Bv9ARM.ch04.html revision ebabe300b615154d08f5577822cfd8726d2643c8
fdd80e9a55c70b36a3bf3e409b86897301c44ff8Automatic Updater - Copyright (C) 2004-2010 Internet Systems Consortium, Inc. ("ISC")
75c0816e8295e180f4bc7f10db3d0d880383bc1cMark Andrews - Copyright (C) 2000-2003 Internet Software Consortium.
4a14ce5ba00ab7bc55c99ffdcf59c7a4ab902721Automatic Updater - 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.
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<!-- $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">
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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">
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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>
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<dt><span class="sect1"><a href="Bv9ARM.ch04.html#id2570820">Split DNS</a></span></dt>
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<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>
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571339">Generate Shared Keys for Each Pair of Hosts</a></span></dt>
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571549">Copying the Shared Secret to Both Machines</a></span></dt>
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571560">Informing the Servers of the Key's Existence</a></span></dt>
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571596">Instructing the Server to Use the Key</a></span></dt>
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571654">TSIG Key Based Access Control</a></span></dt>
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571703">Errors</a></span></dt>
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<dt><span class="sect1"><a href="Bv9ARM.ch04.html#id2571717">TKEY</a></span></dt>
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<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>
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2564120">Generating Keys</a></span></dt>
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2572186">Signing the Zone</a></span></dt>
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2572267">Configuring Servers</a></span></dt>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<dt><span class="sect1"><a href="Bv9ARM.ch04.html#dnssec.dynamic.zones">DNSSEC, Dynamic Zones, and Automatic Signing</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2606953">Converting from insecure to secure</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2563505">Dynamic DNS update method</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2563541">Fully automatic zone signing</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2563691">Private-type records</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2563729">DNSKEY rollovers</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2563741">Dynamic DNS update method</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2563843">Automatic key rollovers</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2563869">NSEC3PARAM rollovers via UPDATE</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2563879">Converting from NSEC to NSEC3</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2563889">Converting from NSEC3 to NSEC</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571820">Converting from secure to insecure</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571858">Periodic re-signing</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571867">NSEC3 and OPTOUT</a></span></dt>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<dt><span class="sect1"><a href="Bv9ARM.ch04.html#rfc5011.support">Dynamic Trust Anchor Management</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571921">Validating Resolver</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2571943">Authoritative Server</a></span></dt>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<dt><span class="sect1"><a href="Bv9ARM.ch04.html#pkcs11">PKCS #11 (Cryptoki) support</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2609194">Prerequisites</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2607349">Building BIND 9 with PKCS#11</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2607444">PKCS #11 Tools</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2607543">Using the HSM</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2609585">Specifying the engine on the command line</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2634002">Running named with automatic zone re-signing</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect1"><a href="Bv9ARM.ch04.html#id2572487">IPv6 Support in <acronym class="acronym">BIND</acronym> 9</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<dt><span class="sect2"><a href="Bv9ARM.ch04.html#id2572754">Address Lookups Using AAAA Records</a></span></dt>
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<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>
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews <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
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews 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.
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews 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.
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
58d9e9169e7ab4355a0b0bfc13bc616bc5247dfeAutomatic Updater As a slave zone can also be a master to other slaves, <span><strong class="command">named</strong></span>,
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews by default, sends <span><strong class="command">NOTIFY</strong></span> messages for every zone
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews it loads. Specifying <span><strong class="command">notify master-only;</strong></span> will
58d9e9169e7ab4355a0b0bfc13bc616bc5247dfeAutomatic Updater cause <span><strong class="command">named</strong></span> to only send <span><strong class="command">NOTIFY</strong></span> for master
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews 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.
acb72d5e2c83b597332e3eb0c7d59e1142f1adfdMark Andrews Dynamic update is enabled by including an
3cddb2c552ee6582e8db0849c28747f6b6ca57feAutomatic Updater <span><strong class="command">allow-update</strong></span> or an <span><strong class="command">update-policy</strong></span>
3cddb2c552ee6582e8db0849c28747f6b6ca57feAutomatic Updater clause in the <span><strong class="command">zone</strong></span> statement.
3cddb2c552ee6582e8db0849c28747f6b6ca57feAutomatic Updater If the zone's <span><strong class="command">update-policy</strong></span> is set to
3cddb2c552ee6582e8db0849c28747f6b6ca57feAutomatic Updater <strong class="userinput"><code>local</code></strong>, updates to the zone
3cddb2c552ee6582e8db0849c28747f6b6ca57feAutomatic Updater will be permitted for the key <code class="varname">local-ddns</code>,
ca67ebfe9eef0b8f04179f7e511a19e0337a5422Automatic Updater which will be generated by <span><strong class="command">named</strong></span> at startup.
3cddb2c552ee6582e8db0849c28747f6b6ca57feAutomatic Updater See <a href="Bv9ARM.ch06.html#dynamic_update_policies" title="Dynamic Update Policies">the section called “Dynamic Update Policies”</a> for more details.
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater Dynamic updates using Kerberos signed requests can be made
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater using the TKEY/GSS protocol by setting either the
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater <span><strong class="command">tkey-gssapi-keytab</strong></span> option, or alternatively
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater by setting both the <span><strong class="command">tkey-gssapi-credential</strong></span>
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater and <span><strong class="command">tkey-domain</strong></span> options. Once enabled,
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater Kerberos signed requests will be matched against the update
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater policies for the zone, using the Kerberos principal as the
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater signer for the request.
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater Updating of secure zones (zones using DNSSEC) follows RFC
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater 3007: RRSIG, NSEC and NSEC3 records affected by updates are
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater automatically regenerated by the server using an online
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater zone key. Update authorization is based on transaction
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater 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.
3a5fe5abf08f16b8d31ab8ee9a788063110ef000Automatic Updater During the dump process, transient files will be created
3a5fe5abf08f16b8d31ab8ee9a788063110ef000Automatic Updater with the extensions <code class="filename">.jnw</code> and
3a5fe5abf08f16b8d31ab8ee9a788063110ef000Automatic Updater <code class="filename">.jbk</code>; under ordinary circumstances, these
3a5fe5abf08f16b8d31ab8ee9a788063110ef000Automatic Updater 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.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The zone files of dynamic zones cannot normally be edited by
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein hand because they are not guaranteed to contain the most recent
b05bdb520d83f7ecaad708fe305268c3420be01dMark Andrews 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>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein This will also remove the zone's <code class="filename">.jnl</code> file
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 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>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 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>.
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews 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>.
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews 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">
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<a name="id2570820"></a>Split DNS</h2></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Setting up different views, or visibility, of the DNS space to
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews internal and external resolvers is usually referred to as a
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews <span class="emphasis"><em>Split DNS</em></span> setup. There are several
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews 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.
