func (c *staticClient) connect() error {
if c.uri.Scheme != "relay" {
return fmt.Errorf("Unsupported relay schema: %v", c.uri.Scheme)
}
t0 := time.Now()
tcpConn, err := dialer.DialTimeout("tcp", c.uri.Host, c.connectTimeout)
if err != nil {
return err
}
c.mut.Lock()
c.latency = time.Since(t0)
c.mut.Unlock()
conn := tls.Client(tcpConn, c.config)
if err := conn.SetDeadline(time.Now().Add(c.connectTimeout)); err != nil {
conn.Close()
return err
}
if err := performHandshakeAndValidation(conn, c.uri); err != nil {
conn.Close()
return err
}
c.conn = conn
return nil
}
// TCPPing returns the duration required to establish a TCP connection
// to the given host. ICMP packets require root priviledges, hence why we use
// tcp.
func TCPPing(address string) (time.Duration, error) {
start := time.Now()
conn, err := dialer.DialTimeout("tcp", address, time.Second)
if conn != nil {
conn.Close()
}
return time.Since(start), err
}
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)
}
}