, err := client.NewClient(&client.Config{
 		ServerAddr: udpAddr,
 		TLSConfig:  client.TLSConfig{InsecureSkipVerify: true},
 	})
@@ -116,7 +116,7 @@ func TestClientServerUDPIdleTimeout(t *testing.T) {
 	go s.Serve()
 
 	// Create client
-	c, err := client.NewClient(&client.Config{
+	c, _, err := client.NewClient(&client.Config{
 		ServerAddr: udpAddr,
 		TLSConfig:  client.TLSConfig{InsecureSkipVerify: true},
 	})
@@ -194,7 +194,7 @@ func TestClientServerClientShutdown(t *testing.T) {
 	go s.Serve()
 
 	// Create client
-	c, err := client.NewClient(&client.Config{
+	c, _, err := client.NewClient(&client.Config{
 		ServerAddr: udpAddr,
 		TLSConfig:  client.TLSConfig{InsecureSkipVerify: true},
 	})
@@ -223,7 +223,7 @@ func TestClientServerServerShutdown(t *testing.T) {
 	go s.Serve()
 
 	// Create client
-	c, err := client.NewClient(&client.Config{
+	c, _, err := client.NewClient(&client.Config{
 		ServerAddr: udpAddr,
 		TLSConfig:  client.TLSConfig{InsecureSkipVerify: true},
 		QUICConfig: client.QUICConfig{

core/internal/integration_tests/smoke_test.go

@@ -19,7 +19,7 @@ import (
 // TestClientNoServer tests how the client handles a server address it cannot connect to.
 // NewClient should return a ConnectError.
 func TestClientNoServer(t *testing.T) {
-	c, err := client.NewClient(&client.Config{
+	c, _, err := client.NewClient(&client.Config{
 		ServerAddr: &net.UDPAddr{IP: net.IPv4(127, 0, 0, 1), Port: 55666},
 	})
 	assert.Nil(t, c)
@@ -46,7 +46,7 @@ func TestClientServerBadAuth(t *testing.T) {
 	go s.Serve()
 
 	// Create client
-	c, err := client.NewClient(&client.Config{
+	c, _, err := client.NewClient(&client.Config{
 		ServerAddr: udpAddr,
 		Auth:       "badpassword",
 		TLSConfig:  client.TLSConfig{InsecureSkipVerify: true},
@@ -75,7 +75,7 @@ func TestClientServerUDPDisabled(t *testing.T) {
 	go s.Serve()
 
 	// Create client
-	c, err := client.NewClient(&client.Config{
+	c, _, err := client.NewClient(&client.Config{
 		ServerAddr: udpAddr,
 		TLSConfig:  client.TLSConfig{InsecureSkipVerify: true},
 	})
@@ -113,7 +113,7 @@ func TestClientServerTCPEcho(t *testing.T) {
 	go echoServer.Serve()
 
 	// Create client
-	c, err := client.NewClient(&client.Config{
+	c, _, err := client.NewClient(&client.Config{
 		ServerAddr: udpAddr,
 		TLSConfig:  client.TLSConfig{InsecureSkipVerify: true},
 	})
@@ -160,7 +160,7 @@ func TestClientServerUDPEcho(t *testing.T) {
 	go echoServer.Serve()
 