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews However, since listing addresses of internal servers that
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews external clients cannot possibly reach can result in
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews connection delays and other annoyances, an organization may
a1b05dea35aa30b152a47115e18bbe679d3fcf19Mark Andrews choose to use a Split DNS to present a consistent view of itself
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews 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.
bea931e17b7567f09107f93ab7e25c7f00abeb9cMark Andrews<div class="titlepage"><div><div><h3 class="title">
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<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
2cc6eb92f9443695bc32fa6eed372d983d261a35Automatic Updater 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
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 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.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Queries for internal hostnames will be answered by the internal
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein servers, and queries for external hostnames will be forwarded back
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein out to the DNS servers on the bastion hosts.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein In order for all this to work properly, internal clients will
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein need to be configured to query <span class="emphasis"><em>only</em></span> the internal
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein name servers for DNS queries. This could also be enforced via
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein filtering on the network.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein If everything has been set properly, <span class="emphasis"><em>Example, Inc.</em></span>'s
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein internal clients will now be able to:
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Look up any hostnames in the <code class="literal">site1</code>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <code class="literal">site2.example.com</code> zones.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Look up any hostnames in the <code class="literal">site1.internal</code> and
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <code class="literal">site2.internal</code> domains.
b05bdb520d83f7ecaad708fe305268c3420be01dMark Andrews<li>Exchange mail with both internal and external people.</li>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Hosts on the Internet will be able to:
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Look up any hostnames in the <code class="literal">site1</code>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <code class="literal">site2.example.com</code> zones.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Exchange mail with anyone in the <code class="literal">site1</code> and
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <code class="literal">site2.example.com</code> zones.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Here is an example configuration for the setup we just
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein described above. Note that this is only configuration information;
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews 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>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein Internal DNS server config:
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austeinacl externals { <code class="varname">bastion-ips-go-here</code>; };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce forward only;
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater // forward to external servers
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews <code class="varname">bastion-ips-go-here</code>;
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater // sample allow-transfer (no one)
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater allow-transfer { none; };
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater // restrict query access
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater allow-query { internals; externals; };
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater // restrict recursion
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater allow-recursion { internals; };
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater// sample master zone
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce type master;
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater // do normal iterative resolution (do not forward)
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater forwarders { };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce allow-query { internals; externals; };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce allow-transfer { internals; };
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater// sample slave zone
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce masters { 172.16.72.3; };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce forwarders { };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce allow-query { internals; externals; };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce allow-transfer { internals; };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce type master;
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce forwarders { };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce allow-query { internals; };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce allow-transfer { internals; }
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce masters { 172.16.72.3; };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce forwarders { };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce allow-query { internals };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce allow-transfer { internals; }
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein External (bastion host) DNS server config:
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austeinacl internals { 172.16.72.0/24; 192.168.1.0/24; };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luceacl externals { bastion-ips-go-here; };
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater // sample allow-transfer (no one)
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater allow-transfer { none; };
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater // default query access
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater allow-query { any; };
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater // restrict cache access
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater allow-query-cache { internals; externals; };
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater // restrict recursion
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater allow-recursion { internals; externals; };
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater// sample slave zone
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce type master;
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce allow-transfer { internals; externals; };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce masters { another_bastion_host_maybe; };
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce allow-transfer { internals; externals; }
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein In the <code class="filename">resolv.conf</code> (or equivalent) on
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein the bastion host(s):
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Lucenameserver 172.16.72.2
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Lucenameserver 172.16.72.3
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Lucenameserver 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
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews (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
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews keys and using transaction signatures with <acronym class="acronym">BIND</acronym>.
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews <acronym class="acronym">BIND</acronym> primarily supports TSIG for server
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein to server communication.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein This includes zone transfer, notify, and recursive query messages.
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews Resolvers based on newer versions of <acronym class="acronym">BIND</acronym> 8 have limited support
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews TSIG can also be useful for dynamic update. A primary
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews server for a dynamic zone should control access to the dynamic
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews update service, but IP-based access control is insufficient.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 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
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews <code class="option">-y</code> command line options or inline by use
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews of the <span><strong class="command">key</strong></span>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h3 class="title">
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<a name="id2571339"></a>Generate Shared Keys for Each Pair of Hosts</h3></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 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">
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<a name="id2571356"></a>Automatic Generation</h4></div></div></div>
8ec3c085233cedb22b05da36e2773c8f357a7e45Automatic Updater 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
8ec3c085233cedb22b05da36e2773c8f357a7e45Automatic Updater are easier to read. Note that the maximum key length is the digest
8ec3c085233cedb22b05da36e2773c8f357a7e45Automatic Updater length, here 256 bits.
8ec3c085233cedb22b05da36e2773c8f357a7e45Automatic Updater <strong class="userinput"><code>dnssec-keygen -a hmac-sha256 -b 128 -n HOST host1-host2.</code></strong>
8ec3c085233cedb22b05da36e2773c8f357a7e45Automatic Updater 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.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h4 class="title">
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<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">
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<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">
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<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. {
8ec3c085233cedb22b05da36e2773c8f357a7e45Automatic Updater algorithm hmac-sha256;
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The secret is the one generated above. Since this is a secret, it
8ec3c085233cedb22b05da36e2773c8f357a7e45Automatic Updater is recommended that either <code class="filename">named.conf</code> be
8ec3c085233cedb22b05da36e2773c8f357a7e45Automatic Updater non-world readable, or the key directive be added to a non-world
8ec3c085233cedb22b05da36e2773c8f357a7e45Automatic Updater 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.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h3 class="title">
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<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
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 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 {
f293a69bcd1c1dd7bdac8f4102fc2398b9e475c8Eric Luce 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
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 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
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 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">
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<a name="id2571654"></a>TSIG Key Based Access Control</h3></div></div></div>
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews <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>
9c6a5d1f22f972232d7a9fd5c5fa64f10bacbdffAutomatic Updater 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
acb72d5e2c83b597332e3eb0c7d59e1142f1adfdMark Andrews was signed by a key named "<span><strong class="command">host1-host2.</strong></span>".
3cddb2c552ee6582e8db0849c28747f6b6ca57feAutomatic Updater See <a href="Bv9ARM.ch06.html#dynamic_update_policies" title="Dynamic Update Policies">the section called “Dynamic Update Policies”</a> for a discussion of
3cddb2c552ee6582e8db0849c28747f6b6ca57feAutomatic Updater the more flexible <span><strong class="command">update-policy</strong></span> statement.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h3 class="title">
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<a name="id2571703"></a>Errors</h3></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The processing of TSIG signed messages can result in
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein several errors. If a signed message is sent to a non-TSIG aware
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews 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
bea931e17b7567f09107f93ab7e25c7f00abeb9cMark Andrews verified. In any of these cases, the message's rcode (response code) is set to
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews NOTAUTH (not authenticated).
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h2 class="title" style="clear: both">
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<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
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews or assigned. <acronym class="acronym">BIND</acronym> 9 implements only one of
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 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
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 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.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein 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">
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<a name="id2563984"></a>SIG(0)</h2></div></div></div>
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews <acronym class="acronym">BIND</acronym> 9 partially supports DNSSEC SIG(0)
a1ad6695ed6f988406cf155aa26376f84f73bcb9Automatic Updater 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
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews 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,
bea931e17b7567f09107f93ab7e25c7f00abeb9cMark Andrews defined in RFC 4033, RFC 4034, and RFC 4035.
