#!/bin/sh
#
# Shorewall 3.2 -- /usr/share/shorewall/functions
#
#     This program is under GPL [http://www.gnu.org/copyleft/gpl.htm]
#
#     (c) 1999,2000,2001,2002,2003,2004,2005,2006 - Tom Eastep (teastep@shorewall.net)
#
#	Complete documentation is available at http://shorewall.net
#
#	This program is free software; you can redistribute it and/or modify
#	it under the terms of Version 2 of the GNU General Public License
#	as published by the Free Software Foundation.
#
#	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.
#
#	You should have received a copy of the GNU General Public License
#	along with this program; if not, write to the Free Software
#	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA

LIBVERSION=30200

[ -n "${VARDIR:=/var/lib/shorewall}" ]
[ -n "${SHAREDIR:=/usr/share/shorewall}" ]
[ -n "${CONFDIR:=/etc/shorewall}" ]

#
# Message to stderr
#
error_message() # $* = Error Message
{
   echo "   $@" >&2
}

# Function to truncate a string -- It uses 'cut -b -<n>'
# rather than ${v:first:last} because light-weight shells like ash and
# dash do not support that form of expansion.
#

truncate() # $1 = length
{
    cut -b -${1}
}

#
# Split a colon-separated list into a space-separated list
#
split() {
    local ifs=$IFS
    IFS=:
    set -- $1
    echo $*
    IFS=$ifs
}

#
# Search a list looking for a match -- returns zero if a match found
# 1 otherwise
#
list_search() # $1 = element to search for , $2-$n = list
{
    local e=$1

    while [ $# -gt 1 ]; do
	shift
	[ "x$e" = "x$1" ] && return 0
    done

    return 1
}

#
# Return a space separated list of values matching
#
list_walk() # $1 = element to search for, $2-$n = list
{
    local e=$1 result=

    while [ $# -gt 1 ]; do
	shift
	case $1 in
	    $e*)
	    	result="$result ${1##$e}"
		;;
	esac
    done
    echo $result
}

#
# Functions to count list elements
# - - - - - - - - - - - - - - - -
# Whitespace-separated list
#
list_count1() {
    echo $#
}
#
# Comma-separated list
#
list_count() {
    list_count1 $(separate_list $1)
}

#
# Conditionally produce message
#
progress_message() # $* = Message
{
    local timestamp=

    if [ $VERBOSE -gt 1 ]; then
	[ -n "$TIMESTAMP" ] && timestamp="$(date +%H:%M:%S) "
	echo "${timestamp}$@"
    fi
}

progress_message2() # $* = Message
{
    local timestamp=

    if [ $VERBOSE -gt 0 ]; then
	[ -n "$TIMESTAMP" ] && timestamp="$(date +%H:%M:%S) "
	echo "${timestamp}$@"
    fi
}

progress_message3() # $* = Message
{
    local timestamp=

    if [ $VERBOSE -ge 0 ]; then
	[ -n "$TIMESTAMP" ] && timestamp="$(date +%H:%M:%S) "
	echo "${timestamp}$@"
    fi
}

#
# Suppress all output for a command
#
qt()
{
    "$@" >/dev/null 2>&1
}

#
# Determine if Shorewall is "running"
#
shorewall_is_started() {
    qt $IPTABLES -L shorewall -n
}

#
# Perform variable substitution on the passed argument and echo the result
#
expand() # $@ = contents of variable which may be the name of another variable
{
    eval echo \"$@\"
}

#
# Perform variable substitition on the values of the passed list of variables
#
expandv() # $* = list of variable names
{
    local varval

    while [ $# -gt 0 ]; do
	eval varval=\$${1}
	eval $1=\"$varval\"
	shift
    done
}

#
# Add whitespace after "!"
#
fix_bang()
{
    local result=

    while [ $# -gt 0 ]; do
	case $1 in
	    !*)
		result="$result ! ${1#!}"
		;;
	    *)
		result="$result $1"
		;;
	esac
	shift
    done

    echo $result
}

#
# Echos the fully-qualified name of the calling shell program
#
my_pathname() {
    cd $(dirname $0)
    echo $PWD/$(basename $0)
}

#
# Set default config path
#
ensure_config_path() {
    local F=${SHAREDIR}/configpath
    if [ -z "$CONFIG_PATH" ]; then
	[ -f $F ] || { echo "   ERROR: $F does not exist"; exit 2; }
	. $F
    fi
}

#
# Find a File -- For relative file name, look first in $SHOREWALL_DIR then in ${CONFDIR}
#
find_file()
{
    local saveifs= directory

    case $1 in
	/*)
	    echo $1
	    ;;
	*)
	    if [ -n "$SHOREWALL_DIR" -a -f $SHOREWALL_DIR/$1 ]; then
		echo $SHOREWALL_DIR/$1
	    else
		saveifs=$IFS
		IFS=:
		for directory in $CONFIG_PATH; do
		    if [ -f $directory/$1 ]; then
			echo $directory/$1
			IFS=$saveifs
			return
		    fi
		done

		IFS=$saveifs

		echo ${CONFDIR}/$1
	    fi
	    ;;
    esac
}

#
# Get fully-qualified name of file
#
resolve_file() # $1 = file name
{
    local pwd=$PWD

    case $1 in
	/*)
	    echo $1
	    ;;
	./*)
	    echo ${pwd}${1#.}
	    ;;
	../*)
	    cd ..
	    resolve_file ${1#../}
	    cd $pwd
	    ;;
	*)
	    echo $pwd/$1
	    ;;
    esac
}

##
# Source a user exit file if it exists
#
run_user_exit() # $1 = file name
{
    local user_exit=$(find_file $1)

    if [ -f $user_exit ]; then
	progress_message "Processing $user_exit ..."
	. $user_exit
    fi
}

#
# Replace commas with spaces and echo the result
#
separate_list() {
    local list="$@"
    local part
    local newlist
    local firstpart
    local lastpart
    local enclosure

    case "$list" in
	*,|,*|*,,*|*[[:space:]]*)
	    #
	    # There's been whining about us not catching embedded white space in
	    # comma-separated lists. This is an attempt to snag some of the cases.
	    #
	    # The 'TERMINATOR' function will be set by the 'firewall' script to
	    # either 'startup_error' or 'fatal_error' depending on the command and
	    # command phase
	    #
            [ -n "$TERMINATOR" ] && \
		$TERMINATOR "Invalid comma-separated list \"$@\""
            echo "WARNING -- invalid comma-separated list \"$@\"" >&2
	    ;;
	*\[*\]*)
	    #
	    # Where we need to embed comma-separated lists within lists, we enclose them
	    # within square brackets.
	    #
	    firstpart=${list%%\[*}
	    lastpart=${list#*\[}
	    enclosure=${lastpart%%\]*}
	    lastpart=${lastpart#*\]}
	    case $lastpart in
		\,*)
		    case $firstpart in
			*\,)
			    echo "$(separate_list ${firstpart%,}) [$enclosure] $(separate_list ${lastpart#,})"
			    ;;
			*)
			    echo "$(separate_list $firstpart)[$enclosure] $(separate_list ${lastpart#,})"
			    ;;
		    esac
		    ;;
		*)
		    case $firstpart in
			*\,)
			    echo "$(separate_list ${firstpart%,}) [$enclosure]$(separate_list $lastpart)"
			    ;;
			*)
			    echo "$(separate_list $firstpart)[$enclosure]$(separate_list $lastpart)"
			    ;;
		    esac
		    ;;
	    esac
	    return
	    ;;
    esac

    list="$@"
    part="${list%%,*}"
    newlist="$part"

    while [ "x$part" != "x$list" ]; do
	list="${list#*,}";
	part="${list%%,*}";
	newlist="$newlist $part";
    done

    echo "$newlist"
}

#
# Undo the effect of 'separate_list()'
#
combine_list()
{ 
    local f o=

    for f in $* ; do 
        o="${o:+$o,}$f"
    done
 
    echo $o
}

#
# Determine if a chain is a policy chain
#
is_policy_chain() # $1 = name of chain
{
    eval test \"\$${1}_is_policy\" = Yes
}

#
# Set a standard chain's policy
#
setpolicy() # $1 = name of chain, $2 = policy
{
    run_iptables -P $1 $2
}

#
# Set a standard chain to enable established and related connections
#
setcontinue() # $1 = name of chain
{
    run_iptables -A $1 -m state --state ESTABLISHED,RELATED -j ACCEPT
}

#
# Flush one of the NAT table chains
#
flushnat() # $1 = name of chain
{
    run_iptables -t nat -F $1
}

#
# Flush one of the Mangle table chains
#
flushmangle() # $1 = name of chain
{
    run_iptables -t mangle -F $1
}

#
# This function assumes that the TMP_DIR variable is set and that
# its value names an existing directory.
#
determine_zones()
{
    local zone parent parents rest new_zone_file= r

    merge_zone()
    {
	local z zones="$ZONES" merged=

	if [ -n "$parents" ]; then
	    ZONES=
	    for z in $zones; do
		if [ -z "$merged" ] && list_search $z $parents; then
		    ZONES="$ZONES $zone"
		    merged=Yes
		fi
		ZONES="$ZONES $z"
	    done
	else
	    ZONES="$ZONES $zone"
	fi
    }

    strip_file zones

    ZONES=
    IPV4_ZONES=
    IPSEC_ZONES=

    [ "$IPSECFILE" = zones ] && new_zone_file=Yes || test -n "${FW:=fw}"

    while read zone type rest; do
	expandv zone type

	case $zone in
	    *:*)
		parents=${zone#*:}
		zone=${zone%:*}
		[ -n "$zone" ] || startup_error "Invalid nested zone syntax: :$parents"
		parents=$(separate_list $parents)
		eval ${zone}_parents=\"$parents\"
		;;
	    *)
		parents=
		eval ${zone}_parents=
		;;
	esac

	for parent in $parents; do
	    [ "$parent" = "$FW" ] && startup_error "Sub-zones of the firewall zone are not allowed"
	    list_search $parent $ZONES || startup_error "Parent zone not defined: $parent"
	done

	[ ${#zone} -gt 5 ] && startup_error "Zone name longer than 5 characters: $zone"

	case "$zone" in
	    [0-9*])
                startup_error "Illegal zone name \"$zone\" in zones file"
		;;
            all|none)
	        startup_error "Reserved zone name \"$zone\" in zones file"
		;;
        esac

	if [ -n "$new_zone_file" ]; then
	    case ${type:=ipv4} in
		ipv4|IPv4|IPV4|plain|-)
		    list_search $zone $ZONES $FW && startup_error "Zone $zone is defined more than once"
		    merge_zone
		    IPV4_ZONES="$IPV4_ZONES $zone"
		    ;;
		ipsec|IPSEC|ipsec4|IPSEC4)
		    list_search $zone $ZONES $FW && startup_error "Zone $zone is defined more than once"
		    [ -n "$POLICY_MATCH" ] || startup_error "Your kernel and/or iptables does not support policy match"
		    eval ${zone}_is_ipsec=Yes
		    eval ${zone}_is_complex=Yes
		    merge_zone
		    IPSEC_ZONES="$IPSEC_ZONES $zone"
		    ;;
		firewall)
		    [ -n "$FW" ] && startup_error "Only one firewall zone may be defined"
		    list_search $zone $ZONES && startup_error "Zone $zone is defined more than once"
		    [ -n "$parents" ] && startup_error "The firewall zone may not be nested"
		    for r in $rest; do
			[ "x$r" = x- ] || startup_error "OPTIONS not allowed on the firewall zone"
		    done
		    FW=$zone
		    ;;
		*)
		    startup_error "Invalid Zone Type: $type"
		    ;;
	    esac

	    eval ${zone}_type=$type
	else
	    list_search $zone $ZONES $FW && startup_error "Zone $zone is defined more than once"
	    ZONES="$ZONES $zone"
	    IPV4_ZONES="$IPV4_ZONES $zone"
	    eval ${zone}_type=ipv4
	fi
    done < $TMP_DIR/zones

