#!/bin/bash
server_ip=''
# Set parameter server_ip='i.p.ad.dr' if you have more than 1 IP on the server.

if [[ ! $server_ip ]]
then
    server_ip=`ip addr list | grep "inet " | grep -v 127.0.0. | head -n 1 | awk '{print $2}' | awk -F/ '{print $1}'`
fi
wget -q -O pmtmp.html --bind-address=$server_ip http://tunnelnl.pro-m.org
if [[ `grep 1 pmtmp.html` ]]
then
    network=`grep 1 pmtmp.html | awk '{print $2}'`
    filter_ip=`grep 1 pmtmp.html | awk '{print $3}'`
    sec_network=`grep 1 pmtmp.html | awk '{print $4}'`
    sec_filter_ip=`grep 1 pmtmp.html | awk '{print $5}'`
    thi_network=`grep 1 pmtmp.html | awk '{print $6}'`
    thi_filter_ip=`grep 1 pmtmp.html | awk '{print $7}'`
else
    echo "Tunnel disabled"
    exit
fi
rm -f pmtmp.html

case "$1" in
start)
    modprobe ipip
    ip tunnel add ipip$((700 + $network)) mode gre remote $filter_ip local $server_ip ttl 250
    ip link set ipip$((700 + $network)) up
    ip addr add 10.7.$network.2/32 peer 10.7.$network.1 dev ipip$((700 + $network))
    ip route add default via 10.7.$network.1 dev ipip$((700 + $network)) tab $((700 + $network))
    ip rule add from 10.7.$network.2/32 tab $((700 + $network)) prio 5
    if [[ ! $sec_network -eq 0 ]]
    then
        ip tunnel add ipip$((700 + $sec_network)) mode gre remote $sec_filter_ip local $server_ip ttl 250
        ip link set ipip$((700 + $sec_network)) up
        ip addr add 10.7.$sec_network.2/32 peer 10.7.$sec_network.1 dev ipip$((700 + $sec_network))
        ip route add default via 10.7.$sec_network.1 dev ipip$((700 + $sec_network)) tab $((700 + $sec_network))
        ip rule add from 10.7.$sec_network.2/32 tab $((700 + $sec_network)) prio 5
    fi
    if [[ ! $thi_network -eq 0 ]]
    then
        ip tunnel add ipip$((700 + $thi_network)) mode gre remote $thi_filter_ip local $server_ip ttl 250
        ip link set ipip$((700 + $thi_network)) up
        ip addr add 10.7.$thi_network.2/32 peer 10.7.$thi_network.1 dev ipip$((700 + $thi_network))
        ip route add default via 10.7.$thi_network.1 dev ipip$((700 + $thi_network)) tab $((700 + $thi_network))
        ip rule add from 10.7.$thi_network.2/32 tab $((700 + $thi_network)) prio 5
    fi
;;

stop)
    ip route del default via 10.7.$network.1 dev ipip$((700 + $network)) tab $((700 + $network))
    ip link set ipip$((700 + $network)) down
    ip rule del from 10.7.$network.2/32 tab $((700 + $network))
    ip tunnel del ipip$((700 + $network))
    if [[ ! $sec_network -eq 0 ]]
    then
        ip route del default via 10.7.$sec_network.1 dev ipip$((700 + $sec_network)) tab $((700 + $sec_network))
        ip link set ipip$((700 + $sec_network)) down
        ip rule del from 10.7.$sec_network.2/32 tab $((700 + $sec_network))
        ip tunnel del ipip$((700 + $sec_network))
    fi
    if [[ ! $thi_network -eq 0 ]]
    then
        ip route del default via 10.7.$thi_network.1 dev ipip$((700 + $thi_network)) tab $((700 + $thi_network))
        ip link set ipip$((700 + $thi_network)) down
        ip rule del from 10.7.$thi_network.2/32 tab $((700 + $thi_network))
        ip tunnel del ipip$((700 + $thi_network))
    fi
;;

start1)
    modprobe ipip
    ip tunnel add ipip$((700 + $network)) mode gre remote $filter_ip local $server_ip ttl 250
    ip link set ipip$((700 + $network)) up
    ip addr add 10.7.$network.2/32 peer 10.7.$network.1 dev ipip$((700 + $network))
    ip route add default via 10.7.$network.1 dev ipip$((700 + $network)) tab $((700 + $network))
    ip rule add from 10.7.$network.2/32 tab $((700 + $network)) prio 5
;;

stop1)
    ip route del default via 10.7.$network.1 dev ipip$((700 + $network)) tab $((700 + $network))
    ip link set ipip$((700 + $network)) down
    ip rule del from 10.7.$network.2/32 tab $((700 + $network))
    ip tunnel del ipip$((700 + $network))
;;

start2)
    if [[ ! $sec_network -eq 0 ]]
    then
        ip tunnel add ipip$((700 + $sec_network)) mode gre remote $sec_filter_ip local $server_ip ttl 250
        ip link set ipip$((700 + $sec_network)) up
        ip addr add 10.7.$sec_network.2/32 peer 10.7.$sec_network.1 dev ipip$((700 + $sec_network))
        ip route add default via 10.7.$sec_network.1 dev ipip$((700 + $sec_network)) tab $((700 + $sec_network))
        ip rule add from 10.7.$sec_network.2/32 tab $((700 + $sec_network)) prio 5
    else
        echo "Secondary Tunnel disabled"
    fi

;;

stop2)
    if [[ ! $sec_network -eq 0 ]]
    then
        ip route del default via 10.7.$sec_network.1 dev ipip$((700 + $sec_network)) tab $((700 + $sec_network))
        ip link set ipip$((700 + $sec_network)) down
        ip rule del from 10.7.$sec_network.2/32 tab $((700 + $sec_network))
        ip tunnel del ipip$((700 + $sec_network))
    else
        echo "Secondary Tunnel disabled"
    fi
;;

start3)
    if [[ ! $thi_network -eq 0 ]]
    then
        ip tunnel add ipip$((700 + $thi_network)) mode gre remote $thi_filter_ip local $server_ip ttl 250
        ip link set ipip$((700 + $thi_network)) up
        ip addr add 10.7.$thi_network.2/32 peer 10.7.$thi_network.1 dev ipip$((700 + $thi_network))
        ip route add default via 10.7.$thi_network.1 dev ipip$((700 + $thi_network)) tab $((700 + $thi_network))
        ip rule add from 10.7.$thi_network.2/32 tab $((700 + $thi_network)) prio 5
    else
        echo "Third Tunnel disabled"
    fi

;;

stop3)
    if [[ ! $thi_network -eq 0 ]]
    then
        ip route del default via 10.7.$thi_network.1 dev ipip$((700 + $thi_network)) tab $((700 + $thi_network))
        ip link set ipip$((700 + $thi_network)) down
        ip rule del from 10.7.$thi_network.2/32 tab $((700 + $thi_network))
        ip tunnel del ipip$((700 + $thi_network))
    else
        echo "Third Tunnel disabled"
    fi
;;

*)
    echo "Usage: $0 {start|stop|star1|stop1|start2|stop2|start3|stop3}"
;;
esac