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews 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
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews 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
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews 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
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews 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">
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<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.
b05bdb520d83f7ecaad708fe305268c3420be01dMark Andrews 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
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <code class="filename">Kchild.example.+005+12345.private</code>
bea931e17b7567f09107f93ab7e25c7f00abeb9cMark Andrews 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>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein used to generate signatures, and the public key (in the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <code class="filename">.key</code> file) is used for signature
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein verification.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein To generate another key with the same properties (but with
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein a different key tag), repeat the above command.
28b3569d6248168e6c00caab951521cc8141a49dAutomatic Updater The <span><strong class="command">dnssec-keyfromlabel</strong></span> program is used
28b3569d6248168e6c00caab951521cc8141a49dAutomatic Updater to get a key pair from a crypto hardware and build the key
28b3569d6248168e6c00caab951521cc8141a49dAutomatic Updater files. Its usage is similar to <span><strong class="command">dnssec-keygen</strong></span>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The public keys should be inserted into the zone file by
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein including the <code class="filename">.key</code> files using
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span><strong class="command">$INCLUDE</strong></span> statements.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h3 class="title">
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<a name="id2572186"></a>Signing the Zone</h3></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The <span><strong class="command">dnssec-signzone</strong></span> program is used
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater to sign a zone.
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater Any <code class="filename">keyset</code> files corresponding to
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater secure subzones should be present. The zone signer will
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater generate <code class="literal">NSEC</code>, <code class="literal">NSEC3</code>
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater and <code class="literal">RRSIG</code> records for the zone, as
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater well as <code class="literal">DS</code> for the child zones if
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater <code class="literal">'-g'</code> is specified. If <code class="literal">'-g'</code>
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater is not specified, then DS RRsets for the secure child
38417cbfb1a328c20b5b723b8584a02c57f88897Automatic Updater zones need to be added manually.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein The following command signs the zone, assuming it is in a
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein file called <code class="filename">zone.child.example</code>. By
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein default, all zone keys which have an available private key are
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein used to generate signatures.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <strong class="userinput"><code>dnssec-signzone -o child.example zone.child.example</code></strong>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein One output file is produced:
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <code class="filename">zone.child.example.signed</code>. This
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein should be referenced by <code class="filename">named.conf</code>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein input file for the zone.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<p><span><strong class="command">dnssec-signzone</strong></span>
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews will also produce a keyset and dsset files and optionally a
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein dlvset file. These are used to provide the parent zone
a1b05dea35aa30b152a47115e18bbe679d3fcf19Mark Andrews administrators with the <code class="literal">DNSKEYs</code> (or their
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein corresponding <code class="literal">DS</code> records) that are the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein secure entry point to the zone.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h3 class="title">
66f25f2ceeb589e67efe7af2413baaa3426b0042Automatic Updater<a name="id2572267"></a>Configuring Servers</h3></div></div></div>
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews To enable <span><strong class="command">named</strong></span> to respond appropriately
b05bdb520d83f7ecaad708fe305268c3420be01dMark Andrews to DNS requests from DNSSEC aware clients,
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews <span><strong class="command">dnssec-enable</strong></span> must be set to yes.
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater (This is the default setting.)
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews To enable <span><strong class="command">named</strong></span> to validate answers from
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater other servers, the <span><strong class="command">dnssec-enable</strong></span> option
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater must be set to <strong class="userinput"><code>yes</code></strong>, and the
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater <span><strong class="command">dnssec-validation</strong></span> options must be set to
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater <strong class="userinput"><code>yes</code></strong> or <strong class="userinput"><code>auto</code></strong>.
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater If <span><strong class="command">dnssec-validation</strong></span> is set to
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater <strong class="userinput"><code>auto</code></strong>, then a default
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater trust anchor for the DNS root zone will be used.
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater If it is set to <strong class="userinput"><code>yes</code></strong>, however,
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater then at least one trust anchor must be configured
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater with a <span><strong class="command">trusted-keys</strong></span> or
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater <span><strong class="command">managed-keys</strong></span> statement in
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater <code class="filename">named.conf</code>, or DNSSEC validation
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater will not occur. The default setting is
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater <strong class="userinput"><code>yes</code></strong>.
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews <span><strong class="command">trusted-keys</strong></span> are copies of DNSKEY RRs
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews for zones that are used to form the first link in the
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews cryptographic chain of trust. All keys listed in
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews <span><strong class="command">trusted-keys</strong></span> (and corresponding zones)
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews are deemed to exist and only the listed keys will be used
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews to validated the DNSKEY RRset that they are from.
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater <span><strong class="command">managed-keys</strong></span> are trusted keys which are
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater automatically kept up to date via RFC 5011 trust anchor
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater <span><strong class="command">trusted-keys</strong></span> and
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater <span><strong class="command">managed-keys</strong></span> are described in more detail
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews later in this document.
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews Unlike <acronym class="acronym">BIND</acronym> 8, <acronym class="acronym">BIND</acronym>
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews 9 does not verify signatures on load, so zone keys for
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews authoritative zones do not need to be specified in the
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews configuration file.
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews After DNSSEC gets established, a typical DNSSEC configuration
d3907d27cc138f45772d3d63082ae02c7659148aAutomatic Updater will look something like the following. It has one or
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews more public keys for the root. This allows answers from
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews outside the organization to be validated. It will also
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews have several keys for parts of the namespace the organization
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater controls. These are here to ensure that <span><strong class="command">named</strong></span>
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater is immune to compromises in the DNSSEC components of the security
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews of parent zones.
