#!/bin/sh
#------------------------------------------------
# IPIP tunnel config scipt on proxy side
#
# By Yu Cai (ycai@uccs.edu) at UCCS, June 2003
#------------------------------------------------

iptables -F
iptables -P INPUT ACCEPT
iptables -P FORWARD ACCEPT
#enable ip forwarding
echo "1" > /proc/sys/net/ipv4/ip_forward

#define var
client_ip=128.198.61.51
client_gw=128.198.61.1
proxy_ip=128.198.60.42
proxy_gw=128.198.60.1
gw_ip=128.198.60.200
gw_gw=128.198.60.129
target_ip=128.198.60.201

#config tunnel between proxy and client
tunl=tunl1
ip tunnel add $tunl mode ipip remote $client_ip dev eth0 
ifconfig $tunl $proxy_ip
ip link set $tunl up
ip route add $client_ip via $proxy_gw dev $tunl onlink

#config tunnel between proxy and gateway
tunl=tunl2
ip tunnel add $tunl mode ipip remote $gw_ip dev eth0 
ifconfig $tunl $proxy_ip
ip link set $tunl up
ip route add $gw_ip via $proxy_gw dev $tunl onlink

#route between proxy and target through tunnel
ip route add $target_ip via $proxy_gw dev $tunl onlink