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  <!--$Id$-->

  <articleinfo>
    <title>About My Network</title>

    <authorgroup>
      <author>
        <firstname>Tom</firstname>

        <surname>Eastep</surname>
      </author>
    </authorgroup>

    <pubdate>2004-07-04</pubdate>

    <copyright>
      <year>2001-2004</year>

      <holder>Thomas M. Eastep</holder>
    </copyright>

    <legalnotice>
      <para>Permission is granted to copy, distribute and/or modify this
      document under the terms of the GNU Free Documentation License, Version
      1.2 or any later version published by the Free Software Foundation; with
      no Invariant Sections, with no Front-Cover, and with no Back-Cover
      Texts. A copy of the license is included in the section entitled
      <quote><ulink url="GnuCopyright.htm">GNU Free Documentation License</ulink></quote>.</para>
    </legalnotice>
  </articleinfo>

  <section>
    <title>My Current Network</title>

    <caution>
      <para>I use a combination of One-to-one NAT and Proxy ARP, neither of
      which are relevant to a simple configuration with a single public IP
      address. If you have just a single public IP address, most of what you
      see here won&#39;t apply to your setup so beware of copying parts of
      this configuration and expecting them to work for you. What you copy may
      or may not work for you.</para>
    </caution>

    <caution>
      <para>The configuration shown here corresponds to Shorewall version
      2.0.3. My configuration uses features not available in earlier Shorewall
      releases.</para>
    </caution>

    <para>I have DSL service and have 5 static IP addresses
    (206.124.146.176-180). My DSL <quote>modem</quote> (Fujitsu Speedport) is
    connected to eth0. I have a local network connected to eth2 (subnet
    192.168.1.0/24) and a DMZ connected to eth1 (206.124.146.176/32). Note
    that I configure the same IP address on both <filename class="devicefile">eth0</filename>
    and <filename class="devicefile">eth1</filename>.</para>

    <para>In this configuration:</para>

    <itemizedlist>
      <listitem>
        <para>I use one-to-one NAT for Ursa (my personal system that
        dual-boots Mandrake 10.0 (Official) and Windows XP) - Internal address
        192.168.1.5 and external address 206.124.146.178.</para>
      </listitem>

      <listitem>
        <para>I use one-to-one NAT for EastepLaptop (My work system -- Windows
        XP SP1). Internal address 192.168.1.7 and external address
        206.124.146.180.</para>
      </listitem>

      <listitem>
        <para>I use SNAT through 206.124.146.179 for&#x00A0; my SuSE 9.0 Linux
        system <quote>Wookie</quote>, my Wife&#39;s Windows XP system
        <quote>Tarry</quote>, and our&#x00A0; dual-booting (Windows
        XP/Mandrake 10.0 Official) laptop <quote>Tipper</quote> which connects
        through the Wireless Access Point (wap) via a Wireless Bridge (wet).<note><para>While
        the distance between the WAP and where I usually use the laptop
        isn&#39;t very far (25 feet or so), using a WAC11 (CardBus wireless
        card) has proved very unsatisfactory (lots of lost connections). By
        replacing the WAC11 with the WET11 wireless bridge, I have virtually
        eliminated these problems (Being an old radio tinkerer (K7JPV), I was
        also able to eliminate the disconnects by hanging a piece of aluminum
        foil on the family room wall. Needless to say, my wife Tarry rejected
        that as a permanent solution :-).</para></note></para>
      </listitem>
    </itemizedlist>

    <itemizedlist>
      <listitem>
        <para>I have Wookie (193.168.1.3) configured as a 3-port bridge. Squid
        runs on this system and is configured as a transparent proxy.</para>
      </listitem>
    </itemizedlist>

    <para>The firewall runs on a 256MB PII/233 with Debian Sarge (Testing).</para>

    <para>Wookie and Ursa run Samba and Wookie acts as a WINS server.</para>

    <para>The wireless network connects to Wookie&#39;s eth2 via a LinkSys
    WAP11.&#x00A0; In additional to using the rather weak WEP 40-bit
    encryption (64-bit with the 24-bit preamble), I use <ulink
    url="MAC_Validation.html">MAC verification</ulink>. This is still a weak
    combination and if I lived near a wireless <quote>hot spot</quote>, I
    would probably add IPSEC or something similar to my WiFi-&#62;local
    connections.</para>

