forked from extern/shorewall_code
e1fe99db63
git-svn-id: https://shorewall.svn.sourceforge.net/svnroot/shorewall/trunk@4644 fbd18981-670d-0410-9b5c-8dc0c1a9a2bb
898 lines
38 KiB
XML
898 lines
38 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>Strong Firewall in a Routed Xen Dom0</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><?dbtimestamp format="Y/m/d"?></pubdate>
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<copyright>
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<year>2006</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
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License</ulink></quote>.</para>
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</legalnotice>
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</articleinfo>
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<caution>
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<para>This article applies to Shorewall 3.0 and later. If you are running
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a version of Shorewall earlier than Shorewall 3.0.0 then please see the
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documentation for that release.</para>
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</caution>
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<section>
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<title>Before Xen</title>
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<para>Prior to adopting <ulink url="Xen.html">Xen</ulink>, I had a home
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office crowded with 5 systems, three monitors a scanner and a printer. The
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systems were:</para>
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<orderedlist>
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<listitem>
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<para>Firewall</para>
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</listitem>
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<listitem>
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<para>Public Server in a DMZ (mail)</para>
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</listitem>
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<listitem>
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<para>Private Server (wookie)</para>
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</listitem>
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<listitem>
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<para>My personal Linux Desktop (ursa)</para>
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</listitem>
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<listitem>
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<para>My work system (docked laptop running Windows XP).</para>
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</listitem>
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</orderedlist>
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<para>The result was a very crowded and noisy room.</para>
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</section>
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<section>
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<title>After Xen</title>
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<para>Xen has allowed me to reduce the noise and clutter considerably. I
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now have three systems with two monitors. I've also replaced the
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individual printer and scanner with a Multifunction
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FAX/Scanner/Printer.</para>
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<para>The systems now include:</para>
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<orderedlist>
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<listitem>
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<para>Combination Firewall/Public Server/Private Server/Wireless
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Gateway using Xen (created by building out my Linux desktop
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system).</para>
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</listitem>
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<listitem>
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<para>My work system.</para>
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</listitem>
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<listitem>
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<para>My Linux desktop (wookie, which is actually the old public
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server box)</para>
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</listitem>
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</orderedlist>
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<para>Most of the Linux systems run <trademark>SuSE </trademark>10.1; my
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personal Linux desktop system and our Linux Laptop run
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<trademark>Ubuntu</trademark> "Dapper Drake".</para>
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<para>If you are unfamiliar with Xen networking, I recommend that you read
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the first section of the companion <ulink url="Xen.html">Xen and
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Shorewall</ulink> article.</para>
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<para>Here is a high-level diagram of our network.</para>
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<graphic align="center" fileref="images/Xen5.png" />
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<para>As shown in this diagram, the Xen system has three physical network
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interfaces. These are:</para>
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<itemizedlist>
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<listitem>
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<para><filename class="devicefile">eth0</filename> -- connected to our
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DSL "Modem".</para>
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</listitem>
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<listitem>
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<para><filename class="devicefile">eth1</filename> -- connected to the
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switch in my office. That switch is cabled to a second switch in my
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wife's office where my wife has her desktop and networked printer (I
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sure wish that there had been wireless back when I strung that CAT-5
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cable halfway across the house).</para>
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</listitem>
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<listitem>
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<para><filename class="devicefile">eth2</filename> -- connected to a
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Wireless Access Point (WAP) that interfaces to our wireless
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network.</para>
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</listitem>
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</itemizedlist>
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<para>There are Two Xen domains.</para>
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<orderedlist>
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<listitem>
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<para>Dom0 (DNS name gateway.shorewall.net) is used as our main
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firewall and wireless gateway as well as a local file server.</para>
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</listitem>
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<listitem>
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<para>The DomU (Dom name <emphasis role="bold">lists</emphasis>, DNS
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name lists.shorewall.net) is used as a public Web/FTP/Mail/DNS
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server.</para>
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</listitem>
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</orderedlist>
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<para>Shorewall runs in Dom0.</para>
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<caution>
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<para>As the developer of Shorewall, I have enough experience to be very
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comfortable with Linux networking and Shorewall/iptables. I arrived at
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this configuration after a fair amount of trial and error
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experimentation (see <ulink url="Xen.html">Xen and Shorewall</ulink> and
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<ulink url="XenMyWay.html">Xen and the art of Consolidation</ulink>). If
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you are a Linux networking novice, I recommend that you do not attempt a
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configuration like this one for your first Shorewall installation. You
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are very likely to frustrate both yourself and the Shorewall support
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team. Rather I suggest that you start with something simple like a
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<ulink url="standalone.htm">standalone installation</ulink> in a domU;
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once you are comfortable with that then you will be ready to try
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something more substantial.</para>
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<para>As Paul Gear says: <emphasis>Shorewall might make iptables easy,
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but it doesn't make understanding fundamental networking principles,
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traffic shaping, or multi-ISP routing any easier</emphasis>.</para>
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<para>The same goes for Xen networking.</para>
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</caution>
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<section id="Domains">
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<title>Domain Configuration</title>
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<para>Below are the relevant configuration files for the three domains.
