#! /bin/sh
#
# 6to4	Script to configure a 6to4 "tunnel" device
#
#		Written by Daniel Lawson <daniel@meta.net.nz>

PATH=/sbin:/bin:/usr/sbin:/usr/bin

test -f $DAEMON || exit 0

# Source configuration file
. /etc/default/6to4


start_6to4_tunnel() {
# GET EXTIF IP Address
  PPPIP=`ip -4 addr list $EXTIF | grep inet | awk '{ print $2'}`
# From IanKumlien:
# If you get a /netmask-bits suffix, then change the PPPIP line to:
# PPPIP=`ip -4 addr list $EXTIF | grep inet | awk '{ print $2 }' | cut -d/ -f1`
  echo $PPPIP 
# Set up the tunnel
  ip tunnel add ${IF} mode sit remote any local $PPPIP ttl 255
  ip link set dev ${IF} mtu 1472 up
}

start_routes() {
# Route outgoing 6to4 via the tunnel
  ip -6 route add 2002::/16 dev ${IF}

# If this is your only IPv6 connection, add some more routes as well:
  if [ ${ONLYCONN} == "yes" ]; then
    # This line seems necessary, but I've never found documented 
    # anywhere. Try without if you can.
    ip -6 route add ::/96 dev ${IF} metric 1 

    # Add a route toe the 6to4 Anycast address?
    ip -6 route add 2000::/3 via ::${GWADDR} dev tun6to4 metric 1
  fi
}
 
start_local_network() {
# Add a 6to4 Address to ${INTIF}
  if [ -n ${INTIF} ]; then
    ip -6 addr add $(printf "2002:%02x%02x:%02x%02x::1/64" $(echo ${PPPIP} | tr '.' ' ')) dev ${INTIF}
  fi
}

stop_local_network() {

  if [ -n ${INTIF} ]; then
    
# GET the *old* tunnel ip
    OLDIP=`ip -6 addr list dev ${IF} | grep inet6 | cut -d ":" -f 3 | cut -d '/' -f 1`
# Remove the route via ${INTIF}
    ip -6 route del $(printf "2002:%02x%02x:%02x%02x::/64" $(echo ${OLDIP} | tr '.' ' ')) dev ${INTIF}

# Remove the 6to4 IP assigned to ${INTIF}
    ip -6 addr del $(printf "2002:%02x%02x:%02x%02x::1/64" $(echo ${OLDIP} | tr '.' ' ')) dev ${INTIF}
  fi
}

stop_routes() {
 ip -6 route del 2002::/16 dev ${IF}
 if [ ${ONLYCONN} == "yes" ]; then
   ip -6 route del ::/96 dev ${IF} metric 1
   ip -6 route del 2000::/3 via ::${GWADDR} dev ${IF} metric 1
 fi
}

stop_6to4_tunnel() {
  ip -6 route flush dev ${IF}
  ip link set dev ${IF} down
	ip tunnel del ${IF} 
}

restart_6to4_ad () {
  [ "yes" == "${RADVD}" ] &&
    killall -1 radvd
}



case "$1" in
  start)
	echo -n "Setting up 6to4 IPv6 tunnel ($IF): "
  
  start_6to4_tunnel
  start_routes
  start_local_network
  restart_6to4_ad
	
  ;;
  stop)
	echo -n "Shutting down 6to4 IPv6 tunnel ($IF): "
 
  stop_local_network
  stop_routes
  stop_6to4_tunnel
  restart_6to4_ad
  
	;;
  restart|force-reload)
	echo -n "Resetting 6to4 IPv6 tunnel ($IF): "

  stop_local_network
  stop_routes
  stop_6to4_tunnel
  start_6to4_tunnel
  start_routes
  start_local_network
  restart_6to4_ad
  
  ;;
  *)
	echo "Usage: $0 {start|stop|restart|force-reload}" >&2
	exit 1
	;;
esac

exit 0