#!/bin/sh
# updown script setting inbound marks on ESP traffic in the mangle chain
#
# Copyright (C) 2003-2004 Nigel Meteringham
# Copyright (C) 2003-2004 Tuomo Soini
# Copyright (C) 2002-2004 Michael Richardson
# Copyright (C) 2005-2010 Andreas Steffen <andreas.steffen@strongswan.org>
#
# 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.

# CAUTION:  Installing a new version of strongSwan 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
# strongSwan use yours instead of this default one.

#      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, 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_INTERFACE
#              is the name of the ipsec interface to be used.
#
#       PLUTO_REQID
#              is the requid of the AH|ESP policy
#
#       PLUTO_PROTO
#              is the negotiated IPsec protocol, ah|esp
#
#       PLUTO_IPCOMP
#              is not empty if IPComp was negotiated
#
#       PLUTO_UNIQUEID
#              is the unique identifier of the associated IKE_SA
#
#       PLUTO_ME
#              is the IP address of our host.
#
#       PLUTO_MY_ID
#              is the ID 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_SOURCEIP
#       PLUTO_MY_SOURCEIP4_$i
#       PLUTO_MY_SOURCEIP6_$i
#              contains IPv4/IPv6 virtual IP received from a responder,
#              $i enumerates from 1 to the number of IP per address family.
#              PLUTO_MY_SOURCEIP is a legacy variable and equal to the first
#              virtual IP, IPv4 or IPv6.
#
#       PLUTO_MY_PROTOCOL
#              is the IP protocol that will be transported.
#
#       PLUTO_MY_PORT
#              is  the  UDP/TCP  port  to  which  the IPsec SA  is
#              restricted on our side.  For ICMP/ICMPv6 this contains the
#              message type, and PLUTO_PEER_PORT the message code.
#
#       PLUTO_PEER
#              is the IP address of our peer.
#
#       PLUTO_PEER_ID
#              is the ID of our peer.
#
#       PLUTO_PEER_CLIENT
#              is the IP address / count of the peer's client sub-
#              net.   If the client is just the peer, this will be
#              the peer's own IP address / max (where  max  is  32
#              for IPv4 and 128 for IPv6).
#
#       PLUTO_PEER_SOURCEIP
#       PLUTO_PEER_SOURCEIP4_$i
#       PLUTO_PEER_SOURCEIP6_$i
#              contains IPv4/IPv6 virtual IP sent to an initiator,
#              $i enumerates from 1 to the number of IP per address family.
#              PLUTO_PEER_SOURCEIP is a legacy variable and equal to the first
#              virtual IP, IPv4 or IPv6.
#
#       PLUTO_PEER_PROTOCOL
#              is the IP protocol that will be transported.
#
#       PLUTO_PEER_PORT
#              is  the  UDP/TCP  port  to  which  the IPsec SA  is
#              restricted on the peer side.  For ICMP/ICMPv6 this contains the
#              message code, and PLUTO_MY_PORT the message type.
#
#       PLUTO_XAUTH_ID
#              is an optional user ID employed by the XAUTH protocol
#
#       PLUTO_MARK_IN
#              is an optional XFRM mark set on the inbound IPsec SA
#
#       PLUTO_MARK_OUT
#              is an optional XFRM mark set on the outbound IPsec SA
#
#       PLUTO_UDP_ENC
#              contains the remote UDP port in the case of ESP_IN_UDP
#              encapsulation
#
#       PLUTO_DNS4_$i
#       PLUTO_DNS6_$i
#              contains IPv4/IPv6 DNS server attribute received from a
#              responder, $i enumerates from 1 to the number of servers per
#              address family.
#

# define a minimum PATH environment in case it is not set
PATH="/sbin:/bin:/usr/sbin:/usr/bin:/usr/sbin:/usr/local/sbin"
export PATH

# comment to disable logging VPN connections to syslog
VPN_LOGGING=1
#
# tag put in front of each log entry:
TAG=vpn
#
# syslog facility and priority used:
FAC_PRIO=local0.notice
#
# to create a special vpn logging file, put the following line into
# the syslog configuration file /etc/syslog.conf:
#
# local0.notice                   -/var/log/vpn

