upnp

type NAT interface {
	// Get the external address from outside the NAT.
	GetExternalAddress() (addr net.IP, err error)
	// Add a port mapping for protocol (
	// "udp" or "tcp") from external port to internal port with description
	// lasting for timeout.
	AddPortMapping(protocol string, externalPort, internalPort int,
		description string, timeout int) (mappedExternalPort int, err error)
	// Remove a previously added port mapping from external port to internal
	// port.
	DeletePortMapping(protocol string, externalPort,
		internalPort int) (err error)
}