    <para>The single system in the DMZ (address 206.124.146.177) runs postfix,
    Courier IMAP (imaps and pop3), DNS, a Web server (Apache) and an FTP
    server (Pure-ftpd) under Fedora Core 2. The system also runs fetchmail to
    fetch our email from our old and current ISPs. That server is managed
    through Proxy ARP.</para>

    <para>The firewall system itself runs a DHCP server that serves the local
    network.</para>

    <para>All administration and publishing is done using ssh/scp. I have a
    desktop environment installed on the firewall but I am not usually logged
    in to it. X applications tunnel through SSH to Ursa. The server also has a
    desktop environment installed and that desktop environment is available
    via XDMCP from the local zone. For the most part though, X tunneled
    through SSH is used for server administration and the server runs at run
    level 3 (multi-user console mode on Fedora).</para>

    <para>I run an SNMP server on my firewall to serve <ulink
    url="http://www.ee.ethz.ch/~oetiker/webtools/mrtg/">MRTG</ulink> running
    in the DMZ.</para>

    <para>The ethernet interface in the Server is configured with IP address
    206.124.146.177, netmask 255.255.255.0. The server&#39;s default gateway
    is 206.124.146.254 (Router at my ISP. This is the same default gateway
    used by the firewall itself). On the firewall, an entry in my
    /etc/network/interfaces file (see below) adds a host route to
    206.124.146.177 through eth1 when that interface is brought up.</para>

    <para>Tarry (192.168.1.4) runs a PPTP server for Road Warrior access.</para>

    <para><graphic align="center" fileref="images/network.png" /></para>
  </section>

  <section>
    <title>Firewall Configuration</title>

    <section>
      <title>Shorewall.conf</title>

      <blockquote>
        <programlisting>LOGFILE=/var/log/messages
LOGRATE=
LOGBURST=
LOGUNCLEAN=$LOG
BLACKLIST_LOGLEVEL=
LOGNEWNOTSYN=$LOG
MACLIST_LOG_LEVEL=$LOG
TCP_FLAGS_LOG_LEVEL=$LOG
RFC1918_LOG_LEVEL=$LOG
SMURF_LOG_LEVEL=
PATH=/sbin:/bin:/usr/sbin:/usr/bin:/usr/local/bin:/usr/local/sbin
SHOREWALL_SHELL=/bin/ash
SUBSYSLOCK=               #I run Debian which doesn&#39;t use service locks
STATEDIR=/var/state/shorewall
MODULESDIR=
FW=fw
IP_FORWARDING=On
ADD_IP_ALIASES=Yes
ADD_SNAT_ALIASES=Yes
TC_ENABLED=Yes
CLEAR_TC=No
MARK_IN_FORWARD_CHAIN=No
CLAMPMSS=Yes
ROUTE_FILTER=No
DETECT_DNAT_IPADDRS=Yes
MUTEX_TIMEOUT=60
NEWNOTSYN=Yes
BLACKLISTNEWONLY=Yes
BLACKLIST_DISPOSITION=DROP
MACLIST_DISPOSITION=REJECT
TCP_FLAGS_DISPOSITION=DROP
</programlisting>
      </blockquote>
    </section>

    <section>
      <title>Params File (Edited)</title>

      <blockquote>
        <para><programlisting>MIRRORS=&#60;list of shorewall mirror ip addresses&#62;
NTPSERVERS=&#60;list of the NTP servers I sync with&#62;
TEXAS=&#60;ip address of gateway in Plano&#62;
LOG=info</programlisting></para>
      </blockquote>
    </section>

    <section>
      <title>Zones File</title>

      <blockquote>
        <programlisting>#ZONE   DISPLAY         COMMENTS
net     Internet        Internet
dmz     DMZ             Demilitarized zone
loc     Local           Local networks
tx      Texas           Peer Network in Plano
#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS ONE - DO NOT REMOVE</programlisting>
      </blockquote>
    </section>

