only enable 0-RTT when using ListenEarly and DialEarly

client.go

@@ -249,7 +249,26 @@ func populateClientConfig(config *Config, createdPacketConn bool) *Config {
 
 func (c *client) dial(ctx context.Context) error {
 	c.logger.Infof("Starting new connection to %s (%s -> %s), source connection ID %s, destination connection ID %s, version %s", c.tlsConf.ServerName, c.conn.LocalAddr(), c.conn.RemoteAddr(), c.srcConnID, c.destConnID, c.version)
-	c.createNewTLSSession(c.version)
+
+	c.mutex.Lock()
+	c.session = newClientSession(
+		c.conn,
+		c.packetHandlers,
+		c.destConnID,
+		c.srcConnID,
+		c.config,
+		c.tlsConf,
+		c.initialPacketNumber,
+		c.initialVersion,
+		c.use0RTT,
+		c.logger,
+		c.version,
+	)
+	c.mutex.Unlock()
+	// It's not possible to use the stateless reset token for the client's (first) connection ID,
+	// since there's no way to securely communicate it to the server.
+	c.packetHandlers.Add(c.srcConnID, c)
+
 	err := c.establishSecureConnection(ctx)
 	if err == errCloseForRecreating {
 		return c.dial(ctx)
@@ -354,26 +373,6 @@ func (c *client) handleVersionNegotiationPacket(p *receivedPacket) {
 	c.initialPacketNumber = c.session.closeForRecreating()
 }
 
-func (c *client) createNewTLSSession(_ protocol.VersionNumber) {
-	c.mutex.Lock()
-	c.session = newClientSession(
-		c.conn,
-		c.packetHandlers,
-		c.destConnID,
-		c.srcConnID,
-		c.config,
-		c.tlsConf,
-		c.initialPacketNumber,
-		c.initialVersion,
-		c.logger,
-		c.version,
-	)
-	c.mutex.Unlock()
-	// It's not possible to use the stateless reset token for the client's (first) connection ID,
-	// since there's no way to securely communicate it to the server.
-	c.packetHandlers.Add(c.srcConnID, c)
-}
-
 func (c *client) Close() error {
 	c.mutex.Lock()
 	defer c.mutex.Unlock()

client_test.go

@@ -38,6 +38,7 @@ var _ = Describe("Client", func() {
 			tlsConf *tls.Config,
 			initialPacketNumber protocol.PacketNumber,
 			initialVersion protocol.VersionNumber,
+			enable0RTT bool,
 			logger utils.Logger,
 			v protocol.VersionNumber,
 		) quicSession
@@ -140,6 +141,7 @@ var _ = Describe("Client", func() {
 				_ *tls.Config,
 				_ protocol.PacketNumber,
 				_ protocol.VersionNumber,
+				_ bool,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {
@@ -170,6 +172,7 @@ var _ = Describe("Client", func() {
 				tlsConf *tls.Config,
 				_ protocol.PacketNumber,
 				_ protocol.VersionNumber,
+				_ bool,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {
@@ -200,6 +203,7 @@ var _ = Describe("Client", func() {
 				tlsConf *tls.Config,
 				_ protocol.PacketNumber,
 				_ protocol.VersionNumber,
+				_ bool,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {
@@ -235,9 +239,11 @@ var _ = Describe("Client", func() {
 				_ *tls.Config,
 				_ protocol.PacketNumber,
 				_ protocol.VersionNumber,
+				enable0RTT bool,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {
+				Expect(enable0RTT).To(BeFalse())
 				sess := NewMockQuicSession(mockCtrl)
 				sess.EXPECT().run().Do(func() { close(run) })
 				ctx, cancel := context.WithCancel(context.Background())
@@ -273,9 +279,11 @@ var _ = Describe("Client", func() {
 				_ *tls.Config,
 				_ protocol.PacketNumber,
 				_ protocol.VersionNumber,
+				enable0RTT bool,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {
+				Expect(enable0RTT).To(BeTrue())
 				sess := NewMockQuicSession(mockCtrl)
 				sess.EXPECT().run().Do(func() { <-done })
 				sess.EXPECT().HandshakeComplete().Return(context.Background())
@@ -316,6 +324,7 @@ var _ = Describe("Client", func() {
 				_ *tls.Config,
 				_ protocol.PacketNumber,
 				_ protocol.VersionNumber,
+				_ bool,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {
@@ -356,6 +365,7 @@ var _ = Describe("Client", func() {
 				_ *tls.Config,
 				_ protocol.PacketNumber,
 				_ protocol.VersionNumber,
+				_ bool,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {
@@ -404,6 +414,7 @@ var _ = Describe("Client", func() {
 				_ *tls.Config,
 				_ protocol.PacketNumber,
 				_ protocol.VersionNumber,
+				_ bool,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {
@@ -523,6 +534,7 @@ var _ = Describe("Client", func() {
 				_ *tls.Config,
 				_ protocol.PacketNumber,
 				_ protocol.VersionNumber, /* initial version */
+				_ bool,
 				_ utils.Logger,
 				versionP protocol.VersionNumber,
 			) quicSession {
@@ -571,6 +583,7 @@ var _ = Describe("Client", func() {
 					_ *tls.Config,
 					_ protocol.PacketNumber,
 					_ protocol.VersionNumber,
+					_ bool,
 					_ utils.Logger,
 					_ protocol.VersionNumber,
 				) quicSession {