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews /* Root Key */
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater "." initial-key 257 3 3 "BNY4wrWM1nCfJ+CXd0rVXyYmobt7sEEfK3clRbGaTwS
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater JxrGkxJWoZu6I7PzJu/E9gx4UC1zGAHlXKdE4zYIpRh
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater aBKnvcC2U9mZhkdUpd1Vso/HAdjNe8LmMlnzY3zy2Xy
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater 4klWOADTPzSv9eamj8V18PHGjBLaVtYvk/ln5ZApjYg
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater hf+6fElrmLkdaz MQ2OCnACR817DF4BBa7UR/beDHyp
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater 5iWTXWSi6XmoJLbG9Scqc7l70KDqlvXR3M/lUUVRbke
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater g1IPJSidmK3ZyCllh4XSKbje/45SKucHgnwU5jefMtq
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater 66gKodQj+MiA21AfUVe7u99WzTLzY3qlxDhxYQQ20FQ
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater 97S+LKUTpQcq27R7AT3/V5hRQxScINqwcz4jYqZD2fQ
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater dgxbcDTClU0CRBdiieyLMNzXG3";
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater /* Key for our organization's forward zone */
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater example.com. 257 3 5 "AwEAAaxPMcR2x0HbQV4WeZB6oEDX+r0QM6
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater 5KbhTjrW1ZaARmPhEZZe3Y9ifgEuq7vZ/z
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater GZUdEGNWy+JZzus0lUptwgjGwhUS1558Hb
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater 4JKUbbOTcM8pwXlj0EiX3oDFVmjHO444gL
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater g4ywzO9WglMk7jbfW33gUKvirTHr25GL7S
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater TQUzBb5Usxt8lgnyTUHs1t3JwCY5hKZ6Cq
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater F4qJCyduieHukuY3H4XMAcR+xia2nIUPvm
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater /* Key for our reverse zone. */
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater 2.0.192.IN-ADDRPA.NET. 257 3 5 "AQOnS4xn/IgOUpBPJ3bogzwc
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater xOdNax071L18QqZnQQQAVVr+i
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater LhGTnNGp3HoWQLUIzKrJVZ3zg
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater gy3WwNT6kZo6c0tszYqbtvchm
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater siaOdS0yOI6BgPsw+YZdzlYMa
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater IJGf4M4dyoKIhzdZyQ2bYQrjy
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater Q4LB0lC7aOnsMyYKHHYeRvPxj
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater IQXmdqgOJGq+vsevG06zW+1xg
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater 59VvjSPsZJHeDCUyWYrvPZesZ
2895f101b5585a19015ac2c2c1e1812ac467fa12Automatic Updater DIRvhDD52SKvbheeTJUm6Ehkz
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews dnssec-enable yes;
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews dnssec-validation yes;
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
47012ae6dbf18a2503d7b33c1c9583dc38625cb7Mark Andrews None of the keys listed in this example are valid. In particular,
6101b9f0d904a708e900a74abc16d1e0eda67264Mark Andrews the root key is not valid.
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater When DNSSEC validation is enabled and properly configured,
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater the resolver will reject any answers from signed, secure zones
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater which fail to validate, and will return SERVFAIL to the client.
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater Responses may fail to validate for any of several reasons,
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater including missing, expired, or invalid signatures, a key which
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater does not match the DS RRset in the parent zone, or an insecure
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater response from a zone which, according to its parent, should have
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater When the validator receives a response from an unsigned zone
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater that has a signed parent, it must confirm with the parent
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater that the zone was intentionally left unsigned. It does
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater this by verifying, via signed and validated NSEC/NSEC3 records,
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater that the parent zone contains no DS records for the child.
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater If the validator <span class="emphasis"><em>can</em></span> prove that the zone
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater is insecure, then the response is accepted. However, if it
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater cannot, then it must assume an insecure response to be a
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater forgery; it rejects the response and logs an error.
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater The logged error reads "insecurity proof failed" and
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater "got insecure response; parent indicates it should be secure".
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater (Prior to BIND 9.7, the logged error was "not insecure".
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater This referred to the zone, not the response.)
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h2 class="title" style="clear: both">
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<a name="dnssec.dynamic.zones"></a>DNSSEC, Dynamic Zones, and Automatic Signing</h2></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>As of BIND 9.7.0 it is possible to change a dynamic zone
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater from insecure to signed and back again. A secure zone can use
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater either NSEC or NSEC3 chains.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2606953"></a>Converting from insecure to secure</h3></div></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>Changing a zone from insecure to secure can be done in two
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater ways: using a dynamic DNS update, or the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">auto-dnssec</strong></span> zone option.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>For either method, you need to configure
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">named</strong></span> so that it can see the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <code class="filename">K*</code> files which contain the public and private
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater parts of the keys that will be used to sign the zone. These files
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater will have been generated by
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">dnssec-keygen</strong></span>. You can do this by placing them
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater in the key-directory, as specified in
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <code class="filename">named.conf</code>:</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater update-policy local;
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>If one KSK and one ZSK DNSKEY key have been generated, this
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater configuration will cause all records in the zone to be signed
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater with the ZSK, and the DNSKEY RRset to be signed with the KSK as
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater well. An NSEC chain will be generated as part of the initial
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater signing process.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2563505"></a>Dynamic DNS update method</h3></div></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>To insert the keys via dynamic update:</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater > update add example.net DNSKEY 256 3 7 AwEAAZn17pUF0KpbPA2c7Gz76Vb18v0teKT3EyAGfBfL8eQ8al35zz3Y I1m/SAQBxIqMfLtIwqWPdgthsu36azGQAX8=
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater > update add example.net DNSKEY 257 3 7 AwEAAd/7odU/64o2LGsifbLtQmtO8dFDtTAZXSX2+X3e/UNlq9IHq3Y0 XtC0Iuawl/qkaKVxXe2lo8Ct+dM6UehyCqk=
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>While the update request will complete almost immediately,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater the zone will not be completely signed until
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">named</strong></span> has had time to walk the zone and
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater generate the NSEC and RRSIG records. The NSEC record at the apex
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater will be added last, to signal that there is a complete NSEC
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>If you wish to sign using NSEC3 instead of NSEC, you should
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater add an NSEC3PARAM record to the initial update request. If you
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater wish the NSEC3 chain to have the OPTOUT bit set, set it in the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater flags field of the NSEC3PARAM record.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater > update add example.net DNSKEY 256 3 7 AwEAAZn17pUF0KpbPA2c7Gz76Vb18v0teKT3EyAGfBfL8eQ8al35zz3Y I1m/SAQBxIqMfLtIwqWPdgthsu36azGQAX8=
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater > update add example.net DNSKEY 257 3 7 AwEAAd/7odU/64o2LGsifbLtQmtO8dFDtTAZXSX2+X3e/UNlq9IHq3Y0 XtC0Iuawl/qkaKVxXe2lo8Ct+dM6UehyCqk=
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater > update add example.net NSEC3PARAM 1 1 100 1234567890
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>Again, this update request will complete almost
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater immediately; however, the record won't show up until
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">named</strong></span> has had a chance to build/remove the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater relevant chain. A private type record will be created to record
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater the state of the operation (see below for more details), and will
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater be removed once the operation completes.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>While the initial signing and NSEC/NSEC3 chain generation
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater is happening, other updates are possible as well.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2563541"></a>Fully automatic zone signing</h3></div></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>To enable automatic signing, add the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">auto-dnssec</strong></span> option to the zone statement in
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">auto-dnssec</strong></span> has two possible arguments:
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <code class="constant">maintain</code>.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">auto-dnssec allow</strong></span>,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">named</strong></span> can search the key directory for keys
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater matching the zone, insert them into the zone, and use them to
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater sign the zone. It will do so only when it receives an
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater <span><strong class="command">rndc sign <zonename></strong></span> or
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater <span><strong class="command">rndc loadkeys <zonename></strong></span> command.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">auto-dnssec maintain</strong></span> includes the above
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater functionality, but will also automatically adjust the zone's
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater DNSKEY records on schedule according to the keys' timing metadata.
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater (See <a href="man.dnssec-keygen.html" title="dnssec-keygen"><span class="refentrytitle"><span class="application">dnssec-keygen</span></span>(8)</a> and
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <a href="man.dnssec-settime.html" title="dnssec-settime"><span class="refentrytitle"><span class="application">dnssec-settime</span></span>(8)</a> for more information.)
