Bv9ARM.ch04.html revision ebabe300b615154d08f5577822cfd8726d2643c8
3b4098640dd85040270f39b9a5ee5e22de99d3d6Mark Andrews - Copyright (C) 2004-2010 Internet Systems Consortium, Inc. ("ISC")
75c0816e8295e180f4bc7f10db3d0d880383bc1cMark Andrews - Copyright (C) 2000-2003 Internet Software Consortium.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein - Permission to use, copy, modify, and/or distribute this software for any
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein - purpose with or without fee is hereby granted, provided that the above
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein - copyright notice and this permission notice appear in all copies.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein - THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein - REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein - AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein - INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein - LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein - OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein - PERFORMANCE OF THIS SOFTWARE.
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews<!-- $Id: Bv9ARM.ch04.html,v 1.121 2011/01/04 01:14:08 tbox Exp $ -->
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
cedb0bd0c1e3c461b7e479a16d3adfd5b150f1f4Mark Andrews<meta name="generator" content="DocBook XSL Stylesheets V1.71.1">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<link rel="start" href="Bv9ARM.html" title="BIND 9 Administrator Reference Manual">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<link rel="up" href="Bv9ARM.html" title="BIND 9 Administrator Reference Manual">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<link rel="prev" href="Bv9ARM.ch03.html" title="Chapter�3.�Name Server Configuration">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<link rel="next" href="Bv9ARM.ch05.html" title="Chapter�5.�The BIND 9 Lightweight Resolver">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<tr><th colspan="3" align="center">Chapter�4.�Advanced DNS Features</th></tr>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a accesskey="p" href="Bv9ARM.ch03.html">Prev</a>�</td>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<td width="20%" align="right">�<a accesskey="n" href="Bv9ARM.ch05.html">Next</a>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h2 class="title">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="Bv9ARM.ch04"></a>Chapter�4.�Advanced DNS Features</h2></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect1"><a href="Bv9ARM.ch04.html#notify">Notify</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect1"><a href="Bv9ARM.ch04.html#dynamic_update">Dynamic Update</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dd><dl><dt><span class="sect2"><a href="Bv9ARM.ch04.html#journal">The journal file</a></span></dt></dl></dd>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect1"><a href="Bv9ARM.ch04.html#incremental_zone_transfers">Incremental Zone Transfers (IXFR)</a></span></dt>
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews<dt><span class="sect1"><a href="Bv9ARM.ch04.html#id2570820">Split DNS</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dd><dl><dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2570838">Example split DNS setup</a></span></dt></dl></dd>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect1"><a href="Bv9ARM.ch04.html#tsig">TSIG</a></span></dt>
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571339">Generate Shared Keys for Each Pair of Hosts</a></span></dt>
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571549">Copying the Shared Secret to Both Machines</a></span></dt>
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571560">Informing the Servers of the Key's Existence</a></span></dt>
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571596">Instructing the Server to Use the Key</a></span></dt>
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571654">TSIG Key Based Access Control</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571703">Errors</a></span></dt>
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews<dt><span class="sect1"><a href="Bv9ARM.ch04.html#id2571717">TKEY</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect1"><a href="Bv9ARM.ch04.html#id2563984">SIG(0)</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect1"><a href="Bv9ARM.ch04.html#DNSSEC">DNSSEC</a></span></dt>
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2564120">Generating Keys</a></span></dt>
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2572186">Signing the Zone</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2572267">Configuring Servers</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect1"><a href="Bv9ARM.ch04.html#dnssec.dynamic.zones">DNSSEC, Dynamic Zones, and Automatic Signing</a></span></dt>
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2606953">Converting from insecure to secure</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2563505">Dynamic DNS update method</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2563541">Fully automatic zone signing</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2563691">Private-type records</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2563729">DNSKEY rollovers</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2563741">Dynamic DNS update method</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2563843">Automatic key rollovers</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2563869">NSEC3PARAM rollovers via UPDATE</a></span></dt>
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2563879">Converting from NSEC to NSEC3</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2563889">Converting from NSEC3 to NSEC</a></span></dt>
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571820">Converting from secure to insecure</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571858">Periodic re-signing</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571867">NSEC3 and OPTOUT</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect1"><a href="Bv9ARM.ch04.html#rfc5011.support">Dynamic Trust Anchor Management</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571921">Validating Resolver</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571943">Authoritative Server</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect1"><a href="Bv9ARM.ch04.html#pkcs11">PKCS #11 (Cryptoki) support</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2609194">Prerequisites</a></span></dt>
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2607349">Building BIND 9 with PKCS#11</a></span></dt>
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2607444">PKCS #11 Tools</a></span></dt>
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2607543">Using the HSM</a></span></dt>
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2609585">Specifying the engine on the command line</a></span></dt>
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2634002">Running named with automatic zone re-signing</a></span></dt>
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews<dt><span class="sect1"><a href="Bv9ARM.ch04.html#id2572487">IPv6 Support in <acronym class="acronym">BIND</acronym> 9</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2572754">Address Lookups Using AAAA Records</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2572843">Address to Name Lookups Using Nibble Format</a></span></dt>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h2 class="title" style="clear: both">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="notify"></a>Notify</h2></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <acronym class="acronym">DNS</acronym> NOTIFY is a mechanism that allows master
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein servers to notify their slave servers of changes to a zone's data. In
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein response to a <span><strong class="command">NOTIFY</strong></span> from a master server, the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein slave will check to see that its version of the zone is the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein current version and, if not, initiate a zone transfer.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein For more information about <acronym class="acronym">DNS</acronym>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">NOTIFY</strong></span>, see the description of the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">notify</strong></span> option in <a href="Bv9ARM.ch06.html#boolean_options" title="Boolean Options">the section called “Boolean Options”</a> and