    <section>
      <title>Interfaces File</title>

      <blockquote>
        <para>This is set up so that I can start the firewall before bringing
        up my Ethernet interfaces.</para>

        <programlisting>#ZONE   INERFACE        BROADCAST       OPTIONS
net     eth0            206.124.146.255 dhcp,norfc1918,routefilter,blacklist,tcpflags,nosmurfs
loc     eth2            192.168.1.255   dhcp,detectnets
dmz     eth1            -
-       texas           192.168.9.255
#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS ONE - DO NOT REMOVE</programlisting>
      </blockquote>
    </section>

    <section>
      <title>Hosts File</title>

      <blockquote>
        <programlisting>#ZONE           HOST(S)                 OPTIONS
tx&#x00A0;&#x00A0;&#x00A0;&#x00A0;&#x00A0;&#x00A0;&#x00A0;&#x00A0;&#x00A0;&#x00A0;&#x00A0;&#x00A0;&#x00A0; texas:192.168.8.0/22
#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS ONE - DO NOT REMOVE</programlisting>
      </blockquote>
    </section>

    <section>
      <title>Routestopped File</title>

      <blockquote>
        <programlisting>#INTERFACE      HOST(S)
eth1            206.124.146.177
eth2            -
#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS ONE - DO NOT REMOVE</programlisting>
      </blockquote>
    </section>

    <section>
      <title>Blacklist File (Partial)</title>

      <blockquote>
        <programlisting>#ADDRESS/SUBNET         PROTOCOL        PORT
0.0.0.0/0               udp             1434
0.0.0.0/0               tcp             1433
0.0.0.0/0               tcp             3127
0.0.0.0/0               tcp             8081
0.0.0.0/0               tcp             57
#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS ONE - DO NOT REMOVE</programlisting>
      </blockquote>
    </section>

    <section>
      <title>Policy File</title>

      <blockquote>
        <programlisting>#SOURCE         DESTINATION     POLICY          LOG LEVEL       BURST:LIMIT
fw              fw              ACCEPT                                    # For testing fw-&#62;fw rules
loc             net             ACCEPT                                    # Allow all net traffic from local net
$FW             loc             ACCEPT                                    # Allow local access from the firewall
$FW             tx              ACCEPT                                    # Allow firewall access to texas
loc             tx              ACCEPT                                    # Allow local net access to texas
loc             fw              REJECT          $LOG                      # Reject loc-&#62;fw and log
net             all             DROP            $LOG            10/sec:40 # Rate limit and
                                                                          # DROP net-&#62;all
all             all             REJECT          $LOG                      # Reject and log the rest
#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS ONE - DO NOT REMOVE</programlisting>
      </blockquote>
    </section>

    <section>
      <title>Masq File</title>

      <blockquote>
        <para>Although most of our internal systems use one-to-one NAT, my
        wife&#39;s system (192.168.1.4) uses IP Masquerading (actually SNAT)
        as do my SuSE system (192.168.1.3), our laptop (192.168.3.8) and
        visitors with laptops.</para>

        <programlisting>#INTERFACE              SUBNET          ADDRESS
eth0:2                  eth2            206.124.146.179
#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS LINE -- DO NOT REMOVE
</programlisting>
      </blockquote>
    </section>

    <section>
      <title>NAT File</title>

      <blockquote>
        <programlisting>#EXTERNAL       INTERFACE       INTERNAL        ALL INTERFACES          LOCAL
206.124.146.178 eth0:0          192.168.1.5     No                      No
206.124.146.180 eth0:1          192.168.1.7     No                      No
#
# The following entry allows the server to be accessed through an address in
# the local network. This is convenient when I&#39;m on the road and connected
# to the PPTP server. By doing this, I don&#39;t need to set my client&#39;s default
# gateway to route through the tunnel.
#
192.168.1.193   eth2:0          206.124.146.177 No                      No
#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS LINE -- DO NOT REMOVE</programlisting>
      </blockquote>
    </section>