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I use partitions on my hard drives for DomU storage devices.</para>
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<blockquote>
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<para><filename>/boot/grub/menu.lst</filename> — here is the entry
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that boots Xen in Dom0.</para>
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<programlisting>title XEN
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root (hd0,1)
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kernel /boot/xen.gz dom0_mem=458752 sched=bvt
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module /boot/vmlinuz-xen root=/dev/hda2 vga=0x31a selinux=0 resume=/dev/hda1 splash=silent showopts
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module /boot/initrd-xen</programlisting>
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<para><filename>/etc/modprobe.conf.local</filename></para>
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<programlisting>options netloop nloopbacks=1 #Stop netloop from creating 8 vifs</programlisting>
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<para><filename>/etc/xen/auto/02-lists</filename> — configuration file
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for the lists domain. Note that the vifname is set to 'eth3' for the
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virtual interface to this vm.</para>
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<programlisting># -*- mode: python; -*-
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# configuration name:
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name = "lists"
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# usable ram:
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memory = 512
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# kernel and initrd:
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kernel = "/xen2/vmlinuz-xen"
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ramdisk = "/xen2/initrd-xen"
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# boot device:
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root = "/dev/hda3"
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# boot to run level:
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extra = "3"
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# network interface:
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vif = [ 'mac=aa:cc:00:00:00:01, ip=206.124.146.177, vifname=eth3' ]
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# storage devices:
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disk = [ 'phy:hda3,hda3,w' ]</programlisting>
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</blockquote>
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<para>With both Xen domains up and running, the system looks as shown in
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the following diagram.</para>
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<graphic align="center" fileref="images/Xen4a.png" />
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<para>The zones correspond to the Shorewall zones in the firewall Dom0
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configuration.</para>
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<caution>
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<para>Under some circumstances, UDP and/or TCP communication from a
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domU won't work for no obvious reason. That happened with the
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<emphasis role="bold">lists</emphasis> domain in my setup. Looking at
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the IP traffic with <command>tcpdump -nvvi eth1</command> in the
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<emphasis role="bold">firewall</emphasis> domU showed that UDP packets
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from the <emphasis role="bold">lists</emphasis> domU had incorrect
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checksums. That problem was corrected by arranging for the following
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command to be executed in the <emphasis role="bold">lists</emphasis>
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domain when its <filename class="devicefile">eth0</filename> device
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was brought up:</para>
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<para><command>ethtool -K eth0 tx off</command></para>
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<para>Under SuSE 10.1, I placed the following in
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<filename>/etc/sysconfig/network/if-up.d/resettx</filename> (that file
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is executable):</para>
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<programlisting>#!/bin/sh
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if [ $2 = eth0 ]; then
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ethtool -K eth0 tx off
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echo "TX Checksum reset on eth0"
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fi</programlisting>
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<para>Under other distributions, the technique will vary. For example,
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under <trademark>Debian</trademark> or <trademark>Ubuntu</trademark>,
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you can just add a 'post-up' entry to
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<filename>/etc/network/interfaces</filename> as shown here:</para>
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<programlisting> iface eth0 inet static
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address 206.124.146.177
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netmask 255.255.255.0
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post-up ethtool -K eth0 tx off</programlisting>
