shorewall_code/Shorewall/firewall

#!/bin/sh
#
#     The Shoreline Firewall (Shorewall) Packet Filtering Firewall - V3.2
#
#     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)
#
#     tcstart from tc4shorewall       Version 0.5
#     (c) 2005 Arne Bernin <arne@ucbering.de>
#     Modified by Tom Eastep for integration into the Shorewall distribution
#     published under GPL Version 2#
#
#	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
#
#	If an error occurs while starting or restarting the firewall, the
#	firewall is automatically stopped.
#
#	Commands are:
#
#	   shorewall start			  Starts the firewall
#	   shorewall restart			  Restarts the firewall
#	   shorewall stop			  Stops the firewall
#	   shorewall reset			  Resets iptables packet and
#						  byte counts
#	   shorewall clear			  Remove all Shorewall chains
#						  and rules/policies.
#	   shorewall refresh	.		  Rebuild the common chain
#
# Mutual exclusion -- These functions are jackets for the mutual exclusion
#		      routines in $FUNCTIONS. They invoke
#		      the corresponding function in that file if the user did
#		      not specify "nolock" on the runline.
#
my_mutex_on() {
    [ -n "$NOLOCK" ] || { mutex_on; HAVE_MUTEX=Yes; }
}

my_mutex_off() {
    [ -n "$HAVE_MUTEX" ] && { mutex_off; HAVE_MUTEX=; }
}

#
# Fatal error -- stops the firewall after issuing the error message
#
fatal_error() # $* = Error Message
{
    echo "   ERROR: $@" >&2
    stop_firewall
    exit 2
}

#
# Fatal error during startup -- generate an error message and abend without
#				altering the state of the firewall
#
startup_error() # $* = Error Message
{
    echo "   ERROR: $@" >&2
    my_mutex_off
    [ -n "$TMP_DIR" ] && rm -rf $TMP_DIR
    [ -n "$RESTOREBASE" ] && rm -f $RESTOREBASE
    kill $$
    exit 2
}

#
# Send a message to STDOUT and the System Log
#
report () { # $* = message
    progress_message3 "$@"
    logger "$@"
}

#
# Run iptables and if an error occurs, stop the firewall and quit
#
run_iptables() {
    if [ -z "$KLUDGEFREE" ]; then
	#
	# Purge the temporary files that we use to prevent duplicate '-m' specifications
	#
	[ -n "$BRIDGING" ]      && [ -f $TMP_DIR/physdev ] && rm -f $TMP_DIR/physdev
	[ -n "$IPRANGE_MATCH" ] && [ -f $TMP_DIR/iprange ] && rm -f $TMP_DIR/iprange
    fi

   if ! $IPTABLES $@ ; then
	if [ -z "$STOPPING" ]; then
	    error_message "ERROR: Command \"$IPTABLES $@\" Failed"
	    stop_firewall
	    exit 2
	fi
    fi
}

#
# Version of 'run_iptables' that inserts white space after "!" in the arg list
#
run_iptables2() {

    case "$@" in
	*!*)
	    run_iptables $(fix_bang $@)
	    ;;
	*)
	    run_iptables $@
	    ;;
    esac

}

#
# Quietly run iptables
#
qt_iptables() {
    if [ -z "$KLUDGEFREE" ]; then
	#
	# Purge the temporary files that we use to prevent duplicate '-m' specifications
	#
	[ -n "$BRIDGING" ]      && [ -f $TMP_DIR/physdev ] && rm -f $TMP_DIR/physdev
	[ -n "$IPRANGE_MATCH" ] && [ -f $TMP_DIR/iprange ] && rm -f $TMP_DIR/iprange
    fi

    qt $IPTABLES $@
}

#
# Run ip and if an error occurs, stop the firewall and quit
#
run_ip() {
    if ! ip $@ ; then
	if [ -z "$STOPPING" ]; then
	    error_message "ERROR: Command \"ip $@\" Failed"
	    stop_firewall
	    exit 2
	fi
    fi
}

#
# Run tc and if an error occurs, stop the firewall and quit
#
run_tc() {
    if ! tc $@ ; then
	if [ -z "$STOPPING" ]; then
	    error_message "ERROR: Command \"tc $@\" Failed"
	    stop_firewall
	    exit 2
	fi
    fi
}

