#!/bin/bash

#

# iptables	Start iptables firewall

#

# chkconfig: 2345 08 92

# description:	Starts, stops and saves iptables firewall

#

# config: /etc/sysconfig/iptables

# config: /etc/sysconfig/iptables-config

#

### BEGIN INIT INFO

# Provides: iptables

# Required-Start:

# Required-Stop:

# Default-Start: 2 3 4 5

# Default-Stop: 0 1 6

# Short-Description: start and stop iptables firewall

# Description: Start, stop and save iptables firewall

### END INIT INFO

# Source function library.

. /etc/init.d/functions

IPTABLES=iptables

IPTABLES_DATA=/etc/sysconfig/$IPTABLES

IPTABLES_FALLBACK_DATA=${IPTABLES_DATA}.fallback

IPTABLES_CONFIG=/etc/sysconfig/${IPTABLES}-config

IPV=${IPTABLES%tables} # ip for ipv4 | ip6 for ipv6

[ "$IPV" = "ip" ] && _IPV="ipv4" || _IPV="ipv6"

PROC_IPTABLES_NAMES=/proc/net/${IPV}_tables_names

VAR_SUBSYS_IPTABLES=/var/lock/subsys/$IPTABLES

RESTORECON=/bin/restorecon

[ ! -x "$RESTORECON" ] && RESTORECON=/bin/true

# only usable for root

if [ $EUID != 0 ]; then

    echo -n $"${IPTABLES}: Only usable by root."; warning; echo

    exit 4

fi

if [ ! -x /sbin/$IPTABLES ]; then

    echo -n $"${IPTABLES}: /sbin/$IPTABLES does not exist."; warning; echo

    exit 5

fi

# Old or new modutils

/sbin/modprobe --version 2>&1 | grep -q 'kmod version' \

    && NEW_MODUTILS=1 \

    || NEW_MODUTILS=0

# Default firewall configuration:

IPTABLES_MODULES=""

IPTABLES_MODULES_UNLOAD="yes"

IPTABLES_SAVE_ON_STOP="no"

IPTABLES_SAVE_ON_RESTART="no"

IPTABLES_SAVE_COUNTER="no"

IPTABLES_STATUS_NUMERIC="yes"

IPTABLES_STATUS_VERBOSE="no"

IPTABLES_STATUS_LINENUMBERS="yes"

IPTABLES_SYSCTL_LOAD_LIST=""

IPTABLES_RESTORE_WAIT=600

IPTABLES_RESTORE_WAIT_INTERVAL=1000000

# Load firewall configuration.

[ -f "$IPTABLES_CONFIG" ] && . "$IPTABLES_CONFIG"

# Netfilter modules

NF_MODULES=($(lsmod | awk "/^${IPV}table_/ {print \$1}") ${IPV}_tables)

NF_MODULES_COMMON=(x_tables nf_nat nf_conntrack) # Used by netfilter v4 and v6

# Get active tables

NF_TABLES=$(cat "$PROC_IPTABLES_NAMES" 2>/dev/null)

rmmod_r() {

    # Unload module with all referring modules.

    # At first all referring modules will be unloaded, then the module itself.

    local mod=$1

    local ret=0

    local ref=

    # Get referring modules.

    # New modutils have another output format.

    [ $NEW_MODUTILS = 1 ] \

	&& ref=$(lsmod | awk "/^${mod}/ { print \$4; }" | tr ',' ' ') \

	|| ref=$(lsmod | grep ^${mod} | cut -d "[" -s -f 2 | cut -d "]" -s -f 1)

    # recursive call for all referring modules

    for i in $ref; do

	rmmod_r $i

	let ret+=$?;

    done

    # Unload module.

    # The extra test is for 2.6: The module might have autocleaned,

    # after all referring modules are unloaded.

    if grep -q "^${mod}" /proc/modules ; then

	modprobe -r $mod > /dev/null 2>&1

	res=$?