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater If keys are present in the key directory the first time the zone
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater is loaded, it will be signed immediately, without waiting for an
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater <span><strong class="command">rndc sign</strong></span> or <span><strong class="command">rndc loadkeys</strong></span>
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater command. (Those commands can still be used when there are unscheduled
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater key changes, however.)
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">auto-dnssec</strong></span> option requires the zone to be
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater configured to allow dynamic updates, by adding an
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">allow-update</strong></span> or
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">update-policy</strong></span> statement to the zone
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater configuration. If this has not been done, the configuration will
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2563691"></a>Private-type records</h3></div></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>The state of the signing process is signaled by
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater private-type records (with a default type value of 65534). When
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater signing is complete, these records will have a nonzero value for
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater the final octet (for those records which have a nonzero initial
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>The private type record format: If the first octet is
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater non-zero then the record indicates that the zone needs to be
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater signed with the key matching the record, or that all signatures
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater that match the record should be removed.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater��algorithm�(octet�1)<br>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater��key�id�in�network�order�(octet�2�and�3)<br>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater��removal�flag�(octet�4)<br>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater��complete�flag�(octet�5)<br>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>Only records flagged as "complete" can be removed via
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater dynamic update. Attempts to remove other private type records
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater will be silently ignored.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>If the first octet is zero (this is a reserved algorithm
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater number that should never appear in a DNSKEY record) then the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater record indicates changes to the NSEC3 chains are in progress. The
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater rest of the record contains an NSEC3PARAM record. The flag field
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater tells what operation to perform based on the flag bits.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater��0x01�OPTOUT<br>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater��0x80�CREATE<br>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater��0x40�REMOVE<br>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater��0x20�NONSEC<br>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2563729"></a>DNSKEY rollovers</h3></div></div></div></div>
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater<p>As with insecure-to-secure conversions, rolling DNSSEC
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater keys can be done in two ways: using a dynamic DNS update, or the
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater <span><strong class="command">auto-dnssec</strong></span> zone option.</p>
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater<div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2563741"></a>Dynamic DNS update method</h3></div></div></div></div>
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater<p> To perform key rollovers via dynamic update, you need to add
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater the <code class="filename">K*</code> files for the new keys so that
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">named</strong></span> can find them. You can then add the new
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater DNSKEY RRs via dynamic update.
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">named</strong></span> will then cause the zone to be signed
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater with the new keys. When the signing is complete the private type
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater records will be updated so that the last octet is non
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>If this is for a KSK you need to inform the parent and any
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater trust anchor repositories of the new KSK.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>You should then wait for the maximum TTL in the zone before
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater removing the old DNSKEY. If it is a KSK that is being updated,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater you also need to wait for the DS RRset in the parent to be
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater updated and its TTL to expire. This ensures that all clients will
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater be able to verify at least one signature when you remove the old
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>The old DNSKEY can be removed via UPDATE. Take care to
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater specify the correct key.
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">named</strong></span> will clean out any signatures generated
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater by the old key after the update completes.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2563843"></a>Automatic key rollovers</h3></div></div></div></div>
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater<p>When a new key reaches its activation date (as set by
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater <span><strong class="command">dnssec-keygen</strong></span> or <span><strong class="command">dnssec-settime</strong></span>),
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater if the <span><strong class="command">auto-dnssec</strong></span> zone option is set to
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater <code class="constant">maintain</code>, <span><strong class="command">named</strong></span> will
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater automatically carry out the key rollover. If the key's algorithm
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater has not previously been used to sign the zone, then the zone will
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater be fully signed as quickly as possible. However, if the new key
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater is replacing an existing key of the same algorithm, then the
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater zone will be re-signed incrementally, with signatures from the
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater old key being replaced with signatures from the new key as their
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater signature validity periods expire. By default, this rollover
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater completes in 30 days, after which it will be safe to remove the
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater old key from the DNSKEY RRset.</p>
3acf5eb97cebc2ba868e6ac4a4e01e6d1be0c892Automatic Updater<div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2563869"></a>NSEC3PARAM rollovers via UPDATE</h3></div></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>Add the new NSEC3PARAM record via dynamic update. When the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater new NSEC3 chain has been generated, the NSEC3PARAM flag field
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater will be zero. At this point you can remove the old NSEC3PARAM
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater record. The old chain will be removed after the update request
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater completes.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2563879"></a>Converting from NSEC to NSEC3</h3></div></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>To do this, you just need to add an NSEC3PARAM record. When
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater the conversion is complete, the NSEC chain will have been removed
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater and the NSEC3PARAM record will have a zero flag field. The NSEC3
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater chain will be generated before the NSEC chain is
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater destroyed.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2563889"></a>Converting from NSEC3 to NSEC</h3></div></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>To do this, use <span><strong class="command">nsupdate</strong></span> to
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater remove all NSEC3PARAM records with a zero flag
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater field. The NSEC chain will be generated before the NSEC3 chain is
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2571820"></a>Converting from secure to insecure</h3></div></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>To convert a signed zone to unsigned using dynamic DNS,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater delete all the DNSKEY records from the zone apex using
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">nsupdate</strong></span>. All signatures, NSEC or NSEC3 chains,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater and associated NSEC3PARAM records will be removed automatically.
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater This will take place after the update request completes.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p> This requires the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">dnssec-secure-to-insecure</strong></span> option to be set to
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <strong class="userinput"><code>yes</code></strong> in
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <code class="filename">named.conf</code>.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>In addition, if the <span><strong class="command">auto-dnssec maintain</strong></span>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater zone statement is used, it should be removed or changed to
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">allow</strong></span> instead (or it will re-sign).
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2571858"></a>Periodic re-signing</h3></div></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>In any secure zone which supports dynamic updates, named
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater will periodically re-sign RRsets which have not been re-signed as
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater a result of some update action. The signature lifetimes will be
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater adjusted so as to spread the re-sign load over time rather than
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater all at once.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2571867"></a>NSEC3 and OPTOUT</h3></div></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">named</strong></span> only supports creating new NSEC3 chains
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater where all the NSEC3 records in the zone have the same OPTOUT
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">named</strong></span> supports UPDATES to zones where the NSEC3
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater records in the chain have mixed OPTOUT state.
