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830 lines
31 KiB
XML
830 lines
31 KiB
XML
<?xml version="1.0" encoding="UTF-8"?>
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<!DOCTYPE article PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
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"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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<article>
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<!--$Id$-->
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<articleinfo>
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<title>About My Network</title>
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<authorgroup>
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<author>
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<firstname>Tom</firstname>
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<surname>Eastep</surname>
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</author>
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</authorgroup>
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<pubdate>2004-07-13</pubdate>
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<copyright>
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<year>2001-2004</year>
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<holder>Thomas M. Eastep</holder>
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</copyright>
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<legalnotice>
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<para>Permission is granted to copy, distribute and/or modify this
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document under the terms of the GNU Free Documentation License, Version
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1.2 or any later version published by the Free Software Foundation; with
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no Invariant Sections, with no Front-Cover, and with no Back-Cover
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Texts. A copy of the license is included in the section entitled
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<quote><ulink url="GnuCopyright.htm">GNU Free Documentation License</ulink></quote>.</para>
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</legalnotice>
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</articleinfo>
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<section>
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<title>My Current Network</title>
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<caution>
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<para>I use a combination of One-to-one NAT and Proxy ARP, neither of
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which are relevant to a simple configuration with a single public IP
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address. If you have just a single public IP address, most of what you
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see here won't apply to your setup so beware of copying parts of
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this configuration and expecting them to work for you. What you copy may
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or may not work for you.</para>
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</caution>
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<caution>
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<para>The configuration shown here corresponds to Shorewall version
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2.1.1. My configuration uses features not available in earlier Shorewall
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releases.</para>
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</caution>
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<para>I have DSL service and have 5 static IP addresses
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(206.124.146.176-180). My DSL <quote>modem</quote> (Westell 2200) is
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connected to eth0 and has IP address 192.168.1.1 (factory default). I have
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a local network connected to eth2 (subnet 192.168.1.0/24) and a DMZ
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connected to eth1 (206.124.146.176/32). Note that I configure the same IP
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address on both <filename class="devicefile">eth0</filename> and <filename
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class="devicefile">eth1</filename>.</para>
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<para>In this configuration:</para>
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<itemizedlist>
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<listitem>
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<para>I use one-to-one NAT for Ursa (my personal system that
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dual-boots Mandrake 10.0 (Official) and Windows XP) - Internal address
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192.168.1.5 and external address 206.124.146.178.</para>
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</listitem>
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<listitem>
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<para>I use one-to-one NAT for EastepLaptop (My work system -- Windows
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XP SP1). Internal address 192.168.1.7 and external address
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206.124.146.180.</para>
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</listitem>
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<listitem>
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<para>I use SNAT through 206.124.146.179 for  my SuSE 9.0 Linux
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system <quote>Wookie</quote>, my Wife's Windows XP system
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<quote>Tarry</quote>, and our  dual-booting (Windows
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XP/Mandrake 10.0 Official) laptop <quote>Tipper</quote> which connects
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through the Wireless Access Point (wap) via a Wireless Bridge (wet).<note><para>While
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the distance between the WAP and where I usually use the laptop
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isn't very far (25 feet or so), using a WAC11 (CardBus wireless
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card) has proved very unsatisfactory (lots of lost connections). By
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replacing the WAC11 with the WET11 wireless bridge, I have virtually
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eliminated these problems (Being an old radio tinkerer (K7JPV), I was
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also able to eliminate the disconnects by hanging a piece of aluminum
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foil on the family room wall. Needless to say, my wife Tarry rejected
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that as a permanent solution :-).</para></note></para>
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</listitem>
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</itemizedlist>
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<itemizedlist>
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<listitem>
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<para>I have Wookie (193.168.1.3) configured as a 3-port bridge. Squid
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runs on this system and is configured as a transparent proxy.</para>
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</listitem>
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</itemizedlist>
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<para>The firewall runs on a 256MB PII/233 with Debian Sarge (Testing).</para>
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<para>Wookie and Ursa run Samba and Wookie acts as a WINS server.</para>
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<para>The wireless network connects to Wookie's eth2 via a LinkSys
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WAP11.  In additional to using the rather weak WEP 40-bit
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encryption (64-bit with the 24-bit preamble), I use <ulink
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url="MAC_Validation.html">MAC verification</ulink>. This is still a weak
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combination and if I lived near a wireless <quote>hot spot</quote>, I
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would probably add IPSEC or something similar to my WiFi->local
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connections.</para>
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<para>The single system in the DMZ (address 206.124.146.177) runs postfix,
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Courier IMAP (imaps and pop3), DNS, a Web server (Apache) and an FTP
