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Date:      Tue, 17 Jul 2001 22:01:20 +0100
From:      Vasily <vasily@maryno.net>
To:        freebsd-questions@FreeBSD.ORG
Subject:   Question about ipfw
Message-ID:  <4917.010717@maryno.net>

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Hi, ALL !

Would anybody be so kind to tell where is saved information about
lines marked * ?
In rc.conf name of type of firewall is "UNKNOWN".

boss# ipfw list

00001 allow tcp from any to *.*.*.* 80 in recv ed1
00002 allow tcp from *.*.*.* to *.*.*.* 20,21 in recv ed1
00003 allow tcp from *.*.*.* to *.*.*.* 22 in recv ed1
00004 allow udp from any to any 53
00005 allow tcp from 192.168.1.0 to any 20,21,22,139 in recv ed1
*00050 divert 8668 ip from any to any via ed1
00051 reset tcp from any to *.*.*.* 1-1024 in recv ed1
00052 deny udp from any to any 1-1024 in recv ed1
00053 unreach port tcp from any to 212.42.60.107 1025-65535 in setup
00100 allow ip from any to any via lo0
00200 deny ip from any to 127.0.0.0/8
*00300 divert 8668 ip from 192.168.1.0 to any out xmit ed1
*00400 divert 8668 ip from any to *.*.*.* in recv ed1
*65535 allow ip from any to any

It's rc.firewall
=========================================
############
# Setup system for firewall service.
# $FreeBSD: src/etc/rc.firewall,v 1.30.2.4 2000/05/28 19:17:15 asmodai Exp $

# Suck in the configuration variables.
if [ -r /etc/defaults/rc.conf ]; then
        . /etc/defaults/rc.conf
        source_rc_confs
elif [ -r /etc/rc.conf ]; then
        . /etc/rc.conf
fi

############
# Define the firewall type in /etc/rc.conf.  Valid values are:
#   open     - will allow anyone in
#   client   - will try to protect just this machine
#   simple   - will try to protect a whole network
#   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)
#
# For ``client'' and ``simple'' the entries below should be customized
# appropriately.

############
#
# If you don't know enough about packet filtering, we suggest that you
# take time to read this book:
#
#       Building Internet Firewalls
#       Brent Chapman and Elizabeth Zwicky
#
#       O'Reilly & Associates, Inc
#       ISBN 1-56592-124-0
#       http://www.ora.com/
#
# For a more advanced treatment of Internet Security read:
#
#       Firewalls & Internet Security
#       Repelling the wily hacker
#       William R. Cheswick, Steven M. Bellowin
#
#       Addison-Wesley
#       ISBN 0-201-6337-4
#       http://www.awl.com/
#

if [ -n "${1}" ]; then
        firewall_type="${1}"
fi

############
# Set quiet mode if requested
#
case ${firewall_quiet} in
[Yy][Ee][Ss])
        fwcmd="/sbin/ipfw -q"
        ;;
*)
        fwcmd="/sbin/ipfw"
        ;;
esac

############
# Flush out the list before we begin.
#
${fwcmd} -f flush

############
# These rules are required for using natd.  All packets are passed to
# natd before they encounter your remaining rules.  The firewall rules
# will then be run again on each packet after translation by natd,
# minus any divert rules (see natd(8)).
#
case ${natd_enable} in
[Yy][Ee][Ss])
        if [ -n "${natd_interface}" ]; then
              ${fwcmd} add 50 divert natd all from any to any via ${natd_interface}
        fi
        ;;
esac

############
# If you just configured ipfw in the kernel as a tool to solve network
# problems or you just want to disallow some particular kinds of traffic
# then you will want to change the default policy to open.  You can also
# do this as your only action by setting the firewall_type to ``open''.
#
# ${fwcmd} add 65000 pass all from any to any

############
# Only in rare cases do you want to change these rules
#
${fwcmd} add 100 pass all from any to any via lo0
${fwcmd} add 200 deny all from any to 127.0.0.0/8
# If you're using 'options BRIDGE', uncomment the following line to pass ARP
#${fwcmd} add 300 pass udp from 0.0.0.0 2054 to 0.0.0.0


# Prototype setups.
#
case ${firewall_type} in
[Oo][Pp][Ee][Nn])
        ${fwcmd} add 65000 pass all from any to any
        ;;

