1
0
mirror of https://gitlab.com/shorewall/code.git synced 2024-12-21 22:01:57 +01:00
shorewall_code/docs/Dynamic.xml
Tom Eastep 44599530ea Remove warnings about duplicate zone/interface dynamic hosts
Signed-off-by: Tom Eastep <teastep@shorewall.net>
2011-06-20 18:27:18 -07:00

307 lines
9.9 KiB
XML

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE article PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN"
"http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd">
<article>
<!--$Id$-->
<articleinfo>
<title>Dynamic Zones</title>
<authorgroup>
<author>
<firstname>Tom</firstname>
<surname>Eastep</surname>
</author>
</authorgroup>
<pubdate><?dbtimestamp format="Y/m/d"?></pubdate>
<copyright>
<year>2009</year>
<holder>Thomas M. Eastep</holder>
</copyright>
<legalnotice>
<para>Permission is granted to copy, distribute and/or modify this
document under the terms of the GNU Free Documentation License, Version
1.2 or any later version published by the Free Software Foundation; with
no Invariant Sections, with no Front-Cover, and with no Back-Cover
Texts. A copy of the license is included in the section entitled
<quote><ulink url="GnuCopyright.htm">GNU Free Documentation
License</ulink></quote>.</para>
</legalnotice>
</articleinfo>
<section>
<title>Overview</title>
<para>There is sometimes a need to be able to define a zone whose members
are unknown at compile-time. For example, you may wish to require
authentication of internal users before allowing them access to the
internet. When a user is authenticated, the user's IP address is added to
the zone of users permitted web access.</para>
<para>Shorewall provides basic support for defining such zones. This
support is based on <ulink
url="http://ipset.netfilter.org/">ipset</ulink>. As of this writing, ipset
is not included in the standard kernel distribution; so to use dynamic
zones, you must be running kernel 2.6.20 or later and have installed the
<ulink
url="http://xtables-addons.sourceforge.net/">xtables-addons</ulink>.</para>
</section>
<section id="xtables-addons">
<title>Installing xtables-addons</title>
<para>The xtables-addons are fairly easy to install. You do not need to
recompile your kernel.</para>
<para><trademark>Debian</trademark> users can find xtables-addons-common
and xtables-addons-source packages in <firstterm>testing</firstterm>. The
kernel modules can be built and installed with the help of
module-assistant. As of this writing, these packages are in the
<firstterm>admin</firstterm> group rather than in the
<firstterm>network</firstterm> group!!??</para>
<para>For other users, the basic steps are as follows:</para>
<orderedlist>
<listitem>
<para>Install gcc and make</para>
</listitem>
<listitem>
<para>Install the headers for the kernel you are running. In some
distributions, such as <trademark>Debian</trademark> and
<trademark>Ubuntu</trademark>, the packet is called kernel-headers.
For other distrubutions, such as OpenSuSE, you must install the
kernel-source package.</para>
</listitem>
<listitem>
<para>download the iptables source tarball</para>
</listitem>
<listitem>
<para>untar the source</para>
</listitem>
<listitem>
<para>cd to the iptables source directory</para>
</listitem>
<listitem>
<para>run 'make'</para>
</listitem>
<listitem>
<para>as root, run 'make install'</para>
</listitem>
<listitem>
<para>Your new iptables binary will now be installed in
/usr/local/sbin. Modify shorewall.conf to specify
IPTABLES=/usr/local/sbin/iptables</para>
</listitem>
<listitem>
<para>Download the latest xtables-addons source tarball</para>
</listitem>
<listitem>
<para>Untar the xtables-addons source</para>
</listitem>
<listitem>
<para>cd to the xtables-addons source directory</para>
</listitem>
<listitem>
<para>run './configure'</para>
</listitem>
<listitem>
<para>run 'make'</para>
</listitem>
<listitem>
<para>As root, cd to the xtables-addons directory and run 'make
install'.</para>
</listitem>
<listitem>
<para>Restart shorewall</para>
</listitem>
<listitem>
<para>'shorewall show capabilities' should now indicate<emphasis
role="bold"> Ipset Match: Available</emphasis></para>
</listitem>
</orderedlist>
<para>You will have to repeat steps 10-13 each time that you receive a
kernel upgrade from your distribution vendor. You can install
xtables-addons before booting to the new kernel as follows
(<emphasis>new-kernel-version</emphasis> is the version of the
newly-installed kernel - example <emphasis
role="bold">2.6.28.11-generic</emphasis>. Look in the /lib/modules
directory to get the full version name)</para>
