#!/bin/sh

# Script to dispatch NetworkManager events
#
# Updates timesyncd configuration with NTP servers
# See NetworkManager(8) for further documentation of the dispatcher events.

# Note:
# RootDistanceMaxSec is set to 15 to override the default that is sometimes too
# low when talking to Windows Servers
set -e

[ -n "${CONNECTION_UUID}" ] || exit

INTERFACE="${1}"
ACTION="${2}"

TIMESYNCCONF="/etc/systemd/timesyncd.conf.d/${CONNECTION_UUID}.conf"
AUTOGEN_SIGNATURE="# File generated by $(basename $0)"

# Exit if file is not autogenerated
if [ -f "${TIMESYNCCONF}" ] &&  ! grep -q "${AUTOGEN_SIGNATURE}" "${TIMESYNCCONF}"; then
	exit 0
fi

case "${ACTION}" in
    up | dhcp4-change | dhcp6-change)
        [ -n "${DHCP4_NTP_SERVERS}" ] || exit
	mkdir -p $(dirname ${TIMESYNCCONF})
        cat<<EOF > ${TIMESYNCCONF}
${AUTOGEN_SIGNATURE}

[Time]
NTP=${DHCP4_NTP_SERVERS}
RootDistanceMaxSec=15
EOF
        systemctl restart systemd-timesyncd
       ;;
    down)
        rm -f "${TIMESYNCCONF}"
        systemctl restart systemd-timesyncd
        ;;
esac