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein the description of the zone option <span><strong class="command">also-notify</strong></span> in
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <a href="Bv9ARM.ch06.html#zone_transfers" title="Zone Transfers">the section called “Zone Transfers”</a>. The <span><strong class="command">NOTIFY</strong></span>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein protocol is specified in RFC 1996.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein As a slave zone can also be a master to other slaves, <span><strong class="command">named</strong></span>,
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein by default, sends <span><strong class="command">NOTIFY</strong></span> messages for every zone
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein it loads. Specifying <span><strong class="command">notify master-only;</strong></span> will
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein cause <span><strong class="command">named</strong></span> to only send <span><strong class="command">NOTIFY</strong></span> for master
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein zones that it loads.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h2 class="title" style="clear: both">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="dynamic_update"></a>Dynamic Update</h2></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Dynamic Update is a method for adding, replacing or deleting
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein records in a master server by sending it a special form of DNS
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein messages. The format and meaning of these messages is specified
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein in RFC 2136.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Dynamic update is enabled by including an
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">allow-update</strong></span> or an <span><strong class="command">update-policy</strong></span>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein clause in the <span><strong class="command">zone</strong></span> statement.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein If the zone's <span><strong class="command">update-policy</strong></span> is set to
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <strong class="userinput"><code>local</code></strong>, updates to the zone
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein will be permitted for the key <code class="varname">local-ddns</code>,
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein which will be generated by <span><strong class="command">named</strong></span> at startup.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein See <a href="Bv9ARM.ch06.html#dynamic_update_policies" title="Dynamic Update Policies">the section called “Dynamic Update Policies”</a> for more details.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Dynamic updates using Kerberos signed requests can be made
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein using the TKEY/GSS protocol by setting either the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">tkey-gssapi-keytab</strong></span> option, or alternatively
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein by setting both the <span><strong class="command">tkey-gssapi-credential</strong></span>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein and <span><strong class="command">tkey-domain</strong></span> options. Once enabled,
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Kerberos signed requests will be matched against the update
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein policies for the zone, using the Kerberos principal as the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein signer for the request.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Updating of secure zones (zones using DNSSEC) follows RFC
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 3007: RRSIG, NSEC and NSEC3 records affected by updates are
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein automatically regenerated by the server using an online
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein zone key. Update authorization is based on transaction
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein signatures and an explicit server policy.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h3 class="title">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="journal"></a>The journal file</h3></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein All changes made to a zone using dynamic update are stored
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein in the zone's journal file. This file is automatically created
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein by the server when the first dynamic update takes place.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The name of the journal file is formed by appending the extension
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <code class="filename">.jnl</code> to the name of the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein corresponding zone
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein file unless specifically overridden. The journal file is in a
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein binary format and should not be edited manually.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The server will also occasionally write ("dump")
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein the complete contents of the updated zone to its zone file.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein This is not done immediately after
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein each dynamic update, because that would be too slow when a large
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein zone is updated frequently. Instead, the dump is delayed by
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein up to 15 minutes, allowing additional updates to take place.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein During the dump process, transient files will be created
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein with the extensions <code class="filename">.jnw</code> and
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <code class="filename">.jbk</code>; under ordinary circumstances, these
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein will be removed when the dump is complete, and can be safely
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein When a server is restarted after a shutdown or crash, it will replay
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein the journal file to incorporate into the zone any updates that
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein place after the last zone dump.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Changes that result from incoming incremental zone transfers are
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein journalled in a similar way.
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews The zone files of dynamic zones cannot normally be edited by
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews hand because they are not guaranteed to contain the most recent
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein dynamic changes — those are only in the journal file.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The only way to ensure that the zone file of a dynamic zone
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein is up to date is to run <span><strong class="command">rndc stop</strong></span>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein If you have to make changes to a dynamic zone
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein manually, the following procedure will work: Disable dynamic updates
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to the zone using
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">rndc freeze <em class="replaceable"><code>zone</code></em></strong></span>.
