#! /bin/sh
# iproute2 version, default updown script
# Copyright (C) 2002. Michael Richardson
# 
# 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.  See <http://www.fsf.org/copyleft/gpl.txt>.
# 
# 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.
#
# RCSID $Id: _updown.ip2.in,v 1.2 2003/08/18 16:34:29 mcr Exp $



# CAUTION:  Installing a new version of FreeS/WAN will install a new
# copy of this script, wiping out any custom changes you make.  If
# you need changes, make a copy of this under another name, and customize
# that, and use the (left/right)updown parameters in ipsec.conf to make
# FreeS/WAN use yours instead of this default one.


# things that this script gets (from ipsec_pluto(8) man page)
#
#
#      PLUTO_VERSION
#              indicates  what  version of this interface is being
#              used.  This document describes version  1.1.   This
#              is upwardly compatible with version 1.0.
#
#       PLUTO_VERB
#              specifies the name of the operation to be performed
#              (prepare-host,r prepare-client, up-host, up-client,
#              down-host,  or down-client).  If the address family
#              for security gateway to security gateway communica
#              tions is IPv6, then a suffix of -v6 is added to the
#              verb.
#
#       PLUTO_CONNECTION
#              is the name of the  connection  for  which  we  are
#              routing.
#
#       PLUTO_NEXT_HOP
#              is the next hop to which packets bound for the peer
#              must be sent.
#
#       PLUTO_INTERFACE
#              is the name of the ipsec interface to be used.
#
#       PLUTO_ME
#              is the IP address of our host.
#
#       PLUTO_MY_CLIENT
#              is the IP address / count of our client subnet.  If
#              the  client  is  just  the  host,  this will be the
#              host's own IP address / max (where max  is  32  for
#              IPv4 and 128 for IPv6).
#
#       PLUTO_MY_CLIENT_NET
#              is the IP address of our client net.  If the client
#              is just the host, this will be the  host's  own  IP
#              address.
#
#       PLUTO_MY_CLIENT_MASK
#              is  the  mask for our client net.  If the client is
#              just the host, this will be 255.255.255.255.
#
#       PLUTO_PEER
#              is the IP address of our peer.
#
#       PLUTO_PEER_CLIENT
#              is the IP address / count of the peer's client sub
#              net.   If the client is just the peer, this will be
#              the peer's own IP address / max (where  max  is  32
#              for IPv4 and 128 for IPv6).
#
#       PLUTO_PEER_CLIENT_NET
#              is the IP address of the peer's client net.  If the
#              client is just the peer, this will  be  the  peer's
#              own IP address.
#
#       PLUTO_PEER_CLIENT_MASK
#              is  the  mask  for  the  peer's client net.  If the
#              client   is   just   the   peer,   this   will   be
#              255.255.255.255.
#
# PLUTO_PEER_SOURCEIP
# PLUTO_CONNECTION_TYPE
#

# check interface version
case "$PLUTO_VERSION" in
1.[0])	# Older Pluto?!?  Play it safe, script may be using new features.
	echo "$0: obsolete interface version \`$PLUTO_VERSION'," >&2
	echo "$0: 	called by obsolete Pluto?" >&2
	exit 2
	;;
1.*)	;;
*)	echo "$0: unknown interface version \`$PLUTO_VERSION'" >&2
	exit 2
	;;
esac

# check parameter(s)
case "$1:$*" in
':')			# no parameters
	;;
ipfwadm:ipfwadm)	# due to (left/right)firewall; for default script only
	;;
custom:*)		# custom parameters (see above CAUTION comment)
	;;
*)	echo "$0: unknown parameters \`$*'" >&2
	exit 2
	;;
esac

# utility functions for route manipulation
# Meddling with this stuff should not be necessary and requires great care.
uproute() {
	doroute add
}
downroute() {
	doroute del
}
doroute() {
	parms="$PLUTO_PEER_CLIENT"
	parms2=""
	if [ -n "$PLUTO_NEXT_HOP" ]
	then
	    parms2="via $PLUTO_NEXT_HOP"
	fi
	parms2="$parms2 dev $PLUTO_INTERFACE"

	if [ -z "$PLUTO_PEER_SOURCEIP" ]
	then
	    if [ -f /etc/sysconfig/defaultsource ]
	    then
		. /etc/sysconfig/defaultsource
		if [ -n "$DEFAULTSOURCE" ]
		then
		    PLUTO_PEER_SOURCEIP=$DEFAULTSOURCE
		fi
	    fi
        fi

