IPV6_FW_IP6OPT_ESP
if (chain->fw_ip6opt & IPV6_FW_IP6OPT_ESP) PRINTOPT("esp");
if (chain->fw_ip6nopt & IPV6_FW_IP6OPT_ESP) PRINTOPT("!esp");
if (!strncmp(p,"esp",strlen(p))) *d |= IPV6_FW_IP6OPT_ESP;
opts &= ~IPV6_FW_IP6OPT_ESP;
nopts &= ~IPV6_FW_IP6OPT_ESP;