    <section id="ProxyARP">
      <title>Proxy ARP File</title>

      <blockquote>
        <programlisting>#ADDRESS                INTERFACE       EXTERNAL        HAVEROUTE          PERSISTENT
206.124.146.177         eth1            eth0            Yes
#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE</programlisting>
      </blockquote>
    </section>

    <section>
      <title>Tunnels File (Shell variable TEXAS set in /etc/shorewall/params)</title>

      <blockquote>
        <programlisting>#TYPE                   ZONE    GATEWAY         GATEWAY ZONE    PORT
gre                     net     $TEXAS
#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE</programlisting>
      </blockquote>
    </section>

    <section id="Actions">
      <title>Actions File</title>

      <blockquote>
        <programlisting>#ACTION
Mirrors             #Accept traffic from the Shorewall Mirror sites
#LAST LINE - ADD YOUR ENTRIES ABOVE THIS ONE - DO NOT REMOVE</programlisting>
      </blockquote>
    </section>

    <section>
      <title>action.Mirrors File</title>

      <blockquote>
        <para>The $MIRRORS variable expands to a list of approximately 10 IP
        addresses. So moving these checks into a separate chain reduces the
        number of rules that most net-&#62;dmz traffic needs to traverse.</para>

        <programlisting>#TARGET  SOURCE         DEST            PROTO   DEST    SOURCE     ORIGINAL     RATE
#                                               PORT    PORT(S)    DEST         LIMIT
ACCEPT   $MIRRORS                      
#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE</programlisting>
      </blockquote>
    </section>

    <section>
      <title>/etc/shorewall/action.Drop</title>

      <blockquote>
        <para>This is my common action for the DROP policy. It is like the
        standard <emphasis role="bold">Drop</emphasis> action except that it
        allows <quote>Ping</quote>.</para>

        <programlisting>#TARGET  SOURCE     DEST          PROTO   DEST      SOURCE      RATE         USER/
#                                         PORT(S)   PORT(S)     LIMIT        GROUP
RejectAuth
AllowPing
dropBcast
DropSMB
DropUPnP
dropNonSyn
DropDNSrep</programlisting>
      </blockquote>
    </section>

    <section>
      <title>/etc/shorewall/action.Reject</title>

      <blockquote>
        <para>This is my common action for the REJECT policy. It is like the
        standard <emphasis role="bold">Reject</emphasis> action except that it
        allows <quote>Ping</quote> and contains one rule that guards against
        log flooding by broken software running in my local zone.</para>

        <programlisting>#TARGET  SOURCE     DEST          PROTO   DEST      SOURCE      RATE         USER/
#                                         PORT(S)   PORT(S)     LIMIT        GROUP
RejectAuth
AllowPing
dropBcast
RejectSMB
DropUPnP
dropNonSyn
DropDNSrep
DROP      loc:eth2:!192.168.1.0/24       #So that my braindead Windows[tm] XP system doesn&#39;t flood my log
                                         #with NTP requests with a source address in 16.0.0.0/8 (address of
                                         #its PPTP tunnel to HP).</programlisting>
      </blockquote>
    </section>

    <section>
      <title>Rules File (The shell variables are set in /etc/shorewall/params)</title>