    [ -z "$ZONES" ] && startup_error "No ipv4 or ipsec Zones Defined"

    [ -z "$FW" ] && startup_error "No Firewall Zone Defined"
}

#
# Validate the zone names and options in the interfaces file
#
validate_interfaces_file() {
    local wildcard
    local found_obsolete_option=
    local z interface networks options r iface option

    while read z interface networks options; do
	expandv z interface networks options
	r="$z $interface $networks $options"

	[ "x$z" = "x-" ] && z=

	if [ -n "$z" ]; then
	    validate_zone $z || startup_error "Invalid zone ($z) in record \"$r\""
	fi

	list_search $interface $ALL_INTERFACES && \
	    startup_error "Duplicate Interface $interface"

	wildcard=

	case $interface in
	    *:*|+)
		startup_error "Invalid Interface Name: $interface"
		;;
	    *+)
		wildcard=Yes
		;;
	esac

	ALL_INTERFACES="$ALL_INTERFACES $interface"
	options=$(separate_list $options)
	iface=$(chain_base $interface)

	eval ${iface}_broadcast="$networks"
	eval ${iface}_zone="$z"
	eval ${iface}_options=\"$options\"

	for option in $options; do
	    case $option in
		-)
		    ;;
		dhcp|tcpflags|arp_filter|routefilter|logmartians|sourceroute|blacklist|proxyarp|nosmurfs|upnp|-)
		    ;;
		maclist)
		    lib_load maclist "The 'maclist' option"
		    ;;
		norfc1918)
		    if [ "$PROGRAM" = compiler ]; then
			indent >&3 << __EOF__
addr=\$(ip -f inet addr show $interface 2> /dev/null | grep 'inet\ ' | head -n1)
if [ -n "\$addr" ]; then
    addr=\$(echo \$addr | sed 's/inet //;s/\/.*//;s/ peer.*//')
    for network in 10.0.0.0/8 176.16.0.0/12 192.168.0.0/16; do
        if in_network \$addr \$network; then
            startup_error "The 'norfc1918' option has been specified on an interface with an RFC 1918 address. Interface:$interface"
        fi
    done
fi
__EOF__
		    else
			addr=$(ip -f inet addr show $interface 2> /dev/null | grep inet | head -n1)
			if [ -n "$addr" ]; then
			    addr=$(echo $addr | sed 's/inet //;s/\/.*//;s/ peer.*//')
			    for network in 10.0.0.0/8 176.16.0.0/12 192.168.0.0/16; do
				if in_network $addr $network; then
				    startup_error "The 'norfc1918' option may not be specified on an interface with an RFC 1918 address. Interface:$interface"
				fi
			    done
			fi
		    fi
		    ;;
		arp_ignore=*)
		    eval ${iface}_arp_ignore=${option#*=}
		    ;;
		arp_ignore)
		    eval ${iface}_arp_ignore=1
		    ;;
		detectnets)
		    [ -n "$wildcard" ] && \
			startup_error "The \"detectnets\" option may not be used with a wild-card interface"
		    [ -n "$EXPORT" ] && \
			startup_error "'detectnets' not permitted with the -e run-line option"
		    ;;
		routeback)
		    [ -n "$z" ] || startup_error "The routeback option may not be specified on a multi-zone interface"
		    ;;
		*)
		    error_message "WARNING: Invalid option ($option) in record \"$r\""
		    ;;
	    esac
	done
    done < $TMP_DIR/interfaces

    [ -z "$ALL_INTERFACES" ] && startup_error "No Interfaces Defined"
}

#
# Process the ipsec information in the zones file
#
setup_ipsec() {
    local zone using_ipsec=
    #
    # Add a --set-mss rule to the passed chain
    #
    set_mss1() # $1 = chain, $2 = MSS
    {
	eval local policy=\$${1}_policy

	if [ "$policy" != NONE ]; then
	    ensurechain $1
	    run_iptables -I $1 -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --set-mss $2
	fi
    }
    #
    # Set up rules to set MSS to and/or from zone "$zone"
    #
    set_mss() # $1 = MSS value, $2 = _in, _out or ""
    {	
	for z in $ZONES $FW; do
	    case $2 in
		_in)
		    set_mss1 ${zone}2${z} $1
		    ;;
		_out)
		    set_mss1 ${z}2${zone} $1
		    ;;
		*)
		    set_mss1 ${z}2${zone} $1
		    set_mss1 ${zone}2${z} $1
		    ;;
	    esac
	done
    }

    do_options() # $1 = _in, _out or "" - $2 = option list
    {
	local option newoptions= val

	[ x${2} = x- ] && return

	for option in $(separate_list $2); do
	    val=${option#*=}

	    case $option in
		mss=[0-9]*)    [ "$PROGRAM" = compiler ] && set_mss $val $1 ;;
		strict)        newoptions="$newoptions --strict" ;;
		next)          newoptions="$newoptions --next" ;;
		reqid=*)       newoptions="$newoptions --reqid $val" ;;
		spi=*)         newoptions="$newoptions --spi $val" ;;
		proto=*)       newoptions="$newoptions --proto $val" ;;
		mode=*)        newoptions="$newoptions --mode $val" ;;
		tunnel-src=*)  newoptions="$newoptions --tunnel-src $val" ;;
		tunnel-dst=*)  newoptions="$newoptions --tunnel-dst $val" ;;
		reqid!=*)      newoptions="$newoptions ! --reqid $val" ;;
		spi!=*)        newoptions="$newoptions ! --spi $val" ;;
		proto!=*)      newoptions="$newoptions ! --proto $val" ;;
		mode!=*)       newoptions="$newoptions ! --mode $val" ;;
		tunnel-src!=*) newoptions="$newoptions ! --tunnel-src $val" ;;
		tunnel-dst!=*) newoptions="$newoptions ! --tunnel-dst $val" ;;
		*)             fatal_error "Invalid option \"$option\" for zone $zone" ;;
	    esac
	done

	if [ -n "$newoptions" ]; then
	    [ -n "$POLICY_MATCH" ] || fatal_error "Your kernel and/or iptables does not support policy match"
	    eval ${zone}_is_complex=Yes
	    eval ${zone}_ipsec${1}_options=\"${newoptions# }\"
	fi
    }

    case $IPSECFILE in
	zones)
	    f=zones
	    progress_message2 "$DOING IPSEC..."
	    ;;
	*)
	    f=$IPSECFILE
	    strip_file $f
	    progress_message2 "$DOING $f..."
	    using_ipsec=Yes
	    ;;
    esac

    while read zone type options in_options out_options mss; do
	expandv zone type options in_options out_options mss

	if [ -n "$using_ipsec" ]; then
	    validate_zone1 $zone || fatal_error "Unknown zone: $zone"
	fi

	if [ -n "$type" ]; then
	    if [ -n "$using_ipsec" ]; then
		case $type in
		    No|no)
			;;
		    Yes|yes)
			[ -n "$POLICY_MATCH" ] || fatal_error "Your kernel and/or iptables does not support policy match"
			eval ${zone}_is_ipsec=Yes
			eval ${zone}_is_complex=Yes
			eval ${zone}_type=ipsec4
			;;
		    *)
			fatal_error "Invalid IPSEC column contents"
			;;
		esac
	    fi

	    do_options ""     $options
	    do_options "_in"  $in_options
	    do_options "_out" $out_options
	fi

    done < $TMP_DIR/$f
}

#
# Validate the zone names and options in the hosts file
#
validate_hosts_file() {
   local z hosts options r interface host option zports

   check_bridge_port()
   {
       list_search ${interface}:${1} $zports || zports="$zports ${interface}:${1}"
       list_search $1 $ALL_PORTS || ALL_PORTS="$ALL_PORTS $1"
   }

   while read z hosts options; do
       expandv z hosts options
       r="$z $hosts $options"
       validate_zone1 $z || startup_error "Invalid zone ($z) in record \"$r\""

       case $hosts in
	   *:*)

	       interface=${hosts%%:*}
	       iface=$(chain_base $interface)

	       list_search  $interface $ALL_INTERFACES || \
		   startup_error "Unknown interface ($interface) in record \"$r\""

	       hosts=${hosts#*:}
	       ;;
	   *)
	       startup_error "Invalid HOST(S) column contents: $hosts"
	       ;;
       esac

       eval zports=\$${z}_ports

       for host in $(separate_list $hosts); do
	    if [ -n "$BRIDGING" ]; then
		case $host in
		   *:*)
		       known_interface ${host%:*} && \
			   startup_error "Bridged interfaces may not be defined in ${CONFDIR}/interfaces: $host"
		       check_bridge_port ${host%%:*}
		       ;;
		   *.*.*)
		       ;;
		   *+|+*)
		       eval ${z}_is_complex=Yes
		       ;;
		   *)
		       known_interface $host && \
			   startup_error "Bridged interfaces may not be defined in ${CONFDIR}/interfaces: $host"
		       check_bridge_port $host
		       ;;
	       esac
	   else
	       case $host in
		   *.*.*)
		       ;;
		   *+)
		       eval ${z}_is_complex=Yes
		       ;;
		   *)
		       startup_error "BRIDGING=Yes is needed for this zone definition: $r"
		       ;;
	       esac
	   fi

	   for option in $(separate_list $options) ; do
	       case $option in
		   norfc1918|blacklist|tcpflags|nosmurfs|-)
		       ;;
		   maclist)
		       	lib_load maclist "The 'maclist' option"
			;;
		   ipsec)
			[ -n "$POLICY_MATCH" ] || \
			    startup_error "Your kernel and/or iptables does not support policy match: ipsec"
			eval ${z}_ipsec_hosts=\"\$${z}_ipsec_hosts $interface:$host\"
			eval ${z}_is_complex=Yes
			;;
		   routeback)
			eval ${z}_routeback=\"$interface:$host \$${z}_routeback\"
			;;
		   *)
		       error_message "WARNING: Invalid option ($option) in record \"$r\""
		       ;;
	       esac
	   done
       done

