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      <h1 align="center"><font color="#ffffff">Blacklisting Support</font></h1>
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<p>Shorewall supports two different forms of blacklisting; static and dynamic.</p>
   
<h2>Static Blacklisting</h2>
   
<p>Shorewall static blacklisting support has the following configuration parameters:</p>
   
<ul>
    <li>You specify whether you want packets from blacklisted hosts dropped 
or     rejected using the <a href="Documentation.htm#BLDisposition">BLACKLIST_DISPOSITION</a>
     setting in /etc/shorewall/shorewall.conf</li>
    <li>You specify whether you want packets from blacklisted hosts logged 
and at     what syslog level using the <a
 href="Documentation.htm#BLLoglevel">BLACKLIST_LOGLEVEL</a>     setting in 
/etc/shorewall/shorewall.conf</li>
    <li>You list the IP addresses/subnets that you wish to blacklist in <a
 href="Documentation.htm#Blacklist">/etc/shorewall/blacklist.</a> Beginning 
with Shorewall version 1.3.8, you may also specify PROTOCOL and Port numbers/Service 
names in the blacklist file.<br>
   </li>
    <li>You specify the interfaces whose incoming packets you want checked 
against     the blacklist using the "<a
 href="Documentation.htm#Interfaces">blacklist</a>"     option in /etc/shorewall/interfaces.</li>
    <li>The black list is refreshed from /etc/shorewall/blacklist by the
"<a href="Documentation.htm#Starting">shorewall     refresh</a>" command.</li>
   
</ul>
   
<h2>Dynamic Blacklisting</h2>
   
<p>Dynamic blacklisting support was added in version 1.3.2. Dynamic blacklisting 
 doesn't use any configuration parameters but is rather controlled using 
/sbin/shorewall commands:</p>
   
<ul>
    <li>drop <i>&lt;ip address list&gt; </i>- causes packets from the listed 
IP    addresses to be silently dropped by the firewall.</li>
    <li>reject <i>&lt;ip address list&gt; </i>- causes packets from the listed 
IP    addresses to be rejected by the firewall.</li>
    <li>allow <i>&lt;ip address list&gt; </i>- re-enables receipt of packets 
from hosts    previously blacklisted by a <i>deny</i> or <i>reject</i> command.</li>
    <li>save - save the dynamic blacklisting configuration so that it will 
be    automatically restored the next time that the firewall is restarted.</li>
    <li>show dynamic - displays the dynamic blacklisting configuration.</li>
   
</ul>
   
<p>Example 1:</p>
   
<pre>     shorewall drop 192.0.2.124 192.0.2.125</pre>
   
<p>��� Drops packets from hosts 192.0.2.124 and 192.0.2.125</p>
   
<p>Example 2:</p>
   
<pre>     shorewall allow 192.0.2.125</pre>
   
<p>��� Reenables access from 192.0.2.125.</p>
   
<p><font size="2">Last updated 10/7/2002 - <a href="support.htm">Tom Eastep</a></font></p>
    
<p><font face="Trebuchet MS"><a href="copyright.htm"><font size="2">Copyright</font> 
 � <font size="2">2002 Thomas M. Eastep.</font></a></font></p>
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