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server (Pure-ftpd) under Fedora Core 2. The system also runs fetchmail to
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fetch our email from our old and current ISPs. That server is managed
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through Proxy ARP.</para>
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<para>The firewall system itself runs a DHCP server that serves the local
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network.</para>
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<para>All administration and publishing is done using ssh/scp. I have a
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desktop environment installed on the firewall but I am not usually logged
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in to it. X applications tunnel through SSH to Ursa. The server also has a
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desktop environment installed and that desktop environment is available
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via XDMCP from the local zone. For the most part though, X tunneled
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through SSH is used for server administration and the server runs at run
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level 3 (multi-user console mode on Fedora).</para>
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<para>I run an SNMP server on my firewall to serve <ulink
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url="http://www.ee.ethz.ch/~oetiker/webtools/mrtg/">MRTG</ulink> running
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in the DMZ.</para>
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<para>The ethernet interface in the Server is configured with IP address
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206.124.146.177, netmask 255.255.255.0. The server's default gateway
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is 206.124.146.254 (Router at my ISP. This is the same default gateway
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used by the firewall itself). On the firewall, an entry in my
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/etc/network/interfaces file (see below) adds a host route to
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206.124.146.177 through eth1 when that interface is brought up.</para>
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<para>Tarry (192.168.1.4) runs a PPTP server for Road Warrior access.</para>
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<para><graphic align="center" fileref="images/network.png" /></para>
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</section>
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<section>
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<title>Firewall Configuration</title>
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<section>
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<title>Shorewall.conf</title>
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<blockquote>
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<programlisting>LOGFILE=/var/log/messages
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LOGRATE=
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LOGBURST=
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LOGUNCLEAN=$LOG
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BLACKLIST_LOGLEVEL=
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LOGNEWNOTSYN=$LOG
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MACLIST_LOG_LEVEL=$LOG
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TCP_FLAGS_LOG_LEVEL=$LOG
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RFC1918_LOG_LEVEL=$LOG
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SMURF_LOG_LEVEL=
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PATH=/sbin:/bin:/usr/sbin:/usr/bin:/usr/local/bin:/usr/local/sbin
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SHOREWALL_SHELL=/bin/ash
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SUBSYSLOCK= #I run Debian which doesn't use service locks
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STATEDIR=/var/state/shorewall
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MODULESDIR=
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FW=fw
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IP_FORWARDING=On
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ADD_IP_ALIASES=Yes
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ADD_SNAT_ALIASES=Yes
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TC_ENABLED=Yes
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CLEAR_TC=No
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MARK_IN_FORWARD_CHAIN=No
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CLAMPMSS=Yes
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ROUTE_FILTER=No
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DETECT_DNAT_IPADDRS=Yes
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MUTEX_TIMEOUT=60
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NEWNOTSYN=Yes
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BLACKLISTNEWONLY=Yes
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BLACKLIST_DISPOSITION=DROP
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MACLIST_DISPOSITION=REJECT
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TCP_FLAGS_DISPOSITION=DROP
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</programlisting>
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</blockquote>
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</section>
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<section>
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<title>Params File (Edited)</title>
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<blockquote>
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<para><programlisting>MIRRORS=<list of shorewall mirror ip addresses>
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NTPSERVERS=<list of the NTP servers I sync with>
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TEXAS=<ip address of gateway in Plano>
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LOG=info</programlisting></para>
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</blockquote>
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</section>
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<section>
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<title>Zones File</title>
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<blockquote>
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<programlisting>#ZONE DISPLAY COMMENTS
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net Internet Internet
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dmz DMZ Demilitarized zone
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loc Local Local networks
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tx Texas Peer Network in Plano
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#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS ONE - DO NOT REMOVE</programlisting>
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</blockquote>
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</section>
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<section>
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<title>Interfaces File</title>
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<blockquote>
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<para>This is set up so that I can start the firewall before bringing
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up my Ethernet interfaces.</para>
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<programlisting>#ZONE INERFACE BROADCAST OPTIONS
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net eth0 206.124.146.255 dhcp,norfc1918,routefilter,blacklist,tcpflags,nosmurfs
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loc eth2 192.168.1.255 dhcp
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dmz eth1 -
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- texas 192.168.9.255
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#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS ONE - DO NOT REMOVE</programlisting>
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</blockquote>
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</section>
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<section>
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<title>Hosts File</title>
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<blockquote>
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<programlisting>#ZONE HOST(S) OPTIONS
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tx              texas:192.168.8.0/22
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#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS ONE - DO NOT REMOVE</programlisting>
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</blockquote>
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</section>
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<section>