       [ -n "$zports" ]  && eval ${z}_ports=\"$zports\"

   done < $TMP_DIR/hosts

   [ -n "$ALL_PORTS" ] && progress_message2 "   Bridge ports are: $ALL_PORTS"
}

#
# Find interfaces to a given zone
#
# Search the variables representing the contents of the interfaces file and
# for each record matching the passed ZONE, echo the expanded contents of
# the "INTERFACE" column
#
find_interfaces() # $1 = interface zone
{
    local zne=$1
    local z
    local interface

    for interface in $ALL_INTERFACES; do
	eval z=\$$(chain_base $interface)_zone
	[ "x${z}" = x${zne} ] && echo $interface
    done
}

#
# Forward Chain for an interface
#
forward_chain() # $1 = interface
{
   echo $(chain_base $1)_fwd
}

#
# Input Chain for an interface
#
input_chain() # $1 = interface
{
   echo $(chain_base $1)_in
}

#
# Output Chain for an interface
#
output_chain() # $1 = interface
{
   echo $(chain_base $1)_out
}

#
# Masquerade Chain for an interface
#
masq_chain() # $1 = interface
{
   echo $(chain_base $1)_masq
}

#
# MAC Verification Chain for an interface
#
mac_chain() # $1 = interface
{
   echo $(chain_base $1)_mac
}

macrecent_target() # $1 - interface
{
    [ -n "$MACLIST_TTL" ] && echo $(chain_base $1)_rec || echo RETURN
}

#
# Functions for creating dynamic zone rules
#
dynamic_fwd() # $1 = interface
{
   echo $(chain_base $1)_dynf
}

dynamic_in() # $1 = interface
{
   echo $(chain_base $1)_dyni
}

dynamic_out() # $1 = interface
{
   echo $(chain_base $1)_dyno
}

dynamic_chains() #$1 = interface
{
   local c=$(chain_base $1)

   echo ${c}_dyni ${c}_dynf ${c}_dyno
}

#
# DNAT Chain from a zone
#
dnat_chain() # $1 = zone
{
   echo ${1}_dnat
}

#
# SNAT Chain to an interface
#
snat_chain() # $1 = interface
{
   echo $(chain_base $1)_snat
}

#
# ECN Chain to an interface
#
ecn_chain() # $1 = interface
{
   echo $(chain_base $1)_ecn
}

#
# First chains for an interface
#
first_chains() #$1 = interface
{
   local c=$(chain_base $1)

   echo ${c}_fwd ${c}_in
}

#
# Horrible hack to work around an iptables limitation
#
iprange_echo()
{
    if [ -n "$KLUDGEFREE" ]; then
	echo "-m iprange $@"
    elif [ -f $TMP_DIR/iprange ]; then
	echo $@
    else
	echo "-m iprange $@"
	> $TMP_DIR/iprange
    fi
}

#
# Get set flags (ipsets).
#
get_set_flags() # $1 = set name and optional [levels], $2 = src or dst
{
    local temp setname=$1 options=$2

    [ -n "$IPSET_MATCH" ] || fatal_error "Your kernel and/or iptables does not include ipset match: $1"

    case $1 in
	*\[[1-6]\])
	    temp=${1#*\[}
	    temp=${temp%\]}
	    setname=${1%\[*}
	    while [ $temp -gt 1 ]; do
	       options="$options,$2"
	       temp=$(($temp - 1))
	    done
	    ;;
	*\[*\])
	    options=${1#*\[}
	    options=${options%\]}
	    setname=${1%\[*}
	    ;;
	*)
	    ;;
    esac

    echo "--set ${setname#+} $options"
}

#
# Horrible hack to work around an iptables limitation
#
physdev_echo()
{
    if [ -n "$KLUDGEFREE" ]; then
	echo -m physdev $@
    elif [ -f $TMP_DIR/physdev ]; then
	echo $@
    else
	echo -m physdev $@
	> $TMP_DIR/physdev
    fi
}

#
# We allow hosts to be specified by IP address or by physdev. These two functions
# are used to produce the proper match in a netfilter rule.
#
match_source_hosts()
{
    if [ -n "$BRIDGING" ]; then
	case $1 in
	    *:*)
		physdev_echo "--physdev-in ${1%:*} $(source_ip_range ${1#*:})"
		;;
	    *.*.*.*|+*|!+*)
		echo $(source_ip_range $1)
		;;
	    *)
		physdev_echo "--physdev-in $1"
		;;
	esac
    else
	echo $(source_ip_range $1)
    fi
}

match_dest_hosts()
{
    if [ -n "$BRIDGING" ]; then
	case $1 in
	    *:*)
		physdev_echo "--physdev-out ${1%:*} $(dest_ip_range ${1#*:})"
		;;
	    *.*.*.*|+*|!+*)
		echo $(dest_ip_range $1)
		;;
	    *)
		physdev_echo "--physdev-out $1"
		;;
	esac
    else
	echo $(dest_ip_range $1)
    fi
}

#
# Similarly, the source or destination in a rule can be qualified by a device name. If
# the device is defined in ${CONFDIR}/interfaces then a normal interface match is
# generated (-i or -o); otherwise, a physdev match is generated.
#-------------------------------------------------------------------------------------
#
# loosely match the passed interface with those in ${CONFDIR}/interfaces.
#
known_interface() # $1 = interface name
{
    local iface

    for iface in $ALL_INTERFACES ; do
	if if_match $iface $1 ; then
	    return 0
	fi
    done

    return 1
}

known_port() # $1 = port name
{
    local port

    for port in $ALL_PORTS ; do
	if if_match $port $1 ; then
	    return 0
	fi
    done

    return 1
}

match_source_dev()
{
    if [ -n "$BRIDGING" ]; then
	known_port $1 && physdev_echo "--physdev-in $1" || echo -i $1
    elif known_interface $1; then
	echo -i $1
    elif [ -n "$PHYSDEV_MATCH" ]; then
	physdev_echo "--physdev-in $1"
    else
	echo -i $1
    fi
}

match_dest_dev()
{
    if [ -n "$BRIDGING" ]; then
	known_port $1 && physdev_echo "--physdev-out $1" || echo -o $1
    elif known_interface $1; then
	echo -o $1
    elif [ -n "$PHYSDEV_MATCH" ]; then
	physdev_echo "--physdev-out $1"
    else
	echo -o $1
    fi
}

verify_interface()
{
    known_interface $1 || { [ -n "$BRIDGING" ] && known_port $1 ; }
}

#
# Determine if communication to/from a host is encrypted using IPSEC
#
is_ipsec_host() # $1 = zone, $2 = host
{
    eval local is_ipsec=\$${1}_is_ipsec
    eval local hosts=\"\$${1}_ipsec_hosts\"

    test -n "$is_ipsec" || list_search $2 $hosts
}

#
# Generate a match for decrypted packets
#
match_ipsec_in() # $1 = zone, $2 = host
{
    if is_ipsec_host $1 $2 ; then
	eval local options=\"\$${1}_ipsec_options \$${1}_ipsec_in_options\"
	echo "-m policy --pol ipsec --dir in $options"
    elif [ -n "$POLICY_MATCH" ]; then
	echo "-m policy --pol none --dir in"
    fi
}

#
# Generate a match for packets that will be encrypted
#
match_ipsec_out() # $1 = zone, $2 = host
{
    if is_ipsec_host $1 $2 ; then
	eval local options=\"\$${1}_ipsec_options \$${1}_ipsec_out_options\"
	echo "-m policy --pol ipsec --dir out $options"
    elif [ -n "$POLICY_MATCH" ]; then
	echo "-m policy --pol none --dir out"
    fi
}

#
# Jacket for ip_range() that takes care of iprange match
#

firewall_ip_range() # $1 = IP address or range
{
    [ -n "$IPRANGE_MATCH" ] && echo $1 || ip_range $1
}

#
#
# Find hosts in a given zone
#
# Read hosts file and for each record matching the passed ZONE,
# echo the expanded contents of the "HOST(S)" column
#
find_hosts() # $1 = host zone
{
    local hosts interface address addresses

    while read z hosts options; do
	if [ "x$(expand $z)" = "x$1" ]; then
	    expandv hosts
	    interface=${hosts%%:*}
	    addresses=${hosts#*:}
	    for address in $(separate_list $addresses); do
		echo $interface:$address
	    done
	fi
    done < $TMP_DIR/hosts
}

#
# Determine the interfaces on the firewall
#
# For each zone, create a variable called ${zone}_interfaces. This
# variable contains a space-separated list of interfaces to the zone
#
determine_interfaces() {
    for zone in $ZONES; do
	interfaces=$(find_interfaces $zone)
	interfaces=$(echo $interfaces) # Remove extra trash
	eval ${zone}_interfaces=\"\$interfaces\"
    done
}

#
# Determine if an interface has a given option
#
interface_has_option() # $1 = interface, #2 = option
{
    local options

    eval options=\$$(chain_base $1)_options

    list_search $2 $options
}

#
# Determine the defined hosts in each zone
#
determine_hosts() {
    for zone in $ZONES; do
	hosts=$(find_hosts $zone)
	hosts=$(echo $hosts) # Remove extra trash

	eval interfaces=\$${zone}_interfaces

	for interface in $interfaces; do
	    if interface_has_option $interface detectnets; then
		networks=$(get_routed_networks $interface "detectnets not allowed on interface with default route - $interface" )
	    else
		networks=0.0.0.0/0
	    fi

	    for network in $networks; do
		if [ -z "$hosts" ]; then
		    hosts=$interface:$network
		else
		    hosts="$hosts $interface:$network"
		fi

		if interface_has_option $interface routeback; then
		    eval ${zone}_routeback=\"$interface:$network \$${zone}_routeback\"
		fi
	    done
	done

	interfaces=

	for host in $hosts; do
	    interface=${host%:*}
	    if list_search $interface $interfaces; then
		list_search $interface:0.0.0.0/0 $hosts && \
		    startup_error "Invalid zone definition for zone $zone"
		list_search $interface:0/0 $hosts && \
		    startup_error "Invalid zone definition for zone $zone"
		eval ${zone}_is_complex=Yes
	    else
		if [ -z "$interfaces" ]; then
		    interfaces=$interface
		else
		    interfaces="$interfaces $interface"
		fi
	    fi
	done

	eval ${zone}_interfaces="\$interfaces"
	eval ${zone}_hosts="\$hosts"

	if [ -n "$hosts" ]; then
	    [ $VERBOSE -ge 1 ] && display_list "$zone Zone:" $hosts
	else
	    error_message "WARNING: Zone $zone is empty"
	fi
    done
}

#
# Ensure that the passed zone is defined in the zones file or is the firewall
#
validate_zone() # $1 = zone
{
    list_search $1 $ZONES $FW
}
#
# Ensure that the passed zone is defined in the zones file.
#
validate_zone1() # $1 = zone
{
    list_search $1 $ZONES
}

#
# Format a match by the passed MAC address
# The passed address begins with "~" and uses "-" as a separator between bytes
# Example: ~01-02-03-04-05-06
#
mac_match() # $1 = MAC address formated as described above
{
    echo "--match mac --mac-source $(echo $1 | sed 's/~//;s/-/:/g')"
}