#
# Delete a chain if it exists
#
deletechain() # $1 = name of chain
{
    qt $IPTABLES -L $1 -n && qt $IPTABLES -F $1 && qt $IPTABLES -X $1
}

#
# 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)
		;;
	    *)
		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" ] || fatal_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"
}

#
# 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
}

#
# 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
    else
	echo -i $1
    fi
}

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

#
# 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
}

#
# 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 $option in
		-)
		    ;;
		dhcp|tcpflags|arp_filter|routefilter|maclist|logmartians|sourceroute|blacklist|proxyarp|nosmurfs|upnp|-)
		    ;;
		norfc1918)
		    addr=$(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
		    ;;
		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"
}

#
# Check that a mark value or mask is less that 256
#
verify_mark() # $1 = value to test
{
    verify_mark1()
    {
	[ $1 -lt 256 ]
    }

    verify_mark2()
    {
	verify_mark1 $1 2> /dev/null
    }

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

#
# 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 broadcast addresses -- if we are compiling a script and 'detect' is specified for an interface
#                             the function returns nothing for that interface
#
find_broadcasts() {
    for interface in $ALL_INTERFACES; do
	eval bcast=\$$(chain_base $interface)_broadcast
	if [ "x$bcast" = "xdetect" ]; then
	    ip -f inet addr show $interface 2> /dev/null | grep 'inet.*brd' | sed 's/inet.*brd //; s/scope.*//;' | sort -u
	elif [ "x${bcast}" != "x-" ]; then
	    echo $(separate_list $bcast)
	fi
    done
}

#
# 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#*:}
	run_iptables $1 INPUT  -i $interface $(source_ip_range $networks) -j ACCEPT
	[ -z "$ADMINISABSENTMINDED" -o $COMMAND != stop ] && \
	    run_iptables $1 OUTPUT -o $interface $(dest_ip_range $networks) -j ACCEPT

	matched=

	if list_search $host $source ; then
	    run_iptables $1 FORWARD -i $interface $(source_ip_range $networks) -j ACCEPT
	    matched=Yes
	fi

	if list_search $host $dest ; then
	    run_iptables $1 FORWARD -o $interface $(dest_ip_range $networks) -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=

    [ -f $TMP_DIR/routestopped ] || 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

}

#
# For each entry in the CRITICALHOSTS global list, add INPUT and OUTPUT rules to
# enable traffic to/from those hosts.
#
enable_critical_hosts()
{
    for host in $CRITICALHOSTS; do
	interface=${host%:*}
	networks=${host#*:}
	$IPTABLES -A INPUT  -i $interface $(source_ip_range $networks) -j ACCEPT
	$IPTABLES -A OUTPUT -o $interface $(dest_ip_range $networks) -j ACCEPT
    done
}

#
# For each entry in the CRITICALHOSTS global list, delete the INPUT and OUTPUT rules that
# enable traffic to/from those hosts.
#
disable_critical_hosts()
{
    for host in $CRITICALHOSTS; do
	interface=${host%:*}
	networks=${host#*:}
	$IPTABLES -D INPUT  -i $interface $(source_ip_range $networks) -j ACCEPT
	$IPTABLES -D OUTPUT -o $interface $(dest_ip_range $networks) -j ACCEPT
    done
}

#
# Stop the Firewall
#
stop_firewall() {
    #
    # Turn off trace unless we were tracing "stop" or "clear"
    #

    [ -n "$RESTOREBASE" ] && rm -f $RESTOREBASE

    case $COMMAND in
	stop|clear)
	    ;;
	*)
	    set +x

	    [ -n "${RESTOREFILE:=restore}" ]

	    RESTOREPATH=${VARDIR}/$RESTOREFILE

	    if [ -x $RESTOREPATH ]; then

		if [ -x ${RESTOREPATH}-ipsets ]; then
		    progress_message2 Restoring Ipsets...
		    #
		    # We must purge iptables to be sure that there are no
		    # references to ipsets
		    #
		    for table in mangle nat filter; do
			iptables -t $table -F
			iptables -t $table -X
		    done

		    ${RESTOREPATH}-ipsets
		fi

		echo Restoring Shorewall...

