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diff --git a/contrib/bind9/doc/arm/Bv9ARM.ch07.html b/contrib/bind9/doc/arm/Bv9ARM.ch07.html index 86c2b6a..f4e26f06 100644 --- a/contrib/bind9/doc/arm/Bv9ARM.ch07.html +++ b/contrib/bind9/doc/arm/Bv9ARM.ch07.html @@ -1,5 +1,5 @@ <!-- - - Copyright (C) 2004, 2005 Internet Systems Consortium, Inc. ("ISC") + - Copyright (C) 2004-2006 Internet Systems Consortium, Inc. ("ISC") - Copyright (C) 2000-2003 Internet Software Consortium. - - Permission to use, copy, modify, and distribute this software for any @@ -14,12 +14,12 @@ - OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR - PERFORMANCE OF THIS SOFTWARE. --> -<!-- $Id: Bv9ARM.ch07.html,v 1.50.2.9.2.24 2005/10/13 02:34:02 marka Exp $ --> +<!-- $Id: Bv9ARM.ch07.html,v 1.50.2.9.2.33 2006/09/13 02:56:21 marka Exp $ --> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> <title>Chapter 7. BIND 9 Security Considerations</title> -<meta name="generator" content="DocBook XSL Stylesheets V1.69.1"> +<meta name="generator" content="DocBook XSL Stylesheets V1.70.1"> <link rel="start" href="Bv9ARM.html" title="BIND 9 Administrator Reference Manual"> <link rel="up" href="Bv9ARM.html" title="BIND 9 Administrator Reference Manual"> <link rel="prev" href="Bv9ARM.ch06.html" title="Chapter 6. BIND 9 Configuration Reference"> @@ -28,7 +28,7 @@ <body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> <div class="navheader"> <table width="100%" summary="Navigation header"> -<tr><th colspan="3" align="center">Chapter 7. <span class="acronym">BIND</span> 9 Security Considerations</th></tr> +<tr><th colspan="3" align="center">Chapter 7. <acronym class="acronym">BIND</acronym> 9 Security Considerations</th></tr> <tr> <td width="20%" align="left"> <a accesskey="p" href="Bv9ARM.ch06.html">Prev</a> </td> @@ -41,16 +41,16 @@ </div> <div class="chapter" lang="en"> <div class="titlepage"><div><div><h2 class="title"> -<a name="Bv9ARM.ch07"></a>Chapter 7. <span class="acronym">BIND</span> 9 Security Considerations</h2></div></div></div> +<a name="Bv9ARM.ch07"></a>Chapter 7. <acronym class="acronym">BIND</acronym> 9 Security Considerations</h2></div></div></div> <div class="toc"> <p><b>Table of Contents</b></p> <dl> <dt><span class="sect1"><a href="Bv9ARM.ch07.html#Access_Control_Lists">Access Control Lists</a></span></dt> -<dt><span class="sect1"><a href="Bv9ARM.ch07.html#id2567222"><span><strong class="command">chroot</strong></span> and <span><strong class="command">setuid</strong></span> (for +<dt><span class="sect1"><a href="Bv9ARM.ch07.html#id2591971"><span><strong class="command">chroot</strong></span> and <span><strong class="command">setuid</strong></span> (for UNIX servers)</a></span></dt> <dd><dl> -<dt><span class="sect2"><a href="Bv9ARM.ch07.html#id2567366">The <span><strong class="command">chroot</strong></span> Environment</a></span></dt> -<dt><span class="sect2"><a href="Bv9ARM.ch07.html#id2567424">Using the <span><strong class="command">setuid</strong></span> Function</a></span></dt> +<dt><span class="sect2"><a href="Bv9ARM.ch07.html#id2592046">The <span><strong class="command">chroot</strong></span> Environment</a></span></dt> +<dt><span class="sect2"><a href="Bv9ARM.ch07.html#id2592172">Using the <span><strong class="command">setuid</strong></span> Function</a></span></dt> </dl></dd> <dt><span class="sect1"><a href="Bv9ARM.ch07.html#dynamic_update_security">Dynamic Update Security</a></span></dt> </dl> @@ -68,13 +68,14 @@ your name server, without cluttering up your config files with huge lists of IP addresses.</p> <p>It is a <span class="emphasis"><em>good idea</em></span> to use ACLs, and to control access to your server. Limiting access to your server by -outside parties can help prevent spoofing and DoS attacks against -your server.</p> +outside parties can help prevent spoofing and denial of service (DoS) +attacks against your server.</p> <p>Here is an example of how to properly apply ACLs:</p> <pre class="programlisting"> // Set up an ACL named "bogusnets" that will block RFC1918 space, // which is commonly used in spoofing attacks. acl bogusnets { 0.0.0.0/8; 1.0.0.0/8; 2.0.0.0/8; 192.0.2.0/24; 224.0.0.0/3; 10.0.0.0/8; 172.16.0.0/12; 192.168.0.0/16; }; + // Set up an ACL called our-nets. Replace this with the real IP numbers. acl our-nets { x.x.x.x/24; x.x.x.x/21; }; options { @@ -86,6 +87,7 @@ options { blackhole { bogusnets; }; ... }; + zone "example.com" { type master; file "m/example.com"; @@ -100,28 +102,28 @@ see the <span class="emphasis"><em>AUSCERT</em></span> advisory at </div> <div class="sect1" lang="en"> <div class="titlepage"><div><div><h2 class="title" style="clear: both"> -<a name="id2567222"></a><span><strong class="command">chroot</strong></span> and <span><strong class="command">setuid</strong></span> (for +<a name="id2591971"></a><span><strong class="command">chroot</strong></span> and <span><strong class="command">setuid</strong></span> (for UNIX servers)</h2></div></div></div> -<p>On UNIX servers, it is possible to run <span class="acronym">BIND</span> in a <span class="emphasis"><em>chrooted</em></span> environment -(<span><strong class="command">chroot()</strong></span>) by specifying the "<code class="option">-t</code>" -option. This can help improve system security by placing <span class="acronym">BIND</span> in +<p>On UNIX servers, it is possible to run <acronym class="acronym">BIND</acronym> in a <span class="emphasis"><em>chrooted</em></span> environment +(using the <span><strong class="command">chroot()</strong></span> function) by specifying the "<code class="option">-t</code>" +option. This can help improve system security by placing <acronym class="acronym">BIND</acronym> in a "sandbox", which will limit the damage done if a server is compromised.