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews This will also remove the zone's <code class="filename">.jnl</code> file
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews and update the master file. Edit the zone file. Run
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews <span><strong class="command">rndc thaw <em class="replaceable"><code>zone</code></em></strong></span>
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews to reload the changed zone and re-enable dynamic updates.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h2 class="title" style="clear: both">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="incremental_zone_transfers"></a>Incremental Zone Transfers (IXFR)</h2></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The incremental zone transfer (IXFR) protocol is a way for
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein slave servers to transfer only changed data, instead of having to
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein transfer the entire zone. The IXFR protocol is specified in RFC
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 1995. See <a href="Bv9ARM.ch09.html#proposed_standards">Proposed Standards</a>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein When acting as a master, <acronym class="acronym">BIND</acronym> 9
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein supports IXFR for those zones
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein where the necessary change history information is available. These
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein include master zones maintained by dynamic update and slave zones
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein whose data was obtained by IXFR. For manually maintained master
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein zones, and for slave zones obtained by performing a full zone
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein transfer (AXFR), IXFR is supported only if the option
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">ixfr-from-differences</strong></span> is set
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to <strong class="userinput"><code>yes</code></strong>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein When acting as a slave, <acronym class="acronym">BIND</acronym> 9 will
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein attempt to use IXFR unless
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein it is explicitly disabled. For more information about disabling
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein IXFR, see the description of the <span><strong class="command">request-ixfr</strong></span> clause
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein of the <span><strong class="command">server</strong></span> statement.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h2 class="title" style="clear: both">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="id2570820"></a>Split DNS</h2></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Setting up different views, or visibility, of the DNS space to
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein internal and external resolvers is usually referred to as a
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span class="emphasis"><em>Split DNS</em></span> setup. There are several
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein reasons an organization would want to set up its DNS this way.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein One common reason for setting up a DNS system this way is
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to hide "internal" DNS information from "external" clients on the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Internet. There is some debate as to whether or not this is actually
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Internal DNS information leaks out in many ways (via email headers,
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein for example) and most savvy "attackers" can find the information
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein they need using other means.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein However, since listing addresses of internal servers that
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein external clients cannot possibly reach can result in
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein connection delays and other annoyances, an organization may
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein choose to use a Split DNS to present a consistent view of itself
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to the outside world.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Another common reason for setting up a Split DNS system is
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to allow internal networks that are behind filters or in RFC 1918
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein space (reserved IP space, as documented in RFC 1918) to resolve DNS
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein on the Internet. Split DNS can also be used to allow mail from outside
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein back in to the internal network.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h3 class="title">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="id2570838"></a>Example split DNS setup</h3></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Let's say a company named <span class="emphasis"><em>Example, Inc.</em></span>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein has several corporate sites that have an internal network with
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Internet Protocol (IP) space and an external demilitarized zone (DMZ),
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein or "outside" section of a network, that is available to the public.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span class="emphasis"><em>Example, Inc.</em></span> wants its internal clients
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to be able to resolve external hostnames and to exchange mail with
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein people on the outside. The company also wants its internal resolvers
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to have access to certain internal-only zones that are not available
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein at all outside of the internal network.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein In order to accomplish this, the company will set up two sets
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein of name servers. One set will be on the inside network (in the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein IP space) and the other set will be on bastion hosts, which are
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein hosts that can talk to both sides of its network, in the DMZ.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The internal servers will be configured to forward all queries,
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein except queries for <code class="filename">site1.internal</code>, <code class="filename">site2.internal</code>, <code class="filename">site1.example.com</code>,
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein and <code class="filename">site2.example.com</code>, to the servers
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein DMZ. These internal servers will have complete sets of information
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein for <code class="filename">site1.example.com</code>, <code class="filename">site2.example.com</code>, <code class="filename">site1.internal</code>,
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein and <code class="filename">site2.internal</code>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein To protect the <code class="filename">site1.internal</code> and <code class="filename">site2.internal</code> domains,
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein the internal name servers must be configured to disallow all queries
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to these domains from any external hosts, including the bastion
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The external servers, which are on the bastion hosts, will
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein be configured to serve the "public" version of the <code class="filename">site1</code> and <code class="filename">site2.example.com</code> zones.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein This could include things such as the host records for public servers
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein (<code class="filename">www.example.com</code> and <code class="filename">ftp.example.com</code>),
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein and mail exchange (MX) records (<code class="filename">a.mx.example.com</code> and <code class="filename">b.mx.example.com</code>).
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein In addition, the public <code class="filename">site1</code> and <code class="filename">site2.example.com</code> zones
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein should have special MX records that contain wildcard (`*') records
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein pointing to the bastion hosts. This is needed because external mail
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein servers do not have any other way of looking up how to deliver mail
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to those internal hosts. With the wildcard records, the mail will
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein be delivered to the bastion host, which can then forward it on to
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein internal hosts.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Here's an example of a wildcard MX record:
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<pre class="programlisting">* IN MX 10 external1.example.com.</pre>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Now that they accept mail on behalf of anything in the internal
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews network, the bastion hosts will need to know how to deliver mail
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to internal hosts. In order for this to work properly, the resolvers
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein the bastion hosts will need to be configured to point to the internal
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein name servers for DNS resolution.
c71787bd6356c92e9c7d0a174cd63ab17fcf34c6Eric Luce Queries for internal hostnames will be answered by the internal
c71787bd6356c92e9c7d0a174cd63ab17fcf34c6Eric Luce servers, and queries for external hostnames will be forwarded back
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein out to the DNS servers on the bastion hosts.