[Cc][Ll][Ii][Ee][Nn][Tt])
        ############
        # 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="192.0.2.0"
        mask="255.255.255.0"
        ip="192.0.2.1"

        # 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 IP fragments to pass through
        ${fwcmd} add pass all from any to any frag

        # 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 by default, unless the
        # IPFIREWALL_DEFAULT_TO_ACCEPT option is set in your kernel
        # config file.
        ;;

[Ss][Ii][Mm][Pp][Ll][Ee])
        ############
        # 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
        iif="ed0"
        inet="192.168.1.0"
        imask="255.255.255.0"
        iip="192.168.1.100"

        # set these to your inside interface network and netmask and ip
        oif="ed1"
        onet="*.*.*.*"
        omask="255.255.255.*"
        oip="*.*.*.*"

        # our rules must rule
        ${fwcmd} add divert natd ip from 192.168.1.0 to any out via ed1
        ${fwcmd} add divert natd ip from any to 212.42.60.107 in via ed1
        ${fwcmd} add divert all from any to any via ed1

        # 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 10.0.0.0/8 to any via ${oif}
        ${fwcmd} add deny all from any to 10.0.0.0/8 via ${oif}
        ${fwcmd} add deny all from 172.16.0.0/12 to any via ${oif}
        ${fwcmd} add deny all from any to 172.16.0.0/12 via ${oif}
        ${fwcmd} add deny all from 192.168.0.0/16 to any via ${oif}
        ${fwcmd} add deny all from any to 192.168.0.0/16 via ${oif}

        # Stop draft-manning-dsua-01.txt nets on the outside interface
        ${fwcmd} add deny all from 0.0.0.0/8 to any via ${oif}
        ${fwcmd} add deny all from any to 0.0.0.0/8 via ${oif}
        ${fwcmd} add deny all from 169.254.0.0/16 to any via ${oif}
        ${fwcmd} add deny all from any to 169.254.0.0/16 via ${oif}
        ${fwcmd} add deny all from 192.0.2.0/24 to any via ${oif}
        ${fwcmd} add deny all from any to 192.0.2.0/24 via ${oif}
        ${fwcmd} add deny all from 224.0.0.0/4 to any via ${oif}
        ${fwcmd} add deny all from any to 224.0.0.0/4 via ${oif}
        ${fwcmd} add deny all from 240.0.0.0/4 to any via ${oif}
        ${fwcmd} add deny all from any to 240.0.0.0/4 via ${oif}

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

        # Allow IP fragments to pass through
        ${fwcmd} add pass all from any to any frag

        # 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
        ${fwcmd} add pass udp from any to ${oip} 53
        ${fwcmd} add pass udp from ${oip} 53 to any

        # 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 by default, unless the
        # IPFIREWALL_DEFAULT_TO_ACCEPT option is set in your kernel
        # config file.
        ;;

[Uu][Nn][Kk][Nn][Oo][Ww][Nn])
#       ;;
#*)
        if [ -r "${firewall_type}" ]; then
                ${fwcmd} ${firewall_flags} ${firewall_type}
        fi
        ${fwcmd} add divert natd ip from 192.168.1.0 to any out via ed1
        ${fwcmd} add divert natd ip from any to *.*.*.* in via ed1
        ${fwcmd} add divert all from any to any via ed1

        ${fwcmd} -q add 1 allow tcp from any to *.*.*.* 80 in via ed1
        ${fwcmd} -q add 2 allow tcp from *.*.*.* to *.*.*.* 20,21 in via ed1
        ${fwcmd} -q add 3 allow tcp from *.*.*.* to *.*.*.* 22 in via ed1
        ${fwcmd} -q add 4 allow udp from any to any 53
        ${fwcmd} -q add 5 allow tcp from 192.168.1.0 to any 20,21,22,139 in via ed1
        ${fwcmd} -q add 51 reset tcp from any to *.*.*.* 1-1024 in via ed1
        ${fwcmd} -q add 52 drop udp from any to any 1-1024 in via ed1
        ${fwcmd} -q add 53 unreach port tcp from any to *.*.*.* 1025-65535 in setup
        ;;
esac
=========================================

-- 
Best regards,
Vasily
vasily@maryno.net



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