#! /bin/bash
#
# dhcpd-restart-hook - script to restart dhcpd on virtual interfaces
#
# Copyright (C) 2009 SUSE LINUX Products GmbH, Nuernberg, Germany.
#
# Author(s): Marius Tomaschewski <mt@suse.de>, 2009
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# version 2 as published by the Free Software Foundation.
# 
# 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 <http://www.gnu.org/licenses/>
#
# Please send feedback via http://www.suse.de/feedback
#

set -e

unset ${!LC_*} LANUGUAGE
export LANG=POSIX
export PATH=/sbin:/usr/sbin:/usr/bin:/bin

SCRIPTNAME=${0##*/}

usage () {
        echo "usage: $SCRIPTNAME [<config>] <interface> [-o <options>]"
        echo ""
        echo "Any options are ignored"
        exit $R_USAGE
}

R_INTERNAL=1      # internal error, e.g. no config or missing scripts
cd /etc/sysconfig/network || exit $R_INTERNAL

case $1 in ""|-h|*help*) usage ;; esac
INTERFACE="$1"
if test "x$2" != x -a "x$2" != "x-o" ; then
        CONFIG=$INTERFACE
        INTERFACE="$2"
        shift
else
        CONFIG=$INTERFACE
fi
shift

mode=""
args=$(getopt -o "o:" -- "$@")
eval set -- "$args"
while [ $# -gt 0 ]; do
  case "$1" in
    --) shift; break;;
    -o) mode="$2"; shift;;
  esac
  shift
done

. /etc/sysconfig/network/config
if test -f /etc/sysconfig/network/scripts/functions ; then
	.  /etc/sysconfig/network/scripts/functions
fi

. /etc/sysconfig/dhcpd                   2>/dev/null
. /etc/sysconfig/network/ifcfg-"$CONFIG" 2>/dev/null || true

: ${DHCPD_IFUP_RESTART:=auto}
: ${DHCPD6_IFUP_RESTART:=auto}

iface_needs_restart()
{
        test -d /sys/class/net/$1/bridge  -o \
             -d /sys/class/net/$1/bonding -o \
             -f /proc/net/vlan/$1
}

dhcpv4_server_restart()
{
        #
        # don't do anything if we are disabled either
        # in the /etc/sysconfig/dhcpd or per interface
        # in the /etc/sysconfig/network/ifcfg-"$CONFIG"
        #
        test "$DHCPD_IFUP_RESTART" = no && return 0

        # don't restart for loopback interface
        case $INTERFACE in (lo) return 0 ;; esac

        restart_needed=$DHCPD_IFUP_RESTART
        if test -n "$DHCPD_INTERFACE" \
                -a "$restart_needed" != yes ;
        then
                for I in $DHCPD_INTERFACE ; do
                        test -n "$I" || continue

                        # don't restart when _one_ involved
                        # interface is not available/up yet
                        is_iface_up $I || return 0

                        # check if this interface is involved
                        if test "$I" = "$INTERFACE" ; then

                                # check if a restart is needed
                                if iface_needs_restart $I ; then
                                        restart_needed=yes
                                fi
                        fi
                done
        fi

        if test "$restart_needed" = yes ; then
          if test "`/usr/bin/systemctl --value -p SubState show dhcpd.service`" = "running"; then
            /usr/bin/systemctl restart dhcpd.service
          fi
        fi
}
dhcpv6_server_restart()
{
        #
        # don't do anything if we are disabled either
        # in the /etc/sysconfig/dhcpd or per interface
        # in the /etc/sysconfig/network/ifcfg-"$CONFIG"
        #
        test "$DHCPD6_IFUP_RESTART" = no && return 0

        # don't restart for loopback interface
        case $INTERFACE in (lo) return 0 ;; esac

        restart_needed=$DHCPD6_IFUP_RESTART
        if test -n "$DHCPD6_INTERFACE" \
                -a "$restart_needed" != yes ;
        then
                for I in $DHCPD6_INTERFACE ; do
                        test -n "$I" || continue

                        # don't restart when _one_ involved
                        # interface is not available/up yet
                        is_iface_up $I || return 0

                        # check if this interface is involved
                        if test "$I" = "$INTERFACE" ; then

                                # check if a restart is needed
                                if iface_needs_restart $I ; then
                                        restart_needed=yes
                                fi
                        fi
                done
        fi

        if test "$restart_needed" = yes ; then
          if test "`/usr/bin/systemctl --value -p SubState show dhcpd6.service`" = "running"; then
            /usr/bin/systemctl restart dhcpd6.service
          fi
        fi
}

case "$mode" in
*-up*)
	dhcpv4_server_restart
	dhcpv6_server_restart
;;
*-down*)
        # don't do anything
;;
*)
        echo "$SCRIPTNAME: don't know what to do" >&2
;;
esac