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</caution>
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</section>
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<section id="Firewall">
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<title>Firewall Dom0 Configuration</title>
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<para>In the firewall Dom0, I run a conventional three-interface
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firewall with Proxy ARP DMZ -- it is very similar to the firewall
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described in the <ulink url="shorewall_setup_guide.htm">Shorewall Setup
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Guide</ulink> with the exception that I've added a fourth interface for
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our wireless network. The firewall runs a routed <ulink
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url="OPENVPN.html">OpenVPN server</ulink> to provide roadwarrior access
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for our two laptops and a bridged OpenVPN server for the wireless
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network in our home. Here is the firewall's view of the network:</para>
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<graphic align="center" fileref="images/network4a.png" />
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<para>The two laptops can be directly attached to the LAN as shown above
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or they can be attached wirelessly -- their IP addresses are the same in
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either case; when they are directly attached, the IP address is assigned
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by the DHCP server running in Dom0 and when they are attached
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wirelessly, the IP address is assigned by OpenVPN.</para>
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<para>The Shorewall configuration files are shown below. All routing and
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secondary IP addresses are handled in the SUSE network
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configuration.</para>
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<blockquote>
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<para>/etc/shorewall/shorewall.conf</para>
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<programlisting>STARTUP_ENABLED=Yes
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VERBOSITY=0
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LOGFILE=/var/log/firewall
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LOGFORMAT="FW:%s:%s:"
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LOGTAGONLY=No
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LOGRATE=
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LOGBURST=
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LOGALLNEW=
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BLACKLIST_LOGLEVEL=
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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=$LOG
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LOG_MARTIANS=No
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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=/var/lock/subsys/shorewall-lite
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MODULESDIR=
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CONFIG_PATH=/usr/share/shorewall-lite:/usr/share/shorewall/configfiles:/usr/share/shorewall
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RESTOREFILE=restore
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IPSECFILE=zones
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IP_FORWARDING=On
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ADD_IP_ALIASES=No
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ADD_SNAT_ALIASES=No
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RETAIN_ALIASES=No
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TC_ENABLED=Internal
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TC_EXPERT=No
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CLEAR_TC=Yes
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MARK_IN_FORWARD_CHAIN=Yes
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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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ADMINISABSENTMINDED=Yes
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BLACKLISTNEWONLY=Yes
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DELAYBLACKLISTLOAD=Yes
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MODULE_SUFFIX=
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DISABLE_IPV6=Yes
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BRIDGING=No
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DYNAMIC_ZONES=No
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PKTTYPE=No
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RFC1918_STRICT=Yes
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MACLIST_TTL=60
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SAVE_IPSETS=No
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MAPOLDACTIONS=No
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FASTACCEPT=Yes
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HIGH_ROUTE_MARKS=Yes
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BLACKLIST_DISPOSITION=DROP
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MACLIST_TABLE=mangle
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MACLIST_DISPOSITION=DROP
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TCP_FLAGS_DISPOSITION=DROP</programlisting>
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<para><filename>/etc/shorewall/zones</filename>:</para>
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<programlisting>#ZONE TYPE OPTIONS IN OUT
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# OPTIONS OPTIONS
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fw firewall #The firewall itself.