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce In order for all this to work properly, internal clients will
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce need to be configured to query <span class="emphasis"><em>only</em></span> the internal
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce name servers for DNS queries. This could also be enforced via
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews filtering on the network.
8e245ec21beee31a780de9b89ba1e8bb2b9f4c9aAndreas Gustafsson If everything has been set properly, <span class="emphasis"><em>Example, Inc.</em></span>'s
8e245ec21beee31a780de9b89ba1e8bb2b9f4c9aAndreas Gustafsson internal clients will now be able to:
c71787bd6356c92e9c7d0a174cd63ab17fcf34c6Eric Luce Look up any hostnames in the <code class="literal">site1</code>
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce <code class="literal">site2.example.com</code> zones.
8e245ec21beee31a780de9b89ba1e8bb2b9f4c9aAndreas Gustafsson Look up any hostnames in the <code class="literal">site1.internal</code> and
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce <code class="literal">site2.internal</code> domains.
c71787bd6356c92e9c7d0a174cd63ab17fcf34c6Eric Luce<li>Exchange mail with both internal and external people.</li>
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce Hosts on the Internet will be able to:
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce Look up any hostnames in the <code class="literal">site1</code>
c71787bd6356c92e9c7d0a174cd63ab17fcf34c6Eric Luce <code class="literal">site2.example.com</code> zones.
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce Exchange mail with anyone in the <code class="literal">site1</code> and
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce <code class="literal">site2.example.com</code> zones.
c71787bd6356c92e9c7d0a174cd63ab17fcf34c6Eric Luce Here is an example configuration for the setup we just
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce described above. Note that this is only configuration information;
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce for information on how to configure your zone files, see <a href="Bv9ARM.ch03.html#sample_configuration" title="Sample Configurations">the section called “Sample Configurations”</a>.
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce Internal DNS server config:
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austeinacl internals { 172.16.72.0/24; 192.168.1.0/24; };
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austeinacl externals { <code class="varname">bastion-ips-go-here</code>; };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce forward only;
c71787bd6356c92e9c7d0a174cd63ab17fcf34c6Eric Luce // forward to external servers
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce forwarders {
8e245ec21beee31a780de9b89ba1e8bb2b9f4c9aAndreas Gustafsson // sample allow-transfer (no one)
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews allow-transfer { none; };
575e532437cf7f203707765e21767db92fa1e480Mark Andrews // restrict query access
8e245ec21beee31a780de9b89ba1e8bb2b9f4c9aAndreas Gustafsson allow-query { internals; externals; };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce // restrict recursion
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce allow-recursion { internals; };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce// sample master zone
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce type master;
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce // do normal iterative resolution (do not forward)
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce forwarders { };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce allow-query { internals; externals; };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce allow-transfer { internals; };
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein// sample slave zone
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein masters { 172.16.72.3; };
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein forwarders { };
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein allow-query { internals; externals; };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce allow-transfer { internals; };
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein type master;
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein forwarders { };
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein allow-query { internals; };
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein allow-transfer { internals; }
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein masters { 172.16.72.3; };
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein forwarders { };
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein allow-query { internals };
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein allow-transfer { internals; }
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein External (bastion host) DNS server config:
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrewsacl internals { 172.16.72.0/24; 192.168.1.0/24; };
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austeinacl externals { bastion-ips-go-here; };
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein // sample allow-transfer (no one)
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein allow-transfer { none; };
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein // default query access
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews allow-query { any; };
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein // restrict cache access
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein allow-query-cache { internals; externals; };
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein // restrict recursion
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein allow-recursion { internals; externals; };
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein// sample slave zone
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein type master;
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein allow-transfer { internals; externals; };
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein masters { another_bastion_host_maybe; };
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein allow-transfer { internals; externals; }
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein In the <code class="filename">resolv.conf</code> (or equivalent) on
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein the bastion host(s):
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austeinnameserver 172.16.72.2
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austeinnameserver 172.16.72.3
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austeinnameserver 172.16.72.4
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h2 class="title" style="clear: both">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein This is a short guide to setting up Transaction SIGnatures
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein (TSIG) based transaction security in <acronym class="acronym">BIND</acronym>. It describes changes
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to the configuration file as well as what changes are required for
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein different features, including the process of creating transaction
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein keys and using transaction signatures with <acronym class="acronym">BIND</acronym>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <acronym class="acronym">BIND</acronym> primarily supports TSIG for server
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to server communication.
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews This includes zone transfer, notify, and recursive query messages.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Resolvers based on newer versions of <acronym class="acronym">BIND</acronym> 8 have limited support
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein TSIG can also be useful for dynamic update. A primary
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein server for a dynamic zone should control access to the dynamic
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein update service, but IP-based access control is insufficient.