		if $RESTOREPATH restore; then
		    echo "Shorewall restored from $RESTOREPATH"
		    set_state "Started"
		else
		    set_state "Unknown"
		fi

		my_mutex_off
		kill $$
		exit 2
	    fi
	    ;;
    esac

    set_state "Stopping"

    STOPPING="Yes"

    TERMINATOR=

    deletechain shorewall

    run_user_exit stop

    if [ -n "$MANGLE_ENABLED" ]; then
	run_iptables -t mangle -F
	run_iptables -t mangle -X
	for chain in PREROUTING INPUT FORWARD POSTROUTING; do
	    qt $IPTABLES -t mangle -P $chain ACCEPT
	done
    fi

    if [ -n "$RAW_TABLE" ]; then
	run_iptables -t raw -F
	run_iptables -t raw -X
	for chain in PREROUTING OUTPUT; do
	    qt $IPTABLES -t raw -P $chain ACCEPT
	done
    fi

    if [ -n "$NAT_ENABLED" ]; then
	delete_nat
	for chain in PREROUTING POSTROUTING OUTPUT; do
	    qt $IPTABLES -t nat -P $chain ACCEPT
	done
    fi

    delete_proxy_arp
    [ -n "$CLEAR_TC" ] && delete_tc1

    [ -n "$DISABLE_IPV6" ] && disable_ipv6

    process_criticalhosts

    if [ -n "$CRITICALHOSTS" ]; then
	if [ -z "$ADMINISABSENTMINDED" ]; then
	    for chain in INPUT OUTPUT; do
		setpolicy $chain ACCEPT
	    done

	    setpolicy FORWARD DROP

	    deleteallchains

	    enable_critical_hosts

	    for chain in INPUT OUTPUT; do
		setpolicy $chain DROP
	    done
	else
	    for chain in INPUT OUTPUT; do
		setpolicy $chain ACCEPT
	    done

	    setpolicy FORWARD DROP

	    deleteallchains

	    enable_critical_hosts

	    setpolicy INPUT DROP

	    for chain in INPUT FORWARD; do
		setcontinue $chain
	    done
	fi
    elif [ -z "$ADMINISABSENTMINDED" ]; then
	for chain in INPUT OUTPUT FORWARD; do
	    setpolicy $chain DROP
	done

	deleteallchains
    else
	for chain in INPUT FORWARD; do
	    setpolicy $chain DROP
	done

	setpolicy OUTPUT ACCEPT

	deleteallchains

	for chain in INPUT FORWARD; do
	    setcontinue $chain
	done
    fi

    process_routestopped -A

    $IPTABLES -A INPUT  -i lo -j ACCEPT
    [ -z "$ADMINISABSENTMINDED" ] && \
	$IPTABLES -A OUTPUT -o lo -j ACCEPT

    for interface in $(find_interfaces_by_option dhcp); do
	$IPTABLES -A INPUT  -p udp -i $interface --dport 67:68 -j ACCEPT
	[ -z "$ADMINISABSENTMINDED" ] && \
	    $IPTABLES -A OUTPUT -p udp -o $interface --dport 67:68 -j ACCEPT
	#
	# This might be a bridge
	#
	$IPTABLES -A FORWARD -p udp -i $interface -o $interface --dport 67:68 -j ACCEPT
    done

    case "$IP_FORWARDING" in
    [Oo][Nn])
	echo 1 > /proc/sys/net/ipv4/ip_forward
	progress_message2 "IP Forwarding Enabled"
	;;
    [Oo][Ff][Ff])
	echo 0 > /proc/sys/net/ipv4/ip_forward
	progress_message2 "IP Forwarding Disabled!"
	;;
    esac

    run_user_exit stopped

    set_state "Stopped"

    logger "Shorewall Stopped"

    rm -rf $TMP_DIR

    case $COMMAND in
    stop|clear)
	;;
    *)
	#
	# The firewall is being stopped when we were trying to do something
	# else. Remove the lock file and Kill the shell in case we're in a
	# subshell
	#
	my_mutex_off
	kill $$
	;;
    esac
}

