Merge pull request #929 from lucas-clemente/fix-926

send initial version in the CHLO, not the current version

client.go

@@ -353,6 +353,7 @@ func (c *client) handleVersionNegotiationPacket(hdr *wire.Header) error {
 
 func (c *client) createNewSession(initialVersion protocol.VersionNumber, negotiatedVersions []protocol.VersionNumber) error {
 	var err error
+	utils.Debugf("createNewSession with initial version %s", initialVersion)
 	c.session, c.handshakeChan, err = newClientSession(
 		c.conn,
 		c.hostname,

internal/handshake/crypto_setup_client.go

@@ -23,6 +23,7 @@ type cryptoSetupClient struct {
 	hostname           string
 	connID             protocol.ConnectionID
 	version            protocol.VersionNumber
+	initialVersion     protocol.VersionNumber
 	negotiatedVersions []protocol.VersionNumber
 
 	cryptoStream io.ReadWriter
@@ -74,6 +75,7 @@ func NewCryptoSetupClient(
 	params *TransportParameters,
 	paramsChan chan<- TransportParameters,
 	aeadChanged chan<- protocol.EncryptionLevel,
+	initialVersion protocol.VersionNumber,
 	negotiatedVersions []protocol.VersionNumber,
 ) (CryptoSetup, error) {
 	nullAEAD, err := crypto.NewNullAEAD(protocol.PerspectiveClient, connID, version)
@@ -92,6 +94,7 @@ func NewCryptoSetupClient(
 		nullAEAD:           nullAEAD,
 		paramsChan:         paramsChan,
 		aeadChanged:        aeadChanged,
+		initialVersion:     initialVersion,
 		negotiatedVersions: negotiatedVersions,
 		divNonceChan:       make(chan []byte),
 	}, nil
@@ -423,7 +426,7 @@ func (h *cryptoSetupClient) getTags() (map[Tag][]byte, error) {
 	}
 
 	versionTag := make([]byte, 4)
-	binary.BigEndian.PutUint32(versionTag, uint32(h.version))
+	binary.BigEndian.PutUint32(versionTag, uint32(h.initialVersion))
 	tags[TagVER] = versionTag
 
 	if len(h.stk) > 0 {

internal/handshake/crypto_setup_client_test.go

@@ -105,7 +105,7 @@ var _ = Describe("Client Crypto Setup", func() {
 
 		stream = newMockStream()
 		certManager = &mockCertManager{}
-		version := protocol.Version37
+		version := protocol.Version39
 		// use a buffered channel here, so that we can parse a SHLO without having to receive the TransportParameters to avoid blocking
 		paramsChan = make(chan TransportParameters, 1)
 		aeadChanged = make(chan protocol.EncryptionLevel, 2)
@@ -118,6 +118,7 @@ var _ = Describe("Client Crypto Setup", func() {
 			&TransportParameters{IdleTimeout: protocol.DefaultIdleTimeout},
 			paramsChan,
 			aeadChanged,
+			protocol.Version37,
 			nil,
 		)
 		Expect(err).ToNot(HaveOccurred())
@@ -490,6 +491,7 @@ var _ = Describe("Client Crypto Setup", func() {
 		})
 
 		It("has the right values for an inchoate CHLO", func() {
+			Expect(cs.version).ToNot(Equal(cs.initialVersion)) // make sure we can test that TagVER actually has the initial version, and not the current version
 			cs.hostname = "sni-hostname"
 			certManager.commonCertificateHashes = []byte("common certs")
 			tags, err := cs.getTags()

session.go

@@ -148,7 +148,7 @@ var newClientSession = func(
 	connectionID protocol.ConnectionID,
 	tlsConf *tls.Config,
 	config *Config,
-	initialVersion protocol.VersionNumber, // needed for validation of the version negotaion over TLS
+	initialVersion protocol.VersionNumber,
 	negotiatedVersions []protocol.VersionNumber, // needed for validation of the GQUIC version negotiaton
 ) (packetHandler, <-chan handshakeEvent, error) {
 	s := &session{
@@ -158,7 +158,7 @@ var newClientSession = func(
 		version:      v,
 		config:       config,
 	}
-	return s.setup(nil, hostname, tlsConf, v, negotiatedVersions)
+	return s.setup(nil, hostname, tlsConf, initialVersion, negotiatedVersions)
 }
 
 func (s *session) setup(
@@ -261,6 +261,7 @@ func (s *session) setup(
 				transportParams,
 				paramsChan,
 				aeadChanged,
+				initialVersion,
 				negotiatedVersions,
 			)
 		}

session_test.go

@@ -1522,6 +1522,7 @@ var _ = Describe("Client Session", func() {
 			_ *handshake.TransportParameters,
 			_ chan<- handshake.TransportParameters,
 			aeadChangedP chan<- protocol.EncryptionLevel,
+			_ protocol.VersionNumber,
 			_ []protocol.VersionNumber,
 		) (handshake.CryptoSetup, error) {
 			aeadChanged = aeadChangedP