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net ipv4 #Internet
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loc ipv4 #Local wired Zone
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dmz ipv4 #DMZ
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vpn ipv4 #Open VPN clients
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wifi ipv4 #Local Wireless Zone
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#LAST LINE - ADD YOUR ENTRIES ABOVE THIS ONE - DO NOT REMOVE
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</programlisting>
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<para><filename>/etc/shorewall/policy</filename>:</para>
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<programlisting>#SOURCE DEST POLICY LOG LIMIT:BURST
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# LEVEL
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$FW $FW ACCEPT
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$FW net ACCEPT
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loc net ACCEPT
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$FW vpn ACCEPT
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vpn net ACCEPT
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vpn loc ACCEPT
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loc vpn ACCEPT
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$FW loc ACCEPT
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loc $FW ACCEPT
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wifi all REJECT $LOG
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net $FW DROP $LOG 1/sec:2
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net loc DROP $LOG 2/sec:4
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net dmz DROP $LOG 8/sec:30
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net vpn DROP $LOG
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all all REJECT $LOG
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#LAST LINE -- DO NOT REMOVE</programlisting>
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<para><filename>Note that the firewall<->local network interface
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is wide open so from a security point of view, the firewall system is
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part of the local zone.</filename></para>
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<para><filename>/etc/shorewall/params (edited)</filename>:</para>
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<programlisting>MIRRORS=<comma-separated list of Shorewall mirrors>
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NTPSERVERS=<comma-separated list of NTP servers I sync with>
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POPSERVERS=<comma-separated list of server IP addresses>
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LOG=info
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INT_IF=br0
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DMZ_IF=eth3
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EXT_IF=eth0
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WIFI_IF=eth2
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OMAK=<IP address at our second home>
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#LAST LINE - ADD YOUR ENTRIES ABOVE THIS ONE - DO NOT REMOVE</programlisting>
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<para><filename>/etc/shorewall/init</filename>:</para>
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<programlisting>echo 1 > /proc/sys/net/ipv4/netfilter/ip_conntrack_tcp_be_liberal</programlisting>
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<para><filename>/etc/shorewall/interfaces</filename>:</para>
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<programlisting>#ZONE INTERFACE BROADCAST OPTIONS
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net $EXT_IF 206.124.146.255 dhcp,norfc1918,logmartians,blacklist,tcpflags,nosmurfs
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dmz $DMZ_IF 192.168.0.255 logmartians
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loc $INT_IF 192.168.1.255 dhcp,routeback,logmartians
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wifi $WIFI_IF 192.168.3.255 dhcp,maclist
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vpn tun+ -
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#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE</programlisting>
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<para><filename>/etc/shorewall/nat</filename>:</para>
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<programlisting>#EXTERNAL INTERFACE INTERNAL ALL LOCAL
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# INTERFACES
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206.124.146.178 $EXT_IF 192.168.1.3 No No #Wookie
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206.124.146.180 $EXT_IF 192.168.1.6 No No #Work LapTop
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#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS LINE -- DO NOT REMOVE</programlisting>
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<para><filename>/etc/shorewall/masq (Note the cute trick here and in
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the <filename>following proxyarp</filename> file that allows me to
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access the DSL "Modem" using it's default IP address
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(192.168.1.1))</filename>. The leading "+" is required to place the
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rule before the SNAT rules generated by entries in
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<filename>/etc/shorewall/nat</filename> above.</para>
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<programlisting>#INTERFACE SUBNET ADDRESS PROTO PORT(S) IPSEC
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+$EXT_IF:192.168.1.1 0.0.0.0/0 192.168.1.254
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$EXT_IF 192.168.0.0/22 206.124.146.179
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#LAST LINE -- ADD YOUR ENTRIES ABOVE THIS LINE -- DO NOT REMOVE</programlisting>
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<para><filename>/etc/shorewall/proxyarp</filename>:</para>
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<programlisting>#ADDRESS INTERFACE EXTERNAL HAVEROUTE PERSISTENT
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192.168.1.1 $EXT_IF $INT_IF yes
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206.124.146.177 $DMZ_IF $EXT_IF yes
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#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE</programlisting>
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<para><filename>/etc/shorewall/tunnels</filename>:</para>
