update-resolv-conf

#!/bin/bash
# 
# Parses DHCP options from openvpn to update resolv.conf
# To use set as 'up' and 'down' script in your openvpn *.conf:
# up /etc/openvpn/update-resolv-conf
# down /etc/openvpn/update-resolv-conf
# 
# Used snippets of resolvconf script by Thomas Hood <jdthood@yahoo.co.uk> 
# and Chris Hanson
# Licensed under the GNU GPL.  See /usr/share/common-licenses/GPL. 
#
# Adjusted for openSUSE and its 'netconfig' component
# using dirty tricks by multiple1902. 
# Omitted the 'DOMAIN' part.
#
# 05/2006 chlauber@bnc.ch
# 01/2012 multiple1902@gmail.com
# 
# Example envs set from openvpn:
# foreign_option_1='dhcp-option DNS 193.43.27.132'
# foreign_option_2='dhcp-option DNS 193.43.27.133'
# foreign_option_3='dhcp-option DOMAIN be.bnc.ch'

NETCONFIG="/sbin/netconfig"
CONFIGFILE="/var/run/netconfig/NetworkManager.netconfig"

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
		fi
	done
    cp $CONFIGFILE{,.bak}
    grep -v DNSSERVERS $CONFIGFILE.bak > $CONFIGFILE
    echo "DNSSERVERS='$IF_DNS_NAMESERVERS'" >> $CONFIGFILE
    $NETCONFIG update -f
	;;
down)
    cp $CONFIGFILE{.bak,}
    $NETCONFIG update -f
	;;
esac