#!/bin/bash
echo "What DNS do you want to use with the VPN?"
	echo "   1) Current system resolvers"
	echo "   2) Google"
	echo "   3) OpenDNS"
	echo "   4) NTT"
	echo "   5) Hurricane Electric"
	echo "   6) You specify the DNS server IP-s"
	read -p "DNS [1-6]: " -e -i 6 DNS
	if [[ "$DNS" = '6' ]]; then
		echo "Please leave a space between DNS IP entries"
		read -e -p "Specify the DNS server IP-s. Space is the separator: " OWNDNS
	else
		echo ""
	fi

# DNS
	case $DNS in
		1) 
		# Obtain the resolvers from resolv.conf and use them for OpenVPN
		grep -v '#' /etc/resolv.conf | grep 'nameserver' | grep -E -o '[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}' | while read line; do
			echo "push \"dhcp-option DNS $line\"" >> ./server.conf
		done
		;;
		2) 
		echo 'push "dhcp-option DNS 8.8.8.8"' >> ./server.conf
		echo 'push "dhcp-option DNS 8.8.4.4"' >> ./server.conf
		;;
		3)
		echo 'push "dhcp-option DNS 208.67.222.222"' >> ./server.conf
		echo 'push "dhcp-option DNS 208.67.220.220"' >> ./server.conf
		;;
		4) 
		echo 'push "dhcp-option DNS 129.250.35.250"' >> ./server.conf
		echo 'push "dhcp-option DNS 129.250.35.251"' >> ./server.conf
		;;
		5) 
		echo 'push "dhcp-option DNS 74.82.42.42"' >> ./server.conf
		;;
		6)
	        for i in `echo $OWNDNS|tr " " "\n"`;
                	do
				echo 'push "dhcp-option DNS '"$i"'"' >> ./server.conf
	                done
                ;;
	esac
cat ./server.conf
rm -f ./server.conf