//Start vnc server now it's xpra and connect to server
func (c *vncRemoton) Start(session *remoton.SessionClient, password string) error {
var err error
var port string
port, c.iport = common.FindFreePortTCP(6900)
addrSrv := net.JoinHostPort("localhost", port)
c.xpra.SetPassword(password)
err = c.xpra.Bind(addrSrv)
if err != nil {
log.Error("vncRemoton:", err)
return err
}
conn, err := net.DialTimeout("tcp", addrSrv, time.Second*3)
if err != nil {
c.xpra.Terminate()
return err
}
conn.Close()
log.Println("started xpra")
go c.startNat(addrSrv)
go c.startRPC(
common.Capabilities{
XpraVersion: c.xpra.Version(),
},
session,
addrSrv)
go c.start(session, addrSrv)
return nil
}
//startNat add support for nat
func (c *vncRemoton) startNat(addrSrv string) error {
var err error
var eport string
eport, c.eport = common.FindFreePortTCP(44442)
c.natif, err = nat.Parse("any")
if err != nil {
log.Error(err)
return err
}
if _, err = c.natif.ExternalIP(); err != nil {
return err
}
if err = c.natif.DeleteMapping("TCP", 9932, c.eport); err != nil {
log.Infof("can't delete external map: %s", err.Error())
}
if err = c.natif.AddMapping("TCP", 9932, c.eport, "remoton", time.Hour); err != nil {
log.Infof("can't add mapping external map: %d -> %d", 9932, c.eport)
return err
}
c.elistener, err = net.Listen("tcp", net.JoinHostPort("0.0.0.0", eport))
if err != nil {
return err
}
log.Println("Nat enabled")
//redict from public to localhost
go func() {
eip, err := c.natif.ExternalIP()
if err != nil {
return
}
for {
conn, err := c.elistener.Accept()
if err != nil {
break
}
//only allow frow gateway
if !strings.EqualFold(conn.RemoteAddr().String(), eip.String()) {
conn.Close()
continue
}
proxy, err := net.DialTimeout("tcp", addrSrv, time.Second)
if err != nil {
break
}
go io.Copy(conn, proxy)
go io.Copy(proxy, conn)
}
}()
return nil
}
func (c *tunnelRemoton) srvTunnel(session *remoton.SessionClient) error {
port, _ := common.FindFreePortTCP(55123)
addrSrv := "localhost:" + port
log.Println("listen at " + addrSrv)
listener, err := net.Listen("tcp", addrSrv)
if err != nil {
return err
}
c.listener = listener
go func(listener net.Listener) {
for {
conn, err := listener.Accept()
if err != nil {
listener.Close()
log.Error(err)
break
}
remote, err := session.DialTCP("nx")
if err != nil {
log.Error(err)
listener.Close()
break
}
log.Println("new connection")
go c.handle(conn, remote)
}
}(listener)
log.Println("Xpra " + c.xpraSrv.Version() + " attaching to " + addrSrv)
err = c.xpraSrv.Attach(addrSrv)
if err != nil {
listener.Close()
return err
}
return nil
}