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<title>Routestopped File</title>
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<blockquote>
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<programlisting>#INTERFACE HOST(S)
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eth1 206.124.146.177
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eth2 -
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#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS ONE - DO NOT REMOVE</programlisting>
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</blockquote>
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</section>
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<section>
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<title>Blacklist File (Partial)</title>
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<blockquote>
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<programlisting>#ADDRESS/SUBNET PROTOCOL PORT
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0.0.0.0/0 udp 1434
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0.0.0.0/0 tcp 1433
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0.0.0.0/0 tcp 3127
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0.0.0.0/0 tcp 8081
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0.0.0.0/0 tcp 57
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#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS ONE - DO NOT REMOVE</programlisting>
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</blockquote>
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</section>
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<section>
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<title>RFC1918 File</title>
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<blockquote>
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<para>Because my DSL modem has an RFC 1918 address (192.168.1.1) and
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is connected to eth0, I need to make an exception for that address in
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my rfc1918 file. I copied /usr/share/shorewall/rfc1918 to
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/etc/shorewall/rfc1918 and changed it as follows:</para>
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<programlisting>#SUBNET TARGET
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<emphasis role="bold">192.168.1.1 RETURN</emphasis>
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172.16.0.0/12 logdrop # RFC 1918
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192.168.0.0/16 logdrop # RFC 1918
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10.0.0.0/8 logdrop # RFC 1918
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#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE
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</programlisting>
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</blockquote>
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</section>
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<section>
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<title>Policy File</title>
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<blockquote>
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<programlisting>#SOURCE DESTINATION POLICY LOG LEVEL BURST:LIMIT
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fw fw ACCEPT # For testing fw->fw rules
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loc net ACCEPT # Allow all net traffic from local net
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$FW loc ACCEPT # Allow local access from the firewall
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$FW tx ACCEPT # Allow firewall access to texas
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loc tx ACCEPT # Allow local net access to texas
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loc fw REJECT $LOG # Reject loc->fw and log
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net all DROP $LOG 10/sec:40 # Rate limit and
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# DROP net->all
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all all REJECT $LOG # Reject and log the rest
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#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS ONE - DO NOT REMOVE</programlisting>
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</blockquote>
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</section>
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<section>
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<title>Masq File</title>
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<blockquote>
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<para>Although most of our internal systems use one-to-one NAT, my
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wife's system (192.168.1.4) uses IP Masquerading (actually SNAT)
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as do my SuSE system (192.168.1.3), our laptop (192.168.3.8) and
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visitors with laptops.</para>
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<para>The first entry allows access to the DSL modem and uses features
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introduced in Shorewall 2.1.1. The leading plus sign ("+_")
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causes the rule to be placed before rules generated by the
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/etc/shorewall/nat file below. The double colons ("::") causes
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the entry to be exempt from ADD_SNAT_ALIASES=Yes in my shorewall.conf
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file above.</para>
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<programlisting>#INTERFACE SUBNET ADDRESS
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+eth0::192.168.1.1 0.0.0.0/0 192.168.1.254
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eth0:2 eth2 206.124.146.179
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#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS LINE -- DO NOT REMOVE
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</programlisting>
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</blockquote>
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</section>
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<section>
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<title>NAT File</title>
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<blockquote>
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<programlisting>#EXTERNAL INTERFACE INTERNAL ALL INTERFACES LOCAL
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206.124.146.178 eth0:0 192.168.1.5 No No
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206.124.146.180 eth0:1 192.168.1.7 No No
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#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS LINE -- DO NOT REMOVE</programlisting>
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</blockquote>
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</section>
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<section id="ProxyARP">
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<title>Proxy ARP File</title>
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<blockquote>
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<programlisting>#ADDRESS INTERFACE EXTERNAL HAVEROUTE PERSISTENT
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206.124.146.177 eth1 eth0 Yes
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192.168.1.1 eth0 eth2 yes # Allow access to DSL modem from the local zone
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#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE</programlisting>
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</blockquote>
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</section>
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<section>
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<title>Tunnels File (Shell variable TEXAS set in /etc/shorewall/params)</title>
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<blockquote>
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<programlisting>#TYPE ZONE GATEWAY GATEWAY ZONE PORT
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gre net $TEXAS
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#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE</programlisting>
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</blockquote>
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</section>
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<section id="Actions">
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<title>Actions File</title>
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<blockquote>
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<programlisting>#ACTION
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Mirrors #Accept traffic from the Shorewall Mirror sites
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#LAST LINE - ADD YOUR ENTRIES ABOVE THIS ONE - DO NOT REMOVE</programlisting>
