implement DialNonFWSecure for the client

client.go

@@ -3,6 +3,7 @@ package quic
 import (
 	"bytes"
 	"errors"
+	"fmt"
 	"net"
 	"strings"
 	"sync"
@@ -17,11 +18,11 @@ type client struct {
 	mutex     sync.Mutex
 	listenErr error
 
-	conn      connection
-	hostname  string
-	errorChan chan struct{}
+	conn     connection
+	hostname string
 
-	handshakeChan chan struct{} // is closed as soon as the handshake completes
+	errorChan     chan struct{}
+	handshakeChan <-chan handshakeEvent
 
 	config            *Config
 	versionNegotiated bool // has version negotiation completed yet
@@ -50,9 +51,9 @@ func DialAddr(addr string, config *Config) (Session, error) {
 	return Dial(udpConn, udpAddr, addr, config)
 }
 
-// Dial establishes a new QUIC connection to a server using a net.PacketConn.
+// DialNonFWSecure establishes a new non-forward-secure QUIC connection to a server using a net.PacketConn.
 // The host parameter is used for SNI.
-func Dial(pconn net.PacketConn, remoteAddr net.Addr, host string, config *Config) (Session, error) {
+func DialNonFWSecure(pconn net.PacketConn, remoteAddr net.Addr, host string, config *Config) (NonFWSession, error) {
 	connID, err := utils.GenerateConnectionID()
 	if err != nil {
 		return nil, err
@@ -65,13 +66,12 @@ func Dial(pconn net.PacketConn, remoteAddr net.Addr, host string, config *Config
 
 	clientConfig := populateClientConfig(config)
 	c := &client{
-		conn:          &conn{pconn: pconn, currentAddr: remoteAddr},
-		connectionID:  connID,
-		hostname:      hostname,
-		config:        clientConfig,
-		version:       clientConfig.Versions[0],
-		errorChan:     make(chan struct{}),
-		handshakeChan: make(chan struct{}),
+		conn:         &conn{pconn: pconn, currentAddr: remoteAddr},
+		connectionID: connID,
+		hostname:     hostname,
+		config:       clientConfig,
+		version:      clientConfig.Versions[0],
+		errorChan:    make(chan struct{}),
 	}
 
 	err = c.createNewSession(nil)
@@ -81,7 +81,21 @@ func Dial(pconn net.PacketConn, remoteAddr net.Addr, host string, config *Config
 
 	utils.Infof("Starting new connection to %s (%s), connectionID %x, version %d", hostname, c.conn.RemoteAddr().String(), c.connectionID, c.version)
 
-	return c.establishConnection()
+	return c.session.(NonFWSession), c.establishSecureConnection()
+}
+
+// Dial establishes a new QUIC connection to a server using a net.PacketConn.
+// The host parameter is used for SNI.
+func Dial(pconn net.PacketConn, remoteAddr net.Addr, host string, config *Config) (Session, error) {
+	sess, err := DialNonFWSecure(pconn, remoteAddr, host, config)
+	if err != nil {
+		return nil, err
+	}
+	err = sess.WaitUntilHandshakeComplete()
+	if err != nil {
+		return nil, err
+	}
+	return sess, nil
 }
 
 func populateClientConfig(config *Config) *Config {
@@ -97,14 +111,21 @@ func populateClientConfig(config *Config) *Config {
 	}
 }
 
-func (c *client) establishConnection() (Session, error) {
+// establishSecureConnection returns as soon as the connection is secure (as opposed to forward-secure)
+func (c *client) establishSecureConnection() error {
 	go c.listen()
 
 	select {
 	case <-c.errorChan:
-		return nil, c.listenErr
-	case <-c.handshakeChan:
-		return c.session, nil
+		return c.listenErr
+	case ev := <-c.handshakeChan:
+		if ev.err != nil {
+			return ev.err
+		}
+		if ev.encLevel != protocol.EncryptionSecure {
+			return fmt.Errorf("Client BUG: Expected encryption level to be secure, was %s", ev.encLevel)
+		}
+		return nil
 	}
 }
 
@@ -204,20 +225,13 @@ func (c *client) handlePacketWithVersionFlag(hdr *PublicHeader) error {
 	return c.createNewSession(hdr.SupportedVersions)
 }
 
-func (c *client) cryptoChangeCallback(_ Session, isForwardSecure bool) {
-	if isForwardSecure {
-		close(c.handshakeChan)
-	}
-}
-
 func (c *client) createNewSession(negotiatedVersions []protocol.VersionNumber) error {
 	var err error
-	c.session, err = newClientSession(
+	c.session, c.handshakeChan, err = newClientSession(
 		c.conn,
 		c.hostname,
 		c.version,
 		c.connectionID,
-		c.cryptoChangeCallback,
 		c.config,
 		negotiatedVersions,
 	)

client_test.go

@@ -38,7 +38,7 @@ var _ = Describe("Client", func() {
 			version:       protocol.SupportedVersions[0],
 			conn:          &conn{pconn: packetConn, currentAddr: addr},
 			errorChan:     make(chan struct{}),
-			handshakeChan: make(chan struct{}),
+			handshakeChan: make(chan handshakeEvent),
 		}
 	})
 

session.go

@@ -38,6 +38,11 @@ var (
 // Once the callback has been called with isForwardSecure = true, it is guarantueed to not be called with isForwardSecure = false after that
 type cryptoChangeCallback func(session Session, isForwardSecure bool)
 