      <blockquote>
        <programlisting>###############################################################################################################################################################################
#RESULT         CLIENT(S)                       SERVER(S)               PROTO   PORT(S)                                 CLIENT          ORIGINAL        RATE    USER
#                                                                                                                       PORT(S)         DEST:SNAT               SET
###############################################################################################################################################################################
# Local Network to Internet - Reject attempts by Trojans to call home
#
REJECT:$LOG     loc                             net                     tcp     6667
#
# Stop NETBIOS crap since our policy is ACCEPT
#
REJECT          loc                             net                     tcp     137,445
REJECT          loc                             net                     udp     137:139
#
QUEUE           loc                             net                     udp
QUEUE           loc                             fw                      udp
QUEUE           loc                             net                     tcp
###############################################################################################################################################################################
# Local Network to Firewall
#
ACCEPT          loc                             fw                      tcp     ssh,time
ACCEPT          loc                             fw                      udp     snmp,ntp
###############################################################################################################################################################################
# Local Network to DMZ
#
REJECT          loc                             dmz                     tcp     465
ACCEPT          loc                             dmz                     udp     domain,xdmcp
ACCEPT          loc                             dmz                     tcp     www,smtp,domain,ssh,imap,https,imaps,cvspserver,ftp,10000,8080,10027,pop3       -
###############################################################################################################################################################################
# Internet to DMZ
#
DNAT-           net                             dmz:206.124.146.177     tcp     smtp                                    -               206.124.146.179,206.124.146.178
ACCEPT          net                             dmz                     tcp     smtp,www,ftp,imaps,domain,cvspserver,https      -
ACCEPT          net                             dmz                     udp     domain
ACCEPT          net                             dmz                     udp     33434:33436
Mirrors         net                             dmz                     tcp     rsync
#ACCEPT:$LOG    net                             dmz                     tcp     32768:61000                             20
###############################################################################################################################################################################
#
# Net to Local
#
# When I&#39;m &#34;on the road&#34;, the following two rules allow me VPN access back home.
#
DNAT            net                             loc:192.168.1.4         tcp     1723
DNAT            net                             loc:192.168.1.4         gre
#
# ICQ
#
ACCEPT          net                             loc:192.168.1.5         tcp     4000:4100
#
# Real Audio
#
ACCEPT          net                             loc:192.168.1.5         udp     6970:7170
#
# Overnet
#
#ACCEPT         net                             loc:192.168.1.5         tcp     4662
#ACCEPT         net                             loc:192.168.1.5         udp     12112
###############################################################################################################################################################################
# DMZ to Internet
#
ACCEPT          dmz                             net                     tcp     smtp,domain,www,https,whois,echo,2702,21,2703,ssh,8080
ACCEPT          dmz                             net                     udp     domain
ACCEPT          dmz                             net:$POPSERVERS         tcp     pop3
#ACCEPT         dmz                             net:206.191.151.2       tcp     pop3
#ACCEPT         dmz                             net:66.216.26.115       tcp     pop3
#
# Something is wrong with the FTP connection tracking code or there is some client out there
# that is sending a PORT command which that code doesn&#39;t understand. Either way,
# the following works around the problem.
#
ACCEPT:$LOG     dmz                             net                     tcp     1024:                                   20
###############################################################################################################################################################################
# DMZ to Firewall -- ntp &#38; snmp, Silently reject Auth
#
ACCEPT          dmz                             fw                      udp     ntp                                     ntp
ACCEPT          dmz                             fw                      tcp     snmp,ssh
ACCEPT          dmz                             fw                      udp     snmp
REJECT          dmz                             fw                      tcp     auth
###############################################################################################################################################################################
# DMZ to Local Network
#
ACCEPT          dmz                             loc                     tcp     smtp,6001:6010
ACCEPT          dmz:206.124.146.177             loc:192.168.1.3         tcp     111
ACCEPT          dmz:206.124.146.177             loc:192.168.1.3         udp
###############################################################################################################################################################################
# Internet to Firewall
#
REJECT          net                             fw                      tcp     www
ACCEPT          net                             dmz                     udp     33434:33435

###############################################################################################################################################################################
# Firewall to Internet
#
ACCEPT          fw                              net:$NTPSERVERS         udp     ntp                                     ntp
#ACCEPT         fw                              net:$POPSERVERS         tcp     pop3
ACCEPT          fw                              net                     udp     domain
ACCEPT          fw                              net                     tcp     domain,www,https,ssh,1723,whois,1863,ftp,2702,2703,7
ACCEPT          fw                              net                     udp     33435:33535
ACCEPT          fw                              net                     icmp
###############################################################################################################################################################################
# Firewall to DMZ
#
ACCEPT          fw                              dmz                     tcp     www,ftp,ssh,smtp
ACCEPT          fw                              dmz                     udp     domain
REJECT          fw                              dmz                     udp     137:139
###############################################################################################################################################################################
# Ping
#
ACCEPT          all                             all                     icmp    8
#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE</programlisting>
      </blockquote>
    </section>

