#! /bin/sh
# iproute2 version, default updown script
#
# Copyright (C) 2003-2004 Nigel Metheringham
# Copyright (C) 2002-2007 Michael Richardson <mcr@xelerance.com>
# Copyright (C) 2003-2013 Tuomo Soini <tis@foobar.fi>
# Copyright (C) 2003-2007 Paul Wouters <paul@xelerance.com>
#
# 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 Libreswan 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
# Libreswan use yours instead of this default one.

test ${IPSEC_INIT_SCRIPT_DEBUG} && set -v -x

LC_ALL=C
export LC_ALL

# 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, prepare-client, up-host, up-client,
#		down-host, or down-client).  If the address family
#		for security gateway to security gateway communications
#		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_CONN_POLICY
#		the policy of the connection, as in:
#		RSASIG+ENCRYPT+TUNNEL+PFS+DONTREKEY+OPPORTUNISTIC
#		+failureDROP+lKOD+rKOD
#
#	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_METRIC
#		is the metric to set for the route
#
#	PLUTO_MTU
#		is the mtu to set for the route
#
#	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_MY_SOURCEIP
#		if non-empty, then the source address for the route will be
#		set to this IP address.
#
#	PLUTO_MY_PROTOCOL
#		is the protocol  for this  connection.  Useful  for
#		firewalling.
#
#	PLUTO_MY_PORT
#		is the port. Useful for firewalling.
#
#	PLUTO_PEER
#		is the IP address of our peer.
#
#	PLUTO_PEER_CLIENT
#		is the IP address / count of the peer's client subnet.
#		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_PROTOCOL
#		is  the  protocol  set  for  remote  end  with port
#		selector.
#
#	PLUTO_PEER_PORT
#		is the peer's port. Useful for firewalling.
#
#	PLUTO_CONNECTION_TYPE
#
#	PLUTO_CONN_ADDRFAMILY
#		is the family type, "ipv4" or "ipv6"
#
#	PLUTO_STACK
#		the kernel stack being used (eg protostack= value)
#
#	PLUTO_NM_CONFIGURED
#		is NetworkManager used for resolv.conf update
#
#       PLUTO_SA_REQID
#               When using KAME or XFRM/NETKEY, the IPsec SA reqid value

# Import default _updown configs from the
# @FINALSYSCONFDIR@/[sysconfig|default]/pluto_updown file
#
# Two variables can be set in this file:
#
#	IPROUTETABLE
#		is the default value for IPROUTETABLE
#
#	IPROUTEARGS
#		is the extra argument list for ip route command
#
#	IPRULEARGS
#		is the extra argument list for ip rule command

# rpm based systems
if [ -f @FINALSYSCONFDIR@/sysconfig/pluto_updown ]; then
    . @FINALSYSCONFDIR@/sysconfig/pluto_updown
# deb based systems
elif [ -f @FINALSYSCONFDIR@/default/pluto_updown ]; then
    . @FINALSYSCONFDIR@/default/pluto_updown
fi

LIBRESWAN_RESOLV_CONF=@FINALVARDIR@/run/pluto/libreswan-resolv-conf-backup
ORIG_RESOLV_CONF=@FINALSYSCONFDIR@/resolv.conf

# check parameter(s)
case "${1}:$*" in
    ':')
	# no parameters
	;;
    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
    ip route flush cache
}

downroute() {
    doroute delete
    ip route flush cache
}

uprule() {
    # policy based advanced routing
    if [ -n "${IPROUTETABLE}" ]; then
	dorule delete
	dorule add
    fi
    # virtual sourceip support
    if [ -n "${PLUTO_MY_SOURCEIP}" ]; then
	addsource
	changesource
    fi
    ip route flush cache
}

downrule() {
    if [ -n "${PLUTO_MY_SOURCEIP}"  -a ${PLUTO_IS_PEER_CISCO} -eq 1 ]; then
	dorule delete
	ip route flush cache
    fi
}

updateresolvconf() {
	if [ -z "${PLUTO_PEER_DNS_INFO}" -o -z "${PLUTO_PEER_DOMAIN_INFO}" ]; then
		return 0
	fi