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews The cryptographic access control provided by TSIG
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein is far superior. The <span><strong class="command">nsupdate</strong></span>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein program supports TSIG via the <code class="option">-k</code> and
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <code class="option">-y</code> command line options or inline by use
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein of the <span><strong class="command">key</strong></span>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h3 class="title">
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce<a name="id2571339"></a>Generate Shared Keys for Each Pair of Hosts</h3></div></div></div>
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce A shared secret is generated to be shared between <span class="emphasis"><em>host1</em></span> and <span class="emphasis"><em>host2</em></span>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein An arbitrary key name is chosen: "host1-host2.". The key name must
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein be the same on both hosts.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h4 class="title">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="id2571356"></a>Automatic Generation</h4></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The following command will generate a 128-bit (16 byte) HMAC-SHA256
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein key as described above. Longer keys are better, but shorter keys
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein are easier to read. Note that the maximum key length is the digest
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein length, here 256 bits.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <strong class="userinput"><code>dnssec-keygen -a hmac-sha256 -b 128 -n HOST host1-host2.</code></strong>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The key is in the file <code class="filename">Khost1-host2.+163+00000.private</code>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Nothing directly uses this file, but the base-64 encoded string
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein can be extracted from the file and used as a shared secret:
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<pre class="programlisting">Key: La/E5CjG9O+os1jq0a2jdA==</pre>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The string "<code class="literal">La/E5CjG9O+os1jq0a2jdA==</code>" can
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein be used as the shared secret.
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce<div class="titlepage"><div><div><h4 class="title">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="id2571395"></a>Manual Generation</h4></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The shared secret is simply a random sequence of bits, encoded
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein in base-64. Most ASCII strings are valid base-64 strings (assuming
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein the length is a multiple of 4 and only valid characters are used),
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein so the shared secret can be manually generated.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Also, a known string can be run through <span><strong class="command">mmencode</strong></span> or
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein a similar program to generate base-64 encoded data.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h3 class="title">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="id2571549"></a>Copying the Shared Secret to Both Machines</h3></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein This is beyond the scope of DNS. A secure transport mechanism
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein should be used. This could be secure FTP, ssh, telephone, etc.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h3 class="title">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="id2571560"></a>Informing the Servers of the Key's Existence</h3></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Imagine <span class="emphasis"><em>host1</em></span> and <span class="emphasis"><em>host 2</em></span>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein both servers. The following is added to each server's <code class="filename">named.conf</code> file:
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austeinkey host1-host2. {
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein algorithm hmac-sha256;
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The secret is the one generated above. Since this is a secret, it
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein is recommended that either <code class="filename">named.conf</code> be
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein non-world readable, or the key directive be added to a non-world
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein readable file that is included by <code class="filename">named.conf</code>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein At this point, the key is recognized. This means that if the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein server receives a message signed by this key, it can verify the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein signature. If the signature is successfully verified, the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein response is signed by the same key.
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews<div class="titlepage"><div><div><h3 class="title">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="id2571596"></a>Instructing the Server to Use the Key</h3></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Since keys are shared between two hosts only, the server must
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews be told when keys are to be used. The following is added to the <code class="filename">named.conf</code> file
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein for <span class="emphasis"><em>host1</em></span>, if the IP address of <span class="emphasis"><em>host2</em></span> is
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austeinserver 10.1.2.3 {
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein keys { host1-host2. ;};
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Multiple keys may be present, but only the first is used.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein This directive does not contain any secrets, so it may be in a
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein world-readable
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews If <span class="emphasis"><em>host1</em></span> sends a message that is a request
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to that address, the message will be signed with the specified key. <span class="emphasis"><em>host1</em></span> will
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein expect any responses to signed messages to be signed with the same
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews A similar statement must be present in <span class="emphasis"><em>host2</em></span>'s
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein configuration file (with <span class="emphasis"><em>host1</em></span>'s address) for <span class="emphasis"><em>host2</em></span> to
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein sign request messages to <span class="emphasis"><em>host1</em></span>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h3 class="title">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="id2571654"></a>TSIG Key Based Access Control</h3></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <acronym class="acronym">BIND</acronym> allows IP addresses and ranges
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to be specified in ACL
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein definitions and
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">allow-{ query | transfer | update }</strong></span>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein This has been extended to allow TSIG keys also. The above key would
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein be denoted <span><strong class="command">key host1-host2.</strong></span>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein An example of an <span><strong class="command">allow-update</strong></span> directive would be:
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austeinallow-update { key host1-host2. ;};
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein This allows dynamic updates to succeed only if the request
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein was signed by a key named "<span><strong class="command">host1-host2.</strong></span>".
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein See <a href="Bv9ARM.ch06.html#dynamic_update_policies" title="Dynamic Update Policies">the section called “Dynamic Update Policies”</a> for a discussion of
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein the more flexible <span><strong class="command">update-policy</strong></span> statement.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h3 class="title">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="id2571703"></a>Errors</h3></div></div></div>
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews The processing of TSIG signed messages can result in
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein several errors. If a signed message is sent to a non-TSIG aware
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein server, a FORMERR (format error) will be returned, since the server will not
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein understand the record. This is a result of misconfiguration,
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein since the server must be explicitly configured to send a TSIG
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein signed message to a specific server.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein If a TSIG aware server receives a message signed by an
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein unknown key, the response will be unsigned with the TSIG
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein extended error code set to BADKEY. If a TSIG aware server
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein receives a message with a signature that does not validate, the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein response will be unsigned with the TSIG extended error code set
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to BADSIG. If a TSIG aware server receives a message with a time
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein outside of the allowed range, the response will be signed with
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein the TSIG extended error code set to BADTIME, and the time values
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein will be adjusted so that the response can be successfully
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein verified. In any of these cases, the message's rcode (response code) is set to
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein NOTAUTH (not authenticated).