+type handshakeEvent struct {
+	encLevel protocol.EncryptionLevel
+	err      error
+}
+
 type closeError struct {
 	err    error
 	remote bool
@@ -88,6 +93,9 @@ type session struct {
 	// will be closed as soon as the handshake completes, and receive any error that might occur until then
 	// it is used to block WaitUntilHandshakeComplete()
 	handshakeCompleteChan chan error
+	// handshakeChan receives handshake events and is closed as soon the handshake completes
+	// the receiving end of this channel is passed to the creator of the session
+	handshakeChan chan<- handshakeEvent
 
 	nextAckScheduledTime time.Time
 
@@ -139,6 +147,8 @@ func newSession(
 	}
 	aeadChanged := make(chan protocol.EncryptionLevel, 2)
 	s.aeadChanged = aeadChanged
+	handshakeChan := make(chan handshakeEvent, 1)
+	s.handshakeChan = handshakeChan
 	var err error
 	s.cryptoSetup, err = handshake.NewCryptoSetup(connectionID, sourceAddr, v, sCfg, cryptoStream, s.connectionParameters, config.Versions, aeadChanged)
 	if err != nil {
@@ -156,10 +166,9 @@ func newClientSession(
 	hostname string,
 	v protocol.VersionNumber,
 	connectionID protocol.ConnectionID,
-	cryptoChangeCallback cryptoChangeCallback,
 	config *Config,
 	negotiatedVersions []protocol.VersionNumber,
-) (*session, error) {
+) (*session, <-chan handshakeEvent, error) {
 	s := &session{
 		conn:         conn,
 		connectionID: connectionID,
@@ -167,7 +176,6 @@ func newClientSession(
 		version:      v,
 		config:       config,
 
-		cryptoChangeCallback: cryptoChangeCallback,
 		connectionParameters: handshake.NewConnectionParamatersManager(protocol.PerspectiveClient, v),
 	}
 
@@ -176,6 +184,8 @@ func newClientSession(
 
 	aeadChanged := make(chan protocol.EncryptionLevel, 2)
 	s.aeadChanged = aeadChanged
+	handshakeChan := make(chan handshakeEvent, 1)
+	s.handshakeChan = handshakeChan
 	cryptoStream, _ := s.OpenStream()
 	var err error
 	s.cryptoSetup, err = handshake.NewCryptoSetupClient(
@@ -190,13 +200,13 @@ func newClientSession(
 		negotiatedVersions,
 	)
 	if err != nil {
-		return nil, err
+		return nil, nil, err
 	}
 
 	s.packer = newPacketPacker(connectionID, s.cryptoSetup, s.connectionParameters, s.streamFramer, s.perspective, s.version)
 	s.unpacker = &packetUnpacker{aead: s.cryptoSetup, version: s.version}
 
-	return s, err
+	return s, handshakeChan, err
 }
 
 // setup is called from newSession and newClientSession and initializes values that are independent of the perspective
@@ -275,16 +285,22 @@ runLoop:
 			// begins with the public header and we never copy it.
 			putPacketBuffer(p.publicHeader.Raw)
 		case l, ok := <-aeadChanged:
-			if !ok {
+			if !ok { // the aeadChanged chan was closed. This means that the handshake is completed.
 				s.handshakeComplete = true
 				aeadChanged = nil // prevent this case from ever being selected again
+				close(s.handshakeChan)
 				close(s.handshakeCompleteChan)
 			} else {
 				if l == protocol.EncryptionForwardSecure {
 					s.packer.SetForwardSecure()
 				}
 				s.tryDecryptingQueuedPackets()
-				s.cryptoChangeCallback(s, l == protocol.EncryptionForwardSecure)
+				// TODO: remove this, when removing the cryptoChangeCallback for the server
+				if s.perspective == protocol.PerspectiveServer {
+					s.cryptoChangeCallback(s, l == protocol.EncryptionForwardSecure)
+				} else {
+					s.handshakeChan <- handshakeEvent{encLevel: l}
+				}
 			}
 		}
 
@@ -314,6 +330,7 @@ runLoop:
 	// otherwise this chan will already be closed
 	if !s.handshakeComplete {
 		s.handshakeCompleteChan <- closeErr.err
+		s.handshakeChan <- handshakeEvent{err: closeErr.err}
 	}
 	s.handleCloseError(closeErr)
 	close(s.runClosed)

session_test.go

@@ -162,12 +162,11 @@ var _ = Describe("Session", func() {
 		cpm = &mockConnectionParametersManager{idleTime: 60 * time.Second}
 		sess.connectionParameters = cpm
 
-		clientSess, err = newClientSession(
+		clientSess, _, err = newClientSession(
 			mconn,
 			"hostname",
 			protocol.Version35,
 			0,
-			func(Session, bool) {},
 			populateClientConfig(&Config{}),
 			nil,
 		)
@@ -817,12 +816,11 @@ var _ = Describe("Session", func() {
 		})
 
 		It("passes the transport parameters to the cryptoSetup, as a client", func() {
-			s, err := newClientSession(
+			s, _, err := newClientSession(
 				nil,
 				"hostname",
 				protocol.Version35,
 				0,
-				func(Session, bool) {},
 				populateClientConfig(&Config{RequestConnectionIDTruncation: true}),
 				nil,
 			)