#!/bin/sh
#
#     (c) 1999,2000,2001,2002,2003,2004,2005,2014 - Tom Eastep (teastep@shorewall.net)
#
#	On most distributions, this file should be called /etc/init.d/shorewall.
#
#	Complete documentation is available at https://shorewall.org
#
#       This program is part of Shorewall.
#
#	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 2 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 <http://www.gnu.org/licenses/>.
#
#	Commands are:
#
#	   ipv6 start			  Starts ipv6
#	   ipv6 restart			  Restarts ipv6
#	   ipv6 reload			  Restarts ipv6
#	   ipv6 stop			  Stops ipv6
#	   ipv6 status		          Displays ipv6 status
#

# chkconfig: 2345 4 99
# description: Configure a 6to4 tunnel

### BEGIN INIT INFO
# Provides:	  ipv6
# Required-Start: boot.udev
# Required-Stop:
# Default-Start:  2 3 5
# Default-Stop:	  0 1 6
# Description:	  starts and stops ipv6
### END INIT INFO

################################################################################
# Interfaces to be configured
#
# External Interface
#
SIT="sit1"
#
# If the external interface is a 6to4 tunnel (sit device) then specify the
# IPv4 address here. Otherwise, leave this variable enpty
#
ADDRESS4=206.124.146.180
#
# Internal interfaces of the firewall -- space separated
#
INTERFACES="eth0"
#
# Bits 48-63 of the first internal interface address. Will be incremented
# for each additional internal interface.
#
SLA=1
#
# Default Gateway -- for 6to4, this is ::192.88.99.1
#
GATEWAY=::192.88.99.1
#
# For 6to4 configurations, the ADDRESS6 variable is calculated as follows.
#
# For other configurations, you need to specify ADDRESS6.
#
# ADDRESS6 is assumed to be a 48-bit prefix. If not, then the logic for
# addressing on the internal networks needs to be replaced below.
#
ADDRESS6=$(printf 2002:%02x%02x:%02x%02x $(echo $ADDRESS4 | tr '.' ' '))
#
# The global address of $SIT
#
SITADDR=${ADDRESS6}::1
################################################################################
# Give Usage Information						       #
################################################################################
usage() {
    echo "Usage: $0 start|stop|reload|restart|status"
    exit 1
}
################################################################################
# Start IPv6
################################################################################
do_start()
{
    local interface

    if [ -n "$SIT" ]; then
	if [ -n "$ADDRESS4" ]; then
	    #
	    # 6to4 -- create tunnel
	    #
	    modprobe sit
	    /sbin/ip tunnel add $SIT mode sit ttl 64 remote any local $ADDRESS4
	fi
	#
	# Configure the external IP address
	#
	/sbin/ip -6 addr add ${SITADDR} dev $SIT
	[ -n "$ADDRESS4" ] && /sbin/ip link set dev $SIT up
	[ -n "$GATEWAY"  ] && /sbin/ip -6 route add default via $GATEWAY dev $SIT metric 1
    fi

    for interface in $INTERFACES ; do
	/sbin/ip -6 addr add ${ADDRESS6}:$SLA::1/64 dev $interface
	SLA=$(($SLA + 1 ))
    done
}
################################################################################
# Stop IPv6
################################################################################
do_stop()
{
    local interface
    local device
    device=1
    local original_sla
    original_sli=$SLA

    if [ -n "$SIT" ]; then
	if [ -n "$ADDRESS4" ]; then
	    /sbin/ip link set $SIT down
	else
	    /sbin/ip -6 addr del ${SITADDR} dev $SIT
	    [ -n "$GATEWAY" ] && /sbin/ip -6 route del default via $GATEWAY dev $SIT metric 1
	fi
	[ -n "$ADDRESS4" ] && /sbin/ip tunnel del $SIT
    fi

    for interface in $INTERFACES; do
	/sbin/ip -6 addr del ${ADDRESS6}:$SLA::1/64 dev $interface
	SLA=$(($SLA + 1 ))
    done

    SLA=$original_sla #In case this is a restart/reload
}
################################################################################
# E X E C U T I O N    B E G I N S   H E R E				       #
################################################################################
command="$1"

case "$command" in
    start)
	do_start
	;;
    stop)
	do_stop
	;;
    restart|reload)
	do_stop
	do_start
	;;
    status)
	/sbin/ip -6 addr list
	/sbin/ip -6 route list
	;;
    *)
	usage
	;;
esac