 	// Create client
-	c, err := client.NewClient(&client.Config{
+	c, _, err := client.NewClient(&client.Config{
 		ServerAddr: udpAddr,
 		TLSConfig:  client.TLSConfig{InsecureSkipVerify: true},
 	})
@@ -181,3 +181,100 @@ func TestClientServerUDPEcho(t *testing.T) {
 	assert.Equal(t, sData, rData)
 	assert.Equal(t, echoAddr, rAddr)
 }
+
+// TestClientServerHandshakeInfo tests that the client returns the correct handshake info.
+func TestClientServerHandshakeInfo(t *testing.T) {
+	// Create server 1, UDP enabled, unlimited bandwidth
+	udpConn, udpAddr, err := serverConn()
+	assert.NoError(t, err)
+	auth := mocks.NewMockAuthenticator(t)
+	auth.EXPECT().Authenticate(mock.Anything, mock.Anything, mock.Anything).Return(true, "nobody")
+	s, err := server.NewServer(&server.Config{
+		TLSConfig:     serverTLSConfig(),
+		Conn:          udpConn,
+		Authenticator: auth,
+	})
+	assert.NoError(t, err)
+	go s.Serve()
+
+	// Create client 1, with specified tx bandwidth
+	c, info, err := client.NewClient(&client.Config{
+		ServerAddr: udpAddr,
+		TLSConfig:  client.TLSConfig{InsecureSkipVerify: true},
+		BandwidthConfig: client.BandwidthConfig{
+			MaxTx: 123456,
+		},
+	})
+	assert.NoError(t, err)
+	assert.Equal(t, &client.HandshakeInfo{
+		UDPEnabled: true,
+		Tx:         123456,
+	}, info)
+
+	// Close server 1 and client 1
+	_ = s.Close()
+	_ = c.Close()
+
+	// Create server 2, UDP disabled, limited rx bandwidth
+	udpConn, udpAddr, err = serverConn()
+	assert.NoError(t, err)
+	s, err = server.NewServer(&server.Config{
+		TLSConfig: serverTLSConfig(),
+		Conn:      udpConn,
+		BandwidthConfig: server.BandwidthConfig{
+			MaxRx: 100000,
+		},
+		DisableUDP:    true,
+		Authenticator: auth,
+	})
+	assert.NoError(t, err)
+	go s.Serve()
+
+	// Create client 2, with specified tx bandwidth
+	c, info, err = client.NewClient(&client.Config{
+		ServerAddr: udpAddr,
+		TLSConfig:  client.TLSConfig{InsecureSkipVerify: true},
+		BandwidthConfig: client.BandwidthConfig{
+			MaxTx: 123456,
+		},
+	})
+	assert.NoError(t, err)
+	assert.Equal(t, &client.HandshakeInfo{
+		UDPEnabled: false,
+		Tx:         100000,
+	}, info)
+
+	// Close server 2 and client 2
+	_ = s.Close()
+	_ = c.Close()
+
+	// Create server 3, UDP enabled, ignore client bandwidth
+	udpConn, udpAddr, err = serverConn()
+	assert.NoError(t, err)
+	s, err = server.NewServer(&server.Config{
+		TLSConfig:             serverTLSConfig(),
+		Conn:                  udpConn,
+		IgnoreClientBandwidth: true,
+		Authenticator:         auth,
+	})
+	assert.NoError(t, err)
+	go s.Serve()
+
+	// Create client 3, with specified tx bandwidth
+	c, info, err = client.NewClient(&client.Config{
+		ServerAddr: udpAddr,
+		TLSConfig:  client.TLSConfig{InsecureSkipVerify: true},
+		BandwidthConfig: client.BandwidthConfig{
+			MaxTx: 123456,
+		},
+	})
+	assert.NoError(t, err)
+	assert.Equal(t, &client.HandshakeInfo{
+		UDPEnabled: true,
+		Tx:         0,
+	}, info)
+
+	// Close server 3 and client 3
+	_ = s.Close()
+	_ = c.Close()
+}

core/internal/integration_tests/stress_test.go

@@ -148,7 +148,7 @@ func TestClientServerTCPStress(t *testing.T) {
 	go echoServer.Serve()
 
 	// Create client
-	c, err := client.NewClient(&client.Config{
+	c, _, err := client.NewClient(&client.Config{
 		ServerAddr: udpAddr,
 		TLSConfig:  client.TLSConfig{InsecureSkipVerify: true},
 	})
@@ -192,7 +192,7 @@ func TestClientServerUDPStress(t *testing.T) {
 	go echoServer.Serve()
 
 	// Create client
-	c, err := client.NewClient(&client.Config{
+	c, _, err := client.NewClient(&client.Config{
 		ServerAddr: udpAddr,
 		TLSConfig:  client.TLSConfig{InsecureSkipVerify: true},
 	})

core/internal/integration_tests/trafficlogger_test.go

@@ -35,7 +35,7 @@ func TestClientServerTrafficLoggerTCP(t *testing.T) {
 	go s.Serve()
 
 	// Create client
-	c, err := client.NewClient(&client.Config{
+	c, _, err := client.NewClient(&client.Config{
 		ServerAddr: udpAddr,
 		TLSConfig:  client.TLSConfig{InsecureSkipVerify: true},
 	})
@@ -114,7 +114,7 @@ func TestClientServerTrafficLoggerUDP(t *testing.T) {
 	go s.Serve()
 
 	// Create client
-	c, err := client.NewClient(&client.Config{
+	c, _, err := client.NewClient(&client.Config{
 		ServerAddr: udpAddr,
 		TLSConfig:  client.TLSConfig{InsecureSkipVerify: true},
 	})