#
# Remove all rules and remove all user-defined chains
#
clear_firewall() {
    stop_firewall

    setpolicy INPUT ACCEPT
    setpolicy FORWARD ACCEPT
    setpolicy OUTPUT ACCEPT

    run_iptables -F

    echo 1 > /proc/sys/net/ipv4/ip_forward

    if [ -n "$DISABLE_IPV6" ] && qt mywhich ip6tables; then
	ip6tables -P INPUT   ACCEPT 2> /dev/null
	ip6tables -P OUTPUT  ACCEPT 2> /dev/null
	ip6tables -P FORWARD ACCEPT 2> /dev/null
    fi

    run_user_exit clear

    set_state "Cleared"

    logger "Shorewall Cleared"
}

#
# Delete existing Proxy ARP
#
delete_proxy_arp() {
    if [ -f ${VARDIR}/proxyarp ]; then
	while read address interface external haveroute; do
	    case $COMMAND in
		stop|clear)
		    qt arp -i $external -d $address pub
		    [ -z "${haveroute}${NOROUTES}" ] && qt ip route del $address dev $interface
		    ;;
		*)
		    if [ -n "$STOPPING" ]; then
			qt arp -i $external -d $address pub
			qt arp -i $external -d $address pub
			[ -z "${haveroute}${NOROUTES}" ] && qt ip route del $address dev $interface
		    else
			qt arp -i $external -d $address pub
			if [ -z "$haveroute" ];then
			    [ -n "$NOROUTE" ] || qt ip route del $address dev $interface
			fi
		    fi
		    ;;
	    esac
	done < ${VARDIR}/proxyarp

	rm -f ${VARDIR}/proxyarp
    fi

    [ -d ${VARDIR} ] && touch ${VARDIR}/proxyarp

    case $COMMAND in
	stop|clear)
	    for f in /proc/sys/net/ipv4/conf/*; do
		[ -f $f/proxy_arp ] && echo 0 > $f/proxy_arp
	    done
	    ;;
	*)
	    if [ -n "$STOPPING" ]; then
		for f in /proc/sys/net/ipv4/conf/*; do
		    [ -f $f/proxy_arp ] && echo 0 > $f/proxy_arp
		done
	    else
		for f in /proc/sys/net/ipv4/conf/*; do
		    [ -f $f/proxy_arp ] && echo 0 > $f/proxy_arp
		done
	    fi
	    ;;
    esac
}

#
# Delete existing Static NAT
#
delete_nat() {
    run_iptables -t nat -F
    run_iptables -t nat -X

    if [ -f ${VARDIR}/nat ]; then
	while read external interface; do
	    qt ip addr del $external dev $interface
	done < ${VARDIR}/nat

	rm -f ${VARDIR}/nat
    fi

    [ -d ${VARDIR} ] && touch ${VARDIR}/nat
}

#
# Setup ECN disabling rules
#
setup_ecn() # $1 = file name
{
    local interfaces=""
    local hosts=
    local h

    strip_file ecn $1

    progress_message2 "Processing $1..."

    while read interface host; do
	expandv interface host
	list_search  $interface $ALL_INTERFACES || \
	    startup_error "Unknown interface $interface"
	list_search $interface $interfaces || \
	    interfaces="$interfaces $interface"
	[ "x$host" = "x-" ] && host=
	for h in $(separate_list ${host:-0.0.0.0/0}); do
	    hosts="$hosts $interface:$h"
	done
    done < $TMP_DIR/ecn

    if [ -n "$interfaces" ]; then
	progress_message "Setting up ECN control on${interfaces}..."

	for interface in $interfaces; do
	    chain=$(ecn_chain $interface)
	    if havemanglechain $chain; then
		flushmangle $chain
	    else
		createmanglechain $chain
		run_iptables -t mangle -A POSTROUTING -p tcp -o $interface -j $chain
		run_iptables -t mangle -A OUTPUT      -p tcp -o $interface -j $chain
	    fi
	done

	for host in $hosts; do
	    interface=${host%:*}
	    h=${host#*:}
	    run_iptables -t mangle -A $(ecn_chain $interface) -p tcp $(dest_ip_range $h) -j ECN --ecn-tcp-remove
	    progress_message "   ECN Disabled to $h through $interface"
	done
    fi
}

# Display elements of a list with leading white space
#
display_list() # $1 = List Title, rest of $* = list to display
{
    [ $# -gt 1 ] && echo "   $*"
}