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h2 class="title" style="clear: both">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="id2571717"></a>TKEY</h2></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<p><span><strong class="command">TKEY</strong></span>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein is a mechanism for automatically generating a shared secret
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein between two hosts. There are several "modes" of
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">TKEY</strong></span> that specify how the key is generated
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews or assigned. <acronym class="acronym">BIND</acronym> 9 implements only one of
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews these modes, the Diffie-Hellman key exchange. Both hosts are
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein required to have a Diffie-Hellman KEY record (although this
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein record is not required to be present in a zone). The
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">TKEY</strong></span> process must use signed messages,
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein signed either by TSIG or SIG(0). The result of
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">TKEY</strong></span> is a shared secret that can be used to
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein sign messages with TSIG. <span><strong class="command">TKEY</strong></span> can also be
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein used to delete shared secrets that it had previously
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews The <span><strong class="command">TKEY</strong></span> process is initiated by a
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein or server by sending a signed <span><strong class="command">TKEY</strong></span>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein (including any appropriate KEYs) to a TKEY-aware server. The
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein server response, if it indicates success, will contain a
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">TKEY</strong></span> record and any appropriate keys.
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews this exchange, both participants have enough information to
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein determine the shared secret; the exact process depends on the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">TKEY</strong></span> mode. When using the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Diffie-Hellman
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">TKEY</strong></span> mode, Diffie-Hellman keys are
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein and the shared secret is derived by both participants.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h2 class="title" style="clear: both">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="id2563984"></a>SIG(0)</h2></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <acronym class="acronym">BIND</acronym> 9 partially supports DNSSEC SIG(0)
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein transaction signatures as specified in RFC 2535 and RFC 2931.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein uses public/private keys to authenticate messages. Access control
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein is performed in the same manner as TSIG keys; privileges can be
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein granted or denied based on the key name.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein When a SIG(0) signed message is received, it will only be
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein verified if the key is known and trusted by the server; the server
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein will not attempt to locate and/or validate the key.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein SIG(0) signing of multiple-message TCP streams is not
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The only tool shipped with <acronym class="acronym">BIND</acronym> 9 that
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein generates SIG(0) signed messages is <span><strong class="command">nsupdate</strong></span>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h2 class="title" style="clear: both">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="DNSSEC"></a>DNSSEC</h2></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Cryptographic authentication of DNS information is possible
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein through the DNS Security (<span class="emphasis"><em>DNSSEC-bis</em></span>) extensions,
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein defined in RFC 4033, RFC 4034, and RFC 4035.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein This section describes the creation and use of DNSSEC signed zones.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein In order to set up a DNSSEC secure zone, there are a series
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein of steps which must be followed. <acronym class="acronym">BIND</acronym>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein with several tools
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein that are used in this process, which are explained in more detail
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein below. In all cases, the <code class="option">-h</code> option prints a
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein full list of parameters. Note that the DNSSEC tools require the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein keyset files to be in the working directory or the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein directory specified by the <code class="option">-d</code> option, and
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein that the tools shipped with BIND 9.2.x and earlier are not compatible
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein with the current ones.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein There must also be communication with the administrators of
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein the parent and/or child zone to transmit keys. A zone's security
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein status must be indicated by the parent zone for a DNSSEC capable
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein resolver to trust its data. This is done through the presence
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein or absence of a <code class="literal">DS</code> record at the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein For other servers to trust data in this zone, they must
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein either be statically configured with this zone's zone key or the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein zone key of another zone above this one in the DNS tree.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h3 class="title">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a name="id2564120"></a>Generating Keys</h3></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The <span><strong class="command">dnssec-keygen</strong></span> program is used to
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein generate keys.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein A secure zone must contain one or more zone keys. The
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein zone keys will sign all other records in the zone, as well as
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein the zone keys of any secure delegated zones. Zone keys must
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein have the same name as the zone, a name type of
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">ZONE</strong></span>, and must be usable for
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein authentication.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein It is recommended that zone keys use a cryptographic algorithm
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein designated as "mandatory to implement" by the IETF; currently
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein the only one is RSASHA1.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The following command will generate a 768-bit RSASHA1 key for
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein the <code class="filename">child.example</code> zone:
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <strong class="userinput"><code>dnssec-keygen -a RSASHA1 -b 768 -n ZONE child.example.</code></strong>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Two output files will be produced:
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <code class="filename">Kchild.example.+005+12345.key</code> and
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews <code class="filename">Kchild.example.+005+12345.private</code>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 12345 is an example of a key tag). The key filenames contain
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein the key name (<code class="filename">child.example.</code>),
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein algorithm (3
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein is DSA, 1 is RSAMD5, 5 is RSASHA1, etc.), and the key tag (12345 in
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The private key (in the <code class="filename">.private</code>
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews used to generate signatures, and the public key (in the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <code class="filename">.key</code> file) is used for signature
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews verification.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein To generate another key with the same properties (but with
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein a different key tag), repeat the above command.