	if [ -n "$(pidof unbound)" ]; then
	    echo "updating local nameserver for ${PLUTO_PEER_DOMAIN_INFO} with ${PLUTO_PEER_DNS_INFO}"
	    /usr/sbin/unbound-control forward_add ${PLUTO_PEER_DOMAIN_INFO} ${PLUTO_PEER_DNS_INFO}
	    /usr/sbin/unbound-control flush_zone ${PLUTO_PEER_DOMAIN_INFO}
	    /usr/sbin/unbound-control flush_requestlist
	    return 0
	fi

	if [ -z "${PLUTO_NM_CONFIGURED}" -o "${PLUTO_NM_CONFIGURED}" = 0 ]; then
		echo "updating resolvconf"

		if [ ! -e "${ORIG_RESOLV_CONF}" ]; then
			echo "resolv.conf does not exist, so doing nothing"
			return 0
		fi

		if [ -e "${LIBRESWAN_RESOLV_CONF}" ]; then
			if grep 'Libreswan' ${ORIG_RESOLV_CONF} > /dev/null 2>&1; then
				echo "Current resolv.conf is generated by Libreswan, and backup resolv.conf already exists, so doing nothing"
				return 0
			else
				echo "backup resolv.conf exists, but current resolv.conf is not generated by Libreswan"
			fi
		fi

		rm -f ${LIBRESWAN_RESOLV_CONF}
		cp -- ${ORIG_RESOLV_CONF} ${LIBRESWAN_RESOLV_CONF}

		RESOLVE_CONF="# Generated by Libreswan (IPSec)"

		if [ -n "${PLUTO_PEER_DOMAIN_INFO}" ]; then
			if grep 'domain' ${ORIG_RESOLV_CONF} > /dev/null 2>&1; then
				RESOLVE_CONF="${RESOLVE_CONF}\ndomain ${PLUTO_PEER_DOMAIN_INFO}\nsearch ${PLUTO_PEER_DOMAIN_INFO}"
			else
				RESOLVE_CONF="${RESOLVE_CONF}\nsearch ${PLUTO_PEER_DOMAIN_INFO}"
			fi
		fi

		if [ -n "${PLUTO_PEER_DNS_INFO}" ]; then
			for i in ${PLUTO_PEER_DNS_INFO}; do
				RESOLVE_CONF="${RESOLVE_CONF}\nnameserver $i"
			done
		fi

		ORIG_NAMESERVER=$(grep -m 1 ^nameserver ${ORIG_RESOLV_CONF})
		RESOLVE_CONF="${RESOLVE_CONF}\n${ORIG_NAMESERVER}\n"

		rm -f -- ${ORIG_RESOLV_CONF}
		printf "${RESOLVE_CONF}" > ${ORIG_RESOLV_CONF}
		return $?

	else
		echo "Updating resolv.conf is controlled by Network Manager"
		libreswan_reason=connect
		export libreswan_reason
		export PLUTO_PEER_DOMAIN_INFO
		export PLUTO_PEER_DNS_INFO
		export PLUTO_PEER_BANNER
		export PLUTO_MY_SOURCEIP
		export PLUTO_PEER
		/usr/libexec/nm-libreswan-service-helper
		return 0
	fi
}

restoreresolvconf() {
	if [ -z "${PLUTO_PEER_DNS_INFO}" -o -z "${PLUTO_PEER_DOMAIN_INFO}" ]; then
		return 0
	fi

	if [ -n "$(pidof unbound)" ]; then
		echo "flushing local nameserver of ${PLUTO_PEER_DOMAIN_INFO}"
		/usr/sbin/unbound-control forward_remove ${PLUTO_PEER_DOMAIN_INFO}
		/usr/sbin/unbound-control flush_zone ${PLUTO_PEER_DOMAIN_INFO}
		/usr/sbin/unbound-control flush_requestlist
		return 0
	fi

	if [ -z "${PLUTO_NM_CONFIGURED}" -o "${PLUTO_NM_CONFIGURED}" = 0 ]; then
		echo "restoring resolvconf"
		if [ ! -e "${LIBRESWAN_RESOLV_CONF}" ]; then
			echo "Problem in restoring the resolv.conf, as there is no backup file"
			return 2
		fi