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</blockquote>
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</section>
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<section>
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<title>action.Mirrors File</title>
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<blockquote>
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<para>The $MIRRORS variable expands to a list of approximately 10 IP
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addresses. So moving these checks into a separate chain reduces the
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number of rules that most net->dmz traffic needs to traverse.</para>
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<programlisting>#TARGET SOURCE DEST PROTO DEST SOURCE ORIGINAL RATE
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# PORT PORT(S) DEST LIMIT
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ACCEPT $MIRRORS
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#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE</programlisting>
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</blockquote>
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</section>
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<section>
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<title>/etc/shorewall/action.Drop</title>
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<blockquote>
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<para>This is my common action for the DROP policy. It is like the
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standard <emphasis role="bold">Drop</emphasis> action except that it
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allows <quote>Ping</quote>.</para>
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<programlisting>#TARGET SOURCE DEST PROTO DEST SOURCE RATE USER/
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# PORT(S) PORT(S) LIMIT GROUP
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RejectAuth
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AllowPing
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dropBcast
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DropSMB
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DropUPnP
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dropNotSyn
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DropDNSrep</programlisting>
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</blockquote>
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</section>
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<section>
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<title>/etc/shorewall/action.Reject</title>
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<blockquote>
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<para>This is my common action for the REJECT policy. It is like the
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standard <emphasis role="bold">Reject</emphasis> action except that it
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allows <quote>Ping</quote> and contains one rule that guards against
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log flooding by broken software running in my local zone.</para>
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<programlisting>#TARGET SOURCE DEST PROTO DEST SOURCE RATE USER/
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# PORT(S) PORT(S) LIMIT GROUP
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RejectAuth
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AllowPing
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dropBcast
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RejectSMB
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DropUPnP
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dropNotSyn
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DropDNSrep
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DROP loc:eth2:!192.168.1.0/24 #So that my braindead Windows[tm] XP system doesn't flood my log
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#with NTP requests with a source address in 16.0.0.0/8 (address of
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#its PPTP tunnel to HP).</programlisting>
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</blockquote>
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</section>
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<section>
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<title>Rules File (The shell variables are set in /etc/shorewall/params)</title>
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<blockquote>
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<programlisting>###############################################################################################################################################################################
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#RESULT CLIENT(S) SERVER(S) PROTO PORT(S) CLIENT ORIGINAL RATE USER
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# PORT(S) DEST:SNAT SET
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###############################################################################################################################################################################
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# Local Network to Internet - Reject attempts by Trojans to call home, direct SMTP and MS Message Service
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#
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RejectSMTP loc net tcp 25
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REJECT:$LOG loc net tcp 6667,25
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REJECT:$LOG loc net udp 1025:1031
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#
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# Stop NETBIOS crap since our policy is ACCEPT
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#
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REJECT loc net tcp 137,445
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REJECT loc net udp 137:139
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#
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DROP loc:!192.168.1.0/24 net
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#QUEUE loc net udp
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#QUEUE loc fw udp
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#QUEUE loc net tcp
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###############################################################################################################################################################################
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# Local Network to Firewall
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#
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DROP loc:!192.168.1.0/24 fw
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ACCEPT loc fw tcp ssh,time
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ACCEPT loc fw udp 161,ntp
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###############################################################################################################################################################################
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# Local Network to DMZ
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#
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DROP loc:!192.168.1.0/24 dmz
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ACCEPT loc dmz udp domain,xdmcp
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ACCEPT loc dmz tcp www,smtp,smtps,domain,ssh,imap,https,imaps,cvspserver,ftp,10027,pop3 -
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###############################################################################################################################################################################
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# Internet to ALL -- drop NewNotSyn packets
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#
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dropNotSyn net fw tcp
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dropNotSyn net loc tcp
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dropNotSyn net dmz tcp
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###############################################################################################################################################################################
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# Internet to DMZ
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#
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DNAT- net dmz:206.124.146.177 tcp smtp - 206.124.146.179,206.124.146.178
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ACCEPT net dmz tcp smtp,smtps,www,ftp,imaps,domain,https,cvspserver -
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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'm "on the road", the following two rules allow me VPN access back home.