    <section id="Interfaces">
      <title>/etc/network/interfaces</title>

      <blockquote>
        <para>This file is Debian specific. My additional entry (which is
        displayed in <emphasis role="bold">bold type</emphasis>) adds a route
        to my DMZ server when eth1 is brought up. It allows me to enter
        <quote>Yes</quote> in the HAVEROUTE column of <link linkend="ProxyARP">my
        Proxy ARP file</link>.</para>

        <programlisting>...
auto eth1
iface eth1 inet static
        address 206.124.146.176
        netmask 255.255.255.255
        broadcast 0.0.0.0
        <emphasis role="bold">up ip route add 206.124.146.177 dev eth1
</emphasis>...</programlisting>
      </blockquote>
    </section>
  </section>

  <section>
    <title>Bridge (Wookie) Configuration</title>

    <para>As mentioned above, Wookie acts as a bridge. It&#39;s view of the
    network is diagrammed in the following figure.</para>

    <graphic fileref="images/network1.png" />

    <para>I&#39;ve included the files that I used to configure that system --
    some of them are SuSE-specific.</para>

    <para>The configuration on Wookie can be modified to test various bridging
    features -- otherwise, it serves to isolate the Wireless network from the
    rest of our systems.</para>

    <section>
      <title>shorewall.conf</title>

      <blockquote>
        <para>Only the changes from the defaults are shown.</para>

        <programlisting>BRIDGING=Yes</programlisting>
      </blockquote>
    </section>

    <section>
      <title>zones</title>

      <blockquote>
        <programlisting>#ZONE   DISPLAY         COMMENTS
net     Net             Internet
loc     Local           Local networks
WiFi    WireLess        Wireless Network
#LAST LINE - ADD YOUR ENTRIES ABOVE THIS ONE - DO NOT REMOVE
</programlisting>
      </blockquote>
    </section>

    <section>
      <title>policy</title>

      <blockquote>
        <programlisting>#SOURCE         DEST            POLICY          LOG             LIMIT:BURST
fw              fw              ACCEPT
loc             net             ACCEPT
net             loc             ACCEPT
net             fw              ACCEPT
loc             fw              ACCEPT
loc             WiFi            ACCEPT
fw              WiFi            ACCEPT
fw              net             ACCEPT
fw              loc             ACCEPT
#
# THE FOLLOWING POLICY MUST BE LAST
#
all             all             REJECT          info
#LAST LINE -- DO NOT REMOVE</programlisting>
      </blockquote>
    </section>

    <section>
      <title>interfaces</title>

      <blockquote>
        <programlisting>#ZONE    INTERFACE      BROADCAST       OPTIONS
-       br0             192.168.1.255
#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE</programlisting>
      </blockquote>
    </section>

    <section>
      <title>hosts</title>

      <blockquote>
        <programlisting>#ZONE           HOST(S)                         OPTIONS
net             br0:eth1
loc             br0:eth0
WiFi            br0:eth2                        maclist
#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS LINE -- DO NOT REMOVE</programlisting>
      </blockquote>
    </section>

    <section>
      <title>rules</title>

      <blockquote>
        <para>The first rule allows a transparent WWW proxy (Squid) to run on
        my bridge/firewall. Squid listens on port 3128.</para>

        <para>The remaining rules protect the local systems and bridge from
        the WiFi network. Note that we don&#39;t restrict WiFi→net traffic
        since the only directly-accessible system in the net zone is the
        firewall (Wookie and the Firewall are connected by a cross-over
        cable).</para>

        <programlisting>#ACTION    SOURCE          DEST            PROTO   DEST    SOURCE  ORIGINAL
#                                          PORT            PORT(S) DEST
REDIRECT   loc             3128            tcp     www     -       !192.168.1.0/24

ACCEPT     WiFi            loc             udp     137:139
ACCEPT     WiFi            loc             tcp     22,80,137,139,445,901,3389
ACCEPT     WiFi            loc             udp     1024:                                   137
ACCEPT     WiFi            loc             udp     177