#
# Add a record to the blacklst chain
#
#   $source      = address match
#   $proto       = protocol selector
#   $dport       = destination port selector
#
add_blacklist_rule() {
    if [ -n "$BLACKLIST_LOGLEVEL" ]; then
	log_rule $BLACKLIST_LOGLEVEL blacklst $BLACKLIST_DISPOSITION  $(fix_bang $source $proto $dport)
    fi

    run_iptables2 -A blacklst $source $proto $dport -j $disposition
}

#
# Process a record from the blacklist file
#
#   $networks	 = address/networks
#   $protocol    = Protocol Number/Name
#   $port        = Port Number/Name
#
process_blacklist_rec() {
    local source
    local addr
    local proto
    local dport
    local temp
    local setname

    for addr in $(separate_list $networks); do
	case $addr in
	    -)
		source=
		;;
	    ~*)
		addr=$(echo $addr | sed 's/~//;s/-/:/g')
		source="--match mac --mac-source $addr"
		;;
	    *)
		source="$(source_ip_range $addr)"
		;;
	esac

	if [ -n "$protocol" ]; then
	    proto=" -p $protocol "

	    case $protocol in
		tcp|TCP|6|udp|UDP|17)
		    if [ -n "$ports" ]; then
			if [ -n "$MULTIPORT" -a \
			    "$ports" != "${ports%,*}" -a \
			    "$ports" = "${ports%:*}" -a \
			    $(list_count $ports) -le 15 ]
			then
			    dport="-m multiport --dports $ports"
			    add_blacklist_rule
			else
			    for dport in $(separate_list $ports); do
				dport="--dport $dport"
				add_blacklist_rule
			    done
			fi
		    else
			add_blacklist_rule
		    fi
		    ;;
		icmp|ICMP|0)
		    if [ -n "$ports" ]; then
			for dport in $(separate_list $ports); do
			    dport="--icmp-type $dport"
			    add_blacklist_rule
			done
		    else
			add_blacklist_rule
		    fi
		    ;;
		*)
		    add_blacklist_rule
		    ;;
	    esac
	else
	    add_blacklist_rule
	fi

	if [ -n "$ports" ]; then
	    addr="$addr $protocol $ports"
	elif [ -n "$protocol" ]; then
	    addr="$addr $protocol"
	fi

	progress_message "   $addr added to Black List"
    done
}

#
# Refresh the Black List
#
refresh_blacklist() {
    local f=$(find_file blacklist)
    local disposition=$BLACKLIST_DISPOSITION

    if qt $IPTABLES -L blacklst -n ; then
	progress_message2 "Loading Black List..."

	strip_file blacklist $f

	[ "$disposition" = REJECT ] && disposition=reject

	run_iptables -F blacklst

	while read networks protocol ports; do
	    expandv networks protocol ports
	    process_blacklist_rec
	done < $TMP_DIR/blacklist
    fi
}

#
# Verify the Black List
#
validate_blacklist() {
    local f=$(find_file blacklist)
    local disposition=$BLACKLIST_DISPOSITION

    progress_message2 "Checking Black List..."

    strip_file blacklist $f

    [ "$disposition" = REJECT ] && disposition=reject

    while read networks protocol ports; do
	expandv networks protocol ports
	process_blacklist_rec
    done < $TMP_DIR/blacklist
}

#
# Verify that kernel has netfilter support
#
verify_os_version() {

    osversion=$(uname -r)

    case $osversion in
    2.4.*|2.5.*|2.6.*)
	;;
    *)
	startup_error "Shorewall version $VERSION does not work with kernel version $osversion"
	;;
    esac

    [ $COMMAND = start -a -n "$(lsmod 2> /dev/null | grep '^ipchains')" ] && \
	startup_error "Shorewall can't start with the ipchains kernel module loaded - see FAQ #8"
}

#
# Check for disabled startup
#
check_disabled_startup() {
    if [ -z "$STARTUP_ENABLED" ]; then
	echo "   Shorewall Startup is disabled -- to enable startup"
	echo "   after you have completed Shorewall configuration,"
	echo "   change the setting of STARTUP_ENABLED to Yes in"
        echo "   ${CONFDIR}/shorewall.conf"

	[ -n "$TMP_DIR" ] && rm -rf $TMP_DIR
	my_mutex_off
	exit 2
    fi
}

#
# Refresh queuing and classes
#
refresh_tc() {
    #
    # tc4shorewall (setup_traffic_shaping()) uses this function to report progress
    #
    progress_message_and_save()
    {
	progress_message $@
    }

    echo "Refreshing Traffic Control Rules..."