		if grep 'Libreswan' ${ORIG_RESOLV_CONF} > /dev/null 2>&1; then
			cp -- "${LIBRESWAN_RESOLV_CONF}" ${ORIG_RESOLV_CONF}
		else
			echo "Current resolv.conf is not generated by Libreswan, so doing nothing"
		fi

		rm -f -- "${LIBRESWAN_RESOLV_CONF}"
		return 0
	else
		# Here disconnect signal is sent to NetworkManager
		# whenever an already established connection is being terminated.
		unset libreswan_reason
		unset PLUTO_PEER_DOMAIN_INFO
		unset PLUTO_PEER_DNS_INFO
		unset PLUTO_PEER_BANNER
		unset PLUTO_MY_SOURCEIP
		unset PLUTO_PEER
		echo "Restoring resolv.conf is controlled by Network Manager"
		disconnectNM
	fi
}

disconnectNM() {
    # This will be called whenever a connection fails to establish
    # due to a state (either phase 1, xauth phase, or phase 2) fails.
    # This will send a singal to NetworkManager over dbus so that NM
    # can clear up coonnections.
    libreswan_reason=disconnect
    export libreswan_reason
    echo "sending disconnect signal to NetworkManager"
    /usr/libexec/nm-libreswan-service-helper
    return 0
 }

addsource() {
    st=0
    # check if given sourceip is local and add as alias if not
    if ! ip -o route get ${PLUTO_MY_SOURCEIP%/*} | grep -q ^local; then
	it="ip addr add ${PLUTO_MY_SOURCEIP%/*}/32 dev ${PLUTO_INTERFACE%:*}"
	oops="$(eval ${it} 2>&1)"
	st=$?
	if [ -z "${oops}" -a ${st} -ne 0 ]; then
	    oops="silent error, exit status ${st}"
	fi
	case "${oops}" in
	    'RTNETLINK answers: File exists'*)
		# should not happen, but ... ignore if the
		# address was already assigned on interface
		oops=""
		st=0
		;;
	esac
	if [ -n "${oops}" -o ${st} -ne 0 ]; then
	    echo "${0}: addsource \"${it}\" failed (${oops})" >&2
	fi
    fi
    return ${st}
}

changesource() {
    st=0
    parms="${PLUTO_PEER_CLIENT}"
    parms2="dev ${PLUTO_INTERFACE}"
    parms3="src ${PLUTO_MY_SOURCEIP%/*}"
    if [ -n "${IPROUTETABLE}" ]; then
	parms3="${parms3} table ${IPROUTETABLE}"
    fi
    it="ip route replace ${parms} ${parms2} ${parms3}"
    case "${PLUTO_PEER_CLIENT}" in
 	"0.0.0.0/0"|"::/0")
	    # opportunistic encryption work around
	    it=
 	    ;;
    esac
    oops="$(eval ${it} 2>&1)"
    st=$?
    if [ -z "${oops}" -a ${st} -ne 0 ]; then
	oops="silent error, exit status ${st}"
    fi
    if [ -n "${oops}" -o ${st} -ne 0 ]; then
	echo "${0}: changesource \"${it}\" failed (${oops})" >&2
    fi
    return ${st}
}

dorule() {
    st=0
    it2=
    iprule="from ${PLUTO_MY_CLIENT}"
    iprule2="to ${PLUTO_PEER_CLIENT}"
    if [ -n "${IPROUTETABLE}" ]; then
	iprule2="${iprule2} table ${IPROUTETABLE}"
    fi
    iprule2="${iprule2} ${IPRULEARGS}"