<orderedlist>
<listitem>
<para>cd to the xtables-addons source directory</para>
</listitem>
<listitem>
<para>run 'make clean'</para>
</listitem>
<listitem>
<para>run './configure
--with-kbuild=/lib/modules/<emphasis>new-kernel-version</emphasis>/build
--with-ksource=/lib/modules/<emphasis>new-kernel-version</emphasis>/source'</para>
</listitem>
<listitem>
<para>run 'make'</para>
</listitem>
<listitem>
<para>As root, cd to the xtables-addons source directory and run 'make
install'.</para>
</listitem>
<listitem>
<para>As root, run 'depmod -a
<emphasis>new-kernel-version'</emphasis></para>
</listitem>
</orderedlist>
</section>
<section id="defining">
<title>Defining a Dynamic Zone</title>
<para>A dynamic zone is defined by using the keyword dynamic in the zones
host list.</para>
<para>Example:</para>
<blockquote>
<para><filename>/etc/shorewall/zones</filename>:<programlisting>#NAME TYPE OPTIONS
loc ipv4
webok:loc ipv4</programlisting><filename>/etc/shorewall/interfaces</filename>:</para>
<programlisting>#ZONE INTERFACE BROADCAST OPTIONS
loc eth0 - …
</programlisting>
<para><filename>/etc/shorewall/hosts</filename>:</para>
<programlisting>#ZONE HOSTS OPTIONS
webok eth0:dynamic</programlisting>
</blockquote>
<para>Once the above definition is added, Shorewall will automatically
create an ipset named <emphasis>webok_eth0</emphasis> the next time that
Shorewall is started or restarted. Shorewall will create an ipset of type
<firstterm>iphash</firstterm>. If you want to use a different type of
ipset, such as <firstterm>macipmap</firstterm>, then you will want to
manually create that ipset yourself before the next Shorewall
start/restart.</para>
<para>The dynamic zone capability was added to Shorewall6 in Shorewall
4.4.21.</para>
</section>
<section>
<title>Adding a Host to a Dynamic Zone</title>
<para>Adding a host to a dynamic zone is accomplished by adding the host's
IP address to the appropriate ipset. Shorewall provldes a command for
doing that:</para>
<blockquote>
<para><command>shorewall add</command> <replaceable>interface:address
...</replaceable> <replaceable>zone</replaceable></para>
</blockquote>
<para>Example:</para>
<blockquote>
<para><command>shorewall add eth0:192.168.3.4 webok</command></para>
</blockquote>
<para>The command can only be used when the ipset involved is of type
iphash. For other ipset types, the <command>ipset</command> command must
be used directly.</para>
</section>
<section id="delete">
<title>Deleting a Host from a Dynamic Zone</title>
<para>Deleting a host from a dynamic zone is accomplished by removing the
host's IP address from the appropriate ipset. Shorewall provldes a command
for doing that:</para>
<blockquote>
<para><command>shorewall delete</command> <replaceable>interface:address
...</replaceable> <replaceable>zone</replaceable></para>
</blockquote>
<para>Example:</para>
<blockquote>
<para><command>shorewall delete eth0:192.168.3.4 webok</command></para>
</blockquote>
<para>The command can only be used when the ipset involved is of type
iphash. For other ipset types, the <command>ipset</command> command must
be used directly.</para>
</section>
<section id="listing">
<title>Listing the Contents of a Dynamic Zone</title>
<para>The shorewall show command may be used to list the current contents
of a dynamic zone.</para>
<blockquote>
<para><command>shorewall show dynamic</command>
<replaceable>zone</replaceable></para>
</blockquote>
<para>Example:</para>
<blockquote>
<programlisting><command>shorewall show dynamic webok</command>
eth0:
192.168.3.4
192.168.3.9</programlisting>
</blockquote>
</section>
<section id="start-stop">
<title>Dynamic Zone Contents and Shorewall stop/start/restart</title>
<para>The contents of a dynamic zone survive <command>shorewall
stop/shorewall start</command> and <command>shorewall restart</command>.
During <command>shorewall stop</command>, the contents of the ipsets are
saved in the file <filename>${VARDIR}/ipsets.save</filename> (usually
<filename>/var/lib/shorewall/ipsets.save</filename>). During
<command>shorewall start</command>, the contents of that file are restored
to the sets. During both <command>shorewall start</command> and
<command>shorewall restart</command>, any new ipsets required as a result
of a configuration change are added.</para>
</section>
<section id="restrictions">
<title>Restrictions</title>
<para>When using dynamic zones, you may not use ipsets in your <ulink
url="manpages/shorewall-routestopped.html">/etc/shorewall/routestopped</ulink>
file.</para>
</section>
</article>