#
# Find interfaces that have the passed option specified
#
find_interfaces_by_option() # $1 = option
{
    for interface in $ALL_INTERFACES; do
	eval options=\$$(chain_base $interface)_options
	list_search $1 $options && echo $interface
    done
}

#
# This slightly slower version is used to find both the option and option followed
# by equal sign ("=") and a value
#
find_interfaces_by_option1() # $1 = option
{
    local options option

    for interface in $ALL_INTERFACES; do
	eval options=\$$(chain_base $interface)_options
	for option in $options; do
	    if [ "${option%=*}" = "$1" ]; then
		echo $interface
		break
	    fi
	done
    done
}

#
# Find hosts with the passed option
#
find_hosts_by_option() # $1 = option
{
    local ignore hosts interface address addresses options ipsec= list

    while read ignore hosts options; do
	expandv options
	list=$(separate_list $options)
	if list_search $1 $list; then
	    list_search ipsec $list && ipsec=ipsec || ipsec=none
	    expandv hosts
	    interface=${hosts%%:*}
	    addresses=${hosts#*:}
	    for address in $(separate_list $addresses); do
		echo ${ipsec}^$interface:$address
	    done
	fi
    done < $TMP_DIR/hosts

    for interface in $ALL_INTERFACES; do
	interface_has_option $interface $1 && \
	    echo none^${interface}:0.0.0.0/0
    done
}

#
# Flush and delete all user-defined chains in the filter table
#
deleteallchains() {
    run_iptables -F
    run_iptables -X
}

#
# Process the routestopped file either adding or deleting rules
#
process_routestopped() # $1 = command
{
    local hosts= interface host host1 options networks source= dest= matched

    while read interface host options; do
	expandv interface host options
	[ "x$host" = "x-" -o -z "$host" ] && host=0.0.0.0/0
	for h in $(separate_list $host); do
	    hosts="$hosts $interface:$h"
	done

	routeback=

	if [ -n "$options" ]; then
	    for option in $(separate_list $options); do
		case $option in
		    routeback)
			if [ -n "$routeback" ]; then
			    error_message "WARNING: Duplicate routestopped option ignored: routeback"
			else
			    routeback=Yes
			    for h in $(separate_list $host); do
				run_iptables $1 FORWARD -i $interface -o $interface $(both_ip_ranges $h $h) -j ACCEPT
			    done
			fi
			;;
		    source)
			for h in $(separate_list $host); do
			    source="$source $interface:$h"
			done
			;;
		    dest)
			for h in $(separate_list $host); do
			    dest="$dest $interface:$h"
			done
			;;
		    critical)
			;;
		    *)
			error_message "WARNING: Unknown routestopped option ignored: $option"
			;;
		esac
	    done
	fi

    done < $TMP_DIR/routestopped


    for host in $hosts; do
	interface=${host%:*}
	networks=${host#*:}
	source_range=$(source_ip_range $networks)
	dest_range=$(dest_ip_range $networks)
	run_iptables $1 INPUT  -i $interface $source_range -j ACCEPT
	[ -z "$ADMINISABSENTMINDED" ] && \
	    run_iptables $1 OUTPUT -o $interface $dest_range -j ACCEPT

	matched=

	if list_search $host $source ; then
	    run_iptables $1 FORWARD -i $interface $source_range -j ACCEPT
	    matched=Yes
	fi

	if list_search $host $dest ; then
	    run_iptables $1 FORWARD -o $interface $dest_range -j ACCEPT
	    matched=Yes
	fi

	if [ -z "$matched" ]; then
	    for host1 in $hosts; do
		[ "$host" != "$host1" ] && run_iptables $1 FORWARD -i $interface -o ${host1%:*} $(both_ip_ranges $networks ${host1#*:}) -j ACCEPT
	    done
	fi
    done
}

process_criticalhosts()
{
    local hosts= interface host h options networks criticalhosts=

    strip_file routestopped

    while read interface host options; do
	expandv interface host options

	[ "x$host" = "x-" -o -z "$host" ] && host=0.0.0.0/0 || host=$(separate_list $host)

	if [ -n "$options" ]; then
	    for option in $(separate_list $options); do
		case $option in
		    routeback|source|dest)
			;;
		    critical)
			for h in $host; do
			    criticalhosts="$criticalhosts $interface:$h"
			done
			;;
		    *)
			error_message "WARNING: Unknown routestopped option ignored: $option"
			;;
		esac
	    done
	fi
    done < $TMP_DIR/routestopped

    if [ -n "$criticalhosts" ]; then
	CRITICALHOSTS=$criticalhosts
	progress_message "Critical Hosts are:$CRITICALHOSTS"
    fi

}

#
# Load a Kernel Module
#
loadmodule() # $1 = module name, $2 - * arguments
{
    local modulename=$1
    local modulefile
    local suffix
    moduleloader=modprobe

    if ! qt mywhich modprobe; then
	moduleloader=insmod
    fi

    if ! list_search $modulename $MODULES ; then
	shift

	for suffix in $MODULE_SUFFIX ; do
	    modulefile=$MODULESDIR/${modulename}.${suffix}

	    if [ -f $modulefile ]; then
		case $moduleloader in
		    insmod)
			insmod $modulefile $*
			;;
		    *)
			modprobe $modulename $*
			;;
		esac

		MODULES=$(lsmod | cut -d ' ' -f1)
		break
	    fi
	done
    fi
}

#
# Reload the Modules
#
reload_kernel_modules() {

    [ -z "$MODULESDIR" ] && MODULESDIR=/lib/modules/$(uname -r)/kernel/net/ipv4/netfilter
    MODULES=$(lsmod | cut -d ' ' -f1)

    while read command; do
	eval $command
    done

}

#
# Load kernel modules required for Shorewall
#
load_kernel_modules()
{
    save_modules_dir=$MODULESDIR

    [ -z "$MODULESDIR" ] && \
	MODULESDIR=/lib/modules/$(uname -r)/kernel/net/ipv4/netfilter

    modules=$(find_file modules)

    if [ -f $modules -a -d $MODULESDIR ]; then
	MODULES=$(lsmod | cut -d ' ' -f1)
	progress_message "Loading Modules..."
	. $modules
    fi

    MODULESDIR=$save_modules_dir
}

#
# Call this function to assert mutual exclusion with Shorewall. If you invoke the
# /sbin/shorewall program while holding mutual exclusion, you should pass "nolock" as
# the first argument. Example "shorewall nolock refresh"
#
# This function uses the lockfile utility from procmail if it exists.
# Otherwise, it uses a somewhat race-prone algorithm to attempt to simulate the
# behavior of lockfile.
#
mutex_on()
{
    local try=0
    local lockf=${VARDIR}/lock

    MUTEX_TIMEOUT=${MUTEX_TIMEOUT:-60}

    if [ $MUTEX_TIMEOUT -gt 0 ]; then

	[ -d ${VARDIR} ] || mkdir -p ${VARDIR}

	if qt mywhich lockfile; then
	    lockfile -${MUTEX_TIMEOUT} -r1 ${lockf}
	else
	    while [ -f ${lockf} -a ${try} -lt ${MUTEX_TIMEOUT} ] ; do
		sleep 1
		try=$((${try} + 1))
	    done

	    if  [ ${try} -lt ${MUTEX_TIMEOUT} ] ; then
	        # Create the lockfile
		echo $$ > ${lockf}
	    else
		echo "Giving up on lock file ${lockf}" >&2
	    fi
	fi
    fi
}

#
# Call this function to release mutual exclusion
#
mutex_off()
{
    rm -f ${VARDIR}/lock
}

#
# Determine which version of mktemp is present (if any) and set MKTEMP accortingly:
#
#     None - No mktemp
#     BSD  - BSD mktemp (Mandrake)
#     STD  - mktemp.org mktemp
#
find_mktemp() {
    local mktemp=`mywhich mktemp 2> /dev/null`

    if [ -n "$mktemp" ]; then
	if qt mktemp -V ; then
	    MKTEMP=STD
	else
	    MKTEMP=BSD
	fi
    else
	MKTEMP=None
    fi
}

#
# create a temporary file. If a directory name is passed, the file will be created in
# that directory. Otherwise, it will be created in a temporary directory.
#
mktempfile() {

    [ -z "$MKTEMP" ] && find_mktemp

    if [ $# -gt 0 ]; then
	case "$MKTEMP" in
	    BSD)
		mktemp $1/shorewall.XXXXXX
		;;
	    STD)
		mktemp -p $1 shorewall.XXXXXX
		;;
	    None)
		> $1/shorewall-$$ && echo $1/shorewall-$$
		;;
	    *)
		error_message "ERROR:Internal error in mktempfile"
		;;
	esac
    else
	case "$MKTEMP" in
	    BSD)
		mktemp /tmp/shorewall.XXXXXX
		;;
	    STD)
		mktemp -t shorewall.XXXXXX
		;;
	    None)
		rm -f /tmp/shorewall-$$
		> /tmp/shorewall-$$ && echo /tmp/shorewall-$$
		;;
	    *)
		error_message "ERROR:Internal error in mktempfile"
		;;
	esac
    fi
}

#
# create a temporary directory
#
mktempdir() {

    [ -z "$MKTEMP" ] && find_mktemp

    case "$MKTEMP" in
	STD)
	    mktemp -td shorewall.XXXXXX
	    ;;
	None|BSD)
	    #
	    # Not all versions of the BSD mktemp support the -d option under Linux
	    #
	    qt rm -rf /tmp/shorewall-$$
	    mkdir -p /tmp/shorewall-$$ && chmod 700 /tmp/shorewall-$$ && echo /tmp/shorewall-$$
	    ;;
	*)
	    error_message "ERROR:Internal error in mktempdir"
	    ;;
	esac
}

#
# Read a file and handle "INCLUDE" directives
#

read_file() # $1 = file name, $2 = nest count
{
    local first rest

    if [  -f $1 ]; then
	while read first rest; do
	    if [ "x$first"  = "xINCLUDE" ]; then
		if [ $2 -lt 4 ]; then
		    read_file $(find_file $(expand ${rest%#*})) $(($2 + 1))
		else
		    error_message "WARNING: INCLUDE in $1 ignored (nested too deeply)"
		fi
	    else
		echo "$first $rest"
	    fi
	done < $1
    else
	[ -n "$TERMINATOR" ] && $TERMINATOR "No such file: $1"
	echo "WARNING -- No such file: $1"
    fi
}

#
# Function for including one file into another
#
INCLUDE() {
    . $(find_file $(expand $@))
}

#
# Strip comments and blank lines from a file and place the result in the
# temporary directory
#
strip_file() # $1 = Base Name of the file, $2 = Full Name of File (optional)
{
    local fname

    if [ ! -f $TMP_DIR/$1 ]; then
	[ $# = 1 ] && fname=$(find_file $1) || fname=$2

	if [ -f $fname ]; then
	    read_file $fname 0 | cut -d'#' -f1 | grep -v '^[[:space:]]*$' > $TMP_DIR/$1
	else
	    > $TMP_DIR/$1
	fi
    fi
}