integrationtests/self/zero_rtt_test.go

@@ -44,7 +44,7 @@ var _ = Describe("0-RTT", func() {
 				return proxy, &num0RTTPackets
 			}
 
-			dialAndReceiveSessionTicket := func(ln quic.Listener, proxyPort int) *tls.Config {
+			dialAndReceiveSessionTicket := func(ln quic.EarlyListener, proxyPort int) *tls.Config {
 				// dial the first session in order to receive a session ticket
 				go func() {
 					defer GinkgoRecover()
@@ -68,7 +68,7 @@ var _ = Describe("0-RTT", func() {
 				return clientConf
 			}
 
-			transfer0RTTData := func(ln quic.Listener, proxyPort int, clientConf *tls.Config, testdata []byte) {
+			transfer0RTTData := func(ln quic.EarlyListener, proxyPort int, clientConf *tls.Config, testdata []byte) {
 				// now dial the second session, and use 0-RTT to send some data
 				done := make(chan struct{})
 				go func() {
@@ -98,7 +98,7 @@ var _ = Describe("0-RTT", func() {
 			}
 
 			It("transfers 0-RTT data", func() {
-				ln, err := quic.ListenAddr(
+				ln, err := quic.ListenAddrEarly(
 					"localhost:0",
 					getTLSConfig(),
 					&quic.Config{
@@ -122,7 +122,7 @@ var _ = Describe("0-RTT", func() {
 
 			// Test that data intended to be sent with 1-RTT protection is not sent in 0-RTT packets.
 			It("waits until a session until the handshake is done", func() {
-				ln, err := quic.ListenAddr(
+				ln, err := quic.ListenAddrEarly(
 					"localhost:0",
 					getTLSConfig(),
 					&quic.Config{
@@ -199,7 +199,7 @@ var _ = Describe("0-RTT", func() {
 					num0RTTDropped uint32
 				)
 
-				ln, err := quic.ListenAddr(
+				ln, err := quic.ListenAddrEarly(
 					"localhost:0",
 					getTLSConfig(),
 					&quic.Config{
@@ -253,7 +253,7 @@ var _ = Describe("0-RTT", func() {
 				var firstConnID, secondConnID protocol.ConnectionID
 				var firstCounter, secondCounter int
 
-				ln, err := quic.ListenAddr(
+				ln, err := quic.ListenAddrEarly(
 					"localhost:0",
 					getTLSConfig(),
 					&quic.Config{Versions: []protocol.VersionNumber{version}},

server.go

@@ -72,7 +72,7 @@ type baseServer struct {
 	sessionHandler packetHandlerManager
 
 	// set as a member, so they can be set in the tests
-	newSession func(connection, sessionRunner, protocol.ConnectionID /* original connection ID */, protocol.ConnectionID /* client dest connection ID */, protocol.ConnectionID /* destination connection ID */, protocol.ConnectionID /* source connection ID */, [16]byte, *Config, *tls.Config, *handshake.TokenGenerator, utils.Logger, protocol.VersionNumber) quicSession
+	newSession func(connection, sessionRunner, protocol.ConnectionID /* original connection ID */, protocol.ConnectionID /* client dest connection ID */, protocol.ConnectionID /* destination connection ID */, protocol.ConnectionID /* source connection ID */, [16]byte, *Config, *tls.Config, *handshake.TokenGenerator, bool /* enable 0-RTT */, utils.Logger, protocol.VersionNumber) quicSession
 
 	serverError error
 	errorChan   chan struct{}
@@ -450,6 +450,7 @@ func (s *baseServer) createNewSession(
 		s.config,
 		s.tlsConf,
 		s.tokenGenerator,
+		s.acceptEarlySessions,
 		s.logger,
 		version,
 	)

