#!/bin/bash

function usage() {
    echo "Usage":
    echo $0 "[open|close]"
}

cmd=$1

if [ "$cmd" != "open" ] && [ "$cmd" != "close" ];then
    usage
    exit
fi

if [ "$cmd" == "close" ];then
    ip6tables-save  | grep "dport 25" | grep REJECT || ip6tables -A OUTPUT -p tcp --dport 25 -j REJECT
fi

if [ "$cmd" == "open" ];then
    ip6tables-save  | grep "dport 25" | grep REJECT | sed 's/^-A/ip6tables -D/' | bash
fi