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

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

IPSEC_POLICY="-m policy --pol ipsec --proto $PLUTO_PROTO --reqid $PLUTO_REQID"
IPSEC_POLICY_IN="$IPSEC_POLICY --dir in"
IPSEC_POLICY_OUT="$IPSEC_POLICY --dir out"

# use protocol specific options to set ports
case "$PLUTO_MY_PROTOCOL" in
1)	# ICMP
	ICMP_TYPE_OPTION="--icmp-type"
	;;
58)	# ICMPv6
	ICMP_TYPE_OPTION="--icmpv6-type"
	;;
*)
	;;
esac

# are there port numbers?
if [ "$PLUTO_MY_PORT" != 0 ]
then
	if [ -n "$ICMP_TYPE_OPTION" ]
	then
		S_MY_PORT="$ICMP_TYPE_OPTION $PLUTO_MY_PORT"
		D_MY_PORT="$ICMP_TYPE_OPTION $PLUTO_MY_PORT"
	else
		S_MY_PORT="--sport $PLUTO_MY_PORT"
		D_MY_PORT="--dport $PLUTO_MY_PORT"
	fi
fi
if [ "$PLUTO_PEER_PORT" != 0 ]
then
	if [ -n "$ICMP_TYPE_OPTION" ]
	then
		# the syntax is --icmp[v6]-type type[/code], so add it to the existing option
		S_MY_PORT="$S_MY_PORT/$PLUTO_PEER_PORT"
		D_MY_PORT="$D_MY_PORT/$PLUTO_PEER_PORT"
	else
		S_PEER_PORT="--sport $PLUTO_PEER_PORT"
		D_PEER_PORT="--dport $PLUTO_PEER_PORT"
	fi
fi

# is there an inbound mark to be set?
if [ -n "$PLUTO_MARK_IN" ]
then
	if [ -n "$PLUTO_UDP_ENC" ]
	then
		SET_MARK="-p udp --sport $PLUTO_UDP_ENC"
	else
		SET_MARK="-p $PLUTO_PROTO"
	fi
	SET_MARK="$SET_MARK -s $PLUTO_PEER -j MARK --set-mark $PLUTO_MARK_IN"
fi

