#!/bin/sh

#  

#  This script uses the named D-BUS support, which must be enabled in

#  the running named with the named '-D' option, to get and print the

#  list of forwarding zones in the running server.

#

#  It accepts an optional <zone> first argument which is the DNS name

#  of the zone whose forwarders (if any) will be retrieved.

#

#  If no zone argument is specified, all forwarding zones will be listed.

#

#  Usage: namedGetForwarders [-n -r] [ <zone> ]

#    -n : output forward zone statements for named.conf

#    -r : output in resolv.conf format

#       : no -r or -n: just list the forwarders

#

#  This script is based on perl script of Jason Vas Dias <jvdias@redhat.com>. 

#

#  Copyright(C) Baris Cicek <baris@nerd.com.tr> Nerd Software. 2007

#

#  This program is free software; you can redistribute it and/or modify

#  it under the terms of the GNU General Public License as published by

#  the Free Software Foundation at

#           http://www.fsf.org/licensing/licenses/gpl.txt

#  and included in this software distribution as the "LICENSE" file.

#

#  This program is distributed in the hope that it will be useful,

#  but WITHOUT ANY WARRANTY; without even the implied warranty of

#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

#  GNU General Public License for more details.

declare -a zones;

declare -a servers;

declare -a ports;

declare -a only; 

output_format='plain';

zonecnt=0;

function push () {

	local array 

	array=( `echo $1` );

	array[${#array[*]}]=$2;

	echo ${array[@]};

}

function concat () { 

	local string

	while [ $# -gt 0 ]; do

		string=${string}$1;

		shift;

	done

	echo $string;

}

if  [ $# -ge 0 ]; then

	if [ "$1" == "-r" ]; then

		output_format='resolv';

		shift;

	elif [ "$1" == "-n" ]; then

		output_format='named';

		shift;

	fi

	zone="";

	for arg in $*; do

		zone=$(push "$zone" " string:'$arg'");

	done

fi 

DNS=`/bin/dbus-send --system --type=method_call --print-reply --reply-timeout=20000 --dest=com.redhat.named /com/redhat/named com.redhat.named.text.GetForwarders $zone`;

if [ $? -ne 0 ]; then

	echo -e "dbus-send failed: $? $!";

	exit 1;

fi

IFS=$'\n'

for line in $DNS; do

	match_ip=$( echo "$line" | awk --re-interval '{ match ($0, /([[:digit:]]{1,3})\.([[:digit:]]{1,3})\.([[:digit:]]{1,3})\.([[:digit:]]{1,3})/, a); printf "%s.%s.%s.%s", substr($0, a[1, "start"], a[1, "length"]), substr($0, a[2, "start"], a[2, "length"]), substr($0, a[3, "start"], a[3, "length"]), substr($0, a[4, "start"], a[4, "length"]);}' );

	match_port=$( echo "$line" | awk '{ match ($0, /\"([[:digit:]]+)\"$/, a); printf "%s", substr($0, a[1, "start"], a[1,"length"]);}' );

	match_string=$( echo "$line" | awk '{ match ($0, /string.+\"([^\"]+)\"$/, a); printf "%s", substr($0, a[1, "start"], a[1,"length"]);}' );

	if [ "$match_ip" != "" ] && [ "$match_ip" != "..." ]; then

		servers[$zonecnt]=$(push "${servers[$zonecnt]}" "$match_ip");

	elif [ "$match_port" != "" ]; then 

		ports[$zonecnt]=$(push "${ports[$zonecnt]}" "$match_port");

	elif [ "$match_string" == "only" ]; then

		only[$zonecnt]="1"; 

	elif [ "$match_string" != "" ] && [ "$match_string" != "first" ]; then

			zonecnt=$((zonecnt + 1));

			zones[$zonecnt]="$match_string";

	fi

done

if [ "$output_format" == "resolv" ]; then

# resolv.conf style:

	search_line='search';

	nameserver_lines='';

	for index in $(seq 1 $zonecnt); do

		if [ "` echo ${zones[$index]} | awk ' /\.in-addr\.arpa$/ { print $0 }'`" == '' ]; then

			  search_line=$(push "$search_line" "${zones[$index]}");

		fi 

		IFS=$' ';

		for ns in ${servers[$index]}; do

		  nameserver_lines=$(concat "$nameserver_lines" "\nnameserver " "$ns");

		done

	done

	echo -n $search_line;

	echo -e $nameserver_lines;

elif [ "$output_format" == "named" ]; then

# named.conf style:

	zone_lines='';

	for index in $(seq 1 $zonecnt); do

		zone_line=$(concat 'zone "' "${zones[$index]}" '." IN { type forward; forwarders { ');

		srvcnt=1;

		IFS=$' '; 

		for ns in ${servers[$index]}; do

			srvport=$(eval "echo ${ports[$index]} | awk '{ print \$${srvcnt} }'");

			if [ "$srvport" != "53" ]; then

				zone_line=$(concat "$zone_line" " $ns port $srvport;");

			else 

				zone_line=$(concat "$zone_line" " $ns;");

			fi

			srvcnt=$((srvcnt+1)); 

		done

		zone_line=$(concat "$zone_line" " };");

		if [ "${only[$index]}" == '1' ]; then

			zone_line=$(concat "$zone_line" " forward only;");

		fi

		zone_line=$(concat "$zone_line" " };");

		zone_lines=$(concat "$zone_lines" "$zone_line\n");

	done

	echo -e ${zone_lines%\\n};

elif [ "$output_format" == "plain" ]; then

# just list:

	output='';

	for index in $(seq 1 $zonecnt); do

		output=$(concat "$output" "${zones[$index]}" "\n");

		if [ "${only[$index]}" == "1" ]; then

			output=$(concat "$output" "\t" "forward only" "\n");

		fi

		srvcnt=1;

		IFS=$' ';

		for ns in ${servers[$index]}; do

			srvport=$(eval "echo ${ports[$index]} | awk '{ print \$${srvcnt} }'");

			if [ "$srvport" != "53" ]; then

				output=$(concat "$output" "\t" "$ns:$srvport" "\n");

			else

				output=$(concat "$output" "\t" "$ns" "\n");

			fi

			srvcnt=$((srvcnt+1));

		done	

	done

	echo -e ${output%\\n};

fi