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews The <span><strong class="command">dnssec-keyfromlabel</strong></span> program is used
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews to get a key pair from a crypto hardware and build the key
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews files. Its usage is similar to <span><strong class="command">dnssec-keygen</strong></span>.
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews The public keys should be inserted into the zone file by
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews including the <code class="filename">.key</code> files using
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews <span><strong class="command">$INCLUDE</strong></span> statements.
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews<div class="titlepage"><div><div><h3 class="title">
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews<a name="id2572186"></a>Signing the Zone</h3></div></div></div>
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews The <span><strong class="command">dnssec-signzone</strong></span> program is used
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews to sign a zone.
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews Any <code class="filename">keyset</code> files corresponding to
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews secure subzones should be present. The zone signer will
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews generate <code class="literal">NSEC</code>, <code class="literal">NSEC3</code>
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews and <code class="literal">RRSIG</code> records for the zone, as
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews well as <code class="literal">DS</code> for the child zones if
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews <code class="literal">'-g'</code> is specified. If <code class="literal">'-g'</code>
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews is not specified, then DS RRsets for the secure child
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews zones need to be added manually.
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews The following command signs the zone, assuming it is in a
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews file called <code class="filename">zone.child.example</code>. By
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews default, all zone keys which have an available private key are
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews used to generate signatures.
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews <strong class="userinput"><code>dnssec-signzone -o child.example zone.child.example</code></strong>
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews One output file is produced:
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews <code class="filename">zone.child.example.signed</code>. This
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews should be referenced by <code class="filename">named.conf</code>
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews input file for the zone.
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews<p><span><strong class="command">dnssec-signzone</strong></span>
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews will also produce a keyset and dsset files and optionally a
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews dlvset file. These are used to provide the parent zone
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews administrators with the <code class="literal">DNSKEYs</code> (or their
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews corresponding <code class="literal">DS</code> records) that are the
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews secure entry point to the zone.
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews<div class="titlepage"><div><div><h3 class="title">
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews<a name="id2572267"></a>Configuring Servers</h3></div></div></div>
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews To enable <span><strong class="command">named</strong></span> to respond appropriately
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews to DNS requests from DNSSEC aware clients,
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews <span><strong class="command">dnssec-enable</strong></span> must be set to yes.
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews (This is the default setting.)
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews To enable <span><strong class="command">named</strong></span> to validate answers from
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews other servers, the <span><strong class="command">dnssec-enable</strong></span> option
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews must be set to <strong class="userinput"><code>yes</code></strong>, and the
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews <span><strong class="command">dnssec-validation</strong></span> options must be set to
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews <strong class="userinput"><code>yes</code></strong> or <strong class="userinput"><code>auto</code></strong>.
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews If <span><strong class="command">dnssec-validation</strong></span> is set to
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews <strong class="userinput"><code>auto</code></strong>, then a default
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews trust anchor for the DNS root zone will be used.
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews If it is set to <strong class="userinput"><code>yes</code></strong>, however,
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews then at least one trust anchor must be configured
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews with a <span><strong class="command">trusted-keys</strong></span> or
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">managed-keys</strong></span> statement in
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <code class="filename">named.conf</code>, or DNSSEC validation
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein will not occur. The default setting is
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <strong class="userinput"><code>yes</code></strong>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">trusted-keys</strong></span> are copies of DNSKEY RRs
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein for zones that are used to form the first link in the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein cryptographic chain of trust. All keys listed in
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">trusted-keys</strong></span> (and corresponding zones)
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein are deemed to exist and only the listed keys will be used
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to validated the DNSKEY RRset that they are from.
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews <span><strong class="command">managed-keys</strong></span> are trusted keys which are
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews automatically kept up to date via RFC 5011 trust anchor
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews maintenance.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">trusted-keys</strong></span> and
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">managed-keys</strong></span> are described in more detail
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein later in this document.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Unlike <acronym class="acronym">BIND</acronym> 8, <acronym class="acronym">BIND</acronym>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 9 does not verify signatures on load, so zone keys for
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews authoritative zones do not need to be specified in the
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews configuration file.