# resolve octal escape sequences
PLUTO_MY_ID=`printf "$PLUTO_MY_ID"`
PLUTO_PEER_ID=`printf "$PLUTO_PEER_ID"`

case "$PLUTO_VERB:$1" in
up-host:)
	# connection to me coming up
	# If you are doing a custom version, firewall commands go here.
	if [ -n "$PLUTO_MARK_IN" ]
	then
	    iptables -t mangle -A PREROUTING $SET_MARK
	fi
	iptables -I INPUT 1 -i $PLUTO_INTERFACE -p $PLUTO_MY_PROTOCOL \
	    -s $PLUTO_PEER_CLIENT $S_PEER_PORT \
	    -d $PLUTO_ME $D_MY_PORT $IPSEC_POLICY_IN -j ACCEPT
	iptables -I OUTPUT 1 -o $PLUTO_INTERFACE -p $PLUTO_PEER_PROTOCOL \
	    -s $PLUTO_ME $S_MY_PORT $IPSEC_POLICY_OUT \
	    -d $PLUTO_PEER_CLIENT $D_PEER_PORT -j ACCEPT
	#
	# allow IPIP traffic because of the implicit SA created by the kernel if
	# IPComp is used (for small inbound packets that are not compressed)
	if [ -n "$PLUTO_IPCOMP" ]
	then
	  iptables -I INPUT 1 -i $PLUTO_INTERFACE -p 4 \
	      -s $PLUTO_PEER -d $PLUTO_ME $IPSEC_POLICY_IN -j ACCEPT
	fi
	#
	# log IPsec host connection setup
	if [ $VPN_LOGGING ]
	then
	  if [ "$PLUTO_PEER_CLIENT" = "$PLUTO_PEER/32" ]
	  then
	    logger -t $TAG -p $FAC_PRIO \
	      "+ $PLUTO_PEER_ID $PLUTO_PEER -- $PLUTO_ME"
	  else
	    logger -t $TAG -p $FAC_PRIO \
	      "+ $PLUTO_PEER_ID $PLUTO_PEER_CLIENT == $PLUTO_PEER -- $PLUTO_ME"
	  fi
	fi
	;;
down-host:)
	# connection to me going down
	# If you are doing a custom version, firewall commands go here.
	if [ -n "$PLUTO_MARK_IN" ]
	then
	    iptables -t mangle -D PREROUTING $SET_MARK
	fi
	iptables -D INPUT -i $PLUTO_INTERFACE -p $PLUTO_MY_PROTOCOL \
	    -s $PLUTO_PEER_CLIENT $S_PEER_PORT \
	    -d $PLUTO_ME $D_MY_PORT $IPSEC_POLICY_IN -j ACCEPT
	iptables -D OUTPUT -o $PLUTO_INTERFACE -p $PLUTO_PEER_PROTOCOL \
	    -s $PLUTO_ME $S_MY_PORT $IPSEC_POLICY_OUT \
	    -d $PLUTO_PEER_CLIENT $D_PEER_PORT -j ACCEPT
	#
	# IPIP exception teardown
	if [ -n "$PLUTO_IPCOMP" ]
	then
	  iptables -D INPUT -i $PLUTO_INTERFACE -p 4 \
	      -s $PLUTO_PEER -d $PLUTO_ME $IPSEC_POLICY_IN -j ACCEPT
	fi
	#
	# log IPsec host connection teardown
	if [ $VPN_LOGGING ]
	then
	  if [ "$PLUTO_PEER_CLIENT" = "$PLUTO_PEER/32" ]
	  then
	    logger -t $TAG -p $FAC_PRIO -- \
	      "- $PLUTO_PEER_ID $PLUTO_PEER -- $PLUTO_ME"
	  else
	    logger -t $TAG -p $FAC_PRIO -- \
	    "- $PLUTO_PEER_ID $PLUTO_PEER_CLIENT == $PLUTO_PEER -- $PLUTO_ME"
	  fi
	fi
	;;
up-client:)
	# connection to my client subnet coming up
	# If you are doing a custom version, firewall commands go here.
	if [ -n "$PLUTO_MARK_IN" ]
	then
	    iptables -t mangle -A PREROUTING $SET_MARK
	fi
	if [ "$PLUTO_PEER_CLIENT" != "$PLUTO_MY_SOURCEIP/32" ]
	then
	  iptables -I FORWARD 1 -o $PLUTO_INTERFACE -p $PLUTO_PEER_PROTOCOL \
	      -s $PLUTO_MY_CLIENT $S_MY_PORT \
	      -d $PLUTO_PEER_CLIENT $D_PEER_PORT $IPSEC_POLICY_OUT -j ACCEPT
	  iptables -I FORWARD 1 -i $PLUTO_INTERFACE -p $PLUTO_MY_PROTOCOL \
	      -s $PLUTO_PEER_CLIENT $S_PEER_PORT \
	      -d $PLUTO_MY_CLIENT $D_MY_PORT $IPSEC_POLICY_IN -j ACCEPT
	fi
	#
	# a virtual IP requires an INPUT and OUTPUT rule on the host