server_test.go

@@ -331,9 +331,11 @@ var _ = Describe("Server", func() {
 					_ *Config,
 					_ *tls.Config,
 					_ *handshake.TokenGenerator,
+					enable0RTT bool,
 					_ utils.Logger,
 					_ protocol.VersionNumber,
 				) quicSession {
+					Expect(enable0RTT).To(BeFalse())
 					Expect(origConnID).To(Equal(hdr.DestConnectionID))
 					Expect(destConnID).To(Equal(hdr.SrcConnectionID))
 					// make sure we're using a server-generated connection ID
@@ -381,6 +383,7 @@ var _ = Describe("Server", func() {
 					_ *Config,
 					_ *tls.Config,
 					_ *handshake.TokenGenerator,
+					_ bool,
 					_ utils.Logger,
 					_ protocol.VersionNumber,
 				) quicSession {
@@ -409,6 +412,7 @@ var _ = Describe("Server", func() {
 					_ *Config,
 					_ *tls.Config,
 					_ *handshake.TokenGenerator,
+					_ bool,
 					_ utils.Logger,
 					_ protocol.VersionNumber,
 				) quicSession {
@@ -469,6 +473,7 @@ var _ = Describe("Server", func() {
 					_ *Config,
 					_ *tls.Config,
 					_ *handshake.TokenGenerator,
+					_ bool,
 					_ utils.Logger,
 					_ protocol.VersionNumber,
 				) quicSession {
@@ -572,6 +577,7 @@ var _ = Describe("Server", func() {
 					_ *Config,
 					_ *tls.Config,
 					_ *handshake.TokenGenerator,
+					_ bool,
 					_ utils.Logger,
 					_ protocol.VersionNumber,
 				) quicSession {
@@ -624,9 +630,11 @@ var _ = Describe("Server", func() {
 				_ *Config,
 				_ *tls.Config,
 				_ *handshake.TokenGenerator,
+				enable0RTT bool,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {
+				Expect(enable0RTT).To(BeTrue())
 				sess.EXPECT().run().Do(func() {})
 				sess.EXPECT().earlySessionReady().Return(ready)
 				sess.EXPECT().Context().Return(context.Background())
@@ -653,6 +661,7 @@ var _ = Describe("Server", func() {
 				_ *Config,
 				_ *tls.Config,
 				_ *handshake.TokenGenerator,
+				_ bool,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {
@@ -709,6 +718,7 @@ var _ = Describe("Server", func() {
 				_ *Config,
 				_ *tls.Config,
 				_ *handshake.TokenGenerator,
+				_ bool,
 				_ utils.Logger,
 				_ protocol.VersionNumber,
 			) quicSession {

session.go

@@ -202,6 +202,7 @@ var newSession = func(
 	conf *Config,
 	tlsConf *tls.Config,
 	tokenGenerator *handshake.TokenGenerator,
+	enable0RTT bool,
 	logger utils.Logger,
 	v protocol.VersionNumber,
 ) quicSession {
@@ -274,7 +275,7 @@ var newSession = func(
 			},
 		},
 		tlsConf,
-		true, // TODO: make 0-RTT support configurable
+		enable0RTT,
 		s.rttStats,
 		logger,
 	)
@@ -308,6 +309,7 @@ var newClientSession = func(
 	tlsConf *tls.Config,
 	initialPacketNumber protocol.PacketNumber,
 	initialVersion protocol.VersionNumber,
+	enable0RTT bool,
 	logger utils.Logger,
 	v protocol.VersionNumber,
 ) quicSession {
@@ -371,7 +373,7 @@ var newClientSession = func(
 			onHandshakeComplete: func() { close(s.handshakeCompleteChan) },
 		},
 		tlsConf,
-		true, // TODO: make 0-RTT support configurable
+		enable0RTT,
 		s.rttStats,
 		logger,
 	)

session_test.go

@@ -122,6 +122,7 @@ var _ = Describe("Session", func() {
 			populateServerConfig(&Config{}),
 			nil, // tls.Config
 			tokenGenerator,
+			false,
 			utils.DefaultLogger,
 			protocol.VersionTLS,
 		).(*session)
@@ -1658,6 +1659,7 @@ var _ = Describe("Client Session", func() {
 			tlsConf,
 			42, // initial packet number
 			protocol.VersionTLS,
+			false,
 			utils.DefaultLogger,
 			protocol.VersionTLS,
 		).(*session)