#!/bin/sh

# Based on
# https://www.snbforums.com/threads/a-guide-about-installing-zerotier-on-asus-ac68u-router.42648/

start() {
    if ( pidof zerotier-one )
    then echo "ZeroTier-One is already running."
    else
        echo "Starting ZeroTier-One" ;
        
        # start TUN, or else will get `ERROR: unable to configure virtual network port: could not open TUN/TAP device: No such file or directory`
        modprobe tun

        /opt/bin/zerotier-one -d;
        
        echo 1 > /proc/sys/net/ipv4/ip_forward

        # QNAP
        iptables -t nat -A POSTROUTING -o eth1 -j MASQUERADE
        iptables -A FORWARD -i eth1 -o ztmjfmodu -m state --state RELATED,ESTABLISHED -j ACCEPT
        iptables -A FORWARD -i ztmjfmodu -o eth1 -j ACCEPT

        echo "$(date) Started ZeroTier-One" >> /opt/var/log/zerotier-one.log ;
    fi
}

stop() {
    if ( pidof zerotier-one )
    then
        echo "Stopping ZeroTier-One";
        killall zerotier-one
        echo "$(date) Stopped ZeroTier-One" >> /opt/var/log/zerotier-one.log
    else
        echo "ZeroTier-One was not running" ;
    fi
}

case "$1" in
    start)
        start
        ;;
    stop)
        stop
        ;;
    restart)
        stop
        start
        ;;
    status)
        if ( pidof zerotier-one )
        then echo "ZeroTier-One is running."
        else echo "ZeroTier-One is NOT running"
        fi
        ;;
    *)
        echo "Usage: $0 {start|stop|restart|status}"
        exit 1
        ;;
esac

exit 0