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">named</strong></span> does not support changing the OPTOUT
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater state of an individual NSEC3 record, the entire chain needs to be
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater changed if the OPTOUT state of an individual NSEC3 needs to be
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="titlepage"><div><div><h2 class="title" style="clear: both">
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<a name="rfc5011.support"></a>Dynamic Trust Anchor Management</h2></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>BIND 9.7.0 introduces support for RFC 5011, dynamic trust
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater anchor management. Using this feature allows
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">named</strong></span> to keep track of changes to critical
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater DNSSEC keys without any need for the operator to make changes to
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater configuration files.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2571921"></a>Validating Resolver</h3></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>To configure a validating resolver to use RFC 5011 to
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater maintain a trust anchor, configure the trust anchor using a
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">managed-keys</strong></span> statement. Information about
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater this can be found in
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <a href="Bv9ARM.ch06.html#managed-keys" title="managed-keys Statement Definition
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater and Usage">the section called “<span><strong class="command">managed-keys</strong></span> Statement Definition
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2571943"></a>Authoritative Server</h3></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>To set up an authoritative zone for RFC 5011 trust anchor
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater maintenance, generate two (or more) key signing keys (KSKs) for
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater the zone. Sign the zone with one of them; this is the "active"
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater KSK. All KSK's which do not sign the zone are "stand-by"
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>Any validating resolver which is configured to use the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater active KSK as an RFC 5011-managed trust anchor will take note
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater of the stand-by KSKs in the zone's DNSKEY RRset, and store them
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater for future reference. The resolver will recheck the zone
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater periodically, and after 30 days, if the new key is still there,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater then the key will be accepted by the resolver as a valid trust
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater anchor for the zone. Any time after this 30-day acceptance
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater timer has completed, the active KSK can be revoked, and the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater zone can be "rolled over" to the newly accepted key.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>The easiest way to place a stand-by key in a zone is to
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater use the "smart signing" features of
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">dnssec-keygen</strong></span> and
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">dnssec-signzone</strong></span>. If a key with a publication
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater date in the past, but an activation date which is unset or in
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">dnssec-signzone -S</strong></span>" will include the DNSKEY
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater record in the zone, but will not sign with it:</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>dnssec-keygen -K keys -f KSK -P now -A now+2y example.net</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>dnssec-signzone -S -K keys example.net</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>To revoke a key, the new command
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">dnssec-revoke</strong></span> has been added. This adds the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater REVOKED bit to the key flags and re-generates the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <code class="filename">K*.private</code> files.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>After revoking the active key, the zone must be signed
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater with both the revoked KSK and the new active KSK. (Smart
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater signing takes care of this automatically.)</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>Once a key has been revoked and used to sign the DNSKEY
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater RRset in which it appears, that key will never again be
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater accepted as a valid trust anchor by the resolver. However,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater validation can proceed using the new active key (which had been
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater accepted by the resolver when it was a stand-by key).</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>See RFC 5011 for more details on key rollover
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater scenarios.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>When a key has been revoked, its key ID changes,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater increasing by 128, and wrapping around at 65535. So, for
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater example, the key "<code class="filename">Kexample.com.+005+10000</code>" becomes
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater "<code class="filename">Kexample.com.+005+10128</code>".</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>If two keys have ID's exactly 128 apart, and one is
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater revoked, then the two key ID's will collide, causing several
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater problems. To prevent this,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">dnssec-keygen</strong></span> will not generate a new key if
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater another key is present which may collide. This checking will
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater only occur if the new keys are written to the same directory
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater which holds all other keys in use for that zone.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>Older versions of BIND 9 did not have this precaution.
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater Exercise caution if using key revocation on keys that were
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater generated by previous releases, or if using keys stored in
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater multiple directories or on multiple machines.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>It is expected that a future release of BIND 9 will
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater address this problem in a different way, by storing revoked
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater keys with their original unrevoked key ID's.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="titlepage"><div><div><h2 class="title" style="clear: both">
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<a name="pkcs11"></a>PKCS #11 (Cryptoki) support</h2></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>PKCS #11 (Public Key Cryptography Standard #11) defines a
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater platform- independent API for the control of hardware security
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater modules (HSMs) and other cryptographic support devices.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>BIND 9 is known to work with two HSMs: The Sun SCA 6000
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater cryptographic acceleration board, tested under Solaris x86, and
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater the AEP Keyper network-attached key storage device, tested with
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater Debian Linux, Solaris x86 and Windows Server 2003.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2609194"></a>Prerequisites</h3></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>See the HSM vendor documentation for information about
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater installing, initializing, testing and troubleshooting the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>BIND 9 uses OpenSSL for cryptography, but stock OpenSSL
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater does not yet fully support PKCS #11. However, a PKCS #11 engine
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater for OpenSSL is available from the OpenSolaris project. It has
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater been modified by ISC to work with with BIND 9, and to provide
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater new features such as PIN management and key by
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater reference.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>The patched OpenSSL depends on a "PKCS #11 provider".
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater This is a shared library object, providing a low-level PKCS #11
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater interface to the HSM hardware. It is dynamically loaded by
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater OpenSSL at runtime. The PKCS #11 provider comes from the HSM
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater vendor, and and is specific to the HSM to be controlled.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>There are two "flavors" of PKCS #11 support provided by
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater the patched OpenSSL, one of which must be chosen at
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater configuration time. The correct choice depends on the HSM
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<li><p>Use 'crypto-accelerator' with HSMs that have hardware
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater cryptographic acceleration features, such as the SCA 6000
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater board. This causes OpenSSL to run all supported
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater cryptographic operations in the HSM.</p></li>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<li><p>Use 'sign-only' with HSMs that are designed to
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater function primarily as secure key storage devices, but lack
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater hardware acceleration. These devices are highly secure, but
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater are not necessarily any faster at cryptography than the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater system CPU — often, they are slower. It is therefore
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater most efficient to use them only for those cryptographic
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater functions that require access to the secured private key,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater such as zone signing, and to use the system CPU for all
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater other computationally-intensive operations. The AEP Keyper
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>The modified OpenSSL code is included in the BIND 9.7.0
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater release, in the form of a context diff against the latest OpenSSL.