</p> -<p>Another useful feature in the UNIX version of <span class="acronym">BIND</span> is the +<p>Another useful feature in the UNIX version of <acronym class="acronym">BIND</acronym> is the ability to run the daemon as an unprivileged user ( <code class="option">-u</code> <em class="replaceable"><code>user</code></em> ). We suggest running as an unprivileged user when using the <span><strong class="command">chroot</strong></span> feature.</p> -<p>Here is an example command line to load <span class="acronym">BIND</span> in a <span><strong class="command">chroot()</strong></span> sandbox, +<p>Here is an example command line to load <acronym class="acronym">BIND</acronym> in a <span><strong class="command">chroot</strong></span> sandbox, <span><strong class="command">/var/named</strong></span>, and to run <span><strong class="command">named</strong></span> <span><strong class="command">setuid</strong></span> to user 202:</p> <p><strong class="userinput"><code>/usr/local/bin/named -u 202 -t /var/named</code></strong></p> <div class="sect2" lang="en"> <div class="titlepage"><div><div><h3 class="title"> -<a name="id2567366"></a>The <span><strong class="command">chroot</strong></span> Environment</h3></div></div></div> -<p>In order for a <span><strong class="command">chroot()</strong></span> environment to +<a name="id2592046"></a>The <span><strong class="command">chroot</strong></span> Environment</h3></div></div></div> +<p>In order for a <span><strong class="command">chroot</strong></span> environment to work properly in a particular directory (for example, <code class="filename">/var/named</code>), you will need to set up an environment that includes everything -<span class="acronym">BIND</span> needs to run. -From <span class="acronym">BIND</span>'s point of view, <code class="filename">/var/named</code> is +<acronym class="acronym">BIND</acronym> needs to run. +From <acronym class="acronym">BIND</acronym>'s point of view, <code class="filename">/var/named</code> is the root of the filesystem. You will need to adjust the values of options like like <span><strong class="command">directory</strong></span> and <span><strong class="command">pid-file</strong></span> to account for this. @@ -134,18 +136,18 @@ However, depending on your operating system, you may need to set up things like <code class="filename">/dev/zero</code>, <code class="filename">/dev/random</code>, -<code class="filename">/dev/log</code>, and/or +<code class="filename">/dev/log</code>, and <code class="filename">/etc/localtime</code>. </p> </div> <div class="sect2" lang="en"> <div class="titlepage"><div><div><h3 class="title"> -<a name="id2567424"></a>Using the <span><strong class="command">setuid</strong></span> Function</h3></div></div></div> +<a name="id2592172"></a>Using the <span><strong class="command">setuid</strong></span> Function</h3></div></div></div> <p>Prior to running the <span><strong class="command">named</strong></span> daemon, use the <span><strong class="command">touch</strong></span> utility (to change file access and modification times) or the <span><strong class="command">chown</strong></span> utility (to set the user id and/or group id) on files -to which you want <span class="acronym">BIND</span> +to which you want <acronym class="acronym">BIND</acronym> to write. Note that if the <span><strong class="command">named</strong></span> daemon is running as an unprivileged user, it will not be able to bind to new restricted ports if the server is reloaded.</p> @@ -156,7 +158,7 @@ server is reloaded.</p> <a name="dynamic_update_security"></a>Dynamic Update Security</h2></div></div></div> <p>Access to the dynamic update facility should be strictly limited. In earlier versions of -<span class="acronym">BIND</span> the only way to do this was based on the IP +<acronym class="acronym">BIND</acronym>, the only way to do this was based on the IP address of the host requesting the update, by listing an IP address or network prefix in the <span><strong class="command">allow-update</strong></span> zone option. This method is insecure since the source address of the update UDP packet @@ -172,7 +174,7 @@ cryptographically authenticated by means of transaction signatures list only TSIG key names, not IP addresses or network prefixes. Alternatively, the new <span><strong class="command">update-policy</strong></span> option can be used.</p> -<p>Some sites choose to keep all dynamically updated DNS data +<p>Some sites choose to keep all dynamically-updated DNS data in a subdomain and delegate that subdomain to a separate zone. This way, the top-level zone containing critical data such as the IP addresses of public web and mail servers need not allow dynamic update at @@ -190,7 +192,7 @@ all.</p> </td> </tr> <tr> -<td width="40%" align="left" valign="top">Chapter 6. <span class="acronym">BIND</span> 9 Configuration Reference </td> +<td width="40%" align="left" valign="top">Chapter 6. <acronym class="acronym">BIND</acronym> 9 Configuration Reference </td> <td width="20%" align="center"><a accesskey="h" href="Bv9ARM.html">Home</a></td> <td width="40%" align="right" valign="top"> Chapter 8. Troubleshooting</td> </tr> |