    case "${PLUTO_PEER_CLIENT}" in
	"0.0.0.0/0"|"::/0")
	    # opportunistic encryption work around
	    st=0
	    ;;
	*)
	    if [ -z "${PLUTO_MY_SOURCEIP}" ]; then
		if [ "${PLUTO_ME}" = "${PLUTO_MY_CLIENT%/*}" ]; then
		    it="ip rule ${1} iif lo ${iprule2}"
		else
		    it="ip rule ${1} ${iprule} ${iprule2}"
		fi
	    else
		if [ "${PLUTO_MY_SOURCEIP%/*}" = "${PLUTO_MY_CLIENT%/*}" ]; then
		    it="ip rule ${1} iif lo ${iprule2}"
		else
		    it="ip rule ${1} ${iprule} ${iprule2}"
		    it2="ip rule ${1} iif lo ${iprule2}"
		fi
	    fi
	    oops="$(eval ${it} 2>&1)"
	    st=$?
	    if [ -z "${oops}" -a ${st} -ne 0 ]; then
		oops="silent error, exit status ${st}"
	    fi
	    case "${oops}" in
		'RTNETLINK answers: No such process'*)
		    # This is what ip rule gives
		    # for "could not find such a rule"
		    oops=
		    st=0
		    ;;
	    esac
	    if [ -n "${oops}" -o ${st} -ne 0 ]; then
		echo "${0}: dorule \"${it}\" failed (${oops})" >&2
	    fi
	    if [ ${st} -eq 0 -a -n "${it2}" ]; then
		oops="$(eval ${it2} 2>&1)"
		st=$?
		if [ -z "${oops}" -a ${st} -ne 0 ]; then
		    oops="silent error, exit status ${st}"
		fi
		case "${oops}" in
		    'RTNETLINK answers: No such process'*)
			# This is what ip rule gives
			# for "could not find such a rule"
			oops=
			st=0
			;;
		esac
		if [ -n "${oops}" -o ${st} -ne 0 ]; then
		    echo "${0}: dorule \"${it2}\" failed (${oops})" >&2
		fi
	    fi
	    ;;
    esac
    return ${st}
}


doroute() {
    st=0
    parms="${PLUTO_PEER_CLIENT}"
    parms2=

    if [ -n "${PLUTO_NEXT_HOP}" -a "${PLUTO_NEXT_HOP}" != "${PLUTO_PEER}" ]; then
	# nexthop is not needed on ppp interfaces. unset it to make cases
	# work, where left is set but no leftnexthop (e.g. left=%dynamic)
	ip link show "${PLUTO_INTERFACE}" | grep -qs POINTOPOINT && unset PLUTO_NEXT_HOP

	# skip routing via nexthop if it is not reachable through any
	# directly connected network (but via default route only):
	ip route list match "${PLUTO_NEXT_HOP}" dev "${PLUTO_INTERFACE}" | \
	    grep -qs -v default || unset PLUTO_NEXT_HOP

	if [ -n "${PLUTO_NEXT_HOP}" ]; then
	    parms2="via ${PLUTO_NEXT_HOP}"
	fi
    fi

    parms2="${parms2} dev ${PLUTO_INTERFACE}${PLUTO_MTU:+ mtu ${PLUTO_MTU}}${PLUTO_METRIC:+ metric ${PLUTO_METRIC}}"
    parms3="${IPROUTEARGS}"
    if [ -n "${IPROUTETABLE}" ]; then
	parms3="${parms3} table ${IPROUTETABLE}"
    fi

    if [ "${1}" = "add" -a -n "${PLUTO_MY_SOURCEIP}" ]; then
	addsource
	parms3="${parms3} src ${PLUTO_MY_SOURCEIP%/*}"
    fi

    case "${PLUTO_PEER_CLIENT}" in
	"0.0.0.0/0")
	    # opportunistic encryption work around
	    # need to provide route that eclipses default, without
	    # replacing it.
	    it="ip route ${1} 0.0.0.0/1 ${parms2} ${parms3} &&
		ip route ${1} 128.0.0.0/1 ${parms2} ${parms3}"
	    ;;
	"::/0")
	    # opportunistic encryption work around
	    # need to provide route that eclipses default, without
	    # replacing it.
	    it="ip -6 route ${1} 0::/1 ${parms2} ${parms3} &&
		ip -6 route ${1} 8000::/1 ${parms2} ${parms3}"
	    ;;