    [ -n "$CLEAR_TC" ] && delete_tc1

    [ -n "$MARK_IN_FORWARD_CHAIN" ] && chain=tcfor || chain=tcpre

    #
    # Flush the TC mangle chains
    #

    if [ -n "$MANGLE_FORWARD" ]; then
	run_iptables -t mangle -F tcfor
	run_iptables -t mangle -F tcpost
    fi

    run_iptables -t mangle -F tcpre
    run_iptables -t mangle -F tcout
    #
    # Remove all exclusion chains from the mangle table
    #
    $IPTABLES -t mangle -L -n | grep '^Chain excl_' | while read junk chain rest; do
	run_iptables -t mangle -F $chain
	run_iptables -t mangle -X $chain
    done

    #
    # Process the TC Rules File
    #
    strip_file tcrules

    while read mark sources dests proto ports sports user testval; do
	expandv mark sources dests proto ports sports user testval tos
	rule=$(echo "$mark $sources $dests $proto $ports $sports $user $testval $tos")
	process_tc_rule
    done < $TMP_DIR/tcrules

    if [ -n "$TC_SCRIPT" ]; then
	run_user_exit $TC_SCRIPT
    elif [ -n "$TC_ENABLED" ]; then
	setup_traffic_shaping
    fi

}

#
# Refresh the firewall
#
refresh_firewall()
{
    DOING=Refreshing
    DONE=Refreshed

    progress_message3 "Refreshing Shorewall..."

    progress_message2 "Determining Zones and Interfaces..."

    determine_zones

    validate_interfaces_file

    determine_interfaces

    run_user_exit refresh

    #
    # Blacklist
    #
    refresh_blacklist

    ecn=$(find_file ecn)

    [ -f $ecn ] && [ -n "$MANGLE_ENABLED" ] && setup_ecn $ecn

    #
    # Refresh Traffic Control
    #
    [ -n "$MANGLE_ENABLED" ] && refresh_tc

    run_user_exit refreshed

    report "Shorewall Refreshed"

    rm -rf $TMP_DIR
}

#
# 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=startup_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=
    FUNCTIONS=
    VERSION_FILE=
    LOGFORMAT=
    LOGRULENUMBERS=
    ADMINISABSENTMINDED=
    BLACKLISTNEWONLY=
    MODULE_SUFFIX=
    ACTIONS=
    USEDACTIONS=
    SMURF_LOG_LEVEL=
    DISABLE_IPV6=
    BRIDGING=
    PKTTYPE=
    USEPKTYPE=
    RETAIN_ALIASES=
    DELAYBLACKLISTLOAD=
    LOGTAGONLY=
    LOGALLNEW=
    RFC1918_STRICT=
    MACLIST_TTL=
    SAVE_IPSETS=
    RESTOREFILE=
    MAPOLDACTIONS=
    IMPLICIT_CONTINUE=

    RESTOREBASE=
    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=

    SHAREDIR=/usr/share/shorewall
    VARDIR=/var/lib/shorewall
    CONFDIR=/etc/shorewall
    
    FUNCTIONS=${SHAREDIR}/functions

    if [ -f $FUNCTIONS ]; then
	[ $VERBOSE -gt 1 ] && echo "Loading $FUNCTIONS..."
	. $FUNCTIONS
    else
	startup_error "$FUNCTIONS does not exist!"
    fi

    TMP_DIR=$(mktempdir)

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

    trap "[ -n "$RESTOREBASE" ] && rm -f $RESTOREBASE;rm -rf $TMP_DIR; my_mutex_off; exit 2" 1 2 3 4 5 6 9

    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
	    startup_error "Cannot read $config (Hint: Are you root?)"
	fi
    else
	startup_error "$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" ]; then

	load_kernel_modules

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

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

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

    else
	f=$(find_file capabilities)

