func JoinSession(invitation protocol.SessionInvitation) (net.Conn, error) {
addr := net.JoinHostPort(net.IP(invitation.Address).String(), strconv.Itoa(int(invitation.Port)))
conn, err := dialer.Dial("tcp", addr)
if err != nil {
return nil, err
}
request := protocol.JoinSessionRequest{
Key: invitation.Key,
}
conn.SetDeadline(time.Now().Add(10 * time.Second))
err = protocol.WriteMessage(conn, request)
if err != nil {
return nil, err
}
message, err := protocol.ReadMessage(conn)
if err != nil {
return nil, err
}
conn.SetDeadline(time.Time{})
switch msg := message.(type) {
case protocol.Response:
if msg.Code != 0 {
return nil, fmt.Errorf("Incorrect response code %d: %s", msg.Code, msg.Message)
}
return conn, nil
default:
return nil, fmt.Errorf("protocol error: expecting response got %v", msg)
}
}
func (c *staticClient) join() error {
if err := protocol.WriteMessage(c.conn, protocol.JoinRelayRequest{}); err != nil {
return err
}
message, err := protocol.ReadMessage(c.conn)
if err != nil {
return err
}
switch msg := message.(type) {
case protocol.Response:
if msg.Code != 0 {
return fmt.Errorf("Incorrect response code %d: %s", msg.Code, msg.Message)
}
case protocol.RelayFull:
return fmt.Errorf("relay full")
default:
return fmt.Errorf("protocol error: expecting response got %v", msg)
}
return nil
}
func GetInvitationFromRelay(uri *url.URL, id syncthingprotocol.DeviceID, certs []tls.Certificate, timeout time.Duration) (protocol.SessionInvitation, error) {
if uri.Scheme != "relay" {
return protocol.SessionInvitation{}, fmt.Errorf("Unsupported relay scheme: %v", uri.Scheme)
}
rconn, err := dialer.DialTimeout("tcp", uri.Host, timeout)
if err != nil {
return protocol.SessionInvitation{}, err
}
conn := tls.Client(rconn, configForCerts(certs))
conn.SetDeadline(time.Now().Add(timeout))
if err := performHandshakeAndValidation(conn, uri); err != nil {
return protocol.SessionInvitation{}, err
}
defer conn.Close()
request := protocol.ConnectRequest{
ID: id[:],
}
if err := protocol.WriteMessage(conn, request); err != nil {
return protocol.SessionInvitation{}, err
}
message, err := protocol.ReadMessage(conn)
if err != nil {
return protocol.SessionInvitation{}, err
}
switch msg := message.(type) {
case protocol.Response:
return protocol.SessionInvitation{}, fmt.Errorf("Incorrect response code %d: %s", msg.Code, msg.Message)
case protocol.SessionInvitation:
l.Debugln("Received invitation", msg, "via", conn.LocalAddr())
ip := net.IP(msg.Address)
if len(ip) == 0 || ip.IsUnspecified() {
msg.Address = conn.RemoteAddr().(*net.TCPAddr).IP[:]
}
return msg, nil
default:
return protocol.SessionInvitation{}, fmt.Errorf("protocol error: unexpected message %v", msg)
}
}
func (c *staticClient) Serve() {
c.stop = make(chan struct{})
c.stopped = make(chan struct{})
defer close(c.stopped)
if err := c.connect(); err != nil {
l.Debugln("Relay connect:", err)
return
}
l.Debugln(c, "connected", c.conn.RemoteAddr())
if err := c.join(); err != nil {
c.conn.Close()
l.Infoln("Relay join:", err)
return
}
if err := c.conn.SetDeadline(time.Time{}); err != nil {
c.conn.Close()
l.Infoln("Relay set deadline:", err)
return
}
l.Debugln(c, "joined", c.conn.RemoteAddr(), "via", c.conn.LocalAddr())
c.mut.Lock()
c.connected = true
c.mut.Unlock()
messages := make(chan interface{})
errors := make(chan error, 1)
go messageReader(c.conn, messages, errors)
timeout := time.NewTimer(c.messageTimeout)
for {
select {
case message := <-messages:
timeout.Reset(c.messageTimeout)
l.Debugf("%s received message %T", c, message)
switch msg := message.(type) {
case protocol.Ping:
if err := protocol.WriteMessage(c.conn, protocol.Pong{}); err != nil {
l.Infoln("Relay write:", err)
c.disconnect()
} else {
l.Debugln(c, "sent pong")
}
case protocol.SessionInvitation:
ip := net.IP(msg.Address)
if len(ip) == 0 || ip.IsUnspecified() {
msg.Address = c.conn.RemoteAddr().(*net.TCPAddr).IP[:]
}
c.invitations <- msg
case protocol.RelayFull:
l.Infoln("Disconnected from relay due to it becoming full.")
c.disconnect()
default:
l.Infoln("Relay: protocol error: unexpected message %v", msg)
c.disconnect()
}
case <-c.stop:
l.Debugln(c, "stopping")
c.disconnect()
// We always exit via this branch of the select, to make sure the
// the reader routine exits.
case err := <-errors:
close(errors)
close(messages)
c.mut.Lock()
if c.connected {
c.conn.Close()
c.connected = false
l.Infoln("Relay received:", err)
}
if c.closeInvitationsOnFinish {
close(c.invitations)
c.invitations = make(chan protocol.SessionInvitation)
}
c.mut.Unlock()
return
case <-timeout.C:
l.Debugln(c, "timed out")
c.disconnect()
}
}
}