	# or sometimes host access via the internal IP is needed
	if [ -n "$PLUTO_MY_SOURCEIP" -o -n "$PLUTO_HOST_ACCESS" ]
	then
	  iptables -I INPUT 1 -i $PLUTO_INTERFACE -p $PLUTO_MY_PROTOCOL \
	      -s $PLUTO_PEER_CLIENT $S_PEER_PORT \
	      -d $PLUTO_MY_CLIENT $D_MY_PORT $IPSEC_POLICY_IN -j ACCEPT
	  iptables -I OUTPUT 1 -o $PLUTO_INTERFACE -p $PLUTO_PEER_PROTOCOL \
	      -s $PLUTO_MY_CLIENT $S_MY_PORT \
	      -d $PLUTO_PEER_CLIENT $D_PEER_PORT $IPSEC_POLICY_OUT -j ACCEPT
	fi
	#
	# allow IPIP traffic because of the implicit SA created by the kernel if
	# IPComp is used (for small inbound packets that are not compressed).
	# INPUT is correct here even for forwarded traffic.
	if [ -n "$PLUTO_IPCOMP" ]
	then
	  iptables -I INPUT 1 -i $PLUTO_INTERFACE -p 4 \
	      -s $PLUTO_PEER -d $PLUTO_ME $IPSEC_POLICY_IN -j ACCEPT
	fi
	#
	# log IPsec client connection setup
	if [ $VPN_LOGGING ]
	then
	  if [ "$PLUTO_PEER_CLIENT" = "$PLUTO_PEER/32" ]
	  then
	    logger -t $TAG -p $FAC_PRIO \
	      "+ $PLUTO_PEER_ID $PLUTO_PEER -- $PLUTO_ME == $PLUTO_MY_CLIENT"
	  else
	    logger -t $TAG -p $FAC_PRIO \
	      "+ $PLUTO_PEER_ID $PLUTO_PEER_CLIENT == $PLUTO_PEER -- $PLUTO_ME == $PLUTO_MY_CLIENT"
	  fi
	fi
	;;
down-client:)
	# connection to my client subnet going down
	# If you are doing a custom version, firewall commands go here.
	if [ -n "$PLUTO_MARK_IN" ]
	then
	    iptables -t mangle -D PREROUTING $SET_MARK
	fi
	if [ "$PLUTO_PEER_CLIENT" != "$PLUTO_MY_SOURCEIP/32" ]
	then
	  iptables -D FORWARD -o $PLUTO_INTERFACE -p $PLUTO_PEER_PROTOCOL \
	      -s $PLUTO_MY_CLIENT $S_MY_PORT \
	      -d $PLUTO_PEER_CLIENT $D_PEER_PORT \
	         $IPSEC_POLICY_OUT -j ACCEPT
	  iptables -D FORWARD -i $PLUTO_INTERFACE -p $PLUTO_MY_PROTOCOL \
	      -s $PLUTO_PEER_CLIENT $S_PEER_PORT \
	      -d $PLUTO_MY_CLIENT $D_MY_PORT \
	         $IPSEC_POLICY_IN -j ACCEPT
	fi
	#
	# a virtual IP requires an INPUT and OUTPUT rule on the host
	# or sometimes host access via the internal IP is needed
	if [ -n "$PLUTO_MY_SOURCEIP" -o -n "$PLUTO_HOST_ACCESS" ]
	then
	  iptables -D INPUT -i $PLUTO_INTERFACE -p $PLUTO_MY_PROTOCOL \
	      -s $PLUTO_PEER_CLIENT $S_PEER_PORT \
	      -d $PLUTO_MY_CLIENT $D_MY_PORT \
	         $IPSEC_POLICY_IN -j ACCEPT
	  iptables -D OUTPUT -o $PLUTO_INTERFACE -p $PLUTO_PEER_PROTOCOL \
	      -s $PLUTO_MY_CLIENT $S_MY_PORT \
	      -d $PLUTO_PEER_CLIENT $D_PEER_PORT \
	         $IPSEC_POLICY_OUT -j ACCEPT
	fi
	#
	# IPIP exception teardown
	if [ -n "$PLUTO_IPCOMP" ]
	then
	  iptables -D INPUT -i $PLUTO_INTERFACE -p 4 \
	      -s $PLUTO_PEER -d $PLUTO_ME $IPSEC_POLICY_IN -j ACCEPT
	fi
	#
	# log IPsec client connection teardown
	if [ $VPN_LOGGING ]
	then
	  if [ "$PLUTO_PEER_CLIENT" = "$PLUTO_PEER/32" ]
	  then
	    logger -t $TAG -p $FAC_PRIO -- \
	      "- $PLUTO_PEER_ID $PLUTO_PEER -- $PLUTO_ME == $PLUTO_MY_CLIENT"
	  else
	    logger -t $TAG -p $FAC_PRIO -- \
	      "- $PLUTO_PEER_ID $PLUTO_PEER_CLIENT == $PLUTO_PEER -- $PLUTO_ME == $PLUTO_MY_CLIENT"
	  fi
	fi
	;;
*)	echo "$0: unknown verb \`$PLUTO_VERB' or parameter \`$1'" >&2
	exit 1
	;;
esac