maemo.org - Talk - [Solved] Sip over Openvpn on 3g and wifi

Hi,

I have finally a working sip over openvpn today and wanted to post about it for everybodys benefit. I have tested this both on 3g (using three UK) and wifi. Here are the following files needed. All these files go in /etc/openvpn.

First the client config

Code:

#cat  openvpn_client.conf

client

script-security 2

up /etc/openvpn/nokia.up

down /etc/openvpn/nokia.down

ipchange /etc/openvpn/add_default_route.sh

dev tun

proto udp

remote xx.dyndns.org 1194

resolv-retry infinite

nobind

persist-key

persist-tun

ca ca.crt

cert client.crt

key client.key

comp-lzo

verb 3

nokia.up script

Code:

 

# cat nokia.up 

#!/bin/bash



case $script_type in



up)

    for optionname in ${!foreign_option_*} ; do

        option="${!optionname}"

        echo $option

        part1=$(echo "$option" | cut -d " " -f 1)

        if [ "$part1" == "dhcp-option" ] ; then

            part2=$(echo "$option" | cut -d " " -f 2)

            part3=$(echo "$option" | cut -d " " -f 3)

            if [ "$part2" == "DNS" ] ; then

                IF_DNS_NAMESERVERS="$IF_DNS_NAMESERVERS $part3"

            fi

            if [ "$part2" == "DOMAIN" ] ; then

                IF_DNS_SEARCH="$part3"

            fi

        fi

    done

    R=""

    if [ "$IF_DNS_SEARCH" ] ; then

        R="${R}search $IF_DNS_SEARCH\n"

    fi

    for NS in $IF_DNS_NAMESERVERS ; do

        R="${R}nameserver $NS\n"

    done

    if [ ! -f /etc/resolv.conf.prevpn ] ; then

        mv /etc/resolv.conf /etc/resolv.conf.prevpn

    fi

    echo -e "$R" > /etc/resolv.conf

    ;;



down)

    if [ -f /etc/resolv.conf.prevpn ] ; then

        mv /etc/resolv.conf.prevpn /etc/resolv.conf

    fi

    ;;



esac





source /etc/osso-af-init/af-defines.sh



for acct in `mc-tool list | grep sofiasip/sip`; do 

        mc-tool update $acct string:local-ip-address=$4



done

nokia.down script

Code:



#cat nokia.down



#!/bin/bash



case $script_type in



up)

    for optionname in ${!foreign_option_*} ; do

        option="${!optionname}"

        echo $option

        part1=$(echo "$option" | cut -d " " -f 1)

        if [ "$part1" == "dhcp-option" ] ; then

            part2=$(echo "$option" | cut -d " " -f 2)

            part3=$(echo "$option" | cut -d " " -f 3)

            if [ "$part2" == "DNS" ] ; then

                IF_DNS_NAMESERVERS="$IF_DNS_NAMESERVERS $part3"

            fi

            if [ "$part2" == "DOMAIN" ] ; then

                IF_DNS_SEARCH="$part3"

            fi

        fi

    done

    R=""

    if [ "$IF_DNS_SEARCH" ] ; then

        R="${R}search $IF_DNS_SEARCH\n"

    fi

    for NS in $IF_DNS_NAMESERVERS ; do

        R="${R}nameserver $NS\n"

    done

    if [ ! -f /etc/resolv.conf.prevpn ] ; then

        mv /etc/resolv.conf /etc/resolv.conf.prevpn

    fi

    echo -e "$R" > /etc/resolv.conf

    ;;



down)

    if [ -f /etc/resolv.conf.prevpn ] ; then

        mv /etc/resolv.conf.prevpn /etc/resolv.conf

    fi

    ;;



esac





source /etc/osso-af-init/af-defines.sh



for acct in `mc-tool list | grep sofiasip/sip`; do

        mc-tool update $acct clear:local-ip-address

done

andf finally default route script

Code:



#cat add_default_route.sh



#!/bin/sh



#if gprs0 up and no flagged default route ; then create one

#use with ipchange /etc/openvpn/add_default_route.sh in openvpn conf

#after setting script-security 2

gprsroute=`route | grep gprs` ; defroute=`route | grep default | grep G` ; if [ -n "$gprsroute" -a -z "$defroute" ]; then nexthop=`ifconfig gprs0 | grep "inet addr" | cut -d : -f 3 | cut -d " " -f 1` ; route add -host $nexthop dev gprs0 ; route add default gw $nexthop ; fi

Also wanted to add that this method works well if the sip provider is hosted outside the network. However in my case i have an asterisk server running inside my local network at 172.16.1.10. Thus i have to change my sip uri to reflect the internal asterisk server to 50@172.16.1.10 whereas normally i would simply use 50@xx.dyndns.org. This is a big pain because i have to keep switching between the two accounts depending on whether i am usng vpn or not. If somebody has any workaround please let me know.

Ok. The above issue is sorted. I use a Linksys WRT54GL router running dd-wrt. I had to simply add an extra arguement to dnsmasq as

Code:

address=/xx.dyndns.org/172.16.1.10