#
# Load an optional library
#
lib_load() # $1 = Name of the Library, $2 = Error Message heading if the library cannot be found
{
    local lib=${SHAREDIR}/lib.$1
    local loaded

    eval loaded=\$LIB_${1}_LOADED

    if [ -z "$loaded" ]; then
	if [ -f $lib ]; then
	    . $lib
	    eval LIB_${1}_LOADED=Yes
	else
	    startup_error "$2 requires the Shorewall library $1 ($lib) which is not installed"
	fi
    fi
}

#
# Determine if an optional library is available
#
lib_avail() # $1 = Name of the Library
{
    [ -f ${SHAREDIR}/lib.$1 ]
}   

strip_file_and_lib_load() # $1 = logical file name, $2 = library to load if the stripped file is non-empty
{
    local f=$(find_file $1)

    strip_file $1 $f

    if [ -s $TMP_DIR/$1 ]; then
	lib_load $2 "A non-empty $1 file ($f)"
	return 0
    fi
    
    return 1
}

#
#  Note: The following set of IP address manipulation functions have anomalous
#        behavior when the shell only supports 32-bit signed arithmatic and
#        the IP address is 128.0.0.0 or 128.0.0.1.
#

LEFTSHIFT='<<'

#
# Convert an IP address in dot quad format to an integer
#
decodeaddr() {
    local x
    local temp=0
    local ifs=$IFS

    IFS=.

    for x in $1; do
	temp=$(( $(( $temp $LEFTSHIFT 8 )) | $x ))
    done

    echo $temp

    IFS=$ifs
}

#
# convert an integer to dot quad format
#
encodeaddr() {
    addr=$1
    local x
    local y=$(($addr & 255))

    for x in 1 2 3 ; do
	addr=$(($addr >> 8))
	y=$(($addr & 255)).$y
    done

    echo $y
}

#
# Enumerate the members of an IP range -- When using a shell supporting only
# 32-bit signed arithmetic, the range cannot span 128.0.0.0.
#
# Comes in two flavors:
#
# ip_range() - produces a mimimal list of network/host addresses that spans
#              the range.
#
# ip_range_explicit() - explicitly enumerates the range.
#
ip_range() {
    local first last l x y z vlsm

    case $1 in
	!*)
	    #
	    # Let iptables complain if it's a range
	    #
	    echo $1
	    return
	    ;;
	[0-9]*.*.*.*-*.*.*.*)
            ;;
	*)
	    echo $1
	    return
	    ;;
    esac

    first=$(decodeaddr ${1%-*})
    last=$(decodeaddr ${1#*-})

    if [ $first -gt $last ]; then
	fatal_error "Invalid IP address range: $1"
    fi

    l=$(( $last + 1 ))

    while [ $first -le $last ]; do
	vlsm=
	x=31
	y=2
	z=1

	while [ $(( $first % $y )) -eq 0 -a $(( $first + $y )) -le $l ]; do
	    vlsm=/$x
	    x=$(( $x - 1 ))
	    z=$y
	    y=$(( $y * 2 ))
	done

	echo $(encodeaddr $first)$vlsm
	first=$(($first + $z))
    done
}

ip_range_explicit() {
    local first last

    case $1 in
    [0-9]*.*.*.*-*.*.*.*)
	;;
    *)
	echo $1
	return
	;;
    esac

    first=$(decodeaddr ${1%-*})
    last=$(decodeaddr ${1#*-})

    if [ $first -gt $last ]; then
	fatal_error "Invalid IP address range: $1"
    fi

    while [ $first -le $last ]; do
	echo $(encodeaddr $first)
	first=$(($first + 1))
    done
}

#
# Netmask from CIDR
#
ip_netmask() {
    local vlsm=${1#*/}

    [ $vlsm -eq 0 ] && echo 0 || echo $(( -1 $LEFTSHIFT $(( 32 - $vlsm )) ))
}

#
# Network address from CIDR
#
ip_network() {
    local decodedaddr=$(decodeaddr ${1%/*})
    local netmask=$(ip_netmask $1)

    echo $(encodeaddr $(($decodedaddr & $netmask)))
}

#
# The following hack is supplied to compensate for the fact that many of
# the popular light-weight Bourne shell derivatives don't support XOR ("^").
#

ip_broadcast() {
    local x=$(( 32 - ${1#*/} ))

    [ $x -eq 0 ] && echo -1 || echo $(( $(( 1 $LEFTSHIFT $x )) - 1 ))
}

#
# Calculate broadcast address from CIDR
#
broadcastaddress() {
    local decodedaddr=$(decodeaddr ${1%/*})
    local netmask=$(ip_netmask $1)
    local broadcast=$(ip_broadcast $1)

    echo $(encodeaddr $(( $(($decodedaddr & $netmask)) | $broadcast )))
}

#
# Test for network membership
#
in_network() # $1 = IP address, $2 = CIDR network
{
    local netmask=$(ip_netmask $2)

    test $(( $(decodeaddr $1) & $netmask)) -eq $(( $(decodeaddr ${2%/*}) & $netmask ))
}

#
# Netmask to VLSM
#
ip_vlsm() {
    local mask=$(decodeaddr $1)
    local vlsm=0
    local x=$(( 128 << 24 )) # 0x80000000

    while [ $(( $x & $mask )) -ne 0 ]; do
	[ $mask -eq $x ] && mask=0 || mask=$(( $mask $LEFTSHIFT 1 )) # Not all shells shift 0x80000000 left properly.
	vlsm=$(($vlsm + 1))
    done

    if [ $(( $mask & 2147483647 )) -ne 0 ]; then # 2147483647 = 0x7fffffff
	echo "Invalid net mask: $1" >&2
    else
	echo $vlsm
    fi
}


#
# Chain name base for an interface -- replace all periods with underscores in the passed name.
#                                     The result is echoed (less trailing "+").
#
chain_base() #$1 = interface
{
    local c=${1%%+}

    while true; do
	case $c in
	    *.*)
		c="${c%.*}_${c##*.}"
		;;
	    *-*)
		c="${c%-*}_${c##*-}"
		;;
	    *%*)
		c="${c%\%*}_${c##*%}"
		;;
	    *)
		echo ${c:=common}
		return
		;;
	esac
    done
}

#
# Query NetFilter about the existence of a filter chain
#
chain_exists() # $1 = chain name
{
    qt $IPTABLES -L $1 -n
}

#
# Loosly Match the name of an interface
#

if_match() # $1 = Name in interfaces file - may end in "+"
           # $2 = Full interface name - may also end in "+"
{
    local pattern=${1%+}

    case $1 in
	*+)
	    test  "x$(echo $2 | truncate ${#pattern} )" = "x${pattern}"
	    ;;
	*)
	    test "x$1" = "x$2"
	    ;;
    esac
}

#
# Source IP range
#
source_ip_range() # $1 = Address or Address Range
{
    [ $# -gt 0 ] && case $1 in
	*.*.*.*-*.*.*.*)
	    case $1 in
		!*)
		    iprange_echo "! --src-range ${1#!}"
		    ;;
		*)
		    iprange_echo "--src-range $1"
		    ;;
	    esac
	    ;;
	!+*)
	    echo "-m set ! $(get_set_flags ${1#!} src)"
	    ;;
	+*)
	    echo "-m set $(get_set_flags $1 src)"
	    ;;
	*)
	    echo "-s $1"
	    ;;
    esac
}

#
# Destination IP range
#
dest_ip_range() # $1 = Address or Address Range
{
    [ $# -gt 0 ] && case $1 in
	*.*.*.*-*.*.*.*)
	    case $1 in
		!*)
		    iprange_echo "! --dst-range ${1#!}"
		    ;;
		*)
		    iprange_echo "--dst-range $1"
		    ;;
	    esac
	    ;;
	!+*)
	    echo "-m set ! $(get_set_flags ${1#!} dst)"
	    ;;
	+*)
	    echo "-m set $(get_set_flags $1 dst)"
	    ;;
	*)
	    echo "-d $1"
	    ;;
    esac
}

both_ip_ranges() # $1 = Source address or range, $2 = dest address or range
{
    local rangeprefix= setprefix= rangematch= setmatch=

    case $1 in
	*.*.*.*-*.*.*.*)
	    rangeprefix="-m iprange"
	    rangematch="--src-range $1"
	    ;;
	!+*)
	    setprefix="-m set"
	    setmatch="! $(get_set_flags ${1#!} src)"
	    ;;
	+*)
	    setprefix="-m set"
	    setmatch="$(get_set_flags $1 src)"
	    ;;
	*)
	    rangematch="-s $1"
	    ;;
    esac

    case $2 in
	*.*.*.*-*.*.*.*)
	    rangeprefix="-m iprange"
	    rangematch="$rangematch --dst-range $2"
	    ;;
	!+*)
	    setprefix="-m set"
	    match="$setmatch ! $(get_set_flags ${2#!} dst)"
	    ;;
	+*)
	    setprefix="-m set"
	    setmatch="$setmatch $(get_set_flags $2 dst)"
	    ;;
	*)
	    rangematch="$rangematch -d $2"
	    ;;
    esac

    echo "$rangeprefix $rangematch $setprefix $setmatch"
}

#
# Find the value 'dev' in the passed arguments then echo the next value
#

find_device() {
    while [ $# -gt 1 ]; do
	[ "x$1" = xdev ] && echo $2 && return
	shift
    done
}

#
# Find the value 'via' in the passed arguments then echo the next value
#

find_gateway() {
    while [ $# -gt 1 ]; do
	[ "x$1" = xvia ] && echo $2 && return
	shift
    done
}

#
# Find the value 'mtu' in the passed arguments then echo the next value
#

find_mtu() {
    while [ $# -gt 1 ]; do
	[ "x$1" = xmtu ] && echo $2 && return
	shift
    done
}

#
# Find the value 'peer' in the passed arguments then echo the next value up to
# "/"
#

find_peer() {
    while [ $# -gt 1 ]; do
	[ "x$1" = xpeer ] && echo ${2%/*} && return
	shift
    done
}

#
# Find the interfaces that have a route to the passed address - the default
# route is not used.
#

find_rt_interface() {
    ip route ls | while read addr rest; do
	case $addr in
	    */*)
		in_network ${1%/*} $addr && echo $(find_device $rest)
		;;
	    default)
		;;
	    *)
		if [ "$addr" = "$1" -o "$addr/32" = "$1" ]; then
		    echo $(find_device $rest)
		fi
		;;
	esac
    done
}

#
# Try to find the gateway through an interface looking for 'nexthop'

find_nexthop() # $1 = interface
{
    echo $(find_gateway `ip route ls | grep "[[:space:]]nexthop.* $1"`)
}

#
# Find the default route's interface
#
find_default_interface() {
    ip route ls | while read first rest; do
	[ "$first" = default ] && echo $(find_device $rest) && return
    done
}

#
# Echo the name of the interface(s) that will be used to send to the
# passed address
#

find_interface_by_address() {
    local dev="$(find_rt_interface $1)"
    local first rest

    [ -z "$dev" ] && dev=$(find_default_interface)

