#!/bin/bash
function routeadd {
    route add -host xxx.xxx.xxx.xxx dev ppp0
    route add -net xxx.xxx.xxx.xxx/xx dev ppp0
}
function makepptp {
   echo pty "pptp xxx.xxx.xxx.xxx --nolaunchpppd" >> /etc/ppp/peers/vpn;
   echo remotename PPTP >> /etc/ppp/peers/vpn;
   echo require-mppe-128 >> /etc/ppp/peers/vpn;
   echo file /etc/ppp/options.pptp >> /etc/ppp/peers/vpn;
   echo ipparam vpn >> /etc/ppp/peers/vpn;
pppd call vpn &
}
if [ -a /etc/ppp/chap-secrets ];
        then
        rm /etc/ppp/chap-secrets
    echo $1 PPTP $2 '*' >> /etc/ppp/chap-secrets;
else
    echo $1 PPTP $2 '*' >> /etc/ppp/chap-secrets;
fi

if [ -e /etc/ppp/peers/vpn ];
    then
    rm /etc/ppp/peers/vpn;
    echo name $1 >> /etc/ppp/peers/vpn;
    makepptp;
    sleep 8;
    routeadd;
else
    echo name $1 >> /etc/ppp/peers/vpn;
    makepptp;
    sleep 8;
    routeadd;
fi

sudo /path_to_script/vpn username password

function routeadd {
        route add -host xxx.xxx.xxx.xxx dev ppp0
        route add -net xxx.xxx.xxx.xxx/xx dev ppp0
    }

function routeadd {
        route add -host ip_address_for_vnc dev eth0
        route add default dev ppp0
    }