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

    ALLOWRELATED="$(added_param_value_yes ALLOWRELATED $ALLOWRELATED)"
    [ -n "$ALLOWRELATED" ] || \
	startup_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])
	    ;;
	*)
	    startup_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" ] && \
	startup_error "FORWARDPING=Yes is no longer supported"

    maclist_target=reject

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

    if [ -n "$TCP_FLAGS_DISPOSITION" ] ; then
	case $TCP_FLAGS_DISPOSITION in
	    REJECT|ACCEPT|DROP)
		;;
	    *)
		startup_error "Invalid value ($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 [ $? -ne 0 ]; then
		startup_error "Invalid LOGFORMAT string: \"$LOGFORMAT\""
	    fi
	else
	    temp=$(printf "$LOGFORMAT" fooxx barxx 2> /dev/null)
	    if [ $? -ne 0 ]; then
		startup_error "Invalid LOGFORMAT string: \"$LOGFORMAT\""
	    fi
	fi

	[ ${#temp} -le 29 ] || startup_error "LOGFORMAT string is longer than 29 characters: \"$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 $BRIDGING)
    STARTUP_ENABLED=$(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 $HIGH_ROUTE_MARKS)
    [ -n "$XCONNMARK_MATCH" ] || XCONNMARK=
    [ -n "$XMARK" ] || XCONNMARK=

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

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

    case ${MACLIST_TABLE:=filter} in
	filter)
	    ;;
	mangle)
	    [ $MACLIST_DISPOSITION = reject ] && startup_error "MACLIST_DISPOSITION=REJECT is not allowed with MACLIST_TABLE=mangle"
	    ;;	*)
	    startup_error "Invalid value ($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 ] || startup_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" ] || startup_error "Traffic Shaping requires mangle support in your kernel and iptables"
    fi

    [ "x${SHOREWALL_DIR}" = "x." ] && SHOREWALL_DIR="$PWD"

    #
    # 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
	startup_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

}

#
# Give Usage Information
#
usage() {
    echo "Usage: $0 [debug] {start|stop|reset|restart|refresh|clear}"
    exit 1
}

#
# E X E C U T I O N    B E G I N S   H E R E
#
#
# Start trace if first arg is "debug"
#
[ $# -gt 1 ] && [ "$1" = "debug" ] && { set -x ; shift ; }

NOLOCK=

[ $# -gt 1 ] && [ "$1" = "nolock" ] && { NOLOCK=Yes; shift ; }

trap "my_mutex_off; exit 2" 1 2 3 4 5 6 9

COMMAND="$1"

case "$COMMAND" in
    stop)
	[ $# -ne 1 ] && usage
	do_initialize
	my_mutex_on
	#
	# Don't want to do a 'stop' when startup is disabled
	#
	check_disabled_startup
	progress_message3 "Stopping Shorewall..."
	stop_firewall
	[ -n "$SUBSYSLOCK" ] && rm -f $SUBSYSLOCK
	progress_message3 "done."
	my_mutex_off
	;;

    reset)
	[ $# -ne 1 ] && usage
	do_initialize
	my_mutex_on
	if ! shorewall_is_started ; then
	    echo "Shorewall Not Started"
	    [ -n "$TMP_DIR" ] && rm -rf $TMP_DIR
	    my_mutex_off
	    exit 2;
	fi
	$IPTABLES -Z
	$IPTABLES -t nat -Z
	$IPTABLES -t mangle -Z
	report "Shorewall Counters Reset"
	date > ${VARDIR}/restarted
	my_mutex_off
	;;

    refresh)
	[ $# -ne 1 ] && usage
	do_initialize
	my_mutex_on
	if ! shorewall_is_started ; then
	    echo "Shorewall Not Started" >&2
	    [ -n "$TMP_DIR" ] && rm -rf $TMP_DIR
	    my_mutex_off
	    exit 2;
	fi
	refresh_firewall;
	my_mutex_off
	;;

    clear)
	[ $# -ne 1 ] && usage
	do_initialize
	my_mutex_on
	progress_message3 "Clearing Shorewall..."
	clear_firewall
	[ -n "$SUBSYSLOCK" ] && rm -f $SUBSYSLOCK
	progress_message3 "done."
	my_mutex_off
	;;

   call)
	#
	# Undocumented way to call functions in ${SHAREDIR}/firewall directly
	#
	shift
	do_initialize
	EMPTY=
	$@
	;;

    *)
	usage
	;;

esac