mirror of
https://gitlab.com/shorewall/code.git
synced 2024-12-15 10:51:02 +01:00
c2ccd7fd3d
git-svn-id: https://shorewall.svn.sourceforge.net/svnroot/shorewall/trunk@800 fbd18981-670d-0410-9b5c-8dc0c1a9a2bb
92 lines
3.8 KiB
HTML
92 lines
3.8 KiB
HTML
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
|
||
<html>
|
||
<head>
|
||
<meta http-equiv="Content-Language" content="en-us">
|
||
<meta http-equiv="Content-Type"
|
||
content="text/html; charset=windows-1252">
|
||
<meta name="GENERATOR" content="Microsoft FrontPage 5.0">
|
||
<meta name="ProgId" content="FrontPage.Editor.Document">
|
||
<title>Blacklisting Support</title>
|
||
</head>
|
||
<body>
|
||
<h1 style="text-align: center;">Shorewall Blacklisting Support<br>
|
||
</h1>
|
||
<p>Shorewall supports two different forms of blacklisting; static and
|
||
dynamic. Beginning with Shorewall version 1.4.8, the BLACKLISTNEWONLY
|
||
option in /etc/shorewall/shorewall.conf controls the degree of
|
||
blacklist filtering:<br>
|
||
</p>
|
||
<ol>
|
||
<li>BLACKLISTNEWONLY=No -- All incoming packets are checked
|
||
against the blacklist. New blacklist entries can be used to terminate
|
||
existing connections. Versions of Shorewall prior to 1.4.8 behave in
|
||
this manner.<br>
|
||
</li>
|
||
<li>BLACKLISTNEWONLY=Yes -- The blacklists are only consulted for new
|
||
connection requests. Blacklists may not be used to terminate existing
|
||
connections.</li>
|
||
</ol>
|
||
Only the source address is checked against the blacklists.<br>
|
||
<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><ip address list> </i>- causes packets from the
|
||
listed IP addresses to be silently dropped by the firewall.</li>
|
||
<li>reject <i><ip address list> </i>- causes packets from the
|
||
listed IP addresses to be rejected by the firewall.</li>
|
||
<li>allow <i><ip address list> </i>- re-enables receipt of
|
||
packets from hosts previously blacklisted by a <i>drop</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>
|
||
Dynamic blacklisting is <u>not</u> dependent on the "blacklist" option
|
||
in /etc/shorewall/interfaces.<br>
|
||
<p>Example 1:</p>
|
||
<pre> <b><font color="#009900">shorewall drop 192.0.2.124 192.0.2.125</font></b></pre>
|
||
<p> Drops packets from hosts 192.0.2.124 and
|
||
192.0.2.125</p>
|
||
<p>Example 2:</p>
|
||
<pre> <b><font color="#009900">shorewall allow 192.0.2.125</font></b></pre>
|
||
<p> Reenables access from 192.0.2.125.</p>
|
||
<p><font size="2">Last updated 11/14/2003 - <a href="support.htm">Tom
|
||
Eastep</a></font></p>
|
||
<p><font face="Trebuchet MS"><a href="copyright.htm"><font size="2">Copyright</font>
|
||
<EFBFBD> <font size="2">2002, 2003 Thomas M. Eastep.</font></a></font></p>
|
||
<br>
|
||
<br>
|
||
<br>
|
||
<br>
|
||
<br>
|
||
</body>
|
||
</html>
|