	*)
	    # Despite not having -6, the ip route commands works for ipv6
	    it="ip route ${1} ${parms} ${parms2} ${parms3}"
	    ;;
    esac
    oops="$(eval ${it} 2>&1)"
    st=$?
    if [ -z "${oops}" -a ${st} -ne 0 ]; then
	oops="silent error, exit status ${st}"
    fi
    case "${oops}" in
	'RTNETLINK answers: No such process'*)
	    # should not happen, but ... ignore if the
	    # route was already removed
	    oops=""
	    st=0
	    ;;
    esac
    if [ -n "${oops}" -o ${st} -ne 0 ]; then
	echo "${0}: doroute \"${it}\" failed (${oops})" >&2
    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}" in
	    "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 delete ${parms1} ${IPROUTEARGS} 2>&1 ; ip route delete ${parms2} ${IPROUTEARGS} 2>&1"
		oops="$(ip route delete ${parms1} ${IPROUTEARGS} 2>&1 ; ip route delete ${parms2} ${IPROUTEARGS} 2>&1)"
		;;
	    "::/0")
		# need to provide route that eclipses default, without
		# replacing it.
		parms1="0::/1"
		parms2="8000::/1"
		it="ip route delete ${parms1} ${IPROUTEARGS} 2>&1 ; ip route delete ${parms2} ${IPROUTEARGS} 2>&1"
		oops="$(ip route delete ${parms1} ${IPROUTEARGS} 2>&1 ; ip route delete ${parms2} ${IPROUTEARGS} 2>&1)"
		;;
	    *)
		parms="${PLUTO_PEER_CLIENT} ${IPROUTEARGS}"
		if [ -n "${IPROUTETABLE}" ]; then
		    parms="${parms} table ${IPROUTETABLE}"
		fi
		it="ip route delete ${parms} 2>&1"
		oops="$(ip route delete ${parms} 2>&1)"
		;;
	esac
	st="$?"
	if [ -z "${oops}" -a ${st} -ne 0 ]; then
	    oops="silent error, exit status ${st}"
	fi
	case "${oops}" in
	    *'RTNETLINK answers: No such process'*)
		# This is what route (currently -- not documented!) gives
		# for "could not find such a route".
		oops=
		st=0
		;;
	esac
	if [ -n "${oops}" -o ${st} -ne 0 ]; then
	    echo "${0}: \"${it}\" failed (${oops})" >&2
	fi
	exit ${st}
	;;
    route-host:*|route-client:*)
	# connection to me or my client subnet being routed
	uproute
	;;
    unroute-host:*|unroute-client:*)
	# connection to me or my client subnet being unrouted
	downroute
	;;
    up-host:*)
	# connection to me coming up
	uprule
	# If you are doing a custom version, firewall commands go here.
	;;
    down-host:*)
	# connection to me going down
	downrule
	# If you are doing a custom version, firewall commands go here.
	;;
    up-client:)
	# connection to my client subnet coming up
	uprule
	# If you are doing a custom version, firewall commands go here.
	updateresolvconf
	;;
    down-client:)
	# connection to my client subnet going down
	downrule
	# If you are doing a custom version, firewall commands go here.
	restoreresolvconf
	;;
    disconnectNM-host|disconnectNM-client)
	# sending disconnect signal to NM, as something went wrong.
	disconnectNM
	;;
    #
    # IPv6
    #
    prepare-host-v6:*|prepare-client-v6:*)
	case "${PLUTO_PEER_CLIENT_NET}" in
	    "0.0.0.0"|"::/0"|"%any")
		;;
	    *)
		ip -6 route del ${PLUTO_PEER_CLIENT} || echo
		;;
	esac
	;;
    route-host-v6:*|route-client-v6:*)
	# connection to me or my client subnet being routed
	uproute
	#uproute_v6
	;;
    unroute-host-v6:*|unroute-client-v6:*)
	# connection to me or my client subnet being unrouted
	downroute
	#downroute_v6
	;;
    up-host-v6:*)
	# connection to me coming up
	uprule
	# If you are doing a custom version, firewall commands go here.
	;;
    down-host-v6:*)
	# connection to me going down
	downrule
	# If you are doing a custom version, firewall commands go here.
	;;
    up-client-v6:)
	# connection to my client subnet coming up
	uprule
	# If you are doing a custom version, firewall commands go here.
	;;
    down-client-v6:)
	# connection to my client subnet going down
	downrule
	# If you are doing a custom version, firewall commands go here.
	;;
    *)
	echo "${0}: unknown verb \"${PLUTO_VERB}\" or parameter \"${1}\"" >&2
	exit 1
	;;
esac