	[ $res -eq 0 ] || echo -n " $mod"

	let ret+=$res;

    fi

    return $ret

}

flush_n_delete() {

    # Flush firewall rules and delete chains.

    [ ! -e "$PROC_IPTABLES_NAMES" ] && return 0

    # Check if firewall is configured (has tables)

    [ -z "$NF_TABLES" ] && return 1

    echo -n $"${IPTABLES}: Flushing firewall rules: "

    ret=0

    # For all tables

    for i in $NF_TABLES; do

        # Flush firewall rules.

	$IPTABLES -t $i -F;

	let ret+=$?;

        # Delete firewall chains.

	$IPTABLES -t $i -X;

	let ret+=$?;

	# Set counter to zero.

	$IPTABLES -t $i -Z;

	let ret+=$?;

    done

    [ $ret -eq 0 ] && success || failure

    echo

    return $ret

}

set_policy() {

    # Set policy for configured tables.

    policy=$1

    # Check if iptable module is loaded

    [ ! -e "$PROC_IPTABLES_NAMES" ] && return 0

    # Check if firewall is configured (has tables)

    tables=$(cat "$PROC_IPTABLES_NAMES" 2>/dev/null)

    [ -z "$tables" ] && return 1

    echo -n $"${IPTABLES}: Setting chains to policy $policy: "

    ret=0

    for i in $tables; do

	echo -n "$i "

	case "$i" in

	    raw)

		$IPTABLES -t raw -P PREROUTING $policy \

		    && $IPTABLES -t raw -P OUTPUT $policy \

		    || let ret+=1

		;;

	    filter)

                $IPTABLES -t filter -P INPUT $policy \

		    && $IPTABLES -t filter -P OUTPUT $policy \

		    && $IPTABLES -t filter -P FORWARD $policy \

		    || let ret+=1

		;;

	    nat)

		$IPTABLES -t nat -P PREROUTING $policy \

		    && $IPTABLES -t nat -P POSTROUTING $policy \

		    && $IPTABLES -t nat -P OUTPUT $policy \

		    || let ret+=1

		;;

	    mangle)

	        $IPTABLES -t mangle -P PREROUTING $policy \

		    && $IPTABLES -t mangle -P POSTROUTING $policy \

		    && $IPTABLES -t mangle -P INPUT $policy \

		    && $IPTABLES -t mangle -P OUTPUT $policy \

		    && $IPTABLES -t mangle -P FORWARD $policy \

		    || let ret+=1

		;;

	    *)

	        let ret+=1

		;;

        esac

    done

    [ $ret -eq 0 ] && success || failure

    echo

    return $ret

}

load_sysctl() {

    # load matched sysctl values

    if [ -n "$IPTABLES_SYSCTL_LOAD_LIST" ]; then

        echo -n $"Loading sysctl settings: "

        ret=0

        for item in $IPTABLES_SYSCTL_LOAD_LIST; do

            fgrep $item /etc/sysctl.conf | sysctl -p - >/dev/null

            let ret+=$?;

        done

        [ $ret -eq 0 ] && success || failure

        echo

    fi

    return $ret

}

start() {

    # Do not start if there is no config file.

    if [ ! -f "$IPTABLES_DATA" ]; then

	echo -n $"${IPTABLES}: No config file."; warning; echo

	return 6

    fi

    # check if ipv6 module load is deactivated

    if [ "${_IPV}" = "ipv6" ] \

	&& grep -qIsE "^install[[:space:]]+${_IPV}[[:space:]]+/bin/(true|false)" /etc/modprobe.conf /etc/modprobe.d/* ; then

	echo $"${IPTABLES}: ${_IPV} is disabled."

	return 150

    fi

    echo -n $"${IPTABLES}: Applying firewall rules: "

    OPT=

    [ "x$IPTABLES_SAVE_COUNTER" = "xyes" ] && OPT="-c"

    if [ $IPTABLES_RESTORE_WAIT -ne 0 ]; then

	OPT="${OPT} --wait ${IPTABLES_RESTORE_WAIT}"

	if [ $IPTABLES_RESTORE_WAIT_INTERVAL -lt 1000000 ]; then

	    OPT="${OPT} --wait-interval ${IPTABLES_RESTORE_WAIT_INTERVAL}"

	fi

    fi

    $IPTABLES-restore $OPT $IPTABLES_DATA

    if [ $? -eq 0 ]; then

	success; echo

    else

	failure; echo;

	if [ -f "$IPTABLES_FALLBACK_DATA" ]; then

	    echo -n $"${IPTABLES}: Applying firewall fallback rules: "