	if [ -n "$PLUTO_PEER_SOURCEIP" ]
	then
	    parms2="$parms2 src $DEFAULTSOURCE"
	fi
	case "$PLUTO_PEER_CLIENT_NET/$PLUTO_PEER_CLIENT_MASK" in
	"0.0.0.0/0.0.0.0")
		# need to provide route that eclipses default, without 
		# replacing it.
		it="ip route $1 0.0.0.0/1 $parms2 &&"
		it="$it ip route $1 128.0.0.0/1 $parms2"
		ip route $1 0.0.0.0/1 $parms2 &&
		    ip route $1 128.0.0.0/1 $parms2
		;;
	*)	it="ip route $1 $parms $parms2"
		ip route $1 $parms $parms2
		;;
	esac
	st=$?
	if test $st -ne 0
	then
		# route has already given its own cryptic message
		echo "$0: \`$it' failed" >&2
		if test " $1 $st" = " add 7"
		then
			# another totally undocumented interface -- 7 and
			# "SIOCADDRT: Network is unreachable" means that
			# the gateway isn't reachable.
			echo "$0: (incorrect or missing nexthop setting??)" >&2
		fi
	fi
	return $st
}



# the big choice
case "$PLUTO_VERB:$1" in
prepare-host:*|prepare-client:*)
	# delete possibly-existing route (preliminary to adding a route)
	case "$PLUTO_PEER_CLIENT_NET/$PLUTO_PEER_CLIENT_MASK" in
	"0.0.0.0/0.0.0.0")
		# need to provide route that eclipses default, without 
		# replacing it.
		parms1="0.0.0.0/1"
		parms2="128.0.0.0/1"
		it="ip route del $parms1 2>&1 ; ip route del $parms2 2>&1"
		oops="`ip route del $parms1 2>&1 ; ip route del $parms2 2>&1`"
		;;
	*)
		parms="$PLUTO_PEER_CLIENT"
		it="ip route del $parms 2>&1"
		oops="`ip route del $parms 2>&1`"
		;;
	esac
	status="$?"
	if test " $oops" = " " -a " $status" != " 0"
	then
		oops="silent error, exit status $status"
	fi
	case "$oops" in
	'RTNETLINK answers: No such process'*)
		# This is what route (currently -- not documented!) gives
		# for "could not find such a route".
		oops=
		status=0
		;;
	esac
	if test " $oops" != " " -o " $status" != " 0"
	then
		echo "$0: \`$it' failed ($oops)" >&2
	fi
	exit $status
	;;
route-host:*|route-client:*)
	# connection to me or my client subnet being routed
	uproute
	;;
unroute-host:*|unroute-client:*)
	# connection to me or my client subnet being unrouted
	downroute
	;;
up-host:*)
	# connection to me coming up
	# If you are doing a custom version, firewall commands go here.
	;;
down-host:*)
	# connection to me going down
	# If you are doing a custom version, firewall commands go here.
	;;
up-client:)
	# connection to my client subnet coming up
	# If you are doing a custom version, firewall commands go here.
	;;
down-client:)
	# connection to my client subnet going down
	# If you are doing a custom version, firewall commands go here.
	;;
up-client:ipfwadm)
	# connection to client subnet, with (left/right)firewall=yes, coming up
	# This is used only by the default updown script, not by your custom
	# ones, so do not mess with it; see CAUTION comment up at top.
	ipfwadm -F -i accept -b -S $PLUTO_MY_CLIENT_NET/$PLUTO_MY_CLIENT_MASK \
		-D $PLUTO_PEER_CLIENT_NET/$PLUTO_PEER_CLIENT_MASK
	;;
down-client:ipfwadm)
	# connection to client subnet, with (left/right)firewall=yes, going down
	# This is used only by the default updown script, not by your custom
	# ones, so do not mess with it; see CAUTION comment up at top.
	ipfwadm -F -d accept -b -S $PLUTO_MY_CLIENT_NET/$PLUTO_MY_CLIENT_MASK \
		-D $PLUTO_PEER_CLIENT_NET/$PLUTO_PEER_CLIENT_MASK
	;;
*)	echo "$0: unknown verb \`$PLUTO_VERB' or parameter \`$1'" >&2
	exit 1
	;;
esac