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<programlisting>#TYPE ZONE GATEWAY GATEWAY
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# ZONE
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openvpnserver:udp net 0.0.0.0/0 #Routed server for RoadWarrior access
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openvpnserver:udp wifi 192.168.3.0/24 #Home wireless network server
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#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE</programlisting>
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<para><filename>/etc/shorewall/actions</filename>:</para>
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<programlisting>#ACTION
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Mirrors # Accept traffic from Shorewall Mirrors
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#LAST LINE - ADD YOUR ENTRIES ABOVE THIS ONE - DO NOT REMOVE</programlisting>
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<para><filename>/etc/shorewall/action.Mirrors</filename>:</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 $MIRRORS
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#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE</programlisting>
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<para><filename>/etc/shorewall/rules</filename>:</para>
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<programlisting>SECTION NEW
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###############################################################################################################################################################################
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#ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL RATE USER/
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# PORT PORT(S) DEST LIMIT GROUP
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###############################################################################################################################################################################
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REJECT:$LOG loc net tcp 25
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REJECT:$LOG loc net udp 1025:1031
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#
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# Stop NETBIOS crap
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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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# Stop my idiotic work laptop from sending to the net with an HP source/dest IP address
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|
#
|
|
DROP loc:!192.168.0.0/22 net
|
|
###############################################################################################################################################################################
|
|
# Local Network to Firewall
|
|
#
|
|
REDIRECT- loc 3128 tcp 80 - !192.168.1.1,192.168.0.7,206.124.146.177,155.98.64.80
|
|
###############################################################################################################################################################################
|
|
# Road Warriors to Firewall
|
|
#
|
|
ACCEPT vpn fw tcp ssh,time,631,8080
|
|
ACCEPT vpn fw udp 161,ntp,631
|
|
Ping/ACCEPT vpn fw
|
|
###############################################################################################################################################################################
|
|
# Road Warriors to DMZ
|
|
#
|
|
ACCEPT vpn dmz udp domain
|
|
ACCEPT vpn dmz tcp www,smtp,smtps,domain,ssh,imap,https,imaps,ftp,10023,pop3 -
|
|
Ping/ACCEPT vpn dmz
|
|
###############################################################################################################################################################################
|
|
# Local network to DMZ
|
|
#
|
|
ACCEPT loc dmz udp domain
|
|
ACCEPT loc dmz tcp ssh,smtps,www,ftp,imaps,domain,https -
|
|
ACCEPT loc dmz tcp smtp
|
|
Trcrt/ACCEPT loc dmz
|
|
###############################################################################################################################################################################
|
|
# Internet to ALL -- drop NewNotSyn packets
|
|
#
|
|
dropNotSyn net fw tcp
|
|
#dropNotSyn net loc tcp
|
|
dropNotSyn net dmz tcp
|
|
###############################################################################################################################################################################
|
|
# Internet to DMZ
|
|
#
|
|
ACCEPT net dmz udp domain
|
|
LOG:$LOG net:64.126.128.0/18 dmz tcp smtp
|
|
ACCEPT net dmz tcp smtps,www,ftp,imaps,domain,https -
|
|
ACCEPT net dmz tcp smtp - 206.124.146.177,206.124.146.178
|
|
ACCEPT net dmz udp 33434:33454
|
|
Mirrors net dmz tcp rsync
|
|
Limit:$LOG:SSHA,3,60\
|
|
net dmz tcp 22
|
|
Trcrt/ACCEPT net dmz
|
|
##############################################################################################################################################################################
|
|
#
|
|
# Net to Local
|
|
#
|
|
# When I'm "on the road", the following two rules allow me VPN access back home using PPTP.
|
|
#
|
|
DNAT net loc:192.168.1.4 tcp 1729
|
|
DNAT net loc:192.168.1.4 gre
|
|
#
|
|
# Roadwarrior access to Ursa
|
|
#
|
|
ACCEPT net:$OMAK loc tcp 22
|
|
Limit:$LOG:SSHA,3,60\
|
|
net loc tcp 22
|
|
|
|
#
|
|
# ICQ
|
|
#
|
|
ACCEPT net loc:192.168.1.3 tcp 113,4000:4100
|
|
#
|
|
# Bittorrent
|
|
#
|
|
ACCEPT net loc:192.168.1.3 tcp 6881:6889,6969
|
|
ACCEPT net loc:192.168.1.3 udp 6881:6889,6969
|
|
#
|
|
# Real Audio
|
|
#
|
|
ACCEPT net loc:192.168.1.3 udp 6970:7170
|
|
#
|
|
# Overnet
|
|
#
|
|
#ACCEPT net loc:192.168.1.3 tcp 4662
|
|
#ACCEPT net loc:192.168.1.3 udp 12112
|
|
#
|
|
# OpenVPN
|
|
#
|
|
ACCEPT net loc:192.168.1.3 udp 1194
|
|
ACCEPT net loc:192.168.1.6 udp 1194
|
|
# Skype
|
|
#
|
|
ACCEPT net loc:192.168.1.6 tcp 1194
|
|
#
|
|
# Traceroute
|
|
#
|
|
Trcrt/ACCEPT net loc:192.168.1.3
|
|
#
|
|
# Silently Handle common probes
|
|
#
|
|
REJECT net loc tcp www,ftp,https
|
|
DROP net loc icmp 8
|
|
###############################################################################################################################################################################
|
|
# DMZ to Internet
|
|
#
|
|
ACCEPT dmz net udp domain,ntp
|
|
ACCEPT dmz net tcp echo,ftp,ssh,smtp,whois,domain,www,81,https,cvspserver,2702,2703,8080
|
|
ACCEPT dmz net:$POPSERVERS tcp pop3
|
|
Ping/ACCEPT dmz net
|
|
#
|
|
# Some FTP clients seem prone to sending the PORT command split over two packets. This prevents the FTP connection tracking
|
|
# code from processing the command and setting up the proper expectation. The following rule allows active FTP to work in these cases