	    $IPTABLES-restore $OPT $IPTABLES_FALLBACK_DATA

	    if [ $? -eq 0 ]; then

		success; echo

	    else

		failure; echo; return 1

	    fi

	else

	    return 1

	fi

    fi

    # Load additional modules (helpers)

    if [ -n "$IPTABLES_MODULES" ]; then

	echo -n $"${IPTABLES}: Loading additional modules: "

	ret=0

	for mod in $IPTABLES_MODULES; do

	    echo -n "$mod "

	    modprobe $mod > /dev/null 2>&1

	    let ret+=$?;

	done

	[ $ret -eq 0 ] && success || failure

	echo

    fi

    # Load sysctl settings

    load_sysctl

    touch $VAR_SUBSYS_IPTABLES

    return $ret

}

stop() {

    # Do not stop if iptables module is not loaded.

    [ ! -e "$PROC_IPTABLES_NAMES" ] && return 0

    # Set default chain policy to ACCEPT, in order to not break shutdown

    # on systems where the default policy is DROP and root device is

    # network-based (i.e.: iSCSI, NFS)

    set_policy ACCEPT

    # And then, flush the rules and delete chains

    flush_n_delete

    if [ "x$IPTABLES_MODULES_UNLOAD" = "xyes" ]; then

	echo -n $"${IPTABLES}: Unloading modules: "

	ret=0

	for mod in ${NF_MODULES[*]}; do

	    rmmod_r $mod

	    let ret+=$?;

	done

	# try to unload remaining netfilter modules used by ipv4 and ipv6 

	# netfilter

	for mod in ${NF_MODULES_COMMON[*]}; do

	    rmmod_r $mod >/dev/null

	done

	[ $ret -eq 0 ] && success || failure

	echo

    fi

    rm -f $VAR_SUBSYS_IPTABLES

    return $ret

}

save() {

    # Check if iptable module is loaded

    if [ ! -e "$PROC_IPTABLES_NAMES" ]; then

	echo -n $"${IPTABLES}: Nothing to save."; warning; echo

	return 0

    fi

    # Check if firewall is configured (has tables)

    if [ -z "$NF_TABLES" ]; then

	echo -n $"${IPTABLES}: Nothing to save."; warning; echo

	return 6

    fi

    echo -n $"${IPTABLES}: Saving firewall rules to $IPTABLES_DATA: "

    OPT=

    [ "x$IPTABLES_SAVE_COUNTER" = "xyes" ] && OPT="-c"

    ret=0

    TMP_FILE=$(/bin/mktemp -q $IPTABLES_DATA.XXXXXX) \

	&& chmod 600 "$TMP_FILE" \

	&& $IPTABLES-save $OPT > $TMP_FILE 2>/dev/null \

	&& size=$(stat -c '%s' $TMP_FILE) && [ $size -gt 0 ] \

	|| ret=1

    if [ $ret -eq 0 ]; then

	if [ -e $IPTABLES_DATA ]; then

	    cp -f $IPTABLES_DATA $IPTABLES_DATA.save \

		&& chmod 600 $IPTABLES_DATA.save \

		&& $RESTORECON $IPTABLES_DATA.save \

		|| ret=1

	fi

	if [ $ret -eq 0 ]; then

	    mv -f $TMP_FILE $IPTABLES_DATA \

		&& chmod 600 $IPTABLES_DATA \

		&& $RESTORECON $IPTABLES_DATA \

	        || ret=1

	fi

    fi

    rm -f $TMP_FILE

    [ $ret -eq 0 ] && success || failure

    echo

    return $ret

}

status() {

    if [ ! -f "$VAR_SUBSYS_IPTABLES" -a -z "$NF_TABLES" ]; then

	echo $"${IPTABLES}: Firewall is not running."

