#!/bin/sh
# skeleton      example file to build /etc/rc.d/init.d/ scripts.
#
#               Written by Miquel van Smoorenburg <miquels@cistron.nl>.
#               Modified for Debian GNU/Linux 
#                 by Ian Murdock <imurdock@gnu.ai.mit.edu>.
#               Modified for RedHat Linux 
#                 by Bart Trojanowski <bart@jukie.net>.
#
# Version:      @(#)skeleton  1.6  11-Nov-1996  miquels@cistron.nl
#               vpn 1.7 20-Dec-1999 bart@jukie.net
#

#
# setup a path...
#
PATH=/usr/local/sbin:/sbin:/bin:/usr/sbin:/usr/bin:/usr/bin/X11/:

# Source RedHat function library.
. /etc/rc.d/init.d/functions


#
# required commands...
#
ROUTE=/sbin/route
PPPD=/usr/sbin/pppd
REDIR=/usr/local/bin/pty-redir
SSH=/usr/bin/ssh

test -f $PPPD  || exit -1
test -f $ROUTE || exit -2
test -f $REDIR || exit -3
test -f $SSH   || exit -4


#
#describe the connection we will be making to the slave machine...
#
SLAVE_HOSTNAME=gus.jukie.net
SLAVE_USERNAME=vpn
#SLAVE=${SLAVE_USERNAME}@${SLAVE_HOSTNAME}
SLAVE="${SLAVE_HOSTNAME} -l${SLAVE_USERNAME}"

#
# specify both ends of the ppp tunnel
#
PPPIP_LOCAL=192.168.0.1
PPPIP_REMOTE=192.168.0.2

#
# here is a list of all networks and their subnets that are to be
#  exported and imported
#
NETS_LOCAL="192.168.10.0/24 192.168.11.0/24"
NETS_REMOTE="192.168.5.0/24 192.168.6.0/24"


#
# globals...
#
TTYNAME=""
PPPDEV=""

#
# setup some functions...
#
start_remote_session() {
  
  ${REDIR} ${SSH} -t ${SLAVE} -o 'Batchmode yes' sudo \
    ${PPPD} nodetach noauth passive > /tmp/device 2>&1
  TTYNAME=`cat /tmp/device`
  
  if [ "${TTYNAME}" = "" ]; then
    rturn 1
  fi
  
  # allow for the connection to stabilize
  sleep 10s
  
  # test to make sure the is data on this device
  if [ -z ${TTYNAME} ]; then
    TTYNAME=""
    return 2
  fi
  
  return 0
}

start_local_session() {
  
  # store the before ppp device count
  PPPCNT=`/sbin/ifconfig | grep ppp | wc -l`
  
  # now launch the remote portion
  ${PPPD} ${TTYNAME} noauth ${PPPIP_LOCAL}:${PPPIP_REMOTE}
  
  # once again allow for stabilization
  sleep 5s
  
  # test to see if we got a ppp0 device
  if [ "${PPPCNT}" = `/sbin/ifconfig | grep ppp | wc -l` ]; then
    return 1
  fi

  PPPDEV=`/sbin/ifconfig | grep ppp | tail -n 1 | awk '{print $1}'`
  return 0
}


#
# START OF SCRIPT
#
case "$1" in
  start)
        # launch remote session
	echo -n "VPN: Starting remote connection on... "
	start_remote_session
	action "${TTYNAME}" test "( ${TTYNAME} )"
	if [ "${TTYNAME}" = "" ] ; then exit 1 ; fi
	
	# launch local session
	echo -n "VPN: Starting local connection on... "
	start_local_session
	action "${PPPDEV}" test "( ${PPPDEV} )"
	if [ "${PPPDEV}" = "" ] ; then exit 1 ; fi

	# setup local routes to slave nets
	for line in ${NETS_REMOTE} ; do
	  ${ROUTE} add -net ${line} gw ${PPPIP_LOCAL}
	done
	
	# setup routes on slave to local networks
	for line in ${NETS_LOCAL} ; do
	  $SSH -o 'Batchmode yes' ${SLAVE} sudo \
	    ${ROUTE} add -net ${line} gw ${PPPIP_REMOTE}
	done
	
    ;;
  stop)
        PID=`ps -ax | grep "${SSH} -t ${SLAVE} -o" | grep -v 'grep ' | awk '{print $1}'`
	if [ "${PID}" != "" ]; then
	  action "Shutting down vpn on pid '$PID':" kill $PID
	else
	  action "Failed to find PID for the connection" /bin/false
	fi
	
    ;;
  *)
    echo "Usage: vpn {start|stop}"
    exit 1
    ;;
esac

exit 0