misc_nixos-mailserver/scripts/check-mail-domain-dns.sh
Antoine Eiche 54a4d5d4f7 Add check-mail-domain-dns script
This script does some checks on the domain name DNS configuration.
It still lacks the DKIM and DMARC checks.
2020-05-13 22:24:54 +02:00

57 lines
1.4 KiB
Bash
Executable file

#!/usr/bin/env nix-shell
#!nix-shell -i bash --pure
#!nix-shell -p host
set -euo pipefail
if [ $# -ne 3 ];
then
echo "This script checks the DNS configuration of your mail domain"
echo "Usage: $0 DOMAIN FQDN SERVER_IP"
exit 1
fi
export DOMAIN=$1
export FQDN=$2
export SERVER_IP=$3
echo "Check '${DOMAIN}' as a DNS MX entry for '${FQDN}'"
if ! host -t MX "${DOMAIN}" | grep -q -e "${DOMAIN} mail is handled by .* ${FQDN}";
then
echo "Error: MX configuration is not correct"
host -t MX "${DOMAIN}"
exit 2
else
echo ok
fi
echo "Check '${FQDN}' resolves to '${SERVER_IP}'"
IP=$(host "$FQDN" | grep "has address" | cut -d" " -f4)
if [ "${IP}" != "${SERVER_IP}" ];
then
echo "Error: $FQDN should resolve to '${SERVER_IP}' (and not '$IP')"
exit 2
else
echo "ok"
fi
echo "Check the reverse dns entry for '${SERVER_IP}' point to the address of '${FQDN}'"
DN=$(host "$SERVER_IP" | cut -d" " -f5)
RDN=$(echo "${DN}" | xargs host | grep "has address" | cut -d" " -f4)
if [ "${SERVER_IP}" != "${RDN}" ];
then
echo "Error: reverse DNS is not correctly configured"
exit 2
else
echo "ok"
fi
echo "Check SPF is configured for ${DOMAIN}"
SPF=$(host -t TXT "${DOMAIN}")
if echo "${SPF}" | grep -q -e "v=spf1 .*+a:${FQDN}" || echo "${SPF}" | grep -q -e "v=spf1 .*ip4:${SERVER_IP}";
then
echo "ok"
else
echo "Error: SPF is not correctly configured"
echo " SPF TXT record: ${SPF}"
fi