    [ -n "$dev" ] && echo $dev
}

#
# Find the interface with the passed MAC address
#

find_interface_by_mac() {
    local mac=$1 first second rest dev

    ip link ls | while read first second rest; do
	case $first in
	    *:)
                dev=$second
		;;
	    *)
	        if [ "$second" = $mac ]; then
		    echo ${dev%:}
		    return
		fi
	esac
    done
}

#
# Determine if Interface is up
#
interface_is_up() {
    [ -n "$(ip link ls dev $1 | grep -e '[<,]UP[,>]')" ]
}

#
# Find interface address--returns the first IP address assigned to the passed
# device
#
find_first_interface_address() # $1 = interface
{
    #
    # get the line of output containing the first IP address
    #
    addr=$(ip -f inet addr show $1 2> /dev/null | grep 'inet .* global' | head -n1)
    #
    # If there wasn't one, bail out now
    #
    [ -n "$addr" ] || fatal_error "Can't determine the IP address of $1"
    #
    # Strip off the trailing VLSM mask (or the peer IP in case of a P-t-P link)
    # along with everything else on the line
    #
    echo $addr | sed 's/\s*inet //;s/\/.*//;s/ peer.*//'
}

find_first_interface_address_if_any() # $1 = interface
{
    #
    # get the line of output containing the first IP address
    #
    addr=$(ip -f inet addr show $1 2> /dev/null | grep 'inet .* global' | head -n1)
    #
    # Strip off the trailing VLSM mask (or the peer IP in case of a P-t-P link)
    # along with everything else on the line
    #
    [ -n "$addr" ] && echo $addr | sed 's/\s*inet //;s/\/.*//;s/ peer.*//' || echo 0.0.0.0
}

#
# Find interface addresses--returns the set of addresses assigned to the passed
# device
#
find_interface_addresses() # $1 = interface
{
    ip -f inet addr show $1 | grep inet\  | sed 's/\s*inet //;s/\/.*//;s/ peer.*//'
}

#
#  echo the list of networks routed out of a given interface
#
get_routed_networks() # $1 = interface name, $2-n = Fatal error message
{
    local address
    local rest

    ip route show dev $1 2> /dev/null |
	while read address rest; do
	    if [ "x$address" = xdefault ]; then
		if [ $# -gt 1 ]; then
		    shift
		    fatal_error "$@"
		else
		    "WARNING: default route ignored on interface $1"
		fi
	    else
		[ "$address" = "${address%/*}" ] && address="${address}/32"
		echo $address
	    fi
        done
}

#
# Internal version of 'which'
#
mywhich() {
    local dir

    for dir in $(split $PATH); do
	if [ -x $dir/$1 ]; then
	    echo $dir/$1
	    return 0
	fi
    done

    return 2
}

#
# Set the Shorewall state
#
set_state () # $1 = state
{
    echo "$1 ($(date))" > ${VARDIR}/state
}

#
# Determine which optional facilities are supported by iptables/netfilter
#
determine_capabilities() {
    qt $IPTABLES -t nat    -L -n && NAT_ENABLED=Yes    || NAT_ENABLED=
    qt $IPTABLES -t mangle -L -n && MANGLE_ENABLED=Yes || MANGLE_ENABLED=

    CONNTRACK_MATCH=
    MULTIPORT=
    XMULTIPORT=
    POLICY_MATCH=
    PHYSDEV_MATCH=
    IPRANGE_MATCH=
    RECENT_MATCH=
    OWNER_MATCH=
    IPSET_MATCH=
    CONNMARK=
    XCONNMARK=
    CONNMARK_MATCH=
    XCONNMARK_MATCH=
    RAW_TABLE=
    IPP2P_MATCH=
    LENGTH_MATCH=
    CLASSIFY_TARGET=
    ENHANCED_REJECT=
    USEPKTTYPE=
    KLUDGEFREE=
    MARK=
    XMARK=
    MANGLE_FORWARD=

    qt $IPTABLES -N fooX1234
    qt $IPTABLES -A fooX1234 -m conntrack --ctorigdst 192.168.1.1 -j ACCEPT             && CONNTRACK_MATCH=Yes
    qt $IPTABLES -A fooX1234 -p tcp -m multiport --dports 21,22 -j ACCEPT               && MULTIPORT=Yes
    qt $IPTABLES -A fooX1234 -p tcp -m multiport --dports 21:22 -j ACCEPT               && XMULTIPORT=Yes
    qt $IPTABLES -A fooX1234 -m policy --pol ipsec --mode tunnel --dir in -j ACCEPT     && POLICY_MATCH=Yes

    if qt $IPTABLES -A fooX1234 -m physdev --physdev-in eth0 -j ACCEPT; then
	PHYSDEV_MATCH=Yes
    fi

    if qt $IPTABLES -A fooX1234 -m iprange --src-range 192.168.1.5-192.168.1.124 -j ACCEPT; then
	IPRANGE_MATCH=Yes
	if [ -z "${KLUDGEFREE}" ]; then
	    qt $IPTABLES -A fooX1234 -m iprange --src-range 192.168.1.5-192.168.1.124 -m iprange --dst-range 192.168.1.5-192.168.1.124 -j ACCEPT && KLUDGEFREE=Yes
	fi
    fi

    qt $IPTABLES -A fooX1234 -m recent --update -j ACCEPT     && RECENT_MATCH=Yes
    qt $IPTABLES -A fooX1234 -m owner --uid-owner 0 -j ACCEPT && OWNER_MATCH=Yes

    if qt $IPTABLES -A fooX1234 -m connmark --mark 2  -j ACCEPT; then
	CONNMARK_MATCH=Yes
	qt $IPTABLES -A fooX1234 -m connmark --mark 2/0xFF -j ACCEPT && XCONNMARK_MATCH=Yes
    fi

    qt $IPTABLES -A fooX1234 -p tcp -m ipp2p --ipp2p -j ACCEPT            && IPP2P_MATCH=Yes
    qt $IPTABLES -A fooX1234 -m length --length 10:20 -j ACCEPT           && LENGTH_MATCH=Yes
    qt $IPTABLES -A fooX1234 -j REJECT --reject-with icmp-host-prohibited && ENHANCED_REJECT=Yes

    if [ -n "$MANGLE_ENABLED" ]; then
	qt $IPTABLES -t mangle -N fooX1234

	if qt $IPTABLES -t mangle -A fooX1234 -j MARK --set-mark 1; then
	    MARK=Yes
	    qt $IPTABLES -t mangle -A fooX1234 -j MARK --and-mark 0xFF && XMARK=Yes
	fi

	if qt $IPTABLES -t mangle -A fooX1234 -j CONNMARK --save-mark; then
	    CONNMARK=Yes
	    qt $IPTABLES -t mangle -A fooX1234 -j CONNMARK --save-mark --mask 0xFF && XCONNMARK=Yes
	fi

	qt $IPTABLES -t mangle -A fooX1234 -j CLASSIFY --set-class 1:1 && CLASSIFY_TARGET=Yes
	qt $IPTABLES -t mangle -F fooX1234
	qt $IPTABLES -t mangle -X fooX1234
	qt $IPTABLES -t mangle -L FORWARD -n && MANGLE_FORWARD=Yes
    fi

    qt $IPTABLES -t raw	   -L -n && RAW_TABLE=Yes

    if qt mywhich ipset; then
	qt ipset -X fooX1234 # Just in case something went wrong the last time

	if qt ipset -N fooX1234 iphash ; then
	    if qt $IPTABLES -A fooX1234 -m set --set fooX1234 src -j ACCEPT; then
		qt $IPTABLES -D fooX1234 -m set --set fooX1234 src -j ACCEPT
		IPSET_MATCH=Yes
	    fi
	    qt ipset -X fooX1234
	fi
    fi

    qt $IPTABLES -A fooX1234 -m pkttype --pkt-type broadcast -j ACCEPT && USEPKTTYPE=Yes

    qt $IPTABLES -F fooX1234
    qt $IPTABLES -X fooX1234
}

report_capabilities() {
    report_capability() # $1 = Capability Description , $2 Capability Setting (if any)
    {
	local setting=
	
	[ "x$2" = "xYes" ] && setting="Available" || setting="Not available"
	
	echo "  " $1: $setting
    }

    if [ $VERBOSE -gt 1 ]; then
	echo "Shorewall has detected the following iptables/netfilter capabilities:"
	report_capability "NAT" $NAT_ENABLED
	report_capability "Packet Mangling" $MANGLE_ENABLED
	report_capability "Multi-port Match" $MULTIPORT
	[ -n "$MULTIPORT" ] && report_capability "Extended Multi-port Match" $XMULTIPORT
	report_capability "Connection Tracking Match" $CONNTRACK_MATCH
	report_capability "Packet Type Match" $USEPKTTYPE
	report_capability "Policy Match" $POLICY_MATCH
	report_capability "Physdev Match" $PHYSDEV_MATCH
	report_capability "Packet length Match" $LENGTH_MATCH
	report_capability "IP range Match" $IPRANGE_MATCH
	report_capability "Recent Match" $RECENT_MATCH
	report_capability "Owner Match" $OWNER_MATCH
	report_capability "Ipset Match" $IPSET_MATCH
	report_capability "CONNMARK Target" $CONNMARK
	[ -n "$CONNMARK" ] && report_capability "Extended CONNMARK Target" $XCONNMARK
	report_capability "Connmark Match" $CONNMARK_MATCH
	[ -n "$CONNMARK_MATCH" ] && report_capability "Extended Connmark Match" $XCONNMARK_MATCH
	report_capability "Raw Table" $RAW_TABLE
	report_capability "IPP2P Match" $IPP2P_MATCH
	report_capability "CLASSIFY Target" $CLASSIFY_TARGET
	report_capability "Extended REJECT" $ENHANCED_REJECT
	report_capability "Repeat match" $KLUDGEFREE
	report_capability "MARK Target" $MARK
	[ -n "$MARK" ] && report_capability "Extended MARK Target" $XMARK
	report_capability "Mangle FORWARD Chain" $MANGLE_FORWARD
    fi

    [ -n "$PKTTYPE" ] || USEPKTTYPE=

}

report_capabilities1() {
    report_capability1() # $1 = Capability
    {
	eval echo $1=\$$1
    }

    echo "#"
    echo "# Shorewall $VERSION detected the following iptables/netfilter capabilities - $(date)"
    echo "#"
    report_capability1 NAT_ENABLED
    report_capability1 MANGLE_ENABLED
    report_capability1 MULTIPORT
    report_capability1 XMULTIPORT
    report_capability1 CONNTRACK_MATCH
    report_capability1 USEPKTTYPE
    report_capability1 POLICY_MATCH
    report_capability1 PHYSDEV_MATCH
    report_capability1 LENGTH_MATCH
    report_capability1 IPRANGE_MATCH
    report_capability1 RECENT_MATCH
    report_capability1 OWNER_MATCH
    report_capability1 IPSET_MATCH
    report_capability1 CONNMARK
    report_capability1 XCONNMARK
    report_capability1 CONNMARK_MATCH
    report_capability1 XCONNMARK_MATCH
    report_capability1 RAW_TABLE
    report_capability1 IPP2P_MATCH
    report_capability1 CLASSIFY_TARGET
    report_capability1 ENHANCED_REJECT
    report_capability1 KLUDGEFREE
    report_capability1 MARK
    report_capability1 XMARK
    report_capability1 MANGLE_FORWARD
}