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater The latest OpenSSL version at the time of the BIND release
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater ISC will provide an updated patch as new versions of OpenSSL
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater are released. The version number in the following examples
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater is expected to change.</div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater Before building BIND 9 with PKCS #11 support, it will be
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater necessary to build OpenSSL with this patch in place and inform
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater it of the path to the HSM-specific PKCS #11 provider
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>wget <a href="" target="_top">http://www.openssl.org/source/openssl-0.9.8l.tar.gz</a></code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>tar zxf openssl-0.9.8l.tar.gz</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>Apply the patch from the BIND 9 release:</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>patch -p1 -d openssl-0.9.8l \
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater < bind-9.7.0/bin/pkcs11/openssl-0.9.8l-patch</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<h3 class="title">Note</h3>(Note that the patch file may not be compatible with the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater "patch" utility on all operating systems. You may need to
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater install GNU patch.)</div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>When building OpenSSL, place it in a non-standard
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater location so that it does not interfere with OpenSSL libraries
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater elsewhere on the system. In the following examples, we choose
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater to install into "/opt/pkcs11/usr". We will use this location
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater when we configure BIND 9.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="titlepage"><div><div><h4 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2607106"></a>Building OpenSSL for the AEP Keyper on Linux</h4></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>The AEP Keyper is a highly secure key storage device,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater but does not provide hardware cryptographic acceleration. It
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater can carry out cryptographic operations, but it is probably
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater slower than your system's CPU. Therefore, we choose the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater 'sign-only' flavor when building OpenSSL.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>The Keyper-specific PKCS #11 provider library is
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater delivered with the Keyper software. In this example, we place
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>cp pkcs11.GCC4.0.2.so.4.05 /opt/pkcs11/usr/lib/libpkcs11.so</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>This library is only available for Linux as a 32-bit
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater binary. If we are compiling on a 64-bit Linux system, it is
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater necessary to force a 32-bit build, by specifying -m32 in the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater build options.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>Finally, the Keyper library requires threads, so we
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater must specify -pthread.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>cd openssl-0.9.8l</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>/Configure linux-generic32 -m32 -pthread \
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater --pk11-libname=/opt/pkcs11/usr/lib/libpkcs11.so \
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater --pk11-flavor=sign-only \
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>After configuring, run "<span><strong class="command">make</strong></span>"
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater and "<span><strong class="command">make test</strong></span>". If "<span><strong class="command">make
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater test</strong></span>" fails with "pthread_atfork() not found", you forgot to
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater add the -pthread above.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="titlepage"><div><div><h4 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2607243"></a>Building OpenSSL for the SCA 6000 on Solaris</h4></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>The SCA-6000 PKCS #11 provider is installed as a system
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater library, libpkcs11. It is a true crypto accelerator, up to 4
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater times faster than any CPU, so the flavor shall be
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater 'crypto-accelerator'.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>In this example, we are building on Solaris x86 on an
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater AMD64 system.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>cd openssl-0.9.8l</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>/Configure solaris64-x86_64-cc \
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater --pk11-flavor=crypto-accelerator \
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>(For a 32-bit build, use "solaris-x86-cc" and
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>After configuring, run
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">make</strong></span> and
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">make test</strong></span>.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>Once you have built OpenSSL, run
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater "<span><strong class="command">apps/openssl engine pkcs11</strong></span>" to confirm
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater that PKCS #11 support was compiled in correctly. The output
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater should be one of the following lines, depending on the flavor
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater (pkcs11) PKCS #11 engine support (sign only)
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater (pkcs11) PKCS #11 engine support (crypto accelerator)
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater "<span><strong class="command">apps/openssl engine pkcs11 -t</strong></span>". This will
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater attempt to initialize the PKCS #11 engine. If it is able to
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater do so successfully, it will report
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater “<span class="quote"><code class="literal">[ available ]</code></span>”.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>If the output is correct, run
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater "<span><strong class="command">make install</strong></span>" which will install the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater modified OpenSSL suite to
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <code class="filename">/opt/pkcs11/usr</code>.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2607349"></a>Building BIND 9 with PKCS#11</h3></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>When building BIND 9, the location of the custom-built
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater OpenSSL library must be specified via configure.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="titlepage"><div><div><h4 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2607357"></a>Configuring BIND 9 for Linux</h4></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>To link with the PKCS #11 provider, threads must be
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater enabled in the BIND 9 build.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>The PKCS #11 library for the AEP Keyper is currently
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater only available as a 32-bit binary. If we are building on a
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater 64-bit host, we must force a 32-bit build by adding "-m32" to
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater the CC options on the "configure" command line.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>cd /bind-9.7.0</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>/configure CC="gcc -m32" --enable-threads \
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater --with-pkcs11=/opt/pkcs11/usr/lib/libpkcs11.so</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="titlepage"><div><div><h4 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2607388"></a>Configuring BIND 9 for Solaris</h4></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>To link with the PKCS #11 provider, threads must be
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater enabled in the BIND 9 build.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>cd /bind-9.7.0</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>/configure CC="cc -xarch=amd64" --enable-threads \
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater --with-pkcs11=/usr/lib/64/libpkcs11.so</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>(For a 32-bit build, omit CC="cc -xarch=amd64".)</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>If configure complains about OpenSSL not working, you
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater may have a 32/64-bit architecture mismatch. Or, you may have
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater incorrectly specified the path to OpenSSL (it should be the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater same as the --prefix argument to the OpenSSL
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater Configure).</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>After configuring, run
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater "<span><strong class="command">make</strong></span>",
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater "<span><strong class="command">make test</strong></span>" and
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater "<span><strong class="command">make install</strong></span>".</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2607444"></a>PKCS #11 Tools</h3></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>BIND 9 includes a minimal set of tools to operate the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater HSM, including
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">pkcs11-keygen</strong></span> to generate a new key pair
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater within the HSM,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">pkcs11-list</strong></span> to list objects currently
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater available, and
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">pkcs11-destroy</strong></span> to remove objects.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>In UNIX/Linux builds, these tools are built only if BIND
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater 9 is configured with the --with-pkcs11 option. (NOTE: If
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater --with-pkcs11 is set to "yes", rather than to the path of the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater PKCS #11 provider, then the tools will be built but the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater provider will be left undefined. Use the -m option or the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater PKCS11_PROVIDER environment variable to specify the path to the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater provider.)</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2607543"></a>Using the HSM</h3></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>First, we must set up the runtime environment so the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater OpenSSL and PKCS #11 libraries can be loaded:</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>export LD_LIBRARY_PATH=/opt/pkcs11/usr/lib:${LD_LIBRARY_PATH}</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>When operating an AEP Keyper, it is also necessary to
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater specify the location of the "machine" file, which stores
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater information about the Keyper for use by PKCS #11 provider
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater library. If the machine file is in
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <code class="filename">/opt/Keyper/PKCS11Provider/machine</code>,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>export KEYPER_LIBRARY_PATH=/opt/Keyper/PKCS11Provider</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>These environment variables must be set whenever running
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater any tool that uses the HSM, including
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">pkcs11-keygen</strong></span>,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">pkcs11-list</strong></span>,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">pkcs11-destroy</strong></span>,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">dnssec-keyfromlabel</strong></span>,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">dnssec-signzone</strong></span>,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">dnssec-keygen</strong></span>(which will use the HSM for
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater random number generation), and
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">named</strong></span>.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>We can now create and use keys in the HSM. In this case,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater we will create a 2048 bit key and give it the label
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater "sample-ksk":</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>pkcs11-keygen -b 2048 -l sample-ksk</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>pkcs11-list</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updaterobject[0]: handle 2147483658 class 3 label[8] 'sample-ksk' id[0]
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updaterobject[1]: handle 2147483657 class 2 label[8] 'sample-ksk' id[0]
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>Before using this key to sign a zone, we must create a
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater pair of BIND 9 key files. The "dnssec-keyfromlabel" utility
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater does this. In this case, we will be using the HSM key
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater "sample-ksk" as the key-signing key for "example.net":</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>dnssec-keyfromlabel -l sample-ksk -f KSK example.net</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>The resulting K*.key and K*.private files can now be used
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater to sign the zone. Unlike normal K* files, which contain both
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater public and private key data, these files will contain only the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater public key data, plus an identifier for the private key which
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater remains stored within the HSM. The HSM handles signing with the
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater private key.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>If you wish to generate a second key in the HSM for use
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater as a zone-signing key, follow the same procedure above, using a
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater different keylabel, a smaller key size, and omitting "-f KSK"
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater from the dnssec-keyfromlabel arguments:</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>pkcs11-keygen -b 1024 -l sample-zsk</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>dnssec-keyfromlabel -l sample-zsk example.net</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>Alternatively, you may prefer to generate a conventional
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater on-disk key, using dnssec-keygen:</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>dnssec-keygen example.net</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>This provides less security than an HSM key, but since
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater HSMs can be slow or cumbersome to use for security reasons, it
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater may be more efficient to reserve HSM keys for use in the less
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater frequent key-signing operation. The zone-signing key can be
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater rolled more frequently, if you wish, to compensate for a
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater reduction in key security.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>Now you can sign the zone. (Note: If not using the -S
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">dnssec-signzone</strong></span>, it will be necessary to add
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater the contents of both
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <code class="filename">K*.key</code> files to the zone master file before
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater signing it.)</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>dnssec-signzone -S example.net</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic UpdaterVerifying the zone using the following algorithms:
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic UpdaterZone signing complete:
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic UpdaterAlgorithm: NSEC3RSASHA1: ZSKs: 1, KSKs: 1 active, 0 revoked, 0 stand-by
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2609585"></a>Specifying the engine on the command line</h3></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>The OpenSSL engine can be specified in
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">named</strong></span> and all of the BIND
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">dnssec-*</strong></span> tools by using the "-E
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <engine>" command line option. If BIND 9 is built with
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater the --with-pkcs11 option, this option defaults to "pkcs11".