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews After DNSSEC gets established, a typical DNSSEC configuration
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews will look something like the following. It has one or
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews more public keys for the root. This allows answers from
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews outside the organization to be validated. It will also
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein have several keys for parts of the namespace the organization
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews controls. These are here to ensure that <span><strong class="command">named</strong></span>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein is immune to compromises in the DNSSEC components of the security
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein of parent zones.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austeinmanaged-keys {
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein /* Root Key */
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein "." initial-key 257 3 3 "BNY4wrWM1nCfJ+CXd0rVXyYmobt7sEEfK3clRbGaTwS
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 66gKodQj+MiA21AfUVe7u99WzTLzY3qlxDhxYQQ20FQ
3eb9ec750c9088869170dda63e8899b2ba462823Mark Andrews dgxbcDTClU0CRBdiieyLMNzXG3";
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrewstrusted-keys {
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews /* Key for our organization's forward zone */
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein example.com. 257 3 5 "AwEAAaxPMcR2x0HbQV4WeZB6oEDX+r0QM6
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews 5KbhTjrW1ZaARmPhEZZe3Y9ifgEuq7vZ/z
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein GZUdEGNWy+JZzus0lUptwgjGwhUS1558Hb
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 4JKUbbOTcM8pwXlj0EiX3oDFVmjHO444gL
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein g4ywzO9WglMk7jbfW33gUKvirTHr25GL7S
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews TQUzBb5Usxt8lgnyTUHs1t3JwCY5hKZ6Cq
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein F4qJCyduieHukuY3H4XMAcR+xia2nIUPvm
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein /* Key for our reverse zone. */
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 2.0.192.IN-ADDRPA.NET. 257 3 5 "AQOnS4xn/IgOUpBPJ3bogzwc
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein xOdNax071L18QqZnQQQAVVr+i
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein LhGTnNGp3HoWQLUIzKrJVZ3zg
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein gy3WwNT6kZo6c0tszYqbtvchm
3eb9ec750c9088869170dda63e8899b2ba462823Mark Andrews siaOdS0yOI6BgPsw+YZdzlYMa
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein IJGf4M4dyoKIhzdZyQ2bYQrjy
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Q4LB0lC7aOnsMyYKHHYeRvPxj
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein IQXmdqgOJGq+vsevG06zW+1xg
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 59VvjSPsZJHeDCUyWYrvPZesZ
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein DIRvhDD52SKvbheeTJUm6Ehkz
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein dnssec-enable yes;
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein dnssec-validation yes;
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein None of the keys listed in this example are valid. In particular,
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein the root key is not valid.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein When DNSSEC validation is enabled and properly configured,
<a name="dnssec.dynamic.zones"></a>DNSSEC, Dynamic Zones, and Automatic Signing</h2></div></div></div>
zone example.net {
> update add example.net DNSKEY 256 3 7 AwEAAZn17pUF0KpbPA2c7Gz76Vb18v0teKT3EyAGfBfL8eQ8al35zz3Y I1m/SAQBxIqMfLtIwqWPdgthsu36azGQAX8=
> update add example.net DNSKEY 257 3 7 AwEAAd/7odU/64o2LGsifbLtQmtO8dFDtTAZXSX2+X3e/UNlq9IHq3Y0 XtC0Iuawl/qkaKVxXe2lo8Ct+dM6UehyCqk=
> update add example.net DNSKEY 256 3 7 AwEAAZn17pUF0KpbPA2c7Gz76Vb18v0teKT3EyAGfBfL8eQ8al35zz3Y I1m/SAQBxIqMfLtIwqWPdgthsu36azGQAX8=
> update add example.net DNSKEY 257 3 7 AwEAAd/7odU/64o2LGsifbLtQmtO8dFDtTAZXSX2+X3e/UNlq9IHq3Y0 XtC0Iuawl/qkaKVxXe2lo8Ct+dM6UehyCqk=
> update add example.net NSEC3PARAM 1 1 100 1234567890
(See <a href="man.dnssec-keygen.html" title="dnssec-keygen"><span class="refentrytitle"><span class="application">dnssec-keygen</span></span>(8)</a> and
<a href="man.dnssec-settime.html" title="dnssec-settime"><span class="refentrytitle"><span class="application">dnssec-settime</span></span>(8)</a> for more information.)
<span><strong class="command">rndc sign</strong></span> or <span><strong class="command">rndc loadkeys</strong></span>
<span><strong class="command">dnssec-keygen</strong></span> or <span><strong class="command">dnssec-settime</strong></span>),
and Usage">the section called “<span><strong class="command">managed-keys</strong></span> Statement Definition
$ <strong class="userinput"><code>dnssec-keygen -K keys -f KSK -P now -A now+2y example.net</code></strong>
$ <strong class="userinput"><code>wget <a href="" target="_top">http://www.openssl.org/source/openssl-0.9.8l.tar.gz</a></code></strong>
$ <strong class="userinput"><code>cp pkcs11.GCC4.0.2.so.4.05 /opt/pkcs11/usr/lib/libpkcs11.so</code></strong>
and "<span><strong class="command">make test</strong></span>". If "<span><strong class="command">make
$ <strong class="userinput"><code>export LD_LIBRARY_PATH=/opt/pkcs11/usr/lib:${LD_LIBRARY_PATH}</code></strong>
$ <strong class="userinput"><code>export KEYPER_LIBRARY_PATH=/opt/Keyper/PKCS11Provider</code></strong>
$ <strong class="userinput"><code>dnssec-keyfromlabel -l sample-ksk -f KSK example.net</code></strong>
by placing the PIN into the openssl.cnf file (in the above
<a name="id2572487"></a>IPv6 Support in <acronym class="acronym">BIND</acronym> 9</h2></div></div></div>
see <a href="Bv9ARM.ch09.html#ipv6addresses" title="IPv6 addresses (AAAA)">the section called “IPv6 addresses (AAAA)”</a>.
$ORIGIN example.com.