NatOption
static int NatOption(struct cmdargs const *);
{"deny_incoming", NULL, NatOption, LOCAL_AUTH,
{"log", NULL, NatOption, LOCAL_AUTH,
{"same_ports", NULL, NatOption, LOCAL_AUTH,
{"unregistered_only", NULL, NatOption, LOCAL_AUTH,
{"use_sockets", NULL, NatOption, LOCAL_AUTH,
{"udp_eim", NULL, NatOption, LOCAL_AUTH,