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater Specifying the engine will generally not be necessary unless
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater for some reason you wish to use a different OpenSSL
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>If you wish to disable use of the "pkcs11" engine —
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater for troubleshooting purposes, or because the HSM is unavailable
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater — set the engine to the empty string. For example:</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater$ <strong class="userinput"><code>dnssec-signzone -E '' -S example.net</code></strong>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">dnssec-signzone</strong></span> to run as if it were compiled
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater without the --with-pkcs11 option.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2634002"></a>Running named with automatic zone re-signing</h3></div></div></div>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <span><strong class="command">named</strong></span> to dynamically re-sign zones using HSM
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater keys, and/or to to sign new records inserted via nsupdate, then
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater named must have access to the HSM PIN. This can be accomplished
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater by placing the PIN into the openssl.cnf file (in the above
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater <code class="filename">/opt/pkcs11/usr/ssl/openssl.cnf</code>).</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>The location of the openssl.cnf file can be overridden by
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater setting the OPENSSL_CONF environment variable before running
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater openssl_conf = openssl_def
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater [ openssl_def ]
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater engines = engine_section
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater [ engine_section ]
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater pkcs11 = pkcs11_section
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater [ pkcs11_section ]
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater PIN = <em class="replaceable"><code><PLACE PIN HERE></code></em>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>This will also allow the dnssec-* tools to access the HSM
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater without PIN entry. (The pkcs11-* tools access the HSM directly,
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater not via OpenSSL, so a PIN will still be required to use
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;">
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<p>Placing the HSM's PIN in a text file in
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater this manner may reduce the security advantage of using an
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater HSM. Be sure this is what you want to do before configuring
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater OpenSSL in this way.</p>
44d0f0256fbdce130a18655023c3b06bacacbd61Automatic Updater<div class="titlepage"><div><div><h2 class="title" style="clear: both">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2572487"></a>IPv6 Support in <acronym class="acronym">BIND</acronym> 9</h2></div></div></div>
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews <acronym class="acronym">BIND</acronym> 9 fully supports all currently
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater defined forms of IPv6 name to address and address to name
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater lookups. It will also use IPv6 addresses to make queries when
cbf7f1435f332b31f51a98611ccbfcd07c42c032Automatic Updater running on an IPv6 capable system.
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews For forward lookups, <acronym class="acronym">BIND</acronym> 9 supports
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews only AAAA records. RFC 3363 deprecated the use of A6 records,
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews and client-side support for A6 records was accordingly removed
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews from <acronym class="acronym">BIND</acronym> 9.
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews However, authoritative <acronym class="acronym">BIND</acronym> 9 name servers still
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein load zone files containing A6 records correctly, answer queries
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein for A6 records, and accept zone transfer for a zone containing A6
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews For IPv6 reverse lookups, <acronym class="acronym">BIND</acronym> 9 supports
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein the traditional "nibble" format used in the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <span class="emphasis"><em>ip6.arpa</em></span> domain, as well as the older, deprecated
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews <span class="emphasis"><em>ip6.int</em></span> domain.
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews Older versions of <acronym class="acronym">BIND</acronym> 9
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews supported the "binary label" (also known as "bitstring") format,
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews but support of binary labels has been completely removed per
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews Many applications in <acronym class="acronym">BIND</acronym> 9 do not understand
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews the binary label format at all any more, and will return an
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews error if given.
71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews In particular, an authoritative <acronym class="acronym">BIND</acronym> 9
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews name server will not load a zone file containing binary labels.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein For an overview of the format and structure of IPv6 addresses,
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein see <a href="Bv9ARM.ch09.html#ipv6addresses" title="IPv6 addresses (AAAA)">the section called “IPv6 addresses (AAAA)”</a>.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2572754"></a>Address Lookups Using AAAA Records</h3></div></div></div>
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews The IPv6 AAAA record is a parallel to the IPv4 A record,
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews and, unlike the deprecated A6 record, specifies the entire
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews IPv6 address in a single record. For example,
3eb9ec750c9088869170dda63e8899b2ba462823Mark Andrewshost 3600 IN AAAA 2001:db8::1
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews Use of IPv4-in-IPv6 mapped addresses is not recommended.
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews If a host has an IPv4 address, use an A record, not
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein a AAAA, with <code class="literal">::ffff:192.168.42.1</code> as
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews the address.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<div class="titlepage"><div><div><h3 class="title">
ebabe300b615154d08f5577822cfd8726d2643c8Automatic Updater<a name="id2572843"></a>Address to Name Lookups Using Nibble Format</h3></div></div></div>
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein When looking up an address in nibble format, the address
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein components are simply reversed, just as in IPv4, and
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein <code class="literal">ip6.arpa.</code> is appended to the
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein resulting name.
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein For example, the following would provide reverse name lookup for
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein a host with address
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein$ORIGIN 0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.
ac93437301f55ed69bf85883a497a75598c628f9Automatic Updater1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0 14400 IN PTR (
60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<a accesskey="p" href="Bv9ARM.ch03.html">Prev</a>�</td>
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60e5e10f8d2e2b0c41e8abad38cacd867caa6ab2Rob Austein<td width="40%" align="left" valign="top">Chapter�3.�Name Server Configuration�</td>
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71c66a876ecca77923638d3f94cc0783152b2f03Mark Andrews<td width="40%" align="right" valign="top">�Chapter�5.�The <acronym class="acronym">BIND</acronym> 9 Lightweight Resolver</td>