	return 3

    fi

    # Do not print status if lockfile is missing and iptables modules are not 

    # loaded.

    # Check if iptable modules are loaded

    if [ ! -e "$PROC_IPTABLES_NAMES" ]; then

	echo $"${IPTABLES}: Firewall modules are not loaded."

	return 3

    fi

    # Check if firewall is configured (has tables)

    if [ -z "$NF_TABLES" ]; then

	echo $"${IPTABLES}: Firewall is not configured. "

	return 3

    fi

    NUM=

    [ "x$IPTABLES_STATUS_NUMERIC" = "xyes" ] && NUM="-n"

    VERBOSE= 

    [ "x$IPTABLES_STATUS_VERBOSE" = "xyes" ] && VERBOSE="--verbose"

    COUNT=

    [ "x$IPTABLES_STATUS_LINENUMBERS" = "xyes" ] && COUNT="--line-numbers"

    for table in $NF_TABLES; do

	echo $"Table: $table"

	$IPTABLES -t $table --list $NUM $VERBOSE $COUNT && echo

    done

    return 0

}

reload() {

    # Do not reload if there is no config file.

    if [ ! -f "$IPTABLES_DATA" ]; then

	echo -n $"${IPTABLES}: No config file."; warning; echo

	return 6

    fi

    # check if ipv6 module load is deactivated

    if [ "${_IPV}" = "ipv6" ] \

	&& grep -qIsE "^install[[:space:]]+${_IPV}[[:space:]]+/bin/(true|false)" /etc/modprobe.conf /etc/modprobe.d/* ; then

	echo $"${IPTABLES}: ${_IPV} is disabled."

	return 150

    fi

    echo -n $"${IPTABLES}: Trying to reload firewall rules: "

    OPT=

    [ "x$IPTABLES_SAVE_COUNTER" = "xyes" ] && OPT="-c"

    if [ $IPTABLES_RESTORE_WAIT -ne 0 ]; then

	OPT="${OPT} --wait ${IPTABLES_RESTORE_WAIT}"

	if [ $IPTABLES_RESTORE_WAIT_INTERVAL -lt 1000000 ]; then

	    OPT="${OPT} --wait-interval ${IPTABLES_RESTORE_WAIT_INTERVAL}"

	fi

    fi

    $IPTABLES-restore $OPT $IPTABLES_DATA

    if [ $? -eq 0 ]; then

	success; echo

    else

	failure; echo; echo "Firewall rules are not changed."; return 1

    fi

    # Load additional modules (helpers)

    if [ -n "$IPTABLES_MODULES" ]; then

	echo -n $"${IPTABLES}: Loading additional modules: "

	ret=0

	for mod in $IPTABLES_MODULES; do

	    echo -n "$mod "

	    modprobe $mod > /dev/null 2>&1

	    let ret+=$?;

	done

	[ $ret -eq 0 ] && success || failure

	echo

    fi

    # Load sysctl settings

    load_sysctl

    return $ret

}

restart() {

    [ "x$IPTABLES_SAVE_ON_RESTART" = "xyes" ] && save

    stop

    start

}

case "$1" in

    start)

	[ -f "$VAR_SUBSYS_IPTABLES" ] && exit 0

	start

	RETVAL=$?

	;;

    stop)

	[ "x$IPTABLES_SAVE_ON_STOP" = "xyes" ] && save

	stop

	RETVAL=$?

	;;

    restart|force-reload)

	restart

	RETVAL=$?

	;;

    reload)

	[ -e "$VAR_SUBSYS_IPTABLES" ] && reload

	RETVAL=$?

	;;      

    condrestart|try-restart)

	[ ! -e "$VAR_SUBSYS_IPTABLES" ] && exit 0

	restart

	RETVAL=$?

	;;

    status)

	status

	RETVAL=$?

	;;

    panic)

	set_policy DROP

	RETVAL=$?

        ;;

    save)

	save

	RETVAL=$?

	;;

    *)

	echo $"Usage: ${IPTABLES} {start|stop|reload|restart|condrestart|status|panic|save}"

	RETVAL=2

	;;

esac

exit $RETVAL