#!/bin/sh

# Copyright (C) 2014-2021 Daniel Baumann <daniel.baumann@open-infrastructure.net>
#
# SPDX-License-Identifier: GPL-3.0+
#
# 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, either version 3 of the License, or
# (at your option) any later version.
#
# 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.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <https://www.gnu.org/licenses/>.

set -e

. /etc/network-tools/config/ddns-client.conf

# alternatives handling for dig
if command -v kdig > /dev/null 2>&1
then
	# knot-dnsutils
	DIG="kdig +noadditional"
elif command -v dig > /dev/null 2>&1
then
	# bind9-dnsutils
	DIG="dig +noadditional"
else
	echo "'${HOOK}': need dig from bind9-dnsutils or knot-dnsutils" >&2
	exit 1
fi

NAMESERVER="$(echo ${NAMESERVERS} | awk '{ print $1 }')"

# Run
for NAMESERVER in ${NAMESERVERS}
do
	# shellcheck disable=SC2086
	${DIG} -k "${TSIG_KEYFILE}" @"${NAMESERVER}" AXFR "${ZONE}"
done | grep -E 'IN	(A|AAAA|TXT)	' | sort -u