#
# Delete IP address
#
del_ip_addr() # $1 = address, $2 = interface
{
    [ $(find_first_interface_address_if_any $2) = $1 ] || qt ip addr del $1 dev $2
}

# Add IP Aliases
#
add_ip_aliases() # $* = List of addresses
{
    local addresses external interface inet cidr rest val arping=$(mywhich arping)

    address_details()
    {
	#
	# Folks feel uneasy if they don't see all of the same
	# decoration on these IP addresses that they see when their
	# distro's net config tool adds them. In an attempt to reduce
	# the anxiety level, we have the following code which sets
	# the VLSM and BRD from an existing address in the same networks
	#
	# Get all of the lines that contain inet addresses with broadcast
	#
	ip -f inet addr show $interface 2> /dev/null | grep 'inet.*brd' | while read inet cidr rest ; do
	    case $cidr in
		*/*)
		    if in_network $external $cidr; then
			echo "/${cidr#*/} brd $(broadcastaddress $cidr)"
			break
		    fi
		    ;;
	    esac
	done
    }

    do_one()
    {
	val=$(address_details)

	ip addr add ${external}${val} dev $interface $label
	[ -n "$arping" ] && qt $arping -U -c 2 -I $interface $external
	echo "$external $interface" >> $STATEDIR/nat
	[ -n "$label" ] && label="with $label"
	progress_message "   IP Address $external added to interface $interface $label"
    }

    progress_message "Adding IP Addresses..."

    while [ $# -gt 0 ]; do
	external=$1
	interface=$2
	label=

	if [ "$interface" != "${interface%:*}" ]; then
	    label="${interface#*:}"
	    interface="${interface%:*}"
	    label="label $interface:$label"
	fi

	shift 2

	list_search $external $(find_interface_addresses $interface) || do_one
    done
}

detect_gateway() # $1 = interface
{
    local interface=$1
    #
    # First assume that this is some sort of point-to-point interface
    #
    gateway=$( find_peer $(ip addr ls $interface ) )
    #
    # Maybe there's a default route through this gateway already
    #
    [ -n "$gateway" ] || gateway=$(find_gateway $(ip route ls dev $interface))
    #
    # Last hope -- is there a load-balancing route through the interface?
    #
    [ -n "$gateway" ] || gateway=$(find_nexthop $interface)
    #
    # Be sure we found one
    #
    [ -n "$gateway" ] && echo $gateway
}

#
# Disable IPV6
#
disable_ipv6() {
    local foo="$(ip -f inet6 addr ls 2> /dev/null)"

    if [ -n "$foo" ]; then
	if qt mywhich ip6tables; then
	    ip6tables -P FORWARD DROP
	    ip6tables -P INPUT DROP
	    ip6tables -P OUTPUT DROP
	    ip6tables -F
	    ip6tables -X
	    ip6tables -A OUTPUT -o lo -j ACCEPT
	    ip6tables -A INPUT -i lo -j ACCEPT
	else
	    error_message "WARNING: DISABLE_IPV6=Yes in shorewall.conf but this system does not appear to have ip6tables"
	fi
    fi
}

#
# Add a logging rule.
#
log_rule_limit() # $1 = log level, $2 = chain, $3 = display Chain $4 = disposition , $5 = rate limit $6=log tag $7=command $... = predicates for the rule
{
    local level=$1
    local chain=$2
    local displayChain=$3
    local disposition=$4
    local rulenum=
    local limit=
    local tag=${6:+$6 }
    local command=${7:--A}
    local prefix
    local base=$(chain_base $displayChain)

    limit="${5:-$LOGLIMIT}" # Do this here rather than in the declaration above to appease /bin/ash.

    shift 7

    if [ -n "$tag" -a -n "$LOGTAGONLY" ]; then
	displayChain=$tag
	tag=
    fi

    if [ -n "$LOGRULENUMBERS" ]; then
	eval rulenum=\$${base}_logrules

	rulenum=${rulenum:-1}

	prefix="$(printf "$LOGFORMAT" $displayChain $rulenum $disposition)${tag}"

	rulenum=$(($rulenum + 1))
	eval ${base}_logrules=$rulenum
    else
	prefix="$(printf "$LOGFORMAT" $displayChain $disposition)${tag}"
    fi

    if [ ${#prefix} -gt 29 ]; then
	prefix="$(echo $prefix | truncate 29)"
	error_message "WARNING: Log Prefix shortened to \"$prefix\""
    fi

    [ "$PROGRAM" = compiler ] && prefix="\"$prefix\""

    case $level in
	ULOG)
	    run_iptables $command $chain $@ $limit -j ULOG $LOGPARMS --ulog-prefix "$prefix"
	    ;;
	*)
	    run_iptables $command $chain $@ $limit -j LOG $LOGPARMS --log-level $level --log-prefix "$prefix"
	    ;;
    esac

    if [ $? -ne 0 ] ; then
	[ -z "$STOPPING" ] && { stop_firewall; exit 2; }
    fi
}

log_rule() # $1 = log level, $2 = chain, $3 = disposition , $... = predicates for the rule
{
    local level=$1
    local chain=$2
    local disposition=$3

    shift 3

    log_rule_limit $level $chain $chain $disposition "$LOGLIMIT" "" -A $@
}

#
# Check that a mark value or mask is less that 256 or that it is less than 65536 and
# that it's lower 8 bits are zero.
#
verify_mark() # $1 = value to test
{
    verify_mark2()
    {
	case $1 in
	    0*)
		[ $(($1)) -lt 256 ] && return 0
		[ -n "$HIGH_ROUTE_MARKS" ] || return 1
		[ $(($1)) -gt 65535 ] && return 1
		return $(($1 & 0xFF))
		;;
	    [1-9]*)
		[ $1 -lt 256 ] && return 0
		[ -n "$HIGH_ROUTE_MARKS" ] || return 1
		[ $1 -gt 65535 ] && return 1
		return $(($1 & 0xFF))
		;;
	    *)
		return 2
		;;
	esac
    }

    verify_mark2 $1 || fatal_error "Invalid Mark or Mask value: $1"
}

#
# Detect a device's MTU
#
get_device_mtu() # $1 = device
{
    local output="$(ip link ls dev $1 2> /dev/null)" # quotes required for /bin/ash

    if [ -n "$output" ]; then
	echo $(find_mtu $output)
    else
	echo 1500
    fi
}

delete_tc1()
{
    clear_one_tc() {
        tc qdisc del dev $1 root 2> /dev/null
        tc qdisc del dev $1 ingress 2> /dev/null

    }

    run_user_exit tcclear

    run_ip link list | \
    while read inx interface details; do
        case $inx in
            [0-9]*)
                clear_one_tc ${interface%:}
                ;;
            *)
                ;;
        esac
    done
}

#
# Determine the value for a parameter that defaults to Yes
#
added_param_value_yes() # $1 = Parameter Name, $2 = Parameter value
{
    local val="$2"

    if [ -z "$val" ]; then
	echo "Yes"
    else case $val in
	[Yy][Ee][Ss])
	    echo "Yes"
	    ;;
	[Nn][Oo])
	    echo ""
	    ;;
	*)
	    startup_error "Invalid value ($val) for $1"
	    ;;
	esac
    fi
}

#
# Determine the value for a parameter that defaults to No
#
added_param_value_no() # $1 = Parameter Name, $2 = Parameter value
{
    local val="$2"

    if [ -z "$val" ]; then
	echo ""
    else case $val in
	[Yy][Ee][Ss])
	    echo "Yes"
	    ;;
	[Nn][Oo])
	    echo ""
	    ;;
	*)
	    startup_error "Invalid value ($val) for $1"
	    ;;
	esac
    fi
}

#
# Initialize this program
#
do_initialize() {

    # Run all utility programs using the C locale
    #
    # Thanks to Vincent Planchenault for this tip #

    export LC_ALL=C

    # Make sure umask is sane
    umask 077

    PATH=/sbin:/bin:/usr/sbin:/usr/bin:/usr/local/sbin:/usr/local/bin
    #
    # Establish termination function
    #
    TERMINATOR=fatal_error
    #
    # Clear all configuration variables
    #
    VERSION=
    IPTABLES=
    FW=
    SUBSYSLOCK=
    ALLOWRELATED=Yes
    LOGRATE=
    LOGBURST=
    LOGPARMS=
    LOGLIMIT=
    ADD_IP_ALIASES=
    ADD_SNAT_ALIASES=
    TC_ENABLED=
    BLACKLIST_DISPOSITION=
    BLACKLIST_LOGLEVEL=
    CLAMPMSS=
    ROUTE_FILTER=
    LOG_MARTIANS=
    DETECT_DNAT_IPADDRS=
    MUTEX_TIMEOUT=
    FORWARDPING=
    MACLIST_DISPOSITION=
    MACLIST_LOG_LEVEL=
    TCP_FLAGS_DISPOSITION=
    TCP_FLAGS_LOG_LEVEL=
    RFC1918_LOG_LEVEL=
    MARK_IN_FORWARD_CHAIN=
    VERSION_FILE=
    LOGFORMAT=
    LOGRULENUMBERS=
    ADMINISABSENTMINDED=
    BLACKLISTNEWONLY=
    MODULE_SUFFIX=
    ACTIONS=
    USEDACTIONS=
    SMURF_LOG_LEVEL=
    DISABLE_IPV6=
    BRIDGING=
    DYNAMIC_ZONES=
    PKTTYPE=
    USEPKTYPE=
    RETAIN_ALIASES=
    DELAYBLACKLISTLOAD=
    LOGTAGONLY=
    LOGALLNEW=
    RFC1918_STRICT=
    MACLIST_TTL=
    SAVE_IPSETS=
    RESTOREFILE=
    MAPOLDACTIONS=
    IMPLICIT_CONTINUE=
    HIGH_ROUTE_MARKS=
    TC_EXPERT=

    OUTPUT=
    TMP_DIR=
    ALL_INTERFACES=
    ROUTEMARK_INTERFACES=
    IPSECMARK=256
    PROVIDERS=
    CRITICALHOSTS=
    IPSECFILE=
    EXCLUSION_SEQ=1
    STOPPING=
    HAVE_MUTEX=
    ALIASES_TO_ADD=
    SECTION=ESTABLISHED
    SECTIONS=
    ALL_PORTS=

    TMP_DIR=$(mktempdir)

    [ -n "$TMP_DIR" ] && chmod 700 $TMP_DIR || \
       fatal_error "Can't create a temporary directory"

    case $PROGRAM in
	compiler)
	    trap "[ -n "$OUTPUT" ] && rm -f $OUTPUT;rm -rf $TMP_DIR; exit 2" 1 2 3 4 5 6 9
	    ;;
	firewall)
	    trap "[ -n "$RESTOREBASE" ] && rm -f $RESTOREBASE;rm -rf $TMP_DIR; my_mutex_off; exit 2" 1 2 3 4 5 6 9
	    ;;
    esac

    ensure_config_path

    VERSION_FILE=$SHAREDIR/version

    [ -f $VERSION_FILE ] && VERSION=$(cat $VERSION_FILE)

    run_user_exit params

    config=$(find_file shorewall.conf)

    if [ -f $config ]; then
	if [ -r $config ]; then
	    progress_message "Processing $config..."
	    . $config
	else
	    fatal_error "Cannot read $config (Hint: Are you root?)"
	fi
    else
	fatal_error "$config does not exist!"
    fi