ACCEPT     loc             WiFi            udp     137:139
ACCEPT     loc             WiFi            tcp     137,139,445
ACCEPT     loc             WiFi            udp     1024:                                   137
ACCEPT     loc             WiFi            tcp     6000:6010

ACCEPT     WiFi            fw              tcp     ssh,137,139,445
ACCEPT     WiFi            fw              udp     137:139,445
ACCEPT     WiFi            fw              udp     1024:                                   137
ACCEPT     WiFi            fw              udp     ntp

#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE</programlisting>
      </blockquote>
    </section>

    <section>
      <title>routestopped</title>

      <blockquote>
        <programlisting>#INTERFACE      HOST(S)         OPTIONS
br0             0.0.0.0/0       routeback
#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE</programlisting>
      </blockquote>
    </section>

    <section>
      <title>maclist</title>

      <blockquote>
        <programlisting>#INTERFACE              MAC                     IP ADDRESSES (Optional)
br0:eth2                00:A0:1C:DB:0C:A0       192.168.1.7     #Work Laptop
br0:eth2                00:04:59:0e:85:b9                       #WAP11
br0:eth2                00:06:D5:45:33:3c                       #WET11
br0:eth2                00:0b:c1:53:cc:97       192.168.1.8     #TIPPER
#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS LINE -- DO NOT REMOVE</programlisting>
      </blockquote>
    </section>

    <section>
      <title>/etc/init.d/bridge</title>

      <blockquote>
        <para>This file is SuSE-specific and creates the bridge device
        <filename class="devicefile">br0</filename>. A script for other
        disbributions would be similar.</para>

        <programlisting>#!/bin/sh
################################################################################
#   Script to create a bridge between eth0, eth1 and eth2
#
#     This program is under GPL [http://www.gnu.org/copyleft/gpl.htm]
#
#     (c) 2004 - Tom Eastep (teastep@shorewall.net)
#
#   Modify the following variables to match your configuration
#
# chkconfig: 2345 05 89
# description: Layer 2 Bridge
#
################################################################################

PATH=$PATH:/sbin:/usr/sbin:/usr/local/sbin

do_stop() {
    echo &#34;Stopping Bridge&#34;
    brctl delbr br0
    ip link set eth0 down
    ip link set eth1 down
    ip link set eth2 down
}

do_start() {

      echo &#34;Starting Bridge&#34;
      ip link set eth0 up
      ip link set eth1 up
      ip link set eth2 up
      brctl addbr br0
      brctl addif br0 eth0
      brctl addif br0 eth1
      brctl addif br0 eth2
}

case &#34;$1&#34; in
  start)
      do_start
    ;;
  stop)
      do_stop
    ;;
  restart)
      do_stop
      sleep 1
      do_start
    ;;
  *)
    echo &#34;Usage: $0 {start|stop|restart}&#34;
    exit 1
esac
exit 0</programlisting>
      </blockquote>
    </section>

    <section>
      <title>/etc/sysconfig/network/ifcfg-br0</title>

      <blockquote>
        <para>This file is SuSE-specific</para>

        <programlisting>BOOTPROTO=&#39;static&#39;
BROADCAST=&#39;192.168.1.255&#39;
IPADDR=&#39;192.168.1.3&#39;
NETWORK=&#39;192.168.1.0&#39;
NETMASK=&#39;255.255.255.0&#39;
REMOTE_IPADDR=&#39;&#39;
STARTMODE=&#39;onboot&#39;
UNIQUE=&#39;3hqH.MjuOqWfSZ+C&#39;
WIRELESS=&#39;no&#39;
MTU=&#39;&#39;</programlisting>
      </blockquote>
    </section>

    <section>
      <title>/etc/sysconfig/network/routes</title>

      <blockquote>
        <para>This file is SuSE-specific</para>

        <programlisting>192.168.1.0 - 255.255.255.0 br0
default 192.168.1.254 - -</programlisting>
      </blockquote>
    </section>
  </section>
</article>