|
|
# but logs the connection so I can keep an eye on this potential security hole.
|
|
#
|
|
ACCEPT:$LOG dmz net tcp 1024: 20
|
|
###############################################################################################################################################################################
|
|
# Local to DMZ
|
|
#
|
|
ACCEPT loc dmz udp domain,xdmcp
|
|
ACCEPT loc dmz tcp www,smtp,smtps,domain,ssh,imap,rsync,https,imaps,ftp,10023,pop3,3128
|
|
Trcrt/ACCEPT loc dmz
|
|
###############################################################################################################################################################################
|
|
# DMZ to Local
|
|
#
|
|
ACCEPT dmz loc:192.168.1.5 udp 123
|
|
ACCEPT dmz loc:192.168.1.5 tcp 21
|
|
Ping/ACCEPT dmz loc
|
|
|
|
###############################################################################################################################################################################
|
|
# DMZ to Firewall -- ntp & snmp, Silently reject Auth
|
|
#
|
|
#ACCEPT net loc:192.168.1.3 udp 12112
|
|
#
|
|
# OpenVPN
|
|
#
|
|
ACCEPT net loc:192.168.1.3 udp 1194
|
|
ACCEPT net loc:192.168.1.6 udp 1194
|
|
# Skype
|
|
#
|
|
ACCEPT net loc:192.168.1.6 tcp 1194
|
|
#
|
|
# Traceroute
|
|
#
|
|
Trcrt/ACCEPT net loc:192.168.1.3
|
|
#
|
|
# Silently Handle common probes
|
|
#
|
|
REJECT net loc tcp www,ftp,https
|
|
DROP net loc icmp 8
|
|
###############################################################################################################################################################################
|
|
# DMZ to Internet
|
|
#
|
|
ACCEPT dmz net udp domain,ntp
|
|
ACCEPT dmz net tcp echo,ftp,ssh,smtp,whois,domain,www,81,https,cvspserver,2702,2703,8080
|
|
ACCEPT dmz net:$POPSERVERS tcp pop3
|
|
Ping/ACCEPT dmz net
|
|
#
|
|
# Some FTP clients seem prone to sending the PORT command split over two packets. This prevents the FTP connection tracking
|
|
# code from processing the command and setting up the proper expectation. The following rule allows active FTP to work in these cases
|
|
# but logs the connection so I can keep an eye on this potential security hole.
|
|
#
|
|
ACCEPT:$LOG dmz net tcp 1024: 20
|
|
###############################################################################################################################################################################
|
|
# Local to DMZ
|
|
#
|
|
ACCEPT loc dmz udp domain,xdmcp
|
|
ACCEPT loc dmz tcp www,smtp,smtps,domain,ssh,imap,rsync,https,imaps,ftp,10023,pop3,3128
|
|
Trcrt/ACCEPT loc dmz
|
|
###############################################################################################################################################################################
|
|
# DMZ to Local
|
|
#
|
|
ACCEPT dmz loc:192.168.1.5 udp 123
|
|
ACCEPT dmz loc:192.168.1.5 tcp 21
|
|
Ping/ACCEPT dmz loc
|
|
|
|
###############################################################################################################################################################################
