freebsd-nq/release/picobsd/floppy.tree/etc/rc.firewall

# $FreeBSD$

# Setup system for firewall service, with some sample configurations.
# Select one using ${firewall_type} which you can set in /etc/rc.conf.local.
#
# If you override this file with your own copy, you can use ${hostname}
# as the key for the case statement. On entry, the firewall will be flushed
# and $fwcmd will point to the appropriate command (usually /sbin/ipfw)
#
# Sample configurations are:
#   open     - will allow anyone in
#   client   - will try to protect just this machine (should be customized).
#   simple   - will try to protect a whole network (should be customized).
#   closed   - totally disables IP services except via lo0 interface
#   UNKNOWN  - disables the loading of firewall rules.
#   filename - will load the rules in the given filename (full path required)
#

############
# Only in rare cases do you want to change these rules
$fwcmd add 1000 pass all from any to any via lo0
$fwcmd add 1010 deny all from 127.0.0.0/8 to 127.0.0.0/8


# Prototype setups.
case "${firewall_type}" in
open|OPEN)
    $fwcmd add 65000 pass all from any to any
    ;;

client)

    ############
    # This is a prototype setup that will protect your system somewhat against
    # people from outside your own network.
    ############

    # set these to your network and netmask and ip
    net="192.168.4.0"
    mask="255.255.255.0"
    ip="192.168.4.17"

    # Allow any traffic to or from my own net.
    $fwcmd add pass all from ${ip} to ${net}:${mask}
    $fwcmd add pass all from ${net}:${mask} to ${ip}

    # Allow TCP through if setup succeeded
    $fwcmd add pass tcp from any to any established

    # Allow setup of incoming email 
    $fwcmd add pass tcp from any to ${ip} 25 setup

    # Allow setup of outgoing TCP connections only
    $fwcmd add pass tcp from ${ip} to any setup

    # Disallow setup of all other TCP connections
    $fwcmd add deny tcp from any to any setup

    # Allow DNS queries out in the world
    $fwcmd add pass udp from any 53 to ${ip}
    $fwcmd add pass udp from ${ip} to any 53

    # Allow NTP queries out in the world
    $fwcmd add pass udp from any 123 to ${ip}
    $fwcmd add pass udp from ${ip} to any 123

    # Everything else is denied as default.
    $fwcmd add 65000 deny all from any to any
    ;;

simple)

    ############
    # This is a prototype setup for a simple firewall.  Configure this machine 
    # as a named server and ntp server, and point all the machines on the inside
    # at this machine for those services.
    ############

    # set these to your outside interface network and netmask and ip
    oif="ed0"
    onet="192.168.4.0"
    omask="255.255.255.0"
    oip="192.168.4.17"

    # set these to your inside interface network and netmask and ip
    iif="ed1"
    inet="192.168.3.0"
    imask="255.255.255.0"
    iip="192.168.3.17"

    # Stop spoofing
    $fwcmd add deny all from ${inet}:${imask} to any in via ${oif}
    $fwcmd add deny all from ${onet}:${omask} to any in via ${iif}

    # Stop RFC1918 nets on the outside interface
    $fwcmd add deny all from 192.168.0.0:255.255.0.0 to any via ${oif}
    $fwcmd add deny all from 172.16.0.0:255.240.0.0 to any via ${oif}
    $fwcmd add deny all from 10.0.0.0:255.0.0.0 to any via ${oif}

    # Allow TCP through if setup succeeded
    $fwcmd add pass tcp from any to any established

    # Allow setup of incoming email 
    $fwcmd add pass tcp from any to ${oip} 25 setup

    # Allow access to our DNS
    $fwcmd add pass tcp from any to ${oip} 53 setup

    # Allow access to our WWW
    $fwcmd add pass tcp from any to ${oip} 80 setup

    # Reject&Log all setup of incoming connections from the outside
    $fwcmd add deny log tcp from any to any in via ${oif} setup

    # Allow setup of any other TCP connection
    $fwcmd add pass tcp from any to any setup

    # Allow DNS queries out in the world
    $fwcmd add pass udp from any 53 to ${oip}
    $fwcmd add pass udp from ${oip} to any 53

    # Allow NTP queries out in the world
    $fwcmd add pass udp from any 123 to ${oip}
    $fwcmd add pass udp from ${oip} to any 123

    # Everything else is denied as default.
    $fwcmd add 65000 deny all from any to any
    ;;

UNKNOWN|"")
    echo "WARNING: firewall rules not loaded."
    ;;

*)  # an absolute pathname ?
    if [ -f "${firewall_type}" ] ; then
	$fwcmd ${firewall_type}
    else
	echo "WARNING: firewall config script (${firewall_type}) not found,"
	echo "         firewall rules not loaded."
    fi
    ;;
esac