|
|
#
|
|
DNAT net loc:192.168.1.4 tcp 1723 -
|
|
DNAT net:!4.3.113.178 loc:192.168.1.4 gre -
|
|
ACCEPT net loc:192.168.1.5 tcp 22
|
|
#
|
|
# 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
|
|
#
|
|
# Silently Handle common probes
|
|
#
|
|
REJECT net loc tcp www,ftp,https
|
|
###############################################################################################################################################################################
|
|
# DMZ to Internet
|
|
#
|
|
ACCEPT dmz net tcp smtp,domain,www,81,https,whois,echo,2702,21,2703,ssh,8080
|
|
ACCEPT dmz net udp domain
|
|
REJECT:$LOG dmz net udp 1025:1031
|
|
ACCEPT dmz net:$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't understand. Either way,
|
|
# the following works around the problem.
|
|
#
|
|
ACCEPT:$LOG dmz net tcp 1024: 20
|
|
###############################################################################################################################################################################
|
|
# DMZ to Firewall -- ntp & snmp, Silently reject Auth
|
|
#
|
|
ACCEPT dmz fw udp ntp ntp
|
|
ACCEPT dmz fw tcp 161,ssh
|
|
ACCEPT dmz fw udp 161
|
|
REJECT dmz fw tcp auth
|
|
###############################################################################################################################################################################
|
|
# DMZ to Local Network
|
|
#
|
|
ACCEPT dmz loc tcp smtp,6001:6010
|
|
ACCEPT dmz:206.124.146.177 loc:192.168.1.3 tcp 111
|
|
ACCEPT dmz:206.124.146.177 loc:192.168.1.3 udp
|
|
###############################################################################################################################################################################
|
|
# Internet to Firewall
|
|
#
|
|
REJECT net fw tcp www,ftp,https
|
|
ACCEPT net dmz udp 33434:33435
|
|
###############################################################################################################################################################################
|
|
# Firewall to Internet
|
|
#
|
|
ACCEPT fw net:$NTPSERVERS udp ntp ntp
|
|
#ACCEPT fw net:$POPSERVERS tcp pop3
|
|
ACCEPT fw net udp domain
|
|
ACCEPT fw net tcp domain,www,https,ssh,1723,whois,1863,ftp,2702,2703,7
|
|
ACCEPT fw net udp 33435:33535
|
|
ACCEPT fw net icmp
|
|
REJECT:$LOG fw net udp 1025:1031
|
|
DROP fw net udp ntp
|
|
###############################################################################################################################################################################
|
|
# 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
|
|
###############################################################################################################################################################################
|
|
ACCEPT tx loc:192.168.1.5 all
|
|
#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 entries(which is
|
|
displayed in <emphasis role="bold">bold type</emphasis>) add a route
|
|
to my DSL modem when eth0 is brought up and 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 auto eth0
|
|
iface eth0 inet static
|
|
address 206.124.146.176
|
|
netmask 255.255.255.0
|
|
network 206.124.146.0
|
|
broadcast 206.124.146.255
|
|
gateway 206.124.146.254
|
|
<emphasis role="bold">up ip route add 192.168.1.1 dev eth0</emphasis>
|
|
|
|
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's view of the
|
|
network is diagrammed in the following figure.</para>
|
|
|
|
<graphic fileref="images/network1.png" />
|
|
|
|
<para>I'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'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 "Stopping Bridge"
|
|
brctl delbr br0
|
|
ip link set eth0 down
|
|
ip link set eth1 down
|
|
ip link set eth2 down
|
|
}
|
|
|
|
do_start() {
|
|
|
|
echo "Starting Bridge"
|
|
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 "$1" in
|
|
start)
|
|
do_start
|
|
;;
|
|
stop)
|
|
do_stop
|
|
;;
|
|
restart)
|
|
do_stop
|
|
sleep 1
|
|
do_start
|
|
;;
|
|
*)
|
|
echo "Usage: $0 {start|stop|restart}"
|
|
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='static'
|
|
BROADCAST='192.168.1.255'
|
|
IPADDR='192.168.1.3'
|
|
NETWORK='192.168.1.0'
|
|
NETMASK='255.255.255.0'
|
|
REMOTE_IPADDR=''
|
|
STARTMODE='onboot'
|
|
UNIQUE='3hqH.MjuOqWfSZ+C'
|
|
WIRELESS='no'
|
|
MTU=''</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> |