|
|
# DMZ to Firewall -- ntp & snmp, Silently reject Auth
|
|
#
|
|
ACCEPT loc dmz udp domain,xdmcp
|
|
ACCEPT loc dmz tcp www,smtp,smtps,domain,ssh,imap,rsync,https,imaps,ftp,10023,pop3,3128
|
|
Trcrt/ACCEPT loc dmz
|
|
###############################################################################################################################################################################
|
|
# DMZ to Local
|
|
#
|
|
ACCEPT dmz loc:192.168.1.5 udp 123
|
|
ACCEPT dmz loc:192.168.1.5 tcp 21
|
|
Ping/ACCEPT dmz loc
|
|
|
|
###############################################################################################################################################################################
|
|
# DMZ to Firewall -- ntp & snmp, Silently reject Auth
|
|
#
|
|
ACCEPT dmz fw tcp 161,ssh
|
|
ACCEPT dmz fw udp 161,ntp
|
|
REJECT dmz fw tcp auth
|
|
Ping/ACCEPT dmz fw
|
|
###############################################################################################################################################################################
|
|
# Internet to Firewall
|
|
#
|
|
REJECT net fw tcp www,ftp,https
|
|
DROP net fw icmp 8
|
|
ACCEPT net fw udp 33434:33454
|
|
ACCEPT net:$OMAK fw udp ntp
|
|
ACCEPT net fw tcp auth
|
|
ACCEPT net:$OMAK fw tcp 22
|
|
Limit:$LOG:SSHA,3,60\
|
|
net fw tcp 22
|
|
Trcrt/ACCEPT net fw
|
|
#
|
|
# Bittorrent
|
|
#
|
|
ACCEPT net fw tcp 6881:6889,6969
|
|
ACCEPT net fw udp 6881:6889,6969
|
|
###############################################################################################################################################################################
|
|
# Firewall to DMZ
|
|
#
|
|
ACCEPT fw dmz tcp domain,www,ftp,ssh,smtp,https,993,465
|
|
ACCEPT fw dmz udp domain
|
|
REJECT fw dmz udp 137:139
|
|
Ping/ACCEPT fw dmz
|
|
##############################################################################################################################################################################
|
|
# Avoid logging Freenode.net probes
|
|
#
|
|
DROP net:82.96.96.3 all
|
|
#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE</programlisting>
|
|
|
|
<para><filename>/etc/shorewall/tcdevices</filename></para>
|
|
|
|
<programlisting>#INTERFACE IN-BANDWITH OUT-BANDWIDTH
|
|
$EXT_IF 1.3mbit 384kbit
|
|
#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE
|
|
</programlisting>
|
|
|
|
<para><filename>/etc/shorewall/tcclasses</filename><programlisting>#INTERFACE MARK RATE CEIL PRIORITY OPTIONS
|
|
$EXT_IF 10 full full 1 tcp-ack,tos-minimize-delay
|
|
$EXT_IF 20 9*full/10 9*full/10 2 default
|
|
$EXT_IF 30 6*full/10 6*full/10 3
|
|
#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE</programlisting></para>
|
|
|
|
<para><filename>/etc/shorewall/tcrules</filename><programlisting>#MARK SOURCE DEST PROTO PORT(S) CLIENT USER TEST
|
|
# PORT(S)
|
|
1:110 192.168.0.0/22 $EXT_IF #Our internel nets get priority
|
|
#over the server
|
|
1:130 206.124.146.177 $EXT_IF tcp - 873 #Throttle rsync traffic to the
|
|
#Shorewall Mirrors.