    #
    # Restore CONFIG_PATH if the shorewall.conf file cleared it
    #
    ensure_config_path
    #
    # Determine the capabilities of the installed iptables/netfilter
    # We load the kernel modules here to accurately determine
    # capabilities when module autoloading isn't enabled.
    #
    PKTTYPE=$(added_param_value_no PKTTYPE $PKTTYPE)

    [ -n "${MODULE_SUFFIX:=o gz ko o.gz ko.gz}" ]

    if [ -z "$EXPORT" -a "$(whoami)" = root ]; then

	load_kernel_modules

	if [ -z "$IPTABLES" ]; then
	    IPTABLES=$(mywhich iptables 2> /dev/null)

	    [ -z "$IPTABLES" ] && fatal_error "Can't find iptables executable"
	else
	    [ -e "$IPTABLES" ] || fatal_error "\$IPTABLES=$IPTABLES does not exist or is not executable"
	fi
	determine_capabilities

    else
	f=$(find_file capabilities)

	[ -f $f ] && . $f || fatal_error "The -e flag requires a capabilities file"
    fi

    ALLOWRELATED="$(added_param_value_yes ALLOWRELATED $ALLOWRELATED)"
    [ -n "$ALLOWRELATED" ] || \
	fatal_error "ALLOWRELATED=No is not supported"
    ADD_IP_ALIASES="$(added_param_value_yes ADD_IP_ALIASES $ADD_IP_ALIASES)"

    if [ -n "${LOGRATE}${LOGBURST}" ]; then
	LOGLIMIT="--match limit"
	[ -n "$LOGRATE" ]  && LOGLIMIT="$LOGLIMIT --limit $LOGRATE"
	[ -n "$LOGBURST" ] && LOGLIMIT="$LOGLIMIT --limit-burst $LOGBURST"
    fi

    if [ -n "$IP_FORWARDING" ]; then
	case "$IP_FORWARDING" in
	[Oo][Nn]|[Oo][Ff][Ff]|[Kk][Ee][Ee][Pp])
	    ;;
	*)
	    fatal_error "Invalid value ($IP_FORWARDING) for IP_FORWARDING"
	    ;;
	esac
    else
	IP_FORWARDING=On
    fi

   [ -n "${BLACKLIST_DISPOSITION:=DROP}" ]

    case "$CLAMPMSS" in
	[0-9]*)
	    ;;
	*)
	    CLAMPMSS=$(added_param_value_no CLAMPMSS $CLAMPMSS)
	    ;;
    esac

    ADD_SNAT_ALIASES=$(added_param_value_no ADD_SNAT_ALIASES $ADD_SNAT_ALIASES)
    ROUTE_FILTER=$(added_param_value_no ROUTE_FILTER $ROUTE_FILTER)
    LOG_MARTIANS=$(added_param_value_no LOG_MARTIANS $LOG_MARTIANS)
    DETECT_DNAT_IPADDRS=$(added_param_value_no DETECT_DNAT_IPADDRS $DETECT_DNAT_IPADDRS)
    FORWARDPING=$(added_param_value_no FORWARDPING $FORWARDPING)
    [ -n "$FORWARDPING" ] && \
	fatal_error "FORWARDPING=Yes is no longer supported"

    maclist_target=reject

    if [ -n "$MACLIST_DISPOSITION" ] ; then
	case $MACLIST_DISPOSITION in
	    REJECT)
		;;
	    DROP)
		maclist_target=DROP
		;;
	    ACCEPT)
		maclist_target=RETURN
		;;
	    *)
		fatal_error "Invalid value ($MACLIST_DISPOSITION) for MACLIST_DISPOSITION"
		;;
	esac
    else
	MACLIST_DISPOSITION=REJECT
    fi

    if [ -n "$TCP_FLAGS_DISPOSITION" ] ; then
	case $TCP_FLAGS_DISPOSITION in
	    REJECT|ACCEPT|DROP)
		;;
	    *)
		fatal_error "Invalid value ($TCP_FLAGS_DISPOSITION) for TCP_FLAGS_DISPOSITION"
		;;
	esac
    else
	TCP_FLAGS_DISPOSITION=DROP
    fi

    [ -n "${RFC1918_LOG_LEVEL:=info}" ]

    MARK_IN_FORWARD_CHAIN=$(added_param_value_no MARK_IN_FORWARD_CHAIN $MARK_IN_FORWARD_CHAIN)
    [ -n "$MARK_IN_FORWARD_CHAIN" ] && MARKING_CHAIN=tcfor || MARKING_CHAIN=tcpre
    CLEAR_TC=$(added_param_value_yes CLEAR_TC $CLEAR_TC)

    if [ -n "$LOGFORMAT" ]; then
	if [ -n "$(echo $LOGFORMAT | grep '%d')" ]; then
	    LOGRULENUMBERS=Yes
	    temp=$(printf "$LOGFORMAT" fooxx 1 barxx 2> /dev/null)
	    if [ $? -ne 0 ]; then
		fatal_error "Invalid LOGFORMAT string: \"$LOGFORMAT\""
	    fi
	else
	    temp=$(printf "$LOGFORMAT" fooxx barxx 2> /dev/null)
	    if [ $? -ne 0 ]; then
		fatal_error "Invalid LOGFORMAT string: \"$LOGFORMAT\""
	    fi
	fi

	[ ${#temp} -le 29 ] || fatal_error "LOGFORMAT string is longer than 29 characters: \"$LOGFORMAT\""
    else
	LOGFORMAT="Shorewall:%s:%s:"
    fi
    ADMINISABSENTMINDED=$(added_param_value_no ADMINISABSENTMINDED $ADMINISABSENTMINDED)
    BLACKLISTNEWONLY=$(added_param_value_no BLACKLISTNEWONLY $BLACKLISTNEWONLY)
    DISABLE_IPV6=$(added_param_value_no DISABLE_IPV6 $DISABLE_IPV6)
    BRIDGING=$(added_param_value_no BRIDGING $BRIDGING)

    DYNAMIC_ZONES=$(added_param_value_no DYNAMIC_ZONES $DYNAMIC_ZONES)
    if [ -n "$DYNAMIC_ZONES" ]; then
	[ -n "$EXPORT" ] && fatal_error "DYNAMIC_ZONES=Yes is incompatible with the -e option"
	lib_avail dynamiczones || error_message "WARNING: DYNAMIC_ZONES=Yes requires the Shorewall dynamiczones library (${SHAREDIR}/lib.dynamiczones) which is not installed"
    fi

    STARTUP_ENABLED=$(added_param_value_yes STARTUP_ENABLED $STARTUP_ENABLED)
    RETAIN_ALIASES=$(added_param_value_no RETAIN_ALIASES $RETAIN_ALIASES)
    [ -n "${ADD_IP_ALIASES}${ADD_SNAT_ALIASES}" ] || RETAIN_ALIASES=
    DELAYBLACKLISTLOAD=$(added_param_value_no DELAYBLACKLISTLOAD $DELAYBLACKLISTLOAD)
    LOGTAGONLY=$(added_param_value_no LOGTAGONLY $LOGTAGONLY)
    RFC1918_STRICT=$(added_param_value_no RFC1918_STRICT $RFC1918_STRICT)
    SAVE_IPSETS=$(added_param_value_no SAVE_IPSETS $SAVE_IPSETS)
    MAPOLDACTIONS=$(added_param_value_yes MAPOLDACTIONS $MAPOLDACTIONS)
    FASTACCEPT=$(added_param_value_no FASTACCEPT $FASTACCEPT)
    IMPLICIT_CONTINUE=$(added_param_value_no IMPLICIT_CONTINUE $IMPLICIT_CONTINUE)
    HIGH_ROUTE_MARKS=$(added_param_value_no HIGH_ROUTE_MARKS $HIGH_ROUTE_MARKS)
    TC_EXPERT=$(added_param_value_no TC_EXPERT $TC_EXPERT)
    [ -n "$XCONNMARK_MATCH" ] || XCONNMARK=
    [ -n "$XMARK" ] || XCONNMARK=

    [ -n "$HIGH_ROUTE_MARKS" -a -z "$XCONNMARK" ] && fatal_error "HIGH_ROUTE_MARKS=Yes requires extended CONNMARK target, extended CONNMARK match support and extended MARK support"

    case ${IPSECFILE:=ipsec} in
	ipsec|zones)
	    ;;
	*)
	    fatal_error "Invalid value ($IPSECFILE) for IPSECFILE option"
	    ;;
    esac

    case ${MACLIST_TABLE:=filter} in
	filter)
	    ;;
	mangle)
	    [ $MACLIST_DISPOSITION = reject ] && fatal_error "MACLIST_DISPOSITION=REJECT is not allowed with MACLIST_TABLE=mangle"
	    ;;	*)
	    fatal_error "Invalid value ($MACLIST_TABLE) for MACLIST_TABLE option"
	    ;;
    esac

   TC_SCRIPT=

   if [ -n "$TC_ENABLED" ] ; then
	case "$TC_ENABLED" in
	    [Yy][Ee][Ss])
		TC_ENABLED=
		TC_SCRIPT=$(find_file tcstart)
		[ -f $TC_SCRIPT ] || fatal_error "Unable to find tcstart file"
		;;
	    [Ii][Nn][Tt][Ee][Rr][Nn][Aa][Ll])
		TC_ENABLED=Yes
		;;
	    [Nn][Oo])
		TC_ENABLED=
		;;
	esac
    else
	TC_ENABLED=Yes
    fi

    if [ -n "$TC_ENABLED" ];then
	[ -n "$MANGLE_ENABLED" ] || fatal_error "Traffic Shaping requires mangle support in your kernel and iptables"
    fi

    [ "x${SHOREWALL_DIR}" = "x." ] && SHOREWALL_DIR="$PWD"
    [ -n "${RESTOREFILE:=restore}" ]

    #
    # Strip the files that we use often
    #
    strip_file interfaces
    strip_file hosts
    #
    # Check out the user's shell
    #
    [ -n "${SHOREWALL_SHELL:=/bin/sh}" ]

    temp=$(decodeaddr 192.168.1.1)
    if [ $(encodeaddr $temp) != 192.168.1.1 ]; then
	fatal_error "Shell $SHOREWALL_SHELL is broken and may not be used with Shorewall"
    fi

    if [ -z "$KLUDGEFREE" ]; then
	rm -f $TMP_DIR/physdev
	rm -f $TMP_DIR/iprange
    fi

    qt mywhich awk && HAVEAWK=Yes || HAVEAWK=
}

SHOREWALL_LIBRARY=Loaded