|
|
#LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE</programlisting></para>
|
|
</blockquote>
|
|
|
|
<para>The tap0 device used by the bridged OpenVPN server is created and
|
|
bridged to eth1 using a SuSE-specific SysV init script:</para>
|
|
|
|
<blockquote>
|
|
<programlisting>#!/bin/sh
|
|
#
|
|
# The Shoreline Firewall (Shorewall) Packet Filtering Firewall - V3.0
|
|
#
|
|
# This program is under GPL [http://www.gnu.org/copyleft/gpl.htm]
|
|
#
|
|
# (c) 1999,2000,2001,2002,2003,2004,2005 - Tom Eastep (teastep@shorewall.net)
|
|
#
|
|
# On most distributions, this file should be called /etc/init.d/shorewall.
|
|
#
|
|
# Complete documentation is available at http://shorewall.net
|
|
#
|
|
# This program is free software; you can redistribute it and/or modify
|
|
# it under the terms of Version 2 of the GNU General Public License
|
|
# as published by the Free Software Foundation.
|
|
#
|
|
# This program is distributed in the hope that it will be useful,
|
|
# but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
# GNU General Public License for more details.
|
|
#
|
|
# You should have received a copy of the GNU General Public License
|
|
# along with this program; if not, write to the Free Software
|
|
# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA
|
|
#
|
|
# If an error occurs while starting or restarting the firewall, the
|
|
# firewall is automatically stopped.
|
|
#
|
|
# Commands are:
|
|
#
|
|
# bridge start Starts the bridge
|
|
# bridge restart Restarts the bridge
|
|
# bridge reload Restarts the bridge
|
|
# bridge stop Stops the bridge
|
|
# bridge status Displays bridge status
|
|
#
|
|
|
|
# chkconfig: 2345 4 99
|
|
# description: Packet filtering firewall
|
|
|
|
### BEGIN INIT INFO
|
|
# Provides: bridge
|
|
# Required-Start: boot.udev
|
|
# Required-Stop:
|
|
# Default-Start: 2 3 5
|
|
# Default-Stop: 0 1 6
|
|
# Description: starts and stops the bridge
|
|
### END INIT INFO
|
|
|
|
################################################################################
|
|
# Interfaces to be bridged -- may be listed by device name or by MAC
|
|
#
|
|
INTERFACES="eth1"
|
|
|
|
#
|
|
# Tap Devices
|
|
#
|
|
TAPS="tap0"
|
|
|
|
################################################################################
|
|
# Give Usage Information #
|
|
################################################################################
|
|
usage() {
|
|
echo "Usage: $0 start|stop|reload|restart|status"
|
|
exit 1
|
|
}
|
|
#################################################################################
|
|
# Find the interface with the passed MAC address
|
|
#################################################################################
|
|
find_interface_by_mac() {
|
|
local mac=$1 first second rest dev
|
|
|
|
/sbin/ip link ls | while read first second rest; do
|
|
case $first in
|
|
*:)
|
|
dev=$second
|
|
;;
|
|
*)
|
|
if [ "$second" = $mac ]; then
|
|
echo ${dev%:}
|
|
return
|
|
fi
|
|
esac
|
|
done
|
|
}
|
|
################################################################################
|
|
# Convert MAC addresses to interface names
|
|
################################################################################
|
|
get_interfaces() {
|
|
local interfaces= interface
|
|
|
|
for interface in $INTERFACES; do
|
|
case $interface in
|
|
*:*:*)
|
|
interface=$(find_interface_by_mac $interface)
|
|
[ -n "$interface" ] || echo "WARNING: Can't find an interface with MAC address $mac"
|
|
;;
|
|
esac
|
|
interfaces="$interfaces $interface"
|
|
done
|
|
|
|
INTERFACES="$interfaces"
|
|
}
|
|
################################################################################
|
|
# Start the Bridge
|
|
################################################################################
|
|
do_start()
|
|
{
|
|
local interface
|
|
|
|
get_interfaces
|
|
|
|
for interface in $TAPS; do
|
|
/usr/sbin/openvpn --mktun --dev $interface
|
|
done
|
|
|
|
/sbin/brctl addbr br0
|
|
|
|
for interface in $INTERFACES $TAPS; do
|
|
/sbin/ip link set $interface up
|
|
/sbin/brctl addif br0 $interface
|
|
done
|
|
}
|
|
################################################################################
|
|
# Stop the Bridge
|
|
################################################################################
|
|
do_stop()
|
|
{
|
|
local interface
|
|
|
|
get_interfaces
|
|
|
|
for interface in $INTERFACES $TAPS; do
|
|
/sbin/brctl delif br0 $interface
|
|
/sbin/ip link set $interface down
|
|
done
|
|
|
|
/sbin/ip link set br0 down
|
|
|
|
/sbin/brctl delbr br0
|
|
|
|
for interface in $TAPS; do
|
|
/usr/sbin/openvpn --rmtun --dev $interface
|
|
done
|
|
}
|
|
################################################################################
|
|
# E X E C U T I O N B E G I N S H E R E #
|
|
################################################################################
|
|
command="$1"
|
|
|
|
case "$command" in
|
|
start)
|
|
do_start
|
|
;;
|
|
stop)
|
|
do_stop
|
|
;;
|
|
restart|reload)
|
|
do_stop
|
|
do_start
|
|
;;
|
|
status)
|
|
/sbin/brctl show
|
|
;;
|
|
*)
|
|
usage
|
|
;;
|
|
esac
|
|
</programlisting>
|
|
</blockquote>
|
|
</section>
|
|
</section>
|
|
</article> |